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3d436d2a | 1 | /* Natural loop functions |
cbe34bb5 | 2 | Copyright (C) 1987-2017 Free Software Foundation, Inc. |
3d436d2a ZD |
3 | |
4 | This file is part of GCC. | |
5 | ||
6 | GCC is free software; you can redistribute it and/or modify it under | |
7 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 8 | Software Foundation; either version 3, or (at your option) any later |
3d436d2a ZD |
9 | version. |
10 | ||
11 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
12 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 | for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
3d436d2a | 19 | |
59587b18 JQ |
20 | #ifndef GCC_CFGLOOP_H |
21 | #define GCC_CFGLOOP_H | |
22 | ||
893479de | 23 | #include "cfgloopmanip.h" |
7a8cba34 | 24 | |
3d436d2a ZD |
25 | /* Structure to hold decision about unrolling/peeling. */ |
26 | enum lpt_dec | |
27 | { | |
28 | LPT_NONE, | |
3d436d2a ZD |
29 | LPT_UNROLL_CONSTANT, |
30 | LPT_UNROLL_RUNTIME, | |
31 | LPT_UNROLL_STUPID | |
32 | }; | |
33 | ||
d1b38208 | 34 | struct GTY (()) lpt_decision { |
3d436d2a ZD |
35 | enum lpt_dec decision; |
36 | unsigned times; | |
37 | }; | |
38 | ||
1c1ad7bb SB |
39 | /* The type of extend applied to an IV. */ |
40 | enum iv_extend_code | |
41 | { | |
42 | IV_SIGN_EXTEND, | |
43 | IV_ZERO_EXTEND, | |
44 | IV_UNKNOWN_EXTEND | |
45 | }; | |
46 | ||
86df10e3 SP |
47 | /* The structure describing a bound on number of iterations of a loop. */ |
48 | ||
d1b38208 | 49 | struct GTY ((chain_next ("%h.next"))) nb_iter_bound { |
946e1bc7 | 50 | /* The statement STMT is executed at most ... */ |
355fe088 | 51 | gimple *stmt; |
946e1bc7 ZD |
52 | |
53 | /* ... BOUND + 1 times (BOUND must be an unsigned constant). | |
54 | The + 1 is added for the following reasons: | |
55 | ||
56 | a) 0 would otherwise be unused, while we would need to care more about | |
57 | overflows (as MAX + 1 is sometimes produced as the estimate on number | |
58 | of executions of STMT). | |
59 | b) it is consistent with the result of number_of_iterations_exit. */ | |
807e902e | 60 | widest_int bound; |
946e1bc7 | 61 | |
b8698a0f | 62 | /* True if the statement will cause the loop to be leaved the (at most) |
946e1bc7 ZD |
63 | BOUND + 1-st time it is executed, that is, all the statements after it |
64 | are executed at most BOUND times. */ | |
65 | bool is_exit; | |
66 | ||
946e1bc7 | 67 | /* The next bound in the list. */ |
86df10e3 | 68 | struct nb_iter_bound *next; |
86df10e3 SP |
69 | }; |
70 | ||
6270df4c ZD |
71 | /* Description of the loop exit. */ |
72 | ||
2a22f99c | 73 | struct GTY ((for_user)) loop_exit { |
6270df4c | 74 | /* The exit edge. */ |
b8244d74 | 75 | edge e; |
6270df4c ZD |
76 | |
77 | /* Previous and next exit in the list of the exits of the loop. */ | |
78 | struct loop_exit *prev; | |
79 | struct loop_exit *next; | |
80 | ||
81 | /* Next element in the list of loops from that E exits. */ | |
82 | struct loop_exit *next_e; | |
83 | }; | |
84 | ||
ca752f39 | 85 | struct loop_exit_hasher : ggc_ptr_hash<loop_exit> |
2a22f99c TS |
86 | { |
87 | typedef edge compare_type; | |
88 | ||
89 | static hashval_t hash (loop_exit *); | |
90 | static bool equal (loop_exit *, edge); | |
91 | static void remove (loop_exit *); | |
92 | }; | |
93 | ||
9ba025a2 | 94 | typedef struct loop *loop_p; |
9ba025a2 | 95 | |
ae50c0cb TN |
96 | /* An integer estimation of the number of iterations. Estimate_state |
97 | describes what is the state of the estimation. */ | |
98 | enum loop_estimation | |
99 | { | |
100 | /* Estimate was not computed yet. */ | |
101 | EST_NOT_COMPUTED, | |
102 | /* Estimate is ready. */ | |
dd366ec3 RB |
103 | EST_AVAILABLE, |
104 | EST_LAST | |
ae50c0cb TN |
105 | }; |
106 | ||
2f07b722 BC |
107 | /* The structure describing non-overflow control induction variable for |
108 | loop's exit edge. */ | |
109 | struct GTY ((chain_next ("%h.next"))) control_iv { | |
110 | tree base; | |
111 | tree step; | |
112 | struct control_iv *next; | |
113 | }; | |
114 | ||
3d436d2a | 115 | /* Structure to hold information for each natural loop. */ |
d1b38208 | 116 | struct GTY ((chain_next ("%h.next"))) loop { |
3d436d2a ZD |
117 | /* Index into loops array. */ |
118 | int num; | |
119 | ||
8f5929e1 JJ |
120 | /* Number of loop insns. */ |
121 | unsigned ninsns; | |
122 | ||
