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/* Alias analysis for trees.

/* Alias analysis for trees.

   Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010

   Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010

   Free Software Foundation, Inc.

   Free Software Foundation, Inc.

   Contributed by Diego Novillo <dnovillo@redhat.com>

   Contributed by Diego Novillo <dnovillo@redhat.com>

This file is part of GCC.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify

GCC is free software; you can redistribute it and/or modify

it under the terms of the GNU General Public License as published by

it under the terms of the GNU General Public License as published by

the Free Software Foundation; either version 3, or (at your option)

the Free Software Foundation; either version 3, or (at your option)

any later version.

any later version.

GCC is distributed in the hope that it will be useful,

GCC is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

GNU General Public License for more details.

GNU General Public License 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 "tree.h"

#include "tree.h"

#include "rtl.h"

#include "rtl.h"

#include "tm_p.h"

#include "tm_p.h"

#include "hard-reg-set.h"

#include "hard-reg-set.h"

#include "basic-block.h"

#include "basic-block.h"

#include "timevar.h"

#include "timevar.h"

#include "expr.h"

#include "expr.h"

#include "ggc.h"

#include "ggc.h"

#include "langhooks.h"

#include "langhooks.h"

#include "flags.h"

#include "flags.h"

#include "function.h"

#include "function.h"

#include "diagnostic.h"

#include "diagnostic.h"

#include "tree-dump.h"

#include "tree-dump.h"

#include "gimple.h"

#include "gimple.h"

#include "tree-flow.h"

#include "tree-flow.h"

#include "tree-inline.h"

#include "tree-inline.h"

#include "tree-pass.h"

#include "tree-pass.h"

#include "convert.h"

#include "convert.h"

#include "params.h"

#include "params.h"

#include "ipa-type-escape.h"

#include "ipa-type-escape.h"

#include "vec.h"

#include "vec.h"

#include "bitmap.h"

#include "bitmap.h"

#include "vecprim.h"

#include "vecprim.h"

#include "pointer-set.h"

#include "pointer-set.h"

#include "alloc-pool.h"

#include "alloc-pool.h"

#include "tree-ssa-alias.h"

#include "tree-ssa-alias.h"

/* Broad overview of how alias analysis on gimple works:

/* Broad overview of how alias analysis on gimple works:

   Statements clobbering or using memory are linked through the

   Statements clobbering or using memory are linked through the

   virtual operand factored use-def chain.  The virtual operand

   virtual operand factored use-def chain.  The virtual operand

   is unique per function, its symbol is accessible via gimple_vop (cfun).

   is unique per function, its symbol is accessible via gimple_vop (cfun).

   Virtual operands are used for efficiently walking memory statements

   Virtual operands are used for efficiently walking memory statements

   in the gimple IL and are useful for things like value-numbering as

   in the gimple IL and are useful for things like value-numbering as

   a generation count for memory references.

   a generation count for memory references.

   SSA_NAME pointers may have associated points-to information

   SSA_NAME pointers may have associated points-to information

   accessible via the SSA_NAME_PTR_INFO macro.  Flow-insensitive

   accessible via the SSA_NAME_PTR_INFO macro.  Flow-insensitive

   points-to information is (re-)computed by the TODO_rebuild_alias

   points-to information is (re-)computed by the TODO_rebuild_alias

   pass manager todo.  Points-to information is also used for more

   pass manager todo.  Points-to information is also used for more

   precise tracking of call-clobbered and call-used variables and

   precise tracking of call-clobbered and call-used variables and

   related disambiguations.

   related disambiguations.

   This file contains functions for disambiguating memory references,

   This file contains functions for disambiguating memory references,

   the so called alias-oracle and tools for walking of the gimple IL.

   the so called alias-oracle and tools for walking of the gimple IL.

   The main alias-oracle entry-points are

   The main alias-oracle entry-points are

   bool stmt_may_clobber_ref_p (gimple, tree)

   bool stmt_may_clobber_ref_p (gimple, tree)

     This function queries if a statement may invalidate (parts of)

     This function queries if a statement may invalidate (parts of)

     the memory designated by the reference tree argument.

     the memory designated by the reference tree argument.

   bool ref_maybe_used_by_stmt_p (gimple, tree)

   bool ref_maybe_used_by_stmt_p (gimple, tree)

     This function queries if a statement may need (parts of) the

     This function queries if a statement may need (parts of) the

     memory designated by the reference tree argument.

     memory designated by the reference tree argument.

   There are variants of these functions that only handle the call

   There are variants of these functions that only handle the call

   part of a statement, call_may_clobber_ref_p and ref_maybe_used_by_call_p.

   part of a statement, call_may_clobber_ref_p and ref_maybe_used_by_call_p.

   Note that these do not disambiguate against a possible call lhs.

   Note that these do not disambiguate against a possible call lhs.

   bool refs_may_alias_p (tree, tree)

   bool refs_may_alias_p (tree, tree)

     This function tries to disambiguate two reference trees.

