OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [gnu-old/] [gcc-4.2.2/] [gcc/] [tree-vect-analyze.c] - Diff between revs 154 and 816

Go to most recent revision | Only display areas with differences | Details | Blame | View Log

Rev 154 Rev 816
/* Analysis Utilities for Loop Vectorization.
/* Analysis Utilities for Loop Vectorization.
   Copyright (C) 2003,2004,2005,2006, 2007 Free Software Foundation, Inc.
   Copyright (C) 2003,2004,2005,2006, 2007 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.
This file is part of GCC.
 
 
GCC is free software; you can redistribute it and/or modify it under
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
Software Foundation; either version 3, or (at your option) any later
version.
version.
 
 
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.
for more details.
 
 
You should have received a copy of the GNU General Public License
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3.  If not see
along with GCC; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  */
<http://www.gnu.org/licenses/>.  */
 
 
#include "config.h"
#include "config.h"
#include "system.h"
#include "system.h"
#include "coretypes.h"
#include "coretypes.h"
#include "tm.h"
#include "tm.h"
#include "ggc.h"
#include "ggc.h"
#include "tree.h"
#include "tree.h"
#include "target.h"
#include "target.h"
#include "basic-block.h"
#include "basic-block.h"
#include "diagnostic.h"
#include "diagnostic.h"
#include "tree-flow.h"
#include "tree-flow.h"
#include "tree-dump.h"
#include "tree-dump.h"
#include "timevar.h"
#include "timevar.h"
#include "cfgloop.h"
#include "cfgloop.h"
#include "expr.h"
#include "expr.h"
#include "optabs.h"
#include "optabs.h"
#include "params.h"
#include "params.h"
#include "tree-chrec.h"
#include "tree-chrec.h"
#include "tree-data-ref.h"
#include "tree-data-ref.h"
#include "tree-scalar-evolution.h"
#include "tree-scalar-evolution.h"
#include "tree-vectorizer.h"
#include "tree-vectorizer.h"
 
 
/* Main analysis functions.  */
/* Main analysis functions.  */
static loop_vec_info vect_analyze_loop_form (struct loop *);
static loop_vec_info vect_analyze_loop_form (struct loop *);
static bool vect_analyze_data_refs (loop_vec_info);
static bool vect_analyze_data_refs (loop_vec_info);
static bool vect_mark_stmts_to_be_vectorized (loop_vec_info);
static bool vect_mark_stmts_to_be_vectorized (loop_vec_info);
static void vect_analyze_scalar_cycles (loop_vec_info);
static void vect_analyze_scalar_cycles (loop_vec_info);
static bool vect_analyze_data_ref_accesses (loop_vec_info);
static bool vect_analyze_data_ref_accesses (loop_vec_info);
static bool vect_analyze_data_ref_dependences (loop_vec_info);
static bool vect_analyze_data_ref_dependences (loop_vec_info);
static bool vect_analyze_data_refs_alignment (loop_vec_info);
static bool vect_analyze_data_refs_alignment (loop_vec_info);
static bool vect_compute_data_refs_alignment (loop_vec_info);
static bool vect_compute_data_refs_alignment (loop_vec_info);
static bool vect_enhance_data_refs_alignment (loop_vec_info);
static bool vect_enhance_data_refs_alignment (loop_vec_info);
static bool vect_analyze_operations (loop_vec_info);
static bool vect_analyze_operations (loop_vec_info);
static bool vect_determine_vectorization_factor (loop_vec_info);
static bool vect_determine_vectorization_factor (loop_vec_info);
 
 
/* Utility functions for the analyses.  */
/* Utility functions for the analyses.  */
static bool exist_non_indexing_operands_for_use_p (tree, tree);
static bool exist_non_indexing_operands_for_use_p (tree, tree);
static void vect_mark_relevant (VEC(tree,heap) **, tree, bool, bool);
static void vect_mark_relevant (VEC(tree,heap) **, tree, bool, bool);
static bool vect_stmt_relevant_p (tree, loop_vec_info, bool *, bool *);
static bool vect_stmt_relevant_p (tree, loop_vec_info, bool *, bool *);
static tree vect_get_loop_niters (struct loop *, tree *);
static tree vect_get_loop_niters (struct loop *, tree *);
static bool vect_analyze_data_ref_dependence
static bool vect_analyze_data_ref_dependence
  (struct data_dependence_relation *, loop_vec_info);
  (struct data_dependence_relation *, loop_vec_info);
static bool vect_compute_data_ref_alignment (struct data_reference *);
static bool vect_compute_data_ref_alignment (struct data_reference *);
static bool vect_analyze_data_ref_access (struct data_reference *);
static bool vect_analyze_data_ref_access (struct data_reference *);
static bool vect_can_advance_ivs_p (loop_vec_info);
static bool vect_can_advance_ivs_p (loop_vec_info);
static void vect_update_misalignment_for_peel
static void vect_update_misalignment_for_peel
  (struct data_reference *, struct data_reference *, int npeel);
  (struct data_reference *, struct data_reference *, int npeel);
 
 
 
 
/* Function vect_determine_vectorization_factor
/* Function vect_determine_vectorization_factor
 
 
   Determine the vectorization factor (VF). VF is the number of data elements
   Determine the vectorization factor (VF). VF is the number of data elements
   that are operated upon in parallel in a single iteration of the vectorized
   that are operated upon in parallel in a single iteration of the vectorized
   loop. For example, when vectorizing a loop that operates on 4byte elements,
   loop. For example, when vectorizing a loop that operates on 4byte elements,
   on a target with vector size (VS) 16byte, the VF is set to 4, since 4
   on a target with vector size (VS) 16byte, the VF is set to 4, since 4
   elements can fit in a single vector register.
   elements can fit in a single vector register.
 
 
   We currently support vectorization of loops in which all types operated upon
   We currently support vectorization of loops in which all types operated upon
   are of the same size. Therefore this function currently sets VF according to
   are of the same size. Therefore this function currently sets VF according to
   the size of the types operated upon, and fails if there are multiple sizes
   the size of the types operated upon, and fails if there are multiple sizes
   in the loop.
   in the loop.
 
 
   VF is also the factor by which the loop iterations are strip-mined, e.g.:
   VF is also the factor by which the loop iterations are strip-mined, e.g.:
   original loop:
   original loop:
        for (i=0; i<N; i++){
        for (i=0; i<N; i++){
          a[i] = b[i] + c[i];
          a[i] = b[i] + c[i];
        }
        }
 
 
   vectorized loop:
   vectorized loop:
        for (i=0; i<N; i+=VF){
        for (i=0; i<N; i+=VF){
          a[i:VF] = b[i:VF] + c[i:VF];
          a[i:VF] = b[i:VF] + c[i:VF];
        }
        }
*/
*/
 
 
static bool
static bool
vect_determine_vectorization_factor (loop_vec_info loop_vinfo)
vect_determine_vectorization_factor (loop_vec_info loop_vinfo)
{
{
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
  basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
  int nbbs = loop->num_nodes;
  int nbbs = loop->num_nodes;
  block_stmt_iterator si;
  block_stmt_iterator si;
  unsigned int vectorization_factor = 0;
  unsigned int vectorization_factor = 0;
  int i;
  int i;
  tree scalar_type;
  tree scalar_type;
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "=== vect_determine_vectorization_factor ===");
    fprintf (vect_dump, "=== vect_determine_vectorization_factor ===");
 
 
  for (i = 0; i < nbbs; i++)
  for (i = 0; i < nbbs; i++)
    {
    {
      basic_block bb = bbs[i];
      basic_block bb = bbs[i];
 
 
      for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
      for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
        {
        {
          tree stmt = bsi_stmt (si);
          tree stmt = bsi_stmt (si);
          unsigned int nunits;
          unsigned int nunits;
          stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
          stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
          tree vectype;
          tree vectype;
 
 
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            {
            {
              fprintf (vect_dump, "==> examining statement: ");
              fprintf (vect_dump, "==> examining statement: ");
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
            }
            }
 
 
          gcc_assert (stmt_info);
          gcc_assert (stmt_info);
          /* skip stmts which do not need to be vectorized.  */
          /* skip stmts which do not need to be vectorized.  */
          if (!STMT_VINFO_RELEVANT_P (stmt_info)
          if (!STMT_VINFO_RELEVANT_P (stmt_info)
              && !STMT_VINFO_LIVE_P (stmt_info))
              && !STMT_VINFO_LIVE_P (stmt_info))
            {
            {
              if (vect_print_dump_info (REPORT_DETAILS))
              if (vect_print_dump_info (REPORT_DETAILS))
                fprintf (vect_dump, "skip.");
                fprintf (vect_dump, "skip.");
              continue;
              continue;
            }
            }
 
 
          if (VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))))
          if (VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))))
            {
            {
              if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
              if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                {
                {
                  fprintf (vect_dump, "not vectorized: vector stmt in loop:");
                  fprintf (vect_dump, "not vectorized: vector stmt in loop:");
                  print_generic_expr (vect_dump, stmt, TDF_SLIM);
                  print_generic_expr (vect_dump, stmt, TDF_SLIM);
                }
                }
              return false;
              return false;
            }
            }
 
 
          if (STMT_VINFO_VECTYPE (stmt_info))
          if (STMT_VINFO_VECTYPE (stmt_info))
            {
            {
              vectype = STMT_VINFO_VECTYPE (stmt_info);
              vectype = STMT_VINFO_VECTYPE (stmt_info);
              scalar_type = TREE_TYPE (vectype);
              scalar_type = TREE_TYPE (vectype);
            }
            }
          else
          else
            {
            {
              if (STMT_VINFO_DATA_REF (stmt_info))
              if (STMT_VINFO_DATA_REF (stmt_info))
                scalar_type =
                scalar_type =
                        TREE_TYPE (DR_REF (STMT_VINFO_DATA_REF (stmt_info)));
                        TREE_TYPE (DR_REF (STMT_VINFO_DATA_REF (stmt_info)));
              else if (TREE_CODE (stmt) == MODIFY_EXPR)
              else if (TREE_CODE (stmt) == MODIFY_EXPR)
                scalar_type = TREE_TYPE (TREE_OPERAND (stmt, 0));
                scalar_type = TREE_TYPE (TREE_OPERAND (stmt, 0));
              else
              else
                scalar_type = TREE_TYPE (stmt);
                scalar_type = TREE_TYPE (stmt);
 
 
              if (vect_print_dump_info (REPORT_DETAILS))
              if (vect_print_dump_info (REPORT_DETAILS))
                {
                {
                  fprintf (vect_dump, "get vectype for scalar type:  ");
                  fprintf (vect_dump, "get vectype for scalar type:  ");
                  print_generic_expr (vect_dump, scalar_type, TDF_SLIM);
                  print_generic_expr (vect_dump, scalar_type, TDF_SLIM);
                }
                }
 
 
              vectype = get_vectype_for_scalar_type (scalar_type);
              vectype = get_vectype_for_scalar_type (scalar_type);
              if (!vectype)
              if (!vectype)
                {
                {
                  if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                  if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                    {
                    {
                      fprintf (vect_dump,
                      fprintf (vect_dump,
                               "not vectorized: unsupported data-type ");
                               "not vectorized: unsupported data-type ");
                      print_generic_expr (vect_dump, scalar_type, TDF_SLIM);
                      print_generic_expr (vect_dump, scalar_type, TDF_SLIM);
                    }
                    }
                  return false;
                  return false;
                }
                }
              STMT_VINFO_VECTYPE (stmt_info) = vectype;
              STMT_VINFO_VECTYPE (stmt_info) = vectype;
            }
            }
 
 
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            {
            {
              fprintf (vect_dump, "vectype: ");
              fprintf (vect_dump, "vectype: ");
              print_generic_expr (vect_dump, vectype, TDF_SLIM);
              print_generic_expr (vect_dump, vectype, TDF_SLIM);
            }
            }
 
 
          nunits = TYPE_VECTOR_SUBPARTS (vectype);
          nunits = TYPE_VECTOR_SUBPARTS (vectype);
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            fprintf (vect_dump, "nunits = %d", nunits);
            fprintf (vect_dump, "nunits = %d", nunits);
 
 
          if (vectorization_factor)
          if (vectorization_factor)
            {
            {
              /* FORNOW: don't allow mixed units.
              /* FORNOW: don't allow mixed units.
                 This restriction will be relaxed in the future.  */
                 This restriction will be relaxed in the future.  */
              if (nunits != vectorization_factor)
              if (nunits != vectorization_factor)
                {
                {
                  if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                  if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                    fprintf (vect_dump, "not vectorized: mixed data-types");
                    fprintf (vect_dump, "not vectorized: mixed data-types");
                  return false;
                  return false;
                }
                }
            }
            }
          else
          else
            vectorization_factor = nunits;
            vectorization_factor = nunits;
 
 
          gcc_assert (GET_MODE_SIZE (TYPE_MODE (scalar_type))
          gcc_assert (GET_MODE_SIZE (TYPE_MODE (scalar_type))
                        * vectorization_factor == UNITS_PER_SIMD_WORD);
                        * vectorization_factor == UNITS_PER_SIMD_WORD);
        }
        }
    }
    }
 
 
  /* TODO: Analyze cost. Decide if worth while to vectorize.  */
  /* TODO: Analyze cost. Decide if worth while to vectorize.  */
 
 
  if (vectorization_factor <= 1)
  if (vectorization_factor <= 1)
    {
    {
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
        fprintf (vect_dump, "not vectorized: unsupported data-type");
        fprintf (vect_dump, "not vectorized: unsupported data-type");
      return false;
      return false;
    }
    }
  LOOP_VINFO_VECT_FACTOR (loop_vinfo) = vectorization_factor;
  LOOP_VINFO_VECT_FACTOR (loop_vinfo) = vectorization_factor;
 
 
  return true;
  return true;
}
}
 
 
 
 
/* Function vect_analyze_operations.
/* Function vect_analyze_operations.
 
 
   Scan the loop stmts and make sure they are all vectorizable.  */
   Scan the loop stmts and make sure they are all vectorizable.  */
 
 
static bool
static bool
vect_analyze_operations (loop_vec_info loop_vinfo)
vect_analyze_operations (loop_vec_info loop_vinfo)
{
{
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
  basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
  int nbbs = loop->num_nodes;
  int nbbs = loop->num_nodes;
  block_stmt_iterator si;
  block_stmt_iterator si;
  unsigned int vectorization_factor = 0;
  unsigned int vectorization_factor = 0;
  int i;
  int i;
  bool ok;
  bool ok;
  tree phi;
  tree phi;
  stmt_vec_info stmt_info;
  stmt_vec_info stmt_info;
  bool need_to_vectorize = false;
  bool need_to_vectorize = false;
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "=== vect_analyze_operations ===");
    fprintf (vect_dump, "=== vect_analyze_operations ===");
 
 
  gcc_assert (LOOP_VINFO_VECT_FACTOR (loop_vinfo));
  gcc_assert (LOOP_VINFO_VECT_FACTOR (loop_vinfo));
  vectorization_factor = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
  vectorization_factor = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
 
 
  for (i = 0; i < nbbs; i++)
  for (i = 0; i < nbbs; i++)
    {
    {
      basic_block bb = bbs[i];
      basic_block bb = bbs[i];
 
 
      for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
      for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
        {
        {
          stmt_info = vinfo_for_stmt (phi);
          stmt_info = vinfo_for_stmt (phi);
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            {
            {
              fprintf (vect_dump, "examining phi: ");
              fprintf (vect_dump, "examining phi: ");
              print_generic_expr (vect_dump, phi, TDF_SLIM);
              print_generic_expr (vect_dump, phi, TDF_SLIM);
            }
            }
 
 
          gcc_assert (stmt_info);
          gcc_assert (stmt_info);
 
 
          if (STMT_VINFO_LIVE_P (stmt_info))
          if (STMT_VINFO_LIVE_P (stmt_info))
            {
            {
              /* FORNOW: not yet supported.  */
              /* FORNOW: not yet supported.  */
              if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
              if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                fprintf (vect_dump, "not vectorized: value used after loop.");
                fprintf (vect_dump, "not vectorized: value used after loop.");
            return false;
            return false;
          }
          }
 
 
          if (STMT_VINFO_RELEVANT_P (stmt_info))
          if (STMT_VINFO_RELEVANT_P (stmt_info))
            {
            {
              /* Most likely a reduction-like computation that is used
              /* Most likely a reduction-like computation that is used
                 in the loop.  */
                 in the loop.  */
              if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
              if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                fprintf (vect_dump, "not vectorized: unsupported pattern.");
                fprintf (vect_dump, "not vectorized: unsupported pattern.");
             return false;
             return false;
            }
            }
        }
        }
 
 
      for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
      for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
        {
        {
          tree stmt = bsi_stmt (si);
          tree stmt = bsi_stmt (si);
          stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
          stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
 
