1 /* Global, SSA-based optimizations using mathematical identities.
2 Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011
3 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by the
9 Free Software Foundation; either version 3, or (at your option) any
12 GCC is distributed in the hope that it will be useful, but WITHOUT
13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 /* Currently, the only mini-pass in this file tries to CSE reciprocal
22 operations. These are common in sequences such as this one:
24 modulus = sqrt(x*x + y*y + z*z);
29 that can be optimized to
31 modulus = sqrt(x*x + y*y + z*z);
32 rmodulus = 1.0 / modulus;
37 We do this for loop invariant divisors, and with this pass whenever
38 we notice that a division has the same divisor multiple times.
40 Of course, like in PRE, we don't insert a division if a dominator
41 already has one. However, this cannot be done as an extension of
42 PRE for several reasons.
44 First of all, with some experiments it was found out that the
45 transformation is not always useful if there are only two divisions
46 hy the same divisor. This is probably because modern processors
47 can pipeline the divisions; on older, in-order processors it should
48 still be effective to optimize two divisions by the same number.
49 We make this a param, and it shall be called N in the remainder of
52 Second, if trapping math is active, we have less freedom on where
53 to insert divisions: we can only do so in basic blocks that already
54 contain one. (If divisions don't trap, instead, we can insert
55 divisions elsewhere, which will be in blocks that are common dominators
56 of those that have the division).
58 We really don't want to compute the reciprocal unless a division will
59 be found. To do this, we won't insert the division in a basic block
60 that has less than N divisions *post-dominating* it.
62 The algorithm constructs a subset of the dominator tree, holding the
63 blocks containing the divisions and the common dominators to them,
64 and walk it twice. The first walk is in post-order, and it annotates
65 each block with the number of divisions that post-dominate it: this
66 gives information on where divisions can be inserted profitably.
67 The second walk is in pre-order, and it inserts divisions as explained
68 above, and replaces divisions by multiplications.
70 In the best case, the cost of the pass is O(n_statements). In the
71 worst-case, the cost is due to creating the dominator tree subset,
72 with a cost of O(n_basic_blocks ^ 2); however this can only happen
73 for n_statements / n_basic_blocks statements. So, the amortized cost
74 of creating the dominator tree subset is O(n_basic_blocks) and the
75 worst-case cost of the pass is O(n_statements * n_basic_blocks).
77 More practically, the cost will be small because there are few
78 divisions, and they tend to be in the same basic block, so insert_bb
79 is called very few times.
81 If we did this using domwalk.c, an efficient implementation would have
82 to work on all the variables in a single pass, because we could not
83 work on just a subset of the dominator tree, as we do now, and the
84 cost would also be something like O(n_statements * n_basic_blocks).
85 The data structures would be more complex in order to work on all the
86 variables in a single pass. */
90 #include "coretypes.h"
94 #include "tree-flow.h"
96 #include "tree-pass.h"
97 #include "alloc-pool.h"
98 #include "basic-block.h"
100 #include "gimple-pretty-print.h"
102 /* FIXME: RTL headers have to be included here for optabs. */
103 #include "rtl.h" /* Because optabs.h wants enum rtx_code. */
104 #include "expr.h" /* Because optabs.h wants sepops. */
107 /* This structure represents one basic block that either computes a
108 division, or is a common dominator for basic block that compute a
111 /* The basic block represented by this structure. */
114 /* If non-NULL, the SSA_NAME holding the definition for a reciprocal
118 /* If non-NULL, the GIMPLE_ASSIGN for a reciprocal computation that
119 was inserted in BB. */
120 gimple recip_def_stmt;
122 /* Pointer to a list of "struct occurrence"s for blocks dominated
124 struct occurrence *children;
126 /* Pointer to the next "struct occurrence"s in the list of blocks
127 sharing a common dominator. */
128 struct occurrence *next;
130 /* The number of divisions that are in BB before compute_merit. The
131 number of divisions that are in BB or post-dominate it after
135 /* True if the basic block has a division, false if it is a common
136 dominator for basic blocks that do. If it is false and trapping
137 math is active, BB is not a candidate for inserting a reciprocal. */
138 bool bb_has_division;
143 /* Number of 1.0/X ops inserted. */
146 /* Number of 1.0/FUNC ops inserted. */
152 /* Number of cexpi calls inserted. */
158 /* Number of hand-written 32-bit bswaps found. */
161 /* Number of hand-written 64-bit bswaps found. */
167 /* Number of widening multiplication ops inserted. */
168 int widen_mults_inserted;
170 /* Number of integer multiply-and-accumulate ops inserted. */
173 /* Number of fp fused multiply-add ops inserted. */
177 /* The instance of "struct occurrence" representing the highest
178 interesting block in the dominator tree. */
179 static struct occurrence *occ_head;
181 /* Allocation pool for getting instances of "struct occurrence". */
182 static alloc_pool occ_pool;
186 /* Allocate and return a new struct occurrence for basic block BB, and
187 whose children list is headed by CHILDREN. */
188 static struct occurrence *
189 occ_new (basic_block bb, struct occurrence *children)
191 struct occurrence *occ;
193 bb->aux = occ = (struct occurrence *) pool_alloc (occ_pool);
194 memset (occ, 0, sizeof (struct occurrence));
197 occ->children = children;
202 /* Insert NEW_OCC into our subset of the dominator tree. P_HEAD points to a
203 list of "struct occurrence"s, one per basic block, having IDOM as
204 their common dominator.
206 We try to insert NEW_OCC as deep as possible in the tree, and we also
207 insert any other block that is a common dominator for BB and one
208 block already in the tree. */
211 insert_bb (struct occurrence *new_occ, basic_block idom,
212 struct occurrence **p_head)
214 struct occurrence *occ, **p_occ;
216 for (p_occ = p_head; (occ = *p_occ) != NULL; )
218 basic_block bb = new_occ->bb, occ_bb = occ->bb;
219 basic_block dom = nearest_common_dominator (CDI_DOMINATORS, occ_bb, bb);
222 /* BB dominates OCC_BB. OCC becomes NEW_OCC's child: remove OCC
225 occ->next = new_occ->children;
226 new_occ->children = occ;
228 /* Try the next block (it may as well be dominated by BB). */
231 else if (dom == occ_bb)
233 /* OCC_BB dominates BB. Tail recurse to look deeper. */
234 insert_bb (new_occ, dom, &occ->children);
238 else if (dom != idom)
240 gcc_assert (!dom->aux);
242 /* There is a dominator between IDOM and BB, add it and make
243 two children out of NEW_OCC and OCC. First, remove OCC from
249 /* None of the previous blocks has DOM as a dominator: if we tail
250 recursed, we would reexamine them uselessly. Just switch BB with
251 DOM, and go on looking for blocks dominated by DOM. */
252 new_occ = occ_new (dom, new_occ);
257 /* Nothing special, go on with the next element. */
262 /* No place was found as a child of IDOM. Make BB a sibling of IDOM. */
263 new_occ->next = *p_head;
267 /* Register that we found a division in BB. */
270 register_division_in (basic_block bb)
272 struct occurrence *occ;
274 occ = (struct occurrence *) bb->aux;
277 occ = occ_new (bb, NULL);
278 insert_bb (occ, ENTRY_BLOCK_PTR, &occ_head);
281 occ->bb_has_division = true;
282 occ->num_divisions++;
286 /* Compute the number of divisions that postdominate each block in OCC and
290 compute_merit (struct occurrence *occ)
292 struct occurrence *occ_child;
293 basic_block dom = occ->bb;
295 for (occ_child = occ->children; occ_child; occ_child = occ_child->next)
298 if (occ_child->children)
299 compute_merit (occ_child);
302 bb = single_noncomplex_succ (dom);
306 if (dominated_by_p (CDI_POST_DOMINATORS, bb, occ_child->bb))
307 occ->num_divisions += occ_child->num_divisions;
312 /* Return whether USE_STMT is a floating-point division by DEF. */
314 is_division_by (gimple use_stmt, tree def)
316 return is_gimple_assign (use_stmt)
317 && gimple_assign_rhs_code (use_stmt) == RDIV_EXPR
318 && gimple_assign_rhs2 (use_stmt) == def
319 /* Do not recognize x / x as valid division, as we are getting
320 confused later by replacing all immediate uses x in such
322 && gimple_assign_rhs1 (use_stmt) != def;
325 /* Walk the subset of the dominator tree rooted at OCC, setting the
326 RECIP_DEF field to a definition of 1.0 / DEF that can be used in
327 the given basic block. The field may be left NULL, of course,
328 if it is not possible or profitable to do the optimization.
