diff options
Diffstat (limited to 'gcc/tree-vectorizer.c')
| -rw-r--r-- | gcc/tree-vectorizer.c | 2738 |
1 files changed, 68 insertions, 2670 deletions
diff --git a/gcc/tree-vectorizer.c b/gcc/tree-vectorizer.c index 2c5d9cc..0636c6a 100644 --- a/gcc/tree-vectorizer.c +++ b/gcc/tree-vectorizer.c @@ -1,7 +1,7 @@ -/* Loop Vectorization - Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Free Software +/* Vectorizer + Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc. - Contributed by Dorit Naishlos <dorit@il.ibm.com> + Contributed by Dorit Naishlos <dorit@il.ibm.com> This file is part of GCC. @@ -19,105 +19,40 @@ You should have received a copy of the GNU General Public License along with GCC; see the file COPYING3. If not see <http://www.gnu.org/licenses/>. */ -/* Loop Vectorization Pass. - - This pass tries to vectorize loops. This first implementation focuses on - simple inner-most loops, with no conditional control flow, and a set of - simple operations which vector form can be expressed using existing - tree codes (PLUS, MULT etc). - - For example, the vectorizer transforms the following simple loop: - - short a[N]; short b[N]; short c[N]; int i; - - for (i=0; i<N; i++){ - a[i] = b[i] + c[i]; - } - - as if it was manually vectorized by rewriting the source code into: - - typedef int __attribute__((mode(V8HI))) v8hi; - short a[N]; short b[N]; short c[N]; int i; - v8hi *pa = (v8hi*)a, *pb = (v8hi*)b, *pc = (v8hi*)c; - v8hi va, vb, vc; - - for (i=0; i<N/8; i++){ - vb = pb[i]; - vc = pc[i]; - va = vb + vc; - pa[i] = va; - } - - The main entry to this pass is vectorize_loops(), in which - the vectorizer applies a set of analyses on a given set of loops, - followed by the actual vectorization transformation for the loops that - had successfully passed the analysis phase. - - Throughout this pass we make a distinction between two types of - data: scalars (which are represented by SSA_NAMES), and memory references - ("data-refs"). These two types of data require different handling both - during analysis and transformation. The types of data-refs that the - vectorizer currently supports are ARRAY_REFS which base is an array DECL - (not a pointer), and INDIRECT_REFS through pointers; both array and pointer - accesses are required to have a simple (consecutive) access pattern. - - Analysis phase: - =============== - The driver for the analysis phase is vect_analyze_loop_nest(). - It applies a set of analyses, some of which rely on the scalar evolution - analyzer (scev) developed by Sebastian Pop. - - During the analysis phase the vectorizer records some information - per stmt in a "stmt_vec_info" struct which is attached to each stmt in the - loop, as well as general information about the loop as a whole, which is - recorded in a "loop_vec_info" struct attached to each loop. - - Transformation phase: - ===================== - The loop transformation phase scans all the stmts in the loop, and - creates a vector stmt (or a sequence of stmts) for each scalar stmt S in - the loop that needs to be vectorized. It insert the vector code sequence - just before the scalar stmt S, and records a pointer to the vector code - in STMT_VINFO_VEC_STMT (stmt_info) (stmt_info is the stmt_vec_info struct - attached to S). This pointer will be used for the vectorization of following - stmts which use the def of stmt S. Stmt S is removed if it writes to memory; - otherwise, we rely on dead code elimination for removing it. - - For example, say stmt S1 was vectorized into stmt VS1: - - VS1: vb = px[i]; - S1: b = x[i]; STMT_VINFO_VEC_STMT (stmt_info (S1)) = VS1 - S2: a = b; - - To vectorize stmt S2, the vectorizer first finds the stmt that defines - the operand 'b' (S1), and gets the relevant vector def 'vb' from the - vector stmt VS1 pointed to by STMT_VINFO_VEC_STMT (stmt_info (S1)). The - resulting sequence would be: - - VS1: vb = px[i]; - S1: b = x[i]; STMT_VINFO_VEC_STMT (stmt_info (S1)) = VS1 - VS2: va = vb; - S2: a = b; STMT_VINFO_VEC_STMT (stmt_info (S2)) = VS2 - - Operands that are not SSA_NAMEs, are data-refs that appear in - load/store operations (like 'x[i]' in S1), and are handled differently. - - Target modeling: - ================= - Currently the only target specific information that is used is the - size of the vector (in bytes) - "UNITS_PER_SIMD_WORD". Targets that can - support different sizes of vectors, for now will need to specify one value - for "UNITS_PER_SIMD_WORD". More flexibility will be added in the future. - - Since we only vectorize operations which vector form can be - expressed using existing tree codes, to verify that an operation is - supported, the vectorizer checks the relevant optab at the relevant - machine_mode (e.g, optab_handler (add_optab, V8HImode)->insn_code). If - the value found is CODE_FOR_nothing, then there's no target support, and - we can't vectorize the stmt. - - For additional information on this project see: - http://gcc.gnu.org/projects/tree-ssa/vectorization.html +/* Loop and basic block vectorizer. + + This file contains drivers for the three vectorizers: + (1) loop vectorizer (inter-iteration parallelism), + (2) loop-aware SLP (intra-iteration parallelism) (invoked by the loop + vectorizer) + (3) BB vectorizer (out-of-loops), aka SLP + + The rest of the vectorizer's code is organized as follows: + - tree-vect-loop.c - loop specific parts such as reductions, etc. These are + used by drivers (1) and (2). + - tree-vect-loop-manip.c - vectorizer's loop control-flow utilities, used by + drivers (1) and (2). + - tree-vect-slp.c - BB vectorization specific analysis and transformation, + used by drivers (2) and (3). + - tree-vect-stmts.c - statements analysis and transformation (used by all). + - tree-vect-data-refs.c - vectorizer specific data-refs analysis and + manipulations (used by all). + - tree-vect-patterns.c - vectorizable code patterns detector (used by all) + + Here's a poor attempt at illustrating that: + + tree-vectorizer.c: + loop_vect() loop_aware_slp() slp_vect() + | / \ / + | / \ / + tree-vect-loop.c tree-vect-slp.c + | \ \ / / | + | \ \/ / | + | \ /\ / | + | \ / \ / | + tree-vect-stmts.c tree-vect-data-refs.c + \ / + tree-vect-patterns.c */ #include "config.h" @@ -126,32 +61,13 @@ along with GCC; see the file COPYING3. If not see #include "tm.h" #include "ggc.h" #include "tree.h" -#include "target.h" -#include "rtl.h" -#include "basic-block.h" #include "diagnostic.h" #include "tree-flow.h" #include "tree-dump.h" -#include "timevar.h" #include "cfgloop.h" #include "cfglayout.h" -#include "expr.h" -#include "recog.h" -#include "optabs.h" -#include "params.h" -#include "toplev.h" -#include "tree-chrec.h" -#include "tree-data-ref.h" -#include "tree-scalar-evolution.h" -#include "input.h" -#include "hashtab.h" #include "tree-vectorizer.h" #include "tree-pass.h" -#include "langhooks.h" - -/************************************************************************* - General Vectorization Utilities - *************************************************************************/ /* vect_dump will be set to stderr or dump_file if exist. */ FILE *vect_dump; @@ -161,7 +77,7 @@ FILE *vect_dump; enum verbosity_levels vect_verbosity_level = MAX_VERBOSITY_LEVEL; /* Loop location. */ -static LOC vect_loop_location; +LOC vect_loop_location; /* Bitmap of virtual variables to be renamed. */ bitmap vect_memsyms_to_rename; @@ -170,1273 +86,6 @@ bitmap vect_memsyms_to_rename; VEC(vec_void_p,heap) *stmt_vec_info_vec; -/************************************************************************* - Simple Loop Peeling Utilities - - Utilities to support loop peeling for vectorization purposes. - *************************************************************************/ - - -/* Renames the use *OP_P. */ - -static void -rename_use_op (use_operand_p op_p) -{ - tree new_name; - - if (TREE_CODE (USE_FROM_PTR (op_p)) != SSA_NAME) - return; - - new_name = get_current_def (USE_FROM_PTR (op_p)); - - /* Something defined outside of the loop. */ - if (!new_name) - return; - - /* An ordinary ssa name defined in the loop. */ - - SET_USE (op_p, new_name); -} - - -/* Renames the variables in basic block BB. */ - -void -rename_variables_in_bb (basic_block bb) -{ - gimple_stmt_iterator gsi; - gimple stmt; - use_operand_p use_p; - ssa_op_iter iter; - edge e; - edge_iterator ei; - struct loop *loop = bb->loop_father; - - for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) - { - stmt = gsi_stmt (gsi); - FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_ALL_USES) - rename_use_op (use_p); - } - - FOR_EACH_EDGE (e, ei, bb->succs) - { - if (!flow_bb_inside_loop_p (loop, e->dest)) - continue; - for (gsi = gsi_start_phis (e->dest); !gsi_end_p (gsi); gsi_next (&gsi)) - rename_use_op (PHI_ARG_DEF_PTR_FROM_EDGE (gsi_stmt (gsi), e)); - } -} - - -/* Renames variables in new generated LOOP. */ - -void -rename_variables_in_loop (struct loop *loop) -{ - unsigned i; - basic_block *bbs; - - bbs = get_loop_body (loop); - - for (i = 0; i < loop->num_nodes; i++) - rename_variables_in_bb (bbs[i]); - - free (bbs); -} - - -/* Update the PHI nodes of NEW_LOOP. - - NEW_LOOP is a duplicate of ORIG_LOOP. - AFTER indicates whether NEW_LOOP executes before or after ORIG_LOOP: - AFTER is true if NEW_LOOP executes after ORIG_LOOP, and false if it - executes before it. */ - -static void -slpeel_update_phis_for_duplicate_loop (struct loop *orig_loop, - struct loop *new_loop, bool after) -{ - tree new_ssa_name; - gimple phi_new, phi_orig; - tree def; - edge orig_loop_latch = loop_latch_edge (orig_loop); - edge orig_entry_e = loop_preheader_edge (orig_loop); - edge new_loop_exit_e = single_exit (new_loop); - edge new_loop_entry_e = loop_preheader_edge (new_loop); - edge entry_arg_e = (after ? orig_loop_latch : orig_entry_e); - gimple_stmt_iterator gsi_new, gsi_orig; - - /* - step 1. For each loop-header-phi: - Add the first phi argument for the phi in NEW_LOOP - (the one associated with the entry of NEW_LOOP) - - step 2. For each loop-header-phi: - Add the second phi argument for the phi in NEW_LOOP - (the one associated with the latch of NEW_LOOP) - - step 3. Update the phis in the successor block of NEW_LOOP. - - case 1: NEW_LOOP was placed before ORIG_LOOP: - The successor block of NEW_LOOP is the header of ORIG_LOOP. - Updating the phis in the successor block can therefore be done - along with the scanning of the loop header phis, because the - header blocks of ORIG_LOOP and NEW_LOOP have exactly the same - phi nodes, organized in the same order. - - case 2: NEW_LOOP was placed after ORIG_LOOP: - The successor block of NEW_LOOP is the original exit block of - ORIG_LOOP - the phis to be updated are the loop-closed-ssa phis. - We postpone