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Commit | Line | Data |
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6d716ca8 | 1 | /* Fold a constant sub-tree into a single node for C-compiler |
06ceef4e | 2 | Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, |
32812a40 | 3 | 1999, 2000, 2001 Free Software Foundation, Inc. |
6d716ca8 | 4 | |
1322177d | 5 | This file is part of GCC. |
6d716ca8 | 6 | |
1322177d LB |
7 | GCC is free software; you can redistribute it and/or modify it under |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 2, or (at your option) any later | |
10 | version. | |
6d716ca8 | 11 | |
1322177d LB |
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
6d716ca8 RS |
16 | |
17 | You should have received a copy of the GNU General Public License | |
1322177d LB |
18 | along with GCC; see the file COPYING. If not, write to the Free |
19 | Software Foundation, 59 Temple Place - Suite 330, Boston, MA | |
20 | 02111-1307, USA. */ | |
6d716ca8 | 21 | |
6dc42e49 | 22 | /*@@ This file should be rewritten to use an arbitrary precision |
6d716ca8 RS |
23 | @@ representation for "struct tree_int_cst" and "struct tree_real_cst". |
24 | @@ Perhaps the routines could also be used for bc/dc, and made a lib. | |
25 | @@ The routines that translate from the ap rep should | |
26 | @@ warn if precision et. al. is lost. | |
27 | @@ This would also make life easier when this technology is used | |
28 | @@ for cross-compilers. */ | |
29 | ||
f8dac6eb | 30 | /* The entry points in this file are fold, size_int_wide, size_binop |
0da6f3db | 31 | and force_fit_type. |
6d716ca8 RS |
32 | |
33 | fold takes a tree as argument and returns a simplified tree. | |
34 | ||
35 | size_binop takes a tree code for an arithmetic operation | |
36 | and two operands that are trees, and produces a tree for the | |
37 | result, assuming the type comes from `sizetype'. | |
38 | ||
39 | size_int takes an integer value, and creates a tree constant | |
0da6f3db DE |
40 | with type from `sizetype'. |
41 | ||
42 | force_fit_type takes a constant and prior overflow indicator, and | |
43 | forces the value to fit the type. It returns an overflow indicator. */ | |
44 | ||
e9a25f70 | 45 | #include "config.h" |
2fde567e | 46 | #include "system.h" |
6d716ca8 RS |
47 | #include "flags.h" |
48 | #include "tree.h" | |
efe3eb65 | 49 | #include "rtl.h" |
0e9295cf | 50 | #include "expr.h" |
6baf1cc8 | 51 | #include "tm_p.h" |
10f0ad3d | 52 | #include "toplev.h" |
a3770a81 | 53 | #include "ggc.h" |
6d716ca8 | 54 | |
711d877c | 55 | static void encode PARAMS ((HOST_WIDE_INT *, |
05bccae2 RK |
56 | unsigned HOST_WIDE_INT, |
57 | HOST_WIDE_INT)); | |
711d877c | 58 | static void decode PARAMS ((HOST_WIDE_INT *, |
05bccae2 | 59 | unsigned HOST_WIDE_INT *, |
711d877c | 60 | HOST_WIDE_INT *)); |
94aca342 ZW |
61 | #ifndef REAL_ARITHMETIC |
62 | static void exact_real_inverse_1 PARAMS ((PTR)); | |
63 | #endif | |
711d877c KG |
64 | static tree negate_expr PARAMS ((tree)); |
65 | static tree split_tree PARAMS ((tree, enum tree_code, tree *, tree *, | |
66 | int)); | |
67 | static tree associate_trees PARAMS ((tree, tree, enum tree_code, tree)); | |
68 | static tree int_const_binop PARAMS ((enum tree_code, tree, tree, int, int)); | |
69 | static void const_binop_1 PARAMS ((PTR)); | |
70 | static tree const_binop PARAMS ((enum tree_code, tree, tree, int)); | |
71 | static void fold_convert_1 PARAMS ((PTR)); | |
72 | static tree fold_convert PARAMS ((tree, tree)); | |
73 | static enum tree_code invert_tree_comparison PARAMS ((enum tree_code)); | |
74 | static enum tree_code swap_tree_comparison PARAMS ((enum tree_code)); | |
75 | static int truth_value_p PARAMS ((enum tree_code)); | |
76 | static int operand_equal_for_comparison_p PARAMS ((tree, tree, tree)); | |
77 | static int twoval_comparison_p PARAMS ((tree, tree *, tree *, int *)); | |
78 | static tree eval_subst PARAMS ((tree, tree, tree, tree, tree)); | |
79 | static tree omit_one_operand PARAMS ((tree, tree, tree)); | |
80 | static tree pedantic_omit_one_operand PARAMS ((tree, tree, tree)); | |
81 | static tree distribute_bit_expr PARAMS ((enum tree_code, tree, tree, tree)); | |
82 | static tree make_bit_field_ref PARAMS ((tree, tree, int, int, int)); | |
83 | static tree optimize_bit_field_compare PARAMS ((enum tree_code, tree, | |
84 | tree, tree)); | |
770ae6cc RK |
85 | static tree decode_field_reference PARAMS ((tree, HOST_WIDE_INT *, |
86 | HOST_WIDE_INT *, | |
711d877c KG |
87 | enum machine_mode *, int *, |
88 | int *, tree *, tree *)); | |
89 | static int all_ones_mask_p PARAMS ((tree, int)); | |
90 | static int simple_operand_p PARAMS ((tree)); | |
91 | static tree range_binop PARAMS ((enum tree_code, tree, tree, int, | |
92 | tree, int)); | |
93 | static tree make_range PARAMS ((tree, int *, tree *, tree *)); | |
94 | static tree build_range_check PARAMS ((tree, tree, int, tree, tree)); | |
95 | static int merge_ranges PARAMS ((int *, tree *, tree *, int, tree, tree, | |
ebde8a27 | 96 | int, tree, tree)); |
711d877c KG |
97 | static tree fold_range_test PARAMS ((tree)); |
98 | static tree unextend PARAMS ((tree, int, int, tree)); | |
99 | static tree fold_truthop PARAMS ((enum tree_code, tree, tree, tree)); | |
100 | static tree optimize_minmax_comparison PARAMS ((tree)); | |
101 | static tree extract_muldiv PARAMS ((tree, tree, enum tree_code, tree)); | |
102 | static tree strip_compound_expr PARAMS ((tree, tree)); | |
103 | static int multiple_of_p PARAMS ((tree, tree, tree)); | |
104 | static tree constant_boolean_node PARAMS ((int, tree)); | |
105 | static int count_cond PARAMS ((tree, int)); | |
68626d4f MM |
106 | static tree fold_binary_op_with_conditional_arg |
107 | PARAMS ((enum tree_code, tree, tree, tree, int)); | |
108 | ||
d35357ed RS |
109 | #ifndef BRANCH_COST |
110 | #define BRANCH_COST 1 | |
111 | #endif | |
fe3e8e40 | 112 | |
5f6d3823 DP |
113 | #if defined(HOST_EBCDIC) |
114 | /* bit 8 is significant in EBCDIC */ | |
115 | #define CHARMASK 0xff | |
116 | #else | |
117 | #define CHARMASK 0x7f | |
118 | #endif | |
119 | ||
d4b60170 RK |
120 | /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring |
121 | overflow. Suppose A, B and SUM have the same respective signs as A1, B1, | |
122 | and SUM1. Then this yields nonzero if overflow occurred during the | |
123 | addition. | |
124 | ||
125 | Overflow occurs if A and B have the same sign, but A and SUM differ in | |
126 | sign. Use `^' to test whether signs differ, and `< 0' to isolate the | |
127 | sign. */ | |
128 | #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0) | |
6d716ca8 | 129 | \f |
906c4e36 | 130 | /* To do constant folding on INTEGER_CST nodes requires two-word arithmetic. |
37bdb7e3 | 131 | We do that by representing the two-word integer in 4 words, with only |
d4b60170 RK |
132 | HOST_BITS_PER_WIDE_INT / 2 bits stored in each word, as a positive |
133 | number. The value of the word is LOWPART + HIGHPART * BASE. */ | |
37bdb7e3 TG |
134 | |
135 | #define LOWPART(x) \ | |
d4b60170 | 136 | ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)) - 1)) |
37bdb7e3 | 137 | #define HIGHPART(x) \ |
d4b60170 RK |
138 | ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT / 2) |
139 | #define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT / 2) | |
6d716ca8 | 140 | |
37bdb7e3 | 141 | /* Unpack a two-word integer into 4 words. |
906c4e36 | 142 | LOW and HI are the integer, as two `HOST_WIDE_INT' pieces. |
37bdb7e3 | 143 | WORDS points to the array of HOST_WIDE_INTs. */ |
6d716ca8 RS |
144 | |
145 | static void | |
37bdb7e3 TG |
146 | encode (words, low, hi) |
147 | HOST_WIDE_INT *words; | |
05bccae2 RK |
148 | unsigned HOST_WIDE_INT low; |
149 | HOST_WIDE_INT hi; | |
6d716ca8 | 150 | { |
37bdb7e3 TG |
151 | words[0] = LOWPART (low); |
152 | words[1] = HIGHPART (low); | |
153 | words[2] = LOWPART (hi); | |
154 | words[3] = HIGHPART (hi); | |
6d716ca8 RS |
155 | } |
156 | ||
37bdb7e3 TG |
157 | /* Pack an array of 4 words into a two-word integer. |
158 | WORDS points to the array of words. | |
906c4e36 | 159 | The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */ |
6d716ca8 RS |
160 | |
161 | static void | |
37bdb7e3 TG |
162 | decode (words, low, hi) |
163 | HOST_WIDE_INT *words; | |
05bccae2 RK |
164 | unsigned HOST_WIDE_INT *low; |
165 | HOST_WIDE_INT *hi; | |
6d716ca8 | 166 | { |
d4b60170 RK |
167 | *low = words[0] + words[1] * BASE; |
168 | *hi = words[2] + words[3] * BASE; | |
6d716ca8 RS |
169 | } |
170 | \f | |
d4b60170 RK |
171 | /* Make the integer constant T valid for its type by setting to 0 or 1 all |
172 | the bits in the constant that don't belong in the type. | |
173 | ||
174 | Return 1 if a signed overflow occurs, 0 otherwise. If OVERFLOW is | |
175 | nonzero, a signed overflow has already occurred in calculating T, so | |
176 | propagate it. | |
649ff3b4 RK |
177 | |
178 | Make the real constant T valid for its type by calling CHECK_FLOAT_VALUE, | |
179 | if it exists. */ | |
6d716ca8 | 180 | |
e0f776fb RS |
181 | int |
182 | force_fit_type (t, overflow) | |
6d716ca8 | 183 | tree t; |
e0f776fb | 184 | int overflow; |
6d716ca8 | 185 | { |
05bccae2 RK |
186 | unsigned HOST_WIDE_INT low; |
187 | HOST_WIDE_INT high; | |
188 | unsigned int prec; | |
6d716ca8 | 189 | |
649ff3b4 RK |
190 | if (TREE_CODE (t) == REAL_CST) |
191 | { | |
192 | #ifdef CHECK_FLOAT_VALUE | |
193 | CHECK_FLOAT_VALUE (TYPE_MODE (TREE_TYPE (t)), TREE_REAL_CST (t), | |
194 | overflow); | |
195 | #endif | |
196 | return overflow; | |
197 | } | |
198 | ||
199 | else if (TREE_CODE (t) != INTEGER_CST) | |
ef2bf0c0 RS |
200 | return overflow; |
201 | ||
202 | low = TREE_INT_CST_LOW (t); | |
203 | high = TREE_INT_CST_HIGH (t); | |
42f769c1 | 204 | |
e5e809f4 | 205 | if (POINTER_TYPE_P (TREE_TYPE (t))) |
6d716ca8 | 206 | prec = POINTER_SIZE; |
ef2bf0c0 RS |
207 | else |
208 | prec = TYPE_PRECISION (TREE_TYPE (t)); | |
6d716ca8 RS |
209 | |
210 | /* First clear all bits that are beyond the type's precision. */ | |
211 | ||
906c4e36 | 212 | if (prec == 2 * HOST_BITS_PER_WIDE_INT) |
6d716ca8 | 213 | ; |
906c4e36 | 214 | else if (prec > HOST_BITS_PER_WIDE_INT) |
d4b60170 RK |
215 | TREE_INT_CST_HIGH (t) |
216 | &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT)); | |
6d716ca8 RS |
217 | else |
218 | { | |
219 | TREE_INT_CST_HIGH (t) = 0; | |
906c4e36 | 220 | if (prec < HOST_BITS_PER_WIDE_INT) |
05bccae2 | 221 | TREE_INT_CST_LOW (t) &= ~((unsigned HOST_WIDE_INT) (-1) << prec); |
6d716ca8 RS |
222 | } |
223 | ||
44475138 RK |
224 | /* Unsigned types do not suffer sign extension or overflow unless they |
225 | are a sizetype. */ | |
226 | if (TREE_UNSIGNED (TREE_TYPE (t)) | |
227 | && ! (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE | |
228 | && TYPE_IS_SIZETYPE (TREE_TYPE (t)))) | |
a7a05640 | 229 | return overflow; |
6d716ca8 | 230 | |
e0f776fb RS |
231 | /* If the value's sign bit is set, extend the sign. */ |
232 | if (prec != 2 * HOST_BITS_PER_WIDE_INT | |
906c4e36 | 233 | && (prec > HOST_BITS_PER_WIDE_INT |
05bccae2 RK |
234 | ? 0 != (TREE_INT_CST_HIGH (t) |
235 | & ((HOST_WIDE_INT) 1 | |
236 | << (prec - HOST_BITS_PER_WIDE_INT - 1))) | |
237 | : 0 != (TREE_INT_CST_LOW (t) | |
238 | & ((unsigned HOST_WIDE_INT) 1 << (prec - 1))))) | |
6d716ca8 RS |
239 | { |
240 | /* Value is negative: | |
241 | set to 1 all the bits that are outside this type's precision. */ | |
906c4e36 | 242 | if (prec > HOST_BITS_PER_WIDE_INT) |
d4b60170 RK |
243 | TREE_INT_CST_HIGH (t) |
244 | |= ((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT)); | |
6d716ca8 RS |
245 | else |
246 | { | |
247 | TREE_INT_CST_HIGH (t) = -1; | |
906c4e36 | 248 | if (prec < HOST_BITS_PER_WIDE_INT) |
05bccae2 | 249 | TREE_INT_CST_LOW (t) |= ((unsigned HOST_WIDE_INT) (-1) << prec); |
6d716ca8 RS |
250 | } |
251 | } | |
e0f776fb | 252 | |
d4b60170 | 253 | /* Return nonzero if signed overflow occurred. */ |
e0f776fb RS |
254 | return |
255 | ((overflow | (low ^ TREE_INT_CST_LOW (t)) | (high ^ TREE_INT_CST_HIGH (t))) | |
256 | != 0); | |
6d716ca8 RS |
257 | } |
258 | \f | |
906c4e36 RK |
259 | /* Add two doubleword integers with doubleword result. |
260 | Each argument is given as two `HOST_WIDE_INT' pieces. | |
6d716ca8 | 261 | One argument is L1 and H1; the other, L2 and H2. |
37bdb7e3 | 262 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 263 | |
fe3e8e40 | 264 | int |
6d716ca8 | 265 | add_double (l1, h1, l2, h2, lv, hv) |
05bccae2 RK |
266 | unsigned HOST_WIDE_INT l1, l2; |
267 | HOST_WIDE_INT h1, h2; | |
268 | unsigned HOST_WIDE_INT *lv; | |
269 | HOST_WIDE_INT *hv; | |
6d716ca8 | 270 | { |
05bccae2 RK |
271 | unsigned HOST_WIDE_INT l; |
272 | HOST_WIDE_INT h; | |
6d716ca8 | 273 | |
37bdb7e3 | 274 | l = l1 + l2; |
05bccae2 | 275 | h = h1 + h2 + (l < l1); |
6d716ca8 | 276 | |
37bdb7e3 TG |
277 | *lv = l; |
278 | *hv = h; | |
d4b60170 | 279 | return OVERFLOW_SUM_SIGN (h1, h2, h); |
6d716ca8 RS |
280 | } |
281 | ||
906c4e36 | 282 | /* Negate a doubleword integer with doubleword result. |
fe3e8e40 | 283 | Return nonzero if the operation overflows, assuming it's signed. |
906c4e36 | 284 | The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1. |
37bdb7e3 | 285 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 286 | |
fe3e8e40 | 287 | int |
6d716ca8 | 288 | neg_double (l1, h1, lv, hv) |
05bccae2 RK |
289 | unsigned HOST_WIDE_INT l1; |
290 | HOST_WIDE_INT h1; | |
291 | unsigned HOST_WIDE_INT *lv; | |
292 | HOST_WIDE_INT *hv; | |
6d716ca8 RS |
293 | { |
294 | if (l1 == 0) | |
295 | { | |
296 | *lv = 0; | |
297 | *hv = - h1; | |
e0f776fb | 298 | return (*hv & h1) < 0; |
6d716ca8 RS |
299 | } |
300 | else | |
301 | { | |
b6cc0a72 KH |
302 | *lv = -l1; |
303 | *hv = ~h1; | |
fe3e8e40 | 304 | return 0; |
6d716ca8 RS |
305 | } |
306 | } | |
307 | \f | |
906c4e36 | 308 | /* Multiply two doubleword integers with doubleword result. |
fe3e8e40 | 309 | Return nonzero if the operation overflows, assuming it's signed. |
906c4e36 | 310 | Each argument is given as two `HOST_WIDE_INT' pieces. |
6d716ca8 | 311 | One argument is L1 and H1; the other, L2 and H2. |
37bdb7e3 | 312 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 313 | |
fe3e8e40 | 314 | int |
6d716ca8 | 315 | mul_double (l1, h1, l2, h2, lv, hv) |
05bccae2 RK |
316 | unsigned HOST_WIDE_INT l1, l2; |
317 | HOST_WIDE_INT h1, h2; | |
318 | unsigned HOST_WIDE_INT *lv; | |
319 | HOST_WIDE_INT *hv; | |
6d716ca8 | 320 | { |
37bdb7e3 TG |
321 | HOST_WIDE_INT arg1[4]; |
322 | HOST_WIDE_INT arg2[4]; | |
323 | HOST_WIDE_INT prod[4 * 2]; | |
324 | register unsigned HOST_WIDE_INT carry; | |
6d716ca8 | 325 | register int i, j, k; |
05bccae2 RK |
326 | unsigned HOST_WIDE_INT toplow, neglow; |
327 | HOST_WIDE_INT tophigh, neghigh; | |
6d716ca8 | 328 | |
6d716ca8 RS |
329 | encode (arg1, l1, h1); |
330 | encode (arg2, l2, h2); | |
331 | ||
961192e1 | 332 | memset ((char *) prod, 0, sizeof prod); |
6d716ca8 | 333 | |
37bdb7e3 TG |
334 | for (i = 0; i < 4; i++) |
335 | { | |
336 | carry = 0; | |
337 | for (j = 0; j < 4; j++) | |
338 | { | |
339 | k = i + j; | |
340 | /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */ | |
341 | carry += arg1[i] * arg2[j]; | |
342 | /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */ | |
343 | carry += prod[k]; | |
344 | prod[k] = LOWPART (carry); | |
345 | carry = HIGHPART (carry); | |
346 | } | |
347 | prod[i + 4] = carry; | |
348 | } | |
6d716ca8 | 349 | |
37bdb7e3 | 350 | decode (prod, lv, hv); /* This ignores prod[4] through prod[4*2-1] */ |
fe3e8e40 RS |
351 | |
352 | /* Check for overflow by calculating the top half of the answer in full; | |
353 | it should agree with the low half's sign bit. */ | |
b6cc0a72 | 354 | decode (prod + 4, &toplow, &tophigh); |
fe3e8e40 RS |
355 | if (h1 < 0) |
356 | { | |
357 | neg_double (l2, h2, &neglow, &neghigh); | |
358 | add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh); | |
359 | } | |
360 | if (h2 < 0) | |
361 | { | |
362 | neg_double (l1, h1, &neglow, &neghigh); | |
363 | add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh); | |
364 | } | |
365 | return (*hv < 0 ? ~(toplow & tophigh) : toplow | tophigh) != 0; | |
6d716ca8 RS |
366 | } |
367 | \f | |
906c4e36 | 368 | /* Shift the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 RS |
369 | keeping only PREC bits of result. |
370 | Shift right if COUNT is negative. | |
371 | ARITH nonzero specifies arithmetic shifting; otherwise use logical shift. | |
906c4e36 | 372 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 373 | |
e0f776fb | 374 | void |
6d716ca8 | 375 | lshift_double (l1, h1, count, prec, lv, hv, arith) |
05bccae2 RK |
376 | unsigned HOST_WIDE_INT l1; |
377 | HOST_WIDE_INT h1, count; | |
378 | unsigned int prec; | |
379 | unsigned HOST_WIDE_INT *lv; | |
380 | HOST_WIDE_INT *hv; | |
6d716ca8 RS |
381 | int arith; |
382 | { | |
6d716ca8 RS |
383 | if (count < 0) |
384 | { | |
b6cc0a72 | 385 | rshift_double (l1, h1, -count, prec, lv, hv, arith); |
e0f776fb | 386 | return; |
6d716ca8 | 387 | } |
b6cc0a72 | 388 | |
3d1877b1 RK |
389 | #ifdef SHIFT_COUNT_TRUNCATED |
390 | if (SHIFT_COUNT_TRUNCATED) | |
391 | count %= prec; | |
392 | #endif | |
6d716ca8 | 393 | |
cb0a34c4 JW |
394 | if (count >= 2 * HOST_BITS_PER_WIDE_INT) |
395 | { | |
396 | /* Shifting by the host word size is undefined according to the | |
397 | ANSI standard, so we must handle this as a special case. */ | |
398 | *hv = 0; | |
399 | *lv = 0; | |
400 | } | |
401 | else if (count >= HOST_BITS_PER_WIDE_INT) | |
6d716ca8 | 402 | { |
05bccae2 | 403 | *hv = l1 << (count - HOST_BITS_PER_WIDE_INT); |
37bdb7e3 TG |
404 | *lv = 0; |
405 | } | |
406 | else | |
407 | { | |
408 | *hv = (((unsigned HOST_WIDE_INT) h1 << count) | |
05bccae2 RK |
409 | | (l1 >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1)); |
410 | *lv = l1 << count; | |
6d716ca8 | 411 | } |
6d716ca8 RS |
412 | } |
413 | ||
906c4e36 | 414 | /* Shift the doubleword integer in L1, H1 right by COUNT places |
6d716ca8 RS |
415 | keeping only PREC bits of result. COUNT must be positive. |
416 | ARITH nonzero specifies arithmetic shifting; otherwise use logical shift. | |
906c4e36 | 417 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
418 | |
419 | void | |
420 | rshift_double (l1, h1, count, prec, lv, hv, arith) | |
05bccae2 RK |
421 | unsigned HOST_WIDE_INT l1; |
422 | HOST_WIDE_INT h1, count; | |
423 | unsigned int prec ATTRIBUTE_UNUSED; | |
424 | unsigned HOST_WIDE_INT *lv; | |
425 | HOST_WIDE_INT *hv; | |
6d716ca8 RS |
426 | int arith; |
427 | { | |
37bdb7e3 | 428 | unsigned HOST_WIDE_INT signmask; |
05bccae2 | 429 | |
37bdb7e3 TG |
430 | signmask = (arith |
431 | ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1)) | |
432 | : 0); | |
6d716ca8 | 433 | |
3d1877b1 RK |
434 | #ifdef SHIFT_COUNT_TRUNCATED |
435 | if (SHIFT_COUNT_TRUNCATED) | |
436 | count %= prec; | |
437 | #endif | |
6d716ca8 | 438 | |
cb0a34c4 JW |
439 | if (count >= 2 * HOST_BITS_PER_WIDE_INT) |
440 | { | |
441 | /* Shifting by the host word size is undefined according to the | |
442 | ANSI standard, so we must handle this as a special case. */ | |
443 | *hv = signmask; | |
444 | *lv = signmask; | |
445 | } | |
446 | else if (count >= HOST_BITS_PER_WIDE_INT) | |
6d716ca8 | 447 | { |
37bdb7e3 | 448 | *hv = signmask; |
2fde567e KG |
449 | *lv = ((signmask << (2 * HOST_BITS_PER_WIDE_INT - count - 1) << 1) |
450 | | ((unsigned HOST_WIDE_INT) h1 >> (count - HOST_BITS_PER_WIDE_INT))); | |
37bdb7e3 TG |
451 | } |
452 | else | |
453 | { | |
05bccae2 | 454 | *lv = ((l1 >> count) |
2fde567e KG |
455 | | ((unsigned HOST_WIDE_INT) h1 << (HOST_BITS_PER_WIDE_INT - count - 1) << 1)); |
456 | *hv = ((signmask << (HOST_BITS_PER_WIDE_INT - count)) | |
37bdb7e3 | 457 | | ((unsigned HOST_WIDE_INT) h1 >> count)); |
6d716ca8 | 458 | } |
6d716ca8 RS |
459 | } |
460 | \f | |
37bdb7e3 | 461 | /* Rotate the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 RS |
462 | keeping only PREC bits of result. |
463 | Rotate right if COUNT is negative. | |
906c4e36 | 464 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
465 | |
466 | void | |
467 | lrotate_double (l1, h1, count, prec, lv, hv) | |
05bccae2 RK |
468 | unsigned HOST_WIDE_INT l1; |
469 | HOST_WIDE_INT h1, count; | |
470 | unsigned int prec; | |
471 | unsigned HOST_WIDE_INT *lv; | |
472 | HOST_WIDE_INT *hv; | |
6d716ca8 | 473 | { |
05bccae2 RK |
474 | unsigned HOST_WIDE_INT s1l, s2l; |
475 | HOST_WIDE_INT s1h, s2h; | |
6d716ca8 | 476 | |
4d39710e | 477 | count %= prec; |
6d716ca8 | 478 | if (count < 0) |
4d39710e | 479 | count += prec; |
6d716ca8 | 480 | |
4d39710e RK |
481 | lshift_double (l1, h1, count, prec, &s1l, &s1h, 0); |
482 | rshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0); | |
483 | *lv = s1l | s2l; | |
484 | *hv = s1h | s2h; | |
6d716ca8 RS |
485 | } |
486 | ||
906c4e36 | 487 | /* Rotate the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 | 488 | keeping only PREC bits of result. COUNT must be positive. |
906c4e36 | 489 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
490 | |
491 | void | |
492 | rrotate_double (l1, h1, count, prec, lv, hv) | |
05bccae2 RK |
493 | unsigned HOST_WIDE_INT l1; |
494 | HOST_WIDE_INT h1, count; | |
495 | unsigned int prec; | |
496 | unsigned HOST_WIDE_INT *lv; | |
497 | HOST_WIDE_INT *hv; | |
6d716ca8 | 498 | { |
05bccae2 RK |
499 | unsigned HOST_WIDE_INT s1l, s2l; |
500 | HOST_WIDE_INT s1h, s2h; | |
6d716ca8 | 501 | |
4d39710e RK |
502 | count %= prec; |
503 | if (count < 0) | |
504 | count += prec; | |
6d716ca8 | 505 | |
4d39710e RK |
506 | rshift_double (l1, h1, count, prec, &s1l, &s1h, 0); |
507 | lshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0); | |
508 | *lv = s1l | s2l; | |
509 | *hv = s1h | s2h; | |
6d716ca8 RS |
510 | } |
511 | \f | |
906c4e36 | 512 | /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN |
6d716ca8 RS |
513 | for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM). |
514 | CODE is a tree code for a kind of division, one of | |
515 | TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR | |
516 | or EXACT_DIV_EXPR | |
fe3e8e40 RS |
517 | It controls how the quotient is rounded to a integer. |
518 | Return nonzero if the operation overflows. | |
6d716ca8 RS |
519 | UNS nonzero says do unsigned division. */ |
520 | ||
dbb5b3ce | 521 | int |
6d716ca8 RS |
522 | div_and_round_double (code, uns, |
523 | lnum_orig, hnum_orig, lden_orig, hden_orig, | |
524 | lquo, hquo, lrem, hrem) | |
525 | enum tree_code code; | |
526 | int uns; | |
05bccae2 RK |
527 | unsigned HOST_WIDE_INT lnum_orig; /* num == numerator == dividend */ |
528 | HOST_WIDE_INT hnum_orig; | |
529 | unsigned HOST_WIDE_INT lden_orig; /* den == denominator == divisor */ | |
530 | HOST_WIDE_INT hden_orig; | |
531 | unsigned HOST_WIDE_INT *lquo, *lrem; | |
532 | HOST_WIDE_INT *hquo, *hrem; | |
6d716ca8 RS |
533 | { |
534 | int quo_neg = 0; | |
37bdb7e3 TG |
535 | HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */ |
536 | HOST_WIDE_INT den[4], quo[4]; | |
537 | register int i, j; | |
538 | unsigned HOST_WIDE_INT work; | |
05bccae2 RK |
539 | unsigned HOST_WIDE_INT carry = 0; |
540 | unsigned HOST_WIDE_INT lnum = lnum_orig; | |
b8eb43a2 | 541 | HOST_WIDE_INT hnum = hnum_orig; |
05bccae2 | 542 | unsigned HOST_WIDE_INT lden = lden_orig; |
b8eb43a2 | 543 | HOST_WIDE_INT hden = hden_orig; |
fe3e8e40 | 544 | int overflow = 0; |
6d716ca8 | 545 | |
05bccae2 | 546 | if (hden == 0 && lden == 0) |
956d6950 | 547 | overflow = 1, lden = 1; |
6d716ca8 RS |
548 | |
549 | /* calculate quotient sign and convert operands to unsigned. */ | |
b6cc0a72 | 550 | if (!uns) |
6d716ca8 | 551 | { |
fe3e8e40 | 552 | if (hnum < 0) |
6d716ca8 RS |
553 | { |
554 | quo_neg = ~ quo_neg; | |
fe3e8e40 | 555 | /* (minimum integer) / (-1) is the only overflow case. */ |
05bccae2 RK |
556 | if (neg_double (lnum, hnum, &lnum, &hnum) |
557 | && ((HOST_WIDE_INT) lden & hden) == -1) | |
fe3e8e40 | 558 | overflow = 1; |
6d716ca8 | 559 | } |
b6cc0a72 | 560 | if (hden < 0) |
6d716ca8 RS |
561 | { |
562 | quo_neg = ~ quo_neg; | |
fe3e8e40 | 563 | neg_double (lden, hden, &lden, &hden); |
6d716ca8 RS |
564 | } |
565 | } | |
566 | ||
567 | if (hnum == 0 && hden == 0) | |
568 | { /* single precision */ | |
569 | *hquo = *hrem = 0; | |
88ee2651 | 570 | /* This unsigned division rounds toward zero. */ |
05bccae2 | 571 | *lquo = lnum / lden; |
6d716ca8 RS |
572 | goto finish_up; |
573 | } | |
574 | ||
575 | if (hnum == 0) | |
576 | { /* trivial case: dividend < divisor */ | |
577 | /* hden != 0 already checked. */ | |
578 | *hquo = *lquo = 0; | |
579 | *hrem = hnum; | |
580 | *lrem = lnum; | |
581 | goto finish_up; | |
582 | } | |
583 | ||
961192e1 | 584 | memset ((char *) quo, 0, sizeof quo); |
6d716ca8 | 585 | |
961192e1 JM |
586 | memset ((char *) num, 0, sizeof num); /* to zero 9th element */ |
587 | memset ((char *) den, 0, sizeof den); | |
6d716ca8 | 588 | |
b6cc0a72 | 589 | encode (num, lnum, hnum); |
6d716ca8 RS |
590 | encode (den, lden, hden); |
591 | ||
37bdb7e3 | 592 | /* Special code for when the divisor < BASE. */ |
05bccae2 | 593 | if (hden == 0 && lden < (unsigned HOST_WIDE_INT) BASE) |
37bdb7e3 | 594 | { |
6d716ca8 | 595 | /* hnum != 0 already checked. */ |
37bdb7e3 | 596 | for (i = 4 - 1; i >= 0; i--) |
6d716ca8 | 597 | { |
37bdb7e3 | 598 | work = num[i] + carry * BASE; |
05bccae2 RK |
599 | quo[i] = work / lden; |
600 | carry = work % lden; | |
6d716ca8 RS |
601 | } |
602 | } | |
37bdb7e3 TG |
603 | else |
604 | { | |
605 | /* Full double precision division, | |
606 | with thanks to Don Knuth's "Seminumerical Algorithms". */ | |
05bccae2 RK |
607 | int num_hi_sig, den_hi_sig; |
608 | unsigned HOST_WIDE_INT quo_est, scale; | |
6d716ca8 | 609 | |
05bccae2 | 610 | /* Find the highest non-zero divisor digit. */ |
b6cc0a72 KH |
611 | for (i = 4 - 1;; i--) |
612 | if (den[i] != 0) | |
613 | { | |
614 | den_hi_sig = i; | |
615 | break; | |
616 | } | |
37bdb7e3 | 617 | |
05bccae2 RK |
618 | /* Insure that the first digit of the divisor is at least BASE/2. |
619 | This is required by the quotient digit estimation algorithm. */ | |
6d716ca8 | 620 | |
05bccae2 RK |
621 | scale = BASE / (den[den_hi_sig] + 1); |
622 | if (scale > 1) | |
623 | { /* scale divisor and dividend */ | |
624 | carry = 0; | |
625 | for (i = 0; i <= 4 - 1; i++) | |
626 | { | |
627 | work = (num[i] * scale) + carry; | |
628 | num[i] = LOWPART (work); | |
629 | carry = HIGHPART (work); | |
630 | } | |
6d716ca8 | 631 | |
05bccae2 RK |
632 | num[4] = carry; |
633 | carry = 0; | |
634 | for (i = 0; i <= 4 - 1; i++) | |
635 | { | |
636 | work = (den[i] * scale) + carry; | |
637 | den[i] = LOWPART (work); | |
638 | carry = HIGHPART (work); | |
639 | if (den[i] != 0) den_hi_sig = i; | |
640 | } | |
641 | } | |
6d716ca8 | 642 | |
05bccae2 | 643 | num_hi_sig = 4; |
6d716ca8 | 644 | |
05bccae2 RK |
645 | /* Main loop */ |
646 | for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--) | |
6d716ca8 | 647 | { |
05bccae2 RK |
648 | /* Guess the next quotient digit, quo_est, by dividing the first |
649 | two remaining dividend digits by the high order quotient digit. | |
650 | quo_est is never low and is at most 2 high. */ | |
651 | unsigned HOST_WIDE_INT tmp; | |
652 | ||
653 | num_hi_sig = i + den_hi_sig + 1; | |
654 | work = num[num_hi_sig] * BASE + num[num_hi_sig - 1]; | |
655 | if (num[num_hi_sig] != den[den_hi_sig]) | |
656 | quo_est = work / den[den_hi_sig]; | |
657 | else | |
658 | quo_est = BASE - 1; | |
6d716ca8 | 659 | |
05bccae2 RK |
660 | /* Refine quo_est so it's usually correct, and at most one high. */ |
661 | tmp = work - quo_est * den[den_hi_sig]; | |
662 | if (tmp < BASE | |
663 | && (den[den_hi_sig - 1] * quo_est | |
664 | > (tmp * BASE + num[num_hi_sig - 2]))) | |
665 | quo_est--; | |
6d716ca8 | 666 | |
05bccae2 RK |
667 | /* Try QUO_EST as the quotient digit, by multiplying the |
668 | divisor by QUO_EST and subtracting from the remaining dividend. | |
669 | Keep in mind that QUO_EST is the I - 1st digit. */ | |
670 | ||
671 | carry = 0; | |
6d716ca8 RS |
672 | for (j = 0; j <= den_hi_sig; j++) |
673 | { | |
05bccae2 | 674 | work = quo_est * den[j] + carry; |
37bdb7e3 | 675 | carry = HIGHPART (work); |
05bccae2 | 676 | work = num[i + j] - LOWPART (work); |
37bdb7e3 | 677 | num[i + j] = LOWPART (work); |
05bccae2 | 678 | carry += HIGHPART (work) != 0; |
6d716ca8 | 679 | } |
6d716ca8 | 680 | |
05bccae2 RK |
681 | /* If quo_est was high by one, then num[i] went negative and |
682 | we need to correct things. */ | |
683 | if (num[num_hi_sig] < carry) | |
684 | { | |
685 | quo_est--; | |
686 | carry = 0; /* add divisor back in */ | |
687 | for (j = 0; j <= den_hi_sig; j++) | |
688 | { | |
689 | work = num[i + j] + den[j] + carry; | |
690 | carry = HIGHPART (work); | |
691 | num[i + j] = LOWPART (work); | |
692 | } | |
693 | ||
694 | num [num_hi_sig] += carry; | |
695 | } | |
696 | ||
697 | /* Store the quotient digit. */ | |
698 | quo[i] = quo_est; | |
699 | } | |
6d716ca8 | 700 | } |
6d716ca8 RS |
701 | |
702 | decode (quo, lquo, hquo); | |
703 | ||
704 | finish_up: | |
705 | /* if result is negative, make it so. */ | |
706 | if (quo_neg) | |
707 | neg_double (*lquo, *hquo, lquo, hquo); | |
708 | ||
709 | /* compute trial remainder: rem = num - (quo * den) */ | |
710 | mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem); | |
711 | neg_double (*lrem, *hrem, lrem, hrem); | |
712 | add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem); | |
713 | ||
714 | switch (code) | |
715 | { | |
716 | case TRUNC_DIV_EXPR: | |
717 | case TRUNC_MOD_EXPR: /* round toward zero */ | |
718 | case EXACT_DIV_EXPR: /* for this one, it shouldn't matter */ | |
fe3e8e40 | 719 | return overflow; |
6d716ca8 RS |
720 | |
721 | case FLOOR_DIV_EXPR: | |
722 | case FLOOR_MOD_EXPR: /* round toward negative infinity */ | |
723 | if (quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio < 0 && rem != 0 */ | |
724 | { | |
725 | /* quo = quo - 1; */ | |
906c4e36 RK |
726 | add_double (*lquo, *hquo, (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, |
727 | lquo, hquo); | |
6d716ca8 | 728 | } |
05bccae2 RK |
729 | else |
730 | return overflow; | |
6d716ca8 RS |
731 | break; |
732 | ||
733 | case CEIL_DIV_EXPR: | |
734 | case CEIL_MOD_EXPR: /* round toward positive infinity */ | |
735 | if (!quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio > 0 && rem != 0 */ | |
736 | { | |
906c4e36 RK |
737 | add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0, |
738 | lquo, hquo); | |
6d716ca8 | 739 | } |
05bccae2 RK |
740 | else |
741 | return overflow; | |
6d716ca8 | 742 | break; |
b6cc0a72 | 743 | |
6d716ca8 RS |
744 | case ROUND_DIV_EXPR: |
745 | case ROUND_MOD_EXPR: /* round to closest integer */ | |
746 | { | |
05bccae2 RK |
747 | unsigned HOST_WIDE_INT labs_rem = *lrem; |
748 | HOST_WIDE_INT habs_rem = *hrem; | |
749 | unsigned HOST_WIDE_INT labs_den = lden, ltwice; | |
750 | HOST_WIDE_INT habs_den = hden, htwice; | |
751 | ||
752 | /* Get absolute values */ | |
753 | if (*hrem < 0) | |
754 | neg_double (*lrem, *hrem, &labs_rem, &habs_rem); | |
755 | if (hden < 0) | |
756 | neg_double (lden, hden, &labs_den, &habs_den); | |
757 | ||
758 | /* If (2 * abs (lrem) >= abs (lden)) */ | |
906c4e36 RK |
759 | mul_double ((HOST_WIDE_INT) 2, (HOST_WIDE_INT) 0, |
760 | labs_rem, habs_rem, <wice, &htwice); | |
05bccae2 | 761 | |
906c4e36 RK |
762 | if (((unsigned HOST_WIDE_INT) habs_den |
763 | < (unsigned HOST_WIDE_INT) htwice) | |
764 | || (((unsigned HOST_WIDE_INT) habs_den | |
765 | == (unsigned HOST_WIDE_INT) htwice) | |
05bccae2 | 766 | && (labs_den < ltwice))) |
6d716ca8 RS |
767 | { |
768 | if (*hquo < 0) | |
769 | /* quo = quo - 1; */ | |
906c4e36 RK |
770 | add_double (*lquo, *hquo, |
771 | (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, lquo, hquo); | |
6d716ca8 RS |
772 | else |
773 | /* quo = quo + 1; */ | |
906c4e36 RK |
774 | add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0, |
775 | lquo, hquo); | |
6d716ca8 | 776 | } |
05bccae2 RK |
777 | else |
778 | return overflow; | |
6d716ca8 RS |
779 | } |
780 | break; | |
781 | ||
782 | default: | |
783 | abort (); | |
784 | } | |
785 | ||
786 | /* compute true remainder: rem = num - (quo * den) */ | |
787 | mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem); | |
788 | neg_double (*lrem, *hrem, lrem, hrem); | |
789 | add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem); | |
fe3e8e40 | 790 | return overflow; |
6d716ca8 RS |
791 | } |
792 | \f | |
5008b8ae | 793 | #ifndef REAL_ARITHMETIC |
649ff3b4 RK |
794 | /* Effectively truncate a real value to represent the nearest possible value |
795 | in a narrower mode. The result is actually represented in the same data | |
796 | type as the argument, but its value is usually different. | |
797 | ||
798 | A trap may occur during the FP operations and it is the responsibility | |
799 | of the calling function to have a handler established. */ | |
5352b11a RS |
800 | |
801 | REAL_VALUE_TYPE | |
802 | real_value_truncate (mode, arg) | |
803 | enum machine_mode mode; | |
804 | REAL_VALUE_TYPE arg; | |
805 | { | |
649ff3b4 | 806 | return REAL_VALUE_TRUNCATE (mode, arg); |
5352b11a RS |
807 | } |
808 | ||
6d716ca8 RS |
809 | #if TARGET_FLOAT_FORMAT == IEEE_FLOAT_FORMAT |
810 | ||
811 | /* Check for infinity in an IEEE double precision number. */ | |
812 | ||
813 | int | |
814 | target_isinf (x) | |
815 | REAL_VALUE_TYPE x; | |
816 | { | |
817 | /* The IEEE 64-bit double format. */ | |
818 | union { | |
819 | REAL_VALUE_TYPE d; | |
820 | struct { | |
821 | unsigned sign : 1; | |
822 | unsigned exponent : 11; | |
823 | unsigned mantissa1 : 20; | |
824 | unsigned mantissa2; | |
825 | } little_endian; | |
826 | struct { | |
827 | unsigned mantissa2; | |
828 | unsigned mantissa1 : 20; | |
829 | unsigned exponent : 11; | |
830 | unsigned sign : 1; | |
b6cc0a72 | 831 | } big_endian; |
6d716ca8 RS |
832 | } u; |
833 | ||
834 | u.d = dconstm1; | |
835 | if (u.big_endian.sign == 1) | |
836 | { | |
837 | u.d = x; | |
838 | return (u.big_endian.exponent == 2047 | |
839 | && u.big_endian.mantissa1 == 0 | |
840 | && u.big_endian.mantissa2 == 0); | |
841 | } | |
842 | else | |
843 | { | |
844 | u.d = x; | |
845 | return (u.little_endian.exponent == 2047 | |
846 | && u.little_endian.mantissa1 == 0 | |
847 | && u.little_endian.mantissa2 == 0); | |
848 | } | |
849 | } | |
850 | ||
7d4d4d22 RS |
851 | /* Check whether an IEEE double precision number is a NaN. */ |
852 | ||
853 | int | |
854 | target_isnan (x) | |
855 | REAL_VALUE_TYPE x; | |
856 | { | |
857 | /* The IEEE 64-bit double format. */ | |
858 | union { | |
859 | REAL_VALUE_TYPE d; | |
860 | struct { | |
861 | unsigned sign : 1; | |
862 | unsigned exponent : 11; | |
863 | unsigned mantissa1 : 20; | |
864 | unsigned mantissa2; | |
865 | } little_endian; | |
866 | struct { | |
867 | unsigned mantissa2; | |
868 | unsigned mantissa1 : 20; | |
869 | unsigned exponent : 11; | |
870 | unsigned sign : 1; | |
b6cc0a72 | 871 | } big_endian; |
7d4d4d22 RS |
872 | } u; |
873 | ||
874 | u.d = dconstm1; | |
875 | if (u.big_endian.sign == 1) | |
876 | { | |
877 | u.d = x; | |
878 | return (u.big_endian.exponent == 2047 | |
879 | && (u.big_endian.mantissa1 != 0 | |
880 | || u.big_endian.mantissa2 != 0)); | |
881 | } | |
882 | else | |
883 | { | |
884 | u.d = x; | |
885 | return (u.little_endian.exponent == 2047 | |
886 | && (u.little_endian.mantissa1 != 0 | |
887 | || u.little_endian.mantissa2 != 0)); | |
888 | } | |
889 | } | |
890 | ||
c05a9b68 | 891 | /* Check for a negative IEEE double precision number. */ |
6d716ca8 RS |
892 | |
893 | int | |
c05a9b68 | 894 | target_negative (x) |
6d716ca8 RS |
895 | REAL_VALUE_TYPE x; |
896 | { | |
c05a9b68 RS |
897 | /* The IEEE 64-bit double format. */ |
898 | union { | |
899 | REAL_VALUE_TYPE d; | |
900 | struct { | |
901 | unsigned sign : 1; | |
902 | unsigned exponent : 11; | |
903 | unsigned mantissa1 : 20; | |
904 | unsigned mantissa2; | |
905 | } little_endian; | |
906 | struct { | |
907 | unsigned mantissa2; | |
908 | unsigned mantissa1 : 20; | |
909 | unsigned exponent : 11; | |
910 | unsigned sign : 1; | |
b6cc0a72 | 911 | } big_endian; |
c05a9b68 | 912 | } u; |
6d716ca8 | 913 | |
c05a9b68 RS |
914 | u.d = dconstm1; |
915 | if (u.big_endian.sign == 1) | |
916 | { | |
917 | u.d = x; | |
918 | return u.big_endian.sign; | |
919 | } | |
920 | else | |
921 | { | |
922 | u.d = x; | |
923 | return u.little_endian.sign; | |
924 | } | |
6d716ca8 RS |
925 | } |
926 | #else /* Target not IEEE */ | |
927 | ||
928 | /* Let's assume other float formats don't have infinity. | |
929 | (This can be overridden by redefining REAL_VALUE_ISINF.) */ | |
930 | ||
7762d54e | 931 | int |
6d716ca8 | 932 | target_isinf (x) |
962f1324 | 933 | REAL_VALUE_TYPE x ATTRIBUTE_UNUSED; |
6d716ca8 RS |
934 | { |
935 | return 0; | |
936 | } | |
937 | ||
7d4d4d22 RS |
938 | /* Let's assume other float formats don't have NaNs. |
939 | (This can be overridden by redefining REAL_VALUE_ISNAN.) */ | |
940 | ||
7762d54e | 941 | int |
7d4d4d22 | 942 | target_isnan (x) |
962f1324 | 943 | REAL_VALUE_TYPE x ATTRIBUTE_UNUSED; |
7d4d4d22 RS |
944 | { |
945 | return 0; | |
946 | } | |
947 | ||
6d716ca8 | 948 | /* Let's assume other float formats don't have minus zero. |
c05a9b68 | 949 | (This can be overridden by redefining REAL_VALUE_NEGATIVE.) */ |
6d716ca8 | 950 | |
7762d54e | 951 | int |
c05a9b68 | 952 | target_negative (x) |
6d716ca8 RS |
953 | REAL_VALUE_TYPE x; |
954 | { | |
c05a9b68 | 955 | return x < 0; |
6d716ca8 RS |
956 | } |
957 | #endif /* Target not IEEE */ | |
39647dcb RK |
958 | |
959 | /* Try to change R into its exact multiplicative inverse in machine mode | |
960 | MODE. Return nonzero function value if successful. */ | |
94aca342 ZW |
961 | struct exact_real_inverse_args |
962 | { | |
963 | REAL_VALUE_TYPE *r; | |
964 | enum machine_mode mode; | |
965 | int success; | |
966 | }; | |
39647dcb | 967 | |
94aca342 ZW |
968 | static void |
969 | exact_real_inverse_1 (p) | |
970 | PTR p; | |
39647dcb | 971 | { |
94aca342 ZW |
972 | struct exact_real_inverse_args *args = |
973 | (struct exact_real_inverse_args *) p; | |
974 | ||
975 | enum machine_mode mode = args->mode; | |
976 | REAL_VALUE_TYPE *r = args->r; | |
977 | ||
39647dcb | 978 | union |
94aca342 ZW |
979 | { |
980 | double d; | |
981 | unsigned short i[4]; | |
982 | } | |
983 | x, t, y; | |
7bdb32b9 | 984 | #ifdef CHECK_FLOAT_VALUE |
39647dcb | 985 | int i; |
7bdb32b9 | 986 | #endif |
39647dcb | 987 | |
39647dcb | 988 | /* Set array index to the less significant bits in the unions, depending |
94aca342 ZW |
989 | on the endian-ness of the host doubles. */ |
990 | #if HOST_FLOAT_FORMAT == VAX_FLOAT_FORMAT \ | |
991 | || HOST_FLOAT_FORMAT == IBM_FLOAT_FORMAT | |
992 | # define K 2 | |
39647dcb | 993 | #else |
94aca342 | 994 | # define K (2 * HOST_FLOAT_WORDS_BIG_ENDIAN) |
39647dcb RK |
995 | #endif |
996 | ||
39647dcb RK |
997 | /* Domain check the argument. */ |
998 | x.d = *r; | |
999 | if (x.d == 0.0) | |
1000 | goto fail; | |
1001 | ||
1002 | #ifdef REAL_INFINITY | |
