[Bug middle-end/116259] New: __builtin_assoc_barrier with VLA type ICEs

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116259

            Bug ID: 116259
           Summary: __builtin_assoc_barrier with VLA type ICEs
           Product: gcc
           Version: 15.0
            Status: UNCONFIRMED
          Keywords: aarch64-sve, ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---
            Target: aarch64

Take this SVE code (-march=armv9-a):
```
#include <arm_sve.h>

#if 1
#define h(a) __builtin_assoc_barrier((a))
#else
#define h(a) (a)
#endif

svfloat64_t f( svfloat64_t  x)
{
  return h(x);
}

```

This ICEs with:
during GIMPLE pass: veclower2
<source>: In function 'svfloat64_t f(svfloat64_t)':
<source>:10:13: internal compiler error: in to_constant, at poly-int.h:588
   10 | svfloat64_t f( svfloat64_t  x)
      |             ^
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
See <https://gcc.gnu.org/bugs/> for instructions.