     This function tries to disambiguate two reference trees.

   bool ptr_deref_may_alias_global_p (tree)

   bool ptr_deref_may_alias_global_p (tree)

     This function queries if dereferencing a pointer variable may

     This function queries if dereferencing a pointer variable may

     alias global memory.

     alias global memory.

   More low-level disambiguators are available and documented in

   More low-level disambiguators are available and documented in

   this file.  Low-level disambiguators dealing with points-to

   this file.  Low-level disambiguators dealing with points-to

   information are in tree-ssa-structalias.c.  */

   information are in tree-ssa-structalias.c.  */

/* Query statistics for the different low-level disambiguators.

/* Query statistics for the different low-level disambiguators.

   A high-level query may trigger multiple of them.  */

   A high-level query may trigger multiple of them.  */

static struct {

static struct {

  unsigned HOST_WIDE_INT refs_may_alias_p_may_alias;

  unsigned HOST_WIDE_INT refs_may_alias_p_may_alias;

  unsigned HOST_WIDE_INT refs_may_alias_p_no_alias;

  unsigned HOST_WIDE_INT refs_may_alias_p_no_alias;

  unsigned HOST_WIDE_INT ref_maybe_used_by_call_p_may_alias;

  unsigned HOST_WIDE_INT ref_maybe_used_by_call_p_may_alias;

  unsigned HOST_WIDE_INT ref_maybe_used_by_call_p_no_alias;

  unsigned HOST_WIDE_INT ref_maybe_used_by_call_p_no_alias;

  unsigned HOST_WIDE_INT call_may_clobber_ref_p_may_alias;

  unsigned HOST_WIDE_INT call_may_clobber_ref_p_may_alias;

  unsigned HOST_WIDE_INT call_may_clobber_ref_p_no_alias;

  unsigned HOST_WIDE_INT call_may_clobber_ref_p_no_alias;

} alias_stats;

} alias_stats;

void

void

dump_alias_stats (FILE *s)

dump_alias_stats (FILE *s)

{

{

  fprintf (s, "\nAlias oracle query stats:\n");

  fprintf (s, "\nAlias oracle query stats:\n");

  fprintf (s, "  refs_may_alias_p: "

  fprintf (s, "  refs_may_alias_p: "

           HOST_WIDE_INT_PRINT_DEC" disambiguations, "

           HOST_WIDE_INT_PRINT_DEC" disambiguations, "

           HOST_WIDE_INT_PRINT_DEC" queries\n",

           HOST_WIDE_INT_PRINT_DEC" queries\n",

           alias_stats.refs_may_alias_p_no_alias,

           alias_stats.refs_may_alias_p_no_alias,

           alias_stats.refs_may_alias_p_no_alias

           alias_stats.refs_may_alias_p_no_alias

           + alias_stats.refs_may_alias_p_may_alias);

           + alias_stats.refs_may_alias_p_may_alias);

  fprintf (s, "  ref_maybe_used_by_call_p: "

  fprintf (s, "  ref_maybe_used_by_call_p: "

           HOST_WIDE_INT_PRINT_DEC" disambiguations, "

           HOST_WIDE_INT_PRINT_DEC" disambiguations, "

           HOST_WIDE_INT_PRINT_DEC" queries\n",

           HOST_WIDE_INT_PRINT_DEC" queries\n",

           alias_stats.ref_maybe_used_by_call_p_no_alias,

           alias_stats.ref_maybe_used_by_call_p_no_alias,

           alias_stats.refs_may_alias_p_no_alias

           alias_stats.refs_may_alias_p_no_alias

           + alias_stats.ref_maybe_used_by_call_p_may_alias);

           + alias_stats.ref_maybe_used_by_call_p_may_alias);

  fprintf (s, "  call_may_clobber_ref_p: "

  fprintf (s, "  call_may_clobber_ref_p: "

           HOST_WIDE_INT_PRINT_DEC" disambiguations, "

           HOST_WIDE_INT_PRINT_DEC" disambiguations, "

           HOST_WIDE_INT_PRINT_DEC" queries\n",

           HOST_WIDE_INT_PRINT_DEC" queries\n",

           alias_stats.call_may_clobber_ref_p_no_alias,

           alias_stats.call_may_clobber_ref_p_no_alias,

           alias_stats.call_may_clobber_ref_p_no_alias

           alias_stats.call_may_clobber_ref_p_no_alias

           + alias_stats.call_may_clobber_ref_p_may_alias);

           + alias_stats.call_may_clobber_ref_p_may_alias);

}

}

/* Return true, if dereferencing PTR may alias with a global variable.  */

/* Return true, if dereferencing PTR may alias with a global variable.  */

bool

bool

ptr_deref_may_alias_global_p (tree ptr)

ptr_deref_may_alias_global_p (tree ptr)

{

{

  struct ptr_info_def *pi;

  struct ptr_info_def *pi;

