[Bug tree-optimization/103317] Spec 2017 benchmark blender_r fails with -Ofast on PowerPc (power9, power10)

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103317

Peter Bergner <bergner at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2021-11-18
           Keywords|                            |ice-on-valid-code

--- Comment #2 from Peter Bergner <bergner at gcc dot gnu.org> ---
Confirmed.  Here's a creduced test case. This fails even with -O1 -mcpu=power8:

bergner@pike:~/gcc/BUGS/PR103317$ cat bug.i
int a, b;
char c;
void
d (void)
{
  char e = c;
  if (b)
    if (c < 16 - 11)
      e = 16 - 11;
  if (e > 8)
    e = 8;
  a = e;
}

bergner@pike:~/gcc/BUGS/PR103317$ gcc -S -O1 -mcpu=power8 bug.i 
bug.i: In function ‘d’:
bug.i:13:1: error: definition in block 3 does not dominate use in block 2
   13 | }
      | ^
for SSA_NAME: _2 in statement:
e_5 = PHI <_2(2), _4(3)>
PHI argument
_2
for PHI node
e_5 = PHI <_2(2), _4(3)>
during GIMPLE pass: phiopt
bug.i:13:1: internal compiler error: verify_ssa failed
0x11989b73 verify_ssa(bool, bool)