 
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            {
            {
              fprintf (vect_dump, "==> examining statement: ");
              fprintf (vect_dump, "==> examining statement: ");
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
            }
            }
 
 
          gcc_assert (stmt_info);
          gcc_assert (stmt_info);
 
 
          /* skip stmts which do not need to be vectorized.
          /* skip stmts which do not need to be vectorized.
             this is expected to include:
             this is expected to include:
             - the COND_EXPR which is the loop exit condition
             - the COND_EXPR which is the loop exit condition
             - any LABEL_EXPRs in the loop
             - any LABEL_EXPRs in the loop
             - computations that are used only for array indexing or loop
             - computations that are used only for array indexing or loop
             control  */
             control  */
 
 
          if (!STMT_VINFO_RELEVANT_P (stmt_info)
          if (!STMT_VINFO_RELEVANT_P (stmt_info)
              && !STMT_VINFO_LIVE_P (stmt_info))
              && !STMT_VINFO_LIVE_P (stmt_info))
            {
            {
              if (vect_print_dump_info (REPORT_DETAILS))
              if (vect_print_dump_info (REPORT_DETAILS))
                fprintf (vect_dump, "irrelevant.");
                fprintf (vect_dump, "irrelevant.");
              continue;
              continue;
            }
            }
 
 
          if (STMT_VINFO_RELEVANT_P (stmt_info))
          if (STMT_VINFO_RELEVANT_P (stmt_info))
            {
            {
              gcc_assert (!VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))));
              gcc_assert (!VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))));
              gcc_assert (STMT_VINFO_VECTYPE (stmt_info));
              gcc_assert (STMT_VINFO_VECTYPE (stmt_info));
 
 
              ok = (vectorizable_operation (stmt, NULL, NULL)
              ok = (vectorizable_operation (stmt, NULL, NULL)
                    || vectorizable_assignment (stmt, NULL, NULL)
                    || vectorizable_assignment (stmt, NULL, NULL)
                    || vectorizable_load (stmt, NULL, NULL)
                    || vectorizable_load (stmt, NULL, NULL)
                    || vectorizable_store (stmt, NULL, NULL)
                    || vectorizable_store (stmt, NULL, NULL)
                    || vectorizable_condition (stmt, NULL, NULL));
                    || vectorizable_condition (stmt, NULL, NULL));
 
 
              if (!ok)
              if (!ok)
                {
                {
                  if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                  if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                    {
                    {
                      fprintf (vect_dump,
                      fprintf (vect_dump,
                               "not vectorized: relevant stmt not supported: ");
                               "not vectorized: relevant stmt not supported: ");
                      print_generic_expr (vect_dump, stmt, TDF_SLIM);
                      print_generic_expr (vect_dump, stmt, TDF_SLIM);
                    }
                    }
                  return false;
                  return false;
                }
                }
              need_to_vectorize = true;
              need_to_vectorize = true;
            }
            }
 
 
          if (STMT_VINFO_LIVE_P (stmt_info))
          if (STMT_VINFO_LIVE_P (stmt_info))
            {
            {
              ok = vectorizable_reduction (stmt, NULL, NULL);
              ok = vectorizable_reduction (stmt, NULL, NULL);
 
 
              if (ok)
              if (ok)
                need_to_vectorize = true;
                need_to_vectorize = true;
              else
              else
                ok = vectorizable_live_operation (stmt, NULL, NULL);
                ok = vectorizable_live_operation (stmt, NULL, NULL);
 
 
              if (!ok)
              if (!ok)
                {
                {
                  if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                  if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                    {
                    {
                      fprintf (vect_dump,
                      fprintf (vect_dump,
                               "not vectorized: live stmt not supported: ");
                               "not vectorized: live stmt not supported: ");
                      print_generic_expr (vect_dump, stmt, TDF_SLIM);
                      print_generic_expr (vect_dump, stmt, TDF_SLIM);
                    }
                    }
                  return false;
                  return false;
                }
                }
            }
            }
        } /* stmts in bb */
        } /* stmts in bb */
    } /* bbs */
    } /* bbs */
 
 
  /* TODO: Analyze cost. Decide if worth while to vectorize.  */
  /* TODO: Analyze cost. Decide if worth while to vectorize.  */
 
 
  /* All operations in the loop are either irrelevant (deal with loop
  /* All operations in the loop are either irrelevant (deal with loop
     control, or dead), or only used outside the loop and can be moved
     control, or dead), or only used outside the loop and can be moved
     out of the loop (e.g. invariants, inductions).  The loop can be
     out of the loop (e.g. invariants, inductions).  The loop can be
     optimized away by scalar optimizations.  We're better off not
     optimized away by scalar optimizations.  We're better off not
     touching this loop.  */
     touching this loop.  */
  if (!need_to_vectorize)
  if (!need_to_vectorize)
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump,
        fprintf (vect_dump,
                 "All the computation can be taken out of the loop.");
                 "All the computation can be taken out of the loop.");
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
        fprintf (vect_dump,
        fprintf (vect_dump,
                 "not vectorized: redundant loop. no profit to vectorize.");
                 "not vectorized: redundant loop. no profit to vectorize.");
      return false;
      return false;
    }
    }
 
 
  if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
  if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
      && vect_print_dump_info (REPORT_DETAILS))
      && vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump,
    fprintf (vect_dump,
        "vectorization_factor = %d, niters = " HOST_WIDE_INT_PRINT_DEC,
        "vectorization_factor = %d, niters = " HOST_WIDE_INT_PRINT_DEC,
        vectorization_factor, LOOP_VINFO_INT_NITERS (loop_vinfo));
        vectorization_factor, LOOP_VINFO_INT_NITERS (loop_vinfo));
 
 
  if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
  if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
      && LOOP_VINFO_INT_NITERS (loop_vinfo) < vectorization_factor)
      && LOOP_VINFO_INT_NITERS (loop_vinfo) < vectorization_factor)
    {
    {
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
        fprintf (vect_dump, "not vectorized: iteration count too small.");
        fprintf (vect_dump, "not vectorized: iteration count too small.");
      return false;
      return false;
    }
    }
 
 
  if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
  if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
      || LOOP_VINFO_INT_NITERS (loop_vinfo) % vectorization_factor != 0
      || LOOP_VINFO_INT_NITERS (loop_vinfo) % vectorization_factor != 0
      || LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo))
      || LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo))
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "epilog loop required.");
        fprintf (vect_dump, "epilog loop required.");
      if (!vect_can_advance_ivs_p (loop_vinfo))
      if (!vect_can_advance_ivs_p (loop_vinfo))
        {
        {
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
            fprintf (vect_dump,
            fprintf (vect_dump,
                     "not vectorized: can't create epilog loop 1.");
                     "not vectorized: can't create epilog loop 1.");
          return false;
          return false;
        }
        }
      if (!slpeel_can_duplicate_loop_p (loop, loop->single_exit))
      if (!slpeel_can_duplicate_loop_p (loop, loop->single_exit))
        {
        {
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
            fprintf (vect_dump,
            fprintf (vect_dump,
                     "not vectorized: can't create epilog loop 2.");
                     "not vectorized: can't create epilog loop 2.");
          return false;
          return false;
        }
        }
    }
    }
 
 
  return true;
  return true;
}
}
 
 
 
 
/* Function exist_non_indexing_operands_for_use_p
/* Function exist_non_indexing_operands_for_use_p
 
 
   USE is one of the uses attached to STMT. Check if USE is
   USE is one of the uses attached to STMT. Check if USE is
   used in STMT for anything other than indexing an array.  */
   used in STMT for anything other than indexing an array.  */
 
 
static bool
static bool
exist_non_indexing_operands_for_use_p (tree use, tree stmt)
exist_non_indexing_operands_for_use_p (tree use, tree stmt)
{
{
  tree operand;
  tree operand;
  stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
  stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
 
 
  /* USE corresponds to some operand in STMT. If there is no data
  /* USE corresponds to some operand in STMT. If there is no data
     reference in STMT, then any operand that corresponds to USE
     reference in STMT, then any operand that corresponds to USE
     is not indexing an array.  */
     is not indexing an array.  */
  if (!STMT_VINFO_DATA_REF (stmt_info))
  if (!STMT_VINFO_DATA_REF (stmt_info))
    return true;
    return true;
 
 
  /* STMT has a data_ref. FORNOW this means that its of one of
  /* STMT has a data_ref. FORNOW this means that its of one of
     the following forms:
     the following forms:
     -1- ARRAY_REF = var
     -1- ARRAY_REF = var
     -2- var = ARRAY_REF
     -2- var = ARRAY_REF
     (This should have been verified in analyze_data_refs).
     (This should have been verified in analyze_data_refs).
 
 
     'var' in the second case corresponds to a def, not a use,
     'var' in the second case corresponds to a def, not a use,
     so USE cannot correspond to any operands that are not used
     so USE cannot correspond to any operands that are not used
     for array indexing.
     for array indexing.
 
 
     Therefore, all we need to check is if STMT falls into the
     Therefore, all we need to check is if STMT falls into the
     first case, and whether var corresponds to USE.  */
     first case, and whether var corresponds to USE.  */
 
 
  if (TREE_CODE (TREE_OPERAND (stmt, 0)) == SSA_NAME)
  if (TREE_CODE (TREE_OPERAND (stmt, 0)) == SSA_NAME)
    return false;
    return false;
 
 
  operand = TREE_OPERAND (stmt, 1);
  operand = TREE_OPERAND (stmt, 1);
 
 
  if (TREE_CODE (operand) != SSA_NAME)
  if (TREE_CODE (operand) != SSA_NAME)
    return false;
    return false;
 
 
  if (operand == use)
  if (operand == use)
    return true;
    return true;
 
 
  return false;
  return false;
}
}
 
 
 
 
/* Function vect_analyze_scalar_cycles.
/* Function vect_analyze_scalar_cycles.
 
 
   Examine the cross iteration def-use cycles of scalar variables, by
   Examine the cross iteration def-use cycles of scalar variables, by
   analyzing the loop (scalar) PHIs; Classify each cycle as one of the
   analyzing the loop (scalar) PHIs; Classify each cycle as one of the
   following: invariant, induction, reduction, unknown.
   following: invariant, induction, reduction, unknown.
 
 
   Some forms of scalar cycles are not yet supported.
   Some forms of scalar cycles are not yet supported.
 
 
   Example1: reduction: (unsupported yet)
   Example1: reduction: (unsupported yet)
 
 
              loop1:
              loop1:
              for (i=0; i<N; i++)
              for (i=0; i<N; i++)
                 sum += a[i];
                 sum += a[i];
 
 
   Example2: induction: (unsupported yet)
   Example2: induction: (unsupported yet)
 
 
              loop2:
              loop2:
              for (i=0; i<N; i++)
              for (i=0; i<N; i++)
                 a[i] = i;
                 a[i] = i;
 
 
   Note: the following loop *is* vectorizable:
   Note: the following loop *is* vectorizable:
 
 
              loop3:
              loop3:
              for (i=0; i<N; i++)
              for (i=0; i<N; i++)
                 a[i] = b[i];
                 a[i] = b[i];
 
 
         even though it has a def-use cycle caused by the induction variable i:
         even though it has a def-use cycle caused by the induction variable i:
 
 
              loop: i_2 = PHI (i_0, i_1)
              loop: i_2 = PHI (i_0, i_1)
                    a[i_2] = ...;
                    a[i_2] = ...;
                    i_1 = i_2 + 1;
                    i_1 = i_2 + 1;
                    GOTO loop;
                    GOTO loop;
 
 
         because the def-use cycle in loop3 is considered "not relevant" - i.e.,
         because the def-use cycle in loop3 is considered "not relevant" - i.e.,
         it does not need to be vectorized because it is only used for array
         it does not need to be vectorized because it is only used for array
         indexing (see 'mark_stmts_to_be_vectorized'). The def-use cycle in
         indexing (see 'mark_stmts_to_be_vectorized'). The def-use cycle in
         loop2 on the other hand is relevant (it is being written to memory).
         loop2 on the other hand is relevant (it is being written to memory).
*/
*/
 
 
static void
static void
vect_analyze_scalar_cycles (loop_vec_info loop_vinfo)
vect_analyze_scalar_cycles (loop_vec_info loop_vinfo)
{
{
  tree phi;
  tree phi;
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  basic_block bb = loop->header;
  basic_block bb = loop->header;
  tree dummy;
  tree dummy;
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "=== vect_analyze_scalar_cycles ===");
    fprintf (vect_dump, "=== vect_analyze_scalar_cycles ===");
 
 
  for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
  for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
    {
    {
      tree access_fn = NULL;
      tree access_fn = NULL;
      tree def = PHI_RESULT (phi);
      tree def = PHI_RESULT (phi);
      stmt_vec_info stmt_vinfo = vinfo_for_stmt (phi);
      stmt_vec_info stmt_vinfo = vinfo_for_stmt (phi);
      tree reduc_stmt;
      tree reduc_stmt;
 
 
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        {
        {
          fprintf (vect_dump, "Analyze phi: ");
          fprintf (vect_dump, "Analyze phi: ");
          print_generic_expr (vect_dump, phi, TDF_SLIM);
          print_generic_expr (vect_dump, phi, TDF_SLIM);
        }
        }
 
 
      /* Skip virtual phi's. The data dependences that are associated with
      /* Skip virtual phi's. The data dependences that are associated with
         virtual defs/uses (i.e., memory accesses) are analyzed elsewhere.  */
         virtual defs/uses (i.e., memory accesses) are analyzed elsewhere.  */
 
 
      if (!is_gimple_reg (SSA_NAME_VAR (def)))
      if (!is_gimple_reg (SSA_NAME_VAR (def)))
        {
        {
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            fprintf (vect_dump, "virtual phi. skip.");
            fprintf (vect_dump, "virtual phi. skip.");
          continue;
          continue;
        }
        }
 
 
      STMT_VINFO_DEF_TYPE (stmt_vinfo) = vect_unknown_def_type;
      STMT_VINFO_DEF_TYPE (stmt_vinfo) = vect_unknown_def_type;
 
 
      /* Analyze the evolution function.  */
      /* Analyze the evolution function.  */
 
 
      access_fn = analyze_scalar_evolution (loop, def);
      access_fn = analyze_scalar_evolution (loop, def);
 
 
      if (!access_fn)
      if (!access_fn)
        continue;
        continue;
 
 
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        {
        {
           fprintf (vect_dump, "Access function of PHI: ");
           fprintf (vect_dump, "Access function of PHI: ");
           print_generic_expr (vect_dump, access_fn, TDF_SLIM);
           print_generic_expr (vect_dump, access_fn, TDF_SLIM);
        }
        }
 
 
      if (vect_is_simple_iv_evolution (loop->num, access_fn, &dummy, &dummy))
      if (vect_is_simple_iv_evolution (loop->num, access_fn, &dummy, &dummy))
        {
        {
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            fprintf (vect_dump, "Detected induction.");
            fprintf (vect_dump, "Detected induction.");
          STMT_VINFO_DEF_TYPE (stmt_vinfo) = vect_induction_def;
          STMT_VINFO_DEF_TYPE (stmt_vinfo) = vect_induction_def;
          continue;
          continue;
        }
        }
 
 
      /* TODO: handle invariant phis  */
      /* TODO: handle invariant phis  */
 
 
      reduc_stmt = vect_is_simple_reduction (loop, phi);
      reduc_stmt = vect_is_simple_reduction (loop, phi);
      if (reduc_stmt)
      if (reduc_stmt)
        {
        {
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            fprintf (vect_dump, "Detected reduction.");
            fprintf (vect_dump, "Detected reduction.");
          STMT_VINFO_DEF_TYPE (stmt_vinfo) = vect_reduction_def;
          STMT_VINFO_DEF_TYPE (stmt_vinfo) = vect_reduction_def;
          STMT_VINFO_DEF_TYPE (vinfo_for_stmt (reduc_stmt)) =
          STMT_VINFO_DEF_TYPE (vinfo_for_stmt (reduc_stmt)) =
                                                        vect_reduction_def;
                                                        vect_reduction_def;
        }
        }
      else
      else
        if (vect_print_dump_info (REPORT_DETAILS))
        if (vect_print_dump_info (REPORT_DETAILS))
          fprintf (vect_dump, "Unknown def-use cycle pattern.");
          fprintf (vect_dump, "Unknown def-use cycle pattern.");
 
 
    }
    }
 
 
  return;
  return;
}
}
 
 
 
 
/* Function vect_analyze_data_ref_dependence.
/* Function vect_analyze_data_ref_dependence.
 