3d436d2a | 123 | /* Basic block of loop header. */ |
b8244d74 | 124 | basic_block header; |
3d436d2a ZD |
125 | |
126 | /* Basic block of loop latch. */ | |
b8244d74 | 127 | basic_block latch; |
3d436d2a | 128 | |
3d436d2a ZD |
129 | /* For loop unrolling/peeling decision. */ |
130 | struct lpt_decision lpt_decision; | |
131 | ||
3d436d2a ZD |
132 | /* Average number of executed insns per iteration. */ |
133 | unsigned av_ninsns; | |
134 | ||
3d436d2a ZD |
135 | /* Number of blocks contained within the loop. */ |
136 | unsigned num_nodes; | |
137 | ||
9ba025a2 | 138 | /* Superloops of the loop, starting with the outermost loop. */ |
9771b263 | 139 | vec<loop_p, va_gc> *superloops; |
3d436d2a ZD |
140 | |
141 | /* The first inner (child) loop or NULL if innermost loop. */ | |
142 | struct loop *inner; | |
143 | ||
144 | /* Link to the next (sibling) loop. */ | |
145 | struct loop *next; | |
146 | ||
3d436d2a | 147 | /* Auxiliary info specific to a pass. */ |
9e2f83a5 | 148 | PTR GTY ((skip (""))) aux; |
3d436d2a | 149 | |
0a74c758 SP |
150 | /* The number of times the latch of the loop is executed. This can be an |
151 | INTEGER_CST, or a symbolic expression representing the number of | |
152 | iterations like "N - 1", or a COND_EXPR containing the runtime | |
153 | conditions under which the number of iterations is non zero. | |
154 | ||
155 | Don't access this field directly: number_of_latch_executions | |
156 | computes and caches the computed information in this field. */ | |
9baba81b SP |
157 | tree nb_iterations; |
158 | ||
b4a9343c ZD |
159 | /* An integer guaranteed to be greater or equal to nb_iterations. Only |
160 | valid if any_upper_bound is true. */ | |
807e902e | 161 | widest_int nb_iterations_upper_bound; |
9bdb685e | 162 | |
105e29c5 JH |
163 | widest_int nb_iterations_likely_upper_bound; |
164 | ||
b4a9343c ZD |
165 | /* An integer giving an estimate on nb_iterations. Unlike |
166 | nb_iterations_upper_bound, there is no guarantee that it is at least | |
167 | nb_iterations. */ | |
807e902e | 168 | widest_int nb_iterations_estimate; |
86df10e3 | 169 | |
8f5929e1 JJ |
170 | bool any_upper_bound; |
171 | bool any_estimate; | |
105e29c5 | 172 | bool any_likely_upper_bound; |
8f5929e1 | 173 | |
448f65db NF |
174 | /* True if the loop can be parallel. */ |
175 | bool can_be_parallel; | |
176 | ||
fbd28bc3 JJ |
177 | /* True if -Waggressive-loop-optimizations warned about this loop |
178 | already. */ | |
179 | bool warned_aggressive_loop_optimizations; | |
180 | ||
8f5929e1 JJ |
181 | /* An integer estimation of the number of iterations. Estimate_state |
182 | describes what is the state of the estimation. */ | |
183 | enum loop_estimation estimate_state; | |
184 | ||
74bf76ed JJ |
185 | /* If > 0, an integer, where the user asserted that for any |
186 | I in [ 0, nb_iterations ) and for any J in | |
187 | [ I, min ( I + safelen, nb_iterations ) ), the Ith and Jth iterations | |
188 | of the loop can be safely evaluated concurrently. */ | |
189 | int safelen; | |
190 | ||
18767ebc BC |
191 | /* Constraints are generally set by consumers and affect certain |
192 | semantics of niter analyzer APIs. Currently the APIs affected are | |
193 | number_of_iterations_exit* functions and their callers. One typical | |
194 | use case of constraints is to vectorize possibly infinite loop: | |
195 | ||
196 | 1) Compute niter->assumptions by calling niter analyzer API and | |
197 | record it as possible condition for loop versioning. | |
198 | 2) Clear buffered result of niter/scev analyzer. | |
199 | 3) Set constraint LOOP_C_FINITE assuming the loop is finite. | |
200 | 4) Analyze data references. Since data reference analysis depends | |
201 | on niter/scev analyzer, the point is that niter/scev analysis | |
202 | is done under circumstance of LOOP_C_FINITE constraint. | |
203 | 5) Version the loop with niter->assumptions computed in step 1). | |
204 | 6) Vectorize the versioned loop in which niter->assumptions is | |
205 | checked to be true. | |
206 | 7) Update constraints in versioned loops so that niter analyzer | |
207 | in following passes can use it. | |
208 | ||
209 | Note consumers are usually the loop optimizers and it is consumers' | |
210 | responsibility to set/clear constraints correctly. Failing to do | |
211 | that might result in hard to track down bugs in niter/scev consumers. */ | |
