diff --git a/lib/Target/ARM64/ARM64TargetTransformInfo.cpp b/lib/Target/ARM64/ARM64TargetTransformInfo.cpp
index 8a6253d7681..5323b8965f4 100644
--- a/lib/Target/ARM64/ARM64TargetTransformInfo.cpp
+++ b/lib/Target/ARM64/ARM64TargetTransformInfo.cpp
@@ -166,7 +166,7 @@ unsigned ARM64TTI::getIntImmCost(const APInt &Imm, Type *Ty) const {
   // chunk.
   unsigned Cost = 0;
   for (unsigned ShiftVal = 0; ShiftVal < BitSize; ShiftVal += 64) {
-    APInt Tmp = ImmVal.ashr(ShiftVal).getLoBits(64);
+    APInt Tmp = ImmVal.ashr(ShiftVal).sextOrTrunc(64);
     int64_t Val = Tmp.getSExtValue();
     Cost += getIntImmCost(Val);
   }
diff --git a/test/Transforms/ConstantHoisting/ARM64/large-immediate.ll b/test/Transforms/ConstantHoisting/ARM64/large-immediate.ll
new file mode 100644
index 00000000000..0965a45ea6e
--- /dev/null
+++ b/test/Transforms/ConstantHoisting/ARM64/large-immediate.ll
@@ -0,0 +1,10 @@
+; RUN: opt -mtriple=arm64-darwin-unknown -S -consthoist < %s | FileCheck %s
+
+define i128 @test1(i128 %a) nounwind {
+; CHECK-LABEL: test1
+; CHECK: %const = bitcast i128 12297829382473034410122878 to i128
+  %1 = add i128 %a, 12297829382473034410122878
+  %2 = add i128 %1, 12297829382473034410122878
+  ret i128 %2
+}
+