 
   Return TRUE if there (might) exist a dependence between a memory-reference
   Return TRUE if there (might) exist a dependence between a memory-reference
   DRA and a memory-reference DRB.  */
   DRA and a memory-reference DRB.  */
 
 
static bool
static bool
vect_analyze_data_ref_dependence (struct data_dependence_relation *ddr,
vect_analyze_data_ref_dependence (struct data_dependence_relation *ddr,
                                  loop_vec_info loop_vinfo)
                                  loop_vec_info loop_vinfo)
{
{
  unsigned int i;
  unsigned int i;
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  int vectorization_factor = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
  int vectorization_factor = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
  struct data_reference *dra = DDR_A (ddr);
  struct data_reference *dra = DDR_A (ddr);
  struct data_reference *drb = DDR_B (ddr);
  struct data_reference *drb = DDR_B (ddr);
  stmt_vec_info stmtinfo_a = vinfo_for_stmt (DR_STMT (dra));
  stmt_vec_info stmtinfo_a = vinfo_for_stmt (DR_STMT (dra));
  stmt_vec_info stmtinfo_b = vinfo_for_stmt (DR_STMT (drb));
  stmt_vec_info stmtinfo_b = vinfo_for_stmt (DR_STMT (drb));
  lambda_vector dist_v;
  lambda_vector dist_v;
  unsigned int loop_depth;
  unsigned int loop_depth;
 
 
  if (DDR_ARE_DEPENDENT (ddr) == chrec_known)
  if (DDR_ARE_DEPENDENT (ddr) == chrec_known)
    return false;
    return false;
 
 
  if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know)
  if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know)
    {
    {
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
        {
        {
          fprintf (vect_dump,
          fprintf (vect_dump,
                   "not vectorized: can't determine dependence between ");
                   "not vectorized: can't determine dependence between ");
          print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
          print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
          fprintf (vect_dump, " and ");
          fprintf (vect_dump, " and ");
          print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
          print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
        }
        }
      return true;
      return true;
    }
    }
 
 
  if (DDR_NUM_DIST_VECTS (ddr) == 0)
  if (DDR_NUM_DIST_VECTS (ddr) == 0)
    {
    {
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
        {
        {
          fprintf (vect_dump, "not vectorized: bad dist vector for ");
          fprintf (vect_dump, "not vectorized: bad dist vector for ");
          print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
          print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
          fprintf (vect_dump, " and ");
          fprintf (vect_dump, " and ");
          print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
          print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
        }
        }
      return true;
      return true;
    }
    }
 
 
  loop_depth = index_in_loop_nest (loop->num, DDR_LOOP_NEST (ddr));
  loop_depth = index_in_loop_nest (loop->num, DDR_LOOP_NEST (ddr));
  for (i = 0; VEC_iterate (lambda_vector, DDR_DIST_VECTS (ddr), i, dist_v); i++)
  for (i = 0; VEC_iterate (lambda_vector, DDR_DIST_VECTS (ddr), i, dist_v); i++)
    {
    {
      int dist = dist_v[loop_depth];
      int dist = dist_v[loop_depth];
 
 
      if (vect_print_dump_info (REPORT_DR_DETAILS))
      if (vect_print_dump_info (REPORT_DR_DETAILS))
        fprintf (vect_dump, "dependence distance  = %d.", dist);
        fprintf (vect_dump, "dependence distance  = %d.", dist);
 
 
      /* Same loop iteration.  */
      /* Same loop iteration.  */
      if (dist % vectorization_factor == 0)
      if (dist % vectorization_factor == 0)
        {
        {
          /* Two references with distance zero have the same alignment.  */
          /* Two references with distance zero have the same alignment.  */
          VEC_safe_push (dr_p, heap, STMT_VINFO_SAME_ALIGN_REFS (stmtinfo_a), drb);
          VEC_safe_push (dr_p, heap, STMT_VINFO_SAME_ALIGN_REFS (stmtinfo_a), drb);
          VEC_safe_push (dr_p, heap, STMT_VINFO_SAME_ALIGN_REFS (stmtinfo_b), dra);
          VEC_safe_push (dr_p, heap, STMT_VINFO_SAME_ALIGN_REFS (stmtinfo_b), dra);
          if (vect_print_dump_info (REPORT_ALIGNMENT))
          if (vect_print_dump_info (REPORT_ALIGNMENT))
            fprintf (vect_dump, "accesses have the same alignment.");
            fprintf (vect_dump, "accesses have the same alignment.");
          if (vect_print_dump_info (REPORT_DR_DETAILS))
          if (vect_print_dump_info (REPORT_DR_DETAILS))
            {
            {
              fprintf (vect_dump, "dependence distance modulo vf == 0 between ");
              fprintf (vect_dump, "dependence distance modulo vf == 0 between ");
              print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
              print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
              fprintf (vect_dump, " and ");
              fprintf (vect_dump, " and ");
              print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
              print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
            }
            }
          continue;
          continue;
        }
        }
 
 
      if (abs (dist) >= vectorization_factor)
      if (abs (dist) >= vectorization_factor)
        {
        {
          /* Dependence distance does not create dependence, as far as vectorization
          /* Dependence distance does not create dependence, as far as vectorization
             is concerned, in this case.  */
             is concerned, in this case.  */
          if (vect_print_dump_info (REPORT_DR_DETAILS))
          if (vect_print_dump_info (REPORT_DR_DETAILS))
            fprintf (vect_dump, "dependence distance >= VF.");
            fprintf (vect_dump, "dependence distance >= VF.");
          continue;
          continue;
        }
        }
 
 
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
        {
        {
          fprintf (vect_dump,
          fprintf (vect_dump,
                   "not vectorized: possible dependence between data-refs ");
                   "not vectorized: possible dependence between data-refs ");
          print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
          print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
          fprintf (vect_dump, " and ");
          fprintf (vect_dump, " and ");
          print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
          print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
        }
        }
 
 
      return true;
      return true;
    }
    }
 
 
  return false;
  return false;
}
}
 
 
 
 
/* Function vect_analyze_data_ref_dependences.
/* Function vect_analyze_data_ref_dependences.
 
 
   Examine all the data references in the loop, and make sure there do not
   Examine all the data references in the loop, and make sure there do not
   exist any data dependences between them.  */
   exist any data dependences between them.  */
 
 
static bool
static bool
vect_analyze_data_ref_dependences (loop_vec_info loop_vinfo)
vect_analyze_data_ref_dependences (loop_vec_info loop_vinfo)
{
{
  unsigned int i;
  unsigned int i;
  VEC (ddr_p, heap) *ddrs = LOOP_VINFO_DDRS (loop_vinfo);
  VEC (ddr_p, heap) *ddrs = LOOP_VINFO_DDRS (loop_vinfo);
  struct data_dependence_relation *ddr;
  struct data_dependence_relation *ddr;
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "=== vect_analyze_dependences ===");
    fprintf (vect_dump, "=== vect_analyze_dependences ===");
 
 
  for (i = 0; VEC_iterate (ddr_p, ddrs, i, ddr); i++)
  for (i = 0; VEC_iterate (ddr_p, ddrs, i, ddr); i++)
    if (vect_analyze_data_ref_dependence (ddr, loop_vinfo))
    if (vect_analyze_data_ref_dependence (ddr, loop_vinfo))
      return false;
      return false;
 
 
  return true;
  return true;
}
}
 
 
 
 
/* Function vect_compute_data_ref_alignment
/* Function vect_compute_data_ref_alignment
 
 
   Compute the misalignment of the data reference DR.
   Compute the misalignment of the data reference DR.
 
 
   Output:
   Output:
   1. If during the misalignment computation it is found that the data reference
   1. If during the misalignment computation it is found that the data reference
      cannot be vectorized then false is returned.
      cannot be vectorized then false is returned.
   2. DR_MISALIGNMENT (DR) is defined.
   2. DR_MISALIGNMENT (DR) is defined.
 
 
   FOR NOW: No analysis is actually performed. Misalignment is calculated
   FOR NOW: No analysis is actually performed. Misalignment is calculated
   only for trivial cases. TODO.  */
   only for trivial cases. TODO.  */
 
 
static bool
static bool
vect_compute_data_ref_alignment (struct data_reference *dr)
vect_compute_data_ref_alignment (struct data_reference *dr)
{
{
  tree stmt = DR_STMT (dr);
  tree stmt = DR_STMT (dr);
  stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
  stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
  tree ref = DR_REF (dr);
  tree ref = DR_REF (dr);
  tree vectype;
  tree vectype;
  tree base, base_addr;
  tree base, base_addr;
  bool base_aligned;
  bool base_aligned;
  tree misalign;
  tree misalign;
  tree aligned_to, alignment;
  tree aligned_to, alignment;
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "vect_compute_data_ref_alignment:");
    fprintf (vect_dump, "vect_compute_data_ref_alignment:");
 
 
  /* Initialize misalignment to unknown.  */
  /* Initialize misalignment to unknown.  */
  DR_MISALIGNMENT (dr) = -1;
  DR_MISALIGNMENT (dr) = -1;
 
 
  misalign = DR_OFFSET_MISALIGNMENT (dr);
  misalign = DR_OFFSET_MISALIGNMENT (dr);
  aligned_to = DR_ALIGNED_TO (dr);
  aligned_to = DR_ALIGNED_TO (dr);
  base_addr = DR_BASE_ADDRESS (dr);
  base_addr = DR_BASE_ADDRESS (dr);
  base = build_fold_indirect_ref (base_addr);
  base = build_fold_indirect_ref (base_addr);
  vectype = STMT_VINFO_VECTYPE (stmt_info);
  vectype = STMT_VINFO_VECTYPE (stmt_info);
  alignment = ssize_int (TYPE_ALIGN (vectype)/BITS_PER_UNIT);
  alignment = ssize_int (TYPE_ALIGN (vectype)/BITS_PER_UNIT);
 
 
  if ((aligned_to && tree_int_cst_compare (aligned_to, alignment) < 0)
  if ((aligned_to && tree_int_cst_compare (aligned_to, alignment) < 0)
      || !misalign)
      || !misalign)
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        {
        {
          fprintf (vect_dump, "Unknown alignment for access: ");
          fprintf (vect_dump, "Unknown alignment for access: ");
          print_generic_expr (vect_dump, base, TDF_SLIM);
          print_generic_expr (vect_dump, base, TDF_SLIM);
        }
        }
      return true;
      return true;
    }
    }
 
 
  if ((DECL_P (base)
  if ((DECL_P (base)
       && tree_int_cst_compare (ssize_int (DECL_ALIGN_UNIT (base)),
       && tree_int_cst_compare (ssize_int (DECL_ALIGN_UNIT (base)),
                                alignment) >= 0)
                                alignment) >= 0)
      || (TREE_CODE (base_addr) == SSA_NAME
      || (TREE_CODE (base_addr) == SSA_NAME
          && tree_int_cst_compare (ssize_int (TYPE_ALIGN_UNIT (TREE_TYPE (
          && tree_int_cst_compare (ssize_int (TYPE_ALIGN_UNIT (TREE_TYPE (
                                                      TREE_TYPE (base_addr)))),
                                                      TREE_TYPE (base_addr)))),
                                   alignment) >= 0))
                                   alignment) >= 0))
    base_aligned = true;
    base_aligned = true;
  else
  else
    base_aligned = false;
    base_aligned = false;
 
 
  if (!base_aligned)
  if (!base_aligned)
    {
    {
      /* Do not change the alignment of global variables if
      /* Do not change the alignment of global variables if
         flag_section_anchors is enabled.  */
         flag_section_anchors is enabled.  */
      if (!vect_can_force_dr_alignment_p (base, TYPE_ALIGN (vectype))
      if (!vect_can_force_dr_alignment_p (base, TYPE_ALIGN (vectype))
          || (TREE_STATIC (base) && flag_section_anchors))
          || (TREE_STATIC (base) && flag_section_anchors))
        {
        {
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            {
            {
              fprintf (vect_dump, "can't force alignment of ref: ");
              fprintf (vect_dump, "can't force alignment of ref: ");
              print_generic_expr (vect_dump, ref, TDF_SLIM);
              print_generic_expr (vect_dump, ref, TDF_SLIM);
            }
            }
          return true;
          return true;
        }
        }
 
 
      /* Force the alignment of the decl.
      /* Force the alignment of the decl.
         NOTE: This is the only change to the code we make during
         NOTE: This is the only change to the code we make during
         the analysis phase, before deciding to vectorize the loop.  */
         the analysis phase, before deciding to vectorize the loop.  */
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "force alignment");
        fprintf (vect_dump, "force alignment");
      DECL_ALIGN (base) = TYPE_ALIGN (vectype);
      DECL_ALIGN (base) = TYPE_ALIGN (vectype);
      DECL_USER_ALIGN (base) = 1;
      DECL_USER_ALIGN (base) = 1;
    }
    }
 
 
  /* At this point we assume that the base is aligned.  */
  /* At this point we assume that the base is aligned.  */
  gcc_assert (base_aligned
  gcc_assert (base_aligned
              || (TREE_CODE (base) == VAR_DECL
              || (TREE_CODE (base) == VAR_DECL
                  && DECL_ALIGN (base) >= TYPE_ALIGN (vectype)));
                  && DECL_ALIGN (base) >= TYPE_ALIGN (vectype)));
 
 
  /* Modulo alignment.  */
  /* Modulo alignment.  */
  misalign = size_binop (TRUNC_MOD_EXPR, misalign, alignment);
  misalign = size_binop (TRUNC_MOD_EXPR, misalign, alignment);
 
 
  if (!host_integerp (misalign, 1))
  if (!host_integerp (misalign, 1))
    {
    {
      /* Negative or overflowed misalignment value.  */
      /* Negative or overflowed misalignment value.  */
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "unexpected misalign value");
        fprintf (vect_dump, "unexpected misalign value");
      return false;
      return false;
    }
    }
 
 
  DR_MISALIGNMENT (dr) = TREE_INT_CST_LOW (misalign);
  DR_MISALIGNMENT (dr) = TREE_INT_CST_LOW (misalign);
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    {
    {
      fprintf (vect_dump, "misalign = %d bytes of ref ", DR_MISALIGNMENT (dr));
      fprintf (vect_dump, "misalign = %d bytes of ref ", DR_MISALIGNMENT (dr));
      print_generic_expr (vect_dump, ref, TDF_SLIM);
      print_generic_expr (vect_dump, ref, TDF_SLIM);
    }
    }
 
 
  return true;
  return true;
}
}
 
 
 
 
/* Function vect_compute_data_refs_alignment
/* Function vect_compute_data_refs_alignment
 
 
   Compute the misalignment of data references in the loop.
   Compute the misalignment of data references in the loop.
   Return FALSE if a data reference is found that cannot be vectorized.  */
   Return FALSE if a data reference is found that cannot be vectorized.  */
 
 
static bool
static bool
vect_compute_data_refs_alignment (loop_vec_info loop_vinfo)
vect_compute_data_refs_alignment (loop_vec_info loop_vinfo)
{
{
  VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
  VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
  struct data_reference *dr;
  struct data_reference *dr;
  unsigned int i;
  unsigned int i;
 
 
  for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
  for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
    if (!vect_compute_data_ref_alignment (dr))
    if (!vect_compute_data_ref_alignment (dr))
      return false;
      return false;
 
 
  return true;
  return true;
}
}
 
 
 
 
/* Function vect_update_misalignment_for_peel
/* Function vect_update_misalignment_for_peel
 
