Merge "Update aosp/master LLVM for rebase to r230699."

1 files changed, 1753 insertions, 20 deletions

diff --git a/unittests/IR/MetadataTest.cpp b/unittests/IR/MetadataTest.cpp
index 4f7bd72..6f2372d 100644
--- a/unittests/IR/MetadataTest.cpp
+++ b/unittests/IR/MetadataTest.cpp
@@ -1,4 +1,4 @@
-//===- llvm/unittest/IR/Metadata.cpp - Metadata unit tests ----------------===//
+//===- unittests/IR/MetadataTest.cpp - Metadata unit tests ----------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -7,22 +7,67 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/IR/Metadata.h"
+#include "llvm/ADT/STLExtras.h"
 #include "llvm/IR/Constants.h"
+#include "llvm/IR/DebugInfoMetadata.h"
+#include "llvm/IR/Function.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Metadata.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/Type.h"
-#include "llvm/IR/ValueHandle.h"
 #include "llvm/Support/raw_ostream.h"
 #include "gtest/gtest.h"
 using namespace llvm;
 
 namespace {
 
+TEST(ContextAndReplaceableUsesTest, FromContext) {
+  LLVMContext Context;
+  ContextAndReplaceableUses CRU(Context);
+  EXPECT_EQ(&Context, &CRU.getContext());
+  EXPECT_FALSE(CRU.hasReplaceableUses());
+  EXPECT_FALSE(CRU.getReplaceableUses());
+}
+
+TEST(ContextAndReplaceableUsesTest, FromReplaceableUses) {
+  LLVMContext Context;
+  ContextAndReplaceableUses CRU(make_unique<ReplaceableMetadataImpl>(Context));
+  EXPECT_EQ(&Context, &CRU.getContext());
+  EXPECT_TRUE(CRU.hasReplaceableUses());
+  EXPECT_TRUE(CRU.getReplaceableUses());
+}
+
+TEST(ContextAndReplaceableUsesTest, makeReplaceable) {
+  LLVMContext Context;
+  ContextAndReplaceableUses CRU(Context);
+  CRU.makeReplaceable(make_unique<ReplaceableMetadataImpl>(Context));
+  EXPECT_EQ(&Context, &CRU.getContext());
+  EXPECT_TRUE(CRU.hasReplaceableUses());
+  EXPECT_TRUE(CRU.getReplaceableUses());
+}
+
+TEST(ContextAndReplaceableUsesTest, takeReplaceableUses) {
+  LLVMContext Context;
+  auto ReplaceableUses = make_unique<ReplaceableMetadataImpl>(Context);
+  auto *Ptr = ReplaceableUses.get();
+  ContextAndReplaceableUses CRU(std::move(ReplaceableUses));
+  ReplaceableUses = CRU.takeReplaceableUses();
+  EXPECT_EQ(&Context, &CRU.getContext());
+  EXPECT_FALSE(CRU.hasReplaceableUses());
+  EXPECT_FALSE(CRU.getReplaceableUses());
+  EXPECT_EQ(Ptr, ReplaceableUses.get());
+}
+
 class MetadataTest : public testing::Test {
 protected:
   LLVMContext Context;
+  MDNode *getNode() { return MDNode::get(Context, None); }
+  MDNode *getNode(Metadata *MD) { return MDNode::get(Context, MD); }
+  MDNode *getNode(Metadata *MD1, Metadata *MD2) {
+    Metadata *MDs[] = {MD1, MD2};
+    return MDNode::get(Context, MDs);
+  }
 };
 typedef MetadataTest MDStringTest;
 
@@ -58,7 +103,7 @@ TEST_F(MDStringTest, PrintingSimple) {
   std::string Str;
   raw_string_ostream oss(Str);
   s->print(oss);
-  EXPECT_STREQ("metadata !\"testing 1 2 3\"", oss.str().c_str());
+  EXPECT_STREQ("!\"testing 1 2 3\"", oss.str().c_str());
 }
 
