diff --git a/llvm/lib/Target/AArch64/AArch64Subtarget.h b/llvm/lib/Target/AArch64/AArch64Subtarget.h
--- a/llvm/lib/Target/AArch64/AArch64Subtarget.h
+++ b/llvm/lib/Target/AArch64/AArch64Subtarget.h
@@ -209,9 +209,7 @@
   }
 
   unsigned getMaxInterleaveFactor() const { return MaxInterleaveFactor; }
-  unsigned getVectorInsertExtractBaseCost() const {
-    return VectorInsertExtractBaseCost;
-  }
+  unsigned getVectorInsertExtractBaseCost() const;
   unsigned getCacheLineSize() const override { return CacheLineSize; }
   unsigned getPrefetchDistance() const override { return PrefetchDistance; }
   unsigned getMinPrefetchStride(unsigned NumMemAccesses,
diff --git a/llvm/lib/Target/AArch64/AArch64Subtarget.cpp b/llvm/lib/Target/AArch64/AArch64Subtarget.cpp
--- a/llvm/lib/Target/AArch64/AArch64Subtarget.cpp
+++ b/llvm/lib/Target/AArch64/AArch64Subtarget.cpp
@@ -52,6 +52,15 @@
 static cl::opt<bool> UseAA("aarch64-use-aa", cl::init(true),
                            cl::desc("Enable the use of AA during codegen."));
 
+static cl::opt<int> VectorInsertExtractCostAdjustment(
+    "aarch64-insert-extract-cost-adjustment", cl::init(0),
+    cl::desc("Adjustment to base cost of vector insert/extract"), cl::Hidden);
+
+unsigned AArch64Subtarget::getVectorInsertExtractBaseCost() const {
+  return std::max(0, static_cast<int>(VectorInsertExtractBaseCost) +
+                         VectorInsertExtractCostAdjustment);
+}
+
 AArch64Subtarget &AArch64Subtarget::initializeSubtargetDependencies(
     StringRef FS, StringRef CPUString, StringRef TuneCPUString) {
   // Determine default and user-specified characteristics