File pr36765.diff of Package gcc43

2008-07-11  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/36765
	* tree-ssa-alias.c (compute_flow_insensitive_aliasing): Add
	aliases from HEAP vars to SMTs.

	* gcc.c-torture/execute/pr36765.c: New testcase.

Index: gcc/tree-ssa-alias.c
===================================================================
*** gcc/tree-ssa-alias.c	(revision 137712)
--- gcc/tree-ssa-alias.c	(working copy)
*************** have_common_aliases_p (bitmap tag1aliase
*** 2370,2375 ****
--- 2370,2377 ----
  static void
  compute_flow_insensitive_aliasing (struct alias_info *ai)
  {
+   referenced_var_iterator rvi;
+   tree var;
    size_t i;
  
    timevar_push (TV_FLOW_INSENSITIVE);
*************** compute_flow_insensitive_aliasing (struc
*** 2460,2465 ****
--- 2462,2485 ----
  	  add_may_alias (tag1, tag2);
  	}
      }
+ 
+   /* We have to add all HEAP variables to all SMTs aliases bitmaps.
+      As we don't know which effective type the HEAP will have we cannot
+      do better here and we need the conflicts with obfuscated pointers
+      (a simple (*(int[n] *)ptr)[i] will do, with ptr from a VLA array
+      allocation).  */
+   for (i = 0; i < ai->num_pointers; i++)
+     {
+       struct alias_map_d *p_map = ai->pointers[i];
+       tree tag = symbol_mem_tag (p_map->var);
+ 
+       FOR_EACH_REFERENCED_VAR (var, rvi)
+ 	{
+ 	  if (var_ann (var)->is_heapvar)
+ 	    add_may_alias (tag, var);
+ 	}
+     }
+ 
    timevar_pop (TV_FLOW_INSENSITIVE);
  }
  
Index: gcc/testsuite/gcc.c-torture/execute/pr36765.c
===================================================================
*** gcc/testsuite/gcc.c-torture/execute/pr36765.c	(revision 0)
--- gcc/testsuite/gcc.c-torture/execute/pr36765.c	(revision 0)
***************
*** 0 ****
--- 1,15 ----
+ int __attribute__((noinline))
+ foo(int i)
+ {
+   int *p = __builtin_malloc (4 * sizeof(int));
+   *p = 0;
+   p[i] = 1;
+   return *p;
+ }
+ extern void abort (void);
+ int main()
+ {
+   if (foo(0) != 1)
+     abort ();
+   return 0;
+ }