 // Test printing of MDString with non-printable characters.
@@ -68,7 +113,7 @@ TEST_F(MDStringTest, PrintingComplex) {
   std::string Str;
   raw_string_ostream oss(Str);
   s->print(oss);
-  EXPECT_STREQ("metadata !\"\\00\\0A\\22\\5C\\FF\"", oss.str().c_str());
+  EXPECT_STREQ("!\"\\00\\0A\\22\\5C\\FF\"", oss.str().c_str());
 }
 
 typedef MetadataTest MDNodeTest;
@@ -80,30 +125,27 @@ TEST_F(MDNodeTest, Simple) {
 
   MDString *s1 = MDString::get(Context, StringRef(&x[0], 3));
   MDString *s2 = MDString::get(Context, StringRef(&y[0], 3));
-  ConstantInt *CI = ConstantInt::get(getGlobalContext(), APInt(8, 0));
+  ConstantAsMetadata *CI = ConstantAsMetadata::get(
+      ConstantInt::get(getGlobalContext(), APInt(8, 0)));
 
-  std::vector<Value *> V;
+  std::vector<Metadata *> V;
   V.push_back(s1);
   V.push_back(CI);
   V.push_back(s2);
 
   MDNode *n1 = MDNode::get(Context, V);
-  Value *const c1 = n1;
+  Metadata *const c1 = n1;
   MDNode *n2 = MDNode::get(Context, c1);
-  Value *const c2 = n2;
+  Metadata *const c2 = n2;
   MDNode *n3 = MDNode::get(Context, V);
   MDNode *n4 = MDNode::getIfExists(Context, V);
   MDNode *n5 = MDNode::getIfExists(Context, c1);
   MDNode *n6 = MDNode::getIfExists(Context, c2);
   EXPECT_NE(n1, n2);
-#ifdef ENABLE_MDNODE_UNIQUING
   EXPECT_EQ(n1, n3);
-#else
-  (void) n3;
-#endif
   EXPECT_EQ(n4, n1);
   EXPECT_EQ(n5, n2);
-  EXPECT_EQ(n6, (Value*)nullptr);
+  EXPECT_EQ(n6, (Metadata *)nullptr);
 
   EXPECT_EQ(3u, n1->getNumOperands());
   EXPECT_EQ(s1, n1->getOperand(0));
@@ -118,22 +160,1713 @@ TEST_F(MDNodeTest, Delete) {
   Constant *C = ConstantInt::get(Type::getInt32Ty(getGlobalContext()), 1);
   Instruction *I = new BitCastInst(C, Type::getInt32Ty(getGlobalContext()));
 
-  Value *const V = I;
+  Metadata *const V = LocalAsMetadata::get(I);
   MDNode *n = MDNode::get(Context, V);
-  WeakVH wvh = n;
+  TrackingMDRef wvh(n);
 
   EXPECT_EQ(n, wvh);
 
