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1364018f | 1 | /* Chains of recurrences. |
7cf0dbf3 | 2 | Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 |
cfaf579d | 3 | Free Software Foundation, Inc. |
6b421feb | 4 | Contributed by Sebastian Pop <pop@cri.ensmp.fr> |
1364018f | 5 | |
6 | This file is part of GCC. | |
7 | ||
8 | GCC is free software; you can redistribute it and/or modify it under | |
9 | the terms of the GNU General Public License as published by the Free | |
8c4c00c1 | 10 | Software Foundation; either version 3, or (at your option) any later |
1364018f | 11 | version. |
12 | ||
13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
16 | for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
8c4c00c1 | 19 | along with GCC; see the file COPYING3. If not see |
20 | <http://www.gnu.org/licenses/>. */ | |
1364018f | 21 | |
22 | /* This file implements operations on chains of recurrences. Chains | |
23 | of recurrences are used for modeling evolution functions of scalar | |
24 | variables. | |
25 | */ | |
26 | ||
27 | #include "config.h" | |
28 | #include "system.h" | |
29 | #include "coretypes.h" | |
ce084dfc | 30 | #include "tree-pretty-print.h" |
b3786ab3 | 31 | #include "cfgloop.h" |
32 | #include "tree-flow.h" | |
1364018f | 33 | #include "tree-chrec.h" |
b9ed1410 | 34 | #include "dumpfile.h" |
a89ef955 | 35 | #include "params.h" |
9887dd18 | 36 | #include "tree-scalar-evolution.h" |
1364018f | 37 | |
1364018f | 38 | /* Extended folder for chrecs. */ |
39 | ||
40 | /* Determines whether CST is not a constant evolution. */ | |
41 | ||
42 | static inline bool | |
7ecb5bb2 | 43 | is_not_constant_evolution (const_tree cst) |
1364018f | 44 | { |
45 | return (TREE_CODE (cst) == POLYNOMIAL_CHREC); | |
46 | } | |
47 | ||
48 | /* Fold CODE for a polynomial function and a constant. */ | |
49 | ||
48e1416a | 50 | static inline tree |
51 | chrec_fold_poly_cst (enum tree_code code, | |
52 | tree type, | |
53 | tree poly, | |
1364018f | 54 | tree cst) |
55 | { | |
8c0963c4 | 56 | gcc_assert (poly); |
57 | gcc_assert (cst); | |
58 | gcc_assert (TREE_CODE (poly) == POLYNOMIAL_CHREC); | |
59 | gcc_assert (!is_not_constant_evolution (cst)); | |
f84a688a | 60 | gcc_assert (type == chrec_type (poly)); |
61 | ||
1364018f | 62 | switch (code) |
63 | { | |
64 | case PLUS_EXPR: | |
48e1416a | 65 | return build_polynomial_chrec |
66 | (CHREC_VARIABLE (poly), | |
1364018f | 67 | chrec_fold_plus (type, CHREC_LEFT (poly), cst), |
68 | CHREC_RIGHT (poly)); | |
48e1416a | 69 | |
1364018f | 70 | case MINUS_EXPR: |
48e1416a | 71 | return build_polynomial_chrec |
72 | (CHREC_VARIABLE (poly), | |
1364018f | 73 | chrec_fold_minus (type, CHREC_LEFT (poly), cst), |
74 | CHREC_RIGHT (poly)); | |
48e1416a | 75 | |
1364018f | 76 | case MULT_EXPR: |
48e1416a | 77 | return build_polynomial_chrec |
78 | (CHREC_VARIABLE (poly), | |
1364018f | 79 | chrec_fold_multiply (type, CHREC_LEFT (poly), cst), |
80 | chrec_fold_multiply (type, CHREC_RIGHT (poly), cst)); | |
48e1416a | 81 | |
1364018f | 82 | default: |
83 | return chrec_dont_know; | |
84 | } | |
85 | } | |
86 | ||
87 | /* Fold the addition of two polynomial functions. */ | |
88 | ||
48e1416a | 89 | static inline tree |
90 | chrec_fold_plus_poly_poly (enum tree_code code, | |
91 | tree type, | |
92 | tree poly0, | |
1364018f | 93 | tree poly1) |
94 | { | |
95 | tree left, right; | |
3bbbcdff | 96 | struct loop *loop0 = get_chrec_loop (poly0); |
97 | struct loop *loop1 = get_chrec_loop (poly1); | |
a845d317 | 98 | tree rtype = code == POINTER_PLUS_EXPR ? chrec_type (poly1) : type; |
8c0963c4 | 99 | |
100 | gcc_assert (poly0); | |
101 | gcc_assert (poly1); | |
102 | gcc_assert (TREE_CODE (poly0) == POLYNOMIAL_CHREC); | |
103 | gcc_assert (TREE_CODE (poly1) == POLYNOMIAL_CHREC); | |
0de36bdb | 104 | if (POINTER_TYPE_P (chrec_type (poly0))) |
a845d317 | 105 | gcc_assert (ptrofftype_p (chrec_type (poly1))); |
0de36bdb | 106 | else |
107 | gcc_assert (chrec_type (poly0) == chrec_type (poly1)); | |
f84a688a | 108 | gcc_assert (type == chrec_type (poly0)); |
48e1416a | 109 | |
1364018f | 110 | /* |
111 | {a, +, b}_1 + {c, +, d}_2 -> {{a, +, b}_1 + c, +, d}_2, | |
112 | {a, +, b}_2 + {c, +, d}_1 -> {{c, +, d}_1 + a, +, b}_2, | |
113 | {a, +, b}_x + {c, +, d}_x -> {a+c, +, b+d}_x. */ | |
3bbbcdff | 114 | if (flow_loop_nested_p (loop0, loop1)) |
1364018f | 115 | { |
0de36bdb | 116 | if (code == PLUS_EXPR || code == POINTER_PLUS_EXPR) |
48e1416a | 117 | return build_polynomial_chrec |
118 | (CHREC_VARIABLE (poly1), | |
1364018f | 119 | chrec_fold_plus (type, poly0, CHREC_LEFT (poly1)), |
120 | CHREC_RIGHT (poly1)); | |
121 | else | |
48e1416a | 122 | return build_polynomial_chrec |
123 | (CHREC_VARIABLE (poly1), | |
1364018f | 124 | chrec_fold_minus (type, poly0, CHREC_LEFT (poly1)), |
48e1416a | 125 | chrec_fold_multiply (type, CHREC_RIGHT (poly1), |
eb105b17 | 126 | SCALAR_FLOAT_TYPE_P (type) |
127 | ? build_real (type, dconstm1) | |
128 | : build_int_cst_type (type, -1))); | |
1364018f | 129 | } |
48e1416a | 130 | |
3bbbcdff | 131 | if (flow_loop_nested_p (loop1, loop0)) |
1364018f | 132 | { |
0de36bdb | 133 | if (code == PLUS_EXPR || code == POINTER_PLUS_EXPR) |
48e1416a | 134 | return build_polynomial_chrec |
135 | (CHREC_VARIABLE (poly0), | |
1364018f | 136 | chrec_fold_plus (type, CHREC_LEFT (poly0), poly1), |
137 | CHREC_RIGHT (poly0)); | |
138 | else | |
48e1416a | 139 | return build_polynomial_chrec |
140 | (CHREC_VARIABLE (poly0), | |
1364018f | 141 | chrec_fold_minus (type, CHREC_LEFT (poly0), poly1), |
142 | CHREC_RIGHT (poly0)); | |
143 | } | |
48e1416a | 144 | |
3bbbcdff | 145 | /* This function should never be called for chrecs of loops that |
146 | do not belong to the same loop nest. */ | |
147 | gcc_assert (loop0 == loop1); | |
148 | ||
0de36bdb | 149 | if (code == PLUS_EXPR || code == POINTER_PLUS_EXPR) |
1364018f | 150 | { |
48e1416a | 151 | left = chrec_fold_plus |
1364018f | 152 | (type, CHREC_LEFT (poly0), CHREC_LEFT (poly1)); |
48e1416a | 153 | right = chrec_fold_plus |
0de36bdb | 154 | (rtype, CHREC_RIGHT (poly0), CHREC_RIGHT (poly1)); |
1364018f | 155 | } |
156 | else | |
157 | { | |
48e1416a | 158 | left = chrec_fold_minus |
1364018f | 159 | (type, CHREC_LEFT (poly0), CHREC_LEFT (poly1)); |
48e1416a | 160 | right = chrec_fold_minus |
1364018f | 161 | (type, CHREC_RIGHT (poly0), CHREC_RIGHT (poly1)); |
162 | } | |
163 | ||
164 | if (chrec_zerop (right)) | |
165 | return left; | |
166 | else | |
48e1416a | 167 | return build_polynomial_chrec |
168 | (CHREC_VARIABLE (poly0), left, right); | |
1364018f | 169 | } |
170 | ||
171 | \f | |
172 | ||
173 | /* Fold the multiplication of two polynomial functions. */ | |
174 | ||
48e1416a | 175 | static inline tree |
176 | chrec_fold_multiply_poly_poly (tree type, | |
177 | tree poly0, | |
1364018f | 178 | tree poly1) |
179 | { | |
20a25e6c | 180 | tree t0, t1, t2; |
181 | int var; | |
3bbbcdff | 182 | struct loop *loop0 = get_chrec_loop (poly0); |
183 | struct loop *loop1 = get_chrec_loop (poly1); | |
20a25e6c | 184 | |
8c0963c4 | 185 | gcc_assert (poly0); |
186 | gcc_assert (poly1); | |
187 | gcc_assert (TREE_CODE (poly0) == POLYNOMIAL_CHREC); | |
188 | gcc_assert (TREE_CODE (poly1) == POLYNOMIAL_CHREC); | |
f84a688a | 189 | gcc_assert (chrec_type (poly0) == chrec_type (poly1)); |
190 | gcc_assert (type == chrec_type (poly0)); | |
48e1416a | 191 | |
1364018f | 192 | /* {a, +, b}_1 * {c, +, d}_2 -> {c*{a, +, b}_1, +, d}_2, |
193 | {a, +, b}_2 * {c, +, d}_1 -> {a*{c, +, d}_1, +, b}_2, | |