212 | unsigned constraints; | |
213 | ||
5ce9450f JJ |
214 | /* True if this loop should never be vectorized. */ |
215 | bool dont_vectorize; | |
216 | ||
718c4601 EB |
217 | /* True if we should try harder to vectorize this loop. */ |
218 | bool force_vectorize; | |
219 | ||
886c388d TV |
220 | /* True if the loop is part of an oacc kernels region. */ |
221 | bool in_oacc_kernels_region; | |
222 | ||
74bf76ed JJ |
223 | /* For SIMD loops, this is a unique identifier of the loop, referenced |
224 | by IFN_GOMP_SIMD_VF, IFN_GOMP_SIMD_LANE and IFN_GOMP_SIMD_LAST_LANE | |
225 | builtins. */ | |
226 | tree simduid; | |
227 | ||
e9eb809d ZD |
228 | /* Upper bound on number of iterations of a loop. */ |
229 | struct nb_iter_bound *bounds; | |
82b85a85 | 230 | |
2f07b722 BC |
231 | /* Non-overflow control ivs of a loop. */ |
232 | struct control_iv *control_ivs; | |
233 | ||
6270df4c | 234 | /* Head of the cyclic list of the exits of the loop. */ |
9e2f83a5 | 235 | struct loop_exit *exits; |
ef23e6a2 RB |
236 | |
237 | /* Number of iteration analysis data for RTL. */ | |
238 | struct niter_desc *simple_loop_desc; | |
e4ca2139 | 239 | |
e4ca2139 RB |
240 | /* For sanity checking during loop fixup we record here the former |
241 | loop header for loops marked for removal. Note that this prevents | |
242 | the basic-block from being collected but its index can still be | |
243 | reused. */ | |
244 | basic_block former_header; | |
3d436d2a ZD |
245 | }; |
246 | ||
18767ebc BC |
247 | /* Set if the loop is known to be infinite. */ |
248 | #define LOOP_C_INFINITE (1 << 0) | |
249 | /* Set if the loop is known to be finite without any assumptions. */ | |
250 | #define LOOP_C_FINITE (1 << 1) | |
251 | ||
252 | /* Set C to the LOOP constraint. */ | |
253 | static inline void | |
254 | loop_constraint_set (struct loop *loop, unsigned c) | |
255 | { | |
256 | loop->constraints |= c; | |
257 | } | |
258 | ||
259 | /* Clear C from the LOOP constraint. */ | |
260 | static inline void | |
261 | loop_constraint_clear (struct loop *loop, unsigned c) | |
262 | { | |
263 | loop->constraints &= ~c; | |
264 | } | |
265 | ||
266 | /* Check if C is set in the LOOP constraint. */ | |
267 | static inline bool | |
268 | loop_constraint_set_p (struct loop *loop, unsigned c) | |
269 | { | |
270 | return (loop->constraints & c) == c; | |
271 | } | |
272 | ||
3d436d2a ZD |
273 | /* Flags for state of loop structure. */ |
274 | enum | |
275 | { | |
276 | LOOPS_HAVE_PREHEADERS = 1, | |
277 | LOOPS_HAVE_SIMPLE_LATCHES = 2, | |
82b85a85 | 278 | LOOPS_HAVE_MARKED_IRREDUCIBLE_REGIONS = 4, |
89f8f30f | 279 | LOOPS_HAVE_RECORDED_EXITS = 8, |
c7b852c8 | 280 | LOOPS_MAY_HAVE_MULTIPLE_LATCHES = 16, |
592c303d | 281 | LOOP_CLOSED_SSA = 32, |
e855c69d AB |
282 | LOOPS_NEED_FIXUP = 64, |
283 | LOOPS_HAVE_FALLTHRU_PREHEADERS = 128 | |
3d436d2a ZD |
284 | }; |
285 | ||
d78f3f78 ZD |
286 | #define LOOPS_NORMAL (LOOPS_HAVE_PREHEADERS | LOOPS_HAVE_SIMPLE_LATCHES \ |
287 | | LOOPS_HAVE_MARKED_IRREDUCIBLE_REGIONS) | |
89f8f30f | 288 | #define AVOID_CFG_MODIFICATIONS (LOOPS_MAY_HAVE_MULTIPLE_LATCHES) |
d78f3f78 | 289 | |
3d436d2a | 290 | /* Structure to hold CFG information about natural loops within a function. */ |
d1b38208 | 291 | struct GTY (()) loops { |
0162f155 RG |
292 | /* State of loops. */ |
293 | int state; | |
3d436d2a | 294 | |
42fd6772 | 295 | /* Array of the loops. */ |
9771b263 | 296 | vec<loop_p, va_gc> *larray; |
3d436d2a | 297 | |
6270df4c ZD |
298 | /* Maps edges to the list of their descriptions as loop exits. Edges |
299 | whose sources or destinations have loop_father == NULL (which may | |
300 | happen during the cfg manipulations) should not appear in EXITS. */ | |
2a22f99c | 301 | hash_table<loop_exit_hasher> *GTY(()) exits; |
6270df4c | 302 | |
3d436d2a ZD |
303 | /* Pointer to root of loop hierarchy tree. */ |
304 | struct loop *tree_root; | |
3d436d2a ZD |
305 | }; |
306 | ||
3d436d2a | 307 | /* Loop recognition. */ |
0375167b | 308 | bool bb_loop_header_p (basic_block); |
dd366ec3 | 309 | void init_loops_structure (struct function *, struct loops *, unsigned); |
0375167b | 310 | extern struct loops *flow_loops_find (struct loops *); |
89f8f30f | 311 | extern void disambiguate_loops_with_multiple_latches (void); |
d329e058 | 312 | extern void flow_loops_free (struct loops *); |