   delete I;
 }
 
+TEST_F(MDNodeTest, SelfReference) {
+  // !0 = !{!0}
+  // !1 = !{!0}
+  {
+    auto Temp = MDNode::getTemporary(Context, None);
+    Metadata *Args[] = {Temp.get()};
+    MDNode *Self = MDNode::get(Context, Args);
+    Self->replaceOperandWith(0, Self);
+    ASSERT_EQ(Self, Self->getOperand(0));
+
+    // Self-references should be distinct, so MDNode::get() should grab a
+    // uniqued node that references Self, not Self.
+    Args[0] = Self;
+    MDNode *Ref1 = MDNode::get(Context, Args);
+    MDNode *Ref2 = MDNode::get(Context, Args);
+    EXPECT_NE(Self, Ref1);
+    EXPECT_EQ(Ref1, Ref2);
+  }
+
+  // !0 = !{!0, !{}}
+  // !1 = !{!0, !{}}
+  {
+    auto Temp = MDNode::getTemporary(Context, None);
+    Metadata *Args[] = {Temp.get(), MDNode::get(Context, None)};
+    MDNode *Self = MDNode::get(Context, Args);
+    Self->replaceOperandWith(0, Self);
+    ASSERT_EQ(Self, Self->getOperand(0));
+
+    // Self-references should be distinct, so MDNode::get() should grab a
+    // uniqued node that references Self, not Self itself.
+    Args[0] = Self;
+    MDNode *Ref1 = MDNode::get(Context, Args);
+    MDNode *Ref2 = MDNode::get(Context, Args);
+    EXPECT_NE(Self, Ref1);
+    EXPECT_EQ(Ref1, Ref2);
+  }
+}
+
+TEST_F(MDNodeTest, Print) {
+  Constant *C = ConstantInt::get(Type::getInt32Ty(Context), 7);
+  MDString *S = MDString::get(Context, "foo");
+  MDNode *N0 = getNode();
+  MDNode *N1 = getNode(N0);
+  MDNode *N2 = getNode(N0, N1);
+
+  Metadata *Args[] = {ConstantAsMetadata::get(C), S, nullptr, N0, N1, N2};
+  MDNode *N = MDNode::get(Context, Args);
+
+  std::string Expected;
+  {
+    raw_string_ostream OS(Expected);
+    OS << "!{";
+    C->printAsOperand(OS);
+    OS << ", ";
+    S->printAsOperand(OS);
+    OS << ", null";
+    MDNode *Nodes[] = {N0, N1, N2};
+    for (auto *Node : Nodes)
+      OS << ", <" << (void *)Node << ">";
+    OS << "}";
+  }
+
+  std::string Actual;
+  {
+    raw_string_ostream OS(Actual);
+    N->print(OS);
+  }
+
+  EXPECT_EQ(Expected, Actual);
+}
+
+TEST_F(MDNodeTest, NullOperand) {
+  // metadata !{}
+  MDNode *Empty = MDNode::get(Context, None);
+
+  // metadata !{metadata !{}}
+  Metadata *Ops[] = {Empty};
+  MDNode *N = MDNode::get(Context, Ops);
+  ASSERT_EQ(Empty, N->getOperand(0));
+
+  // metadata !{metadata !{}} => metadata !{null}
+  N->replaceOperandWith(0, nullptr);
+  ASSERT_EQ(nullptr, N->getOperand(0));
+
+  // metadata !{null}
+  Ops[0] = nullptr;
+  MDNode *NullOp = MDNode::get(Context, Ops);
+  ASSERT_EQ(nullptr, NullOp->getOperand(0));
+  EXPECT_EQ(N, NullOp);
+}
+
+TEST_F(MDNodeTest, DistinctOnUniquingCollision) {
+  // !{}
+  MDNode *Empty = MDNode::get(Context, None);
+  ASSERT_TRUE(Empty->isResolved());
+  EXPECT_FALSE(Empty->isDistinct());
+
+  // !{!{}}
+  Metadata *Wrapped1Ops[] = {Empty};
+  MDNode *Wrapped1 = MDNode::get(Context, Wrapped1Ops);
+  ASSERT_EQ(Empty, Wrapped1->getOperand(0));
+  ASSERT_TRUE(Wrapped1->isResolved());
+  EXPECT_FALSE(Wrapped1->isDistinct());
+
+  // !{!{!{}}}
