]>
Commit | Line | Data |
---|---|---|
6d716ca8 | 1 | /* Fold a constant sub-tree into a single node for C-compiler |
f8dac6eb | 2 | Copyright (C) 1987, 88, 92-97, 1998 Free Software Foundation, Inc. |
6d716ca8 RS |
3 | |
4 | This file is part of GNU CC. | |
5 | ||
6 | GNU CC is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 2, or (at your option) | |
9 | any later version. | |
10 | ||
11 | GNU CC is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GNU CC; see the file COPYING. If not, write to | |
a35311b0 RK |
18 | the Free Software Foundation, 59 Temple Place - Suite 330, |
19 | Boston, MA 02111-1307, USA. */ | |
6d716ca8 | 20 | |
6dc42e49 | 21 | /*@@ This file should be rewritten to use an arbitrary precision |
6d716ca8 RS |
22 | @@ representation for "struct tree_int_cst" and "struct tree_real_cst". |
23 | @@ Perhaps the routines could also be used for bc/dc, and made a lib. | |
24 | @@ The routines that translate from the ap rep should | |
25 | @@ warn if precision et. al. is lost. | |
26 | @@ This would also make life easier when this technology is used | |
27 | @@ for cross-compilers. */ | |
28 | ||
29 | ||
f8dac6eb | 30 | /* The entry points in this file are fold, size_int_wide, size_binop |
0da6f3db | 31 | and force_fit_type. |
6d716ca8 RS |
32 | |
33 | fold takes a tree as argument and returns a simplified tree. | |
34 | ||
35 | size_binop takes a tree code for an arithmetic operation | |
36 | and two operands that are trees, and produces a tree for the | |
37 | result, assuming the type comes from `sizetype'. | |
38 | ||
39 | size_int takes an integer value, and creates a tree constant | |
0da6f3db DE |
40 | with type from `sizetype'. |
41 | ||
42 | force_fit_type takes a constant and prior overflow indicator, and | |
43 | forces the value to fit the type. It returns an overflow indicator. */ | |
44 | ||
e9a25f70 | 45 | #include "config.h" |
2fde567e | 46 | #include "system.h" |
6d716ca8 | 47 | #include <setjmp.h> |
6d716ca8 RS |
48 | #include "flags.h" |
49 | #include "tree.h" | |
10f0ad3d | 50 | #include "toplev.h" |
6d716ca8 | 51 | |
7c7b029d RS |
52 | /* Handle floating overflow for `const_binop'. */ |
53 | static jmp_buf float_error; | |
54 | ||
ebde8a27 RK |
55 | static void encode PROTO((HOST_WIDE_INT *, |
56 | HOST_WIDE_INT, HOST_WIDE_INT)); | |
57 | static void decode PROTO((HOST_WIDE_INT *, | |
58 | HOST_WIDE_INT *, HOST_WIDE_INT *)); | |
59 | int div_and_round_double PROTO((enum tree_code, int, HOST_WIDE_INT, | |
6dc7571d RK |
60 | HOST_WIDE_INT, HOST_WIDE_INT, |
61 | HOST_WIDE_INT, HOST_WIDE_INT *, | |
62 | HOST_WIDE_INT *, HOST_WIDE_INT *, | |
63 | HOST_WIDE_INT *)); | |
ebde8a27 RK |
64 | static int split_tree PROTO((tree, enum tree_code, tree *, |
65 | tree *, int *)); | |
e9a25f70 | 66 | static tree int_const_binop PROTO((enum tree_code, tree, tree, int, int)); |
ebde8a27 RK |
67 | static tree const_binop PROTO((enum tree_code, tree, tree, int)); |
68 | static tree fold_convert PROTO((tree, tree)); | |
6dc7571d RK |
69 | static enum tree_code invert_tree_comparison PROTO((enum tree_code)); |
70 | static enum tree_code swap_tree_comparison PROTO((enum tree_code)); | |
ebde8a27 | 71 | static int truth_value_p PROTO((enum tree_code)); |
6dc7571d | 72 | static int operand_equal_for_comparison_p PROTO((tree, tree, tree)); |
ebde8a27 RK |
73 | static int twoval_comparison_p PROTO((tree, tree *, tree *, int *)); |
74 | static tree eval_subst PROTO((tree, tree, tree, tree, tree)); | |
75 | static tree omit_one_operand PROTO((tree, tree, tree)); | |
4ab3cb65 | 76 | static tree pedantic_omit_one_operand PROTO((tree, tree, tree)); |
6dc7571d | 77 | static tree distribute_bit_expr PROTO((enum tree_code, tree, tree, tree)); |
ebde8a27 | 78 | static tree make_bit_field_ref PROTO((tree, tree, int, int, int)); |
6dc7571d RK |
79 | static tree optimize_bit_field_compare PROTO((enum tree_code, tree, |
80 | tree, tree)); | |
81 | static tree decode_field_reference PROTO((tree, int *, int *, | |
82 | enum machine_mode *, int *, | |
d4453ee5 | 83 | int *, tree *, tree *)); |
ebde8a27 RK |
84 | static int all_ones_mask_p PROTO((tree, int)); |
85 | static int simple_operand_p PROTO((tree)); | |
86 | static tree range_binop PROTO((enum tree_code, tree, tree, int, | |
87 | tree, int)); | |
88 | static tree make_range PROTO((tree, int *, tree *, tree *)); | |
89 | static tree build_range_check PROTO((tree, tree, int, tree, tree)); | |
90 | static int merge_ranges PROTO((int *, tree *, tree *, int, tree, tree, | |
91 | int, tree, tree)); | |
92 | static tree fold_range_test PROTO((tree)); | |
93 | static tree unextend PROTO((tree, int, int, tree)); | |
94 | static tree fold_truthop PROTO((enum tree_code, tree, tree, tree)); | |
b5f3b6b6 | 95 | static tree strip_compound_expr PROTO((tree, tree)); |
39dfb55a | 96 | static int multiple_of_p PROTO((tree, tree, tree)); |
d35357ed RS |
97 | |
98 | #ifndef BRANCH_COST | |
99 | #define BRANCH_COST 1 | |
100 | #endif | |
fe3e8e40 | 101 | |
fe3e8e40 RS |
102 | /* Suppose A1 + B1 = SUM1, using 2's complement arithmetic ignoring overflow. |
103 | Suppose A, B and SUM have the same respective signs as A1, B1, and SUM1. | |
104 | Then this yields nonzero if overflow occurred during the addition. | |
105 | Overflow occurs if A and B have the same sign, but A and SUM differ in sign. | |
106 | Use `^' to test whether signs differ, and `< 0' to isolate the sign. */ | |
107 | #define overflow_sum_sign(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0) | |
6d716ca8 | 108 | \f |
906c4e36 | 109 | /* To do constant folding on INTEGER_CST nodes requires two-word arithmetic. |
37bdb7e3 TG |
110 | We do that by representing the two-word integer in 4 words, with only |
111 | HOST_BITS_PER_WIDE_INT/2 bits stored in each word, as a positive number. */ | |
112 | ||
113 | #define LOWPART(x) \ | |
114 | ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT/2)) - 1)) | |
115 | #define HIGHPART(x) \ | |
116 | ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT/2) | |
117 | #define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT/2) | |
6d716ca8 | 118 | |
37bdb7e3 | 119 | /* Unpack a two-word integer into 4 words. |
906c4e36 | 120 | LOW and HI are the integer, as two `HOST_WIDE_INT' pieces. |
37bdb7e3 | 121 | WORDS points to the array of HOST_WIDE_INTs. */ |
6d716ca8 RS |
122 | |
123 | static void | |
37bdb7e3 TG |
124 | encode (words, low, hi) |
125 | HOST_WIDE_INT *words; | |
906c4e36 | 126 | HOST_WIDE_INT low, hi; |
6d716ca8 | 127 | { |
37bdb7e3 TG |
128 | words[0] = LOWPART (low); |
129 | words[1] = HIGHPART (low); | |
130 | words[2] = LOWPART (hi); | |
131 | words[3] = HIGHPART (hi); | |
6d716ca8 RS |
132 | } |
133 | ||
37bdb7e3 TG |
134 | /* Pack an array of 4 words into a two-word integer. |
135 | WORDS points to the array of words. | |
906c4e36 | 136 | The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */ |
6d716ca8 RS |
137 | |
138 | static void | |
37bdb7e3 TG |
139 | decode (words, low, hi) |
140 | HOST_WIDE_INT *words; | |
906c4e36 | 141 | HOST_WIDE_INT *low, *hi; |
6d716ca8 | 142 | { |
37bdb7e3 TG |
143 | *low = words[0] | words[1] * BASE; |
144 | *hi = words[2] | words[3] * BASE; | |
6d716ca8 RS |
145 | } |
146 | \f | |
147 | /* Make the integer constant T valid for its type | |
148 | by setting to 0 or 1 all the bits in the constant | |
e0f776fb RS |
149 | that don't belong in the type. |
150 | Yield 1 if a signed overflow occurs, 0 otherwise. | |
a4d8855c | 151 | If OVERFLOW is nonzero, a signed overflow has already occurred |
649ff3b4 RK |
152 | in calculating T, so propagate it. |
153 | ||
154 | Make the real constant T valid for its type by calling CHECK_FLOAT_VALUE, | |
155 | if it exists. */ | |
6d716ca8 | 156 | |
e0f776fb RS |
157 | int |
158 | force_fit_type (t, overflow) | |
6d716ca8 | 159 | tree t; |
e0f776fb | 160 | int overflow; |
6d716ca8 | 161 | { |
ef2bf0c0 RS |
162 | HOST_WIDE_INT low, high; |
163 | register int prec; | |
6d716ca8 | 164 | |
649ff3b4 RK |
165 | if (TREE_CODE (t) == REAL_CST) |
166 | { | |
167 | #ifdef CHECK_FLOAT_VALUE | |
168 | CHECK_FLOAT_VALUE (TYPE_MODE (TREE_TYPE (t)), TREE_REAL_CST (t), | |
169 | overflow); | |
170 | #endif | |
171 | return overflow; | |
172 | } | |
173 | ||
174 | else if (TREE_CODE (t) != INTEGER_CST) | |
ef2bf0c0 RS |
175 | return overflow; |
176 | ||
177 | low = TREE_INT_CST_LOW (t); | |
178 | high = TREE_INT_CST_HIGH (t); | |
42f769c1 | 179 | |
e5e809f4 | 180 | if (POINTER_TYPE_P (TREE_TYPE (t))) |
6d716ca8 | 181 | prec = POINTER_SIZE; |
ef2bf0c0 RS |
182 | else |
183 | prec = TYPE_PRECISION (TREE_TYPE (t)); | |
6d716ca8 RS |
184 | |
185 | /* First clear all bits that are beyond the type's precision. */ | |
186 | ||
906c4e36 | 187 | if (prec == 2 * HOST_BITS_PER_WIDE_INT) |
6d716ca8 | 188 | ; |
906c4e36 | 189 | else if (prec > HOST_BITS_PER_WIDE_INT) |
6d716ca8 RS |
190 | { |
191 | TREE_INT_CST_HIGH (t) | |
906c4e36 | 192 | &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT)); |
6d716ca8 RS |
193 | } |
194 | else | |
195 | { | |
196 | TREE_INT_CST_HIGH (t) = 0; | |
906c4e36 RK |
197 | if (prec < HOST_BITS_PER_WIDE_INT) |
198 | TREE_INT_CST_LOW (t) &= ~((HOST_WIDE_INT) (-1) << prec); | |
6d716ca8 RS |
199 | } |
200 | ||
e0f776fb RS |
201 | /* Unsigned types do not suffer sign extension or overflow. */ |
202 | if (TREE_UNSIGNED (TREE_TYPE (t))) | |
a7a05640 | 203 | return overflow; |
6d716ca8 | 204 | |
e0f776fb RS |
205 | /* If the value's sign bit is set, extend the sign. */ |
206 | if (prec != 2 * HOST_BITS_PER_WIDE_INT | |
906c4e36 RK |
207 | && (prec > HOST_BITS_PER_WIDE_INT |
208 | ? (TREE_INT_CST_HIGH (t) | |
209 | & ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1))) | |
210 | : TREE_INT_CST_LOW (t) & ((HOST_WIDE_INT) 1 << (prec - 1)))) | |
6d716ca8 RS |
211 | { |
212 | /* Value is negative: | |
213 | set to 1 all the bits that are outside this type's precision. */ | |
906c4e36 | 214 | if (prec > HOST_BITS_PER_WIDE_INT) |
6d716ca8 RS |
215 | { |
216 | TREE_INT_CST_HIGH (t) | |
906c4e36 | 217 | |= ((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT)); |
6d716ca8 RS |
218 | } |
219 | else | |
220 | { | |
221 | TREE_INT_CST_HIGH (t) = -1; | |
906c4e36 RK |
222 | if (prec < HOST_BITS_PER_WIDE_INT) |
223 | TREE_INT_CST_LOW (t) |= ((HOST_WIDE_INT) (-1) << prec); | |
6d716ca8 RS |
224 | } |
225 | } | |
e0f776fb RS |
226 | |
227 | /* Yield nonzero if signed overflow occurred. */ | |
228 | return | |
229 | ((overflow | (low ^ TREE_INT_CST_LOW (t)) | (high ^ TREE_INT_CST_HIGH (t))) | |
230 | != 0); | |
6d716ca8 RS |
231 | } |
232 | \f | |
906c4e36 RK |
233 | /* Add two doubleword integers with doubleword result. |
234 | Each argument is given as two `HOST_WIDE_INT' pieces. | |
6d716ca8 | 235 | One argument is L1 and H1; the other, L2 and H2. |
37bdb7e3 | 236 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 237 | |
fe3e8e40 | 238 | int |
6d716ca8 | 239 | add_double (l1, h1, l2, h2, lv, hv) |
906c4e36 RK |
240 | HOST_WIDE_INT l1, h1, l2, h2; |
241 | HOST_WIDE_INT *lv, *hv; | |
6d716ca8 | 242 | { |
37bdb7e3 | 243 | HOST_WIDE_INT l, h; |
6d716ca8 | 244 | |
37bdb7e3 TG |
245 | l = l1 + l2; |
246 | h = h1 + h2 + ((unsigned HOST_WIDE_INT) l < l1); | |
6d716ca8 | 247 | |
37bdb7e3 TG |
248 | *lv = l; |
249 | *hv = h; | |
250 | return overflow_sum_sign (h1, h2, h); | |
6d716ca8 RS |
251 | } |
252 | ||
906c4e36 | 253 | /* Negate a doubleword integer with doubleword result. |
fe3e8e40 | 254 | Return nonzero if the operation overflows, assuming it's signed. |
906c4e36 | 255 | The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1. |
37bdb7e3 | 256 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 257 | |
fe3e8e40 | 258 | int |
6d716ca8 | 259 | neg_double (l1, h1, lv, hv) |
906c4e36 RK |
260 | HOST_WIDE_INT l1, h1; |
261 | HOST_WIDE_INT *lv, *hv; | |
6d716ca8 RS |
262 | { |
263 | if (l1 == 0) | |
264 | { | |
265 | *lv = 0; | |
266 | *hv = - h1; | |
e0f776fb | 267 | return (*hv & h1) < 0; |
6d716ca8 RS |
268 | } |
269 | else | |
270 | { | |
271 | *lv = - l1; | |
272 | *hv = ~ h1; | |
fe3e8e40 | 273 | return 0; |
6d716ca8 RS |
274 | } |
275 | } | |
276 | \f | |
906c4e36 | 277 | /* Multiply two doubleword integers with doubleword result. |
fe3e8e40 | 278 | Return nonzero if the operation overflows, assuming it's signed. |
906c4e36 | 279 | Each argument is given as two `HOST_WIDE_INT' pieces. |
6d716ca8 | 280 | One argument is L1 and H1; the other, L2 and H2. |
37bdb7e3 | 281 | The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 282 | |
fe3e8e40 | 283 | int |
6d716ca8 | 284 | mul_double (l1, h1, l2, h2, lv, hv) |
906c4e36 RK |
285 | HOST_WIDE_INT l1, h1, l2, h2; |
286 | HOST_WIDE_INT *lv, *hv; | |
6d716ca8 | 287 | { |
37bdb7e3 TG |
288 | HOST_WIDE_INT arg1[4]; |
289 | HOST_WIDE_INT arg2[4]; | |
290 | HOST_WIDE_INT prod[4 * 2]; | |
291 | register unsigned HOST_WIDE_INT carry; | |
6d716ca8 | 292 | register int i, j, k; |
fe3e8e40 | 293 | HOST_WIDE_INT toplow, tophigh, neglow, neghigh; |
6d716ca8 | 294 | |
6d716ca8 RS |
295 | encode (arg1, l1, h1); |
296 | encode (arg2, l2, h2); | |
297 | ||
4c9a05bc | 298 | bzero ((char *) prod, sizeof prod); |
6d716ca8 | 299 | |
37bdb7e3 TG |
300 | for (i = 0; i < 4; i++) |
301 | { | |
302 | carry = 0; | |
303 | for (j = 0; j < 4; j++) | |
304 | { | |
305 | k = i + j; | |
306 | /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */ | |
307 | carry += arg1[i] * arg2[j]; | |
308 | /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */ | |
309 | carry += prod[k]; | |
310 | prod[k] = LOWPART (carry); | |
311 | carry = HIGHPART (carry); | |
312 | } | |
313 | prod[i + 4] = carry; | |
314 | } | |
6d716ca8 | 315 | |
37bdb7e3 | 316 | decode (prod, lv, hv); /* This ignores prod[4] through prod[4*2-1] */ |
fe3e8e40 RS |
317 | |
318 | /* Check for overflow by calculating the top half of the answer in full; | |
319 | it should agree with the low half's sign bit. */ | |
37bdb7e3 | 320 | decode (prod+4, &toplow, &tophigh); |
fe3e8e40 RS |
321 | if (h1 < 0) |
322 | { | |
323 | neg_double (l2, h2, &neglow, &neghigh); | |
324 | add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh); | |
325 | } | |
326 | if (h2 < 0) | |
327 | { | |
328 | neg_double (l1, h1, &neglow, &neghigh); | |
329 | add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh); | |
330 | } | |
331 | return (*hv < 0 ? ~(toplow & tophigh) : toplow | tophigh) != 0; | |
6d716ca8 RS |
332 | } |
333 | \f | |
906c4e36 | 334 | /* Shift the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 RS |
335 | keeping only PREC bits of result. |
336 | Shift right if COUNT is negative. | |
337 | ARITH nonzero specifies arithmetic shifting; otherwise use logical shift. | |
906c4e36 | 338 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 | 339 | |
e0f776fb | 340 | void |
6d716ca8 | 341 | lshift_double (l1, h1, count, prec, lv, hv, arith) |
6dc7571d RK |
342 | HOST_WIDE_INT l1, h1, count; |
343 | int prec; | |
906c4e36 | 344 | HOST_WIDE_INT *lv, *hv; |
6d716ca8 RS |
345 | int arith; |
346 | { | |
6d716ca8 RS |
347 | if (count < 0) |
348 | { | |
349 | rshift_double (l1, h1, - count, prec, lv, hv, arith); | |
e0f776fb | 350 | return; |
6d716ca8 | 351 | } |
37bdb7e3 | 352 | |
3d1877b1 RK |
353 | #ifdef SHIFT_COUNT_TRUNCATED |
354 | if (SHIFT_COUNT_TRUNCATED) | |
355 | count %= prec; | |
356 | #endif | |
6d716ca8 | 357 | |
37bdb7e3 | 358 | if (count >= HOST_BITS_PER_WIDE_INT) |
6d716ca8 | 359 | { |
2fde567e | 360 | *hv = (unsigned HOST_WIDE_INT) l1 << (count - HOST_BITS_PER_WIDE_INT); |
37bdb7e3 TG |
361 | *lv = 0; |
362 | } | |
363 | else | |
364 | { | |
365 | *hv = (((unsigned HOST_WIDE_INT) h1 << count) | |
2fde567e | 366 | | ((unsigned HOST_WIDE_INT) l1 >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1)); |
37bdb7e3 | 367 | *lv = (unsigned HOST_WIDE_INT) l1 << count; |
6d716ca8 | 368 | } |
6d716ca8 RS |
369 | } |
370 | ||
906c4e36 | 371 | /* Shift the doubleword integer in L1, H1 right by COUNT places |
6d716ca8 RS |
372 | keeping only PREC bits of result. COUNT must be positive. |
373 | ARITH nonzero specifies arithmetic shifting; otherwise use logical shift. | |
906c4e36 | 374 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
375 | |
376 | void | |
377 | rshift_double (l1, h1, count, prec, lv, hv, arith) | |
6dc7571d RK |
378 | HOST_WIDE_INT l1, h1, count; |
379 | int prec; | |
906c4e36 | 380 | HOST_WIDE_INT *lv, *hv; |
6d716ca8 RS |
381 | int arith; |
382 | { | |
37bdb7e3 TG |
383 | unsigned HOST_WIDE_INT signmask; |
384 | signmask = (arith | |
385 | ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1)) | |
386 | : 0); | |
6d716ca8 | 387 | |
3d1877b1 RK |
388 | #ifdef SHIFT_COUNT_TRUNCATED |
389 | if (SHIFT_COUNT_TRUNCATED) | |
390 | count %= prec; | |
391 | #endif | |
6d716ca8 | 392 | |
37bdb7e3 | 393 | if (count >= HOST_BITS_PER_WIDE_INT) |
6d716ca8 | 394 | { |
37bdb7e3 | 395 | *hv = signmask; |
2fde567e KG |
396 | *lv = ((signmask << (2 * HOST_BITS_PER_WIDE_INT - count - 1) << 1) |
397 | | ((unsigned HOST_WIDE_INT) h1 >> (count - HOST_BITS_PER_WIDE_INT))); | |
37bdb7e3 TG |
398 | } |
399 | else | |
400 | { | |
401 | *lv = (((unsigned HOST_WIDE_INT) l1 >> count) | |
2fde567e KG |
402 | | ((unsigned HOST_WIDE_INT) h1 << (HOST_BITS_PER_WIDE_INT - count - 1) << 1)); |
403 | *hv = ((signmask << (HOST_BITS_PER_WIDE_INT - count)) | |
37bdb7e3 | 404 | | ((unsigned HOST_WIDE_INT) h1 >> count)); |
6d716ca8 | 405 | } |
6d716ca8 RS |
406 | } |
407 | \f | |
37bdb7e3 | 408 | /* Rotate the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 RS |
409 | keeping only PREC bits of result. |
410 | Rotate right if COUNT is negative. | |
906c4e36 | 411 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
412 | |
413 | void | |
414 | lrotate_double (l1, h1, count, prec, lv, hv) | |
6dc7571d RK |
415 | HOST_WIDE_INT l1, h1, count; |
416 | int prec; | |
906c4e36 | 417 | HOST_WIDE_INT *lv, *hv; |
6d716ca8 | 418 | { |
4d39710e | 419 | HOST_WIDE_INT s1l, s1h, s2l, s2h; |
6d716ca8 | 420 | |
4d39710e | 421 | count %= prec; |
6d716ca8 | 422 | if (count < 0) |
4d39710e | 423 | count += prec; |
6d716ca8 | 424 | |
4d39710e RK |
425 | lshift_double (l1, h1, count, prec, &s1l, &s1h, 0); |
426 | rshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0); | |
427 | *lv = s1l | s2l; | |
428 | *hv = s1h | s2h; | |
6d716ca8 RS |
429 | } |
430 | ||
906c4e36 | 431 | /* Rotate the doubleword integer in L1, H1 left by COUNT places |
6d716ca8 | 432 | keeping only PREC bits of result. COUNT must be positive. |
906c4e36 | 433 | Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */ |
6d716ca8 RS |
434 | |
435 | void | |
436 | rrotate_double (l1, h1, count, prec, lv, hv) | |
6dc7571d RK |
437 | HOST_WIDE_INT l1, h1, count; |
438 | int prec; | |
906c4e36 | 439 | HOST_WIDE_INT *lv, *hv; |
6d716ca8 | 440 | { |
4d39710e | 441 | HOST_WIDE_INT s1l, s1h, s2l, s2h; |
6d716ca8 | 442 | |
4d39710e RK |
443 | count %= prec; |
444 | if (count < 0) | |
445 | count += prec; | |
6d716ca8 | 446 | |
4d39710e RK |
447 | rshift_double (l1, h1, count, prec, &s1l, &s1h, 0); |
448 | lshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0); | |
449 | *lv = s1l | s2l; | |
450 | *hv = s1h | s2h; | |
6d716ca8 RS |
451 | } |
452 | \f | |
906c4e36 | 453 | /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN |
6d716ca8 RS |
454 | for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM). |
455 | CODE is a tree code for a kind of division, one of | |
456 | TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR | |
457 | or EXACT_DIV_EXPR | |
fe3e8e40 RS |
458 | It controls how the quotient is rounded to a integer. |
459 | Return nonzero if the operation overflows. | |
6d716ca8 RS |
460 | UNS nonzero says do unsigned division. */ |
461 | ||
dbb5b3ce | 462 | int |
6d716ca8 RS |
463 | div_and_round_double (code, uns, |
464 | lnum_orig, hnum_orig, lden_orig, hden_orig, | |
465 | lquo, hquo, lrem, hrem) | |
466 | enum tree_code code; | |
467 | int uns; | |
906c4e36 RK |
468 | HOST_WIDE_INT lnum_orig, hnum_orig; /* num == numerator == dividend */ |
469 | HOST_WIDE_INT lden_orig, hden_orig; /* den == denominator == divisor */ | |
470 | HOST_WIDE_INT *lquo, *hquo, *lrem, *hrem; | |
6d716ca8 RS |
471 | { |
472 | int quo_neg = 0; | |
37bdb7e3 TG |
473 | HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */ |
474 | HOST_WIDE_INT den[4], quo[4]; | |
475 | register int i, j; | |
476 | unsigned HOST_WIDE_INT work; | |
10fa1ee2 | 477 | register unsigned HOST_WIDE_INT carry = 0; |
88ee2651 | 478 | HOST_WIDE_INT lnum = lnum_orig; |
b8eb43a2 | 479 | HOST_WIDE_INT hnum = hnum_orig; |
88ee2651 | 480 | HOST_WIDE_INT lden = lden_orig; |
b8eb43a2 | 481 | HOST_WIDE_INT hden = hden_orig; |
fe3e8e40 | 482 | int overflow = 0; |
6d716ca8 RS |
483 | |
484 | if ((hden == 0) && (lden == 0)) | |
956d6950 | 485 | overflow = 1, lden = 1; |
6d716ca8 RS |
486 | |
487 | /* calculate quotient sign and convert operands to unsigned. */ | |
488 | if (!uns) | |
489 | { | |
fe3e8e40 | 490 | if (hnum < 0) |
6d716ca8 RS |
491 | { |
492 | quo_neg = ~ quo_neg; | |
fe3e8e40 RS |
493 | /* (minimum integer) / (-1) is the only overflow case. */ |
494 | if (neg_double (lnum, hnum, &lnum, &hnum) && (lden & hden) == -1) | |
495 | overflow = 1; | |
6d716ca8 | 496 | } |
fe3e8e40 | 497 | if (hden < 0) |
6d716ca8 RS |
498 | { |
499 | quo_neg = ~ quo_neg; | |
fe3e8e40 | 500 | neg_double (lden, hden, &lden, &hden); |
6d716ca8 RS |
501 | } |
502 | } | |
503 | ||
504 | if (hnum == 0 && hden == 0) | |
505 | { /* single precision */ | |
506 | *hquo = *hrem = 0; | |
88ee2651 RK |
507 | /* This unsigned division rounds toward zero. */ |
508 | *lquo = lnum / (unsigned HOST_WIDE_INT) lden; | |
6d716ca8 RS |
509 | goto finish_up; |
510 | } | |
511 | ||
512 | if (hnum == 0) | |
513 | { /* trivial case: dividend < divisor */ | |
514 | /* hden != 0 already checked. */ | |
515 | *hquo = *lquo = 0; | |
516 | *hrem = hnum; | |
517 | *lrem = lnum; | |
518 | goto finish_up; | |
519 | } | |
520 | ||
4c9a05bc | 521 | bzero ((char *) quo, sizeof quo); |
6d716ca8 | 522 | |
4c9a05bc RK |
523 | bzero ((char *) num, sizeof num); /* to zero 9th element */ |
524 | bzero ((char *) den, sizeof den); | |
6d716ca8 RS |
525 | |
526 | encode (num, lnum, hnum); | |
527 | encode (den, lden, hden); | |
528 | ||
37bdb7e3 TG |
529 | /* Special code for when the divisor < BASE. */ |
530 | if (hden == 0 && lden < BASE) | |
531 | { | |
6d716ca8 | 532 | /* hnum != 0 already checked. */ |
37bdb7e3 | 533 | for (i = 4 - 1; i >= 0; i--) |
6d716ca8 | 534 | { |
37bdb7e3 | 535 | work = num[i] + carry * BASE; |
88ee2651 RK |
536 | quo[i] = work / (unsigned HOST_WIDE_INT) lden; |
537 | carry = work % (unsigned HOST_WIDE_INT) lden; | |
6d716ca8 RS |
538 | } |
539 | } | |
37bdb7e3 TG |
540 | else |
541 | { | |
542 | /* Full double precision division, | |
543 | with thanks to Don Knuth's "Seminumerical Algorithms". */ | |
10fa1ee2 RK |
544 | int num_hi_sig, den_hi_sig; |
545 | unsigned HOST_WIDE_INT quo_est, scale; | |
6d716ca8 RS |
546 | |
547 | /* Find the highest non-zero divisor digit. */ | |
37bdb7e3 | 548 | for (i = 4 - 1; ; i--) |
6d716ca8 RS |
549 | if (den[i] != 0) { |
550 | den_hi_sig = i; | |
551 | break; | |
552 | } | |
6d716ca8 RS |
553 | |
554 | /* Insure that the first digit of the divisor is at least BASE/2. | |
555 | This is required by the quotient digit estimation algorithm. */ | |
556 | ||
557 | scale = BASE / (den[den_hi_sig] + 1); | |
558 | if (scale > 1) { /* scale divisor and dividend */ | |
559 | carry = 0; | |
37bdb7e3 | 560 | for (i = 0; i <= 4 - 1; i++) { |
6d716ca8 | 561 | work = (num[i] * scale) + carry; |
37bdb7e3 TG |
562 | num[i] = LOWPART (work); |
563 | carry = HIGHPART (work); | |
564 | } num[4] = carry; | |
6d716ca8 | 565 | carry = 0; |
37bdb7e3 | 566 | for (i = 0; i <= 4 - 1; i++) { |
6d716ca8 | 567 | work = (den[i] * scale) + carry; |
37bdb7e3 TG |
568 | den[i] = LOWPART (work); |
569 | carry = HIGHPART (work); | |
6d716ca8 RS |
570 | if (den[i] != 0) den_hi_sig = i; |
571 | } | |
572 | } | |
573 | ||
37bdb7e3 TG |
574 | num_hi_sig = 4; |
575 | ||
6d716ca8 | 576 | /* Main loop */ |
37bdb7e3 | 577 | for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--) { |
6dc42e49 | 578 | /* guess the next quotient digit, quo_est, by dividing the first |
6d716ca8 RS |
579 | two remaining dividend digits by the high order quotient digit. |
580 | quo_est is never low and is at most 2 high. */ | |
37bdb7e3 | 581 | unsigned HOST_WIDE_INT tmp; |
6d716ca8 | 582 | |
37bdb7e3 TG |
583 | num_hi_sig = i + den_hi_sig + 1; |
584 | work = num[num_hi_sig] * BASE + num[num_hi_sig - 1]; | |
585 | if (num[num_hi_sig] != den[den_hi_sig]) | |
6d716ca8 | 586 | quo_est = work / den[den_hi_sig]; |
37bdb7e3 | 587 | else |
6d716ca8 | 588 | quo_est = BASE - 1; |
6d716ca8 RS |
589 | |
590 | /* refine quo_est so it's usually correct, and at most one high. */ | |
37bdb7e3 TG |
591 | tmp = work - quo_est * den[den_hi_sig]; |
592 | if (tmp < BASE | |
593 | && den[den_hi_sig - 1] * quo_est > (tmp * BASE + num[num_hi_sig - 2])) | |
6d716ca8 RS |
594 | quo_est--; |
595 | ||
596 | /* Try QUO_EST as the quotient digit, by multiplying the | |
597 | divisor by QUO_EST and subtracting from the remaining dividend. | |
598 | Keep in mind that QUO_EST is the I - 1st digit. */ | |
599 | ||
600 | carry = 0; | |
6d716ca8 RS |
601 | for (j = 0; j <= den_hi_sig; j++) |
602 | { | |
37bdb7e3 TG |
603 | work = quo_est * den[j] + carry; |
604 | carry = HIGHPART (work); | |
605 | work = num[i + j] - LOWPART (work); | |
606 | num[i + j] = LOWPART (work); | |
607 | carry += HIGHPART (work) != 0; | |
6d716ca8 RS |
608 | } |
609 | ||
610 | /* if quo_est was high by one, then num[i] went negative and | |
611 | we need to correct things. */ | |
612 | ||
37bdb7e3 | 613 | if (num[num_hi_sig] < carry) |
6d716ca8 RS |
614 | { |
615 | quo_est--; | |
616 | carry = 0; /* add divisor back in */ | |
617 | for (j = 0; j <= den_hi_sig; j++) | |
618 | { | |
37bdb7e3 TG |
619 | work = num[i + j] + den[j] + carry; |
620 | carry = HIGHPART (work); | |
621 | num[i + j] = LOWPART (work); | |
6d716ca8 | 622 | } |
37bdb7e3 | 623 | num [num_hi_sig] += carry; |
6d716ca8 RS |
624 | } |
625 | ||
626 | /* store the quotient digit. */ | |
37bdb7e3 | 627 | quo[i] = quo_est; |
6d716ca8 RS |
628 | } |
629 | } | |
630 | ||
631 | decode (quo, lquo, hquo); | |
632 | ||
633 | finish_up: | |
634 | /* if result is negative, make it so. */ | |
635 | if (quo_neg) | |
636 | neg_double (*lquo, *hquo, lquo, hquo); | |
637 | ||
638 | /* compute trial remainder: rem = num - (quo * den) */ | |
639 | mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem); | |
640 | neg_double (*lrem, *hrem, lrem, hrem); | |
641 | add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem); | |
642 | ||
643 | switch (code) | |
644 | { | |
645 | case TRUNC_DIV_EXPR: | |
646 | case TRUNC_MOD_EXPR: /* round toward zero */ | |
647 | case EXACT_DIV_EXPR: /* for this one, it shouldn't matter */ | |
fe3e8e40 | 648 | return overflow; |
6d716ca8 RS |
649 | |
650 | case FLOOR_DIV_EXPR: | |
651 | case FLOOR_MOD_EXPR: /* round toward negative infinity */ | |
652 | if (quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio < 0 && rem != 0 */ | |
653 | { | |
654 | /* quo = quo - 1; */ | |
906c4e36 RK |
655 | add_double (*lquo, *hquo, (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, |
656 | lquo, hquo); | |
6d716ca8 | 657 | } |
fe3e8e40 | 658 | else return overflow; |
6d716ca8 RS |
659 | break; |
660 | ||
661 | case CEIL_DIV_EXPR: | |
662 | case CEIL_MOD_EXPR: /* round toward positive infinity */ | |
663 | if (!quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio > 0 && rem != 0 */ | |
664 | { | |
906c4e36 RK |
665 | add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0, |
666 | lquo, hquo); | |
6d716ca8 | 667 | } |
fe3e8e40 | 668 | else return overflow; |
6d716ca8 RS |
669 | break; |
670 | ||
671 | case ROUND_DIV_EXPR: | |
672 | case ROUND_MOD_EXPR: /* round to closest integer */ | |
673 | { | |
906c4e36 RK |
674 | HOST_WIDE_INT labs_rem = *lrem, habs_rem = *hrem; |
675 | HOST_WIDE_INT labs_den = lden, habs_den = hden, ltwice, htwice; | |
6d716ca8 RS |
676 | |
677 | /* get absolute values */ | |
678 | if (*hrem < 0) neg_double (*lrem, *hrem, &labs_rem, &habs_rem); | |
679 | if (hden < 0) neg_double (lden, hden, &labs_den, &habs_den); | |
680 | ||
681 | /* if (2 * abs (lrem) >= abs (lden)) */ | |
906c4e36 RK |
682 | mul_double ((HOST_WIDE_INT) 2, (HOST_WIDE_INT) 0, |
683 | labs_rem, habs_rem, <wice, &htwice); | |
684 | if (((unsigned HOST_WIDE_INT) habs_den | |
685 | < (unsigned HOST_WIDE_INT) htwice) | |
686 | || (((unsigned HOST_WIDE_INT) habs_den | |
687 | == (unsigned HOST_WIDE_INT) htwice) | |
688 | && ((HOST_WIDE_INT unsigned) labs_den | |
689 | < (unsigned HOST_WIDE_INT) ltwice))) | |
6d716ca8 RS |
690 | { |
691 | if (*hquo < 0) | |
692 | /* quo = quo - 1; */ | |
906c4e36 RK |
693 | add_double (*lquo, *hquo, |
694 | (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, lquo, hquo); | |
6d716ca8 RS |
695 | else |
696 | /* quo = quo + 1; */ | |
906c4e36 RK |
697 | add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0, |
698 | lquo, hquo); | |
6d716ca8 | 699 | } |
fe3e8e40 | 700 | else return overflow; |
6d716ca8 RS |
701 | } |
702 | break; | |
703 | ||
704 | default: | |
705 | abort (); | |
706 | } | |
707 | ||
708 | /* compute true remainder: rem = num - (quo * den) */ | |
709 | mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem); | |
710 | neg_double (*lrem, *hrem, lrem, hrem); | |
711 | add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem); | |
fe3e8e40 | 712 | return overflow; |
6d716ca8 RS |
713 | } |
714 | \f | |
5008b8ae | 715 | #ifndef REAL_ARITHMETIC |
649ff3b4 RK |
716 | /* Effectively truncate a real value to represent the nearest possible value |
717 | in a narrower mode. The result is actually represented in the same data | |
718 | type as the argument, but its value is usually different. | |
719 | ||
720 | A trap may occur during the FP operations and it is the responsibility | |
721 | of the calling function to have a handler established. */ | |
5352b11a RS |
722 | |
723 | REAL_VALUE_TYPE | |
724 | real_value_truncate (mode, arg) | |
725 | enum machine_mode mode; | |
726 | REAL_VALUE_TYPE arg; | |
727 | { | |
649ff3b4 | 728 | return REAL_VALUE_TRUNCATE (mode, arg); |
5352b11a RS |
729 | } |
730 | ||
6d716ca8 RS |
731 | #if TARGET_FLOAT_FORMAT == IEEE_FLOAT_FORMAT |
732 | ||
733 | /* Check for infinity in an IEEE double precision number. */ | |
734 | ||
735 | int | |
736 | target_isinf (x) | |
737 | REAL_VALUE_TYPE x; | |
738 | { | |
739 | /* The IEEE 64-bit double format. */ | |
740 | union { | |
741 | REAL_VALUE_TYPE d; | |
742 | struct { | |
743 | unsigned sign : 1; | |
744 | unsigned exponent : 11; | |
745 | unsigned mantissa1 : 20; | |
746 | unsigned mantissa2; | |
747 | } little_endian; | |
748 | struct { | |
749 | unsigned mantissa2; | |
750 | unsigned mantissa1 : 20; | |
751 | unsigned exponent : 11; | |
752 | unsigned sign : 1; | |
753 | } big_endian; | |
754 | } u; | |
755 | ||
756 | u.d = dconstm1; | |
757 | if (u.big_endian.sign == 1) | |
758 | { | |
759 | u.d = x; | |
760 | return (u.big_endian.exponent == 2047 | |
761 | && u.big_endian.mantissa1 == 0 | |
762 | && u.big_endian.mantissa2 == 0); | |
763 | } | |
764 | else | |
765 | { | |
766 | u.d = x; | |
767 | return (u.little_endian.exponent == 2047 | |
768 | && u.little_endian.mantissa1 == 0 | |
769 | && u.little_endian.mantissa2 == 0); | |
770 | } | |
771 | } | |
772 | ||
7d4d4d22 RS |
773 | /* Check whether an IEEE double precision number is a NaN. */ |
774 | ||
775 | int | |
776 | target_isnan (x) | |
777 | REAL_VALUE_TYPE x; | |
778 | { | |
779 | /* The IEEE 64-bit double format. */ | |
780 | union { | |
781 | REAL_VALUE_TYPE d; | |
782 | struct { | |