194 | {a, +, b}_x * {c, +, d}_x -> {a*c, +, a*d + b*c + b*d, +, 2*b*d}_x. */ | |
3bbbcdff | 195 | if (flow_loop_nested_p (loop0, loop1)) |
1364018f | 196 | /* poly0 is a constant wrt. poly1. */ |
48e1416a | 197 | return build_polynomial_chrec |
198 | (CHREC_VARIABLE (poly1), | |
1364018f | 199 | chrec_fold_multiply (type, CHREC_LEFT (poly1), poly0), |
200 | CHREC_RIGHT (poly1)); | |
48e1416a | 201 | |
3bbbcdff | 202 | if (flow_loop_nested_p (loop1, loop0)) |
1364018f | 203 | /* poly1 is a constant wrt. poly0. */ |
48e1416a | 204 | return build_polynomial_chrec |
205 | (CHREC_VARIABLE (poly0), | |
1364018f | 206 | chrec_fold_multiply (type, CHREC_LEFT (poly0), poly1), |
207 | CHREC_RIGHT (poly0)); | |
48e1416a | 208 | |
3bbbcdff | 209 | gcc_assert (loop0 == loop1); |
210 | ||
1364018f | 211 | /* poly0 and poly1 are two polynomials in the same variable, |
212 | {a, +, b}_x * {c, +, d}_x -> {a*c, +, a*d + b*c + b*d, +, 2*b*d}_x. */ | |
48e1416a | 213 | |
20a25e6c | 214 | /* "a*c". */ |
215 | t0 = chrec_fold_multiply (type, CHREC_LEFT (poly0), CHREC_LEFT (poly1)); | |
216 | ||
0f0057aa | 217 | /* "a*d + b*c". */ |
20a25e6c | 218 | t1 = chrec_fold_multiply (type, CHREC_LEFT (poly0), CHREC_RIGHT (poly1)); |
219 | t1 = chrec_fold_plus (type, t1, chrec_fold_multiply (type, | |
220 | CHREC_RIGHT (poly0), | |
221 | CHREC_LEFT (poly1))); | |
0f0057aa | 222 | /* "b*d". */ |
20a25e6c | 223 | t2 = chrec_fold_multiply (type, CHREC_RIGHT (poly0), CHREC_RIGHT (poly1)); |
0f0057aa | 224 | /* "a*d + b*c + b*d". */ |
225 | t1 = chrec_fold_plus (type, t1, t2); | |
226 | /* "2*b*d". */ | |
eb105b17 | 227 | t2 = chrec_fold_multiply (type, SCALAR_FLOAT_TYPE_P (type) |
228 | ? build_real (type, dconst2) | |
05db596e | 229 | : build_int_cst (type, 2), t2); |
20a25e6c | 230 | |
231 | var = CHREC_VARIABLE (poly0); | |
232 | return build_polynomial_chrec (var, t0, | |
233 | build_polynomial_chrec (var, t1, t2)); | |
1364018f | 234 | } |
235 | ||
236 | /* When the operands are automatically_generated_chrec_p, the fold has | |
237 | to respect the semantics of the operands. */ | |
238 | ||
48e1416a | 239 | static inline tree |
240 | chrec_fold_automatically_generated_operands (tree op0, | |
1364018f | 241 | tree op1) |
242 | { | |
243 | if (op0 == chrec_dont_know | |
244 | || op1 == chrec_dont_know) | |
245 | return chrec_dont_know; | |
48e1416a | 246 | |
1364018f | 247 | if (op0 == chrec_known |
248 | || op1 == chrec_known) | |
249 | return chrec_known; | |
48e1416a | 250 | |
1364018f | 251 | if (op0 == chrec_not_analyzed_yet |
252 | || op1 == chrec_not_analyzed_yet) | |
253 | return chrec_not_analyzed_yet; | |
48e1416a | 254 | |
fbf0afd1 | 255 | /* The default case produces a safe result. */ |
1364018f | 256 | return chrec_dont_know; |
257 | } | |
258 | ||
259 | /* Fold the addition of two chrecs. */ | |
260 | ||
261 | static tree | |
48e1416a | 262 | chrec_fold_plus_1 (enum tree_code code, tree type, |
f84a688a | 263 | tree op0, tree op1) |
1364018f | 264 | { |
265 | if (automatically_generated_chrec_p (op0) | |
266 | || automatically_generated_chrec_p (op1)) | |
267 | return chrec_fold_automatically_generated_operands (op0, op1); | |
48e1416a | 268 | |
1364018f | 269 | switch (TREE_CODE (op0)) |
270 | { | |
271 | case POLYNOMIAL_CHREC: | |
272 | switch (TREE_CODE (op1)) | |
273 | { | |
274 | case POLYNOMIAL_CHREC: | |
275 | return chrec_fold_plus_poly_poly (code, type, op0, op1); | |
276 | ||
f2a8ffd0 | 277 | CASE_CONVERT: |
278 | if (tree_contains_chrecs (op1, NULL)) | |
279 | return chrec_dont_know; | |
280 | ||
1364018f | 281 | default: |
0de36bdb | 282 | if (code == PLUS_EXPR || code == POINTER_PLUS_EXPR) |
48e1416a | 283 | return build_polynomial_chrec |
284 | (CHREC_VARIABLE (op0), | |
1364018f | 285 | chrec_fold_plus (type, CHREC_LEFT (op0), op1), |
286 | CHREC_RIGHT (op0)); | |
287 | else | |
48e1416a | 288 | return build_polynomial_chrec |
289 | (CHREC_VARIABLE (op0), | |
1364018f | 290 | chrec_fold_minus (type, CHREC_LEFT (op0), op1), |
291 | CHREC_RIGHT (op0)); | |
292 | } | |
293 | ||
f2a8ffd0 | 294 | CASE_CONVERT: |
295 | if (tree_contains_chrecs (op0, NULL)) | |
296 | return chrec_dont_know; | |
297 | ||
1364018f | 298 | default: |
299 | switch (TREE_CODE (op1)) | |
300 | { | |
301 | case POLYNOMIAL_CHREC: | |
0de36bdb | 302 | if (code == PLUS_EXPR || code == POINTER_PLUS_EXPR) |
48e1416a | 303 | return build_polynomial_chrec |
304 | (CHREC_VARIABLE (op1), | |
1364018f | 305 | chrec_fold_plus (type, op0, CHREC_LEFT (op1)), |
306 | CHREC_RIGHT (op1)); | |
307 | else | |
48e1416a | 308 | return build_polynomial_chrec |
309 | (CHREC_VARIABLE (op1), | |
1364018f | 310 | chrec_fold_minus (type, op0, CHREC_LEFT (op1)), |
48e1416a | 311 | chrec_fold_multiply (type, CHREC_RIGHT (op1), |
eb105b17 | 312 | SCALAR_FLOAT_TYPE_P (type) |
313 | ? build_real (type, dconstm1) | |
314 | : build_int_cst_type (type, -1))); | |
1364018f | 315 | |
f2a8ffd0 | 316 | CASE_CONVERT: |
317 | if (tree_contains_chrecs (op1, NULL)) | |
318 | return chrec_dont_know; | |
319 | ||
1364018f | 320 | default: |
a89ef955 | 321 | { |
322 | int size = 0; | |
323 | if ((tree_contains_chrecs (op0, &size) | |
324 | || tree_contains_chrecs (op1, &size)) | |
325 | && size < PARAM_VALUE (PARAM_SCEV_MAX_EXPR_SIZE)) | |
326 | return build2 (code, type, op0, op1); | |
327 | else if (size < PARAM_VALUE (PARAM_SCEV_MAX_EXPR_SIZE)) | |
a0553bff | 328 | { |
329 | if (code == POINTER_PLUS_EXPR) | |
330 | return fold_build_pointer_plus (fold_convert (type, op0), | |
331 | op1); | |
332 | else | |
333 | return fold_build2 (code, type, | |
334 | fold_convert (type, op0), | |
335 | fold_convert (type, op1)); | |
336 | } | |
a89ef955 | 337 | else |
338 | return chrec_dont_know; | |
339 | } | |
1364018f | 340 | } |
341 | } | |
342 | } | |
343 | ||
344 | /* Fold the addition of two chrecs. */ | |
345 | ||
346 | tree | |
48e1416a | 347 | chrec_fold_plus (tree type, |
1364018f | 348 | tree op0, |
349 | tree op1) | |
350 | { | |
0de36bdb | 351 | enum tree_code code; |
f84a688a | 352 | if (automatically_generated_chrec_p (op0) |
353 | || automatically_generated_chrec_p (op1)) | |
354 | return chrec_fold_automatically_generated_operands (op0, op1); | |
355 | ||
1364018f | 356 | if (integer_zerop (op0)) |
75a70cf9 | 357 | return chrec_convert (type, op1, NULL); |
1364018f | 358 | if (integer_zerop (op1)) |
75a70cf9 | 359 | return chrec_convert (type, op0, NULL); |
0de36bdb | 360 | |
361 | if (POINTER_TYPE_P (type)) | |
362 | code = POINTER_PLUS_EXPR; | |
363 | else | |
364 | code = PLUS_EXPR; | |
48e1416a | 365 | |
0de36bdb | 366 | return chrec_fold_plus_1 (code, type, op0, op1); |
1364018f | 367 | } |
368 | ||
369 | /* Fold the subtraction of two chrecs. */ | |
370 | ||
48e1416a | 371 | tree |
372 | chrec_fold_minus (tree type, | |
373 | tree op0, | |
1364018f | 374 | tree op1) |
375 | { | |
f84a688a | 376 | if (automatically_generated_chrec_p (op0) |
377 | || automatically_generated_chrec_p (op1)) | |
378 | return chrec_fold_automatically_generated_operands (op0, op1); | |
379 | ||
1364018f | 380 | if (integer_zerop (op1)) |
381 | return op0; | |
48e1416a | 382 | |
1364018f | 383 | return chrec_fold_plus_1 (MINUS_EXPR, type, op0, op1); |
384 | } | |
385 | ||
386 | /* Fold the multiplication of two chrecs. */ | |
387 | ||
388 | tree | |
48e1416a | 389 | chrec_fold_multiply (tree type, |
1364018f | 390 | tree op0, |
391 | tree op1) | |
392 | { | |
393 | if (automatically_generated_chrec_p (op0) | |
394 | || automatically_generated_chrec_p (op1)) | |