updating these phis to a later stage (when - loop guards are added). - */ - - - /* Scan the phis in the headers of the old and new loops - (they are organized in exactly the same order). */ - - for (gsi_new = gsi_start_phis (new_loop->header), - gsi_orig = gsi_start_phis (orig_loop->header); - !gsi_end_p (gsi_new) && !gsi_end_p (gsi_orig); - gsi_next (&gsi_new), gsi_next (&gsi_orig)) - { - phi_new = gsi_stmt (gsi_new); - phi_orig = gsi_stmt (gsi_orig); - - /* step 1. */ - def = PHI_ARG_DEF_FROM_EDGE (phi_orig, entry_arg_e); - add_phi_arg (phi_new, def, new_loop_entry_e); - - /* step 2. */ - def = PHI_ARG_DEF_FROM_EDGE (phi_orig, orig_loop_latch); - if (TREE_CODE (def) != SSA_NAME) - continue; - - new_ssa_name = get_current_def (def); - if (!new_ssa_name) - { - /* This only happens if there are no definitions - inside the loop. use the phi_result in this case. */ - new_ssa_name = PHI_RESULT (phi_new); - } - - /* An ordinary ssa name defined in the loop. */ - add_phi_arg (phi_new, new_ssa_name, loop_latch_edge (new_loop)); - - /* step 3 (case 1). */ - if (!after) - { - gcc_assert (new_loop_exit_e == orig_entry_e); - SET_PHI_ARG_DEF (phi_orig, - new_loop_exit_e->dest_idx, - new_ssa_name); - } - } -} - - -/* Update PHI nodes for a guard of the LOOP. - - Input: - - LOOP, GUARD_EDGE: LOOP is a loop for which we added guard code that - controls whether LOOP is to be executed. GUARD_EDGE is the edge that - originates from the guard-bb, skips LOOP and reaches the (unique) exit - bb of LOOP. This loop-exit-bb is an empty bb with one successor. - We denote this bb NEW_MERGE_BB because before the guard code was added - it had a single predecessor (the LOOP header), and now it became a merge - point of two paths - the path that ends with the LOOP exit-edge, and - the path that ends with GUARD_EDGE. - - NEW_EXIT_BB: New basic block that is added by this function between LOOP - and NEW_MERGE_BB. It is used to place loop-closed-ssa-form exit-phis. - - ===> The CFG before the guard-code was added: - LOOP_header_bb: - loop_body - if (exit_loop) goto update_bb - else goto LOOP_header_bb - update_bb: - - ==> The CFG after the guard-code was added: - guard_bb: - if (LOOP_guard_condition) goto new_merge_bb - else goto LOOP_header_bb - LOOP_header_bb: - loop_body - if (exit_loop_condition) goto new_merge_bb - else goto LOOP_header_bb - new_merge_bb: - goto update_bb - update_bb: - - ==> The CFG after this function: - guard_bb: - if (LOOP_guard_condition) goto new_merge_bb - else goto LOOP_header_bb - LOOP_header_bb: - loop_body - if (exit_loop_condition) goto new_exit_bb - else goto LOOP_header_bb - new_exit_bb: - new_merge_bb: - goto update_bb - update_bb: - - This function: - 1. creates and updates the relevant phi nodes to account for the new - incoming edge (GUARD_EDGE) into NEW_MERGE_BB. This involves: - 1.1. Create phi nodes at NEW_MERGE_BB. - 1.2. Update the phi nodes at the successor of NEW_MERGE_BB (denoted - UPDATE_BB). UPDATE_BB was the exit-bb of LOOP before NEW_MERGE_BB - 2. preserves loop-closed-ssa-form by creating the required phi nodes - at the exit of LOOP (i.e, in NEW_EXIT_BB). - - There are two flavors to this function: - - slpeel_update_phi_nodes_for_guard1: - Here the guard controls whether we enter or skip LOOP, where LOOP is a - prolog_loop (loop1 below), and the new phis created in NEW_MERGE_BB are - for variables that have phis in the loop header. - - slpeel_update_phi_nodes_for_guard2: - Here the guard controls whether we enter or skip LOOP, where LOOP is an - epilog_loop (loop2 below), and the new phis created in NEW_MERGE_BB are - for variables that have phis in the loop exit. - - I.E., the overall structure is: - - loop1_preheader_bb: - guard1 (goto loop1/merge1_bb) - loop1 - loop1_exit_bb: - guard2 (goto merge1_bb/merge2_bb) - merge1_bb - loop2 - loop2_exit_bb - merge2_bb - next_bb - - slpeel_update_phi_nodes_for_guard1 takes care of creating phis in - loop1_exit_bb and merge1_bb. These are entry phis (phis for the vars - that have phis in loop1->header). - - slpeel_update_phi_nodes_for_guard2 takes care of creating phis in - loop2_exit_bb and merge2_bb. These are exit phis (phis for the vars - that have phis in next_bb). It also adds some of these phis to - loop1_exit_bb. - - slpeel_update_phi_nodes_for_guard1 is always called before - slpeel_update_phi_nodes_for_guard2. They are both needed in order - to create correct data-flow and loop-closed-ssa-form. - - Generally slpeel_update_phi_nodes_for_guard1 creates phis for variables - that change between iterations of a loop (and therefore have a phi-node - at the loop entry), whereas slpeel_update_phi_nodes_for_guard2 creates - phis for variables that are used out of the loop (and therefore have - loop-closed exit phis). Some variables may be both updated between - iterations and used after the loop. This is why in loop1_exit_bb we - may need both entry_phis (created by slpeel_update_phi_nodes_for_guard1) - and exit phis (created by slpeel_update_phi_nodes_for_guard2). - - - IS_NEW_LOOP: if IS_NEW_LOOP is true, then LOOP is a newly created copy of - an original loop. i.e., we have: - - orig_loop - guard_bb (goto LOOP/new_merge) - new_loop <-- LOOP - new_exit - new_merge - next_bb - - If IS_NEW_LOOP is false, then LOOP is an original loop, in which case we - have: - - new_loop - guard_bb (goto LOOP/new_merge) - orig_loop <-- LOOP - new_exit - new_merge - next_bb - - The SSA names defined in the original loop have a current - reaching definition that that records the corresponding new - ssa-name used in the new duplicated loop copy. - */ - -/* Function slpeel_update_phi_nodes_for_guard1 - - Input: - - GUARD_EDGE, LOOP, IS_NEW_LOOP, NEW_EXIT_BB - as explained above. - - DEFS - a bitmap of ssa names to mark new names for which we recorded - information. - - In the context of the overall structure, we have: - - loop1_preheader_bb: - guard1 (goto loop1/merge1_bb) -LOOP-> loop1 - loop1_exit_bb: - guard2 (goto merge1_bb/merge2_bb) - merge1_bb - loop2 - loop2_exit_bb - merge2_bb - next_bb - - For each name updated between loop iterations (i.e - for each name that has - an entry (loop-header) phi in LOOP) we create a new phi in: - 1. merge1_bb (to account for the edge from guard1) - 2. loop1_exit_bb (an exit-phi to keep LOOP in loop-closed form) -*/ - -static void -slpeel_update_phi_nodes_for_guard1 (edge guard_edge, struct loop *loop, - bool is_new_loop, basic_block *new_exit_bb, - bitmap *defs) -{ - gimple orig_phi, new_phi; - gimple update_phi, update_phi2; - tree guard_arg, loop_arg; - basic_block new_merge_bb = guard_edge->dest; - edge e = EDGE_SUCC (new_merge_bb, 0); - basic_block update_bb = e->dest; - basic_block orig_bb = loop->header; - edge new_exit_e; - tree current_new_name; - tree name; - gimple_stmt_iterator gsi_orig, gsi_update; - - /* Create new bb between loop and new_merge_bb. */ - *new_exit_bb = split_edge (single_exit (loop)); - - new_exit_e = EDGE_SUCC (*new_exit_bb, 0); - - for (gsi_orig = gsi_start_phis (orig_bb), - gsi_update = gsi_start_phis (update_bb); - !gsi_end_p (gsi_orig) && !gsi_end_p (gsi_update); - gsi_next (&gsi_orig), gsi_next (&gsi_update)) - { - orig_phi = gsi_stmt (gsi_orig); - update_phi = gsi_stmt (gsi_update); - - /* Virtual phi; Mark it for renaming. We actually want to call - mar_sym_for_renaming, but since all ssa renaming datastructures - are going to be freed before we get to call ssa_update, we just - record this name for now in a bitmap, and will mark it for - renaming later. */ - name = PHI_RESULT (orig_phi); - if (!is_gimple_reg (SSA_NAME_VAR (name))) - bitmap_set_bit (vect_memsyms_to_rename, DECL_UID (SSA_NAME_VAR (name))); - - /** 1. Handle new-merge-point phis **/ - - /* 1.1. Generate new phi node in NEW_MERGE_BB: */ - new_phi = create_phi_node (SSA_NAME_VAR (PHI_RESULT (orig_phi)), - new_merge_bb); - - /* 1.2. NEW_MERGE_BB has two incoming edges: GUARD_EDGE and the exit-edge - of LOOP. Set the two phi args in NEW_PHI for these edges: */ - loop_arg = PHI_ARG_DEF_FROM_EDGE (orig_phi, EDGE_SUCC (loop->latch, 0)); - guard_arg = PHI_ARG_DEF_FROM_EDGE (orig_phi, loop_preheader_edge (loop)); - - add_phi_arg (new_phi, loop_arg, new_exit_e); - add_phi_arg (new_phi, guard_arg, guard_edge); - - /* 1.3. Update phi in successor block. */ - gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi, e) == loop_arg - || PHI_ARG_DEF_FROM_EDGE (update_phi, e) == guard_arg); - SET_PHI_ARG_DEF (update_phi, e->dest_idx, PHI_RESULT (new_phi)); - update_phi2 = new_phi; - - - /** 2. Handle loop-closed-ssa-form phis **/ - - if (!is_gimple_reg (PHI_RESULT (orig_phi))) - continue; - - /* 2.1. Generate new phi node in NEW_EXIT_BB: */ - new_phi = create_phi_node (SSA_NAME_VAR (PHI_RESULT (orig_phi)), - *new_exit_bb); - - /* 2.2. NEW_EXIT_BB has one incoming edge: the exit-edge of the loop. */ - add_phi_arg (new_phi, loop_arg, single_exit (loop)); - - /* 2.3. Update phi in successor of NEW_EXIT_BB: */ - gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi2, new_exit_e) == loop_arg); - SET_PHI_ARG_DEF (update_phi2, new_exit_e->dest_idx, PHI_RESULT (new_phi)); - - /* 2.4. Record the newly created name with set_current_def. - We want to find a name such that - name = get_current_def (orig_loop_name) - and to set its current definition as follows: - set_current_def (name, new_phi_name) - - If LOOP is a new loop then loop_arg is already the name we're - looking for. If LOOP is the original loop, then loop_arg is - the orig_loop_name and the relevant name is recorded in its - current reaching definition. */ - if (is_new_loop) - current_new_name = loop_arg; - else - { - current_new_name = get_current_def (loop_arg); - /* current_def is not available only if the variable does not - change inside the loop, in which case we also don't care - about recording a current_def for it because we won't be - trying to create loop-exit-phis for it. */ - if (!current_new_name) - continue; - } - gcc_assert (get_current_def (current_new_name) == NULL_TREE); - - set_current_def (current_new_name, PHI_RESULT (new_phi)); - bitmap_set_bit (*defs, SSA_NAME_VERSION (current_new_name)); - } -} - - -/* Function slpeel_update_phi_nodes_for_guard2 - - Input: - - GUARD_EDGE, LOOP, IS_NEW_LOOP, NEW_EXIT_BB - as explained above. - - In the context of the overall structure, we have: - - loop1_preheader_bb: - guard1 (goto loop1/merge1_bb) - loop1 - loop1_exit_bb: - guard2 (goto merge1_bb/merge2_bb) - merge1_bb -LOOP-> loop2 - loop2_exit_bb - merge2_bb - next_bb - - For each name used out side the loop (i.e - for each name that has an exit - phi in next_bb) we create a new phi in: - 1. merge2_bb (to account for the edge from guard_bb) - 2. loop2_exit_bb (an exit-phi to keep