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Commit | Line | Data |
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6d716ca8 | 1 | /* Fold a constant sub-tree into a single node for C-compiler |
06ceef4e | 2 | Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, |
d8086cbb | 3 | 1999, 2000, 2001, 2002 Free Software Foundation, Inc. |
6d716ca8 | 4 | |
1322177d | 5 | This file is part of GCC. |
6d716ca8 | 6 | |
1322177d LB |
7 | GCC is free software; you can redistribute it and/or modify it under |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 2, or (at your option) any later | |
10 | version. | |
6d716ca8 | 11 | |
1322177d LB |
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
6d716ca8 RS |
16 | |
17 | You should have received a copy of the GNU General Public License | |
1322177d LB |
18 | along with GCC; see the file COPYING. If not, write to the Free |
19 | Software Foundation, 59 Temple Place - Suite 330, Boston, MA | |
20 | 02111-1307, USA. */ | |
6d716ca8 | 21 | |
6dc42e49 | 22 | /*@@ This file should be rewritten to use an arbitrary precision |
6d716ca8 RS |
23 | @@ representation for "struct tree_int_cst" and "struct tree_real_cst". |
24 | @@ Perhaps the routines could also be used for bc/dc, and made a lib. | |
25 | @@ The routines that translate from the ap rep should | |
26 | @@ warn if precision et. al. is lost. | |
27 | @@ This would also make life easier when this technology is used | |
28 | @@ for cross-compilers. */ | |
29 | ||
f8dac6eb | 30 | /* The entry points in this file are fold, size_int_wide, size_binop |
0da6f3db | 31 | and force_fit_type. |
6d716ca8 RS |
32 | |
33 | fold takes a tree as argument and returns a simplified tree. | |
34 | ||
35 | size_binop takes a tree code for an arithmetic operation | |
36 | and two operands that are trees, and produces a tree for the | |
37 | result, assuming the type comes from `sizetype'. | |
38 | ||
39 | size_int takes an integer value, and creates a tree constant | |
0da6f3db DE |
40 | with type from `sizetype'. |
41 | ||
42 | force_fit_type takes a constant and prior overflow indicator, and | |
43 | forces the value to fit the type. It returns an overflow indicator. */ | |
44 | ||
e9a25f70 | 45 | #include "config.h" |
2fde567e | 46 | #include "system.h" |
6d716ca8 RS |
47 | #include "flags.h" |
48 | #include "tree.h" | |
11ad4784 | 49 | #include "real.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" |
4c160717 | 55 | #include "hashtab.h" |
43577e6b | 56 | #include "langhooks.h" |
6d716ca8 | 57 | |
711d877c | 58 | static void encode PARAMS ((HOST_WIDE_INT *, |
05bccae2 RK |
59 | unsigned HOST_WIDE_INT, |
60 | HOST_WIDE_INT)); | |
711d877c | 61 | static void decode PARAMS ((HOST_WIDE_INT *, |
05bccae2 | 62 | unsigned HOST_WIDE_INT *, |
711d877c KG |
63 | HOST_WIDE_INT *)); |
64 | static tree negate_expr PARAMS ((tree)); | |
65 | static tree split_tree PARAMS ((tree, enum tree_code, tree *, tree *, | |
cff27795 | 66 | tree *, int)); |
711d877c | 67 | static tree associate_trees PARAMS ((tree, tree, enum tree_code, tree)); |
4c160717 | 68 | static tree int_const_binop PARAMS ((enum tree_code, tree, tree, int)); |
711d877c | 69 | static tree const_binop PARAMS ((enum tree_code, tree, tree, int)); |
4c160717 RK |
70 | static hashval_t size_htab_hash PARAMS ((const void *)); |
71 | static int size_htab_eq PARAMS ((const void *, const void *)); | |
711d877c KG |
72 | static tree fold_convert PARAMS ((tree, tree)); |
73 | static enum tree_code invert_tree_comparison PARAMS ((enum tree_code)); | |
74 | static enum tree_code swap_tree_comparison PARAMS ((enum tree_code)); | |
75 | static int truth_value_p PARAMS ((enum tree_code)); | |
76 | static int operand_equal_for_comparison_p PARAMS ((tree, tree, tree)); | |
77 | static int twoval_comparison_p PARAMS ((tree, tree *, tree *, int *)); | |
78 | static tree eval_subst PARAMS ((tree, tree, tree, tree, tree)); | |
79 | static tree omit_one_operand PARAMS ((tree, tree, tree)); | |
80 | static tree pedantic_omit_one_operand PARAMS ((tree, tree, tree)); | |
81 | static tree distribute_bit_expr PARAMS ((enum tree_code, tree, tree, tree)); | |
82 | static tree make_bit_field_ref PARAMS ((tree, tree, int, int, int)); | |
83 | static tree optimize_bit_field_compare PARAMS ((enum tree_code, tree, | |
84 | tree, tree)); | |
770ae6cc RK |
85 | static tree decode_field_reference PARAMS ((tree, HOST_WIDE_INT *, |
86 | HOST_WIDE_INT *, | |
711d877c KG |
87 | enum machine_mode *, int *, |
88 | int *, tree *, tree *)); | |
89 | static int all_ones_mask_p PARAMS ((tree, int)); | |
1f77b5da | 90 | static tree sign_bit_p PARAMS ((tree, tree)); |
711d877c KG |
91 | static int simple_operand_p PARAMS ((tree)); |
92 | static tree range_binop PARAMS ((enum tree_code, tree, tree, int, | |
93 | tree, int)); | |
94 | static tree make_range PARAMS ((tree, int *, tree *, tree *)); | |
95 | static tree build_range_check PARAMS ((tree, tree, int, tree, tree)); | |
96 | static int merge_ranges PARAMS ((int *, tree *, tree *, int, tree, tree, | |
ebde8a27 | 97 | int, tree, tree)); |
711d877c KG |
98 | static tree fold_range_test PARAMS ((tree)); |
99 | static tree unextend PARAMS ((tree, int, int, tree)); | |
100 | static tree fold_truthop PARAMS ((enum tree_code, tree, tree, tree)); | |
101 | static tree optimize_minmax_comparison PARAMS ((tree)); | |
102 | static tree extract_muldiv PARAMS ((tree, tree, enum tree_code, tree)); | |
103 | static tree strip_compound_expr PARAMS ((tree, tree)); | |
104 | static int multiple_of_p PARAMS ((tree, tree, tree)); | |
105 | static tree constant_boolean_node PARAMS ((int, tree)); | |
106 | static int count_cond PARAMS ((tree, int)); | |
dd3f0101 | 107 | static tree fold_binary_op_with_conditional_arg |
68626d4f | 108 | PARAMS ((enum tree_code, tree, tree, tree, int)); |
71925bc0 | 109 | static bool fold_real_zero_addition_p PARAMS ((tree, tree, int)); |
dd3f0101 | 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]; | |
b3694847 SS |
322 | unsigned HOST_WIDE_INT carry; |
323 | 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 | { | |
11b161d0 JW |
381 | unsigned HOST_WIDE_INT signmask; |
382 | ||
6d716ca8 RS |
383 | if (count < 0) |
384 | { | |
b6cc0a72 | 385 | rshift_double (l1, h1, -count, prec, lv, hv, arith); |
e0f776fb | 386 | return; |
6d716ca8 | 387 | } |
b6cc0a72 | 388 | |
3d1877b1 RK |
389 | #ifdef SHIFT_COUNT_TRUNCATED |
390 | if (SHIFT_COUNT_TRUNCATED) | |
391 | count %= prec; | |
392 | #endif | |
6d716ca8 | 393 | |
cb0a34c4 JW |
394 | if (count >= 2 * HOST_BITS_PER_WIDE_INT) |
395 | { | |
396 | /* Shifting by the host word size is undefined according to the | |
397 | ANSI standard, so we must handle this as a special case. */ | |
398 | *hv = 0; | |
399 | *lv = 0; | |
400 | } | |
401 | else if (count >= HOST_BITS_PER_WIDE_INT) | |
6d716ca8 | 402 | { |
05bccae2 | 403 | *hv = l1 << (count - HOST_BITS_PER_WIDE_INT); |
37bdb7e3 TG |
404 | *lv = 0; |
405 | } | |
406 | else | |
407 | { | |
408 | *hv = (((unsigned HOST_WIDE_INT) h1 << count) | |
05bccae2 RK |
409 | | (l1 >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1)); |
410 | *lv = l1 << count; | |
6d716ca8 | 411 | } |
11b161d0 JW |
412 | |
413 | /* Sign extend all bits that are beyond the precision. */ | |
414 | ||
415 | signmask = -((prec > HOST_BITS_PER_WIDE_INT | |
0316d49b | 416 | ? ((unsigned HOST_WIDE_INT) *hv |
dd3f0101 | 417 | >> (prec - HOST_BITS_PER_WIDE_INT - 1)) |
11b161d0 JW |
418 | : (*lv >> (prec - 1))) & 1); |
419 | ||
420 | if (prec >= 2 * HOST_BITS_PER_WIDE_INT) | |
421 | ; | |
422 | else if (prec >= HOST_BITS_PER_WIDE_INT) | |
423 | { | |
424 | *hv &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT)); | |
425 | *hv |= signmask << (prec - HOST_BITS_PER_WIDE_INT); | |
426 | } | |
427 | else | |
428 | { | |
429 | *hv = signmask; | |
430 | *lv &= ~((unsigned HOST_WIDE_INT) (-1) << prec); | |
431 | *lv |= signmask << prec; | |
432 | } | |
6d716ca8 RS |
433 | } |
434 | ||
906c4e36 | 435 | /* Shift the doubleword integer in L1, H1 right by COUNT places |
6d716ca8 RS |
436 | keeping only PREC bits of result. COUNT must be positive. |
437 | ARITH nonzero specifies arithmetic shifting; otherwise use logical shift. | |
906c4e36 | 438 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
439 | |
440 | void | |
441 | rshift_double (l1, h1, count, prec, lv, hv, arith) | |
05bccae2 RK |
442 | unsigned HOST_WIDE_INT l1; |
443 | HOST_WIDE_INT h1, count; | |
11b161d0 | 444 | unsigned int prec; |
05bccae2 RK |
445 | unsigned HOST_WIDE_INT *lv; |
446 | HOST_WIDE_INT *hv; | |
6d716ca8 RS |
447 | int arith; |
448 | { | |
37bdb7e3 | 449 | unsigned HOST_WIDE_INT signmask; |
05bccae2 | 450 | |
37bdb7e3 TG |
451 | signmask = (arith |
452 | ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1)) | |
453 | : 0); | |
6d716ca8 | 454 | |
3d1877b1 RK |
455 | #ifdef SHIFT_COUNT_TRUNCATED |
456 | if (SHIFT_COUNT_TRUNCATED) | |
457 | count %= prec; | |
458 | #endif | |
6d716ca8 | 459 | |
cb0a34c4 JW |
460 | if (count >= 2 * HOST_BITS_PER_WIDE_INT) |
461 | { | |
462 | /* Shifting by the host word size is undefined according to the | |
463 | ANSI standard, so we must handle this as a special case. */ | |
11b161d0 JW |
464 | *hv = 0; |
465 | *lv = 0; | |
cb0a34c4 JW |
466 | } |
467 | else if (count >= HOST_BITS_PER_WIDE_INT) | |
6d716ca8 | 468 | { |
11b161d0 JW |
469 | *hv = 0; |
470 | *lv = (unsigned HOST_WIDE_INT) h1 >> (count - HOST_BITS_PER_WIDE_INT); | |
37bdb7e3 TG |
471 | } |
472 | else | |
473 | { | |
11b161d0 | 474 | *hv = (unsigned HOST_WIDE_INT) h1 >> count; |
05bccae2 | 475 | *lv = ((l1 >> count) |
2fde567e | 476 | | ((unsigned HOST_WIDE_INT) h1 << (HOST_BITS_PER_WIDE_INT - count - 1) << 1)); |
11b161d0 JW |
477 | } |
478 | ||
479 | /* Zero / sign extend all bits that are beyond the precision. */ | |
480 | ||
481 | if (count >= (HOST_WIDE_INT)prec) | |
482 | { | |
483 | *hv = signmask; | |
484 | *lv = signmask; | |
485 | } | |
486 | else if ((prec - count) >= 2 * HOST_BITS_PER_WIDE_INT) | |
487 | ; | |
488 | else if ((prec - count) >= HOST_BITS_PER_WIDE_INT) | |
489 | { | |
490 | *hv &= ~((HOST_WIDE_INT) (-1) << (prec - count - HOST_BITS_PER_WIDE_INT)); | |
491 | *hv |= signmask << (prec - count - HOST_BITS_PER_WIDE_INT); | |
492 | } | |
493 | else | |
494 | { | |
495 | *hv = signmask; | |
496 | *lv &= ~((unsigned HOST_WIDE_INT) (-1) << (prec - count)); | |
497 | *lv |= signmask << (prec - count); | |
6d716ca8 | 498 | } |
6d716ca8 RS |
499 | } |
500 | \f | |
37bdb7e3 | 501 | /* Rotate the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 RS |
502 | keeping only PREC bits of result. |
503 | Rotate right if COUNT is negative. | |
906c4e36 | 504 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
505 | |
506 | void | |
507 | lrotate_double (l1, h1, count, prec, lv, hv) | |
05bccae2 RK |
508 | unsigned HOST_WIDE_INT l1; |
509 | HOST_WIDE_INT h1, count; | |
510 | unsigned int prec; | |
511 | unsigned HOST_WIDE_INT *lv; | |
512 | HOST_WIDE_INT *hv; | |
6d716ca8 | 513 | { |
05bccae2 RK |
514 | unsigned HOST_WIDE_INT s1l, s2l; |
515 | HOST_WIDE_INT s1h, s2h; | |
6d716ca8 | 516 | |
4d39710e | 517 | count %= prec; |
6d716ca8 | 518 | if (count < 0) |
4d39710e | 519 | count += prec; |
6d716ca8 | 520 | |
4d39710e RK |
521 | lshift_double (l1, h1, count, prec, &s1l, &s1h, 0); |
522 | rshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0); | |
523 | *lv = s1l | s2l; | |
524 | *hv = s1h | s2h; | |
6d716ca8 RS |
525 | } |
526 | ||
906c4e36 | 527 | /* Rotate the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 | 528 | keeping only PREC bits of result. COUNT must be positive. |
906c4e36 | 529 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
530 | |
531 | void | |
532 | rrotate_double (l1, h1, count, prec, lv, hv) | |
05bccae2 RK |
533 | unsigned HOST_WIDE_INT l1; |
534 | HOST_WIDE_INT h1, count; | |
535 | unsigned int prec; | |
536 | unsigned HOST_WIDE_INT *lv; | |
537 | HOST_WIDE_INT *hv; | |
6d716ca8 | 538 | { |
05bccae2 RK |
539 | unsigned HOST_WIDE_INT s1l, s2l; |
540 | HOST_WIDE_INT s1h, s2h; | |
6d716ca8 | 541 | |
4d39710e RK |
542 | count %= prec; |
543 | if (count < 0) | |
544 | count += prec; | |
6d716ca8 | 545 | |
4d39710e RK |
546 | rshift_double (l1, h1, count, prec, &s1l, &s1h, 0); |
547 | lshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0); | |
548 | *lv = s1l | s2l; | |
549 | *hv = s1h | s2h; | |
6d716ca8 RS |
550 | } |
551 | \f | |
906c4e36 | 552 | /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN |
6d716ca8 RS |
553 | for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM). |
554 | CODE is a tree code for a kind of division, one of | |
555 | TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR | |
556 | or EXACT_DIV_EXPR | |
4fe9b91c | 557 | It controls how the quotient is rounded to an integer. |
fe3e8e40 | 558 | Return nonzero if the operation overflows. |
6d716ca8 RS |
559 | UNS nonzero says do unsigned division. */ |
560 | ||
dbb5b3ce | 561 | int |
6d716ca8 RS |
562 | div_and_round_double (code, uns, |
563 | lnum_orig, hnum_orig, lden_orig, hden_orig, | |
564 | lquo, hquo, lrem, hrem) | |
565 | enum tree_code code; | |
566 | int uns; | |
05bccae2 RK |
567 | unsigned HOST_WIDE_INT lnum_orig; /* num == numerator == dividend */ |
568 | HOST_WIDE_INT hnum_orig; | |
569 | unsigned HOST_WIDE_INT lden_orig; /* den == denominator == divisor */ | |
570 | HOST_WIDE_INT hden_orig; | |
571 | unsigned HOST_WIDE_INT *lquo, *lrem; | |
572 | HOST_WIDE_INT *hquo, *hrem; | |
6d716ca8 RS |
573 | { |
574 | int quo_neg = 0; | |
37bdb7e3 TG |
575 | HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */ |
576 | HOST_WIDE_INT den[4], quo[4]; | |
b3694847 | 577 | int i, j; |
37bdb7e3 | 578 | unsigned HOST_WIDE_INT work; |
05bccae2 RK |
579 | unsigned HOST_WIDE_INT carry = 0; |
580 | unsigned HOST_WIDE_INT lnum = lnum_orig; | |
b8eb43a2 | 581 | HOST_WIDE_INT hnum = hnum_orig; |
05bccae2 | 582 | unsigned HOST_WIDE_INT lden = lden_orig; |
b8eb43a2 | 583 | HOST_WIDE_INT hden = hden_orig; |
fe3e8e40 | 584 | int overflow = 0; |
6d716ca8 | 585 | |
05bccae2 | 586 | if (hden == 0 && lden == 0) |
956d6950 | 587 | overflow = 1, lden = 1; |
6d716ca8 RS |
588 | |
589 | /* calculate quotient sign and convert operands to unsigned. */ | |
b6cc0a72 | 590 | if (!uns) |
6d716ca8 | 591 | { |
fe3e8e40 | 592 | if (hnum < 0) |
6d716ca8 RS |
593 | { |
594 | quo_neg = ~ quo_neg; | |
fe3e8e40 | 595 | /* (minimum integer) / (-1) is the only overflow case. */ |
05bccae2 RK |
596 | if (neg_double (lnum, hnum, &lnum, &hnum) |
597 | && ((HOST_WIDE_INT) lden & hden) == -1) | |
fe3e8e40 | 598 | overflow = 1; |
6d716ca8 | 599 | } |
b6cc0a72 | 600 | if (hden < 0) |
6d716ca8 RS |
601 | { |
602 | quo_neg = ~ quo_neg; | |
fe3e8e40 | 603 | neg_double (lden, hden, &lden, &hden); |
6d716ca8 RS |
604 | } |
605 | } | |
606 | ||
607 | if (hnum == 0 && hden == 0) | |
608 | { /* single precision */ | |
609 | *hquo = *hrem = 0; | |
88ee2651 | 610 | /* This unsigned division rounds toward zero. */ |
05bccae2 | 611 | *lquo = lnum / lden; |
6d716ca8 RS |
612 | goto finish_up; |
613 | } | |
614 | ||
615 | if (hnum == 0) | |
616 | { /* trivial case: dividend < divisor */ | |
617 | /* hden != 0 already checked. */ | |
618 | *hquo = *lquo = 0; | |
619 | *hrem = hnum; | |
620 | *lrem = lnum; | |
621 | goto finish_up; | |
622 | } | |
623 | ||
961192e1 | 624 | memset ((char *) quo, 0, sizeof quo); |
6d716ca8 | 625 | |
961192e1 JM |
626 | memset ((char *) num, 0, sizeof num); /* to zero 9th element */ |
627 | memset ((char *) den, 0, sizeof den); | |
6d716ca8 | 628 | |
b6cc0a72 | 629 | encode (num, lnum, hnum); |
6d716ca8 RS |
630 | encode (den, lden, hden); |
631 | ||
37bdb7e3 | 632 | /* Special code for when the divisor < BASE. */ |
05bccae2 | 633 | if (hden == 0 && lden < (unsigned HOST_WIDE_INT) BASE) |
37bdb7e3 | 634 | { |
6d716ca8 | 635 | /* hnum != 0 already checked. */ |
37bdb7e3 | 636 | for (i = 4 - 1; i >= 0; i--) |
6d716ca8 | 637 | { |
37bdb7e3 | 638 | work = num[i] + carry * BASE; |
05bccae2 RK |
639 | quo[i] = work / lden; |
640 | carry = work % lden; | |
6d716ca8 RS |
641 | } |
642 | } | |
37bdb7e3 TG |
643 | else |
644 | { | |
645 | /* Full double precision division, | |
646 | with thanks to Don Knuth's "Seminumerical Algorithms". */ | |
05bccae2 RK |
647 | int num_hi_sig, den_hi_sig; |
648 | unsigned HOST_WIDE_INT quo_est, scale; | |
6d716ca8 | 649 | |
05bccae2 | 650 | /* Find the highest non-zero divisor digit. */ |
b6cc0a72 KH |
651 | for (i = 4 - 1;; i--) |
652 | if (den[i] != 0) | |
653 | { | |
654 | den_hi_sig = i; | |
655 | break; | |
656 | } | |
37bdb7e3 | 657 | |
05bccae2 RK |
658 | /* Insure that the first digit of the divisor is at least BASE/2. |
659 | This is required by the quotient digit estimation algorithm. */ | |
6d716ca8 | 660 | |
05bccae2 RK |
661 | scale = BASE / (den[den_hi_sig] + 1); |
662 | if (scale > 1) | |
663 | { /* scale divisor and dividend */ | |
664 | carry = 0; | |
665 | for (i = 0; i <= 4 - 1; i++) | |
666 | { | |
667 | work = (num[i] * scale) + carry; | |
668 | num[i] = LOWPART (work); | |
669 | carry = HIGHPART (work); | |
670 | } | |
6d716ca8 | 671 | |
05bccae2 RK |
672 | num[4] = carry; |
673 | carry = 0; | |
674 | for (i = 0; i <= 4 - 1; i++) | |
675 | { | |
676 | work = (den[i] * scale) + carry; | |
677 | den[i] = LOWPART (work); | |
678 | carry = HIGHPART (work); | |
679 | if (den[i] != 0) den_hi_sig = i; | |
680 | } | |
681 | } | |
6d716ca8 | 682 | |
05bccae2 | 683 | num_hi_sig = 4; |
6d716ca8 | 684 | |
05bccae2 RK |
685 | /* Main loop */ |
686 | for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--) | |
6d716ca8 | 687 | { |
05bccae2 RK |
688 | /* Guess the next quotient digit, quo_est, by dividing the first |
689 | two remaining dividend digits by the high order quotient digit. | |
690 | quo_est is never low and is at most 2 high. */ | |
691 | unsigned HOST_WIDE_INT tmp; | |
692 | ||
693 | num_hi_sig = i + den_hi_sig + 1; | |
694 | work = num[num_hi_sig] * BASE + num[num_hi_sig - 1]; | |
695 | if (num[num_hi_sig] != den[den_hi_sig]) | |
696 | quo_est = work / den[den_hi_sig]; | |
697 | else | |
698 | quo_est = BASE - 1; | |
6d716ca8 | 699 | |
6d2f8887 | 700 | /* Refine quo_est so it's usually correct, and at most one high. */ |
05bccae2 RK |
701 | tmp = work - quo_est * den[den_hi_sig]; |
702 | if (tmp < BASE | |
703 | && (den[den_hi_sig - 1] * quo_est | |
704 | > (tmp * BASE + num[num_hi_sig - 2]))) | |
705 | quo_est--; | |
6d716ca8 | 706 | |
05bccae2 RK |
707 | /* Try QUO_EST as the quotient digit, by multiplying the |
708 | divisor by QUO_EST and subtracting from the remaining dividend. | |
709 | Keep in mind that QUO_EST is the I - 1st digit. */ | |
710 | ||
711 | carry = 0; | |
6d716ca8 RS |
712 | for (j = 0; j <= den_hi_sig; j++) |
713 | { | |
05bccae2 | 714 | work = quo_est * den[j] + carry; |
37bdb7e3 | 715 | carry = HIGHPART (work); |
05bccae2 | 716 | work = num[i + j] - LOWPART (work); |
37bdb7e3 | 717 | num[i + j] = LOWPART (work); |
05bccae2 | 718 | carry += HIGHPART (work) != 0; |
6d716ca8 | 719 | } |
6d716ca8 | 720 | |
05bccae2 RK |
721 | /* If quo_est was high by one, then num[i] went negative and |
722 | we need to correct things. */ | |
0316d49b | 723 | if (num[num_hi_sig] < (HOST_WIDE_INT) carry) |
05bccae2 RK |
724 | { |
725 | quo_est--; | |
726 | carry = 0; /* add divisor back in */ | |
727 | for (j = 0; j <= den_hi_sig; j++) | |
728 | { | |
729 | work = num[i + j] + den[j] + carry; | |
730 | carry = HIGHPART (work); | |
731 | num[i + j] = LOWPART (work); | |
732 | } | |
733 | ||
734 | num [num_hi_sig] += carry; | |
735 | } | |
736 | ||
737 | /* Store the quotient digit. */ | |
738 | quo[i] = quo_est; | |
739 | } | |
6d716ca8 | 740 | } |
6d716ca8 RS |
741 | |
742 | decode (quo, lquo, hquo); | |
743 | ||
744 | finish_up: | |
745 | /* if result is negative, make it so. */ | |
746 | if (quo_neg) | |
747 | neg_double (*lquo, *hquo, lquo, hquo); | |
748 | ||
749 | /* compute trial remainder: rem = num - (quo * den) */ | |
750 | mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem); | |
751 | neg_double (*lrem, *hrem, lrem, hrem); | |
752 | add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem); | |
753 | ||
754 | switch (code) | |
755 | { | |
756 | case TRUNC_DIV_EXPR: | |
757 | case TRUNC_MOD_EXPR: /* round toward zero */ | |
758 | case EXACT_DIV_EXPR: /* for this one, it shouldn't matter */ | |
fe3e8e40 | 759 | return overflow; |
6d716ca8 RS |
760 | |
761 | case FLOOR_DIV_EXPR: | |
762 | case FLOOR_MOD_EXPR: /* round toward negative infinity */ | |
763 | if (quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio < 0 && rem != 0 */ | |
764 | { | |
765 | /* quo = quo - 1; */ | |
906c4e36 RK |
766 | add_double (*lquo, *hquo, (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, |
767 | lquo, hquo); | |
6d716ca8 | 768 | } |
05bccae2 RK |
769 | else |
770 | return overflow; | |
6d716ca8 RS |
771 | break; |
772 | ||
773 | case CEIL_DIV_EXPR: | |
774 | case CEIL_MOD_EXPR: /* round toward positive infinity */ | |
775 | if (!quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio > 0 && rem != 0 */ | |
776 | { | |
906c4e36 RK |
777 | add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0, |
778 | lquo, hquo); | |
6d716ca8 | 779 | } |
05bccae2 RK |
780 | else |
781 | return overflow; | |
6d716ca8 | 782 | break; |
b6cc0a72 | 783 | |
6d716ca8 RS |
784 | case ROUND_DIV_EXPR: |
785 | case ROUND_MOD_EXPR: /* round to closest integer */ | |
786 | { | |
05bccae2 RK |
787 | unsigned HOST_WIDE_INT labs_rem = *lrem; |
788 | HOST_WIDE_INT habs_rem = *hrem; | |
789 | unsigned HOST_WIDE_INT labs_den = lden, ltwice; | |
790 | HOST_WIDE_INT habs_den = hden, htwice; | |
791 | ||
792 | /* Get absolute values */ | |
793 | if (*hrem < 0) | |
794 | neg_double (*lrem, *hrem, &labs_rem, &habs_rem); | |
795 | if (hden < 0) | |
796 | neg_double (lden, hden, &labs_den, &habs_den); | |
797 | ||
798 | /* If (2 * abs (lrem) >= abs (lden)) */ | |
906c4e36 RK |
799 | mul_double ((HOST_WIDE_INT) 2, (HOST_WIDE_INT) 0, |
800 | labs_rem, habs_rem, <wice, &htwice); | |
05bccae2 | 801 | |
906c4e36 RK |
802 | if (((unsigned HOST_WIDE_INT) habs_den |
803 | < (unsigned HOST_WIDE_INT) htwice) | |
804 | || (((unsigned HOST_WIDE_INT) habs_den | |
805 | == (unsigned HOST_WIDE_INT) htwice) | |
05bccae2 | 806 | && (labs_den < ltwice))) |
6d716ca8 RS |
807 | { |
808 | if (*hquo < 0) | |
809 | /* quo = quo - 1; */ | |
906c4e36 RK |
810 | add_double (*lquo, *hquo, |
811 | (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, lquo, hquo); | |
6d716ca8 RS |
812 | else |
813 | /* quo = quo + 1; */ | |
906c4e36 RK |
814 | add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0, |
815 | lquo, hquo); | |
6d716ca8 | 816 | } |
05bccae2 RK |
817 | else |
818 | return overflow; | |
6d716ca8 RS |
819 | } |
820 | break; | |
821 | ||
822 | default: | |
823 | abort (); | |
824 | } | |
825 | ||
826 | /* compute true remainder: rem = num - (quo * den) */ | |
827 | mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem); | |
828 | neg_double (*lrem, *hrem, lrem, hrem); | |
829 | add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem); | |
fe3e8e40 | 830 | return overflow; |
6d716ca8 RS |
831 | } |
832 | \f | |
1baa375f RK |
833 | /* Given T, an expression, return the negation of T. Allow for T to be |
834 | null, in which case return null. */ | |
6d716ca8 | 835 | |
1baa375f RK |
836 | static tree |
837 | negate_expr (t) | |
838 | tree t; | |
839 | { | |
840 | tree type; | |
841 | tree tem; | |
842 | ||
843 | if (t == 0) | |
844 | return 0; | |
845 | ||
846 | type = TREE_TYPE (t); | |
847 | STRIP_SIGN_NOPS (t); | |
848 | ||
849 | switch (TREE_CODE (t)) | |
850 | { | |
851 | case INTEGER_CST: | |
852 | case REAL_CST: | |
853 | if (! TREE_UNSIGNED (type) | |
854 | && 0 != (tem = fold (build1 (NEGATE_EXPR, type, t))) | |
855 | && ! TREE_OVERFLOW (tem)) | |
856 | return tem; | |
857 | break; | |
858 | ||
859 | case NEGATE_EXPR: | |
860 | return convert (type, TREE_OPERAND (t, 0)); | |
861 | ||
862 | case MINUS_EXPR: | |
863 | /* - (A - B) -> B - A */ | |
de6c5979 | 864 | if (! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations) |
1baa375f RK |
865 | return convert (type, |
866 | fold (build (MINUS_EXPR, TREE_TYPE (t), | |
867 | TREE_OPERAND (t, 1), | |
868 | TREE_OPERAND (t, 0)))); | |
869 | break; | |
870 | ||
871 | default: | |
872 | break; | |
873 | } | |
874 | ||
a094954e | 875 | return convert (type, fold (build1 (NEGATE_EXPR, TREE_TYPE (t), t))); |
1baa375f RK |
876 | } |
877 | \f | |
878 | /* Split a tree IN into a constant, literal and variable parts that could be | |
879 | combined with CODE to make IN. "constant" means an expression with | |
880 | TREE_CONSTANT but that isn't an actual constant. CODE must be a | |
881 | commutative arithmetic operation. Store the constant part into *CONP, | |
cff27795 | 882 | the literal in *LITP and return the variable part. If a part isn't |
1baa375f RK |
883 | present, set it to null. If the tree does not decompose in this way, |
884 | return the entire tree as the variable part and the other parts as null. | |
885 | ||
886 | If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that | |
cff27795 EB |
887 | case, we negate an operand that was subtracted. Except if it is a |
888 | literal for which we use *MINUS_LITP instead. | |
889 | ||
890 | If NEGATE_P is true, we are negating all of IN, again except a literal | |
891 | for which we use *MINUS_LITP instead. | |
1baa375f RK |
892 | |
893 | If IN is itself a literal or constant, return it as appropriate. | |
894 | ||
895 | Note that we do not guarantee that any of the three values will be the | |
896 | same type as IN, but they will have the same signedness and mode. */ | |
897 | ||
898 | static tree | |
cff27795 | 899 | split_tree (in, code, conp, litp, minus_litp, negate_p) |
6d716ca8 RS |
900 | tree in; |
901 | enum tree_code code; | |
cff27795 | 902 | tree *conp, *litp, *minus_litp; |
1baa375f | 903 | int negate_p; |
6d716ca8 | 904 | { |
1baa375f RK |
905 | tree var = 0; |
906 | ||
6d716ca8 | 907 | *conp = 0; |
1baa375f | 908 | *litp = 0; |
cff27795 | 909 | *minus_litp = 0; |
1baa375f | 910 | |
30f7a378 | 911 | /* Strip any conversions that don't change the machine mode or signedness. */ |
1baa375f RK |
912 | STRIP_SIGN_NOPS (in); |
913 | ||
914 | if (TREE_CODE (in) == INTEGER_CST || TREE_CODE (in) == REAL_CST) | |
915 | *litp = in; | |
1baa375f RK |
916 | else if (TREE_CODE (in) == code |
917 | || (! FLOAT_TYPE_P (TREE_TYPE (in)) | |
918 | /* We can associate addition and subtraction together (even | |
919 | though the C standard doesn't say so) for integers because | |
920 | the value is not affected. For reals, the value might be | |
921 | affected, so we can't. */ | |
922 | && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR) | |
923 | || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR)))) | |
924 | { | |
925 | tree op0 = TREE_OPERAND (in, 0); | |
926 | tree op1 = TREE_OPERAND (in, 1); | |
927 | int neg1_p = TREE_CODE (in) == MINUS_EXPR; | |
928 | int neg_litp_p = 0, neg_conp_p = 0, neg_var_p = 0; | |
929 | ||
930 | /* First see if either of the operands is a literal, then a constant. */ | |
931 | if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST) | |
932 | *litp = op0, op0 = 0; | |
933 | else if (TREE_CODE (op1) == INTEGER_CST || TREE_CODE (op1) == REAL_CST) | |
934 | *litp = op1, neg_litp_p = neg1_p, op1 = 0; | |
935 | ||
936 | if (op0 != 0 && TREE_CONSTANT (op0)) | |
937 | *conp = op0, op0 = 0; | |
938 | else if (op1 != 0 && TREE_CONSTANT (op1)) | |
939 | *conp = op1, neg_conp_p = neg1_p, op1 = 0; | |
940 | ||
941 | /* If we haven't dealt with either operand, this is not a case we can | |
30f7a378 | 942 | decompose. Otherwise, VAR is either of the ones remaining, if any. */ |
1baa375f RK |
943 | if (op0 != 0 && op1 != 0) |
944 | var = in; | |
945 | else if (op0 != 0) | |
946 | var = op0; | |
947 | else | |
948 | var = op1, neg_var_p = neg1_p; | |
6d716ca8 | 949 | |
1baa375f | 950 | /* Now do any needed negations. */ |
cff27795 EB |
951 | if (neg_litp_p) |
952 | *minus_litp = *litp, *litp = 0; | |
953 | if (neg_conp_p) | |
954 | *conp = negate_expr (*conp); | |
955 | if (neg_var_p) | |
956 | var = negate_expr (var); | |
1baa375f | 957 | } |
1796dff4 RH |
958 | else if (TREE_CONSTANT (in)) |
959 | *conp = in; | |
1baa375f RK |
960 | else |
961 | var = in; | |
962 | ||
963 | if (negate_p) | |
6d716ca8 | 964 | { |
cff27795 EB |
965 | if (*litp) |
966 | *minus_litp = *litp, *litp = 0; | |
967 | else if (*minus_litp) | |
968 | *litp = *minus_litp, *minus_litp = 0; | |
1baa375f | 969 | *conp = negate_expr (*conp); |
cff27795 | 970 | var = negate_expr (var); |
6d716ca8 | 971 | } |
1baa375f RK |
972 | |
973 | return var; | |
974 | } | |
975 | ||
976 | /* Re-associate trees split by the above function. T1 and T2 are either | |
977 | expressions to associate or null. Return the new expression, if any. If | |
cff27795 | 978 | we build an operation, do it in TYPE and with CODE. */ |
1baa375f RK |
979 | |
980 | static tree | |
981 | associate_trees (t1, t2, code, type) | |
982 | tree t1, t2; | |
983 | enum tree_code code; | |
984 | tree type; | |
985 | { | |
1baa375f RK |
986 | if (t1 == 0) |
987 | return t2; | |
988 | else if (t2 == 0) | |
989 | return t1; | |
990 | ||
1baa375f RK |
991 | /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't |
992 | try to fold this since we will have infinite recursion. But do | |
993 | deal with any NEGATE_EXPRs. */ | |
994 | if (TREE_CODE (t1) == code || TREE_CODE (t2) == code | |
995 | || TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR) | |
996 | { | |
997 | if (TREE_CODE (t1) == NEGATE_EXPR) | |
998 | return build (MINUS_EXPR, type, convert (type, t2), | |
999 | convert (type, TREE_OPERAND (t1, 0))); | |
1000 | else if (TREE_CODE (t2) == NEGATE_EXPR) | |
1001 | return build (MINUS_EXPR, type, convert (type, t1), | |
1002 | convert (type, TREE_OPERAND (t2, 0))); | |
1003 | else | |
1004 | return build (code, type, convert (type, t1), convert (type, t2)); | |
1005 | } | |
1006 | ||
1007 | return fold (build (code, type, convert (type, t1), convert (type, t2))); | |
6d716ca8 RS |
1008 | } |
1009 | \f | |
e9a25f70 | 1010 | /* Combine two integer constants ARG1 and ARG2 under operation CODE |
6d716ca8 | 1011 | to produce a new constant. |
91d33e36 | 1012 | |
4c160717 | 1013 | If NOTRUNC is nonzero, do not truncate the result to fit the data type. */ |
6d716ca8 | 1014 | |
6d716ca8 | 1015 | static tree |
4c160717 | 1016 | int_const_binop (code, arg1, arg2, notrunc) |
6d716ca8 | 1017 | enum tree_code code; |
b3694847 | 1018 | tree arg1, arg2; |
4c160717 | 1019 | int notrunc; |
6d716ca8 | 1020 | { |
05bccae2 RK |
1021 | unsigned HOST_WIDE_INT int1l, int2l; |
1022 | HOST_WIDE_INT int1h, int2h; | |
1023 | unsigned HOST_WIDE_INT low; | |
1024 | HOST_WIDE_INT hi; | |
1025 | unsigned HOST_WIDE_INT garbagel; | |
1026 | HOST_WIDE_INT garbageh; | |
b3694847 | 1027 | tree t; |
4c160717 RK |
1028 | tree type = TREE_TYPE (arg1); |
1029 | int uns = TREE_UNSIGNED (type); | |
1030 | int is_sizetype | |
1031 | = (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type)); | |
e9a25f70 JL |
1032 | int overflow = 0; |
1033 | int no_overflow = 0; | |
3dedc65a | 1034 | |
e9a25f70 JL |
1035 | int1l = TREE_INT_CST_LOW (arg1); |
1036 | int1h = TREE_INT_CST_HIGH (arg1); | |
1037 | int2l = TREE_INT_CST_LOW (arg2); | |
1038 | int2h = TREE_INT_CST_HIGH (arg2); | |
1039 | ||
1040 | switch (code) | |
6d716ca8 | 1041 | { |
e9a25f70 JL |
1042 | case BIT_IOR_EXPR: |
1043 | low = int1l | int2l, hi = int1h | int2h; | |
1044 | break; | |
6d716ca8 | 1045 | |
e9a25f70 JL |
1046 | case BIT_XOR_EXPR: |
1047 | low = int1l ^ int2l, hi = int1h ^ int2h; | |
1048 | break; | |
6d716ca8 | 1049 | |
e9a25f70 JL |
1050 | case BIT_AND_EXPR: |
1051 | low = int1l & int2l, hi = int1h & int2h; | |
1052 | break; | |
6d716ca8 | 1053 | |
e9a25f70 JL |
1054 | case BIT_ANDTC_EXPR: |
1055 | low = int1l & ~int2l, hi = int1h & ~int2h; | |
1056 | break; | |
6d716ca8 | 1057 | |
e9a25f70 | 1058 | case RSHIFT_EXPR: |
b6cc0a72 | 1059 | int2l = -int2l; |
e9a25f70 JL |
1060 | case LSHIFT_EXPR: |
1061 | /* It's unclear from the C standard whether shifts can overflow. | |
1062 | The following code ignores overflow; perhaps a C standard | |
1063 | interpretation ruling is needed. */ | |
4c160717 | 1064 | lshift_double (int1l, int1h, int2l, TYPE_PRECISION (type), |
770ae6cc | 1065 | &low, &hi, !uns); |
e9a25f70 JL |
1066 | no_overflow = 1; |
1067 | break; | |
6d716ca8 | 1068 | |
e9a25f70 JL |
1069 | case RROTATE_EXPR: |
1070 | int2l = - int2l; | |
1071 | case LROTATE_EXPR: | |
4c160717 | 1072 | lrotate_double (int1l, int1h, int2l, TYPE_PRECISION (type), |
e9a25f70 JL |
1073 | &low, &hi); |
1074 | break; | |
6d716ca8 | 1075 | |
e9a25f70 JL |
1076 | case PLUS_EXPR: |
1077 | overflow = add_double (int1l, int1h, int2l, int2h, &low, &hi); | |
1078 | break; | |
6d716ca8 | 1079 | |
e9a25f70 JL |
1080 | case MINUS_EXPR: |
1081 | neg_double (int2l, int2h, &low, &hi); | |
1082 | add_double (int1l, int1h, low, hi, &low, &hi); | |
d4b60170 | 1083 | overflow = OVERFLOW_SUM_SIGN (hi, int2h, int1h); |
e9a25f70 | 1084 | break; |
6d716ca8 | 1085 | |
e9a25f70 JL |
1086 | case MULT_EXPR: |
1087 | overflow = mul_double (int1l, int1h, int2l, int2h, &low, &hi); | |
1088 | break; | |
6d716ca8 | 1089 | |
e9a25f70 JL |
1090 | case TRUNC_DIV_EXPR: |
1091 | case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR: | |
1092 | case EXACT_DIV_EXPR: | |
1093 | /* This is a shortcut for a common special case. */ | |
05bccae2 | 1094 | if (int2h == 0 && (HOST_WIDE_INT) int2l > 0 |
e9a25f70 JL |
1095 | && ! TREE_CONSTANT_OVERFLOW (arg1) |
1096 | && ! TREE_CONSTANT_OVERFLOW (arg2) | |
05bccae2 | 1097 | && int1h == 0 && (HOST_WIDE_INT) int1l >= 0) |
e9a25f70 JL |
1098 | { |
1099 | if (code == CEIL_DIV_EXPR) | |
1100 | int1l += int2l - 1; | |
05bccae2 | 1101 | |
e9a25f70 | 1102 | low = int1l / int2l, hi = 0; |
6d716ca8 | 1103 | break; |
e9a25f70 | 1104 | } |
6d716ca8 | 1105 | |
30f7a378 | 1106 | /* ... fall through ... */ |
6d716ca8 | 1107 | |
b6cc0a72 | 1108 | case ROUND_DIV_EXPR: |
e9a25f70 JL |
1109 | if (int2h == 0 && int2l == 1) |
1110 | { | |
1111 | low = int1l, hi = int1h; | |
6d716ca8 | 1112 | break; |
e9a25f70 JL |
1113 | } |
1114 | if (int1l == int2l && int1h == int2h | |
1115 | && ! (int1l == 0 && int1h == 0)) | |
1116 | { | |
1117 | low = 1, hi = 0; | |
63e7fe9b | 1118 | break; |
e9a25f70 | 1119 | } |
4c160717 | 1120 | overflow = div_and_round_double (code, uns, int1l, int1h, int2l, int2h, |
e9a25f70 JL |
1121 | &low, &hi, &garbagel, &garbageh); |
1122 | break; | |
63e7fe9b | 1123 | |
e9a25f70 JL |
1124 | case TRUNC_MOD_EXPR: |
1125 | case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR: | |
1126 | /* This is a shortcut for a common special case. */ | |
05bccae2 | 1127 | if (int2h == 0 && (HOST_WIDE_INT) int2l > 0 |
e9a25f70 JL |
1128 | && ! TREE_CONSTANT_OVERFLOW (arg1) |
1129 | && ! TREE_CONSTANT_OVERFLOW (arg2) | |
05bccae2 | 1130 | && int1h == 0 && (HOST_WIDE_INT) int1l >= 0) |
e9a25f70 JL |
1131 | { |
1132 | if (code == CEIL_MOD_EXPR) | |
1133 | int1l += int2l - 1; | |
1134 | low = int1l % int2l, hi = 0; | |
63e7fe9b | 1135 | break; |
e9a25f70 | 1136 | } |
63e7fe9b | 1137 | |
30f7a378 | 1138 | /* ... fall through ... */ |
e9a25f70 | 1139 | |
b6cc0a72 | 1140 | case ROUND_MOD_EXPR: |
e9a25f70 JL |
1141 | overflow = div_and_round_double (code, uns, |
1142 | int1l, int1h, int2l, int2h, | |
1143 | &garbagel, &garbageh, &low, &hi); | |
1144 | break; | |
1145 | ||
1146 | case MIN_EXPR: | |
1147 | case MAX_EXPR: | |
1148 | if (uns) | |
d4b60170 RK |
1149 | low = (((unsigned HOST_WIDE_INT) int1h |
1150 | < (unsigned HOST_WIDE_INT) int2h) | |
1151 | || (((unsigned HOST_WIDE_INT) int1h | |
1152 | == (unsigned HOST_WIDE_INT) int2h) | |
05bccae2 | 1153 | && int1l < int2l)); |
380ff34a | 1154 | else |
05bccae2 RK |
1155 | low = (int1h < int2h |
1156 | || (int1h == int2h && int1l < int2l)); | |
d4b60170 | 1157 | |
e9a25f70 JL |
1158 | if (low == (code == MIN_EXPR)) |
1159 | low = int1l, hi = int1h; | |
1160 | else | |
1161 | low = int2l, hi = int2h; | |
1162 | break; | |
3dedc65a | 1163 | |
e9a25f70 JL |
1164 | default: |
1165 | abort (); | |
3dedc65a | 1166 | } |
e9a25f70 | 1167 | |
4c160717 RK |
1168 | /* If this is for a sizetype, can be represented as one (signed) |
1169 | HOST_WIDE_INT word, and doesn't overflow, use size_int since it caches | |
1170 | constants. */ | |
1171 | if (is_sizetype | |
1172 | && ((hi == 0 && (HOST_WIDE_INT) low >= 0) | |
1173 | || (hi == -1 && (HOST_WIDE_INT) low < 0)) | |
44475138 | 1174 | && overflow == 0 && ! TREE_OVERFLOW (arg1) && ! TREE_OVERFLOW (arg2)) |
4c160717 | 1175 | return size_int_type_wide (low, type); |
e9a25f70 JL |
1176 | else |
1177 | { | |
1178 | t = build_int_2 (low, hi); | |
1179 | TREE_TYPE (t) = TREE_TYPE (arg1); | |
1180 | } | |
1181 | ||
1182 | TREE_OVERFLOW (t) | |
4c160717 RK |
1183 | = ((notrunc |
1184 | ? (!uns || is_sizetype) && overflow | |
1185 | : (force_fit_type (t, (!uns || is_sizetype) && overflow) | |
1186 | && ! no_overflow)) | |
e9a25f70 JL |
1187 | | TREE_OVERFLOW (arg1) |
1188 | | TREE_OVERFLOW (arg2)); | |
d4b60170 | 1189 | |
e9a25f70 JL |
1190 | /* If we're doing a size calculation, unsigned arithmetic does overflow. |
1191 | So check if force_fit_type truncated the value. */ | |
4c160717 | 1192 | if (is_sizetype |
