1 /* Global, SSA-based optimizations using mathematical identities.
2 Copyright (C) 2005-2014 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/>. */
20 /* Currently, the only mini-pass in this file tries to CSE reciprocal
21 operations. These are common in sequences such as this one:
23 modulus = sqrt(x*x + y*y + z*z);
28 that can be optimized to
30 modulus = sqrt(x*x + y*y + z*z);
31 rmodulus = 1.0 / modulus;
36 We do this for loop invariant divisors, and with this pass whenever
37 we notice that a division has the same divisor multiple times.
39 Of course, like in PRE, we don't insert a division if a dominator
40 already has one. However, this cannot be done as an extension of
41 PRE for several reasons.
43 First of all, with some experiments it was found out that the
44 transformation is not always useful if there are only two divisions
45 hy the same divisor. This is probably because modern processors
46 can pipeline the divisions; on older, in-order processors it should
47 still be effective to optimize two divisions by the same number.
48 We make this a param, and it shall be called N in the remainder of
51 Second, if trapping math is active, we have less freedom on where
52 to insert divisions: we can only do so in basic blocks that already
53 contain one. (If divisions don't trap, instead, we can insert
54 divisions elsewhere, which will be in blocks that are common dominators
55 of those that have the division).
57 We really don't want to compute the reciprocal unless a division will
58 be found. To do this, we won't insert the division in a basic block
59 that has less than N divisions *post-dominating* it.
61 The algorithm constructs a subset of the dominator tree, holding the
62 blocks containing the divisions and the common dominators to them,
63 and walk it twice. The first walk is in post-order, and it annotates
64 each block with the number of divisions that post-dominate it: this
65 gives information on where divisions can be inserted profitably.
66 The second walk is in pre-order, and it inserts divisions as explained
67 above, and replaces divisions by multiplications.
69 In the best case, the cost of the pass is O(n_statements). In the
70 worst-case, the cost is due to creating the dominator tree subset,
71 with a cost of O(n_basic_blocks ^ 2); however this can only happen
72 for n_statements / n_basic_blocks statements. So, the amortized cost
73 of creating the dominator tree subset is O(n_basic_blocks) and the
74 worst-case cost of the pass is O(n_statements * n_basic_blocks).
76 More practically, the cost will be small because there are few
77 divisions, and they tend to be in the same basic block, so insert_bb
78 is called very few times.
80 If we did this using domwalk.c, an efficient implementation would have
81 to work on all the variables in a single pass, because we could not
82 work on just a subset of the dominator tree, as we do now, and the
83 cost would also be something like O(n_statements * n_basic_blocks).
84 The data structures would be more complex in order to work on all the
85 variables in a single pass. */
89 #include "coretypes.h"
98 #include "hard-reg-set.h"
100 #include "function.h"
101 #include "dominance.h"
103 #include "basic-block.h"
104 #include "tree-ssa-alias.h"
105 #include "internal-fn.h"
106 #include "gimple-fold.h"
107 #include "gimple-expr.h"
110 #include "gimple-iterator.h"
111 #include "gimplify.h"
112 #include "gimplify-me.h"
113 #include "stor-layout.h"
114 #include "gimple-ssa.h"
115 #include "tree-cfg.h"
116 #include "tree-phinodes.h"
117 #include "ssa-iterators.h"
118 #include "stringpool.h"
119 #include "tree-ssanames.h"
121 #include "tree-dfa.h"
122 #include "tree-ssa.h"
123 #include "tree-pass.h"
124 #include "alloc-pool.h"
126 #include "gimple-pretty-print.h"
127 #include "builtins.h"
129 /* FIXME: RTL headers have to be included here for optabs. */
130 #include "rtl.h" /* Because optabs.h wants enum rtx_code. */
131 #include "expr.h" /* Because optabs.h wants sepops. */
132 #include "insn-codes.h"
135 /* This structure represents one basic block that either computes a
136 division, or is a common dominator for basic block that compute a
139 /* The basic block represented by this structure. */
142 /* If non-NULL, the SSA_NAME holding the definition for a reciprocal
146 /* If non-NULL, the GIMPLE_ASSIGN for a reciprocal computation that
147 was inserted in BB. */
148 gimple recip_def_stmt
;
150 /* Pointer to a list of "struct occurrence"s for blocks dominated
152 struct occurrence
*children
;
154 /* Pointer to the next "struct occurrence"s in the list of blocks
155 sharing a common dominator. */
156 struct occurrence
*next
;
158 /* The number of divisions that are in BB before compute_merit. The
159 number of divisions that are in BB or post-dominate it after
163 /* True if the basic block has a division, false if it is a common
164 dominator for basic blocks that do. If it is false and trapping
165 math is active, BB is not a candidate for inserting a reciprocal. */
166 bool bb_has_division
;
171 /* Number of 1.0/X ops inserted. */
174 /* Number of 1.0/FUNC ops inserted. */
180 /* Number of cexpi calls inserted. */
186 /* Number of hand-written 16-bit nop / bswaps found. */
189 /* Number of hand-written 32-bit nop / bswaps found. */
192 /* Number of hand-written 64-bit nop / bswaps found. */
194 } nop_stats
, bswap_stats
;
198 /* Number of widening multiplication ops inserted. */
199 int widen_mults_inserted
;
201 /* Number of integer multiply-and-accumulate ops inserted. */
204 /* Number of fp fused multiply-add ops inserted. */
208 /* The instance of "struct occurrence" representing the highest
209 interesting block in the dominator tree. */
210 static struct occurrence
*occ_head
;
212 /* Allocation pool for getting instances of "struct occurrence". */
213 static alloc_pool occ_pool
;
217 /* Allocate and return a new struct occurrence for basic block BB, and
218 whose children list is headed by CHILDREN. */
219 static struct occurrence
*
220 occ_new (basic_block bb
, struct occurrence
*children
)
222 struct occurrence
*occ
;
224 bb
->aux
= occ
= (struct occurrence
*) pool_alloc (occ_pool
);
225 memset (occ
, 0, sizeof (struct occurrence
));
228 occ
->children
= children
;
233 /* Insert NEW_OCC into our subset of the dominator tree. P_HEAD points to a
234 list of "struct occurrence"s, one per basic block, having IDOM as
235 their common dominator.
237 We try to insert NEW_OCC as deep as possible in the tree, and we also
238 insert any other block that is a common dominator for BB and one
239 block already in the tree. */
242 insert_bb (struct occurrence
*new_occ
, basic_block idom
,
243 struct occurrence
**p_head
)
245 struct occurrence
*occ
, **p_occ
;
247 for (p_occ
= p_head
; (occ
= *p_occ
) != NULL
; )
249 basic_block bb
= new_occ
->bb
, occ_bb
= occ
->bb
;
250 basic_block dom
= nearest_common_dominator (CDI_DOMINATORS
, occ_bb
, bb
);
253 /* BB dominates OCC_BB. OCC becomes NEW_OCC's child: remove OCC
256 occ
->next
= new_occ
->children
;
257 new_occ
->children
= occ
;
259 /* Try the next block (it may as well be dominated by BB). */
262 else if (dom
== occ_bb
)
264 /* OCC_BB dominates BB. Tail recurse to look deeper. */
265 insert_bb (new_occ
, dom
, &occ
->children
);
269 else if (dom
!= idom
)
271 gcc_assert (!dom
->aux
);
273 /* There is a dominator between IDOM and BB, add it and make
274 two children out of NEW_OCC and OCC. First, remove OCC from
280 /* None of the previous blocks has DOM as a dominator: if we tail
281 recursed, we would reexamine them uselessly. Just switch BB with
282 DOM, and go on looking for blocks dominated by DOM. */
283 new_occ
= occ_new (dom
, new_occ
);
288 /* Nothing special, go on with the next element. */
293 /* No place was found as a child of IDOM. Make BB a sibling of IDOM. */
294 new_occ
->next
= *p_head
;
298 /* Register that we found a division in BB. */
301 register_division_in (basic_block bb
)
303 struct occurrence
*occ
;
305 occ
= (struct occurrence
*) bb
->aux
;
308 occ
= occ_new (bb
, NULL
);
309 insert_bb (occ
, ENTRY_BLOCK_PTR_FOR_FN (cfun
), &occ_head
);
312 occ
->bb_has_division
= true;
313 occ
->num_divisions
++;
317 /* Compute the number of divisions that postdominate each block in OCC and
321 compute_merit (struct occurrence
*occ
)
323 struct occurrence
*occ_child
;
324 basic_block dom
= occ
->bb
;
326 for (occ_child
= occ
->children
; occ_child
; occ_child
= occ_child
->next
)
329 if (occ_child
->children
)
330 compute_merit (occ_child
);
333 bb
= single_noncomplex_succ (dom
);
337 if (dominated_by_p (CDI_POST_DOMINATORS
, bb
, occ_child
->bb
))
338 occ
->num_divisions
+= occ_child
->num_divisions
;
343 /* Return whether USE_STMT is a floating-point division by DEF. */
345 is_division_by (gimple use_stmt
, tree def
)
347 return is_gimple_assign (use_stmt
)
348 && gimple_assign_rhs_code (use_stmt
) == RDIV_EXPR
349 && gimple_assign_rhs2 (use_stmt
) == def
350 /* Do not recognize x / x as valid division, as we are getting
351 confused later by replacing all immediate uses x in such
353 && gimple_assign_rhs1 (use_stmt
) != def
;
356 /* Walk the subset of the dominator tree rooted at OCC, setting the
357 RECIP_DEF field to a definition of 1.0 / DEF that can be used in
358 the given basic block. The field may be left NULL, of course,
359 if it is not possible or profitable to do the optimization.
361 DEF_BSI is an iterator pointing at the statement defining DEF.
362 If RECIP_DEF is set, a dominator already has a computation that can
366 insert_reciprocals (gimple_stmt_iterator
*def_gsi
, struct occurrence
*occ
,
367 tree def
, tree recip_def
, int threshold
)
371 gimple_stmt_iterator gsi
;
372 struct occurrence
*occ_child
;
375 && (occ
->bb_has_division
|| !flag_trapping_math
)
376 && occ
->num_divisions
>= threshold
)
378 /* Make a variable with the replacement and substitute it. */
379 type
= TREE_TYPE (def
);
380 recip_def
= create_tmp_reg (type
, "reciptmp");
381 new_stmt
= gimple_build_assign_with_ops (RDIV_EXPR
, recip_def
,
382 build_one_cst (type
), def
);
384 if (occ
->bb_has_division
)
386 /* Case 1: insert before an existing division. */
387 gsi
= gsi_after_labels (occ
->bb
);
388 while (!gsi_end_p (gsi
) && !is_division_by (gsi_stmt (gsi
), def
))
391 gsi_insert_before (&gsi
, new_stmt
, GSI_SAME_STMT
);
393 else if (def_gsi
&& occ
->bb
== def_gsi
->bb
)
395 /* Case 2: insert right after the definition. Note that this will
396 never happen if the definition statement can throw, because in
397 that case the sole successor of the statement's basic block will
398 dominate all the uses as well. */
399 gsi_insert_after (def_gsi
, new_stmt
, GSI_NEW_STMT
);
403 /* Case 3: insert in a basic block not containing defs/uses. */
404 gsi
= gsi_after_labels (occ
->bb
);
405 gsi_insert_before (&gsi
, new_stmt
, GSI_SAME_STMT
);
408 reciprocal_stats
.rdivs_inserted
++;
410 occ
->recip_def_stmt
= new_stmt
;
413 occ
->recip_def
= recip_def
;
414 for (occ_child
= occ
->children
; occ_child
; occ_child
= occ_child
->next
)
415 insert_reciprocals (def_gsi
, occ_child
, def
, recip_def
, threshold
);
419 /* Replace the division at USE_P with a multiplication by the reciprocal, if
423 replace_reciprocal (use_operand_p use_p
)
425 gimple use_stmt
= USE_STMT (use_p
);
426 basic_block bb
= gimple_bb (use_stmt
);
427 struct occurrence
*occ
= (struct occurrence
*) bb
->aux
;
429 if (optimize_bb_for_speed_p (bb
)
430 && occ
->recip_def
&& use_stmt
!= occ
->recip_def_stmt
)
432 gimple_stmt_iterator gsi
= gsi_for_stmt (use_stmt
);
433 gimple_assign_set_rhs_code (use_stmt
, MULT_EXPR
);
434 SET_USE (use_p
, occ
->recip_def
);
435 fold_stmt_inplace (&gsi
);
436 update_stmt (use_stmt
);
441 /* Free OCC and return one more "struct occurrence" to be freed. */
443 static struct occurrence
*
444 free_bb (struct occurrence
*occ
)
446 struct occurrence
*child
, *next
;
448 /* First get the two pointers hanging off OCC. */
450 child
= occ
->children
;
452 pool_free (occ_pool
, occ
);
454 /* Now ensure that we don't recurse unless it is necessary. */
460 next
= free_bb (next
);
467 /* Look for floating-point divisions among DEF's uses, and try to
468 replace them by multiplications with the reciprocal. Add
469 as many statements computing the reciprocal as needed.