  /* If we end up with a pointer constant here that may point

  /* If we end up with a pointer constant here that may point

     to global memory.  */

     to global memory.  */

  if (TREE_CODE (ptr) != SSA_NAME)

  if (TREE_CODE (ptr) != SSA_NAME)

    return true;

    return true;

  pi = SSA_NAME_PTR_INFO (ptr);

  pi = SSA_NAME_PTR_INFO (ptr);

  /* If we do not have points-to information for this variable,

  /* If we do not have points-to information for this variable,

     we have to punt.  */

     we have to punt.  */

  if (!pi)

  if (!pi)

    return true;

    return true;

  /* ???  This does not use TBAA to prune globals ptr may not access.  */

  /* ???  This does not use TBAA to prune globals ptr may not access.  */

  return pt_solution_includes_global (&pi->pt);

  return pt_solution_includes_global (&pi->pt);

}

}

/* Return true if dereferencing PTR may alias DECL.

/* Return true if dereferencing PTR may alias DECL.

   The caller is responsible for applying TBAA to see if PTR

   The caller is responsible for applying TBAA to see if PTR

   may access DECL at all.  */

   may access DECL at all.  */

static bool

static bool

ptr_deref_may_alias_decl_p (tree ptr, tree decl)

ptr_deref_may_alias_decl_p (tree ptr, tree decl)

{

{

  struct ptr_info_def *pi;

  struct ptr_info_def *pi;

  gcc_assert ((TREE_CODE (ptr) == SSA_NAME

  gcc_assert ((TREE_CODE (ptr) == SSA_NAME

               || TREE_CODE (ptr) == ADDR_EXPR

               || TREE_CODE (ptr) == ADDR_EXPR

               || TREE_CODE (ptr) == INTEGER_CST)

               || TREE_CODE (ptr) == INTEGER_CST)

              && (TREE_CODE (decl) == VAR_DECL

              && (TREE_CODE (decl) == VAR_DECL

                  || TREE_CODE (decl) == PARM_DECL

                  || TREE_CODE (decl) == PARM_DECL

                  || TREE_CODE (decl) == RESULT_DECL));

                  || TREE_CODE (decl) == RESULT_DECL));

  /* Non-aliased variables can not be pointed to.  */

  /* Non-aliased variables can not be pointed to.  */

  if (!may_be_aliased (decl))

  if (!may_be_aliased (decl))

    return false;

    return false;

  /* ADDR_EXPR pointers either just offset another pointer or directly

  /* ADDR_EXPR pointers either just offset another pointer or directly

     specify the pointed-to set.  */

     specify the pointed-to set.  */

  if (TREE_CODE (ptr) == ADDR_EXPR)

  if (TREE_CODE (ptr) == ADDR_EXPR)

    {

    {

      tree base = get_base_address (TREE_OPERAND (ptr, 0));

      tree base = get_base_address (TREE_OPERAND (ptr, 0));

      if (base

      if (base

          && INDIRECT_REF_P (base))

          && INDIRECT_REF_P (base))

        ptr = TREE_OPERAND (base, 0);

        ptr = TREE_OPERAND (base, 0);

      else if (base

      else if (base

               && SSA_VAR_P (base))

               && SSA_VAR_P (base))

        return operand_equal_p (base, decl, 0);

        return operand_equal_p (base, decl, 0);

      else if (base

      else if (base

               && CONSTANT_CLASS_P (base))

               && CONSTANT_CLASS_P (base))

        return false;

        return false;

      else

      else

        return true;

        return true;

    }

    }

  /* We can end up with dereferencing constant pointers.

  /* We can end up with dereferencing constant pointers.

     Just bail out in this case.  */

     Just bail out in this case.  */

  if (TREE_CODE (ptr) == INTEGER_CST)

  if (TREE_CODE (ptr) == INTEGER_CST)

    return true;

    return true;

  /* If we do not have useful points-to information for this pointer

  /* If we do not have useful points-to information for this pointer

     we cannot disambiguate anything else.  */

     we cannot disambiguate anything else.  */

  pi = SSA_NAME_PTR_INFO (ptr);

  pi = SSA_NAME_PTR_INFO (ptr);

  if (!pi)

  if (!pi)

    return true;

    return true;

  /* If the decl can be used as a restrict tag and we have a restrict

  /* If the decl can be used as a restrict tag and we have a restrict

     pointer and that pointers points-to set doesn't contain this decl

     pointer and that pointers points-to set doesn't contain this decl

     then they can't alias.  */

     then they can't alias.  */

  if (DECL_RESTRICTED_P (decl)

  if (DECL_RESTRICTED_P (decl)

      && TYPE_RESTRICT (TREE_TYPE (ptr))

      && TYPE_RESTRICT (TREE_TYPE (ptr))

      && pi->pt.vars_contains_restrict)

      && pi->pt.vars_contains_restrict)

    return bitmap_bit_p (pi->pt.vars, DECL_UID (decl));

    return bitmap_bit_p (pi->pt.vars, DECL_UID (decl));

  return pt_solution_includes (&pi->pt, decl);

  return pt_solution_includes (&pi->pt, decl);

}

}

/* Return true if dereferenced PTR1 and PTR2 may alias.