e9a25f70 JL |
1193 | && ! TREE_OVERFLOW (t) |
1194 | && (TREE_INT_CST_HIGH (t) != hi | |
1195 | || TREE_INT_CST_LOW (t) != low)) | |
1196 | TREE_OVERFLOW (t) = 1; | |
d4b60170 | 1197 | |
e9a25f70 JL |
1198 | TREE_CONSTANT_OVERFLOW (t) = (TREE_OVERFLOW (t) |
1199 | | TREE_CONSTANT_OVERFLOW (arg1) | |
1200 | | TREE_CONSTANT_OVERFLOW (arg2)); | |
1201 | return t; | |
1202 | } | |
1203 | ||
d4b60170 RK |
1204 | /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new |
1205 | constant. We assume ARG1 and ARG2 have the same data type, or at least | |
1206 | are the same kind of constant and the same machine mode. | |
e9a25f70 JL |
1207 | |
1208 | If NOTRUNC is nonzero, do not truncate the result to fit the data type. */ | |
1209 | ||
1210 | static tree | |
1211 | const_binop (code, arg1, arg2, notrunc) | |
1212 | enum tree_code code; | |
b3694847 | 1213 | tree arg1, arg2; |
e9a25f70 JL |
1214 | int notrunc; |
1215 | { | |
b6cc0a72 KH |
1216 | STRIP_NOPS (arg1); |
1217 | STRIP_NOPS (arg2); | |
e9a25f70 JL |
1218 | |
1219 | if (TREE_CODE (arg1) == INTEGER_CST) | |
4c160717 | 1220 | return int_const_binop (code, arg1, arg2, notrunc); |
e9a25f70 | 1221 | |
6d716ca8 RS |
1222 | if (TREE_CODE (arg1) == REAL_CST) |
1223 | { | |
79c844cd RK |
1224 | REAL_VALUE_TYPE d1; |
1225 | REAL_VALUE_TYPE d2; | |
15e5ad76 | 1226 | REAL_VALUE_TYPE value; |
7c7b029d | 1227 | tree t; |
6d716ca8 | 1228 | |
79c844cd RK |
1229 | d1 = TREE_REAL_CST (arg1); |
1230 | d2 = TREE_REAL_CST (arg2); | |
5f610074 RK |
1231 | |
1232 | /* If either operand is a NaN, just return it. Otherwise, set up | |
1233 | for floating-point trap; we return an overflow. */ | |
1234 | if (REAL_VALUE_ISNAN (d1)) | |
1235 | return arg1; | |
1236 | else if (REAL_VALUE_ISNAN (d2)) | |
1237 | return arg2; | |
a4d3481d | 1238 | |
15e5ad76 | 1239 | REAL_ARITHMETIC (value, code, d1, d2); |
b6cc0a72 | 1240 | |
15e5ad76 ZW |
1241 | t = build_real (TREE_TYPE (arg1), |
1242 | real_value_truncate (TYPE_MODE (TREE_TYPE (arg1)), | |
1243 | value)); | |
649ff3b4 RK |
1244 | |
1245 | TREE_OVERFLOW (t) | |
15e5ad76 | 1246 | = (force_fit_type (t, 0) |
649ff3b4 RK |
1247 | | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2)); |
1248 | TREE_CONSTANT_OVERFLOW (t) | |
1249 | = TREE_OVERFLOW (t) | |
1250 | | TREE_CONSTANT_OVERFLOW (arg1) | |
1251 | | TREE_CONSTANT_OVERFLOW (arg2); | |
7c7b029d | 1252 | return t; |
6d716ca8 | 1253 | } |
6d716ca8 RS |
1254 | if (TREE_CODE (arg1) == COMPLEX_CST) |
1255 | { | |
b3694847 SS |
1256 | tree type = TREE_TYPE (arg1); |
1257 | tree r1 = TREE_REALPART (arg1); | |
1258 | tree i1 = TREE_IMAGPART (arg1); | |
1259 | tree r2 = TREE_REALPART (arg2); | |
1260 | tree i2 = TREE_IMAGPART (arg2); | |
1261 | tree t; | |
6d716ca8 RS |
1262 | |
1263 | switch (code) | |
1264 | { | |
1265 | case PLUS_EXPR: | |
214d5b84 RK |
1266 | t = build_complex (type, |
1267 | const_binop (PLUS_EXPR, r1, r2, notrunc), | |
91d33e36 | 1268 | const_binop (PLUS_EXPR, i1, i2, notrunc)); |
6d716ca8 RS |
1269 | break; |
1270 | ||
1271 | case MINUS_EXPR: | |
214d5b84 RK |
1272 | t = build_complex (type, |
1273 | const_binop (MINUS_EXPR, r1, r2, notrunc), | |
91d33e36 | 1274 | const_binop (MINUS_EXPR, i1, i2, notrunc)); |
6d716ca8 RS |
1275 | break; |
1276 | ||
1277 | case MULT_EXPR: | |
214d5b84 RK |
1278 | t = build_complex (type, |
1279 | const_binop (MINUS_EXPR, | |
91d33e36 RS |
1280 | const_binop (MULT_EXPR, |
1281 | r1, r2, notrunc), | |
1282 | const_binop (MULT_EXPR, | |
1283 | i1, i2, notrunc), | |
1284 | notrunc), | |
6d716ca8 | 1285 | const_binop (PLUS_EXPR, |
91d33e36 RS |
1286 | const_binop (MULT_EXPR, |
1287 | r1, i2, notrunc), | |
1288 | const_binop (MULT_EXPR, | |
1289 | i1, r2, notrunc), | |
1290 | notrunc)); | |
6d716ca8 RS |
1291 | break; |
1292 | ||
1293 | case RDIV_EXPR: | |
1294 | { | |
b3694847 | 1295 | tree magsquared |
6d716ca8 | 1296 | = const_binop (PLUS_EXPR, |
91d33e36 RS |
1297 | const_binop (MULT_EXPR, r2, r2, notrunc), |
1298 | const_binop (MULT_EXPR, i2, i2, notrunc), | |
1299 | notrunc); | |
58633be8 | 1300 | |
214d5b84 RK |
1301 | t = build_complex (type, |
1302 | const_binop | |
1303 | (INTEGRAL_TYPE_P (TREE_TYPE (r1)) | |
1304 | ? TRUNC_DIV_EXPR : RDIV_EXPR, | |
1305 | const_binop (PLUS_EXPR, | |
1306 | const_binop (MULT_EXPR, r1, r2, | |
1307 | notrunc), | |
1308 | const_binop (MULT_EXPR, i1, i2, | |
1309 | notrunc), | |
1310 | notrunc), | |
1311 | magsquared, notrunc), | |
1312 | const_binop | |
1313 | (INTEGRAL_TYPE_P (TREE_TYPE (r1)) | |
1314 | ? TRUNC_DIV_EXPR : RDIV_EXPR, | |
1315 | const_binop (MINUS_EXPR, | |
1316 | const_binop (MULT_EXPR, i1, r2, | |
1317 | notrunc), | |
1318 | const_binop (MULT_EXPR, r1, i2, | |
1319 | notrunc), | |
1320 | notrunc), | |
1321 | magsquared, notrunc)); | |
6d716ca8 RS |
1322 | } |
1323 | break; | |
1324 | ||
1325 | default: | |
1326 | abort (); | |
1327 | } | |
6d716ca8 RS |
1328 | return t; |
1329 | } | |
1330 | return 0; | |
1331 | } | |
4c160717 RK |
1332 | |
1333 | /* These are the hash table functions for the hash table of INTEGER_CST | |
1334 | nodes of a sizetype. */ | |
1335 | ||
1336 | /* Return the hash code code X, an INTEGER_CST. */ | |
1337 | ||
1338 | static hashval_t | |
1339 | size_htab_hash (x) | |
1340 | const void *x; | |
1341 | { | |
1342 | tree t = (tree) x; | |
1343 | ||
1344 | return (TREE_INT_CST_HIGH (t) ^ TREE_INT_CST_LOW (t) | |
1345 | ^ (hashval_t) ((long) TREE_TYPE (t) >> 3) | |
1346 | ^ (TREE_OVERFLOW (t) << 20)); | |
1347 | } | |
1348 | ||
1349 | /* Return non-zero if the value represented by *X (an INTEGER_CST tree node) | |
1350 | is the same as that given by *Y, which is the same. */ | |
1351 | ||
1352 | static int | |
1353 | size_htab_eq (x, y) | |
1354 | const void *x; | |
1355 | const void *y; | |
1356 | { | |
1357 | tree xt = (tree) x; | |
1358 | tree yt = (tree) y; | |
1359 | ||
1360 | return (TREE_INT_CST_HIGH (xt) == TREE_INT_CST_HIGH (yt) | |
1361 | && TREE_INT_CST_LOW (xt) == TREE_INT_CST_LOW (yt) | |
1362 | && TREE_TYPE (xt) == TREE_TYPE (yt) | |
1363 | && TREE_OVERFLOW (xt) == TREE_OVERFLOW (yt)); | |
1364 | } | |
6d716ca8 | 1365 | \f |
06ceef4e | 1366 | /* Return an INTEGER_CST with value whose low-order HOST_BITS_PER_WIDE_INT |
fed3cef0 | 1367 | bits are given by NUMBER and of the sizetype represented by KIND. */ |
d4b60170 | 1368 | |
fed3cef0 RK |
1369 | tree |
1370 | size_int_wide (number, kind) | |
1371 | HOST_WIDE_INT number; | |
1372 | enum size_type_kind kind; | |
1373 | { | |
1374 | return size_int_type_wide (number, sizetype_tab[(int) kind]); | |
1375 | } | |
1376 | ||
1377 | /* Likewise, but the desired type is specified explicitly. */ | |
6d716ca8 | 1378 | |
e2500fed GK |
1379 | static GTY (()) tree new_const; |
1380 | static GTY ((if_marked ("ggc_marked_p"), param_is (union tree_node))) | |
1381 | htab_t size_htab; | |
1382 | ||
6d716ca8 | 1383 | tree |
fed3cef0 | 1384 | size_int_type_wide (number, type) |
06ceef4e | 1385 | HOST_WIDE_INT number; |
fed3cef0 | 1386 | tree type; |
6d716ca8 | 1387 | { |
4c160717 | 1388 | PTR *slot; |
b6cc0a72 | 1389 | |
4c160717 | 1390 | if (size_htab == 0) |
6d716ca8 | 1391 | { |
4c160717 | 1392 | size_htab = htab_create (1024, size_htab_hash, size_htab_eq, NULL); |
4c160717 | 1393 | new_const = make_node (INTEGER_CST); |
d4b60170 RK |
1394 | } |
1395 | ||
4c160717 RK |
1396 | /* Adjust NEW_CONST to be the constant we want. If it's already in the |
1397 | hash table, we return the value from the hash table. Otherwise, we | |
1398 | place that in the hash table and make a new node for the next time. */ | |
1399 | TREE_INT_CST_LOW (new_const) = number; | |
1400 | TREE_INT_CST_HIGH (new_const) = number < 0 ? -1 : 0; | |
1401 | TREE_TYPE (new_const) = type; | |
1402 | TREE_OVERFLOW (new_const) = TREE_CONSTANT_OVERFLOW (new_const) | |
1403 | = force_fit_type (new_const, 0); | |
1404 | ||
1405 | slot = htab_find_slot (size_htab, new_const, INSERT); | |
1406 | if (*slot == 0) | |
d4b60170 | 1407 | { |
4c160717 | 1408 | tree t = new_const; |
d4b60170 | 1409 | |
4c160717 RK |
1410 | *slot = (PTR) new_const; |
1411 | new_const = make_node (INTEGER_CST); | |
d4b60170 | 1412 | return t; |
6d716ca8 | 1413 | } |
4c160717 RK |
1414 | else |
1415 | return (tree) *slot; | |
6d716ca8 RS |
1416 | } |
1417 | ||
fed3cef0 RK |
1418 | /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE |
1419 | is a tree code. The type of the result is taken from the operands. | |
1420 | Both must be the same type integer type and it must be a size type. | |
6d716ca8 RS |
1421 | If the operands are constant, so is the result. */ |
1422 | ||
1423 | tree | |
1424 | size_binop (code, arg0, arg1) | |
1425 | enum tree_code code; | |
1426 | tree arg0, arg1; | |
1427 | { | |
fed3cef0 RK |
1428 | tree type = TREE_TYPE (arg0); |
1429 | ||
21318741 RK |
1430 | if (TREE_CODE (type) != INTEGER_TYPE || ! TYPE_IS_SIZETYPE (type) |
1431 | || type != TREE_TYPE (arg1)) | |
fed3cef0 RK |
1432 | abort (); |
1433 | ||
6d716ca8 RS |
1434 | /* Handle the special case of two integer constants faster. */ |
1435 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) | |
1436 | { | |
1437 | /* And some specific cases even faster than that. */ | |
9898deac | 1438 | if (code == PLUS_EXPR && integer_zerop (arg0)) |
6d716ca8 | 1439 | return arg1; |
9898deac RK |
1440 | else if ((code == MINUS_EXPR || code == PLUS_EXPR) |
1441 | && integer_zerop (arg1)) | |
6d716ca8 | 1442 | return arg0; |
9898deac | 1443 | else if (code == MULT_EXPR && integer_onep (arg0)) |
6d716ca8 | 1444 | return arg1; |
9898deac | 1445 | |
6d716ca8 | 1446 | /* Handle general case of two integer constants. */ |
4c160717 | 1447 | return int_const_binop (code, arg0, arg1, 0); |
6d716ca8 RS |
1448 | } |
1449 | ||
1450 | if (arg0 == error_mark_node || arg1 == error_mark_node) | |
1451 | return error_mark_node; | |
1452 | ||
fed3cef0 | 1453 | return fold (build (code, type, arg0, arg1)); |
6d716ca8 | 1454 | } |
697073d9 | 1455 | |
fed3cef0 RK |
1456 | /* Given two values, either both of sizetype or both of bitsizetype, |
1457 | compute the difference between the two values. Return the value | |
1458 | in signed type corresponding to the type of the operands. */ | |
697073d9 JM |
1459 | |
1460 | tree | |
fed3cef0 | 1461 | size_diffop (arg0, arg1) |
697073d9 JM |
1462 | tree arg0, arg1; |
1463 | { | |
fed3cef0 RK |
1464 | tree type = TREE_TYPE (arg0); |
1465 | tree ctype; | |
697073d9 | 1466 | |
21318741 RK |
1467 | if (TREE_CODE (type) != INTEGER_TYPE || ! TYPE_IS_SIZETYPE (type) |
1468 | || type != TREE_TYPE (arg1)) | |
fed3cef0 | 1469 | abort (); |
697073d9 | 1470 | |
fed3cef0 RK |
1471 | /* If the type is already signed, just do the simple thing. */ |
1472 | if (! TREE_UNSIGNED (type)) | |
1473 | return size_binop (MINUS_EXPR, arg0, arg1); | |
1474 | ||
1475 | ctype = (type == bitsizetype || type == ubitsizetype | |
1476 | ? sbitsizetype : ssizetype); | |
1477 | ||
1478 | /* If either operand is not a constant, do the conversions to the signed | |
1479 | type and subtract. The hardware will do the right thing with any | |
1480 | overflow in the subtraction. */ | |
1481 | if (TREE_CODE (arg0) != INTEGER_CST || TREE_CODE (arg1) != INTEGER_CST) | |
1482 | return size_binop (MINUS_EXPR, convert (ctype, arg0), | |
1483 | convert (ctype, arg1)); | |
1484 | ||
1485 | /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE. | |
1486 | Otherwise, subtract the other way, convert to CTYPE (we know that can't | |
1487 | overflow) and negate (which can't either). Special-case a result | |
1488 | of zero while we're here. */ | |
1489 | if (tree_int_cst_equal (arg0, arg1)) | |
1490 | return convert (ctype, integer_zero_node); | |
1491 | else if (tree_int_cst_lt (arg1, arg0)) | |
1492 | return convert (ctype, size_binop (MINUS_EXPR, arg0, arg1)); | |
1493 | else | |
1494 | return size_binop (MINUS_EXPR, convert (ctype, integer_zero_node), | |
1495 | convert (ctype, size_binop (MINUS_EXPR, arg1, arg0))); | |
697073d9 | 1496 | } |
6d716ca8 | 1497 | \f |
a4d3481d | 1498 | |
6d716ca8 RS |
1499 | /* Given T, a tree representing type conversion of ARG1, a constant, |
1500 | return a constant tree representing the result of conversion. */ | |
1501 | ||
1502 | static tree | |
1503 | fold_convert (t, arg1) | |
b3694847 SS |
1504 | tree t; |
1505 | tree arg1; | |
6d716ca8 | 1506 | { |
b3694847 | 1507 | tree type = TREE_TYPE (t); |
649ff3b4 | 1508 | int overflow = 0; |
6d716ca8 | 1509 | |
e5e809f4 | 1510 | if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)) |
6d716ca8 RS |
1511 | { |
1512 | if (TREE_CODE (arg1) == INTEGER_CST) | |
1513 | { | |
e3374525 RK |
1514 | /* If we would build a constant wider than GCC supports, |
1515 | leave the conversion unfolded. */ | |
1516 | if (TYPE_PRECISION (type) > 2 * HOST_BITS_PER_WIDE_INT) | |
1517 | return t; | |
1518 | ||
fed3cef0 RK |
1519 | /* If we are trying to make a sizetype for a small integer, use |
1520 | size_int to pick up cached types to reduce duplicate nodes. */ | |
55560b9d | 1521 | if (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type) |
ac50176d | 1522 | && !TREE_CONSTANT_OVERFLOW (arg1) |
770ae6cc | 1523 | && compare_tree_int (arg1, 10000) < 0) |
fed3cef0 RK |
1524 | return size_int_type_wide (TREE_INT_CST_LOW (arg1), type); |
1525 | ||
6d716ca8 RS |
1526 | /* Given an integer constant, make new constant with new type, |
1527 | appropriately sign-extended or truncated. */ | |
1528 | t = build_int_2 (TREE_INT_CST_LOW (arg1), | |
1529 | TREE_INT_CST_HIGH (arg1)); | |
1530 | TREE_TYPE (t) = type; | |
e0f776fb | 1531 | /* Indicate an overflow if (1) ARG1 already overflowed, |
dc3907c5 PE |
1532 | or (2) force_fit_type indicates an overflow. |
1533 | Tell force_fit_type that an overflow has already occurred | |
b472527b JL |
1534 | if ARG1 is a too-large unsigned value and T is signed. |
1535 | But don't indicate an overflow if converting a pointer. */ | |
dc3907c5 | 1536 | TREE_OVERFLOW (t) |
e5e809f4 JL |
1537 | = ((force_fit_type (t, |
1538 | (TREE_INT_CST_HIGH (arg1) < 0 | |
4f242db3 | 1539 | && (TREE_UNSIGNED (type) |
e5e809f4 JL |
1540 | < TREE_UNSIGNED (TREE_TYPE (arg1))))) |
1541 | && ! POINTER_TYPE_P (TREE_TYPE (arg1))) | |
1542 | || TREE_OVERFLOW (arg1)); | |
dc3907c5 PE |
1543 | TREE_CONSTANT_OVERFLOW (t) |
1544 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
6d716ca8 | 1545 | } |
6d716ca8 RS |
1546 | else if (TREE_CODE (arg1) == REAL_CST) |
1547 | { | |
4b8a0062 RK |
1548 | /* Don't initialize these, use assignments. |
1549 | Initialized local aggregates don't work on old compilers. */ | |
1550 | REAL_VALUE_TYPE x; | |
1551 | REAL_VALUE_TYPE l; | |
1552 | REAL_VALUE_TYPE u; | |
7cb6a121 | 1553 | tree type1 = TREE_TYPE (arg1); |
e1ee5cdc | 1554 | int no_upper_bound; |
4b8a0062 RK |
1555 | |
1556 | x = TREE_REAL_CST (arg1); | |
7cb6a121 | 1557 | l = real_value_from_int_cst (type1, TYPE_MIN_VALUE (type)); |
e1ee5cdc RH |
1558 | |
1559 | no_upper_bound = (TYPE_MAX_VALUE (type) == NULL); | |
1560 | if (!no_upper_bound) | |
1561 | u = real_value_from_int_cst (type1, TYPE_MAX_VALUE (type)); | |
1562 | ||
4b3d5ea0 RS |
1563 | /* See if X will be in range after truncation towards 0. |
1564 | To compensate for truncation, move the bounds away from 0, | |
1565 | but reject if X exactly equals the adjusted bounds. */ | |
4b3d5ea0 | 1566 | REAL_ARITHMETIC (l, MINUS_EXPR, l, dconst1); |
e1ee5cdc RH |
1567 | if (!no_upper_bound) |
1568 | REAL_ARITHMETIC (u, PLUS_EXPR, u, dconst1); | |
5f610074 RK |
1569 | /* If X is a NaN, use zero instead and show we have an overflow. |
1570 | Otherwise, range check. */ | |
1571 | if (REAL_VALUE_ISNAN (x)) | |
1572 | overflow = 1, x = dconst0; | |
e1ee5cdc RH |
1573 | else if (! (REAL_VALUES_LESS (l, x) |
1574 | && !no_upper_bound | |
1575 | && REAL_VALUES_LESS (x, u))) | |
649ff3b4 RK |
1576 | overflow = 1; |
1577 | ||
6d716ca8 | 1578 | { |
906c4e36 | 1579 | HOST_WIDE_INT low, high; |
5f610074 | 1580 | REAL_VALUE_TO_INT (&low, &high, x); |
6d716ca8 RS |
1581 | t = build_int_2 (low, high); |
1582 | } | |
6d716ca8 | 1583 | TREE_TYPE (t) = type; |
649ff3b4 RK |
1584 | TREE_OVERFLOW (t) |
1585 | = TREE_OVERFLOW (arg1) | force_fit_type (t, overflow); | |
1586 | TREE_CONSTANT_OVERFLOW (t) | |
1587 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
6d716ca8 | 1588 | } |
6d716ca8 RS |
1589 | TREE_TYPE (t) = type; |
1590 | } | |
1591 | else if (TREE_CODE (type) == REAL_TYPE) | |
1592 | { | |
6d716ca8 RS |
1593 | if (TREE_CODE (arg1) == INTEGER_CST) |
1594 | return build_real_from_int_cst (type, arg1); | |
6d716ca8 | 1595 | if (TREE_CODE (arg1) == REAL_CST) |
7c7b029d | 1596 | { |
5f610074 | 1597 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))) |
a377ff85 RK |
1598 | { |
1599 | t = arg1; | |
1600 | TREE_TYPE (arg1) = type; | |
1601 | return t; | |
1602 | } | |
a4d3481d | 1603 | |
15e5ad76 ZW |
1604 | t = build_real (type, |
1605 | real_value_truncate (TYPE_MODE (type), | |
1606 | TREE_REAL_CST (arg1))); | |
649ff3b4 | 1607 | |
649ff3b4 | 1608 | TREE_OVERFLOW (t) |
15e5ad76 | 1609 | = TREE_OVERFLOW (arg1) | force_fit_type (t, 0); |
649ff3b4 RK |
1610 | TREE_CONSTANT_OVERFLOW (t) |
1611 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
7c7b029d RS |
1612 | return t; |
1613 | } | |
6d716ca8 RS |
1614 | } |
1615 | TREE_CONSTANT (t) = 1; | |
1616 | return t; | |
1617 | } | |
1618 | \f | |
ff59bfe6 | 1619 | /* Return an expr equal to X but certainly not valid as an lvalue. */ |
6d716ca8 RS |
1620 | |
1621 | tree | |
1622 | non_lvalue (x) | |
1623 | tree x; | |
1624 | { | |
1625 | tree result; | |
1626 | ||
1627 | /* These things are certainly not lvalues. */ | |
1628 | if (TREE_CODE (x) == NON_LVALUE_EXPR | |
1629 | || TREE_CODE (x) == INTEGER_CST | |
1630 | || TREE_CODE (x) == REAL_CST | |
1631 | || TREE_CODE (x) == STRING_CST | |
1632 | || TREE_CODE (x) == ADDR_EXPR) | |
ff59bfe6 | 1633 | return x; |
6d716ca8 RS |
1634 | |
1635 | result = build1 (NON_LVALUE_EXPR, TREE_TYPE (x), x); | |
1636 | TREE_CONSTANT (result) = TREE_CONSTANT (x); | |
1637 | return result; | |
1638 | } | |
a5e9b124 | 1639 | |
e9866da3 JM |
1640 | /* Nonzero means lvalues are limited to those valid in pedantic ANSI C. |
1641 | Zero means allow extended lvalues. */ | |
1642 | ||
1643 | int pedantic_lvalues; | |
1644 | ||
a5e9b124 JW |
1645 | /* When pedantic, return an expr equal to X but certainly not valid as a |
1646 | pedantic lvalue. Otherwise, return X. */ | |
1647 | ||
1648 | tree | |
1649 | pedantic_non_lvalue (x) | |
1650 | tree x; | |
1651 | { | |
e9866da3 | 1652 | if (pedantic_lvalues) |
a5e9b124 JW |
1653 | return non_lvalue (x); |
1654 | else | |
1655 | return x; | |
1656 | } | |
c05a9b68 RS |
1657 | \f |
1658 | /* Given a tree comparison code, return the code that is the logical inverse | |
1659 | of the given code. It is not safe to do this for floating-point | |
1660 | comparisons, except for NE_EXPR and EQ_EXPR. */ | |
6d716ca8 | 1661 | |
c05a9b68 RS |
1662 | static enum tree_code |
1663 | invert_tree_comparison (code) | |
1664 | enum tree_code code; | |
1665 | { | |
1666 | switch (code) | |
1667 | { | |
1668 | case EQ_EXPR: | |
1669 | return NE_EXPR; | |
1670 | case NE_EXPR: | |
1671 | return EQ_EXPR; | |
1672 | case GT_EXPR: | |
1673 | return LE_EXPR; | |
1674 | case GE_EXPR: | |
1675 | return LT_EXPR; | |
1676 | case LT_EXPR: | |
1677 | return GE_EXPR; | |
1678 | case LE_EXPR: | |
1679 | return GT_EXPR; | |
1680 | default: | |
1681 | abort (); | |
1682 | } | |
1683 | } | |
1684 | ||
1685 | /* Similar, but return the comparison that results if the operands are | |
1686 | swapped. This is safe for floating-point. */ | |
1687 | ||
1688 | static enum tree_code | |
1689 | swap_tree_comparison (code) | |
1690 | enum tree_code code; | |
1691 | { | |
1692 | switch (code) | |
1693 | { | |
1694 | case EQ_EXPR: | |
1695 | case NE_EXPR: | |
1696 | return code; | |
1697 | case GT_EXPR: | |
1698 | return LT_EXPR; | |
1699 | case GE_EXPR: | |
1700 | return LE_EXPR; | |
1701 | case LT_EXPR: | |
1702 | return GT_EXPR; | |
1703 | case LE_EXPR: | |
1704 | return GE_EXPR; | |
1705 | default: | |
1706 | abort (); | |
1707 | } | |
1708 | } | |
61f275ff RK |
1709 | |
1710 | /* Return nonzero if CODE is a tree code that represents a truth value. */ | |
1711 | ||
1712 | static int | |
1713 | truth_value_p (code) | |
1714 | enum tree_code code; | |
1715 | { | |
1716 | return (TREE_CODE_CLASS (code) == '<' | |
1717 | || code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR | |
1718 | || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR | |
1719 | || code == TRUTH_XOR_EXPR || code == TRUTH_NOT_EXPR); | |
1720 | } | |
c05a9b68 | 1721 | \f |
6a1746af RS |
1722 | /* Return nonzero if two operands are necessarily equal. |
1723 | If ONLY_CONST is non-zero, only return non-zero for constants. | |
1724 | This function tests whether the operands are indistinguishable; | |
1725 | it does not test whether they are equal using C's == operation. | |
1726 | The distinction is important for IEEE floating point, because | |
1727 | (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and | |
1728 | (2) two NaNs may be indistinguishable, but NaN!=NaN. */ | |
6d716ca8 RS |
1729 | |
1730 | int | |
1731 | operand_equal_p (arg0, arg1, only_const) | |
1732 | tree arg0, arg1; | |
1733 | int only_const; | |
1734 | { | |
1735 | /* If both types don't have the same signedness, then we can't consider | |
1736 | them equal. We must check this before the STRIP_NOPS calls | |
1737 | because they may change the signedness of the arguments. */ | |
1738 | if (TREE_UNSIGNED (TREE_TYPE (arg0)) != TREE_UNSIGNED (TREE_TYPE (arg1))) | |
1739 | return 0; | |
1740 | ||
1741 | STRIP_NOPS (arg0); | |
1742 | STRIP_NOPS (arg1); | |
1743 | ||
c7cfe938 RK |
1744 | if (TREE_CODE (arg0) != TREE_CODE (arg1) |
1745 | /* This is needed for conversions and for COMPONENT_REF. | |
1746 | Might as well play it safe and always test this. */ | |
e89a9554 ZW |
1747 | || TREE_CODE (TREE_TYPE (arg0)) == ERROR_MARK |
1748 | || TREE_CODE (TREE_TYPE (arg1)) == ERROR_MARK | |
c7cfe938 | 1749 | || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1))) |
6d716ca8 RS |
1750 | return 0; |
1751 | ||
c7cfe938 RK |
1752 | /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal. |
1753 | We don't care about side effects in that case because the SAVE_EXPR | |
1754 | takes care of that for us. In all other cases, two expressions are | |
1755 | equal if they have no side effects. If we have two identical | |
1756 | expressions with side effects that should be treated the same due | |
1757 | to the only side effects being identical SAVE_EXPR's, that will | |
1758 | be detected in the recursive calls below. */ | |
1759 | if (arg0 == arg1 && ! only_const | |
1760 | && (TREE_CODE (arg0) == SAVE_EXPR | |
1761 | || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1)))) | |
6d716ca8 RS |
1762 | return 1; |
1763 | ||
c7cfe938 RK |
1764 | /* Next handle constant cases, those for which we can return 1 even |
1765 | if ONLY_CONST is set. */ | |
1766 | if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1)) | |
1767 | switch (TREE_CODE (arg0)) | |
1768 | { | |
1769 | case INTEGER_CST: | |
3c9b0091 RK |
1770 | return (! TREE_CONSTANT_OVERFLOW (arg0) |
1771 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
05bccae2 | 1772 | && tree_int_cst_equal (arg0, arg1)); |
c7cfe938 RK |
1773 | |
1774 | case REAL_CST: | |
3c9b0091 RK |
1775 | return (! TREE_CONSTANT_OVERFLOW (arg0) |
1776 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
41c9120b PE |
1777 | && REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0), |
1778 | TREE_REAL_CST (arg1))); | |
c7cfe938 | 1779 | |
69ef87e2 AH |
1780 | case VECTOR_CST: |
1781 | { | |
1782 | tree v1, v2; | |
1783 | ||
1784 | if (TREE_CONSTANT_OVERFLOW (arg0) | |
1785 | || TREE_CONSTANT_OVERFLOW (arg1)) | |
1786 | return 0; | |
1787 | ||
1788 | v1 = TREE_VECTOR_CST_ELTS (arg0); | |
1789 | v2 = TREE_VECTOR_CST_ELTS (arg1); | |
1790 | while (v1 && v2) | |
1791 | { | |
1792 | if (!operand_equal_p (v1, v2, only_const)) | |
1793 | return 0; | |
1794 | v1 = TREE_CHAIN (v1); | |
1795 | v2 = TREE_CHAIN (v2); | |
1796 | } | |
1797 | ||
1798 | return 1; | |
1799 | } | |
1800 | ||
c7cfe938 RK |
1801 | case COMPLEX_CST: |
1802 | return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1), | |
1803 | only_const) | |
1804 | && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1), | |
1805 | only_const)); | |
1806 | ||
1807 | case STRING_CST: | |
1808 | return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1) | |
71145810 | 1809 | && ! memcmp (TREE_STRING_POINTER (arg0), |
c7cfe938 RK |
1810 | TREE_STRING_POINTER (arg1), |
1811 | TREE_STRING_LENGTH (arg0))); | |
1812 | ||
1813 | case ADDR_EXPR: | |
1814 | return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), | |
1815 | 0); | |
e9a25f70 JL |
1816 | default: |
1817 | break; | |
c7cfe938 | 1818 | } |
6d716ca8 RS |
1819 | |
1820 | if (only_const) | |
1821 | return 0; | |
1822 | ||
6d716ca8 RS |
1823 | switch (TREE_CODE_CLASS (TREE_CODE (arg0))) |
1824 | { | |
1825 | case '1': | |
1826 | /* Two conversions are equal only if signedness and modes match. */ | |
1827 | if ((TREE_CODE (arg0) == NOP_EXPR || TREE_CODE (arg0) == CONVERT_EXPR) | |
1828 | && (TREE_UNSIGNED (TREE_TYPE (arg0)) | |
1829 | != TREE_UNSIGNED (TREE_TYPE (arg1)))) | |
1830 | return 0; | |
1831 | ||
1832 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
1833 | TREE_OPERAND (arg1, 0), 0); | |
1834 | ||
1835 | case '<': | |
1836 | case '2': | |
c7cfe938 RK |
1837 | if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0) |
1838 | && operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), | |
1839 | 0)) | |
1840 | return 1; | |
1841 | ||
1842 | /* For commutative ops, allow the other order. */ | |
1843 | return ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MULT_EXPR | |
1844 | || TREE_CODE (arg0) == MIN_EXPR || TREE_CODE (arg0) == MAX_EXPR | |
1845 | || TREE_CODE (arg0) == BIT_IOR_EXPR | |
1846 | || TREE_CODE (arg0) == BIT_XOR_EXPR | |
1847 | || TREE_CODE (arg0) == BIT_AND_EXPR | |
1848 | || TREE_CODE (arg0) == NE_EXPR || TREE_CODE (arg0) == EQ_EXPR) | |
1849 | && operand_equal_p (TREE_OPERAND (arg0, 0), | |
1850 | TREE_OPERAND (arg1, 1), 0) | |
6d716ca8 | 1851 | && operand_equal_p (TREE_OPERAND (arg0, 1), |
c7cfe938 | 1852 | TREE_OPERAND (arg1, 0), 0)); |
6d716ca8 RS |
1853 | |
1854 | case 'r': | |
05ca5990 | 1855 | /* If either of the pointer (or reference) expressions we are dereferencing |
30f7a378 | 1856 | contain a side effect, these cannot be equal. */ |
05ca5990 GRK |
1857 | if (TREE_SIDE_EFFECTS (arg0) |
1858 | || TREE_SIDE_EFFECTS (arg1)) | |
1859 | return 0; | |
1860 | ||
6d716ca8 RS |
1861 | switch (TREE_CODE (arg0)) |
1862 | { | |
1863 | case INDIRECT_REF: | |
1864 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
1865 | TREE_OPERAND (arg1, 0), 0); | |
1866 | ||
1867 | case COMPONENT_REF: | |
1868 | case ARRAY_REF: | |
b4e3fabb | 1869 | case ARRAY_RANGE_REF: |
6d716ca8 RS |
1870 | return (operand_equal_p (TREE_OPERAND (arg0, 0), |
1871 | TREE_OPERAND (arg1, 0), 0) | |
1872 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
1873 | TREE_OPERAND (arg1, 1), 0)); | |
1874 | ||
1875 | case BIT_FIELD_REF: | |
1876 | return (operand_equal_p (TREE_OPERAND (arg0, 0), | |
1877 | TREE_OPERAND (arg1, 0), 0) | |
1878 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
1879 | TREE_OPERAND (arg1, 1), 0) | |
1880 | && operand_equal_p (TREE_OPERAND (arg0, 2), | |
1881 | TREE_OPERAND (arg1, 2), 0)); | |
e9a25f70 JL |
1882 | default: |
1883 | return 0; | |
6d716ca8 | 1884 | } |
45f97e2e RH |
1885 | |
1886 | case 'e': | |
1887 | if (TREE_CODE (arg0) == RTL_EXPR) | |
1888 | return rtx_equal_p (RTL_EXPR_RTL (arg0), RTL_EXPR_RTL (arg1)); | |
1889 | return 0; | |
b6cc0a72 | 1890 | |
e9a25f70 JL |
1891 | default: |
1892 | return 0; | |
6d716ca8 | 1893 | } |
6d716ca8 | 1894 | } |
c05a9b68 RS |
1895 | \f |
1896 | /* Similar to operand_equal_p, but see if ARG0 might have been made by | |
b6cc0a72 | 1897 | shorten_compare from ARG1 when ARG1 was being compared with OTHER. |
6d716ca8 | 1898 | |
6d716ca8 RS |
1899 | When in doubt, return 0. */ |
1900 | ||
b6cc0a72 | 1901 | static int |
c05a9b68 RS |
1902 | operand_equal_for_comparison_p (arg0, arg1, other) |
1903 | tree arg0, arg1; | |
1904 | tree other; | |
6d716ca8 | 1905 | { |
c05a9b68 | 1906 | int unsignedp1, unsignedpo; |
52de9b6c | 1907 | tree primarg0, primarg1, primother; |
770ae6cc | 1908 | unsigned int correct_width; |
6d716ca8 | 1909 | |
c05a9b68 | 1910 | if (operand_equal_p (arg0, arg1, 0)) |
6d716ca8 RS |
1911 | return 1; |
1912 | ||
0982a4b8 JM |
1913 | if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0)) |
1914 | || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1))) | |
6d716ca8 RS |
1915 | return 0; |
1916 | ||
52de9b6c RK |
1917 | /* Discard any conversions that don't change the modes of ARG0 and ARG1 |
1918 | and see if the inner values are the same. This removes any | |
1919 | signedness comparison, which doesn't matter here. */ | |
1920 | primarg0 = arg0, primarg1 = arg1; | |
b6cc0a72 KH |
1921 | STRIP_NOPS (primarg0); |
1922 | STRIP_NOPS (primarg1); | |
52de9b6c RK |
1923 | if (operand_equal_p (primarg0, primarg1, 0)) |
1924 | return 1; | |
1925 | ||
c05a9b68 RS |
1926 | /* Duplicate what shorten_compare does to ARG1 and see if that gives the |
1927 | actual comparison operand, ARG0. | |
6d716ca8 | 1928 | |
c05a9b68 | 1929 | First throw away any conversions to wider types |
6d716ca8 | 1930 | already present in the operands. */ |
6d716ca8 | 1931 | |
c05a9b68 RS |
1932 | primarg1 = get_narrower (arg1, &unsignedp1); |
1933 | primother = get_narrower (other, &unsignedpo); | |
1934 | ||
1935 | correct_width = TYPE_PRECISION (TREE_TYPE (arg1)); | |
1936 | if (unsignedp1 == unsignedpo | |
1937 | && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width | |
1938 | && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width) | |
6d716ca8 | 1939 | { |
c05a9b68 | 1940 | tree type = TREE_TYPE (arg0); |
6d716ca8 RS |
1941 | |
1942 | /* Make sure shorter operand is extended the right way | |
1943 | to match the longer operand. */ | |
ceef8ce4 NB |
1944 | primarg1 = convert ((*lang_hooks.types.signed_or_unsigned_type) |
1945 | (unsignedp1, TREE_TYPE (primarg1)), primarg1); | |
6d716ca8 | 1946 | |
c05a9b68 | 1947 | if (operand_equal_p (arg0, convert (type, primarg1), 0)) |
6d716ca8 RS |
1948 | return 1; |
1949 | } | |
1950 | ||
1951 | return 0; | |
1952 | } | |
1953 | \f | |
f72aed24 | 1954 | /* See if ARG is an expression that is either a comparison or is performing |
c05a9b68 RS |
1955 | arithmetic on comparisons. The comparisons must only be comparing |
1956 | two different values, which will be stored in *CVAL1 and *CVAL2; if | |
1957 | they are non-zero it means that some operands have already been found. | |
1958 | No variables may be used anywhere else in the expression except in the | |
35e66bd1 RK |
1959 | comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around |
1960 | the expression and save_expr needs to be called with CVAL1 and CVAL2. | |
c05a9b68 RS |
1961 | |
1962 | If this is true, return 1. Otherwise, return zero. */ | |
1963 | ||
1964 | static int | |
35e66bd1 | 1965 | twoval_comparison_p (arg, cval1, cval2, save_p) |
c05a9b68 RS |
1966 | tree arg; |
1967 | tree *cval1, *cval2; | |
35e66bd1 | 1968 | int *save_p; |
c05a9b68 RS |
1969 | { |
1970 | enum tree_code code = TREE_CODE (arg); | |
1971 | char class = TREE_CODE_CLASS (code); | |
1972 | ||
1973 | /* We can handle some of the 'e' cases here. */ | |
35e66bd1 | 1974 | if (class == 'e' && code == TRUTH_NOT_EXPR) |
c05a9b68 RS |
1975 | class = '1'; |
1976 | else if (class == 'e' | |
1977 | && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR | |
1978 | || code == COMPOUND_EXPR)) | |
1979 | class = '2'; | |
2315a5db | 1980 | |
d4b60170 RK |
1981 | else if (class == 'e' && code == SAVE_EXPR && SAVE_EXPR_RTL (arg) == 0 |
1982 | && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0))) | |
35e66bd1 RK |
1983 | { |
1984 | /* If we've already found a CVAL1 or CVAL2, this expression is | |
1985 | two complex to handle. */ | |
1986 | if (*cval1 || *cval2) | |
1987 | return 0; | |
1988 | ||
1989 | class = '1'; | |
1990 | *save_p = 1; | |
1991 | } | |
c05a9b68 RS |
1992 | |
1993 | switch (class) | |
1994 | { | |
1995 | case '1': | |
35e66bd1 | 1996 | return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p); |
c05a9b68 RS |
1997 | |
1998 | case '2': | |
35e66bd1 RK |
1999 | return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p) |
2000 | && twoval_comparison_p (TREE_OPERAND (arg, 1), | |
2001 | cval1, cval2, save_p)); | |
c05a9b68 RS |
2002 | |
2003 | case 'c': | |
2004 | return 1; | |
2005 | ||
2006 | case 'e': | |
2007 | if (code == COND_EXPR) | |
35e66bd1 RK |
2008 | return (twoval_comparison_p (TREE_OPERAND (arg, 0), |
2009 | cval1, cval2, save_p) | |
2010 | && twoval_comparison_p (TREE_OPERAND (arg, 1), | |
2011 | cval1, cval2, save_p) | |
c05a9b68 | 2012 | && twoval_comparison_p (TREE_OPERAND (arg, 2), |
35e66bd1 | 2013 | cval1, cval2, save_p)); |
c05a9b68 | 2014 | return 0; |
b6cc0a72 | 2015 | |
c05a9b68 RS |
2016 | case '<': |
2017 | /* First see if we can handle the first operand, then the second. For | |
2018 | the second operand, we know *CVAL1 can't be zero. It must be that | |
2019 | one side of the comparison is each of the values; test for the | |
2020 | case where this isn't true by failing if the two operands | |
2021 | are the same. */ | |
2022 | ||
2023 | if (operand_equal_p (TREE_OPERAND (arg, 0), | |
2024 | TREE_OPERAND (arg, 1), 0)) | |
2025 | return 0; | |
2026 | ||
2027 | if (*cval1 == 0) | |
2028 | *cval1 = TREE_OPERAND (arg, 0); | |
2029 | else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0)) | |
2030 | ; | |
2031 | else if (*cval2 == 0) | |
2032 | *cval2 = TREE_OPERAND (arg, 0); | |
2033 | else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0)) | |
2034 | ; | |
2035 | else | |
2036 | return 0; | |
2037 | ||
2038 | if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0)) | |
2039 | ; | |
2040 | else if (*cval2 == 0) | |
2041 | *cval2 = TREE_OPERAND (arg, 1); | |
2042 | else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0)) | |
2043 | ; | |
2044 | else | |
2045 | return 0; | |
2046 | ||
2047 | return 1; | |
c05a9b68 | 2048 | |
e9a25f70 JL |
2049 | default: |
2050 | return 0; | |
2051 | } | |
c05a9b68 RS |
2052 | } |
2053 | \f | |
2054 | /* ARG is a tree that is known to contain just arithmetic operations and | |
2055 | comparisons. Evaluate the operations in the tree substituting NEW0 for | |
f72aed24 | 2056 | any occurrence of OLD0 as an operand of a comparison and likewise for |
c05a9b68 RS |
2057 | NEW1 and OLD1. */ |
2058 | ||
2059 | static tree | |
2060 | eval_subst (arg, old0, new0, old1, new1) | |
2061 | tree arg; | |
2062 | tree old0, new0, old1, new1; | |
2063 | { | |
2064 | tree type = TREE_TYPE (arg); | |
2065 | enum tree_code code = TREE_CODE (arg); | |
2066 | char class = TREE_CODE_CLASS (code); | |
2067 | ||
2068 | /* We can handle some of the 'e' cases here. */ | |
2069 | if (class == 'e' && code == TRUTH_NOT_EXPR) | |
2070 | class = '1'; | |
2071 | else if (class == 'e' | |
2072 | && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)) | |
2073 | class = '2'; | |
2074 | ||
2075 | switch (class) | |
2076 | { | |
2077 | case '1': | |
2078 | return fold (build1 (code, type, | |
2079 | eval_subst (TREE_OPERAND (arg, 0), | |
2080 | old0, new0, old1, new1))); | |
2081 | ||
2082 | case '2': | |
2083 | return fold (build (code, type, | |
2084 | eval_subst (TREE_OPERAND (arg, 0), | |
2085 | old0, new0, old1, new1), | |
2086 | eval_subst (TREE_OPERAND (arg, 1), | |
2087 | old0, new0, old1, new1))); | |
2088 | ||
2089 | case 'e': | |
2090 | switch (code) | |
2091 | { | |
2092 | case SAVE_EXPR: | |
2093 | return eval_subst (TREE_OPERAND (arg, 0), old0, new0, old1, new1); | |
2094 | ||
2095 | case COMPOUND_EXPR: | |
2096 | return eval_subst (TREE_OPERAND (arg, 1), old0, new0, old1, new1); | |
2097 | ||
2098 | case COND_EXPR: | |
2099 | return fold (build (code, type, | |
2100 | eval_subst (TREE_OPERAND (arg, 0), | |
2101 | old0, new0, old1, new1), | |
2102 | eval_subst (TREE_OPERAND (arg, 1), | |
2103 | old0, new0, old1, new1), | |
2104 | eval_subst (TREE_OPERAND (arg, 2), | |
2105 | old0, new0, old1, new1))); | |
e9a25f70 JL |
2106 | default: |
2107 | break; | |
c05a9b68 | 2108 | } |
e45ed4de | 2109 | /* fall through - ??? */ |
c05a9b68 RS |
2110 | |
2111 | case '<': | |
2112 | { | |
2113 | tree arg0 = TREE_OPERAND (arg, 0); | |
2114 | tree arg1 = TREE_OPERAND (arg, 1); | |
2115 | ||
2116 | /* We need to check both for exact equality and tree equality. The | |
2117 | former will be true if the operand has a side-effect. In that | |
2118 | case, we know the operand occurred exactly once. */ | |
2119 | ||
2120 | if (arg0 == old0 || operand_equal_p (arg0, old0, 0)) | |
2121 | arg0 = new0; | |
2122 | else if (arg0 == old1 || operand_equal_p (arg0, old1, 0)) | |
2123 | arg0 = new1; | |
2124 | ||
2125 | if (arg1 == old0 || operand_equal_p (arg1, old0, 0)) | |
2126 | arg1 = new0; | |
2127 | else if (arg1 == old1 || operand_equal_p (arg1, old1, 0)) | |
2128 | arg1 = new1; | |
2129 | ||
2130 | return fold (build (code, type, arg0, arg1)); | |
2131 | } | |
c05a9b68 | 2132 | |
e9a25f70 JL |
2133 | default: |
2134 | return arg; | |
