CbC/CbC_gcc: gcc/tree-vectorizer.c comparison

comparison gcc/tree-vectorizer.c @ 55:77e2b8dfacca gcc-4.4.5

update it from 4.4.3 to 4.5.0

author	ryoma <e075725@ie.u-ryukyu.ac.jp>
date	Fri, 12 Feb 2010 23:39:51 +0900
parents	a06113de4d67
children	b7f97abdc517

comparison

equal deleted inserted replaced

-:c156f1bd5cd9
+:77e2b8dfacca
-/* Loop Vectorization
+/* Vectorizer
-Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Free Software
+Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software
 Foundation, Inc.
 Contributed by Dorit Naishlos <dorit@il.ibm.com>
 This file is part of GCC.
 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.
+/* Loop and basic block vectorizer.
-This pass tries to vectorize loops. This first implementation focuses on
+This file contains drivers for the three vectorizers:
-simple inner-most loops, with no conditional control flow, and a set of
+(1) loop vectorizer (inter-iteration parallelism),
-simple operations which vector form can be expressed using existing
+(2) loop-aware SLP (intra-iteration parallelism) (invoked by the loop
-tree codes (PLUS, MULT etc).
+vectorizer)
+(3) BB vectorizer (out-of-loops), aka SLP
-For example, the vectorizer transforms the following simple loop:
+The rest of the vectorizer's code is organized as follows:
-	short a[N]; short b[N]; short c[N]; int i;
+- tree-vect-loop.c - loop specific parts such as reductions, etc. These are
+used by drivers (1) and (2).
-	for (i=0; i<N; i++){
+- tree-vect-loop-manip.c - vectorizer's loop control-flow utilities, used by
-	  a[i] = b[i] + c[i];
+drivers (1) and (2).
-	}
+- tree-vect-slp.c - BB vectorization specific analysis and transformation,
+used by drivers (2) and (3).
-as if it was manually vectorized by rewriting the source code into:
+- tree-vect-stmts.c - statements analysis and transformation (used by all).
+- tree-vect-data-refs.c - vectorizer specific data-refs analysis and
-	typedef int __attribute__((mode(V8HI))) v8hi;
+manipulations (used by all).
-	short a[N];  short b[N]; short c[N];   int i;
+- tree-vect-patterns.c - vectorizable code patterns detector (used by all)
-	v8hi *pa = (v8hi*)a, *pb = (v8hi*)b, *pc = (v8hi*)c;
-	v8hi va, vb, vc;
+Here's a poor attempt at illustrating that:
-	for (i=0; i<N/8; i++){
+tree-vectorizer.c:
-	  vb = pb[i];
+loop_vect()  loop_aware_slp()  slp_vect()
-	  vc = pc[i];
+|        /           \          /
-	  va = vb + vc;
+|       /             \        /
-	  pa[i] = va;
+tree-vect-loop.c  tree-vect-slp.c
-	}
+| \      \  /      /   |
+|  \      \/      /    |
-	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
+tree-vect-stmts.c  tree-vect-data-refs.c
-had successfully passed the analysis phase.
+\      /
+tree-vect-patterns.c
-	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
 */
 #include "config.h"
 #include "system.h"
 #include "coretypes.h"
 #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"
+#include "timevar.h"
-/*************************************************************************
-General Vectorization Utilities
-*************************************************************************/
 /* vect_dump will be set to stderr or dump_file if exist.  */
 FILE *vect_dump;
 /* vect_verbosity_level set to an invalid value
 to mark that it's uninitialized.  */
-enum verbosity_levels vect_verbosity_level = MAX_VERBOSITY_LEVEL;
+static enum verbosity_levels vect_verbosity_level = MAX_VERBOSITY_LEVEL;
+static enum verbosity_levels user_vect_verbosity_level = MAX_VERBOSITY_LEVEL;
-/* Loop location.  */
-static LOC vect_loop_location;
+/* Loop or bb location.  */
+LOC vect_location;
-/* Bitmap of virtual variables to be renamed.  */
-bitmap vect_memsyms_to_rename;
 /* Vector mapping GIMPLE stmt to stmt_vec_info. */
 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.
-Called from toplev.c upon detection of the
+Called from opts.c upon detection of the
 -ftree-vectorizer-verbose=N option.  */
 void
 vect_set_verbosity_level (const char *val)
 {
 unsigned int vl;
 vl = atoi (val);
 if (vl < MAX_VERBOSITY_LEVEL)
-vect_verbosity_level = vl;