/* Return true if dereferenced PTR1 and PTR2 may alias.

   The caller is responsible for applying TBAA to see if accesses

   The caller is responsible for applying TBAA to see if accesses

   through PTR1 and PTR2 may conflict at all.  */

   through PTR1 and PTR2 may conflict at all.  */

static bool

static bool

ptr_derefs_may_alias_p (tree ptr1, tree ptr2)

ptr_derefs_may_alias_p (tree ptr1, tree ptr2)

{

{

  struct ptr_info_def *pi1, *pi2;

  struct ptr_info_def *pi1, *pi2;

  gcc_assert ((TREE_CODE (ptr1) == SSA_NAME

  gcc_assert ((TREE_CODE (ptr1) == SSA_NAME

               || TREE_CODE (ptr1) == ADDR_EXPR

               || TREE_CODE (ptr1) == ADDR_EXPR

               || TREE_CODE (ptr1) == INTEGER_CST)

               || TREE_CODE (ptr1) == INTEGER_CST)

              && (TREE_CODE (ptr2) == SSA_NAME

              && (TREE_CODE (ptr2) == SSA_NAME

                  || TREE_CODE (ptr2) == ADDR_EXPR

                  || TREE_CODE (ptr2) == ADDR_EXPR

                  || TREE_CODE (ptr2) == INTEGER_CST));

                  || TREE_CODE (ptr2) == INTEGER_CST));

  /* ADDR_EXPR pointers either just offset another pointer or directly

  /* ADDR_EXPR pointers either just offset another pointer or directly

     specify the pointed-to set.  */

     specify the pointed-to set.  */

  if (TREE_CODE (ptr1) == ADDR_EXPR)

  if (TREE_CODE (ptr1) == ADDR_EXPR)

    {

    {

      tree base = get_base_address (TREE_OPERAND (ptr1, 0));

      tree base = get_base_address (TREE_OPERAND (ptr1, 0));

      if (base

      if (base

          && INDIRECT_REF_P (base))

          && INDIRECT_REF_P (base))

        ptr1 = TREE_OPERAND (base, 0);

        ptr1 = TREE_OPERAND (base, 0);

      else if (base

      else if (base

               && SSA_VAR_P (base))

               && SSA_VAR_P (base))

        return ptr_deref_may_alias_decl_p (ptr2, base);

        return ptr_deref_may_alias_decl_p (ptr2, base);

      else

      else

        return true;

        return true;

    }

    }

  if (TREE_CODE (ptr2) == ADDR_EXPR)

  if (TREE_CODE (ptr2) == ADDR_EXPR)

    {

    {

      tree base = get_base_address (TREE_OPERAND (ptr2, 0));

      tree base = get_base_address (TREE_OPERAND (ptr2, 0));

      if (base

      if (base

          && INDIRECT_REF_P (base))

          && INDIRECT_REF_P (base))

        ptr2 = TREE_OPERAND (base, 0);

        ptr2 = TREE_OPERAND (base, 0);

      else if (base

      else if (base

               && SSA_VAR_P (base))

               && SSA_VAR_P (base))

        return ptr_deref_may_alias_decl_p (ptr1, base);

        return ptr_deref_may_alias_decl_p (ptr1, base);

      else

      else

        return true;

        return true;

    }

    }

  /* We can end up with dereferencing constant pointers.

  /* We can end up with dereferencing constant pointers.

     Just bail out in this case.  */

     Just bail out in this case.  */

  if (TREE_CODE (ptr1) == INTEGER_CST

  if (TREE_CODE (ptr1) == INTEGER_CST

      || TREE_CODE (ptr2) == INTEGER_CST)

      || TREE_CODE (ptr2) == INTEGER_CST)

    return true;

    return true;

  /* We may end up with two empty points-to solutions for two same pointers.

  /* We may end up with two empty points-to solutions for two same pointers.

     In this case we still want to say both pointers alias, so shortcut

     In this case we still want to say both pointers alias, so shortcut

     that here.  */

     that here.  */

  if (ptr1 == ptr2)

  if (ptr1 == ptr2)

    return true;

    return true;

  /* If we do not have useful points-to information for either pointer

  /* If we do not have useful points-to information for either pointer

     we cannot disambiguate anything else.  */

     we cannot disambiguate anything else.  */

  pi1 = SSA_NAME_PTR_INFO (ptr1);

  pi1 = SSA_NAME_PTR_INFO (ptr1);

  pi2 = SSA_NAME_PTR_INFO (ptr2);

  pi2 = SSA_NAME_PTR_INFO (ptr2);

  if (!pi1 || !pi2)

  if (!pi1 || !pi2)

    return true;

    return true;

  /* If both pointers are restrict-qualified try to disambiguate

  /* If both pointers are restrict-qualified try to disambiguate

     with restrict information.  */

     with restrict information.  */

  if (TYPE_RESTRICT (TREE_TYPE (ptr1))

  if (TYPE_RESTRICT (TREE_TYPE (ptr1))

