2 Copyright (C) 2003-2013 Free Software Foundation, Inc.
3 Contributed by Dorit Naishlos <dorit@il.ibm.com> and
4 Ira Rosen <irar@il.ibm.com>
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
24 #include "coretypes.h"
29 #include "basic-block.h"
30 #include "gimple-pretty-print.h"
31 #include "tree-flow.h"
32 #include "tree-pass.h"
38 #include "diagnostic-core.h"
39 #include "tree-chrec.h"
40 #include "tree-scalar-evolution.h"
41 #include "tree-vectorizer.h"
44 /* Loop Vectorization Pass.
46 This pass tries to vectorize loops.
48 For example, the vectorizer transforms the following simple loop:
50 short a[N]; short b[N]; short c[N]; int i;
56 as if it was manually vectorized by rewriting the source code into:
58 typedef int __attribute__((mode(V8HI))) v8hi;
59 short a[N]; short b[N]; short c[N]; int i;
60 v8hi *pa = (v8hi*)a, *pb = (v8hi*)b, *pc = (v8hi*)c;
63 for (i=0; i<N/8; i++){
70 The main entry to this pass is vectorize_loops(), in which
71 the vectorizer applies a set of analyses on a given set of loops,
72 followed by the actual vectorization transformation for the loops that
73 had successfully passed the analysis phase.
74 Throughout this pass we make a distinction between two types of
75 data: scalars (which are represented by SSA_NAMES), and memory references
76 ("data-refs"). These two types of data require different handling both
77 during analysis and transformation. The types of data-refs that the
78 vectorizer currently supports are ARRAY_REFS which base is an array DECL
79 (not a pointer), and INDIRECT_REFS through pointers; both array and pointer
80 accesses are required to have a simple (consecutive) access pattern.
84 The driver for the analysis phase is vect_analyze_loop().
85 It applies a set of analyses, some of which rely on the scalar evolution
86 analyzer (scev) developed by Sebastian Pop.
88 During the analysis phase the vectorizer records some information
89 per stmt in a "stmt_vec_info" struct which is attached to each stmt in the
90 loop, as well as general information about the loop as a whole, which is
91 recorded in a "loop_vec_info" struct attached to each loop.
95 The loop transformation phase scans all the stmts in the loop, and
96 creates a vector stmt (or a sequence of stmts) for each scalar stmt S in
97 the loop that needs to be vectorized. It inserts the vector code sequence
98 just before the scalar stmt S, and records a pointer to the vector code
99 in STMT_VINFO_VEC_STMT (stmt_info) (stmt_info is the stmt_vec_info struct
100 attached to S). This pointer will be used for the vectorization of following
101 stmts which use the def of stmt S. Stmt S is removed if it writes to memory;
102 otherwise, we rely on dead code elimination for removing it.
104 For example, say stmt S1 was vectorized into stmt VS1:
107 S1: b = x[i]; STMT_VINFO_VEC_STMT (stmt_info (S1)) = VS1
110 To vectorize stmt S2, the vectorizer first finds the stmt that defines
111 the operand 'b' (S1), and gets the relevant vector def 'vb' from the
112 vector stmt VS1 pointed to by STMT_VINFO_VEC_STMT (stmt_info (S1)). The
113 resulting sequence would be:
116 S1: b = x[i]; STMT_VINFO_VEC_STMT (stmt_info (S1)) = VS1
118 S2: a = b; STMT_VINFO_VEC_STMT (stmt_info (S2)) = VS2
120 Operands that are not SSA_NAMEs, are data-refs that appear in
121 load/store operations (like 'x[i]' in S1), and are handled differently.
125 Currently the only target specific information that is used is the
126 size of the vector (in bytes) - "TARGET_VECTORIZE_UNITS_PER_SIMD_WORD".
127 Targets that can support different sizes of vectors, for now will need
128 to specify one value for "TARGET_VECTORIZE_UNITS_PER_SIMD_WORD". More
129 flexibility will be added in the future.
131 Since we only vectorize operations which vector form can be
132 expressed using existing tree codes, to verify that an operation is
133 supported, the vectorizer checks the relevant optab at the relevant
134 machine_mode (e.g, optab_handler (add_optab, V8HImode)). If
135 the value found is CODE_FOR_nothing, then there's no target support, and
136 we can't vectorize the stmt.
138 For additional information on this project see:
139 http://gcc.gnu.org/projects/tree-ssa/vectorization.html
142 static void vect_estimate_min_profitable_iters (loop_vec_info
, int *, int *);
144 /* Function vect_determine_vectorization_factor
146 Determine the vectorization factor (VF). VF is the number of data elements
147 that are operated upon in parallel in a single iteration of the vectorized
148 loop. For example, when vectorizing a loop that operates on 4byte elements,
149 on a target with vector size (VS) 16byte, the VF is set to 4, since 4
150 elements can fit in a single vector register.
152 We currently support vectorization of loops in which all types operated upon
153 are of the same size. Therefore this function currently sets VF according to
154 the size of the types operated upon, and fails if there are multiple sizes
157 VF is also the factor by which the loop iterations are strip-mined, e.g.:
164 for (i=0; i<N; i+=VF){
165 a[i:VF] = b[i:VF] + c[i:VF];
170 vect_determine_vectorization_factor (loop_vec_info loop_vinfo
)
172 struct loop
*loop
= LOOP_VINFO_LOOP (loop_vinfo
);
173 basic_block
*bbs
= LOOP_VINFO_BBS (loop_vinfo
);
174 int nbbs
= loop
->num_nodes
;
175 gimple_stmt_iterator si
;
176 unsigned int vectorization_factor
= 0;
181 stmt_vec_info stmt_info
;
184 gimple stmt
, pattern_stmt
= NULL
;
185 gimple_seq pattern_def_seq
= NULL
;
186 gimple_stmt_iterator pattern_def_si
= gsi_none ();
187 bool analyze_pattern_stmt
= false;
189 if (dump_enabled_p ())
190 dump_printf_loc (MSG_NOTE
, vect_location
,
191 "=== vect_determine_vectorization_factor ===");
193 for (i
= 0; i
< nbbs
; i
++)
195 basic_block bb
= bbs
[i
];
197 for (si
= gsi_start_phis (bb
); !gsi_end_p (si
); gsi_next (&si
))
200 stmt_info
= vinfo_for_stmt (phi
);
201 if (dump_enabled_p ())
203 dump_printf_loc (MSG_NOTE
, vect_location
, "==> examining phi: ");
204 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, phi
, 0);
207 gcc_assert (stmt_info
);
209 if (STMT_VINFO_RELEVANT_P (stmt_info
))
211 gcc_assert (!STMT_VINFO_VECTYPE (stmt_info
));
212 scalar_type
= TREE_TYPE (PHI_RESULT (phi
));
214 if (dump_enabled_p ())
216 dump_printf_loc (MSG_NOTE
, vect_location
,
217 "get vectype for scalar type: ");
218 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, scalar_type
);
221 vectype
= get_vectype_for_scalar_type (scalar_type
);
224 if (dump_enabled_p ())
226 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
227 "not vectorized: unsupported "
229 dump_generic_expr (MSG_MISSED_OPTIMIZATION
, TDF_SLIM
,
234 STMT_VINFO_VECTYPE (stmt_info
) = vectype
;
236 if (dump_enabled_p ())
238 dump_printf_loc (MSG_NOTE
, vect_location
, "vectype: ");
239 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, vectype
);
242 nunits
= TYPE_VECTOR_SUBPARTS (vectype
);
243 if (dump_enabled_p ())
244 dump_printf_loc (MSG_NOTE
, vect_location
, "nunits = %d", nunits
);
246 if (!vectorization_factor
247 || (nunits
> vectorization_factor
))
248 vectorization_factor
= nunits
;
252 for (si
= gsi_start_bb (bb
); !gsi_end_p (si
) || analyze_pattern_stmt
;)
256 if (analyze_pattern_stmt
)
259 stmt
= gsi_stmt (si
);
261 stmt_info
= vinfo_for_stmt (stmt
);
263 if (dump_enabled_p ())
265 dump_printf_loc (MSG_NOTE
, vect_location
,
266 "==> examining statement: ");
267 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, stmt
, 0);
270 gcc_assert (stmt_info
);
272 /* Skip stmts which do not need to be vectorized. */
273 if (!STMT_VINFO_RELEVANT_P (stmt_info
)
274 && !STMT_VINFO_LIVE_P (stmt_info
))
276 if (STMT_VINFO_IN_PATTERN_P (stmt_info
)
277 && (pattern_stmt
= STMT_VINFO_RELATED_STMT (stmt_info
))
278 && (STMT_VINFO_RELEVANT_P (vinfo_for_stmt (pattern_stmt
))
279 || STMT_VINFO_LIVE_P (vinfo_for_stmt (pattern_stmt
))))
282 stmt_info
= vinfo_for_stmt (pattern_stmt
);
283 if (dump_enabled_p ())
285 dump_printf_loc (MSG_NOTE
, vect_location
,
286 "==> examining pattern statement: ");
287 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, stmt
, 0);
292 if (dump_enabled_p ())
293 dump_printf_loc (MSG_NOTE
, vect_location
, "skip.");
298 else if (STMT_VINFO_IN_PATTERN_P (stmt_info
)
299 && (pattern_stmt
= STMT_VINFO_RELATED_STMT (stmt_info
))
300 && (STMT_VINFO_RELEVANT_P (vinfo_for_stmt (pattern_stmt
))
301 || STMT_VINFO_LIVE_P (vinfo_for_stmt (pattern_stmt
))))
302 analyze_pattern_stmt
= true;
304 /* If a pattern statement has def stmts, analyze them too. */
305 if (is_pattern_stmt_p (stmt_info
))
307 if (pattern_def_seq
== NULL
)
309 pattern_def_seq
= STMT_VINFO_PATTERN_DEF_SEQ (stmt_info
);
310 pattern_def_si
= gsi_start (pattern_def_seq
);
312 else if (!gsi_end_p (pattern_def_si
))
313 gsi_next (&pattern_def_si
);
314 if (pattern_def_seq
!= NULL
)
316 gimple pattern_def_stmt
= NULL
;
317 stmt_vec_info pattern_def_stmt_info
= NULL
;
319 while (!gsi_end_p (pattern_def_si
))
321 pattern_def_stmt
= gsi_stmt (pattern_def_si
);
322 pattern_def_stmt_info
323 = vinfo_for_stmt (pattern_def_stmt
);
324 if (STMT_VINFO_RELEVANT_P (pattern_def_stmt_info
)
325 || STMT_VINFO_LIVE_P (pattern_def_stmt_info
))
327 gsi_next (&pattern_def_si
);
330 if (!gsi_end_p (pattern_def_si
))
332 if (dump_enabled_p ())
334 dump_printf_loc (MSG_NOTE
, vect_location
,
335 "==> examining pattern def stmt: ");
336 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
,
337 pattern_def_stmt
, 0);
340 stmt
= pattern_def_stmt
;
341 stmt_info
= pattern_def_stmt_info
;
345 pattern_def_si
= gsi_none ();
346 analyze_pattern_stmt
= false;
350 analyze_pattern_stmt
= false;
353 if (gimple_get_lhs (stmt
) == NULL_TREE
)
355 if (dump_enabled_p ())
357 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
358 "not vectorized: irregular stmt.");
359 dump_gimple_stmt (MSG_MISSED_OPTIMIZATION
, TDF_SLIM
, stmt
,
365 if (VECTOR_MODE_P (TYPE_MODE (gimple_expr_type (stmt
))))
367 if (dump_enabled_p ())
369 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
370 "not vectorized: vector stmt in loop:");
371 dump_gimple_stmt (MSG_MISSED_OPTIMIZATION
, TDF_SLIM
, stmt
, 0);
376 if (STMT_VINFO_VECTYPE (stmt_info
))
378 /* The only case when a vectype had been already set is for stmts
379 that contain a dataref, or for "pattern-stmts" (stmts
380 generated by the vectorizer to represent/replace a certain
382 gcc_assert (STMT_VINFO_DATA_REF (stmt_info
)
383 || is_pattern_stmt_p (stmt_info
)
384 || !gsi_end_p (pattern_def_si
));
385 vectype
= STMT_VINFO_VECTYPE (stmt_info
);
389 gcc_assert (!STMT_VINFO_DATA_REF (stmt_info
));
390 scalar_type
= TREE_TYPE (gimple_get_lhs (stmt
));
391 if (dump_enabled_p ())
393 dump_printf_loc (MSG_NOTE
, vect_location
,
394 "get vectype for scalar type: ");
395 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, scalar_type
);
397 vectype
= get_vectype_for_scalar_type (scalar_type
);
400 if (dump_enabled_p ())
402 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
403 "not vectorized: unsupported "
405 dump_generic_expr (MSG_MISSED_OPTIMIZATION
, TDF_SLIM
,
411 STMT_VINFO_VECTYPE (stmt_info
) = vectype
;
414 /* The vectorization factor is according to the smallest
415 scalar type (or the largest vector size, but we only
416 support one vector size per loop). */
417 scalar_type
= vect_get_smallest_scalar_type (stmt
, &dummy
,
419 if (dump_enabled_p ())
421 dump_printf_loc (MSG_NOTE
, vect_location
,
422 "get vectype for scalar type: ");
423 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, scalar_type
);
425 vf_vectype
= get_vectype_for_scalar_type (scalar_type
);
428 if (dump_enabled_p ())
430 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
431 "not vectorized: unsupported data-type ");
432 dump_generic_expr (MSG_MISSED_OPTIMIZATION
, TDF_SLIM
,
438 if ((GET_MODE_SIZE (TYPE_MODE (vectype
))
439 != GET_MODE_SIZE (TYPE_MODE (vf_vectype
))))
441 if (dump_enabled_p ())
443 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
444 "not vectorized: different sized vector "
445 "types in statement, ");
446 dump_generic_expr (MSG_MISSED_OPTIMIZATION
, TDF_SLIM
,
448 dump_printf (MSG_MISSED_OPTIMIZATION
, " and ");
449 dump_generic_expr (MSG_MISSED_OPTIMIZATION
, TDF_SLIM
,
455 if (dump_enabled_p ())
457 dump_printf_loc (MSG_NOTE
, vect_location
, "vectype: ");
458 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, vf_vectype
);
461 nunits
= TYPE_VECTOR_SUBPARTS (vf_vectype
);
462 if (dump_enabled_p ())
463 dump_printf_loc (MSG_NOTE
, vect_location
, "nunits = %d", nunits
);
464 if (!vectorization_factor
465 || (nunits
> vectorization_factor
))
466 vectorization_factor
= nunits
;
468 if (!analyze_pattern_stmt
&& gsi_end_p (pattern_def_si
))
470 pattern_def_seq
= NULL
;
476 /* TODO: Analyze cost. Decide if worth while to vectorize. */
477 if (dump_enabled_p ())
478 dump_printf_loc (MSG_NOTE
, vect_location
, "vectorization factor = %d",
479 vectorization_factor
);
480 if (vectorization_factor
<= 1)
482 if (dump_enabled_p ())
483 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
484 "not vectorized: unsupported data-type");
487 LOOP_VINFO_VECT_FACTOR (loop_vinfo
) = vectorization_factor
;
493 /* Function vect_is_simple_iv_evolution.
495 FORNOW: A simple evolution of an induction variables in the loop is
496 considered a polynomial evolution with constant step. */
499 vect_is_simple_iv_evolution (unsigned loop_nb
, tree access_fn
, tree
* init
,
504 tree evolution_part
= evolution_part_in_loop_num (access_fn
, loop_nb
);
506 /* When there is no evolution in this loop, the evolution function
508 if (evolution_part
== NULL_TREE
)
511 /* When the evolution is a polynomial of degree >= 2
512 the evolution function is not "simple". */
513 if (tree_is_chrec (evolution_part
))
516 step_expr
= evolution_part
;
517 init_expr
= unshare_expr (initial_condition_in_loop_num (access_fn
, loop_nb
));
519 if (dump_enabled_p ())
521 dump_printf_loc (MSG_NOTE
, vect_location
, "step: ");
522 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, step_expr
);
523 dump_printf (MSG_NOTE
, ", init: ");
524 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, init_expr
);
530 if (TREE_CODE (step_expr
) != INTEGER_CST
)
532 if (dump_enabled_p ())
533 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
541 /* Function vect_analyze_scalar_cycles_1.
543 Examine the cross iteration def-use cycles of scalar variables
544 in LOOP. LOOP_VINFO represents the loop that is now being
545 considered for vectorization (can be LOOP, or an outer-loop
549 vect_analyze_scalar_cycles_1 (loop_vec_info loop_vinfo
, struct loop
*loop
)
551 basic_block bb
= loop
->header
;
553 vec
<gimple
> worklist
;
554 worklist
.create (64);
555 gimple_stmt_iterator gsi
;
558 if (dump_enabled_p ())
559 dump_printf_loc (MSG_NOTE
, vect_location
,
560 "=== vect_analyze_scalar_cycles ===");
562 /* First - identify all inductions. Reduction detection assumes that all the
563 inductions have been identified, therefore, this order must not be
565 for (gsi
= gsi_start_phis (bb
); !gsi_end_p (gsi
); gsi_next (&gsi
))
567 gimple phi
= gsi_stmt (gsi
);
568 tree access_fn
= NULL
;
569 tree def
= PHI_RESULT (phi
);
570 stmt_vec_info stmt_vinfo
= vinfo_for_stmt (phi
);
572 if (dump_enabled_p ())
574 dump_printf_loc (MSG_NOTE
, vect_location
, "Analyze phi: ");
575 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, phi
, 0);
578 /* Skip virtual phi's. The data dependences that are associated with
579 virtual defs/uses (i.e., memory accesses) are analyzed elsewhere. */
580 if (virtual_operand_p (def
))
583 STMT_VINFO_DEF_TYPE (stmt_vinfo
) = vect_unknown_def_type
;
585 /* Analyze the evolution function. */
586 access_fn
= analyze_scalar_evolution (loop
, def
);
589 STRIP_NOPS (access_fn
);
590 if (dump_enabled_p ())
592 dump_printf_loc (MSG_NOTE
, vect_location
,
593 "Access function of PHI: ");
594 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, access_fn
);
596 STMT_VINFO_LOOP_PHI_EVOLUTION_PART (stmt_vinfo
)
597 = evolution_part_in_loop_num (access_fn
, loop
->num
);
601 || !vect_is_simple_iv_evolution (loop
->num
, access_fn
, &dumy
, &dumy
))
603 worklist
.safe_push (phi
);
607 gcc_assert (STMT_VINFO_LOOP_PHI_EVOLUTION_PART (stmt_vinfo
) != NULL_TREE
);
609 if (dump_enabled_p ())
610 dump_printf_loc (MSG_NOTE
, vect_location
, "Detected induction.");
611 STMT_VINFO_DEF_TYPE (stmt_vinfo
) = vect_induction_def
;
615 /* Second - identify all reductions and nested cycles. */
616 while (worklist
.length () > 0)
618 gimple phi
= worklist
.pop ();
619 tree def
= PHI_RESULT (phi
);
620 stmt_vec_info stmt_vinfo
= vinfo_for_stmt (phi
);
624 if (dump_enabled_p ())
626 dump_printf_loc (MSG_NOTE
, vect_location
, "Analyze phi: ");
627 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, phi
, 0);
630 gcc_assert (!virtual_operand_p (def
)
631 && STMT_VINFO_DEF_TYPE (stmt_vinfo
) == vect_unknown_def_type
);
633 nested_cycle
= (loop
!= LOOP_VINFO_LOOP (loop_vinfo
));
634 reduc_stmt
= vect_force_simple_reduction (loop_vinfo
, phi
, !nested_cycle
,
640 if (dump_enabled_p ())
641 dump_printf_loc (MSG_NOTE
, vect_location
,
642 "Detected double reduction.");
644 STMT_VINFO_DEF_TYPE (stmt_vinfo
) = vect_double_reduction_def
;
645 STMT_VINFO_DEF_TYPE (vinfo_for_stmt (reduc_stmt
)) =
646 vect_double_reduction_def
;
652 if (dump_enabled_p ())
653 dump_printf_loc (MSG_NOTE
, vect_location
,
654 "Detected vectorizable nested cycle.");
656 STMT_VINFO_DEF_TYPE (stmt_vinfo
) = vect_nested_cycle
;
657 STMT_VINFO_DEF_TYPE (vinfo_for_stmt (reduc_stmt
)) =
662 if (dump_enabled_p ())
663 dump_printf_loc (MSG_NOTE
, vect_location
,
664 "Detected reduction.");
666 STMT_VINFO_DEF_TYPE (stmt_vinfo
) = vect_reduction_def
;
667 STMT_VINFO_DEF_TYPE (vinfo_for_stmt (reduc_stmt
)) =
669 /* Store the reduction cycles for possible vectorization in
671 LOOP_VINFO_REDUCTIONS (loop_vinfo
).safe_push (reduc_stmt
);
676 if (dump_enabled_p ())
677 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
678 "Unknown def-use cycle pattern.");
685 /* Function vect_analyze_scalar_cycles.
687 Examine the cross iteration def-use cycles of scalar variables, by
688 analyzing the loop-header PHIs of scalar variables. Classify each
689 cycle as one of the following: invariant, induction, reduction, unknown.
690 We do that for the loop represented by LOOP_VINFO, and also to its
691 inner-loop, if exists.
692 Examples for scalar cycles:
707 vect_analyze_scalar_cycles (loop_vec_info loop_vinfo
)
709 struct loop
*loop
= LOOP_VINFO_LOOP (loop_vinfo
);
711 vect_analyze_scalar_cycles_1 (loop_vinfo
, loop
);
713 /* When vectorizing an outer-loop, the inner-loop is executed sequentially.
714 Reductions in such inner-loop therefore have different properties than
715 the reductions in the nest that gets vectorized:
716 1. When vectorized, they are executed in the same order as in the original
717 scalar loop, so we can't change the order of computation when
719 2. FIXME: Inner-loop reductions can be used in the inner-loop, so the
720 current checks are too strict. */
723 vect_analyze_scalar_cycles_1 (loop_vinfo
, loop
->inner
);
726 /* Function vect_get_loop_niters.
728 Determine how many iterations the loop is executed.
729 If an expression that represents the number of iterations
730 can be constructed, place it in NUMBER_OF_ITERATIONS.
731 Return the loop exit condition. */
734 vect_get_loop_niters (struct loop
*loop
, tree
*number_of_iterations
)
738 if (dump_enabled_p ())
739 dump_printf_loc (MSG_NOTE
, vect_location
,
740 "=== get_loop_niters ===");
741 niters
= number_of_exit_cond_executions (loop
);
743 if (niters
!= NULL_TREE
744 && niters
!= chrec_dont_know
)
746 *number_of_iterations
= niters
;
748 if (dump_enabled_p ())
750 dump_printf_loc (MSG_NOTE
, vect_location
, "==> get_loop_niters:");
751 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, *number_of_iterations
);
755 return get_loop_exit_condition (loop
);
759 /* Function bb_in_loop_p
761 Used as predicate for dfs order traversal of the loop bbs. */
764 bb_in_loop_p (const_basic_block bb
, const void *data
)
766 const struct loop
*const loop
= (const struct loop
*)data
;
767 if (flow_bb_inside_loop_p (loop
, bb
))
773 /* Function new_loop_vec_info.
775 Create and initialize a new loop_vec_info struct for LOOP, as well as
776 stmt_vec_info structs for all the stmts in LOOP. */
779 new_loop_vec_info (struct loop
*loop
)
783 gimple_stmt_iterator si
;
784 unsigned int i
, nbbs
;
786 res
= (loop_vec_info
) xcalloc (1, sizeof (struct _loop_vec_info
));
787 LOOP_VINFO_LOOP (res
) = loop
;
789 bbs
= get_loop_body (loop
);
791 /* Create/Update stmt_info for all stmts in the loop. */
792 for (i
= 0; i
< loop
->num_nodes
; i
++)
794 basic_block bb
= bbs
[i
];
796 /* BBs in a nested inner-loop will have been already processed (because
797 we will have called vect_analyze_loop_form for any nested inner-loop).
798 Therefore, for stmts in an inner-loop we just want to update the
799 STMT_VINFO_LOOP_VINFO field of their stmt_info to point to the new
800 loop_info of the outer-loop we are currently considering to vectorize
801 (instead of the loop_info of the inner-loop).