783 | unsigned sign : 1; | |
784 | unsigned exponent : 11; | |
785 | unsigned mantissa1 : 20; | |
786 | unsigned mantissa2; | |
787 | } little_endian; | |
788 | struct { | |
789 | unsigned mantissa2; | |
790 | unsigned mantissa1 : 20; | |
791 | unsigned exponent : 11; | |
792 | unsigned sign : 1; | |
793 | } big_endian; | |
794 | } u; | |
795 | ||
796 | u.d = dconstm1; | |
797 | if (u.big_endian.sign == 1) | |
798 | { | |
799 | u.d = x; | |
800 | return (u.big_endian.exponent == 2047 | |
801 | && (u.big_endian.mantissa1 != 0 | |
802 | || u.big_endian.mantissa2 != 0)); | |
803 | } | |
804 | else | |
805 | { | |
806 | u.d = x; | |
807 | return (u.little_endian.exponent == 2047 | |
808 | && (u.little_endian.mantissa1 != 0 | |
809 | || u.little_endian.mantissa2 != 0)); | |
810 | } | |
811 | } | |
812 | ||
c05a9b68 | 813 | /* Check for a negative IEEE double precision number. */ |
6d716ca8 RS |
814 | |
815 | int | |
c05a9b68 | 816 | target_negative (x) |
6d716ca8 RS |
817 | REAL_VALUE_TYPE x; |
818 | { | |
c05a9b68 RS |
819 | /* The IEEE 64-bit double format. */ |
820 | union { | |
821 | REAL_VALUE_TYPE d; | |
822 | struct { | |
823 | unsigned sign : 1; | |
824 | unsigned exponent : 11; | |
825 | unsigned mantissa1 : 20; | |
826 | unsigned mantissa2; | |
827 | } little_endian; | |
828 | struct { | |
829 | unsigned mantissa2; | |
830 | unsigned mantissa1 : 20; | |
831 | unsigned exponent : 11; | |
832 | unsigned sign : 1; | |
833 | } big_endian; | |
834 | } u; | |
6d716ca8 | 835 | |
c05a9b68 RS |
836 | u.d = dconstm1; |
837 | if (u.big_endian.sign == 1) | |
838 | { | |
839 | u.d = x; | |
840 | return u.big_endian.sign; | |
841 | } | |
842 | else | |
843 | { | |
844 | u.d = x; | |
845 | return u.little_endian.sign; | |
846 | } | |
6d716ca8 RS |
847 | } |
848 | #else /* Target not IEEE */ | |
849 | ||
850 | /* Let's assume other float formats don't have infinity. | |
851 | (This can be overridden by redefining REAL_VALUE_ISINF.) */ | |
852 | ||
853 | target_isinf (x) | |
854 | REAL_VALUE_TYPE x; | |
855 | { | |
856 | return 0; | |
857 | } | |
858 | ||
7d4d4d22 RS |
859 | /* Let's assume other float formats don't have NaNs. |
860 | (This can be overridden by redefining REAL_VALUE_ISNAN.) */ | |
861 | ||
862 | target_isnan (x) | |
863 | REAL_VALUE_TYPE x; | |
864 | { | |
865 | return 0; | |
866 | } | |
867 | ||
6d716ca8 | 868 | /* Let's assume other float formats don't have minus zero. |
c05a9b68 | 869 | (This can be overridden by redefining REAL_VALUE_NEGATIVE.) */ |
6d716ca8 | 870 | |
c05a9b68 | 871 | target_negative (x) |
6d716ca8 RS |
872 | REAL_VALUE_TYPE x; |
873 | { | |
c05a9b68 | 874 | return x < 0; |
6d716ca8 RS |
875 | } |
876 | #endif /* Target not IEEE */ | |
39647dcb RK |
877 | |
878 | /* Try to change R into its exact multiplicative inverse in machine mode | |
879 | MODE. Return nonzero function value if successful. */ | |
880 | ||
881 | int | |
882 | exact_real_inverse (mode, r) | |
883 | enum machine_mode mode; | |
884 | REAL_VALUE_TYPE *r; | |
885 | { | |
886 | union | |
887 | { | |
888 | double d; | |
889 | unsigned short i[4]; | |
890 | }x, t, y; | |
891 | int i; | |
892 | ||
893 | /* Usually disable if bounds checks are not reliable. */ | |
894 | if ((HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT) && !flag_pretend_float) | |
895 | return 0; | |
896 | ||
897 | /* Set array index to the less significant bits in the unions, depending | |
898 | on the endian-ness of the host doubles. | |
899 | Disable if insufficient information on the data structure. */ | |
900 | #if HOST_FLOAT_FORMAT == UNKNOWN_FLOAT_FORMAT | |
901 | return 0; | |
902 | #else | |
903 | #if HOST_FLOAT_FORMAT == VAX_FLOAT_FORMAT | |
904 | #define K 2 | |
905 | #else | |
906 | #if HOST_FLOAT_FORMAT == IBM_FLOAT_FORMAT | |
907 | #define K 2 | |
908 | #else | |
909 | #define K (2 * HOST_FLOAT_WORDS_BIG_ENDIAN) | |
910 | #endif | |
911 | #endif | |
912 | #endif | |
913 | ||
914 | if (setjmp (float_error)) | |
915 | { | |
916 | /* Don't do the optimization if there was an arithmetic error. */ | |
917 | fail: | |
918 | set_float_handler (NULL_PTR); | |
919 | return 0; | |
920 | } | |
921 | set_float_handler (float_error); | |
922 | ||
923 | /* Domain check the argument. */ | |
924 | x.d = *r; | |
925 | if (x.d == 0.0) | |
926 | goto fail; | |
927 | ||
928 | #ifdef REAL_INFINITY | |
929 | if (REAL_VALUE_ISINF (x.d) || REAL_VALUE_ISNAN (x.d)) | |
930 | goto fail; | |
931 | #endif | |
932 | ||
933 | /* Compute the reciprocal and check for numerical exactness. | |
934 | It is unnecessary to check all the significand bits to determine | |
935 | whether X is a power of 2. If X is not, then it is impossible for | |
936 | the bottom half significand of both X and 1/X to be all zero bits. | |
937 | Hence we ignore the data structure of the top half and examine only | |
938 | the low order bits of the two significands. */ | |
939 | t.d = 1.0 / x.d; | |
940 | if (x.i[K] != 0 || x.i[K + 1] != 0 || t.i[K] != 0 || t.i[K + 1] != 0) | |
941 | goto fail; | |
942 | ||
943 | /* Truncate to the required mode and range-check the result. */ | |
944 | y.d = REAL_VALUE_TRUNCATE (mode, t.d); | |
945 | #ifdef CHECK_FLOAT_VALUE | |
946 | i = 0; | |
947 | if (CHECK_FLOAT_VALUE (mode, y.d, i)) | |
948 | goto fail; | |
949 | #endif | |
950 | ||
951 | /* Fail if truncation changed the value. */ | |
952 | if (y.d != t.d || y.d == 0.0) | |
953 | goto fail; | |
954 | ||
955 | #ifdef REAL_INFINITY | |
956 | if (REAL_VALUE_ISINF (y.d) || REAL_VALUE_ISNAN (y.d)) | |
957 | goto fail; | |
958 | #endif | |
959 | ||
960 | /* Output the reciprocal and return success flag. */ | |
961 | set_float_handler (NULL_PTR); | |
962 | *r = y.d; | |
963 | return 1; | |
964 | } | |
5008b8ae | 965 | #endif /* no REAL_ARITHMETIC */ |
6d716ca8 RS |
966 | \f |
967 | /* Split a tree IN into a constant and a variable part | |
968 | that could be combined with CODE to make IN. | |
969 | CODE must be a commutative arithmetic operation. | |
970 | Store the constant part into *CONP and the variable in &VARP. | |
971 | Return 1 if this was done; zero means the tree IN did not decompose | |
972 | this way. | |
973 | ||
974 | If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. | |
975 | Therefore, we must tell the caller whether the variable part | |
976 | was subtracted. We do this by storing 1 or -1 into *VARSIGNP. | |
977 | The value stored is the coefficient for the variable term. | |
978 | The constant term we return should always be added; | |
979 | we negate it if necessary. */ | |
980 | ||
981 | static int | |
982 | split_tree (in, code, varp, conp, varsignp) | |
983 | tree in; | |
984 | enum tree_code code; | |
985 | tree *varp, *conp; | |
986 | int *varsignp; | |
987 | { | |
988 | register tree outtype = TREE_TYPE (in); | |
989 | *varp = 0; | |
990 | *conp = 0; | |
991 | ||
992 | /* Strip any conversions that don't change the machine mode. */ | |
993 | while ((TREE_CODE (in) == NOP_EXPR | |
994 | || TREE_CODE (in) == CONVERT_EXPR) | |
995 | && (TYPE_MODE (TREE_TYPE (in)) | |
996 | == TYPE_MODE (TREE_TYPE (TREE_OPERAND (in, 0))))) | |
997 | in = TREE_OPERAND (in, 0); | |
998 | ||
999 | if (TREE_CODE (in) == code | |
7178e3af | 1000 | || (! FLOAT_TYPE_P (TREE_TYPE (in)) |
6d716ca8 RS |
1001 | /* We can associate addition and subtraction together |
1002 | (even though the C standard doesn't say so) | |
1003 | for integers because the value is not affected. | |
1004 | For reals, the value might be affected, so we can't. */ | |
7178e3af RK |
1005 | && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR) |
1006 | || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR)))) | |
6d716ca8 RS |
1007 | { |
1008 | enum tree_code code = TREE_CODE (TREE_OPERAND (in, 0)); | |
1009 | if (code == INTEGER_CST) | |
1010 | { | |
1011 | *conp = TREE_OPERAND (in, 0); | |
1012 | *varp = TREE_OPERAND (in, 1); | |
1013 | if (TYPE_MODE (TREE_TYPE (*varp)) != TYPE_MODE (outtype) | |
1014 | && TREE_TYPE (*varp) != outtype) | |
1015 | *varp = convert (outtype, *varp); | |
1016 | *varsignp = (TREE_CODE (in) == MINUS_EXPR) ? -1 : 1; | |
1017 | return 1; | |
1018 | } | |
1019 | if (TREE_CONSTANT (TREE_OPERAND (in, 1))) | |
1020 | { | |
1021 | *conp = TREE_OPERAND (in, 1); | |
1022 | *varp = TREE_OPERAND (in, 0); | |
1023 | *varsignp = 1; | |
1024 | if (TYPE_MODE (TREE_TYPE (*varp)) != TYPE_MODE (outtype) | |
1025 | && TREE_TYPE (*varp) != outtype) | |
1026 | *varp = convert (outtype, *varp); | |
1027 | if (TREE_CODE (in) == MINUS_EXPR) | |
1028 | { | |
1029 | /* If operation is subtraction and constant is second, | |
1030 | must negate it to get an additive constant. | |
1031 | And this cannot be done unless it is a manifest constant. | |
1032 | It could also be the address of a static variable. | |
1033 | We cannot negate that, so give up. */ | |
1034 | if (TREE_CODE (*conp) == INTEGER_CST) | |
1035 | /* Subtracting from integer_zero_node loses for long long. */ | |
1036 | *conp = fold (build1 (NEGATE_EXPR, TREE_TYPE (*conp), *conp)); | |
1037 | else | |
1038 | return 0; | |
1039 | } | |
1040 | return 1; | |
1041 | } | |
1042 | if (TREE_CONSTANT (TREE_OPERAND (in, 0))) | |
1043 | { | |
1044 | *conp = TREE_OPERAND (in, 0); | |
1045 | *varp = TREE_OPERAND (in, 1); | |
1046 | if (TYPE_MODE (TREE_TYPE (*varp)) != TYPE_MODE (outtype) | |
1047 | && TREE_TYPE (*varp) != outtype) | |
1048 | *varp = convert (outtype, *varp); | |
1049 | *varsignp = (TREE_CODE (in) == MINUS_EXPR) ? -1 : 1; | |
1050 | return 1; | |
1051 | } | |
1052 | } | |
1053 | return 0; | |
1054 | } | |
1055 | \f | |
e9a25f70 | 1056 | /* Combine two integer constants ARG1 and ARG2 under operation CODE |
6d716ca8 | 1057 | to produce a new constant. |
91d33e36 | 1058 | |
e9a25f70 JL |
1059 | If NOTRUNC is nonzero, do not truncate the result to fit the data type. |
1060 | If FORSIZE is nonzero, compute overflow for unsigned types. */ | |
6d716ca8 | 1061 | |
6d716ca8 | 1062 | static tree |
e9a25f70 | 1063 | int_const_binop (code, arg1, arg2, notrunc, forsize) |
6d716ca8 RS |
1064 | enum tree_code code; |
1065 | register tree arg1, arg2; | |
e9a25f70 | 1066 | int notrunc, forsize; |
6d716ca8 | 1067 | { |
e9a25f70 JL |
1068 | HOST_WIDE_INT int1l, int1h, int2l, int2h; |
1069 | HOST_WIDE_INT low, hi; | |
1070 | HOST_WIDE_INT garbagel, garbageh; | |
1071 | register tree t; | |
1072 | int uns = TREE_UNSIGNED (TREE_TYPE (arg1)); | |
1073 | int overflow = 0; | |
1074 | int no_overflow = 0; | |
3dedc65a | 1075 | |
e9a25f70 JL |
1076 | int1l = TREE_INT_CST_LOW (arg1); |
1077 | int1h = TREE_INT_CST_HIGH (arg1); | |
1078 | int2l = TREE_INT_CST_LOW (arg2); | |
1079 | int2h = TREE_INT_CST_HIGH (arg2); | |
1080 | ||
1081 | switch (code) | |
6d716ca8 | 1082 | { |
e9a25f70 JL |
1083 | case BIT_IOR_EXPR: |
1084 | low = int1l | int2l, hi = int1h | int2h; | |
1085 | break; | |
6d716ca8 | 1086 | |
e9a25f70 JL |
1087 | case BIT_XOR_EXPR: |
1088 | low = int1l ^ int2l, hi = int1h ^ int2h; | |
1089 | break; | |
6d716ca8 | 1090 | |
e9a25f70 JL |
1091 | case BIT_AND_EXPR: |
1092 | low = int1l & int2l, hi = int1h & int2h; | |
1093 | break; | |
6d716ca8 | 1094 | |
e9a25f70 JL |
1095 | case BIT_ANDTC_EXPR: |
1096 | low = int1l & ~int2l, hi = int1h & ~int2h; | |
1097 | break; | |
6d716ca8 | 1098 | |
e9a25f70 JL |
1099 | case RSHIFT_EXPR: |
1100 | int2l = - int2l; | |
1101 | case LSHIFT_EXPR: | |
1102 | /* It's unclear from the C standard whether shifts can overflow. | |
1103 | The following code ignores overflow; perhaps a C standard | |
1104 | interpretation ruling is needed. */ | |
1105 | lshift_double (int1l, int1h, int2l, | |
1106 | TYPE_PRECISION (TREE_TYPE (arg1)), | |
1107 | &low, &hi, | |
1108 | !uns); | |
1109 | no_overflow = 1; | |
1110 | break; | |
6d716ca8 | 1111 | |
e9a25f70 JL |
1112 | case RROTATE_EXPR: |
1113 | int2l = - int2l; | |
1114 | case LROTATE_EXPR: | |
1115 | lrotate_double (int1l, int1h, int2l, | |
1116 | TYPE_PRECISION (TREE_TYPE (arg1)), | |
1117 | &low, &hi); | |
1118 | break; | |
6d716ca8 | 1119 | |
e9a25f70 JL |
1120 | case PLUS_EXPR: |
1121 | overflow = add_double (int1l, int1h, int2l, int2h, &low, &hi); | |
1122 | break; | |
6d716ca8 | 1123 | |
e9a25f70 JL |
1124 | case MINUS_EXPR: |
1125 | neg_double (int2l, int2h, &low, &hi); | |
1126 | add_double (int1l, int1h, low, hi, &low, &hi); | |
1127 | overflow = overflow_sum_sign (hi, int2h, int1h); | |
1128 | break; | |
6d716ca8 | 1129 | |
e9a25f70 JL |
1130 | case MULT_EXPR: |
1131 | overflow = mul_double (int1l, int1h, int2l, int2h, &low, &hi); | |
1132 | break; | |
6d716ca8 | 1133 | |
e9a25f70 JL |
1134 | case TRUNC_DIV_EXPR: |
1135 | case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR: | |
1136 | case EXACT_DIV_EXPR: | |
1137 | /* This is a shortcut for a common special case. */ | |
1138 | if (int2h == 0 && int2l > 0 | |
1139 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
1140 | && ! TREE_CONSTANT_OVERFLOW (arg2) | |
1141 | && int1h == 0 && int1l >= 0) | |
1142 | { | |
1143 | if (code == CEIL_DIV_EXPR) | |
1144 | int1l += int2l - 1; | |
1145 | low = int1l / int2l, hi = 0; | |
6d716ca8 | 1146 | break; |
e9a25f70 | 1147 | } |
6d716ca8 | 1148 | |
e9a25f70 | 1149 | /* ... fall through ... */ |
6d716ca8 | 1150 | |
e9a25f70 JL |
1151 | case ROUND_DIV_EXPR: |
1152 | if (int2h == 0 && int2l == 1) | |
1153 | { | |
1154 | low = int1l, hi = int1h; | |
6d716ca8 | 1155 | break; |
e9a25f70 JL |
1156 | } |
1157 | if (int1l == int2l && int1h == int2h | |
1158 | && ! (int1l == 0 && int1h == 0)) | |
1159 | { | |
1160 | low = 1, hi = 0; | |
63e7fe9b | 1161 | break; |
e9a25f70 JL |
1162 | } |
1163 | overflow = div_and_round_double (code, uns, | |
1164 | int1l, int1h, int2l, int2h, | |
1165 | &low, &hi, &garbagel, &garbageh); | |
1166 | break; | |
63e7fe9b | 1167 | |
e9a25f70 JL |
1168 | case TRUNC_MOD_EXPR: |
1169 | case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR: | |
1170 | /* This is a shortcut for a common special case. */ | |
1171 | if (int2h == 0 && int2l > 0 | |
1172 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
1173 | && ! TREE_CONSTANT_OVERFLOW (arg2) | |
1174 | && int1h == 0 && int1l >= 0) | |
1175 | { | |
1176 | if (code == CEIL_MOD_EXPR) | |
1177 | int1l += int2l - 1; | |
1178 | low = int1l % int2l, hi = 0; | |
63e7fe9b | 1179 | break; |
e9a25f70 | 1180 | } |
63e7fe9b | 1181 | |
e9a25f70 JL |
1182 | /* ... fall through ... */ |
1183 | ||
1184 | case ROUND_MOD_EXPR: | |
1185 | overflow = div_and_round_double (code, uns, | |
1186 | int1l, int1h, int2l, int2h, | |
1187 | &garbagel, &garbageh, &low, &hi); | |
1188 | break; | |
1189 | ||
1190 | case MIN_EXPR: | |
1191 | case MAX_EXPR: | |
1192 | if (uns) | |
1193 | { | |
1194 | low = (((unsigned HOST_WIDE_INT) int1h | |
1195 | < (unsigned HOST_WIDE_INT) int2h) | |
1196 | || (((unsigned HOST_WIDE_INT) int1h | |
1197 | == (unsigned HOST_WIDE_INT) int2h) | |
1198 | && ((unsigned HOST_WIDE_INT) int1l | |
1199 | < (unsigned HOST_WIDE_INT) int2l))); | |
6d716ca8 | 1200 | } |
380ff34a RK |
1201 | else |
1202 | { | |
e9a25f70 JL |
1203 | low = ((int1h < int2h) |
1204 | || ((int1h == int2h) | |
1205 | && ((unsigned HOST_WIDE_INT) int1l | |
1206 | < (unsigned HOST_WIDE_INT) int2l))); | |
380ff34a | 1207 | } |
e9a25f70 JL |
1208 | if (low == (code == MIN_EXPR)) |
1209 | low = int1l, hi = int1h; | |
1210 | else | |
1211 | low = int2l, hi = int2h; | |
1212 | break; | |
3dedc65a | 1213 | |
e9a25f70 JL |
1214 | default: |
1215 | abort (); | |
3dedc65a | 1216 | } |
e9a25f70 JL |
1217 | |
1218 | if (TREE_TYPE (arg1) == sizetype && hi == 0 | |
e1ee5cdc RH |
1219 | && low >= 0 |
1220 | && (TYPE_MAX_VALUE (sizetype) == NULL | |
1221 | || low <= TREE_INT_CST_LOW (TYPE_MAX_VALUE (sizetype))) | |
e9a25f70 JL |
1222 | && ! overflow |
1223 | && ! TREE_OVERFLOW (arg1) && ! TREE_OVERFLOW (arg2)) | |
1224 | t = size_int (low); | |
1225 | else | |
1226 | { | |
1227 | t = build_int_2 (low, hi); | |
1228 | TREE_TYPE (t) = TREE_TYPE (arg1); | |
1229 | } | |
1230 | ||
1231 | TREE_OVERFLOW (t) | |
1232 | = ((notrunc ? (!uns || forsize) && overflow | |
1233 | : force_fit_type (t, (!uns || forsize) && overflow) && ! no_overflow) | |
1234 | | TREE_OVERFLOW (arg1) | |
1235 | | TREE_OVERFLOW (arg2)); | |
1236 | /* If we're doing a size calculation, unsigned arithmetic does overflow. | |
1237 | So check if force_fit_type truncated the value. */ | |
1238 | if (forsize | |
1239 | && ! TREE_OVERFLOW (t) | |
1240 | && (TREE_INT_CST_HIGH (t) != hi | |
1241 | || TREE_INT_CST_LOW (t) != low)) | |
1242 | TREE_OVERFLOW (t) = 1; | |
1243 | TREE_CONSTANT_OVERFLOW (t) = (TREE_OVERFLOW (t) | |
1244 | | TREE_CONSTANT_OVERFLOW (arg1) | |
1245 | | TREE_CONSTANT_OVERFLOW (arg2)); | |
1246 | return t; | |
1247 | } | |
1248 | ||
1249 | /* Combine two constants ARG1 and ARG2 under operation CODE | |
1250 | to produce a new constant. | |
1251 | We assume ARG1 and ARG2 have the same data type, | |
1252 | or at least are the same kind of constant and the same machine mode. | |
1253 | ||
1254 | If NOTRUNC is nonzero, do not truncate the result to fit the data type. */ | |
1255 | ||
1256 | static tree | |
1257 | const_binop (code, arg1, arg2, notrunc) | |
1258 | enum tree_code code; | |
1259 | register tree arg1, arg2; | |
1260 | int notrunc; | |
1261 | { | |
1262 | STRIP_NOPS (arg1); STRIP_NOPS (arg2); | |
1263 | ||
1264 | if (TREE_CODE (arg1) == INTEGER_CST) | |
1265 | return int_const_binop (code, arg1, arg2, notrunc, 0); | |
1266 | ||
6d716ca8 RS |
1267 | #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) |
1268 | if (TREE_CODE (arg1) == REAL_CST) | |
1269 | { | |
79c844cd RK |
1270 | REAL_VALUE_TYPE d1; |
1271 | REAL_VALUE_TYPE d2; | |
649ff3b4 | 1272 | int overflow = 0; |
5008b8ae | 1273 | REAL_VALUE_TYPE value; |
7c7b029d | 1274 | tree t; |
6d716ca8 | 1275 | |
79c844cd RK |
1276 | d1 = TREE_REAL_CST (arg1); |
1277 | d2 = TREE_REAL_CST (arg2); | |
5f610074 RK |
1278 | |
1279 | /* If either operand is a NaN, just return it. Otherwise, set up | |
1280 | for floating-point trap; we return an overflow. */ | |
1281 | if (REAL_VALUE_ISNAN (d1)) | |
1282 | return arg1; | |
1283 | else if (REAL_VALUE_ISNAN (d2)) | |
1284 | return arg2; | |
1285 | else if (setjmp (float_error)) | |
6d716ca8 | 1286 | { |
649ff3b4 RK |
1287 | t = copy_node (arg1); |
1288 | overflow = 1; | |
1289 | goto got_float; | |
6d716ca8 | 1290 | } |
649ff3b4 | 1291 | |
7c7b029d | 1292 | set_float_handler (float_error); |
6d716ca8 RS |
1293 | |
1294 | #ifdef REAL_ARITHMETIC | |
1295 | REAL_ARITHMETIC (value, code, d1, d2); | |
1296 | #else | |
1297 | switch (code) | |
1298 | { | |
1299 | case PLUS_EXPR: | |
1300 | value = d1 + d2; | |
1301 | break; | |
1302 | ||
1303 | case MINUS_EXPR: | |
1304 | value = d1 - d2; | |
1305 | break; | |
1306 | ||
1307 | case MULT_EXPR: | |
1308 | value = d1 * d2; | |
1309 | break; | |
1310 | ||
1311 | case RDIV_EXPR: | |
1312 | #ifndef REAL_INFINITY | |
1313 | if (d2 == 0) | |
1314 | abort (); | |
1315 | #endif | |
1316 | ||
1317 | value = d1 / d2; | |
1318 | break; | |
1319 | ||
1320 | case MIN_EXPR: | |
1321 | value = MIN (d1, d2); | |
1322 | break; | |
1323 | ||
1324 | case MAX_EXPR: | |
1325 | value = MAX (d1, d2); | |
1326 | break; | |
1327 | ||
1328 | default: | |
1329 | abort (); | |
1330 | } | |
1331 | #endif /* no REAL_ARITHMETIC */ | |
7c7b029d | 1332 | t = build_real (TREE_TYPE (arg1), |
5352b11a | 1333 | real_value_truncate (TYPE_MODE (TREE_TYPE (arg1)), value)); |
649ff3b4 | 1334 | got_float: |
906c4e36 | 1335 | set_float_handler (NULL_PTR); |
649ff3b4 RK |
1336 | |
1337 | TREE_OVERFLOW (t) | |
1338 | = (force_fit_type (t, overflow) | |
1339 | | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2)); | |
1340 | TREE_CONSTANT_OVERFLOW (t) | |
1341 | = TREE_OVERFLOW (t) | |
1342 | | TREE_CONSTANT_OVERFLOW (arg1) | |
1343 | | TREE_CONSTANT_OVERFLOW (arg2); | |
7c7b029d | 1344 | return t; |
6d716ca8 RS |
1345 | } |
1346 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
1347 | if (TREE_CODE (arg1) == COMPLEX_CST) | |
1348 | { | |
214d5b84 | 1349 | register tree type = TREE_TYPE (arg1); |
6d716ca8 RS |
1350 | register tree r1 = TREE_REALPART (arg1); |
1351 | register tree i1 = TREE_IMAGPART (arg1); | |
1352 | register tree r2 = TREE_REALPART (arg2); | |
1353 | register tree i2 = TREE_IMAGPART (arg2); | |
1354 | register tree t; | |
1355 | ||
1356 | switch (code) | |
1357 | { | |
1358 | case PLUS_EXPR: | |
214d5b84 RK |
1359 | t = build_complex (type, |
1360 | const_binop (PLUS_EXPR, r1, r2, notrunc), | |
91d33e36 | 1361 | const_binop (PLUS_EXPR, i1, i2, notrunc)); |
6d716ca8 RS |
1362 | break; |
1363 | ||
1364 | case MINUS_EXPR: | |
214d5b84 RK |
1365 | t = build_complex (type, |
1366 | const_binop (MINUS_EXPR, r1, r2, notrunc), | |
91d33e36 | 1367 | const_binop (MINUS_EXPR, i1, i2, notrunc)); |
6d716ca8 RS |
1368 | break; |
1369 | ||
1370 | case MULT_EXPR: | |
214d5b84 RK |
1371 | t = build_complex (type, |
1372 | const_binop (MINUS_EXPR, | |
91d33e36 RS |
1373 | const_binop (MULT_EXPR, |
1374 | r1, r2, notrunc), | |
1375 | const_binop (MULT_EXPR, | |
1376 | i1, i2, notrunc), | |
1377 | notrunc), | |
6d716ca8 | 1378 | const_binop (PLUS_EXPR, |
91d33e36 RS |
1379 | const_binop (MULT_EXPR, |
1380 | r1, i2, notrunc), | |
1381 | const_binop (MULT_EXPR, | |
1382 | i1, r2, notrunc), | |
1383 | notrunc)); | |
6d716ca8 RS |
1384 | break; |
1385 | ||
1386 | case RDIV_EXPR: | |
1387 | { | |
1388 | register tree magsquared | |
1389 | = const_binop (PLUS_EXPR, | |
91d33e36 RS |
1390 | const_binop (MULT_EXPR, r2, r2, notrunc), |
1391 | const_binop (MULT_EXPR, i2, i2, notrunc), | |
1392 | notrunc); | |
58633be8 | 1393 | |
214d5b84 RK |
1394 | t = build_complex (type, |
1395 | const_binop | |
1396 | (INTEGRAL_TYPE_P (TREE_TYPE (r1)) | |
1397 | ? TRUNC_DIV_EXPR : RDIV_EXPR, | |
1398 | const_binop (PLUS_EXPR, | |
1399 | const_binop (MULT_EXPR, r1, r2, | |
1400 | notrunc), | |
1401 | const_binop (MULT_EXPR, i1, i2, | |
1402 | notrunc), | |
1403 | notrunc), | |
1404 | magsquared, notrunc), | |
1405 | const_binop | |
1406 | (INTEGRAL_TYPE_P (TREE_TYPE (r1)) | |
1407 | ? TRUNC_DIV_EXPR : RDIV_EXPR, | |
1408 | const_binop (MINUS_EXPR, | |
1409 | const_binop (MULT_EXPR, i1, r2, | |
1410 | notrunc), | |
1411 | const_binop (MULT_EXPR, r1, i2, | |
1412 | notrunc), | |
1413 | notrunc), | |
1414 | magsquared, notrunc)); | |
6d716ca8 RS |
1415 | } |
1416 | break; | |
1417 | ||
1418 | default: | |
1419 | abort (); | |
1420 | } | |
6d716ca8 RS |
1421 | return t; |
1422 | } | |
1423 | return 0; | |
1424 | } | |
1425 | \f | |
f8dac6eb R |
1426 | /* Return an INTEGER_CST with value V . The type is determined by bit_p: |
1427 | if it is zero, the type is taken from sizetype; if it is one, the type | |
1428 | is taken from bitsizetype. */ | |
6d716ca8 RS |
1429 | |
1430 | tree | |
f8dac6eb R |
1431 | size_int_wide (number, high, bit_p) |
1432 | unsigned HOST_WIDE_INT number, high; | |
2fde567e | 1433 | int bit_p; |
6d716ca8 RS |
1434 | { |
1435 | register tree t; | |
1436 | /* Type-size nodes already made for small sizes. */ | |
f8dac6eb | 1437 | static tree size_table[2*HOST_BITS_PER_WIDE_INT + 1][2]; |
6d716ca8 | 1438 | |
f8dac6eb R |
1439 | if (number < 2*HOST_BITS_PER_WIDE_INT + 1 && ! high |
1440 | && size_table[number][bit_p] != 0) | |
1441 | return size_table[number][bit_p]; | |
1442 | if (number < 2*HOST_BITS_PER_WIDE_INT + 1 && ! high) | |
6d716ca8 | 1443 | { |
6d716ca8 RS |
1444 | push_obstacks_nochange (); |
1445 | /* Make this a permanent node. */ | |
c05a9b68 | 1446 | end_temporary_allocation (); |
6d716ca8 | 1447 | t = build_int_2 (number, 0); |
896cced4 | 1448 | TREE_TYPE (t) = bit_p ? bitsizetype : sizetype; |
f8dac6eb | 1449 | size_table[number][bit_p] = t; |
6d716ca8 RS |
1450 | pop_obstacks (); |
1451 | } | |
1452 | else | |
1453 | { | |
f8dac6eb | 1454 | t = build_int_2 (number, high); |
896cced4 | 1455 | TREE_TYPE (t) = bit_p ? bitsizetype : sizetype; |
380ff34a | 1456 | TREE_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (t) = force_fit_type (t, 0); |
6d716ca8 RS |
1457 | } |
1458 | return t; | |
1459 | } | |
1460 | ||
1461 | /* Combine operands OP1 and OP2 with arithmetic operation CODE. | |
1462 | CODE is a tree code. Data type is taken from `sizetype', | |
1463 | If the operands are constant, so is the result. */ | |
1464 | ||
1465 | tree | |
1466 | size_binop (code, arg0, arg1) | |
1467 | enum tree_code code; | |
1468 | tree arg0, arg1; | |
1469 | { | |
1470 | /* Handle the special case of two integer constants faster. */ | |
1471 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) | |
1472 | { | |
1473 | /* And some specific cases even faster than that. */ | |
9898deac | 1474 | if (code == PLUS_EXPR && integer_zerop (arg0)) |
6d716ca8 | 1475 | return arg1; |
9898deac RK |
1476 | else if ((code == MINUS_EXPR || code == PLUS_EXPR) |
1477 | && integer_zerop (arg1)) | |
6d716ca8 | 1478 | return arg0; |
9898deac | 1479 | else if (code == MULT_EXPR && integer_onep (arg0)) |
6d716ca8 | 1480 | return arg1; |
9898deac | 1481 | |
6d716ca8 | 1482 | /* Handle general case of two integer constants. */ |
e9a25f70 | 1483 | return int_const_binop (code, arg0, arg1, 0, 1); |
6d716ca8 RS |
1484 | } |
1485 | ||
1486 | if (arg0 == error_mark_node || arg1 == error_mark_node) | |
1487 | return error_mark_node; | |
1488 | ||
1489 | return fold (build (code, sizetype, arg0, arg1)); | |
1490 | } | |
1491 | \f | |
1492 | /* Given T, a tree representing type conversion of ARG1, a constant, | |
1493 | return a constant tree representing the result of conversion. */ | |
1494 | ||
1495 | static tree | |
1496 | fold_convert (t, arg1) | |
1497 | register tree t; | |
1498 | register tree arg1; | |
1499 | { | |
1500 | register tree type = TREE_TYPE (t); | |
649ff3b4 | 1501 | int overflow = 0; |
6d716ca8 | 1502 | |
e5e809f4 | 1503 | if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)) |
6d716ca8 RS |
1504 | { |
1505 | if (TREE_CODE (arg1) == INTEGER_CST) | |
1506 | { | |
e3374525 RK |
1507 | /* If we would build a constant wider than GCC supports, |
1508 | leave the conversion unfolded. */ | |
1509 | if (TYPE_PRECISION (type) > 2 * HOST_BITS_PER_WIDE_INT) | |
1510 | return t; | |
1511 | ||
6d716ca8 RS |
1512 | /* Given an integer constant, make new constant with new type, |
1513 | appropriately sign-extended or truncated. */ | |
1514 | t = build_int_2 (TREE_INT_CST_LOW (arg1), | |
1515 | TREE_INT_CST_HIGH (arg1)); | |
1516 | TREE_TYPE (t) = type; | |
e0f776fb | 1517 | /* Indicate an overflow if (1) ARG1 already overflowed, |
dc3907c5 PE |
1518 | or (2) force_fit_type indicates an overflow. |
1519 | Tell force_fit_type that an overflow has already occurred | |
b472527b JL |
1520 | if ARG1 is a too-large unsigned value and T is signed. |
1521 | But don't indicate an overflow if converting a pointer. */ | |
dc3907c5 | 1522 | TREE_OVERFLOW (t) |
e5e809f4 JL |
1523 | = ((force_fit_type (t, |
1524 | (TREE_INT_CST_HIGH (arg1) < 0 | |
4f242db3 | 1525 | && (TREE_UNSIGNED (type) |
e5e809f4 JL |
1526 | < TREE_UNSIGNED (TREE_TYPE (arg1))))) |
1527 | && ! POINTER_TYPE_P (TREE_TYPE (arg1))) | |
1528 | || TREE_OVERFLOW (arg1)); | |
dc3907c5 PE |
1529 | TREE_CONSTANT_OVERFLOW (t) |
1530 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
6d716ca8 RS |
1531 | } |
1532 | #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) | |
1533 | else if (TREE_CODE (arg1) == REAL_CST) | |
1534 | { | |
4b8a0062 RK |
1535 | /* Don't initialize these, use assignments. |
1536 | Initialized local aggregates don't work on old compilers. */ | |
1537 | REAL_VALUE_TYPE x; | |
1538 | REAL_VALUE_TYPE l; | |
1539 | REAL_VALUE_TYPE u; | |
7cb6a121 | 1540 | tree type1 = TREE_TYPE (arg1); |
e1ee5cdc | 1541 | int no_upper_bound; |
4b8a0062 RK |
1542 | |
1543 | x = TREE_REAL_CST (arg1); | |
7cb6a121 | 1544 | l = real_value_from_int_cst (type1, TYPE_MIN_VALUE (type)); |
e1ee5cdc RH |
1545 | |
1546 | no_upper_bound = (TYPE_MAX_VALUE (type) == NULL); | |
1547 | if (!no_upper_bound) | |
1548 | u = real_value_from_int_cst (type1, TYPE_MAX_VALUE (type)); | |
1549 | ||
4b3d5ea0 RS |
1550 | /* See if X will be in range after truncation towards 0. |
1551 | To compensate for truncation, move the bounds away from 0, | |
1552 | but reject if X exactly equals the adjusted bounds. */ | |
1553 | #ifdef REAL_ARITHMETIC | |
1554 | REAL_ARITHMETIC (l, MINUS_EXPR, l, dconst1); | |
e1ee5cdc RH |
1555 | if (!no_upper_bound) |
1556 | REAL_ARITHMETIC (u, PLUS_EXPR, u, dconst1); | |
4b3d5ea0 RS |
1557 | #else |
1558 | l--; | |
e1ee5cdc RH |
1559 | if (!no_upper_bound) |
1560 | u++; | |
4b3d5ea0 | 1561 | #endif |
5f610074 RK |
1562 | /* If X is a NaN, use zero instead and show we have an overflow. |
1563 | Otherwise, range check. */ | |
1564 | if (REAL_VALUE_ISNAN (x)) | |
1565 | overflow = 1, x = dconst0; | |
e1ee5cdc RH |
1566 | else if (! (REAL_VALUES_LESS (l, x) |
1567 | && !no_upper_bound | |
1568 | && REAL_VALUES_LESS (x, u))) | |
649ff3b4 RK |
1569 | overflow = 1; |
1570 | ||
6d716ca8 RS |
1571 | #ifndef REAL_ARITHMETIC |
1572 | { | |
906c4e36 RK |
1573 | HOST_WIDE_INT low, high; |
1574 | HOST_WIDE_INT half_word | |
1575 | = (HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2); | |
6d716ca8 | 1576 | |
5f610074 RK |
1577 | if (x < 0) |
1578 | x = -x; | |
6d716ca8 | 1579 | |
5f610074 RK |
1580 | high = (HOST_WIDE_INT) (x / half_word / half_word); |
1581 | x -= (REAL_VALUE_TYPE) high * half_word * half_word; | |
1582 | if (x >= (REAL_VALUE_TYPE) half_word * half_word / 2) | |
b6b19f41 | 1583 | { |
5f610074 | 1584 | low = x - (REAL_VALUE_TYPE) half_word * half_word / 2; |
e0f776fb | 1585 | low |= (HOST_WIDE_INT) -1 << (HOST_BITS_PER_WIDE_INT - 1); |
b6b19f41 RS |
1586 | } |
1587 | else | |
5f610074 | 1588 | low = (HOST_WIDE_INT) x; |
6d716ca8 RS |
1589 | if (TREE_REAL_CST (arg1) < 0) |
1590 | neg_double (low, high, &low, &high); | |
1591 | t = build_int_2 (low, high); | |
1592 | } | |
1593 | #else | |
1594 | { | |
906c4e36 | 1595 | HOST_WIDE_INT low, high; |
5f610074 | 1596 | REAL_VALUE_TO_INT (&low, &high, x); |
6d716ca8 RS |
1597 | t = build_int_2 (low, high); |
1598 | } | |
1599 | #endif | |
1600 | TREE_TYPE (t) = type; | |
649ff3b4 RK |
1601 | TREE_OVERFLOW (t) |
1602 | = TREE_OVERFLOW (arg1) | force_fit_type (t, overflow); | |
1603 | TREE_CONSTANT_OVERFLOW (t) | |
1604 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
6d716ca8 RS |
1605 | } |
1606 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
1607 | TREE_TYPE (t) = type; | |
1608 | } | |
1609 | else if (TREE_CODE (type) == REAL_TYPE) | |
1610 | { | |
1611 | #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) | |
1612 | if (TREE_CODE (arg1) == INTEGER_CST) | |
1613 | return build_real_from_int_cst (type, arg1); | |
1614 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
1615 | if (TREE_CODE (arg1) == REAL_CST) | |
7c7b029d | 1616 | { |
5f610074 | 1617 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))) |
a377ff85 RK |
1618 | { |
1619 | t = arg1; | |
1620 | TREE_TYPE (arg1) = type; | |
1621 | return t; | |
1622 | } | |
5f610074 | 1623 | else if (setjmp (float_error)) |
7c7b029d | 1624 | { |
649ff3b4 RK |
1625 | overflow = 1; |
1626 | t = copy_node (arg1); | |
1627 | goto got_it; | |
7c7b029d RS |
1628 | } |
1629 | set_float_handler (float_error); | |
1630 | ||
5352b11a | 1631 | t = build_real (type, real_value_truncate (TYPE_MODE (type), |
7c7b029d | 1632 | TREE_REAL_CST (arg1))); |
906c4e36 | 1633 | set_float_handler (NULL_PTR); |
649ff3b4 RK |
1634 | |
1635 | got_it: | |
1636 | TREE_OVERFLOW (t) | |
1637 | = TREE_OVERFLOW (arg1) | force_fit_type (t, overflow); | |
1638 | TREE_CONSTANT_OVERFLOW (t) | |
1639 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1); | |
7c7b029d RS |
1640 | return t; |
1641 | } | |
6d716ca8 RS |
1642 | } |
1643 | TREE_CONSTANT (t) = 1; | |
1644 | return t; | |
1645 | } | |