330 DEF_BSI is an iterator pointing at the statement defining DEF.
331 If RECIP_DEF is set, a dominator already has a computation that can
335 insert_reciprocals (gimple_stmt_iterator *def_gsi, struct occurrence *occ,
336 tree def, tree recip_def, int threshold)
340 gimple_stmt_iterator gsi;
341 struct occurrence *occ_child;
344 && (occ->bb_has_division || !flag_trapping_math)
345 && occ->num_divisions >= threshold)
347 /* Make a variable with the replacement and substitute it. */
348 type = TREE_TYPE (def);
349 recip_def = make_rename_temp (type, "reciptmp");
350 new_stmt = gimple_build_assign_with_ops (RDIV_EXPR, recip_def,
351 build_one_cst (type), def);
353 if (occ->bb_has_division)
355 /* Case 1: insert before an existing division. */
356 gsi = gsi_after_labels (occ->bb);
357 while (!gsi_end_p (gsi) && !is_division_by (gsi_stmt (gsi), def))
360 gsi_insert_before (&gsi, new_stmt, GSI_SAME_STMT);
362 else if (def_gsi && occ->bb == def_gsi->bb)
364 /* Case 2: insert right after the definition. Note that this will
365 never happen if the definition statement can throw, because in
366 that case the sole successor of the statement's basic block will
367 dominate all the uses as well. */
368 gsi_insert_after (def_gsi, new_stmt, GSI_NEW_STMT);
372 /* Case 3: insert in a basic block not containing defs/uses. */
373 gsi = gsi_after_labels (occ->bb);
374 gsi_insert_before (&gsi, new_stmt, GSI_SAME_STMT);
377 reciprocal_stats.rdivs_inserted++;
379 occ->recip_def_stmt = new_stmt;
382 occ->recip_def = recip_def;
383 for (occ_child = occ->children; occ_child; occ_child = occ_child->next)
384 insert_reciprocals (def_gsi, occ_child, def, recip_def, threshold);
388 /* Replace the division at USE_P with a multiplication by the reciprocal, if
392 replace_reciprocal (use_operand_p use_p)
394 gimple use_stmt = USE_STMT (use_p);
395 basic_block bb = gimple_bb (use_stmt);
396 struct occurrence *occ = (struct occurrence *) bb->aux;
398 if (optimize_bb_for_speed_p (bb)
399 && occ->recip_def && use_stmt != occ->recip_def_stmt)
401 gimple_assign_set_rhs_code (use_stmt, MULT_EXPR);
402 SET_USE (use_p, occ->recip_def);
403 fold_stmt_inplace (use_stmt);
404 update_stmt (use_stmt);
409 /* Free OCC and return one more "struct occurrence" to be freed. */
411 static struct occurrence *
412 free_bb (struct occurrence *occ)
414 struct occurrence *child, *next;
416 /* First get the two pointers hanging off OCC. */
418 child = occ->children;
420 pool_free (occ_pool, occ);
422 /* Now ensure that we don't recurse unless it is necessary. */
428 next = free_bb (next);
435 /* Look for floating-point divisions among DEF's uses, and try to
436 replace them by multiplications with the reciprocal. Add
437 as many statements computing the reciprocal as needed.
439 DEF must be a GIMPLE register of a floating-point type. */
442 execute_cse_reciprocals_1 (gimple_stmt_iterator *def_gsi, tree def)
445 imm_use_iterator use_iter;
446 struct occurrence *occ;
447 int count = 0, threshold;
449 gcc_assert (FLOAT_TYPE_P (TREE_TYPE (def)) && is_gimple_reg (def));
451 FOR_EACH_IMM_USE_FAST (use_p, use_iter, def)
453 gimple use_stmt = USE_STMT (use_p);
454 if (is_division_by (use_stmt, def))
456 register_division_in (gimple_bb (use_stmt));
461 /* Do the expensive part only if we can hope to optimize something. */
462 threshold = targetm.min_divisions_for_recip_mul (TYPE_MODE (TREE_TYPE (def)));
463 if (count >= threshold)
466 for (occ = occ_head; occ; occ = occ->next)
469 insert_reciprocals (def_gsi, occ, def, NULL, threshold);
472 FOR_EACH_IMM_USE_STMT (use_stmt, use_iter, def)
474 if (is_division_by (use_stmt, def))
476 FOR_EACH_IMM_USE_ON_STMT (use_p, use_iter)
477 replace_reciprocal (use_p);
482 for (occ = occ_head; occ; )
489 gate_cse_reciprocals (void)
491 return optimize && flag_reciprocal_math;
494 /* Go through all the floating-point SSA_NAMEs, and call
495 execute_cse_reciprocals_1 on each of them. */
497 execute_cse_reciprocals (void)
502 occ_pool = create_alloc_pool ("dominators for recip",
503 sizeof (struct occurrence),
504 n_basic_blocks / 3 + 1);
506 memset (&reciprocal_stats, 0, sizeof (reciprocal_stats));
507 calculate_dominance_info (CDI_DOMINATORS);
508 calculate_dominance_info (CDI_POST_DOMINATORS);
510 #ifdef ENABLE_CHECKING
512 gcc_assert (!bb->aux);
515 for (arg = DECL_ARGUMENTS (cfun->decl); arg; arg = DECL_CHAIN (arg))
516 if (gimple_default_def (cfun, arg)
517 && FLOAT_TYPE_P (TREE_TYPE (arg))
518 && is_gimple_reg (arg))
519 execute_cse_reciprocals_1 (NULL, gimple_default_def (cfun, arg));
523 gimple_stmt_iterator gsi;
527 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
529 phi = gsi_stmt (gsi);
530 def = PHI_RESULT (phi);
531 if (FLOAT_TYPE_P (TREE_TYPE (def))
532 && is_gimple_reg (def))
533 execute_cse_reciprocals_1 (NULL, def);
536 for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi))
538 gimple stmt = gsi_stmt (gsi);
540 if (gimple_has_lhs (stmt)
541 && (def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF)) != NULL
542 && FLOAT_TYPE_P (TREE_TYPE (def))
543 && TREE_CODE (def) == SSA_NAME)
544 execute_cse_reciprocals_1 (&gsi, def);
547 if (optimize_bb_for_size_p (bb))
550 /* Scan for a/func(b) and convert it to reciprocal a*rfunc(b). */
551 for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi))
553 gimple stmt = gsi_stmt (gsi);
556 if (is_gimple_assign (stmt)
557 && gimple_assign_rhs_code (stmt) == RDIV_EXPR)
559 tree arg1 = gimple_assign_rhs2 (stmt);
562 if (TREE_CODE (arg1) != SSA_NAME)
565 stmt1 = SSA_NAME_DEF_STMT (arg1);
567 if (is_gimple_call (stmt1)
568 && gimple_call_lhs (stmt1)
569 && (fndecl = gimple_call_fndecl (stmt1))
570 && (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
571 || DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD))
573 enum built_in_function code;
578 code = DECL_FUNCTION_CODE (fndecl);
579 md_code = DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD;
581 fndecl = targetm.builtin_reciprocal (code, md_code, false);
585 /* Check that all uses of the SSA name are divisions,
586 otherwise replacing the defining statement will do
589 FOR_EACH_IMM_USE_FAST (use_p, ui, arg1)
591 gimple stmt2 = USE_STMT (use_p);
592 if (is_gimple_debug (stmt2))
594 if (!is_gimple_assign (stmt2)
595 || gimple_assign_rhs_code (stmt2) != RDIV_EXPR
596 || gimple_assign_rhs1 (stmt2) == arg1
597 || gimple_assign_rhs2 (stmt2) != arg1)
606 gimple_replace_lhs (stmt1, arg1);
607 gimple_call_set_fndecl (stmt1, fndecl);
609 reciprocal_stats.rfuncs_inserted++;
611 FOR_EACH_IMM_USE_STMT (stmt, ui, arg1)
613 gimple_assign_set_rhs_code (stmt, MULT_EXPR);
614 fold_stmt_inplace (stmt);
622 statistics_counter_event (cfun, "reciprocal divs inserted",
623 reciprocal_stats.rdivs_inserted);
624 statistics_counter_event (cfun, "reciprocal functions inserted",
625 reciprocal_stats.rfuncs_inserted);
627 free_dominance_info (CDI_DOMINATORS);
628 free_dominance_info (CDI_POST_DOMINATORS);
629 free_alloc_pool (occ_pool);
633 struct gimple_opt_pass pass_cse_reciprocals =
638 gate_cse_reciprocals, /* gate */
639 execute_cse_reciprocals, /* execute */
642 0, /* static_pass_number */
644 PROP_ssa, /* properties_required */
645 0, /* properties_provided */
646 0, /* properties_destroyed */
647 0, /* todo_flags_start */
648 TODO_update_ssa | TODO_verify_ssa
649 | TODO_verify_stmts /* todo_flags_finish */
653 /* Records an occurrence at statement USE_STMT in the vector of trees
654 STMTS if it is dominated by *TOP_BB or dominates it or this basic block
655 is not yet initialized. Returns true if the occurrence was pushed on
656 the vector. Adjusts *TOP_BB to be the basic block dominating all
657 statements in the vector. */
660 maybe_record_sincos (VEC(gimple, heap) **stmts,
661 basic_block *top_bb, gimple use_stmt)
663 basic_block use_bb = gimple_bb (use_stmt);
665 && (*top_bb == use_bb
666 || dominated_by_p (CDI_DOMINATORS, use_bb, *top_bb)))
667 VEC_safe_push (gimple, heap, *stmts, use_stmt);
669 || dominated_by_p (CDI_DOMINATORS, *top_bb, use_bb))
671 VEC_safe_push (gimple, heap, *stmts, use_stmt);
680 /* Look for sin, cos and cexpi calls with the same argument NAME and
681 create a single call to cexpi CSEing the result in this case.