395 | return chrec_fold_automatically_generated_operands (op0, op1); | |
48e1416a | 396 | |
1364018f | 397 | switch (TREE_CODE (op0)) |
398 | { | |
399 | case POLYNOMIAL_CHREC: | |
400 | switch (TREE_CODE (op1)) | |
401 | { | |
402 | case POLYNOMIAL_CHREC: | |
403 | return chrec_fold_multiply_poly_poly (type, op0, op1); | |
48e1416a | 404 | |
f2a8ffd0 | 405 | CASE_CONVERT: |
406 | if (tree_contains_chrecs (op1, NULL)) | |
407 | return chrec_dont_know; | |
408 | ||
1364018f | 409 | default: |
410 | if (integer_onep (op1)) | |
411 | return op0; | |
412 | if (integer_zerop (op1)) | |
05db596e | 413 | return build_int_cst (type, 0); |
48e1416a | 414 | |
415 | return build_polynomial_chrec | |
416 | (CHREC_VARIABLE (op0), | |
1364018f | 417 | chrec_fold_multiply (type, CHREC_LEFT (op0), op1), |
418 | chrec_fold_multiply (type, CHREC_RIGHT (op0), op1)); | |
419 | } | |
48e1416a | 420 | |
f2a8ffd0 | 421 | CASE_CONVERT: |
422 | if (tree_contains_chrecs (op0, NULL)) | |
423 | return chrec_dont_know; | |
424 | ||
1364018f | 425 | default: |
426 | if (integer_onep (op0)) | |
427 | return op1; | |
48e1416a | 428 | |
1364018f | 429 | if (integer_zerop (op0)) |
05db596e | 430 | return build_int_cst (type, 0); |
48e1416a | 431 | |
1364018f | 432 | switch (TREE_CODE (op1)) |
433 | { | |
434 | case POLYNOMIAL_CHREC: | |
48e1416a | 435 | return build_polynomial_chrec |
436 | (CHREC_VARIABLE (op1), | |
1364018f | 437 | chrec_fold_multiply (type, CHREC_LEFT (op1), op0), |
438 | chrec_fold_multiply (type, CHREC_RIGHT (op1), op0)); | |
48e1416a | 439 | |
f2a8ffd0 | 440 | CASE_CONVERT: |
441 | if (tree_contains_chrecs (op1, NULL)) | |
442 | return chrec_dont_know; | |
443 | ||
1364018f | 444 | default: |
445 | if (integer_onep (op1)) | |
446 | return op0; | |
447 | if (integer_zerop (op1)) | |
05db596e | 448 | return build_int_cst (type, 0); |
a89ef955 | 449 | return fold_build2 (MULT_EXPR, type, op0, op1); |
1364018f | 450 | } |
451 | } | |
452 | } | |
453 | ||
454 | \f | |
455 | ||
456 | /* Operations. */ | |
457 | ||
9353326d | 458 | /* Evaluate the binomial coefficient. Return NULL_TREE if the intermediate |
459 | calculation overflows, otherwise return C(n,k) with type TYPE. */ | |
460 | ||
48e1416a | 461 | static tree |
9353326d | 462 | tree_fold_binomial (tree type, tree n, unsigned int k) |
1364018f | 463 | { |
d67b7119 | 464 | double_int num, denom, idx, di_res; |
465 | bool overflow; | |
9353326d | 466 | unsigned int i; |
467 | tree res; | |
468 | ||
469 | /* Handle the most frequent cases. */ | |
470 | if (k == 0) | |
471 | return build_int_cst (type, 1); | |
472 | if (k == 1) | |
473 | return fold_convert (type, n); | |
474 | ||
d67b7119 | 475 | /* Numerator = n. */ |
476 | num = TREE_INT_CST (n); | |
477 | ||
9353326d | 478 | /* Check that k <= n. */ |
d67b7119 | 479 | if (num.ult (double_int::from_uhwi (k))) |
9353326d | 480 | return NULL_TREE; |
481 | ||
9353326d | 482 | /* Denominator = 2. */ |
d67b7119 | 483 | denom = double_int::from_uhwi (2); |
9353326d | 484 | |
485 | /* Index = Numerator-1. */ | |
d67b7119 | 486 | idx = num - double_int_one; |
1364018f | 487 | |
9353326d | 488 | /* Numerator = Numerator*Index = n*(n-1). */ |
d67b7119 | 489 | num = num.mul_with_sign (idx, false, &overflow); |
490 | if (overflow) | |
9353326d | 491 | return NULL_TREE; |
1364018f | 492 | |
9353326d | 493 | for (i = 3; i <= k; i++) |
494 | { | |
495 | /* Index--. */ | |
d67b7119 | 496 | --idx; |
9353326d | 497 | |
498 | /* Numerator *= Index. */ | |
d67b7119 | 499 | num = num.mul_with_sign (idx, false, &overflow); |
500 | if (overflow) | |
9353326d | 501 | return NULL_TREE; |
502 | ||
503 | /* Denominator *= i. */ | |
d67b7119 | 504 | denom *= double_int::from_uhwi (i); |
9353326d | 505 | } |
506 | ||
507 | /* Result = Numerator / Denominator. */ | |
d67b7119 | 508 | di_res = num.div (denom, true, EXACT_DIV_EXPR); |
509 | res = build_int_cst_wide (type, di_res.low, di_res.high); | |
9353326d | 510 | return int_fits_type_p (res, type) ? res : NULL_TREE; |
1364018f | 511 | } |
512 | ||
513 | /* Helper function. Use the Newton's interpolating formula for | |
514 | evaluating the value of the evolution function. */ | |
515 | ||
48e1416a | 516 | static tree |
9353326d | 517 | chrec_evaluate (unsigned var, tree chrec, tree n, unsigned int k) |
1364018f | 518 | { |
9353326d | 519 | tree arg0, arg1, binomial_n_k; |
520 | tree type = TREE_TYPE (chrec); | |
3bbbcdff | 521 | struct loop *var_loop = get_loop (var); |
9353326d | 522 | |
523 | while (TREE_CODE (chrec) == POLYNOMIAL_CHREC | |
3bbbcdff | 524 | && flow_loop_nested_p (var_loop, get_chrec_loop (chrec))) |
9353326d | 525 | chrec = CHREC_LEFT (chrec); |
526 | ||
527 | if (TREE_CODE (chrec) == POLYNOMIAL_CHREC | |
528 | && CHREC_VARIABLE (chrec) == var) | |
1364018f | 529 | { |
72aad60a | 530 | arg1 = chrec_evaluate (var, CHREC_RIGHT (chrec), n, k + 1); |
531 | if (arg1 == chrec_dont_know) | |
9353326d | 532 | return chrec_dont_know; |
533 | binomial_n_k = tree_fold_binomial (type, n, k); | |
534 | if (!binomial_n_k) | |
535 | return chrec_dont_know; | |
72aad60a | 536 | arg0 = fold_build2 (MULT_EXPR, type, |
a89ef955 | 537 | CHREC_LEFT (chrec), binomial_n_k); |
9353326d | 538 | return chrec_fold_plus (type, arg0, arg1); |
1364018f | 539 | } |
9353326d | 540 | |
541 | binomial_n_k = tree_fold_binomial (type, n, k); | |
542 | if (!binomial_n_k) | |
543 | return chrec_dont_know; | |
48e1416a | 544 | |
a89ef955 | 545 | return fold_build2 (MULT_EXPR, type, chrec, binomial_n_k); |
1364018f | 546 | } |
547 | ||
48e1416a | 548 | /* Evaluates "CHREC (X)" when the varying variable is VAR. |
549 | Example: Given the following parameters, | |
550 | ||
1364018f | 551 | var = 1 |
552 | chrec = {3, +, 4}_1 | |
553 | x = 10 | |
48e1416a | 554 | |
555 | The result is given by the Newton's interpolating formula: | |
1364018f | 556 | 3 * \binom{10}{0} + 4 * \binom{10}{1}. |
557 | */ | |
558 | ||
48e1416a | 559 | tree |
1364018f | 560 | chrec_apply (unsigned var, |
48e1416a | 561 | tree chrec, |
1364018f | 562 | tree x) |
563 | { | |
564 | tree type = chrec_type (chrec); | |
565 | tree res = chrec_dont_know; | |
566 | ||
567 | if (automatically_generated_chrec_p (chrec) | |
568 | || automatically_generated_chrec_p (x) | |
569 | ||
570 | /* When the symbols are defined in an outer loop, it is possible | |
571 | to symbolically compute the apply, since the symbols are | |
572 | constants with respect to the varying loop. */ | |
553b9523 | 573 | || chrec_contains_symbols_defined_in_loop (chrec, var)) |
1364018f | 574 | return chrec_dont_know; |
48e1416a | 575 | |
487a9bc1 | 576 | if (dump_file && (dump_flags & TDF_SCEV)) |
1364018f | 577 | fprintf (dump_file, "(chrec_apply \n"); |
578 | ||
dd2a65b3 | 579 | if (TREE_CODE (x) == INTEGER_CST && SCALAR_FLOAT_TYPE_P (type)) |
580 | x = build_real_from_int_cst (type, x); | |
581 | ||
9e4cd968 | 582 | switch (TREE_CODE (chrec)) |
1364018f | 583 | { |
9e4cd968 | 584 | case POLYNOMIAL_CHREC: |
585 | if (evolution_function_is_affine_p (chrec)) | |
586 | { | |
587 | if (CHREC_VARIABLE (chrec) != var) | |
588 | return build_polynomial_chrec | |
589 | (CHREC_VARIABLE (chrec), | |
590 | chrec_apply (var, CHREC_LEFT (chrec), x), | |
591 | chrec_apply (var, CHREC_RIGHT (chrec), x)); | |
592 | ||
593 | /* "{a, +, b} (x)" -> "a + b*x". */ | |
594 | x = chrec_convert_rhs (type, x, NULL); | |
595 | res = chrec_fold_multiply (TREE_TYPE (x), CHREC_RIGHT (chrec), x); | |
596 | res = chrec_fold_plus (type, CHREC_LEFT (chrec), res); | |
