diff --git a/clang/unittests/Basic/FixedPointTest.cpp b/clang/unittests/Basic/FixedPointTest.cpp
index 6d608f1faff2..74b676bb21ff 100644
--- a/clang/unittests/Basic/FixedPointTest.cpp
+++ b/clang/unittests/Basic/FixedPointTest.cpp
@@ -364,12 +364,19 @@ TEST(FixedPoint, compare) {
 void CheckUnsaturatedConversion(FixedPointSemantics Src,
                                 FixedPointSemantics Dst, int64_t TestVal) {
   int64_t ScaledVal = TestVal;
+  bool IsNegative = ScaledVal < 0;
+  if (IsNegative)
+    ScaledVal = -ScaledVal;
+
   if (Dst.getScale() > Src.getScale()) {
     ScaledVal <<= (Dst.getScale() - Src.getScale());
   } else {
     ScaledVal >>= (Src.getScale() - Dst.getScale());
   }
 
+  if (IsNegative)
+    ScaledVal = -ScaledVal;
+
   APFixedPoint Fixed(TestVal, Src);
   APFixedPoint Expected(ScaledVal, Dst);
   ASSERT_EQ(Fixed.convert(Dst), Expected);