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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 RS |
4 | |
5 | This file is part of GNU CC. | |
6 | ||
7 | GNU CC is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 2, or (at your option) | |
10 | any later version. | |
11 | ||
12 | GNU CC is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with GNU CC; see the file COPYING. If not, write to | |
a35311b0 RK |
19 | the Free Software Foundation, 59 Temple Place - Suite 330, |
20 | Boston, MA 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 | 47 | #include <setjmp.h> |
6d716ca8 RS |
48 | #include "flags.h" |
49 | #include "tree.h" | |
efe3eb65 | 50 | #include "rtl.h" |
0e9295cf | 51 | #include "expr.h" |
6baf1cc8 | 52 | #include "tm_p.h" |
10f0ad3d | 53 | #include "toplev.h" |
a3770a81 | 54 | #include "ggc.h" |
6d716ca8 | 55 | |
711d877c | 56 | static void encode PARAMS ((HOST_WIDE_INT *, |
05bccae2 RK |
57 | unsigned HOST_WIDE_INT, |
58 | HOST_WIDE_INT)); | |
711d877c | 59 | static void decode PARAMS ((HOST_WIDE_INT *, |
05bccae2 | 60 | unsigned HOST_WIDE_INT *, |
711d877c KG |
61 | HOST_WIDE_INT *)); |
62 | static tree negate_expr PARAMS ((tree)); | |
63 | static tree split_tree PARAMS ((tree, enum tree_code, tree *, tree *, | |
64 | int)); | |
65 | static tree associate_trees PARAMS ((tree, tree, enum tree_code, tree)); | |
66 | static tree int_const_binop PARAMS ((enum tree_code, tree, tree, int, int)); | |
67 | static void const_binop_1 PARAMS ((PTR)); | |
68 | static tree const_binop PARAMS ((enum tree_code, tree, tree, int)); | |
69 | static void fold_convert_1 PARAMS ((PTR)); | |
70 | static tree fold_convert PARAMS ((tree, tree)); | |
71 | static enum tree_code invert_tree_comparison PARAMS ((enum tree_code)); | |
72 | static enum tree_code swap_tree_comparison PARAMS ((enum tree_code)); | |
73 | static int truth_value_p PARAMS ((enum tree_code)); | |
74 | static int operand_equal_for_comparison_p PARAMS ((tree, tree, tree)); | |
75 | static int twoval_comparison_p PARAMS ((tree, tree *, tree *, int *)); | |
76 | static tree eval_subst PARAMS ((tree, tree, tree, tree, tree)); | |
77 | static tree omit_one_operand PARAMS ((tree, tree, tree)); | |
78 | static tree pedantic_omit_one_operand PARAMS ((tree, tree, tree)); | |
79 | static tree distribute_bit_expr PARAMS ((enum tree_code, tree, tree, tree)); | |
80 | static tree make_bit_field_ref PARAMS ((tree, tree, int, int, int)); | |
81 | static tree optimize_bit_field_compare PARAMS ((enum tree_code, tree, | |
82 | tree, tree)); | |
770ae6cc RK |
83 | static tree decode_field_reference PARAMS ((tree, HOST_WIDE_INT *, |
84 | HOST_WIDE_INT *, | |
711d877c KG |
85 | enum machine_mode *, int *, |
86 | int *, tree *, tree *)); | |
87 | static int all_ones_mask_p PARAMS ((tree, int)); | |
88 | static int simple_operand_p PARAMS ((tree)); | |
89 | static tree range_binop PARAMS ((enum tree_code, tree, tree, int, | |
90 | tree, int)); | |
91 | static tree make_range PARAMS ((tree, int *, tree *, tree *)); | |
92 | static tree build_range_check PARAMS ((tree, tree, int, tree, tree)); | |
93 | static int merge_ranges PARAMS ((int *, tree *, tree *, int, tree, tree, | |
ebde8a27 | 94 | int, tree, tree)); |
711d877c KG |
95 | static tree fold_range_test PARAMS ((tree)); |
96 | static tree unextend PARAMS ((tree, int, int, tree)); | |
97 | static tree fold_truthop PARAMS ((enum tree_code, tree, tree, tree)); | |
98 | static tree optimize_minmax_comparison PARAMS ((tree)); | |
99 | static tree extract_muldiv PARAMS ((tree, tree, enum tree_code, tree)); | |
100 | static tree strip_compound_expr PARAMS ((tree, tree)); | |
101 | static int multiple_of_p PARAMS ((tree, tree, tree)); | |
102 | static tree constant_boolean_node PARAMS ((int, tree)); | |
103 | static int count_cond PARAMS ((tree, int)); | |
68626d4f MM |
104 | static tree fold_binary_op_with_conditional_arg |
105 | PARAMS ((enum tree_code, tree, tree, tree, int)); | |
106 | ||
d35357ed RS |
107 | #ifndef BRANCH_COST |
108 | #define BRANCH_COST 1 | |
109 | #endif | |
fe3e8e40 | 110 | |
5f6d3823 DP |
111 | #if defined(HOST_EBCDIC) |
112 | /* bit 8 is significant in EBCDIC */ | |
113 | #define CHARMASK 0xff | |
114 | #else | |
115 | #define CHARMASK 0x7f | |
116 | #endif | |
117 | ||
d4b60170 RK |
118 | /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring |
119 | overflow. Suppose A, B and SUM have the same respective signs as A1, B1, | |
120 | and SUM1. Then this yields nonzero if overflow occurred during the | |
121 | addition. | |
122 | ||
123 | Overflow occurs if A and B have the same sign, but A and SUM differ in | |
124 | sign. Use `^' to test whether signs differ, and `< 0' to isolate the | |
125 | sign. */ | |
126 | #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0) | |
6d716ca8 | 127 | \f |
906c4e36 | 128 | /* To do constant folding on INTEGER_CST nodes requires two-word arithmetic. |
37bdb7e3 | 129 | We do that by representing the two-word integer in 4 words, with only |
d4b60170 RK |
130 | HOST_BITS_PER_WIDE_INT / 2 bits stored in each word, as a positive |
131 | number. The value of the word is LOWPART + HIGHPART * BASE. */ | |
37bdb7e3 TG |
132 | |
133 | #define LOWPART(x) \ | |
d4b60170 | 134 | ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)) - 1)) |
37bdb7e3 | 135 | #define HIGHPART(x) \ |
d4b60170 RK |
136 | ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT / 2) |
137 | #define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT / 2) | |
6d716ca8 | 138 | |
37bdb7e3 | 139 | /* Unpack a two-word integer into 4 words. |
906c4e36 | 140 | LOW and HI are the integer, as two `HOST_WIDE_INT' pieces. |
37bdb7e3 | 141 | WORDS points to the array of HOST_WIDE_INTs. */ |
6d716ca8 RS |
142 | |
143 | static void | |
37bdb7e3 TG |
144 | encode (words, low, hi) |
145 | HOST_WIDE_INT *words; | |
05bccae2 RK |
146 | unsigned HOST_WIDE_INT low; |
147 | HOST_WIDE_INT hi; | |
6d716ca8 | 148 | { |
37bdb7e3 TG |
149 | words[0] = LOWPART (low); |
150 | words[1] = HIGHPART (low); | |
151 | words[2] = LOWPART (hi); | |
152 | words[3] = HIGHPART (hi); | |
6d716ca8 RS |
153 | } |
154 | ||
37bdb7e3 TG |
155 | /* Pack an array of 4 words into a two-word integer. |
156 | WORDS points to the array of words. | |
906c4e36 | 157 | The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */ |
6d716ca8 RS |
158 | |
159 | static void | |
37bdb7e3 TG |
160 | decode (words, low, hi) |
161 | HOST_WIDE_INT *words; | |
05bccae2 RK |
162 | unsigned HOST_WIDE_INT *low; |
163 | HOST_WIDE_INT *hi; | |
6d716ca8 | 164 | { |
d4b60170 RK |
165 | *low = words[0] + words[1] * BASE; |
166 | *hi = words[2] + words[3] * BASE; | |
6d716ca8 RS |
167 | } |
168 | \f | |
d4b60170 RK |
169 | /* Make the integer constant T valid for its type by setting to 0 or 1 all |
170 | the bits in the constant that don't belong in the type. | |
171 | ||
172 | Return 1 if a signed overflow occurs, 0 otherwise. If OVERFLOW is | |
173 | nonzero, a signed overflow has already occurred in calculating T, so | |
174 | propagate it. | |
649ff3b4 RK |
175 | |
176 | Make the real constant T valid for its type by calling CHECK_FLOAT_VALUE, | |
177 | if it exists. */ | |
6d716ca8 | 178 | |
e0f776fb RS |
179 | int |
180 | force_fit_type (t, overflow) | |
6d716ca8 | 181 | tree t; |
e0f776fb | 182 | int overflow; |
6d716ca8 | 183 | { |
05bccae2 RK |
184 | unsigned HOST_WIDE_INT low; |
185 | HOST_WIDE_INT high; | |
186 | unsigned int prec; | |
6d716ca8 | 187 | |
649ff3b4 RK |
188 | if (TREE_CODE (t) == REAL_CST) |
189 | { | |
190 | #ifdef CHECK_FLOAT_VALUE | |
191 | CHECK_FLOAT_VALUE (TYPE_MODE (TREE_TYPE (t)), TREE_REAL_CST (t), | |
192 | overflow); | |
193 | #endif | |
194 | return overflow; | |
195 | } | |
196 | ||
197 | else if (TREE_CODE (t) != INTEGER_CST) | |
ef2bf0c0 RS |
198 | return overflow; |
199 | ||
200 | low = TREE_INT_CST_LOW (t); | |
201 | high = TREE_INT_CST_HIGH (t); | |
42f769c1 | 202 | |
e5e809f4 | 203 | if (POINTER_TYPE_P (TREE_TYPE (t))) |
6d716ca8 | 204 | prec = POINTER_SIZE; |
ef2bf0c0 RS |
205 | else |
206 | prec = TYPE_PRECISION (TREE_TYPE (t)); | |
6d716ca8 RS |
207 | |
208 | /* First clear all bits that are beyond the type's precision. */ | |
209 | ||
906c4e36 | 210 | if (prec == 2 * HOST_BITS_PER_WIDE_INT) |
6d716ca8 | 211 | ; |
906c4e36 | 212 | else if (prec > HOST_BITS_PER_WIDE_INT) |
d4b60170 RK |
213 | TREE_INT_CST_HIGH (t) |
214 | &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT)); | |
6d716ca8 RS |
215 | else |
216 | { | |
217 | TREE_INT_CST_HIGH (t) = 0; | |
906c4e36 | 218 | if (prec < HOST_BITS_PER_WIDE_INT) |
05bccae2 | 219 | TREE_INT_CST_LOW (t) &= ~((unsigned HOST_WIDE_INT) (-1) << prec); |
6d716ca8 RS |
220 | } |
221 | ||
44475138 RK |
222 | /* Unsigned types do not suffer sign extension or overflow unless they |
223 | are a sizetype. */ | |
224 | if (TREE_UNSIGNED (TREE_TYPE (t)) | |
225 | && ! (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE | |
226 | && TYPE_IS_SIZETYPE (TREE_TYPE (t)))) | |
a7a05640 | 227 | return overflow; |
6d716ca8 | 228 | |
e0f776fb RS |
229 | /* If the value's sign bit is set, extend the sign. */ |
230 | if (prec != 2 * HOST_BITS_PER_WIDE_INT | |
906c4e36 | 231 | && (prec > HOST_BITS_PER_WIDE_INT |
05bccae2 RK |
232 | ? 0 != (TREE_INT_CST_HIGH (t) |
233 | & ((HOST_WIDE_INT) 1 | |
234 | << (prec - HOST_BITS_PER_WIDE_INT - 1))) | |
235 | : 0 != (TREE_INT_CST_LOW (t) | |
236 | & ((unsigned HOST_WIDE_INT) 1 << (prec - 1))))) | |
6d716ca8 RS |
237 | { |
238 | /* Value is negative: | |
239 | set to 1 all the bits that are outside this type's precision. */ | |
906c4e36 | 240 | if (prec > HOST_BITS_PER_WIDE_INT) |
d4b60170 RK |
241 | TREE_INT_CST_HIGH (t) |
242 | |= ((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT)); | |
6d716ca8 RS |
243 | else |
244 | { | |
245 | TREE_INT_CST_HIGH (t) = -1; | |
906c4e36 | 246 | if (prec < HOST_BITS_PER_WIDE_INT) |
05bccae2 | 247 | TREE_INT_CST_LOW (t) |= ((unsigned HOST_WIDE_INT) (-1) << prec); |
6d716ca8 RS |
248 | } |
249 | } | |
e0f776fb | 250 | |
d4b60170 | 251 | /* Return nonzero if signed overflow occurred. */ |
e0f776fb RS |
252 | return |
253 | ((overflow | (low ^ TREE_INT_CST_LOW (t)) | (high ^ TREE_INT_CST_HIGH (t))) | |
254 | != 0); | |
6d716ca8 RS |
255 | } |
256 | \f | |
906c4e36 RK |
257 | /* Add two doubleword integers with doubleword result. |
258 | Each argument is given as two `HOST_WIDE_INT' pieces. | |
6d716ca8 | 259 | One argument is L1 and H1; the other, L2 and H2. |
37bdb7e3 | 260 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 261 | |
fe3e8e40 | 262 | int |
6d716ca8 | 263 | add_double (l1, h1, l2, h2, lv, hv) |
05bccae2 RK |
264 | unsigned HOST_WIDE_INT l1, l2; |
265 | HOST_WIDE_INT h1, h2; | |
266 | unsigned HOST_WIDE_INT *lv; | |
267 | HOST_WIDE_INT *hv; | |
6d716ca8 | 268 | { |
05bccae2 RK |
269 | unsigned HOST_WIDE_INT l; |
270 | HOST_WIDE_INT h; | |
6d716ca8 | 271 | |
37bdb7e3 | 272 | l = l1 + l2; |
05bccae2 | 273 | h = h1 + h2 + (l < l1); |
6d716ca8 | 274 | |
37bdb7e3 TG |
275 | *lv = l; |
276 | *hv = h; | |
d4b60170 | 277 | return OVERFLOW_SUM_SIGN (h1, h2, h); |
6d716ca8 RS |
278 | } |
279 | ||
906c4e36 | 280 | /* Negate a doubleword integer with doubleword result. |
fe3e8e40 | 281 | Return nonzero if the operation overflows, assuming it's signed. |
906c4e36 | 282 | The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1. |
37bdb7e3 | 283 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 284 | |
fe3e8e40 | 285 | int |
6d716ca8 | 286 | neg_double (l1, h1, lv, hv) |
05bccae2 RK |
287 | unsigned HOST_WIDE_INT l1; |
288 | HOST_WIDE_INT h1; | |
289 | unsigned HOST_WIDE_INT *lv; | |
290 | HOST_WIDE_INT *hv; | |
6d716ca8 RS |
291 | { |
292 | if (l1 == 0) | |
293 | { | |
294 | *lv = 0; | |
295 | *hv = - h1; | |
e0f776fb | 296 | return (*hv & h1) < 0; |
6d716ca8 RS |
297 | } |
298 | else | |
299 | { | |
b6cc0a72 KH |
300 | *lv = -l1; |
301 | *hv = ~h1; | |
fe3e8e40 | 302 | return 0; |
6d716ca8 RS |
303 | } |
304 | } | |
305 | \f | |
906c4e36 | 306 | /* Multiply two doubleword integers with doubleword result. |
fe3e8e40 | 307 | Return nonzero if the operation overflows, assuming it's signed. |
906c4e36 | 308 | Each argument is given as two `HOST_WIDE_INT' pieces. |
6d716ca8 | 309 | One argument is L1 and H1; the other, L2 and H2. |
37bdb7e3 | 310 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 311 | |
fe3e8e40 | 312 | int |
6d716ca8 | 313 | mul_double (l1, h1, l2, h2, lv, hv) |
05bccae2 RK |
314 | unsigned HOST_WIDE_INT l1, l2; |
315 | HOST_WIDE_INT h1, h2; | |
316 | unsigned HOST_WIDE_INT *lv; | |
317 | HOST_WIDE_INT *hv; | |
6d716ca8 | 318 | { |
37bdb7e3 TG |
319 | HOST_WIDE_INT arg1[4]; |
320 | HOST_WIDE_INT arg2[4]; | |
321 | HOST_WIDE_INT prod[4 * 2]; | |
322 | register unsigned HOST_WIDE_INT carry; | |
6d716ca8 | 323 | register int i, j, k; |
05bccae2 RK |
324 | unsigned HOST_WIDE_INT toplow, neglow; |
325 | HOST_WIDE_INT tophigh, neghigh; | |
6d716ca8 | 326 | |
6d716ca8 RS |
327 | encode (arg1, l1, h1); |
328 | encode (arg2, l2, h2); | |
329 | ||
961192e1 | 330 | memset ((char *) prod, 0, sizeof prod); |
6d716ca8 | 331 | |
37bdb7e3 TG |
332 | for (i = 0; i < 4; i++) |
333 | { | |
334 | carry = 0; | |
335 | for (j = 0; j < 4; j++) | |
336 | { | |
337 | k = i + j; | |
338 | /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */ | |
339 | carry += arg1[i] * arg2[j]; | |
340 | /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */ | |
341 | carry += prod[k]; | |
342 | prod[k] = LOWPART (carry); | |
343 | carry = HIGHPART (carry); | |
344 | } | |
345 | prod[i + 4] = carry; | |
346 | } | |
6d716ca8 | 347 | |
37bdb7e3 | 348 | decode (prod, lv, hv); /* This ignores prod[4] through prod[4*2-1] */ |
fe3e8e40 RS |
349 | |
350 | /* Check for overflow by calculating the top half of the answer in full; | |
351 | it should agree with the low half's sign bit. */ | |
b6cc0a72 | 352 | decode (prod + 4, &toplow, &tophigh); |
fe3e8e40 RS |
353 | if (h1 < 0) |
354 | { | |
355 | neg_double (l2, h2, &neglow, &neghigh); | |
356 | add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh); | |
357 | } | |
358 | if (h2 < 0) | |
359 | { | |
360 | neg_double (l1, h1, &neglow, &neghigh); | |
361 | add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh); | |
362 | } | |
363 | return (*hv < 0 ? ~(toplow & tophigh) : toplow | tophigh) != 0; | |
6d716ca8 RS |
364 | } |
365 | \f | |
906c4e36 | 366 | /* Shift the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 RS |
367 | keeping only PREC bits of result. |
368 | Shift right if COUNT is negative. | |
369 | ARITH nonzero specifies arithmetic shifting; otherwise use logical shift. | |
906c4e36 | 370 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 371 | |
e0f776fb | 372 | void |
6d716ca8 | 373 | lshift_double (l1, h1, count, prec, lv, hv, arith) |
05bccae2 RK |
374 | unsigned HOST_WIDE_INT l1; |
375 | HOST_WIDE_INT h1, count; | |
376 | unsigned int prec; | |
377 | unsigned HOST_WIDE_INT *lv; | |
378 | HOST_WIDE_INT *hv; | |
6d716ca8 RS |
379 | int arith; |
380 | { | |
6d716ca8 RS |
381 | if (count < 0) |
382 | { | |
b6cc0a72 | 383 | rshift_double (l1, h1, -count, prec, lv, hv, arith); |
e0f776fb | 384 | return; |
6d716ca8 | 385 | } |
b6cc0a72 | 386 | |
3d1877b1 RK |
387 | #ifdef SHIFT_COUNT_TRUNCATED |
388 | if (SHIFT_COUNT_TRUNCATED) | |
389 | count %= prec; | |
390 | #endif | |
6d716ca8 | 391 | |
cb0a34c4 JW |
392 | if (count >= 2 * HOST_BITS_PER_WIDE_INT) |
393 | { | |
394 | /* Shifting by the host word size is undefined according to the | |
395 | ANSI standard, so we must handle this as a special case. */ | |
396 | *hv = 0; | |
397 | *lv = 0; | |
398 | } | |
399 | else if (count >= HOST_BITS_PER_WIDE_INT) | |
6d716ca8 | 400 | { |
05bccae2 | 401 | *hv = l1 << (count - HOST_BITS_PER_WIDE_INT); |
37bdb7e3 TG |
402 | *lv = 0; |
403 | } | |
404 | else | |
405 | { | |
406 | *hv = (((unsigned HOST_WIDE_INT) h1 << count) | |
05bccae2 RK |
407 | | (l1 >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1)); |
408 | *lv = l1 << count; | |
6d716ca8 | 409 | } |
6d716ca8 RS |
410 | } |
411 | ||
906c4e36 | 412 | /* Shift the doubleword integer in L1, H1 right by COUNT places |
6d716ca8 RS |
413 | keeping only PREC bits of result. COUNT must be positive. |
414 | ARITH nonzero specifies arithmetic shifting; otherwise use logical shift. | |
906c4e36 | 415 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
416 | |
417 | void | |
418 | rshift_double (l1, h1, count, prec, lv, hv, arith) | |
05bccae2 RK |
419 | unsigned HOST_WIDE_INT l1; |
420 | HOST_WIDE_INT h1, count; | |
421 | unsigned int prec ATTRIBUTE_UNUSED; | |
422 | unsigned HOST_WIDE_INT *lv; | |
423 | HOST_WIDE_INT *hv; | |
6d716ca8 RS |
424 | int arith; |
425 | { | |
37bdb7e3 | 426 | unsigned HOST_WIDE_INT signmask; |
05bccae2 | 427 | |
37bdb7e3 TG |
428 | signmask = (arith |
429 | ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1)) | |
430 | : 0); | |
6d716ca8 | 431 | |
3d1877b1 RK |
432 | #ifdef SHIFT_COUNT_TRUNCATED |
433 | if (SHIFT_COUNT_TRUNCATED) | |
434 | count %= prec; | |
435 | #endif | |
6d716ca8 | 436 | |
cb0a34c4 JW |
437 | if (count >= 2 * HOST_BITS_PER_WIDE_INT) |
438 | { | |
439 | /* Shifting by the host word size is undefined according to the | |
440 | ANSI standard, so we must handle this as a special case. */ | |
441 | *hv = signmask; | |
442 | *lv = signmask; | |
443 | } | |
444 | else if (count >= HOST_BITS_PER_WIDE_INT) | |
6d716ca8 | 445 | { |
37bdb7e3 | 446 | *hv = signmask; |
2fde567e KG |
447 | *lv = ((signmask << (2 * HOST_BITS_PER_WIDE_INT - count - 1) << 1) |
448 | | ((unsigned HOST_WIDE_INT) h1 >> (count - HOST_BITS_PER_WIDE_INT))); | |
37bdb7e3 TG |
449 | } |
450 | else | |
451 | { | |
05bccae2 | 452 | *lv = ((l1 >> count) |
2fde567e KG |
453 | | ((unsigned HOST_WIDE_INT) h1 << (HOST_BITS_PER_WIDE_INT - count - 1) << 1)); |
454 | *hv = ((signmask << (HOST_BITS_PER_WIDE_INT - count)) | |
37bdb7e3 | 455 | | ((unsigned HOST_WIDE_INT) h1 >> count)); |
6d716ca8 | 456 | } |
6d716ca8 RS |
457 | } |
458 | \f | |
37bdb7e3 | 459 | /* Rotate the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 RS |
460 | keeping only PREC bits of result. |
461 | Rotate right if COUNT is negative. | |
906c4e36 | 462 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
463 | |
464 | void | |
465 | lrotate_double (l1, h1, count, prec, lv, hv) | |
05bccae2 RK |
466 | unsigned HOST_WIDE_INT l1; |
467 | HOST_WIDE_INT h1, count; | |
468 | unsigned int prec; | |
469 | unsigned HOST_WIDE_INT *lv; | |
470 | HOST_WIDE_INT *hv; | |
6d716ca8 | 471 | { |
05bccae2 RK |
472 | unsigned HOST_WIDE_INT s1l, s2l; |
473 | HOST_WIDE_INT s1h, s2h; | |
6d716ca8 | 474 | |
4d39710e | 475 | count %= prec; |
6d716ca8 | 476 | if (count < 0) |
4d39710e | 477 | count += prec; |
6d716ca8 | 478 | |
4d39710e RK |
479 | lshift_double (l1, h1, count, prec, &s1l, &s1h, 0); |
480 | rshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0); | |
481 | *lv = s1l | s2l; | |
482 | *hv = s1h | s2h; | |
6d716ca8 RS |
483 | } |
484 | ||
906c4e36 | 485 | /* Rotate the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 | 486 | keeping only PREC bits of result. COUNT must be positive. |
906c4e36 | 487 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
488 | |
489 | void | |
490 | rrotate_double (l1, h1, count, prec, lv, hv) | |
05bccae2 RK |
491 | unsigned HOST_WIDE_INT l1; |
492 | HOST_WIDE_INT h1, count; | |
493 | unsigned int prec; | |
494 | unsigned HOST_WIDE_INT *lv; | |
495 | HOST_WIDE_INT *hv; | |
6d716ca8 | 496 | { |
05bccae2 RK |
497 | unsigned HOST_WIDE_INT s1l, s2l; |
498 | HOST_WIDE_INT s1h, s2h; | |
6d716ca8 | 499 | |
4d39710e RK |
500 | count %= prec; |
501 | if (count < 0) | |
502 | count += prec; | |
6d716ca8 | 503 | |
4d39710e RK |
504 | rshift_double (l1, h1, count, prec, &s1l, &s1h, 0); |
505 | lshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0); | |
506 | *lv = s1l | s2l; | |
507 | *hv = s1h | s2h; | |
6d716ca8 RS |
508 | } |
509 | \f | |
906c4e36 | 510 | /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN |
6d716ca8 RS |
511 | for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM). |
512 | CODE is a tree code for a kind of division, one of | |
513 | TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR | |
514 | or EXACT_DIV_EXPR | |
fe3e8e40 RS |
515 | It controls how the quotient is rounded to a integer. |
516 | Return nonzero if the operation overflows. | |
6d716ca8 RS |
517 | UNS nonzero says do unsigned division. */ |
518 | ||
dbb5b3ce | 519 | int |
6d716ca8 RS |
520 | div_and_round_double (code, uns, |
521 | lnum_orig, hnum_orig, lden_orig, hden_orig, | |
522 | lquo, hquo, lrem, hrem) | |
523 | enum tree_code code; | |
524 | int uns; | |
05bccae2 RK |
525 | unsigned HOST_WIDE_INT lnum_orig; /* num == numerator == dividend */ |
526 | HOST_WIDE_INT hnum_orig; | |
527 | unsigned HOST_WIDE_INT lden_orig; /* den == denominator == divisor */ | |
528 | HOST_WIDE_INT hden_orig; | |
529 | unsigned HOST_WIDE_INT *lquo, *lrem; | |
530 | HOST_WIDE_INT *hquo, *hrem; | |
6d716ca8 RS |
531 | { |
532 | int quo_neg = 0; | |
37bdb7e3 TG |
533 | HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */ |
534 | HOST_WIDE_INT den[4], quo[4]; | |
535 | register int i, j; | |
536 | unsigned HOST_WIDE_INT work; | |
05bccae2 RK |
537 | unsigned HOST_WIDE_INT carry = 0; |
538 | unsigned HOST_WIDE_INT lnum = lnum_orig; | |
b8eb43a2 | 539 | HOST_WIDE_INT hnum = hnum_orig; |
05bccae2 | 540 | unsigned HOST_WIDE_INT lden = lden_orig; |
b8eb43a2 | 541 | HOST_WIDE_INT hden = hden_orig; |
fe3e8e40 | 542 | int overflow = 0; |
6d716ca8 | 543 | |
05bccae2 | 544 | if (hden == 0 && lden == 0) |
956d6950 | 545 | overflow = 1, lden = 1; |
6d716ca8 RS |
546 | |
547 | /* calculate quotient sign and convert operands to unsigned. */ | |
b6cc0a72 | 548 | if (!uns) |
6d716ca8 | 549 | { |
fe3e8e40 | 550 | if (hnum < 0) |
6d716ca8 RS |
551 | { |
552 | quo_neg = ~ quo_neg; | |
fe3e8e40 | 553 | /* (minimum integer) / (-1) is the only overflow case. */ |
05bccae2 RK |
554 | if (neg_double (lnum, hnum, &lnum, &hnum) |
555 | && ((HOST_WIDE_INT) lden & hden) == -1) | |
fe3e8e40 | 556 | overflow = 1; |
6d716ca8 | 557 | } |
b6cc0a72 | 558 | if (hden < 0) |
6d716ca8 RS |
559 | { |
560 | quo_neg = ~ quo_neg; | |
fe3e8e40 | 561 | neg_double (lden, hden, &lden, &hden); |
6d716ca8 RS |
562 | } |
563 | } | |
564 | ||
565 | if (hnum == 0 && hden == 0) | |
566 | { /* single precision */ | |
567 | *hquo = *hrem = 0; | |
88ee2651 | 568 | /* This unsigned division rounds toward zero. */ |
05bccae2 | 569 | *lquo = lnum / lden; |
6d716ca8 RS |
570 | goto finish_up; |
571 | } | |
572 | ||
573 | if (hnum == 0) | |
574 | { /* trivial case: dividend < divisor */ | |
575 | /* hden != 0 already checked. */ | |
576 | *hquo = *lquo = 0; | |
577 | *hrem = hnum; | |
578 | *lrem = lnum; | |
579 | goto finish_up; | |
580 | } | |
581 | ||
961192e1 | 582 | memset ((char *) quo, 0, sizeof quo); |
6d716ca8 | 583 | |
961192e1 JM |
584 | memset ((char *) num, 0, sizeof num); /* to zero 9th element */ |
585 | memset ((char *) den, 0, sizeof den); | |
6d716ca8 | 586 | |
b6cc0a72 | 587 | encode (num, lnum, hnum); |
6d716ca8 RS |
588 | encode (den, lden, hden); |
589 | ||
37bdb7e3 | 590 | /* Special code for when the divisor < BASE. */ |
05bccae2 | 591 | if (hden == 0 && lden < (unsigned HOST_WIDE_INT) BASE) |
37bdb7e3 | 592 | { |
6d716ca8 | 593 | /* hnum != 0 already checked. */ |
37bdb7e3 | 594 | for (i = 4 - 1; i >= 0; i--) |
6d716ca8 | 595 | { |
37bdb7e3 | 596 | work = num[i] + carry * BASE; |
05bccae2 RK |
597 | quo[i] = work / lden; |
598 | carry = work % lden; | |
6d716ca8 RS |
599 | } |
600 | } | |
37bdb7e3 TG |
601 | else |
602 | { | |
603 | /* Full double precision division, | |
604 | with thanks to Don Knuth's "Seminumerical Algorithms". */ | |
05bccae2 RK |
605 | int num_hi_sig, den_hi_sig; |
606 | unsigned HOST_WIDE_INT quo_est, scale; | |
6d716ca8 | 607 | |
05bccae2 | 608 | /* Find the highest non-zero divisor digit. */ |
b6cc0a72 KH |
609 | for (i = 4 - 1;; i--) |
610 | if (den[i] != 0) | |
611 | { | |
612 | den_hi_sig = i; | |
613 | break; | |
614 | } | |
37bdb7e3 | 615 | |
05bccae2 RK |
616 | /* Insure that the first digit of the divisor is at least BASE/2. |
617 | This is required by the quotient digit estimation algorithm. */ | |
6d716ca8 | 618 | |
05bccae2 RK |
619 | scale = BASE / (den[den_hi_sig] + 1); |
620 | if (scale > 1) | |
621 | { /* scale divisor and dividend */ | |
622 | carry = 0; | |
623 | for (i = 0; i <= 4 - 1; i++) | |
624 | { | |
625 | work = (num[i] * scale) + carry; | |
626 | num[i] = LOWPART (work); | |
627 | carry = HIGHPART (work); | |
628 | } | |
6d716ca8 | 629 | |
05bccae2 RK |
630 | num[4] = carry; |
631 | carry = 0; | |
632 | for (i = 0; i <= 4 - 1; i++) | |
633 | { | |
634 | work = (den[i] * scale) + carry; | |
635 | den[i] = LOWPART (work); | |
636 | carry = HIGHPART (work); | |
637 | if (den[i] != 0) den_hi_sig = i; | |
638 | } | |
639 | } | |
6d716ca8 | 640 | |
05bccae2 | 641 | num_hi_sig = 4; |
6d716ca8 | 642 | |
05bccae2 RK |
643 | /* Main loop */ |
644 | for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--) | |
6d716ca8 | 645 | { |
05bccae2 RK |
646 | /* Guess the next quotient digit, quo_est, by dividing the first |
647 | two remaining dividend digits by the high order quotient digit. | |
648 | quo_est is never low and is at most 2 high. */ | |
649 | unsigned HOST_WIDE_INT tmp; | |
650 | ||
651 | num_hi_sig = i + den_hi_sig + 1; | |
652 | work = num[num_hi_sig] * BASE + num[num_hi_sig - 1]; | |
653 | if (num[num_hi_sig] != den[den_hi_sig]) | |
654 | quo_est = work / den[den_hi_sig]; | |
655 | else | |
656 | quo_est = BASE - 1; | |
6d716ca8 | 657 | |
05bccae2 RK |
658 | /* Refine quo_est so it's usually correct, and at most one high. */ |
659 | tmp = work - quo_est * den[den_hi_sig]; | |
660 | if (tmp < BASE | |
661 | && (den[den_hi_sig - 1] * quo_est | |
662 | > (tmp * BASE + num[num_hi_sig - 2]))) | |
663 | quo_est--; | |
6d716ca8 | 664 | |
05bccae2 RK |
665 | /* Try QUO_EST as the quotient digit, by multiplying the |
666 | divisor by QUO_EST and subtracting from the remaining dividend. | |
667 | Keep in mind that QUO_EST is the I - 1st digit. */ | |
668 | ||
669 | carry = 0; | |
6d716ca8 RS |
670 | for (j = 0; j <= den_hi_sig; j++) |
671 | { | |
05bccae2 | 672 | work = quo_est * den[j] + carry; |
37bdb7e3 | 673 | carry = HIGHPART (work); |
05bccae2 | 674 | work = num[i + j] - LOWPART (work); |
37bdb7e3 | 675 | num[i + j] = LOWPART (work); |
05bccae2 | 676 | carry += HIGHPART (work) != 0; |
6d716ca8 | 677 | } |
6d716ca8 | 678 | |
05bccae2 RK |
679 | /* If quo_est was high by one, then num[i] went negative and |
680 | we need to correct things. */ | |
681 | if (num[num_hi_sig] < carry) | |
682 | { | |
683 | quo_est--; | |
684 | carry = 0; /* add divisor back in */ | |
685 | for (j = 0; j <= den_hi_sig; j++) | |
686 | { | |
687 | work = num[i + j] + den[j] + carry; | |
688 | carry = HIGHPART (work); | |
689 | num[i + j] = LOWPART (work); | |
690 | } | |
691 | ||
692 | num [num_hi_sig] += carry; | |
693 | } | |
694 | ||
695 | /* Store the quotient digit. */ | |
696 | quo[i] = quo_est; | |
697 | } | |
6d716ca8 | 698 | } |
6d716ca8 RS |
699 | |
700 | decode (quo, lquo, hquo); | |
701 | ||
702 | finish_up: | |
703 | /* if result is negative, make it so. */ | |
704 | if (quo_neg) | |
705 | neg_double (*lquo, *hquo, lquo, hquo); | |
706 | ||
707 | /* compute trial remainder: rem = num - (quo * den) */ | |
708 | mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem); | |
709 | neg_double (*lrem, *hrem, lrem, hrem); | |
710 | add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem); | |
711 | ||
712 | switch (code) | |
713 | { | |
714 | case TRUNC_DIV_EXPR: | |
715 | case TRUNC_MOD_EXPR: /* round toward zero */ | |
716 | case EXACT_DIV_EXPR: /* for this one, it shouldn't matter */ | |
fe3e8e40 | 717 | return overflow; |
6d716ca8 RS |
718 | |
719 | case FLOOR_DIV_EXPR: | |
720 | case FLOOR_MOD_EXPR: /* round toward negative infinity */ | |
721 | if (quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio < 0 && rem != 0 */ | |
722 | { | |
723 | /* quo = quo - 1; */ | |
906c4e36 RK |
724 | add_double (*lquo, *hquo, (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, |
725 | lquo, hquo); | |
6d716ca8 | 726 | } |
05bccae2 RK |
727 | else |
728 | return overflow; | |
6d716ca8 RS |
729 | break; |
730 | ||
731 | case CEIL_DIV_EXPR: | |
732 | case CEIL_MOD_EXPR: /* round toward positive infinity */ | |
733 | if (!quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio > 0 && rem != 0 */ | |
734 | { | |
906c4e36 RK |
735 | add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0, |
736 | lquo, hquo); | |
6d716ca8 | 737 | } |
05bccae2 RK |
738 | else |
739 | return overflow; | |
6d716ca8 | 740 | break; |
b6cc0a72 | 741 | |
6d716ca8 RS |
742 | case ROUND_DIV_EXPR: |
743 | case ROUND_MOD_EXPR: /* round to closest integer */ | |
744 | { | |
05bccae2 RK |
745 | unsigned HOST_WIDE_INT labs_rem = *lrem; |
746 | HOST_WIDE_INT habs_rem = *hrem; | |
747 | unsigned HOST_WIDE_INT labs_den = lden, ltwice; | |
748 | HOST_WIDE_INT habs_den = hden, htwice; | |
749 | ||
750 | /* Get absolute values */ | |
751 | if (*hrem < 0) | |
752 | neg_double (*lrem, *hrem, &labs_rem, &habs_rem); | |
753 | if (hden < 0) | |
754 | neg_double (lden, hden, &labs_den, &habs_den); | |
755 | ||
756 | /* If (2 * abs (lrem) >= abs (lden)) */ | |
906c4e36 RK |
757 | mul_double ((HOST_WIDE_INT) 2, (HOST_WIDE_INT) 0, |
758 | labs_rem, habs_rem, <wice, &htwice); | |
05bccae2 | 759 | |
906c4e36 RK |
760 | if (((unsigned HOST_WIDE_INT) habs_den |
761 | < (unsigned HOST_WIDE_INT) htwice) | |
762 | || (((unsigned HOST_WIDE_INT) habs_den | |
763 | == (unsigned HOST_WIDE_INT) htwice) | |
05bccae2 | 764 | && (labs_den < ltwice))) |
6d716ca8 RS |
765 | { |
766 | if (*hquo < 0) | |
767 | /* quo = quo - 1; */ | |
906c4e36 RK |
768 | add_double (*lquo, *hquo, |
769 | (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, lquo, hquo); | |
6d716ca8 RS |
770 | else |
771 | /* quo = quo + 1; */ | |
906c4e36 RK |
772 | add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0, |
773 | lquo, hquo); | |
6d716ca8 | 774 | } |
05bccae2 RK |
775 | else |
776 | return overflow; | |
6d716ca8 RS |
777 | } |
778 | break; | |
779 | ||
780 | default: | |
781 | abort (); | |
782 | } | |
783 | ||
784 | /* compute true remainder: rem = num - (quo * den) */ | |
785 | mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem); | |
786 | neg_double (*lrem, *hrem, lrem, hrem); | |
787 | add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem); | |
fe3e8e40 | 788 | return overflow; |
6d716ca8 RS |
789 | } |
790 | \f | |
5008b8ae | 791 | #ifndef REAL_ARITHMETIC |
649ff3b4 RK |
792 | /* Effectively truncate a real value to represent the nearest possible value |
793 | in a narrower mode. The result is actually represented in the same data | |
794 | type as the argument, but its value is usually different. | |
795 | ||
796 | A trap may occur during the FP operations and it is the responsibility | |
797 | of the calling function to have a handler established. */ | |
5352b11a RS |
798 | |
799 | REAL_VALUE_TYPE | |
800 | real_value_truncate (mode, arg) | |
801 | enum machine_mode mode; | |
802 | REAL_VALUE_TYPE arg; | |
803 | { | |
649ff3b4 | 804 | return REAL_VALUE_TRUNCATE (mode, arg); |
5352b11a RS |
805 | } |
806 | ||
6d716ca8 RS |
807 | #if TARGET_FLOAT_FORMAT == IEEE_FLOAT_FORMAT |
808 | ||
809 | /* Check for infinity in an IEEE double precision number. */ | |
810 | ||
811 | int | |
812 | target_isinf (x) | |
813 | REAL_VALUE_TYPE x; | |
814 | { | |
815 | /* The IEEE 64-bit double format. */ | |
816 | union { | |
817 | REAL_VALUE_TYPE d; | |
818 | struct { | |
819 | unsigned sign : 1; | |
820 | unsigned exponent : 11; | |
821 | unsigned mantissa1 : 20; | |
822 | unsigned mantissa2; | |
823 | } little_endian; | |
824 | struct { | |
825 | unsigned mantissa2; | |
826 | unsigned mantissa1 : 20; | |
827 | unsigned exponent : 11; | |
828 | unsigned sign : 1; | |
b6cc0a72 | 829 | } big_endian; |
6d716ca8 RS |
830 | } u; |
831 | ||
832 | u.d = dconstm1; | |
833 | if (u.big_endian.sign == 1) | |
834 | { | |
835 | u.d = x; | |
836 | return (u.big_endian.exponent == 2047 | |
837 | && u.big_endian.mantissa1 == 0 | |
838 | && u.big_endian.mantissa2 == 0); | |
839 | } | |
840 | else | |
841 | { | |
842 | u.d = x; | |
843 | return (u.little_endian.exponent == 2047 | |
844 | && u.little_endian.mantissa1 == 0 | |
845 | && u.little_endian.mantissa2 == 0); | |
846 | } | |
847 | } | |
848 | ||
7d4d4d22 RS |
849 | /* Check whether an IEEE double precision number is a NaN. */ |
850 | ||
851 | int | |
852 | target_isnan (x) | |
853 | REAL_VALUE_TYPE x; | |
854 | { | |
855 | /* The IEEE 64-bit double format. */ | |
856 | union { | |
857 | REAL_VALUE_TYPE d; | |
858 | struct { | |
859 | unsigned sign : 1; | |
860 | unsigned exponent : 11; | |
861 | unsigned mantissa1 : 20; | |
862 | unsigned mantissa2; | |
863 | } little_endian; | |
864 | struct { | |
865 | unsigned mantissa2; | |
866 | unsigned mantissa1 : 20; | |
867 | unsigned exponent : 11; | |
868 | unsigned sign : 1; | |
b6cc0a72 | 869 | } big_endian; |
7d4d4d22 RS |
870 | } u; |
871 | ||
872 | u.d = dconstm1; | |
873 | if (u.big_endian.sign == 1) | |
874 | { | |
875 | u.d = x; | |
876 | return (u.big_endian.exponent == 2047 | |
877 | && (u.big_endian.mantissa1 != 0 | |
878 | || u.big_endian.mantissa2 != 0)); | |
879 | } | |
880 | else | |
881 | { | |
882 | u.d = x; | |
883 | return (u.little_endian.exponent == 2047 | |
884 | && (u.little_endian.mantissa1 != 0 | |
885 | || u.little_endian.mantissa2 != 0)); | |
886 | } | |
887 | } | |
888 | ||
c05a9b68 | 889 | /* Check for a negative IEEE double precision number. */ |
6d716ca8 RS |
890 | |
891 | int | |
c05a9b68 | 892 | target_negative (x) |
6d716ca8 RS |
893 | REAL_VALUE_TYPE x; |
894 | { | |
c05a9b68 RS |
895 | /* The IEEE 64-bit double format. */ |
896 | union { | |
897 | REAL_VALUE_TYPE d; | |
898 | struct { | |
899 | unsigned sign : 1; | |
900 | unsigned exponent : 11; | |
901 | unsigned mantissa1 : 20; | |
902 | unsigned mantissa2; | |
903 | } little_endian; | |
904 | struct { | |
905 | unsigned mantissa2; | |
906 | unsigned mantissa1 : 20; | |
907 | unsigned exponent : 11; | |
908 | unsigned sign : 1; | |
b6cc0a72 | 909 | } big_endian; |
c05a9b68 | 910 | } u; |
6d716ca8 | 911 | |
c05a9b68 RS |
912 | u.d = dconstm1; |
913 | if (u.big_endian.sign == 1) | |
914 | { | |
915 | u.d = x; | |
916 | return u.big_endian.sign; | |
917 | } | |
918 | else | |
919 | { | |
920 | u.d = x; | |
921 | return u.little_endian.sign; | |
922 | } | |
6d716ca8 RS |
923 | } |
924 | #else /* Target not IEEE */ | |
925 | ||
926 | /* Let's assume other float formats don't have infinity. | |
927 | (This can be overridden by redefining REAL_VALUE_ISINF.) */ | |
928 | ||
7762d54e | 929 | int |
6d716ca8 | 930 | target_isinf (x) |
962f1324 | 931 | REAL_VALUE_TYPE x ATTRIBUTE_UNUSED; |
6d716ca8 RS |
932 | { |
933 | return 0; | |
934 | } | |
935 | ||
7d4d4d22 RS |
936 | /* Let's assume other float formats don't have NaNs. |
937 | (This can be overridden by redefining REAL_VALUE_ISNAN.) */ | |
938 | ||
7762d54e | 939 | int |
7d4d4d22 | 940 | target_isnan (x) |
962f1324 | 941 | REAL_VALUE_TYPE x ATTRIBUTE_UNUSED; |
7d4d4d22 RS |
942 | { |
943 | return 0; | |
944 | } | |
945 | ||
6d716ca8 | 946 | /* Let's assume other float formats don't have minus zero. |
c05a9b68 | 947 | (This can be overridden by redefining REAL_VALUE_NEGATIVE.) */ |
6d716ca8 | 948 | |
7762d54e | 949 | int |
c05a9b68 | 950 | target_negative (x) |
6d716ca8 RS |
951 | REAL_VALUE_TYPE x; |
952 | { | |
c05a9b68 | 953 | return x < 0; |
6d716ca8 RS |
954 | } |
955 | #endif /* Target not IEEE */ | |
39647dcb RK |
956 | |
957 | /* Try to change R into its exact multiplicative inverse in machine mode | |
958 | MODE. Return nonzero function value if successful. */ | |
959 | ||
960 | int | |
961 | exact_real_inverse (mode, r) | |
962 | enum machine_mode mode; | |
963 | REAL_VALUE_TYPE *r; | |
964 | { | |
a4d3481d | 965 | jmp_buf float_error; |
39647dcb RK |
966 | union |
967 | { | |
968 | double d; | |
969 | unsigned short i[4]; | |
970 | }x, t, y; | |
7bdb32b9 | 971 | #ifdef CHECK_FLOAT_VALUE |
39647dcb | 972 | int i; |
7bdb32b9 | 973 | #endif |
39647dcb RK |
974 | |
975 | /* Usually disable if bounds checks are not reliable. */ | |
976 | if ((HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT) && !flag_pretend_float) | |
977 | return 0; | |
978 | ||
979 | /* Set array index to the less significant bits in the unions, depending | |
980 | on the endian-ness of the host doubles. | |
981 | Disable if insufficient information on the data structure. */ | |
982 | #if HOST_FLOAT_FORMAT == UNKNOWN_FLOAT_FORMAT | |
983 | return 0; | |
984 | #else | |
985 | #if HOST_FLOAT_FORMAT == VAX_FLOAT_FORMAT | |
986 | #define K 2 | |
987 | #else | |
988 | #if HOST_FLOAT_FORMAT == IBM_FLOAT_FORMAT | |
989 | #define K 2 | |
990 | #else | |
991 | #define K (2 * HOST_FLOAT_WORDS_BIG_ENDIAN) | |
992 | #endif | |
993 | #endif | |
994 | #endif | |
995 | ||
996 | if (setjmp (float_error)) | |
997 | { | |
998 | /* Don't do the optimization if there was an arithmetic error. */ | |
999 | fail: | |
6496a589 | 1000 | set_float_handler (NULL); |
39647dcb RK |
1001 | return 0; |
1002 | } | |
1003 | set_float_handler (float_error); | |
1004 | ||
1005 | /* Domain check the argument. */ | |
1006 | x.d = *r; | |
1007 | if (x.d == 0.0) | |
1008 | goto fail; | |
1009 | ||
1010 | #ifdef REAL_INFINITY | |
1011 | if (REAL_VALUE_ISINF (x.d) || REAL_VALUE_ISNAN (x.d)) | |
1012 | goto fail; | |
1013 | #endif | |
1014 | ||
1015 | /* Compute the reciprocal and check for numerical exactness. | |
1016 | It is unnecessary to check all the significand bits to determine | |
1017 | whether X is a power of 2. If X is not, then it is impossible for | |
1018 | the bottom half significand of both X and 1/X to be all zero bits. | |
1019 | Hence we ignore the data structure of the top half and examine only | |
1020 | the low order bits of the two significands. */ | |
1021 | t.d = 1.0 / x.d; | |
1022 | if (x.i[K] != 0 || x.i[K + 1] != 0 || t.i[K] != 0 || t.i[K + 1] != 0) | |
1023 | goto fail; | |
1024 | ||
1025 | /* Truncate to the required mode and range-check the result. */ | |
1026 | y.d = REAL_VALUE_TRUNCATE (mode, t.d); | |
1027 | #ifdef CHECK_FLOAT_VALUE | |
1028 | i = 0; | |
1029 | if (CHECK_FLOAT_VALUE (mode, y.d, i)) | |
1030 | goto fail; | |
1031 | #endif | |
1032 | ||
1033 | /* Fail if truncation changed the value. */ | |