682 We first walk over all immediate uses of the argument collecting
683 statements that we can CSE in a vector and in a second pass replace
684 the statement rhs with a REALPART or IMAGPART expression on the
685 result of the cexpi call we insert before the use statement that
686 dominates all other candidates. */
689 execute_cse_sincos_1 (tree name)
691 gimple_stmt_iterator gsi;
692 imm_use_iterator use_iter;
693 tree fndecl, res, type;
694 gimple def_stmt, use_stmt, stmt;
695 int seen_cos = 0, seen_sin = 0, seen_cexpi = 0;
696 VEC(gimple, heap) *stmts = NULL;
697 basic_block top_bb = NULL;
699 bool cfg_changed = false;
701 type = TREE_TYPE (name);
702 FOR_EACH_IMM_USE_STMT (use_stmt, use_iter, name)
704 if (gimple_code (use_stmt) != GIMPLE_CALL
705 || !gimple_call_lhs (use_stmt)
706 || !(fndecl = gimple_call_fndecl (use_stmt))
707 || DECL_BUILT_IN_CLASS (fndecl) != BUILT_IN_NORMAL)
710 switch (DECL_FUNCTION_CODE (fndecl))
712 CASE_FLT_FN (BUILT_IN_COS):
713 seen_cos |= maybe_record_sincos (&stmts, &top_bb, use_stmt) ? 1 : 0;
716 CASE_FLT_FN (BUILT_IN_SIN):
717 seen_sin |= maybe_record_sincos (&stmts, &top_bb, use_stmt) ? 1 : 0;
720 CASE_FLT_FN (BUILT_IN_CEXPI):
721 seen_cexpi |= maybe_record_sincos (&stmts, &top_bb, use_stmt) ? 1 : 0;
728 if (seen_cos + seen_sin + seen_cexpi <= 1)
730 VEC_free(gimple, heap, stmts);
734 /* Simply insert cexpi at the beginning of top_bb but not earlier than
735 the name def statement. */
736 fndecl = mathfn_built_in (type, BUILT_IN_CEXPI);
739 res = create_tmp_reg (TREE_TYPE (TREE_TYPE (fndecl)), "sincostmp");
740 stmt = gimple_build_call (fndecl, 1, name);
741 res = make_ssa_name (res, stmt);
742 gimple_call_set_lhs (stmt, res);
744 def_stmt = SSA_NAME_DEF_STMT (name);
745 if (!SSA_NAME_IS_DEFAULT_DEF (name)
746 && gimple_code (def_stmt) != GIMPLE_PHI
747 && gimple_bb (def_stmt) == top_bb)
749 gsi = gsi_for_stmt (def_stmt);
750 gsi_insert_after (&gsi, stmt, GSI_SAME_STMT);
754 gsi = gsi_after_labels (top_bb);
755 gsi_insert_before (&gsi, stmt, GSI_SAME_STMT);
758 sincos_stats.inserted++;
760 /* And adjust the recorded old call sites. */
761 for (i = 0; VEC_iterate(gimple, stmts, i, use_stmt); ++i)
764 fndecl = gimple_call_fndecl (use_stmt);
766 switch (DECL_FUNCTION_CODE (fndecl))
768 CASE_FLT_FN (BUILT_IN_COS):
769 rhs = fold_build1 (REALPART_EXPR, type, res);
772 CASE_FLT_FN (BUILT_IN_SIN):
773 rhs = fold_build1 (IMAGPART_EXPR, type, res);
776 CASE_FLT_FN (BUILT_IN_CEXPI):
784 /* Replace call with a copy. */
785 stmt = gimple_build_assign (gimple_call_lhs (use_stmt), rhs);
787 gsi = gsi_for_stmt (use_stmt);
788 gsi_replace (&gsi, stmt, true);
789 if (gimple_purge_dead_eh_edges (gimple_bb (stmt)))
793 VEC_free(gimple, heap, stmts);
798 /* To evaluate powi(x,n), the floating point value x raised to the
799 constant integer exponent n, we use a hybrid algorithm that
800 combines the "window method" with look-up tables. For an
801 introduction to exponentiation algorithms and "addition chains",
802 see section 4.6.3, "Evaluation of Powers" of Donald E. Knuth,
803 "Seminumerical Algorithms", Vol. 2, "The Art of Computer Programming",
804 3rd Edition, 1998, and Daniel M. Gordon, "A Survey of Fast Exponentiation
805 Methods", Journal of Algorithms, Vol. 27, pp. 129-146, 1998. */
807 /* Provide a default value for POWI_MAX_MULTS, the maximum number of
808 multiplications to inline before calling the system library's pow
809 function. powi(x,n) requires at worst 2*bits(n)-2 multiplications,
810 so this default never requires calling pow, powf or powl. */
812 #ifndef POWI_MAX_MULTS
813 #define POWI_MAX_MULTS (2*HOST_BITS_PER_WIDE_INT-2)
816 /* The size of the "optimal power tree" lookup table. All
817 exponents less than this value are simply looked up in the
818 powi_table below. This threshold is also used to size the
819 cache of pseudo registers that hold intermediate results. */
820 #define POWI_TABLE_SIZE 256
822 /* The size, in bits of the window, used in the "window method"
823 exponentiation algorithm. This is equivalent to a radix of
824 (1<<POWI_WINDOW_SIZE) in the corresponding "m-ary method". */
825 #define POWI_WINDOW_SIZE 3
827 /* The following table is an efficient representation of an
828 "optimal power tree". For each value, i, the corresponding
829 value, j, in the table states than an optimal evaluation
830 sequence for calculating pow(x,i) can be found by evaluating
831 pow(x,j)*pow(x,i-j). An optimal power tree for the first
832 100 integers is given in Knuth's "Seminumerical algorithms". */
834 static const unsigned char powi_table[POWI_TABLE_SIZE] =
836 0, 1, 1, 2, 2, 3, 3, 4, /* 0 - 7 */
837 4, 6, 5, 6, 6, 10, 7, 9, /* 8 - 15 */
838 8, 16, 9, 16, 10, 12, 11, 13, /* 16 - 23 */
839 12, 17, 13, 18, 14, 24, 15, 26, /* 24 - 31 */
840 16, 17, 17, 19, 18, 33, 19, 26, /* 32 - 39 */
841 20, 25, 21, 40, 22, 27, 23, 44, /* 40 - 47 */
842 24, 32, 25, 34, 26, 29, 27, 44, /* 48 - 55 */
843 28, 31, 29, 34, 30, 60, 31, 36, /* 56 - 63 */
844 32, 64, 33, 34, 34, 46, 35, 37, /* 64 - 71 */
845 36, 65, 37, 50, 38, 48, 39, 69, /* 72 - 79 */
846 40, 49, 41, 43, 42, 51, 43, 58, /* 80 - 87 */
847 44, 64, 45, 47, 46, 59, 47, 76, /* 88 - 95 */
848 48, 65, 49, 66, 50, 67, 51, 66, /* 96 - 103 */
849 52, 70, 53, 74, 54, 104, 55, 74, /* 104 - 111 */
850 56, 64, 57, 69, 58, 78, 59, 68, /* 112 - 119 */
851 60, 61, 61, 80, 62, 75, 63, 68, /* 120 - 127 */
852 64, 65, 65, 128, 66, 129, 67, 90, /* 128 - 135 */
853 68, 73, 69, 131, 70, 94, 71, 88, /* 136 - 143 */
854 72, 128, 73, 98, 74, 132, 75, 121, /* 144 - 151 */
855 76, 102, 77, 124, 78, 132, 79, 106, /* 152 - 159 */
856 80, 97, 81, 160, 82, 99, 83, 134, /* 160 - 167 */
857 84, 86, 85, 95, 86, 160, 87, 100, /* 168 - 175 */
858 88, 113, 89, 98, 90, 107, 91, 122, /* 176 - 183 */
859 92, 111, 93, 102, 94, 126, 95, 150, /* 184 - 191 */
860 96, 128, 97, 130, 98, 133, 99, 195, /* 192 - 199 */
861 100, 128, 101, 123, 102, 164, 103, 138, /* 200 - 207 */
862 104, 145, 105, 146, 106, 109, 107, 149, /* 208 - 215 */
863 108, 200, 109, 146, 110, 170, 111, 157, /* 216 - 223 */
864 112, 128, 113, 130, 114, 182, 115, 132, /* 224 - 231 */
865 116, 200, 117, 132, 118, 158, 119, 206, /* 232 - 239 */
866 120, 240, 121, 162, 122, 147, 123, 152, /* 240 - 247 */
867 124, 166, 125, 214, 126, 138, 127, 153, /* 248 - 255 */
871 /* Return the number of multiplications required to calculate
872 powi(x,n) where n is less than POWI_TABLE_SIZE. This is a
873 subroutine of powi_cost. CACHE is an array indicating
874 which exponents have already been calculated. */
877 powi_lookup_cost (unsigned HOST_WIDE_INT n, bool *cache)
879 /* If we've already calculated this exponent, then this evaluation
880 doesn't require any additional multiplications. */
885 return powi_lookup_cost (n - powi_table[n], cache)
886 + powi_lookup_cost (powi_table[n], cache) + 1;
889 /* Return the number of multiplications required to calculate
890 powi(x,n) for an arbitrary x, given the exponent N. This
891 function needs to be kept in sync with powi_as_mults below. */
894 powi_cost (HOST_WIDE_INT n)
896 bool cache[POWI_TABLE_SIZE];
897 unsigned HOST_WIDE_INT digit;
898 unsigned HOST_WIDE_INT val;
904 /* Ignore the reciprocal when calculating the cost. */
905 val = (n < 0) ? -n : n;
907 /* Initialize the exponent cache. */
908 memset (cache, 0, POWI_TABLE_SIZE * sizeof (bool));
913 while (val >= POWI_TABLE_SIZE)
917 digit = val & ((1 << POWI_WINDOW_SIZE) - 1);
918 result += powi_lookup_cost (digit, cache)
919 + POWI_WINDOW_SIZE + 1;
920 val >>= POWI_WINDOW_SIZE;
929 return result + powi_lookup_cost (val, cache);
932 /* Recursive subroutine of powi_as_mults. This function takes the
933 array, CACHE, of already calculated exponents and an exponent N and
934 returns a tree that corresponds to CACHE[1]**N, with type TYPE. */
937 powi_as_mults_1 (gimple_stmt_iterator *gsi, location_t loc, tree type,
938 HOST_WIDE_INT n, tree *cache, tree target)
940 tree op0, op1, ssa_target;
941 unsigned HOST_WIDE_INT digit;
944 if (n < POWI_TABLE_SIZE && cache[n])
947 ssa_target = make_ssa_name (target, NULL);
949 if (n < POWI_TABLE_SIZE)
951 cache[n] = ssa_target;
952 op0 = powi_as_mults_1 (gsi, loc, type, n - powi_table[n], cache, target);
953 op1 = powi_as_mults_1 (gsi, loc, type, powi_table[n], cache, target);
957 digit = n & ((1 << POWI_WINDOW_SIZE) - 1);
958 op0 = powi_as_mults_1 (gsi, loc, type, n - digit, cache, target);
959 op1 = powi_as_mults_1 (gsi, loc, type, digit, cache, target);
963 op0 = powi_as_mults_1 (gsi, loc, type, n >> 1, cache, target);
967 mult_stmt = gimple_build_assign_with_ops (MULT_EXPR, ssa_target, op0, op1);
968 gimple_set_location (mult_stmt, loc);
969 gsi_insert_before (gsi, mult_stmt, GSI_SAME_STMT);
974 /* Convert ARG0**N to a tree of multiplications of ARG0 with itself.