2135 | } | |
c05a9b68 RS |
2136 | } |
2137 | \f | |
6d716ca8 RS |
2138 | /* Return a tree for the case when the result of an expression is RESULT |
2139 | converted to TYPE and OMITTED was previously an operand of the expression | |
2140 | but is now not needed (e.g., we folded OMITTED * 0). | |
2141 | ||
2142 | If OMITTED has side effects, we must evaluate it. Otherwise, just do | |
2143 | the conversion of RESULT to TYPE. */ | |
2144 | ||
2145 | static tree | |
2146 | omit_one_operand (type, result, omitted) | |
2147 | tree type, result, omitted; | |
2148 | { | |
2149 | tree t = convert (type, result); | |
2150 | ||
2151 | if (TREE_SIDE_EFFECTS (omitted)) | |
2152 | return build (COMPOUND_EXPR, type, omitted, t); | |
2153 | ||
d023bff9 | 2154 | return non_lvalue (t); |
6d716ca8 | 2155 | } |
4ab3cb65 RK |
2156 | |
2157 | /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */ | |
2158 | ||
2159 | static tree | |
2160 | pedantic_omit_one_operand (type, result, omitted) | |
2161 | tree type, result, omitted; | |
2162 | { | |
2163 | tree t = convert (type, result); | |
2164 | ||
2165 | if (TREE_SIDE_EFFECTS (omitted)) | |
2166 | return build (COMPOUND_EXPR, type, omitted, t); | |
2167 | ||
2168 | return pedantic_non_lvalue (t); | |
2169 | } | |
6d716ca8 | 2170 | \f |
3f783329 RS |
2171 | /* Return a simplified tree node for the truth-negation of ARG. This |
2172 | never alters ARG itself. We assume that ARG is an operation that | |
6d716ca8 RS |
2173 | returns a truth value (0 or 1). */ |
2174 | ||
2175 | tree | |
2176 | invert_truthvalue (arg) | |
2177 | tree arg; | |
2178 | { | |
2179 | tree type = TREE_TYPE (arg); | |
c05a9b68 | 2180 | enum tree_code code = TREE_CODE (arg); |
6d716ca8 | 2181 | |
8ac1abdf JW |
2182 | if (code == ERROR_MARK) |
2183 | return arg; | |
2184 | ||
c05a9b68 RS |
2185 | /* If this is a comparison, we can simply invert it, except for |
2186 | floating-point non-equality comparisons, in which case we just | |
2187 | enclose a TRUTH_NOT_EXPR around what we have. */ | |
6d716ca8 | 2188 | |
c05a9b68 | 2189 | if (TREE_CODE_CLASS (code) == '<') |
6d716ca8 | 2190 | { |
7178e3af | 2191 | if (FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg, 0))) |
de6c5979 | 2192 | && !flag_unsafe_math_optimizations |
dd3f0101 | 2193 | && code != NE_EXPR |
de6c5979 | 2194 | && code != EQ_EXPR) |
c05a9b68 RS |
2195 | return build1 (TRUTH_NOT_EXPR, type, arg); |
2196 | else | |
ca46db87 | 2197 | return build (invert_tree_comparison (code), type, |
3f783329 | 2198 | TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1)); |
c05a9b68 | 2199 | } |
6d716ca8 | 2200 | |
c05a9b68 RS |
2201 | switch (code) |
2202 | { | |
6d716ca8 | 2203 | case INTEGER_CST: |
05bccae2 | 2204 | return convert (type, build_int_2 (integer_zerop (arg), 0)); |
6d716ca8 RS |
2205 | |
2206 | case TRUTH_AND_EXPR: | |
2207 | return build (TRUTH_OR_EXPR, type, | |
2208 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2209 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2210 | ||
2211 | case TRUTH_OR_EXPR: | |
2212 | return build (TRUTH_AND_EXPR, type, | |
2213 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2214 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2215 | ||
772447c5 RK |
2216 | case TRUTH_XOR_EXPR: |
2217 | /* Here we can invert either operand. We invert the first operand | |
2218 | unless the second operand is a TRUTH_NOT_EXPR in which case our | |
2219 | result is the XOR of the first operand with the inside of the | |
2220 | negation of the second operand. */ | |
2221 | ||
2222 | if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR) | |
2223 | return build (TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0), | |
2224 | TREE_OPERAND (TREE_OPERAND (arg, 1), 0)); | |
2225 | else | |
2226 | return build (TRUTH_XOR_EXPR, type, | |
2227 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2228 | TREE_OPERAND (arg, 1)); | |
2229 | ||
6d716ca8 RS |
2230 | case TRUTH_ANDIF_EXPR: |
2231 | return build (TRUTH_ORIF_EXPR, type, | |
2232 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2233 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2234 | ||
2235 | case TRUTH_ORIF_EXPR: | |
2236 | return build (TRUTH_ANDIF_EXPR, type, | |
2237 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2238 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2239 | ||
2240 | case TRUTH_NOT_EXPR: | |
2241 | return TREE_OPERAND (arg, 0); | |
2242 | ||
2243 | case COND_EXPR: | |
2244 | return build (COND_EXPR, type, TREE_OPERAND (arg, 0), | |
2245 | invert_truthvalue (TREE_OPERAND (arg, 1)), | |
2246 | invert_truthvalue (TREE_OPERAND (arg, 2))); | |
2247 | ||
ef9fe0da RK |
2248 | case COMPOUND_EXPR: |
2249 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg, 0), | |
2250 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2251 | ||
14a774a9 RK |
2252 | case WITH_RECORD_EXPR: |
2253 | return build (WITH_RECORD_EXPR, type, | |
2254 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2255 | TREE_OPERAND (arg, 1)); | |
2256 | ||
6d716ca8 RS |
2257 | case NON_LVALUE_EXPR: |
2258 | return invert_truthvalue (TREE_OPERAND (arg, 0)); | |
2259 | ||
2260 | case NOP_EXPR: | |
2261 | case CONVERT_EXPR: | |
2262 | case FLOAT_EXPR: | |
2263 | return build1 (TREE_CODE (arg), type, | |
2264 | invert_truthvalue (TREE_OPERAND (arg, 0))); | |
2265 | ||
2266 | case BIT_AND_EXPR: | |
efc1a4d9 PB |
2267 | if (!integer_onep (TREE_OPERAND (arg, 1))) |
2268 | break; | |
6d716ca8 | 2269 | return build (EQ_EXPR, type, arg, convert (type, integer_zero_node)); |
6d716ca8 | 2270 | |
dfa90b42 RS |
2271 | case SAVE_EXPR: |
2272 | return build1 (TRUTH_NOT_EXPR, type, arg); | |
a25ee332 RK |
2273 | |
2274 | case CLEANUP_POINT_EXPR: | |
2275 | return build1 (CLEANUP_POINT_EXPR, type, | |
2276 | invert_truthvalue (TREE_OPERAND (arg, 0))); | |
e9a25f70 JL |
2277 | |
2278 | default: | |
2279 | break; | |
efc1a4d9 PB |
2280 | } |
2281 | if (TREE_CODE (TREE_TYPE (arg)) != BOOLEAN_TYPE) | |
dfa90b42 | 2282 | abort (); |
efc1a4d9 | 2283 | return build1 (TRUTH_NOT_EXPR, type, arg); |
6d716ca8 RS |
2284 | } |
2285 | ||
2286 | /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both | |
2287 | operands are another bit-wise operation with a common input. If so, | |
2288 | distribute the bit operations to save an operation and possibly two if | |
2289 | constants are involved. For example, convert | |
2290 | (A | B) & (A | C) into A | (B & C) | |
2291 | Further simplification will occur if B and C are constants. | |
2292 | ||
2293 | If this optimization cannot be done, 0 will be returned. */ | |
2294 | ||
2295 | static tree | |
2296 | distribute_bit_expr (code, type, arg0, arg1) | |
2297 | enum tree_code code; | |
2298 | tree type; | |
2299 | tree arg0, arg1; | |
2300 | { | |
2301 | tree common; | |
2302 | tree left, right; | |
2303 | ||
2304 | if (TREE_CODE (arg0) != TREE_CODE (arg1) | |
2305 | || TREE_CODE (arg0) == code | |
fced8ba3 RS |
2306 | || (TREE_CODE (arg0) != BIT_AND_EXPR |
2307 | && TREE_CODE (arg0) != BIT_IOR_EXPR)) | |
6d716ca8 RS |
2308 | return 0; |
2309 | ||
2310 | if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0)) | |
2311 | { | |
2312 | common = TREE_OPERAND (arg0, 0); | |
2313 | left = TREE_OPERAND (arg0, 1); | |
2314 | right = TREE_OPERAND (arg1, 1); | |
2315 | } | |
2316 | else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0)) | |
2317 | { | |
2318 | common = TREE_OPERAND (arg0, 0); | |
2319 | left = TREE_OPERAND (arg0, 1); | |
2320 | right = TREE_OPERAND (arg1, 0); | |
2321 | } | |
2322 | else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0)) | |
2323 | { | |
2324 | common = TREE_OPERAND (arg0, 1); | |
2325 | left = TREE_OPERAND (arg0, 0); | |
2326 | right = TREE_OPERAND (arg1, 1); | |
2327 | } | |
2328 | else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0)) | |
2329 | { | |
2330 | common = TREE_OPERAND (arg0, 1); | |
2331 | left = TREE_OPERAND (arg0, 0); | |
2332 | right = TREE_OPERAND (arg1, 0); | |
2333 | } | |
2334 | else | |
2335 | return 0; | |
2336 | ||
2337 | return fold (build (TREE_CODE (arg0), type, common, | |
2338 | fold (build (code, type, left, right)))); | |
2339 | } | |
2340 | \f | |
2341 | /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER | |
2342 | starting at BITPOS. The field is unsigned if UNSIGNEDP is non-zero. */ | |
2343 | ||
2344 | static tree | |
2345 | make_bit_field_ref (inner, type, bitsize, bitpos, unsignedp) | |
2346 | tree inner; | |
2347 | tree type; | |
2348 | int bitsize, bitpos; | |
2349 | int unsignedp; | |
2350 | { | |
2351 | tree result = build (BIT_FIELD_REF, type, inner, | |
06ceef4e | 2352 | size_int (bitsize), bitsize_int (bitpos)); |
6d716ca8 RS |
2353 | |
2354 | TREE_UNSIGNED (result) = unsignedp; | |
2355 | ||
2356 | return result; | |
2357 | } | |
2358 | ||
2359 | /* Optimize a bit-field compare. | |
2360 | ||
2361 | There are two cases: First is a compare against a constant and the | |
2362 | second is a comparison of two items where the fields are at the same | |
2363 | bit position relative to the start of a chunk (byte, halfword, word) | |
2364 | large enough to contain it. In these cases we can avoid the shift | |
2365 | implicit in bitfield extractions. | |
2366 | ||
2367 | For constants, we emit a compare of the shifted constant with the | |
2368 | BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being | |
2369 | compared. For two fields at the same position, we do the ANDs with the | |
2370 | similar mask and compare the result of the ANDs. | |
2371 | ||
2372 | CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR. | |
2373 | COMPARE_TYPE is the type of the comparison, and LHS and RHS | |
2374 | are the left and right operands of the comparison, respectively. | |
2375 | ||
6dc42e49 | 2376 | If the optimization described above can be done, we return the resulting |
6d716ca8 RS |
2377 | tree. Otherwise we return zero. */ |
2378 | ||
2379 | static tree | |
2380 | optimize_bit_field_compare (code, compare_type, lhs, rhs) | |
2381 | enum tree_code code; | |
2382 | tree compare_type; | |
2383 | tree lhs, rhs; | |
2384 | { | |
770ae6cc | 2385 | HOST_WIDE_INT lbitpos, lbitsize, rbitpos, rbitsize, nbitpos, nbitsize; |
6d716ca8 RS |
2386 | tree type = TREE_TYPE (lhs); |
2387 | tree signed_type, unsigned_type; | |
2388 | int const_p = TREE_CODE (rhs) == INTEGER_CST; | |
5826cacf | 2389 | enum machine_mode lmode, rmode, nmode; |
6d716ca8 RS |
2390 | int lunsignedp, runsignedp; |
2391 | int lvolatilep = 0, rvolatilep = 0; | |
4e86caed | 2392 | tree linner, rinner = NULL_TREE; |
6d716ca8 | 2393 | tree mask; |
f1e60ec6 | 2394 | tree offset; |
6d716ca8 RS |
2395 | |
2396 | /* Get all the information about the extractions being done. If the bit size | |
2397 | if the same as the size of the underlying object, we aren't doing an | |
14a774a9 RK |
2398 | extraction at all and so can do nothing. We also don't want to |
2399 | do anything if the inner expression is a PLACEHOLDER_EXPR since we | |
2400 | then will no longer be able to replace it. */ | |
f1e60ec6 | 2401 | linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode, |
a06ef755 | 2402 | &lunsignedp, &lvolatilep); |
9f5e873c | 2403 | if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0 |
14a774a9 | 2404 | || offset != 0 || TREE_CODE (linner) == PLACEHOLDER_EXPR) |
6d716ca8 RS |
2405 | return 0; |
2406 | ||
2407 | if (!const_p) | |
2408 | { | |
2409 | /* If this is not a constant, we can only do something if bit positions, | |
6d2f8887 | 2410 | sizes, and signedness are the same. */ |
23bd99ae | 2411 | rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode, |
a06ef755 | 2412 | &runsignedp, &rvolatilep); |
6d716ca8 | 2413 | |
9f5e873c | 2414 | if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize |
14a774a9 RK |
2415 | || lunsignedp != runsignedp || offset != 0 |
2416 | || TREE_CODE (rinner) == PLACEHOLDER_EXPR) | |
6d716ca8 RS |
2417 | return 0; |
2418 | } | |
2419 | ||
2420 | /* See if we can find a mode to refer to this field. We should be able to, | |
2421 | but fail if we can't. */ | |
5826cacf RK |
2422 | nmode = get_best_mode (lbitsize, lbitpos, |
2423 | const_p ? TYPE_ALIGN (TREE_TYPE (linner)) | |
2424 | : MIN (TYPE_ALIGN (TREE_TYPE (linner)), | |
2425 | TYPE_ALIGN (TREE_TYPE (rinner))), | |
2426 | word_mode, lvolatilep || rvolatilep); | |
2427 | if (nmode == VOIDmode) | |
6d716ca8 RS |
2428 | return 0; |
2429 | ||
2430 | /* Set signed and unsigned types of the precision of this mode for the | |
2431 | shifts below. */ | |
b0c48229 NB |
2432 | signed_type = (*lang_hooks.types.type_for_mode) (nmode, 0); |
2433 | unsigned_type = (*lang_hooks.types.type_for_mode) (nmode, 1); | |
6d716ca8 | 2434 | |
6d716ca8 RS |
2435 | /* Compute the bit position and size for the new reference and our offset |
2436 | within it. If the new reference is the same size as the original, we | |
2437 | won't optimize anything, so return zero. */ | |
5826cacf RK |
2438 | nbitsize = GET_MODE_BITSIZE (nmode); |
2439 | nbitpos = lbitpos & ~ (nbitsize - 1); | |
2440 | lbitpos -= nbitpos; | |
2441 | if (nbitsize == lbitsize) | |
6d716ca8 RS |
2442 | return 0; |
2443 | ||
f76b9db2 | 2444 | if (BYTES_BIG_ENDIAN) |
5826cacf | 2445 | lbitpos = nbitsize - lbitsize - lbitpos; |
6d716ca8 RS |
2446 | |
2447 | /* Make the mask to be used against the extracted field. */ | |
13af526d RS |
2448 | mask = build_int_2 (~0, ~0); |
2449 | TREE_TYPE (mask) = unsigned_type; | |
aa830baf | 2450 | force_fit_type (mask, 0); |
13af526d | 2451 | mask = convert (unsigned_type, mask); |
5826cacf | 2452 | mask = const_binop (LSHIFT_EXPR, mask, size_int (nbitsize - lbitsize), 0); |
6d716ca8 | 2453 | mask = const_binop (RSHIFT_EXPR, mask, |
5826cacf | 2454 | size_int (nbitsize - lbitsize - lbitpos), 0); |
6d716ca8 RS |
2455 | |
2456 | if (! const_p) | |
2457 | /* If not comparing with constant, just rework the comparison | |
2458 | and return. */ | |
2459 | return build (code, compare_type, | |
c0b9d4c8 RK |
2460 | build (BIT_AND_EXPR, unsigned_type, |
2461 | make_bit_field_ref (linner, unsigned_type, | |
5826cacf | 2462 | nbitsize, nbitpos, 1), |
6d716ca8 | 2463 | mask), |
c0b9d4c8 RK |
2464 | build (BIT_AND_EXPR, unsigned_type, |
2465 | make_bit_field_ref (rinner, unsigned_type, | |
5826cacf | 2466 | nbitsize, nbitpos, 1), |
6d716ca8 RS |
2467 | mask)); |
2468 | ||
2469 | /* Otherwise, we are handling the constant case. See if the constant is too | |
2470 | big for the field. Warn and return a tree of for 0 (false) if so. We do | |
2471 | this not only for its own sake, but to avoid having to test for this | |
2472 | error case below. If we didn't, we might generate wrong code. | |
2473 | ||
2474 | For unsigned fields, the constant shifted right by the field length should | |
b6cc0a72 | 2475 | be all zero. For signed fields, the high-order bits should agree with |
6d716ca8 RS |
2476 | the sign bit. */ |
2477 | ||
2478 | if (lunsignedp) | |
2479 | { | |
2480 | if (! integer_zerop (const_binop (RSHIFT_EXPR, | |
2481 | convert (unsigned_type, rhs), | |
91d33e36 | 2482 | size_int (lbitsize), 0))) |
6d716ca8 | 2483 | { |
b0287a90 | 2484 | warning ("comparison is always %d due to width of bit-field", |
ab87f8c8 | 2485 | code == NE_EXPR); |
6d716ca8 RS |
2486 | return convert (compare_type, |
2487 | (code == NE_EXPR | |
2488 | ? integer_one_node : integer_zero_node)); | |
2489 | } | |
2490 | } | |
2491 | else | |
2492 | { | |
2493 | tree tem = const_binop (RSHIFT_EXPR, convert (signed_type, rhs), | |
91d33e36 | 2494 | size_int (lbitsize - 1), 0); |
6d716ca8 RS |
2495 | if (! integer_zerop (tem) && ! integer_all_onesp (tem)) |
2496 | { | |
b0287a90 | 2497 | warning ("comparison is always %d due to width of bit-field", |
ab87f8c8 | 2498 | code == NE_EXPR); |
6d716ca8 RS |
2499 | return convert (compare_type, |
2500 | (code == NE_EXPR | |
2501 | ? integer_one_node : integer_zero_node)); | |
2502 | } | |
2503 | } | |
2504 | ||
2505 | /* Single-bit compares should always be against zero. */ | |
2506 | if (lbitsize == 1 && ! integer_zerop (rhs)) | |
2507 | { | |
2508 | code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR; | |
2509 | rhs = convert (type, integer_zero_node); | |
2510 | } | |
2511 | ||
2512 | /* Make a new bitfield reference, shift the constant over the | |
2513 | appropriate number of bits and mask it with the computed mask | |
2514 | (in case this was a signed field). If we changed it, make a new one. */ | |
5826cacf | 2515 | lhs = make_bit_field_ref (linner, unsigned_type, nbitsize, nbitpos, 1); |
9db73acb RK |
2516 | if (lvolatilep) |
2517 | { | |
2518 | TREE_SIDE_EFFECTS (lhs) = 1; | |
2519 | TREE_THIS_VOLATILE (lhs) = 1; | |
2520 | } | |
6d716ca8 | 2521 | |
c0b9d4c8 RK |
2522 | rhs = fold (const_binop (BIT_AND_EXPR, |
2523 | const_binop (LSHIFT_EXPR, | |
2524 | convert (unsigned_type, rhs), | |
194c082f | 2525 | size_int (lbitpos), 0), |
91d33e36 | 2526 | mask, 0)); |
6d716ca8 RS |
2527 | |
2528 | return build (code, compare_type, | |
c0b9d4c8 | 2529 | build (BIT_AND_EXPR, unsigned_type, lhs, mask), |
6d716ca8 RS |
2530 | rhs); |
2531 | } | |
2532 | \f | |
b2215d83 | 2533 | /* Subroutine for fold_truthop: decode a field reference. |
6d716ca8 RS |
2534 | |
2535 | If EXP is a comparison reference, we return the innermost reference. | |
2536 | ||
2537 | *PBITSIZE is set to the number of bits in the reference, *PBITPOS is | |
2538 | set to the starting bit number. | |
2539 | ||
2540 | If the innermost field can be completely contained in a mode-sized | |
2541 | unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode. | |
2542 | ||
2543 | *PVOLATILEP is set to 1 if the any expression encountered is volatile; | |
2544 | otherwise it is not changed. | |
2545 | ||
2546 | *PUNSIGNEDP is set to the signedness of the field. | |
2547 | ||
2548 | *PMASK is set to the mask used. This is either contained in a | |
2549 | BIT_AND_EXPR or derived from the width of the field. | |
2550 | ||
38e01259 | 2551 | *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any. |
d4453ee5 | 2552 | |
6d716ca8 RS |
2553 | Return 0 if this is not a component reference or is one that we can't |
2554 | do anything with. */ | |
2555 | ||
2556 | static tree | |
2557 | decode_field_reference (exp, pbitsize, pbitpos, pmode, punsignedp, | |
d4453ee5 | 2558 | pvolatilep, pmask, pand_mask) |
6d716ca8 | 2559 | tree exp; |
770ae6cc | 2560 | HOST_WIDE_INT *pbitsize, *pbitpos; |
6d716ca8 RS |
2561 | enum machine_mode *pmode; |
2562 | int *punsignedp, *pvolatilep; | |
2563 | tree *pmask; | |
d4453ee5 | 2564 | tree *pand_mask; |
6d716ca8 | 2565 | { |
6d9f1f5f RK |
2566 | tree and_mask = 0; |
2567 | tree mask, inner, offset; | |
2568 | tree unsigned_type; | |
770ae6cc | 2569 | unsigned int precision; |
6d716ca8 | 2570 | |
b6cc0a72 | 2571 | /* All the optimizations using this function assume integer fields. |
772ae9f0 RK |
2572 | There are problems with FP fields since the type_for_size call |
2573 | below can fail for, e.g., XFmode. */ | |
2574 | if (! INTEGRAL_TYPE_P (TREE_TYPE (exp))) | |
2575 | return 0; | |
2576 | ||
6d716ca8 RS |
2577 | STRIP_NOPS (exp); |
2578 | ||
2579 | if (TREE_CODE (exp) == BIT_AND_EXPR) | |
2580 | { | |
6d9f1f5f | 2581 | and_mask = TREE_OPERAND (exp, 1); |
6d716ca8 | 2582 | exp = TREE_OPERAND (exp, 0); |
6d9f1f5f RK |
2583 | STRIP_NOPS (exp); STRIP_NOPS (and_mask); |
2584 | if (TREE_CODE (and_mask) != INTEGER_CST) | |
6d716ca8 RS |
2585 | return 0; |
2586 | } | |
2587 | ||
f1e60ec6 | 2588 | inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode, |
a06ef755 | 2589 | punsignedp, pvolatilep); |
02103577 | 2590 | if ((inner == exp && and_mask == 0) |
14a774a9 RK |
2591 | || *pbitsize < 0 || offset != 0 |
2592 | || TREE_CODE (inner) == PLACEHOLDER_EXPR) | |
c05a9b68 | 2593 | return 0; |
b6cc0a72 | 2594 | |
6d9f1f5f | 2595 | /* Compute the mask to access the bitfield. */ |
b0c48229 | 2596 | unsigned_type = (*lang_hooks.types.type_for_size) (*pbitsize, 1); |
6d9f1f5f RK |
2597 | precision = TYPE_PRECISION (unsigned_type); |
2598 | ||
2599 | mask = build_int_2 (~0, ~0); | |
2600 | TREE_TYPE (mask) = unsigned_type; | |
2601 | force_fit_type (mask, 0); | |
2602 | mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0); | |
2603 | mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0); | |
2604 | ||
2605 | /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */ | |
2606 | if (and_mask != 0) | |
2607 | mask = fold (build (BIT_AND_EXPR, unsigned_type, | |
2608 | convert (unsigned_type, and_mask), mask)); | |
6d716ca8 RS |
2609 | |
2610 | *pmask = mask; | |
d4453ee5 | 2611 | *pand_mask = and_mask; |
6d716ca8 RS |
2612 | return inner; |
2613 | } | |
2614 | ||
6dc42e49 | 2615 | /* Return non-zero if MASK represents a mask of SIZE ones in the low-order |
6d716ca8 RS |
2616 | bit positions. */ |
2617 | ||
2618 | static int | |
2619 | all_ones_mask_p (mask, size) | |
2620 | tree mask; | |
2621 | int size; | |
2622 | { | |
2623 | tree type = TREE_TYPE (mask); | |
770ae6cc | 2624 | unsigned int precision = TYPE_PRECISION (type); |
13af526d | 2625 | tree tmask; |
6d716ca8 | 2626 | |
13af526d | 2627 | tmask = build_int_2 (~0, ~0); |
ceef8ce4 | 2628 | TREE_TYPE (tmask) = (*lang_hooks.types.signed_type) (type); |
aa830baf | 2629 | force_fit_type (tmask, 0); |
6d716ca8 | 2630 | return |
b6cc0a72 | 2631 | tree_int_cst_equal (mask, |
02103577 RK |
2632 | const_binop (RSHIFT_EXPR, |
2633 | const_binop (LSHIFT_EXPR, tmask, | |
2634 | size_int (precision - size), | |
2635 | 0), | |
2636 | size_int (precision - size), 0)); | |
6d716ca8 | 2637 | } |
b2215d83 | 2638 | |
1f77b5da RS |
2639 | /* Subroutine for fold: determine if VAL is the INTEGER_CONST that |
2640 | represents the sign bit of EXP's type. If EXP represents a sign | |
2641 | or zero extension, also test VAL against the unextended type. | |
2642 | The return value is the (sub)expression whose sign bit is VAL, | |
2643 | or NULL_TREE otherwise. */ | |
2644 | ||
2645 | static tree | |
2646 | sign_bit_p (exp, val) | |
2647 | tree exp; | |
2648 | tree val; | |
2649 | { | |
2650 | unsigned HOST_WIDE_INT lo; | |
2651 | HOST_WIDE_INT hi; | |
2652 | int width; | |
2653 | tree t; | |
2654 | ||
2655 | /* Tree EXP must have a integral type. */ | |
2656 | t = TREE_TYPE (exp); | |
2657 | if (! INTEGRAL_TYPE_P (t)) | |
2658 | return NULL_TREE; | |
2659 | ||
2660 | /* Tree VAL must be an integer constant. */ | |
2661 | if (TREE_CODE (val) != INTEGER_CST | |
2662 | || TREE_CONSTANT_OVERFLOW (val)) | |
2663 | return NULL_TREE; | |
2664 | ||
2665 | width = TYPE_PRECISION (t); | |
2666 | if (width > HOST_BITS_PER_WIDE_INT) | |
2667 | { | |
2668 | hi = (unsigned HOST_WIDE_INT) 1 << (width - HOST_BITS_PER_WIDE_INT - 1); | |
2669 | lo = 0; | |
2670 | } | |
2671 | else | |
2672 | { | |
2673 | hi = 0; | |
2674 | lo = (unsigned HOST_WIDE_INT) 1 << (width - 1); | |
2675 | } | |
2676 | ||
2677 | if (TREE_INT_CST_HIGH (val) == hi && TREE_INT_CST_LOW (val) == lo) | |
2678 | return exp; | |
2679 | ||
2680 | /* Handle extension from a narrower type. */ | |
2681 | if (TREE_CODE (exp) == NOP_EXPR | |
2682 | && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0))) < width) | |
2683 | return sign_bit_p (TREE_OPERAND (exp, 0), val); | |
2684 | ||
2685 | return NULL_TREE; | |
2686 | } | |
2687 | ||
b2215d83 TW |
2688 | /* Subroutine for fold_truthop: determine if an operand is simple enough |
2689 | to be evaluated unconditionally. */ | |
2690 | ||
b6cc0a72 | 2691 | static int |
b2215d83 TW |
2692 | simple_operand_p (exp) |
2693 | tree exp; | |
2694 | { | |
2695 | /* Strip any conversions that don't change the machine mode. */ | |
2696 | while ((TREE_CODE (exp) == NOP_EXPR | |
2697 | || TREE_CODE (exp) == CONVERT_EXPR) | |
2698 | && (TYPE_MODE (TREE_TYPE (exp)) | |
2699 | == TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))))) | |
2700 | exp = TREE_OPERAND (exp, 0); | |
2701 | ||
2702 | return (TREE_CODE_CLASS (TREE_CODE (exp)) == 'c' | |
2f939d94 | 2703 | || (DECL_P (exp) |
b2215d83 TW |
2704 | && ! TREE_ADDRESSABLE (exp) |
2705 | && ! TREE_THIS_VOLATILE (exp) | |
8227896c TW |
2706 | && ! DECL_NONLOCAL (exp) |
2707 | /* Don't regard global variables as simple. They may be | |
2708 | allocated in ways unknown to the compiler (shared memory, | |
2709 | #pragma weak, etc). */ | |
2710 | && ! TREE_PUBLIC (exp) | |
2711 | && ! DECL_EXTERNAL (exp) | |
2712 | /* Loading a static variable is unduly expensive, but global | |
2713 | registers aren't expensive. */ | |
2714 | && (! TREE_STATIC (exp) || DECL_REGISTER (exp)))); | |
b2215d83 | 2715 | } |
6d716ca8 | 2716 | \f |
ebde8a27 RK |
2717 | /* The following functions are subroutines to fold_range_test and allow it to |
2718 | try to change a logical combination of comparisons into a range test. | |
2719 | ||
2720 | For example, both | |
f42ef510 | 2721 | X == 2 || X == 3 || X == 4 || X == 5 |
ebde8a27 RK |
2722 | and |
2723 | X >= 2 && X <= 5 | |
2724 | are converted to | |
2725 | (unsigned) (X - 2) <= 3 | |
2726 | ||
956d6950 | 2727 | We describe each set of comparisons as being either inside or outside |
ebde8a27 RK |
2728 | a range, using a variable named like IN_P, and then describe the |
2729 | range with a lower and upper bound. If one of the bounds is omitted, | |
2730 | it represents either the highest or lowest value of the type. | |
2731 | ||
2732 | In the comments below, we represent a range by two numbers in brackets | |
956d6950 | 2733 | preceded by a "+" to designate being inside that range, or a "-" to |
ebde8a27 RK |
2734 | designate being outside that range, so the condition can be inverted by |
2735 | flipping the prefix. An omitted bound is represented by a "-". For | |
2736 | example, "- [-, 10]" means being outside the range starting at the lowest | |
2737 | possible value and ending at 10, in other words, being greater than 10. | |
2738 | The range "+ [-, -]" is always true and hence the range "- [-, -]" is | |
2739 | always false. | |
2740 | ||
2741 | We set up things so that the missing bounds are handled in a consistent | |
2742 | manner so neither a missing bound nor "true" and "false" need to be | |
2743 | handled using a special case. */ | |
2744 | ||
2745 | /* Return the result of applying CODE to ARG0 and ARG1, but handle the case | |
2746 | of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P | |
2747 | and UPPER1_P are nonzero if the respective argument is an upper bound | |
2748 | and zero for a lower. TYPE, if nonzero, is the type of the result; it | |
2749 | must be specified for a comparison. ARG1 will be converted to ARG0's | |
2750 | type if both are specified. */ | |
ef659ec0 | 2751 | |
ebde8a27 RK |
2752 | static tree |
2753 | range_binop (code, type, arg0, upper0_p, arg1, upper1_p) | |
2754 | enum tree_code code; | |
2755 | tree type; | |
2756 | tree arg0, arg1; | |
2757 | int upper0_p, upper1_p; | |
2758 | { | |
27bae8e5 | 2759 | tree tem; |
ebde8a27 RK |
2760 | int result; |
2761 | int sgn0, sgn1; | |
ef659ec0 | 2762 | |
ebde8a27 RK |
2763 | /* If neither arg represents infinity, do the normal operation. |
2764 | Else, if not a comparison, return infinity. Else handle the special | |
2765 | comparison rules. Note that most of the cases below won't occur, but | |
2766 | are handled for consistency. */ | |
ef659ec0 | 2767 | |
ebde8a27 | 2768 | if (arg0 != 0 && arg1 != 0) |
27bae8e5 RK |
2769 | { |
2770 | tem = fold (build (code, type != 0 ? type : TREE_TYPE (arg0), | |
2771 | arg0, convert (TREE_TYPE (arg0), arg1))); | |
2772 | STRIP_NOPS (tem); | |
2773 | return TREE_CODE (tem) == INTEGER_CST ? tem : 0; | |
2774 | } | |
ef659ec0 | 2775 | |
ebde8a27 RK |
2776 | if (TREE_CODE_CLASS (code) != '<') |
2777 | return 0; | |
2778 | ||
2779 | /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0 | |
d7b3ea38 NS |
2780 | for neither. In real maths, we cannot assume open ended ranges are |
2781 | the same. But, this is computer arithmetic, where numbers are finite. | |
2782 | We can therefore make the transformation of any unbounded range with | |
2783 | the value Z, Z being greater than any representable number. This permits | |
30f7a378 | 2784 | us to treat unbounded ranges as equal. */ |
ebde8a27 | 2785 | sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1); |
4e644c93 | 2786 | sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1); |
ebde8a27 RK |
2787 | switch (code) |
2788 | { | |
d7b3ea38 NS |
2789 | case EQ_EXPR: |
2790 | result = sgn0 == sgn1; | |
2791 | break; | |
2792 | case NE_EXPR: | |
2793 | result = sgn0 != sgn1; | |
ebde8a27 | 2794 | break; |
d7b3ea38 | 2795 | case LT_EXPR: |
ebde8a27 RK |
2796 | result = sgn0 < sgn1; |
2797 | break; | |
d7b3ea38 NS |
2798 | case LE_EXPR: |
2799 | result = sgn0 <= sgn1; | |
2800 | break; | |
2801 | case GT_EXPR: | |
ebde8a27 RK |
2802 | result = sgn0 > sgn1; |
2803 | break; | |
d7b3ea38 NS |
2804 | case GE_EXPR: |
2805 | result = sgn0 >= sgn1; | |
2806 | break; | |
e9a25f70 JL |
2807 | default: |
2808 | abort (); | |
ebde8a27 RK |
2809 | } |
2810 | ||
2811 | return convert (type, result ? integer_one_node : integer_zero_node); | |
2812 | } | |
b6cc0a72 | 2813 | \f |
ebde8a27 RK |
2814 | /* Given EXP, a logical expression, set the range it is testing into |
2815 | variables denoted by PIN_P, PLOW, and PHIGH. Return the expression | |
f42ef510 | 2816 | actually being tested. *PLOW and *PHIGH will be made of the same type |
ebde8a27 RK |
2817 | as the returned expression. If EXP is not a comparison, we will most |
2818 | likely not be returning a useful value and range. */ | |
ef659ec0 | 2819 | |
6dc7571d | 2820 | static tree |
ebde8a27 RK |
2821 | make_range (exp, pin_p, plow, phigh) |
2822 | tree exp; | |
2823 | int *pin_p; | |
2824 | tree *plow, *phigh; | |
ef659ec0 | 2825 | { |
ebde8a27 | 2826 | enum tree_code code; |
07444f1d | 2827 | tree arg0 = NULL_TREE, arg1 = NULL_TREE, type = NULL_TREE; |
7d12cee1 | 2828 | tree orig_type = NULL_TREE; |
ebde8a27 RK |
2829 | int in_p, n_in_p; |
2830 | tree low, high, n_low, n_high; | |
ef659ec0 | 2831 | |
ebde8a27 RK |
2832 | /* Start with simply saying "EXP != 0" and then look at the code of EXP |
2833 | and see if we can refine the range. Some of the cases below may not | |
2834 | happen, but it doesn't seem worth worrying about this. We "continue" | |
2835 | the outer loop when we've changed something; otherwise we "break" | |
2836 | the switch, which will "break" the while. */ | |
ef659ec0 | 2837 | |
ebde8a27 RK |
2838 | in_p = 0, low = high = convert (TREE_TYPE (exp), integer_zero_node); |
2839 | ||
2840 | while (1) | |
ef659ec0 | 2841 | { |
ebde8a27 | 2842 | code = TREE_CODE (exp); |
30d68b86 MM |
2843 | |
2844 | if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code))) | |
2845 | { | |
2846 | arg0 = TREE_OPERAND (exp, 0); | |
b6cc0a72 | 2847 | if (TREE_CODE_CLASS (code) == '<' |
30d68b86 MM |
2848 | || TREE_CODE_CLASS (code) == '1' |
2849 | || TREE_CODE_CLASS (code) == '2') | |
2850 | type = TREE_TYPE (arg0); | |
b6cc0a72 | 2851 | if (TREE_CODE_CLASS (code) == '2' |
30d68b86 | 2852 | || TREE_CODE_CLASS (code) == '<' |
b6cc0a72 | 2853 | || (TREE_CODE_CLASS (code) == 'e' |
efd58783 | 2854 | && TREE_CODE_LENGTH (code) > 1)) |
30d68b86 MM |
2855 | arg1 = TREE_OPERAND (exp, 1); |
2856 | } | |
ef659ec0 | 2857 | |
cc33944a RE |
2858 | /* Set ORIG_TYPE as soon as TYPE is non-null so that we do not |
2859 | lose a cast by accident. */ | |
2860 | if (type != NULL_TREE && orig_type == NULL_TREE) | |
2861 | orig_type = type; | |
2862 | ||
ebde8a27 RK |
2863 | switch (code) |
2864 | { | |
2865 | case TRUTH_NOT_EXPR: | |
2866 | in_p = ! in_p, exp = arg0; | |
2867 | continue; | |
2868 | ||
2869 | case EQ_EXPR: case NE_EXPR: | |
2870 | case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR: | |
2871 | /* We can only do something if the range is testing for zero | |
2872 | and if the second operand is an integer constant. Note that | |
2873 | saying something is "in" the range we make is done by | |
2874 | complementing IN_P since it will set in the initial case of | |
2875 | being not equal to zero; "out" is leaving it alone. */ | |
2876 | if (low == 0 || high == 0 | |
2877 | || ! integer_zerop (low) || ! integer_zerop (high) | |
2878 | || TREE_CODE (arg1) != INTEGER_CST) | |
2879 | break; | |
ef659ec0 | 2880 | |
ebde8a27 RK |
2881 | switch (code) |
2882 | { | |
2883 | case NE_EXPR: /* - [c, c] */ | |
2884 | low = high = arg1; | |
2885 | break; | |
2886 | case EQ_EXPR: /* + [c, c] */ | |
2887 | in_p = ! in_p, low = high = arg1; | |
2888 | break; | |
2889 | case GT_EXPR: /* - [-, c] */ | |
2890 | low = 0, high = arg1; | |
2891 | break; | |
2892 | case GE_EXPR: /* + [c, -] */ | |
2893 | in_p = ! in_p, low = arg1, high = 0; | |
2894 | break; | |
2895 | case LT_EXPR: /* - [c, -] */ | |
2896 | low = arg1, high = 0; | |
2897 | break; | |
2898 | case LE_EXPR: /* + [-, c] */ | |
2899 | in_p = ! in_p, low = 0, high = arg1; | |
2900 | break; | |
e9a25f70 JL |
2901 | default: |
2902 | abort (); | |
ebde8a27 | 2903 | } |
ef659ec0 | 2904 | |
ebde8a27 | 2905 | exp = arg0; |
ef659ec0 | 2906 | |
7f423031 | 2907 | /* If this is an unsigned comparison, we also know that EXP is |
0e1c7fc7 RK |
2908 | greater than or equal to zero. We base the range tests we make |
2909 | on that fact, so we record it here so we can parse existing | |
2910 | range tests. */ | |
7f423031 | 2911 | if (TREE_UNSIGNED (type) && (low == 0 || high == 0)) |
ebde8a27 RK |
2912 | { |
2913 | if (! merge_ranges (&n_in_p, &n_low, &n_high, in_p, low, high, | |
2914 | 1, convert (type, integer_zero_node), | |
0e1c7fc7 | 2915 | NULL_TREE)) |
ebde8a27 | 2916 | break; |
ef659ec0 | 2917 | |
ebde8a27 | 2918 | in_p = n_in_p, low = n_low, high = n_high; |
0e1c7fc7 | 2919 | |
c565a6b7 R |
2920 | /* If the high bound is missing, but we |
2921 | have a low bound, reverse the range so | |
2922 | it goes from zero to the low bound minus 1. */ | |
2923 | if (high == 0 && low) | |
0e1c7fc7 RK |
2924 | { |
2925 | in_p = ! in_p; | |
2926 | high = range_binop (MINUS_EXPR, NULL_TREE, low, 0, | |
2927 | integer_one_node, 0); | |
2928 | low = convert (type, integer_zero_node); | |
2929 | } | |
ebde8a27 RK |
2930 | } |
2931 | continue; | |
2932 | ||
2933 | case NEGATE_EXPR: | |
2934 | /* (-x) IN [a,b] -> x in [-b, -a] */ | |
2935 | n_low = range_binop (MINUS_EXPR, type, | |
2936 | convert (type, integer_zero_node), 0, high, 1); | |
2937 | n_high = range_binop (MINUS_EXPR, type, | |
2938 | convert (type, integer_zero_node), 0, low, 0); | |
2939 | low = n_low, high = n_high; | |
2940 | exp = arg0; | |
2941 | continue; | |
2942 | ||
2943 | case BIT_NOT_EXPR: | |
2944 | /* ~ X -> -X - 1 */ | |
1baa375f | 2945 | exp = build (MINUS_EXPR, type, negate_expr (arg0), |
27bae8e5 | 2946 | convert (type, integer_one_node)); |
ebde8a27 RK |
2947 | continue; |
2948 | ||
2949 | case PLUS_EXPR: case MINUS_EXPR: | |
2950 | if (TREE_CODE (arg1) != INTEGER_CST) | |
2951 | break; | |
2952 | ||
2953 | /* If EXP is signed, any overflow in the computation is undefined, | |
2954 | so we don't worry about it so long as our computations on | |
2955 | the bounds don't overflow. For unsigned, overflow is defined | |
2956 | and this is exactly the right thing. */ | |
2957 | n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR, | |
2958 | type, low, 0, arg1, 0); | |
2959 | n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR, | |
2960 | type, high, 1, arg1, 0); | |
2961 | if ((n_low != 0 && TREE_OVERFLOW (n_low)) | |
2962 | || (n_high != 0 && TREE_OVERFLOW (n_high))) | |
2963 | break; | |
2964 | ||
3c00684e JL |
2965 | /* Check for an unsigned range which has wrapped around the maximum |
2966 | value thus making n_high < n_low, and normalize it. */ | |
5a9d82a6 | 2967 | if (n_low && n_high && tree_int_cst_lt (n_high, n_low)) |
3c00684e JL |
2968 | { |
2969 | low = range_binop (PLUS_EXPR, type, n_high, 0, | |
0e1c7fc7 | 2970 | integer_one_node, 0); |
3c00684e | 2971 | high = range_binop (MINUS_EXPR, type, n_low, 0, |
c2b63960 AO |
2972 | integer_one_node, 0); |
2973 | ||
2974 | /* If the range is of the form +/- [ x+1, x ], we won't | |
2975 | be able to normalize it. But then, it represents the | |
2976 | whole range or the empty set, so make it | |
2977 | +/- [ -, - ]. */ | |
2978 | if (tree_int_cst_equal (n_low, low) | |
2979 | && tree_int_cst_equal (n_high, high)) | |
2980 | low = high = 0; | |
2981 | else | |
2982 | in_p = ! in_p; | |
3c00684e | 2983 | } |
5a9d82a6 JW |
2984 | else |
2985 | low = n_low, high = n_high; | |
27bae8e5 | 2986 | |
ebde8a27 RK |
2987 | exp = arg0; |
2988 | continue; | |
2989 | ||
2990 | case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR: | |
7d12cee1 JL |
2991 | if (TYPE_PRECISION (type) > TYPE_PRECISION (orig_type)) |
2992 | break; | |
2993 | ||
ebde8a27 RK |
2994 | if (! INTEGRAL_TYPE_P (type) |
2995 | || (low != 0 && ! int_fits_type_p (low, type)) | |
2996 | || (high != 0 && ! int_fits_type_p (high, type))) | |
2997 | break; | |
2998 | ||
ce2157a1 | 2999 | n_low = low, n_high = high; |
ebde8a27 | 3000 | |
ce2157a1 JL |
3001 | if (n_low != 0) |
3002 | n_low = convert (type, n_low); | |
3003 | ||
3004 | if (n_high != 0) | |
3005 | n_high = convert (type, n_high); | |
3006 | ||
3007 | /* If we're converting from an unsigned to a signed type, | |
3008 | we will be doing the comparison as unsigned. The tests above | |
3009 | have already verified that LOW and HIGH are both positive. | |
3010 | ||
3011 | So we have to make sure that the original unsigned value will | |