1646 | \f | |
d023bff9 RS |
1647 | /* Return an expr equal to X but certainly not valid as an lvalue. |
1648 | Also make sure it is not valid as an null pointer constant. */ | |
6d716ca8 RS |
1649 | |
1650 | tree | |
1651 | non_lvalue (x) | |
1652 | tree x; | |
1653 | { | |
1654 | tree result; | |
1655 | ||
1656 | /* These things are certainly not lvalues. */ | |
1657 | if (TREE_CODE (x) == NON_LVALUE_EXPR | |
1658 | || TREE_CODE (x) == INTEGER_CST | |
1659 | || TREE_CODE (x) == REAL_CST | |
1660 | || TREE_CODE (x) == STRING_CST | |
1661 | || TREE_CODE (x) == ADDR_EXPR) | |
d023bff9 RS |
1662 | { |
1663 | if (TREE_CODE (x) == INTEGER_CST && integer_zerop (x)) | |
1664 | { | |
b1aa345d RS |
1665 | /* Use NOP_EXPR instead of NON_LVALUE_EXPR |
1666 | so convert_for_assignment won't strip it. | |
1667 | This is so this 0 won't be treated as a null pointer constant. */ | |
d023bff9 RS |
1668 | result = build1 (NOP_EXPR, TREE_TYPE (x), x); |
1669 | TREE_CONSTANT (result) = TREE_CONSTANT (x); | |
1670 | return result; | |
1671 | } | |
1672 | return x; | |
1673 | } | |
6d716ca8 RS |
1674 | |
1675 | result = build1 (NON_LVALUE_EXPR, TREE_TYPE (x), x); | |
1676 | TREE_CONSTANT (result) = TREE_CONSTANT (x); | |
1677 | return result; | |
1678 | } | |
a5e9b124 | 1679 | |
e9866da3 JM |
1680 | /* Nonzero means lvalues are limited to those valid in pedantic ANSI C. |
1681 | Zero means allow extended lvalues. */ | |
1682 | ||
1683 | int pedantic_lvalues; | |
1684 | ||
a5e9b124 JW |
1685 | /* When pedantic, return an expr equal to X but certainly not valid as a |
1686 | pedantic lvalue. Otherwise, return X. */ | |
1687 | ||
1688 | tree | |
1689 | pedantic_non_lvalue (x) | |
1690 | tree x; | |
1691 | { | |
e9866da3 | 1692 | if (pedantic_lvalues) |
a5e9b124 JW |
1693 | return non_lvalue (x); |
1694 | else | |
1695 | return x; | |
1696 | } | |
c05a9b68 RS |
1697 | \f |
1698 | /* Given a tree comparison code, return the code that is the logical inverse | |
1699 | of the given code. It is not safe to do this for floating-point | |
1700 | comparisons, except for NE_EXPR and EQ_EXPR. */ | |
6d716ca8 | 1701 | |
c05a9b68 RS |
1702 | static enum tree_code |
1703 | invert_tree_comparison (code) | |
1704 | enum tree_code code; | |
1705 | { | |
1706 | switch (code) | |
1707 | { | |
1708 | case EQ_EXPR: | |
1709 | return NE_EXPR; | |
1710 | case NE_EXPR: | |
1711 | return EQ_EXPR; | |
1712 | case GT_EXPR: | |
1713 | return LE_EXPR; | |
1714 | case GE_EXPR: | |
1715 | return LT_EXPR; | |
1716 | case LT_EXPR: | |
1717 | return GE_EXPR; | |
1718 | case LE_EXPR: | |
1719 | return GT_EXPR; | |
1720 | default: | |
1721 | abort (); | |
1722 | } | |
1723 | } | |
1724 | ||
1725 | /* Similar, but return the comparison that results if the operands are | |
1726 | swapped. This is safe for floating-point. */ | |
1727 | ||
1728 | static enum tree_code | |
1729 | swap_tree_comparison (code) | |
1730 | enum tree_code code; | |
1731 | { | |
1732 | switch (code) | |
1733 | { | |
1734 | case EQ_EXPR: | |
1735 | case NE_EXPR: | |
1736 | return code; | |
1737 | case GT_EXPR: | |
1738 | return LT_EXPR; | |
1739 | case GE_EXPR: | |
1740 | return LE_EXPR; | |
1741 | case LT_EXPR: | |
1742 | return GT_EXPR; | |
1743 | case LE_EXPR: | |
1744 | return GE_EXPR; | |
1745 | default: | |
1746 | abort (); | |
1747 | } | |
1748 | } | |
61f275ff RK |
1749 | |
1750 | /* Return nonzero if CODE is a tree code that represents a truth value. */ | |
1751 | ||
1752 | static int | |
1753 | truth_value_p (code) | |
1754 | enum tree_code code; | |
1755 | { | |
1756 | return (TREE_CODE_CLASS (code) == '<' | |
1757 | || code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR | |
1758 | || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR | |
1759 | || code == TRUTH_XOR_EXPR || code == TRUTH_NOT_EXPR); | |
1760 | } | |
c05a9b68 | 1761 | \f |
6a1746af RS |
1762 | /* Return nonzero if two operands are necessarily equal. |
1763 | If ONLY_CONST is non-zero, only return non-zero for constants. | |
1764 | This function tests whether the operands are indistinguishable; | |
1765 | it does not test whether they are equal using C's == operation. | |
1766 | The distinction is important for IEEE floating point, because | |
1767 | (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and | |
1768 | (2) two NaNs may be indistinguishable, but NaN!=NaN. */ | |
6d716ca8 RS |
1769 | |
1770 | int | |
1771 | operand_equal_p (arg0, arg1, only_const) | |
1772 | tree arg0, arg1; | |
1773 | int only_const; | |
1774 | { | |
1775 | /* If both types don't have the same signedness, then we can't consider | |
1776 | them equal. We must check this before the STRIP_NOPS calls | |
1777 | because they may change the signedness of the arguments. */ | |
1778 | if (TREE_UNSIGNED (TREE_TYPE (arg0)) != TREE_UNSIGNED (TREE_TYPE (arg1))) | |
1779 | return 0; | |
1780 | ||
1781 | STRIP_NOPS (arg0); | |
1782 | STRIP_NOPS (arg1); | |
1783 | ||
c7cfe938 RK |
1784 | if (TREE_CODE (arg0) != TREE_CODE (arg1) |
1785 | /* This is needed for conversions and for COMPONENT_REF. | |
1786 | Might as well play it safe and always test this. */ | |
1787 | || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1))) | |
6d716ca8 RS |
1788 | return 0; |
1789 | ||
c7cfe938 RK |
1790 | /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal. |
1791 | We don't care about side effects in that case because the SAVE_EXPR | |
1792 | takes care of that for us. In all other cases, two expressions are | |
1793 | equal if they have no side effects. If we have two identical | |
1794 | expressions with side effects that should be treated the same due | |
1795 | to the only side effects being identical SAVE_EXPR's, that will | |
1796 | be detected in the recursive calls below. */ | |
1797 | if (arg0 == arg1 && ! only_const | |
1798 | && (TREE_CODE (arg0) == SAVE_EXPR | |
1799 | || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1)))) | |
6d716ca8 RS |
1800 | return 1; |
1801 | ||
c7cfe938 RK |
1802 | /* Next handle constant cases, those for which we can return 1 even |
1803 | if ONLY_CONST is set. */ | |
1804 | if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1)) | |
1805 | switch (TREE_CODE (arg0)) | |
1806 | { | |
1807 | case INTEGER_CST: | |
3c9b0091 RK |
1808 | return (! TREE_CONSTANT_OVERFLOW (arg0) |
1809 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
1810 | && TREE_INT_CST_LOW (arg0) == TREE_INT_CST_LOW (arg1) | |
c7cfe938 RK |
1811 | && TREE_INT_CST_HIGH (arg0) == TREE_INT_CST_HIGH (arg1)); |
1812 | ||
1813 | case REAL_CST: | |
3c9b0091 RK |
1814 | return (! TREE_CONSTANT_OVERFLOW (arg0) |
1815 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
41c9120b PE |
1816 | && REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0), |
1817 | TREE_REAL_CST (arg1))); | |
c7cfe938 RK |
1818 | |
1819 | case COMPLEX_CST: | |
1820 | return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1), | |
1821 | only_const) | |
1822 | && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1), | |
1823 | only_const)); | |
1824 | ||
1825 | case STRING_CST: | |
1826 | return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1) | |
1827 | && ! strncmp (TREE_STRING_POINTER (arg0), | |
1828 | TREE_STRING_POINTER (arg1), | |
1829 | TREE_STRING_LENGTH (arg0))); | |
1830 | ||
1831 | case ADDR_EXPR: | |
1832 | return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), | |
1833 | 0); | |
e9a25f70 JL |
1834 | default: |
1835 | break; | |
c7cfe938 | 1836 | } |
6d716ca8 RS |
1837 | |
1838 | if (only_const) | |
1839 | return 0; | |
1840 | ||
6d716ca8 RS |
1841 | switch (TREE_CODE_CLASS (TREE_CODE (arg0))) |
1842 | { | |
1843 | case '1': | |
1844 | /* Two conversions are equal only if signedness and modes match. */ | |
1845 | if ((TREE_CODE (arg0) == NOP_EXPR || TREE_CODE (arg0) == CONVERT_EXPR) | |
1846 | && (TREE_UNSIGNED (TREE_TYPE (arg0)) | |
1847 | != TREE_UNSIGNED (TREE_TYPE (arg1)))) | |
1848 | return 0; | |
1849 | ||
1850 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
1851 | TREE_OPERAND (arg1, 0), 0); | |
1852 | ||
1853 | case '<': | |
1854 | case '2': | |
c7cfe938 RK |
1855 | if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0) |
1856 | && operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), | |
1857 | 0)) | |
1858 | return 1; | |
1859 | ||
1860 | /* For commutative ops, allow the other order. */ | |
1861 | return ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MULT_EXPR | |
1862 | || TREE_CODE (arg0) == MIN_EXPR || TREE_CODE (arg0) == MAX_EXPR | |
1863 | || TREE_CODE (arg0) == BIT_IOR_EXPR | |
1864 | || TREE_CODE (arg0) == BIT_XOR_EXPR | |
1865 | || TREE_CODE (arg0) == BIT_AND_EXPR | |
1866 | || TREE_CODE (arg0) == NE_EXPR || TREE_CODE (arg0) == EQ_EXPR) | |
1867 | && operand_equal_p (TREE_OPERAND (arg0, 0), | |
1868 | TREE_OPERAND (arg1, 1), 0) | |
6d716ca8 | 1869 | && operand_equal_p (TREE_OPERAND (arg0, 1), |
c7cfe938 | 1870 | TREE_OPERAND (arg1, 0), 0)); |
6d716ca8 RS |
1871 | |
1872 | case 'r': | |
1873 | switch (TREE_CODE (arg0)) | |
1874 | { | |
1875 | case INDIRECT_REF: | |
1876 | return operand_equal_p (TREE_OPERAND (arg0, 0), | |
1877 | TREE_OPERAND (arg1, 0), 0); | |
1878 | ||
1879 | case COMPONENT_REF: | |
1880 | case ARRAY_REF: | |
1881 | return (operand_equal_p (TREE_OPERAND (arg0, 0), | |
1882 | TREE_OPERAND (arg1, 0), 0) | |
1883 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
1884 | TREE_OPERAND (arg1, 1), 0)); | |
1885 | ||
1886 | case BIT_FIELD_REF: | |
1887 | return (operand_equal_p (TREE_OPERAND (arg0, 0), | |
1888 | TREE_OPERAND (arg1, 0), 0) | |
1889 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
1890 | TREE_OPERAND (arg1, 1), 0) | |
1891 | && operand_equal_p (TREE_OPERAND (arg0, 2), | |
1892 | TREE_OPERAND (arg1, 2), 0)); | |
e9a25f70 JL |
1893 | default: |
1894 | return 0; | |
6d716ca8 | 1895 | } |
e9a25f70 JL |
1896 | |
1897 | default: | |
1898 | return 0; | |
6d716ca8 | 1899 | } |
6d716ca8 | 1900 | } |
c05a9b68 RS |
1901 | \f |
1902 | /* Similar to operand_equal_p, but see if ARG0 might have been made by | |
1903 | shorten_compare from ARG1 when ARG1 was being compared with OTHER. | |
6d716ca8 | 1904 | |
6d716ca8 RS |
1905 | When in doubt, return 0. */ |
1906 | ||
1907 | static int | |
c05a9b68 RS |
1908 | operand_equal_for_comparison_p (arg0, arg1, other) |
1909 | tree arg0, arg1; | |
1910 | tree other; | |
6d716ca8 | 1911 | { |
c05a9b68 | 1912 | int unsignedp1, unsignedpo; |
52de9b6c | 1913 | tree primarg0, primarg1, primother; |
7a75868d | 1914 | unsigned correct_width; |
6d716ca8 | 1915 | |
c05a9b68 | 1916 | if (operand_equal_p (arg0, arg1, 0)) |
6d716ca8 RS |
1917 | return 1; |
1918 | ||
0982a4b8 JM |
1919 | if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0)) |
1920 | || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1))) | |
6d716ca8 RS |
1921 | return 0; |
1922 | ||
52de9b6c RK |
1923 | /* Discard any conversions that don't change the modes of ARG0 and ARG1 |
1924 | and see if the inner values are the same. This removes any | |
1925 | signedness comparison, which doesn't matter here. */ | |
1926 | primarg0 = arg0, primarg1 = arg1; | |
1927 | STRIP_NOPS (primarg0); STRIP_NOPS (primarg1); | |
1928 | if (operand_equal_p (primarg0, primarg1, 0)) | |
1929 | return 1; | |
1930 | ||
c05a9b68 RS |
1931 | /* Duplicate what shorten_compare does to ARG1 and see if that gives the |
1932 | actual comparison operand, ARG0. | |
6d716ca8 | 1933 | |
c05a9b68 | 1934 | First throw away any conversions to wider types |
6d716ca8 | 1935 | already present in the operands. */ |
6d716ca8 | 1936 | |
c05a9b68 RS |
1937 | primarg1 = get_narrower (arg1, &unsignedp1); |
1938 | primother = get_narrower (other, &unsignedpo); | |
1939 | ||
1940 | correct_width = TYPE_PRECISION (TREE_TYPE (arg1)); | |
1941 | if (unsignedp1 == unsignedpo | |
1942 | && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width | |
1943 | && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width) | |
6d716ca8 | 1944 | { |
c05a9b68 | 1945 | tree type = TREE_TYPE (arg0); |
6d716ca8 RS |
1946 | |
1947 | /* Make sure shorter operand is extended the right way | |
1948 | to match the longer operand. */ | |
c05a9b68 RS |
1949 | primarg1 = convert (signed_or_unsigned_type (unsignedp1, |
1950 | TREE_TYPE (primarg1)), | |
1951 | primarg1); | |
6d716ca8 | 1952 | |
c05a9b68 | 1953 | if (operand_equal_p (arg0, convert (type, primarg1), 0)) |
6d716ca8 RS |
1954 | return 1; |
1955 | } | |
1956 | ||
1957 | return 0; | |
1958 | } | |
1959 | \f | |
f72aed24 | 1960 | /* See if ARG is an expression that is either a comparison or is performing |
c05a9b68 RS |
1961 | arithmetic on comparisons. The comparisons must only be comparing |
1962 | two different values, which will be stored in *CVAL1 and *CVAL2; if | |
1963 | they are non-zero it means that some operands have already been found. | |
1964 | No variables may be used anywhere else in the expression except in the | |
35e66bd1 RK |
1965 | comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around |
1966 | the expression and save_expr needs to be called with CVAL1 and CVAL2. | |
c05a9b68 RS |
1967 | |
1968 | If this is true, return 1. Otherwise, return zero. */ | |
1969 | ||
1970 | static int | |
35e66bd1 | 1971 | twoval_comparison_p (arg, cval1, cval2, save_p) |
c05a9b68 RS |
1972 | tree arg; |
1973 | tree *cval1, *cval2; | |
35e66bd1 | 1974 | int *save_p; |
c05a9b68 RS |
1975 | { |
1976 | enum tree_code code = TREE_CODE (arg); | |
1977 | char class = TREE_CODE_CLASS (code); | |
1978 | ||
1979 | /* We can handle some of the 'e' cases here. */ | |
35e66bd1 | 1980 | if (class == 'e' && code == TRUTH_NOT_EXPR) |
c05a9b68 RS |
1981 | class = '1'; |
1982 | else if (class == 'e' | |
1983 | && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR | |
1984 | || code == COMPOUND_EXPR)) | |
1985 | class = '2'; | |
2315a5db RS |
1986 | |
1987 | /* ??? Disable this since the SAVE_EXPR might already be in use outside | |
1988 | the expression. There may be no way to make this work, but it needs | |
1989 | to be looked at again for 2.6. */ | |
1990 | #if 0 | |
35e66bd1 RK |
1991 | else if (class == 'e' && code == SAVE_EXPR && SAVE_EXPR_RTL (arg) == 0) |
1992 | { | |
1993 | /* If we've already found a CVAL1 or CVAL2, this expression is | |
1994 | two complex to handle. */ | |
1995 | if (*cval1 || *cval2) | |
1996 | return 0; | |
1997 | ||
1998 | class = '1'; | |
1999 | *save_p = 1; | |
2000 | } | |
2315a5db | 2001 | #endif |
c05a9b68 RS |
2002 | |
2003 | switch (class) | |
2004 | { | |
2005 | case '1': | |
35e66bd1 | 2006 | return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p); |
c05a9b68 RS |
2007 | |
2008 | case '2': | |
35e66bd1 RK |
2009 | return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p) |
2010 | && twoval_comparison_p (TREE_OPERAND (arg, 1), | |
2011 | cval1, cval2, save_p)); | |
c05a9b68 RS |
2012 | |
2013 | case 'c': | |
2014 | return 1; | |
2015 | ||
2016 | case 'e': | |
2017 | if (code == COND_EXPR) | |
35e66bd1 RK |
2018 | return (twoval_comparison_p (TREE_OPERAND (arg, 0), |
2019 | cval1, cval2, save_p) | |
2020 | && twoval_comparison_p (TREE_OPERAND (arg, 1), | |
2021 | cval1, cval2, save_p) | |
c05a9b68 | 2022 | && twoval_comparison_p (TREE_OPERAND (arg, 2), |
35e66bd1 | 2023 | cval1, cval2, save_p)); |
c05a9b68 RS |
2024 | return 0; |
2025 | ||
2026 | case '<': | |
2027 | /* First see if we can handle the first operand, then the second. For | |
2028 | the second operand, we know *CVAL1 can't be zero. It must be that | |
2029 | one side of the comparison is each of the values; test for the | |
2030 | case where this isn't true by failing if the two operands | |
2031 | are the same. */ | |
2032 | ||
2033 | if (operand_equal_p (TREE_OPERAND (arg, 0), | |
2034 | TREE_OPERAND (arg, 1), 0)) | |
2035 | return 0; | |
2036 | ||
2037 | if (*cval1 == 0) | |
2038 | *cval1 = TREE_OPERAND (arg, 0); | |
2039 | else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0)) | |
2040 | ; | |
2041 | else if (*cval2 == 0) | |
2042 | *cval2 = TREE_OPERAND (arg, 0); | |
2043 | else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0)) | |
2044 | ; | |
2045 | else | |
2046 | return 0; | |
2047 | ||
2048 | if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0)) | |
2049 | ; | |
2050 | else if (*cval2 == 0) | |
2051 | *cval2 = TREE_OPERAND (arg, 1); | |
2052 | else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0)) | |
2053 | ; | |
2054 | else | |
2055 | return 0; | |
2056 | ||
2057 | return 1; | |
c05a9b68 | 2058 | |
e9a25f70 JL |
2059 | default: |
2060 | return 0; | |
2061 | } | |
c05a9b68 RS |
2062 | } |
2063 | \f | |
2064 | /* ARG is a tree that is known to contain just arithmetic operations and | |
2065 | comparisons. Evaluate the operations in the tree substituting NEW0 for | |
f72aed24 | 2066 | any occurrence of OLD0 as an operand of a comparison and likewise for |
c05a9b68 RS |
2067 | NEW1 and OLD1. */ |
2068 | ||
2069 | static tree | |
2070 | eval_subst (arg, old0, new0, old1, new1) | |
2071 | tree arg; | |
2072 | tree old0, new0, old1, new1; | |
2073 | { | |
2074 | tree type = TREE_TYPE (arg); | |
2075 | enum tree_code code = TREE_CODE (arg); | |
2076 | char class = TREE_CODE_CLASS (code); | |
2077 | ||
2078 | /* We can handle some of the 'e' cases here. */ | |
2079 | if (class == 'e' && code == TRUTH_NOT_EXPR) | |
2080 | class = '1'; | |
2081 | else if (class == 'e' | |
2082 | && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)) | |
2083 | class = '2'; | |
2084 | ||
2085 | switch (class) | |
2086 | { | |
2087 | case '1': | |
2088 | return fold (build1 (code, type, | |
2089 | eval_subst (TREE_OPERAND (arg, 0), | |
2090 | old0, new0, old1, new1))); | |
2091 | ||
2092 | case '2': | |
2093 | return fold (build (code, type, | |
2094 | eval_subst (TREE_OPERAND (arg, 0), | |
2095 | old0, new0, old1, new1), | |
2096 | eval_subst (TREE_OPERAND (arg, 1), | |
2097 | old0, new0, old1, new1))); | |
2098 | ||
2099 | case 'e': | |
2100 | switch (code) | |
2101 | { | |
2102 | case SAVE_EXPR: | |
2103 | return eval_subst (TREE_OPERAND (arg, 0), old0, new0, old1, new1); | |
2104 | ||
2105 | case COMPOUND_EXPR: | |
2106 | return eval_subst (TREE_OPERAND (arg, 1), old0, new0, old1, new1); | |
2107 | ||
2108 | case COND_EXPR: | |
2109 | return fold (build (code, type, | |
2110 | eval_subst (TREE_OPERAND (arg, 0), | |
2111 | old0, new0, old1, new1), | |
2112 | eval_subst (TREE_OPERAND (arg, 1), | |
2113 | old0, new0, old1, new1), | |
2114 | eval_subst (TREE_OPERAND (arg, 2), | |
2115 | old0, new0, old1, new1))); | |
e9a25f70 JL |
2116 | default: |
2117 | break; | |
c05a9b68 | 2118 | } |
e9a25f70 | 2119 | /* fall through (???) */ |
c05a9b68 RS |
2120 | |
2121 | case '<': | |
2122 | { | |
2123 | tree arg0 = TREE_OPERAND (arg, 0); | |
2124 | tree arg1 = TREE_OPERAND (arg, 1); | |
2125 | ||
2126 | /* We need to check both for exact equality and tree equality. The | |
2127 | former will be true if the operand has a side-effect. In that | |
2128 | case, we know the operand occurred exactly once. */ | |
2129 | ||
2130 | if (arg0 == old0 || operand_equal_p (arg0, old0, 0)) | |
2131 | arg0 = new0; | |
2132 | else if (arg0 == old1 || operand_equal_p (arg0, old1, 0)) | |
2133 | arg0 = new1; | |
2134 | ||
2135 | if (arg1 == old0 || operand_equal_p (arg1, old0, 0)) | |
2136 | arg1 = new0; | |
2137 | else if (arg1 == old1 || operand_equal_p (arg1, old1, 0)) | |
2138 | arg1 = new1; | |
2139 | ||
2140 | return fold (build (code, type, arg0, arg1)); | |
2141 | } | |
c05a9b68 | 2142 | |
e9a25f70 JL |
2143 | default: |
2144 | return arg; | |
2145 | } | |
c05a9b68 RS |
2146 | } |
2147 | \f | |
6d716ca8 RS |
2148 | /* Return a tree for the case when the result of an expression is RESULT |
2149 | converted to TYPE and OMITTED was previously an operand of the expression | |
2150 | but is now not needed (e.g., we folded OMITTED * 0). | |
2151 | ||
2152 | If OMITTED has side effects, we must evaluate it. Otherwise, just do | |
2153 | the conversion of RESULT to TYPE. */ | |
2154 | ||
2155 | static tree | |
2156 | omit_one_operand (type, result, omitted) | |
2157 | tree type, result, omitted; | |
2158 | { | |
2159 | tree t = convert (type, result); | |
2160 | ||
2161 | if (TREE_SIDE_EFFECTS (omitted)) | |
2162 | return build (COMPOUND_EXPR, type, omitted, t); | |
2163 | ||
d023bff9 | 2164 | return non_lvalue (t); |
6d716ca8 | 2165 | } |
4ab3cb65 RK |
2166 | |
2167 | /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */ | |
2168 | ||
2169 | static tree | |
2170 | pedantic_omit_one_operand (type, result, omitted) | |
2171 | tree type, result, omitted; | |
2172 | { | |
2173 | tree t = convert (type, result); | |
2174 | ||
2175 | if (TREE_SIDE_EFFECTS (omitted)) | |
2176 | return build (COMPOUND_EXPR, type, omitted, t); | |
2177 | ||
2178 | return pedantic_non_lvalue (t); | |
2179 | } | |
2180 | ||
2181 | ||
6d716ca8 | 2182 | \f |
3f783329 RS |
2183 | /* Return a simplified tree node for the truth-negation of ARG. This |
2184 | never alters ARG itself. We assume that ARG is an operation that | |
6d716ca8 RS |
2185 | returns a truth value (0 or 1). */ |
2186 | ||
2187 | tree | |
2188 | invert_truthvalue (arg) | |
2189 | tree arg; | |
2190 | { | |
2191 | tree type = TREE_TYPE (arg); | |
c05a9b68 | 2192 | enum tree_code code = TREE_CODE (arg); |
6d716ca8 | 2193 | |
8ac1abdf JW |
2194 | if (code == ERROR_MARK) |
2195 | return arg; | |
2196 | ||
c05a9b68 RS |
2197 | /* If this is a comparison, we can simply invert it, except for |
2198 | floating-point non-equality comparisons, in which case we just | |
2199 | enclose a TRUTH_NOT_EXPR around what we have. */ | |
6d716ca8 | 2200 | |
c05a9b68 | 2201 | if (TREE_CODE_CLASS (code) == '<') |
6d716ca8 | 2202 | { |
7178e3af | 2203 | if (FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg, 0))) |
c05a9b68 RS |
2204 | && code != NE_EXPR && code != EQ_EXPR) |
2205 | return build1 (TRUTH_NOT_EXPR, type, arg); | |
2206 | else | |
ca46db87 | 2207 | return build (invert_tree_comparison (code), type, |
3f783329 | 2208 | TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1)); |
c05a9b68 | 2209 | } |
6d716ca8 | 2210 | |
c05a9b68 RS |
2211 | switch (code) |
2212 | { | |
6d716ca8 RS |
2213 | case INTEGER_CST: |
2214 | return convert (type, build_int_2 (TREE_INT_CST_LOW (arg) == 0 | |
2215 | && TREE_INT_CST_HIGH (arg) == 0, 0)); | |
2216 | ||
2217 | case TRUTH_AND_EXPR: | |
2218 | return build (TRUTH_OR_EXPR, type, | |
2219 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2220 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2221 | ||
2222 | case TRUTH_OR_EXPR: | |
2223 | return build (TRUTH_AND_EXPR, type, | |
2224 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2225 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2226 | ||
772447c5 RK |
2227 | case TRUTH_XOR_EXPR: |
2228 | /* Here we can invert either operand. We invert the first operand | |
2229 | unless the second operand is a TRUTH_NOT_EXPR in which case our | |
2230 | result is the XOR of the first operand with the inside of the | |
2231 | negation of the second operand. */ | |
2232 | ||
2233 | if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR) | |
2234 | return build (TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0), | |
2235 | TREE_OPERAND (TREE_OPERAND (arg, 1), 0)); | |
2236 | else | |
2237 | return build (TRUTH_XOR_EXPR, type, | |
2238 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2239 | TREE_OPERAND (arg, 1)); | |
2240 | ||
6d716ca8 RS |
2241 | case TRUTH_ANDIF_EXPR: |
2242 | return build (TRUTH_ORIF_EXPR, type, | |
2243 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2244 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2245 | ||
2246 | case TRUTH_ORIF_EXPR: | |
2247 | return build (TRUTH_ANDIF_EXPR, type, | |
2248 | invert_truthvalue (TREE_OPERAND (arg, 0)), | |
2249 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2250 | ||
2251 | case TRUTH_NOT_EXPR: | |
2252 | return TREE_OPERAND (arg, 0); | |
2253 | ||
2254 | case COND_EXPR: | |
2255 | return build (COND_EXPR, type, TREE_OPERAND (arg, 0), | |
2256 | invert_truthvalue (TREE_OPERAND (arg, 1)), | |
2257 | invert_truthvalue (TREE_OPERAND (arg, 2))); | |
2258 | ||
ef9fe0da RK |
2259 | case COMPOUND_EXPR: |
2260 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg, 0), | |
2261 | invert_truthvalue (TREE_OPERAND (arg, 1))); | |
2262 | ||
6d716ca8 RS |
2263 | case NON_LVALUE_EXPR: |
2264 | return invert_truthvalue (TREE_OPERAND (arg, 0)); | |
2265 | ||
2266 | case NOP_EXPR: | |
2267 | case CONVERT_EXPR: | |
2268 | case FLOAT_EXPR: | |
2269 | return build1 (TREE_CODE (arg), type, | |
2270 | invert_truthvalue (TREE_OPERAND (arg, 0))); | |
2271 | ||
2272 | case BIT_AND_EXPR: | |
efc1a4d9 PB |
2273 | if (!integer_onep (TREE_OPERAND (arg, 1))) |
2274 | break; | |
6d716ca8 | 2275 | return build (EQ_EXPR, type, arg, convert (type, integer_zero_node)); |
6d716ca8 | 2276 | |
dfa90b42 RS |
2277 | case SAVE_EXPR: |
2278 | return build1 (TRUTH_NOT_EXPR, type, arg); | |
a25ee332 RK |
2279 | |
2280 | case CLEANUP_POINT_EXPR: | |
2281 | return build1 (CLEANUP_POINT_EXPR, type, | |
2282 | invert_truthvalue (TREE_OPERAND (arg, 0))); | |
e9a25f70 JL |
2283 | |
2284 | default: | |
2285 | break; | |
efc1a4d9 PB |
2286 | } |
2287 | if (TREE_CODE (TREE_TYPE (arg)) != BOOLEAN_TYPE) | |
dfa90b42 | 2288 | abort (); |
efc1a4d9 | 2289 | return build1 (TRUTH_NOT_EXPR, type, arg); |
6d716ca8 RS |
2290 | } |
2291 | ||
2292 | /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both | |
2293 | operands are another bit-wise operation with a common input. If so, | |
2294 | distribute the bit operations to save an operation and possibly two if | |
2295 | constants are involved. For example, convert | |
2296 | (A | B) & (A | C) into A | (B & C) | |
2297 | Further simplification will occur if B and C are constants. | |
2298 | ||
2299 | If this optimization cannot be done, 0 will be returned. */ | |
2300 | ||
2301 | static tree | |
2302 | distribute_bit_expr (code, type, arg0, arg1) | |
2303 | enum tree_code code; | |
2304 | tree type; | |
2305 | tree arg0, arg1; | |
2306 | { | |
2307 | tree common; | |
2308 | tree left, right; | |
2309 | ||
2310 | if (TREE_CODE (arg0) != TREE_CODE (arg1) | |
2311 | || TREE_CODE (arg0) == code | |
fced8ba3 RS |
2312 | || (TREE_CODE (arg0) != BIT_AND_EXPR |
2313 | && TREE_CODE (arg0) != BIT_IOR_EXPR)) | |
6d716ca8 RS |
2314 | return 0; |
2315 | ||
2316 | if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0)) | |
2317 | { | |
2318 | common = TREE_OPERAND (arg0, 0); | |
2319 | left = TREE_OPERAND (arg0, 1); | |
2320 | right = TREE_OPERAND (arg1, 1); | |
2321 | } | |
2322 | else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0)) | |
2323 | { | |
2324 | common = TREE_OPERAND (arg0, 0); | |
2325 | left = TREE_OPERAND (arg0, 1); | |
2326 | right = TREE_OPERAND (arg1, 0); | |
2327 | } | |
2328 | else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0)) | |
2329 | { | |
2330 | common = TREE_OPERAND (arg0, 1); | |
2331 | left = TREE_OPERAND (arg0, 0); | |
2332 | right = TREE_OPERAND (arg1, 1); | |
2333 | } | |
2334 | else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0)) | |
2335 | { | |
2336 | common = TREE_OPERAND (arg0, 1); | |
2337 | left = TREE_OPERAND (arg0, 0); | |
2338 | right = TREE_OPERAND (arg1, 0); | |
2339 | } | |
2340 | else | |
2341 | return 0; | |
2342 | ||
2343 | return fold (build (TREE_CODE (arg0), type, common, | |
2344 | fold (build (code, type, left, right)))); | |
2345 | } | |
2346 | \f | |
2347 | /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER | |
2348 | starting at BITPOS. The field is unsigned if UNSIGNEDP is non-zero. */ | |
2349 | ||
2350 | static tree | |
2351 | make_bit_field_ref (inner, type, bitsize, bitpos, unsignedp) | |
2352 | tree inner; | |
2353 | tree type; | |
2354 | int bitsize, bitpos; | |
2355 | int unsignedp; | |
2356 | { | |
2357 | tree result = build (BIT_FIELD_REF, type, inner, | |
f8dac6eb | 2358 | size_int (bitsize), bitsize_int (bitpos, 0L)); |
6d716ca8 RS |
2359 | |
2360 | TREE_UNSIGNED (result) = unsignedp; | |
2361 | ||
2362 | return result; | |
2363 | } | |
2364 | ||
2365 | /* Optimize a bit-field compare. | |
2366 | ||
2367 | There are two cases: First is a compare against a constant and the | |
2368 | second is a comparison of two items where the fields are at the same | |
2369 | bit position relative to the start of a chunk (byte, halfword, word) | |
2370 | large enough to contain it. In these cases we can avoid the shift | |
2371 | implicit in bitfield extractions. | |
2372 | ||
2373 | For constants, we emit a compare of the shifted constant with the | |
2374 | BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being | |
2375 | compared. For two fields at the same position, we do the ANDs with the | |
2376 | similar mask and compare the result of the ANDs. | |
2377 | ||
2378 | CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR. | |
2379 | COMPARE_TYPE is the type of the comparison, and LHS and RHS | |
2380 | are the left and right operands of the comparison, respectively. | |
2381 | ||
6dc42e49 | 2382 | If the optimization described above can be done, we return the resulting |
6d716ca8 RS |
2383 | tree. Otherwise we return zero. */ |
2384 | ||
2385 | static tree | |
2386 | optimize_bit_field_compare (code, compare_type, lhs, rhs) | |
2387 | enum tree_code code; | |
2388 | tree compare_type; | |
2389 | tree lhs, rhs; | |
2390 | { | |
2391 | int lbitpos, lbitsize, rbitpos, rbitsize; | |
4e86caed | 2392 | int lnbitpos, lnbitsize, rnbitpos = 0, rnbitsize = 0; |
6d716ca8 RS |
2393 | tree type = TREE_TYPE (lhs); |
2394 | tree signed_type, unsigned_type; | |
2395 | int const_p = TREE_CODE (rhs) == INTEGER_CST; | |
4e86caed | 2396 | enum machine_mode lmode, rmode, lnmode, rnmode = VOIDmode; |
6d716ca8 RS |
2397 | int lunsignedp, runsignedp; |
2398 | int lvolatilep = 0, rvolatilep = 0; | |
23bd99ae | 2399 | int alignment; |
4e86caed | 2400 | tree linner, rinner = NULL_TREE; |
6d716ca8 | 2401 | tree mask; |
f1e60ec6 | 2402 | tree offset; |
6d716ca8 RS |
2403 | |
2404 | /* Get all the information about the extractions being done. If the bit size | |
2405 | if the same as the size of the underlying object, we aren't doing an | |
2406 | extraction at all and so can do nothing. */ | |
f1e60ec6 | 2407 | linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode, |
23bd99ae | 2408 | &lunsignedp, &lvolatilep, &alignment); |
9f5e873c | 2409 | if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0 |
f1e60ec6 | 2410 | || offset != 0) |
6d716ca8 RS |
2411 | return 0; |
2412 | ||
2413 | if (!const_p) | |
2414 | { | |
2415 | /* If this is not a constant, we can only do something if bit positions, | |
2416 | sizes, and signedness are the same. */ | |
23bd99ae RK |
2417 | rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode, |
2418 | &runsignedp, &rvolatilep, &alignment); | |
6d716ca8 | 2419 | |
9f5e873c | 2420 | if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize |
f1e60ec6 | 2421 | || lunsignedp != runsignedp || offset != 0) |
6d716ca8 RS |
2422 | return 0; |
2423 | } | |
2424 | ||
2425 | /* See if we can find a mode to refer to this field. We should be able to, | |
2426 | but fail if we can't. */ | |
2427 | lnmode = get_best_mode (lbitsize, lbitpos, | |
2428 | TYPE_ALIGN (TREE_TYPE (linner)), word_mode, | |
2429 | lvolatilep); | |
2430 | if (lnmode == VOIDmode) | |
2431 | return 0; | |
2432 | ||
2433 | /* Set signed and unsigned types of the precision of this mode for the | |
2434 | shifts below. */ | |
2435 | signed_type = type_for_mode (lnmode, 0); | |
2436 | unsigned_type = type_for_mode (lnmode, 1); | |
2437 | ||
2438 | if (! const_p) | |
2439 | { | |
2440 | rnmode = get_best_mode (rbitsize, rbitpos, | |
2441 | TYPE_ALIGN (TREE_TYPE (rinner)), word_mode, | |