1003 | if (REAL_VALUE_ISINF (x.d) || REAL_VALUE_ISNAN (x.d)) | |
1004 | goto fail; | |
1005 | #endif | |
1006 | ||
1007 | /* Compute the reciprocal and check for numerical exactness. | |
1008 | It is unnecessary to check all the significand bits to determine | |
1009 | whether X is a power of 2. If X is not, then it is impossible for | |
1010 | the bottom half significand of both X and 1/X to be all zero bits. | |
1011 | Hence we ignore the data structure of the top half and examine only | |
1012 | the low order bits of the two significands. */ | |
1013 | t.d = 1.0 / x.d; | |
1014 | if (x.i[K] != 0 || x.i[K + 1] != 0 || t.i[K] != 0 || t.i[K + 1] != 0) | |
1015 | goto fail; | |
1016 | ||
1017 | /* Truncate to the required mode and range-check the result. */ | |
1018 | y.d = REAL_VALUE_TRUNCATE (mode, t.d); | |
1019 | #ifdef CHECK_FLOAT_VALUE | |
1020 | i = 0; | |
1021 | if (CHECK_FLOAT_VALUE (mode, y.d, i)) | |
1022 | goto fail; | |
1023 | #endif | |
1024 | ||
1025 | /* Fail if truncation changed the value. */ | |
1026 | if (y.d != t.d || y.d == 0.0) | |
1027 | goto fail; | |
1028 | ||
1029 | #ifdef REAL_INFINITY | |
1030 | if (REAL_VALUE_ISINF (y.d) || REAL_VALUE_ISNAN (y.d)) | |
1031 | goto fail; | |
1032 | #endif | |
1033 | ||
1034 | /* Output the reciprocal and return success flag. */ | |
39647dcb | 1035 | *r = y.d; |
94aca342 ZW |
1036 | args->success = 1; |
1037 | return; | |
1038 | ||
1039 | fail: | |
1040 | args->success = 0; | |
1041 | return; | |
1042 | ||
1043 | #undef K | |
1044 | } | |
1045 | ||
1046 | ||
1047 | int | |
1048 | exact_real_inverse (mode, r) | |
1049 | enum machine_mode mode; | |
1050 | REAL_VALUE_TYPE *r; | |
1051 | { | |
1052 | struct exact_real_inverse_args args; | |
1053 | ||
1054 | /* Disable if insufficient information on the data structure. */ | |
1055 | #if HOST_FLOAT_FORMAT == UNKNOWN_FLOAT_FORMAT | |
1056 | return 0; | |
1057 | #endif | |
1058 | ||
1059 | /* Usually disable if bounds checks are not reliable. */ | |
1060 | if ((HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT) && !flag_pretend_float) | |
1061 | return 0; | |
1062 | ||
1063 | args.mode = mode; | |
1064 | args.r = r; | |
1065 | ||
1066 | if (do_float_handler (exact_real_inverse_1, (PTR) &args)) | |
1067 | return args.success; | |
1068 | return 0; | |
39647dcb | 1069 | } |
6f4d7222 | 1070 | |
526aba28 | 1071 | /* Convert C99 hexadecimal floating point string constant S. Return |
6f4d7222 | 1072 | real value type in mode MODE. This function uses the host computer's |
d4b60170 | 1073 | floating point arithmetic when there is no REAL_ARITHMETIC. */ |
6f4d7222 UD |
1074 | |
1075 | REAL_VALUE_TYPE | |
1076 | real_hex_to_f (s, mode) | |
08c148a8 | 1077 | const char *s; |
6f4d7222 UD |
1078 | enum machine_mode mode; |
1079 | { | |
b6cc0a72 | 1080 | REAL_VALUE_TYPE ip; |
08c148a8 | 1081 | const char *p = s; |
b6cc0a72 KH |
1082 | unsigned HOST_WIDE_INT low, high; |
1083 | int shcount, nrmcount, k; | |
1084 | int sign, expsign, isfloat; | |
1085 | int lost = 0;/* Nonzero low order bits shifted out and discarded. */ | |
1086 | int frexpon = 0; /* Bits after the decimal point. */ | |
1087 | int expon = 0; /* Value of exponent. */ | |
1088 | int decpt = 0; /* How many decimal points. */ | |
1089 | int gotp = 0; /* How many P's. */ | |
1090 | char c; | |
1091 | ||
1092 | isfloat = 0; | |
1093 | expsign = 1; | |
1094 | ip = 0.0; | |
1095 | ||
1096 | while (*p == ' ' || *p == '\t') | |
1097 | ++p; | |
1098 | ||
1099 | /* Sign, if any, comes first. */ | |
1100 | sign = 1; | |
1101 | if (*p == '-') | |
1102 | { | |
1103 | sign = -1; | |
1104 | ++p; | |
1105 | } | |
1106 | ||
1107 | /* The string is supposed to start with 0x or 0X . */ | |
1108 | if (*p == '0') | |
1109 | { | |
1110 | ++p; | |
1111 | if (*p == 'x' || *p == 'X') | |
1112 | ++p; | |
1113 | else | |
1114 | abort (); | |
1115 | } | |
1116 | else | |
1117 | abort (); | |
1118 | ||
1119 | while (*p == '0') | |
1120 | ++p; | |
1121 | ||
1122 | high = 0; | |
1123 | low = 0; | |
1124 | shcount = 0; | |
1125 | while ((c = *p) != '\0') | |
1126 | { | |
1127 | if ((c >= '0' && c <= '9') || (c >= 'A' && c <= 'F') | |
1128 | || (c >= 'a' && c <= 'f')) | |
1129 | { | |
1130 | k = c & CHARMASK; | |
1131 | if (k >= 'a' && k <= 'f') | |
1132 | k = k - 'a' + 10; | |
1133 | else if (k >= 'A') | |
1134 | k = k - 'A' + 10; | |
1135 | else | |
1136 | k = k - '0'; | |
1137 | ||
1138 | if ((high & 0xf0000000) == 0) | |
1139 | { | |
1140 | high = (high << 4) + ((low >> 28) & 15); | |
1141 | low = (low << 4) + k; | |
1142 | shcount += 4; | |
1143 | if (decpt) | |
1144 | frexpon += 4; | |
1145 | } | |
1146 | else | |
1147 | { | |
1148 | /* Record nonzero lost bits. */ | |
1149 | lost |= k; | |
1150 | if (! decpt) | |
1151 | frexpon -= 4; | |
1152 | } | |
1153 | ++p; | |
1154 | } | |
1155 | else if (c == '.') | |
1156 | { | |
1157 | ++decpt; | |
1158 | ++p; | |
1159 | } | |
1160 | ||
1161 | else if (c == 'p' || c == 'P') | |
1162 | { | |
1163 | ++gotp; | |
1164 | ++p; | |
1165 | /* Sign of exponent. */ | |
1166 | if (*p == '-') | |
1167 | { | |
1168 | expsign = -1; | |
1169 | ++p; | |
1170 | } | |
1171 | ||
1172 | /* Value of exponent. | |
1173 | The exponent field is a decimal integer. */ | |
1174 | while (ISDIGIT (*p)) | |
1175 | { | |
1176 | k = (*p++ & CHARMASK) - '0'; | |
1177 | expon = 10 * expon + k; | |
1178 | } | |
1179 | ||
1180 | expon *= expsign; | |
1181 | /* F suffix is ambiguous in the significand part | |
1182 | so it must appear after the decimal exponent field. */ | |
1183 | if (*p == 'f' || *p == 'F') | |
1184 | { | |
1185 | isfloat = 1; | |
1186 | ++p; | |
1187 | break; | |
1188 | } | |
1189 | } | |
1190 | ||
1191 | else if (c == 'l' || c == 'L') | |
1192 | { | |
1193 | ++p; | |
1194 | break; | |
1195 | } | |
1196 | else | |
1197 | break; | |
1198 | } | |
1199 | ||
1200 | /* Abort if last character read was not legitimate. */ | |
1201 | c = *p; | |
1202 | if ((c != '\0' && c != ' ' && c != '\n' && c != '\r') || (decpt > 1)) | |
1203 | abort (); | |
1204 | ||
1205 | /* There must be either one decimal point or one p. */ | |
1206 | if (decpt == 0 && gotp == 0) | |
1207 | abort (); | |
1208 | ||
1209 | shcount -= 4; | |
1210 | if (high == 0 && low == 0) | |
1211 | return dconst0; | |
1212 | ||
1213 | /* Normalize. */ | |
1214 | nrmcount = 0; | |
1215 | if (high == 0) | |
1216 | { | |
1217 | high = low; | |
1218 | low = 0; | |
1219 | nrmcount += 32; | |
1220 | } | |
1221 | ||
1222 | /* Leave a high guard bit for carry-out. */ | |
1223 | if ((high & 0x80000000) != 0) | |
1224 | { | |
1225 | lost |= low & 1; | |
1226 | low = (low >> 1) | (high << 31); | |
1227 | high = high >> 1; | |
1228 | nrmcount -= 1; | |
1229 | } | |
1230 | ||
1231 | if ((high & 0xffff8000) == 0) | |
1232 | { | |
1233 | high = (high << 16) + ((low >> 16) & 0xffff); | |
1234 | low = low << 16; | |
1235 | nrmcount += 16; | |
1236 | } | |
1237 | ||
1238 | while ((high & 0xc0000000) == 0) | |
1239 | { | |
1240 | high = (high << 1) + ((low >> 31) & 1); | |
1241 | low = low << 1; | |
1242 | nrmcount += 1; | |
1243 | } | |
1244 | ||
1245 | if (isfloat || GET_MODE_SIZE (mode) == UNITS_PER_WORD) | |
1246 | { | |
1247 | /* Keep 24 bits precision, bits 0x7fffff80. | |
1248 | Rounding bit is 0x40. */ | |
1249 | lost = lost | low | (high & 0x3f); | |
1250 | low = 0; | |
1251 | if (high & 0x40) | |
1252 | { | |
1253 | if ((high & 0x80) || lost) | |
1254 | high += 0x40; | |
1255 | } | |
1256 | high &= 0xffffff80; | |
1257 | } | |
1258 | else | |
1259 | { | |
1260 | /* We need real.c to do long double formats, so here default | |
1261 | to double precision. */ | |
6f4d7222 | 1262 | #if HOST_FLOAT_FORMAT == IEEE_FLOAT_FORMAT |
b6cc0a72 KH |
1263 | /* IEEE double. |
1264 | Keep 53 bits precision, bits 0x7fffffff fffffc00. | |
1265 | Rounding bit is low word 0x200. */ | |
1266 | lost = lost | (low & 0x1ff); | |
1267 | if (low & 0x200) | |
1268 | { | |
1269 | if ((low & 0x400) || lost) | |
1270 | { | |
1271 | low = (low + 0x200) & 0xfffffc00; | |
1272 | if (low == 0) | |
1273 | high += 1; | |
1274 | } | |
1275 | } | |
1276 | low &= 0xfffffc00; | |
6f4d7222 | 1277 | #else |
b6cc0a72 KH |
1278 | /* Assume it's a VAX with 56-bit significand, |
1279 | bits 0x7fffffff ffffff80. */ | |
1280 | lost = lost | (low & 0x7f); | |
1281 | if (low & 0x40) | |
1282 | { | |
1283 | if ((low & 0x80) || lost) | |
1284 | { | |
1285 | low = (low + 0x40) & 0xffffff80; | |
1286 | if (low == 0) | |
1287 | high += 1; | |
1288 | } | |
1289 | } | |
1290 | low &= 0xffffff80; | |
6f4d7222 | 1291 | #endif |
b6cc0a72 | 1292 | } |
d4b60170 | 1293 | |
b6cc0a72 KH |
1294 | ip = (double) high; |
1295 | ip = REAL_VALUE_LDEXP (ip, 32) + (double) low; | |
1296 | /* Apply shifts and exponent value as power of 2. */ | |
1297 | ip = REAL_VALUE_LDEXP (ip, expon - (nrmcount + frexpon)); | |
6f4d7222 | 1298 | |
b6cc0a72 KH |
1299 | if (sign < 0) |
1300 | ip = -ip; | |
1301 | return ip; | |
6f4d7222 UD |
1302 | } |
1303 | ||
5008b8ae | 1304 | #endif /* no REAL_ARITHMETIC */ |
6d716ca8 | 1305 | \f |
1baa375f RK |
1306 | /* Given T, an expression, return the negation of T. Allow for T to be |
1307 | null, in which case return null. */ | |
6d716ca8 | 1308 | |
1baa375f RK |
1309 | static tree |
1310 | negate_expr (t) | |
1311 | tree t; | |
1312 | { | |
1313 | tree type; | |
1314 | tree tem; | |
1315 | ||
1316 | if (t == 0) | |
1317 | return 0; | |
1318 | ||
1319 | type = TREE_TYPE (t); | |
1320 | STRIP_SIGN_NOPS (t); | |
1321 | ||
1322 | switch (TREE_CODE (t)) | |
1323 | { | |
1324 | case INTEGER_CST: | |
1325 | case REAL_CST: | |
1326 | if (! TREE_UNSIGNED (type) | |
1327 | && 0 != (tem = fold (build1 (NEGATE_EXPR, type, t))) | |
1328 | && ! TREE_OVERFLOW (tem)) | |
1329 | return tem; | |
1330 | break; | |
1331 | ||
1332 | case NEGATE_EXPR: | |
1333 | return convert (type, TREE_OPERAND (t, 0)); | |
1334 | ||
1335 | case MINUS_EXPR: | |
1336 | /* - (A - B) -> B - A */ | |
de6c5979 | 1337 | if (! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations) |
1baa375f RK |
1338 | return convert (type, |
1339 | fold (build (MINUS_EXPR, TREE_TYPE (t), | |
1340 | TREE_OPERAND (t, 1), | |
1341 | TREE_OPERAND (t, 0)))); | |
1342 | break; | |
1343 | ||
1344 | default: | |
1345 | break; | |
1346 | } | |
1347 | ||
1348 | return convert (type, build1 (NEGATE_EXPR, TREE_TYPE (t), t)); | |
1349 | } | |
1350 | \f | |
1351 | /* Split a tree IN into a constant, literal and variable parts that could be | |
1352 | combined with CODE to make IN. "constant" means an expression with | |
1353 | TREE_CONSTANT but that isn't an actual constant. CODE must be a | |
1354 | commutative arithmetic operation. Store the constant part into *CONP, | |
1355 | the literal in &LITP and return the variable part. If a part isn't | |
1356 | present, set it to null. If the tree does not decompose in this way, | |
1357 | return the entire tree as the variable part and the other parts as null. | |
1358 | ||
1359 | If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that | |
1360 | case, we negate an operand that was subtracted. If NEGATE_P is true, we | |
1361 | are negating all of IN. | |
1362 | ||
1363 | If IN is itself a literal or constant, return it as appropriate. | |
1364 | ||
1365 | Note that we do not guarantee that any of the three values will be the | |
1366 | same type as IN, but they will have the same signedness and mode. */ | |
1367 | ||
1368 | static tree | |
1369 | split_tree (in, code, conp, litp, negate_p) | |
6d716ca8 RS |
1370 | tree in; |
1371 | enum tree_code code; | |
1baa375f RK |
1372 | tree *conp, *litp; |
1373 | int negate_p; | |
6d716ca8 | 1374 | { |
1baa375f RK |
1375 | tree var = 0; |
1376 | ||
6d716ca8 | 1377 | *conp = 0; |
1baa375f RK |
1378 | *litp = 0; |
1379 | ||
30f7a378 | 1380 | /* Strip any conversions that don't change the machine mode or signedness. */ |
1baa375f RK |
1381 | STRIP_SIGN_NOPS (in); |
1382 | ||
1383 | if (TREE_CODE (in) == INTEGER_CST || TREE_CODE (in) == REAL_CST) | |
1384 | *litp = in; | |
1baa375f RK |
1385 | else if (TREE_CODE (in) == code |
1386 | || (! FLOAT_TYPE_P (TREE_TYPE (in)) | |
1387 | /* We can associate addition and subtraction together (even | |
1388 | though the C standard doesn't say so) for integers because | |
1389 | the value is not affected. For reals, the value might be | |
1390 | affected, so we can't. */ | |
1391 | && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR) | |
1392 | || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR)))) | |
1393 | { | |
1394 | tree op0 = TREE_OPERAND (in, 0); | |
1395 | tree op1 = TREE_OPERAND (in, 1); | |
1396 | int neg1_p = TREE_CODE (in) == MINUS_EXPR; | |
1397 | int neg_litp_p = 0, neg_conp_p = 0, neg_var_p = 0; | |
1398 | ||
1399 | /* First see if either of the operands is a literal, then a constant. */ | |
1400 | if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST) | |
1401 | *litp = op0, op0 = 0; | |
1402 | else if (TREE_CODE (op1) == INTEGER_CST || TREE_CODE (op1) == REAL_CST) | |
1403 | *litp = op1, neg_litp_p = neg1_p, op1 = 0; | |
1404 | ||
1405 | if (op0 != 0 && TREE_CONSTANT (op0)) | |
1406 | *conp = op0, op0 = 0; | |
1407 | else if (op1 != 0 && TREE_CONSTANT (op1)) | |
1408 | *conp = op1, neg_conp_p = neg1_p, op1 = 0; | |
1409 | ||
1410 | /* If we haven't dealt with either operand, this is not a case we can | |
30f7a378 | 1411 | decompose. Otherwise, VAR is either of the ones remaining, if any. */ |
1baa375f RK |
1412 | if (op0 != 0 && op1 != 0) |
1413 | var = in; | |
1414 | else if (op0 != 0) | |
1415 | var = op0; | |
1416 | else | |
1417 | var = op1, neg_var_p = neg1_p; | |
6d716ca8 | 1418 | |
1baa375f RK |
1419 | /* Now do any needed negations. */ |
1420 | if (neg_litp_p) *litp = negate_expr (*litp); | |
1421 | if (neg_conp_p) *conp = negate_expr (*conp); | |
1422 | if (neg_var_p) var = negate_expr (var); | |
1423 | } | |
1796dff4 RH |
1424 | else if (TREE_CONSTANT (in)) |
1425 | *conp = in; | |
1baa375f RK |
1426 | else |
1427 | var = in; | |
1428 | ||
1429 | if (negate_p) | |
6d716ca8 | 1430 | { |
1baa375f RK |
1431 | var = negate_expr (var); |
1432 | *conp = negate_expr (*conp); | |
1433 | *litp = negate_expr (*litp); | |
6d716ca8 | 1434 | } |
1baa375f RK |
1435 | |
1436 | return var; | |
1437 | } | |
1438 | ||
1439 | /* Re-associate trees split by the above function. T1 and T2 are either | |
1440 | expressions to associate or null. Return the new expression, if any. If | |
1441 | we build an operation, do it in TYPE and with CODE, except if CODE is a | |
1442 | MINUS_EXPR, in which case we use PLUS_EXPR since split_tree will already | |
1443 | have taken care of the negations. */ | |
1444 | ||
1445 | static tree | |
1446 | associate_trees (t1, t2, code, type) | |
1447 | tree t1, t2; | |
1448 | enum tree_code code; | |
1449 | tree type; | |
1450 | { | |
1baa375f RK |
1451 | if (t1 == 0) |
1452 | return t2; | |
1453 | else if (t2 == 0) | |
1454 | return t1; | |
1455 | ||
1456 | if (code == MINUS_EXPR) | |
1457 | code = PLUS_EXPR; | |
1458 | ||
1459 | /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't | |
1460 | try to fold this since we will have infinite recursion. But do | |
1461 | deal with any NEGATE_EXPRs. */ | |
1462 | if (TREE_CODE (t1) == code || TREE_CODE (t2) == code | |
1463 | || TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR) | |
1464 | { | |
1465 | if (TREE_CODE (t1) == NEGATE_EXPR) | |
1466 | return build (MINUS_EXPR, type, convert (type, t2), | |
1467 | convert (type, TREE_OPERAND (t1, 0))); | |
1468 | else if (TREE_CODE (t2) == NEGATE_EXPR) | |
1469 | return build (MINUS_EXPR, type, convert (type, t1), | |
1470 | convert (type, TREE_OPERAND (t2, 0))); | |
1471 | else | |
1472 | return build (code, type, convert (type, t1), convert (type, t2)); | |
1473 | } | |
1474 | ||
1475 | return fold (build (code, type, convert (type, t1), convert (type, t2))); | |
6d716ca8 RS |
1476 | } |
1477 | \f | |
e9a25f70 | 1478 | /* Combine two integer constants ARG1 and ARG2 under operation CODE |
6d716ca8 | 1479 | to produce a new constant. |
91d33e36 | 1480 | |
e9a25f70 JL |
1481 | If NOTRUNC is nonzero, do not truncate the result to fit the data type. |
1482 | If FORSIZE is nonzero, compute overflow for unsigned types. */ | |
6d716ca8 | 1483 | |
6d716ca8 | 1484 | static tree |
e9a25f70 | 1485 | int_const_binop (code, arg1, arg2, notrunc, forsize) |
6d716ca8 RS |
1486 | enum tree_code code; |
1487 | register tree arg1, arg2; | |
e9a25f70 | 1488 | int notrunc, forsize; |
6d716ca8 | 1489 | { |
05bccae2 RK |
1490 | unsigned HOST_WIDE_INT int1l, int2l; |
1491 | HOST_WIDE_INT int1h, int2h; | |
1492 | unsigned HOST_WIDE_INT low; | |
1493 | HOST_WIDE_INT hi; | |
1494 | unsigned HOST_WIDE_INT garbagel; | |
1495 | HOST_WIDE_INT garbageh; | |
e9a25f70 JL |
1496 | register tree t; |
1497 | int uns = TREE_UNSIGNED (TREE_TYPE (arg1)); | |
1498 | int overflow = 0; | |
1499 | int no_overflow = 0; | |
3dedc65a | 1500 | |
e9a25f70 JL |
1501 | int1l = TREE_INT_CST_LOW (arg1); |
1502 | int1h = TREE_INT_CST_HIGH (arg1); | |
1503 | int2l = TREE_INT_CST_LOW (arg2); | |
1504 | int2h = TREE_INT_CST_HIGH (arg2); | |
1505 | ||
1506 | switch (code) | |
6d716ca8 | 1507 | { |
e9a25f70 JL |
1508 | case BIT_IOR_EXPR: |
1509 | low = int1l | int2l, hi = int1h | int2h; | |
1510 | break; | |
6d716ca8 | 1511 | |
e9a25f70 JL |
1512 | case BIT_XOR_EXPR: |
1513 | low = int1l ^ int2l, hi = int1h ^ int2h; | |
1514 | break; | |
6d716ca8 | 1515 | |
e9a25f70 JL |
1516 | case BIT_AND_EXPR: |
1517 | low = int1l & int2l, hi = int1h & int2h; | |
1518 | break; | |
6d716ca8 | 1519 | |
e9a25f70 JL |
1520 | case BIT_ANDTC_EXPR: |
1521 | low = int1l & ~int2l, hi = int1h & ~int2h; | |
1522 | break; | |
6d716ca8 | 1523 | |
e9a25f70 | 1524 | case RSHIFT_EXPR: |
b6cc0a72 | 1525 | int2l = -int2l; |
e9a25f70 JL |
1526 | case LSHIFT_EXPR: |
1527 | /* It's unclear from the C standard whether shifts can overflow. | |
1528 | The following code ignores overflow; perhaps a C standard | |
1529 | interpretation ruling is needed. */ | |
770ae6cc RK |
1530 | lshift_double (int1l, int1h, int2l, TYPE_PRECISION (TREE_TYPE (arg1)), |
1531 | &low, &hi, !uns); | |
e9a25f70 JL |
1532 | no_overflow = 1; |
1533 | break; | |
6d716ca8 | 1534 | |
e9a25f70 JL |
1535 | case RROTATE_EXPR: |
1536 | int2l = - int2l; | |
1537 | case LROTATE_EXPR: | |
770ae6cc | 1538 | lrotate_double (int1l, int1h, int2l, TYPE_PRECISION (TREE_TYPE (arg1)), |
e9a25f70 JL |
1539 | &low, &hi); |
1540 | break; | |
6d716ca8 | 1541 | |
e9a25f70 JL |
1542 | case PLUS_EXPR: |
1543 | overflow = add_double (int1l, int1h, int2l, int2h, &low, &hi); | |
1544 | break; | |
6d716ca8 | 1545 | |
e9a25f70 JL |
1546 | case MINUS_EXPR: |
1547 | neg_double (int2l, int2h, &low, &hi); | |
1548 | add_double (int1l, int1h, low, hi, &low, &hi); | |
d4b60170 | 1549 | overflow = OVERFLOW_SUM_SIGN (hi, int2h, int1h); |
e9a25f70 | 1550 | break; |
6d716ca8 | 1551 | |
e9a25f70 JL |
1552 | case MULT_EXPR: |
1553 | overflow = mul_double (int1l, int1h, int2l, int2h, &low, &hi); | |
1554 | break; | |
6d716ca8 | 1555 | |
e9a25f70 JL |
1556 | case TRUNC_DIV_EXPR: |
1557 | case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR: | |
1558 | case EXACT_DIV_EXPR: | |
1559 | /* This is a shortcut for a common special case. */ | |
05bccae2 | 1560 | if (int2h == 0 && (HOST_WIDE_INT) int2l > 0 |
e9a25f70 JL |
1561 | && ! TREE_CONSTANT_OVERFLOW (arg1) |
1562 | && ! TREE_CONSTANT_OVERFLOW (arg2) | |
05bccae2 | 1563 | && int1h == 0 && (HOST_WIDE_INT) int1l >= 0) |
e9a25f70 JL |
1564 | { |
1565 | if (code == CEIL_DIV_EXPR) | |
1566 | int1l += int2l - 1; | |
05bccae2 | 1567 | |
e9a25f70 | 1568 | low = int1l / int2l, hi = 0; |
6d716ca8 | 1569 | break; |
e9a25f70 | 1570 | } |
6d716ca8 | 1571 | |
30f7a378 | 1572 | /* ... fall through ... */ |
6d716ca8 | 1573 | |
b6cc0a72 | 1574 | case ROUND_DIV_EXPR: |
e9a25f70 JL |
1575 | if (int2h == 0 && int2l == 1) |
1576 | { | |
1577 | low = int1l, hi = int1h; | |
6d716ca8 | 1578 | break; |
e9a25f70 JL |
1579 | } |
1580 | if (int1l == int2l && int1h == int2h | |
1581 | && ! (int1l == 0 && int1h == 0)) | |
1582 | { | |
1583 | low = 1, hi = 0; | |
63e7fe9b | 1584 | break; |
e9a25f70 JL |
1585 | } |
1586 | overflow = div_and_round_double (code, uns, | |
1587 | int1l, int1h, int2l, int2h, | |
1588 | &low, &hi, &garbagel, &garbageh); | |
1589 | break; | |
63e7fe9b | 1590 | |
e9a25f70 JL |
1591 | case TRUNC_MOD_EXPR: |
1592 | case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR: | |
1593 | /* This is a shortcut for a common special case. */ | |
05bccae2 | 1594 | if (int2h == 0 && (HOST_WIDE_INT) int2l > 0 |
e9a25f70 JL |
1595 | && ! TREE_CONSTANT_OVERFLOW (arg1) |
1596 | && ! TREE_CONSTANT_OVERFLOW (arg2) | |
05bccae2 | 1597 | && int1h == 0 && (HOST_WIDE_INT) int1l >= 0) |
e9a25f70 JL |
1598 | { |
1599 | if (code == CEIL_MOD_EXPR) | |
1600 | int1l += int2l - 1; | |
1601 | low = int1l % int2l, hi = 0; | |
63e7fe9b | 1602 | break; |
e9a25f70 | 1603 | } |
63e7fe9b | 1604 | |
30f7a378 | 1605 | /* ... fall through ... */ |
e9a25f70 | 1606 | |
b6cc0a72 | 1607 | case ROUND_MOD_EXPR: |
e9a25f70 JL |
1608 | overflow = div_and_round_double (code, uns, |
1609 | int1l, int1h, int2l, int2h, | |
1610 | &garbagel, &garbageh, &low, &hi); | |
1611 | break; | |
1612 | ||
1613 | case MIN_EXPR: | |
1614 | case MAX_EXPR: | |
1615 | if (uns) | |
d4b60170 RK |
1616 | low = (((unsigned HOST_WIDE_INT) int1h |
1617 | < (unsigned HOST_WIDE_INT) int2h) | |
1618 | || (((unsigned HOST_WIDE_INT) int1h | |
1619 | == (unsigned HOST_WIDE_INT) int2h) | |
05bccae2 | 1620 | && int1l < int2l)); |
380ff34a | 1621 | else |
05bccae2 RK |
1622 | low = (int1h < int2h |
1623 | || (int1h == int2h && int1l < int2l)); | |
d4b60170 | 1624 | |
e9a25f70 JL |
1625 | if (low == (code == MIN_EXPR)) |
1626 | low = int1l, hi = int1h; | |
1627 | else | |
1628 | low = int2l, hi = int2h; | |
1629 | break; | |
3dedc65a | 1630 | |
e9a25f70 JL |
1631 | default: |
1632 | abort (); | |
3dedc65a | 1633 | } |
e9a25f70 | 1634 | |
44475138 RK |
1635 | if (forsize && hi == 0 && low < 10000 |
1636 | && overflow == 0 && ! TREE_OVERFLOW (arg1) && ! TREE_OVERFLOW (arg2)) | |
fed3cef0 | 1637 | return size_int_type_wide (low, TREE_TYPE (arg1)); |
e9a25f70 JL |
1638 | else |
1639 | { | |
1640 | t = build_int_2 (low, hi); | |
1641 | TREE_TYPE (t) = TREE_TYPE (arg1); | |
1642 | } | |
1643 | ||
1644 | TREE_OVERFLOW (t) | |
1645 | = ((notrunc ? (!uns || forsize) && overflow | |
1646 | : force_fit_type (t, (!uns || forsize) && overflow) && ! no_overflow) | |
1647 | | TREE_OVERFLOW (arg1) | |
1648 | | TREE_OVERFLOW (arg2)); | |
d4b60170 | 1649 | |
e9a25f70 JL |
1650 | /* If we're doing a size calculation, unsigned arithmetic does overflow. |
1651 | So check if force_fit_type truncated the value. */ | |
1652 | if (forsize | |
1653 | && ! TREE_OVERFLOW (t) | |
1654 | && (TREE_INT_CST_HIGH (t) != hi | |
1655 | || TREE_INT_CST_LOW (t) != low)) | |
1656 | TREE_OVERFLOW (t) = 1; | |
d4b60170 | 1657 | |
e9a25f70 JL |
1658 | TREE_CONSTANT_OVERFLOW (t) = (TREE_OVERFLOW (t) |
1659 | | TREE_CONSTANT_OVERFLOW (arg1) | |
1660 | | TREE_CONSTANT_OVERFLOW (arg2)); | |
1661 | return t; | |
1662 | } | |
1663 | ||
d4b60170 | 1664 | /* Define input and output argument for const_binop_1. */ |
a4d3481d KG |
1665 | struct cb_args |
1666 | { | |
b6cc0a72 KH |
1667 | enum tree_code code; /* Input: tree code for operation. */ |
1668 | tree type; /* Input: tree type for operation. */ | |
1669 | REAL_VALUE_TYPE d1, d2; /* Input: floating point operands. */ | |
1670 | tree t; /* Output: constant for result. */ | |
a4d3481d KG |
1671 | }; |
1672 | ||
d4b60170 RK |
1673 | /* Do the real arithmetic for const_binop while protected by a |
1674 | float overflow handler. */ | |
1675 | ||
a4d3481d KG |
1676 | static void |
1677 | const_binop_1 (data) | |
b6cc0a72 | 1678 | PTR data; |
a4d3481d | 1679 | { |
d4b60170 | 1680 | struct cb_args *args = (struct cb_args *) data; |
a4d3481d KG |
1681 | REAL_VALUE_TYPE value; |
1682 | ||
1683 | #ifdef REAL_ARITHMETIC | |
1684 | REAL_ARITHMETIC (value, args->code, args->d1, args->d2); | |
1685 | #else | |
1686 | switch (args->code) | |
1687 | { | |
1688 | case PLUS_EXPR: | |
1689 | value = args->d1 + args->d2; | |
1690 | break; | |
b6cc0a72 | 1691 | |
a4d3481d KG |
1692 | case MINUS_EXPR: |
1693 | value = args->d1 - args->d2; | |
1694 | break; | |
b6cc0a72 | 1695 | |
a4d3481d KG |
1696 | case MULT_EXPR: |
1697 | value = args->d1 * args->d2; | |
1698 | break; | |
b6cc0a72 | 1699 | |
a4d3481d KG |
1700 | case RDIV_EXPR: |
1701 | #ifndef REAL_INFINITY | |
1702 | if (args->d2 == 0) | |
1703 | abort (); | |
1704 | #endif | |
b6cc0a72 | 1705 | |
a4d3481d KG |
1706 | value = args->d1 / args->d2; |
1707 | break; | |
b6cc0a72 | 1708 | |
a4d3481d KG |
1709 | case MIN_EXPR: |
1710 | value = MIN (args->d1, args->d2); | |
1711 | break; | |
b6cc0a72 | 1712 | |
a4d3481d KG |
1713 | case MAX_EXPR: |
1714 | value = MAX (args->d1, args->d2); | |
1715 | break; | |
b6cc0a72 | 1716 | |
a4d3481d KG |
1717 | default: |
1718 | abort (); | |
1719 | } | |
1720 | #endif /* no REAL_ARITHMETIC */ | |
d4b60170 RK |
1721 | |
1722 | args->t | |
1723 | = build_real (args->type, | |
1724 | real_value_truncate (TYPE_MODE (args->type), value)); | |
a4d3481d KG |
1725 | } |
1726 | ||
d4b60170 RK |
1727 | /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new |
1728 | constant. We assume ARG1 and ARG2 have the same data type, or at least | |
1729 | are the same kind of constant and the same machine mode. | |
e9a25f70 JL |
1730 | |
1731 | If NOTRUNC is nonzero, do not truncate the result to fit the data type. */ | |
1732 | ||
1733 | static tree | |
1734 | const_binop (code, arg1, arg2, notrunc) | |
1735 | enum tree_code code; | |
1736 | register tree arg1, arg2; | |
1737 | int notrunc; | |
1738 | { | |
b6cc0a72 KH |
1739 | STRIP_NOPS (arg1); |
1740 | STRIP_NOPS (arg2); | |
e9a25f70 JL |
1741 | |
1742 | if (TREE_CODE (arg1) == INTEGER_CST) | |
1743 | return int_const_binop (code, arg1, arg2, notrunc, 0); | |
1744 | ||
6d716ca8 RS |
1745 | #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) |
1746 | if (TREE_CODE (arg1) == REAL_CST) | |
1747 | { | |
79c844cd RK |
1748 | REAL_VALUE_TYPE d1; |
1749 | REAL_VALUE_TYPE d2; | |
649ff3b4 | 1750 | int overflow = 0; |
7c7b029d | 1751 | tree t; |
a4d3481d | 1752 | struct cb_args args; |
6d716ca8 | 1753 | |
79c844cd RK |
1754 | d1 = TREE_REAL_CST (arg1); |
1755 | d2 = TREE_REAL_CST (arg2); | |
5f610074 RK |
1756 | |
1757 | /* If either operand is a NaN, just return it. Otherwise, set up | |
1758 | for floating-point trap; we return an overflow. */ | |
1759 | if (REAL_VALUE_ISNAN (d1)) | |
1760 | return arg1; | |
1761 | else if (REAL_VALUE_ISNAN (d2)) | |
1762 | return arg2; | |
a4d3481d KG |
1763 | |
1764 | /* Setup input for const_binop_1() */ | |
d4b60170 | 1765 | args.type = TREE_TYPE (arg1); |
a4d3481d KG |
1766 | args.d1 = d1; |
1767 | args.d2 = d2; | |
1768 | args.code = code; | |
b6cc0a72 | 1769 | |
a4d3481d | 1770 | if (do_float_handler (const_binop_1, (PTR) &args)) |
30f7a378 | 1771 | /* Receive output from const_binop_1. */ |
d4b60170 | 1772 | t = args.t; |
a4d3481d | 1773 | else |
6d716ca8 | 1774 | { |
30f7a378 | 1775 | /* We got an exception from const_binop_1. */ |
a4d3481d KG |
1776 | t = copy_node (arg1); |
1777 | overflow = 1; | |
6d716ca8 | 1778 | } |
649ff3b4 RK |
1779 | |
1780 | TREE_OVERFLOW (t) | |
1781 | = (force_fit_type (t, overflow) | |
1782 | | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2)); | |
1783 | TREE_CONSTANT_OVERFLOW (t) | |
1784 | = TREE_OVERFLOW (t) | |
1785 | | TREE_CONSTANT_OVERFLOW (arg1) | |
1786 | | TREE_CONSTANT_OVERFLOW (arg2); | |
7c7b029d | 1787 | return t; |
6d716ca8 RS |
1788 | } |
1789 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
1790 | if (TREE_CODE (arg1) == COMPLEX_CST) | |
1791 | { | |
214d5b84 | 1792 | register tree type = TREE_TYPE (arg1); |
6d716ca8 RS |
1793 | register tree r1 = TREE_REALPART (arg1); |
1794 | register tree i1 = TREE_IMAGPART (arg1); | |
1795 | register tree r2 = TREE_REALPART (arg2); | |
1796 | register tree i2 = TREE_IMAGPART (arg2); | |
1797 | register tree t; | |
1798 | ||
1799 | switch (code) | |
1800 | { | |
1801 | case PLUS_EXPR: | |
214d5b84 RK |
1802 | t = build_complex (type, |
1803 | const_binop (PLUS_EXPR, r1, r2, notrunc), | |
91d33e36 | 1804 | const_binop (PLUS_EXPR, i1, i2, notrunc)); |
6d716ca8 RS |
1805 | break; |
1806 | ||
1807 | case MINUS_EXPR: | |
214d5b84 RK |
1808 | t = build_complex (type, |
1809 | const_binop (MINUS_EXPR, r1, r2, notrunc), | |
91d33e36 | 1810 | const_binop (MINUS_EXPR, i1, i2, notrunc)); |
6d716ca8 RS |
1811 | break; |
1812 | ||
1813 | case MULT_EXPR: | |
214d5b84 RK |
1814 | t = build_complex (type, |
1815 | const_binop (MINUS_EXPR, | |
91d33e36 RS |
1816 | const_binop (MULT_EXPR, |
1817 | r1, r2, notrunc), | |
1818 | const_binop (MULT_EXPR, | |
1819 | i1, i2, notrunc), | |
1820 | notrunc), | |
6d716ca8 | 1821 | const_binop (PLUS_EXPR, |
91d33e36 RS |
1822 | const_binop (MULT_EXPR, |
1823 | r1, i2, notrunc), | |
1824 | const_binop (MULT_EXPR, | |
1825 | i1, r2, notrunc), | |
1826 | notrunc)); | |
6d716ca8 RS |
1827 | break; |
1828 | ||
1829 | case RDIV_EXPR: | |
1830 | { | |
1831 | register tree magsquared | |
1832 | = const_binop (PLUS_EXPR, | |
91d33e36 RS |
1833 | const_binop (MULT_EXPR, r2, r2, notrunc), |
1834 | const_binop (MULT_EXPR, i2, i2, notrunc), | |
1835 | notrunc); | |
58633be8 | 1836 | |
214d5b84 RK |
1837 | t = build_complex (type, |
1838 | const_binop | |
1839 | (INTEGRAL_TYPE_P (TREE_TYPE (r1)) | |
1840 | ? TRUNC_DIV_EXPR : RDIV_EXPR, | |
1841 | const_binop (PLUS_EXPR, | |
1842 | const_binop (MULT_EXPR, r1, r2, | |
1843 | notrunc), | |
1844 | const_binop (MULT_EXPR, i1, i2, | |
1845 | notrunc), | |
1846 | notrunc), | |
1847 | magsquared, notrunc), | |
1848 | const_binop | |
1849 | (INTEGRAL_TYPE_P (TREE_TYPE (r1)) | |
1850 | ? TRUNC_DIV_EXPR : RDIV_EXPR, | |
1851 | const_binop (MINUS_EXPR, | |
1852 | const_binop (MULT_EXPR, i1, r2, | |
1853 | notrunc), | |
1854 | const_binop (MULT_EXPR, r1, i2, | |
1855 | notrunc), | |
1856 | notrunc), | |
1857 | magsquared, notrunc)); | |
6d716ca8 RS |
1858 | } |
1859 | break; | |
1860 | ||
1861 | default: | |
1862 | abort (); | |
1863 | } | |
6d716ca8 RS |
1864 | return t; |
1865 | } | |
1866 | return 0; | |
1867 | } | |
1868 | \f | |
06ceef4e | 1869 | /* Return an INTEGER_CST with value whose low-order HOST_BITS_PER_WIDE_INT |
fed3cef0 | 1870 | bits are given by NUMBER and of the sizetype represented by KIND. */ |
d4b60170 | 1871 | |
fed3cef0 RK |
1872 | tree |
1873 | size_int_wide (number, kind) | |
1874 | HOST_WIDE_INT number; | |
1875 | enum size_type_kind kind; | |
1876 | { | |
1877 | return size_int_type_wide (number, sizetype_tab[(int) kind]); | |
1878 | } | |
1879 | ||
1880 | /* Likewise, but the desired type is specified explicitly. */ | |
6d716ca8 RS |
1881 | |
1882 | tree | |
fed3cef0 | 1883 | size_int_type_wide (number, type) |
06ceef4e | 1884 | HOST_WIDE_INT number; |
fed3cef0 | 1885 | tree type; |
6d716ca8 | 1886 | { |
d4b60170 | 1887 | /* Type-size nodes already made for small sizes. */ |
770ae6cc | 1888 | static tree size_table[2048 + 1]; |
d4b60170 | 1889 | static int init_p = 0; |
a3770a81 | 1890 | tree t; |
b6cc0a72 | 1891 | |
1f8f4a0b | 1892 | if (! init_p) |
6d716ca8 | 1893 | { |
d4b60170 RK |
1894 | ggc_add_tree_root ((tree *) size_table, |
1895 | sizeof size_table / sizeof (tree)); | |
1896 | init_p = 1; | |
1897 | } | |
1898 | ||
06ceef4e RK |
1899 | /* If this is a positive number that fits in the table we use to hold |
1900 | cached entries, see if it is already in the table and put it there | |
1901 | if not. */ | |
b6a1cbae | 1902 | if (number >= 0 && number < (int) ARRAY_SIZE (size_table)) |
d4b60170 | 1903 | { |
fed3cef0 RK |
1904 | if (size_table[number] != 0) |
1905 | for (t = size_table[number]; t != 0; t = TREE_CHAIN (t)) | |
1906 | if (TREE_TYPE (t) == type) | |
1907 | return t; | |
06ceef4e | 1908 | |
d4b60170 | 1909 | t = build_int_2 (number, 0); |
fed3cef0 RK |
1910 | TREE_TYPE (t) = type; |
1911 | TREE_CHAIN (t) = size_table[number]; | |
1912 | size_table[number] = t; | |
d4b60170 | 1913 | |
d4b60170 | 1914 | return t; |
6d716ca8 | 1915 | } |
a3770a81 | 1916 | |
fed3cef0 RK |
1917 | t = build_int_2 (number, number < 0 ? -1 : 0); |
1918 | TREE_TYPE (t) = type; | |
a3770a81 | 1919 | TREE_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (t) = force_fit_type (t, 0); |
6d716ca8 RS |
1920 | return t; |
1921 | } | |
1922 | ||
fed3cef0 RK |
1923 | /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE |
1924 | is a tree code. The type of the result is taken from the operands. | |
1925 | Both must be the same type integer type and it must be a size type. | |
6d716ca8 RS |
1926 | If the operands are constant, so is the result. */ |
1927 | ||
1928 | tree | |
1929 | size_binop (code, arg0, arg1) | |
1930 | enum tree_code code; | |
1931 | tree arg0, arg1; | |
1932 | { | |
fed3cef0 RK |
1933 | tree type = TREE_TYPE (arg0); |
1934 | ||
21318741 RK |
1935 | if (TREE_CODE (type) != INTEGER_TYPE || ! TYPE_IS_SIZETYPE (type) |
1936 | || type != TREE_TYPE (arg1)) | |
fed3cef0 RK |
1937 | abort (); |
1938 | ||
6d716ca8 RS |
1939 | /* Handle the special case of two integer constants faster. */ |
1940 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) | |
1941 | { | |
1942 | /* And some specific cases even faster than that. */ | |
9898deac | 1943 | if (code == PLUS_EXPR && integer_zerop (arg0)) |
6d716ca8 | 1944 | return arg1; |
9898deac RK |
1945 | else if ((code == MINUS_EXPR || code == PLUS_EXPR) |
1946 | && integer_zerop (arg1)) | |
6d716ca8 | 1947 | return arg0; |
9898deac | 1948 | else if (code == MULT_EXPR && integer_onep (arg0)) |
6d716ca8 | 1949 | return arg1; |
9898deac | 1950 | |
6d716ca8 | 1951 | /* Handle general case of two integer constants. */ |
e9a25f70 | 1952 | return int_const_binop (code, arg0, arg1, 0, 1); |
6d716ca8 RS |
1953 | } |
1954 | ||
1955 | if (arg0 == error_mark_node || arg1 == error_mark_node) | |
1956 | return error_mark_node; | |
1957 | ||
fed3cef0 | 1958 | return fold (build (code, type, arg0, arg1)); |
6d716ca8 | 1959 | } |
697073d9 | 1960 | |
fed3cef0 RK |
1961 | /* Given two values, either both of sizetype or both of bitsizetype, |
1962 | compute the difference between the two values. Return the value | |
1963 | in signed type corresponding to the type of the operands. */ | |
697073d9 JM |
1964 | |
1965 | tree | |
fed3cef0 | 1966 | size_diffop (arg0, arg1) |
697073d9 JM |
1967 | tree arg0, arg1; |
1968 | { | |
fed3cef0 RK |
1969 | tree type = TREE_TYPE (arg0); |
1970 | tree ctype; | |
697073d9 | 1971 | |
21318741 RK |
1972 | if (TREE_CODE (type) != INTEGER_TYPE || ! TYPE_IS_SIZETYPE (type) |
1973 | || type != TREE_TYPE (arg1)) | |
fed3cef0 | 1974 | abort (); |
697073d9 | 1975 | |
fed3cef0 RK |
1976 | /* If the type is already signed, just do the simple thing. */ |
1977 | if (! TREE_UNSIGNED (type)) | |
1978 | return size_binop (MINUS_EXPR, arg0, arg1); | |
1979 | ||
1980 | ctype = (type == bitsizetype || type == ubitsizetype | |
1981 | ? sbitsizetype : ssizetype); | |
1982 | ||
1983 | /* If either operand is not a constant, do the conversions to the signed | |
1984 | type and subtract. The hardware will do the right thing with any | |
1985 | overflow in the subtraction. */ | |
1986 | if (TREE_CODE (arg0) != INTEGER_CST || TREE_CODE (arg1) != INTEGER_CST) | |
1987 | return size_binop (MINUS_EXPR, convert (ctype, arg0), | |
1988 | convert (ctype, arg1)); | |
1989 | ||
1990 | /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE. | |
1991 | Otherwise, subtract the other way, convert to CTYPE (we know that can't | |
1992 | overflow) and negate (which can't either). Special-case a result | |
1993 | of zero while we're here. */ | |
1994 | if (tree_int_cst_equal (arg0, arg1)) | |
1995 | return convert (ctype, integer_zero_node); | |
1996 | else if (tree_int_cst_lt (arg1, arg0)) | |
1997 | return convert (ctype, size_binop (MINUS_EXPR, arg0, arg1)); | |
1998 | else | |
1999 | return size_binop (MINUS_EXPR, convert (ctype, integer_zero_node), | |
2000 | convert (ctype, size_binop (MINUS_EXPR, arg1, arg0))); | |
697073d9 | 2001 | } |
6d716ca8 | 2002 | \f |
d4b60170 | 2003 | /* This structure is used to communicate arguments to fold_convert_1. */ |
a4d3481d KG |
2004 | struct fc_args |
2005 | { | |
30f7a378 KH |
2006 | tree arg1; /* Input: value to convert. */ |
2007 | tree type; /* Input: type to convert value to. */ | |
2008 | tree t; /* Ouput: result of conversion. */ | |
a4d3481d KG |
2009 | }; |
2010 | ||
d4b60170 RK |
2011 | /* Function to convert floating-point constants, protected by floating |
2012 | point exception handler. */ | |
2013 | ||
a4d3481d KG |
2014 | static void |
2015 | fold_convert_1 (data) | |
b6cc0a72 | 2016 | PTR data; |
a4d3481d | 2017 | { |
b6cc0a72 | 2018 | struct fc_args *args = (struct fc_args *) data; |
a4d3481d KG |
2019 | |
2020 | args->t = build_real (args->type, | |
2021 | real_value_truncate (TYPE_MODE (args->type), | |
2022 | TREE_REAL_CST (args->arg1))); | |
2023 | } | |
2024 | ||
6d716ca8 RS |
2025 | /* Given T, a tree representing type conversion of ARG1, a constant, |
2026 | return a constant tree representing the result of conversion. */ | |
2027 | ||
2028 | static tree | |
2029 | fold_convert (t, arg1) | |
2030 | register tree t; | |
2031 | register tree arg1; | |
2032 | { | |
2033 | register tree type = TREE_TYPE (t); | |
649ff3b4 | 2034 | int overflow = 0; |
6d716ca8 | 2035 | |
e5e809f4 | 2036 | if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)) |
6d716ca8 RS |
2037 | { |
2038 | if (TREE_CODE (arg1) == INTEGER_CST) | |
2039 | { | |
e3374525 RK |
2040 | /* If we would build a constant wider than GCC supports, |
2041 | leave the conversion unfolded. */ | |
2042 | if (TYPE_PRECISION (type) > 2 * HOST_BITS_PER_WIDE_INT) | |
2043 | return t; | |
2044 | ||
fed3cef0 RK |
2045 | /* If we are trying to make a sizetype for a small integer, use |
2046 | size_int to pick up cached types to reduce duplicate nodes. */ | |
55560b9d | 2047 | if (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type) |
ac50176d | 2048 | && !TREE_CONSTANT_OVERFLOW (arg1) |
770ae6cc | 2049 | && compare_tree_int (arg1, 10000) < 0) |
fed3cef0 RK |
2050 | return size_int_type_wide (TREE_INT_CST_LOW (arg1), type); |
2051 | ||
6d716ca8 RS |
2052 | /* Given an integer constant, make new constant with new type, |
2053 | appropriately sign-extended or truncated. */ | |
2054 | t = build_int_2 (TREE_INT_CST_LOW (arg1), | |
2055 | TREE_INT_CST_HIGH (arg1)); | |
2056 | TREE_TYPE (t) = type; | |
e0f776fb | 2057 | /* Indicate an overflow if (1) ARG1 already overflowed, |
dc3907c5 PE |
2058 | or (2) force_fit_type indicates an overflow. |
2059 | Tell force_fit_type that an overflow has already occurred | |
b472527b JL |
2060 | if ARG1 is a too-large unsigned value and T is signed. |
2061 | But don't indicate an overflow if converting a pointer. */ | |
dc3907c5 | 2062 | TREE_OVERFLOW (t) |
e5e809f4 JL |
2063 | = ((force_fit_type (t, |
2064 | (TREE_INT_CST_HIGH (arg1) < 0 | |