1034 | if (y.d != t.d || y.d == 0.0) | |
1035 | goto fail; | |
1036 | ||
1037 | #ifdef REAL_INFINITY | |
1038 | if (REAL_VALUE_ISINF (y.d) || REAL_VALUE_ISNAN (y.d)) | |
1039 | goto fail; | |
1040 | #endif | |
1041 | ||
1042 | /* Output the reciprocal and return success flag. */ | |
6496a589 | 1043 | set_float_handler (NULL); |
39647dcb RK |
1044 | *r = y.d; |
1045 | return 1; | |
1046 | } | |
6f4d7222 | 1047 | |
526aba28 | 1048 | /* Convert C99 hexadecimal floating point string constant S. Return |
6f4d7222 | 1049 | real value type in mode MODE. This function uses the host computer's |
d4b60170 | 1050 | floating point arithmetic when there is no REAL_ARITHMETIC. */ |
6f4d7222 UD |
1051 | |
1052 | REAL_VALUE_TYPE | |
1053 | real_hex_to_f (s, mode) | |
1054 | char *s; | |
1055 | enum machine_mode mode; | |
1056 | { | |
b6cc0a72 KH |
1057 | REAL_VALUE_TYPE ip; |
1058 | char *p = s; | |
1059 | unsigned HOST_WIDE_INT low, high; | |
1060 | int shcount, nrmcount, k; | |
1061 | int sign, expsign, isfloat; | |
1062 | int lost = 0;/* Nonzero low order bits shifted out and discarded. */ | |
1063 | int frexpon = 0; /* Bits after the decimal point. */ | |
1064 | int expon = 0; /* Value of exponent. */ | |
1065 | int decpt = 0; /* How many decimal points. */ | |
1066 | int gotp = 0; /* How many P's. */ | |
1067 | char c; | |
1068 | ||
1069 | isfloat = 0; | |
1070 | expsign = 1; | |
1071 | ip = 0.0; | |
1072 | ||
1073 | while (*p == ' ' || *p == '\t') | |
1074 | ++p; | |
1075 | ||
1076 | /* Sign, if any, comes first. */ | |
1077 | sign = 1; | |
1078 | if (*p == '-') | |
1079 | { | |
1080 | sign = -1; | |
1081 | ++p; | |
1082 | } | |
1083 | ||
1084 | /* The string is supposed to start with 0x or 0X . */ | |
1085 | if (*p == '0') | |
1086 | { | |
1087 | ++p; | |
1088 | if (*p == 'x' || *p == 'X') | |
1089 | ++p; | |
1090 | else | |
1091 | abort (); | |
1092 | } | |
1093 | else | |
1094 | abort (); | |
1095 | ||
1096 | while (*p == '0') | |
1097 | ++p; | |
1098 | ||
1099 | high = 0; | |
1100 | low = 0; | |
1101 | shcount = 0; | |
1102 | while ((c = *p) != '\0') | |
1103 | { | |
1104 | if ((c >= '0' && c <= '9') || (c >= 'A' && c <= 'F') | |
1105 | || (c >= 'a' && c <= 'f')) | |
1106 | { | |
1107 | k = c & CHARMASK; | |
1108 | if (k >= 'a' && k <= 'f') | |
1109 | k = k - 'a' + 10; | |
1110 | else if (k >= 'A') | |
1111 | k = k - 'A' + 10; | |
1112 | else | |
1113 | k = k - '0'; | |
1114 | ||
1115 | if ((high & 0xf0000000) == 0) | |
1116 | { | |
1117 | high = (high << 4) + ((low >> 28) & 15); | |
1118 | low = (low << 4) + k; | |
1119 | shcount += 4; | |
1120 | if (decpt) | |
1121 | frexpon += 4; | |
1122 | } | |
1123 | else | |
1124 | { | |
1125 | /* Record nonzero lost bits. */ | |
1126 | lost |= k; | |
1127 | if (! decpt) | |
1128 | frexpon -= 4; | |
1129 | } | |
1130 | ++p; | |
1131 | } | |
1132 | else if (c == '.') | |
1133 | { | |
1134 | ++decpt; | |
1135 | ++p; | |
1136 | } | |
1137 | ||
1138 | else if (c == 'p' || c == 'P') | |
1139 | { | |
1140 | ++gotp; | |
1141 | ++p; | |
1142 | /* Sign of exponent. */ | |
1143 | if (*p == '-') | |
1144 | { | |
1145 | expsign = -1; | |
1146 | ++p; | |
1147 | } | |
1148 | ||
1149 | /* Value of exponent. | |
1150 | The exponent field is a decimal integer. */ | |
1151 | while (ISDIGIT (*p)) | |
1152 | { | |
1153 | k = (*p++ & CHARMASK) - '0'; | |
1154 | expon = 10 * expon + k; | |
1155 | } | |
1156 | ||
1157 | expon *= expsign; | |
1158 | /* F suffix is ambiguous in the significand part | |
1159 | so it must appear after the decimal exponent field. */ | |
1160 | if (*p == 'f' || *p == 'F') | |
1161 | { | |
1162 | isfloat = 1; | |
1163 | ++p; | |
1164 | break; | |
1165 | } | |
1166 | } | |
1167 | ||
1168 | else if (c == 'l' || c == 'L') | |
1169 | { | |
1170 | ++p; | |
1171 | break; | |
1172 | } | |
1173 | else | |
1174 | break; | |
1175 | } | |
1176 | ||
1177 | /* Abort if last character read was not legitimate. */ | |
1178 | c = *p; | |
1179 | if ((c != '\0' && c != ' ' && c != '\n' && c != '\r') || (decpt > 1)) | |
1180 | abort (); | |
1181 | ||
1182 | /* There must be either one decimal point or one p. */ | |
1183 | if (decpt == 0 && gotp == 0) | |
1184 | abort (); | |
1185 | ||
1186 | shcount -= 4; | |
1187 | if (high == 0 && low == 0) | |
1188 | return dconst0; | |
1189 | ||
1190 | /* Normalize. */ | |
1191 | nrmcount = 0; | |
1192 | if (high == 0) | |
1193 | { | |
1194 | high = low; | |
1195 | low = 0; | |
1196 | nrmcount += 32; | |
1197 | } | |
1198 | ||
1199 | /* Leave a high guard bit for carry-out. */ | |
1200 | if ((high & 0x80000000) != 0) | |
1201 | { | |
1202 | lost |= low & 1; | |
1203 | low = (low >> 1) | (high << 31); | |
1204 | high = high >> 1; | |
1205 | nrmcount -= 1; | |
1206 | } | |
1207 | ||
1208 | if ((high & 0xffff8000) == 0) | |
1209 | { | |
1210 | high = (high << 16) + ((low >> 16) & 0xffff); | |
1211 | low = low << 16; | |
1212 | nrmcount += 16; | |
1213 | } | |
1214 | ||
1215 | while ((high & 0xc0000000) == 0) | |
1216 | { | |
1217 | high = (high << 1) + ((low >> 31) & 1); | |
1218 | low = low << 1; | |
1219 | nrmcount += 1; | |
1220 | } | |
1221 | ||
1222 | if (isfloat || GET_MODE_SIZE (mode) == UNITS_PER_WORD) | |
1223 | { | |
1224 | /* Keep 24 bits precision, bits 0x7fffff80. | |
1225 | Rounding bit is 0x40. */ | |
1226 | lost = lost | low | (high & 0x3f); | |
1227 | low = 0; | |
1228 | if (high & 0x40) | |
1229 | { | |
1230 | if ((high & 0x80) || lost) | |
1231 | high += 0x40; | |
1232 | } | |
1233 | high &= 0xffffff80; | |
1234 | } | |
1235 | else | |
1236 | { | |
1237 | /* We need real.c to do long double formats, so here default | |
1238 | to double precision. */ | |
6f4d7222 | 1239 | #if HOST_FLOAT_FORMAT == IEEE_FLOAT_FORMAT |
b6cc0a72 KH |
1240 | /* IEEE double. |
1241 | Keep 53 bits precision, bits 0x7fffffff fffffc00. | |
1242 | Rounding bit is low word 0x200. */ | |
1243 | lost = lost | (low & 0x1ff); | |
1244 | if (low & 0x200) | |
1245 | { | |
1246 | if ((low & 0x400) || lost) | |
1247 | { | |
1248 | low = (low + 0x200) & 0xfffffc00; | |
1249 | if (low == 0) | |
1250 | high += 1; | |
1251 | } | |
1252 | } | |
1253 | low &= 0xfffffc00; | |
6f4d7222 | 1254 | #else |
b6cc0a72 KH |
1255 | /* Assume it's a VAX with 56-bit significand, |
1256 | bits 0x7fffffff ffffff80. */ | |
1257 | lost = lost | (low & 0x7f); | |
1258 | if (low & 0x40) | |
1259 | { | |
1260 | if ((low & 0x80) || lost) | |
1261 | { | |
1262 | low = (low + 0x40) & 0xffffff80; | |
1263 | if (low == 0) | |
1264 | high += 1; | |
1265 | } | |
1266 | } | |
1267 | low &= 0xffffff80; | |
6f4d7222 | 1268 | #endif |
b6cc0a72 | 1269 | } |
d4b60170 | 1270 | |
b6cc0a72 KH |
1271 | ip = (double) high; |
1272 | ip = REAL_VALUE_LDEXP (ip, 32) + (double) low; | |
1273 | /* Apply shifts and exponent value as power of 2. */ | |
1274 | ip = REAL_VALUE_LDEXP (ip, expon - (nrmcount + frexpon)); | |
6f4d7222 | 1275 | |
b6cc0a72 KH |
1276 | if (sign < 0) |
1277 | ip = -ip; | |
1278 | return ip; | |
6f4d7222 UD |
1279 | } |
1280 | ||
5008b8ae | 1281 | #endif /* no REAL_ARITHMETIC */ |
6d716ca8 | 1282 | \f |
1baa375f RK |
1283 | /* Given T, an expression, return the negation of T. Allow for T to be |
1284 | null, in which case return null. */ | |
6d716ca8 | 1285 | |
1baa375f RK |
1286 | static tree |
1287 | negate_expr (t) | |
1288 | tree t; | |
1289 | { | |
1290 | tree type; | |
1291 | tree tem; | |
1292 | ||
1293 | if (t == 0) | |
1294 | return 0; | |
1295 | ||
1296 | type = TREE_TYPE (t); | |
1297 | STRIP_SIGN_NOPS (t); | |
1298 | ||
1299 | switch (TREE_CODE (t)) | |
1300 | { | |
1301 | case INTEGER_CST: | |
1302 | case REAL_CST: | |
1303 | if (! TREE_UNSIGNED (type) | |
1304 | && 0 != (tem = fold (build1 (NEGATE_EXPR, type, t))) | |
1305 | && ! TREE_OVERFLOW (tem)) | |
1306 | return tem; | |
1307 | break; | |
1308 | ||
1309 | case NEGATE_EXPR: | |
1310 | return convert (type, TREE_OPERAND (t, 0)); | |
1311 | ||
1312 | case MINUS_EXPR: | |
1313 | /* - (A - B) -> B - A */ | |
de6c5979 | 1314 | if (! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations) |
1baa375f RK |
1315 | return convert (type, |
1316 | fold (build (MINUS_EXPR, TREE_TYPE (t), | |
1317 | TREE_OPERAND (t, 1), | |
1318 | TREE_OPERAND (t, 0)))); | |
1319 | break; | |
1320 | ||
1321 | default: | |
1322 | break; | |
1323 | } | |
1324 | ||
1325 | return convert (type, build1 (NEGATE_EXPR, TREE_TYPE (t), t)); | |
1326 | } | |
1327 | \f | |
1328 | /* Split a tree IN into a constant, literal and variable parts that could be | |
1329 | combined with CODE to make IN. "constant" means an expression with | |
1330 | TREE_CONSTANT but that isn't an actual constant. CODE must be a | |
1331 | commutative arithmetic operation. Store the constant part into *CONP, | |
1332 | the literal in &LITP and return the variable part. If a part isn't | |
1333 | present, set it to null. If the tree does not decompose in this way, | |
1334 | return the entire tree as the variable part and the other parts as null. | |
1335 | ||
1336 | If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that | |
1337 | case, we negate an operand that was subtracted. If NEGATE_P is true, we | |
1338 | are negating all of IN. | |
1339 | ||
1340 | If IN is itself a literal or constant, return it as appropriate. | |
1341 | ||
1342 | Note that we do not guarantee that any of the three values will be the | |
1343 | same type as IN, but they will have the same signedness and mode. */ | |
1344 | ||
1345 | static tree | |
1346 | split_tree (in, code, conp, litp, negate_p) | |
6d716ca8 RS |
1347 | tree in; |
1348 | enum tree_code code; | |
1baa375f RK |
1349 | tree *conp, *litp; |
1350 | int negate_p; | |
6d716ca8 | 1351 | { |
1baa375f RK |
1352 | tree var = 0; |
1353 | ||
6d716ca8 | 1354 | *conp = 0; |
1baa375f RK |
1355 | *litp = 0; |
1356 | ||
1357 | /* Strip any conversions that don't change the machine mode or signedness. */ | |
1358 | STRIP_SIGN_NOPS (in); | |
1359 | ||
1360 | if (TREE_CODE (in) == INTEGER_CST || TREE_CODE (in) == REAL_CST) | |
1361 | *litp = in; | |
1baa375f RK |
1362 | else if (TREE_CODE (in) == code |
1363 | || (! FLOAT_TYPE_P (TREE_TYPE (in)) | |
1364 | /* We can associate addition and subtraction together (even | |
1365 | though the C standard doesn't say so) for integers because | |
1366 | the value is not affected. For reals, the value might be | |
1367 | affected, so we can't. */ | |
1368 | && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR) | |
1369 | || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR)))) | |
1370 | { | |
1371 | tree op0 = TREE_OPERAND (in, 0); | |
1372 | tree op1 = TREE_OPERAND (in, 1); | |
1373 | int neg1_p = TREE_CODE (in) == MINUS_EXPR; | |
1374 | int neg_litp_p = 0, neg_conp_p = 0, neg_var_p = 0; | |
1375 | ||
1376 | /* First see if either of the operands is a literal, then a constant. */ | |
1377 | if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST) | |
1378 | *litp = op0, op0 = 0; | |
1379 | else if (TREE_CODE (op1) == INTEGER_CST || TREE_CODE (op1) == REAL_CST) | |
1380 | *litp = op1, neg_litp_p = neg1_p, op1 = 0; | |
1381 | ||
1382 | if (op0 != 0 && TREE_CONSTANT (op0)) | |
1383 | *conp = op0, op0 = 0; | |
1384 | else if (op1 != 0 && TREE_CONSTANT (op1)) | |
1385 | *conp = op1, neg_conp_p = neg1_p, op1 = 0; | |
1386 | ||
1387 | /* If we haven't dealt with either operand, this is not a case we can | |
1388 | decompose. Otherwise, VAR is either of the ones remaining, if any. */ | |
1389 | if (op0 != 0 && op1 != 0) | |
1390 | var = in; | |
1391 | else if (op0 != 0) | |
1392 | var = op0; | |
1393 | else | |
1394 | var = op1, neg_var_p = neg1_p; | |
6d716ca8 | 1395 | |
1baa375f RK |
1396 | /* Now do any needed negations. */ |
1397 | if (neg_litp_p) *litp = negate_expr (*litp); | |
1398 | if (neg_conp_p) *conp = negate_expr (*conp); | |
1399 | if (neg_var_p) var = negate_expr (var); | |
1400 | } | |
1796dff4 RH |
1401 | else if (TREE_CONSTANT (in)) |
1402 | *conp = in; | |
1baa375f RK |
1403 | else |
1404 | var = in; | |
1405 | ||
1406 | if (negate_p) | |
6d716ca8 | 1407 | { |
1baa375f RK |
1408 | var = negate_expr (var); |
1409 | *conp = negate_expr (*conp); | |
1410 | *litp = negate_expr (*litp); | |
6d716ca8 | 1411 | } |
1baa375f RK |
1412 | |
1413 | return var; | |
1414 | } | |
1415 | ||
1416 | /* Re-associate trees split by the above function. T1 and T2 are either | |
1417 | expressions to associate or null. Return the new expression, if any. If | |
1418 | we build an operation, do it in TYPE and with CODE, except if CODE is a | |
1419 | MINUS_EXPR, in which case we use PLUS_EXPR since split_tree will already | |
1420 | have taken care of the negations. */ | |
1421 | ||
1422 | static tree | |
1423 | associate_trees (t1, t2, code, type) | |
1424 | tree t1, t2; | |
1425 | enum tree_code code; | |
1426 | tree type; | |
1427 | { | |
1baa375f RK |
1428 | if (t1 == 0) |
1429 | return t2; | |
1430 | else if (t2 == 0) | |
1431 | return t1; | |
1432 | ||
1433 | if (code == MINUS_EXPR) | |
1434 | code = PLUS_EXPR; | |
1435 | ||
1436 | /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't | |
1437 | try to fold this since we will have infinite recursion. But do | |
1438 | deal with any NEGATE_EXPRs. */ | |
1439 | if (TREE_CODE (t1) == code || TREE_CODE (t2) == code | |
1440 | || TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR) | |
1441 | { | |
1442 | if (TREE_CODE (t1) == NEGATE_EXPR) | |
1443 | return build (MINUS_EXPR, type, convert (type, t2), | |
1444 | convert (type, TREE_OPERAND (t1, 0))); | |
1445 | else if (TREE_CODE (t2) == NEGATE_EXPR) | |
1446 | return build (MINUS_EXPR, type, convert (type, t1), | |
1447 | convert (type, TREE_OPERAND (t2, 0))); | |
1448 | else | |
1449 | return build (code, type, convert (type, t1), convert (type, t2)); | |
1450 | } | |
1451 | ||
1452 | return fold (build (code, type, convert (type, t1), convert (type, t2))); | |
6d716ca8 RS |
1453 | } |
1454 | \f | |
e9a25f70 | 1455 | /* Combine two integer constants ARG1 and ARG2 under operation CODE |
6d716ca8 | 1456 | to produce a new constant. |
91d33e36 | 1457 | |
e9a25f70 JL |
1458 | If NOTRUNC is nonzero, do not truncate the result to fit the data type. |
1459 | If FORSIZE is nonzero, compute overflow for unsigned types. */ | |
6d716ca8 | 1460 | |
6d716ca8 | 1461 | static tree |
e9a25f70 | 1462 | int_const_binop (code, arg1, arg2, notrunc, forsize) |
6d716ca8 RS |
1463 | enum tree_code code; |
1464 | register tree arg1, arg2; | |
e9a25f70 | 1465 | int notrunc, forsize; |
6d716ca8 | 1466 | { |
05bccae2 RK |
1467 | unsigned HOST_WIDE_INT int1l, int2l; |
1468 | HOST_WIDE_INT int1h, int2h; | |
1469 | unsigned HOST_WIDE_INT low; | |
1470 | HOST_WIDE_INT hi; | |
1471 | unsigned HOST_WIDE_INT garbagel; | |
1472 | HOST_WIDE_INT garbageh; | |
e9a25f70 JL |
1473 | register tree t; |
1474 | int uns = TREE_UNSIGNED (TREE_TYPE (arg1)); | |
1475 | int overflow = 0; | |
1476 | int no_overflow = 0; | |
3dedc65a | 1477 | |
e9a25f70 JL |
1478 | int1l = TREE_INT_CST_LOW (arg1); |
1479 | int1h = TREE_INT_CST_HIGH (arg1); | |
1480 | int2l = TREE_INT_CST_LOW (arg2); | |
1481 | int2h = TREE_INT_CST_HIGH (arg2); | |
1482 | ||
1483 | switch (code) | |
6d716ca8 | 1484 | { |
e9a25f70 JL |
1485 | case BIT_IOR_EXPR: |
1486 | low = int1l | int2l, hi = int1h | int2h; | |
1487 | break; | |
6d716ca8 | 1488 | |
e9a25f70 JL |
1489 | case BIT_XOR_EXPR: |
1490 | low = int1l ^ int2l, hi = int1h ^ int2h; | |
1491 | break; | |
6d716ca8 | 1492 | |
e9a25f70 JL |
1493 | case BIT_AND_EXPR: |
1494 | low = int1l & int2l, hi = int1h & int2h; | |
1495 | break; | |
6d716ca8 | 1496 | |
e9a25f70 JL |
1497 | case BIT_ANDTC_EXPR: |
1498 | low = int1l & ~int2l, hi = int1h & ~int2h; | |
1499 | break; | |
6d716ca8 | 1500 | |
e9a25f70 | 1501 | case RSHIFT_EXPR: |
b6cc0a72 | 1502 | int2l = -int2l; |
e9a25f70 JL |
1503 | case LSHIFT_EXPR: |
1504 | /* It's unclear from the C standard whether shifts can overflow. | |
1505 | The following code ignores overflow; perhaps a C standard | |
1506 | interpretation ruling is needed. */ | |
770ae6cc RK |
1507 | lshift_double (int1l, int1h, int2l, TYPE_PRECISION (TREE_TYPE (arg1)), |
1508 | &low, &hi, !uns); | |
e9a25f70 JL |
1509 | no_overflow = 1; |
1510 | break; | |
6d716ca8 | 1511 | |
e9a25f70 JL |
1512 | case RROTATE_EXPR: |
1513 | int2l = - int2l; | |
1514 | case LROTATE_EXPR: | |
770ae6cc | 1515 | lrotate_double (int1l, int1h, int2l, TYPE_PRECISION (TREE_TYPE (arg1)), |
e9a25f70 JL |
1516 | &low, &hi); |
1517 | break; | |
6d716ca8 | 1518 | |
e9a25f70 JL |
1519 | case PLUS_EXPR: |
1520 | overflow = add_double (int1l, int1h, int2l, int2h, &low, &hi); | |
1521 | break; | |
6d716ca8 | 1522 | |
e9a25f70 JL |
1523 | case MINUS_EXPR: |
1524 | neg_double (int2l, int2h, &low, &hi); | |
1525 | add_double (int1l, int1h, low, hi, &low, &hi); | |
d4b60170 | 1526 | overflow = OVERFLOW_SUM_SIGN (hi, int2h, int1h); |
e9a25f70 | 1527 | break; |
6d716ca8 | 1528 | |
e9a25f70 JL |
1529 | case MULT_EXPR: |
1530 | overflow = mul_double (int1l, int1h, int2l, int2h, &low, &hi); | |
1531 | break; | |
6d716ca8 | 1532 | |
e9a25f70 JL |
1533 | case TRUNC_DIV_EXPR: |
1534 | case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR: | |
1535 | case EXACT_DIV_EXPR: | |
1536 | /* This is a shortcut for a common special case. */ | |
05bccae2 | 1537 | if (int2h == 0 && (HOST_WIDE_INT) int2l > 0 |
e9a25f70 JL |
1538 | && ! TREE_CONSTANT_OVERFLOW (arg1) |
1539 | && ! TREE_CONSTANT_OVERFLOW (arg2) | |
05bccae2 | 1540 | && int1h == 0 && (HOST_WIDE_INT) int1l >= 0) |
e9a25f70 JL |
1541 | { |
1542 | if (code == CEIL_DIV_EXPR) | |
1543 | int1l += int2l - 1; | |
05bccae2 | 1544 | |
e9a25f70 | 1545 | low = int1l / int2l, hi = 0; |
6d716ca8 | 1546 | break; |
e9a25f70 | 1547 | } |
6d716ca8 | 1548 | |
e9a25f70 | 1549 | /* ... fall through ... */ |
6d716ca8 | 1550 | |
b6cc0a72 | 1551 | case ROUND_DIV_EXPR: |
e9a25f70 JL |
1552 | if (int2h == 0 && int2l == 1) |
1553 | { | |
1554 | low = int1l, hi = int1h; | |
6d716ca8 | 1555 | break; |
e9a25f70 JL |
1556 | } |
1557 | if (int1l == int2l && int1h == int2h | |
1558 | && ! (int1l == 0 && int1h == 0)) | |
1559 | { | |
1560 | low = 1, hi = 0; | |
63e7fe9b | 1561 | break; |
e9a25f70 JL |
1562 | } |
1563 | overflow = div_and_round_double (code, uns, | |
1564 | int1l, int1h, int2l, int2h, | |
1565 | &low, &hi, &garbagel, &garbageh); | |
1566 | break; | |
63e7fe9b | 1567 | |
e9a25f70 JL |
1568 | case TRUNC_MOD_EXPR: |
1569 | case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR: | |
1570 | /* This is a shortcut for a common special case. */ | |
05bccae2 | 1571 | if (int2h == 0 && (HOST_WIDE_INT) int2l > 0 |
e9a25f70 JL |
1572 | && ! TREE_CONSTANT_OVERFLOW (arg1) |
1573 | && ! TREE_CONSTANT_OVERFLOW (arg2) | |
05bccae2 | 1574 | && int1h == 0 && (HOST_WIDE_INT) int1l >= 0) |
e9a25f70 JL |
1575 | { |
1576 | if (code == CEIL_MOD_EXPR) | |
1577 | int1l += int2l - 1; | |
1578 | low = int1l % int2l, hi = 0; | |
63e7fe9b | 1579 | break; |
e9a25f70 | 1580 | } |
63e7fe9b | 1581 | |
e9a25f70 JL |
1582 | /* ... fall through ... */ |
1583 | ||
b6cc0a72 | 1584 | case ROUND_MOD_EXPR: |
e9a25f70 JL |
1585 | overflow = div_and_round_double (code, uns, |
1586 | int1l, int1h, int2l, int2h, | |
1587 | &garbagel, &garbageh, &low, &hi); | |
1588 | break; | |
1589 | ||
1590 | case MIN_EXPR: | |
1591 | case MAX_EXPR: | |
1592 | if (uns) | |
d4b60170 RK |
1593 | low = (((unsigned HOST_WIDE_INT) int1h |
1594 | < (unsigned HOST_WIDE_INT) int2h) | |
1595 | || (((unsigned HOST_WIDE_INT) int1h | |
1596 | == (unsigned HOST_WIDE_INT) int2h) | |
05bccae2 | 1597 | && int1l < int2l)); |
380ff34a | 1598 | else |
05bccae2 RK |
1599 | low = (int1h < int2h |
1600 | || (int1h == int2h && int1l < int2l)); | |
d4b60170 | 1601 | |
e9a25f70 JL |
1602 | if (low == (code == MIN_EXPR)) |
1603 | low = int1l, hi = int1h; | |
1604 | else | |
1605 | low = int2l, hi = int2h; | |
1606 | break; | |
3dedc65a | 1607 | |
e9a25f70 JL |
1608 | default: |
1609 | abort (); | |
3dedc65a | 1610 | } |
e9a25f70 | 1611 | |
44475138 RK |
1612 | if (forsize && hi == 0 && low < 10000 |
1613 | && overflow == 0 && ! TREE_OVERFLOW (arg1) && ! TREE_OVERFLOW (arg2)) | |
fed3cef0 | 1614 | return size_int_type_wide (low, TREE_TYPE (arg1)); |
e9a25f70 JL |
1615 | else |
1616 | { | |
1617 | t = build_int_2 (low, hi); | |
1618 | TREE_TYPE (t) = TREE_TYPE (arg1); | |
1619 | } | |
1620 | ||
1621 | TREE_OVERFLOW (t) | |
1622 | = ((notrunc ? (!uns || forsize) && overflow | |
1623 | : force_fit_type (t, (!uns || forsize) && overflow) && ! no_overflow) | |
1624 | | TREE_OVERFLOW (arg1) | |
1625 | | TREE_OVERFLOW (arg2)); | |
d4b60170 | 1626 | |
e9a25f70 JL |
1627 | /* If we're doing a size calculation, unsigned arithmetic does overflow. |
1628 | So check if force_fit_type truncated the value. */ | |
1629 | if (forsize | |
1630 | && ! TREE_OVERFLOW (t) | |
1631 | && (TREE_INT_CST_HIGH (t) != hi | |
1632 | || TREE_INT_CST_LOW (t) != low)) | |
1633 | TREE_OVERFLOW (t) = 1; | |
d4b60170 | 1634 | |
e9a25f70 JL |
1635 | TREE_CONSTANT_OVERFLOW (t) = (TREE_OVERFLOW (t) |
1636 | | TREE_CONSTANT_OVERFLOW (arg1) | |
1637 | | TREE_CONSTANT_OVERFLOW (arg2)); | |
1638 | return t; | |
1639 | } | |
1640 | ||
d4b60170 | 1641 | /* Define input and output argument for const_binop_1. */ |
a4d3481d KG |
1642 | struct cb_args |
1643 | { | |
b6cc0a72 KH |
1644 | enum tree_code code; /* Input: tree code for operation. */ |
1645 | tree type; /* Input: tree type for operation. */ | |
1646 | REAL_VALUE_TYPE d1, d2; /* Input: floating point operands. */ | |
1647 | tree t; /* Output: constant for result. */ | |
a4d3481d KG |
1648 | }; |
1649 | ||
d4b60170 RK |
1650 | /* Do the real arithmetic for const_binop while protected by a |
1651 | float overflow handler. */ | |
1652 | ||
a4d3481d KG |
1653 | static void |
1654 | const_binop_1 (data) | |
b6cc0a72 | 1655 | PTR data; |
a4d3481d | 1656 | { |
d4b60170 | 1657 | struct cb_args *args = (struct cb_args *) data; |
a4d3481d KG |
1658 | REAL_VALUE_TYPE value; |
1659 | ||
1660 | #ifdef REAL_ARITHMETIC | |
1661 | REAL_ARITHMETIC (value, args->code, args->d1, args->d2); | |
1662 | #else | |
1663 | switch (args->code) | |
1664 | { | |
1665 | case PLUS_EXPR: | |
1666 | value = args->d1 + args->d2; | |
1667 | break; | |
b6cc0a72 | 1668 | |
a4d3481d KG |
1669 | case MINUS_EXPR: |
1670 | value = args->d1 - args->d2; | |
1671 | break; | |
b6cc0a72 | 1672 | |
a4d3481d KG |
1673 | case MULT_EXPR: |
1674 | value = args->d1 * args->d2; | |
1675 | break; | |
b6cc0a72 | 1676 | |
a4d3481d KG |
1677 | case RDIV_EXPR: |
1678 | #ifndef REAL_INFINITY | |
1679 | if (args->d2 == 0) | |
1680 | abort (); | |
1681 | #endif | |
b6cc0a72 | 1682 | |
a4d3481d KG |
1683 | value = args->d1 / args->d2; |
1684 | break; | |
b6cc0a72 | 1685 | |
a4d3481d KG |
1686 | case MIN_EXPR: |
1687 | value = MIN (args->d1, args->d2); | |
1688 | break; | |
b6cc0a72 | 1689 | |
a4d3481d KG |
1690 | case MAX_EXPR: |
1691 | value = MAX (args->d1, args->d2); | |
1692 | break; | |
b6cc0a72 | 1693 | |
a4d3481d KG |
1694 | default: |
1695 | abort (); | |
1696 | } | |
1697 | #endif /* no REAL_ARITHMETIC */ | |
d4b60170 RK |
1698 | |
1699 | args->t | |
1700 | = build_real (args->type, | |
1701 | real_value_truncate (TYPE_MODE (args->type), value)); | |
a4d3481d KG |
1702 | } |
1703 | ||
d4b60170 RK |
1704 | /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new |
1705 | constant. We assume ARG1 and ARG2 have the same data type, or at least | |
1706 | are the same kind of constant and the same machine mode. | |
e9a25f70 JL |
1707 | |
1708 | If NOTRUNC is nonzero, do not truncate the result to fit the data type. */ | |
1709 | ||
1710 | static tree | |
1711 | const_binop (code, arg1, arg2, notrunc) | |
1712 | enum tree_code code; | |
1713 | register tree arg1, arg2; | |
1714 | int notrunc; | |
1715 | { | |
b6cc0a72 KH |
1716 | STRIP_NOPS (arg1); |
1717 | STRIP_NOPS (arg2); | |
e9a25f70 JL |
1718 | |
1719 | if (TREE_CODE (arg1) == INTEGER_CST) | |
1720 | return int_const_binop (code, arg1, arg2, notrunc, 0); | |
1721 | ||
6d716ca8 RS |
1722 | #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) |
1723 | if (TREE_CODE (arg1) == REAL_CST) | |
1724 | { | |
79c844cd RK |
1725 | REAL_VALUE_TYPE d1; |
1726 | REAL_VALUE_TYPE d2; | |
649ff3b4 | 1727 | int overflow = 0; |
7c7b029d | 1728 | tree t; |
a4d3481d | 1729 | struct cb_args args; |
6d716ca8 | 1730 | |
79c844cd RK |
1731 | d1 = TREE_REAL_CST (arg1); |
1732 | d2 = TREE_REAL_CST (arg2); | |
5f610074 RK |
1733 | |
1734 | /* If either operand is a NaN, just return it. Otherwise, set up | |
1735 | for floating-point trap; we return an overflow. */ | |
1736 | if (REAL_VALUE_ISNAN (d1)) | |
1737 | return arg1; | |
1738 | else if (REAL_VALUE_ISNAN (d2)) | |
1739 | return arg2; | |
a4d3481d KG |
1740 | |
1741 | /* Setup input for const_binop_1() */ | |
d4b60170 | 1742 | args.type = TREE_TYPE (arg1); |
a4d3481d KG |
1743 | args.d1 = d1; |
1744 | args.d2 = d2; | |
1745 | args.code = code; | |
b6cc0a72 | 1746 | |
a4d3481d | 1747 | if (do_float_handler (const_binop_1, (PTR) &args)) |
d4b60170 RK |
1748 | /* Receive output from const_binop_1. */ |
1749 | t = args.t; | |
a4d3481d | 1750 | else |
6d716ca8 | 1751 | { |
d4b60170 | 1752 | /* We got an exception from const_binop_1. */ |
a4d3481d KG |
1753 | t = copy_node (arg1); |
1754 | overflow = 1; | |
6d716ca8 | 1755 | } |
649ff3b4 RK |
1756 | |
1757 | TREE_OVERFLOW (t) | |
1758 | = (force_fit_type (t, overflow) | |
1759 | | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2)); | |
1760 | TREE_CONSTANT_OVERFLOW (t) | |
1761 | = TREE_OVERFLOW (t) | |
1762 | | TREE_CONSTANT_OVERFLOW (arg1) | |
1763 | | TREE_CONSTANT_OVERFLOW (arg2); | |
7c7b029d | 1764 | return t; |
6d716ca8 RS |
1765 | } |
1766 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
1767 | if (TREE_CODE (arg1) == COMPLEX_CST) | |
1768 | { | |
214d5b84 | 1769 | register tree type = TREE_TYPE (arg1); |
6d716ca8 RS |
1770 | register tree r1 = TREE_REALPART (arg1); |
1771 | register tree i1 = TREE_IMAGPART (arg1); | |
1772 | register tree r2 = TREE_REALPART (arg2); | |
1773 | register tree i2 = TREE_IMAGPART (arg2); | |
1774 | register tree t; | |
1775 | ||
1776 | switch (code) | |
1777 | { | |
1778 | case PLUS_EXPR: | |
214d5b84 RK |
1779 | t = build_complex (type, |
1780 | const_binop (PLUS_EXPR, r1, r2, notrunc), | |
91d33e36 | 1781 | const_binop (PLUS_EXPR, i1, i2, notrunc)); |
6d716ca8 RS |
1782 | break; |
1783 | ||
1784 | case MINUS_EXPR: | |
214d5b84 RK |
1785 | t = build_complex (type, |
1786 | const_binop (MINUS_EXPR, r1, r2, notrunc), | |
91d33e36 | 1787 | const_binop (MINUS_EXPR, i1, i2, notrunc)); |
6d716ca8 RS |
1788 | break; |
1789 | ||
1790 | case MULT_EXPR: | |
214d5b84 RK |
1791 | t = build_complex (type, |
1792 | const_binop (MINUS_EXPR, | |
91d33e36 RS |
1793 | const_binop (MULT_EXPR, |
1794 | r1, r2, notrunc), | |
1795 | const_binop (MULT_EXPR, | |
1796 | i1, i2, notrunc), | |
1797 | notrunc), | |
6d716ca8 | 1798 | const_binop (PLUS_EXPR, |
91d33e36 RS |
1799 | const_binop (MULT_EXPR, |
1800 | r1, i2, notrunc), | |
1801 | const_binop (MULT_EXPR, | |
1802 | i1, r2, notrunc), | |
1803 | notrunc)); | |
6d716ca8 RS |
1804 | break; |
1805 | ||
1806 | case RDIV_EXPR: | |
1807 | { | |
1808 | register tree magsquared | |
1809 | = const_binop (PLUS_EXPR, | |
91d33e36 RS |
1810 | const_binop (MULT_EXPR, r2, r2, notrunc), |
1811 | const_binop (MULT_EXPR, i2, i2, notrunc), | |
1812 | notrunc); | |
58633be8 | 1813 | |
214d5b84 RK |
1814 | t = build_complex (type, |
1815 | const_binop | |
1816 | (INTEGRAL_TYPE_P (TREE_TYPE (r1)) | |
1817 | ? TRUNC_DIV_EXPR : RDIV_EXPR, | |
1818 | const_binop (PLUS_EXPR, | |
1819 | const_binop (MULT_EXPR, r1, r2, | |
1820 | notrunc), | |
1821 | const_binop (MULT_EXPR, i1, i2, | |
1822 | notrunc), | |
1823 | notrunc), | |
1824 | magsquared, notrunc), | |
1825 | const_binop | |
1826 | (INTEGRAL_TYPE_P (TREE_TYPE (r1)) | |
1827 | ? TRUNC_DIV_EXPR : RDIV_EXPR, | |
1828 | const_binop (MINUS_EXPR, | |
1829 | const_binop (MULT_EXPR, i1, r2, | |
1830 | notrunc), | |
1831 | const_binop (MULT_EXPR, r1, i2, | |
1832 | notrunc), | |
1833 | notrunc), | |
1834 | magsquared, notrunc)); | |
6d716ca8 RS |
1835 | } |
1836 | break; | |
1837 | ||
1838 | default: | |
1839 | abort (); | |
1840 | } | |
6d716ca8 RS |
1841 | return t; |
1842 | } | |
1843 | return 0; | |
1844 | } | |
1845 | \f | |
06ceef4e | 1846 | /* Return an INTEGER_CST with value whose low-order HOST_BITS_PER_WIDE_INT |
fed3cef0 | 1847 | bits are given by NUMBER and of the sizetype represented by KIND. */ |
d4b60170 | 1848 | |
fed3cef0 RK |
1849 | tree |
1850 | size_int_wide (number, kind) | |
1851 | HOST_WIDE_INT number; | |
1852 | enum size_type_kind kind; | |
1853 | { | |
1854 | return size_int_type_wide (number, sizetype_tab[(int) kind]); | |
1855 | } | |
1856 | ||
1857 | /* Likewise, but the desired type is specified explicitly. */ | |
6d716ca8 RS |
1858 | |
1859 | tree | |
fed3cef0 | 1860 | size_int_type_wide (number, type) |
06ceef4e | 1861 | HOST_WIDE_INT number; |
fed3cef0 | 1862 | tree type; |
6d716ca8 | 1863 | { |
d4b60170 | 1864 | /* Type-size nodes already made for small sizes. */ |
770ae6cc | 1865 | static tree size_table[2048 + 1]; |
d4b60170 | 1866 | static int init_p = 0; |
a3770a81 | 1867 | tree t; |
b6cc0a72 | 1868 | |
1f8f4a0b | 1869 | if (! init_p) |
6d716ca8 | 1870 | { |
d4b60170 RK |
1871 | ggc_add_tree_root ((tree *) size_table, |
1872 | sizeof size_table / sizeof (tree)); | |
1873 | init_p = 1; | |
1874 | } | |
1875 | ||
06ceef4e RK |
1876 | /* If this is a positive number that fits in the table we use to hold |
1877 | cached entries, see if it is already in the table and put it there | |
1878 | if not. */ | |
b6a1cbae | 1879 | if (number >= 0 && number < (int) ARRAY_SIZE (size_table)) |
d4b60170 | 1880 | { |
fed3cef0 RK |
1881 | if (size_table[number] != 0) |
1882 | for (t = size_table[number]; t != 0; t = TREE_CHAIN (t)) | |
1883 | if (TREE_TYPE (t) == type) | |
1884 | return t; | |
06ceef4e | 1885 | |
d4b60170 | 1886 | t = build_int_2 (number, 0); |
fed3cef0 RK |
1887 | TREE_TYPE (t) = type; |
1888 | TREE_CHAIN (t) = size_table[number]; | |
1889 | size_table[number] = t; | |
d4b60170 | 1890 | |
d4b60170 | 1891 | return t; |
6d716ca8 | 1892 | } |
a3770a81 | 1893 | |
fed3cef0 RK |
1894 | t = build_int_2 (number, number < 0 ? -1 : 0); |
1895 | TREE_TYPE (t) = type; | |
a3770a81 | 1896 | TREE_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (t) = force_fit_type (t, 0); |
6d716ca8 RS |
1897 | return t; |
1898 | } | |
1899 | ||
fed3cef0 RK |
1900 | /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE |
1901 | is a tree code. The type of the result is taken from the operands. | |
1902 | Both must be the same type integer type and it must be a size type. | |
6d716ca8 RS |
1903 | If the operands are constant, so is the result. */ |
1904 | ||
1905 | tree | |
1906 | size_binop (code, arg0, arg1) | |
1907 | enum tree_code code; | |
1908 | tree arg0, arg1; | |
1909 | { | |
fed3cef0 RK |
1910 | tree type = TREE_TYPE (arg0); |
1911 | ||
21318741 RK |
1912 | if (TREE_CODE (type) != INTEGER_TYPE || ! TYPE_IS_SIZETYPE (type) |
1913 | || type != TREE_TYPE (arg1)) | |
fed3cef0 RK |
1914 | abort (); |
1915 | ||
6d716ca8 RS |
1916 | /* Handle the special case of two integer constants faster. */ |
1917 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) | |
1918 | { | |
1919 | /* And some specific cases even faster than that. */ | |
9898deac | 1920 | if (code == PLUS_EXPR && integer_zerop (arg0)) |
6d716ca8 | 1921 | return arg1; |
9898deac RK |
1922 | else if ((code == MINUS_EXPR || code == PLUS_EXPR) |
1923 | && integer_zerop (arg1)) | |
6d716ca8 | 1924 | return arg0; |
9898deac | 1925 | else if (code == MULT_EXPR && integer_onep (arg0)) |
6d716ca8 | 1926 | return arg1; |
9898deac | 1927 | |
6d716ca8 | 1928 | /* Handle general case of two integer constants. */ |
e9a25f70 | 1929 | return int_const_binop (code, arg0, arg1, 0, 1); |
6d716ca8 RS |
1930 | } |
1931 | ||
1932 | if (arg0 == error_mark_node || arg1 == error_mark_node) | |
1933 | return error_mark_node; | |
1934 | ||
fed3cef0 | 1935 | return fold (build (code, type, arg0, arg1)); |
6d716ca8 | 1936 | } |
697073d9 | 1937 | |
fed3cef0 RK |
1938 | /* Given two values, either both of sizetype or both of bitsizetype, |
1939 | compute the difference between the two values. Return the value | |
1940 | in signed type corresponding to the type of the operands. */ | |
697073d9 JM |
1941 | |
1942 | tree | |
fed3cef0 | 1943 | size_diffop (arg0, arg1) |
697073d9 JM |
1944 | tree arg0, arg1; |
1945 | { | |
fed3cef0 RK |
1946 | tree type = TREE_TYPE (arg0); |
1947 | tree ctype; | |
697073d9 | 1948 | |
21318741 RK |
1949 | if (TREE_CODE (type) != INTEGER_TYPE || ! TYPE_IS_SIZETYPE (type) |
1950 | || type != TREE_TYPE (arg1)) | |
fed3cef0 | 1951 | abort (); |
697073d9 | 1952 | |
fed3cef0 RK |
1953 | /* If the type is already signed, just do the simple thing. */ |
1954 | if (! TREE_UNSIGNED (type)) | |
1955 | return size_binop (MINUS_EXPR, arg0, arg1); | |
1956 | ||
1957 | ctype = (type == bitsizetype || type == ubitsizetype | |
1958 | ? sbitsizetype : ssizetype); | |
1959 | ||
1960 | /* If either operand is not a constant, do the conversions to the signed | |
1961 | type and subtract. The hardware will do the right thing with any | |
1962 | overflow in the subtraction. */ | |
1963 | if (TREE_CODE (arg0) != INTEGER_CST || TREE_CODE (arg1) != INTEGER_CST) | |
1964 | return size_binop (MINUS_EXPR, convert (ctype, arg0), | |
1965 | convert (ctype, arg1)); | |
1966 | ||
1967 | /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE. | |
1968 | Otherwise, subtract the other way, convert to CTYPE (we know that can't | |
1969 | overflow) and negate (which can't either). Special-case a result | |
1970 | of zero while we're here. */ | |
1971 | if (tree_int_cst_equal (arg0, arg1)) | |
1972 | return convert (ctype, integer_zero_node); | |
1973 | else if (tree_int_cst_lt (arg1, arg0)) | |
1974 | return convert (ctype, size_binop (MINUS_EXPR, arg0, arg1)); | |
1975 | else | |
1976 | return size_binop (MINUS_EXPR, convert (ctype, integer_zero_node), | |
1977 | convert (ctype, size_binop (MINUS_EXPR, arg1, arg0))); | |
697073d9 | 1978 | } |
6d716ca8 | 1979 | \f |
d4b60170 | 1980 | /* This structure is used to communicate arguments to fold_convert_1. */ |
a4d3481d KG |
1981 | struct fc_args |
1982 | { | |
d4b60170 RK |
1983 | tree arg1; /* Input: value to convert. */ |
1984 | tree type; /* Input: type to convert value to. */ | |
1985 | tree t; /* Ouput: result of conversion. */ | |
a4d3481d KG |
1986 | }; |
1987 | ||
d4b60170 RK |
1988 | /* Function to convert floating-point constants, protected by floating |
1989 | point exception handler. */ | |
1990 | ||
a4d3481d KG |
1991 | static void |
1992 | fold_convert_1 (data) | |
b6cc0a72 | 1993 | PTR data; |
a4d3481d | 1994 | { |
b6cc0a72 | 1995 | struct fc_args *args = (struct fc_args *) data; |
a4d3481d KG |
1996 | |
1997 | args->t = build_real (args->type, | |
1998 | real_value_truncate (TYPE_MODE (args->type), | |
1999 | TREE_REAL_CST (args->arg1))); | |
2000 | } | |
2001 | ||
6d716ca8 RS |
2002 | /* Given T, a tree representing type conversion of ARG1, a constant, |
2003 | return a constant tree representing the result of conversion. */ | |
2004 | ||
2005 | static tree | |
2006 | fold_convert (t, arg1) | |
2007 | register tree t; | |
2008 | register tree arg1; | |
2009 | { | |
2010 | register tree type = TREE_TYPE (t); | |
649ff3b4 | 2011 | int overflow = 0; |
6d716ca8 | 2012 | |
e5e809f4 | 2013 | if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)) |
6d716ca8 RS |
2014 | { |
2015 | if (TREE_CODE (arg1) == INTEGER_CST) | |
2016 | { | |
e3374525 RK |
2017 | /* If we would build a constant wider than GCC supports, |
2018 | leave the conversion unfolded. */ | |
2019 | if (TYPE_PRECISION (type) > 2 * HOST_BITS_PER_WIDE_INT) | |
2020 | return t; | |
2021 | ||
fed3cef0 RK |
2022 | /* If we are trying to make a sizetype for a small integer, use |
2023 | size_int to pick up cached types to reduce duplicate nodes. */ | |
55560b9d | 2024 | if (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type) |
ac50176d | 2025 | && !TREE_CONSTANT_OVERFLOW (arg1) |
770ae6cc | 2026 | && compare_tree_int (arg1, 10000) < 0) |
fed3cef0 RK |
2027 | return size_int_type_wide (TREE_INT_CST_LOW (arg1), type); |
2028 | ||
6d716ca8 RS |
2029 | /* Given an integer constant, make new constant with new type, |
2030 | appropriately sign-extended or truncated. */ | |
2031 | t = build_int_2 (TREE_INT_CST_LOW (arg1), | |
2032 | TREE_INT_CST_HIGH (arg1)); | |
2033 | TREE_TYPE (t) = type; | |
e0f776fb | 2034 | /* Indicate an overflow if (1) ARG1 already overflowed, |
dc3907c5 PE |
2035 | or (2) force_fit_type indicates an overflow. |
2036 | Tell force_fit_type that an overflow has already occurred | |
b472527b JL |
2037 | if ARG1 is a too-large unsigned value and T is signed. |
2038 | But don't indicate an overflow if converting a pointer. */ | |
dc3907c5 | 2039 | TREE_OVERFLOW (t) |
e5e809f4 JL |
2040 | = ((force_fit_type (t, |
2041 | (TREE_INT_CST_HIGH (arg1) < 0 | |
4f242db3 | 2042 | && (TREE_UNSIGNED (type) |
e5e809f4 JL |
2043 | < TREE_UNSIGNED (TREE_TYPE (arg1))))) |
2044 | && ! POINTER_TYPE_P (TREE_TYPE (arg1))) | |
2045 | || TREE_OVERFLOW (arg1)); | |
dc3907c5 PE |
2046 | TREE_CONSTANT_OVERFLOW (t) |
2047 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
6d716ca8 RS |
2048 | } |
2049 | #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) | |
2050 | else if (TREE_CODE (arg1) == REAL_CST) | |
2051 | { | |
4b8a0062 RK |
2052 | /* Don't initialize these, use assignments. |
2053 | Initialized local aggregates don't work on old compilers. */ | |
2054 | REAL_VALUE_TYPE x; | |
2055 | REAL_VALUE_TYPE l; | |
2056 | REAL_VALUE_TYPE u; | |
7cb6a121 | 2057 | tree type1 = TREE_TYPE (arg1); |
e1ee5cdc | 2058 | int no_upper_bound; |
4b8a0062 RK |
2059 | |
2060 | x = TREE_REAL_CST (arg1); | |
7cb6a121 | 2061 | l = real_value_from_int_cst (type1, TYPE_MIN_VALUE (type)); |
e1ee5cdc RH |
2062 | |
2063 | no_upper_bound = (TYPE_MAX_VALUE (type) == NULL); | |
2064 | if (!no_upper_bound) | |
2065 | u = real_value_from_int_cst (type1, TYPE_MAX_VALUE (type)); | |
2066 | ||
4b3d5ea0 RS |
2067 | /* See if X will be in range after truncation towards 0. |
2068 | To compensate for truncation, move the bounds away from 0, | |
2069 | but reject if X exactly equals the adjusted bounds. */ | |
2070 | #ifdef REAL_ARITHMETIC | |
2071 | REAL_ARITHMETIC (l, MINUS_EXPR, l, dconst1); | |
e1ee5cdc RH |
2072 | if (!no_upper_bound) |
2073 | REAL_ARITHMETIC (u, PLUS_EXPR, u, dconst1); | |
4b3d5ea0 RS |
2074 | #else |