2442 | rvolatilep); | |
2443 | if (rnmode == VOIDmode) | |
2444 | return 0; | |
2445 | } | |
2446 | ||
2447 | /* Compute the bit position and size for the new reference and our offset | |
2448 | within it. If the new reference is the same size as the original, we | |
2449 | won't optimize anything, so return zero. */ | |
2450 | lnbitsize = GET_MODE_BITSIZE (lnmode); | |
2451 | lnbitpos = lbitpos & ~ (lnbitsize - 1); | |
2452 | lbitpos -= lnbitpos; | |
2453 | if (lnbitsize == lbitsize) | |
2454 | return 0; | |
2455 | ||
2456 | if (! const_p) | |
2457 | { | |
2458 | rnbitsize = GET_MODE_BITSIZE (rnmode); | |
2459 | rnbitpos = rbitpos & ~ (rnbitsize - 1); | |
2460 | rbitpos -= rnbitpos; | |
2461 | if (rnbitsize == rbitsize) | |
2462 | return 0; | |
2463 | } | |
2464 | ||
f76b9db2 ILT |
2465 | if (BYTES_BIG_ENDIAN) |
2466 | lbitpos = lnbitsize - lbitsize - lbitpos; | |
6d716ca8 RS |
2467 | |
2468 | /* Make the mask to be used against the extracted field. */ | |
13af526d RS |
2469 | mask = build_int_2 (~0, ~0); |
2470 | TREE_TYPE (mask) = unsigned_type; | |
aa830baf | 2471 | force_fit_type (mask, 0); |
13af526d | 2472 | mask = convert (unsigned_type, mask); |
91d33e36 | 2473 | mask = const_binop (LSHIFT_EXPR, mask, size_int (lnbitsize - lbitsize), 0); |
6d716ca8 | 2474 | mask = const_binop (RSHIFT_EXPR, mask, |
91d33e36 | 2475 | size_int (lnbitsize - lbitsize - lbitpos), 0); |
6d716ca8 RS |
2476 | |
2477 | if (! const_p) | |
2478 | /* If not comparing with constant, just rework the comparison | |
2479 | and return. */ | |
2480 | return build (code, compare_type, | |
c0b9d4c8 RK |
2481 | build (BIT_AND_EXPR, unsigned_type, |
2482 | make_bit_field_ref (linner, unsigned_type, | |
2483 | lnbitsize, lnbitpos, 1), | |
6d716ca8 | 2484 | mask), |
c0b9d4c8 RK |
2485 | build (BIT_AND_EXPR, unsigned_type, |
2486 | make_bit_field_ref (rinner, unsigned_type, | |
2487 | rnbitsize, rnbitpos, 1), | |
6d716ca8 RS |
2488 | mask)); |
2489 | ||
2490 | /* Otherwise, we are handling the constant case. See if the constant is too | |
2491 | big for the field. Warn and return a tree of for 0 (false) if so. We do | |
2492 | this not only for its own sake, but to avoid having to test for this | |
2493 | error case below. If we didn't, we might generate wrong code. | |
2494 | ||
2495 | For unsigned fields, the constant shifted right by the field length should | |
2496 | be all zero. For signed fields, the high-order bits should agree with | |
2497 | the sign bit. */ | |
2498 | ||
2499 | if (lunsignedp) | |
2500 | { | |
2501 | if (! integer_zerop (const_binop (RSHIFT_EXPR, | |
2502 | convert (unsigned_type, rhs), | |
91d33e36 | 2503 | size_int (lbitsize), 0))) |
6d716ca8 RS |
2504 | { |
2505 | warning ("comparison is always %s due to width of bitfield", | |
2506 | code == NE_EXPR ? "one" : "zero"); | |
2507 | return convert (compare_type, | |
2508 | (code == NE_EXPR | |
2509 | ? integer_one_node : integer_zero_node)); | |
2510 | } | |
2511 | } | |
2512 | else | |
2513 | { | |
2514 | tree tem = const_binop (RSHIFT_EXPR, convert (signed_type, rhs), | |
91d33e36 | 2515 | size_int (lbitsize - 1), 0); |
6d716ca8 RS |
2516 | if (! integer_zerop (tem) && ! integer_all_onesp (tem)) |
2517 | { | |
2518 | warning ("comparison is always %s due to width of bitfield", | |
2519 | code == NE_EXPR ? "one" : "zero"); | |
2520 | return convert (compare_type, | |
2521 | (code == NE_EXPR | |
2522 | ? integer_one_node : integer_zero_node)); | |
2523 | } | |
2524 | } | |
2525 | ||
2526 | /* Single-bit compares should always be against zero. */ | |
2527 | if (lbitsize == 1 && ! integer_zerop (rhs)) | |
2528 | { | |
2529 | code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR; | |
2530 | rhs = convert (type, integer_zero_node); | |
2531 | } | |
2532 | ||
2533 | /* Make a new bitfield reference, shift the constant over the | |
2534 | appropriate number of bits and mask it with the computed mask | |
2535 | (in case this was a signed field). If we changed it, make a new one. */ | |
c0b9d4c8 | 2536 | lhs = make_bit_field_ref (linner, unsigned_type, lnbitsize, lnbitpos, 1); |
9db73acb RK |
2537 | if (lvolatilep) |
2538 | { | |
2539 | TREE_SIDE_EFFECTS (lhs) = 1; | |
2540 | TREE_THIS_VOLATILE (lhs) = 1; | |
2541 | } | |
6d716ca8 | 2542 | |
c0b9d4c8 RK |
2543 | rhs = fold (const_binop (BIT_AND_EXPR, |
2544 | const_binop (LSHIFT_EXPR, | |
2545 | convert (unsigned_type, rhs), | |
194c082f | 2546 | size_int (lbitpos), 0), |
91d33e36 | 2547 | mask, 0)); |
6d716ca8 RS |
2548 | |
2549 | return build (code, compare_type, | |
c0b9d4c8 | 2550 | build (BIT_AND_EXPR, unsigned_type, lhs, mask), |
6d716ca8 RS |
2551 | rhs); |
2552 | } | |
2553 | \f | |
b2215d83 | 2554 | /* Subroutine for fold_truthop: decode a field reference. |
6d716ca8 RS |
2555 | |
2556 | If EXP is a comparison reference, we return the innermost reference. | |
2557 | ||
2558 | *PBITSIZE is set to the number of bits in the reference, *PBITPOS is | |
2559 | set to the starting bit number. | |
2560 | ||
2561 | If the innermost field can be completely contained in a mode-sized | |
2562 | unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode. | |
2563 | ||
2564 | *PVOLATILEP is set to 1 if the any expression encountered is volatile; | |
2565 | otherwise it is not changed. | |
2566 | ||
2567 | *PUNSIGNEDP is set to the signedness of the field. | |
2568 | ||
2569 | *PMASK is set to the mask used. This is either contained in a | |
2570 | BIT_AND_EXPR or derived from the width of the field. | |
2571 | ||
38e01259 | 2572 | *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any. |
d4453ee5 | 2573 | |
6d716ca8 RS |
2574 | Return 0 if this is not a component reference or is one that we can't |
2575 | do anything with. */ | |
2576 | ||
2577 | static tree | |
2578 | decode_field_reference (exp, pbitsize, pbitpos, pmode, punsignedp, | |
d4453ee5 | 2579 | pvolatilep, pmask, pand_mask) |
6d716ca8 RS |
2580 | tree exp; |
2581 | int *pbitsize, *pbitpos; | |
2582 | enum machine_mode *pmode; | |
2583 | int *punsignedp, *pvolatilep; | |
2584 | tree *pmask; | |
d4453ee5 | 2585 | tree *pand_mask; |
6d716ca8 | 2586 | { |
6d9f1f5f RK |
2587 | tree and_mask = 0; |
2588 | tree mask, inner, offset; | |
2589 | tree unsigned_type; | |
2590 | int precision; | |
23bd99ae | 2591 | int alignment; |
6d716ca8 | 2592 | |
772ae9f0 RK |
2593 | /* All the optimizations using this function assume integer fields. |
2594 | There are problems with FP fields since the type_for_size call | |
2595 | below can fail for, e.g., XFmode. */ | |
2596 | if (! INTEGRAL_TYPE_P (TREE_TYPE (exp))) | |
2597 | return 0; | |
2598 | ||
6d716ca8 RS |
2599 | STRIP_NOPS (exp); |
2600 | ||
2601 | if (TREE_CODE (exp) == BIT_AND_EXPR) | |
2602 | { | |
6d9f1f5f | 2603 | and_mask = TREE_OPERAND (exp, 1); |
6d716ca8 | 2604 | exp = TREE_OPERAND (exp, 0); |
6d9f1f5f RK |
2605 | STRIP_NOPS (exp); STRIP_NOPS (and_mask); |
2606 | if (TREE_CODE (and_mask) != INTEGER_CST) | |
6d716ca8 RS |
2607 | return 0; |
2608 | } | |
2609 | ||
6d716ca8 | 2610 | |
f1e60ec6 | 2611 | inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode, |
23bd99ae | 2612 | punsignedp, pvolatilep, &alignment); |
02103577 RK |
2613 | if ((inner == exp && and_mask == 0) |
2614 | || *pbitsize < 0 || offset != 0) | |
c05a9b68 | 2615 | return 0; |
6d716ca8 | 2616 | |
6d9f1f5f RK |
2617 | /* Compute the mask to access the bitfield. */ |
2618 | unsigned_type = type_for_size (*pbitsize, 1); | |
2619 | precision = TYPE_PRECISION (unsigned_type); | |
2620 | ||
2621 | mask = build_int_2 (~0, ~0); | |
2622 | TREE_TYPE (mask) = unsigned_type; | |
2623 | force_fit_type (mask, 0); | |
2624 | mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0); | |
2625 | mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0); | |
2626 | ||
2627 | /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */ | |
2628 | if (and_mask != 0) | |
2629 | mask = fold (build (BIT_AND_EXPR, unsigned_type, | |
2630 | convert (unsigned_type, and_mask), mask)); | |
6d716ca8 RS |
2631 | |
2632 | *pmask = mask; | |
d4453ee5 | 2633 | *pand_mask = and_mask; |
6d716ca8 RS |
2634 | return inner; |
2635 | } | |
2636 | ||
6dc42e49 | 2637 | /* Return non-zero if MASK represents a mask of SIZE ones in the low-order |
6d716ca8 RS |
2638 | bit positions. */ |
2639 | ||
2640 | static int | |
2641 | all_ones_mask_p (mask, size) | |
2642 | tree mask; | |
2643 | int size; | |
2644 | { | |
2645 | tree type = TREE_TYPE (mask); | |
2646 | int precision = TYPE_PRECISION (type); | |
13af526d | 2647 | tree tmask; |
6d716ca8 | 2648 | |
13af526d RS |
2649 | tmask = build_int_2 (~0, ~0); |
2650 | TREE_TYPE (tmask) = signed_type (type); | |
aa830baf | 2651 | force_fit_type (tmask, 0); |
6d716ca8 | 2652 | return |
02103577 RK |
2653 | tree_int_cst_equal (mask, |
2654 | const_binop (RSHIFT_EXPR, | |
2655 | const_binop (LSHIFT_EXPR, tmask, | |
2656 | size_int (precision - size), | |
2657 | 0), | |
2658 | size_int (precision - size), 0)); | |
6d716ca8 | 2659 | } |
b2215d83 TW |
2660 | |
2661 | /* Subroutine for fold_truthop: determine if an operand is simple enough | |
2662 | to be evaluated unconditionally. */ | |
2663 | ||
b2215d83 TW |
2664 | static int |
2665 | simple_operand_p (exp) | |
2666 | tree exp; | |
2667 | { | |
2668 | /* Strip any conversions that don't change the machine mode. */ | |
2669 | while ((TREE_CODE (exp) == NOP_EXPR | |
2670 | || TREE_CODE (exp) == CONVERT_EXPR) | |
2671 | && (TYPE_MODE (TREE_TYPE (exp)) | |
2672 | == TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))))) | |
2673 | exp = TREE_OPERAND (exp, 0); | |
2674 | ||
2675 | return (TREE_CODE_CLASS (TREE_CODE (exp)) == 'c' | |
2676 | || (TREE_CODE_CLASS (TREE_CODE (exp)) == 'd' | |
2677 | && ! TREE_ADDRESSABLE (exp) | |
2678 | && ! TREE_THIS_VOLATILE (exp) | |
8227896c TW |
2679 | && ! DECL_NONLOCAL (exp) |
2680 | /* Don't regard global variables as simple. They may be | |
2681 | allocated in ways unknown to the compiler (shared memory, | |
2682 | #pragma weak, etc). */ | |
2683 | && ! TREE_PUBLIC (exp) | |
2684 | && ! DECL_EXTERNAL (exp) | |
2685 | /* Loading a static variable is unduly expensive, but global | |
2686 | registers aren't expensive. */ | |
2687 | && (! TREE_STATIC (exp) || DECL_REGISTER (exp)))); | |
b2215d83 | 2688 | } |
6d716ca8 | 2689 | \f |
ebde8a27 RK |
2690 | /* The following functions are subroutines to fold_range_test and allow it to |
2691 | try to change a logical combination of comparisons into a range test. | |
2692 | ||
2693 | For example, both | |
2694 | X == 2 && X == 3 && X == 4 && X == 5 | |
2695 | and | |
2696 | X >= 2 && X <= 5 | |
2697 | are converted to | |
2698 | (unsigned) (X - 2) <= 3 | |
2699 | ||
956d6950 | 2700 | We describe each set of comparisons as being either inside or outside |
ebde8a27 RK |
2701 | a range, using a variable named like IN_P, and then describe the |
2702 | range with a lower and upper bound. If one of the bounds is omitted, | |
2703 | it represents either the highest or lowest value of the type. | |
2704 | ||
2705 | In the comments below, we represent a range by two numbers in brackets | |
956d6950 | 2706 | preceded by a "+" to designate being inside that range, or a "-" to |
ebde8a27 RK |
2707 | designate being outside that range, so the condition can be inverted by |
2708 | flipping the prefix. An omitted bound is represented by a "-". For | |
2709 | example, "- [-, 10]" means being outside the range starting at the lowest | |
2710 | possible value and ending at 10, in other words, being greater than 10. | |
2711 | The range "+ [-, -]" is always true and hence the range "- [-, -]" is | |
2712 | always false. | |
2713 | ||
2714 | We set up things so that the missing bounds are handled in a consistent | |
2715 | manner so neither a missing bound nor "true" and "false" need to be | |
2716 | handled using a special case. */ | |
2717 | ||
2718 | /* Return the result of applying CODE to ARG0 and ARG1, but handle the case | |
2719 | of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P | |
2720 | and UPPER1_P are nonzero if the respective argument is an upper bound | |
2721 | and zero for a lower. TYPE, if nonzero, is the type of the result; it | |
2722 | must be specified for a comparison. ARG1 will be converted to ARG0's | |
2723 | type if both are specified. */ | |
ef659ec0 | 2724 | |
ebde8a27 RK |
2725 | static tree |
2726 | range_binop (code, type, arg0, upper0_p, arg1, upper1_p) | |
2727 | enum tree_code code; | |
2728 | tree type; | |
2729 | tree arg0, arg1; | |
2730 | int upper0_p, upper1_p; | |
2731 | { | |
27bae8e5 | 2732 | tree tem; |
ebde8a27 RK |
2733 | int result; |
2734 | int sgn0, sgn1; | |
ef659ec0 | 2735 | |
ebde8a27 RK |
2736 | /* If neither arg represents infinity, do the normal operation. |
2737 | Else, if not a comparison, return infinity. Else handle the special | |
2738 | comparison rules. Note that most of the cases below won't occur, but | |
2739 | are handled for consistency. */ | |
ef659ec0 | 2740 | |
ebde8a27 | 2741 | if (arg0 != 0 && arg1 != 0) |
27bae8e5 RK |
2742 | { |
2743 | tem = fold (build (code, type != 0 ? type : TREE_TYPE (arg0), | |
2744 | arg0, convert (TREE_TYPE (arg0), arg1))); | |
2745 | STRIP_NOPS (tem); | |
2746 | return TREE_CODE (tem) == INTEGER_CST ? tem : 0; | |
2747 | } | |
ef659ec0 | 2748 | |
ebde8a27 RK |
2749 | if (TREE_CODE_CLASS (code) != '<') |
2750 | return 0; | |
2751 | ||
2752 | /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0 | |
2753 | for neither. Then compute our result treating them as never equal | |
2754 | and comparing bounds to non-bounds as above. */ | |
2755 | sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1); | |
4e644c93 | 2756 | sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1); |
ebde8a27 RK |
2757 | switch (code) |
2758 | { | |
2759 | case EQ_EXPR: case NE_EXPR: | |
2760 | result = (code == NE_EXPR); | |
2761 | break; | |
2762 | case LT_EXPR: case LE_EXPR: | |
2763 | result = sgn0 < sgn1; | |
2764 | break; | |
2765 | case GT_EXPR: case GE_EXPR: | |
2766 | result = sgn0 > sgn1; | |
2767 | break; | |
e9a25f70 JL |
2768 | default: |
2769 | abort (); | |
ebde8a27 RK |
2770 | } |
2771 | ||
2772 | return convert (type, result ? integer_one_node : integer_zero_node); | |
2773 | } | |
2774 | \f | |
2775 | /* Given EXP, a logical expression, set the range it is testing into | |
2776 | variables denoted by PIN_P, PLOW, and PHIGH. Return the expression | |
2777 | actually being tested. *PLOW and *PHIGH will have be made the same type | |
2778 | as the returned expression. If EXP is not a comparison, we will most | |
2779 | likely not be returning a useful value and range. */ | |
ef659ec0 | 2780 | |
6dc7571d | 2781 | static tree |
ebde8a27 RK |
2782 | make_range (exp, pin_p, plow, phigh) |
2783 | tree exp; | |
2784 | int *pin_p; | |
2785 | tree *plow, *phigh; | |
ef659ec0 | 2786 | { |
ebde8a27 | 2787 | enum tree_code code; |
4e86caed | 2788 | tree arg0, arg1, type = NULL_TREE; |
ebde8a27 RK |
2789 | int in_p, n_in_p; |
2790 | tree low, high, n_low, n_high; | |
ef659ec0 | 2791 | |
ebde8a27 RK |
2792 | /* Start with simply saying "EXP != 0" and then look at the code of EXP |
2793 | and see if we can refine the range. Some of the cases below may not | |
2794 | happen, but it doesn't seem worth worrying about this. We "continue" | |
2795 | the outer loop when we've changed something; otherwise we "break" | |
2796 | the switch, which will "break" the while. */ | |
ef659ec0 | 2797 | |
ebde8a27 RK |
2798 | in_p = 0, low = high = convert (TREE_TYPE (exp), integer_zero_node); |
2799 | ||
2800 | while (1) | |
ef659ec0 | 2801 | { |
ebde8a27 RK |
2802 | code = TREE_CODE (exp); |
2803 | arg0 = TREE_OPERAND (exp, 0), arg1 = TREE_OPERAND (exp, 1); | |
80906567 RK |
2804 | if (TREE_CODE_CLASS (code) == '<' || TREE_CODE_CLASS (code) == '1' |
2805 | || TREE_CODE_CLASS (code) == '2') | |
ebde8a27 | 2806 | type = TREE_TYPE (arg0); |
ef659ec0 | 2807 | |
ebde8a27 RK |
2808 | switch (code) |
2809 | { | |
2810 | case TRUTH_NOT_EXPR: | |
2811 | in_p = ! in_p, exp = arg0; | |
2812 | continue; | |
2813 | ||
2814 | case EQ_EXPR: case NE_EXPR: | |
2815 | case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR: | |
2816 | /* We can only do something if the range is testing for zero | |
2817 | and if the second operand is an integer constant. Note that | |
2818 | saying something is "in" the range we make is done by | |
2819 | complementing IN_P since it will set in the initial case of | |
2820 | being not equal to zero; "out" is leaving it alone. */ | |
2821 | if (low == 0 || high == 0 | |
2822 | || ! integer_zerop (low) || ! integer_zerop (high) | |
2823 | || TREE_CODE (arg1) != INTEGER_CST) | |
2824 | break; | |
ef659ec0 | 2825 | |
ebde8a27 RK |
2826 | switch (code) |
2827 | { | |
2828 | case NE_EXPR: /* - [c, c] */ | |
2829 | low = high = arg1; | |
2830 | break; | |
2831 | case EQ_EXPR: /* + [c, c] */ | |
2832 | in_p = ! in_p, low = high = arg1; | |
2833 | break; | |
2834 | case GT_EXPR: /* - [-, c] */ | |
2835 | low = 0, high = arg1; | |
2836 | break; | |
2837 | case GE_EXPR: /* + [c, -] */ | |
2838 | in_p = ! in_p, low = arg1, high = 0; | |
2839 | break; | |
2840 | case LT_EXPR: /* - [c, -] */ | |
2841 | low = arg1, high = 0; | |
2842 | break; | |
2843 | case LE_EXPR: /* + [-, c] */ | |
2844 | in_p = ! in_p, low = 0, high = arg1; | |
2845 | break; | |
e9a25f70 JL |
2846 | default: |
2847 | abort (); | |
ebde8a27 | 2848 | } |
ef659ec0 | 2849 | |
ebde8a27 | 2850 | exp = arg0; |
ef659ec0 | 2851 | |
7f423031 | 2852 | /* If this is an unsigned comparison, we also know that EXP is |
0e1c7fc7 RK |
2853 | greater than or equal to zero. We base the range tests we make |
2854 | on that fact, so we record it here so we can parse existing | |
2855 | range tests. */ | |
7f423031 | 2856 | if (TREE_UNSIGNED (type) && (low == 0 || high == 0)) |
ebde8a27 RK |
2857 | { |
2858 | if (! merge_ranges (&n_in_p, &n_low, &n_high, in_p, low, high, | |
2859 | 1, convert (type, integer_zero_node), | |
0e1c7fc7 | 2860 | NULL_TREE)) |
ebde8a27 | 2861 | break; |
ef659ec0 | 2862 | |
ebde8a27 | 2863 | in_p = n_in_p, low = n_low, high = n_high; |
0e1c7fc7 RK |
2864 | |
2865 | /* If the high bound is missing, reverse the range so it | |
2866 | goes from zero to the low bound minus 1. */ | |
2867 | if (high == 0) | |
2868 | { | |
2869 | in_p = ! in_p; | |
2870 | high = range_binop (MINUS_EXPR, NULL_TREE, low, 0, | |
2871 | integer_one_node, 0); | |
2872 | low = convert (type, integer_zero_node); | |
2873 | } | |
ebde8a27 RK |
2874 | } |
2875 | continue; | |
2876 | ||
2877 | case NEGATE_EXPR: | |
2878 | /* (-x) IN [a,b] -> x in [-b, -a] */ | |
2879 | n_low = range_binop (MINUS_EXPR, type, | |
2880 | convert (type, integer_zero_node), 0, high, 1); | |
2881 | n_high = range_binop (MINUS_EXPR, type, | |
2882 | convert (type, integer_zero_node), 0, low, 0); | |
2883 | low = n_low, high = n_high; | |
2884 | exp = arg0; | |
2885 | continue; | |
2886 | ||
2887 | case BIT_NOT_EXPR: | |
2888 | /* ~ X -> -X - 1 */ | |
2889 | exp = build (MINUS_EXPR, type, build1 (NEGATE_EXPR, type, arg0), | |
27bae8e5 | 2890 | convert (type, integer_one_node)); |
ebde8a27 RK |
2891 | continue; |
2892 | ||
2893 | case PLUS_EXPR: case MINUS_EXPR: | |
2894 | if (TREE_CODE (arg1) != INTEGER_CST) | |
2895 | break; | |
2896 | ||
2897 | /* If EXP is signed, any overflow in the computation is undefined, | |
2898 | so we don't worry about it so long as our computations on | |
2899 | the bounds don't overflow. For unsigned, overflow is defined | |
2900 | and this is exactly the right thing. */ | |
2901 | n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR, | |
2902 | type, low, 0, arg1, 0); | |
2903 | n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR, | |
2904 | type, high, 1, arg1, 0); | |
2905 | if ((n_low != 0 && TREE_OVERFLOW (n_low)) | |
2906 | || (n_high != 0 && TREE_OVERFLOW (n_high))) | |
2907 | break; | |
2908 | ||
3c00684e JL |
2909 | /* Check for an unsigned range which has wrapped around the maximum |
2910 | value thus making n_high < n_low, and normalize it. */ | |
5a9d82a6 | 2911 | if (n_low && n_high && tree_int_cst_lt (n_high, n_low)) |
3c00684e JL |
2912 | { |
2913 | low = range_binop (PLUS_EXPR, type, n_high, 0, | |
0e1c7fc7 | 2914 | integer_one_node, 0); |
3c00684e | 2915 | high = range_binop (MINUS_EXPR, type, n_low, 0, |
0e1c7fc7 | 2916 | integer_one_node, 0); |
3c00684e JL |
2917 | in_p = ! in_p; |
2918 | } | |
5a9d82a6 JW |
2919 | else |
2920 | low = n_low, high = n_high; | |
27bae8e5 | 2921 | |
ebde8a27 RK |
2922 | exp = arg0; |
2923 | continue; | |
2924 | ||
2925 | case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR: | |
2926 | if (! INTEGRAL_TYPE_P (type) | |
2927 | || (low != 0 && ! int_fits_type_p (low, type)) | |
2928 | || (high != 0 && ! int_fits_type_p (high, type))) | |
2929 | break; | |
2930 | ||
ce2157a1 | 2931 | n_low = low, n_high = high; |
ebde8a27 | 2932 | |
ce2157a1 JL |
2933 | if (n_low != 0) |
2934 | n_low = convert (type, n_low); | |
2935 | ||
2936 | if (n_high != 0) | |
2937 | n_high = convert (type, n_high); | |
2938 | ||
2939 | /* If we're converting from an unsigned to a signed type, | |
2940 | we will be doing the comparison as unsigned. The tests above | |
2941 | have already verified that LOW and HIGH are both positive. | |
2942 | ||
2943 | So we have to make sure that the original unsigned value will | |
2944 | be interpreted as positive. */ | |
2945 | if (TREE_UNSIGNED (type) && ! TREE_UNSIGNED (TREE_TYPE (exp))) | |
2946 | { | |
2947 | tree equiv_type = type_for_mode (TYPE_MODE (type), 1); | |
e1ee5cdc RH |
2948 | tree high_positive; |
2949 | ||
2950 | /* A range without an upper bound is, naturally, unbounded. | |
2951 | Since convert would have cropped a very large value, use | |
2952 | the max value for the destination type. */ | |
2953 | ||
2954 | high_positive = TYPE_MAX_VALUE (equiv_type); | |
2955 | if (!high_positive) | |
2956 | { | |
2957 | high_positive = TYPE_MAX_VALUE (type); | |
2958 | if (!high_positive) | |
2959 | abort(); | |
2960 | } | |
2961 | high_positive = fold (build (RSHIFT_EXPR, type, | |
2962 | convert (type, high_positive), | |
2963 | convert (type, integer_one_node))); | |
ce2157a1 JL |
2964 | |
2965 | /* If the low bound is specified, "and" the range with the | |
2966 | range for which the original unsigned value will be | |
2967 | positive. */ | |
2968 | if (low != 0) | |
2969 | { | |
2970 | if (! merge_ranges (&n_in_p, &n_low, &n_high, | |
2971 | 1, n_low, n_high, | |
2972 | 1, convert (type, integer_zero_node), | |
2973 | high_positive)) | |
2974 | break; | |
2975 | ||
2976 | in_p = (n_in_p == in_p); | |
2977 | } | |
2978 | else | |
2979 | { | |
2980 | /* Otherwise, "or" the range with the range of the input | |
2981 | that will be interpreted as negative. */ | |
2982 | if (! merge_ranges (&n_in_p, &n_low, &n_high, | |
2983 | 0, n_low, n_high, | |
2984 | 1, convert (type, integer_zero_node), | |
2985 | high_positive)) | |
2986 | break; | |
2987 | ||
2988 | in_p = (in_p != n_in_p); | |
2989 | } | |
2990 | } | |
ebde8a27 RK |
2991 | |
2992 | exp = arg0; | |
ce2157a1 | 2993 | low = n_low, high = n_high; |
ebde8a27 | 2994 | continue; |
ce2157a1 JL |
2995 | |
2996 | default: | |
2997 | break; | |
ef659ec0 | 2998 | } |
ebde8a27 RK |
2999 | |
3000 | break; | |
ef659ec0 | 3001 | } |
ebde8a27 | 3002 | |
80906567 RK |
3003 | /* If EXP is a constant, we can evaluate whether this is true or false. */ |
3004 | if (TREE_CODE (exp) == INTEGER_CST) | |
3005 | { | |
3006 | in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node, | |
3007 | exp, 0, low, 0)) | |
3008 | && integer_onep (range_binop (LE_EXPR, integer_type_node, | |
3009 | exp, 1, high, 1))); | |
3010 | low = high = 0; | |
3011 | exp = 0; | |
3012 | } | |
3013 | ||
ebde8a27 RK |
3014 | *pin_p = in_p, *plow = low, *phigh = high; |
3015 | return exp; | |
3016 | } | |
3017 | \f | |
3018 | /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result | |
3019 | type, TYPE, return an expression to test if EXP is in (or out of, depending | |
3020 | on IN_P) the range. */ | |
3021 | ||
3022 | static tree | |
3023 | build_range_check (type, exp, in_p, low, high) | |
3024 | tree type; | |
3025 | tree exp; | |
3026 | int in_p; | |
3027 | tree low, high; | |
3028 | { | |
3029 | tree etype = TREE_TYPE (exp); | |
3030 | tree utype, value; | |
3031 | ||
3032 | if (! in_p | |
3033 | && (0 != (value = build_range_check (type, exp, 1, low, high)))) | |
3034 | return invert_truthvalue (value); | |
3035 | ||
3036 | else if (low == 0 && high == 0) | |
3037 | return convert (type, integer_one_node); | |
3038 | ||
3039 | else if (low == 0) | |
3040 | return fold (build (LE_EXPR, type, exp, high)); | |
3041 | ||
3042 | else if (high == 0) | |
3043 | return fold (build (GE_EXPR, type, exp, low)); | |
3044 | ||
3045 | else if (operand_equal_p (low, high, 0)) | |
3046 | return fold (build (EQ_EXPR, type, exp, low)); | |
3047 | ||
3048 | else if (TREE_UNSIGNED (etype) && integer_zerop (low)) | |
3049 | return build_range_check (type, exp, 1, 0, high); | |
3050 | ||
3051 | else if (integer_zerop (low)) | |
ef659ec0 | 3052 | { |
ebde8a27 RK |
3053 | utype = unsigned_type (etype); |
3054 | return build_range_check (type, convert (utype, exp), 1, 0, | |
3055 | convert (utype, high)); | |
3056 | } | |
ef659ec0 | 3057 | |
ebde8a27 RK |
3058 | else if (0 != (value = const_binop (MINUS_EXPR, high, low, 0)) |
3059 | && ! TREE_OVERFLOW (value)) | |
3060 | return build_range_check (type, | |
3061 | fold (build (MINUS_EXPR, etype, exp, low)), | |
3062 | 1, convert (etype, integer_zero_node), value); | |
3063 | else | |
3064 | return 0; | |
3065 | } | |
3066 | \f | |
3067 | /* Given two ranges, see if we can merge them into one. Return 1 if we | |
3068 | can, 0 if we can't. Set the output range into the specified parameters. */ | |
ef659ec0 | 3069 | |
ebde8a27 RK |
3070 | static int |
3071 | merge_ranges (pin_p, plow, phigh, in0_p, low0, high0, in1_p, low1, high1) | |
3072 | int *pin_p; | |
3073 | tree *plow, *phigh; | |
3074 | int in0_p, in1_p; | |
3075 | tree low0, high0, low1, high1; | |
3076 | { | |
3077 | int no_overlap; | |
3078 | int subset; | |
3079 | int temp; | |
3080 | tree tem; | |
3081 | int in_p; | |
3082 | tree low, high; | |
ce2157a1 JL |
3083 | int lowequal = ((low0 == 0 && low1 == 0) |
3084 | || integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3085 | low0, 0, low1, 0))); | |
3086 | int highequal = ((high0 == 0 && high1 == 0) | |
3087 | || integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3088 | high0, 1, high1, 1))); | |
3089 | ||
3090 | /* Make range 0 be the range that starts first, or ends last if they | |
3091 | start at the same value. Swap them if it isn't. */ | |
ebde8a27 RK |
3092 | if (integer_onep (range_binop (GT_EXPR, integer_type_node, |
3093 | low0, 0, low1, 0)) | |
ce2157a1 | 3094 | || (lowequal |
ebde8a27 | 3095 | && integer_onep (range_binop (GT_EXPR, integer_type_node, |
ce2157a1 | 3096 | high1, 1, high0, 1)))) |
ebde8a27 RK |
3097 | { |
3098 | temp = in0_p, in0_p = in1_p, in1_p = temp; | |
3099 | tem = low0, low0 = low1, low1 = tem; | |
3100 | tem = high0, high0 = high1, high1 = tem; | |
3101 | } | |
ef659ec0 | 3102 | |
ebde8a27 RK |
3103 | /* Now flag two cases, whether the ranges are disjoint or whether the |
3104 | second range is totally subsumed in the first. Note that the tests | |
3105 | below are simplified by the ones above. */ | |
3106 | no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node, | |
3107 | high0, 1, low1, 0)); | |
5df8a1f2 | 3108 | subset = integer_onep (range_binop (LE_EXPR, integer_type_node, |
ebde8a27 RK |
3109 | high1, 1, high0, 1)); |
3110 | ||
3111 | /* We now have four cases, depending on whether we are including or | |
3112 | excluding the two ranges. */ | |
3113 | if (in0_p && in1_p) | |
3114 | { | |
3115 | /* If they don't overlap, the result is false. If the second range | |
3116 | is a subset it is the result. Otherwise, the range is from the start | |
3117 | of the second to the end of the first. */ | |
3118 | if (no_overlap) | |
3119 | in_p = 0, low = high = 0; | |
3120 | else if (subset) | |
3121 | in_p = 1, low = low1, high = high1; | |
3122 | else | |
3123 | in_p = 1, low = low1, high = high0; | |
3124 | } | |
ef659ec0 | 3125 | |
ebde8a27 RK |
3126 | else if (in0_p && ! in1_p) |
3127 | { | |
ce2157a1 JL |
3128 | /* If they don't overlap, the result is the first range. If they are |
3129 | equal, the result is false. If the second range is a subset of the | |
3130 | first, and the ranges begin at the same place, we go from just after | |
3131 | the end of the first range to the end of the second. If the second | |
3132 | range is not a subset of the first, or if it is a subset and both | |
3133 | ranges end at the same place, the range starts at the start of the | |
3134 | first range and ends just before the second range. | |
3135 | Otherwise, we can't describe this as a single range. */ | |
ebde8a27 RK |
3136 | if (no_overlap) |
3137 | in_p = 1, low = low0, high = high0; | |
ce2157a1 | 3138 | else if (lowequal && highequal) |
405862dd | 3139 | in_p = 0, low = high = 0; |
ce2157a1 JL |
3140 | else if (subset && lowequal) |
3141 | { | |
3142 | in_p = 1, high = high0; | |
3143 | low = range_binop (PLUS_EXPR, NULL_TREE, high1, 0, | |
3144 | integer_one_node, 0); | |
3145 | } | |
3146 | else if (! subset || highequal) | |
ebde8a27 RK |
3147 | { |
3148 | in_p = 1, low = low0; | |
3149 | high = range_binop (MINUS_EXPR, NULL_TREE, low1, 0, | |
0e1c7fc7 | 3150 | integer_one_node, 0); |
ebde8a27 | 3151 | } |
ce2157a1 JL |
3152 | else |
3153 | return 0; | |
ebde8a27 | 3154 | } |
ef659ec0 | 3155 | |
ebde8a27 RK |
3156 | else if (! in0_p && in1_p) |
3157 | { | |
3158 | /* If they don't overlap, the result is the second range. If the second | |
3159 | is a subset of the first, the result is false. Otherwise, | |
3160 | the range starts just after the first range and ends at the | |
3161 | end of the second. */ | |
3162 | if (no_overlap) | |
3163 | in_p = 1, low = low1, high = high1; | |
3164 | else if (subset) | |
3165 | in_p = 0, low = high = 0; | |
3166 | else | |
3167 | { | |
3168 | in_p = 1, high = high1; | |
3169 | low = range_binop (PLUS_EXPR, NULL_TREE, high0, 1, | |
3170 | integer_one_node, 0); | |
ef659ec0 TW |
3171 | } |
3172 | } | |
3173 | ||
ebde8a27 RK |
3174 | else |
3175 | { | |
3176 | /* The case where we are excluding both ranges. Here the complex case | |
3177 | is if they don't overlap. In that case, the only time we have a | |
3178 | range is if they are adjacent. If the second is a subset of the | |
3179 | first, the result is the first. Otherwise, the range to exclude | |
3180 | starts at the beginning of the first range and ends at the end of the | |
3181 | second. */ | |
3182 | if (no_overlap) | |
3183 | { | |
3184 | if (integer_onep (range_binop (EQ_EXPR, integer_type_node, | |
3185 | range_binop (PLUS_EXPR, NULL_TREE, | |
3186 | high0, 1, | |
3187 | integer_one_node, 1), | |
3188 | 1, low1, 0))) | |
3189 | in_p = 0, low = low0, high = high1; | |
3190 | else | |
3191 | return 0; | |
3192 | } | |
3193 | else if (subset) | |
3194 | in_p = 0, low = low0, high = high0; | |
3195 | else | |
3196 | in_p = 0, low = low0, high = high1; | |
3197 | } | |
f5902869 | 3198 | |
ebde8a27 RK |
3199 | *pin_p = in_p, *plow = low, *phigh = high; |
3200 | return 1; | |
3201 | } | |
3202 | \f | |
3203 | /* EXP is some logical combination of boolean tests. See if we can | |
3204 | merge it into some range test. Return the new tree if so. */ | |
ef659ec0 | 3205 | |
ebde8a27 RK |
3206 | static tree |
3207 | fold_range_test (exp) | |
3208 | tree exp; | |
3209 | { | |
3210 | int or_op = (TREE_CODE (exp) == TRUTH_ORIF_EXPR | |
