[Bug target/95756] New: Failure to optimize memory operations with _Complex

[gabravier at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95756

            Bug ID: 95756
           Summary: Failure to optimize memory operations with _Complex
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

float _Complex f()
{
    return {0, 0};
}

With -O3, LLVM outputs this :

f(): # @f()
  xorps xmm0, xmm0
  ret

GCC outputs this :

f():
  mov DWORD PTR [rsp-8], 0x00000000
  mov DWORD PTR [rsp-4], 0x00000000
  movq xmm0, QWORD PTR [rsp-8]
  ret