1 /* Global, SSA-based optimizations using mathematical identities.
2 Copyright (C) 2005-2016 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 by 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"
96 #include "alloc-pool.h"
97 #include "tree-pass.h"
99 #include "optabs-tree.h"
100 #include "gimple-pretty-print.h"
102 #include "fold-const.h"
103 #include "gimple-fold.h"
104 #include "gimple-iterator.h"
105 #include "gimplify.h"
106 #include "gimplify-me.h"
107 #include "stor-layout.h"
108 #include "tree-cfg.h"
109 #include "tree-dfa.h"
110 #include "tree-ssa.h"
111 #include "builtins.h"
113 #include "internal-fn.h"
114 #include "case-cfn-macros.h"
115 #include "optabs-libfuncs.h"
117 #include "targhooks.h"
119 /* This structure represents one basic block that either computes a
120 division, or is a common dominator for basic block that compute a
123 /* The basic block represented by this structure. */
126 /* If non-NULL, the SSA_NAME holding the definition for a reciprocal
130 /* If non-NULL, the GIMPLE_ASSIGN for a reciprocal computation that
131 was inserted in BB. */
132 gimple
*recip_def_stmt
;
134 /* Pointer to a list of "struct occurrence"s for blocks dominated
136 struct occurrence
*children
;
138 /* Pointer to the next "struct occurrence"s in the list of blocks
139 sharing a common dominator. */
140 struct occurrence
*next
;
142 /* The number of divisions that are in BB before compute_merit. The
143 number of divisions that are in BB or post-dominate it after
147 /* True if the basic block has a division, false if it is a common
148 dominator for basic blocks that do. If it is false and trapping
149 math is active, BB is not a candidate for inserting a reciprocal. */
150 bool bb_has_division
;
155 /* Number of 1.0/X ops inserted. */
158 /* Number of 1.0/FUNC ops inserted. */
164 /* Number of cexpi calls inserted. */
170 /* Number of hand-written 16-bit nop / bswaps found. */
173 /* Number of hand-written 32-bit nop / bswaps found. */
176 /* Number of hand-written 64-bit nop / bswaps found. */
178 } nop_stats
, bswap_stats
;
182 /* Number of widening multiplication ops inserted. */
183 int widen_mults_inserted
;
185 /* Number of integer multiply-and-accumulate ops inserted. */
188 /* Number of fp fused multiply-add ops inserted. */
191 /* Number of divmod calls inserted. */
192 int divmod_calls_inserted
;
195 /* The instance of "struct occurrence" representing the highest
196 interesting block in the dominator tree. */
197 static struct occurrence
*occ_head
;
199 /* Allocation pool for getting instances of "struct occurrence". */
200 static object_allocator
<occurrence
> *occ_pool
;
204 /* Allocate and return a new struct occurrence for basic block BB, and
205 whose children list is headed by CHILDREN. */
206 static struct occurrence
*
207 occ_new (basic_block bb
, struct occurrence
*children
)
209 struct occurrence
*occ
;
211 bb
->aux
= occ
= occ_pool
->allocate ();
212 memset (occ
, 0, sizeof (struct occurrence
));
215 occ
->children
= children
;
220 /* Insert NEW_OCC into our subset of the dominator tree. P_HEAD points to a
221 list of "struct occurrence"s, one per basic block, having IDOM as
222 their common dominator.
224 We try to insert NEW_OCC as deep as possible in the tree, and we also
225 insert any other block that is a common dominator for BB and one
226 block already in the tree. */
229 insert_bb (struct occurrence
*new_occ
, basic_block idom
,
230 struct occurrence
**p_head
)
232 struct occurrence
*occ
, **p_occ
;
234 for (p_occ
= p_head
; (occ
= *p_occ
) != NULL
; )
236 basic_block bb
= new_occ
->bb
, occ_bb
= occ
->bb
;
237 basic_block dom
= nearest_common_dominator (CDI_DOMINATORS
, occ_bb
, bb
);
240 /* BB dominates OCC_BB. OCC becomes NEW_OCC's child: remove OCC
243 occ
->next
= new_occ
->children
;
244 new_occ
->children
= occ
;
246 /* Try the next block (it may as well be dominated by BB). */
249 else if (dom
== occ_bb
)
251 /* OCC_BB dominates BB. Tail recurse to look deeper. */
252 insert_bb (new_occ
, dom
, &occ
->children
);
256 else if (dom
!= idom
)
258 gcc_assert (!dom
->aux
);
260 /* There is a dominator between IDOM and BB, add it and make
261 two children out of NEW_OCC and OCC. First, remove OCC from
267 /* None of the previous blocks has DOM as a dominator: if we tail
268 recursed, we would reexamine them uselessly. Just switch BB with
269 DOM, and go on looking for blocks dominated by DOM. */
270 new_occ
= occ_new (dom
, new_occ
);
275 /* Nothing special, go on with the next element. */
280 /* No place was found as a child of IDOM. Make BB a sibling of IDOM. */
281 new_occ
->next
= *p_head
;
285 /* Register that we found a division in BB. */
288 register_division_in (basic_block bb
)
290 struct occurrence
*occ
;
292 occ
= (struct occurrence
*) bb
->aux
;
295 occ
= occ_new (bb
, NULL
);
296 insert_bb (occ
, ENTRY_BLOCK_PTR_FOR_FN (cfun
), &occ_head
);
299 occ
->bb_has_division
= true;
300 occ
->num_divisions
++;
304 /* Compute the number of divisions that postdominate each block in OCC and
308 compute_merit (struct occurrence
*occ
)
310 struct occurrence
*occ_child
;
311 basic_block dom
= occ
->bb
;
313 for (occ_child
= occ
->children
; occ_child
; occ_child
= occ_child
->next
)
316 if (occ_child
->children
)
317 compute_merit (occ_child
);
320 bb
= single_noncomplex_succ (dom
);
324 if (dominated_by_p (CDI_POST_DOMINATORS
, bb
, occ_child
->bb
))
325 occ
->num_divisions
+= occ_child
->num_divisions
;
330 /* Return whether USE_STMT is a floating-point division by DEF. */
332 is_division_by (gimple
*use_stmt
, tree def
)
334 return is_gimple_assign (use_stmt
)
335 && gimple_assign_rhs_code (use_stmt
) == RDIV_EXPR
336 && gimple_assign_rhs2 (use_stmt
) == def
337 /* Do not recognize x / x as valid division, as we are getting
338 confused later by replacing all immediate uses x in such
340 && gimple_assign_rhs1 (use_stmt
) != def
;
343 /* Walk the subset of the dominator tree rooted at OCC, setting the
344 RECIP_DEF field to a definition of 1.0 / DEF that can be used in
345 the given basic block. The field may be left NULL, of course,
346 if it is not possible or profitable to do the optimization.
348 DEF_BSI is an iterator pointing at the statement defining DEF.
349 If RECIP_DEF is set, a dominator already has a computation that can
353 insert_reciprocals (gimple_stmt_iterator
*def_gsi
, struct occurrence
*occ
,
354 tree def
, tree recip_def
, int threshold
)
358 gimple_stmt_iterator gsi
;
359 struct occurrence
*occ_child
;
362 && (occ
->bb_has_division
|| !flag_trapping_math
)
363 && occ
->num_divisions
>= threshold
)
365 /* Make a variable with the replacement and substitute it. */
366 type
= TREE_TYPE (def
);
367 recip_def
= create_tmp_reg (type
, "reciptmp");
368 new_stmt
= gimple_build_assign (recip_def
, RDIV_EXPR
,
369 build_one_cst (type
), def
);
371 if (occ
->bb_has_division
)
373 /* Case 1: insert before an existing division. */
374 gsi
= gsi_after_labels (occ
->bb
);
375 while (!gsi_end_p (gsi
) && !is_division_by (gsi_stmt (gsi
), def
))
378 gsi_insert_before (&gsi
, new_stmt
, GSI_SAME_STMT
);
380 else if (def_gsi
&& occ
->bb
== def_gsi
->bb
)
382 /* Case 2: insert right after the definition. Note that this will
383 never happen if the definition statement can throw, because in
384 that case the sole successor of the statement's basic block will
385 dominate all the uses as well. */
386 gsi_insert_after (def_gsi
, new_stmt
, GSI_NEW_STMT
);
390 /* Case 3: insert in a basic block not containing defs/uses. */
391 gsi
= gsi_after_labels (occ
->bb
);
392 gsi_insert_before (&gsi
, new_stmt
, GSI_SAME_STMT
);
395 reciprocal_stats
.rdivs_inserted
++;
397 occ
->recip_def_stmt
= new_stmt
;
400 occ
->recip_def
= recip_def
;
401 for (occ_child
= occ
->children
; occ_child
; occ_child
= occ_child
->next
)
402 insert_reciprocals (def_gsi
, occ_child
, def
, recip_def
, threshold
);
406 /* Replace the division at USE_P with a multiplication by the reciprocal, if
410 replace_reciprocal (use_operand_p use_p
)
412 gimple
*use_stmt
= USE_STMT (use_p
);
413 basic_block bb
= gimple_bb (use_stmt
);
414 struct occurrence
*occ
= (struct occurrence
*) bb
->aux
;
416 if (optimize_bb_for_speed_p (bb
)
417 && occ
->recip_def
&& use_stmt
!= occ
->recip_def_stmt
)
419 gimple_stmt_iterator gsi
= gsi_for_stmt (use_stmt
);
420 gimple_assign_set_rhs_code (use_stmt
, MULT_EXPR
);
421 SET_USE (use_p
, occ
->recip_def
);
422 fold_stmt_inplace (&gsi
);
423 update_stmt (use_stmt
);
428 /* Free OCC and return one more "struct occurrence" to be freed. */
430 static struct occurrence
*
431 free_bb (struct occurrence
*occ
)
433 struct occurrence
*child
, *next
;
435 /* First get the two pointers hanging off OCC. */
437 child
= occ
->children
;
439 occ_pool
->remove (occ
);
441 /* Now ensure that we don't recurse unless it is necessary. */
447 next
= free_bb (next
);
454 /* Look for floating-point divisions among DEF's uses, and try to
455 replace them by multiplications with the reciprocal. Add
456 as many statements computing the reciprocal as needed.
458 DEF must be a GIMPLE register of a floating-point type. */
461 execute_cse_reciprocals_1 (gimple_stmt_iterator
*def_gsi
, tree def
)
464 imm_use_iterator use_iter
;
465 struct occurrence
*occ
;
466 int count
= 0, threshold
;
468 gcc_assert (FLOAT_TYPE_P (TREE_TYPE (def
)) && is_gimple_reg (def
));
470 FOR_EACH_IMM_USE_FAST (use_p
, use_iter
, def
)
472 gimple
*use_stmt
= USE_STMT (use_p
);
473 if (is_division_by (use_stmt
, def
))
475 register_division_in (gimple_bb (use_stmt
));
480 /* Do the expensive part only if we can hope to optimize something. */
481 threshold
= targetm
.min_divisions_for_recip_mul (TYPE_MODE (TREE_TYPE (def
)));
482 if (count
>= threshold
)
485 for (occ
= occ_head
; occ
; occ
= occ
->next
)
488 insert_reciprocals (def_gsi
, occ
, def
, NULL
, threshold
);
491 FOR_EACH_IMM_USE_STMT (use_stmt
, use_iter
, def
)
493 if (is_division_by (use_stmt
, def
))
495 FOR_EACH_IMM_USE_ON_STMT (use_p
, use_iter
)
496 replace_reciprocal (use_p
);
501 for (occ
= occ_head
; occ
; )
507 /* Return an internal function that implements the reciprocal of CALL,
508 or IFN_LAST if there is no such function that the target supports. */
511 internal_fn_reciprocal (gcall
*call
)
515 switch (gimple_call_combined_fn (call
))
525 tree_pair types
= direct_internal_fn_types (ifn
, call
);
526 if (!direct_internal_fn_supported_p (ifn
, types
, OPTIMIZE_FOR_SPEED
))
532 /* Go through all the floating-point SSA_NAMEs, and call
533 execute_cse_reciprocals_1 on each of them. */
536 const pass_data pass_data_cse_reciprocals
=
538 GIMPLE_PASS
, /* type */
540 OPTGROUP_NONE
, /* optinfo_flags */
542 PROP_ssa
, /* properties_required */
543 0, /* properties_provided */
544 0, /* properties_destroyed */
545 0, /* todo_flags_start */
546 TODO_update_ssa
, /* todo_flags_finish */
549 class pass_cse_reciprocals
: public gimple_opt_pass
552 pass_cse_reciprocals (gcc::context
*ctxt
)
553 : gimple_opt_pass (pass_data_cse_reciprocals
, ctxt
)
556 /* opt_pass methods: */
557 virtual bool gate (function
*) { return optimize
&& flag_reciprocal_math
; }
558 virtual unsigned int execute (function
*);
560 }; // class pass_cse_reciprocals
563 pass_cse_reciprocals::execute (function
*fun
)
568 occ_pool
= new object_allocator
<occurrence
> ("dominators for recip");
570 memset (&reciprocal_stats
, 0, sizeof (reciprocal_stats
));
571 calculate_dominance_info (CDI_DOMINATORS
);
572 calculate_dominance_info (CDI_POST_DOMINATORS
);
575 FOR_EACH_BB_FN (bb
, fun
)
576 gcc_assert (!bb
->aux
);
578 for (arg
= DECL_ARGUMENTS (fun
->decl
); arg
; arg
= DECL_CHAIN (arg
))
579 if (FLOAT_TYPE_P (TREE_TYPE (arg
))
580 && is_gimple_reg (arg
))
582 tree name
= ssa_default_def (fun
, arg
);
584 execute_cse_reciprocals_1 (NULL
, name
);
587 FOR_EACH_BB_FN (bb
, fun
)
591 for (gphi_iterator gsi
= gsi_start_phis (bb
); !gsi_end_p (gsi
);
594 gphi
*phi
= gsi
.phi ();
595 def
= PHI_RESULT (phi
);
596 if (! virtual_operand_p (def
)
597 && FLOAT_TYPE_P (TREE_TYPE (def
)))
598 execute_cse_reciprocals_1 (NULL
, def
);
601 for (gimple_stmt_iterator gsi
= gsi_after_labels (bb
); !gsi_end_p (gsi
);
604 gimple
*stmt
= gsi_stmt (gsi
);
606 if (gimple_has_lhs (stmt
)
607 && (def
= SINGLE_SSA_TREE_OPERAND (stmt
, SSA_OP_DEF
)) != NULL
608 && FLOAT_TYPE_P (TREE_TYPE (def
))
609 && TREE_CODE (def
) == SSA_NAME
)
610 execute_cse_reciprocals_1 (&gsi
, def
);
613 if (optimize_bb_for_size_p (bb
))
616 /* Scan for a/func(b) and convert it to reciprocal a*rfunc(b). */
617 for (gimple_stmt_iterator gsi
= gsi_after_labels (bb
); !gsi_end_p (gsi
);
620 gimple
*stmt
= gsi_stmt (gsi
);
622 if (is_gimple_assign (stmt
)
623 && gimple_assign_rhs_code (stmt
) == RDIV_EXPR
)
625 tree arg1
= gimple_assign_rhs2 (stmt
);
628 if (TREE_CODE (arg1
) != SSA_NAME
)
631 stmt1
= SSA_NAME_DEF_STMT (arg1
);
633 if (is_gimple_call (stmt1
)
634 && gimple_call_lhs (stmt1
))
639 tree fndecl
= NULL_TREE
;
641 gcall
*call
= as_a
<gcall
*> (stmt1
);
642 internal_fn ifn
= internal_fn_reciprocal (call
);
645 fndecl
= gimple_call_fndecl (call
);
647 || DECL_BUILT_IN_CLASS (fndecl
) != BUILT_IN_MD
)
649 fndecl
= targetm
.builtin_reciprocal (fndecl
);
654 /* Check that all uses of the SSA name are divisions,
655 otherwise replacing the defining statement will do
658 FOR_EACH_IMM_USE_FAST (use_p
, ui
, arg1
)
660 gimple
*stmt2
= USE_STMT (use_p
);
661 if (is_gimple_debug (stmt2
))
663 if (!is_gimple_assign (stmt2
)
664 || gimple_assign_rhs_code (stmt2
) != RDIV_EXPR
665 || gimple_assign_rhs1 (stmt2
) == arg1
666 || gimple_assign_rhs2 (stmt2
) != arg1
)
675 gimple_replace_ssa_lhs (call
, arg1
);
676 if (gimple_call_internal_p (call
) != (ifn
!= IFN_LAST
))
678 auto_vec
<tree
, 4> args
;
679 for (unsigned int i
= 0;
680 i
< gimple_call_num_args (call
); i
++)
681 args
.safe_push (gimple_call_arg (call
, i
));
684 stmt2
= gimple_build_call_vec (fndecl
, args
);
686 stmt2
= gimple_build_call_internal_vec (ifn
, args
);
687 gimple_call_set_lhs (stmt2
, arg1
);
688 if (gimple_vdef (call
))
690 gimple_set_vdef (stmt2
, gimple_vdef (call
));
691 SSA_NAME_DEF_STMT (gimple_vdef (stmt2
)) = stmt2
;
693 gimple_set_vuse (stmt2
, gimple_vuse (call
));
694 gimple_stmt_iterator gsi2
= gsi_for_stmt (call
);
695 gsi_replace (&gsi2
, stmt2
, true);
700 gimple_call_set_fndecl (call
, fndecl
);
702 gimple_call_set_internal_fn (call
, ifn
);
705 reciprocal_stats
.rfuncs_inserted
++;
707 FOR_EACH_IMM_USE_STMT (stmt
, ui
, arg1
)
709 gimple_stmt_iterator gsi
= gsi_for_stmt (stmt
);
710 gimple_assign_set_rhs_code (stmt
, MULT_EXPR
);
711 fold_stmt_inplace (&gsi
);
719 statistics_counter_event (fun
, "reciprocal divs inserted",
720 reciprocal_stats
.rdivs_inserted
);
721 statistics_counter_event (fun
, "reciprocal functions inserted",
722 reciprocal_stats
.rfuncs_inserted
);
724 free_dominance_info (CDI_DOMINATORS
);
725 free_dominance_info (CDI_POST_DOMINATORS
);
733 make_pass_cse_reciprocals (gcc::context
*ctxt
)
735 return new pass_cse_reciprocals (ctxt
);
738 /* Records an occurrence at statement USE_STMT in the vector of trees
739 STMTS if it is dominated by *TOP_BB or dominates it or this basic block
740 is not yet initialized. Returns true if the occurrence was pushed on
741 the vector. Adjusts *TOP_BB to be the basic block dominating all
742 statements in the vector. */
745 maybe_record_sincos (vec
<gimple
*> *stmts
,
746 basic_block
*top_bb
, gimple
*use_stmt
)
748 basic_block use_bb
= gimple_bb (use_stmt
);
750 && (*top_bb
== use_bb
751 || dominated_by_p (CDI_DOMINATORS
, use_bb
, *top_bb
)))
752 stmts
->safe_push (use_stmt
);
754 || dominated_by_p (CDI_DOMINATORS
, *top_bb
, use_bb
))
756 stmts
->safe_push (use_stmt
);
765 /* Look for sin, cos and cexpi calls with the same argument NAME and
766 create a single call to cexpi CSEing the result in this case.