3012 | be interpreted as positive. */ | |
3013 | if (TREE_UNSIGNED (type) && ! TREE_UNSIGNED (TREE_TYPE (exp))) | |
3014 | { | |
b0c48229 NB |
3015 | tree equiv_type = (*lang_hooks.types.type_for_mode) |
3016 | (TYPE_MODE (type), 1); | |
e1ee5cdc RH |
3017 | tree high_positive; |
3018 | ||
3019 | /* A range without an upper bound is, naturally, unbounded. | |
3020 | Since convert would have cropped a very large value, use | |
14a774a9 RK |
3021 | the max value for the destination type. */ |
3022 | high_positive | |
3023 | = TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type) | |
3024 | : TYPE_MAX_VALUE (type); | |
e1ee5cdc | 3025 | |
e1ee5cdc RH |
3026 | high_positive = fold (build (RSHIFT_EXPR, type, |
3027 | convert (type, high_positive), | |
3028 | convert (type, integer_one_node))); | |
b6cc0a72 | 3029 | |
ce2157a1 JL |
3030 | /* If the low bound is specified, "and" the range with the |
3031 | range for which the original unsigned value will be | |
3032 | positive. */ | |
3033 | if (low != 0) | |
3034 | { | |
3035 | if (! merge_ranges (&n_in_p, &n_low, &n_high, | |
3036 | 1, n_low, n_high, | |
3037 | 1, convert (type, integer_zero_node), | |
3038 | high_positive)) | |
3039 | break; | |
3040 | ||
3041 | in_p = (n_in_p == in_p); | |
3042 | } | |
3043 | else | |
3044 | { | |
3045 | /* Otherwise, "or" the range with the range of the input | |
3046 | that will be interpreted as negative. */ | |
3047 | if (! merge_ranges (&n_in_p, &n_low, &n_high, | |
3048 | 0, n_low, n_high, | |
3049 | 1, convert (type, integer_zero_node), | |
3050 | high_positive)) | |
3051 | break; | |
3052 | ||
3053 | in_p = (in_p != n_in_p); | |
3054 | } | |
3055 | } | |
ebde8a27 RK |
3056 | |
3057 | exp = arg0; | |
ce2157a1 | 3058 | low = n_low, high = n_high; |
ebde8a27 | 3059 | continue; |
ce2157a1 JL |
3060 | |
3061 | default: | |
3062 | break; | |
ef659ec0 | 3063 | } |
ebde8a27 RK |
3064 | |
3065 | break; | |
ef659ec0 | 3066 | } |
ebde8a27 | 3067 | |
80906567 RK |
3068 | /* If EXP is a constant, we can evaluate whether this is true or false. */ |
3069 | if (TREE_CODE (exp) == INTEGER_CST) | |
3070 | { | |
3071 | in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node, | |
3072 | exp, 0, low, 0)) | |
3073 | && integer_onep (range_binop (LE_EXPR, integer_type_node, | |
3074 | exp, 1, high, 1))); | |
3075 | low = high = 0; | |
3076 | exp = 0; | |
3077 | } | |
3078 | ||
ebde8a27 RK |
3079 | *pin_p = in_p, *plow = low, *phigh = high; |
3080 | return exp; | |
3081 | } | |
3082 | \f | |
3083 | /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result | |
3084 | type, TYPE, return an expression to test if EXP is in (or out of, depending | |
3085 | on IN_P) the range. */ | |
3086 | ||
3087 | static tree | |
3088 | build_range_check (type, exp, in_p, low, high) | |
3089 | tree type; | |
3090 | tree exp; | |
3091 | int in_p; | |
3092 | tree low, high; | |
3093 | { | |
3094 | tree etype = TREE_TYPE (exp); | |
dbfb1116 | 3095 | tree value; |
ebde8a27 RK |
3096 | |
3097 | if (! in_p | |
3098 | && (0 != (value = build_range_check (type, exp, 1, low, high)))) | |
3099 | return invert_truthvalue (value); | |
3100 | ||
dbfb1116 | 3101 | if (low == 0 && high == 0) |
ebde8a27 RK |
3102 | return convert (type, integer_one_node); |
3103 | ||
dbfb1116 | 3104 | if (low == 0) |
ebde8a27 RK |
3105 | return fold (build (LE_EXPR, type, exp, high)); |
3106 | ||
dbfb1116 | 3107 | if (high == 0) |
ebde8a27 RK |
3108 | return fold (build (GE_EXPR, type, exp, low)); |
3109 | ||
dbfb1116 | 3110 | if (operand_equal_p (low, high, 0)) |
ebde8a27 RK |
3111 | return fold (build (EQ_EXPR, type, exp, low)); |
3112 | ||
dbfb1116 | 3113 | if (integer_zerop (low)) |
ef659ec0 | 3114 | { |
dbfb1116 | 3115 | if (! TREE_UNSIGNED (etype)) |
dd3f0101 KH |
3116 | { |
3117 | etype = (*lang_hooks.types.unsigned_type) (etype); | |
3118 | high = convert (etype, high); | |
3119 | exp = convert (etype, exp); | |
3120 | } | |
dbfb1116 | 3121 | return build_range_check (type, exp, 1, 0, high); |
ebde8a27 | 3122 | } |
ef659ec0 | 3123 | |
dbfb1116 RS |
3124 | /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */ |
3125 | if (integer_onep (low) && TREE_CODE (high) == INTEGER_CST) | |
3126 | { | |
3127 | unsigned HOST_WIDE_INT lo; | |
3128 | HOST_WIDE_INT hi; | |
3129 | int prec; | |
3130 | ||
3131 | prec = TYPE_PRECISION (etype); | |
3132 | if (prec <= HOST_BITS_PER_WIDE_INT) | |
dd3f0101 KH |
3133 | { |
3134 | hi = 0; | |
3135 | lo = ((unsigned HOST_WIDE_INT) 1 << (prec - 1)) - 1; | |
3136 | } | |
dbfb1116 | 3137 | else |
dd3f0101 KH |
3138 | { |
3139 | hi = ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1)) - 1; | |
3140 | lo = (unsigned HOST_WIDE_INT) -1; | |
3141 | } | |
dbfb1116 RS |
3142 | |
3143 | if (TREE_INT_CST_HIGH (high) == hi && TREE_INT_CST_LOW (high) == lo) | |
dd3f0101 KH |
3144 | { |
3145 | if (TREE_UNSIGNED (etype)) | |
3146 | { | |
3147 | etype = (*lang_hooks.types.signed_type) (etype); | |
3148 | exp = convert (etype, exp); | |
3149 | } | |
3150 | return fold (build (GT_EXPR, type, exp, | |
3151 | convert (etype, integer_zero_node))); | |
3152 | } | |
dbfb1116 RS |
3153 | } |
3154 | ||
3155 | if (0 != (value = const_binop (MINUS_EXPR, high, low, 0)) | |
3156 | && ! TREE_OVERFLOW (value)) | |
ebde8a27 RK |
3157 | return build_range_check (type, |
3158 | fold (build (MINUS_EXPR, etype, exp, low)), | |
3159 | 1, convert (etype, integer_zero_node), value); | |
dbfb1116 RS |
3160 | |
3161 | return 0; | |
ebde8a27 RK |
3162 | } |
3163 | \f | |
b6cc0a72 | 3164 | /* Given two ranges, see if we can merge them into one. Return 1 if we |
ebde8a27 | 3165 | can, 0 if we can't. Set the output range into the specified parameters. */ |
ef659ec0 | 3166 | |
ebde8a27 RK |
3167 | static int |
3168 | merge_ranges (pin_p, plow, phigh, in0_p, low0, high0, in1_p, low1, high1) | |
3169 | int *pin_p; | |
3170 | tree *plow, *phigh; | |
3171 | int in0_p, in1_p; | |
3172 | tree low0, high0, low1, high1; | |
3173 | { | |
3174 | int no_overlap; | |
3175 | int subset; | |
3176 | int temp; | |
3177 | tree tem; | |
3178 | int in_p; | |
3179 | tree low, high; | |
ce2157a1 JL |
3180 | int lowequal = ((low0 == 0 && low1 == 0) |
3181 | || integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3182 | low0, 0, low1, 0))); | |
3183 | int highequal = ((high0 == 0 && high1 == 0) | |
3184 | || integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3185 | high0, 1, high1, 1))); | |
3186 | ||
3187 | /* Make range 0 be the range that starts first, or ends last if they | |
3188 | start at the same value. Swap them if it isn't. */ | |
b6cc0a72 | 3189 | if (integer_onep (range_binop (GT_EXPR, integer_type_node, |
ebde8a27 | 3190 | low0, 0, low1, 0)) |
ce2157a1 | 3191 | || (lowequal |
ebde8a27 | 3192 | && integer_onep (range_binop (GT_EXPR, integer_type_node, |
ce2157a1 | 3193 | high1, 1, high0, 1)))) |
ebde8a27 RK |
3194 | { |
3195 | temp = in0_p, in0_p = in1_p, in1_p = temp; | |
3196 | tem = low0, low0 = low1, low1 = tem; | |
3197 | tem = high0, high0 = high1, high1 = tem; | |
3198 | } | |
ef659ec0 | 3199 | |
ebde8a27 RK |
3200 | /* Now flag two cases, whether the ranges are disjoint or whether the |
3201 | second range is totally subsumed in the first. Note that the tests | |
3202 | below are simplified by the ones above. */ | |
3203 | no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node, | |
3204 | high0, 1, low1, 0)); | |
5df8a1f2 | 3205 | subset = integer_onep (range_binop (LE_EXPR, integer_type_node, |
ebde8a27 RK |
3206 | high1, 1, high0, 1)); |
3207 | ||
3208 | /* We now have four cases, depending on whether we are including or | |
3209 | excluding the two ranges. */ | |
3210 | if (in0_p && in1_p) | |
3211 | { | |
3212 | /* If they don't overlap, the result is false. If the second range | |
3213 | is a subset it is the result. Otherwise, the range is from the start | |
3214 | of the second to the end of the first. */ | |
3215 | if (no_overlap) | |
3216 | in_p = 0, low = high = 0; | |
3217 | else if (subset) | |
3218 | in_p = 1, low = low1, high = high1; | |
3219 | else | |
3220 | in_p = 1, low = low1, high = high0; | |
3221 | } | |
ef659ec0 | 3222 | |
ebde8a27 RK |
3223 | else if (in0_p && ! in1_p) |
3224 | { | |
ce2157a1 JL |
3225 | /* If they don't overlap, the result is the first range. If they are |
3226 | equal, the result is false. If the second range is a subset of the | |
3227 | first, and the ranges begin at the same place, we go from just after | |
3228 | the end of the first range to the end of the second. If the second | |
3229 | range is not a subset of the first, or if it is a subset and both | |
3230 | ranges end at the same place, the range starts at the start of the | |
3231 | first range and ends just before the second range. | |
3232 | Otherwise, we can't describe this as a single range. */ | |
ebde8a27 RK |
3233 | if (no_overlap) |
3234 | in_p = 1, low = low0, high = high0; | |
ce2157a1 | 3235 | else if (lowequal && highequal) |
405862dd | 3236 | in_p = 0, low = high = 0; |
ce2157a1 JL |
3237 | else if (subset && lowequal) |
3238 | { | |
3239 | in_p = 1, high = high0; | |
3240 | low = range_binop (PLUS_EXPR, NULL_TREE, high1, 0, | |
b6cc0a72 | 3241 | integer_one_node, 0); |
ce2157a1 JL |
3242 | } |
3243 | else if (! subset || highequal) | |
ebde8a27 RK |
3244 | { |
3245 | in_p = 1, low = low0; | |
3246 | high = range_binop (MINUS_EXPR, NULL_TREE, low1, 0, | |
0e1c7fc7 | 3247 | integer_one_node, 0); |
ebde8a27 | 3248 | } |
ce2157a1 JL |
3249 | else |
3250 | return 0; | |
ebde8a27 | 3251 | } |
ef659ec0 | 3252 | |
ebde8a27 RK |
3253 | else if (! in0_p && in1_p) |
3254 | { | |
3255 | /* If they don't overlap, the result is the second range. If the second | |
3256 | is a subset of the first, the result is false. Otherwise, | |
3257 | the range starts just after the first range and ends at the | |
3258 | end of the second. */ | |
3259 | if (no_overlap) | |
3260 | in_p = 1, low = low1, high = high1; | |
14a774a9 | 3261 | else if (subset || highequal) |
ebde8a27 RK |
3262 | in_p = 0, low = high = 0; |
3263 | else | |
3264 | { | |
3265 | in_p = 1, high = high1; | |
3266 | low = range_binop (PLUS_EXPR, NULL_TREE, high0, 1, | |
3267 | integer_one_node, 0); | |
ef659ec0 TW |
3268 | } |
3269 | } | |
3270 | ||
ebde8a27 RK |
3271 | else |
3272 | { | |
3273 | /* The case where we are excluding both ranges. Here the complex case | |
3274 | is if they don't overlap. In that case, the only time we have a | |
3275 | range is if they are adjacent. If the second is a subset of the | |
3276 | first, the result is the first. Otherwise, the range to exclude | |
3277 | starts at the beginning of the first range and ends at the end of the | |
3278 | second. */ | |
3279 | if (no_overlap) | |
3280 | { | |
3281 | if (integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3282 | range_binop (PLUS_EXPR, NULL_TREE, | |
3283 | high0, 1, | |
3284 | integer_one_node, 1), | |
3285 | 1, low1, 0))) | |
3286 | in_p = 0, low = low0, high = high1; | |
3287 | else | |
3288 | return 0; | |
3289 | } | |
3290 | else if (subset) | |
3291 | in_p = 0, low = low0, high = high0; | |
3292 | else | |
3293 | in_p = 0, low = low0, high = high1; | |
3294 | } | |
f5902869 | 3295 | |
ebde8a27 RK |
3296 | *pin_p = in_p, *plow = low, *phigh = high; |
3297 | return 1; | |
3298 | } | |
3299 | \f | |
3300 | /* EXP is some logical combination of boolean tests. See if we can | |
3301 | merge it into some range test. Return the new tree if so. */ | |
ef659ec0 | 3302 | |
ebde8a27 RK |
3303 | static tree |
3304 | fold_range_test (exp) | |
3305 | tree exp; | |
3306 | { | |
3307 | int or_op = (TREE_CODE (exp) == TRUTH_ORIF_EXPR | |
3308 | || TREE_CODE (exp) == TRUTH_OR_EXPR); | |
3309 | int in0_p, in1_p, in_p; | |
3310 | tree low0, low1, low, high0, high1, high; | |
3311 | tree lhs = make_range (TREE_OPERAND (exp, 0), &in0_p, &low0, &high0); | |
3312 | tree rhs = make_range (TREE_OPERAND (exp, 1), &in1_p, &low1, &high1); | |
3313 | tree tem; | |
ef659ec0 | 3314 | |
ebde8a27 RK |
3315 | /* If this is an OR operation, invert both sides; we will invert |
3316 | again at the end. */ | |
3317 | if (or_op) | |
3318 | in0_p = ! in0_p, in1_p = ! in1_p; | |
3319 | ||
3320 | /* If both expressions are the same, if we can merge the ranges, and we | |
80906567 RK |
3321 | can build the range test, return it or it inverted. If one of the |
3322 | ranges is always true or always false, consider it to be the same | |
3323 | expression as the other. */ | |
3324 | if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0)) | |
ebde8a27 RK |
3325 | && merge_ranges (&in_p, &low, &high, in0_p, low0, high0, |
3326 | in1_p, low1, high1) | |
80906567 RK |
3327 | && 0 != (tem = (build_range_check (TREE_TYPE (exp), |
3328 | lhs != 0 ? lhs | |
3329 | : rhs != 0 ? rhs : integer_zero_node, | |
ebde8a27 RK |
3330 | in_p, low, high)))) |
3331 | return or_op ? invert_truthvalue (tem) : tem; | |
3332 | ||
3333 | /* On machines where the branch cost is expensive, if this is a | |
3334 | short-circuited branch and the underlying object on both sides | |
3335 | is the same, make a non-short-circuit operation. */ | |
3336 | else if (BRANCH_COST >= 2 | |
7cf5c9e1 | 3337 | && lhs != 0 && rhs != 0 |
ebde8a27 RK |
3338 | && (TREE_CODE (exp) == TRUTH_ANDIF_EXPR |
3339 | || TREE_CODE (exp) == TRUTH_ORIF_EXPR) | |
3340 | && operand_equal_p (lhs, rhs, 0)) | |
ef659ec0 | 3341 | { |
f0eebf28 | 3342 | /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR |
9ec36da5 JL |
3343 | unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in |
3344 | which cases we can't do this. */ | |
ebde8a27 RK |
3345 | if (simple_operand_p (lhs)) |
3346 | return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3347 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR, | |
3348 | TREE_TYPE (exp), TREE_OPERAND (exp, 0), | |
3349 | TREE_OPERAND (exp, 1)); | |
f0eebf28 | 3350 | |
43577e6b | 3351 | else if ((*lang_hooks.decls.global_bindings_p) () == 0 |
9ec36da5 | 3352 | && ! contains_placeholder_p (lhs)) |
ebde8a27 RK |
3353 | { |
3354 | tree common = save_expr (lhs); | |
3355 | ||
3356 | if (0 != (lhs = build_range_check (TREE_TYPE (exp), common, | |
3357 | or_op ? ! in0_p : in0_p, | |
3358 | low0, high0)) | |
3359 | && (0 != (rhs = build_range_check (TREE_TYPE (exp), common, | |
3360 | or_op ? ! in1_p : in1_p, | |
3361 | low1, high1)))) | |
3362 | return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3363 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR, | |
3364 | TREE_TYPE (exp), lhs, rhs); | |
3365 | } | |
ef659ec0 | 3366 | } |
de153e82 | 3367 | |
de153e82 | 3368 | return 0; |
ef659ec0 TW |
3369 | } |
3370 | \f | |
02103577 | 3371 | /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P |
25216284 | 3372 | bit value. Arrange things so the extra bits will be set to zero if and |
d4453ee5 RK |
3373 | only if C is signed-extended to its full width. If MASK is nonzero, |
3374 | it is an INTEGER_CST that should be AND'ed with the extra bits. */ | |
02103577 RK |
3375 | |
3376 | static tree | |
d4453ee5 | 3377 | unextend (c, p, unsignedp, mask) |
02103577 RK |
3378 | tree c; |
3379 | int p; | |
3380 | int unsignedp; | |
d4453ee5 | 3381 | tree mask; |
02103577 RK |
3382 | { |
3383 | tree type = TREE_TYPE (c); | |
3384 | int modesize = GET_MODE_BITSIZE (TYPE_MODE (type)); | |
3385 | tree temp; | |
3386 | ||
3387 | if (p == modesize || unsignedp) | |
3388 | return c; | |
3389 | ||
02103577 | 3390 | /* We work by getting just the sign bit into the low-order bit, then |
9faa82d8 | 3391 | into the high-order bit, then sign-extend. We then XOR that value |
02103577 RK |
3392 | with C. */ |
3393 | temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1), 0); | |
3394 | temp = const_binop (BIT_AND_EXPR, temp, size_int (1), 0); | |
cf85c69b JW |
3395 | |
3396 | /* We must use a signed type in order to get an arithmetic right shift. | |
3397 | However, we must also avoid introducing accidental overflows, so that | |
b6cc0a72 | 3398 | a subsequent call to integer_zerop will work. Hence we must |
cf85c69b JW |
3399 | do the type conversion here. At this point, the constant is either |
3400 | zero or one, and the conversion to a signed type can never overflow. | |
3401 | We could get an overflow if this conversion is done anywhere else. */ | |
3402 | if (TREE_UNSIGNED (type)) | |
ceef8ce4 | 3403 | temp = convert ((*lang_hooks.types.signed_type) (type), temp); |
cf85c69b | 3404 | |
02103577 RK |
3405 | temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0); |
3406 | temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0); | |
d4453ee5 RK |
3407 | if (mask != 0) |
3408 | temp = const_binop (BIT_AND_EXPR, temp, convert (TREE_TYPE (c), mask), 0); | |
cf85c69b JW |
3409 | /* If necessary, convert the type back to match the type of C. */ |
3410 | if (TREE_UNSIGNED (type)) | |
3411 | temp = convert (type, temp); | |
d4453ee5 | 3412 | |
02103577 RK |
3413 | return convert (type, const_binop (BIT_XOR_EXPR, c, temp, 0)); |
3414 | } | |
3415 | \f | |
b2215d83 TW |
3416 | /* Find ways of folding logical expressions of LHS and RHS: |
3417 | Try to merge two comparisons to the same innermost item. | |
3418 | Look for range tests like "ch >= '0' && ch <= '9'". | |
3419 | Look for combinations of simple terms on machines with expensive branches | |
3420 | and evaluate the RHS unconditionally. | |
6d716ca8 RS |
3421 | |
3422 | For example, if we have p->a == 2 && p->b == 4 and we can make an | |
3423 | object large enough to span both A and B, we can do this with a comparison | |
3424 | against the object ANDed with the a mask. | |
3425 | ||
3426 | If we have p->a == q->a && p->b == q->b, we may be able to use bit masking | |
3427 | operations to do this with one comparison. | |
3428 | ||
3429 | We check for both normal comparisons and the BIT_AND_EXPRs made this by | |
3430 | function and the one above. | |
3431 | ||
3432 | CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR, | |
3433 | TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR. | |
3434 | ||
3435 | TRUTH_TYPE is the type of the logical operand and LHS and RHS are its | |
3436 | two operands. | |
3437 | ||
3438 | We return the simplified tree or 0 if no optimization is possible. */ | |
3439 | ||
3440 | static tree | |
b2215d83 | 3441 | fold_truthop (code, truth_type, lhs, rhs) |
6d716ca8 RS |
3442 | enum tree_code code; |
3443 | tree truth_type, lhs, rhs; | |
3444 | { | |
f42ef510 | 3445 | /* If this is the "or" of two comparisons, we can do something if |
6d716ca8 | 3446 | the comparisons are NE_EXPR. If this is the "and", we can do something |
b6cc0a72 | 3447 | if the comparisons are EQ_EXPR. I.e., |
6d716ca8 RS |
3448 | (a->b == 2 && a->c == 4) can become (a->new == NEW). |
3449 | ||
3450 | WANTED_CODE is this operation code. For single bit fields, we can | |
3451 | convert EQ_EXPR to NE_EXPR so we need not reject the "wrong" | |
3452 | comparison for one-bit fields. */ | |
3453 | ||
b2215d83 | 3454 | enum tree_code wanted_code; |
6d716ca8 | 3455 | enum tree_code lcode, rcode; |
b2215d83 | 3456 | tree ll_arg, lr_arg, rl_arg, rr_arg; |
6d716ca8 | 3457 | tree ll_inner, lr_inner, rl_inner, rr_inner; |
770ae6cc RK |
3458 | HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos; |
3459 | HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos; | |
3460 | HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos; | |
3461 | HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos; | |
6d716ca8 RS |
3462 | int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp; |
3463 | enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode; | |
3464 | enum machine_mode lnmode, rnmode; | |
3465 | tree ll_mask, lr_mask, rl_mask, rr_mask; | |
d4453ee5 | 3466 | tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask; |
b2215d83 | 3467 | tree l_const, r_const; |
bd910dcf | 3468 | tree lntype, rntype, result; |
6d716ca8 | 3469 | int first_bit, end_bit; |
b2215d83 | 3470 | int volatilep; |
6d716ca8 | 3471 | |
ebde8a27 RK |
3472 | /* Start by getting the comparison codes. Fail if anything is volatile. |
3473 | If one operand is a BIT_AND_EXPR with the constant one, treat it as if | |
3474 | it were surrounded with a NE_EXPR. */ | |
6d716ca8 | 3475 | |
ebde8a27 | 3476 | if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs)) |
b2215d83 TW |
3477 | return 0; |
3478 | ||
6d716ca8 RS |
3479 | lcode = TREE_CODE (lhs); |
3480 | rcode = TREE_CODE (rhs); | |
ef659ec0 | 3481 | |
96d4cf0a RK |
3482 | if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1))) |
3483 | lcode = NE_EXPR, lhs = build (NE_EXPR, truth_type, lhs, integer_zero_node); | |
3484 | ||
3485 | if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1))) | |
3486 | rcode = NE_EXPR, rhs = build (NE_EXPR, truth_type, rhs, integer_zero_node); | |
3487 | ||
ebde8a27 | 3488 | if (TREE_CODE_CLASS (lcode) != '<' || TREE_CODE_CLASS (rcode) != '<') |
ef659ec0 TW |
3489 | return 0; |
3490 | ||
b2215d83 | 3491 | code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR) |
9c0ae98b | 3492 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR); |
b2215d83 TW |
3493 | |
3494 | ll_arg = TREE_OPERAND (lhs, 0); | |
3495 | lr_arg = TREE_OPERAND (lhs, 1); | |
3496 | rl_arg = TREE_OPERAND (rhs, 0); | |
3497 | rr_arg = TREE_OPERAND (rhs, 1); | |
b6cc0a72 | 3498 | |
8227896c | 3499 | /* If the RHS can be evaluated unconditionally and its operands are |
b2215d83 TW |
3500 | simple, it wins to evaluate the RHS unconditionally on machines |
3501 | with expensive branches. In this case, this isn't a comparison | |
1d691c53 RK |
3502 | that can be merged. Avoid doing this if the RHS is a floating-point |
3503 | comparison since those can trap. */ | |
b2215d83 TW |
3504 | |
3505 | if (BRANCH_COST >= 2 | |
1d691c53 | 3506 | && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg)) |
b2215d83 | 3507 | && simple_operand_p (rl_arg) |
8227896c | 3508 | && simple_operand_p (rr_arg)) |
01c58f26 RS |
3509 | { |
3510 | /* Convert (a != 0) || (b != 0) into (a | b) != 0. */ | |
3511 | if (code == TRUTH_OR_EXPR | |
3512 | && lcode == NE_EXPR && integer_zerop (lr_arg) | |
3513 | && rcode == NE_EXPR && integer_zerop (rr_arg) | |
3514 | && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)) | |
3515 | return build (NE_EXPR, truth_type, | |
3516 | build (BIT_IOR_EXPR, TREE_TYPE (ll_arg), | |
3517 | ll_arg, rl_arg), | |
3518 | integer_zero_node); | |
3519 | ||
3520 | /* Convert (a == 0) && (b == 0) into (a | b) == 0. */ | |
3521 | if (code == TRUTH_AND_EXPR | |
3522 | && lcode == EQ_EXPR && integer_zerop (lr_arg) | |
3523 | && rcode == EQ_EXPR && integer_zerop (rr_arg) | |
3524 | && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)) | |
3525 | return build (EQ_EXPR, truth_type, | |
3526 | build (BIT_IOR_EXPR, TREE_TYPE (ll_arg), | |
3527 | ll_arg, rl_arg), | |
3528 | integer_zero_node); | |
3529 | ||
3530 | return build (code, truth_type, lhs, rhs); | |
3531 | } | |
b2215d83 | 3532 | |
ef659ec0 TW |
3533 | /* See if the comparisons can be merged. Then get all the parameters for |
3534 | each side. */ | |
3535 | ||
6d716ca8 | 3536 | if ((lcode != EQ_EXPR && lcode != NE_EXPR) |
ef659ec0 | 3537 | || (rcode != EQ_EXPR && rcode != NE_EXPR)) |
6d716ca8 RS |
3538 | return 0; |
3539 | ||
b2215d83 TW |
3540 | volatilep = 0; |
3541 | ll_inner = decode_field_reference (ll_arg, | |
6d716ca8 | 3542 | &ll_bitsize, &ll_bitpos, &ll_mode, |
d4453ee5 RK |
3543 | &ll_unsignedp, &volatilep, &ll_mask, |
3544 | &ll_and_mask); | |
b2215d83 | 3545 | lr_inner = decode_field_reference (lr_arg, |
6d716ca8 | 3546 | &lr_bitsize, &lr_bitpos, &lr_mode, |
d4453ee5 RK |
3547 | &lr_unsignedp, &volatilep, &lr_mask, |
3548 | &lr_and_mask); | |
b2215d83 | 3549 | rl_inner = decode_field_reference (rl_arg, |
6d716ca8 | 3550 | &rl_bitsize, &rl_bitpos, &rl_mode, |
d4453ee5 RK |
3551 | &rl_unsignedp, &volatilep, &rl_mask, |
3552 | &rl_and_mask); | |
b2215d83 | 3553 | rr_inner = decode_field_reference (rr_arg, |
6d716ca8 | 3554 | &rr_bitsize, &rr_bitpos, &rr_mode, |
d4453ee5 RK |
3555 | &rr_unsignedp, &volatilep, &rr_mask, |
3556 | &rr_and_mask); | |
6d716ca8 RS |
3557 | |
3558 | /* It must be true that the inner operation on the lhs of each | |
3559 | comparison must be the same if we are to be able to do anything. | |
3560 | Then see if we have constants. If not, the same must be true for | |
3561 | the rhs's. */ | |
3562 | if (volatilep || ll_inner == 0 || rl_inner == 0 | |
3563 | || ! operand_equal_p (ll_inner, rl_inner, 0)) | |
3564 | return 0; | |
3565 | ||
b2215d83 TW |
3566 | if (TREE_CODE (lr_arg) == INTEGER_CST |
3567 | && TREE_CODE (rr_arg) == INTEGER_CST) | |
3568 | l_const = lr_arg, r_const = rr_arg; | |
6d716ca8 RS |
3569 | else if (lr_inner == 0 || rr_inner == 0 |
3570 | || ! operand_equal_p (lr_inner, rr_inner, 0)) | |
3571 | return 0; | |
b2215d83 TW |
3572 | else |
3573 | l_const = r_const = 0; | |
6d716ca8 RS |
3574 | |
3575 | /* If either comparison code is not correct for our logical operation, | |
3576 | fail. However, we can convert a one-bit comparison against zero into | |
3577 | the opposite comparison against that bit being set in the field. */ | |
b2215d83 | 3578 | |
9c0ae98b | 3579 | wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR); |
6d716ca8 RS |
3580 | if (lcode != wanted_code) |
3581 | { | |
3582 | if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask)) | |
5a6b3365 | 3583 | { |
2bd21a02 AS |
3584 | /* Make the left operand unsigned, since we are only interested |
3585 | in the value of one bit. Otherwise we are doing the wrong | |
3586 | thing below. */ | |
3587 | ll_unsignedp = 1; | |
71a874cd | 3588 | l_const = ll_mask; |
5a6b3365 | 3589 | } |
6d716ca8 RS |
3590 | else |
3591 | return 0; | |
3592 | } | |
3593 | ||
71a874cd | 3594 | /* This is analogous to the code for l_const above. */ |
6d716ca8 RS |
3595 | if (rcode != wanted_code) |
3596 | { | |
3597 | if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask)) | |
5a6b3365 | 3598 | { |
2bd21a02 | 3599 | rl_unsignedp = 1; |
71a874cd | 3600 | r_const = rl_mask; |
5a6b3365 | 3601 | } |
6d716ca8 RS |
3602 | else |
3603 | return 0; | |
3604 | } | |
3605 | ||
3606 | /* See if we can find a mode that contains both fields being compared on | |
3607 | the left. If we can't, fail. Otherwise, update all constants and masks | |
3608 | to be relative to a field of that size. */ | |
3609 | first_bit = MIN (ll_bitpos, rl_bitpos); | |
3610 | end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize); | |
3611 | lnmode = get_best_mode (end_bit - first_bit, first_bit, | |
3612 | TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode, | |
3613 | volatilep); | |
3614 | if (lnmode == VOIDmode) | |
3615 | return 0; | |
3616 | ||
3617 | lnbitsize = GET_MODE_BITSIZE (lnmode); | |
3618 | lnbitpos = first_bit & ~ (lnbitsize - 1); | |
b0c48229 | 3619 | lntype = (*lang_hooks.types.type_for_size) (lnbitsize, 1); |
6d716ca8 RS |
3620 | xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos; |
3621 | ||
f76b9db2 ILT |
3622 | if (BYTES_BIG_ENDIAN) |
3623 | { | |
3624 | xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize; | |
3625 | xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize; | |
3626 | } | |
6d716ca8 | 3627 | |
bd910dcf | 3628 | ll_mask = const_binop (LSHIFT_EXPR, convert (lntype, ll_mask), |
91d33e36 | 3629 | size_int (xll_bitpos), 0); |
bd910dcf | 3630 | rl_mask = const_binop (LSHIFT_EXPR, convert (lntype, rl_mask), |
91d33e36 | 3631 | size_int (xrl_bitpos), 0); |
6d716ca8 | 3632 | |
6d716ca8 RS |
3633 | if (l_const) |
3634 | { | |
bd910dcf | 3635 | l_const = convert (lntype, l_const); |
b6cc0a72 | 3636 | l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask); |
02103577 RK |
3637 | l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos), 0); |
3638 | if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const, | |
3639 | fold (build1 (BIT_NOT_EXPR, | |
bd910dcf | 3640 | lntype, ll_mask)), |
02103577 RK |
3641 | 0))) |
3642 | { | |
ab87f8c8 | 3643 | warning ("comparison is always %d", wanted_code == NE_EXPR); |
b6cc0a72 | 3644 | |
02103577 RK |
3645 | return convert (truth_type, |
3646 | wanted_code == NE_EXPR | |
3647 | ? integer_one_node : integer_zero_node); | |
3648 | } | |
6d716ca8 RS |
3649 | } |
3650 | if (r_const) | |
3651 | { | |
bd910dcf | 3652 | r_const = convert (lntype, r_const); |
d4453ee5 | 3653 | r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask); |
02103577 RK |
3654 | r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos), 0); |
3655 | if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const, | |
3656 | fold (build1 (BIT_NOT_EXPR, | |
bd910dcf | 3657 | lntype, rl_mask)), |
02103577 RK |
3658 | 0))) |
3659 | { | |
ab87f8c8 JL |
3660 | warning ("comparison is always %d", wanted_code == NE_EXPR); |
3661 | ||
02103577 RK |
3662 | return convert (truth_type, |
3663 | wanted_code == NE_EXPR | |
3664 | ? integer_one_node : integer_zero_node); | |
3665 | } | |
6d716ca8 RS |
3666 | } |
3667 | ||
3668 | /* If the right sides are not constant, do the same for it. Also, | |
3669 | disallow this optimization if a size or signedness mismatch occurs | |
3670 | between the left and right sides. */ | |
3671 | if (l_const == 0) | |
3672 | { | |
3673 | if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize | |
e6a28f26 RS |
3674 | || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp |
3675 | /* Make sure the two fields on the right | |
3676 | correspond to the left without being swapped. */ | |
3677 | || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos) | |
6d716ca8 RS |
3678 | return 0; |
3679 | ||
3680 | first_bit = MIN (lr_bitpos, rr_bitpos); | |
3681 | end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize); | |
3682 | rnmode = get_best_mode (end_bit - first_bit, first_bit, | |
3683 | TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode, | |
3684 | volatilep); | |
3685 | if (rnmode == VOIDmode) | |
3686 | return 0; | |
3687 | ||
3688 | rnbitsize = GET_MODE_BITSIZE (rnmode); | |
3689 | rnbitpos = first_bit & ~ (rnbitsize - 1); | |
b0c48229 | 3690 | rntype = (*lang_hooks.types.type_for_size) (rnbitsize, 1); |
6d716ca8 RS |
3691 | xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos; |
3692 | ||
f76b9db2 ILT |
3693 | if (BYTES_BIG_ENDIAN) |
3694 | { | |
3695 | xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize; | |
3696 | xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize; | |
3697 | } | |
6d716ca8 | 3698 | |
bd910dcf | 3699 | lr_mask = const_binop (LSHIFT_EXPR, convert (rntype, lr_mask), |
91d33e36 | 3700 | size_int (xlr_bitpos), 0); |
bd910dcf | 3701 | rr_mask = const_binop (LSHIFT_EXPR, convert (rntype, rr_mask), |
91d33e36 | 3702 | size_int (xrr_bitpos), 0); |
6d716ca8 RS |
3703 | |
3704 | /* Make a mask that corresponds to both fields being compared. | |
11a86c56 CH |
3705 | Do this for both items being compared. If the operands are the |
3706 | same size and the bits being compared are in the same position | |
3707 | then we can do this by masking both and comparing the masked | |
3708 | results. */ | |
91d33e36 RS |
3709 | ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0); |
3710 | lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask, 0); | |
11a86c56 | 3711 | if (lnbitsize == rnbitsize && xll_bitpos == xlr_bitpos) |
6d716ca8 | 3712 | { |
bd910dcf | 3713 | lhs = make_bit_field_ref (ll_inner, lntype, lnbitsize, lnbitpos, |
6d716ca8 | 3714 | ll_unsignedp || rl_unsignedp); |
11a86c56 CH |
3715 | if (! all_ones_mask_p (ll_mask, lnbitsize)) |
3716 | lhs = build (BIT_AND_EXPR, lntype, lhs, ll_mask); | |
3717 | ||
bd910dcf | 3718 | rhs = make_bit_field_ref (lr_inner, rntype, rnbitsize, rnbitpos, |
6d716ca8 | 3719 | lr_unsignedp || rr_unsignedp); |
11a86c56 CH |
3720 | if (! all_ones_mask_p (lr_mask, rnbitsize)) |
3721 | rhs = build (BIT_AND_EXPR, rntype, rhs, lr_mask); | |
3722 | ||
6d716ca8 RS |
3723 | return build (wanted_code, truth_type, lhs, rhs); |
3724 | } | |
3725 | ||
3726 | /* There is still another way we can do something: If both pairs of | |
3727 | fields being compared are adjacent, we may be able to make a wider | |
97ea7176 CH |
3728 | field containing them both. |
3729 | ||
3730 | Note that we still must mask the lhs/rhs expressions. Furthermore, | |
b6cc0a72 | 3731 | the mask must be shifted to account for the shift done by |
97ea7176 | 3732 | make_bit_field_ref. */ |
6d716ca8 RS |
3733 | if ((ll_bitsize + ll_bitpos == rl_bitpos |
3734 | && lr_bitsize + lr_bitpos == rr_bitpos) | |
3735 | || (ll_bitpos == rl_bitpos + rl_bitsize | |
3736 | && lr_bitpos == rr_bitpos + rr_bitsize)) | |
97ea7176 | 3737 | { |
bd910dcf CH |
3738 | tree type; |
3739 | ||
3740 | lhs = make_bit_field_ref (ll_inner, lntype, ll_bitsize + rl_bitsize, | |
97ea7176 | 3741 | MIN (ll_bitpos, rl_bitpos), ll_unsignedp); |
bd910dcf CH |
3742 | rhs = make_bit_field_ref (lr_inner, rntype, lr_bitsize + rr_bitsize, |
3743 | MIN (lr_bitpos, rr_bitpos), lr_unsignedp); | |
3744 | ||
97ea7176 CH |
3745 | ll_mask = const_binop (RSHIFT_EXPR, ll_mask, |
3746 | size_int (MIN (xll_bitpos, xrl_bitpos)), 0); | |
bd910dcf CH |
3747 | lr_mask = const_binop (RSHIFT_EXPR, lr_mask, |
3748 | size_int (MIN (xlr_bitpos, xrr_bitpos)), 0); | |
3749 | ||
3750 | /* Convert to the smaller type before masking out unwanted bits. */ | |
3751 | type = lntype; | |
3752 | if (lntype != rntype) | |
3753 | { | |
3754 | if (lnbitsize > rnbitsize) | |
3755 | { | |
3756 | lhs = convert (rntype, lhs); | |
3757 | ll_mask = convert (rntype, ll_mask); | |
3758 | type = rntype; | |
3759 | } | |
3760 | else if (lnbitsize < rnbitsize) | |
3761 | { | |
3762 | rhs = convert (lntype, rhs); | |
3763 | lr_mask = convert (lntype, lr_mask); | |
3764 | type = lntype; | |
3765 | } | |
3766 | } | |
3767 | ||
97ea7176 CH |
3768 | if (! all_ones_mask_p (ll_mask, ll_bitsize + rl_bitsize)) |
3769 | lhs = build (BIT_AND_EXPR, type, lhs, ll_mask); | |
3770 | ||
97ea7176 CH |
3771 | if (! all_ones_mask_p (lr_mask, lr_bitsize + rr_bitsize)) |
3772 | rhs = build (BIT_AND_EXPR, type, rhs, lr_mask); | |
3773 | ||
3774 | return build (wanted_code, truth_type, lhs, rhs); | |
3775 | } | |
6d716ca8 RS |
3776 | |
3777 | return 0; | |
3778 | } | |
3779 | ||
3780 | /* Handle the case of comparisons with constants. If there is something in | |
3781 | common between the masks, those bits of the constants must be the same. | |
3782 | If not, the condition is always false. Test for this to avoid generating | |
3783 | incorrect code below. */ | |
91d33e36 | 3784 | result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask, 0); |
6d716ca8 | 3785 | if (! integer_zerop (result) |
91d33e36 RS |
3786 | && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const, 0), |
3787 | const_binop (BIT_AND_EXPR, result, r_const, 0)) != 1) | |
6d716ca8 RS |
3788 | { |
3789 | if (wanted_code == NE_EXPR) | |
3790 | { | |
3791 | warning ("`or' of unmatched not-equal tests is always 1"); | |
3792 | return convert (truth_type, integer_one_node); | |
3793 | } | |
3794 | else | |
3795 | { | |
ab87f8c8 | 3796 | warning ("`and' of mutually exclusive equal-tests is always 0"); |
6d716ca8 RS |
3797 | return convert (truth_type, integer_zero_node); |
3798 | } | |
3799 | } | |
3800 | ||
3801 | /* Construct the expression we will return. First get the component | |
3802 | reference we will make. Unless the mask is all ones the width of | |
3803 | that field, perform the mask operation. Then compare with the | |
3804 | merged constant. */ | |
bd910dcf | 3805 | result = make_bit_field_ref (ll_inner, lntype, lnbitsize, lnbitpos, |
6d716ca8 RS |
3806 | ll_unsignedp || rl_unsignedp); |
3807 | ||
91d33e36 | 3808 | ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0); |
6d716ca8 | 3809 | if (! all_ones_mask_p (ll_mask, lnbitsize)) |
bd910dcf | 3810 | result = build (BIT_AND_EXPR, lntype, result, ll_mask); |
6d716ca8 RS |
3811 | |
3812 | return build (wanted_code, truth_type, result, | |
91d33e36 | 3813 | const_binop (BIT_IOR_EXPR, l_const, r_const, 0)); |
6d716ca8 RS |
3814 | } |
3815 | \f | |
b6cc0a72 | 3816 | /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a |
14a774a9 RK |
3817 | constant. */ |
3818 | ||
3819 | static tree | |
3820 | optimize_minmax_comparison (t) | |
3821 | tree t; | |
3822 | { | |
3823 | tree type = TREE_TYPE (t); | |
3824 | tree arg0 = TREE_OPERAND (t, 0); | |
3825 | enum tree_code op_code; | |
3826 | tree comp_const = TREE_OPERAND (t, 1); | |
3827 | tree minmax_const; | |
3828 | int consts_equal, consts_lt; | |
3829 | tree inner; | |
3830 | ||
3831 | STRIP_SIGN_NOPS (arg0); | |
3832 | ||
3833 | op_code = TREE_CODE (arg0); | |
3834 | minmax_const = TREE_OPERAND (arg0, 1); | |
3835 | consts_equal = tree_int_cst_equal (minmax_const, comp_const); | |
3836 | consts_lt = tree_int_cst_lt (minmax_const, comp_const); | |
3837 | inner = TREE_OPERAND (arg0, 0); | |
3838 | ||
3839 | /* If something does not permit us to optimize, return the original tree. */ | |
3840 | if ((op_code != MIN_EXPR && op_code != MAX_EXPR) | |
3841 | || TREE_CODE (comp_const) != INTEGER_CST | |
3842 | || TREE_CONSTANT_OVERFLOW (comp_const) | |
3843 | || TREE_CODE (minmax_const) != INTEGER_CST | |
3844 | || TREE_CONSTANT_OVERFLOW (minmax_const)) | |
3845 | return t; | |
3846 | ||
3847 | /* Now handle all the various comparison codes. We only handle EQ_EXPR | |
3848 | and GT_EXPR, doing the rest with recursive calls using logical | |