4f242db3 | 2065 | && (TREE_UNSIGNED (type) |
e5e809f4 JL |
2066 | < TREE_UNSIGNED (TREE_TYPE (arg1))))) |
2067 | && ! POINTER_TYPE_P (TREE_TYPE (arg1))) | |
2068 | || TREE_OVERFLOW (arg1)); | |
dc3907c5 PE |
2069 | TREE_CONSTANT_OVERFLOW (t) |
2070 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
6d716ca8 RS |
2071 | } |
2072 | #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) | |
2073 | else if (TREE_CODE (arg1) == REAL_CST) | |
2074 | { | |
4b8a0062 RK |
2075 | /* Don't initialize these, use assignments. |
2076 | Initialized local aggregates don't work on old compilers. */ | |
2077 | REAL_VALUE_TYPE x; | |
2078 | REAL_VALUE_TYPE l; | |
2079 | REAL_VALUE_TYPE u; | |
7cb6a121 | 2080 | tree type1 = TREE_TYPE (arg1); |
e1ee5cdc | 2081 | int no_upper_bound; |
4b8a0062 RK |
2082 | |
2083 | x = TREE_REAL_CST (arg1); | |
7cb6a121 | 2084 | l = real_value_from_int_cst (type1, TYPE_MIN_VALUE (type)); |
e1ee5cdc RH |
2085 | |
2086 | no_upper_bound = (TYPE_MAX_VALUE (type) == NULL); | |
2087 | if (!no_upper_bound) | |
2088 | u = real_value_from_int_cst (type1, TYPE_MAX_VALUE (type)); | |
2089 | ||
4b3d5ea0 RS |
2090 | /* See if X will be in range after truncation towards 0. |
2091 | To compensate for truncation, move the bounds away from 0, | |
2092 | but reject if X exactly equals the adjusted bounds. */ | |
2093 | #ifdef REAL_ARITHMETIC | |
2094 | REAL_ARITHMETIC (l, MINUS_EXPR, l, dconst1); | |
e1ee5cdc RH |
2095 | if (!no_upper_bound) |
2096 | REAL_ARITHMETIC (u, PLUS_EXPR, u, dconst1); | |
4b3d5ea0 RS |
2097 | #else |
2098 | l--; | |
e1ee5cdc RH |
2099 | if (!no_upper_bound) |
2100 | u++; | |
4b3d5ea0 | 2101 | #endif |
5f610074 RK |
2102 | /* If X is a NaN, use zero instead and show we have an overflow. |
2103 | Otherwise, range check. */ | |
2104 | if (REAL_VALUE_ISNAN (x)) | |
2105 | overflow = 1, x = dconst0; | |
e1ee5cdc RH |
2106 | else if (! (REAL_VALUES_LESS (l, x) |
2107 | && !no_upper_bound | |
2108 | && REAL_VALUES_LESS (x, u))) | |
649ff3b4 RK |
2109 | overflow = 1; |
2110 | ||
6d716ca8 RS |
2111 | #ifndef REAL_ARITHMETIC |
2112 | { | |
906c4e36 RK |
2113 | HOST_WIDE_INT low, high; |
2114 | HOST_WIDE_INT half_word | |
2115 | = (HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2); | |
6d716ca8 | 2116 | |
5f610074 RK |
2117 | if (x < 0) |
2118 | x = -x; | |
6d716ca8 | 2119 | |
5f610074 RK |
2120 | high = (HOST_WIDE_INT) (x / half_word / half_word); |
2121 | x -= (REAL_VALUE_TYPE) high * half_word * half_word; | |
2122 | if (x >= (REAL_VALUE_TYPE) half_word * half_word / 2) | |
b6b19f41 | 2123 | { |
5f610074 | 2124 | low = x - (REAL_VALUE_TYPE) half_word * half_word / 2; |
e0f776fb | 2125 | low |= (HOST_WIDE_INT) -1 << (HOST_BITS_PER_WIDE_INT - 1); |
b6b19f41 RS |
2126 | } |
2127 | else | |
5f610074 | 2128 | low = (HOST_WIDE_INT) x; |
6d716ca8 RS |
2129 | if (TREE_REAL_CST (arg1) < 0) |
2130 | neg_double (low, high, &low, &high); | |
2131 | t = build_int_2 (low, high); | |
2132 | } | |
2133 | #else | |
2134 | { | |
906c4e36 | 2135 | HOST_WIDE_INT low, high; |
5f610074 | 2136 | REAL_VALUE_TO_INT (&low, &high, x); |
6d716ca8 RS |
2137 | t = build_int_2 (low, high); |
2138 | } | |
2139 | #endif | |
2140 | TREE_TYPE (t) = type; | |
649ff3b4 RK |
2141 | TREE_OVERFLOW (t) |
2142 | = TREE_OVERFLOW (arg1) | force_fit_type (t, overflow); | |
2143 | TREE_CONSTANT_OVERFLOW (t) | |
2144 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
6d716ca8 RS |
2145 | } |
2146 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
2147 | TREE_TYPE (t) = type; | |
2148 | } | |
2149 | else if (TREE_CODE (type) == REAL_TYPE) | |
2150 | { | |
2151 | #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) | |
2152 | if (TREE_CODE (arg1) == INTEGER_CST) | |
2153 | return build_real_from_int_cst (type, arg1); | |
2154 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
2155 | if (TREE_CODE (arg1) == REAL_CST) | |
7c7b029d | 2156 | { |
a4d3481d | 2157 | struct fc_args args; |
b6cc0a72 | 2158 | |
5f610074 | 2159 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))) |
a377ff85 RK |
2160 | { |
2161 | t = arg1; | |
2162 | TREE_TYPE (arg1) = type; | |
2163 | return t; | |
2164 | } | |
a4d3481d KG |
2165 | |
2166 | /* Setup input for fold_convert_1() */ | |
2167 | args.arg1 = arg1; | |
2168 | args.type = type; | |
b6cc0a72 | 2169 | |
a4d3481d KG |
2170 | if (do_float_handler (fold_convert_1, (PTR) &args)) |
2171 | { | |
2172 | /* Receive output from fold_convert_1() */ | |
2173 | t = args.t; | |
2174 | } | |
2175 | else | |
7c7b029d | 2176 | { |
a4d3481d | 2177 | /* We got an exception from fold_convert_1() */ |
649ff3b4 RK |
2178 | overflow = 1; |
2179 | t = copy_node (arg1); | |
7c7b029d | 2180 | } |
649ff3b4 | 2181 | |
649ff3b4 RK |
2182 | TREE_OVERFLOW (t) |
2183 | = TREE_OVERFLOW (arg1) | force_fit_type (t, overflow); | |
2184 | TREE_CONSTANT_OVERFLOW (t) | |
2185 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
7c7b029d RS |
2186 | return t; |
2187 | } | |
6d716ca8 RS |
2188 | } |
2189 | TREE_CONSTANT (t) = 1; | |
2190 | return t; | |
2191 | } | |
2192 | \f | |
ff59bfe6 | 2193 | /* Return an expr equal to X but certainly not valid as an lvalue. */ |
6d716ca8 RS |
2194 | |
2195 | tree | |
2196 | non_lvalue (x) | |
2197 | tree x; | |
2198 | { | |
2199 | tree result; | |
2200 | ||
2201 | /* These things are certainly not lvalues. */ | |
2202 | if (TREE_CODE (x) == NON_LVALUE_EXPR | |
2203 | || TREE_CODE (x) == INTEGER_CST | |
2204 | || TREE_CODE (x) == REAL_CST | |
2205 | || TREE_CODE (x) == STRING_CST | |
2206 | || TREE_CODE (x) == ADDR_EXPR) | |
ff59bfe6 | 2207 | return x; |
6d716ca8 RS |
2208 | |
2209 | result = build1 (NON_LVALUE_EXPR, TREE_TYPE (x), x); | |
2210 | TREE_CONSTANT (result) = TREE_CONSTANT (x); | |
2211 | return result; | |
2212 | } | |
a5e9b124 | 2213 | |
e9866da3 JM |
2214 | /* Nonzero means lvalues are limited to those valid in pedantic ANSI C. |
2215 | Zero means allow extended lvalues. */ | |
2216 | ||
2217 | int pedantic_lvalues; | |
2218 | ||
a5e9b124 JW |
2219 | /* When pedantic, return an expr equal to X but certainly not valid as a |
2220 | pedantic lvalue. Otherwise, return X. */ | |
2221 | ||
2222 | tree | |
2223 | pedantic_non_lvalue (x) | |
2224 | tree x; | |
2225 | { | |
e9866da3 | 2226 | if (pedantic_lvalues) |
a5e9b124 JW |
2227 | return non_lvalue (x); |
2228 | else | |
2229 | return x; | |
2230 | } | |
c05a9b68 RS |
2231 | \f |
2232 | /* Given a tree comparison code, return the code that is the logical inverse | |
2233 | of the given code. It is not safe to do this for floating-point | |
2234 | comparisons, except for NE_EXPR and EQ_EXPR. */ | |
6d716ca8 | 2235 | |
c05a9b68 RS |
2236 | static enum tree_code |
2237 | invert_tree_comparison (code) | |
2238 | enum tree_code code; | |
2239 | { | |
2240 | switch (code) | |
2241 | { | |
2242 | case EQ_EXPR: | |
2243 | return NE_EXPR; | |
2244 | case NE_EXPR: | |
2245 | return EQ_EXPR; | |
2246 | case GT_EXPR: | |
2247 | return LE_EXPR; | |
2248 | case GE_EXPR: | |
2249 | return LT_EXPR; | |
2250 | case LT_EXPR: | |
2251 | return GE_EXPR; | |
2252 | case LE_EXPR: | |
2253 | return GT_EXPR; | |
2254 | default: | |
2255 | abort (); | |
2256 | } | |
2257 | } | |
2258 | ||
2259 | /* Similar, but return the comparison that results if the operands are | |
2260 | swapped. This is safe for floating-point. */ | |
2261 | ||
2262 | static enum tree_code | |
2263 | swap_tree_comparison (code) | |
2264 | enum tree_code code; | |
2265 | { | |
2266 | switch (code) | |
2267 | { | |
2268 | case EQ_EXPR: | |
2269 | case NE_EXPR: | |
2270 | return code; | |
2271 | case GT_EXPR: | |
2272 | return LT_EXPR; | |
2273 | case GE_EXPR: | |
2274 | return LE_EXPR; | |
2275 | case LT_EXPR: | |
2276 | return GT_EXPR; | |
2277 | case LE_EXPR: | |
2278 | return GE_EXPR; | |
2279 | default: | |
2280 | abort (); | |
2281 | } | |
2282 | } | |
61f275ff RK |
2283 | |
2284 | /* Return nonzero if CODE is a tree code that represents a truth value. */ | |
2285 | ||
2286 | static int | |
2287 | truth_value_p (code) | |
2288 | enum tree_code code; | |
2289 | { | |
2290 | return (TREE_CODE_CLASS (code) == '<' | |
2291 | || code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR | |
2292 | || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR | |
2293 | || code == TRUTH_XOR_EXPR || code == TRUTH_NOT_EXPR); | |
2294 | } | |
c05a9b68 | 2295 | \f |
6a1746af RS |
2296 | /* Return nonzero if two operands are necessarily equal. |
2297 | If ONLY_CONST is non-zero, only return non-zero for constants. | |
2298 | This function tests whether the operands are indistinguishable; | |
2299 | it does not test whether they are equal using C's == operation. | |
2300 | The distinction is important for IEEE floating point, because | |
2301 | (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and | |
2302 | (2) two NaNs may be indistinguishable, but NaN!=NaN. */ | |
6d716ca8 RS |
2303 | |
2304 | int | |
2305 | operand_equal_p (arg0, arg1, only_const) | |
2306 | tree arg0, arg1; | |
2307 | int only_const; | |
2308 | { | |
2309 | /* If both types don't have the same signedness, then we can't consider | |
2310 | them equal. We must check this before the STRIP_NOPS calls | |
2311 | because they may change the signedness of the arguments. */ | |
2312 | if (TREE_UNSIGNED (TREE_TYPE (arg0)) != TREE_UNSIGNED (TREE_TYPE (arg1))) | |
2313 | return 0; | |
2314 | ||
2315 | STRIP_NOPS (arg0); | |
2316 | STRIP_NOPS (arg1); | |
2317 | ||
c7cfe938 RK |
2318 | if (TREE_CODE (arg0) != TREE_CODE (arg1) |
2319 | /* This is needed for conversions and for COMPONENT_REF. | |
2320 | Might as well play it safe and always test this. */ | |
e89a9554 ZW |
2321 | || TREE_CODE (TREE_TYPE (arg0)) == ERROR_MARK |
2322 | || TREE_CODE (TREE_TYPE (arg1)) == ERROR_MARK | |
c7cfe938 | 2323 | || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1))) |
6d716ca8 RS |
2324 | return 0; |
2325 | ||
c7cfe938 RK |
2326 | /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal. |
2327 | We don't care about side effects in that case because the SAVE_EXPR | |
2328 | takes care of that for us. In all other cases, two expressions are | |
2329 | equal if they have no side effects. If we have two identical | |
2330 | expressions with side effects that should be treated the same due | |
2331 | to the only side effects being identical SAVE_EXPR's, that will | |
2332 | be detected in the recursive calls below. */ | |
2333 | if (arg0 == arg1 && ! only_const | |
2334 | && (TREE_CODE (arg0) == SAVE_EXPR | |
2335 | || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1)))) | |
6d716ca8 RS |
2336 | return 1; |
2337 | ||
c7cfe938 RK |
2338 | /* Next handle constant cases, those for which we can return 1 even |
2339 | if ONLY_CONST is set. */ | |
2340 | if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1)) | |
2341 | switch (TREE_CODE (arg0)) | |
2342 | { | |
2343 | case INTEGER_CST: | |
3c9b0091 RK |
2344 | return (! TREE_CONSTANT_OVERFLOW (arg0) |
2345 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
05bccae2 | 2346 | && tree_int_cst_equal (arg0, arg1)); |
c7cfe938 RK |
2347 | |
2348 | case REAL_CST: | |
3c9b0091 RK |
2349 | return (! TREE_CONSTANT_OVERFLOW (arg0) |
2350 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
41c9120b PE |
2351 | && REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0), |
2352 | TREE_REAL_CST (arg1))); | |
c7cfe938 RK |
2353 | |
2354 | case COMPLEX_CST: | |
2355 | return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1), | |
2356 | only_const) | |
2357 | && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1), | |
2358 | only_const)); | |
2359 | ||
2360 | case STRING_CST: | |
2361 | return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1) | |
71145810 | 2362 | && ! memcmp (TREE_STRING_POINTER (arg0), |
c7cfe938 RK |
2363 | TREE_STRING_POINTER (arg1), |
2364 | TREE_STRING_LENGTH (arg0))); | |
2365 | ||
2366 | case ADDR_EXPR: | |
2367 | return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), | |
2368 | 0); | |
e9a25f70 JL |
2369 | default: |
2370 | break; | |
c7cfe938 | 2371 | } |
6d716ca8 RS |
2372 | |
2373 | if (only_const) | |
2374 | return 0; | |
2375 | ||
6d716ca8 RS |
2376 | switch (TREE_CODE_CLASS (TREE_CODE (arg0))) |
2377 | { | |
2378 | case '1': | |
2379 | /* Two conversions are equal only if signedness and modes match. */ | |
2380 | if ((TREE_CODE (arg0) == NOP_EXPR || TREE_CODE (arg0) == CONVERT_EXPR) | |
2381 | && (TREE_UNSIGNED (TREE_TYPE (arg0)) | |
2382 | != TREE_UNSIGNED (TREE_TYPE (arg1)))) | |
2383 | return 0; | |
2384 | ||
2385 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
2386 | TREE_OPERAND (arg1, 0), 0); | |
2387 | ||
2388 | case '<': | |
2389 | case '2': | |
c7cfe938 RK |
2390 | if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0) |
2391 | && operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), | |
2392 | 0)) | |
2393 | return 1; | |
2394 | ||
2395 | /* For commutative ops, allow the other order. */ | |
2396 | return ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MULT_EXPR | |
2397 | || TREE_CODE (arg0) == MIN_EXPR || TREE_CODE (arg0) == MAX_EXPR | |
2398 | || TREE_CODE (arg0) == BIT_IOR_EXPR | |
2399 | || TREE_CODE (arg0) == BIT_XOR_EXPR | |
2400 | || TREE_CODE (arg0) == BIT_AND_EXPR | |
2401 | || TREE_CODE (arg0) == NE_EXPR || TREE_CODE (arg0) == EQ_EXPR) | |
2402 | && operand_equal_p (TREE_OPERAND (arg0, 0), | |
2403 | TREE_OPERAND (arg1, 1), 0) | |
6d716ca8 | 2404 | && operand_equal_p (TREE_OPERAND (arg0, 1), |
c7cfe938 | 2405 | TREE_OPERAND (arg1, 0), 0)); |
6d716ca8 RS |
2406 | |
2407 | case 'r': | |
05ca5990 | 2408 | /* If either of the pointer (or reference) expressions we are dereferencing |
30f7a378 | 2409 | contain a side effect, these cannot be equal. */ |
05ca5990 GRK |
2410 | if (TREE_SIDE_EFFECTS (arg0) |
2411 | || TREE_SIDE_EFFECTS (arg1)) | |
2412 | return 0; | |
2413 | ||
6d716ca8 RS |
2414 | switch (TREE_CODE (arg0)) |
2415 | { | |
2416 | case INDIRECT_REF: | |
2417 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
2418 | TREE_OPERAND (arg1, 0), 0); | |
2419 | ||
2420 | case COMPONENT_REF: | |
2421 | case ARRAY_REF: | |
b4e3fabb | 2422 | case ARRAY_RANGE_REF: |
6d716ca8 RS |
2423 | return (operand_equal_p (TREE_OPERAND (arg0, 0), |
2424 | TREE_OPERAND (arg1, 0), 0) | |
2425 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
2426 | TREE_OPERAND (arg1, 1), 0)); | |
2427 | ||
2428 | case BIT_FIELD_REF: | |
2429 | return (operand_equal_p (TREE_OPERAND (arg0, 0), | |
2430 | TREE_OPERAND (arg1, 0), 0) | |
2431 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
2432 | TREE_OPERAND (arg1, 1), 0) | |
2433 | && operand_equal_p (TREE_OPERAND (arg0, 2), | |
2434 | TREE_OPERAND (arg1, 2), 0)); | |
e9a25f70 JL |
2435 | default: |
2436 | return 0; | |
6d716ca8 | 2437 | } |
45f97e2e RH |
2438 | |
2439 | case 'e': | |
2440 | if (TREE_CODE (arg0) == RTL_EXPR) | |
2441 | return rtx_equal_p (RTL_EXPR_RTL (arg0), RTL_EXPR_RTL (arg1)); | |
2442 | return 0; | |
b6cc0a72 | 2443 | |
e9a25f70 JL |
2444 | default: |
2445 | return 0; | |
6d716ca8 | 2446 | } |
6d716ca8 | 2447 | } |
c05a9b68 RS |
2448 | \f |
2449 | /* Similar to operand_equal_p, but see if ARG0 might have been made by | |
b6cc0a72 | 2450 | shorten_compare from ARG1 when ARG1 was being compared with OTHER. |
6d716ca8 | 2451 | |
6d716ca8 RS |
2452 | When in doubt, return 0. */ |
2453 | ||
b6cc0a72 | 2454 | static int |
c05a9b68 RS |
2455 | operand_equal_for_comparison_p (arg0, arg1, other) |
2456 | tree arg0, arg1; | |
2457 | tree other; | |
6d716ca8 | 2458 | { |
c05a9b68 | 2459 | int unsignedp1, unsignedpo; |
52de9b6c | 2460 | tree primarg0, primarg1, primother; |
770ae6cc | 2461 | unsigned int correct_width; |
6d716ca8 | 2462 | |
c05a9b68 | 2463 | if (operand_equal_p (arg0, arg1, 0)) |
6d716ca8 RS |
2464 | return 1; |
2465 | ||
0982a4b8 JM |
2466 | if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0)) |
2467 | || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1))) | |
6d716ca8 RS |
2468 | return 0; |
2469 | ||
52de9b6c RK |
2470 | /* Discard any conversions that don't change the modes of ARG0 and ARG1 |
2471 | and see if the inner values are the same. This removes any | |
2472 | signedness comparison, which doesn't matter here. */ | |
2473 | primarg0 = arg0, primarg1 = arg1; | |
b6cc0a72 KH |
2474 | STRIP_NOPS (primarg0); |
2475 | STRIP_NOPS (primarg1); | |
52de9b6c RK |
2476 | if (operand_equal_p (primarg0, primarg1, 0)) |
2477 | return 1; | |
2478 | ||
c05a9b68 RS |
2479 | /* Duplicate what shorten_compare does to ARG1 and see if that gives the |
2480 | actual comparison operand, ARG0. | |
6d716ca8 | 2481 | |
c05a9b68 | 2482 | First throw away any conversions to wider types |
6d716ca8 | 2483 | already present in the operands. */ |
6d716ca8 | 2484 | |
c05a9b68 RS |
2485 | primarg1 = get_narrower (arg1, &unsignedp1); |
2486 | primother = get_narrower (other, &unsignedpo); | |
2487 | ||
2488 | correct_width = TYPE_PRECISION (TREE_TYPE (arg1)); | |
2489 | if (unsignedp1 == unsignedpo | |
2490 | && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width | |
2491 | && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width) | |
6d716ca8 | 2492 | { |
c05a9b68 | 2493 | tree type = TREE_TYPE (arg0); |
6d716ca8 RS |
2494 | |
2495 | /* Make sure shorter operand is extended the right way | |
2496 | to match the longer operand. */ | |
c05a9b68 | 2497 | primarg1 = convert (signed_or_unsigned_type (unsignedp1, |
b6cc0a72 KH |
2498 | TREE_TYPE (primarg1)), |
2499 | primarg1); | |
6d716ca8 | 2500 | |
c05a9b68 | 2501 | if (operand_equal_p (arg0, convert (type, primarg1), 0)) |
6d716ca8 RS |
2502 | return 1; |
2503 | } | |
2504 | ||
2505 | return 0; | |
2506 | } | |
2507 | \f | |
f72aed24 | 2508 | /* See if ARG is an expression that is either a comparison or is performing |
c05a9b68 RS |
2509 | arithmetic on comparisons. The comparisons must only be comparing |
2510 | two different values, which will be stored in *CVAL1 and *CVAL2; if | |
2511 | they are non-zero it means that some operands have already been found. | |
2512 | No variables may be used anywhere else in the expression except in the | |
35e66bd1 RK |
2513 | comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around |
2514 | the expression and save_expr needs to be called with CVAL1 and CVAL2. | |
c05a9b68 RS |
2515 | |
2516 | If this is true, return 1. Otherwise, return zero. */ | |
2517 | ||
2518 | static int | |
35e66bd1 | 2519 | twoval_comparison_p (arg, cval1, cval2, save_p) |
c05a9b68 RS |
2520 | tree arg; |
2521 | tree *cval1, *cval2; | |
35e66bd1 | 2522 | int *save_p; |
c05a9b68 RS |
2523 | { |
2524 | enum tree_code code = TREE_CODE (arg); | |
2525 | char class = TREE_CODE_CLASS (code); | |
2526 | ||
2527 | /* We can handle some of the 'e' cases here. */ | |
35e66bd1 | 2528 | if (class == 'e' && code == TRUTH_NOT_EXPR) |
c05a9b68 RS |
2529 | class = '1'; |
2530 | else if (class == 'e' | |
2531 | && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR | |
2532 | || code == COMPOUND_EXPR)) | |
2533 | class = '2'; | |
2315a5db | 2534 | |
d4b60170 RK |
2535 | else if (class == 'e' && code == SAVE_EXPR && SAVE_EXPR_RTL (arg) == 0 |
2536 | && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0))) | |
35e66bd1 RK |
2537 | { |
2538 | /* If we've already found a CVAL1 or CVAL2, this expression is | |
2539 | two complex to handle. */ | |
2540 | if (*cval1 || *cval2) | |
2541 | return 0; | |
2542 | ||
2543 | class = '1'; | |
2544 | *save_p = 1; | |
2545 | } | |
c05a9b68 RS |
2546 | |
2547 | switch (class) | |
2548 | { | |
2549 | case '1': | |
35e66bd1 | 2550 | return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p); |
c05a9b68 RS |
2551 | |
2552 | case '2': | |
35e66bd1 RK |
2553 | return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p) |
2554 | && twoval_comparison_p (TREE_OPERAND (arg, 1), | |
2555 | cval1, cval2, save_p)); | |
c05a9b68 RS |
2556 | |
2557 | case 'c': | |
2558 | return 1; | |
2559 | ||
2560 | case 'e': | |
2561 | if (code == COND_EXPR) | |
35e66bd1 RK |
2562 | return (twoval_comparison_p (TREE_OPERAND (arg, 0), |
2563 | cval1, cval2, save_p) | |
2564 | && twoval_comparison_p (TREE_OPERAND (arg, 1), | |
2565 | cval1, cval2, save_p) | |
c05a9b68 | 2566 | && twoval_comparison_p (TREE_OPERAND (arg, 2), |
35e66bd1 | 2567 | cval1, cval2, save_p)); |
c05a9b68 | 2568 | return 0; |
b6cc0a72 | 2569 | |
c05a9b68 RS |
2570 | case '<': |
2571 | /* First see if we can handle the first operand, then the second. For | |
2572 | the second operand, we know *CVAL1 can't be zero. It must be that | |
2573 | one side of the comparison is each of the values; test for the | |
2574 | case where this isn't true by failing if the two operands | |
2575 | are the same. */ | |
2576 | ||
2577 | if (operand_equal_p (TREE_OPERAND (arg, 0), | |
2578 | TREE_OPERAND (arg, 1), 0)) | |
2579 | return 0; | |
2580 | ||
2581 | if (*cval1 == 0) | |
2582 | *cval1 = TREE_OPERAND (arg, 0); | |
2583 | else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0)) | |
2584 | ; | |
2585 | else if (*cval2 == 0) | |
2586 | *cval2 = TREE_OPERAND (arg, 0); | |
2587 | else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0)) | |
2588 | ; | |
2589 | else | |
2590 | return 0; | |
2591 | ||
2592 | if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0)) | |
2593 | ; | |
2594 | else if (*cval2 == 0) | |
2595 | *cval2 = TREE_OPERAND (arg, 1); | |
2596 | else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0)) | |
2597 | ; | |
2598 | else | |
2599 | return 0; | |
2600 | ||
2601 | return 1; | |
c05a9b68 | 2602 | |
e9a25f70 JL |
2603 | default: |
2604 | return 0; | |
2605 | } | |
c05a9b68 RS |
2606 | } |
2607 | \f | |
2608 | /* ARG is a tree that is known to contain just arithmetic operations and | |
2609 | comparisons. Evaluate the operations in the tree substituting NEW0 for | |
f72aed24 | 2610 | any occurrence of OLD0 as an operand of a comparison and likewise for |
c05a9b68 RS |
2611 | NEW1 and OLD1. */ |
2612 | ||
2613 | static tree | |
2614 | eval_subst (arg, old0, new0, old1, new1) | |
2615 | tree arg; | |
2616 | tree old0, new0, old1, new1; | |
2617 | { | |
2618 | tree type = TREE_TYPE (arg); | |
2619 | enum tree_code code = TREE_CODE (arg); | |
2620 | char class = TREE_CODE_CLASS (code); | |
2621 | ||
2622 | /* We can handle some of the 'e' cases here. */ | |
2623 | if (class == 'e' && code == TRUTH_NOT_EXPR) | |
2624 | class = '1'; | |
2625 | else if (class == 'e' | |
2626 | && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)) | |
2627 | class = '2'; | |
2628 | ||
2629 | switch (class) | |
2630 | { | |
2631 | case '1': | |
2632 | return fold (build1 (code, type, | |
2633 | eval_subst (TREE_OPERAND (arg, 0), | |
2634 | old0, new0, old1, new1))); | |
2635 | ||
2636 | case '2': | |
2637 | return fold (build (code, type, | |
2638 | eval_subst (TREE_OPERAND (arg, 0), | |
2639 | old0, new0, old1, new1), | |
2640 | eval_subst (TREE_OPERAND (arg, 1), | |
2641 | old0, new0, old1, new1))); | |
2642 | ||
2643 | case 'e': | |
2644 | switch (code) | |
2645 | { | |
2646 | case SAVE_EXPR: | |
2647 | return eval_subst (TREE_OPERAND (arg, 0), old0, new0, old1, new1); | |
2648 | ||
2649 | case COMPOUND_EXPR: | |
2650 | return eval_subst (TREE_OPERAND (arg, 1), old0, new0, old1, new1); | |
2651 | ||
2652 | case COND_EXPR: | |
2653 | return fold (build (code, type, | |
2654 | eval_subst (TREE_OPERAND (arg, 0), | |
2655 | old0, new0, old1, new1), | |
2656 | eval_subst (TREE_OPERAND (arg, 1), | |
2657 | old0, new0, old1, new1), | |
2658 | eval_subst (TREE_OPERAND (arg, 2), | |
2659 | old0, new0, old1, new1))); | |
e9a25f70 JL |
2660 | default: |
2661 | break; | |
c05a9b68 | 2662 | } |
e45ed4de | 2663 | /* fall through - ??? */ |
c05a9b68 RS |
2664 | |
2665 | case '<': | |
2666 | { | |
2667 | tree arg0 = TREE_OPERAND (arg, 0); | |
2668 | tree arg1 = TREE_OPERAND (arg, 1); | |
2669 | ||
2670 | /* We need to check both for exact equality and tree equality. The | |
2671 | former will be true if the operand has a side-effect. In that | |
2672 | case, we know the operand occurred exactly once. */ | |
2673 | ||
2674 | if (arg0 == old0 || operand_equal_p (arg0, old0, 0)) | |
2675 | arg0 = new0; | |
2676 | else if (arg0 == old1 || operand_equal_p (arg0, old1, 0)) | |
2677 | arg0 = new1; | |
2678 | ||
2679 | if (arg1 == old0 || operand_equal_p (arg1, old0, 0)) | |
2680 | arg1 = new0; | |
2681 | else if (arg1 == old1 || operand_equal_p (arg1, old1, 0)) | |
2682 | arg1 = new1; | |
2683 | ||
2684 | return fold (build (code, type, arg0, arg1)); | |
2685 | } | |
c05a9b68 | 2686 | |
e9a25f70 JL |
2687 | default: |
2688 | return arg; | |
2689 | } | |
c05a9b68 RS |
2690 | } |
2691 | \f | |
6d716ca8 RS |
2692 | /* Return a tree for the case when the result of an expression is RESULT |
2693 | converted to TYPE and OMITTED was previously an operand of the expression | |
2694 | but is now not needed (e.g., we folded OMITTED * 0). | |
2695 | ||
2696 | If OMITTED has side effects, we must evaluate it. Otherwise, just do | |
2697 | the conversion of RESULT to TYPE. */ | |
2698 | ||
2699 | static tree | |
2700 | omit_one_operand (type, result, omitted) | |
2701 | tree type, result, omitted; | |
2702 | { | |
2703 | tree t = convert (type, result); | |
2704 | ||
2705 | if (TREE_SIDE_EFFECTS (omitted)) | |
2706 | return build (COMPOUND_EXPR, type, omitted, t); | |
2707 | ||
d023bff9 | 2708 | return non_lvalue (t); |
6d716ca8 | 2709 | } |
4ab3cb65 RK |
2710 | |
2711 | /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */ | |
2712 | ||
2713 | static tree | |
2714 | pedantic_omit_one_operand (type, result, omitted) | |
2715 | tree type, result, omitted; | |
2716 | { | |
2717 | tree t = convert (type, result); | |
2718 | ||
2719 | if (TREE_SIDE_EFFECTS (omitted)) | |
2720 | return build (COMPOUND_EXPR, type, omitted, t); | |
2721 | ||
2722 | return pedantic_non_lvalue (t); | |
2723 | } | |
6d716ca8 | 2724 | \f |
3f783329 RS |
2725 | /* Return a simplified tree node for the truth-negation of ARG. This |
2726 | never alters ARG itself. We assume that ARG is an operation that | |
6d716ca8 RS |
2727 | returns a truth value (0 or 1). */ |
2728 | ||
2729 | tree | |
2730 | invert_truthvalue (arg) | |
2731 | tree arg; | |
2732 | { | |
2733 | tree type = TREE_TYPE (arg); | |
c05a9b68 | 2734 | enum tree_code code = TREE_CODE (arg); |
6d716ca8 | 2735 | |
8ac1abdf JW |
2736 | if (code == ERROR_MARK) |
2737 | return arg; | |
2738 | ||
c05a9b68 RS |
2739 | /* If this is a comparison, we can simply invert it, except for |
2740 | floating-point non-equality comparisons, in which case we just | |
2741 | enclose a TRUTH_NOT_EXPR around what we have. */ | |
6d716ca8 | 2742 | |
c05a9b68 | 2743 | if (TREE_CODE_CLASS (code) == '<') |
6d716ca8 | 2744 | { |
7178e3af | 2745 | if (FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg, 0))) |
de6c5979 BL |
2746 | && !flag_unsafe_math_optimizations |
2747 | && code != NE_EXPR | |
2748 | && code != EQ_EXPR) | |
c05a9b68 RS |
2749 | return build1 (TRUTH_NOT_EXPR, type, arg); |
2750 | else | |
ca46db87 | 2751 | return build (invert_tree_comparison (code), type, |
3f783329 | 2752 | TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1)); |
c05a9b68 | 2753 | } |
6d716ca8 | 2754 | |
c05a9b68 RS |
2755 | switch (code) |
2756 | { | |
6d716ca8 | 2757 | case INTEGER_CST: |
05bccae2 | 2758 | return convert (type, build_int_2 (integer_zerop (arg), 0)); |
6d716ca8 RS |
2759 | |
2760 | case TRUTH_AND_EXPR: | |
2761 | return build (TRUTH_OR_EXPR, type, | |
2762 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2763 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2764 | ||
2765 | case TRUTH_OR_EXPR: | |
2766 | return build (TRUTH_AND_EXPR, type, | |
2767 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2768 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2769 | ||
772447c5 RK |
2770 | case TRUTH_XOR_EXPR: |
2771 | /* Here we can invert either operand. We invert the first operand | |
2772 | unless the second operand is a TRUTH_NOT_EXPR in which case our | |
2773 | result is the XOR of the first operand with the inside of the | |
2774 | negation of the second operand. */ | |
2775 | ||
2776 | if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR) | |
2777 | return build (TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0), | |
2778 | TREE_OPERAND (TREE_OPERAND (arg, 1), 0)); | |
2779 | else | |
2780 | return build (TRUTH_XOR_EXPR, type, | |
2781 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2782 | TREE_OPERAND (arg, 1)); | |
2783 | ||
6d716ca8 RS |
2784 | case TRUTH_ANDIF_EXPR: |
2785 | return build (TRUTH_ORIF_EXPR, type, | |
2786 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2787 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2788 | ||
2789 | case TRUTH_ORIF_EXPR: | |
2790 | return build (TRUTH_ANDIF_EXPR, type, | |
2791 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2792 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2793 | ||
2794 | case TRUTH_NOT_EXPR: | |
2795 | return TREE_OPERAND (arg, 0); | |
2796 | ||
2797 | case COND_EXPR: | |
2798 | return build (COND_EXPR, type, TREE_OPERAND (arg, 0), | |
2799 | invert_truthvalue (TREE_OPERAND (arg, 1)), | |
2800 | invert_truthvalue (TREE_OPERAND (arg, 2))); | |
2801 | ||
ef9fe0da RK |
2802 | case COMPOUND_EXPR: |
2803 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg, 0), | |
2804 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2805 | ||
14a774a9 RK |
2806 | case WITH_RECORD_EXPR: |
2807 | return build (WITH_RECORD_EXPR, type, | |
2808 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2809 | TREE_OPERAND (arg, 1)); | |
2810 | ||
6d716ca8 RS |
2811 | case NON_LVALUE_EXPR: |
2812 | return invert_truthvalue (TREE_OPERAND (arg, 0)); | |
2813 | ||
2814 | case NOP_EXPR: | |
2815 | case CONVERT_EXPR: | |
2816 | case FLOAT_EXPR: | |
2817 | return build1 (TREE_CODE (arg), type, | |
2818 | invert_truthvalue (TREE_OPERAND (arg, 0))); | |
2819 | ||
2820 | case BIT_AND_EXPR: | |
efc1a4d9 PB |
2821 | if (!integer_onep (TREE_OPERAND (arg, 1))) |
2822 | break; | |
6d716ca8 | 2823 | return build (EQ_EXPR, type, arg, convert (type, integer_zero_node)); |
6d716ca8 | 2824 | |
dfa90b42 RS |
2825 | case SAVE_EXPR: |
2826 | return build1 (TRUTH_NOT_EXPR, type, arg); | |
a25ee332 RK |
2827 | |
2828 | case CLEANUP_POINT_EXPR: | |
2829 | return build1 (CLEANUP_POINT_EXPR, type, | |
2830 | invert_truthvalue (TREE_OPERAND (arg, 0))); | |
e9a25f70 JL |
2831 | |
2832 | default: | |
2833 | break; | |
efc1a4d9 PB |
2834 | } |
2835 | if (TREE_CODE (TREE_TYPE (arg)) != BOOLEAN_TYPE) | |
dfa90b42 | 2836 | abort (); |
efc1a4d9 | 2837 | return build1 (TRUTH_NOT_EXPR, type, arg); |
6d716ca8 RS |
2838 | } |
2839 | ||
2840 | /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both | |
2841 | operands are another bit-wise operation with a common input. If so, | |
2842 | distribute the bit operations to save an operation and possibly two if | |
2843 | constants are involved. For example, convert | |
2844 | (A | B) & (A | C) into A | (B & C) | |
2845 | Further simplification will occur if B and C are constants. | |
2846 | ||
2847 | If this optimization cannot be done, 0 will be returned. */ | |
2848 | ||
2849 | static tree | |
2850 | distribute_bit_expr (code, type, arg0, arg1) | |
2851 | enum tree_code code; | |
2852 | tree type; | |
2853 | tree arg0, arg1; | |
2854 | { | |
2855 | tree common; | |
2856 | tree left, right; | |
2857 | ||
2858 | if (TREE_CODE (arg0) != TREE_CODE (arg1) | |
2859 | || TREE_CODE (arg0) == code | |
fced8ba3 RS |
2860 | || (TREE_CODE (arg0) != BIT_AND_EXPR |
2861 | && TREE_CODE (arg0) != BIT_IOR_EXPR)) | |
6d716ca8 RS |
2862 | return 0; |
2863 | ||
2864 | if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0)) | |
2865 | { | |
2866 | common = TREE_OPERAND (arg0, 0); | |
2867 | left = TREE_OPERAND (arg0, 1); | |
2868 | right = TREE_OPERAND (arg1, 1); | |
2869 | } | |
2870 | else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0)) | |
2871 | { | |
2872 | common = TREE_OPERAND (arg0, 0); | |
2873 | left = TREE_OPERAND (arg0, 1); | |
2874 | right = TREE_OPERAND (arg1, 0); | |
2875 | } | |
2876 | else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0)) | |
2877 | { | |
2878 | common = TREE_OPERAND (arg0, 1); | |
2879 | left = TREE_OPERAND (arg0, 0); | |
2880 | right = TREE_OPERAND (arg1, 1); | |
2881 | } | |
2882 | else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0)) | |
2883 | { | |
2884 | common = TREE_OPERAND (arg0, 1); | |
2885 | left = TREE_OPERAND (arg0, 0); | |
2886 | right = TREE_OPERAND (arg1, 0); | |
2887 | } | |
2888 | else | |
2889 | return 0; | |
2890 | ||
2891 | return fold (build (TREE_CODE (arg0), type, common, | |
2892 | fold (build (code, type, left, right)))); | |
2893 | } | |
2894 | \f | |
2895 | /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER | |
2896 | starting at BITPOS. The field is unsigned if UNSIGNEDP is non-zero. */ | |
2897 | ||
2898 | static tree | |
2899 | make_bit_field_ref (inner, type, bitsize, bitpos, unsignedp) | |
2900 | tree inner; | |
2901 | tree type; | |
2902 | int bitsize, bitpos; | |
2903 | int unsignedp; | |
2904 | { | |
2905 | tree result = build (BIT_FIELD_REF, type, inner, | |
06ceef4e | 2906 | size_int (bitsize), bitsize_int (bitpos)); |
6d716ca8 RS |
2907 | |
2908 | TREE_UNSIGNED (result) = unsignedp; | |
2909 | ||
2910 | return result; | |
2911 | } | |
2912 | ||
2913 | /* Optimize a bit-field compare. | |
2914 | ||
2915 | There are two cases: First is a compare against a constant and the | |
2916 | second is a comparison of two items where the fields are at the same | |
2917 | bit position relative to the start of a chunk (byte, halfword, word) | |
2918 | large enough to contain it. In these cases we can avoid the shift | |
2919 | implicit in bitfield extractions. | |
2920 | ||
2921 | For constants, we emit a compare of the shifted constant with the | |
2922 | BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being | |
2923 | compared. For two fields at the same position, we do the ANDs with the | |
2924 | similar mask and compare the result of the ANDs. | |
2925 | ||
2926 | CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR. | |
2927 | COMPARE_TYPE is the type of the comparison, and LHS and RHS | |
2928 | are the left and right operands of the comparison, respectively. | |
2929 | ||
6dc42e49 | 2930 | If the optimization described above can be done, we return the resulting |
6d716ca8 RS |
2931 | tree. Otherwise we return zero. */ |
2932 | ||
2933 | static tree | |
2934 | optimize_bit_field_compare (code, compare_type, lhs, rhs) | |
2935 | enum tree_code code; | |
2936 | tree compare_type; | |
2937 | tree lhs, rhs; | |
2938 | { | |
770ae6cc | 2939 | HOST_WIDE_INT lbitpos, lbitsize, rbitpos, rbitsize, nbitpos, nbitsize; |
6d716ca8 RS |
2940 | tree type = TREE_TYPE (lhs); |
2941 | tree signed_type, unsigned_type; | |
2942 | int const_p = TREE_CODE (rhs) == INTEGER_CST; | |
5826cacf | 2943 | enum machine_mode lmode, rmode, nmode; |
6d716ca8 RS |
2944 | int lunsignedp, runsignedp; |
2945 | int lvolatilep = 0, rvolatilep = 0; | |
770ae6cc | 2946 | unsigned int alignment; |
4e86caed | 2947 | tree linner, rinner = NULL_TREE; |
6d716ca8 | 2948 | tree mask; |
f1e60ec6 | 2949 | tree offset; |
6d716ca8 RS |
2950 | |
2951 | /* Get all the information about the extractions being done. If the bit size | |
2952 | if the same as the size of the underlying object, we aren't doing an | |
14a774a9 RK |
2953 | extraction at all and so can do nothing. We also don't want to |
2954 | do anything if the inner expression is a PLACEHOLDER_EXPR since we | |
2955 | then will no longer be able to replace it. */ | |
f1e60ec6 | 2956 | linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode, |
23bd99ae | 2957 | &lunsignedp, &lvolatilep, &alignment); |
9f5e873c | 2958 | if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0 |
14a774a9 | 2959 | || offset != 0 || TREE_CODE (linner) == PLACEHOLDER_EXPR) |
6d716ca8 RS |
2960 | return 0; |
2961 | ||
2962 | if (!const_p) | |
2963 | { | |
2964 | /* If this is not a constant, we can only do something if bit positions, | |
2965 | sizes, and signedness are the same. */ | |
23bd99ae RK |
2966 | rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode, |
2967 | &runsignedp, &rvolatilep, &alignment); | |
6d716ca8 | 2968 | |
9f5e873c | 2969 | if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize |
14a774a9 RK |
2970 | || lunsignedp != runsignedp || offset != 0 |
2971 | || TREE_CODE (rinner) == PLACEHOLDER_EXPR) | |
6d716ca8 RS |
2972 | return 0; |
2973 | } | |
2974 | ||
2975 | /* See if we can find a mode to refer to this field. We should be able to, | |
2976 | but fail if we can't. */ | |
5826cacf RK |
2977 | nmode = get_best_mode (lbitsize, lbitpos, |
2978 | const_p ? TYPE_ALIGN (TREE_TYPE (linner)) | |
2979 | : MIN (TYPE_ALIGN (TREE_TYPE (linner)), | |
2980 | TYPE_ALIGN (TREE_TYPE (rinner))), | |
2981 | word_mode, lvolatilep || rvolatilep); | |
2982 | if (nmode == VOIDmode) | |
6d716ca8 RS |
2983 | return 0; |
2984 | ||
2985 | /* Set signed and unsigned types of the precision of this mode for the | |
2986 | shifts below. */ | |
5826cacf RK |
2987 | signed_type = type_for_mode (nmode, 0); |
2988 | unsigned_type = type_for_mode (nmode, 1); | |
6d716ca8 | 2989 | |
6d716ca8 RS |
2990 | /* Compute the bit position and size for the new reference and our offset |
2991 | within it. If the new reference is the same size as the original, we | |
2992 | won't optimize anything, so return zero. */ | |
5826cacf RK |
2993 | nbitsize = GET_MODE_BITSIZE (nmode); |
2994 | nbitpos = lbitpos & ~ (nbitsize - 1); | |
2995 | lbitpos -= nbitpos; | |
2996 | if (nbitsize == lbitsize) | |
6d716ca8 RS |
2997 | return 0; |
2998 | ||
f76b9db2 | 2999 | if (BYTES_BIG_ENDIAN) |
5826cacf | 3000 | lbitpos = nbitsize - lbitsize - lbitpos; |
6d716ca8 RS |
3001 | |
3002 | /* Make the mask to be used against the extracted field. */ | |
13af526d RS |
3003 | mask = build_int_2 (~0, ~0); |
3004 | TREE_TYPE (mask) = unsigned_type; | |
aa830baf | 3005 | force_fit_type (mask, 0); |
13af526d | 3006 | mask = convert (unsigned_type, mask); |
5826cacf | 3007 | mask = const_binop (LSHIFT_EXPR, mask, size_int (nbitsize - lbitsize), 0); |
6d716ca8 | 3008 | mask = const_binop (RSHIFT_EXPR, mask, |
5826cacf | 3009 | size_int (nbitsize - lbitsize - lbitpos), 0); |
6d716ca8 RS |
3010 | |
3011 | if (! const_p) | |
3012 | /* If not comparing with constant, just rework the comparison | |
3013 | and return. */ | |
3014 | return build (code, compare_type, | |
c0b9d4c8 RK |
3015 | build (BIT_AND_EXPR, unsigned_type, |
3016 | make_bit_field_ref (linner, unsigned_type, | |
5826cacf | 3017 | nbitsize, nbitpos, 1), |
6d716ca8 | 3018 | mask), |
c0b9d4c8 RK |
3019 | build (BIT_AND_EXPR, unsigned_type, |
3020 | make_bit_field_ref (rinner, unsigned_type, | |
5826cacf | 3021 | nbitsize, nbitpos, 1), |
6d716ca8 RS |
3022 | mask)); |
3023 | ||
3024 | /* Otherwise, we are handling the constant case. See if the constant is too | |
3025 | big for the field. Warn and return a tree of for 0 (false) if so. We do | |