802 For stmts in other BBs we need to create a stmt_info from scratch. */
803 if (bb
->loop_father
!= loop
)
806 gcc_assert (loop
->inner
&& bb
->loop_father
== loop
->inner
);
807 for (si
= gsi_start_phis (bb
); !gsi_end_p (si
); gsi_next (&si
))
809 gimple phi
= gsi_stmt (si
);
810 stmt_vec_info stmt_info
= vinfo_for_stmt (phi
);
811 loop_vec_info inner_loop_vinfo
=
812 STMT_VINFO_LOOP_VINFO (stmt_info
);
813 gcc_assert (loop
->inner
== LOOP_VINFO_LOOP (inner_loop_vinfo
));
814 STMT_VINFO_LOOP_VINFO (stmt_info
) = res
;
816 for (si
= gsi_start_bb (bb
); !gsi_end_p (si
); gsi_next (&si
))
818 gimple stmt
= gsi_stmt (si
);
819 stmt_vec_info stmt_info
= vinfo_for_stmt (stmt
);
820 loop_vec_info inner_loop_vinfo
=
821 STMT_VINFO_LOOP_VINFO (stmt_info
);
822 gcc_assert (loop
->inner
== LOOP_VINFO_LOOP (inner_loop_vinfo
));
823 STMT_VINFO_LOOP_VINFO (stmt_info
) = res
;
828 /* bb in current nest. */
829 for (si
= gsi_start_phis (bb
); !gsi_end_p (si
); gsi_next (&si
))
831 gimple phi
= gsi_stmt (si
);
832 gimple_set_uid (phi
, 0);
833 set_vinfo_for_stmt (phi
, new_stmt_vec_info (phi
, res
, NULL
));
836 for (si
= gsi_start_bb (bb
); !gsi_end_p (si
); gsi_next (&si
))
838 gimple stmt
= gsi_stmt (si
);
839 gimple_set_uid (stmt
, 0);
840 set_vinfo_for_stmt (stmt
, new_stmt_vec_info (stmt
, res
, NULL
));
845 /* CHECKME: We want to visit all BBs before their successors (except for
846 latch blocks, for which this assertion wouldn't hold). In the simple
847 case of the loop forms we allow, a dfs order of the BBs would the same
848 as reversed postorder traversal, so we are safe. */
851 bbs
= XCNEWVEC (basic_block
, loop
->num_nodes
);
852 nbbs
= dfs_enumerate_from (loop
->header
, 0, bb_in_loop_p
,
853 bbs
, loop
->num_nodes
, loop
);
854 gcc_assert (nbbs
== loop
->num_nodes
);
856 LOOP_VINFO_BBS (res
) = bbs
;
857 LOOP_VINFO_NITERS (res
) = NULL
;
858 LOOP_VINFO_NITERS_UNCHANGED (res
) = NULL
;
859 LOOP_VINFO_COST_MODEL_MIN_ITERS (res
) = 0;
860 LOOP_VINFO_VECTORIZABLE_P (res
) = 0;
861 LOOP_PEELING_FOR_ALIGNMENT (res
) = 0;
862 LOOP_VINFO_VECT_FACTOR (res
) = 0;
863 LOOP_VINFO_LOOP_NEST (res
).create (3);
864 LOOP_VINFO_DATAREFS (res
).create (10);
865 LOOP_VINFO_DDRS (res
).create (10 * 10);
866 LOOP_VINFO_UNALIGNED_DR (res
) = NULL
;
867 LOOP_VINFO_MAY_MISALIGN_STMTS (res
).create (
868 PARAM_VALUE (PARAM_VECT_MAX_VERSION_FOR_ALIGNMENT_CHECKS
));
869 LOOP_VINFO_MAY_ALIAS_DDRS (res
).create (
870 PARAM_VALUE (PARAM_VECT_MAX_VERSION_FOR_ALIAS_CHECKS
));
871 LOOP_VINFO_GROUPED_STORES (res
).create (10);
872 LOOP_VINFO_REDUCTIONS (res
).create (10);
873 LOOP_VINFO_REDUCTION_CHAINS (res
).create (10);
874 LOOP_VINFO_SLP_INSTANCES (res
).create (10);
875 LOOP_VINFO_SLP_UNROLLING_FACTOR (res
) = 1;
876 LOOP_VINFO_PEELING_HTAB (res
) = NULL
;
877 LOOP_VINFO_TARGET_COST_DATA (res
) = init_cost (loop
);
878 LOOP_VINFO_PEELING_FOR_GAPS (res
) = false;
879 LOOP_VINFO_OPERANDS_SWAPPED (res
) = false;
885 /* Function destroy_loop_vec_info.
887 Free LOOP_VINFO struct, as well as all the stmt_vec_info structs of all the
888 stmts in the loop. */
891 destroy_loop_vec_info (loop_vec_info loop_vinfo
, bool clean_stmts
)
896 gimple_stmt_iterator si
;
898 vec
<slp_instance
> slp_instances
;
899 slp_instance instance
;
905 loop
= LOOP_VINFO_LOOP (loop_vinfo
);
907 bbs
= LOOP_VINFO_BBS (loop_vinfo
);
908 nbbs
= clean_stmts
? loop
->num_nodes
: 0;
909 swapped
= LOOP_VINFO_OPERANDS_SWAPPED (loop_vinfo
);
911 for (j
= 0; j
< nbbs
; j
++)
913 basic_block bb
= bbs
[j
];
914 for (si
= gsi_start_phis (bb
); !gsi_end_p (si
); gsi_next (&si
))
915 free_stmt_vec_info (gsi_stmt (si
));
917 for (si
= gsi_start_bb (bb
); !gsi_end_p (si
); )
919 gimple stmt
= gsi_stmt (si
);
921 /* We may have broken canonical form by moving a constant
922 into RHS1 of a commutative op. Fix such occurrences. */
923 if (swapped
&& is_gimple_assign (stmt
))
925 enum tree_code code
= gimple_assign_rhs_code (stmt
);
927 if ((code
== PLUS_EXPR
928 || code
== POINTER_PLUS_EXPR
929 || code
== MULT_EXPR
)
930 && CONSTANT_CLASS_P (gimple_assign_rhs1 (stmt
)))
931 swap_tree_operands (stmt
,
932 gimple_assign_rhs1_ptr (stmt
),
933 gimple_assign_rhs2_ptr (stmt
));
936 /* Free stmt_vec_info. */
937 free_stmt_vec_info (stmt
);
942 free (LOOP_VINFO_BBS (loop_vinfo
));
943 free_data_refs (LOOP_VINFO_DATAREFS (loop_vinfo
));
944 free_dependence_relations (LOOP_VINFO_DDRS (loop_vinfo
));
945 LOOP_VINFO_LOOP_NEST (loop_vinfo
).release ();
946 LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo
).release ();
947 LOOP_VINFO_MAY_ALIAS_DDRS (loop_vinfo
).release ();
948 slp_instances
= LOOP_VINFO_SLP_INSTANCES (loop_vinfo
);
949 FOR_EACH_VEC_ELT (slp_instances
, j
, instance
)
950 vect_free_slp_instance (instance
);
952 LOOP_VINFO_SLP_INSTANCES (loop_vinfo
).release ();
953 LOOP_VINFO_GROUPED_STORES (loop_vinfo
).release ();
954 LOOP_VINFO_REDUCTIONS (loop_vinfo
).release ();
955 LOOP_VINFO_REDUCTION_CHAINS (loop_vinfo
).release ();
957 if (LOOP_VINFO_PEELING_HTAB (loop_vinfo
))
958 htab_delete (LOOP_VINFO_PEELING_HTAB (loop_vinfo
));
960 destroy_cost_data (LOOP_VINFO_TARGET_COST_DATA (loop_vinfo
));
967 /* Function vect_analyze_loop_1.
969 Apply a set of analyses on LOOP, and create a loop_vec_info struct
970 for it. The different analyses will record information in the
971 loop_vec_info struct. This is a subset of the analyses applied in
972 vect_analyze_loop, to be applied on an inner-loop nested in the loop
973 that is now considered for (outer-loop) vectorization. */
976 vect_analyze_loop_1 (struct loop
*loop
)
978 loop_vec_info loop_vinfo
;
980 if (dump_enabled_p ())
981 dump_printf_loc (MSG_NOTE
, vect_location
,
982 "===== analyze_loop_nest_1 =====");
984 /* Check the CFG characteristics of the loop (nesting, entry/exit, etc. */
986 loop_vinfo
= vect_analyze_loop_form (loop
);
989 if (dump_enabled_p ())
990 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
991 "bad inner-loop form.");
999 /* Function vect_analyze_loop_form.
1001 Verify that certain CFG restrictions hold, including:
1002 - the loop has a pre-header
1003 - the loop has a single entry and exit
1004 - the loop exit condition is simple enough, and the number of iterations
1005 can be analyzed (a countable loop). */
1008 vect_analyze_loop_form (struct loop
*loop
)
1010 loop_vec_info loop_vinfo
;
1012 tree number_of_iterations
= NULL
;
1013 loop_vec_info inner_loop_vinfo
= NULL
;
1015 if (dump_enabled_p ())
1016 dump_printf_loc (MSG_NOTE
, vect_location
,
1017 "=== vect_analyze_loop_form ===");
1019 /* Different restrictions apply when we are considering an inner-most loop,
1020 vs. an outer (nested) loop.
1021 (FORNOW. May want to relax some of these restrictions in the future). */
1025 /* Inner-most loop. We currently require that the number of BBs is
1026 exactly 2 (the header and latch). Vectorizable inner-most loops
1037 if (loop
->num_nodes
!= 2)
1039 if (dump_enabled_p ())
1040 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1041 "not vectorized: control flow in loop.");
1045 if (empty_block_p (loop
->header
))
1047 if (dump_enabled_p ())
1048 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1049 "not vectorized: empty loop.");
1055 struct loop
*innerloop
= loop
->inner
;
1058 /* Nested loop. We currently require that the loop is doubly-nested,
1059 contains a single inner loop, and the number of BBs is exactly 5.
1060 Vectorizable outer-loops look like this:
1072 The inner-loop has the properties expected of inner-most loops
1073 as described above. */
1075 if ((loop
->inner
)->inner
|| (loop
->inner
)->next
)
1077 if (dump_enabled_p ())
1078 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1079 "not vectorized: multiple nested loops.");
1083 /* Analyze the inner-loop. */
1084 inner_loop_vinfo
= vect_analyze_loop_1 (loop
->inner
);
1085 if (!inner_loop_vinfo
)
1087 if (dump_enabled_p ())
1088 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1089 "not vectorized: Bad inner loop.");
1093 if (!expr_invariant_in_loop_p (loop
,
1094 LOOP_VINFO_NITERS (inner_loop_vinfo
)))
1096 if (dump_enabled_p ())
1097 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1098 "not vectorized: inner-loop count not invariant.");
1099 destroy_loop_vec_info (inner_loop_vinfo
, true);
1103 if (loop
->num_nodes
!= 5)
1105 if (dump_enabled_p ())
1106 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1107 "not vectorized: control flow in loop.");
1108 destroy_loop_vec_info (inner_loop_vinfo
, true);
1112 gcc_assert (EDGE_COUNT (innerloop
->header
->preds
) == 2);
1113 entryedge
= EDGE_PRED (innerloop
->header
, 0);
1114 if (EDGE_PRED (innerloop
->header
, 0)->src
== innerloop
->latch
)
1115 entryedge
= EDGE_PRED (innerloop
->header
, 1);
1117 if (entryedge
->src
!= loop
->header
1118 || !single_exit (innerloop
)
1119 || single_exit (innerloop
)->dest
!= EDGE_PRED (loop
->latch
, 0)->src
)
1121 if (dump_enabled_p ())
1122 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1123 "not vectorized: unsupported outerloop form.");
1124 destroy_loop_vec_info (inner_loop_vinfo
, true);
1128 if (dump_enabled_p ())
1129 dump_printf_loc (MSG_NOTE
, vect_location
,
1130 "Considering outer-loop vectorization.");
1133 if (!single_exit (loop
)
1134 || EDGE_COUNT (loop
->header
->preds
) != 2)
1136 if (dump_enabled_p ())
1138 if (!single_exit (loop
))
1139 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1140 "not vectorized: multiple exits.");
1141 else if (EDGE_COUNT (loop
->header
->preds
) != 2)
1142 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1143 "not vectorized: too many incoming edges.");
1145 if (inner_loop_vinfo
)
1146 destroy_loop_vec_info (inner_loop_vinfo
, true);
1150 /* We assume that the loop exit condition is at the end of the loop. i.e,
1151 that the loop is represented as a do-while (with a proper if-guard
1152 before the loop if needed), where the loop header contains all the
1153 executable statements, and the latch is empty. */
1154 if (!empty_block_p (loop
->latch
)
1155 || !gimple_seq_empty_p (phi_nodes (loop
->latch
)))
1157 if (dump_enabled_p ())
1158 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1159 "not vectorized: latch block not empty.");
1160 if (inner_loop_vinfo
)
1161 destroy_loop_vec_info (inner_loop_vinfo
, true);
1165 /* Make sure there exists a single-predecessor exit bb: */
1166 if (!single_pred_p (single_exit (loop
)->dest
))
1168 edge e
= single_exit (loop
);
1169 if (!(e
->flags
& EDGE_ABNORMAL
))
1171 split_loop_exit_edge (e
);
1172 if (dump_enabled_p ())
1173 dump_printf (MSG_NOTE
, "split exit edge.");
1177 if (dump_enabled_p ())
1178 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1179 "not vectorized: abnormal loop exit edge.");
1180 if (inner_loop_vinfo
)
1181 destroy_loop_vec_info (inner_loop_vinfo
, true);
1186 loop_cond
= vect_get_loop_niters (loop
, &number_of_iterations
);
1189 if (dump_enabled_p ())
1190 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1191 "not vectorized: complicated exit condition.");
1192 if (inner_loop_vinfo
)
1193 destroy_loop_vec_info (inner_loop_vinfo
, true);
1197 if (!number_of_iterations
)
1199 if (dump_enabled_p ())
1200 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1201 "not vectorized: number of iterations cannot be "
1203 if (inner_loop_vinfo
)
1204 destroy_loop_vec_info (inner_loop_vinfo
, true);
1208 if (chrec_contains_undetermined (number_of_iterations
))
1210 if (dump_enabled_p ())
1211 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1212 "Infinite number of iterations.");
1213 if (inner_loop_vinfo
)
1214 destroy_loop_vec_info (inner_loop_vinfo
, true);
1218 if (!NITERS_KNOWN_P (number_of_iterations
))
1220 if (dump_enabled_p ())
1222 dump_printf_loc (MSG_NOTE
, vect_location
,
1223 "Symbolic number of iterations is ");
1224 dump_generic_expr (MSG_NOTE
, TDF_DETAILS
, number_of_iterations
);
1227 else if (TREE_INT_CST_LOW (number_of_iterations
) == 0)
1229 if (dump_enabled_p ())
1230 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1231 "not vectorized: number of iterations = 0.");
1232 if (inner_loop_vinfo
)
1233 destroy_loop_vec_info (inner_loop_vinfo
, true);
1237 loop_vinfo
= new_loop_vec_info (loop
);
1238 LOOP_VINFO_NITERS (loop_vinfo
) = number_of_iterations
;
1239 LOOP_VINFO_NITERS_UNCHANGED (loop_vinfo
) = number_of_iterations
;
1241 STMT_VINFO_TYPE (vinfo_for_stmt (loop_cond
)) = loop_exit_ctrl_vec_info_type
;
1243 /* CHECKME: May want to keep it around it in the future. */
1244 if (inner_loop_vinfo
)
1245 destroy_loop_vec_info (inner_loop_vinfo
, false);
1247 gcc_assert (!loop
->aux
);
1248 loop
->aux
= loop_vinfo
;
1253 /* Function vect_analyze_loop_operations.
1255 Scan the loop stmts and make sure they are all vectorizable. */
1258 vect_analyze_loop_operations (loop_vec_info loop_vinfo
, bool slp
)
1260 struct loop
*loop
= LOOP_VINFO_LOOP (loop_vinfo
);
1261 basic_block
*bbs
= LOOP_VINFO_BBS (loop_vinfo
);
1262 int nbbs
= loop
->num_nodes
;
1263 gimple_stmt_iterator si
;
1264 unsigned int vectorization_factor
= 0;
1267 stmt_vec_info stmt_info
;
1268 bool need_to_vectorize
= false;
1269 int min_profitable_iters
;
1270 int min_scalar_loop_bound
;
1272 bool only_slp_in_loop
= true, ok
;
1273 HOST_WIDE_INT max_niter
;
1274 HOST_WIDE_INT estimated_niter
;
1275 int min_profitable_estimate
;
1277 if (dump_enabled_p ())
1278 dump_printf_loc (MSG_NOTE
, vect_location
,
1279 "=== vect_analyze_loop_operations ===");
1281 gcc_assert (LOOP_VINFO_VECT_FACTOR (loop_vinfo
));
1282 vectorization_factor
= LOOP_VINFO_VECT_FACTOR (loop_vinfo
);
1285 /* If all the stmts in the loop can be SLPed, we perform only SLP, and
1286 vectorization factor of the loop is the unrolling factor required by
1287 the SLP instances. If that unrolling factor is 1, we say, that we
1288 perform pure SLP on loop - cross iteration parallelism is not
1290 for (i
= 0; i
< nbbs
; i
++)
1292 basic_block bb
= bbs
[i
];
1293 for (si
= gsi_start_bb (bb
); !gsi_end_p (si
); gsi_next (&si
))
1295 gimple stmt
= gsi_stmt (si
);
1296 stmt_vec_info stmt_info
= vinfo_for_stmt (stmt
);
1297 gcc_assert (stmt_info
);
1298 if ((STMT_VINFO_RELEVANT_P (stmt_info
)
1299 || VECTORIZABLE_CYCLE_DEF (STMT_VINFO_DEF_TYPE (stmt_info
)))
1300 && !PURE_SLP_STMT (stmt_info
))
1301 /* STMT needs both SLP and loop-based vectorization. */
1302 only_slp_in_loop
= false;
1306 if (only_slp_in_loop
)
1307 vectorization_factor
= LOOP_VINFO_SLP_UNROLLING_FACTOR (loop_vinfo
);
1309 vectorization_factor
= least_common_multiple (vectorization_factor
,
1310 LOOP_VINFO_SLP_UNROLLING_FACTOR (loop_vinfo
));
1312 LOOP_VINFO_VECT_FACTOR (loop_vinfo
) = vectorization_factor
;
1313 if (dump_enabled_p ())
1314 dump_printf_loc (MSG_NOTE
, vect_location
,
1315 "Updating vectorization factor to %d ",
1316 vectorization_factor
);
1319 for (i
= 0; i
< nbbs
; i
++)
1321 basic_block bb
= bbs
[i
];
1323 for (si
= gsi_start_phis (bb
); !gsi_end_p (si
); gsi_next (&si
))
1325 phi
= gsi_stmt (si
);
1328 stmt_info
= vinfo_for_stmt (phi
);
1329 if (dump_enabled_p ())
1331 dump_printf_loc (MSG_NOTE
, vect_location
, "examining phi: ");
1332 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, phi
, 0);
1335 /* Inner-loop loop-closed exit phi in outer-loop vectorization
1336 (i.e., a phi in the tail of the outer-loop). */
1337 if (! is_loop_header_bb_p (bb
))
1339 /* FORNOW: we currently don't support the case that these phis
1340 are not used in the outerloop (unless it is double reduction,
1341 i.e., this phi is vect_reduction_def), cause this case
1342 requires to actually do something here. */
1343 if ((!STMT_VINFO_RELEVANT_P (stmt_info
)
1344 || STMT_VINFO_LIVE_P (stmt_info
))
1345 && STMT_VINFO_DEF_TYPE (stmt_info
)
1346 != vect_double_reduction_def
)
1348 if (dump_enabled_p ())
1349 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1350 "Unsupported loop-closed phi in "
1355 /* If PHI is used in the outer loop, we check that its operand
1356 is defined in the inner loop. */
1357 if (STMT_VINFO_RELEVANT_P (stmt_info
))
1362 if (gimple_phi_num_args (phi
) != 1)
1365 phi_op
= PHI_ARG_DEF (phi
, 0);
1366 if (TREE_CODE (phi_op
) != SSA_NAME
)
1369 op_def_stmt
= SSA_NAME_DEF_STMT (phi_op
);
1371 || !flow_bb_inside_loop_p (loop
, gimple_bb (op_def_stmt
))
1372 || !vinfo_for_stmt (op_def_stmt
))
1375 if (STMT_VINFO_RELEVANT (vinfo_for_stmt (op_def_stmt
))
1376 != vect_used_in_outer
1377 && STMT_VINFO_RELEVANT (vinfo_for_stmt (op_def_stmt
))
1378 != vect_used_in_outer_by_reduction
)
1385 gcc_assert (stmt_info
);
1387 if (STMT_VINFO_LIVE_P (stmt_info
))
1389 /* FORNOW: not yet supported. */
1390 if (dump_enabled_p ())
1391 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1392 "not vectorized: value used after loop.");
1396 if (STMT_VINFO_RELEVANT (stmt_info
) == vect_used_in_scope
1397 && STMT_VINFO_DEF_TYPE (stmt_info
) != vect_induction_def
)
1399 /* A scalar-dependence cycle that we don't support. */
1400 if (dump_enabled_p ())
1401 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1402 "not vectorized: scalar dependence cycle.");
1406 if (STMT_VINFO_RELEVANT_P (stmt_info
))
1408 need_to_vectorize
= true;
1409 if (STMT_VINFO_DEF_TYPE (stmt_info
) == vect_induction_def
)
1410 ok
= vectorizable_induction (phi
, NULL
, NULL
);
1415 if (dump_enabled_p ())
1417 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1418 "not vectorized: relevant phi not "
1420 dump_gimple_stmt (MSG_MISSED_OPTIMIZATION
, TDF_SLIM
, phi
, 0);
1426 for (si
= gsi_start_bb (bb
); !gsi_end_p (si
); gsi_next (&si
))
1428 gimple stmt
= gsi_stmt (si
);
1429 if (!vect_analyze_stmt (stmt
, &need_to_vectorize
, NULL
))
1434 /* All operations in the loop are either irrelevant (deal with loop
1435 control, or dead), or only used outside the loop and can be moved
1436 out of the loop (e.g. invariants, inductions). The loop can be
1437 optimized away by scalar optimizations. We're better off not
1438 touching this loop. */
1439 if (!need_to_vectorize
)
1441 if (dump_enabled_p ())
1442 dump_printf_loc (MSG_NOTE
, vect_location
,
1443 "All the computation can be taken out of the loop.");
1444 if (dump_enabled_p ())
1445 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1446 "not vectorized: redundant loop. no profit to "
1451 if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo
) && dump_enabled_p ())
1452 dump_printf_loc (MSG_NOTE
, vect_location
,
1453 "vectorization_factor = %d, niters = "
1454 HOST_WIDE_INT_PRINT_DEC
, vectorization_factor
,
1455 LOOP_VINFO_INT_NITERS (loop_vinfo
));
1457 if ((LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo
)
1458 && (LOOP_VINFO_INT_NITERS (loop_vinfo
) < vectorization_factor
))
1459 || ((max_niter
= max_stmt_executions_int (loop
)) != -1
1460 && (unsigned HOST_WIDE_INT
) max_niter
< vectorization_factor
))
1462 if (dump_enabled_p ())
1463 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1464 "not vectorized: iteration count too small.");
1465 if (dump_enabled_p ())
1466 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1467 "not vectorized: iteration count smaller than "
1468 "vectorization factor.");
1472 /* Analyze cost. Decide if worth while to vectorize. */
1474 /* Once VF is set, SLP costs should be updated since the number of created
1475 vector stmts depends on VF. */
1476 vect_update_slp_costs_according_to_vf (loop_vinfo
);
1478 vect_estimate_min_profitable_iters (loop_vinfo
, &min_profitable_iters
,
1479 &min_profitable_estimate
);
1480 LOOP_VINFO_COST_MODEL_MIN_ITERS (loop_vinfo
) = min_profitable_iters
;
1482 if (min_profitable_iters
< 0)
1484 if (dump_enabled_p ())
1485 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1486 "not vectorized: vectorization not profitable.");
1487 if (dump_enabled_p ())
1488 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1489 "not vectorized: vector version will never be "
1494 min_scalar_loop_bound
= ((PARAM_VALUE (PARAM_MIN_VECT_LOOP_BOUND
)
1495 * vectorization_factor
) - 1);
1498 /* Use the cost model only if it is more conservative than user specified
1501 th
= (unsigned) min_scalar_loop_bound
;
1502 if (min_profitable_iters
1503 && (!min_scalar_loop_bound
1504 || min_profitable_iters
> min_scalar_loop_bound
))
1505 th
= (unsigned) min_profitable_iters
;
1507 if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo
)
1508 && LOOP_VINFO_INT_NITERS (loop_vinfo
) <= th
)
1510 if (dump_enabled_p ())
1511 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1512 "not vectorized: vectorization not profitable.");
1513 if (dump_enabled_p ())
1514 dump_printf_loc (MSG_NOTE
, vect_location
,
1515 "not vectorized: iteration count smaller than user "
1516 "specified loop bound parameter or minimum profitable "
1517 "iterations (whichever is more conservative).");
1521 if ((estimated_niter
= estimated_stmt_executions_int (loop
)) != -1
1522 && ((unsigned HOST_WIDE_INT
) estimated_niter
1523 <= MAX (th
, (unsigned)min_profitable_estimate
)))
1525 if (dump_enabled_p ())
1526 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1527 "not vectorized: estimated iteration count too "
1529 if (dump_enabled_p ())
1530 dump_printf_loc (MSG_NOTE
, vect_location
,
1531 "not vectorized: estimated iteration count smaller "
1532 "than specified loop bound parameter or minimum "
1533 "profitable iterations (whichever is more "
1538 if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo
)
1539 || LOOP_VINFO_INT_NITERS (loop_vinfo
) % vectorization_factor
!= 0
1540 || LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo
))
1542 if (dump_enabled_p ())
1543 dump_printf_loc (MSG_NOTE
, vect_location
, "epilog loop required.");
1544 if (!vect_can_advance_ivs_p (loop_vinfo
))
1546 if (dump_enabled_p ())
1547 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1548 "not vectorized: can't create epilog loop 1.");
1551 if (!slpeel_can_duplicate_loop_p (loop
, single_exit (loop
)))
1553 if (dump_enabled_p ())
1554 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1555 "not vectorized: can't create epilog loop 2.");
1564 /* Function vect_analyze_loop_2.
1566 Apply a set of analyses on LOOP, and create a loop_vec_info struct
1567 for it. The different analyses will record information in the
1568 loop_vec_info struct. */
1570 vect_analyze_loop_2 (loop_vec_info loop_vinfo
)
1572 bool ok
, slp
= false;
1573 int max_vf
= MAX_VECTORIZATION_FACTOR
;
1576 /* Find all data references in the loop (which correspond to vdefs/vuses)
1577 and analyze their evolution in the loop. Also adjust the minimal
1578 vectorization factor according to the loads and stores.