LOOP in loop-closed form) - 3. guard2 bb (an exit phi to keep the preceding loop in loop-closed form), - if needed (if it wasn't handled by slpeel_update_phis_nodes_for_phi1). -*/ - -static void -slpeel_update_phi_nodes_for_guard2 (edge guard_edge, struct loop *loop, - bool is_new_loop, basic_block *new_exit_bb) -{ - gimple orig_phi, new_phi; - gimple update_phi, update_phi2; - tree guard_arg, loop_arg; - basic_block new_merge_bb = guard_edge->dest; - edge e = EDGE_SUCC (new_merge_bb, 0); - basic_block update_bb = e->dest; - edge new_exit_e; - tree orig_def, orig_def_new_name; - tree new_name, new_name2; - tree arg; - gimple_stmt_iterator gsi; - - /* Create new bb between loop and new_merge_bb. */ - *new_exit_bb = split_edge (single_exit (loop)); - - new_exit_e = EDGE_SUCC (*new_exit_bb, 0); - - for (gsi = gsi_start_phis (update_bb); !gsi_end_p (gsi); gsi_next (&gsi)) - { - update_phi = gsi_stmt (gsi); - orig_phi = update_phi; - orig_def = PHI_ARG_DEF_FROM_EDGE (orig_phi, e); - /* This loop-closed-phi actually doesn't represent a use - out of the loop - the phi arg is a constant. */ - if (TREE_CODE (orig_def) != SSA_NAME) - continue; - orig_def_new_name = get_current_def (orig_def); - arg = NULL_TREE; - - /** 1. Handle new-merge-point phis **/ - - /* 1.1. Generate new phi node in NEW_MERGE_BB: */ - new_phi = create_phi_node (SSA_NAME_VAR (PHI_RESULT (orig_phi)), - new_merge_bb); - - /* 1.2. NEW_MERGE_BB has two incoming edges: GUARD_EDGE and the exit-edge - of LOOP. Set the two PHI args in NEW_PHI for these edges: */ - new_name = orig_def; - new_name2 = NULL_TREE; - if (orig_def_new_name) - { - new_name = orig_def_new_name; - /* Some variables have both loop-entry-phis and loop-exit-phis. - Such variables were given yet newer names by phis placed in - guard_bb by slpeel_update_phi_nodes_for_guard1. I.e: - new_name2 = get_current_def (get_current_def (orig_name)). */ - new_name2 = get_current_def (new_name); - } - - if (is_new_loop) - { - guard_arg = orig_def; - loop_arg = new_name; - } - else - { - guard_arg = new_name; - loop_arg = orig_def; - } - if (new_name2) - guard_arg = new_name2; - - add_phi_arg (new_phi, loop_arg, new_exit_e); - add_phi_arg (new_phi, guard_arg, guard_edge); - - /* 1.3. Update phi in successor block. */ - gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi, e) == orig_def); - SET_PHI_ARG_DEF (update_phi, e->dest_idx, PHI_RESULT (new_phi)); - update_phi2 = new_phi; - - - /** 2. Handle loop-closed-ssa-form phis **/ - - /* 2.1. Generate new phi node in NEW_EXIT_BB: */ - new_phi = create_phi_node (SSA_NAME_VAR (PHI_RESULT (orig_phi)), - *new_exit_bb); - - /* 2.2. NEW_EXIT_BB has one incoming edge: the exit-edge of the loop. */ - add_phi_arg (new_phi, loop_arg, single_exit (loop)); - - /* 2.3. Update phi in successor of NEW_EXIT_BB: */ - gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi2, new_exit_e) == loop_arg); - SET_PHI_ARG_DEF (update_phi2, new_exit_e->dest_idx, PHI_RESULT (new_phi)); - - - /** 3. Handle loop-closed-ssa-form phis for first loop **/ - - /* 3.1. Find the relevant names that need an exit-phi in - GUARD_BB, i.e. names for which - slpeel_update_phi_nodes_for_guard1 had not already created a - phi node. This is the case for names that are used outside - the loop (and therefore need an exit phi) but are not updated - across loop iterations (and therefore don't have a - loop-header-phi). - - slpeel_update_phi_nodes_for_guard1 is responsible for - creating loop-exit phis in GUARD_BB for names that have a - loop-header-phi. When such a phi is created we also record - the new name in its current definition. If this new name - exists, then guard_arg was set to this new name (see 1.2 - above). Therefore, if guard_arg is not this new name, this - is an indication that an exit-phi in GUARD_BB was not yet - created, so we take care of it here. */ - if (guard_arg == new_name2) - continue; - arg = guard_arg; - - /* 3.2. Generate new phi node in GUARD_BB: */ - new_phi = create_phi_node (SSA_NAME_VAR (PHI_RESULT (orig_phi)), - guard_edge->src); - - /* 3.3. GUARD_BB has one incoming edge: */ - gcc_assert (EDGE_COUNT (guard_edge->src->preds) == 1); - add_phi_arg (new_phi, arg, EDGE_PRED (guard_edge->src, 0)); - - /* 3.4. Update phi in successor of GUARD_BB: */ - gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi2, guard_edge) - == guard_arg); - SET_PHI_ARG_DEF (update_phi2, guard_edge->dest_idx, PHI_RESULT (new_phi)); - } -} - - -/* Make the LOOP iterate NITERS times. This is done by adding a new IV - that starts at zero, increases by one and its limit is NITERS. - - Assumption: the exit-condition of LOOP is the last stmt in the loop. */ - -void -slpeel_make_loop_iterate_ntimes (struct loop *loop, tree niters) -{ - tree indx_before_incr, indx_after_incr; - gimple cond_stmt; - gimple orig_cond; - edge exit_edge = single_exit (loop); - gimple_stmt_iterator loop_cond_gsi; - gimple_stmt_iterator incr_gsi; - bool insert_after; - tree init = build_int_cst (TREE_TYPE (niters), 0); - tree step = build_int_cst (TREE_TYPE (niters), 1); - LOC loop_loc; - enum tree_code code; - - orig_cond = get_loop_exit_condition (loop); - gcc_assert (orig_cond); - loop_cond_gsi = gsi_for_stmt (orig_cond); - - standard_iv_increment_position (loop, &incr_gsi, &insert_after); - create_iv (init, step, NULL_TREE, loop, - &incr_gsi, insert_after, &indx_before_incr, &indx_after_incr); - - indx_after_incr = force_gimple_operand_gsi (&loop_cond_gsi, indx_after_incr, - true, NULL_TREE, true, - GSI_SAME_STMT); - niters = force_gimple_operand_gsi (&loop_cond_gsi, niters, true, NULL_TREE, - true, GSI_SAME_STMT); - - code = (exit_edge->flags & EDGE_TRUE_VALUE) ? GE_EXPR : LT_EXPR; - cond_stmt = gimple_build_cond (code, indx_after_incr, niters, NULL_TREE, - NULL_TREE); - - gsi_insert_before (&loop_cond_gsi, cond_stmt, GSI_SAME_STMT); - - /* Remove old loop exit test: */ - gsi_remove (&loop_cond_gsi, true); - - loop_loc = find_loop_location (loop); - if (dump_file && (dump_flags & TDF_DETAILS)) - { - if (loop_loc != UNKNOWN_LOC) - fprintf (dump_file, "\nloop at %s:%d: ", - LOC_FILE (loop_loc), LOC_LINE (loop_loc)); - print_gimple_stmt (dump_file, cond_stmt, 0, TDF_SLIM); - } - - loop->nb_iterations = niters; -} - - -/* Given LOOP this function generates a new copy of it and puts it - on E which is either the entry or exit of LOOP. */ - -struct loop * -slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *loop, edge e) -{ - struct loop *new_loop; - basic_block *new_bbs, *bbs; - bool at_exit; - bool was_imm_dom; - basic_block exit_dest; - gimple phi; - tree phi_arg; - edge exit, new_exit; - gimple_stmt_iterator gsi; - - at_exit = (e == single_exit (loop)); - if (!at_exit && e != loop_preheader_edge (loop)) - return NULL; - - bbs = get_loop_body (loop); - - /* Check whether duplication is possible. */ - if (!can_copy_bbs_p (bbs, loop->num_nodes)) - { - free (bbs); - return NULL; - } - - /* Generate new loop structure. */ - new_loop = duplicate_loop (loop, loop_outer (loop)); - if (!new_loop) - { - free (bbs); - return NULL; - } - - exit_dest = single_exit (loop)->dest; - was_imm_dom = (get_immediate_dominator (CDI_DOMINATORS, - exit_dest) == loop->header ? - true : false); - - new_bbs = XNEWVEC (basic_block, loop->num_nodes); - - exit = single_exit (loop); - copy_bbs (bbs, loop->num_nodes, new_bbs, - &exit, 1, &new_exit, NULL, - e->src); - - /* Duplicating phi args at exit bbs as coming - also from exit of duplicated loop. */ - for (gsi = gsi_start_phis (exit_dest); !gsi_end_p (gsi); gsi_next (&gsi)) - { - phi = gsi_stmt (gsi); - phi_arg = PHI_ARG_DEF_FROM_EDGE (phi, single_exit (loop)); - if (phi_arg) - { - edge new_loop_exit_edge; - - if (EDGE_SUCC (new_loop->header, 0)->dest == new_loop->latch) - new_loop_exit_edge = EDGE_SUCC (new_loop->header, 1); - else - new_loop_exit_edge = EDGE_SUCC (new_loop->header, 0); - - add_phi_arg (phi, phi_arg, new_loop_exit_edge); - } - } - - if (at_exit) /* Add the loop copy at exit. */ - { - redirect_edge_and_branch_force (e, new_loop->header); - PENDING_STMT (e) = NULL; - set_immediate_dominator (CDI_DOMINATORS, new_loop->header, e->src); - if (was_imm_dom) - set_immediate_dominator (CDI_DOMINATORS, exit_dest, new_loop->header); - } - else /* Add the copy at entry. */ - { - edge new_exit_e; - edge entry_e = loop_preheader_edge (loop); - basic_block preheader = entry_e->src; - - if (!flow_bb_inside_loop_p (new_loop, - EDGE_SUCC (new_loop->header, 0)->dest)) - new_exit_e = EDGE_SUCC (new_loop->header, 0); - else - new_exit_e = EDGE_SUCC (new_loop->header, 1); - - redirect_edge_and_branch_force (new_exit_e, loop->header); - PENDING_STMT (new_exit_e) = NULL; - set_immediate_dominator (CDI_DOMINATORS, loop->header, - new_exit_e->src); - - /* We have to add phi args to the loop->header here as coming - from new_exit_e edge. */ - for (gsi = gsi_start_phis (loop->header); - !gsi_end_p (gsi); - gsi_next (&gsi)) - { - phi = gsi_stmt (gsi); - phi_arg = PHI_ARG_DEF_FROM_EDGE (phi, entry_e); - if (phi_arg) - add_phi_arg (phi, phi_arg, new_exit_e); - } - - redirect_edge_and_branch_force (entry_e, new_loop->header); - PENDING_STMT (entry_e) = NULL; - set_immediate_dominator (CDI_DOMINATORS, new_loop->header, preheader); - } - - free (new_bbs); - free (bbs); - - return new_loop; -} - - -/* Given the condition statement COND, put it as the last statement - of GUARD_BB; EXIT_BB is the basic block to skip the loop; - Assumes that this is the single exit of the guarded loop. - Returns the skip edge. */ - -static edge -slpeel_add_loop_guard (basic_block guard_bb, tree cond, basic_block exit_bb, - basic_block dom_bb) -{ - gimple_stmt_iterator gsi; - edge new_e, enter_e; - gimple cond_stmt; - gimple_seq gimplify_stmt_list = NULL; - - enter_e = EDGE_SUCC (guard_bb, 0); - enter_e->flags &= ~EDGE_FALLTHRU; - enter_e->flags |= EDGE_FALSE_VALUE; - gsi = gsi_last_bb (guard_bb); - - cond = force_gimple_operand (cond, &gimplify_stmt_list, true, NULL_TREE); - cond_stmt = gimple_build_cond (NE_EXPR, - cond, build_int_cst (TREE_TYPE (cond), 0), - NULL_TREE, NULL_TREE); - if (gimplify_stmt_list) - gsi_insert_seq_after (&gsi, gimplify_stmt_list, GSI_NEW_STMT); - - gsi = gsi_last_bb (guard_bb); - gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT); - - /* Add new edge to connect guard block to the merge/loop-exit block. */ - new_e = make_edge (guard_bb, exit_bb, EDGE_TRUE_VALUE); - set_immediate_dominator (CDI_DOMINATORS, exit_bb, dom_bb); - return new_e; -} - - -/* This function verifies that the following restrictions apply to LOOP: - (1) it is innermost - (2) it consists of exactly 2 basic blocks - header, and an empty latch. - (3) it is single entry, single exit - (4) its exit condition is the last stmt