2075 | l--; | |
e1ee5cdc RH |
2076 | if (!no_upper_bound) |
2077 | u++; | |
4b3d5ea0 | 2078 | #endif |
5f610074 RK |
2079 | /* If X is a NaN, use zero instead and show we have an overflow. |
2080 | Otherwise, range check. */ | |
2081 | if (REAL_VALUE_ISNAN (x)) | |
2082 | overflow = 1, x = dconst0; | |
e1ee5cdc RH |
2083 | else if (! (REAL_VALUES_LESS (l, x) |
2084 | && !no_upper_bound | |
2085 | && REAL_VALUES_LESS (x, u))) | |
649ff3b4 RK |
2086 | overflow = 1; |
2087 | ||
6d716ca8 RS |
2088 | #ifndef REAL_ARITHMETIC |
2089 | { | |
906c4e36 RK |
2090 | HOST_WIDE_INT low, high; |
2091 | HOST_WIDE_INT half_word | |
2092 | = (HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2); | |
6d716ca8 | 2093 | |
5f610074 RK |
2094 | if (x < 0) |
2095 | x = -x; | |
6d716ca8 | 2096 | |
5f610074 RK |
2097 | high = (HOST_WIDE_INT) (x / half_word / half_word); |
2098 | x -= (REAL_VALUE_TYPE) high * half_word * half_word; | |
2099 | if (x >= (REAL_VALUE_TYPE) half_word * half_word / 2) | |
b6b19f41 | 2100 | { |
5f610074 | 2101 | low = x - (REAL_VALUE_TYPE) half_word * half_word / 2; |
e0f776fb | 2102 | low |= (HOST_WIDE_INT) -1 << (HOST_BITS_PER_WIDE_INT - 1); |
b6b19f41 RS |
2103 | } |
2104 | else | |
5f610074 | 2105 | low = (HOST_WIDE_INT) x; |
6d716ca8 RS |
2106 | if (TREE_REAL_CST (arg1) < 0) |
2107 | neg_double (low, high, &low, &high); | |
2108 | t = build_int_2 (low, high); | |
2109 | } | |
2110 | #else | |
2111 | { | |
906c4e36 | 2112 | HOST_WIDE_INT low, high; |
5f610074 | 2113 | REAL_VALUE_TO_INT (&low, &high, x); |
6d716ca8 RS |
2114 | t = build_int_2 (low, high); |
2115 | } | |
2116 | #endif | |
2117 | TREE_TYPE (t) = type; | |
649ff3b4 RK |
2118 | TREE_OVERFLOW (t) |
2119 | = TREE_OVERFLOW (arg1) | force_fit_type (t, overflow); | |
2120 | TREE_CONSTANT_OVERFLOW (t) | |
2121 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
6d716ca8 RS |
2122 | } |
2123 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
2124 | TREE_TYPE (t) = type; | |
2125 | } | |
2126 | else if (TREE_CODE (type) == REAL_TYPE) | |
2127 | { | |
2128 | #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) | |
2129 | if (TREE_CODE (arg1) == INTEGER_CST) | |
2130 | return build_real_from_int_cst (type, arg1); | |
2131 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
2132 | if (TREE_CODE (arg1) == REAL_CST) | |
7c7b029d | 2133 | { |
a4d3481d | 2134 | struct fc_args args; |
b6cc0a72 | 2135 | |
5f610074 | 2136 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))) |
a377ff85 RK |
2137 | { |
2138 | t = arg1; | |
2139 | TREE_TYPE (arg1) = type; | |
2140 | return t; | |
2141 | } | |
a4d3481d KG |
2142 | |
2143 | /* Setup input for fold_convert_1() */ | |
2144 | args.arg1 = arg1; | |
2145 | args.type = type; | |
b6cc0a72 | 2146 | |
a4d3481d KG |
2147 | if (do_float_handler (fold_convert_1, (PTR) &args)) |
2148 | { | |
2149 | /* Receive output from fold_convert_1() */ | |
2150 | t = args.t; | |
2151 | } | |
2152 | else | |
7c7b029d | 2153 | { |
a4d3481d | 2154 | /* We got an exception from fold_convert_1() */ |
649ff3b4 RK |
2155 | overflow = 1; |
2156 | t = copy_node (arg1); | |
7c7b029d | 2157 | } |
649ff3b4 | 2158 | |
649ff3b4 RK |
2159 | TREE_OVERFLOW (t) |
2160 | = TREE_OVERFLOW (arg1) | force_fit_type (t, overflow); | |
2161 | TREE_CONSTANT_OVERFLOW (t) | |
2162 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
7c7b029d RS |
2163 | return t; |
2164 | } | |
6d716ca8 RS |
2165 | } |
2166 | TREE_CONSTANT (t) = 1; | |
2167 | return t; | |
2168 | } | |
2169 | \f | |
ff59bfe6 | 2170 | /* Return an expr equal to X but certainly not valid as an lvalue. */ |
6d716ca8 RS |
2171 | |
2172 | tree | |
2173 | non_lvalue (x) | |
2174 | tree x; | |
2175 | { | |
2176 | tree result; | |
2177 | ||
2178 | /* These things are certainly not lvalues. */ | |
2179 | if (TREE_CODE (x) == NON_LVALUE_EXPR | |
2180 | || TREE_CODE (x) == INTEGER_CST | |
2181 | || TREE_CODE (x) == REAL_CST | |
2182 | || TREE_CODE (x) == STRING_CST | |
2183 | || TREE_CODE (x) == ADDR_EXPR) | |
ff59bfe6 | 2184 | return x; |
6d716ca8 RS |
2185 | |
2186 | result = build1 (NON_LVALUE_EXPR, TREE_TYPE (x), x); | |
2187 | TREE_CONSTANT (result) = TREE_CONSTANT (x); | |
2188 | return result; | |
2189 | } | |
a5e9b124 | 2190 | |
e9866da3 JM |
2191 | /* Nonzero means lvalues are limited to those valid in pedantic ANSI C. |
2192 | Zero means allow extended lvalues. */ | |
2193 | ||
2194 | int pedantic_lvalues; | |
2195 | ||
a5e9b124 JW |
2196 | /* When pedantic, return an expr equal to X but certainly not valid as a |
2197 | pedantic lvalue. Otherwise, return X. */ | |
2198 | ||
2199 | tree | |
2200 | pedantic_non_lvalue (x) | |
2201 | tree x; | |
2202 | { | |
e9866da3 | 2203 | if (pedantic_lvalues) |
a5e9b124 JW |
2204 | return non_lvalue (x); |
2205 | else | |
2206 | return x; | |
2207 | } | |
c05a9b68 RS |
2208 | \f |
2209 | /* Given a tree comparison code, return the code that is the logical inverse | |
2210 | of the given code. It is not safe to do this for floating-point | |
2211 | comparisons, except for NE_EXPR and EQ_EXPR. */ | |
6d716ca8 | 2212 | |
c05a9b68 RS |
2213 | static enum tree_code |
2214 | invert_tree_comparison (code) | |
2215 | enum tree_code code; | |
2216 | { | |
2217 | switch (code) | |
2218 | { | |
2219 | case EQ_EXPR: | |
2220 | return NE_EXPR; | |
2221 | case NE_EXPR: | |
2222 | return EQ_EXPR; | |
2223 | case GT_EXPR: | |
2224 | return LE_EXPR; | |
2225 | case GE_EXPR: | |
2226 | return LT_EXPR; | |
2227 | case LT_EXPR: | |
2228 | return GE_EXPR; | |
2229 | case LE_EXPR: | |
2230 | return GT_EXPR; | |
2231 | default: | |
2232 | abort (); | |
2233 | } | |
2234 | } | |
2235 | ||
2236 | /* Similar, but return the comparison that results if the operands are | |
2237 | swapped. This is safe for floating-point. */ | |
2238 | ||
2239 | static enum tree_code | |
2240 | swap_tree_comparison (code) | |
2241 | enum tree_code code; | |
2242 | { | |
2243 | switch (code) | |
2244 | { | |
2245 | case EQ_EXPR: | |
2246 | case NE_EXPR: | |
2247 | return code; | |
2248 | case GT_EXPR: | |
2249 | return LT_EXPR; | |
2250 | case GE_EXPR: | |
2251 | return LE_EXPR; | |
2252 | case LT_EXPR: | |
2253 | return GT_EXPR; | |
2254 | case LE_EXPR: | |
2255 | return GE_EXPR; | |
2256 | default: | |
2257 | abort (); | |
2258 | } | |
2259 | } | |
61f275ff RK |
2260 | |
2261 | /* Return nonzero if CODE is a tree code that represents a truth value. */ | |
2262 | ||
2263 | static int | |
2264 | truth_value_p (code) | |
2265 | enum tree_code code; | |
2266 | { | |
2267 | return (TREE_CODE_CLASS (code) == '<' | |
2268 | || code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR | |
2269 | || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR | |
2270 | || code == TRUTH_XOR_EXPR || code == TRUTH_NOT_EXPR); | |
2271 | } | |
c05a9b68 | 2272 | \f |
6a1746af RS |
2273 | /* Return nonzero if two operands are necessarily equal. |
2274 | If ONLY_CONST is non-zero, only return non-zero for constants. | |
2275 | This function tests whether the operands are indistinguishable; | |
2276 | it does not test whether they are equal using C's == operation. | |
2277 | The distinction is important for IEEE floating point, because | |
2278 | (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and | |
2279 | (2) two NaNs may be indistinguishable, but NaN!=NaN. */ | |
6d716ca8 RS |
2280 | |
2281 | int | |
2282 | operand_equal_p (arg0, arg1, only_const) | |
2283 | tree arg0, arg1; | |
2284 | int only_const; | |
2285 | { | |
2286 | /* If both types don't have the same signedness, then we can't consider | |
2287 | them equal. We must check this before the STRIP_NOPS calls | |
2288 | because they may change the signedness of the arguments. */ | |
2289 | if (TREE_UNSIGNED (TREE_TYPE (arg0)) != TREE_UNSIGNED (TREE_TYPE (arg1))) | |
2290 | return 0; | |
2291 | ||
2292 | STRIP_NOPS (arg0); | |
2293 | STRIP_NOPS (arg1); | |
2294 | ||
c7cfe938 RK |
2295 | if (TREE_CODE (arg0) != TREE_CODE (arg1) |
2296 | /* This is needed for conversions and for COMPONENT_REF. | |
2297 | Might as well play it safe and always test this. */ | |
e89a9554 ZW |
2298 | || TREE_CODE (TREE_TYPE (arg0)) == ERROR_MARK |
2299 | || TREE_CODE (TREE_TYPE (arg1)) == ERROR_MARK | |
c7cfe938 | 2300 | || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1))) |
6d716ca8 RS |
2301 | return 0; |
2302 | ||
c7cfe938 RK |
2303 | /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal. |
2304 | We don't care about side effects in that case because the SAVE_EXPR | |
2305 | takes care of that for us. In all other cases, two expressions are | |
2306 | equal if they have no side effects. If we have two identical | |
2307 | expressions with side effects that should be treated the same due | |
2308 | to the only side effects being identical SAVE_EXPR's, that will | |
2309 | be detected in the recursive calls below. */ | |
2310 | if (arg0 == arg1 && ! only_const | |
2311 | && (TREE_CODE (arg0) == SAVE_EXPR | |
2312 | || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1)))) | |
6d716ca8 RS |
2313 | return 1; |
2314 | ||
c7cfe938 RK |
2315 | /* Next handle constant cases, those for which we can return 1 even |
2316 | if ONLY_CONST is set. */ | |
2317 | if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1)) | |
2318 | switch (TREE_CODE (arg0)) | |
2319 | { | |
2320 | case INTEGER_CST: | |
3c9b0091 RK |
2321 | return (! TREE_CONSTANT_OVERFLOW (arg0) |
2322 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
05bccae2 | 2323 | && tree_int_cst_equal (arg0, arg1)); |
c7cfe938 RK |
2324 | |
2325 | case REAL_CST: | |
3c9b0091 RK |
2326 | return (! TREE_CONSTANT_OVERFLOW (arg0) |
2327 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
41c9120b PE |
2328 | && REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0), |
2329 | TREE_REAL_CST (arg1))); | |
c7cfe938 RK |
2330 | |
2331 | case COMPLEX_CST: | |
2332 | return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1), | |
2333 | only_const) | |
2334 | && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1), | |
2335 | only_const)); | |
2336 | ||
2337 | case STRING_CST: | |
2338 | return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1) | |
71145810 | 2339 | && ! memcmp (TREE_STRING_POINTER (arg0), |
c7cfe938 RK |
2340 | TREE_STRING_POINTER (arg1), |
2341 | TREE_STRING_LENGTH (arg0))); | |
2342 | ||
2343 | case ADDR_EXPR: | |
2344 | return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), | |
2345 | 0); | |
e9a25f70 JL |
2346 | default: |
2347 | break; | |
c7cfe938 | 2348 | } |
6d716ca8 RS |
2349 | |
2350 | if (only_const) | |
2351 | return 0; | |
2352 | ||
6d716ca8 RS |
2353 | switch (TREE_CODE_CLASS (TREE_CODE (arg0))) |
2354 | { | |
2355 | case '1': | |
2356 | /* Two conversions are equal only if signedness and modes match. */ | |
2357 | if ((TREE_CODE (arg0) == NOP_EXPR || TREE_CODE (arg0) == CONVERT_EXPR) | |
2358 | && (TREE_UNSIGNED (TREE_TYPE (arg0)) | |
2359 | != TREE_UNSIGNED (TREE_TYPE (arg1)))) | |
2360 | return 0; | |
2361 | ||
2362 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
2363 | TREE_OPERAND (arg1, 0), 0); | |
2364 | ||
2365 | case '<': | |
2366 | case '2': | |
c7cfe938 RK |
2367 | if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0) |
2368 | && operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), | |
2369 | 0)) | |
2370 | return 1; | |
2371 | ||
2372 | /* For commutative ops, allow the other order. */ | |
2373 | return ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MULT_EXPR | |
2374 | || TREE_CODE (arg0) == MIN_EXPR || TREE_CODE (arg0) == MAX_EXPR | |
2375 | || TREE_CODE (arg0) == BIT_IOR_EXPR | |
2376 | || TREE_CODE (arg0) == BIT_XOR_EXPR | |
2377 | || TREE_CODE (arg0) == BIT_AND_EXPR | |
2378 | || TREE_CODE (arg0) == NE_EXPR || TREE_CODE (arg0) == EQ_EXPR) | |
2379 | && operand_equal_p (TREE_OPERAND (arg0, 0), | |
2380 | TREE_OPERAND (arg1, 1), 0) | |
6d716ca8 | 2381 | && operand_equal_p (TREE_OPERAND (arg0, 1), |
c7cfe938 | 2382 | TREE_OPERAND (arg1, 0), 0)); |
6d716ca8 RS |
2383 | |
2384 | case 'r': | |
05ca5990 GRK |
2385 | /* If either of the pointer (or reference) expressions we are dereferencing |
2386 | contain a side effect, these cannot be equal. */ | |
2387 | if (TREE_SIDE_EFFECTS (arg0) | |
2388 | || TREE_SIDE_EFFECTS (arg1)) | |
2389 | return 0; | |
2390 | ||
6d716ca8 RS |
2391 | switch (TREE_CODE (arg0)) |
2392 | { | |
2393 | case INDIRECT_REF: | |
2394 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
2395 | TREE_OPERAND (arg1, 0), 0); | |
2396 | ||
2397 | case COMPONENT_REF: | |
2398 | case ARRAY_REF: | |
2399 | return (operand_equal_p (TREE_OPERAND (arg0, 0), | |
2400 | TREE_OPERAND (arg1, 0), 0) | |
2401 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
2402 | TREE_OPERAND (arg1, 1), 0)); | |
2403 | ||
2404 | case BIT_FIELD_REF: | |
2405 | return (operand_equal_p (TREE_OPERAND (arg0, 0), | |
2406 | TREE_OPERAND (arg1, 0), 0) | |
2407 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
2408 | TREE_OPERAND (arg1, 1), 0) | |
2409 | && operand_equal_p (TREE_OPERAND (arg0, 2), | |
2410 | TREE_OPERAND (arg1, 2), 0)); | |
e9a25f70 JL |
2411 | default: |
2412 | return 0; | |
6d716ca8 | 2413 | } |
45f97e2e RH |
2414 | |
2415 | case 'e': | |
2416 | if (TREE_CODE (arg0) == RTL_EXPR) | |
2417 | return rtx_equal_p (RTL_EXPR_RTL (arg0), RTL_EXPR_RTL (arg1)); | |
2418 | return 0; | |
b6cc0a72 | 2419 | |
e9a25f70 JL |
2420 | default: |
2421 | return 0; | |
6d716ca8 | 2422 | } |
6d716ca8 | 2423 | } |
c05a9b68 RS |
2424 | \f |
2425 | /* Similar to operand_equal_p, but see if ARG0 might have been made by | |
b6cc0a72 | 2426 | shorten_compare from ARG1 when ARG1 was being compared with OTHER. |
6d716ca8 | 2427 | |
6d716ca8 RS |
2428 | When in doubt, return 0. */ |
2429 | ||
b6cc0a72 | 2430 | static int |
c05a9b68 RS |
2431 | operand_equal_for_comparison_p (arg0, arg1, other) |
2432 | tree arg0, arg1; | |
2433 | tree other; | |
6d716ca8 | 2434 | { |
c05a9b68 | 2435 | int unsignedp1, unsignedpo; |
52de9b6c | 2436 | tree primarg0, primarg1, primother; |
770ae6cc | 2437 | unsigned int correct_width; |
6d716ca8 | 2438 | |
c05a9b68 | 2439 | if (operand_equal_p (arg0, arg1, 0)) |
6d716ca8 RS |
2440 | return 1; |
2441 | ||
0982a4b8 JM |
2442 | if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0)) |
2443 | || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1))) | |
6d716ca8 RS |
2444 | return 0; |
2445 | ||
52de9b6c RK |
2446 | /* Discard any conversions that don't change the modes of ARG0 and ARG1 |
2447 | and see if the inner values are the same. This removes any | |
2448 | signedness comparison, which doesn't matter here. */ | |
2449 | primarg0 = arg0, primarg1 = arg1; | |
b6cc0a72 KH |
2450 | STRIP_NOPS (primarg0); |
2451 | STRIP_NOPS (primarg1); | |
52de9b6c RK |
2452 | if (operand_equal_p (primarg0, primarg1, 0)) |
2453 | return 1; | |
2454 | ||
c05a9b68 RS |
2455 | /* Duplicate what shorten_compare does to ARG1 and see if that gives the |
2456 | actual comparison operand, ARG0. | |
6d716ca8 | 2457 | |
c05a9b68 | 2458 | First throw away any conversions to wider types |
6d716ca8 | 2459 | already present in the operands. */ |
6d716ca8 | 2460 | |
c05a9b68 RS |
2461 | primarg1 = get_narrower (arg1, &unsignedp1); |
2462 | primother = get_narrower (other, &unsignedpo); | |
2463 | ||
2464 | correct_width = TYPE_PRECISION (TREE_TYPE (arg1)); | |
2465 | if (unsignedp1 == unsignedpo | |
2466 | && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width | |
2467 | && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width) | |
6d716ca8 | 2468 | { |
c05a9b68 | 2469 | tree type = TREE_TYPE (arg0); |
6d716ca8 RS |
2470 | |
2471 | /* Make sure shorter operand is extended the right way | |
2472 | to match the longer operand. */ | |
c05a9b68 | 2473 | primarg1 = convert (signed_or_unsigned_type (unsignedp1, |
b6cc0a72 KH |
2474 | TREE_TYPE (primarg1)), |
2475 | primarg1); | |
6d716ca8 | 2476 | |
c05a9b68 | 2477 | if (operand_equal_p (arg0, convert (type, primarg1), 0)) |
6d716ca8 RS |
2478 | return 1; |
2479 | } | |
2480 | ||
2481 | return 0; | |
2482 | } | |
2483 | \f | |
f72aed24 | 2484 | /* See if ARG is an expression that is either a comparison or is performing |
c05a9b68 RS |
2485 | arithmetic on comparisons. The comparisons must only be comparing |
2486 | two different values, which will be stored in *CVAL1 and *CVAL2; if | |
2487 | they are non-zero it means that some operands have already been found. | |
2488 | No variables may be used anywhere else in the expression except in the | |
35e66bd1 RK |
2489 | comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around |
2490 | the expression and save_expr needs to be called with CVAL1 and CVAL2. | |
c05a9b68 RS |
2491 | |
2492 | If this is true, return 1. Otherwise, return zero. */ | |
2493 | ||
2494 | static int | |
35e66bd1 | 2495 | twoval_comparison_p (arg, cval1, cval2, save_p) |
c05a9b68 RS |
2496 | tree arg; |
2497 | tree *cval1, *cval2; | |
35e66bd1 | 2498 | int *save_p; |
c05a9b68 RS |
2499 | { |
2500 | enum tree_code code = TREE_CODE (arg); | |
2501 | char class = TREE_CODE_CLASS (code); | |
2502 | ||
2503 | /* We can handle some of the 'e' cases here. */ | |
35e66bd1 | 2504 | if (class == 'e' && code == TRUTH_NOT_EXPR) |
c05a9b68 RS |
2505 | class = '1'; |
2506 | else if (class == 'e' | |
2507 | && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR | |
2508 | || code == COMPOUND_EXPR)) | |
2509 | class = '2'; | |
2315a5db | 2510 | |
d4b60170 RK |
2511 | else if (class == 'e' && code == SAVE_EXPR && SAVE_EXPR_RTL (arg) == 0 |
2512 | && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0))) | |
35e66bd1 RK |
2513 | { |
2514 | /* If we've already found a CVAL1 or CVAL2, this expression is | |
2515 | two complex to handle. */ | |
2516 | if (*cval1 || *cval2) | |
2517 | return 0; | |
2518 | ||
2519 | class = '1'; | |
2520 | *save_p = 1; | |
2521 | } | |
c05a9b68 RS |
2522 | |
2523 | switch (class) | |
2524 | { | |
2525 | case '1': | |
35e66bd1 | 2526 | return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p); |
c05a9b68 RS |
2527 | |
2528 | case '2': | |
35e66bd1 RK |
2529 | return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p) |
2530 | && twoval_comparison_p (TREE_OPERAND (arg, 1), | |
2531 | cval1, cval2, save_p)); | |
c05a9b68 RS |
2532 | |
2533 | case 'c': | |
2534 | return 1; | |
2535 | ||
2536 | case 'e': | |
2537 | if (code == COND_EXPR) | |
35e66bd1 RK |
2538 | return (twoval_comparison_p (TREE_OPERAND (arg, 0), |
2539 | cval1, cval2, save_p) | |
2540 | && twoval_comparison_p (TREE_OPERAND (arg, 1), | |
2541 | cval1, cval2, save_p) | |
c05a9b68 | 2542 | && twoval_comparison_p (TREE_OPERAND (arg, 2), |
35e66bd1 | 2543 | cval1, cval2, save_p)); |
c05a9b68 | 2544 | return 0; |
b6cc0a72 | 2545 | |
c05a9b68 RS |
2546 | case '<': |
2547 | /* First see if we can handle the first operand, then the second. For | |
2548 | the second operand, we know *CVAL1 can't be zero. It must be that | |
2549 | one side of the comparison is each of the values; test for the | |
2550 | case where this isn't true by failing if the two operands | |
2551 | are the same. */ | |
2552 | ||
2553 | if (operand_equal_p (TREE_OPERAND (arg, 0), | |
2554 | TREE_OPERAND (arg, 1), 0)) | |
2555 | return 0; | |
2556 | ||
2557 | if (*cval1 == 0) | |
2558 | *cval1 = TREE_OPERAND (arg, 0); | |
2559 | else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0)) | |
2560 | ; | |
2561 | else if (*cval2 == 0) | |
2562 | *cval2 = TREE_OPERAND (arg, 0); | |
2563 | else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0)) | |
2564 | ; | |
2565 | else | |
2566 | return 0; | |
2567 | ||
2568 | if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0)) | |
2569 | ; | |
2570 | else if (*cval2 == 0) | |
2571 | *cval2 = TREE_OPERAND (arg, 1); | |
2572 | else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0)) | |
2573 | ; | |
2574 | else | |
2575 | return 0; | |
2576 | ||
2577 | return 1; | |
c05a9b68 | 2578 | |
e9a25f70 JL |
2579 | default: |
2580 | return 0; | |
2581 | } | |
c05a9b68 RS |
2582 | } |
2583 | \f | |
2584 | /* ARG is a tree that is known to contain just arithmetic operations and | |
2585 | comparisons. Evaluate the operations in the tree substituting NEW0 for | |
f72aed24 | 2586 | any occurrence of OLD0 as an operand of a comparison and likewise for |
c05a9b68 RS |
2587 | NEW1 and OLD1. */ |
2588 | ||
2589 | static tree | |
2590 | eval_subst (arg, old0, new0, old1, new1) | |
2591 | tree arg; | |
2592 | tree old0, new0, old1, new1; | |
2593 | { | |
2594 | tree type = TREE_TYPE (arg); | |
2595 | enum tree_code code = TREE_CODE (arg); | |
2596 | char class = TREE_CODE_CLASS (code); | |
2597 | ||
2598 | /* We can handle some of the 'e' cases here. */ | |
2599 | if (class == 'e' && code == TRUTH_NOT_EXPR) | |
2600 | class = '1'; | |
2601 | else if (class == 'e' | |
2602 | && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)) | |
2603 | class = '2'; | |
2604 | ||
2605 | switch (class) | |
2606 | { | |
2607 | case '1': | |
2608 | return fold (build1 (code, type, | |
2609 | eval_subst (TREE_OPERAND (arg, 0), | |
2610 | old0, new0, old1, new1))); | |
2611 | ||
2612 | case '2': | |
2613 | return fold (build (code, type, | |
2614 | eval_subst (TREE_OPERAND (arg, 0), | |
2615 | old0, new0, old1, new1), | |
2616 | eval_subst (TREE_OPERAND (arg, 1), | |
2617 | old0, new0, old1, new1))); | |
2618 | ||
2619 | case 'e': | |
2620 | switch (code) | |
2621 | { | |
2622 | case SAVE_EXPR: | |
2623 | return eval_subst (TREE_OPERAND (arg, 0), old0, new0, old1, new1); | |
2624 | ||
2625 | case COMPOUND_EXPR: | |
2626 | return eval_subst (TREE_OPERAND (arg, 1), old0, new0, old1, new1); | |
2627 | ||
2628 | case COND_EXPR: | |
2629 | return fold (build (code, type, | |
2630 | eval_subst (TREE_OPERAND (arg, 0), | |
2631 | old0, new0, old1, new1), | |
2632 | eval_subst (TREE_OPERAND (arg, 1), | |
2633 | old0, new0, old1, new1), | |
2634 | eval_subst (TREE_OPERAND (arg, 2), | |
2635 | old0, new0, old1, new1))); | |
e9a25f70 JL |
2636 | default: |
2637 | break; | |
c05a9b68 | 2638 | } |
e45ed4de | 2639 | /* fall through - ??? */ |
c05a9b68 RS |
2640 | |
2641 | case '<': | |
2642 | { | |
2643 | tree arg0 = TREE_OPERAND (arg, 0); | |
2644 | tree arg1 = TREE_OPERAND (arg, 1); | |
2645 | ||
2646 | /* We need to check both for exact equality and tree equality. The | |
2647 | former will be true if the operand has a side-effect. In that | |
2648 | case, we know the operand occurred exactly once. */ | |
2649 | ||
2650 | if (arg0 == old0 || operand_equal_p (arg0, old0, 0)) | |
2651 | arg0 = new0; | |
2652 | else if (arg0 == old1 || operand_equal_p (arg0, old1, 0)) | |
2653 | arg0 = new1; | |
2654 | ||
2655 | if (arg1 == old0 || operand_equal_p (arg1, old0, 0)) | |
2656 | arg1 = new0; | |
2657 | else if (arg1 == old1 || operand_equal_p (arg1, old1, 0)) | |
2658 | arg1 = new1; | |
2659 | ||
2660 | return fold (build (code, type, arg0, arg1)); | |
2661 | } | |
c05a9b68 | 2662 | |
e9a25f70 JL |
2663 | default: |
2664 | return arg; | |
2665 | } | |
c05a9b68 RS |
2666 | } |
2667 | \f | |
6d716ca8 RS |
2668 | /* Return a tree for the case when the result of an expression is RESULT |
2669 | converted to TYPE and OMITTED was previously an operand of the expression | |
2670 | but is now not needed (e.g., we folded OMITTED * 0). | |
2671 | ||
2672 | If OMITTED has side effects, we must evaluate it. Otherwise, just do | |
2673 | the conversion of RESULT to TYPE. */ | |
2674 | ||
2675 | static tree | |
2676 | omit_one_operand (type, result, omitted) | |
2677 | tree type, result, omitted; | |
2678 | { | |
2679 | tree t = convert (type, result); | |
2680 | ||
2681 | if (TREE_SIDE_EFFECTS (omitted)) | |
2682 | return build (COMPOUND_EXPR, type, omitted, t); | |
2683 | ||
d023bff9 | 2684 | return non_lvalue (t); |
6d716ca8 | 2685 | } |
4ab3cb65 RK |
2686 | |
2687 | /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */ | |
2688 | ||
2689 | static tree | |
2690 | pedantic_omit_one_operand (type, result, omitted) | |
2691 | tree type, result, omitted; | |
2692 | { | |
2693 | tree t = convert (type, result); | |
2694 | ||
2695 | if (TREE_SIDE_EFFECTS (omitted)) | |
2696 | return build (COMPOUND_EXPR, type, omitted, t); | |
2697 | ||
2698 | return pedantic_non_lvalue (t); | |
2699 | } | |
6d716ca8 | 2700 | \f |
3f783329 RS |
2701 | /* Return a simplified tree node for the truth-negation of ARG. This |
2702 | never alters ARG itself. We assume that ARG is an operation that | |
6d716ca8 RS |
2703 | returns a truth value (0 or 1). */ |
2704 | ||
2705 | tree | |
2706 | invert_truthvalue (arg) | |
2707 | tree arg; | |
2708 | { | |
2709 | tree type = TREE_TYPE (arg); | |
c05a9b68 | 2710 | enum tree_code code = TREE_CODE (arg); |
6d716ca8 | 2711 | |
8ac1abdf JW |
2712 | if (code == ERROR_MARK) |
2713 | return arg; | |
2714 | ||
c05a9b68 RS |
2715 | /* If this is a comparison, we can simply invert it, except for |
2716 | floating-point non-equality comparisons, in which case we just | |
2717 | enclose a TRUTH_NOT_EXPR around what we have. */ | |
6d716ca8 | 2718 | |
c05a9b68 | 2719 | if (TREE_CODE_CLASS (code) == '<') |
6d716ca8 | 2720 | { |
7178e3af | 2721 | if (FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg, 0))) |
de6c5979 BL |
2722 | && !flag_unsafe_math_optimizations |
2723 | && code != NE_EXPR | |
2724 | && code != EQ_EXPR) | |
c05a9b68 RS |
2725 | return build1 (TRUTH_NOT_EXPR, type, arg); |
2726 | else | |
ca46db87 | 2727 | return build (invert_tree_comparison (code), type, |
3f783329 | 2728 | TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1)); |
c05a9b68 | 2729 | } |
6d716ca8 | 2730 | |
c05a9b68 RS |
2731 | switch (code) |
2732 | { | |
6d716ca8 | 2733 | case INTEGER_CST: |
05bccae2 | 2734 | return convert (type, build_int_2 (integer_zerop (arg), 0)); |
6d716ca8 RS |
2735 | |
2736 | case TRUTH_AND_EXPR: | |
2737 | return build (TRUTH_OR_EXPR, type, | |
2738 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2739 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2740 | ||
2741 | case TRUTH_OR_EXPR: | |
2742 | return build (TRUTH_AND_EXPR, type, | |
2743 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2744 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2745 | ||
772447c5 RK |
2746 | case TRUTH_XOR_EXPR: |
2747 | /* Here we can invert either operand. We invert the first operand | |
2748 | unless the second operand is a TRUTH_NOT_EXPR in which case our | |
2749 | result is the XOR of the first operand with the inside of the | |
2750 | negation of the second operand. */ | |
2751 | ||
2752 | if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR) | |
2753 | return build (TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0), | |
2754 | TREE_OPERAND (TREE_OPERAND (arg, 1), 0)); | |
2755 | else | |
2756 | return build (TRUTH_XOR_EXPR, type, | |
2757 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2758 | TREE_OPERAND (arg, 1)); | |
2759 | ||
6d716ca8 RS |
2760 | case TRUTH_ANDIF_EXPR: |
2761 | return build (TRUTH_ORIF_EXPR, type, | |
2762 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2763 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2764 | ||
2765 | case TRUTH_ORIF_EXPR: | |
2766 | return build (TRUTH_ANDIF_EXPR, type, | |
2767 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2768 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2769 | ||
2770 | case TRUTH_NOT_EXPR: | |
2771 | return TREE_OPERAND (arg, 0); | |
2772 | ||
2773 | case COND_EXPR: | |
2774 | return build (COND_EXPR, type, TREE_OPERAND (arg, 0), | |
2775 | invert_truthvalue (TREE_OPERAND (arg, 1)), | |
2776 | invert_truthvalue (TREE_OPERAND (arg, 2))); | |
2777 | ||
ef9fe0da RK |
2778 | case COMPOUND_EXPR: |
2779 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg, 0), | |
2780 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2781 | ||
14a774a9 RK |
2782 | case WITH_RECORD_EXPR: |
2783 | return build (WITH_RECORD_EXPR, type, | |
2784 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2785 | TREE_OPERAND (arg, 1)); | |
2786 | ||
6d716ca8 RS |
2787 | case NON_LVALUE_EXPR: |
2788 | return invert_truthvalue (TREE_OPERAND (arg, 0)); | |
2789 | ||
2790 | case NOP_EXPR: | |
2791 | case CONVERT_EXPR: | |
2792 | case FLOAT_EXPR: | |
2793 | return build1 (TREE_CODE (arg), type, | |
2794 | invert_truthvalue (TREE_OPERAND (arg, 0))); | |
2795 | ||
2796 | case BIT_AND_EXPR: | |
efc1a4d9 PB |
2797 | if (!integer_onep (TREE_OPERAND (arg, 1))) |
2798 | break; | |
6d716ca8 | 2799 | return build (EQ_EXPR, type, arg, convert (type, integer_zero_node)); |
6d716ca8 | 2800 | |
dfa90b42 RS |
2801 | case SAVE_EXPR: |
2802 | return build1 (TRUTH_NOT_EXPR, type, arg); | |
a25ee332 RK |
2803 | |
2804 | case CLEANUP_POINT_EXPR: | |
2805 | return build1 (CLEANUP_POINT_EXPR, type, | |
2806 | invert_truthvalue (TREE_OPERAND (arg, 0))); | |
e9a25f70 JL |
2807 | |
2808 | default: | |
2809 | break; | |
efc1a4d9 PB |
2810 | } |
2811 | if (TREE_CODE (TREE_TYPE (arg)) != BOOLEAN_TYPE) | |
dfa90b42 | 2812 | abort (); |
efc1a4d9 | 2813 | return build1 (TRUTH_NOT_EXPR, type, arg); |
6d716ca8 RS |
2814 | } |
2815 | ||
2816 | /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both | |
2817 | operands are another bit-wise operation with a common input. If so, | |
2818 | distribute the bit operations to save an operation and possibly two if | |
2819 | constants are involved. For example, convert | |
2820 | (A | B) & (A | C) into A | (B & C) | |
2821 | Further simplification will occur if B and C are constants. | |
2822 | ||
2823 | If this optimization cannot be done, 0 will be returned. */ | |
2824 | ||
2825 | static tree | |
2826 | distribute_bit_expr (code, type, arg0, arg1) | |
2827 | enum tree_code code; | |
2828 | tree type; | |
2829 | tree arg0, arg1; | |
2830 | { | |
2831 | tree common; | |
2832 | tree left, right; | |
2833 | ||
2834 | if (TREE_CODE (arg0) != TREE_CODE (arg1) | |
2835 | || TREE_CODE (arg0) == code | |
fced8ba3 RS |
2836 | || (TREE_CODE (arg0) != BIT_AND_EXPR |
2837 | && TREE_CODE (arg0) != BIT_IOR_EXPR)) | |
6d716ca8 RS |
2838 | return 0; |
2839 | ||
2840 | if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0)) | |
2841 | { | |
2842 | common = TREE_OPERAND (arg0, 0); | |
2843 | left = TREE_OPERAND (arg0, 1); | |
2844 | right = TREE_OPERAND (arg1, 1); | |
2845 | } | |
2846 | else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0)) | |
2847 | { | |
2848 | common = TREE_OPERAND (arg0, 0); | |
2849 | left = TREE_OPERAND (arg0, 1); | |
2850 | right = TREE_OPERAND (arg1, 0); | |
2851 | } | |
2852 | else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0)) | |
2853 | { | |
2854 | common = TREE_OPERAND (arg0, 1); | |
2855 | left = TREE_OPERAND (arg0, 0); | |
2856 | right = TREE_OPERAND (arg1, 1); | |
2857 | } | |
2858 | else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0)) | |
2859 | { | |
2860 | common = TREE_OPERAND (arg0, 1); | |
2861 | left = TREE_OPERAND (arg0, 0); | |
2862 | right = TREE_OPERAND (arg1, 0); | |
2863 | } | |
2864 | else | |
2865 | return 0; | |
2866 | ||
2867 | return fold (build (TREE_CODE (arg0), type, common, | |
2868 | fold (build (code, type, left, right)))); | |
2869 | } | |
2870 | \f | |
2871 | /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER | |
2872 | starting at BITPOS. The field is unsigned if UNSIGNEDP is non-zero. */ | |
2873 | ||
2874 | static tree | |
2875 | make_bit_field_ref (inner, type, bitsize, bitpos, unsignedp) | |
2876 | tree inner; | |
2877 | tree type; | |
2878 | int bitsize, bitpos; | |
2879 | int unsignedp; | |
2880 | { | |
2881 | tree result = build (BIT_FIELD_REF, type, inner, | |
06ceef4e | 2882 | size_int (bitsize), bitsize_int (bitpos)); |
6d716ca8 RS |
2883 | |
2884 | TREE_UNSIGNED (result) = unsignedp; | |
2885 | ||
2886 | return result; | |
2887 | } | |
2888 | ||
2889 | /* Optimize a bit-field compare. | |
2890 | ||
2891 | There are two cases: First is a compare against a constant and the | |
2892 | second is a comparison of two items where the fields are at the same | |
2893 | bit position relative to the start of a chunk (byte, halfword, word) | |
2894 | large enough to contain it. In these cases we can avoid the shift | |
2895 | implicit in bitfield extractions. | |
2896 | ||
2897 | For constants, we emit a compare of the shifted constant with the | |
2898 | BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being | |
2899 | compared. For two fields at the same position, we do the ANDs with the | |
2900 | similar mask and compare the result of the ANDs. | |
2901 | ||
2902 | CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR. | |
2903 | COMPARE_TYPE is the type of the comparison, and LHS and RHS | |
2904 | are the left and right operands of the comparison, respectively. | |
2905 | ||
6dc42e49 | 2906 | If the optimization described above can be done, we return the resulting |
6d716ca8 RS |
2907 | tree. Otherwise we return zero. */ |
2908 | ||
2909 | static tree | |
2910 | optimize_bit_field_compare (code, compare_type, lhs, rhs) | |
2911 | enum tree_code code; | |
2912 | tree compare_type; | |
2913 | tree lhs, rhs; | |
2914 | { | |
770ae6cc | 2915 | HOST_WIDE_INT lbitpos, lbitsize, rbitpos, rbitsize, nbitpos, nbitsize; |
6d716ca8 RS |
2916 | tree type = TREE_TYPE (lhs); |
2917 | tree signed_type, unsigned_type; | |
2918 | int const_p = TREE_CODE (rhs) == INTEGER_CST; | |
5826cacf | 2919 | enum machine_mode lmode, rmode, nmode; |
6d716ca8 RS |
2920 | int lunsignedp, runsignedp; |
2921 | int lvolatilep = 0, rvolatilep = 0; | |
770ae6cc | 2922 | unsigned int alignment; |
4e86caed | 2923 | tree linner, rinner = NULL_TREE; |
6d716ca8 | 2924 | tree mask; |
f1e60ec6 | 2925 | tree offset; |
6d716ca8 RS |
2926 | |
2927 | /* Get all the information about the extractions being done. If the bit size | |
2928 | if the same as the size of the underlying object, we aren't doing an | |
14a774a9 RK |
2929 | extraction at all and so can do nothing. We also don't want to |
2930 | do anything if the inner expression is a PLACEHOLDER_EXPR since we | |
2931 | then will no longer be able to replace it. */ | |
f1e60ec6 | 2932 | linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode, |
23bd99ae | 2933 | &lunsignedp, &lvolatilep, &alignment); |
9f5e873c | 2934 | if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0 |
14a774a9 | 2935 | || offset != 0 || TREE_CODE (linner) == PLACEHOLDER_EXPR) |
6d716ca8 RS |
2936 | return 0; |
2937 | ||
2938 | if (!const_p) | |
2939 | { | |
2940 | /* If this is not a constant, we can only do something if bit positions, | |
2941 | sizes, and signedness are the same. */ | |
23bd99ae RK |
2942 | rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode, |
2943 | &runsignedp, &rvolatilep, &alignment); | |
6d716ca8 | 2944 | |
9f5e873c | 2945 | if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize |
14a774a9 RK |
2946 | || lunsignedp != runsignedp || offset != 0 |
2947 | || TREE_CODE (rinner) == PLACEHOLDER_EXPR) | |
6d716ca8 RS |
2948 | return 0; |
2949 | } | |
2950 | ||
2951 | /* See if we can find a mode to refer to this field. We should be able to, | |
2952 | but fail if we can't. */ | |
5826cacf RK |
2953 | nmode = get_best_mode (lbitsize, lbitpos, |
2954 | const_p ? TYPE_ALIGN (TREE_TYPE (linner)) | |
2955 | : MIN (TYPE_ALIGN (TREE_TYPE (linner)), | |
2956 | TYPE_ALIGN (TREE_TYPE (rinner))), | |
2957 | word_mode, lvolatilep || rvolatilep); | |
2958 | if (nmode == VOIDmode) | |
6d716ca8 RS |
2959 | return 0; |
2960 | ||
2961 | /* Set signed and unsigned types of the precision of this mode for the | |
2962 | shifts below. */ | |
5826cacf RK |
2963 | signed_type = type_for_mode (nmode, 0); |
2964 | unsigned_type = type_for_mode (nmode, 1); | |
6d716ca8 | 2965 | |
6d716ca8 RS |
2966 | /* Compute the bit position and size for the new reference and our offset |
2967 | within it. If the new reference is the same size as the original, we | |
2968 | won't optimize anything, so return zero. */ | |
5826cacf RK |
2969 | nbitsize = GET_MODE_BITSIZE (nmode); |
2970 | nbitpos = lbitpos & ~ (nbitsize - 1); | |
2971 | lbitpos -= nbitpos; | |
2972 | if (nbitsize == lbitsize) | |
6d716ca8 RS |
2973 | return 0; |
2974 | ||
f76b9db2 | 2975 | if (BYTES_BIG_ENDIAN) |
5826cacf | 2976 | lbitpos = nbitsize - lbitsize - lbitpos; |
6d716ca8 RS |
2977 | |
2978 | /* Make the mask to be used against the extracted field. */ | |
13af526d RS |
2979 | mask = build_int_2 (~0, ~0); |
2980 | TREE_TYPE (mask) = unsigned_type; | |
aa830baf | 2981 | force_fit_type (mask, 0); |
13af526d | 2982 | mask = convert (unsigned_type, mask); |
5826cacf | 2983 | mask = const_binop (LSHIFT_EXPR, mask, size_int (nbitsize - lbitsize), 0); |
6d716ca8 | 2984 | mask = const_binop (RSHIFT_EXPR, mask, |
5826cacf | 2985 | size_int (nbitsize - lbitsize - lbitpos), 0); |
6d716ca8 RS |
2986 | |
2987 | if (! const_p) | |
2988 | /* If not comparing with constant, just rework the comparison | |
2989 | and return. */ | |
2990 | return build (code, compare_type, | |
c0b9d4c8 RK |
2991 | build (BIT_AND_EXPR, unsigned_type, |
2992 | make_bit_field_ref (linner, unsigned_type, | |
5826cacf | 2993 | nbitsize, nbitpos, 1), |
6d716ca8 | 2994 | mask), |
c0b9d4c8 RK |
2995 | build (BIT_AND_EXPR, unsigned_type, |
2996 | make_bit_field_ref (rinner, unsigned_type, | |
5826cacf | 2997 | nbitsize, nbitpos, 1), |
6d716ca8 RS |
2998 | mask)); |
2999 | ||
3000 | /* Otherwise, we are handling the constant case. See if the constant is too | |
3001 | big for the field. Warn and return a tree of for 0 (false) if so. We do | |
3002 | this not only for its own sake, but to avoid having to test for this | |
3003 | error case below. If we didn't, we might generate wrong code. | |
3004 | ||
3005 | For unsigned fields, the constant shifted right by the field length should | |
b6cc0a72 | 3006 | be all zero. For signed fields, the high-order bits should agree with |
6d716ca8 RS |
3007 | the sign bit. */ |
3008 | ||
3009 | if (lunsignedp) | |
3010 | { | |
3011 | if (! integer_zerop (const_binop (RSHIFT_EXPR, | |
3012 | convert (unsigned_type, rhs), | |
91d33e36 | 3013 | size_int (lbitsize), 0))) |
6d716ca8 | 3014 | { |
ab87f8c8 JL |
3015 | warning ("comparison is always %d due to width of bitfield", |
3016 | code == NE_EXPR); | |
6d716ca8 RS |
3017 | return convert (compare_type, |
3018 | (code == NE_EXPR | |
3019 | ? integer_one_node : integer_zero_node)); | |
3020 | } | |
3021 | } | |
3022 | else | |
3023 | { | |
3024 | tree tem = const_binop (RSHIFT_EXPR, convert (signed_type, rhs), | |
91d33e36 | 3025 | size_int (lbitsize - 1), 0); |
6d716ca8 RS |
3026 | if (! integer_zerop (tem) && ! integer_all_onesp (tem)) |
3027 | { | |
ab87f8c8 JL |
