diff --git a/llvm/test/Transforms/FunctionSpecialization/function-specialization.ll b/llvm/test/Transforms/FunctionSpecialization/function-specialization.ll
new file mode 100644
index 0000000..0606d5d
--- /dev/null
+++ b/llvm/test/Transforms/FunctionSpecialization/function-specialization.ll
@@ -0,0 +1,50 @@
+; RUN: opt -function-specialization -deadargelim -inline -S < %s | FileCheck %s
+
+; CHECK-LABEL: @main(i64 %x, i1 %flag) {
+; CHECK:         entry:
+; CHECK-NEXT:      br i1 %flag, label %plus, label %minus
+; CHECK:         plus:
+; CHECK-NEXT:      [[TMP0:%.+]] = add i64 %x, 1
+; CHECH-NEXT:      br label %merge
+; CHECK:         minus:
+; CHECK-NEXT:      [[TMP1:%.+]] = sub i64 %x, 1
+; CHECK-NEXT:      br label %merge
+; CHECK:         merge:
+; CHECK-NEXT:      [[TMP2:%.+]] = phi i64 [ [[TMP0]], %plus ], [ [[TMP1]], %minus ]
+; CHECK-NEXT:      ret i64 [[TMP2]]
+; CHECK-NEXT:  }
+;
+define i64 @main(i64 %x, i1 %flag) {
+entry:
+  br i1 %flag, label %plus, label %minus
+
+plus:
+  %tmp0 = call i64 @compute(i64 %x, i64 (i64)* @plus)
+  br label %merge
+
+minus:
+  %tmp1 = call i64 @compute(i64 %x, i64 (i64)* @minus)
+  br label %merge
+
+merge:
+  %tmp2 = phi i64 [ %tmp0, %plus ], [ %tmp1, %minus]
+  ret i64 %tmp2
+}
+
+define internal i64 @compute(i64 %x, i64 (i64)* %binop) {
+entry:
+  %tmp0 = call i64 %binop(i64 %x)
+  ret i64 %tmp0
+}
+
+define internal i64 @plus(i64 %x) {
+entry:
+  %tmp0 = add i64 %x, 1
+  ret i64 %tmp0
+}
+
+define internal i64 @minus(i64 %x) {
+entry:
+  %tmp0 = sub i64 %x, 1
+  ret i64 %tmp0
+}