[x86] add test for pcmpeq with 0; NFC

Author: rotateright

llvm/test/CodeGen/X86/setcc-lowering.ll

@@ -103,3 +103,27 @@ for_loop599:                                      ; preds = %for_loop599, %for_t
 for_exit600:                                      ; preds = %for_loop599
   ret void
 }
+
+define <4 x i32> @pcmpgt(<4 x i8> %x) {
+; AVX-LABEL: pcmpgt:
+; AVX:       # %bb.0:
+; AVX-NEXT:    vpmovzxbd {{.*#+}} xmm0 = xmm0[0],zero,zero,zero,xmm0[1],zero,zero,zero,xmm0[2],zero,zero,zero,xmm0[3],zero,zero,zero
+; AVX-NEXT:    vpxor %xmm1, %xmm1, %xmm1
+; AVX-NEXT:    vpcmpeqd %xmm1, %xmm0, %xmm0
+; AVX-NEXT:    vpcmpeqd %xmm1, %xmm1, %xmm1
+; AVX-NEXT:    vpxor %xmm1, %xmm0, %xmm0
+; AVX-NEXT:    retq
+;
+; KNL-32-LABEL: pcmpgt:
+; KNL-32:       # %bb.0:
+; KNL-32-NEXT:    vpmovzxbd {{.*#+}} xmm0 = xmm0[0],zero,zero,zero,xmm0[1],zero,zero,zero,xmm0[2],zero,zero,zero,xmm0[3],zero,zero,zero
+; KNL-32-NEXT:    vpxor %xmm1, %xmm1, %xmm1
+; KNL-32-NEXT:    vpcmpeqd %xmm1, %xmm0, %xmm0
+; KNL-32-NEXT:    vpternlogq $15, %zmm0, %zmm0, %zmm0
+; KNL-32-NEXT:    # kill: def $xmm0 killed $xmm0 killed $zmm0
+; KNL-32-NEXT:    retl
+  %zext = zext <4 x i8> %x to <4 x i32>
+  %icmp = icmp ne <4 x i32> %zext, zeroinitializer
+  %sext = sext <4 x i1> %icmp to <4 x i32>
+  ret <4 x i32> %sext
+}