+user_vect_verbosity_level = (enum verbosity_levels) vl;
 else
-vect_verbosity_level = MAX_VERBOSITY_LEVEL - 1;
+user_vect_verbosity_level
+= (enum verbosity_levels) (MAX_VERBOSITY_LEVEL - 1);
 }
 /* Function vect_set_dump_settings.
 Decide where to print the debugging information (dump_file/stderr).
 If the user defined the verbosity level, but there is no dump file,
 print to stderr, otherwise print to the dump file.  */
 static void
-vect_set_dump_settings (void)
+vect_set_dump_settings (bool slp)
 {
 vect_dump = dump_file;
 /* Check if the verbosity level was defined by the user:  */
-if (vect_verbosity_level != MAX_VERBOSITY_LEVEL)
+if (user_vect_verbosity_level != MAX_VERBOSITY_LEVEL)
 {
-/* If there is no dump file, print to stderr.  */
+vect_verbosity_level = user_vect_verbosity_level;
-if (!dump_file)
+/* Ignore user defined verbosity if dump flags require higher level of
-vect_dump = stderr;
+verbosity.  */
-return;
+if (dump_file)
+{
+if (((dump_flags & TDF_DETAILS)
+&& vect_verbosity_level >= REPORT_DETAILS)
+	       || ((dump_flags & TDF_STATS)
+	            && vect_verbosity_level >= REPORT_UNVECTORIZED_LOCATIONS))
+return;
+}
+else
+{
+/* If there is no dump file, print to stderr in case of loop
+vectorization.  */
+if (!slp)
+vect_dump = stderr;
+return;
+}
 }
 /* User didn't specify verbosity level:  */
 if (dump_file && (dump_flags & TDF_DETAILS))
 vect_verbosity_level = REPORT_DETAILS;
 else if (dump_file && (dump_flags & TDF_STATS))
-vect_verbosity_level = REPORT_UNVECTORIZED_LOOPS;
+vect_verbosity_level = REPORT_UNVECTORIZED_LOCATIONS;
 else
 vect_verbosity_level = REPORT_NONE;
 gcc_assert (dump_file || vect_verbosity_level == REPORT_NONE);
 }
 return false;
 if (!current_function_decl || !vect_dump)
 return false;
-if (vect_loop_location == UNKNOWN_LOC)
+if (vect_location == UNKNOWN_LOC)
 fprintf (vect_dump, "\n%s:%d: note: ",
 	     DECL_SOURCE_FILE (current_function_decl),
 	     DECL_SOURCE_LINE (current_function_decl));
 else
 fprintf (vect_dump, "\n%s:%d: note: ",
-	     LOC_FILE (vect_loop_location), LOC_LINE (vect_loop_location));
+	     LOC_FILE (vect_location), LOC_LINE (vect_location));
 return true;
 }
-/*************************************************************************
-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.  */
+Entry point to loop vectorization phase.  */
 unsigned
 vectorize_loops (void)
 {
 unsigned int i;
 /* Bail out if there are no loops.  */
 if (vect_loops_num <= 1)
 return 0;
 /* Fix the verbosity level if not defined explicitly by the user.  */
-vect_set_dump_settings ();
+vect_set_dump_settings (false);
-/* Allocate the bitmap that records which virtual variables that
-need to be renamed.  */
-vect_memsyms_to_rename = BITMAP_ALLOC (NULL);
 init_stmt_vec_info_vec ();
 /*  ----------- Analyze loops. -----------  */
 /* If some loop was duplicated, it gets bigger number
 than all previously defined loops. This fact allows us to run
 only over initial loops skipping newly generated ones.  */
 FOR_EACH_LOOP (li, loop, 0)
 if (optimize_loop_nest_for_speed_p (loop))
 {
 	loop_vec_info loop_vinfo;
-	vect_loop_location = find_loop_location (loop);
+	vect_location = find_loop_location (loop);
 	loop_vinfo = vect_analyze_loop (loop);
 	loop->aux = loop_vinfo;
 	if (!loop_vinfo || !LOOP_VINFO_VECTORIZABLE_P (loop_vinfo))
 	  continue;
 	vect_transform_loop (loop_vinfo);
 	num_vectorized_loops++;
 }
-vect_loop_location = UNKNOWN_LOC;
+vect_location = UNKNOWN_LOC;
 statistics_counter_event (cfun, "Vectorized loops", num_vectorized_loops);
-if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS)
+if (vect_print_dump_info (REPORT_UNVECTORIZED_LOCATIONS)
-|| (vect_print_dump_info (REPORT_VECTORIZED_LOOPS)
+|| (num_vectorized_loops > 0
-	  && num_vectorized_loops > 0))
+	  && vect_print_dump_info (REPORT_VECTORIZED_LOCATIONS)))
 fprintf (vect_dump, "vectorized %u loops in function.\n",
 	     num_vectorized_loops);
 /*  ----------- Finalize. -----------  */
-BITMAP_FREE (vect_memsyms_to_rename);
+mark_sym_for_renaming (gimple_vop (cfun));
 for (i = 1; i < vect_loops_num; i++)
 {
 loop_vec_info loop_vinfo;