3026 | this not only for its own sake, but to avoid having to test for this | |
3027 | error case below. If we didn't, we might generate wrong code. | |
3028 | ||
3029 | For unsigned fields, the constant shifted right by the field length should | |
b6cc0a72 | 3030 | be all zero. For signed fields, the high-order bits should agree with |
6d716ca8 RS |
3031 | the sign bit. */ |
3032 | ||
3033 | if (lunsignedp) | |
3034 | { | |
3035 | if (! integer_zerop (const_binop (RSHIFT_EXPR, | |
3036 | convert (unsigned_type, rhs), | |
91d33e36 | 3037 | size_int (lbitsize), 0))) |
6d716ca8 | 3038 | { |
ab87f8c8 JL |
3039 | warning ("comparison is always %d due to width of bitfield", |
3040 | code == NE_EXPR); | |
6d716ca8 RS |
3041 | return convert (compare_type, |
3042 | (code == NE_EXPR | |
3043 | ? integer_one_node : integer_zero_node)); | |
3044 | } | |
3045 | } | |
3046 | else | |
3047 | { | |
3048 | tree tem = const_binop (RSHIFT_EXPR, convert (signed_type, rhs), | |
91d33e36 | 3049 | size_int (lbitsize - 1), 0); |
6d716ca8 RS |
3050 | if (! integer_zerop (tem) && ! integer_all_onesp (tem)) |
3051 | { | |
ab87f8c8 JL |
3052 | warning ("comparison is always %d due to width of bitfield", |
3053 | code == NE_EXPR); | |
6d716ca8 RS |
3054 | return convert (compare_type, |
3055 | (code == NE_EXPR | |
3056 | ? integer_one_node : integer_zero_node)); | |
3057 | } | |
3058 | } | |
3059 | ||
3060 | /* Single-bit compares should always be against zero. */ | |
3061 | if (lbitsize == 1 && ! integer_zerop (rhs)) | |
3062 | { | |
3063 | code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR; | |
3064 | rhs = convert (type, integer_zero_node); | |
3065 | } | |
3066 | ||
3067 | /* Make a new bitfield reference, shift the constant over the | |
3068 | appropriate number of bits and mask it with the computed mask | |
3069 | (in case this was a signed field). If we changed it, make a new one. */ | |
5826cacf | 3070 | lhs = make_bit_field_ref (linner, unsigned_type, nbitsize, nbitpos, 1); |
9db73acb RK |
3071 | if (lvolatilep) |
3072 | { | |
3073 | TREE_SIDE_EFFECTS (lhs) = 1; | |
3074 | TREE_THIS_VOLATILE (lhs) = 1; | |
3075 | } | |
6d716ca8 | 3076 | |
c0b9d4c8 RK |
3077 | rhs = fold (const_binop (BIT_AND_EXPR, |
3078 | const_binop (LSHIFT_EXPR, | |
3079 | convert (unsigned_type, rhs), | |
194c082f | 3080 | size_int (lbitpos), 0), |
91d33e36 | 3081 | mask, 0)); |
6d716ca8 RS |
3082 | |
3083 | return build (code, compare_type, | |
c0b9d4c8 | 3084 | build (BIT_AND_EXPR, unsigned_type, lhs, mask), |
6d716ca8 RS |
3085 | rhs); |
3086 | } | |
3087 | \f | |
b2215d83 | 3088 | /* Subroutine for fold_truthop: decode a field reference. |
6d716ca8 RS |
3089 | |
3090 | If EXP is a comparison reference, we return the innermost reference. | |
3091 | ||
3092 | *PBITSIZE is set to the number of bits in the reference, *PBITPOS is | |
3093 | set to the starting bit number. | |
3094 | ||
3095 | If the innermost field can be completely contained in a mode-sized | |
3096 | unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode. | |
3097 | ||
3098 | *PVOLATILEP is set to 1 if the any expression encountered is volatile; | |
3099 | otherwise it is not changed. | |
3100 | ||
3101 | *PUNSIGNEDP is set to the signedness of the field. | |
3102 | ||
3103 | *PMASK is set to the mask used. This is either contained in a | |
3104 | BIT_AND_EXPR or derived from the width of the field. | |
3105 | ||
38e01259 | 3106 | *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any. |
d4453ee5 | 3107 | |
6d716ca8 RS |
3108 | Return 0 if this is not a component reference or is one that we can't |
3109 | do anything with. */ | |
3110 | ||
3111 | static tree | |
3112 | decode_field_reference (exp, pbitsize, pbitpos, pmode, punsignedp, | |
d4453ee5 | 3113 | pvolatilep, pmask, pand_mask) |
6d716ca8 | 3114 | tree exp; |
770ae6cc | 3115 | HOST_WIDE_INT *pbitsize, *pbitpos; |
6d716ca8 RS |
3116 | enum machine_mode *pmode; |
3117 | int *punsignedp, *pvolatilep; | |
3118 | tree *pmask; | |
d4453ee5 | 3119 | tree *pand_mask; |
6d716ca8 | 3120 | { |
6d9f1f5f RK |
3121 | tree and_mask = 0; |
3122 | tree mask, inner, offset; | |
3123 | tree unsigned_type; | |
770ae6cc RK |
3124 | unsigned int precision; |
3125 | unsigned int alignment; | |
6d716ca8 | 3126 | |
b6cc0a72 | 3127 | /* All the optimizations using this function assume integer fields. |
772ae9f0 RK |
3128 | There are problems with FP fields since the type_for_size call |
3129 | below can fail for, e.g., XFmode. */ | |
3130 | if (! INTEGRAL_TYPE_P (TREE_TYPE (exp))) | |
3131 | return 0; | |
3132 | ||
6d716ca8 RS |
3133 | STRIP_NOPS (exp); |
3134 | ||
3135 | if (TREE_CODE (exp) == BIT_AND_EXPR) | |
3136 | { | |
6d9f1f5f | 3137 | and_mask = TREE_OPERAND (exp, 1); |
6d716ca8 | 3138 | exp = TREE_OPERAND (exp, 0); |
6d9f1f5f RK |
3139 | STRIP_NOPS (exp); STRIP_NOPS (and_mask); |
3140 | if (TREE_CODE (and_mask) != INTEGER_CST) | |
6d716ca8 RS |
3141 | return 0; |
3142 | } | |
3143 | ||
f1e60ec6 | 3144 | inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode, |
23bd99ae | 3145 | punsignedp, pvolatilep, &alignment); |
02103577 | 3146 | if ((inner == exp && and_mask == 0) |
14a774a9 RK |
3147 | || *pbitsize < 0 || offset != 0 |
3148 | || TREE_CODE (inner) == PLACEHOLDER_EXPR) | |
c05a9b68 | 3149 | return 0; |
b6cc0a72 | 3150 | |
6d9f1f5f RK |
3151 | /* Compute the mask to access the bitfield. */ |
3152 | unsigned_type = type_for_size (*pbitsize, 1); | |
3153 | precision = TYPE_PRECISION (unsigned_type); | |
3154 | ||
3155 | mask = build_int_2 (~0, ~0); | |
3156 | TREE_TYPE (mask) = unsigned_type; | |
3157 | force_fit_type (mask, 0); | |
3158 | mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0); | |
3159 | mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0); | |
3160 | ||
3161 | /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */ | |
3162 | if (and_mask != 0) | |
3163 | mask = fold (build (BIT_AND_EXPR, unsigned_type, | |
3164 | convert (unsigned_type, and_mask), mask)); | |
6d716ca8 RS |
3165 | |
3166 | *pmask = mask; | |
d4453ee5 | 3167 | *pand_mask = and_mask; |
6d716ca8 RS |
3168 | return inner; |
3169 | } | |
3170 | ||
6dc42e49 | 3171 | /* Return non-zero if MASK represents a mask of SIZE ones in the low-order |
6d716ca8 RS |
3172 | bit positions. */ |
3173 | ||
3174 | static int | |
3175 | all_ones_mask_p (mask, size) | |
3176 | tree mask; | |
3177 | int size; | |
3178 | { | |
3179 | tree type = TREE_TYPE (mask); | |
770ae6cc | 3180 | unsigned int precision = TYPE_PRECISION (type); |
13af526d | 3181 | tree tmask; |
6d716ca8 | 3182 | |
13af526d RS |
3183 | tmask = build_int_2 (~0, ~0); |
3184 | TREE_TYPE (tmask) = signed_type (type); | |
aa830baf | 3185 | force_fit_type (tmask, 0); |
6d716ca8 | 3186 | return |
b6cc0a72 | 3187 | tree_int_cst_equal (mask, |
02103577 RK |
3188 | const_binop (RSHIFT_EXPR, |
3189 | const_binop (LSHIFT_EXPR, tmask, | |
3190 | size_int (precision - size), | |
3191 | 0), | |
3192 | size_int (precision - size), 0)); | |
6d716ca8 | 3193 | } |
b2215d83 TW |
3194 | |
3195 | /* Subroutine for fold_truthop: determine if an operand is simple enough | |
3196 | to be evaluated unconditionally. */ | |
3197 | ||
b6cc0a72 | 3198 | static int |
b2215d83 TW |
3199 | simple_operand_p (exp) |
3200 | tree exp; | |
3201 | { | |
3202 | /* Strip any conversions that don't change the machine mode. */ | |
3203 | while ((TREE_CODE (exp) == NOP_EXPR | |
3204 | || TREE_CODE (exp) == CONVERT_EXPR) | |
3205 | && (TYPE_MODE (TREE_TYPE (exp)) | |
3206 | == TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))))) | |
3207 | exp = TREE_OPERAND (exp, 0); | |
3208 | ||
3209 | return (TREE_CODE_CLASS (TREE_CODE (exp)) == 'c' | |
2f939d94 | 3210 | || (DECL_P (exp) |
b2215d83 TW |
3211 | && ! TREE_ADDRESSABLE (exp) |
3212 | && ! TREE_THIS_VOLATILE (exp) | |
8227896c TW |
3213 | && ! DECL_NONLOCAL (exp) |
3214 | /* Don't regard global variables as simple. They may be | |
3215 | allocated in ways unknown to the compiler (shared memory, | |
3216 | #pragma weak, etc). */ | |
3217 | && ! TREE_PUBLIC (exp) | |
3218 | && ! DECL_EXTERNAL (exp) | |
3219 | /* Loading a static variable is unduly expensive, but global | |
3220 | registers aren't expensive. */ | |
3221 | && (! TREE_STATIC (exp) || DECL_REGISTER (exp)))); | |
b2215d83 | 3222 | } |
6d716ca8 | 3223 | \f |
ebde8a27 RK |
3224 | /* The following functions are subroutines to fold_range_test and allow it to |
3225 | try to change a logical combination of comparisons into a range test. | |
3226 | ||
3227 | For example, both | |
f42ef510 | 3228 | X == 2 || X == 3 || X == 4 || X == 5 |
ebde8a27 RK |
3229 | and |
3230 | X >= 2 && X <= 5 | |
3231 | are converted to | |
3232 | (unsigned) (X - 2) <= 3 | |
3233 | ||
956d6950 | 3234 | We describe each set of comparisons as being either inside or outside |
ebde8a27 RK |
3235 | a range, using a variable named like IN_P, and then describe the |
3236 | range with a lower and upper bound. If one of the bounds is omitted, | |
3237 | it represents either the highest or lowest value of the type. | |
3238 | ||
3239 | In the comments below, we represent a range by two numbers in brackets | |
956d6950 | 3240 | preceded by a "+" to designate being inside that range, or a "-" to |
ebde8a27 RK |
3241 | designate being outside that range, so the condition can be inverted by |
3242 | flipping the prefix. An omitted bound is represented by a "-". For | |
3243 | example, "- [-, 10]" means being outside the range starting at the lowest | |
3244 | possible value and ending at 10, in other words, being greater than 10. | |
3245 | The range "+ [-, -]" is always true and hence the range "- [-, -]" is | |
3246 | always false. | |
3247 | ||
3248 | We set up things so that the missing bounds are handled in a consistent | |
3249 | manner so neither a missing bound nor "true" and "false" need to be | |
3250 | handled using a special case. */ | |
3251 | ||
3252 | /* Return the result of applying CODE to ARG0 and ARG1, but handle the case | |
3253 | of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P | |
3254 | and UPPER1_P are nonzero if the respective argument is an upper bound | |
3255 | and zero for a lower. TYPE, if nonzero, is the type of the result; it | |
3256 | must be specified for a comparison. ARG1 will be converted to ARG0's | |
3257 | type if both are specified. */ | |
ef659ec0 | 3258 | |
ebde8a27 RK |
3259 | static tree |
3260 | range_binop (code, type, arg0, upper0_p, arg1, upper1_p) | |
3261 | enum tree_code code; | |
3262 | tree type; | |
3263 | tree arg0, arg1; | |
3264 | int upper0_p, upper1_p; | |
3265 | { | |
27bae8e5 | 3266 | tree tem; |
ebde8a27 RK |
3267 | int result; |
3268 | int sgn0, sgn1; | |
ef659ec0 | 3269 | |
ebde8a27 RK |
3270 | /* If neither arg represents infinity, do the normal operation. |
3271 | Else, if not a comparison, return infinity. Else handle the special | |
3272 | comparison rules. Note that most of the cases below won't occur, but | |
3273 | are handled for consistency. */ | |
ef659ec0 | 3274 | |
ebde8a27 | 3275 | if (arg0 != 0 && arg1 != 0) |
27bae8e5 RK |
3276 | { |
3277 | tem = fold (build (code, type != 0 ? type : TREE_TYPE (arg0), | |
3278 | arg0, convert (TREE_TYPE (arg0), arg1))); | |
3279 | STRIP_NOPS (tem); | |
3280 | return TREE_CODE (tem) == INTEGER_CST ? tem : 0; | |
3281 | } | |
ef659ec0 | 3282 | |
ebde8a27 RK |
3283 | if (TREE_CODE_CLASS (code) != '<') |
3284 | return 0; | |
3285 | ||
3286 | /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0 | |
d7b3ea38 NS |
3287 | for neither. In real maths, we cannot assume open ended ranges are |
3288 | the same. But, this is computer arithmetic, where numbers are finite. | |
3289 | We can therefore make the transformation of any unbounded range with | |
3290 | the value Z, Z being greater than any representable number. This permits | |
30f7a378 | 3291 | us to treat unbounded ranges as equal. */ |
ebde8a27 | 3292 | sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1); |
4e644c93 | 3293 | sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1); |
ebde8a27 RK |
3294 | switch (code) |
3295 | { | |
d7b3ea38 NS |
3296 | case EQ_EXPR: |
3297 | result = sgn0 == sgn1; | |
3298 | break; | |
3299 | case NE_EXPR: | |
3300 | result = sgn0 != sgn1; | |
ebde8a27 | 3301 | break; |
d7b3ea38 | 3302 | case LT_EXPR: |
ebde8a27 RK |
3303 | result = sgn0 < sgn1; |
3304 | break; | |
d7b3ea38 NS |
3305 | case LE_EXPR: |
3306 | result = sgn0 <= sgn1; | |
3307 | break; | |
3308 | case GT_EXPR: | |
ebde8a27 RK |
3309 | result = sgn0 > sgn1; |
3310 | break; | |
d7b3ea38 NS |
3311 | case GE_EXPR: |
3312 | result = sgn0 >= sgn1; | |
3313 | break; | |
e9a25f70 JL |
3314 | default: |
3315 | abort (); | |
ebde8a27 RK |
3316 | } |
3317 | ||
3318 | return convert (type, result ? integer_one_node : integer_zero_node); | |
3319 | } | |
b6cc0a72 | 3320 | \f |
ebde8a27 RK |
3321 | /* Given EXP, a logical expression, set the range it is testing into |
3322 | variables denoted by PIN_P, PLOW, and PHIGH. Return the expression | |
f42ef510 | 3323 | actually being tested. *PLOW and *PHIGH will be made of the same type |
ebde8a27 RK |
3324 | as the returned expression. If EXP is not a comparison, we will most |
3325 | likely not be returning a useful value and range. */ | |
ef659ec0 | 3326 | |
6dc7571d | 3327 | static tree |
ebde8a27 RK |
3328 | make_range (exp, pin_p, plow, phigh) |
3329 | tree exp; | |
3330 | int *pin_p; | |
3331 | tree *plow, *phigh; | |
ef659ec0 | 3332 | { |
ebde8a27 | 3333 | enum tree_code code; |
07444f1d | 3334 | tree arg0 = NULL_TREE, arg1 = NULL_TREE, type = NULL_TREE; |
7d12cee1 | 3335 | tree orig_type = NULL_TREE; |
ebde8a27 RK |
3336 | int in_p, n_in_p; |
3337 | tree low, high, n_low, n_high; | |
ef659ec0 | 3338 | |
ebde8a27 RK |
3339 | /* Start with simply saying "EXP != 0" and then look at the code of EXP |
3340 | and see if we can refine the range. Some of the cases below may not | |
3341 | happen, but it doesn't seem worth worrying about this. We "continue" | |
3342 | the outer loop when we've changed something; otherwise we "break" | |
3343 | the switch, which will "break" the while. */ | |
ef659ec0 | 3344 | |
ebde8a27 RK |
3345 | in_p = 0, low = high = convert (TREE_TYPE (exp), integer_zero_node); |
3346 | ||
3347 | while (1) | |
ef659ec0 | 3348 | { |
ebde8a27 | 3349 | code = TREE_CODE (exp); |
30d68b86 MM |
3350 | |
3351 | if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code))) | |
3352 | { | |
3353 | arg0 = TREE_OPERAND (exp, 0); | |
b6cc0a72 | 3354 | if (TREE_CODE_CLASS (code) == '<' |
30d68b86 MM |
3355 | || TREE_CODE_CLASS (code) == '1' |
3356 | || TREE_CODE_CLASS (code) == '2') | |
3357 | type = TREE_TYPE (arg0); | |
b6cc0a72 | 3358 | if (TREE_CODE_CLASS (code) == '2' |
30d68b86 | 3359 | || TREE_CODE_CLASS (code) == '<' |
b6cc0a72 | 3360 | || (TREE_CODE_CLASS (code) == 'e' |
efd58783 | 3361 | && TREE_CODE_LENGTH (code) > 1)) |
30d68b86 MM |
3362 | arg1 = TREE_OPERAND (exp, 1); |
3363 | } | |
ef659ec0 | 3364 | |
cc33944a RE |
3365 | /* Set ORIG_TYPE as soon as TYPE is non-null so that we do not |
3366 | lose a cast by accident. */ | |
3367 | if (type != NULL_TREE && orig_type == NULL_TREE) | |
3368 | orig_type = type; | |
3369 | ||
ebde8a27 RK |
3370 | switch (code) |
3371 | { | |
3372 | case TRUTH_NOT_EXPR: | |
3373 | in_p = ! in_p, exp = arg0; | |
3374 | continue; | |
3375 | ||
3376 | case EQ_EXPR: case NE_EXPR: | |
3377 | case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR: | |
3378 | /* We can only do something if the range is testing for zero | |
3379 | and if the second operand is an integer constant. Note that | |
3380 | saying something is "in" the range we make is done by | |
3381 | complementing IN_P since it will set in the initial case of | |
3382 | being not equal to zero; "out" is leaving it alone. */ | |
3383 | if (low == 0 || high == 0 | |
3384 | || ! integer_zerop (low) || ! integer_zerop (high) | |
3385 | || TREE_CODE (arg1) != INTEGER_CST) | |
3386 | break; | |
ef659ec0 | 3387 | |
ebde8a27 RK |
3388 | switch (code) |
3389 | { | |
3390 | case NE_EXPR: /* - [c, c] */ | |
3391 | low = high = arg1; | |
3392 | break; | |
3393 | case EQ_EXPR: /* + [c, c] */ | |
3394 | in_p = ! in_p, low = high = arg1; | |
3395 | break; | |
3396 | case GT_EXPR: /* - [-, c] */ | |
3397 | low = 0, high = arg1; | |
3398 | break; | |
3399 | case GE_EXPR: /* + [c, -] */ | |
3400 | in_p = ! in_p, low = arg1, high = 0; | |
3401 | break; | |
3402 | case LT_EXPR: /* - [c, -] */ | |
3403 | low = arg1, high = 0; | |
3404 | break; | |
3405 | case LE_EXPR: /* + [-, c] */ | |
3406 | in_p = ! in_p, low = 0, high = arg1; | |
3407 | break; | |
e9a25f70 JL |
3408 | default: |
3409 | abort (); | |
ebde8a27 | 3410 | } |
ef659ec0 | 3411 | |
ebde8a27 | 3412 | exp = arg0; |
ef659ec0 | 3413 | |
7f423031 | 3414 | /* If this is an unsigned comparison, we also know that EXP is |
0e1c7fc7 RK |
3415 | greater than or equal to zero. We base the range tests we make |
3416 | on that fact, so we record it here so we can parse existing | |
3417 | range tests. */ | |
7f423031 | 3418 | if (TREE_UNSIGNED (type) && (low == 0 || high == 0)) |
ebde8a27 RK |
3419 | { |
3420 | if (! merge_ranges (&n_in_p, &n_low, &n_high, in_p, low, high, | |
3421 | 1, convert (type, integer_zero_node), | |
0e1c7fc7 | 3422 | NULL_TREE)) |
ebde8a27 | 3423 | break; |
ef659ec0 | 3424 | |
ebde8a27 | 3425 | in_p = n_in_p, low = n_low, high = n_high; |
0e1c7fc7 | 3426 | |
c565a6b7 R |
3427 | /* If the high bound is missing, but we |
3428 | have a low bound, reverse the range so | |
3429 | it goes from zero to the low bound minus 1. */ | |
3430 | if (high == 0 && low) | |
0e1c7fc7 RK |
3431 | { |
3432 | in_p = ! in_p; | |
3433 | high = range_binop (MINUS_EXPR, NULL_TREE, low, 0, | |
3434 | integer_one_node, 0); | |
3435 | low = convert (type, integer_zero_node); | |
3436 | } | |
ebde8a27 RK |
3437 | } |
3438 | continue; | |
3439 | ||
3440 | case NEGATE_EXPR: | |
3441 | /* (-x) IN [a,b] -> x in [-b, -a] */ | |
3442 | n_low = range_binop (MINUS_EXPR, type, | |
3443 | convert (type, integer_zero_node), 0, high, 1); | |
3444 | n_high = range_binop (MINUS_EXPR, type, | |
3445 | convert (type, integer_zero_node), 0, low, 0); | |
3446 | low = n_low, high = n_high; | |
3447 | exp = arg0; | |
3448 | continue; | |
3449 | ||
3450 | case BIT_NOT_EXPR: | |
3451 | /* ~ X -> -X - 1 */ | |
1baa375f | 3452 | exp = build (MINUS_EXPR, type, negate_expr (arg0), |
27bae8e5 | 3453 | convert (type, integer_one_node)); |
ebde8a27 RK |
3454 | continue; |
3455 | ||
3456 | case PLUS_EXPR: case MINUS_EXPR: | |
3457 | if (TREE_CODE (arg1) != INTEGER_CST) | |
3458 | break; | |
3459 | ||
3460 | /* If EXP is signed, any overflow in the computation is undefined, | |
3461 | so we don't worry about it so long as our computations on | |
3462 | the bounds don't overflow. For unsigned, overflow is defined | |
3463 | and this is exactly the right thing. */ | |
3464 | n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR, | |
3465 | type, low, 0, arg1, 0); | |
3466 | n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR, | |
3467 | type, high, 1, arg1, 0); | |
3468 | if ((n_low != 0 && TREE_OVERFLOW (n_low)) | |
3469 | || (n_high != 0 && TREE_OVERFLOW (n_high))) | |
3470 | break; | |
3471 | ||
3c00684e JL |
3472 | /* Check for an unsigned range which has wrapped around the maximum |
3473 | value thus making n_high < n_low, and normalize it. */ | |
5a9d82a6 | 3474 | if (n_low && n_high && tree_int_cst_lt (n_high, n_low)) |
3c00684e JL |
3475 | { |
3476 | low = range_binop (PLUS_EXPR, type, n_high, 0, | |
0e1c7fc7 | 3477 | integer_one_node, 0); |
3c00684e | 3478 | high = range_binop (MINUS_EXPR, type, n_low, 0, |
c2b63960 AO |
3479 | integer_one_node, 0); |
3480 | ||
3481 | /* If the range is of the form +/- [ x+1, x ], we won't | |
3482 | be able to normalize it. But then, it represents the | |
3483 | whole range or the empty set, so make it | |
3484 | +/- [ -, - ]. */ | |
3485 | if (tree_int_cst_equal (n_low, low) | |
3486 | && tree_int_cst_equal (n_high, high)) | |
3487 | low = high = 0; | |
3488 | else | |
3489 | in_p = ! in_p; | |
3c00684e | 3490 | } |
5a9d82a6 JW |
3491 | else |
3492 | low = n_low, high = n_high; | |
27bae8e5 | 3493 | |
ebde8a27 RK |
3494 | exp = arg0; |
3495 | continue; | |
3496 | ||
3497 | case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR: | |
7d12cee1 JL |
3498 | if (TYPE_PRECISION (type) > TYPE_PRECISION (orig_type)) |
3499 | break; | |
3500 | ||
ebde8a27 RK |
3501 | if (! INTEGRAL_TYPE_P (type) |
3502 | || (low != 0 && ! int_fits_type_p (low, type)) | |
3503 | || (high != 0 && ! int_fits_type_p (high, type))) | |
3504 | break; | |
3505 | ||
ce2157a1 | 3506 | n_low = low, n_high = high; |
ebde8a27 | 3507 | |
ce2157a1 JL |
3508 | if (n_low != 0) |
3509 | n_low = convert (type, n_low); | |
3510 | ||
3511 | if (n_high != 0) | |
3512 | n_high = convert (type, n_high); | |
3513 | ||
3514 | /* If we're converting from an unsigned to a signed type, | |
3515 | we will be doing the comparison as unsigned. The tests above | |
3516 | have already verified that LOW and HIGH are both positive. | |
3517 | ||
3518 | So we have to make sure that the original unsigned value will | |
3519 | be interpreted as positive. */ | |
3520 | if (TREE_UNSIGNED (type) && ! TREE_UNSIGNED (TREE_TYPE (exp))) | |
3521 | { | |
3522 | tree equiv_type = type_for_mode (TYPE_MODE (type), 1); | |
e1ee5cdc RH |
3523 | tree high_positive; |
3524 | ||
3525 | /* A range without an upper bound is, naturally, unbounded. | |
3526 | Since convert would have cropped a very large value, use | |
14a774a9 RK |
3527 | the max value for the destination type. */ |
3528 | high_positive | |
3529 | = TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type) | |
3530 | : TYPE_MAX_VALUE (type); | |
e1ee5cdc | 3531 | |
e1ee5cdc RH |
3532 | high_positive = fold (build (RSHIFT_EXPR, type, |
3533 | convert (type, high_positive), | |
3534 | convert (type, integer_one_node))); | |
b6cc0a72 | 3535 | |
ce2157a1 JL |
3536 | /* If the low bound is specified, "and" the range with the |
3537 | range for which the original unsigned value will be | |
3538 | positive. */ | |
3539 | if (low != 0) | |
3540 | { | |
3541 | if (! merge_ranges (&n_in_p, &n_low, &n_high, | |
3542 | 1, n_low, n_high, | |
3543 | 1, convert (type, integer_zero_node), | |
3544 | high_positive)) | |
3545 | break; | |
3546 | ||
3547 | in_p = (n_in_p == in_p); | |
3548 | } | |
3549 | else | |
3550 | { | |
3551 | /* Otherwise, "or" the range with the range of the input | |
3552 | that will be interpreted as negative. */ | |
3553 | if (! merge_ranges (&n_in_p, &n_low, &n_high, | |
3554 | 0, n_low, n_high, | |
3555 | 1, convert (type, integer_zero_node), | |
3556 | high_positive)) | |
3557 | break; | |
3558 | ||
3559 | in_p = (in_p != n_in_p); | |
3560 | } | |
3561 | } | |
ebde8a27 RK |
3562 | |
3563 | exp = arg0; | |
ce2157a1 | 3564 | low = n_low, high = n_high; |
ebde8a27 | 3565 | continue; |
ce2157a1 JL |
3566 | |
3567 | default: | |
3568 | break; | |
ef659ec0 | 3569 | } |
ebde8a27 RK |
3570 | |
3571 | break; | |
ef659ec0 | 3572 | } |
ebde8a27 | 3573 | |
80906567 RK |
3574 | /* If EXP is a constant, we can evaluate whether this is true or false. */ |
3575 | if (TREE_CODE (exp) == INTEGER_CST) | |
3576 | { | |
3577 | in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node, | |
3578 | exp, 0, low, 0)) | |
3579 | && integer_onep (range_binop (LE_EXPR, integer_type_node, | |
3580 | exp, 1, high, 1))); | |
3581 | low = high = 0; | |
3582 | exp = 0; | |
3583 | } | |
3584 | ||
ebde8a27 RK |
3585 | *pin_p = in_p, *plow = low, *phigh = high; |
3586 | return exp; | |
3587 | } | |
3588 | \f | |
3589 | /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result | |
3590 | type, TYPE, return an expression to test if EXP is in (or out of, depending | |
3591 | on IN_P) the range. */ | |
3592 | ||
3593 | static tree | |
3594 | build_range_check (type, exp, in_p, low, high) | |
3595 | tree type; | |
3596 | tree exp; | |
3597 | int in_p; | |
3598 | tree low, high; | |
3599 | { | |
3600 | tree etype = TREE_TYPE (exp); | |
3601 | tree utype, value; | |
3602 | ||
3603 | if (! in_p | |
3604 | && (0 != (value = build_range_check (type, exp, 1, low, high)))) | |
3605 | return invert_truthvalue (value); | |
3606 | ||
3607 | else if (low == 0 && high == 0) | |
3608 | return convert (type, integer_one_node); | |
3609 | ||
3610 | else if (low == 0) | |
3611 | return fold (build (LE_EXPR, type, exp, high)); | |
3612 | ||
3613 | else if (high == 0) | |
3614 | return fold (build (GE_EXPR, type, exp, low)); | |
3615 | ||
3616 | else if (operand_equal_p (low, high, 0)) | |
3617 | return fold (build (EQ_EXPR, type, exp, low)); | |
3618 | ||
3619 | else if (TREE_UNSIGNED (etype) && integer_zerop (low)) | |
3620 | return build_range_check (type, exp, 1, 0, high); | |
3621 | ||
3622 | else if (integer_zerop (low)) | |
ef659ec0 | 3623 | { |
ebde8a27 RK |
3624 | utype = unsigned_type (etype); |
3625 | return build_range_check (type, convert (utype, exp), 1, 0, | |
3626 | convert (utype, high)); | |
3627 | } | |
ef659ec0 | 3628 | |
ebde8a27 RK |
3629 | else if (0 != (value = const_binop (MINUS_EXPR, high, low, 0)) |
3630 | && ! TREE_OVERFLOW (value)) | |
3631 | return build_range_check (type, | |
3632 | fold (build (MINUS_EXPR, etype, exp, low)), | |
3633 | 1, convert (etype, integer_zero_node), value); | |
3634 | else | |
3635 | return 0; | |
3636 | } | |
3637 | \f | |
b6cc0a72 | 3638 | /* Given two ranges, see if we can merge them into one. Return 1 if we |
ebde8a27 | 3639 | can, 0 if we can't. Set the output range into the specified parameters. */ |
ef659ec0 | 3640 | |
ebde8a27 RK |
3641 | static int |
3642 | merge_ranges (pin_p, plow, phigh, in0_p, low0, high0, in1_p, low1, high1) | |
3643 | int *pin_p; | |
3644 | tree *plow, *phigh; | |
3645 | int in0_p, in1_p; | |
3646 | tree low0, high0, low1, high1; | |
3647 | { | |
3648 | int no_overlap; | |
3649 | int subset; | |
3650 | int temp; | |
3651 | tree tem; | |
3652 | int in_p; | |
3653 | tree low, high; | |
ce2157a1 JL |
3654 | int lowequal = ((low0 == 0 && low1 == 0) |
3655 | || integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3656 | low0, 0, low1, 0))); | |
3657 | int highequal = ((high0 == 0 && high1 == 0) | |
3658 | || integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3659 | high0, 1, high1, 1))); | |
3660 | ||
3661 | /* Make range 0 be the range that starts first, or ends last if they | |
3662 | start at the same value. Swap them if it isn't. */ | |
b6cc0a72 | 3663 | if (integer_onep (range_binop (GT_EXPR, integer_type_node, |
ebde8a27 | 3664 | low0, 0, low1, 0)) |
ce2157a1 | 3665 | || (lowequal |
ebde8a27 | 3666 | && integer_onep (range_binop (GT_EXPR, integer_type_node, |
ce2157a1 | 3667 | high1, 1, high0, 1)))) |
ebde8a27 RK |
3668 | { |
3669 | temp = in0_p, in0_p = in1_p, in1_p = temp; | |
3670 | tem = low0, low0 = low1, low1 = tem; | |
3671 | tem = high0, high0 = high1, high1 = tem; | |
3672 | } | |
ef659ec0 | 3673 | |
ebde8a27 RK |
3674 | /* Now flag two cases, whether the ranges are disjoint or whether the |
3675 | second range is totally subsumed in the first. Note that the tests | |
3676 | below are simplified by the ones above. */ | |
3677 | no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node, | |
3678 | high0, 1, low1, 0)); | |
5df8a1f2 | 3679 | subset = integer_onep (range_binop (LE_EXPR, integer_type_node, |
ebde8a27 RK |
3680 | high1, 1, high0, 1)); |
3681 | ||
3682 | /* We now have four cases, depending on whether we are including or | |
3683 | excluding the two ranges. */ | |
3684 | if (in0_p && in1_p) | |
3685 | { | |
3686 | /* If they don't overlap, the result is false. If the second range | |
3687 | is a subset it is the result. Otherwise, the range is from the start | |
3688 | of the second to the end of the first. */ | |
3689 | if (no_overlap) | |
3690 | in_p = 0, low = high = 0; | |
3691 | else if (subset) | |
3692 | in_p = 1, low = low1, high = high1; | |
3693 | else | |
3694 | in_p = 1, low = low1, high = high0; | |
3695 | } | |
ef659ec0 | 3696 | |
ebde8a27 RK |
3697 | else if (in0_p && ! in1_p) |
3698 | { | |
ce2157a1 JL |
3699 | /* If they don't overlap, the result is the first range. If they are |
3700 | equal, the result is false. If the second range is a subset of the | |
3701 | first, and the ranges begin at the same place, we go from just after | |
3702 | the end of the first range to the end of the second. If the second | |
3703 | range is not a subset of the first, or if it is a subset and both | |
3704 | ranges end at the same place, the range starts at the start of the | |
3705 | first range and ends just before the second range. | |
3706 | Otherwise, we can't describe this as a single range. */ | |
ebde8a27 RK |
3707 | if (no_overlap) |
3708 | in_p = 1, low = low0, high = high0; | |
ce2157a1 | 3709 | else if (lowequal && highequal) |
405862dd | 3710 | in_p = 0, low = high = 0; |
ce2157a1 JL |
3711 | else if (subset && lowequal) |
3712 | { | |
3713 | in_p = 1, high = high0; | |
3714 | low = range_binop (PLUS_EXPR, NULL_TREE, high1, 0, | |
b6cc0a72 | 3715 | integer_one_node, 0); |
ce2157a1 JL |
3716 | } |
3717 | else if (! subset || highequal) | |
ebde8a27 RK |
3718 | { |
3719 | in_p = 1, low = low0; | |
3720 | high = range_binop (MINUS_EXPR, NULL_TREE, low1, 0, | |
0e1c7fc7 | 3721 | integer_one_node, 0); |
ebde8a27 | 3722 | } |
ce2157a1 JL |
3723 | else |
3724 | return 0; | |
ebde8a27 | 3725 | } |
ef659ec0 | 3726 | |
ebde8a27 RK |
3727 | else if (! in0_p && in1_p) |
3728 | { | |
3729 | /* If they don't overlap, the result is the second range. If the second | |
3730 | is a subset of the first, the result is false. Otherwise, | |
3731 | the range starts just after the first range and ends at the | |
3732 | end of the second. */ | |
3733 | if (no_overlap) | |
3734 | in_p = 1, low = low1, high = high1; | |
14a774a9 | 3735 | else if (subset || highequal) |
ebde8a27 RK |
3736 | in_p = 0, low = high = 0; |
3737 | else | |
3738 | { | |
3739 | in_p = 1, high = high1; | |
3740 | low = range_binop (PLUS_EXPR, NULL_TREE, high0, 1, | |
3741 | integer_one_node, 0); | |
ef659ec0 TW |
3742 | } |
3743 | } | |
3744 | ||
ebde8a27 RK |
3745 | else |
3746 | { | |
3747 | /* The case where we are excluding both ranges. Here the complex case | |
3748 | is if they don't overlap. In that case, the only time we have a | |
3749 | range is if they are adjacent. If the second is a subset of the | |
3750 | first, the result is the first. Otherwise, the range to exclude | |
3751 | starts at the beginning of the first range and ends at the end of the | |
3752 | second. */ | |
3753 | if (no_overlap) | |
3754 | { | |
3755 | if (integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3756 | range_binop (PLUS_EXPR, NULL_TREE, | |
3757 | high0, 1, | |
3758 | integer_one_node, 1), | |
3759 | 1, low1, 0))) | |
3760 | in_p = 0, low = low0, high = high1; | |
3761 | else | |
3762 | return 0; | |
3763 | } | |
3764 | else if (subset) | |
3765 | in_p = 0, low = low0, high = high0; | |
3766 | else | |
3767 | in_p = 0, low = low0, high = high1; | |
3768 | } | |
f5902869 | 3769 | |
ebde8a27 RK |
3770 | *pin_p = in_p, *plow = low, *phigh = high; |
3771 | return 1; | |
3772 | } | |
3773 | \f | |
3774 | /* EXP is some logical combination of boolean tests. See if we can | |
3775 | merge it into some range test. Return the new tree if so. */ | |
ef659ec0 | 3776 | |
ebde8a27 RK |
3777 | static tree |
3778 | fold_range_test (exp) | |
3779 | tree exp; | |
3780 | { | |
3781 | int or_op = (TREE_CODE (exp) == TRUTH_ORIF_EXPR | |
3782 | || TREE_CODE (exp) == TRUTH_OR_EXPR); | |
3783 | int in0_p, in1_p, in_p; | |
3784 | tree low0, low1, low, high0, high1, high; | |
3785 | tree lhs = make_range (TREE_OPERAND (exp, 0), &in0_p, &low0, &high0); | |
3786 | tree rhs = make_range (TREE_OPERAND (exp, 1), &in1_p, &low1, &high1); | |
3787 | tree tem; | |
ef659ec0 | 3788 | |
ebde8a27 RK |
3789 | /* If this is an OR operation, invert both sides; we will invert |
3790 | again at the end. */ | |
3791 | if (or_op) | |
3792 | in0_p = ! in0_p, in1_p = ! in1_p; | |
3793 | ||
3794 | /* If both expressions are the same, if we can merge the ranges, and we | |
80906567 RK |
3795 | can build the range test, return it or it inverted. If one of the |
3796 | ranges is always true or always false, consider it to be the same | |
3797 | expression as the other. */ | |
3798 | if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0)) | |
ebde8a27 RK |
3799 | && merge_ranges (&in_p, &low, &high, in0_p, low0, high0, |
3800 | in1_p, low1, high1) | |
80906567 RK |
3801 | && 0 != (tem = (build_range_check (TREE_TYPE (exp), |
3802 | lhs != 0 ? lhs | |
3803 | : rhs != 0 ? rhs : integer_zero_node, | |
ebde8a27 RK |
3804 | in_p, low, high)))) |
3805 | return or_op ? invert_truthvalue (tem) : tem; | |
3806 | ||
3807 | /* On machines where the branch cost is expensive, if this is a | |
3808 | short-circuited branch and the underlying object on both sides | |
3809 | is the same, make a non-short-circuit operation. */ | |
3810 | else if (BRANCH_COST >= 2 | |
7cf5c9e1 | 3811 | && lhs != 0 && rhs != 0 |
ebde8a27 RK |
3812 | && (TREE_CODE (exp) == TRUTH_ANDIF_EXPR |
3813 | || TREE_CODE (exp) == TRUTH_ORIF_EXPR) | |
3814 | && operand_equal_p (lhs, rhs, 0)) | |
ef659ec0 | 3815 | { |
f0eebf28 | 3816 | /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR |
9ec36da5 JL |
3817 | unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in |
3818 | which cases we can't do this. */ | |
ebde8a27 RK |
3819 | if (simple_operand_p (lhs)) |
3820 | return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3821 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR, | |
3822 | TREE_TYPE (exp), TREE_OPERAND (exp, 0), | |
3823 | TREE_OPERAND (exp, 1)); | |
f0eebf28 | 3824 | |
c5c76735 | 3825 | else if (global_bindings_p () == 0 |
9ec36da5 | 3826 | && ! contains_placeholder_p (lhs)) |
ebde8a27 RK |
3827 | { |
3828 | tree common = save_expr (lhs); | |
3829 | ||
3830 | if (0 != (lhs = build_range_check (TREE_TYPE (exp), common, | |
3831 | or_op ? ! in0_p : in0_p, | |
3832 | low0, high0)) | |
3833 | && (0 != (rhs = build_range_check (TREE_TYPE (exp), common, | |
3834 | or_op ? ! in1_p : in1_p, | |
3835 | low1, high1)))) | |
3836 | return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3837 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR, | |
3838 | TREE_TYPE (exp), lhs, rhs); | |
3839 | } | |
ef659ec0 | 3840 | } |
de153e82 | 3841 | |
de153e82 | 3842 | return 0; |
ef659ec0 TW |
3843 | } |
3844 | \f | |
02103577 | 3845 | /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P |
25216284 | 3846 | bit value. Arrange things so the extra bits will be set to zero if and |
d4453ee5 RK |
3847 | only if C is signed-extended to its full width. If MASK is nonzero, |
3848 | it is an INTEGER_CST that should be AND'ed with the extra bits. */ | |
02103577 RK |
3849 | |
3850 | static tree | |
d4453ee5 | 3851 | unextend (c, p, unsignedp, mask) |
02103577 RK |
3852 | tree c; |
3853 | int p; | |
3854 | int unsignedp; | |
d4453ee5 | 3855 | tree mask; |
02103577 RK |
3856 | { |
3857 | tree type = TREE_TYPE (c); | |
3858 | int modesize = GET_MODE_BITSIZE (TYPE_MODE (type)); | |
3859 | tree temp; | |
3860 | ||
3861 | if (p == modesize || unsignedp) | |
3862 | return c; | |
3863 | ||
02103577 | 3864 | /* We work by getting just the sign bit into the low-order bit, then |
9faa82d8 | 3865 | into the high-order bit, then sign-extend. We then XOR that value |
02103577 RK |
3866 | with C. */ |
3867 | temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1), 0); | |
3868 | temp = const_binop (BIT_AND_EXPR, temp, size_int (1), 0); | |
cf85c69b JW |
3869 | |
3870 | /* We must use a signed type in order to get an arithmetic right shift. | |
3871 | However, we must also avoid introducing accidental overflows, so that | |
b6cc0a72 | 3872 | a subsequent call to integer_zerop will work. Hence we must |
cf85c69b JW |
3873 | do the type conversion here. At this point, the constant is either |
3874 | zero or one, and the conversion to a signed type can never overflow. | |
3875 | We could get an overflow if this conversion is done anywhere else. */ | |
3876 | if (TREE_UNSIGNED (type)) | |
3877 | temp = convert (signed_type (type), temp); | |
3878 | ||
02103577 RK |
3879 | temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0); |
3880 | temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0); | |
d4453ee5 RK |
3881 | if (mask != 0) |
3882 | temp = const_binop (BIT_AND_EXPR, temp, convert (TREE_TYPE (c), mask), 0); | |
cf85c69b JW |
3883 | /* If necessary, convert the type back to match the type of C. */ |
3884 | if (TREE_UNSIGNED (type)) | |
3885 | temp = convert (type, temp); | |
d4453ee5 | 3886 | |
02103577 RK |
3887 | return convert (type, const_binop (BIT_XOR_EXPR, c, temp, 0)); |
3888 | } | |
3889 | \f | |
b2215d83 TW |
3890 | /* Find ways of folding logical expressions of LHS and RHS: |
3891 | Try to merge two comparisons to the same innermost item. | |
3892 | Look for range tests like "ch >= '0' && ch <= '9'". | |
3893 | Look for combinations of simple terms on machines with expensive branches | |
3894 | and evaluate the RHS unconditionally. | |
6d716ca8 RS |
3895 | |
3896 | For example, if we have p->a == 2 && p->b == 4 and we can make an | |
3897 | object large enough to span both A and B, we can do this with a comparison | |
3898 | against the object ANDed with the a mask. | |
3899 | ||
3900 | If we have p->a == q->a && p->b == q->b, we may be able to use bit masking | |
3901 | operations to do this with one comparison. | |
3902 | ||
3903 | We check for both normal comparisons and the BIT_AND_EXPRs made this by | |
3904 | function and the one above. | |
3905 | ||
3906 | CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR, | |
3907 | TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR. | |
3908 | ||
3909 | TRUTH_TYPE is the type of the logical operand and LHS and RHS are its | |
3910 | two operands. | |
3911 | ||
3912 | We return the simplified tree or 0 if no optimization is possible. */ | |
3913 | ||
3914 | static tree | |
b2215d83 | 3915 | fold_truthop (code, truth_type, lhs, rhs) |
6d716ca8 RS |
3916 | enum tree_code code; |
3917 | tree truth_type, lhs, rhs; | |
3918 | { | |
f42ef510 | 3919 | /* If this is the "or" of two comparisons, we can do something if |
6d716ca8 | 3920 | the comparisons are NE_EXPR. If this is the "and", we can do something |
b6cc0a72 | 3921 | if the comparisons are EQ_EXPR. I.e., |
6d716ca8 RS |
3922 | (a->b == 2 && a->c == 4) can become (a->new == NEW). |
3923 | ||
3924 | WANTED_CODE is this operation code. For single bit fields, we can | |
3925 | convert EQ_EXPR to NE_EXPR so we need not reject the "wrong" | |
3926 | comparison for one-bit fields. */ | |
3927 | ||
b2215d83 | 3928 | enum tree_code wanted_code; |
6d716ca8 | 3929 | enum tree_code lcode, rcode; |
b2215d83 | 3930 | tree ll_arg, lr_arg, rl_arg, rr_arg; |
6d716ca8 | 3931 | tree ll_inner, lr_inner, rl_inner, rr_inner; |
770ae6cc RK |