+  Metadata *Wrapped2Ops[] = {Wrapped1};
+  MDNode *Wrapped2 = MDNode::get(Context, Wrapped2Ops);
+  ASSERT_EQ(Wrapped1, Wrapped2->getOperand(0));
+  ASSERT_TRUE(Wrapped2->isResolved());
+  EXPECT_FALSE(Wrapped2->isDistinct());
+
+  // !{!{!{}}} => !{!{}}
+  Wrapped2->replaceOperandWith(0, Empty);
+  ASSERT_EQ(Empty, Wrapped2->getOperand(0));
+  EXPECT_TRUE(Wrapped2->isDistinct());
+  EXPECT_FALSE(Wrapped1->isDistinct());
+}
+
+TEST_F(MDNodeTest, getDistinct) {
+  // !{}
+  MDNode *Empty = MDNode::get(Context, None);
+  ASSERT_TRUE(Empty->isResolved());
+  ASSERT_FALSE(Empty->isDistinct());
+  ASSERT_EQ(Empty, MDNode::get(Context, None));
+
+  // distinct !{}
+  MDNode *Distinct1 = MDNode::getDistinct(Context, None);
+  MDNode *Distinct2 = MDNode::getDistinct(Context, None);
+  EXPECT_TRUE(Distinct1->isResolved());
+  EXPECT_TRUE(Distinct2->isDistinct());
+  EXPECT_NE(Empty, Distinct1);
+  EXPECT_NE(Empty, Distinct2);
+  EXPECT_NE(Distinct1, Distinct2);
+
+  // !{}
+  ASSERT_EQ(Empty, MDNode::get(Context, None));
+}
+
+TEST_F(MDNodeTest, isUniqued) {
+  MDNode *U = MDTuple::get(Context, None);
+  MDNode *D = MDTuple::getDistinct(Context, None);
+  auto T = MDTuple::getTemporary(Context, None);
+  EXPECT_TRUE(U->isUniqued());
+  EXPECT_FALSE(D->isUniqued());
+  EXPECT_FALSE(T->isUniqued());
+}
+
+TEST_F(MDNodeTest, isDistinct) {
+  MDNode *U = MDTuple::get(Context, None);
+  MDNode *D = MDTuple::getDistinct(Context, None);
+  auto T = MDTuple::getTemporary(Context, None);
+  EXPECT_FALSE(U->isDistinct());
+  EXPECT_TRUE(D->isDistinct());
+  EXPECT_FALSE(T->isDistinct());
+}
+
+TEST_F(MDNodeTest, isTemporary) {
+  MDNode *U = MDTuple::get(Context, None);
+  MDNode *D = MDTuple::getDistinct(Context, None);
+  auto T = MDTuple::getTemporary(Context, None);
+  EXPECT_FALSE(U->isTemporary());
+  EXPECT_FALSE(D->isTemporary());
+  EXPECT_TRUE(T->isTemporary());
+}
+
+TEST_F(MDNodeTest, getDistinctWithUnresolvedOperands) {
+  // temporary !{}
+  auto Temp = MDTuple::getTemporary(Context, None);
+  ASSERT_FALSE(Temp->isResolved());
+
+  // distinct !{temporary !{}}
+  Metadata *Ops[] = {Temp.get()};
+  MDNode *Distinct = MDNode::getDistinct(Context, Ops);
+  EXPECT_TRUE(Distinct->isResolved());
+  EXPECT_EQ(Temp.get(), Distinct->getOperand(0));
+
+  // temporary !{} => !{}
+  MDNode *Empty = MDNode::get(Context, None);
+  Temp->replaceAllUsesWith(Empty);
+  EXPECT_EQ(Empty, Distinct->getOperand(0));
+}
+
+TEST_F(MDNodeTest, handleChangedOperandRecursion) {
+  // !0 = !{}
+  MDNode *N0 = MDNode::get(Context, None);
+
+  // !1 = !{!3, null}
+  auto Temp3 = MDTuple::getTemporary(Context, None);
+  Metadata *Ops1[] = {Temp3.get(), nullptr};
+  MDNode *N1 = MDNode::get(Context, Ops1);
+
+  // !2 = !{!3, !0}
+  Metadata *Ops2[] = {Temp3.get(), N0};
+  MDNode *N2 = MDNode::get(Context, Ops2);
+
+  // !3 = !{!2}
+  Metadata *Ops3[] = {N2};
+  MDNode *N3 = MDNode::get(Context, Ops3);
+  Temp3->replaceAllUsesWith(N3);
+
+  // !4 = !{!1}
+  Metadata *Ops4[] = {N1};
+  MDNode *N4 = MDNode::get(Context, Ops4);