in the header - (5) E is the entry/exit edge of LOOP. - */ - -bool -slpeel_can_duplicate_loop_p (const struct loop *loop, const_edge e) -{ - edge exit_e = single_exit (loop); - edge entry_e = loop_preheader_edge (loop); - gimple orig_cond = get_loop_exit_condition (loop); - gimple_stmt_iterator loop_exit_gsi = gsi_last_bb (exit_e->src); - - if (need_ssa_update_p ()) - return false; - - if (loop->inner - /* All loops have an outer scope; the only case loop->outer is NULL is for - the function itself. */ - || !loop_outer (loop) - || loop->num_nodes != 2 - || !empty_block_p (loop->latch) - || !single_exit (loop) - /* Verify that new loop exit condition can be trivially modified. */ - || (!orig_cond || orig_cond != gsi_stmt (loop_exit_gsi)) - || (e != exit_e && e != entry_e)) - return false; - - return true; -} - -#ifdef ENABLE_CHECKING -void -slpeel_verify_cfg_after_peeling (struct loop *first_loop, - struct loop *second_loop) -{ - basic_block loop1_exit_bb = single_exit (first_loop)->dest; - basic_block loop2_entry_bb = loop_preheader_edge (second_loop)->src; - basic_block loop1_entry_bb = loop_preheader_edge (first_loop)->src; - - /* A guard that controls whether the second_loop is to be executed or skipped - is placed in first_loop->exit. first_loop->exit therefore has two - successors - one is the preheader of second_loop, and the other is a bb - after second_loop. - */ - gcc_assert (EDGE_COUNT (loop1_exit_bb->succs) == 2); - - /* 1. Verify that one of the successors of first_loop->exit is the preheader - of second_loop. */ - - /* The preheader of new_loop is expected to have two predecessors: - first_loop->exit and the block that precedes first_loop. */ - - gcc_assert (EDGE_COUNT (loop2_entry_bb->preds) == 2 - && ((EDGE_PRED (loop2_entry_bb, 0)->src == loop1_exit_bb - && EDGE_PRED (loop2_entry_bb, 1)->src == loop1_entry_bb) - || (EDGE_PRED (loop2_entry_bb, 1)->src == loop1_exit_bb - && EDGE_PRED (loop2_entry_bb, 0)->src == loop1_entry_bb))); - - /* Verify that the other successor of first_loop->exit is after the - second_loop. */ - /* TODO */ -} -#endif - -/* If the run time cost model check determines that vectorization is - not profitable and hence scalar loop should be generated then set - FIRST_NITERS to prologue peeled iterations. This will allow all the - iterations to be executed in the prologue peeled scalar loop. */ - -void -set_prologue_iterations (basic_block bb_before_first_loop, - tree first_niters, - struct loop *loop, - unsigned int th) -{ - edge e; - basic_block cond_bb, then_bb; - tree var, prologue_after_cost_adjust_name; - gimple_stmt_iterator gsi; - gimple newphi; - edge e_true, e_false, e_fallthru; - gimple cond_stmt; - gimple_seq gimplify_stmt_list = NULL, stmts = NULL; - tree cost_pre_condition = NULL_TREE; - tree scalar_loop_iters = - unshare_expr (LOOP_VINFO_NITERS_UNCHANGED (loop_vec_info_for_loop (loop))); - - e = single_pred_edge (bb_before_first_loop); - cond_bb = split_edge(e); - - e = single_pred_edge (bb_before_first_loop); - then_bb = split_edge(e); - set_immediate_dominator (CDI_DOMINATORS, then_bb, cond_bb); - - e_false = make_single_succ_edge (cond_bb, bb_before_first_loop, - EDGE_FALSE_VALUE); - set_immediate_dominator (CDI_DOMINATORS, bb_before_first_loop, cond_bb); - - e_true = EDGE_PRED (then_bb, 0); - e_true->flags &= ~EDGE_FALLTHRU; - e_true->flags |= EDGE_TRUE_VALUE; - - e_fallthru = EDGE_SUCC (then_bb, 0); - - cost_pre_condition = - fold_build2 (LE_EXPR, boolean_type_node, scalar_loop_iters, - build_int_cst (TREE_TYPE (scalar_loop_iters), th)); - cost_pre_condition = - force_gimple_operand (cost_pre_condition, &gimplify_stmt_list, - true, NULL_TREE); - cond_stmt = gimple_build_cond (NE_EXPR, cost_pre_condition, - build_int_cst (TREE_TYPE (cost_pre_condition), - 0), NULL_TREE, NULL_TREE); - - gsi = gsi_last_bb (cond_bb); - if (gimplify_stmt_list) - gsi_insert_seq_after (&gsi, gimplify_stmt_list, GSI_NEW_STMT); - - gsi = gsi_last_bb (cond_bb); - gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT); - - var = create_tmp_var (TREE_TYPE (scalar_loop_iters), - "prologue_after_cost_adjust"); - add_referenced_var (var); - prologue_after_cost_adjust_name = - force_gimple_operand (scalar_loop_iters, &stmts, false, var); - - gsi = gsi_last_bb (then_bb); - if (stmts) - gsi_insert_seq_after (&gsi, stmts, GSI_NEW_STMT); - - newphi = create_phi_node (var, bb_before_first_loop); - add_phi_arg (newphi, prologue_after_cost_adjust_name, e_fallthru); - add_phi_arg (newphi, first_niters, e_false); - - first_niters = PHI_RESULT (newphi); -} - - -/* Function slpeel_tree_peel_loop_to_edge. - - Peel the first (last) iterations of LOOP into a new prolog (epilog) loop - that is placed on the entry (exit) edge E of LOOP. After this transformation - we have two loops one after the other - first-loop iterates FIRST_NITERS - times, and second-loop iterates the remainder NITERS - FIRST_NITERS times. - If the cost model indicates that it is profitable to emit a scalar - loop instead of the vector one, then the prolog (epilog) loop will iterate - for the entire unchanged scalar iterations of the loop. - - Input: - - LOOP: the loop to be peeled. - - E: the exit or entry edge of LOOP. - If it is the entry edge, we peel the first iterations of LOOP. In this - case first-loop is LOOP, and second-loop is the newly created loop. - If it is the exit edge, we peel the last iterations of LOOP. In this - case, first-loop is the newly created loop, and second-loop is LOOP. - - NITERS: the number of iterations that LOOP iterates. - - FIRST_NITERS: the number of iterations that the first-loop should iterate. - - UPDATE_FIRST_LOOP_COUNT: specified whether this function is responsible - for updating the loop bound of the first-loop to FIRST_NITERS. If it - is false, the caller of this function may want to take care of this - (this can be useful if we don't want new stmts added to first-loop). - - TH: cost model profitability threshold of iterations for vectorization. - - CHECK_PROFITABILITY: specify whether cost model check has not occurred - during versioning and hence needs to occur during - prologue generation or whether cost model check - has not occurred during prologue generation and hence - needs to occur during epilogue generation. - - - Output: - The function returns a pointer to the new loop-copy, or NULL if it failed - to perform the transformation. - - The function generates two if-then-else guards: one before the first loop, - and the other before the second loop: - The first guard is: - if (FIRST_NITERS == 0) then skip the first loop, - and go directly to the second loop. - The second guard is: - if (FIRST_NITERS == NITERS) then skip the second loop. - - FORNOW only simple loops are supported (see slpeel_can_duplicate_loop_p). - FORNOW the resulting code will not be in loop-closed-ssa form. -*/ - -struct loop* -slpeel_tree_peel_loop_to_edge (struct loop *loop, - edge e, tree first_niters, - tree niters, bool update_first_loop_count, - unsigned int th, bool check_profitability) -{ - struct loop *new_loop = NULL, *first_loop, *second_loop; - edge skip_e; - tree pre_condition = NULL_TREE; - bitmap definitions; - basic_block bb_before_second_loop, bb_after_second_loop; - basic_block bb_before_first_loop; - basic_block bb_between_loops; - basic_block new_exit_bb; - edge exit_e = single_exit (loop); - LOC loop_loc; - tree cost_pre_condition = NULL_TREE; - - if (!slpeel_can_duplicate_loop_p (loop, e)) - return NULL; - - /* We have to initialize cfg_hooks. Then, when calling - cfg_hooks->split_edge, the function tree_split_edge - is actually called and, when calling cfg_hooks->duplicate_block, - the function tree_duplicate_bb is called. */ - gimple_register_cfg_hooks (); - - - /* 1. Generate a copy of LOOP and put it on E (E is the entry/exit of LOOP). - Resulting CFG would be: - - first_loop: - do { - } while ... - - second_loop: - do { - } while ... - - orig_exit_bb: - */ - - if (!(new_loop = slpeel_tree_duplicate_loop_to_edge_cfg (loop, e))) - { - loop_loc = find_loop_location (loop); - if (dump_file && (dump_flags & TDF_DETAILS)) - { - if (loop_loc != UNKNOWN_LOC) - fprintf (dump_file, "\n%s:%d: note: ", - LOC_FILE (loop_loc), LOC_LINE (loop_loc)); - fprintf (dump_file, "tree_duplicate_loop_to_edge_cfg failed.\n"); - } - return NULL; - } - - if (e == exit_e) - { - /* NEW_LOOP was placed after LOOP. */ - first_loop = loop; - second_loop = new_loop; - } - else - { - /* NEW_LOOP was placed before LOOP. */ - first_loop = new_loop; - second_loop = loop; - } - - definitions = ssa_names_to_replace (); - slpeel_update_phis_for_duplicate_loop (loop, new_loop, e == exit_e); - rename_variables_in_loop (new_loop); - - - /* 2. Add the guard code in one of the following ways: - - 2.a Add the guard that controls whether the first loop is executed. - This occurs when this function is invoked for prologue or epilogue - generation and when the cost model check can be done at compile time. - - Resulting CFG would be: - - bb_before_first_loop: - if (FIRST_NITERS == 0) GOTO bb_before_second_loop - GOTO first-loop - - first_loop: - do { - } while ... - - bb_before_second_loop: - - second_loop: - do { - } while ... - - orig_exit_bb: - - 2.b Add the cost model check that allows the prologue - to iterate for the entire unchanged scalar - iterations of the loop in the event that the cost - model indicates that the scalar loop is more - profitable than the vector one. This occurs when - this function is invoked for prologue generation - and the cost model check needs to be done at run - time. - - Resulting CFG after prologue peeling would be: - - if (scalar_loop_iterations <= th) - FIRST_NITERS = scalar_loop_iterations - - bb_before_first_loop: - if (FIRST_NITERS == 0) GOTO bb_before_second_loop - GOTO first-loop - - first_loop: - do { - } while ... - - bb_before_second_loop: - - second_loop: - do { - } while ... - - orig_exit_bb: - - 2.c Add the cost model check that allows the epilogue - to iterate for the entire unchanged scalar - iterations of the loop in the event that the cost - model indicates that the scalar loop is more - profitable than the vector one. This occurs when - this function is invoked for epilogue generation - and the cost model check needs to be done at run - time. - - Resulting CFG after prologue peeling would be: - - bb_before_first_loop: - if ((scalar_loop_iterations <= th) - || - FIRST_NITERS == 0) GOTO bb_before_second_loop - GOTO first-loop - - first_loop: - do { - } while ... - - bb_before_second_loop: - - second_loop: - do { - } while ... - - orig_exit_bb: - */ - - bb_before_first_loop = split_edge (loop_preheader_edge (first_loop)); - bb_before_second_loop = split_edge (single_exit (first_loop)); - - /* Epilogue peeling. */ - if (!update_first_loop_count) - { - pre_condition = - fold_build2 (LE_EXPR, boolean_type_node, first_niters, - build_int_cst (TREE_TYPE (first_niters), 0)); - if (check_profitability) - { - tree scalar_loop_iters - = unshare_expr (LOOP_VINFO_NITERS_UNCHANGED - (loop_vec_info_for_loop (loop))); - cost_pre_condition = - fold_build2 (LE_EXPR, boolean_type_node, scalar_loop_iters, - build_int_cst (TREE_TYPE (scalar_loop_iters), th)); - - pre_condition = fold_build2 (TRUTH_OR_EXPR, boolean_type_node, - cost_pre_condition, pre_condition); - } - } - - /* Prologue peeling. */ - else - { - if (check_profitability) - set_prologue_iterations (bb_before_first_loop, first_niters, - loop, th); - - pre_condition = - fold_build2 (LE_EXPR, boolean_type_node, first_niters, - build_int_cst (TREE_TYPE (first_niters), 0)); - } - - skip_e = slpeel_add_loop_guard (bb_before_first_loop, pre_condition, - bb_before_second_loop, bb_before_first_loop); - slpeel_update_phi_nodes_for_guard1 (skip_e, first_loop, - first_loop == new_loop, - &new_exit_bb, &definitions); - - - /* 3. Add the guard that controls whether the second loop is executed. - Resulting CFG would be: - - bb_before_first_loop: - if (FIRST_NITERS == 0) GOTO bb_before_second_loop (skip first loop) - GOTO first-loop - - first_loop: - do { - } while ... - - bb_between_loops: - if (FIRST_NITERS == NITERS) GOTO bb_after_second_loop (skip second loop) - GOTO bb_before_second_loop - - bb_before_second_loop: - - second_loop: - do { - } while ... - - bb_after_second_loop: - - orig_exit_bb: - */ - - bb_between_loops = new_exit_bb; - bb_after_second_loop = split_edge (single_exit (second_loop)); - - pre_condition = - fold_build2 (EQ_EXPR, boolean_type_node, first_niters, niters); - skip_e = slpeel_add_loop_guard (bb_between_loops, pre_condition, - bb_after_second_loop, bb_before_first_loop); - slpeel_update_phi_nodes_for_guard2 (skip_e, second_loop, - second_loop == new_loop, &new_exit_bb); - - /* 4. Make first-loop iterate FIRST_NITERS times, if requested. - */ - if (update_first_loop_count) - slpeel_make_loop_iterate_ntimes (first_loop, first_niters); - - BITMAP_FREE (definitions); - delete_update_ssa (); - - return new_loop; -} - -/* Function vect_get_loop_location. - - Extract the location of the loop in the source code. - If the loop is not well formed for vectorization, an estimated - location is calculated. - Return the loop location if succeed and NULL if not. */ - -LOC -find_loop_location (struct loop *loop) -{ - gimple stmt = NULL; - basic_block bb; - gimple_stmt_iterator si; - - if (!loop) - return UNKNOWN_LOC; - - stmt = get_loop_exit_condition (loop); - - if (stmt && gimple_location (stmt) != UNKNOWN_LOC) - return gimple_location (stmt); - - /* If we got here the loop is probably not "well formed", - try to estimate the loop location */ - - if (!loop->header) - return UNKNOWN_LOC; - - bb = loop->header; - - for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si)) - { - stmt = gsi_stmt (si); - if (gimple_location (stmt) != UNKNOWN_LOC) - return gimple_location (stmt); - } - - return UNKNOWN_LOC; -} - - -/************************************************************************* - Vectorization Debug Information. - *************************************************************************/ /* Function vect_set_verbosity_level. @@ -1516,1262 +165,6 @@ vect_print_dump_info (enum verbosity_levels vl) } -/************************************************************************* - Vectorization Utilities. - *************************************************************************/ - -/* Function new_stmt_vec_info. - - Create and initialize a new stmt_vec_info struct for STMT. */ - -stmt_vec_info -new_stmt_vec_info (gimple stmt, loop_vec_info loop_vinfo) -{ - stmt_vec_info res; - res = (stmt_vec_info) xcalloc (1, sizeof (struct _stmt_vec_info)); - - STMT_VINFO_TYPE (res) = undef_vec_info_type; - STMT_VINFO_STMT (res) = stmt; - STMT_VINFO_LOOP_VINFO (res) = loop_vinfo; - STMT_VINFO_RELEVANT (res) = 0; - STMT_VINFO_LIVE_P (res) = false; - STMT_VINFO_VECTYPE (res) = NULL; - STMT_VINFO_VEC_STMT (res) = NULL; - STMT_VINFO_IN_PATTERN_P (res) = false; - STMT_VINFO_RELATED_STMT (res) = NULL; - STMT_VINFO_DATA_REF (res) = NULL; - - STMT_VINFO_DR_BASE_ADDRESS (res) = NULL; - STMT_VINFO_DR_OFFSET (res) = NULL; - STMT_VINFO_DR_INIT (res) = NULL; - STMT_VINFO_DR_STEP (res) = NULL; - STMT_VINFO_DR_ALIGNED_TO (res) = NULL; - - if (gimple_code (stmt) == GIMPLE_PHI - && is_loop_header_bb_p (gimple_bb (stmt))) - STMT_VINFO_DEF_TYPE (res) = vect_unknown_def_type; - else - STMT_VINFO_DEF_TYPE (res) = vect_loop_def; - STMT_VINFO_SAME_ALIGN_REFS (res) = VEC_alloc (dr_p, heap, 5); - STMT_VINFO_INSIDE_OF_LOOP_COST (res) = 0; - STMT_VINFO_OUTSIDE_OF_LOOP_COST (res) = 0; - STMT_SLP_TYPE (res) = 0; - DR_GROUP_FIRST_DR (res) = NULL; - DR_GROUP_NEXT_DR (res) = NULL; - DR_GROUP_SIZE (res) = 0; - DR_GROUP_STORE_COUNT (res) = 0; - DR_GROUP_GAP (res) = 0; - DR_GROUP_SAME_DR_STMT (res) = NULL; - DR_GROUP_READ_WRITE_DEPENDENCE (res) = false; - - return res; -} - -/* Create a hash table for stmt_vec_info. */ - -void -init_stmt_vec_info_vec (void) -{ - gcc_assert (!stmt_vec_info_vec); - stmt_vec_info_vec = VEC_alloc (vec_void_p, heap, 50); -} - -/* Free hash table for stmt_vec_info. */ - -void -free_stmt_vec_info_vec (void) -{ - gcc_assert (stmt_vec_info_vec); - VEC_free (vec_void_p, heap, stmt_vec_info_vec); -} - -/* Free stmt vectorization related info. */ - -void -free_stmt_vec_info (gimple stmt) -{ - stmt_vec_info stmt_info = vinfo_for_stmt (stmt); - - if (!stmt_info) - return; - - VEC_free (dr_p, heap, STMT_VINFO_SAME_ALIGN_REFS (stmt_info)); - set_vinfo_for_stmt (stmt, NULL); - free (stmt_info); -} - - -/* Function bb_in_loop_p - - Used as predicate for dfs order traversal of the loop bbs. */ - -static bool -bb_in_loop_p (const_basic_block bb, const void *data) -{ - const struct loop *const loop = (const struct loop *)data; - if (flow_bb_inside_loop_p (loop, bb)) - return true; - return false; -} - - -/* Function new_loop_vec_info. - - Create and initialize a new loop_vec_info struct for LOOP, as well as - stmt_vec_info structs for all the stmts in LOOP. */ - -loop_vec_info -new_loop_vec_info (struct loop *loop) -{ - loop_vec_info res; - basic_block *bbs; - gimple_stmt_iterator si; - unsigned int i, nbbs; - - res = (loop_vec_info) xcalloc (1, sizeof (struct _loop_vec_info)); - LOOP_VINFO_LOOP (res) = loop; - - bbs = get_loop_body (loop); - - /* Create/Update stmt_info for all stmts in the loop. */ - for (i = 0; i < loop->num_nodes; i++) - { - basic_block bb = bbs[i]; - - /* BBs in a nested inner-loop will have been already processed (because - we will have called vect_analyze_loop_form for any nested inner-loop). - Therefore, for stmts in an inner-loop we just want to update the - STMT_VINFO_LOOP_VINFO field of their stmt_info to point to the new - loop_info of the outer-loop we are currently considering to vectorize - (instead of the loop_info of the inner-loop). - For stmts in other BBs we need to create a stmt_info from scratch. */ - if (bb->loop_father != loop) - { - /* Inner-loop bb. */ - gcc_assert (loop->inner && bb->loop_father == loop->inner); - for (si = gsi_start_phis (bb); !gsi_end_p (si); gsi_next (&si)) - { - gimple phi = gsi_stmt (si); - stmt_vec_info stmt_info = vinfo_for_stmt (phi); - loop_vec_info inner_loop_vinfo = - STMT_VINFO_LOOP_VINFO (stmt_info); - gcc_assert (loop->inner == LOOP_VINFO_LOOP (inner_loop_vinfo)); - STMT_VINFO_LOOP_VINFO (stmt_info) = res; - } - for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si)) - { - gimple stmt = gsi_stmt (si); - stmt_vec_info stmt_info = vinfo_for_stmt (stmt); - loop_vec_info inner_loop_vinfo = - STMT_VINFO_LOOP_VINFO (stmt_info); - gcc_assert (loop->inner == LOOP_VINFO_LOOP (inner_loop_vinfo)); - STMT_VINFO_LOOP_VINFO (stmt_info) = res; - } - } - else - { - /* bb in current nest. */ - for (si = gsi_start_phis (bb); !gsi_end_p (si); gsi_next (&si)) - { - gimple phi = gsi_stmt (si); - gimple_set_uid (phi, 0); - set_vinfo_for_stmt (phi, new_stmt_vec_info (phi, res)); - } - - for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si)) - { - gimple stmt = gsi_stmt (si); - gimple_set_uid (stmt, 0); - set_vinfo_for_stmt (stmt, new_stmt_vec_info (stmt, res)); - } - } - } - - /* CHECKME: We want to visit all BBs before their successors (except for - latch blocks, for which this assertion wouldn't hold). In the simple - case of the loop forms we allow, a dfs order of the BBs would the same - as reversed postorder traversal, so we are safe. */ - - free (bbs); - bbs = XCNEWVEC (basic_block, loop->num_nodes); - nbbs = dfs_enumerate_from (loop->header, 0, bb_in_loop_p, - bbs, loop->num_nodes, loop); - gcc_assert (nbbs == loop->num_nodes); - - LOOP_VINFO_BBS (res) = bbs; - LOOP_VINFO_NITERS (res) = NULL; - LOOP_VINFO_NITERS_UNCHANGED (res) = NULL; - LOOP_VINFO_COST_MODEL_MIN_ITERS (res) = 0; - LOOP_VINFO_VECTORIZABLE_P (res) = 0; - LOOP_PEELING_FOR_ALIGNMENT (res) = 0; - LOOP_VINFO_VECT_FACTOR (res) = 0; - LOOP_VINFO_DATAREFS (res) = VEC_alloc (data_reference_p, heap, 10); - LOOP_VINFO_DDRS (res) = VEC_alloc (ddr_p, heap, 10 * 10); - LOOP_VINFO_UNALIGNED_DR (res) = NULL; - LOOP_VINFO_MAY_MISALIGN_STMTS (res) = - VEC_alloc (gimple, heap, - PARAM_VALUE (PARAM_VECT_MAX_VERSION_FOR_ALIGNMENT_CHECKS)); - LOOP_VINFO_MAY_ALIAS_DDRS (res) = - VEC_alloc (ddr_p, heap, - PARAM_VALUE (PARAM_VECT_MAX_VERSION_FOR_ALIAS_CHECKS)); - LOOP_VINFO_STRIDED_STORES (res) = VEC_alloc (gimple, heap, 10); - LOOP_VINFO_SLP_INSTANCES (res) = VEC_alloc (slp_instance, heap, 10); - LOOP_VINFO_SLP_UNROLLING_FACTOR (res) = 1; - - return res; -} - - -/* Function destroy_loop_vec_info. - - Free LOOP_VINFO struct, as well as all the stmt_vec_info structs of all the - stmts in the loop. */ - -void -destroy_loop_vec_info (loop_vec_info loop_vinfo, bool clean_stmts) -{ - struct loop *loop; - basic_block *bbs; - int nbbs; - gimple_stmt_iterator si; - int j; - VEC (slp_instance, heap) *slp_instances; - slp_instance instance; - - if (!loop_vinfo) - return; - - loop = LOOP_VINFO_LOOP (loop_vinfo); - - bbs = LOOP_VINFO_BBS (loop_vinfo); - nbbs = loop->num_nodes; - - if (!clean_stmts) - { - free (LOOP_VINFO_BBS (loop_vinfo)); - free_data_refs (LOOP_VINFO_DATAREFS (loop_vinfo)); - free_dependence_relations (LOOP_VINFO_DDRS (loop_vinfo)); - VEC_free (gimple, heap, LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo)); - - free (loop_vinfo); - loop->aux = NULL; - return; - } - - for (j = 0; j < nbbs; j++) - { - basic_block bb = bbs[j]; - - for (si = gsi_start_phis (bb); !gsi_end_p (si); gsi_next (&si)) - free_stmt_vec_info (gsi_stmt (si)); - - for (si = gsi_start_bb (bb); !gsi_end_p (si); ) - { - gimple stmt = gsi_stmt (si); - stmt_vec_info stmt_info = vinfo_for_stmt (stmt); - - if (stmt_info) - { - /* Check if this is a "pattern stmt" (introduced by the - vectorizer during the pattern recognition pass). */ - bool remove_stmt_p = false; - gimple orig_stmt = STMT_VINFO_RELATED_STMT (stmt_info); - if (orig_stmt) - { - stmt_vec_info orig_stmt_info = vinfo_for_stmt (orig_stmt); - if (orig_stmt_info - && STMT_VINFO_IN_PATTERN_P (orig_stmt_info)) - remove_stmt_p = true; - } - - /* Free stmt_vec_info. */ - free_stmt_vec_info (stmt); - - /* Remove dead "pattern stmts". */ - if (remove_stmt_p) - gsi_remove (&si, true); - } - gsi_next (&si); - } - } - - free (LOOP_VINFO_BBS (loop_vinfo)); - free_data_refs (LOOP_VINFO_DATAREFS (loop_vinfo)); - free_dependence_relations (LOOP_VINFO_DDRS (loop_vinfo)); - VEC_free (gimple, heap, LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo)); - VEC_free (ddr_p, heap, LOOP_VINFO_MAY_ALIAS_DDRS (loop_vinfo)); - slp_instances = LOOP_VINFO_SLP_INSTANCES (loop_vinfo); - for (j = 0; VEC_iterate (slp_instance, slp_instances, j, instance); j++) - vect_free_slp_instance (instance); - - VEC_free (slp_instance, heap, LOOP_VINFO_SLP_INSTANCES (loop_vinfo)); - VEC_free (gimple, heap, LOOP_VINFO_STRIDED_STORES (loop_vinfo)); - - free (loop_vinfo); - loop->aux = NULL; -} - - -/* Function vect_force_dr_alignment_p. - - Returns whether the alignment of a DECL can be forced to be aligned - on ALIGNMENT bit boundary. */ - -bool -vect_can_force_dr_alignment_p (const_tree decl, unsigned int alignment) -{ - if (TREE_CODE (decl) != VAR_DECL) - return false; - - if (DECL_EXTERNAL (decl)) - return false; - - if (TREE_ASM_WRITTEN (decl)) - return false; - - if (TREE_STATIC (decl)) - return (alignment <= MAX_OFILE_ALIGNMENT); - else - return (alignment <= MAX_STACK_ALIGNMENT); -} - - -/* Function get_vectype_for_scalar_type. - - Returns the vector type corresponding to SCALAR_TYPE as supported - by the target. */ - -tree -get_vectype_for_scalar_type (tree scalar_type) -{ - enum machine_mode inner_mode = TYPE_MODE (scalar_type); - int nbytes = GET_MODE_SIZE (inner_mode); - int nunits; - tree vectype; - - if (nbytes == 0 || nbytes >= UNITS_PER_SIMD_WORD (inner_mode)) - return NULL_TREE; - - /* FORNOW: Only a single vector size per mode (UNITS_PER_SIMD_WORD) - is expected. */ - nunits = UNITS_PER_SIMD_WORD (inner_mode) / nbytes; - - vectype = build_vector_type (scalar_type, nunits); - if (vect_print_dump_info (REPORT_DETAILS)) - { - fprintf (vect_dump, "get vectype with %d units of type ", nunits); - print_generic_expr (vect_dump, scalar_type, TDF_SLIM); - } - - if (!vectype) - return NULL_TREE; - - if (vect_print_dump_info (REPORT_DETAILS)) - { - fprintf (vect_dump, "vectype: "); - print_generic_expr (vect_dump, vectype, TDF_SLIM); - } - - if (!VECTOR_MODE_P (TYPE_MODE (vectype)) - && !INTEGRAL_MODE_P (TYPE_MODE (vectype))) - { - if (vect_print_dump_info (REPORT_DETAILS)) - fprintf (vect_dump, "mode not supported by target."); - return NULL_TREE; - } - - return vectype; -} - - -/* Function vect_supportable_dr_alignment - - Return whether the data reference DR is supported with respect to its - alignment. */ - -enum dr_alignment_support -vect_supportable_dr_alignment (struct data_reference *dr) -{ - gimple stmt = DR_STMT (dr); - stmt_vec_info stmt_info = vinfo_for_stmt (stmt); - tree vectype = STMT_VINFO_VECTYPE (stmt_info); - enum machine_mode mode = (int) TYPE_MODE (vectype); - struct loop *vect_loop = LOOP_VINFO_LOOP (STMT_VINFO_LOOP_VINFO (stmt_info)); - bool nested_in_vect_loop = nested_in_vect_loop_p (vect_loop, stmt); - bool invariant_in_outerloop = false; - - if (aligned_access_p (dr)) - return dr_aligned; - - if (nested_in_vect_loop) - { - tree outerloop_step = STMT_VINFO_DR_STEP (stmt_info); - invariant_in_outerloop = - (tree_int_cst_compare (outerloop_step, size_zero_node) == 0); - } - - /* Possibly unaligned access. */ - - /* We can choose between using the implicit realignment scheme (generating - a misaligned_move stmt) and the explicit realignment scheme (generating - aligned loads with a REALIGN_LOAD). There are two variants to the explicit - realignment scheme: optimized, and unoptimized. - We can optimize the realignment only if the step between consecutive - vector loads is equal to the vector size. Since the vector memory - accesses advance in steps of VS (Vector Size) in the vectorized loop, it - is guaranteed that the misalignment amount remains the same throughout the - execution of the vectorized loop. Therefore, we can create the - "realignment token" (the permutation mask that is passed to REALIGN_LOAD) - at the loop preheader. - - However, in the case of outer-loop vectorization, when vectorizing a - memory access in the inner-loop nested within the LOOP that is now being - vectorized, while it is guaranteed that the misalignment of the - vectorized memory access will remain the same in different outer-loop - iterations, it is *not* guaranteed that is will remain the same throughout - the execution of the inner-loop. This is because the inner-loop advances - with the original scalar step (and not in steps of VS). If the inner-loop - step happens to be a multiple of VS, then the misalignment remains fixed - and we can use the optimized realignment scheme. For example: - - for (i=0; i<N; i++) - for (j=0; j<M; j++) - s += a[i+j]; - - When vectorizing the i-loop in the above example, the step between - consecutive vector loads is 1, and so the misalignment does not remain - fixed across the execution of the inner-loop, and the realignment cannot - be optimized (as illustrated in the following pseudo vectorized loop): - - for (i=0; i<N; i+=4) - for (j=0; j<M; j++){ - vs += vp[i+j]; // misalignment of &vp[i+j] is {0,1,2,3,0,1,2,3,...} - // when j is {0,1,2,3,4,5,6,7,...} respectively. - // (assuming that we start from an aligned address). - } - - We therefore have to use the unoptimized realignment scheme: - - for (i=0; i<N; i+=4) - for (j=k; j<M; j+=4) - vs += vp[i+j]; // misalignment of &vp[i+j] is always k (assuming - // that the misalignment of the initial address is - // 0). - - The loop can then be vectorized as follows: - - for (k=0; k<4; k++){ - rt = get_realignment_token (&vp[k]); - for (i=0; i<N; i+=4){ - v1 = vp[i+k]; - for (j=k; j<M; j+=4){ - v2 = vp[i+j+VS-1]; - va = REALIGN_LOAD <v1,v2,rt>; - vs += va; - v1 = v2; - } - } - } */ - - if (DR_IS_READ (dr)) - { - if (optab_handler (vec_realign_load_optab, mode)->insn_code != - CODE_FOR_nothing - && (!targetm.vectorize.builtin_mask_for_load - || targetm.vectorize.builtin_mask_for_load ())) - { - tree vectype = STMT_VINFO_VECTYPE (stmt_info); - if (nested_in_vect_loop - && (TREE_INT_CST_LOW (DR_STEP (dr)) - != GET_MODE_SIZE (TYPE_MODE (vectype)))) - return dr_explicit_realign; - else - return dr_explicit_realign_optimized; - } - - if (optab_handler (movmisalign_optab, mode)->insn_code != - CODE_FOR_nothing) - /* Can't software pipeline the loads, but can at least do them. */ - return dr_unaligned_supported; - } - - /* Unsupported. */ - return dr_unaligned_unsupported; -} - - -/* Function vect_is_simple_use. - - Input: - LOOP - the loop that is being vectorized. - OPERAND - operand of a stmt in LOOP. - DEF - the defining stmt in case OPERAND is an SSA_NAME. - - Returns whether a stmt with OPERAND can be vectorized. - Supportable operands are constants, loop invariants, and operands that are - defined by the current iteration of the loop. Unsupportable operands are - those that are defined by a previous iteration of the loop (as is the case - in reduction/induction computations). */ - -bool -vect_is_simple_use (tree operand, loop_vec_info loop_vinfo, gimple *def_stmt, - tree *def, enum vect_def_type *dt) -{ - basic_block bb; - stmt_vec_info stmt_vinfo; - struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo); - - *def_stmt = NULL; - *def = NULL_TREE; - - if (vect_print_dump_info (REPORT_DETAILS)) - { - fprintf (vect_dump, "vect_is_simple_use: operand "); - print_generic_expr (vect_dump, operand, TDF_SLIM); - } - - if (TREE_CODE (operand) == INTEGER_CST || TREE_CODE (operand) == REAL_CST) - { - *dt = vect_constant_def; - return true; - } - if (is_gimple_min_invariant (operand)) - { - *def = operand; - *dt = vect_invariant_def; - return true; - } - - if (TREE_CODE (operand) == PAREN_EXPR) - { - if (vect_print_dump_info (REPORT_DETAILS)) - fprintf (vect_dump, "non-associatable copy."); - operand = TREE_OPERAND (operand, 0); - } - if (TREE_CODE (operand) != SSA_NAME) - { - if (vect_print_dump_info (REPORT_DETAILS)) - fprintf (vect_dump, "not ssa-name."); - return false; - } - - *def_stmt = SSA_NAME_DEF_STMT (operand); - if (*def_stmt == NULL) - { - if (vect_print_dump_info (REPORT_DETAILS)) - fprintf (vect_dump, "no def_stmt."); - return false; - } - - if (vect_print_dump_info (REPORT_DETAILS)) - { - fprintf (vect_dump, "def_stmt: "); - print_gimple_stmt (vect_dump, *def_stmt, 0, TDF_SLIM); - } - - /* empty stmt is expected only in case of a function argument. - (Otherwise - we expect a phi_node or a GIMPLE_ASSIGN). */ - if (gimple_nop_p (*def_stmt)) - { - *def = operand; - *dt = vect_invariant_def; - return true; - } - - bb = gimple_bb (*def_stmt); - if (!flow_bb_inside_loop_p (loop, bb)) - *dt = vect_invariant_def; - else - { - stmt_vinfo = vinfo_for_stmt (*def_stmt); - *dt = STMT_VINFO_DEF_TYPE (stmt_vinfo); - } - - if (*dt == vect_unknown_def_type) - { - if (vect_print_dump_info (REPORT_DETAILS)) - fprintf (vect_dump, "Unsupported pattern."); - return false; - } - - if (vect_print_dump_info (REPORT_DETAILS)) - fprintf (vect_dump, "type of def: %d.",*dt); - - switch (gimple_code (*def_stmt)) - { - case GIMPLE_PHI: - *def = gimple_phi_result (*def_stmt); - break; - - case GIMPLE_ASSIGN: - *def = gimple_assign_lhs (*def_stmt); - break; - - case GIMPLE_CALL: - *def = gimple_call_lhs (*def_stmt); - if (*def != NULL) - break; - /* FALLTHRU */ - default: - if (vect_print_dump_info (REPORT_DETAILS)) - fprintf (vect_dump, "unsupported defining stmt: "); - return false; - } - - return true; -} - - -/* Function supportable_widening_operation - - Check whether an operation represented by the code CODE is a - widening operation that is supported by the target platform in - vector form (i.e., when operating on arguments of type VECTYPE). - - Widening operations we currently support are NOP (CONVERT), FLOAT - and WIDEN_MULT. This function checks if these operations are supported - by the target platform either directly (via vector tree-codes), or via - target builtins. - - Output: - - CODE1 and CODE2 are codes of vector operations to be used when - vectorizing the operation, if available. - - DECL1 