767 We first walk over all immediate uses of the argument collecting
768 statements that we can CSE in a vector and in a second pass replace
769 the statement rhs with a REALPART or IMAGPART expression on the
770 result of the cexpi call we insert before the use statement that
771 dominates all other candidates. */
774 execute_cse_sincos_1 (tree name
)
776 gimple_stmt_iterator gsi
;
777 imm_use_iterator use_iter
;
778 tree fndecl
, res
, type
;
779 gimple
*def_stmt
, *use_stmt
, *stmt
;
780 int seen_cos
= 0, seen_sin
= 0, seen_cexpi
= 0;
781 auto_vec
<gimple
*> stmts
;
782 basic_block top_bb
= NULL
;
784 bool cfg_changed
= false;
786 type
= TREE_TYPE (name
);
787 FOR_EACH_IMM_USE_STMT (use_stmt
, use_iter
, name
)
789 if (gimple_code (use_stmt
) != GIMPLE_CALL
790 || !gimple_call_lhs (use_stmt
))
793 switch (gimple_call_combined_fn (use_stmt
))
796 seen_cos
|= maybe_record_sincos (&stmts
, &top_bb
, use_stmt
) ? 1 : 0;
800 seen_sin
|= maybe_record_sincos (&stmts
, &top_bb
, use_stmt
) ? 1 : 0;
804 seen_cexpi
|= maybe_record_sincos (&stmts
, &top_bb
, use_stmt
) ? 1 : 0;
811 if (seen_cos
+ seen_sin
+ seen_cexpi
<= 1)
814 /* Simply insert cexpi at the beginning of top_bb but not earlier than
815 the name def statement. */
816 fndecl
= mathfn_built_in (type
, BUILT_IN_CEXPI
);
819 stmt
= gimple_build_call (fndecl
, 1, name
);
820 res
= make_temp_ssa_name (TREE_TYPE (TREE_TYPE (fndecl
)), stmt
, "sincostmp");
821 gimple_call_set_lhs (stmt
, res
);
823 def_stmt
= SSA_NAME_DEF_STMT (name
);
824 if (!SSA_NAME_IS_DEFAULT_DEF (name
)
825 && gimple_code (def_stmt
) != GIMPLE_PHI
826 && gimple_bb (def_stmt
) == top_bb
)
828 gsi
= gsi_for_stmt (def_stmt
);
829 gsi_insert_after (&gsi
, stmt
, GSI_SAME_STMT
);
833 gsi
= gsi_after_labels (top_bb
);
834 gsi_insert_before (&gsi
, stmt
, GSI_SAME_STMT
);
836 sincos_stats
.inserted
++;
838 /* And adjust the recorded old call sites. */
839 for (i
= 0; stmts
.iterate (i
, &use_stmt
); ++i
)
843 switch (gimple_call_combined_fn (use_stmt
))
846 rhs
= fold_build1 (REALPART_EXPR
, type
, res
);
850 rhs
= fold_build1 (IMAGPART_EXPR
, type
, res
);
861 /* Replace call with a copy. */
862 stmt
= gimple_build_assign (gimple_call_lhs (use_stmt
), rhs
);
864 gsi
= gsi_for_stmt (use_stmt
);
865 gsi_replace (&gsi
, stmt
, true);
866 if (gimple_purge_dead_eh_edges (gimple_bb (stmt
)))
873 /* To evaluate powi(x,n), the floating point value x raised to the
874 constant integer exponent n, we use a hybrid algorithm that
875 combines the "window method" with look-up tables. For an
876 introduction to exponentiation algorithms and "addition chains",
877 see section 4.6.3, "Evaluation of Powers" of Donald E. Knuth,
878 "Seminumerical Algorithms", Vol. 2, "The Art of Computer Programming",
879 3rd Edition, 1998, and Daniel M. Gordon, "A Survey of Fast Exponentiation
880 Methods", Journal of Algorithms, Vol. 27, pp. 129-146, 1998. */
882 /* Provide a default value for POWI_MAX_MULTS, the maximum number of
883 multiplications to inline before calling the system library's pow
884 function. powi(x,n) requires at worst 2*bits(n)-2 multiplications,
885 so this default never requires calling pow, powf or powl. */
887 #ifndef POWI_MAX_MULTS
888 #define POWI_MAX_MULTS (2*HOST_BITS_PER_WIDE_INT-2)
891 /* The size of the "optimal power tree" lookup table. All
892 exponents less than this value are simply looked up in the
893 powi_table below. This threshold is also used to size the
894 cache of pseudo registers that hold intermediate results. */
895 #define POWI_TABLE_SIZE 256
897 /* The size, in bits of the window, used in the "window method"
898 exponentiation algorithm. This is equivalent to a radix of
899 (1<<POWI_WINDOW_SIZE) in the corresponding "m-ary method". */
900 #define POWI_WINDOW_SIZE 3
902 /* The following table is an efficient representation of an
903 "optimal power tree". For each value, i, the corresponding
904 value, j, in the table states than an optimal evaluation
905 sequence for calculating pow(x,i) can be found by evaluating
906 pow(x,j)*pow(x,i-j). An optimal power tree for the first
907 100 integers is given in Knuth's "Seminumerical algorithms". */
909 static const unsigned char powi_table
[POWI_TABLE_SIZE
] =
911 0, 1, 1, 2, 2, 3, 3, 4, /* 0 - 7 */
912 4, 6, 5, 6, 6, 10, 7, 9, /* 8 - 15 */
913 8, 16, 9, 16, 10, 12, 11, 13, /* 16 - 23 */
914 12, 17, 13, 18, 14, 24, 15, 26, /* 24 - 31 */
915 16, 17, 17, 19, 18, 33, 19, 26, /* 32 - 39 */
916 20, 25, 21, 40, 22, 27, 23, 44, /* 40 - 47 */
917 24, 32, 25, 34, 26, 29, 27, 44, /* 48 - 55 */
918 28, 31, 29, 34, 30, 60, 31, 36, /* 56 - 63 */
919 32, 64, 33, 34, 34, 46, 35, 37, /* 64 - 71 */
920 36, 65, 37, 50, 38, 48, 39, 69, /* 72 - 79 */
921 40, 49, 41, 43, 42, 51, 43, 58, /* 80 - 87 */
922 44, 64, 45, 47, 46, 59, 47, 76, /* 88 - 95 */
923 48, 65, 49, 66, 50, 67, 51, 66, /* 96 - 103 */
924 52, 70, 53, 74, 54, 104, 55, 74, /* 104 - 111 */
925 56, 64, 57, 69, 58, 78, 59, 68, /* 112 - 119 */
926 60, 61, 61, 80, 62, 75, 63, 68, /* 120 - 127 */
927 64, 65, 65, 128, 66, 129, 67, 90, /* 128 - 135 */
928 68, 73, 69, 131, 70, 94, 71, 88, /* 136 - 143 */
929 72, 128, 73, 98, 74, 132, 75, 121, /* 144 - 151 */
930 76, 102, 77, 124, 78, 132, 79, 106, /* 152 - 159 */
931 80, 97, 81, 160, 82, 99, 83, 134, /* 160 - 167 */
932 84, 86, 85, 95, 86, 160, 87, 100, /* 168 - 175 */
933 88, 113, 89, 98, 90, 107, 91, 122, /* 176 - 183 */
934 92, 111, 93, 102, 94, 126, 95, 150, /* 184 - 191 */
935 96, 128, 97, 130, 98, 133, 99, 195, /* 192 - 199 */
936 100, 128, 101, 123, 102, 164, 103, 138, /* 200 - 207 */
937 104, 145, 105, 146, 106, 109, 107, 149, /* 208 - 215 */
938 108, 200, 109, 146, 110, 170, 111, 157, /* 216 - 223 */
939 112, 128, 113, 130, 114, 182, 115, 132, /* 224 - 231 */
940 116, 200, 117, 132, 118, 158, 119, 206, /* 232 - 239 */
941 120, 240, 121, 162, 122, 147, 123, 152, /* 240 - 247 */
942 124, 166, 125, 214, 126, 138, 127, 153, /* 248 - 255 */
946 /* Return the number of multiplications required to calculate
947 powi(x,n) where n is less than POWI_TABLE_SIZE. This is a
948 subroutine of powi_cost. CACHE is an array indicating
949 which exponents have already been calculated. */
952 powi_lookup_cost (unsigned HOST_WIDE_INT n
, bool *cache
)
954 /* If we've already calculated this exponent, then this evaluation
955 doesn't require any additional multiplications. */
960 return powi_lookup_cost (n
- powi_table
[n
], cache
)
961 + powi_lookup_cost (powi_table
[n
], cache
) + 1;
964 /* Return the number of multiplications required to calculate
965 powi(x,n) for an arbitrary x, given the exponent N. This
966 function needs to be kept in sync with powi_as_mults below. */
969 powi_cost (HOST_WIDE_INT n
)
971 bool cache
[POWI_TABLE_SIZE
];
972 unsigned HOST_WIDE_INT digit
;
973 unsigned HOST_WIDE_INT val
;
979 /* Ignore the reciprocal when calculating the cost. */
980 val
= (n
< 0) ? -n
: n
;
982 /* Initialize the exponent cache. */
983 memset (cache
, 0, POWI_TABLE_SIZE
* sizeof (bool));
988 while (val
>= POWI_TABLE_SIZE
)
992 digit
= val
& ((1 << POWI_WINDOW_SIZE
) - 1);
993 result
+= powi_lookup_cost (digit
, cache
)
994 + POWI_WINDOW_SIZE
+ 1;
995 val
>>= POWI_WINDOW_SIZE
;
1004 return result
+ powi_lookup_cost (val
, cache
);
1007 /* Recursive subroutine of powi_as_mults. This function takes the
1008 array, CACHE, of already calculated exponents and an exponent N and
1009 returns a tree that corresponds to CACHE[1]**N, with type TYPE. */
1012 powi_as_mults_1 (gimple_stmt_iterator
*gsi
, location_t loc
, tree type
,
1013 HOST_WIDE_INT n
, tree
*cache
)
1015 tree op0
, op1
, ssa_target
;
1016 unsigned HOST_WIDE_INT digit
;
1019 if (n
< POWI_TABLE_SIZE
&& cache
[n
])
1022 ssa_target
= make_temp_ssa_name (type
, NULL
, "powmult");
1024 if (n
< POWI_TABLE_SIZE
)
1026 cache
[n
] = ssa_target
;
1027 op0
= powi_as_mults_1 (gsi
, loc
, type
, n
- powi_table
[n
], cache
);
1028 op1
= powi_as_mults_1 (gsi
, loc
, type
, powi_table
[n
], cache
);
1032 digit
= n
& ((1 << POWI_WINDOW_SIZE
) - 1);
1033 op0
= powi_as_mults_1 (gsi
, loc
, type
, n
- digit
, cache
);
1034 op1
= powi_as_mults_1 (gsi
, loc
, type
, digit
, cache
);
1038 op0
= powi_as_mults_1 (gsi
, loc
, type
, n
>> 1, cache
);
1042 mult_stmt
= gimple_build_assign (ssa_target
, MULT_EXPR
, op0
, op1
);
1043 gimple_set_location (mult_stmt
, loc
);
1044 gsi_insert_before (gsi
, mult_stmt
, GSI_SAME_STMT
);
1049 /* Convert ARG0**N to a tree of multiplications of ARG0 with itself.
1050 This function needs to be kept in sync with powi_cost above. */
1053 powi_as_mults (gimple_stmt_iterator
*gsi
, location_t loc
,
1054 tree arg0
, HOST_WIDE_INT n
)
1056 tree cache
[POWI_TABLE_SIZE
], result
, type
= TREE_TYPE (arg0
);
1061 return build_real (type
, dconst1
);
1063 memset (cache
, 0, sizeof (cache
));
1066 result
= powi_as_mults_1 (gsi
, loc
, type
, (n
< 0) ? -n
: n
, cache
);
1070 /* If the original exponent was negative, reciprocate the result. */
1071 target
= make_temp_ssa_name (type
, NULL
, "powmult");
1072 div_stmt
= gimple_build_assign (target
, RDIV_EXPR
,
1073 build_real (type
, dconst1
), result
);
1074 gimple_set_location (div_stmt
, loc
);
1075 gsi_insert_before (gsi
, div_stmt
, GSI_SAME_STMT
);
1080 /* ARG0 and N are the two arguments to a powi builtin in GSI with
1081 location info LOC. If the arguments are appropriate, create an
1082 equivalent sequence of statements prior to GSI using an optimal
1083 number of multiplications, and return an expession holding the
1087 gimple_expand_builtin_powi (gimple_stmt_iterator
*gsi
, location_t loc
,
1088 tree arg0
, HOST_WIDE_INT n
)
1090 /* Avoid largest negative number. */
1092 && ((n
>= -1 && n
<= 2)
1093 || (optimize_function_for_speed_p (cfun
)
1094 && powi_cost (n
) <= POWI_MAX_MULTS
)))
1095 return powi_as_mults (gsi
, loc
, arg0
, n
);
1100 /* Build a gimple call statement that calls FN with argument ARG.
1101 Set the lhs of the call statement to a fresh SSA name. Insert the
1102 statement prior to GSI's current position, and return the fresh
1106 build_and_insert_call (gimple_stmt_iterator
*gsi
, location_t loc
,
1112 call_stmt
= gimple_build_call (fn
, 1, arg
);
1113 ssa_target
= make_temp_ssa_name (TREE_TYPE (arg
), NULL
, "powroot");
1114 gimple_set_lhs (call_stmt
, ssa_target
);
1115 gimple_set_location (call_stmt
, loc
);
1116 gsi_insert_before (gsi
, call_stmt
, GSI_SAME_STMT
);
1121 /* Build a gimple binary operation with the given CODE and arguments
1122 ARG0, ARG1, assigning the result to a new SSA name for variable
1123 TARGET. Insert the statement prior to GSI's current position, and
1124 return the fresh SSA name.*/
1127 build_and_insert_binop (gimple_stmt_iterator
*gsi
, location_t loc
,
1128 const char *name
, enum tree_code code
,
1129 tree arg0
, tree arg1
)
1131 tree result
= make_temp_ssa_name (TREE_TYPE (arg0
), NULL
, name
);
1132 gassign
*stmt
= gimple_build_assign (result
, code
, arg0
, arg1
);
1133 gimple_set_location (stmt
, loc
);
1134 gsi_insert_before (gsi
, stmt
, GSI_SAME_STMT
);
1138 /* Build a gimple reference operation with the given CODE and argument
1139 ARG, assigning the result to a new SSA name of TYPE with NAME.
1140 Insert the statement prior to GSI's current position, and return
1141 the fresh SSA name. */
1144 build_and_insert_ref (gimple_stmt_iterator
*gsi
, location_t loc
, tree type
,
1145 const char *name
, enum tree_code code
, tree arg0
)
1147 tree result
= make_temp_ssa_name (type
, NULL
, name
);
1148 gimple
*stmt
= gimple_build_assign (result
, build1 (code
, type
, arg0
));
1149 gimple_set_location (stmt
, loc
);
1150 gsi_insert_before (gsi
, stmt
, GSI_SAME_STMT
);
1154 /* Build a gimple assignment to cast VAL to TYPE. Insert the statement
1155 prior to GSI's current position, and return the fresh SSA name. */
1158 build_and_insert_cast (gimple_stmt_iterator
*gsi
, location_t loc
,
1159 tree type
, tree val
)
1161 tree result
= make_ssa_name (type
);
1162 gassign
*stmt
= gimple_build_assign (result
, NOP_EXPR
, val
);
1163 gimple_set_location (stmt
, loc
);
1164 gsi_insert_before (gsi
, stmt
, GSI_SAME_STMT
);
1168 struct pow_synth_sqrt_info
1171 unsigned int deepest
;
1172 unsigned int num_mults
;
1175 /* Return true iff the real value C can be represented as a
1176 sum of powers of 0.5 up to N. That is:
1177 C == SUM<i from 1..N> (a[i]*(0.5**i)) where a[i] is either 0 or 1.
1178 Record in INFO the various parameters of the synthesis algorithm such
1179 as the factors a[i], the maximum 0.5 power and the number of
1180 multiplications that will be required. */
1183 representable_as_half_series_p (REAL_VALUE_TYPE c
, unsigned n
,
1184 struct pow_synth_sqrt_info
*info
)
1186 REAL_VALUE_TYPE factor
= dconsthalf
;
1187 REAL_VALUE_TYPE remainder
= c
;
1190 info
->num_mults
= 0;
1191 memset (info
->factors
, 0, n
* sizeof (bool));
1193 for (unsigned i
= 0; i
< n
; i
++)
1195 REAL_VALUE_TYPE res
;
1197 /* If something inexact happened bail out now. */
1198 if (real_arithmetic (&res
, MINUS_EXPR
, &remainder
, &factor
))
1201 /* We have hit zero. The number is representable as a sum
1202 of powers of 0.5. */
1203 if (real_equal (&res
, &dconst0
))
1205 info
->factors
[i
] = true;
1206 info
->deepest
= i
+ 1;
1209 else if (!REAL_VALUE_NEGATIVE (res
))
1212 info
->factors
[i
] = true;
1216 info
->factors
[i
] = false;
1218 real_arithmetic (&factor
, MULT_EXPR
, &factor
, &dconsthalf
);
1223 /* Return the tree corresponding to FN being applied
1224 to ARG N times at GSI and LOC.