1580 FORNOW: Handle only simple, array references, which
1581 alignment can be forced, and aligned pointer-references. */
1583 ok
= vect_analyze_data_refs (loop_vinfo
, NULL
, &min_vf
);
1586 if (dump_enabled_p ())
1587 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1588 "bad data references.");
1592 /* Classify all cross-iteration scalar data-flow cycles.
1593 Cross-iteration cycles caused by virtual phis are analyzed separately. */
1595 vect_analyze_scalar_cycles (loop_vinfo
);
1597 vect_pattern_recog (loop_vinfo
, NULL
);
1599 /* Data-flow analysis to detect stmts that do not need to be vectorized. */
1601 ok
= vect_mark_stmts_to_be_vectorized (loop_vinfo
);
1604 if (dump_enabled_p ())
1605 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1606 "unexpected pattern.");
1610 /* Analyze data dependences between the data-refs in the loop
1611 and adjust the maximum vectorization factor according to
1613 FORNOW: fail at the first data dependence that we encounter. */
1615 ok
= vect_analyze_data_ref_dependences (loop_vinfo
, NULL
, &max_vf
);
1619 if (dump_enabled_p ())
1620 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1621 "bad data dependence.");
1625 ok
= vect_determine_vectorization_factor (loop_vinfo
);
1628 if (dump_enabled_p ())
1629 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1630 "can't determine vectorization factor.");
1633 if (max_vf
< LOOP_VINFO_VECT_FACTOR (loop_vinfo
))
1635 if (dump_enabled_p ())
1636 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1637 "bad data dependence.");
1641 /* Analyze the alignment of the data-refs in the loop.
1642 Fail if a data reference is found that cannot be vectorized. */
1644 ok
= vect_analyze_data_refs_alignment (loop_vinfo
, NULL
);
1647 if (dump_enabled_p ())
1648 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1649 "bad data alignment.");
1653 /* Analyze the access patterns of the data-refs in the loop (consecutive,
1654 complex, etc.). FORNOW: Only handle consecutive access pattern. */
1656 ok
= vect_analyze_data_ref_accesses (loop_vinfo
, NULL
);
1659 if (dump_enabled_p ())
1660 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1661 "bad data access.");
1665 /* Prune the list of ddrs to be tested at run-time by versioning for alias.
1666 It is important to call pruning after vect_analyze_data_ref_accesses,
1667 since we use grouping information gathered by interleaving analysis. */
1668 ok
= vect_prune_runtime_alias_test_list (loop_vinfo
);
1671 if (dump_enabled_p ())
1672 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1673 "too long list of versioning for alias "
1678 /* This pass will decide on using loop versioning and/or loop peeling in
1679 order to enhance the alignment of data references in the loop. */
1681 ok
= vect_enhance_data_refs_alignment (loop_vinfo
);
1684 if (dump_enabled_p ())
1685 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1686 "bad data alignment.");
1690 /* Check the SLP opportunities in the loop, analyze and build SLP trees. */
1691 ok
= vect_analyze_slp (loop_vinfo
, NULL
);
1694 /* Decide which possible SLP instances to SLP. */
1695 slp
= vect_make_slp_decision (loop_vinfo
);
1697 /* Find stmts that need to be both vectorized and SLPed. */
1698 vect_detect_hybrid_slp (loop_vinfo
);
1703 /* Scan all the operations in the loop and make sure they are
1706 ok
= vect_analyze_loop_operations (loop_vinfo
, slp
);
1709 if (dump_enabled_p ())
1710 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1711 "bad operation or unsupported loop bound.");
1718 /* Function vect_analyze_loop.
1720 Apply a set of analyses on LOOP, and create a loop_vec_info struct
1721 for it. The different analyses will record information in the
1722 loop_vec_info struct. */
1724 vect_analyze_loop (struct loop
*loop
)
1726 loop_vec_info loop_vinfo
;
1727 unsigned int vector_sizes
;
1729 /* Autodetect first vector size we try. */
1730 current_vector_size
= 0;
1731 vector_sizes
= targetm
.vectorize
.autovectorize_vector_sizes ();
1733 if (dump_enabled_p ())
1734 dump_printf_loc (MSG_NOTE
, vect_location
,
1735 "===== analyze_loop_nest =====");
1737 if (loop_outer (loop
)
1738 && loop_vec_info_for_loop (loop_outer (loop
))
1739 && LOOP_VINFO_VECTORIZABLE_P (loop_vec_info_for_loop (loop_outer (loop
))))
1741 if (dump_enabled_p ())
1742 dump_printf_loc (MSG_NOTE
, vect_location
,
1743 "outer-loop already vectorized.");
1749 /* Check the CFG characteristics of the loop (nesting, entry/exit). */
1750 loop_vinfo
= vect_analyze_loop_form (loop
);
1753 if (dump_enabled_p ())
1754 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
1759 if (vect_analyze_loop_2 (loop_vinfo
))
1761 LOOP_VINFO_VECTORIZABLE_P (loop_vinfo
) = 1;
1766 destroy_loop_vec_info (loop_vinfo
, true);
1768 vector_sizes
&= ~current_vector_size
;
1769 if (vector_sizes
== 0
1770 || current_vector_size
== 0)
1773 /* Try the next biggest vector size. */
1774 current_vector_size
= 1 << floor_log2 (vector_sizes
);
1775 if (dump_enabled_p ())
1776 dump_printf_loc (MSG_NOTE
, vect_location
,
1777 "***** Re-trying analysis with "
1778 "vector size %d\n", current_vector_size
);
1783 /* Function reduction_code_for_scalar_code
1786 CODE - tree_code of a reduction operations.
1789 REDUC_CODE - the corresponding tree-code to be used to reduce the
1790 vector of partial results into a single scalar result (which
1791 will also reside in a vector) or ERROR_MARK if the operation is
1792 a supported reduction operation, but does not have such tree-code.
1794 Return FALSE if CODE currently cannot be vectorized as reduction. */
1797 reduction_code_for_scalar_code (enum tree_code code
,
1798 enum tree_code
*reduc_code
)
1803 *reduc_code
= REDUC_MAX_EXPR
;
1807 *reduc_code
= REDUC_MIN_EXPR
;
1811 *reduc_code
= REDUC_PLUS_EXPR
;
1819 *reduc_code
= ERROR_MARK
;
1828 /* Error reporting helper for vect_is_simple_reduction below. GIMPLE statement
1829 STMT is printed with a message MSG. */
1832 report_vect_op (int msg_type
, gimple stmt
, const char *msg
)
1834 dump_printf_loc (msg_type
, vect_location
, "%s", msg
);
1835 dump_gimple_stmt (msg_type
, TDF_SLIM
, stmt
, 0);
1839 /* Detect SLP reduction of the form:
1849 PHI is the reduction phi node (#a1 = phi <a5, a0> above)
1850 FIRST_STMT is the first reduction stmt in the chain
1851 (a2 = operation (a1)).
1853 Return TRUE if a reduction chain was detected. */
1856 vect_is_slp_reduction (loop_vec_info loop_info
, gimple phi
, gimple first_stmt
)
1858 struct loop
*loop
= (gimple_bb (phi
))->loop_father
;
1859 struct loop
*vect_loop
= LOOP_VINFO_LOOP (loop_info
);
1860 enum tree_code code
;
1861 gimple current_stmt
= NULL
, loop_use_stmt
= NULL
, first
, next_stmt
;
1862 stmt_vec_info use_stmt_info
, current_stmt_info
;
1864 imm_use_iterator imm_iter
;
1865 use_operand_p use_p
;
1866 int nloop_uses
, size
= 0, n_out_of_loop_uses
;
1869 if (loop
!= vect_loop
)
1872 lhs
= PHI_RESULT (phi
);
1873 code
= gimple_assign_rhs_code (first_stmt
);
1877 n_out_of_loop_uses
= 0;
1878 FOR_EACH_IMM_USE_FAST (use_p
, imm_iter
, lhs
)
1880 gimple use_stmt
= USE_STMT (use_p
);
1881 if (is_gimple_debug (use_stmt
))
1884 use_stmt
= USE_STMT (use_p
);
1886 /* Check if we got back to the reduction phi. */
1887 if (use_stmt
== phi
)
1889 loop_use_stmt
= use_stmt
;
1894 if (flow_bb_inside_loop_p (loop
, gimple_bb (use_stmt
)))
1896 if (vinfo_for_stmt (use_stmt
)
1897 && !STMT_VINFO_IN_PATTERN_P (vinfo_for_stmt (use_stmt
)))
1899 loop_use_stmt
= use_stmt
;
1904 n_out_of_loop_uses
++;
1906 /* There are can be either a single use in the loop or two uses in
1908 if (nloop_uses
> 1 || (n_out_of_loop_uses
&& nloop_uses
))
1915 /* We reached a statement with no loop uses. */
1916 if (nloop_uses
== 0)
1919 /* This is a loop exit phi, and we haven't reached the reduction phi. */
1920 if (gimple_code (loop_use_stmt
) == GIMPLE_PHI
)
1923 if (!is_gimple_assign (loop_use_stmt
)
1924 || code
!= gimple_assign_rhs_code (loop_use_stmt
)
1925 || !flow_bb_inside_loop_p (loop
, gimple_bb (loop_use_stmt
)))
1928 /* Insert USE_STMT into reduction chain. */
1929 use_stmt_info
= vinfo_for_stmt (loop_use_stmt
);
1932 current_stmt_info
= vinfo_for_stmt (current_stmt
);
1933 GROUP_NEXT_ELEMENT (current_stmt_info
) = loop_use_stmt
;
1934 GROUP_FIRST_ELEMENT (use_stmt_info
)
1935 = GROUP_FIRST_ELEMENT (current_stmt_info
);
1938 GROUP_FIRST_ELEMENT (use_stmt_info
) = loop_use_stmt
;
1940 lhs
= gimple_assign_lhs (loop_use_stmt
);
1941 current_stmt
= loop_use_stmt
;
1945 if (!found
|| loop_use_stmt
!= phi
|| size
< 2)
1948 /* Swap the operands, if needed, to make the reduction operand be the second
1950 lhs
= PHI_RESULT (phi
);
1951 next_stmt
= GROUP_FIRST_ELEMENT (vinfo_for_stmt (current_stmt
));
1954 if (gimple_assign_rhs2 (next_stmt
) == lhs
)
1956 tree op
= gimple_assign_rhs1 (next_stmt
);
1957 gimple def_stmt
= NULL
;
1959 if (TREE_CODE (op
) == SSA_NAME
)
1960 def_stmt
= SSA_NAME_DEF_STMT (op
);
1962 /* Check that the other def is either defined in the loop
1963 ("vect_internal_def"), or it's an induction (defined by a
1964 loop-header phi-node). */
1966 && gimple_bb (def_stmt
)
1967 && flow_bb_inside_loop_p (loop
, gimple_bb (def_stmt
))
1968 && (is_gimple_assign (def_stmt
)
1969 || is_gimple_call (def_stmt
)
1970 || STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def_stmt
))
1971 == vect_induction_def
1972 || (gimple_code (def_stmt
) == GIMPLE_PHI
1973 && STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def_stmt
))
1974 == vect_internal_def
1975 && !is_loop_header_bb_p (gimple_bb (def_stmt
)))))
1977 lhs
= gimple_assign_lhs (next_stmt
);
1978 next_stmt
= GROUP_NEXT_ELEMENT (vinfo_for_stmt (next_stmt
));
1986 tree op
= gimple_assign_rhs2 (next_stmt
);
1987 gimple def_stmt
= NULL
;
1989 if (TREE_CODE (op
) == SSA_NAME
)
1990 def_stmt
= SSA_NAME_DEF_STMT (op
);
1992 /* Check that the other def is either defined in the loop
1993 ("vect_internal_def"), or it's an induction (defined by a
1994 loop-header phi-node). */
1996 && gimple_bb (def_stmt
)
1997 && flow_bb_inside_loop_p (loop
, gimple_bb (def_stmt
))
1998 && (is_gimple_assign (def_stmt
)
1999 || is_gimple_call (def_stmt
)
2000 || STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def_stmt
))
2001 == vect_induction_def
2002 || (gimple_code (def_stmt
) == GIMPLE_PHI
2003 && STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def_stmt
))
2004 == vect_internal_def
2005 && !is_loop_header_bb_p (gimple_bb (def_stmt
)))))
2007 if (dump_enabled_p ())
2009 dump_printf_loc (MSG_NOTE
, vect_location
, "swapping oprnds: ");
2010 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, next_stmt
, 0);
2013 swap_tree_operands (next_stmt
,
2014 gimple_assign_rhs1_ptr (next_stmt
),
2015 gimple_assign_rhs2_ptr (next_stmt
));
2016 update_stmt (next_stmt
);
2018 if (CONSTANT_CLASS_P (gimple_assign_rhs1 (next_stmt
)))
2019 LOOP_VINFO_OPERANDS_SWAPPED (loop_info
) = true;
2025 lhs
= gimple_assign_lhs (next_stmt
);
2026 next_stmt
= GROUP_NEXT_ELEMENT (vinfo_for_stmt (next_stmt
));
2029 /* Save the chain for further analysis in SLP detection. */
2030 first
= GROUP_FIRST_ELEMENT (vinfo_for_stmt (current_stmt
));
2031 LOOP_VINFO_REDUCTION_CHAINS (loop_info
).safe_push (first
);
2032 GROUP_SIZE (vinfo_for_stmt (first
)) = size
;
2038 /* Function vect_is_simple_reduction_1
2040 (1) Detect a cross-iteration def-use cycle that represents a simple
2041 reduction computation. We look for the following pattern:
2046 a2 = operation (a3, a1)
2049 1. operation is commutative and associative and it is safe to
2050 change the order of the computation (if CHECK_REDUCTION is true)
2051 2. no uses for a2 in the loop (a2 is used out of the loop)
2052 3. no uses of a1 in the loop besides the reduction operation
2053 4. no uses of a1 outside the loop.
2055 Conditions 1,4 are tested here.
2056 Conditions 2,3 are tested in vect_mark_stmts_to_be_vectorized.
2058 (2) Detect a cross-iteration def-use cycle in nested loops, i.e.,
2059 nested cycles, if CHECK_REDUCTION is false.
2061 (3) Detect cycles of phi nodes in outer-loop vectorization, i.e., double
2065 inner loop (def of a3)
2068 If MODIFY is true it tries also to rework the code in-place to enable
2069 detection of more reduction patterns. For the time being we rewrite
2070 "res -= RHS" into "rhs += -RHS" when it seems worthwhile.
2074 vect_is_simple_reduction_1 (loop_vec_info loop_info
, gimple phi
,
2075 bool check_reduction
, bool *double_reduc
,
2078 struct loop
*loop
= (gimple_bb (phi
))->loop_father
;
2079 struct loop
*vect_loop
= LOOP_VINFO_LOOP (loop_info
);
2080 edge latch_e
= loop_latch_edge (loop
);
2081 tree loop_arg
= PHI_ARG_DEF_FROM_EDGE (phi
, latch_e
);
2082 gimple def_stmt
, def1
= NULL
, def2
= NULL
;
2083 enum tree_code orig_code
, code
;
2084 tree op1
, op2
, op3
= NULL_TREE
, op4
= NULL_TREE
;
2088 imm_use_iterator imm_iter
;
2089 use_operand_p use_p
;
2092 *double_reduc
= false;
2094 /* If CHECK_REDUCTION is true, we assume inner-most loop vectorization,
2095 otherwise, we assume outer loop vectorization. */
2096 gcc_assert ((check_reduction
&& loop
== vect_loop
)
2097 || (!check_reduction
&& flow_loop_nested_p (vect_loop
, loop
)));
2099 name
= PHI_RESULT (phi
);
2101 FOR_EACH_IMM_USE_FAST (use_p
, imm_iter
, name
)
2103 gimple use_stmt
= USE_STMT (use_p
);
2104 if (is_gimple_debug (use_stmt
))
2107 if (!flow_bb_inside_loop_p (loop
, gimple_bb (use_stmt
)))
2109 if (dump_enabled_p ())
2110 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
2111 "intermediate value used outside loop.");
2116 if (vinfo_for_stmt (use_stmt
)
2117 && !is_pattern_stmt_p (vinfo_for_stmt (use_stmt
)))
2121 if (dump_enabled_p ())
2122 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
2123 "reduction used in loop.");
2128 if (TREE_CODE (loop_arg
) != SSA_NAME
)
2130 if (dump_enabled_p ())
2132 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
2133 "reduction: not ssa_name: ");
2134 dump_generic_expr (MSG_MISSED_OPTIMIZATION
, TDF_SLIM
, loop_arg
);
2139 def_stmt
= SSA_NAME_DEF_STMT (loop_arg
);
2142 if (dump_enabled_p ())
2143 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
2144 "reduction: no def_stmt.");
2148 if (!is_gimple_assign (def_stmt
) && gimple_code (def_stmt
) != GIMPLE_PHI
)
2150 if (dump_enabled_p ())
2151 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, def_stmt
, 0);
2155 if (is_gimple_assign (def_stmt
))
2157 name
= gimple_assign_lhs (def_stmt
);
2162 name
= PHI_RESULT (def_stmt
);
2167 FOR_EACH_IMM_USE_FAST (use_p
, imm_iter
, name
)
2169 gimple use_stmt
= USE_STMT (use_p
);
2170 if (is_gimple_debug (use_stmt
))
2172 if (flow_bb_inside_loop_p (loop
, gimple_bb (use_stmt
))
2173 && vinfo_for_stmt (use_stmt
)
2174 && !is_pattern_stmt_p (vinfo_for_stmt (use_stmt
)))
2178 if (dump_enabled_p ())
2179 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
2180 "reduction used in loop.");
2185 /* If DEF_STMT is a phi node itself, we expect it to have a single argument
2186 defined in the inner loop. */
2189 op1
= PHI_ARG_DEF (def_stmt
, 0);
2191 if (gimple_phi_num_args (def_stmt
) != 1
2192 || TREE_CODE (op1
) != SSA_NAME
)
2194 if (dump_enabled_p ())
2195 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
2196 "unsupported phi node definition.");
2201 def1
= SSA_NAME_DEF_STMT (op1
);
2202 if (flow_bb_inside_loop_p (loop
, gimple_bb (def_stmt
))
2204 && flow_bb_inside_loop_p (loop
->inner
, gimple_bb (def1
))
2205 && is_gimple_assign (def1
))
2207 if (dump_enabled_p ())
2208 report_vect_op (MSG_NOTE
, def_stmt
,
2209 "detected double reduction: ");
2211 *double_reduc
= true;
2218 code
= orig_code
= gimple_assign_rhs_code (def_stmt
);
2220 /* We can handle "res -= x[i]", which is non-associative by
2221 simply rewriting this into "res += -x[i]". Avoid changing
2222 gimple instruction for the first simple tests and only do this
2223 if we're allowed to change code at all. */
2224 if (code
== MINUS_EXPR
2226 && (op1
= gimple_assign_rhs1 (def_stmt
))
2227 && TREE_CODE (op1
) == SSA_NAME
2228 && SSA_NAME_DEF_STMT (op1
) == phi
)
2232 && (!commutative_tree_code (code
) || !associative_tree_code (code
)))
2234 if (dump_enabled_p ())
2235 report_vect_op (MSG_MISSED_OPTIMIZATION
, def_stmt
,
2236 "reduction: not commutative/associative: ");
2240 if (get_gimple_rhs_class (code
) != GIMPLE_BINARY_RHS
)
2242 if (code
!= COND_EXPR
)
2244 if (dump_enabled_p ())
2245 report_vect_op (MSG_MISSED_OPTIMIZATION
, def_stmt
,
2246 "reduction: not binary operation: ");
2251 op3
= gimple_assign_rhs1 (def_stmt
);
2252 if (COMPARISON_CLASS_P (op3
))
2254 op4
= TREE_OPERAND (op3
, 1);
2255 op3
= TREE_OPERAND (op3
, 0);
2258 op1
= gimple_assign_rhs2 (def_stmt
);
2259 op2
= gimple_assign_rhs3 (def_stmt
);
2261 if (TREE_CODE (op1
) != SSA_NAME
&& TREE_CODE (op2
) != SSA_NAME
)
2263 if (dump_enabled_p ())
2264 report_vect_op (MSG_MISSED_OPTIMIZATION
, def_stmt
,
2265 "reduction: uses not ssa_names: ");
2272 op1
= gimple_assign_rhs1 (def_stmt
);
2273 op2
= gimple_assign_rhs2 (def_stmt
);
2275 if (TREE_CODE (op1
) != SSA_NAME
&& TREE_CODE (op2
) != SSA_NAME
)
2277 if (dump_enabled_p ())
2278 report_vect_op (MSG_MISSED_OPTIMIZATION
, def_stmt
,
2279 "reduction: uses not ssa_names: ");
2285 type
= TREE_TYPE (gimple_assign_lhs (def_stmt
));
2286 if ((TREE_CODE (op1
) == SSA_NAME
2287 && !types_compatible_p (type
,TREE_TYPE (op1
)))
2288 || (TREE_CODE (op2
) == SSA_NAME
2289 && !types_compatible_p (type
, TREE_TYPE (op2
)))
2290 || (op3
&& TREE_CODE (op3
) == SSA_NAME
2291 && !types_compatible_p (type
, TREE_TYPE (op3
)))
2292 || (op4
&& TREE_CODE (op4
) == SSA_NAME
2293 && !types_compatible_p (type
, TREE_TYPE (op4
))))
2295 if (dump_enabled_p ())
2297 dump_printf_loc (MSG_NOTE
, vect_location
,
2298 "reduction: multiple types: operation type: ");
2299 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, type
);
2300 dump_printf (MSG_NOTE
, ", operands types: ");
2301 dump_generic_expr (MSG_NOTE
, TDF_SLIM
,
2303 dump_printf (MSG_NOTE
, ",");
2304 dump_generic_expr (MSG_NOTE
, TDF_SLIM
,
2308 dump_printf (MSG_NOTE
, ",");
2309 dump_generic_expr (MSG_NOTE
, TDF_SLIM
,
2315 dump_printf (MSG_NOTE
, ",");
2316 dump_generic_expr (MSG_NOTE
, TDF_SLIM
,
2324 /* Check that it's ok to change the order of the computation.
