Re: [PATCH] Fix may_propagate_copy for pointers

[Andrew Pinski <pinskia at physics dot uc dot edu>]

On Sep 14, 2004, at 5:24 PM, Diego Novillo wrote:

> On Tue, 2004-09-14 at 19:55, Andrew Pinski wrote:
>
> > 	* tree-ssa-copy.c (may_propagate_copy): Don't check the aliasing
> > 	sets of the pointers but the aliasing sets of what they point to.
> OK after you add a test case that exposes the problem.

Testcase:
g++.dg/tree-ssa/pointer-reference-alias.C:

/* { dg-do compile } */
/* { dg-options "-O1 -fdump-tree-vars" } */

int f(int *a)
{
  int &b = *a;
  b = 0;
  return *a;
}

/* There should be only one dereferencing of a. */
/* { dg-final { scan-tree-dump-times "\\*a" 1 "vars"} } */


Thanks,
Andrew Pinski