3211 | || TREE_CODE (exp) == TRUTH_OR_EXPR); | |
3212 | int in0_p, in1_p, in_p; | |
3213 | tree low0, low1, low, high0, high1, high; | |
3214 | tree lhs = make_range (TREE_OPERAND (exp, 0), &in0_p, &low0, &high0); | |
3215 | tree rhs = make_range (TREE_OPERAND (exp, 1), &in1_p, &low1, &high1); | |
3216 | tree tem; | |
ef659ec0 | 3217 | |
ebde8a27 RK |
3218 | /* If this is an OR operation, invert both sides; we will invert |
3219 | again at the end. */ | |
3220 | if (or_op) | |
3221 | in0_p = ! in0_p, in1_p = ! in1_p; | |
3222 | ||
3223 | /* If both expressions are the same, if we can merge the ranges, and we | |
80906567 RK |
3224 | can build the range test, return it or it inverted. If one of the |
3225 | ranges is always true or always false, consider it to be the same | |
3226 | expression as the other. */ | |
3227 | if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0)) | |
ebde8a27 RK |
3228 | && merge_ranges (&in_p, &low, &high, in0_p, low0, high0, |
3229 | in1_p, low1, high1) | |
80906567 RK |
3230 | && 0 != (tem = (build_range_check (TREE_TYPE (exp), |
3231 | lhs != 0 ? lhs | |
3232 | : rhs != 0 ? rhs : integer_zero_node, | |
ebde8a27 RK |
3233 | in_p, low, high)))) |
3234 | return or_op ? invert_truthvalue (tem) : tem; | |
3235 | ||
3236 | /* On machines where the branch cost is expensive, if this is a | |
3237 | short-circuited branch and the underlying object on both sides | |
3238 | is the same, make a non-short-circuit operation. */ | |
3239 | else if (BRANCH_COST >= 2 | |
3240 | && (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3241 | || TREE_CODE (exp) == TRUTH_ORIF_EXPR) | |
3242 | && operand_equal_p (lhs, rhs, 0)) | |
ef659ec0 | 3243 | { |
f0eebf28 RK |
3244 | /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR |
3245 | unless we are at top level, in which case we can't do this. */ | |
ebde8a27 RK |
3246 | if (simple_operand_p (lhs)) |
3247 | return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3248 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR, | |
3249 | TREE_TYPE (exp), TREE_OPERAND (exp, 0), | |
3250 | TREE_OPERAND (exp, 1)); | |
f0eebf28 RK |
3251 | |
3252 | else if (current_function_decl != 0) | |
ebde8a27 RK |
3253 | { |
3254 | tree common = save_expr (lhs); | |
3255 | ||
3256 | if (0 != (lhs = build_range_check (TREE_TYPE (exp), common, | |
3257 | or_op ? ! in0_p : in0_p, | |
3258 | low0, high0)) | |
3259 | && (0 != (rhs = build_range_check (TREE_TYPE (exp), common, | |
3260 | or_op ? ! in1_p : in1_p, | |
3261 | low1, high1)))) | |
3262 | return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR | |
3263 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR, | |
3264 | TREE_TYPE (exp), lhs, rhs); | |
3265 | } | |
ef659ec0 | 3266 | } |
de153e82 JL |
3267 | |
3268 | ||
3269 | return 0; | |
ef659ec0 TW |
3270 | } |
3271 | \f | |
02103577 | 3272 | /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P |
25216284 | 3273 | bit value. Arrange things so the extra bits will be set to zero if and |
d4453ee5 RK |
3274 | only if C is signed-extended to its full width. If MASK is nonzero, |
3275 | it is an INTEGER_CST that should be AND'ed with the extra bits. */ | |
02103577 RK |
3276 | |
3277 | static tree | |
d4453ee5 | 3278 | unextend (c, p, unsignedp, mask) |
02103577 RK |
3279 | tree c; |
3280 | int p; | |
3281 | int unsignedp; | |
d4453ee5 | 3282 | tree mask; |
02103577 RK |
3283 | { |
3284 | tree type = TREE_TYPE (c); | |
3285 | int modesize = GET_MODE_BITSIZE (TYPE_MODE (type)); | |
3286 | tree temp; | |
3287 | ||
3288 | if (p == modesize || unsignedp) | |
3289 | return c; | |
3290 | ||
02103577 | 3291 | /* We work by getting just the sign bit into the low-order bit, then |
9faa82d8 | 3292 | into the high-order bit, then sign-extend. We then XOR that value |
02103577 RK |
3293 | with C. */ |
3294 | temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1), 0); | |
3295 | temp = const_binop (BIT_AND_EXPR, temp, size_int (1), 0); | |
cf85c69b JW |
3296 | |
3297 | /* We must use a signed type in order to get an arithmetic right shift. | |
3298 | However, we must also avoid introducing accidental overflows, so that | |
3299 | a subsequent call to integer_zerop will work. Hence we must | |
3300 | do the type conversion here. At this point, the constant is either | |
3301 | zero or one, and the conversion to a signed type can never overflow. | |
3302 | We could get an overflow if this conversion is done anywhere else. */ | |
3303 | if (TREE_UNSIGNED (type)) | |
3304 | temp = convert (signed_type (type), temp); | |
3305 | ||
02103577 RK |
3306 | temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0); |
3307 | temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0); | |
d4453ee5 RK |
3308 | if (mask != 0) |
3309 | temp = const_binop (BIT_AND_EXPR, temp, convert (TREE_TYPE (c), mask), 0); | |
cf85c69b JW |
3310 | /* If necessary, convert the type back to match the type of C. */ |
3311 | if (TREE_UNSIGNED (type)) | |
3312 | temp = convert (type, temp); | |
d4453ee5 | 3313 | |
02103577 RK |
3314 | return convert (type, const_binop (BIT_XOR_EXPR, c, temp, 0)); |
3315 | } | |
3316 | \f | |
b2215d83 TW |
3317 | /* Find ways of folding logical expressions of LHS and RHS: |
3318 | Try to merge two comparisons to the same innermost item. | |
3319 | Look for range tests like "ch >= '0' && ch <= '9'". | |
3320 | Look for combinations of simple terms on machines with expensive branches | |
3321 | and evaluate the RHS unconditionally. | |
6d716ca8 RS |
3322 | |
3323 | For example, if we have p->a == 2 && p->b == 4 and we can make an | |
3324 | object large enough to span both A and B, we can do this with a comparison | |
3325 | against the object ANDed with the a mask. | |
3326 | ||
3327 | If we have p->a == q->a && p->b == q->b, we may be able to use bit masking | |
3328 | operations to do this with one comparison. | |
3329 | ||
3330 | We check for both normal comparisons and the BIT_AND_EXPRs made this by | |
3331 | function and the one above. | |
3332 | ||
3333 | CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR, | |
3334 | TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR. | |
3335 | ||
3336 | TRUTH_TYPE is the type of the logical operand and LHS and RHS are its | |
3337 | two operands. | |
3338 | ||
3339 | We return the simplified tree or 0 if no optimization is possible. */ | |
3340 | ||
3341 | static tree | |
b2215d83 | 3342 | fold_truthop (code, truth_type, lhs, rhs) |
6d716ca8 RS |
3343 | enum tree_code code; |
3344 | tree truth_type, lhs, rhs; | |
3345 | { | |
3346 | /* If this is the "or" of two comparisons, we can do something if we | |
3347 | the comparisons are NE_EXPR. If this is the "and", we can do something | |
3348 | if the comparisons are EQ_EXPR. I.e., | |
3349 | (a->b == 2 && a->c == 4) can become (a->new == NEW). | |
3350 | ||
3351 | WANTED_CODE is this operation code. For single bit fields, we can | |
3352 | convert EQ_EXPR to NE_EXPR so we need not reject the "wrong" | |
3353 | comparison for one-bit fields. */ | |
3354 | ||
b2215d83 | 3355 | enum tree_code wanted_code; |
6d716ca8 | 3356 | enum tree_code lcode, rcode; |
b2215d83 | 3357 | tree ll_arg, lr_arg, rl_arg, rr_arg; |
6d716ca8 RS |
3358 | tree ll_inner, lr_inner, rl_inner, rr_inner; |
3359 | int ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos; | |
3360 | int rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos; | |
3361 | int xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos; | |
3362 | int lnbitsize, lnbitpos, rnbitsize, rnbitpos; | |
3363 | int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp; | |
3364 | enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode; | |
3365 | enum machine_mode lnmode, rnmode; | |
3366 | tree ll_mask, lr_mask, rl_mask, rr_mask; | |
d4453ee5 | 3367 | tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask; |
b2215d83 | 3368 | tree l_const, r_const; |
6d716ca8 RS |
3369 | tree type, result; |
3370 | int first_bit, end_bit; | |
b2215d83 | 3371 | int volatilep; |
6d716ca8 | 3372 | |
ebde8a27 RK |
3373 | /* Start by getting the comparison codes. Fail if anything is volatile. |
3374 | If one operand is a BIT_AND_EXPR with the constant one, treat it as if | |
3375 | it were surrounded with a NE_EXPR. */ | |
6d716ca8 | 3376 | |
ebde8a27 | 3377 | if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs)) |
b2215d83 TW |
3378 | return 0; |
3379 | ||
6d716ca8 RS |
3380 | lcode = TREE_CODE (lhs); |
3381 | rcode = TREE_CODE (rhs); | |
ef659ec0 | 3382 | |
96d4cf0a RK |
3383 | if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1))) |
3384 | lcode = NE_EXPR, lhs = build (NE_EXPR, truth_type, lhs, integer_zero_node); | |
3385 | ||
3386 | if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1))) | |
3387 | rcode = NE_EXPR, rhs = build (NE_EXPR, truth_type, rhs, integer_zero_node); | |
3388 | ||
ebde8a27 | 3389 | if (TREE_CODE_CLASS (lcode) != '<' || TREE_CODE_CLASS (rcode) != '<') |
ef659ec0 TW |
3390 | return 0; |
3391 | ||
b2215d83 | 3392 | code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR) |
9c0ae98b | 3393 | ? TRUTH_AND_EXPR : TRUTH_OR_EXPR); |
b2215d83 TW |
3394 | |
3395 | ll_arg = TREE_OPERAND (lhs, 0); | |
3396 | lr_arg = TREE_OPERAND (lhs, 1); | |
3397 | rl_arg = TREE_OPERAND (rhs, 0); | |
3398 | rr_arg = TREE_OPERAND (rhs, 1); | |
3399 | ||
8227896c | 3400 | /* If the RHS can be evaluated unconditionally and its operands are |
b2215d83 TW |
3401 | simple, it wins to evaluate the RHS unconditionally on machines |
3402 | with expensive branches. In this case, this isn't a comparison | |
3403 | that can be merged. */ | |
3404 | ||
3405 | /* @@ I'm not sure it wins on the m88110 to do this if the comparisons | |
3406 | are with zero (tmw). */ | |
3407 | ||
3408 | if (BRANCH_COST >= 2 | |
7178e3af | 3409 | && INTEGRAL_TYPE_P (TREE_TYPE (rhs)) |
b2215d83 | 3410 | && simple_operand_p (rl_arg) |
8227896c | 3411 | && simple_operand_p (rr_arg)) |
b2215d83 TW |
3412 | return build (code, truth_type, lhs, rhs); |
3413 | ||
ef659ec0 TW |
3414 | /* See if the comparisons can be merged. Then get all the parameters for |
3415 | each side. */ | |
3416 | ||
6d716ca8 | 3417 | if ((lcode != EQ_EXPR && lcode != NE_EXPR) |
ef659ec0 | 3418 | || (rcode != EQ_EXPR && rcode != NE_EXPR)) |
6d716ca8 RS |
3419 | return 0; |
3420 | ||
b2215d83 TW |
3421 | volatilep = 0; |
3422 | ll_inner = decode_field_reference (ll_arg, | |
6d716ca8 | 3423 | &ll_bitsize, &ll_bitpos, &ll_mode, |
d4453ee5 RK |
3424 | &ll_unsignedp, &volatilep, &ll_mask, |
3425 | &ll_and_mask); | |
b2215d83 | 3426 | lr_inner = decode_field_reference (lr_arg, |
6d716ca8 | 3427 | &lr_bitsize, &lr_bitpos, &lr_mode, |
d4453ee5 RK |
3428 | &lr_unsignedp, &volatilep, &lr_mask, |
3429 | &lr_and_mask); | |
b2215d83 | 3430 | rl_inner = decode_field_reference (rl_arg, |
6d716ca8 | 3431 | &rl_bitsize, &rl_bitpos, &rl_mode, |
d4453ee5 RK |
3432 | &rl_unsignedp, &volatilep, &rl_mask, |
3433 | &rl_and_mask); | |
b2215d83 | 3434 | rr_inner = decode_field_reference (rr_arg, |
6d716ca8 | 3435 | &rr_bitsize, &rr_bitpos, &rr_mode, |
d4453ee5 RK |
3436 | &rr_unsignedp, &volatilep, &rr_mask, |
3437 | &rr_and_mask); | |
6d716ca8 RS |
3438 | |
3439 | /* It must be true that the inner operation on the lhs of each | |
3440 | comparison must be the same if we are to be able to do anything. | |
3441 | Then see if we have constants. If not, the same must be true for | |
3442 | the rhs's. */ | |
3443 | if (volatilep || ll_inner == 0 || rl_inner == 0 | |
3444 | || ! operand_equal_p (ll_inner, rl_inner, 0)) | |
3445 | return 0; | |
3446 | ||
b2215d83 TW |
3447 | if (TREE_CODE (lr_arg) == INTEGER_CST |
3448 | && TREE_CODE (rr_arg) == INTEGER_CST) | |
3449 | l_const = lr_arg, r_const = rr_arg; | |
6d716ca8 RS |
3450 | else if (lr_inner == 0 || rr_inner == 0 |
3451 | || ! operand_equal_p (lr_inner, rr_inner, 0)) | |
3452 | return 0; | |
b2215d83 TW |
3453 | else |
3454 | l_const = r_const = 0; | |
6d716ca8 RS |
3455 | |
3456 | /* If either comparison code is not correct for our logical operation, | |
3457 | fail. However, we can convert a one-bit comparison against zero into | |
3458 | the opposite comparison against that bit being set in the field. */ | |
b2215d83 | 3459 | |
9c0ae98b | 3460 | wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR); |
6d716ca8 RS |
3461 | if (lcode != wanted_code) |
3462 | { | |
3463 | if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask)) | |
5a6b3365 | 3464 | { |
9f29ca78 | 3465 | if (ll_unsignedp || tree_log2 (ll_mask) + 1 < ll_bitsize) |
5a6b3365 R |
3466 | l_const = ll_mask; |
3467 | else | |
3468 | /* Since ll_arg is a single bit bit mask, we can sign extend | |
3469 | it appropriately with a NEGATE_EXPR. | |
3470 | l_const is made a signed value here, but since for l_const != NULL | |
3471 | lr_unsignedp is not used, we don't need to clear the latter. */ | |
3472 | l_const = fold (build1 (NEGATE_EXPR, TREE_TYPE (ll_arg), | |
3473 | convert (TREE_TYPE (ll_arg), ll_mask))); | |
3474 | } | |
6d716ca8 RS |
3475 | else |
3476 | return 0; | |
3477 | } | |
3478 | ||
3479 | if (rcode != wanted_code) | |
3480 | { | |
3481 | if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask)) | |
5a6b3365 | 3482 | { |
9f29ca78 | 3483 | if (rl_unsignedp || tree_log2 (rl_mask) + 1 < rl_bitsize) |
5a6b3365 R |
3484 | r_const = rl_mask; |
3485 | else | |
3486 | /* This is analogous to the code for l_const above. */ | |
3487 | r_const = fold (build1 (NEGATE_EXPR, TREE_TYPE (rl_arg), | |
3488 | convert (TREE_TYPE (rl_arg), rl_mask))); | |
3489 | } | |
6d716ca8 RS |
3490 | else |
3491 | return 0; | |
3492 | } | |
3493 | ||
3494 | /* See if we can find a mode that contains both fields being compared on | |
3495 | the left. If we can't, fail. Otherwise, update all constants and masks | |
3496 | to be relative to a field of that size. */ | |
3497 | first_bit = MIN (ll_bitpos, rl_bitpos); | |
3498 | end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize); | |
3499 | lnmode = get_best_mode (end_bit - first_bit, first_bit, | |
3500 | TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode, | |
3501 | volatilep); | |
3502 | if (lnmode == VOIDmode) | |
3503 | return 0; | |
3504 | ||
3505 | lnbitsize = GET_MODE_BITSIZE (lnmode); | |
3506 | lnbitpos = first_bit & ~ (lnbitsize - 1); | |
3507 | type = type_for_size (lnbitsize, 1); | |
3508 | xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos; | |
3509 | ||
f76b9db2 ILT |
3510 | if (BYTES_BIG_ENDIAN) |
3511 | { | |
3512 | xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize; | |
3513 | xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize; | |
3514 | } | |
6d716ca8 RS |
3515 | |
3516 | ll_mask = const_binop (LSHIFT_EXPR, convert (type, ll_mask), | |
91d33e36 | 3517 | size_int (xll_bitpos), 0); |
6d716ca8 | 3518 | rl_mask = const_binop (LSHIFT_EXPR, convert (type, rl_mask), |
91d33e36 | 3519 | size_int (xrl_bitpos), 0); |
6d716ca8 | 3520 | |
6d716ca8 RS |
3521 | if (l_const) |
3522 | { | |
d4453ee5 RK |
3523 | l_const = convert (type, l_const); |
3524 | l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask); | |
02103577 RK |
3525 | l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos), 0); |
3526 | if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const, | |
3527 | fold (build1 (BIT_NOT_EXPR, | |
3528 | type, ll_mask)), | |
3529 | 0))) | |
3530 | { | |
3531 | warning ("comparison is always %s", | |
3532 | wanted_code == NE_EXPR ? "one" : "zero"); | |
3533 | ||
3534 | return convert (truth_type, | |
3535 | wanted_code == NE_EXPR | |
3536 | ? integer_one_node : integer_zero_node); | |
3537 | } | |
6d716ca8 RS |
3538 | } |
3539 | if (r_const) | |
3540 | { | |
d4453ee5 RK |
3541 | r_const = convert (type, r_const); |
3542 | r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask); | |
02103577 RK |
3543 | r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos), 0); |
3544 | if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const, | |
3545 | fold (build1 (BIT_NOT_EXPR, | |
3546 | type, rl_mask)), | |
3547 | 0))) | |
3548 | { | |
3549 | warning ("comparison is always %s", | |
3550 | wanted_code == NE_EXPR ? "one" : "zero"); | |
3551 | ||
3552 | return convert (truth_type, | |
3553 | wanted_code == NE_EXPR | |
3554 | ? integer_one_node : integer_zero_node); | |
3555 | } | |
6d716ca8 RS |
3556 | } |
3557 | ||
3558 | /* If the right sides are not constant, do the same for it. Also, | |
3559 | disallow this optimization if a size or signedness mismatch occurs | |
3560 | between the left and right sides. */ | |
3561 | if (l_const == 0) | |
3562 | { | |
3563 | if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize | |
e6a28f26 RS |
3564 | || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp |
3565 | /* Make sure the two fields on the right | |
3566 | correspond to the left without being swapped. */ | |
3567 | || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos) | |
6d716ca8 RS |
3568 | return 0; |
3569 | ||
3570 | first_bit = MIN (lr_bitpos, rr_bitpos); | |
3571 | end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize); | |
3572 | rnmode = get_best_mode (end_bit - first_bit, first_bit, | |
3573 | TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode, | |
3574 | volatilep); | |
3575 | if (rnmode == VOIDmode) | |
3576 | return 0; | |
3577 | ||
3578 | rnbitsize = GET_MODE_BITSIZE (rnmode); | |
3579 | rnbitpos = first_bit & ~ (rnbitsize - 1); | |
3580 | xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos; | |
3581 | ||
f76b9db2 ILT |
3582 | if (BYTES_BIG_ENDIAN) |
3583 | { | |
3584 | xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize; | |
3585 | xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize; | |
3586 | } | |
6d716ca8 RS |
3587 | |
3588 | lr_mask = const_binop (LSHIFT_EXPR, convert (type, lr_mask), | |
91d33e36 | 3589 | size_int (xlr_bitpos), 0); |
6d716ca8 | 3590 | rr_mask = const_binop (LSHIFT_EXPR, convert (type, rr_mask), |
91d33e36 | 3591 | size_int (xrr_bitpos), 0); |
6d716ca8 RS |
3592 | |
3593 | /* Make a mask that corresponds to both fields being compared. | |
3594 | Do this for both items being compared. If the masks agree, | |
3595 | we can do this by masking both and comparing the masked | |
3596 | results. */ | |
91d33e36 RS |
3597 | ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0); |
3598 | lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask, 0); | |
6d716ca8 RS |
3599 | if (operand_equal_p (ll_mask, lr_mask, 0) && lnbitsize == rnbitsize) |
3600 | { | |
3601 | lhs = make_bit_field_ref (ll_inner, type, lnbitsize, lnbitpos, | |
3602 | ll_unsignedp || rl_unsignedp); | |
3603 | rhs = make_bit_field_ref (lr_inner, type, rnbitsize, rnbitpos, | |
3604 | lr_unsignedp || rr_unsignedp); | |
3605 | if (! all_ones_mask_p (ll_mask, lnbitsize)) | |
3606 | { | |
3607 | lhs = build (BIT_AND_EXPR, type, lhs, ll_mask); | |
3608 | rhs = build (BIT_AND_EXPR, type, rhs, ll_mask); | |
3609 | } | |
3610 | return build (wanted_code, truth_type, lhs, rhs); | |
3611 | } | |
3612 | ||
3613 | /* There is still another way we can do something: If both pairs of | |
3614 | fields being compared are adjacent, we may be able to make a wider | |
3615 | field containing them both. */ | |
3616 | if ((ll_bitsize + ll_bitpos == rl_bitpos | |
3617 | && lr_bitsize + lr_bitpos == rr_bitpos) | |
3618 | || (ll_bitpos == rl_bitpos + rl_bitsize | |
3619 | && lr_bitpos == rr_bitpos + rr_bitsize)) | |
3620 | return build (wanted_code, truth_type, | |
3621 | make_bit_field_ref (ll_inner, type, | |
3622 | ll_bitsize + rl_bitsize, | |
3623 | MIN (ll_bitpos, rl_bitpos), | |
3624 | ll_unsignedp), | |
3625 | make_bit_field_ref (lr_inner, type, | |
3626 | lr_bitsize + rr_bitsize, | |
3627 | MIN (lr_bitpos, rr_bitpos), | |
3628 | lr_unsignedp)); | |
3629 | ||
3630 | return 0; | |
3631 | } | |
3632 | ||
3633 | /* Handle the case of comparisons with constants. If there is something in | |
3634 | common between the masks, those bits of the constants must be the same. | |
3635 | If not, the condition is always false. Test for this to avoid generating | |
3636 | incorrect code below. */ | |
91d33e36 | 3637 | result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask, 0); |
6d716ca8 | 3638 | if (! integer_zerop (result) |
91d33e36 RS |
3639 | && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const, 0), |
3640 | const_binop (BIT_AND_EXPR, result, r_const, 0)) != 1) | |
6d716ca8 RS |
3641 | { |
3642 | if (wanted_code == NE_EXPR) | |
3643 | { | |
3644 | warning ("`or' of unmatched not-equal tests is always 1"); | |
3645 | return convert (truth_type, integer_one_node); | |
3646 | } | |
3647 | else | |
3648 | { | |
3649 | warning ("`and' of mutually exclusive equal-tests is always zero"); | |
3650 | return convert (truth_type, integer_zero_node); | |
3651 | } | |
3652 | } | |
3653 | ||
3654 | /* Construct the expression we will return. First get the component | |
3655 | reference we will make. Unless the mask is all ones the width of | |
3656 | that field, perform the mask operation. Then compare with the | |
3657 | merged constant. */ | |
3658 | result = make_bit_field_ref (ll_inner, type, lnbitsize, lnbitpos, | |
3659 | ll_unsignedp || rl_unsignedp); | |
3660 | ||
91d33e36 | 3661 | ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0); |
6d716ca8 RS |
3662 | if (! all_ones_mask_p (ll_mask, lnbitsize)) |
3663 | result = build (BIT_AND_EXPR, type, result, ll_mask); | |
3664 | ||
3665 | return build (wanted_code, truth_type, result, | |
91d33e36 | 3666 | const_binop (BIT_IOR_EXPR, l_const, r_const, 0)); |
6d716ca8 RS |
3667 | } |
3668 | \f | |
b5f3b6b6 RK |
3669 | /* If T contains a COMPOUND_EXPR which was inserted merely to evaluate |
3670 | S, a SAVE_EXPR, return the expression actually being evaluated. Note | |
3671 | that we may sometimes modify the tree. */ | |
3672 | ||
3673 | static tree | |
3674 | strip_compound_expr (t, s) | |
3675 | tree t; | |
3676 | tree s; | |
3677 | { | |
b5f3b6b6 RK |
3678 | enum tree_code code = TREE_CODE (t); |
3679 | ||
3680 | /* See if this is the COMPOUND_EXPR we want to eliminate. */ | |
3681 | if (code == COMPOUND_EXPR && TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR | |
3682 | && TREE_OPERAND (TREE_OPERAND (t, 0), 0) == s) | |
3683 | return TREE_OPERAND (t, 1); | |
3684 | ||
3685 | /* See if this is a COND_EXPR or a simple arithmetic operator. We | |
3686 | don't bother handling any other types. */ | |
3687 | else if (code == COND_EXPR) | |
3688 | { | |
3689 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
3690 | TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s); | |
3691 | TREE_OPERAND (t, 2) = strip_compound_expr (TREE_OPERAND (t, 2), s); | |
3692 | } | |
3693 | else if (TREE_CODE_CLASS (code) == '1') | |
3694 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
3695 | else if (TREE_CODE_CLASS (code) == '<' | |
3696 | || TREE_CODE_CLASS (code) == '2') | |
3697 | { | |
3698 | TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s); | |
3699 | TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s); | |
3700 | } | |
3701 | ||
3702 | return t; | |
3703 | } | |
3704 | \f | |
6d716ca8 RS |
3705 | /* Perform constant folding and related simplification of EXPR. |
3706 | The related simplifications include x*1 => x, x*0 => 0, etc., | |
3707 | and application of the associative law. | |
3708 | NOP_EXPR conversions may be removed freely (as long as we | |
3709 | are careful not to change the C type of the overall expression) | |
3710 | We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR, | |
3711 | but we can constant-fold them if they have constant operands. */ | |
3712 | ||
3713 | tree | |
3714 | fold (expr) | |
3715 | tree expr; | |
3716 | { | |
3717 | register tree t = expr; | |
3718 | tree t1 = NULL_TREE; | |
c05a9b68 | 3719 | tree tem; |
6d716ca8 | 3720 | tree type = TREE_TYPE (expr); |
4e86caed | 3721 | register tree arg0 = NULL_TREE, arg1 = NULL_TREE; |
6d716ca8 RS |
3722 | register enum tree_code code = TREE_CODE (t); |
3723 | register int kind; | |
c05a9b68 | 3724 | int invert; |
6d716ca8 RS |
3725 | |
3726 | /* WINS will be nonzero when the switch is done | |
3727 | if all operands are constant. */ | |
3728 | ||
3729 | int wins = 1; | |
3730 | ||
5fd7f37d RK |
3731 | /* Don't try to process an RTL_EXPR since its operands aren't trees. |
3732 | Likewise for a SAVE_EXPR that's already been evaluated. */ | |
3733 | if (code == RTL_EXPR || (code == SAVE_EXPR && SAVE_EXPR_RTL (t)) != 0) | |
ac27d589 RK |
3734 | return t; |
3735 | ||
6d716ca8 RS |
3736 | /* Return right away if already constant. */ |
3737 | if (TREE_CONSTANT (t)) | |
3738 | { | |
3739 | if (code == CONST_DECL) | |
3740 | return DECL_INITIAL (t); | |
3741 | return t; | |
3742 | } | |
3743 | ||
3744 | kind = TREE_CODE_CLASS (code); | |
1b81aa14 RS |
3745 | if (code == NOP_EXPR || code == FLOAT_EXPR || code == CONVERT_EXPR) |
3746 | { | |
1cc1b11a RS |
3747 | tree subop; |
3748 | ||
1b81aa14 RS |
3749 | /* Special case for conversion ops that can have fixed point args. */ |
3750 | arg0 = TREE_OPERAND (t, 0); | |
3751 | ||
3752 | /* Don't use STRIP_NOPS, because signedness of argument type matters. */ | |
3753 | if (arg0 != 0) | |
3754 | STRIP_TYPE_NOPS (arg0); | |
3755 | ||
1cc1b11a RS |
3756 | if (arg0 != 0 && TREE_CODE (arg0) == COMPLEX_CST) |
3757 | subop = TREE_REALPART (arg0); | |
3758 | else | |
3759 | subop = arg0; | |
3760 | ||
3761 | if (subop != 0 && TREE_CODE (subop) != INTEGER_CST | |
1b81aa14 | 3762 | #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) |
1cc1b11a | 3763 | && TREE_CODE (subop) != REAL_CST |
1b81aa14 RS |
3764 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ |
3765 | ) | |
3766 | /* Note that TREE_CONSTANT isn't enough: | |
3767 | static var addresses are constant but we can't | |
3768 | do arithmetic on them. */ | |
3769 | wins = 0; | |
3770 | } | |
3771 | else if (kind == 'e' || kind == '<' | |
3772 | || kind == '1' || kind == '2' || kind == 'r') | |
6d716ca8 RS |
3773 | { |
3774 | register int len = tree_code_length[(int) code]; | |
3775 | register int i; | |
3776 | for (i = 0; i < len; i++) | |
3777 | { | |
3778 | tree op = TREE_OPERAND (t, i); | |
1cc1b11a | 3779 | tree subop; |
6d716ca8 RS |
3780 | |
3781 | if (op == 0) | |
3782 | continue; /* Valid for CALL_EXPR, at least. */ | |
3783 | ||
b8a91430 RK |
3784 | if (kind == '<' || code == RSHIFT_EXPR) |
3785 | { | |
3786 | /* Signedness matters here. Perhaps we can refine this | |
3787 | later. */ | |
3788 | STRIP_TYPE_NOPS (op); | |
3789 | } | |
3790 | else | |
3791 | { | |
3792 | /* Strip any conversions that don't change the mode. */ | |
3793 | STRIP_NOPS (op); | |
3794 | } | |
6d716ca8 | 3795 | |
1cc1b11a RS |
3796 | if (TREE_CODE (op) == COMPLEX_CST) |
3797 | subop = TREE_REALPART (op); | |
3798 | else | |
3799 | subop = op; | |
3800 | ||
3801 | if (TREE_CODE (subop) != INTEGER_CST | |
6d716ca8 | 3802 | #if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) |
1cc1b11a | 3803 | && TREE_CODE (subop) != REAL_CST |
6d716ca8 RS |
3804 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ |
3805 | ) | |
3806 | /* Note that TREE_CONSTANT isn't enough: | |
3807 | static var addresses are constant but we can't | |
3808 | do arithmetic on them. */ | |
3809 | wins = 0; | |
3810 | ||
3811 | if (i == 0) | |
3812 | arg0 = op; | |
3813 | else if (i == 1) | |
3814 | arg1 = op; | |
3815 | } | |
3816 | } | |
3817 | ||
3818 | /* If this is a commutative operation, and ARG0 is a constant, move it | |
3819 | to ARG1 to reduce the number of tests below. */ | |
3820 | if ((code == PLUS_EXPR || code == MULT_EXPR || code == MIN_EXPR | |
3821 | || code == MAX_EXPR || code == BIT_IOR_EXPR || code == BIT_XOR_EXPR | |
3822 | || code == BIT_AND_EXPR) | |
3823 | && (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)) | |
3824 | { | |
c05a9b68 | 3825 | tem = arg0; arg0 = arg1; arg1 = tem; |
6d716ca8 | 3826 | |
c05a9b68 RS |
3827 | tem = TREE_OPERAND (t, 0); TREE_OPERAND (t, 0) = TREE_OPERAND (t, 1); |
3828 | TREE_OPERAND (t, 1) = tem; | |
6d716ca8 RS |
3829 | } |
3830 | ||
3831 | /* Now WINS is set as described above, | |
3832 | ARG0 is the first operand of EXPR, | |
3833 | and ARG1 is the second operand (if it has more than one operand). | |
3834 | ||
3835 | First check for cases where an arithmetic operation is applied to a | |
3836 | compound, conditional, or comparison operation. Push the arithmetic | |
3837 | operation inside the compound or conditional to see if any folding | |
3838 | can then be done. Convert comparison to conditional for this purpose. | |
3839 | The also optimizes non-constant cases that used to be done in | |
96d4cf0a RK |
3840 | expand_expr. |
3841 | ||
3842 | Before we do that, see if this is a BIT_AND_EXPR or a BIT_OR_EXPR, | |
61f275ff RK |
3843 | one of the operands is a comparison and the other is a comparison, a |
3844 | BIT_AND_EXPR with the constant 1, or a truth value. In that case, the | |
3845 | code below would make the expression more complex. Change it to a | |
2df46b06 RK |
3846 | TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to |
3847 | TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */ | |
96d4cf0a | 3848 | |
2df46b06 RK |
3849 | if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR |
3850 | || code == EQ_EXPR || code == NE_EXPR) | |
61f275ff RK |
3851 | && ((truth_value_p (TREE_CODE (arg0)) |
3852 | && (truth_value_p (TREE_CODE (arg1)) | |
96d4cf0a RK |
3853 | || (TREE_CODE (arg1) == BIT_AND_EXPR |
3854 | && integer_onep (TREE_OPERAND (arg1, 1))))) | |
61f275ff RK |
3855 | || (truth_value_p (TREE_CODE (arg1)) |
3856 | && (truth_value_p (TREE_CODE (arg0)) | |
96d4cf0a RK |
3857 | || (TREE_CODE (arg0) == BIT_AND_EXPR |
3858 | && integer_onep (TREE_OPERAND (arg0, 1))))))) | |
2df46b06 RK |
3859 | { |
3860 | t = fold (build (code == BIT_AND_EXPR ? TRUTH_AND_EXPR | |
3861 | : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR | |
3862 | : TRUTH_XOR_EXPR, | |
3863 | type, arg0, arg1)); | |
3864 | ||
3865 | if (code == EQ_EXPR) | |
3866 | t = invert_truthvalue (t); | |
3867 | ||
3868 | return t; | |
3869 | } | |
96d4cf0a | 3870 | |
6d716ca8 RS |
3871 | if (TREE_CODE_CLASS (code) == '1') |
3872 | { | |
3873 | if (TREE_CODE (arg0) == COMPOUND_EXPR) | |
3874 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
3875 | fold (build1 (code, type, TREE_OPERAND (arg0, 1)))); | |
3876 | else if (TREE_CODE (arg0) == COND_EXPR) | |
b8eb43a2 RK |
3877 | { |
3878 | t = fold (build (COND_EXPR, type, TREE_OPERAND (arg0, 0), | |
3879 | fold (build1 (code, type, TREE_OPERAND (arg0, 1))), | |
3880 | fold (build1 (code, type, TREE_OPERAND (arg0, 2))))); | |
3881 | ||
3882 | /* If this was a conversion, and all we did was to move into | |
e1f56f62 RK |
3883 | inside the COND_EXPR, bring it back out. But leave it if |
3884 | it is a conversion from integer to integer and the | |
3885 | result precision is no wider than a word since such a | |
3886 | conversion is cheap and may be optimized away by combine, | |
3887 | while it couldn't if it were outside the COND_EXPR. Then return | |
3888 | so we don't get into an infinite recursion loop taking the | |
3889 | conversion out and then back in. */ | |
b8eb43a2 RK |
3890 | |
3891 | if ((code == NOP_EXPR || code == CONVERT_EXPR | |
3892 | || code == NON_LVALUE_EXPR) | |
3893 | && TREE_CODE (t) == COND_EXPR | |
3894 | && TREE_CODE (TREE_OPERAND (t, 1)) == code | |
459a2653 RK |
3895 | && TREE_CODE (TREE_OPERAND (t, 2)) == code |
3896 | && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)) | |
e1f56f62 RK |
3897 | == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 2), 0))) |
3898 | && ! (INTEGRAL_TYPE_P (TREE_TYPE (t)) | |
3899 | && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0))) | |
3900 | && TYPE_PRECISION (TREE_TYPE (t)) <= BITS_PER_WORD)) | |