3028 | warning ("comparison is always %d due to width of bitfield", |
3029 | code == NE_EXPR); | |
6d716ca8 RS |
3030 | return convert (compare_type, |
3031 | (code == NE_EXPR | |
3032 | ? integer_one_node : integer_zero_node)); | |
3033 | } | |
3034 | } | |
3035 | ||
3036 | /* Single-bit compares should always be against zero. */ | |
3037 | if (lbitsize == 1 && ! integer_zerop (rhs)) | |
3038 | { | |
3039 | code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR; | |
3040 | rhs = convert (type, integer_zero_node); | |
3041 | } | |
3042 | ||
3043 | /* Make a new bitfield reference, shift the constant over the | |
3044 | appropriate number of bits and mask it with the computed mask | |
3045 | (in case this was a signed field). If we changed it, make a new one. */ | |
5826cacf | 3046 | lhs = make_bit_field_ref (linner, unsigned_type, nbitsize, nbitpos, 1); |
9db73acb RK |
3047 | if (lvolatilep) |
3048 | { | |
3049 | TREE_SIDE_EFFECTS (lhs) = 1; | |
3050 | TREE_THIS_VOLATILE (lhs) = 1; | |
3051 | } | |
6d716ca8 | 3052 | |
c0b9d4c8 RK |
3053 | rhs = fold (const_binop (BIT_AND_EXPR, |
3054 | const_binop (LSHIFT_EXPR, | |
3055 | convert (unsigned_type, rhs), | |
194c082f | 3056 | size_int (lbitpos), 0), |
91d33e36 | 3057 | mask, 0)); |
6d716ca8 RS |
3058 | |
3059 | return build (code, compare_type, | |
c0b9d4c8 | 3060 | build (BIT_AND_EXPR, unsigned_type, lhs, mask), |
6d716ca8 RS |
3061 | rhs); |
3062 | } | |
3063 | \f | |
b2215d83 | 3064 | /* Subroutine for fold_truthop: decode a field reference. |
6d716ca8 RS |
3065 | |
3066 | If EXP is a comparison reference, we return the innermost reference. | |
3067 | ||
3068 | *PBITSIZE is set to the number of bits in the reference, *PBITPOS is | |
3069 | set to the starting bit number. | |
3070 | ||
3071 | If the innermost field can be completely contained in a mode-sized | |
3072 | unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode. | |
3073 | ||
3074 | *PVOLATILEP is set to 1 if the any expression encountered is volatile; | |
3075 | otherwise it is not changed. | |
3076 | ||
3077 | *PUNSIGNEDP is set to the signedness of the field. | |
3078 | ||
3079 | *PMASK is set to the mask used. This is either contained in a | |
3080 | BIT_AND_EXPR or derived from the width of the field. | |
3081 | ||
38e01259 | 3082 | *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any. |
d4453ee5 | 3083 | |
6d716ca8 RS |
3084 | Return 0 if this is not a component reference or is one that we can't |
3085 | do anything with. */ | |
3086 | ||
3087 | static tree | |
3088 | decode_field_reference (exp, pbitsize, pbitpos, pmode, punsignedp, | |
d4453ee5 | 3089 | pvolatilep, pmask, pand_mask) |
6d716ca8 | 3090 | tree exp; |
770ae6cc | 3091 | HOST_WIDE_INT *pbitsize, *pbitpos; |
6d716ca8 RS |
3092 | enum machine_mode *pmode; |
3093 | int *punsignedp, *pvolatilep; | |
3094 | tree *pmask; | |
d4453ee5 | 3095 | tree *pand_mask; |
6d716ca8 | 3096 | { |
6d9f1f5f RK |
3097 | tree and_mask = 0; |
3098 | tree mask, inner, offset; | |
3099 | tree unsigned_type; | |
770ae6cc RK |
3100 | unsigned int precision; |
3101 | unsigned int alignment; | |
6d716ca8 | 3102 | |
b6cc0a72 | 3103 | /* All the optimizations using this function assume integer fields. |
772ae9f0 RK |
3104 | There are problems with FP fields since the type_for_size call |
3105 | below can fail for, e.g., XFmode. */ | |
3106 | if (! INTEGRAL_TYPE_P (TREE_TYPE (exp))) | |
3107 | return 0; | |
3108 | ||
6d716ca8 RS |
3109 | STRIP_NOPS (exp); |
3110 | ||
3111 | if (TREE_CODE (exp) == BIT_AND_EXPR) | |
3112 | { | |
6d9f1f5f | 3113 | and_mask = TREE_OPERAND (exp, 1); |
6d716ca8 | 3114 | exp = TREE_OPERAND (exp, 0); |
6d9f1f5f RK |
3115 | STRIP_NOPS (exp); STRIP_NOPS (and_mask); |
3116 | if (TREE_CODE (and_mask) != INTEGER_CST) | |
6d716ca8 RS |
3117 | return 0; |
3118 | } | |
3119 | ||
f1e60ec6 | 3120 | inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode, |
23bd99ae | 3121 | punsignedp, pvolatilep, &alignment); |
02103577 | 3122 | if ((inner == exp && and_mask == 0) |
14a774a9 RK |
3123 | || *pbitsize < 0 || offset != 0 |
3124 | || TREE_CODE (inner) == PLACEHOLDER_EXPR) | |
c05a9b68 | 3125 | return 0; |
b6cc0a72 | 3126 | |
6d9f1f5f RK |
3127 | /* Compute the mask to access the bitfield. */ |
3128 | unsigned_type = type_for_size (*pbitsize, 1); | |
3129 | precision = TYPE_PRECISION (unsigned_type); | |
3130 | ||
3131 | mask = build_int_2 (~0, ~0); | |
3132 | TREE_TYPE (mask) = unsigned_type; | |
3133 | force_fit_type (mask, 0); | |
3134 | mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0); | |
3135 | mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0); | |
3136 | ||
3137 | /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */ | |
3138 | if (and_mask != 0) | |
3139 | mask = fold (build (BIT_AND_EXPR, unsigned_type, | |
3140 | convert (unsigned_type, and_mask), mask)); | |
6d716ca8 RS |
3141 | |
3142 | *pmask = mask; | |
d4453ee5 | 3143 | *pand_mask = and_mask; |
6d716ca8 RS |
3144 | return inner; |
3145 | } | |
3146 | ||
6dc42e49 | 3147 | /* Return non-zero if MASK represents a mask of SIZE ones in the low-order |
6d716ca8 RS |
3148 | bit positions. */ |
3149 | ||
3150 | static int | |
3151 | all_ones_mask_p (mask, size) | |
3152 | tree mask; | |
3153 | int size; | |
3154 | { | |
3155 | tree type = TREE_TYPE (mask); | |
770ae6cc | 3156 | unsigned int precision = TYPE_PRECISION (type); |
13af526d | 3157 | tree tmask; |
6d716ca8 | 3158 | |
13af526d RS |
3159 | tmask = build_int_2 (~0, ~0); |
3160 | TREE_TYPE (tmask) = signed_type (type); | |
aa830baf | 3161 | force_fit_type (tmask, 0); |
6d716ca8 | 3162 | return |
b6cc0a72 | 3163 | tree_int_cst_equal (mask, |
02103577 RK |
3164 | const_binop (RSHIFT_EXPR, |
3165 | const_binop (LSHIFT_EXPR, tmask, | |
3166 | size_int (precision - size), | |
3167 | 0), | |
3168 | size_int (precision - size), 0)); | |
6d716ca8 | 3169 | } |
b2215d83 TW |
3170 | |
3171 | /* Subroutine for fold_truthop: determine if an operand is simple enough | |
3172 | to be evaluated unconditionally. */ | |
3173 | ||
b6cc0a72 | 3174 | static int |
b2215d83 TW |
3175 | simple_operand_p (exp) |
3176 | tree exp; | |
3177 | { | |
3178 | /* Strip any conversions that don't change the machine mode. */ | |
3179 | while ((TREE_CODE (exp) == NOP_EXPR | |
3180 | || TREE_CODE (exp) == CONVERT_EXPR) | |
3181 | && (TYPE_MODE (TREE_TYPE (exp)) | |
3182 | == TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))))) | |
3183 | exp = TREE_OPERAND (exp, 0); | |
3184 | ||
3185 | return (TREE_CODE_CLASS (TREE_CODE (exp)) == 'c' | |
2f939d94 | 3186 | || (DECL_P (exp) |
b2215d83 TW |
3187 | && ! TREE_ADDRESSABLE (exp) |
3188 | && ! TREE_THIS_VOLATILE (exp) | |
8227896c TW |
3189 | && ! DECL_NONLOCAL (exp) |
3190 | /* Don't regard global variables as simple. They may be | |
3191 | allocated in ways unknown to the compiler (shared memory, | |
3192 | #pragma weak, etc). */ | |
3193 | && ! TREE_PUBLIC (exp) | |
3194 | && ! DECL_EXTERNAL (exp) | |
3195 | /* Loading a static variable is unduly expensive, but global | |
3196 | registers aren't expensive. */ | |
3197 | && (! TREE_STATIC (exp) || DECL_REGISTER (exp)))); | |
b2215d83 | 3198 | } |
6d716ca8 | 3199 | \f |
ebde8a27 RK |
3200 | /* The following functions are subroutines to fold_range_test and allow it to |
3201 | try to change a logical combination of comparisons into a range test. | |
3202 | ||
3203 | For example, both | |
f42ef510 | 3204 | X == 2 || X == 3 || X == 4 || X == 5 |
ebde8a27 RK |
3205 | and |
3206 | X >= 2 && X <= 5 | |
3207 | are converted to | |
3208 | (unsigned) (X - 2) <= 3 | |
3209 | ||
956d6950 | 3210 | We describe each set of comparisons as being either inside or outside |
ebde8a27 RK |
3211 | a range, using a variable named like IN_P, and then describe the |
3212 | range with a lower and upper bound. If one of the bounds is omitted, | |
3213 | it represents either the highest or lowest value of the type. | |
3214 | ||
3215 | In the comments below, we represent a range by two numbers in brackets | |
956d6950 | 3216 | preceded by a "+" to designate being inside that range, or a "-" to |
ebde8a27 RK |
3217 | designate being outside that range, so the condition can be inverted by |
3218 | flipping the prefix. An omitted bound is represented by a "-". For | |
3219 | example, "- [-, 10]" means being outside the range starting at the lowest | |
3220 | possible value and ending at 10, in other words, being greater than 10. | |
3221 | The range "+ [-, -]" is always true and hence the range "- [-, -]" is | |
3222 | always false. | |
3223 | ||
3224 | We set up things so that the missing bounds are handled in a consistent | |
3225 | manner so neither a missing bound nor "true" and "false" need to be | |
3226 | handled using a special case. */ | |
3227 | ||
3228 | /* Return the result of applying CODE to ARG0 and ARG1, but handle the case | |
3229 | of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P | |
3230 | and UPPER1_P are nonzero if the respective argument is an upper bound | |
3231 | and zero for a lower. TYPE, if nonzero, is the type of the result; it | |
3232 | must be specified for a comparison. ARG1 will be converted to ARG0's | |
3233 | type if both are specified. */ | |
ef659ec0 | 3234 | |
ebde8a27 RK |
3235 | static tree |
3236 | range_binop (code, type, arg0, upper0_p, arg1, upper1_p) | |
3237 | enum tree_code code; | |
3238 | tree type; | |
3239 | tree arg0, arg1; | |
3240 | int upper0_p, upper1_p; | |
3241 | { | |
27bae8e5 | 3242 | tree tem; |
ebde8a27 RK |
3243 | int result; |
3244 | int sgn0, sgn1; | |
ef659ec0 | 3245 | |
ebde8a27 RK |
3246 | /* If neither arg represents infinity, do the normal operation. |
3247 | Else, if not a comparison, return infinity. Else handle the special | |
3248 | comparison rules. Note that most of the cases below won't occur, but | |
3249 | are handled for consistency. */ | |
ef659ec0 | 3250 | |
ebde8a27 | 3251 | if (arg0 != 0 && arg1 != 0) |
27bae8e5 RK |
3252 | { |
3253 | tem = fold (build (code, type != 0 ? type : TREE_TYPE (arg0), | |
3254 | arg0, convert (TREE_TYPE (arg0), arg1))); | |
3255 | STRIP_NOPS (tem); | |
3256 | return TREE_CODE (tem) == INTEGER_CST ? tem : 0; | |
3257 | } | |
ef659ec0 | 3258 | |
ebde8a27 RK |
3259 | if (TREE_CODE_CLASS (code) != '<') |
3260 | return 0; | |
3261 | ||
3262 | /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0 | |
d7b3ea38 NS |
3263 | for neither. In real maths, we cannot assume open ended ranges are |
3264 | the same. But, this is computer arithmetic, where numbers are finite. | |
3265 | We can therefore make the transformation of any unbounded range with | |
3266 | the value Z, Z being greater than any representable number. This permits | |
3267 | us to treat unbounded ranges as equal. */ | |
ebde8a27 | 3268 | sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1); |
4e644c93 | 3269 | sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1); |
ebde8a27 RK |
3270 | switch (code) |
3271 | { | |
d7b3ea38 NS |
3272 | case EQ_EXPR: |
3273 | result = sgn0 == sgn1; | |
3274 | break; | |
3275 | case NE_EXPR: | |
3276 | result = sgn0 != sgn1; | |
ebde8a27 | 3277 | break; |
d7b3ea38 | 3278 | case LT_EXPR: |
ebde8a27 RK |
3279 | result = sgn0 < sgn1; |
3280 | break; | |
d7b3ea38 NS |
3281 | case LE_EXPR: |
3282 | result = sgn0 <= sgn1; | |
3283 | break; | |
3284 | case GT_EXPR: | |
ebde8a27 RK |
3285 | result = sgn0 > sgn1; |
3286 | break; | |
d7b3ea38 NS |
3287 | case GE_EXPR: |
3288 | result = sgn0 >= sgn1; | |
3289 | break; | |
e9a25f70 JL |
3290 | default: |
3291 | abort (); | |
ebde8a27 RK |
3292 | } |
3293 | ||
3294 | return convert (type, result ? integer_one_node : integer_zero_node); | |
3295 | } | |
b6cc0a72 | 3296 | \f |
ebde8a27 RK |
3297 | /* Given EXP, a logical expression, set the range it is testing into |
3298 | variables denoted by PIN_P, PLOW, and PHIGH. Return the expression | |
f42ef510 | 3299 | actually being tested. *PLOW and *PHIGH will be made of the same type |
ebde8a27 RK |
3300 | as the returned expression. If EXP is not a comparison, we will most |
3301 | likely not be returning a useful value and range. */ | |
ef659ec0 | 3302 | |
6dc7571d | 3303 | static tree |
ebde8a27 RK |
3304 | make_range (exp, pin_p, plow, phigh) |
3305 | tree exp; | |
3306 | int *pin_p; | |
3307 | tree *plow, *phigh; | |
ef659ec0 | 3308 | { |
ebde8a27 | 3309 | enum tree_code code; |
07444f1d | 3310 | tree arg0 = NULL_TREE, arg1 = NULL_TREE, type = NULL_TREE; |
7d12cee1 | 3311 | tree orig_type = NULL_TREE; |
ebde8a27 RK |
3312 | int in_p, n_in_p; |
3313 | tree low, high, n_low, n_high; | |
ef659ec0 | 3314 | |
ebde8a27 RK |
3315 | /* Start with simply saying "EXP != 0" and then look at the code of EXP |
3316 | and see if we can refine the range. Some of the cases below may not | |
3317 | happen, but it doesn't seem worth worrying about this. We "continue" | |
3318 | the outer loop when we've changed something; otherwise we "break" | |
3319 | the switch, which will "break" the while. */ | |
ef659ec0 | 3320 | |
ebde8a27 RK |
3321 | in_p = 0, low = high = convert (TREE_TYPE (exp), integer_zero_node); |
3322 | ||
3323 | while (1) | |
ef659ec0 | 3324 | { |
ebde8a27 | 3325 | code = TREE_CODE (exp); |
30d68b86 MM |
3326 | |
3327 | if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code))) | |
3328 | { | |
3329 | arg0 = TREE_OPERAND (exp, 0); | |
b6cc0a72 | 3330 | if (TREE_CODE_CLASS (code) == '<' |
30d68b86 MM |
3331 | || TREE_CODE_CLASS (code) == '1' |
3332 | || TREE_CODE_CLASS (code) == '2') | |
3333 | type = TREE_TYPE (arg0); | |
b6cc0a72 | 3334 | if (TREE_CODE_CLASS (code) == '2' |
30d68b86 | 3335 | || TREE_CODE_CLASS (code) == '<' |
b6cc0a72 | 3336 | || (TREE_CODE_CLASS (code) == 'e' |
efd58783 | 3337 | && TREE_CODE_LENGTH (code) > 1)) |
30d68b86 MM |
3338 | arg1 = TREE_OPERAND (exp, 1); |
3339 | } | |
ef659ec0 | 3340 | |
cc33944a RE |
3341 | /* Set ORIG_TYPE as soon as TYPE is non-null so that we do not |
3342 | lose a cast by accident. */ | |
3343 | if (type != NULL_TREE && orig_type == NULL_TREE) | |
3344 | orig_type = type; | |
3345 | ||
ebde8a27 RK |
3346 | switch (code) |
3347 | { | |
3348 | case TRUTH_NOT_EXPR: | |
3349 | in_p = ! in_p, exp = arg0; | |
3350 | continue; | |
3351 | ||
3352 | case EQ_EXPR: case NE_EXPR: | |
3353 | case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR: | |
3354 | /* We can only do something if the range is testing for zero | |
3355 | and if the second operand is an integer constant. Note that | |
3356 | saying something is "in" the range we make is done by | |
3357 | complementing IN_P since it will set in the initial case of | |
3358 | being not equal to zero; "out" is leaving it alone. */ | |
3359 | if (low == 0 || high == 0 | |
3360 | || ! integer_zerop (low) || ! integer_zerop (high) | |
3361 | || TREE_CODE (arg1) != INTEGER_CST) | |
3362 | break; | |
ef659ec0 | 3363 | |
ebde8a27 RK |
3364 | switch (code) |
3365 | { | |
3366 | case NE_EXPR: /* - [c, c] */ | |
3367 | low = high = arg1; | |
3368 | break; | |
3369 | case EQ_EXPR: /* + [c, c] */ | |
3370 | in_p = ! in_p, low = high = arg1; | |
3371 | break; | |
3372 | case GT_EXPR: /* - [-, c] */ | |
3373 | low = 0, high = arg1; | |
3374 | break; | |
3375 | case GE_EXPR: /* + [c, -] */ | |
3376 | in_p = ! in_p, low = arg1, high = 0; | |
3377 | break; | |
3378 | case LT_EXPR: /* - [c, -] */ | |
3379 | low = arg1, high = 0; | |
3380 | break; | |
3381 | case LE_EXPR: /* + [-, c] */ | |
3382 | in_p = ! in_p, low = 0, high = arg1; | |
3383 | break; | |
e9a25f70 JL |
3384 | default: |
3385 | abort (); | |
ebde8a27 | 3386 | } |
ef659ec0 | 3387 | |
ebde8a27 | 3388 | exp = arg0; |
ef659ec0 | 3389 | |
7f423031 | 3390 | /* If this is an unsigned comparison, we also know that EXP is |
0e1c7fc7 RK |
3391 | greater than or equal to zero. We base the range tests we make |
3392 | on that fact, so we record it here so we can parse existing | |
3393 | range tests. */ | |
7f423031 | 3394 | if (TREE_UNSIGNED (type) && (low == 0 || high == 0)) |
ebde8a27 RK |
3395 | { |
3396 | if (! merge_ranges (&n_in_p, &n_low, &n_high, in_p, low, high, | |
3397 | 1, convert (type, integer_zero_node), | |
0e1c7fc7 | 3398 | NULL_TREE)) |
ebde8a27 | 3399 | break; |
ef659ec0 | 3400 | |
ebde8a27 | 3401 | in_p = n_in_p, low = n_low, high = n_high; |
0e1c7fc7 | 3402 | |
c565a6b7 R |
3403 | /* If the high bound is missing, but we |
3404 | have a low bound, reverse the range so | |
3405 | it goes from zero to the low bound minus 1. */ | |
3406 | if (high == 0 && low) | |
0e1c7fc7 RK |
3407 | { |
3408 | in_p = ! in_p; | |
3409 | high = range_binop (MINUS_EXPR, NULL_TREE, low, 0, | |
3410 | integer_one_node, 0); | |
3411 | low = convert (type, integer_zero_node); | |
3412 | } | |
ebde8a27 RK |
3413 | } |
3414 | continue; | |
3415 | ||
3416 | case NEGATE_EXPR: | |
3417 | /* (-x) IN [a,b] -> x in [-b, -a] */ | |
3418 | n_low = range_binop (MINUS_EXPR, type, | |
3419 | convert (type, integer_zero_node), 0, high, 1); | |
3420 | n_high = range_binop (MINUS_EXPR, type, | |
3421 | convert (type, integer_zero_node), 0, low, 0); | |
3422 | low = n_low, high = n_high; | |
3423 | exp = arg0; | |
3424 | continue; | |
3425 | ||
3426 | case BIT_NOT_EXPR: | |
3427 | /* ~ X -> -X - 1 */ | |
1baa375f | 3428 | exp = build (MINUS_EXPR, type, negate_expr (arg0), |
27bae8e5 | 3429 | convert (type, integer_one_node)); |
ebde8a27 RK |
3430 | continue; |
3431 | ||
3432 | case PLUS_EXPR: case MINUS_EXPR: | |
3433 | if (TREE_CODE (arg1) != INTEGER_CST) | |
3434 | break; | |
3435 | ||
3436 | /* If EXP is signed, any overflow in the computation is undefined, | |
3437 | so we don't worry about it so long as our computations on | |
3438 | the bounds don't overflow. For unsigned, overflow is defined | |
3439 | and this is exactly the right thing. */ | |
3440 | n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR, | |
3441 | type, low, 0, arg1, 0); | |
3442 | n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR, | |
3443 | type, high, 1, arg1, 0); | |
3444 | if ((n_low != 0 && TREE_OVERFLOW (n_low)) | |
3445 | || (n_high != 0 && TREE_OVERFLOW (n_high))) | |
3446 | break; | |
3447 | ||
3c00684e JL |
3448 | /* Check for an unsigned range which has wrapped around the maximum |
3449 | value thus making n_high < n_low, and normalize it. */ | |
5a9d82a6 | 3450 | if (n_low && n_high && tree_int_cst_lt (n_high, n_low)) |
3c00684e JL |
3451 | { |
3452 | low = range_binop (PLUS_EXPR, type, n_high, 0, | |
0e1c7fc7 | 3453 | integer_one_node, 0); |
3c00684e | 3454 | high = range_binop (MINUS_EXPR, type, n_low, 0, |
c2b63960 AO |
3455 | integer_one_node, 0); |
3456 | ||
3457 | /* If the range is of the form +/- [ x+1, x ], we won't | |
3458 | be able to normalize it. But then, it represents the | |
3459 | whole range or the empty set, so make it | |
3460 | +/- [ -, - ]. */ | |
3461 | if (tree_int_cst_equal (n_low, low) | |
3462 | && tree_int_cst_equal (n_high, high)) | |
3463 | low = high = 0; | |
3464 | else | |
3465 | in_p = ! in_p; | |
3c00684e | 3466 | } |
5a9d82a6 JW |
3467 | else |
3468 | low = n_low, high = n_high; | |
27bae8e5 | 3469 | |
ebde8a27 RK |
3470 | exp = arg0; |
3471 | continue; | |
3472 | ||
3473 | case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR: | |
7d12cee1 JL |
3474 | if (TYPE_PRECISION (type) > TYPE_PRECISION (orig_type)) |
3475 | break; | |
3476 | ||
ebde8a27 RK |
3477 | if (! INTEGRAL_TYPE_P (type) |
3478 | || (low != 0 && ! int_fits_type_p (low, type)) | |
3479 | || (high != 0 && ! int_fits_type_p (high, type))) | |
3480 | break; | |
3481 | ||
ce2157a1 | 3482 | n_low = low, n_high = high; |
ebde8a27 | 3483 | |
ce2157a1 JL |
3484 | if (n_low != 0) |
3485 | n_low = convert (type, n_low); | |
3486 | ||
3487 | if (n_high != 0) | |
3488 | n_high = convert (type, n_high); | |
3489 | ||
3490 | /* If we're converting from an unsigned to a signed type, | |
3491 | we will be doing the comparison as unsigned. The tests above | |
3492 | have already verified that LOW and HIGH are both positive. | |
3493 | ||
3494 | So we have to make sure that the original unsigned value will | |
3495 | be interpreted as positive. */ | |
3496 | if (TREE_UNSIGNED (type) && ! TREE_UNSIGNED (TREE_TYPE (exp))) | |
3497 | { | |
3498 | tree equiv_type = type_for_mode (TYPE_MODE (type), 1); | |
e1ee5cdc RH |
3499 | tree high_positive; |
3500 | ||
3501 | /* A range without an upper bound is, naturally, unbounded. | |
3502 | Since convert would have cropped a very large value, use | |
14a774a9 RK |
3503 | the max value for the destination type. */ |
3504 | high_positive | |
3505 | = TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type) | |
3506 | : TYPE_MAX_VALUE (type); | |
e1ee5cdc | 3507 | |
e1ee5cdc RH |
3508 | high_positive = fold (build (RSHIFT_EXPR, type, |
3509 | convert (type, high_positive), | |
3510 | convert (type, integer_one_node))); | |
b6cc0a72 | 3511 | |
ce2157a1 JL |
3512 | /* If the low bound is specified, "and" the range with the |
3513 | range for which the original unsigned value will be | |
3514 | positive. */ | |
3515 | if (low != 0) | |
3516 | { | |
3517 | if (! merge_ranges (&n_in_p, &n_low, &n_high, | |
3518 | 1, n_low, n_high, | |
3519 | 1, convert (type, integer_zero_node), | |
3520 | high_positive)) | |
3521 | break; | |
3522 | ||
3523 | in_p = (n_in_p == in_p); | |
3524 | } | |
3525 | else | |
3526 | { | |
3527 | /* Otherwise, "or" the range with the range of the input | |
3528 | that will be interpreted as negative. */ | |
3529 | if (! merge_ranges (&n_in_p, &n_low, &n_high, | |
3530 | 0, n_low, n_high, | |
3531 | 1, convert (type, integer_zero_node), | |
3532 | high_positive)) | |
3533 | break; | |
3534 | ||
3535 | in_p = (in_p != n_in_p); | |
3536 | } | |
3537 | } | |
ebde8a27 RK |
3538 | |
3539 | exp = arg0; | |
ce2157a1 | 3540 | low = n_low, high = n_high; |
ebde8a27 | 3541 | continue; |
ce2157a1 JL |
3542 | |
3543 | default: | |
3544 | break; | |
ef659ec0 | 3545 | } |
ebde8a27 RK |
3546 | |
3547 | break; | |
ef659ec0 | 3548 | } |
ebde8a27 | 3549 | |
80906567 RK |
3550 | /* If EXP is a constant, we can evaluate whether this is true or false. */ |
3551 | if (TREE_CODE (exp) == INTEGER_CST) | |
3552 | { | |
3553 | in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node, | |
3554 | exp, 0, low, 0)) | |
3555 | && integer_onep (range_binop (LE_EXPR, integer_type_node, | |
3556 | exp, 1, high, 1))); | |
3557 | low = high = 0; | |
3558 | exp = 0; | |
3559 | } | |
3560 | ||
ebde8a27 RK |
3561 | *pin_p = in_p, *plow = low, *phigh = high; |
3562 | return exp; | |
3563 | } | |
3564 | \f | |
3565 | /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result | |
3566 | type, TYPE, return an expression to test if EXP is in (or out of, depending | |
3567 | on IN_P) the range. */ | |
3568 | ||
3569 | static tree | |
3570 | build_range_check (type, exp, in_p, low, high) | |
3571 | tree type; | |
3572 | tree exp; | |
3573 | int in_p; | |
3574 | tree low, high; | |
3575 | { | |
3576 | tree etype = TREE_TYPE (exp); | |
3577 | tree utype, value; | |
3578 | ||
3579 | if (! in_p | |
3580 | && (0 != (value = build_range_check (type, exp, 1, low, high)))) | |
3581 | return invert_truthvalue (value); | |
3582 | ||
3583 | else if (low == 0 && high == 0) | |
3584 | return convert (type, integer_one_node); | |
3585 | ||
3586 | else if (low == 0) | |
3587 | return fold (build (LE_EXPR, type, exp, high)); | |
3588 | ||
3589 | else if (high == 0) | |
3590 | return fold (build (GE_EXPR, type, exp, low)); | |
3591 | ||
3592 | else if (operand_equal_p (low, high, 0)) | |
3593 | return fold (build (EQ_EXPR, type, exp, low)); | |
3594 | ||
3595 | else if (TREE_UNSIGNED (etype) && integer_zerop (low)) | |
3596 | return build_range_check (type, exp, 1, 0, high); | |
3597 | ||
3598 | else if (integer_zerop (low)) | |
ef659ec0 | 3599 | { |
ebde8a27 RK |
3600 | utype = unsigned_type (etype); |
3601 | return build_range_check (type, convert (utype, exp), 1, 0, | |
3602 | convert (utype, high)); | |
3603 | } | |
ef659ec0 | 3604 | |
ebde8a27 RK |
3605 | else if (0 != (value = const_binop (MINUS_EXPR, high, low, 0)) |
3606 | && ! TREE_OVERFLOW (value)) | |
3607 | return build_range_check (type, | |
3608 | fold (build (MINUS_EXPR, etype, exp, low)), | |
3609 | 1, convert (etype, integer_zero_node), value); | |
3610 | else | |
3611 | return 0; | |
3612 | } | |
3613 | \f | |
b6cc0a72 | 3614 | /* Given two ranges, see if we can merge them into one. Return 1 if we |
ebde8a27 | 3615 | can, 0 if we can't. Set the output range into the specified parameters. */ |
ef659ec0 | 3616 | |
ebde8a27 RK |
3617 | static int |
3618 | merge_ranges (pin_p, plow, phigh, in0_p, low0, high0, in1_p, low1, high1) | |
3619 | int *pin_p; | |
3620 | tree *plow, *phigh; | |
3621 | int in0_p, in1_p; | |
3622 | tree low0, high0, low1, high1; | |
3623 | { | |
3624 | int no_overlap; | |
3625 | int subset; | |
3626 | int temp; | |
3627 | tree tem; | |
3628 | int in_p; | |
3629 | tree low, high; | |
ce2157a1 JL |
3630 | int lowequal = ((low0 == 0 && low1 == 0) |
3631 | || integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3632 | low0, 0, low1, 0))); | |
3633 | int highequal = ((high0 == 0 && high1 == 0) | |
3634 | || integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3635 | high0, 1, high1, 1))); | |
3636 | ||
3637 | /* Make range 0 be the range that starts first, or ends last if they | |
3638 | start at the same value. Swap them if it isn't. */ | |
b6cc0a72 | 3639 | if (integer_onep (range_binop (GT_EXPR, integer_type_node, |
ebde8a27 | 3640 | low0, 0, low1, 0)) |
ce2157a1 | 3641 | || (lowequal |
ebde8a27 | 3642 | && integer_onep (range_binop (GT_EXPR, integer_type_node, |
ce2157a1 | 3643 | high1, 1, high0, 1)))) |
ebde8a27 RK |
3644 | { |
3645 | temp = in0_p, in0_p = in1_p, in1_p = temp; | |
3646 | tem = low0, low0 = low1, low1 = tem; | |
3647 | tem = high0, high0 = high1, high1 = tem; | |
3648 | } | |
ef659ec0 | 3649 | |
ebde8a27 RK |
3650 | /* Now flag two cases, whether the ranges are disjoint or whether the |
3651 | second range is totally subsumed in the first. Note that the tests | |
3652 | below are simplified by the ones above. */ | |
3653 | no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node, | |
3654 | high0, 1, low1, 0)); | |
5df8a1f2 | 3655 | subset = integer_onep (range_binop (LE_EXPR, integer_type_node, |
ebde8a27 RK |
3656 | high1, 1, high0, 1)); |
3657 | ||
3658 | /* We now have four cases, depending on whether we are including or | |
3659 | excluding the two ranges. */ | |
3660 | if (in0_p && in1_p) | |
3661 | { | |
3662 | /* If they don't overlap, the result is false. If the second range | |
3663 | is a subset it is the result. Otherwise, the range is from the start | |
3664 | of the second to the end of the first. */ | |
3665 | if (no_overlap) | |
3666 | in_p = 0, low = high = 0; | |
3667 | else if (subset) | |
3668 | in_p = 1, low = low1, high = high1; | |
3669 | else | |
3670 | in_p = 1, low = low1, high = high0; | |
3671 | } | |
ef659ec0 | 3672 | |
ebde8a27 RK |
3673 | else if (in0_p && ! in1_p) |
3674 | { | |
ce2157a1 JL |
3675 | /* If they don't overlap, the result is the first range. If they are |
3676 | equal, the result is false. If the second range is a subset of the | |
3677 | first, and the ranges begin at the same place, we go from just after | |
3678 | the end of the first range to the end of the second. If the second | |
3679 | range is not a subset of the first, or if it is a subset and both | |
3680 | ranges end at the same place, the range starts at the start of the | |
3681 | first range and ends just before the second range. | |
3682 | Otherwise, we can't describe this as a single range. */ | |
ebde8a27 RK |
3683 | if (no_overlap) |
3684 | in_p = 1, low = low0, high = high0; | |
ce2157a1 | 3685 | else if (lowequal && highequal) |
405862dd | 3686 | in_p = 0, low = high = 0; |
ce2157a1 JL |
3687 | else if (subset && lowequal) |
3688 | { | |
3689 | in_p = 1, high = high0; | |
3690 | low = range_binop (PLUS_EXPR, NULL_TREE, high1, 0, | |
b6cc0a72 | 3691 | integer_one_node, 0); |
ce2157a1 JL |
3692 | } |
3693 | else if (! subset || highequal) | |
ebde8a27 RK |
3694 | { |
3695 | in_p = 1, low = low0; | |
3696 | high = range_binop (MINUS_EXPR, NULL_TREE, low1, 0, | |
0e1c7fc7 | 3697 | integer_one_node, 0); |
ebde8a27 | 3698 | } |
ce2157a1 JL |
3699 | else |
3700 | return 0; | |
ebde8a27 | 3701 | } |
ef659ec0 | 3702 | |
ebde8a27 RK |
3703 | else if (! in0_p && in1_p) |
3704 | { | |
3705 | /* If they don't overlap, the result is the second range. If the second | |
3706 | is a subset of the first, the result is false. Otherwise, | |
3707 | the range starts just after the first range and ends at the | |
3708 | end of the second. */ | |
3709 | if (no_overlap) | |
3710 | in_p = 1, low = low1, high = high1; | |
14a774a9 | 3711 | else if (subset || highequal) |
ebde8a27 RK |
3712 | in_p = 0, low = high = 0; |
3713 | else | |
3714 | { | |
3715 | in_p = 1, high = high1; | |
3716 | low = range_binop (PLUS_EXPR, NULL_TREE, high0, 1, | |
3717 | integer_one_node, 0); | |
ef659ec0 TW |
3718 | } |
3719 | } | |
3720 | ||
ebde8a27 RK |
3721 | else |
3722 | { | |
3723 | /* The case where we are excluding both ranges. Here the complex case | |
3724 | is if they don't overlap. In that case, the only time we have a | |
3725 | range is if they are adjacent. If the second is a subset of the | |
3726 | first, the result is the first. Otherwise, the range to exclude | |
3727 | starts at the beginning of the first range and ends at the end of the | |
3728 | second. */ | |
3729 | if (no_overlap) | |
3730 | { | |
3731 | if (integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3732 | range_binop (PLUS_EXPR, NULL_TREE, | |
3733 | high0, 1, | |
3734 | integer_one_node, 1), | |
3735 | 1, low1, 0))) | |
3736 | in_p = 0, low = low0, high = high1; | |
3737 | else | |
3738 | return 0; | |
3739 | } | |
3740 | else if (subset) | |
3741 | in_p = 0, low = low0, high = high0; | |
3742 | else | |
3743 | in_p = 0, low = low0, high = high1; | |
3744 | } | |
f5902869 | 3745 | |
ebde8a27 RK |
3746 | *pin_p = in_p, *plow = low, *phigh = high; |
3747 | return 1; | |
3748 | } | |
3749 | \f | |
3750 | /* EXP is some logical combination of boolean tests. See if we can | |
3751 | merge it into some range test. Return the new tree if so. */ | |
ef659ec0 | 3752 | |
ebde8a27 RK |
3753 | static tree |
3754 | fold_range_test (exp) | |
3755 | tree exp; | |
3756 | { | |
3757 | int or_op = (TREE_CODE (exp) == TRUTH_ORIF_EXPR | |
3758 | || TREE_CODE (exp) == TRUTH_OR_EXPR); | |
3759 | int in0_p, in1_p, in_p; | |
3760 | tree low0, low1, low, high0, high1, high; | |
3761 | tree lhs = make_range (TREE_OPERAND (exp, 0), &in0_p, &low0, &high0); | |
3762 | tree rhs = make_range (TREE_OPERAND (exp, 1), &in1_p, &low1, &high1); | |
3763 | tree tem; | |
ef659ec0 | 3764 | |
ebde8a27 RK |
3765 | /* If this is an OR operation, invert both sides; we will invert |
3766 | again at the end. */ | |
3767 | if (or_op) | |
3768 | in0_p = ! in0_p, in1_p = ! in1_p; | |
3769 | ||
3770 | /* If both expressions are the same, if we can merge the ranges, and we | |
80906567 RK |
3771 | can build the range test, return it or it inverted. If one of the |
3772 | ranges is always true or always false, consider it to be the same | |
3773 | expression as the other. */ | |
3774 | if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0)) | |
ebde8a27 RK |
3775 | && merge_ranges (&in_p, &low, &high, in0_p, low0, high0, |
3776 | in1_p, low1, high1) | |
80906567 RK |
3777 | && 0 != (tem = (build_range_check (TREE_TYPE (exp), |
3778 | lhs != 0 ? lhs | |
3779 | : rhs != 0 ? rhs : integer_zero_node, | |
ebde8a27 RK |
3780 | in_p, low, high)))) |
3781 | return or_op ? invert_truthvalue (tem) : tem; | |
3782 | ||
3783 | /* On machines where the branch cost is expensive, if this is a | |
3784 | short-circuited branch and the underlying object on both sides | |
3785 | is the same, make a non-short-circuit operation. */ | |
3786 | else if (BRANCH_COST >= 2 | |
7cf5c9e1 | 3787 | && lhs != 0 && rhs != 0 |
ebde8a27 RK |
3788 | && (TREE_CODE (exp) == TRUTH_ANDIF_EXPR |
3789 | || TREE_CODE (exp) == TRUTH_ORIF_EXPR) | |
3790 | && operand_equal_p (lhs, rhs, 0)) | |
ef659ec0 | 3791 | { |
f0eebf28 | 3792 | /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR |
9ec36da5 JL |
3793 | unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in |
3794 | which cases we can't do this. */ | |
ebde8a27 RK |
3795 | if (simple_operand_p (lhs)) |
3796 | return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3797 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR, | |
3798 | TREE_TYPE (exp), TREE_OPERAND (exp, 0), | |
3799 | TREE_OPERAND (exp, 1)); | |
f0eebf28 | 3800 | |
c5c76735 | 3801 | else if (global_bindings_p () == 0 |
9ec36da5 | 3802 | && ! contains_placeholder_p (lhs)) |
ebde8a27 RK |
3803 | { |
3804 | tree common = save_expr (lhs); | |
3805 | ||
3806 | if (0 != (lhs = build_range_check (TREE_TYPE (exp), common, | |
3807 | or_op ? ! in0_p : in0_p, | |
3808 | low0, high0)) | |
3809 | && (0 != (rhs = build_range_check (TREE_TYPE (exp), common, | |
3810 | or_op ? ! in1_p : in1_p, | |
3811 | low1, high1)))) | |
3812 | return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3813 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR, | |
3814 | TREE_TYPE (exp), lhs, rhs); | |
3815 | } | |
ef659ec0 | 3816 | } |
de153e82 | 3817 | |
de153e82 | 3818 | return 0; |
ef659ec0 TW |
3819 | } |
3820 | \f | |
02103577 | 3821 | /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P |
25216284 | 3822 | bit value. Arrange things so the extra bits will be set to zero if and |
d4453ee5 RK |
3823 | only if C is signed-extended to its full width. If MASK is nonzero, |
3824 | it is an INTEGER_CST that should be AND'ed with the extra bits. */ | |
02103577 RK |
3825 | |
3826 | static tree | |
d4453ee5 | 3827 | unextend (c, p, unsignedp, mask) |
02103577 RK |
3828 | tree c; |
3829 | int p; | |
3830 | int unsignedp; | |
d4453ee5 | 3831 | tree mask; |
02103577 RK |
3832 | { |
3833 | tree type = TREE_TYPE (c); | |
3834 | int modesize = GET_MODE_BITSIZE (TYPE_MODE (type)); | |
3835 | tree temp; | |
3836 | ||
3837 | if (p == modesize || unsignedp) | |
3838 | return c; | |
3839 | ||
02103577 | 3840 | /* We work by getting just the sign bit into the low-order bit, then |
9faa82d8 | 3841 | into the high-order bit, then sign-extend. We then XOR that value |
02103577 RK |
3842 | with C. */ |
3843 | temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1), 0); | |
3844 | temp = const_binop (BIT_AND_EXPR, temp, size_int (1), 0); | |
cf85c69b JW |
3845 | |
3846 | /* We must use a signed type in order to get an arithmetic right shift. | |
3847 | However, we must also avoid introducing accidental overflows, so that | |
b6cc0a72 | 3848 | a subsequent call to integer_zerop will work. Hence we must |
cf85c69b JW |
3849 | do the type conversion here. At this point, the constant is either |
3850 | zero or one, and the conversion to a signed type can never overflow. | |
3851 | We could get an overflow if this conversion is done anywhere else. */ | |
3852 | if (TREE_UNSIGNED (type)) | |
3853 | temp = convert (signed_type (type), temp); | |
3854 | ||
02103577 RK |
3855 | temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0); |
3856 | temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0); | |
d4453ee5 RK |
3857 | if (mask != 0) |
3858 | temp = const_binop (BIT_AND_EXPR, temp, convert (TREE_TYPE (c), mask), 0); | |
cf85c69b JW |
3859 | /* If necessary, convert the type back to match the type of C. */ |
3860 | if (TREE_UNSIGNED (type)) | |
3861 | temp = convert (type, temp); | |
d4453ee5 | 3862 | |
02103577 RK |
3863 | return convert (type, const_binop (BIT_XOR_EXPR, c, temp, 0)); |
3864 | } | |
3865 | \f | |
b2215d83 TW |
3866 | /* Find ways of folding logical expressions of LHS and RHS: |
3867 | Try to merge two comparisons to the same innermost item. | |
3868 | Look for range tests like "ch >= '0' && ch <= '9'". | |
3869 | Look for combinations of simple terms on machines with expensive branches | |
3870 | and evaluate the RHS unconditionally. | |
6d716ca8 RS |
3871 | |
3872 | For example, if we have p->a == 2 && p->b == 4 and we can make an | |
3873 | object large enough to span both A and B, we can do this with a comparison | |
3874 | against the object ANDed with the a mask. | |
3875 | ||
3876 | If we have p->a == q->a && p->b == q->b, we may be able to use bit masking | |
3877 | operations to do this with one comparison. | |
3878 | ||
3879 | We check for both normal comparisons and the BIT_AND_EXPRs made this by | |
3880 | function and the one above. | |
3881 | ||
3882 | CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR, | |
3883 | TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR. | |
3884 | ||
3885 | TRUTH_TYPE is the type of the logical operand and LHS and RHS are its | |
3886 | two operands. | |
3887 | ||
3888 | We return the simplified tree or 0 if no optimization is possible. */ | |
3889 | ||
3890 | static tree | |
b2215d83 | 3891 | fold_truthop (code, truth_type, lhs, rhs) |
6d716ca8 RS |
3892 | enum tree_code code; |
3893 | tree truth_type, lhs, rhs; | |
3894 | { | |
f42ef510 | 3895 | /* If this is the "or" of two comparisons, we can do something if |
6d716ca8 | 3896 | the comparisons are NE_EXPR. If this is the "and", we can do something |
b6cc0a72 | 3897 | if the comparisons are EQ_EXPR. I.e., |
6d716ca8 RS |
3898 | (a->b == 2 && a->c == 4) can become (a->new == NEW). |
3899 | ||
3900 | WANTED_CODE is this operation code. For single bit fields, we can | |
3901 | convert EQ_EXPR to NE_EXPR so we need not reject the "wrong" | |
3902 | comparison for one-bit fields. */ | |
3903 | ||
b2215d83 | 3904 | enum tree_code wanted_code; |
6d716ca8 | 3905 | enum tree_code lcode, rcode; |
b2215d83 | 3906 | tree ll_arg, lr_arg, rl_arg, rr_arg; |
6d716ca8 | 3907 | tree ll_inner, lr_inner, rl_inner, rr_inner; |
770ae6cc RK |
3908 | HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos; |
3909 | HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos; | |
3910 | HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos; | |
3911 | HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos; | |
6d716ca8 RS |
3912 | int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp; |
3913 | enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode; | |
3914 | enum machine_mode lnmode, rnmode; | |
3915 | tree ll_mask, lr_mask, rl_mask, rr_mask; | |
d4453ee5 | 3916 | tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask; |
b2215d83 | 3917 | tree l_const, r_const; |