      && TYPE_RESTRICT (TREE_TYPE (ptr2))

      && TYPE_RESTRICT (TREE_TYPE (ptr2))

      && !pt_solutions_same_restrict_base (&pi1->pt, &pi2->pt))

      && !pt_solutions_same_restrict_base (&pi1->pt, &pi2->pt))

    return false;

    return false;

  /* ???  This does not use TBAA to prune decls from the intersection

  /* ???  This does not use TBAA to prune decls from the intersection

     that not both pointers may access.  */

     that not both pointers may access.  */

  return pt_solutions_intersect (&pi1->pt, &pi2->pt);

  return pt_solutions_intersect (&pi1->pt, &pi2->pt);

}

}

/* Return true if dereferencing PTR may alias *REF.

/* Return true if dereferencing PTR may alias *REF.

   The caller is responsible for applying TBAA to see if PTR

   The caller is responsible for applying TBAA to see if PTR

   may access *REF at all.  */

   may access *REF at all.  */

static bool

static bool

ptr_deref_may_alias_ref_p_1 (tree ptr, ao_ref *ref)

ptr_deref_may_alias_ref_p_1 (tree ptr, ao_ref *ref)

{

{

  tree base = ao_ref_base (ref);

  tree base = ao_ref_base (ref);

  if (INDIRECT_REF_P (base))

  if (INDIRECT_REF_P (base))

    return ptr_derefs_may_alias_p (ptr, TREE_OPERAND (base, 0));

    return ptr_derefs_may_alias_p (ptr, TREE_OPERAND (base, 0));

  else if (SSA_VAR_P (base))

  else if (SSA_VAR_P (base))

    return ptr_deref_may_alias_decl_p (ptr, base);

    return ptr_deref_may_alias_decl_p (ptr, base);

  return true;

  return true;

}

}

/* Dump alias information on FILE.  */

/* Dump alias information on FILE.  */

void

void

dump_alias_info (FILE *file)

dump_alias_info (FILE *file)

{

{

  size_t i;

  size_t i;

  const char *funcname

  const char *funcname

    = lang_hooks.decl_printable_name (current_function_decl, 2);

    = lang_hooks.decl_printable_name (current_function_decl, 2);

  referenced_var_iterator rvi;

  referenced_var_iterator rvi;

  tree var;

  tree var;

  fprintf (file, "\n\nAlias information for %s\n\n", funcname);

  fprintf (file, "\n\nAlias information for %s\n\n", funcname);

  fprintf (file, "Aliased symbols\n\n");

  fprintf (file, "Aliased symbols\n\n");

  FOR_EACH_REFERENCED_VAR (var, rvi)

  FOR_EACH_REFERENCED_VAR (var, rvi)

    {

    {

      if (may_be_aliased (var))

      if (may_be_aliased (var))

        dump_variable (file, var);

        dump_variable (file, var);

    }

    }

  fprintf (file, "\nCall clobber information\n");

  fprintf (file, "\nCall clobber information\n");

  fprintf (file, "\nESCAPED");

  fprintf (file, "\nESCAPED");

  dump_points_to_solution (file, &cfun->gimple_df->escaped);

  dump_points_to_solution (file, &cfun->gimple_df->escaped);

  fprintf (file, "\nCALLUSED");

  fprintf (file, "\nCALLUSED");

  dump_points_to_solution (file, &cfun->gimple_df->callused);

  dump_points_to_solution (file, &cfun->gimple_df->callused);

  fprintf (file, "\n\nFlow-insensitive points-to information\n\n");

  fprintf (file, "\n\nFlow-insensitive points-to information\n\n");

  for (i = 1; i < num_ssa_names; i++)

  for (i = 1; i < num_ssa_names; i++)

    {

    {

      tree ptr = ssa_name (i);

      tree ptr = ssa_name (i);

      struct ptr_info_def *pi;

      struct ptr_info_def *pi;

      if (ptr == NULL_TREE

      if (ptr == NULL_TREE

          || SSA_NAME_IN_FREE_LIST (ptr))

          || SSA_NAME_IN_FREE_LIST (ptr))

        continue;

        continue;

      pi = SSA_NAME_PTR_INFO (ptr);

      pi = SSA_NAME_PTR_INFO (ptr);

      if (pi)

      if (pi)

        dump_points_to_info_for (file, ptr);

        dump_points_to_info_for (file, ptr);

    }

    }

  fprintf (file, "\n");

  fprintf (file, "\n");

}

}

/* Dump alias information on stderr.  */

/* Dump alias information on stderr.  */

void

void

debug_alias_info (void)

debug_alias_info (void)

{

{

  dump_alias_info (stderr);

  dump_alias_info (stderr);

}

}

/* Return the alias information associated with pointer T.  It creates a

/* Return the alias information associated with pointer T.  It creates a

   new instance if none existed.  */

   new instance if none existed.  */

struct ptr_info_def *

struct ptr_info_def *

get_ptr_info (tree t)

get_ptr_info (tree t)