471 DEF must be a GIMPLE register of a floating-point type. */
474 execute_cse_reciprocals_1 (gimple_stmt_iterator
*def_gsi
, tree def
)
477 imm_use_iterator use_iter
;
478 struct occurrence
*occ
;
479 int count
= 0, threshold
;
481 gcc_assert (FLOAT_TYPE_P (TREE_TYPE (def
)) && is_gimple_reg (def
));
483 FOR_EACH_IMM_USE_FAST (use_p
, use_iter
, def
)
485 gimple use_stmt
= USE_STMT (use_p
);
486 if (is_division_by (use_stmt
, def
))
488 register_division_in (gimple_bb (use_stmt
));
493 /* Do the expensive part only if we can hope to optimize something. */
494 threshold
= targetm
.min_divisions_for_recip_mul (TYPE_MODE (TREE_TYPE (def
)));
495 if (count
>= threshold
)
498 for (occ
= occ_head
; occ
; occ
= occ
->next
)
501 insert_reciprocals (def_gsi
, occ
, def
, NULL
, threshold
);
504 FOR_EACH_IMM_USE_STMT (use_stmt
, use_iter
, def
)
506 if (is_division_by (use_stmt
, def
))
508 FOR_EACH_IMM_USE_ON_STMT (use_p
, use_iter
)
509 replace_reciprocal (use_p
);
514 for (occ
= occ_head
; occ
; )
520 /* Go through all the floating-point SSA_NAMEs, and call
521 execute_cse_reciprocals_1 on each of them. */
524 const pass_data pass_data_cse_reciprocals
=
526 GIMPLE_PASS
, /* type */
528 OPTGROUP_NONE
, /* optinfo_flags */
530 PROP_ssa
, /* properties_required */
531 0, /* properties_provided */
532 0, /* properties_destroyed */
533 0, /* todo_flags_start */
534 TODO_update_ssa
, /* todo_flags_finish */
537 class pass_cse_reciprocals
: public gimple_opt_pass
540 pass_cse_reciprocals (gcc::context
*ctxt
)
541 : gimple_opt_pass (pass_data_cse_reciprocals
, ctxt
)
544 /* opt_pass methods: */
545 virtual bool gate (function
*) { return optimize
&& flag_reciprocal_math
; }
546 virtual unsigned int execute (function
*);
548 }; // class pass_cse_reciprocals
551 pass_cse_reciprocals::execute (function
*fun
)
556 occ_pool
= create_alloc_pool ("dominators for recip",
557 sizeof (struct occurrence
),
558 n_basic_blocks_for_fn (fun
) / 3 + 1);
560 memset (&reciprocal_stats
, 0, sizeof (reciprocal_stats
));
561 calculate_dominance_info (CDI_DOMINATORS
);
562 calculate_dominance_info (CDI_POST_DOMINATORS
);
564 #ifdef ENABLE_CHECKING
565 FOR_EACH_BB_FN (bb
, fun
)
566 gcc_assert (!bb
->aux
);
569 for (arg
= DECL_ARGUMENTS (fun
->decl
); arg
; arg
= DECL_CHAIN (arg
))
570 if (FLOAT_TYPE_P (TREE_TYPE (arg
))
571 && is_gimple_reg (arg
))
573 tree name
= ssa_default_def (fun
, arg
);
575 execute_cse_reciprocals_1 (NULL
, name
);
578 FOR_EACH_BB_FN (bb
, fun
)
580 gimple_stmt_iterator gsi
;
584 for (gsi
= gsi_start_phis (bb
); !gsi_end_p (gsi
); gsi_next (&gsi
))
586 phi
= gsi_stmt (gsi
);
587 def
= PHI_RESULT (phi
);
588 if (! virtual_operand_p (def
)
589 && FLOAT_TYPE_P (TREE_TYPE (def
)))
590 execute_cse_reciprocals_1 (NULL
, def
);
593 for (gsi
= gsi_after_labels (bb
); !gsi_end_p (gsi
); gsi_next (&gsi
))
595 gimple stmt
= gsi_stmt (gsi
);
597 if (gimple_has_lhs (stmt
)
598 && (def
= SINGLE_SSA_TREE_OPERAND (stmt
, SSA_OP_DEF
)) != NULL
599 && FLOAT_TYPE_P (TREE_TYPE (def
))
600 && TREE_CODE (def
) == SSA_NAME
)
601 execute_cse_reciprocals_1 (&gsi
, def
);
604 if (optimize_bb_for_size_p (bb
))
607 /* Scan for a/func(b) and convert it to reciprocal a*rfunc(b). */
608 for (gsi
= gsi_after_labels (bb
); !gsi_end_p (gsi
); gsi_next (&gsi
))
610 gimple stmt
= gsi_stmt (gsi
);
613 if (is_gimple_assign (stmt
)
614 && gimple_assign_rhs_code (stmt
) == RDIV_EXPR
)
616 tree arg1
= gimple_assign_rhs2 (stmt
);
619 if (TREE_CODE (arg1
) != SSA_NAME
)
622 stmt1
= SSA_NAME_DEF_STMT (arg1
);
624 if (is_gimple_call (stmt1
)
625 && gimple_call_lhs (stmt1
)
626 && (fndecl
= gimple_call_fndecl (stmt1
))
627 && (DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
628 || DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_MD
))
630 enum built_in_function code
;
635 code
= DECL_FUNCTION_CODE (fndecl
);
636 md_code
= DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_MD
;
638 fndecl
= targetm
.builtin_reciprocal (code
, md_code
, false);
642 /* Check that all uses of the SSA name are divisions,
643 otherwise replacing the defining statement will do
646 FOR_EACH_IMM_USE_FAST (use_p
, ui
, arg1
)
648 gimple stmt2
= USE_STMT (use_p
);
649 if (is_gimple_debug (stmt2
))
651 if (!is_gimple_assign (stmt2
)
652 || gimple_assign_rhs_code (stmt2
) != RDIV_EXPR
653 || gimple_assign_rhs1 (stmt2
) == arg1
654 || gimple_assign_rhs2 (stmt2
) != arg1
)
663 gimple_replace_ssa_lhs (stmt1
, arg1
);
664 gimple_call_set_fndecl (stmt1
, fndecl
);
666 reciprocal_stats
.rfuncs_inserted
++;
668 FOR_EACH_IMM_USE_STMT (stmt
, ui
, arg1
)
670 gimple_stmt_iterator gsi
= gsi_for_stmt (stmt
);
671 gimple_assign_set_rhs_code (stmt
, MULT_EXPR
);
672 fold_stmt_inplace (&gsi
);
680 statistics_counter_event (fun
, "reciprocal divs inserted",
681 reciprocal_stats
.rdivs_inserted
);
682 statistics_counter_event (fun
, "reciprocal functions inserted",
683 reciprocal_stats
.rfuncs_inserted
);
685 free_dominance_info (CDI_DOMINATORS
);
686 free_dominance_info (CDI_POST_DOMINATORS
);
687 free_alloc_pool (occ_pool
);
694 make_pass_cse_reciprocals (gcc::context
*ctxt
)
696 return new pass_cse_reciprocals (ctxt
);
699 /* Records an occurrence at statement USE_STMT in the vector of trees
700 STMTS if it is dominated by *TOP_BB or dominates it or this basic block
701 is not yet initialized. Returns true if the occurrence was pushed on
702 the vector. Adjusts *TOP_BB to be the basic block dominating all
703 statements in the vector. */
706 maybe_record_sincos (vec
<gimple
> *stmts
,
707 basic_block
*top_bb
, gimple use_stmt
)
709 basic_block use_bb
= gimple_bb (use_stmt
);
711 && (*top_bb
== use_bb
712 || dominated_by_p (CDI_DOMINATORS
, use_bb
, *top_bb
)))
713 stmts
->safe_push (use_stmt
);
715 || dominated_by_p (CDI_DOMINATORS
, *top_bb
, use_bb
))
717 stmts
->safe_push (use_stmt
);
726 /* Look for sin, cos and cexpi calls with the same argument NAME and
727 create a single call to cexpi CSEing the result in this case.
728 We first walk over all immediate uses of the argument collecting
729 statements that we can CSE in a vector and in a second pass replace
730 the statement rhs with a REALPART or IMAGPART expression on the
731 result of the cexpi call we insert before the use statement that
732 dominates all other candidates. */
735 execute_cse_sincos_1 (tree name
)
737 gimple_stmt_iterator gsi
;
738 imm_use_iterator use_iter
;
739 tree fndecl
, res
, type
;
740 gimple def_stmt
, use_stmt
, stmt
;
741 int seen_cos
= 0, seen_sin
= 0, seen_cexpi
= 0;
742 vec
<gimple
> stmts
= vNULL
;
743 basic_block top_bb
= NULL
;
745 bool cfg_changed
= false;
747 type
= TREE_TYPE (name
);
748 FOR_EACH_IMM_USE_STMT (use_stmt
, use_iter
, name
)
750 if (gimple_code (use_stmt
) != GIMPLE_CALL
751 || !gimple_call_lhs (use_stmt
)
752 || !(fndecl
= gimple_call_fndecl (use_stmt
))
753 || DECL_BUILT_IN_CLASS (fndecl
) != BUILT_IN_NORMAL
)
756 switch (DECL_FUNCTION_CODE (fndecl
))
758 CASE_FLT_FN (BUILT_IN_COS
):
759 seen_cos
|= maybe_record_sincos (&stmts
, &top_bb
, use_stmt
) ? 1 : 0;
762 CASE_FLT_FN (BUILT_IN_SIN
):
763 seen_sin
|= maybe_record_sincos (&stmts
, &top_bb
, use_stmt
) ? 1 : 0;
766 CASE_FLT_FN (BUILT_IN_CEXPI
):
767 seen_cexpi
|= maybe_record_sincos (&stmts
, &top_bb
, use_stmt
) ? 1 : 0;
774 if (seen_cos
+ seen_sin
+ seen_cexpi
<= 1)
780 /* Simply insert cexpi at the beginning of top_bb but not earlier than
781 the name def statement. */
782 fndecl
= mathfn_built_in (type
, BUILT_IN_CEXPI
);
785 stmt
= gimple_build_call (fndecl
, 1, name
);
786 res
= make_temp_ssa_name (TREE_TYPE (TREE_TYPE (fndecl
)), stmt
, "sincostmp");
787 gimple_call_set_lhs (stmt
, res
);
789 def_stmt
= SSA_NAME_DEF_STMT (name
);
790 if (!SSA_NAME_IS_DEFAULT_DEF (name
)
791 && gimple_code (def_stmt
) != GIMPLE_PHI
792 && gimple_bb (def_stmt
) == top_bb
)
794 gsi
= gsi_for_stmt (def_stmt
);
795 gsi_insert_after (&gsi
, stmt
, GSI_SAME_STMT
);
799 gsi
= gsi_after_labels (top_bb
);
800 gsi_insert_before (&gsi
, stmt
, GSI_SAME_STMT
);
802 sincos_stats
.inserted
++;
804 /* And adjust the recorded old call sites. */
805 for (i
= 0; stmts
.iterate (i
, &use_stmt
); ++i
)
808 fndecl
= gimple_call_fndecl (use_stmt
);
810 switch (DECL_FUNCTION_CODE (fndecl
))
812 CASE_FLT_FN (BUILT_IN_COS
):
813 rhs
= fold_build1 (REALPART_EXPR
, type
, res
);
816 CASE_FLT_FN (BUILT_IN_SIN
):
817 rhs
= fold_build1 (IMAGPART_EXPR
, type
, res
);
820 CASE_FLT_FN (BUILT_IN_CEXPI
):
828 /* Replace call with a copy. */
829 stmt
= gimple_build_assign (gimple_call_lhs (use_stmt
), rhs
);
831 gsi
= gsi_for_stmt (use_stmt
);
832 gsi_replace (&gsi
, stmt
, true);
833 if (gimple_purge_dead_eh_edges (gimple_bb (stmt
)))
842 /* To evaluate powi(x,n), the floating point value x raised to the
843 constant integer exponent n, we use a hybrid algorithm that
844 combines the "window method" with look-up tables. For an
845 introduction to exponentiation algorithms and "addition chains",
846 see section 4.6.3, "Evaluation of Powers" of Donald E. Knuth,
847 "Seminumerical Algorithms", Vol. 2, "The Art of Computer Programming",
848 3rd Edition, 1998, and Daniel M. Gordon, "A Survey of Fast Exponentiation
849 Methods", Journal of Algorithms, Vol. 27, pp. 129-146, 1998. */
851 /* Provide a default value for POWI_MAX_MULTS, the maximum number of
852 multiplications to inline before calling the system library's pow
853 function. powi(x,n) requires at worst 2*bits(n)-2 multiplications,
854 so this default never requires calling pow, powf or powl. */
856 #ifndef POWI_MAX_MULTS
857 #define POWI_MAX_MULTS (2*HOST_BITS_PER_WIDE_INT-2)
860 /* The size of the "optimal power tree" lookup table. All
861 exponents less than this value are simply looked up in the
862 powi_table below. This threshold is also used to size the
863 cache of pseudo registers that hold intermediate results. */
864 #define POWI_TABLE_SIZE 256
866 /* The size, in bits of the window, used in the "window method"
867 exponentiation algorithm. This is equivalent to a radix of
868 (1<<POWI_WINDOW_SIZE) in the corresponding "m-ary method". */
869 #define POWI_WINDOW_SIZE 3
871 /* The following table is an efficient representation of an
872 "optimal power tree". For each value, i, the corresponding
873 value, j, in the table states than an optimal evaluation
874 sequence for calculating pow(x,i) can be found by evaluating
875 pow(x,j)*pow(x,i-j). An optimal power tree for the first
876 100 integers is given in Knuth's "Seminumerical algorithms". */
878 static const unsigned char powi_table
[POWI_TABLE_SIZE
] =
880 0, 1, 1, 2, 2, 3, 3, 4, /* 0 - 7 */
881 4, 6, 5, 6, 6, 10, 7, 9, /* 8 - 15 */
882 8, 16, 9, 16, 10, 12, 11, 13, /* 16 - 23 */
883 12, 17, 13, 18, 14, 24, 15, 26, /* 24 - 31 */
884 16, 17, 17, 19, 18, 33, 19, 26, /* 32 - 39 */
885 20, 25, 21, 40, 22, 27, 23, 44, /* 40 - 47 */
886 24, 32, 25, 34, 26, 29, 27, 44, /* 48 - 55 */
887 28, 31, 29, 34, 30, 60, 31, 36, /* 56 - 63 */
888 32, 64, 33, 34, 34, 46, 35, 37, /* 64 - 71 */
889 36, 65, 37, 50, 38, 48, 39, 69, /* 72 - 79 */
890 40, 49, 41, 43, 42, 51, 43, 58, /* 80 - 87 */
891 44, 64, 45, 47, 46, 59, 47, 76, /* 88 - 95 */
892 48, 65, 49, 66, 50, 67, 51, 66, /* 96 - 103 */
893 52, 70, 53, 74, 54, 104, 55, 74, /* 104 - 111 */
894 56, 64, 57, 69, 58, 78, 59, 68, /* 112 - 119 */
895 60, 61, 61, 80, 62, 75, 63, 68, /* 120 - 127 */
896 64, 65, 65, 128, 66, 129, 67, 90, /* 128 - 135 */
897 68, 73, 69, 131, 70, 94, 71, 88, /* 136 - 143 */
898 72, 128, 73, 98, 74, 132, 75, 121, /* 144 - 151 */
899 76, 102, 77, 124, 78, 132, 79, 106, /* 152 - 159 */
900 80, 97, 81, 160, 82, 99, 83, 134, /* 160 - 167 */
901 84, 86, 85, 95, 86, 160, 87, 100, /* 168 - 175 */
902 88, 113, 89, 98, 90, 107, 91, 122, /* 176 - 183 */
903 92, 111, 93, 102, 94, 126, 95, 150, /* 184 - 191 */
904 96, 128, 97, 130, 98, 133, 99, 195, /* 192 - 199 */
905 100, 128, 101, 123, 102, 164, 103, 138, /* 200 - 207 */
906 104, 145, 105, 146, 106, 109, 107, 149, /* 208 - 215 */
907 108, 200, 109, 146, 110, 170, 111, 157, /* 216 - 223 */
908 112, 128, 113, 130, 114, 182, 115, 132, /* 224 - 231 */
909 116, 200, 117, 132, 118, 158, 119, 206, /* 232 - 239 */
910 120, 240, 121, 162, 122, 147, 123, 152, /* 240 - 247 */
911 124, 166, 125, 214, 126, 138, 127, 153, /* 248 - 255 */
915 /* Return the number of multiplications required to calculate
916 powi(x,n) where n is less than POWI_TABLE_SIZE. This is a
917 subroutine of powi_cost. CACHE is an array indicating
918 which exponents have already been calculated. */
921 powi_lookup_cost (unsigned HOST_WIDE_INT n
, bool *cache
)
923 /* If we've already calculated this exponent, then this evaluation
924 doesn't require any additional multiplications. */
929 return powi_lookup_cost (n
- powi_table
[n
], cache
)
930 + powi_lookup_cost (powi_table
[n
], cache
) + 1;
933 /* Return the number of multiplications required to calculate
934 powi(x,n) for an arbitrary x, given the exponent N. This
935 function needs to be kept in sync with powi_as_mults below. */
938 powi_cost (HOST_WIDE_INT n
)
940 bool cache
[POWI_TABLE_SIZE
];
941 unsigned HOST_WIDE_INT digit
;
942 unsigned HOST_WIDE_INT val
;
948 /* Ignore the reciprocal when calculating the cost. */
949 val
= (n
< 0) ? -n
: n
;
951 /* Initialize the exponent cache. */
952 memset (cache
, 0, POWI_TABLE_SIZE
* sizeof (bool));
957 while (val
>= POWI_TABLE_SIZE
)
961 digit
= val
& ((1 << POWI_WINDOW_SIZE
) - 1);
962 result
+= powi_lookup_cost (digit
, cache
)
963 + POWI_WINDOW_SIZE
+ 1;
964 val
>>= POWI_WINDOW_SIZE
;
973 return result
+ powi_lookup_cost (val
, cache
);
976 /* Recursive subroutine of powi_as_mults. This function takes the
977 array, CACHE, of already calculated exponents and an exponent N and
978 returns a tree that corresponds to CACHE[1]**N, with type TYPE. */
981 powi_as_mults_1 (gimple_stmt_iterator
*gsi
, location_t loc
, tree type
,
982 HOST_WIDE_INT n
, tree
*cache
)
984 tree op0
, op1
, ssa_target
;
985 unsigned HOST_WIDE_INT digit
;
988 if (n
< POWI_TABLE_SIZE
&& cache
[n
])
991 ssa_target
= make_temp_ssa_name (type
, NULL
, "powmult");
993 if (n
< POWI_TABLE_SIZE
)
995 cache
[n
] = ssa_target
;
996 op0
= powi_as_mults_1 (gsi
, loc
, type
, n
- powi_table
[n
], cache
);
997 op1
= powi_as_mults_1 (gsi
, loc
, type
, powi_table
[n
], cache
);
1001 digit
= n
& ((1 << POWI_WINDOW_SIZE
) - 1);
1002 op0
= powi_as_mults_1 (gsi
, loc
, type
, n
- digit
, cache
);
1003 op1
= powi_as_mults_1 (gsi
, loc
, type
, digit
, cache
);
1007 op0
= powi_as_mults_1 (gsi
, loc
, type
, n
>> 1, cache
);
1011 mult_stmt
= gimple_build_assign_with_ops (MULT_EXPR
, ssa_target
, op0
, op1
);
1012 gimple_set_location (mult_stmt
, loc
);
1013 gsi_insert_before (gsi
, mult_stmt
, GSI_SAME_STMT
);
1018 /* Convert ARG0**N to a tree of multiplications of ARG0 with itself.