1225 Look up previous results from CACHE if need be.
1226 cache[0] should contain just plain ARG i.e. FN applied to ARG 0 times. */
1229 get_fn_chain (tree arg
, unsigned int n
, gimple_stmt_iterator
*gsi
,
1230 tree fn
, location_t loc
, tree
*cache
)
1232 tree res
= cache
[n
];
1235 tree prev
= get_fn_chain (arg
, n
- 1, gsi
, fn
, loc
, cache
);
1236 res
= build_and_insert_call (gsi
, loc
, fn
, prev
);
1243 /* Print to STREAM the repeated application of function FNAME to ARG
1244 N times. So, for FNAME = "foo", ARG = "x", N = 2 it would print:
1248 print_nested_fn (FILE* stream
, const char *fname
, const char* arg
,
1252 fprintf (stream
, "%s", arg
);
1255 fprintf (stream
, "%s (", fname
);
1256 print_nested_fn (stream
, fname
, arg
, n
- 1);
1257 fprintf (stream
, ")");
1261 /* Print to STREAM the fractional sequence of sqrt chains
1262 applied to ARG, described by INFO. Used for the dump file. */
1265 dump_fractional_sqrt_sequence (FILE *stream
, const char *arg
,
1266 struct pow_synth_sqrt_info
*info
)
1268 for (unsigned int i
= 0; i
< info
->deepest
; i
++)
1270 bool is_set
= info
->factors
[i
];
1273 print_nested_fn (stream
, "sqrt", arg
, i
+ 1);
1274 if (i
!= info
->deepest
- 1)
1275 fprintf (stream
, " * ");
1280 /* Print to STREAM a representation of raising ARG to an integer
1281 power N. Used for the dump file. */
1284 dump_integer_part (FILE *stream
, const char* arg
, HOST_WIDE_INT n
)
1287 fprintf (stream
, "powi (%s, " HOST_WIDE_INT_PRINT_DEC
")", arg
, n
);
1289 fprintf (stream
, "%s", arg
);
1292 /* Attempt to synthesize a POW[F] (ARG0, ARG1) call using chains of
1293 square roots. Place at GSI and LOC. Limit the maximum depth
1294 of the sqrt chains to MAX_DEPTH. Return the tree holding the
1295 result of the expanded sequence or NULL_TREE if the expansion failed.
1297 This routine assumes that ARG1 is a real number with a fractional part
1298 (the integer exponent case will have been handled earlier in
1299 gimple_expand_builtin_pow).
1302 * For ARG1 composed of a whole part WHOLE_PART and a fractional part
1303 FRAC_PART i.e. WHOLE_PART == floor (ARG1) and
1304 FRAC_PART == ARG1 - WHOLE_PART:
1305 Produce POWI (ARG0, WHOLE_PART) * POW (ARG0, FRAC_PART) where
1306 POW (ARG0, FRAC_PART) is expanded as a product of square root chains
1307 if it can be expressed as such, that is if FRAC_PART satisfies:
1308 FRAC_PART == <SUM from i = 1 until MAX_DEPTH> (a[i] * (0.5**i))
1309 where integer a[i] is either 0 or 1.
1312 POW (x, 3.625) == POWI (x, 3) * POW (x, 0.625)
1313 --> POWI (x, 3) * SQRT (x) * SQRT (SQRT (SQRT (x)))
1315 For ARG1 < 0.0 there are two approaches:
1316 * (A) Expand to 1.0 / POW (ARG0, -ARG1) where POW (ARG0, -ARG1)
1317 is calculated as above.
1320 POW (x, -5.625) == 1.0 / POW (x, 5.625)
1321 --> 1.0 / (POWI (x, 5) * SQRT (x) * SQRT (SQRT (SQRT (x))))
1323 * (B) : WHOLE_PART := - ceil (abs (ARG1))
1324 FRAC_PART := ARG1 - WHOLE_PART
1325 and expand to POW (x, FRAC_PART) / POWI (x, WHOLE_PART).
1327 POW (x, -5.875) == POW (x, 0.125) / POWI (X, 6)
1328 --> SQRT (SQRT (SQRT (x))) / (POWI (x, 6))
1330 For ARG1 < 0.0 we choose between (A) and (B) depending on
1331 how many multiplications we'd have to do.
1332 So, for the example in (B): POW (x, -5.875), if we were to
1333 follow algorithm (A) we would produce:
1334 1.0 / POWI (X, 5) * SQRT (X) * SQRT (SQRT (X)) * SQRT (SQRT (SQRT (X)))
1335 which contains more multiplications than approach (B).
1337 Hopefully, this approach will eliminate potentially expensive POW library
1338 calls when unsafe floating point math is enabled and allow the compiler to
1339 further optimise the multiplies, square roots and divides produced by this
1343 expand_pow_as_sqrts (gimple_stmt_iterator
*gsi
, location_t loc
,
1344 tree arg0
, tree arg1
, HOST_WIDE_INT max_depth
)
1346 tree type
= TREE_TYPE (arg0
);
1347 machine_mode mode
= TYPE_MODE (type
);
1348 tree sqrtfn
= mathfn_built_in (type
, BUILT_IN_SQRT
);
1349 bool one_over
= true;
1354 if (TREE_CODE (arg1
) != REAL_CST
)
1357 REAL_VALUE_TYPE exp_init
= TREE_REAL_CST (arg1
);
1359 gcc_assert (max_depth
> 0);
1360 tree
*cache
= XALLOCAVEC (tree
, max_depth
+ 1);
1362 struct pow_synth_sqrt_info synth_info
;
1363 synth_info
.factors
= XALLOCAVEC (bool, max_depth
+ 1);
1364 synth_info
.deepest
= 0;
1365 synth_info
.num_mults
= 0;
1367 bool neg_exp
= REAL_VALUE_NEGATIVE (exp_init
);
1368 REAL_VALUE_TYPE exp
= real_value_abs (&exp_init
);
1370 /* The whole and fractional parts of exp. */
1371 REAL_VALUE_TYPE whole_part
;
1372 REAL_VALUE_TYPE frac_part
;
1374 real_floor (&whole_part
, mode
, &exp
);
1375 real_arithmetic (&frac_part
, MINUS_EXPR
, &exp
, &whole_part
);
1378 REAL_VALUE_TYPE ceil_whole
= dconst0
;
1379 REAL_VALUE_TYPE ceil_fract
= dconst0
;
1383 real_ceil (&ceil_whole
, mode
, &exp
);
1384 real_arithmetic (&ceil_fract
, MINUS_EXPR
, &ceil_whole
, &exp
);
1387 if (!representable_as_half_series_p (frac_part
, max_depth
, &synth_info
))
1390 /* Check whether it's more profitable to not use 1.0 / ... */
1393 struct pow_synth_sqrt_info alt_synth_info
;
1394 alt_synth_info
.factors
= XALLOCAVEC (bool, max_depth
+ 1);
1395 alt_synth_info
.deepest
= 0;
1396 alt_synth_info
.num_mults
= 0;
1398 if (representable_as_half_series_p (ceil_fract
, max_depth
,
1400 && alt_synth_info
.deepest
<= synth_info
.deepest
1401 && alt_synth_info
.num_mults
< synth_info
.num_mults
)
1403 whole_part
= ceil_whole
;
1404 frac_part
= ceil_fract
;
1405 synth_info
.deepest
= alt_synth_info
.deepest
;
1406 synth_info
.num_mults
= alt_synth_info
.num_mults
;
1407 memcpy (synth_info
.factors
, alt_synth_info
.factors
,
1408 (max_depth
+ 1) * sizeof (bool));
1413 HOST_WIDE_INT n
= real_to_integer (&whole_part
);
1414 REAL_VALUE_TYPE cint
;
1415 real_from_integer (&cint
, VOIDmode
, n
, SIGNED
);
1417 if (!real_identical (&whole_part
, &cint
))
1420 if (powi_cost (n
) + synth_info
.num_mults
> POWI_MAX_MULTS
)
1423 memset (cache
, 0, (max_depth
+ 1) * sizeof (tree
));
1425 tree integer_res
= n
== 0 ? build_real (type
, dconst1
) : arg0
;
1427 /* Calculate the integer part of the exponent. */
1430 integer_res
= gimple_expand_builtin_powi (gsi
, loc
, arg0
, n
);
1439 real_to_decimal (string
, &exp_init
, sizeof (string
), 0, 1);
1440 fprintf (dump_file
, "synthesizing pow (x, %s) as:\n", string
);
1446 fprintf (dump_file
, "1.0 / (");
1447 dump_integer_part (dump_file
, "x", n
);
1449 fprintf (dump_file
, " * ");
1450 dump_fractional_sqrt_sequence (dump_file
, "x", &synth_info
);
1451 fprintf (dump_file
, ")");
1455 dump_fractional_sqrt_sequence (dump_file
, "x", &synth_info
);
1456 fprintf (dump_file
, " / (");
1457 dump_integer_part (dump_file
, "x", n
);
1458 fprintf (dump_file
, ")");
1463 dump_fractional_sqrt_sequence (dump_file
, "x", &synth_info
);
1465 fprintf (dump_file
, " * ");
1466 dump_integer_part (dump_file
, "x", n
);
1469 fprintf (dump_file
, "\ndeepest sqrt chain: %d\n", synth_info
.deepest
);
1473 tree fract_res
= NULL_TREE
;
1476 /* Calculate the fractional part of the exponent. */
1477 for (unsigned i
= 0; i
< synth_info
.deepest
; i
++)
1479 if (synth_info
.factors
[i
])
1481 tree sqrt_chain
= get_fn_chain (arg0
, i
+ 1, gsi
, sqrtfn
, loc
, cache
);
1484 fract_res
= sqrt_chain
;
1487 fract_res
= build_and_insert_binop (gsi
, loc
, "powroot", MULT_EXPR
,
1488 fract_res
, sqrt_chain
);
1492 tree res
= NULL_TREE
;
1499 res
= build_and_insert_binop (gsi
, loc
, "powroot", MULT_EXPR
,
1500 fract_res
, integer_res
);
1504 res
= build_and_insert_binop (gsi
, loc
, "powrootrecip", RDIV_EXPR
,
1505 build_real (type
, dconst1
), res
);
1509 res
= build_and_insert_binop (gsi
, loc
, "powroot", RDIV_EXPR
,
1510 fract_res
, integer_res
);
1514 res
= build_and_insert_binop (gsi
, loc
, "powroot", MULT_EXPR
,
1515 fract_res
, integer_res
);
1519 /* ARG0 and ARG1 are the two arguments to a pow builtin call in GSI
1520 with location info LOC. If possible, create an equivalent and
1521 less expensive sequence of statements prior to GSI, and return an
1522 expession holding the result. */
1525 gimple_expand_builtin_pow (gimple_stmt_iterator
*gsi
, location_t loc
,
1526 tree arg0
, tree arg1
)
1528 REAL_VALUE_TYPE c
, cint
, dconst1_3
, dconst1_4
, dconst1_6
;
1529 REAL_VALUE_TYPE c2
, dconst3
;
1531 tree type
, sqrtfn
, cbrtfn
, sqrt_arg0
, result
, cbrt_x
, powi_cbrt_x
;
1533 bool speed_p
= optimize_bb_for_speed_p (gsi_bb (*gsi
));
1534 bool hw_sqrt_exists
, c_is_int
, c2_is_int
;
1536 dconst1_4
= dconst1
;
1537 SET_REAL_EXP (&dconst1_4
, REAL_EXP (&dconst1_4
) - 2);
1539 /* If the exponent isn't a constant, there's nothing of interest
1541 if (TREE_CODE (arg1
) != REAL_CST
)
1544 /* Don't perform the operation if flag_signaling_nans is on
1545 and the operand is a signaling NaN. */
1546 if (HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1
)))
1547 && ((TREE_CODE (arg0
) == REAL_CST
1548 && REAL_VALUE_ISSIGNALING_NAN (TREE_REAL_CST (arg0
)))
1549 || REAL_VALUE_ISSIGNALING_NAN (TREE_REAL_CST (arg1
))))
1552 /* If the exponent is equivalent to an integer, expand to an optimal
1553 multiplication sequence when profitable. */
1554 c
= TREE_REAL_CST (arg1
);
1555 n
= real_to_integer (&c
);
1556 real_from_integer (&cint
, VOIDmode
, n
, SIGNED
);
1557 c_is_int
= real_identical (&c
, &cint
);
1560 && ((n
>= -1 && n
<= 2)
1561 || (flag_unsafe_math_optimizations
1563 && powi_cost (n
) <= POWI_MAX_MULTS
)))
1564 return gimple_expand_builtin_powi (gsi
, loc
, arg0
, n
);
1566 /* Attempt various optimizations using sqrt and cbrt. */
1567 type
= TREE_TYPE (arg0
);
1568 mode
= TYPE_MODE (type
);
1569 sqrtfn
= mathfn_built_in (type
, BUILT_IN_SQRT
);
1571 /* Optimize pow(x,0.5) = sqrt(x). This replacement is always safe
1572 unless signed zeros must be maintained. pow(-0,0.5) = +0, while
1575 && real_equal (&c
, &dconsthalf
)
1576 && !HONOR_SIGNED_ZEROS (mode
))
1577 return build_and_insert_call (gsi
, loc
, sqrtfn
, arg0
);
1579 hw_sqrt_exists
= optab_handler (sqrt_optab
, mode
) != CODE_FOR_nothing
;
1581 /* Optimize pow(x,1./3.) = cbrt(x). This requires unsafe math
1582 optimizations since 1./3. is not exactly representable. If x
1583 is negative and finite, the correct value of pow(x,1./3.) is
1584 a NaN with the "invalid" exception raised, because the value
1585 of 1./3. actually has an even denominator. The correct value
1586 of cbrt(x) is a negative real value. */
1587 cbrtfn
= mathfn_built_in (type
, BUILT_IN_CBRT
);
1588 dconst1_3
= real_value_truncate (mode
, dconst_third ());
1590 if (flag_unsafe_math_optimizations
1592 && (!HONOR_NANS (mode
) || tree_expr_nonnegative_p (arg0
))
1593 && real_equal (&c
, &dconst1_3
))
1594 return build_and_insert_call (gsi
, loc
, cbrtfn
, arg0
);
1596 /* Optimize pow(x,1./6.) = cbrt(sqrt(x)). Don't do this optimization
1597 if we don't have a hardware sqrt insn. */
1598 dconst1_6
= dconst1_3
;
1599 SET_REAL_EXP (&dconst1_6
, REAL_EXP (&dconst1_6
) - 1);
1601 if (flag_unsafe_math_optimizations
1604 && (!HONOR_NANS (mode
) || tree_expr_nonnegative_p (arg0
))
1607 && real_equal (&c
, &dconst1_6
))
1610 sqrt_arg0
= build_and_insert_call (gsi
, loc
, sqrtfn
, arg0
);
1613 return build_and_insert_call (gsi
, loc
, cbrtfn
, sqrt_arg0
);
1617 /* Attempt to expand the POW as a product of square root chains.
1618 Expand the 0.25 case even when otpimising for size. */
1619 if (flag_unsafe_math_optimizations
1622 && (speed_p
|| real_equal (&c
, &dconst1_4
))
1623 && !HONOR_SIGNED_ZEROS (mode
))
1625 unsigned int max_depth
= speed_p
1626 ? PARAM_VALUE (PARAM_MAX_POW_SQRT_DEPTH
)
1629 tree expand_with_sqrts
1630 = expand_pow_as_sqrts (gsi
, loc
, arg0
, arg1
, max_depth
);
1632 if (expand_with_sqrts
)
1633 return expand_with_sqrts
;
1636 real_arithmetic (&c2
, MULT_EXPR
, &c
, &dconst2
);
1637 n
= real_to_integer (&c2
);
1638 real_from_integer (&cint
, VOIDmode
, n
, SIGNED
);
1639 c2_is_int
= real_identical (&c2
, &cint
);
1641 /* Optimize pow(x,c), where 3c = n for some nonzero integer n, into
1643 powi(x, n/3) * powi(cbrt(x), n%3), n > 0;
1644 1.0 / (powi(x, abs(n)/3) * powi(cbrt(x), abs(n)%3)), n < 0.