2325 Generally, when vectorizing a reduction we change the order of the
2326 computation. This may change the behavior of the program in some
2327 cases, so we need to check that this is ok. One exception is when
2328 vectorizing an outer-loop: the inner-loop is executed sequentially,
2329 and therefore vectorizing reductions in the inner-loop during
2330 outer-loop vectorization is safe. */
2332 /* CHECKME: check for !flag_finite_math_only too? */
2333 if (SCALAR_FLOAT_TYPE_P (type
) && !flag_associative_math
2336 /* Changing the order of operations changes the semantics. */
2337 if (dump_enabled_p ())
2338 report_vect_op (MSG_MISSED_OPTIMIZATION
, def_stmt
,
2339 "reduction: unsafe fp math optimization: ");
2342 else if (INTEGRAL_TYPE_P (type
) && TYPE_OVERFLOW_TRAPS (type
)
2345 /* Changing the order of operations changes the semantics. */
2346 if (dump_enabled_p ())
2347 report_vect_op (MSG_MISSED_OPTIMIZATION
, def_stmt
,
2348 "reduction: unsafe int math optimization: ");
2351 else if (SAT_FIXED_POINT_TYPE_P (type
) && check_reduction
)
2353 /* Changing the order of operations changes the semantics. */
2354 if (dump_enabled_p ())
2355 report_vect_op (MSG_MISSED_OPTIMIZATION
, def_stmt
,
2356 "reduction: unsafe fixed-point math optimization: ");
2360 /* If we detected "res -= x[i]" earlier, rewrite it into
2361 "res += -x[i]" now. If this turns out to be useless reassoc
2362 will clean it up again. */
2363 if (orig_code
== MINUS_EXPR
)
2365 tree rhs
= gimple_assign_rhs2 (def_stmt
);
2366 tree negrhs
= make_ssa_name (TREE_TYPE (rhs
), NULL
);
2367 gimple negate_stmt
= gimple_build_assign_with_ops (NEGATE_EXPR
, negrhs
,
2369 gimple_stmt_iterator gsi
= gsi_for_stmt (def_stmt
);
2370 set_vinfo_for_stmt (negate_stmt
, new_stmt_vec_info (negate_stmt
,
2372 gsi_insert_before (&gsi
, negate_stmt
, GSI_NEW_STMT
);
2373 gimple_assign_set_rhs2 (def_stmt
, negrhs
);
2374 gimple_assign_set_rhs_code (def_stmt
, PLUS_EXPR
);
2375 update_stmt (def_stmt
);
2378 /* Reduction is safe. We're dealing with one of the following:
2379 1) integer arithmetic and no trapv
2380 2) floating point arithmetic, and special flags permit this optimization
2381 3) nested cycle (i.e., outer loop vectorization). */
2382 if (TREE_CODE (op1
) == SSA_NAME
)
2383 def1
= SSA_NAME_DEF_STMT (op1
);
2385 if (TREE_CODE (op2
) == SSA_NAME
)
2386 def2
= SSA_NAME_DEF_STMT (op2
);
2388 if (code
!= COND_EXPR
2389 && ((!def1
|| gimple_nop_p (def1
)) && (!def2
|| gimple_nop_p (def2
))))
2391 if (dump_enabled_p ())
2392 report_vect_op (MSG_NOTE
, def_stmt
, "reduction: no defs for operands: ");
2396 /* Check that one def is the reduction def, defined by PHI,
2397 the other def is either defined in the loop ("vect_internal_def"),
2398 or it's an induction (defined by a loop-header phi-node). */
2400 if (def2
&& def2
== phi
2401 && (code
== COND_EXPR
2402 || !def1
|| gimple_nop_p (def1
)
2403 || (def1
&& flow_bb_inside_loop_p (loop
, gimple_bb (def1
))
2404 && (is_gimple_assign (def1
)
2405 || is_gimple_call (def1
)
2406 || STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def1
))
2407 == vect_induction_def
2408 || (gimple_code (def1
) == GIMPLE_PHI
2409 && STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def1
))
2410 == vect_internal_def
2411 && !is_loop_header_bb_p (gimple_bb (def1
)))))))
2413 if (dump_enabled_p ())
2414 report_vect_op (MSG_NOTE
, def_stmt
, "detected reduction: ");
2418 if (def1
&& def1
== phi
2419 && (code
== COND_EXPR
2420 || !def2
|| gimple_nop_p (def2
)
2421 || (def2
&& flow_bb_inside_loop_p (loop
, gimple_bb (def2
))
2422 && (is_gimple_assign (def2
)
2423 || is_gimple_call (def2
)
2424 || STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def2
))
2425 == vect_induction_def
2426 || (gimple_code (def2
) == GIMPLE_PHI
2427 && STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def2
))
2428 == vect_internal_def
2429 && !is_loop_header_bb_p (gimple_bb (def2
)))))))
2431 if (check_reduction
)
2433 /* Swap operands (just for simplicity - so that the rest of the code
2434 can assume that the reduction variable is always the last (second)
2436 if (dump_enabled_p ())
2437 report_vect_op (MSG_NOTE
, def_stmt
,
2438 "detected reduction: need to swap operands: ");
2440 swap_tree_operands (def_stmt
, gimple_assign_rhs1_ptr (def_stmt
),
2441 gimple_assign_rhs2_ptr (def_stmt
));
2443 if (CONSTANT_CLASS_P (gimple_assign_rhs1 (def_stmt
)))
2444 LOOP_VINFO_OPERANDS_SWAPPED (loop_info
) = true;
2448 if (dump_enabled_p ())
2449 report_vect_op (MSG_NOTE
, def_stmt
, "detected reduction: ");
2455 /* Try to find SLP reduction chain. */
2456 if (check_reduction
&& vect_is_slp_reduction (loop_info
, phi
, def_stmt
))
2458 if (dump_enabled_p ())
2459 report_vect_op (MSG_NOTE
, def_stmt
,
2460 "reduction: detected reduction chain: ");
2465 if (dump_enabled_p ())
2466 report_vect_op (MSG_MISSED_OPTIMIZATION
, def_stmt
,
2467 "reduction: unknown pattern: ");
2472 /* Wrapper around vect_is_simple_reduction_1, that won't modify code
2473 in-place. Arguments as there. */
2476 vect_is_simple_reduction (loop_vec_info loop_info
, gimple phi
,
2477 bool check_reduction
, bool *double_reduc
)
2479 return vect_is_simple_reduction_1 (loop_info
, phi
, check_reduction
,
2480 double_reduc
, false);
2483 /* Wrapper around vect_is_simple_reduction_1, which will modify code
2484 in-place if it enables detection of more reductions. Arguments
2488 vect_force_simple_reduction (loop_vec_info loop_info
, gimple phi
,
2489 bool check_reduction
, bool *double_reduc
)
2491 return vect_is_simple_reduction_1 (loop_info
, phi
, check_reduction
,
2492 double_reduc
, true);
2495 /* Calculate the cost of one scalar iteration of the loop. */
2497 vect_get_single_scalar_iteration_cost (loop_vec_info loop_vinfo
)
2499 struct loop
*loop
= LOOP_VINFO_LOOP (loop_vinfo
);
2500 basic_block
*bbs
= LOOP_VINFO_BBS (loop_vinfo
);
2501 int nbbs
= loop
->num_nodes
, factor
, scalar_single_iter_cost
= 0;
2502 int innerloop_iters
, i
, stmt_cost
;
2504 /* Count statements in scalar loop. Using this as scalar cost for a single
2507 TODO: Add outer loop support.
2509 TODO: Consider assigning different costs to different scalar
2513 innerloop_iters
= 1;
2515 innerloop_iters
= 50; /* FIXME */
2517 for (i
= 0; i
< nbbs
; i
++)
2519 gimple_stmt_iterator si
;
2520 basic_block bb
= bbs
[i
];
2522 if (bb
->loop_father
== loop
->inner
)
2523 factor
= innerloop_iters
;
2527 for (si
= gsi_start_bb (bb
); !gsi_end_p (si
); gsi_next (&si
))
2529 gimple stmt
= gsi_stmt (si
);
2530 stmt_vec_info stmt_info
= vinfo_for_stmt (stmt
);
2532 if (!is_gimple_assign (stmt
) && !is_gimple_call (stmt
))
2535 /* Skip stmts that are not vectorized inside the loop. */
2537 && !STMT_VINFO_RELEVANT_P (stmt_info
)
2538 && (!STMT_VINFO_LIVE_P (stmt_info
)
2539 || !VECTORIZABLE_CYCLE_DEF (STMT_VINFO_DEF_TYPE (stmt_info
)))
2540 && !STMT_VINFO_IN_PATTERN_P (stmt_info
))
2543 if (STMT_VINFO_DATA_REF (vinfo_for_stmt (stmt
)))
2545 if (DR_IS_READ (STMT_VINFO_DATA_REF (vinfo_for_stmt (stmt
))))
2546 stmt_cost
= vect_get_stmt_cost (scalar_load
);
2548 stmt_cost
= vect_get_stmt_cost (scalar_store
);
2551 stmt_cost
= vect_get_stmt_cost (scalar_stmt
);
2553 scalar_single_iter_cost
+= stmt_cost
* factor
;
2556 return scalar_single_iter_cost
;
2559 /* Calculate cost of peeling the loop PEEL_ITERS_PROLOGUE times. */
2561 vect_get_known_peeling_cost (loop_vec_info loop_vinfo
, int peel_iters_prologue
,
2562 int *peel_iters_epilogue
,
2563 int scalar_single_iter_cost
,
2564 stmt_vector_for_cost
*prologue_cost_vec
,
2565 stmt_vector_for_cost
*epilogue_cost_vec
)
2568 int vf
= LOOP_VINFO_VECT_FACTOR (loop_vinfo
);
2570 if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo
))
2572 *peel_iters_epilogue
= vf
/2;
2573 if (dump_enabled_p ())
2574 dump_printf_loc (MSG_NOTE
, vect_location
,
2575 "cost model: epilogue peel iters set to vf/2 "
2576 "because loop iterations are unknown .");
2578 /* If peeled iterations are known but number of scalar loop
2579 iterations are unknown, count a taken branch per peeled loop. */
2580 retval
= record_stmt_cost (prologue_cost_vec
, 2, cond_branch_taken
,
2581 NULL
, 0, vect_prologue
);
2585 int niters
= LOOP_VINFO_INT_NITERS (loop_vinfo
);
2586 peel_iters_prologue
= niters
< peel_iters_prologue
?
2587 niters
: peel_iters_prologue
;
2588 *peel_iters_epilogue
= (niters
- peel_iters_prologue
) % vf
;
2589 /* If we need to peel for gaps, but no peeling is required, we have to
2590 peel VF iterations. */
2591 if (LOOP_VINFO_PEELING_FOR_GAPS (loop_vinfo
) && !*peel_iters_epilogue
)
2592 *peel_iters_epilogue
= vf
;
2595 if (peel_iters_prologue
)
2596 retval
+= record_stmt_cost (prologue_cost_vec
,
2597 peel_iters_prologue
* scalar_single_iter_cost
,
2598 scalar_stmt
, NULL
, 0, vect_prologue
);
2599 if (*peel_iters_epilogue
)
2600 retval
+= record_stmt_cost (epilogue_cost_vec
,
2601 *peel_iters_epilogue
* scalar_single_iter_cost
,
2602 scalar_stmt
, NULL
, 0, vect_epilogue
);
2606 /* Function vect_estimate_min_profitable_iters
2608 Return the number of iterations required for the vector version of the
2609 loop to be profitable relative to the cost of the scalar version of the
2613 vect_estimate_min_profitable_iters (loop_vec_info loop_vinfo
,
2614 int *ret_min_profitable_niters
,
2615 int *ret_min_profitable_estimate
)
2617 int min_profitable_iters
;
2618 int min_profitable_estimate
;
2619 int peel_iters_prologue
;
2620 int peel_iters_epilogue
;
2621 unsigned vec_inside_cost
= 0;
2622 int vec_outside_cost
= 0;
2623 unsigned vec_prologue_cost
= 0;
2624 unsigned vec_epilogue_cost
= 0;
2625 int scalar_single_iter_cost
= 0;
2626 int scalar_outside_cost
= 0;
2627 int vf
= LOOP_VINFO_VECT_FACTOR (loop_vinfo
);
2628 int npeel
= LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo
);
2629 void *target_cost_data
= LOOP_VINFO_TARGET_COST_DATA (loop_vinfo
);
2631 /* Cost model disabled. */
2632 if (!flag_vect_cost_model
)
2634 dump_printf_loc (MSG_NOTE
, vect_location
, "cost model disabled.");
2635 *ret_min_profitable_niters
= 0;
2636 *ret_min_profitable_estimate
= 0;
2640 /* Requires loop versioning tests to handle misalignment. */
2641 if (LOOP_REQUIRES_VERSIONING_FOR_ALIGNMENT (loop_vinfo
))
2643 /* FIXME: Make cost depend on complexity of individual check. */
2644 unsigned len
= LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo
).length ();
2645 (void) add_stmt_cost (target_cost_data
, len
, vector_stmt
, NULL
, 0,
2647 dump_printf (MSG_NOTE
,
2648 "cost model: Adding cost of checks for loop "
2649 "versioning to treat misalignment.\n");
2652 /* Requires loop versioning with alias checks. */
2653 if (LOOP_REQUIRES_VERSIONING_FOR_ALIAS (loop_vinfo
))
2655 /* FIXME: Make cost depend on complexity of individual check. */
2656 unsigned len
= LOOP_VINFO_MAY_ALIAS_DDRS (loop_vinfo
).length ();
2657 (void) add_stmt_cost (target_cost_data
, len
, vector_stmt
, NULL
, 0,
2659 dump_printf (MSG_NOTE
,
2660 "cost model: Adding cost of checks for loop "
2661 "versioning aliasing.\n");
2664 if (LOOP_REQUIRES_VERSIONING_FOR_ALIGNMENT (loop_vinfo
)
2665 || LOOP_REQUIRES_VERSIONING_FOR_ALIAS (loop_vinfo
))
2666 (void) add_stmt_cost (target_cost_data
, 1, cond_branch_taken
, NULL
, 0,
2669 /* Count statements in scalar loop. Using this as scalar cost for a single
2672 TODO: Add outer loop support.
2674 TODO: Consider assigning different costs to different scalar
2677 scalar_single_iter_cost
= vect_get_single_scalar_iteration_cost (loop_vinfo
);
2679 /* Add additional cost for the peeled instructions in prologue and epilogue
2682 FORNOW: If we don't know the value of peel_iters for prologue or epilogue
2683 at compile-time - we assume it's vf/2 (the worst would be vf-1).
2685 TODO: Build an expression that represents peel_iters for prologue and
2686 epilogue to be used in a run-time test. */
2690 peel_iters_prologue
= vf
/2;
2691 dump_printf (MSG_NOTE
, "cost model: "
2692 "prologue peel iters set to vf/2.");
2694 /* If peeling for alignment is unknown, loop bound of main loop becomes
2696 peel_iters_epilogue
= vf
/2;
2697 dump_printf (MSG_NOTE
, "cost model: "
2698 "epilogue peel iters set to vf/2 because "
2699 "peeling for alignment is unknown.");
2701 /* If peeled iterations are unknown, count a taken branch and a not taken
2702 branch per peeled loop. Even if scalar loop iterations are known,
2703 vector iterations are not known since peeled prologue iterations are
2704 not known. Hence guards remain the same. */
2705 (void) add_stmt_cost (target_cost_data
, 2, cond_branch_taken
,
2706 NULL
, 0, vect_prologue
);
2707 (void) add_stmt_cost (target_cost_data
, 2, cond_branch_not_taken
,
2708 NULL
, 0, vect_prologue
);
2709 /* FORNOW: Don't attempt to pass individual scalar instructions to
2710 the model; just assume linear cost for scalar iterations. */
2711 (void) add_stmt_cost (target_cost_data
,
2712 peel_iters_prologue
* scalar_single_iter_cost
,
2713 scalar_stmt
, NULL
, 0, vect_prologue
);
2714 (void) add_stmt_cost (target_cost_data
,
2715 peel_iters_epilogue
* scalar_single_iter_cost
,
2716 scalar_stmt
, NULL
, 0, vect_epilogue
);
2720 stmt_vector_for_cost prologue_cost_vec
, epilogue_cost_vec
;
2721 stmt_info_for_cost
*si
;
2723 void *data
= LOOP_VINFO_TARGET_COST_DATA (loop_vinfo
);
2725 prologue_cost_vec
.create (2);
2726 epilogue_cost_vec
.create (2);
2727 peel_iters_prologue
= npeel
;
2729 (void) vect_get_known_peeling_cost (loop_vinfo
, peel_iters_prologue
,
2730 &peel_iters_epilogue
,
2731 scalar_single_iter_cost
,
2733 &epilogue_cost_vec
);
2735 FOR_EACH_VEC_ELT (prologue_cost_vec
, j
, si
)
2737 struct _stmt_vec_info
*stmt_info
2738 = si
->stmt
? vinfo_for_stmt (si
->stmt
) : NULL
;
2739 (void) add_stmt_cost (data
, si
->count
, si
->kind
, stmt_info
,
2740 si
->misalign
, vect_prologue
);
2743 FOR_EACH_VEC_ELT (epilogue_cost_vec
, j
, si
)
2745 struct _stmt_vec_info
*stmt_info
2746 = si
->stmt
? vinfo_for_stmt (si
->stmt
) : NULL
;
2747 (void) add_stmt_cost (data
, si
->count
, si
->kind
, stmt_info
,
2748 si
->misalign
, vect_epilogue
);
2751 prologue_cost_vec
.release ();
2752 epilogue_cost_vec
.release ();
2755 /* FORNOW: The scalar outside cost is incremented in one of the
2758 1. The vectorizer checks for alignment and aliasing and generates
2759 a condition that allows dynamic vectorization. A cost model
2760 check is ANDED with the versioning condition. Hence scalar code
2761 path now has the added cost of the versioning check.
2763 if (cost > th & versioning_check)
2766 Hence run-time scalar is incremented by not-taken branch cost.
2768 2. The vectorizer then checks if a prologue is required. If the
2769 cost model check was not done before during versioning, it has to
2770 be done before the prologue check.
2773 prologue = scalar_iters
2778 if (prologue == num_iters)
2781 Hence the run-time scalar cost is incremented by a taken branch,
2782 plus a not-taken branch, plus a taken branch cost.
2784 3. The vectorizer then checks if an epilogue is required. If the
2785 cost model check was not done before during prologue check, it
2786 has to be done with the epilogue check.
2792 if (prologue == num_iters)
2795 if ((cost <= th) | (scalar_iters-prologue-epilogue == 0))
2798 Hence the run-time scalar cost should be incremented by 2 taken
2801 TODO: The back end may reorder the BBS's differently and reverse
2802 conditions/branch directions. Change the estimates below to
2803 something more reasonable. */
2805 /* If the number of iterations is known and we do not do versioning, we can
2806 decide whether to vectorize at compile time. Hence the scalar version
2807 do not carry cost model guard costs. */
2808 if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo
)
2809 || LOOP_REQUIRES_VERSIONING_FOR_ALIGNMENT (loop_vinfo
)
2810 || LOOP_REQUIRES_VERSIONING_FOR_ALIAS (loop_vinfo
))
2812 /* Cost model check occurs at versioning. */
2813 if (LOOP_REQUIRES_VERSIONING_FOR_ALIGNMENT (loop_vinfo
)
2814 || LOOP_REQUIRES_VERSIONING_FOR_ALIAS (loop_vinfo
))
2815 scalar_outside_cost
+= vect_get_stmt_cost (cond_branch_not_taken
);
2818 /* Cost model check occurs at prologue generation. */
2819 if (LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo
) < 0)
2820 scalar_outside_cost
+= 2 * vect_get_stmt_cost (cond_branch_taken
)
2821 + vect_get_stmt_cost (cond_branch_not_taken
);
2822 /* Cost model check occurs at epilogue generation. */
2824 scalar_outside_cost
+= 2 * vect_get_stmt_cost (cond_branch_taken
);
2828 /* Complete the target-specific cost calculations. */
2829 finish_cost (LOOP_VINFO_TARGET_COST_DATA (loop_vinfo
), &vec_prologue_cost
,
2830 &vec_inside_cost
, &vec_epilogue_cost
);
2832 vec_outside_cost
= (int)(vec_prologue_cost
+ vec_epilogue_cost
);
2834 /* Calculate number of iterations required to make the vector version
2835 profitable, relative to the loop bodies only. The following condition
2837 SIC * niters + SOC > VIC * ((niters-PL_ITERS-EP_ITERS)/VF) + VOC
2839 SIC = scalar iteration cost, VIC = vector iteration cost,
2840 VOC = vector outside cost, VF = vectorization factor,
2841 PL_ITERS = prologue iterations, EP_ITERS= epilogue iterations
2842 SOC = scalar outside cost for run time cost model check. */
2844 if ((scalar_single_iter_cost
* vf
) > (int) vec_inside_cost
)
2846 if (vec_outside_cost
<= 0)
2847 min_profitable_iters
= 1;
2850 min_profitable_iters
= ((vec_outside_cost
- scalar_outside_cost
) * vf
2851 - vec_inside_cost
* peel_iters_prologue
2852 - vec_inside_cost
* peel_iters_epilogue
)
2853 / ((scalar_single_iter_cost
* vf
)
2856 if ((scalar_single_iter_cost
* vf
* min_profitable_iters
)
2857 <= (((int) vec_inside_cost
* min_profitable_iters
)
2858 + (((int) vec_outside_cost
- scalar_outside_cost
) * vf
)))
2859 min_profitable_iters
++;
2862 /* vector version will never be profitable. */
2865 if (dump_enabled_p ())
2866 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
2867 "cost model: the vector iteration cost = %d "
2868 "divided by the scalar iteration cost = %d "
2869 "is greater or equal to the vectorization factor = %d.",
2870 vec_inside_cost
, scalar_single_iter_cost
, vf
);
2871 *ret_min_profitable_niters
= -1;
2872 *ret_min_profitable_estimate
= -1;
2876 if (dump_enabled_p ())
2878 dump_printf_loc (MSG_NOTE
, vect_location
, "Cost model analysis: \n");
2879 dump_printf (MSG_NOTE
, " Vector inside of loop cost: %d\n",
2881 dump_printf (MSG_NOTE
, " Vector prologue cost: %d\n",
2883 dump_printf (MSG_NOTE
, " Vector epilogue cost: %d\n",
2885 dump_printf (MSG_NOTE
, " Scalar iteration cost: %d\n",
2886 scalar_single_iter_cost
);
2887 dump_printf (MSG_NOTE
, " Scalar outside cost: %d\n",
2888 scalar_outside_cost
);
2889 dump_printf (MSG_NOTE
, " Vector outside cost: %d\n",
2891 dump_printf (MSG_NOTE
, " prologue iterations: %d\n",
2892 peel_iters_prologue
);
2893 dump_printf (MSG_NOTE
, " epilogue iterations: %d\n",
2894 peel_iters_epilogue
);
2895 dump_printf (MSG_NOTE
,
2896 " Calculated minimum iters for profitability: %d\n",
2897 min_profitable_iters
);
2900 min_profitable_iters
=
2901 min_profitable_iters
< vf
? vf
: min_profitable_iters
;
2903 /* Because the condition we create is:
2904 if (niters <= min_profitable_iters)
2905 then skip the vectorized loop. */
2906 min_profitable_iters
--;
2908 if (dump_enabled_p ())
2909 dump_printf_loc (MSG_NOTE
, vect_location
,
2910 " Runtime profitability threshold = %d\n", min_profitable_iters
);
2912 *ret_min_profitable_niters
= min_profitable_iters
;
2914 /* Calculate number of iterations required to make the vector version
2915 profitable, relative to the loop bodies only.
2917 Non-vectorized variant is SIC * niters and it must win over vector
2918 variant on the expected loop trip count. The following condition must hold true:
2919 SIC * niters > VIC * ((niters-PL_ITERS-EP_ITERS)/VF) + VOC + SOC */
2921 if (vec_outside_cost
<= 0)
2922 min_profitable_estimate
= 1;
2925 min_profitable_estimate
= ((vec_outside_cost
+ scalar_outside_cost
) * vf
2926 - vec_inside_cost
* peel_iters_prologue
2927 - vec_inside_cost
* peel_iters_epilogue
)
2928 / ((scalar_single_iter_cost
* vf
)
2931 min_profitable_estimate
--;
2932 min_profitable_estimate
= MAX (min_profitable_estimate
, min_profitable_iters
);
2933 if (dump_enabled_p ())
2934 dump_printf_loc (MSG_NOTE
, vect_location
,
2935 " Static estimate profitability threshold = %d\n",
2936 min_profitable_iters
);
2938 *ret_min_profitable_estimate
= min_profitable_estimate
;
2942 /* TODO: Close dependency between vect_model_*_cost and vectorizable_*
2943 functions. Design better to avoid maintenance issues. */
2945 /* Function vect_model_reduction_cost.
2947 Models cost for a reduction operation, including the vector ops
2948 generated within the strip-mine loop, the initial definition before
2949 the loop, and the epilogue code that must be generated. */
2952 vect_model_reduction_cost (stmt_vec_info stmt_info
, enum tree_code reduc_code
,
2955 int prologue_cost
= 0, epilogue_cost
= 0;
2956 enum tree_code code
;
2959 gimple stmt
, orig_stmt
;
2961 enum machine_mode mode
;
2962 loop_vec_info loop_vinfo
= STMT_VINFO_LOOP_VINFO (stmt_info
);
2963 struct loop
*loop
= LOOP_VINFO_LOOP (loop_vinfo
);
2964 void *target_cost_data
= LOOP_VINFO_TARGET_COST_DATA (loop_vinfo
);
2966 /* Cost of reduction op inside loop. */
2967 unsigned inside_cost
= add_stmt_cost (target_cost_data
, ncopies
, vector_stmt
,
2968 stmt_info
, 0, vect_body
);
2969 stmt
= STMT_VINFO_STMT (stmt_info
);
2971 switch (get_gimple_rhs_class (gimple_assign_rhs_code (stmt
)))
2973 case GIMPLE_SINGLE_RHS
:
2974 gcc_assert (TREE_OPERAND_LENGTH (gimple_assign_rhs1 (stmt
)) == ternary_op
);
2975 reduction_op
= TREE_OPERAND (gimple_assign_rhs1 (stmt
), 2);
2977 case GIMPLE_UNARY_RHS
:
2978 reduction_op
= gimple_assign_rhs1 (stmt
);
2980 case GIMPLE_BINARY_RHS
:
2981 reduction_op
= gimple_assign_rhs2 (stmt
);
2983 case GIMPLE_TERNARY_RHS
:
2984 reduction_op
= gimple_assign_rhs3 (stmt
);
2990 vectype
= get_vectype_for_scalar_type (TREE_TYPE (reduction_op
));
2993 if (dump_enabled_p ())
2995 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
2996 "unsupported data-type ");
2997 dump_generic_expr (MSG_MISSED_OPTIMIZATION
, TDF_SLIM
,
2998 TREE_TYPE (reduction_op
));
3003 mode
= TYPE_MODE (vectype
);
3004 orig_stmt
= STMT_VINFO_RELATED_STMT (stmt_info
);
3007 orig_stmt
= STMT_VINFO_STMT (stmt_info
);
3009 code
= gimple_assign_rhs_code (orig_stmt
);
3011 /* Add in cost for initial definition. */
3012 prologue_cost
+= add_stmt_cost (target_cost_data
, 1, scalar_to_vec
,
3013 stmt_info
, 0, vect_prologue
);
3015 /* Determine cost of epilogue code.
3017 We have a reduction operator that will reduce the vector in one statement.
3018 Also requires scalar extract. */
3020 if (!nested_in_vect_loop_p (loop
, orig_stmt
))
3022 if (reduc_code
!= ERROR_MARK
)
3024 epilogue_cost
+= add_stmt_cost (target_cost_data
, 1, vector_stmt
,
3025 stmt_info
, 0, vect_epilogue
);
3026 epilogue_cost
+= add_stmt_cost (target_cost_data
, 1, vec_to_scalar
,
3027 stmt_info
, 0, vect_epilogue
);
3031 int vec_size_in_bits
= tree_low_cst (TYPE_SIZE (vectype
), 1);
3033 TYPE_SIZE (TREE_TYPE (gimple_assign_lhs (orig_stmt
)));
3034 int element_bitsize
= tree_low_cst (bitsize
, 1);
3035 int nelements
= vec_size_in_bits
/ element_bitsize
;
3037 optab
= optab_for_tree_code (code
, vectype
, optab_default
);
3039 /* We have a whole vector shift available. */
3040 if (VECTOR_MODE_P (mode
)
3041 && optab_handler (optab
, mode
) != CODE_FOR_nothing
3042 && optab_handler (vec_shr_optab
, mode
) != CODE_FOR_nothing
)
3044 /* Final reduction via vector shifts and the reduction operator.