1019 This function needs to be kept in sync with powi_cost above. */
1022 powi_as_mults (gimple_stmt_iterator
*gsi
, location_t loc
,
1023 tree arg0
, HOST_WIDE_INT n
)
1025 tree cache
[POWI_TABLE_SIZE
], result
, type
= TREE_TYPE (arg0
);
1030 return build_real (type
, dconst1
);
1032 memset (cache
, 0, sizeof (cache
));
1035 result
= powi_as_mults_1 (gsi
, loc
, type
, (n
< 0) ? -n
: n
, cache
);
1039 /* If the original exponent was negative, reciprocate the result. */
1040 target
= make_temp_ssa_name (type
, NULL
, "powmult");
1041 div_stmt
= gimple_build_assign_with_ops (RDIV_EXPR
, target
,
1042 build_real (type
, dconst1
),
1044 gimple_set_location (div_stmt
, loc
);
1045 gsi_insert_before (gsi
, div_stmt
, GSI_SAME_STMT
);
1050 /* ARG0 and N are the two arguments to a powi builtin in GSI with
1051 location info LOC. If the arguments are appropriate, create an
1052 equivalent sequence of statements prior to GSI using an optimal
1053 number of multiplications, and return an expession holding the
1057 gimple_expand_builtin_powi (gimple_stmt_iterator
*gsi
, location_t loc
,
1058 tree arg0
, HOST_WIDE_INT n
)
1060 /* Avoid largest negative number. */
1062 && ((n
>= -1 && n
<= 2)
1063 || (optimize_function_for_speed_p (cfun
)
1064 && powi_cost (n
) <= POWI_MAX_MULTS
)))
1065 return powi_as_mults (gsi
, loc
, arg0
, n
);
1070 /* Build a gimple call statement that calls FN with argument ARG.
1071 Set the lhs of the call statement to a fresh SSA name. Insert the
1072 statement prior to GSI's current position, and return the fresh
1076 build_and_insert_call (gimple_stmt_iterator
*gsi
, location_t loc
,
1082 call_stmt
= gimple_build_call (fn
, 1, arg
);
1083 ssa_target
= make_temp_ssa_name (TREE_TYPE (arg
), NULL
, "powroot");
1084 gimple_set_lhs (call_stmt
, ssa_target
);
1085 gimple_set_location (call_stmt
, loc
);
1086 gsi_insert_before (gsi
, call_stmt
, GSI_SAME_STMT
);
1091 /* Build a gimple binary operation with the given CODE and arguments
1092 ARG0, ARG1, assigning the result to a new SSA name for variable
1093 TARGET. Insert the statement prior to GSI's current position, and
1094 return the fresh SSA name.*/
1097 build_and_insert_binop (gimple_stmt_iterator
*gsi
, location_t loc
,
1098 const char *name
, enum tree_code code
,
1099 tree arg0
, tree arg1
)
1101 tree result
= make_temp_ssa_name (TREE_TYPE (arg0
), NULL
, name
);
1102 gimple stmt
= gimple_build_assign_with_ops (code
, result
, arg0
, arg1
);
1103 gimple_set_location (stmt
, loc
);
1104 gsi_insert_before (gsi
, stmt
, GSI_SAME_STMT
);
1108 /* Build a gimple reference operation with the given CODE and argument
1109 ARG, assigning the result to a new SSA name of TYPE with NAME.
1110 Insert the statement prior to GSI's current position, and return
1111 the fresh SSA name. */
1114 build_and_insert_ref (gimple_stmt_iterator
*gsi
, location_t loc
, tree type
,
1115 const char *name
, enum tree_code code
, tree arg0
)
1117 tree result
= make_temp_ssa_name (type
, NULL
, name
);
1118 gimple stmt
= gimple_build_assign (result
, build1 (code
, type
, arg0
));
1119 gimple_set_location (stmt
, loc
);
1120 gsi_insert_before (gsi
, stmt
, GSI_SAME_STMT
);
1124 /* Build a gimple assignment to cast VAL to TYPE. Insert the statement
1125 prior to GSI's current position, and return the fresh SSA name. */
1128 build_and_insert_cast (gimple_stmt_iterator
*gsi
, location_t loc
,
1129 tree type
, tree val
)
1131 tree result
= make_ssa_name (type
, NULL
);
1132 gimple stmt
= gimple_build_assign_with_ops (NOP_EXPR
, result
, val
);
1133 gimple_set_location (stmt
, loc
);
1134 gsi_insert_before (gsi
, stmt
, GSI_SAME_STMT
);
1138 /* ARG0 and ARG1 are the two arguments to a pow builtin call in GSI
1139 with location info LOC. If possible, create an equivalent and
1140 less expensive sequence of statements prior to GSI, and return an
1141 expession holding the result. */
1144 gimple_expand_builtin_pow (gimple_stmt_iterator
*gsi
, location_t loc
,
1145 tree arg0
, tree arg1
)
1147 REAL_VALUE_TYPE c
, cint
, dconst1_4
, dconst3_4
, dconst1_3
, dconst1_6
;
1148 REAL_VALUE_TYPE c2
, dconst3
;
1150 tree type
, sqrtfn
, cbrtfn
, sqrt_arg0
, sqrt_sqrt
, result
, cbrt_x
, powi_cbrt_x
;
1152 bool hw_sqrt_exists
, c_is_int
, c2_is_int
;
1154 /* If the exponent isn't a constant, there's nothing of interest
1156 if (TREE_CODE (arg1
) != REAL_CST
)
1159 /* If the exponent is equivalent to an integer, expand to an optimal
1160 multiplication sequence when profitable. */
1161 c
= TREE_REAL_CST (arg1
);
1162 n
= real_to_integer (&c
);
1163 real_from_integer (&cint
, VOIDmode
, n
, SIGNED
);
1164 c_is_int
= real_identical (&c
, &cint
);
1167 && ((n
>= -1 && n
<= 2)
1168 || (flag_unsafe_math_optimizations
1169 && optimize_bb_for_speed_p (gsi_bb (*gsi
))
1170 && powi_cost (n
) <= POWI_MAX_MULTS
)))
1171 return gimple_expand_builtin_powi (gsi
, loc
, arg0
, n
);
1173 /* Attempt various optimizations using sqrt and cbrt. */
1174 type
= TREE_TYPE (arg0
);
1175 mode
= TYPE_MODE (type
);
1176 sqrtfn
= mathfn_built_in (type
, BUILT_IN_SQRT
);
1178 /* Optimize pow(x,0.5) = sqrt(x). This replacement is always safe
1179 unless signed zeros must be maintained. pow(-0,0.5) = +0, while
1182 && REAL_VALUES_EQUAL (c
, dconsthalf
)
1183 && !HONOR_SIGNED_ZEROS (mode
))
1184 return build_and_insert_call (gsi
, loc
, sqrtfn
, arg0
);
1186 /* Optimize pow(x,0.25) = sqrt(sqrt(x)). Assume on most machines that
1187 a builtin sqrt instruction is smaller than a call to pow with 0.25,
1188 so do this optimization even if -Os. Don't do this optimization
1189 if we don't have a hardware sqrt insn. */
1190 dconst1_4
= dconst1
;
1191 SET_REAL_EXP (&dconst1_4
, REAL_EXP (&dconst1_4
) - 2);
1192 hw_sqrt_exists
= optab_handler (sqrt_optab
, mode
) != CODE_FOR_nothing
;
1194 if (flag_unsafe_math_optimizations
1196 && REAL_VALUES_EQUAL (c
, dconst1_4
)
1200 sqrt_arg0
= build_and_insert_call (gsi
, loc
, sqrtfn
, arg0
);
1203 return build_and_insert_call (gsi
, loc
, sqrtfn
, sqrt_arg0
);
1206 /* Optimize pow(x,0.75) = sqrt(x) * sqrt(sqrt(x)) unless we are
1207 optimizing for space. Don't do this optimization if we don't have
1208 a hardware sqrt insn. */
1209 real_from_integer (&dconst3_4
, VOIDmode
, 3, SIGNED
);
1210 SET_REAL_EXP (&dconst3_4
, REAL_EXP (&dconst3_4
) - 2);
1212 if (flag_unsafe_math_optimizations
1214 && optimize_function_for_speed_p (cfun
)
1215 && REAL_VALUES_EQUAL (c
, dconst3_4
)
1219 sqrt_arg0
= build_and_insert_call (gsi
, loc
, sqrtfn
, arg0
);
1222 sqrt_sqrt
= build_and_insert_call (gsi
, loc
, sqrtfn
, sqrt_arg0
);
1224 /* sqrt(x) * sqrt(sqrt(x)) */
1225 return build_and_insert_binop (gsi
, loc
, "powroot", MULT_EXPR
,
1226 sqrt_arg0
, sqrt_sqrt
);
1229 /* Optimize pow(x,1./3.) = cbrt(x). This requires unsafe math
1230 optimizations since 1./3. is not exactly representable. If x
1231 is negative and finite, the correct value of pow(x,1./3.) is
1232 a NaN with the "invalid" exception raised, because the value
1233 of 1./3. actually has an even denominator. The correct value
1234 of cbrt(x) is a negative real value. */
1235 cbrtfn
= mathfn_built_in (type
, BUILT_IN_CBRT
);
1236 dconst1_3
= real_value_truncate (mode
, dconst_third ());
1238 if (flag_unsafe_math_optimizations
1240 && (gimple_val_nonnegative_real_p (arg0
) || !HONOR_NANS (mode
))
1241 && REAL_VALUES_EQUAL (c
, dconst1_3
))
1242 return build_and_insert_call (gsi
, loc
, cbrtfn
, arg0
);
1244 /* Optimize pow(x,1./6.) = cbrt(sqrt(x)). Don't do this optimization
1245 if we don't have a hardware sqrt insn. */
1246 dconst1_6
= dconst1_3
;
1247 SET_REAL_EXP (&dconst1_6
, REAL_EXP (&dconst1_6
) - 1);
1249 if (flag_unsafe_math_optimizations
1252 && (gimple_val_nonnegative_real_p (arg0
) || !HONOR_NANS (mode
))
1253 && optimize_function_for_speed_p (cfun
)
1255 && REAL_VALUES_EQUAL (c
, dconst1_6
))
1258 sqrt_arg0
= build_and_insert_call (gsi
, loc
, sqrtfn
, arg0
);
1261 return build_and_insert_call (gsi
, loc
, cbrtfn
, sqrt_arg0
);
1264 /* Optimize pow(x,c), where n = 2c for some nonzero integer n
1265 and c not an integer, into
1267 sqrt(x) * powi(x, n/2), n > 0;
1268 1.0 / (sqrt(x) * powi(x, abs(n/2))), n < 0.