597 | } | |
598 | else if (TREE_CODE (x) == INTEGER_CST | |
599 | && tree_int_cst_sgn (x) == 1) | |
600 | /* testsuite/.../ssa-chrec-38.c. */ | |
601 | res = chrec_evaluate (var, chrec, x, 0); | |
602 | else | |
603 | res = chrec_dont_know; | |
604 | break; | |
48e1416a | 605 | |
9e4cd968 | 606 | CASE_CONVERT: |
607 | res = chrec_convert (TREE_TYPE (chrec), | |
608 | chrec_apply (var, TREE_OPERAND (chrec, 0), x), | |
609 | NULL); | |
610 | break; | |
48e1416a | 611 | |
9e4cd968 | 612 | default: |
613 | res = chrec; | |
614 | break; | |
615 | } | |
48e1416a | 616 | |
487a9bc1 | 617 | if (dump_file && (dump_flags & TDF_SCEV)) |
1364018f | 618 | { |
619 | fprintf (dump_file, " (varying_loop = %d\n", var); | |
620 | fprintf (dump_file, ")\n (chrec = "); | |
621 | print_generic_expr (dump_file, chrec, 0); | |
622 | fprintf (dump_file, ")\n (x = "); | |
623 | print_generic_expr (dump_file, x, 0); | |
624 | fprintf (dump_file, ")\n (res = "); | |
625 | print_generic_expr (dump_file, res, 0); | |
626 | fprintf (dump_file, "))\n"); | |
627 | } | |
48e1416a | 628 | |
1364018f | 629 | return res; |
630 | } | |
631 | ||
4ed27c8e | 632 | /* For a given CHREC and an induction variable map IV_MAP that maps |
633 | (loop->num, expr) for every loop number of the current_loops an | |
634 | expression, calls chrec_apply when the expression is not NULL. */ | |
635 | ||
636 | tree | |
f1f41a6c | 637 | chrec_apply_map (tree chrec, vec<tree> iv_map) |
4ed27c8e | 638 | { |
639 | int i; | |
640 | tree expr; | |
641 | ||
f1f41a6c | 642 | FOR_EACH_VEC_ELT (iv_map, i, expr) |
4ed27c8e | 643 | if (expr) |
644 | chrec = chrec_apply (i, chrec, expr); | |
645 | ||
646 | return chrec; | |
647 | } | |
648 | ||
1364018f | 649 | /* Replaces the initial condition in CHREC with INIT_COND. */ |
650 | ||
48e1416a | 651 | tree |
652 | chrec_replace_initial_condition (tree chrec, | |
1364018f | 653 | tree init_cond) |
654 | { | |
655 | if (automatically_generated_chrec_p (chrec)) | |
656 | return chrec; | |
f84a688a | 657 | |
658 | gcc_assert (chrec_type (chrec) == chrec_type (init_cond)); | |
659 | ||
1364018f | 660 | switch (TREE_CODE (chrec)) |
661 | { | |
662 | case POLYNOMIAL_CHREC: | |
48e1416a | 663 | return build_polynomial_chrec |
1364018f | 664 | (CHREC_VARIABLE (chrec), |
665 | chrec_replace_initial_condition (CHREC_LEFT (chrec), init_cond), | |
666 | CHREC_RIGHT (chrec)); | |
48e1416a | 667 | |
1364018f | 668 | default: |
669 | return init_cond; | |
670 | } | |
671 | } | |
672 | ||
673 | /* Returns the initial condition of a given CHREC. */ | |
674 | ||
48e1416a | 675 | tree |
1364018f | 676 | initial_condition (tree chrec) |
677 | { | |
678 | if (automatically_generated_chrec_p (chrec)) | |
679 | return chrec; | |
48e1416a | 680 | |
1364018f | 681 | if (TREE_CODE (chrec) == POLYNOMIAL_CHREC) |
682 | return initial_condition (CHREC_LEFT (chrec)); | |
683 | else | |
684 | return chrec; | |
685 | } | |
686 | ||
687 | /* Returns a univariate function that represents the evolution in | |
688 | LOOP_NUM. Mask the evolution of any other loop. */ | |
689 | ||
48e1416a | 690 | tree |
691 | hide_evolution_in_other_loops_than_loop (tree chrec, | |
1364018f | 692 | unsigned loop_num) |
693 | { | |
3bbbcdff | 694 | struct loop *loop = get_loop (loop_num), *chloop; |
1364018f | 695 | if (automatically_generated_chrec_p (chrec)) |
696 | return chrec; | |
48e1416a | 697 | |
1364018f | 698 | switch (TREE_CODE (chrec)) |
699 | { | |
700 | case POLYNOMIAL_CHREC: | |
3bbbcdff | 701 | chloop = get_chrec_loop (chrec); |
702 | ||
703 | if (chloop == loop) | |
48e1416a | 704 | return build_polynomial_chrec |
705 | (loop_num, | |
706 | hide_evolution_in_other_loops_than_loop (CHREC_LEFT (chrec), | |
707 | loop_num), | |
1364018f | 708 | CHREC_RIGHT (chrec)); |
48e1416a | 709 | |
3bbbcdff | 710 | else if (flow_loop_nested_p (chloop, loop)) |
1364018f | 711 | /* There is no evolution in this loop. */ |
712 | return initial_condition (chrec); | |
48e1416a | 713 | |
1364018f | 714 | else |
3bbbcdff | 715 | { |
716 | gcc_assert (flow_loop_nested_p (loop, chloop)); | |
48e1416a | 717 | return hide_evolution_in_other_loops_than_loop (CHREC_LEFT (chrec), |
3bbbcdff | 718 | loop_num); |
719 | } | |
48e1416a | 720 | |
1364018f | 721 | default: |
722 | return chrec; | |
723 | } | |
724 | } | |
725 | ||
9ce81338 | 726 | /* Returns the evolution part of CHREC in LOOP_NUM when RIGHT is |
727 | true, otherwise returns the initial condition in LOOP_NUM. */ | |
1364018f | 728 | |
48e1416a | 729 | static tree |
730 | chrec_component_in_loop_num (tree chrec, | |
9ce81338 | 731 | unsigned loop_num, |
732 | bool right) | |
1364018f | 733 | { |
9ce81338 | 734 | tree component; |
3bbbcdff | 735 | struct loop *loop = get_loop (loop_num), *chloop; |
9ce81338 | 736 | |
1364018f | 737 | if (automatically_generated_chrec_p (chrec)) |
738 | return chrec; | |
48e1416a | 739 | |
1364018f | 740 | switch (TREE_CODE (chrec)) |
741 | { | |
742 | case POLYNOMIAL_CHREC: | |
3bbbcdff | 743 | chloop = get_chrec_loop (chrec); |
744 | ||
745 | if (chloop == loop) | |
1364018f | 746 | { |
9ce81338 | 747 | if (right) |
748 | component = CHREC_RIGHT (chrec); | |
749 | else | |
750 | component = CHREC_LEFT (chrec); | |
751 | ||
1364018f | 752 | if (TREE_CODE (CHREC_LEFT (chrec)) != POLYNOMIAL_CHREC |
753 | || CHREC_VARIABLE (CHREC_LEFT (chrec)) != CHREC_VARIABLE (chrec)) | |
9ce81338 | 754 | return component; |
48e1416a | 755 | |
1364018f | 756 | else |
757 | return build_polynomial_chrec | |
48e1416a | 758 | (loop_num, |
759 | chrec_component_in_loop_num (CHREC_LEFT (chrec), | |
760 | loop_num, | |
761 | right), | |
9ce81338 | 762 | component); |
1364018f | 763 | } |
48e1416a | 764 | |
3bbbcdff | 765 | else if (flow_loop_nested_p (chloop, loop)) |
1364018f | 766 | /* There is no evolution part in this loop. */ |
767 | return NULL_TREE; | |
48e1416a | 768 | |
1364018f | 769 | else |
3bbbcdff | 770 | { |
771 | gcc_assert (flow_loop_nested_p (loop, chloop)); | |
48e1416a | 772 | return chrec_component_in_loop_num (CHREC_LEFT (chrec), |
773 | loop_num, | |
3bbbcdff | 774 | right); |
775 | } | |
48e1416a | 776 | |
9ce81338 | 777 | default: |
778 | if (right) | |
779 | return NULL_TREE; | |
780 | else | |
781 | return chrec; | |
1364018f | 782 | } |
783 | } | |
784 | ||
9ce81338 | 785 | /* Returns the evolution part in LOOP_NUM. Example: the call |
48e1416a | 786 | evolution_part_in_loop_num ({{0, +, 1}_1, +, 2}_1, 1) returns |
9ce81338 | 787 | {1, +, 2}_1 */ |
788 | ||
48e1416a | 789 | tree |
790 | evolution_part_in_loop_num (tree chrec, | |
9ce81338 | 791 | unsigned loop_num) |
792 | { | |
793 | return chrec_component_in_loop_num (chrec, loop_num, true); | |
794 | } | |
795 | ||
796 | /* Returns the initial condition in LOOP_NUM. Example: the call | |
48e1416a | 797 | initial_condition_in_loop_num ({{0, +, 1}_1, +, 2}_2, 2) returns |
9ce81338 | 798 | {0, +, 1}_1 */ |
799 | ||
48e1416a | 800 | tree |
801 | initial_condition_in_loop_num (tree chrec, | |
9ce81338 | 802 | unsigned loop_num) |
803 | { | |
804 | return chrec_component_in_loop_num (chrec, loop_num, false); | |
805 | } | |
806 | ||
1364018f | 807 | /* Set or reset the evolution of CHREC to NEW_EVOL in loop LOOP_NUM. |
808 | This function is essentially used for setting the evolution to | |
809 | chrec_dont_know, for example after having determined that it is | |
810 | impossible to say how many times a loop will execute. */ | |
811 | ||
48e1416a | 812 | tree |
1364018f | 813 | reset_evolution_in_loop (unsigned loop_num, |