1646 Do not calculate the first factor when n/3 = 0. As cbrt(x) is
1647 different from pow(x, 1./3.) due to rounding and behavior with
1648 negative x, we need to constrain this transformation to unsafe
1649 math and positive x or finite math. */
1650 real_from_integer (&dconst3
, VOIDmode
, 3, SIGNED
);
1651 real_arithmetic (&c2
, MULT_EXPR
, &c
, &dconst3
);
1652 real_round (&c2
, mode
, &c2
);
1653 n
= real_to_integer (&c2
);
1654 real_from_integer (&cint
, VOIDmode
, n
, SIGNED
);
1655 real_arithmetic (&c2
, RDIV_EXPR
, &cint
, &dconst3
);
1656 real_convert (&c2
, mode
, &c2
);
1658 if (flag_unsafe_math_optimizations
1660 && (!HONOR_NANS (mode
) || tree_expr_nonnegative_p (arg0
))
1661 && real_identical (&c2
, &c
)
1663 && optimize_function_for_speed_p (cfun
)
1664 && powi_cost (n
/ 3) <= POWI_MAX_MULTS
)
1666 tree powi_x_ndiv3
= NULL_TREE
;
1668 /* Attempt to fold powi(arg0, abs(n/3)) into multiplies. If not
1669 possible or profitable, give up. Skip the degenerate case when
1670 abs(n) < 3, where the result is always 1. */
1671 if (absu_hwi (n
) >= 3)
1673 powi_x_ndiv3
= gimple_expand_builtin_powi (gsi
, loc
, arg0
,
1679 /* Calculate powi(cbrt(x), n%3). Don't use gimple_expand_builtin_powi
1680 as that creates an unnecessary variable. Instead, just produce
1681 either cbrt(x) or cbrt(x) * cbrt(x). */
1682 cbrt_x
= build_and_insert_call (gsi
, loc
, cbrtfn
, arg0
);
1684 if (absu_hwi (n
) % 3 == 1)
1685 powi_cbrt_x
= cbrt_x
;
1687 powi_cbrt_x
= build_and_insert_binop (gsi
, loc
, "powroot", MULT_EXPR
,
1690 /* Multiply the two subexpressions, unless powi(x,abs(n)/3) = 1. */
1691 if (absu_hwi (n
) < 3)
1692 result
= powi_cbrt_x
;
1694 result
= build_and_insert_binop (gsi
, loc
, "powroot", MULT_EXPR
,
1695 powi_x_ndiv3
, powi_cbrt_x
);
1697 /* If n is negative, reciprocate the result. */
1699 result
= build_and_insert_binop (gsi
, loc
, "powroot", RDIV_EXPR
,
1700 build_real (type
, dconst1
), result
);
1705 /* No optimizations succeeded. */
1709 /* ARG is the argument to a cabs builtin call in GSI with location info
1710 LOC. Create a sequence of statements prior to GSI that calculates
1711 sqrt(R*R + I*I), where R and I are the real and imaginary components
1712 of ARG, respectively. Return an expression holding the result. */
1715 gimple_expand_builtin_cabs (gimple_stmt_iterator
*gsi
, location_t loc
, tree arg
)
1717 tree real_part
, imag_part
, addend1
, addend2
, sum
, result
;
1718 tree type
= TREE_TYPE (TREE_TYPE (arg
));
1719 tree sqrtfn
= mathfn_built_in (type
, BUILT_IN_SQRT
);
1720 machine_mode mode
= TYPE_MODE (type
);
1722 if (!flag_unsafe_math_optimizations
1723 || !optimize_bb_for_speed_p (gimple_bb (gsi_stmt (*gsi
)))
1725 || optab_handler (sqrt_optab
, mode
) == CODE_FOR_nothing
)
1728 real_part
= build_and_insert_ref (gsi
, loc
, type
, "cabs",
1729 REALPART_EXPR
, arg
);
1730 addend1
= build_and_insert_binop (gsi
, loc
, "cabs", MULT_EXPR
,
1731 real_part
, real_part
);
1732 imag_part
= build_and_insert_ref (gsi
, loc
, type
, "cabs",
1733 IMAGPART_EXPR
, arg
);
1734 addend2
= build_and_insert_binop (gsi
, loc
, "cabs", MULT_EXPR
,
1735 imag_part
, imag_part
);
1736 sum
= build_and_insert_binop (gsi
, loc
, "cabs", PLUS_EXPR
, addend1
, addend2
);
1737 result
= build_and_insert_call (gsi
, loc
, sqrtfn
, sum
);
1742 /* Go through all calls to sin, cos and cexpi and call execute_cse_sincos_1
1743 on the SSA_NAME argument of each of them. Also expand powi(x,n) into
1744 an optimal number of multiplies, when n is a constant. */
1748 const pass_data pass_data_cse_sincos
=
1750 GIMPLE_PASS
, /* type */
1751 "sincos", /* name */
1752 OPTGROUP_NONE
, /* optinfo_flags */
1753 TV_NONE
, /* tv_id */
1754 PROP_ssa
, /* properties_required */
1755 PROP_gimple_opt_math
, /* properties_provided */
1756 0, /* properties_destroyed */
1757 0, /* todo_flags_start */
1758 TODO_update_ssa
, /* todo_flags_finish */
1761 class pass_cse_sincos
: public gimple_opt_pass
1764 pass_cse_sincos (gcc::context
*ctxt
)
1765 : gimple_opt_pass (pass_data_cse_sincos
, ctxt
)
1768 /* opt_pass methods: */
1769 virtual bool gate (function
*)
1771 /* We no longer require either sincos or cexp, since powi expansion
1772 piggybacks on this pass. */
1776 virtual unsigned int execute (function
*);
1778 }; // class pass_cse_sincos
1781 pass_cse_sincos::execute (function
*fun
)
1784 bool cfg_changed
= false;
1786 calculate_dominance_info (CDI_DOMINATORS
);
1787 memset (&sincos_stats
, 0, sizeof (sincos_stats
));
1789 FOR_EACH_BB_FN (bb
, fun
)
1791 gimple_stmt_iterator gsi
;
1792 bool cleanup_eh
= false;
1794 for (gsi
= gsi_after_labels (bb
); !gsi_end_p (gsi
); gsi_next (&gsi
))
1796 gimple
*stmt
= gsi_stmt (gsi
);
1798 /* Only the last stmt in a bb could throw, no need to call
1799 gimple_purge_dead_eh_edges if we change something in the middle
1800 of a basic block. */
1803 if (is_gimple_call (stmt
)
1804 && gimple_call_lhs (stmt
))
1806 tree arg
, arg0
, arg1
, result
;
1810 switch (gimple_call_combined_fn (stmt
))
1815 /* Make sure we have either sincos or cexp. */
1816 if (!targetm
.libc_has_function (function_c99_math_complex
)
1817 && !targetm
.libc_has_function (function_sincos
))
1820 arg
= gimple_call_arg (stmt
, 0);
1821 if (TREE_CODE (arg
) == SSA_NAME
)
1822 cfg_changed
|= execute_cse_sincos_1 (arg
);
1826 arg0
= gimple_call_arg (stmt
, 0);
1827 arg1
= gimple_call_arg (stmt
, 1);
1829 loc
= gimple_location (stmt
);
1830 result
= gimple_expand_builtin_pow (&gsi
, loc
, arg0
, arg1
);
1834 tree lhs
= gimple_get_lhs (stmt
);
1835 gassign
*new_stmt
= gimple_build_assign (lhs
, result
);
1836 gimple_set_location (new_stmt
, loc
);
1837 unlink_stmt_vdef (stmt
);
1838 gsi_replace (&gsi
, new_stmt
, true);
1840 if (gimple_vdef (stmt
))
1841 release_ssa_name (gimple_vdef (stmt
));
1846 arg0
= gimple_call_arg (stmt
, 0);
1847 arg1
= gimple_call_arg (stmt
, 1);
1848 loc
= gimple_location (stmt
);
1850 if (real_minus_onep (arg0
))
1852 tree t0
, t1
, cond
, one
, minus_one
;
1855 t0
= TREE_TYPE (arg0
);
1856 t1
= TREE_TYPE (arg1
);
1857 one
= build_real (t0
, dconst1
);
1858 minus_one
= build_real (t0
, dconstm1
);
1860 cond
= make_temp_ssa_name (t1
, NULL
, "powi_cond");
1861 stmt
= gimple_build_assign (cond
, BIT_AND_EXPR
,
1862 arg1
, build_int_cst (t1
, 1));
1863 gimple_set_location (stmt
, loc
);
1864 gsi_insert_before (&gsi
, stmt
, GSI_SAME_STMT
);
1866 result
= make_temp_ssa_name (t0
, NULL
, "powi");
1867 stmt
= gimple_build_assign (result
, COND_EXPR
, cond
,
1869 gimple_set_location (stmt
, loc
);
1870 gsi_insert_before (&gsi
, stmt
, GSI_SAME_STMT
);
1874 if (!tree_fits_shwi_p (arg1
))
1877 n
= tree_to_shwi (arg1
);
1878 result
= gimple_expand_builtin_powi (&gsi
, loc
, arg0
, n
);
1883 tree lhs
= gimple_get_lhs (stmt
);
1884 gassign
*new_stmt
= gimple_build_assign (lhs
, result
);
1885 gimple_set_location (new_stmt
, loc
);
1886 unlink_stmt_vdef (stmt
);
1887 gsi_replace (&gsi
, new_stmt
, true);
1889 if (gimple_vdef (stmt
))
1890 release_ssa_name (gimple_vdef (stmt
));
1895 arg0
= gimple_call_arg (stmt
, 0);
1896 loc
= gimple_location (stmt
);
1897 result
= gimple_expand_builtin_cabs (&gsi
, loc
, arg0
);
1901 tree lhs
= gimple_get_lhs (stmt
);
1902 gassign
*new_stmt
= gimple_build_assign (lhs
, result
);
1903 gimple_set_location (new_stmt
, loc
);
1904 unlink_stmt_vdef (stmt
);
1905 gsi_replace (&gsi
, new_stmt
, true);
1907 if (gimple_vdef (stmt
))
1908 release_ssa_name (gimple_vdef (stmt
));
1917 cfg_changed
|= gimple_purge_dead_eh_edges (bb
);
1920 statistics_counter_event (fun
, "sincos statements inserted",
1921 sincos_stats
.inserted
);
1923 return cfg_changed
? TODO_cleanup_cfg
: 0;
1929 make_pass_cse_sincos (gcc::context
*ctxt
)
1931 return new pass_cse_sincos (ctxt
);
1934 /* A symbolic number is used to detect byte permutation and selection
1935 patterns. Therefore the field N contains an artificial number
1936 consisting of octet sized markers:
1938 0 - target byte has the value 0
1939 FF - target byte has an unknown value (eg. due to sign extension)
1940 1..size - marker value is the target byte index minus one.
1942 To detect permutations on memory sources (arrays and structures), a symbolic
1943 number is also associated a base address (the array or structure the load is
1944 made from), an offset from the base address and a range which gives the
1945 difference between the highest and lowest accessed memory location to make
1946 such a symbolic number. The range is thus different from size which reflects
1947 the size of the type of current expression. Note that for non memory source,
1948 range holds the same value as size.
1950 For instance, for an array char a[], (short) a[0] | (short) a[3] would have
1951 a size of 2 but a range of 4 while (short) a[0] | ((short) a[0] << 1) would
1952 still have a size of 2 but this time a range of 1. */
1954 struct symbolic_number
{
1959 HOST_WIDE_INT bytepos
;
1962 unsigned HOST_WIDE_INT range
;
1965 #define BITS_PER_MARKER 8
1966 #define MARKER_MASK ((1 << BITS_PER_MARKER) - 1)
1967 #define MARKER_BYTE_UNKNOWN MARKER_MASK
1968 #define HEAD_MARKER(n, size) \
1969 ((n) & ((uint64_t) MARKER_MASK << (((size) - 1) * BITS_PER_MARKER)))
1971 /* The number which the find_bswap_or_nop_1 result should match in
1972 order to have a nop. The number is masked according to the size of
1973 the symbolic number before using it. */
1974 #define CMPNOP (sizeof (int64_t) < 8 ? 0 : \
1975 (uint64_t)0x08070605 << 32 | 0x04030201)
1977 /* The number which the find_bswap_or_nop_1 result should match in
1978 order to have a byte swap. The number is masked according to the
1979 size of the symbolic number before using it. */
1980 #define CMPXCHG (sizeof (int64_t) < 8 ? 0 : \
1981 (uint64_t)0x01020304 << 32 | 0x05060708)
1983 /* Perform a SHIFT or ROTATE operation by COUNT bits on symbolic
1984 number N. Return false if the requested operation is not permitted
1985 on a symbolic number. */
1988 do_shift_rotate (enum tree_code code
,
1989 struct symbolic_number
*n
,
1992 int i
, size
= TYPE_PRECISION (n
->type
) / BITS_PER_UNIT
;
1993 unsigned head_marker
;
1995 if (count
% BITS_PER_UNIT
!= 0)
1997 count
= (count
/ BITS_PER_UNIT
) * BITS_PER_MARKER
;
1999 /* Zero out the extra bits of N in order to avoid them being shifted
2000 into the significant bits. */
2001 if (size
< 64 / BITS_PER_MARKER
)
2002 n
->n
&= ((uint64_t) 1 << (size
* BITS_PER_MARKER
)) - 1;
2010 head_marker
= HEAD_MARKER (n
->n
, size
);
2012 /* Arithmetic shift of signed type: result is dependent on the value. */
2013 if (!TYPE_UNSIGNED (n
->type
) && head_marker
)
2014 for (i
= 0; i
< count
/ BITS_PER_MARKER
; i
++)
2015 n
->n
|= (uint64_t) MARKER_BYTE_UNKNOWN
2016 << ((size
- 1 - i
) * BITS_PER_MARKER
);
2019 n
->n
= (n
->n
<< count
) | (n
->n
>> ((size
* BITS_PER_MARKER
) - count
));
2022 n
->n
= (n
->n
>> count
) | (n
->n
<< ((size
* BITS_PER_MARKER
) - count
));
2027 /* Zero unused bits for size. */
2028 if (size
< 64 / BITS_PER_MARKER
)
2029 n
->n
&= ((uint64_t) 1 << (size
* BITS_PER_MARKER
)) - 1;
2033 /* Perform sanity checking for the symbolic number N and the gimple
2037 verify_symbolic_number_p (struct symbolic_number
*n
, gimple
*stmt
)
2041 lhs_type
= gimple_expr_type (stmt
);
2043 if (TREE_CODE (lhs_type
) != INTEGER_TYPE
)
2046 if (TYPE_PRECISION (lhs_type
) != TYPE_PRECISION (n
->type
))
2052 /* Initialize the symbolic number N for the bswap pass from the base element
2053 SRC manipulated by the bitwise OR expression. */
2056 init_symbolic_number (struct symbolic_number
*n
, tree src
)
2060 if (! INTEGRAL_TYPE_P (TREE_TYPE (src
)))
2063 n
->base_addr
= n
->offset
= n
->alias_set
= n
->vuse
= NULL_TREE
;
2065 /* Set up the symbolic number N by setting each byte to a value between 1 and
2066 the byte size of rhs1. The highest order byte is set to n->size and the
2067 lowest order byte to 1. */
2068 n
->type
= TREE_TYPE (src
);
2069 size
= TYPE_PRECISION (n
->type
);
2070 if (size
% BITS_PER_UNIT
!= 0)
2072 size
/= BITS_PER_UNIT
;
2073 if (size
> 64 / BITS_PER_MARKER
)
2078 if (size
< 64 / BITS_PER_MARKER
)
2079 n
->n
&= ((uint64_t) 1 << (size
* BITS_PER_MARKER
)) - 1;
2084 /* Check if STMT might be a byte swap or a nop from a memory source and returns
2085 the answer. If so, REF is that memory source and the base of the memory area
2086 accessed and the offset of the access from that base are recorded in N. */
2089 find_bswap_or_nop_load (gimple
*stmt
, tree ref
, struct symbolic_number
*n
)
2091 /* Leaf node is an array or component ref. Memorize its base and
2092 offset from base to compare to other such leaf node. */
2093 HOST_WIDE_INT bitsize
, bitpos
;
2095 int unsignedp
, reversep
, volatilep
;
2096 tree offset
, base_addr
;
2098 /* Not prepared to handle PDP endian. */
2099 if (BYTES_BIG_ENDIAN
!= WORDS_BIG_ENDIAN
)
2102 if (!gimple_assign_load_p (stmt
) || gimple_has_volatile_ops (stmt
))
2105 base_addr
= get_inner_reference (ref
, &bitsize
, &bitpos
, &offset
, &mode
,
2106 &unsignedp
, &reversep
, &volatilep
);
2108 if (TREE_CODE (base_addr
) == MEM_REF
)
2110 offset_int bit_offset
= 0;
2111 tree off
= TREE_OPERAND (base_addr
, 1);
2113 if (!integer_zerop (off
))
2115 offset_int boff
, coff
= mem_ref_offset (base_addr
);
2116 boff
= coff
<< LOG2_BITS_PER_UNIT
;
2120 base_addr
= TREE_OPERAND (base_addr
, 0);
2122 /* Avoid returning a negative bitpos as this may wreak havoc later. */
2123 if (wi::neg_p (bit_offset
))
2125 offset_int mask
= wi::mask
<offset_int
> (LOG2_BITS_PER_UNIT
, false);
2126 offset_int tem
= bit_offset
.and_not (mask
);
2127 /* TEM is the bitpos rounded to BITS_PER_UNIT towards -Inf.