1270 Do not calculate the powi factor when n/2 = 0. */
1271 real_arithmetic (&c2
, MULT_EXPR
, &c
, &dconst2
);
1272 n
= real_to_integer (&c2
);
1273 real_from_integer (&cint
, VOIDmode
, n
, SIGNED
);
1274 c2_is_int
= real_identical (&c2
, &cint
);
1276 if (flag_unsafe_math_optimizations
1280 && optimize_function_for_speed_p (cfun
))
1282 tree powi_x_ndiv2
= NULL_TREE
;
1284 /* Attempt to fold powi(arg0, abs(n/2)) into multiplies. If not
1285 possible or profitable, give up. Skip the degenerate case when
1286 n is 1 or -1, where the result is always 1. */
1287 if (absu_hwi (n
) != 1)
1289 powi_x_ndiv2
= gimple_expand_builtin_powi (gsi
, loc
, arg0
,
1295 /* Calculate sqrt(x). When n is not 1 or -1, multiply it by the
1296 result of the optimal multiply sequence just calculated. */
1297 sqrt_arg0
= build_and_insert_call (gsi
, loc
, sqrtfn
, arg0
);
1299 if (absu_hwi (n
) == 1)
1302 result
= build_and_insert_binop (gsi
, loc
, "powroot", MULT_EXPR
,
1303 sqrt_arg0
, powi_x_ndiv2
);
1305 /* If n is negative, reciprocate the result. */
1307 result
= build_and_insert_binop (gsi
, loc
, "powroot", RDIV_EXPR
,
1308 build_real (type
, dconst1
), result
);
1312 /* Optimize pow(x,c), where 3c = n for some nonzero integer n, into
1314 powi(x, n/3) * powi(cbrt(x), n%3), n > 0;
1315 1.0 / (powi(x, abs(n)/3) * powi(cbrt(x), abs(n)%3)), n < 0.
1317 Do not calculate the first factor when n/3 = 0. As cbrt(x) is
1318 different from pow(x, 1./3.) due to rounding and behavior with
1319 negative x, we need to constrain this transformation to unsafe
1320 math and positive x or finite math. */
1321 real_from_integer (&dconst3
, VOIDmode
, 3, SIGNED
);
1322 real_arithmetic (&c2
, MULT_EXPR
, &c
, &dconst3
);
1323 real_round (&c2
, mode
, &c2
);
1324 n
= real_to_integer (&c2
);
1325 real_from_integer (&cint
, VOIDmode
, n
, SIGNED
);
1326 real_arithmetic (&c2
, RDIV_EXPR
, &cint
, &dconst3
);
1327 real_convert (&c2
, mode
, &c2
);
1329 if (flag_unsafe_math_optimizations
1331 && (gimple_val_nonnegative_real_p (arg0
) || !HONOR_NANS (mode
))
1332 && real_identical (&c2
, &c
)
1334 && optimize_function_for_speed_p (cfun
)
1335 && powi_cost (n
/ 3) <= POWI_MAX_MULTS
)
1337 tree powi_x_ndiv3
= NULL_TREE
;
1339 /* Attempt to fold powi(arg0, abs(n/3)) into multiplies. If not
1340 possible or profitable, give up. Skip the degenerate case when
1341 abs(n) < 3, where the result is always 1. */
1342 if (absu_hwi (n
) >= 3)
1344 powi_x_ndiv3
= gimple_expand_builtin_powi (gsi
, loc
, arg0
,
1350 /* Calculate powi(cbrt(x), n%3). Don't use gimple_expand_builtin_powi
1351 as that creates an unnecessary variable. Instead, just produce
1352 either cbrt(x) or cbrt(x) * cbrt(x). */
1353 cbrt_x
= build_and_insert_call (gsi
, loc
, cbrtfn
, arg0
);
1355 if (absu_hwi (n
) % 3 == 1)
1356 powi_cbrt_x
= cbrt_x
;
1358 powi_cbrt_x
= build_and_insert_binop (gsi
, loc
, "powroot", MULT_EXPR
,
1361 /* Multiply the two subexpressions, unless powi(x,abs(n)/3) = 1. */
1362 if (absu_hwi (n
) < 3)
1363 result
= powi_cbrt_x
;
1365 result
= build_and_insert_binop (gsi
, loc
, "powroot", MULT_EXPR
,
1366 powi_x_ndiv3
, powi_cbrt_x
);
1368 /* If n is negative, reciprocate the result. */
1370 result
= build_and_insert_binop (gsi
, loc
, "powroot", RDIV_EXPR
,
1371 build_real (type
, dconst1
), result
);
1376 /* No optimizations succeeded. */
1380 /* ARG is the argument to a cabs builtin call in GSI with location info
1381 LOC. Create a sequence of statements prior to GSI that calculates
1382 sqrt(R*R + I*I), where R and I are the real and imaginary components
1383 of ARG, respectively. Return an expression holding the result. */
1386 gimple_expand_builtin_cabs (gimple_stmt_iterator
*gsi
, location_t loc
, tree arg
)
1388 tree real_part
, imag_part
, addend1
, addend2
, sum
, result
;
1389 tree type
= TREE_TYPE (TREE_TYPE (arg
));
1390 tree sqrtfn
= mathfn_built_in (type
, BUILT_IN_SQRT
);
1391 machine_mode mode
= TYPE_MODE (type
);
1393 if (!flag_unsafe_math_optimizations
1394 || !optimize_bb_for_speed_p (gimple_bb (gsi_stmt (*gsi
)))
1396 || optab_handler (sqrt_optab
, mode
) == CODE_FOR_nothing
)
1399 real_part
= build_and_insert_ref (gsi
, loc
, type
, "cabs",
1400 REALPART_EXPR
, arg
);
1401 addend1
= build_and_insert_binop (gsi
, loc
, "cabs", MULT_EXPR
,
1402 real_part
, real_part
);
1403 imag_part
= build_and_insert_ref (gsi
, loc
, type
, "cabs",
1404 IMAGPART_EXPR
, arg
);
1405 addend2
= build_and_insert_binop (gsi
, loc
, "cabs", MULT_EXPR
,
1406 imag_part
, imag_part
);
1407 sum
= build_and_insert_binop (gsi
, loc
, "cabs", PLUS_EXPR
, addend1
, addend2
);
1408 result
= build_and_insert_call (gsi
, loc
, sqrtfn
, sum
);
1413 /* Go through all calls to sin, cos and cexpi and call execute_cse_sincos_1
1414 on the SSA_NAME argument of each of them. Also expand powi(x,n) into
1415 an optimal number of multiplies, when n is a constant. */
1419 const pass_data pass_data_cse_sincos
=
1421 GIMPLE_PASS
, /* type */
1422 "sincos", /* name */
1423 OPTGROUP_NONE
, /* optinfo_flags */
1424 TV_NONE
, /* tv_id */
1425 PROP_ssa
, /* properties_required */
1426 0, /* properties_provided */
1427 0, /* properties_destroyed */
1428 0, /* todo_flags_start */
1429 TODO_update_ssa
, /* todo_flags_finish */
1432 class pass_cse_sincos
: public gimple_opt_pass
1435 pass_cse_sincos (gcc::context
*ctxt
)
1436 : gimple_opt_pass (pass_data_cse_sincos
, ctxt
)
1439 /* opt_pass methods: */
1440 virtual bool gate (function
*)
1442 /* We no longer require either sincos or cexp, since powi expansion
1443 piggybacks on this pass. */
1447 virtual unsigned int execute (function
*);
1449 }; // class pass_cse_sincos
1452 pass_cse_sincos::execute (function
*fun
)
1455 bool cfg_changed
= false;
1457 calculate_dominance_info (CDI_DOMINATORS
);
1458 memset (&sincos_stats
, 0, sizeof (sincos_stats
));
1460 FOR_EACH_BB_FN (bb
, fun
)
1462 gimple_stmt_iterator gsi
;
1463 bool cleanup_eh
= false;
1465 for (gsi
= gsi_after_labels (bb
); !gsi_end_p (gsi
); gsi_next (&gsi
))
1467 gimple stmt
= gsi_stmt (gsi
);
1470 /* Only the last stmt in a bb could throw, no need to call
1471 gimple_purge_dead_eh_edges if we change something in the middle
1472 of a basic block. */
1475 if (is_gimple_call (stmt
)
1476 && gimple_call_lhs (stmt
)
1477 && (fndecl
= gimple_call_fndecl (stmt
))
1478 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
1480 tree arg
, arg0
, arg1
, result
;
1484 switch (DECL_FUNCTION_CODE (fndecl
))
1486 CASE_FLT_FN (BUILT_IN_COS
):
1487 CASE_FLT_FN (BUILT_IN_SIN
):
1488 CASE_FLT_FN (BUILT_IN_CEXPI
):
1489 /* Make sure we have either sincos or cexp. */
1490 if (!targetm
.libc_has_function (function_c99_math_complex
)
1491 && !targetm
.libc_has_function (function_sincos
))
1494 arg
= gimple_call_arg (stmt
, 0);
1495 if (TREE_CODE (arg
) == SSA_NAME
)
1496 cfg_changed
|= execute_cse_sincos_1 (arg
);
1499 CASE_FLT_FN (BUILT_IN_POW
):
1500 arg0
= gimple_call_arg (stmt
, 0);
1501 arg1
= gimple_call_arg (stmt
, 1);
1503 loc
= gimple_location (stmt
);
1504 result
= gimple_expand_builtin_pow (&gsi
, loc
, arg0
, arg1
);
1508 tree lhs
= gimple_get_lhs (stmt
);
1509 gimple new_stmt
= gimple_build_assign (lhs
, result
);
1510 gimple_set_location (new_stmt
, loc
);
1511 unlink_stmt_vdef (stmt
);
1512 gsi_replace (&gsi
, new_stmt
, true);
1514 if (gimple_vdef (stmt
))
1515 release_ssa_name (gimple_vdef (stmt
));
1519 CASE_FLT_FN (BUILT_IN_POWI
):
1520 arg0
= gimple_call_arg (stmt
, 0);
1521 arg1
= gimple_call_arg (stmt
, 1);
1522 loc
= gimple_location (stmt
);
1524 if (real_minus_onep (arg0
))
1526 tree t0
, t1
, cond
, one
, minus_one
;
1529 t0
= TREE_TYPE (arg0
);
1530 t1
= TREE_TYPE (arg1
);
1531 one
= build_real (t0
, dconst1
);
1532 minus_one
= build_real (t0
, dconstm1
);
1534 cond
= make_temp_ssa_name (t1
, NULL
, "powi_cond");
1535 stmt
= gimple_build_assign_with_ops (BIT_AND_EXPR
, cond
,
1539 gimple_set_location (stmt
, loc
);
1540 gsi_insert_before (&gsi
, stmt
, GSI_SAME_STMT
);
1542 result
= make_temp_ssa_name (t0
, NULL
, "powi");
1543 stmt
= gimple_build_assign_with_ops (COND_EXPR
, result
,
1546 gimple_set_location (stmt
, loc
);
1547 gsi_insert_before (&gsi
, stmt
, GSI_SAME_STMT
);
1551 if (!tree_fits_shwi_p (arg1
))
1554 n
= tree_to_shwi (arg1
);
1555 result
= gimple_expand_builtin_powi (&gsi
, loc
, arg0
, n
);
1560 tree lhs
= gimple_get_lhs (stmt
);
1561 gimple new_stmt
= gimple_build_assign (lhs
, result
);
1562 gimple_set_location (new_stmt
, loc
);
1563 unlink_stmt_vdef (stmt
);
1564 gsi_replace (&gsi
, new_stmt
, true);
1566 if (gimple_vdef (stmt
))
1567 release_ssa_name (gimple_vdef (stmt
));
1571 CASE_FLT_FN (BUILT_IN_CABS
):
1572 arg0
= gimple_call_arg (stmt
, 0);
1573 loc
= gimple_location (stmt
);
1574 result
= gimple_expand_builtin_cabs (&gsi
, loc
, arg0
);
1578 tree lhs
= gimple_get_lhs (stmt
);
1579 gimple new_stmt
= gimple_build_assign (lhs
, result
);
1580 gimple_set_location (new_stmt
, loc
);
1581 unlink_stmt_vdef (stmt
);
1582 gsi_replace (&gsi
, new_stmt
, true);
1584 if (gimple_vdef (stmt
))
1585 release_ssa_name (gimple_vdef (stmt
));
1594 cfg_changed
|= gimple_purge_dead_eh_edges (bb
);
1597 statistics_counter_event (fun
, "sincos statements inserted",
1598 sincos_stats
.inserted
);
1600 free_dominance_info (CDI_DOMINATORS
);
1601 return cfg_changed
? TODO_cleanup_cfg
: 0;
1607 make_pass_cse_sincos (gcc::context
*ctxt
)
1609 return new pass_cse_sincos (ctxt
);
1612 /* A symbolic number is used to detect byte permutation and selection
1613 patterns. Therefore the field N contains an artificial number
1614 consisting of octet sized markers:
1616 0 - target byte has the value 0
1617 FF - target byte has an unknown value (eg. due to sign extension)
1618 1..size - marker value is the target byte index minus one.
1620 To detect permutations on memory sources (arrays and structures), a symbolic
1621 number is also associated a base address (the array or structure the load is
1622 made from), an offset from the base address and a range which gives the
1623 difference between the highest and lowest accessed memory location to make
1624 such a symbolic number. The range is thus different from size which reflects
1625 the size of the type of current expression. Note that for non memory source,
1626 range holds the same value as size.