d73be268 | 313 | extern void flow_loops_dump (FILE *, |
d329e058 AJ |
314 | void (*)(const struct loop *, FILE *, int), int); |
315 | extern void flow_loop_dump (const struct loop *, FILE *, | |
316 | void (*)(const struct loop *, FILE *, int), int); | |
6270df4c | 317 | struct loop *alloc_loop (void); |
d329e058 | 318 | extern void flow_loop_free (struct loop *); |
2b271002 | 319 | int flow_loop_nodes_find (basic_block, struct loop *); |
8e89b5b5 | 320 | unsigned fix_loop_structure (bitmap changed_bbs); |
2de58650 | 321 | bool mark_irreducible_loops (void); |
61183076 | 322 | void release_recorded_exits (function *); |
6270df4c ZD |
323 | void record_loop_exits (void); |
324 | void rescan_loop_exit (edge, bool, bool); | |
3d436d2a | 325 | |
4d6922ee | 326 | /* Loop data structure manipulation/querying. */ |
d329e058 AJ |
327 | extern void flow_loop_tree_node_add (struct loop *, struct loop *); |
328 | extern void flow_loop_tree_node_remove (struct loop *); | |
d329e058 | 329 | extern bool flow_loop_nested_p (const struct loop *, const struct loop *); |
ed7a4b4b | 330 | extern bool flow_bb_inside_loop_p (const struct loop *, const_basic_block); |
d329e058 | 331 | extern struct loop * find_common_loop (struct loop *, struct loop *); |
a7e5372d | 332 | struct loop *superloop_at_depth (struct loop *, unsigned); |
a79683d5 | 333 | struct eni_weights; |
ed7a4b4b KG |
334 | extern int num_loop_insns (const struct loop *); |
335 | extern int average_num_loop_insns (const struct loop *); | |
689ba89d | 336 | extern unsigned get_loop_level (const struct loop *); |
ed7a4b4b | 337 | extern bool loop_exit_edge_p (const struct loop *, const_edge); |
f4ce375d VK |
338 | extern bool loop_exits_to_bb_p (struct loop *, basic_block); |
339 | extern bool loop_exits_from_bb_p (struct loop *, basic_block); | |
d73be268 | 340 | extern void mark_loop_exit_edges (void); |
e25a6711 | 341 | extern location_t get_loop_location (struct loop *loop); |
3d436d2a ZD |
342 | |
343 | /* Loops & cfg manipulation. */ | |
d329e058 | 344 | extern basic_block *get_loop_body (const struct loop *); |
89f8f30f ZD |
345 | extern unsigned get_loop_body_with_size (const struct loop *, basic_block *, |
346 | unsigned); | |
50654f6c | 347 | extern basic_block *get_loop_body_in_dom_order (const struct loop *); |
40923b20 | 348 | extern basic_block *get_loop_body_in_bfs_order (const struct loop *); |
b8698a0f | 349 | extern basic_block *get_loop_body_in_custom_order (const struct loop *, |
e855c69d AB |
350 | int (*) (const void *, const void *)); |
351 | ||
9771b263 | 352 | extern vec<edge> get_loop_exit_edges (const struct loop *); |
6d96bad2 JH |
353 | extern edge single_exit (const struct loop *); |
354 | extern edge single_likely_exit (struct loop *loop); | |
50654f6c | 355 | extern unsigned num_loop_branches (const struct loop *); |
3d436d2a | 356 | |
d329e058 AJ |
357 | extern edge loop_preheader_edge (const struct loop *); |
358 | extern edge loop_latch_edge (const struct loop *); | |
3d436d2a | 359 | |
d329e058 AJ |
360 | extern void add_bb_to_loop (basic_block, struct loop *); |
361 | extern void remove_bb_from_loops (basic_block); | |
3d436d2a | 362 | |
d73be268 | 363 | extern void cancel_loop_tree (struct loop *); |
42fd6772 | 364 | extern void delete_loop (struct loop *); |
3d436d2a | 365 | |
3d436d2a | 366 | |
d73be268 | 367 | extern void verify_loop_structure (void); |
3d436d2a ZD |
368 | |
369 | /* Loop analysis. */ | |
ed7a4b4b | 370 | extern bool just_once_each_iteration_p (const struct loop *, const_basic_block); |
199b1891 ML |
371 | gcov_type expected_loop_iterations_unbounded (const struct loop *, |
372 | bool *read_profile_p = NULL); | |
97c53806 | 373 | extern unsigned expected_loop_iterations (struct loop *); |
30d2ef86 | 374 | extern rtx doloop_condition_get (rtx_insn *); |
617b465c | 375 | |
08c13199 RB |
376 | void mark_loop_for_removal (loop_p); |
377 | ||
50654f6c ZD |
378 | /* Induction variable analysis. */ |
379 | ||
380 | /* The description of induction variable. The things are a bit complicated | |
381 | due to need to handle subregs and extends. The value of the object described | |
382 | by it can be obtained as follows (all computations are done in extend_mode): | |
383 | ||
384 | Value in i-th iteration is | |
385 | delta + mult * extend_{extend_mode} (subreg_{mode} (base + i * step)). | |
