[InstCombine] Add pre-commit tests. NFC.

Author: dtcxzyw

llvm/test/Transforms/InstCombine/icmp.ll

@@ -815,6 +815,53 @@ define i1 @test46(i32 %X, i32 %Y, i32 %Z) {
   ret i1 %C
 }
 
+define i1 @test46_multiuse1(i32 %X, i32 %Y, i32 %Z) {
+; CHECK-LABEL: @test46_multiuse1(
+; CHECK-NEXT:    [[A:%.*]] = ashr exact i32 [[X:%.*]], [[Z:%.*]]
+; CHECK-NEXT:    call void @use_i32(i32 [[A]])
+; CHECK-NEXT:    [[B:%.*]] = ashr exact i32 [[Y:%.*]], [[Z]]
+; CHECK-NEXT:    [[C:%.*]] = icmp ult i32 [[A]], [[B]]
+; CHECK-NEXT:    ret i1 [[C]]
+;
+  %A = ashr exact i32 %X, %Z
+  call void @use_i32(i32 %A)
+  %B = ashr exact i32 %Y, %Z
+  %C = icmp ult i32 %A, %B
+  ret i1 %C
+}
+
+define i1 @test46_multiuse2(i32 %X, i32 %Y, i32 %Z) {
+; CHECK-LABEL: @test46_multiuse2(
+; CHECK-NEXT:    [[A:%.*]] = ashr exact i32 [[X:%.*]], [[Z:%.*]]
+; CHECK-NEXT:    [[B:%.*]] = ashr exact i32 [[Y:%.*]], [[Z]]
+; CHECK-NEXT:    call void @use_i32(i32 [[B]])
+; CHECK-NEXT:    [[C:%.*]] = icmp ult i32 [[A]], [[B]]
+; CHECK-NEXT:    ret i1 [[C]]
+;
+  %A = ashr exact i32 %X, %Z
+  %B = ashr exact i32 %Y, %Z
+  call void @use_i32(i32 %B)
+  %C = icmp ult i32 %A, %B
+  ret i1 %C
+}
+
+define i1 @test46_multiuse3(i32 %X, i32 %Y, i32 %Z) {
+; CHECK-LABEL: @test46_multiuse3(
+; CHECK-NEXT:    [[A:%.*]] = ashr exact i32 [[X:%.*]], [[Z:%.*]]
+; CHECK-NEXT:    call void @use_i32(i32 [[A]])
+; CHECK-NEXT:    [[B:%.*]] = ashr exact i32 [[Y:%.*]], [[Z]]
+; CHECK-NEXT:    call void @use_i32(i32 [[B]])
+; CHECK-NEXT:    [[C:%.*]] = icmp ult i32 [[A]], [[B]]
+; CHECK-NEXT:    ret i1 [[C]]
+;
+  %A = ashr exact i32 %X, %Z
+  call void @use_i32(i32 %A)
+  %B = ashr exact i32 %Y, %Z
+  call void @use_i32(i32 %B)
+  %C = icmp ult i32 %A, %B
+  ret i1 %C
+}
+
 ; PR9343 #5
 define i1 @test47(i32 %X, i32 %Y, i32 %Z) {
 ; CHECK-LABEL: @test47(