48e1416a | 814 | tree chrec, |
1364018f | 815 | tree new_evol) |
816 | { | |
3bbbcdff | 817 | struct loop *loop = get_loop (loop_num); |
818 | ||
0de36bdb | 819 | if (POINTER_TYPE_P (chrec_type (chrec))) |
a845d317 | 820 | gcc_assert (ptrofftype_p (chrec_type (new_evol))); |
0de36bdb | 821 | else |
822 | gcc_assert (chrec_type (chrec) == chrec_type (new_evol)); | |
f84a688a | 823 | |
1364018f | 824 | if (TREE_CODE (chrec) == POLYNOMIAL_CHREC |
3bbbcdff | 825 | && flow_loop_nested_p (loop, get_chrec_loop (chrec))) |
b74b8216 | 826 | { |
827 | tree left = reset_evolution_in_loop (loop_num, CHREC_LEFT (chrec), | |
828 | new_evol); | |
829 | tree right = reset_evolution_in_loop (loop_num, CHREC_RIGHT (chrec), | |
830 | new_evol); | |
831 | return build3 (POLYNOMIAL_CHREC, TREE_TYPE (left), | |
bad12c62 | 832 | CHREC_VAR (chrec), left, right); |
b74b8216 | 833 | } |
834 | ||
1364018f | 835 | while (TREE_CODE (chrec) == POLYNOMIAL_CHREC |
836 | && CHREC_VARIABLE (chrec) == loop_num) | |
837 | chrec = CHREC_LEFT (chrec); | |
48e1416a | 838 | |
1364018f | 839 | return build_polynomial_chrec (loop_num, chrec, new_evol); |
840 | } | |
841 | ||
842 | /* Merges two evolution functions that were found by following two | |
843 | alternate paths of a conditional expression. */ | |
844 | ||
845 | tree | |
48e1416a | 846 | chrec_merge (tree chrec1, |
1364018f | 847 | tree chrec2) |
848 | { | |
849 | if (chrec1 == chrec_dont_know | |
850 | || chrec2 == chrec_dont_know) | |
851 | return chrec_dont_know; | |
852 | ||
48e1416a | 853 | if (chrec1 == chrec_known |
1364018f | 854 | || chrec2 == chrec_known) |
855 | return chrec_known; | |
856 | ||
857 | if (chrec1 == chrec_not_analyzed_yet) | |
858 | return chrec2; | |
859 | if (chrec2 == chrec_not_analyzed_yet) | |
860 | return chrec1; | |
861 | ||
55feb6fa | 862 | if (eq_evolutions_p (chrec1, chrec2)) |
1364018f | 863 | return chrec1; |
864 | ||
865 | return chrec_dont_know; | |
866 | } | |
867 | ||
868 | \f | |
869 | ||
870 | /* Observers. */ | |
871 | ||
872 | /* Helper function for is_multivariate_chrec. */ | |
873 | ||
48e1416a | 874 | static bool |
7ecb5bb2 | 875 | is_multivariate_chrec_rec (const_tree chrec, unsigned int rec_var) |
1364018f | 876 | { |
877 | if (chrec == NULL_TREE) | |
878 | return false; | |
48e1416a | 879 | |
1364018f | 880 | if (TREE_CODE (chrec) == POLYNOMIAL_CHREC) |
881 | { | |
882 | if (CHREC_VARIABLE (chrec) != rec_var) | |
883 | return true; | |
884 | else | |
48e1416a | 885 | return (is_multivariate_chrec_rec (CHREC_LEFT (chrec), rec_var) |
1364018f | 886 | || is_multivariate_chrec_rec (CHREC_RIGHT (chrec), rec_var)); |
887 | } | |
888 | else | |
889 | return false; | |
890 | } | |
891 | ||
892 | /* Determine whether the given chrec is multivariate or not. */ | |
893 | ||
48e1416a | 894 | bool |
7ecb5bb2 | 895 | is_multivariate_chrec (const_tree chrec) |
1364018f | 896 | { |
897 | if (chrec == NULL_TREE) | |
898 | return false; | |
48e1416a | 899 | |
1364018f | 900 | if (TREE_CODE (chrec) == POLYNOMIAL_CHREC) |
48e1416a | 901 | return (is_multivariate_chrec_rec (CHREC_LEFT (chrec), |
1364018f | 902 | CHREC_VARIABLE (chrec)) |
48e1416a | 903 | || is_multivariate_chrec_rec (CHREC_RIGHT (chrec), |
1364018f | 904 | CHREC_VARIABLE (chrec))); |
905 | else | |
906 | return false; | |
907 | } | |
908 | ||
909 | /* Determines whether the chrec contains symbolic names or not. */ | |
910 | ||
48e1416a | 911 | bool |
7ecb5bb2 | 912 | chrec_contains_symbols (const_tree chrec) |
1364018f | 913 | { |
c2f47e15 | 914 | int i, n; |
915 | ||
1364018f | 916 | if (chrec == NULL_TREE) |
917 | return false; | |
48e1416a | 918 | |
1364018f | 919 | if (TREE_CODE (chrec) == SSA_NAME |
920 | || TREE_CODE (chrec) == VAR_DECL | |
921 | || TREE_CODE (chrec) == PARM_DECL | |
922 | || TREE_CODE (chrec) == FUNCTION_DECL | |
923 | || TREE_CODE (chrec) == LABEL_DECL | |
924 | || TREE_CODE (chrec) == RESULT_DECL | |
925 | || TREE_CODE (chrec) == FIELD_DECL) | |
926 | return true; | |
c2f47e15 | 927 | |
928 | n = TREE_OPERAND_LENGTH (chrec); | |
929 | for (i = 0; i < n; i++) | |
930 | if (chrec_contains_symbols (TREE_OPERAND (chrec, i))) | |
931 | return true; | |
932 | return false; | |
1364018f | 933 | } |
934 | ||
935 | /* Determines whether the chrec contains undetermined coefficients. */ | |
936 | ||
48e1416a | 937 | bool |
7ecb5bb2 | 938 | chrec_contains_undetermined (const_tree chrec) |
1364018f | 939 | { |
c2f47e15 | 940 | int i, n; |
941 | ||
c4e91ab3 | 942 | if (chrec == chrec_dont_know) |
1364018f | 943 | return true; |
c2f47e15 | 944 | |
c4e91ab3 | 945 | if (chrec == NULL_TREE) |
946 | return false; | |
947 | ||
c2f47e15 | 948 | n = TREE_OPERAND_LENGTH (chrec); |
949 | for (i = 0; i < n; i++) | |
950 | if (chrec_contains_undetermined (TREE_OPERAND (chrec, i))) | |
951 | return true; | |
952 | return false; | |
1364018f | 953 | } |
954 | ||
a89ef955 | 955 | /* Determines whether the tree EXPR contains chrecs, and increment |
956 | SIZE if it is not a NULL pointer by an estimation of the depth of | |
957 | the tree. */ | |
1364018f | 958 | |
959 | bool | |
7ecb5bb2 | 960 | tree_contains_chrecs (const_tree expr, int *size) |
1364018f | 961 | { |
c2f47e15 | 962 | int i, n; |
963 | ||
1364018f | 964 | if (expr == NULL_TREE) |
965 | return false; | |
a89ef955 | 966 | |
967 | if (size) | |
968 | (*size)++; | |
48e1416a | 969 | |
1364018f | 970 | if (tree_is_chrec (expr)) |
971 | return true; | |
a89ef955 | 972 | |
c2f47e15 | 973 | n = TREE_OPERAND_LENGTH (expr); |
974 | for (i = 0; i < n; i++) | |
975 | if (tree_contains_chrecs (TREE_OPERAND (expr, i), size)) | |
976 | return true; | |
977 | return false; | |
1364018f | 978 | } |
979 | ||
b3786ab3 | 980 | /* Recursive helper function. */ |
981 | ||
982 | static bool | |
983 | evolution_function_is_invariant_rec_p (tree chrec, int loopnum) | |
984 | { | |
985 | if (evolution_function_is_constant_p (chrec)) | |
986 | return true; | |
987 | ||
663608f5 | 988 | if (TREE_CODE (chrec) == SSA_NAME |
989 | && (loopnum == 0 | |
990 | || expr_invariant_in_loop_p (get_loop (loopnum), chrec))) | |
b3786ab3 | 991 | return true; |
992 | ||
87975961 | 993 | if (TREE_CODE (chrec) == POLYNOMIAL_CHREC) |
994 | { | |
995 | if (CHREC_VARIABLE (chrec) == (unsigned) loopnum | |
08754147 | 996 | || flow_loop_nested_p (get_loop (loopnum), |
997 | get_loop (CHREC_VARIABLE (chrec))) | |
87975961 | 998 | || !evolution_function_is_invariant_rec_p (CHREC_RIGHT (chrec), |
999 | loopnum) | |
1000 | || !evolution_function_is_invariant_rec_p (CHREC_LEFT (chrec), | |
1001 | loopnum)) | |
1002 | return false; | |
1003 | return true; | |
1004 | } | |
b3786ab3 | 1005 | |
c2f47e15 | 1006 | switch (TREE_OPERAND_LENGTH (chrec)) |
b3786ab3 | 1007 | { |
1008 | case 2: | |
1009 | if (!evolution_function_is_invariant_rec_p (TREE_OPERAND (chrec, 1), | |
1010 | loopnum)) | |
1011 | return false; | |
48e1416a | 1012 | |
b3786ab3 | 1013 | case 1: |
1014 | if (!evolution_function_is_invariant_rec_p (TREE_OPERAND (chrec, 0), | |
1015 | loopnum)) | |
1016 | return false; | |
1017 | return true; | |
1018 | ||
1019 | default: | |
1020 | return false; | |
1021 | } | |
1022 | ||
1023 | return false; | |
1024 | } | |
1025 | ||
1026 | /* Return true if CHREC is invariant in loop LOOPNUM, false otherwise. */ | |
1027 | ||
1028 | bool | |
1029 | evolution_function_is_invariant_p (tree chrec, int loopnum) | |
1030 | { | |
7a3bf727 | 1031 | return evolution_function_is_invariant_rec_p (chrec, loopnum); |
b3786ab3 | 1032 | } |
1033 | ||
