1 /* Loop optimizations over tree-ssa.
2 Copyright (C) 2003-2020 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by the
8 Free Software Foundation; either version 3, or (at your option) any
11 GCC is distributed in the hope that it will be useful, but WITHOUT
12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
22 #include "coretypes.h"
26 #include "tree-pass.h"
29 #include "fold-const.h"
30 #include "gimple-iterator.h"
31 #include "tree-ssa-loop-ivopts.h"
32 #include "tree-ssa-loop-manip.h"
33 #include "tree-ssa-loop-niter.h"
34 #include "tree-ssa-loop.h"
36 #include "tree-inline.h"
37 #include "tree-scalar-evolution.h"
38 #include "tree-vectorizer.h"
39 #include "omp-general.h"
40 #include "diagnostic-core.h"
41 #include "stringpool.h"
45 /* A pass making sure loops are fixed up. */
49 const pass_data pass_data_fix_loops
=
51 GIMPLE_PASS
, /* type */
52 "fix_loops", /* name */
53 OPTGROUP_LOOP
, /* optinfo_flags */
54 TV_TREE_LOOP
, /* tv_id */
55 PROP_cfg
, /* properties_required */
56 0, /* properties_provided */
57 0, /* properties_destroyed */
58 0, /* todo_flags_start */
59 0, /* todo_flags_finish */
62 class pass_fix_loops
: public gimple_opt_pass
65 pass_fix_loops (gcc::context
*ctxt
)
66 : gimple_opt_pass (pass_data_fix_loops
, ctxt
)
69 /* opt_pass methods: */
70 virtual bool gate (function
*) { return flag_tree_loop_optimize
; }
72 virtual unsigned int execute (function
*fn
);
73 }; // class pass_fix_loops
76 pass_fix_loops::execute (function
*)
78 if (loops_state_satisfies_p (LOOPS_NEED_FIXUP
))
80 calculate_dominance_info (CDI_DOMINATORS
);
81 fix_loop_structure (NULL
);
89 make_pass_fix_loops (gcc::context
*ctxt
)
91 return new pass_fix_loops (ctxt
);
95 /* Gate for loop pass group. The group is controlled by -ftree-loop-optimize
96 but we also avoid running it when the IL doesn't contain any loop. */
99 gate_loop (function
*fn
)
101 if (!flag_tree_loop_optimize
)
104 /* For -fdump-passes which runs before loop discovery print the
105 state of -ftree-loop-optimize. */
106 if (!loops_for_fn (fn
))
109 return number_of_loops (fn
) > 1;
112 /* The loop superpass. */
116 const pass_data pass_data_tree_loop
=
118 GIMPLE_PASS
, /* type */
120 OPTGROUP_LOOP
, /* optinfo_flags */
121 TV_TREE_LOOP
, /* tv_id */
122 PROP_cfg
, /* properties_required */
123 0, /* properties_provided */
124 0, /* properties_destroyed */
125 0, /* todo_flags_start */
126 0, /* todo_flags_finish */
129 class pass_tree_loop
: public gimple_opt_pass
132 pass_tree_loop (gcc::context
*ctxt
)
133 : gimple_opt_pass (pass_data_tree_loop
, ctxt
)
136 /* opt_pass methods: */
137 virtual bool gate (function
*fn
) { return gate_loop (fn
); }
139 }; // class pass_tree_loop
144 make_pass_tree_loop (gcc::context
*ctxt
)
146 return new pass_tree_loop (ctxt
);
149 /* Gate for oacc kernels pass group. */
152 gate_oacc_kernels (function
