[Bug rtl-optimization/94838] New: Failure to optimize out useless zero-ing after register was already zero-ed

[gabravier at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94838

            Bug ID: 94838
           Summary: Failure to optimize out useless zero-ing after
                    register was already zero-ed
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

int f(bool b, int *p)
{
    return b && *p;
}

GCC generates this with -O3:

f(bool, int*):
  xor eax, eax
  test dil, dil
  je .L1
  mov edx, DWORD PTR [rsi]
  xor eax, eax ; This can be removed, since eax is already 0 here
  test edx, edx
  setne al
.L1:
  ret