diff --git a/clang/lib/CodeGen/ItaniumCXXABI.cpp b/clang/lib/CodeGen/ItaniumCXXABI.cpp
--- a/clang/lib/CodeGen/ItaniumCXXABI.cpp
+++ b/clang/lib/CodeGen/ItaniumCXXABI.cpp
@@ -2339,10 +2339,16 @@
                                              QualType ElementType) {
   assert(requiresArrayCookie(expr));
 
-  CharUnits SizeSize = CGF.getSizeSize();
-  CharUnits CookieSize = getArrayCookieSizeImpl(ElementType);
   unsigned AS = NewPtr.getAddressSpace();
 
+  ASTContext &Ctx = getContext();
+  CharUnits SizeSize = CGF.getSizeSize();
+
+  // The size of the cookie.
+  CharUnits CookieSize =
+      std::max(SizeSize, Ctx.getPreferredTypeAlignInChars(ElementType));
+  assert(CookieSize == getArrayCookieSizeImpl(ElementType));
+
   // Compute an offset to the cookie.
   Address CookiePtr = NewPtr;
   CharUnits CookieOffset = CookieSize - SizeSize;
@@ -2418,19 +2424,11 @@
                                          QualType elementType) {
   assert(requiresArrayCookie(expr));
 
-  CharUnits sizeSize = CGF.getSizeSize();
-  CharUnits cookieSize = getArrayCookieSizeImpl(elementType);
   unsigned AS = newPtr.getAddressSpace();
 
   // The cookie is always at the start of the buffer.
   Address cookie = newPtr;
 
-  // Compute an offset to the cookie.
-  CharUnits cookieOffset = cookieSize - sizeSize*2;
-  assert(cookieOffset.isZero());
-  if (!cookieOffset.isZero())
-    cookie = CGF.Builder.CreateConstInBoundsByteGEP(cookie, cookieOffset);
-
   // The first element is the element size.
   cookie = CGF.Builder.CreateElementBitCast(cookie, CGF.SizeTy);
   llvm::Value *elementSize = llvm::ConstantInt::get(CGF.SizeTy,
@@ -2456,6 +2454,7 @@
 
   // Finally, compute a pointer to the actual data buffer by skipping
   // over the cookie completely.
+  CharUnits cookieSize = ARMCXXABI::getArrayCookieSizeImpl(elementType);
   return CGF.Builder.CreateConstInBoundsByteGEP(newPtr, cookieSize);
 }