3932 | HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos; |
3933 | HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos; | |
3934 | HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos; | |
3935 | HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos; | |
6d716ca8 RS |
3936 | int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp; |
3937 | enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode; | |
3938 | enum machine_mode lnmode, rnmode; | |
3939 | tree ll_mask, lr_mask, rl_mask, rr_mask; | |
d4453ee5 | 3940 | tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask; |
b2215d83 | 3941 | tree l_const, r_const; |
bd910dcf | 3942 | tree lntype, rntype, result; |
6d716ca8 | 3943 | int first_bit, end_bit; |
b2215d83 | 3944 | int volatilep; |
6d716ca8 | 3945 | |
ebde8a27 RK |
3946 | /* Start by getting the comparison codes. Fail if anything is volatile. |
3947 | If one operand is a BIT_AND_EXPR with the constant one, treat it as if | |
3948 | it were surrounded with a NE_EXPR. */ | |
6d716ca8 | 3949 | |
ebde8a27 | 3950 | if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs)) |
b2215d83 TW |
3951 | return 0; |
3952 | ||
6d716ca8 RS |
3953 | lcode = TREE_CODE (lhs); |
3954 | rcode = TREE_CODE (rhs); | |
ef659ec0 | 3955 | |
96d4cf0a RK |
3956 | if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1))) |
3957 | lcode = NE_EXPR, lhs = build (NE_EXPR, truth_type, lhs, integer_zero_node); | |
3958 | ||
3959 | if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1))) | |
3960 | rcode = NE_EXPR, rhs = build (NE_EXPR, truth_type, rhs, integer_zero_node); | |
3961 | ||
ebde8a27 | 3962 | if (TREE_CODE_CLASS (lcode) != '<' || TREE_CODE_CLASS (rcode) != '<') |
ef659ec0 TW |
3963 | return 0; |
3964 | ||
b2215d83 | 3965 | code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR) |
9c0ae98b | 3966 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR); |
b2215d83 TW |
3967 | |
3968 | ll_arg = TREE_OPERAND (lhs, 0); | |
3969 | lr_arg = TREE_OPERAND (lhs, 1); | |
3970 | rl_arg = TREE_OPERAND (rhs, 0); | |
3971 | rr_arg = TREE_OPERAND (rhs, 1); | |
b6cc0a72 | 3972 | |
8227896c | 3973 | /* If the RHS can be evaluated unconditionally and its operands are |
b2215d83 TW |
3974 | simple, it wins to evaluate the RHS unconditionally on machines |
3975 | with expensive branches. In this case, this isn't a comparison | |
1d691c53 RK |
3976 | that can be merged. Avoid doing this if the RHS is a floating-point |
3977 | comparison since those can trap. */ | |
b2215d83 TW |
3978 | |
3979 | if (BRANCH_COST >= 2 | |
1d691c53 | 3980 | && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg)) |
b2215d83 | 3981 | && simple_operand_p (rl_arg) |
8227896c | 3982 | && simple_operand_p (rr_arg)) |
b2215d83 TW |
3983 | return build (code, truth_type, lhs, rhs); |
3984 | ||
ef659ec0 TW |
3985 | /* See if the comparisons can be merged. Then get all the parameters for |
3986 | each side. */ | |
3987 | ||
6d716ca8 | 3988 | if ((lcode != EQ_EXPR && lcode != NE_EXPR) |
ef659ec0 | 3989 | || (rcode != EQ_EXPR && rcode != NE_EXPR)) |
6d716ca8 RS |
3990 | return 0; |
3991 | ||
b2215d83 TW |
3992 | volatilep = 0; |
3993 | ll_inner = decode_field_reference (ll_arg, | |
6d716ca8 | 3994 | &ll_bitsize, &ll_bitpos, &ll_mode, |
d4453ee5 RK |
3995 | &ll_unsignedp, &volatilep, &ll_mask, |
3996 | &ll_and_mask); | |
b2215d83 | 3997 | lr_inner = decode_field_reference (lr_arg, |
6d716ca8 | 3998 | &lr_bitsize, &lr_bitpos, &lr_mode, |
d4453ee5 RK |
3999 | &lr_unsignedp, &volatilep, &lr_mask, |
4000 | &lr_and_mask); | |
b2215d83 | 4001 | rl_inner = decode_field_reference (rl_arg, |
6d716ca8 | 4002 | &rl_bitsize, &rl_bitpos, &rl_mode, |
d4453ee5 RK |
4003 | &rl_unsignedp, &volatilep, &rl_mask, |
4004 | &rl_and_mask); | |
b2215d83 | 4005 | rr_inner = decode_field_reference (rr_arg, |
6d716ca8 | 4006 | &rr_bitsize, &rr_bitpos, &rr_mode, |
d4453ee5 RK |
4007 | &rr_unsignedp, &volatilep, &rr_mask, |
4008 | &rr_and_mask); | |
6d716ca8 RS |
4009 | |
4010 | /* It must be true that the inner operation on the lhs of each | |
4011 | comparison must be the same if we are to be able to do anything. | |
4012 | Then see if we have constants. If not, the same must be true for | |
4013 | the rhs's. */ | |
4014 | if (volatilep || ll_inner == 0 || rl_inner == 0 | |
4015 | || ! operand_equal_p (ll_inner, rl_inner, 0)) | |
4016 | return 0; | |
4017 | ||
b2215d83 TW |
4018 | if (TREE_CODE (lr_arg) == INTEGER_CST |
4019 | && TREE_CODE (rr_arg) == INTEGER_CST) | |
4020 | l_const = lr_arg, r_const = rr_arg; | |
6d716ca8 RS |
4021 | else if (lr_inner == 0 || rr_inner == 0 |
4022 | || ! operand_equal_p (lr_inner, rr_inner, 0)) | |
4023 | return 0; | |
b2215d83 TW |
4024 | else |
4025 | l_const = r_const = 0; | |
6d716ca8 RS |
4026 | |
4027 | /* If either comparison code is not correct for our logical operation, | |
4028 | fail. However, we can convert a one-bit comparison against zero into | |
4029 | the opposite comparison against that bit being set in the field. */ | |
b2215d83 | 4030 | |
9c0ae98b | 4031 | wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR); |
6d716ca8 RS |
4032 | if (lcode != wanted_code) |
4033 | { | |
4034 | if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask)) | |
5a6b3365 | 4035 | { |
2bd21a02 AS |
4036 | /* Make the left operand unsigned, since we are only interested |
4037 | in the value of one bit. Otherwise we are doing the wrong | |
4038 | thing below. */ | |
4039 | ll_unsignedp = 1; | |
71a874cd | 4040 | l_const = ll_mask; |
5a6b3365 | 4041 | } |
6d716ca8 RS |
4042 | else |
4043 | return 0; | |
4044 | } | |
4045 | ||
71a874cd | 4046 | /* This is analogous to the code for l_const above. */ |
6d716ca8 RS |
4047 | if (rcode != wanted_code) |
4048 | { | |
4049 | if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask)) | |
5a6b3365 | 4050 | { |
2bd21a02 | 4051 | rl_unsignedp = 1; |
71a874cd | 4052 | r_const = rl_mask; |
5a6b3365 | 4053 | } |
6d716ca8 RS |
4054 | else |
4055 | return 0; | |
4056 | } | |
4057 | ||
4058 | /* See if we can find a mode that contains both fields being compared on | |
4059 | the left. If we can't, fail. Otherwise, update all constants and masks | |
4060 | to be relative to a field of that size. */ | |
4061 | first_bit = MIN (ll_bitpos, rl_bitpos); | |
4062 | end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize); | |
4063 | lnmode = get_best_mode (end_bit - first_bit, first_bit, | |
4064 | TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode, | |
4065 | volatilep); | |
4066 | if (lnmode == VOIDmode) | |
4067 | return 0; | |
4068 | ||
4069 | lnbitsize = GET_MODE_BITSIZE (lnmode); | |
4070 | lnbitpos = first_bit & ~ (lnbitsize - 1); | |
bd910dcf | 4071 | lntype = type_for_size (lnbitsize, 1); |
6d716ca8 RS |
4072 | xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos; |
4073 | ||
f76b9db2 ILT |
4074 | if (BYTES_BIG_ENDIAN) |
4075 | { | |
4076 | xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize; | |
4077 | xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize; | |
4078 | } | |
6d716ca8 | 4079 | |
bd910dcf | 4080 | ll_mask = const_binop (LSHIFT_EXPR, convert (lntype, ll_mask), |
91d33e36 | 4081 | size_int (xll_bitpos), 0); |
bd910dcf | 4082 | rl_mask = const_binop (LSHIFT_EXPR, convert (lntype, rl_mask), |
91d33e36 | 4083 | size_int (xrl_bitpos), 0); |
6d716ca8 | 4084 | |
6d716ca8 RS |
4085 | if (l_const) |
4086 | { | |
bd910dcf | 4087 | l_const = convert (lntype, l_const); |
b6cc0a72 | 4088 | l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask); |
02103577 RK |
4089 | l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos), 0); |
4090 | if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const, | |
4091 | fold (build1 (BIT_NOT_EXPR, | |
bd910dcf | 4092 | lntype, ll_mask)), |
02103577 RK |
4093 | 0))) |
4094 | { | |
ab87f8c8 | 4095 | warning ("comparison is always %d", wanted_code == NE_EXPR); |
b6cc0a72 | 4096 | |
02103577 RK |
4097 | return convert (truth_type, |
4098 | wanted_code == NE_EXPR | |
4099 | ? integer_one_node : integer_zero_node); | |
4100 | } | |
6d716ca8 RS |
4101 | } |
4102 | if (r_const) | |
4103 | { | |
bd910dcf | 4104 | r_const = convert (lntype, r_const); |
d4453ee5 | 4105 | r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask); |
02103577 RK |
4106 | r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos), 0); |
4107 | if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const, | |
4108 | fold (build1 (BIT_NOT_EXPR, | |
bd910dcf | 4109 | lntype, rl_mask)), |
02103577 RK |
4110 | 0))) |
4111 | { | |
ab87f8c8 JL |
4112 | warning ("comparison is always %d", wanted_code == NE_EXPR); |
4113 | ||
02103577 RK |
4114 | return convert (truth_type, |
4115 | wanted_code == NE_EXPR | |
4116 | ? integer_one_node : integer_zero_node); | |
4117 | } | |
6d716ca8 RS |
4118 | } |
4119 | ||
4120 | /* If the right sides are not constant, do the same for it. Also, | |
4121 | disallow this optimization if a size or signedness mismatch occurs | |
4122 | between the left and right sides. */ | |
4123 | if (l_const == 0) | |
4124 | { | |
4125 | if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize | |
e6a28f26 RS |
4126 | || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp |
4127 | /* Make sure the two fields on the right | |
4128 | correspond to the left without being swapped. */ | |
4129 | || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos) | |
6d716ca8 RS |
4130 | return 0; |
4131 | ||
4132 | first_bit = MIN (lr_bitpos, rr_bitpos); | |
4133 | end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize); | |
4134 | rnmode = get_best_mode (end_bit - first_bit, first_bit, | |
4135 | TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode, | |
4136 | volatilep); | |
4137 | if (rnmode == VOIDmode) | |
4138 | return 0; | |
4139 | ||
4140 | rnbitsize = GET_MODE_BITSIZE (rnmode); | |
4141 | rnbitpos = first_bit & ~ (rnbitsize - 1); | |
bd910dcf | 4142 | rntype = type_for_size (rnbitsize, 1); |
6d716ca8 RS |
4143 | xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos; |
4144 | ||
f76b9db2 ILT |
4145 | if (BYTES_BIG_ENDIAN) |
4146 | { | |
4147 | xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize; | |
4148 | xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize; | |
4149 | } | |
6d716ca8 | 4150 | |
bd910dcf | 4151 | lr_mask = const_binop (LSHIFT_EXPR, convert (rntype, lr_mask), |
91d33e36 | 4152 | size_int (xlr_bitpos), 0); |
bd910dcf | 4153 | rr_mask = const_binop (LSHIFT_EXPR, convert (rntype, rr_mask), |
91d33e36 | 4154 | size_int (xrr_bitpos), 0); |
6d716ca8 RS |
4155 | |
4156 | /* Make a mask that corresponds to both fields being compared. | |
11a86c56 CH |
4157 | Do this for both items being compared. If the operands are the |
4158 | same size and the bits being compared are in the same position | |
4159 | then we can do this by masking both and comparing the masked | |
4160 | results. */ | |
91d33e36 RS |
4161 | ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0); |
4162 | lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask, 0); | |
11a86c56 | 4163 | if (lnbitsize == rnbitsize && xll_bitpos == xlr_bitpos) |
6d716ca8 | 4164 | { |
bd910dcf | 4165 | lhs = make_bit_field_ref (ll_inner, lntype, lnbitsize, lnbitpos, |
6d716ca8 | 4166 | ll_unsignedp || rl_unsignedp); |
11a86c56 CH |
4167 | if (! all_ones_mask_p (ll_mask, lnbitsize)) |
4168 | lhs = build (BIT_AND_EXPR, lntype, lhs, ll_mask); | |
4169 | ||
bd910dcf | 4170 | rhs = make_bit_field_ref (lr_inner, rntype, rnbitsize, rnbitpos, |
6d716ca8 | 4171 | lr_unsignedp || rr_unsignedp); |
11a86c56 CH |
4172 | if (! all_ones_mask_p (lr_mask, rnbitsize)) |
4173 | rhs = build (BIT_AND_EXPR, rntype, rhs, lr_mask); | |
4174 | ||
6d716ca8 RS |
4175 | return build (wanted_code, truth_type, lhs, rhs); |
4176 | } | |
4177 | ||
4178 | /* There is still another way we can do something: If both pairs of | |
4179 | fields being compared are adjacent, we may be able to make a wider | |
97ea7176 CH |
4180 | field containing them both. |
4181 | ||
4182 | Note that we still must mask the lhs/rhs expressions. Furthermore, | |
b6cc0a72 | 4183 | the mask must be shifted to account for the shift done by |
97ea7176 | 4184 | make_bit_field_ref. */ |
6d716ca8 RS |
4185 | if ((ll_bitsize + ll_bitpos == rl_bitpos |
4186 | && lr_bitsize + lr_bitpos == rr_bitpos) | |
4187 | || (ll_bitpos == rl_bitpos + rl_bitsize | |
4188 | && lr_bitpos == rr_bitpos + rr_bitsize)) | |
97ea7176 | 4189 | { |
bd910dcf CH |
4190 | tree type; |
4191 | ||
4192 | lhs = make_bit_field_ref (ll_inner, lntype, ll_bitsize + rl_bitsize, | |
97ea7176 | 4193 | MIN (ll_bitpos, rl_bitpos), ll_unsignedp); |
bd910dcf CH |
4194 | rhs = make_bit_field_ref (lr_inner, rntype, lr_bitsize + rr_bitsize, |
4195 | MIN (lr_bitpos, rr_bitpos), lr_unsignedp); | |
4196 | ||
97ea7176 CH |
4197 | ll_mask = const_binop (RSHIFT_EXPR, ll_mask, |
4198 | size_int (MIN (xll_bitpos, xrl_bitpos)), 0); | |
bd910dcf CH |
4199 | lr_mask = const_binop (RSHIFT_EXPR, lr_mask, |
4200 | size_int (MIN (xlr_bitpos, xrr_bitpos)), 0); | |
4201 | ||
4202 | /* Convert to the smaller type before masking out unwanted bits. */ | |
4203 | type = lntype; | |
4204 | if (lntype != rntype) | |
4205 | { | |
4206 | if (lnbitsize > rnbitsize) | |
4207 | { | |
4208 | lhs = convert (rntype, lhs); | |
4209 | ll_mask = convert (rntype, ll_mask); | |
4210 | type = rntype; | |
4211 | } | |
4212 | else if (lnbitsize < rnbitsize) | |
4213 | { | |
4214 | rhs = convert (lntype, rhs); | |
4215 | lr_mask = convert (lntype, lr_mask); | |
4216 | type = lntype; | |
4217 | } | |
4218 | } | |
4219 | ||
97ea7176 CH |
4220 | if (! all_ones_mask_p (ll_mask, ll_bitsize + rl_bitsize)) |
4221 | lhs = build (BIT_AND_EXPR, type, lhs, ll_mask); | |
4222 | ||
97ea7176 CH |
4223 | if (! all_ones_mask_p (lr_mask, lr_bitsize + rr_bitsize)) |
4224 | rhs = build (BIT_AND_EXPR, type, rhs, lr_mask); | |
4225 | ||
4226 | return build (wanted_code, truth_type, lhs, rhs); | |
4227 | } | |
6d716ca8 RS |
4228 | |
4229 | return 0; | |
4230 | } | |
4231 | ||
4232 | /* Handle the case of comparisons with constants. If there is something in | |
4233 | common between the masks, those bits of the constants must be the same. | |
4234 | If not, the condition is always false. Test for this to avoid generating | |
4235 | incorrect code below. */ | |
91d33e36 | 4236 | result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask, 0); |
6d716ca8 | 4237 | if (! integer_zerop (result) |
91d33e36 RS |
4238 | && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const, 0), |
4239 | const_binop (BIT_AND_EXPR, result, r_const, 0)) != 1) | |
6d716ca8 RS |
4240 | { |
4241 | if (wanted_code == NE_EXPR) | |
4242 | { | |
4243 | warning ("`or' of unmatched not-equal tests is always 1"); | |
4244 | return convert (truth_type, integer_one_node); | |
4245 | } | |
4246 | else | |
4247 | { | |
ab87f8c8 | 4248 | warning ("`and' of mutually exclusive equal-tests is always 0"); |
6d716ca8 RS |
4249 | return convert (truth_type, integer_zero_node); |
4250 | } | |
4251 | } | |
4252 | ||
4253 | /* Construct the expression we will return. First get the component | |
4254 | reference we will make. Unless the mask is all ones the width of | |
4255 | that field, perform the mask operation. Then compare with the | |
4256 | merged constant. */ | |
bd910dcf | 4257 | result = make_bit_field_ref (ll_inner, lntype, lnbitsize, lnbitpos, |
6d716ca8 RS |
4258 | ll_unsignedp || rl_unsignedp); |
4259 | ||
91d33e36 | 4260 | ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0); |
6d716ca8 | 4261 | if (! all_ones_mask_p (ll_mask, lnbitsize)) |
bd910dcf | 4262 | result = build (BIT_AND_EXPR, lntype, result, ll_mask); |
6d716ca8 RS |
4263 | |
4264 | return build (wanted_code, truth_type, result, | |
91d33e36 | 4265 | const_binop (BIT_IOR_EXPR, l_const, r_const, 0)); |
6d716ca8 RS |
4266 | } |
4267 | \f | |
b6cc0a72 | 4268 | /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a |
14a774a9 RK |
4269 | constant. */ |
4270 | ||
4271 | static tree | |
4272 | optimize_minmax_comparison (t) | |
4273 | tree t; | |
4274 | { | |
4275 | tree type = TREE_TYPE (t); | |
4276 | tree arg0 = TREE_OPERAND (t, 0); | |
4277 | enum tree_code op_code; | |
4278 | tree comp_const = TREE_OPERAND (t, 1); | |
4279 | tree minmax_const; | |
4280 | int consts_equal, consts_lt; | |
4281 | tree inner; | |
4282 | ||
4283 | STRIP_SIGN_NOPS (arg0); | |
4284 | ||
4285 | op_code = TREE_CODE (arg0); | |
4286 | minmax_const = TREE_OPERAND (arg0, 1); | |
4287 | consts_equal = tree_int_cst_equal (minmax_const, comp_const); | |
4288 | consts_lt = tree_int_cst_lt (minmax_const, comp_const); | |
4289 | inner = TREE_OPERAND (arg0, 0); | |
4290 | ||
4291 | /* If something does not permit us to optimize, return the original tree. */ | |
4292 | if ((op_code != MIN_EXPR && op_code != MAX_EXPR) | |
4293 | || TREE_CODE (comp_const) != INTEGER_CST | |
4294 | || TREE_CONSTANT_OVERFLOW (comp_const) | |
4295 | || TREE_CODE (minmax_const) != INTEGER_CST | |
4296 | || TREE_CONSTANT_OVERFLOW (minmax_const)) | |
4297 | return t; | |
4298 | ||
4299 | /* Now handle all the various comparison codes. We only handle EQ_EXPR | |
4300 | and GT_EXPR, doing the rest with recursive calls using logical | |
4301 | simplifications. */ | |
4302 | switch (TREE_CODE (t)) | |
4303 | { | |
4304 | case NE_EXPR: case LT_EXPR: case LE_EXPR: | |
4305 | return | |
4306 | invert_truthvalue (optimize_minmax_comparison (invert_truthvalue (t))); | |
4307 | ||
4308 | case GE_EXPR: | |
4309 | return | |
4310 | fold (build (TRUTH_ORIF_EXPR, type, | |
4311 | optimize_minmax_comparison | |
4312 | (build (EQ_EXPR, type, arg0, comp_const)), | |
4313 | optimize_minmax_comparison | |
4314 | (build (GT_EXPR, type, arg0, comp_const)))); | |
4315 | ||
4316 | case EQ_EXPR: | |
4317 | if (op_code == MAX_EXPR && consts_equal) | |
4318 | /* MAX (X, 0) == 0 -> X <= 0 */ | |
4319 | return fold (build (LE_EXPR, type, inner, comp_const)); | |
4320 | ||
4321 | else if (op_code == MAX_EXPR && consts_lt) | |
4322 | /* MAX (X, 0) == 5 -> X == 5 */ | |
4323 | return fold (build (EQ_EXPR, type, inner, comp_const)); | |
4324 | ||
4325 | else if (op_code == MAX_EXPR) | |
4326 | /* MAX (X, 0) == -1 -> false */ | |
4327 | return omit_one_operand (type, integer_zero_node, inner); | |
4328 | ||
4329 | else if (consts_equal) | |
4330 | /* MIN (X, 0) == 0 -> X >= 0 */ | |
4331 | return fold (build (GE_EXPR, type, inner, comp_const)); | |
4332 | ||
4333 | else if (consts_lt) | |
4334 | /* MIN (X, 0) == 5 -> false */ | |
4335 | return omit_one_operand (type, integer_zero_node, inner); | |
4336 | ||
4337 | else | |
4338 | /* MIN (X, 0) == -1 -> X == -1 */ | |
4339 | return fold (build (EQ_EXPR, type, inner, comp_const)); | |
4340 | ||
4341 | case GT_EXPR: | |
4342 | if (op_code == MAX_EXPR && (consts_equal || consts_lt)) | |
4343 | /* MAX (X, 0) > 0 -> X > 0 | |
4344 | MAX (X, 0) > 5 -> X > 5 */ | |
4345 | return fold (build (GT_EXPR, type, inner, comp_const)); | |
4346 | ||
4347 | else if (op_code == MAX_EXPR) | |
4348 | /* MAX (X, 0) > -1 -> true */ | |
4349 | return omit_one_operand (type, integer_one_node, inner); | |
4350 | ||
4351 | else if (op_code == MIN_EXPR && (consts_equal || consts_lt)) | |
4352 | /* MIN (X, 0) > 0 -> false | |
4353 | MIN (X, 0) > 5 -> false */ | |
4354 | return omit_one_operand (type, integer_zero_node, inner); | |
4355 | ||
4356 | else | |
4357 | /* MIN (X, 0) > -1 -> X > -1 */ | |
4358 | return fold (build (GT_EXPR, type, inner, comp_const)); | |
4359 | ||
4360 | default: | |
4361 | return t; | |
4362 | } | |
4363 | } | |
4364 | \f | |
1baa375f RK |
4365 | /* T is an integer expression that is being multiplied, divided, or taken a |
4366 | modulus (CODE says which and what kind of divide or modulus) by a | |
4367 | constant C. See if we can eliminate that operation by folding it with | |
4368 | other operations already in T. WIDE_TYPE, if non-null, is a type that | |
4369 | should be used for the computation if wider than our type. | |
4370 | ||
4371 | For example, if we are dividing (X * 8) + (Y + 16) by 4, we can return | |
8e1ca098 RH |
4372 | (X * 2) + (Y + 4). We must, however, be assured that either the original |
4373 | expression would not overflow or that overflow is undefined for the type | |
4374 | in the language in question. | |
4375 | ||
4376 | We also canonicalize (X + 7) * 4 into X * 4 + 28 in the hope that either | |
4377 | the machine has a multiply-accumulate insn or that this is part of an | |
4378 | addressing calculation. | |
1baa375f RK |
4379 | |
4380 | If we return a non-null expression, it is an equivalent form of the | |
4381 | original computation, but need not be in the original type. */ | |
4382 | ||
4383 | static tree | |
4384 | extract_muldiv (t, c, code, wide_type) | |
4385 | tree t; | |
4386 | tree c; | |
4387 | enum tree_code code; | |
4388 | tree wide_type; | |
4389 | { | |
4390 | tree type = TREE_TYPE (t); | |
4391 | enum tree_code tcode = TREE_CODE (t); | |
b6cc0a72 | 4392 | tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type)) |
1baa375f RK |
4393 | > GET_MODE_SIZE (TYPE_MODE (type))) |
4394 | ? wide_type : type); | |
4395 | tree t1, t2; | |
4396 | int same_p = tcode == code; | |
9d0878fd | 4397 | tree op0 = NULL_TREE, op1 = NULL_TREE; |
1baa375f RK |
4398 | |
4399 | /* Don't deal with constants of zero here; they confuse the code below. */ | |
4400 | if (integer_zerop (c)) | |
8e1ca098 | 4401 | return NULL_TREE; |
1baa375f RK |
4402 | |
4403 | if (TREE_CODE_CLASS (tcode) == '1') | |
4404 | op0 = TREE_OPERAND (t, 0); | |
4405 | ||
4406 | if (TREE_CODE_CLASS (tcode) == '2') | |
4407 | op0 = TREE_OPERAND (t, 0), op1 = TREE_OPERAND (t, 1); | |
4408 | ||
4409 | /* Note that we need not handle conditional operations here since fold | |
4410 | already handles those cases. So just do arithmetic here. */ | |
4411 | switch (tcode) | |
4412 | { | |
4413 | case INTEGER_CST: | |
4414 | /* For a constant, we can always simplify if we are a multiply | |
4415 | or (for divide and modulus) if it is a multiple of our constant. */ | |
4416 | if (code == MULT_EXPR | |
4417 | || integer_zerop (const_binop (TRUNC_MOD_EXPR, t, c, 0))) | |
4418 | return const_binop (code, convert (ctype, t), convert (ctype, c), 0); | |
4419 | break; | |
4420 | ||
4421 | case CONVERT_EXPR: case NON_LVALUE_EXPR: case NOP_EXPR: | |
eff9c80d RH |
4422 | /* If op0 is an expression, and is unsigned, and the type is |
4423 | smaller than ctype, then we cannot widen the expression. */ | |
4424 | if ((TREE_CODE_CLASS (TREE_CODE (op0)) == '<' | |
4425 | || TREE_CODE_CLASS (TREE_CODE (op0)) == '1' | |
4426 | || TREE_CODE_CLASS (TREE_CODE (op0)) == '2' | |
4427 | || TREE_CODE_CLASS (TREE_CODE (op0)) == 'e') | |
4428 | && TREE_UNSIGNED (TREE_TYPE (op0)) | |
7393c642 RK |
4429 | && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE |
4430 | && TYPE_IS_SIZETYPE (TREE_TYPE (op0))) | |
eff9c80d RH |
4431 | && (GET_MODE_SIZE (TYPE_MODE (ctype)) |
4432 | > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0))))) | |
4433 | break; | |
4434 | ||
1baa375f | 4435 | /* Pass the constant down and see if we can make a simplification. If |
59adecfa RK |
4436 | we can, replace this expression with the inner simplification for |
4437 | possible later conversion to our or some other type. */ | |
1baa375f RK |
4438 | if (0 != (t1 = extract_muldiv (op0, convert (TREE_TYPE (op0), c), code, |
4439 | code == MULT_EXPR ? ctype : NULL_TREE))) | |
4440 | return t1; | |
4441 | break; | |
4442 | ||
4443 | case NEGATE_EXPR: case ABS_EXPR: | |
4444 | if ((t1 = extract_muldiv (op0, c, code, wide_type)) != 0) | |
4445 | return fold (build1 (tcode, ctype, convert (ctype, t1))); | |
4446 | break; | |
4447 | ||
4448 | case MIN_EXPR: case MAX_EXPR: | |
13393c8a JW |
4449 | /* If widening the type changes the signedness, then we can't perform |
4450 | this optimization as that changes the result. */ | |
eff9c80d | 4451 | if (TREE_UNSIGNED (ctype) != TREE_UNSIGNED (type)) |
13393c8a JW |
4452 | break; |
4453 | ||
1baa375f RK |
4454 | /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */ |
4455 | if ((t1 = extract_muldiv (op0, c, code, wide_type)) != 0 | |
4456 | && (t2 = extract_muldiv (op1, c, code, wide_type)) != 0) | |
59adecfa RK |
4457 | { |
4458 | if (tree_int_cst_sgn (c) < 0) | |
4459 | tcode = (tcode == MIN_EXPR ? MAX_EXPR : MIN_EXPR); | |
4460 | ||
4461 | return fold (build (tcode, ctype, convert (ctype, t1), | |
4462 | convert (ctype, t2))); | |
4463 | } | |
1baa375f RK |
4464 | break; |
4465 | ||
4466 | case WITH_RECORD_EXPR: | |
4467 | if ((t1 = extract_muldiv (TREE_OPERAND (t, 0), c, code, wide_type)) != 0) | |
4468 | return build (WITH_RECORD_EXPR, TREE_TYPE (t1), t1, | |
4469 | TREE_OPERAND (t, 1)); | |
4470 | break; | |
4471 | ||
4472 | case SAVE_EXPR: | |
59adecfa RK |
4473 | /* If this has not been evaluated and the operand has no side effects, |
4474 | we can see if we can do something inside it and make a new one. | |
4475 | Note that this test is overly conservative since we can do this | |
4476 | if the only reason it had side effects is that it was another | |
4477 | similar SAVE_EXPR, but that isn't worth bothering with. */ | |
4478 | if (SAVE_EXPR_RTL (t) == 0 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)) | |
1baa375f RK |
4479 | && 0 != (t1 = extract_muldiv (TREE_OPERAND (t, 0), c, code, |
4480 | wide_type))) | |
fe375cf1 JJ |
4481 | { |
4482 | t1 = save_expr (t1); | |
4483 | if (SAVE_EXPR_PERSISTENT_P (t) && TREE_CODE (t1) == SAVE_EXPR) | |
4484 | SAVE_EXPR_PERSISTENT_P (t1) = 1; | |
4485 | if (is_pending_size (t)) | |
4486 | put_pending_size (t1); | |
4487 | return t1; | |
4488 | } | |
1baa375f RK |
4489 | break; |
4490 | ||
4491 | case LSHIFT_EXPR: case RSHIFT_EXPR: | |
4492 | /* If the second operand is constant, this is a multiplication | |
4493 | or floor division, by a power of two, so we can treat it that | |
4494 | way unless the multiplier or divisor overflows. */ | |
4495 | if (TREE_CODE (op1) == INTEGER_CST | |
d08230fe NC |
4496 | /* const_binop may not detect overflow correctly, |
4497 | so check for it explicitly here. */ | |
4498 | && TYPE_PRECISION (TREE_TYPE (size_one_node)) > TREE_INT_CST_LOW (op1) | |
4499 | && TREE_INT_CST_HIGH (op1) == 0 | |
1baa375f RK |
4500 | && 0 != (t1 = convert (ctype, |
4501 | const_binop (LSHIFT_EXPR, size_one_node, | |
4502 | op1, 0))) | |
4503 | && ! TREE_OVERFLOW (t1)) | |
4504 | return extract_muldiv (build (tcode == LSHIFT_EXPR | |
4505 | ? MULT_EXPR : FLOOR_DIV_EXPR, | |
4506 | ctype, convert (ctype, op0), t1), | |
4507 | c, code, wide_type); | |
4508 | break; | |
4509 | ||
4510 | case PLUS_EXPR: case MINUS_EXPR: | |
4511 | /* See if we can eliminate the operation on both sides. If we can, we | |
4512 | can return a new PLUS or MINUS. If we can't, the only remaining | |
4513 | cases where we can do anything are if the second operand is a | |
4514 | constant. */ | |
4515 | t1 = extract_muldiv (op0, c, code, wide_type); | |
4516 | t2 = extract_muldiv (op1, c, code, wide_type); | |
fba2c0cd JJ |
4517 | if (t1 != 0 && t2 != 0 |
4518 | && (code == MULT_EXPR | |
4519 | /* If not multiplication, we can only do this if either operand | |
4520 | is divisible by c. */ | |
4521 | || multiple_of_p (ctype, op0, c) | |
4522 | || multiple_of_p (ctype, op1, c))) | |
1baa375f RK |
4523 | return fold (build (tcode, ctype, convert (ctype, t1), |
4524 | convert (ctype, t2))); | |
1baa375f | 4525 | |
59adecfa RK |
4526 | /* If this was a subtraction, negate OP1 and set it to be an addition. |
4527 | This simplifies the logic below. */ | |
4528 | if (tcode == MINUS_EXPR) | |
4529 | tcode = PLUS_EXPR, op1 = negate_expr (op1); | |
4530 | ||
f9011d04 RK |
4531 | if (TREE_CODE (op1) != INTEGER_CST) |
4532 | break; | |
4533 | ||
59adecfa RK |
4534 | /* If either OP1 or C are negative, this optimization is not safe for |
4535 | some of the division and remainder types while for others we need | |
4536 | to change the code. */ | |
4537 | if (tree_int_cst_sgn (op1) < 0 || tree_int_cst_sgn (c) < 0) | |
4538 | { | |
4539 | if (code == CEIL_DIV_EXPR) | |
4540 | code = FLOOR_DIV_EXPR; | |
4541 | else if (code == CEIL_MOD_EXPR) | |
4542 | code = FLOOR_MOD_EXPR; | |
4543 | else if (code == FLOOR_DIV_EXPR) | |
4544 | code = CEIL_DIV_EXPR; | |
4545 | else if (code == FLOOR_MOD_EXPR) | |
4546 | code = CEIL_MOD_EXPR; | |
4547 | else if (code != MULT_EXPR) | |
4548 | break; | |
4549 | } | |
4550 | ||
12644a9a TM |
4551 | /* If it's a multiply or a division/modulus operation of a multiple |
4552 | of our constant, do the operation and verify it doesn't overflow. */ | |
4553 | if (code == MULT_EXPR | |
4554 | || integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0))) | |
4555 | { | |
4556 | op1 = const_binop (code, convert (ctype, op1), convert (ctype, c), 0); | |
4557 | if (op1 == 0 || TREE_OVERFLOW (op1)) | |
4558 | break; | |
4559 | } | |
4560 | else | |
4561 | break; | |
59adecfa | 4562 | |
23cdce68 RH |
4563 | /* If we have an unsigned type is not a sizetype, we cannot widen |
4564 | the operation since it will change the result if the original | |
4565 | computation overflowed. */ | |
4566 | if (TREE_UNSIGNED (ctype) | |
7393c642 | 4567 | && ! (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)) |
23cdce68 RH |
4568 | && ctype != type) |
4569 | break; | |
4570 | ||
1baa375f | 4571 | /* If we were able to eliminate our operation from the first side, |
59adecfa RK |
4572 | apply our operation to the second side and reform the PLUS. */ |
4573 | if (t1 != 0 && (TREE_CODE (t1) != code || code == MULT_EXPR)) | |
4574 | return fold (build (tcode, ctype, convert (ctype, t1), op1)); | |
1baa375f RK |
4575 | |
4576 | /* The last case is if we are a multiply. In that case, we can | |
4577 | apply the distributive law to commute the multiply and addition | |
30f7a378 | 4578 | if the multiplication of the constants doesn't overflow. */ |
59adecfa | 4579 | if (code == MULT_EXPR) |
1baa375f RK |
4580 | return fold (build (tcode, ctype, fold (build (code, ctype, |
4581 | convert (ctype, op0), | |
4582 | convert (ctype, c))), | |
59adecfa | 4583 | op1)); |
1baa375f RK |
4584 | |
4585 | break; | |
4586 | ||
4587 | case MULT_EXPR: | |
4588 | /* We have a special case here if we are doing something like | |
4589 | (C * 8) % 4 since we know that's zero. */ | |
4590 | if ((code == TRUNC_MOD_EXPR || code == CEIL_MOD_EXPR | |
4591 | || code == FLOOR_MOD_EXPR || code == ROUND_MOD_EXPR) | |
4592 | && TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST | |
4593 | && integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0))) | |
4594 | return omit_one_operand (type, integer_zero_node, op0); | |
4595 | ||
30f7a378 | 4596 | /* ... fall through ... */ |
1baa375f RK |
4597 | |
4598 | case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR: | |
4599 | case ROUND_DIV_EXPR: case EXACT_DIV_EXPR: | |
4600 | /* If we can extract our operation from the LHS, do so and return a | |
4601 | new operation. Likewise for the RHS from a MULT_EXPR. Otherwise, | |
4602 | do something only if the second operand is a constant. */ | |
4603 | if (same_p | |
4604 | && (t1 = extract_muldiv (op0, c, code, wide_type)) != 0) | |
4605 | return fold (build (tcode, ctype, convert (ctype, t1), | |
4606 | convert (ctype, op1))); | |
4607 | else if (tcode == MULT_EXPR && code == MULT_EXPR | |
4608 | && (t1 = extract_muldiv (op1, c, code, wide_type)) != 0) | |
4609 | return fold (build (tcode, ctype, convert (ctype, op0), | |
4610 | convert (ctype, t1))); | |
4611 | else if (TREE_CODE (op1) != INTEGER_CST) | |
4612 | return 0; | |
4613 | ||
4614 | /* If these are the same operation types, we can associate them | |
4615 | assuming no overflow. */ | |
4616 | if (tcode == code | |
4617 | && 0 != (t1 = const_binop (MULT_EXPR, convert (ctype, op1), | |
4618 | convert (ctype, c), 0)) | |
4619 | && ! TREE_OVERFLOW (t1)) | |
4620 | return fold (build (tcode, ctype, convert (ctype, op0), t1)); | |
4621 | ||
4622 | /* If these operations "cancel" each other, we have the main | |
4623 | optimizations of this pass, which occur when either constant is a | |
4624 | multiple of the other, in which case we replace this with either an | |
b6cc0a72 | 4625 | operation or CODE or TCODE. |
8e1ca098 RH |
4626 | |
4627 | If we have an unsigned type that is not a sizetype, we canot do | |
4628 | this since it will change the result if the original computation | |
4629 | overflowed. */ | |
4630 | if ((! TREE_UNSIGNED (ctype) | |
7393c642 | 4631 | || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype))) |
8e1ca098 RH |
4632 | && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR) |
4633 | || (tcode == MULT_EXPR | |
4634 | && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR | |
4635 | && code != FLOOR_MOD_EXPR && code != ROUND_MOD_EXPR))) | |
1baa375f RK |
4636 | { |
4637 | if (integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0))) | |
4638 | return fold (build (tcode, ctype, convert (ctype, op0), | |
4639 | convert (ctype, | |
4640 | const_binop (TRUNC_DIV_EXPR, | |
4641 | op1, c, 0)))); | |
4642 | else if (integer_zerop (const_binop (TRUNC_MOD_EXPR, c, op1, 0))) | |
4643 | return fold (build (code, ctype, convert (ctype, op0), | |
4644 | convert (ctype, | |
4645 | const_binop (TRUNC_DIV_EXPR, | |
4646 | c, op1, 0)))); | |
4647 | } | |
4648 | break; | |
4649 | ||
4650 | default: | |
4651 | break; | |
4652 | } | |
4653 | ||
4654 | return 0; | |
4655 | } | |
4656 | \f | |
b5f3b6b6 RK |
4657 | /* If T contains a COMPOUND_EXPR which was inserted merely to evaluate |
4658 | S, a SAVE_EXPR, return the expression actually being evaluated. Note | |
4659 | that we may sometimes modify the tree. */ | |
4660 | ||
4661 | static tree | |
4662 | strip_compound_expr (t, s) | |
4663 | tree t; | |
4664 | tree s; | |
4665 | { | |
b5f3b6b6 RK |
4666 | enum tree_code code = TREE_CODE (t); |
4667 | ||
4668 | /* See if this is the COMPOUND_EXPR we want to eliminate. */ | |
4669 | if (code == COMPOUND_EXPR && TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR | |
4670 | && TREE_OPERAND (TREE_OPERAND (t, 0), 0) == s) | |
4671 | return TREE_OPERAND (t, 1); | |
4672 | ||
4673 | /* See if this is a COND_EXPR or a simple arithmetic operator. We | |
4674 | don't bother handling any other types. */ | |
4675 | else if (code == COND_EXPR) | |
4676 | { | |
4677 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
4678 | TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s); | |
4679 | TREE_OPERAND (t, 2) = strip_compound_expr (TREE_OPERAND (t, 2), s); | |
4680 | } | |
4681 | else if (TREE_CODE_CLASS (code) == '1') | |
4682 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
4683 | else if (TREE_CODE_CLASS (code) == '<' | |
4684 | || TREE_CODE_CLASS (code) == '2') | |
4685 | { | |
4686 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
4687 | TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s); | |
4688 | } | |
4689 | ||
4690 | return t; | |
4691 | } | |
4692 | \f | |
f628873f MM |
4693 | /* Return a node which has the indicated constant VALUE (either 0 or |
4694 | 1), and is of the indicated TYPE. */ | |
4695 | ||
83e0821b | 4696 | static tree |
f628873f MM |
4697 | constant_boolean_node (value, type) |
4698 | int value; | |
4699 | tree type; | |
4700 | { | |
4701 | if (type == integer_type_node) | |
4702 | return value ? integer_one_node : integer_zero_node; | |
4703 | else if (TREE_CODE (type) == BOOLEAN_TYPE) | |
4704 | return truthvalue_conversion (value ? integer_one_node : | |
b6cc0a72 KH |
4705 | integer_zero_node); |
4706 | else | |
f628873f MM |
4707 | { |
4708 | tree t = build_int_2 (value, 0); | |
d4b60170 | 4709 | |
f628873f MM |
4710 | TREE_TYPE (t) = type; |
4711 | return t; | |
4712 | } | |
4713 | } | |
4714 | ||
ab87f8c8 JL |
4715 | /* Utility function for the following routine, to see how complex a nesting of |
4716 | COND_EXPRs can be. EXPR is the expression and LIMIT is a count beyond which | |
4717 | we don't care (to avoid spending too much time on complex expressions.). */ | |
4718 | ||
4719 | static int | |
4720 | count_cond (expr, lim) | |
4721 | tree expr; | |
4722 | int lim; | |
4723 | { | |
d6edb99e | 4724 | int ctrue, cfalse; |
ab87f8c8 JL |
4725 | |
4726 | if (TREE_CODE (expr) != COND_EXPR) | |
4727 | return 0; | |
4728 | else if (lim <= 0) | |
4729 | return 0; | |
4730 | ||
d6edb99e ZW |
4731 | ctrue = count_cond (TREE_OPERAND (expr, 1), lim - 1); |
4732 | cfalse = count_cond (TREE_OPERAND (expr, 2), lim - 1 - ctrue); | |
4733 | return MIN (lim, 1 + ctrue + cfalse); | |
ab87f8c8 | 4734 | } |
68626d4f MM |
4735 | |
4736 | /* Transform `a + (b ? x : y)' into `x ? (a + b) : (a + y)'. | |
4737 | Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here | |
4738 | CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)' | |
4739 | expression, and ARG to `a'. If COND_FIRST_P is non-zero, then the | |
4740 | COND is the first argument to CODE; otherwise (as in the example | |
4741 | given here), it is the second argument. TYPE is the type of the | |
4742 | original expression. */ | |
4743 | ||
4744 | static tree | |
4745 | fold_binary_op_with_conditional_arg (code, type, cond, arg, cond_first_p) | |
4746 | enum tree_code code; | |
4747 | tree type; | |
4748 | tree cond; | |
4749 | tree arg; | |
4750 | int cond_first_p; | |
4751 | { | |
4752 | tree test, true_value, false_value; | |
4753 | tree lhs = NULL_TREE; | |
4754 | tree rhs = NULL_TREE; | |
4755 | /* In the end, we'll produce a COND_EXPR. Both arms of the | |
4756 | conditional expression will be binary operations. The left-hand | |
4757 | side of the expression to be executed if the condition is true | |
4758 | will be pointed to by TRUE_LHS. Similarly, the right-hand side | |
4759 | of the expression to be executed if the condition is true will be | |
4760 | pointed to by TRUE_RHS. FALSE_LHS and FALSE_RHS are analagous -- | |
4761 | but apply to the expression to be executed if the conditional is | |
4762 | false. */ | |
4763 | tree *true_lhs; | |
4764 | tree *true_rhs; | |
4765 | tree *false_lhs; | |
4766 | tree *false_rhs; | |
4767 | /* These are the codes to use for the left-hand side and right-hand | |
4768 | side of the COND_EXPR. Normally, they are the same as CODE. */ | |
4769 | enum tree_code lhs_code = code; | |
4770 | enum tree_code rhs_code = code; | |
4771 | /* And these are the types of the expressions. */ | |
4772 | tree lhs_type = type; | |
4773 | tree rhs_type = type; | |
4774 | ||
4775 | if (cond_first_p) | |
4776 | { | |
4777 | true_rhs = false_rhs = &arg; | |
4778 | true_lhs = &true_value; | |
4779 | false_lhs = &false_value; | |
4780 | } | |
4781 | else | |
4782 | { | |
4783 | true_lhs = false_lhs = &arg; | |
4784 | true_rhs = &true_value; | |
4785 | false_rhs = &false_value; | |
4786 | } | |
4787 | ||
4788 | if (TREE_CODE (cond) == COND_EXPR) | |
4789 | { | |
4790 | test = TREE_OPERAND (cond, 0); | |
4791 | true_value = TREE_OPERAND (cond, 1); | |
4792 | false_value = TREE_OPERAND (cond, 2); | |
4793 | /* If this operand throws an expression, then it does not make | |
4794 | sense to try to perform a logical or arithmetic operation | |