3045 Also requires scalar extract. */
3046 epilogue_cost
+= add_stmt_cost (target_cost_data
,
3047 exact_log2 (nelements
) * 2,
3048 vector_stmt
, stmt_info
, 0,
3050 epilogue_cost
+= add_stmt_cost (target_cost_data
, 1,
3051 vec_to_scalar
, stmt_info
, 0,
3055 /* Use extracts and reduction op for final reduction. For N
3056 elements, we have N extracts and N-1 reduction ops. */
3057 epilogue_cost
+= add_stmt_cost (target_cost_data
,
3058 nelements
+ nelements
- 1,
3059 vector_stmt
, stmt_info
, 0,
3064 if (dump_enabled_p ())
3065 dump_printf (MSG_NOTE
,
3066 "vect_model_reduction_cost: inside_cost = %d, "
3067 "prologue_cost = %d, epilogue_cost = %d .", inside_cost
,
3068 prologue_cost
, epilogue_cost
);
3074 /* Function vect_model_induction_cost.
3076 Models cost for induction operations. */
3079 vect_model_induction_cost (stmt_vec_info stmt_info
, int ncopies
)
3081 loop_vec_info loop_vinfo
= STMT_VINFO_LOOP_VINFO (stmt_info
);
3082 void *target_cost_data
= LOOP_VINFO_TARGET_COST_DATA (loop_vinfo
);
3083 unsigned inside_cost
, prologue_cost
;
3085 /* loop cost for vec_loop. */
3086 inside_cost
= add_stmt_cost (target_cost_data
, ncopies
, vector_stmt
,
3087 stmt_info
, 0, vect_body
);
3089 /* prologue cost for vec_init and vec_step. */
3090 prologue_cost
= add_stmt_cost (target_cost_data
, 2, scalar_to_vec
,
3091 stmt_info
, 0, vect_prologue
);
3093 if (dump_enabled_p ())
3094 dump_printf_loc (MSG_NOTE
, vect_location
,
3095 "vect_model_induction_cost: inside_cost = %d, "
3096 "prologue_cost = %d .", inside_cost
, prologue_cost
);
3100 /* Function get_initial_def_for_induction
3103 STMT - a stmt that performs an induction operation in the loop.
3104 IV_PHI - the initial value of the induction variable
3107 Return a vector variable, initialized with the first VF values of
3108 the induction variable. E.g., for an iv with IV_PHI='X' and
3109 evolution S, for a vector of 4 units, we want to return:
3110 [X, X + S, X + 2*S, X + 3*S]. */
3113 get_initial_def_for_induction (gimple iv_phi
)
3115 stmt_vec_info stmt_vinfo
= vinfo_for_stmt (iv_phi
);
3116 loop_vec_info loop_vinfo
= STMT_VINFO_LOOP_VINFO (stmt_vinfo
);
3117 struct loop
*loop
= LOOP_VINFO_LOOP (loop_vinfo
);
3121 edge pe
= loop_preheader_edge (loop
);
3122 struct loop
*iv_loop
;
3124 tree new_vec
, vec_init
, vec_step
, t
;
3128 gimple init_stmt
, induction_phi
, new_stmt
;
3129 tree induc_def
, vec_def
, vec_dest
;
3130 tree init_expr
, step_expr
;
3131 int vf
= LOOP_VINFO_VECT_FACTOR (loop_vinfo
);
3136 stmt_vec_info phi_info
= vinfo_for_stmt (iv_phi
);
3137 bool nested_in_vect_loop
= false;
3138 gimple_seq stmts
= NULL
;
3139 imm_use_iterator imm_iter
;
3140 use_operand_p use_p
;
3144 gimple_stmt_iterator si
;
3145 basic_block bb
= gimple_bb (iv_phi
);
3149 /* Is phi in an inner-loop, while vectorizing an enclosing outer-loop? */
3150 if (nested_in_vect_loop_p (loop
, iv_phi
))
3152 nested_in_vect_loop
= true;
3153 iv_loop
= loop
->inner
;
3157 gcc_assert (iv_loop
== (gimple_bb (iv_phi
))->loop_father
);
3159 latch_e
= loop_latch_edge (iv_loop
);
3160 loop_arg
= PHI_ARG_DEF_FROM_EDGE (iv_phi
, latch_e
);
3162 access_fn
= analyze_scalar_evolution (iv_loop
, PHI_RESULT (iv_phi
));
3163 gcc_assert (access_fn
);
3164 STRIP_NOPS (access_fn
);
3165 ok
= vect_is_simple_iv_evolution (iv_loop
->num
, access_fn
,
3166 &init_expr
, &step_expr
);
3168 pe
= loop_preheader_edge (iv_loop
);
3170 scalar_type
= TREE_TYPE (init_expr
);
3171 vectype
= get_vectype_for_scalar_type (scalar_type
);
3172 resvectype
= get_vectype_for_scalar_type (TREE_TYPE (PHI_RESULT (iv_phi
)));
3173 gcc_assert (vectype
);
3174 nunits
= TYPE_VECTOR_SUBPARTS (vectype
);
3175 ncopies
= vf
/ nunits
;
3177 gcc_assert (phi_info
);
3178 gcc_assert (ncopies
>= 1);
3180 /* Find the first insertion point in the BB. */
3181 si
= gsi_after_labels (bb
);
3183 /* Create the vector that holds the initial_value of the induction. */
3184 if (nested_in_vect_loop
)
3186 /* iv_loop is nested in the loop to be vectorized. init_expr had already
3187 been created during vectorization of previous stmts. We obtain it
3188 from the STMT_VINFO_VEC_STMT of the defining stmt. */
3189 tree iv_def
= PHI_ARG_DEF_FROM_EDGE (iv_phi
,
3190 loop_preheader_edge (iv_loop
));
3191 vec_init
= vect_get_vec_def_for_operand (iv_def
, iv_phi
, NULL
);
3192 /* If the initial value is not of proper type, convert it. */
3193 if (!useless_type_conversion_p (vectype
, TREE_TYPE (vec_init
)))
3195 new_stmt
= gimple_build_assign_with_ops
3197 vect_get_new_vect_var (vectype
, vect_simple_var
, "vec_iv_"),
3198 build1 (VIEW_CONVERT_EXPR
, vectype
, vec_init
), NULL_TREE
);
3199 vec_init
= make_ssa_name (gimple_assign_lhs (new_stmt
), new_stmt
);
3200 gimple_assign_set_lhs (new_stmt
, vec_init
);
3201 new_bb
= gsi_insert_on_edge_immediate (loop_preheader_edge (iv_loop
),
3203 gcc_assert (!new_bb
);
3204 set_vinfo_for_stmt (new_stmt
,
3205 new_stmt_vec_info (new_stmt
, loop_vinfo
, NULL
));
3210 vec
<constructor_elt
, va_gc
> *v
;
3212 /* iv_loop is the loop to be vectorized. Create:
3213 vec_init = [X, X+S, X+2*S, X+3*S] (S = step_expr, X = init_expr) */
3214 new_var
= vect_get_new_vect_var (scalar_type
, vect_scalar_var
, "var_");
3215 new_name
= force_gimple_operand (init_expr
, &stmts
, false, new_var
);
3218 new_bb
= gsi_insert_seq_on_edge_immediate (pe
, stmts
);
3219 gcc_assert (!new_bb
);
3222 vec_alloc (v
, nunits
);
3223 CONSTRUCTOR_APPEND_ELT (v
, NULL_TREE
, new_name
);
3224 for (i
= 1; i
< nunits
; i
++)
3226 /* Create: new_name_i = new_name + step_expr */
3227 enum tree_code code
= POINTER_TYPE_P (scalar_type
)
3228 ? POINTER_PLUS_EXPR
: PLUS_EXPR
;
3229 init_stmt
= gimple_build_assign_with_ops (code
, new_var
,
3230 new_name
, step_expr
);
3231 new_name
= make_ssa_name (new_var
, init_stmt
);
3232 gimple_assign_set_lhs (init_stmt
, new_name
);
3234 new_bb
= gsi_insert_on_edge_immediate (pe
, init_stmt
);
3235 gcc_assert (!new_bb
);
3237 if (dump_enabled_p ())
3239 dump_printf_loc (MSG_NOTE
, vect_location
,
3240 "created new init_stmt: ");
3241 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, init_stmt
, 0);
3243 CONSTRUCTOR_APPEND_ELT (v
, NULL_TREE
, new_name
);
3245 /* Create a vector from [new_name_0, new_name_1, ..., new_name_nunits-1] */
3246 new_vec
= build_constructor (vectype
, v
);
3247 vec_init
= vect_init_vector (iv_phi
, new_vec
, vectype
, NULL
);
3251 /* Create the vector that holds the step of the induction. */
3252 if (nested_in_vect_loop
)
3253 /* iv_loop is nested in the loop to be vectorized. Generate:
3254 vec_step = [S, S, S, S] */
3255 new_name
= step_expr
;
3258 /* iv_loop is the loop to be vectorized. Generate:
3259 vec_step = [VF*S, VF*S, VF*S, VF*S] */
3260 expr
= build_int_cst (TREE_TYPE (step_expr
), vf
);
3261 new_name
= fold_build2 (MULT_EXPR
, TREE_TYPE (step_expr
),
3265 t
= unshare_expr (new_name
);
3266 gcc_assert (CONSTANT_CLASS_P (new_name
));
3267 stepvectype
= get_vectype_for_scalar_type (TREE_TYPE (new_name
));
3268 gcc_assert (stepvectype
);
3269 new_vec
= build_vector_from_val (stepvectype
, t
);
3270 vec_step
= vect_init_vector (iv_phi
, new_vec
, stepvectype
, NULL
);
3273 /* Create the following def-use cycle:
3278 vec_iv = PHI <vec_init, vec_loop>
3282 vec_loop = vec_iv + vec_step; */
3284 /* Create the induction-phi that defines the induction-operand. */
3285 vec_dest
= vect_get_new_vect_var (vectype
, vect_simple_var
, "vec_iv_");
3286 induction_phi
= create_phi_node (vec_dest
, iv_loop
->header
);
3287 set_vinfo_for_stmt (induction_phi
,
3288 new_stmt_vec_info (induction_phi
, loop_vinfo
, NULL
));
3289 induc_def
= PHI_RESULT (induction_phi
);
3291 /* Create the iv update inside the loop */
3292 new_stmt
= gimple_build_assign_with_ops (PLUS_EXPR
, vec_dest
,
3293 induc_def
, vec_step
);
3294 vec_def
= make_ssa_name (vec_dest
, new_stmt
);
3295 gimple_assign_set_lhs (new_stmt
, vec_def
);
3296 gsi_insert_before (&si
, new_stmt
, GSI_SAME_STMT
);
3297 set_vinfo_for_stmt (new_stmt
, new_stmt_vec_info (new_stmt
, loop_vinfo
,
3300 /* Set the arguments of the phi node: */
3301 add_phi_arg (induction_phi
, vec_init
, pe
, UNKNOWN_LOCATION
);
3302 add_phi_arg (induction_phi
, vec_def
, loop_latch_edge (iv_loop
),
3306 /* In case that vectorization factor (VF) is bigger than the number
3307 of elements that we can fit in a vectype (nunits), we have to generate
3308 more than one vector stmt - i.e - we need to "unroll" the
3309 vector stmt by a factor VF/nunits. For more details see documentation
3310 in vectorizable_operation. */
3314 stmt_vec_info prev_stmt_vinfo
;
3315 /* FORNOW. This restriction should be relaxed. */
3316 gcc_assert (!nested_in_vect_loop
);
3318 /* Create the vector that holds the step of the induction. */
3319 expr
= build_int_cst (TREE_TYPE (step_expr
), nunits
);
3320 new_name
= fold_build2 (MULT_EXPR
, TREE_TYPE (step_expr
),
3322 t
= unshare_expr (new_name
);
3323 gcc_assert (CONSTANT_CLASS_P (new_name
));
3324 new_vec
= build_vector_from_val (stepvectype
, t
);
3325 vec_step
= vect_init_vector (iv_phi
, new_vec
, stepvectype
, NULL
);
3327 vec_def
= induc_def
;
3328 prev_stmt_vinfo
= vinfo_for_stmt (induction_phi
);
3329 for (i
= 1; i
< ncopies
; i
++)
3331 /* vec_i = vec_prev + vec_step */
3332 new_stmt
= gimple_build_assign_with_ops (PLUS_EXPR
, vec_dest
,
3334 vec_def
= make_ssa_name (vec_dest
, new_stmt
);
3335 gimple_assign_set_lhs (new_stmt
, vec_def
);
3337 gsi_insert_before (&si
, new_stmt
, GSI_SAME_STMT
);
3338 if (!useless_type_conversion_p (resvectype
, vectype
))
3340 new_stmt
= gimple_build_assign_with_ops
3342 vect_get_new_vect_var (resvectype
, vect_simple_var
,
3344 build1 (VIEW_CONVERT_EXPR
, resvectype
,
3345 gimple_assign_lhs (new_stmt
)), NULL_TREE
);
3346 gimple_assign_set_lhs (new_stmt
,
3348 (gimple_assign_lhs (new_stmt
), new_stmt
));
3349 gsi_insert_before (&si
, new_stmt
, GSI_SAME_STMT
);
3351 set_vinfo_for_stmt (new_stmt
,
3352 new_stmt_vec_info (new_stmt
, loop_vinfo
, NULL
));
3353 STMT_VINFO_RELATED_STMT (prev_stmt_vinfo
) = new_stmt
;
3354 prev_stmt_vinfo
= vinfo_for_stmt (new_stmt
);
3358 if (nested_in_vect_loop
)
3360 /* Find the loop-closed exit-phi of the induction, and record
3361 the final vector of induction results: */
3363 FOR_EACH_IMM_USE_FAST (use_p
, imm_iter
, loop_arg
)
3365 if (!flow_bb_inside_loop_p (iv_loop
, gimple_bb (USE_STMT (use_p
))))
3367 exit_phi
= USE_STMT (use_p
);
3373 stmt_vec_info stmt_vinfo
= vinfo_for_stmt (exit_phi
);
3374 /* FORNOW. Currently not supporting the case that an inner-loop induction
3375 is not used in the outer-loop (i.e. only outside the outer-loop). */
3376 gcc_assert (STMT_VINFO_RELEVANT_P (stmt_vinfo
)
3377 && !STMT_VINFO_LIVE_P (stmt_vinfo
));
3379 STMT_VINFO_VEC_STMT (stmt_vinfo
) = new_stmt
;
3380 if (dump_enabled_p ())
3382 dump_printf_loc (MSG_NOTE
, vect_location
,
3383 "vector of inductions after inner-loop:");
3384 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, new_stmt
, 0);
3390 if (dump_enabled_p ())
3392 dump_printf_loc (MSG_NOTE
, vect_location
,
3393 "transform induction: created def-use cycle: ");
3394 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, induction_phi
, 0);
3395 dump_printf (MSG_NOTE
, "\n");
3396 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
,
3397 SSA_NAME_DEF_STMT (vec_def
), 0);
3400 STMT_VINFO_VEC_STMT (phi_info
) = induction_phi
;
3401 if (!useless_type_conversion_p (resvectype
, vectype
))
3403 new_stmt
= gimple_build_assign_with_ops
3405 vect_get_new_vect_var (resvectype
, vect_simple_var
, "vec_iv_"),
3406 build1 (VIEW_CONVERT_EXPR
, resvectype
, induc_def
), NULL_TREE
);
3407 induc_def
= make_ssa_name (gimple_assign_lhs (new_stmt
), new_stmt
);
3408 gimple_assign_set_lhs (new_stmt
, induc_def
);
3409 si
= gsi_after_labels (bb
);
3410 gsi_insert_before (&si
, new_stmt
, GSI_SAME_STMT
);
3411 set_vinfo_for_stmt (new_stmt
,
3412 new_stmt_vec_info (new_stmt
, loop_vinfo
, NULL
));
3413 STMT_VINFO_RELATED_STMT (vinfo_for_stmt (new_stmt
))
3414 = STMT_VINFO_RELATED_STMT (vinfo_for_stmt (induction_phi
));
3421 /* Function get_initial_def_for_reduction
3424 STMT - a stmt that performs a reduction operation in the loop.
3425 INIT_VAL - the initial value of the reduction variable
3428 ADJUSTMENT_DEF - a tree that holds a value to be added to the final result
3429 of the reduction (used for adjusting the epilog - see below).
3430 Return a vector variable, initialized according to the operation that STMT
3431 performs. This vector will be used as the initial value of the
3432 vector of partial results.
3434 Option1 (adjust in epilog): Initialize the vector as follows:
3435 add/bit or/xor: [0,0,...,0,0]
3436 mult/bit and: [1,1,...,1,1]
3437 min/max/cond_expr: [init_val,init_val,..,init_val,init_val]
3438 and when necessary (e.g. add/mult case) let the caller know
3439 that it needs to adjust the result by init_val.
3441 Option2: Initialize the vector as follows:
3442 add/bit or/xor: [init_val,0,0,...,0]
3443 mult/bit and: [init_val,1,1,...,1]
3444 min/max/cond_expr: [init_val,init_val,...,init_val]
3445 and no adjustments are needed.
3447 For example, for the following code:
3453 STMT is 's = s + a[i]', and the reduction variable is 's'.
3454 For a vector of 4 units, we want to return either [0,0,0,init_val],
3455 or [0,0,0,0] and let the caller know that it needs to adjust
3456 the result at the end by 'init_val'.
3458 FORNOW, we are using the 'adjust in epilog' scheme, because this way the
3459 initialization vector is simpler (same element in all entries), if
3460 ADJUSTMENT_DEF is not NULL, and Option2 otherwise.
3462 A cost model should help decide between these two schemes. */
3465 get_initial_def_for_reduction (gimple stmt
, tree init_val
,
3466 tree
*adjustment_def
)
3468 stmt_vec_info stmt_vinfo
= vinfo_for_stmt (stmt
);
3469 loop_vec_info loop_vinfo
= STMT_VINFO_LOOP_VINFO (stmt_vinfo
);
3470 struct loop
*loop
= LOOP_VINFO_LOOP (loop_vinfo
);
3471 tree scalar_type
= TREE_TYPE (init_val
);
3472 tree vectype
= get_vectype_for_scalar_type (scalar_type
);
3474 enum tree_code code
= gimple_assign_rhs_code (stmt
);
3479 bool nested_in_vect_loop
= false;
3481 REAL_VALUE_TYPE real_init_val
= dconst0
;
3482 int int_init_val
= 0;
3483 gimple def_stmt
= NULL
;
3485 gcc_assert (vectype
);
3486 nunits
= TYPE_VECTOR_SUBPARTS (vectype
);
3488 gcc_assert (POINTER_TYPE_P (scalar_type
) || INTEGRAL_TYPE_P (scalar_type
)
3489 || SCALAR_FLOAT_TYPE_P (scalar_type
));
3491 if (nested_in_vect_loop_p (loop
, stmt
))
3492 nested_in_vect_loop
= true;
3494 gcc_assert (loop
== (gimple_bb (stmt
))->loop_father
);
3496 /* In case of double reduction we only create a vector variable to be put
3497 in the reduction phi node. The actual statement creation is done in
3498 vect_create_epilog_for_reduction. */
3499 if (adjustment_def
&& nested_in_vect_loop
3500 && TREE_CODE (init_val
) == SSA_NAME
3501 && (def_stmt
= SSA_NAME_DEF_STMT (init_val
))
3502 && gimple_code (def_stmt
) == GIMPLE_PHI
3503 && flow_bb_inside_loop_p (loop
, gimple_bb (def_stmt
))
3504 && vinfo_for_stmt (def_stmt
)
3505 && STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def_stmt
))
3506 == vect_double_reduction_def
)
3508 *adjustment_def
= NULL
;
3509 return vect_create_destination_var (init_val
, vectype
);
3512 if (TREE_CONSTANT (init_val
))
3514 if (SCALAR_FLOAT_TYPE_P (scalar_type
))
3515 init_value
= build_real (scalar_type
, TREE_REAL_CST (init_val
));
3517 init_value
= build_int_cst (scalar_type
, TREE_INT_CST_LOW (init_val
));
3520 init_value
= init_val
;
3524 case WIDEN_SUM_EXPR
:
3532 /* ADJUSMENT_DEF is NULL when called from
3533 vect_create_epilog_for_reduction to vectorize double reduction. */
3536 if (nested_in_vect_loop
)
3537 *adjustment_def
= vect_get_vec_def_for_operand (init_val
, stmt
,
3540 *adjustment_def
= init_val
;
3543 if (code
== MULT_EXPR
)
3545 real_init_val
= dconst1
;
3549 if (code
== BIT_AND_EXPR
)
3552 if (SCALAR_FLOAT_TYPE_P (scalar_type
))
3553 def_for_init
= build_real (scalar_type
, real_init_val
);
3555 def_for_init
= build_int_cst (scalar_type
, int_init_val
);
3557 /* Create a vector of '0' or '1' except the first element. */
3558 elts
= XALLOCAVEC (tree
, nunits
);
3559 for (i
= nunits
- 2; i
>= 0; --i
)
3560 elts
[i
+ 1] = def_for_init
;
3562 /* Option1: the first element is '0' or '1' as well. */
3565 elts
[0] = def_for_init
;
3566 init_def
= build_vector (vectype
, elts
);
3570 /* Option2: the first element is INIT_VAL. */
3572 if (TREE_CONSTANT (init_val
))
3573 init_def
= build_vector (vectype
, elts
);
3576 vec
<constructor_elt
, va_gc
> *v
;
3577 vec_alloc (v
, nunits
);
3578 CONSTRUCTOR_APPEND_ELT (v
, NULL_TREE
, init_val
);
3579 for (i
= 1; i
< nunits
; ++i
)
3580 CONSTRUCTOR_APPEND_ELT (v
, NULL_TREE
, elts
[i
]);
3581 init_def
= build_constructor (vectype
, v
);
3591 *adjustment_def
= NULL_TREE
;
3592 init_def
= vect_get_vec_def_for_operand (init_val
, stmt
, NULL
);
3596 init_def
= build_vector_from_val (vectype
, init_value
);
3607 /* Function vect_create_epilog_for_reduction
3609 Create code at the loop-epilog to finalize the result of a reduction
3612 VECT_DEFS is list of vector of partial results, i.e., the lhs's of vector
3613 reduction statements.
3614 STMT is the scalar reduction stmt that is being vectorized.
3615 NCOPIES is > 1 in case the vectorization factor (VF) is bigger than the
3616 number of elements that we can fit in a vectype (nunits). In this case
3617 we have to generate more than one vector stmt - i.e - we need to "unroll"
3618 the vector stmt by a factor VF/nunits. For more details see documentation
3619 in vectorizable_operation.
3620 REDUC_CODE is the tree-code for the epilog reduction.
3621 REDUCTION_PHIS is a list of the phi-nodes that carry the reduction
3623 REDUC_INDEX is the index of the operand in the right hand side of the
3624 statement that is defined by REDUCTION_PHI.
3625 DOUBLE_REDUC is TRUE if double reduction phi nodes should be handled.
3626 SLP_NODE is an SLP node containing a group of reduction statements. The
3627 first one in this group is STMT.
3630 1. Creates the reduction def-use cycles: sets the arguments for
3632 The loop-entry argument is the vectorized initial-value of the reduction.
3633 The loop-latch argument is taken from VECT_DEFS - the vector of partial
3635 2. "Reduces" each vector of partial results VECT_DEFS into a single result,
3636 by applying the operation specified by REDUC_CODE if available, or by
3637 other means (whole-vector shifts or a scalar loop).
3638 The function also creates a new phi node at the loop exit to preserve
3639 loop-closed form, as illustrated below.
3641 The flow at the entry to this function:
3644 vec_def = phi <null, null> # REDUCTION_PHI
3645 VECT_DEF = vector_stmt # vectorized form of STMT
3646 s_loop = scalar_stmt # (scalar) STMT
3648 s_out0 = phi <s_loop> # (scalar) EXIT_PHI
3652 The above is transformed by this function into:
3655 vec_def = phi <vec_init, VECT_DEF> # REDUCTION_PHI
3656 VECT_DEF = vector_stmt # vectorized form of STMT
3657 s_loop = scalar_stmt # (scalar) STMT
3659 s_out0 = phi <s_loop> # (scalar) EXIT_PHI
3660 v_out1 = phi <VECT_DEF> # NEW_EXIT_PHI
3661 v_out2 = reduce <v_out1>
3662 s_out3 = extract_field <v_out2, 0>
3663 s_out4 = adjust_result <s_out3>
3669 vect_create_epilog_for_reduction (vec
<tree
> vect_defs
, gimple stmt
,
3670 int ncopies
, enum tree_code reduc_code
,
3671 vec
<gimple
> reduction_phis
,
3672 int reduc_index
, bool double_reduc
,
3675 stmt_vec_info stmt_info
= vinfo_for_stmt (stmt
);
3676 stmt_vec_info prev_phi_info
;
3678 enum machine_mode mode
;
3679 loop_vec_info loop_vinfo
= STMT_VINFO_LOOP_VINFO (stmt_info
);
3680 struct loop
*loop
= LOOP_VINFO_LOOP (loop_vinfo
), *outer_loop
= NULL
;
3681 basic_block exit_bb
;
3684 gimple new_phi
= NULL
, phi
;
3685 gimple_stmt_iterator exit_gsi
;
3687 tree new_temp
= NULL_TREE
, new_dest
, new_name
, new_scalar_dest
;
3688 gimple epilog_stmt
= NULL
;
3689 enum tree_code code
= gimple_assign_rhs_code (stmt
);
3691 tree bitsize
, bitpos
;
3692 tree adjustment_def
= NULL
;
3693 tree vec_initial_def
= NULL
;
3694 tree reduction_op
, expr
, def
;
3695 tree orig_name
, scalar_result
;
3696 imm_use_iterator imm_iter
, phi_imm_iter
;
3697 use_operand_p use_p
, phi_use_p
;
3698 bool extract_scalar_result
= false;
3699 gimple use_stmt
, orig_stmt
, reduction_phi
= NULL
;
3700 bool nested_in_vect_loop
= false;
3701 vec
<gimple
> new_phis
= vNULL
;
3702 vec
<gimple
> inner_phis
= vNULL
;
3703 enum vect_def_type dt
= vect_unknown_def_type
;
3705 vec
<tree
> scalar_results
= vNULL
;
3706 unsigned int group_size
= 1, k
, ratio
;
3707 vec
<tree
> vec_initial_defs
= vNULL
;
3709 bool slp_reduc
= false;
3710 tree new_phi_result
;
3711 gimple inner_phi
= NULL
;
3714 group_size
= SLP_TREE_SCALAR_STMTS (slp_node
).length ();
3716 if (nested_in_vect_loop_p (loop
, stmt
))
3720 nested_in_vect_loop
= true;
3721 gcc_assert (!slp_node
);
3724 switch (get_gimple_rhs_class (gimple_assign_rhs_code (stmt
)))
3726 case GIMPLE_SINGLE_RHS
:
3727 gcc_assert (TREE_OPERAND_LENGTH (gimple_assign_rhs1 (stmt
))
3729 reduction_op
= TREE_OPERAND (gimple_assign_rhs1 (stmt
), reduc_index
);
3731 case GIMPLE_UNARY_RHS
:
3732 reduction_op
= gimple_assign_rhs1 (stmt
);
3734 case GIMPLE_BINARY_RHS
:
3735 reduction_op
= reduc_index
?