1628 For instance, for an array char a[], (short) a[0] | (short) a[3] would have
1629 a size of 2 but a range of 4 while (short) a[0] | ((short) a[0] << 1) would
1630 still have a size of 2 but this time a range of 1. */
1632 struct symbolic_number
{
1637 HOST_WIDE_INT bytepos
;
1640 unsigned HOST_WIDE_INT range
;
1643 #define BITS_PER_MARKER 8
1644 #define MARKER_MASK ((1 << BITS_PER_MARKER) - 1)
1645 #define MARKER_BYTE_UNKNOWN MARKER_MASK
1646 #define HEAD_MARKER(n, size) \
1647 ((n) & ((uint64_t) MARKER_MASK << (((size) - 1) * BITS_PER_MARKER)))
1649 /* The number which the find_bswap_or_nop_1 result should match in
1650 order to have a nop. The number is masked according to the size of
1651 the symbolic number before using it. */
1652 #define CMPNOP (sizeof (int64_t) < 8 ? 0 : \
1653 (uint64_t)0x08070605 << 32 | 0x04030201)
1655 /* The number which the find_bswap_or_nop_1 result should match in
1656 order to have a byte swap. The number is masked according to the
1657 size of the symbolic number before using it. */
1658 #define CMPXCHG (sizeof (int64_t) < 8 ? 0 : \
1659 (uint64_t)0x01020304 << 32 | 0x05060708)
1661 /* Perform a SHIFT or ROTATE operation by COUNT bits on symbolic
1662 number N. Return false if the requested operation is not permitted
1663 on a symbolic number. */
1666 do_shift_rotate (enum tree_code code
,
1667 struct symbolic_number
*n
,
1670 int i
, size
= TYPE_PRECISION (n
->type
) / BITS_PER_UNIT
;
1671 unsigned head_marker
;
1673 if (count
% BITS_PER_UNIT
!= 0)
1675 count
= (count
/ BITS_PER_UNIT
) * BITS_PER_MARKER
;
1677 /* Zero out the extra bits of N in order to avoid them being shifted
1678 into the significant bits. */
1679 if (size
< 64 / BITS_PER_MARKER
)
1680 n
->n
&= ((uint64_t) 1 << (size
* BITS_PER_MARKER
)) - 1;
1688 head_marker
= HEAD_MARKER (n
->n
, size
);
1690 /* Arithmetic shift of signed type: result is dependent on the value. */
1691 if (!TYPE_UNSIGNED (n
->type
) && head_marker
)
1692 for (i
= 0; i
< count
/ BITS_PER_MARKER
; i
++)
1693 n
->n
|= (uint64_t) MARKER_BYTE_UNKNOWN
1694 << ((size
- 1 - i
) * BITS_PER_MARKER
);
1697 n
->n
= (n
->n
<< count
) | (n
->n
>> ((size
* BITS_PER_MARKER
) - count
));
1700 n
->n
= (n
->n
>> count
) | (n
->n
<< ((size
* BITS_PER_MARKER
) - count
));
1705 /* Zero unused bits for size. */
1706 if (size
< 64 / BITS_PER_MARKER
)
1707 n
->n
&= ((uint64_t) 1 << (size
* BITS_PER_MARKER
)) - 1;
1711 /* Perform sanity checking for the symbolic number N and the gimple
1715 verify_symbolic_number_p (struct symbolic_number
*n
, gimple stmt
)
1719 lhs_type
= gimple_expr_type (stmt
);
1721 if (TREE_CODE (lhs_type
) != INTEGER_TYPE
)
1724 if (TYPE_PRECISION (lhs_type
) != TYPE_PRECISION (n
->type
))
1730 /* Initialize the symbolic number N for the bswap pass from the base element
1731 SRC manipulated by the bitwise OR expression. */
1734 init_symbolic_number (struct symbolic_number
*n
, tree src
)
1738 n
->base_addr
= n
->offset
= n
->alias_set
= n
->vuse
= NULL_TREE
;
1740 /* Set up the symbolic number N by setting each byte to a value between 1 and
1741 the byte size of rhs1. The highest order byte is set to n->size and the
1742 lowest order byte to 1. */
1743 n
->type
= TREE_TYPE (src
);
1744 size
= TYPE_PRECISION (n
->type
);
1745 if (size
% BITS_PER_UNIT
!= 0)
1747 size
/= BITS_PER_UNIT
;
1748 if (size
> 64 / BITS_PER_MARKER
)
1753 if (size
< 64 / BITS_PER_MARKER
)
1754 n
->n
&= ((uint64_t) 1 << (size
* BITS_PER_MARKER
)) - 1;
1759 /* Check if STMT might be a byte swap or a nop from a memory source and returns
1760 the answer. If so, REF is that memory source and the base of the memory area
1761 accessed and the offset of the access from that base are recorded in N. */
1764 find_bswap_or_nop_load (gimple stmt
, tree ref
, struct symbolic_number
*n
)
1766 /* Leaf node is an array or component ref. Memorize its base and
1767 offset from base to compare to other such leaf node. */
1768 HOST_WIDE_INT bitsize
, bitpos
;
1770 int unsignedp
, volatilep
;
1771 tree offset
, base_addr
;
1773 if (!gimple_assign_load_p (stmt
) || gimple_has_volatile_ops (stmt
))
1776 base_addr
= get_inner_reference (ref
, &bitsize
, &bitpos
, &offset
, &mode
,
1777 &unsignedp
, &volatilep
, false);
1779 if (TREE_CODE (base_addr
) == MEM_REF
)
1781 offset_int bit_offset
= 0;
1782 tree off
= TREE_OPERAND (base_addr
, 1);
1784 if (!integer_zerop (off
))
1786 offset_int boff
, coff
= mem_ref_offset (base_addr
);
1787 boff
= wi::lshift (coff
, LOG2_BITS_PER_UNIT
);
1791 base_addr
= TREE_OPERAND (base_addr
, 0);
1793 /* Avoid returning a negative bitpos as this may wreak havoc later. */
1794 if (wi::neg_p (bit_offset
))
1796 offset_int mask
= wi::mask
<offset_int
> (LOG2_BITS_PER_UNIT
, false);
1797 offset_int tem
= bit_offset
.and_not (mask
);
1798 /* TEM is the bitpos rounded to BITS_PER_UNIT towards -Inf.
1799 Subtract it to BIT_OFFSET and add it (scaled) to OFFSET. */
1801 tem
= wi::arshift (tem
, LOG2_BITS_PER_UNIT
);
1803 offset
= size_binop (PLUS_EXPR
, offset
,
1804 wide_int_to_tree (sizetype
, tem
));
1806 offset
= wide_int_to_tree (sizetype
, tem
);
1809 bitpos
+= bit_offset
.to_shwi ();
1812 if (bitpos
% BITS_PER_UNIT
)
1814 if (bitsize
% BITS_PER_UNIT
)
1817 if (!init_symbolic_number (n
, ref
))
1819 n
->base_addr
= base_addr
;
1821 n
->bytepos
= bitpos
/ BITS_PER_UNIT
;
1822 n
->alias_set
= reference_alias_ptr_type (ref
);
1823 n
->vuse
= gimple_vuse (stmt
);
1827 /* find_bswap_or_nop_1 invokes itself recursively with N and tries to perform
1828 the operation given by the rhs of STMT on the result. If the operation
1829 could successfully be executed the function returns a gimple stmt whose
1830 rhs's first tree is the expression of the source operand and NULL
1834 find_bswap_or_nop_1 (gimple stmt
, struct symbolic_number
*n
, int limit
)
1836 enum tree_code code
;
1837 tree rhs1
, rhs2
= NULL
;
1838 gimple rhs1_stmt
, rhs2_stmt
, source_stmt1
;
1839 enum gimple_rhs_class rhs_class
;
1841 if (!limit
|| !is_gimple_assign (stmt
))
1844 rhs1
= gimple_assign_rhs1 (stmt
);
1846 if (find_bswap_or_nop_load (stmt
, rhs1
, n
))
1849 if (TREE_CODE (rhs1
) != SSA_NAME
)
1852 code
= gimple_assign_rhs_code (stmt
);
1853 rhs_class
= gimple_assign_rhs_class (stmt
);
1854 rhs1_stmt
= SSA_NAME_DEF_STMT (rhs1
);
1856 if (rhs_class
== GIMPLE_BINARY_RHS
)
1857 rhs2
= gimple_assign_rhs2 (stmt
);
1859 /* Handle unary rhs and binary rhs with integer constants as second
1862 if (rhs_class
== GIMPLE_UNARY_RHS
1863 || (rhs_class
== GIMPLE_BINARY_RHS
1864 && TREE_CODE (rhs2
) == INTEGER_CST
))
1866 if (code
!= BIT_AND_EXPR
1867 && code
!= LSHIFT_EXPR
1868 && code
!= RSHIFT_EXPR
1869 && code
!= LROTATE_EXPR
1870 && code
!= RROTATE_EXPR
1871 && !CONVERT_EXPR_CODE_P (code
))
1874 source_stmt1
= find_bswap_or_nop_1 (rhs1_stmt
, n
, limit
- 1);
1876 /* If find_bswap_or_nop_1 returned NULL, STMT is a leaf node and
1877 we have to initialize the symbolic number. */
1880 if (gimple_assign_load_p (stmt
)
1881 || !init_symbolic_number (n
, rhs1
))
1883 source_stmt1
= stmt
;
1890 int i
, size
= TYPE_PRECISION (n
->type
) / BITS_PER_UNIT
;
1891 uint64_t val
= int_cst_value (rhs2
), mask
= 0;
1892 uint64_t tmp
= (1 << BITS_PER_UNIT
) - 1;
1894 /* Only constants masking full bytes are allowed. */
1895 for (i
= 0; i
< size
; i
++, tmp
<<= BITS_PER_UNIT
)
1896 if ((val
& tmp
) != 0 && (val
& tmp
) != tmp
)
1899 mask
|= (uint64_t) MARKER_MASK
<< (i
* BITS_PER_MARKER
);
1908 if (!do_shift_rotate (code
, n
, (int)TREE_INT_CST_LOW (rhs2
)))
1913 int i
, type_size
, old_type_size
;
1916 type
= gimple_expr_type (stmt
);
1917 type_size
= TYPE_PRECISION (type
);
1918 if (type_size
% BITS_PER_UNIT
!= 0)
1920 type_size
/= BITS_PER_UNIT
;
1921 if (type_size
> 64 / BITS_PER_MARKER
)
1924 /* Sign extension: result is dependent on the value. */
1925 old_type_size
= TYPE_PRECISION (n
->type
) / BITS_PER_UNIT
;
1926 if (!TYPE_UNSIGNED (n
->type
) && type_size
> old_type_size
1927 && HEAD_MARKER (n
->n
, old_type_size
))
1928 for (i
= 0; i
< type_size
- old_type_size
; i
++)
1929 n
->n
|= (uint64_t) MARKER_BYTE_UNKNOWN
1930 << ((type_size
- 1 - i
) * BITS_PER_MARKER
);
1932 if (type_size
< 64 / BITS_PER_MARKER
)
1934 /* If STMT casts to a smaller type mask out the bits not
1935 belonging to the target type. */
1936 n
->n
&= ((uint64_t) 1 << (type_size
* BITS_PER_MARKER
)) - 1;
1940 n
->range
= type_size
;
1946 return verify_symbolic_number_p (n
, stmt
) ? source_stmt1
: NULL
;
1949 /* Handle binary rhs. */
1951 if (rhs_class
== GIMPLE_BINARY_RHS
)
1954 struct symbolic_number n1
, n2
;
1956 gimple source_stmt2
;
1958 if (code
!= BIT_IOR_EXPR
)
1961 if (TREE_CODE (rhs2
) != SSA_NAME
)
1964 rhs2_stmt
= SSA_NAME_DEF_STMT (rhs2
);
1969 source_stmt1
= find_bswap_or_nop_1 (rhs1_stmt
, &n1
, limit
- 1);
1974 source_stmt2
= find_bswap_or_nop_1 (rhs2_stmt
, &n2
, limit
- 1);
1979 if (TYPE_PRECISION (n1
.type
) != TYPE_PRECISION (n2
.type
))
1982 if (!n1
.vuse
!= !n2
.vuse
||
1983 (n1
.vuse
&& !operand_equal_p (n1
.vuse
, n2
.vuse
, 0)))
1986 if (gimple_assign_rhs1 (source_stmt1
)
1987 != gimple_assign_rhs1 (source_stmt2
))
1990 HOST_WIDE_INT off_sub
;
1991 struct symbolic_number
*n_ptr
;
1993 if (!n1
.base_addr
|| !n2
.base_addr
1994 || !operand_equal_p (n1
.base_addr
, n2
.base_addr
, 0))
1996 if (!n1
.offset
!= !n2
.offset
||
1997 (n1
.offset
&& !operand_equal_p (n1
.offset
, n2
.offset
, 0)))
2000 /* We swap n1 with n2 to have n1 < n2. */
2001 if (n2
.bytepos
< n1
.bytepos
)
2003 struct symbolic_number tmpn
;
2008 source_stmt1
= source_stmt2
;
2011 off_sub
= n2
.bytepos
- n1
.bytepos
;
2013 /* Check that the range of memory covered can be represented by
2014 a symbolic number. */
2015 if (off_sub
+ n2
.range
> 64 / BITS_PER_MARKER
)
2017 n
->range
= n2
.range
+ off_sub
;
2019 /* Reinterpret byte marks in symbolic number holding the value of
2020 bigger weight according to target endianness. */
2021 inc
= BYTES_BIG_ENDIAN
? off_sub
+ n2
.range
- n1
.range
: off_sub
;
2022 size
= TYPE_PRECISION (n1
.type
) / BITS_PER_UNIT
;
2023 if (BYTES_BIG_ENDIAN
)
2027 for (i
= 0; i
< size
; i
++, inc
<<= BITS_PER_MARKER
)
2030 (n_ptr
->n
>> (i
* BITS_PER_MARKER
)) & MARKER_MASK
;
2031 if (marker
&& marker
!= MARKER_BYTE_UNKNOWN
)
2036 n
->range
= n1
.range
;
2039 || alias_ptr_types_compatible_p (n1
.alias_set
, n2
.alias_set
))
2040 n
->alias_set
= n1
.alias_set
;
2042 n
->alias_set
= ptr_type_node
;
2044 n
->base_addr
= n1
.base_addr
;
2045 n
->offset
= n1
.offset
;
2046 n
->bytepos
= n1
.bytepos
;
2048 size
= TYPE_PRECISION (n
->type
) / BITS_PER_UNIT
;
2049 for (i
= 0, mask
= MARKER_MASK
; i
< size
;
2050 i
++, mask
<<= BITS_PER_MARKER
)
2052 uint64_t masked1
, masked2
;
2054 masked1
= n1
.n
& mask
;
2055 masked2
= n2
.n
& mask
;
2056 if (masked1
&& masked2
&& masked1
!= masked2
)
2061 if (!verify_symbolic_number_p (n
, stmt
))
2068 return source_stmt1
;
2073 /* Check if STMT completes a bswap implementation or a read in a given
2074 endianness consisting of ORs, SHIFTs and ANDs and sets *BSWAP
2075 accordingly. It also sets N to represent the kind of operations
2076 performed: size of the resulting expression and whether it works on
2077 a memory source, and if so alias-set and vuse. At last, the
2078 function returns a stmt whose rhs's first tree is the source
2082 find_bswap_or_nop (gimple stmt
, struct symbolic_number
*n
, bool *bswap
)
2084 /* The number which the find_bswap_or_nop_1 result should match in order
2085 to have a full byte swap. The number is shifted to the right
2086 according to the size of the symbolic number before using it. */
2087 uint64_t cmpxchg
= CMPXCHG
;
2088 uint64_t cmpnop
= CMPNOP
;
2093 /* The last parameter determines the depth search limit. It usually
2094 correlates directly to the number n of bytes to be touched. We
2095 increase that number by log2(n) + 1 here in order to also
2096 cover signed -> unsigned conversions of the src operand as can be seen
2097 in libgcc, and for initial shift/and operation of the src operand. */
2098 limit
= TREE_INT_CST_LOW (TYPE_SIZE_UNIT (gimple_expr_type (stmt
)));
2099 limit
+= 1 + (int) ceil_log2 ((unsigned HOST_WIDE_INT
) limit
);
2100 source_stmt
= find_bswap_or_nop_1 (stmt
, n
, limit
);
2105 /* Find real size of result (highest non zero byte). */
2111 for (tmpn
= n
->n
, rsize
= 0; tmpn
; tmpn
>>= BITS_PER_MARKER
, rsize
++);
2115 /* Zero out the extra bits of N and CMP*. */
2116 if (n
->range
< (int) sizeof (int64_t))
2120 mask
= ((uint64_t) 1 << (n
->range
* BITS_PER_MARKER
)) - 1;
2121 cmpxchg
>>= (64 / BITS_PER_MARKER
- n
->range
) * BITS_PER_MARKER
;
2125 /* A complete byte swap should make the symbolic number to start with
2126 the largest digit in the highest order byte. Unchanged symbolic
2127 number indicates a read with same endianness as target architecture. */
2130 else if (n
->n
== cmpxchg
)
2135 /* Useless bit manipulation performed by code. */
2136 if (!n
->base_addr
&& n
->n
== cmpnop
)
2139 n
->range
*= BITS_PER_UNIT
;
2145 const pass_data pass_data_optimize_bswap
=
2147 GIMPLE_PASS
, /* type */
2149 OPTGROUP_NONE
, /* optinfo_flags */
2150 TV_NONE
, /* tv_id */
2151 PROP_ssa
, /* properties_required */
2152 0, /* properties_provided */
2153 0, /* properties_destroyed */
2154 0, /* todo_flags_start */
2155 0, /* todo_flags_finish */
2158 class pass_optimize_bswap
: public gimple_opt_pass
2161 pass_optimize_bswap (gcc::context
*ctxt
)
2162 : gimple_opt_pass (pass_data_optimize_bswap
, ctxt
)
2165 /* opt_pass methods: */
2166 virtual bool gate (function
*)
2168 return flag_expensive_optimizations
&& optimize
;
2171 virtual unsigned int execute (function
*);
2173 }; // class pass_optimize_bswap
2175 /* Perform the bswap optimization: replace the expression computed in the rhs
2176 of CUR_STMT by an equivalent bswap, load or load + bswap expression.
