[VectorCombine] Add test coverage for #89390

Author: RKSimon

llvm/test/Transforms/VectorCombine/X86/shuffle-of-binops.ll

@@ -199,6 +199,23 @@ define <16 x i16> @shuf_and_v16i16_yy_expensive_shuf(<16 x i16> %x, <16 x i16> %
   %r = shufflevector <16 x i16> %b0, <16 x i16> %b1, <16 x i32> <i32 15, i32 22, i32 25, i32 13, i32 28, i32 0, i32 poison, i32 3, i32 0, i32 30, i32 3, i32 7, i32 9, i32 19, i32 2, i32 22>
   ret <16 x i16> %r
 }
+
+; TODO: negative test - don't fold shuffle(divrem(x,y),divrem(z,w)) if mask contains poison (PR89390)
+
+define <4 x i32> @shuf_srem_v4i32_poison(<4 x i32> %a0, <4 x i32> %a1) {
+; CHECK-LABEL: define <4 x i32> @shuf_srem_v4i32_poison(
+; CHECK-SAME: <4 x i32> [[A0:%.*]], <4 x i32> [[A1:%.*]]) #[[ATTR0]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = shufflevector <4 x i32> [[A1]], <4 x i32> <i32 1, i32 1, i32 1, i32 1>, <4 x i32> <i32 0, i32 poison, i32 6, i32 3>
+; CHECK-NEXT:    [[TMP2:%.*]] = shufflevector <4 x i32> [[A0]], <4 x i32> poison, <4 x i32> <i32 0, i32 poison, i32 2, i32 3>
+; CHECK-NEXT:    [[R:%.*]] = srem <4 x i32> [[TMP1]], [[TMP2]]
+; CHECK-NEXT:    ret <4 x i32> [[R]]
+;
+  %srem0 = srem <4 x i32> %a1, %a0
+  %srem1 = srem <4 x i32> <i32 1, i32 1, i32 1, i32 1>, %a0
+  %r = shufflevector <4 x i32> %srem0, <4 x i32> %srem1, <4 x i32> <i32 0, i32 poison, i32 6, i32 3>
+  ret <4 x i32> %r
+}
+
 ;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
 ; AVX: {{.*}}
 ; SSE: {{.*}}