3736 gimple_assign_rhs2 (stmt
) : gimple_assign_rhs1 (stmt
);
3738 case GIMPLE_TERNARY_RHS
:
3739 reduction_op
= gimple_op (stmt
, reduc_index
+ 1);
3745 vectype
= get_vectype_for_scalar_type (TREE_TYPE (reduction_op
));
3746 gcc_assert (vectype
);
3747 mode
= TYPE_MODE (vectype
);
3749 /* 1. Create the reduction def-use cycle:
3750 Set the arguments of REDUCTION_PHIS, i.e., transform
3753 vec_def = phi <null, null> # REDUCTION_PHI
3754 VECT_DEF = vector_stmt # vectorized form of STMT
3760 vec_def = phi <vec_init, VECT_DEF> # REDUCTION_PHI
3761 VECT_DEF = vector_stmt # vectorized form of STMT
3764 (in case of SLP, do it for all the phis). */
3766 /* Get the loop-entry arguments. */
3768 vect_get_vec_defs (reduction_op
, NULL_TREE
, stmt
, &vec_initial_defs
,
3769 NULL
, slp_node
, reduc_index
);
3772 vec_initial_defs
.create (1);
3773 /* For the case of reduction, vect_get_vec_def_for_operand returns
3774 the scalar def before the loop, that defines the initial value
3775 of the reduction variable. */
3776 vec_initial_def
= vect_get_vec_def_for_operand (reduction_op
, stmt
,
3778 vec_initial_defs
.quick_push (vec_initial_def
);
3781 /* Set phi nodes arguments. */
3782 FOR_EACH_VEC_ELT (reduction_phis
, i
, phi
)
3784 tree vec_init_def
= vec_initial_defs
[i
];
3785 tree def
= vect_defs
[i
];
3786 for (j
= 0; j
< ncopies
; j
++)
3788 /* Set the loop-entry arg of the reduction-phi. */
3789 add_phi_arg (phi
, vec_init_def
, loop_preheader_edge (loop
),
3792 /* Set the loop-latch arg for the reduction-phi. */
3794 def
= vect_get_vec_def_for_stmt_copy (vect_unknown_def_type
, def
);
3796 add_phi_arg (phi
, def
, loop_latch_edge (loop
), UNKNOWN_LOCATION
);
3798 if (dump_enabled_p ())
3800 dump_printf_loc (MSG_NOTE
, vect_location
,
3801 "transform reduction: created def-use cycle: ");
3802 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, phi
, 0);
3803 dump_printf (MSG_NOTE
, "\n");
3804 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, SSA_NAME_DEF_STMT (def
), 0);
3807 phi
= STMT_VINFO_RELATED_STMT (vinfo_for_stmt (phi
));
3811 vec_initial_defs
.release ();
3813 /* 2. Create epilog code.
3814 The reduction epilog code operates across the elements of the vector
3815 of partial results computed by the vectorized loop.
3816 The reduction epilog code consists of:
3818 step 1: compute the scalar result in a vector (v_out2)
3819 step 2: extract the scalar result (s_out3) from the vector (v_out2)
3820 step 3: adjust the scalar result (s_out3) if needed.
3822 Step 1 can be accomplished using one the following three schemes:
3823 (scheme 1) using reduc_code, if available.
3824 (scheme 2) using whole-vector shifts, if available.
3825 (scheme 3) using a scalar loop. In this case steps 1+2 above are
3828 The overall epilog code looks like this:
3830 s_out0 = phi <s_loop> # original EXIT_PHI
3831 v_out1 = phi <VECT_DEF> # NEW_EXIT_PHI
3832 v_out2 = reduce <v_out1> # step 1
3833 s_out3 = extract_field <v_out2, 0> # step 2
3834 s_out4 = adjust_result <s_out3> # step 3
3836 (step 3 is optional, and steps 1 and 2 may be combined).
3837 Lastly, the uses of s_out0 are replaced by s_out4. */
3840 /* 2.1 Create new loop-exit-phis to preserve loop-closed form:
3841 v_out1 = phi <VECT_DEF>
3842 Store them in NEW_PHIS. */
3844 exit_bb
= single_exit (loop
)->dest
;
3845 prev_phi_info
= NULL
;
3846 new_phis
.create (vect_defs
.length ());
3847 FOR_EACH_VEC_ELT (vect_defs
, i
, def
)
3849 for (j
= 0; j
< ncopies
; j
++)
3851 tree new_def
= copy_ssa_name (def
, NULL
);
3852 phi
= create_phi_node (new_def
, exit_bb
);
3853 set_vinfo_for_stmt (phi
, new_stmt_vec_info (phi
, loop_vinfo
, NULL
));
3855 new_phis
.quick_push (phi
);
3858 def
= vect_get_vec_def_for_stmt_copy (dt
, def
);
3859 STMT_VINFO_RELATED_STMT (prev_phi_info
) = phi
;
3862 SET_PHI_ARG_DEF (phi
, single_exit (loop
)->dest_idx
, def
);
3863 prev_phi_info
= vinfo_for_stmt (phi
);
3867 /* The epilogue is created for the outer-loop, i.e., for the loop being
3868 vectorized. Create exit phis for the outer loop. */
3872 exit_bb
= single_exit (loop
)->dest
;
3873 inner_phis
.create (vect_defs
.length ());
3874 FOR_EACH_VEC_ELT (new_phis
, i
, phi
)
3876 tree new_result
= copy_ssa_name (PHI_RESULT (phi
), NULL
);
3877 gimple outer_phi
= create_phi_node (new_result
, exit_bb
);
3878 SET_PHI_ARG_DEF (outer_phi
, single_exit (loop
)->dest_idx
,
3880 set_vinfo_for_stmt (outer_phi
, new_stmt_vec_info (outer_phi
,
3882 inner_phis
.quick_push (phi
);
3883 new_phis
[i
] = outer_phi
;
3884 prev_phi_info
= vinfo_for_stmt (outer_phi
);
3885 while (STMT_VINFO_RELATED_STMT (vinfo_for_stmt (phi
)))
3887 phi
= STMT_VINFO_RELATED_STMT (vinfo_for_stmt (phi
));
3888 new_result
= copy_ssa_name (PHI_RESULT (phi
), NULL
);
3889 outer_phi
= create_phi_node (new_result
, exit_bb
);
3890 SET_PHI_ARG_DEF (outer_phi
, single_exit (loop
)->dest_idx
,
3892 set_vinfo_for_stmt (outer_phi
, new_stmt_vec_info (outer_phi
,
3894 STMT_VINFO_RELATED_STMT (prev_phi_info
) = outer_phi
;
3895 prev_phi_info
= vinfo_for_stmt (outer_phi
);
3900 exit_gsi
= gsi_after_labels (exit_bb
);
3902 /* 2.2 Get the relevant tree-code to use in the epilog for schemes 2,3
3903 (i.e. when reduc_code is not available) and in the final adjustment
3904 code (if needed). Also get the original scalar reduction variable as
3905 defined in the loop. In case STMT is a "pattern-stmt" (i.e. - it
3906 represents a reduction pattern), the tree-code and scalar-def are
3907 taken from the original stmt that the pattern-stmt (STMT) replaces.
3908 Otherwise (it is a regular reduction) - the tree-code and scalar-def
3909 are taken from STMT. */
3911 orig_stmt
= STMT_VINFO_RELATED_STMT (stmt_info
);
3914 /* Regular reduction */
3919 /* Reduction pattern */
3920 stmt_vec_info stmt_vinfo
= vinfo_for_stmt (orig_stmt
);
3921 gcc_assert (STMT_VINFO_IN_PATTERN_P (stmt_vinfo
));
3922 gcc_assert (STMT_VINFO_RELATED_STMT (stmt_vinfo
) == stmt
);
3925 code
= gimple_assign_rhs_code (orig_stmt
);
3926 /* For MINUS_EXPR the initial vector is [init_val,0,...,0], therefore,
3927 partial results are added and not subtracted. */
3928 if (code
== MINUS_EXPR
)
3931 scalar_dest
= gimple_assign_lhs (orig_stmt
);
3932 scalar_type
= TREE_TYPE (scalar_dest
);
3933 scalar_results
.create (group_size
);
3934 new_scalar_dest
= vect_create_destination_var (scalar_dest
, NULL
);
3935 bitsize
= TYPE_SIZE (scalar_type
);
3937 /* In case this is a reduction in an inner-loop while vectorizing an outer
3938 loop - we don't need to extract a single scalar result at the end of the
3939 inner-loop (unless it is double reduction, i.e., the use of reduction is
3940 outside the outer-loop). The final vector of partial results will be used
3941 in the vectorized outer-loop, or reduced to a scalar result at the end of
3943 if (nested_in_vect_loop
&& !double_reduc
)
3944 goto vect_finalize_reduction
;
3946 /* SLP reduction without reduction chain, e.g.,
3950 b2 = operation (b1) */
3951 slp_reduc
= (slp_node
&& !GROUP_FIRST_ELEMENT (vinfo_for_stmt (stmt
)));
3953 /* In case of reduction chain, e.g.,
3956 a3 = operation (a2),
3958 we may end up with more than one vector result. Here we reduce them to
3960 if (GROUP_FIRST_ELEMENT (vinfo_for_stmt (stmt
)))
3962 tree first_vect
= PHI_RESULT (new_phis
[0]);
3964 gimple new_vec_stmt
= NULL
;
3966 vec_dest
= vect_create_destination_var (scalar_dest
, vectype
);
3967 for (k
= 1; k
< new_phis
.length (); k
++)
3969 gimple next_phi
= new_phis
[k
];
3970 tree second_vect
= PHI_RESULT (next_phi
);
3972 tmp
= build2 (code
, vectype
, first_vect
, second_vect
);
3973 new_vec_stmt
= gimple_build_assign (vec_dest
, tmp
);
3974 first_vect
= make_ssa_name (vec_dest
, new_vec_stmt
);
3975 gimple_assign_set_lhs (new_vec_stmt
, first_vect
);
3976 gsi_insert_before (&exit_gsi
, new_vec_stmt
, GSI_SAME_STMT
);
3979 new_phi_result
= first_vect
;
3982 new_phis
.truncate (0);
3983 new_phis
.safe_push (new_vec_stmt
);
3987 new_phi_result
= PHI_RESULT (new_phis
[0]);
3989 /* 2.3 Create the reduction code, using one of the three schemes described
3990 above. In SLP we simply need to extract all the elements from the
3991 vector (without reducing them), so we use scalar shifts. */
3992 if (reduc_code
!= ERROR_MARK
&& !slp_reduc
)
3996 /*** Case 1: Create:
3997 v_out2 = reduc_expr <v_out1> */
3999 if (dump_enabled_p ())
4000 dump_printf_loc (MSG_NOTE
, vect_location
,
4001 "Reduce using direct vector reduction.");
4003 vec_dest
= vect_create_destination_var (scalar_dest
, vectype
);
4004 tmp
= build1 (reduc_code
, vectype
, new_phi_result
);
4005 epilog_stmt
= gimple_build_assign (vec_dest
, tmp
);
4006 new_temp
= make_ssa_name (vec_dest
, epilog_stmt
);
4007 gimple_assign_set_lhs (epilog_stmt
, new_temp
);
4008 gsi_insert_before (&exit_gsi
, epilog_stmt
, GSI_SAME_STMT
);
4010 extract_scalar_result
= true;
4014 enum tree_code shift_code
= ERROR_MARK
;
4015 bool have_whole_vector_shift
= true;
4017 int element_bitsize
= tree_low_cst (bitsize
, 1);
4018 int vec_size_in_bits
= tree_low_cst (TYPE_SIZE (vectype
), 1);
4021 if (optab_handler (vec_shr_optab
, mode
) != CODE_FOR_nothing
)
4022 shift_code
= VEC_RSHIFT_EXPR
;
4024 have_whole_vector_shift
= false;
4026 /* Regardless of whether we have a whole vector shift, if we're
4027 emulating the operation via tree-vect-generic, we don't want
4028 to use it. Only the first round of the reduction is likely
4029 to still be profitable via emulation. */
4030 /* ??? It might be better to emit a reduction tree code here, so that
4031 tree-vect-generic can expand the first round via bit tricks. */
4032 if (!VECTOR_MODE_P (mode
))
4033 have_whole_vector_shift
= false;
4036 optab optab
= optab_for_tree_code (code
, vectype
, optab_default
);
4037 if (optab_handler (optab
, mode
) == CODE_FOR_nothing
)
4038 have_whole_vector_shift
= false;
4041 if (have_whole_vector_shift
&& !slp_reduc
)
4043 /*** Case 2: Create:
4044 for (offset = VS/2; offset >= element_size; offset/=2)
4046 Create: va' = vec_shift <va, offset>
4047 Create: va = vop <va, va'>
4050 if (dump_enabled_p ())
4051 dump_printf_loc (MSG_NOTE
, vect_location
,
4052 "Reduce using vector shifts");
4054 vec_dest
= vect_create_destination_var (scalar_dest
, vectype
);
4055 new_temp
= new_phi_result
;
4056 for (bit_offset
= vec_size_in_bits
/2;
4057 bit_offset
>= element_bitsize
;
4060 tree bitpos
= size_int (bit_offset
);
4062 epilog_stmt
= gimple_build_assign_with_ops (shift_code
,
4063 vec_dest
, new_temp
, bitpos
);
4064 new_name
= make_ssa_name (vec_dest
, epilog_stmt
);
4065 gimple_assign_set_lhs (epilog_stmt
, new_name
);
4066 gsi_insert_before (&exit_gsi
, epilog_stmt
, GSI_SAME_STMT
);
4068 epilog_stmt
= gimple_build_assign_with_ops (code
, vec_dest
,
4069 new_name
, new_temp
);
4070 new_temp
= make_ssa_name (vec_dest
, epilog_stmt
);
4071 gimple_assign_set_lhs (epilog_stmt
, new_temp
);
4072 gsi_insert_before (&exit_gsi
, epilog_stmt
, GSI_SAME_STMT
);
4075 extract_scalar_result
= true;
4081 /*** Case 3: Create:
4082 s = extract_field <v_out2, 0>
4083 for (offset = element_size;
4084 offset < vector_size;
4085 offset += element_size;)
4087 Create: s' = extract_field <v_out2, offset>
4088 Create: s = op <s, s'> // For non SLP cases
4091 if (dump_enabled_p ())
4092 dump_printf_loc (MSG_NOTE
, vect_location
,
4093 "Reduce using scalar code. ");
4095 vec_size_in_bits
= tree_low_cst (TYPE_SIZE (vectype
), 1);
4096 FOR_EACH_VEC_ELT (new_phis
, i
, new_phi
)
4098 if (gimple_code (new_phi
) == GIMPLE_PHI
)
4099 vec_temp
= PHI_RESULT (new_phi
);
4101 vec_temp
= gimple_assign_lhs (new_phi
);
4102 rhs
= build3 (BIT_FIELD_REF
, scalar_type
, vec_temp
, bitsize
,
4104 epilog_stmt
= gimple_build_assign (new_scalar_dest
, rhs
);
4105 new_temp
= make_ssa_name (new_scalar_dest
, epilog_stmt
);
4106 gimple_assign_set_lhs (epilog_stmt
, new_temp
);
4107 gsi_insert_before (&exit_gsi
, epilog_stmt
, GSI_SAME_STMT
);
4109 /* In SLP we don't need to apply reduction operation, so we just
4110 collect s' values in SCALAR_RESULTS. */
4112 scalar_results
.safe_push (new_temp
);
4114 for (bit_offset
= element_bitsize
;
4115 bit_offset
< vec_size_in_bits
;
4116 bit_offset
+= element_bitsize
)
4118 tree bitpos
= bitsize_int (bit_offset
);
4119 tree rhs
= build3 (BIT_FIELD_REF
, scalar_type
, vec_temp
,
4122 epilog_stmt
= gimple_build_assign (new_scalar_dest
, rhs
);
4123 new_name
= make_ssa_name (new_scalar_dest
, epilog_stmt
);
4124 gimple_assign_set_lhs (epilog_stmt
, new_name
);
4125 gsi_insert_before (&exit_gsi
, epilog_stmt
, GSI_SAME_STMT
);
4129 /* In SLP we don't need to apply reduction operation, so
4130 we just collect s' values in SCALAR_RESULTS. */
4131 new_temp
= new_name
;
4132 scalar_results
.safe_push (new_name
);
4136 epilog_stmt
= gimple_build_assign_with_ops (code
,
4137 new_scalar_dest
, new_name
, new_temp
);
4138 new_temp
= make_ssa_name (new_scalar_dest
, epilog_stmt
);
4139 gimple_assign_set_lhs (epilog_stmt
, new_temp
);
4140 gsi_insert_before (&exit_gsi
, epilog_stmt
, GSI_SAME_STMT
);
4145 /* The only case where we need to reduce scalar results in SLP, is
4146 unrolling. If the size of SCALAR_RESULTS is greater than
4147 GROUP_SIZE, we reduce them combining elements modulo
4151 tree res
, first_res
, new_res
;
4154 /* Reduce multiple scalar results in case of SLP unrolling. */
4155 for (j
= group_size
; scalar_results
.iterate (j
, &res
);
4158 first_res
= scalar_results
[j
% group_size
];
4159 new_stmt
= gimple_build_assign_with_ops (code
,
4160 new_scalar_dest
, first_res
, res
);
4161 new_res
= make_ssa_name (new_scalar_dest
, new_stmt
);
4162 gimple_assign_set_lhs (new_stmt
, new_res
);
4163 gsi_insert_before (&exit_gsi
, new_stmt
, GSI_SAME_STMT
);
4164 scalar_results
[j
% group_size
] = new_res
;
4168 /* Not SLP - we have one scalar to keep in SCALAR_RESULTS. */
4169 scalar_results
.safe_push (new_temp
);
4171 extract_scalar_result
= false;
4175 /* 2.4 Extract the final scalar result. Create:
4176 s_out3 = extract_field <v_out2, bitpos> */
4178 if (extract_scalar_result
)
4182 if (dump_enabled_p ())
4183 dump_printf_loc (MSG_NOTE
, vect_location
,
4184 "extract scalar result");
4186 if (BYTES_BIG_ENDIAN
)
4187 bitpos
= size_binop (MULT_EXPR
,
4188 bitsize_int (TYPE_VECTOR_SUBPARTS (vectype
) - 1),
4189 TYPE_SIZE (scalar_type
));
4191 bitpos
= bitsize_zero_node
;
4193 rhs
= build3 (BIT_FIELD_REF
, scalar_type
, new_temp
, bitsize
, bitpos
);
4194 epilog_stmt
= gimple_build_assign (new_scalar_dest
, rhs
);
4195 new_temp
= make_ssa_name (new_scalar_dest
, epilog_stmt
);
4196 gimple_assign_set_lhs (epilog_stmt
, new_temp
);
4197 gsi_insert_before (&exit_gsi
, epilog_stmt
, GSI_SAME_STMT
);
4198 scalar_results
.safe_push (new_temp
);
4201 vect_finalize_reduction
:
4206 /* 2.5 Adjust the final result by the initial value of the reduction
4207 variable. (When such adjustment is not needed, then
4208 'adjustment_def' is zero). For example, if code is PLUS we create:
4209 new_temp = loop_exit_def + adjustment_def */
4213 gcc_assert (!slp_reduc
);
4214 if (nested_in_vect_loop
)
4216 new_phi
= new_phis
[0];
4217 gcc_assert (TREE_CODE (TREE_TYPE (adjustment_def
)) == VECTOR_TYPE
);
4218 expr
= build2 (code
, vectype
, PHI_RESULT (new_phi
), adjustment_def
);
4219 new_dest
= vect_create_destination_var (scalar_dest
, vectype
);
4223 new_temp
= scalar_results
[0];
4224 gcc_assert (TREE_CODE (TREE_TYPE (adjustment_def
)) != VECTOR_TYPE
);
4225 expr
= build2 (code
, scalar_type
, new_temp
, adjustment_def
);
4226 new_dest
= vect_create_destination_var (scalar_dest
, scalar_type
);
4229 epilog_stmt
= gimple_build_assign (new_dest
, expr
);
4230 new_temp
= make_ssa_name (new_dest
, epilog_stmt
);
4231 gimple_assign_set_lhs (epilog_stmt
, new_temp
);
4232 SSA_NAME_DEF_STMT (new_temp
) = epilog_stmt
;
4233 gsi_insert_before (&exit_gsi
, epilog_stmt
, GSI_SAME_STMT
);
4234 if (nested_in_vect_loop
)
4236 set_vinfo_for_stmt (epilog_stmt
,
4237 new_stmt_vec_info (epilog_stmt
, loop_vinfo
,
4239 STMT_VINFO_RELATED_STMT (vinfo_for_stmt (epilog_stmt
)) =
4240 STMT_VINFO_RELATED_STMT (vinfo_for_stmt (new_phi
));
4243 scalar_results
.quick_push (new_temp
);
4245 scalar_results
[0] = new_temp
;
4248 scalar_results
[0] = new_temp
;
4250 new_phis
[0] = epilog_stmt
;
4253 /* 2.6 Handle the loop-exit phis. Replace the uses of scalar loop-exit
4254 phis with new adjusted scalar results, i.e., replace use <s_out0>
4259 s_out0 = phi <s_loop> # (scalar) EXIT_PHI
4260 v_out1 = phi <VECT_DEF> # NEW_EXIT_PHI
4261 v_out2 = reduce <v_out1>
4262 s_out3 = extract_field <v_out2, 0>
4263 s_out4 = adjust_result <s_out3>
4270 s_out0 = phi <s_loop> # (scalar) EXIT_PHI
4271 v_out1 = phi <VECT_DEF> # NEW_EXIT_PHI
4272 v_out2 = reduce <v_out1>
4273 s_out3 = extract_field <v_out2, 0>
4274 s_out4 = adjust_result <s_out3>
4279 /* In SLP reduction chain we reduce vector results into one vector if
4280 necessary, hence we set here GROUP_SIZE to 1. SCALAR_DEST is the LHS of
4281 the last stmt in the reduction chain, since we are looking for the loop
4283 if (GROUP_FIRST_ELEMENT (vinfo_for_stmt (stmt
)))
4285 scalar_dest
= gimple_assign_lhs (
4286 SLP_TREE_SCALAR_STMTS (slp_node
)[group_size
- 1]);
4290 /* In SLP we may have several statements in NEW_PHIS and REDUCTION_PHIS (in
4291 case that GROUP_SIZE is greater than vectorization factor). Therefore, we
4292 need to match SCALAR_RESULTS with corresponding statements. The first
4293 (GROUP_SIZE / number of new vector stmts) scalar results correspond to
4294 the first vector stmt, etc.
4295 (RATIO is equal to (GROUP_SIZE / number of new vector stmts)). */
4296 if (group_size
> new_phis
.length ())
4298 ratio
= group_size
/ new_phis
.length ();
4299 gcc_assert (!(group_size
% new_phis
.length ()));
4304 for (k
= 0; k
< group_size
; k
++)
4308 epilog_stmt
= new_phis
[k
/ ratio
];
4309 reduction_phi
= reduction_phis
[k
/ ratio
];
4311 inner_phi
= inner_phis
[k
/ ratio
];
4316 gimple current_stmt
= SLP_TREE_SCALAR_STMTS (slp_node
)[k
];
4318 orig_stmt
= STMT_VINFO_RELATED_STMT (vinfo_for_stmt (current_stmt
));
4319 /* SLP statements can't participate in patterns. */
4320 gcc_assert (!orig_stmt
);
4321 scalar_dest
= gimple_assign_lhs (current_stmt
);
4325 /* Find the loop-closed-use at the loop exit of the original scalar
4326 result. (The reduction result is expected to have two immediate uses -
4327 one at the latch block, and one at the loop exit). */
4328 FOR_EACH_IMM_USE_FAST (use_p
, imm_iter
, scalar_dest
)
4329 if (!flow_bb_inside_loop_p (loop
, gimple_bb (USE_STMT (use_p
))))
4330 phis
.safe_push (USE_STMT (use_p
));
4332 /* We expect to have found an exit_phi because of loop-closed-ssa
4334 gcc_assert (!phis
.is_empty ());
4336 FOR_EACH_VEC_ELT (phis
, i
, exit_phi
)
4340 stmt_vec_info exit_phi_vinfo
= vinfo_for_stmt (exit_phi
);
4343 /* FORNOW. Currently not supporting the case that an inner-loop
4344 reduction is not used in the outer-loop (but only outside the
4345 outer-loop), unless it is double reduction. */
4346 gcc_assert ((STMT_VINFO_RELEVANT_P (exit_phi_vinfo
)
4347 && !STMT_VINFO_LIVE_P (exit_phi_vinfo
))
4350 STMT_VINFO_VEC_STMT (exit_phi_vinfo
) = epilog_stmt
;
4352 || STMT_VINFO_DEF_TYPE (exit_phi_vinfo
)
4353 != vect_double_reduction_def
)
4356 /* Handle double reduction:
4358 stmt1: s1 = phi <s0, s2> - double reduction phi (outer loop)
4359 stmt2: s3 = phi <s1, s4> - (regular) reduc phi (inner loop)
4360 stmt3: s4 = use (s3) - (regular) reduc stmt (inner loop)
4361 stmt4: s2 = phi <s4> - double reduction stmt (outer loop)
4363 At that point the regular reduction (stmt2 and stmt3) is
4364 already vectorized, as well as the exit phi node, stmt4.
