diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -2679,10 +2679,6 @@
    given the default specifications above, the i7 type will use the
    alignment of i8 (next largest) while both i65 and i256 will use the
    alignment of i64 (largest specified).
-#. If no match is found, and the type sought is a vector type, then the
-   largest vector type that is smaller than the sought vector type will
-   be used as a fall back. This happens because <128 x double> can be
-   implemented in terms of 64 <2 x double>, for example.
 
 The function of the data layout string may not be what you expect.
 Notably, this is not a specification from the frontend of what alignment
diff --git a/llvm/unittests/IR/DataLayoutTest.cpp b/llvm/unittests/IR/DataLayoutTest.cpp
--- a/llvm/unittests/IR/DataLayoutTest.cpp
+++ b/llvm/unittests/IR/DataLayoutTest.cpp
@@ -11,6 +11,7 @@
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/Type.h"
+#include "llvm/Testing/Support/Error.h"
 #include "gtest/gtest.h"
 
 using namespace llvm;
@@ -89,4 +90,20 @@
   EXPECT_EQ(ExplicitGlobal2->getAddressSpace(), 123u);
 }
 
+TEST(DataLayoutTest, VectorAlign) {
+  auto DL = DataLayout::parse("v128:128");
+  EXPECT_THAT_ERROR(DL.takeError(), Succeeded());
+
+  LLVMContext Context;
+  Type *const DoubleTy = Type::getDoubleTy(Context);
+  Type *const V128F64Ty = FixedVectorType::get(DoubleTy, 128);
+
+  // The alignment for a vector type larger than any specified vector type uses
+  // the natual alignment as a fallback. This is contrary to old LangRef
+  // documentation which claimed it would use the largest vector type smaller
+  // than the one sought after. In this case, it would have been Align(16).
+  EXPECT_EQ(Align(128 * 8), DL->getABITypeAlign(V128F64Ty));
+  EXPECT_EQ(Align(128 * 8), DL->getPrefTypeAlign(V128F64Ty));
+}
+
 } // anonymous namespace