386 | ||
387 | If first_special is true, the value in the first iteration is | |
388 | delta + mult * base | |
c22cacf3 | 389 | |
f822d252 | 390 | If extend = UNKNOWN, first_special must be false, delta 0, mult 1 and value is |
50654f6c ZD |
391 | subreg_{mode} (base + i * step) |
392 | ||
393 | The get_iv_value function can be used to obtain these expressions. | |
394 | ||
395 | ??? Add a third mode field that would specify the mode in that inner | |
396 | computation is done, which would enable it to be different from the | |
397 | outer one? */ | |
398 | ||
399 | struct rtx_iv | |
400 | { | |
401 | /* Its base and step (mode of base and step is supposed to be extend_mode, | |
402 | see the description above). */ | |
403 | rtx base, step; | |
404 | ||
1c1ad7bb SB |
405 | /* The type of extend applied to it (IV_SIGN_EXTEND, IV_ZERO_EXTEND, |
406 | or IV_UNKNOWN_EXTEND). */ | |
407 | enum iv_extend_code extend; | |
50654f6c ZD |
408 | |
409 | /* Operations applied in the extended mode. */ | |
410 | rtx delta, mult; | |
411 | ||
412 | /* The mode it is extended to. */ | |
ef4bddc2 | 413 | machine_mode extend_mode; |
50654f6c ZD |
414 | |
415 | /* The mode the variable iterates in. */ | |
ef4bddc2 | 416 | machine_mode mode; |
50654f6c | 417 | |
50654f6c ZD |
418 | /* Whether the first iteration needs to be handled specially. */ |
419 | unsigned first_special : 1; | |
420 | }; | |
421 | ||
f2dca510 ZD |
422 | /* The description of an exit from the loop and of the number of iterations |
423 | till we take the exit. */ | |
50654f6c | 424 | |
ef23e6a2 | 425 | struct GTY(()) niter_desc |
50654f6c ZD |
426 | { |
427 | /* The edge out of the loop. */ | |
428 | edge out_edge; | |
429 | ||
430 | /* The other edge leading from the condition. */ | |
431 | edge in_edge; | |
432 | ||
433 | /* True if we are able to say anything about number of iterations of the | |
434 | loop. */ | |
435 | bool simple_p; | |
436 | ||
437 | /* True if the loop iterates the constant number of times. */ | |
438 | bool const_iter; | |
439 | ||
440 | /* Number of iterations if constant. */ | |
a9243bfc | 441 | uint64_t niter; |
50654f6c | 442 | |
50654f6c ZD |
443 | /* Assumptions under that the rest of the information is valid. */ |
444 | rtx assumptions; | |
445 | ||
446 | /* Assumptions under that the loop ends before reaching the latch, | |
447 | even if value of niter_expr says otherwise. */ | |
448 | rtx noloop_assumptions; | |
449 | ||
450 | /* Condition under that the loop is infinite. */ | |
451 | rtx infinite; | |
452 | ||
453 | /* Whether the comparison is signed. */ | |
454 | bool signed_p; | |
455 | ||
456 | /* The mode in that niter_expr should be computed. */ | |
ef4bddc2 | 457 | machine_mode mode; |
50654f6c ZD |
458 | |
459 | /* The number of iterations of the loop. */ | |
460 | rtx niter_expr; | |
461 | }; | |
462 | ||
463 | extern void iv_analysis_loop_init (struct loop *); | |
1b20d55a DM |
464 | extern bool iv_analyze (rtx_insn *, rtx, struct rtx_iv *); |
465 | extern bool iv_analyze_result (rtx_insn *, rtx, struct rtx_iv *); | |
ef4bddc2 | 466 | extern bool iv_analyze_expr (rtx_insn *, rtx, machine_mode, |
1b20d55a | 467 | struct rtx_iv *); |
50654f6c | 468 | extern rtx get_iv_value (struct rtx_iv *, rtx); |
1b20d55a | 469 | extern bool biv_p (rtx_insn *, rtx); |
50654f6c | 470 | extern void find_simple_exit (struct loop *, struct niter_desc *); |
50654f6c ZD |
471 | extern void iv_analysis_done (void); |
472 | ||
473 | extern struct niter_desc *get_simple_loop_desc (struct loop *loop); | |
474 | extern void free_simple_loop_desc (struct loop *loop); | |
475 | ||
476 | static inline struct niter_desc * | |
477 | simple_loop_desc (struct loop *loop) | |
478 | { | |
ef23e6a2 | 479 | return loop->simple_loop_desc; |
50654f6c ZD |
480 | } |
481 | ||
42fd6772 ZD |
482 | /* Accessors for the loop structures. */ |
483 | ||
0fc822d0 | 484 | /* Returns the loop with index NUM from FNs loop tree. */ |
42fd6772 ZD |
485 | |
486 | static inline struct loop * | |
0fc822d0 | 487 | get_loop (struct function *fn, unsigned num) |
42fd6772 | 488 | { |
0fc822d0 | 489 | return (*loops_for_fn (fn)->larray)[num]; |
42fd6772 ZD |
490 | } |
491 | ||
9ba025a2 ZD |
492 | /* Returns the number of superloops of LOOP. */ |
493 | ||
494 | static inline unsigned | |
495 | loop_depth (const struct loop *loop) | |
496 | { | |