3849 | simplifications. */ | |
3850 | switch (TREE_CODE (t)) | |
3851 | { | |
3852 | case NE_EXPR: case LT_EXPR: case LE_EXPR: | |
3853 | return | |
3854 | invert_truthvalue (optimize_minmax_comparison (invert_truthvalue (t))); | |
3855 | ||
3856 | case GE_EXPR: | |
3857 | return | |
3858 | fold (build (TRUTH_ORIF_EXPR, type, | |
3859 | optimize_minmax_comparison | |
3860 | (build (EQ_EXPR, type, arg0, comp_const)), | |
3861 | optimize_minmax_comparison | |
3862 | (build (GT_EXPR, type, arg0, comp_const)))); | |
3863 | ||
3864 | case EQ_EXPR: | |
3865 | if (op_code == MAX_EXPR && consts_equal) | |
3866 | /* MAX (X, 0) == 0 -> X <= 0 */ | |
3867 | return fold (build (LE_EXPR, type, inner, comp_const)); | |
3868 | ||
3869 | else if (op_code == MAX_EXPR && consts_lt) | |
3870 | /* MAX (X, 0) == 5 -> X == 5 */ | |
3871 | return fold (build (EQ_EXPR, type, inner, comp_const)); | |
3872 | ||
3873 | else if (op_code == MAX_EXPR) | |
3874 | /* MAX (X, 0) == -1 -> false */ | |
3875 | return omit_one_operand (type, integer_zero_node, inner); | |
3876 | ||
3877 | else if (consts_equal) | |
3878 | /* MIN (X, 0) == 0 -> X >= 0 */ | |
3879 | return fold (build (GE_EXPR, type, inner, comp_const)); | |
3880 | ||
3881 | else if (consts_lt) | |
3882 | /* MIN (X, 0) == 5 -> false */ | |
3883 | return omit_one_operand (type, integer_zero_node, inner); | |
3884 | ||
3885 | else | |
3886 | /* MIN (X, 0) == -1 -> X == -1 */ | |
3887 | return fold (build (EQ_EXPR, type, inner, comp_const)); | |
3888 | ||
3889 | case GT_EXPR: | |
3890 | if (op_code == MAX_EXPR && (consts_equal || consts_lt)) | |
3891 | /* MAX (X, 0) > 0 -> X > 0 | |
3892 | MAX (X, 0) > 5 -> X > 5 */ | |
3893 | return fold (build (GT_EXPR, type, inner, comp_const)); | |
3894 | ||
3895 | else if (op_code == MAX_EXPR) | |
3896 | /* MAX (X, 0) > -1 -> true */ | |
3897 | return omit_one_operand (type, integer_one_node, inner); | |
3898 | ||
3899 | else if (op_code == MIN_EXPR && (consts_equal || consts_lt)) | |
3900 | /* MIN (X, 0) > 0 -> false | |
3901 | MIN (X, 0) > 5 -> false */ | |
3902 | return omit_one_operand (type, integer_zero_node, inner); | |
3903 | ||
3904 | else | |
3905 | /* MIN (X, 0) > -1 -> X > -1 */ | |
3906 | return fold (build (GT_EXPR, type, inner, comp_const)); | |
3907 | ||
3908 | default: | |
3909 | return t; | |
3910 | } | |
3911 | } | |
3912 | \f | |
1baa375f RK |
3913 | /* T is an integer expression that is being multiplied, divided, or taken a |
3914 | modulus (CODE says which and what kind of divide or modulus) by a | |
3915 | constant C. See if we can eliminate that operation by folding it with | |
3916 | other operations already in T. WIDE_TYPE, if non-null, is a type that | |
3917 | should be used for the computation if wider than our type. | |
3918 | ||
cff27795 EB |
3919 | For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return |
3920 | (X * 2) + (Y * 4). We must, however, be assured that either the original | |
8e1ca098 RH |
3921 | expression would not overflow or that overflow is undefined for the type |
3922 | in the language in question. | |
3923 | ||
3924 | We also canonicalize (X + 7) * 4 into X * 4 + 28 in the hope that either | |
3925 | the machine has a multiply-accumulate insn or that this is part of an | |
3926 | addressing calculation. | |
1baa375f RK |
3927 | |
3928 | If we return a non-null expression, it is an equivalent form of the | |
3929 | original computation, but need not be in the original type. */ | |
3930 | ||
3931 | static tree | |
3932 | extract_muldiv (t, c, code, wide_type) | |
3933 | tree t; | |
3934 | tree c; | |
3935 | enum tree_code code; | |
3936 | tree wide_type; | |
3937 | { | |
3938 | tree type = TREE_TYPE (t); | |
3939 | enum tree_code tcode = TREE_CODE (t); | |
b6cc0a72 | 3940 | tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type)) |
1baa375f RK |
3941 | > GET_MODE_SIZE (TYPE_MODE (type))) |
3942 | ? wide_type : type); | |
3943 | tree t1, t2; | |
3944 | int same_p = tcode == code; | |
9d0878fd | 3945 | tree op0 = NULL_TREE, op1 = NULL_TREE; |
1baa375f RK |
3946 | |
3947 | /* Don't deal with constants of zero here; they confuse the code below. */ | |
3948 | if (integer_zerop (c)) | |
8e1ca098 | 3949 | return NULL_TREE; |
1baa375f RK |
3950 | |
3951 | if (TREE_CODE_CLASS (tcode) == '1') | |
3952 | op0 = TREE_OPERAND (t, 0); | |
3953 | ||
3954 | if (TREE_CODE_CLASS (tcode) == '2') | |
3955 | op0 = TREE_OPERAND (t, 0), op1 = TREE_OPERAND (t, 1); | |
3956 | ||
3957 | /* Note that we need not handle conditional operations here since fold | |
3958 | already handles those cases. So just do arithmetic here. */ | |
3959 | switch (tcode) | |
3960 | { | |
3961 | case INTEGER_CST: | |
3962 | /* For a constant, we can always simplify if we are a multiply | |
3963 | or (for divide and modulus) if it is a multiple of our constant. */ | |
3964 | if (code == MULT_EXPR | |
3965 | || integer_zerop (const_binop (TRUNC_MOD_EXPR, t, c, 0))) | |
3966 | return const_binop (code, convert (ctype, t), convert (ctype, c), 0); | |
3967 | break; | |
3968 | ||
3969 | case CONVERT_EXPR: case NON_LVALUE_EXPR: case NOP_EXPR: | |
eff9c80d RH |
3970 | /* If op0 is an expression, and is unsigned, and the type is |
3971 | smaller than ctype, then we cannot widen the expression. */ | |
3972 | if ((TREE_CODE_CLASS (TREE_CODE (op0)) == '<' | |
3973 | || TREE_CODE_CLASS (TREE_CODE (op0)) == '1' | |
3974 | || TREE_CODE_CLASS (TREE_CODE (op0)) == '2' | |
3975 | || TREE_CODE_CLASS (TREE_CODE (op0)) == 'e') | |
3976 | && TREE_UNSIGNED (TREE_TYPE (op0)) | |
7393c642 RK |
3977 | && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE |
3978 | && TYPE_IS_SIZETYPE (TREE_TYPE (op0))) | |
eff9c80d | 3979 | && (GET_MODE_SIZE (TYPE_MODE (ctype)) |
dd3f0101 | 3980 | > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0))))) |
eff9c80d RH |
3981 | break; |
3982 | ||
1baa375f | 3983 | /* Pass the constant down and see if we can make a simplification. If |
59adecfa RK |
3984 | we can, replace this expression with the inner simplification for |
3985 | possible later conversion to our or some other type. */ | |
1baa375f RK |
3986 | if (0 != (t1 = extract_muldiv (op0, convert (TREE_TYPE (op0), c), code, |
3987 | code == MULT_EXPR ? ctype : NULL_TREE))) | |
3988 | return t1; | |
3989 | break; | |
3990 | ||
3991 | case NEGATE_EXPR: case ABS_EXPR: | |
3992 | if ((t1 = extract_muldiv (op0, c, code, wide_type)) != 0) | |
3993 | return fold (build1 (tcode, ctype, convert (ctype, t1))); | |
3994 | break; | |
3995 | ||
3996 | case MIN_EXPR: case MAX_EXPR: | |
13393c8a JW |
3997 | /* If widening the type changes the signedness, then we can't perform |
3998 | this optimization as that changes the result. */ | |
eff9c80d | 3999 | if (TREE_UNSIGNED (ctype) != TREE_UNSIGNED (type)) |
13393c8a JW |
4000 | break; |
4001 | ||
1baa375f RK |
4002 | /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */ |
4003 | if ((t1 = extract_muldiv (op0, c, code, wide_type)) != 0 | |
4004 | && (t2 = extract_muldiv (op1, c, code, wide_type)) != 0) | |
59adecfa RK |
4005 | { |
4006 | if (tree_int_cst_sgn (c) < 0) | |
4007 | tcode = (tcode == MIN_EXPR ? MAX_EXPR : MIN_EXPR); | |
4008 | ||
4009 | return fold (build (tcode, ctype, convert (ctype, t1), | |
4010 | convert (ctype, t2))); | |
4011 | } | |
1baa375f RK |
4012 | break; |
4013 | ||
4014 | case WITH_RECORD_EXPR: | |
4015 | if ((t1 = extract_muldiv (TREE_OPERAND (t, 0), c, code, wide_type)) != 0) | |
4016 | return build (WITH_RECORD_EXPR, TREE_TYPE (t1), t1, | |
4017 | TREE_OPERAND (t, 1)); | |
4018 | break; | |
4019 | ||
4020 | case SAVE_EXPR: | |
59adecfa RK |
4021 | /* If this has not been evaluated and the operand has no side effects, |
4022 | we can see if we can do something inside it and make a new one. | |
4023 | Note that this test is overly conservative since we can do this | |
4024 | if the only reason it had side effects is that it was another | |
4025 | similar SAVE_EXPR, but that isn't worth bothering with. */ | |
4026 | if (SAVE_EXPR_RTL (t) == 0 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)) | |
1baa375f RK |
4027 | && 0 != (t1 = extract_muldiv (TREE_OPERAND (t, 0), c, code, |
4028 | wide_type))) | |
fe375cf1 JJ |
4029 | { |
4030 | t1 = save_expr (t1); | |
4031 | if (SAVE_EXPR_PERSISTENT_P (t) && TREE_CODE (t1) == SAVE_EXPR) | |
4032 | SAVE_EXPR_PERSISTENT_P (t1) = 1; | |
4033 | if (is_pending_size (t)) | |
4034 | put_pending_size (t1); | |
4035 | return t1; | |
4036 | } | |
1baa375f RK |
4037 | break; |
4038 | ||
4039 | case LSHIFT_EXPR: case RSHIFT_EXPR: | |
4040 | /* If the second operand is constant, this is a multiplication | |
4041 | or floor division, by a power of two, so we can treat it that | |
4042 | way unless the multiplier or divisor overflows. */ | |
4043 | if (TREE_CODE (op1) == INTEGER_CST | |
d08230fe NC |
4044 | /* const_binop may not detect overflow correctly, |
4045 | so check for it explicitly here. */ | |
4046 | && TYPE_PRECISION (TREE_TYPE (size_one_node)) > TREE_INT_CST_LOW (op1) | |
4047 | && TREE_INT_CST_HIGH (op1) == 0 | |
1baa375f RK |
4048 | && 0 != (t1 = convert (ctype, |
4049 | const_binop (LSHIFT_EXPR, size_one_node, | |
4050 | op1, 0))) | |
4051 | && ! TREE_OVERFLOW (t1)) | |
4052 | return extract_muldiv (build (tcode == LSHIFT_EXPR | |
4053 | ? MULT_EXPR : FLOOR_DIV_EXPR, | |
4054 | ctype, convert (ctype, op0), t1), | |
4055 | c, code, wide_type); | |
4056 | break; | |
4057 | ||
4058 | case PLUS_EXPR: case MINUS_EXPR: | |
4059 | /* See if we can eliminate the operation on both sides. If we can, we | |
4060 | can return a new PLUS or MINUS. If we can't, the only remaining | |
4061 | cases where we can do anything are if the second operand is a | |
4062 | constant. */ | |
4063 | t1 = extract_muldiv (op0, c, code, wide_type); | |
4064 | t2 = extract_muldiv (op1, c, code, wide_type); | |
fba2c0cd JJ |
4065 | if (t1 != 0 && t2 != 0 |
4066 | && (code == MULT_EXPR | |
4067 | /* If not multiplication, we can only do this if either operand | |
4068 | is divisible by c. */ | |
4069 | || multiple_of_p (ctype, op0, c) | |
4070 | || multiple_of_p (ctype, op1, c))) | |
1baa375f RK |
4071 | return fold (build (tcode, ctype, convert (ctype, t1), |
4072 | convert (ctype, t2))); | |
1baa375f | 4073 | |
59adecfa RK |
4074 | /* If this was a subtraction, negate OP1 and set it to be an addition. |
4075 | This simplifies the logic below. */ | |
4076 | if (tcode == MINUS_EXPR) | |
4077 | tcode = PLUS_EXPR, op1 = negate_expr (op1); | |
4078 | ||
f9011d04 RK |
4079 | if (TREE_CODE (op1) != INTEGER_CST) |
4080 | break; | |
4081 | ||
59adecfa RK |
4082 | /* If either OP1 or C are negative, this optimization is not safe for |
4083 | some of the division and remainder types while for others we need | |
4084 | to change the code. */ | |
4085 | if (tree_int_cst_sgn (op1) < 0 || tree_int_cst_sgn (c) < 0) | |
4086 | { | |
4087 | if (code == CEIL_DIV_EXPR) | |
4088 | code = FLOOR_DIV_EXPR; | |
59adecfa RK |
4089 | else if (code == FLOOR_DIV_EXPR) |
4090 | code = CEIL_DIV_EXPR; | |
0629440f RK |
4091 | else if (code != MULT_EXPR |
4092 | && code != CEIL_MOD_EXPR && code != FLOOR_MOD_EXPR) | |
59adecfa RK |
4093 | break; |
4094 | } | |
4095 | ||
12644a9a TM |
4096 | /* If it's a multiply or a division/modulus operation of a multiple |
4097 | of our constant, do the operation and verify it doesn't overflow. */ | |
4098 | if (code == MULT_EXPR | |
4099 | || integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0))) | |
dd3f0101 KH |
4100 | { |
4101 | op1 = const_binop (code, convert (ctype, op1), convert (ctype, c), 0); | |
4102 | if (op1 == 0 || TREE_OVERFLOW (op1)) | |
4103 | break; | |
4104 | } | |
12644a9a | 4105 | else |
dd3f0101 | 4106 | break; |
59adecfa | 4107 | |
23cdce68 RH |
4108 | /* If we have an unsigned type is not a sizetype, we cannot widen |
4109 | the operation since it will change the result if the original | |
4110 | computation overflowed. */ | |
4111 | if (TREE_UNSIGNED (ctype) | |
7393c642 | 4112 | && ! (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)) |
23cdce68 RH |
4113 | && ctype != type) |
4114 | break; | |
4115 | ||
1baa375f | 4116 | /* If we were able to eliminate our operation from the first side, |
59adecfa RK |
4117 | apply our operation to the second side and reform the PLUS. */ |
4118 | if (t1 != 0 && (TREE_CODE (t1) != code || code == MULT_EXPR)) | |
4119 | return fold (build (tcode, ctype, convert (ctype, t1), op1)); | |
1baa375f RK |
4120 | |
4121 | /* The last case is if we are a multiply. In that case, we can | |
4122 | apply the distributive law to commute the multiply and addition | |
30f7a378 | 4123 | if the multiplication of the constants doesn't overflow. */ |
59adecfa | 4124 | if (code == MULT_EXPR) |
1baa375f RK |
4125 | return fold (build (tcode, ctype, fold (build (code, ctype, |
4126 | convert (ctype, op0), | |
4127 | convert (ctype, c))), | |
59adecfa | 4128 | op1)); |
1baa375f RK |
4129 | |
4130 | break; | |
4131 | ||
4132 | case MULT_EXPR: | |
4133 | /* We have a special case here if we are doing something like | |
4134 | (C * 8) % 4 since we know that's zero. */ | |
4135 | if ((code == TRUNC_MOD_EXPR || code == CEIL_MOD_EXPR | |
4136 | || code == FLOOR_MOD_EXPR || code == ROUND_MOD_EXPR) | |
4137 | && TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST | |
4138 | && integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0))) | |
4139 | return omit_one_operand (type, integer_zero_node, op0); | |
4140 | ||
30f7a378 | 4141 | /* ... fall through ... */ |
1baa375f RK |
4142 | |
4143 | case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR: | |
4144 | case ROUND_DIV_EXPR: case EXACT_DIV_EXPR: | |
4145 | /* If we can extract our operation from the LHS, do so and return a | |
4146 | new operation. Likewise for the RHS from a MULT_EXPR. Otherwise, | |
4147 | do something only if the second operand is a constant. */ | |
4148 | if (same_p | |
4149 | && (t1 = extract_muldiv (op0, c, code, wide_type)) != 0) | |
4150 | return fold (build (tcode, ctype, convert (ctype, t1), | |
4151 | convert (ctype, op1))); | |
4152 | else if (tcode == MULT_EXPR && code == MULT_EXPR | |
4153 | && (t1 = extract_muldiv (op1, c, code, wide_type)) != 0) | |
4154 | return fold (build (tcode, ctype, convert (ctype, op0), | |
4155 | convert (ctype, t1))); | |
4156 | else if (TREE_CODE (op1) != INTEGER_CST) | |
4157 | return 0; | |
4158 | ||
4159 | /* If these are the same operation types, we can associate them | |
4160 | assuming no overflow. */ | |
4161 | if (tcode == code | |
4162 | && 0 != (t1 = const_binop (MULT_EXPR, convert (ctype, op1), | |
4163 | convert (ctype, c), 0)) | |
4164 | && ! TREE_OVERFLOW (t1)) | |
4165 | return fold (build (tcode, ctype, convert (ctype, op0), t1)); | |
4166 | ||
4167 | /* If these operations "cancel" each other, we have the main | |
4168 | optimizations of this pass, which occur when either constant is a | |
4169 | multiple of the other, in which case we replace this with either an | |
b6cc0a72 | 4170 | operation or CODE or TCODE. |
8e1ca098 | 4171 | |
f5143c46 | 4172 | If we have an unsigned type that is not a sizetype, we cannot do |
8e1ca098 RH |
4173 | this since it will change the result if the original computation |
4174 | overflowed. */ | |
4175 | if ((! TREE_UNSIGNED (ctype) | |
7393c642 | 4176 | || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype))) |
8e1ca098 RH |
4177 | && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR) |
4178 | || (tcode == MULT_EXPR | |
4179 | && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR | |
4180 | && code != FLOOR_MOD_EXPR && code != ROUND_MOD_EXPR))) | |
1baa375f RK |
4181 | { |
4182 | if (integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0))) | |
4183 | return fold (build (tcode, ctype, convert (ctype, op0), | |
4184 | convert (ctype, | |
4185 | const_binop (TRUNC_DIV_EXPR, | |
4186 | op1, c, 0)))); | |
4187 | else if (integer_zerop (const_binop (TRUNC_MOD_EXPR, c, op1, 0))) | |
4188 | return fold (build (code, ctype, convert (ctype, op0), | |
4189 | convert (ctype, | |
4190 | const_binop (TRUNC_DIV_EXPR, | |
4191 | c, op1, 0)))); | |
4192 | } | |
4193 | break; | |
4194 | ||
4195 | default: | |
4196 | break; | |
4197 | } | |
4198 | ||
4199 | return 0; | |
4200 | } | |
4201 | \f | |
b5f3b6b6 RK |
4202 | /* If T contains a COMPOUND_EXPR which was inserted merely to evaluate |
4203 | S, a SAVE_EXPR, return the expression actually being evaluated. Note | |
4204 | that we may sometimes modify the tree. */ | |
4205 | ||
4206 | static tree | |
4207 | strip_compound_expr (t, s) | |
4208 | tree t; | |
4209 | tree s; | |
4210 | { | |
b5f3b6b6 RK |
4211 | enum tree_code code = TREE_CODE (t); |
4212 | ||
4213 | /* See if this is the COMPOUND_EXPR we want to eliminate. */ | |
4214 | if (code == COMPOUND_EXPR && TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR | |
4215 | && TREE_OPERAND (TREE_OPERAND (t, 0), 0) == s) | |
4216 | return TREE_OPERAND (t, 1); | |
4217 | ||
4218 | /* See if this is a COND_EXPR or a simple arithmetic operator. We | |
4219 | don't bother handling any other types. */ | |
4220 | else if (code == COND_EXPR) | |
4221 | { | |
4222 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
4223 | TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s); | |
4224 | TREE_OPERAND (t, 2) = strip_compound_expr (TREE_OPERAND (t, 2), s); | |
4225 | } | |
4226 | else if (TREE_CODE_CLASS (code) == '1') | |
4227 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
4228 | else if (TREE_CODE_CLASS (code) == '<' | |
4229 | || TREE_CODE_CLASS (code) == '2') | |
4230 | { | |
4231 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
4232 | TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s); | |
4233 | } | |
4234 | ||
4235 | return t; | |
4236 | } | |
4237 | \f | |
f628873f MM |
4238 | /* Return a node which has the indicated constant VALUE (either 0 or |
4239 | 1), and is of the indicated TYPE. */ | |
4240 | ||
83e0821b | 4241 | static tree |
f628873f MM |
4242 | constant_boolean_node (value, type) |
4243 | int value; | |
4244 | tree type; | |
4245 | { | |
4246 | if (type == integer_type_node) | |
4247 | return value ? integer_one_node : integer_zero_node; | |
4248 | else if (TREE_CODE (type) == BOOLEAN_TYPE) | |
78ef5b89 NB |
4249 | return (*lang_hooks.truthvalue_conversion) (value ? integer_one_node : |
4250 | integer_zero_node); | |
b6cc0a72 | 4251 | else |
f628873f MM |
4252 | { |
4253 | tree t = build_int_2 (value, 0); | |
d4b60170 | 4254 | |
f628873f MM |
4255 | TREE_TYPE (t) = type; |
4256 | return t; | |
4257 | } | |
4258 | } | |
4259 | ||
ab87f8c8 JL |
4260 | /* Utility function for the following routine, to see how complex a nesting of |
4261 | COND_EXPRs can be. EXPR is the expression and LIMIT is a count beyond which | |
4262 | we don't care (to avoid spending too much time on complex expressions.). */ | |
4263 | ||
4264 | static int | |
4265 | count_cond (expr, lim) | |
4266 | tree expr; | |
4267 | int lim; | |
4268 | { | |
d6edb99e | 4269 | int ctrue, cfalse; |
ab87f8c8 JL |
4270 | |
4271 | if (TREE_CODE (expr) != COND_EXPR) | |
4272 | return 0; | |
4273 | else if (lim <= 0) | |
4274 | return 0; | |
4275 | ||
d6edb99e ZW |
4276 | ctrue = count_cond (TREE_OPERAND (expr, 1), lim - 1); |
4277 | cfalse = count_cond (TREE_OPERAND (expr, 2), lim - 1 - ctrue); | |
4278 | return MIN (lim, 1 + ctrue + cfalse); | |
ab87f8c8 | 4279 | } |
68626d4f | 4280 | |
1f77b5da | 4281 | /* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'. |
68626d4f MM |
4282 | Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here |
4283 | CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)' | |
4284 | expression, and ARG to `a'. If COND_FIRST_P is non-zero, then the | |
4285 | COND is the first argument to CODE; otherwise (as in the example | |
4286 | given here), it is the second argument. TYPE is the type of the | |
4287 | original expression. */ | |
4288 | ||
4289 | static tree | |
4290 | fold_binary_op_with_conditional_arg (code, type, cond, arg, cond_first_p) | |
4291 | enum tree_code code; | |
4292 | tree type; | |
4293 | tree cond; | |
4294 | tree arg; | |
4295 | int cond_first_p; | |
4296 | { | |
4297 | tree test, true_value, false_value; | |
4298 | tree lhs = NULL_TREE; | |
4299 | tree rhs = NULL_TREE; | |
4300 | /* In the end, we'll produce a COND_EXPR. Both arms of the | |
4301 | conditional expression will be binary operations. The left-hand | |
4302 | side of the expression to be executed if the condition is true | |
4303 | will be pointed to by TRUE_LHS. Similarly, the right-hand side | |
4304 | of the expression to be executed if the condition is true will be | |
d6a7951f | 4305 | pointed to by TRUE_RHS. FALSE_LHS and FALSE_RHS are analogous -- |
68626d4f MM |
4306 | but apply to the expression to be executed if the conditional is |
4307 | false. */ | |
4308 | tree *true_lhs; | |
4309 | tree *true_rhs; | |
4310 | tree *false_lhs; | |
4311 | tree *false_rhs; | |
4312 | /* These are the codes to use for the left-hand side and right-hand | |
4313 | side of the COND_EXPR. Normally, they are the same as CODE. */ | |
4314 | enum tree_code lhs_code = code; | |
4315 | enum tree_code rhs_code = code; | |
4316 | /* And these are the types of the expressions. */ | |
4317 | tree lhs_type = type; | |
4318 | tree rhs_type = type; | |
4319 | ||
4320 | if (cond_first_p) | |
4321 | { | |
4322 | true_rhs = false_rhs = &arg; | |
4323 | true_lhs = &true_value; | |
4324 | false_lhs = &false_value; | |
4325 | } | |
4326 | else | |
4327 | { | |
4328 | true_lhs = false_lhs = &arg; | |
4329 | true_rhs = &true_value; | |
4330 | false_rhs = &false_value; | |
4331 | } | |
4332 | ||
4333 | if (TREE_CODE (cond) == COND_EXPR) | |
4334 | { | |
4335 | test = TREE_OPERAND (cond, 0); | |
4336 | true_value = TREE_OPERAND (cond, 1); | |
4337 | false_value = TREE_OPERAND (cond, 2); | |
4338 | /* If this operand throws an expression, then it does not make | |
4339 | sense to try to perform a logical or arithmetic operation | |
4340 | involving it. Instead of building `a + throw 3' for example, | |
4341 | we simply build `a, throw 3'. */ | |
4342 | if (VOID_TYPE_P (TREE_TYPE (true_value))) | |
4343 | { | |
4344 | lhs_code = COMPOUND_EXPR; | |
4345 | if (!cond_first_p) | |
4346 | lhs_type = void_type_node; | |
4347 | } | |
4348 | if (VOID_TYPE_P (TREE_TYPE (false_value))) | |
4349 | { | |
4350 | rhs_code = COMPOUND_EXPR; | |
4351 | if (!cond_first_p) | |
4352 | rhs_type = void_type_node; | |
4353 | } | |
4354 | } | |
4355 | else | |
4356 | { | |
4357 | tree testtype = TREE_TYPE (cond); | |
4358 | test = cond; | |
4359 | true_value = convert (testtype, integer_one_node); | |
4360 | false_value = convert (testtype, integer_zero_node); | |
4361 | } | |
dd3f0101 | 4362 | |
68626d4f MM |
4363 | /* If ARG is complex we want to make sure we only evaluate |
4364 | it once. Though this is only required if it is volatile, it | |
4365 | might be more efficient even if it is not. However, if we | |
4366 | succeed in folding one part to a constant, we do not need | |
4367 | to make this SAVE_EXPR. Since we do this optimization | |
4368 | primarily to see if we do end up with constant and this | |
4369 | SAVE_EXPR interferes with later optimizations, suppressing | |
4370 | it when we can is important. | |
dd3f0101 | 4371 | |
68626d4f MM |
4372 | If we are not in a function, we can't make a SAVE_EXPR, so don't |
4373 | try to do so. Don't try to see if the result is a constant | |
4374 | if an arm is a COND_EXPR since we get exponential behavior | |
4375 | in that case. */ | |
dd3f0101 | 4376 | |
68626d4f | 4377 | if (TREE_CODE (arg) != SAVE_EXPR && ! TREE_CONSTANT (arg) |
43577e6b | 4378 | && (*lang_hooks.decls.global_bindings_p) () == 0 |
68626d4f MM |
4379 | && ((TREE_CODE (arg) != VAR_DECL |
4380 | && TREE_CODE (arg) != PARM_DECL) | |
4381 | || TREE_SIDE_EFFECTS (arg))) | |
4382 | { | |
4383 | if (TREE_CODE (true_value) != COND_EXPR) | |
4384 | lhs = fold (build (lhs_code, lhs_type, *true_lhs, *true_rhs)); | |
dd3f0101 | 4385 | |
68626d4f MM |
4386 | if (TREE_CODE (false_value) != COND_EXPR) |
4387 | rhs = fold (build (rhs_code, rhs_type, *false_lhs, *false_rhs)); | |
dd3f0101 | 4388 | |
68626d4f MM |
4389 | if ((lhs == 0 || ! TREE_CONSTANT (lhs)) |
4390 | && (rhs == 0 || !TREE_CONSTANT (rhs))) | |
4391 | arg = save_expr (arg), lhs = rhs = 0; | |
4392 | } | |
dd3f0101 | 4393 | |
68626d4f MM |
4394 | if (lhs == 0) |
4395 | lhs = fold (build (lhs_code, lhs_type, *true_lhs, *true_rhs)); | |
4396 | if (rhs == 0) | |
4397 | rhs = fold (build (rhs_code, rhs_type, *false_lhs, *false_rhs)); | |
dd3f0101 | 4398 | |
68626d4f | 4399 | test = fold (build (COND_EXPR, type, test, lhs, rhs)); |
dd3f0101 | 4400 | |
68626d4f MM |
4401 | if (TREE_CODE (arg) == SAVE_EXPR) |
4402 | return build (COMPOUND_EXPR, type, | |
4403 | convert (void_type_node, arg), | |
4404 | strip_compound_expr (test, arg)); | |
4405 | else | |
4406 | return convert (type, test); | |
4407 | } | |
4408 | ||
ab87f8c8 | 4409 | \f |
71925bc0 RS |
4410 | /* Subroutine of fold() that checks for the addition of +/- 0.0. |
4411 | ||
4412 | If !NEGATE, return true if ADDEND is +/-0.0 and, for all X of type | |
4413 | TYPE, X + ADDEND is the same as X. If NEGATE, return true if X - | |
4414 | ADDEND is the same as X. | |
4415 | ||
4416 | X + 0 and X - 0 both give X when X is NaN, infinite, or non-zero | |
4417 | and finite. The problematic cases are when X is zero, and its mode | |
4418 | has signed zeros. In the case of rounding towards -infinity, | |
4419 | X - 0 is not the same as X because 0 - 0 is -0. In other rounding | |
4420 | modes, X + 0 is not the same as X because -0 + 0 is 0. */ | |
4421 | ||
4422 | static bool | |
4423 | fold_real_zero_addition_p (type, addend, negate) | |
4424 | tree type, addend; | |
4425 | int negate; | |
4426 | { | |
4427 | if (!real_zerop (addend)) | |
4428 | return false; | |
4429 | ||
4430 | /* Allow the fold if zeros aren't signed, or their sign isn't important. */ | |
4431 | if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))) | |
4432 | return true; | |
4433 | ||
4434 | /* Treat x + -0 as x - 0 and x - -0 as x + 0. */ | |
4435 | if (TREE_CODE (addend) == REAL_CST | |
4436 | && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (addend))) | |
4437 | negate = !negate; | |
4438 | ||
4439 | /* The mode has signed zeros, and we have to honor their sign. | |
4440 | In this situation, there is only one case we can return true for. | |
4441 | X - 0 is the same as X unless rounding towards -infinity is | |
4442 | supported. */ | |
4443 | return negate && !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)); | |
4444 | } | |
4445 | ||
4446 | ||
6d716ca8 RS |
4447 | /* Perform constant folding and related simplification of EXPR. |
4448 | The related simplifications include x*1 => x, x*0 => 0, etc., | |
4449 | and application of the associative law. | |
4450 | NOP_EXPR conversions may be removed freely (as long as we | |
4451 | are careful not to change the C type of the overall expression) | |
4452 | We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR, | |
4453 | but we can constant-fold them if they have constant operands. */ | |
4454 | ||
4455 | tree | |
b6cc0a72 | 4456 | fold (expr) |
6d716ca8 RS |
4457 | tree expr; |
4458 | { | |
b3694847 | 4459 | tree t = expr; |
6d716ca8 | 4460 | tree t1 = NULL_TREE; |
c05a9b68 | 4461 | tree tem; |
6d716ca8 | 4462 | tree type = TREE_TYPE (expr); |
b3694847 SS |
4463 | tree arg0 = NULL_TREE, arg1 = NULL_TREE; |
4464 | enum tree_code code = TREE_CODE (t); | |
4465 | int kind = TREE_CODE_CLASS (code); | |
c05a9b68 | 4466 | int invert; |
6d716ca8 RS |
4467 | /* WINS will be nonzero when the switch is done |
4468 | if all operands are constant. */ | |
6d716ca8 RS |
4469 | int wins = 1; |
4470 | ||
b6cc0a72 | 4471 | /* Don't try to process an RTL_EXPR since its operands aren't trees. |
5fd7f37d | 4472 | Likewise for a SAVE_EXPR that's already been evaluated. */ |
dea8be3e | 4473 | if (code == RTL_EXPR || (code == SAVE_EXPR && SAVE_EXPR_RTL (t) != 0)) |
ac27d589 RK |
4474 | return t; |
4475 | ||
1796dff4 RH |
4476 | /* Return right away if a constant. */ |
4477 | if (kind == 'c') | |
4478 | return t; | |
b6cc0a72 | 4479 | |
dbecbbe4 JL |
4480 | #ifdef MAX_INTEGER_COMPUTATION_MODE |
4481 | check_max_integer_computation_mode (expr); | |
4482 | #endif | |
4483 | ||
1b81aa14 RS |
4484 | if (code == NOP_EXPR || code == FLOAT_EXPR || code == CONVERT_EXPR) |
4485 | { | |
1cc1b11a RS |
4486 | tree subop; |
4487 | ||
1b81aa14 RS |
4488 | /* Special case for conversion ops that can have fixed point args. */ |
4489 | arg0 = TREE_OPERAND (t, 0); | |
4490 | ||
4491 | /* Don't use STRIP_NOPS, because signedness of argument type matters. */ | |
4492 | if (arg0 != 0) | |
14a774a9 | 4493 | STRIP_SIGN_NOPS (arg0); |
1b81aa14 | 4494 | |
1cc1b11a RS |
4495 | if (arg0 != 0 && TREE_CODE (arg0) == COMPLEX_CST) |
4496 | subop = TREE_REALPART (arg0); | |
4497 | else | |
4498 | subop = arg0; | |
4499 | ||
4500 | if (subop != 0 && TREE_CODE (subop) != INTEGER_CST | |
1cc1b11a | 4501 | && TREE_CODE (subop) != REAL_CST |
1b81aa14 RS |
4502 | ) |
4503 | /* Note that TREE_CONSTANT isn't enough: | |
4504 | static var addresses are constant but we can't | |
4505 | do arithmetic on them. */ | |
4506 | wins = 0; | |
4507 | } | |
efd58783 | 4508 | else if (IS_EXPR_CODE_CLASS (kind) || kind == 'r') |
6d716ca8 | 4509 | { |
b3694847 SS |
4510 | int len = first_rtl_op (code); |
4511 | int i; | |
6d716ca8 RS |
4512 | for (i = 0; i < len; i++) |
4513 | { | |
4514 | tree op = TREE_OPERAND (t, i); | |
1cc1b11a | 4515 | tree subop; |
6d716ca8 RS |
4516 | |
4517 | if (op == 0) | |
4518 | continue; /* Valid for CALL_EXPR, at least. */ | |
4519 | ||
b8a91430 RK |
4520 | if (kind == '<' || code == RSHIFT_EXPR) |
4521 | { | |
4522 | /* Signedness matters here. Perhaps we can refine this | |
4523 | later. */ | |
14a774a9 | 4524 | STRIP_SIGN_NOPS (op); |
b8a91430 RK |
4525 | } |
4526 | else | |
13eb1f7f RK |
4527 | /* Strip any conversions that don't change the mode. */ |
4528 | STRIP_NOPS (op); | |
b6cc0a72 | 4529 | |
1cc1b11a RS |
4530 | if (TREE_CODE (op) == COMPLEX_CST) |
4531 | subop = TREE_REALPART (op); | |
4532 | else | |
4533 | subop = op; | |
4534 | ||
4535 | if (TREE_CODE (subop) != INTEGER_CST | |
ba31d94e | 4536 | && TREE_CODE (subop) != REAL_CST) |
6d716ca8 RS |
4537 | /* Note that TREE_CONSTANT isn't enough: |
4538 | static var addresses are constant but we can't | |
4539 | do arithmetic on them. */ | |
4540 | wins = 0; | |
4541 | ||
4542 | if (i == 0) | |
4543 | arg0 = op; | |
4544 | else if (i == 1) | |
4545 | arg1 = op; | |
4546 | } | |
4547 | } | |
4548 | ||
4549 | /* If this is a commutative operation, and ARG0 is a constant, move it | |
4550 | to ARG1 to reduce the number of tests below. */ | |
4551 | if ((code == PLUS_EXPR || code == MULT_EXPR || code == MIN_EXPR | |
4552 | || code == MAX_EXPR || code == BIT_IOR_EXPR || code == BIT_XOR_EXPR | |
4553 | || code == BIT_AND_EXPR) | |
4554 | && (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)) | |
4555 | { | |
c05a9b68 | 4556 | tem = arg0; arg0 = arg1; arg1 = tem; |
6d716ca8 | 4557 | |
c05a9b68 RS |
4558 | tem = TREE_OPERAND (t, 0); TREE_OPERAND (t, 0) = TREE_OPERAND (t, 1); |
4559 | TREE_OPERAND (t, 1) = tem; | |
6d716ca8 RS |
4560 | } |
4561 | ||
4562 | /* Now WINS is set as described above, | |
4563 | ARG0 is the first operand of EXPR, | |
4564 | and ARG1 is the second operand (if it has more than one operand). | |
4565 | ||
4566 | First check for cases where an arithmetic operation is applied to a | |
4567 | compound, conditional, or comparison operation. Push the arithmetic | |
4568 | operation inside the compound or conditional to see if any folding | |
4569 | can then be done. Convert comparison to conditional for this purpose. | |
4570 | The also optimizes non-constant cases that used to be done in | |
96d4cf0a RK |
4571 | expand_expr. |
4572 | ||
fba5638f | 4573 | Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR, |
61f275ff RK |
4574 | one of the operands is a comparison and the other is a comparison, a |
4575 | BIT_AND_EXPR with the constant 1, or a truth value. In that case, the | |
4576 | code below would make the expression more complex. Change it to a | |
b6cc0a72 | 4577 | TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to |
2df46b06 | 4578 | TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */ |
96d4cf0a | 4579 | |
2df46b06 RK |
4580 | if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR |
4581 | || code == EQ_EXPR || code == NE_EXPR) | |
61f275ff RK |
4582 | && ((truth_value_p (TREE_CODE (arg0)) |
4583 | && (truth_value_p (TREE_CODE (arg1)) | |
96d4cf0a RK |
4584 | || (TREE_CODE (arg1) == BIT_AND_EXPR |
4585 | && integer_onep (TREE_OPERAND (arg1, 1))))) | |
61f275ff RK |
4586 | || (truth_value_p (TREE_CODE (arg1)) |
4587 | && (truth_value_p (TREE_CODE (arg0)) | |
96d4cf0a RK |
4588 | || (TREE_CODE (arg0) == BIT_AND_EXPR |
4589 | && integer_onep (TREE_OPERAND (arg0, 1))))))) | |
2df46b06 RK |
4590 | { |
4591 | t = fold (build (code == BIT_AND_EXPR ? TRUTH_AND_EXPR | |
4592 | : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR | |
4593 | : TRUTH_XOR_EXPR, | |
4594 | type, arg0, arg1)); | |
4595 | ||
4596 | if (code == EQ_EXPR) | |
4597 | t = invert_truthvalue (t); | |
4598 | ||
4599 | return t; | |
4600 | } | |
96d4cf0a | 4601 | |
6d716ca8 RS |
4602 | if (TREE_CODE_CLASS (code) == '1') |
4603 | { | |
4604 | if (TREE_CODE (arg0) == COMPOUND_EXPR) | |
4605 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
4606 | fold (build1 (code, type, TREE_OPERAND (arg0, 1)))); | |
4607 | else if (TREE_CODE (arg0) == COND_EXPR) | |
b8eb43a2 RK |
4608 | { |
4609 | t = fold (build (COND_EXPR, type, TREE_OPERAND (arg0, 0), | |
4610 | fold (build1 (code, type, TREE_OPERAND (arg0, 1))), | |
4611 | fold (build1 (code, type, TREE_OPERAND (arg0, 2))))); | |
4612 | ||
4613 | /* If this was a conversion, and all we did was to move into | |
e1f56f62 RK |
4614 | inside the COND_EXPR, bring it back out. But leave it if |
4615 | it is a conversion from integer to integer and the | |
4616 | result precision is no wider than a word since such a | |
4617 | conversion is cheap and may be optimized away by combine, | |
4618 | while it couldn't if it were outside the COND_EXPR. Then return | |
4619 | so we don't get into an infinite recursion loop taking the | |
4620 | conversion out and then back in. */ | |
b8eb43a2 RK |
4621 | |
4622 | if ((code == NOP_EXPR || code == CONVERT_EXPR | |
4623 | || code == NON_LVALUE_EXPR) | |
4624 | && TREE_CODE (t) == COND_EXPR | |
4625 | && TREE_CODE (TREE_OPERAND (t, 1)) == code | |
459a2653 RK |
4626 | && TREE_CODE (TREE_OPERAND (t, 2)) == code |
4627 | && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)) | |
e1f56f62 RK |
4628 | == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 2), 0))) |
4629 | && ! (INTEGRAL_TYPE_P (TREE_TYPE (t)) | |
d4b60170 RK |
4630 | && (INTEGRAL_TYPE_P |
4631 | (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)))) | |
e1f56f62 | 4632 | && TYPE_PRECISION (TREE_TYPE (t)) <= BITS_PER_WORD)) |
b8eb43a2 RK |
4633 | t = build1 (code, type, |
4634 | build (COND_EXPR, | |
d4b60170 RK |
4635 | TREE_TYPE (TREE_OPERAND |
4636 | (TREE_OPERAND (t, 1), 0)), | |
b8eb43a2 RK |
4637 | TREE_OPERAND (t, 0), |
4638 | TREE_OPERAND (TREE_OPERAND (t, 1), 0), | |
4639 | TREE_OPERAND (TREE_OPERAND (t, 2), 0))); | |
4640 | return t; | |
4641 | } | |
b6cc0a72 | 4642 | else if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<') |
6d716ca8 RS |
4643 | return fold (build (COND_EXPR, type, arg0, |
4644 | fold (build1 (code, type, integer_one_node)), | |
4645 | fold (build1 (code, type, integer_zero_node)))); | |
4646 | } | |
96d4cf0a RK |
4647 | else if (TREE_CODE_CLASS (code) == '2' |
4648 | || TREE_CODE_CLASS (code) == '<') | |
6d716ca8 RS |
4649 | { |
4650 | if (TREE_CODE (arg1) == COMPOUND_EXPR) | |
4651 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), | |
96d4cf0a RK |
4652 | fold (build (code, type, |
4653 | arg0, TREE_OPERAND (arg1, 1)))); | |
f0eebf28 RK |
4654 | else if ((TREE_CODE (arg1) == COND_EXPR |
4655 | || (TREE_CODE_CLASS (TREE_CODE (arg1)) == '<' | |
4656 | && TREE_CODE_CLASS (code) != '<')) | |
ab87f8c8 JL |
4657 | && (TREE_CODE (arg0) != COND_EXPR |
4658 | || count_cond (arg0, 25) + count_cond (arg1, 25) <= 25) | |
9ec36da5 | 4659 | && (! TREE_SIDE_EFFECTS (arg0) |
43577e6b | 4660 | || ((*lang_hooks.decls.global_bindings_p) () == 0 |
9ec36da5 | 4661 | && ! contains_placeholder_p (arg0)))) |
dd3f0101 | 4662 | return |
68626d4f MM |
4663 | fold_binary_op_with_conditional_arg (code, type, arg1, arg0, |
4664 | /*cond_first_p=*/0); | |
6d716ca8 RS |
4665 | else if (TREE_CODE (arg0) == COMPOUND_EXPR) |
4666 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
4667 | fold (build (code, type, TREE_OPERAND (arg0, 1), arg1))); | |
f0eebf28 RK |
4668 | else if ((TREE_CODE (arg0) == COND_EXPR |
4669 | || (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' | |
4670 | && TREE_CODE_CLASS (code) != '<')) | |
ab87f8c8 JL |
4671 | && (TREE_CODE (arg1) != COND_EXPR |
4672 | || count_cond (arg0, 25) + count_cond (arg1, 25) <= 25) | |
9ec36da5 | 4673 | && (! TREE_SIDE_EFFECTS (arg1) |
43577e6b | 4674 | || ((*lang_hooks.decls.global_bindings_p) () == 0 |
9ec36da5 | 4675 | && ! contains_placeholder_p (arg1)))) |
dd3f0101 | 4676 | return |