2128 Subtract it to BIT_OFFSET and add it (scaled) to OFFSET. */
2130 tem
>>= LOG2_BITS_PER_UNIT
;
2132 offset
= size_binop (PLUS_EXPR
, offset
,
2133 wide_int_to_tree (sizetype
, tem
));
2135 offset
= wide_int_to_tree (sizetype
, tem
);
2138 bitpos
+= bit_offset
.to_shwi ();
2141 if (bitpos
% BITS_PER_UNIT
)
2143 if (bitsize
% BITS_PER_UNIT
)
2148 if (!init_symbolic_number (n
, ref
))
2150 n
->base_addr
= base_addr
;
2152 n
->bytepos
= bitpos
/ BITS_PER_UNIT
;
2153 n
->alias_set
= reference_alias_ptr_type (ref
);
2154 n
->vuse
= gimple_vuse (stmt
);
2158 /* Compute the symbolic number N representing the result of a bitwise OR on 2
2159 symbolic number N1 and N2 whose source statements are respectively
2160 SOURCE_STMT1 and SOURCE_STMT2. */
2163 perform_symbolic_merge (gimple
*source_stmt1
, struct symbolic_number
*n1
,
2164 gimple
*source_stmt2
, struct symbolic_number
*n2
,
2165 struct symbolic_number
*n
)
2169 gimple
*source_stmt
;
2170 struct symbolic_number
*n_start
;
2172 tree rhs1
= gimple_assign_rhs1 (source_stmt1
);
2173 if (TREE_CODE (rhs1
) == BIT_FIELD_REF
2174 && TREE_CODE (TREE_OPERAND (rhs1
, 0)) == SSA_NAME
)
2175 rhs1
= TREE_OPERAND (rhs1
, 0);
2176 tree rhs2
= gimple_assign_rhs1 (source_stmt2
);
2177 if (TREE_CODE (rhs2
) == BIT_FIELD_REF
2178 && TREE_CODE (TREE_OPERAND (rhs2
, 0)) == SSA_NAME
)
2179 rhs2
= TREE_OPERAND (rhs2
, 0);
2181 /* Sources are different, cancel bswap if they are not memory location with
2182 the same base (array, structure, ...). */
2186 HOST_WIDE_INT start_sub
, end_sub
, end1
, end2
, end
;
2187 struct symbolic_number
*toinc_n_ptr
, *n_end
;
2189 if (!n1
->base_addr
|| !n2
->base_addr
2190 || !operand_equal_p (n1
->base_addr
, n2
->base_addr
, 0))
2193 if (!n1
->offset
!= !n2
->offset
2194 || (n1
->offset
&& !operand_equal_p (n1
->offset
, n2
->offset
, 0)))
2197 if (n1
->bytepos
< n2
->bytepos
)
2200 start_sub
= n2
->bytepos
- n1
->bytepos
;
2201 source_stmt
= source_stmt1
;
2206 start_sub
= n1
->bytepos
- n2
->bytepos
;
2207 source_stmt
= source_stmt2
;
2210 /* Find the highest address at which a load is performed and
2211 compute related info. */
2212 end1
= n1
->bytepos
+ (n1
->range
- 1);
2213 end2
= n2
->bytepos
+ (n2
->range
- 1);
2217 end_sub
= end2
- end1
;
2222 end_sub
= end1
- end2
;
2224 n_end
= (end2
> end1
) ? n2
: n1
;
2226 /* Find symbolic number whose lsb is the most significant. */
2227 if (BYTES_BIG_ENDIAN
)
2228 toinc_n_ptr
= (n_end
== n1
) ? n2
: n1
;
2230 toinc_n_ptr
= (n_start
== n1
) ? n2
: n1
;
2232 n
->range
= end
- n_start
->bytepos
+ 1;
2234 /* Check that the range of memory covered can be represented by
2235 a symbolic number. */
2236 if (n
->range
> 64 / BITS_PER_MARKER
)
2239 /* Reinterpret byte marks in symbolic number holding the value of
2240 bigger weight according to target endianness. */
2241 inc
= BYTES_BIG_ENDIAN
? end_sub
: start_sub
;
2242 size
= TYPE_PRECISION (n1
->type
) / BITS_PER_UNIT
;
2243 for (i
= 0; i
< size
; i
++, inc
<<= BITS_PER_MARKER
)
2246 = (toinc_n_ptr
->n
>> (i
* BITS_PER_MARKER
)) & MARKER_MASK
;
2247 if (marker
&& marker
!= MARKER_BYTE_UNKNOWN
)
2248 toinc_n_ptr
->n
+= inc
;
2253 n
->range
= n1
->range
;
2255 source_stmt
= source_stmt1
;
2259 || alias_ptr_types_compatible_p (n1
->alias_set
, n2
->alias_set
))
2260 n
->alias_set
= n1
->alias_set
;
2262 n
->alias_set
= ptr_type_node
;
2263 n
->vuse
= n_start
->vuse
;
2264 n
->base_addr
= n_start
->base_addr
;
2265 n
->offset
= n_start
->offset
;
2266 n
->bytepos
= n_start
->bytepos
;
2267 n
->type
= n_start
->type
;
2268 size
= TYPE_PRECISION (n
->type
) / BITS_PER_UNIT
;
2270 for (i
= 0, mask
= MARKER_MASK
; i
< size
; i
++, mask
<<= BITS_PER_MARKER
)
2272 uint64_t masked1
, masked2
;
2274 masked1
= n1
->n
& mask
;
2275 masked2
= n2
->n
& mask
;
2276 if (masked1
&& masked2
&& masked1
!= masked2
)
2279 n
->n
= n1
->n
| n2
->n
;
2284 /* find_bswap_or_nop_1 invokes itself recursively with N and tries to perform
2285 the operation given by the rhs of STMT on the result. If the operation
2286 could successfully be executed the function returns a gimple stmt whose
2287 rhs's first tree is the expression of the source operand and NULL
2291 find_bswap_or_nop_1 (gimple
*stmt
, struct symbolic_number
*n
, int limit
)
2293 enum tree_code code
;
2294 tree rhs1
, rhs2
= NULL
;
2295 gimple
*rhs1_stmt
, *rhs2_stmt
, *source_stmt1
;
2296 enum gimple_rhs_class rhs_class
;
2298 if (!limit
|| !is_gimple_assign (stmt
))
2301 rhs1
= gimple_assign_rhs1 (stmt
);
2303 if (find_bswap_or_nop_load (stmt
, rhs1
, n
))
2306 /* Handle BIT_FIELD_REF. */
2307 if (TREE_CODE (rhs1
) == BIT_FIELD_REF
2308 && TREE_CODE (TREE_OPERAND (rhs1
, 0)) == SSA_NAME
)
2310 unsigned HOST_WIDE_INT bitsize
= tree_to_uhwi (TREE_OPERAND (rhs1
, 1));
2311 unsigned HOST_WIDE_INT bitpos
= tree_to_uhwi (TREE_OPERAND (rhs1
, 2));
2312 if (bitpos
% BITS_PER_UNIT
== 0
2313 && bitsize
% BITS_PER_UNIT
== 0
2314 && init_symbolic_number (n
, TREE_OPERAND (rhs1
, 0)))
2316 /* Handle big-endian bit numbering in BIT_FIELD_REF. */
2317 if (BYTES_BIG_ENDIAN
)
2318 bitpos
= TYPE_PRECISION (n
->type
) - bitpos
- bitsize
;
2321 if (!do_shift_rotate (RSHIFT_EXPR
, n
, bitpos
))
2326 uint64_t tmp
= (1 << BITS_PER_UNIT
) - 1;
2327 for (unsigned i
= 0; i
< bitsize
/ BITS_PER_UNIT
;
2328 i
++, tmp
<<= BITS_PER_UNIT
)
2329 mask
|= (uint64_t) MARKER_MASK
<< (i
* BITS_PER_MARKER
);
2333 n
->type
= TREE_TYPE (rhs1
);
2335 n
->range
= TYPE_PRECISION (n
->type
) / BITS_PER_UNIT
;
2337 return verify_symbolic_number_p (n
, stmt
) ? stmt
: NULL
;
2343 if (TREE_CODE (rhs1
) != SSA_NAME
)
2346 code
= gimple_assign_rhs_code (stmt
);
2347 rhs_class
= gimple_assign_rhs_class (stmt
);
2348 rhs1_stmt
= SSA_NAME_DEF_STMT (rhs1
);
2350 if (rhs_class
== GIMPLE_BINARY_RHS
)
2351 rhs2
= gimple_assign_rhs2 (stmt
);
2353 /* Handle unary rhs and binary rhs with integer constants as second
2356 if (rhs_class
== GIMPLE_UNARY_RHS
2357 || (rhs_class
== GIMPLE_BINARY_RHS
2358 && TREE_CODE (rhs2
) == INTEGER_CST
))
2360 if (code
!= BIT_AND_EXPR
2361 && code
!= LSHIFT_EXPR
2362 && code
!= RSHIFT_EXPR
2363 && code
!= LROTATE_EXPR
2364 && code
!= RROTATE_EXPR
2365 && !CONVERT_EXPR_CODE_P (code
))
2368 source_stmt1
= find_bswap_or_nop_1 (rhs1_stmt
, n
, limit
- 1);
2370 /* If find_bswap_or_nop_1 returned NULL, STMT is a leaf node and
2371 we have to initialize the symbolic number. */
2374 if (gimple_assign_load_p (stmt
)
2375 || !init_symbolic_number (n
, rhs1
))
2377 source_stmt1
= stmt
;
2384 int i
, size
= TYPE_PRECISION (n
->type
) / BITS_PER_UNIT
;
2385 uint64_t val
= int_cst_value (rhs2
), mask
= 0;
2386 uint64_t tmp
= (1 << BITS_PER_UNIT
) - 1;
2388 /* Only constants masking full bytes are allowed. */
2389 for (i
= 0; i
< size
; i
++, tmp
<<= BITS_PER_UNIT
)
2390 if ((val
& tmp
) != 0 && (val
& tmp
) != tmp
)
2393 mask
|= (uint64_t) MARKER_MASK
<< (i
* BITS_PER_MARKER
);
2402 if (!do_shift_rotate (code
, n
, (int) TREE_INT_CST_LOW (rhs2
)))
2407 int i
, type_size
, old_type_size
;
2410 type
= gimple_expr_type (stmt
);
2411 type_size
= TYPE_PRECISION (type
);
2412 if (type_size
% BITS_PER_UNIT
!= 0)
2414 type_size
/= BITS_PER_UNIT
;
2415 if (type_size
> 64 / BITS_PER_MARKER
)
2418 /* Sign extension: result is dependent on the value. */
2419 old_type_size
= TYPE_PRECISION (n
->type
) / BITS_PER_UNIT
;
2420 if (!TYPE_UNSIGNED (n
->type
) && type_size
> old_type_size
2421 && HEAD_MARKER (n
->n
, old_type_size
))
2422 for (i
= 0; i
< type_size
- old_type_size
; i
++)
2423 n
->n
|= (uint64_t) MARKER_BYTE_UNKNOWN
2424 << ((type_size
- 1 - i
) * BITS_PER_MARKER
);
2426 if (type_size
< 64 / BITS_PER_MARKER
)
2428 /* If STMT casts to a smaller type mask out the bits not
2429 belonging to the target type. */
2430 n
->n
&= ((uint64_t) 1 << (type_size
* BITS_PER_MARKER
)) - 1;
2434 n
->range
= type_size
;
2440 return verify_symbolic_number_p (n
, stmt
) ? source_stmt1
: NULL
;
2443 /* Handle binary rhs. */
2445 if (rhs_class
== GIMPLE_BINARY_RHS
)
2447 struct symbolic_number n1
, n2
;
2448 gimple
*source_stmt
, *source_stmt2
;
2450 if (code
!= BIT_IOR_EXPR
)
2453 if (TREE_CODE (rhs2
) != SSA_NAME
)
2456 rhs2_stmt
= SSA_NAME_DEF_STMT (rhs2
);
2461 source_stmt1
= find_bswap_or_nop_1 (rhs1_stmt
, &n1
, limit
- 1);
2466 source_stmt2
= find_bswap_or_nop_1 (rhs2_stmt
, &n2
, limit
- 1);
2471 if (TYPE_PRECISION (n1
.type
) != TYPE_PRECISION (n2
.type
))
2474 if (!n1
.vuse
!= !n2
.vuse
2475 || (n1
.vuse
&& !operand_equal_p (n1
.vuse
, n2
.vuse
, 0)))
2479 = perform_symbolic_merge (source_stmt1
, &n1
, source_stmt2
, &n2
, n
);
2484 if (!verify_symbolic_number_p (n
, stmt
))
2496 /* Check if STMT completes a bswap implementation or a read in a given
2497 endianness consisting of ORs, SHIFTs and ANDs and sets *BSWAP
2498 accordingly. It also sets N to represent the kind of operations
2499 performed: size of the resulting expression and whether it works on
2500 a memory source, and if so alias-set and vuse. At last, the
2501 function returns a stmt whose rhs's first tree is the source
2505 find_bswap_or_nop (gimple
*stmt
, struct symbolic_number
*n
, bool *bswap
)
2508 uint64_t tmpn
, mask
;
2509 /* The number which the find_bswap_or_nop_1 result should match in order
2510 to have a full byte swap. The number is shifted to the right
2511 according to the size of the symbolic number before using it. */
2512 uint64_t cmpxchg
= CMPXCHG
;
2513 uint64_t cmpnop
= CMPNOP
;
2515 gimple
*source_stmt
;
2518 /* The last parameter determines the depth search limit. It usually
2519 correlates directly to the number n of bytes to be touched. We
2520 increase that number by log2(n) + 1 here in order to also
2521 cover signed -> unsigned conversions of the src operand as can be seen
2522 in libgcc, and for initial shift/and operation of the src operand. */
2523 limit
= TREE_INT_CST_LOW (TYPE_SIZE_UNIT (gimple_expr_type (stmt
)));
2524 limit
+= 1 + (int) ceil_log2 ((unsigned HOST_WIDE_INT
) limit
);
2525 source_stmt
= find_bswap_or_nop_1 (stmt
, n
, limit
);
2530 /* Find real size of result (highest non-zero byte). */
2532 for (tmpn
= n
->n
, rsize
= 0; tmpn
; tmpn
>>= BITS_PER_MARKER
, rsize
++);
2536 /* Zero out the bits corresponding to untouched bytes in original gimple
2538 if (n
->range
< (int) sizeof (int64_t))
2540 mask
= ((uint64_t) 1 << (n
->range
* BITS_PER_MARKER
)) - 1;
2541 cmpxchg
>>= (64 / BITS_PER_MARKER
- n
->range
) * BITS_PER_MARKER
;
2545 /* Zero out the bits corresponding to unused bytes in the result of the
2546 gimple expression. */
2547 if (rsize
< n
->range
)
2549 if (BYTES_BIG_ENDIAN
)
2551 mask
= ((uint64_t) 1 << (rsize
* BITS_PER_MARKER
)) - 1;
2553 cmpnop
>>= (n
->range
- rsize
) * BITS_PER_MARKER
;
2557 mask
= ((uint64_t) 1 << (rsize
* BITS_PER_MARKER
)) - 1;
2558 cmpxchg
>>= (n
->range
- rsize
) * BITS_PER_MARKER
;
2564 /* A complete byte swap should make the symbolic number to start with
2565 the largest digit in the highest order byte. Unchanged symbolic
2566 number indicates a read with same endianness as target architecture. */
2569 else if (n
->n
== cmpxchg
)
2574 /* Useless bit manipulation performed by code. */
2575 if (!n
->base_addr
&& n
->n
== cmpnop
)
2578 n
->range
*= BITS_PER_UNIT
;
2584 const pass_data pass_data_optimize_bswap
=
2586 GIMPLE_PASS
, /* type */
2588 OPTGROUP_NONE
, /* optinfo_flags */
2589 TV_NONE
, /* tv_id */
2590 PROP_ssa
, /* properties_required */
2591 0, /* properties_provided */
2592 0, /* properties_destroyed */
2593 0, /* todo_flags_start */
2594 0, /* todo_flags_finish */
2597 class pass_optimize_bswap
: public gimple_opt_pass
2600 pass_optimize_bswap (gcc::context
*ctxt
)
2601 : gimple_opt_pass (pass_data_optimize_bswap
, ctxt
)
2604 /* opt_pass methods: */
2605 virtual bool gate (function
*)
2607 return flag_expensive_optimizations
&& optimize
;
2610 virtual unsigned int execute (function
*);
2612 }; // class pass_optimize_bswap
2614 /* Perform the bswap optimization: replace the expression computed in the rhs
2615 of CUR_STMT by an equivalent bswap, load or load + bswap expression.
2616 Which of these alternatives replace the rhs is given by N->base_addr (non
2617 null if a load is needed) and BSWAP. The type, VUSE and set-alias of the
2618 load to perform are also given in N while the builtin bswap invoke is given
2619 in FNDEL. Finally, if a load is involved, SRC_STMT refers to one of the
2620 load statements involved to construct the rhs in CUR_STMT and N->range gives
2621 the size of the rhs expression for maintaining some statistics.