+
+  // Confirm that the cycle prevented RAUW from getting dropped.
+  EXPECT_TRUE(N0->isResolved());
+  EXPECT_FALSE(N1->isResolved());
+  EXPECT_FALSE(N2->isResolved());
+  EXPECT_FALSE(N3->isResolved());
+  EXPECT_FALSE(N4->isResolved());
+
+  // Create a couple of distinct nodes to observe what's going on.
+  //
+  // !5 = distinct !{!2}
+  // !6 = distinct !{!3}
+  Metadata *Ops5[] = {N2};
+  MDNode *N5 = MDNode::getDistinct(Context, Ops5);
+  Metadata *Ops6[] = {N3};
+  MDNode *N6 = MDNode::getDistinct(Context, Ops6);
+
+  // Mutate !2 to look like !1, causing a uniquing collision (and an RAUW).
+  // This will ripple up, with !3 colliding with !4, and RAUWing.  Since !2
+  // references !3, this can cause a re-entry of handleChangedOperand() when !3
+  // is not ready for it.
+  //
+  // !2->replaceOperandWith(1, nullptr)
+  // !2: !{!3, !0} => !{!3, null}
+  // !2->replaceAllUsesWith(!1)
+  // !3: !{!2] => !{!1}
+  // !3->replaceAllUsesWith(!4)
+  N2->replaceOperandWith(1, nullptr);
+
+  // If all has gone well, N2 and N3 will have been RAUW'ed and deleted from
+  // under us.  Just check that the other nodes are sane.
+  //
+  // !1 = !{!4, null}
+  // !4 = !{!1}
+  // !5 = distinct !{!1}
+  // !6 = distinct !{!4}
+  EXPECT_EQ(N4, N1->getOperand(0));
+  EXPECT_EQ(N1, N4->getOperand(0));
+  EXPECT_EQ(N1, N5->getOperand(0));
+  EXPECT_EQ(N4, N6->getOperand(0));
+}
+
+TEST_F(MDNodeTest, replaceResolvedOperand) {
+  // Check code for replacing one resolved operand with another.  If doing this
+  // directly (via replaceOperandWith()) becomes illegal, change the operand to
+  // a global value that gets RAUW'ed.
+  //
+  // Use a temporary node to keep N from being resolved.
+  auto Temp = MDTuple::getTemporary(Context, None);
+  Metadata *Ops[] = {nullptr, Temp.get()};
+
+  MDNode *Empty = MDTuple::get(Context, ArrayRef<Metadata *>());
+  MDNode *N = MDTuple::get(Context, Ops);
+  EXPECT_EQ(nullptr, N->getOperand(0));
+  ASSERT_FALSE(N->isResolved());
+
+  // Check code for replacing resolved nodes.
+  N->replaceOperandWith(0, Empty);
+  EXPECT_EQ(Empty, N->getOperand(0));
+
+  // Check code for adding another unresolved operand.
+  N->replaceOperandWith(0, Temp.get());
+  EXPECT_EQ(Temp.get(), N->getOperand(0));
+
+  // Remove the references to Temp; required for teardown.
+  Temp->replaceAllUsesWith(nullptr);
+}
+
+TEST_F(MDNodeTest, replaceWithUniqued) {
+  auto *Empty = MDTuple::get(Context, None);
+  MDTuple *FirstUniqued;
+  {
+    Metadata *Ops[] = {Empty};
+    auto Temp = MDTuple::getTemporary(Context, Ops);
+    EXPECT_TRUE(Temp->isTemporary());
+
+    // Don't expect a collision.
+    auto *Current = Temp.get();
+    FirstUniqued = MDNode::replaceWithUniqued(std::move(Temp));
+    EXPECT_TRUE(FirstUniqued->isUniqued());
+    EXPECT_TRUE(FirstUniqued->isResolved());
+    EXPECT_EQ(Current, FirstUniqued);
+  }
+  {
+    Metadata *Ops[] = {Empty};
+    auto Temp = MDTuple::getTemporary(Context, Ops);
+    EXPECT_TRUE(Temp->isTemporary());
+
