1 files changed, 37 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/sub-xor.ll b/test/Transforms/InstCombine/sub-xor.ll
new file mode 100644
index 0000000..279e4ac
--- /dev/null
+++ b/test/Transforms/InstCombine/sub-xor.ll
@@ -0,0 +1,37 @@
+; RUN: opt -instcombine -S < %s | FileCheck %s
+
+define i32 @test1(i32 %x) nounwind {
+  %and = and i32 %x, 31
+  %sub = sub i32 63, %and
+  ret i32 %sub
+
+; CHECK: @test1
+; CHECK-NEXT: and i32 %x, 31
+; CHECK-NEXT: xor i32 %and, 63
+; CHECK-NEXT: ret
+}
+
+declare i32 @llvm.ctlz.i32(i32, i1) nounwind readnone
+
+define i32 @test2(i32 %x) nounwind {
+  %count = tail call i32 @llvm.ctlz.i32(i32 %x, i1 true) nounwind readnone
+  %sub = sub i32 31, %count
+  ret i32 %sub
+
+; CHECK: @test2
+; CHECK-NEXT: ctlz
+; CHECK-NEXT: xor i32 %count, 31
+; CHECK-NEXT: ret
+}
+
+define i32 @test3(i32 %x) nounwind {
+  %and = and i32 %x, 31
+  %sub = xor i32 31, %and
+  %add = add i32 %sub, 42
+  ret i32 %add
+
+; CHECK: @test3
+; CHECK-NEXT: and i32 %x, 31
+; CHECK-NEXT: sub i32 73, %and
+; CHECK-NEXT: ret
+}