2623 Note that if the replacement involve a load, CUR_STMT is moved just after
2624 SRC_STMT to do the load with the same VUSE which can lead to CUR_STMT
2625 changing of basic block. */
2628 bswap_replace (gimple
*cur_stmt
, gimple
*src_stmt
, tree fndecl
,
2629 tree bswap_type
, tree load_type
, struct symbolic_number
*n
,
2632 gimple_stmt_iterator gsi
;
2636 gsi
= gsi_for_stmt (cur_stmt
);
2637 src
= gimple_assign_rhs1 (src_stmt
);
2638 tgt
= gimple_assign_lhs (cur_stmt
);
2640 /* Need to load the value from memory first. */
2643 gimple_stmt_iterator gsi_ins
= gsi_for_stmt (src_stmt
);
2644 tree addr_expr
, addr_tmp
, val_expr
, val_tmp
;
2645 tree load_offset_ptr
, aligned_load_type
;
2646 gimple
*addr_stmt
, *load_stmt
;
2648 HOST_WIDE_INT load_offset
= 0;
2650 align
= get_object_alignment (src
);
2653 && align
< GET_MODE_ALIGNMENT (TYPE_MODE (load_type
))
2654 && SLOW_UNALIGNED_ACCESS (TYPE_MODE (load_type
), align
))
2657 /* Move cur_stmt just before one of the load of the original
2658 to ensure it has the same VUSE. See PR61517 for what could
2660 if (gimple_bb (cur_stmt
) != gimple_bb (src_stmt
))
2661 reset_flow_sensitive_info (gimple_assign_lhs (cur_stmt
));
2662 gsi_move_before (&gsi
, &gsi_ins
);
2663 gsi
= gsi_for_stmt (cur_stmt
);
2665 /* Compute address to load from and cast according to the size
2667 addr_expr
= build_fold_addr_expr (unshare_expr (src
));
2668 if (is_gimple_mem_ref_addr (addr_expr
))
2669 addr_tmp
= addr_expr
;
2672 addr_tmp
= make_temp_ssa_name (TREE_TYPE (addr_expr
), NULL
,
2674 addr_stmt
= gimple_build_assign (addr_tmp
, addr_expr
);
2675 gsi_insert_before (&gsi
, addr_stmt
, GSI_SAME_STMT
);
2678 /* Perform the load. */
2679 aligned_load_type
= load_type
;
2680 if (align
< TYPE_ALIGN (load_type
))
2681 aligned_load_type
= build_aligned_type (load_type
, align
);
2682 load_offset_ptr
= build_int_cst (n
->alias_set
, load_offset
);
2683 val_expr
= fold_build2 (MEM_REF
, aligned_load_type
, addr_tmp
,
2689 nop_stats
.found_16bit
++;
2690 else if (n
->range
== 32)
2691 nop_stats
.found_32bit
++;
2694 gcc_assert (n
->range
== 64);
2695 nop_stats
.found_64bit
++;
2698 /* Convert the result of load if necessary. */
2699 if (!useless_type_conversion_p (TREE_TYPE (tgt
), load_type
))
2701 val_tmp
= make_temp_ssa_name (aligned_load_type
, NULL
,
2703 load_stmt
= gimple_build_assign (val_tmp
, val_expr
);
2704 gimple_set_vuse (load_stmt
, n
->vuse
);
2705 gsi_insert_before (&gsi
, load_stmt
, GSI_SAME_STMT
);
2706 gimple_assign_set_rhs_with_ops (&gsi
, NOP_EXPR
, val_tmp
);
2710 gimple_assign_set_rhs_with_ops (&gsi
, MEM_REF
, val_expr
);
2711 gimple_set_vuse (cur_stmt
, n
->vuse
);
2713 update_stmt (cur_stmt
);
2718 "%d bit load in target endianness found at: ",
2720 print_gimple_stmt (dump_file
, cur_stmt
, 0, 0);
2726 val_tmp
= make_temp_ssa_name (aligned_load_type
, NULL
, "load_dst");
2727 load_stmt
= gimple_build_assign (val_tmp
, val_expr
);
2728 gimple_set_vuse (load_stmt
, n
->vuse
);
2729 gsi_insert_before (&gsi
, load_stmt
, GSI_SAME_STMT
);
2733 else if (TREE_CODE (src
) == BIT_FIELD_REF
)
2734 src
= TREE_OPERAND (src
, 0);
2737 bswap_stats
.found_16bit
++;
2738 else if (n
->range
== 32)
2739 bswap_stats
.found_32bit
++;
2742 gcc_assert (n
->range
== 64);
2743 bswap_stats
.found_64bit
++;
2748 /* Convert the src expression if necessary. */
2749 if (!useless_type_conversion_p (TREE_TYPE (tmp
), bswap_type
))
2751 gimple
*convert_stmt
;
2753 tmp
= make_temp_ssa_name (bswap_type
, NULL
, "bswapsrc");
2754 convert_stmt
= gimple_build_assign (tmp
, NOP_EXPR
, src
);
2755 gsi_insert_before (&gsi
, convert_stmt
, GSI_SAME_STMT
);
2758 /* Canonical form for 16 bit bswap is a rotate expression. Only 16bit values
2759 are considered as rotation of 2N bit values by N bits is generally not
2760 equivalent to a bswap. Consider for instance 0x01020304 r>> 16 which
2761 gives 0x03040102 while a bswap for that value is 0x04030201. */
2762 if (bswap
&& n
->range
== 16)
2764 tree count
= build_int_cst (NULL
, BITS_PER_UNIT
);
2765 src
= fold_build2 (LROTATE_EXPR
, bswap_type
, tmp
, count
);
2766 bswap_stmt
= gimple_build_assign (NULL
, src
);
2769 bswap_stmt
= gimple_build_call (fndecl
, 1, tmp
);
2773 /* Convert the result if necessary. */
2774 if (!useless_type_conversion_p (TREE_TYPE (tgt
), bswap_type
))
2776 gimple
*convert_stmt
;
2778 tmp
= make_temp_ssa_name (bswap_type
, NULL
, "bswapdst");
2779 convert_stmt
= gimple_build_assign (tgt
, NOP_EXPR
, tmp
);
2780 gsi_insert_after (&gsi
, convert_stmt
, GSI_SAME_STMT
);
2783 gimple_set_lhs (bswap_stmt
, tmp
);
2787 fprintf (dump_file
, "%d bit bswap implementation found at: ",
2789 print_gimple_stmt (dump_file
, cur_stmt
, 0, 0);
2792 gsi_insert_after (&gsi
, bswap_stmt
, GSI_SAME_STMT
);
2793 gsi_remove (&gsi
, true);
2797 /* Find manual byte swap implementations as well as load in a given
2798 endianness. Byte swaps are turned into a bswap builtin invokation
2799 while endian loads are converted to bswap builtin invokation or
2800 simple load according to the target endianness. */
2803 pass_optimize_bswap::execute (function
*fun
)
2806 bool bswap32_p
, bswap64_p
;
2807 bool changed
= false;
2808 tree bswap32_type
= NULL_TREE
, bswap64_type
= NULL_TREE
;
2810 if (BITS_PER_UNIT
!= 8)
2813 bswap32_p
= (builtin_decl_explicit_p (BUILT_IN_BSWAP32
)
2814 && optab_handler (bswap_optab
, SImode
) != CODE_FOR_nothing
);
2815 bswap64_p
= (builtin_decl_explicit_p (BUILT_IN_BSWAP64
)
2816 && (optab_handler (bswap_optab
, DImode
) != CODE_FOR_nothing
2817 || (bswap32_p
&& word_mode
== SImode
)));
2819 /* Determine the argument type of the builtins. The code later on
2820 assumes that the return and argument type are the same. */
2823 tree fndecl
= builtin_decl_explicit (BUILT_IN_BSWAP32
);
2824 bswap32_type
= TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (fndecl
)));
2829 tree fndecl
= builtin_decl_explicit (BUILT_IN_BSWAP64
);
2830 bswap64_type
= TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (fndecl
)));
2833 memset (&nop_stats
, 0, sizeof (nop_stats
));
2834 memset (&bswap_stats
, 0, sizeof (bswap_stats
));
2836 FOR_EACH_BB_FN (bb
, fun
)
2838 gimple_stmt_iterator gsi
;
2840 /* We do a reverse scan for bswap patterns to make sure we get the
2841 widest match. As bswap pattern matching doesn't handle previously
2842 inserted smaller bswap replacements as sub-patterns, the wider
2843 variant wouldn't be detected. */
2844 for (gsi
= gsi_last_bb (bb
); !gsi_end_p (gsi
);)
2846 gimple
*src_stmt
, *cur_stmt
= gsi_stmt (gsi
);
2847 tree fndecl
= NULL_TREE
, bswap_type
= NULL_TREE
, load_type
;
2848 enum tree_code code
;
2849 struct symbolic_number n
;
2852 /* This gsi_prev (&gsi) is not part of the for loop because cur_stmt
2853 might be moved to a different basic block by bswap_replace and gsi
2854 must not points to it if that's the case. Moving the gsi_prev
2855 there make sure that gsi points to the statement previous to
2856 cur_stmt while still making sure that all statements are
2857 considered in this basic block. */
2860 if (!is_gimple_assign (cur_stmt
))
2863 code
= gimple_assign_rhs_code (cur_stmt
);
2868 if (!tree_fits_uhwi_p (gimple_assign_rhs2 (cur_stmt
))
2869 || tree_to_uhwi (gimple_assign_rhs2 (cur_stmt
))
2879 src_stmt
= find_bswap_or_nop (cur_stmt
, &n
, &bswap
);
2887 /* Already in canonical form, nothing to do. */
2888 if (code
== LROTATE_EXPR
|| code
== RROTATE_EXPR
)
2890 load_type
= bswap_type
= uint16_type_node
;
2893 load_type
= uint32_type_node
;
2896 fndecl
= builtin_decl_explicit (BUILT_IN_BSWAP32
);
2897 bswap_type
= bswap32_type
;
2901 load_type
= uint64_type_node
;
2904 fndecl
= builtin_decl_explicit (BUILT_IN_BSWAP64
);
2905 bswap_type
= bswap64_type
;
2912 if (bswap
&& !fndecl
&& n
.range
!= 16)
2915 if (bswap_replace (cur_stmt
, src_stmt
, fndecl
, bswap_type
, load_type
,
2921 statistics_counter_event (fun
, "16-bit nop implementations found",
2922 nop_stats
.found_16bit
);
2923 statistics_counter_event (fun
, "32-bit nop implementations found",
2924 nop_stats
.found_32bit
);
2925 statistics_counter_event (fun
, "64-bit nop implementations found",
2926 nop_stats
.found_64bit
);
2927 statistics_counter_event (fun
, "16-bit bswap implementations found",
2928 bswap_stats
.found_16bit
);
2929 statistics_counter_event (fun
, "32-bit bswap implementations found",
2930 bswap_stats
.found_32bit
);
2931 statistics_counter_event (fun
, "64-bit bswap implementations found",
2932 bswap_stats
.found_64bit
);
2934 return (changed
? TODO_update_ssa
: 0);
2940 make_pass_optimize_bswap (gcc::context
*ctxt
)
2942 return new pass_optimize_bswap (ctxt
);
2945 /* Return true if stmt is a type conversion operation that can be stripped
2946 when used in a widening multiply operation. */
2948 widening_mult_conversion_strippable_p (tree result_type
, gimple
*stmt
)
2950 enum tree_code rhs_code
= gimple_assign_rhs_code (stmt
);
2952 if (TREE_CODE (result_type
) == INTEGER_TYPE
)
2957 if (!CONVERT_EXPR_CODE_P (rhs_code
))
2960 op_type
= TREE_TYPE (gimple_assign_lhs (stmt
));
2962 /* If the type of OP has the same precision as the result, then
2963 we can strip this conversion. The multiply operation will be
2964 selected to create the correct extension as a by-product. */
2965 if (TYPE_PRECISION (result_type
) == TYPE_PRECISION (op_type
))
2968 /* We can also strip a conversion if it preserves the signed-ness of
2969 the operation and doesn't narrow the range. */
2970 inner_op_type
= TREE_TYPE (gimple_assign_rhs1 (stmt
));
2972 /* If the inner-most type is unsigned, then we can strip any
2973 intermediate widening operation. If it's signed, then the
2974 intermediate widening operation must also be signed. */
2975 if ((TYPE_UNSIGNED (inner_op_type
)
2976 || TYPE_UNSIGNED (op_type
) == TYPE_UNSIGNED (inner_op_type
))
2977 && TYPE_PRECISION (op_type
) > TYPE_PRECISION (inner_op_type
))
2983 return rhs_code
== FIXED_CONVERT_EXPR
;
2986 /* Return true if RHS is a suitable operand for a widening multiplication,
2987 assuming a target type of TYPE.
2988 There are two cases:
2990 - RHS makes some value at least twice as wide. Store that value
2991 in *NEW_RHS_OUT if so, and store its type in *TYPE_OUT.
2993 - RHS is an integer constant. Store that value in *NEW_RHS_OUT if so,
2994 but leave *TYPE_OUT untouched. */
2997 is_widening_mult_rhs_p (tree type
, tree rhs
, tree
*type_out
,
3003 if (TREE_CODE (rhs
) == SSA_NAME
)
3005 stmt
= SSA_NAME_DEF_STMT (rhs
);
3006 if (is_gimple_assign (stmt
))
3008 if (! widening_mult_conversion_strippable_p (type
, stmt
))
3012 rhs1
= gimple_assign_rhs1 (stmt
);
3014 if (TREE_CODE (rhs1
) == INTEGER_CST
)
3016 *new_rhs_out
= rhs1
;
3025 type1
= TREE_TYPE (rhs1
);
3027 if (TREE_CODE (type1
) != TREE_CODE (type
)
3028 || TYPE_PRECISION (type1
) * 2 > TYPE_PRECISION (type
))
3031 *new_rhs_out
= rhs1
;
3036 if (TREE_CODE (rhs
) == INTEGER_CST
)
3046 /* Return true if STMT performs a widening multiplication, assuming the
3047 output type is TYPE. If so, store the unwidened types of the operands
3048 in *TYPE1_OUT and *TYPE2_OUT respectively. Also fill *RHS1_OUT and
3049 *RHS2_OUT such that converting those operands to types *TYPE1_OUT
3050 and *TYPE2_OUT would give the operands of the multiplication. */
3053 is_widening_mult_p (gimple
*stmt
,
3054 tree
*type1_out
, tree
*rhs1_out
,
3055 tree
*type2_out
, tree
*rhs2_out
)
3057 tree type
= TREE_TYPE (gimple_assign_lhs (stmt
));
3059 if (TREE_CODE (type
) != INTEGER_TYPE
3060 && TREE_CODE (type
) != FIXED_POINT_TYPE
)
3063 if (!is_widening_mult_rhs_p (type
, gimple_assign_rhs1 (stmt
), type1_out
,
3067 if (!is_widening_mult_rhs_p (type
, gimple_assign_rhs2 (stmt
), type2_out
,
3071 if (*type1_out
== NULL
)
3073 if (*type2_out
== NULL
|| !int_fits_type_p (*rhs1_out
, *type2_out
))
3075 *type1_out
= *type2_out
;
3078 if (*type2_out
== NULL
)
3080 if (!int_fits_type_p (*rhs2_out
, *type1_out
))
3082 *type2_out
= *type1_out
;
3085 /* Ensure that the larger of the two operands comes first. */
3086 if (TYPE_PRECISION (*type1_out
) < TYPE_PRECISION (*type2_out
))
3088 std::swap (*type1_out
, *type2_out
);
3089 std::swap (*rhs1_out
, *rhs2_out
);
3095 /* Process a single gimple statement STMT, which has a MULT_EXPR as
3096 its rhs, and try to convert it into a WIDEN_MULT_EXPR. The return
3097 value is true iff we converted the statement. */
3100 convert_mult_to_widen (gimple
*stmt
, gimple_stmt_iterator
*gsi
)
3102 tree lhs
, rhs1
, rhs2
, type
, type1
, type2
;
3103 enum insn_code handler
;
3104 machine_mode to_mode
, from_mode
, actual_mode
;
3106 int actual_precision
;
3107 location_t loc
= gimple_location (stmt
);
3108 bool from_unsigned1
, from_unsigned2
;
3110 lhs
= gimple_assign_lhs (stmt
);
3111 type
= TREE_TYPE (lhs
);
3112 if (TREE_CODE (type
) != INTEGER_TYPE
)
3115 if (!is_widening_mult_p (stmt
, &type1
, &rhs1
, &type2
, &rhs2
))
3118 to_mode
= TYPE_MODE (type
);
3119 from_mode
= TYPE_MODE (type1
);
3120 from_unsigned1
= TYPE_UNSIGNED (type1
);
3121 from_unsigned2
= TYPE_UNSIGNED (type2
);
3123 if (from_unsigned1
&& from_unsigned2
)
3124 op
= umul_widen_optab
;
3125 else if (!from_unsigned1
&& !from_unsigned2
)
3126 op
= smul_widen_optab
;
3128 op
= usmul_widen_optab
;
3130 handler
= find_widening_optab_handler_and_mode (op
, to_mode
, from_mode
,
3133 if (handler
== CODE_FOR_nothing
)
3135 if (op
!= smul_widen_optab
)
3137 /* We can use a signed multiply with unsigned types as long as
3138 there is a wider mode to use, or it is the smaller of the two
3139 types that is unsigned. Note that type1 >= type2, always. */
3140 if ((TYPE_UNSIGNED (type1
)
3141 && TYPE_PRECISION (type1
) == GET_MODE_PRECISION (from_mode
))
3142 || (TYPE_UNSIGNED (type2
)
3143 && TYPE_PRECISION (type2
) == GET_MODE_PRECISION (from_mode
)))
3145 from_mode
= GET_MODE_WIDER_MODE (from_mode
);
3146 if (GET_MODE_SIZE (to_mode
) <= GET_MODE_SIZE (from_mode
))
3150 op
= smul_widen_optab
;
3151 handler
= find_widening_optab_handler_and_mode (op
, to_mode
,
3155 if (handler
== CODE_FOR_nothing
)
3158 from_unsigned1
= from_unsigned2
= false;
3164 /* Ensure that the inputs to the handler are in the correct precison
3165 for the opcode. This will be the full mode size. */
3166 actual_precision
= GET_MODE_PRECISION (actual_mode
);
3167 if (2 * actual_precision
> TYPE_PRECISION (type
))
3169 if (actual_precision
!= TYPE_PRECISION (type1
)
3170 || from_unsigned1
!= TYPE_UNSIGNED (type1
))
3171 rhs1
= build_and_insert_cast (gsi
, loc
,
3172 build_nonstandard_integer_type
3173 (actual_precision
, from_unsigned1
), rhs1
);
3174 if (actual_precision
!= TYPE_PRECISION (type2
)
3175 || from_unsigned2
!= TYPE_UNSIGNED (type2
))
3176 rhs2
= build_and_insert_cast (gsi
, loc
,
3177 build_nonstandard_integer_type
3178 (actual_precision
, from_unsigned2
), rhs2
);
3180 /* Handle constants. */
3181 if (TREE_CODE (rhs1
) == INTEGER_CST
)
3182 rhs1
= fold_convert (type1
, rhs1
);
3183 if (TREE_CODE (rhs2
) == INTEGER_CST
)
3184 rhs2
= fold_convert (type2
, rhs2
);
3186 gimple_assign_set_rhs1 (stmt
, rhs1
);
3187 gimple_assign_set_rhs2 (stmt
, rhs2
);
3188 gimple_assign_set_rhs_code (stmt
, WIDEN_MULT_EXPR
);
3190 widen_mul_stats
.widen_mults_inserted
++;
3194 /* Process a single gimple statement STMT, which is found at the
3195 iterator GSI and has a either a PLUS_EXPR or a MINUS_EXPR as its
3196 rhs (given by CODE), and try to convert it into a
3197 WIDEN_MULT_PLUS_EXPR or a WIDEN_MULT_MINUS_EXPR. The return value
3198 is true iff we converted the statement. */
3201 convert_plusminus_to_widen (gimple_stmt_iterator
*gsi
, gimple
*stmt
,
3202 enum tree_code code
)
3204 gimple
*rhs1_stmt
= NULL
, *rhs2_stmt
= NULL
;
3205 gimple
*conv1_stmt
= NULL
, *conv2_stmt
= NULL
, *conv_stmt
;
3206 tree type
, type1
, type2
, optype
;
3207 tree lhs
, rhs1
, rhs2
, mult_rhs1
, mult_rhs2
, add_rhs
;
3208 enum tree_code rhs1_code
= ERROR_MARK
, rhs2_code
= ERROR_MARK
;
3210 enum tree_code wmult_code
;
3211 enum insn_code handler
;
3212 machine_mode to_mode
, from_mode
, actual_mode
;
3213 location_t loc
= gimple_location (stmt
);
3214 int actual_precision
;
3215 bool from_unsigned1
, from_unsigned2
;
3217 lhs
= gimple_assign_lhs (stmt
);
3218 type
= TREE_TYPE (lhs
);
3219 if (TREE_CODE (type
) != INTEGER_TYPE
3220 && TREE_CODE (type
) != FIXED_POINT_TYPE
)
3223 if (code
== MINUS_EXPR
)
3224 wmult_code
= WIDEN_MULT_MINUS_EXPR
;
3226 wmult_code
= WIDEN_MULT_PLUS_EXPR
;
3228 rhs1
= gimple_assign_rhs1 (stmt
);
3229 rhs2
= gimple_assign_rhs2 (stmt
);
3231 if (TREE_CODE (rhs1
) == SSA_NAME
)
3233 rhs1_stmt
= SSA_NAME_DEF_STMT (rhs1
);
3234 if (is_gimple_assign (rhs1_stmt
))
3235 rhs1_code
= gimple_assign_rhs_code (rhs1_stmt
);
3238 if (TREE_CODE (rhs2
) == SSA_NAME
)
3240 rhs2_stmt
= SSA_NAME_DEF_STMT (rhs2
);
3241 if (is_gimple_assign (rhs2_stmt
))
3242 rhs2_code
= gimple_assign_rhs_code (rhs2_stmt
);
3245 /* Allow for one conversion statement between the multiply
3246 and addition/subtraction statement. If there are more than
3247 one conversions then we assume they would invalidate this
3248 transformation. If that's not the case then they should have
3249 been folded before now. */
3250 if (CONVERT_EXPR_CODE_P (rhs1_code
))
3252 conv1_stmt
= rhs1_stmt
;
3253 rhs1
= gimple_assign_rhs1 (rhs1_stmt
);
3254 if (TREE_CODE (rhs1
) == SSA_NAME
)
3256 rhs1_stmt
= SSA_NAME_DEF_STMT (rhs1
);
3257 if (is_gimple_assign (rhs1_stmt
))
3258 rhs1_code
= gimple_assign_rhs_code (rhs1_stmt
);
3263 if (CONVERT_EXPR_CODE_P (rhs2_code
))
3265 conv2_stmt
= rhs2_stmt
;
3266 rhs2
= gimple_assign_rhs1 (rhs2_stmt
);
3267 if (TREE_CODE (rhs2
) == SSA_NAME
)
3269 rhs2_stmt
= SSA_NAME_DEF_STMT (rhs2
);
3270 if (is_gimple_assign (rhs2_stmt
))
3271 rhs2_code
= gimple_assign_rhs_code (rhs2_stmt
);
3277 /* If code is WIDEN_MULT_EXPR then it would seem unnecessary to call
3278 is_widening_mult_p, but we still need the rhs returns.