4795 | involving it. Instead of building `a + throw 3' for example, | |
4796 | we simply build `a, throw 3'. */ | |
4797 | if (VOID_TYPE_P (TREE_TYPE (true_value))) | |
4798 | { | |
4799 | lhs_code = COMPOUND_EXPR; | |
4800 | if (!cond_first_p) | |
4801 | lhs_type = void_type_node; | |
4802 | } | |
4803 | if (VOID_TYPE_P (TREE_TYPE (false_value))) | |
4804 | { | |
4805 | rhs_code = COMPOUND_EXPR; | |
4806 | if (!cond_first_p) | |
4807 | rhs_type = void_type_node; | |
4808 | } | |
4809 | } | |
4810 | else | |
4811 | { | |
4812 | tree testtype = TREE_TYPE (cond); | |
4813 | test = cond; | |
4814 | true_value = convert (testtype, integer_one_node); | |
4815 | false_value = convert (testtype, integer_zero_node); | |
4816 | } | |
4817 | ||
4818 | /* If ARG is complex we want to make sure we only evaluate | |
4819 | it once. Though this is only required if it is volatile, it | |
4820 | might be more efficient even if it is not. However, if we | |
4821 | succeed in folding one part to a constant, we do not need | |
4822 | to make this SAVE_EXPR. Since we do this optimization | |
4823 | primarily to see if we do end up with constant and this | |
4824 | SAVE_EXPR interferes with later optimizations, suppressing | |
4825 | it when we can is important. | |
4826 | ||
4827 | If we are not in a function, we can't make a SAVE_EXPR, so don't | |
4828 | try to do so. Don't try to see if the result is a constant | |
4829 | if an arm is a COND_EXPR since we get exponential behavior | |
4830 | in that case. */ | |
4831 | ||
4832 | if (TREE_CODE (arg) != SAVE_EXPR && ! TREE_CONSTANT (arg) | |
4833 | && global_bindings_p () == 0 | |
4834 | && ((TREE_CODE (arg) != VAR_DECL | |
4835 | && TREE_CODE (arg) != PARM_DECL) | |
4836 | || TREE_SIDE_EFFECTS (arg))) | |
4837 | { | |
4838 | if (TREE_CODE (true_value) != COND_EXPR) | |
4839 | lhs = fold (build (lhs_code, lhs_type, *true_lhs, *true_rhs)); | |
4840 | ||
4841 | if (TREE_CODE (false_value) != COND_EXPR) | |
4842 | rhs = fold (build (rhs_code, rhs_type, *false_lhs, *false_rhs)); | |
4843 | ||
4844 | if ((lhs == 0 || ! TREE_CONSTANT (lhs)) | |
4845 | && (rhs == 0 || !TREE_CONSTANT (rhs))) | |
4846 | arg = save_expr (arg), lhs = rhs = 0; | |
4847 | } | |
4848 | ||
4849 | if (lhs == 0) | |
4850 | lhs = fold (build (lhs_code, lhs_type, *true_lhs, *true_rhs)); | |
4851 | if (rhs == 0) | |
4852 | rhs = fold (build (rhs_code, rhs_type, *false_lhs, *false_rhs)); | |
4853 | ||
4854 | test = fold (build (COND_EXPR, type, test, lhs, rhs)); | |
4855 | ||
4856 | if (TREE_CODE (arg) == SAVE_EXPR) | |
4857 | return build (COMPOUND_EXPR, type, | |
4858 | convert (void_type_node, arg), | |
4859 | strip_compound_expr (test, arg)); | |
4860 | else | |
4861 | return convert (type, test); | |
4862 | } | |
4863 | ||
ab87f8c8 | 4864 | \f |
6d716ca8 RS |
4865 | /* Perform constant folding and related simplification of EXPR. |
4866 | The related simplifications include x*1 => x, x*0 => 0, etc., | |
4867 | and application of the associative law. | |
4868 | NOP_EXPR conversions may be removed freely (as long as we | |
4869 | are careful not to change the C type of the overall expression) | |
4870 | We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR, | |
4871 | but we can constant-fold them if they have constant operands. */ | |
4872 | ||
4873 | tree | |
b6cc0a72 | 4874 | fold (expr) |
6d716ca8 RS |
4875 | tree expr; |
4876 | { | |
4877 | register tree t = expr; | |
4878 | tree t1 = NULL_TREE; | |
c05a9b68 | 4879 | tree tem; |
6d716ca8 | 4880 | tree type = TREE_TYPE (expr); |
4e86caed | 4881 | register tree arg0 = NULL_TREE, arg1 = NULL_TREE; |
6d716ca8 | 4882 | register enum tree_code code = TREE_CODE (t); |
1796dff4 | 4883 | register int kind = TREE_CODE_CLASS (code); |
c05a9b68 | 4884 | int invert; |
6d716ca8 RS |
4885 | /* WINS will be nonzero when the switch is done |
4886 | if all operands are constant. */ | |
6d716ca8 RS |
4887 | int wins = 1; |
4888 | ||
b6cc0a72 | 4889 | /* Don't try to process an RTL_EXPR since its operands aren't trees. |
5fd7f37d | 4890 | Likewise for a SAVE_EXPR that's already been evaluated. */ |
dea8be3e | 4891 | if (code == RTL_EXPR || (code == SAVE_EXPR && SAVE_EXPR_RTL (t) != 0)) |
ac27d589 RK |
4892 | return t; |
4893 | ||
1796dff4 RH |
4894 | /* Return right away if a constant. */ |
4895 | if (kind == 'c') | |
4896 | return t; | |
b6cc0a72 | 4897 | |
dbecbbe4 JL |
4898 | #ifdef MAX_INTEGER_COMPUTATION_MODE |
4899 | check_max_integer_computation_mode (expr); | |
4900 | #endif | |
4901 | ||
1b81aa14 RS |
4902 | if (code == NOP_EXPR || code == FLOAT_EXPR || code == CONVERT_EXPR) |
4903 | { | |
1cc1b11a RS |
4904 | tree subop; |
4905 | ||
1b81aa14 RS |
4906 | /* Special case for conversion ops that can have fixed point args. */ |
4907 | arg0 = TREE_OPERAND (t, 0); | |
4908 | ||
4909 | /* Don't use STRIP_NOPS, because signedness of argument type matters. */ | |
4910 | if (arg0 != 0) | |
14a774a9 | 4911 | STRIP_SIGN_NOPS (arg0); |
1b81aa14 | 4912 | |
1cc1b11a RS |
4913 | if (arg0 != 0 && TREE_CODE (arg0) == COMPLEX_CST) |
4914 | subop = TREE_REALPART (arg0); | |
4915 | else | |
4916 | subop = arg0; | |
4917 | ||
4918 | if (subop != 0 && TREE_CODE (subop) != INTEGER_CST | |
1b81aa14 | 4919 | #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) |
1cc1b11a | 4920 | && TREE_CODE (subop) != REAL_CST |
1b81aa14 RS |
4921 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ |
4922 | ) | |
4923 | /* Note that TREE_CONSTANT isn't enough: | |
4924 | static var addresses are constant but we can't | |
4925 | do arithmetic on them. */ | |
4926 | wins = 0; | |
4927 | } | |
efd58783 | 4928 | else if (IS_EXPR_CODE_CLASS (kind) || kind == 'r') |
6d716ca8 | 4929 | { |
dea8be3e | 4930 | register int len = first_rtl_op (code); |
6d716ca8 RS |
4931 | register int i; |
4932 | for (i = 0; i < len; i++) | |
4933 | { | |
4934 | tree op = TREE_OPERAND (t, i); | |
1cc1b11a | 4935 | tree subop; |
6d716ca8 RS |
4936 | |
4937 | if (op == 0) | |
4938 | continue; /* Valid for CALL_EXPR, at least. */ | |
4939 | ||
b8a91430 RK |
4940 | if (kind == '<' || code == RSHIFT_EXPR) |
4941 | { | |
4942 | /* Signedness matters here. Perhaps we can refine this | |
4943 | later. */ | |
14a774a9 | 4944 | STRIP_SIGN_NOPS (op); |
b8a91430 RK |
4945 | } |
4946 | else | |
13eb1f7f RK |
4947 | /* Strip any conversions that don't change the mode. */ |
4948 | STRIP_NOPS (op); | |
b6cc0a72 | 4949 | |
1cc1b11a RS |
4950 | if (TREE_CODE (op) == COMPLEX_CST) |
4951 | subop = TREE_REALPART (op); | |
4952 | else | |
4953 | subop = op; | |
4954 | ||
4955 | if (TREE_CODE (subop) != INTEGER_CST | |
6d716ca8 | 4956 | #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) |
1cc1b11a | 4957 | && TREE_CODE (subop) != REAL_CST |
6d716ca8 RS |
4958 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ |
4959 | ) | |
4960 | /* Note that TREE_CONSTANT isn't enough: | |
4961 | static var addresses are constant but we can't | |
4962 | do arithmetic on them. */ | |
4963 | wins = 0; | |
4964 | ||
4965 | if (i == 0) | |
4966 | arg0 = op; | |
4967 | else if (i == 1) | |
4968 | arg1 = op; | |
4969 | } | |
4970 | } | |
4971 | ||
4972 | /* If this is a commutative operation, and ARG0 is a constant, move it | |
4973 | to ARG1 to reduce the number of tests below. */ | |
4974 | if ((code == PLUS_EXPR || code == MULT_EXPR || code == MIN_EXPR | |
4975 | || code == MAX_EXPR || code == BIT_IOR_EXPR || code == BIT_XOR_EXPR | |
4976 | || code == BIT_AND_EXPR) | |
4977 | && (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)) | |
4978 | { | |
c05a9b68 | 4979 | tem = arg0; arg0 = arg1; arg1 = tem; |
6d716ca8 | 4980 | |
c05a9b68 RS |
4981 | tem = TREE_OPERAND (t, 0); TREE_OPERAND (t, 0) = TREE_OPERAND (t, 1); |
4982 | TREE_OPERAND (t, 1) = tem; | |
6d716ca8 RS |
4983 | } |
4984 | ||
4985 | /* Now WINS is set as described above, | |
4986 | ARG0 is the first operand of EXPR, | |
4987 | and ARG1 is the second operand (if it has more than one operand). | |
4988 | ||
4989 | First check for cases where an arithmetic operation is applied to a | |
4990 | compound, conditional, or comparison operation. Push the arithmetic | |
4991 | operation inside the compound or conditional to see if any folding | |
4992 | can then be done. Convert comparison to conditional for this purpose. | |
4993 | The also optimizes non-constant cases that used to be done in | |
96d4cf0a RK |
4994 | expand_expr. |
4995 | ||
fba5638f | 4996 | Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR, |
61f275ff RK |
4997 | one of the operands is a comparison and the other is a comparison, a |
4998 | BIT_AND_EXPR with the constant 1, or a truth value. In that case, the | |
4999 | code below would make the expression more complex. Change it to a | |
b6cc0a72 | 5000 | TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to |
2df46b06 | 5001 | TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */ |
96d4cf0a | 5002 | |
2df46b06 RK |
5003 | if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR |
5004 | || code == EQ_EXPR || code == NE_EXPR) | |
61f275ff RK |
5005 | && ((truth_value_p (TREE_CODE (arg0)) |
5006 | && (truth_value_p (TREE_CODE (arg1)) | |
96d4cf0a RK |
5007 | || (TREE_CODE (arg1) == BIT_AND_EXPR |
5008 | && integer_onep (TREE_OPERAND (arg1, 1))))) | |
61f275ff RK |
5009 | || (truth_value_p (TREE_CODE (arg1)) |
5010 | && (truth_value_p (TREE_CODE (arg0)) | |
96d4cf0a RK |
5011 | || (TREE_CODE (arg0) == BIT_AND_EXPR |
5012 | && integer_onep (TREE_OPERAND (arg0, 1))))))) | |
2df46b06 RK |
5013 | { |
5014 | t = fold (build (code == BIT_AND_EXPR ? TRUTH_AND_EXPR | |
5015 | : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR | |
5016 | : TRUTH_XOR_EXPR, | |
5017 | type, arg0, arg1)); | |
5018 | ||
5019 | if (code == EQ_EXPR) | |
5020 | t = invert_truthvalue (t); | |
5021 | ||
5022 | return t; | |
5023 | } | |
96d4cf0a | 5024 | |
6d716ca8 RS |
5025 | if (TREE_CODE_CLASS (code) == '1') |
5026 | { | |
5027 | if (TREE_CODE (arg0) == COMPOUND_EXPR) | |
5028 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
5029 | fold (build1 (code, type, TREE_OPERAND (arg0, 1)))); | |
5030 | else if (TREE_CODE (arg0) == COND_EXPR) | |
b8eb43a2 RK |
5031 | { |
5032 | t = fold (build (COND_EXPR, type, TREE_OPERAND (arg0, 0), | |
5033 | fold (build1 (code, type, TREE_OPERAND (arg0, 1))), | |
5034 | fold (build1 (code, type, TREE_OPERAND (arg0, 2))))); | |
5035 | ||
5036 | /* If this was a conversion, and all we did was to move into | |
e1f56f62 RK |
5037 | inside the COND_EXPR, bring it back out. But leave it if |
5038 | it is a conversion from integer to integer and the | |
5039 | result precision is no wider than a word since such a | |
5040 | conversion is cheap and may be optimized away by combine, | |
5041 | while it couldn't if it were outside the COND_EXPR. Then return | |
5042 | so we don't get into an infinite recursion loop taking the | |
5043 | conversion out and then back in. */ | |
b8eb43a2 RK |
5044 | |
5045 | if ((code == NOP_EXPR || code == CONVERT_EXPR | |
5046 | || code == NON_LVALUE_EXPR) | |
5047 | && TREE_CODE (t) == COND_EXPR | |
5048 | && TREE_CODE (TREE_OPERAND (t, 1)) == code | |
459a2653 RK |
5049 | && TREE_CODE (TREE_OPERAND (t, 2)) == code |
5050 | && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)) | |
e1f56f62 RK |
5051 | == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 2), 0))) |
5052 | && ! (INTEGRAL_TYPE_P (TREE_TYPE (t)) | |
d4b60170 RK |
5053 | && (INTEGRAL_TYPE_P |
5054 | (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)))) | |
e1f56f62 | 5055 | && TYPE_PRECISION (TREE_TYPE (t)) <= BITS_PER_WORD)) |
b8eb43a2 RK |
5056 | t = build1 (code, type, |
5057 | build (COND_EXPR, | |
d4b60170 RK |
5058 | TREE_TYPE (TREE_OPERAND |
5059 | (TREE_OPERAND (t, 1), 0)), | |
b8eb43a2 RK |
5060 | TREE_OPERAND (t, 0), |
5061 | TREE_OPERAND (TREE_OPERAND (t, 1), 0), | |
5062 | TREE_OPERAND (TREE_OPERAND (t, 2), 0))); | |
5063 | return t; | |
5064 | } | |
b6cc0a72 | 5065 | else if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<') |
6d716ca8 RS |
5066 | return fold (build (COND_EXPR, type, arg0, |
5067 | fold (build1 (code, type, integer_one_node)), | |
5068 | fold (build1 (code, type, integer_zero_node)))); | |
5069 | } | |
96d4cf0a RK |
5070 | else if (TREE_CODE_CLASS (code) == '2' |
5071 | || TREE_CODE_CLASS (code) == '<') | |
6d716ca8 RS |
5072 | { |
5073 | if (TREE_CODE (arg1) == COMPOUND_EXPR) | |
5074 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), | |
96d4cf0a RK |
5075 | fold (build (code, type, |
5076 | arg0, TREE_OPERAND (arg1, 1)))); | |
f0eebf28 RK |
5077 | else if ((TREE_CODE (arg1) == COND_EXPR |
5078 | || (TREE_CODE_CLASS (TREE_CODE (arg1)) == '<' | |
5079 | && TREE_CODE_CLASS (code) != '<')) | |
ab87f8c8 JL |
5080 | && (TREE_CODE (arg0) != COND_EXPR |
5081 | || count_cond (arg0, 25) + count_cond (arg1, 25) <= 25) | |
9ec36da5 | 5082 | && (! TREE_SIDE_EFFECTS (arg0) |
c5c76735 | 5083 | || (global_bindings_p () == 0 |
9ec36da5 | 5084 | && ! contains_placeholder_p (arg0)))) |
68626d4f MM |
5085 | return |
5086 | fold_binary_op_with_conditional_arg (code, type, arg1, arg0, | |
5087 | /*cond_first_p=*/0); | |
6d716ca8 RS |
5088 | else if (TREE_CODE (arg0) == COMPOUND_EXPR) |
5089 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
5090 | fold (build (code, type, TREE_OPERAND (arg0, 1), arg1))); | |
f0eebf28 RK |
5091 | else if ((TREE_CODE (arg0) == COND_EXPR |
5092 | || (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' | |
5093 | && TREE_CODE_CLASS (code) != '<')) | |
ab87f8c8 JL |
5094 | && (TREE_CODE (arg1) != COND_EXPR |
5095 | || count_cond (arg0, 25) + count_cond (arg1, 25) <= 25) | |
9ec36da5 | 5096 | && (! TREE_SIDE_EFFECTS (arg1) |
c5c76735 | 5097 | || (global_bindings_p () == 0 |
9ec36da5 | 5098 | && ! contains_placeholder_p (arg1)))) |
68626d4f MM |
5099 | return |
5100 | fold_binary_op_with_conditional_arg (code, type, arg0, arg1, | |
5101 | /*cond_first_p=*/1); | |
6d716ca8 | 5102 | } |
c05a9b68 RS |
5103 | else if (TREE_CODE_CLASS (code) == '<' |
5104 | && TREE_CODE (arg0) == COMPOUND_EXPR) | |
5105 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
5106 | fold (build (code, type, TREE_OPERAND (arg0, 1), arg1))); | |
5107 | else if (TREE_CODE_CLASS (code) == '<' | |
5108 | && TREE_CODE (arg1) == COMPOUND_EXPR) | |
5109 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), | |
5110 | fold (build (code, type, arg0, TREE_OPERAND (arg1, 1)))); | |
b6cc0a72 | 5111 | |
6d716ca8 RS |
5112 | switch (code) |
5113 | { | |
5114 | case INTEGER_CST: | |
5115 | case REAL_CST: | |
5116 | case STRING_CST: | |
5117 | case COMPLEX_CST: | |
5118 | case CONSTRUCTOR: | |
5119 | return t; | |
5120 | ||
5121 | case CONST_DECL: | |
5122 | return fold (DECL_INITIAL (t)); | |
5123 | ||
5124 | case NOP_EXPR: | |
5125 | case FLOAT_EXPR: | |
5126 | case CONVERT_EXPR: | |
5127 | case FIX_TRUNC_EXPR: | |
5128 | /* Other kinds of FIX are not handled properly by fold_convert. */ | |
33558beb | 5129 | |
e1f56f62 RK |
5130 | if (TREE_TYPE (TREE_OPERAND (t, 0)) == TREE_TYPE (t)) |
5131 | return TREE_OPERAND (t, 0); | |
5132 | ||
7e139075 RK |
5133 | /* Handle cases of two conversions in a row. */ |
5134 | if (TREE_CODE (TREE_OPERAND (t, 0)) == NOP_EXPR | |
5135 | || TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR) | |
5136 | { | |
5137 | tree inside_type = TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
5138 | tree inter_type = TREE_TYPE (TREE_OPERAND (t, 0)); | |
5139 | tree final_type = TREE_TYPE (t); | |
5140 | int inside_int = INTEGRAL_TYPE_P (inside_type); | |
7f0b305c | 5141 | int inside_ptr = POINTER_TYPE_P (inside_type); |
7e139075 | 5142 | int inside_float = FLOAT_TYPE_P (inside_type); |
770ae6cc | 5143 | unsigned int inside_prec = TYPE_PRECISION (inside_type); |
7e139075 RK |
5144 | int inside_unsignedp = TREE_UNSIGNED (inside_type); |
5145 | int inter_int = INTEGRAL_TYPE_P (inter_type); | |
7f0b305c | 5146 | int inter_ptr = POINTER_TYPE_P (inter_type); |
7e139075 | 5147 | int inter_float = FLOAT_TYPE_P (inter_type); |
770ae6cc | 5148 | unsigned int inter_prec = TYPE_PRECISION (inter_type); |
7e139075 RK |
5149 | int inter_unsignedp = TREE_UNSIGNED (inter_type); |
5150 | int final_int = INTEGRAL_TYPE_P (final_type); | |
7f0b305c | 5151 | int final_ptr = POINTER_TYPE_P (final_type); |
7e139075 | 5152 | int final_float = FLOAT_TYPE_P (final_type); |
770ae6cc | 5153 | unsigned int final_prec = TYPE_PRECISION (final_type); |
7e139075 RK |
5154 | int final_unsignedp = TREE_UNSIGNED (final_type); |
5155 | ||
b6cc0a72 | 5156 | /* In addition to the cases of two conversions in a row |
7e139075 RK |
5157 | handled below, if we are converting something to its own |
5158 | type via an object of identical or wider precision, neither | |
5159 | conversion is needed. */ | |
30355eaa | 5160 | if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (final_type) |
7e139075 RK |
5161 | && ((inter_int && final_int) || (inter_float && final_float)) |
5162 | && inter_prec >= final_prec) | |
72bd1f9e | 5163 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
7e139075 RK |
5164 | |
5165 | /* Likewise, if the intermediate and final types are either both | |
5166 | float or both integer, we don't need the middle conversion if | |
5167 | it is wider than the final type and doesn't change the signedness | |
7f0b305c | 5168 | (for integers). Avoid this if the final type is a pointer |
410d3f5d RK |
5169 | since then we sometimes need the inner conversion. Likewise if |
5170 | the outer has a precision not equal to the size of its mode. */ | |
7e139075 RK |
5171 | if ((((inter_int || inter_ptr) && (inside_int || inside_ptr)) |
5172 | || (inter_float && inside_float)) | |
5173 | && inter_prec >= inside_prec | |
7f0b305c | 5174 | && (inter_float || inter_unsignedp == inside_unsignedp) |
410d3f5d RK |
5175 | && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type)) |
5176 | && TYPE_MODE (final_type) == TYPE_MODE (inter_type)) | |
7f0b305c | 5177 | && ! final_ptr) |
7e139075 RK |
5178 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
5179 | ||
ba3ad5e0 PDM |
5180 | /* If we have a sign-extension of a zero-extended value, we can |
5181 | replace that by a single zero-extension. */ | |
5182 | if (inside_int && inter_int && final_int | |
5183 | && inside_prec < inter_prec && inter_prec < final_prec | |
5184 | && inside_unsignedp && !inter_unsignedp) | |
5185 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
5186 | ||
7e139075 RK |
5187 | /* Two conversions in a row are not needed unless: |
5188 | - some conversion is floating-point (overstrict for now), or | |
5189 | - the intermediate type is narrower than both initial and | |
5190 | final, or | |
5191 | - the intermediate type and innermost type differ in signedness, | |
5192 | and the outermost type is wider than the intermediate, or | |
5193 | - the initial type is a pointer type and the precisions of the | |
5194 | intermediate and final types differ, or | |
b6cc0a72 | 5195 | - the final type is a pointer type and the precisions of the |
7e139075 RK |
5196 | initial and intermediate types differ. */ |
5197 | if (! inside_float && ! inter_float && ! final_float | |
5198 | && (inter_prec > inside_prec || inter_prec > final_prec) | |
5199 | && ! (inside_int && inter_int | |
5200 | && inter_unsignedp != inside_unsignedp | |
5201 | && inter_prec < final_prec) | |
5202 | && ((inter_unsignedp && inter_prec > inside_prec) | |
5203 | == (final_unsignedp && final_prec > inter_prec)) | |
5204 | && ! (inside_ptr && inter_prec != final_prec) | |
410d3f5d RK |
5205 | && ! (final_ptr && inside_prec != inter_prec) |
5206 | && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type)) | |
5207 | && TYPE_MODE (final_type) == TYPE_MODE (inter_type)) | |
5208 | && ! final_ptr) | |
7e139075 RK |
5209 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
5210 | } | |
6d716ca8 RS |
5211 | |
5212 | if (TREE_CODE (TREE_OPERAND (t, 0)) == MODIFY_EXPR | |
d8f6dbb9 RS |
5213 | && TREE_CONSTANT (TREE_OPERAND (TREE_OPERAND (t, 0), 1)) |
5214 | /* Detect assigning a bitfield. */ | |
5215 | && !(TREE_CODE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)) == COMPONENT_REF | |
5216 | && DECL_BIT_FIELD (TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (t, 0), 0), 1)))) | |
6d716ca8 | 5217 | { |
d8f6dbb9 | 5218 | /* Don't leave an assignment inside a conversion |
f72aed24 | 5219 | unless assigning a bitfield. */ |
6d716ca8 RS |
5220 | tree prev = TREE_OPERAND (t, 0); |
5221 | TREE_OPERAND (t, 0) = TREE_OPERAND (prev, 1); | |
5222 | /* First do the assignment, then return converted constant. */ | |
5223 | t = build (COMPOUND_EXPR, TREE_TYPE (t), prev, fold (t)); | |
5224 | TREE_USED (t) = 1; | |
5225 | return t; | |
5226 | } | |
5227 | if (!wins) | |
5228 | { | |
5229 | TREE_CONSTANT (t) = TREE_CONSTANT (arg0); | |
5230 | return t; | |
5231 | } | |
5232 | return fold_convert (t, arg0); | |
5233 | ||
5234 | #if 0 /* This loses on &"foo"[0]. */ | |
5235 | case ARRAY_REF: | |
5236 | { | |
5237 | int i; | |
5238 | ||
5239 | /* Fold an expression like: "foo"[2] */ | |
5240 | if (TREE_CODE (arg0) == STRING_CST | |
5241 | && TREE_CODE (arg1) == INTEGER_CST | |
05bccae2 | 5242 | && compare_tree_int (arg1, TREE_STRING_LENGTH (arg0)) < 0) |
6d716ca8 | 5243 | { |
05bccae2 | 5244 | t = build_int_2 (TREE_STRING_POINTER (arg0)[TREE_INT_CST_LOW (arg))], 0); |
6d716ca8 | 5245 | TREE_TYPE (t) = TREE_TYPE (TREE_TYPE (arg0)); |
ef2bf0c0 | 5246 | force_fit_type (t, 0); |
6d716ca8 RS |
5247 | } |
5248 | } | |
5249 | return t; | |
5250 | #endif /* 0 */ | |
5251 | ||
e082358b JM |
5252 | case COMPONENT_REF: |
5253 | if (TREE_CODE (arg0) == CONSTRUCTOR) | |
3ac4f0e6 JM |
5254 | { |
5255 | tree m = purpose_member (arg1, CONSTRUCTOR_ELTS (arg0)); | |
5256 | if (m) | |
5257 | t = TREE_VALUE (m); | |
5258 | } | |
e082358b JM |
5259 | return t; |
5260 | ||
6d716ca8 RS |
5261 | case RANGE_EXPR: |
5262 | TREE_CONSTANT (t) = wins; | |
5263 | return t; | |
5264 | ||
5265 | case NEGATE_EXPR: | |
5266 | if (wins) | |
5267 | { | |
5268 | if (TREE_CODE (arg0) == INTEGER_CST) | |
5269 | { | |
f9e158c3 JM |
5270 | unsigned HOST_WIDE_INT low; |
5271 | HOST_WIDE_INT high; | |
fe3e8e40 RS |
5272 | int overflow = neg_double (TREE_INT_CST_LOW (arg0), |
5273 | TREE_INT_CST_HIGH (arg0), | |
5274 | &low, &high); | |
5275 | t = build_int_2 (low, high); | |
6d716ca8 | 5276 | TREE_TYPE (t) = type; |
dc3907c5 PE |
5277 | TREE_OVERFLOW (t) |
5278 | = (TREE_OVERFLOW (arg0) | |
0c9cabe7 | 5279 | | force_fit_type (t, overflow && !TREE_UNSIGNED (type))); |
dc3907c5 PE |
5280 | TREE_CONSTANT_OVERFLOW (t) |
5281 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0); | |
6d716ca8 RS |
5282 | } |
5283 | else if (TREE_CODE (arg0) == REAL_CST) | |
5284 | t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0))); | |
6d716ca8 RS |
5285 | } |
5286 | else if (TREE_CODE (arg0) == NEGATE_EXPR) | |
5287 | return TREE_OPERAND (arg0, 0); | |
5288 | ||
5289 | /* Convert - (a - b) to (b - a) for non-floating-point. */ | |
1baa375f | 5290 | else if (TREE_CODE (arg0) == MINUS_EXPR |
de6c5979 | 5291 | && (! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations)) |
6d716ca8 RS |
5292 | return build (MINUS_EXPR, type, TREE_OPERAND (arg0, 1), |
5293 | TREE_OPERAND (arg0, 0)); | |
5294 | ||
5295 | return t; | |
5296 | ||
5297 | case ABS_EXPR: | |
5298 | if (wins) | |
5299 | { | |
5300 | if (TREE_CODE (arg0) == INTEGER_CST) | |
5301 | { | |
68e568c2 MM |
5302 | /* If the value is unsigned, then the absolute value is |
5303 | the same as the ordinary value. */ | |
5304 | if (TREE_UNSIGNED (type)) | |
5305 | return arg0; | |
5306 | /* Similarly, if the value is non-negative. */ | |
5307 | else if (INT_CST_LT (integer_minus_one_node, arg0)) | |
5308 | return arg0; | |
5309 | /* If the value is negative, then the absolute value is | |
5310 | its negation. */ | |
5311 | else | |
6d716ca8 | 5312 | { |
f9e158c3 JM |
5313 | unsigned HOST_WIDE_INT low; |
5314 | HOST_WIDE_INT high; | |
2a23183e RS |
5315 | int overflow = neg_double (TREE_INT_CST_LOW (arg0), |
5316 | TREE_INT_CST_HIGH (arg0), | |
5317 | &low, &high); | |
5318 | t = build_int_2 (low, high); | |
5319 | TREE_TYPE (t) = type; | |
dc3907c5 PE |
5320 | TREE_OVERFLOW (t) |
5321 | = (TREE_OVERFLOW (arg0) | |
e0f776fb | 5322 | | force_fit_type (t, overflow)); |
dc3907c5 PE |
5323 | TREE_CONSTANT_OVERFLOW (t) |
5324 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0); | |
6d716ca8 RS |
5325 | } |
5326 | } | |
5327 | else if (TREE_CODE (arg0) == REAL_CST) | |
5328 | { | |
c05a9b68 | 5329 | if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0))) |
6d716ca8 RS |
5330 | t = build_real (type, |
5331 | REAL_VALUE_NEGATE (TREE_REAL_CST (arg0))); | |
5332 | } | |
6d716ca8 RS |
5333 | } |
5334 | else if (TREE_CODE (arg0) == ABS_EXPR || TREE_CODE (arg0) == NEGATE_EXPR) | |
5335 | return build1 (ABS_EXPR, type, TREE_OPERAND (arg0, 0)); | |
5336 | return t; | |
5337 | ||
551064b1 RS |
5338 | case CONJ_EXPR: |
5339 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) | |
13eb1f7f | 5340 | return convert (type, arg0); |
551064b1 | 5341 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) |
c9869b75 | 5342 | return build (COMPLEX_EXPR, type, |
551064b1 | 5343 | TREE_OPERAND (arg0, 0), |
1baa375f | 5344 | negate_expr (TREE_OPERAND (arg0, 1))); |
551064b1 | 5345 | else if (TREE_CODE (arg0) == COMPLEX_CST) |
32812a40 JM |
5346 | return build_complex (type, TREE_REALPART (arg0), |
5347 | negate_expr (TREE_IMAGPART (arg0))); | |
551064b1 RS |
5348 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) |
5349 | return fold (build (TREE_CODE (arg0), type, | |
5350 | fold (build1 (CONJ_EXPR, type, | |
5351 | TREE_OPERAND (arg0, 0))), | |
5352 | fold (build1 (CONJ_EXPR, | |
5353 | type, TREE_OPERAND (arg0, 1))))); | |
5354 | else if (TREE_CODE (arg0) == CONJ_EXPR) | |
5355 | return TREE_OPERAND (arg0, 0); | |
5356 | return t; | |
5357 | ||
6d716ca8 RS |
5358 | case BIT_NOT_EXPR: |
5359 | if (wins) | |
5360 | { | |
380ff34a RK |
5361 | t = build_int_2 (~ TREE_INT_CST_LOW (arg0), |
5362 | ~ TREE_INT_CST_HIGH (arg0)); | |
6d716ca8 | 5363 | TREE_TYPE (t) = type; |
e0f776fb | 5364 | force_fit_type (t, 0); |
dc3907c5 | 5365 | TREE_OVERFLOW (t) = TREE_OVERFLOW (arg0); |
fe3e8e40 | 5366 | TREE_CONSTANT_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (arg0); |
6d716ca8 RS |
5367 | } |
5368 | else if (TREE_CODE (arg0) == BIT_NOT_EXPR) | |
5369 | return TREE_OPERAND (arg0, 0); | |
5370 | return t; | |
5371 | ||
5372 | case PLUS_EXPR: | |
5373 | /* A + (-B) -> A - B */ | |
5374 | if (TREE_CODE (arg1) == NEGATE_EXPR) | |
5375 | return fold (build (MINUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0))); | |
10414089 JL |
5376 | /* (-A) + B -> B - A */ |
5377 | if (TREE_CODE (arg0) == NEGATE_EXPR) | |
5378 | return fold (build (MINUS_EXPR, type, arg1, TREE_OPERAND (arg0, 0))); | |
7178e3af | 5379 | else if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
5380 | { |
5381 | if (integer_zerop (arg1)) | |
5382 | return non_lvalue (convert (type, arg0)); | |
5383 | ||
5384 | /* If we are adding two BIT_AND_EXPR's, both of which are and'ing | |
5385 | with a constant, and the two constants have no bits in common, | |
5386 | we should treat this as a BIT_IOR_EXPR since this may produce more | |
5387 | simplifications. */ | |
5388 | if (TREE_CODE (arg0) == BIT_AND_EXPR | |
5389 | && TREE_CODE (arg1) == BIT_AND_EXPR | |
5390 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
5391 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST | |
5392 | && integer_zerop (const_binop (BIT_AND_EXPR, | |
5393 | TREE_OPERAND (arg0, 1), | |
91d33e36 | 5394 | TREE_OPERAND (arg1, 1), 0))) |
6d716ca8 RS |
5395 | { |
5396 | code = BIT_IOR_EXPR; | |
5397 | goto bit_ior; | |
5398 | } | |
6a96fcb4 | 5399 | |
abe4f192 | 5400 | /* Reassociate (plus (plus (mult) (foo)) (mult)) as |
b6cc0a72 | 5401 | (plus (plus (mult) (mult)) (foo)) so that we can |
abe4f192 RH |
5402 | take advantage of the factoring cases below. */ |
5403 | if ((TREE_CODE (arg0) == PLUS_EXPR | |
5404 | && TREE_CODE (arg1) == MULT_EXPR) | |
5405 | || (TREE_CODE (arg1) == PLUS_EXPR | |
b6cc0a72 | 5406 | && TREE_CODE (arg0) == MULT_EXPR)) |
abe4f192 RH |
5407 | { |
5408 | tree parg0, parg1, parg, marg; | |
5409 | ||
5410 | if (TREE_CODE (arg0) == PLUS_EXPR) | |
5411 | parg = arg0, marg = arg1; | |
5412 | else | |
5413 | parg = arg1, marg = arg0; | |
5414 | parg0 = TREE_OPERAND (parg, 0); | |
5415 | parg1 = TREE_OPERAND (parg, 1); | |
5416 | STRIP_NOPS (parg0); | |
5417 | STRIP_NOPS (parg1); | |
5418 | ||
5419 | if (TREE_CODE (parg0) == MULT_EXPR | |
5420 | && TREE_CODE (parg1) != MULT_EXPR) | |
5421 | return fold (build (PLUS_EXPR, type, | |
5422 | fold (build (PLUS_EXPR, type, parg0, marg)), | |
5423 | parg1)); | |
5424 | if (TREE_CODE (parg0) != MULT_EXPR | |
5425 | && TREE_CODE (parg1) == MULT_EXPR) | |
5426 | return fold (build (PLUS_EXPR, type, | |
5427 | fold (build (PLUS_EXPR, type, parg1, marg)), | |
5428 | parg0)); | |
5429 | } | |
5430 | ||
45f97e2e RH |
5431 | if (TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (arg1) == MULT_EXPR) |
5432 | { | |
5433 | tree arg00, arg01, arg10, arg11; | |
07444f1d | 5434 | tree alt0 = NULL_TREE, alt1 = NULL_TREE, same; |
45f97e2e RH |
5435 | |
5436 | /* (A * C) + (B * C) -> (A+B) * C. | |
5437 | We are most concerned about the case where C is a constant, | |
5438 | but other combinations show up during loop reduction. Since | |
5439 | it is not difficult, try all four possibilities. */ | |
5440 | ||
5441 | arg00 = TREE_OPERAND (arg0, 0); | |
5442 | arg01 = TREE_OPERAND (arg0, 1); | |
5443 | arg10 = TREE_OPERAND (arg1, 0); | |
5444 | arg11 = TREE_OPERAND (arg1, 1); | |
5445 | same = NULL_TREE; | |
5446 | ||
5447 | if (operand_equal_p (arg01, arg11, 0)) | |
5448 | same = arg01, alt0 = arg00, alt1 = arg10; | |
5449 | else if (operand_equal_p (arg00, arg10, 0)) | |
5450 | same = arg00, alt0 = arg01, alt1 = arg11; | |
5451 | else if (operand_equal_p (arg00, arg11, 0)) | |
5452 | same = arg00, alt0 = arg01, alt1 = arg10; | |
5453 | else if (operand_equal_p (arg01, arg10, 0)) | |
5454 | same = arg01, alt0 = arg00, alt1 = arg11; | |
5455 | ||
abe4f192 RH |
5456 | /* No identical multiplicands; see if we can find a common |
5457 | power-of-two factor in non-power-of-two multiplies. This | |
5458 | can help in multi-dimensional array access. */ | |
5459 | else if (TREE_CODE (arg01) == INTEGER_CST | |
5460 | && TREE_CODE (arg11) == INTEGER_CST | |
5461 | && TREE_INT_CST_HIGH (arg01) == 0 | |
5462 | && TREE_INT_CST_HIGH (arg11) == 0) | |
5463 | { | |
5464 | HOST_WIDE_INT int01, int11, tmp; | |
5465 | int01 = TREE_INT_CST_LOW (arg01); | |
5466 | int11 = TREE_INT_CST_LOW (arg11); | |
5467 | ||
5468 | /* Move min of absolute values to int11. */ | |
5469 | if ((int01 >= 0 ? int01 : -int01) | |
5470 | < (int11 >= 0 ? int11 : -int11)) | |
5471 | { | |
5472 | tmp = int01, int01 = int11, int11 = tmp; | |
5473 | alt0 = arg00, arg00 = arg10, arg10 = alt0; | |
5474 | alt0 = arg01, arg01 = arg11, arg11 = alt0; | |
5475 | } | |
5476 | ||
5477 | if (exact_log2 (int11) > 0 && int01 % int11 == 0) | |
5478 | { | |
5479 | alt0 = fold (build (MULT_EXPR, type, arg00, | |
5480 | build_int_2 (int01 / int11, 0))); | |
5481 | alt1 = arg10; | |
5482 | same = arg11; | |
5483 | } | |
5484 | } | |
5485 | ||
45f97e2e | 5486 | if (same) |
b6cc0a72 | 5487 | return fold (build (MULT_EXPR, type, |
45f97e2e RH |
5488 | fold (build (PLUS_EXPR, type, alt0, alt1)), |
5489 | same)); | |
5490 | } | |
6d716ca8 RS |
5491 | } |
5492 | /* In IEEE floating point, x+0 may not equal x. */ | |
996c63d3 | 5493 | else if ((TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
de6c5979 | 5494 | || flag_unsafe_math_optimizations) |
6d716ca8 RS |
5495 | && real_zerop (arg1)) |
5496 | return non_lvalue (convert (type, arg0)); | |
10414089 | 5497 | /* x+(-0) equals x, even for IEEE. */ |
2af3e5fb AB |
5498 | else if (TREE_CODE (arg1) == REAL_CST |
5499 | && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (arg1))) | |
10414089 JL |
5500 | return non_lvalue (convert (type, arg0)); |
5501 | ||
79e8185c JH |
5502 | bit_rotate: |
5503 | /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A | |
5504 | is a rotate of A by C1 bits. */ | |
5505 | /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A | |
5506 | is a rotate of A by B bits. */ | |
5507 | { | |
b6cc0a72 KH |
5508 | register enum tree_code code0, code1; |
5509 | code0 = TREE_CODE (arg0); | |
5510 | code1 = TREE_CODE (arg1); | |
5511 | if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR) | |
5512 | || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR)) | |
79e8185c | 5513 | && operand_equal_p (TREE_OPERAND (arg0, 0), |
b6cc0a72 | 5514 | TREE_OPERAND (arg1, 0), 0) |
79e8185c JH |
5515 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))) |
5516 | { | |
5517 | register tree tree01, tree11; | |
5518 | register enum tree_code code01, code11; | |
5519 | ||
5520 | tree01 = TREE_OPERAND (arg0, 1); | |
5521 | tree11 = TREE_OPERAND (arg1, 1); | |
5522 | STRIP_NOPS (tree01); | |
5523 | STRIP_NOPS (tree11); | |
5524 | code01 = TREE_CODE (tree01); | |
5525 | code11 = TREE_CODE (tree11); | |
5526 | if (code01 == INTEGER_CST | |
b6cc0a72 KH |
5527 | && code11 == INTEGER_CST |
5528 | && TREE_INT_CST_HIGH (tree01) == 0 | |
5529 | && TREE_INT_CST_HIGH (tree11) == 0 | |
5530 | && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11)) | |
5531 | == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))))) | |
79e8185c | 5532 | return build (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0), |
b6cc0a72 | 5533 | code0 == LSHIFT_EXPR ? tree01 : tree11); |
79e8185c JH |
5534 | else if (code11 == MINUS_EXPR) |
5535 | { | |
b6cc0a72 KH |
5536 | tree tree110, tree111; |
5537 | tree110 = TREE_OPERAND (tree11, 0); | |
5538 | tree111 = TREE_OPERAND (tree11, 1); | |
5539 | STRIP_NOPS (tree110); | |
5540 | STRIP_NOPS (tree111); | |
5541 | if (TREE_CODE (tree110) == INTEGER_CST | |
05bccae2 RK |
5542 | && 0 == compare_tree_int (tree110, |
5543 | TYPE_PRECISION | |
5544 | (TREE_TYPE (TREE_OPERAND | |
5545 | (arg0, 0)))) | |
79e8185c | 5546 | && operand_equal_p (tree01, tree111, 0)) |
b6cc0a72 KH |
5547 | return build ((code0 == LSHIFT_EXPR |
5548 | ? LROTATE_EXPR | |
5549 | : RROTATE_EXPR), | |
5550 | type, TREE_OPERAND (arg0, 0), tree01); | |
79e8185c JH |
5551 | } |
5552 | else if (code01 == MINUS_EXPR) | |
5553 | { | |
b6cc0a72 KH |
5554 | tree tree010, tree011; |
5555 | tree010 = TREE_OPERAND (tree01, 0); | |
5556 | tree011 = TREE_OPERAND (tree01, 1); | |
5557 | STRIP_NOPS (tree010); | |
5558 | STRIP_NOPS (tree011); | |
5559 | if (TREE_CODE (tree010) == INTEGER_CST | |
05bccae2 RK |
5560 | && 0 == compare_tree_int (tree010, |
5561 | TYPE_PRECISION | |
5562 | (TREE_TYPE (TREE_OPERAND | |
5563 | (arg0, 0)))) | |
79e8185c | 5564 | && operand_equal_p (tree11, tree011, 0)) |
b6cc0a72 KH |
5565 | return build ((code0 != LSHIFT_EXPR |
5566 | ? LROTATE_EXPR | |
5567 | : RROTATE_EXPR), | |
5568 | type, TREE_OPERAND (arg0, 0), tree11); | |
79e8185c JH |
5569 | } |
5570 | } | |
5571 | } | |
10414089 | 5572 | |
6d716ca8 | 5573 | associate: |
1baa375f RK |
5574 | /* In most languages, can't associate operations on floats through |
5575 | parentheses. Rather than remember where the parentheses were, we | |
5576 | don't associate floats at all. It shouldn't matter much. However, | |
5577 | associating multiplications is only very slightly inaccurate, so do | |
de6c5979 | 5578 | that if -funsafe-math-optimizations is specified. */ |
1baa375f RK |
5579 | |
5580 | if (! wins | |
5581 | && (! FLOAT_TYPE_P (type) | |
de6c5979 | 5582 | || (flag_unsafe_math_optimizations && code == MULT_EXPR))) |
6d716ca8 | 5583 | { |
1baa375f RK |
5584 | tree var0, con0, lit0, var1, con1, lit1; |
5585 | ||
5586 | /* Split both trees into variables, constants, and literals. Then | |
5587 | associate each group together, the constants with literals, | |
5588 | then the result with variables. This increases the chances of | |
5589 | literals being recombined later and of generating relocatable | |
30f7a378 | 5590 | expressions for the sum of a constant and literal. */ |
1baa375f RK |
5591 | var0 = split_tree (arg0, code, &con0, &lit0, 0); |
5592 | var1 = split_tree (arg1, code, &con1, &lit1, code == MINUS_EXPR); | |
5593 | ||
5594 | /* Only do something if we found more than two objects. Otherwise, | |
5595 | nothing has changed and we risk infinite recursion. */ | |
5596 | if (2 < ((var0 != 0) + (var1 != 0) + (con0 != 0) + (con1 != 0) | |
5597 | + (lit0 != 0) + (lit1 != 0))) | |
6d716ca8 | 5598 | { |
1baa375f RK |
5599 | var0 = associate_trees (var0, var1, code, type); |
5600 | con0 = associate_trees (con0, con1, code, type); | |
5601 | lit0 = associate_trees (lit0, lit1, code, type); | |
5602 | con0 = associate_trees (con0, lit0, code, type); | |
5603 | return convert (type, associate_trees (var0, con0, code, type)); | |
6d716ca8 RS |
5604 | } |
5605 | } | |
1baa375f | 5606 | |
6d716ca8 RS |
5607 | binary: |
5608 | #if defined (REAL_IS_NOT_DOUBLE) && ! defined (REAL_ARITHMETIC) | |
5609 | if (TREE_CODE (arg1) == REAL_CST) | |
5610 | return t; | |
5611 | #endif /* REAL_IS_NOT_DOUBLE, and no REAL_ARITHMETIC */ | |
5612 | if (wins) | |
91d33e36 | 5613 | t1 = const_binop (code, arg0, arg1, 0); |
6d716ca8 RS |
5614 | if (t1 != NULL_TREE) |
5615 | { | |
5616 | /* The return value should always have | |
5617 | the same type as the original expression. */ | |
380ff34a RK |
5618 | if (TREE_TYPE (t1) != TREE_TYPE (t)) |
5619 | t1 = convert (TREE_TYPE (t), t1); | |
5620 | ||
6d716ca8 RS |
5621 | return t1; |
5622 | } | |
5623 | return t; | |
5624 | ||
5625 | case MINUS_EXPR: | |
10414089 JL |
5626 | /* A - (-B) -> A + B */ |
5627 | if (TREE_CODE (arg1) == NEGATE_EXPR) | |
5628 | return fold (build (PLUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0))); | |
5629 | /* (-A) - CST -> (-CST) - A for floating point (what about ints ?) */ | |
5630 | if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == REAL_CST) | |
5631 | return | |
b6cc0a72 | 5632 | fold (build (MINUS_EXPR, type, |
10414089 JL |
5633 | build_real (TREE_TYPE (arg1), |
5634 | REAL_VALUE_NEGATE (TREE_REAL_CST (arg1))), | |
5635 | TREE_OPERAND (arg0, 0))); | |
5636 | ||
7178e3af | 5637 | if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
5638 | { |
5639 | if (! wins && integer_zerop (arg0)) | |
b8fbe62c | 5640 | return negate_expr (convert (type, arg1)); |
6d716ca8 RS |
5641 | if (integer_zerop (arg1)) |
5642 | return non_lvalue (convert (type, arg0)); | |
6a96fcb4 RK |
5643 | |
5644 | /* (A * C) - (B * C) -> (A-B) * C. Since we are most concerned | |
5645 | about the case where C is a constant, just try one of the | |
5646 | four possibilities. */ | |
5647 | ||
5648 | if (TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (arg1) == MULT_EXPR | |
5649 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
5650 | TREE_OPERAND (arg1, 1), 0)) | |
5651 | return fold (build (MULT_EXPR, type, | |
5652 | fold (build (MINUS_EXPR, type, | |
