On Fri, May 17, 2013 at 02:46:56PM +0200, Richard Biener wrote:
>
> stmt_kills_ref_p_1 wants to compare MEM_REF offset but compares
> the pointers instead (which are previously compared as equal).
> This breaks my fix for PR57303.
>
> Fixed thus, applied as obvious.
>
> Richard.
>
> 2013-05-17 Richard Biener <[email protected]>
>
> * tree-ssa-alias.c (stmt_kills_ref_p_1): Properly compare
> MEM_REF offsets.
Ugh, thanks.
As the 0th operand was equal, tree_int_cst_equal used to return always
1 and thus the if condition was never true.
> --- gcc/tree-ssa-alias.c (revision 199004)
> +++ gcc/tree-ssa-alias.c (working copy)
> @@ -2002,8 +2002,8 @@ stmt_kills_ref_p_1 (gimple stmt, ao_ref
> if (TREE_CODE (base) == MEM_REF && TREE_CODE (ref->base) == MEM_REF
> && TREE_OPERAND (base, 0) == TREE_OPERAND (ref->base, 0))
> {
> - if (!tree_int_cst_equal (TREE_OPERAND (base, 0),
> - TREE_OPERAND (ref->base, 0)))
> + if (!tree_int_cst_equal (TREE_OPERAND (base, 1),
> + TREE_OPERAND (ref->base, 1)))
> {
> double_int off1 = mem_ref_offset (base);
> off1 = off1.lshift (BITS_PER_UNIT == 8
Jakub