3280 It might also appear that it would be sufficient to use the existing
3281 operands of the widening multiply, but that would limit the choice of
3282 multiply-and-accumulate instructions.
3284 If the widened-multiplication result has more than one uses, it is
3285 probably wiser not to do the conversion. */
3286 if (code
== PLUS_EXPR
3287 && (rhs1_code
== MULT_EXPR
|| rhs1_code
== WIDEN_MULT_EXPR
))
3289 if (!has_single_use (rhs1
)
3290 || !is_widening_mult_p (rhs1_stmt
, &type1
, &mult_rhs1
,
3291 &type2
, &mult_rhs2
))
3294 conv_stmt
= conv1_stmt
;
3296 else if (rhs2_code
== MULT_EXPR
|| rhs2_code
== WIDEN_MULT_EXPR
)
3298 if (!has_single_use (rhs2
)
3299 || !is_widening_mult_p (rhs2_stmt
, &type1
, &mult_rhs1
,
3300 &type2
, &mult_rhs2
))
3303 conv_stmt
= conv2_stmt
;
3308 to_mode
= TYPE_MODE (type
);
3309 from_mode
= TYPE_MODE (type1
);
3310 from_unsigned1
= TYPE_UNSIGNED (type1
);
3311 from_unsigned2
= TYPE_UNSIGNED (type2
);
3314 /* There's no such thing as a mixed sign madd yet, so use a wider mode. */
3315 if (from_unsigned1
!= from_unsigned2
)
3317 if (!INTEGRAL_TYPE_P (type
))
3319 /* We can use a signed multiply with unsigned types as long as
3320 there is a wider mode to use, or it is the smaller of the two
3321 types that is unsigned. Note that type1 >= type2, always. */
3323 && TYPE_PRECISION (type1
) == GET_MODE_PRECISION (from_mode
))
3325 && TYPE_PRECISION (type2
) == GET_MODE_PRECISION (from_mode
)))
3327 from_mode
= GET_MODE_WIDER_MODE (from_mode
);
3328 if (GET_MODE_SIZE (from_mode
) >= GET_MODE_SIZE (to_mode
))
3332 from_unsigned1
= from_unsigned2
= false;
3333 optype
= build_nonstandard_integer_type (GET_MODE_PRECISION (from_mode
),
3337 /* If there was a conversion between the multiply and addition
3338 then we need to make sure it fits a multiply-and-accumulate.
3339 The should be a single mode change which does not change the
3343 /* We use the original, unmodified data types for this. */
3344 tree from_type
= TREE_TYPE (gimple_assign_rhs1 (conv_stmt
));
3345 tree to_type
= TREE_TYPE (gimple_assign_lhs (conv_stmt
));
3346 int data_size
= TYPE_PRECISION (type1
) + TYPE_PRECISION (type2
);
3347 bool is_unsigned
= TYPE_UNSIGNED (type1
) && TYPE_UNSIGNED (type2
);
3349 if (TYPE_PRECISION (from_type
) > TYPE_PRECISION (to_type
))
3351 /* Conversion is a truncate. */
3352 if (TYPE_PRECISION (to_type
) < data_size
)
3355 else if (TYPE_PRECISION (from_type
) < TYPE_PRECISION (to_type
))
3357 /* Conversion is an extend. Check it's the right sort. */
3358 if (TYPE_UNSIGNED (from_type
) != is_unsigned
3359 && !(is_unsigned
&& TYPE_PRECISION (from_type
) > data_size
))
3362 /* else convert is a no-op for our purposes. */
3365 /* Verify that the machine can perform a widening multiply
3366 accumulate in this mode/signedness combination, otherwise
3367 this transformation is likely to pessimize code. */
3368 this_optab
= optab_for_tree_code (wmult_code
, optype
, optab_default
);
3369 handler
= find_widening_optab_handler_and_mode (this_optab
, to_mode
,
3370 from_mode
, 0, &actual_mode
);
3372 if (handler
== CODE_FOR_nothing
)
3375 /* Ensure that the inputs to the handler are in the correct precison
3376 for the opcode. This will be the full mode size. */
3377 actual_precision
= GET_MODE_PRECISION (actual_mode
);
3378 if (actual_precision
!= TYPE_PRECISION (type1
)
3379 || from_unsigned1
!= TYPE_UNSIGNED (type1
))
3380 mult_rhs1
= build_and_insert_cast (gsi
, loc
,
3381 build_nonstandard_integer_type
3382 (actual_precision
, from_unsigned1
),
3384 if (actual_precision
!= TYPE_PRECISION (type2
)
3385 || from_unsigned2
!= TYPE_UNSIGNED (type2
))
3386 mult_rhs2
= build_and_insert_cast (gsi
, loc
,
3387 build_nonstandard_integer_type
3388 (actual_precision
, from_unsigned2
),
3391 if (!useless_type_conversion_p (type
, TREE_TYPE (add_rhs
)))
3392 add_rhs
= build_and_insert_cast (gsi
, loc
, type
, add_rhs
);
3394 /* Handle constants. */
3395 if (TREE_CODE (mult_rhs1
) == INTEGER_CST
)
3396 mult_rhs1
= fold_convert (type1
, mult_rhs1
);
3397 if (TREE_CODE (mult_rhs2
) == INTEGER_CST
)
3398 mult_rhs2
= fold_convert (type2
, mult_rhs2
);
3400 gimple_assign_set_rhs_with_ops (gsi
, wmult_code
, mult_rhs1
, mult_rhs2
,
3402 update_stmt (gsi_stmt (*gsi
));
3403 widen_mul_stats
.maccs_inserted
++;
3407 /* Combine the multiplication at MUL_STMT with operands MULOP1 and MULOP2
3408 with uses in additions and subtractions to form fused multiply-add
3409 operations. Returns true if successful and MUL_STMT should be removed. */
3412 convert_mult_to_fma (gimple
*mul_stmt
, tree op1
, tree op2
)
3414 tree mul_result
= gimple_get_lhs (mul_stmt
);
3415 tree type
= TREE_TYPE (mul_result
);
3416 gimple
*use_stmt
, *neguse_stmt
;
3418 use_operand_p use_p
;
3419 imm_use_iterator imm_iter
;
3421 if (FLOAT_TYPE_P (type
)
3422 && flag_fp_contract_mode
== FP_CONTRACT_OFF
)
3425 /* We don't want to do bitfield reduction ops. */
3426 if (INTEGRAL_TYPE_P (type
)
3427 && (TYPE_PRECISION (type
)
3428 != GET_MODE_PRECISION (TYPE_MODE (type
))))
3431 /* If the target doesn't support it, don't generate it. We assume that
3432 if fma isn't available then fms, fnma or fnms are not either. */
3433 if (optab_handler (fma_optab
, TYPE_MODE (type
)) == CODE_FOR_nothing
)
3436 /* If the multiplication has zero uses, it is kept around probably because
3437 of -fnon-call-exceptions. Don't optimize it away in that case,
3439 if (has_zero_uses (mul_result
))
3442 /* Make sure that the multiplication statement becomes dead after
3443 the transformation, thus that all uses are transformed to FMAs.
3444 This means we assume that an FMA operation has the same cost
3446 FOR_EACH_IMM_USE_FAST (use_p
, imm_iter
, mul_result
)
3448 enum tree_code use_code
;
3449 tree result
= mul_result
;
3450 bool negate_p
= false;
3452 use_stmt
= USE_STMT (use_p
);
3454 if (is_gimple_debug (use_stmt
))
3457 /* For now restrict this operations to single basic blocks. In theory
3458 we would want to support sinking the multiplication in
3464 to form a fma in the then block and sink the multiplication to the
3466 if (gimple_bb (use_stmt
) != gimple_bb (mul_stmt
))
3469 if (!is_gimple_assign (use_stmt
))
3472 use_code
= gimple_assign_rhs_code (use_stmt
);
3474 /* A negate on the multiplication leads to FNMA. */
3475 if (use_code
== NEGATE_EXPR
)
3480 result
= gimple_assign_lhs (use_stmt
);
3482 /* Make sure the negate statement becomes dead with this
3483 single transformation. */
3484 if (!single_imm_use (gimple_assign_lhs (use_stmt
),
3485 &use_p
, &neguse_stmt
))
3488 /* Make sure the multiplication isn't also used on that stmt. */
3489 FOR_EACH_PHI_OR_STMT_USE (usep
, neguse_stmt
, iter
, SSA_OP_USE
)
3490 if (USE_FROM_PTR (usep
) == mul_result
)
3494 use_stmt
= neguse_stmt
;
3495 if (gimple_bb (use_stmt
) != gimple_bb (mul_stmt
))
3497 if (!is_gimple_assign (use_stmt
))
3500 use_code
= gimple_assign_rhs_code (use_stmt
);
3507 if (gimple_assign_rhs2 (use_stmt
) == result
)
3508 negate_p
= !negate_p
;
3513 /* FMA can only be formed from PLUS and MINUS. */
3517 /* If the subtrahend (gimple_assign_rhs2 (use_stmt)) is computed
3518 by a MULT_EXPR that we'll visit later, we might be able to
3519 get a more profitable match with fnma.