*fn
)
157 if (!lookup_attribute ("oacc kernels", DECL_ATTRIBUTES (fn
->decl
)))
161 FOR_EACH_LOOP (loop
, 0)
162 if (loop
->in_oacc_kernels_region
)
168 /* The oacc kernels superpass. */
172 const pass_data pass_data_oacc_kernels
=
174 GIMPLE_PASS
, /* type */
175 "oacc_kernels", /* name */
176 OPTGROUP_LOOP
, /* optinfo_flags */
177 TV_TREE_LOOP
, /* tv_id */
178 PROP_cfg
, /* properties_required */
179 0, /* properties_provided */
180 0, /* properties_destroyed */
181 0, /* todo_flags_start */
182 0, /* todo_flags_finish */
185 class pass_oacc_kernels
: public gimple_opt_pass
188 pass_oacc_kernels (gcc::context
*ctxt
)
189 : gimple_opt_pass (pass_data_oacc_kernels
, ctxt
)
192 /* opt_pass methods: */
193 virtual bool gate (function
*fn
) { return gate_oacc_kernels (fn
); }
195 }; // class pass_oacc_kernels
200 make_pass_oacc_kernels (gcc::context
*ctxt
)
202 return new pass_oacc_kernels (ctxt
);
205 /* The ipa oacc superpass. */
209 const pass_data pass_data_ipa_oacc
=
211 SIMPLE_IPA_PASS
, /* type */
212 "ipa_oacc", /* name */
213 OPTGROUP_LOOP
, /* optinfo_flags */
214 TV_TREE_LOOP
, /* tv_id */
215 PROP_cfg
, /* properties_required */
216 0, /* properties_provided */
217 0, /* properties_destroyed */
218 0, /* todo_flags_start */
219 0, /* todo_flags_finish */
222 class pass_ipa_oacc
: public simple_ipa_opt_pass
225 pass_ipa_oacc (gcc::context
*ctxt
)
226 : simple_ipa_opt_pass (pass_data_ipa_oacc
, ctxt
)
229 /* opt_pass methods: */
230 virtual bool gate (function
*)
234 /* Don't bother doing anything if the program has errors. */
238 }; // class pass_ipa_oacc
242 simple_ipa_opt_pass
*
243 make_pass_ipa_oacc (gcc::context
*ctxt
)
245 return new pass_ipa_oacc (ctxt
);
248 /* The ipa oacc kernels pass. */
252 const pass_data pass_data_ipa_oacc_kernels
=
254 SIMPLE_IPA_PASS
, /* type */
255 "ipa_oacc_kernels", /* name */
256 OPTGROUP_LOOP
, /* optinfo_flags */
257 TV_TREE_LOOP
, /* tv_id */
258 PROP_cfg
, /* properties_required */
259 0, /* properties_provided */
260 0, /* properties_destroyed */
261 0, /* todo_flags_start */
262 0, /* todo_flags_finish */
265 class pass_ipa_oacc_kernels
: public simple_ipa_opt_pass
268 pass_ipa_oacc_kernels (gcc::context
*ctxt
)
269 : simple_ipa_opt_pass (pass_data_ipa_oacc_kernels
, ctxt
)
272 }; // class pass_ipa_oacc_kernels
276 simple_ipa_opt_pass
*
277 make_pass_ipa_oacc_kernels (gcc::context
*ctxt
)
279 return new pass_ipa_oacc_kernels (ctxt
);
282 /* The no-loop superpass. */
286 const pass_data pass_data_tree_no_loop
=
288 GIMPLE_PASS
, /* type */
289 "no_loop", /* name */
290 OPTGROUP_NONE
, /* optinfo_flags */
291 TV_TREE_NOLOOP
, /* tv_id */
292 PROP_cfg
, /* properties_required */
293 0, /* properties_provided */
294 0, /* properties_destroyed */
295 0, /* todo_flags_start */
296 0, /* todo_flags_finish */
299 class pass_tree_no_loop
: public gimple_opt_pass