+    // Should collide with Uniqued above this time.
+    auto *Uniqued = MDNode::replaceWithUniqued(std::move(Temp));
+    EXPECT_TRUE(Uniqued->isUniqued());
+    EXPECT_TRUE(Uniqued->isResolved());
+    EXPECT_EQ(FirstUniqued, Uniqued);
+  }
+  {
+    auto Unresolved = MDTuple::getTemporary(Context, None);
+    Metadata *Ops[] = {Unresolved.get()};
+    auto Temp = MDTuple::getTemporary(Context, Ops);
+    EXPECT_TRUE(Temp->isTemporary());
+
+    // Shouldn't be resolved.
+    auto *Uniqued = MDNode::replaceWithUniqued(std::move(Temp));
+    EXPECT_TRUE(Uniqued->isUniqued());
+    EXPECT_FALSE(Uniqued->isResolved());
+
+    // Should be a different node.
+    EXPECT_NE(FirstUniqued, Uniqued);
+
+    // Should resolve when we update its node (note: be careful to avoid a
+    // collision with any other nodes above).
+    Uniqued->replaceOperandWith(0, nullptr);
+    EXPECT_TRUE(Uniqued->isResolved());
+  }
+}
+
+TEST_F(MDNodeTest, replaceWithDistinct) {
+  {
+    auto *Empty = MDTuple::get(Context, None);
+    Metadata *Ops[] = {Empty};
+    auto Temp = MDTuple::getTemporary(Context, Ops);
+    EXPECT_TRUE(Temp->isTemporary());
+
+    // Don't expect a collision.
+    auto *Current = Temp.get();
+    auto *Distinct = MDNode::replaceWithDistinct(std::move(Temp));
+    EXPECT_TRUE(Distinct->isDistinct());
+    EXPECT_TRUE(Distinct->isResolved());
+    EXPECT_EQ(Current, Distinct);
+  }
+  {
+    auto Unresolved = MDTuple::getTemporary(Context, None);
+    Metadata *Ops[] = {Unresolved.get()};
+    auto Temp = MDTuple::getTemporary(Context, Ops);
+    EXPECT_TRUE(Temp->isTemporary());
+
+    // Don't expect a collision.
+    auto *Current = Temp.get();
+    auto *Distinct = MDNode::replaceWithDistinct(std::move(Temp));
+    EXPECT_TRUE(Distinct->isDistinct());
+    EXPECT_TRUE(Distinct->isResolved());
+    EXPECT_EQ(Current, Distinct);
+
+    // Cleanup; required for teardown.
+    Unresolved->replaceAllUsesWith(nullptr);
+  }
+}
+
+TEST_F(MDNodeTest, replaceWithPermanent) {
+  Metadata *Ops[] = {nullptr};
+  auto Temp = MDTuple::getTemporary(Context, Ops);
+  auto *T = Temp.get();
+
+  // U is a normal, uniqued node that references T.
+  auto *U = MDTuple::get(Context, T);
+  EXPECT_TRUE(U->isUniqued());
+
+  // Make Temp self-referencing.
+  Temp->replaceOperandWith(0, T);
+
+  // Try to uniquify Temp.  This should, despite the name in the API, give a
+  // 'distinct' node, since self-references aren't allowed to be uniqued.
+  //
+  // Since it's distinct, N should have the same address as when it was a
+  // temporary (i.e., be equal to T not U).
+  auto *N = MDNode::replaceWithPermanent(std::move(Temp));
+  EXPECT_EQ(N, T);
+  EXPECT_TRUE(N->isDistinct());
+
+  // U should be the canonical unique node with N as the argument.
+  EXPECT_EQ(U, MDTuple::get(Context, N));
+  EXPECT_TRUE(U->isUniqued());
+
+  // This temporary should collide with U when replaced, but it should still be
+  // uniqued.
+  EXPECT_EQ(U, MDNode::replaceWithPermanent(MDTuple::getTemporary(Context, N)));