1364018f | 1034 | /* Determine whether the given tree is an affine multivariate |
1035 | evolution. */ | |
1036 | ||
48e1416a | 1037 | bool |
7ecb5bb2 | 1038 | evolution_function_is_affine_multivariate_p (const_tree chrec, int loopnum) |
1364018f | 1039 | { |
1040 | if (chrec == NULL_TREE) | |
1041 | return false; | |
48e1416a | 1042 | |
1364018f | 1043 | switch (TREE_CODE (chrec)) |
1044 | { | |
1045 | case POLYNOMIAL_CHREC: | |
9c77efff | 1046 | if (evolution_function_is_invariant_rec_p (CHREC_LEFT (chrec), loopnum)) |
1364018f | 1047 | { |
9c77efff | 1048 | if (evolution_function_is_invariant_rec_p (CHREC_RIGHT (chrec), loopnum)) |
1364018f | 1049 | return true; |
1050 | else | |
1051 | { | |
1052 | if (TREE_CODE (CHREC_RIGHT (chrec)) == POLYNOMIAL_CHREC | |
48e1416a | 1053 | && CHREC_VARIABLE (CHREC_RIGHT (chrec)) |
1364018f | 1054 | != CHREC_VARIABLE (chrec) |
48e1416a | 1055 | && evolution_function_is_affine_multivariate_p |
9c77efff | 1056 | (CHREC_RIGHT (chrec), loopnum)) |
1364018f | 1057 | return true; |
1058 | else | |
1059 | return false; | |
1060 | } | |
1061 | } | |
1062 | else | |
1063 | { | |
9c77efff | 1064 | if (evolution_function_is_invariant_rec_p (CHREC_RIGHT (chrec), loopnum) |
1364018f | 1065 | && TREE_CODE (CHREC_LEFT (chrec)) == POLYNOMIAL_CHREC |
1066 | && CHREC_VARIABLE (CHREC_LEFT (chrec)) != CHREC_VARIABLE (chrec) | |
48e1416a | 1067 | && evolution_function_is_affine_multivariate_p |
9c77efff | 1068 | (CHREC_LEFT (chrec), loopnum)) |
1364018f | 1069 | return true; |
1070 | else | |
1071 | return false; | |
1072 | } | |
48e1416a | 1073 | |
1364018f | 1074 | default: |
1075 | return false; | |
1076 | } | |
1077 | } | |
1078 | ||
48e1416a | 1079 | /* Determine whether the given tree is a function in zero or one |
1364018f | 1080 | variables. */ |
1081 | ||
1082 | bool | |
7ecb5bb2 | 1083 | evolution_function_is_univariate_p (const_tree chrec) |
1364018f | 1084 | { |
1085 | if (chrec == NULL_TREE) | |
1086 | return true; | |
48e1416a | 1087 | |
1364018f | 1088 | switch (TREE_CODE (chrec)) |
1089 | { | |
1090 | case POLYNOMIAL_CHREC: | |
1091 | switch (TREE_CODE (CHREC_LEFT (chrec))) | |
1092 | { | |
1093 | case POLYNOMIAL_CHREC: | |
1094 | if (CHREC_VARIABLE (chrec) != CHREC_VARIABLE (CHREC_LEFT (chrec))) | |
1095 | return false; | |
1096 | if (!evolution_function_is_univariate_p (CHREC_LEFT (chrec))) | |
1097 | return false; | |
1098 | break; | |
48e1416a | 1099 | |
1364018f | 1100 | default: |
08754147 | 1101 | if (tree_contains_chrecs (CHREC_LEFT (chrec), NULL)) |
1102 | return false; | |
1364018f | 1103 | break; |
1104 | } | |
48e1416a | 1105 | |
1364018f | 1106 | switch (TREE_CODE (CHREC_RIGHT (chrec))) |
1107 | { | |
1108 | case POLYNOMIAL_CHREC: | |
1109 | if (CHREC_VARIABLE (chrec) != CHREC_VARIABLE (CHREC_RIGHT (chrec))) | |
1110 | return false; | |
1111 | if (!evolution_function_is_univariate_p (CHREC_RIGHT (chrec))) | |
1112 | return false; | |
1113 | break; | |
48e1416a | 1114 | |
1364018f | 1115 | default: |
08754147 | 1116 | if (tree_contains_chrecs (CHREC_RIGHT (chrec), NULL)) |
1117 | return false; | |
48e1416a | 1118 | break; |
1364018f | 1119 | } |
48e1416a | 1120 | |
1364018f | 1121 | default: |
1122 | return true; | |
1123 | } | |
1124 | } | |
1125 | ||
bc3c8ad4 | 1126 | /* Returns the number of variables of CHREC. Example: the call |
1127 | nb_vars_in_chrec ({{0, +, 1}_5, +, 2}_6) returns 2. */ | |
1128 | ||
48e1416a | 1129 | unsigned |
bc3c8ad4 | 1130 | nb_vars_in_chrec (tree chrec) |
1131 | { | |
1132 | if (chrec == NULL_TREE) | |
1133 | return 0; | |
1134 | ||
1135 | switch (TREE_CODE (chrec)) | |
1136 | { | |
1137 | case POLYNOMIAL_CHREC: | |
48e1416a | 1138 | return 1 + nb_vars_in_chrec |
bc3c8ad4 | 1139 | (initial_condition_in_loop_num (chrec, CHREC_VARIABLE (chrec))); |
1140 | ||
1141 | default: | |
1142 | return 0; | |
1143 | } | |
1144 | } | |
1145 | ||
75a70cf9 | 1146 | static tree chrec_convert_1 (tree, tree, gimple, bool); |
57e3f39a | 1147 | |
1148 | /* Converts BASE and STEP of affine scev to TYPE. LOOP is the loop whose iv | |
1149 | the scev corresponds to. AT_STMT is the statement at that the scev is | |
1150 | evaluated. USE_OVERFLOW_SEMANTICS is true if this function should assume that | |
1151 | the rules for overflow of the given language apply (e.g., that signed | |
1152 | arithmetics in C does not overflow) -- i.e., to use them to avoid unnecessary | |
1153 | tests, but also to enforce that the result follows them. Returns true if the | |
1154 | conversion succeeded, false otherwise. */ | |
1155 | ||
1156 | bool | |
1157 | convert_affine_scev (struct loop *loop, tree type, | |
75a70cf9 | 1158 | tree *base, tree *step, gimple at_stmt, |
57e3f39a | 1159 | bool use_overflow_semantics) |
1160 | { | |
1161 | tree ct = TREE_TYPE (*step); | |
1162 | bool enforce_overflow_semantics; | |
1163 | bool must_check_src_overflow, must_check_rslt_overflow; | |
1164 | tree new_base, new_step; | |
0de36bdb | 1165 | tree step_type = POINTER_TYPE_P (type) ? sizetype : type; |
57e3f39a | 1166 | |
1167 | /* In general, | |
1168 | (TYPE) (BASE + STEP * i) = (TYPE) BASE + (TYPE -- sign extend) STEP * i, | |
1169 | but we must check some assumptions. | |
48e1416a | 1170 | |
57e3f39a | 1171 | 1) If [BASE, +, STEP] wraps, the equation is not valid when precision |
1172 | of CT is smaller than the precision of TYPE. For example, when we | |
1173 | cast unsigned char [254, +, 1] to unsigned, the values on left side | |
1174 | are 254, 255, 0, 1, ..., but those on the right side are | |
1175 | 254, 255, 256, 257, ... | |
1176 | 2) In case that we must also preserve the fact that signed ivs do not | |
1177 | overflow, we must additionally check that the new iv does not wrap. | |
1178 | For example, unsigned char [125, +, 1] casted to signed char could | |
1179 | become a wrapping variable with values 125, 126, 127, -128, -127, ..., | |
1180 | which would confuse optimizers that assume that this does not | |
1181 | happen. */ | |
1182 | must_check_src_overflow = TYPE_PRECISION (ct) < TYPE_PRECISION (type); | |
1183 | ||
1184 | enforce_overflow_semantics = (use_overflow_semantics | |
1185 | && nowrap_type_p (type)); | |
1186 | if (enforce_overflow_semantics) | |
1187 | { | |
1188 | /* We can avoid checking whether the result overflows in the following | |
1189 | cases: | |
1190 | ||
1191 | -- must_check_src_overflow is true, and the range of TYPE is superset | |
1192 | of the range of CT -- i.e., in all cases except if CT signed and | |
1193 | TYPE unsigned. | |
318a3281 | 1194 | -- both CT and TYPE have the same precision and signedness, and we |
1195 | verify instead that the source does not overflow (this may be | |
1196 | easier than verifying it for the result, as we may use the | |
1197 | information about the semantics of overflow in CT). */ | |
57e3f39a | 1198 | if (must_check_src_overflow) |
1199 | { | |
1200 | if (TYPE_UNSIGNED (type) && !TYPE_UNSIGNED (ct)) | |
1201 | must_check_rslt_overflow = true; | |
1202 | else | |
1203 | must_check_rslt_overflow = false; | |
1204 | } | |
1205 | else if (TYPE_UNSIGNED (ct) == TYPE_UNSIGNED (type) | |
1206 | && TYPE_PRECISION (ct) == TYPE_PRECISION (type)) | |
318a3281 | 1207 | { |
1208 | must_check_rslt_overflow = false; | |
1209 | must_check_src_overflow = true; | |
1210 | } | |
57e3f39a | 1211 | else |
1212 | must_check_rslt_overflow = true; | |
1213 | } | |
1214 | else | |
1215 | must_check_rslt_overflow = false; | |
1216 | ||
1217 | if (must_check_src_overflow | |
1218 | && scev_probably_wraps_p (*base, *step, at_stmt, loop, | |
