Index: llvm/trunk/include/llvm/Support/Alignment.h
===================================================================
--- llvm/trunk/include/llvm/Support/Alignment.h
+++ llvm/trunk/include/llvm/Support/Alignment.h
@@ -333,6 +333,14 @@
   return Lhs ? Lhs.getValue() / Divisor : MaybeAlign();
 }
 
+inline Align max(MaybeAlign Lhs, Align Rhs) {
+  return Lhs && *Lhs > Rhs ? *Lhs : Rhs;
+}
+
+inline Align max(Align Lhs, MaybeAlign Rhs) {
+  return Rhs && *Rhs > Lhs ? *Rhs : Lhs;
+}
+
 #undef ALIGN_CHECK_ISPOSITIVE
 #undef ALIGN_CHECK_ISSET
 
Index: llvm/trunk/unittests/Support/AlignmentTest.cpp
===================================================================
--- llvm/trunk/unittests/Support/AlignmentTest.cpp
+++ llvm/trunk/unittests/Support/AlignmentTest.cpp
@@ -227,6 +227,29 @@
   }
 }
 
+TEST(AlignmentTest, Max) {
+  // We introduce std::max here to test ADL.
+  using std::max;
+
+  // Uses llvm::max.
+  EXPECT_EQ(max(MaybeAlign(), Align(2)), Align(2));
+  EXPECT_EQ(max(Align(2), MaybeAlign()), Align(2));
+
+  EXPECT_EQ(max(MaybeAlign(1), Align(2)), Align(2));
+  EXPECT_EQ(max(Align(2), MaybeAlign(1)), Align(2));
+
+  EXPECT_EQ(max(MaybeAlign(2), Align(2)), Align(2));
+  EXPECT_EQ(max(Align(2), MaybeAlign(2)), Align(2));
+
+  EXPECT_EQ(max(MaybeAlign(4), Align(2)), Align(4));
+  EXPECT_EQ(max(Align(2), MaybeAlign(4)), Align(4));
+
+  // Uses std::max.
+  EXPECT_EQ(max(Align(2), Align(4)), Align(4));
+  EXPECT_EQ(max(MaybeAlign(2), MaybeAlign(4)), MaybeAlign(4));
+  EXPECT_EQ(max(MaybeAlign(), MaybeAlign()), MaybeAlign());
+}
+
 TEST(AlignmentTest, AssumeAligned) {
   EXPECT_EQ(assumeAligned(0), Align(1));
   EXPECT_EQ(assumeAligned(0), Align());