2177 Which of these alternatives replace the rhs is given by N->base_addr (non
2178 null if a load is needed) and BSWAP. The type, VUSE and set-alias of the
2179 load to perform are also given in N while the builtin bswap invoke is given
2180 in FNDEL. Finally, if a load is involved, SRC_STMT refers to one of the
2181 load statements involved to construct the rhs in CUR_STMT and N->range gives
2182 the size of the rhs expression for maintaining some statistics.
2184 Note that if the replacement involve a load, CUR_STMT is moved just after
2185 SRC_STMT to do the load with the same VUSE which can lead to CUR_STMT
2186 changing of basic block. */
2189 bswap_replace (gimple cur_stmt
, gimple src_stmt
, tree fndecl
, tree bswap_type
,
2190 tree load_type
, struct symbolic_number
*n
, bool bswap
)
2192 gimple_stmt_iterator gsi
;
2196 gsi
= gsi_for_stmt (cur_stmt
);
2197 src
= gimple_assign_rhs1 (src_stmt
);
2198 tgt
= gimple_assign_lhs (cur_stmt
);
2200 /* Need to load the value from memory first. */
2203 gimple_stmt_iterator gsi_ins
= gsi_for_stmt (src_stmt
);
2204 tree addr_expr
, addr_tmp
, val_expr
, val_tmp
;
2205 tree load_offset_ptr
, aligned_load_type
;
2206 gimple addr_stmt
, load_stmt
;
2209 align
= get_object_alignment (src
);
2211 && align
< GET_MODE_ALIGNMENT (TYPE_MODE (load_type
))
2212 && SLOW_UNALIGNED_ACCESS (TYPE_MODE (load_type
), align
))
2215 /* Move cur_stmt just before one of the load of the original
2216 to ensure it has the same VUSE. See PR61517 for what could
2218 gsi_move_before (&gsi
, &gsi_ins
);
2219 gsi
= gsi_for_stmt (cur_stmt
);
2221 /* Compute address to load from and cast according to the size
2223 addr_expr
= build_fold_addr_expr (unshare_expr (src
));
2224 if (is_gimple_min_invariant (addr_expr
))
2225 addr_tmp
= addr_expr
;
2228 addr_tmp
= make_temp_ssa_name (TREE_TYPE (addr_expr
), NULL
,
2230 addr_stmt
= gimple_build_assign (addr_tmp
, addr_expr
);
2231 gsi_insert_before (&gsi
, addr_stmt
, GSI_SAME_STMT
);
2234 /* Perform the load. */
2235 aligned_load_type
= load_type
;
2236 if (align
< TYPE_ALIGN (load_type
))
2237 aligned_load_type
= build_aligned_type (load_type
, align
);
2238 load_offset_ptr
= build_int_cst (n
->alias_set
, 0);
2239 val_expr
= fold_build2 (MEM_REF
, aligned_load_type
, addr_tmp
,
2245 nop_stats
.found_16bit
++;
2246 else if (n
->range
== 32)
2247 nop_stats
.found_32bit
++;
2250 gcc_assert (n
->range
== 64);
2251 nop_stats
.found_64bit
++;
2254 /* Convert the result of load if necessary. */
2255 if (!useless_type_conversion_p (TREE_TYPE (tgt
), load_type
))
2257 val_tmp
= make_temp_ssa_name (aligned_load_type
, NULL
,
2259 load_stmt
= gimple_build_assign (val_tmp
, val_expr
);
2260 gimple_set_vuse (load_stmt
, n
->vuse
);
2261 gsi_insert_before (&gsi
, load_stmt
, GSI_SAME_STMT
);
2262 gimple_assign_set_rhs_with_ops (&gsi
, NOP_EXPR
, val_tmp
);
2266 gimple_assign_set_rhs_with_ops (&gsi
, MEM_REF
, val_expr
);
2267 gimple_set_vuse (cur_stmt
, n
->vuse
);
2269 update_stmt (cur_stmt
);
2274 "%d bit load in target endianness found at: ",
2276 print_gimple_stmt (dump_file
, cur_stmt
, 0, 0);
2282 val_tmp
= make_temp_ssa_name (aligned_load_type
, NULL
, "load_dst");
2283 load_stmt
= gimple_build_assign (val_tmp
, val_expr
);
2284 gimple_set_vuse (load_stmt
, n
->vuse
);
2285 gsi_insert_before (&gsi
, load_stmt
, GSI_SAME_STMT
);
2291 bswap_stats
.found_16bit
++;
2292 else if (n
->range
== 32)
2293 bswap_stats
.found_32bit
++;
2296 gcc_assert (n
->range
== 64);
2297 bswap_stats
.found_64bit
++;
2302 /* Canonical form for 16 bit bswap is a rotate expression. Only 16bit values
2303 are considered as rotation of 2N bit values by N bits is generally not
2304 equivalent to a bswap. Consider for instance 0x01020304 >> 16 which gives
2305 0x03040102 while a bswap for that value is 0x04030201. */
2306 if (bswap
&& n
->range
== 16)
2308 tree count
= build_int_cst (NULL
, BITS_PER_UNIT
);
2309 bswap_type
= TREE_TYPE (src
);
2310 src
= fold_build2 (LROTATE_EXPR
, bswap_type
, src
, count
);
2311 bswap_stmt
= gimple_build_assign (NULL
, src
);
2315 /* Convert the src expression if necessary. */
2316 if (!useless_type_conversion_p (TREE_TYPE (tmp
), bswap_type
))
2318 gimple convert_stmt
;
2319 tmp
= make_temp_ssa_name (bswap_type
, NULL
, "bswapsrc");
2320 convert_stmt
= gimple_build_assign_with_ops (NOP_EXPR
, tmp
, src
);
2321 gsi_insert_before (&gsi
, convert_stmt
, GSI_SAME_STMT
);
2324 bswap_stmt
= gimple_build_call (fndecl
, 1, tmp
);
2329 /* Convert the result if necessary. */
2330 if (!useless_type_conversion_p (TREE_TYPE (tgt
), bswap_type
))
2332 gimple convert_stmt
;
2333 tmp
= make_temp_ssa_name (bswap_type
, NULL
, "bswapdst");
2334 convert_stmt
= gimple_build_assign_with_ops (NOP_EXPR
, tgt
, tmp
);
2335 gsi_insert_after (&gsi
, convert_stmt
, GSI_SAME_STMT
);
2338 gimple_set_lhs (bswap_stmt
, tmp
);
2342 fprintf (dump_file
, "%d bit bswap implementation found at: ",
2344 print_gimple_stmt (dump_file
, cur_stmt
, 0, 0);
2347 gsi_insert_after (&gsi
, bswap_stmt
, GSI_SAME_STMT
);
2348 gsi_remove (&gsi
, true);
2352 /* Find manual byte swap implementations as well as load in a given
2353 endianness. Byte swaps are turned into a bswap builtin invokation
2354 while endian loads are converted to bswap builtin invokation or
2355 simple load according to the target endianness. */
2358 pass_optimize_bswap::execute (function
*fun
)
2361 bool bswap16_p
, bswap32_p
, bswap64_p
;
2362 bool changed
= false;
2363 tree bswap16_type
= NULL_TREE
, bswap32_type
= NULL_TREE
, bswap64_type
= NULL_TREE
;
2365 if (BITS_PER_UNIT
!= 8)
2368 bswap16_p
= (builtin_decl_explicit_p (BUILT_IN_BSWAP16
)
2369 && optab_handler (bswap_optab
, HImode
) != CODE_FOR_nothing
);
2370 bswap32_p
= (builtin_decl_explicit_p (BUILT_IN_BSWAP32
)
2371 && optab_handler (bswap_optab
, SImode
) != CODE_FOR_nothing
);
2372 bswap64_p
= (builtin_decl_explicit_p (BUILT_IN_BSWAP64
)
2373 && (optab_handler (bswap_optab
, DImode
) != CODE_FOR_nothing
2374 || (bswap32_p
&& word_mode
== SImode
)));
2376 /* Determine the argument type of the builtins. The code later on
2377 assumes that the return and argument type are the same. */
2380 tree fndecl
= builtin_decl_explicit (BUILT_IN_BSWAP16
);
2381 bswap16_type
= TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (fndecl
)));
2386 tree fndecl
= builtin_decl_explicit (BUILT_IN_BSWAP32
);
2387 bswap32_type
= TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (fndecl
)));
2392 tree fndecl
= builtin_decl_explicit (BUILT_IN_BSWAP64
);
2393 bswap64_type
= TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (fndecl
)));
2396 memset (&nop_stats
, 0, sizeof (nop_stats
));
2397 memset (&bswap_stats
, 0, sizeof (bswap_stats
));
2399 FOR_EACH_BB_FN (bb
, fun
)
2401 gimple_stmt_iterator gsi
;
2403 /* We do a reverse scan for bswap patterns to make sure we get the
2404 widest match. As bswap pattern matching doesn't handle previously
2405 inserted smaller bswap replacements as sub-patterns, the wider
2406 variant wouldn't be detected. */
2407 for (gsi
= gsi_last_bb (bb
); !gsi_end_p (gsi
);)
2409 gimple src_stmt
, cur_stmt
= gsi_stmt (gsi
);
2410 tree fndecl
= NULL_TREE
, bswap_type
= NULL_TREE
, load_type
;
2411 enum tree_code code
;
2412 struct symbolic_number n
;
2415 /* This gsi_prev (&gsi) is not part of the for loop because cur_stmt
2416 might be moved to a different basic block by bswap_replace and gsi
2417 must not points to it if that's the case. Moving the gsi_prev
2418 there make sure that gsi points to the statement previous to
2419 cur_stmt while still making sure that all statements are
2420 considered in this basic block. */
2423 if (!is_gimple_assign (cur_stmt
))
2426 code
= gimple_assign_rhs_code (cur_stmt
);
2431 if (!tree_fits_uhwi_p (gimple_assign_rhs2 (cur_stmt
))
2432 || tree_to_uhwi (gimple_assign_rhs2 (cur_stmt
))
2442 src_stmt
= find_bswap_or_nop (cur_stmt
, &n
, &bswap
);
2450 /* Already in canonical form, nothing to do. */
2451 if (code
== LROTATE_EXPR
|| code
== RROTATE_EXPR
)
2453 load_type
= uint16_type_node
;
2456 fndecl
= builtin_decl_explicit (BUILT_IN_BSWAP16
);
2457 bswap_type
= bswap16_type
;
2461 load_type
= uint32_type_node
;
2464 fndecl
= builtin_decl_explicit (BUILT_IN_BSWAP32
);
2465 bswap_type
= bswap32_type
;
2469 load_type
= uint64_type_node
;
2472 fndecl
= builtin_decl_explicit (BUILT_IN_BSWAP64
);
2473 bswap_type
= bswap64_type
;
2480 if (bswap
&& !fndecl
)
2483 if (bswap_replace (cur_stmt
, src_stmt
, fndecl
, bswap_type
, load_type
,
2489 statistics_counter_event (fun
, "16-bit nop implementations found",
2490 nop_stats
.found_16bit
);
2491 statistics_counter_event (fun
, "32-bit nop implementations found",
2492 nop_stats
.found_32bit
);
2493 statistics_counter_event (fun
, "64-bit nop implementations found",
2494 nop_stats
.found_64bit
);
2495 statistics_counter_event (fun
, "16-bit bswap implementations found",
2496 bswap_stats
.found_16bit
);
2497 statistics_counter_event (fun
, "32-bit bswap implementations found",
2498 bswap_stats
.found_32bit
);
2499 statistics_counter_event (fun
, "64-bit bswap implementations found",
2500 bswap_stats
.found_64bit
);
2502 return (changed
? TODO_update_ssa
: 0);
2508 make_pass_optimize_bswap (gcc::context
*ctxt
)
2510 return new pass_optimize_bswap (ctxt
);
2513 /* Return true if stmt is a type conversion operation that can be stripped
2514 when used in a widening multiply operation. */
2516 widening_mult_conversion_strippable_p (tree result_type
, gimple stmt
)
2518 enum tree_code rhs_code
= gimple_assign_rhs_code (stmt
);
2520 if (TREE_CODE (result_type
) == INTEGER_TYPE
)
2525 if (!CONVERT_EXPR_CODE_P (rhs_code
))
2528 op_type
= TREE_TYPE (gimple_assign_lhs (stmt
));
2530 /* If the type of OP has the same precision as the result, then
2531 we can strip this conversion. The multiply operation will be
2532 selected to create the correct extension as a by-product. */
2533 if (TYPE_PRECISION (result_type
) == TYPE_PRECISION (op_type
))
2536 /* We can also strip a conversion if it preserves the signed-ness of
2537 the operation and doesn't narrow the range. */
2538 inner_op_type
= TREE_TYPE (gimple_assign_rhs1 (stmt
));
2540 /* If the inner-most type is unsigned, then we can strip any
2541 intermediate widening operation. If it's signed, then the
2542 intermediate widening operation must also be signed. */
2543 if ((TYPE_UNSIGNED (inner_op_type
)
2544 || TYPE_UNSIGNED (op_type
) == TYPE_UNSIGNED (inner_op_type
))
2545 && TYPE_PRECISION (op_type
) > TYPE_PRECISION (inner_op_type
))
2551 return rhs_code
== FIXED_CONVERT_EXPR
;
2554 /* Return true if RHS is a suitable operand for a widening multiplication,
2555 assuming a target type of TYPE.