68626d4f MM |
4677 | fold_binary_op_with_conditional_arg (code, type, arg0, arg1, |
4678 | /*cond_first_p=*/1); | |
6d716ca8 | 4679 | } |
c05a9b68 RS |
4680 | else if (TREE_CODE_CLASS (code) == '<' |
4681 | && TREE_CODE (arg0) == COMPOUND_EXPR) | |
4682 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
4683 | fold (build (code, type, TREE_OPERAND (arg0, 1), arg1))); | |
4684 | else if (TREE_CODE_CLASS (code) == '<' | |
4685 | && TREE_CODE (arg1) == COMPOUND_EXPR) | |
4686 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), | |
4687 | fold (build (code, type, arg0, TREE_OPERAND (arg1, 1)))); | |
b6cc0a72 | 4688 | |
6d716ca8 RS |
4689 | switch (code) |
4690 | { | |
4691 | case INTEGER_CST: | |
4692 | case REAL_CST: | |
69ef87e2 | 4693 | case VECTOR_CST: |
6d716ca8 RS |
4694 | case STRING_CST: |
4695 | case COMPLEX_CST: | |
4696 | case CONSTRUCTOR: | |
4697 | return t; | |
4698 | ||
4699 | case CONST_DECL: | |
4700 | return fold (DECL_INITIAL (t)); | |
4701 | ||
4702 | case NOP_EXPR: | |
4703 | case FLOAT_EXPR: | |
4704 | case CONVERT_EXPR: | |
4705 | case FIX_TRUNC_EXPR: | |
4706 | /* Other kinds of FIX are not handled properly by fold_convert. */ | |
33558beb | 4707 | |
e1f56f62 RK |
4708 | if (TREE_TYPE (TREE_OPERAND (t, 0)) == TREE_TYPE (t)) |
4709 | return TREE_OPERAND (t, 0); | |
4710 | ||
7e139075 RK |
4711 | /* Handle cases of two conversions in a row. */ |
4712 | if (TREE_CODE (TREE_OPERAND (t, 0)) == NOP_EXPR | |
4713 | || TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR) | |
4714 | { | |
4715 | tree inside_type = TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
4716 | tree inter_type = TREE_TYPE (TREE_OPERAND (t, 0)); | |
4717 | tree final_type = TREE_TYPE (t); | |
4718 | int inside_int = INTEGRAL_TYPE_P (inside_type); | |
7f0b305c | 4719 | int inside_ptr = POINTER_TYPE_P (inside_type); |
7e139075 | 4720 | int inside_float = FLOAT_TYPE_P (inside_type); |
770ae6cc | 4721 | unsigned int inside_prec = TYPE_PRECISION (inside_type); |
7e139075 RK |
4722 | int inside_unsignedp = TREE_UNSIGNED (inside_type); |
4723 | int inter_int = INTEGRAL_TYPE_P (inter_type); | |
7f0b305c | 4724 | int inter_ptr = POINTER_TYPE_P (inter_type); |
7e139075 | 4725 | int inter_float = FLOAT_TYPE_P (inter_type); |
770ae6cc | 4726 | unsigned int inter_prec = TYPE_PRECISION (inter_type); |
7e139075 RK |
4727 | int inter_unsignedp = TREE_UNSIGNED (inter_type); |
4728 | int final_int = INTEGRAL_TYPE_P (final_type); | |
7f0b305c | 4729 | int final_ptr = POINTER_TYPE_P (final_type); |
7e139075 | 4730 | int final_float = FLOAT_TYPE_P (final_type); |
770ae6cc | 4731 | unsigned int final_prec = TYPE_PRECISION (final_type); |
7e139075 RK |
4732 | int final_unsignedp = TREE_UNSIGNED (final_type); |
4733 | ||
b6cc0a72 | 4734 | /* In addition to the cases of two conversions in a row |
7e139075 RK |
4735 | handled below, if we are converting something to its own |
4736 | type via an object of identical or wider precision, neither | |
4737 | conversion is needed. */ | |
30355eaa | 4738 | if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (final_type) |
7e139075 RK |
4739 | && ((inter_int && final_int) || (inter_float && final_float)) |
4740 | && inter_prec >= final_prec) | |
72bd1f9e | 4741 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
7e139075 RK |
4742 | |
4743 | /* Likewise, if the intermediate and final types are either both | |
4744 | float or both integer, we don't need the middle conversion if | |
4745 | it is wider than the final type and doesn't change the signedness | |
7f0b305c | 4746 | (for integers). Avoid this if the final type is a pointer |
410d3f5d RK |
4747 | since then we sometimes need the inner conversion. Likewise if |
4748 | the outer has a precision not equal to the size of its mode. */ | |
7e139075 RK |
4749 | if ((((inter_int || inter_ptr) && (inside_int || inside_ptr)) |
4750 | || (inter_float && inside_float)) | |
4751 | && inter_prec >= inside_prec | |
7f0b305c | 4752 | && (inter_float || inter_unsignedp == inside_unsignedp) |
410d3f5d RK |
4753 | && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type)) |
4754 | && TYPE_MODE (final_type) == TYPE_MODE (inter_type)) | |
7f0b305c | 4755 | && ! final_ptr) |
7e139075 RK |
4756 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
4757 | ||
ba3ad5e0 PDM |
4758 | /* If we have a sign-extension of a zero-extended value, we can |
4759 | replace that by a single zero-extension. */ | |
4760 | if (inside_int && inter_int && final_int | |
4761 | && inside_prec < inter_prec && inter_prec < final_prec | |
4762 | && inside_unsignedp && !inter_unsignedp) | |
4763 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
4764 | ||
7e139075 RK |
4765 | /* Two conversions in a row are not needed unless: |
4766 | - some conversion is floating-point (overstrict for now), or | |
4767 | - the intermediate type is narrower than both initial and | |
4768 | final, or | |
4769 | - the intermediate type and innermost type differ in signedness, | |
4770 | and the outermost type is wider than the intermediate, or | |
4771 | - the initial type is a pointer type and the precisions of the | |
4772 | intermediate and final types differ, or | |
b6cc0a72 | 4773 | - the final type is a pointer type and the precisions of the |
7e139075 RK |
4774 | initial and intermediate types differ. */ |
4775 | if (! inside_float && ! inter_float && ! final_float | |
4776 | && (inter_prec > inside_prec || inter_prec > final_prec) | |
4777 | && ! (inside_int && inter_int | |
4778 | && inter_unsignedp != inside_unsignedp | |
4779 | && inter_prec < final_prec) | |
4780 | && ((inter_unsignedp && inter_prec > inside_prec) | |
4781 | == (final_unsignedp && final_prec > inter_prec)) | |
4782 | && ! (inside_ptr && inter_prec != final_prec) | |
410d3f5d RK |
4783 | && ! (final_ptr && inside_prec != inter_prec) |
4784 | && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type)) | |
4785 | && TYPE_MODE (final_type) == TYPE_MODE (inter_type)) | |
4786 | && ! final_ptr) | |
7e139075 RK |
4787 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
4788 | } | |
6d716ca8 RS |
4789 | |
4790 | if (TREE_CODE (TREE_OPERAND (t, 0)) == MODIFY_EXPR | |
d8f6dbb9 RS |
4791 | && TREE_CONSTANT (TREE_OPERAND (TREE_OPERAND (t, 0), 1)) |
4792 | /* Detect assigning a bitfield. */ | |
4793 | && !(TREE_CODE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)) == COMPONENT_REF | |
4794 | && DECL_BIT_FIELD (TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (t, 0), 0), 1)))) | |
6d716ca8 | 4795 | { |
d8f6dbb9 | 4796 | /* Don't leave an assignment inside a conversion |
f72aed24 | 4797 | unless assigning a bitfield. */ |
6d716ca8 RS |
4798 | tree prev = TREE_OPERAND (t, 0); |
4799 | TREE_OPERAND (t, 0) = TREE_OPERAND (prev, 1); | |
4800 | /* First do the assignment, then return converted constant. */ | |
4801 | t = build (COMPOUND_EXPR, TREE_TYPE (t), prev, fold (t)); | |
4802 | TREE_USED (t) = 1; | |
4803 | return t; | |
4804 | } | |
58c2956c RS |
4805 | |
4806 | /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer | |
4807 | constants (if x has signed type, the sign bit cannot be set | |
4808 | in c). This folds extension into the BIT_AND_EXPR. */ | |
4809 | if (INTEGRAL_TYPE_P (TREE_TYPE (t)) | |
57f851a3 | 4810 | && TREE_CODE (TREE_TYPE (t)) != BOOLEAN_TYPE |
58c2956c RS |
4811 | && TREE_CODE (TREE_OPERAND (t, 0)) == BIT_AND_EXPR |
4812 | && TREE_CODE (TREE_OPERAND (TREE_OPERAND (t, 0), 1)) == INTEGER_CST) | |
4813 | { | |
4814 | tree and = TREE_OPERAND (t, 0); | |
4815 | tree and0 = TREE_OPERAND (and, 0), and1 = TREE_OPERAND (and, 1); | |
4816 | int change = 0; | |
4817 | ||
4818 | if (TREE_UNSIGNED (TREE_TYPE (and)) | |
4819 | || (TYPE_PRECISION (TREE_TYPE (t)) | |
4820 | <= TYPE_PRECISION (TREE_TYPE (and)))) | |
4821 | change = 1; | |
4822 | else if (TYPE_PRECISION (TREE_TYPE (and1)) | |
4823 | <= HOST_BITS_PER_WIDE_INT | |
4824 | && host_integerp (and1, 1)) | |
4825 | { | |
4826 | unsigned HOST_WIDE_INT cst; | |
4827 | ||
4828 | cst = tree_low_cst (and1, 1); | |
4829 | cst &= (HOST_WIDE_INT) -1 | |
4830 | << (TYPE_PRECISION (TREE_TYPE (and1)) - 1); | |
4831 | change = (cst == 0); | |
4832 | #ifdef LOAD_EXTEND_OP | |
4833 | if (change | |
4834 | && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0))) | |
4835 | == ZERO_EXTEND)) | |
4836 | { | |
a32db605 | 4837 | tree uns = (*lang_hooks.types.unsigned_type) (TREE_TYPE (and0)); |
58c2956c RS |
4838 | and0 = convert (uns, and0); |
4839 | and1 = convert (uns, and1); | |
4840 | } | |
4841 | #endif | |
4842 | } | |
4843 | if (change) | |
4844 | return fold (build (BIT_AND_EXPR, TREE_TYPE (t), | |
4845 | convert (TREE_TYPE (t), and0), | |
4846 | convert (TREE_TYPE (t), and1))); | |
4847 | } | |
4848 | ||
6d716ca8 RS |
4849 | if (!wins) |
4850 | { | |
4851 | TREE_CONSTANT (t) = TREE_CONSTANT (arg0); | |
4852 | return t; | |
4853 | } | |
4854 | return fold_convert (t, arg0); | |
4855 | ||
ed239f5a RK |
4856 | case VIEW_CONVERT_EXPR: |
4857 | if (TREE_CODE (TREE_OPERAND (t, 0)) == VIEW_CONVERT_EXPR) | |
4858 | return build1 (VIEW_CONVERT_EXPR, type, | |
4859 | TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
4860 | return t; | |
4861 | ||
e082358b JM |
4862 | case COMPONENT_REF: |
4863 | if (TREE_CODE (arg0) == CONSTRUCTOR) | |
3ac4f0e6 JM |
4864 | { |
4865 | tree m = purpose_member (arg1, CONSTRUCTOR_ELTS (arg0)); | |
4866 | if (m) | |
4867 | t = TREE_VALUE (m); | |
4868 | } | |
e082358b JM |
4869 | return t; |
4870 | ||
6d716ca8 RS |
4871 | case RANGE_EXPR: |
4872 | TREE_CONSTANT (t) = wins; | |
4873 | return t; | |
4874 | ||
4875 | case NEGATE_EXPR: | |
4876 | if (wins) | |
4877 | { | |
4878 | if (TREE_CODE (arg0) == INTEGER_CST) | |
4879 | { | |
f9e158c3 JM |
4880 | unsigned HOST_WIDE_INT low; |
4881 | HOST_WIDE_INT high; | |
fe3e8e40 RS |
4882 | int overflow = neg_double (TREE_INT_CST_LOW (arg0), |
4883 | TREE_INT_CST_HIGH (arg0), | |
4884 | &low, &high); | |
4885 | t = build_int_2 (low, high); | |
6d716ca8 | 4886 | TREE_TYPE (t) = type; |
dc3907c5 PE |
4887 | TREE_OVERFLOW (t) |
4888 | = (TREE_OVERFLOW (arg0) | |
0c9cabe7 | 4889 | | force_fit_type (t, overflow && !TREE_UNSIGNED (type))); |
dc3907c5 PE |
4890 | TREE_CONSTANT_OVERFLOW (t) |
4891 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0); | |
6d716ca8 RS |
4892 | } |
4893 | else if (TREE_CODE (arg0) == REAL_CST) | |
4894 | t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0))); | |
6d716ca8 RS |
4895 | } |
4896 | else if (TREE_CODE (arg0) == NEGATE_EXPR) | |
4897 | return TREE_OPERAND (arg0, 0); | |
4898 | ||
4899 | /* Convert - (a - b) to (b - a) for non-floating-point. */ | |
1baa375f | 4900 | else if (TREE_CODE (arg0) == MINUS_EXPR |
de6c5979 | 4901 | && (! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations)) |
6d716ca8 RS |
4902 | return build (MINUS_EXPR, type, TREE_OPERAND (arg0, 1), |
4903 | TREE_OPERAND (arg0, 0)); | |
4904 | ||
4905 | return t; | |
4906 | ||
4907 | case ABS_EXPR: | |
4908 | if (wins) | |
4909 | { | |
4910 | if (TREE_CODE (arg0) == INTEGER_CST) | |
4911 | { | |
68e568c2 MM |
4912 | /* If the value is unsigned, then the absolute value is |
4913 | the same as the ordinary value. */ | |
4914 | if (TREE_UNSIGNED (type)) | |
4915 | return arg0; | |
4916 | /* Similarly, if the value is non-negative. */ | |
4917 | else if (INT_CST_LT (integer_minus_one_node, arg0)) | |
4918 | return arg0; | |
4919 | /* If the value is negative, then the absolute value is | |
4920 | its negation. */ | |
4921 | else | |
6d716ca8 | 4922 | { |
f9e158c3 JM |
4923 | unsigned HOST_WIDE_INT low; |
4924 | HOST_WIDE_INT high; | |
2a23183e RS |
4925 | int overflow = neg_double (TREE_INT_CST_LOW (arg0), |
4926 | TREE_INT_CST_HIGH (arg0), | |
4927 | &low, &high); | |
4928 | t = build_int_2 (low, high); | |
4929 | TREE_TYPE (t) = type; | |
dc3907c5 PE |
4930 | TREE_OVERFLOW (t) |
4931 | = (TREE_OVERFLOW (arg0) | |
e0f776fb | 4932 | | force_fit_type (t, overflow)); |
dc3907c5 PE |
4933 | TREE_CONSTANT_OVERFLOW (t) |
4934 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0); | |
6d716ca8 RS |
4935 | } |
4936 | } | |
4937 | else if (TREE_CODE (arg0) == REAL_CST) | |
4938 | { | |
c05a9b68 | 4939 | if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0))) |
6d716ca8 RS |
4940 | t = build_real (type, |
4941 | REAL_VALUE_NEGATE (TREE_REAL_CST (arg0))); | |
4942 | } | |
6d716ca8 RS |
4943 | } |
4944 | else if (TREE_CODE (arg0) == ABS_EXPR || TREE_CODE (arg0) == NEGATE_EXPR) | |
4945 | return build1 (ABS_EXPR, type, TREE_OPERAND (arg0, 0)); | |
4946 | return t; | |
4947 | ||
551064b1 RS |
4948 | case CONJ_EXPR: |
4949 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) | |
13eb1f7f | 4950 | return convert (type, arg0); |
551064b1 | 4951 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) |
c9869b75 | 4952 | return build (COMPLEX_EXPR, type, |
551064b1 | 4953 | TREE_OPERAND (arg0, 0), |
1baa375f | 4954 | negate_expr (TREE_OPERAND (arg0, 1))); |
551064b1 | 4955 | else if (TREE_CODE (arg0) == COMPLEX_CST) |
32812a40 JM |
4956 | return build_complex (type, TREE_REALPART (arg0), |
4957 | negate_expr (TREE_IMAGPART (arg0))); | |
551064b1 RS |
4958 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) |
4959 | return fold (build (TREE_CODE (arg0), type, | |
4960 | fold (build1 (CONJ_EXPR, type, | |
4961 | TREE_OPERAND (arg0, 0))), | |
4962 | fold (build1 (CONJ_EXPR, | |
4963 | type, TREE_OPERAND (arg0, 1))))); | |
4964 | else if (TREE_CODE (arg0) == CONJ_EXPR) | |
4965 | return TREE_OPERAND (arg0, 0); | |
4966 | return t; | |
4967 | ||
6d716ca8 RS |
4968 | case BIT_NOT_EXPR: |
4969 | if (wins) | |
4970 | { | |
380ff34a RK |
4971 | t = build_int_2 (~ TREE_INT_CST_LOW (arg0), |
4972 | ~ TREE_INT_CST_HIGH (arg0)); | |
6d716ca8 | 4973 | TREE_TYPE (t) = type; |
e0f776fb | 4974 | force_fit_type (t, 0); |
dc3907c5 | 4975 | TREE_OVERFLOW (t) = TREE_OVERFLOW (arg0); |
fe3e8e40 | 4976 | TREE_CONSTANT_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (arg0); |
6d716ca8 RS |
4977 | } |
4978 | else if (TREE_CODE (arg0) == BIT_NOT_EXPR) | |
4979 | return TREE_OPERAND (arg0, 0); | |
4980 | return t; | |
4981 | ||
4982 | case PLUS_EXPR: | |
4983 | /* A + (-B) -> A - B */ | |
4984 | if (TREE_CODE (arg1) == NEGATE_EXPR) | |
4985 | return fold (build (MINUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0))); | |
10414089 JL |
4986 | /* (-A) + B -> B - A */ |
4987 | if (TREE_CODE (arg0) == NEGATE_EXPR) | |
4988 | return fold (build (MINUS_EXPR, type, arg1, TREE_OPERAND (arg0, 0))); | |
7178e3af | 4989 | else if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
4990 | { |
4991 | if (integer_zerop (arg1)) | |
4992 | return non_lvalue (convert (type, arg0)); | |
4993 | ||
4994 | /* If we are adding two BIT_AND_EXPR's, both of which are and'ing | |
4995 | with a constant, and the two constants have no bits in common, | |
4996 | we should treat this as a BIT_IOR_EXPR since this may produce more | |
4997 | simplifications. */ | |
4998 | if (TREE_CODE (arg0) == BIT_AND_EXPR | |
4999 | && TREE_CODE (arg1) == BIT_AND_EXPR | |
5000 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
5001 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST | |
5002 | && integer_zerop (const_binop (BIT_AND_EXPR, | |
5003 | TREE_OPERAND (arg0, 1), | |
91d33e36 | 5004 | TREE_OPERAND (arg1, 1), 0))) |
6d716ca8 RS |
5005 | { |
5006 | code = BIT_IOR_EXPR; | |
5007 | goto bit_ior; | |
5008 | } | |
6a96fcb4 | 5009 | |
abe4f192 | 5010 | /* Reassociate (plus (plus (mult) (foo)) (mult)) as |
b6cc0a72 | 5011 | (plus (plus (mult) (mult)) (foo)) so that we can |
abe4f192 RH |
5012 | take advantage of the factoring cases below. */ |
5013 | if ((TREE_CODE (arg0) == PLUS_EXPR | |
5014 | && TREE_CODE (arg1) == MULT_EXPR) | |
5015 | || (TREE_CODE (arg1) == PLUS_EXPR | |
b6cc0a72 | 5016 | && TREE_CODE (arg0) == MULT_EXPR)) |
abe4f192 RH |
5017 | { |
5018 | tree parg0, parg1, parg, marg; | |
5019 | ||
5020 | if (TREE_CODE (arg0) == PLUS_EXPR) | |
5021 | parg = arg0, marg = arg1; | |
5022 | else | |
5023 | parg = arg1, marg = arg0; | |
5024 | parg0 = TREE_OPERAND (parg, 0); | |
5025 | parg1 = TREE_OPERAND (parg, 1); | |
5026 | STRIP_NOPS (parg0); | |
5027 | STRIP_NOPS (parg1); | |
5028 | ||
5029 | if (TREE_CODE (parg0) == MULT_EXPR | |
5030 | && TREE_CODE (parg1) != MULT_EXPR) | |
5031 | return fold (build (PLUS_EXPR, type, | |
5032 | fold (build (PLUS_EXPR, type, parg0, marg)), | |
5033 | parg1)); | |
5034 | if (TREE_CODE (parg0) != MULT_EXPR | |
5035 | && TREE_CODE (parg1) == MULT_EXPR) | |
5036 | return fold (build (PLUS_EXPR, type, | |
5037 | fold (build (PLUS_EXPR, type, parg1, marg)), | |
5038 | parg0)); | |
5039 | } | |
5040 | ||
45f97e2e RH |
5041 | if (TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (arg1) == MULT_EXPR) |
5042 | { | |
5043 | tree arg00, arg01, arg10, arg11; | |
07444f1d | 5044 | tree alt0 = NULL_TREE, alt1 = NULL_TREE, same; |
45f97e2e RH |
5045 | |
5046 | /* (A * C) + (B * C) -> (A+B) * C. | |
5047 | We are most concerned about the case where C is a constant, | |
5048 | but other combinations show up during loop reduction. Since | |
5049 | it is not difficult, try all four possibilities. */ | |
5050 | ||
5051 | arg00 = TREE_OPERAND (arg0, 0); | |
5052 | arg01 = TREE_OPERAND (arg0, 1); | |
5053 | arg10 = TREE_OPERAND (arg1, 0); | |
5054 | arg11 = TREE_OPERAND (arg1, 1); | |
5055 | same = NULL_TREE; | |
5056 | ||
5057 | if (operand_equal_p (arg01, arg11, 0)) | |
5058 | same = arg01, alt0 = arg00, alt1 = arg10; | |
5059 | else if (operand_equal_p (arg00, arg10, 0)) | |
5060 | same = arg00, alt0 = arg01, alt1 = arg11; | |
5061 | else if (operand_equal_p (arg00, arg11, 0)) | |
5062 | same = arg00, alt0 = arg01, alt1 = arg10; | |
5063 | else if (operand_equal_p (arg01, arg10, 0)) | |
5064 | same = arg01, alt0 = arg00, alt1 = arg11; | |
5065 | ||
abe4f192 RH |
5066 | /* No identical multiplicands; see if we can find a common |
5067 | power-of-two factor in non-power-of-two multiplies. This | |
5068 | can help in multi-dimensional array access. */ | |
5069 | else if (TREE_CODE (arg01) == INTEGER_CST | |
5070 | && TREE_CODE (arg11) == INTEGER_CST | |
5071 | && TREE_INT_CST_HIGH (arg01) == 0 | |
5072 | && TREE_INT_CST_HIGH (arg11) == 0) | |
5073 | { | |
5074 | HOST_WIDE_INT int01, int11, tmp; | |
5075 | int01 = TREE_INT_CST_LOW (arg01); | |
5076 | int11 = TREE_INT_CST_LOW (arg11); | |
5077 | ||
5078 | /* Move min of absolute values to int11. */ | |
5079 | if ((int01 >= 0 ? int01 : -int01) | |
5080 | < (int11 >= 0 ? int11 : -int11)) | |
5081 | { | |
5082 | tmp = int01, int01 = int11, int11 = tmp; | |
5083 | alt0 = arg00, arg00 = arg10, arg10 = alt0; | |
5084 | alt0 = arg01, arg01 = arg11, arg11 = alt0; | |
5085 | } | |
5086 | ||
5087 | if (exact_log2 (int11) > 0 && int01 % int11 == 0) | |
5088 | { | |
5089 | alt0 = fold (build (MULT_EXPR, type, arg00, | |
5090 | build_int_2 (int01 / int11, 0))); | |
5091 | alt1 = arg10; | |
5092 | same = arg11; | |
5093 | } | |
5094 | } | |
5095 | ||
45f97e2e | 5096 | if (same) |
b6cc0a72 | 5097 | return fold (build (MULT_EXPR, type, |
45f97e2e RH |
5098 | fold (build (PLUS_EXPR, type, alt0, alt1)), |
5099 | same)); | |
5100 | } | |
6d716ca8 | 5101 | } |
71925bc0 RS |
5102 | |
5103 | /* See if ARG1 is zero and X + ARG1 reduces to X. */ | |
5104 | else if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 0)) | |
10414089 JL |
5105 | return non_lvalue (convert (type, arg0)); |
5106 | ||
71925bc0 RS |
5107 | /* Likewise if the operands are reversed. */ |
5108 | else if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0)) | |
5109 | return non_lvalue (convert (type, arg1)); | |
5110 | ||
79e8185c JH |
5111 | bit_rotate: |
5112 | /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A | |
5113 | is a rotate of A by C1 bits. */ | |
5114 | /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A | |
5115 | is a rotate of A by B bits. */ | |
5116 | { | |
b3694847 | 5117 | enum tree_code code0, code1; |
b6cc0a72 KH |
5118 | code0 = TREE_CODE (arg0); |
5119 | code1 = TREE_CODE (arg1); | |
5120 | if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR) | |
5121 | || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR)) | |
79e8185c | 5122 | && operand_equal_p (TREE_OPERAND (arg0, 0), |
b6cc0a72 | 5123 | TREE_OPERAND (arg1, 0), 0) |
79e8185c JH |
5124 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))) |
5125 | { | |
b3694847 SS |
5126 | tree tree01, tree11; |
5127 | enum tree_code code01, code11; | |
79e8185c JH |
5128 | |
5129 | tree01 = TREE_OPERAND (arg0, 1); | |
5130 | tree11 = TREE_OPERAND (arg1, 1); | |
5131 | STRIP_NOPS (tree01); | |
5132 | STRIP_NOPS (tree11); | |
5133 | code01 = TREE_CODE (tree01); | |
5134 | code11 = TREE_CODE (tree11); | |
5135 | if (code01 == INTEGER_CST | |
b6cc0a72 KH |
5136 | && code11 == INTEGER_CST |
5137 | && TREE_INT_CST_HIGH (tree01) == 0 | |
5138 | && TREE_INT_CST_HIGH (tree11) == 0 | |
5139 | && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11)) | |
5140 | == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))))) | |
79e8185c | 5141 | return build (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0), |
b6cc0a72 | 5142 | code0 == LSHIFT_EXPR ? tree01 : tree11); |
79e8185c JH |
5143 | else if (code11 == MINUS_EXPR) |
5144 | { | |
b6cc0a72 KH |
5145 | tree tree110, tree111; |
5146 | tree110 = TREE_OPERAND (tree11, 0); | |
5147 | tree111 = TREE_OPERAND (tree11, 1); | |
5148 | STRIP_NOPS (tree110); | |
5149 | STRIP_NOPS (tree111); | |
5150 | if (TREE_CODE (tree110) == INTEGER_CST | |
05bccae2 RK |
5151 | && 0 == compare_tree_int (tree110, |
5152 | TYPE_PRECISION | |
5153 | (TREE_TYPE (TREE_OPERAND | |
5154 | (arg0, 0)))) | |
79e8185c | 5155 | && operand_equal_p (tree01, tree111, 0)) |
b6cc0a72 KH |
5156 | return build ((code0 == LSHIFT_EXPR |
5157 | ? LROTATE_EXPR | |
5158 | : RROTATE_EXPR), | |
5159 | type, TREE_OPERAND (arg0, 0), tree01); | |
79e8185c JH |
5160 | } |
5161 | else if (code01 == MINUS_EXPR) | |
5162 | { | |
b6cc0a72 KH |
5163 | tree tree010, tree011; |
5164 | tree010 = TREE_OPERAND (tree01, 0); | |
5165 | tree011 = TREE_OPERAND (tree01, 1); | |
5166 | STRIP_NOPS (tree010); | |
5167 | STRIP_NOPS (tree011); | |
5168 | if (TREE_CODE (tree010) == INTEGER_CST | |
05bccae2 RK |
5169 | && 0 == compare_tree_int (tree010, |
5170 | TYPE_PRECISION | |
5171 | (TREE_TYPE (TREE_OPERAND | |
5172 | (arg0, 0)))) | |
79e8185c | 5173 | && operand_equal_p (tree11, tree011, 0)) |
b6cc0a72 KH |
5174 | return build ((code0 != LSHIFT_EXPR |
5175 | ? LROTATE_EXPR | |
5176 | : RROTATE_EXPR), | |
5177 | type, TREE_OPERAND (arg0, 0), tree11); | |
79e8185c JH |
5178 | } |
5179 | } | |
5180 | } | |
10414089 | 5181 | |
6d716ca8 | 5182 | associate: |
1baa375f RK |
5183 | /* In most languages, can't associate operations on floats through |
5184 | parentheses. Rather than remember where the parentheses were, we | |
5185 | don't associate floats at all. It shouldn't matter much. However, | |
5186 | associating multiplications is only very slightly inaccurate, so do | |
de6c5979 | 5187 | that if -funsafe-math-optimizations is specified. */ |
1baa375f RK |
5188 | |
5189 | if (! wins | |
5190 | && (! FLOAT_TYPE_P (type) | |
de6c5979 | 5191 | || (flag_unsafe_math_optimizations && code == MULT_EXPR))) |
6d716ca8 | 5192 | { |
cff27795 EB |
5193 | tree var0, con0, lit0, minus_lit0; |
5194 | tree var1, con1, lit1, minus_lit1; | |
1baa375f RK |
5195 | |
5196 | /* Split both trees into variables, constants, and literals. Then | |
5197 | associate each group together, the constants with literals, | |
5198 | then the result with variables. This increases the chances of | |
5199 | literals being recombined later and of generating relocatable | |
30f7a378 | 5200 | expressions for the sum of a constant and literal. */ |
cff27795 EB |
5201 | var0 = split_tree (arg0, code, &con0, &lit0, &minus_lit0, 0); |
5202 | var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1, | |
5203 | code == MINUS_EXPR); | |
1baa375f RK |
5204 | |
5205 | /* Only do something if we found more than two objects. Otherwise, | |
5206 | nothing has changed and we risk infinite recursion. */ | |
cff27795 EB |
5207 | if (2 < ((var0 != 0) + (var1 != 0) |
5208 | + (con0 != 0) + (con1 != 0) | |
5209 | + (lit0 != 0) + (lit1 != 0) | |
5210 | + (minus_lit0 != 0) + (minus_lit1 != 0))) | |
6d716ca8 | 5211 | { |
cff27795 EB |
5212 | /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */ |
5213 | if (code == MINUS_EXPR) | |
5214 | code = PLUS_EXPR; | |
5215 | ||
1baa375f RK |
5216 | var0 = associate_trees (var0, var1, code, type); |
5217 | con0 = associate_trees (con0, con1, code, type); | |
5218 | lit0 = associate_trees (lit0, lit1, code, type); | |
cff27795 EB |
5219 | minus_lit0 = associate_trees (minus_lit0, minus_lit1, code, type); |
5220 | ||
5221 | /* Preserve the MINUS_EXPR if the negative part of the literal is | |
5222 | greater than the positive part. Otherwise, the multiplicative | |
5223 | folding code (i.e extract_muldiv) may be fooled in case | |
5224 | unsigned constants are substracted, like in the following | |
5225 | example: ((X*2 + 4) - 8U)/2. */ | |
5226 | if (minus_lit0 && lit0) | |
5227 | { | |
5228 | if (tree_int_cst_lt (lit0, minus_lit0)) | |
5229 | { | |
5230 | minus_lit0 = associate_trees (minus_lit0, lit0, | |
5231 | MINUS_EXPR, type); | |
5232 | lit0 = 0; | |
5233 | } | |
5234 | else | |
5235 | { | |
5236 | lit0 = associate_trees (lit0, minus_lit0, | |
5237 | MINUS_EXPR, type); | |
5238 | minus_lit0 = 0; | |
5239 | } | |
5240 | } | |
5241 | if (minus_lit0) | |
5242 | { | |
5243 | if (con0 == 0) | |
5244 | return convert (type, associate_trees (var0, minus_lit0, | |
5245 | MINUS_EXPR, type)); | |
5246 | else | |
5247 | { | |
5248 | con0 = associate_trees (con0, minus_lit0, | |
5249 | MINUS_EXPR, type); | |
5250 | return convert (type, associate_trees (var0, con0, | |
5251 | PLUS_EXPR, type)); | |
5252 | } | |
5253 | } | |
5254 | ||
1baa375f RK |
5255 | con0 = associate_trees (con0, lit0, code, type); |
5256 | return convert (type, associate_trees (var0, con0, code, type)); | |
6d716ca8 RS |
5257 | } |
5258 | } | |
1baa375f | 5259 | |
6d716ca8 | 5260 | binary: |
6d716ca8 | 5261 | if (wins) |
91d33e36 | 5262 | t1 = const_binop (code, arg0, arg1, 0); |
6d716ca8 RS |
5263 | if (t1 != NULL_TREE) |
5264 | { | |
5265 | /* The return value should always have | |
5266 | the same type as the original expression. */ | |
380ff34a RK |
5267 | if (TREE_TYPE (t1) != TREE_TYPE (t)) |
5268 | t1 = convert (TREE_TYPE (t), t1); | |
5269 | ||
6d716ca8 RS |
5270 | return t1; |
5271 | } | |
5272 | return t; | |
5273 | ||
5274 | case MINUS_EXPR: | |
10414089 JL |
5275 | /* A - (-B) -> A + B */ |
5276 | if (TREE_CODE (arg1) == NEGATE_EXPR) | |
5277 | return fold (build (PLUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0))); | |
5278 | /* (-A) - CST -> (-CST) - A for floating point (what about ints ?) */ | |
5279 | if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == REAL_CST) | |
5280 | return | |
b6cc0a72 | 5281 | fold (build (MINUS_EXPR, type, |
10414089 JL |
5282 | build_real (TREE_TYPE (arg1), |
5283 | REAL_VALUE_NEGATE (TREE_REAL_CST (arg1))), | |
5284 | TREE_OPERAND (arg0, 0))); | |
5285 | ||
7178e3af | 5286 | if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
5287 | { |
5288 | if (! wins && integer_zerop (arg0)) | |
b8fbe62c | 5289 | return negate_expr (convert (type, arg1)); |
6d716ca8 RS |
5290 | if (integer_zerop (arg1)) |
5291 | return non_lvalue (convert (type, arg0)); | |
6a96fcb4 RK |
5292 | |
5293 | /* (A * C) - (B * C) -> (A-B) * C. Since we are most concerned | |
5294 | about the case where C is a constant, just try one of the | |
5295 | four possibilities. */ | |
5296 | ||
5297 | if (TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (arg1) == MULT_EXPR | |
5298 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
5299 | TREE_OPERAND (arg1, 1), 0)) | |
5300 | return fold (build (MULT_EXPR, type, | |
5301 | fold (build (MINUS_EXPR, type, | |
5302 | TREE_OPERAND (arg0, 0), | |
5303 | TREE_OPERAND (arg1, 0))), | |
5304 | TREE_OPERAND (arg0, 1))); | |
6d716ca8 | 5305 | } |
fab446b8 | 5306 | |
71925bc0 RS |
5307 | /* See if ARG1 is zero and X - ARG1 reduces to X. */ |
5308 | else if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 1)) | |
5309 | return non_lvalue (convert (type, arg0)); | |
5310 | ||
5311 | /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether | |
5312 | ARG0 is zero and X + ARG0 reduces to X, since that would mean | |
5313 | (-ARG1 + ARG0) reduces to -ARG1. */ | |
5314 | else if (!wins && fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0)) | |
5315 | return negate_expr (convert (type, arg1)); | |
a6acbe15 | 5316 | |
b6cc0a72 | 5317 | /* Fold &x - &x. This can happen from &x.foo - &x. |
fab446b8 RK |
5318 | This is unsafe for certain floats even in non-IEEE formats. |
5319 | In IEEE, it is unsafe because it does wrong for NaNs. | |
5320 | Also note that operand_equal_p is always false if an operand | |
5321 | is volatile. */ | |
5322 | ||
de6c5979 | 5323 | if ((! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations) |
59d90212 | 5324 | && operand_equal_p (arg0, arg1, 0)) |
fab446b8 | 5325 | return convert (type, integer_zero_node); |
a6acbe15 | 5326 | |
6d716ca8 RS |
5327 | goto associate; |
5328 | ||
5329 | case MULT_EXPR: | |
10414089 JL |
5330 | /* (-A) * (-B) -> A * B */ |
5331 | if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == NEGATE_EXPR) | |
5332 | return fold (build (MULT_EXPR, type, TREE_OPERAND (arg0, 0), | |
b6cc0a72 | 5333 | TREE_OPERAND (arg1, 0))); |
10414089 | 5334 | |
7178e3af | 5335 | if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
5336 | { |
5337 | if (integer_zerop (arg1)) | |
5338 | return omit_one_operand (type, arg1, arg0); | |
5339 | if (integer_onep (arg1)) | |
5340 | return non_lvalue (convert (type, arg0)); | |
5341 | ||
5342 | /* (a * (1 << b)) is (a << b) */ | |
5343 | if (TREE_CODE (arg1) == LSHIFT_EXPR | |
5344 | && integer_onep (TREE_OPERAND (arg1, 0))) | |
5345 | return fold (build (LSHIFT_EXPR, type, arg0, | |
5346 | TREE_OPERAND (arg1, 1))); | |
5347 | if (TREE_CODE (arg0) == LSHIFT_EXPR | |
5348 | && integer_onep (TREE_OPERAND (arg0, 0))) | |
5349 | return fold (build (LSHIFT_EXPR, type, arg1, | |
5350 | TREE_OPERAND (arg0, 1))); | |
1baa375f RK |
5351 | |
5352 | if (TREE_CODE (arg1) == INTEGER_CST | |
5353 | && 0 != (tem = extract_muldiv (TREE_OPERAND (t, 0), arg1, | |
5354 | code, NULL_TREE))) | |
5355 | return convert (type, tem); | |
5356 | ||
6d716ca8 | 5357 | } |
6d716ca8 RS |
5358 | else |
5359 | { | |
71925bc0 RS |
5360 | /* Maybe fold x * 0 to 0. The expressions aren't the same |
5361 | when x is NaN, since x * 0 is also NaN. Nor are they the | |
5362 | same in modes with signed zeros, since multiplying a | |
5363 | negative value by 0 gives -0, not +0. */ | |
5364 | if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))) | |
5365 | && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0))) | |
6d716ca8 RS |
5366 | && real_zerop (arg1)) |
5367 | return omit_one_operand (type, arg1, arg0); | |
c05a9b68 | 5368 | /* In IEEE floating point, x*1 is not equivalent to x for snans. |
6d716ca8 RS |
5369 | However, ANSI says we can drop signals, |
5370 | so we can do this anyway. */ | |
5371 | if (real_onep (arg1)) | |
5372 | return non_lvalue (convert (type, arg0)); | |
378393da RS |
5373 | |
5374 | /* Transform x * -1.0 into -x. This should be safe for NaNs, | |
5375 | signed zeros and signed infinities, but is currently | |
5376 | restricted to "unsafe math optimizations" just in case. */ | |
5377 | if (flag_unsafe_math_optimizations | |
5378 | && real_minus_onep (arg1)) | |
5379 | return fold (build1 (NEGATE_EXPR, type, arg0)); | |
5380 | ||
6d716ca8 | 5381 | /* x*2 is x+x */ |
43577e6b NB |
5382 | if (! wins && real_twop (arg1) |
5383 | && (*lang_hooks.decls.global_bindings_p) () == 0 | |
9ec36da5 | 5384 | && ! contains_placeholder_p (arg0)) |
6d716ca8 RS |
5385 | { |
5386 | tree arg = save_expr (arg0); | |
5387 | return build (PLUS_EXPR, type, arg, arg); | |
5388 | } | |
5389 | } | |
5390 | goto associate; | |
5391 | ||
5392 | case BIT_IOR_EXPR: | |
5393 | bit_ior: | |
5394 | if (integer_all_onesp (arg1)) | |
5395 | return omit_one_operand (type, arg1, arg0); | |
5396 | if (integer_zerop (arg1)) | |
5397 | return non_lvalue (convert (type, arg0)); | |
5398 | t1 = distribute_bit_expr (code, type, arg0, arg1); | |
5399 | if (t1 != NULL_TREE) | |
5400 | return t1; | |
85d2e16c | 5401 | |
ccc5fd95 JH |
5402 | /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))). |
5403 | ||
b6cc0a72 | 5404 | This results in more efficient code for machines without a NAND |
ccc5fd95 JH |
5405 | instruction. Combine will canonicalize to the first form |
5406 | which will allow use of NAND instructions provided by the | |
5407 | backend if they exist. */ | |
5408 | if (TREE_CODE (arg0) == BIT_NOT_EXPR | |
5409 | && TREE_CODE (arg1) == BIT_NOT_EXPR) | |
5410 | { | |
5411 | return fold (build1 (BIT_NOT_EXPR, type, | |
5412 | build (BIT_AND_EXPR, type, | |
5413 | TREE_OPERAND (arg0, 0), | |
5414 | TREE_OPERAND (arg1, 0)))); | |
5415 | } | |
5416 | ||
79e8185c JH |
5417 | /* See if this can be simplified into a rotate first. If that |
5418 | is unsuccessful continue in the association code. */ | |
5419 | goto bit_rotate; | |
6d716ca8 RS |
5420 | |
5421 | case BIT_XOR_EXPR: | |
5422 | if (integer_zerop (arg1)) | |
5423 | return non_lvalue (convert (type, arg0)); | |
5424 | if (integer_all_onesp (arg1)) | |
5425 | return fold (build1 (BIT_NOT_EXPR, type, arg0)); | |
79e8185c JH |
5426 | |
5427 | /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing | |
5428 | with a constant, and the two constants have no bits in common, | |
5429 | we should treat this as a BIT_IOR_EXPR since this may produce more | |
5430 | simplifications. */ | |
5431 | if (TREE_CODE (arg0) == BIT_AND_EXPR | |
5432 | && TREE_CODE (arg1) == BIT_AND_EXPR | |
5433 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
5434 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST | |
5435 | && integer_zerop (const_binop (BIT_AND_EXPR, | |
5436 | TREE_OPERAND (arg0, 1), | |
5437 | TREE_OPERAND (arg1, 1), 0))) | |
b6cc0a72 KH |
5438 | { |
5439 | code = BIT_IOR_EXPR; | |
5440 | goto bit_ior; | |
5441 | } | |
79e8185c | 5442 | |
03e0a65f | 5443 | /* See if this can be simplified into a rotate first. If that |
79e8185c | 5444 | is unsuccessful continue in the association code. */ |
03e0a65f | 5445 | goto bit_rotate; |
6d716ca8 RS |
5446 | |
5447 | case BIT_AND_EXPR: | |
5448 | bit_and: | |
5449 | if (integer_all_onesp (arg1)) | |
5450 | return non_lvalue (convert (type, arg0)); | |
5451 | if (integer_zerop (arg1)) | |
5452 | return omit_one_operand (type, arg1, arg0); | |
5453 | t1 = distribute_bit_expr (code, type, arg0, arg1); | |
5454 | if (t1 != NULL_TREE) | |
5455 | return t1; | |
5456 | /* Simplify ((int)c & 0x377) into (int)c, if c is unsigned char. */ | |
6d716ca8 RS |
5457 | if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR |
5458 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))) | |
5459 | { | |
770ae6cc RK |
5460 | unsigned int prec |
5461 | = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))); | |
5462 | ||
906c4e36 RK |
5463 | if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT |
5464 | && (~TREE_INT_CST_LOW (arg1) | |
5465 | & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0) | |
6d716ca8 RS |
5466 | return build1 (NOP_EXPR, type, TREE_OPERAND (arg0, 0)); |
5467 | } | |
ccc5fd95 | 5468 | |
a36335da | 5469 | /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))). |
ccc5fd95 | 5470 | |
b6cc0a72 | 5471 | This results in more efficient code for machines without a NOR |
ccc5fd95 JH |
5472 | instruction. Combine will canonicalize to the first form |
5473 | which will allow use of NOR instructions provided by the | |
5474 | backend if they exist. */ | |
5475 | if (TREE_CODE (arg0) == BIT_NOT_EXPR | |
5476 | && TREE_CODE (arg1) == BIT_NOT_EXPR) | |
5477 | { | |
5478 | return fold (build1 (BIT_NOT_EXPR, type, | |
5479 | build (BIT_IOR_EXPR, type, | |
5480 | TREE_OPERAND (arg0, 0), | |
5481 | TREE_OPERAND (arg1, 0)))); | |
5482 | } | |
5483 | ||
6d716ca8 RS |
5484 | goto associate; |
5485 | ||
5486 | case BIT_ANDTC_EXPR: | |
5487 | if (integer_all_onesp (arg0)) | |
5488 | return non_lvalue (convert (type, arg1)); | |
5489 | if (integer_zerop (arg0)) | |
5490 | return omit_one_operand (type, arg0, arg1); | |
5491 | if (TREE_CODE (arg1) == INTEGER_CST) | |
5492 | { | |
5493 | arg1 = fold (build1 (BIT_NOT_EXPR, type, arg1)); | |
5494 | code = BIT_AND_EXPR; | |
5495 | goto bit_and; | |
5496 | } | |
5497 | goto binary; | |
5498 | ||
e9aaa5a5 | 5499 | case RDIV_EXPR: |
b216cd4a ZW |
5500 | /* Don't touch a floating-point divide by zero unless the mode |
5501 | of the constant can represent infinity. */ | |
5502 | if (TREE_CODE (arg1) == REAL_CST | |
5503 | && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1))) | |
5504 | && real_zerop (arg1)) | |
e9aaa5a5 | 5505 | return t; |
e9aaa5a5 | 5506 | |
10414089 JL |
5507 | /* (-A) / (-B) -> A / B */ |
5508 | if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == NEGATE_EXPR) | |
5509 | return fold (build (RDIV_EXPR, type, TREE_OPERAND (arg0, 0), | |
5510 | TREE_OPERAND (arg1, 0))); | |
5511 | ||
e9aaa5a5 RK |
5512 | /* In IEEE floating point, x/1 is not equivalent to x for snans. |