9771b263 | 497 | return vec_safe_length (loop->superloops); |
9ba025a2 ZD |
498 | } |
499 | ||
500 | /* Returns the immediate superloop of LOOP, or NULL if LOOP is the outermost | |
501 | loop. */ | |
502 | ||
503 | static inline struct loop * | |
504 | loop_outer (const struct loop *loop) | |
505 | { | |
9771b263 | 506 | unsigned n = vec_safe_length (loop->superloops); |
9ba025a2 ZD |
507 | |
508 | if (n == 0) | |
509 | return NULL; | |
510 | ||
9771b263 | 511 | return (*loop->superloops)[n - 1]; |
9ba025a2 ZD |
512 | } |
513 | ||
07643d76 AM |
514 | /* Returns true if LOOP has at least one exit edge. */ |
515 | ||
516 | static inline bool | |
517 | loop_has_exit_edges (const struct loop *loop) | |
518 | { | |
519 | return loop->exits->next->e != NULL; | |
520 | } | |
521 | ||
0fc822d0 | 522 | /* Returns the list of loops in FN. */ |
42fd6772 | 523 | |
0fc822d0 RB |
524 | inline vec<loop_p, va_gc> * |
525 | get_loops (struct function *fn) | |
42fd6772 | 526 | { |
0fc822d0 RB |
527 | struct loops *loops = loops_for_fn (fn); |
528 | if (!loops) | |
42fd6772 ZD |
529 | return NULL; |
530 | ||
0fc822d0 | 531 | return loops->larray; |
42fd6772 ZD |
532 | } |
533 | ||
0fc822d0 | 534 | /* Returns the number of loops in FN (including the removed |
42fd6772 ZD |
535 | ones and the fake loop that forms the root of the loop tree). */ |
536 | ||
537 | static inline unsigned | |
0fc822d0 | 538 | number_of_loops (struct function *fn) |
42fd6772 | 539 | { |
0fc822d0 | 540 | struct loops *loops = loops_for_fn (fn); |
0d0e2af6 | 541 | if (!loops) |
42fd6772 ZD |
542 | return 0; |
543 | ||
0fc822d0 | 544 | return vec_safe_length (loops->larray); |
42fd6772 ZD |
545 | } |
546 | ||
f87000d0 ZD |
547 | /* Returns true if state of the loops satisfies all properties |
548 | described by FLAGS. */ | |
549 | ||
61183076 RB |
550 | static inline bool |
551 | loops_state_satisfies_p (function *fn, unsigned flags) | |
552 | { | |
553 | return (loops_for_fn (fn)->state & flags) == flags; | |
554 | } | |
555 | ||
f87000d0 ZD |
556 | static inline bool |
557 | loops_state_satisfies_p (unsigned flags) | |
558 | { | |
61183076 | 559 | return loops_state_satisfies_p (cfun, flags); |
f87000d0 ZD |
560 | } |
561 | ||
562 | /* Sets FLAGS to the loops state. */ | |
563 | ||
61183076 RB |
564 | static inline void |
565 | loops_state_set (function *fn, unsigned flags) | |
566 | { | |
567 | loops_for_fn (fn)->state |= flags; | |
568 | } | |
569 | ||
f87000d0 ZD |
570 | static inline void |
571 | loops_state_set (unsigned flags) | |
572 | { | |
61183076 | 573 | loops_state_set (cfun, flags); |
f87000d0 ZD |
574 | } |
575 | ||
576 | /* Clears FLAGS from the loops state. */ | |
577 | ||
61183076 RB |
578 | static inline void |
579 | loops_state_clear (function *fn, unsigned flags) | |
580 | { | |
581 | loops_for_fn (fn)->state &= ~flags; | |
582 | } | |
583 | ||
f87000d0 ZD |
584 | static inline void |
585 | loops_state_clear (unsigned flags) | |
586 | { | |
587 | if (!current_loops) | |
588 | return; | |
61183076 | 589 | loops_state_clear (cfun, flags); |
f87000d0 ZD |
590 | } |
591 | ||
a84a49b7 RB |
592 | /* Check loop structure invariants, if internal consistency checks are |
593 | enabled. */ | |
594 | ||
595 | static inline void | |
596 | checking_verify_loop_structure (void) | |
597 | { | |
598 | /* VERIFY_LOOP_STRUCTURE essentially asserts that no loops need fixups. | |
599 | ||
600 | The loop optimizers should never make changes to the CFG which | |
601 | require loop fixups. But the low level CFG manipulation code may | |
602 | set the flag conservatively. | |
603 | ||
604 | Go ahead and clear the flag here. That avoids the assert inside | |
605 | VERIFY_LOOP_STRUCTURE, and if there is an inconsistency in the loop | |
606 | structures VERIFY_LOOP_STRUCTURE will detect it. | |
607 | ||
608 | This also avoid the compile time cost of excessive fixups. */ | |
609 | loops_state_clear (LOOPS_NEED_FIXUP); | |
610 | if (flag_checking) | |
611 | verify_loop_structure (); | |
612 | } | |
613 | ||
42fd6772 ZD |
614 | /* Loop iterators. */ |
615 | ||
616 | /* Flags for loop iteration. */ | |
617 | ||
618 | enum li_flags | |
619 | { | |
677cc14d ZD |
620 | LI_INCLUDE_ROOT = 1, /* Include the fake root of the loop tree. */ |
621 | LI_FROM_INNERMOST = 2, /* Iterate over the loops in the reverse order, | |
622 | starting from innermost ones. */ | |