+  EXPECT_TRUE(U->isUniqued());
+
+  // This temporary should become a new uniqued node.
+  auto Temp2 = MDTuple::getTemporary(Context, U);
+  auto *V = Temp2.get();
+  EXPECT_EQ(V, MDNode::replaceWithPermanent(std::move(Temp2)));
+  EXPECT_TRUE(V->isUniqued());
+  EXPECT_EQ(U, V->getOperand(0));
+}
+
+TEST_F(MDNodeTest, deleteTemporaryWithTrackingRef) {
+  TrackingMDRef Ref;
+  EXPECT_EQ(nullptr, Ref.get());
+  {
+    auto Temp = MDTuple::getTemporary(Context, None);
+    Ref.reset(Temp.get());
+    EXPECT_EQ(Temp.get(), Ref.get());
+  }
+  EXPECT_EQ(nullptr, Ref.get());
+}
+
+typedef MetadataTest MDLocationTest;
+
+TEST_F(MDLocationTest, Overflow) {
+  MDNode *N = MDNode::get(Context, None);
+  {
+    MDLocation *L = MDLocation::get(Context, 2, 7, N);
+    EXPECT_EQ(2u, L->getLine());
+    EXPECT_EQ(7u, L->getColumn());
+  }
+  unsigned U16 = 1u << 16;
+  {
+    MDLocation *L = MDLocation::get(Context, UINT32_MAX, U16 - 1, N);
+    EXPECT_EQ(UINT32_MAX, L->getLine());
+    EXPECT_EQ(U16 - 1, L->getColumn());
+  }
+  {
+    MDLocation *L = MDLocation::get(Context, UINT32_MAX, U16, N);
+    EXPECT_EQ(UINT32_MAX, L->getLine());
+    EXPECT_EQ(0u, L->getColumn());
+  }
+  {
+    MDLocation *L = MDLocation::get(Context, UINT32_MAX, U16 + 1, N);
+    EXPECT_EQ(UINT32_MAX, L->getLine());
+    EXPECT_EQ(0u, L->getColumn());
+  }
+}
+
+TEST_F(MDLocationTest, getDistinct) {
+  MDNode *N = MDNode::get(Context, None);
+  MDLocation *L0 = MDLocation::getDistinct(Context, 2, 7, N);
+  EXPECT_TRUE(L0->isDistinct());
+  MDLocation *L1 = MDLocation::get(Context, 2, 7, N);
+  EXPECT_FALSE(L1->isDistinct());
+  EXPECT_EQ(L1, MDLocation::get(Context, 2, 7, N));
+}
+
+TEST_F(MDLocationTest, getTemporary) {
+  MDNode *N = MDNode::get(Context, None);
+  auto L = MDLocation::getTemporary(Context, 2, 7, N);
+  EXPECT_TRUE(L->isTemporary());
+  EXPECT_FALSE(L->isResolved());
+}
+
+typedef MetadataTest GenericDebugNodeTest;
+
+TEST_F(GenericDebugNodeTest, get) {
+  StringRef Header = "header";
+  auto *Empty = MDNode::get(Context, None);
+  Metadata *Ops1[] = {Empty};
+  auto *N = GenericDebugNode::get(Context, 15, Header, Ops1);
+  EXPECT_EQ(15u, N->getTag());
+  EXPECT_EQ(2u, N->getNumOperands());
+  EXPECT_EQ(Header, N->getHeader());
+  EXPECT_EQ(MDString::get(Context, Header), N->getOperand(0));
+  EXPECT_EQ(1u, N->getNumDwarfOperands());
+  EXPECT_EQ(Empty, N->getDwarfOperand(0));
+  EXPECT_EQ(Empty, N->getOperand(1));
+  ASSERT_TRUE(N->isUniqued());
+
+  EXPECT_EQ(N, GenericDebugNode::get(Context, 15, Header, Ops1));
+
+  N->replaceOperandWith(1, nullptr);
+  EXPECT_EQ(15u, N->getTag());
+  EXPECT_EQ(Header, N->getHeader());
+  EXPECT_EQ(nullptr, N->getDwarfOperand(0));
+  ASSERT_TRUE(N->isUniqued());
+
+  Metadata *Ops2[] = {nullptr};
+  EXPECT_EQ(N, GenericDebugNode::get(Context, 15, Header, Ops2));
+
+  N->replaceDwarfOperandWith(0, Empty);
+  EXPECT_EQ(15u, N->getTag());
+  EXPECT_EQ(Header, N->getHeader());
+  EXPECT_EQ(Empty, N->getDwarfOperand(0));
+  ASSERT_TRUE(N->isUniqued());