975 This function needs to be kept in sync with powi_cost above. */
978 powi_as_mults (gimple_stmt_iterator *gsi, location_t loc,
979 tree arg0, HOST_WIDE_INT n)
981 tree cache[POWI_TABLE_SIZE], result, type = TREE_TYPE (arg0), target;
985 return build_real (type, dconst1);
987 memset (cache, 0, sizeof (cache));
990 target = create_tmp_reg (type, "powmult");
991 add_referenced_var (target);
993 result = powi_as_mults_1 (gsi, loc, type, (n < 0) ? -n : n, cache, target);
998 /* If the original exponent was negative, reciprocate the result. */
999 target = make_ssa_name (target, NULL);
1000 div_stmt = gimple_build_assign_with_ops (RDIV_EXPR, target,
1001 build_real (type, dconst1),
1003 gimple_set_location (div_stmt, loc);
1004 gsi_insert_before (gsi, div_stmt, GSI_SAME_STMT);
1009 /* ARG0 and N are the two arguments to a powi builtin in GSI with
1010 location info LOC. If the arguments are appropriate, create an
1011 equivalent sequence of statements prior to GSI using an optimal
1012 number of multiplications, and return an expession holding the
1016 gimple_expand_builtin_powi (gimple_stmt_iterator *gsi, location_t loc,
1017 tree arg0, HOST_WIDE_INT n)
1019 /* Avoid largest negative number. */
1021 && ((n >= -1 && n <= 2)
1022 || (optimize_function_for_speed_p (cfun)
1023 && powi_cost (n) <= POWI_MAX_MULTS)))
1024 return powi_as_mults (gsi, loc, arg0, n);
1029 /* Build a gimple call statement that calls FN with argument ARG.
1030 Set the lhs of the call statement to a fresh SSA name for
1031 variable VAR. If VAR is NULL, first allocate it. Insert the
1032 statement prior to GSI's current position, and return the fresh
1036 build_and_insert_call (gimple_stmt_iterator *gsi, location_t loc,
1037 tree *var, tree fn, tree arg)
1044 *var = create_tmp_reg (TREE_TYPE (arg), "powroot");
1045 add_referenced_var (*var);
1048 call_stmt = gimple_build_call (fn, 1, arg);
1049 ssa_target = make_ssa_name (*var, NULL);
1050 gimple_set_lhs (call_stmt, ssa_target);
1051 gimple_set_location (call_stmt, loc);
1052 gsi_insert_before (gsi, call_stmt, GSI_SAME_STMT);
1057 /* Build a gimple binary operation with the given CODE and arguments
1058 ARG0, ARG1, assigning the result to a new SSA name for variable
1059 TARGET. Insert the statement prior to GSI's current position, and
1060 return the fresh SSA name.*/
1063 build_and_insert_binop (gimple_stmt_iterator *gsi, location_t loc,
1064 tree target, enum tree_code code, tree arg0, tree arg1)
1066 tree result = make_ssa_name (target, NULL);
1067 gimple stmt = gimple_build_assign_with_ops (code, result, arg0, arg1);
1068 gimple_set_location (stmt, loc);
1069 gsi_insert_before (gsi, stmt, GSI_SAME_STMT);
1073 /* Build a gimple reference operation with the given CODE and argument
1074 ARG, assigning the result to a new SSA name for variable TARGET.
1075 Insert the statement prior to GSI's current position, and return
1076 the fresh SSA name. */
1079 build_and_insert_ref (gimple_stmt_iterator *gsi, location_t loc, tree type,
1080 tree target, enum tree_code code, tree arg0)
1082 tree result = make_ssa_name (target, NULL);
1083 gimple stmt = gimple_build_assign (result, build1 (code, type, arg0));
1084 gimple_set_location (stmt, loc);
1085 gsi_insert_before (gsi, stmt, GSI_SAME_STMT);
1089 /* ARG0 and ARG1 are the two arguments to a pow builtin call in GSI
1090 with location info LOC. If possible, create an equivalent and
1091 less expensive sequence of statements prior to GSI, and return an
1092 expession holding the result. */
1095 gimple_expand_builtin_pow (gimple_stmt_iterator *gsi, location_t loc,
1096 tree arg0, tree arg1)
1098 REAL_VALUE_TYPE c, cint, dconst1_4, dconst3_4, dconst1_3, dconst1_6;
1099 REAL_VALUE_TYPE c2, dconst3;
1101 tree type, sqrtfn, cbrtfn, sqrt_arg0, sqrt_sqrt, result, cbrt_x, powi_cbrt_x;
1102 tree target = NULL_TREE;
1103 enum machine_mode mode;
1104 bool hw_sqrt_exists;
1106 /* If the exponent isn't a constant, there's nothing of interest
1108 if (TREE_CODE (arg1) != REAL_CST)
1111 /* If the exponent is equivalent to an integer, expand to an optimal
1112 multiplication sequence when profitable. */
1113 c = TREE_REAL_CST (arg1);
1114 n = real_to_integer (&c);
1115 real_from_integer (&cint, VOIDmode, n, n < 0 ? -1 : 0, 0);
1117 if (real_identical (&c, &cint)
1118 && ((n >= -1 && n <= 2)
1119 || (flag_unsafe_math_optimizations
1120 && optimize_insn_for_speed_p ()
1121 && powi_cost (n) <= POWI_MAX_MULTS)))
1122 return gimple_expand_builtin_powi (gsi, loc, arg0, n);
1124 /* Attempt various optimizations using sqrt and cbrt. */
1125 type = TREE_TYPE (arg0);
1126 mode = TYPE_MODE (type);
1127 sqrtfn = mathfn_built_in (type, BUILT_IN_SQRT);
1129 /* Optimize pow(x,0.5) = sqrt(x). This replacement is always safe
1130 unless signed zeros must be maintained. pow(-0,0.5) = +0, while
1133 && REAL_VALUES_EQUAL (c, dconsthalf)
1134 && !HONOR_SIGNED_ZEROS (mode))
1135 return build_and_insert_call (gsi, loc, &target, sqrtfn, arg0);
1137 /* Optimize pow(x,0.25) = sqrt(sqrt(x)). Assume on most machines that
1138 a builtin sqrt instruction is smaller than a call to pow with 0.25,
1139 so do this optimization even if -Os. Don't do this optimization
1140 if we don't have a hardware sqrt insn. */
1141 dconst1_4 = dconst1;
1142 SET_REAL_EXP (&dconst1_4, REAL_EXP (&dconst1_4) - 2);
1143 hw_sqrt_exists = optab_handler (sqrt_optab, mode) != CODE_FOR_nothing;
1145 if (flag_unsafe_math_optimizations
1147 && REAL_VALUES_EQUAL (c, dconst1_4)
1151 sqrt_arg0 = build_and_insert_call (gsi, loc, &target, sqrtfn, arg0);
1154 return build_and_insert_call (gsi, loc, &target, sqrtfn, sqrt_arg0);
1157 /* Optimize pow(x,0.75) = sqrt(x) * sqrt(sqrt(x)) unless we are
1158 optimizing for space. Don't do this optimization if we don't have
1159 a hardware sqrt insn. */
1160 real_from_integer (&dconst3_4, VOIDmode, 3, 0, 0);
1161 SET_REAL_EXP (&dconst3_4, REAL_EXP (&dconst3_4) - 2);
1163 if (flag_unsafe_math_optimizations
1165 && optimize_function_for_speed_p (cfun)
1166 && REAL_VALUES_EQUAL (c, dconst3_4)
1170 sqrt_arg0 = build_and_insert_call (gsi, loc, &target, sqrtfn, arg0);
1173 sqrt_sqrt = build_and_insert_call (gsi, loc, &target, sqrtfn, sqrt_arg0);
1175 /* sqrt(x) * sqrt(sqrt(x)) */
1176 return build_and_insert_binop (gsi, loc, target, MULT_EXPR,
1177 sqrt_arg0, sqrt_sqrt);
1180 /* Optimize pow(x,1./3.) = cbrt(x). This requires unsafe math
1181 optimizations since 1./3. is not exactly representable. If x
1182 is negative and finite, the correct value of pow(x,1./3.) is
1183 a NaN with the "invalid" exception raised, because the value
1184 of 1./3. actually has an even denominator. The correct value
1185 of cbrt(x) is a negative real value. */
1186 cbrtfn = mathfn_built_in (type, BUILT_IN_CBRT);
1187 dconst1_3 = real_value_truncate (mode, dconst_third ());
1189 if (flag_unsafe_math_optimizations
1191 && (gimple_val_nonnegative_real_p (arg0) || !HONOR_NANS (mode))
1192 && REAL_VALUES_EQUAL (c, dconst1_3))
1193 return build_and_insert_call (gsi, loc, &target, cbrtfn, arg0);
1195 /* Optimize pow(x,1./6.) = cbrt(sqrt(x)). Don't do this optimization
1196 if we don't have a hardware sqrt insn. */
1197 dconst1_6 = dconst1_3;
1198 SET_REAL_EXP (&dconst1_6, REAL_EXP (&dconst1_6) - 1);
1200 if (flag_unsafe_math_optimizations
1203 && (gimple_val_nonnegative_real_p (arg0) || !HONOR_NANS (mode))
1204 && optimize_function_for_speed_p (cfun)
1206 && REAL_VALUES_EQUAL (c, dconst1_6))
1209 sqrt_arg0 = build_and_insert_call (gsi, loc, &target, sqrtfn, arg0);
1212 return build_and_insert_call (gsi, loc, &target, cbrtfn, sqrt_arg0);
1215 /* Optimize pow(x,c), where n = 2c for some nonzero integer n, into
1217 sqrt(x) * powi(x, n/2), n > 0;
1218 1.0 / (sqrt(x) * powi(x, abs(n/2))), n < 0.
