[PATCH] Some PTA fixes

[Richard Guenther-3]

This fixes some issues in generic PTA code that I noticed when working on
IPA-PTA.

Bootstrapped and tested on x86_64-unknown-linux-gnu, applied to trunk.

Richard.

2009-11-07  Richard Guenther  <rguenther@...>

        * tree-ssa-structalias.c (build_succ_graph): Feed stores
        to anything only to variables that can take pointers.
        (get_constraint_for_ssa_var): Properly exclude full
        variables from expanding.
        (first_vi_for_offset): Avoid overflow in arithmetic.
        (first_or_preceding_vi_for_offset): Likewise.
        (count_num_arguments): Fix implementation.
        (gate_ipa_pta): Do not run when not optimizing.

Index: gcc/tree-ssa-structalias.c
===================================================================
*** gcc/tree-ssa-structalias.c (revision 153973)
--- gcc/tree-ssa-structalias.c (working copy)
*************** build_succ_graph (void)
*** 1269,1279 ****
  }
      }
 
!   /* Add edges from STOREDANYTHING to all non-direct nodes.  */
    t = find (storedanything_id);
    for (i = integer_id + 1; i < FIRST_REF_NODE; ++i)
      {
!       if (!TEST_BIT (graph->direct_nodes, i))
  add_graph_edge (graph, find (i), t);
      }
  }
--- 1269,1281 ----
  }
      }
 
!   /* Add edges from STOREDANYTHING to all non-direct nodes that can
!      receive pointers.  */
    t = find (storedanything_id);
    for (i = integer_id + 1; i < FIRST_REF_NODE; ++i)
      {
!       if (!TEST_BIT (graph->direct_nodes, i)
!  && get_varinfo (i)->may_have_pointers)
  add_graph_edge (graph, find (i), t);
      }
  }
*************** get_constraint_for_ssa_var (tree t, VEC(
*** 2720,2726 ****
 
    /* If we are not taking the address of the constraint expr, add all
       sub-fiels of the variable as well.  */
!   if (!address_p)
      {
        for (; vi; vi = vi->next)
  {
--- 2722,2729 ----
 
    /* If we are not taking the address of the constraint expr, add all
       sub-fiels of the variable as well.  */
!   if (!address_p
!       && !vi->is_full_var)
      {
        for (; vi; vi = vi->next)
  {
*************** first_vi_for_offset (varinfo_t start, un
*** 4032,4038 ****
  In that case, however, offset should still be within the size
  of the variable. */
        if (offset >= start->offset
!  && offset < (start->offset + start->size))
  return start;
 
        start= start->next;
--- 4035,4041 ----
  In that case, however, offset should still be within the size
  of the variable. */
        if (offset >= start->offset
!  && (offset - start->offset) < start->size)
  return start;
 
        start= start->next;
*************** first_or_preceding_vi_for_offset (varinf
*** 4062,4068 ****
       directly preceding offset which may be the last field.  */
    while (start->next
  && offset >= start->offset
! && !(offset < (start->offset + start->size)))
      start = start->next;
 
    return start;
--- 4065,4071 ----
       directly preceding offset which may be the last field.  */
    while (start->next
  && offset >= start->offset
! && !((offset - start->offset) < start->size))
      start = start->next;
 
    return start;
*************** push_fields_onto_fieldstack (tree type,
*** 4286,4306 ****
  static unsigned int
  count_num_arguments (tree decl, bool *is_varargs)
  {
!   unsigned int i = 0;
    tree t;
 
!   for (t = TYPE_ARG_TYPES (TREE_TYPE (decl));
!        t;
!        t = TREE_CHAIN (t))
!     {
!       if (TREE_VALUE (t) == void_type_node)
! break;
!       i++;
!     }
!
    if (!t)
      *is_varargs = true;
!   return i;
  }
 
  /* Creation function node for DECL, using NAME, and return the index
--- 4289,4310 ----
  static unsigned int
  count_num_arguments (tree decl, bool *is_varargs)
  {
!   unsigned int num = 0;
    tree t;
 
!   /* Capture named arguments for K&R functions.  They do not
!      have a prototype and thus no TYPE_ARG_TYPES.  */
!   for (t = DECL_ARGUMENTS (decl); t; t = TREE_CHAIN (t))
!     ++num;
!
!   /* Check if the function has variadic arguments.  */
!   for (t = TYPE_ARG_TYPES (TREE_TYPE (decl)); t; t = TREE_CHAIN (t))
!     if (TREE_VALUE (t) == void_type_node)
!       break;
    if (!t)
      *is_varargs = true;
!
!   return num;
  }
 
  /* Creation function node for DECL, using NAME, and return the index
*************** struct gimple_opt_pass pass_build_ealias
*** 5654,5660 ****
  static bool
  gate_ipa_pta (void)
  {
!   return (flag_ipa_pta
   /* Don't bother doing anything if the program has errors.  */
   && !(errorcount || sorrycount));
  }
--- 5658,5665 ----
  static bool
  gate_ipa_pta (void)
  {
!   return (optimize
!  && flag_ipa_pta
   /* Don't bother doing anything if the program has errors.  */
   && !(errorcount || sorrycount));
  }