On Tue, Jul 15, 2025 at 12:18 PM Andrew Pinski <quic_apin...@quicinc.com> wrote:
>
> The switch conversion code asks initializer_constant_valid_p
> if the expression is a valid initializer constant and for
> vector types which have a non-constant elements initializer_constant_valid_p
> would return it is valid. But it should be rejected as not being
> valid for an initializer.
>
> Build and tested for aarch64-linux-gnu.
Whoops I didn't see a regression until now. This actually regresses PR
116595. So I have to hold back on this for now.
I will debug and figure out how to solve both at the same time.
initializer_constant_valid_p should be rejecting it but at the same
time something else needs to change in the front-end I think.
Thanks,
Andrew Pinski
>
> PR tree-optimization/121091
>
> gcc/ChangeLog:
>
> * varasm.cc (initializer_constant_valid_p_1): Reject vector types
> which
> have a non-constant number of elements.
>
> gcc/testsuite/ChangeLog:
>
> * gcc.target/aarch64/sve/pr121091-1.c: New test.
>
> Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com>
> ---
> .../gcc.target/aarch64/sve/pr121091-1.c | 25 +++++++++++++++++++
> gcc/varasm.cc | 5 ++++
> 2 files changed, 30 insertions(+)
> create mode 100644 gcc/testsuite/gcc.target/aarch64/sve/pr121091-1.c
>
> diff --git a/gcc/testsuite/gcc.target/aarch64/sve/pr121091-1.c
> b/gcc/testsuite/gcc.target/aarch64/sve/pr121091-1.c
> new file mode 100644
> index 00000000000..ea2e5ce6b6a
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/sve/pr121091-1.c
> @@ -0,0 +1,25 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2" } */
> +
> +/* PR tree-optimization/121091 */
> +/* Switch conversion would convert this
> + into static constant array but since
> + svbool_t is a VLA type, it can't be
> + stored in a constant pool. */
> +
> +#include "arm_sve.h"
> +
> +svbool_t e(int mode, svbool_t pg) {
> + switch (mode) {
> + case 0:
> + pg = svptrue_pat_b16(SV_VL6);
> + break;
> + case 1:
> + pg = svpfalse_b();
> + break;
> + case 2:
> + pg = svptrue_pat_b16(SV_VL2);
> + break;
> + }
> + return pg;
> +}
> diff --git a/gcc/varasm.cc b/gcc/varasm.cc
> index 10c1d2e3137..36b7cd8812d 100644
> --- a/gcc/varasm.cc
> +++ b/gcc/varasm.cc
> @@ -5001,6 +5001,11 @@ initializer_constant_valid_p_1 (tree value, tree
> endtype, tree *cache)
> {
> tree ret;
>
> + /* Variable sized vectors are never valid for initializers. */
> + if (VECTOR_TYPE_P (endtype)
> + && !TYPE_VECTOR_SUBPARTS (endtype).is_constant ())
> + return NULL_TREE;
> +
> switch (TREE_CODE (value))
> {
> case CONSTRUCTOR:
> --
> 2.43.0
>