bd910dcf | 3918 | tree lntype, rntype, result; |
6d716ca8 | 3919 | int first_bit, end_bit; |
b2215d83 | 3920 | int volatilep; |
6d716ca8 | 3921 | |
ebde8a27 RK |
3922 | /* Start by getting the comparison codes. Fail if anything is volatile. |
3923 | If one operand is a BIT_AND_EXPR with the constant one, treat it as if | |
3924 | it were surrounded with a NE_EXPR. */ | |
6d716ca8 | 3925 | |
ebde8a27 | 3926 | if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs)) |
b2215d83 TW |
3927 | return 0; |
3928 | ||
6d716ca8 RS |
3929 | lcode = TREE_CODE (lhs); |
3930 | rcode = TREE_CODE (rhs); | |
ef659ec0 | 3931 | |
96d4cf0a RK |
3932 | if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1))) |
3933 | lcode = NE_EXPR, lhs = build (NE_EXPR, truth_type, lhs, integer_zero_node); | |
3934 | ||
3935 | if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1))) | |
3936 | rcode = NE_EXPR, rhs = build (NE_EXPR, truth_type, rhs, integer_zero_node); | |
3937 | ||
ebde8a27 | 3938 | if (TREE_CODE_CLASS (lcode) != '<' || TREE_CODE_CLASS (rcode) != '<') |
ef659ec0 TW |
3939 | return 0; |
3940 | ||
b2215d83 | 3941 | code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR) |
9c0ae98b | 3942 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR); |
b2215d83 TW |
3943 | |
3944 | ll_arg = TREE_OPERAND (lhs, 0); | |
3945 | lr_arg = TREE_OPERAND (lhs, 1); | |
3946 | rl_arg = TREE_OPERAND (rhs, 0); | |
3947 | rr_arg = TREE_OPERAND (rhs, 1); | |
b6cc0a72 | 3948 | |
8227896c | 3949 | /* If the RHS can be evaluated unconditionally and its operands are |
b2215d83 TW |
3950 | simple, it wins to evaluate the RHS unconditionally on machines |
3951 | with expensive branches. In this case, this isn't a comparison | |
1d691c53 RK |
3952 | that can be merged. Avoid doing this if the RHS is a floating-point |
3953 | comparison since those can trap. */ | |
b2215d83 TW |
3954 | |
3955 | if (BRANCH_COST >= 2 | |
1d691c53 | 3956 | && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg)) |
b2215d83 | 3957 | && simple_operand_p (rl_arg) |
8227896c | 3958 | && simple_operand_p (rr_arg)) |
b2215d83 TW |
3959 | return build (code, truth_type, lhs, rhs); |
3960 | ||
ef659ec0 TW |
3961 | /* See if the comparisons can be merged. Then get all the parameters for |
3962 | each side. */ | |
3963 | ||
6d716ca8 | 3964 | if ((lcode != EQ_EXPR && lcode != NE_EXPR) |
ef659ec0 | 3965 | || (rcode != EQ_EXPR && rcode != NE_EXPR)) |
6d716ca8 RS |
3966 | return 0; |
3967 | ||
b2215d83 TW |
3968 | volatilep = 0; |
3969 | ll_inner = decode_field_reference (ll_arg, | |
6d716ca8 | 3970 | &ll_bitsize, &ll_bitpos, &ll_mode, |
d4453ee5 RK |
3971 | &ll_unsignedp, &volatilep, &ll_mask, |
3972 | &ll_and_mask); | |
b2215d83 | 3973 | lr_inner = decode_field_reference (lr_arg, |
6d716ca8 | 3974 | &lr_bitsize, &lr_bitpos, &lr_mode, |
d4453ee5 RK |
3975 | &lr_unsignedp, &volatilep, &lr_mask, |
3976 | &lr_and_mask); | |
b2215d83 | 3977 | rl_inner = decode_field_reference (rl_arg, |
6d716ca8 | 3978 | &rl_bitsize, &rl_bitpos, &rl_mode, |
d4453ee5 RK |
3979 | &rl_unsignedp, &volatilep, &rl_mask, |
3980 | &rl_and_mask); | |
b2215d83 | 3981 | rr_inner = decode_field_reference (rr_arg, |
6d716ca8 | 3982 | &rr_bitsize, &rr_bitpos, &rr_mode, |
d4453ee5 RK |
3983 | &rr_unsignedp, &volatilep, &rr_mask, |
3984 | &rr_and_mask); | |
6d716ca8 RS |
3985 | |
3986 | /* It must be true that the inner operation on the lhs of each | |
3987 | comparison must be the same if we are to be able to do anything. | |
3988 | Then see if we have constants. If not, the same must be true for | |
3989 | the rhs's. */ | |
3990 | if (volatilep || ll_inner == 0 || rl_inner == 0 | |
3991 | || ! operand_equal_p (ll_inner, rl_inner, 0)) | |
3992 | return 0; | |
3993 | ||
b2215d83 TW |
3994 | if (TREE_CODE (lr_arg) == INTEGER_CST |
3995 | && TREE_CODE (rr_arg) == INTEGER_CST) | |
3996 | l_const = lr_arg, r_const = rr_arg; | |
6d716ca8 RS |
3997 | else if (lr_inner == 0 || rr_inner == 0 |
3998 | || ! operand_equal_p (lr_inner, rr_inner, 0)) | |
3999 | return 0; | |
b2215d83 TW |
4000 | else |
4001 | l_const = r_const = 0; | |
6d716ca8 RS |
4002 | |
4003 | /* If either comparison code is not correct for our logical operation, | |
4004 | fail. However, we can convert a one-bit comparison against zero into | |
4005 | the opposite comparison against that bit being set in the field. */ | |
b2215d83 | 4006 | |
9c0ae98b | 4007 | wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR); |
6d716ca8 RS |
4008 | if (lcode != wanted_code) |
4009 | { | |
4010 | if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask)) | |
5a6b3365 | 4011 | { |
2bd21a02 AS |
4012 | /* Make the left operand unsigned, since we are only interested |
4013 | in the value of one bit. Otherwise we are doing the wrong | |
4014 | thing below. */ | |
4015 | ll_unsignedp = 1; | |
71a874cd | 4016 | l_const = ll_mask; |
5a6b3365 | 4017 | } |
6d716ca8 RS |
4018 | else |
4019 | return 0; | |
4020 | } | |
4021 | ||
71a874cd | 4022 | /* This is analogous to the code for l_const above. */ |
6d716ca8 RS |
4023 | if (rcode != wanted_code) |
4024 | { | |
4025 | if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask)) | |
5a6b3365 | 4026 | { |
2bd21a02 | 4027 | rl_unsignedp = 1; |
71a874cd | 4028 | r_const = rl_mask; |
5a6b3365 | 4029 | } |
6d716ca8 RS |
4030 | else |
4031 | return 0; | |
4032 | } | |
4033 | ||
4034 | /* See if we can find a mode that contains both fields being compared on | |
4035 | the left. If we can't, fail. Otherwise, update all constants and masks | |
4036 | to be relative to a field of that size. */ | |
4037 | first_bit = MIN (ll_bitpos, rl_bitpos); | |
4038 | end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize); | |
4039 | lnmode = get_best_mode (end_bit - first_bit, first_bit, | |
4040 | TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode, | |
4041 | volatilep); | |
4042 | if (lnmode == VOIDmode) | |
4043 | return 0; | |
4044 | ||
4045 | lnbitsize = GET_MODE_BITSIZE (lnmode); | |
4046 | lnbitpos = first_bit & ~ (lnbitsize - 1); | |
bd910dcf | 4047 | lntype = type_for_size (lnbitsize, 1); |
6d716ca8 RS |
4048 | xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos; |
4049 | ||
f76b9db2 ILT |
4050 | if (BYTES_BIG_ENDIAN) |
4051 | { | |
4052 | xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize; | |
4053 | xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize; | |
4054 | } | |
6d716ca8 | 4055 | |
bd910dcf | 4056 | ll_mask = const_binop (LSHIFT_EXPR, convert (lntype, ll_mask), |
91d33e36 | 4057 | size_int (xll_bitpos), 0); |
bd910dcf | 4058 | rl_mask = const_binop (LSHIFT_EXPR, convert (lntype, rl_mask), |
91d33e36 | 4059 | size_int (xrl_bitpos), 0); |
6d716ca8 | 4060 | |
6d716ca8 RS |
4061 | if (l_const) |
4062 | { | |
bd910dcf | 4063 | l_const = convert (lntype, l_const); |
b6cc0a72 | 4064 | l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask); |
02103577 RK |
4065 | l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos), 0); |
4066 | if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const, | |
4067 | fold (build1 (BIT_NOT_EXPR, | |
bd910dcf | 4068 | lntype, ll_mask)), |
02103577 RK |
4069 | 0))) |
4070 | { | |
ab87f8c8 | 4071 | warning ("comparison is always %d", wanted_code == NE_EXPR); |
b6cc0a72 | 4072 | |
02103577 RK |
4073 | return convert (truth_type, |
4074 | wanted_code == NE_EXPR | |
4075 | ? integer_one_node : integer_zero_node); | |
4076 | } | |
6d716ca8 RS |
4077 | } |
4078 | if (r_const) | |
4079 | { | |
bd910dcf | 4080 | r_const = convert (lntype, r_const); |
d4453ee5 | 4081 | r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask); |
02103577 RK |
4082 | r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos), 0); |
4083 | if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const, | |
4084 | fold (build1 (BIT_NOT_EXPR, | |
bd910dcf | 4085 | lntype, rl_mask)), |
02103577 RK |
4086 | 0))) |
4087 | { | |
ab87f8c8 JL |
4088 | warning ("comparison is always %d", wanted_code == NE_EXPR); |
4089 | ||
02103577 RK |
4090 | return convert (truth_type, |
4091 | wanted_code == NE_EXPR | |
4092 | ? integer_one_node : integer_zero_node); | |
4093 | } | |
6d716ca8 RS |
4094 | } |
4095 | ||
4096 | /* If the right sides are not constant, do the same for it. Also, | |
4097 | disallow this optimization if a size or signedness mismatch occurs | |
4098 | between the left and right sides. */ | |
4099 | if (l_const == 0) | |
4100 | { | |
4101 | if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize | |
e6a28f26 RS |
4102 | || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp |
4103 | /* Make sure the two fields on the right | |
4104 | correspond to the left without being swapped. */ | |
4105 | || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos) | |
6d716ca8 RS |
4106 | return 0; |
4107 | ||
4108 | first_bit = MIN (lr_bitpos, rr_bitpos); | |
4109 | end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize); | |
4110 | rnmode = get_best_mode (end_bit - first_bit, first_bit, | |
4111 | TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode, | |
4112 | volatilep); | |
4113 | if (rnmode == VOIDmode) | |
4114 | return 0; | |
4115 | ||
4116 | rnbitsize = GET_MODE_BITSIZE (rnmode); | |
4117 | rnbitpos = first_bit & ~ (rnbitsize - 1); | |
bd910dcf | 4118 | rntype = type_for_size (rnbitsize, 1); |
6d716ca8 RS |
4119 | xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos; |
4120 | ||
f76b9db2 ILT |
4121 | if (BYTES_BIG_ENDIAN) |
4122 | { | |
4123 | xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize; | |
4124 | xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize; | |
4125 | } | |
6d716ca8 | 4126 | |
bd910dcf | 4127 | lr_mask = const_binop (LSHIFT_EXPR, convert (rntype, lr_mask), |
91d33e36 | 4128 | size_int (xlr_bitpos), 0); |
bd910dcf | 4129 | rr_mask = const_binop (LSHIFT_EXPR, convert (rntype, rr_mask), |
91d33e36 | 4130 | size_int (xrr_bitpos), 0); |
6d716ca8 RS |
4131 | |
4132 | /* Make a mask that corresponds to both fields being compared. | |
11a86c56 CH |
4133 | Do this for both items being compared. If the operands are the |
4134 | same size and the bits being compared are in the same position | |
4135 | then we can do this by masking both and comparing the masked | |
4136 | results. */ | |
91d33e36 RS |
4137 | ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0); |
4138 | lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask, 0); | |
11a86c56 | 4139 | if (lnbitsize == rnbitsize && xll_bitpos == xlr_bitpos) |
6d716ca8 | 4140 | { |
bd910dcf | 4141 | lhs = make_bit_field_ref (ll_inner, lntype, lnbitsize, lnbitpos, |
6d716ca8 | 4142 | ll_unsignedp || rl_unsignedp); |
11a86c56 CH |
4143 | if (! all_ones_mask_p (ll_mask, lnbitsize)) |
4144 | lhs = build (BIT_AND_EXPR, lntype, lhs, ll_mask); | |
4145 | ||
bd910dcf | 4146 | rhs = make_bit_field_ref (lr_inner, rntype, rnbitsize, rnbitpos, |
6d716ca8 | 4147 | lr_unsignedp || rr_unsignedp); |
11a86c56 CH |
4148 | if (! all_ones_mask_p (lr_mask, rnbitsize)) |
4149 | rhs = build (BIT_AND_EXPR, rntype, rhs, lr_mask); | |
4150 | ||
6d716ca8 RS |
4151 | return build (wanted_code, truth_type, lhs, rhs); |
4152 | } | |
4153 | ||
4154 | /* There is still another way we can do something: If both pairs of | |
4155 | fields being compared are adjacent, we may be able to make a wider | |
97ea7176 CH |
4156 | field containing them both. |
4157 | ||
4158 | Note that we still must mask the lhs/rhs expressions. Furthermore, | |
b6cc0a72 | 4159 | the mask must be shifted to account for the shift done by |
97ea7176 | 4160 | make_bit_field_ref. */ |
6d716ca8 RS |
4161 | if ((ll_bitsize + ll_bitpos == rl_bitpos |
4162 | && lr_bitsize + lr_bitpos == rr_bitpos) | |
4163 | || (ll_bitpos == rl_bitpos + rl_bitsize | |
4164 | && lr_bitpos == rr_bitpos + rr_bitsize)) | |
97ea7176 | 4165 | { |
bd910dcf CH |
4166 | tree type; |
4167 | ||
4168 | lhs = make_bit_field_ref (ll_inner, lntype, ll_bitsize + rl_bitsize, | |
97ea7176 | 4169 | MIN (ll_bitpos, rl_bitpos), ll_unsignedp); |
bd910dcf CH |
4170 | rhs = make_bit_field_ref (lr_inner, rntype, lr_bitsize + rr_bitsize, |
4171 | MIN (lr_bitpos, rr_bitpos), lr_unsignedp); | |
4172 | ||
97ea7176 CH |
4173 | ll_mask = const_binop (RSHIFT_EXPR, ll_mask, |
4174 | size_int (MIN (xll_bitpos, xrl_bitpos)), 0); | |
bd910dcf CH |
4175 | lr_mask = const_binop (RSHIFT_EXPR, lr_mask, |
4176 | size_int (MIN (xlr_bitpos, xrr_bitpos)), 0); | |
4177 | ||
4178 | /* Convert to the smaller type before masking out unwanted bits. */ | |
4179 | type = lntype; | |
4180 | if (lntype != rntype) | |
4181 | { | |
4182 | if (lnbitsize > rnbitsize) | |
4183 | { | |
4184 | lhs = convert (rntype, lhs); | |
4185 | ll_mask = convert (rntype, ll_mask); | |
4186 | type = rntype; | |
4187 | } | |
4188 | else if (lnbitsize < rnbitsize) | |
4189 | { | |
4190 | rhs = convert (lntype, rhs); | |
4191 | lr_mask = convert (lntype, lr_mask); | |
4192 | type = lntype; | |
4193 | } | |
4194 | } | |
4195 | ||
97ea7176 CH |
4196 | if (! all_ones_mask_p (ll_mask, ll_bitsize + rl_bitsize)) |
4197 | lhs = build (BIT_AND_EXPR, type, lhs, ll_mask); | |
4198 | ||
97ea7176 CH |
4199 | if (! all_ones_mask_p (lr_mask, lr_bitsize + rr_bitsize)) |
4200 | rhs = build (BIT_AND_EXPR, type, rhs, lr_mask); | |
4201 | ||
4202 | return build (wanted_code, truth_type, lhs, rhs); | |
4203 | } | |
6d716ca8 RS |
4204 | |
4205 | return 0; | |
4206 | } | |
4207 | ||
4208 | /* Handle the case of comparisons with constants. If there is something in | |
4209 | common between the masks, those bits of the constants must be the same. | |
4210 | If not, the condition is always false. Test for this to avoid generating | |
4211 | incorrect code below. */ | |
91d33e36 | 4212 | result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask, 0); |
6d716ca8 | 4213 | if (! integer_zerop (result) |
91d33e36 RS |
4214 | && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const, 0), |
4215 | const_binop (BIT_AND_EXPR, result, r_const, 0)) != 1) | |
6d716ca8 RS |
4216 | { |
4217 | if (wanted_code == NE_EXPR) | |
4218 | { | |
4219 | warning ("`or' of unmatched not-equal tests is always 1"); | |
4220 | return convert (truth_type, integer_one_node); | |
4221 | } | |
4222 | else | |
4223 | { | |
ab87f8c8 | 4224 | warning ("`and' of mutually exclusive equal-tests is always 0"); |
6d716ca8 RS |
4225 | return convert (truth_type, integer_zero_node); |
4226 | } | |
4227 | } | |
4228 | ||
4229 | /* Construct the expression we will return. First get the component | |
4230 | reference we will make. Unless the mask is all ones the width of | |
4231 | that field, perform the mask operation. Then compare with the | |
4232 | merged constant. */ | |
bd910dcf | 4233 | result = make_bit_field_ref (ll_inner, lntype, lnbitsize, lnbitpos, |
6d716ca8 RS |
4234 | ll_unsignedp || rl_unsignedp); |
4235 | ||
91d33e36 | 4236 | ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0); |
6d716ca8 | 4237 | if (! all_ones_mask_p (ll_mask, lnbitsize)) |
bd910dcf | 4238 | result = build (BIT_AND_EXPR, lntype, result, ll_mask); |
6d716ca8 RS |
4239 | |
4240 | return build (wanted_code, truth_type, result, | |
91d33e36 | 4241 | const_binop (BIT_IOR_EXPR, l_const, r_const, 0)); |
6d716ca8 RS |
4242 | } |
4243 | \f | |
b6cc0a72 | 4244 | /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a |
14a774a9 RK |
4245 | constant. */ |
4246 | ||
4247 | static tree | |
4248 | optimize_minmax_comparison (t) | |
4249 | tree t; | |
4250 | { | |
4251 | tree type = TREE_TYPE (t); | |
4252 | tree arg0 = TREE_OPERAND (t, 0); | |
4253 | enum tree_code op_code; | |
4254 | tree comp_const = TREE_OPERAND (t, 1); | |
4255 | tree minmax_const; | |
4256 | int consts_equal, consts_lt; | |
4257 | tree inner; | |
4258 | ||
4259 | STRIP_SIGN_NOPS (arg0); | |
4260 | ||
4261 | op_code = TREE_CODE (arg0); | |
4262 | minmax_const = TREE_OPERAND (arg0, 1); | |
4263 | consts_equal = tree_int_cst_equal (minmax_const, comp_const); | |
4264 | consts_lt = tree_int_cst_lt (minmax_const, comp_const); | |
4265 | inner = TREE_OPERAND (arg0, 0); | |
4266 | ||
4267 | /* If something does not permit us to optimize, return the original tree. */ | |
4268 | if ((op_code != MIN_EXPR && op_code != MAX_EXPR) | |
4269 | || TREE_CODE (comp_const) != INTEGER_CST | |
4270 | || TREE_CONSTANT_OVERFLOW (comp_const) | |
4271 | || TREE_CODE (minmax_const) != INTEGER_CST | |
4272 | || TREE_CONSTANT_OVERFLOW (minmax_const)) | |
4273 | return t; | |
4274 | ||
4275 | /* Now handle all the various comparison codes. We only handle EQ_EXPR | |
4276 | and GT_EXPR, doing the rest with recursive calls using logical | |
4277 | simplifications. */ | |
4278 | switch (TREE_CODE (t)) | |
4279 | { | |
4280 | case NE_EXPR: case LT_EXPR: case LE_EXPR: | |
4281 | return | |
4282 | invert_truthvalue (optimize_minmax_comparison (invert_truthvalue (t))); | |
4283 | ||
4284 | case GE_EXPR: | |
4285 | return | |
4286 | fold (build (TRUTH_ORIF_EXPR, type, | |
4287 | optimize_minmax_comparison | |
4288 | (build (EQ_EXPR, type, arg0, comp_const)), | |
4289 | optimize_minmax_comparison | |
4290 | (build (GT_EXPR, type, arg0, comp_const)))); | |
4291 | ||
4292 | case EQ_EXPR: | |
4293 | if (op_code == MAX_EXPR && consts_equal) | |
4294 | /* MAX (X, 0) == 0 -> X <= 0 */ | |
4295 | return fold (build (LE_EXPR, type, inner, comp_const)); | |
4296 | ||
4297 | else if (op_code == MAX_EXPR && consts_lt) | |
4298 | /* MAX (X, 0) == 5 -> X == 5 */ | |
4299 | return fold (build (EQ_EXPR, type, inner, comp_const)); | |
4300 | ||
4301 | else if (op_code == MAX_EXPR) | |
4302 | /* MAX (X, 0) == -1 -> false */ | |
4303 | return omit_one_operand (type, integer_zero_node, inner); | |
4304 | ||
4305 | else if (consts_equal) | |
4306 | /* MIN (X, 0) == 0 -> X >= 0 */ | |
4307 | return fold (build (GE_EXPR, type, inner, comp_const)); | |
4308 | ||
4309 | else if (consts_lt) | |
4310 | /* MIN (X, 0) == 5 -> false */ | |
4311 | return omit_one_operand (type, integer_zero_node, inner); | |
4312 | ||
4313 | else | |
4314 | /* MIN (X, 0) == -1 -> X == -1 */ | |
4315 | return fold (build (EQ_EXPR, type, inner, comp_const)); | |
4316 | ||
4317 | case GT_EXPR: | |
4318 | if (op_code == MAX_EXPR && (consts_equal || consts_lt)) | |
4319 | /* MAX (X, 0) > 0 -> X > 0 | |
4320 | MAX (X, 0) > 5 -> X > 5 */ | |
4321 | return fold (build (GT_EXPR, type, inner, comp_const)); | |
4322 | ||
4323 | else if (op_code == MAX_EXPR) | |
4324 | /* MAX (X, 0) > -1 -> true */ | |
4325 | return omit_one_operand (type, integer_one_node, inner); | |
4326 | ||
4327 | else if (op_code == MIN_EXPR && (consts_equal || consts_lt)) | |
4328 | /* MIN (X, 0) > 0 -> false | |
4329 | MIN (X, 0) > 5 -> false */ | |
4330 | return omit_one_operand (type, integer_zero_node, inner); | |
4331 | ||
4332 | else | |
4333 | /* MIN (X, 0) > -1 -> X > -1 */ | |
4334 | return fold (build (GT_EXPR, type, inner, comp_const)); | |
4335 | ||
4336 | default: | |
4337 | return t; | |
4338 | } | |
4339 | } | |
4340 | \f | |
1baa375f RK |
4341 | /* T is an integer expression that is being multiplied, divided, or taken a |
4342 | modulus (CODE says which and what kind of divide or modulus) by a | |
4343 | constant C. See if we can eliminate that operation by folding it with | |
4344 | other operations already in T. WIDE_TYPE, if non-null, is a type that | |
4345 | should be used for the computation if wider than our type. | |
4346 | ||
4347 | For example, if we are dividing (X * 8) + (Y + 16) by 4, we can return | |
8e1ca098 RH |
4348 | (X * 2) + (Y + 4). We must, however, be assured that either the original |
4349 | expression would not overflow or that overflow is undefined for the type | |
4350 | in the language in question. | |
4351 | ||
4352 | We also canonicalize (X + 7) * 4 into X * 4 + 28 in the hope that either | |
4353 | the machine has a multiply-accumulate insn or that this is part of an | |
4354 | addressing calculation. | |
1baa375f RK |
4355 | |
4356 | If we return a non-null expression, it is an equivalent form of the | |
4357 | original computation, but need not be in the original type. */ | |
4358 | ||
4359 | static tree | |
4360 | extract_muldiv (t, c, code, wide_type) | |
4361 | tree t; | |
4362 | tree c; | |
4363 | enum tree_code code; | |
4364 | tree wide_type; | |
4365 | { | |
4366 | tree type = TREE_TYPE (t); | |
4367 | enum tree_code tcode = TREE_CODE (t); | |
b6cc0a72 | 4368 | tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type)) |
1baa375f RK |
4369 | > GET_MODE_SIZE (TYPE_MODE (type))) |
4370 | ? wide_type : type); | |
4371 | tree t1, t2; | |
4372 | int same_p = tcode == code; | |
9d0878fd | 4373 | tree op0 = NULL_TREE, op1 = NULL_TREE; |
1baa375f RK |
4374 | |
4375 | /* Don't deal with constants of zero here; they confuse the code below. */ | |
4376 | if (integer_zerop (c)) | |
8e1ca098 | 4377 | return NULL_TREE; |
1baa375f RK |
4378 | |
4379 | if (TREE_CODE_CLASS (tcode) == '1') | |
4380 | op0 = TREE_OPERAND (t, 0); | |
4381 | ||
4382 | if (TREE_CODE_CLASS (tcode) == '2') | |
4383 | op0 = TREE_OPERAND (t, 0), op1 = TREE_OPERAND (t, 1); | |
4384 | ||
4385 | /* Note that we need not handle conditional operations here since fold | |
4386 | already handles those cases. So just do arithmetic here. */ | |
4387 | switch (tcode) | |
4388 | { | |
4389 | case INTEGER_CST: | |
4390 | /* For a constant, we can always simplify if we are a multiply | |
4391 | or (for divide and modulus) if it is a multiple of our constant. */ | |
4392 | if (code == MULT_EXPR | |
4393 | || integer_zerop (const_binop (TRUNC_MOD_EXPR, t, c, 0))) | |
4394 | return const_binop (code, convert (ctype, t), convert (ctype, c), 0); | |
4395 | break; | |
4396 | ||
4397 | case CONVERT_EXPR: case NON_LVALUE_EXPR: case NOP_EXPR: | |
eff9c80d RH |
4398 | /* If op0 is an expression, and is unsigned, and the type is |
4399 | smaller than ctype, then we cannot widen the expression. */ | |
4400 | if ((TREE_CODE_CLASS (TREE_CODE (op0)) == '<' | |
4401 | || TREE_CODE_CLASS (TREE_CODE (op0)) == '1' | |
4402 | || TREE_CODE_CLASS (TREE_CODE (op0)) == '2' | |
4403 | || TREE_CODE_CLASS (TREE_CODE (op0)) == 'e') | |
4404 | && TREE_UNSIGNED (TREE_TYPE (op0)) | |
7393c642 RK |
4405 | && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE |
4406 | && TYPE_IS_SIZETYPE (TREE_TYPE (op0))) | |
eff9c80d RH |
4407 | && (GET_MODE_SIZE (TYPE_MODE (ctype)) |
4408 | > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0))))) | |
4409 | break; | |
4410 | ||
1baa375f | 4411 | /* Pass the constant down and see if we can make a simplification. If |
59adecfa RK |
4412 | we can, replace this expression with the inner simplification for |
4413 | possible later conversion to our or some other type. */ | |
1baa375f RK |
4414 | if (0 != (t1 = extract_muldiv (op0, convert (TREE_TYPE (op0), c), code, |
4415 | code == MULT_EXPR ? ctype : NULL_TREE))) | |
4416 | return t1; | |
4417 | break; | |
4418 | ||
4419 | case NEGATE_EXPR: case ABS_EXPR: | |
4420 | if ((t1 = extract_muldiv (op0, c, code, wide_type)) != 0) | |
4421 | return fold (build1 (tcode, ctype, convert (ctype, t1))); | |
4422 | break; | |
4423 | ||
4424 | case MIN_EXPR: case MAX_EXPR: | |
13393c8a JW |
4425 | /* If widening the type changes the signedness, then we can't perform |
4426 | this optimization as that changes the result. */ | |
eff9c80d | 4427 | if (TREE_UNSIGNED (ctype) != TREE_UNSIGNED (type)) |
13393c8a JW |
4428 | break; |
4429 | ||
1baa375f RK |
4430 | /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */ |
4431 | if ((t1 = extract_muldiv (op0, c, code, wide_type)) != 0 | |
4432 | && (t2 = extract_muldiv (op1, c, code, wide_type)) != 0) | |
59adecfa RK |
4433 | { |
4434 | if (tree_int_cst_sgn (c) < 0) | |
4435 | tcode = (tcode == MIN_EXPR ? MAX_EXPR : MIN_EXPR); | |
4436 | ||
4437 | return fold (build (tcode, ctype, convert (ctype, t1), | |
4438 | convert (ctype, t2))); | |
4439 | } | |
1baa375f RK |
4440 | break; |
4441 | ||
4442 | case WITH_RECORD_EXPR: | |
4443 | if ((t1 = extract_muldiv (TREE_OPERAND (t, 0), c, code, wide_type)) != 0) | |
4444 | return build (WITH_RECORD_EXPR, TREE_TYPE (t1), t1, | |
4445 | TREE_OPERAND (t, 1)); | |
4446 | break; | |
4447 | ||
4448 | case SAVE_EXPR: | |
59adecfa RK |
4449 | /* If this has not been evaluated and the operand has no side effects, |
4450 | we can see if we can do something inside it and make a new one. | |
4451 | Note that this test is overly conservative since we can do this | |
4452 | if the only reason it had side effects is that it was another | |
4453 | similar SAVE_EXPR, but that isn't worth bothering with. */ | |
4454 | if (SAVE_EXPR_RTL (t) == 0 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)) | |
1baa375f RK |
4455 | && 0 != (t1 = extract_muldiv (TREE_OPERAND (t, 0), c, code, |
4456 | wide_type))) | |
fe375cf1 JJ |
4457 | { |
4458 | t1 = save_expr (t1); | |
4459 | if (SAVE_EXPR_PERSISTENT_P (t) && TREE_CODE (t1) == SAVE_EXPR) | |
4460 | SAVE_EXPR_PERSISTENT_P (t1) = 1; | |
4461 | if (is_pending_size (t)) | |
4462 | put_pending_size (t1); | |
4463 | return t1; | |
4464 | } | |
1baa375f RK |
4465 | break; |
4466 | ||
4467 | case LSHIFT_EXPR: case RSHIFT_EXPR: | |
4468 | /* If the second operand is constant, this is a multiplication | |
4469 | or floor division, by a power of two, so we can treat it that | |
4470 | way unless the multiplier or divisor overflows. */ | |
4471 | if (TREE_CODE (op1) == INTEGER_CST | |
d08230fe NC |
4472 | /* const_binop may not detect overflow correctly, |
4473 | so check for it explicitly here. */ | |
4474 | && TYPE_PRECISION (TREE_TYPE (size_one_node)) > TREE_INT_CST_LOW (op1) | |
4475 | && TREE_INT_CST_HIGH (op1) == 0 | |
1baa375f RK |
4476 | && 0 != (t1 = convert (ctype, |
4477 | const_binop (LSHIFT_EXPR, size_one_node, | |
4478 | op1, 0))) | |
4479 | && ! TREE_OVERFLOW (t1)) | |
4480 | return extract_muldiv (build (tcode == LSHIFT_EXPR | |
4481 | ? MULT_EXPR : FLOOR_DIV_EXPR, | |
4482 | ctype, convert (ctype, op0), t1), | |
4483 | c, code, wide_type); | |
4484 | break; | |
4485 | ||
4486 | case PLUS_EXPR: case MINUS_EXPR: | |
4487 | /* See if we can eliminate the operation on both sides. If we can, we | |
4488 | can return a new PLUS or MINUS. If we can't, the only remaining | |
4489 | cases where we can do anything are if the second operand is a | |
4490 | constant. */ | |
4491 | t1 = extract_muldiv (op0, c, code, wide_type); | |
4492 | t2 = extract_muldiv (op1, c, code, wide_type); | |
fba2c0cd JJ |
4493 | if (t1 != 0 && t2 != 0 |
4494 | && (code == MULT_EXPR | |
4495 | /* If not multiplication, we can only do this if either operand | |
4496 | is divisible by c. */ | |
4497 | || multiple_of_p (ctype, op0, c) | |
4498 | || multiple_of_p (ctype, op1, c))) | |
1baa375f RK |
4499 | return fold (build (tcode, ctype, convert (ctype, t1), |
4500 | convert (ctype, t2))); | |
1baa375f | 4501 | |
59adecfa RK |
4502 | /* If this was a subtraction, negate OP1 and set it to be an addition. |
4503 | This simplifies the logic below. */ | |
4504 | if (tcode == MINUS_EXPR) | |
4505 | tcode = PLUS_EXPR, op1 = negate_expr (op1); | |
4506 | ||
f9011d04 RK |
4507 | if (TREE_CODE (op1) != INTEGER_CST) |
4508 | break; | |
4509 | ||
59adecfa RK |
4510 | /* If either OP1 or C are negative, this optimization is not safe for |
4511 | some of the division and remainder types while for others we need | |
4512 | to change the code. */ | |
4513 | if (tree_int_cst_sgn (op1) < 0 || tree_int_cst_sgn (c) < 0) | |
4514 | { | |
4515 | if (code == CEIL_DIV_EXPR) | |
4516 | code = FLOOR_DIV_EXPR; | |
4517 | else if (code == CEIL_MOD_EXPR) | |
4518 | code = FLOOR_MOD_EXPR; | |
4519 | else if (code == FLOOR_DIV_EXPR) | |
4520 | code = CEIL_DIV_EXPR; | |
4521 | else if (code == FLOOR_MOD_EXPR) | |
4522 | code = CEIL_MOD_EXPR; | |
4523 | else if (code != MULT_EXPR) | |
4524 | break; | |
4525 | } | |
4526 | ||
12644a9a TM |
4527 | /* If it's a multiply or a division/modulus operation of a multiple |
4528 | of our constant, do the operation and verify it doesn't overflow. */ | |
4529 | if (code == MULT_EXPR | |
4530 | || integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0))) | |
4531 | { | |
4532 | op1 = const_binop (code, convert (ctype, op1), convert (ctype, c), 0); | |
4533 | if (op1 == 0 || TREE_OVERFLOW (op1)) | |
4534 | break; | |
4535 | } | |
4536 | else | |
4537 | break; | |
59adecfa | 4538 | |
23cdce68 RH |
4539 | /* If we have an unsigned type is not a sizetype, we cannot widen |
4540 | the operation since it will change the result if the original | |
4541 | computation overflowed. */ | |
4542 | if (TREE_UNSIGNED (ctype) | |
7393c642 | 4543 | && ! (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)) |
23cdce68 RH |
4544 | && ctype != type) |
4545 | break; | |
4546 | ||
1baa375f | 4547 | /* If we were able to eliminate our operation from the first side, |
59adecfa RK |
4548 | apply our operation to the second side and reform the PLUS. */ |
4549 | if (t1 != 0 && (TREE_CODE (t1) != code || code == MULT_EXPR)) | |
4550 | return fold (build (tcode, ctype, convert (ctype, t1), op1)); | |
1baa375f RK |
4551 | |
4552 | /* The last case is if we are a multiply. In that case, we can | |
4553 | apply the distributive law to commute the multiply and addition | |
4554 | if the multiplication of the constants doesn't overflow. */ | |
59adecfa | 4555 | if (code == MULT_EXPR) |
1baa375f RK |
4556 | return fold (build (tcode, ctype, fold (build (code, ctype, |
4557 | convert (ctype, op0), | |
4558 | convert (ctype, c))), | |
59adecfa | 4559 | op1)); |
1baa375f RK |
4560 | |
4561 | break; | |
4562 | ||
4563 | case MULT_EXPR: | |
4564 | /* We have a special case here if we are doing something like | |
4565 | (C * 8) % 4 since we know that's zero. */ | |
4566 | if ((code == TRUNC_MOD_EXPR || code == CEIL_MOD_EXPR | |
4567 | || code == FLOOR_MOD_EXPR || code == ROUND_MOD_EXPR) | |
4568 | && TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST | |
4569 | && integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0))) | |
4570 | return omit_one_operand (type, integer_zero_node, op0); | |
4571 | ||
4572 | /* ... fall through ... */ | |
4573 | ||
4574 | case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR: | |
4575 | case ROUND_DIV_EXPR: case EXACT_DIV_EXPR: | |
4576 | /* If we can extract our operation from the LHS, do so and return a | |
4577 | new operation. Likewise for the RHS from a MULT_EXPR. Otherwise, | |
4578 | do something only if the second operand is a constant. */ | |
4579 | if (same_p | |
4580 | && (t1 = extract_muldiv (op0, c, code, wide_type)) != 0) | |
4581 | return fold (build (tcode, ctype, convert (ctype, t1), | |
4582 | convert (ctype, op1))); | |
4583 | else if (tcode == MULT_EXPR && code == MULT_EXPR | |
4584 | && (t1 = extract_muldiv (op1, c, code, wide_type)) != 0) | |
4585 | return fold (build (tcode, ctype, convert (ctype, op0), | |
4586 | convert (ctype, t1))); | |
4587 | else if (TREE_CODE (op1) != INTEGER_CST) | |
4588 | return 0; | |
4589 | ||
4590 | /* If these are the same operation types, we can associate them | |
4591 | assuming no overflow. */ | |
4592 | if (tcode == code | |
4593 | && 0 != (t1 = const_binop (MULT_EXPR, convert (ctype, op1), | |
4594 | convert (ctype, c), 0)) | |
4595 | && ! TREE_OVERFLOW (t1)) | |
4596 | return fold (build (tcode, ctype, convert (ctype, op0), t1)); | |
4597 | ||
4598 | /* If these operations "cancel" each other, we have the main | |
4599 | optimizations of this pass, which occur when either constant is a | |
4600 | multiple of the other, in which case we replace this with either an | |
b6cc0a72 | 4601 | operation or CODE or TCODE. |
8e1ca098 RH |
4602 | |
4603 | If we have an unsigned type that is not a sizetype, we canot do | |
4604 | this since it will change the result if the original computation | |
4605 | overflowed. */ | |
4606 | if ((! TREE_UNSIGNED (ctype) | |
7393c642 | 4607 | || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype))) |
8e1ca098 RH |
4608 | && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR) |
4609 | || (tcode == MULT_EXPR | |
4610 | && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR | |
4611 | && code != FLOOR_MOD_EXPR && code != ROUND_MOD_EXPR))) | |
1baa375f RK |
4612 | { |
4613 | if (integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0))) | |
4614 | return fold (build (tcode, ctype, convert (ctype, op0), | |
4615 | convert (ctype, | |
4616 | const_binop (TRUNC_DIV_EXPR, | |
4617 | op1, c, 0)))); | |
4618 | else if (integer_zerop (const_binop (TRUNC_MOD_EXPR, c, op1, 0))) | |
4619 | return fold (build (code, ctype, convert (ctype, op0), | |
4620 | convert (ctype, | |
4621 | const_binop (TRUNC_DIV_EXPR, | |
4622 | c, op1, 0)))); | |
4623 | } | |
4624 | break; | |
4625 | ||
4626 | default: | |
4627 | break; | |
4628 | } | |
4629 | ||
4630 | return 0; | |
4631 | } | |
4632 | \f | |
b5f3b6b6 RK |
4633 | /* If T contains a COMPOUND_EXPR which was inserted merely to evaluate |
4634 | S, a SAVE_EXPR, return the expression actually being evaluated. Note | |
4635 | that we may sometimes modify the tree. */ | |
4636 | ||
4637 | static tree | |
4638 | strip_compound_expr (t, s) | |
4639 | tree t; | |
4640 | tree s; | |
4641 | { | |
b5f3b6b6 RK |
4642 | enum tree_code code = TREE_CODE (t); |
4643 | ||
4644 | /* See if this is the COMPOUND_EXPR we want to eliminate. */ | |
4645 | if (code == COMPOUND_EXPR && TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR | |
4646 | && TREE_OPERAND (TREE_OPERAND (t, 0), 0) == s) | |
4647 | return TREE_OPERAND (t, 1); | |
4648 | ||
4649 | /* See if this is a COND_EXPR or a simple arithmetic operator. We | |
4650 | don't bother handling any other types. */ | |
4651 | else if (code == COND_EXPR) | |
4652 | { | |
4653 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
4654 | TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s); | |
4655 | TREE_OPERAND (t, 2) = strip_compound_expr (TREE_OPERAND (t, 2), s); | |
4656 | } | |
4657 | else if (TREE_CODE_CLASS (code) == '1') | |
4658 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
4659 | else if (TREE_CODE_CLASS (code) == '<' | |
4660 | || TREE_CODE_CLASS (code) == '2') | |
4661 | { | |
4662 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
4663 | TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s); | |
4664 | } | |
4665 | ||
4666 | return t; | |
4667 | } | |
4668 | \f | |
f628873f MM |
4669 | /* Return a node which has the indicated constant VALUE (either 0 or |
4670 | 1), and is of the indicated TYPE. */ | |
4671 | ||
83e0821b | 4672 | static tree |
f628873f MM |
4673 | constant_boolean_node (value, type) |
4674 | int value; | |
4675 | tree type; | |
4676 | { | |
4677 | if (type == integer_type_node) | |
4678 | return value ? integer_one_node : integer_zero_node; | |
4679 | else if (TREE_CODE (type) == BOOLEAN_TYPE) | |
4680 | return truthvalue_conversion (value ? integer_one_node : | |
b6cc0a72 KH |
4681 | integer_zero_node); |
4682 | else | |
f628873f MM |
4683 | { |
4684 | tree t = build_int_2 (value, 0); | |
d4b60170 | 4685 | |
f628873f MM |
4686 | TREE_TYPE (t) = type; |
4687 | return t; | |
4688 | } | |
4689 | } | |
4690 | ||
ab87f8c8 JL |
4691 | /* Utility function for the following routine, to see how complex a nesting of |
4692 | COND_EXPRs can be. EXPR is the expression and LIMIT is a count beyond which | |
4693 | we don't care (to avoid spending too much time on complex expressions.). */ | |
4694 | ||
4695 | static int | |
4696 | count_cond (expr, lim) | |
4697 | tree expr; | |
4698 | int lim; | |
4699 | { | |
d6edb99e | 4700 | int ctrue, cfalse; |
ab87f8c8 JL |
4701 | |
4702 | if (TREE_CODE (expr) != COND_EXPR) | |
4703 | return 0; | |
4704 | else if (lim <= 0) | |
4705 | return 0; | |
4706 | ||
d6edb99e ZW |
4707 | ctrue = count_cond (TREE_OPERAND (expr, 1), lim - 1); |
4708 | cfalse = count_cond (TREE_OPERAND (expr, 2), lim - 1 - ctrue); | |
4709 | return MIN (lim, 1 + ctrue + cfalse); | |
ab87f8c8 | 4710 | } |
68626d4f MM |
4711 | |
4712 | /* Transform `a + (b ? x : y)' into `x ? (a + b) : (a + y)'. | |
4713 | Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here | |
4714 | CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)' | |
4715 | expression, and ARG to `a'. If COND_FIRST_P is non-zero, then the | |
4716 | COND is the first argument to CODE; otherwise (as in the example | |
4717 | given here), it is the second argument. TYPE is the type of the | |
4718 | original expression. */ | |
4719 | ||
4720 | static tree | |
4721 | fold_binary_op_with_conditional_arg (code, type, cond, arg, cond_first_p) | |
4722 | enum tree_code code; | |
4723 | tree type; | |
4724 | tree cond; | |
4725 | tree arg; | |
4726 | int cond_first_p; | |
4727 | { | |
4728 | tree test, true_value, false_value; | |
4729 | tree lhs = NULL_TREE; | |
4730 | tree rhs = NULL_TREE; | |
4731 | /* In the end, we'll produce a COND_EXPR. Both arms of the | |
4732 | conditional expression will be binary operations. The left-hand | |
4733 | side of the expression to be executed if the condition is true | |
4734 | will be pointed to by TRUE_LHS. Similarly, the right-hand side | |
4735 | of the expression to be executed if the condition is true will be | |
4736 | pointed to by TRUE_RHS. FALSE_LHS and FALSE_RHS are analagous -- | |
4737 | but apply to the expression to be executed if the conditional is | |
4738 | false. */ | |
4739 | tree *true_lhs; | |
4740 | tree *true_rhs; | |
4741 | tree *false_lhs; | |
4742 | tree *false_rhs; | |
4743 | /* These are the codes to use for the left-hand side and right-hand | |
4744 | side of the COND_EXPR. Normally, they are the same as CODE. */ | |
4745 | enum tree_code lhs_code = code; | |
4746 | enum tree_code rhs_code = code; | |
4747 | /* And these are the types of the expressions. */ | |
4748 | tree lhs_type = type; | |
4749 | tree rhs_type = type; | |
4750 | ||
4751 | if (cond_first_p) | |
4752 | { | |
4753 | true_rhs = false_rhs = &arg; | |
4754 | true_lhs = &true_value; | |
4755 | false_lhs = &false_value; | |
4756 | } | |
4757 | else | |
4758 | { | |
4759 | true_lhs = false_lhs = &arg; | |
4760 | true_rhs = &true_value; | |
4761 | false_rhs = &false_value; | |
4762 | } | |
4763 | ||
4764 | if (TREE_CODE (cond) == COND_EXPR) | |
4765 | { | |
4766 | test = TREE_OPERAND (cond, 0); | |
4767 | true_value = TREE_OPERAND (cond, 1); | |
4768 | false_value = TREE_OPERAND (cond, 2); | |
4769 | /* If this operand throws an expression, then it does not make | |
4770 | sense to try to perform a logical or arithmetic operation | |
4771 | involving it. Instead of building `a + throw 3' for example, | |
4772 | we simply build `a, throw 3'. */ | |
4773 | if (VOID_TYPE_P (TREE_TYPE (true_value))) | |
