[Bug target/100711] New: Miss optimization for pandn

[crazylht at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100711

            Bug ID: 100711
           Summary: Miss optimization for pandn
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: crazylht at gmail dot com
                CC: hjl.tools at gmail dot com
  Target Milestone: ---
            Target: x86_64-*-* i?86-*-*

cat test.c

typedef int v4si __attribute__((vector_size (16)));
v4si
foo (int a, v4si b)
{
    return (__extension__ (v4si) {~a, ~a, ~a, ~a}) & b;
}

generate

        notl    %edi
        vmovdqa %xmm0, %xmm1
        vpbroadcastd    %edi, %xmm0
        vpand   %xmm1, %xmm0, %xmm0
        ret

it should be better as

        vmovdqa %xmm0, %xmm1
        vpbroadcastd    %edi, %xmm0
        vpandn   %xmm1, %xmm0, %xmm0