 
   DR - the data reference whose misalignment is to be adjusted.
   DR - the data reference whose misalignment is to be adjusted.
   DR_PEEL - the data reference whose misalignment is being made
   DR_PEEL - the data reference whose misalignment is being made
             zero in the vector loop by the peel.
             zero in the vector loop by the peel.
   NPEEL - the number of iterations in the peel loop if the misalignment
   NPEEL - the number of iterations in the peel loop if the misalignment
           of DR_PEEL is known at compile time.  */
           of DR_PEEL is known at compile time.  */
 
 
static void
static void
vect_update_misalignment_for_peel (struct data_reference *dr,
vect_update_misalignment_for_peel (struct data_reference *dr,
                                   struct data_reference *dr_peel, int npeel)
                                   struct data_reference *dr_peel, int npeel)
{
{
  unsigned int i;
  unsigned int i;
  int drsize;
  int drsize;
  VEC(dr_p,heap) *same_align_drs;
  VEC(dr_p,heap) *same_align_drs;
  struct data_reference *current_dr;
  struct data_reference *current_dr;
 
 
  if (known_alignment_for_access_p (dr)
  if (known_alignment_for_access_p (dr)
      && DR_MISALIGNMENT (dr) == DR_MISALIGNMENT (dr_peel))
      && DR_MISALIGNMENT (dr) == DR_MISALIGNMENT (dr_peel))
    {
    {
      DR_MISALIGNMENT (dr) = 0;
      DR_MISALIGNMENT (dr) = 0;
      return;
      return;
    }
    }
 
 
  /* It can be assumed that the data refs with the same alignment as dr_peel
  /* It can be assumed that the data refs with the same alignment as dr_peel
     are aligned in the vector loop.  */
     are aligned in the vector loop.  */
  same_align_drs
  same_align_drs
    = STMT_VINFO_SAME_ALIGN_REFS (vinfo_for_stmt (DR_STMT (dr_peel)));
    = STMT_VINFO_SAME_ALIGN_REFS (vinfo_for_stmt (DR_STMT (dr_peel)));
  for (i = 0; VEC_iterate (dr_p, same_align_drs, i, current_dr); i++)
  for (i = 0; VEC_iterate (dr_p, same_align_drs, i, current_dr); i++)
    {
    {
      if (current_dr != dr)
      if (current_dr != dr)
        continue;
        continue;
      gcc_assert (DR_MISALIGNMENT (dr) == DR_MISALIGNMENT (dr_peel));
      gcc_assert (DR_MISALIGNMENT (dr) == DR_MISALIGNMENT (dr_peel));
      DR_MISALIGNMENT (dr) = 0;
      DR_MISALIGNMENT (dr) = 0;
      return;
      return;
    }
    }
 
 
  if (known_alignment_for_access_p (dr)
  if (known_alignment_for_access_p (dr)
      && known_alignment_for_access_p (dr_peel))
      && known_alignment_for_access_p (dr_peel))
    {
    {
      drsize = GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (DR_REF (dr))));
      drsize = GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (DR_REF (dr))));
      DR_MISALIGNMENT (dr) += npeel * drsize;
      DR_MISALIGNMENT (dr) += npeel * drsize;
      DR_MISALIGNMENT (dr) %= UNITS_PER_SIMD_WORD;
      DR_MISALIGNMENT (dr) %= UNITS_PER_SIMD_WORD;
      return;
      return;
    }
    }
 
 
  DR_MISALIGNMENT (dr) = -1;
  DR_MISALIGNMENT (dr) = -1;
}
}
 
 
 
 
/* Function vect_verify_datarefs_alignment
/* Function vect_verify_datarefs_alignment
 
 
   Return TRUE if all data references in the loop can be
   Return TRUE if all data references in the loop can be
   handled with respect to alignment.  */
   handled with respect to alignment.  */
 
 
static bool
static bool
vect_verify_datarefs_alignment (loop_vec_info loop_vinfo)
vect_verify_datarefs_alignment (loop_vec_info loop_vinfo)
{
{
  VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
  VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
  struct data_reference *dr;
  struct data_reference *dr;
  enum dr_alignment_support supportable_dr_alignment;
  enum dr_alignment_support supportable_dr_alignment;
  unsigned int i;
  unsigned int i;
 
 
  for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
  for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
    {
    {
      supportable_dr_alignment = vect_supportable_dr_alignment (dr);
      supportable_dr_alignment = vect_supportable_dr_alignment (dr);
      if (!supportable_dr_alignment)
      if (!supportable_dr_alignment)
        {
        {
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
            {
            {
              if (DR_IS_READ (dr))
              if (DR_IS_READ (dr))
                fprintf (vect_dump,
                fprintf (vect_dump,
                         "not vectorized: unsupported unaligned load.");
                         "not vectorized: unsupported unaligned load.");
              else
              else
                fprintf (vect_dump,
                fprintf (vect_dump,
                         "not vectorized: unsupported unaligned store.");
                         "not vectorized: unsupported unaligned store.");
            }
            }
          return false;
          return false;
        }
        }
      if (supportable_dr_alignment != dr_aligned
      if (supportable_dr_alignment != dr_aligned
          && vect_print_dump_info (REPORT_ALIGNMENT))
          && vect_print_dump_info (REPORT_ALIGNMENT))
        fprintf (vect_dump, "Vectorizing an unaligned access.");
        fprintf (vect_dump, "Vectorizing an unaligned access.");
    }
    }
  return true;
  return true;
}
}
 
 
 
 
/* Function vector_alignment_reachable_p
/* Function vector_alignment_reachable_p
 
 
   Return true if vector alignment for DR is reachable by peeling
   Return true if vector alignment for DR is reachable by peeling
   a few loop iterations.  Return false otherwise.  */
   a few loop iterations.  Return false otherwise.  */
 
 
static bool
static bool
vector_alignment_reachable_p (struct data_reference *dr)
vector_alignment_reachable_p (struct data_reference *dr)
{
{
  tree stmt = DR_STMT (dr);
  tree stmt = DR_STMT (dr);
  stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
  stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
  tree vectype = STMT_VINFO_VECTYPE (stmt_info);
  tree vectype = STMT_VINFO_VECTYPE (stmt_info);
 
 
  /* If misalignment is known at the compile time then allow peeling
  /* If misalignment is known at the compile time then allow peeling
     only if natural alignment is reachable through peeling.  */
     only if natural alignment is reachable through peeling.  */
  if (known_alignment_for_access_p (dr) && !aligned_access_p (dr))
  if (known_alignment_for_access_p (dr) && !aligned_access_p (dr))
    {
    {
      HOST_WIDE_INT elmsize =
      HOST_WIDE_INT elmsize =
                int_cst_value (TYPE_SIZE_UNIT (TREE_TYPE (vectype)));
                int_cst_value (TYPE_SIZE_UNIT (TREE_TYPE (vectype)));
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        {
        {
          fprintf (vect_dump, "data size =" HOST_WIDE_INT_PRINT_DEC, elmsize);
          fprintf (vect_dump, "data size =" HOST_WIDE_INT_PRINT_DEC, elmsize);
          fprintf (vect_dump, ". misalignment = %d. ", DR_MISALIGNMENT (dr));
          fprintf (vect_dump, ". misalignment = %d. ", DR_MISALIGNMENT (dr));
        }
        }
      if (DR_MISALIGNMENT (dr) % elmsize)
      if (DR_MISALIGNMENT (dr) % elmsize)
        {
        {
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            fprintf (vect_dump, "data size does not divide the misalignment.\n");
            fprintf (vect_dump, "data size does not divide the misalignment.\n");
          return false;
          return false;
        }
        }
    }
    }
 
 
  if (!known_alignment_for_access_p (dr))
  if (!known_alignment_for_access_p (dr))
    {
    {
      tree type = (TREE_TYPE (DR_REF (dr)));
      tree type = (TREE_TYPE (DR_REF (dr)));
      tree ba = DR_BASE_OBJECT (dr);
      tree ba = DR_BASE_OBJECT (dr);
      bool is_packed = false;
      bool is_packed = false;
 
 
      if (ba)
      if (ba)
        is_packed = contains_packed_reference (ba);
        is_packed = contains_packed_reference (ba);
 
 
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "Unknown misalignment, is_packed = %d",is_packed);
        fprintf (vect_dump, "Unknown misalignment, is_packed = %d",is_packed);
      if (targetm.vectorize.vector_alignment_reachable (type, is_packed))
      if (targetm.vectorize.vector_alignment_reachable (type, is_packed))
        return true;
        return true;
      else
      else
        return false;
        return false;
    }
    }
 
 
  return true;
  return true;
}
}
 
 
/* Function vect_enhance_data_refs_alignment
/* Function vect_enhance_data_refs_alignment
 
 
   This pass will use loop versioning and loop peeling in order to enhance
   This pass will use loop versioning and loop peeling in order to enhance
   the alignment of data references in the loop.
   the alignment of data references in the loop.
 
 
   FOR NOW: we assume that whatever versioning/peeling takes place, only the
   FOR NOW: we assume that whatever versioning/peeling takes place, only the
   original loop is to be vectorized; Any other loops that are created by
   original loop is to be vectorized; Any other loops that are created by
   the transformations performed in this pass - are not supposed to be
   the transformations performed in this pass - are not supposed to be
   vectorized. This restriction will be relaxed.
   vectorized. This restriction will be relaxed.
 
 
   This pass will require a cost model to guide it whether to apply peeling
   This pass will require a cost model to guide it whether to apply peeling
   or versioning or a combination of the two. For example, the scheme that
   or versioning or a combination of the two. For example, the scheme that
   intel uses when given a loop with several memory accesses, is as follows:
   intel uses when given a loop with several memory accesses, is as follows:
   choose one memory access ('p') which alignment you want to force by doing
   choose one memory access ('p') which alignment you want to force by doing
   peeling. Then, either (1) generate a loop in which 'p' is aligned and all
   peeling. Then, either (1) generate a loop in which 'p' is aligned and all
   other accesses are not necessarily aligned, or (2) use loop versioning to
   other accesses are not necessarily aligned, or (2) use loop versioning to
   generate one loop in which all accesses are aligned, and another loop in
   generate one loop in which all accesses are aligned, and another loop in
   which only 'p' is necessarily aligned.
   which only 'p' is necessarily aligned.
 
 
   ("Automatic Intra-Register Vectorization for the Intel Architecture",
   ("Automatic Intra-Register Vectorization for the Intel Architecture",
   Aart J.C. Bik, Milind Girkar, Paul M. Grey and Ximmin Tian, International
   Aart J.C. Bik, Milind Girkar, Paul M. Grey and Ximmin Tian, International
   Journal of Parallel Programming, Vol. 30, No. 2, April 2002.)
   Journal of Parallel Programming, Vol. 30, No. 2, April 2002.)
 
 
   Devising a cost model is the most critical aspect of this work. It will
   Devising a cost model is the most critical aspect of this work. It will
   guide us on which access to peel for, whether to use loop versioning, how
   guide us on which access to peel for, whether to use loop versioning, how
   many versions to create, etc. The cost model will probably consist of
   many versions to create, etc. The cost model will probably consist of
   generic considerations as well as target specific considerations (on
   generic considerations as well as target specific considerations (on
   powerpc for example, misaligned stores are more painful than misaligned
   powerpc for example, misaligned stores are more painful than misaligned
   loads).
   loads).
 
 
   Here are the general steps involved in alignment enhancements:
   Here are the general steps involved in alignment enhancements:
 
 
     -- original loop, before alignment analysis:
     -- original loop, before alignment analysis:
        for (i=0; i<N; i++){
        for (i=0; i<N; i++){
          x = q[i];                     # DR_MISALIGNMENT(q) = unknown
          x = q[i];                     # DR_MISALIGNMENT(q) = unknown
          p[i] = y;                     # DR_MISALIGNMENT(p) = unknown
          p[i] = y;                     # DR_MISALIGNMENT(p) = unknown
        }
        }
 
 
     -- After vect_compute_data_refs_alignment:
     -- After vect_compute_data_refs_alignment:
        for (i=0; i<N; i++){
        for (i=0; i<N; i++){
          x = q[i];                     # DR_MISALIGNMENT(q) = 3
          x = q[i];                     # DR_MISALIGNMENT(q) = 3
          p[i] = y;                     # DR_MISALIGNMENT(p) = unknown
          p[i] = y;                     # DR_MISALIGNMENT(p) = unknown
        }
        }
 
 
     -- Possibility 1: we do loop versioning:
     -- Possibility 1: we do loop versioning:
     if (p is aligned) {
     if (p is aligned) {
        for (i=0; i<N; i++){    # loop 1A
        for (i=0; i<N; i++){    # loop 1A
          x = q[i];                     # DR_MISALIGNMENT(q) = 3
          x = q[i];                     # DR_MISALIGNMENT(q) = 3
          p[i] = y;                     # DR_MISALIGNMENT(p) = 0
          p[i] = y;                     # DR_MISALIGNMENT(p) = 0
        }
        }
     }
     }
     else {
     else {
        for (i=0; i<N; i++){    # loop 1B
        for (i=0; i<N; i++){    # loop 1B
          x = q[i];                     # DR_MISALIGNMENT(q) = 3
          x = q[i];                     # DR_MISALIGNMENT(q) = 3
          p[i] = y;                     # DR_MISALIGNMENT(p) = unaligned
          p[i] = y;                     # DR_MISALIGNMENT(p) = unaligned
        }
        }
     }
     }
 
 
     -- Possibility 2: we do loop peeling:
     -- Possibility 2: we do loop peeling:
     for (i = 0; i < 3; i++){   # (scalar loop, not to be vectorized).
     for (i = 0; i < 3; i++){   # (scalar loop, not to be vectorized).
        x = q[i];
        x = q[i];
        p[i] = y;
        p[i] = y;
     }
     }
     for (i = 3; i < N; i++){   # loop 2A
     for (i = 3; i < N; i++){   # loop 2A
        x = q[i];                       # DR_MISALIGNMENT(q) = 0
        x = q[i];                       # DR_MISALIGNMENT(q) = 0
        p[i] = y;                       # DR_MISALIGNMENT(p) = unknown
        p[i] = y;                       # DR_MISALIGNMENT(p) = unknown
     }
     }
 
 
     -- Possibility 3: combination of loop peeling and versioning:
     -- Possibility 3: combination of loop peeling and versioning:
     for (i = 0; i < 3; i++){   # (scalar loop, not to be vectorized).
     for (i = 0; i < 3; i++){   # (scalar loop, not to be vectorized).
        x = q[i];
        x = q[i];
        p[i] = y;
        p[i] = y;
     }
     }
     if (p is aligned) {
     if (p is aligned) {
        for (i = 3; i<N; i++){  # loop 3A
        for (i = 3; i<N; i++){  # loop 3A
          x = q[i];                     # DR_MISALIGNMENT(q) = 0
          x = q[i];                     # DR_MISALIGNMENT(q) = 0
          p[i] = y;                     # DR_MISALIGNMENT(p) = 0
          p[i] = y;                     # DR_MISALIGNMENT(p) = 0
        }
        }
     }
     }
     else {
     else {
        for (i = 3; i<N; i++){  # loop 3B
        for (i = 3; i<N; i++){  # loop 3B
          x = q[i];                     # DR_MISALIGNMENT(q) = 0
          x = q[i];                     # DR_MISALIGNMENT(q) = 0
          p[i] = y;                     # DR_MISALIGNMENT(p) = unaligned
          p[i] = y;                     # DR_MISALIGNMENT(p) = unaligned
        }
        }
     }
     }
 
 
     These loops are later passed to loop_transform to be vectorized. The
     These loops are later passed to loop_transform to be vectorized. The
     vectorizer will use the alignment information to guide the transformation
     vectorizer will use the alignment information to guide the transformation
     (whether to generate regular loads/stores, or with special handling for
     (whether to generate regular loads/stores, or with special handling for
     misalignment).  */
     misalignment).  */
 
 
static bool
static bool
vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
{
{
  VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
  VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
  enum dr_alignment_support supportable_dr_alignment;
  enum dr_alignment_support supportable_dr_alignment;
  struct data_reference *dr0 = NULL;
  struct data_reference *dr0 = NULL;
  struct data_reference *dr;
  struct data_reference *dr;
  unsigned int i;
  unsigned int i;
  bool do_peeling = false;
  bool do_peeling = false;
  bool do_versioning = false;
  bool do_versioning = false;
  bool stat;
  bool stat;
 
 
  /* While cost model enhancements are expected in the future, the high level
  /* While cost model enhancements are expected in the future, the high level
     view of the code at this time is as follows:
     view of the code at this time is as follows:
 
 
     A) If there is a misaligned write then see if peeling to align this write
     A) If there is a misaligned write then see if peeling to align this write
        can make all data references satisfy vect_supportable_dr_alignment.
        can make all data references satisfy vect_supportable_dr_alignment.
        If so, update data structures as needed and return true.  Note that
        If so, update data structures as needed and return true.  Note that
        at this time vect_supportable_dr_alignment is known to return false
        at this time vect_supportable_dr_alignment is known to return false
        for a a misaligned write.
        for a a misaligned write.
 
