On Sat, Jul 1, 2023 at 10:23 AM Andrew Pinski via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> This fixes the first part of this bug where `a ? -1 : 0`
> would cause a value of 1 into the signed boolean value.
> It fixes the problem by casting to an integer type of
> the same size/signedness before doing the negative and
> then casting to the type of expression.
>
> OK? Bootstrapped and tested on x86_64.
OK.
Richard.
> gcc/ChangeLog:
>
> * match.pd (a?-1:0): Cast type an integer type
> rather the type before the negative.
> (a?0:-1): Likewise.
> ---
> gcc/match.pd | 22 ++++++++++++++++++++--
> 1 file changed, 20 insertions(+), 2 deletions(-)
>
> diff --git a/gcc/match.pd b/gcc/match.pd
> index 45c72e733a5..a0d114f6a16 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -4703,7 +4703,12 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> /* a ? -1 : 0 -> -a. No need to check the TYPE_PRECISION not being 1
> here as the powerof2cst case above will handle that case correctly.
> */
> (if (INTEGRAL_TYPE_P (type) && integer_all_onesp (@1))
> - (negate (convert (convert:boolean_type_node @0))))))
> + (with {
> + auto prec = TYPE_PRECISION (type);
> + auto unsign = TYPE_UNSIGNED (type);
> + tree inttype = build_nonstandard_integer_type (prec, unsign);
> + }
> + (convert (negate (convert:inttype (convert:boolean_type_node @0))))))))
> (if (integer_zerop (@1))
> (with {
> tree booltrue = constant_boolean_node (true, boolean_type_node);
> @@ -4722,7 +4727,20 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> /* a ? -1 : 0 -> -(!a). No need to check the TYPE_PRECISION not being 1
> here as the powerof2cst case above will handle that case correctly.
> */
> (if (INTEGRAL_TYPE_P (type) && integer_all_onesp (@2))
> - (negate (convert (bit_xor (convert:boolean_type_node @0) { booltrue; }
> ))))
> + (with {
> + auto prec = TYPE_PRECISION (type);
> + auto unsign = TYPE_UNSIGNED (type);
> + tree inttype = build_nonstandard_integer_type (prec, unsign);
> + }
> + (convert
> + (negate
> + (convert:inttype
> + (bit_xor (convert:boolean_type_node @0) { booltrue; } )
> + )
> + )
> + )
> + )
> + )
> )
> )
> )
> --
> 2.31.1
>