623 | LI_ONLY_INNERMOST = 4 /* Iterate only over innermost loops. */ | |
42fd6772 ZD |
624 | }; |
625 | ||
626 | /* The iterator for loops. */ | |
627 | ||
f0bd40b1 | 628 | struct loop_iterator |
42fd6772 | 629 | { |
61183076 | 630 | loop_iterator (function *fn, loop_p *loop, unsigned flags); |
f0bd40b1 RB |
631 | ~loop_iterator (); |
632 | ||
633 | inline loop_p next (); | |
634 | ||
61183076 RB |
635 | /* The function we are visiting. */ |
636 | function *fn; | |
637 | ||
677cc14d | 638 | /* The list of loops to visit. */ |
9771b263 | 639 | vec<int> to_visit; |
677cc14d ZD |
640 | |
641 | /* The index of the actual loop. */ | |
642 | unsigned idx; | |
f0bd40b1 | 643 | }; |
42fd6772 | 644 | |
f0bd40b1 RB |
645 | inline loop_p |
646 | loop_iterator::next () | |
42fd6772 | 647 | { |
677cc14d ZD |
648 | int anum; |
649 | ||
f0bd40b1 | 650 | while (this->to_visit.iterate (this->idx, &anum)) |
42fd6772 | 651 | { |
f0bd40b1 | 652 | this->idx++; |
61183076 | 653 | loop_p loop = get_loop (fn, anum); |
f0bd40b1 RB |
654 | if (loop) |
655 | return loop; | |
42fd6772 ZD |
656 | } |
657 | ||
f0bd40b1 | 658 | return NULL; |
42fd6772 ZD |
659 | } |
660 | ||
f0bd40b1 | 661 | inline |
61183076 | 662 | loop_iterator::loop_iterator (function *fn, loop_p *loop, unsigned flags) |
42fd6772 | 663 | { |
677cc14d ZD |
664 | struct loop *aloop; |
665 | unsigned i; | |
666 | int mn; | |
667 | ||
f0bd40b1 | 668 | this->idx = 0; |
61183076 RB |
669 | this->fn = fn; |
670 | if (!loops_for_fn (fn)) | |
42fd6772 | 671 | { |
f0bd40b1 | 672 | this->to_visit.create (0); |
42fd6772 ZD |
673 | *loop = NULL; |
674 | return; | |
675 | } | |
676 | ||
61183076 | 677 | this->to_visit.create (number_of_loops (fn)); |
677cc14d ZD |
678 | mn = (flags & LI_INCLUDE_ROOT) ? 0 : 1; |
679 | ||
680 | if (flags & LI_ONLY_INNERMOST) | |
681 | { | |
61183076 | 682 | for (i = 0; vec_safe_iterate (loops_for_fn (fn)->larray, i, &aloop); i++) |
677cc14d ZD |
683 | if (aloop != NULL |
684 | && aloop->inner == NULL | |
685 | && aloop->num >= mn) | |
f0bd40b1 | 686 | this->to_visit.quick_push (aloop->num); |
677cc14d ZD |
687 | } |
688 | else if (flags & LI_FROM_INNERMOST) | |
42fd6772 | 689 | { |
677cc14d | 690 | /* Push the loops to LI->TO_VISIT in postorder. */ |
61183076 | 691 | for (aloop = loops_for_fn (fn)->tree_root; |
677cc14d ZD |
692 | aloop->inner != NULL; |
693 | aloop = aloop->inner) | |
694 | continue; | |
695 | ||
696 | while (1) | |
697 | { | |
698 | if (aloop->num >= mn) | |
f0bd40b1 | 699 | this->to_visit.quick_push (aloop->num); |
677cc14d ZD |
700 | |
701 | if (aloop->next) | |
702 | { | |
703 | for (aloop = aloop->next; | |
704 | aloop->inner != NULL; | |
705 | aloop = aloop->inner) | |
706 | continue; | |
707 | } | |
9ba025a2 | 708 | else if (!loop_outer (aloop)) |
677cc14d ZD |
709 | break; |
710 | else | |
9ba025a2 | 711 | aloop = loop_outer (aloop); |
677cc14d | 712 | } |
42fd6772 ZD |
713 | } |
714 | else | |
715 | { | |
677cc14d | 716 | /* Push the loops to LI->TO_VISIT in preorder. */ |
61183076 | 717 | aloop = loops_for_fn (fn)->tree_root; |
677cc14d ZD |
718 | while (1) |
719 | { | |
720 | if (aloop->num >= mn) | |
f0bd40b1 | 721 | this->to_visit.quick_push (aloop->num); |
677cc14d ZD |
722 | |
723 | if (aloop->inner != NULL) | |
724 | aloop = aloop->inner; | |
725 | else | |
726 | { | |
727 | while (aloop != NULL && aloop->next == NULL) | |
9ba025a2 | 728 | aloop = loop_outer (aloop); |
677cc14d ZD |
729 | if (aloop == NULL) |
730 | break; | |
731 | aloop = aloop->next; | |
732 | } | |
733 | } | |
42fd6772 | 734 | } |
677cc14d | 735 | |
f0bd40b1 | 736 | *loop = this->next (); |
42fd6772 ZD |
737 | } |
738 | ||
f0bd40b1 RB |
739 | inline |
740 | loop_iterator::~loop_iterator () | |
741 | { | |
742 | this->to_visit.release (); | |
743 | } | |
677cc14d | 744 | |
f0bd40b1 | 745 | #define FOR_EACH_LOOP(LOOP, FLAGS) \ |
61183076 RB |
746 | for (loop_iterator li(cfun, &(LOOP), FLAGS); \ |
747 | (LOOP); \ | |
748 | (LOOP) = li.next ()) | |
749 | ||
750 | #define FOR_EACH_LOOP_FN(FN, LOOP, FLAGS) \ | |
751 | for (loop_iterator li(fn, &(LOOP), FLAGS); \ | |
f0bd40b1 RB |
752 | (LOOP); \ |
753 | (LOOP) = li.next ()) | |
42fd6772 | 754 | |
8b11a64c | 755 | /* The properties of the target. */ |
4391924a RS |
756 | struct target_cfgloop { |
757 | /* Number of available registers. */ | |