3520 OTOH, if we don't, a negate / fma pair has likely lower latency
3521 that a mult / subtract pair. */
3522 if (use_code
== MINUS_EXPR
&& !negate_p
3523 && gimple_assign_rhs1 (use_stmt
) == result
3524 && optab_handler (fms_optab
, TYPE_MODE (type
)) == CODE_FOR_nothing
3525 && optab_handler (fnma_optab
, TYPE_MODE (type
)) != CODE_FOR_nothing
)
3527 tree rhs2
= gimple_assign_rhs2 (use_stmt
);
3529 if (TREE_CODE (rhs2
) == SSA_NAME
)
3531 gimple
*stmt2
= SSA_NAME_DEF_STMT (rhs2
);
3532 if (has_single_use (rhs2
)
3533 && is_gimple_assign (stmt2
)
3534 && gimple_assign_rhs_code (stmt2
) == MULT_EXPR
)
3539 /* We can't handle a * b + a * b. */
3540 if (gimple_assign_rhs1 (use_stmt
) == gimple_assign_rhs2 (use_stmt
))
3543 /* While it is possible to validate whether or not the exact form
3544 that we've recognized is available in the backend, the assumption
3545 is that the transformation is never a loss. For instance, suppose
3546 the target only has the plain FMA pattern available. Consider
3547 a*b-c -> fma(a,b,-c): we've exchanged MUL+SUB for FMA+NEG, which
3548 is still two operations. Consider -(a*b)-c -> fma(-a,b,-c): we
3549 still have 3 operations, but in the FMA form the two NEGs are
3550 independent and could be run in parallel. */
3553 FOR_EACH_IMM_USE_STMT (use_stmt
, imm_iter
, mul_result
)
3555 gimple_stmt_iterator gsi
= gsi_for_stmt (use_stmt
);
3556 enum tree_code use_code
;
3557 tree addop
, mulop1
= op1
, result
= mul_result
;
3558 bool negate_p
= false;
3560 if (is_gimple_debug (use_stmt
))
3563 use_code
= gimple_assign_rhs_code (use_stmt
);
3564 if (use_code
== NEGATE_EXPR
)
3566 result
= gimple_assign_lhs (use_stmt
);
3567 single_imm_use (gimple_assign_lhs (use_stmt
), &use_p
, &neguse_stmt
);
3568 gsi_remove (&gsi
, true);
3569 release_defs (use_stmt
);
3571 use_stmt
= neguse_stmt
;
3572 gsi
= gsi_for_stmt (use_stmt
);
3573 use_code
= gimple_assign_rhs_code (use_stmt
);
3577 if (gimple_assign_rhs1 (use_stmt
) == result
)
3579 addop
= gimple_assign_rhs2 (use_stmt
);
3580 /* a * b - c -> a * b + (-c) */
3581 if (gimple_assign_rhs_code (use_stmt
) == MINUS_EXPR
)
3582 addop
= force_gimple_operand_gsi (&gsi
,
3583 build1 (NEGATE_EXPR
,
3585 true, NULL_TREE
, true,
3590 addop
= gimple_assign_rhs1 (use_stmt
);
3591 /* a - b * c -> (-b) * c + a */
3592 if (gimple_assign_rhs_code (use_stmt
) == MINUS_EXPR
)
3593 negate_p
= !negate_p
;
3597 mulop1
= force_gimple_operand_gsi (&gsi
,
3598 build1 (NEGATE_EXPR
,
3600 true, NULL_TREE
, true,
3603 fma_stmt
= gimple_build_assign (gimple_assign_lhs (use_stmt
),
3604 FMA_EXPR
, mulop1
, op2
, addop
);
3605 gsi_replace (&gsi
, fma_stmt
, true);
3606 widen_mul_stats
.fmas_inserted
++;
3613 /* Helper function of match_uaddsub_overflow. Return 1
3614 if USE_STMT is unsigned overflow check ovf != 0 for
3615 STMT, -1 if USE_STMT is unsigned overflow check ovf == 0
3619 uaddsub_overflow_check_p (gimple
*stmt
, gimple
*use_stmt
)
3621 enum tree_code ccode
= ERROR_MARK
;
3622 tree crhs1
= NULL_TREE
, crhs2
= NULL_TREE
;
3623 if (gimple_code (use_stmt
) == GIMPLE_COND
)
3625 ccode
= gimple_cond_code (use_stmt
);
3626 crhs1
= gimple_cond_lhs (use_stmt
);
3627 crhs2
= gimple_cond_rhs (use_stmt
);
3629 else if (is_gimple_assign (use_stmt
))
3631 if (gimple_assign_rhs_class (use_stmt
) == GIMPLE_BINARY_RHS
)
3633 ccode
= gimple_assign_rhs_code (use_stmt
);
3634 crhs1
= gimple_assign_rhs1 (use_stmt
);
3635 crhs2
= gimple_assign_rhs2 (use_stmt
);
3637 else if (gimple_assign_rhs_code (use_stmt
) == COND_EXPR
)
3639 tree cond
= gimple_assign_rhs1 (use_stmt
);
3640 if (COMPARISON_CLASS_P (cond
))
3642 ccode
= TREE_CODE (cond
);
3643 crhs1
= TREE_OPERAND (cond
, 0);
3644 crhs2
= TREE_OPERAND (cond
, 1);
3655 if (TREE_CODE_CLASS (ccode
) != tcc_comparison
)
3658 enum tree_code code
= gimple_assign_rhs_code (stmt
);
3659 tree lhs
= gimple_assign_lhs (stmt
);
3660 tree rhs1
= gimple_assign_rhs1 (stmt
);
3661 tree rhs2
= gimple_assign_rhs2 (stmt
);
3667 /* r = a - b; r > a or r <= a
3668 r = a + b; a > r or a <= r or b > r or b <= r. */
3669 if ((code
== MINUS_EXPR
&& crhs1
== lhs
&& crhs2
== rhs1
)
3670 || (code
== PLUS_EXPR
&& (crhs1
== rhs1
|| crhs1
== rhs2
)
3672 return ccode
== GT_EXPR
? 1 : -1;
3676 /* r = a - b; a < r or a >= r
3677 r = a + b; r < a or r >= a or r < b or r >= b. */
3678 if ((code
== MINUS_EXPR
&& crhs1
== rhs1
&& crhs2
== lhs
)
3679 || (code
== PLUS_EXPR
&& crhs1
== lhs
3680 && (crhs2
== rhs1
|| crhs2
== rhs2
)))
3681 return ccode
== LT_EXPR
? 1 : -1;
3689 /* Recognize for unsigned x
3692 where there are other uses of x and replace it with
3693 _7 = SUB_OVERFLOW (y, z);
3694 x = REALPART_EXPR <_7>;
3695 _8 = IMAGPART_EXPR <_7>;
3697 and similarly for addition. */
3700 match_uaddsub_overflow (gimple_stmt_iterator
*gsi
, gimple
*stmt
,
3701 enum tree_code code
)
3703 tree lhs
= gimple_assign_lhs (stmt
);
3704 tree type
= TREE_TYPE (lhs
);
3705 use_operand_p use_p
;
3706 imm_use_iterator iter
;
3707 bool use_seen
= false;
3708 bool ovf_use_seen
= false;
3711 gcc_checking_assert (code
== PLUS_EXPR
|| code
== MINUS_EXPR
);
3712 if (!INTEGRAL_TYPE_P (type
)
3713 || !TYPE_UNSIGNED (type
)
3714 || has_zero_uses (lhs
)
3715 || has_single_use (lhs
)
3716 || optab_handler (code
== PLUS_EXPR
? uaddv4_optab
: usubv4_optab
,
3717 TYPE_MODE (type
)) == CODE_FOR_nothing
)
3720 FOR_EACH_IMM_USE_FAST (use_p
, iter
, lhs
)
3722 use_stmt
= USE_STMT (use_p
);
3723 if (is_gimple_debug (use_stmt
))
3726 if (uaddsub_overflow_check_p (stmt
, use_stmt
))
3727 ovf_use_seen
= true;
3730 if (ovf_use_seen
&& use_seen
)
3734 if (!ovf_use_seen
|| !use_seen
)
3737 tree ctype
= build_complex_type (type
);
3738 tree rhs1
= gimple_assign_rhs1 (stmt
);
3739 tree rhs2
= gimple_assign_rhs2 (stmt
);
3740 gcall
*g
= gimple_build_call_internal (code
== PLUS_EXPR
3741 ? IFN_ADD_OVERFLOW
: IFN_SUB_OVERFLOW
,
3743 tree ctmp
= make_ssa_name (ctype
);
3744 gimple_call_set_lhs (g
, ctmp
);
3745 gsi_insert_before (gsi
, g
, GSI_SAME_STMT
);
3746 gassign
*g2
= gimple_build_assign (lhs
, REALPART_EXPR
,
3747 build1 (REALPART_EXPR
, type
, ctmp
));
3748 gsi_replace (gsi
, g2
, true);
3749 tree ovf
= make_ssa_name (type
);
3750 g2
= gimple_build_assign (ovf
, IMAGPART_EXPR
,
3751 build1 (IMAGPART_EXPR
, type
, ctmp
));
3752 gsi_insert_after (gsi
, g2
, GSI_NEW_STMT
);
3754 FOR_EACH_IMM_USE_STMT (use_stmt
, iter
, lhs
)
3756 if (is_gimple_debug (use_stmt
))
3759 int ovf_use
= uaddsub_overflow_check_p (stmt
, use_stmt
);
3762 if (gimple_code (use_stmt
) == GIMPLE_COND
)
3764 gcond
*cond_stmt
= as_a
<gcond
*> (use_stmt
);
3765 gimple_cond_set_lhs (cond_stmt
, ovf
);
3766 gimple_cond_set_rhs (cond_stmt
, build_int_cst (type
, 0));
3767 gimple_cond_set_code (cond_stmt
, ovf_use
== 1 ? NE_EXPR
: EQ_EXPR
);
3771 gcc_checking_assert (is_gimple_assign (use_stmt
));
3772 if (gimple_assign_rhs_class (use_stmt
) == GIMPLE_BINARY_RHS
)
3774 gimple_assign_set_rhs1 (use_stmt
, ovf
);
3775 gimple_assign_set_rhs2 (use_stmt
, build_int_cst (type
, 0));
3776 gimple_assign_set_rhs_code (use_stmt
,
3777 ovf_use
== 1 ? NE_EXPR
: EQ_EXPR
);
3781 gcc_checking_assert (gimple_assign_rhs_code (use_stmt
)
3783 tree cond
= build2 (ovf_use
== 1 ? NE_EXPR
: EQ_EXPR
,
3784 boolean_type_node
, ovf
,
3785 build_int_cst (type
, 0));
3786 gimple_assign_set_rhs1 (use_stmt
, cond
);
3789 update_stmt (use_stmt
);
3794 /* Return true if target has support for divmod. */
3797 target_supports_divmod_p (optab divmod_optab
, optab div_optab
, machine_mode mode
)
3799 /* If target supports hardware divmod insn, use it for divmod. */
3800 if (optab_handler (divmod_optab
, mode
) != CODE_FOR_nothing
)
3803 /* Check if libfunc for divmod is available. */
3804 rtx libfunc
= optab_libfunc (divmod_optab
, mode
);
3805 if (libfunc
!= NULL_RTX
)
3807 /* If optab_handler exists for div_optab, perhaps in a wider mode,
3808 we don't want to use the libfunc even if it exists for given mode. */
3809 for (machine_mode div_mode
= mode
;
3810 div_mode
!= VOIDmode
;
3811 div_mode
= GET_MODE_WIDER_MODE (div_mode
))
3812 if (optab_handler (div_optab
, div_mode
) != CODE_FOR_nothing
)
3815 return targetm
.expand_divmod_libfunc
!= NULL
;
3821 /* Check if stmt is candidate for divmod transform. */
3824 divmod_candidate_p (gassign
*stmt
)
3826 tree type
= TREE_TYPE (gimple_assign_lhs (stmt
));
3827 enum machine_mode mode
= TYPE_MODE (type
);
3828 optab divmod_optab
, div_optab
;
3830 if (TYPE_UNSIGNED (type
))
3832 divmod_optab
= udivmod_optab
;
3833 div_optab
= udiv_optab
;
3837 divmod_optab
= sdivmod_optab
;
3838 div_optab
= sdiv_optab
;
3841 tree op1
= gimple_assign_rhs1 (stmt
);
3842 tree op2
= gimple_assign_rhs2 (stmt
);
3844 /* Disable the transform if either is a constant, since division-by-constant
3845 may have specialized expansion. */
3846 if (CONSTANT_CLASS_P (op1
) || CONSTANT_CLASS_P (op2
))
3849 /* Exclude the case where TYPE_OVERFLOW_TRAPS (type) as that should
3850 expand using the [su]divv optabs. */
3851 if (TYPE_OVERFLOW_TRAPS (type
))
3854 if (!target_supports_divmod_p (divmod_optab
, div_optab
, mode
))
3860 /* This function looks for:
3861 t1 = a TRUNC_DIV_EXPR b;
3862 t2 = a TRUNC_MOD_EXPR b;
3863 and transforms it to the following sequence:
3864 complex_tmp = DIVMOD (a, b);
3865 t1 = REALPART_EXPR(a);
3866 t2 = IMAGPART_EXPR(b);
3867 For conditions enabling the transform see divmod_candidate_p().
3869 The pass has three parts:
3870 1) Find top_stmt which is trunc_div or trunc_mod stmt and dominates all
3871 other trunc_div_expr and trunc_mod_expr stmts.
3872 2) Add top_stmt and all trunc_div and trunc_mod stmts dominated by top_stmt
3874 3) Insert DIVMOD call just before top_stmt and update entries in
3875 stmts vector to use return value of DIMOVD (REALEXPR_PART for div,
3876 IMAGPART_EXPR for mod). */
3879 convert_to_divmod (gassign
*stmt
)
3881 if (stmt_can_throw_internal (stmt
)
3882 || !divmod_candidate_p (stmt
))
3885 tree op1
= gimple_assign_rhs1 (stmt
);
3886 tree op2
= gimple_assign_rhs2 (stmt
);
3888 imm_use_iterator use_iter
;
3890 auto_vec
<gimple
*> stmts
;
3892 gimple
*top_stmt
= stmt
;
3893 basic_block top_bb
= gimple_bb (stmt
);
3895 /* Part 1: Try to set top_stmt to "topmost" stmt that dominates
3896 at-least stmt and possibly other trunc_div/trunc_mod stmts
3897 having same operands as stmt. */
3899 FOR_EACH_IMM_USE_STMT (use_stmt
, use_iter
, op1
)
3901 if (is_gimple_assign (use_stmt
)
3902 && (gimple_assign_rhs_code (use_stmt
) == TRUNC_DIV_EXPR
3903 || gimple_assign_rhs_code (use_stmt
) == TRUNC_MOD_EXPR
)
3904 && operand_equal_p (op1
, gimple_assign_rhs1 (use_stmt
), 0)
3905 && operand_equal_p (op2
, gimple_assign_rhs2 (use_stmt
), 0))
3907 if (stmt_can_throw_internal (use_stmt
))
3910 basic_block bb
= gimple_bb (use_stmt
);
3914 if (gimple_uid (use_stmt
) < gimple_uid (top_stmt
))
3915 top_stmt
= use_stmt
;
3917 else if (dominated_by_p (CDI_DOMINATORS
, top_bb
, bb
))
3920 top_stmt
= use_stmt
;
3925 tree top_op1
= gimple_assign_rhs1 (top_stmt
);
3926 tree top_op2
= gimple_assign_rhs2 (top_stmt
);
3928 stmts
.safe_push (top_stmt
);
3929 bool div_seen
= (gimple_assign_rhs_code (top_stmt
) == TRUNC_DIV_EXPR
);
3931 /* Part 2: Add all trunc_div/trunc_mod statements domianted by top_bb
3932 to stmts vector. The 2nd loop will always add stmt to stmts vector, since
3933 gimple_bb (top_stmt) dominates gimple_bb (stmt), so the
3934 2nd loop ends up adding at-least single trunc_mod_expr stmt. */
3936 FOR_EACH_IMM_USE_STMT (use_stmt
, use_iter
, top_op1
)
3938 if (is_gimple_assign (use_stmt
)
3939 && (gimple_assign_rhs_code (use_stmt
) == TRUNC_DIV_EXPR
3940 || gimple_assign_rhs_code (use_stmt
) == TRUNC_MOD_EXPR
)
3941 && operand_equal_p (top_op1
, gimple_assign_rhs1 (use_stmt
), 0)
3942 && operand_equal_p (top_op2
, gimple_assign_rhs2 (use_stmt
), 0))
3944 if (use_stmt
== top_stmt
3945 || stmt_can_throw_internal (use_stmt
)
3946 || !dominated_by_p (CDI_DOMINATORS
, gimple_bb (use_stmt
), top_bb
))
3949 stmts
.safe_push (use_stmt
);
3950 if (gimple_assign_rhs_code (use_stmt
) == TRUNC_DIV_EXPR
)
3958 /* Part 3: Create libcall to internal fn DIVMOD:
3959 divmod_tmp = DIVMOD (op1, op2). */
3961 gcall
*call_stmt
= gimple_build_call_internal (IFN_DIVMOD
, 2, op1
, op2
);
3962 tree res
= make_temp_ssa_name (build_complex_type (TREE_TYPE (op1
)),
3963 call_stmt
, "divmod_tmp");
3964 gimple_call_set_lhs (call_stmt
, res
);
3966 /* Insert the call before top_stmt. */
3967 gimple_stmt_iterator top_stmt_gsi
= gsi_for_stmt (top_stmt
);
3968 gsi_insert_before (&top_stmt_gsi
, call_stmt
, GSI_SAME_STMT
);
3970 widen_mul_stats
.divmod_calls_inserted
++;
3972 /* Update all statements in stmts vector:
3973 lhs = op1 TRUNC_DIV_EXPR op2 -> lhs = REALPART_EXPR<divmod_tmp>
3974 lhs = op1 TRUNC_MOD_EXPR op2 -> lhs = IMAGPART_EXPR<divmod_tmp>. */
3976 for (unsigned i
= 0; stmts
.iterate (i
, &use_stmt
); ++i
)
3980 switch (gimple_assign_rhs_code (use_stmt
))
3982 case TRUNC_DIV_EXPR
:
3983 new_rhs
= fold_build1 (REALPART_EXPR
, TREE_TYPE (op1
), res
);
3986 case TRUNC_MOD_EXPR
:
3987 new_rhs
= fold_build1 (IMAGPART_EXPR
, TREE_TYPE (op1
), res
);
3994 gimple_stmt_iterator gsi
= gsi_for_stmt (use_stmt
);
3995 gimple_assign_set_rhs_from_tree (&gsi
, new_rhs
);
3996 update_stmt (use_stmt
);
4002 /* Find integer multiplications where the operands are extended from
4003 smaller types, and replace the MULT_EXPR with a WIDEN_MULT_EXPR
4004 where appropriate. */
4008 const pass_data pass_data_optimize_widening_mul
=
4010 GIMPLE_PASS
, /* type */
4011 "widening_mul", /* name */
4012 OPTGROUP_NONE
, /* optinfo_flags */
4013 TV_NONE
, /* tv_id */
4014 PROP_ssa
, /* properties_required */
4015 0, /* properties_provided */
4016 0, /* properties_destroyed */
4017 0, /* todo_flags_start */
4018 TODO_update_ssa
, /* todo_flags_finish */
4021 class pass_optimize_widening_mul
: public gimple_opt_pass
4024 pass_optimize_widening_mul (gcc::context
*ctxt
)
4025 : gimple_opt_pass (pass_data_optimize_widening_mul
, ctxt
)
4028 /* opt_pass methods: */
4029 virtual bool gate (function
*)
4031 return flag_expensive_optimizations
&& optimize
;
4034 virtual unsigned int execute (function
*);
4036 }; // class pass_optimize_widening_mul
4039 pass_optimize_widening_mul::execute (function
*fun
)
4042 bool cfg_changed
= false;
4044 memset (&widen_mul_stats
, 0, sizeof (widen_mul_stats
));
4045 calculate_dominance_info (CDI_DOMINATORS
);
4046 renumber_gimple_stmt_uids ();
4048 FOR_EACH_BB_FN (bb
, fun
)
4050 gimple_stmt_iterator gsi
;
4052 for (gsi
= gsi_after_labels (bb
); !gsi_end_p (gsi
);)
4054 gimple
*stmt
= gsi_stmt (gsi
);
4055 enum tree_code code
;
4057 if (is_gimple_assign (stmt
))
4059 code
= gimple_assign_rhs_code (stmt
);
4063 if (!convert_mult_to_widen (stmt
, &gsi
)
4064 && convert_mult_to_fma (stmt
,
4065 gimple_assign_rhs1 (stmt
),
4066 gimple_assign_rhs2 (stmt
)))
4068 gsi_remove (&gsi
, true);
4069 release_defs (stmt
);
4076 if (!convert_plusminus_to_widen (&gsi
, stmt
, code
))
4077 match_uaddsub_overflow (&gsi
, stmt
, code
);
4080 case TRUNC_MOD_EXPR
:
4081 convert_to_divmod (as_a
<gassign
*> (stmt
));
4087 else if (is_gimple_call (stmt
)
4088 && gimple_call_lhs (stmt
))
4090 tree fndecl
= gimple_call_fndecl (stmt
);
4092 && gimple_call_builtin_p (stmt
, BUILT_IN_NORMAL
))
4094 switch (DECL_FUNCTION_CODE (fndecl
))
4099 if (TREE_CODE (gimple_call_arg (stmt
, 1)) == REAL_CST
4101 (&TREE_REAL_CST (gimple_call_arg (stmt
, 1)),
4103 && convert_mult_to_fma (stmt
,
4104 gimple_call_arg (stmt
, 0),
4105 gimple_call_arg (stmt
, 0)))
4107 unlink_stmt_vdef (stmt
);
4108 if (gsi_remove (&gsi
, true)
4109 && gimple_purge_dead_eh_edges (bb
))
4111 release_defs (stmt
);
4124 statistics_counter_event (fun
, "widening multiplications inserted",
4125 widen_mul_stats
.widen_mults_inserted
);
4126 statistics_counter_event (fun
, "widening maccs inserted",
4127 widen_mul_stats
.maccs_inserted
);
4128 statistics_counter_event (fun
, "fused multiply-adds inserted",
4129 widen_mul_stats
.fmas_inserted
);
4130 statistics_counter_event (fun
, "divmod calls inserted",
4131 widen_mul_stats
.divmod_calls_inserted
);
4133 return cfg_changed
? TODO_cleanup_cfg
: 0;
4139 make_pass_optimize_widening_mul (gcc::context
*ctxt
)
4141 return new pass_optimize_widening_mul (ctxt
);