LGTM
On Wed, May 25, 2022 at 5:48 AM Philipp Tomsich
<philipp.toms...@vrull.eu> wrote:
>
> Provide an easy way to constrain for constants that are a a single,
> consecutive run of ones.
>
> gcc/ChangeLog:
>
> * config/riscv/predicates.md (consecutive_bits_operand):
> Implement new predicate.
>
> Signed-off-by: Philipp Tomsich <philipp.toms...@vrull.eu>
> ---
>
> gcc/config/riscv/predicates.md | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/gcc/config/riscv/predicates.md b/gcc/config/riscv/predicates.md
> index c37caa2502b..90db5dfcdd5 100644
> --- a/gcc/config/riscv/predicates.md
> +++ b/gcc/config/riscv/predicates.md
> @@ -243,3 +243,14 @@ (define_predicate "const63_operand"
> (define_predicate "imm5_operand"
> (and (match_code "const_int")
> (match_test "INTVAL (op) < 5")))
> +
> +;; A CONST_INT operand that consists of a single run of consecutive set bits.
> +(define_predicate "consecutive_bits_operand"
> + (match_code "const_int")
> +{
> + unsigned HOST_WIDE_INT val = UINTVAL (op);
> + if (exact_log2 ((val >> ctz_hwi (val)) + 1) < 0)
> + return false;
> +
> + return true;
> +})
> --
> 2.34.1
>