1220 Do not calculate the powi factor when n/2 = 0. */
1221 real_arithmetic (&c2, MULT_EXPR, &c, &dconst2);
1222 n = real_to_integer (&c2);
1223 real_from_integer (&cint, VOIDmode, n, n < 0 ? -1 : 0, 0);
1225 if (flag_unsafe_math_optimizations
1227 && real_identical (&c2, &cint))
1229 tree powi_x_ndiv2 = NULL_TREE;
1231 /* Attempt to fold powi(arg0, abs(n/2)) into multiplies. If not
1232 possible or profitable, give up. Skip the degenerate case when
1233 n is 1 or -1, where the result is always 1. */
1236 powi_x_ndiv2 = gimple_expand_builtin_powi (gsi, loc, arg0, abs(n/2));
1241 /* Calculate sqrt(x). When n is not 1 or -1, multiply it by the
1242 result of the optimal multiply sequence just calculated. */
1243 sqrt_arg0 = build_and_insert_call (gsi, loc, &target, sqrtfn, arg0);
1248 result = build_and_insert_binop (gsi, loc, target, MULT_EXPR,
1249 sqrt_arg0, powi_x_ndiv2);
1251 /* If n is negative, reciprocate the result. */
1253 result = build_and_insert_binop (gsi, loc, target, RDIV_EXPR,
1254 build_real (type, dconst1), result);
1258 /* Optimize pow(x,c), where 3c = n for some nonzero integer n, into
1260 powi(x, n/3) * powi(cbrt(x), n%3), n > 0;
1261 1.0 / (powi(x, abs(n)/3) * powi(cbrt(x), abs(n)%3)), n < 0.
1263 Do not calculate the first factor when n/3 = 0. As cbrt(x) is
1264 different from pow(x, 1./3.) due to rounding and behavior with
1265 negative x, we need to constrain this transformation to unsafe
1266 math and positive x or finite math. */
1267 real_from_integer (&dconst3, VOIDmode, 3, 0, 0);
1268 real_arithmetic (&c2, MULT_EXPR, &c, &dconst3);
1269 real_round (&c2, mode, &c2);
1270 n = real_to_integer (&c2);
1271 real_from_integer (&cint, VOIDmode, n, n < 0 ? -1 : 0, 0);
1272 real_arithmetic (&c2, RDIV_EXPR, &cint, &dconst3);
1273 real_convert (&c2, mode, &c2);
1275 if (flag_unsafe_math_optimizations
1277 && (gimple_val_nonnegative_real_p (arg0) || !HONOR_NANS (mode))
1278 && real_identical (&c2, &c)
1279 && optimize_function_for_speed_p (cfun)
1280 && powi_cost (n / 3) <= POWI_MAX_MULTS)
1282 tree powi_x_ndiv3 = NULL_TREE;
1284 /* Attempt to fold powi(arg0, abs(n/3)) into multiplies. If not
1285 possible or profitable, give up. Skip the degenerate case when
1286 abs(n) < 3, where the result is always 1. */
1289 powi_x_ndiv3 = gimple_expand_builtin_powi (gsi, loc, arg0,
1295 /* Calculate powi(cbrt(x), n%3). Don't use gimple_expand_builtin_powi
1296 as that creates an unnecessary variable. Instead, just produce
1297 either cbrt(x) or cbrt(x) * cbrt(x). */
1298 cbrt_x = build_and_insert_call (gsi, loc, &target, cbrtfn, arg0);
1300 if (abs (n) % 3 == 1)
1301 powi_cbrt_x = cbrt_x;
1303 powi_cbrt_x = build_and_insert_binop (gsi, loc, target, MULT_EXPR,
1306 /* Multiply the two subexpressions, unless powi(x,abs(n)/3) = 1. */
1308 result = powi_cbrt_x;
1310 result = build_and_insert_binop (gsi, loc, target, MULT_EXPR,
1311 powi_x_ndiv3, powi_cbrt_x);
1313 /* If n is negative, reciprocate the result. */
1315 result = build_and_insert_binop (gsi, loc, target, RDIV_EXPR,
1316 build_real (type, dconst1), result);
1321 /* No optimizations succeeded. */
1325 /* ARG is the argument to a cabs builtin call in GSI with location info
1326 LOC. Create a sequence of statements prior to GSI that calculates
1327 sqrt(R*R + I*I), where R and I are the real and imaginary components
1328 of ARG, respectively. Return an expression holding the result. */
1331 gimple_expand_builtin_cabs (gimple_stmt_iterator *gsi, location_t loc, tree arg)
1333 tree target, real_part, imag_part, addend1, addend2, sum, result;
1334 tree type = TREE_TYPE (TREE_TYPE (arg));
1335 tree sqrtfn = mathfn_built_in (type, BUILT_IN_SQRT);
1336 enum machine_mode mode = TYPE_MODE (type);
1338 if (!flag_unsafe_math_optimizations
1339 || !optimize_bb_for_speed_p (gimple_bb (gsi_stmt (*gsi)))
1341 || optab_handler (sqrt_optab, mode) == CODE_FOR_nothing)
1344 target = create_tmp_reg (type, "cabs");
1345 add_referenced_var (target);
1347 real_part = build_and_insert_ref (gsi, loc, type, target,
1348 REALPART_EXPR, arg);
1349 addend1 = build_and_insert_binop (gsi, loc, target, MULT_EXPR,
1350 real_part, real_part);
1351 imag_part = build_and_insert_ref (gsi, loc, type, target,
1352 IMAGPART_EXPR, arg);
1353 addend2 = build_and_insert_binop (gsi, loc, target, MULT_EXPR,
1354 imag_part, imag_part);
1355 sum = build_and_insert_binop (gsi, loc, target, PLUS_EXPR, addend1, addend2);
1356 result = build_and_insert_call (gsi, loc, &target, sqrtfn, sum);
1361 /* Go through all calls to sin, cos and cexpi and call execute_cse_sincos_1
1362 on the SSA_NAME argument of each of them. Also expand powi(x,n) into
1363 an optimal number of multiplies, when n is a constant. */
1366 execute_cse_sincos (void)
1369 bool cfg_changed = false;
1371 calculate_dominance_info (CDI_DOMINATORS);
1372 memset (&sincos_stats, 0, sizeof (sincos_stats));
1376 gimple_stmt_iterator gsi;
1378 for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi))
1380 gimple stmt = gsi_stmt (gsi);
1383 if (is_gimple_call (stmt)
1384 && gimple_call_lhs (stmt)
1385 && (fndecl = gimple_call_fndecl (stmt))
1386 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
1388 tree arg, arg0, arg1, result;
1392 switch (DECL_FUNCTION_CODE (fndecl))
1394 CASE_FLT_FN (BUILT_IN_COS):
1395 CASE_FLT_FN (BUILT_IN_SIN):
1396 CASE_FLT_FN (BUILT_IN_CEXPI):
1397 /* Make sure we have either sincos or cexp. */
1398 if (!TARGET_HAS_SINCOS && !TARGET_C99_FUNCTIONS)
1401 arg = gimple_call_arg (stmt, 0);
1402 if (TREE_CODE (arg) == SSA_NAME)
1403 cfg_changed |= execute_cse_sincos_1 (arg);
1406 CASE_FLT_FN (BUILT_IN_POW):
1407 arg0 = gimple_call_arg (stmt, 0);
1408 arg1 = gimple_call_arg (stmt, 1);
1410 loc = gimple_location (stmt);
1411 result = gimple_expand_builtin_pow (&gsi, loc, arg0, arg1);
1415 tree lhs = gimple_get_lhs (stmt);
1416 gimple new_stmt = gimple_build_assign (lhs, result);
1417 gimple_set_location (new_stmt, loc);
1418 unlink_stmt_vdef (stmt);
1419 gsi_replace (&gsi, new_stmt, true);
1423 CASE_FLT_FN (BUILT_IN_POWI):
1424 arg0 = gimple_call_arg (stmt, 0);
1425 arg1 = gimple_call_arg (stmt, 1);
1426 if (!host_integerp (arg1, 0))
1429 n = TREE_INT_CST_LOW (arg1);
1430 loc = gimple_location (stmt);
1431 result = gimple_expand_builtin_powi (&gsi, loc, arg0, n);
1435 tree lhs = gimple_get_lhs (stmt);
1436 gimple new_stmt = gimple_build_assign (lhs, result);
1437 gimple_set_location (new_stmt, loc);
1438 unlink_stmt_vdef (stmt);
1439 gsi_replace (&gsi, new_stmt, true);
1443 CASE_FLT_FN (BUILT_IN_CABS):
1444 arg0 = gimple_call_arg (stmt, 0);
1445 loc = gimple_location (stmt);
1446 result = gimple_expand_builtin_cabs (&gsi, loc, arg0);
1450 tree lhs = gimple_get_lhs (stmt);
1451 gimple new_stmt = gimple_build_assign (lhs, result);
1452 gimple_set_location (new_stmt, loc);
1453 unlink_stmt_vdef (stmt);
1454 gsi_replace (&gsi, new_stmt, true);
1464 statistics_counter_event (cfun, "sincos statements inserted",
1465 sincos_stats.inserted);
1467 free_dominance_info (CDI_DOMINATORS);
1468 return cfg_changed ? TODO_cleanup_cfg : 0;
1472 gate_cse_sincos (void)
1474 /* We no longer require either sincos or cexp, since powi expansion
1475 piggybacks on this pass. */
1479 struct gimple_opt_pass pass_cse_sincos =
1483 "sincos", /* name */
1484 gate_cse_sincos, /* gate */
1485 execute_cse_sincos, /* execute */
1488 0, /* static_pass_number */
1489 TV_NONE, /* tv_id */
1490 PROP_ssa, /* properties_required */
1491 0, /* properties_provided */
1492 0, /* properties_destroyed */
1493 0, /* todo_flags_start */
1494 TODO_update_ssa | TODO_verify_ssa
1495 | TODO_verify_stmts /* todo_flags_finish */
1499 /* A symbolic number is used to detect byte permutation and selection
1500 patterns. Therefore the field N contains an artificial number
1501 consisting of byte size markers:
1503 0 - byte has the value 0
1504 1..size - byte contains the content of the byte
1505 number indexed with that value minus one */
1507 struct symbolic_number {
1508 unsigned HOST_WIDEST_INT n;
1512 /* Perform a SHIFT or ROTATE operation by COUNT bits on symbolic
1513 number N. Return false if the requested operation is not permitted
1514 on a symbolic number. */