{

{

  struct ptr_info_def *pi;

  struct ptr_info_def *pi;

  gcc_assert (POINTER_TYPE_P (TREE_TYPE (t)));

  gcc_assert (POINTER_TYPE_P (TREE_TYPE (t)));

  pi = SSA_NAME_PTR_INFO (t);

  pi = SSA_NAME_PTR_INFO (t);

  if (pi == NULL)

  if (pi == NULL)

    {

    {

      pi = GGC_CNEW (struct ptr_info_def);

      pi = GGC_CNEW (struct ptr_info_def);

      pt_solution_reset (&pi->pt);

      pt_solution_reset (&pi->pt);

      SSA_NAME_PTR_INFO (t) = pi;

      SSA_NAME_PTR_INFO (t) = pi;

    }

    }

  return pi;

  return pi;

}

}

/* Dump the points-to set *PT into FILE.  */

/* Dump the points-to set *PT into FILE.  */

void

void

dump_points_to_solution (FILE *file, struct pt_solution *pt)

dump_points_to_solution (FILE *file, struct pt_solution *pt)

{

{

  if (pt->anything)

  if (pt->anything)

    fprintf (file, ", points-to anything");

    fprintf (file, ", points-to anything");

  if (pt->nonlocal)

  if (pt->nonlocal)

    fprintf (file, ", points-to non-local");

    fprintf (file, ", points-to non-local");

  if (pt->escaped)

  if (pt->escaped)

    fprintf (file, ", points-to escaped");

    fprintf (file, ", points-to escaped");

  if (pt->null)

  if (pt->null)

    fprintf (file, ", points-to NULL");

    fprintf (file, ", points-to NULL");

  if (pt->vars)

  if (pt->vars)

    {

    {

      fprintf (file, ", points-to vars: ");

      fprintf (file, ", points-to vars: ");

      dump_decl_set (file, pt->vars);

      dump_decl_set (file, pt->vars);

      if (pt->vars_contains_global)

      if (pt->vars_contains_global)

        fprintf (file, " (includes global vars)");

        fprintf (file, " (includes global vars)");

    }

    }

}

}

/* Dump points-to information for SSA_NAME PTR into FILE.  */

/* Dump points-to information for SSA_NAME PTR into FILE.  */

void

void

dump_points_to_info_for (FILE *file, tree ptr)

dump_points_to_info_for (FILE *file, tree ptr)

{

{

  struct ptr_info_def *pi = SSA_NAME_PTR_INFO (ptr);

  struct ptr_info_def *pi = SSA_NAME_PTR_INFO (ptr);

  print_generic_expr (file, ptr, dump_flags);

  print_generic_expr (file, ptr, dump_flags);

  if (pi)

  if (pi)

    dump_points_to_solution (file, &pi->pt);

    dump_points_to_solution (file, &pi->pt);

  else

  else

    fprintf (file, ", points-to anything");

    fprintf (file, ", points-to anything");

  fprintf (file, "\n");

  fprintf (file, "\n");

}

}

/* Dump points-to information for VAR into stderr.  */

/* Dump points-to information for VAR into stderr.  */

void

void

debug_points_to_info_for (tree var)

debug_points_to_info_for (tree var)

{

{

  dump_points_to_info_for (stderr, var);

  dump_points_to_info_for (stderr, var);

}

}

/* Initializes the alias-oracle reference representation *R from REF.  */

/* Initializes the alias-oracle reference representation *R from REF.  */

void

void

ao_ref_init (ao_ref *r, tree ref)

ao_ref_init (ao_ref *r, tree ref)

{

{

  r->ref = ref;

  r->ref = ref;

  r->base = NULL_TREE;

  r->base = NULL_TREE;

  r->offset = 0;

  r->offset = 0;

  r->size = -1;

  r->size = -1;

  r->max_size = -1;

  r->max_size = -1;

  r->ref_alias_set = -1;

  r->ref_alias_set = -1;

  r->base_alias_set = -1;

  r->base_alias_set = -1;

}

}

/* Returns the base object of the memory reference *REF.  */

/* Returns the base object of the memory reference *REF.  */

tree

tree

ao_ref_base (ao_ref *ref)

ao_ref_base (ao_ref *ref)

{

{

  if (ref->base)

  if (ref->base)

    return ref->base;

    return ref->base;

  ref->base = get_ref_base_and_extent (ref->ref, &ref->offset, &ref->size,

  ref->base = get_ref_base_and_extent (ref->ref, &ref->offset, &ref->size,

                                       &ref->max_size);

                                       &ref->max_size);

  return ref->base;

  return ref->base;

}

}

/* Returns the base object alias set of the memory reference *REF.  */

/* Returns the base object alias set of the memory reference *REF.  */

static alias_set_type ATTRIBUTE_UNUSED

static alias_set_type ATTRIBUTE_UNUSED

ao_ref_base_alias_set (ao_ref *ref)

ao_ref_base_alias_set (ao_ref *ref)