 
     B) If peeling wasn't possible and there is a data reference with an
     B) If peeling wasn't possible and there is a data reference with an
        unknown misalignment that does not satisfy vect_supportable_dr_alignment
        unknown misalignment that does not satisfy vect_supportable_dr_alignment
        then see if loop versioning checks can be used to make all data
        then see if loop versioning checks can be used to make all data
        references satisfy vect_supportable_dr_alignment.  If so, update
        references satisfy vect_supportable_dr_alignment.  If so, update
        data structures as needed and return true.
        data structures as needed and return true.
 
 
     C) If neither peeling nor versioning were successful then return false if
     C) If neither peeling nor versioning were successful then return false if
        any data reference does not satisfy vect_supportable_dr_alignment.
        any data reference does not satisfy vect_supportable_dr_alignment.
 
 
     D) Return true (all data references satisfy vect_supportable_dr_alignment).
     D) Return true (all data references satisfy vect_supportable_dr_alignment).
 
 
     Note, Possibility 3 above (which is peeling and versioning together) is not
     Note, Possibility 3 above (which is peeling and versioning together) is not
     being done at this time.  */
     being done at this time.  */
 
 
  /* (1) Peeling to force alignment.  */
  /* (1) Peeling to force alignment.  */
 
 
  /* (1.1) Decide whether to perform peeling, and how many iterations to peel:
  /* (1.1) Decide whether to perform peeling, and how many iterations to peel:
     Considerations:
     Considerations:
     + How many accesses will become aligned due to the peeling
     + How many accesses will become aligned due to the peeling
     - How many accesses will become unaligned due to the peeling,
     - How many accesses will become unaligned due to the peeling,
       and the cost of misaligned accesses.
       and the cost of misaligned accesses.
     - The cost of peeling (the extra runtime checks, the increase
     - The cost of peeling (the extra runtime checks, the increase
       in code size).
       in code size).
 
 
     The scheme we use FORNOW: peel to force the alignment of the first
     The scheme we use FORNOW: peel to force the alignment of the first
     misaligned store in the loop.
     misaligned store in the loop.
     Rationale: misaligned stores are not yet supported.
     Rationale: misaligned stores are not yet supported.
 
 
     TODO: Use a cost model.  */
     TODO: Use a cost model.  */
 
 
  for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
  for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
    if (!DR_IS_READ (dr) && !aligned_access_p (dr))
    if (!DR_IS_READ (dr) && !aligned_access_p (dr))
      {
      {
        do_peeling = vector_alignment_reachable_p (dr);
        do_peeling = vector_alignment_reachable_p (dr);
        if (do_peeling)
        if (do_peeling)
          dr0 = dr;
          dr0 = dr;
        if (!do_peeling && vect_print_dump_info (REPORT_DETAILS))
        if (!do_peeling && vect_print_dump_info (REPORT_DETAILS))
          fprintf (vect_dump, "vector alignment may not be reachable");
          fprintf (vect_dump, "vector alignment may not be reachable");
        break;
        break;
      }
      }
 
 
  /* Often peeling for alignment will require peeling for loop-bound, which in
  /* Often peeling for alignment will require peeling for loop-bound, which in
     turn requires that we know how to adjust the loop ivs after the loop.  */
     turn requires that we know how to adjust the loop ivs after the loop.  */
  if (!vect_can_advance_ivs_p (loop_vinfo))
  if (!vect_can_advance_ivs_p (loop_vinfo))
    do_peeling = false;
    do_peeling = false;
 
 
  if (do_peeling)
  if (do_peeling)
    {
    {
      int mis;
      int mis;
      int npeel = 0;
      int npeel = 0;
 
 
      if (known_alignment_for_access_p (dr0))
      if (known_alignment_for_access_p (dr0))
        {
        {
          /* Since it's known at compile time, compute the number of iterations
          /* Since it's known at compile time, compute the number of iterations
             in the peeled loop (the peeling factor) for use in updating
             in the peeled loop (the peeling factor) for use in updating
             DR_MISALIGNMENT values.  The peeling factor is the vectorization
             DR_MISALIGNMENT values.  The peeling factor is the vectorization
             factor minus the misalignment as an element count.  */
             factor minus the misalignment as an element count.  */
          mis = DR_MISALIGNMENT (dr0);
          mis = DR_MISALIGNMENT (dr0);
          mis /= GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (DR_REF (dr0))));
          mis /= GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (DR_REF (dr0))));
          npeel = LOOP_VINFO_VECT_FACTOR (loop_vinfo) - mis;
          npeel = LOOP_VINFO_VECT_FACTOR (loop_vinfo) - mis;
        }
        }
 
 
      /* Ensure that all data refs can be vectorized after the peel.  */
      /* Ensure that all data refs can be vectorized after the peel.  */
      for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
      for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
        {
        {
          int save_misalignment;
          int save_misalignment;
 
 
          if (dr == dr0)
          if (dr == dr0)
            continue;
            continue;
 
 
          save_misalignment = DR_MISALIGNMENT (dr);
          save_misalignment = DR_MISALIGNMENT (dr);
          vect_update_misalignment_for_peel (dr, dr0, npeel);
          vect_update_misalignment_for_peel (dr, dr0, npeel);
          supportable_dr_alignment = vect_supportable_dr_alignment (dr);
          supportable_dr_alignment = vect_supportable_dr_alignment (dr);
          DR_MISALIGNMENT (dr) = save_misalignment;
          DR_MISALIGNMENT (dr) = save_misalignment;
 
 
          if (!supportable_dr_alignment)
          if (!supportable_dr_alignment)
            {
            {
              do_peeling = false;
              do_peeling = false;
              break;
              break;
            }
            }
        }
        }
 
 
      if (do_peeling)
      if (do_peeling)
        {
        {
          /* (1.2) Update the DR_MISALIGNMENT of each data reference DR_i.
          /* (1.2) Update the DR_MISALIGNMENT of each data reference DR_i.
             If the misalignment of DR_i is identical to that of dr0 then set
             If the misalignment of DR_i is identical to that of dr0 then set
             DR_MISALIGNMENT (DR_i) to zero.  If the misalignment of DR_i and
             DR_MISALIGNMENT (DR_i) to zero.  If the misalignment of DR_i and
             dr0 are known at compile time then increment DR_MISALIGNMENT (DR_i)
             dr0 are known at compile time then increment DR_MISALIGNMENT (DR_i)
             by the peeling factor times the element size of DR_i (MOD the
             by the peeling factor times the element size of DR_i (MOD the
             vectorization factor times the size).  Otherwise, the
             vectorization factor times the size).  Otherwise, the
             misalignment of DR_i must be set to unknown.  */
             misalignment of DR_i must be set to unknown.  */
          for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
          for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
            if (dr != dr0)
            if (dr != dr0)
              vect_update_misalignment_for_peel (dr, dr0, npeel);
              vect_update_misalignment_for_peel (dr, dr0, npeel);
 
 
          LOOP_VINFO_UNALIGNED_DR (loop_vinfo) = dr0;
          LOOP_VINFO_UNALIGNED_DR (loop_vinfo) = dr0;
          LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo) = DR_MISALIGNMENT (dr0);
          LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo) = DR_MISALIGNMENT (dr0);
          DR_MISALIGNMENT (dr0) = 0;
          DR_MISALIGNMENT (dr0) = 0;
          if (vect_print_dump_info (REPORT_ALIGNMENT))
          if (vect_print_dump_info (REPORT_ALIGNMENT))
            fprintf (vect_dump, "Alignment of access forced using peeling.");
            fprintf (vect_dump, "Alignment of access forced using peeling.");
 
 
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            fprintf (vect_dump, "Peeling for alignment will be applied.");
            fprintf (vect_dump, "Peeling for alignment will be applied.");
 
 
          stat = vect_verify_datarefs_alignment (loop_vinfo);
          stat = vect_verify_datarefs_alignment (loop_vinfo);
          gcc_assert (stat);
          gcc_assert (stat);
          return stat;
          return stat;
        }
        }
    }
    }
 
 
 
 
  /* (2) Versioning to force alignment.  */
  /* (2) Versioning to force alignment.  */
 
 
  /* Try versioning if:
  /* Try versioning if:
     1) flag_tree_vect_loop_version is TRUE
     1) flag_tree_vect_loop_version is TRUE
     2) optimize_size is FALSE
     2) optimize_size is FALSE
     3) there is at least one unsupported misaligned data ref with an unknown
     3) there is at least one unsupported misaligned data ref with an unknown
        misalignment, and
        misalignment, and
     4) all misaligned data refs with a known misalignment are supported, and
     4) all misaligned data refs with a known misalignment are supported, and
     5) the number of runtime alignment checks is within reason.  */
     5) the number of runtime alignment checks is within reason.  */
 
 
  do_versioning = flag_tree_vect_loop_version && (!optimize_size);
  do_versioning = flag_tree_vect_loop_version && (!optimize_size);
 
 
  if (do_versioning)
  if (do_versioning)
    {
    {
      for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
      for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
        {
        {
          if (aligned_access_p (dr))
          if (aligned_access_p (dr))
            continue;
            continue;
 
 
          supportable_dr_alignment = vect_supportable_dr_alignment (dr);
          supportable_dr_alignment = vect_supportable_dr_alignment (dr);
 
 
          if (!supportable_dr_alignment)
          if (!supportable_dr_alignment)
            {
            {
              tree stmt;
              tree stmt;
              int mask;
              int mask;
              tree vectype;
              tree vectype;
 
 
              if (known_alignment_for_access_p (dr)
              if (known_alignment_for_access_p (dr)
                  || VEC_length (tree,
                  || VEC_length (tree,
                                 LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo))
                                 LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo))
                     >= (unsigned) PARAM_VALUE (PARAM_VECT_MAX_VERSION_CHECKS))
                     >= (unsigned) PARAM_VALUE (PARAM_VECT_MAX_VERSION_CHECKS))
                {
                {
                  do_versioning = false;
                  do_versioning = false;
                  break;
                  break;
                }
                }
 
 
              stmt = DR_STMT (dr);
              stmt = DR_STMT (dr);
              vectype = STMT_VINFO_VECTYPE (vinfo_for_stmt (stmt));
              vectype = STMT_VINFO_VECTYPE (vinfo_for_stmt (stmt));
              gcc_assert (vectype);
              gcc_assert (vectype);
 
 
              /* The rightmost bits of an aligned address must be zeros.
              /* The rightmost bits of an aligned address must be zeros.
                 Construct the mask needed for this test.  For example,
                 Construct the mask needed for this test.  For example,
                 GET_MODE_SIZE for the vector mode V4SI is 16 bytes so the
                 GET_MODE_SIZE for the vector mode V4SI is 16 bytes so the
                 mask must be 15 = 0xf. */
                 mask must be 15 = 0xf. */
              mask = GET_MODE_SIZE (TYPE_MODE (vectype)) - 1;
              mask = GET_MODE_SIZE (TYPE_MODE (vectype)) - 1;
 
 
              /* FORNOW: use the same mask to test all potentially unaligned
              /* FORNOW: use the same mask to test all potentially unaligned
                 references in the loop.  The vectorizer currently supports
                 references in the loop.  The vectorizer currently supports
                 a single vector size, see the reference to
                 a single vector size, see the reference to
                 GET_MODE_NUNITS (TYPE_MODE (vectype)) where the
                 GET_MODE_NUNITS (TYPE_MODE (vectype)) where the
                 vectorization factor is computed.  */
                 vectorization factor is computed.  */
              gcc_assert (!LOOP_VINFO_PTR_MASK (loop_vinfo)
              gcc_assert (!LOOP_VINFO_PTR_MASK (loop_vinfo)
                          || LOOP_VINFO_PTR_MASK (loop_vinfo) == mask);
                          || LOOP_VINFO_PTR_MASK (loop_vinfo) == mask);
              LOOP_VINFO_PTR_MASK (loop_vinfo) = mask;
              LOOP_VINFO_PTR_MASK (loop_vinfo) = mask;
              VEC_safe_push (tree, heap,
              VEC_safe_push (tree, heap,
                             LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo),
                             LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo),
                             DR_STMT (dr));
                             DR_STMT (dr));
            }
            }
        }
        }
 
 
      /* Versioning requires at least one misaligned data reference.  */
      /* Versioning requires at least one misaligned data reference.  */
      if (VEC_length (tree, LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo)) == 0)
      if (VEC_length (tree, LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo)) == 0)
        do_versioning = false;
        do_versioning = false;
      else if (!do_versioning)
      else if (!do_versioning)
        VEC_truncate (tree, LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo), 0);
        VEC_truncate (tree, LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo), 0);
    }
    }
 
 
  if (do_versioning)
  if (do_versioning)
    {
    {
      VEC(tree,heap) *may_misalign_stmts
      VEC(tree,heap) *may_misalign_stmts
        = LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo);
        = LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo);
      tree stmt;
      tree stmt;
 
 
      /* It can now be assumed that the data references in the statements
      /* It can now be assumed that the data references in the statements
         in LOOP_VINFO_MAY_MISALIGN_STMTS will be aligned in the version
         in LOOP_VINFO_MAY_MISALIGN_STMTS will be aligned in the version
         of the loop being vectorized.  */
         of the loop being vectorized.  */
      for (i = 0; VEC_iterate (tree, may_misalign_stmts, i, stmt); i++)
      for (i = 0; VEC_iterate (tree, may_misalign_stmts, i, stmt); i++)
        {
        {
          stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
          stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
          dr = STMT_VINFO_DATA_REF (stmt_info);
          dr = STMT_VINFO_DATA_REF (stmt_info);
          DR_MISALIGNMENT (dr) = 0;
          DR_MISALIGNMENT (dr) = 0;
          if (vect_print_dump_info (REPORT_ALIGNMENT))
          if (vect_print_dump_info (REPORT_ALIGNMENT))
            fprintf (vect_dump, "Alignment of access forced using versioning.");
            fprintf (vect_dump, "Alignment of access forced using versioning.");
        }
        }
 
 
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "Versioning for alignment will be applied.");
        fprintf (vect_dump, "Versioning for alignment will be applied.");
 
 
      /* Peeling and versioning can't be done together at this time.  */
      /* Peeling and versioning can't be done together at this time.  */
      gcc_assert (! (do_peeling && do_versioning));
      gcc_assert (! (do_peeling && do_versioning));
 
 
      stat = vect_verify_datarefs_alignment (loop_vinfo);
      stat = vect_verify_datarefs_alignment (loop_vinfo);
      gcc_assert (stat);
      gcc_assert (stat);
      return stat;
      return stat;
    }
    }
 
 
  /* This point is reached if neither peeling nor versioning is being done.  */
  /* This point is reached if neither peeling nor versioning is being done.  */
  gcc_assert (! (do_peeling || do_versioning));
  gcc_assert (! (do_peeling || do_versioning));
 
 
  stat = vect_verify_datarefs_alignment (loop_vinfo);
  stat = vect_verify_datarefs_alignment (loop_vinfo);
  return stat;
  return stat;
}
}
 
 
 
 
/* Function vect_analyze_data_refs_alignment
/* Function vect_analyze_data_refs_alignment
 
 
   Analyze the alignment of the data-references in the loop.
   Analyze the alignment of the data-references in the loop.
   Return FALSE if a data reference is found that cannot be vectorized.  */
   Return FALSE if a data reference is found that cannot be vectorized.  */
 
 
static bool
static bool
vect_analyze_data_refs_alignment (loop_vec_info loop_vinfo)
vect_analyze_data_refs_alignment (loop_vec_info loop_vinfo)
{
{
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "=== vect_analyze_data_refs_alignment ===");
    fprintf (vect_dump, "=== vect_analyze_data_refs_alignment ===");
 
 
  if (!vect_compute_data_refs_alignment (loop_vinfo))
  if (!vect_compute_data_refs_alignment (loop_vinfo))
    {
    {
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
        fprintf (vect_dump,
        fprintf (vect_dump,
                 "not vectorized: can't calculate alignment for data ref.");
                 "not vectorized: can't calculate alignment for data ref.");
      return false;
      return false;
    }
    }
 
 
  return true;
  return true;
}
}
 
 
 
 
/* Function vect_analyze_data_ref_access.
/* Function vect_analyze_data_ref_access.
 