and DECL2 are decls of target builtin functions to be used - when vectorizing the operation, if available. In this case, - CODE1 and CODE2 are CALL_EXPR. - - MULTI_STEP_CVT determines the number of required intermediate steps in - case of multi-step conversion (like char->short->int - in that case - MULTI_STEP_CVT will be 1). - - INTERM_TYPES contains the intermediate type required to perform the - widening operation (short in the above example). */ - -bool -supportable_widening_operation (enum tree_code code, gimple stmt, tree vectype, - tree *decl1, tree *decl2, - enum tree_code *code1, enum tree_code *code2, - int *multi_step_cvt, - VEC (tree, heap) **interm_types) -{ - stmt_vec_info stmt_info = vinfo_for_stmt (stmt); - loop_vec_info loop_info = STMT_VINFO_LOOP_VINFO (stmt_info); - struct loop *vect_loop = LOOP_VINFO_LOOP (loop_info); - bool ordered_p; - enum machine_mode vec_mode; - enum insn_code icode1 = 0, icode2 = 0; - optab optab1, optab2; - tree type = gimple_expr_type (stmt); - tree wide_vectype = get_vectype_for_scalar_type (type); - enum tree_code c1, c2; - - /* The result of a vectorized widening operation usually requires two vectors - (because the widened results do not fit int one vector). The generated - vector results would normally be expected to be generated in the same - order as in the original scalar computation, i.e. if 8 results are - generated in each vector iteration, they are to be organized as follows: - vect1: [res1,res2,res3,res4], vect2: [res5,res6,res7,res8]. - - However, in the special case that the result of the widening operation is - used in a reduction computation only, the order doesn't matter (because - when vectorizing a reduction we change the order of the computation). - Some targets can take advantage of this and generate more efficient code. - For example, targets like Altivec, that support widen_mult using a sequence - of {mult_even,mult_odd} generate the following vectors: - vect1: [res1,res3,res5,res7], vect2: [res2,res4,res6,res8]. - - When vectorizing outer-loops, we execute the inner-loop sequentially - (each vectorized inner-loop iteration contributes to VF outer-loop - iterations in parallel). We therefore don't allow to change the order - of the computation in the inner-loop during outer-loop vectorization. */ - - if (STMT_VINFO_RELEVANT (stmt_info) == vect_used_by_reduction - && !nested_in_vect_loop_p (vect_loop, stmt)) - ordered_p = false; - else - ordered_p = true; - - if (!ordered_p - && code == WIDEN_MULT_EXPR - && targetm.vectorize.builtin_mul_widen_even - && targetm.vectorize.builtin_mul_widen_even (vectype) - && targetm.vectorize.builtin_mul_widen_odd - && targetm.vectorize.builtin_mul_widen_odd (vectype)) - { - if (vect_print_dump_info (REPORT_DETAILS)) - fprintf (vect_dump, "Unordered widening operation detected."); - - *code1 = *code2 = CALL_EXPR; - *decl1 = targetm.vectorize.builtin_mul_widen_even (vectype); - *decl2 = targetm.vectorize.builtin_mul_widen_odd (vectype); - return true; - } - - switch (code) - { - case WIDEN_MULT_EXPR: - if (BYTES_BIG_ENDIAN) - { - c1 = VEC_WIDEN_MULT_HI_EXPR; - c2 = VEC_WIDEN_MULT_LO_EXPR; - } - else - { - c2 = VEC_WIDEN_MULT_HI_EXPR; - c1 = VEC_WIDEN_MULT_LO_EXPR; - } - break; - - CASE_CONVERT: - if (BYTES_BIG_ENDIAN) - { - c1 = VEC_UNPACK_HI_EXPR; - c2 = VEC_UNPACK_LO_EXPR; - } - else - { - c2 = VEC_UNPACK_HI_EXPR; - c1 = VEC_UNPACK_LO_EXPR; - } - break; - - case FLOAT_EXPR: - if (BYTES_BIG_ENDIAN) - { - c1 = VEC_UNPACK_FLOAT_HI_EXPR; - c2 = VEC_UNPACK_FLOAT_LO_EXPR; - } - else - { - c2 = VEC_UNPACK_FLOAT_HI_EXPR; - c1 = VEC_UNPACK_FLOAT_LO_EXPR; - } - break; - - case FIX_TRUNC_EXPR: - /* ??? Not yet implemented due to missing VEC_UNPACK_FIX_TRUNC_HI_EXPR/ - VEC_UNPACK_FIX_TRUNC_LO_EXPR tree codes and optabs used for - computing the operation. */ - return false; - - default: - gcc_unreachable (); - } - - if (code == FIX_TRUNC_EXPR) - { - /* The signedness is determined from output operand. */ - optab1 = optab_for_tree_code (c1, type, optab_default); - optab2 = optab_for_tree_code (c2, type, optab_default); - } - else - { - optab1 = optab_for_tree_code (c1, vectype, optab_default); - optab2 = optab_for_tree_code (c2, vectype, optab_default); - } - - if (!optab1 || !optab2) - return false; - - vec_mode = TYPE_MODE (vectype); - if ((icode1 = optab_handler (optab1, vec_mode)->insn_code) == CODE_FOR_nothing - || (icode2 = optab_handler (optab2, vec_mode)->insn_code) - == CODE_FOR_nothing) - return false; - - /* Check if it's a multi-step conversion that can be done using intermediate - types. */ - if (insn_data[icode1].operand[0].mode != TYPE_MODE (wide_vectype) - || insn_data[icode2].operand[0].mode != TYPE_MODE (wide_vectype)) - { - int i; - tree prev_type = vectype, intermediate_type; - enum machine_mode intermediate_mode, prev_mode = vec_mode; - optab optab3, optab4; - - if (!CONVERT_EXPR_CODE_P (code)) - return false; - - *code1 = c1; - *code2 = c2; - - /* We assume here that there will not be more than MAX_INTERM_CVT_STEPS - intermediate steps in promotion sequence. We try MAX_INTERM_CVT_STEPS - to get to NARROW_VECTYPE, and fail if we do not. */ - *interm_types = VEC_alloc (tree, heap, MAX_INTERM_CVT_STEPS); - for (i = 0; i < 3; i++) - { - intermediate_mode = insn_data[icode1].operand[0].mode; - intermediate_type = lang_hooks.types.type_for_mode (intermediate_mode, - TYPE_UNSIGNED (prev_type)); - optab3 = optab_for_tree_code (c1, intermediate_type, optab_default); - optab4 = optab_for_tree_code (c2, intermediate_type, optab_default); - - if (!optab3 || !optab4 - || (icode1 = optab1->handlers[(int) prev_mode].insn_code) - == CODE_FOR_nothing - || insn_data[icode1].operand[0].mode != intermediate_mode - || (icode2 = optab2->handlers[(int) prev_mode].insn_code) - == CODE_FOR_nothing - || insn_data[icode2].operand[0].mode != intermediate_mode - || (icode1 = optab3->handlers[(int) intermediate_mode].insn_code) - == CODE_FOR_nothing - || (icode2 = optab4->handlers[(int) intermediate_mode].insn_code) - == CODE_FOR_nothing) - return false; - - VEC_quick_push (tree, *interm_types, intermediate_type); - (*multi_step_cvt)++; - - if (insn_data[icode1].operand[0].mode == TYPE_MODE (wide_vectype) - && insn_data[icode2].operand[0].mode == TYPE_MODE (wide_vectype)) - return true; - - prev_type = intermediate_type; - prev_mode = intermediate_mode; - } - - return false; - } - - *code1 = c1; - *code2 = c2; - return true; -} - - -/* Function supportable_narrowing_operation - - Check whether an operation represented by the code CODE is a - narrowing operation that is supported by the target platform in - vector form (i.e., when operating on arguments of type VECTYPE). - - Narrowing operations we currently support are NOP (CONVERT) and - FIX_TRUNC. This function checks if these operations are supported by - the target platform directly via vector tree-codes. - - Output: - - CODE1 is the code of a vector operation to be used when - vectorizing the operation, if available. - - MULTI_STEP_CVT determines the number of required intermediate steps in - case of multi-step conversion (like int->short->char - in that case - MULTI_STEP_CVT will be 1). - - INTERM_TYPES contains the intermediate type required to perform the - narrowing operation (short in the above example). */ - -bool -supportable_narrowing_operation (enum tree_code code, - const_gimple stmt, tree vectype, - enum tree_code *code1, int *multi_step_cvt, - VEC (tree, heap) **interm_types) -{ - enum machine_mode vec_mode; - enum insn_code icode1; - optab optab1, interm_optab; - tree type = gimple_expr_type (stmt); - tree narrow_vectype = get_vectype_for_scalar_type (type); - enum tree_code c1; - tree intermediate_type, prev_type; - int i; - - switch (code) - { - CASE_CONVERT: - c1 = VEC_PACK_TRUNC_EXPR; - break; - - case FIX_TRUNC_EXPR: - c1 = VEC_PACK_FIX_TRUNC_EXPR; - break; - - case FLOAT_EXPR: - /* ??? Not yet implemented due to missing VEC_PACK_FLOAT_EXPR - tree code and optabs used for computing the operation. */ - return false; - - default: - gcc_unreachable (); - } - - if (code == FIX_TRUNC_EXPR) - /* The signedness is determined from output operand. */ - optab1 = optab_for_tree_code (c1, type, optab_default); - else - optab1 = optab_for_tree_code (c1, vectype, optab_default); - - if (!optab1) - return false; - - vec_mode = TYPE_MODE (vectype); - if ((icode1 = optab_handler (optab1, vec_mode)->insn_code) - == CODE_FOR_nothing) - return false; - - /* Check if it's a multi-step conversion that can be done using intermediate - types. */ - if (insn_data[icode1].operand[0].mode != TYPE_MODE (narrow_vectype)) - { - enum machine_mode intermediate_mode, prev_mode = vec_mode; - - *code1 = c1; - prev_type = vectype; - /* We assume here that there will not be more than MAX_INTERM_CVT_STEPS - intermediate steps in promotion sequence. We try MAX_INTERM_CVT_STEPS - to get to NARROW_VECTYPE, and fail if we do not. */ - *interm_types = VEC_alloc (tree, heap, MAX_INTERM_CVT_STEPS); - for (i = 0; i < 3; i++) - { - intermediate_mode = insn_data[icode1].operand[0].mode; - intermediate_type = lang_hooks.types.type_for_mode (intermediate_mode, - TYPE_UNSIGNED (prev_type)); - interm_optab = optab_for_tree_code (c1, intermediate_type, - optab_default); - if (!interm_optab - || (icode1 = optab1->handlers[(int) prev_mode].insn_code) - == CODE_FOR_nothing - || insn_data[icode1].operand[0].mode != intermediate_mode - || (icode1 - = interm_optab->handlers[(int) intermediate_mode].insn_code) - == CODE_FOR_nothing) - return false; - - VEC_quick_push (tree, *interm_types, intermediate_type); - (*multi_step_cvt)++; - - if (insn_data[icode1].operand[0].mode == TYPE_MODE (narrow_vectype)) - return true; - - prev_type = intermediate_type; - prev_mode = intermediate_mode; - } - - return false; - } - - *code1 = c1; - return true; -} - - -/* Function reduction_code_for_scalar_code - - Input: - CODE - tree_code of a reduction operations. - - Output: - REDUC_CODE - the corresponding tree-code to be used to reduce the - vector of partial results into a single scalar result (which - will also reside in a vector). - - Return TRUE if a corresponding REDUC_CODE was found, FALSE otherwise. */ - -bool -reduction_code_for_scalar_code (enum tree_code code, - enum tree_code *reduc_code) -{ - switch (code) - { - case MAX_EXPR: - *reduc_code = REDUC_MAX_EXPR; - return true; - - case MIN_EXPR: - *reduc_code = REDUC_MIN_EXPR; - return true; - - case PLUS_EXPR: - *reduc_code = REDUC_PLUS_EXPR; - return true; - - default: - return false; - } -} - -/* Error reporting helper for vect_is_simple_reduction below. GIMPLE statement - STMT is printed with a message MSG. */ - -static void -report_vect_op (gimple stmt, const char *msg) -{ - fprintf (vect_dump, "%s", msg); - print_gimple_stmt (vect_dump, stmt, 0, TDF_SLIM); -} - -/* Function vect_is_simple_reduction - - Detect a cross-iteration def-use cycle that represents a simple - reduction computation. We look for the following pattern: - - loop_header: - a1 = phi < a0, a2 > - a3 = ... - a2 = operation (a3, a1) - - such that: - 1. operation is commutative and associative and it is safe to - change the order of the computation. - 2. no uses for a2 in the loop (a2 is used out of the loop) - 3. no uses of a1 in the loop besides the reduction operation. - - Condition 1 is tested here. - Conditions 2,3 are tested in vect_mark_stmts_to_be_vectorized. */ - -gimple -vect_is_simple_reduction (loop_vec_info loop_info, gimple phi) -{ - struct loop *loop = (gimple_bb (phi))->loop_father; - struct loop *vect_loop = LOOP_VINFO_LOOP (loop_info); - edge latch_e = loop_latch_edge (loop); - tree loop_arg = PHI_ARG_DEF_FROM_EDGE (phi, latch_e); - gimple def_stmt, def1, def2; - enum tree_code code; - tree op1, op2; - tree type; - int nloop_uses; - tree name; - imm_use_iterator imm_iter; - use_operand_p use_p; - - gcc_assert (loop == vect_loop || flow_loop_nested_p (vect_loop, loop)); - - name = PHI_RESULT (phi); - nloop_uses = 0; - FOR_EACH_IMM_USE_FAST (use_p, imm_iter, name) - { - gimple use_stmt = USE_STMT (use_p); - if (flow_bb_inside_loop_p (loop, gimple_bb (use_stmt)) - && vinfo_for_stmt (use_stmt) - && !is_pattern_stmt_p (vinfo_for_stmt (use_stmt))) - nloop_uses++; - if (nloop_uses > 1) - { - if (vect_print_dump_info (REPORT_DETAILS)) - fprintf (vect_dump, "reduction used in loop."); - return NULL; - } - } - - if (TREE_CODE (loop_arg) != SSA_NAME) - { - if (vect_print_dump_info (REPORT_DETAILS)) - { - fprintf (vect_dump, "reduction: not ssa_name: "); - print_generic_expr (vect_dump, loop_arg, TDF_SLIM); - } - return NULL; - } - - def_stmt = SSA_NAME_DEF_STMT (loop_arg); - if (!def_stmt) - { - if (vect_print_dump_info (REPORT_DETAILS)) - fprintf (vect_dump, "reduction: no def_stmt."); - return NULL; - } - - if (!is_gimple_assign (def_stmt)) - { - if (vect_print_dump_info (REPORT_DETAILS)) - print_gimple_stmt (vect_dump, def_stmt, 0, TDF_SLIM); - return NULL; - } - - name = gimple_assign_lhs (def_stmt); - nloop_uses = 0; - FOR_EACH_IMM_USE_FAST (use_p, imm_iter, name) - { - gimple use_stmt = USE_STMT (use_p); - if (flow_bb_inside_loop_p (loop, gimple_bb (use_stmt)) - && vinfo_for_stmt (use_stmt) - && !is_pattern_stmt_p (vinfo_for_stmt (use_stmt))) - nloop_uses++; - if (nloop_uses > 1) - { - if (vect_print_dump_info (REPORT_DETAILS)) - fprintf (vect_dump, "reduction used in loop."); - return NULL; - } - } - - code = gimple_assign_rhs_code (def_stmt); - - if (!commutative_tree_code (code) || !associative_tree_code (code)) - { - if (vect_print_dump_info (REPORT_DETAILS)) - report_vect_op (def_stmt, "reduction: not commutative/associative: "); - return NULL; - } - - if (get_gimple_rhs_class (code) != GIMPLE_BINARY_RHS) - { - if (vect_print_dump_info (REPORT_DETAILS)) - report_vect_op (def_stmt, "reduction: not binary operation: "); - return NULL; - } - - op1 = gimple_assign_rhs1 (def_stmt); - op2 = gimple_assign_rhs2 (def_stmt); - if (TREE_CODE (op1) != SSA_NAME || TREE_CODE (op2) != SSA_NAME) - { - if (vect_print_dump_info (REPORT_DETAILS)) - report_vect_op (def_stmt, "reduction: uses not ssa_names: "); - return NULL; - } - - /* Check that it's ok to change the order of the computation. */ - type = TREE_TYPE (gimple_assign_lhs (def_stmt)); - if (TYPE_MAIN_VARIANT (type) != TYPE_MAIN_VARIANT (TREE_TYPE (op1)) - || TYPE_MAIN_VARIANT (type) != TYPE_MAIN_VARIANT (TREE_TYPE (op2))) - { - if (vect_print_dump_info (REPORT_DETAILS)) - { - fprintf (vect_dump, "reduction: multiple types: operation type: "); - print_generic_expr (vect_dump, type, TDF_SLIM); - fprintf (vect_dump, ", operands types: "); - print_generic_expr (vect_dump, TREE_TYPE (op1), TDF_SLIM); - fprintf (vect_dump, ","); - print_generic_expr (vect_dump, TREE_TYPE (op2), TDF_SLIM); - } - return NULL; - } - - /* Generally, when vectorizing a reduction we change the order of the - computation. This may change the behavior of the program in some - cases, so we need to check that this is ok. One exception is when - vectorizing an outer-loop: the inner-loop is executed sequentially, - and therefore vectorizing reductions in the inner-loop during - outer-loop vectorization is safe. */ - - /* CHECKME: check for !flag_finite_math_only too? */ - if (SCALAR_FLOAT_TYPE_P (type) && !flag_associative_math - && !nested_in_vect_loop_p (vect_loop, def_stmt)) - { - /* Changing the order of operations changes the semantics. */ - if (vect_print_dump_info (REPORT_DETAILS)) - report_vect_op (def_stmt, "reduction: unsafe fp math optimization: "); - return NULL; - } - else if (INTEGRAL_TYPE_P (type) && TYPE_OVERFLOW_TRAPS (type) - && !nested_in_vect_loop_p (vect_loop, def_stmt)) - { - /* Changing the order of operations changes the semantics. */ - if (vect_print_dump_info (REPORT_DETAILS)) - report_vect_op (def_stmt, "reduction: unsafe int math optimization: "); - return NULL; - } - else if (SAT_FIXED_POINT_TYPE_P (type)) - { - /* Changing the order of operations changes the semantics. */ - if (vect_print_dump_info (REPORT_DETAILS)) - report_vect_op (def_stmt, - "reduction: unsafe fixed-point math optimization: "); - return NULL; - } - - /* reduction is safe. we're dealing with one of the following: - 1) integer arithmetic and no trapv - 2) floating point arithmetic, and special flags permit this optimization. - */ - def1 = SSA_NAME_DEF_STMT (op1); - def2 = SSA_NAME_DEF_STMT (op2); - if (!def1 || !def2 || gimple_nop_p (def1) || gimple_nop_p (def2)) - { - if (vect_print_dump_info (REPORT_DETAILS)) - report_vect_op (def_stmt, "reduction: no defs for operands: "); - return NULL; - } - - - /* Check that one def is the reduction def, defined by PHI, - the other def is either defined in the loop ("vect_loop_def"), - or it's an induction (defined by a loop-header phi-node). */ - - if (def2 == phi - && flow_bb_inside_loop_p (loop, gimple_bb (def1)) - && (is_gimple_assign (def1) - || STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def1)) == vect_induction_def - || (gimple_code (def1) == GIMPLE_PHI - && STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def1)) == vect_loop_def - && !is_loop_header_bb_p (gimple_bb (def1))))) - { - if (vect_print_dump_info (REPORT_DETAILS)) - report_vect_op (def_stmt, "detected reduction:"); - return def_stmt; - } - else if (def1 == phi - && flow_bb_inside_loop_p (loop, gimple_bb (def2)) - && (is_gimple_assign (def2) - || STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def2)) == vect_induction_def - || (gimple_code (def2) == GIMPLE_PHI - && STMT_VINFO_DEF_TYPE (vinfo_for_stmt (def2)) == vect_loop_def - && !is_loop_header_bb_p (gimple_bb (def2))))) - { - /* Swap operands (just for simplicity - so that the rest of the code - can assume that the reduction variable is always the last (second) - argument). */ - if (vect_print_dump_info (REPORT_DETAILS)) - report_vect_op (def_stmt , - "detected reduction: need to swap operands:"); - swap_tree_operands (def_stmt, gimple_assign_rhs1_ptr (def_stmt), - gimple_assign_rhs2_ptr (def_stmt)); - return def_stmt; - } - else - { - if (vect_print_dump_info (REPORT_DETAILS)) - report_vect_op (def_stmt, "reduction: unknown pattern."); - return NULL; - } -} - - -/* Function vect_is_simple_iv_evolution. - - FORNOW: A simple evolution of an induction variables in the loop is - considered a polynomial evolution with constant step. */ - -bool -vect_is_simple_iv_evolution (unsigned loop_nb, tree access_fn, tree * init, - tree * step) -{ - tree init_expr; - tree step_expr; - tree evolution_part = evolution_part_in_loop_num (access_fn, loop_nb); - - /* When there is no evolution in this loop, the evolution function - is not "simple". */ - if (evolution_part == NULL_TREE) - return false; - - /* When the evolution is a polynomial of degree >= 2 - the evolution function is not "simple". */ - if (tree_is_chrec (evolution_part)) - return false; - - step_expr = evolution_part; - init_expr = unshare_expr (initial_condition_in_loop_num (access_fn, loop_nb)); - - if (vect_print_dump_info (REPORT_DETAILS)) - { - fprintf (vect_dump, "step: "); - print_generic_expr (vect_dump, step_expr, TDF_SLIM); - fprintf (vect_dump, ", init: "); - print_generic_expr (vect_dump, init_expr, TDF_SLIM); - } - - *init = init_expr; - *step = step_expr; - - if (TREE_CODE (step_expr) != INTEGER_CST) - { - if (vect_print_dump_info (REPORT_DETAILS)) - fprintf (vect_dump, "step unknown."); - return false; - } - - return true; -} - - /* Function vectorize_loops. Entry Point to loop vectorization phase. */ @@ -2849,6 +242,7 @@ vectorize_loops (void) return num_vectorized_loops > 0 ? TODO_cleanup_cfg : 0; } + /* Increase alignment of global arrays to improve vectorization potential. TODO: @@ -2871,49 +265,53 @@ increase_alignment (void) unsigned int alignment; if (TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE) - continue; + continue; vectype = get_vectype_for_scalar_type (TREE_TYPE (TREE_TYPE (decl))); if (!vectype) - continue; + continue; alignment = TYPE_ALIGN (vectype); if (DECL_ALIGN (decl) >= alignment) - continue; + continue; if (vect_can_force_dr_alignment_p (decl, alignment)) - { - DECL_ALIGN (decl) = TYPE_ALIGN (vectype); - DECL_USER_ALIGN (decl) = 1; - if (dump_file) - { - fprintf (dump_file, "Increasing alignment of decl: "); - print_generic_expr (dump_file, decl, TDF_SLIM); - } - } + { + DECL_ALIGN (decl) = TYPE_ALIGN (vectype); + DECL_USER_ALIGN (decl) = 1; + if (dump_file) + { + fprintf (dump_file, "Increasing alignment of decl: "); + print_generic_expr (dump_file, decl, TDF_SLIM); + } + } } return 0; } + static bool gate_increase_alignment (void) { return flag_section_anchors && flag_tree_vectorize; } -struct simple_ipa_opt_pass pass_ipa_increase_alignment = + +struct simple_ipa_opt_pass pass_ipa_increase_alignment = { { SIMPLE_IPA_PASS, - "increase_alignment", /* name */ - gate_increase_alignment, /* gate */ - increase_alignment, /* execute */ - NULL, /* sub */ - NULL, /* next */ - 0, /* static_pass_number */ - 0, /* tv_id */ - 0, /* properties_required */ - 0, /* properties_provided */ - 0, /* properties_destroyed */ - 0, /* todo_flags_start */ - 0 /* todo_flags_finish */ + "increase_alignment", /* name */ + gate_increase_alignment, /* gate */ + increase_alignment, /* execute */ + NULL, /* sub */ + NULL, /* next */ + 0, /* static_pass_number */ + 0, /* tv_id */ + 0, /* properties_required */ + 0, /* properties_provided */ + 0, /* properties_destroyed */ + 0, /* todo_flags_start */ + 0 /* todo_flags_finish */ } }; + + |