[Bug rtl-optimization/112380] [14 regression] ICE when building mesa

[sjames at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112380

--- Comment #2 from Sam James <sjames at gcc dot gnu.org> ---
reduced:

```
enum { TGSI_FILE_NULL };
struct ureg_src {
  unsigned File : 4;
  unsigned : 2;
  unsigned : 2;
  unsigned : 2;
  unsigned : 1;
  unsigned IndirectFile : 4;
  unsigned IndirectSwizzle : 2;
  int : 16;
  int : 6;
  int : 16;
  int : 16;
  unsigned : 10;
} __trans_tmp_1;

int ureg_src_indirect_addr_1, ntt_emit_texture_instr_sampler_handle_src;

void ureg_scalar(struct ureg_src);

void ntt_emit_texture_instr() {
  struct ureg_src sampler;
  if (ntt_emit_texture_instr_sampler_handle_src)
    sampler = __trans_tmp_1;
  struct ureg_src reg = sampler;
  reg.File != TGSI_FILE_NULL;
  reg.IndirectFile = reg.IndirectSwizzle = ureg_src_indirect_addr_1;
  sampler = reg;
  ureg_scalar(reg);
}
```