{

{

  if (ref->base_alias_set != -1)

  if (ref->base_alias_set != -1)

    return ref->base_alias_set;

    return ref->base_alias_set;

  ref->base_alias_set = get_alias_set (ao_ref_base (ref));

  ref->base_alias_set = get_alias_set (ao_ref_base (ref));

  return ref->base_alias_set;

  return ref->base_alias_set;

}

}

/* Returns the reference alias set of the memory reference *REF.  */

/* Returns the reference alias set of the memory reference *REF.  */

alias_set_type

alias_set_type

ao_ref_alias_set (ao_ref *ref)

ao_ref_alias_set (ao_ref *ref)

{

{

  if (ref->ref_alias_set != -1)

  if (ref->ref_alias_set != -1)

    return ref->ref_alias_set;

    return ref->ref_alias_set;

  ref->ref_alias_set = get_alias_set (ref->ref);

  ref->ref_alias_set = get_alias_set (ref->ref);

  return ref->ref_alias_set;

  return ref->ref_alias_set;

}

}

/* Init an alias-oracle reference representation from a gimple pointer

/* Init an alias-oracle reference representation from a gimple pointer

   PTR and a gimple size SIZE in bytes.  If SIZE is NULL_TREE the the

   PTR and a gimple size SIZE in bytes.  If SIZE is NULL_TREE the the

   size is assumed to be unknown.  The access is assumed to be only

   size is assumed to be unknown.  The access is assumed to be only

   to or after of the pointer target, not before it.  */

   to or after of the pointer target, not before it.  */

void

void

ao_ref_init_from_ptr_and_size (ao_ref *ref, tree ptr, tree size)

ao_ref_init_from_ptr_and_size (ao_ref *ref, tree ptr, tree size)

{

{

  HOST_WIDE_INT t1, t2;

  HOST_WIDE_INT t1, t2;

  ref->ref = NULL_TREE;

  ref->ref = NULL_TREE;

  if (TREE_CODE (ptr) == ADDR_EXPR)

  if (TREE_CODE (ptr) == ADDR_EXPR)

    ref->base = get_ref_base_and_extent (TREE_OPERAND (ptr, 0),

    ref->base = get_ref_base_and_extent (TREE_OPERAND (ptr, 0),

                                         &ref->offset, &t1, &t2);

                                         &ref->offset, &t1, &t2);

  else

  else

    {

    {

      ref->base = build1 (INDIRECT_REF, char_type_node, ptr);

      ref->base = build1 (INDIRECT_REF, char_type_node, ptr);

      ref->offset = 0;

      ref->offset = 0;

    }

    }

  if (size

  if (size

      && host_integerp (size, 0)

      && host_integerp (size, 0)

      && TREE_INT_CST_LOW (size) * 8 / 8 == TREE_INT_CST_LOW (size))

      && TREE_INT_CST_LOW (size) * 8 / 8 == TREE_INT_CST_LOW (size))

    ref->max_size = ref->size = TREE_INT_CST_LOW (size) * 8;

    ref->max_size = ref->size = TREE_INT_CST_LOW (size) * 8;

  else

  else

    ref->max_size = ref->size = -1;

    ref->max_size = ref->size = -1;

  ref->ref_alias_set = 0;

  ref->ref_alias_set = 0;

  ref->base_alias_set = 0;

  ref->base_alias_set = 0;

}

}

/* Return 1 if TYPE1 and TYPE2 are to be considered equivalent for the

/* Return 1 if TYPE1 and TYPE2 are to be considered equivalent for the

   purpose of TBAA.  Return 0 if they are distinct and -1 if we cannot

   purpose of TBAA.  Return 0 if they are distinct and -1 if we cannot

   decide.  */

   decide.  */

static inline int

static inline int

same_type_for_tbaa (tree type1, tree type2)

same_type_for_tbaa (tree type1, tree type2)

{

{

  type1 = TYPE_MAIN_VARIANT (type1);

  type1 = TYPE_MAIN_VARIANT (type1);

  type2 = TYPE_MAIN_VARIANT (type2);

  type2 = TYPE_MAIN_VARIANT (type2);

  /* If we would have to do structural comparison bail out.  */

  /* If we would have to do structural comparison bail out.  */

  if (TYPE_STRUCTURAL_EQUALITY_P (type1)

  if (TYPE_STRUCTURAL_EQUALITY_P (type1)

      || TYPE_STRUCTURAL_EQUALITY_P (type2))

      || TYPE_STRUCTURAL_EQUALITY_P (type2))

    return -1;

    return -1;

  /* Compare the canonical types.  */

  /* Compare the canonical types.  */

  if (TYPE_CANONICAL (type1) == TYPE_CANONICAL (type2))

  if (TYPE_CANONICAL (type1) == TYPE_CANONICAL (type2))

    return 1;

    return 1;