302 pass_tree_no_loop (gcc::context
*ctxt
)
303 : gimple_opt_pass (pass_data_tree_no_loop
, ctxt
)
306 /* opt_pass methods: */
307 virtual bool gate (function
*fn
) { return !gate_loop (fn
); }
309 }; // class pass_tree_no_loop
314 make_pass_tree_no_loop (gcc::context
*ctxt
)
316 return new pass_tree_no_loop (ctxt
);
320 /* Loop optimizer initialization. */
324 const pass_data pass_data_tree_loop_init
=
326 GIMPLE_PASS
, /* type */
327 "loopinit", /* name */
328 OPTGROUP_LOOP
, /* optinfo_flags */
330 PROP_cfg
, /* properties_required */
331 0, /* properties_provided */
332 0, /* properties_destroyed */
333 TODO_update_address_taken
, /* todo_flags_start */
334 0, /* todo_flags_finish */
337 class pass_tree_loop_init
: public gimple_opt_pass
340 pass_tree_loop_init (gcc::context
*ctxt
)
341 : gimple_opt_pass (pass_data_tree_loop_init
, ctxt
)
344 /* opt_pass methods: */
345 virtual unsigned int execute (function
*);
347 }; // class pass_tree_loop_init
350 pass_tree_loop_init::execute (function
*fun ATTRIBUTE_UNUSED
)
352 /* When processing a loop in the loop pipeline, we should be able to assert
354 (loops_state_satisfies_p (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS
356 && scev_initialized_p ())
358 loop_optimizer_init (LOOPS_NORMAL
359 | LOOPS_HAVE_RECORDED_EXITS
);
360 rewrite_into_loop_closed_ssa (NULL
, TODO_update_ssa
);
369 make_pass_tree_loop_init (gcc::context
*ctxt
)
371 return new pass_tree_loop_init (ctxt
);
374 /* Loop autovectorization. */
378 const pass_data pass_data_vectorize
=
380 GIMPLE_PASS
, /* type */
382 OPTGROUP_LOOP
| OPTGROUP_VEC
, /* optinfo_flags */
383 TV_TREE_VECTORIZATION
, /* tv_id */
384 ( PROP_cfg
| PROP_ssa
), /* properties_required */
385 0, /* properties_provided */
386 0, /* properties_destroyed */
387 0, /* todo_flags_start */
388 0, /* todo_flags_finish */
391 class pass_vectorize
: public gimple_opt_pass
394 pass_vectorize (gcc::context
*ctxt
)
395 : gimple_opt_pass (pass_data_vectorize
, ctxt
)
398 /* opt_pass methods: */
399 virtual bool gate (function
*fun
)
401 return flag_tree_loop_vectorize
|| fun
->has_force_vectorize_loops
;
404 virtual unsigned int execute (function
*);
406 }; // class pass_vectorize
409 pass_vectorize::execute (function
*fun
)
411 if (number_of_loops (fun
) <= 1)
414 return vectorize_loops ();
420 make_pass_vectorize (gcc::context
*ctxt
)
422 return new pass_vectorize (ctxt
);
425 /* Propagation of constants using scev. */
429 const pass_data pass_data_scev_cprop
=
431 GIMPLE_PASS
, /* type */
433 OPTGROUP_LOOP
, /* optinfo_flags */
434 TV_SCEV_CONST
, /* tv_id */
435 ( PROP_cfg
| PROP_ssa
), /* properties_required */
436 0, /* properties_provided */
437 0, /* properties_destroyed */
438 0, /* todo_flags_start */
439 0, /* todo_flags_finish */
442 class pass_scev_cprop
: public gimple_opt_pass
445 pass_scev_cprop (gcc::context