5653 | TREE_OPERAND (arg0, 0), | |
5654 | TREE_OPERAND (arg1, 0))), | |
5655 | TREE_OPERAND (arg0, 1))); | |
6d716ca8 | 5656 | } |
fab446b8 RK |
5657 | |
5658 | else if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT | |
de6c5979 | 5659 | || flag_unsafe_math_optimizations) |
6d716ca8 | 5660 | { |
c05a9b68 | 5661 | /* Except with IEEE floating point, 0-x equals -x. */ |
6d716ca8 | 5662 | if (! wins && real_zerop (arg0)) |
b8fbe62c | 5663 | return negate_expr (convert (type, arg1)); |
c05a9b68 RS |
5664 | /* Except with IEEE floating point, x-0 equals x. */ |
5665 | if (real_zerop (arg1)) | |
6d716ca8 | 5666 | return non_lvalue (convert (type, arg0)); |
fab446b8 | 5667 | } |
a6acbe15 | 5668 | |
b6cc0a72 | 5669 | /* Fold &x - &x. This can happen from &x.foo - &x. |
fab446b8 RK |
5670 | This is unsafe for certain floats even in non-IEEE formats. |
5671 | In IEEE, it is unsafe because it does wrong for NaNs. | |
5672 | Also note that operand_equal_p is always false if an operand | |
5673 | is volatile. */ | |
5674 | ||
de6c5979 | 5675 | if ((! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations) |
59d90212 | 5676 | && operand_equal_p (arg0, arg1, 0)) |
fab446b8 | 5677 | return convert (type, integer_zero_node); |
a6acbe15 | 5678 | |
6d716ca8 RS |
5679 | goto associate; |
5680 | ||
5681 | case MULT_EXPR: | |
10414089 JL |
5682 | /* (-A) * (-B) -> A * B */ |
5683 | if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == NEGATE_EXPR) | |
5684 | return fold (build (MULT_EXPR, type, TREE_OPERAND (arg0, 0), | |
b6cc0a72 | 5685 | TREE_OPERAND (arg1, 0))); |
10414089 | 5686 | |
7178e3af | 5687 | if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
5688 | { |
5689 | if (integer_zerop (arg1)) | |
5690 | return omit_one_operand (type, arg1, arg0); | |
5691 | if (integer_onep (arg1)) | |
5692 | return non_lvalue (convert (type, arg0)); | |
5693 | ||
5694 | /* (a * (1 << b)) is (a << b) */ | |
5695 | if (TREE_CODE (arg1) == LSHIFT_EXPR | |
5696 | && integer_onep (TREE_OPERAND (arg1, 0))) | |
5697 | return fold (build (LSHIFT_EXPR, type, arg0, | |
5698 | TREE_OPERAND (arg1, 1))); | |
5699 | if (TREE_CODE (arg0) == LSHIFT_EXPR | |
5700 | && integer_onep (TREE_OPERAND (arg0, 0))) | |
5701 | return fold (build (LSHIFT_EXPR, type, arg1, | |
5702 | TREE_OPERAND (arg0, 1))); | |
1baa375f RK |
5703 | |
5704 | if (TREE_CODE (arg1) == INTEGER_CST | |
5705 | && 0 != (tem = extract_muldiv (TREE_OPERAND (t, 0), arg1, | |
5706 | code, NULL_TREE))) | |
5707 | return convert (type, tem); | |
5708 | ||
6d716ca8 | 5709 | } |
6d716ca8 RS |
5710 | else |
5711 | { | |
c05a9b68 | 5712 | /* x*0 is 0, except for IEEE floating point. */ |
fab446b8 | 5713 | if ((TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
de6c5979 | 5714 | || flag_unsafe_math_optimizations) |
6d716ca8 RS |
5715 | && real_zerop (arg1)) |
5716 | return omit_one_operand (type, arg1, arg0); | |
c05a9b68 | 5717 | /* In IEEE floating point, x*1 is not equivalent to x for snans. |
6d716ca8 RS |
5718 | However, ANSI says we can drop signals, |
5719 | so we can do this anyway. */ | |
5720 | if (real_onep (arg1)) | |
5721 | return non_lvalue (convert (type, arg0)); | |
5722 | /* x*2 is x+x */ | |
c5c76735 | 5723 | if (! wins && real_twop (arg1) && global_bindings_p () == 0 |
9ec36da5 | 5724 | && ! contains_placeholder_p (arg0)) |
6d716ca8 RS |
5725 | { |
5726 | tree arg = save_expr (arg0); | |
5727 | return build (PLUS_EXPR, type, arg, arg); | |
5728 | } | |
5729 | } | |
5730 | goto associate; | |
5731 | ||
5732 | case BIT_IOR_EXPR: | |
5733 | bit_ior: | |
5734 | if (integer_all_onesp (arg1)) | |
5735 | return omit_one_operand (type, arg1, arg0); | |
5736 | if (integer_zerop (arg1)) | |
5737 | return non_lvalue (convert (type, arg0)); | |
5738 | t1 = distribute_bit_expr (code, type, arg0, arg1); | |
5739 | if (t1 != NULL_TREE) | |
5740 | return t1; | |
85d2e16c | 5741 | |
ccc5fd95 JH |
5742 | /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))). |
5743 | ||
b6cc0a72 | 5744 | This results in more efficient code for machines without a NAND |
ccc5fd95 JH |
5745 | instruction. Combine will canonicalize to the first form |
5746 | which will allow use of NAND instructions provided by the | |
5747 | backend if they exist. */ | |
5748 | if (TREE_CODE (arg0) == BIT_NOT_EXPR | |
5749 | && TREE_CODE (arg1) == BIT_NOT_EXPR) | |
5750 | { | |
5751 | return fold (build1 (BIT_NOT_EXPR, type, | |
5752 | build (BIT_AND_EXPR, type, | |
5753 | TREE_OPERAND (arg0, 0), | |
5754 | TREE_OPERAND (arg1, 0)))); | |
5755 | } | |
5756 | ||
79e8185c JH |
5757 | /* See if this can be simplified into a rotate first. If that |
5758 | is unsuccessful continue in the association code. */ | |
5759 | goto bit_rotate; | |
6d716ca8 RS |
5760 | |
5761 | case BIT_XOR_EXPR: | |
5762 | if (integer_zerop (arg1)) | |
5763 | return non_lvalue (convert (type, arg0)); | |
5764 | if (integer_all_onesp (arg1)) | |
5765 | return fold (build1 (BIT_NOT_EXPR, type, arg0)); | |
79e8185c JH |
5766 | |
5767 | /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing | |
5768 | with a constant, and the two constants have no bits in common, | |
5769 | we should treat this as a BIT_IOR_EXPR since this may produce more | |
5770 | simplifications. */ | |
5771 | if (TREE_CODE (arg0) == BIT_AND_EXPR | |
5772 | && TREE_CODE (arg1) == BIT_AND_EXPR | |
5773 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
5774 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST | |
5775 | && integer_zerop (const_binop (BIT_AND_EXPR, | |
5776 | TREE_OPERAND (arg0, 1), | |
5777 | TREE_OPERAND (arg1, 1), 0))) | |
b6cc0a72 KH |
5778 | { |
5779 | code = BIT_IOR_EXPR; | |
5780 | goto bit_ior; | |
5781 | } | |
79e8185c | 5782 | |
03e0a65f | 5783 | /* See if this can be simplified into a rotate first. If that |
79e8185c | 5784 | is unsuccessful continue in the association code. */ |
03e0a65f | 5785 | goto bit_rotate; |
6d716ca8 RS |
5786 | |
5787 | case BIT_AND_EXPR: | |
5788 | bit_and: | |
5789 | if (integer_all_onesp (arg1)) | |
5790 | return non_lvalue (convert (type, arg0)); | |
5791 | if (integer_zerop (arg1)) | |
5792 | return omit_one_operand (type, arg1, arg0); | |
5793 | t1 = distribute_bit_expr (code, type, arg0, arg1); | |
5794 | if (t1 != NULL_TREE) | |
5795 | return t1; | |
5796 | /* Simplify ((int)c & 0x377) into (int)c, if c is unsigned char. */ | |
5797 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == NOP_EXPR | |
5798 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg1, 0)))) | |
5799 | { | |
770ae6cc RK |
5800 | unsigned int prec |
5801 | = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg1, 0))); | |
5802 | ||
906c4e36 RK |
5803 | if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT |
5804 | && (~TREE_INT_CST_LOW (arg0) | |
5805 | & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0) | |
6d716ca8 RS |
5806 | return build1 (NOP_EXPR, type, TREE_OPERAND (arg1, 0)); |
5807 | } | |
5808 | if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR | |
5809 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))) | |
5810 | { | |
770ae6cc RK |
5811 | unsigned int prec |
5812 | = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))); | |
5813 | ||
906c4e36 RK |
5814 | if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT |
5815 | && (~TREE_INT_CST_LOW (arg1) | |
5816 | & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0) | |
6d716ca8 RS |
5817 | return build1 (NOP_EXPR, type, TREE_OPERAND (arg0, 0)); |
5818 | } | |
ccc5fd95 | 5819 | |
a36335da | 5820 | /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))). |
ccc5fd95 | 5821 | |
b6cc0a72 | 5822 | This results in more efficient code for machines without a NOR |
ccc5fd95 JH |
5823 | instruction. Combine will canonicalize to the first form |
5824 | which will allow use of NOR instructions provided by the | |
5825 | backend if they exist. */ | |
5826 | if (TREE_CODE (arg0) == BIT_NOT_EXPR | |
5827 | && TREE_CODE (arg1) == BIT_NOT_EXPR) | |
5828 | { | |
5829 | return fold (build1 (BIT_NOT_EXPR, type, | |
5830 | build (BIT_IOR_EXPR, type, | |
5831 | TREE_OPERAND (arg0, 0), | |
5832 | TREE_OPERAND (arg1, 0)))); | |
5833 | } | |
5834 | ||
6d716ca8 RS |
5835 | goto associate; |
5836 | ||
5837 | case BIT_ANDTC_EXPR: | |
5838 | if (integer_all_onesp (arg0)) | |
5839 | return non_lvalue (convert (type, arg1)); | |
5840 | if (integer_zerop (arg0)) | |
5841 | return omit_one_operand (type, arg0, arg1); | |
5842 | if (TREE_CODE (arg1) == INTEGER_CST) | |
5843 | { | |
5844 | arg1 = fold (build1 (BIT_NOT_EXPR, type, arg1)); | |
5845 | code = BIT_AND_EXPR; | |
5846 | goto bit_and; | |
5847 | } | |
5848 | goto binary; | |
5849 | ||
e9aaa5a5 RK |
5850 | case RDIV_EXPR: |
5851 | /* In most cases, do nothing with a divide by zero. */ | |
5852 | #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) | |
5853 | #ifndef REAL_INFINITY | |
5854 | if (TREE_CODE (arg1) == REAL_CST && real_zerop (arg1)) | |
5855 | return t; | |
5856 | #endif | |
5857 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
5858 | ||
10414089 JL |
5859 | /* (-A) / (-B) -> A / B */ |
5860 | if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == NEGATE_EXPR) | |
5861 | return fold (build (RDIV_EXPR, type, TREE_OPERAND (arg0, 0), | |
5862 | TREE_OPERAND (arg1, 0))); | |
5863 | ||
e9aaa5a5 RK |
5864 | /* In IEEE floating point, x/1 is not equivalent to x for snans. |
5865 | However, ANSI says we can drop signals, so we can do this anyway. */ | |
5866 | if (real_onep (arg1)) | |
5867 | return non_lvalue (convert (type, arg0)); | |
5868 | ||
5869 | /* If ARG1 is a constant, we can convert this to a multiply by the | |
5870 | reciprocal. This does not have the same rounding properties, | |
de6c5979 BL |
5871 | so only do this if -funsafe-math-optimizations. We can actually |
5872 | always safely do it if ARG1 is a power of two, but it's hard to | |
5873 | tell if it is or not in a portable manner. */ | |
39647dcb RK |
5874 | if (TREE_CODE (arg1) == REAL_CST) |
5875 | { | |
de6c5979 | 5876 | if (flag_unsafe_math_optimizations |
39647dcb RK |
5877 | && 0 != (tem = const_binop (code, build_real (type, dconst1), |
5878 | arg1, 0))) | |
5879 | return fold (build (MULT_EXPR, type, arg0, tem)); | |
30f7a378 | 5880 | /* Find the reciprocal if optimizing and the result is exact. */ |
39647dcb RK |
5881 | else if (optimize) |
5882 | { | |
5883 | REAL_VALUE_TYPE r; | |
5884 | r = TREE_REAL_CST (arg1); | |
5885 | if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r)) | |
b6cc0a72 KH |
5886 | { |
5887 | tem = build_real (type, r); | |
5888 | return fold (build (MULT_EXPR, type, arg0, tem)); | |
5889 | } | |
39647dcb RK |
5890 | } |
5891 | } | |
bc8d3f91 JH |
5892 | /* Convert A/B/C to A/(B*C). */ |
5893 | if (flag_unsafe_math_optimizations | |
5894 | && TREE_CODE (arg0) == RDIV_EXPR) | |
5895 | { | |
5896 | return fold (build (RDIV_EXPR, type, TREE_OPERAND (arg0, 0), | |
5897 | build (MULT_EXPR, type, TREE_OPERAND (arg0, 1), | |
5898 | arg1))); | |
5899 | } | |
5900 | /* Convert A/(B/C) to (A/B)*C. */ | |
5901 | if (flag_unsafe_math_optimizations | |
5902 | && TREE_CODE (arg1) == RDIV_EXPR) | |
5903 | { | |
5904 | return fold (build (MULT_EXPR, type, | |
5905 | build (RDIV_EXPR, type, arg0, | |
5906 | TREE_OPERAND (arg1, 0)), | |
5907 | TREE_OPERAND (arg1, 1))); | |
5908 | } | |
e9aaa5a5 RK |
5909 | goto binary; |
5910 | ||
6d716ca8 RS |
5911 | case TRUNC_DIV_EXPR: |
5912 | case ROUND_DIV_EXPR: | |
5913 | case FLOOR_DIV_EXPR: | |
5914 | case CEIL_DIV_EXPR: | |
5915 | case EXACT_DIV_EXPR: | |
6d716ca8 RS |
5916 | if (integer_onep (arg1)) |
5917 | return non_lvalue (convert (type, arg0)); | |
5918 | if (integer_zerop (arg1)) | |
5919 | return t; | |
3b998c11 | 5920 | |
39dfb55a JL |
5921 | /* If arg0 is a multiple of arg1, then rewrite to the fastest div |
5922 | operation, EXACT_DIV_EXPR. | |
5923 | ||
91585c63 TM |
5924 | Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now. |
5925 | At one time others generated faster code, it's not clear if they do | |
5926 | after the last round to changes to the DIV code in expmed.c. */ | |
5927 | if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR) | |
39dfb55a JL |
5928 | && multiple_of_p (type, arg0, arg1)) |
5929 | return fold (build (EXACT_DIV_EXPR, type, arg0, arg1)); | |
5930 | ||
b6cc0a72 | 5931 | if (TREE_CODE (arg1) == INTEGER_CST |
1baa375f RK |
5932 | && 0 != (tem = extract_muldiv (TREE_OPERAND (t, 0), arg1, |
5933 | code, NULL_TREE))) | |
5934 | return convert (type, tem); | |
3b998c11 | 5935 | |
6d716ca8 RS |
5936 | goto binary; |
5937 | ||
5938 | case CEIL_MOD_EXPR: | |
5939 | case FLOOR_MOD_EXPR: | |
5940 | case ROUND_MOD_EXPR: | |
5941 | case TRUNC_MOD_EXPR: | |
5942 | if (integer_onep (arg1)) | |
5943 | return omit_one_operand (type, integer_zero_node, arg0); | |
5944 | if (integer_zerop (arg1)) | |
5945 | return t; | |
6a96fcb4 | 5946 | |
6a96fcb4 | 5947 | if (TREE_CODE (arg1) == INTEGER_CST |
1baa375f RK |
5948 | && 0 != (tem = extract_muldiv (TREE_OPERAND (t, 0), arg1, |
5949 | code, NULL_TREE))) | |
5950 | return convert (type, tem); | |
6a96fcb4 | 5951 | |
6d716ca8 RS |
5952 | goto binary; |
5953 | ||
5954 | case LSHIFT_EXPR: | |
5955 | case RSHIFT_EXPR: | |
5956 | case LROTATE_EXPR: | |
5957 | case RROTATE_EXPR: | |
5958 | if (integer_zerop (arg1)) | |
5959 | return non_lvalue (convert (type, arg0)); | |
5960 | /* Since negative shift count is not well-defined, | |
5961 | don't try to compute it in the compiler. */ | |
4d39710e | 5962 | if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0) |
6d716ca8 | 5963 | return t; |
4d39710e RK |
5964 | /* Rewrite an LROTATE_EXPR by a constant into an |
5965 | RROTATE_EXPR by a new constant. */ | |
5966 | if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST) | |
5967 | { | |
5968 | TREE_SET_CODE (t, RROTATE_EXPR); | |
5969 | code = RROTATE_EXPR; | |
5970 | TREE_OPERAND (t, 1) = arg1 | |
5971 | = const_binop | |
5972 | (MINUS_EXPR, | |
5973 | convert (TREE_TYPE (arg1), | |
5974 | build_int_2 (GET_MODE_BITSIZE (TYPE_MODE (type)), 0)), | |
5975 | arg1, 0); | |
5976 | if (tree_int_cst_sgn (arg1) < 0) | |
5977 | return t; | |
5978 | } | |
5979 | ||
5980 | /* If we have a rotate of a bit operation with the rotate count and | |
5981 | the second operand of the bit operation both constant, | |
5982 | permute the two operations. */ | |
5983 | if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
5984 | && (TREE_CODE (arg0) == BIT_AND_EXPR | |
5985 | || TREE_CODE (arg0) == BIT_ANDTC_EXPR | |
5986 | || TREE_CODE (arg0) == BIT_IOR_EXPR | |
5987 | || TREE_CODE (arg0) == BIT_XOR_EXPR) | |
5988 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
5989 | return fold (build (TREE_CODE (arg0), type, | |
5990 | fold (build (code, type, | |
5991 | TREE_OPERAND (arg0, 0), arg1)), | |
5992 | fold (build (code, type, | |
5993 | TREE_OPERAND (arg0, 1), arg1)))); | |
5994 | ||
5995 | /* Two consecutive rotates adding up to the width of the mode can | |
5996 | be ignored. */ | |
5997 | if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
5998 | && TREE_CODE (arg0) == RROTATE_EXPR | |
5999 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
6000 | && TREE_INT_CST_HIGH (arg1) == 0 | |
6001 | && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0 | |
6002 | && ((TREE_INT_CST_LOW (arg1) | |
6003 | + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))) | |
05bccae2 | 6004 | == (unsigned int) GET_MODE_BITSIZE (TYPE_MODE (type)))) |
4d39710e RK |
6005 | return TREE_OPERAND (arg0, 0); |
6006 | ||
6d716ca8 RS |
6007 | goto binary; |
6008 | ||
6009 | case MIN_EXPR: | |
6010 | if (operand_equal_p (arg0, arg1, 0)) | |
13eb1f7f | 6011 | return omit_one_operand (type, arg0, arg1); |
7178e3af | 6012 | if (INTEGRAL_TYPE_P (type) |
6d716ca8 RS |
6013 | && operand_equal_p (arg1, TYPE_MIN_VALUE (type), 1)) |
6014 | return omit_one_operand (type, arg1, arg0); | |
6015 | goto associate; | |
6016 | ||
6017 | case MAX_EXPR: | |
6018 | if (operand_equal_p (arg0, arg1, 0)) | |
13eb1f7f | 6019 | return omit_one_operand (type, arg0, arg1); |
7178e3af | 6020 | if (INTEGRAL_TYPE_P (type) |
e1ee5cdc | 6021 | && TYPE_MAX_VALUE (type) |
6d716ca8 RS |
6022 | && operand_equal_p (arg1, TYPE_MAX_VALUE (type), 1)) |
6023 | return omit_one_operand (type, arg1, arg0); | |
6024 | goto associate; | |
6025 | ||
6026 | case TRUTH_NOT_EXPR: | |
6027 | /* Note that the operand of this must be an int | |
6028 | and its values must be 0 or 1. | |
6029 | ("true" is a fixed value perhaps depending on the language, | |
6030 | but we don't handle values other than 1 correctly yet.) */ | |
1180eb10 JM |
6031 | tem = invert_truthvalue (arg0); |
6032 | /* Avoid infinite recursion. */ | |
6033 | if (TREE_CODE (tem) == TRUTH_NOT_EXPR) | |
6034 | return t; | |
6035 | return convert (type, tem); | |
6d716ca8 RS |
6036 | |
6037 | case TRUTH_ANDIF_EXPR: | |
6038 | /* Note that the operands of this must be ints | |
6039 | and their values must be 0 or 1. | |
6040 | ("true" is a fixed value perhaps depending on the language.) */ | |
6041 | /* If first arg is constant zero, return it. */ | |
772447c5 | 6042 | if (integer_zerop (arg0)) |
13eb1f7f | 6043 | return convert (type, arg0); |
6d716ca8 RS |
6044 | case TRUTH_AND_EXPR: |
6045 | /* If either arg is constant true, drop it. */ | |
6046 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
13eb1f7f | 6047 | return non_lvalue (convert (type, arg1)); |
235cfbc4 BS |
6048 | if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1) |
6049 | /* Preserve sequence points. */ | |
6050 | && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0))) | |
13eb1f7f | 6051 | return non_lvalue (convert (type, arg0)); |
772447c5 RK |
6052 | /* If second arg is constant zero, result is zero, but first arg |
6053 | must be evaluated. */ | |
6054 | if (integer_zerop (arg1)) | |
6055 | return omit_one_operand (type, arg1, arg0); | |
80906567 RK |
6056 | /* Likewise for first arg, but note that only the TRUTH_AND_EXPR |
6057 | case will be handled here. */ | |
6058 | if (integer_zerop (arg0)) | |
6059 | return omit_one_operand (type, arg0, arg1); | |
6d716ca8 RS |
6060 | |
6061 | truth_andor: | |
e9b5e15f RK |
6062 | /* We only do these simplifications if we are optimizing. */ |
6063 | if (!optimize) | |
6064 | return t; | |
6065 | ||
6066 | /* Check for things like (A || B) && (A || C). We can convert this | |
6067 | to A || (B && C). Note that either operator can be any of the four | |
6068 | truth and/or operations and the transformation will still be | |
6069 | valid. Also note that we only care about order for the | |
96f06cb6 | 6070 | ANDIF and ORIF operators. If B contains side effects, this |
30f7a378 | 6071 | might change the truth-value of A. */ |
e9b5e15f RK |
6072 | if (TREE_CODE (arg0) == TREE_CODE (arg1) |
6073 | && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR | |
6074 | || TREE_CODE (arg0) == TRUTH_ORIF_EXPR | |
6075 | || TREE_CODE (arg0) == TRUTH_AND_EXPR | |
96f06cb6 RK |
6076 | || TREE_CODE (arg0) == TRUTH_OR_EXPR) |
6077 | && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1))) | |
e9b5e15f RK |
6078 | { |
6079 | tree a00 = TREE_OPERAND (arg0, 0); | |
6080 | tree a01 = TREE_OPERAND (arg0, 1); | |
6081 | tree a10 = TREE_OPERAND (arg1, 0); | |
6082 | tree a11 = TREE_OPERAND (arg1, 1); | |
6083 | int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR | |
6084 | || TREE_CODE (arg0) == TRUTH_AND_EXPR) | |
6085 | && (code == TRUTH_AND_EXPR | |
6086 | || code == TRUTH_OR_EXPR)); | |
6087 | ||
6088 | if (operand_equal_p (a00, a10, 0)) | |
6089 | return fold (build (TREE_CODE (arg0), type, a00, | |
6090 | fold (build (code, type, a01, a11)))); | |
6091 | else if (commutative && operand_equal_p (a00, a11, 0)) | |
6092 | return fold (build (TREE_CODE (arg0), type, a00, | |
6093 | fold (build (code, type, a01, a10)))); | |
6094 | else if (commutative && operand_equal_p (a01, a10, 0)) | |
6095 | return fold (build (TREE_CODE (arg0), type, a01, | |
6096 | fold (build (code, type, a00, a11)))); | |
6097 | ||
6098 | /* This case if tricky because we must either have commutative | |
6099 | operators or else A10 must not have side-effects. */ | |
6100 | ||
6101 | else if ((commutative || ! TREE_SIDE_EFFECTS (a10)) | |
6102 | && operand_equal_p (a01, a11, 0)) | |
6103 | return fold (build (TREE_CODE (arg0), type, | |
6104 | fold (build (code, type, a00, a10)), | |
6105 | a01)); | |
6106 | } | |
6107 | ||
ebde8a27 RK |
6108 | /* See if we can build a range comparison. */ |
6109 | if (0 != (tem = fold_range_test (t))) | |
6110 | return tem; | |
6111 | ||
6d716ca8 RS |
6112 | /* Check for the possibility of merging component references. If our |
6113 | lhs is another similar operation, try to merge its rhs with our | |
6114 | rhs. Then try to merge our lhs and rhs. */ | |
e9b5e15f RK |
6115 | if (TREE_CODE (arg0) == code |
6116 | && 0 != (tem = fold_truthop (code, type, | |
6117 | TREE_OPERAND (arg0, 1), arg1))) | |
6118 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
6d716ca8 | 6119 | |
e9b5e15f RK |
6120 | if ((tem = fold_truthop (code, type, arg0, arg1)) != 0) |
6121 | return tem; | |
61f275ff | 6122 | |
6d716ca8 RS |
6123 | return t; |
6124 | ||
6125 | case TRUTH_ORIF_EXPR: | |
6126 | /* Note that the operands of this must be ints | |
6127 | and their values must be 0 or true. | |
6128 | ("true" is a fixed value perhaps depending on the language.) */ | |
6129 | /* If first arg is constant true, return it. */ | |
6130 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
13eb1f7f | 6131 | return convert (type, arg0); |
6d716ca8 RS |
6132 | case TRUTH_OR_EXPR: |
6133 | /* If either arg is constant zero, drop it. */ | |
6134 | if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0)) | |
13eb1f7f | 6135 | return non_lvalue (convert (type, arg1)); |
235cfbc4 BS |
6136 | if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1) |
6137 | /* Preserve sequence points. */ | |
6138 | && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0))) | |
13eb1f7f | 6139 | return non_lvalue (convert (type, arg0)); |
772447c5 RK |
6140 | /* If second arg is constant true, result is true, but we must |
6141 | evaluate first arg. */ | |
6142 | if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)) | |
6143 | return omit_one_operand (type, arg1, arg0); | |
80906567 RK |
6144 | /* Likewise for first arg, but note this only occurs here for |
6145 | TRUTH_OR_EXPR. */ | |
6146 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
6147 | return omit_one_operand (type, arg0, arg1); | |
6d716ca8 RS |
6148 | goto truth_andor; |
6149 | ||
772447c5 RK |
6150 | case TRUTH_XOR_EXPR: |
6151 | /* If either arg is constant zero, drop it. */ | |
6152 | if (integer_zerop (arg0)) | |
13eb1f7f | 6153 | return non_lvalue (convert (type, arg1)); |
772447c5 | 6154 | if (integer_zerop (arg1)) |
13eb1f7f | 6155 | return non_lvalue (convert (type, arg0)); |
772447c5 RK |
6156 | /* If either arg is constant true, this is a logical inversion. */ |
6157 | if (integer_onep (arg0)) | |
13eb1f7f | 6158 | return non_lvalue (convert (type, invert_truthvalue (arg1))); |
772447c5 | 6159 | if (integer_onep (arg1)) |
13eb1f7f | 6160 | return non_lvalue (convert (type, invert_truthvalue (arg0))); |
62d8b51e | 6161 | return t; |
772447c5 | 6162 | |
6d716ca8 RS |
6163 | case EQ_EXPR: |
6164 | case NE_EXPR: | |
6165 | case LT_EXPR: | |
6166 | case GT_EXPR: | |
6167 | case LE_EXPR: | |
6168 | case GE_EXPR: | |
10414089 JL |
6169 | if (FLOAT_TYPE_P (TREE_TYPE (arg0))) |
6170 | { | |
6171 | /* (-a) CMP (-b) -> b CMP a */ | |
6172 | if (TREE_CODE (arg0) == NEGATE_EXPR | |
6173 | && TREE_CODE (arg1) == NEGATE_EXPR) | |
6174 | return fold (build (code, type, TREE_OPERAND (arg1, 0), | |
6175 | TREE_OPERAND (arg0, 0))); | |
6176 | /* (-a) CMP CST -> a swap(CMP) (-CST) */ | |
6177 | if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == REAL_CST) | |
6178 | return | |
6179 | fold (build | |
b6cc0a72 KH |
6180 | (swap_tree_comparison (code), type, |
6181 | TREE_OPERAND (arg0, 0), | |
6182 | build_real (TREE_TYPE (arg1), | |
6183 | REAL_VALUE_NEGATE (TREE_REAL_CST (arg1))))); | |
10414089 JL |
6184 | /* IEEE doesn't distinguish +0 and -0 in comparisons. */ |
6185 | /* a CMP (-0) -> a CMP 0 */ | |
0d19c2a1 JL |
6186 | if (TREE_CODE (arg1) == REAL_CST |
6187 | && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (arg1))) | |
10414089 JL |
6188 | return fold (build (code, type, arg0, |
6189 | build_real (TREE_TYPE (arg1), dconst0))); | |
6190 | } | |
6191 | ||
6d716ca8 RS |
6192 | /* If one arg is a constant integer, put it last. */ |
6193 | if (TREE_CODE (arg0) == INTEGER_CST | |
6194 | && TREE_CODE (arg1) != INTEGER_CST) | |
6195 | { | |
6196 | TREE_OPERAND (t, 0) = arg1; | |
6197 | TREE_OPERAND (t, 1) = arg0; | |
6198 | arg0 = TREE_OPERAND (t, 0); | |
6199 | arg1 = TREE_OPERAND (t, 1); | |
c05a9b68 | 6200 | code = swap_tree_comparison (code); |
6d716ca8 RS |
6201 | TREE_SET_CODE (t, code); |
6202 | } | |
6203 | ||
6204 | /* Convert foo++ == CONST into ++foo == CONST + INCR. | |
6205 | First, see if one arg is constant; find the constant arg | |
6206 | and the other one. */ | |
6207 | { | |
4e86caed | 6208 | tree constop = 0, varop = NULL_TREE; |
cd7ece66 | 6209 | int constopnum = -1; |
6d716ca8 RS |
6210 | |
6211 | if (TREE_CONSTANT (arg1)) | |
cd7ece66 | 6212 | constopnum = 1, constop = arg1, varop = arg0; |
6d716ca8 | 6213 | if (TREE_CONSTANT (arg0)) |
cd7ece66 | 6214 | constopnum = 0, constop = arg0, varop = arg1; |
6d716ca8 RS |
6215 | |
6216 | if (constop && TREE_CODE (varop) == POSTINCREMENT_EXPR) | |
6217 | { | |
6d716ca8 RS |
6218 | /* This optimization is invalid for ordered comparisons |
6219 | if CONST+INCR overflows or if foo+incr might overflow. | |
c05a9b68 | 6220 | This optimization is invalid for floating point due to rounding. |
6d716ca8 | 6221 | For pointer types we assume overflow doesn't happen. */ |
e5e809f4 | 6222 | if (POINTER_TYPE_P (TREE_TYPE (varop)) |
7178e3af | 6223 | || (! FLOAT_TYPE_P (TREE_TYPE (varop)) |
c05a9b68 | 6224 | && (code == EQ_EXPR || code == NE_EXPR))) |
6d716ca8 | 6225 | { |
c05a9b68 RS |
6226 | tree newconst |
6227 | = fold (build (PLUS_EXPR, TREE_TYPE (varop), | |
6228 | constop, TREE_OPERAND (varop, 1))); | |
4d06bcc5 MM |
6229 | |
6230 | /* Do not overwrite the current varop to be a preincrement, | |
6231 | create a new node so that we won't confuse our caller who | |
6232 | might create trees and throw them away, reusing the | |
6233 | arguments that they passed to build. This shows up in | |
6234 | the THEN or ELSE parts of ?: being postincrements. */ | |
6235 | varop = build (PREINCREMENT_EXPR, TREE_TYPE (varop), | |
6236 | TREE_OPERAND (varop, 0), | |
6237 | TREE_OPERAND (varop, 1)); | |
cd7ece66 | 6238 | |
30eca391 RK |
6239 | /* If VAROP is a reference to a bitfield, we must mask |
6240 | the constant by the width of the field. */ | |
6241 | if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF | |
6242 | && DECL_BIT_FIELD(TREE_OPERAND | |
6243 | (TREE_OPERAND (varop, 0), 1))) | |
6244 | { | |
6245 | int size | |
6246 | = TREE_INT_CST_LOW (DECL_SIZE | |
6247 | (TREE_OPERAND | |
6248 | (TREE_OPERAND (varop, 0), 1))); | |
df0e526f | 6249 | tree mask, unsigned_type; |
770ae6cc | 6250 | unsigned int precision; |
df0e526f AS |
6251 | tree folded_compare; |
6252 | ||
6253 | /* First check whether the comparison would come out | |
6254 | always the same. If we don't do that we would | |
6255 | change the meaning with the masking. */ | |
6256 | if (constopnum == 0) | |
6257 | folded_compare = fold (build (code, type, constop, | |
6258 | TREE_OPERAND (varop, 0))); | |
6259 | else | |
6260 | folded_compare = fold (build (code, type, | |
6261 | TREE_OPERAND (varop, 0), | |
6262 | constop)); | |
6263 | if (integer_zerop (folded_compare) | |
6264 | || integer_onep (folded_compare)) | |
6265 | return omit_one_operand (type, folded_compare, varop); | |
6266 | ||
6267 | unsigned_type = type_for_size (size, 1); | |
6268 | precision = TYPE_PRECISION (unsigned_type); | |
6269 | mask = build_int_2 (~0, ~0); | |
6270 | TREE_TYPE (mask) = unsigned_type; | |
6271 | force_fit_type (mask, 0); | |
6272 | mask = const_binop (RSHIFT_EXPR, mask, | |
6273 | size_int (precision - size), 0); | |
30eca391 RK |
6274 | newconst = fold (build (BIT_AND_EXPR, |
6275 | TREE_TYPE (varop), newconst, | |
6276 | convert (TREE_TYPE (varop), | |
df0e526f | 6277 | mask))); |
30eca391 | 6278 | } |
30eca391 | 6279 | |
4d06bcc5 MM |
6280 | t = build (code, type, |
6281 | (constopnum == 0) ? newconst : varop, | |
6282 | (constopnum == 1) ? newconst : varop); | |
c05a9b68 | 6283 | return t; |
6d716ca8 RS |
6284 | } |
6285 | } | |
6286 | else if (constop && TREE_CODE (varop) == POSTDECREMENT_EXPR) | |
6287 | { | |
e5e809f4 | 6288 | if (POINTER_TYPE_P (TREE_TYPE (varop)) |
7178e3af | 6289 | || (! FLOAT_TYPE_P (TREE_TYPE (varop)) |
c05a9b68 | 6290 | && (code == EQ_EXPR || code == NE_EXPR))) |
6d716ca8 | 6291 | { |
c05a9b68 RS |
6292 | tree newconst |
6293 | = fold (build (MINUS_EXPR, TREE_TYPE (varop), | |
6294 | constop, TREE_OPERAND (varop, 1))); | |
4d06bcc5 MM |
6295 | |
6296 | /* Do not overwrite the current varop to be a predecrement, | |
6297 | create a new node so that we won't confuse our caller who | |
6298 | might create trees and throw them away, reusing the | |
6299 | arguments that they passed to build. This shows up in | |
6300 | the THEN or ELSE parts of ?: being postdecrements. */ | |
6301 | varop = build (PREDECREMENT_EXPR, TREE_TYPE (varop), | |
6302 | TREE_OPERAND (varop, 0), | |
6303 | TREE_OPERAND (varop, 1)); | |
30eca391 RK |
6304 | |
6305 | if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF | |
6306 | && DECL_BIT_FIELD(TREE_OPERAND | |
6307 | (TREE_OPERAND (varop, 0), 1))) | |
6308 | { | |
6309 | int size | |
6310 | = TREE_INT_CST_LOW (DECL_SIZE | |
6311 | (TREE_OPERAND | |
6312 | (TREE_OPERAND (varop, 0), 1))); | |
df0e526f | 6313 | tree mask, unsigned_type; |
770ae6cc | 6314 | unsigned int precision; |
df0e526f AS |
6315 | tree folded_compare; |
6316 | ||
6317 | if (constopnum == 0) | |
6318 | folded_compare = fold (build (code, type, constop, | |
6319 | TREE_OPERAND (varop, 0))); | |
6320 | else | |
6321 | folded_compare = fold (build (code, type, | |
6322 | TREE_OPERAND (varop, 0), | |
6323 | constop)); | |
6324 | if (integer_zerop (folded_compare) | |
6325 | || integer_onep (folded_compare)) | |
6326 | return omit_one_operand (type, folded_compare, varop); | |
6327 | ||
6328 | unsigned_type = type_for_size (size, 1); | |
6329 | precision = TYPE_PRECISION (unsigned_type); | |
6330 | mask = build_int_2 (~0, ~0); | |
6331 | TREE_TYPE (mask) = TREE_TYPE (varop); | |
6332 | force_fit_type (mask, 0); | |
6333 | mask = const_binop (RSHIFT_EXPR, mask, | |
6334 | size_int (precision - size), 0); | |
30eca391 RK |
6335 | newconst = fold (build (BIT_AND_EXPR, |
6336 | TREE_TYPE (varop), newconst, | |
6337 | convert (TREE_TYPE (varop), | |
df0e526f | 6338 | mask))); |
30eca391 | 6339 | } |
30eca391 | 6340 | |
4d06bcc5 MM |
6341 | t = build (code, type, |
6342 | (constopnum == 0) ? newconst : varop, | |
6343 | (constopnum == 1) ? newconst : varop); | |
c05a9b68 | 6344 | return t; |
6d716ca8 RS |
6345 | } |
6346 | } | |
6347 | } | |
6348 | ||
6349 | /* Change X >= CST to X > (CST - 1) if CST is positive. */ | |
6350 | if (TREE_CODE (arg1) == INTEGER_CST | |
6351 | && TREE_CODE (arg0) != INTEGER_CST | |
d0cb4c65 | 6352 | && tree_int_cst_sgn (arg1) > 0) |
6d716ca8 RS |
6353 | { |
6354 | switch (TREE_CODE (t)) | |
6355 | { | |
6356 | case GE_EXPR: | |
6357 | code = GT_EXPR; | |
91d33e36 | 6358 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
cd7ece66 | 6359 | t = build (code, type, TREE_OPERAND (t, 0), arg1); |
6d716ca8 RS |
6360 | break; |
6361 | ||
6362 | case LT_EXPR: | |
6363 | code = LE_EXPR; | |
91d33e36 | 6364 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
cd7ece66 RK |
6365 | t = build (code, type, TREE_OPERAND (t, 0), arg1); |
6366 | break; | |
e9a25f70 JL |
6367 | |
6368 | default: | |
6369 | break; | |
6d716ca8 RS |
6370 | } |
6371 | } | |
6372 | ||
14a774a9 RK |
6373 | /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or |
6374 | a MINUS_EXPR of a constant, we can convert it into a comparison with | |
6375 | a revised constant as long as no overflow occurs. */ | |
6376 | if ((code == EQ_EXPR || code == NE_EXPR) | |
6377 | && TREE_CODE (arg1) == INTEGER_CST | |
6378 | && (TREE_CODE (arg0) == PLUS_EXPR | |
6379 | || TREE_CODE (arg0) == MINUS_EXPR) | |
6380 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
6381 | && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR | |
6382 | ? MINUS_EXPR : PLUS_EXPR, | |
6383 | arg1, TREE_OPERAND (arg0, 1), 0)) | |
6384 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
6385 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
6386 | ||
6387 | /* Similarly for a NEGATE_EXPR. */ | |
6388 | else if ((code == EQ_EXPR || code == NE_EXPR) | |
6389 | && TREE_CODE (arg0) == NEGATE_EXPR | |
6390 | && TREE_CODE (arg1) == INTEGER_CST | |
1baa375f | 6391 | && 0 != (tem = negate_expr (arg1)) |
14a774a9 RK |
6392 | && TREE_CODE (tem) == INTEGER_CST |
6393 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
6394 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
6395 | ||
6396 | /* If we have X - Y == 0, we can convert that to X == Y and similarly | |
6397 | for !=. Don't do this for ordered comparisons due to overflow. */ | |
6398 | else if ((code == NE_EXPR || code == EQ_EXPR) | |
6399 | && integer_zerop (arg1) && TREE_CODE (arg0) == MINUS_EXPR) | |
6400 | return fold (build (code, type, | |
6401 | TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1))); | |
6402 | ||
6403 | /* If we are widening one operand of an integer comparison, | |
6404 | see if the other operand is similarly being widened. Perhaps we | |
6405 | can do the comparison in the narrower type. */ | |
6406 | else if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE | |
6407 | && TREE_CODE (arg0) == NOP_EXPR | |
6408 | && (tem = get_unwidened (arg0, NULL_TREE)) != arg0 | |
6409 | && (t1 = get_unwidened (arg1, TREE_TYPE (tem))) != 0 | |
6410 | && (TREE_TYPE (t1) == TREE_TYPE (tem) | |
6411 | || (TREE_CODE (t1) == INTEGER_CST | |
6412 | && int_fits_type_p (t1, TREE_TYPE (tem))))) | |
6413 | return fold (build (code, type, tem, convert (TREE_TYPE (tem), t1))); | |
b6cc0a72 | 6414 | |
14a774a9 RK |
6415 | /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a |
6416 | constant, we can simplify it. */ | |
6417 | else if (TREE_CODE (arg1) == INTEGER_CST | |
6418 | && (TREE_CODE (arg0) == MIN_EXPR | |
6419 | || TREE_CODE (arg0) == MAX_EXPR) | |
6420 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
6421 | return optimize_minmax_comparison (t); | |
6422 | ||
6423 | /* If we are comparing an ABS_EXPR with a constant, we can | |
6424 | convert all the cases into explicit comparisons, but they may | |
6425 | well not be faster than doing the ABS and one comparison. | |
6426 | But ABS (X) <= C is a range comparison, which becomes a subtraction | |
6427 | and a comparison, and is probably faster. */ | |
6428 | else if (code == LE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
6429 | && TREE_CODE (arg0) == ABS_EXPR | |
1baa375f RK |
6430 | && ! TREE_SIDE_EFFECTS (arg0) |
6431 | && (0 != (tem = negate_expr (arg1))) | |
6432 | && TREE_CODE (tem) == INTEGER_CST | |
6433 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
6434 | return fold (build (TRUTH_ANDIF_EXPR, type, | |
6435 | build (GE_EXPR, type, TREE_OPERAND (arg0, 0), tem), | |
6436 | build (LE_EXPR, type, | |
6437 | TREE_OPERAND (arg0, 0), arg1))); | |
b6cc0a72 | 6438 | |
6d716ca8 RS |
6439 | /* If this is an EQ or NE comparison with zero and ARG0 is |
6440 | (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require | |
6441 | two operations, but the latter can be done in one less insn | |
e9a25f70 | 6442 | on machines that have only two-operand insns or on which a |
6d716ca8 RS |
6443 | constant cannot be the first operand. */ |
6444 | if (integer_zerop (arg1) && (code == EQ_EXPR || code == NE_EXPR) | |
6445 | && TREE_CODE (arg0) == BIT_AND_EXPR) | |
6446 | { | |
6447 | if (TREE_CODE (TREE_OPERAND (arg0, 0)) == LSHIFT_EXPR | |
6448 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 0), 0))) | |
6449 | return | |
6450 | fold (build (code, type, | |
6451 | build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
6452 | build (RSHIFT_EXPR, | |
6453 | TREE_TYPE (TREE_OPERAND (arg0, 0)), | |
6454 | TREE_OPERAND (arg0, 1), | |
6455 | TREE_OPERAND (TREE_OPERAND (arg0, 0), 1)), | |
6456 | convert (TREE_TYPE (arg0), | |
6457 | integer_one_node)), | |
6458 | arg1)); | |
6459 | else if (TREE_CODE (TREE_OPERAND (arg0, 1)) == LSHIFT_EXPR | |
6460 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 1), 0))) | |
6461 | return | |
6462 | fold (build (code, type, | |
6463 | build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
6464 | build (RSHIFT_EXPR, | |
6465 | TREE_TYPE (TREE_OPERAND (arg0, 1)), | |
6466 | TREE_OPERAND (arg0, 0), | |
6467 | TREE_OPERAND (TREE_OPERAND (arg0, 1), 1)), | |
6468 | convert (TREE_TYPE (arg0), | |
6469 | integer_one_node)), | |
6470 | arg1)); | |
6471 | } | |
6472 | ||
05a0d5ea | 6473 | /* If this is an NE or EQ comparison of zero against the result of a |
79bf94d3 RK |
6474 | signed MOD operation whose second operand is a power of 2, make |
6475 | the MOD operation unsigned since it is simpler and equivalent. */ | |
05a0d5ea RK |
6476 | if ((code == NE_EXPR || code == EQ_EXPR) |
6477 | && integer_zerop (arg1) | |
6478 | && ! TREE_UNSIGNED (TREE_TYPE (arg0)) | |
6479 | && (TREE_CODE (arg0) == TRUNC_MOD_EXPR | |
6480 | || TREE_CODE (arg0) == CEIL_MOD_EXPR | |
6481 | || TREE_CODE (arg0) == FLOOR_MOD_EXPR | |
79bf94d3 RK |
6482 | || TREE_CODE (arg0) == ROUND_MOD_EXPR) |
6483 | && integer_pow2p (TREE_OPERAND (arg0, 1))) | |
05a0d5ea RK |
6484 | { |
6485 | tree newtype = unsigned_type (TREE_TYPE (arg0)); | |
6486 | tree newmod = build (TREE_CODE (arg0), newtype, | |
6487 | convert (newtype, TREE_OPERAND (arg0, 0)), | |
6488 | convert (newtype, TREE_OPERAND (arg0, 1))); | |
6489 | ||
6490 | return build (code, type, newmod, convert (newtype, arg1)); | |
6491 | } | |
6492 | ||
6d716ca8 RS |
6493 | /* If this is an NE comparison of zero with an AND of one, remove the |
6494 | comparison since the AND will give the correct value. */ | |
6495 | if (code == NE_EXPR && integer_zerop (arg1) | |
6496 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
6497 | && integer_onep (TREE_OPERAND (arg0, 1))) | |
6498 | return convert (type, arg0); | |
6499 | ||
6500 | /* If we have (A & C) == C where C is a power of 2, convert this into | |
6501 | (A & C) != 0. Similarly for NE_EXPR. */ | |
6502 | if ((code == EQ_EXPR || code == NE_EXPR) | |
6503 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
6504 | && integer_pow2p (TREE_OPERAND (arg0, 1)) | |
6505 | && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)) | |
6506 | return build (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type, | |
6507 | arg0, integer_zero_node); | |