2556 There are two cases:
2558 - RHS makes some value at least twice as wide. Store that value
2559 in *NEW_RHS_OUT if so, and store its type in *TYPE_OUT.
2561 - RHS is an integer constant. Store that value in *NEW_RHS_OUT if so,
2562 but leave *TYPE_OUT untouched. */
2565 is_widening_mult_rhs_p (tree type
, tree rhs
, tree
*type_out
,
2571 if (TREE_CODE (rhs
) == SSA_NAME
)
2573 stmt
= SSA_NAME_DEF_STMT (rhs
);
2574 if (is_gimple_assign (stmt
))
2576 if (! widening_mult_conversion_strippable_p (type
, stmt
))
2580 rhs1
= gimple_assign_rhs1 (stmt
);
2582 if (TREE_CODE (rhs1
) == INTEGER_CST
)
2584 *new_rhs_out
= rhs1
;
2593 type1
= TREE_TYPE (rhs1
);
2595 if (TREE_CODE (type1
) != TREE_CODE (type
)
2596 || TYPE_PRECISION (type1
) * 2 > TYPE_PRECISION (type
))
2599 *new_rhs_out
= rhs1
;
2604 if (TREE_CODE (rhs
) == INTEGER_CST
)
2614 /* Return true if STMT performs a widening multiplication, assuming the
2615 output type is TYPE. If so, store the unwidened types of the operands
2616 in *TYPE1_OUT and *TYPE2_OUT respectively. Also fill *RHS1_OUT and
2617 *RHS2_OUT such that converting those operands to types *TYPE1_OUT
2618 and *TYPE2_OUT would give the operands of the multiplication. */
2621 is_widening_mult_p (gimple stmt
,
2622 tree
*type1_out
, tree
*rhs1_out
,
2623 tree
*type2_out
, tree
*rhs2_out
)
2625 tree type
= TREE_TYPE (gimple_assign_lhs (stmt
));
2627 if (TREE_CODE (type
) != INTEGER_TYPE
2628 && TREE_CODE (type
) != FIXED_POINT_TYPE
)
2631 if (!is_widening_mult_rhs_p (type
, gimple_assign_rhs1 (stmt
), type1_out
,
2635 if (!is_widening_mult_rhs_p (type
, gimple_assign_rhs2 (stmt
), type2_out
,
2639 if (*type1_out
== NULL
)
2641 if (*type2_out
== NULL
|| !int_fits_type_p (*rhs1_out
, *type2_out
))
2643 *type1_out
= *type2_out
;
2646 if (*type2_out
== NULL
)
2648 if (!int_fits_type_p (*rhs2_out
, *type1_out
))
2650 *type2_out
= *type1_out
;
2653 /* Ensure that the larger of the two operands comes first. */
2654 if (TYPE_PRECISION (*type1_out
) < TYPE_PRECISION (*type2_out
))
2658 *type1_out
= *type2_out
;
2661 *rhs1_out
= *rhs2_out
;
2668 /* Process a single gimple statement STMT, which has a MULT_EXPR as
2669 its rhs, and try to convert it into a WIDEN_MULT_EXPR. The return
2670 value is true iff we converted the statement. */
2673 convert_mult_to_widen (gimple stmt
, gimple_stmt_iterator
*gsi
)
2675 tree lhs
, rhs1
, rhs2
, type
, type1
, type2
;
2676 enum insn_code handler
;
2677 machine_mode to_mode
, from_mode
, actual_mode
;
2679 int actual_precision
;
2680 location_t loc
= gimple_location (stmt
);
2681 bool from_unsigned1
, from_unsigned2
;
2683 lhs
= gimple_assign_lhs (stmt
);
2684 type
= TREE_TYPE (lhs
);
2685 if (TREE_CODE (type
) != INTEGER_TYPE
)
2688 if (!is_widening_mult_p (stmt
, &type1
, &rhs1
, &type2
, &rhs2
))
2691 to_mode
= TYPE_MODE (type
);
2692 from_mode
= TYPE_MODE (type1
);
2693 from_unsigned1
= TYPE_UNSIGNED (type1
);
2694 from_unsigned2
= TYPE_UNSIGNED (type2
);
2696 if (from_unsigned1
&& from_unsigned2
)
2697 op
= umul_widen_optab
;
2698 else if (!from_unsigned1
&& !from_unsigned2
)
2699 op
= smul_widen_optab
;
2701 op
= usmul_widen_optab
;
2703 handler
= find_widening_optab_handler_and_mode (op
, to_mode
, from_mode
,
2706 if (handler
== CODE_FOR_nothing
)
2708 if (op
!= smul_widen_optab
)
2710 /* We can use a signed multiply with unsigned types as long as
2711 there is a wider mode to use, or it is the smaller of the two
2712 types that is unsigned. Note that type1 >= type2, always. */
2713 if ((TYPE_UNSIGNED (type1
)
2714 && TYPE_PRECISION (type1
) == GET_MODE_PRECISION (from_mode
))
2715 || (TYPE_UNSIGNED (type2
)
2716 && TYPE_PRECISION (type2
) == GET_MODE_PRECISION (from_mode
)))
2718 from_mode
= GET_MODE_WIDER_MODE (from_mode
);
2719 if (GET_MODE_SIZE (to_mode
) <= GET_MODE_SIZE (from_mode
))
2723 op
= smul_widen_optab
;
2724 handler
= find_widening_optab_handler_and_mode (op
, to_mode
,
2728 if (handler
== CODE_FOR_nothing
)
2731 from_unsigned1
= from_unsigned2
= false;
2737 /* Ensure that the inputs to the handler are in the correct precison
2738 for the opcode. This will be the full mode size. */
2739 actual_precision
= GET_MODE_PRECISION (actual_mode
);
2740 if (2 * actual_precision
> TYPE_PRECISION (type
))
2742 if (actual_precision
!= TYPE_PRECISION (type1
)
2743 || from_unsigned1
!= TYPE_UNSIGNED (type1
))
2744 rhs1
= build_and_insert_cast (gsi
, loc
,
2745 build_nonstandard_integer_type
2746 (actual_precision
, from_unsigned1
), rhs1
);
2747 if (actual_precision
!= TYPE_PRECISION (type2
)
2748 || from_unsigned2
!= TYPE_UNSIGNED (type2
))
2749 rhs2
= build_and_insert_cast (gsi
, loc
,
2750 build_nonstandard_integer_type
2751 (actual_precision
, from_unsigned2
), rhs2
);
2753 /* Handle constants. */
2754 if (TREE_CODE (rhs1
) == INTEGER_CST
)
2755 rhs1
= fold_convert (type1
, rhs1
);
2756 if (TREE_CODE (rhs2
) == INTEGER_CST
)
2757 rhs2
= fold_convert (type2
, rhs2
);
2759 gimple_assign_set_rhs1 (stmt
, rhs1
);
2760 gimple_assign_set_rhs2 (stmt
, rhs2
);
2761 gimple_assign_set_rhs_code (stmt
, WIDEN_MULT_EXPR
);
2763 widen_mul_stats
.widen_mults_inserted
++;
2767 /* Process a single gimple statement STMT, which is found at the
2768 iterator GSI and has a either a PLUS_EXPR or a MINUS_EXPR as its
2769 rhs (given by CODE), and try to convert it into a
2770 WIDEN_MULT_PLUS_EXPR or a WIDEN_MULT_MINUS_EXPR. The return value
2771 is true iff we converted the statement. */
2774 convert_plusminus_to_widen (gimple_stmt_iterator
*gsi
, gimple stmt
,
2775 enum tree_code code
)
2777 gimple rhs1_stmt
= NULL
, rhs2_stmt
= NULL
;
2778 gimple conv1_stmt
= NULL
, conv2_stmt
= NULL
, conv_stmt
;
2779 tree type
, type1
, type2
, optype
;
2780 tree lhs
, rhs1
, rhs2
, mult_rhs1
, mult_rhs2
, add_rhs
;
2781 enum tree_code rhs1_code
= ERROR_MARK
, rhs2_code
= ERROR_MARK
;
2783 enum tree_code wmult_code
;
2784 enum insn_code handler
;
2785 machine_mode to_mode
, from_mode
, actual_mode
;
2786 location_t loc
= gimple_location (stmt
);
2787 int actual_precision
;
2788 bool from_unsigned1
, from_unsigned2
;
2790 lhs
= gimple_assign_lhs (stmt
);
2791 type
= TREE_TYPE (lhs
);
2792 if (TREE_CODE (type
) != INTEGER_TYPE
2793 && TREE_CODE (type
) != FIXED_POINT_TYPE
)
2796 if (code
== MINUS_EXPR
)
2797 wmult_code
= WIDEN_MULT_MINUS_EXPR
;
2799 wmult_code
= WIDEN_MULT_PLUS_EXPR
;
2801 rhs1
= gimple_assign_rhs1 (stmt
);
2802 rhs2
= gimple_assign_rhs2 (stmt
);
2804 if (TREE_CODE (rhs1
) == SSA_NAME
)
2806 rhs1_stmt
= SSA_NAME_DEF_STMT (rhs1
);
2807 if (is_gimple_assign (rhs1_stmt
))
2808 rhs1_code
= gimple_assign_rhs_code (rhs1_stmt
);
2811 if (TREE_CODE (rhs2
) == SSA_NAME
)
2813 rhs2_stmt
= SSA_NAME_DEF_STMT (rhs2
);
2814 if (is_gimple_assign (rhs2_stmt
))
2815 rhs2_code
= gimple_assign_rhs_code (rhs2_stmt
);
2818 /* Allow for one conversion statement between the multiply
2819 and addition/subtraction statement. If there are more than
2820 one conversions then we assume they would invalidate this
2821 transformation. If that's not the case then they should have
2822 been folded before now. */
2823 if (CONVERT_EXPR_CODE_P (rhs1_code
))
2825 conv1_stmt
= rhs1_stmt
;
2826 rhs1
= gimple_assign_rhs1 (rhs1_stmt
);
2827 if (TREE_CODE (rhs1
) == SSA_NAME
)
2829 rhs1_stmt
= SSA_NAME_DEF_STMT (rhs1
);
2830 if (is_gimple_assign (rhs1_stmt
))
2831 rhs1_code
= gimple_assign_rhs_code (rhs1_stmt
);
2836 if (CONVERT_EXPR_CODE_P (rhs2_code
))
2838 conv2_stmt
= rhs2_stmt
;
2839 rhs2
= gimple_assign_rhs1 (rhs2_stmt
);
2840 if (TREE_CODE (rhs2
) == SSA_NAME
)
2842 rhs2_stmt
= SSA_NAME_DEF_STMT (rhs2
);
2843 if (is_gimple_assign (rhs2_stmt
))
2844 rhs2_code
= gimple_assign_rhs_code (rhs2_stmt
);
2850 /* If code is WIDEN_MULT_EXPR then it would seem unnecessary to call
2851 is_widening_mult_p, but we still need the rhs returns.
2853 It might also appear that it would be sufficient to use the existing
2854 operands of the widening multiply, but that would limit the choice of
2855 multiply-and-accumulate instructions.
2857 If the widened-multiplication result has more than one uses, it is
2858 probably wiser not to do the conversion. */
2859 if (code
== PLUS_EXPR
2860 && (rhs1_code
== MULT_EXPR
|| rhs1_code
== WIDEN_MULT_EXPR
))
2862 if (!has_single_use (rhs1
)
2863 || !is_widening_mult_p (rhs1_stmt
, &type1
, &mult_rhs1
,
2864 &type2
, &mult_rhs2
))
2867 conv_stmt
= conv1_stmt
;
2869 else if (rhs2_code
== MULT_EXPR
|| rhs2_code
== WIDEN_MULT_EXPR
)
2871 if (!has_single_use (rhs2
)
2872 || !is_widening_mult_p (rhs2_stmt
, &type1
, &mult_rhs1
,
2873 &type2
, &mult_rhs2
))
2876 conv_stmt
= conv2_stmt
;
2881 to_mode
= TYPE_MODE (type
);
2882 from_mode
= TYPE_MODE (type1
);
2883 from_unsigned1
= TYPE_UNSIGNED (type1
);
2884 from_unsigned2
= TYPE_UNSIGNED (type2
);
2887 /* There's no such thing as a mixed sign madd yet, so use a wider mode. */
2888 if (from_unsigned1
!= from_unsigned2
)
2890 if (!INTEGRAL_TYPE_P (type
))
2892 /* We can use a signed multiply with unsigned types as long as
2893 there is a wider mode to use, or it is the smaller of the two
2894 types that is unsigned. Note that type1 >= type2, always. */
2896 && TYPE_PRECISION (type1
) == GET_MODE_PRECISION (from_mode
))
2898 && TYPE_PRECISION (type2
) == GET_MODE_PRECISION (from_mode
)))
2900 from_mode
= GET_MODE_WIDER_MODE (from_mode
);
2901 if (GET_MODE_SIZE (from_mode
) >= GET_MODE_SIZE (to_mode
))
2905 from_unsigned1
= from_unsigned2
= false;
2906 optype
= build_nonstandard_integer_type (GET_MODE_PRECISION (from_mode
),
2910 /* If there was a conversion between the multiply and addition
2911 then we need to make sure it fits a multiply-and-accumulate.
