[Bug target/94871] New: Failure to convert cmpeqpd+pxor with -1 into cmpneqpd

[gabravier at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94871

            Bug ID: 94871
           Summary: Failure to convert cmpeqpd+pxor with -1 into cmpneqpd
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

typedef double v2df __attribute__((vector_size(16)));
typedef int64_t v2di __attribute__((vector_size(16)));
typedef int8_t v16qi __attribute__((vector_size(16)));

inline v2di set1_epi8(int8_t a)
{
    return (v2di)(v16qi){a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a};
}

v2di cmpneq_pd(v2df a, v2df b)
{
    return ((v2di)__builtin_ia32_cmpeqpd(a, b) ^ set1_epi8(0xFF));
}

With -O3, LLVM outputs : 

cmpneq_pd(double __vector(2), double __vector(2)):
  cmpneqpd xmm0, xmm1
  ret

GCC outputs :

cmpneq_pd(double __vector(2), double __vector(2)):
  cmpeqpd xmm0, xmm1
  pcmpeqd xmm1, xmm1
  pxor xmm0, xmm1
  ret