 
   Analyze the access pattern of the data-reference DR. For now, a data access
   Analyze the access pattern of the data-reference DR. For now, a data access
   has to be consecutive to be considered vectorizable.  */
   has to be consecutive to be considered vectorizable.  */
 
 
static bool
static bool
vect_analyze_data_ref_access (struct data_reference *dr)
vect_analyze_data_ref_access (struct data_reference *dr)
{
{
  tree step = DR_STEP (dr);
  tree step = DR_STEP (dr);
  tree scalar_type = TREE_TYPE (DR_REF (dr));
  tree scalar_type = TREE_TYPE (DR_REF (dr));
 
 
  if (!step || tree_int_cst_compare (step, TYPE_SIZE_UNIT (scalar_type)))
  if (!step || tree_int_cst_compare (step, TYPE_SIZE_UNIT (scalar_type)))
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "not consecutive access");
        fprintf (vect_dump, "not consecutive access");
      return false;
      return false;
    }
    }
  return true;
  return true;
}
}
 
 
 
 
/* Function vect_analyze_data_ref_accesses.
/* Function vect_analyze_data_ref_accesses.
 
 
   Analyze the access pattern of all the data references in the loop.
   Analyze the access pattern of all the data references in the loop.
 
 
   FORNOW: the only access pattern that is considered vectorizable is a
   FORNOW: the only access pattern that is considered vectorizable is a
           simple step 1 (consecutive) access.
           simple step 1 (consecutive) access.
 
 
   FORNOW: handle only arrays and pointer accesses.  */
   FORNOW: handle only arrays and pointer accesses.  */
 
 
static bool
static bool
vect_analyze_data_ref_accesses (loop_vec_info loop_vinfo)
vect_analyze_data_ref_accesses (loop_vec_info loop_vinfo)
{
{
  unsigned int i;
  unsigned int i;
  VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
  VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
  struct data_reference *dr;
  struct data_reference *dr;
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "=== vect_analyze_data_ref_accesses ===");
    fprintf (vect_dump, "=== vect_analyze_data_ref_accesses ===");
 
 
  for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
  for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
    if (!vect_analyze_data_ref_access (dr))
    if (!vect_analyze_data_ref_access (dr))
      {
      {
        if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
        if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
          fprintf (vect_dump, "not vectorized: complicated access pattern.");
          fprintf (vect_dump, "not vectorized: complicated access pattern.");
        return false;
        return false;
      }
      }
 
 
  return true;
  return true;
}
}
 
 
 
 
/* Function vect_analyze_data_refs.
/* Function vect_analyze_data_refs.
 
 
  Find all the data references in the loop.
  Find all the data references in the loop.
 
 
   The general structure of the analysis of data refs in the vectorizer is as
   The general structure of the analysis of data refs in the vectorizer is as
   follows:
   follows:
   1- vect_analyze_data_refs(loop): call compute_data_dependences_for_loop to
   1- vect_analyze_data_refs(loop): call compute_data_dependences_for_loop to
      find and analyze all data-refs in the loop and their dependences.
      find and analyze all data-refs in the loop and their dependences.
   2- vect_analyze_dependences(): apply dependence testing using ddrs.
   2- vect_analyze_dependences(): apply dependence testing using ddrs.
   3- vect_analyze_drs_alignment(): check that ref_stmt.alignment is ok.
   3- vect_analyze_drs_alignment(): check that ref_stmt.alignment is ok.
   4- vect_analyze_drs_access(): check that ref_stmt.step is ok.
   4- vect_analyze_drs_access(): check that ref_stmt.step is ok.
 
 
*/
*/
 
 
static bool
static bool
vect_analyze_data_refs (loop_vec_info loop_vinfo)
vect_analyze_data_refs (loop_vec_info loop_vinfo)
{
{
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  unsigned int i;
  unsigned int i;
  VEC (data_reference_p, heap) *datarefs;
  VEC (data_reference_p, heap) *datarefs;
  struct data_reference *dr;
  struct data_reference *dr;
  tree scalar_type;
  tree scalar_type;
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "=== vect_analyze_data_refs ===");
    fprintf (vect_dump, "=== vect_analyze_data_refs ===");
 
 
  compute_data_dependences_for_loop (loop, false,
  compute_data_dependences_for_loop (loop, false,
                                     &LOOP_VINFO_DATAREFS (loop_vinfo),
                                     &LOOP_VINFO_DATAREFS (loop_vinfo),
                                     &LOOP_VINFO_DDRS (loop_vinfo));
                                     &LOOP_VINFO_DDRS (loop_vinfo));
 
 
  /* Go through the data-refs, check that the analysis succeeded. Update pointer
  /* Go through the data-refs, check that the analysis succeeded. Update pointer
     from stmt_vec_info struct to DR and vectype.  */
     from stmt_vec_info struct to DR and vectype.  */
  datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
  datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
 
 
  for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
  for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
    {
    {
      tree stmt;
      tree stmt;
      stmt_vec_info stmt_info;
      stmt_vec_info stmt_info;
 
 
      if (!dr || !DR_REF (dr))
      if (!dr || !DR_REF (dr))
        {
        {
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
            fprintf (vect_dump, "not vectorized: unhandled data-ref ");
            fprintf (vect_dump, "not vectorized: unhandled data-ref ");
          return false;
          return false;
        }
        }
 
 
      /* Update DR field in stmt_vec_info struct.  */
      /* Update DR field in stmt_vec_info struct.  */
      stmt = DR_STMT (dr);
      stmt = DR_STMT (dr);
      stmt_info = vinfo_for_stmt (stmt);
      stmt_info = vinfo_for_stmt (stmt);
 
 
      if (STMT_VINFO_DATA_REF (stmt_info))
      if (STMT_VINFO_DATA_REF (stmt_info))
        {
        {
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
            {
            {
              fprintf (vect_dump,
              fprintf (vect_dump,
                       "not vectorized: more than one data ref in stmt: ");
                       "not vectorized: more than one data ref in stmt: ");
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
            }
            }
          return false;
          return false;
        }
        }
      STMT_VINFO_DATA_REF (stmt_info) = dr;
      STMT_VINFO_DATA_REF (stmt_info) = dr;
 
 
      /* Check that analysis of the data-ref succeeded.  */
      /* Check that analysis of the data-ref succeeded.  */
      if (!DR_BASE_ADDRESS (dr) || !DR_OFFSET (dr) || !DR_INIT (dr)
      if (!DR_BASE_ADDRESS (dr) || !DR_OFFSET (dr) || !DR_INIT (dr)
          || !DR_STEP (dr))
          || !DR_STEP (dr))
        {
        {
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
            {
            {
              fprintf (vect_dump, "not vectorized: data ref analysis failed ");
              fprintf (vect_dump, "not vectorized: data ref analysis failed ");
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
            }
            }
          return false;
          return false;
        }
        }
      if (!DR_MEMTAG (dr))
      if (!DR_MEMTAG (dr))
        {
        {
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
            {
            {
              fprintf (vect_dump, "not vectorized: no memory tag for ");
              fprintf (vect_dump, "not vectorized: no memory tag for ");
              print_generic_expr (vect_dump, DR_REF (dr), TDF_SLIM);
              print_generic_expr (vect_dump, DR_REF (dr), TDF_SLIM);
            }
            }
          return false;
          return false;
        }
        }
 
 
      /* Set vectype for STMT.  */
      /* Set vectype for STMT.  */
      scalar_type = TREE_TYPE (DR_REF (dr));
      scalar_type = TREE_TYPE (DR_REF (dr));
      STMT_VINFO_VECTYPE (stmt_info) =
      STMT_VINFO_VECTYPE (stmt_info) =
                get_vectype_for_scalar_type (scalar_type);
                get_vectype_for_scalar_type (scalar_type);
      if (!STMT_VINFO_VECTYPE (stmt_info))
      if (!STMT_VINFO_VECTYPE (stmt_info))
        {
        {
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
            {
            {
              fprintf (vect_dump,
              fprintf (vect_dump,
                       "not vectorized: no vectype for stmt: ");
                       "not vectorized: no vectype for stmt: ");
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
              fprintf (vect_dump, " scalar_type: ");
              fprintf (vect_dump, " scalar_type: ");
              print_generic_expr (vect_dump, scalar_type, TDF_DETAILS);
              print_generic_expr (vect_dump, scalar_type, TDF_DETAILS);
            }
            }
          return false;
          return false;
        }
        }
    }
    }
 
 
  return true;
  return true;
}
}
 
 
 
 
/* Utility functions used by vect_mark_stmts_to_be_vectorized.  */
/* Utility functions used by vect_mark_stmts_to_be_vectorized.  */
 
 
/* Function vect_mark_relevant.
/* Function vect_mark_relevant.
 
 
   Mark STMT as "relevant for vectorization" and add it to WORKLIST.  */
   Mark STMT as "relevant for vectorization" and add it to WORKLIST.  */
 
 
static void
static void
vect_mark_relevant (VEC(tree,heap) **worklist, tree stmt,
vect_mark_relevant (VEC(tree,heap) **worklist, tree stmt,
                    bool relevant_p, bool live_p)
                    bool relevant_p, bool live_p)
{
{
  stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
  stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
  bool save_relevant_p = STMT_VINFO_RELEVANT_P (stmt_info);
  bool save_relevant_p = STMT_VINFO_RELEVANT_P (stmt_info);
  bool save_live_p = STMT_VINFO_LIVE_P (stmt_info);
  bool save_live_p = STMT_VINFO_LIVE_P (stmt_info);
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "mark relevant %d, live %d.",relevant_p, live_p);
    fprintf (vect_dump, "mark relevant %d, live %d.",relevant_p, live_p);
 
 
  if (STMT_VINFO_IN_PATTERN_P (stmt_info))
  if (STMT_VINFO_IN_PATTERN_P (stmt_info))
    {
    {
      tree pattern_stmt;
      tree pattern_stmt;
 
 
      /* This is the last stmt in a sequence that was detected as a
      /* This is the last stmt in a sequence that was detected as a
         pattern that can potentially be vectorized.  Don't mark the stmt
         pattern that can potentially be vectorized.  Don't mark the stmt
         as relevant/live because it's not going to vectorized.
         as relevant/live because it's not going to vectorized.
         Instead mark the pattern-stmt that replaces it.  */
         Instead mark the pattern-stmt that replaces it.  */
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "last stmt in pattern. don't mark relevant/live.");
        fprintf (vect_dump, "last stmt in pattern. don't mark relevant/live.");
      pattern_stmt = STMT_VINFO_RELATED_STMT (stmt_info);
      pattern_stmt = STMT_VINFO_RELATED_STMT (stmt_info);
      stmt_info = vinfo_for_stmt (pattern_stmt);
      stmt_info = vinfo_for_stmt (pattern_stmt);
      gcc_assert (STMT_VINFO_RELATED_STMT (stmt_info) == stmt);
      gcc_assert (STMT_VINFO_RELATED_STMT (stmt_info) == stmt);
      save_relevant_p = STMT_VINFO_RELEVANT_P (stmt_info);
      save_relevant_p = STMT_VINFO_RELEVANT_P (stmt_info);
      save_live_p = STMT_VINFO_LIVE_P (stmt_info);
      save_live_p = STMT_VINFO_LIVE_P (stmt_info);
      stmt = pattern_stmt;
      stmt = pattern_stmt;
    }
    }
 
 
  STMT_VINFO_LIVE_P (stmt_info) |= live_p;
  STMT_VINFO_LIVE_P (stmt_info) |= live_p;
  STMT_VINFO_RELEVANT_P (stmt_info) |= relevant_p;
  STMT_VINFO_RELEVANT_P (stmt_info) |= relevant_p;
 
 
  if (TREE_CODE (stmt) == PHI_NODE)
  if (TREE_CODE (stmt) == PHI_NODE)
    /* Don't put phi-nodes in the worklist. Phis that are marked relevant
    /* Don't put phi-nodes in the worklist. Phis that are marked relevant
       or live will fail vectorization later on.  */
       or live will fail vectorization later on.  */
    return;
    return;
 
 
  if (STMT_VINFO_RELEVANT_P (stmt_info) == save_relevant_p
  if (STMT_VINFO_RELEVANT_P (stmt_info) == save_relevant_p
      && STMT_VINFO_LIVE_P (stmt_info) == save_live_p)
      && STMT_VINFO_LIVE_P (stmt_info) == save_live_p)
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "already marked relevant/live.");
        fprintf (vect_dump, "already marked relevant/live.");
      return;
      return;
    }
    }
 
 
  VEC_safe_push (tree, heap, *worklist, stmt);
  VEC_safe_push (tree, heap, *worklist, stmt);
}
}
 
 
 
 
/* Function vect_stmt_relevant_p.
/* Function vect_stmt_relevant_p.
 
 
   Return true if STMT in loop that is represented by LOOP_VINFO is
   Return true if STMT in loop that is represented by LOOP_VINFO is
   "relevant for vectorization".
   "relevant for vectorization".
 
 
   A stmt is considered "relevant for vectorization" if:
   A stmt is considered "relevant for vectorization" if:
   - it has uses outside the loop.
   - it has uses outside the loop.
   - it has vdefs (it alters memory).
   - it has vdefs (it alters memory).
   - control stmts in the loop (except for the exit condition).
   - control stmts in the loop (except for the exit condition).
 
 
   CHECKME: what other side effects would the vectorizer allow?  */
   CHECKME: what other side effects would the vectorizer allow?  */
 
 
static bool
static bool
vect_stmt_relevant_p (tree stmt, loop_vec_info loop_vinfo,
vect_stmt_relevant_p (tree stmt, loop_vec_info loop_vinfo,
                      bool *relevant_p, bool *live_p)
                      bool *relevant_p, bool *live_p)
{
{
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  ssa_op_iter op_iter;
  ssa_op_iter op_iter;
  imm_use_iterator imm_iter;
  imm_use_iterator imm_iter;
  use_operand_p use_p;
  use_operand_p use_p;
  def_operand_p def_p;
  def_operand_p def_p;
 
 
  *relevant_p = false;
  *relevant_p = false;
  *live_p = false;
  *live_p = false;
 
 
  /* cond stmt other than loop exit cond.  */
  /* cond stmt other than loop exit cond.  */
  if (is_ctrl_stmt (stmt) && (stmt != LOOP_VINFO_EXIT_COND (loop_vinfo)))
  if (is_ctrl_stmt (stmt) && (stmt != LOOP_VINFO_EXIT_COND (loop_vinfo)))
    *relevant_p = true;
    *relevant_p = true;
 
 
  /* changing memory.  */
  /* changing memory.  */
  if (TREE_CODE (stmt) != PHI_NODE)
  if (TREE_CODE (stmt) != PHI_NODE)
    if (!ZERO_SSA_OPERANDS (stmt, SSA_OP_VIRTUAL_DEFS))
    if (!ZERO_SSA_OPERANDS (stmt, SSA_OP_VIRTUAL_DEFS))
      {
      {
        if (vect_print_dump_info (REPORT_DETAILS))
        if (vect_print_dump_info (REPORT_DETAILS))
          fprintf (vect_dump, "vec_stmt_relevant_p: stmt has vdefs.");
          fprintf (vect_dump, "vec_stmt_relevant_p: stmt has vdefs.");
        *relevant_p = true;
        *relevant_p = true;
      }
      }
 
 
  /* uses outside the loop.  */
  /* uses outside the loop.  */
  FOR_EACH_PHI_OR_STMT_DEF (def_p, stmt, op_iter, SSA_OP_DEF)
  FOR_EACH_PHI_OR_STMT_DEF (def_p, stmt, op_iter, SSA_OP_DEF)
    {
    {
      FOR_EACH_IMM_USE_FAST (use_p, imm_iter, DEF_FROM_PTR (def_p))
      FOR_EACH_IMM_USE_FAST (use_p, imm_iter, DEF_FROM_PTR (def_p))
        {
        {
          basic_block bb = bb_for_stmt (USE_STMT (use_p));
          basic_block bb = bb_for_stmt (USE_STMT (use_p));
          if (!flow_bb_inside_loop_p (loop, bb))
          if (!flow_bb_inside_loop_p (loop, bb))
            {
            {
              if (vect_print_dump_info (REPORT_DETAILS))
              if (vect_print_dump_info (REPORT_DETAILS))
                fprintf (vect_dump, "vec_stmt_relevant_p: used out of loop.");
                fprintf (vect_dump, "vec_stmt_relevant_p: used out of loop.");
 
 
              /* We expect all such uses to be in the loop exit phis
              /* We expect all such uses to be in the loop exit phis
                 (because of loop closed form)   */
                 (because of loop closed form)   */
              gcc_assert (TREE_CODE (USE_STMT (use_p)) == PHI_NODE);
              gcc_assert (TREE_CODE (USE_STMT (use_p)) == PHI_NODE);
              gcc_assert (bb == loop->single_exit->dest);
              gcc_assert (bb == loop->single_exit->dest);
 
 
              *live_p = true;
              *live_p = true;
            }
            }
        }
        }
    }
    }
 
 
  return (*live_p || *relevant_p);
  return (*live_p || *relevant_p);
}
}
 
 
 
 
/* Function vect_mark_stmts_to_be_vectorized.
/* Function vect_mark_stmts_to_be_vectorized.
 