5513 | However, ANSI says we can drop signals, so we can do this anyway. */ | |
5514 | if (real_onep (arg1)) | |
5515 | return non_lvalue (convert (type, arg0)); | |
5516 | ||
5517 | /* If ARG1 is a constant, we can convert this to a multiply by the | |
5518 | reciprocal. This does not have the same rounding properties, | |
de6c5979 BL |
5519 | so only do this if -funsafe-math-optimizations. We can actually |
5520 | always safely do it if ARG1 is a power of two, but it's hard to | |
5521 | tell if it is or not in a portable manner. */ | |
39647dcb RK |
5522 | if (TREE_CODE (arg1) == REAL_CST) |
5523 | { | |
de6c5979 | 5524 | if (flag_unsafe_math_optimizations |
39647dcb RK |
5525 | && 0 != (tem = const_binop (code, build_real (type, dconst1), |
5526 | arg1, 0))) | |
5527 | return fold (build (MULT_EXPR, type, arg0, tem)); | |
30f7a378 | 5528 | /* Find the reciprocal if optimizing and the result is exact. */ |
39647dcb RK |
5529 | else if (optimize) |
5530 | { | |
5531 | REAL_VALUE_TYPE r; | |
5532 | r = TREE_REAL_CST (arg1); | |
5533 | if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r)) | |
b6cc0a72 KH |
5534 | { |
5535 | tem = build_real (type, r); | |
5536 | return fold (build (MULT_EXPR, type, arg0, tem)); | |
5537 | } | |
39647dcb RK |
5538 | } |
5539 | } | |
bc8d3f91 JH |
5540 | /* Convert A/B/C to A/(B*C). */ |
5541 | if (flag_unsafe_math_optimizations | |
5542 | && TREE_CODE (arg0) == RDIV_EXPR) | |
5543 | { | |
5544 | return fold (build (RDIV_EXPR, type, TREE_OPERAND (arg0, 0), | |
5545 | build (MULT_EXPR, type, TREE_OPERAND (arg0, 1), | |
5546 | arg1))); | |
5547 | } | |
5548 | /* Convert A/(B/C) to (A/B)*C. */ | |
5549 | if (flag_unsafe_math_optimizations | |
5550 | && TREE_CODE (arg1) == RDIV_EXPR) | |
5551 | { | |
5552 | return fold (build (MULT_EXPR, type, | |
5553 | build (RDIV_EXPR, type, arg0, | |
5554 | TREE_OPERAND (arg1, 0)), | |
5555 | TREE_OPERAND (arg1, 1))); | |
5556 | } | |
e9aaa5a5 RK |
5557 | goto binary; |
5558 | ||
6d716ca8 RS |
5559 | case TRUNC_DIV_EXPR: |
5560 | case ROUND_DIV_EXPR: | |
5561 | case FLOOR_DIV_EXPR: | |
5562 | case CEIL_DIV_EXPR: | |
5563 | case EXACT_DIV_EXPR: | |
6d716ca8 RS |
5564 | if (integer_onep (arg1)) |
5565 | return non_lvalue (convert (type, arg0)); | |
5566 | if (integer_zerop (arg1)) | |
5567 | return t; | |
3b998c11 | 5568 | |
39dfb55a JL |
5569 | /* If arg0 is a multiple of arg1, then rewrite to the fastest div |
5570 | operation, EXACT_DIV_EXPR. | |
5571 | ||
91585c63 TM |
5572 | Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now. |
5573 | At one time others generated faster code, it's not clear if they do | |
5574 | after the last round to changes to the DIV code in expmed.c. */ | |
5575 | if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR) | |
39dfb55a JL |
5576 | && multiple_of_p (type, arg0, arg1)) |
5577 | return fold (build (EXACT_DIV_EXPR, type, arg0, arg1)); | |
5578 | ||
b6cc0a72 | 5579 | if (TREE_CODE (arg1) == INTEGER_CST |
1baa375f RK |
5580 | && 0 != (tem = extract_muldiv (TREE_OPERAND (t, 0), arg1, |
5581 | code, NULL_TREE))) | |
5582 | return convert (type, tem); | |
3b998c11 | 5583 | |
6d716ca8 RS |
5584 | goto binary; |
5585 | ||
5586 | case CEIL_MOD_EXPR: | |
5587 | case FLOOR_MOD_EXPR: | |
5588 | case ROUND_MOD_EXPR: | |
5589 | case TRUNC_MOD_EXPR: | |
5590 | if (integer_onep (arg1)) | |
5591 | return omit_one_operand (type, integer_zero_node, arg0); | |
5592 | if (integer_zerop (arg1)) | |
5593 | return t; | |
6a96fcb4 | 5594 | |
6a96fcb4 | 5595 | if (TREE_CODE (arg1) == INTEGER_CST |
1baa375f RK |
5596 | && 0 != (tem = extract_muldiv (TREE_OPERAND (t, 0), arg1, |
5597 | code, NULL_TREE))) | |
5598 | return convert (type, tem); | |
6a96fcb4 | 5599 | |
6d716ca8 RS |
5600 | goto binary; |
5601 | ||
5602 | case LSHIFT_EXPR: | |
5603 | case RSHIFT_EXPR: | |
5604 | case LROTATE_EXPR: | |
5605 | case RROTATE_EXPR: | |
5606 | if (integer_zerop (arg1)) | |
5607 | return non_lvalue (convert (type, arg0)); | |
5608 | /* Since negative shift count is not well-defined, | |
5609 | don't try to compute it in the compiler. */ | |
4d39710e | 5610 | if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0) |
6d716ca8 | 5611 | return t; |
4d39710e RK |
5612 | /* Rewrite an LROTATE_EXPR by a constant into an |
5613 | RROTATE_EXPR by a new constant. */ | |
5614 | if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST) | |
5615 | { | |
5616 | TREE_SET_CODE (t, RROTATE_EXPR); | |
5617 | code = RROTATE_EXPR; | |
5618 | TREE_OPERAND (t, 1) = arg1 | |
5619 | = const_binop | |
5620 | (MINUS_EXPR, | |
5621 | convert (TREE_TYPE (arg1), | |
5622 | build_int_2 (GET_MODE_BITSIZE (TYPE_MODE (type)), 0)), | |
5623 | arg1, 0); | |
5624 | if (tree_int_cst_sgn (arg1) < 0) | |
5625 | return t; | |
5626 | } | |
5627 | ||
5628 | /* If we have a rotate of a bit operation with the rotate count and | |
5629 | the second operand of the bit operation both constant, | |
5630 | permute the two operations. */ | |
5631 | if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
5632 | && (TREE_CODE (arg0) == BIT_AND_EXPR | |
5633 | || TREE_CODE (arg0) == BIT_ANDTC_EXPR | |
5634 | || TREE_CODE (arg0) == BIT_IOR_EXPR | |
5635 | || TREE_CODE (arg0) == BIT_XOR_EXPR) | |
5636 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
5637 | return fold (build (TREE_CODE (arg0), type, | |
5638 | fold (build (code, type, | |
5639 | TREE_OPERAND (arg0, 0), arg1)), | |
5640 | fold (build (code, type, | |
5641 | TREE_OPERAND (arg0, 1), arg1)))); | |
5642 | ||
5643 | /* Two consecutive rotates adding up to the width of the mode can | |
5644 | be ignored. */ | |
5645 | if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
5646 | && TREE_CODE (arg0) == RROTATE_EXPR | |
5647 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
5648 | && TREE_INT_CST_HIGH (arg1) == 0 | |
5649 | && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0 | |
5650 | && ((TREE_INT_CST_LOW (arg1) | |
5651 | + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))) | |
05bccae2 | 5652 | == (unsigned int) GET_MODE_BITSIZE (TYPE_MODE (type)))) |
4d39710e RK |
5653 | return TREE_OPERAND (arg0, 0); |
5654 | ||
6d716ca8 RS |
5655 | goto binary; |
5656 | ||
5657 | case MIN_EXPR: | |
5658 | if (operand_equal_p (arg0, arg1, 0)) | |
13eb1f7f | 5659 | return omit_one_operand (type, arg0, arg1); |
7178e3af | 5660 | if (INTEGRAL_TYPE_P (type) |
6d716ca8 RS |
5661 | && operand_equal_p (arg1, TYPE_MIN_VALUE (type), 1)) |
5662 | return omit_one_operand (type, arg1, arg0); | |
5663 | goto associate; | |
5664 | ||
5665 | case MAX_EXPR: | |
5666 | if (operand_equal_p (arg0, arg1, 0)) | |
13eb1f7f | 5667 | return omit_one_operand (type, arg0, arg1); |
7178e3af | 5668 | if (INTEGRAL_TYPE_P (type) |
e1ee5cdc | 5669 | && TYPE_MAX_VALUE (type) |
6d716ca8 RS |
5670 | && operand_equal_p (arg1, TYPE_MAX_VALUE (type), 1)) |
5671 | return omit_one_operand (type, arg1, arg0); | |
5672 | goto associate; | |
5673 | ||
5674 | case TRUTH_NOT_EXPR: | |
5675 | /* Note that the operand of this must be an int | |
5676 | and its values must be 0 or 1. | |
5677 | ("true" is a fixed value perhaps depending on the language, | |
5678 | but we don't handle values other than 1 correctly yet.) */ | |
1180eb10 JM |
5679 | tem = invert_truthvalue (arg0); |
5680 | /* Avoid infinite recursion. */ | |
5681 | if (TREE_CODE (tem) == TRUTH_NOT_EXPR) | |
5682 | return t; | |
5683 | return convert (type, tem); | |
6d716ca8 RS |
5684 | |
5685 | case TRUTH_ANDIF_EXPR: | |
5686 | /* Note that the operands of this must be ints | |
5687 | and their values must be 0 or 1. | |
5688 | ("true" is a fixed value perhaps depending on the language.) */ | |
5689 | /* If first arg is constant zero, return it. */ | |
772447c5 | 5690 | if (integer_zerop (arg0)) |
13eb1f7f | 5691 | return convert (type, arg0); |
6d716ca8 RS |
5692 | case TRUTH_AND_EXPR: |
5693 | /* If either arg is constant true, drop it. */ | |
5694 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
13eb1f7f | 5695 | return non_lvalue (convert (type, arg1)); |
235cfbc4 BS |
5696 | if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1) |
5697 | /* Preserve sequence points. */ | |
5698 | && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0))) | |
13eb1f7f | 5699 | return non_lvalue (convert (type, arg0)); |
772447c5 RK |
5700 | /* If second arg is constant zero, result is zero, but first arg |
5701 | must be evaluated. */ | |
5702 | if (integer_zerop (arg1)) | |
5703 | return omit_one_operand (type, arg1, arg0); | |
80906567 RK |
5704 | /* Likewise for first arg, but note that only the TRUTH_AND_EXPR |
5705 | case will be handled here. */ | |
5706 | if (integer_zerop (arg0)) | |
5707 | return omit_one_operand (type, arg0, arg1); | |
6d716ca8 RS |
5708 | |
5709 | truth_andor: | |
e9b5e15f RK |
5710 | /* We only do these simplifications if we are optimizing. */ |
5711 | if (!optimize) | |
5712 | return t; | |
5713 | ||
5714 | /* Check for things like (A || B) && (A || C). We can convert this | |
5715 | to A || (B && C). Note that either operator can be any of the four | |
5716 | truth and/or operations and the transformation will still be | |
5717 | valid. Also note that we only care about order for the | |
96f06cb6 | 5718 | ANDIF and ORIF operators. If B contains side effects, this |
30f7a378 | 5719 | might change the truth-value of A. */ |
e9b5e15f RK |
5720 | if (TREE_CODE (arg0) == TREE_CODE (arg1) |
5721 | && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR | |
5722 | || TREE_CODE (arg0) == TRUTH_ORIF_EXPR | |
5723 | || TREE_CODE (arg0) == TRUTH_AND_EXPR | |
96f06cb6 RK |
5724 | || TREE_CODE (arg0) == TRUTH_OR_EXPR) |
5725 | && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1))) | |
e9b5e15f RK |
5726 | { |
5727 | tree a00 = TREE_OPERAND (arg0, 0); | |
5728 | tree a01 = TREE_OPERAND (arg0, 1); | |
5729 | tree a10 = TREE_OPERAND (arg1, 0); | |
5730 | tree a11 = TREE_OPERAND (arg1, 1); | |
5731 | int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR | |
5732 | || TREE_CODE (arg0) == TRUTH_AND_EXPR) | |
5733 | && (code == TRUTH_AND_EXPR | |
5734 | || code == TRUTH_OR_EXPR)); | |
5735 | ||
5736 | if (operand_equal_p (a00, a10, 0)) | |
5737 | return fold (build (TREE_CODE (arg0), type, a00, | |
5738 | fold (build (code, type, a01, a11)))); | |
5739 | else if (commutative && operand_equal_p (a00, a11, 0)) | |
5740 | return fold (build (TREE_CODE (arg0), type, a00, | |
5741 | fold (build (code, type, a01, a10)))); | |
5742 | else if (commutative && operand_equal_p (a01, a10, 0)) | |
5743 | return fold (build (TREE_CODE (arg0), type, a01, | |
5744 | fold (build (code, type, a00, a11)))); | |
5745 | ||
5746 | /* This case if tricky because we must either have commutative | |
5747 | operators or else A10 must not have side-effects. */ | |
5748 | ||
5749 | else if ((commutative || ! TREE_SIDE_EFFECTS (a10)) | |
5750 | && operand_equal_p (a01, a11, 0)) | |
5751 | return fold (build (TREE_CODE (arg0), type, | |
5752 | fold (build (code, type, a00, a10)), | |
5753 | a01)); | |
5754 | } | |
5755 | ||
ebde8a27 RK |
5756 | /* See if we can build a range comparison. */ |
5757 | if (0 != (tem = fold_range_test (t))) | |
5758 | return tem; | |
5759 | ||
6d716ca8 RS |
5760 | /* Check for the possibility of merging component references. If our |
5761 | lhs is another similar operation, try to merge its rhs with our | |
5762 | rhs. Then try to merge our lhs and rhs. */ | |
e9b5e15f RK |
5763 | if (TREE_CODE (arg0) == code |
5764 | && 0 != (tem = fold_truthop (code, type, | |
5765 | TREE_OPERAND (arg0, 1), arg1))) | |
5766 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
6d716ca8 | 5767 | |
e9b5e15f RK |
5768 | if ((tem = fold_truthop (code, type, arg0, arg1)) != 0) |
5769 | return tem; | |
61f275ff | 5770 | |
6d716ca8 RS |
5771 | return t; |
5772 | ||
5773 | case TRUTH_ORIF_EXPR: | |
5774 | /* Note that the operands of this must be ints | |
5775 | and their values must be 0 or true. | |
5776 | ("true" is a fixed value perhaps depending on the language.) */ | |
5777 | /* If first arg is constant true, return it. */ | |
5778 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
13eb1f7f | 5779 | return convert (type, arg0); |
6d716ca8 RS |
5780 | case TRUTH_OR_EXPR: |
5781 | /* If either arg is constant zero, drop it. */ | |
5782 | if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0)) | |
13eb1f7f | 5783 | return non_lvalue (convert (type, arg1)); |
235cfbc4 BS |
5784 | if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1) |
5785 | /* Preserve sequence points. */ | |
5786 | && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0))) | |
13eb1f7f | 5787 | return non_lvalue (convert (type, arg0)); |
772447c5 RK |
5788 | /* If second arg is constant true, result is true, but we must |
5789 | evaluate first arg. */ | |
5790 | if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)) | |
5791 | return omit_one_operand (type, arg1, arg0); | |
80906567 RK |
5792 | /* Likewise for first arg, but note this only occurs here for |
5793 | TRUTH_OR_EXPR. */ | |
5794 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
5795 | return omit_one_operand (type, arg0, arg1); | |
6d716ca8 RS |
5796 | goto truth_andor; |
5797 | ||
772447c5 RK |
5798 | case TRUTH_XOR_EXPR: |
5799 | /* If either arg is constant zero, drop it. */ | |
5800 | if (integer_zerop (arg0)) | |
13eb1f7f | 5801 | return non_lvalue (convert (type, arg1)); |
772447c5 | 5802 | if (integer_zerop (arg1)) |
13eb1f7f | 5803 | return non_lvalue (convert (type, arg0)); |
772447c5 RK |
5804 | /* If either arg is constant true, this is a logical inversion. */ |
5805 | if (integer_onep (arg0)) | |
13eb1f7f | 5806 | return non_lvalue (convert (type, invert_truthvalue (arg1))); |
772447c5 | 5807 | if (integer_onep (arg1)) |
13eb1f7f | 5808 | return non_lvalue (convert (type, invert_truthvalue (arg0))); |
62d8b51e | 5809 | return t; |
772447c5 | 5810 | |
6d716ca8 RS |
5811 | case EQ_EXPR: |
5812 | case NE_EXPR: | |
5813 | case LT_EXPR: | |
5814 | case GT_EXPR: | |
5815 | case LE_EXPR: | |
5816 | case GE_EXPR: | |
10414089 JL |
5817 | if (FLOAT_TYPE_P (TREE_TYPE (arg0))) |
5818 | { | |
5819 | /* (-a) CMP (-b) -> b CMP a */ | |
5820 | if (TREE_CODE (arg0) == NEGATE_EXPR | |
5821 | && TREE_CODE (arg1) == NEGATE_EXPR) | |
5822 | return fold (build (code, type, TREE_OPERAND (arg1, 0), | |
5823 | TREE_OPERAND (arg0, 0))); | |
5824 | /* (-a) CMP CST -> a swap(CMP) (-CST) */ | |
5825 | if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == REAL_CST) | |
5826 | return | |
5827 | fold (build | |
b6cc0a72 KH |
5828 | (swap_tree_comparison (code), type, |
5829 | TREE_OPERAND (arg0, 0), | |
5830 | build_real (TREE_TYPE (arg1), | |
5831 | REAL_VALUE_NEGATE (TREE_REAL_CST (arg1))))); | |
10414089 JL |
5832 | /* IEEE doesn't distinguish +0 and -0 in comparisons. */ |
5833 | /* a CMP (-0) -> a CMP 0 */ | |
0d19c2a1 JL |
5834 | if (TREE_CODE (arg1) == REAL_CST |
5835 | && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (arg1))) | |
10414089 JL |
5836 | return fold (build (code, type, arg0, |
5837 | build_real (TREE_TYPE (arg1), dconst0))); | |
5838 | } | |
5839 | ||
6d716ca8 RS |
5840 | /* If one arg is a constant integer, put it last. */ |
5841 | if (TREE_CODE (arg0) == INTEGER_CST | |
5842 | && TREE_CODE (arg1) != INTEGER_CST) | |
5843 | { | |
5844 | TREE_OPERAND (t, 0) = arg1; | |
5845 | TREE_OPERAND (t, 1) = arg0; | |
5846 | arg0 = TREE_OPERAND (t, 0); | |
5847 | arg1 = TREE_OPERAND (t, 1); | |
c05a9b68 | 5848 | code = swap_tree_comparison (code); |
6d716ca8 RS |
5849 | TREE_SET_CODE (t, code); |
5850 | } | |
5851 | ||
5852 | /* Convert foo++ == CONST into ++foo == CONST + INCR. | |
5853 | First, see if one arg is constant; find the constant arg | |
5854 | and the other one. */ | |
5855 | { | |
4e86caed | 5856 | tree constop = 0, varop = NULL_TREE; |
cd7ece66 | 5857 | int constopnum = -1; |
6d716ca8 RS |
5858 | |
5859 | if (TREE_CONSTANT (arg1)) | |
cd7ece66 | 5860 | constopnum = 1, constop = arg1, varop = arg0; |
6d716ca8 | 5861 | if (TREE_CONSTANT (arg0)) |
cd7ece66 | 5862 | constopnum = 0, constop = arg0, varop = arg1; |
6d716ca8 RS |
5863 | |
5864 | if (constop && TREE_CODE (varop) == POSTINCREMENT_EXPR) | |
5865 | { | |
6d716ca8 RS |
5866 | /* This optimization is invalid for ordered comparisons |
5867 | if CONST+INCR overflows or if foo+incr might overflow. | |
c05a9b68 | 5868 | This optimization is invalid for floating point due to rounding. |
6d716ca8 | 5869 | For pointer types we assume overflow doesn't happen. */ |
e5e809f4 | 5870 | if (POINTER_TYPE_P (TREE_TYPE (varop)) |
7178e3af | 5871 | || (! FLOAT_TYPE_P (TREE_TYPE (varop)) |
c05a9b68 | 5872 | && (code == EQ_EXPR || code == NE_EXPR))) |
6d716ca8 | 5873 | { |
c05a9b68 RS |
5874 | tree newconst |
5875 | = fold (build (PLUS_EXPR, TREE_TYPE (varop), | |
5876 | constop, TREE_OPERAND (varop, 1))); | |
4d06bcc5 MM |
5877 | |
5878 | /* Do not overwrite the current varop to be a preincrement, | |
5879 | create a new node so that we won't confuse our caller who | |
5880 | might create trees and throw them away, reusing the | |
5881 | arguments that they passed to build. This shows up in | |
5882 | the THEN or ELSE parts of ?: being postincrements. */ | |
5883 | varop = build (PREINCREMENT_EXPR, TREE_TYPE (varop), | |
5884 | TREE_OPERAND (varop, 0), | |
5885 | TREE_OPERAND (varop, 1)); | |
cd7ece66 | 5886 | |
30eca391 RK |
5887 | /* If VAROP is a reference to a bitfield, we must mask |
5888 | the constant by the width of the field. */ | |
5889 | if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF | |
5890 | && DECL_BIT_FIELD(TREE_OPERAND | |
5891 | (TREE_OPERAND (varop, 0), 1))) | |
5892 | { | |
5893 | int size | |
5894 | = TREE_INT_CST_LOW (DECL_SIZE | |
5895 | (TREE_OPERAND | |
5896 | (TREE_OPERAND (varop, 0), 1))); | |
df0e526f | 5897 | tree mask, unsigned_type; |
770ae6cc | 5898 | unsigned int precision; |
df0e526f AS |
5899 | tree folded_compare; |
5900 | ||
5901 | /* First check whether the comparison would come out | |
5902 | always the same. If we don't do that we would | |
5903 | change the meaning with the masking. */ | |
5904 | if (constopnum == 0) | |
5905 | folded_compare = fold (build (code, type, constop, | |
5906 | TREE_OPERAND (varop, 0))); | |
5907 | else | |
5908 | folded_compare = fold (build (code, type, | |
5909 | TREE_OPERAND (varop, 0), | |
5910 | constop)); | |
5911 | if (integer_zerop (folded_compare) | |
5912 | || integer_onep (folded_compare)) | |
5913 | return omit_one_operand (type, folded_compare, varop); | |
5914 | ||
b0c48229 | 5915 | unsigned_type = (*lang_hooks.types.type_for_size)(size, 1); |
df0e526f AS |
5916 | precision = TYPE_PRECISION (unsigned_type); |
5917 | mask = build_int_2 (~0, ~0); | |
5918 | TREE_TYPE (mask) = unsigned_type; | |
5919 | force_fit_type (mask, 0); | |
5920 | mask = const_binop (RSHIFT_EXPR, mask, | |
5921 | size_int (precision - size), 0); | |
30eca391 RK |
5922 | newconst = fold (build (BIT_AND_EXPR, |
5923 | TREE_TYPE (varop), newconst, | |
5924 | convert (TREE_TYPE (varop), | |
df0e526f | 5925 | mask))); |
30eca391 | 5926 | } |
30eca391 | 5927 | |
4d06bcc5 MM |
5928 | t = build (code, type, |
5929 | (constopnum == 0) ? newconst : varop, | |
5930 | (constopnum == 1) ? newconst : varop); | |
c05a9b68 | 5931 | return t; |
6d716ca8 RS |
5932 | } |
5933 | } | |
5934 | else if (constop && TREE_CODE (varop) == POSTDECREMENT_EXPR) | |
5935 | { | |
e5e809f4 | 5936 | if (POINTER_TYPE_P (TREE_TYPE (varop)) |
7178e3af | 5937 | || (! FLOAT_TYPE_P (TREE_TYPE (varop)) |
c05a9b68 | 5938 | && (code == EQ_EXPR || code == NE_EXPR))) |
6d716ca8 | 5939 | { |
c05a9b68 RS |
5940 | tree newconst |
5941 | = fold (build (MINUS_EXPR, TREE_TYPE (varop), | |
5942 | constop, TREE_OPERAND (varop, 1))); | |
4d06bcc5 MM |
5943 | |
5944 | /* Do not overwrite the current varop to be a predecrement, | |
5945 | create a new node so that we won't confuse our caller who | |
5946 | might create trees and throw them away, reusing the | |
5947 | arguments that they passed to build. This shows up in | |
5948 | the THEN or ELSE parts of ?: being postdecrements. */ | |
5949 | varop = build (PREDECREMENT_EXPR, TREE_TYPE (varop), | |
5950 | TREE_OPERAND (varop, 0), | |
5951 | TREE_OPERAND (varop, 1)); | |
30eca391 RK |
5952 | |
5953 | if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF | |
5954 | && DECL_BIT_FIELD(TREE_OPERAND | |
5955 | (TREE_OPERAND (varop, 0), 1))) | |
5956 | { | |
5957 | int size | |
5958 | = TREE_INT_CST_LOW (DECL_SIZE | |
5959 | (TREE_OPERAND | |
5960 | (TREE_OPERAND (varop, 0), 1))); | |
df0e526f | 5961 | tree mask, unsigned_type; |
770ae6cc | 5962 | unsigned int precision; |
df0e526f AS |
5963 | tree folded_compare; |
5964 | ||
5965 | if (constopnum == 0) | |
5966 | folded_compare = fold (build (code, type, constop, | |
5967 | TREE_OPERAND (varop, 0))); | |
5968 | else | |
5969 | folded_compare = fold (build (code, type, | |
5970 | TREE_OPERAND (varop, 0), | |
5971 | constop)); | |
5972 | if (integer_zerop (folded_compare) | |
5973 | || integer_onep (folded_compare)) | |
5974 | return omit_one_operand (type, folded_compare, varop); | |
5975 | ||
b0c48229 | 5976 | unsigned_type = (*lang_hooks.types.type_for_size)(size, 1); |
df0e526f AS |
5977 | precision = TYPE_PRECISION (unsigned_type); |
5978 | mask = build_int_2 (~0, ~0); | |
5979 | TREE_TYPE (mask) = TREE_TYPE (varop); | |
5980 | force_fit_type (mask, 0); | |
5981 | mask = const_binop (RSHIFT_EXPR, mask, | |
5982 | size_int (precision - size), 0); | |
30eca391 RK |
5983 | newconst = fold (build (BIT_AND_EXPR, |
5984 | TREE_TYPE (varop), newconst, | |
5985 | convert (TREE_TYPE (varop), | |
df0e526f | 5986 | mask))); |
30eca391 | 5987 | } |
30eca391 | 5988 | |
4d06bcc5 MM |
5989 | t = build (code, type, |
5990 | (constopnum == 0) ? newconst : varop, | |
5991 | (constopnum == 1) ? newconst : varop); | |
c05a9b68 | 5992 | return t; |
6d716ca8 RS |
5993 | } |
5994 | } | |
5995 | } | |
5996 | ||
033afd11 RH |
5997 | /* Comparisons with the highest or lowest possible integer of |
5998 | the specified size will have known values and an unsigned | |
5999 | <= 0x7fffffff can be simplified. */ | |
6000 | { | |
6001 | int width = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg1))); | |
6002 | ||
6003 | if (TREE_CODE (arg1) == INTEGER_CST | |
6004 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
6005 | && width <= HOST_BITS_PER_WIDE_INT | |
6006 | && (INTEGRAL_TYPE_P (TREE_TYPE (arg1)) | |
6007 | || POINTER_TYPE_P (TREE_TYPE (arg1)))) | |
6008 | { | |
6009 | if (TREE_INT_CST_HIGH (arg1) == 0 | |
6010 | && (TREE_INT_CST_LOW (arg1) | |
6011 | == ((unsigned HOST_WIDE_INT) 1 << (width - 1)) - 1) | |
6012 | && ! TREE_UNSIGNED (TREE_TYPE (arg1))) | |
6013 | switch (TREE_CODE (t)) | |
6014 | { | |
6015 | case GT_EXPR: | |
6016 | return omit_one_operand (type, | |
6017 | convert (type, integer_zero_node), | |
6018 | arg0); | |
6019 | case GE_EXPR: | |
6020 | TREE_SET_CODE (t, EQ_EXPR); | |
6021 | break; | |
6022 | ||
6023 | case LE_EXPR: | |
6024 | return omit_one_operand (type, | |
6025 | convert (type, integer_one_node), | |
6026 | arg0); | |
6027 | case LT_EXPR: | |
6028 | TREE_SET_CODE (t, NE_EXPR); | |
6029 | break; | |
6030 | ||
6031 | default: | |
6032 | break; | |
6033 | } | |
6034 | ||
6035 | else if (TREE_INT_CST_HIGH (arg1) == -1 | |
6036 | && (TREE_INT_CST_LOW (arg1) | |
6037 | == ((unsigned HOST_WIDE_INT) -1 << (width - 1))) | |
6038 | && ! TREE_UNSIGNED (TREE_TYPE (arg1))) | |
6039 | switch (TREE_CODE (t)) | |
6040 | { | |
6041 | case LT_EXPR: | |
6042 | return omit_one_operand (type, | |
6043 | convert (type, integer_zero_node), | |
6044 | arg0); | |
6045 | case LE_EXPR: | |
6046 | TREE_SET_CODE (t, EQ_EXPR); | |
6047 | break; | |
6048 | ||
6049 | case GE_EXPR: | |
6050 | return omit_one_operand (type, | |
6051 | convert (type, integer_one_node), | |
6052 | arg0); | |
6053 | case GT_EXPR: | |
6054 | TREE_SET_CODE (t, NE_EXPR); | |
6055 | break; | |
6056 | ||
6057 | default: | |
6058 | break; | |
6059 | } | |
6060 | ||
6061 | else if (TREE_INT_CST_HIGH (arg1) == 0 | |
6062 | && (TREE_INT_CST_LOW (arg1) | |
6063 | == ((unsigned HOST_WIDE_INT) 1 << (width - 1)) - 1) | |
6064 | && TREE_UNSIGNED (TREE_TYPE (arg1)) | |
6065 | /* signed_type does not work on pointer types. */ | |
6066 | && INTEGRAL_TYPE_P (TREE_TYPE (arg1))) | |
6067 | { | |
6068 | if (TREE_CODE (t) == LE_EXPR || TREE_CODE (t) == GT_EXPR) | |
6069 | { | |
6070 | tree st0, st1; | |
6071 | st0 = (*lang_hooks.types.signed_type) (TREE_TYPE (arg0)); | |
6072 | st1 = (*lang_hooks.types.signed_type) (TREE_TYPE (arg1)); | |
6073 | return fold | |
6074 | (build (TREE_CODE (t) == LE_EXPR ? GE_EXPR: LT_EXPR, | |
6075 | type, convert (st0, arg0), | |
6076 | convert (st1, integer_zero_node))); | |
6077 | } | |
6078 | } | |
dd3f0101 | 6079 | else if (TREE_INT_CST_HIGH (arg1) == 0 |
033afd11 RH |
6080 | && (TREE_INT_CST_LOW (arg1) |
6081 | == ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1) | |
6082 | && TREE_UNSIGNED (TREE_TYPE (arg1))) | |
dd3f0101 KH |
6083 | switch (TREE_CODE (t)) |
6084 | { | |
6085 | case GT_EXPR: | |
6086 | return omit_one_operand (type, | |
6087 | convert (type, integer_zero_node), | |
6088 | arg0); | |
6089 | case GE_EXPR: | |
6090 | TREE_SET_CODE (t, EQ_EXPR); | |
6091 | break; | |
6092 | ||
6093 | case LE_EXPR: | |
6094 | return omit_one_operand (type, | |
6095 | convert (type, integer_one_node), | |
6096 | arg0); | |
6097 | case LT_EXPR: | |
6098 | TREE_SET_CODE (t, NE_EXPR); | |
6099 | break; | |
6100 | ||
6101 | default: | |
6102 | break; | |
6103 | } | |
033afd11 RH |
6104 | } |
6105 | } | |
6106 | ||
6107 | /* Change X >= C to X > C-1 and X < C to X <= C-1 if C is positive. */ | |
6d716ca8 RS |
6108 | if (TREE_CODE (arg1) == INTEGER_CST |
6109 | && TREE_CODE (arg0) != INTEGER_CST | |
d0cb4c65 | 6110 | && tree_int_cst_sgn (arg1) > 0) |
6d716ca8 RS |
6111 | { |
6112 | switch (TREE_CODE (t)) | |
6113 | { | |
6114 | case GE_EXPR: | |
6115 | code = GT_EXPR; | |
91d33e36 | 6116 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
cd7ece66 | 6117 | t = build (code, type, TREE_OPERAND (t, 0), arg1); |
6d716ca8 RS |
6118 | break; |
6119 | ||
6120 | case LT_EXPR: | |
6121 | code = LE_EXPR; | |
91d33e36 | 6122 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
cd7ece66 RK |
6123 | t = build (code, type, TREE_OPERAND (t, 0), arg1); |
6124 | break; | |
e9a25f70 JL |
6125 | |
6126 | default: | |
6127 | break; | |
6d716ca8 RS |
6128 | } |
6129 | } | |
6130 | ||
033afd11 RH |
6131 | /* An unsigned comparison against 0 can be simplified. */ |
6132 | if (integer_zerop (arg1) | |
6133 | && (INTEGRAL_TYPE_P (TREE_TYPE (arg1)) | |
6134 | || POINTER_TYPE_P (TREE_TYPE (arg1))) | |
6135 | && TREE_UNSIGNED (TREE_TYPE (arg1))) | |
6136 | { | |
6137 | switch (TREE_CODE (t)) | |
6138 | { | |
6139 | case GT_EXPR: | |
6140 | code = NE_EXPR; | |
6141 | TREE_SET_CODE (t, NE_EXPR); | |
6142 | break; | |
6143 | case LE_EXPR: | |
6144 | code = EQ_EXPR; | |
6145 | TREE_SET_CODE (t, EQ_EXPR); | |
6146 | break; | |
6147 | case GE_EXPR: | |
6148 | return omit_one_operand (type, | |
6149 | convert (type, integer_one_node), | |
6150 | arg0); | |
6151 | case LT_EXPR: | |
6152 | return omit_one_operand (type, | |
6153 | convert (type, integer_zero_node), | |
6154 | arg0); | |
6155 | default: | |
6156 | break; | |
6157 | } | |
6158 | } | |
6159 | ||
14a774a9 RK |
6160 | /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or |
6161 | a MINUS_EXPR of a constant, we can convert it into a comparison with | |
6162 | a revised constant as long as no overflow occurs. */ | |
6163 | if ((code == EQ_EXPR || code == NE_EXPR) | |
6164 | && TREE_CODE (arg1) == INTEGER_CST | |
6165 | && (TREE_CODE (arg0) == PLUS_EXPR | |
6166 | || TREE_CODE (arg0) == MINUS_EXPR) | |
6167 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
6168 | && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR | |
6169 | ? MINUS_EXPR : PLUS_EXPR, | |
6170 | arg1, TREE_OPERAND (arg0, 1), 0)) | |
6171 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
6172 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
6173 | ||
6174 | /* Similarly for a NEGATE_EXPR. */ | |
6175 | else if ((code == EQ_EXPR || code == NE_EXPR) | |
6176 | && TREE_CODE (arg0) == NEGATE_EXPR | |
6177 | && TREE_CODE (arg1) == INTEGER_CST | |
1baa375f | 6178 | && 0 != (tem = negate_expr (arg1)) |
14a774a9 RK |
6179 | && TREE_CODE (tem) == INTEGER_CST |
6180 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
6181 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
6182 | ||
6183 | /* If we have X - Y == 0, we can convert that to X == Y and similarly | |
6184 | for !=. Don't do this for ordered comparisons due to overflow. */ | |
6185 | else if ((code == NE_EXPR || code == EQ_EXPR) | |
6186 | && integer_zerop (arg1) && TREE_CODE (arg0) == MINUS_EXPR) | |
6187 | return fold (build (code, type, | |
6188 | TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1))); | |
6189 | ||
6190 | /* If we are widening one operand of an integer comparison, | |
6191 | see if the other operand is similarly being widened. Perhaps we | |
6192 | can do the comparison in the narrower type. */ | |
6193 | else if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE | |
6194 | && TREE_CODE (arg0) == NOP_EXPR | |
6195 | && (tem = get_unwidened (arg0, NULL_TREE)) != arg0 | |
6196 | && (t1 = get_unwidened (arg1, TREE_TYPE (tem))) != 0 | |
6197 | && (TREE_TYPE (t1) == TREE_TYPE (tem) | |
6198 | || (TREE_CODE (t1) == INTEGER_CST | |
6199 | && int_fits_type_p (t1, TREE_TYPE (tem))))) | |
6200 | return fold (build (code, type, tem, convert (TREE_TYPE (tem), t1))); | |
b6cc0a72 | 6201 | |
14a774a9 RK |
6202 | /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a |
6203 | constant, we can simplify it. */ | |
6204 | else if (TREE_CODE (arg1) == INTEGER_CST | |
6205 | && (TREE_CODE (arg0) == MIN_EXPR | |
6206 | || TREE_CODE (arg0) == MAX_EXPR) | |
6207 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
6208 | return optimize_minmax_comparison (t); | |
6209 | ||
6210 | /* If we are comparing an ABS_EXPR with a constant, we can | |
6211 | convert all the cases into explicit comparisons, but they may | |
6212 | well not be faster than doing the ABS and one comparison. | |
6213 | But ABS (X) <= C is a range comparison, which becomes a subtraction | |
6214 | and a comparison, and is probably faster. */ | |
6215 | else if (code == LE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
6216 | && TREE_CODE (arg0) == ABS_EXPR | |
1baa375f RK |
6217 | && ! TREE_SIDE_EFFECTS (arg0) |
6218 | && (0 != (tem = negate_expr (arg1))) | |
6219 | && TREE_CODE (tem) == INTEGER_CST | |
6220 | && ! TREE_CONSTANT_OVERFLOW (tem)) | |
6221 | return fold (build (TRUTH_ANDIF_EXPR, type, | |
6222 | build (GE_EXPR, type, TREE_OPERAND (arg0, 0), tem), | |
6223 | build (LE_EXPR, type, | |
6224 | TREE_OPERAND (arg0, 0), arg1))); | |
b6cc0a72 | 6225 | |
6d716ca8 RS |
6226 | /* If this is an EQ or NE comparison with zero and ARG0 is |
6227 | (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require | |
6228 | two operations, but the latter can be done in one less insn | |
e9a25f70 | 6229 | on machines that have only two-operand insns or on which a |
6d716ca8 RS |
6230 | constant cannot be the first operand. */ |
6231 | if (integer_zerop (arg1) && (code == EQ_EXPR || code == NE_EXPR) | |
6232 | && TREE_CODE (arg0) == BIT_AND_EXPR) | |
6233 | { | |
6234 | if (TREE_CODE (TREE_OPERAND (arg0, 0)) == LSHIFT_EXPR | |
6235 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 0), 0))) | |
6236 | return | |
6237 | fold (build (code, type, | |
6238 | build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
6239 | build (RSHIFT_EXPR, | |
6240 | TREE_TYPE (TREE_OPERAND (arg0, 0)), | |
6241 | TREE_OPERAND (arg0, 1), | |
6242 | TREE_OPERAND (TREE_OPERAND (arg0, 0), 1)), | |
6243 | convert (TREE_TYPE (arg0), | |
6244 | integer_one_node)), | |
6245 | arg1)); | |
6246 | else if (TREE_CODE (TREE_OPERAND (arg0, 1)) == LSHIFT_EXPR | |
6247 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 1), 0))) | |
6248 | return | |
6249 | fold (build (code, type, | |
6250 | build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
6251 | build (RSHIFT_EXPR, | |
6252 | TREE_TYPE (TREE_OPERAND (arg0, 1)), | |
6253 | TREE_OPERAND (arg0, 0), | |
6254 | TREE_OPERAND (TREE_OPERAND (arg0, 1), 1)), | |
6255 | convert (TREE_TYPE (arg0), | |
6256 | integer_one_node)), | |
6257 | arg1)); | |
6258 | } | |
6259 | ||
05a0d5ea | 6260 | /* If this is an NE or EQ comparison of zero against the result of a |
79bf94d3 RK |
6261 | signed MOD operation whose second operand is a power of 2, make |
6262 | the MOD operation unsigned since it is simpler and equivalent. */ | |
05a0d5ea RK |
6263 | if ((code == NE_EXPR || code == EQ_EXPR) |
6264 | && integer_zerop (arg1) | |
6265 | && ! TREE_UNSIGNED (TREE_TYPE (arg0)) | |
6266 | && (TREE_CODE (arg0) == TRUNC_MOD_EXPR | |
6267 | || TREE_CODE (arg0) == CEIL_MOD_EXPR | |
6268 | || TREE_CODE (arg0) == FLOOR_MOD_EXPR | |
79bf94d3 RK |
6269 | || TREE_CODE (arg0) == ROUND_MOD_EXPR) |
6270 | && integer_pow2p (TREE_OPERAND (arg0, 1))) | |
05a0d5ea | 6271 | { |
ceef8ce4 | 6272 | tree newtype = (*lang_hooks.types.unsigned_type) (TREE_TYPE (arg0)); |
05a0d5ea RK |
6273 | tree newmod = build (TREE_CODE (arg0), newtype, |
6274 | convert (newtype, TREE_OPERAND (arg0, 0)), | |
6275 | convert (newtype, TREE_OPERAND (arg0, 1))); | |
6276 | ||
6277 | return build (code, type, newmod, convert (newtype, arg1)); | |
6278 | } | |
6279 | ||
6d716ca8 RS |
6280 | /* If this is an NE comparison of zero with an AND of one, remove the |
6281 | comparison since the AND will give the correct value. */ | |
6282 | if (code == NE_EXPR && integer_zerop (arg1) | |
6283 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
6284 | && integer_onep (TREE_OPERAND (arg0, 1))) | |
6285 | return convert (type, arg0); | |
6286 | ||
6287 | /* If we have (A & C) == C where C is a power of 2, convert this into | |
6288 | (A & C) != 0. Similarly for NE_EXPR. */ | |
6289 | if ((code == EQ_EXPR || code == NE_EXPR) | |
6290 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
6291 | && integer_pow2p (TREE_OPERAND (arg0, 1)) | |
6292 | && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)) | |
1f77b5da RS |
6293 | return fold (build (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type, |
6294 | arg0, integer_zero_node)); | |
6295 | ||
6296 | /* If we have (A & C) != 0 where C is the sign bit of A, convert | |
6297 | this into A < 0. Similarly for (A & C) == 0 into A >= 0. */ | |
6298 | if ((code == EQ_EXPR || code == NE_EXPR) | |
6299 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
6300 | && integer_zerop (arg1)) | |
6301 | { | |
6302 | tree arg00 = sign_bit_p (TREE_OPERAND (arg0, 0), | |
6303 | TREE_OPERAND (arg0, 1)); | |
6304 | if (arg00 != NULL_TREE) | |
6305 | { | |
6306 | tree stype = (*lang_hooks.types.signed_type) (TREE_TYPE (arg00)); | |
6307 | return fold (build (code == EQ_EXPR ? GE_EXPR : LT_EXPR, type, | |
6308 | convert (stype, arg00), | |
6309 | convert (stype, integer_zero_node))); | |
6310 | } | |
6311 | } | |
6d716ca8 | 6312 | |
e92d3048 | 6313 | /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0 |
34b1b41f | 6314 | and similarly for >= into !=. */ |
e92d3048 RK |
6315 | if ((code == LT_EXPR || code == GE_EXPR) |
6316 | && TREE_UNSIGNED (TREE_TYPE (arg0)) | |
6317 | && TREE_CODE (arg1) == LSHIFT_EXPR | |
6318 | && integer_onep (TREE_OPERAND (arg1, 0))) | |
b6cc0a72 | 6319 | return build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type, |
e92d3048 RK |
6320 | build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0, |
6321 | TREE_OPERAND (arg1, 1)), | |
6322 | convert (TREE_TYPE (arg0), integer_zero_node)); | |
6323 | ||
6324 | else if ((code == LT_EXPR || code == GE_EXPR) | |
6325 | && TREE_UNSIGNED (TREE_TYPE (arg0)) | |
6326 | && (TREE_CODE (arg1) == NOP_EXPR | |
6327 | || TREE_CODE (arg1) == CONVERT_EXPR) | |
6328 | && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR | |
6329 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0))) | |
6330 | return | |
6331 | build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type, | |
6332 | convert (TREE_TYPE (arg0), | |
6333 | build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0, | |
6334 | TREE_OPERAND (TREE_OPERAND (arg1, 0), 1))), | |
6335 | convert (TREE_TYPE (arg0), integer_zero_node)); | |
6336 | ||
c05a9b68 RS |
6337 | /* Simplify comparison of something with itself. (For IEEE |
6338 | floating-point, we can only do some of these simplifications.) */ | |
6339 | if (operand_equal_p (arg0, arg1, 0)) | |
6d716ca8 RS |
6340 | { |
6341 | switch (code) | |
6342 | { | |
6343 | case EQ_EXPR: | |
6344 | case GE_EXPR: | |
6345 | case LE_EXPR: | |
1f2f8b29 | 6346 | if (! FLOAT_TYPE_P (TREE_TYPE (arg0))) |
f628873f | 6347 | return constant_boolean_node (1, type); |
c05a9b68 RS |
6348 | code = EQ_EXPR; |
6349 | TREE_SET_CODE (t, code); | |
6350 | break; | |
6351 | ||
6d716ca8 | 6352 | case NE_EXPR: |
c05a9b68 | 6353 | /* For NE, we can only do this simplification if integer. */ |
1f2f8b29 | 6354 | if (FLOAT_TYPE_P (TREE_TYPE (arg0))) |
c05a9b68 | 6355 | break; |
0f41302f | 6356 | /* ... fall through ... */ |
6d716ca8 RS |
6357 | case GT_EXPR: |
6358 | case LT_EXPR: | |
f628873f | 6359 | return constant_boolean_node (0, type); |
e9a25f70 JL |
