On Tue, Mar 29, 2011 at 5:53 PM, Jakub Jelinek wrote:
> Hi!
>
> I've left these 4 out because I thought they should be fine given
> that the other operands are equal. But the testcase shows I was wrong.
>
> Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok
> for trunk?
Ok.
Thanks,
Richard.
> 2011-03-29 Jakub Jelinek
>
> PR c/48305
> * fold-const.c (fold_binary_loc) : Make sure
> arg10/arg11 in (X ^ Y) == (Z ^ W) are always fold converted to
> matching arg00/arg01 types.
>
> * gcc.c-torture/compile/pr48305.c: New test.
>
> --- gcc/fold-const.c.jj 2011-03-25 07:56:32.0 +0100
> +++ gcc/fold-const.c 2011-03-28 12:45:58.0 +0200
> @@ -12625,13 +12625,21 @@ fold_binary_loc (location_t loc,
> operand_equal_p guarantees no side-effects so we don't need
> to use omit_one_operand on Z. */
> if (operand_equal_p (arg01, arg11, 0))
> - return fold_build2_loc (loc, code, type, arg00, arg10);
> + return fold_build2_loc (loc, code, type, arg00,
> + fold_convert_loc (loc, TREE_TYPE (arg00),
> + arg10));
> if (operand_equal_p (arg01, arg10, 0))
> - return fold_build2_loc (loc, code, type, arg00, arg11);
> + return fold_build2_loc (loc, code, type, arg00,
> + fold_convert_loc (loc, TREE_TYPE (arg00),
> + arg11));
> if (operand_equal_p (arg00, arg11, 0))
> - return fold_build2_loc (loc, code, type, arg01, arg10);
> + return fold_build2_loc (loc, code, type, arg01,
> + fold_convert_loc (loc, TREE_TYPE (arg01),
> + arg10));
> if (operand_equal_p (arg00, arg10, 0))
> - return fold_build2_loc (loc, code, type, arg01, arg11);
> + return fold_build2_loc (loc, code, type, arg01,
> + fold_convert_loc (loc, TREE_TYPE (arg01),
> + arg11));
>
> /* Optimize (X ^ C1) op (Y ^ C2) as (X ^ (C1 ^ C2)) op Y. */
> if (TREE_CODE (arg01) == INTEGER_CST
> --- gcc/testsuite/gcc.c-torture/compile/pr48305.c.jj 2011-03-28
> 12:48:02.0 +0200
> +++ gcc/testsuite/gcc.c-torture/compile/pr48305.c 2011-03-28
> 12:47:49.0 +0200
> @@ -0,0 +1,7 @@
> +/* PR c/48305 */
> +
> +int
> +foo (int x)
> +{
> + return (x ^ 1) == (x ^ 1U);
> +}
>
> Jakub
>