b8eb43a2 RK |
3901 | t = build1 (code, type, |
3902 | build (COND_EXPR, | |
3903 | TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)), | |
3904 | TREE_OPERAND (t, 0), | |
3905 | TREE_OPERAND (TREE_OPERAND (t, 1), 0), | |
3906 | TREE_OPERAND (TREE_OPERAND (t, 2), 0))); | |
3907 | return t; | |
3908 | } | |
6d716ca8 RS |
3909 | else if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<') |
3910 | return fold (build (COND_EXPR, type, arg0, | |
3911 | fold (build1 (code, type, integer_one_node)), | |
3912 | fold (build1 (code, type, integer_zero_node)))); | |
3913 | } | |
96d4cf0a RK |
3914 | else if (TREE_CODE_CLASS (code) == '2' |
3915 | || TREE_CODE_CLASS (code) == '<') | |
6d716ca8 RS |
3916 | { |
3917 | if (TREE_CODE (arg1) == COMPOUND_EXPR) | |
3918 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), | |
96d4cf0a RK |
3919 | fold (build (code, type, |
3920 | arg0, TREE_OPERAND (arg1, 1)))); | |
f0eebf28 RK |
3921 | else if ((TREE_CODE (arg1) == COND_EXPR |
3922 | || (TREE_CODE_CLASS (TREE_CODE (arg1)) == '<' | |
3923 | && TREE_CODE_CLASS (code) != '<')) | |
3924 | && (! TREE_SIDE_EFFECTS (arg0) || current_function_decl != 0)) | |
6d716ca8 RS |
3925 | { |
3926 | tree test, true_value, false_value; | |
f5963e61 | 3927 | tree lhs = 0, rhs = 0; |
6d716ca8 RS |
3928 | |
3929 | if (TREE_CODE (arg1) == COND_EXPR) | |
3930 | { | |
3931 | test = TREE_OPERAND (arg1, 0); | |
3932 | true_value = TREE_OPERAND (arg1, 1); | |
3933 | false_value = TREE_OPERAND (arg1, 2); | |
3934 | } | |
3935 | else | |
3936 | { | |
25216284 | 3937 | tree testtype = TREE_TYPE (arg1); |
6d716ca8 | 3938 | test = arg1; |
25216284 RK |
3939 | true_value = convert (testtype, integer_one_node); |
3940 | false_value = convert (testtype, integer_zero_node); | |
6d716ca8 RS |
3941 | } |
3942 | ||
96d4cf0a RK |
3943 | /* If ARG0 is complex we want to make sure we only evaluate |
3944 | it once. Though this is only required if it is volatile, it | |
3945 | might be more efficient even if it is not. However, if we | |
3946 | succeed in folding one part to a constant, we do not need | |
3947 | to make this SAVE_EXPR. Since we do this optimization | |
3948 | primarily to see if we do end up with constant and this | |
9faa82d8 | 3949 | SAVE_EXPR interferes with later optimizations, suppressing |
f5963e61 | 3950 | it when we can is important. |
96d4cf0a | 3951 | |
f5963e61 JL |
3952 | If we are not in a function, we can't make a SAVE_EXPR, so don't |
3953 | try to do so. Don't try to see if the result is a constant | |
3954 | if an arm is a COND_EXPR since we get exponential behavior | |
3955 | in that case. */ | |
3956 | ||
3957 | if (TREE_CODE (arg0) != SAVE_EXPR && ! TREE_CONSTANT (arg0) | |
3958 | && current_function_decl != 0 | |
b5f3b6b6 RK |
3959 | && ((TREE_CODE (arg0) != VAR_DECL |
3960 | && TREE_CODE (arg0) != PARM_DECL) | |
3961 | || TREE_SIDE_EFFECTS (arg0))) | |
96d4cf0a | 3962 | { |
f5963e61 JL |
3963 | if (TREE_CODE (true_value) != COND_EXPR) |
3964 | lhs = fold (build (code, type, arg0, true_value)); | |
96d4cf0a | 3965 | |
f5963e61 JL |
3966 | if (TREE_CODE (false_value) != COND_EXPR) |
3967 | rhs = fold (build (code, type, arg0, false_value)); | |
96d4cf0a | 3968 | |
f5963e61 JL |
3969 | if ((lhs == 0 || ! TREE_CONSTANT (lhs)) |
3970 | && (rhs == 0 || !TREE_CONSTANT (rhs))) | |
3971 | arg0 = save_expr (arg0), lhs = rhs = 0; | |
96d4cf0a RK |
3972 | } |
3973 | ||
f5963e61 JL |
3974 | if (lhs == 0) |
3975 | lhs = fold (build (code, type, arg0, true_value)); | |
3976 | if (rhs == 0) | |
3977 | rhs = fold (build (code, type, arg0, false_value)); | |
3978 | ||
3979 | test = fold (build (COND_EXPR, type, test, lhs, rhs)); | |
3980 | ||
6d716ca8 RS |
3981 | if (TREE_CODE (arg0) == SAVE_EXPR) |
3982 | return build (COMPOUND_EXPR, type, | |
b5f3b6b6 RK |
3983 | convert (void_type_node, arg0), |
3984 | strip_compound_expr (test, arg0)); | |
6d716ca8 RS |
3985 | else |
3986 | return convert (type, test); | |
3987 | } | |
3988 | ||
3989 | else if (TREE_CODE (arg0) == COMPOUND_EXPR) | |
3990 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
3991 | fold (build (code, type, TREE_OPERAND (arg0, 1), arg1))); | |
f0eebf28 RK |
3992 | else if ((TREE_CODE (arg0) == COND_EXPR |
3993 | || (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' | |
3994 | && TREE_CODE_CLASS (code) != '<')) | |
3995 | && (! TREE_SIDE_EFFECTS (arg1) || current_function_decl != 0)) | |
6d716ca8 RS |
3996 | { |
3997 | tree test, true_value, false_value; | |
f5963e61 | 3998 | tree lhs = 0, rhs = 0; |
6d716ca8 RS |
3999 | |
4000 | if (TREE_CODE (arg0) == COND_EXPR) | |
4001 | { | |
4002 | test = TREE_OPERAND (arg0, 0); | |
4003 | true_value = TREE_OPERAND (arg0, 1); | |
4004 | false_value = TREE_OPERAND (arg0, 2); | |
4005 | } | |
4006 | else | |
4007 | { | |
25216284 | 4008 | tree testtype = TREE_TYPE (arg0); |
6d716ca8 | 4009 | test = arg0; |
25216284 RK |
4010 | true_value = convert (testtype, integer_one_node); |
4011 | false_value = convert (testtype, integer_zero_node); | |
6d716ca8 RS |
4012 | } |
4013 | ||
f5963e61 JL |
4014 | if (TREE_CODE (arg1) != SAVE_EXPR && ! TREE_CONSTANT (arg0) |
4015 | && current_function_decl != 0 | |
b5f3b6b6 RK |
4016 | && ((TREE_CODE (arg1) != VAR_DECL |
4017 | && TREE_CODE (arg1) != PARM_DECL) | |
4018 | || TREE_SIDE_EFFECTS (arg1))) | |
96d4cf0a | 4019 | { |
f5963e61 JL |
4020 | if (TREE_CODE (true_value) != COND_EXPR) |
4021 | lhs = fold (build (code, type, true_value, arg1)); | |
96d4cf0a | 4022 | |
f5963e61 JL |
4023 | if (TREE_CODE (false_value) != COND_EXPR) |
4024 | rhs = fold (build (code, type, false_value, arg1)); | |
96d4cf0a | 4025 | |
f5963e61 JL |
4026 | if ((lhs == 0 || ! TREE_CONSTANT (lhs)) |
4027 | && (rhs == 0 || !TREE_CONSTANT (rhs))) | |
4028 | arg1 = save_expr (arg1), lhs = rhs = 0; | |
96d4cf0a RK |
4029 | } |
4030 | ||
f5963e61 JL |
4031 | if (lhs == 0) |
4032 | lhs = fold (build (code, type, true_value, arg1)); | |
4033 | ||
4034 | if (rhs == 0) | |
4035 | rhs = fold (build (code, type, false_value, arg1)); | |
4036 | ||
4037 | test = fold (build (COND_EXPR, type, test, lhs, rhs)); | |
6d716ca8 RS |
4038 | if (TREE_CODE (arg1) == SAVE_EXPR) |
4039 | return build (COMPOUND_EXPR, type, | |
b5f3b6b6 RK |
4040 | convert (void_type_node, arg1), |
4041 | strip_compound_expr (test, arg1)); | |
6d716ca8 RS |
4042 | else |
4043 | return convert (type, test); | |
4044 | } | |
4045 | } | |
c05a9b68 RS |
4046 | else if (TREE_CODE_CLASS (code) == '<' |
4047 | && TREE_CODE (arg0) == COMPOUND_EXPR) | |
4048 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), | |
4049 | fold (build (code, type, TREE_OPERAND (arg0, 1), arg1))); | |
4050 | else if (TREE_CODE_CLASS (code) == '<' | |
4051 | && TREE_CODE (arg1) == COMPOUND_EXPR) | |
4052 | return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), | |
4053 | fold (build (code, type, arg0, TREE_OPERAND (arg1, 1)))); | |
6d716ca8 RS |
4054 | |
4055 | switch (code) | |
4056 | { | |
4057 | case INTEGER_CST: | |
4058 | case REAL_CST: | |
4059 | case STRING_CST: | |
4060 | case COMPLEX_CST: | |
4061 | case CONSTRUCTOR: | |
4062 | return t; | |
4063 | ||
4064 | case CONST_DECL: | |
4065 | return fold (DECL_INITIAL (t)); | |
4066 | ||
4067 | case NOP_EXPR: | |
4068 | case FLOAT_EXPR: | |
4069 | case CONVERT_EXPR: | |
4070 | case FIX_TRUNC_EXPR: | |
4071 | /* Other kinds of FIX are not handled properly by fold_convert. */ | |
33558beb | 4072 | |
e1f56f62 RK |
4073 | if (TREE_TYPE (TREE_OPERAND (t, 0)) == TREE_TYPE (t)) |
4074 | return TREE_OPERAND (t, 0); | |
4075 | ||
7e139075 RK |
4076 | /* Handle cases of two conversions in a row. */ |
4077 | if (TREE_CODE (TREE_OPERAND (t, 0)) == NOP_EXPR | |
4078 | || TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR) | |
4079 | { | |
4080 | tree inside_type = TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
4081 | tree inter_type = TREE_TYPE (TREE_OPERAND (t, 0)); | |
4082 | tree final_type = TREE_TYPE (t); | |
4083 | int inside_int = INTEGRAL_TYPE_P (inside_type); | |
7f0b305c | 4084 | int inside_ptr = POINTER_TYPE_P (inside_type); |
7e139075 RK |
4085 | int inside_float = FLOAT_TYPE_P (inside_type); |
4086 | int inside_prec = TYPE_PRECISION (inside_type); | |
4087 | int inside_unsignedp = TREE_UNSIGNED (inside_type); | |
4088 | int inter_int = INTEGRAL_TYPE_P (inter_type); | |
7f0b305c | 4089 | int inter_ptr = POINTER_TYPE_P (inter_type); |
7e139075 RK |
4090 | int inter_float = FLOAT_TYPE_P (inter_type); |
4091 | int inter_prec = TYPE_PRECISION (inter_type); | |
4092 | int inter_unsignedp = TREE_UNSIGNED (inter_type); | |
4093 | int final_int = INTEGRAL_TYPE_P (final_type); | |
7f0b305c | 4094 | int final_ptr = POINTER_TYPE_P (final_type); |
7e139075 RK |
4095 | int final_float = FLOAT_TYPE_P (final_type); |
4096 | int final_prec = TYPE_PRECISION (final_type); | |
4097 | int final_unsignedp = TREE_UNSIGNED (final_type); | |
4098 | ||
4099 | /* In addition to the cases of two conversions in a row | |
4100 | handled below, if we are converting something to its own | |
4101 | type via an object of identical or wider precision, neither | |
4102 | conversion is needed. */ | |
4103 | if (inside_type == final_type | |
4104 | && ((inter_int && final_int) || (inter_float && final_float)) | |
4105 | && inter_prec >= final_prec) | |
4106 | return TREE_OPERAND (TREE_OPERAND (t, 0), 0); | |
4107 | ||
4108 | /* Likewise, if the intermediate and final types are either both | |
4109 | float or both integer, we don't need the middle conversion if | |
4110 | it is wider than the final type and doesn't change the signedness | |
7f0b305c | 4111 | (for integers). Avoid this if the final type is a pointer |
410d3f5d RK |
4112 | since then we sometimes need the inner conversion. Likewise if |
4113 | the outer has a precision not equal to the size of its mode. */ | |
7e139075 RK |
4114 | if ((((inter_int || inter_ptr) && (inside_int || inside_ptr)) |
4115 | || (inter_float && inside_float)) | |
4116 | && inter_prec >= inside_prec | |
7f0b305c | 4117 | && (inter_float || inter_unsignedp == inside_unsignedp) |
410d3f5d RK |
4118 | && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type)) |
4119 | && TYPE_MODE (final_type) == TYPE_MODE (inter_type)) | |
7f0b305c | 4120 | && ! final_ptr) |
7e139075 RK |
4121 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
4122 | ||
ba3ad5e0 PDM |
4123 | /* If we have a sign-extension of a zero-extended value, we can |
4124 | replace that by a single zero-extension. */ | |
4125 | if (inside_int && inter_int && final_int | |
4126 | && inside_prec < inter_prec && inter_prec < final_prec | |
4127 | && inside_unsignedp && !inter_unsignedp) | |
4128 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); | |
4129 | ||
7e139075 RK |
4130 | /* Two conversions in a row are not needed unless: |
4131 | - some conversion is floating-point (overstrict for now), or | |
4132 | - the intermediate type is narrower than both initial and | |
4133 | final, or | |
4134 | - the intermediate type and innermost type differ in signedness, | |
4135 | and the outermost type is wider than the intermediate, or | |
4136 | - the initial type is a pointer type and the precisions of the | |
4137 | intermediate and final types differ, or | |
4138 | - the final type is a pointer type and the precisions of the | |
4139 | initial and intermediate types differ. */ | |
4140 | if (! inside_float && ! inter_float && ! final_float | |
4141 | && (inter_prec > inside_prec || inter_prec > final_prec) | |
4142 | && ! (inside_int && inter_int | |
4143 | && inter_unsignedp != inside_unsignedp | |
4144 | && inter_prec < final_prec) | |
4145 | && ((inter_unsignedp && inter_prec > inside_prec) | |
4146 | == (final_unsignedp && final_prec > inter_prec)) | |
4147 | && ! (inside_ptr && inter_prec != final_prec) | |
410d3f5d RK |
4148 | && ! (final_ptr && inside_prec != inter_prec) |
4149 | && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type)) | |
4150 | && TYPE_MODE (final_type) == TYPE_MODE (inter_type)) | |
4151 | && ! final_ptr) | |
7e139075 RK |
4152 | return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0)); |
4153 | } | |
6d716ca8 RS |
4154 | |
4155 | if (TREE_CODE (TREE_OPERAND (t, 0)) == MODIFY_EXPR | |
d8f6dbb9 RS |
4156 | && TREE_CONSTANT (TREE_OPERAND (TREE_OPERAND (t, 0), 1)) |
4157 | /* Detect assigning a bitfield. */ | |
4158 | && !(TREE_CODE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)) == COMPONENT_REF | |
4159 | && DECL_BIT_FIELD (TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (t, 0), 0), 1)))) | |
6d716ca8 | 4160 | { |
d8f6dbb9 | 4161 | /* Don't leave an assignment inside a conversion |
f72aed24 | 4162 | unless assigning a bitfield. */ |
6d716ca8 RS |
4163 | tree prev = TREE_OPERAND (t, 0); |
4164 | TREE_OPERAND (t, 0) = TREE_OPERAND (prev, 1); | |
4165 | /* First do the assignment, then return converted constant. */ | |
4166 | t = build (COMPOUND_EXPR, TREE_TYPE (t), prev, fold (t)); | |
4167 | TREE_USED (t) = 1; | |
4168 | return t; | |
4169 | } | |
4170 | if (!wins) | |
4171 | { | |
4172 | TREE_CONSTANT (t) = TREE_CONSTANT (arg0); | |
4173 | return t; | |
4174 | } | |
4175 | return fold_convert (t, arg0); | |
4176 | ||
4177 | #if 0 /* This loses on &"foo"[0]. */ | |
4178 | case ARRAY_REF: | |
4179 | { | |
4180 | int i; | |
4181 | ||
4182 | /* Fold an expression like: "foo"[2] */ | |
4183 | if (TREE_CODE (arg0) == STRING_CST | |
4184 | && TREE_CODE (arg1) == INTEGER_CST | |
4185 | && !TREE_INT_CST_HIGH (arg1) | |
4186 | && (i = TREE_INT_CST_LOW (arg1)) < TREE_STRING_LENGTH (arg0)) | |
4187 | { | |
4188 | t = build_int_2 (TREE_STRING_POINTER (arg0)[i], 0); | |
4189 | TREE_TYPE (t) = TREE_TYPE (TREE_TYPE (arg0)); | |
ef2bf0c0 | 4190 | force_fit_type (t, 0); |
6d716ca8 RS |
4191 | } |
4192 | } | |
4193 | return t; | |
4194 | #endif /* 0 */ | |
4195 | ||
e082358b JM |
4196 | case COMPONENT_REF: |
4197 | if (TREE_CODE (arg0) == CONSTRUCTOR) | |
3ac4f0e6 JM |
4198 | { |
4199 | tree m = purpose_member (arg1, CONSTRUCTOR_ELTS (arg0)); | |
4200 | if (m) | |
4201 | t = TREE_VALUE (m); | |
4202 | } | |
e082358b JM |
4203 | return t; |
4204 | ||
6d716ca8 RS |
4205 | case RANGE_EXPR: |
4206 | TREE_CONSTANT (t) = wins; | |
4207 | return t; | |
4208 | ||
4209 | case NEGATE_EXPR: | |
4210 | if (wins) | |
4211 | { | |
4212 | if (TREE_CODE (arg0) == INTEGER_CST) | |
4213 | { | |
fe3e8e40 RS |
4214 | HOST_WIDE_INT low, high; |
4215 | int overflow = neg_double (TREE_INT_CST_LOW (arg0), | |
4216 | TREE_INT_CST_HIGH (arg0), | |
4217 | &low, &high); | |
4218 | t = build_int_2 (low, high); | |
6d716ca8 | 4219 | TREE_TYPE (t) = type; |
dc3907c5 PE |
4220 | TREE_OVERFLOW (t) |
4221 | = (TREE_OVERFLOW (arg0) | |
0c9cabe7 | 4222 | | force_fit_type (t, overflow && !TREE_UNSIGNED (type))); |
dc3907c5 PE |
4223 | TREE_CONSTANT_OVERFLOW (t) |
4224 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0); | |
6d716ca8 RS |
4225 | } |
4226 | else if (TREE_CODE (arg0) == REAL_CST) | |
4227 | t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0))); | |
6d716ca8 RS |
4228 | } |
4229 | else if (TREE_CODE (arg0) == NEGATE_EXPR) | |
4230 | return TREE_OPERAND (arg0, 0); | |
4231 | ||
4232 | /* Convert - (a - b) to (b - a) for non-floating-point. */ | |
7178e3af | 4233 | else if (TREE_CODE (arg0) == MINUS_EXPR && ! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
4234 | return build (MINUS_EXPR, type, TREE_OPERAND (arg0, 1), |
4235 | TREE_OPERAND (arg0, 0)); | |
4236 | ||
4237 | return t; | |
4238 | ||
4239 | case ABS_EXPR: | |
4240 | if (wins) | |
4241 | { | |
4242 | if (TREE_CODE (arg0) == INTEGER_CST) | |
4243 | { | |
4244 | if (! TREE_UNSIGNED (type) | |
4245 | && TREE_INT_CST_HIGH (arg0) < 0) | |
4246 | { | |
2a23183e RS |
4247 | HOST_WIDE_INT low, high; |
4248 | int overflow = neg_double (TREE_INT_CST_LOW (arg0), | |
4249 | TREE_INT_CST_HIGH (arg0), | |
4250 | &low, &high); | |
4251 | t = build_int_2 (low, high); | |
4252 | TREE_TYPE (t) = type; | |
dc3907c5 PE |
4253 | TREE_OVERFLOW (t) |
4254 | = (TREE_OVERFLOW (arg0) | |
e0f776fb | 4255 | | force_fit_type (t, overflow)); |
dc3907c5 PE |
4256 | TREE_CONSTANT_OVERFLOW (t) |
4257 | = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0); | |
6d716ca8 RS |
4258 | } |
4259 | } | |
4260 | else if (TREE_CODE (arg0) == REAL_CST) | |
4261 | { | |
c05a9b68 | 4262 | if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0))) |
6d716ca8 RS |
4263 | t = build_real (type, |
4264 | REAL_VALUE_NEGATE (TREE_REAL_CST (arg0))); | |
4265 | } | |
6d716ca8 RS |
4266 | } |
4267 | else if (TREE_CODE (arg0) == ABS_EXPR || TREE_CODE (arg0) == NEGATE_EXPR) | |
4268 | return build1 (ABS_EXPR, type, TREE_OPERAND (arg0, 0)); | |
4269 | return t; | |
4270 | ||
551064b1 RS |
4271 | case CONJ_EXPR: |
4272 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) | |
4273 | return arg0; | |
4274 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
4275 | return build (COMPLEX_EXPR, TREE_TYPE (arg0), | |
4276 | TREE_OPERAND (arg0, 0), | |
4277 | fold (build1 (NEGATE_EXPR, | |
4278 | TREE_TYPE (TREE_TYPE (arg0)), | |
4279 | TREE_OPERAND (arg0, 1)))); | |
4280 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
214d5b84 | 4281 | return build_complex (type, TREE_OPERAND (arg0, 0), |
551064b1 RS |
4282 | fold (build1 (NEGATE_EXPR, |
4283 | TREE_TYPE (TREE_TYPE (arg0)), | |
4284 | TREE_OPERAND (arg0, 1)))); | |
4285 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
4286 | return fold (build (TREE_CODE (arg0), type, | |
4287 | fold (build1 (CONJ_EXPR, type, | |
4288 | TREE_OPERAND (arg0, 0))), | |
4289 | fold (build1 (CONJ_EXPR, | |
4290 | type, TREE_OPERAND (arg0, 1))))); | |
4291 | else if (TREE_CODE (arg0) == CONJ_EXPR) | |
4292 | return TREE_OPERAND (arg0, 0); | |
4293 | return t; | |
4294 | ||
6d716ca8 RS |
4295 | case BIT_NOT_EXPR: |
4296 | if (wins) | |
4297 | { | |
380ff34a RK |
4298 | t = build_int_2 (~ TREE_INT_CST_LOW (arg0), |
4299 | ~ TREE_INT_CST_HIGH (arg0)); | |
6d716ca8 | 4300 | TREE_TYPE (t) = type; |
e0f776fb | 4301 | force_fit_type (t, 0); |
dc3907c5 | 4302 | TREE_OVERFLOW (t) = TREE_OVERFLOW (arg0); |
fe3e8e40 | 4303 | TREE_CONSTANT_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (arg0); |
6d716ca8 RS |
4304 | } |
4305 | else if (TREE_CODE (arg0) == BIT_NOT_EXPR) | |
4306 | return TREE_OPERAND (arg0, 0); | |
4307 | return t; | |
4308 | ||
4309 | case PLUS_EXPR: | |
4310 | /* A + (-B) -> A - B */ | |
4311 | if (TREE_CODE (arg1) == NEGATE_EXPR) | |
4312 | return fold (build (MINUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0))); | |
7178e3af | 4313 | else if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
4314 | { |
4315 | if (integer_zerop (arg1)) | |
4316 | return non_lvalue (convert (type, arg0)); | |
4317 | ||
4318 | /* If we are adding two BIT_AND_EXPR's, both of which are and'ing | |
4319 | with a constant, and the two constants have no bits in common, | |
4320 | we should treat this as a BIT_IOR_EXPR since this may produce more | |
4321 | simplifications. */ | |
4322 | if (TREE_CODE (arg0) == BIT_AND_EXPR | |
4323 | && TREE_CODE (arg1) == BIT_AND_EXPR | |
4324 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
4325 | && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST | |
4326 | && integer_zerop (const_binop (BIT_AND_EXPR, | |
4327 | TREE_OPERAND (arg0, 1), | |
91d33e36 | 4328 | TREE_OPERAND (arg1, 1), 0))) |
6d716ca8 RS |
4329 | { |
4330 | code = BIT_IOR_EXPR; | |
4331 | goto bit_ior; | |
4332 | } | |
6a96fcb4 RK |
4333 | |
4334 | /* (A * C) + (B * C) -> (A+B) * C. Since we are most concerned | |
4335 | about the case where C is a constant, just try one of the | |
4336 | four possibilities. */ | |
4337 | ||
4338 | if (TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (arg1) == MULT_EXPR | |
4339 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
4340 | TREE_OPERAND (arg1, 1), 0)) | |
4341 | return fold (build (MULT_EXPR, type, | |
4342 | fold (build (PLUS_EXPR, type, | |
4343 | TREE_OPERAND (arg0, 0), | |
4344 | TREE_OPERAND (arg1, 0))), | |
4345 | TREE_OPERAND (arg0, 1))); | |
6d716ca8 RS |
4346 | } |
4347 | /* In IEEE floating point, x+0 may not equal x. */ | |
996c63d3 RK |
4348 | else if ((TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
4349 | || flag_fast_math) | |
6d716ca8 RS |
4350 | && real_zerop (arg1)) |
4351 | return non_lvalue (convert (type, arg0)); | |
4352 | associate: | |
4353 | /* In most languages, can't associate operations on floats | |
4354 | through parentheses. Rather than remember where the parentheses | |
e9aaa5a5 RK |
4355 | were, we don't associate floats at all. It shouldn't matter much. |
4356 | However, associating multiplications is only very slightly | |
4357 | inaccurate, so do that if -ffast-math is specified. */ | |
4358 | if (FLOAT_TYPE_P (type) | |
4359 | && ! (flag_fast_math && code == MULT_EXPR)) | |
6d716ca8 | 4360 | goto binary; |
e9aaa5a5 | 4361 | |
6d716ca8 RS |
4362 | /* The varsign == -1 cases happen only for addition and subtraction. |
4363 | It says that the arg that was split was really CON minus VAR. | |
4364 | The rest of the code applies to all associative operations. */ | |
4365 | if (!wins) | |
4366 | { | |
c05a9b68 | 4367 | tree var, con; |
6d716ca8 RS |
4368 | int varsign; |
4369 | ||
4370 | if (split_tree (arg0, code, &var, &con, &varsign)) | |
4371 | { | |
4372 | if (varsign == -1) | |
4373 | { | |
4374 | /* EXPR is (CON-VAR) +- ARG1. */ | |
4375 | /* If it is + and VAR==ARG1, return just CONST. */ | |
4376 | if (code == PLUS_EXPR && operand_equal_p (var, arg1, 0)) | |
4377 | return convert (TREE_TYPE (t), con); | |
4378 | ||
ca86a57a RK |
4379 | /* If ARG0 is a constant, don't change things around; |
4380 | instead keep all the constant computations together. */ | |
4381 | ||
4382 | if (TREE_CONSTANT (arg0)) | |
4383 | return t; | |
4384 | ||
6d716ca8 | 4385 | /* Otherwise return (CON +- ARG1) - VAR. */ |
cd7ece66 RK |
4386 | t = build (MINUS_EXPR, type, |
4387 | fold (build (code, type, con, arg1)), var); | |
6d716ca8 RS |
4388 | } |
4389 | else | |
4390 | { | |
4391 | /* EXPR is (VAR+CON) +- ARG1. */ | |
4392 | /* If it is - and VAR==ARG1, return just CONST. */ | |
4393 | if (code == MINUS_EXPR && operand_equal_p (var, arg1, 0)) | |
4394 | return convert (TREE_TYPE (t), con); | |
4395 | ||
ca86a57a RK |
4396 | /* If ARG0 is a constant, don't change things around; |
4397 | instead keep all the constant computations together. */ | |
4398 | ||
4399 | if (TREE_CONSTANT (arg0)) | |
4400 | return t; | |
4401 | ||
6d716ca8 | 4402 | /* Otherwise return VAR +- (ARG1 +- CON). */ |
cd7ece66 RK |
4403 | tem = fold (build (code, type, arg1, con)); |
4404 | t = build (code, type, var, tem); | |
4405 | ||
6d716ca8 RS |
4406 | if (integer_zerop (tem) |
4407 | && (code == PLUS_EXPR || code == MINUS_EXPR)) | |
4408 | return convert (type, var); | |
4409 | /* If we have x +/- (c - d) [c an explicit integer] | |
4410 | change it to x -/+ (d - c) since if d is relocatable | |
4411 | then the latter can be a single immediate insn | |
4412 | and the former cannot. */ | |
4413 | if (TREE_CODE (tem) == MINUS_EXPR | |
4414 | && TREE_CODE (TREE_OPERAND (tem, 0)) == INTEGER_CST) | |
4415 | { | |
4416 | tree tem1 = TREE_OPERAND (tem, 1); | |
4417 | TREE_OPERAND (tem, 1) = TREE_OPERAND (tem, 0); | |
4418 | TREE_OPERAND (tem, 0) = tem1; | |
4419 | TREE_SET_CODE (t, | |
4420 | (code == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR)); | |
4421 | } | |
4422 | } | |
4423 | return t; | |
4424 | } | |
4425 | ||
4426 | if (split_tree (arg1, code, &var, &con, &varsign)) | |
4427 | { | |
cc5edac6 RK |
4428 | if (TREE_CONSTANT (arg1)) |
4429 | return t; | |
4430 | ||
4431 | if (varsign == -1) | |
4432 | TREE_SET_CODE (t, | |
4433 | (code == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR)); | |
4434 | ||
6d716ca8 | 4435 | /* EXPR is ARG0 +- (CON +- VAR). */ |
6d716ca8 RS |
4436 | if (TREE_CODE (t) == MINUS_EXPR |
4437 | && operand_equal_p (var, arg0, 0)) | |
4438 | { | |
4439 | /* If VAR and ARG0 cancel, return just CON or -CON. */ | |
4440 | if (code == PLUS_EXPR) | |
4441 | return convert (TREE_TYPE (t), con); | |
4442 | return fold (build1 (NEGATE_EXPR, TREE_TYPE (t), | |
4443 | convert (TREE_TYPE (t), con))); | |
4444 | } | |
cc5edac6 | 4445 | |
cd7ece66 RK |
4446 | t = build (TREE_CODE (t), type, |
4447 | fold (build (code, TREE_TYPE (t), arg0, con)), var); | |
4448 | ||
6d716ca8 RS |
4449 | if (integer_zerop (TREE_OPERAND (t, 0)) |
4450 | && TREE_CODE (t) == PLUS_EXPR) | |
4451 | return convert (TREE_TYPE (t), var); | |
4452 | return t; | |
4453 | } | |
4454 | } | |
4455 | binary: | |
4456 | #if defined (REAL_IS_NOT_DOUBLE) && ! defined (REAL_ARITHMETIC) | |
4457 | if (TREE_CODE (arg1) == REAL_CST) | |
4458 | return t; | |
4459 | #endif /* REAL_IS_NOT_DOUBLE, and no REAL_ARITHMETIC */ | |
4460 | if (wins) | |
91d33e36 | 4461 | t1 = const_binop (code, arg0, arg1, 0); |
6d716ca8 RS |
4462 | if (t1 != NULL_TREE) |
4463 | { | |
4464 | /* The return value should always have | |
4465 | the same type as the original expression. */ | |
380ff34a RK |
4466 | if (TREE_TYPE (t1) != TREE_TYPE (t)) |
4467 | t1 = convert (TREE_TYPE (t), t1); | |
4468 | ||
6d716ca8 RS |
4469 | return t1; |
4470 | } | |
4471 | return t; | |
4472 | ||
4473 | case MINUS_EXPR: | |
7178e3af | 4474 | if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
4475 | { |
4476 | if (! wins && integer_zerop (arg0)) | |
4477 | return build1 (NEGATE_EXPR, type, arg1); | |
4478 | if (integer_zerop (arg1)) | |
4479 | return non_lvalue (convert (type, arg0)); | |
6a96fcb4 RK |
4480 | |
4481 | /* (A * C) - (B * C) -> (A-B) * C. Since we are most concerned | |
4482 | about the case where C is a constant, just try one of the | |
4483 | four possibilities. */ | |
4484 | ||
4485 | if (TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (arg1) == MULT_EXPR | |
4486 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
4487 | TREE_OPERAND (arg1, 1), 0)) | |
4488 | return fold (build (MULT_EXPR, type, | |
4489 | fold (build (MINUS_EXPR, type, | |
4490 | TREE_OPERAND (arg0, 0), | |
4491 | TREE_OPERAND (arg1, 0))), | |
4492 | TREE_OPERAND (arg0, 1))); | |
6d716ca8 RS |
4493 | } |
4494 | /* Convert A - (-B) to A + B. */ | |
4495 | else if (TREE_CODE (arg1) == NEGATE_EXPR) | |
4496 | return fold (build (PLUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0))); | |
fab446b8 RK |
4497 | |
4498 | else if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT | |
4499 | || flag_fast_math) | |
6d716ca8 | 4500 | { |
c05a9b68 | 4501 | /* Except with IEEE floating point, 0-x equals -x. */ |
6d716ca8 RS |
4502 | if (! wins && real_zerop (arg0)) |
4503 | return build1 (NEGATE_EXPR, type, arg1); | |
c05a9b68 RS |
4504 | /* Except with IEEE floating point, x-0 equals x. */ |
4505 | if (real_zerop (arg1)) | |
6d716ca8 | 4506 | return non_lvalue (convert (type, arg0)); |
fab446b8 | 4507 | } |
a6acbe15 | 4508 | |
fab446b8 RK |
4509 | /* Fold &x - &x. This can happen from &x.foo - &x. |
4510 | This is unsafe for certain floats even in non-IEEE formats. | |
4511 | In IEEE, it is unsafe because it does wrong for NaNs. | |
4512 | Also note that operand_equal_p is always false if an operand | |
4513 | is volatile. */ | |
4514 | ||
59d90212 JW |
4515 | if ((! FLOAT_TYPE_P (type) || flag_fast_math) |
4516 | && operand_equal_p (arg0, arg1, 0)) | |
fab446b8 | 4517 | return convert (type, integer_zero_node); |
a6acbe15 | 4518 | |
6d716ca8 RS |
4519 | goto associate; |
4520 | ||
4521 | case MULT_EXPR: | |
7178e3af | 4522 | if (! FLOAT_TYPE_P (type)) |
6d716ca8 RS |
4523 | { |
4524 | if (integer_zerop (arg1)) | |
4525 | return omit_one_operand (type, arg1, arg0); | |
4526 | if (integer_onep (arg1)) | |
4527 | return non_lvalue (convert (type, arg0)); | |
4528 | ||
b9b5c1b3 RK |
4529 | /* ((A / C) * C) is A if the division is an |
4530 | EXACT_DIV_EXPR. Since C is normally a constant, | |
4531 | just check for one of the four possibilities. */ | |
4532 | ||
4533 | if (TREE_CODE (arg0) == EXACT_DIV_EXPR | |
4534 | && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)) | |
4535 | return TREE_OPERAND (arg0, 0); | |
4536 | ||
6d716ca8 RS |
4537 | /* (a * (1 << b)) is (a << b) */ |
4538 | if (TREE_CODE (arg1) == LSHIFT_EXPR | |
4539 | && integer_onep (TREE_OPERAND (arg1, 0))) | |
4540 | return fold (build (LSHIFT_EXPR, type, arg0, | |
4541 | TREE_OPERAND (arg1, 1))); | |
4542 | if (TREE_CODE (arg0) == LSHIFT_EXPR | |
4543 | && integer_onep (TREE_OPERAND (arg0, 0))) | |
4544 | return fold (build (LSHIFT_EXPR, type, arg1, | |
4545 | TREE_OPERAND (arg0, 1))); | |
4546 | } | |
6d716ca8 RS |
4547 | else |
4548 | { | |
c05a9b68 | 4549 | /* x*0 is 0, except for IEEE floating point. */ |
fab446b8 RK |
4550 | if ((TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
4551 | || flag_fast_math) | |
6d716ca8 RS |
4552 | && real_zerop (arg1)) |
4553 | return omit_one_operand (type, arg1, arg0); | |
c05a9b68 | 4554 | /* In IEEE floating point, x*1 is not equivalent to x for snans. |
6d716ca8 RS |
4555 | However, ANSI says we can drop signals, |
4556 | so we can do this anyway. */ | |
4557 | if (real_onep (arg1)) | |
4558 | return non_lvalue (convert (type, arg0)); | |
4559 | /* x*2 is x+x */ | |
f0eebf28 | 4560 | if (! wins && real_twop (arg1) && current_function_decl != 0) |
6d716ca8 RS |
4561 | { |
4562 | tree arg = save_expr (arg0); | |
4563 | return build (PLUS_EXPR, type, arg, arg); | |
4564 | } | |
4565 | } | |
4566 | goto associate; | |
4567 | ||
4568 | case BIT_IOR_EXPR: | |
4569 | bit_ior: | |
65d8b1ce RK |
4570 | { |
4571 | register enum tree_code code0, code1; | |
4572 | ||
6d716ca8 RS |
4573 | if (integer_all_onesp (arg1)) |
4574 | return omit_one_operand (type, arg1, arg0); | |
4575 | if (integer_zerop (arg1)) | |
4576 | return non_lvalue (convert (type, arg0)); | |
4577 | t1 = distribute_bit_expr (code, type, arg0, arg1); | |
4578 | if (t1 != NULL_TREE) | |
4579 | return t1; | |
85d2e16c | 4580 | |
65d8b1ce | 4581 | /* (A << C1) | (A >> C2) if A is unsigned and C1+C2 is the size of A |
85d2e16c | 4582 | is a rotate of A by C1 bits. */ |
65d8b1ce RK |
4583 | /* (A << B) | (A >> (Z - B)) if A is unsigned and Z is the size of A |
4584 | is a rotate of A by B bits. */ | |
85d2e16c | 4585 | |
65d8b1ce RK |
4586 | code0 = TREE_CODE (arg0); |
4587 | code1 = TREE_CODE (arg1); | |
4588 | if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR) | |
4589 | || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR)) | |
85d2e16c | 4590 | && operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1,0), 0) |
65d8b1ce RK |
4591 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))) |
4592 | { | |
4593 | register tree tree01, tree11; | |
4594 | register enum tree_code code01, code11; | |
4595 | ||
4596 | tree01 = TREE_OPERAND (arg0, 1); | |
4597 | tree11 = TREE_OPERAND (arg1, 1); | |
4598 | code01 = TREE_CODE (tree01); | |
4599 | code11 = TREE_CODE (tree11); | |
4600 | if (code01 == INTEGER_CST | |
4601 | && code11 == INTEGER_CST | |
4602 | && TREE_INT_CST_HIGH (tree01) == 0 | |
4603 | && TREE_INT_CST_HIGH (tree11) == 0 | |
4604 | && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11)) | |
85d2e16c | 4605 | == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))))) |
65d8b1ce RK |
4606 | return build (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0), |
4607 | code0 == LSHIFT_EXPR ? tree01 : tree11); | |
4608 | else if (code11 == MINUS_EXPR | |
4609 | && TREE_CODE (TREE_OPERAND (tree11, 0)) == INTEGER_CST | |
4610 | && TREE_INT_CST_HIGH (TREE_OPERAND (tree11, 0)) == 0 | |
4611 | && TREE_INT_CST_LOW (TREE_OPERAND (tree11, 0)) | |
4612 | == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))) | |
4613 | && operand_equal_p (tree01, TREE_OPERAND (tree11, 1), 0)) | |