1517 do_shift_rotate (enum tree_code code,
1518 struct symbolic_number *n,
1524 /* Zero out the extra bits of N in order to avoid them being shifted
1525 into the significant bits. */
1526 if (n->size < (int)sizeof (HOST_WIDEST_INT))
1527 n->n &= ((unsigned HOST_WIDEST_INT)1 << (n->size * BITS_PER_UNIT)) - 1;
1538 n->n = (n->n << count) | (n->n >> ((n->size * BITS_PER_UNIT) - count));
1541 n->n = (n->n >> count) | (n->n << ((n->size * BITS_PER_UNIT) - count));
1546 /* Zero unused bits for size. */
1547 if (n->size < (int)sizeof (HOST_WIDEST_INT))
1548 n->n &= ((unsigned HOST_WIDEST_INT)1 << (n->size * BITS_PER_UNIT)) - 1;
1552 /* Perform sanity checking for the symbolic number N and the gimple
1556 verify_symbolic_number_p (struct symbolic_number *n, gimple stmt)
1560 lhs_type = gimple_expr_type (stmt);
1562 if (TREE_CODE (lhs_type) != INTEGER_TYPE)
1565 if (TYPE_PRECISION (lhs_type) != n->size * BITS_PER_UNIT)
1571 /* find_bswap_1 invokes itself recursively with N and tries to perform
1572 the operation given by the rhs of STMT on the result. If the
1573 operation could successfully be executed the function returns the
1574 tree expression of the source operand and NULL otherwise. */
1577 find_bswap_1 (gimple stmt, struct symbolic_number *n, int limit)
1579 enum tree_code code;
1580 tree rhs1, rhs2 = NULL;
1581 gimple rhs1_stmt, rhs2_stmt;
1583 enum gimple_rhs_class rhs_class;
1585 if (!limit || !is_gimple_assign (stmt))
1588 rhs1 = gimple_assign_rhs1 (stmt);
1590 if (TREE_CODE (rhs1) != SSA_NAME)
1593 code = gimple_assign_rhs_code (stmt);
1594 rhs_class = gimple_assign_rhs_class (stmt);
1595 rhs1_stmt = SSA_NAME_DEF_STMT (rhs1);
1597 if (rhs_class == GIMPLE_BINARY_RHS)
1598 rhs2 = gimple_assign_rhs2 (stmt);
1600 /* Handle unary rhs and binary rhs with integer constants as second
1603 if (rhs_class == GIMPLE_UNARY_RHS
1604 || (rhs_class == GIMPLE_BINARY_RHS
1605 && TREE_CODE (rhs2) == INTEGER_CST))
1607 if (code != BIT_AND_EXPR
1608 && code != LSHIFT_EXPR
1609 && code != RSHIFT_EXPR
1610 && code != LROTATE_EXPR
1611 && code != RROTATE_EXPR
1613 && code != CONVERT_EXPR)
1616 source_expr1 = find_bswap_1 (rhs1_stmt, n, limit - 1);
1618 /* If find_bswap_1 returned NULL STMT is a leaf node and we have
1619 to initialize the symbolic number. */
1622 /* Set up the symbolic number N by setting each byte to a
1623 value between 1 and the byte size of rhs1. The highest
1624 order byte is set to n->size and the lowest order
1626 n->size = TYPE_PRECISION (TREE_TYPE (rhs1));
1627 if (n->size % BITS_PER_UNIT != 0)
1629 n->size /= BITS_PER_UNIT;
1630 n->n = (sizeof (HOST_WIDEST_INT) < 8 ? 0 :
1631 (unsigned HOST_WIDEST_INT)0x08070605 << 32 | 0x04030201);
1633 if (n->size < (int)sizeof (HOST_WIDEST_INT))
1634 n->n &= ((unsigned HOST_WIDEST_INT)1 <<
1635 (n->size * BITS_PER_UNIT)) - 1;
1637 source_expr1 = rhs1;
1645 unsigned HOST_WIDEST_INT val = widest_int_cst_value (rhs2);
1646 unsigned HOST_WIDEST_INT tmp = val;
1648 /* Only constants masking full bytes are allowed. */
1649 for (i = 0; i < n->size; i++, tmp >>= BITS_PER_UNIT)
1650 if ((tmp & 0xff) != 0 && (tmp & 0xff) != 0xff)
1660 if (!do_shift_rotate (code, n, (int)TREE_INT_CST_LOW (rhs2)))
1667 type_size = TYPE_PRECISION (gimple_expr_type (stmt));
1668 if (type_size % BITS_PER_UNIT != 0)
1671 if (type_size / BITS_PER_UNIT < (int)(sizeof (HOST_WIDEST_INT)))
1673 /* If STMT casts to a smaller type mask out the bits not
1674 belonging to the target type. */
1675 n->n &= ((unsigned HOST_WIDEST_INT)1 << type_size) - 1;
1677 n->size = type_size / BITS_PER_UNIT;
1683 return verify_symbolic_number_p (n, stmt) ? source_expr1 : NULL;
1686 /* Handle binary rhs. */
1688 if (rhs_class == GIMPLE_BINARY_RHS)
1690 struct symbolic_number n1, n2;
1693 if (code != BIT_IOR_EXPR)
1696 if (TREE_CODE (rhs2) != SSA_NAME)
1699 rhs2_stmt = SSA_NAME_DEF_STMT (rhs2);
1704 source_expr1 = find_bswap_1 (rhs1_stmt, &n1, limit - 1);
1709 source_expr2 = find_bswap_1 (rhs2_stmt, &n2, limit - 1);
1711 if (source_expr1 != source_expr2
1712 || n1.size != n2.size)
1718 if (!verify_symbolic_number_p (n, stmt))
1725 return source_expr1;
1730 /* Check if STMT completes a bswap implementation consisting of ORs,
1731 SHIFTs and ANDs. Return the source tree expression on which the
1732 byte swap is performed and NULL if no bswap was found. */
1735 find_bswap (gimple stmt)
1737 /* The number which the find_bswap result should match in order to
1738 have a full byte swap. The number is shifted to the left according
1739 to the size of the symbolic number before using it. */
1740 unsigned HOST_WIDEST_INT cmp =
1741 sizeof (HOST_WIDEST_INT) < 8 ? 0 :
1742 (unsigned HOST_WIDEST_INT)0x01020304 << 32 | 0x05060708;
1744 struct symbolic_number n;
1748 /* The last parameter determines the depth search limit. It usually
1749 correlates directly to the number of bytes to be touched. We
1750 increase that number by three here in order to also
1751 cover signed -> unsigned converions of the src operand as can be seen
1752 in libgcc, and for initial shift/and operation of the src operand. */
1753 limit = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (gimple_expr_type (stmt)));
1754 limit += 1 + (int) ceil_log2 ((unsigned HOST_WIDE_INT) limit);
1755 source_expr = find_bswap_1 (stmt, &n, limit);
1760 /* Zero out the extra bits of N and CMP. */
1761 if (n.size < (int)sizeof (HOST_WIDEST_INT))
1763 unsigned HOST_WIDEST_INT mask =
1764 ((unsigned HOST_WIDEST_INT)1 << (n.size * BITS_PER_UNIT)) - 1;
1767 cmp >>= (sizeof (HOST_WIDEST_INT) - n.size) * BITS_PER_UNIT;
1770 /* A complete byte swap should make the symbolic number to start
1771 with the largest digit in the highest order byte. */
1778 /* Find manual byte swap implementations and turn them into a bswap
1779 builtin invokation. */
1782 execute_optimize_bswap (void)
1785 bool bswap32_p, bswap64_p;
1786 bool changed = false;
1787 tree bswap32_type = NULL_TREE, bswap64_type = NULL_TREE;
1789 if (BITS_PER_UNIT != 8)
1792 if (sizeof (HOST_WIDEST_INT) < 8)
1795 bswap32_p = (built_in_decls[BUILT_IN_BSWAP32]
1796 && optab_handler (bswap_optab, SImode) != CODE_FOR_nothing);
1797 bswap64_p = (built_in_decls[BUILT_IN_BSWAP64]
1798 && (optab_handler (bswap_optab, DImode) != CODE_FOR_nothing
1799 || (bswap32_p && word_mode == SImode)));
1801 if (!bswap32_p && !bswap64_p)
1804 /* Determine the argument type of the builtins. The code later on
1805 assumes that the return and argument type are the same. */
1808 tree fndecl = built_in_decls[BUILT_IN_BSWAP32];
1809 bswap32_type = TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (fndecl)));
1814 tree fndecl = built_in_decls[BUILT_IN_BSWAP64];
1815 bswap64_type = TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (fndecl)));
1818 memset (&bswap_stats, 0, sizeof (bswap_stats));
1822 gimple_stmt_iterator gsi;
1824 for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi))
1826 gimple stmt = gsi_stmt (gsi);
1827 tree bswap_src, bswap_type;
1829 tree fndecl = NULL_TREE;
1833 if (!is_gimple_assign (stmt)
1834 || gimple_assign_rhs_code (stmt) != BIT_IOR_EXPR)
1837 type_size = TYPE_PRECISION (gimple_expr_type (stmt));
1844 fndecl = built_in_decls[BUILT_IN_BSWAP32];
1845 bswap_type = bswap32_type;
1851 fndecl = built_in_decls[BUILT_IN_BSWAP64];
1852 bswap_type = bswap64_type;
1862 bswap_src = find_bswap (stmt);
1868 if (type_size == 32)
1869 bswap_stats.found_32bit++;
1871 bswap_stats.found_64bit++;
1873 bswap_tmp = bswap_src;
1875 /* Convert the src expression if necessary. */
1876 if (!useless_type_conversion_p (TREE_TYPE (bswap_tmp), bswap_type))
1878 gimple convert_stmt;
1880 bswap_tmp = create_tmp_var (bswap_type, "bswapsrc");
1881 add_referenced_var (bswap_tmp);
1882 bswap_tmp = make_ssa_name (bswap_tmp, NULL);
1884 convert_stmt = gimple_build_assign_with_ops (
1885 CONVERT_EXPR, bswap_tmp, bswap_src, NULL);
1886 gsi_insert_before (&gsi, convert_stmt, GSI_SAME_STMT);
1889 call = gimple_build_call (fndecl, 1, bswap_tmp);
1891 bswap_tmp = gimple_assign_lhs (stmt);
1893 /* Convert the result if necessary. */
1894 if (!useless_type_conversion_p (TREE_TYPE (bswap_tmp), bswap_type))
1896 gimple convert_stmt;
1898 bswap_tmp = create_tmp_var (bswap_type, "bswapdst");