2912 The should be a single mode change which does not change the
2916 /* We use the original, unmodified data types for this. */
2917 tree from_type
= TREE_TYPE (gimple_assign_rhs1 (conv_stmt
));
2918 tree to_type
= TREE_TYPE (gimple_assign_lhs (conv_stmt
));
2919 int data_size
= TYPE_PRECISION (type1
) + TYPE_PRECISION (type2
);
2920 bool is_unsigned
= TYPE_UNSIGNED (type1
) && TYPE_UNSIGNED (type2
);
2922 if (TYPE_PRECISION (from_type
) > TYPE_PRECISION (to_type
))
2924 /* Conversion is a truncate. */
2925 if (TYPE_PRECISION (to_type
) < data_size
)
2928 else if (TYPE_PRECISION (from_type
) < TYPE_PRECISION (to_type
))
2930 /* Conversion is an extend. Check it's the right sort. */
2931 if (TYPE_UNSIGNED (from_type
) != is_unsigned
2932 && !(is_unsigned
&& TYPE_PRECISION (from_type
) > data_size
))
2935 /* else convert is a no-op for our purposes. */
2938 /* Verify that the machine can perform a widening multiply
2939 accumulate in this mode/signedness combination, otherwise
2940 this transformation is likely to pessimize code. */
2941 this_optab
= optab_for_tree_code (wmult_code
, optype
, optab_default
);
2942 handler
= find_widening_optab_handler_and_mode (this_optab
, to_mode
,
2943 from_mode
, 0, &actual_mode
);
2945 if (handler
== CODE_FOR_nothing
)
2948 /* Ensure that the inputs to the handler are in the correct precison
2949 for the opcode. This will be the full mode size. */
2950 actual_precision
= GET_MODE_PRECISION (actual_mode
);
2951 if (actual_precision
!= TYPE_PRECISION (type1
)
2952 || from_unsigned1
!= TYPE_UNSIGNED (type1
))
2953 mult_rhs1
= build_and_insert_cast (gsi
, loc
,
2954 build_nonstandard_integer_type
2955 (actual_precision
, from_unsigned1
),
2957 if (actual_precision
!= TYPE_PRECISION (type2
)
2958 || from_unsigned2
!= TYPE_UNSIGNED (type2
))
2959 mult_rhs2
= build_and_insert_cast (gsi
, loc
,
2960 build_nonstandard_integer_type
2961 (actual_precision
, from_unsigned2
),
2964 if (!useless_type_conversion_p (type
, TREE_TYPE (add_rhs
)))
2965 add_rhs
= build_and_insert_cast (gsi
, loc
, type
, add_rhs
);
2967 /* Handle constants. */
2968 if (TREE_CODE (mult_rhs1
) == INTEGER_CST
)
2969 mult_rhs1
= fold_convert (type1
, mult_rhs1
);
2970 if (TREE_CODE (mult_rhs2
) == INTEGER_CST
)
2971 mult_rhs2
= fold_convert (type2
, mult_rhs2
);
2973 gimple_assign_set_rhs_with_ops (gsi
, wmult_code
, mult_rhs1
, mult_rhs2
,
2975 update_stmt (gsi_stmt (*gsi
));
2976 widen_mul_stats
.maccs_inserted
++;
2980 /* Combine the multiplication at MUL_STMT with operands MULOP1 and MULOP2
2981 with uses in additions and subtractions to form fused multiply-add
2982 operations. Returns true if successful and MUL_STMT should be removed. */
2985 convert_mult_to_fma (gimple mul_stmt
, tree op1
, tree op2
)
2987 tree mul_result
= gimple_get_lhs (mul_stmt
);
2988 tree type
= TREE_TYPE (mul_result
);
2989 gimple use_stmt
, neguse_stmt
, fma_stmt
;
2990 use_operand_p use_p
;
2991 imm_use_iterator imm_iter
;
2993 if (FLOAT_TYPE_P (type
)
2994 && flag_fp_contract_mode
== FP_CONTRACT_OFF
)
2997 /* We don't want to do bitfield reduction ops. */
2998 if (INTEGRAL_TYPE_P (type
)
2999 && (TYPE_PRECISION (type
)
3000 != GET_MODE_PRECISION (TYPE_MODE (type
))))
3003 /* If the target doesn't support it, don't generate it. We assume that
3004 if fma isn't available then fms, fnma or fnms are not either. */
3005 if (optab_handler (fma_optab
, TYPE_MODE (type
)) == CODE_FOR_nothing
)
3008 /* If the multiplication has zero uses, it is kept around probably because
3009 of -fnon-call-exceptions. Don't optimize it away in that case,
3011 if (has_zero_uses (mul_result
))
3014 /* Make sure that the multiplication statement becomes dead after
3015 the transformation, thus that all uses are transformed to FMAs.
3016 This means we assume that an FMA operation has the same cost
3018 FOR_EACH_IMM_USE_FAST (use_p
, imm_iter
, mul_result
)
3020 enum tree_code use_code
;
3021 tree result
= mul_result
;
3022 bool negate_p
= false;
3024 use_stmt
= USE_STMT (use_p
);
3026 if (is_gimple_debug (use_stmt
))
3029 /* For now restrict this operations to single basic blocks. In theory
3030 we would want to support sinking the multiplication in
3036 to form a fma in the then block and sink the multiplication to the
3038 if (gimple_bb (use_stmt
) != gimple_bb (mul_stmt
))
3041 if (!is_gimple_assign (use_stmt
))
3044 use_code
= gimple_assign_rhs_code (use_stmt
);
3046 /* A negate on the multiplication leads to FNMA. */
3047 if (use_code
== NEGATE_EXPR
)
3052 result
= gimple_assign_lhs (use_stmt
);
3054 /* Make sure the negate statement becomes dead with this
3055 single transformation. */
3056 if (!single_imm_use (gimple_assign_lhs (use_stmt
),
3057 &use_p
, &neguse_stmt
))
3060 /* Make sure the multiplication isn't also used on that stmt. */
3061 FOR_EACH_PHI_OR_STMT_USE (usep
, neguse_stmt
, iter
, SSA_OP_USE
)
3062 if (USE_FROM_PTR (usep
) == mul_result
)
3066 use_stmt
= neguse_stmt
;
3067 if (gimple_bb (use_stmt
) != gimple_bb (mul_stmt
))
3069 if (!is_gimple_assign (use_stmt
))
3072 use_code
= gimple_assign_rhs_code (use_stmt
);
3079 if (gimple_assign_rhs2 (use_stmt
) == result
)
3080 negate_p
= !negate_p
;
3085 /* FMA can only be formed from PLUS and MINUS. */
3089 /* If the subtrahend (gimple_assign_rhs2 (use_stmt)) is computed
3090 by a MULT_EXPR that we'll visit later, we might be able to
3091 get a more profitable match with fnma.
3092 OTOH, if we don't, a negate / fma pair has likely lower latency
3093 that a mult / subtract pair. */
3094 if (use_code
== MINUS_EXPR
&& !negate_p
3095 && gimple_assign_rhs1 (use_stmt
) == result
3096 && optab_handler (fms_optab
, TYPE_MODE (type
)) == CODE_FOR_nothing
3097 && optab_handler (fnma_optab
, TYPE_MODE (type
)) != CODE_FOR_nothing
)
3099 tree rhs2
= gimple_assign_rhs2 (use_stmt
);
3101 if (TREE_CODE (rhs2
) == SSA_NAME
)
3103 gimple stmt2
= SSA_NAME_DEF_STMT (rhs2
);
3104 if (has_single_use (rhs2
)
3105 && is_gimple_assign (stmt2
)
3106 && gimple_assign_rhs_code (stmt2
) == MULT_EXPR
)
3111 /* We can't handle a * b + a * b. */
3112 if (gimple_assign_rhs1 (use_stmt
) == gimple_assign_rhs2 (use_stmt
))
3115 /* While it is possible to validate whether or not the exact form
3116 that we've recognized is available in the backend, the assumption
3117 is that the transformation is never a loss. For instance, suppose
3118 the target only has the plain FMA pattern available. Consider
3119 a*b-c -> fma(a,b,-c): we've exchanged MUL+SUB for FMA+NEG, which
3120 is still two operations. Consider -(a*b)-c -> fma(-a,b,-c): we
3121 still have 3 operations, but in the FMA form the two NEGs are
3122 independent and could be run in parallel. */
3125 FOR_EACH_IMM_USE_STMT (use_stmt
, imm_iter
, mul_result
)
3127 gimple_stmt_iterator gsi
= gsi_for_stmt (use_stmt
);
3128 enum tree_code use_code
;
3129 tree addop
, mulop1
= op1
, result
= mul_result
;
3130 bool negate_p
= false;
3132 if (is_gimple_debug (use_stmt
))
3135 use_code
= gimple_assign_rhs_code (use_stmt
);
3136 if (use_code
== NEGATE_EXPR
)
3138 result
= gimple_assign_lhs (use_stmt
);
3139 single_imm_use (gimple_assign_lhs (use_stmt
), &use_p
, &neguse_stmt
);
3140 gsi_remove (&gsi
, true);
3141 release_defs (use_stmt
);
3143 use_stmt
= neguse_stmt
;
3144 gsi
= gsi_for_stmt (use_stmt
);
3145 use_code
= gimple_assign_rhs_code (use_stmt
);
3149 if (gimple_assign_rhs1 (use_stmt
) == result
)
3151 addop
= gimple_assign_rhs2 (use_stmt
);
3152 /* a * b - c -> a * b + (-c) */
3153 if (gimple_assign_rhs_code (use_stmt
) == MINUS_EXPR
)
3154 addop
= force_gimple_operand_gsi (&gsi
,
3155 build1 (NEGATE_EXPR
,
3157 true, NULL_TREE
, true,
3162 addop
= gimple_assign_rhs1 (use_stmt
);
3163 /* a - b * c -> (-b) * c + a */
3164 if (gimple_assign_rhs_code (use_stmt
) == MINUS_EXPR
)
3165 negate_p
= !negate_p
;
3169 mulop1
= force_gimple_operand_gsi (&gsi
,
3170 build1 (NEGATE_EXPR
,
3172 true, NULL_TREE
, true,
3175 fma_stmt
= gimple_build_assign_with_ops (FMA_EXPR
,
3176 gimple_assign_lhs (use_stmt
),
3177 mulop1
, op2
, addop
);
3178 gsi_replace (&gsi
, fma_stmt
, true);
3179 widen_mul_stats
.fmas_inserted
++;
3185 /* Find integer multiplications where the operands are extended from
3186 smaller types, and replace the MULT_EXPR with a WIDEN_MULT_EXPR
3187 where appropriate. */
3191 const pass_data pass_data_optimize_widening_mul
=
3193 GIMPLE_PASS
, /* type */
3194 "widening_mul", /* name */
3195 OPTGROUP_NONE
, /* optinfo_flags */
3196 TV_NONE
, /* tv_id */
3197 PROP_ssa
, /* properties_required */
3198 0, /* properties_provided */
3199 0, /* properties_destroyed */
3200 0, /* todo_flags_start */
3201 TODO_update_ssa
, /* todo_flags_finish */
3204 class pass_optimize_widening_mul
: public gimple_opt_pass
3207 pass_optimize_widening_mul (gcc::context
*ctxt
)
3208 : gimple_opt_pass (pass_data_optimize_widening_mul
, ctxt
)
3211 /* opt_pass methods: */
3212 virtual bool gate (function
*)
3214 return flag_expensive_optimizations
&& optimize
;
3217 virtual unsigned int execute (function
*);
3219 }; // class pass_optimize_widening_mul
3222 pass_optimize_widening_mul::execute (function
*fun
)
3225 bool cfg_changed
= false;
3227 memset (&widen_mul_stats
, 0, sizeof (widen_mul_stats
));
3229 FOR_EACH_BB_FN (bb
, fun
)
3231 gimple_stmt_iterator gsi
;
3233 for (gsi
= gsi_after_labels (bb
); !gsi_end_p (gsi
);)
3235 gimple stmt
= gsi_stmt (gsi
);
3236 enum tree_code code
;
3238 if (is_gimple_assign (stmt
))
3240 code
= gimple_assign_rhs_code (stmt
);
3244 if (!convert_mult_to_widen (stmt
, &gsi
)
3245 && convert_mult_to_fma (stmt
,
3246 gimple_assign_rhs1 (stmt
),
3247 gimple_assign_rhs2 (stmt
)))
3249 gsi_remove (&gsi
, true);
3250 release_defs (stmt
);
3257 convert_plusminus_to_widen (&gsi
, stmt
, code
);
3263 else if (is_gimple_call (stmt
)
3264 && gimple_call_lhs (stmt
))
3266 tree fndecl
= gimple_call_fndecl (stmt
);
3268 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
3270 switch (DECL_FUNCTION_CODE (fndecl
))
3275 if (TREE_CODE (gimple_call_arg (stmt
, 1)) == REAL_CST
3276 && REAL_VALUES_EQUAL
3277 (TREE_REAL_CST (gimple_call_arg (stmt
, 1)),
3279 && convert_mult_to_fma (stmt
,
3280 gimple_call_arg (stmt
, 0),
3281 gimple_call_arg (stmt
, 0)))
3283 unlink_stmt_vdef (stmt
);
3284 if (gsi_remove (&gsi
, true)
3285 && gimple_purge_dead_eh_edges (bb
))
3287 release_defs (stmt
);
3300 statistics_counter_event (fun
, "widening multiplications inserted",
3301 widen_mul_stats
.widen_mults_inserted
);
3302 statistics_counter_event (fun
, "widening maccs inserted",
3303 widen_mul_stats
.maccs_inserted
);
3304 statistics_counter_event (fun
, "fused multiply-adds inserted",
3305 widen_mul_stats
.fmas_inserted
);
3307 return cfg_changed
? TODO_cleanup_cfg
: 0;
3313 make_pass_optimize_widening_mul (gcc::context
*ctxt
)
3315 return new pass_optimize_widening_mul (ctxt
);