*ctxt
)
446 : gimple_opt_pass (pass_data_scev_cprop
, ctxt
)
449 /* opt_pass methods: */
450 virtual bool gate (function
*) { return flag_tree_scev_cprop
; }
451 virtual unsigned int execute (function
*);
453 }; // class pass_scev_cprop
456 pass_scev_cprop::execute (function
*)
461 /* Perform final value replacement in loops, in case the replacement
462 expressions are cheap. */
463 FOR_EACH_LOOP (loop
, LI_FROM_INNERMOST
)
464 any
|= final_value_replacement_loop (loop
);
466 return any
? TODO_cleanup_cfg
| TODO_update_ssa_only_virtuals
: 0;
472 make_pass_scev_cprop (gcc::context
*ctxt
)
474 return new pass_scev_cprop (ctxt
);
477 /* Induction variable optimizations. */
481 const pass_data pass_data_iv_optimize
=
483 GIMPLE_PASS
, /* type */
485 OPTGROUP_LOOP
, /* optinfo_flags */
486 TV_TREE_LOOP_IVOPTS
, /* tv_id */
487 ( PROP_cfg
| PROP_ssa
), /* properties_required */
488 0, /* properties_provided */
489 0, /* properties_destroyed */
490 0, /* todo_flags_start */
491 TODO_update_ssa
, /* todo_flags_finish */
494 class pass_iv_optimize
: public gimple_opt_pass
497 pass_iv_optimize (gcc::context
*ctxt
)
498 : gimple_opt_pass (pass_data_iv_optimize
, ctxt
)
501 /* opt_pass methods: */
502 virtual bool gate (function
*) { return flag_ivopts
!= 0; }
503 virtual unsigned int execute (function
*);
505 }; // class pass_iv_optimize
508 pass_iv_optimize::execute (function
*fun
)
510 if (number_of_loops (fun
) <= 1)
513 tree_ssa_iv_optimize ();
520 make_pass_iv_optimize (gcc::context
*ctxt
)
522 return new pass_iv_optimize (ctxt
);
525 /* Loop optimizer finalization. */
528 tree_ssa_loop_done (void)
530 free_numbers_of_iterations_estimates (cfun
);
532 loop_optimizer_finalize ();
538 const pass_data pass_data_tree_loop_done
=
540 GIMPLE_PASS
, /* type */
541 "loopdone", /* name */
542 OPTGROUP_LOOP
, /* optinfo_flags */
544 PROP_cfg
, /* properties_required */
545 0, /* properties_provided */
546 0, /* properties_destroyed */
547 0, /* todo_flags_start */
548 TODO_cleanup_cfg
, /* todo_flags_finish */
551 class pass_tree_loop_done
: public gimple_opt_pass
554 pass_tree_loop_done (gcc::context
*ctxt
)
555 : gimple_opt_pass (pass_data_tree_loop_done
, ctxt
)
558 /* opt_pass methods: */
559 virtual unsigned int execute (function
*) { return tree_ssa_loop_done (); }
561 }; // class pass_tree_loop_done
566 make_pass_tree_loop_done (gcc::context
*ctxt
)
568 return new pass_tree_loop_done (ctxt
);
571 /* Calls CBCK for each index in memory reference ADDR_P. There are two
572 kinds situations handled; in each of these cases, the memory reference
573 and DATA are passed to the callback:
575 Access to an array: ARRAY_{RANGE_}REF (base, index). In this case we also
576 pass the pointer to the index to the callback.
578 Pointer dereference: INDIRECT_REF (addr). In this case we also pass the
579 pointer to addr to the callback.