1219 | use_overflow_semantics)) | |
1220 | return false; | |
1221 | ||
1222 | new_base = chrec_convert_1 (type, *base, at_stmt, | |
1223 | use_overflow_semantics); | |
1224 | /* The step must be sign extended, regardless of the signedness | |
1225 | of CT and TYPE. This only needs to be handled specially when | |
1226 | CT is unsigned -- to avoid e.g. unsigned char [100, +, 255] | |
1227 | (with values 100, 99, 98, ...) from becoming signed or unsigned | |
48e1416a | 1228 | [100, +, 255] with values 100, 355, ...; the sign-extension is |
57e3f39a | 1229 | performed by default when CT is signed. */ |
1230 | new_step = *step; | |
0de36bdb | 1231 | if (TYPE_PRECISION (step_type) > TYPE_PRECISION (ct) && TYPE_UNSIGNED (ct)) |
0c2b2fc8 | 1232 | { |
1233 | tree signed_ct = build_nonstandard_integer_type (TYPE_PRECISION (ct), 0); | |
1234 | new_step = chrec_convert_1 (signed_ct, new_step, at_stmt, | |
1235 | use_overflow_semantics); | |
1236 | } | |
0de36bdb | 1237 | new_step = chrec_convert_1 (step_type, new_step, at_stmt, use_overflow_semantics); |
57e3f39a | 1238 | |
1239 | if (automatically_generated_chrec_p (new_base) | |
1240 | || automatically_generated_chrec_p (new_step)) | |
1241 | return false; | |
1242 | ||
1243 | if (must_check_rslt_overflow | |
1244 | /* Note that in this case we cannot use the fact that signed variables | |
1245 | do not overflow, as this is what we are verifying for the new iv. */ | |
1246 | && scev_probably_wraps_p (new_base, new_step, at_stmt, loop, false)) | |
1247 | return false; | |
1248 | ||
1249 | *base = new_base; | |
1250 | *step = new_step; | |
1251 | return true; | |
1252 | } | |
1364018f | 1253 | \f |
1254 | ||
d3746d81 | 1255 | /* Convert CHREC for the right hand side of a CHREC. |
0de36bdb | 1256 | The increment for a pointer type is always sizetype. */ |
d3746d81 | 1257 | |
48e1416a | 1258 | tree |
75a70cf9 | 1259 | chrec_convert_rhs (tree type, tree chrec, gimple at_stmt) |
0de36bdb | 1260 | { |
1261 | if (POINTER_TYPE_P (type)) | |
d3746d81 | 1262 | type = sizetype; |
1263 | ||
0de36bdb | 1264 | return chrec_convert (type, chrec, at_stmt); |
1265 | } | |
1266 | ||
b3786ab3 | 1267 | /* Convert CHREC to TYPE. When the analyzer knows the context in |
1268 | which the CHREC is built, it sets AT_STMT to the statement that | |
1269 | contains the definition of the analyzed variable, otherwise the | |
1270 | conversion is less accurate: the information is used for | |
1271 | determining a more accurate estimation of the number of iterations. | |
1272 | By default AT_STMT could be safely set to NULL_TREE. | |
1273 | ||
1274 | The following rule is always true: TREE_TYPE (chrec) == | |
1275 | TREE_TYPE (CHREC_LEFT (chrec)) == TREE_TYPE (CHREC_RIGHT (chrec)). | |
1276 | An example of what could happen when adding two chrecs and the type | |
1277 | of the CHREC_RIGHT is different than CHREC_LEFT is: | |
48e1416a | 1278 | |
562c4a0b | 1279 | {(uint) 0, +, (uchar) 10} + |
1280 | {(uint) 0, +, (uchar) 250} | |
48e1416a | 1281 | |
562c4a0b | 1282 | that would produce a wrong result if CHREC_RIGHT is not (uint): |
48e1416a | 1283 | |
562c4a0b | 1284 | {(uint) 0, +, (uchar) 4} |
1285 | ||
1286 | instead of | |
1287 | ||
1288 | {(uint) 0, +, (uint) 260} | |
1289 | */ | |
1364018f | 1290 | |
48e1416a | 1291 | tree |
75a70cf9 | 1292 | chrec_convert (tree type, tree chrec, gimple at_stmt) |
57e3f39a | 1293 | { |
1294 | return chrec_convert_1 (type, chrec, at_stmt, true); | |
1295 | } | |
1296 | ||
1297 | /* Convert CHREC to TYPE. When the analyzer knows the context in | |
1298 | which the CHREC is built, it sets AT_STMT to the statement that | |
1299 | contains the definition of the analyzed variable, otherwise the | |
1300 | conversion is less accurate: the information is used for | |
1301 | determining a more accurate estimation of the number of iterations. | |
1302 | By default AT_STMT could be safely set to NULL_TREE. | |
48e1416a | 1303 | |
57e3f39a | 1304 | USE_OVERFLOW_SEMANTICS is true if this function should assume that |
1305 | the rules for overflow of the given language apply (e.g., that signed | |
1306 | arithmetics in C does not overflow) -- i.e., to use them to avoid unnecessary | |
1307 | tests, but also to enforce that the result follows them. */ | |
1308 | ||
48e1416a | 1309 | static tree |
75a70cf9 | 1310 | chrec_convert_1 (tree type, tree chrec, gimple at_stmt, |
57e3f39a | 1311 | bool use_overflow_semantics) |
1364018f | 1312 | { |
b3786ab3 | 1313 | tree ct, res; |
57e3f39a | 1314 | tree base, step; |
1315 | struct loop *loop; | |
b3786ab3 | 1316 | |
1364018f | 1317 | if (automatically_generated_chrec_p (chrec)) |
1318 | return chrec; | |
48e1416a | 1319 | |
1364018f | 1320 | ct = chrec_type (chrec); |
1321 | if (ct == type) | |
1322 | return chrec; | |
1323 | ||
57e3f39a | 1324 | if (!evolution_function_is_affine_p (chrec)) |
1325 | goto keep_cast; | |
9887dd18 | 1326 | |
17519ba0 | 1327 | loop = get_chrec_loop (chrec); |
57e3f39a | 1328 | base = CHREC_LEFT (chrec); |
1329 | step = CHREC_RIGHT (chrec); | |
b3786ab3 | 1330 | |
57e3f39a | 1331 | if (convert_affine_scev (loop, type, &base, &step, at_stmt, |
1332 | use_overflow_semantics)) | |
1333 | return build_polynomial_chrec (loop->num, base, step); | |
1364018f | 1334 | |
57e3f39a | 1335 | /* If we cannot propagate the cast inside the chrec, just keep the cast. */ |
1336 | keep_cast: | |
b5a4c072 | 1337 | /* Fold will not canonicalize (long)(i - 1) to (long)i - 1 because that |
1338 | may be more expensive. We do want to perform this optimization here | |
1339 | though for canonicalization reasons. */ | |
1340 | if (use_overflow_semantics | |
1341 | && (TREE_CODE (chrec) == PLUS_EXPR | |
1342 | || TREE_CODE (chrec) == MINUS_EXPR) | |
04bdcc76 | 1343 | && TREE_CODE (type) == INTEGER_TYPE |
1344 | && TREE_CODE (ct) == INTEGER_TYPE | |
b5a4c072 | 1345 | && TYPE_PRECISION (type) > TYPE_PRECISION (ct) |
1346 | && TYPE_OVERFLOW_UNDEFINED (ct)) | |
1347 | res = fold_build2 (TREE_CODE (chrec), type, | |
1348 | fold_convert (type, TREE_OPERAND (chrec, 0)), | |
1349 | fold_convert (type, TREE_OPERAND (chrec, 1))); | |
3ef23449 | 1350 | /* Similar perform the trick that (signed char)((int)x + 2) can be |
1351 | narrowed to (signed char)((unsigned char)x + 2). */ | |
1352 | else if (use_overflow_semantics | |
1353 | && TREE_CODE (chrec) == POLYNOMIAL_CHREC | |
1354 | && TREE_CODE (ct) == INTEGER_TYPE | |
1355 | && TREE_CODE (type) == INTEGER_TYPE | |
1356 | && TYPE_OVERFLOW_UNDEFINED (type) | |
1357 | && TYPE_PRECISION (type) < TYPE_PRECISION (ct)) | |
1358 | { | |
1359 | tree utype = unsigned_type_for (type); | |
1360 | res = build_polynomial_chrec (CHREC_VARIABLE (chrec), | |
1361 | fold_convert (utype, | |
1362 | CHREC_LEFT (chrec)), | |
1363 | fold_convert (utype, | |
1364 | CHREC_RIGHT (chrec))); | |
1365 | res = chrec_convert_1 (type, res, at_stmt, use_overflow_semantics); | |
1366 | } | |
b5a4c072 | 1367 | else |
1368 | res = fold_convert (type, chrec); | |
562c4a0b | 1369 | |
b3786ab3 | 1370 | /* Don't propagate overflows. */ |
1371 | if (CONSTANT_CLASS_P (res)) | |
f96bd2bf | 1372 | TREE_OVERFLOW (res) = 0; |
b3786ab3 | 1373 | |
1374 | /* But reject constants that don't fit in their type after conversion. | |
1375 | This can happen if TYPE_MIN_VALUE or TYPE_MAX_VALUE are not the | |
1376 | natural values associated with TYPE_PRECISION and TYPE_UNSIGNED, | |
1377 | and can cause problems later when computing niters of loops. Note | |