758 | unsigned x_target_avail_regs; | |
8b11a64c | 759 | |
4391924a RS |
760 | /* Number of available registers that are call-clobbered. */ |
761 | unsigned x_target_clobbered_regs; | |
762 | ||
763 | /* Number of registers reserved for temporary expressions. */ | |
764 | unsigned x_target_res_regs; | |
765 | ||
766 | /* The cost for register when there still is some reserve, but we are | |
767 | approaching the number of available registers. */ | |
768 | unsigned x_target_reg_cost[2]; | |
769 | ||
770 | /* The cost for register when we need to spill. */ | |
771 | unsigned x_target_spill_cost[2]; | |
772 | }; | |
773 | ||
774 | extern struct target_cfgloop default_target_cfgloop; | |
775 | #if SWITCHABLE_TARGET | |
776 | extern struct target_cfgloop *this_target_cfgloop; | |
777 | #else | |
778 | #define this_target_cfgloop (&default_target_cfgloop) | |
779 | #endif | |
780 | ||
781 | #define target_avail_regs \ | |
782 | (this_target_cfgloop->x_target_avail_regs) | |
783 | #define target_clobbered_regs \ | |
784 | (this_target_cfgloop->x_target_clobbered_regs) | |
785 | #define target_res_regs \ | |
786 | (this_target_cfgloop->x_target_res_regs) | |
787 | #define target_reg_cost \ | |
788 | (this_target_cfgloop->x_target_reg_cost) | |
789 | #define target_spill_cost \ | |
790 | (this_target_cfgloop->x_target_spill_cost) | |
8b11a64c | 791 | |
5e962776 ZD |
792 | /* Register pressure estimation for induction variable optimizations & loop |
793 | invariant motion. */ | |
bec922f0 | 794 | extern unsigned estimate_reg_pressure_cost (unsigned, unsigned, bool, bool); |
5e962776 ZD |
795 | extern void init_set_costs (void); |
796 | ||
617b465c | 797 | /* Loop optimizer initialization. */ |
598ec7bd | 798 | extern void loop_optimizer_init (unsigned); |
61183076 RB |
799 | extern void loop_optimizer_finalize (function *); |
800 | inline void | |
801 | loop_optimizer_finalize () | |
802 | { | |
803 | loop_optimizer_finalize (cfun); | |
804 | } | |
617b465c ZD |
805 | |
806 | /* Optimization passes. */ | |
b17d5d7c ZD |
807 | enum |
808 | { | |
f8934be7 JH |
809 | UAP_UNROLL = 1, /* Enables unrolling of loops if it seems profitable. */ |
810 | UAP_UNROLL_ALL = 2 /* Enables unrolling of all loops. */ | |
b17d5d7c ZD |
811 | }; |
812 | ||
d73be268 ZD |
813 | extern void doloop_optimize_loops (void); |
814 | extern void move_loop_invariants (void); | |
9771b263 | 815 | extern vec<basic_block> get_loop_hot_path (const struct loop *loop); |
59587b18 | 816 | |
a5497b12 VK |
817 | /* Returns the outermost loop of the loop nest that contains LOOP.*/ |
818 | static inline struct loop * | |
819 | loop_outermost (struct loop *loop) | |
820 | { | |
9771b263 | 821 | unsigned n = vec_safe_length (loop->superloops); |
a5497b12 VK |
822 | |
823 | if (n <= 1) | |
824 | return loop; | |
825 | ||
9771b263 | 826 | return (*loop->superloops)[1]; |
a5497b12 VK |
827 | } |
828 | ||
807e902e | 829 | extern void record_niter_bound (struct loop *, const widest_int &, bool, bool); |
1ef88893 | 830 | extern HOST_WIDE_INT get_estimated_loop_iterations_int (struct loop *); |
199b1891 | 831 | extern HOST_WIDE_INT get_max_loop_iterations_int (const struct loop *); |
105e29c5 | 832 | extern HOST_WIDE_INT get_likely_max_loop_iterations_int (struct loop *); |
807e902e | 833 | extern bool get_estimated_loop_iterations (struct loop *loop, widest_int *nit); |
199b1891 | 834 | extern bool get_max_loop_iterations (const struct loop *loop, widest_int *nit); |
105e29c5 | 835 | extern bool get_likely_max_loop_iterations (struct loop *loop, widest_int *nit); |
4484a35a | 836 | extern int bb_loop_depth (const_basic_block); |
a5497b12 | 837 | |
807e902e | 838 | /* Converts VAL to widest_int. */ |
71343877 | 839 | |
807e902e KZ |
840 | static inline widest_int |
841 | gcov_type_to_wide_int (gcov_type val) | |
71343877 | 842 | { |
807e902e | 843 | HOST_WIDE_INT a[2]; |
71343877 | 844 | |
807e902e | 845 | a[0] = (unsigned HOST_WIDE_INT) val; |
71343877 AM |
846 | /* If HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_WIDEST_INT, avoid shifting by |
847 | the size of type. */ | |
848 | val >>= HOST_BITS_PER_WIDE_INT - 1; | |
849 | val >>= 1; | |
807e902e | 850 | a[1] = (unsigned HOST_WIDE_INT) val; |
71343877 | 851 | |
807e902e | 852 | return widest_int::from_array (a, 2); |
71343877 | 853 | } |
59587b18 | 854 | #endif /* GCC_CFGLOOP_H */ |