 free_stmt_vec_info_vec ();
 return num_vectorized_loops > 0 ? TODO_cleanup_cfg : 0;
 }
+/*  Entry point to basic block SLP phase.  */
+static unsigned int
+execute_vect_slp (void)
+{
+basic_block bb;
+/* Fix the verbosity level if not defined explicitly by the user.  */
+vect_set_dump_settings (true);
+init_stmt_vec_info_vec ();
+FOR_EACH_BB (bb)
+{
+vect_location = find_bb_location (bb);
+if (vect_slp_analyze_bb (bb))
+{
+vect_slp_transform_bb (bb);
+if (vect_print_dump_info (REPORT_VECTORIZED_LOCATIONS))
+fprintf (vect_dump, "basic block vectorized using SLP\n");
+}
+}
+free_stmt_vec_info_vec ();
+return 0;
+}
+static bool
+gate_vect_slp (void)
+{
+/* Apply SLP either if the vectorizer is on and the user didn't specify
+whether to run SLP or not, or if the SLP flag was set by the user.  */
+return ((flag_tree_vectorize != 0 && flag_tree_slp_vectorize != 0)
+|| flag_tree_slp_vectorize == 1);
+}
+struct gimple_opt_pass pass_slp_vectorize =
+{
+{
+GIMPLE_PASS,
+"slp",                                /* name */
+gate_vect_slp,                        /* gate */
+execute_vect_slp,                     /* execute */
+NULL,                                 /* sub */
+NULL,                                 /* next */
+0,                                    /* static_pass_number */
+TV_TREE_SLP_VECTORIZATION,            /* tv_id */
+PROP_ssa | PROP_cfg,                  /* properties_required */
+0,                                    /* properties_provided */
+0,                                    /* properties_destroyed */
+0,                                    /* todo_flags_start */
+TODO_ggc_collect
+| TODO_verify_ssa
+| TODO_dump_func
+| TODO_update_ssa
+| TODO_verify_stmts                 /* todo_flags_finish */
+}
+};
 /* Increase alignment of global arrays to improve vectorization potential.
 TODO:
 - Consider also structs that have an array field.
 - Use ipa analysis to prune arrays that can't be vectorized?
 This should involve global alignment analysis and in the future also
 for (vnode = varpool_nodes_queue;
 vnode;
 vnode = vnode->next_needed)
 {
 tree vectype, decl = vnode->decl;
+tree t;
 unsigned int alignment;
-if (TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE)
+t = TREE_TYPE(decl);
-	continue;
+if (TREE_CODE (t) != ARRAY_TYPE)
-vectype = get_vectype_for_scalar_type (TREE_TYPE (TREE_TYPE (decl)));
+continue;
+vectype = get_vectype_for_scalar_type (strip_array_types (t));
 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_ALIGN (decl) = TYPE_ALIGN (vectype);
-	  DECL_USER_ALIGN (decl) = 1;
+DECL_USER_ALIGN (decl) = 1;
-	  if (dump_file)
+if (dump_file)
-	    {
+{
-	      fprintf (dump_file, "Increasing alignment of decl: ");
+fprintf (dump_file, "Increasing alignment of decl: ");
-	      print_generic_expr (dump_file, decl, TDF_SLIM);
+print_generic_expr (dump_file, decl, TDF_SLIM);
-	    }
+	      fprintf (dump_file, "\n");
-	}
+}
+}
 }
 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 */
+"increase_alignment",                 /* name */
-gate_increase_alignment,		/* gate */
+gate_increase_alignment,              /* gate */
-increase_alignment,			/* execute */
+increase_alignment,                   /* execute */
-NULL,					/* sub */
+NULL,                                 /* sub */
-NULL,					/* next */
+NULL,                                 /* next */
-0,					/* static_pass_number */
+0,                                    /* static_pass_number */
-0,					/* tv_id */
+TV_NONE,                              /* tv_id */
-0,					/* properties_required */
+0,                                    /* properties_required */
-0,					/* properties_provided */
+0,                                    /* properties_provided */
-0,					/* properties_destroyed */
+0,                                    /* properties_destroyed */
-0,					/* todo_flags_start */
+0,                                    /* todo_flags_start */
-0 					/* todo_flags_finish */
+0                                     /* todo_flags_finish */
 }
 };

Mercurial > hg > CbC > CbC_gcc

comparison gcc/tree-vectorizer.c @ 55:77e2b8dfacca gcc-4.4.5