4614 | return build (code0 == LSHIFT_EXPR ? LROTATE_EXPR : RROTATE_EXPR, | |
4615 | type, TREE_OPERAND (arg0, 0), tree01); | |
4616 | else if (code01 == MINUS_EXPR | |
4617 | && TREE_CODE (TREE_OPERAND (tree01, 0)) == INTEGER_CST | |
4618 | && TREE_INT_CST_HIGH (TREE_OPERAND (tree01, 0)) == 0 | |
4619 | && TREE_INT_CST_LOW (TREE_OPERAND (tree01, 0)) | |
4620 | == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))) | |
4621 | && operand_equal_p (tree11, TREE_OPERAND (tree01, 1), 0)) | |
4622 | return build (code0 != LSHIFT_EXPR ? LROTATE_EXPR : RROTATE_EXPR, | |
4623 | type, TREE_OPERAND (arg0, 0), tree11); | |
4624 | } | |
85d2e16c | 4625 | |
6d716ca8 | 4626 | goto associate; |
65d8b1ce | 4627 | } |
6d716ca8 RS |
4628 | |
4629 | case BIT_XOR_EXPR: | |
4630 | if (integer_zerop (arg1)) | |
4631 | return non_lvalue (convert (type, arg0)); | |
4632 | if (integer_all_onesp (arg1)) | |
4633 | return fold (build1 (BIT_NOT_EXPR, type, arg0)); | |
4634 | goto associate; | |
4635 | ||
4636 | case BIT_AND_EXPR: | |
4637 | bit_and: | |
4638 | if (integer_all_onesp (arg1)) | |
4639 | return non_lvalue (convert (type, arg0)); | |
4640 | if (integer_zerop (arg1)) | |
4641 | return omit_one_operand (type, arg1, arg0); | |
4642 | t1 = distribute_bit_expr (code, type, arg0, arg1); | |
4643 | if (t1 != NULL_TREE) | |
4644 | return t1; | |
4645 | /* Simplify ((int)c & 0x377) into (int)c, if c is unsigned char. */ | |
4646 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == NOP_EXPR | |
4647 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg1, 0)))) | |
4648 | { | |
4649 | int prec = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg1, 0))); | |
906c4e36 RK |
4650 | if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT |
4651 | && (~TREE_INT_CST_LOW (arg0) | |
4652 | & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0) | |
6d716ca8 RS |
4653 | return build1 (NOP_EXPR, type, TREE_OPERAND (arg1, 0)); |
4654 | } | |
4655 | if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR | |
4656 | && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))) | |
4657 | { | |
4658 | int prec = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))); | |
906c4e36 RK |
4659 | if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT |
4660 | && (~TREE_INT_CST_LOW (arg1) | |
4661 | & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0) | |
6d716ca8 RS |
4662 | return build1 (NOP_EXPR, type, TREE_OPERAND (arg0, 0)); |
4663 | } | |
4664 | goto associate; | |
4665 | ||
4666 | case BIT_ANDTC_EXPR: | |
4667 | if (integer_all_onesp (arg0)) | |
4668 | return non_lvalue (convert (type, arg1)); | |
4669 | if (integer_zerop (arg0)) | |
4670 | return omit_one_operand (type, arg0, arg1); | |
4671 | if (TREE_CODE (arg1) == INTEGER_CST) | |
4672 | { | |
4673 | arg1 = fold (build1 (BIT_NOT_EXPR, type, arg1)); | |
4674 | code = BIT_AND_EXPR; | |
4675 | goto bit_and; | |
4676 | } | |
4677 | goto binary; | |
4678 | ||
e9aaa5a5 RK |
4679 | case RDIV_EXPR: |
4680 | /* In most cases, do nothing with a divide by zero. */ | |
4681 | #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC) | |
4682 | #ifndef REAL_INFINITY | |
4683 | if (TREE_CODE (arg1) == REAL_CST && real_zerop (arg1)) | |
4684 | return t; | |
4685 | #endif | |
4686 | #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */ | |
4687 | ||
4688 | /* In IEEE floating point, x/1 is not equivalent to x for snans. | |
4689 | However, ANSI says we can drop signals, so we can do this anyway. */ | |
4690 | if (real_onep (arg1)) | |
4691 | return non_lvalue (convert (type, arg0)); | |
4692 | ||
4693 | /* If ARG1 is a constant, we can convert this to a multiply by the | |
4694 | reciprocal. This does not have the same rounding properties, | |
4695 | so only do this if -ffast-math. We can actually always safely | |
4696 | do it if ARG1 is a power of two, but it's hard to tell if it is | |
4697 | or not in a portable manner. */ | |
39647dcb RK |
4698 | if (TREE_CODE (arg1) == REAL_CST) |
4699 | { | |
4700 | if (flag_fast_math | |
4701 | && 0 != (tem = const_binop (code, build_real (type, dconst1), | |
4702 | arg1, 0))) | |
4703 | return fold (build (MULT_EXPR, type, arg0, tem)); | |
4704 | /* Find the reciprocal if optimizing and the result is exact. */ | |
4705 | else if (optimize) | |
4706 | { | |
4707 | REAL_VALUE_TYPE r; | |
4708 | r = TREE_REAL_CST (arg1); | |
4709 | if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r)) | |
4710 | { | |
4711 | tem = build_real (type, r); | |
4712 | return fold (build (MULT_EXPR, type, arg0, tem)); | |
4713 | } | |
4714 | } | |
4715 | } | |
e9aaa5a5 RK |
4716 | goto binary; |
4717 | ||
6d716ca8 RS |
4718 | case TRUNC_DIV_EXPR: |
4719 | case ROUND_DIV_EXPR: | |
4720 | case FLOOR_DIV_EXPR: | |
4721 | case CEIL_DIV_EXPR: | |
4722 | case EXACT_DIV_EXPR: | |
6d716ca8 RS |
4723 | if (integer_onep (arg1)) |
4724 | return non_lvalue (convert (type, arg0)); | |
4725 | if (integer_zerop (arg1)) | |
4726 | return t; | |
3b998c11 | 4727 | |
39dfb55a JL |
4728 | /* If arg0 is a multiple of arg1, then rewrite to the fastest div |
4729 | operation, EXACT_DIV_EXPR. | |
4730 | ||
91585c63 TM |
4731 | Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now. |
4732 | At one time others generated faster code, it's not clear if they do | |
4733 | after the last round to changes to the DIV code in expmed.c. */ | |
4734 | if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR) | |
39dfb55a JL |
4735 | && multiple_of_p (type, arg0, arg1)) |
4736 | return fold (build (EXACT_DIV_EXPR, type, arg0, arg1)); | |
4737 | ||
37bdb7e3 | 4738 | /* If we have ((a / C1) / C2) where both division are the same type, try |
e9aaa5a5 RK |
4739 | to simplify. First see if C1 * C2 overflows or not. */ |
4740 | if (TREE_CODE (arg0) == code && TREE_CODE (arg1) == INTEGER_CST | |
4741 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
4742 | { | |
37bdb7e3 | 4743 | tree new_divisor; |
e9aaa5a5 | 4744 | |
37bdb7e3 TG |
4745 | new_divisor = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 1), arg1, 0); |
4746 | tem = const_binop (FLOOR_DIV_EXPR, new_divisor, arg1, 0); | |
3122945e | 4747 | |
37bdb7e3 TG |
4748 | if (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) == TREE_INT_CST_LOW (tem) |
4749 | && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == TREE_INT_CST_HIGH (tem)) | |
e9aaa5a5 | 4750 | { |
37bdb7e3 TG |
4751 | /* If no overflow, divide by C1*C2. */ |
4752 | return fold (build (code, type, TREE_OPERAND (arg0, 0), new_divisor)); | |
e9aaa5a5 | 4753 | } |
e9aaa5a5 RK |
4754 | } |
4755 | ||
6a96fcb4 RK |
4756 | /* Look for ((a * C1) / C3) or (((a * C1) + C2) / C3), |
4757 | where C1 % C3 == 0 or C3 % C1 == 0. We can simplify these | |
4758 | expressions, which often appear in the offsets or sizes of | |
4759 | objects with a varying size. Only deal with positive divisors | |
aae67841 | 4760 | and multiplicands. If C2 is negative, we must have C2 % C3 == 0. |
6a96fcb4 RK |
4761 | |
4762 | Look for NOPs and SAVE_EXPRs inside. */ | |
4763 | ||
3b998c11 | 4764 | if (TREE_CODE (arg1) == INTEGER_CST |
d0cb4c65 | 4765 | && tree_int_cst_sgn (arg1) >= 0) |
3b998c11 | 4766 | { |
6a96fcb4 RK |
4767 | int have_save_expr = 0; |
4768 | tree c2 = integer_zero_node; | |
4769 | tree xarg0 = arg0; | |
3b998c11 | 4770 | |
d011fbf9 | 4771 | if (TREE_CODE (xarg0) == SAVE_EXPR && SAVE_EXPR_RTL (xarg0) == 0) |
6a96fcb4 | 4772 | have_save_expr = 1, xarg0 = TREE_OPERAND (xarg0, 0); |
3b998c11 | 4773 | |
6a96fcb4 RK |
4774 | STRIP_NOPS (xarg0); |
4775 | ||
750e8348 TM |
4776 | /* Look inside the dividend and simplify using EXACT_DIV_EXPR |
4777 | if possible. */ | |
4778 | if (TREE_CODE (xarg0) == MULT_EXPR | |
4779 | && multiple_of_p (type, TREE_OPERAND (xarg0, 0), arg1)) | |
4780 | { | |
4781 | tree t; | |
4782 | ||
4783 | t = fold (build (MULT_EXPR, type, | |
4784 | fold (build (EXACT_DIV_EXPR, type, | |
4785 | TREE_OPERAND (xarg0, 0), arg1)), | |
4786 | TREE_OPERAND (xarg0, 1))); | |
4787 | if (have_save_expr) | |
4788 | t = save_expr (t); | |
4789 | return t; | |
4790 | ||
4791 | } | |
4792 | ||
4793 | if (TREE_CODE (xarg0) == MULT_EXPR | |
4794 | && multiple_of_p (type, TREE_OPERAND (xarg0, 1), arg1)) | |
4795 | { | |
4796 | tree t; | |
4797 | ||
4798 | t = fold (build (MULT_EXPR, type, | |
4799 | fold (build (EXACT_DIV_EXPR, type, | |
4800 | TREE_OPERAND (xarg0, 1), arg1)), | |
4801 | TREE_OPERAND (xarg0, 0))); | |
4802 | if (have_save_expr) | |
4803 | t = save_expr (t); | |
4804 | return t; | |
4805 | } | |
4806 | ||
6a96fcb4 RK |
4807 | if (TREE_CODE (xarg0) == PLUS_EXPR |
4808 | && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST) | |
4809 | c2 = TREE_OPERAND (xarg0, 1), xarg0 = TREE_OPERAND (xarg0, 0); | |
4810 | else if (TREE_CODE (xarg0) == MINUS_EXPR | |
aae67841 RK |
4811 | && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST |
4812 | /* If we are doing this computation unsigned, the negate | |
4813 | is incorrect. */ | |
4814 | && ! TREE_UNSIGNED (type)) | |
6a96fcb4 RK |
4815 | { |
4816 | c2 = fold (build1 (NEGATE_EXPR, type, TREE_OPERAND (xarg0, 1))); | |
4817 | xarg0 = TREE_OPERAND (xarg0, 0); | |
4818 | } | |
4819 | ||
d011fbf9 | 4820 | if (TREE_CODE (xarg0) == SAVE_EXPR && SAVE_EXPR_RTL (xarg0) == 0) |
6a96fcb4 RK |
4821 | have_save_expr = 1, xarg0 = TREE_OPERAND (xarg0, 0); |
4822 | ||
4823 | STRIP_NOPS (xarg0); | |
4824 | ||
4825 | if (TREE_CODE (xarg0) == MULT_EXPR | |
4826 | && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST | |
d0cb4c65 | 4827 | && tree_int_cst_sgn (TREE_OPERAND (xarg0, 1)) >= 0 |
6a96fcb4 RK |
4828 | && (integer_zerop (const_binop (TRUNC_MOD_EXPR, |
4829 | TREE_OPERAND (xarg0, 1), arg1, 1)) | |
4830 | || integer_zerop (const_binop (TRUNC_MOD_EXPR, arg1, | |
aae67841 | 4831 | TREE_OPERAND (xarg0, 1), 1))) |
d0cb4c65 | 4832 | && (tree_int_cst_sgn (c2) >= 0 |
aae67841 RK |
4833 | || integer_zerop (const_binop (TRUNC_MOD_EXPR, c2, |
4834 | arg1, 1)))) | |
6a96fcb4 RK |
4835 | { |
4836 | tree outer_div = integer_one_node; | |
4837 | tree c1 = TREE_OPERAND (xarg0, 1); | |
4838 | tree c3 = arg1; | |
4839 | ||
4840 | /* If C3 > C1, set them equal and do a divide by | |
4841 | C3/C1 at the end of the operation. */ | |
4842 | if (tree_int_cst_lt (c1, c3)) | |
4843 | outer_div = const_binop (code, c3, c1, 0), c3 = c1; | |
4844 | ||
4845 | /* The result is A * (C1/C3) + (C2/C3). */ | |
4846 | t = fold (build (PLUS_EXPR, type, | |
4847 | fold (build (MULT_EXPR, type, | |
4848 | TREE_OPERAND (xarg0, 0), | |
4849 | const_binop (code, c1, c3, 1))), | |
4850 | const_binop (code, c2, c3, 1))); | |
4851 | ||
4852 | if (! integer_onep (outer_div)) | |
d0cb4c65 | 4853 | t = fold (build (code, type, t, convert (type, outer_div))); |
6a96fcb4 RK |
4854 | |
4855 | if (have_save_expr) | |
4856 | t = save_expr (t); | |
4857 | ||
4858 | return t; | |
4859 | } | |
3b998c11 RK |
4860 | } |
4861 | ||
6d716ca8 RS |
4862 | goto binary; |
4863 | ||
4864 | case CEIL_MOD_EXPR: | |
4865 | case FLOOR_MOD_EXPR: | |
4866 | case ROUND_MOD_EXPR: | |
4867 | case TRUNC_MOD_EXPR: | |
4868 | if (integer_onep (arg1)) | |
4869 | return omit_one_operand (type, integer_zero_node, arg0); | |
4870 | if (integer_zerop (arg1)) | |
4871 | return t; | |
6a96fcb4 RK |
4872 | |
4873 | /* Look for ((a * C1) % C3) or (((a * C1) + C2) % C3), | |
4874 | where C1 % C3 == 0. Handle similarly to the division case, | |
4875 | but don't bother with SAVE_EXPRs. */ | |
4876 | ||
4877 | if (TREE_CODE (arg1) == INTEGER_CST | |
4878 | && ! integer_zerop (arg1)) | |
4879 | { | |
4880 | tree c2 = integer_zero_node; | |
4881 | tree xarg0 = arg0; | |
4882 | ||
4883 | if (TREE_CODE (xarg0) == PLUS_EXPR | |
4884 | && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST) | |
4885 | c2 = TREE_OPERAND (xarg0, 1), xarg0 = TREE_OPERAND (xarg0, 0); | |
4886 | else if (TREE_CODE (xarg0) == MINUS_EXPR | |
aae67841 RK |
4887 | && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST |
4888 | && ! TREE_UNSIGNED (type)) | |
6a96fcb4 RK |
4889 | { |
4890 | c2 = fold (build1 (NEGATE_EXPR, type, TREE_OPERAND (xarg0, 1))); | |
4891 | xarg0 = TREE_OPERAND (xarg0, 0); | |
4892 | } | |
4893 | ||
4894 | STRIP_NOPS (xarg0); | |
4895 | ||
4896 | if (TREE_CODE (xarg0) == MULT_EXPR | |
4897 | && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST | |
4898 | && integer_zerop (const_binop (TRUNC_MOD_EXPR, | |
4899 | TREE_OPERAND (xarg0, 1), | |
aae67841 | 4900 | arg1, 1)) |
d0cb4c65 | 4901 | && tree_int_cst_sgn (c2) >= 0) |
6a96fcb4 RK |
4902 | /* The result is (C2%C3). */ |
4903 | return omit_one_operand (type, const_binop (code, c2, arg1, 1), | |
4904 | TREE_OPERAND (xarg0, 0)); | |
4905 | } | |
4906 | ||
6d716ca8 RS |
4907 | goto binary; |
4908 | ||
4909 | case LSHIFT_EXPR: | |
4910 | case RSHIFT_EXPR: | |
4911 | case LROTATE_EXPR: | |
4912 | case RROTATE_EXPR: | |
4913 | if (integer_zerop (arg1)) | |
4914 | return non_lvalue (convert (type, arg0)); | |
4915 | /* Since negative shift count is not well-defined, | |
4916 | don't try to compute it in the compiler. */ | |
4d39710e | 4917 | if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0) |
6d716ca8 | 4918 | return t; |
4d39710e RK |
4919 | /* Rewrite an LROTATE_EXPR by a constant into an |
4920 | RROTATE_EXPR by a new constant. */ | |
4921 | if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST) | |
4922 | { | |
4923 | TREE_SET_CODE (t, RROTATE_EXPR); | |
4924 | code = RROTATE_EXPR; | |
4925 | TREE_OPERAND (t, 1) = arg1 | |
4926 | = const_binop | |
4927 | (MINUS_EXPR, | |
4928 | convert (TREE_TYPE (arg1), | |
4929 | build_int_2 (GET_MODE_BITSIZE (TYPE_MODE (type)), 0)), | |
4930 | arg1, 0); | |
4931 | if (tree_int_cst_sgn (arg1) < 0) | |
4932 | return t; | |
4933 | } | |
4934 | ||
4935 | /* If we have a rotate of a bit operation with the rotate count and | |
4936 | the second operand of the bit operation both constant, | |
4937 | permute the two operations. */ | |
4938 | if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
4939 | && (TREE_CODE (arg0) == BIT_AND_EXPR | |
4940 | || TREE_CODE (arg0) == BIT_ANDTC_EXPR | |
4941 | || TREE_CODE (arg0) == BIT_IOR_EXPR | |
4942 | || TREE_CODE (arg0) == BIT_XOR_EXPR) | |
4943 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) | |
4944 | return fold (build (TREE_CODE (arg0), type, | |
4945 | fold (build (code, type, | |
4946 | TREE_OPERAND (arg0, 0), arg1)), | |
4947 | fold (build (code, type, | |
4948 | TREE_OPERAND (arg0, 1), arg1)))); | |
4949 | ||
4950 | /* Two consecutive rotates adding up to the width of the mode can | |
4951 | be ignored. */ | |
4952 | if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST | |
4953 | && TREE_CODE (arg0) == RROTATE_EXPR | |
4954 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST | |
4955 | && TREE_INT_CST_HIGH (arg1) == 0 | |
4956 | && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0 | |
4957 | && ((TREE_INT_CST_LOW (arg1) | |
4958 | + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))) | |
4959 | == GET_MODE_BITSIZE (TYPE_MODE (type)))) | |
4960 | return TREE_OPERAND (arg0, 0); | |
4961 | ||
6d716ca8 RS |
4962 | goto binary; |
4963 | ||
4964 | case MIN_EXPR: | |
4965 | if (operand_equal_p (arg0, arg1, 0)) | |
4966 | return arg0; | |
7178e3af | 4967 | if (INTEGRAL_TYPE_P (type) |
6d716ca8 RS |
4968 | && operand_equal_p (arg1, TYPE_MIN_VALUE (type), 1)) |
4969 | return omit_one_operand (type, arg1, arg0); | |
4970 | goto associate; | |
4971 | ||
4972 | case MAX_EXPR: | |
4973 | if (operand_equal_p (arg0, arg1, 0)) | |
4974 | return arg0; | |
7178e3af | 4975 | if (INTEGRAL_TYPE_P (type) |
e1ee5cdc | 4976 | && TYPE_MAX_VALUE (type) |
6d716ca8 RS |
4977 | && operand_equal_p (arg1, TYPE_MAX_VALUE (type), 1)) |
4978 | return omit_one_operand (type, arg1, arg0); | |
4979 | goto associate; | |
4980 | ||
4981 | case TRUTH_NOT_EXPR: | |
4982 | /* Note that the operand of this must be an int | |
4983 | and its values must be 0 or 1. | |
4984 | ("true" is a fixed value perhaps depending on the language, | |
4985 | but we don't handle values other than 1 correctly yet.) */ | |
1180eb10 JM |
4986 | tem = invert_truthvalue (arg0); |
4987 | /* Avoid infinite recursion. */ | |
4988 | if (TREE_CODE (tem) == TRUTH_NOT_EXPR) | |
4989 | return t; | |
4990 | return convert (type, tem); | |
6d716ca8 RS |
4991 | |
4992 | case TRUTH_ANDIF_EXPR: | |
4993 | /* Note that the operands of this must be ints | |
4994 | and their values must be 0 or 1. | |
4995 | ("true" is a fixed value perhaps depending on the language.) */ | |
4996 | /* If first arg is constant zero, return it. */ | |
772447c5 | 4997 | if (integer_zerop (arg0)) |
6d716ca8 RS |
4998 | return arg0; |
4999 | case TRUTH_AND_EXPR: | |
5000 | /* If either arg is constant true, drop it. */ | |
5001 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
5002 | return non_lvalue (arg1); | |
5003 | if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)) | |
5004 | return non_lvalue (arg0); | |
772447c5 RK |
5005 | /* If second arg is constant zero, result is zero, but first arg |
5006 | must be evaluated. */ | |
5007 | if (integer_zerop (arg1)) | |
5008 | return omit_one_operand (type, arg1, arg0); | |
80906567 RK |
5009 | /* Likewise for first arg, but note that only the TRUTH_AND_EXPR |
5010 | case will be handled here. */ | |
5011 | if (integer_zerop (arg0)) | |
5012 | return omit_one_operand (type, arg0, arg1); | |
6d716ca8 RS |
5013 | |
5014 | truth_andor: | |
e9b5e15f RK |
5015 | /* We only do these simplifications if we are optimizing. */ |
5016 | if (!optimize) | |
5017 | return t; | |
5018 | ||
5019 | /* Check for things like (A || B) && (A || C). We can convert this | |
5020 | to A || (B && C). Note that either operator can be any of the four | |
5021 | truth and/or operations and the transformation will still be | |
5022 | valid. Also note that we only care about order for the | |
96f06cb6 RK |
5023 | ANDIF and ORIF operators. If B contains side effects, this |
5024 | might change the truth-value of A. */ | |
e9b5e15f RK |
5025 | if (TREE_CODE (arg0) == TREE_CODE (arg1) |
5026 | && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR | |
5027 | || TREE_CODE (arg0) == TRUTH_ORIF_EXPR | |
5028 | || TREE_CODE (arg0) == TRUTH_AND_EXPR | |
96f06cb6 RK |
5029 | || TREE_CODE (arg0) == TRUTH_OR_EXPR) |
5030 | && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1))) | |
e9b5e15f RK |
5031 | { |
5032 | tree a00 = TREE_OPERAND (arg0, 0); | |
5033 | tree a01 = TREE_OPERAND (arg0, 1); | |
5034 | tree a10 = TREE_OPERAND (arg1, 0); | |
5035 | tree a11 = TREE_OPERAND (arg1, 1); | |
5036 | int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR | |
5037 | || TREE_CODE (arg0) == TRUTH_AND_EXPR) | |
5038 | && (code == TRUTH_AND_EXPR | |
5039 | || code == TRUTH_OR_EXPR)); | |
5040 | ||
5041 | if (operand_equal_p (a00, a10, 0)) | |
5042 | return fold (build (TREE_CODE (arg0), type, a00, | |
5043 | fold (build (code, type, a01, a11)))); | |
5044 | else if (commutative && operand_equal_p (a00, a11, 0)) | |
5045 | return fold (build (TREE_CODE (arg0), type, a00, | |
5046 | fold (build (code, type, a01, a10)))); | |
5047 | else if (commutative && operand_equal_p (a01, a10, 0)) | |
5048 | return fold (build (TREE_CODE (arg0), type, a01, | |
5049 | fold (build (code, type, a00, a11)))); | |
5050 | ||
5051 | /* This case if tricky because we must either have commutative | |
5052 | operators or else A10 must not have side-effects. */ | |
5053 | ||
5054 | else if ((commutative || ! TREE_SIDE_EFFECTS (a10)) | |
5055 | && operand_equal_p (a01, a11, 0)) | |
5056 | return fold (build (TREE_CODE (arg0), type, | |
5057 | fold (build (code, type, a00, a10)), | |
5058 | a01)); | |
5059 | } | |
5060 | ||
ebde8a27 RK |
5061 | /* See if we can build a range comparison. */ |
5062 | if (0 != (tem = fold_range_test (t))) | |
5063 | return tem; | |
5064 | ||
6d716ca8 RS |
5065 | /* Check for the possibility of merging component references. If our |
5066 | lhs is another similar operation, try to merge its rhs with our | |
5067 | rhs. Then try to merge our lhs and rhs. */ | |
e9b5e15f RK |
5068 | if (TREE_CODE (arg0) == code |
5069 | && 0 != (tem = fold_truthop (code, type, | |
5070 | TREE_OPERAND (arg0, 1), arg1))) | |
5071 | return fold (build (code, type, TREE_OPERAND (arg0, 0), tem)); | |
6d716ca8 | 5072 | |
e9b5e15f RK |
5073 | if ((tem = fold_truthop (code, type, arg0, arg1)) != 0) |
5074 | return tem; | |
61f275ff | 5075 | |
6d716ca8 RS |
5076 | return t; |
5077 | ||
5078 | case TRUTH_ORIF_EXPR: | |
5079 | /* Note that the operands of this must be ints | |
5080 | and their values must be 0 or true. | |
5081 | ("true" is a fixed value perhaps depending on the language.) */ | |
5082 | /* If first arg is constant true, return it. */ | |
5083 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
5084 | return arg0; | |
5085 | case TRUTH_OR_EXPR: | |
5086 | /* If either arg is constant zero, drop it. */ | |
5087 | if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0)) | |
5088 | return non_lvalue (arg1); | |
5089 | if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1)) | |
5090 | return non_lvalue (arg0); | |
772447c5 RK |
5091 | /* If second arg is constant true, result is true, but we must |
5092 | evaluate first arg. */ | |
5093 | if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)) | |
5094 | return omit_one_operand (type, arg1, arg0); | |
80906567 RK |
5095 | /* Likewise for first arg, but note this only occurs here for |
5096 | TRUTH_OR_EXPR. */ | |
5097 | if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0)) | |
5098 | return omit_one_operand (type, arg0, arg1); | |
6d716ca8 RS |
5099 | goto truth_andor; |
5100 | ||
772447c5 RK |
5101 | case TRUTH_XOR_EXPR: |
5102 | /* If either arg is constant zero, drop it. */ | |
5103 | if (integer_zerop (arg0)) | |
5104 | return non_lvalue (arg1); | |
5105 | if (integer_zerop (arg1)) | |
5106 | return non_lvalue (arg0); | |
5107 | /* If either arg is constant true, this is a logical inversion. */ | |
5108 | if (integer_onep (arg0)) | |
5109 | return non_lvalue (invert_truthvalue (arg1)); | |
5110 | if (integer_onep (arg1)) | |
5111 | return non_lvalue (invert_truthvalue (arg0)); | |
62d8b51e | 5112 | return t; |
772447c5 | 5113 | |
6d716ca8 RS |
5114 | case EQ_EXPR: |
5115 | case NE_EXPR: | |
5116 | case LT_EXPR: | |
5117 | case GT_EXPR: | |
5118 | case LE_EXPR: | |
5119 | case GE_EXPR: | |
5120 | /* If one arg is a constant integer, put it last. */ | |
5121 | if (TREE_CODE (arg0) == INTEGER_CST | |
5122 | && TREE_CODE (arg1) != INTEGER_CST) | |
5123 | { | |
5124 | TREE_OPERAND (t, 0) = arg1; | |
5125 | TREE_OPERAND (t, 1) = arg0; | |
5126 | arg0 = TREE_OPERAND (t, 0); | |
5127 | arg1 = TREE_OPERAND (t, 1); | |
c05a9b68 | 5128 | code = swap_tree_comparison (code); |
6d716ca8 RS |
5129 | TREE_SET_CODE (t, code); |
5130 | } | |
5131 | ||
5132 | /* Convert foo++ == CONST into ++foo == CONST + INCR. | |
5133 | First, see if one arg is constant; find the constant arg | |
5134 | and the other one. */ | |
5135 | { | |
4e86caed | 5136 | tree constop = 0, varop = NULL_TREE; |
cd7ece66 | 5137 | int constopnum = -1; |
6d716ca8 RS |
5138 | |
5139 | if (TREE_CONSTANT (arg1)) | |
cd7ece66 | 5140 | constopnum = 1, constop = arg1, varop = arg0; |
6d716ca8 | 5141 | if (TREE_CONSTANT (arg0)) |
cd7ece66 | 5142 | constopnum = 0, constop = arg0, varop = arg1; |
6d716ca8 RS |
5143 | |
5144 | if (constop && TREE_CODE (varop) == POSTINCREMENT_EXPR) | |
5145 | { | |
6d716ca8 RS |
5146 | /* This optimization is invalid for ordered comparisons |
5147 | if CONST+INCR overflows or if foo+incr might overflow. | |
c05a9b68 | 5148 | This optimization is invalid for floating point due to rounding. |
6d716ca8 | 5149 | For pointer types we assume overflow doesn't happen. */ |
e5e809f4 | 5150 | if (POINTER_TYPE_P (TREE_TYPE (varop)) |
7178e3af | 5151 | || (! FLOAT_TYPE_P (TREE_TYPE (varop)) |
c05a9b68 | 5152 | && (code == EQ_EXPR || code == NE_EXPR))) |
6d716ca8 | 5153 | { |
c05a9b68 RS |
5154 | tree newconst |
5155 | = fold (build (PLUS_EXPR, TREE_TYPE (varop), | |
5156 | constop, TREE_OPERAND (varop, 1))); | |
5157 | TREE_SET_CODE (varop, PREINCREMENT_EXPR); | |
cd7ece66 | 5158 | |
30eca391 RK |
5159 | /* If VAROP is a reference to a bitfield, we must mask |
5160 | the constant by the width of the field. */ | |
5161 | if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF | |
5162 | && DECL_BIT_FIELD(TREE_OPERAND | |
5163 | (TREE_OPERAND (varop, 0), 1))) | |
5164 | { | |
5165 | int size | |
5166 | = TREE_INT_CST_LOW (DECL_SIZE | |
5167 | (TREE_OPERAND | |
5168 | (TREE_OPERAND (varop, 0), 1))); | |
5169 | ||
5170 | newconst = fold (build (BIT_AND_EXPR, | |
5171 | TREE_TYPE (varop), newconst, | |
5172 | convert (TREE_TYPE (varop), | |
5173 | build_int_2 (size, 0)))); | |
5174 | } | |
5175 | ||
5176 | ||
cd7ece66 RK |
5177 | t = build (code, type, TREE_OPERAND (t, 0), |
5178 | TREE_OPERAND (t, 1)); | |
5179 | TREE_OPERAND (t, constopnum) = newconst; | |
c05a9b68 | 5180 | return t; |
6d716ca8 RS |
5181 | } |
5182 | } | |
5183 | else if (constop && TREE_CODE (varop) == POSTDECREMENT_EXPR) | |
5184 | { | |
e5e809f4 | 5185 | if (POINTER_TYPE_P (TREE_TYPE (varop)) |
7178e3af | 5186 | || (! FLOAT_TYPE_P (TREE_TYPE (varop)) |
c05a9b68 | 5187 | && (code == EQ_EXPR || code == NE_EXPR))) |
6d716ca8 | 5188 | { |
c05a9b68 RS |
5189 | tree newconst |
5190 | = fold (build (MINUS_EXPR, TREE_TYPE (varop), | |
5191 | constop, TREE_OPERAND (varop, 1))); | |
5192 | TREE_SET_CODE (varop, PREDECREMENT_EXPR); | |
30eca391 RK |
5193 | |
5194 | if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF | |
5195 | && DECL_BIT_FIELD(TREE_OPERAND | |
5196 | (TREE_OPERAND (varop, 0), 1))) | |
5197 | { | |
5198 | int size | |
5199 | = TREE_INT_CST_LOW (DECL_SIZE | |
5200 | (TREE_OPERAND | |
5201 | (TREE_OPERAND (varop, 0), 1))); | |
5202 | ||
5203 | newconst = fold (build (BIT_AND_EXPR, | |
5204 | TREE_TYPE (varop), newconst, | |
5205 | convert (TREE_TYPE (varop), | |
5206 | build_int_2 (size, 0)))); | |
5207 | } | |
5208 | ||
5209 | ||
cd7ece66 RK |
5210 | t = build (code, type, TREE_OPERAND (t, 0), |
5211 | TREE_OPERAND (t, 1)); | |
5212 | TREE_OPERAND (t, constopnum) = newconst; | |
c05a9b68 | 5213 | return t; |
6d716ca8 RS |
5214 | } |
5215 | } | |
5216 | } | |
5217 | ||
5218 | /* Change X >= CST to X > (CST - 1) if CST is positive. */ | |
5219 | if (TREE_CODE (arg1) == INTEGER_CST | |
5220 | && TREE_CODE (arg0) != INTEGER_CST | |
d0cb4c65 | 5221 | && tree_int_cst_sgn (arg1) > 0) |
6d716ca8 RS |
5222 | { |
5223 | switch (TREE_CODE (t)) | |
5224 | { | |
5225 | case GE_EXPR: | |
5226 | code = GT_EXPR; | |
91d33e36 | 5227 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
cd7ece66 | 5228 | t = build (code, type, TREE_OPERAND (t, 0), arg1); |
6d716ca8 RS |
5229 | break; |
5230 | ||
5231 | case LT_EXPR: | |
5232 | code = LE_EXPR; | |
91d33e36 | 5233 | arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0); |
cd7ece66 RK |
5234 | t = build (code, type, TREE_OPERAND (t, 0), arg1); |
5235 | break; | |
e9a25f70 JL |
5236 | |
5237 | default: | |
5238 | break; | |
6d716ca8 RS |
5239 | } |
5240 | } | |
5241 | ||
6d716ca8 RS |
5242 | /* If this is an EQ or NE comparison with zero and ARG0 is |
5243 | (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require | |
5244 | two operations, but the latter can be done in one less insn | |
e9a25f70 | 5245 | on machines that have only two-operand insns or on which a |
6d716ca8 RS |
5246 | constant cannot be the first operand. */ |
5247 | if (integer_zerop (arg1) && (code == EQ_EXPR || code == NE_EXPR) | |
5248 | && TREE_CODE (arg0) == BIT_AND_EXPR) | |
5249 | { | |
5250 | if (TREE_CODE (TREE_OPERAND (arg0, 0)) == LSHIFT_EXPR | |
5251 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 0), 0))) | |
5252 | return | |
5253 | fold (build (code, type, | |
5254 | build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
5255 | build (RSHIFT_EXPR, | |
5256 | TREE_TYPE (TREE_OPERAND (arg0, 0)), | |
5257 | TREE_OPERAND (arg0, 1), | |
5258 | TREE_OPERAND (TREE_OPERAND (arg0, 0), 1)), | |
5259 | convert (TREE_TYPE (arg0), | |
5260 | integer_one_node)), | |
5261 | arg1)); | |
5262 | else if (TREE_CODE (TREE_OPERAND (arg0, 1)) == LSHIFT_EXPR | |
5263 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 1), 0))) | |
5264 | return | |
5265 | fold (build (code, type, | |
5266 | build (BIT_AND_EXPR, TREE_TYPE (arg0), | |
5267 | build (RSHIFT_EXPR, | |
5268 | TREE_TYPE (TREE_OPERAND (arg0, 1)), | |
5269 | TREE_OPERAND (arg0, 0), | |
5270 | TREE_OPERAND (TREE_OPERAND (arg0, 1), 1)), | |
5271 | convert (TREE_TYPE (arg0), | |
5272 | integer_one_node)), | |
5273 | arg1)); | |
5274 | } | |
5275 | ||
05a0d5ea | 5276 | /* If this is an NE or EQ comparison of zero against the result of a |
79bf94d3 RK |
5277 | signed MOD operation whose second operand is a power of 2, make |
5278 | the MOD operation unsigned since it is simpler and equivalent. */ | |
05a0d5ea RK |
5279 | if ((code == NE_EXPR || code == EQ_EXPR) |
5280 | && integer_zerop (arg1) | |
5281 | && ! TREE_UNSIGNED (TREE_TYPE (arg0)) | |
5282 | && (TREE_CODE (arg0) == TRUNC_MOD_EXPR | |
5283 | || TREE_CODE (arg0) == CEIL_MOD_EXPR | |
5284 | || TREE_CODE (arg0) == FLOOR_MOD_EXPR | |
79bf94d3 RK |
5285 | || TREE_CODE (arg0) == ROUND_MOD_EXPR) |
5286 | && integer_pow2p (TREE_OPERAND (arg0, 1))) | |
05a0d5ea RK |
5287 | { |
5288 | tree newtype = unsigned_type (TREE_TYPE (arg0)); | |
5289 | tree newmod = build (TREE_CODE (arg0), newtype, | |
5290 | convert (newtype, TREE_OPERAND (arg0, 0)), | |
5291 | convert (newtype, TREE_OPERAND (arg0, 1))); | |
5292 | ||
5293 | return build (code, type, newmod, convert (newtype, arg1)); | |
5294 | } | |
5295 | ||
6d716ca8 RS |
5296 | /* If this is an NE comparison of zero with an AND of one, remove the |
5297 | comparison since the AND will give the correct value. */ | |
5298 | if (code == NE_EXPR && integer_zerop (arg1) | |
5299 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
5300 | && integer_onep (TREE_OPERAND (arg0, 1))) | |
5301 | return convert (type, arg0); | |
5302 | ||
5303 | /* If we have (A & C) == C where C is a power of 2, convert this into | |
5304 | (A & C) != 0. Similarly for NE_EXPR. */ | |
5305 | if ((code == EQ_EXPR || code == NE_EXPR) | |
5306 | && TREE_CODE (arg0) == BIT_AND_EXPR | |
5307 | && integer_pow2p (TREE_OPERAND (arg0, 1)) | |
5308 | && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)) | |
5309 | return build (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type, | |
5310 | arg0, integer_zero_node); | |
5311 | ||
e92d3048 | 5312 | /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0 |
34b1b41f | 5313 | and similarly for >= into !=. */ |
e92d3048 RK |
5314 | if ((code == LT_EXPR || code == GE_EXPR) |
5315 | && TREE_UNSIGNED (TREE_TYPE (arg0)) | |
5316 | && TREE_CODE (arg1) == LSHIFT_EXPR | |
5317 | && integer_onep (TREE_OPERAND (arg1, 0))) | |
5318 | return build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type, | |
5319 | build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0, | |
5320 | TREE_OPERAND (arg1, 1)), | |
5321 | convert (TREE_TYPE (arg0), integer_zero_node)); | |
5322 | ||
5323 | else if ((code == LT_EXPR || code == GE_EXPR) | |
5324 | && TREE_UNSIGNED (TREE_TYPE (arg0)) | |
5325 | && (TREE_CODE (arg1) == NOP_EXPR | |
5326 | || TREE_CODE (arg1) == CONVERT_EXPR) | |
5327 | && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR | |
5328 | && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0))) | |
5329 | return | |
5330 | build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type, | |
5331 | convert (TREE_TYPE (arg0), | |
5332 | build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0, | |
5333 | TREE_OPERAND (TREE_OPERAND (arg1, 0), 1))), | |
5334 | convert (TREE_TYPE (arg0), integer_zero_node)); | |
