Add test for the inverse case

Author: Poseydon42

llvm/test/Transforms/InstCombine/scmp.ll

@@ -358,6 +358,19 @@ define i8 @scmp_from_select_eq_and_gt(i32 %x, i32 %y) {
   ret i8 %r
 }
 
+define i8 @scmp_from_select_eq_and_gt_inverse(i32 %x, i32 %y) {
+; CHECK-LABEL: define i8 @scmp_from_select_eq_and_gt_inverse(
+; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
+; CHECK-NEXT:    [[R:%.*]] = call i8 @llvm.scmp.i8.i32(i32 [[X]], i32 [[Y]])
+; CHECK-NEXT:    ret i8 [[R]]
+;
+  %ne = icmp ne i32 %x, %y
+  %gt = icmp sgt i32 %x, %y
+  %sel1 = select i1 %gt, i8 1, i8 -1
+  %r = select i1 %ne, i8 %sel1, i8 0
+  ret i8 %r
+}
+
 define <4 x i8> @scmp_from_select_eq_and_gt_vec(<4 x i32> %x, <4 x i32> %y) {
 ; CHECK-LABEL: define <4 x i8> @scmp_from_select_eq_and_gt_vec(
 ; CHECK-SAME: <4 x i32> [[X:%.*]], <4 x i32> [[Y:%.*]]) {