On Tue, Jun 11, 2024 at 01:36:35PM +0800, liuhongt wrote:
> In theory, const_wide_int can also be handle with extra check for each
> components of the HOST_WIDE_INT array, and the check is need for both
> shift and bit_and operands.
> I assume the optimization opportnunity is rare, so the patch just add
> extra check to make sure GET_MODE_INNER (mode) can fix into a
> HOST_WIDE_INT.
I think if you only handle CONST_INT_P, you should check just for that, and
in both places where you check for CONST_VECTOR_DUPLICATE_P (there is one
spot 2 lines above this).
So add
&& CONST_INT_P (XVECEXP (XEXP (op0, 1), 0, 0))
and
&& CONST_INT_P (XVECEXP (op1, 0, 0))
tests right below those && CONST_VECTOR_DUPLICATE_P (something) tests.
>
> gcc/ChangeLog:
>
> PR target/115384
> * simplify-rtx.cc (simplify_context::simplify_binary_operation_1):
> Only do the simplification of (AND (ASHIFTRT A imm) mask)
> to (LSHIFTRT A imm) when inner mode fits HOST_WIDE_INT.
>
> gcc/testsuite/ChangeLog:
>
> * gcc.target/i386/pr115384.c: New test.
Jakub