4774 | { | |
4775 | lhs_code = COMPOUND_EXPR; | |
4776 | if (!cond_first_p) | |
4777 | lhs_type = void_type_node; | |
4778 | } | |
4779 | if (VOID_TYPE_P (TREE_TYPE (false_value))) | |
4780 | { | |
4781 | rhs_code = COMPOUND_EXPR; | |
4782 | if (!cond_first_p) | |
4783 | rhs_type = void_type_node; | |
4784 | } | |
4785 | } | |
4786 | else | |
4787 | { | |
4788 | tree testtype = TREE_TYPE (cond); | |
4789 | test = cond; | |
4790 | true_value = convert (testtype, integer_one_node); | |
4791 | false_value = convert (testtype, integer_zero_node); | |
4792 | } | |
4793 | ||
4794 | /* If ARG is complex we want to make sure we only evaluate | |
4795 | it once. Though this is only required if it is volatile, it | |
4796 | might be more efficient even if it is not. However, if we | |
4797 | succeed in folding one part to a constant, we do not need | |
4798 | to make this SAVE_EXPR. Since we do this optimization | |
4799 | primarily to see if we do end up with constant and this | |
4800 | SAVE_EXPR interferes with later optimizations, suppressing | |
4801 | it when we can is important. | |
4802 | ||
4803 | If we are not in a function, we can't make a SAVE_EXPR, so don't | |
4804 | try to do so. Don't try to see if the result is a constant | |
4805 | if an arm is a COND_EXPR since we get exponential behavior | |
4806 | in that case. */ | |
4807 | ||
4808 | if (TREE_CODE (arg) != SAVE_EXPR && ! TREE_CONSTANT (arg) | |
4809 | && global_bindings_p () == 0 | |
4810 | && ((TREE_CODE (arg) != VAR_DECL | |
4811 | && TREE_CODE (arg) != PARM_DECL) | |
4812 | || TREE_SIDE_EFFECTS (arg))) | |
4813 | { | |
4814 | if (TREE_CODE (true_value) != COND_EXPR) | |
4815 | lhs = fold (build (lhs_code, lhs_type, *true_lhs, *true_rhs)); | |
4816 | ||
4817 | if (TREE_CODE (false_value) != COND_EXPR) | |
4818 | rhs = fold (build (rhs_code, rhs_type, *false_lhs, *false_rhs)); | |
4819 | ||
4820 | if ((lhs == 0 || ! TREE_CONSTANT (lhs)) | |
4821 | && (rhs == 0 || !TREE_CONSTANT (rhs))) | |
4822 | arg = save_expr (arg), lhs = rhs = 0; | |
4823 | } | |
4824 | ||
4825 | if (lhs == 0) | |
4826 | lhs = fold (build (lhs_code, lhs_type, *true_lhs, *true_rhs)); | |
4827 | if (rhs == 0) | |
4828 | rhs = fold (build (rhs_code, rhs_type, *false_lhs, *false_rhs)); | |
4829 | ||
4830 | test = fold (build (COND_EXPR, type, test, lhs, rhs)); | |
4831 | ||
4832 | if (TREE_CODE (arg) == SAVE_EXPR) | |
4833 | return build (COMPOUND_EXPR, type, | |
4834 | convert (void_type_node, arg), | |
4835 | strip_compound_expr (test, arg)); | |
4836 | else | |
4837 | return convert (type, test); | |
4838 | } | |
4839 | ||
ab87f8c8 | 4840 | \f |
6d716ca8 RS |
4841 | /* Perform constant folding and related simplification of EXPR. |
4842 | The related simplifications include x*1 => x, x*0 => 0, etc., | |
4843 | and application of the associative law. | |
4844 | NOP_EXPR conversions may be removed freely (as long as we | |
4845 | are careful not to change the C type of the overall expression) | |
4846 | We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR, | |
4847 | but we can constant-fold them if they have constant operands. */ | |
4848 | ||
4849 | tree | |
b6cc0a72 | 4850 | fold (expr) |
6d716ca8 RS |
4851 | tree expr; |
4852 | { | |
4853 | register tree t = expr; | |
4854 | tree t1 = NULL_TREE; | |
c05a9b68 | 4855 | tree tem; |
6d716ca8 | 4856 | tree type = TREE_TYPE (expr); |
4e86caed | 4857 | register tree arg0 = NULL_TREE, arg1 = NULL_TREE; |
6d716ca8 | 4858 | register enum tree_code code = TREE_CODE (t); |
1796dff4 | 4859 | register int kind = TREE_CODE_CLASS (code); |
c05a9b68 | 4860 | int invert; |
6d716ca8 RS |
4861 | /* WINS will be nonzero when the switch is done |
4862 | if all operands are constant. */ | |
6d716ca8 RS |
4863 | int wins = 1; |
4864 | ||
b6cc0a72 | 4865 | /* Don't try to process an RTL_EXPR since its operands aren't trees. |
5fd7f37d | 4866 | Likewise for a SAVE_EXPR that's already been evaluated. */ |
dea8be3e | 4867 | if (code == RTL_EXPR || (code == SAVE_EXPR && SAVE_EXPR_RTL (t) != 0)) |
ac27d589 RK |
4868 | return t; |
4869 | ||
1796dff4 RH |
4870 | /* Return right away if a constant. */ |
4871 | if (kind == 'c') | |
4872 | return t; | |
b6cc0a72 | 4873 | |
dbecbbe4 JL |
4874 | #ifdef MAX_INTEGER_COMPUTATION_MODE |
4875 | check_max_integer_computation_mode (expr); | |
4876 | #endif | |
4877 | ||
1b81aa14 RS |
4878 | if (code == NOP_EXPR || code == FLOAT_EXPR || code == CONVERT_EXPR) |
4879 | { | |
1cc1b11a RS |
4880 | tree subop; |
4881 | ||
1b81aa14 RS |
4882 | /* Special case for conversion ops that can have fixed point args. */ |
4883 | arg0 = TREE_OPERAND (t, 0); | |
4884 | ||
4885 | /* Don't use STRIP_NOPS, because signedness of argument type matters. */ | |
4886 | if (arg0 != 0) | |
14a774a9 | 4887 | STRIP_SIGN_NOPS (arg0); |
1b81aa14 | 4888 | |
1cc1b11a RS |
4889 | if (arg0 != 0 && TREE_CODE (arg0) == COMPLEX_CST) |
4890 | subop = TREE_REALPART (arg0); | |
4891 | else | |
4892 | subop = arg0; | |
4893 | ||
4894 | if (subop != 0 && TREE_CODE (subop) != INTEGER_CST | |
1b81aa14 | 4895 | #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) |
1cc1b11a | 4896 | && TREE_CODE (subop) != REAL_CST |
1b81aa14 RS |
4897 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ |
4898 | ) | |
4899 | /* Note that TREE_CONSTANT isn't enough: | |
4900 | static var addresses are constant but we can't | |
4901 | do arithmetic on them. */ | |
4902 | wins = 0; | |
4903 | } | |
efd58783 | 4904 | else if (IS_EXPR_CODE_CLASS (kind) || kind == 'r') |
6d716ca8 | 4905 | { |
dea8be3e | 4906 | register int len = first_rtl_op (code); |
6d716ca8 RS |
4907 | register int i; |
4908 | for (i = 0; i < len; i++) | |
4909 | { | |
4910 | tree op = TREE_OPERAND (t, i); | |
1cc1b11a | 4911 | tree subop; |
6d716ca8 RS |
4912 | |
4913 | if (op == 0) | |
4914 | continue; /* Valid for CALL_EXPR, at least. */ | |
4915 | ||
b8a91430 RK |
4916 | if (kind == '<' || code == RSHIFT_EXPR) |
4917 | { | |
4918 | /* Signedness matters here. Perhaps we can refine this | |
4919 | later. */ | |
14a774a9 | 4920 | STRIP_SIGN_NOPS (op); |
b8a91430 RK |
4921 | } |
4922 | else | |
13eb1f7f RK |
4923 | /* Strip any conversions that don't change the mode. */ |
4924 | STRIP_NOPS (op); | |
b6cc0a72 | 4925 | |
1cc1b11a RS |
4926 | if (TREE_CODE (op) == COMPLEX_CST) |
4927 | subop = TREE_REALPART (op); | |
4928 | else | |
4929 | subop = op; | |
4930 | ||
4931 | if (TREE_CODE (subop) != INTEGER_CST | |
6d716ca8 | 4932 | #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) |
1cc1b11a | 4933 | && TREE_CODE (subop) != REAL_CST |
6d716ca8 RS |
4934 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ |
4935 | ) | |
4936 | /* Note that TREE_CONSTANT isn't enough: | |
4937 | static var addresses are constant but we can't | |
4938 | do arithmetic on them. */ | |
4939 | wins = 0; | |
4940 | ||
4941 | if (i == 0) | |
4942 | arg0 = op; | |
4943 | else if (i == 1) | |
4944 | arg1 = op; | |
4945 | } | |
4946 | } | |
4947 | ||
4948 | /* If this is a commutative operation, and ARG0 is a constant, move it | |
4949 | to ARG1 to reduce the number of tests below. */ | |
4950 | if ((code == PLUS_EXPR || code == MULT_EXPR || code == MIN_EXPR | |
4951 | || code == MAX_EXPR || code == BIT_IOR_EXPR || code == BIT_XOR_EXPR | |
4952 | || code == BIT_AND_EXPR) | |
4953 | && (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)) | |
4954 | { | |
c05a9b68 | 4955 | tem = arg0; arg0 = arg1; arg1 = tem; |
6d716ca8 | 4956 | |
c05a9b68 RS |
4957 | tem = TREE_OPERAND (t, 0); TREE_OPERAND (t, 0) = TREE_OPERAND (t, 1); |
4958 | TREE_OPERAND (t, 1) = tem; | |
6d716ca8 RS |
4959 | } |
4960 | ||
4961 | /* Now WINS is set as described above, | |
4962 | ARG0 is the first operand of EXPR, | |
4963 | and ARG1 is the second operand (if it has more than one operand). | |
4964 | ||
4965 | First check for cases where an arithmetic operation is applied to a | |
4966 | compound, conditional, or comparison operation. Push the arithmetic | |
4967 | operation inside the compound or conditional to see if any folding | |
4968 | can then be done. Convert comparison to conditional for this purpose. | |
4969 | The also optimizes non-constant cases that used to be done in | |
96d4cf0a RK |
4970 | expand_expr. |
4971 | ||
fba5638f | 4972 | Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR, |
61f275ff RK |
4973 | one of the operands is a comparison and the other is a comparison, a |
4974 | BIT_AND_EXPR with the constant 1, or a truth value. In that case, the | |
4975 | code below would make the expression more complex. Change it to a | |
b6cc0a72 | 4976 | TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to |
2df46b06 | 4977 | TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */ |
96d4cf0a | 4978 | |
2df46b06 RK |
4979 | if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR |
4980 | || code == EQ_EXPR || code == NE_EXPR) | |
61f275ff RK |
4981 | && ((truth_value_p (TREE_CODE (arg0)) |
4982 | && (truth_value_p (TREE_CODE (arg1)) | |
96d4cf0a RK |
4983 | || (TREE_CODE (arg1) == BIT_AND_EXPR |
4984 | && integer_onep (TREE_OPERAND (arg1, 1))))) | |
61f275ff RK |
4985 | || (truth_value_p (TREE_CODE (arg1)) |
4986 | && (truth_value_p (TREE_CODE (arg0)) | |
96d4cf0a RK |
4987 | || (TREE_CODE (arg0) == BIT_AND_EXPR |
4988 | && integer_onep (TREE_OPERAND (arg0, 1))))))) | |
2df46b06 RK |
4989 | { |
4990 | t = fold (build (code == BIT_AND_EXPR ? TRUTH_AND_EXPR | |
4991 | : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR | |
4992 | : TRUTH_XOR_EXPR, | |
4993 | type, arg0, arg1)); | |
4994 | ||
4995 | if (code == EQ_EXPR) | |
4996 | t = invert_truthvalue (t); | |
4997 | ||
4998 | return t; | |
4999 | } | |
96d4cf0a | 5000 | |
6d716ca8 RS |
5001 | if (TREE_CODE_CLASS (code) == '1') |
5002 | { | |
5003 | if (TREE_CODE (arg0) == COMPOUND_EXPR) | |
5004 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
5005 | fold (build1 (code, type, TREE_OPERAND (arg0, 1)))); | |
5006 | else if (TREE_CODE (arg0) == COND_EXPR) | |
b8eb43a2 RK |
5007 | { |
5008 | t = fold (build (COND_EXPR, type, TREE_OPERAND (arg0, 0), | |
5009 | fold (build1 (code, type, TREE_OPERAND (arg0, 1))), | |
5010 | fold (build1 (code, type, TREE_OPERAND (arg0, 2))))); | |
5011 | ||
5012 | /* If this was a conversion, and all we did was to move into | |
e1f56f62 RK |
5013 | inside the COND_EXPR, bring it back out. But leave it if |
5014 | it is a conversion from integer to integer and the | |
5015 | result precision is no wider than a word since such a | |
5016 | conversion is cheap and may be optimized away by combine, | |
5017 | while it couldn't if it were outside the COND_EXPR. Then return | |
5018 | so we don't get into an infinite recursion loop taking the | |
5019 | conversion out and then back in. */ | |
b8eb43a2 RK |
5020 | |
5021 | if ((code == NOP_EXPR || code == CONVERT_EXPR | |
5022 | || code == NON_LVALUE_EXPR) | |
5023 | && TREE_CODE (t) == COND_EXPR | |
5024 | && TREE_CODE (TREE_OPERAND (t, 1)) == code | |
459a2653 RK |
5025 | && TREE_CODE (TREE_OPERAND (t, 2)) == code |
5026 | && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)) | |
e1f56f62 RK |
5027 | == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 2), 0))) |
5028 | && ! (INTEGRAL_TYPE_P (TREE_TYPE (t)) | |
d4b60170 RK |
5029 | && (INTEGRAL_TYPE_P |
5030 | (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)))) | |
e1f56f62 | 5031 | && TYPE_PRECISION (TREE_TYPE (t)) <= BITS_PER_WORD)) |
b8eb43a2 RK |
5032 | t = build1 (code, type, |
5033 | build (COND_EXPR, | |
d4b60170 RK |
5034 | TREE_TYPE (TREE_OPERAND |
5035 | (TREE_OPERAND (t, 1), 0)), | |
b8eb43a2 RK |
5036 | TREE_OPERAND (t, 0), |
5037 | TREE_OPERAND (TREE_OPERAND (t, 1), 0), | |
5038 | TREE_OPERAND (TREE_OPERAND (t, 2), 0))); | |
5039 | return t; | |
5040 | } | |
b6cc0a72 | 5041 | else if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<') |
6d716ca8 RS |
5042 | return fold (build (COND_EXPR, type, arg0, |
5043 | fold (build1 (code, type, integer_one_node)), | |
5044 | fold (build1 (code, type, integer_zero_node)))); | |
5045 | } | |
96d4cf0a RK |
5046 | else if (TREE_CODE_CLASS (code) == '2' |
5047 | || TREE_CODE_CLASS (code) == '<') | |
6d716ca8 RS |
5048 | { |
5049 | if (TREE_CODE (arg1) == COMPOUND_EXPR) | |
5050 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), | |
96d4cf0a RK |
5051 | fold (build (code, type, |
5052 | arg0, TREE_OPERAND (arg1, 1)))); | |
f0eebf28 RK |
5053 | else if ((TREE_CODE (arg1) == COND_EXPR |
5054 | || (TREE_CODE_CLASS (TREE_CODE (arg1)) == '<' | |
5055 | && TREE_CODE_CLASS (code) != '<')) | |
ab87f8c8 JL |
5056 | && (TREE_CODE (arg0) != COND_EXPR |
5057 | || count_cond (arg0, 25) + count_cond (arg1, 25) <= 25) | |
9ec36da5 | 5058 | && (! TREE_SIDE_EFFECTS (arg0) |
c5c76735 | 5059 | || (global_bindings_p () == 0 |
9ec36da5 | 5060 | && ! contains_placeholder_p (arg0)))) |
68626d4f MM |
5061 | return |
5062 | fold_binary_op_with_conditional_arg (code, type, arg1, arg0, | |
5063 | /*cond_first_p=*/0); | |
6d716ca8 RS |
5064 | else if (TREE_CODE (arg0) == COMPOUND_EXPR) |
5065 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
5066 | fold (build (code, type, TREE_OPERAND (arg0, 1), arg1))); | |
f0eebf28 RK |
5067 | else if ((TREE_CODE (arg0) == COND_EXPR |
5068 | || (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' | |
5069 | && TREE_CODE_CLASS (code) != '<')) | |
ab87f8c8 JL |
5070 | && (TREE_CODE (arg1) != COND_EXPR |
5071 | || count_cond (arg0, 25) + count_cond (arg1, 25) <= 25) | |
9ec36da5 | 5072 | && (! TREE_SIDE_EFFECTS (arg1) |
c5c76735 | 5073 | || (global_bindings_p () == 0 |
9ec36da5 | 5074 | && ! contains_placeholder_p (arg1)))) |
68626d4f MM |
5075 | return |
5076 | fold_binary_op_with_conditional_arg (code, type, arg0, arg1, | |
5077 | /*cond_first_p=*/1); | |
6d716ca8 | 5078 | } |
c05a9b68 RS |
5079 | else if (TREE_CODE_CLASS (code) == '<' |
5080 | && TREE_CODE (arg0) == COMPOUND_EXPR) | |
5081 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
5082 | fold (build (code, type, TREE_OPERAND (arg0, 1), arg1))); | |
5083 | else if (TREE_CODE_CLASS (code) == '<' | |
5084 | && TREE_CODE (arg1) == COMPOUND_EXPR) | |
5085 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), | |
5086 | fold (build (code, type, arg0, TREE_OPERAND (arg1, 1)))); | |
b6cc0a72 | 5087 | |
6d716ca8 RS |
5088 | switch (code) |
5089 | { | |
5090 | case INTEGER_CST: | |
5091 | case REAL_CST: | |
5092 | case STRING_CST: | |
5093 | case COMPLEX_CST: | |
5094 | case CONSTRUCTOR: | |
5095 | return t; | |
5096 | ||
5097 | case CONST_DECL: | |
5098 | return fold (DECL_INITIAL (t)); | |
5099 | ||
5100 | case NOP_EXPR: | |
5101 | case FLOAT_EXPR: | |
5102 | case CONVERT_EXPR: | |
5103 | case FIX_TRUNC_EXPR: | |
5104 | /* Other kinds of FIX are not handled properly by fold_convert. */ | |
33558beb | 5105 | |
e1f56f62 RK |
5106 | if (TREE_TYPE (TREE_OPERAND (t, 0)) == TREE_TYPE (t)) |
5107 | return TREE_OPERAND (t, 0); | |
5108 | ||
7e139075 RK |
5109 | /* Handle cases of two conversions in a row. */ |
5110 | if (TREE_CODE (TREE_OPERAND (t, 0)) == NOP_EXPR | |
5111 | || TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR) | |
5112 | { | |
5113 | tree inside_type = TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
5114 | tree inter_type = TREE_TYPE (TREE_OPERAND (t, 0)); | |
5115 | tree final_type = TREE_TYPE (t); | |
5116 | int inside_int = INTEGRAL_TYPE_P (inside_type); | |
7f0b305c | 5117 | int inside_ptr = POINTER_TYPE_P (inside_type); |
7e139075 | 5118 | int inside_float = FLOAT_TYPE_P (inside_type); |
770ae6cc | 5119 | unsigned int inside_prec = TYPE_PRECISION (inside_type); |
7e139075 RK |
5120 | int inside_unsignedp = TREE_UNSIGNED (inside_type); |
5121 | int inter_int = INTEGRAL_TYPE_P (inter_type); | |
7f0b305c | 5122 | int inter_ptr = POINTER_TYPE_P (inter_type); |
7e139075 | 5123 | int inter_float = FLOAT_TYPE_P (inter_type); |
770ae6cc | 5124 | unsigned int inter_prec = TYPE_PRECISION (inter_type); |
7e139075 RK |
5125 | int inter_unsignedp = TREE_UNSIGNED (inter_type); |
5126 | int final_int = INTEGRAL_TYPE_P (final_type); | |
7f0b305c | 5127 | int final_ptr = POINTER_TYPE_P (final_type); |
7e139075 | 5128 | int final_float = FLOAT_TYPE_P (final_type); |
770ae6cc | 5129 | unsigned int final_prec = TYPE_PRECISION (final_type); |
7e139075 RK |
5130 | int final_unsignedp = TREE_UNSIGNED (final_type); |
5131 | ||
b6cc0a72 | 5132 | /* In addition to the cases of two conversions in a row |
7e139075 RK |
5133 | handled below, if we are converting something to its own |
5134 | type via an object of identical or wider precision, neither | |
5135 | conversion is needed. */ | |
30355eaa | 5136 | if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (final_type) |
7e139075 RK |
5137 | && ((inter_int && final_int) || (inter_float && final_float)) |
5138 | && inter_prec >= final_prec) | |
72bd1f9e | 5139 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
7e139075 RK |
5140 | |
5141 | /* Likewise, if the intermediate and final types are either both | |
5142 | float or both integer, we don't need the middle conversion if | |
5143 | it is wider than the final type and doesn't change the signedness | |
7f0b305c | 5144 | (for integers). Avoid this if the final type is a pointer |
410d3f5d RK |
5145 | since then we sometimes need the inner conversion. Likewise if |
5146 | the outer has a precision not equal to the size of its mode. */ | |
7e139075 RK |
5147 | if ((((inter_int || inter_ptr) && (inside_int || inside_ptr)) |
5148 | || (inter_float && inside_float)) | |
5149 | && inter_prec >= inside_prec | |
7f0b305c | 5150 | && (inter_float || inter_unsignedp == inside_unsignedp) |
410d3f5d RK |
5151 | && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type)) |
5152 | && TYPE_MODE (final_type) == TYPE_MODE (inter_type)) | |
7f0b305c | 5153 | && ! final_ptr) |
7e139075 RK |
5154 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
5155 | ||
ba3ad5e0 PDM |
5156 | /* If we have a sign-extension of a zero-extended value, we can |
5157 | replace that by a single zero-extension. */ | |
5158 | if (inside_int && inter_int && final_int | |
5159 | && inside_prec < inter_prec && inter_prec < final_prec | |
5160 | && inside_unsignedp && !inter_unsignedp) | |
5161 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
5162 | ||
7e139075 RK |
5163 | /* Two conversions in a row are not needed unless: |
5164 | - some conversion is floating-point (overstrict for now), or | |
5165 | - the intermediate type is narrower than both initial and | |
5166 | final, or | |
5167 | - the intermediate type and innermost type differ in signedness, | |
5168 | and the outermost type is wider than the intermediate, or | |
5169 | - the initial type is a pointer type and the precisions of the | |
5170 | intermediate and final types differ, or | |
b6cc0a72 | 5171 | - the final type is a pointer type and the precisions of the |
7e139075 RK |
5172 | initial and intermediate types differ. */ |
5173 | if (! inside_float && ! inter_float && ! final_float | |
5174 | && (inter_prec > inside_prec || inter_prec > final_prec) | |
5175 | && ! (inside_int && inter_int | |
5176 | && inter_unsignedp != inside_unsignedp | |
5177 | && inter_prec < final_prec) | |
5178 | && ((inter_unsignedp && inter_prec > inside_prec) | |
5179 | == (final_unsignedp && final_prec > inter_prec)) | |
5180 | && ! (inside_ptr && inter_prec != final_prec) | |
410d3f5d RK |
5181 | && ! (final_ptr && inside_prec != inter_prec) |
5182 | && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type)) | |
5183 | && TYPE_MODE (final_type) == TYPE_MODE (inter_type)) | |
5184 | && ! final_ptr) | |
7e139075 RK |
5185 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
5186 | } | |
6d716ca8 RS |
5187 | |
5188 | if (TREE_CODE (TREE_OPERAND (t, 0)) == MODIFY_EXPR | |
d8f6dbb9 RS |
5189 | && TREE_CONSTANT (TREE_OPERAND (TREE_OPERAND (t, 0), 1)) |
5190 | /* Detect assigning a bitfield. */ | |
5191 | && !(TREE_CODE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)) == COMPONENT_REF | |
5192 | && DECL_BIT_FIELD (TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (t, 0), 0), 1)))) | |
6d716ca8 | 5193 | { |
d8f6dbb9 | 5194 | /* Don't leave an assignment inside a conversion |
f72aed24 | 5195 | unless assigning a bitfield. */ |
6d716ca8 RS |
5196 | tree prev = TREE_OPERAND (t, 0); |
5197 | TREE_OPERAND (t, 0) = TREE_OPERAND (prev, 1); | |
5198 | /* First do the assignment, then return converted constant. */ | |
5199 | t = build (COMPOUND_EXPR, TREE_TYPE (t), prev, fold (t)); | |
5200 | TREE_USED (t) = 1; | |
5201 | return t; | |
5202 | } | |
5203 | if (!wins) | |
5204 | { | |
5205 | TREE_CONSTANT (t) = TREE_CONSTANT (arg0); | |
5206 | return t; | |
5207 | } | |
5208 | return fold_convert (t, arg0); | |
5209 | ||
5210 | #if 0 /* This loses on &"foo"[0]. */ | |
5211 | case ARRAY_REF: | |
5212 | { | |
5213 | int i; | |
5214 | ||
5215 | /* Fold an expression like: "foo"[2] */ | |
5216 | if (TREE_CODE (arg0) == STRING_CST | |
5217 | && TREE_CODE (arg1) == INTEGER_CST | |
05bccae2 | 5218 | && compare_tree_int (arg1, TREE_STRING_LENGTH (arg0)) < 0) |
6d716ca8 | 5219 | { |
05bccae2 | 5220 | t = build_int_2 (TREE_STRING_POINTER (arg0)[TREE_INT_CST_LOW (arg))], 0); |
6d716ca8 | 5221 | TREE_TYPE (t) = TREE_TYPE (TREE_TYPE (arg0)); |
ef2bf0c0 | 5222 | force_fit_type (t, 0); |
6d716ca8 RS |
5223 | } |
5224 | } | |
5225 | return t; | |
5226 | #endif /* 0 */ | |
5227 | ||
e082358b JM |
5228 | case COMPONENT_REF: |
5229 | if (TREE_CODE (arg0) == CONSTRUCTOR) | |
3ac4f0e6 JM |
5230 | { |
5231 | tree m = purpose_member (arg1, CONSTRUCTOR_ELTS (arg0)); | |
5232 | if (m) | |
5233 | t = TREE_VALUE (m); | |
5234 | } | |
e082358b JM |
5235 | return t; |
5236 | ||
6d716ca8 RS |
5237 | case RANGE_EXPR: |
5238 | TREE_CONSTANT (t) = wins; | |
5239 | return t; | |
5240 | ||
5241 | case NEGATE_EXPR: | |
5242 | if (wins) | |
5243 | { | |
5244 | if (TREE_CODE (arg0) == INTEGER_CST) | |
5245 | { | |
f9e158c3 JM |
5246 | unsigned HOST_WIDE_INT low; |
5247 | HOST_WIDE_INT high; | |
fe3e8e40 RS |
5248 | int overflow = neg_double (TREE_INT_CST_LOW (arg0), |
5249 | TREE_INT_CST_HIGH (arg0), | |
5250 | &low, &high); | |
5251 | t = build_int_2 (low, high); | |
6d716ca8 | 5252 | TREE_TYPE (t) = type; |
dc3907c5 PE |
5253 | TREE_OVERFLOW (t) |
5254 | = (TREE_OVERFLOW (arg0) | |
0c9cabe7 | 5255 | | force_fit_type (t, overflow && !TREE_UNSIGNED (type))); |
dc3907c5 PE |
5256 | TREE_CONSTANT_OVERFLOW (t) |
5257 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0); | |
6d716ca8 RS |
5258 | } |
5259 | else if (TREE_CODE (arg0) == REAL_CST) | |
5260 | t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0))); | |
6d716ca8 RS |
5261 | } |
5262 | else if (TREE_CODE (arg0) == NEGATE_EXPR) | |
5263 | return TREE_OPERAND (arg0, 0); | |
5264 | ||
5265 | /* Convert - (a - b) to (b - a) for non-floating-point. */ | |
1baa375f | 5266 | else if (TREE_CODE (arg0) == MINUS_EXPR |
de6c5979 | 5267 | && (! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations)) |
6d716ca8 RS |
5268 | return build (MINUS_EXPR, type, TREE_OPERAND (arg0, 1), |
5269 | TREE_OPERAND (arg0, 0)); | |
5270 | ||
5271 | return t; | |
5272 | ||
5273 | case ABS_EXPR: | |
5274 | if (wins) | |
5275 | { | |
5276 | if (TREE_CODE (arg0) == INTEGER_CST) | |
5277 | { | |
68e568c2 MM |
5278 | /* If the value is unsigned, then the absolute value is |
5279 | the same as the ordinary value. */ | |
5280 | if (TREE_UNSIGNED (type)) | |
5281 | return arg0; | |
5282 | /* Similarly, if the value is non-negative. */ | |
5283 | else if (INT_CST_LT (integer_minus_one_node, arg0)) | |
5284 | return arg0; | |
5285 | /* If the value is negative, then the absolute value is | |
5286 | its negation. */ | |
5287 | else | |
6d716ca8 | 5288 | { |
f9e158c3 JM |
5289 | unsigned HOST_WIDE_INT low; |
5290 | HOST_WIDE_INT high; | |
2a23183e RS |
5291 | int overflow = neg_double (TREE_INT_CST_LOW (arg0), |
5292 | TREE_INT_CST_HIGH (arg0), | |
5293 | &low, &high); | |
5294 | t = build_int_2 (low, high); | |
5295 | TREE_TYPE (t) = type; | |
dc3907c5 PE |
5296 | TREE_OVERFLOW (t) |
5297 | = (TREE_OVERFLOW (arg0) | |
e0f776fb | 5298 | | force_fit_type (t, overflow)); |
dc3907c5 PE |
5299 | TREE_CONSTANT_OVERFLOW (t) |
5300 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0); | |
6d716ca8 RS |
5301 | } |
5302 | } | |
5303 | else if (TREE_CODE (arg0) == REAL_CST) | |
5304 | { | |
c05a9b68 | 5305 | if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0))) |
6d716ca8 RS |
5306 | t = build_real (type, |
5307 | REAL_VALUE_NEGATE (TREE_REAL_CST (arg0))); | |
5308 | } | |
6d716ca8 RS |
5309 | } |
5310 | else if (TREE_CODE (arg0) == ABS_EXPR || TREE_CODE (arg0) == NEGATE_EXPR) | |
5311 | return build1 (ABS_EXPR, type, TREE_OPERAND (arg0, 0)); | |
5312 | return t; | |
5313 | ||
551064b1 RS |
5314 | case CONJ_EXPR: |
5315 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) | |
13eb1f7f | 5316 | return convert (type, arg0); |
551064b1 | 5317 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) |
c9869b75 | 5318 | return build (COMPLEX_EXPR, type, |
551064b1 | 5319 | TREE_OPERAND (arg0, 0), |
1baa375f | 5320 | negate_expr (TREE_OPERAND (arg0, 1))); |
551064b1 | 5321 | else if (TREE_CODE (arg0) == COMPLEX_CST) |
32812a40 JM |
5322 | return build_complex (type, TREE_REALPART (arg0), |
5323 | negate_expr (TREE_IMAGPART (arg0))); | |
551064b1 RS |
5324 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) |
5325 | return fold (build (TREE_CODE (arg0), type, | |
5326 | fold (build1 (CONJ_EXPR, type, | |
5327 | TREE_OPERAND (arg0, 0))), | |
5328 | fold (build1 (CONJ_EXPR, | |
5329 | type, TREE_OPERAND (arg0, 1))))); | |
5330 | else if (TREE_CODE (arg0) == CONJ_EXPR) | |
5331 | return TREE_OPERAND (arg0, 0); | |
5332 | return t; | |
5333 | ||
6d716ca8 RS |
5334 | case BIT_NOT_EXPR: |
5335 | if (wins) | |
5336 | { | |
380ff34a RK |
5337 | t = build_int_2 (~ TREE_INT_CST_LOW (arg0), |
5338 | ~ TREE_INT_CST_HIGH (arg0)); | |
6d716ca8 | 5339 | TREE_TYPE (t) = type; |
e0f776fb | 5340 | force_fit_type (t, 0); |
dc3907c5 | 5341 | TREE_OVERFLOW (t) = TREE_OVERFLOW (arg0); |
fe3e8e40 | 5342 | TREE_CONSTANT_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (arg0); |
6d716ca8 RS |
5343 | } |
5344 | else if (TREE_CODE (arg0) == BIT_NOT_EXPR) | |
5345 | return TREE_OPERAND (arg0, 0); | |
5346 | return t; | |
5347 | ||
5348 | case PLUS_EXPR: | |
5349 | /* A + (-B) -> A - B */ | |
5350 | if (TREE_CODE (arg1) == NEGATE_EXPR) | |
5351 | return fold (build (MINUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0))); | |
10414089 JL |
5352 | /* (-A) + B -> B - A */ |
5353 | if (TREE_CODE (arg0) == NEGATE_EXPR) | |
5354 | return fold (build (MINUS_EXPR, type, arg1, TREE_OPERAND (arg0, 0))); | |
7178e3af | 5355 | else if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
5356 | { |
5357 | if (integer_zerop (arg1)) | |
5358 | return non_lvalue (convert (type, arg0)); | |
5359 | ||
5360 | /* If we are adding two BIT_AND_EXPR's, both of which are and'ing | |
5361 | with a constant, and the two constants have no bits in common, | |
5362 | we should treat this as a BIT_IOR_EXPR since this may produce more | |
5363 | simplifications. */ | |
5364 | if (TREE_CODE (arg0) == BIT_AND_EXPR | |
5365 | && TREE_CODE (arg1) == BIT_AND_EXPR | |
5366 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
5367 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST | |
5368 | && integer_zerop (const_binop (BIT_AND_EXPR, | |
5369 | TREE_OPERAND (arg0, 1), | |
91d33e36 | 5370 | TREE_OPERAND (arg1, 1), 0))) |
6d716ca8 RS |
5371 | { |
5372 | code = BIT_IOR_EXPR; | |
5373 | goto bit_ior; | |
5374 | } | |
6a96fcb4 | 5375 | |
abe4f192 | 5376 | /* Reassociate (plus (plus (mult) (foo)) (mult)) as |
b6cc0a72 | 5377 | (plus (plus (mult) (mult)) (foo)) so that we can |
abe4f192 RH |
5378 | take advantage of the factoring cases below. */ |
5379 | if ((TREE_CODE (arg0) == PLUS_EXPR | |
5380 | && TREE_CODE (arg1) == MULT_EXPR) | |
5381 | || (TREE_CODE (arg1) == PLUS_EXPR | |
b6cc0a72 | 5382 | && TREE_CODE (arg0) == MULT_EXPR)) |
abe4f192 RH |
5383 | { |
5384 | tree parg0, parg1, parg, marg; | |
5385 | ||
5386 | if (TREE_CODE (arg0) == PLUS_EXPR) | |
5387 | parg = arg0, marg = arg1; | |
5388 | else | |
5389 | parg = arg1, marg = arg0; | |
5390 | parg0 = TREE_OPERAND (parg, 0); | |
5391 | parg1 = TREE_OPERAND (parg, 1); | |
5392 | STRIP_NOPS (parg0); | |
5393 | STRIP_NOPS (parg1); | |
5394 | ||
5395 | if (TREE_CODE (parg0) == MULT_EXPR | |
5396 | && TREE_CODE (parg1) != MULT_EXPR) | |
5397 | return fold (build (PLUS_EXPR, type, | |
5398 | fold (build (PLUS_EXPR, type, parg0, marg)), | |
5399 | parg1)); | |
5400 | if (TREE_CODE (parg0) != MULT_EXPR | |
5401 | && TREE_CODE (parg1) == MULT_EXPR) | |
5402 | return fold (build (PLUS_EXPR, type, | |
5403 | fold (build (PLUS_EXPR, type, parg1, marg)), | |
5404 | parg0)); | |
5405 | } | |
5406 | ||
45f97e2e RH |
5407 | if (TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (arg1) == MULT_EXPR) |
5408 | { | |
5409 | tree arg00, arg01, arg10, arg11; | |
07444f1d | 5410 | tree alt0 = NULL_TREE, alt1 = NULL_TREE, same; |
45f97e2e RH |
5411 | |
5412 | /* (A * C) + (B * C) -> (A+B) * C. | |
5413 | We are most concerned about the case where C is a constant, | |
5414 | but other combinations show up during loop reduction. Since | |
5415 | it is not difficult, try all four possibilities. */ | |
5416 | ||
5417 | arg00 = TREE_OPERAND (arg0, 0); | |
5418 | arg01 = TREE_OPERAND (arg0, 1); | |
5419 | arg10 = TREE_OPERAND (arg1, 0); | |
5420 | arg11 = TREE_OPERAND (arg1, 1); | |
5421 | same = NULL_TREE; | |
5422 | ||
5423 | if (operand_equal_p (arg01, arg11, 0)) | |
5424 | same = arg01, alt0 = arg00, alt1 = arg10; | |
5425 | else if (operand_equal_p (arg00, arg10, 0)) | |
5426 | same = arg00, alt0 = arg01, alt1 = arg11; | |
5427 | else if (operand_equal_p (arg00, arg11, 0)) | |
5428 | same = arg00, alt0 = arg01, alt1 = arg10; | |
5429 | else if (operand_equal_p (arg01, arg10, 0)) | |
5430 | same = arg01, alt0 = arg00, alt1 = arg11; | |
5431 | ||
abe4f192 RH |
5432 | /* No identical multiplicands; see if we can find a common |
5433 | power-of-two factor in non-power-of-two multiplies. This | |
5434 | can help in multi-dimensional array access. */ | |
5435 | else if (TREE_CODE (arg01) == INTEGER_CST | |
5436 | && TREE_CODE (arg11) == INTEGER_CST | |
5437 | && TREE_INT_CST_HIGH (arg01) == 0 | |
5438 | && TREE_INT_CST_HIGH (arg11) == 0) | |
5439 | { | |
5440 | HOST_WIDE_INT int01, int11, tmp; | |
5441 | int01 = TREE_INT_CST_LOW (arg01); | |
5442 | int11 = TREE_INT_CST_LOW (arg11); | |
5443 | ||
5444 | /* Move min of absolute values to int11. */ | |
5445 | if ((int01 >= 0 ? int01 : -int01) | |
5446 | < (int11 >= 0 ? int11 : -int11)) | |
5447 | { | |
5448 | tmp = int01, int01 = int11, int11 = tmp; | |
5449 | alt0 = arg00, arg00 = arg10, arg10 = alt0; | |
5450 | alt0 = arg01, arg01 = arg11, arg11 = alt0; | |
5451 | } | |
5452 | ||
5453 | if (exact_log2 (int11) > 0 && int01 % int11 == 0) | |
5454 | { | |
5455 | alt0 = fold (build (MULT_EXPR, type, arg00, | |
5456 | build_int_2 (int01 / int11, 0))); | |
5457 | alt1 = arg10; | |
5458 | same = arg11; | |
5459 | } | |
5460 | } | |
5461 | ||
45f97e2e | 5462 | if (same) |
b6cc0a72 | 5463 | return fold (build (MULT_EXPR, type, |
45f97e2e RH |
5464 | fold (build (PLUS_EXPR, type, alt0, alt1)), |
5465 | same)); | |
5466 | } | |
6d716ca8 RS |
5467 | } |
5468 | /* In IEEE floating point, x+0 may not equal x. */ | |
996c63d3 | 5469 | else if ((TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
de6c5979 | 5470 | || flag_unsafe_math_optimizations) |
6d716ca8 RS |
5471 | && real_zerop (arg1)) |
5472 | return non_lvalue (convert (type, arg0)); | |
10414089 | 5473 | /* x+(-0) equals x, even for IEEE. */ |
2af3e5fb AB |
5474 | else if (TREE_CODE (arg1) == REAL_CST |
5475 | && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (arg1))) | |
10414089 JL |
5476 | return non_lvalue (convert (type, arg0)); |
5477 | ||
79e8185c JH |
5478 | bit_rotate: |
5479 | /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A | |
5480 | is a rotate of A by C1 bits. */ | |
5481 | /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A | |
5482 | is a rotate of A by B bits. */ | |
5483 | { | |
b6cc0a72 KH |
5484 | register enum tree_code code0, code1; |
5485 | code0 = TREE_CODE (arg0); | |
5486 | code1 = TREE_CODE (arg1); | |
5487 | if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR) | |
5488 | || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR)) | |
79e8185c | 5489 | && operand_equal_p (TREE_OPERAND (arg0, 0), |
b6cc0a72 | 5490 | TREE_OPERAND (arg1, 0), 0) |
79e8185c JH |
5491 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))) |
5492 | { | |
5493 | register tree tree01, tree11; | |
5494 | register enum tree_code code01, code11; | |
5495 | ||
5496 | tree01 = TREE_OPERAND (arg0, 1); | |
5497 | tree11 = TREE_OPERAND (arg1, 1); | |
5498 | STRIP_NOPS (tree01); | |
5499 | STRIP_NOPS (tree11); | |
5500 | code01 = TREE_CODE (tree01); | |
5501 | code11 = TREE_CODE (tree11); | |
5502 | if (code01 == INTEGER_CST | |
b6cc0a72 KH |
5503 | && code11 == INTEGER_CST |
5504 | && TREE_INT_CST_HIGH (tree01) == 0 | |
5505 | && TREE_INT_CST_HIGH (tree11) == 0 | |
5506 | && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11)) | |
5507 | == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))))) | |
79e8185c | 5508 | return build (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0), |
b6cc0a72 | 5509 | code0 == LSHIFT_EXPR ? tree01 : tree11); |
79e8185c JH |
5510 | else if (code11 == MINUS_EXPR) |
5511 | { | |
b6cc0a72 KH |
5512 | tree tree110, tree111; |
5513 | tree110 = TREE_OPERAND (tree11, 0); | |
5514 | tree111 = TREE_OPERAND (tree11, 1); | |
5515 | STRIP_NOPS (tree110); | |
5516 | STRIP_NOPS (tree111); | |
5517 | if (TREE_CODE (tree110) == INTEGER_CST | |
05bccae2 RK |
5518 | && 0 == compare_tree_int (tree110, |
5519 | TYPE_PRECISION | |
5520 | (TREE_TYPE (TREE_OPERAND | |
5521 | (arg0, 0)))) | |
79e8185c | 5522 | && operand_equal_p (tree01, tree111, 0)) |
b6cc0a72 KH |
5523 | return build ((code0 == LSHIFT_EXPR |
5524 | ? LROTATE_EXPR | |
5525 | : RROTATE_EXPR), | |
5526 | type, TREE_OPERAND (arg0, 0), tree01); | |
79e8185c JH |
5527 | } |
5528 | else if (code01 == MINUS_EXPR) | |
5529 | { | |
b6cc0a72 KH |
5530 | tree tree010, tree011; |
5531 | tree010 = TREE_OPERAND (tree01, 0); | |
5532 | tree011 = TREE_OPERAND (tree01, 1); | |
5533 | STRIP_NOPS (tree010); | |
5534 | STRIP_NOPS (tree011); | |
5535 | if (TREE_CODE (tree010) == INTEGER_CST | |
05bccae2 RK |
5536 | && 0 == compare_tree_int (tree010, |
5537 | TYPE_PRECISION | |
5538 | (TREE_TYPE (TREE_OPERAND | |
5539 | (arg0, 0)))) | |
79e8185c | 5540 | && operand_equal_p (tree11, tree011, 0)) |
b6cc0a72 KH |
5541 | return build ((code0 != LSHIFT_EXPR |
5542 | ? LROTATE_EXPR | |
5543 | : RROTATE_EXPR), | |
5544 | type, TREE_OPERAND (arg0, 0), tree11); | |
79e8185c JH |
5545 | } |
5546 | } | |
5547 | } | |
10414089 | 5548 | |
6d716ca8 | 5549 | associate: |
1baa375f RK |
5550 | /* In most languages, can't associate operations on floats through |
5551 | parentheses. Rather than remember where the parentheses were, we | |
5552 | don't associate floats at all. It shouldn't matter much. However, | |
5553 | associating multiplications is only very slightly inaccurate, so do | |
de6c5979 | 5554 | that if -funsafe-math-optimizations is specified. */ |
1baa375f RK |
5555 | |
5556 | if (! wins | |
5557 | && (! FLOAT_TYPE_P (type) | |
de6c5979 | 5558 | || (flag_unsafe_math_optimizations && code == MULT_EXPR))) |
6d716ca8 | 5559 | { |
1baa375f RK |
5560 | tree var0, con0, lit0, var1, con1, lit1; |
5561 | ||
5562 | /* Split both trees into variables, constants, and literals. Then | |
5563 | associate each group together, the constants with literals, | |
5564 | then the result with variables. This increases the chances of | |
5565 | literals being recombined later and of generating relocatable | |
5566 | expressions for the sum of a constant and literal. */ | |
5567 | var0 = split_tree (arg0, code, &con0, &lit0, 0); | |
5568 | var1 = split_tree (arg1, code, &con1, &lit1, code == MINUS_EXPR); | |
5569 | ||
5570 | /* Only do something if we found more than two objects. Otherwise, | |
5571 | nothing has changed and we risk infinite recursion. */ | |
5572 | if (2 < ((var0 != 0) + (var1 != 0) + (con0 != 0) + (con1 != 0) | |
5573 | + (lit0 != 0) + (lit1 != 0))) | |
6d716ca8 | 5574 | { |
1baa375f RK |
5575 | var0 = associate_trees (var0, var1, code, type); |
5576 | con0 = associate_trees (con0, con1, code, type); | |
5577 | lit0 = associate_trees (lit0, lit1, code, type); | |
5578 | con0 = associate_trees (con0, lit0, code, type); | |
5579 | return convert (type, associate_trees (var0, con0, code, type)); | |
6d716ca8 RS |
5580 | } |
5581 | } | |
1baa375f | 5582 | |
6d716ca8 RS |
5583 | binary: |
5584 | #if defined (REAL_IS_NOT_DOUBLE) && ! defined (REAL_ARITHMETIC) | |
5585 | if (TREE_CODE (arg1) == REAL_CST) | |
5586 | return t; | |
5587 | #endif /* REAL_IS_NOT_DOUBLE, and no REAL_ARITHMETIC */ | |
5588 | if (wins) | |
91d33e36 | 5589 | t1 = const_binop (code, arg0, arg1, 0); |
6d716ca8 RS |
5590 | if (t1 != NULL_TREE) |
5591 | { | |
5592 | /* The return value should always have | |
5593 | the same type as the original expression. */ | |
380ff34a RK |
5594 | if (TREE_TYPE (t1) != TREE_TYPE (t)) |
5595 | t1 = convert (TREE_TYPE (t), t1); | |
5596 | ||
6d716ca8 RS |
5597 | return t1; |
5598 | } | |
5599 | return t; | |
5600 | ||
5601 | case MINUS_EXPR: | |
10414089 JL |
5602 | /* A - (-B) -> A + B */ |
5603 | if (TREE_CODE (arg1) == NEGATE_EXPR) | |
5604 | return fold (build (PLUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0))); | |
5605 | /* (-A) - CST -> (-CST) - A for floating point (what about ints ?) */ | |
5606 | if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == REAL_CST) | |
5607 | return | |
b6cc0a72 | 5608 | fold (build (MINUS_EXPR, type, |
10414089 JL |
5609 | build_real (TREE_TYPE (arg1), |
5610 | REAL_VALUE_NEGATE (TREE_REAL_CST (arg1))), | |
5611 | TREE_OPERAND (arg0, 0))); | |
5612 | ||
7178e3af | 5613 | if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
5614 | { |
5615 | if (! wins && integer_zerop (arg0)) | |
b8fbe62c | 5616 | return negate_expr (convert (type, arg1)); |
6d716ca8 RS |
5617 | if (integer_zerop (arg1)) |
5618 | return non_lvalue (convert (type, arg0)); | |
6a96fcb4 RK |
5619 | |
5620 | /* (A * C) - (B * C) -> (A-B) * C. Since we are most concerned | |
5621 | about the case where C is a constant, just try one of the | |