1899 add_referenced_var (bswap_tmp);
1900 bswap_tmp = make_ssa_name (bswap_tmp, NULL);
1901 convert_stmt = gimple_build_assign_with_ops (
1902 CONVERT_EXPR, gimple_assign_lhs (stmt), bswap_tmp, NULL);
1903 gsi_insert_after (&gsi, convert_stmt, GSI_SAME_STMT);
1906 gimple_call_set_lhs (call, bswap_tmp);
1910 fprintf (dump_file, "%d bit bswap implementation found at: ",
1912 print_gimple_stmt (dump_file, stmt, 0, 0);
1915 gsi_insert_after (&gsi, call, GSI_SAME_STMT);
1916 gsi_remove (&gsi, true);
1920 statistics_counter_event (cfun, "32-bit bswap implementations found",
1921 bswap_stats.found_32bit);
1922 statistics_counter_event (cfun, "64-bit bswap implementations found",
1923 bswap_stats.found_64bit);
1925 return (changed ? TODO_update_ssa | TODO_verify_ssa
1926 | TODO_verify_stmts : 0);
1930 gate_optimize_bswap (void)
1932 return flag_expensive_optimizations && optimize;
1935 struct gimple_opt_pass pass_optimize_bswap =
1940 gate_optimize_bswap, /* gate */
1941 execute_optimize_bswap, /* execute */
1944 0, /* static_pass_number */
1945 TV_NONE, /* tv_id */
1946 PROP_ssa, /* properties_required */
1947 0, /* properties_provided */
1948 0, /* properties_destroyed */
1949 0, /* todo_flags_start */
1950 0 /* todo_flags_finish */
1954 /* Return true if RHS is a suitable operand for a widening multiplication.
1955 There are two cases:
1957 - RHS makes some value twice as wide. Store that value in *NEW_RHS_OUT
1958 if so, and store its type in *TYPE_OUT.
1960 - RHS is an integer constant. Store that value in *NEW_RHS_OUT if so,
1961 but leave *TYPE_OUT untouched. */
1964 is_widening_mult_rhs_p (tree rhs, tree *type_out, tree *new_rhs_out)
1967 tree type, type1, rhs1;
1968 enum tree_code rhs_code;
1970 if (TREE_CODE (rhs) == SSA_NAME)
1972 type = TREE_TYPE (rhs);
1973 stmt = SSA_NAME_DEF_STMT (rhs);
1974 if (!is_gimple_assign (stmt))
1977 rhs_code = gimple_assign_rhs_code (stmt);
1978 if (TREE_CODE (type) == INTEGER_TYPE
1979 ? !CONVERT_EXPR_CODE_P (rhs_code)
1980 : rhs_code != FIXED_CONVERT_EXPR)
1983 rhs1 = gimple_assign_rhs1 (stmt);
1984 type1 = TREE_TYPE (rhs1);
1985 if (TREE_CODE (type1) != TREE_CODE (type)
1986 || TYPE_PRECISION (type1) * 2 != TYPE_PRECISION (type))
1989 *new_rhs_out = rhs1;
1994 if (TREE_CODE (rhs) == INTEGER_CST)
2004 /* Return true if STMT performs a widening multiplication. If so,
2005 store the unwidened types of the operands in *TYPE1_OUT and *TYPE2_OUT
2006 respectively. Also fill *RHS1_OUT and *RHS2_OUT such that converting
2007 those operands to types *TYPE1_OUT and *TYPE2_OUT would give the
2008 operands of the multiplication. */
2011 is_widening_mult_p (gimple stmt,
2012 tree *type1_out, tree *rhs1_out,
2013 tree *type2_out, tree *rhs2_out)
2017 type = TREE_TYPE (gimple_assign_lhs (stmt));
2018 if (TREE_CODE (type) != INTEGER_TYPE
2019 && TREE_CODE (type) != FIXED_POINT_TYPE)
2022 if (!is_widening_mult_rhs_p (gimple_assign_rhs1 (stmt), type1_out, rhs1_out))
2025 if (!is_widening_mult_rhs_p (gimple_assign_rhs2 (stmt), type2_out, rhs2_out))
2028 if (*type1_out == NULL)
2030 if (*type2_out == NULL || !int_fits_type_p (*rhs1_out, *type2_out))
2032 *type1_out = *type2_out;
2035 if (*type2_out == NULL)
2037 if (!int_fits_type_p (*rhs2_out, *type1_out))
2039 *type2_out = *type1_out;
2045 /* Process a single gimple statement STMT, which has a MULT_EXPR as
2046 its rhs, and try to convert it into a WIDEN_MULT_EXPR. The return
2047 value is true iff we converted the statement. */
2050 convert_mult_to_widen (gimple stmt)
2052 tree lhs, rhs1, rhs2, type, type1, type2;
2053 enum insn_code handler;
2055 lhs = gimple_assign_lhs (stmt);
2056 type = TREE_TYPE (lhs);
2057 if (TREE_CODE (type) != INTEGER_TYPE)
2060 if (!is_widening_mult_p (stmt, &type1, &rhs1, &type2, &rhs2))
2063 if (TYPE_UNSIGNED (type1) && TYPE_UNSIGNED (type2))
2064 handler = optab_handler (umul_widen_optab, TYPE_MODE (type));
2065 else if (!TYPE_UNSIGNED (type1) && !TYPE_UNSIGNED (type2))
2066 handler = optab_handler (smul_widen_optab, TYPE_MODE (type));
2068 handler = optab_handler (usmul_widen_optab, TYPE_MODE (type));
2070 if (handler == CODE_FOR_nothing)
2073 gimple_assign_set_rhs1 (stmt, fold_convert (type1, rhs1));
2074 gimple_assign_set_rhs2 (stmt, fold_convert (type2, rhs2));
2075 gimple_assign_set_rhs_code (stmt, WIDEN_MULT_EXPR);
2077 widen_mul_stats.widen_mults_inserted++;
2081 /* Process a single gimple statement STMT, which is found at the
2082 iterator GSI and has a either a PLUS_EXPR or a MINUS_EXPR as its
2083 rhs (given by CODE), and try to convert it into a
2084 WIDEN_MULT_PLUS_EXPR or a WIDEN_MULT_MINUS_EXPR. The return value
2085 is true iff we converted the statement. */
2088 convert_plusminus_to_widen (gimple_stmt_iterator *gsi, gimple stmt,
2089 enum tree_code code)
2091 gimple rhs1_stmt = NULL, rhs2_stmt = NULL;
2092 tree type, type1, type2;
2093 tree lhs, rhs1, rhs2, mult_rhs1, mult_rhs2, add_rhs;
2094 enum tree_code rhs1_code = ERROR_MARK, rhs2_code = ERROR_MARK;
2096 enum tree_code wmult_code;
2098 lhs = gimple_assign_lhs (stmt);
2099 type = TREE_TYPE (lhs);
2100 if (TREE_CODE (type) != INTEGER_TYPE
2101 && TREE_CODE (type) != FIXED_POINT_TYPE)
2104 if (code == MINUS_EXPR)
2105 wmult_code = WIDEN_MULT_MINUS_EXPR;
2107 wmult_code = WIDEN_MULT_PLUS_EXPR;
2109 rhs1 = gimple_assign_rhs1 (stmt);
2110 rhs2 = gimple_assign_rhs2 (stmt);
2112 if (TREE_CODE (rhs1) == SSA_NAME)
2114 rhs1_stmt = SSA_NAME_DEF_STMT (rhs1);
2115 if (is_gimple_assign (rhs1_stmt))
2116 rhs1_code = gimple_assign_rhs_code (rhs1_stmt);
2121 if (TREE_CODE (rhs2) == SSA_NAME)
2123 rhs2_stmt = SSA_NAME_DEF_STMT (rhs2);
2124 if (is_gimple_assign (rhs2_stmt))
2125 rhs2_code = gimple_assign_rhs_code (rhs2_stmt);
2130 if (code == PLUS_EXPR && rhs1_code == MULT_EXPR)
2132 if (!is_widening_mult_p (rhs1_stmt, &type1, &mult_rhs1,
2133 &type2, &mult_rhs2))
2137 else if (rhs2_code == MULT_EXPR)
2139 if (!is_widening_mult_p (rhs2_stmt, &type1, &mult_rhs1,
2140 &type2, &mult_rhs2))
2144 else if (code == PLUS_EXPR && rhs1_code == WIDEN_MULT_EXPR)
2146 mult_rhs1 = gimple_assign_rhs1 (rhs1_stmt);
2147 mult_rhs2 = gimple_assign_rhs2 (rhs1_stmt);
2148 type1 = TREE_TYPE (mult_rhs1);
2149 type2 = TREE_TYPE (mult_rhs2);
2152 else if (rhs2_code == WIDEN_MULT_EXPR)
2154 mult_rhs1 = gimple_assign_rhs1 (rhs2_stmt);
2155 mult_rhs2 = gimple_assign_rhs2 (rhs2_stmt);
2156 type1 = TREE_TYPE (mult_rhs1);
2157 type2 = TREE_TYPE (mult_rhs2);
2163 if (TYPE_UNSIGNED (type1) != TYPE_UNSIGNED (type2))
2166 /* Verify that the machine can perform a widening multiply
2167 accumulate in this mode/signedness combination, otherwise
2168 this transformation is likely to pessimize code. */
2169 this_optab = optab_for_tree_code (wmult_code, type1, optab_default);
2170 if (optab_handler (this_optab, TYPE_MODE (type)) == CODE_FOR_nothing)
2173 /* ??? May need some type verification here? */
2175 gimple_assign_set_rhs_with_ops_1 (gsi, wmult_code,
2176 fold_convert (type1, mult_rhs1),
2177 fold_convert (type2, mult_rhs2),
2179 update_stmt (gsi_stmt (*gsi));
2180 widen_mul_stats.maccs_inserted++;
2184 /* Combine the multiplication at MUL_STMT with operands MULOP1 and MULOP2
2185 with uses in additions and subtractions to form fused multiply-add
2186 operations. Returns true if successful and MUL_STMT should be removed. */
2189 convert_mult_to_fma (gimple mul_stmt, tree op1, tree op2)
2191 tree mul_result = gimple_get_lhs (mul_stmt);
2192 tree type = TREE_TYPE (mul_result);
2193 gimple use_stmt, neguse_stmt, fma_stmt;
2194 use_operand_p use_p;
2195 imm_use_iterator imm_iter;
2197 if (FLOAT_TYPE_P (type)
2198 && flag_fp_contract_mode == FP_CONTRACT_OFF)
2201 /* We don't want to do bitfield reduction ops. */
2202 if (INTEGRAL_TYPE_P (type)
2203 && (TYPE_PRECISION (type)
2204 != GET_MODE_PRECISION (TYPE_MODE (type))))
2207 /* If the target doesn't support it, don't generate it. We assume that
2208 if fma isn't available then fms, fnma or fnms are not either. */
2209 if (optab_handler (fma_optab, TYPE_MODE (type)) == CODE_FOR_nothing)
2212 /* Make sure that the multiplication statement becomes dead after
2213 the transformation, thus that all uses are transformed to FMAs.