581 If the callback returns false, the whole search stops and false is returned.
582 Otherwise the function returns true after traversing through the whole
583 reference *ADDR_P. */
586 for_each_index (tree
*addr_p
, bool (*cbck
) (tree
, tree
*, void *), void *data
)
590 for (; ; addr_p
= nxt
)
592 switch (TREE_CODE (*addr_p
))
595 return cbck (*addr_p
, addr_p
, data
);
598 nxt
= &TREE_OPERAND (*addr_p
, 0);
599 return cbck (*addr_p
, nxt
, data
);
602 case VIEW_CONVERT_EXPR
:
605 nxt
= &TREE_OPERAND (*addr_p
, 0);
609 /* If the component has varying offset, it behaves like index
611 idx
= &TREE_OPERAND (*addr_p
, 2);
613 && !cbck (*addr_p
, idx
, data
))
616 nxt
= &TREE_OPERAND (*addr_p
, 0);
620 case ARRAY_RANGE_REF
:
621 nxt
= &TREE_OPERAND (*addr_p
, 0);
622 if (!cbck (*addr_p
, &TREE_OPERAND (*addr_p
, 1), data
))
630 gcc_assert (is_gimple_min_invariant (*addr_p
));
634 idx
= &TMR_BASE (*addr_p
);
636 && !cbck (*addr_p
, idx
, data
))
638 idx
= &TMR_INDEX (*addr_p
);
640 && !cbck (*addr_p
, idx
, data
))
642 idx
= &TMR_INDEX2 (*addr_p
);
644 && !cbck (*addr_p
, idx
, data
))
650 || CONSTANT_CLASS_P (*addr_p
))
658 /* The name and the length of the currently generated variable
660 #define MAX_LSM_NAME_LENGTH 40
661 static char lsm_tmp_name
[MAX_LSM_NAME_LENGTH
+ 1];
662 static int lsm_tmp_name_length
;
664 /* Adds S to lsm_tmp_name. */
667 lsm_tmp_name_add (const char *s
)
669 int l
= strlen (s
) + lsm_tmp_name_length
;
670 if (l
> MAX_LSM_NAME_LENGTH
)
673 strcpy (lsm_tmp_name
+ lsm_tmp_name_length
, s
);
674 lsm_tmp_name_length
= l
;
677 /* Stores the name for temporary variable that replaces REF to
681 gen_lsm_tmp_name (tree ref
)
685 switch (TREE_CODE (ref
))
689 gen_lsm_tmp_name (TREE_OPERAND (ref
, 0));
690 lsm_tmp_name_add ("_");
694 gen_lsm_tmp_name (TREE_OPERAND (ref
, 0));
698 case VIEW_CONVERT_EXPR
:
699 case ARRAY_RANGE_REF
:
700 gen_lsm_tmp_name (TREE_OPERAND (ref
, 0));
704 gen_lsm_tmp_name (TREE_OPERAND (ref
, 0));
705 lsm_tmp_name_add ("_RE");
709 gen_lsm_tmp_name (TREE_OPERAND (ref
, 0));
710 lsm_tmp_name_add ("_IM");
714 gen_lsm_tmp_name (TREE_OPERAND (ref
, 0));
715 lsm_tmp_name_add ("_");
716 name
= get_name (TREE_OPERAND (ref
, 1));
719 lsm_tmp_name_add (name
);
723 gen_lsm_tmp_name (TREE_OPERAND (ref
, 0));
724 lsm_tmp_name_add ("_I");
732 name
= get_name (ref
);
735 lsm_tmp_name_add (name
);
739 lsm_tmp_name_add ("S");
743 lsm_tmp_name_add ("R");
753 /* Determines name for temporary variable that replaces REF.
754 The name is accumulated into the lsm_tmp_name variable.
755 N is added to the name of the temporary. */
758 get_lsm_tmp_name (tree ref
, unsigned n
, const char *suffix
)
762 lsm_tmp_name_length
= 0;
763 gen_lsm_tmp_name (ref
);
764 lsm_tmp_name_add ("_lsm");
769 lsm_tmp_name_add (ns
);
772 lsm_tmp_name_add (suffix
);
776 /* Computes an estimated number of insns in LOOP, weighted by WEIGHTS. */
779 tree_num_loop_insns (class loop
*loop
, eni_weights
*weights
)
781 basic_block
*body
= get_loop_body (loop
);
782 gimple_stmt_iterator gsi
;
783 unsigned size
= 0, i
;
785 for (i
= 0; i
< loop
->num_nodes
; i
++)
786 for (gsi
= gsi_start_bb (body
[i
]); !gsi_end_p (gsi
); gsi_next (&gsi
))
787 size
+= estimate_num_insns (gsi_stmt (gsi
), weights
);