5622 | four possibilities. */ | |
5623 | ||
5624 | if (TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (arg1) == MULT_EXPR | |
5625 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
5626 | TREE_OPERAND (arg1, 1), 0)) | |
5627 | return fold (build (MULT_EXPR, type, | |
5628 | fold (build (MINUS_EXPR, type, | |
5629 | TREE_OPERAND (arg0, 0), | |
5630 | TREE_OPERAND (arg1, 0))), | |
5631 | TREE_OPERAND (arg0, 1))); | |
6d716ca8 | 5632 | } |
fab446b8 RK |
5633 | |
5634 | else if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT | |
de6c5979 | 5635 | || flag_unsafe_math_optimizations) |
6d716ca8 | 5636 | { |
c05a9b68 | 5637 | /* Except with IEEE floating point, 0-x equals -x. */ |
6d716ca8 | 5638 | if (! wins && real_zerop (arg0)) |
b8fbe62c | 5639 | return negate_expr (convert (type, arg1)); |
c05a9b68 RS |
5640 | /* Except with IEEE floating point, x-0 equals x. */ |
5641 | if (real_zerop (arg1)) | |
6d716ca8 | 5642 | return non_lvalue (convert (type, arg0)); |
fab446b8 | 5643 | } |
a6acbe15 | 5644 | |
b6cc0a72 | 5645 | /* Fold &x - &x. This can happen from &x.foo - &x. |
fab446b8 RK |
5646 | This is unsafe for certain floats even in non-IEEE formats. |
5647 | In IEEE, it is unsafe because it does wrong for NaNs. | |
5648 | Also note that operand_equal_p is always false if an operand | |
5649 | is volatile. */ | |
5650 | ||
de6c5979 | 5651 | if ((! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations) |
59d90212 | 5652 | && operand_equal_p (arg0, arg1, 0)) |
fab446b8 | 5653 | return convert (type, integer_zero_node); |
a6acbe15 | 5654 | |
6d716ca8 RS |
5655 | goto associate; |
5656 | ||
5657 | case MULT_EXPR: | |
10414089 JL |
5658 | /* (-A) * (-B) -> A * B */ |
5659 | if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == NEGATE_EXPR) | |
5660 | return fold (build (MULT_EXPR, type, TREE_OPERAND (arg0, 0), | |
b6cc0a72 | 5661 | TREE_OPERAND (arg1, 0))); |
10414089 | 5662 | |
7178e3af | 5663 | if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
5664 | { |
5665 | if (integer_zerop (arg1)) | |
5666 | return omit_one_operand (type, arg1, arg0); | |
5667 | if (integer_onep (arg1)) | |
5668 | return non_lvalue (convert (type, arg0)); | |
5669 | ||
5670 | /* (a * (1 << b)) is (a << b) */ | |
5671 | if (TREE_CODE (arg1) == LSHIFT_EXPR | |
5672 | && integer_onep (TREE_OPERAND (arg1, 0))) | |
5673 | return fold (build (LSHIFT_EXPR, type, arg0, | |
5674 | TREE_OPERAND (arg1, 1))); | |
5675 | if (TREE_CODE (arg0) == LSHIFT_EXPR | |
5676 | && integer_onep (TREE_OPERAND (arg0, 0))) | |
5677 | return fold (build (LSHIFT_EXPR, type, arg1, | |
5678 | TREE_OPERAND (arg0, 1))); | |
1baa375f RK |
5679 | |
5680 | if (TREE_CODE (arg1) == INTEGER_CST | |
5681 | && 0 != (tem = extract_muldiv (TREE_OPERAND (t, 0), arg1, | |
5682 | code, NULL_TREE))) | |
5683 | return convert (type, tem); | |
5684 | ||
6d716ca8 | 5685 | } |
6d716ca8 RS |
5686 | else |
5687 | { | |
c05a9b68 | 5688 | /* x*0 is 0, except for IEEE floating point. */ |
fab446b8 | 5689 | if ((TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
de6c5979 | 5690 | || flag_unsafe_math_optimizations) |
6d716ca8 RS |
5691 | && real_zerop (arg1)) |
5692 | return omit_one_operand (type, arg1, arg0); | |
c05a9b68 | 5693 | /* In IEEE floating point, x*1 is not equivalent to x for snans. |
6d716ca8 RS |
5694 | However, ANSI says we can drop signals, |
5695 | so we can do this anyway. */ | |
5696 | if (real_onep (arg1)) | |
5697 | return non_lvalue (convert (type, arg0)); | |
5698 | /* x*2 is x+x */ | |
c5c76735 | 5699 | if (! wins && real_twop (arg1) && global_bindings_p () == 0 |
9ec36da5 | 5700 | && ! contains_placeholder_p (arg0)) |
6d716ca8 RS |
5701 | { |
5702 | tree arg = save_expr (arg0); | |
5703 | return build (PLUS_EXPR, type, arg, arg); | |
5704 | } | |
5705 | } | |
5706 | goto associate; | |
5707 | ||
5708 | case BIT_IOR_EXPR: | |
5709 | bit_ior: | |
5710 | if (integer_all_onesp (arg1)) | |
5711 | return omit_one_operand (type, arg1, arg0); | |
5712 | if (integer_zerop (arg1)) | |
5713 | return non_lvalue (convert (type, arg0)); | |
5714 | t1 = distribute_bit_expr (code, type, arg0, arg1); | |
5715 | if (t1 != NULL_TREE) | |
5716 | return t1; | |
85d2e16c | 5717 | |
ccc5fd95 JH |
5718 | /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))). |
5719 | ||
b6cc0a72 | 5720 | This results in more efficient code for machines without a NAND |
ccc5fd95 JH |
5721 | instruction. Combine will canonicalize to the first form |
5722 | which will allow use of NAND instructions provided by the | |
5723 | backend if they exist. */ | |
5724 | if (TREE_CODE (arg0) == BIT_NOT_EXPR | |
5725 | && TREE_CODE (arg1) == BIT_NOT_EXPR) | |
5726 | { | |
5727 | return fold (build1 (BIT_NOT_EXPR, type, | |
5728 | build (BIT_AND_EXPR, type, | |
5729 | TREE_OPERAND (arg0, 0), | |
5730 | TREE_OPERAND (arg1, 0)))); | |
5731 | } | |
5732 | ||
79e8185c JH |
5733 | /* See if this can be simplified into a rotate first. If that |
5734 | is unsuccessful continue in the association code. */ | |
5735 | goto bit_rotate; | |
6d716ca8 RS |
5736 | |
5737 | case BIT_XOR_EXPR: | |
5738 | if (integer_zerop (arg1)) | |
5739 | return non_lvalue (convert (type, arg0)); | |
5740 | if (integer_all_onesp (arg1)) | |
5741 | return fold (build1 (BIT_NOT_EXPR, type, arg0)); | |
79e8185c JH |
5742 | |
5743 | /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing | |
5744 | with a constant, and the two constants have no bits in common, | |
5745 | we should treat this as a BIT_IOR_EXPR since this may produce more | |
5746 | simplifications. */ | |
5747 | if (TREE_CODE (arg0) == BIT_AND_EXPR | |
5748 | && TREE_CODE (arg1) == BIT_AND_EXPR | |
5749 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
5750 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST | |
5751 | && integer_zerop (const_binop (BIT_AND_EXPR, | |
5752 | TREE_OPERAND (arg0, 1), | |
5753 | TREE_OPERAND (arg1, 1), 0))) | |
b6cc0a72 KH |
5754 | { |
5755 | code = BIT_IOR_EXPR; | |
5756 | goto bit_ior; | |
5757 | } | |
79e8185c | 5758 | |
03e0a65f | 5759 | /* See if this can be simplified into a rotate first. If that |
79e8185c | 5760 | is unsuccessful continue in the association code. */ |
03e0a65f | 5761 | goto bit_rotate; |
6d716ca8 RS |
5762 | |
5763 | case BIT_AND_EXPR: | |
5764 | bit_and: | |
5765 | if (integer_all_onesp (arg1)) | |
5766 | return non_lvalue (convert (type, arg0)); | |
5767 | if (integer_zerop (arg1)) | |
5768 | return omit_one_operand (type, arg1, arg0); | |
5769 | t1 = distribute_bit_expr (code, type, arg0, arg1); | |
5770 | if (t1 != NULL_TREE) | |
5771 | return t1; | |
5772 | /* Simplify ((int)c & 0x377) into (int)c, if c is unsigned char. */ | |
5773 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == NOP_EXPR | |
5774 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg1, 0)))) | |
5775 | { | |
770ae6cc RK |
5776 | unsigned int prec |
5777 | = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg1, 0))); | |
5778 | ||
906c4e36 RK |
5779 | if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT |
5780 | && (~TREE_INT_CST_LOW (arg0) | |
5781 | & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0) | |
6d716ca8 RS |
5782 | return build1 (NOP_EXPR, type, TREE_OPERAND (arg1, 0)); |
5783 | } | |
5784 | if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR | |
5785 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))) | |
5786 | { | |
770ae6cc RK |
5787 | unsigned int prec |
5788 | = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))); | |
5789 | ||
906c4e36 RK |
5790 | if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT |
5791 | && (~TREE_INT_CST_LOW (arg1) | |
5792 | & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0) | |
6d716ca8 RS |
5793 | return build1 (NOP_EXPR, type, TREE_OPERAND (arg0, 0)); |
5794 | } | |
ccc5fd95 | 5795 | |
a36335da | 5796 | /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))). |
ccc5fd95 | 5797 | |
b6cc0a72 | 5798 | This results in more efficient code for machines without a NOR |
ccc5fd95 JH |
5799 | instruction. Combine will canonicalize to the first form |
5800 | which will allow use of NOR instructions provided by the | |
5801 | backend if they exist. */ | |
5802 | if (TREE_CODE (arg0) == BIT_NOT_EXPR | |
5803 | && TREE_CODE (arg1) == BIT_NOT_EXPR) | |
5804 | { | |
5805 | return fold (build1 (BIT_NOT_EXPR, type, | |
5806 | build (BIT_IOR_EXPR, type, | |
5807 | TREE_OPERAND (arg0, 0), | |
5808 | TREE_OPERAND (arg1, 0)))); | |
5809 | } | |
5810 | ||
6d716ca8 RS |
5811 | goto associate; |
5812 | ||
5813 | case BIT_ANDTC_EXPR: | |
5814 | if (integer_all_onesp (arg0)) | |
5815 | return non_lvalue (convert (type, arg1)); | |
5816 | if (integer_zerop (arg0)) | |
5817 | return omit_one_operand (type, arg0, arg1); | |
5818 | if (TREE_CODE (arg1) == INTEGER_CST) | |
5819 | { | |
5820 | arg1 = fold (build1 (BIT_NOT_EXPR, type, arg1)); | |
5821 | code = BIT_AND_EXPR; | |
5822 | goto bit_and; | |
5823 | } | |
5824 | goto binary; | |
5825 | ||
e9aaa5a5 RK |
5826 | case RDIV_EXPR: |
5827 | /* In most cases, do nothing with a divide by zero. */ | |
5828 | #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) | |
5829 | #ifndef REAL_INFINITY | |
5830 | if (TREE_CODE (arg1) == REAL_CST && real_zerop (arg1)) | |
5831 | return t; | |
5832 | #endif | |
5833 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
5834 | ||
10414089 JL |
5835 | /* (-A) / (-B) -> A / B */ |
5836 | if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == NEGATE_EXPR) | |
5837 | return fold (build (RDIV_EXPR, type, TREE_OPERAND (arg0, 0), | |
5838 | TREE_OPERAND (arg1, 0))); | |
5839 | ||
e9aaa5a5 RK |
5840 | /* In IEEE floating point, x/1 is not equivalent to x for snans. |
5841 | However, ANSI says we can drop signals, so we can do this anyway. */ | |
5842 | if (real_onep (arg1)) | |
5843 | return non_lvalue (convert (type, arg0)); | |
5844 | ||
5845 | /* If ARG1 is a constant, we can convert this to a multiply by the | |
5846 | reciprocal. This does not have the same rounding properties, | |
de6c5979 BL |
5847 | so only do this if -funsafe-math-optimizations. We can actually |
5848 | always safely do it if ARG1 is a power of two, but it's hard to | |
5849 | tell if it is or not in a portable manner. */ | |
39647dcb RK |
5850 | if (TREE_CODE (arg1) == REAL_CST) |
5851 | { | |
de6c5979 | 5852 | if (flag_unsafe_math_optimizations |
39647dcb RK |
5853 | && 0 != (tem = const_binop (code, build_real (type, dconst1), |
5854 | arg1, 0))) | |
5855 | return fold (build (MULT_EXPR, type, arg0, tem)); | |
5856 | /* Find the reciprocal if optimizing and the result is exact. */ | |
5857 | else if (optimize) | |
5858 | { | |
5859 | REAL_VALUE_TYPE r; | |
5860 | r = TREE_REAL_CST (arg1); | |
5861 | if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r)) | |
b6cc0a72 KH |
5862 | { |
5863 | tem = build_real (type, r); | |
5864 | return fold (build (MULT_EXPR, type, arg0, tem)); | |
5865 | } | |
39647dcb RK |
5866 | } |
5867 | } | |
e9aaa5a5 RK |
5868 | goto binary; |
5869 | ||
6d716ca8 RS |
5870 | case TRUNC_DIV_EXPR: |
5871 | case ROUND_DIV_EXPR: | |
5872 | case FLOOR_DIV_EXPR: | |
5873 | case CEIL_DIV_EXPR: | |
5874 | case EXACT_DIV_EXPR: | |
6d716ca8 RS |
5875 | if (integer_onep (arg1)) |
5876 | return non_lvalue (convert (type, arg0)); | |
5877 | if (integer_zerop (arg1)) | |
5878 | return t; | |
3b998c11 | 5879 | |
39dfb55a JL |
5880 | /* If arg0 is a multiple of arg1, then rewrite to the fastest div |
5881 | operation, EXACT_DIV_EXPR. | |
5882 | ||
91585c63 TM |
5883 | Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now. |
5884 | At one time others generated faster code, it's not clear if they do | |
5885 | after the last round to changes to the DIV code in expmed.c. */ | |
5886 | if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR) | |
39dfb55a JL |
5887 | && multiple_of_p (type, arg0, arg1)) |
5888 | return fold (build (EXACT_DIV_EXPR, type, arg0, arg1)); | |
5889 | ||
b6cc0a72 | 5890 | if (TREE_CODE (arg1) == INTEGER_CST |
1baa375f RK |
5891 | && 0 != (tem = extract_muldiv (TREE_OPERAND (t, 0), arg1, |
5892 | code, NULL_TREE))) | |
5893 | return convert (type, tem); | |
3b998c11 | 5894 | |
6d716ca8 RS |
5895 | goto binary; |
5896 | ||
5897 | case CEIL_MOD_EXPR: | |
5898 | case FLOOR_MOD_EXPR: | |
5899 | case ROUND_MOD_EXPR: | |
5900 | case TRUNC_MOD_EXPR: | |
5901 | if (integer_onep (arg1)) | |
5902 | return omit_one_operand (type, integer_zero_node, arg0); | |
5903 | if (integer_zerop (arg1)) | |
5904 | return t; | |
6a96fcb4 | 5905 | |
6a96fcb4 | 5906 | if (TREE_CODE (arg1) == INTEGER_CST |
1baa375f RK |
5907 | && 0 != (tem = extract_muldiv (TREE_OPERAND (t, 0), arg1, |
5908 | code, NULL_TREE))) | |
5909 | return convert (type, tem); | |
6a96fcb4 | 5910 | |
6d716ca8 RS |
5911 | goto binary; |
5912 | ||
5913 | case LSHIFT_EXPR: | |
5914 | case RSHIFT_EXPR: | |
5915 | case LROTATE_EXPR: | |
5916 | case RROTATE_EXPR: | |
5917 | if (integer_zerop (arg1)) | |
5918 | return non_lvalue (convert (type, arg0)); | |
5919 | /* Since negative shift count is not well-defined, | |
5920 | don't try to compute it in the compiler. */ | |
4d39710e | 5921 | if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0) |
6d716ca8 | 5922 | return t; |
4d39710e RK |
5923 | /* Rewrite an LROTATE_EXPR by a constant into an |
5924 | RROTATE_EXPR by a new constant. */ | |
5925 | if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST) | |
5926 | { | |
5927 | TREE_SET_CODE (t, RROTATE_EXPR); | |
5928 | code = RROTATE_EXPR; | |
5929 | TREE_OPERAND (t, 1) = arg1 | |
5930 | = const_binop | |
5931 | (MINUS_EXPR, | |
5932 | convert (TREE_TYPE (arg1), | |
5933 | build_int_2 (GET_MODE_BITSIZE (TYPE_MODE (type)), 0)), | |
5934 | arg1, 0); | |
5935 | if (tree_int_cst_sgn (arg1) < 0) | |
5936 | return t; | |
5937 | } | |
5938 | ||
5939 | /* If we have a rotate of a bit operation with the rotate count and | |
5940 | the second operand of the bit operation both constant, | |
5941 | permute the two operations. */ | |
5942 | if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
5943 | && (TREE_CODE (arg0) == BIT_AND_EXPR | |
5944 | || TREE_CODE (arg0) == BIT_ANDTC_EXPR | |
5945 | || TREE_CODE (arg0) == BIT_IOR_EXPR | |
5946 | || TREE_CODE (arg0) == BIT_XOR_EXPR) | |
5947 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
5948 | return fold (build (TREE_CODE (arg0), type, | |
5949 | fold (build (code, type, | |
5950 | TREE_OPERAND (arg0, 0), arg1)), | |
5951 | fold (build (code, type, | |
5952 | TREE_OPERAND (arg0, 1), arg1)))); | |
5953 | ||
5954 | /* Two consecutive rotates adding up to the width of the mode can | |
5955 | be ignored. */ | |
5956 | if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
5957 | && TREE_CODE (arg0) == RROTATE_EXPR | |
5958 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
5959 | && TREE_INT_CST_HIGH (arg1) == 0 | |
5960 | && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0 | |
5961 | && ((TREE_INT_CST_LOW (arg1) | |
5962 | + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))) | |
05bccae2 | 5963 | == (unsigned int) GET_MODE_BITSIZE (TYPE_MODE (type)))) |
4d39710e RK |
5964 | return TREE_OPERAND (arg0, 0); |
5965 | ||
6d716ca8 RS |
5966 | goto binary; |
5967 | ||
5968 | case MIN_EXPR: | |
5969 | if (operand_equal_p (arg0, arg1, 0)) | |
13eb1f7f | 5970 | return omit_one_operand (type, arg0, arg1); |
7178e3af | 5971 | if (INTEGRAL_TYPE_P (type) |
6d716ca8 RS |
5972 | && operand_equal_p (arg1, TYPE_MIN_VALUE (type), 1)) |
5973 | return omit_one_operand (type, arg1, arg0); | |
5974 | goto associate; | |
5975 | ||
5976 | case MAX_EXPR: | |
5977 | if (operand_equal_p (arg0, arg1, 0)) | |
13eb1f7f | 5978 | return omit_one_operand (type, arg0, arg1); |
7178e3af | 5979 | if (INTEGRAL_TYPE_P (type) |
e1ee5cdc | 5980 | && TYPE_MAX_VALUE (type) |
6d716ca8 RS |
5981 | && operand_equal_p (arg1, TYPE_MAX_VALUE (type), 1)) |
5982 | return omit_one_operand (type, arg1, arg0); | |
5983 | goto associate; | |
5984 | ||
5985 | case TRUTH_NOT_EXPR: | |
5986 | /* Note that the operand of this must be an int | |
5987 | and its values must be 0 or 1. | |
5988 | ("true" is a fixed value perhaps depending on the language, | |
5989 | but we don't handle values other than 1 correctly yet.) */ | |
1180eb10 JM |
5990 | tem = invert_truthvalue (arg0); |
5991 | /* Avoid infinite recursion. */ | |
5992 | if (TREE_CODE (tem) == TRUTH_NOT_EXPR) | |
5993 | return t; | |
5994 | return convert (type, tem); | |
6d716ca8 RS |
5995 | |
5996 | case TRUTH_ANDIF_EXPR: | |
5997 | /* Note that the operands of this must be ints | |
5998 | and their values must be 0 or 1. | |
5999 | ("true" is a fixed value perhaps depending on the language.) */ | |
6000 | /* If first arg is constant zero, return it. */ | |
772447c5 | 6001 | if (integer_zerop (arg0)) |
13eb1f7f | 6002 | return convert (type, arg0); |
6d716ca8 RS |
6003 | case TRUTH_AND_EXPR: |
6004 | /* If either arg is constant true, drop it. */ | |
6005 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
13eb1f7f | 6006 | return non_lvalue (convert (type, arg1)); |
235cfbc4 BS |
6007 | if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1) |
6008 | /* Preserve sequence points. */ | |
6009 | && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0))) | |
13eb1f7f | 6010 | return non_lvalue (convert (type, arg0)); |
772447c5 RK |
6011 | /* If second arg is constant zero, result is zero, but first arg |
6012 | must be evaluated. */ | |
6013 | if (integer_zerop (arg1)) | |
6014 | return omit_one_operand (type, arg1, arg0); | |
80906567 RK |
6015 | /* Likewise for first arg, but note that only the TRUTH_AND_EXPR |
6016 | case will be handled here. */ | |
6017 | if (integer_zerop (arg0)) | |
6018 | return omit_one_operand (type, arg0, arg1); | |
6d716ca8 RS |
6019 | |
6020 | truth_andor: | |
e9b5e15f RK |
6021 | /* We only do these simplifications if we are optimizing. */ |
6022 | if (!optimize) | |
6023 | return t; | |
6024 | ||
6025 | /* Check for things like (A || B) && (A || C). We can convert this | |
6026 | to A || (B && C). Note that either operator can be any of the four | |
6027 | truth and/or operations and the transformation will still be | |
6028 | valid. Also note that we only care about order for the | |
96f06cb6 RK |
6029 | ANDIF and ORIF operators. If B contains side effects, this |
6030 | might change the truth-value of A. */ | |
e9b5e15f RK |
6031 | if (TREE_CODE (arg0) == TREE_CODE (arg1) |
6032 | && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR | |
6033 | || TREE_CODE (arg0) == TRUTH_ORIF_EXPR | |
6034 | || TREE_CODE (arg0) == TRUTH_AND_EXPR | |
96f06cb6 RK |
6035 | || TREE_CODE (arg0) == TRUTH_OR_EXPR) |
6036 | && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1))) | |
e9b5e15f RK |
6037 | { |
6038 | tree a00 = TREE_OPERAND (arg0, 0); | |
6039 | tree a01 = TREE_OPERAND (arg0, 1); | |
6040 | tree a10 = TREE_OPERAND (arg1, 0); | |
6041 | tree a11 = TREE_OPERAND (arg1, 1); | |
6042 | int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR | |
6043 | || TREE_CODE (arg0) == TRUTH_AND_EXPR) | |
6044 | && (code == TRUTH_AND_EXPR | |
6045 | || code == TRUTH_OR_EXPR)); | |
6046 | ||
6047 | if (operand_equal_p (a00, a10, 0)) | |
6048 | return fold (build (TREE_CODE (arg0), type, a00, | |
6049 | fold (build (code, type, a01, a11)))); | |
6050 | else if (commutative && operand_equal_p (a00, a11, 0)) | |
6051 | return fold (build (TREE_CODE (arg0), type, a00, | |
6052 | fold (build (code, type, a01, a10)))); | |
6053 | else if (commutative && operand_equal_p (a01, a10, 0)) | |
6054 | return fold (build (TREE_CODE (arg0), type, a01, | |
6055 | fold (build (code, type, a00, a11)))); | |
6056 | ||
6057 | /* This case if tricky because we must either have commutative | |
6058 | operators or else A10 must not have side-effects. */ | |
6059 | ||
6060 | else if ((commutative || ! TREE_SIDE_EFFECTS (a10)) | |
6061 | && operand_equal_p (a01, a11, 0)) | |
6062 | return fold (build (TREE_CODE (arg0), type, | |
6063 | fold (build (code, type, a00, a10)), | |
6064 | a01)); | |
6065 | } | |
6066 | ||
ebde8a27 RK |
6067 | /* See if we can build a range comparison. */ |
6068 | if (0 != (tem = fold_range_test (t))) | |
6069 | return tem; | |
6070 | ||
6d716ca8 RS |
6071 | /* Check for the possibility of merging component references. If our |
6072 | lhs is another similar operation, try to merge its rhs with our | |
6073 | rhs. Then try to merge our lhs and rhs. */ | |
e9b5e15f RK |
6074 | if (TREE_CODE (arg0) == code |
6075 | && 0 != (tem = fold_truthop (code, type, | |
6076 | TREE_OPERAND (arg0, 1), arg1))) | |
6077 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
6d716ca8 | 6078 | |
e9b5e15f RK |
6079 | if ((tem = fold_truthop (code, type, arg0, arg1)) != 0) |
6080 | return tem; | |
61f275ff | 6081 | |
6d716ca8 RS |
6082 | return t; |
6083 | ||
6084 | case TRUTH_ORIF_EXPR: | |
6085 | /* Note that the operands of this must be ints | |
6086 | and their values must be 0 or true. | |
6087 | ("true" is a fixed value perhaps depending on the language.) */ | |
6088 | /* If first arg is constant true, return it. */ | |
6089 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
13eb1f7f | 6090 | return convert (type, arg0); |
6d716ca8 RS |
6091 | case TRUTH_OR_EXPR: |
6092 | /* If either arg is constant zero, drop it. */ | |
6093 | if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0)) | |
13eb1f7f | 6094 | return non_lvalue (convert (type, arg1)); |
235cfbc4 BS |
6095 | if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1) |
6096 | /* Preserve sequence points. */ | |
6097 | && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0))) | |
13eb1f7f | 6098 | return non_lvalue (convert (type, arg0)); |
772447c5 RK |
6099 | /* If second arg is constant true, result is true, but we must |
6100 | evaluate first arg. */ | |
6101 | if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)) | |
6102 | return omit_one_operand (type, arg1, arg0); | |
80906567 RK |
6103 | /* Likewise for first arg, but note this only occurs here for |
6104 | TRUTH_OR_EXPR. */ | |
6105 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
6106 | return omit_one_operand (type, arg0, arg1); | |
6d716ca8 RS |
6107 | goto truth_andor; |
6108 | ||
772447c5 RK |
6109 | case TRUTH_XOR_EXPR: |
6110 | /* If either arg is constant zero, drop it. */ | |
6111 | if (integer_zerop (arg0)) | |
13eb1f7f | 6112 | return non_lvalue (convert (type, arg1)); |
772447c5 | 6113 | if (integer_zerop (arg1)) |
13eb1f7f | 6114 | return non_lvalue (convert (type, arg0)); |
772447c5 RK |
6115 | /* If either arg is constant true, this is a logical inversion. */ |
6116 | if (integer_onep (arg0)) | |
13eb1f7f | 6117 | return non_lvalue (convert (type, invert_truthvalue (arg1))); |
772447c5 | 6118 | if (integer_onep (arg1)) |
13eb1f7f | 6119 | return non_lvalue (convert (type, invert_truthvalue (arg0))); |
62d8b51e | 6120 | return t; |
772447c5 | 6121 | |
6d716ca8 RS |
6122 | case EQ_EXPR: |
6123 | case NE_EXPR: | |
6124 | case LT_EXPR: | |
6125 | case GT_EXPR: | |
6126 | case LE_EXPR: | |
6127 | case GE_EXPR: | |
10414089 JL |
6128 | if (FLOAT_TYPE_P (TREE_TYPE (arg0))) |
6129 | { | |
6130 | /* (-a) CMP (-b) -> b CMP a */ | |
6131 | if (TREE_CODE (arg0) == NEGATE_EXPR | |
6132 | && TREE_CODE (arg1) == NEGATE_EXPR) | |
6133 | return fold (build (code, type, TREE_OPERAND (arg1, 0), | |
6134 | TREE_OPERAND (arg0, 0))); | |
6135 | /* (-a) CMP CST -> a swap(CMP) (-CST) */ | |
6136 | if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == REAL_CST) | |
6137 | return | |
6138 | fold (build | |
b6cc0a72 KH |
6139 | (swap_tree_comparison (code), type, |
6140 | TREE_OPERAND (arg0, 0), | |
6141 | build_real (TREE_TYPE (arg1), | |
6142 | REAL_VALUE_NEGATE (TREE_REAL_CST (arg1))))); | |
10414089 JL |
6143 | /* IEEE doesn't distinguish +0 and -0 in comparisons. */ |
6144 | /* a CMP (-0) -> a CMP 0 */ | |
0d19c2a1 JL |
6145 | if (TREE_CODE (arg1) == REAL_CST |
6146 | && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (arg1))) | |
10414089 JL |
6147 | return fold (build (code, type, arg0, |
6148 | build_real (TREE_TYPE (arg1), dconst0))); | |
6149 | } | |
6150 | ||
6d716ca8 RS |
6151 | /* If one arg is a constant integer, put it last. */ |
6152 | if (TREE_CODE (arg0) == INTEGER_CST | |
6153 | && TREE_CODE (arg1) != INTEGER_CST) | |
6154 | { | |
6155 | TREE_OPERAND (t, 0) = arg1; | |
6156 | TREE_OPERAND (t, 1) = arg0; | |
6157 | arg0 = TREE_OPERAND (t, 0); | |
6158 | arg1 = TREE_OPERAND (t, 1); | |
c05a9b68 | 6159 | code = swap_tree_comparison (code); |
6d716ca8 RS |
6160 | TREE_SET_CODE (t, code); |
6161 | } | |
6162 | ||
6163 | /* Convert foo++ == CONST into ++foo == CONST + INCR. | |
6164 | First, see if one arg is constant; find the constant arg | |
6165 | and the other one. */ | |
6166 | { | |
4e86caed | 6167 | tree constop = 0, varop = NULL_TREE; |
cd7ece66 | 6168 | int constopnum = -1; |
6d716ca8 RS |
6169 | |
6170 | if (TREE_CONSTANT (arg1)) | |
cd7ece66 | 6171 | constopnum = 1, constop = arg1, varop = arg0; |
6d716ca8 | 6172 | if (TREE_CONSTANT (arg0)) |
cd7ece66 | 6173 | constopnum = 0, constop = arg0, varop = arg1; |
6d716ca8 RS |
6174 | |
6175 | if (constop && TREE_CODE (varop) == POSTINCREMENT_EXPR) | |
6176 | { | |
6d716ca8 RS |
6177 | /* This optimization is invalid for ordered comparisons |
6178 | if CONST+INCR overflows or if foo+incr might overflow. | |
c05a9b68 | 6179 | This optimization is invalid for floating point due to rounding. |
6d716ca8 | 6180 | For pointer types we assume overflow doesn't happen. */ |
e5e809f4 | 6181 | if (POINTER_TYPE_P (TREE_TYPE (varop)) |
7178e3af | 6182 | || (! FLOAT_TYPE_P (TREE_TYPE (varop)) |
c05a9b68 | 6183 | && (code == EQ_EXPR || code == NE_EXPR))) |
6d716ca8 | 6184 | { |
c05a9b68 RS |
6185 | tree newconst |
6186 | = fold (build (PLUS_EXPR, TREE_TYPE (varop), | |
6187 | constop, TREE_OPERAND (varop, 1))); | |
4d06bcc5 MM |
6188 | |
6189 | /* Do not overwrite the current varop to be a preincrement, | |
6190 | create a new node so that we won't confuse our caller who | |
6191 | might create trees and throw them away, reusing the | |
6192 | arguments that they passed to build. This shows up in | |
6193 | the THEN or ELSE parts of ?: being postincrements. */ | |
6194 | varop = build (PREINCREMENT_EXPR, TREE_TYPE (varop), | |
6195 | TREE_OPERAND (varop, 0), | |
6196 | TREE_OPERAND (varop, 1)); | |
cd7ece66 | 6197 | |
30eca391 RK |
6198 | /* If VAROP is a reference to a bitfield, we must mask |
6199 | the constant by the width of the field. */ | |
6200 | if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF | |
6201 | && DECL_BIT_FIELD(TREE_OPERAND | |
6202 | (TREE_OPERAND (varop, 0), 1))) | |
6203 | { | |
6204 | int size | |
6205 | = TREE_INT_CST_LOW (DECL_SIZE | |
6206 | (TREE_OPERAND | |
6207 | (TREE_OPERAND (varop, 0), 1))); | |
df0e526f | 6208 | tree mask, unsigned_type; |
770ae6cc | 6209 | unsigned int precision; |
df0e526f AS |
6210 | tree folded_compare; |
6211 | ||
6212 | /* First check whether the comparison would come out | |
6213 | always the same. If we don't do that we would | |
6214 | change the meaning with the masking. */ | |
6215 | if (constopnum == 0) | |
6216 | folded_compare = fold (build (code, type, constop, | |
6217 | TREE_OPERAND (varop, 0))); | |
6218 | else | |
6219 | folded_compare = fold (build (code, type, | |
6220 | TREE_OPERAND (varop, 0), | |
6221 | constop)); | |
6222 | if (integer_zerop (folded_compare) | |
6223 | || integer_onep (folded_compare)) | |
6224 | return omit_one_operand (type, folded_compare, varop); | |
6225 | ||
6226 | unsigned_type = type_for_size (size, 1); | |
6227 | precision = TYPE_PRECISION (unsigned_type); | |
6228 | mask = build_int_2 (~0, ~0); | |
6229 | TREE_TYPE (mask) = unsigned_type; | |
6230 | force_fit_type (mask, 0); | |
6231 | mask = const_binop (RSHIFT_EXPR, mask, | |
6232 | size_int (precision - size), 0); | |
30eca391 RK |
6233 | newconst = fold (build (BIT_AND_EXPR, |
6234 | TREE_TYPE (varop), newconst, | |
6235 | convert (TREE_TYPE (varop), | |
df0e526f | 6236 | mask))); |
30eca391 | 6237 | } |
30eca391 | 6238 | |
4d06bcc5 MM |
6239 | t = build (code, type, |
6240 | (constopnum == 0) ? newconst : varop, | |
6241 | (constopnum == 1) ? newconst : varop); | |
c05a9b68 | 6242 | return t; |
6d716ca8 RS |
6243 | } |
6244 | } | |
6245 | else if (constop && TREE_CODE (varop) == POSTDECREMENT_EXPR) | |
6246 | { | |
e5e809f4 | 6247 | if (POINTER_TYPE_P (TREE_TYPE (varop)) |
7178e3af | 6248 | || (! FLOAT_TYPE_P (TREE_TYPE (varop)) |
c05a9b68 | 6249 | && (code == EQ_EXPR || code == NE_EXPR))) |
6d716ca8 | 6250 | { |
c05a9b68 RS |
6251 | tree newconst |
6252 | = fold (build (MINUS_EXPR, TREE_TYPE (varop), | |
6253 | constop, TREE_OPERAND (varop, 1))); | |
4d06bcc5 MM |
6254 | |
6255 | /* Do not overwrite the current varop to be a predecrement, | |
6256 | create a new node so that we won't confuse our caller who | |
6257 | might create trees and throw them away, reusing the | |
6258 | arguments that they passed to build. This shows up in | |
6259 | the THEN or ELSE parts of ?: being postdecrements. */ | |
6260 | varop = build (PREDECREMENT_EXPR, TREE_TYPE (varop), | |
6261 | TREE_OPERAND (varop, 0), | |
6262 | TREE_OPERAND (varop, 1)); | |
30eca391 RK |
6263 | |
6264 | if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF | |
6265 | && DECL_BIT_FIELD(TREE_OPERAND | |
6266 | (TREE_OPERAND (varop, 0), 1))) | |
6267 | { | |
6268 | int size | |
6269 | = TREE_INT_CST_LOW (DECL_SIZE | |
6270 | (TREE_OPERAND | |
6271 | (TREE_OPERAND (varop, 0), 1))); | |
df0e526f | 6272 | tree mask, unsigned_type; |
770ae6cc | 6273 | unsigned int precision; |
df0e526f AS |
6274 | tree folded_compare; |
6275 | ||
6276 | if (constopnum == 0) | |
6277 | folded_compare = fold (build (code, type, constop, | |
6278 | TREE_OPERAND (varop, 0))); | |
6279 | else | |
6280 | folded_compare = fold (build (code, type, | |
6281 | TREE_OPERAND (varop, 0), | |
6282 | constop)); | |
6283 | if (integer_zerop (folded_compare) | |
6284 | || integer_onep (folded_compare)) | |
6285 | return omit_one_operand (type, folded_compare, varop); | |
6286 | ||
6287 | unsigned_type = type_for_size (size, 1); | |
6288 | precision = TYPE_PRECISION (unsigned_type); | |
6289 | mask = build_int_2 (~0, ~0); | |
6290 | TREE_TYPE (mask) = TREE_TYPE (varop); | |
6291 | force_fit_type (mask, 0); | |
6292 | mask = const_binop (RSHIFT_EXPR, mask, | |
6293 | size_int (precision - size), 0); | |
30eca391 RK |
6294 | newconst = fold (build (BIT_AND_EXPR, |
6295 | TREE_TYPE (varop), newconst, | |
6296 | convert (TREE_TYPE (varop), | |
df0e526f | 6297 | mask))); |
30eca391 | 6298 | } |
30eca391 | 6299 | |
4d06bcc5 MM |
6300 | t = build (code, type, |
6301 | (constopnum == 0) ? newconst : varop, | |
6302 | (constopnum == 1) ? newconst : varop); | |
c05a9b68 | 6303 | return t; |
6d716ca8 RS |
6304 | } |
6305 | } | |
6306 | } | |
6307 | ||
6308 | /* Change X >= CST to X > (CST - 1) if CST is positive. */ | |
6309 | if (TREE_CODE (arg1) == INTEGER_CST | |
6310 | && TREE_CODE (arg0) != INTEGER_CST | |
d0cb4c65 | 6311 | && tree_int_cst_sgn (arg1) > 0) |
6d716ca8 RS |
6312 | { |
6313 | switch (TREE_CODE (t)) | |
6314 | { | |
6315 | case GE_EXPR: | |
6316 | code = GT_EXPR; | |
91d33e36 | 6317 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
cd7ece66 | 6318 | t = build (code, type, TREE_OPERAND (t, 0), arg1); |
6d716ca8 RS |
6319 | break; |
6320 | ||
6321 | case LT_EXPR: | |
6322 | code = LE_EXPR; | |
91d33e36 | 6323 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
cd7ece66 RK |
6324 | t = build (code, type, TREE_OPERAND (t, 0), arg1); |
6325 | break; | |
e9a25f70 JL |
6326 | |
6327 | default: | |
6328 | break; | |
6d716ca8 RS |
6329 | } |
6330 | } | |
6331 | ||
14a774a9 RK |
6332 | /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or |
6333 | a MINUS_EXPR of a constant, we can convert it into a comparison with | |
6334 | a revised constant as long as no overflow occurs. */ | |
6335 | if ((code == EQ_EXPR || code == NE_EXPR) | |
6336 | && TREE_CODE (arg1) == INTEGER_CST | |
6337 | && (TREE_CODE (arg0) == PLUS_EXPR | |
6338 | || TREE_CODE (arg0) == MINUS_EXPR) | |
6339 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
6340 | && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR | |
6341 | ? MINUS_EXPR : PLUS_EXPR, | |
6342 | arg1, TREE_OPERAND (arg0, 1), 0)) | |
6343 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
6344 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
6345 | ||
6346 | /* Similarly for a NEGATE_EXPR. */ | |
6347 | else if ((code == EQ_EXPR || code == NE_EXPR) | |
6348 | && TREE_CODE (arg0) == NEGATE_EXPR | |
6349 | && TREE_CODE (arg1) == INTEGER_CST | |
1baa375f | 6350 | && 0 != (tem = negate_expr (arg1)) |
14a774a9 RK |
6351 | && TREE_CODE (tem) == INTEGER_CST |
6352 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
6353 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
6354 | ||
6355 | /* If we have X - Y == 0, we can convert that to X == Y and similarly | |
6356 | for !=. Don't do this for ordered comparisons due to overflow. */ | |
6357 | else if ((code == NE_EXPR || code == EQ_EXPR) | |
6358 | && integer_zerop (arg1) && TREE_CODE (arg0) == MINUS_EXPR) | |
6359 | return fold (build (code, type, | |
6360 | TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1))); | |
6361 | ||
6362 | /* If we are widening one operand of an integer comparison, | |
6363 | see if the other operand is similarly being widened. Perhaps we | |
6364 | can do the comparison in the narrower type. */ | |
6365 | else if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE | |
6366 | && TREE_CODE (arg0) == NOP_EXPR | |
6367 | && (tem = get_unwidened (arg0, NULL_TREE)) != arg0 | |
6368 | && (t1 = get_unwidened (arg1, TREE_TYPE (tem))) != 0 | |
6369 | && (TREE_TYPE (t1) == TREE_TYPE (tem) | |
6370 | || (TREE_CODE (t1) == INTEGER_CST | |
6371 | && int_fits_type_p (t1, TREE_TYPE (tem))))) | |
6372 | return fold (build (code, type, tem, convert (TREE_TYPE (tem), t1))); | |
b6cc0a72 | 6373 | |
14a774a9 RK |
6374 | /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a |
6375 | constant, we can simplify it. */ | |
6376 | else if (TREE_CODE (arg1) == INTEGER_CST | |
6377 | && (TREE_CODE (arg0) == MIN_EXPR | |
6378 | || TREE_CODE (arg0) == MAX_EXPR) | |
6379 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
6380 | return optimize_minmax_comparison (t); | |
6381 | ||
6382 | /* If we are comparing an ABS_EXPR with a constant, we can | |
6383 | convert all the cases into explicit comparisons, but they may | |
6384 | well not be faster than doing the ABS and one comparison. | |
6385 | But ABS (X) <= C is a range comparison, which becomes a subtraction | |
6386 | and a comparison, and is probably faster. */ | |
6387 | else if (code == LE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
6388 | && TREE_CODE (arg0) == ABS_EXPR | |
1baa375f RK |
6389 | && ! TREE_SIDE_EFFECTS (arg0) |
6390 | && (0 != (tem = negate_expr (arg1))) | |
6391 | && TREE_CODE (tem) == INTEGER_CST | |
6392 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
6393 | return fold (build (TRUTH_ANDIF_EXPR, type, | |
6394 | build (GE_EXPR, type, TREE_OPERAND (arg0, 0), tem), | |
6395 | build (LE_EXPR, type, | |
6396 | TREE_OPERAND (arg0, 0), arg1))); | |
b6cc0a72 | 6397 | |
6d716ca8 RS |
6398 | /* If this is an EQ or NE comparison with zero and ARG0 is |
6399 | (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require | |
6400 | two operations, but the latter can be done in one less insn | |
e9a25f70 | 6401 | on machines that have only two-operand insns or on which a |
6d716ca8 RS |
6402 | constant cannot be the first operand. */ |
6403 | if (integer_zerop (arg1) && (code == EQ_EXPR || code == NE_EXPR) | |
6404 | && TREE_CODE (arg0) == BIT_AND_EXPR) | |
6405 | { | |
6406 | if (TREE_CODE (TREE_OPERAND (arg0, 0)) == LSHIFT_EXPR | |
6407 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 0), 0))) | |
6408 | return | |
6409 | fold (build (code, type, | |
6410 | build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
6411 | build (RSHIFT_EXPR, | |
6412 | TREE_TYPE (TREE_OPERAND (arg0, 0)), | |
6413 | TREE_OPERAND (arg0, 1), | |
6414 | TREE_OPERAND (TREE_OPERAND (arg0, 0), 1)), | |
6415 | convert (TREE_TYPE (arg0), | |
6416 | integer_one_node)), | |
6417 | arg1)); | |
6418 | else if (TREE_CODE (TREE_OPERAND (arg0, 1)) == LSHIFT_EXPR | |
6419 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 1), 0))) | |
6420 | return | |
6421 | fold (build (code, type, | |
6422 | build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
6423 | build (RSHIFT_EXPR, | |
6424 | TREE_TYPE (TREE_OPERAND (arg0, 1)), | |
6425 | TREE_OPERAND (arg0, 0), | |
6426 | TREE_OPERAND (TREE_OPERAND (arg0, 1), 1)), | |
6427 | convert (TREE_TYPE (arg0), | |
6428 | integer_one_node)), | |
6429 | arg1)); | |
6430 | } | |
6431 | ||
05a0d5ea | 6432 | /* If this is an NE or EQ comparison of zero against the result of a |
79bf94d3 RK |
6433 | signed MOD operation whose second operand is a power of 2, make |
6434 | the MOD operation unsigned since it is simpler and equivalent. */ | |
05a0d5ea RK |
6435 | if ((code == NE_EXPR || code == EQ_EXPR) |
6436 | && integer_zerop (arg1) | |
6437 | && ! TREE_UNSIGNED (TREE_TYPE (arg0)) | |
6438 | && (TREE_CODE (arg0) == TRUNC_MOD_EXPR | |
6439 | || TREE_CODE (arg0) == CEIL_MOD_EXPR | |
6440 | || TREE_CODE (arg0) == FLOOR_MOD_EXPR | |
79bf94d3 RK |
6441 | || TREE_CODE (arg0) == ROUND_MOD_EXPR) |
6442 | && integer_pow2p (TREE_OPERAND (arg0, 1))) | |
05a0d5ea RK |
6443 | { |
6444 | tree newtype = unsigned_type (TREE_TYPE (arg0)); | |
6445 | tree newmod = build (TREE_CODE (arg0), newtype, | |
6446 | convert (newtype, TREE_OPERAND (arg0, 0)), | |
6447 | convert (newtype, TREE_OPERAND (arg0, 1))); | |
6448 | ||
6449 | return build (code, type, newmod, convert (newtype, arg1)); | |
6450 | } | |
6451 | ||
6d716ca8 RS |
6452 | /* If this is an NE comparison of zero with an AND of one, remove the |
6453 | comparison since the AND will give the correct value. */ | |
6454 | if (code == NE_EXPR && integer_zerop (arg1) | |
6455 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
6456 | && integer_onep (TREE_OPERAND (arg0, 1))) | |
6457 | return convert (type, arg0); | |
6458 | ||
6459 | /* If we have (A & C) == C where C is a power of 2, convert this into | |
6460 | (A & C) != 0. Similarly for NE_EXPR. */ | |
6461 | if ((code == EQ_EXPR || code == NE_EXPR) | |
6462 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
6463 | && integer_pow2p (TREE_OPERAND (arg0, 1)) | |
6464 | && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)) | |