6508 | ||
e92d3048 | 6509 | /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0 |
34b1b41f | 6510 | and similarly for >= into !=. */ |
e92d3048 RK |
6511 | if ((code == LT_EXPR || code == GE_EXPR) |
6512 | && TREE_UNSIGNED (TREE_TYPE (arg0)) | |
6513 | && TREE_CODE (arg1) == LSHIFT_EXPR | |
6514 | && integer_onep (TREE_OPERAND (arg1, 0))) | |
b6cc0a72 | 6515 | return build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type, |
e92d3048 RK |
6516 | build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0, |
6517 | TREE_OPERAND (arg1, 1)), | |
6518 | convert (TREE_TYPE (arg0), integer_zero_node)); | |
6519 | ||
6520 | else if ((code == LT_EXPR || code == GE_EXPR) | |
6521 | && TREE_UNSIGNED (TREE_TYPE (arg0)) | |
6522 | && (TREE_CODE (arg1) == NOP_EXPR | |
6523 | || TREE_CODE (arg1) == CONVERT_EXPR) | |
6524 | && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR | |
6525 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0))) | |
6526 | return | |
6527 | build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type, | |
6528 | convert (TREE_TYPE (arg0), | |
6529 | build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0, | |
6530 | TREE_OPERAND (TREE_OPERAND (arg1, 0), 1))), | |
6531 | convert (TREE_TYPE (arg0), integer_zero_node)); | |
6532 | ||
c05a9b68 RS |
6533 | /* Simplify comparison of something with itself. (For IEEE |
6534 | floating-point, we can only do some of these simplifications.) */ | |
6535 | if (operand_equal_p (arg0, arg1, 0)) | |
6d716ca8 RS |
6536 | { |
6537 | switch (code) | |
6538 | { | |
6539 | case EQ_EXPR: | |
6540 | case GE_EXPR: | |
6541 | case LE_EXPR: | |
1f2f8b29 | 6542 | if (! FLOAT_TYPE_P (TREE_TYPE (arg0))) |
f628873f | 6543 | return constant_boolean_node (1, type); |
c05a9b68 RS |
6544 | code = EQ_EXPR; |
6545 | TREE_SET_CODE (t, code); | |
6546 | break; | |
6547 | ||
6d716ca8 | 6548 | case NE_EXPR: |
c05a9b68 | 6549 | /* For NE, we can only do this simplification if integer. */ |
1f2f8b29 | 6550 | if (FLOAT_TYPE_P (TREE_TYPE (arg0))) |
c05a9b68 | 6551 | break; |
0f41302f | 6552 | /* ... fall through ... */ |
6d716ca8 RS |
6553 | case GT_EXPR: |
6554 | case LT_EXPR: | |
f628873f | 6555 | return constant_boolean_node (0, type); |
e9a25f70 JL |
6556 | default: |
6557 | abort (); | |
6d716ca8 RS |
6558 | } |
6559 | } | |
6560 | ||
6561 | /* An unsigned comparison against 0 can be simplified. */ | |
6562 | if (integer_zerop (arg1) | |
7178e3af | 6563 | && (INTEGRAL_TYPE_P (TREE_TYPE (arg1)) |
e5e809f4 | 6564 | || POINTER_TYPE_P (TREE_TYPE (arg1))) |
6d716ca8 RS |
6565 | && TREE_UNSIGNED (TREE_TYPE (arg1))) |
6566 | { | |
6567 | switch (TREE_CODE (t)) | |
6568 | { | |
6569 | case GT_EXPR: | |
c05a9b68 | 6570 | code = NE_EXPR; |
6d716ca8 RS |
6571 | TREE_SET_CODE (t, NE_EXPR); |
6572 | break; | |
6573 | case LE_EXPR: | |
c05a9b68 | 6574 | code = EQ_EXPR; |
6d716ca8 RS |
6575 | TREE_SET_CODE (t, EQ_EXPR); |
6576 | break; | |
6577 | case GE_EXPR: | |
56f8e5e6 RK |
6578 | return omit_one_operand (type, |
6579 | convert (type, integer_one_node), | |
6580 | arg0); | |
6d716ca8 | 6581 | case LT_EXPR: |
56f8e5e6 RK |
6582 | return omit_one_operand (type, |
6583 | convert (type, integer_zero_node), | |
6584 | arg0); | |
e9a25f70 JL |
6585 | default: |
6586 | break; | |
6d716ca8 RS |
6587 | } |
6588 | } | |
6589 | ||
14a774a9 RK |
6590 | /* Comparisons with the highest or lowest possible integer of |
6591 | the specified size will have known values and an unsigned | |
6592 | <= 0x7fffffff can be simplified. */ | |
e9a25f70 | 6593 | { |
14a774a9 RK |
6594 | int width = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg1))); |
6595 | ||
e9a25f70 JL |
6596 | if (TREE_CODE (arg1) == INTEGER_CST |
6597 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
6598 | && width <= HOST_BITS_PER_WIDE_INT | |
e9a25f70 | 6599 | && (INTEGRAL_TYPE_P (TREE_TYPE (arg1)) |
14a774a9 | 6600 | || POINTER_TYPE_P (TREE_TYPE (arg1)))) |
e9a25f70 | 6601 | { |
14a774a9 RK |
6602 | if (TREE_INT_CST_HIGH (arg1) == 0 |
6603 | && (TREE_INT_CST_LOW (arg1) | |
05bccae2 | 6604 | == ((unsigned HOST_WIDE_INT) 1 << (width - 1)) - 1) |
14a774a9 RK |
6605 | && ! TREE_UNSIGNED (TREE_TYPE (arg1))) |
6606 | switch (TREE_CODE (t)) | |
6607 | { | |
6608 | case GT_EXPR: | |
6609 | return omit_one_operand (type, | |
6610 | convert (type, integer_zero_node), | |
6611 | arg0); | |
6612 | case GE_EXPR: | |
6613 | TREE_SET_CODE (t, EQ_EXPR); | |
6614 | break; | |
6615 | ||
6616 | case LE_EXPR: | |
6617 | return omit_one_operand (type, | |
6618 | convert (type, integer_one_node), | |
6619 | arg0); | |
6620 | case LT_EXPR: | |
6621 | TREE_SET_CODE (t, NE_EXPR); | |
6622 | break; | |
6623 | ||
6624 | default: | |
6625 | break; | |
6626 | } | |
6627 | ||
6628 | else if (TREE_INT_CST_HIGH (arg1) == -1 | |
6629 | && (- TREE_INT_CST_LOW (arg1) | |
05bccae2 | 6630 | == ((unsigned HOST_WIDE_INT) 1 << (width - 1))) |
14a774a9 RK |
6631 | && ! TREE_UNSIGNED (TREE_TYPE (arg1))) |
6632 | switch (TREE_CODE (t)) | |
6633 | { | |
6634 | case LT_EXPR: | |
6635 | return omit_one_operand (type, | |
6636 | convert (type, integer_zero_node), | |
6637 | arg0); | |
6638 | case LE_EXPR: | |
6639 | TREE_SET_CODE (t, EQ_EXPR); | |
6640 | break; | |
6641 | ||
6642 | case GE_EXPR: | |
6643 | return omit_one_operand (type, | |
6644 | convert (type, integer_one_node), | |
6645 | arg0); | |
6646 | case GT_EXPR: | |
6647 | TREE_SET_CODE (t, NE_EXPR); | |
6648 | break; | |
6649 | ||
6650 | default: | |
6651 | break; | |
6652 | } | |
6653 | ||
6654 | else if (TREE_INT_CST_HIGH (arg1) == 0 | |
6655 | && (TREE_INT_CST_LOW (arg1) | |
05bccae2 | 6656 | == ((unsigned HOST_WIDE_INT) 1 << (width - 1)) - 1) |
d791ea1e JJ |
6657 | && TREE_UNSIGNED (TREE_TYPE (arg1)) |
6658 | /* signed_type does not work on pointer types. */ | |
6659 | && INTEGRAL_TYPE_P (TREE_TYPE (arg1))) | |
b6cc0a72 | 6660 | |
14a774a9 RK |
6661 | switch (TREE_CODE (t)) |
6662 | { | |
6663 | case LE_EXPR: | |
6664 | return fold (build (GE_EXPR, type, | |
6665 | convert (signed_type (TREE_TYPE (arg0)), | |
6666 | arg0), | |
6667 | convert (signed_type (TREE_TYPE (arg1)), | |
6668 | integer_zero_node))); | |
6669 | case GT_EXPR: | |
6670 | return fold (build (LT_EXPR, type, | |
6671 | convert (signed_type (TREE_TYPE (arg0)), | |
6672 | arg0), | |
6673 | convert (signed_type (TREE_TYPE (arg1)), | |
6674 | integer_zero_node))); | |
6675 | ||
6676 | default: | |
6677 | break; | |
6678 | } | |
e9a25f70 JL |
6679 | } |
6680 | } | |
6681 | ||
c05a9b68 RS |
6682 | /* If we are comparing an expression that just has comparisons |
6683 | of two integer values, arithmetic expressions of those comparisons, | |
6684 | and constants, we can simplify it. There are only three cases | |
6685 | to check: the two values can either be equal, the first can be | |
6686 | greater, or the second can be greater. Fold the expression for | |
6687 | those three values. Since each value must be 0 or 1, we have | |
6688 | eight possibilities, each of which corresponds to the constant 0 | |
6689 | or 1 or one of the six possible comparisons. | |
6690 | ||
6691 | This handles common cases like (a > b) == 0 but also handles | |
6692 | expressions like ((x > y) - (y > x)) > 0, which supposedly | |
6693 | occur in macroized code. */ | |
6694 | ||
6695 | if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST) | |
6696 | { | |
6697 | tree cval1 = 0, cval2 = 0; | |
35e66bd1 | 6698 | int save_p = 0; |
c05a9b68 | 6699 | |
35e66bd1 | 6700 | if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p) |
c05a9b68 RS |
6701 | /* Don't handle degenerate cases here; they should already |
6702 | have been handled anyway. */ | |
6703 | && cval1 != 0 && cval2 != 0 | |
6704 | && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2)) | |
6705 | && TREE_TYPE (cval1) == TREE_TYPE (cval2) | |
7178e3af | 6706 | && INTEGRAL_TYPE_P (TREE_TYPE (cval1)) |
e1ee5cdc RH |
6707 | && TYPE_MAX_VALUE (TREE_TYPE (cval1)) |
6708 | && TYPE_MAX_VALUE (TREE_TYPE (cval2)) | |
c05a9b68 RS |
6709 | && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)), |
6710 | TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0)) | |
6711 | { | |
6712 | tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1)); | |
6713 | tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1)); | |
6714 | ||
6715 | /* We can't just pass T to eval_subst in case cval1 or cval2 | |
6716 | was the same as ARG1. */ | |
6717 | ||
6718 | tree high_result | |
6719 | = fold (build (code, type, | |
6720 | eval_subst (arg0, cval1, maxval, cval2, minval), | |
6721 | arg1)); | |
6722 | tree equal_result | |
6723 | = fold (build (code, type, | |
6724 | eval_subst (arg0, cval1, maxval, cval2, maxval), | |
6725 | arg1)); | |
6726 | tree low_result | |
6727 | = fold (build (code, type, | |
6728 | eval_subst (arg0, cval1, minval, cval2, maxval), | |
6729 | arg1)); | |
6730 | ||
6731 | /* All three of these results should be 0 or 1. Confirm they | |
6732 | are. Then use those values to select the proper code | |
6733 | to use. */ | |
6734 | ||
6735 | if ((integer_zerop (high_result) | |
6736 | || integer_onep (high_result)) | |
6737 | && (integer_zerop (equal_result) | |
6738 | || integer_onep (equal_result)) | |
6739 | && (integer_zerop (low_result) | |
6740 | || integer_onep (low_result))) | |
6741 | { | |
6742 | /* Make a 3-bit mask with the high-order bit being the | |
6743 | value for `>', the next for '=', and the low for '<'. */ | |
6744 | switch ((integer_onep (high_result) * 4) | |
6745 | + (integer_onep (equal_result) * 2) | |
6746 | + integer_onep (low_result)) | |
6747 | { | |
6748 | case 0: | |
6749 | /* Always false. */ | |
13837058 | 6750 | return omit_one_operand (type, integer_zero_node, arg0); |
c05a9b68 RS |
6751 | case 1: |
6752 | code = LT_EXPR; | |
6753 | break; | |
6754 | case 2: | |
6755 | code = EQ_EXPR; | |
6756 | break; | |
6757 | case 3: | |
6758 | code = LE_EXPR; | |
6759 | break; | |
6760 | case 4: | |
6761 | code = GT_EXPR; | |
6762 | break; | |
6763 | case 5: | |
6764 | code = NE_EXPR; | |
6765 | break; | |
6766 | case 6: | |
6767 | code = GE_EXPR; | |
6768 | break; | |
6769 | case 7: | |
6770 | /* Always true. */ | |
13837058 | 6771 | return omit_one_operand (type, integer_one_node, arg0); |
c05a9b68 RS |
6772 | } |
6773 | ||
35e66bd1 RK |
6774 | t = build (code, type, cval1, cval2); |
6775 | if (save_p) | |
6776 | return save_expr (t); | |
6777 | else | |
6778 | return fold (t); | |
c05a9b68 RS |
6779 | } |
6780 | } | |
6781 | } | |
6782 | ||
6783 | /* If this is a comparison of a field, we may be able to simplify it. */ | |
9c922ec7 MM |
6784 | if ((TREE_CODE (arg0) == COMPONENT_REF |
6785 | || TREE_CODE (arg0) == BIT_FIELD_REF) | |
6786 | && (code == EQ_EXPR || code == NE_EXPR) | |
6787 | /* Handle the constant case even without -O | |
6788 | to make sure the warnings are given. */ | |
6789 | && (optimize || TREE_CODE (arg1) == INTEGER_CST)) | |
6790 | { | |
6791 | t1 = optimize_bit_field_compare (code, type, arg0, arg1); | |
6792 | return t1 ? t1 : t; | |
6793 | } | |
c05a9b68 | 6794 | |
9ec36da5 JL |
6795 | /* If this is a comparison of complex values and either or both sides |
6796 | are a COMPLEX_EXPR or COMPLEX_CST, it is best to split up the | |
6797 | comparisons and join them with a TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR. | |
6798 | This may prevent needless evaluations. */ | |
95aa28ae RK |
6799 | if ((code == EQ_EXPR || code == NE_EXPR) |
6800 | && TREE_CODE (TREE_TYPE (arg0)) == COMPLEX_TYPE | |
6801 | && (TREE_CODE (arg0) == COMPLEX_EXPR | |
9ec36da5 JL |
6802 | || TREE_CODE (arg1) == COMPLEX_EXPR |
6803 | || TREE_CODE (arg0) == COMPLEX_CST | |
6804 | || TREE_CODE (arg1) == COMPLEX_CST)) | |
95aa28ae RK |
6805 | { |
6806 | tree subtype = TREE_TYPE (TREE_TYPE (arg0)); | |
f0b8d9aa AS |
6807 | tree real0, imag0, real1, imag1; |
6808 | ||
6809 | arg0 = save_expr (arg0); | |
6810 | arg1 = save_expr (arg1); | |
6811 | real0 = fold (build1 (REALPART_EXPR, subtype, arg0)); | |
6812 | imag0 = fold (build1 (IMAGPART_EXPR, subtype, arg0)); | |
6813 | real1 = fold (build1 (REALPART_EXPR, subtype, arg1)); | |
6814 | imag1 = fold (build1 (IMAGPART_EXPR, subtype, arg1)); | |
95aa28ae RK |
6815 | |
6816 | return fold (build ((code == EQ_EXPR ? TRUTH_ANDIF_EXPR | |
6817 | : TRUTH_ORIF_EXPR), | |
6818 | type, | |
6819 | fold (build (code, type, real0, real1)), | |
6820 | fold (build (code, type, imag0, imag1)))); | |
6821 | } | |
6822 | ||
c05a9b68 RS |
6823 | /* From here on, the only cases we handle are when the result is |
6824 | known to be a constant. | |
6825 | ||
6826 | To compute GT, swap the arguments and do LT. | |
6d716ca8 RS |
6827 | To compute GE, do LT and invert the result. |
6828 | To compute LE, swap the arguments, do LT and invert the result. | |
c05a9b68 RS |
6829 | To compute NE, do EQ and invert the result. |
6830 | ||
6831 | Therefore, the code below must handle only EQ and LT. */ | |
6832 | ||
6d716ca8 RS |
6833 | if (code == LE_EXPR || code == GT_EXPR) |
6834 | { | |
c05a9b68 RS |
6835 | tem = arg0, arg0 = arg1, arg1 = tem; |
6836 | code = swap_tree_comparison (code); | |
6837 | } | |
6838 | ||
6839 | /* Note that it is safe to invert for real values here because we | |
6840 | will check below in the one case that it matters. */ | |
6841 | ||
14a774a9 | 6842 | t1 = NULL_TREE; |
c05a9b68 RS |
6843 | invert = 0; |
6844 | if (code == NE_EXPR || code == GE_EXPR) | |
6845 | { | |
6846 | invert = 1; | |
6847 | code = invert_tree_comparison (code); | |
6d716ca8 RS |
6848 | } |
6849 | ||
6850 | /* Compute a result for LT or EQ if args permit; | |
6851 | otherwise return T. */ | |
c05a9b68 | 6852 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) |
6d716ca8 | 6853 | { |
c05a9b68 | 6854 | if (code == EQ_EXPR) |
05bccae2 | 6855 | t1 = build_int_2 (tree_int_cst_equal (arg0, arg1), 0); |
6d716ca8 | 6856 | else |
c05a9b68 RS |
6857 | t1 = build_int_2 ((TREE_UNSIGNED (TREE_TYPE (arg0)) |
6858 | ? INT_CST_LT_UNSIGNED (arg0, arg1) | |
6859 | : INT_CST_LT (arg0, arg1)), | |
6860 | 0); | |
6d716ca8 | 6861 | } |
c05a9b68 | 6862 | |
e80c9ccb | 6863 | #if 0 /* This is no longer useful, but breaks some real code. */ |
6d716ca8 RS |
6864 | /* Assume a nonexplicit constant cannot equal an explicit one, |
6865 | since such code would be undefined anyway. | |
6866 | Exception: on sysvr4, using #pragma weak, | |
6867 | a label can come out as 0. */ | |
6868 | else if (TREE_CODE (arg1) == INTEGER_CST | |
6869 | && !integer_zerop (arg1) | |
6870 | && TREE_CONSTANT (arg0) | |
6871 | && TREE_CODE (arg0) == ADDR_EXPR | |
c05a9b68 RS |
6872 | && code == EQ_EXPR) |
6873 | t1 = build_int_2 (0, 0); | |
e80c9ccb | 6874 | #endif |
6d716ca8 | 6875 | /* Two real constants can be compared explicitly. */ |
c05a9b68 | 6876 | else if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST) |
6d716ca8 | 6877 | { |
c05a9b68 RS |
6878 | /* If either operand is a NaN, the result is false with two |
6879 | exceptions: First, an NE_EXPR is true on NaNs, but that case | |
6880 | is already handled correctly since we will be inverting the | |
6881 | result for NE_EXPR. Second, if we had inverted a LE_EXPR | |
6882 | or a GE_EXPR into a LT_EXPR, we must return true so that it | |
6883 | will be inverted into false. */ | |
6884 | ||
6885 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg0)) | |
6886 | || REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))) | |
6887 | t1 = build_int_2 (invert && code == LT_EXPR, 0); | |
6888 | ||
6889 | else if (code == EQ_EXPR) | |
6890 | t1 = build_int_2 (REAL_VALUES_EQUAL (TREE_REAL_CST (arg0), | |
6891 | TREE_REAL_CST (arg1)), | |
6892 | 0); | |
6d716ca8 | 6893 | else |
c05a9b68 RS |
6894 | t1 = build_int_2 (REAL_VALUES_LESS (TREE_REAL_CST (arg0), |
6895 | TREE_REAL_CST (arg1)), | |
6896 | 0); | |
6d716ca8 RS |
6897 | } |
6898 | ||
c05a9b68 RS |
6899 | if (t1 == NULL_TREE) |
6900 | return t; | |
6901 | ||
6902 | if (invert) | |
6903 | TREE_INT_CST_LOW (t1) ^= 1; | |
6904 | ||
6905 | TREE_TYPE (t1) = type; | |
c651e1e0 MM |
6906 | if (TREE_CODE (type) == BOOLEAN_TYPE) |
6907 | return truthvalue_conversion (t1); | |
c05a9b68 | 6908 | return t1; |
6d716ca8 RS |
6909 | |
6910 | case COND_EXPR: | |
a5e9b124 JW |
6911 | /* Pedantic ANSI C says that a conditional expression is never an lvalue, |
6912 | so all simple results must be passed through pedantic_non_lvalue. */ | |
6d716ca8 | 6913 | if (TREE_CODE (arg0) == INTEGER_CST) |
a5e9b124 JW |
6914 | return pedantic_non_lvalue |
6915 | (TREE_OPERAND (t, (integer_zerop (arg0) ? 2 : 1))); | |
6d716ca8 | 6916 | else if (operand_equal_p (arg1, TREE_OPERAND (expr, 2), 0)) |
4ab3cb65 | 6917 | return pedantic_omit_one_operand (type, arg1, arg0); |
6d716ca8 | 6918 | |
c05a9b68 RS |
6919 | /* If the second operand is zero, invert the comparison and swap |
6920 | the second and third operands. Likewise if the second operand | |
6921 | is constant and the third is not or if the third operand is | |
6922 | equivalent to the first operand of the comparison. */ | |
6d716ca8 | 6923 | |
c05a9b68 RS |
6924 | if (integer_zerop (arg1) |
6925 | || (TREE_CONSTANT (arg1) && ! TREE_CONSTANT (TREE_OPERAND (t, 2))) | |
6926 | || (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' | |
6927 | && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0), | |
6928 | TREE_OPERAND (t, 2), | |
6929 | TREE_OPERAND (arg0, 1)))) | |
6930 | { | |
6931 | /* See if this can be inverted. If it can't, possibly because | |
6932 | it was a floating-point inequality comparison, don't do | |
6933 | anything. */ | |
6934 | tem = invert_truthvalue (arg0); | |
6d716ca8 | 6935 | |
c05a9b68 RS |
6936 | if (TREE_CODE (tem) != TRUTH_NOT_EXPR) |
6937 | { | |
cd7ece66 RK |
6938 | t = build (code, type, tem, |
6939 | TREE_OPERAND (t, 2), TREE_OPERAND (t, 1)); | |
6940 | arg0 = tem; | |
a58bd508 MT |
6941 | /* arg1 should be the first argument of the new T. */ |
6942 | arg1 = TREE_OPERAND (t, 1); | |
3a96b5eb | 6943 | STRIP_NOPS (arg1); |
c05a9b68 RS |
6944 | } |
6945 | } | |
6d716ca8 | 6946 | |
c05a9b68 RS |
6947 | /* If we have A op B ? A : C, we may be able to convert this to a |
6948 | simpler expression, depending on the operation and the values | |
b5c52586 RS |
6949 | of B and C. IEEE floating point prevents this though, |
6950 | because A or B might be -0.0 or a NaN. */ | |
6d716ca8 | 6951 | |
c05a9b68 | 6952 | if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' |
b5c52586 | 6953 | && (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
fab446b8 | 6954 | || ! FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 0))) |
de6c5979 | 6955 | || flag_unsafe_math_optimizations) |
c05a9b68 RS |
6956 | && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0), |
6957 | arg1, TREE_OPERAND (arg0, 1))) | |
6d716ca8 | 6958 | { |
c05a9b68 RS |
6959 | tree arg2 = TREE_OPERAND (t, 2); |
6960 | enum tree_code comp_code = TREE_CODE (arg0); | |
6961 | ||
3a96b5eb RK |
6962 | STRIP_NOPS (arg2); |
6963 | ||
c05a9b68 RS |
6964 | /* If we have A op 0 ? A : -A, this is A, -A, abs (A), or abs (-A), |
6965 | depending on the comparison operation. */ | |
68c6b3a9 DE |
6966 | if ((FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 1))) |
6967 | ? real_zerop (TREE_OPERAND (arg0, 1)) | |
6968 | : integer_zerop (TREE_OPERAND (arg0, 1))) | |
c05a9b68 RS |
6969 | && TREE_CODE (arg2) == NEGATE_EXPR |
6970 | && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0)) | |
6971 | switch (comp_code) | |
6972 | { | |
6973 | case EQ_EXPR: | |
c9869b75 | 6974 | return |
b8fbe62c RK |
6975 | pedantic_non_lvalue |
6976 | (convert (type, | |
6977 | negate_expr | |
6978 | (convert (TREE_TYPE (TREE_OPERAND (t, 1)), | |
6979 | arg1)))); | |
6980 | ||
c05a9b68 | 6981 | case NE_EXPR: |
a5e9b124 | 6982 | return pedantic_non_lvalue (convert (type, arg1)); |
c05a9b68 RS |
6983 | case GE_EXPR: |
6984 | case GT_EXPR: | |
899f1ed6 RH |
6985 | if (TREE_UNSIGNED (TREE_TYPE (arg1))) |
6986 | arg1 = convert (signed_type (TREE_TYPE (arg1)), arg1); | |
a5e9b124 | 6987 | return pedantic_non_lvalue |
21403f14 RK |
6988 | (convert (type, fold (build1 (ABS_EXPR, |
6989 | TREE_TYPE (arg1), arg1)))); | |
c05a9b68 RS |
6990 | case LE_EXPR: |
6991 | case LT_EXPR: | |
899f1ed6 RH |
6992 | if (TREE_UNSIGNED (TREE_TYPE (arg1))) |
6993 | arg1 = convert (signed_type (TREE_TYPE (arg1)), arg1); | |
a5e9b124 | 6994 | return pedantic_non_lvalue |
1baa375f RK |
6995 | (negate_expr (convert (type, |
6996 | fold (build1 (ABS_EXPR, | |
6997 | TREE_TYPE (arg1), | |
6998 | arg1))))); | |
e9a25f70 JL |
6999 | default: |
7000 | abort (); | |
c05a9b68 | 7001 | } |
6d716ca8 | 7002 | |
c05a9b68 RS |
7003 | /* If this is A != 0 ? A : 0, this is simply A. For ==, it is |
7004 | always zero. */ | |
6d716ca8 | 7005 | |
29ebe69a | 7006 | if (integer_zerop (TREE_OPERAND (arg0, 1)) && integer_zerop (arg2)) |
c05a9b68 RS |
7007 | { |
7008 | if (comp_code == NE_EXPR) | |
a5e9b124 | 7009 | return pedantic_non_lvalue (convert (type, arg1)); |
c05a9b68 | 7010 | else if (comp_code == EQ_EXPR) |
a5e9b124 | 7011 | return pedantic_non_lvalue (convert (type, integer_zero_node)); |
c05a9b68 RS |
7012 | } |
7013 | ||
7014 | /* If this is A op B ? A : B, this is either A, B, min (A, B), | |
7015 | or max (A, B), depending on the operation. */ | |
7016 | ||
7017 | if (operand_equal_for_comparison_p (TREE_OPERAND (arg0, 1), | |
7018 | arg2, TREE_OPERAND (arg0, 0))) | |
3a96b5eb RK |
7019 | { |
7020 | tree comp_op0 = TREE_OPERAND (arg0, 0); | |
7021 | tree comp_op1 = TREE_OPERAND (arg0, 1); | |
7022 | tree comp_type = TREE_TYPE (comp_op0); | |
7023 | ||
a7833bec JM |
7024 | /* Avoid adding NOP_EXPRs in case this is an lvalue. */ |
7025 | if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type)) | |
7026 | comp_type = type; | |
7027 | ||
3a96b5eb RK |
7028 | switch (comp_code) |
7029 | { | |
7030 | case EQ_EXPR: | |
7031 | return pedantic_non_lvalue (convert (type, arg2)); | |
7032 | case NE_EXPR: | |
7033 | return pedantic_non_lvalue (convert (type, arg1)); | |
7034 | case LE_EXPR: | |
7035 | case LT_EXPR: | |
e9a25f70 JL |
7036 | /* In C++ a ?: expression can be an lvalue, so put the |
7037 | operand which will be used if they are equal first | |
b6cc0a72 | 7038 | so that we can convert this back to the |
e9a25f70 JL |
7039 | corresponding COND_EXPR. */ |
7040 | return pedantic_non_lvalue | |
792a328b JM |
7041 | (convert (type, fold (build (MIN_EXPR, comp_type, |
7042 | (comp_code == LE_EXPR | |
7043 | ? comp_op0 : comp_op1), | |
7044 | (comp_code == LE_EXPR | |
7045 | ? comp_op1 : comp_op0))))); | |
88a5cdb8 | 7046 | break; |
3a96b5eb RK |
7047 | case GE_EXPR: |
7048 | case GT_EXPR: | |
e9a25f70 JL |
7049 | return pedantic_non_lvalue |
7050 | (convert (type, fold (build (MAX_EXPR, comp_type, | |
7051 | (comp_code == GE_EXPR | |
7052 | ? comp_op0 : comp_op1), | |
7053 | (comp_code == GE_EXPR | |
7054 | ? comp_op1 : comp_op0))))); | |
88a5cdb8 | 7055 | break; |
e9a25f70 JL |
7056 | default: |
7057 | abort (); | |
3a96b5eb RK |
7058 | } |
7059 | } | |
c05a9b68 RS |
7060 | |
7061 | /* If this is A op C1 ? A : C2 with C1 and C2 constant integers, | |
7062 | we might still be able to simplify this. For example, | |
7063 | if C1 is one less or one more than C2, this might have started | |
53d2fb4f | 7064 | out as a MIN or MAX and been transformed by this function. |
7178e3af | 7065 | Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */ |
c05a9b68 | 7066 | |
7178e3af | 7067 | if (INTEGRAL_TYPE_P (type) |
53d2fb4f | 7068 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST |
c05a9b68 RS |
7069 | && TREE_CODE (arg2) == INTEGER_CST) |
7070 | switch (comp_code) | |
7071 | { | |
7072 | case EQ_EXPR: | |
7073 | /* We can replace A with C1 in this case. */ | |
cd7ece66 RK |
7074 | arg1 = convert (type, TREE_OPERAND (arg0, 1)); |
7075 | t = build (code, type, TREE_OPERAND (t, 0), arg1, | |
7076 | TREE_OPERAND (t, 2)); | |
c05a9b68 RS |
7077 | break; |
7078 | ||
7079 | case LT_EXPR: | |
7080 | /* If C1 is C2 + 1, this is min(A, C2). */ | |
7081 | if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), 1) | |
7082 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
7083 | const_binop (PLUS_EXPR, arg2, | |
91d33e36 | 7084 | integer_one_node, 0), 1)) |
a5e9b124 JW |
7085 | return pedantic_non_lvalue |
7086 | (fold (build (MIN_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
7087 | break; |
7088 | ||
7089 | case LE_EXPR: | |
7090 | /* If C1 is C2 - 1, this is min(A, C2). */ | |
7091 | if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), 1) | |
7092 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
7093 | const_binop (MINUS_EXPR, arg2, | |
91d33e36 | 7094 | integer_one_node, 0), 1)) |
a5e9b124 JW |
7095 | return pedantic_non_lvalue |
7096 | (fold (build (MIN_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
7097 | break; |
7098 | ||
7099 | case GT_EXPR: | |
7100 | /* If C1 is C2 - 1, this is max(A, C2). */ | |
7101 | if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), 1) | |
7102 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
7103 | const_binop (MINUS_EXPR, arg2, | |
91d33e36 | 7104 | integer_one_node, 0), 1)) |
a5e9b124 JW |
7105 | return pedantic_non_lvalue |
7106 | (fold (build (MAX_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
7107 | break; |
7108 | ||
7109 | case GE_EXPR: | |
7110 | /* If C1 is C2 + 1, this is max(A, C2). */ | |
7111 | if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), 1) | |
7112 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
7113 | const_binop (PLUS_EXPR, arg2, | |
91d33e36 | 7114 | integer_one_node, 0), 1)) |
a5e9b124 JW |
7115 | return pedantic_non_lvalue |
7116 | (fold (build (MAX_EXPR, type, arg1, arg2))); | |
c05a9b68 | 7117 | break; |
e9a25f70 JL |
7118 | case NE_EXPR: |
7119 | break; | |
7120 | default: | |
7121 | abort (); | |
c05a9b68 | 7122 | } |
6d716ca8 RS |
7123 | } |
7124 | ||
e1f56f62 RK |
7125 | /* If the second operand is simpler than the third, swap them |
7126 | since that produces better jump optimization results. */ | |
2f939d94 | 7127 | if ((TREE_CONSTANT (arg1) || DECL_P (arg1) |
e1f56f62 RK |
7128 | || TREE_CODE (arg1) == SAVE_EXPR) |
7129 | && ! (TREE_CONSTANT (TREE_OPERAND (t, 2)) | |
2f939d94 | 7130 | || DECL_P (TREE_OPERAND (t, 2)) |
e1f56f62 RK |
7131 | || TREE_CODE (TREE_OPERAND (t, 2)) == SAVE_EXPR)) |
7132 | { | |
7133 | /* See if this can be inverted. If it can't, possibly because | |
7134 | it was a floating-point inequality comparison, don't do | |
7135 | anything. */ | |
7136 | tem = invert_truthvalue (arg0); | |
7137 | ||
7138 | if (TREE_CODE (tem) != TRUTH_NOT_EXPR) | |
7139 | { | |
cd7ece66 RK |
7140 | t = build (code, type, tem, |
7141 | TREE_OPERAND (t, 2), TREE_OPERAND (t, 1)); | |
7142 | arg0 = tem; | |
c479c2ac JL |
7143 | /* arg1 should be the first argument of the new T. */ |
7144 | arg1 = TREE_OPERAND (t, 1); | |
3a96b5eb | 7145 | STRIP_NOPS (arg1); |
e1f56f62 RK |
7146 | } |
7147 | } | |
7148 | ||
c05a9b68 RS |
7149 | /* Convert A ? 1 : 0 to simply A. */ |
7150 | if (integer_onep (TREE_OPERAND (t, 1)) | |
7151 | && integer_zerop (TREE_OPERAND (t, 2)) | |
7152 | /* If we try to convert TREE_OPERAND (t, 0) to our type, the | |
b6cc0a72 | 7153 | call to fold will try to move the conversion inside |
c05a9b68 RS |
7154 | a COND, which will recurse. In that case, the COND_EXPR |
7155 | is probably the best choice, so leave it alone. */ | |
7156 | && type == TREE_TYPE (arg0)) | |
a5e9b124 | 7157 | return pedantic_non_lvalue (arg0); |
6d716ca8 | 7158 | |
c05a9b68 RS |
7159 | /* Look for expressions of the form A & 2 ? 2 : 0. The result of this |
7160 | operation is simply A & 2. */ | |
6d716ca8 RS |
7161 | |
7162 | if (integer_zerop (TREE_OPERAND (t, 2)) | |
7163 | && TREE_CODE (arg0) == NE_EXPR | |
7164 | && integer_zerop (TREE_OPERAND (arg0, 1)) | |
c05a9b68 RS |
7165 | && integer_pow2p (arg1) |
7166 | && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR | |
7167 | && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1), | |
7168 | arg1, 1)) | |
a5e9b124 | 7169 | return pedantic_non_lvalue (convert (type, TREE_OPERAND (arg0, 0))); |
6d716ca8 | 7170 | |
6d716ca8 RS |
7171 | return t; |
7172 | ||
7173 | case COMPOUND_EXPR: | |
b7647895 JW |
7174 | /* When pedantic, a compound expression can be neither an lvalue |
7175 | nor an integer constant expression. */ | |
7176 | if (TREE_SIDE_EFFECTS (arg0) || pedantic) | |
d023bff9 RS |
7177 | return t; |
7178 | /* Don't let (0, 0) be null pointer constant. */ | |
7179 | if (integer_zerop (arg1)) | |
13eb1f7f RK |
7180 | return build1 (NOP_EXPR, type, arg1); |
7181 | return convert (type, arg1); | |
6d716ca8 | 7182 | |
1cc1b11a RS |
7183 | case COMPLEX_EXPR: |
7184 | if (wins) | |
214d5b84 | 7185 | return build_complex (type, arg0, arg1); |
1cc1b11a RS |
7186 | return t; |
7187 | ||
7188 | case REALPART_EXPR: | |
a333b79f | 7189 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) |
1cc1b11a RS |
7190 | return t; |
7191 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
7192 | return omit_one_operand (type, TREE_OPERAND (arg0, 0), | |
7193 | TREE_OPERAND (arg0, 1)); | |
7194 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
7195 | return TREE_REALPART (arg0); | |
7196 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
a3279355 RK |
7197 | return fold (build (TREE_CODE (arg0), type, |
7198 | fold (build1 (REALPART_EXPR, type, | |
7199 | TREE_OPERAND (arg0, 0))), | |
7200 | fold (build1 (REALPART_EXPR, | |
7201 | type, TREE_OPERAND (arg0, 1))))); | |
1cc1b11a RS |
7202 | return t; |
7203 | ||
7204 | case IMAGPART_EXPR: | |
a333b79f | 7205 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) |
1cc1b11a RS |
7206 | return convert (type, integer_zero_node); |
7207 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
7208 | return omit_one_operand (type, TREE_OPERAND (arg0, 1), | |
7209 | TREE_OPERAND (arg0, 0)); | |
7210 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
7211 | return TREE_IMAGPART (arg0); | |
7212 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
a3279355 RK |
7213 | return fold (build (TREE_CODE (arg0), type, |
7214 | fold (build1 (IMAGPART_EXPR, type, | |
7215 | TREE_OPERAND (arg0, 0))), | |
7216 | fold (build1 (IMAGPART_EXPR, type, | |
7217 | TREE_OPERAND (arg0, 1))))); | |
1cc1b11a RS |
7218 | return t; |
7219 | ||
56c98e5b JM |
7220 | /* Pull arithmetic ops out of the CLEANUP_POINT_EXPR where |
7221 | appropriate. */ | |
7222 | case CLEANUP_POINT_EXPR: | |
b7f6588d | 7223 | if (! has_cleanups (arg0)) |
3ffcb234 | 7224 | return TREE_OPERAND (t, 0); |
56c98e5b JM |
7225 | |
7226 | { | |
7227 | enum tree_code code0 = TREE_CODE (arg0); | |
7228 | int kind0 = TREE_CODE_CLASS (code0); | |
7229 | tree arg00 = TREE_OPERAND (arg0, 0); | |
7230 | tree arg01; | |
7231 | ||
0982a4b8 | 7232 | if (kind0 == '1' || code0 == TRUTH_NOT_EXPR) |
b6cc0a72 | 7233 | return fold (build1 (code0, type, |
56c98e5b JM |
7234 | fold (build1 (CLEANUP_POINT_EXPR, |
7235 | TREE_TYPE (arg00), arg00)))); | |
0982a4b8 JM |
7236 | |
7237 | if (kind0 == '<' || kind0 == '2' | |
7238 | || code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR | |
7239 | || code0 == TRUTH_AND_EXPR || code0 == TRUTH_OR_EXPR | |
7240 | || code0 == TRUTH_XOR_EXPR) | |
7241 | { | |
7242 | arg01 = TREE_OPERAND (arg0, 1); | |
7243 | ||
b7f6588d JM |
7244 | if (TREE_CONSTANT (arg00) |
7245 | || ((code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR) | |
7246 | && ! has_cleanups (arg00))) | |
0982a4b8 JM |
7247 | return fold (build (code0, type, arg00, |
7248 | fold (build1 (CLEANUP_POINT_EXPR, | |
7249 | TREE_TYPE (arg01), arg01)))); | |
7250 | ||
b7f6588d | 7251 | if (TREE_CONSTANT (arg01)) |
0982a4b8 JM |
7252 | return fold (build (code0, type, |
7253 | fold (build1 (CLEANUP_POINT_EXPR, | |
7254 | TREE_TYPE (arg00), arg00)), | |
7255 | arg01)); | |
7256 | } | |
56c98e5b JM |
7257 | |
7258 | return t; | |
7259 | } | |
7260 | ||
b0b3afb2 BS |
7261 | case CALL_EXPR: |
7262 | /* Check for a built-in function. */ | |
7263 | if (TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR | |
7264 | && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (expr, 0), 0)) | |
7265 | == FUNCTION_DECL) | |
7266 | && DECL_BUILT_IN (TREE_OPERAND (TREE_OPERAND (expr, 0), 0))) | |
7267 | { | |
7268 | tree tmp = fold_builtin (expr); | |
7269 | if (tmp) | |
7270 | return tmp; | |
7271 | } | |
7272 | return t; | |
7273 | ||
6d716ca8 RS |
7274 | default: |
7275 | return t; | |
7276 | } /* switch (code) */ | |
7277 | } | |
39dfb55a | 7278 | |
c5c76735 JL |
7279 | /* Determine if first argument is a multiple of second argument. Return 0 if |
7280 | it is not, or we cannot easily determined it to be. | |
39dfb55a | 7281 | |
c5c76735 JL |
7282 | An example of the sort of thing we care about (at this point; this routine |
7283 | could surely be made more general, and expanded to do what the *_DIV_EXPR's | |
7284 | fold cases do now) is discovering that | |
39dfb55a JL |
7285 | |
7286 | SAVE_EXPR (I) * SAVE_EXPR (J * 8) | |
7287 | ||
7288 | is a multiple of | |
7289 | ||
7290 | SAVE_EXPR (J * 8) | |
7291 | ||
c5c76735 | 7292 | when we know that the two SAVE_EXPR (J * 8) nodes are the same node. |
39dfb55a JL |
7293 | |
7294 | This code also handles discovering that | |
7295 | ||
7296 | SAVE_EXPR (I) * SAVE_EXPR (J * 8) | |
7297 | ||
c5c76735 | 7298 | is a multiple of 8 so we don't have to worry about dealing with a |
39dfb55a JL |
7299 | possible remainder. |
7300 | ||
c5c76735 JL |
7301 | Note that we *look* inside a SAVE_EXPR only to determine how it was |
7302 | calculated; it is not safe for fold to do much of anything else with the | |
7303 | internals of a SAVE_EXPR, since it cannot know when it will be evaluated | |
7304 | at run time. For example, the latter example above *cannot* be implemented | |
7305 | as SAVE_EXPR (I) * J or any variant thereof, since the value of J at | |
7306 | evaluation time of the original SAVE_EXPR is not necessarily the same at | |
7307 | the time the new expression is evaluated. The only optimization of this | |
39dfb55a JL |
7308 | sort that would be valid is changing |
7309 | ||
7310 | SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8) | |
39dfb55a | 7311 | |
c5c76735 | 7312 | divided by 8 to |
39dfb55a JL |
7313 | |
7314 | SAVE_EXPR (I) * SAVE_EXPR (J) | |
7315 | ||
7316 | (where the same SAVE_EXPR (J) is used in the original and the | |
7317 | transformed version). */ | |
7318 | ||
7319 | static int | |
7320 | multiple_of_p (type, top, bottom) | |
7321 | tree type; | |
7322 | tree top; | |
7323 | tree bottom; | |
7324 | { | |
7325 | if (operand_equal_p (top, bottom, 0)) | |
7326 | return 1; | |
7327 | ||
7328 | if (TREE_CODE (type) != INTEGER_TYPE) | |
7329 | return 0; | |
7330 | ||
7331 | switch (TREE_CODE (top)) | |
7332 | { | |
7333 | case MULT_EXPR: | |
7334 | return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom) | |
7335 | || multiple_of_p (type, TREE_OPERAND (top, 1), bottom)); | |
7336 | ||
7337 | case PLUS_EXPR: | |
7338 | case MINUS_EXPR: | |
7339 | return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom) | |
7340 | && multiple_of_p (type, TREE_OPERAND (top, 1), bottom)); | |
7341 | ||
fba2c0cd JJ |
7342 | case LSHIFT_EXPR: |
7343 | if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST) | |
7344 | { | |
7345 | tree op1, t1; | |
7346 | ||
7347 | op1 = TREE_OPERAND (top, 1); | |
7348 | /* const_binop may not detect overflow correctly, | |
7349 | so check for it explicitly here. */ | |
7350 | if (TYPE_PRECISION (TREE_TYPE (size_one_node)) | |
7351 | > TREE_INT_CST_LOW (op1) | |
7352 | && TREE_INT_CST_HIGH (op1) == 0 | |
7353 | && 0 != (t1 = convert (type, | |
7354 | const_binop (LSHIFT_EXPR, size_one_node, | |
7355 | op1, 0))) | |
7356 | && ! TREE_OVERFLOW (t1)) | |
7357 | return multiple_of_p (type, t1, bottom); | |
7358 | } | |
7359 | return 0; | |
7360 | ||
39dfb55a | 7361 | case NOP_EXPR: |
c5c76735 | 7362 | /* Can't handle conversions from non-integral or wider integral type. */ |
39dfb55a JL |
7363 | if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE) |
7364 | || (TYPE_PRECISION (type) | |
7365 | < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0))))) | |
7366 | return 0; | |
c5c76735 | 7367 | |
30f7a378 | 7368 | /* .. fall through ... */ |
c5c76735 | 7369 | |
39dfb55a JL |
7370 | case SAVE_EXPR: |
7371 | return multiple_of_p (type, TREE_OPERAND (top, 0), bottom); | |
7372 | ||
7373 | case INTEGER_CST: | |
fba2c0cd JJ |
7374 | if (TREE_CODE (bottom) != INTEGER_CST |
7375 | || (TREE_UNSIGNED (type) | |
7376 | && (tree_int_cst_sgn (top) < 0 | |
7377 | || tree_int_cst_sgn (bottom) < 0))) | |
39dfb55a JL |
7378 | return 0; |
7379 | return integer_zerop (const_binop (TRUNC_MOD_EXPR, | |
7380 | top, bottom, 0)); | |
7381 | ||
7382 | default: | |
7383 | return 0; | |
7384 | } | |
7385 | } | |
a36556a8 ZW |
7386 | |
7387 | /* Return true if `t' is known to be non-negative. */ | |
7388 | ||
7389 | int | |
7390 | tree_expr_nonnegative_p (t) | |
7391 | tree t; | |
7392 | { | |
7393 | switch (TREE_CODE (t)) | |
7394 | { | |
88e3805d KG |
7395 | case ABS_EXPR: |
7396 | case FFS_EXPR: | |
7397 | return 1; | |
a36556a8 ZW |
7398 | case INTEGER_CST: |
7399 | return tree_int_cst_sgn (t) >= 0; | |
7400 | case COND_EXPR: | |
7401 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)) | |
7402 | && tree_expr_nonnegative_p (TREE_OPERAND (t, 2)); | |
88e3805d KG |
7403 | case COMPOUND_EXPR: |
7404 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
7405 | case MIN_EXPR: | |
7406 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)) | |
7407 | && tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
7408 | case MAX_EXPR: | |
7409 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)) | |
7410 | || tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
7411 | case MODIFY_EXPR: | |
7412 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
a36556a8 ZW |
7413 | case BIND_EXPR: |
7414 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
7415 | case RTL_EXPR: | |
7416 | return rtl_expr_nonnegative_p (RTL_EXPR_RTL (t)); | |
7417 | ||
7418 | default: | |
9d2dc7da KG |
7419 | if (truth_value_p (TREE_CODE (t))) |
7420 | /* Truth values evaluate to 0 or 1, which is nonnegative. */ | |
7421 | return 1; | |
7422 | else | |
7423 | /* We don't know sign of `t', so be conservative and return false. */ | |
7424 | return 0; | |
a36556a8 ZW |
7425 | } |
7426 | } | |
7427 | ||
7428 | /* Return true if `r' is known to be non-negative. | |
7429 | Only handles constants at the moment. */ | |
7430 | ||
7431 | int | |
7432 | rtl_expr_nonnegative_p (r) | |
7433 | rtx r; | |
7434 | { | |
7435 | switch (GET_CODE (r)) | |
7436 | { | |
7437 | case CONST_INT: | |
7438 | return INTVAL (r) >= 0; | |
7439 | ||
7440 | case CONST_DOUBLE: | |
7441 | if (GET_MODE (r) == VOIDmode) | |
7442 | return CONST_DOUBLE_HIGH (r) >= 0; | |
7443 | return 0; | |
7444 | ||
7445 | case SYMBOL_REF: | |
7446 | case LABEL_REF: | |
7447 | /* These are always nonnegative. */ | |
7448 | return 1; | |
7449 | ||
7450 | default: | |
7451 | return 0; | |
7452 | } | |
7453 | } |