  /* ??? Array types are not properly unified in all cases as we have

  /* ??? Array types are not properly unified in all cases as we have

     spurious changes in the index types for example.  Removing this

     spurious changes in the index types for example.  Removing this

     causes all sorts of problems with the Fortran frontend.  */

     causes all sorts of problems with the Fortran frontend.  */

  if (TREE_CODE (type1) == ARRAY_TYPE

  if (TREE_CODE (type1) == ARRAY_TYPE

      && TREE_CODE (type2) == ARRAY_TYPE)

      && TREE_CODE (type2) == ARRAY_TYPE)

    return -1;

    return -1;

  /* ??? In Ada, an lvalue of an unconstrained type can be used to access an

  /* ??? In Ada, an lvalue of an unconstrained type can be used to access an

     object of one of its constrained subtypes, e.g. when a function with an

     object of one of its constrained subtypes, e.g. when a function with an

     unconstrained parameter passed by reference is called on an object and

     unconstrained parameter passed by reference is called on an object and

     inlined.  But, even in the case of a fixed size, type and subtypes are

     inlined.  But, even in the case of a fixed size, type and subtypes are

     not equivalent enough as to share the same TYPE_CANONICAL, since this

     not equivalent enough as to share the same TYPE_CANONICAL, since this

     would mean that conversions between them are useless, whereas they are

     would mean that conversions between them are useless, whereas they are

     not (e.g. type and subtypes can have different modes).  So, in the end,

     not (e.g. type and subtypes can have different modes).  So, in the end,

     they are only guaranteed to have the same alias set.  */

     they are only guaranteed to have the same alias set.  */

  if (get_alias_set (type1) == get_alias_set (type2))

  if (get_alias_set (type1) == get_alias_set (type2))

    return -1;

    return -1;

  /* The types are known to be not equal.  */

  /* The types are known to be not equal.  */

  return 0;

  return 0;

}

}

/* Determine if the two component references REF1 and REF2 which are

/* Determine if the two component references REF1 and REF2 which are

   based on access types TYPE1 and TYPE2 and of which at least one is based

   based on access types TYPE1 and TYPE2 and of which at least one is based

   on an indirect reference may alias.  REF2 is the only one that can

   on an indirect reference may alias.  REF2 is the only one that can

   be a decl in which case REF2_IS_DECL is true.

   be a decl in which case REF2_IS_DECL is true.

   REF1_ALIAS_SET, BASE1_ALIAS_SET, REF2_ALIAS_SET and BASE2_ALIAS_SET

   REF1_ALIAS_SET, BASE1_ALIAS_SET, REF2_ALIAS_SET and BASE2_ALIAS_SET

   are the respective alias sets.  */

   are the respective alias sets.  */

static bool

static bool

aliasing_component_refs_p (tree ref1, tree type1,

aliasing_component_refs_p (tree ref1, tree type1,

                           alias_set_type ref1_alias_set,

                           alias_set_type ref1_alias_set,

                           alias_set_type base1_alias_set,

                           alias_set_type base1_alias_set,

                           HOST_WIDE_INT offset1, HOST_WIDE_INT max_size1,

                           HOST_WIDE_INT offset1, HOST_WIDE_INT max_size1,

                           tree ref2, tree type2,

                           tree ref2, tree type2,

                           alias_set_type ref2_alias_set,

                           alias_set_type ref2_alias_set,

                           alias_set_type base2_alias_set,

                           alias_set_type base2_alias_set,

                           HOST_WIDE_INT offset2, HOST_WIDE_INT max_size2,

                           HOST_WIDE_INT offset2, HOST_WIDE_INT max_size2,

                           bool ref2_is_decl)

                           bool ref2_is_decl)

{

{

  /* If one reference is a component references through pointers try to find a

  /* If one reference is a component references through pointers try to find a

     common base and apply offset based disambiguation.  This handles

     common base and apply offset based disambiguation.  This handles

     for example

     for example

       struct A { int i; int j; } *q;

       struct A { int i; int j; } *q;

       struct B { struct A a; int k; } *p;

       struct B { struct A a; int k; } *p;

     disambiguating q->i and p->a.j.  */

     disambiguating q->i and p->a.j.  */

  tree *refp;

  tree *refp;

  int same_p;

  int same_p;

  /* Now search for the type1 in the access path of ref2.  This

  /* Now search for the type1 in the access path of ref2.  This

     would be a common base for doing offset based disambiguation on.  */

     would be a common base for doing offset based disambiguation on.  */

  refp = &ref2;

  refp = &ref2;

  while (handled_component_p (*refp)

  while (handled_component_p (*refp)

         && same_type_for_tbaa (TREE_TYPE (*refp), type1) == 0)

         && same_type_for_tbaa (TREE_TYPE (*refp), type1) == 0)

    refp = &TREE_OPERAND (*refp, 0);

    refp = &TREE_OPERAND (*refp, 0);

  same_p = same_type_for_tbaa (TREE_TYPE (*refp), type1);

  same_p = same_type_for_tbaa (TREE_TYPE (*refp), type1);

  /* If we couldn't compare types we have to bail out.  */

  /* If we couldn't compare types we have to bail out.  */