4365 Here we vectorize the phi node of double reduction, stmt1, and
4366 update all relevant statements. */
4368 /* Go through all the uses of s2 to find double reduction phi
4369 node, i.e., stmt1 above. */
4370 orig_name
= PHI_RESULT (exit_phi
);
4371 FOR_EACH_IMM_USE_STMT (use_stmt
, imm_iter
, orig_name
)
4373 stmt_vec_info use_stmt_vinfo
;
4374 stmt_vec_info new_phi_vinfo
;
4375 tree vect_phi_init
, preheader_arg
, vect_phi_res
, init_def
;
4376 basic_block bb
= gimple_bb (use_stmt
);
4379 /* Check that USE_STMT is really double reduction phi
4381 if (gimple_code (use_stmt
) != GIMPLE_PHI
4382 || gimple_phi_num_args (use_stmt
) != 2
4383 || bb
->loop_father
!= outer_loop
)
4385 use_stmt_vinfo
= vinfo_for_stmt (use_stmt
);
4387 || STMT_VINFO_DEF_TYPE (use_stmt_vinfo
)
4388 != vect_double_reduction_def
)
4391 /* Create vector phi node for double reduction:
4392 vs1 = phi <vs0, vs2>
4393 vs1 was created previously in this function by a call to
4394 vect_get_vec_def_for_operand and is stored in
4396 vs2 is defined by INNER_PHI, the vectorized EXIT_PHI;
4397 vs0 is created here. */
4399 /* Create vector phi node. */
4400 vect_phi
= create_phi_node (vec_initial_def
, bb
);
4401 new_phi_vinfo
= new_stmt_vec_info (vect_phi
,
4402 loop_vec_info_for_loop (outer_loop
), NULL
);
4403 set_vinfo_for_stmt (vect_phi
, new_phi_vinfo
);
4405 /* Create vs0 - initial def of the double reduction phi. */
4406 preheader_arg
= PHI_ARG_DEF_FROM_EDGE (use_stmt
,
4407 loop_preheader_edge (outer_loop
));
4408 init_def
= get_initial_def_for_reduction (stmt
,
4409 preheader_arg
, NULL
);
4410 vect_phi_init
= vect_init_vector (use_stmt
, init_def
,
4413 /* Update phi node arguments with vs0 and vs2. */
4414 add_phi_arg (vect_phi
, vect_phi_init
,
4415 loop_preheader_edge (outer_loop
),
4417 add_phi_arg (vect_phi
, PHI_RESULT (inner_phi
),
4418 loop_latch_edge (outer_loop
), UNKNOWN_LOCATION
);
4419 if (dump_enabled_p ())
4421 dump_printf_loc (MSG_NOTE
, vect_location
,
4422 "created double reduction phi node: ");
4423 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, vect_phi
, 0);
4426 vect_phi_res
= PHI_RESULT (vect_phi
);
4428 /* Replace the use, i.e., set the correct vs1 in the regular
4429 reduction phi node. FORNOW, NCOPIES is always 1, so the
4430 loop is redundant. */
4431 use
= reduction_phi
;
4432 for (j
= 0; j
< ncopies
; j
++)
4434 edge pr_edge
= loop_preheader_edge (loop
);
4435 SET_PHI_ARG_DEF (use
, pr_edge
->dest_idx
, vect_phi_res
);
4436 use
= STMT_VINFO_RELATED_STMT (vinfo_for_stmt (use
));
4443 if (nested_in_vect_loop
)
4452 /* Find the loop-closed-use at the loop exit of the original scalar
4453 result. (The reduction result is expected to have two immediate uses,
4454 one at the latch block, and one at the loop exit). For double
4455 reductions we are looking for exit phis of the outer loop. */
4456 FOR_EACH_IMM_USE_FAST (use_p
, imm_iter
, scalar_dest
)
4458 if (!flow_bb_inside_loop_p (loop
, gimple_bb (USE_STMT (use_p
))))
4459 phis
.safe_push (USE_STMT (use_p
));
4462 if (double_reduc
&& gimple_code (USE_STMT (use_p
)) == GIMPLE_PHI
)
4464 tree phi_res
= PHI_RESULT (USE_STMT (use_p
));
4466 FOR_EACH_IMM_USE_FAST (phi_use_p
, phi_imm_iter
, phi_res
)
4468 if (!flow_bb_inside_loop_p (loop
,
4469 gimple_bb (USE_STMT (phi_use_p
))))
4470 phis
.safe_push (USE_STMT (phi_use_p
));
4476 FOR_EACH_VEC_ELT (phis
, i
, exit_phi
)
4478 /* Replace the uses: */
4479 orig_name
= PHI_RESULT (exit_phi
);
4480 scalar_result
= scalar_results
[k
];
4481 FOR_EACH_IMM_USE_STMT (use_stmt
, imm_iter
, orig_name
)
4482 FOR_EACH_IMM_USE_ON_STMT (use_p
, imm_iter
)
4483 SET_USE (use_p
, scalar_result
);
4489 scalar_results
.release ();
4490 inner_phis
.release ();
4491 new_phis
.release ();
4495 /* Function vectorizable_reduction.
4497 Check if STMT performs a reduction operation that can be vectorized.
4498 If VEC_STMT is also passed, vectorize the STMT: create a vectorized
4499 stmt to replace it, put it in VEC_STMT, and insert it at GSI.
4500 Return FALSE if not a vectorizable STMT, TRUE otherwise.
4502 This function also handles reduction idioms (patterns) that have been
4503 recognized in advance during vect_pattern_recog. In this case, STMT may be
4505 X = pattern_expr (arg0, arg1, ..., X)
4506 and it's STMT_VINFO_RELATED_STMT points to the last stmt in the original
4507 sequence that had been detected and replaced by the pattern-stmt (STMT).
4509 In some cases of reduction patterns, the type of the reduction variable X is
4510 different than the type of the other arguments of STMT.
4511 In such cases, the vectype that is used when transforming STMT into a vector
4512 stmt is different than the vectype that is used to determine the
4513 vectorization factor, because it consists of a different number of elements
4514 than the actual number of elements that are being operated upon in parallel.
4516 For example, consider an accumulation of shorts into an int accumulator.
4517 On some targets it's possible to vectorize this pattern operating on 8
4518 shorts at a time (hence, the vectype for purposes of determining the
4519 vectorization factor should be V8HI); on the other hand, the vectype that
4520 is used to create the vector form is actually V4SI (the type of the result).
4522 Upon entry to this function, STMT_VINFO_VECTYPE records the vectype that
4523 indicates what is the actual level of parallelism (V8HI in the example), so
4524 that the right vectorization factor would be derived. This vectype
4525 corresponds to the type of arguments to the reduction stmt, and should *NOT*
4526 be used to create the vectorized stmt. The right vectype for the vectorized
4527 stmt is obtained from the type of the result X:
4528 get_vectype_for_scalar_type (TREE_TYPE (X))
4530 This means that, contrary to "regular" reductions (or "regular" stmts in
4531 general), the following equation:
4532 STMT_VINFO_VECTYPE == get_vectype_for_scalar_type (TREE_TYPE (X))
4533 does *NOT* necessarily hold for reduction patterns. */
4536 vectorizable_reduction (gimple stmt
, gimple_stmt_iterator
*gsi
,
4537 gimple
*vec_stmt
, slp_tree slp_node
)
4541 tree loop_vec_def0
= NULL_TREE
, loop_vec_def1
= NULL_TREE
;
4542 stmt_vec_info stmt_info
= vinfo_for_stmt (stmt
);
4543 tree vectype_out
= STMT_VINFO_VECTYPE (stmt_info
);
4544 tree vectype_in
= NULL_TREE
;
4545 loop_vec_info loop_vinfo
= STMT_VINFO_LOOP_VINFO (stmt_info
);
4546 struct loop
*loop
= LOOP_VINFO_LOOP (loop_vinfo
);
4547 enum tree_code code
, orig_code
, epilog_reduc_code
;
4548 enum machine_mode vec_mode
;
4550 optab optab
, reduc_optab
;
4551 tree new_temp
= NULL_TREE
;
4554 enum vect_def_type dt
;
4555 gimple new_phi
= NULL
;
4559 stmt_vec_info orig_stmt_info
;
4560 tree expr
= NULL_TREE
;
4564 stmt_vec_info prev_stmt_info
, prev_phi_info
;
4565 bool single_defuse_cycle
= false;
4566 tree reduc_def
= NULL_TREE
;
4567 gimple new_stmt
= NULL
;
4570 bool nested_cycle
= false, found_nested_cycle_def
= false;
4571 gimple reduc_def_stmt
= NULL
;
4572 /* The default is that the reduction variable is the last in statement. */
4573 int reduc_index
= 2;
4574 bool double_reduc
= false, dummy
;
4576 struct loop
* def_stmt_loop
, *outer_loop
= NULL
;
4578 gimple def_arg_stmt
;
4579 vec
<tree
> vec_oprnds0
= vNULL
;
4580 vec
<tree
> vec_oprnds1
= vNULL
;
4581 vec
<tree
> vect_defs
= vNULL
;
4582 vec
<gimple
> phis
= vNULL
;
4584 tree def0
, def1
, tem
, op0
, op1
= NULL_TREE
;
4586 /* In case of reduction chain we switch to the first stmt in the chain, but
4587 we don't update STMT_INFO, since only the last stmt is marked as reduction
4588 and has reduction properties. */
4589 if (GROUP_FIRST_ELEMENT (vinfo_for_stmt (stmt
)))
4590 stmt
= GROUP_FIRST_ELEMENT (stmt_info
);
4592 if (nested_in_vect_loop_p (loop
, stmt
))
4596 nested_cycle
= true;
4599 /* 1. Is vectorizable reduction? */
4600 /* Not supportable if the reduction variable is used in the loop, unless
4601 it's a reduction chain. */
4602 if (STMT_VINFO_RELEVANT (stmt_info
) > vect_used_in_outer
4603 && !GROUP_FIRST_ELEMENT (stmt_info
))
4606 /* Reductions that are not used even in an enclosing outer-loop,
4607 are expected to be "live" (used out of the loop). */
4608 if (STMT_VINFO_RELEVANT (stmt_info
) == vect_unused_in_scope
4609 && !STMT_VINFO_LIVE_P (stmt_info
))
4612 /* Make sure it was already recognized as a reduction computation. */
4613 if (STMT_VINFO_DEF_TYPE (stmt_info
) != vect_reduction_def
4614 && STMT_VINFO_DEF_TYPE (stmt_info
) != vect_nested_cycle
)
4617 /* 2. Has this been recognized as a reduction pattern?
4619 Check if STMT represents a pattern that has been recognized
4620 in earlier analysis stages. For stmts that represent a pattern,
4621 the STMT_VINFO_RELATED_STMT field records the last stmt in
4622 the original sequence that constitutes the pattern. */
4624 orig_stmt
= STMT_VINFO_RELATED_STMT (stmt_info
);
4627 orig_stmt_info
= vinfo_for_stmt (orig_stmt
);
4628 gcc_assert (STMT_VINFO_IN_PATTERN_P (orig_stmt_info
));
4629 gcc_assert (!STMT_VINFO_IN_PATTERN_P (stmt_info
));
4632 /* 3. Check the operands of the operation. The first operands are defined
4633 inside the loop body. The last operand is the reduction variable,
4634 which is defined by the loop-header-phi. */
4636 gcc_assert (is_gimple_assign (stmt
));
4639 switch (get_gimple_rhs_class (gimple_assign_rhs_code (stmt
)))
4641 case GIMPLE_SINGLE_RHS
:
4642 op_type
= TREE_OPERAND_LENGTH (gimple_assign_rhs1 (stmt
));
4643 if (op_type
== ternary_op
)
4645 tree rhs
= gimple_assign_rhs1 (stmt
);
4646 ops
[0] = TREE_OPERAND (rhs
, 0);
4647 ops
[1] = TREE_OPERAND (rhs
, 1);
4648 ops
[2] = TREE_OPERAND (rhs
, 2);
4649 code
= TREE_CODE (rhs
);
4655 case GIMPLE_BINARY_RHS
:
4656 code
= gimple_assign_rhs_code (stmt
);
4657 op_type
= TREE_CODE_LENGTH (code
);
4658 gcc_assert (op_type
== binary_op
);
4659 ops
[0] = gimple_assign_rhs1 (stmt
);
4660 ops
[1] = gimple_assign_rhs2 (stmt
);
4663 case GIMPLE_TERNARY_RHS
:
4664 code
= gimple_assign_rhs_code (stmt
);
4665 op_type
= TREE_CODE_LENGTH (code
);
4666 gcc_assert (op_type
== ternary_op
);
4667 ops
[0] = gimple_assign_rhs1 (stmt
);
4668 ops
[1] = gimple_assign_rhs2 (stmt
);
4669 ops
[2] = gimple_assign_rhs3 (stmt
);
4672 case GIMPLE_UNARY_RHS
:
4679 if (code
== COND_EXPR
&& slp_node
)
4682 scalar_dest
= gimple_assign_lhs (stmt
);
4683 scalar_type
= TREE_TYPE (scalar_dest
);
4684 if (!POINTER_TYPE_P (scalar_type
) && !INTEGRAL_TYPE_P (scalar_type
)
4685 && !SCALAR_FLOAT_TYPE_P (scalar_type
))
4688 /* Do not try to vectorize bit-precision reductions. */
4689 if ((TYPE_PRECISION (scalar_type
)
4690 != GET_MODE_PRECISION (TYPE_MODE (scalar_type
))))
4693 /* All uses but the last are expected to be defined in the loop.
4694 The last use is the reduction variable. In case of nested cycle this
4695 assumption is not true: we use reduc_index to record the index of the
4696 reduction variable. */
4697 for (i
= 0; i
< op_type
- 1; i
++)
4699 /* The condition of COND_EXPR is checked in vectorizable_condition(). */
4700 if (i
== 0 && code
== COND_EXPR
)
4703 is_simple_use
= vect_is_simple_use_1 (ops
[i
], stmt
, loop_vinfo
, NULL
,
4704 &def_stmt
, &def
, &dt
, &tem
);
4707 gcc_assert (is_simple_use
);
4709 if (dt
!= vect_internal_def
4710 && dt
!= vect_external_def
4711 && dt
!= vect_constant_def
4712 && dt
!= vect_induction_def
4713 && !(dt
== vect_nested_cycle
&& nested_cycle
))
4716 if (dt
== vect_nested_cycle
)
4718 found_nested_cycle_def
= true;
4719 reduc_def_stmt
= def_stmt
;
4724 is_simple_use
= vect_is_simple_use_1 (ops
[i
], stmt
, loop_vinfo
, NULL
,
4725 &def_stmt
, &def
, &dt
, &tem
);
4728 gcc_assert (is_simple_use
);
4729 if (!(dt
== vect_reduction_def
4730 || dt
== vect_nested_cycle
4731 || ((dt
== vect_internal_def
|| dt
== vect_external_def
4732 || dt
== vect_constant_def
|| dt
== vect_induction_def
)
4733 && nested_cycle
&& found_nested_cycle_def
)))
4735 /* For pattern recognized stmts, orig_stmt might be a reduction,
4736 but some helper statements for the pattern might not, or
4737 might be COND_EXPRs with reduction uses in the condition. */
4738 gcc_assert (orig_stmt
);
4741 if (!found_nested_cycle_def
)
4742 reduc_def_stmt
= def_stmt
;
4744 gcc_assert (gimple_code (reduc_def_stmt
) == GIMPLE_PHI
);
4746 gcc_assert (orig_stmt
== vect_is_simple_reduction (loop_vinfo
,
4752 gimple tmp
= vect_is_simple_reduction (loop_vinfo
, reduc_def_stmt
,
4753 !nested_cycle
, &dummy
);
4754 /* We changed STMT to be the first stmt in reduction chain, hence we
4755 check that in this case the first element in the chain is STMT. */
4756 gcc_assert (stmt
== tmp
4757 || GROUP_FIRST_ELEMENT (vinfo_for_stmt (tmp
)) == stmt
);
4760 if (STMT_VINFO_LIVE_P (vinfo_for_stmt (reduc_def_stmt
)))
4763 if (slp_node
|| PURE_SLP_STMT (stmt_info
))
4766 ncopies
= (LOOP_VINFO_VECT_FACTOR (loop_vinfo
)
4767 / TYPE_VECTOR_SUBPARTS (vectype_in
));
4769 gcc_assert (ncopies
>= 1);
4771 vec_mode
= TYPE_MODE (vectype_in
);
4773 if (code
== COND_EXPR
)
4775 if (!vectorizable_condition (stmt
, gsi
, NULL
, ops
[reduc_index
], 0, NULL
))
4777 if (dump_enabled_p ())
4778 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
4779 "unsupported condition in reduction");
4786 /* 4. Supportable by target? */
4788 if (code
== LSHIFT_EXPR
|| code
== RSHIFT_EXPR
4789 || code
== LROTATE_EXPR
|| code
== RROTATE_EXPR
)
4791 /* Shifts and rotates are only supported by vectorizable_shifts,
4792 not vectorizable_reduction. */
4793 if (dump_enabled_p ())
4794 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
4795 "unsupported shift or rotation.");
4799 /* 4.1. check support for the operation in the loop */
4800 optab
= optab_for_tree_code (code
, vectype_in
, optab_default
);
4803 if (dump_enabled_p ())
4804 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
4810 if (optab_handler (optab
, vec_mode
) == CODE_FOR_nothing
)
4812 if (dump_enabled_p ())
4813 dump_printf (MSG_NOTE
, "op not supported by target.");
4815 if (GET_MODE_SIZE (vec_mode
) != UNITS_PER_WORD
4816 || LOOP_VINFO_VECT_FACTOR (loop_vinfo
)
4817 < vect_min_worthwhile_factor (code
))
4820 if (dump_enabled_p ())
4821 dump_printf (MSG_NOTE
, "proceeding using word mode.");
4824 /* Worthwhile without SIMD support? */
4825 if (!VECTOR_MODE_P (TYPE_MODE (vectype_in
))
4826 && LOOP_VINFO_VECT_FACTOR (loop_vinfo
)
4827 < vect_min_worthwhile_factor (code
))
4829 if (dump_enabled_p ())
4830 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
4831 "not worthwhile without SIMD support.");
4837 /* 4.2. Check support for the epilog operation.
4839 If STMT represents a reduction pattern, then the type of the
4840 reduction variable may be different than the type of the rest
4841 of the arguments. For example, consider the case of accumulation
4842 of shorts into an int accumulator; The original code:
4843 S1: int_a = (int) short_a;
4844 orig_stmt-> S2: int_acc = plus <int_a ,int_acc>;
4847 STMT: int_acc = widen_sum <short_a, int_acc>
4850 1. The tree-code that is used to create the vector operation in the
4851 epilog code (that reduces the partial results) is not the
4852 tree-code of STMT, but is rather the tree-code of the original
4853 stmt from the pattern that STMT is replacing. I.e, in the example
4854 above we want to use 'widen_sum' in the loop, but 'plus' in the
4856 2. The type (mode) we use to check available target support
4857 for the vector operation to be created in the *epilog*, is
4858 determined by the type of the reduction variable (in the example
4859 above we'd check this: optab_handler (plus_optab, vect_int_mode])).
4860 However the type (mode) we use to check available target support
4861 for the vector operation to be created *inside the loop*, is
4862 determined by the type of the other arguments to STMT (in the
4863 example we'd check this: optab_handler (widen_sum_optab,
4866 This is contrary to "regular" reductions, in which the types of all
4867 the arguments are the same as the type of the reduction variable.
4868 For "regular" reductions we can therefore use the same vector type
4869 (and also the same tree-code) when generating the epilog code and
4870 when generating the code inside the loop. */
4874 /* This is a reduction pattern: get the vectype from the type of the
4875 reduction variable, and get the tree-code from orig_stmt. */
4876 orig_code
= gimple_assign_rhs_code (orig_stmt
);
4877 gcc_assert (vectype_out
);
4878 vec_mode
= TYPE_MODE (vectype_out
);
4882 /* Regular reduction: use the same vectype and tree-code as used for
4883 the vector code inside the loop can be used for the epilog code. */
4889 def_bb
= gimple_bb (reduc_def_stmt
);
4890 def_stmt_loop
= def_bb
->loop_father
;
4891 def_arg
= PHI_ARG_DEF_FROM_EDGE (reduc_def_stmt
,
4892 loop_preheader_edge (def_stmt_loop
));
4893 if (TREE_CODE (def_arg
) == SSA_NAME
4894 && (def_arg_stmt
= SSA_NAME_DEF_STMT (def_arg
))
4895 && gimple_code (def_arg_stmt
) == GIMPLE_PHI
4896 && flow_bb_inside_loop_p (outer_loop
, gimple_bb (def_arg_stmt
))
4897 && vinfo_for_stmt (def_arg_stmt
)
4898 && STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def_arg_stmt
))
4899 == vect_double_reduction_def
)
4900 double_reduc
= true;
4903 epilog_reduc_code
= ERROR_MARK
;
4904 if (reduction_code_for_scalar_code (orig_code
, &epilog_reduc_code
))
4906 reduc_optab
= optab_for_tree_code (epilog_reduc_code
, vectype_out
,
4910 if (dump_enabled_p ())
4911 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
4912 "no optab for reduction.");
4914 epilog_reduc_code
= ERROR_MARK
;
4918 && optab_handler (reduc_optab
, vec_mode
) == CODE_FOR_nothing
)
4920 if (dump_enabled_p ())
4921 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
4922 "reduc op not supported by target.");
4924 epilog_reduc_code
= ERROR_MARK
;
4929 if (!nested_cycle
|| double_reduc
)
4931 if (dump_enabled_p ())
4932 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
4933 "no reduc code for scalar code.");
4939 if (double_reduc
&& ncopies
> 1)
4941 if (dump_enabled_p ())
4942 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
4943 "multiple types in double reduction");
4948 /* In case of widenning multiplication by a constant, we update the type
4949 of the constant to be the type of the other operand. We check that the
4950 constant fits the type in the pattern recognition pass. */
4951 if (code
== DOT_PROD_EXPR
4952 && !types_compatible_p (TREE_TYPE (ops
[0]), TREE_TYPE (ops
[1])))
4954 if (TREE_CODE (ops
[0]) == INTEGER_CST
)
4955 ops
[0] = fold_convert (TREE_TYPE (ops
[1]), ops
[0]);
4956 else if (TREE_CODE (ops
[1]) == INTEGER_CST
)
4957 ops
[1] = fold_convert (TREE_TYPE (ops
[0]), ops
[1]);
4960 if (dump_enabled_p ())
4961 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
4962 "invalid types in dot-prod");
4968 if (!vec_stmt
) /* transformation not required. */
4970 if (!vect_model_reduction_cost (stmt_info
, epilog_reduc_code
, ncopies
))
4972 STMT_VINFO_TYPE (stmt_info
) = reduc_vec_info_type
;
4978 if (dump_enabled_p ())
4979 dump_printf_loc (MSG_NOTE
, vect_location
, "transform reduction.");
4981 /* FORNOW: Multiple types are not supported for condition. */
4982 if (code
== COND_EXPR
)
4983 gcc_assert (ncopies
== 1);
4985 /* Create the destination vector */
4986 vec_dest
= vect_create_destination_var (scalar_dest
, vectype_out
);
4988 /* In case the vectorization factor (VF) is bigger than the number
4989 of elements that we can fit in a vectype (nunits), we have to generate
4990 more than one vector stmt - i.e - we need to "unroll" the
4991 vector stmt by a factor VF/nunits. For more details see documentation
4992 in vectorizable_operation. */
4994 /* If the reduction is used in an outer loop we need to generate
4995 VF intermediate results, like so (e.g. for ncopies=2):
5000 (i.e. we generate VF results in 2 registers).
5001 In this case we have a separate def-use cycle for each copy, and therefore
5002 for each copy we get the vector def for the reduction variable from the
5003 respective phi node created for this copy.
5005 Otherwise (the reduction is unused in the loop nest), we can combine
5006 together intermediate results, like so (e.g. for ncopies=2):
5010 (i.e. we generate VF/2 results in a single register).
5011 In this case for each copy we get the vector def for the reduction variable
5012 from the vectorized reduction operation generated in the previous iteration.