1378 | that we don't do the check before converting because we don't want | |
1379 | to reject conversions of negative chrecs to unsigned types. */ | |
1380 | if (TREE_CODE (res) == INTEGER_CST | |
1381 | && TREE_CODE (type) == INTEGER_TYPE | |
1382 | && !int_fits_type_p (res, type)) | |
1383 | res = chrec_dont_know; | |
1384 | ||
1385 | return res; | |
1364018f | 1386 | } |
1387 | ||
88d02c9e | 1388 | /* Convert CHREC to TYPE, without regard to signed overflows. Returns the new |
1389 | chrec if something else than what chrec_convert would do happens, NULL_TREE | |
1390 | otherwise. */ | |
1391 | ||
1392 | tree | |
1393 | chrec_convert_aggressive (tree type, tree chrec) | |
1394 | { | |
0de36bdb | 1395 | tree inner_type, left, right, lc, rc, rtype; |
88d02c9e | 1396 | |
1397 | if (automatically_generated_chrec_p (chrec) | |
1398 | || TREE_CODE (chrec) != POLYNOMIAL_CHREC) | |
1399 | return NULL_TREE; | |
1400 | ||
1401 | inner_type = TREE_TYPE (chrec); | |
1402 | if (TYPE_PRECISION (type) > TYPE_PRECISION (inner_type)) | |
1403 | return NULL_TREE; | |
1404 | ||
0de36bdb | 1405 | rtype = POINTER_TYPE_P (type) ? sizetype : type; |
1406 | ||
88d02c9e | 1407 | left = CHREC_LEFT (chrec); |
1408 | right = CHREC_RIGHT (chrec); | |
1409 | lc = chrec_convert_aggressive (type, left); | |
1410 | if (!lc) | |
75a70cf9 | 1411 | lc = chrec_convert (type, left, NULL); |
0de36bdb | 1412 | rc = chrec_convert_aggressive (rtype, right); |
88d02c9e | 1413 | if (!rc) |
75a70cf9 | 1414 | rc = chrec_convert (rtype, right, NULL); |
48e1416a | 1415 | |
88d02c9e | 1416 | return build_polynomial_chrec (CHREC_VARIABLE (chrec), lc, rc); |
1417 | } | |
1418 | ||
6b421feb | 1419 | /* Returns true when CHREC0 == CHREC1. */ |
1420 | ||
48e1416a | 1421 | bool |
7ecb5bb2 | 1422 | eq_evolutions_p (const_tree chrec0, const_tree chrec1) |
6b421feb | 1423 | { |
1424 | if (chrec0 == NULL_TREE | |
1425 | || chrec1 == NULL_TREE | |
1426 | || TREE_CODE (chrec0) != TREE_CODE (chrec1)) | |
1427 | return false; | |
1428 | ||
1429 | if (chrec0 == chrec1) | |
1430 | return true; | |
1431 | ||
1432 | switch (TREE_CODE (chrec0)) | |
1433 | { | |
1434 | case INTEGER_CST: | |
f84a688a | 1435 | return operand_equal_p (chrec0, chrec1, 0); |
1436 | ||
6b421feb | 1437 | case POLYNOMIAL_CHREC: |
1438 | return (CHREC_VARIABLE (chrec0) == CHREC_VARIABLE (chrec1) | |
1439 | && eq_evolutions_p (CHREC_LEFT (chrec0), CHREC_LEFT (chrec1)) | |
1440 | && eq_evolutions_p (CHREC_RIGHT (chrec0), CHREC_RIGHT (chrec1))); | |
99c68579 | 1441 | |
1442 | case PLUS_EXPR: | |
1443 | case MULT_EXPR: | |
1444 | case MINUS_EXPR: | |
1445 | case POINTER_PLUS_EXPR: | |
1446 | return eq_evolutions_p (TREE_OPERAND (chrec0, 0), | |
1447 | TREE_OPERAND (chrec1, 0)) | |
1448 | && eq_evolutions_p (TREE_OPERAND (chrec0, 1), | |
1449 | TREE_OPERAND (chrec1, 1)); | |
1450 | ||
6b421feb | 1451 | default: |
1452 | return false; | |
48e1416a | 1453 | } |
6b421feb | 1454 | } |
1455 | ||
57e3f39a | 1456 | /* Returns EV_GROWS if CHREC grows (assuming that it does not overflow), |
1457 | EV_DECREASES if it decreases, and EV_UNKNOWN if we cannot determine | |
1458 | which of these cases happens. */ | |
1459 | ||
1460 | enum ev_direction | |
7ecb5bb2 | 1461 | scev_direction (const_tree chrec) |
57e3f39a | 1462 | { |
7ecb5bb2 | 1463 | const_tree step; |
57e3f39a | 1464 | |
1465 | if (!evolution_function_is_affine_p (chrec)) | |
1466 | return EV_DIR_UNKNOWN; | |
1467 | ||
1468 | step = CHREC_RIGHT (chrec); | |
1469 | if (TREE_CODE (step) != INTEGER_CST) | |
1470 | return EV_DIR_UNKNOWN; | |
1471 | ||
1472 | if (tree_int_cst_sign_bit (step)) | |
1473 | return EV_DIR_DECREASES; | |
1474 | else | |
1475 | return EV_DIR_GROWS; | |
1476 | } | |
255b6be7 | 1477 | |
1478 | /* Iterates over all the components of SCEV, and calls CBCK. */ | |
1479 | ||
1480 | void | |
1481 | for_each_scev_op (tree *scev, bool (*cbck) (tree *, void *), void *data) | |
1482 | { | |
1483 | switch (TREE_CODE_LENGTH (TREE_CODE (*scev))) | |
1484 | { | |
1485 | case 3: | |
1486 | for_each_scev_op (&TREE_OPERAND (*scev, 2), cbck, data); | |
1487 | ||
1488 | case 2: | |
1489 | for_each_scev_op (&TREE_OPERAND (*scev, 1), cbck, data); | |
7ed7512f | 1490 | |
255b6be7 | 1491 | case 1: |
1492 | for_each_scev_op (&TREE_OPERAND (*scev, 0), cbck, data); | |
1493 | ||
1494 | default: | |
1495 | cbck (scev, data); | |
1496 | break; | |
1497 | } | |
1498 | } | |
1499 | ||
145bdf6a | 1500 | /* Returns true when the operation can be part of a linear |
1501 | expression. */ | |
1502 | ||
1503 | static inline bool | |
1504 | operator_is_linear (tree scev) | |
1505 | { | |
1506 | switch (TREE_CODE (scev)) | |
1507 | { | |
1508 | case INTEGER_CST: | |
1509 | case POLYNOMIAL_CHREC: | |
1510 | case PLUS_EXPR: | |
1511 | case POINTER_PLUS_EXPR: | |
1512 | case MULT_EXPR: | |
1513 | case MINUS_EXPR: | |
1514 | case NEGATE_EXPR: | |
1515 | case SSA_NAME: | |
1516 | case NON_LVALUE_EXPR: | |
7ed7512f | 1517 | case BIT_NOT_EXPR: |
145bdf6a | 1518 | CASE_CONVERT: |
1519 | return true; | |
1520 | ||
1521 | default: | |
1522 | return false; | |
1523 | } | |
1524 | } | |
1525 | ||
1526 | /* Return true when SCEV is a linear expression. Linear expressions | |
1527 | can contain additions, substractions and multiplications. | |
1528 | Multiplications are restricted to constant scaling: "cst * x". */ | |
1529 | ||
1530 | bool | |
1531 | scev_is_linear_expression (tree scev) | |
1532 | { | |
1533 | if (scev == NULL | |
1534 | || !operator_is_linear (scev)) | |
1535 | return false; | |
1536 | ||
1537 | if (TREE_CODE (scev) == MULT_EXPR) | |
1538 | return !(tree_contains_chrecs (TREE_OPERAND (scev, 0), NULL) | |
1539 | && tree_contains_chrecs (TREE_OPERAND (scev, 1), NULL)); | |
1540 | ||
7ed7512f | 1541 | if (TREE_CODE (scev) == POLYNOMIAL_CHREC |
1542 | && !evolution_function_is_affine_multivariate_p (scev, CHREC_VARIABLE (scev))) | |
1543 | return false; | |
1544 | ||
145bdf6a | 1545 | switch (TREE_CODE_LENGTH (TREE_CODE (scev))) |
1546 | { | |
1547 | case 3: | |
1548 | return scev_is_linear_expression (TREE_OPERAND (scev, 0)) | |
1549 | && scev_is_linear_expression (TREE_OPERAND (scev, 1)) | |
1550 | && scev_is_linear_expression (TREE_OPERAND (scev, 2)); | |
1551 | ||
1552 | case 2: | |
1553 | return scev_is_linear_expression (TREE_OPERAND (scev, 0)) | |
1554 | && scev_is_linear_expression (TREE_OPERAND (scev, 1)); | |
7ed7512f | 1555 | |
145bdf6a | 1556 | case 1: |
1557 | return scev_is_linear_expression (TREE_OPERAND (scev, 0)); | |
1558 | ||
1559 | case 0: | |
1560 | return true; | |
1561 | ||
1562 | default: | |
1563 | return false; | |
1564 | } | |
1565 | } | |
e44bcf83 | 1566 | |
1567 | /* Determines whether the expression CHREC contains only interger consts | |
1568 | in the right parts. */ | |
1569 | ||
1570 | bool | |
1571 | evolution_function_right_is_integer_cst (const_tree chrec) | |
1572 | { | |
1573 | if (chrec == NULL_TREE) | |
1574 | return false; | |
1575 | ||
1576 | switch (TREE_CODE (chrec)) | |
1577 | { | |
1578 | case INTEGER_CST: | |
1579 | return true; | |
1580 | ||
1581 | case POLYNOMIAL_CHREC: | |
c4ccbe87 | 1582 | return TREE_CODE (CHREC_RIGHT (chrec)) == INTEGER_CST |
1583 | && (TREE_CODE (CHREC_LEFT (chrec)) != POLYNOMIAL_CHREC | |
1584 | || evolution_function_right_is_integer_cst (CHREC_LEFT (chrec))); | |
e44bcf83 | 1585 | |
c4ccbe87 | 1586 | CASE_CONVERT: |
1587 | return evolution_function_right_is_integer_cst (TREE_OPERAND (chrec, 0)); | |
e44bcf83 | 1588 | |
1589 | default: | |
1590 | return false; | |
1591 | } | |
1592 | } |