6360 | default: |
6361 | abort (); | |
6d716ca8 RS |
6362 | } |
6363 | } | |
6364 | ||
c05a9b68 RS |
6365 | /* If we are comparing an expression that just has comparisons |
6366 | of two integer values, arithmetic expressions of those comparisons, | |
6367 | and constants, we can simplify it. There are only three cases | |
6368 | to check: the two values can either be equal, the first can be | |
6369 | greater, or the second can be greater. Fold the expression for | |
6370 | those three values. Since each value must be 0 or 1, we have | |
6371 | eight possibilities, each of which corresponds to the constant 0 | |
6372 | or 1 or one of the six possible comparisons. | |
6373 | ||
6374 | This handles common cases like (a > b) == 0 but also handles | |
6375 | expressions like ((x > y) - (y > x)) > 0, which supposedly | |
6376 | occur in macroized code. */ | |
6377 | ||
6378 | if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST) | |
6379 | { | |
6380 | tree cval1 = 0, cval2 = 0; | |
35e66bd1 | 6381 | int save_p = 0; |
c05a9b68 | 6382 | |
35e66bd1 | 6383 | if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p) |
c05a9b68 RS |
6384 | /* Don't handle degenerate cases here; they should already |
6385 | have been handled anyway. */ | |
6386 | && cval1 != 0 && cval2 != 0 | |
6387 | && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2)) | |
6388 | && TREE_TYPE (cval1) == TREE_TYPE (cval2) | |
7178e3af | 6389 | && INTEGRAL_TYPE_P (TREE_TYPE (cval1)) |
e1ee5cdc RH |
6390 | && TYPE_MAX_VALUE (TREE_TYPE (cval1)) |
6391 | && TYPE_MAX_VALUE (TREE_TYPE (cval2)) | |
c05a9b68 RS |
6392 | && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)), |
6393 | TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0)) | |
6394 | { | |
6395 | tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1)); | |
6396 | tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1)); | |
6397 | ||
6398 | /* We can't just pass T to eval_subst in case cval1 or cval2 | |
6399 | was the same as ARG1. */ | |
6400 | ||
6401 | tree high_result | |
6402 | = fold (build (code, type, | |
6403 | eval_subst (arg0, cval1, maxval, cval2, minval), | |
6404 | arg1)); | |
6405 | tree equal_result | |
6406 | = fold (build (code, type, | |
6407 | eval_subst (arg0, cval1, maxval, cval2, maxval), | |
6408 | arg1)); | |
6409 | tree low_result | |
6410 | = fold (build (code, type, | |
6411 | eval_subst (arg0, cval1, minval, cval2, maxval), | |
6412 | arg1)); | |
6413 | ||
6414 | /* All three of these results should be 0 or 1. Confirm they | |
6415 | are. Then use those values to select the proper code | |
6416 | to use. */ | |
6417 | ||
6418 | if ((integer_zerop (high_result) | |
6419 | || integer_onep (high_result)) | |
6420 | && (integer_zerop (equal_result) | |
6421 | || integer_onep (equal_result)) | |
6422 | && (integer_zerop (low_result) | |
6423 | || integer_onep (low_result))) | |
6424 | { | |
6425 | /* Make a 3-bit mask with the high-order bit being the | |
6426 | value for `>', the next for '=', and the low for '<'. */ | |
6427 | switch ((integer_onep (high_result) * 4) | |
6428 | + (integer_onep (equal_result) * 2) | |
6429 | + integer_onep (low_result)) | |
6430 | { | |
6431 | case 0: | |
6432 | /* Always false. */ | |
13837058 | 6433 | return omit_one_operand (type, integer_zero_node, arg0); |
c05a9b68 RS |
6434 | case 1: |
6435 | code = LT_EXPR; | |
6436 | break; | |
6437 | case 2: | |
6438 | code = EQ_EXPR; | |
6439 | break; | |
6440 | case 3: | |
6441 | code = LE_EXPR; | |
6442 | break; | |
6443 | case 4: | |
6444 | code = GT_EXPR; | |
6445 | break; | |
6446 | case 5: | |
6447 | code = NE_EXPR; | |
6448 | break; | |
6449 | case 6: | |
6450 | code = GE_EXPR; | |
6451 | break; | |
6452 | case 7: | |
6453 | /* Always true. */ | |
13837058 | 6454 | return omit_one_operand (type, integer_one_node, arg0); |
c05a9b68 RS |
6455 | } |
6456 | ||
35e66bd1 RK |
6457 | t = build (code, type, cval1, cval2); |
6458 | if (save_p) | |
6459 | return save_expr (t); | |
6460 | else | |
6461 | return fold (t); | |
c05a9b68 RS |
6462 | } |
6463 | } | |
6464 | } | |
6465 | ||
6466 | /* If this is a comparison of a field, we may be able to simplify it. */ | |
9c922ec7 MM |
6467 | if ((TREE_CODE (arg0) == COMPONENT_REF |
6468 | || TREE_CODE (arg0) == BIT_FIELD_REF) | |
6469 | && (code == EQ_EXPR || code == NE_EXPR) | |
6470 | /* Handle the constant case even without -O | |
6471 | to make sure the warnings are given. */ | |
6472 | && (optimize || TREE_CODE (arg1) == INTEGER_CST)) | |
6473 | { | |
6474 | t1 = optimize_bit_field_compare (code, type, arg0, arg1); | |
6475 | return t1 ? t1 : t; | |
6476 | } | |
c05a9b68 | 6477 | |
9ec36da5 JL |
6478 | /* If this is a comparison of complex values and either or both sides |
6479 | are a COMPLEX_EXPR or COMPLEX_CST, it is best to split up the | |
6480 | comparisons and join them with a TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR. | |
6481 | This may prevent needless evaluations. */ | |
95aa28ae RK |
6482 | if ((code == EQ_EXPR || code == NE_EXPR) |
6483 | && TREE_CODE (TREE_TYPE (arg0)) == COMPLEX_TYPE | |
6484 | && (TREE_CODE (arg0) == COMPLEX_EXPR | |
9ec36da5 JL |
6485 | || TREE_CODE (arg1) == COMPLEX_EXPR |
6486 | || TREE_CODE (arg0) == COMPLEX_CST | |
6487 | || TREE_CODE (arg1) == COMPLEX_CST)) | |
95aa28ae RK |
6488 | { |
6489 | tree subtype = TREE_TYPE (TREE_TYPE (arg0)); | |
f0b8d9aa AS |
6490 | tree real0, imag0, real1, imag1; |
6491 | ||
6492 | arg0 = save_expr (arg0); | |
6493 | arg1 = save_expr (arg1); | |
6494 | real0 = fold (build1 (REALPART_EXPR, subtype, arg0)); | |
6495 | imag0 = fold (build1 (IMAGPART_EXPR, subtype, arg0)); | |
6496 | real1 = fold (build1 (REALPART_EXPR, subtype, arg1)); | |
6497 | imag1 = fold (build1 (IMAGPART_EXPR, subtype, arg1)); | |
95aa28ae RK |
6498 | |
6499 | return fold (build ((code == EQ_EXPR ? TRUTH_ANDIF_EXPR | |
6500 | : TRUTH_ORIF_EXPR), | |
6501 | type, | |
6502 | fold (build (code, type, real0, real1)), | |
6503 | fold (build (code, type, imag0, imag1)))); | |
6504 | } | |
6505 | ||
d59b3b67 | 6506 | /* Optimize comparisons of strlen vs zero to a compare of the |
dd3f0101 | 6507 | first character of the string vs zero. To wit, |
d59b3b67 RS |
6508 | strlen(ptr) == 0 => *ptr == 0 |
6509 | strlen(ptr) != 0 => *ptr != 0 | |
6510 | Other cases should reduce to one of these two (or a constant) | |
6511 | due to the return value of strlen being unsigned. */ | |
6512 | if ((code == EQ_EXPR || code == NE_EXPR) | |
6513 | && integer_zerop (arg1) | |
6514 | && TREE_CODE (arg0) == CALL_EXPR | |
6515 | && TREE_CODE (TREE_OPERAND (arg0, 0)) == ADDR_EXPR) | |
6516 | { | |
6517 | tree fndecl = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0); | |
6518 | tree arglist; | |
6519 | ||
6520 | if (TREE_CODE (fndecl) == FUNCTION_DECL | |
6521 | && DECL_BUILT_IN (fndecl) | |
6522 | && DECL_BUILT_IN_CLASS (fndecl) != BUILT_IN_MD | |
6523 | && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN | |
6524 | && (arglist = TREE_OPERAND (arg0, 1)) | |
6525 | && TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) == POINTER_TYPE | |
6526 | && ! TREE_CHAIN (arglist)) | |
6527 | return fold (build (code, type, | |
6528 | build1 (INDIRECT_REF, char_type_node, | |
6529 | TREE_VALUE(arglist)), | |
6530 | integer_zero_node)); | |
6531 | } | |
6532 | ||
c05a9b68 RS |
6533 | /* From here on, the only cases we handle are when the result is |
6534 | known to be a constant. | |
6535 | ||
6536 | To compute GT, swap the arguments and do LT. | |
6d716ca8 RS |
6537 | To compute GE, do LT and invert the result. |
6538 | To compute LE, swap the arguments, do LT and invert the result. | |
c05a9b68 RS |
6539 | To compute NE, do EQ and invert the result. |
6540 | ||
6541 | Therefore, the code below must handle only EQ and LT. */ | |
6542 | ||
6d716ca8 RS |
6543 | if (code == LE_EXPR || code == GT_EXPR) |
6544 | { | |
c05a9b68 RS |
6545 | tem = arg0, arg0 = arg1, arg1 = tem; |
6546 | code = swap_tree_comparison (code); | |
6547 | } | |
6548 | ||
6549 | /* Note that it is safe to invert for real values here because we | |
6550 | will check below in the one case that it matters. */ | |
6551 | ||
14a774a9 | 6552 | t1 = NULL_TREE; |
c05a9b68 RS |
6553 | invert = 0; |
6554 | if (code == NE_EXPR || code == GE_EXPR) | |
6555 | { | |
6556 | invert = 1; | |
6557 | code = invert_tree_comparison (code); | |
6d716ca8 RS |
6558 | } |
6559 | ||
6560 | /* Compute a result for LT or EQ if args permit; | |
6561 | otherwise return T. */ | |
c05a9b68 | 6562 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) |
6d716ca8 | 6563 | { |
c05a9b68 | 6564 | if (code == EQ_EXPR) |
05bccae2 | 6565 | t1 = build_int_2 (tree_int_cst_equal (arg0, arg1), 0); |
6d716ca8 | 6566 | else |
c05a9b68 RS |
6567 | t1 = build_int_2 ((TREE_UNSIGNED (TREE_TYPE (arg0)) |
6568 | ? INT_CST_LT_UNSIGNED (arg0, arg1) | |
6569 | : INT_CST_LT (arg0, arg1)), | |
6570 | 0); | |
6d716ca8 | 6571 | } |
c05a9b68 | 6572 | |
e80c9ccb | 6573 | #if 0 /* This is no longer useful, but breaks some real code. */ |
6d716ca8 RS |
6574 | /* Assume a nonexplicit constant cannot equal an explicit one, |
6575 | since such code would be undefined anyway. | |
6576 | Exception: on sysvr4, using #pragma weak, | |
6577 | a label can come out as 0. */ | |
6578 | else if (TREE_CODE (arg1) == INTEGER_CST | |
6579 | && !integer_zerop (arg1) | |
6580 | && TREE_CONSTANT (arg0) | |
6581 | && TREE_CODE (arg0) == ADDR_EXPR | |
c05a9b68 RS |
6582 | && code == EQ_EXPR) |
6583 | t1 = build_int_2 (0, 0); | |
e80c9ccb | 6584 | #endif |
6d716ca8 | 6585 | /* Two real constants can be compared explicitly. */ |
c05a9b68 | 6586 | else if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST) |
6d716ca8 | 6587 | { |
c05a9b68 RS |
6588 | /* If either operand is a NaN, the result is false with two |
6589 | exceptions: First, an NE_EXPR is true on NaNs, but that case | |
6590 | is already handled correctly since we will be inverting the | |
6591 | result for NE_EXPR. Second, if we had inverted a LE_EXPR | |
6592 | or a GE_EXPR into a LT_EXPR, we must return true so that it | |
6593 | will be inverted into false. */ | |
6594 | ||
6595 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg0)) | |
6596 | || REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))) | |
6597 | t1 = build_int_2 (invert && code == LT_EXPR, 0); | |
6598 | ||
6599 | else if (code == EQ_EXPR) | |
6600 | t1 = build_int_2 (REAL_VALUES_EQUAL (TREE_REAL_CST (arg0), | |
6601 | TREE_REAL_CST (arg1)), | |
6602 | 0); | |
6d716ca8 | 6603 | else |
c05a9b68 RS |
6604 | t1 = build_int_2 (REAL_VALUES_LESS (TREE_REAL_CST (arg0), |
6605 | TREE_REAL_CST (arg1)), | |
6606 | 0); | |
6d716ca8 RS |
6607 | } |
6608 | ||
c05a9b68 RS |
6609 | if (t1 == NULL_TREE) |
6610 | return t; | |
6611 | ||
6612 | if (invert) | |
6613 | TREE_INT_CST_LOW (t1) ^= 1; | |
6614 | ||
6615 | TREE_TYPE (t1) = type; | |
c651e1e0 | 6616 | if (TREE_CODE (type) == BOOLEAN_TYPE) |
78ef5b89 | 6617 | return (*lang_hooks.truthvalue_conversion) (t1); |
c05a9b68 | 6618 | return t1; |
6d716ca8 RS |
6619 | |
6620 | case COND_EXPR: | |
a5e9b124 JW |
6621 | /* Pedantic ANSI C says that a conditional expression is never an lvalue, |
6622 | so all simple results must be passed through pedantic_non_lvalue. */ | |
6d716ca8 | 6623 | if (TREE_CODE (arg0) == INTEGER_CST) |
a5e9b124 JW |
6624 | return pedantic_non_lvalue |
6625 | (TREE_OPERAND (t, (integer_zerop (arg0) ? 2 : 1))); | |
6d716ca8 | 6626 | else if (operand_equal_p (arg1, TREE_OPERAND (expr, 2), 0)) |
4ab3cb65 | 6627 | return pedantic_omit_one_operand (type, arg1, arg0); |
6d716ca8 | 6628 | |
c05a9b68 RS |
6629 | /* If the second operand is zero, invert the comparison and swap |
6630 | the second and third operands. Likewise if the second operand | |
6631 | is constant and the third is not or if the third operand is | |
6632 | equivalent to the first operand of the comparison. */ | |
6d716ca8 | 6633 | |
c05a9b68 RS |
6634 | if (integer_zerop (arg1) |
6635 | || (TREE_CONSTANT (arg1) && ! TREE_CONSTANT (TREE_OPERAND (t, 2))) | |
6636 | || (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' | |
6637 | && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0), | |
6638 | TREE_OPERAND (t, 2), | |
6639 | TREE_OPERAND (arg0, 1)))) | |
6640 | { | |
6641 | /* See if this can be inverted. If it can't, possibly because | |
6642 | it was a floating-point inequality comparison, don't do | |
6643 | anything. */ | |
6644 | tem = invert_truthvalue (arg0); | |
6d716ca8 | 6645 | |
c05a9b68 RS |
6646 | if (TREE_CODE (tem) != TRUTH_NOT_EXPR) |
6647 | { | |
cd7ece66 RK |
6648 | t = build (code, type, tem, |
6649 | TREE_OPERAND (t, 2), TREE_OPERAND (t, 1)); | |
6650 | arg0 = tem; | |
a58bd508 MT |
6651 | /* arg1 should be the first argument of the new T. */ |
6652 | arg1 = TREE_OPERAND (t, 1); | |
3a96b5eb | 6653 | STRIP_NOPS (arg1); |
c05a9b68 RS |
6654 | } |
6655 | } | |
6d716ca8 | 6656 | |
c05a9b68 RS |
6657 | /* If we have A op B ? A : C, we may be able to convert this to a |
6658 | simpler expression, depending on the operation and the values | |
71925bc0 RS |
6659 | of B and C. Signed zeros prevent all of these transformations, |
6660 | for reasons given above each one. */ | |
6d716ca8 | 6661 | |
c05a9b68 RS |
6662 | if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' |
6663 | && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0), | |
71925bc0 RS |
6664 | arg1, TREE_OPERAND (arg0, 1)) |
6665 | && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1)))) | |
6d716ca8 | 6666 | { |
c05a9b68 RS |
6667 | tree arg2 = TREE_OPERAND (t, 2); |
6668 | enum tree_code comp_code = TREE_CODE (arg0); | |
6669 | ||
3a96b5eb RK |
6670 | STRIP_NOPS (arg2); |
6671 | ||
71925bc0 RS |
6672 | /* If we have A op 0 ? A : -A, consider applying the following |
6673 | transformations: | |
6674 | ||
6675 | A == 0? A : -A same as -A | |
6676 | A != 0? A : -A same as A | |
6677 | A >= 0? A : -A same as abs (A) | |
6678 | A > 0? A : -A same as abs (A) | |
6679 | A <= 0? A : -A same as -abs (A) | |
6680 | A < 0? A : -A same as -abs (A) | |
6681 | ||
6682 | None of these transformations work for modes with signed | |
6683 | zeros. If A is +/-0, the first two transformations will | |
6684 | change the sign of the result (from +0 to -0, or vice | |
6685 | versa). The last four will fix the sign of the result, | |
6686 | even though the original expressions could be positive or | |
6687 | negative, depending on the sign of A. | |
6688 | ||
6689 | Note that all these transformations are correct if A is | |
6690 | NaN, since the two alternatives (A and -A) are also NaNs. */ | |
68c6b3a9 DE |
6691 | if ((FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 1))) |
6692 | ? real_zerop (TREE_OPERAND (arg0, 1)) | |
6693 | : integer_zerop (TREE_OPERAND (arg0, 1))) | |
c05a9b68 RS |
6694 | && TREE_CODE (arg2) == NEGATE_EXPR |
6695 | && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0)) | |
6696 | switch (comp_code) | |
6697 | { | |
6698 | case EQ_EXPR: | |
c9869b75 | 6699 | return |
b8fbe62c RK |
6700 | pedantic_non_lvalue |
6701 | (convert (type, | |
6702 | negate_expr | |
6703 | (convert (TREE_TYPE (TREE_OPERAND (t, 1)), | |
6704 | arg1)))); | |
c05a9b68 | 6705 | case NE_EXPR: |
a5e9b124 | 6706 | return pedantic_non_lvalue (convert (type, arg1)); |
c05a9b68 RS |
6707 | case GE_EXPR: |
6708 | case GT_EXPR: | |
899f1ed6 | 6709 | if (TREE_UNSIGNED (TREE_TYPE (arg1))) |
ceef8ce4 NB |
6710 | arg1 = convert ((*lang_hooks.types.signed_type) |
6711 | (TREE_TYPE (arg1)), arg1); | |
a5e9b124 | 6712 | return pedantic_non_lvalue |
21403f14 RK |
6713 | (convert (type, fold (build1 (ABS_EXPR, |
6714 | TREE_TYPE (arg1), arg1)))); | |
c05a9b68 RS |
6715 | case LE_EXPR: |
6716 | case LT_EXPR: | |
899f1ed6 | 6717 | if (TREE_UNSIGNED (TREE_TYPE (arg1))) |
ceef8ce4 NB |
6718 | arg1 = convert ((lang_hooks.types.signed_type) |
6719 | (TREE_TYPE (arg1)), arg1); | |
a5e9b124 | 6720 | return pedantic_non_lvalue |
1baa375f RK |
6721 | (negate_expr (convert (type, |
6722 | fold (build1 (ABS_EXPR, | |
6723 | TREE_TYPE (arg1), | |
6724 | arg1))))); | |
e9a25f70 JL |
6725 | default: |
6726 | abort (); | |
c05a9b68 | 6727 | } |
6d716ca8 | 6728 | |
71925bc0 RS |
6729 | /* A != 0 ? A : 0 is simply A, unless A is -0. Likewise |
6730 | A == 0 ? A : 0 is always 0 unless A is -0. Note that | |
6731 | both transformations are correct when A is NaN: A != 0 | |
6732 | is then true, and A == 0 is false. */ | |
6d716ca8 | 6733 | |
29ebe69a | 6734 | if (integer_zerop (TREE_OPERAND (arg0, 1)) && integer_zerop (arg2)) |
c05a9b68 RS |
6735 | { |
6736 | if (comp_code == NE_EXPR) | |
a5e9b124 | 6737 | return pedantic_non_lvalue (convert (type, arg1)); |
c05a9b68 | 6738 | else if (comp_code == EQ_EXPR) |
a5e9b124 | 6739 | return pedantic_non_lvalue (convert (type, integer_zero_node)); |
c05a9b68 RS |
6740 | } |
6741 | ||
71925bc0 RS |
6742 | /* Try some transformations of A op B ? A : B. |
6743 | ||
6744 | A == B? A : B same as B | |
6745 | A != B? A : B same as A | |
6746 | A >= B? A : B same as max (A, B) | |
6747 | A > B? A : B same as max (B, A) | |
6748 | A <= B? A : B same as min (A, B) | |
6749 | A < B? A : B same as min (B, A) | |
6750 | ||
6751 | As above, these transformations don't work in the presence | |
6752 | of signed zeros. For example, if A and B are zeros of | |
6753 | opposite sign, the first two transformations will change | |
6754 | the sign of the result. In the last four, the original | |
6755 | expressions give different results for (A=+0, B=-0) and | |
6756 | (A=-0, B=+0), but the transformed expressions do not. | |
6757 | ||
6758 | The first two transformations are correct if either A or B | |
6759 | is a NaN. In the first transformation, the condition will | |
6760 | be false, and B will indeed be chosen. In the case of the | |
6761 | second transformation, the condition A != B will be true, | |
6762 | and A will be chosen. | |
6763 | ||
6764 | The conversions to max() and min() are not correct if B is | |
6765 | a number and A is not. The conditions in the original | |
6766 | expressions will be false, so all four give B. The min() | |
6767 | and max() versions would give a NaN instead. */ | |
c05a9b68 RS |
6768 | if (operand_equal_for_comparison_p (TREE_OPERAND (arg0, 1), |
6769 | arg2, TREE_OPERAND (arg0, 0))) | |
3a96b5eb RK |
6770 | { |
6771 | tree comp_op0 = TREE_OPERAND (arg0, 0); | |
6772 | tree comp_op1 = TREE_OPERAND (arg0, 1); | |
6773 | tree comp_type = TREE_TYPE (comp_op0); | |
6774 | ||
a7833bec JM |
6775 | /* Avoid adding NOP_EXPRs in case this is an lvalue. */ |
6776 | if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type)) | |
6777 | comp_type = type; | |
6778 | ||
3a96b5eb RK |
6779 | switch (comp_code) |
6780 | { | |
6781 | case EQ_EXPR: | |
6782 | return pedantic_non_lvalue (convert (type, arg2)); | |
6783 | case NE_EXPR: | |
6784 | return pedantic_non_lvalue (convert (type, arg1)); | |
6785 | case LE_EXPR: | |
6786 | case LT_EXPR: | |
e9a25f70 JL |
6787 | /* In C++ a ?: expression can be an lvalue, so put the |
6788 | operand which will be used if they are equal first | |
b6cc0a72 | 6789 | so that we can convert this back to the |
e9a25f70 | 6790 | corresponding COND_EXPR. */ |
71925bc0 RS |
6791 | if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))) |
6792 | return pedantic_non_lvalue | |
6793 | (convert (type, fold (build (MIN_EXPR, comp_type, | |
6794 | (comp_code == LE_EXPR | |
6795 | ? comp_op0 : comp_op1), | |
6796 | (comp_code == LE_EXPR | |
6797 | ? comp_op1 : comp_op0))))); | |
88a5cdb8 | 6798 | break; |
3a96b5eb RK |
6799 | case GE_EXPR: |
6800 | case GT_EXPR: | |
71925bc0 RS |
6801 | if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))) |
6802 | return pedantic_non_lvalue | |
6803 | (convert (type, fold (build (MAX_EXPR, comp_type, | |
6804 | (comp_code == GE_EXPR | |
6805 | ? comp_op0 : comp_op1), | |
6806 | (comp_code == GE_EXPR | |
6807 | ? comp_op1 : comp_op0))))); | |
88a5cdb8 | 6808 | break; |
e9a25f70 JL |
6809 | default: |
6810 | abort (); | |
3a96b5eb RK |
6811 | } |
6812 | } | |
c05a9b68 RS |
6813 | |
6814 | /* If this is A op C1 ? A : C2 with C1 and C2 constant integers, | |
6815 | we might still be able to simplify this. For example, | |
6816 | if C1 is one less or one more than C2, this might have started | |
53d2fb4f | 6817 | out as a MIN or MAX and been transformed by this function. |
7178e3af | 6818 | Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */ |
c05a9b68 | 6819 | |
7178e3af | 6820 | if (INTEGRAL_TYPE_P (type) |
53d2fb4f | 6821 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST |
c05a9b68 RS |
6822 | && TREE_CODE (arg2) == INTEGER_CST) |
6823 | switch (comp_code) | |
6824 | { | |
6825 | case EQ_EXPR: | |
6826 | /* We can replace A with C1 in this case. */ | |
cd7ece66 RK |
6827 | arg1 = convert (type, TREE_OPERAND (arg0, 1)); |
6828 | t = build (code, type, TREE_OPERAND (t, 0), arg1, | |
6829 | TREE_OPERAND (t, 2)); | |
c05a9b68 RS |
6830 | break; |
6831 | ||
6832 | case LT_EXPR: | |
6833 | /* If C1 is C2 + 1, this is min(A, C2). */ | |
6834 | if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), 1) | |
6835 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
6836 | const_binop (PLUS_EXPR, arg2, | |
91d33e36 | 6837 | integer_one_node, 0), 1)) |
a5e9b124 JW |
6838 | return pedantic_non_lvalue |
6839 | (fold (build (MIN_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
6840 | break; |
6841 | ||
6842 | case LE_EXPR: | |
6843 | /* If C1 is C2 - 1, this is min(A, C2). */ | |
6844 | if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), 1) | |
6845 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
6846 | const_binop (MINUS_EXPR, arg2, | |
91d33e36 | 6847 | integer_one_node, 0), 1)) |
a5e9b124 JW |
6848 | return pedantic_non_lvalue |
6849 | (fold (build (MIN_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
6850 | break; |
6851 | ||
6852 | case GT_EXPR: | |
6853 | /* If C1 is C2 - 1, this is max(A, C2). */ | |
6854 | if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), 1) | |
6855 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
6856 | const_binop (MINUS_EXPR, arg2, | |
91d33e36 | 6857 | integer_one_node, 0), 1)) |
a5e9b124 JW |
6858 | return pedantic_non_lvalue |
6859 | (fold (build (MAX_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
6860 | break; |
6861 | ||
6862 | case GE_EXPR: | |
6863 | /* If C1 is C2 + 1, this is max(A, C2). */ | |
6864 | if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), 1) | |
6865 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
6866 | const_binop (PLUS_EXPR, arg2, | |
91d33e36 | 6867 | integer_one_node, 0), 1)) |
a5e9b124 JW |
6868 | return pedantic_non_lvalue |
6869 | (fold (build (MAX_EXPR, type, arg1, arg2))); | |
c05a9b68 | 6870 | break; |
e9a25f70 JL |
6871 | case NE_EXPR: |
6872 | break; | |
6873 | default: | |
6874 | abort (); | |
c05a9b68 | 6875 | } |
6d716ca8 RS |
6876 | } |
6877 | ||
e1f56f62 RK |
6878 | /* If the second operand is simpler than the third, swap them |
6879 | since that produces better jump optimization results. */ | |
2f939d94 | 6880 | if ((TREE_CONSTANT (arg1) || DECL_P (arg1) |
e1f56f62 RK |
6881 | || TREE_CODE (arg1) == SAVE_EXPR) |
6882 | && ! (TREE_CONSTANT (TREE_OPERAND (t, 2)) | |
2f939d94 | 6883 | || DECL_P (TREE_OPERAND (t, 2)) |
e1f56f62 RK |
6884 | || TREE_CODE (TREE_OPERAND (t, 2)) == SAVE_EXPR)) |
6885 | { | |
6886 | /* See if this can be inverted. If it can't, possibly because | |
6887 | it was a floating-point inequality comparison, don't do | |
6888 | anything. */ | |
6889 | tem = invert_truthvalue (arg0); | |
6890 | ||
6891 | if (TREE_CODE (tem) != TRUTH_NOT_EXPR) | |
6892 | { | |
cd7ece66 RK |
6893 | t = build (code, type, tem, |
6894 | TREE_OPERAND (t, 2), TREE_OPERAND (t, 1)); | |
6895 | arg0 = tem; | |
c479c2ac JL |
6896 | /* arg1 should be the first argument of the new T. */ |
6897 | arg1 = TREE_OPERAND (t, 1); | |
3a96b5eb | 6898 | STRIP_NOPS (arg1); |
e1f56f62 RK |
6899 | } |
6900 | } | |
6901 | ||
c05a9b68 RS |
6902 | /* Convert A ? 1 : 0 to simply A. */ |
6903 | if (integer_onep (TREE_OPERAND (t, 1)) | |
6904 | && integer_zerop (TREE_OPERAND (t, 2)) | |
6905 | /* If we try to convert TREE_OPERAND (t, 0) to our type, the | |
b6cc0a72 | 6906 | call to fold will try to move the conversion inside |
c05a9b68 RS |
6907 | a COND, which will recurse. In that case, the COND_EXPR |
6908 | is probably the best choice, so leave it alone. */ | |
6909 | && type == TREE_TYPE (arg0)) | |
a5e9b124 | 6910 | return pedantic_non_lvalue (arg0); |
6d716ca8 | 6911 | |
c05a9b68 RS |
6912 | /* Look for expressions of the form A & 2 ? 2 : 0. The result of this |
6913 | operation is simply A & 2. */ | |
6d716ca8 RS |
6914 | |
6915 | if (integer_zerop (TREE_OPERAND (t, 2)) | |
6916 | && TREE_CODE (arg0) == NE_EXPR | |
6917 | && integer_zerop (TREE_OPERAND (arg0, 1)) | |
c05a9b68 RS |
6918 | && integer_pow2p (arg1) |
6919 | && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR | |
6920 | && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1), | |
6921 | arg1, 1)) | |
a5e9b124 | 6922 | return pedantic_non_lvalue (convert (type, TREE_OPERAND (arg0, 0))); |
6d716ca8 | 6923 | |
6d716ca8 RS |
6924 | return t; |
6925 | ||
6926 | case COMPOUND_EXPR: | |
b7647895 JW |
6927 | /* When pedantic, a compound expression can be neither an lvalue |
6928 | nor an integer constant expression. */ | |
6929 | if (TREE_SIDE_EFFECTS (arg0) || pedantic) | |
d023bff9 RS |
6930 | return t; |
6931 | /* Don't let (0, 0) be null pointer constant. */ | |
6932 | if (integer_zerop (arg1)) | |
13eb1f7f RK |
6933 | return build1 (NOP_EXPR, type, arg1); |
6934 | return convert (type, arg1); | |
6d716ca8 | 6935 | |
1cc1b11a RS |
6936 | case COMPLEX_EXPR: |
6937 | if (wins) | |
214d5b84 | 6938 | return build_complex (type, arg0, arg1); |
1cc1b11a RS |
6939 | return t; |
6940 | ||
6941 | case REALPART_EXPR: | |
a333b79f | 6942 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) |
1cc1b11a RS |
6943 | return t; |
6944 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
6945 | return omit_one_operand (type, TREE_OPERAND (arg0, 0), | |
6946 | TREE_OPERAND (arg0, 1)); | |
6947 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
6948 | return TREE_REALPART (arg0); | |
6949 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
a3279355 RK |
6950 | return fold (build (TREE_CODE (arg0), type, |
6951 | fold (build1 (REALPART_EXPR, type, | |
6952 | TREE_OPERAND (arg0, 0))), | |
6953 | fold (build1 (REALPART_EXPR, | |
6954 | type, TREE_OPERAND (arg0, 1))))); | |
1cc1b11a RS |
6955 | return t; |
6956 | ||
6957 | case IMAGPART_EXPR: | |
a333b79f | 6958 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) |
1cc1b11a RS |
6959 | return convert (type, integer_zero_node); |
6960 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
6961 | return omit_one_operand (type, TREE_OPERAND (arg0, 1), | |
6962 | TREE_OPERAND (arg0, 0)); | |
6963 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
6964 | return TREE_IMAGPART (arg0); | |
6965 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
a3279355 RK |
6966 | return fold (build (TREE_CODE (arg0), type, |
6967 | fold (build1 (IMAGPART_EXPR, type, | |
6968 | TREE_OPERAND (arg0, 0))), | |
6969 | fold (build1 (IMAGPART_EXPR, type, | |
6970 | TREE_OPERAND (arg0, 1))))); | |
1cc1b11a RS |
6971 | return t; |
6972 | ||
56c98e5b JM |
6973 | /* Pull arithmetic ops out of the CLEANUP_POINT_EXPR where |
6974 | appropriate. */ | |
6975 | case CLEANUP_POINT_EXPR: | |
b7f6588d | 6976 | if (! has_cleanups (arg0)) |
3ffcb234 | 6977 | return TREE_OPERAND (t, 0); |
56c98e5b JM |
6978 | |
6979 | { | |
6980 | enum tree_code code0 = TREE_CODE (arg0); | |
6981 | int kind0 = TREE_CODE_CLASS (code0); | |
6982 | tree arg00 = TREE_OPERAND (arg0, 0); | |
6983 | tree arg01; | |
6984 | ||
0982a4b8 | 6985 | if (kind0 == '1' || code0 == TRUTH_NOT_EXPR) |
b6cc0a72 | 6986 | return fold (build1 (code0, type, |
56c98e5b JM |
6987 | fold (build1 (CLEANUP_POINT_EXPR, |
6988 | TREE_TYPE (arg00), arg00)))); | |
0982a4b8 JM |
6989 | |
6990 | if (kind0 == '<' || kind0 == '2' | |
6991 | || code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR | |
6992 | || code0 == TRUTH_AND_EXPR || code0 == TRUTH_OR_EXPR | |
6993 | || code0 == TRUTH_XOR_EXPR) | |
6994 | { | |
6995 | arg01 = TREE_OPERAND (arg0, 1); | |
6996 | ||
b7f6588d JM |
6997 | if (TREE_CONSTANT (arg00) |
6998 | || ((code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR) | |
6999 | && ! has_cleanups (arg00))) | |
0982a4b8 JM |
7000 | return fold (build (code0, type, arg00, |
7001 | fold (build1 (CLEANUP_POINT_EXPR, | |
7002 | TREE_TYPE (arg01), arg01)))); | |
7003 | ||
b7f6588d | 7004 | if (TREE_CONSTANT (arg01)) |
0982a4b8 JM |
7005 | return fold (build (code0, type, |
7006 | fold (build1 (CLEANUP_POINT_EXPR, | |
7007 | TREE_TYPE (arg00), arg00)), | |
7008 | arg01)); | |
7009 | } | |
56c98e5b JM |
7010 | |
7011 | return t; | |
7012 | } | |
7013 | ||
b0b3afb2 BS |
7014 | case CALL_EXPR: |
7015 | /* Check for a built-in function. */ | |
7016 | if (TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR | |
7017 | && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (expr, 0), 0)) | |
7018 | == FUNCTION_DECL) | |
7019 | && DECL_BUILT_IN (TREE_OPERAND (TREE_OPERAND (expr, 0), 0))) | |
7020 | { | |
7021 | tree tmp = fold_builtin (expr); | |
7022 | if (tmp) | |
7023 | return tmp; | |
7024 | } | |
7025 | return t; | |
7026 | ||
6d716ca8 RS |
7027 | default: |
7028 | return t; | |
7029 | } /* switch (code) */ | |
7030 | } | |
39dfb55a | 7031 | |
c5c76735 JL |
7032 | /* Determine if first argument is a multiple of second argument. Return 0 if |
7033 | it is not, or we cannot easily determined it to be. | |
39dfb55a | 7034 | |
c5c76735 JL |
7035 | An example of the sort of thing we care about (at this point; this routine |
7036 | could surely be made more general, and expanded to do what the *_DIV_EXPR's | |
7037 | fold cases do now) is discovering that | |
39dfb55a JL |
7038 | |
7039 | SAVE_EXPR (I) * SAVE_EXPR (J * 8) | |
7040 | ||
7041 | is a multiple of | |
7042 | ||
7043 | SAVE_EXPR (J * 8) | |
7044 | ||
c5c76735 | 7045 | when we know that the two SAVE_EXPR (J * 8) nodes are the same node. |
39dfb55a JL |
7046 | |
7047 | This code also handles discovering that | |
7048 | ||
7049 | SAVE_EXPR (I) * SAVE_EXPR (J * 8) | |
7050 | ||
c5c76735 | 7051 | is a multiple of 8 so we don't have to worry about dealing with a |
39dfb55a JL |
7052 | possible remainder. |
7053 | ||
c5c76735 JL |
7054 | Note that we *look* inside a SAVE_EXPR only to determine how it was |
7055 | calculated; it is not safe for fold to do much of anything else with the | |
7056 | internals of a SAVE_EXPR, since it cannot know when it will be evaluated | |
7057 | at run time. For example, the latter example above *cannot* be implemented | |
7058 | as SAVE_EXPR (I) * J or any variant thereof, since the value of J at | |
7059 | evaluation time of the original SAVE_EXPR is not necessarily the same at | |
7060 | the time the new expression is evaluated. The only optimization of this | |
39dfb55a JL |
7061 | sort that would be valid is changing |
7062 | ||
7063 | SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8) | |
39dfb55a | 7064 | |
c5c76735 | 7065 | divided by 8 to |
39dfb55a JL |
7066 | |
7067 | SAVE_EXPR (I) * SAVE_EXPR (J) | |
7068 | ||
7069 | (where the same SAVE_EXPR (J) is used in the original and the | |
7070 | transformed version). */ | |
7071 | ||
7072 | static int | |
7073 | multiple_of_p (type, top, bottom) | |
7074 | tree type; | |
7075 | tree top; | |
7076 | tree bottom; | |
7077 | { | |
7078 | if (operand_equal_p (top, bottom, 0)) | |
7079 | return 1; | |
7080 | ||
7081 | if (TREE_CODE (type) != INTEGER_TYPE) | |
7082 | return 0; | |
7083 | ||
7084 | switch (TREE_CODE (top)) | |
7085 | { | |
7086 | case MULT_EXPR: | |
7087 | return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom) | |
7088 | || multiple_of_p (type, TREE_OPERAND (top, 1), bottom)); | |
7089 | ||
7090 | case PLUS_EXPR: | |
7091 | case MINUS_EXPR: | |
7092 | return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom) | |
7093 | && multiple_of_p (type, TREE_OPERAND (top, 1), bottom)); | |
7094 | ||
fba2c0cd JJ |
7095 | case LSHIFT_EXPR: |
7096 | if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST) | |
7097 | { | |
7098 | tree op1, t1; | |
7099 | ||
7100 | op1 = TREE_OPERAND (top, 1); | |
7101 | /* const_binop may not detect overflow correctly, | |
7102 | so check for it explicitly here. */ | |
7103 | if (TYPE_PRECISION (TREE_TYPE (size_one_node)) | |
7104 | > TREE_INT_CST_LOW (op1) | |
7105 | && TREE_INT_CST_HIGH (op1) == 0 | |
7106 | && 0 != (t1 = convert (type, | |
7107 | const_binop (LSHIFT_EXPR, size_one_node, | |
7108 | op1, 0))) | |
7109 | && ! TREE_OVERFLOW (t1)) | |
7110 | return multiple_of_p (type, t1, bottom); | |
7111 | } | |
7112 | return 0; | |
7113 | ||
39dfb55a | 7114 | case NOP_EXPR: |
c5c76735 | 7115 | /* Can't handle conversions from non-integral or wider integral type. */ |
39dfb55a JL |
7116 | if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE) |
7117 | || (TYPE_PRECISION (type) | |
7118 | < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0))))) | |
7119 | return 0; | |
c5c76735 | 7120 | |
30f7a378 | 7121 | /* .. fall through ... */ |
c5c76735 | 7122 | |
39dfb55a JL |
7123 | case SAVE_EXPR: |
7124 | return multiple_of_p (type, TREE_OPERAND (top, 0), bottom); | |
7125 | ||
7126 | case INTEGER_CST: | |
fba2c0cd JJ |
7127 | if (TREE_CODE (bottom) != INTEGER_CST |
7128 | || (TREE_UNSIGNED (type) | |
7129 | && (tree_int_cst_sgn (top) < 0 | |
7130 | || tree_int_cst_sgn (bottom) < 0))) | |
39dfb55a JL |
7131 | return 0; |
7132 | return integer_zerop (const_binop (TRUNC_MOD_EXPR, | |
7133 | top, bottom, 0)); | |
7134 | ||
7135 | default: | |
7136 | return 0; | |
7137 | } | |
7138 | } | |
a36556a8 ZW |
7139 | |
7140 | /* Return true if `t' is known to be non-negative. */ | |
7141 | ||
7142 | int | |
7143 | tree_expr_nonnegative_p (t) | |
7144 | tree t; | |
7145 | { | |
7146 | switch (TREE_CODE (t)) | |
7147 | { | |
88e3805d KG |
7148 | case ABS_EXPR: |
7149 | case FFS_EXPR: | |
7150 | return 1; | |
a36556a8 ZW |
7151 | case INTEGER_CST: |
7152 | return tree_int_cst_sgn (t) >= 0; | |
ada11335 KG |
7153 | case TRUNC_DIV_EXPR: |
7154 | case CEIL_DIV_EXPR: | |
7155 | case FLOOR_DIV_EXPR: | |
7156 | case ROUND_DIV_EXPR: | |
7157 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)) | |
dd3f0101 | 7158 | && tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); |
ada11335 KG |
7159 | case TRUNC_MOD_EXPR: |
7160 | case CEIL_MOD_EXPR: | |
7161 | case FLOOR_MOD_EXPR: | |
7162 | case ROUND_MOD_EXPR: | |
7163 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)); | |
a36556a8 ZW |
7164 | case COND_EXPR: |
7165 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)) | |
7166 | && tree_expr_nonnegative_p (TREE_OPERAND (t, 2)); | |
88e3805d KG |
7167 | case COMPOUND_EXPR: |
7168 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
7169 | case MIN_EXPR: | |
7170 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)) | |
dd3f0101 | 7171 | && tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); |
88e3805d KG |
7172 | case MAX_EXPR: |
7173 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)) | |
dd3f0101 | 7174 | || tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); |
88e3805d KG |
7175 | case MODIFY_EXPR: |
7176 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
a36556a8 ZW |
7177 | case BIND_EXPR: |
7178 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); | |
ada11335 KG |
7179 | case SAVE_EXPR: |
7180 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)); | |
7181 | case NON_LVALUE_EXPR: | |
7182 | return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)); | |
a36556a8 ZW |
7183 | case RTL_EXPR: |
7184 | return rtl_expr_nonnegative_p (RTL_EXPR_RTL (t)); | |
dd3f0101 | 7185 | |
a36556a8 | 7186 | default: |
9d2dc7da KG |
7187 | if (truth_value_p (TREE_CODE (t))) |
7188 | /* Truth values evaluate to 0 or 1, which is nonnegative. */ | |
7189 | return 1; | |
7190 | else | |
7191 | /* We don't know sign of `t', so be conservative and return false. */ | |
7192 | return 0; | |
a36556a8 ZW |
7193 | } |
7194 | } | |
7195 | ||
7196 | /* Return true if `r' is known to be non-negative. | |
7197 | Only handles constants at the moment. */ | |
7198 | ||
7199 | int | |
7200 | rtl_expr_nonnegative_p (r) | |
7201 | rtx r; | |
7202 | { | |
7203 | switch (GET_CODE (r)) | |
7204 | { | |
7205 | case CONST_INT: | |
7206 | return INTVAL (r) >= 0; | |
7207 | ||
7208 | case CONST_DOUBLE: | |
7209 | if (GET_MODE (r) == VOIDmode) | |
7210 | return CONST_DOUBLE_HIGH (r) >= 0; | |
7211 | return 0; | |
7212 | ||
69ef87e2 AH |
7213 | case CONST_VECTOR: |
7214 | { | |
7215 | int units, i; | |
7216 | rtx elt; | |
7217 | ||
7218 | units = CONST_VECTOR_NUNITS (r); | |
7219 | ||
7220 | for (i = 0; i < units; ++i) | |
7221 | { | |
7222 | elt = CONST_VECTOR_ELT (r, i); | |
7223 | if (!rtl_expr_nonnegative_p (elt)) | |
7224 | return 0; | |
7225 | } | |
7226 | ||
7227 | return 1; | |
7228 | } | |
7229 | ||
a36556a8 ZW |
7230 | case SYMBOL_REF: |
7231 | case LABEL_REF: | |
7232 | /* These are always nonnegative. */ | |
7233 | return 1; | |
7234 | ||
7235 | default: | |
7236 | return 0; | |
7237 | } | |
7238 | } | |
e2500fed GK |
7239 | |
7240 | #include "gt-fold-const.h" |