5015 if (STMT_VINFO_RELEVANT (stmt_info
) == vect_unused_in_scope
)
5017 single_defuse_cycle
= true;
5021 epilog_copies
= ncopies
;
5023 prev_stmt_info
= NULL
;
5024 prev_phi_info
= NULL
;
5027 vec_num
= SLP_TREE_NUMBER_OF_VEC_STMTS (slp_node
);
5028 gcc_assert (TYPE_VECTOR_SUBPARTS (vectype_out
)
5029 == TYPE_VECTOR_SUBPARTS (vectype_in
));
5034 vec_oprnds0
.create (1);
5035 if (op_type
== ternary_op
)
5036 vec_oprnds1
.create (1);
5039 phis
.create (vec_num
);
5040 vect_defs
.create (vec_num
);
5042 vect_defs
.quick_push (NULL_TREE
);
5044 for (j
= 0; j
< ncopies
; j
++)
5046 if (j
== 0 || !single_defuse_cycle
)
5048 for (i
= 0; i
< vec_num
; i
++)
5050 /* Create the reduction-phi that defines the reduction
5052 new_phi
= create_phi_node (vec_dest
, loop
->header
);
5053 set_vinfo_for_stmt (new_phi
,
5054 new_stmt_vec_info (new_phi
, loop_vinfo
,
5056 if (j
== 0 || slp_node
)
5057 phis
.quick_push (new_phi
);
5061 if (code
== COND_EXPR
)
5063 gcc_assert (!slp_node
);
5064 vectorizable_condition (stmt
, gsi
, vec_stmt
,
5065 PHI_RESULT (phis
[0]),
5067 /* Multiple types are not supported for condition. */
5074 op0
= ops
[!reduc_index
];
5075 if (op_type
== ternary_op
)
5077 if (reduc_index
== 0)
5084 vect_get_vec_defs (op0
, op1
, stmt
, &vec_oprnds0
, &vec_oprnds1
,
5088 loop_vec_def0
= vect_get_vec_def_for_operand (ops
[!reduc_index
],
5090 vec_oprnds0
.quick_push (loop_vec_def0
);
5091 if (op_type
== ternary_op
)
5093 loop_vec_def1
= vect_get_vec_def_for_operand (op1
, stmt
,
5095 vec_oprnds1
.quick_push (loop_vec_def1
);
5103 enum vect_def_type dt
;
5107 vect_is_simple_use (ops
[!reduc_index
], stmt
, loop_vinfo
, NULL
,
5108 &dummy_stmt
, &dummy
, &dt
);
5109 loop_vec_def0
= vect_get_vec_def_for_stmt_copy (dt
,
5111 vec_oprnds0
[0] = loop_vec_def0
;
5112 if (op_type
== ternary_op
)
5114 vect_is_simple_use (op1
, stmt
, loop_vinfo
, NULL
, &dummy_stmt
,
5116 loop_vec_def1
= vect_get_vec_def_for_stmt_copy (dt
,
5118 vec_oprnds1
[0] = loop_vec_def1
;
5122 if (single_defuse_cycle
)
5123 reduc_def
= gimple_assign_lhs (new_stmt
);
5125 STMT_VINFO_RELATED_STMT (prev_phi_info
) = new_phi
;
5128 FOR_EACH_VEC_ELT (vec_oprnds0
, i
, def0
)
5131 reduc_def
= PHI_RESULT (phis
[i
]);
5134 if (!single_defuse_cycle
|| j
== 0)
5135 reduc_def
= PHI_RESULT (new_phi
);
5138 def1
= ((op_type
== ternary_op
)
5139 ? vec_oprnds1
[i
] : NULL
);
5140 if (op_type
== binary_op
)
5142 if (reduc_index
== 0)
5143 expr
= build2 (code
, vectype_out
, reduc_def
, def0
);
5145 expr
= build2 (code
, vectype_out
, def0
, reduc_def
);
5149 if (reduc_index
== 0)
5150 expr
= build3 (code
, vectype_out
, reduc_def
, def0
, def1
);
5153 if (reduc_index
== 1)
5154 expr
= build3 (code
, vectype_out
, def0
, reduc_def
, def1
);
5156 expr
= build3 (code
, vectype_out
, def0
, def1
, reduc_def
);
5160 new_stmt
= gimple_build_assign (vec_dest
, expr
);
5161 new_temp
= make_ssa_name (vec_dest
, new_stmt
);
5162 gimple_assign_set_lhs (new_stmt
, new_temp
);
5163 vect_finish_stmt_generation (stmt
, new_stmt
, gsi
);
5167 SLP_TREE_VEC_STMTS (slp_node
).quick_push (new_stmt
);
5168 vect_defs
.quick_push (new_temp
);
5171 vect_defs
[0] = new_temp
;
5178 STMT_VINFO_VEC_STMT (stmt_info
) = *vec_stmt
= new_stmt
;
5180 STMT_VINFO_RELATED_STMT (prev_stmt_info
) = new_stmt
;
5182 prev_stmt_info
= vinfo_for_stmt (new_stmt
);
5183 prev_phi_info
= vinfo_for_stmt (new_phi
);
5186 /* Finalize the reduction-phi (set its arguments) and create the
5187 epilog reduction code. */
5188 if ((!single_defuse_cycle
|| code
== COND_EXPR
) && !slp_node
)
5190 new_temp
= gimple_assign_lhs (*vec_stmt
);
5191 vect_defs
[0] = new_temp
;
5194 vect_create_epilog_for_reduction (vect_defs
, stmt
, epilog_copies
,
5195 epilog_reduc_code
, phis
, reduc_index
,
5196 double_reduc
, slp_node
);
5199 vect_defs
.release ();
5200 vec_oprnds0
.release ();
5201 vec_oprnds1
.release ();
5206 /* Function vect_min_worthwhile_factor.
5208 For a loop where we could vectorize the operation indicated by CODE,
5209 return the minimum vectorization factor that makes it worthwhile
5210 to use generic vectors. */
5212 vect_min_worthwhile_factor (enum tree_code code
)
5233 /* Function vectorizable_induction
5235 Check if PHI performs an induction computation that can be vectorized.
5236 If VEC_STMT is also passed, vectorize the induction PHI: create a vectorized
5237 phi to replace it, put it in VEC_STMT, and add it to the same basic block.
5238 Return FALSE if not a vectorizable STMT, TRUE otherwise. */
5241 vectorizable_induction (gimple phi
, gimple_stmt_iterator
*gsi ATTRIBUTE_UNUSED
,
5244 stmt_vec_info stmt_info
= vinfo_for_stmt (phi
);
5245 tree vectype
= STMT_VINFO_VECTYPE (stmt_info
);
5246 loop_vec_info loop_vinfo
= STMT_VINFO_LOOP_VINFO (stmt_info
);
5247 struct loop
*loop
= LOOP_VINFO_LOOP (loop_vinfo
);
5248 int nunits
= TYPE_VECTOR_SUBPARTS (vectype
);
5249 int ncopies
= LOOP_VINFO_VECT_FACTOR (loop_vinfo
) / nunits
;
5252 gcc_assert (ncopies
>= 1);
5253 /* FORNOW. These restrictions should be relaxed. */
5254 if (nested_in_vect_loop_p (loop
, phi
))
5256 imm_use_iterator imm_iter
;
5257 use_operand_p use_p
;
5264 if (dump_enabled_p ())
5265 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
5266 "multiple types in nested loop.");
5271 latch_e
= loop_latch_edge (loop
->inner
);
5272 loop_arg
= PHI_ARG_DEF_FROM_EDGE (phi
, latch_e
);
5273 FOR_EACH_IMM_USE_FAST (use_p
, imm_iter
, loop_arg
)
5275 if (!flow_bb_inside_loop_p (loop
->inner
,
5276 gimple_bb (USE_STMT (use_p
))))
5278 exit_phi
= USE_STMT (use_p
);
5284 stmt_vec_info exit_phi_vinfo
= vinfo_for_stmt (exit_phi
);
5285 if (!(STMT_VINFO_RELEVANT_P (exit_phi_vinfo
)
5286 && !STMT_VINFO_LIVE_P (exit_phi_vinfo
)))
5288 if (dump_enabled_p ())
5289 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
5290 "inner-loop induction only used outside "
5291 "of the outer vectorized loop.");
5297 if (!STMT_VINFO_RELEVANT_P (stmt_info
))
5300 /* FORNOW: SLP not supported. */
5301 if (STMT_SLP_TYPE (stmt_info
))
5304 gcc_assert (STMT_VINFO_DEF_TYPE (stmt_info
) == vect_induction_def
);
5306 if (gimple_code (phi
) != GIMPLE_PHI
)
5309 if (!vec_stmt
) /* transformation not required. */
5311 STMT_VINFO_TYPE (stmt_info
) = induc_vec_info_type
;
5312 if (dump_enabled_p ())
5313 dump_printf_loc (MSG_NOTE
, vect_location
,
5314 "=== vectorizable_induction ===");
5315 vect_model_induction_cost (stmt_info
, ncopies
);
5321 if (dump_enabled_p ())
5322 dump_printf_loc (MSG_NOTE
, vect_location
, "transform induction phi.");
5324 vec_def
= get_initial_def_for_induction (phi
);
5325 *vec_stmt
= SSA_NAME_DEF_STMT (vec_def
);
5329 /* Function vectorizable_live_operation.
5331 STMT computes a value that is used outside the loop. Check if
5332 it can be supported. */
5335 vectorizable_live_operation (gimple stmt
,
5336 gimple_stmt_iterator
*gsi ATTRIBUTE_UNUSED
,
5337 gimple
*vec_stmt ATTRIBUTE_UNUSED
)
5339 stmt_vec_info stmt_info
= vinfo_for_stmt (stmt
);
5340 loop_vec_info loop_vinfo
= STMT_VINFO_LOOP_VINFO (stmt_info
);
5341 struct loop
*loop
= LOOP_VINFO_LOOP (loop_vinfo
);
5347 enum vect_def_type dt
;
5348 enum tree_code code
;
5349 enum gimple_rhs_class rhs_class
;
5351 gcc_assert (STMT_VINFO_LIVE_P (stmt_info
));
5353 if (STMT_VINFO_DEF_TYPE (stmt_info
) == vect_reduction_def
)
5356 if (!is_gimple_assign (stmt
))
5359 if (TREE_CODE (gimple_assign_lhs (stmt
)) != SSA_NAME
)
5362 /* FORNOW. CHECKME. */
5363 if (nested_in_vect_loop_p (loop
, stmt
))
5366 code
= gimple_assign_rhs_code (stmt
);
5367 op_type
= TREE_CODE_LENGTH (code
);
5368 rhs_class
= get_gimple_rhs_class (code
);
5369 gcc_assert (rhs_class
!= GIMPLE_UNARY_RHS
|| op_type
== unary_op
);
5370 gcc_assert (rhs_class
!= GIMPLE_BINARY_RHS
|| op_type
== binary_op
);
5372 /* FORNOW: support only if all uses are invariant. This means
5373 that the scalar operations can remain in place, unvectorized.
5374 The original last scalar value that they compute will be used. */
5376 for (i
= 0; i
< op_type
; i
++)
5378 if (rhs_class
== GIMPLE_SINGLE_RHS
)
5379 op
= TREE_OPERAND (gimple_op (stmt
, 1), i
);
5381 op
= gimple_op (stmt
, i
+ 1);
5383 && !vect_is_simple_use (op
, stmt
, loop_vinfo
, NULL
, &def_stmt
, &def
,
5386 if (dump_enabled_p ())
5387 dump_printf_loc (MSG_MISSED_OPTIMIZATION
, vect_location
,
5392 if (dt
!= vect_external_def
&& dt
!= vect_constant_def
)
5396 /* No transformation is required for the cases we currently support. */
5400 /* Kill any debug uses outside LOOP of SSA names defined in STMT. */
5403 vect_loop_kill_debug_uses (struct loop
*loop
, gimple stmt
)
5405 ssa_op_iter op_iter
;
5406 imm_use_iterator imm_iter
;
5407 def_operand_p def_p
;
5410 FOR_EACH_PHI_OR_STMT_DEF (def_p
, stmt
, op_iter
, SSA_OP_DEF
)
5412 FOR_EACH_IMM_USE_STMT (ustmt
, imm_iter
, DEF_FROM_PTR (def_p
))
5416 if (!is_gimple_debug (ustmt
))
5419 bb
= gimple_bb (ustmt
);
5421 if (!flow_bb_inside_loop_p (loop
, bb
))
5423 if (gimple_debug_bind_p (ustmt
))
5425 if (dump_enabled_p ())
5426 dump_printf_loc (MSG_NOTE
, vect_location
,
5427 "killing debug use");
5429 gimple_debug_bind_reset_value (ustmt
);
5430 update_stmt (ustmt
);
5439 /* Function vect_transform_loop.
5441 The analysis phase has determined that the loop is vectorizable.
5442 Vectorize the loop - created vectorized stmts to replace the scalar
5443 stmts in the loop, and update the loop exit condition. */
5446 vect_transform_loop (loop_vec_info loop_vinfo
)
5448 struct loop
*loop
= LOOP_VINFO_LOOP (loop_vinfo
);
5449 basic_block
*bbs
= LOOP_VINFO_BBS (loop_vinfo
);
5450 int nbbs
= loop
->num_nodes
;
5451 gimple_stmt_iterator si
;
5454 int vectorization_factor
= LOOP_VINFO_VECT_FACTOR (loop_vinfo
);
5456 bool slp_scheduled
= false;
5457 unsigned int nunits
;
5458 gimple stmt
, pattern_stmt
;
5459 gimple_seq pattern_def_seq
= NULL
;
5460 gimple_stmt_iterator pattern_def_si
= gsi_none ();
5461 bool transform_pattern_stmt
= false;
5462 bool check_profitability
= false;
5464 /* Record number of iterations before we started tampering with the profile. */
5465 gcov_type expected_iterations
= expected_loop_iterations_unbounded (loop
);
5467 if (dump_enabled_p ())
5468 dump_printf_loc (MSG_NOTE
, vect_location
, "=== vec_transform_loop ===");
5470 /* If profile is inprecise, we have chance to fix it up. */
5471 if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo
))
5472 expected_iterations
= LOOP_VINFO_INT_NITERS (loop_vinfo
);
5474 /* Use the more conservative vectorization threshold. If the number
5475 of iterations is constant assume the cost check has been performed
5476 by our caller. If the threshold makes all loops profitable that
5477 run at least the vectorization factor number of times checking
5478 is pointless, too. */
5479 th
= ((PARAM_VALUE (PARAM_MIN_VECT_LOOP_BOUND
)
5480 * LOOP_VINFO_VECT_FACTOR (loop_vinfo
)) - 1);
5481 th
= MAX (th
, LOOP_VINFO_COST_MODEL_MIN_ITERS (loop_vinfo
));
5482 if (th
>= LOOP_VINFO_VECT_FACTOR (loop_vinfo
) - 1
5483 && !LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo
))
5485 if (dump_enabled_p ())
5486 dump_printf_loc (MSG_NOTE
, vect_location
,
5487 "Profitability threshold is %d loop iterations.", th
);
5488 check_profitability
= true;
5491 /* Peel the loop if there are data refs with unknown alignment.
5492 Only one data ref with unknown store is allowed. */
5494 if (LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo
))
5496 vect_do_peeling_for_alignment (loop_vinfo
, th
, check_profitability
);
5497 check_profitability
= false;
5500 if (LOOP_REQUIRES_VERSIONING_FOR_ALIGNMENT (loop_vinfo
)
5501 || LOOP_REQUIRES_VERSIONING_FOR_ALIAS (loop_vinfo
))
5503 vect_loop_versioning (loop_vinfo
, th
, check_profitability
);
5504 check_profitability
= false;
5507 /* If the loop has a symbolic number of iterations 'n' (i.e. it's not a
5508 compile time constant), or it is a constant that doesn't divide by the
5509 vectorization factor, then an epilog loop needs to be created.
5510 We therefore duplicate the loop: the original loop will be vectorized,
5511 and will compute the first (n/VF) iterations. The second copy of the loop
5512 will remain scalar and will compute the remaining (n%VF) iterations.
5513 (VF is the vectorization factor). */
5515 if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo
)
5516 || (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo
)
5517 && LOOP_VINFO_INT_NITERS (loop_vinfo
) % vectorization_factor
!= 0)
5518 || LOOP_VINFO_PEELING_FOR_GAPS (loop_vinfo
))
5519 vect_do_peeling_for_loop_bound (loop_vinfo
, &ratio
,
5520 th
, check_profitability
);
5522 ratio
= build_int_cst (TREE_TYPE (LOOP_VINFO_NITERS (loop_vinfo
)),
5523 LOOP_VINFO_INT_NITERS (loop_vinfo
) / vectorization_factor
);
5525 /* 1) Make sure the loop header has exactly two entries
5526 2) Make sure we have a preheader basic block. */
5528 gcc_assert (EDGE_COUNT (loop
->header
->preds
) == 2);
5530 split_edge (loop_preheader_edge (loop
));
5532 /* FORNOW: the vectorizer supports only loops which body consist
5533 of one basic block (header + empty latch). When the vectorizer will
5534 support more involved loop forms, the order by which the BBs are
5535 traversed need to be reconsidered. */
5537 for (i
= 0; i
< nbbs
; i
++)
5539 basic_block bb
= bbs
[i
];
5540 stmt_vec_info stmt_info
;
5543 for (si
= gsi_start_phis (bb
); !gsi_end_p (si
); gsi_next (&si
))
5545 phi
= gsi_stmt (si
);
5546 if (dump_enabled_p ())
5548 dump_printf_loc (MSG_NOTE
, vect_location
,
5549 "------>vectorizing phi: ");
5550 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, phi
, 0);
5552 stmt_info
= vinfo_for_stmt (phi
);
5556 if (MAY_HAVE_DEBUG_STMTS
&& !STMT_VINFO_LIVE_P (stmt_info
))
5557 vect_loop_kill_debug_uses (loop
, phi
);
5559 if (!STMT_VINFO_RELEVANT_P (stmt_info
)
5560 && !STMT_VINFO_LIVE_P (stmt_info
))
5563 if ((TYPE_VECTOR_SUBPARTS (STMT_VINFO_VECTYPE (stmt_info
))
5564 != (unsigned HOST_WIDE_INT
) vectorization_factor
)
5565 && dump_enabled_p ())
5566 dump_printf_loc (MSG_NOTE
, vect_location
, "multiple-types.");
5568 if (STMT_VINFO_DEF_TYPE (stmt_info
) == vect_induction_def
)
5570 if (dump_enabled_p ())
5571 dump_printf_loc (MSG_NOTE
, vect_location
, "transform phi.");
5572 vect_transform_stmt (phi
, NULL
, NULL
, NULL
, NULL
);
5576 pattern_stmt
= NULL
;
5577 for (si
= gsi_start_bb (bb
); !gsi_end_p (si
) || transform_pattern_stmt
;)
5581 if (transform_pattern_stmt
)
5582 stmt
= pattern_stmt
;
5584 stmt
= gsi_stmt (si
);
5586 if (dump_enabled_p ())
5588 dump_printf_loc (MSG_NOTE
, vect_location
,
5589 "------>vectorizing statement: ");
5590 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
, stmt
, 0);
5593 stmt_info
= vinfo_for_stmt (stmt
);
5595 /* vector stmts created in the outer-loop during vectorization of
5596 stmts in an inner-loop may not have a stmt_info, and do not
5597 need to be vectorized. */
5604 if (MAY_HAVE_DEBUG_STMTS
&& !STMT_VINFO_LIVE_P (stmt_info
))
5605 vect_loop_kill_debug_uses (loop
, stmt
);
5607 if (!STMT_VINFO_RELEVANT_P (stmt_info
)
5608 && !STMT_VINFO_LIVE_P (stmt_info
))
5610 if (STMT_VINFO_IN_PATTERN_P (stmt_info
)
5611 && (pattern_stmt
= STMT_VINFO_RELATED_STMT (stmt_info
))
5612 && (STMT_VINFO_RELEVANT_P (vinfo_for_stmt (pattern_stmt
))
5613 || STMT_VINFO_LIVE_P (vinfo_for_stmt (pattern_stmt
))))
5615 stmt
= pattern_stmt
;
5616 stmt_info
= vinfo_for_stmt (stmt
);
5624 else if (STMT_VINFO_IN_PATTERN_P (stmt_info
)
5625 && (pattern_stmt
= STMT_VINFO_RELATED_STMT (stmt_info
))
5626 && (STMT_VINFO_RELEVANT_P (vinfo_for_stmt (pattern_stmt
))
5627 || STMT_VINFO_LIVE_P (vinfo_for_stmt (pattern_stmt
))))
5628 transform_pattern_stmt
= true;
5630 /* If pattern statement has def stmts, vectorize them too. */
5631 if (is_pattern_stmt_p (stmt_info
))
5633 if (pattern_def_seq
== NULL
)
5635 pattern_def_seq
= STMT_VINFO_PATTERN_DEF_SEQ (stmt_info
);
5636 pattern_def_si
= gsi_start (pattern_def_seq
);
5638 else if (!gsi_end_p (pattern_def_si
))
5639 gsi_next (&pattern_def_si
);
5640 if (pattern_def_seq
!= NULL
)
5642 gimple pattern_def_stmt
= NULL
;
5643 stmt_vec_info pattern_def_stmt_info
= NULL
;
5645 while (!gsi_end_p (pattern_def_si
))
5647 pattern_def_stmt
= gsi_stmt (pattern_def_si
);
5648 pattern_def_stmt_info
5649 = vinfo_for_stmt (pattern_def_stmt
);
5650 if (STMT_VINFO_RELEVANT_P (pattern_def_stmt_info
)
5651 || STMT_VINFO_LIVE_P (pattern_def_stmt_info
))
5653 gsi_next (&pattern_def_si
);
5656 if (!gsi_end_p (pattern_def_si
))
5658 if (dump_enabled_p ())
5660 dump_printf_loc (MSG_NOTE
, vect_location
,
5661 "==> vectorizing pattern def "
5663 dump_gimple_stmt (MSG_NOTE
, TDF_SLIM
,
5664 pattern_def_stmt
, 0);
5667 stmt
= pattern_def_stmt
;
5668 stmt_info
= pattern_def_stmt_info
;
5672 pattern_def_si
= gsi_none ();
5673 transform_pattern_stmt
= false;
5677 transform_pattern_stmt
= false;
5680 gcc_assert (STMT_VINFO_VECTYPE (stmt_info
));
5681 nunits
= (unsigned int) TYPE_VECTOR_SUBPARTS (
5682 STMT_VINFO_VECTYPE (stmt_info
));
5683 if (!STMT_SLP_TYPE (stmt_info
)
5684 && nunits
!= (unsigned int) vectorization_factor
5685 && dump_enabled_p ())
5686 /* For SLP VF is set according to unrolling factor, and not to
5687 vector size, hence for SLP this print is not valid. */
5688 dump_printf_loc (MSG_NOTE
, vect_location
,
5691 /* SLP. Schedule all the SLP instances when the first SLP stmt is
5693 if (STMT_SLP_TYPE (stmt_info
))
5697 slp_scheduled
= true;
5699 if (dump_enabled_p ())
5700 dump_printf_loc (MSG_NOTE
, vect_location
,
5701 "=== scheduling SLP instances ===");
5703 vect_schedule_slp (loop_vinfo
, NULL
);
5706 /* Hybrid SLP stmts must be vectorized in addition to SLP. */
5707 if (!vinfo_for_stmt (stmt
) || PURE_SLP_STMT (stmt_info
))
5709 if (!transform_pattern_stmt
&& gsi_end_p (pattern_def_si
))
5711 pattern_def_seq
= NULL
;
5718 /* -------- vectorize statement ------------ */
5719 if (dump_enabled_p ())
5720 dump_printf_loc (MSG_NOTE
, vect_location
, "transform statement.");
5722 grouped_store
= false;
5723 is_store
= vect_transform_stmt (stmt
, &si
, &grouped_store
, NULL
, NULL
);
5726 if (STMT_VINFO_GROUPED_ACCESS (stmt_info
))
5728 /* Interleaving. If IS_STORE is TRUE, the vectorization of the
5729 interleaving chain was completed - free all the stores in
5732 vect_remove_stores (GROUP_FIRST_ELEMENT (stmt_info
));
5737 /* Free the attached stmt_vec_info and remove the stmt. */
5738 gimple store
= gsi_stmt (si
);
5739 free_stmt_vec_info (store
);
5740 unlink_stmt_vdef (store
);
5741 gsi_remove (&si
, true);
5742 release_defs (store
);
5747 if (!transform_pattern_stmt
&& gsi_end_p (pattern_def_si
))
5749 pattern_def_seq
= NULL
;
5755 slpeel_make_loop_iterate_ntimes (loop
, ratio
);
5757 /* Reduce loop iterations by the vectorization factor. */
5758 scale_loop_profile (loop
, RDIV (REG_BR_PROB_BASE
, vectorization_factor
),
5759 expected_iterations
/ vectorization_factor
);
5760 loop
->nb_iterations_upper_bound
5761 = loop
->nb_iterations_upper_bound
.udiv (double_int::from_uhwi (vectorization_factor
),
5763 if (LOOP_VINFO_PEELING_FOR_GAPS (loop_vinfo
)
5764 && loop
->nb_iterations_upper_bound
!= double_int_zero
)
5765 loop
->nb_iterations_upper_bound
= loop
->nb_iterations_upper_bound
- double_int_one
;
5766 if (loop
->any_estimate
)
5768 loop
->nb_iterations_estimate
5769 = loop
->nb_iterations_estimate
.udiv (double_int::from_uhwi (vectorization_factor
),
5771 if (LOOP_VINFO_PEELING_FOR_GAPS (loop_vinfo
)
5772 && loop
->nb_iterations_estimate
!= double_int_zero
)
5773 loop
->nb_iterations_estimate
= loop
->nb_iterations_estimate
- double_int_one
;
5776 if (dump_enabled_p ())
5777 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS
, vect_location
, "LOOP VECTORIZED.");
5778 if (loop
->inner
&& dump_enabled_p ())
5779 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS
, vect_location
,
5780 "OUTER LOOP VECTORIZED.");