6465 | return build (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type, | |
6466 | arg0, integer_zero_node); | |
6467 | ||
e92d3048 | 6468 | /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0 |
34b1b41f | 6469 | and similarly for >= into !=. */ |
e92d3048 RK |
6470 | if ((code == LT_EXPR || code == GE_EXPR) |
6471 | && TREE_UNSIGNED (TREE_TYPE (arg0)) | |
6472 | && TREE_CODE (arg1) == LSHIFT_EXPR | |
6473 | && integer_onep (TREE_OPERAND (arg1, 0))) | |
b6cc0a72 | 6474 | return build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type, |
e92d3048 RK |
6475 | build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0, |
6476 | TREE_OPERAND (arg1, 1)), | |
6477 | convert (TREE_TYPE (arg0), integer_zero_node)); | |
6478 | ||
6479 | else if ((code == LT_EXPR || code == GE_EXPR) | |
6480 | && TREE_UNSIGNED (TREE_TYPE (arg0)) | |
6481 | && (TREE_CODE (arg1) == NOP_EXPR | |
6482 | || TREE_CODE (arg1) == CONVERT_EXPR) | |
6483 | && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR | |
6484 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0))) | |
6485 | return | |
6486 | build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type, | |
6487 | convert (TREE_TYPE (arg0), | |
6488 | build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0, | |
6489 | TREE_OPERAND (TREE_OPERAND (arg1, 0), 1))), | |
6490 | convert (TREE_TYPE (arg0), integer_zero_node)); | |
6491 | ||
c05a9b68 RS |
6492 | /* Simplify comparison of something with itself. (For IEEE |
6493 | floating-point, we can only do some of these simplifications.) */ | |
6494 | if (operand_equal_p (arg0, arg1, 0)) | |
6d716ca8 RS |
6495 | { |
6496 | switch (code) | |
6497 | { | |
6498 | case EQ_EXPR: | |
6499 | case GE_EXPR: | |
6500 | case LE_EXPR: | |
7178e3af | 6501 | if (INTEGRAL_TYPE_P (TREE_TYPE (arg0))) |
f628873f | 6502 | return constant_boolean_node (1, type); |
c05a9b68 RS |
6503 | code = EQ_EXPR; |
6504 | TREE_SET_CODE (t, code); | |
6505 | break; | |
6506 | ||
6d716ca8 | 6507 | case NE_EXPR: |
c05a9b68 | 6508 | /* For NE, we can only do this simplification if integer. */ |
7178e3af | 6509 | if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0))) |
c05a9b68 | 6510 | break; |
0f41302f | 6511 | /* ... fall through ... */ |
6d716ca8 RS |
6512 | case GT_EXPR: |
6513 | case LT_EXPR: | |
f628873f | 6514 | return constant_boolean_node (0, type); |
e9a25f70 JL |
6515 | default: |
6516 | abort (); | |
6d716ca8 RS |
6517 | } |
6518 | } | |
6519 | ||
6520 | /* An unsigned comparison against 0 can be simplified. */ | |
6521 | if (integer_zerop (arg1) | |
7178e3af | 6522 | && (INTEGRAL_TYPE_P (TREE_TYPE (arg1)) |
e5e809f4 | 6523 | || POINTER_TYPE_P (TREE_TYPE (arg1))) |
6d716ca8 RS |
6524 | && TREE_UNSIGNED (TREE_TYPE (arg1))) |
6525 | { | |
6526 | switch (TREE_CODE (t)) | |
6527 | { | |
6528 | case GT_EXPR: | |
c05a9b68 | 6529 | code = NE_EXPR; |
6d716ca8 RS |
6530 | TREE_SET_CODE (t, NE_EXPR); |
6531 | break; | |
6532 | case LE_EXPR: | |
c05a9b68 | 6533 | code = EQ_EXPR; |
6d716ca8 RS |
6534 | TREE_SET_CODE (t, EQ_EXPR); |
6535 | break; | |
6536 | case GE_EXPR: | |
56f8e5e6 RK |
6537 | return omit_one_operand (type, |
6538 | convert (type, integer_one_node), | |
6539 | arg0); | |
6d716ca8 | 6540 | case LT_EXPR: |
56f8e5e6 RK |
6541 | return omit_one_operand (type, |
6542 | convert (type, integer_zero_node), | |
6543 | arg0); | |
e9a25f70 JL |
6544 | default: |
6545 | break; | |
6d716ca8 RS |
6546 | } |
6547 | } | |
6548 | ||
14a774a9 RK |
6549 | /* Comparisons with the highest or lowest possible integer of |
6550 | the specified size will have known values and an unsigned | |
6551 | <= 0x7fffffff can be simplified. */ | |
e9a25f70 | 6552 | { |
14a774a9 RK |
6553 | int width = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg1))); |
6554 | ||
e9a25f70 JL |
6555 | if (TREE_CODE (arg1) == INTEGER_CST |
6556 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
6557 | && width <= HOST_BITS_PER_WIDE_INT | |
e9a25f70 | 6558 | && (INTEGRAL_TYPE_P (TREE_TYPE (arg1)) |
14a774a9 | 6559 | || POINTER_TYPE_P (TREE_TYPE (arg1)))) |
e9a25f70 | 6560 | { |
14a774a9 RK |
6561 | if (TREE_INT_CST_HIGH (arg1) == 0 |
6562 | && (TREE_INT_CST_LOW (arg1) | |
05bccae2 | 6563 | == ((unsigned HOST_WIDE_INT) 1 << (width - 1)) - 1) |
14a774a9 RK |
6564 | && ! TREE_UNSIGNED (TREE_TYPE (arg1))) |
6565 | switch (TREE_CODE (t)) | |
6566 | { | |
6567 | case GT_EXPR: | |
6568 | return omit_one_operand (type, | |
6569 | convert (type, integer_zero_node), | |
6570 | arg0); | |
6571 | case GE_EXPR: | |
6572 | TREE_SET_CODE (t, EQ_EXPR); | |
6573 | break; | |
6574 | ||
6575 | case LE_EXPR: | |
6576 | return omit_one_operand (type, | |
6577 | convert (type, integer_one_node), | |
6578 | arg0); | |
6579 | case LT_EXPR: | |
6580 | TREE_SET_CODE (t, NE_EXPR); | |
6581 | break; | |
6582 | ||
6583 | default: | |
6584 | break; | |
6585 | } | |
6586 | ||
6587 | else if (TREE_INT_CST_HIGH (arg1) == -1 | |
6588 | && (- TREE_INT_CST_LOW (arg1) | |
05bccae2 | 6589 | == ((unsigned HOST_WIDE_INT) 1 << (width - 1))) |
14a774a9 RK |
6590 | && ! TREE_UNSIGNED (TREE_TYPE (arg1))) |
6591 | switch (TREE_CODE (t)) | |
6592 | { | |
6593 | case LT_EXPR: | |
6594 | return omit_one_operand (type, | |
6595 | convert (type, integer_zero_node), | |
6596 | arg0); | |
6597 | case LE_EXPR: | |
6598 | TREE_SET_CODE (t, EQ_EXPR); | |
6599 | break; | |
6600 | ||
6601 | case GE_EXPR: | |
6602 | return omit_one_operand (type, | |
6603 | convert (type, integer_one_node), | |
6604 | arg0); | |
6605 | case GT_EXPR: | |
6606 | TREE_SET_CODE (t, NE_EXPR); | |
6607 | break; | |
6608 | ||
6609 | default: | |
6610 | break; | |
6611 | } | |
6612 | ||
6613 | else if (TREE_INT_CST_HIGH (arg1) == 0 | |
6614 | && (TREE_INT_CST_LOW (arg1) | |
05bccae2 | 6615 | == ((unsigned HOST_WIDE_INT) 1 << (width - 1)) - 1) |
d791ea1e JJ |
6616 | && TREE_UNSIGNED (TREE_TYPE (arg1)) |
6617 | /* signed_type does not work on pointer types. */ | |
6618 | && INTEGRAL_TYPE_P (TREE_TYPE (arg1))) | |
b6cc0a72 | 6619 | |
14a774a9 RK |
6620 | switch (TREE_CODE (t)) |
6621 | { | |
6622 | case LE_EXPR: | |
6623 | return fold (build (GE_EXPR, type, | |
6624 | convert (signed_type (TREE_TYPE (arg0)), | |
6625 | arg0), | |
6626 | convert (signed_type (TREE_TYPE (arg1)), | |
6627 | integer_zero_node))); | |
6628 | case GT_EXPR: | |
6629 | return fold (build (LT_EXPR, type, | |
6630 | convert (signed_type (TREE_TYPE (arg0)), | |
6631 | arg0), | |
6632 | convert (signed_type (TREE_TYPE (arg1)), | |
6633 | integer_zero_node))); | |
6634 | ||
6635 | default: | |
6636 | break; | |
6637 | } | |
e9a25f70 JL |
6638 | } |
6639 | } | |
6640 | ||
c05a9b68 RS |
6641 | /* If we are comparing an expression that just has comparisons |
6642 | of two integer values, arithmetic expressions of those comparisons, | |
6643 | and constants, we can simplify it. There are only three cases | |
6644 | to check: the two values can either be equal, the first can be | |
6645 | greater, or the second can be greater. Fold the expression for | |
6646 | those three values. Since each value must be 0 or 1, we have | |
6647 | eight possibilities, each of which corresponds to the constant 0 | |
6648 | or 1 or one of the six possible comparisons. | |
6649 | ||
6650 | This handles common cases like (a > b) == 0 but also handles | |
6651 | expressions like ((x > y) - (y > x)) > 0, which supposedly | |
6652 | occur in macroized code. */ | |
6653 | ||
6654 | if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST) | |
6655 | { | |
6656 | tree cval1 = 0, cval2 = 0; | |
35e66bd1 | 6657 | int save_p = 0; |
c05a9b68 | 6658 | |
35e66bd1 | 6659 | if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p) |
c05a9b68 RS |
6660 | /* Don't handle degenerate cases here; they should already |
6661 | have been handled anyway. */ | |
6662 | && cval1 != 0 && cval2 != 0 | |
6663 | && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2)) | |
6664 | && TREE_TYPE (cval1) == TREE_TYPE (cval2) | |
7178e3af | 6665 | && INTEGRAL_TYPE_P (TREE_TYPE (cval1)) |
e1ee5cdc RH |
6666 | && TYPE_MAX_VALUE (TREE_TYPE (cval1)) |
6667 | && TYPE_MAX_VALUE (TREE_TYPE (cval2)) | |
c05a9b68 RS |
6668 | && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)), |
6669 | TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0)) | |
6670 | { | |
6671 | tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1)); | |
6672 | tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1)); | |
6673 | ||
6674 | /* We can't just pass T to eval_subst in case cval1 or cval2 | |
6675 | was the same as ARG1. */ | |
6676 | ||
6677 | tree high_result | |
6678 | = fold (build (code, type, | |
6679 | eval_subst (arg0, cval1, maxval, cval2, minval), | |
6680 | arg1)); | |
6681 | tree equal_result | |
6682 | = fold (build (code, type, | |
6683 | eval_subst (arg0, cval1, maxval, cval2, maxval), | |
6684 | arg1)); | |
6685 | tree low_result | |
6686 | = fold (build (code, type, | |
6687 | eval_subst (arg0, cval1, minval, cval2, maxval), | |
6688 | arg1)); | |
6689 | ||
6690 | /* All three of these results should be 0 or 1. Confirm they | |
6691 | are. Then use those values to select the proper code | |
6692 | to use. */ | |
6693 | ||
6694 | if ((integer_zerop (high_result) | |
6695 | || integer_onep (high_result)) | |
6696 | && (integer_zerop (equal_result) | |
6697 | || integer_onep (equal_result)) | |
6698 | && (integer_zerop (low_result) | |
6699 | || integer_onep (low_result))) | |
6700 | { | |
6701 | /* Make a 3-bit mask with the high-order bit being the | |
6702 | value for `>', the next for '=', and the low for '<'. */ | |
6703 | switch ((integer_onep (high_result) * 4) | |
6704 | + (integer_onep (equal_result) * 2) | |
6705 | + integer_onep (low_result)) | |
6706 | { | |
6707 | case 0: | |
6708 | /* Always false. */ | |
13837058 | 6709 | return omit_one_operand (type, integer_zero_node, arg0); |
c05a9b68 RS |
6710 | case 1: |
6711 | code = LT_EXPR; | |
6712 | break; | |
6713 | case 2: | |
6714 | code = EQ_EXPR; | |
6715 | break; | |
6716 | case 3: | |
6717 | code = LE_EXPR; | |
6718 | break; | |
6719 | case 4: | |
6720 | code = GT_EXPR; | |
6721 | break; | |
6722 | case 5: | |
6723 | code = NE_EXPR; | |
6724 | break; | |
6725 | case 6: | |
6726 | code = GE_EXPR; | |
6727 | break; | |
6728 | case 7: | |
6729 | /* Always true. */ | |
13837058 | 6730 | return omit_one_operand (type, integer_one_node, arg0); |
c05a9b68 RS |
6731 | } |
6732 | ||
35e66bd1 RK |
6733 | t = build (code, type, cval1, cval2); |
6734 | if (save_p) | |
6735 | return save_expr (t); | |
6736 | else | |
6737 | return fold (t); | |
c05a9b68 RS |
6738 | } |
6739 | } | |
6740 | } | |
6741 | ||
6742 | /* If this is a comparison of a field, we may be able to simplify it. */ | |
9c922ec7 MM |
6743 | if ((TREE_CODE (arg0) == COMPONENT_REF |
6744 | || TREE_CODE (arg0) == BIT_FIELD_REF) | |
6745 | && (code == EQ_EXPR || code == NE_EXPR) | |
6746 | /* Handle the constant case even without -O | |
6747 | to make sure the warnings are given. */ | |
6748 | && (optimize || TREE_CODE (arg1) == INTEGER_CST)) | |
6749 | { | |
6750 | t1 = optimize_bit_field_compare (code, type, arg0, arg1); | |
6751 | return t1 ? t1 : t; | |
6752 | } | |
c05a9b68 | 6753 | |
9ec36da5 JL |
6754 | /* If this is a comparison of complex values and either or both sides |
6755 | are a COMPLEX_EXPR or COMPLEX_CST, it is best to split up the | |
6756 | comparisons and join them with a TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR. | |
6757 | This may prevent needless evaluations. */ | |
95aa28ae RK |
6758 | if ((code == EQ_EXPR || code == NE_EXPR) |
6759 | && TREE_CODE (TREE_TYPE (arg0)) == COMPLEX_TYPE | |
6760 | && (TREE_CODE (arg0) == COMPLEX_EXPR | |
9ec36da5 JL |
6761 | || TREE_CODE (arg1) == COMPLEX_EXPR |
6762 | || TREE_CODE (arg0) == COMPLEX_CST | |
6763 | || TREE_CODE (arg1) == COMPLEX_CST)) | |
95aa28ae RK |
6764 | { |
6765 | tree subtype = TREE_TYPE (TREE_TYPE (arg0)); | |
f0b8d9aa AS |
6766 | tree real0, imag0, real1, imag1; |
6767 | ||
6768 | arg0 = save_expr (arg0); | |
6769 | arg1 = save_expr (arg1); | |
6770 | real0 = fold (build1 (REALPART_EXPR, subtype, arg0)); | |
6771 | imag0 = fold (build1 (IMAGPART_EXPR, subtype, arg0)); | |
6772 | real1 = fold (build1 (REALPART_EXPR, subtype, arg1)); | |
6773 | imag1 = fold (build1 (IMAGPART_EXPR, subtype, arg1)); | |
95aa28ae RK |
6774 | |
6775 | return fold (build ((code == EQ_EXPR ? TRUTH_ANDIF_EXPR | |
6776 | : TRUTH_ORIF_EXPR), | |
6777 | type, | |
6778 | fold (build (code, type, real0, real1)), | |
6779 | fold (build (code, type, imag0, imag1)))); | |
6780 | } | |
6781 | ||
c05a9b68 RS |
6782 | /* From here on, the only cases we handle are when the result is |
6783 | known to be a constant. | |
6784 | ||
6785 | To compute GT, swap the arguments and do LT. | |
6d716ca8 RS |
6786 | To compute GE, do LT and invert the result. |
6787 | To compute LE, swap the arguments, do LT and invert the result. | |
c05a9b68 RS |
6788 | To compute NE, do EQ and invert the result. |
6789 | ||
6790 | Therefore, the code below must handle only EQ and LT. */ | |
6791 | ||
6d716ca8 RS |
6792 | if (code == LE_EXPR || code == GT_EXPR) |
6793 | { | |
c05a9b68 RS |
6794 | tem = arg0, arg0 = arg1, arg1 = tem; |
6795 | code = swap_tree_comparison (code); | |
6796 | } | |
6797 | ||
6798 | /* Note that it is safe to invert for real values here because we | |
6799 | will check below in the one case that it matters. */ | |
6800 | ||
14a774a9 | 6801 | t1 = NULL_TREE; |
c05a9b68 RS |
6802 | invert = 0; |
6803 | if (code == NE_EXPR || code == GE_EXPR) | |
6804 | { | |
6805 | invert = 1; | |
6806 | code = invert_tree_comparison (code); | |
6d716ca8 RS |
6807 | } |
6808 | ||
6809 | /* Compute a result for LT or EQ if args permit; | |
6810 | otherwise return T. */ | |
c05a9b68 | 6811 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) |
6d716ca8 | 6812 | { |
c05a9b68 | 6813 | if (code == EQ_EXPR) |
05bccae2 | 6814 | t1 = build_int_2 (tree_int_cst_equal (arg0, arg1), 0); |
6d716ca8 | 6815 | else |
c05a9b68 RS |
6816 | t1 = build_int_2 ((TREE_UNSIGNED (TREE_TYPE (arg0)) |
6817 | ? INT_CST_LT_UNSIGNED (arg0, arg1) | |
6818 | : INT_CST_LT (arg0, arg1)), | |
6819 | 0); | |
6d716ca8 | 6820 | } |
c05a9b68 | 6821 | |
e80c9ccb | 6822 | #if 0 /* This is no longer useful, but breaks some real code. */ |
6d716ca8 RS |
6823 | /* Assume a nonexplicit constant cannot equal an explicit one, |
6824 | since such code would be undefined anyway. | |
6825 | Exception: on sysvr4, using #pragma weak, | |
6826 | a label can come out as 0. */ | |
6827 | else if (TREE_CODE (arg1) == INTEGER_CST | |
6828 | && !integer_zerop (arg1) | |
6829 | && TREE_CONSTANT (arg0) | |
6830 | && TREE_CODE (arg0) == ADDR_EXPR | |
c05a9b68 RS |
6831 | && code == EQ_EXPR) |
6832 | t1 = build_int_2 (0, 0); | |
e80c9ccb | 6833 | #endif |
6d716ca8 | 6834 | /* Two real constants can be compared explicitly. */ |
c05a9b68 | 6835 | else if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST) |
6d716ca8 | 6836 | { |
c05a9b68 RS |
6837 | /* If either operand is a NaN, the result is false with two |
6838 | exceptions: First, an NE_EXPR is true on NaNs, but that case | |
6839 | is already handled correctly since we will be inverting the | |
6840 | result for NE_EXPR. Second, if we had inverted a LE_EXPR | |
6841 | or a GE_EXPR into a LT_EXPR, we must return true so that it | |
6842 | will be inverted into false. */ | |
6843 | ||
6844 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg0)) | |
6845 | || REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))) | |
6846 | t1 = build_int_2 (invert && code == LT_EXPR, 0); | |
6847 | ||
6848 | else if (code == EQ_EXPR) | |
6849 | t1 = build_int_2 (REAL_VALUES_EQUAL (TREE_REAL_CST (arg0), | |
6850 | TREE_REAL_CST (arg1)), | |
6851 | 0); | |
6d716ca8 | 6852 | else |
c05a9b68 RS |
6853 | t1 = build_int_2 (REAL_VALUES_LESS (TREE_REAL_CST (arg0), |
6854 | TREE_REAL_CST (arg1)), | |
6855 | 0); | |
6d716ca8 RS |
6856 | } |
6857 | ||
c05a9b68 RS |
6858 | if (t1 == NULL_TREE) |
6859 | return t; | |
6860 | ||
6861 | if (invert) | |
6862 | TREE_INT_CST_LOW (t1) ^= 1; | |
6863 | ||
6864 | TREE_TYPE (t1) = type; | |
c651e1e0 MM |
6865 | if (TREE_CODE (type) == BOOLEAN_TYPE) |
6866 | return truthvalue_conversion (t1); | |
c05a9b68 | 6867 | return t1; |
6d716ca8 RS |
6868 | |
6869 | case COND_EXPR: | |
a5e9b124 JW |
6870 | /* Pedantic ANSI C says that a conditional expression is never an lvalue, |
6871 | so all simple results must be passed through pedantic_non_lvalue. */ | |
6d716ca8 | 6872 | if (TREE_CODE (arg0) == INTEGER_CST) |
a5e9b124 JW |
6873 | return pedantic_non_lvalue |
6874 | (TREE_OPERAND (t, (integer_zerop (arg0) ? 2 : 1))); | |
6d716ca8 | 6875 | else if (operand_equal_p (arg1, TREE_OPERAND (expr, 2), 0)) |
4ab3cb65 | 6876 | return pedantic_omit_one_operand (type, arg1, arg0); |
6d716ca8 | 6877 | |
c05a9b68 RS |
6878 | /* If the second operand is zero, invert the comparison and swap |
6879 | the second and third operands. Likewise if the second operand | |
6880 | is constant and the third is not or if the third operand is | |
6881 | equivalent to the first operand of the comparison. */ | |
6d716ca8 | 6882 | |
c05a9b68 RS |
6883 | if (integer_zerop (arg1) |
6884 | || (TREE_CONSTANT (arg1) && ! TREE_CONSTANT (TREE_OPERAND (t, 2))) | |
6885 | || (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' | |
6886 | && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0), | |
6887 | TREE_OPERAND (t, 2), | |
6888 | TREE_OPERAND (arg0, 1)))) | |
6889 | { | |
6890 | /* See if this can be inverted. If it can't, possibly because | |
6891 | it was a floating-point inequality comparison, don't do | |
6892 | anything. */ | |
6893 | tem = invert_truthvalue (arg0); | |
6d716ca8 | 6894 | |
c05a9b68 RS |
6895 | if (TREE_CODE (tem) != TRUTH_NOT_EXPR) |
6896 | { | |
cd7ece66 RK |
6897 | t = build (code, type, tem, |
6898 | TREE_OPERAND (t, 2), TREE_OPERAND (t, 1)); | |
6899 | arg0 = tem; | |
a58bd508 MT |
6900 | /* arg1 should be the first argument of the new T. */ |
6901 | arg1 = TREE_OPERAND (t, 1); | |
3a96b5eb | 6902 | STRIP_NOPS (arg1); |
c05a9b68 RS |
6903 | } |
6904 | } | |
6d716ca8 | 6905 | |
c05a9b68 RS |
6906 | /* If we have A op B ? A : C, we may be able to convert this to a |
6907 | simpler expression, depending on the operation and the values | |
b5c52586 RS |
6908 | of B and C. IEEE floating point prevents this though, |
6909 | because A or B might be -0.0 or a NaN. */ | |
6d716ca8 | 6910 | |
c05a9b68 | 6911 | if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' |
b5c52586 | 6912 | && (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
fab446b8 | 6913 | || ! FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 0))) |
de6c5979 | 6914 | || flag_unsafe_math_optimizations) |
c05a9b68 RS |
6915 | && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0), |
6916 | arg1, TREE_OPERAND (arg0, 1))) | |
6d716ca8 | 6917 | { |
c05a9b68 RS |
6918 | tree arg2 = TREE_OPERAND (t, 2); |
6919 | enum tree_code comp_code = TREE_CODE (arg0); | |
6920 | ||
3a96b5eb RK |
6921 | STRIP_NOPS (arg2); |
6922 | ||
c05a9b68 RS |
6923 | /* If we have A op 0 ? A : -A, this is A, -A, abs (A), or abs (-A), |
6924 | depending on the comparison operation. */ | |
68c6b3a9 DE |
6925 | if ((FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 1))) |
6926 | ? real_zerop (TREE_OPERAND (arg0, 1)) | |
6927 | : integer_zerop (TREE_OPERAND (arg0, 1))) | |
c05a9b68 RS |
6928 | && TREE_CODE (arg2) == NEGATE_EXPR |
6929 | && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0)) | |
6930 | switch (comp_code) | |
6931 | { | |
6932 | case EQ_EXPR: | |
c9869b75 | 6933 | return |
b8fbe62c RK |
6934 | pedantic_non_lvalue |
6935 | (convert (type, | |
6936 | negate_expr | |
6937 | (convert (TREE_TYPE (TREE_OPERAND (t, 1)), | |
6938 | arg1)))); | |
6939 | ||
c05a9b68 | 6940 | case NE_EXPR: |
a5e9b124 | 6941 | return pedantic_non_lvalue (convert (type, arg1)); |
c05a9b68 RS |
6942 | case GE_EXPR: |
6943 | case GT_EXPR: | |
899f1ed6 RH |
6944 | if (TREE_UNSIGNED (TREE_TYPE (arg1))) |
6945 | arg1 = convert (signed_type (TREE_TYPE (arg1)), arg1); | |
a5e9b124 | 6946 | return pedantic_non_lvalue |
21403f14 RK |
6947 | (convert (type, fold (build1 (ABS_EXPR, |
6948 | TREE_TYPE (arg1), arg1)))); | |
c05a9b68 RS |
6949 | case LE_EXPR: |
6950 | case LT_EXPR: | |
899f1ed6 RH |
6951 | if (TREE_UNSIGNED (TREE_TYPE (arg1))) |
6952 | arg1 = convert (signed_type (TREE_TYPE (arg1)), arg1); | |
a5e9b124 | 6953 | return pedantic_non_lvalue |
1baa375f RK |
6954 | (negate_expr (convert (type, |
6955 | fold (build1 (ABS_EXPR, | |
6956 | TREE_TYPE (arg1), | |
6957 | arg1))))); | |
e9a25f70 JL |
6958 | default: |
6959 | abort (); | |
c05a9b68 | 6960 | } |
6d716ca8 | 6961 | |
c05a9b68 RS |
6962 | /* If this is A != 0 ? A : 0, this is simply A. For ==, it is |
6963 | always zero. */ | |
6d716ca8 | 6964 | |
29ebe69a | 6965 | if (integer_zerop (TREE_OPERAND (arg0, 1)) && integer_zerop (arg2)) |
c05a9b68 RS |
6966 | { |
6967 | if (comp_code == NE_EXPR) | |
a5e9b124 | 6968 | return pedantic_non_lvalue (convert (type, arg1)); |
c05a9b68 | 6969 | else if (comp_code == EQ_EXPR) |
a5e9b124 | 6970 | return pedantic_non_lvalue (convert (type, integer_zero_node)); |
c05a9b68 RS |
6971 | } |
6972 | ||
6973 | /* If this is A op B ? A : B, this is either A, B, min (A, B), | |
6974 | or max (A, B), depending on the operation. */ | |
6975 | ||
6976 | if (operand_equal_for_comparison_p (TREE_OPERAND (arg0, 1), | |
6977 | arg2, TREE_OPERAND (arg0, 0))) | |
3a96b5eb RK |
6978 | { |
6979 | tree comp_op0 = TREE_OPERAND (arg0, 0); | |
6980 | tree comp_op1 = TREE_OPERAND (arg0, 1); | |
6981 | tree comp_type = TREE_TYPE (comp_op0); | |
6982 | ||
a7833bec JM |
6983 | /* Avoid adding NOP_EXPRs in case this is an lvalue. */ |
6984 | if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type)) | |
6985 | comp_type = type; | |
6986 | ||
3a96b5eb RK |
6987 | switch (comp_code) |
6988 | { | |
6989 | case EQ_EXPR: | |
6990 | return pedantic_non_lvalue (convert (type, arg2)); | |
6991 | case NE_EXPR: | |
6992 | return pedantic_non_lvalue (convert (type, arg1)); | |
6993 | case LE_EXPR: | |
6994 | case LT_EXPR: | |
e9a25f70 JL |
6995 | /* In C++ a ?: expression can be an lvalue, so put the |
6996 | operand which will be used if they are equal first | |
b6cc0a72 | 6997 | so that we can convert this back to the |
e9a25f70 JL |
6998 | corresponding COND_EXPR. */ |
6999 | return pedantic_non_lvalue | |
792a328b JM |
7000 | (convert (type, fold (build (MIN_EXPR, comp_type, |
7001 | (comp_code == LE_EXPR | |
7002 | ? comp_op0 : comp_op1), | |
7003 | (comp_code == LE_EXPR | |
7004 | ? comp_op1 : comp_op0))))); | |
88a5cdb8 | 7005 | break; |
3a96b5eb RK |
7006 | case GE_EXPR: |
7007 | case GT_EXPR: | |
e9a25f70 JL |
7008 | return pedantic_non_lvalue |
7009 | (convert (type, fold (build (MAX_EXPR, comp_type, | |
7010 | (comp_code == GE_EXPR | |
7011 | ? comp_op0 : comp_op1), | |
7012 | (comp_code == GE_EXPR | |
7013 | ? comp_op1 : comp_op0))))); | |
88a5cdb8 | 7014 | break; |
e9a25f70 JL |
7015 | default: |
7016 | abort (); | |
3a96b5eb RK |
7017 | } |
7018 | } | |
c05a9b68 RS |
7019 | |
7020 | /* If this is A op C1 ? A : C2 with C1 and C2 constant integers, | |
7021 | we might still be able to simplify this. For example, | |
7022 | if C1 is one less or one more than C2, this might have started | |
53d2fb4f | 7023 | out as a MIN or MAX and been transformed by this function. |
7178e3af | 7024 | Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */ |
c05a9b68 | 7025 | |
7178e3af | 7026 | if (INTEGRAL_TYPE_P (type) |
53d2fb4f | 7027 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST |
c05a9b68 RS |
7028 | && TREE_CODE (arg2) == INTEGER_CST) |
7029 | switch (comp_code) | |
7030 | { | |
7031 | case EQ_EXPR: | |
7032 | /* We can replace A with C1 in this case. */ | |
cd7ece66 RK |
7033 | arg1 = convert (type, TREE_OPERAND (arg0, 1)); |
7034 | t = build (code, type, TREE_OPERAND (t, 0), arg1, | |
7035 | TREE_OPERAND (t, 2)); | |
c05a9b68 RS |
7036 | break; |
7037 | ||
7038 | case LT_EXPR: | |
7039 | /* If C1 is C2 + 1, this is min(A, C2). */ | |
7040 | if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), 1) | |
7041 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
7042 | const_binop (PLUS_EXPR, arg2, | |
91d33e36 | 7043 | integer_one_node, 0), 1)) |
a5e9b124 JW |
7044 | return pedantic_non_lvalue |
7045 | (fold (build (MIN_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
7046 | break; |
7047 | ||
7048 | case LE_EXPR: | |
7049 | /* If C1 is C2 - 1, this is min(A, C2). */ | |
7050 | if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), 1) | |
7051 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
7052 | const_binop (MINUS_EXPR, arg2, | |
91d33e36 | 7053 | integer_one_node, 0), 1)) |
a5e9b124 JW |
7054 | return pedantic_non_lvalue |
7055 | (fold (build (MIN_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
7056 | break; |
7057 | ||
7058 | case GT_EXPR: | |
7059 | /* If C1 is C2 - 1, this is max(A, C2). */ | |
7060 | if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), 1) | |
7061 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
7062 | const_binop (MINUS_EXPR, arg2, | |
91d33e36 | 7063 | integer_one_node, 0), 1)) |
a5e9b124 JW |
7064 | return pedantic_non_lvalue |
7065 | (fold (build (MAX_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
7066 | break; |
7067 | ||
7068 | case GE_EXPR: | |
7069 | /* If C1 is C2 + 1, this is max(A, C2). */ | |
7070 | if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), 1) | |
7071 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
7072 | const_binop (PLUS_EXPR, arg2, | |
91d33e36 | 7073 | integer_one_node, 0), 1)) |
a5e9b124 JW |
7074 | return pedantic_non_lvalue |
7075 | (fold (build (MAX_EXPR, type, arg1, arg2))); | |
c05a9b68 | 7076 | break; |
e9a25f70 JL |
7077 | case NE_EXPR: |
7078 | break; | |
7079 | default: | |
7080 | abort (); | |
c05a9b68 | 7081 | } |
6d716ca8 RS |
7082 | } |
7083 | ||
e1f56f62 RK |
7084 | /* If the second operand is simpler than the third, swap them |
7085 | since that produces better jump optimization results. */ | |
2f939d94 | 7086 | if ((TREE_CONSTANT (arg1) || DECL_P (arg1) |
e1f56f62 RK |
7087 | || TREE_CODE (arg1) == SAVE_EXPR) |
7088 | && ! (TREE_CONSTANT (TREE_OPERAND (t, 2)) | |
2f939d94 | 7089 | || DECL_P (TREE_OPERAND (t, 2)) |
e1f56f62 RK |
7090 | || TREE_CODE (TREE_OPERAND (t, 2)) == SAVE_EXPR)) |
7091 | { | |
7092 | /* See if this can be inverted. If it can't, possibly because | |
7093 | it was a floating-point inequality comparison, don't do | |
7094 | anything. */ | |
7095 | tem = invert_truthvalue (arg0); | |
7096 | ||
7097 | if (TREE_CODE (tem) != TRUTH_NOT_EXPR) | |
7098 | { | |
cd7ece66 RK |
7099 | t = build (code, type, tem, |
7100 | TREE_OPERAND (t, 2), TREE_OPERAND (t, 1)); | |
7101 | arg0 = tem; | |
c479c2ac JL |
7102 | /* arg1 should be the first argument of the new T. */ |
7103 | arg1 = TREE_OPERAND (t, 1); | |
3a96b5eb | 7104 | STRIP_NOPS (arg1); |
e1f56f62 RK |
7105 | } |
7106 | } | |
7107 | ||
c05a9b68 RS |
7108 | /* Convert A ? 1 : 0 to simply A. */ |
7109 | if (integer_onep (TREE_OPERAND (t, 1)) | |
7110 | && integer_zerop (TREE_OPERAND (t, 2)) | |
7111 | /* If we try to convert TREE_OPERAND (t, 0) to our type, the | |
b6cc0a72 | 7112 | call to fold will try to move the conversion inside |
c05a9b68 RS |
7113 | a COND, which will recurse. In that case, the COND_EXPR |
7114 | is probably the best choice, so leave it alone. */ | |
7115 | && type == TREE_TYPE (arg0)) | |
a5e9b124 | 7116 | return pedantic_non_lvalue (arg0); |
6d716ca8 | 7117 | |
c05a9b68 RS |
7118 | /* Look for expressions of the form A & 2 ? 2 : 0. The result of this |
7119 | operation is simply A & 2. */ | |
6d716ca8 RS |
7120 | |
7121 | if (integer_zerop (TREE_OPERAND (t, 2)) | |
7122 | && TREE_CODE (arg0) == NE_EXPR | |
7123 | && integer_zerop (TREE_OPERAND (arg0, 1)) | |
c05a9b68 RS |
7124 | && integer_pow2p (arg1) |
7125 | && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR | |
7126 | && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1), | |
7127 | arg1, 1)) | |
a5e9b124 | 7128 | return pedantic_non_lvalue (convert (type, TREE_OPERAND (arg0, 0))); |
6d716ca8 | 7129 | |
6d716ca8 RS |
7130 | return t; |
7131 | ||
7132 | case COMPOUND_EXPR: | |
b7647895 JW |
7133 | /* When pedantic, a compound expression can be neither an lvalue |
7134 | nor an integer constant expression. */ | |
7135 | if (TREE_SIDE_EFFECTS (arg0) || pedantic) | |
d023bff9 RS |
7136 | return t; |
7137 | /* Don't let (0, 0) be null pointer constant. */ | |
7138 | if (integer_zerop (arg1)) | |
13eb1f7f RK |
7139 | return build1 (NOP_EXPR, type, arg1); |
7140 | return convert (type, arg1); | |
6d716ca8 | 7141 | |
1cc1b11a RS |
7142 | case COMPLEX_EXPR: |
7143 | if (wins) | |
214d5b84 | 7144 | return build_complex (type, arg0, arg1); |
1cc1b11a RS |
7145 | return t; |
7146 | ||
7147 | case REALPART_EXPR: | |
a333b79f | 7148 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) |
1cc1b11a RS |
7149 | return t; |
7150 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
7151 | return omit_one_operand (type, TREE_OPERAND (arg0, 0), | |
7152 | TREE_OPERAND (arg0, 1)); | |
7153 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
7154 | return TREE_REALPART (arg0); | |
7155 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
a3279355 RK |
7156 | return fold (build (TREE_CODE (arg0), type, |
7157 | fold (build1 (REALPART_EXPR, type, | |
7158 | TREE_OPERAND (arg0, 0))), | |
7159 | fold (build1 (REALPART_EXPR, | |
7160 | type, TREE_OPERAND (arg0, 1))))); | |
1cc1b11a RS |
7161 | return t; |
7162 | ||
7163 | case IMAGPART_EXPR: | |
a333b79f | 7164 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) |
1cc1b11a RS |
7165 | return convert (type, integer_zero_node); |
7166 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
7167 | return omit_one_operand (type, TREE_OPERAND (arg0, 1), | |
7168 | TREE_OPERAND (arg0, 0)); | |
7169 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
7170 | return TREE_IMAGPART (arg0); | |
7171 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
a3279355 RK |
7172 | return fold (build (TREE_CODE (arg0), type, |
7173 | fold (build1 (IMAGPART_EXPR, type, | |
7174 | TREE_OPERAND (arg0, 0))), | |
7175 | fold (build1 (IMAGPART_EXPR, type, | |
7176 | TREE_OPERAND (arg0, 1))))); | |
1cc1b11a RS |
7177 | return t; |
7178 | ||
56c98e5b JM |
7179 | /* Pull arithmetic ops out of the CLEANUP_POINT_EXPR where |
7180 | appropriate. */ | |
7181 | case CLEANUP_POINT_EXPR: | |
b7f6588d | 7182 | if (! has_cleanups (arg0)) |
3ffcb234 | 7183 | return TREE_OPERAND (t, 0); |
56c98e5b JM |
7184 | |
7185 | { | |
7186 | enum tree_code code0 = TREE_CODE (arg0); | |
7187 | int kind0 = TREE_CODE_CLASS (code0); | |
7188 | tree arg00 = TREE_OPERAND (arg0, 0); | |
7189 | tree arg01; | |
7190 | ||
0982a4b8 | 7191 | if (kind0 == '1' || code0 == TRUTH_NOT_EXPR) |
b6cc0a72 | 7192 | return fold (build1 (code0, type, |
56c98e5b JM |
7193 | fold (build1 (CLEANUP_POINT_EXPR, |
7194 | TREE_TYPE (arg00), arg00)))); | |
0982a4b8 JM |
7195 | |
7196 | if (kind0 == '<' || kind0 == '2' | |
7197 | || code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR | |
7198 | || code0 == TRUTH_AND_EXPR || code0 == TRUTH_OR_EXPR | |
7199 | || code0 == TRUTH_XOR_EXPR) | |
7200 | { | |
7201 | arg01 = TREE_OPERAND (arg0, 1); | |
7202 | ||
b7f6588d JM |
7203 | if (TREE_CONSTANT (arg00) |
7204 | || ((code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR) | |
7205 | && ! has_cleanups (arg00))) | |
0982a4b8 JM |
7206 | return fold (build (code0, type, arg00, |
7207 | fold (build1 (CLEANUP_POINT_EXPR, | |
7208 | TREE_TYPE (arg01), arg01)))); | |
7209 | ||
b7f6588d | 7210 | if (TREE_CONSTANT (arg01)) |
0982a4b8 JM |
7211 | return fold (build (code0, type, |
7212 | fold (build1 (CLEANUP_POINT_EXPR, | |
7213 | TREE_TYPE (arg00), arg00)), | |
7214 | arg01)); | |
7215 | } | |
56c98e5b JM |
7216 | |
7217 | return t; | |
7218 | } | |
7219 | ||
b0b3afb2 BS |
7220 | case CALL_EXPR: |
7221 | /* Check for a built-in function. */ | |
7222 | if (TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR | |
7223 | && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (expr, 0), 0)) | |
7224 | == FUNCTION_DECL) | |
7225 | && DECL_BUILT_IN (TREE_OPERAND (TREE_OPERAND (expr, 0), 0))) | |
7226 | { | |
7227 | tree tmp = fold_builtin (expr); | |
7228 | if (tmp) | |
7229 | return tmp; | |
7230 | } | |
7231 | return t; | |
7232 | ||
6d716ca8 RS |
7233 | default: |
7234 | return t; | |
7235 | } /* switch (code) */ | |
7236 | } | |
39dfb55a | 7237 | |
c5c76735 JL |
7238 | /* Determine if first argument is a multiple of second argument. Return 0 if |
7239 | it is not, or we cannot easily determined it to be. | |
39dfb55a | 7240 | |
c5c76735 JL |
7241 | An example of the sort of thing we care about (at this point; this routine |
7242 | could surely be made more general, and expanded to do what the *_DIV_EXPR's | |
7243 | fold cases do now) is discovering that | |
39dfb55a JL |
7244 | |
7245 | SAVE_EXPR (I) * SAVE_EXPR (J * 8) | |
7246 | ||
7247 | is a multiple of | |
7248 | ||
7249 | SAVE_EXPR (J * 8) | |
7250 | ||
c5c76735 | 7251 | when we know that the two SAVE_EXPR (J * 8) nodes are the same node. |
39dfb55a JL |
7252 | |
7253 | This code also handles discovering that | |
7254 | ||
7255 | SAVE_EXPR (I) * SAVE_EXPR (J * 8) | |
7256 | ||
c5c76735 | 7257 | is a multiple of 8 so we don't have to worry about dealing with a |
39dfb55a JL |
7258 | possible remainder. |
7259 | ||
c5c76735 JL |
7260 | Note that we *look* inside a SAVE_EXPR only to determine how it was |
7261 | calculated; it is not safe for fold to do much of anything else with the | |
7262 | internals of a SAVE_EXPR, since it cannot know when it will be evaluated | |
7263 | at run time. For example, the latter example above *cannot* be implemented | |
7264 | as SAVE_EXPR (I) * J or any variant thereof, since the value of J at | |
7265 | evaluation time of the original SAVE_EXPR is not necessarily the same at | |
7266 | the time the new expression is evaluated. The only optimization of this | |
39dfb55a JL |
7267 | sort that would be valid is changing |
7268 | ||
7269 | SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8) | |
39dfb55a | 7270 | |
c5c76735 | 7271 | divided by 8 to |
39dfb55a JL |
7272 | |
7273 | SAVE_EXPR (I) * SAVE_EXPR (J) | |
7274 | ||
7275 | (where the same SAVE_EXPR (J) is used in the original and the | |
7276 | transformed version). */ | |
7277 | ||
7278 | static int | |
7279 | multiple_of_p (type, top, bottom) | |
7280 | tree type; | |
7281 | tree top; | |
7282 | tree bottom; | |
7283 | { | |
7284 | if (operand_equal_p (top, bottom, 0)) | |
7285 | return 1; | |
7286 | ||
7287 | if (TREE_CODE (type) != INTEGER_TYPE) | |
7288 | return 0; | |
7289 | ||
7290 | switch (TREE_CODE (top)) | |
7291 | { | |
7292 | case MULT_EXPR: | |
7293 | return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom) | |
7294 | || multiple_of_p (type, TREE_OPERAND (top, 1), bottom)); | |
7295 | ||
7296 | case PLUS_EXPR: | |
7297 | case MINUS_EXPR: | |
7298 | return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom) | |
7299 | && multiple_of_p (type, TREE_OPERAND (top, 1), bottom)); | |
7300 | ||
fba2c0cd JJ |
7301 | case LSHIFT_EXPR: |
7302 | if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST) | |
7303 | { | |
7304 | tree op1, t1; | |
7305 | ||
7306 | op1 = TREE_OPERAND (top, 1); | |
7307 | /* const_binop may not detect overflow correctly, | |
7308 | so check for it explicitly here. */ | |
7309 | if (TYPE_PRECISION (TREE_TYPE (size_one_node)) | |
7310 | > TREE_INT_CST_LOW (op1) | |
7311 | && TREE_INT_CST_HIGH (op1) == 0 | |
7312 | && 0 != (t1 = convert (type, | |
7313 | const_binop (LSHIFT_EXPR, size_one_node, | |
7314 | op1, 0))) | |
7315 | && ! TREE_OVERFLOW (t1)) | |
7316 | return multiple_of_p (type, t1, bottom); | |
7317 | } | |
7318 | return 0; | |
7319 | ||
39dfb55a | 7320 | case NOP_EXPR: |
c5c76735 | 7321 | /* Can't handle conversions from non-integral or wider integral type. */ |
39dfb55a JL |
7322 | if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE) |
7323 | || (TYPE_PRECISION (type) | |
7324 | < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0))))) | |
7325 | return 0; | |
c5c76735 JL |
7326 | |
7327 | /* .. fall through ... */ | |
7328 | ||
39dfb55a JL |
7329 | case SAVE_EXPR: |
7330 | return multiple_of_p (type, TREE_OPERAND (top, 0), bottom); | |
7331 | ||
7332 | case INTEGER_CST: | |
fba2c0cd JJ |
7333 | if (TREE_CODE (bottom) != INTEGER_CST |
7334 | || (TREE_UNSIGNED (type) | |
7335 | && (tree_int_cst_sgn (top) < 0 | |
7336 | || tree_int_cst_sgn (bottom) < 0))) | |
39dfb55a JL |
7337 | return 0; |
7338 | return integer_zerop (const_binop (TRUNC_MOD_EXPR, | |
7339 | top, bottom, 0)); | |
7340 | ||
7341 | default: | |
7342 | return 0; | |
7343 | } | |
7344 | } | |
a36556a8 ZW |
7345 | |
7346 | /* Return true if `t' is known to be non-negative. */ | |
7347 | ||
7348 | int | |
7349 | tree_expr_nonnegative_p (t) | |
7350 | tree t; | |
7351 | { | |
7352 | switch (TREE_CODE (t)) | |
7353 | { | |
7354 | case INTEGER_CST: | |
7355 | return tree_int_cst_sgn (t) >= 0; | |
7356 | case COND_EXPR: | |
7357 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)) | |
7358 | && tree_expr_nonnegative_p (TREE_OPERAND (t, 2)); | |
7359 | case BIND_EXPR: | |
7360 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
7361 | case RTL_EXPR: | |
7362 | return rtl_expr_nonnegative_p (RTL_EXPR_RTL (t)); | |
7363 | ||
7364 | default: | |
9d2dc7da KG |
7365 | if (truth_value_p (TREE_CODE (t))) |
7366 | /* Truth values evaluate to 0 or 1, which is nonnegative. */ | |
7367 | return 1; | |
7368 | else | |
7369 | /* We don't know sign of `t', so be conservative and return false. */ | |
7370 | return 0; | |
a36556a8 ZW |
7371 | } |
7372 | } | |
7373 | ||
7374 | /* Return true if `r' is known to be non-negative. | |
7375 | Only handles constants at the moment. */ | |
7376 | ||
7377 | int | |
7378 | rtl_expr_nonnegative_p (r) | |
7379 | rtx r; | |
7380 | { | |
7381 | switch (GET_CODE (r)) | |
7382 | { | |
7383 | case CONST_INT: | |
7384 | return INTVAL (r) >= 0; | |
7385 | ||
7386 | case CONST_DOUBLE: | |
7387 | if (GET_MODE (r) == VOIDmode) | |
7388 | return CONST_DOUBLE_HIGH (r) >= 0; | |
7389 | return 0; | |
7390 | ||
7391 | case SYMBOL_REF: | |
7392 | case LABEL_REF: | |
7393 | /* These are always nonnegative. */ | |
7394 | return 1; | |
7395 | ||
7396 | default: | |
7397 | return 0; | |
7398 | } | |
7399 | } |