5335 | ||
c05a9b68 RS |
5336 | /* Simplify comparison of something with itself. (For IEEE |
5337 | floating-point, we can only do some of these simplifications.) */ | |
5338 | if (operand_equal_p (arg0, arg1, 0)) | |
6d716ca8 RS |
5339 | { |
5340 | switch (code) | |
5341 | { | |
5342 | case EQ_EXPR: | |
5343 | case GE_EXPR: | |
5344 | case LE_EXPR: | |
7178e3af | 5345 | if (INTEGRAL_TYPE_P (TREE_TYPE (arg0))) |
c05a9b68 | 5346 | { |
380ff34a RK |
5347 | if (type == integer_type_node) |
5348 | return integer_one_node; | |
5349 | ||
c05a9b68 RS |
5350 | t = build_int_2 (1, 0); |
5351 | TREE_TYPE (t) = type; | |
5352 | return t; | |
5353 | } | |
5354 | code = EQ_EXPR; | |
5355 | TREE_SET_CODE (t, code); | |
5356 | break; | |
5357 | ||
6d716ca8 | 5358 | case NE_EXPR: |
c05a9b68 | 5359 | /* For NE, we can only do this simplification if integer. */ |
7178e3af | 5360 | if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0))) |
c05a9b68 | 5361 | break; |
0f41302f | 5362 | /* ... fall through ... */ |
6d716ca8 RS |
5363 | case GT_EXPR: |
5364 | case LT_EXPR: | |
380ff34a RK |
5365 | if (type == integer_type_node) |
5366 | return integer_zero_node; | |
5367 | ||
6d716ca8 RS |
5368 | t = build_int_2 (0, 0); |
5369 | TREE_TYPE (t) = type; | |
5370 | return t; | |
e9a25f70 JL |
5371 | default: |
5372 | abort (); | |
6d716ca8 RS |
5373 | } |
5374 | } | |
5375 | ||
5376 | /* An unsigned comparison against 0 can be simplified. */ | |
5377 | if (integer_zerop (arg1) | |
7178e3af | 5378 | && (INTEGRAL_TYPE_P (TREE_TYPE (arg1)) |
e5e809f4 | 5379 | || POINTER_TYPE_P (TREE_TYPE (arg1))) |
6d716ca8 RS |
5380 | && TREE_UNSIGNED (TREE_TYPE (arg1))) |
5381 | { | |
5382 | switch (TREE_CODE (t)) | |
5383 | { | |
5384 | case GT_EXPR: | |
c05a9b68 | 5385 | code = NE_EXPR; |
6d716ca8 RS |
5386 | TREE_SET_CODE (t, NE_EXPR); |
5387 | break; | |
5388 | case LE_EXPR: | |
c05a9b68 | 5389 | code = EQ_EXPR; |
6d716ca8 RS |
5390 | TREE_SET_CODE (t, EQ_EXPR); |
5391 | break; | |
5392 | case GE_EXPR: | |
56f8e5e6 RK |
5393 | return omit_one_operand (type, |
5394 | convert (type, integer_one_node), | |
5395 | arg0); | |
6d716ca8 | 5396 | case LT_EXPR: |
56f8e5e6 RK |
5397 | return omit_one_operand (type, |
5398 | convert (type, integer_zero_node), | |
5399 | arg0); | |
e9a25f70 JL |
5400 | default: |
5401 | break; | |
6d716ca8 RS |
5402 | } |
5403 | } | |
5404 | ||
e9a25f70 JL |
5405 | /* An unsigned <= 0x7fffffff can be simplified. */ |
5406 | { | |
5407 | int width = TYPE_PRECISION (TREE_TYPE (arg1)); | |
5408 | if (TREE_CODE (arg1) == INTEGER_CST | |
5409 | && ! TREE_CONSTANT_OVERFLOW (arg1) | |
5410 | && width <= HOST_BITS_PER_WIDE_INT | |
5411 | && TREE_INT_CST_LOW (arg1) == ((HOST_WIDE_INT) 1 << (width - 1)) - 1 | |
5412 | && TREE_INT_CST_HIGH (arg1) == 0 | |
5413 | && (INTEGRAL_TYPE_P (TREE_TYPE (arg1)) | |
e5e809f4 | 5414 | || POINTER_TYPE_P (TREE_TYPE (arg1))) |
e9a25f70 JL |
5415 | && TREE_UNSIGNED (TREE_TYPE (arg1))) |
5416 | { | |
5417 | switch (TREE_CODE (t)) | |
5418 | { | |
5419 | case LE_EXPR: | |
5420 | return fold (build (GE_EXPR, type, | |
5421 | convert (signed_type (TREE_TYPE (arg0)), | |
5422 | arg0), | |
5423 | convert (signed_type (TREE_TYPE (arg1)), | |
5424 | integer_zero_node))); | |
5425 | case GT_EXPR: | |
5426 | return fold (build (LT_EXPR, type, | |
5427 | convert (signed_type (TREE_TYPE (arg0)), | |
5428 | arg0), | |
5429 | convert (signed_type (TREE_TYPE (arg1)), | |
5430 | integer_zero_node))); | |
1d300e19 KG |
5431 | default: |
5432 | break; | |
e9a25f70 JL |
5433 | } |
5434 | } | |
5435 | } | |
5436 | ||
c05a9b68 RS |
5437 | /* If we are comparing an expression that just has comparisons |
5438 | of two integer values, arithmetic expressions of those comparisons, | |
5439 | and constants, we can simplify it. There are only three cases | |
5440 | to check: the two values can either be equal, the first can be | |
5441 | greater, or the second can be greater. Fold the expression for | |
5442 | those three values. Since each value must be 0 or 1, we have | |
5443 | eight possibilities, each of which corresponds to the constant 0 | |
5444 | or 1 or one of the six possible comparisons. | |
5445 | ||
5446 | This handles common cases like (a > b) == 0 but also handles | |
5447 | expressions like ((x > y) - (y > x)) > 0, which supposedly | |
5448 | occur in macroized code. */ | |
5449 | ||
5450 | if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST) | |
5451 | { | |
5452 | tree cval1 = 0, cval2 = 0; | |
35e66bd1 | 5453 | int save_p = 0; |
c05a9b68 | 5454 | |
35e66bd1 | 5455 | if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p) |
c05a9b68 RS |
5456 | /* Don't handle degenerate cases here; they should already |
5457 | have been handled anyway. */ | |
5458 | && cval1 != 0 && cval2 != 0 | |
5459 | && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2)) | |
5460 | && TREE_TYPE (cval1) == TREE_TYPE (cval2) | |
7178e3af | 5461 | && INTEGRAL_TYPE_P (TREE_TYPE (cval1)) |
e1ee5cdc RH |
5462 | && TYPE_MAX_VALUE (TREE_TYPE (cval1)) |
5463 | && TYPE_MAX_VALUE (TREE_TYPE (cval2)) | |
c05a9b68 RS |
5464 | && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)), |
5465 | TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0)) | |
5466 | { | |
5467 | tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1)); | |
5468 | tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1)); | |
5469 | ||
5470 | /* We can't just pass T to eval_subst in case cval1 or cval2 | |
5471 | was the same as ARG1. */ | |
5472 | ||
5473 | tree high_result | |
5474 | = fold (build (code, type, | |
5475 | eval_subst (arg0, cval1, maxval, cval2, minval), | |
5476 | arg1)); | |
5477 | tree equal_result | |
5478 | = fold (build (code, type, | |
5479 | eval_subst (arg0, cval1, maxval, cval2, maxval), | |
5480 | arg1)); | |
5481 | tree low_result | |
5482 | = fold (build (code, type, | |
5483 | eval_subst (arg0, cval1, minval, cval2, maxval), | |
5484 | arg1)); | |
5485 | ||
5486 | /* All three of these results should be 0 or 1. Confirm they | |
5487 | are. Then use those values to select the proper code | |
5488 | to use. */ | |
5489 | ||
5490 | if ((integer_zerop (high_result) | |
5491 | || integer_onep (high_result)) | |
5492 | && (integer_zerop (equal_result) | |
5493 | || integer_onep (equal_result)) | |
5494 | && (integer_zerop (low_result) | |
5495 | || integer_onep (low_result))) | |
5496 | { | |
5497 | /* Make a 3-bit mask with the high-order bit being the | |
5498 | value for `>', the next for '=', and the low for '<'. */ | |
5499 | switch ((integer_onep (high_result) * 4) | |
5500 | + (integer_onep (equal_result) * 2) | |
5501 | + integer_onep (low_result)) | |
5502 | { | |
5503 | case 0: | |
5504 | /* Always false. */ | |
13837058 | 5505 | return omit_one_operand (type, integer_zero_node, arg0); |
c05a9b68 RS |
5506 | case 1: |
5507 | code = LT_EXPR; | |
5508 | break; | |
5509 | case 2: | |
5510 | code = EQ_EXPR; | |
5511 | break; | |
5512 | case 3: | |
5513 | code = LE_EXPR; | |
5514 | break; | |
5515 | case 4: | |
5516 | code = GT_EXPR; | |
5517 | break; | |
5518 | case 5: | |
5519 | code = NE_EXPR; | |
5520 | break; | |
5521 | case 6: | |
5522 | code = GE_EXPR; | |
5523 | break; | |
5524 | case 7: | |
5525 | /* Always true. */ | |
13837058 | 5526 | return omit_one_operand (type, integer_one_node, arg0); |
c05a9b68 RS |
5527 | } |
5528 | ||
35e66bd1 RK |
5529 | t = build (code, type, cval1, cval2); |
5530 | if (save_p) | |
5531 | return save_expr (t); | |
5532 | else | |
5533 | return fold (t); | |
c05a9b68 RS |
5534 | } |
5535 | } | |
5536 | } | |
5537 | ||
5538 | /* If this is a comparison of a field, we may be able to simplify it. */ | |
5539 | if ((TREE_CODE (arg0) == COMPONENT_REF | |
ebde8a27 RK |
5540 | || TREE_CODE (arg0) == BIT_FIELD_REF) |
5541 | && (code == EQ_EXPR || code == NE_EXPR) | |
5542 | /* Handle the constant case even without -O | |
5543 | to make sure the warnings are given. */ | |
5544 | && (optimize || TREE_CODE (arg1) == INTEGER_CST)) | |
c05a9b68 RS |
5545 | { |
5546 | t1 = optimize_bit_field_compare (code, type, arg0, arg1); | |
5547 | return t1 ? t1 : t; | |
5548 | } | |
5549 | ||
95aa28ae RK |
5550 | /* If this is a comparison of complex values and either or both |
5551 | sizes are a COMPLEX_EXPR, it is best to split up the comparisons | |
5552 | and join them with a TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR. This | |
5553 | may prevent needless evaluations. */ | |
5554 | if ((code == EQ_EXPR || code == NE_EXPR) | |
5555 | && TREE_CODE (TREE_TYPE (arg0)) == COMPLEX_TYPE | |
5556 | && (TREE_CODE (arg0) == COMPLEX_EXPR | |
5557 | || TREE_CODE (arg1) == COMPLEX_EXPR)) | |
5558 | { | |
5559 | tree subtype = TREE_TYPE (TREE_TYPE (arg0)); | |
5560 | tree real0 = fold (build1 (REALPART_EXPR, subtype, arg0)); | |
5561 | tree imag0 = fold (build1 (IMAGPART_EXPR, subtype, arg0)); | |
5562 | tree real1 = fold (build1 (REALPART_EXPR, subtype, arg1)); | |
5563 | tree imag1 = fold (build1 (IMAGPART_EXPR, subtype, arg1)); | |
5564 | ||
5565 | return fold (build ((code == EQ_EXPR ? TRUTH_ANDIF_EXPR | |
5566 | : TRUTH_ORIF_EXPR), | |
5567 | type, | |
5568 | fold (build (code, type, real0, real1)), | |
5569 | fold (build (code, type, imag0, imag1)))); | |
5570 | } | |
5571 | ||
c05a9b68 RS |
5572 | /* From here on, the only cases we handle are when the result is |
5573 | known to be a constant. | |
5574 | ||
5575 | To compute GT, swap the arguments and do LT. | |
6d716ca8 RS |
5576 | To compute GE, do LT and invert the result. |
5577 | To compute LE, swap the arguments, do LT and invert the result. | |
c05a9b68 RS |
5578 | To compute NE, do EQ and invert the result. |
5579 | ||
5580 | Therefore, the code below must handle only EQ and LT. */ | |
5581 | ||
6d716ca8 RS |
5582 | if (code == LE_EXPR || code == GT_EXPR) |
5583 | { | |
c05a9b68 RS |
5584 | tem = arg0, arg0 = arg1, arg1 = tem; |
5585 | code = swap_tree_comparison (code); | |
5586 | } | |
5587 | ||
5588 | /* Note that it is safe to invert for real values here because we | |
5589 | will check below in the one case that it matters. */ | |
5590 | ||
5591 | invert = 0; | |
5592 | if (code == NE_EXPR || code == GE_EXPR) | |
5593 | { | |
5594 | invert = 1; | |
5595 | code = invert_tree_comparison (code); | |
6d716ca8 RS |
5596 | } |
5597 | ||
5598 | /* Compute a result for LT or EQ if args permit; | |
5599 | otherwise return T. */ | |
c05a9b68 | 5600 | if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST) |
6d716ca8 | 5601 | { |
c05a9b68 RS |
5602 | if (code == EQ_EXPR) |
5603 | t1 = build_int_2 ((TREE_INT_CST_LOW (arg0) | |
5604 | == TREE_INT_CST_LOW (arg1)) | |
5605 | && (TREE_INT_CST_HIGH (arg0) | |
5606 | == TREE_INT_CST_HIGH (arg1)), | |
5607 | 0); | |
6d716ca8 | 5608 | else |
c05a9b68 RS |
5609 | t1 = build_int_2 ((TREE_UNSIGNED (TREE_TYPE (arg0)) |
5610 | ? INT_CST_LT_UNSIGNED (arg0, arg1) | |
5611 | : INT_CST_LT (arg0, arg1)), | |
5612 | 0); | |
6d716ca8 | 5613 | } |
c05a9b68 | 5614 | |
e80c9ccb | 5615 | #if 0 /* This is no longer useful, but breaks some real code. */ |
6d716ca8 RS |
5616 | /* Assume a nonexplicit constant cannot equal an explicit one, |
5617 | since such code would be undefined anyway. | |
5618 | Exception: on sysvr4, using #pragma weak, | |
5619 | a label can come out as 0. */ | |
5620 | else if (TREE_CODE (arg1) == INTEGER_CST | |
5621 | && !integer_zerop (arg1) | |
5622 | && TREE_CONSTANT (arg0) | |
5623 | && TREE_CODE (arg0) == ADDR_EXPR | |
c05a9b68 RS |
5624 | && code == EQ_EXPR) |
5625 | t1 = build_int_2 (0, 0); | |
e80c9ccb | 5626 | #endif |
6d716ca8 | 5627 | /* Two real constants can be compared explicitly. */ |
c05a9b68 | 5628 | else if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST) |
6d716ca8 | 5629 | { |
c05a9b68 RS |
5630 | /* If either operand is a NaN, the result is false with two |
5631 | exceptions: First, an NE_EXPR is true on NaNs, but that case | |
5632 | is already handled correctly since we will be inverting the | |
5633 | result for NE_EXPR. Second, if we had inverted a LE_EXPR | |
5634 | or a GE_EXPR into a LT_EXPR, we must return true so that it | |
5635 | will be inverted into false. */ | |
5636 | ||
5637 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg0)) | |
5638 | || REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))) | |
5639 | t1 = build_int_2 (invert && code == LT_EXPR, 0); | |
5640 | ||
5641 | else if (code == EQ_EXPR) | |
5642 | t1 = build_int_2 (REAL_VALUES_EQUAL (TREE_REAL_CST (arg0), | |
5643 | TREE_REAL_CST (arg1)), | |
5644 | 0); | |
6d716ca8 | 5645 | else |
c05a9b68 RS |
5646 | t1 = build_int_2 (REAL_VALUES_LESS (TREE_REAL_CST (arg0), |
5647 | TREE_REAL_CST (arg1)), | |
5648 | 0); | |
6d716ca8 RS |
5649 | } |
5650 | ||
c05a9b68 RS |
5651 | if (t1 == NULL_TREE) |
5652 | return t; | |
5653 | ||
5654 | if (invert) | |
5655 | TREE_INT_CST_LOW (t1) ^= 1; | |
5656 | ||
5657 | TREE_TYPE (t1) = type; | |
c651e1e0 MM |
5658 | if (TREE_CODE (type) == BOOLEAN_TYPE) |
5659 | return truthvalue_conversion (t1); | |
c05a9b68 | 5660 | return t1; |
6d716ca8 RS |
5661 | |
5662 | case COND_EXPR: | |
a5e9b124 JW |
5663 | /* Pedantic ANSI C says that a conditional expression is never an lvalue, |
5664 | so all simple results must be passed through pedantic_non_lvalue. */ | |
6d716ca8 | 5665 | if (TREE_CODE (arg0) == INTEGER_CST) |
a5e9b124 JW |
5666 | return pedantic_non_lvalue |
5667 | (TREE_OPERAND (t, (integer_zerop (arg0) ? 2 : 1))); | |
6d716ca8 | 5668 | else if (operand_equal_p (arg1, TREE_OPERAND (expr, 2), 0)) |
4ab3cb65 | 5669 | return pedantic_omit_one_operand (type, arg1, arg0); |
6d716ca8 | 5670 | |
c05a9b68 RS |
5671 | /* If the second operand is zero, invert the comparison and swap |
5672 | the second and third operands. Likewise if the second operand | |
5673 | is constant and the third is not or if the third operand is | |
5674 | equivalent to the first operand of the comparison. */ | |
6d716ca8 | 5675 | |
c05a9b68 RS |
5676 | if (integer_zerop (arg1) |
5677 | || (TREE_CONSTANT (arg1) && ! TREE_CONSTANT (TREE_OPERAND (t, 2))) | |
5678 | || (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' | |
5679 | && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0), | |
5680 | TREE_OPERAND (t, 2), | |
5681 | TREE_OPERAND (arg0, 1)))) | |
5682 | { | |
5683 | /* See if this can be inverted. If it can't, possibly because | |
5684 | it was a floating-point inequality comparison, don't do | |
5685 | anything. */ | |
5686 | tem = invert_truthvalue (arg0); | |
6d716ca8 | 5687 | |
c05a9b68 RS |
5688 | if (TREE_CODE (tem) != TRUTH_NOT_EXPR) |
5689 | { | |
cd7ece66 RK |
5690 | t = build (code, type, tem, |
5691 | TREE_OPERAND (t, 2), TREE_OPERAND (t, 1)); | |
5692 | arg0 = tem; | |
3a96b5eb | 5693 | arg1 = TREE_OPERAND (t, 2); |
3a96b5eb | 5694 | STRIP_NOPS (arg1); |
c05a9b68 RS |
5695 | } |
5696 | } | |
6d716ca8 | 5697 | |
c05a9b68 RS |
5698 | /* If we have A op B ? A : C, we may be able to convert this to a |
5699 | simpler expression, depending on the operation and the values | |
b5c52586 RS |
5700 | of B and C. IEEE floating point prevents this though, |
5701 | because A or B might be -0.0 or a NaN. */ | |
6d716ca8 | 5702 | |
c05a9b68 | 5703 | if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<' |
b5c52586 | 5704 | && (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
fab446b8 RK |
5705 | || ! FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 0))) |
5706 | || flag_fast_math) | |
c05a9b68 RS |
5707 | && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0), |
5708 | arg1, TREE_OPERAND (arg0, 1))) | |
6d716ca8 | 5709 | { |
c05a9b68 RS |
5710 | tree arg2 = TREE_OPERAND (t, 2); |
5711 | enum tree_code comp_code = TREE_CODE (arg0); | |
5712 | ||
3a96b5eb RK |
5713 | STRIP_NOPS (arg2); |
5714 | ||
c05a9b68 RS |
5715 | /* If we have A op 0 ? A : -A, this is A, -A, abs (A), or abs (-A), |
5716 | depending on the comparison operation. */ | |
68c6b3a9 DE |
5717 | if ((FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 1))) |
5718 | ? real_zerop (TREE_OPERAND (arg0, 1)) | |
5719 | : integer_zerop (TREE_OPERAND (arg0, 1))) | |
c05a9b68 RS |
5720 | && TREE_CODE (arg2) == NEGATE_EXPR |
5721 | && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0)) | |
5722 | switch (comp_code) | |
5723 | { | |
5724 | case EQ_EXPR: | |
a5e9b124 JW |
5725 | return pedantic_non_lvalue |
5726 | (fold (build1 (NEGATE_EXPR, type, arg1))); | |
c05a9b68 | 5727 | case NE_EXPR: |
a5e9b124 | 5728 | return pedantic_non_lvalue (convert (type, arg1)); |
c05a9b68 RS |
5729 | case GE_EXPR: |
5730 | case GT_EXPR: | |
a5e9b124 | 5731 | return pedantic_non_lvalue |
21403f14 RK |
5732 | (convert (type, fold (build1 (ABS_EXPR, |
5733 | TREE_TYPE (arg1), arg1)))); | |
c05a9b68 RS |
5734 | case LE_EXPR: |
5735 | case LT_EXPR: | |
a5e9b124 JW |
5736 | return pedantic_non_lvalue |
5737 | (fold (build1 (NEGATE_EXPR, type, | |
21403f14 RK |
5738 | convert (type, |
5739 | fold (build1 (ABS_EXPR, | |
5740 | TREE_TYPE (arg1), | |
5741 | arg1)))))); | |
e9a25f70 JL |
5742 | default: |
5743 | abort (); | |
c05a9b68 | 5744 | } |
6d716ca8 | 5745 | |
c05a9b68 RS |
5746 | /* If this is A != 0 ? A : 0, this is simply A. For ==, it is |
5747 | always zero. */ | |
6d716ca8 | 5748 | |
29ebe69a | 5749 | if (integer_zerop (TREE_OPERAND (arg0, 1)) && integer_zerop (arg2)) |
c05a9b68 RS |
5750 | { |
5751 | if (comp_code == NE_EXPR) | |
a5e9b124 | 5752 | return pedantic_non_lvalue (convert (type, arg1)); |
c05a9b68 | 5753 | else if (comp_code == EQ_EXPR) |
a5e9b124 | 5754 | return pedantic_non_lvalue (convert (type, integer_zero_node)); |
c05a9b68 RS |
5755 | } |
5756 | ||
5757 | /* If this is A op B ? A : B, this is either A, B, min (A, B), | |
5758 | or max (A, B), depending on the operation. */ | |
5759 | ||
5760 | if (operand_equal_for_comparison_p (TREE_OPERAND (arg0, 1), | |
5761 | arg2, TREE_OPERAND (arg0, 0))) | |
3a96b5eb RK |
5762 | { |
5763 | tree comp_op0 = TREE_OPERAND (arg0, 0); | |
5764 | tree comp_op1 = TREE_OPERAND (arg0, 1); | |
5765 | tree comp_type = TREE_TYPE (comp_op0); | |
5766 | ||
5767 | switch (comp_code) | |
5768 | { | |
5769 | case EQ_EXPR: | |
5770 | return pedantic_non_lvalue (convert (type, arg2)); | |
5771 | case NE_EXPR: | |
5772 | return pedantic_non_lvalue (convert (type, arg1)); | |
5773 | case LE_EXPR: | |
5774 | case LT_EXPR: | |
e9a25f70 JL |
5775 | /* In C++ a ?: expression can be an lvalue, so put the |
5776 | operand which will be used if they are equal first | |
5777 | so that we can convert this back to the | |
5778 | corresponding COND_EXPR. */ | |
5779 | return pedantic_non_lvalue | |
5780 | (convert (type, (fold (build (MIN_EXPR, comp_type, | |
5781 | (comp_code == LE_EXPR | |
5782 | ? comp_op0 : comp_op1), | |
5783 | (comp_code == LE_EXPR | |
5784 | ? comp_op1 : comp_op0)))))); | |
88a5cdb8 | 5785 | break; |
3a96b5eb RK |
5786 | case GE_EXPR: |
5787 | case GT_EXPR: | |
e9a25f70 JL |
5788 | return pedantic_non_lvalue |
5789 | (convert (type, fold (build (MAX_EXPR, comp_type, | |
5790 | (comp_code == GE_EXPR | |
5791 | ? comp_op0 : comp_op1), | |
5792 | (comp_code == GE_EXPR | |
5793 | ? comp_op1 : comp_op0))))); | |
88a5cdb8 | 5794 | break; |
e9a25f70 JL |
5795 | default: |
5796 | abort (); | |
3a96b5eb RK |
5797 | } |
5798 | } | |
c05a9b68 RS |
5799 | |
5800 | /* If this is A op C1 ? A : C2 with C1 and C2 constant integers, | |
5801 | we might still be able to simplify this. For example, | |
5802 | if C1 is one less or one more than C2, this might have started | |
53d2fb4f | 5803 | out as a MIN or MAX and been transformed by this function. |
7178e3af | 5804 | Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */ |
c05a9b68 | 5805 | |
7178e3af | 5806 | if (INTEGRAL_TYPE_P (type) |
53d2fb4f | 5807 | && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST |
c05a9b68 RS |
5808 | && TREE_CODE (arg2) == INTEGER_CST) |
5809 | switch (comp_code) | |
5810 | { | |
5811 | case EQ_EXPR: | |
5812 | /* We can replace A with C1 in this case. */ | |
cd7ece66 RK |
5813 | arg1 = convert (type, TREE_OPERAND (arg0, 1)); |
5814 | t = build (code, type, TREE_OPERAND (t, 0), arg1, | |
5815 | TREE_OPERAND (t, 2)); | |
c05a9b68 RS |
5816 | break; |
5817 | ||
5818 | case LT_EXPR: | |
5819 | /* If C1 is C2 + 1, this is min(A, C2). */ | |
5820 | if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), 1) | |
5821 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
5822 | const_binop (PLUS_EXPR, arg2, | |
91d33e36 | 5823 | integer_one_node, 0), 1)) |
a5e9b124 JW |
5824 | return pedantic_non_lvalue |
5825 | (fold (build (MIN_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
5826 | break; |
5827 | ||
5828 | case LE_EXPR: | |
5829 | /* If C1 is C2 - 1, this is min(A, C2). */ | |
5830 | if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), 1) | |
5831 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
5832 | const_binop (MINUS_EXPR, arg2, | |
91d33e36 | 5833 | integer_one_node, 0), 1)) |
a5e9b124 JW |
5834 | return pedantic_non_lvalue |
5835 | (fold (build (MIN_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
5836 | break; |
5837 | ||
5838 | case GT_EXPR: | |
5839 | /* If C1 is C2 - 1, this is max(A, C2). */ | |
5840 | if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type), 1) | |
5841 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
5842 | const_binop (MINUS_EXPR, arg2, | |
91d33e36 | 5843 | integer_one_node, 0), 1)) |
a5e9b124 JW |
5844 | return pedantic_non_lvalue |
5845 | (fold (build (MAX_EXPR, type, arg1, arg2))); | |
c05a9b68 RS |
5846 | break; |
5847 | ||
5848 | case GE_EXPR: | |
5849 | /* If C1 is C2 + 1, this is max(A, C2). */ | |
5850 | if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type), 1) | |
5851 | && operand_equal_p (TREE_OPERAND (arg0, 1), | |
5852 | const_binop (PLUS_EXPR, arg2, | |
91d33e36 | 5853 | integer_one_node, 0), 1)) |
a5e9b124 JW |
5854 | return pedantic_non_lvalue |
5855 | (fold (build (MAX_EXPR, type, arg1, arg2))); | |
c05a9b68 | 5856 | break; |
e9a25f70 JL |
5857 | case NE_EXPR: |
5858 | break; | |
5859 | default: | |
5860 | abort (); | |
c05a9b68 | 5861 | } |
6d716ca8 RS |
5862 | } |
5863 | ||
e1f56f62 RK |
5864 | /* If the second operand is simpler than the third, swap them |
5865 | since that produces better jump optimization results. */ | |
5866 | if ((TREE_CONSTANT (arg1) || TREE_CODE_CLASS (TREE_CODE (arg1)) == 'd' | |
5867 | || TREE_CODE (arg1) == SAVE_EXPR) | |
5868 | && ! (TREE_CONSTANT (TREE_OPERAND (t, 2)) | |
5869 | || TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (t, 2))) == 'd' | |
5870 | || TREE_CODE (TREE_OPERAND (t, 2)) == SAVE_EXPR)) | |
5871 | { | |
5872 | /* See if this can be inverted. If it can't, possibly because | |
5873 | it was a floating-point inequality comparison, don't do | |
5874 | anything. */ | |
5875 | tem = invert_truthvalue (arg0); | |
5876 | ||
5877 | if (TREE_CODE (tem) != TRUTH_NOT_EXPR) | |
5878 | { | |
cd7ece66 RK |
5879 | t = build (code, type, tem, |
5880 | TREE_OPERAND (t, 2), TREE_OPERAND (t, 1)); | |
5881 | arg0 = tem; | |
3a96b5eb | 5882 | arg1 = TREE_OPERAND (t, 2); |
3a96b5eb | 5883 | STRIP_NOPS (arg1); |
e1f56f62 RK |
5884 | } |
5885 | } | |
5886 | ||
c05a9b68 RS |
5887 | /* Convert A ? 1 : 0 to simply A. */ |
5888 | if (integer_onep (TREE_OPERAND (t, 1)) | |
5889 | && integer_zerop (TREE_OPERAND (t, 2)) | |
5890 | /* If we try to convert TREE_OPERAND (t, 0) to our type, the | |
5891 | call to fold will try to move the conversion inside | |
5892 | a COND, which will recurse. In that case, the COND_EXPR | |
5893 | is probably the best choice, so leave it alone. */ | |
5894 | && type == TREE_TYPE (arg0)) | |
a5e9b124 | 5895 | return pedantic_non_lvalue (arg0); |
6d716ca8 | 5896 | |
c05a9b68 RS |
5897 | /* Look for expressions of the form A & 2 ? 2 : 0. The result of this |
5898 | operation is simply A & 2. */ | |
6d716ca8 RS |
5899 | |
5900 | if (integer_zerop (TREE_OPERAND (t, 2)) | |
5901 | && TREE_CODE (arg0) == NE_EXPR | |
5902 | && integer_zerop (TREE_OPERAND (arg0, 1)) | |
c05a9b68 RS |
5903 | && integer_pow2p (arg1) |
5904 | && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR | |
5905 | && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1), | |
5906 | arg1, 1)) | |
a5e9b124 | 5907 | return pedantic_non_lvalue (convert (type, TREE_OPERAND (arg0, 0))); |
6d716ca8 | 5908 | |
6d716ca8 RS |
5909 | return t; |
5910 | ||
5911 | case COMPOUND_EXPR: | |
b7647895 JW |
5912 | /* When pedantic, a compound expression can be neither an lvalue |
5913 | nor an integer constant expression. */ | |
5914 | if (TREE_SIDE_EFFECTS (arg0) || pedantic) | |
d023bff9 RS |
5915 | return t; |
5916 | /* Don't let (0, 0) be null pointer constant. */ | |
5917 | if (integer_zerop (arg1)) | |
5918 | return non_lvalue (arg1); | |
5919 | return arg1; | |
6d716ca8 | 5920 | |
1cc1b11a RS |
5921 | case COMPLEX_EXPR: |
5922 | if (wins) | |
214d5b84 | 5923 | return build_complex (type, arg0, arg1); |
1cc1b11a RS |
5924 | return t; |
5925 | ||
5926 | case REALPART_EXPR: | |
a333b79f | 5927 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) |
1cc1b11a RS |
5928 | return t; |
5929 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
5930 | return omit_one_operand (type, TREE_OPERAND (arg0, 0), | |
5931 | TREE_OPERAND (arg0, 1)); | |
5932 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
5933 | return TREE_REALPART (arg0); | |
5934 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
a3279355 RK |
5935 | return fold (build (TREE_CODE (arg0), type, |
5936 | fold (build1 (REALPART_EXPR, type, | |
5937 | TREE_OPERAND (arg0, 0))), | |
5938 | fold (build1 (REALPART_EXPR, | |
5939 | type, TREE_OPERAND (arg0, 1))))); | |
1cc1b11a RS |
5940 | return t; |
5941 | ||
5942 | case IMAGPART_EXPR: | |
a333b79f | 5943 | if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE) |
1cc1b11a RS |
5944 | return convert (type, integer_zero_node); |
5945 | else if (TREE_CODE (arg0) == COMPLEX_EXPR) | |
5946 | return omit_one_operand (type, TREE_OPERAND (arg0, 1), | |
5947 | TREE_OPERAND (arg0, 0)); | |
5948 | else if (TREE_CODE (arg0) == COMPLEX_CST) | |
5949 | return TREE_IMAGPART (arg0); | |
5950 | else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) | |
a3279355 RK |
5951 | return fold (build (TREE_CODE (arg0), type, |
5952 | fold (build1 (IMAGPART_EXPR, type, | |
5953 | TREE_OPERAND (arg0, 0))), | |
5954 | fold (build1 (IMAGPART_EXPR, type, | |
5955 | TREE_OPERAND (arg0, 1))))); | |
1cc1b11a RS |
5956 | return t; |
5957 | ||
56c98e5b JM |
5958 | /* Pull arithmetic ops out of the CLEANUP_POINT_EXPR where |
5959 | appropriate. */ | |
5960 | case CLEANUP_POINT_EXPR: | |
b7f6588d | 5961 | if (! has_cleanups (arg0)) |
3ffcb234 | 5962 | return TREE_OPERAND (t, 0); |
56c98e5b JM |
5963 | |
5964 | { | |
5965 | enum tree_code code0 = TREE_CODE (arg0); | |
5966 | int kind0 = TREE_CODE_CLASS (code0); | |
5967 | tree arg00 = TREE_OPERAND (arg0, 0); | |
5968 | tree arg01; | |
5969 | ||
0982a4b8 | 5970 | if (kind0 == '1' || code0 == TRUTH_NOT_EXPR) |
56c98e5b JM |
5971 | return fold (build1 (code0, type, |
5972 | fold (build1 (CLEANUP_POINT_EXPR, | |
5973 | TREE_TYPE (arg00), arg00)))); | |
0982a4b8 JM |
5974 | |
5975 | if (kind0 == '<' || kind0 == '2' | |
5976 | || code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR | |
5977 | || code0 == TRUTH_AND_EXPR || code0 == TRUTH_OR_EXPR | |
5978 | || code0 == TRUTH_XOR_EXPR) | |
5979 | { | |
5980 | arg01 = TREE_OPERAND (arg0, 1); | |
5981 | ||
b7f6588d JM |
5982 | if (TREE_CONSTANT (arg00) |
5983 | || ((code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR) | |
5984 | && ! has_cleanups (arg00))) | |
0982a4b8 JM |
5985 | return fold (build (code0, type, arg00, |
5986 | fold (build1 (CLEANUP_POINT_EXPR, | |
5987 | TREE_TYPE (arg01), arg01)))); | |
5988 | ||
b7f6588d | 5989 | if (TREE_CONSTANT (arg01)) |
0982a4b8 JM |
5990 | return fold (build (code0, type, |
5991 | fold (build1 (CLEANUP_POINT_EXPR, | |
5992 | TREE_TYPE (arg00), arg00)), | |
5993 | arg01)); | |
5994 | } | |
56c98e5b JM |
5995 | |
5996 | return t; | |
5997 | } | |
5998 | ||
6d716ca8 RS |
5999 | default: |
6000 | return t; | |
6001 | } /* switch (code) */ | |
6002 | } | |
39dfb55a JL |
6003 | |
6004 | /* Determine if first argument is a multiple of second argument. | |
6005 | Return 0 if it is not, or is not easily determined to so be. | |
6006 | ||
6007 | An example of the sort of thing we care about (at this point -- | |
6008 | this routine could surely be made more general, and expanded | |
6009 | to do what the *_DIV_EXPR's fold() cases do now) is discovering | |
6010 | that | |
6011 | ||
6012 | SAVE_EXPR (I) * SAVE_EXPR (J * 8) | |
6013 | ||
6014 | is a multiple of | |
6015 | ||
6016 | SAVE_EXPR (J * 8) | |
6017 | ||
6018 | when we know that the two `SAVE_EXPR (J * 8)' nodes are the | |
6019 | same node (which means they will have the same value at run | |
6020 | time, even though we don't know when they'll be assigned). | |
6021 | ||
6022 | This code also handles discovering that | |
6023 | ||
6024 | SAVE_EXPR (I) * SAVE_EXPR (J * 8) | |
6025 | ||
6026 | is a multiple of | |
6027 | ||
6028 | 8 | |
6029 | ||
6030 | (of course) so we don't have to worry about dealing with a | |
6031 | possible remainder. | |
6032 | ||
6033 | Note that we _look_ inside a SAVE_EXPR only to determine | |
6034 | how it was calculated; it is not safe for fold() to do much | |
6035 | of anything else with the internals of a SAVE_EXPR, since | |
6036 | fold() cannot know when it will be evaluated at run time. | |
6037 | For example, the latter example above _cannot_ be implemented | |
6038 | as | |
6039 | ||
6040 | SAVE_EXPR (I) * J | |
6041 | ||
6042 | or any variant thereof, since the value of J at evaluation time | |
6043 | of the original SAVE_EXPR is not necessarily the same at the time | |
6044 | the new expression is evaluated. The only optimization of this | |
6045 | sort that would be valid is changing | |
6046 | ||
6047 | SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8) | |
6048 | divided by | |
6049 | 8 | |
6050 | ||
6051 | to | |
6052 | ||
6053 | SAVE_EXPR (I) * SAVE_EXPR (J) | |
6054 | ||
6055 | (where the same SAVE_EXPR (J) is used in the original and the | |
6056 | transformed version). */ | |
6057 | ||
6058 | static int | |
6059 | multiple_of_p (type, top, bottom) | |
6060 | tree type; | |
6061 | tree top; | |
6062 | tree bottom; | |
6063 | { | |
6064 | if (operand_equal_p (top, bottom, 0)) | |
6065 | return 1; | |
6066 | ||
6067 | if (TREE_CODE (type) != INTEGER_TYPE) | |
6068 | return 0; | |
6069 | ||
6070 | switch (TREE_CODE (top)) | |
6071 | { | |
6072 | case MULT_EXPR: | |
6073 | return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom) | |
6074 | || multiple_of_p (type, TREE_OPERAND (top, 1), bottom)); | |
6075 | ||
6076 | case PLUS_EXPR: | |
6077 | case MINUS_EXPR: | |
6078 | return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom) | |
6079 | && multiple_of_p (type, TREE_OPERAND (top, 1), bottom)); | |
6080 | ||
6081 | case NOP_EXPR: | |
6082 | /* Punt if conversion from non-integral or wider integral type. */ | |
6083 | if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE) | |
6084 | || (TYPE_PRECISION (type) | |
6085 | < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0))))) | |
6086 | return 0; | |
6087 | /* Fall through. */ | |
6088 | case SAVE_EXPR: | |
6089 | return multiple_of_p (type, TREE_OPERAND (top, 0), bottom); | |
6090 | ||
6091 | case INTEGER_CST: | |
6092 | if ((TREE_CODE (bottom) != INTEGER_CST) | |
6093 | || (tree_int_cst_sgn (top) < 0) | |
6094 | || (tree_int_cst_sgn (bottom) < 0)) | |
6095 | return 0; | |
6096 | return integer_zerop (const_binop (TRUNC_MOD_EXPR, | |
6097 | top, bottom, 0)); | |
6098 | ||
6099 | default: | |
6100 | return 0; | |
6101 | } | |
6102 | } | |
6103 | \f |