[Bug target/91569] Optimisation test case and unnecessary XOR-OR pair instead of MOV.

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91569

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|                            |11.1.0

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
For test3 GCC 11+ produces:

opt_test3(int):
.LFB2:
        .cfi_startproc
        movslq  %edi, %rax
        movb    $4, %ah
        ret

Which is exactly what you should see.

Gimple level looks the same between GCC 10 and GCC 11:
  _1 = (long int) num_2(D);
  a = _1;
  MEM[(char *)&a + 1B] = 4;
  _6 = a;

I suspect a decl no longer has address taken so it is not going to the stack
right away.