2214 This means we assume that an FMA operation has the same cost
2216 FOR_EACH_IMM_USE_FAST (use_p, imm_iter, mul_result)
2218 enum tree_code use_code;
2219 tree result = mul_result;
2220 bool negate_p = false;
2222 use_stmt = USE_STMT (use_p);
2224 if (is_gimple_debug (use_stmt))
2227 /* For now restrict this operations to single basic blocks. In theory
2228 we would want to support sinking the multiplication in
2234 to form a fma in the then block and sink the multiplication to the
2236 if (gimple_bb (use_stmt) != gimple_bb (mul_stmt))
2239 if (!is_gimple_assign (use_stmt))
2242 use_code = gimple_assign_rhs_code (use_stmt);
2244 /* A negate on the multiplication leads to FNMA. */
2245 if (use_code == NEGATE_EXPR)
2250 result = gimple_assign_lhs (use_stmt);
2252 /* Make sure the negate statement becomes dead with this
2253 single transformation. */
2254 if (!single_imm_use (gimple_assign_lhs (use_stmt),
2255 &use_p, &neguse_stmt))
2258 /* Make sure the multiplication isn't also used on that stmt. */
2259 FOR_EACH_PHI_OR_STMT_USE (usep, neguse_stmt, iter, SSA_OP_USE)
2260 if (USE_FROM_PTR (usep) == mul_result)
2264 use_stmt = neguse_stmt;
2265 if (gimple_bb (use_stmt) != gimple_bb (mul_stmt))
2267 if (!is_gimple_assign (use_stmt))
2270 use_code = gimple_assign_rhs_code (use_stmt);
2277 if (gimple_assign_rhs2 (use_stmt) == result)
2278 negate_p = !negate_p;
2283 /* FMA can only be formed from PLUS and MINUS. */
2287 /* We can't handle a * b + a * b. */
2288 if (gimple_assign_rhs1 (use_stmt) == gimple_assign_rhs2 (use_stmt))
2291 /* While it is possible to validate whether or not the exact form
2292 that we've recognized is available in the backend, the assumption
2293 is that the transformation is never a loss. For instance, suppose
2294 the target only has the plain FMA pattern available. Consider
2295 a*b-c -> fma(a,b,-c): we've exchanged MUL+SUB for FMA+NEG, which
2296 is still two operations. Consider -(a*b)-c -> fma(-a,b,-c): we
2297 still have 3 operations, but in the FMA form the two NEGs are
2298 independant and could be run in parallel. */
2301 FOR_EACH_IMM_USE_STMT (use_stmt, imm_iter, mul_result)
2303 gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt);
2304 enum tree_code use_code;
2305 tree addop, mulop1 = op1, result = mul_result;
2306 bool negate_p = false;
2308 if (is_gimple_debug (use_stmt))
2311 use_code = gimple_assign_rhs_code (use_stmt);
2312 if (use_code == NEGATE_EXPR)
2314 result = gimple_assign_lhs (use_stmt);
2315 single_imm_use (gimple_assign_lhs (use_stmt), &use_p, &neguse_stmt);
2316 gsi_remove (&gsi, true);
2317 release_defs (use_stmt);
2319 use_stmt = neguse_stmt;
2320 gsi = gsi_for_stmt (use_stmt);
2321 use_code = gimple_assign_rhs_code (use_stmt);
2325 if (gimple_assign_rhs1 (use_stmt) == result)
2327 addop = gimple_assign_rhs2 (use_stmt);
2328 /* a * b - c -> a * b + (-c) */
2329 if (gimple_assign_rhs_code (use_stmt) == MINUS_EXPR)
2330 addop = force_gimple_operand_gsi (&gsi,
2331 build1 (NEGATE_EXPR,
2333 true, NULL_TREE, true,
2338 addop = gimple_assign_rhs1 (use_stmt);
2339 /* a - b * c -> (-b) * c + a */
2340 if (gimple_assign_rhs_code (use_stmt) == MINUS_EXPR)
2341 negate_p = !negate_p;
2345 mulop1 = force_gimple_operand_gsi (&gsi,
2346 build1 (NEGATE_EXPR,
2348 true, NULL_TREE, true,
2351 fma_stmt = gimple_build_assign_with_ops3 (FMA_EXPR,
2352 gimple_assign_lhs (use_stmt),
2355 gsi_replace (&gsi, fma_stmt, true);
2356 widen_mul_stats.fmas_inserted++;
2362 /* Find integer multiplications where the operands are extended from
2363 smaller types, and replace the MULT_EXPR with a WIDEN_MULT_EXPR
2364 where appropriate. */
2367 execute_optimize_widening_mul (void)
2370 bool cfg_changed = false;
2372 memset (&widen_mul_stats, 0, sizeof (widen_mul_stats));
2376 gimple_stmt_iterator gsi;
2378 for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi);)
2380 gimple stmt = gsi_stmt (gsi);
2381 enum tree_code code;
2383 if (is_gimple_assign (stmt))
2385 code = gimple_assign_rhs_code (stmt);
2389 if (!convert_mult_to_widen (stmt)
2390 && convert_mult_to_fma (stmt,
2391 gimple_assign_rhs1 (stmt),
2392 gimple_assign_rhs2 (stmt)))
2394 gsi_remove (&gsi, true);
2395 release_defs (stmt);
2402 convert_plusminus_to_widen (&gsi, stmt, code);
2408 else if (is_gimple_call (stmt)
2409 && gimple_call_lhs (stmt))
2411 tree fndecl = gimple_call_fndecl (stmt);
2413 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
2415 switch (DECL_FUNCTION_CODE (fndecl))
2420 if (TREE_CODE (gimple_call_arg (stmt, 1)) == REAL_CST
2421 && REAL_VALUES_EQUAL
2422 (TREE_REAL_CST (gimple_call_arg (stmt, 1)),
2424 && convert_mult_to_fma (stmt,
2425 gimple_call_arg (stmt, 0),
2426 gimple_call_arg (stmt, 0)))
2428 unlink_stmt_vdef (stmt);
2429 gsi_remove (&gsi, true);
2430 release_defs (stmt);
2431 if (gimple_purge_dead_eh_edges (bb))
2445 statistics_counter_event (cfun, "widening multiplications inserted",
2446 widen_mul_stats.widen_mults_inserted);
2447 statistics_counter_event (cfun, "widening maccs inserted",
2448 widen_mul_stats.maccs_inserted);
2449 statistics_counter_event (cfun, "fused multiply-adds inserted",
2450 widen_mul_stats.fmas_inserted);
2452 return cfg_changed ? TODO_cleanup_cfg : 0;
2456 gate_optimize_widening_mul (void)
2458 return flag_expensive_optimizations && optimize;
2461 struct gimple_opt_pass pass_optimize_widening_mul =
2465 "widening_mul", /* name */
2466 gate_optimize_widening_mul, /* gate */
2467 execute_optimize_widening_mul, /* execute */
2470 0, /* static_pass_number */
2471 TV_NONE, /* tv_id */
2472 PROP_ssa, /* properties_required */
2473 0, /* properties_provided */
2474 0, /* properties_destroyed */
2475 0, /* todo_flags_start */
2478 | TODO_update_ssa /* todo_flags_finish */