 
   Not all stmts in the loop need to be vectorized. For example:
   Not all stmts in the loop need to be vectorized. For example:
 
 
     for i...
     for i...
       for j...
       for j...
   1.    T0 = i + j
   1.    T0 = i + j
   2.    T1 = a[T0]
   2.    T1 = a[T0]
 
 
   3.    j = j + 1
   3.    j = j + 1
 
 
   Stmt 1 and 3 do not need to be vectorized, because loop control and
   Stmt 1 and 3 do not need to be vectorized, because loop control and
   addressing of vectorized data-refs are handled differently.
   addressing of vectorized data-refs are handled differently.
 
 
   This pass detects such stmts.  */
   This pass detects such stmts.  */
 
 
static bool
static bool
vect_mark_stmts_to_be_vectorized (loop_vec_info loop_vinfo)
vect_mark_stmts_to_be_vectorized (loop_vec_info loop_vinfo)
{
{
  VEC(tree,heap) *worklist;
  VEC(tree,heap) *worklist;
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
  basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
  unsigned int nbbs = loop->num_nodes;
  unsigned int nbbs = loop->num_nodes;
  block_stmt_iterator si;
  block_stmt_iterator si;
  tree stmt, use;
  tree stmt, use;
  stmt_ann_t ann;
  stmt_ann_t ann;
  ssa_op_iter iter;
  ssa_op_iter iter;
  unsigned int i;
  unsigned int i;
  stmt_vec_info stmt_vinfo;
  stmt_vec_info stmt_vinfo;
  basic_block bb;
  basic_block bb;
  tree phi;
  tree phi;
  bool relevant_p, live_p;
  bool relevant_p, live_p;
  tree def, def_stmt;
  tree def, def_stmt;
  enum vect_def_type dt;
  enum vect_def_type dt;
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "=== vect_mark_stmts_to_be_vectorized ===");
    fprintf (vect_dump, "=== vect_mark_stmts_to_be_vectorized ===");
 
 
  worklist = VEC_alloc (tree, heap, 64);
  worklist = VEC_alloc (tree, heap, 64);
 
 
  /* 1. Init worklist.  */
  /* 1. Init worklist.  */
 
 
  bb = loop->header;
  bb = loop->header;
  for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
  for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        {
        {
          fprintf (vect_dump, "init: phi relevant? ");
          fprintf (vect_dump, "init: phi relevant? ");
          print_generic_expr (vect_dump, phi, TDF_SLIM);
          print_generic_expr (vect_dump, phi, TDF_SLIM);
        }
        }
 
 
      if (vect_stmt_relevant_p (phi, loop_vinfo, &relevant_p, &live_p))
      if (vect_stmt_relevant_p (phi, loop_vinfo, &relevant_p, &live_p))
        vect_mark_relevant (&worklist, phi, relevant_p, live_p);
        vect_mark_relevant (&worklist, phi, relevant_p, live_p);
    }
    }
 
 
  for (i = 0; i < nbbs; i++)
  for (i = 0; i < nbbs; i++)
    {
    {
      bb = bbs[i];
      bb = bbs[i];
      for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
      for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
        {
        {
          stmt = bsi_stmt (si);
          stmt = bsi_stmt (si);
 
 
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            {
            {
              fprintf (vect_dump, "init: stmt relevant? ");
              fprintf (vect_dump, "init: stmt relevant? ");
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
            }
            }
 
 
          if (vect_stmt_relevant_p (stmt, loop_vinfo, &relevant_p, &live_p))
          if (vect_stmt_relevant_p (stmt, loop_vinfo, &relevant_p, &live_p))
            vect_mark_relevant (&worklist, stmt, relevant_p, live_p);
            vect_mark_relevant (&worklist, stmt, relevant_p, live_p);
        }
        }
    }
    }
 
 
 
 
  /* 2. Process_worklist */
  /* 2. Process_worklist */
 
 
  while (VEC_length (tree, worklist) > 0)
  while (VEC_length (tree, worklist) > 0)
    {
    {
      stmt = VEC_pop (tree, worklist);
      stmt = VEC_pop (tree, worklist);
 
 
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        {
        {
          fprintf (vect_dump, "worklist: examine stmt: ");
          fprintf (vect_dump, "worklist: examine stmt: ");
          print_generic_expr (vect_dump, stmt, TDF_SLIM);
          print_generic_expr (vect_dump, stmt, TDF_SLIM);
        }
        }
 
 
      /* Examine the USEs of STMT. For each ssa-name USE thta is defined
      /* Examine the USEs of STMT. For each ssa-name USE thta is defined
         in the loop, mark the stmt that defines it (DEF_STMT) as
         in the loop, mark the stmt that defines it (DEF_STMT) as
         relevant/irrelevant and live/dead according to the liveness and
         relevant/irrelevant and live/dead according to the liveness and
         relevance properties of STMT.
         relevance properties of STMT.
       */
       */
 
 
      gcc_assert (TREE_CODE (stmt) != PHI_NODE);
      gcc_assert (TREE_CODE (stmt) != PHI_NODE);
 
 
      ann = stmt_ann (stmt);
      ann = stmt_ann (stmt);
      stmt_vinfo = vinfo_for_stmt (stmt);
      stmt_vinfo = vinfo_for_stmt (stmt);
 
 
      relevant_p = STMT_VINFO_RELEVANT_P (stmt_vinfo);
      relevant_p = STMT_VINFO_RELEVANT_P (stmt_vinfo);
      live_p = STMT_VINFO_LIVE_P (stmt_vinfo);
      live_p = STMT_VINFO_LIVE_P (stmt_vinfo);
 
 
      /* Generally, the liveness and relevance properties of STMT are
      /* Generally, the liveness and relevance properties of STMT are
         propagated to the DEF_STMTs of its USEs:
         propagated to the DEF_STMTs of its USEs:
             STMT_VINFO_LIVE_P (DEF_STMT_info) <-- live_p
             STMT_VINFO_LIVE_P (DEF_STMT_info) <-- live_p
             STMT_VINFO_RELEVANT_P (DEF_STMT_info) <-- relevant_p
             STMT_VINFO_RELEVANT_P (DEF_STMT_info) <-- relevant_p
 
 
         Exceptions:
         Exceptions:
 
 
         (case 1)
         (case 1)
           If USE is used only for address computations (e.g. array indexing),
           If USE is used only for address computations (e.g. array indexing),
           which does not need to be directly vectorized, then the
           which does not need to be directly vectorized, then the
           liveness/relevance of the respective DEF_STMT is left unchanged.
           liveness/relevance of the respective DEF_STMT is left unchanged.
 
 
         (case 2)
         (case 2)
           If STMT has been identified as defining a reduction variable, then
           If STMT has been identified as defining a reduction variable, then
           we have two cases:
           we have two cases:
           (case 2.1)
           (case 2.1)
             The last use of STMT is the reduction-variable, which is defined
             The last use of STMT is the reduction-variable, which is defined
             by a loop-header-phi. We don't want to mark the phi as live or
             by a loop-header-phi. We don't want to mark the phi as live or
             relevant (because it does not need to be vectorized, it is handled
             relevant (because it does not need to be vectorized, it is handled
             as part of the vectorization of the reduction), so in this case we
             as part of the vectorization of the reduction), so in this case we
             skip the call to vect_mark_relevant.
             skip the call to vect_mark_relevant.
           (case 2.2)
           (case 2.2)
             The rest of the uses of STMT are defined in the loop body. For
             The rest of the uses of STMT are defined in the loop body. For
             the def_stmt of these uses we want to set liveness/relevance
             the def_stmt of these uses we want to set liveness/relevance
             as follows:
             as follows:
               STMT_VINFO_LIVE_P (DEF_STMT_info) <-- false
               STMT_VINFO_LIVE_P (DEF_STMT_info) <-- false
               STMT_VINFO_RELEVANT_P (DEF_STMT_info) <-- true
               STMT_VINFO_RELEVANT_P (DEF_STMT_info) <-- true
             because even though STMT is classified as live (since it defines a
             because even though STMT is classified as live (since it defines a
             value that is used across loop iterations) and irrelevant (since it
             value that is used across loop iterations) and irrelevant (since it
             is not used inside the loop), it will be vectorized, and therefore
             is not used inside the loop), it will be vectorized, and therefore
             the corresponding DEF_STMTs need to marked as relevant.
             the corresponding DEF_STMTs need to marked as relevant.
       */
       */
 
 
      /* case 2.2:  */
      /* case 2.2:  */
      if (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_reduction_def)
      if (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_reduction_def)
        {
        {
          gcc_assert (!relevant_p && live_p);
          gcc_assert (!relevant_p && live_p);
          relevant_p = true;
          relevant_p = true;
          live_p = false;
          live_p = false;
        }
        }
 
 
      FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE)
      FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE)
        {
        {
          /* case 1: we are only interested in uses that need to be vectorized.
          /* case 1: we are only interested in uses that need to be vectorized.
             Uses that are used for address computation are not considered
             Uses that are used for address computation are not considered
             relevant.
             relevant.
           */
           */
          if (!exist_non_indexing_operands_for_use_p (use, stmt))
          if (!exist_non_indexing_operands_for_use_p (use, stmt))
            continue;
            continue;
 
 
          if (!vect_is_simple_use (use, loop_vinfo, &def_stmt, &def, &dt))
          if (!vect_is_simple_use (use, loop_vinfo, &def_stmt, &def, &dt))
            {
            {
              if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
              if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                fprintf (vect_dump, "not vectorized: unsupported use in stmt.");
                fprintf (vect_dump, "not vectorized: unsupported use in stmt.");
              VEC_free (tree, heap, worklist);
              VEC_free (tree, heap, worklist);
              return false;
              return false;
            }
            }
 
 
          if (!def_stmt || IS_EMPTY_STMT (def_stmt))
          if (!def_stmt || IS_EMPTY_STMT (def_stmt))
            continue;
            continue;
 
 
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            {
            {
              fprintf (vect_dump, "worklist: examine use %d: ", i);
              fprintf (vect_dump, "worklist: examine use %d: ", i);
              print_generic_expr (vect_dump, use, TDF_SLIM);
              print_generic_expr (vect_dump, use, TDF_SLIM);
            }
            }
 
 
          bb = bb_for_stmt (def_stmt);
          bb = bb_for_stmt (def_stmt);
          if (!flow_bb_inside_loop_p (loop, bb))
          if (!flow_bb_inside_loop_p (loop, bb))
            continue;
            continue;
 
 
          /* case 2.1: the reduction-use does not mark the defining-phi
          /* case 2.1: the reduction-use does not mark the defining-phi
             as relevant.  */
             as relevant.  */
          if (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_reduction_def
          if (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_reduction_def
              && TREE_CODE (def_stmt) == PHI_NODE)
              && TREE_CODE (def_stmt) == PHI_NODE)
            continue;
            continue;
 
 
          vect_mark_relevant (&worklist, def_stmt, relevant_p, live_p);
          vect_mark_relevant (&worklist, def_stmt, relevant_p, live_p);
        }
        }
    }                           /* while worklist */
    }                           /* while worklist */
 
 
  VEC_free (tree, heap, worklist);
  VEC_free (tree, heap, worklist);
  return true;
  return true;
}
}
 
 
 
 
/* Function vect_can_advance_ivs_p
/* Function vect_can_advance_ivs_p
 
 
   In case the number of iterations that LOOP iterates is unknown at compile
   In case the number of iterations that LOOP iterates is unknown at compile
   time, an epilog loop will be generated, and the loop induction variables
   time, an epilog loop will be generated, and the loop induction variables
   (IVs) will be "advanced" to the value they are supposed to take just before
   (IVs) will be "advanced" to the value they are supposed to take just before
   the epilog loop.  Here we check that the access function of the loop IVs
   the epilog loop.  Here we check that the access function of the loop IVs
   and the expression that represents the loop bound are simple enough.
   and the expression that represents the loop bound are simple enough.
   These restrictions will be relaxed in the future.  */
   These restrictions will be relaxed in the future.  */
 
 
static bool
static bool
vect_can_advance_ivs_p (loop_vec_info loop_vinfo)
vect_can_advance_ivs_p (loop_vec_info loop_vinfo)
{
{
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
  basic_block bb = loop->header;
  basic_block bb = loop->header;
  tree phi;
  tree phi;
 
 
  /* Analyze phi functions of the loop header.  */
  /* Analyze phi functions of the loop header.  */
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "=== vect_can_advance_ivs_p ===");
    fprintf (vect_dump, "=== vect_can_advance_ivs_p ===");
 
 
  for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
  for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
    {
    {
      tree access_fn = NULL;
      tree access_fn = NULL;
      tree evolution_part;
      tree evolution_part;
 
 
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        {
        {
          fprintf (vect_dump, "Analyze phi: ");
          fprintf (vect_dump, "Analyze phi: ");
          print_generic_expr (vect_dump, phi, TDF_SLIM);
          print_generic_expr (vect_dump, phi, TDF_SLIM);
        }
        }
 
 
      /* Skip virtual phi's. The data dependences that are associated with
      /* Skip virtual phi's. The data dependences that are associated with
         virtual defs/uses (i.e., memory accesses) are analyzed elsewhere.  */
         virtual defs/uses (i.e., memory accesses) are analyzed elsewhere.  */
 
 
      if (!is_gimple_reg (SSA_NAME_VAR (PHI_RESULT (phi))))
      if (!is_gimple_reg (SSA_NAME_VAR (PHI_RESULT (phi))))
        {
        {
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            fprintf (vect_dump, "virtual phi. skip.");
            fprintf (vect_dump, "virtual phi. skip.");
          continue;
          continue;
        }
        }
 
 
      /* Skip reduction phis.  */
      /* Skip reduction phis.  */
 
 
      if (STMT_VINFO_DEF_TYPE (vinfo_for_stmt (phi)) == vect_reduction_def)
      if (STMT_VINFO_DEF_TYPE (vinfo_for_stmt (phi)) == vect_reduction_def)
        {
        {
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            fprintf (vect_dump, "reduc phi. skip.");
            fprintf (vect_dump, "reduc phi. skip.");
          continue;
          continue;
        }
        }
 
 
      /* Analyze the evolution function.  */
      /* Analyze the evolution function.  */
 
 
      access_fn = instantiate_parameters
      access_fn = instantiate_parameters
        (loop, analyze_scalar_evolution (loop, PHI_RESULT (phi)));
        (loop, analyze_scalar_evolution (loop, PHI_RESULT (phi)));
 
 
      if (!access_fn)
      if (!access_fn)
        {
        {
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            fprintf (vect_dump, "No Access function.");
            fprintf (vect_dump, "No Access function.");
          return false;
          return false;
        }
        }
 
 
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        {
        {
          fprintf (vect_dump, "Access function of PHI: ");
          fprintf (vect_dump, "Access function of PHI: ");
          print_generic_expr (vect_dump, access_fn, TDF_SLIM);
          print_generic_expr (vect_dump, access_fn, TDF_SLIM);
        }
        }
 
 
      evolution_part = evolution_part_in_loop_num (access_fn, loop->num);
      evolution_part = evolution_part_in_loop_num (access_fn, loop->num);
 
 
      if (evolution_part == NULL_TREE)
      if (evolution_part == NULL_TREE)
        {
        {
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            fprintf (vect_dump, "No evolution.");
            fprintf (vect_dump, "No evolution.");
          return false;
          return false;
        }
        }
 
 
      /* FORNOW: We do not transform initial conditions of IVs
      /* FORNOW: We do not transform initial conditions of IVs
         which evolution functions are a polynomial of degree >= 2.  */
         which evolution functions are a polynomial of degree >= 2.  */
 
 
      if (tree_is_chrec (evolution_part))
      if (tree_is_chrec (evolution_part))
        return false;
        return false;
    }
    }
 
 
  return true;
  return true;
}
}
 
 
 
 
/* Function vect_get_loop_niters.
/* Function vect_get_loop_niters.
 
 
   Determine how many iterations the loop is executed.
   Determine how many iterations the loop is executed.
   If an expression that represents the number of iterations
   If an expression that represents the number of iterations
   can be constructed, place it in NUMBER_OF_ITERATIONS.
   can be constructed, place it in NUMBER_OF_ITERATIONS.
   Return the loop exit condition.  */
   Return the loop exit condition.  */
 
 
static tree
static tree
vect_get_loop_niters (struct loop *loop, tree *number_of_iterations)
vect_get_loop_niters (struct loop *loop, tree *number_of_iterations)
{
{
  tree niters;
  tree niters;
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "=== get_loop_niters ===");
    fprintf (vect_dump, "=== get_loop_niters ===");
 
 
  niters = number_of_iterations_in_loop (loop);
  niters = number_of_iterations_in_loop (loop);
 
 
  if (niters != NULL_TREE
  if (niters != NULL_TREE
      && niters != chrec_dont_know)
      && niters != chrec_dont_know)
    {
    {
      *number_of_iterations = niters;
      *number_of_iterations = niters;
 
 
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        {
        {
          fprintf (vect_dump, "==> get_loop_niters:" );
          fprintf (vect_dump, "==> get_loop_niters:" );
          print_generic_expr (vect_dump, *number_of_iterations, TDF_SLIM);
          print_generic_expr (vect_dump, *number_of_iterations, TDF_SLIM);
        }
        }
    }
    }
 
 
  return get_loop_exit_condition (loop);
  return get_loop_exit_condition (loop);
}
}
 
 
 
 
/* Function vect_analyze_loop_form.
/* Function vect_analyze_loop_form.
 
 
   Verify the following restrictions (some may be relaxed in the future):
   Verify the following restrictions (some may be relaxed in the future):
   - it's an inner-most loop
   - it's an inner-most loop
   - number of BBs = 2 (which are the loop header and the latch)
   - number of BBs = 2 (which are the loop header and the latch)
   - the loop has a pre-header
   - the loop has a pre-header
   - the loop has a single entry and exit
   - the loop has a single entry and exit
   - the loop exit condition is simple enough, and the number of iterations
   - the loop exit condition is simple enough, and the number of iterations
     can be analyzed (a countable loop).  */
     can be analyzed (a countable loop).  */
 
 
static loop_vec_info
static loop_vec_info
vect_analyze_loop_form (struct loop *loop)
vect_analyze_loop_form (struct loop *loop)
{
{
  loop_vec_info loop_vinfo;
  loop_vec_info loop_vinfo;
  tree loop_cond;
  tree loop_cond;
  tree number_of_iterations = NULL;
  tree number_of_iterations = NULL;
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "=== vect_analyze_loop_form ===");
    fprintf (vect_dump, "=== vect_analyze_loop_form ===");
 
 
  if (loop->inner)
  if (loop->inner)
    {
    {
      if (vect_print_dump_info (REPORT_OUTER_LOOPS))
      if (vect_print_dump_info (REPORT_OUTER_LOOPS))
        fprintf (vect_dump, "not vectorized: nested loop.");
        fprintf (vect_dump, "not vectorized: nested loop.");
      return NULL;
      return NULL;
    }
    }
 
 
  if (!loop->single_exit
  if (!loop->single_exit
      || loop->num_nodes != 2
      || loop->num_nodes != 2
      || EDGE_COUNT (loop->header->preds) != 2)
      || EDGE_COUNT (loop->header->preds) != 2)
    {
    {
      if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
      if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
        {
        {
          if (!loop->single_exit)
          if (!loop->single_exit)
            fprintf (vect_dump, "not vectorized: multiple exits.");
            fprintf (vect_dump, "not vectorized: multiple exits.");
          else if (loop->num_nodes != 2)
          else if (loop->num_nodes != 2)
            fprintf (vect_dump, "not vectorized: too many BBs in loop.");
            fprintf (vect_dump, "not vectorized: too many BBs in loop.");
          else if (EDGE_COUNT (loop->header->preds) != 2)
          else if (EDGE_COUNT (loop->header->preds) != 2)
            fprintf (vect_dump, "not vectorized: too many incoming edges.");
            fprintf (vect_dump, "not vectorized: too many incoming edges.");
        }
        }
 
 
      return NULL;
      return NULL;
    }
    }
 
 
  /* We assume that the loop exit condition is at the end of the loop. i.e,
  /* We assume that the loop exit condition is at the end of the loop. i.e,
     that the loop is represented as a do-while (with a proper if-guard
     that the loop is represented as a do-while (with a proper if-guard
     before the loop if needed), where the loop header contains all the
     before the loop if needed), where the loop header contains all the
     executable statements, and the latch is empty.  */
     executable statements, and the latch is empty.  */
  if (!empty_block_p (loop->latch)
  if (!empty_block_p (loop->latch)
        || phi_nodes (loop->latch))
        || phi_nodes (loop->latch))
    {
    {
      if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
      if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
        fprintf (vect_dump, "not vectorized: unexpected loop form.");
        fprintf (vect_dump, "not vectorized: unexpected loop form.");
      return NULL;
      return NULL;
    }
    }
 
 
  /* Make sure there exists a single-predecessor exit bb:  */
  /* Make sure there exists a single-predecessor exit bb:  */
  if (!single_pred_p (loop->single_exit->dest))
  if (!single_pred_p (loop->single_exit->dest))
    {
    {
      edge e = loop->single_exit;
      edge e = loop->single_exit;
      if (!(e->flags & EDGE_ABNORMAL))
      if (!(e->flags & EDGE_ABNORMAL))
        {
        {
          split_loop_exit_edge (e);
          split_loop_exit_edge (e);
          if (vect_print_dump_info (REPORT_DETAILS))
          if (vect_print_dump_info (REPORT_DETAILS))
            fprintf (vect_dump, "split exit edge.");
            fprintf (vect_dump, "split exit edge.");
        }
        }
      else
      else
        {
        {
          if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
          if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
            fprintf (vect_dump, "not vectorized: abnormal loop exit edge.");
            fprintf (vect_dump, "not vectorized: abnormal loop exit edge.");
          return NULL;
          return NULL;
        }
        }
    }
    }
 
 
  if (empty_block_p (loop->header))
  if (empty_block_p (loop->header))
    {
    {
      if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
      if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
        fprintf (vect_dump, "not vectorized: empty loop.");
        fprintf (vect_dump, "not vectorized: empty loop.");
      return NULL;
      return NULL;
    }
    }
 
 
  loop_cond = vect_get_loop_niters (loop, &number_of_iterations);
  loop_cond = vect_get_loop_niters (loop, &number_of_iterations);
  if (!loop_cond)
  if (!loop_cond)
    {
    {
      if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
      if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
        fprintf (vect_dump, "not vectorized: complicated exit condition.");
        fprintf (vect_dump, "not vectorized: complicated exit condition.");
      return NULL;
      return NULL;
    }
    }
 
 
  if (!number_of_iterations)
  if (!number_of_iterations)
    {
    {
      if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
      if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
        fprintf (vect_dump,
        fprintf (vect_dump,
                 "not vectorized: number of iterations cannot be computed.");
                 "not vectorized: number of iterations cannot be computed.");
      return NULL;
      return NULL;
    }
    }
 
 
  if (chrec_contains_undetermined (number_of_iterations))
  if (chrec_contains_undetermined (number_of_iterations))
    {
    {
      if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
      if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
        fprintf (vect_dump, "Infinite number of iterations.");
        fprintf (vect_dump, "Infinite number of iterations.");
      return false;
      return false;
    }
    }
 
 
  loop_vinfo = new_loop_vec_info (loop);
  loop_vinfo = new_loop_vec_info (loop);
  LOOP_VINFO_NITERS (loop_vinfo) = number_of_iterations;
  LOOP_VINFO_NITERS (loop_vinfo) = number_of_iterations;
 
 
  if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo))
  if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo))
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        {
        {
          fprintf (vect_dump, "Symbolic number of iterations is ");
          fprintf (vect_dump, "Symbolic number of iterations is ");
          print_generic_expr (vect_dump, number_of_iterations, TDF_DETAILS);
          print_generic_expr (vect_dump, number_of_iterations, TDF_DETAILS);
        }
        }
    }
    }
  else
  else
  if (LOOP_VINFO_INT_NITERS (loop_vinfo) == 0)
  if (LOOP_VINFO_INT_NITERS (loop_vinfo) == 0)
    {
    {
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
        fprintf (vect_dump, "not vectorized: number of iterations = 0.");
        fprintf (vect_dump, "not vectorized: number of iterations = 0.");
      return NULL;
      return NULL;
    }
    }
 
 
  LOOP_VINFO_EXIT_COND (loop_vinfo) = loop_cond;
  LOOP_VINFO_EXIT_COND (loop_vinfo) = loop_cond;
 
 
  return loop_vinfo;
  return loop_vinfo;
}
}
 
 
 
 
/* Function vect_analyze_loop.
/* Function vect_analyze_loop.
 
 
   Apply a set of analyses on LOOP, and create a loop_vec_info struct
   Apply a set of analyses on LOOP, and create a loop_vec_info struct
   for it. The different analyses will record information in the
   for it. The different analyses will record information in the
   loop_vec_info struct.  */
   loop_vec_info struct.  */
loop_vec_info
loop_vec_info
vect_analyze_loop (struct loop *loop)
vect_analyze_loop (struct loop *loop)
{
{
  bool ok;
  bool ok;
  loop_vec_info loop_vinfo;
  loop_vec_info loop_vinfo;
 
 
  if (vect_print_dump_info (REPORT_DETAILS))
  if (vect_print_dump_info (REPORT_DETAILS))
    fprintf (vect_dump, "===== analyze_loop_nest =====");
    fprintf (vect_dump, "===== analyze_loop_nest =====");
 
 
  /* Check the CFG characteristics of the loop (nesting, entry/exit, etc.  */
  /* Check the CFG characteristics of the loop (nesting, entry/exit, etc.  */
 
 
  loop_vinfo = vect_analyze_loop_form (loop);
  loop_vinfo = vect_analyze_loop_form (loop);
  if (!loop_vinfo)
  if (!loop_vinfo)
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "bad loop form.");
        fprintf (vect_dump, "bad loop form.");
      return NULL;
      return NULL;
    }
    }
 
 
  /* Find all data references in the loop (which correspond to vdefs/vuses)
  /* Find all data references in the loop (which correspond to vdefs/vuses)
     and analyze their evolution in the loop.
     and analyze their evolution in the loop.
 
 
     FORNOW: Handle only simple, array references, which
     FORNOW: Handle only simple, array references, which
     alignment can be forced, and aligned pointer-references.  */
     alignment can be forced, and aligned pointer-references.  */
 
 
  ok = vect_analyze_data_refs (loop_vinfo);
  ok = vect_analyze_data_refs (loop_vinfo);
  if (!ok)
  if (!ok)
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "bad data references.");
        fprintf (vect_dump, "bad data references.");
      destroy_loop_vec_info (loop_vinfo);
      destroy_loop_vec_info (loop_vinfo);
      return NULL;
      return NULL;
    }
    }
 
 
  /* Classify all cross-iteration scalar data-flow cycles.
  /* Classify all cross-iteration scalar data-flow cycles.
     Cross-iteration cycles caused by virtual phis are analyzed separately.  */
     Cross-iteration cycles caused by virtual phis are analyzed separately.  */
 
 
  vect_analyze_scalar_cycles (loop_vinfo);
  vect_analyze_scalar_cycles (loop_vinfo);
 
 
  vect_pattern_recog (loop_vinfo);
  vect_pattern_recog (loop_vinfo);
 
 
  /* Data-flow analysis to detect stmts that do not need to be vectorized.  */
  /* Data-flow analysis to detect stmts that do not need to be vectorized.  */
 
 
  ok = vect_mark_stmts_to_be_vectorized (loop_vinfo);
  ok = vect_mark_stmts_to_be_vectorized (loop_vinfo);
  if (!ok)
  if (!ok)
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "unexpected pattern.");
        fprintf (vect_dump, "unexpected pattern.");
      destroy_loop_vec_info (loop_vinfo);
      destroy_loop_vec_info (loop_vinfo);
      return NULL;
      return NULL;
    }
    }
 
 
  /* Analyze the alignment of the data-refs in the loop.
  /* Analyze the alignment of the data-refs in the loop.
     Fail if a data reference is found that cannot be vectorized.  */
     Fail if a data reference is found that cannot be vectorized.  */
 
 
  ok = vect_analyze_data_refs_alignment (loop_vinfo);
  ok = vect_analyze_data_refs_alignment (loop_vinfo);
  if (!ok)
  if (!ok)
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "bad data alignment.");
        fprintf (vect_dump, "bad data alignment.");
      destroy_loop_vec_info (loop_vinfo);
      destroy_loop_vec_info (loop_vinfo);
      return NULL;
      return NULL;
    }
    }
 
 
  ok = vect_determine_vectorization_factor (loop_vinfo);
  ok = vect_determine_vectorization_factor (loop_vinfo);
  if (!ok)
  if (!ok)
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "can't determine vectorization factor.");
        fprintf (vect_dump, "can't determine vectorization factor.");
      destroy_loop_vec_info (loop_vinfo);
      destroy_loop_vec_info (loop_vinfo);
      return NULL;
      return NULL;
    }
    }
 
 
  /* Analyze data dependences between the data-refs in the loop.
  /* Analyze data dependences between the data-refs in the loop.
     FORNOW: fail at the first data dependence that we encounter.  */
     FORNOW: fail at the first data dependence that we encounter.  */
 
 
  ok = vect_analyze_data_ref_dependences (loop_vinfo);
  ok = vect_analyze_data_ref_dependences (loop_vinfo);
  if (!ok)
  if (!ok)
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "bad data dependence.");
        fprintf (vect_dump, "bad data dependence.");
      destroy_loop_vec_info (loop_vinfo);
      destroy_loop_vec_info (loop_vinfo);
      return NULL;
      return NULL;
    }
    }
 
 
  /* Analyze the access patterns of the data-refs in the loop (consecutive,
  /* Analyze the access patterns of the data-refs in the loop (consecutive,
     complex, etc.). FORNOW: Only handle consecutive access pattern.  */
     complex, etc.). FORNOW: Only handle consecutive access pattern.  */
 
 
  ok = vect_analyze_data_ref_accesses (loop_vinfo);
  ok = vect_analyze_data_ref_accesses (loop_vinfo);
  if (!ok)
  if (!ok)
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "bad data access.");
        fprintf (vect_dump, "bad data access.");
      destroy_loop_vec_info (loop_vinfo);
      destroy_loop_vec_info (loop_vinfo);
      return NULL;
      return NULL;
    }
    }
 
 
  /* This pass will decide on using loop versioning and/or loop peeling in
  /* This pass will decide on using loop versioning and/or loop peeling in
     order to enhance the alignment of data references in the loop.  */
     order to enhance the alignment of data references in the loop.  */
 
 
  ok = vect_enhance_data_refs_alignment (loop_vinfo);
  ok = vect_enhance_data_refs_alignment (loop_vinfo);
  if (!ok)
  if (!ok)
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "bad data alignment.");
        fprintf (vect_dump, "bad data alignment.");
      destroy_loop_vec_info (loop_vinfo);
      destroy_loop_vec_info (loop_vinfo);
      return NULL;
      return NULL;
    }
    }
 
 
  /* Scan all the operations in the loop and make sure they are
  /* Scan all the operations in the loop and make sure they are
     vectorizable.  */
     vectorizable.  */
 
 
  ok = vect_analyze_operations (loop_vinfo);
  ok = vect_analyze_operations (loop_vinfo);
  if (!ok)
  if (!ok)
    {
    {
      if (vect_print_dump_info (REPORT_DETAILS))
      if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "bad operation or unsupported loop bound.");
        fprintf (vect_dump, "bad operation or unsupported loop bound.");
      destroy_loop_vec_info (loop_vinfo);
      destroy_loop_vec_info (loop_vinfo);
      return NULL;
      return NULL;
    }
    }
 
 
  LOOP_VINFO_VECTORIZABLE_P (loop_vinfo) = 1;
  LOOP_VINFO_VECTORIZABLE_P (loop_vinfo) = 1;
 
 
  return loop_vinfo;
  return loop_vinfo;
}
}
 
 

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.