+  EXPECT_EQ(N, GenericDebugNode::get(Context, 15, Header, Ops1));
+
+  TempGenericDebugNode Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(GenericDebugNodeTest, getEmptyHeader) {
+  // Canonicalize !"" to null.
+  auto *N = GenericDebugNode::get(Context, 15, StringRef(), None);
+  EXPECT_EQ(StringRef(), N->getHeader());
+  EXPECT_EQ(nullptr, N->getOperand(0));
+}
+
+typedef MetadataTest MDSubrangeTest;
+
+TEST_F(MDSubrangeTest, get) {
+  auto *N = MDSubrange::get(Context, 5, 7);
+  EXPECT_EQ(dwarf::DW_TAG_subrange_type, N->getTag());
+  EXPECT_EQ(5, N->getCount());
+  EXPECT_EQ(7, N->getLo());
+  EXPECT_EQ(N, MDSubrange::get(Context, 5, 7));
+  EXPECT_EQ(MDSubrange::get(Context, 5, 0), MDSubrange::get(Context, 5));
+
+  TempMDSubrange Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(MDSubrangeTest, getEmptyArray) {
+  auto *N = MDSubrange::get(Context, -1, 0);
+  EXPECT_EQ(dwarf::DW_TAG_subrange_type, N->getTag());
+  EXPECT_EQ(-1, N->getCount());
+  EXPECT_EQ(0, N->getLo());
+  EXPECT_EQ(N, MDSubrange::get(Context, -1, 0));
+}
+
+typedef MetadataTest MDEnumeratorTest;
+
+TEST_F(MDEnumeratorTest, get) {
+  auto *N = MDEnumerator::get(Context, 7, "name");
+  EXPECT_EQ(dwarf::DW_TAG_enumerator, N->getTag());
+  EXPECT_EQ(7, N->getValue());
+  EXPECT_EQ("name", N->getName());
+  EXPECT_EQ(N, MDEnumerator::get(Context, 7, "name"));
+
+  EXPECT_NE(N, MDEnumerator::get(Context, 8, "name"));
+  EXPECT_NE(N, MDEnumerator::get(Context, 7, "nam"));
+
+  TempMDEnumerator Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest MDBasicTypeTest;
+
+TEST_F(MDBasicTypeTest, get) {
+  auto *N =
+      MDBasicType::get(Context, dwarf::DW_TAG_base_type, "special", 33, 26, 7);
+  EXPECT_EQ(dwarf::DW_TAG_base_type, N->getTag());
+  EXPECT_EQ("special", N->getName());
+  EXPECT_EQ(33u, N->getSizeInBits());
+  EXPECT_EQ(26u, N->getAlignInBits());
+  EXPECT_EQ(7u, N->getEncoding());
+  EXPECT_EQ(0u, N->getLine());
+  EXPECT_EQ(N, MDBasicType::get(Context, dwarf::DW_TAG_base_type, "special", 33,
+                                26, 7));
+
+  EXPECT_NE(N, MDBasicType::get(Context, dwarf::DW_TAG_unspecified_type,
+                                "special", 33, 26, 7));
+  EXPECT_NE(N,
+            MDBasicType::get(Context, dwarf::DW_TAG_base_type, "s", 33, 26, 7));
+  EXPECT_NE(N, MDBasicType::get(Context, dwarf::DW_TAG_base_type, "special", 32,
+                                26, 7));
+  EXPECT_NE(N, MDBasicType::get(Context, dwarf::DW_TAG_base_type, "special", 33,
+                                25, 7));
+  EXPECT_NE(N, MDBasicType::get(Context, dwarf::DW_TAG_base_type, "special", 33,
+                                26, 6));
+
+  TempMDBasicType Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(MDBasicTypeTest, getWithLargeValues) {
+  auto *N = MDBasicType::get(Context, dwarf::DW_TAG_base_type, "special",
+                             UINT64_MAX, UINT64_MAX - 1, 7);
+  EXPECT_EQ(UINT64_MAX, N->getSizeInBits());
+  EXPECT_EQ(UINT64_MAX - 1, N->getAlignInBits());
+}
+
+typedef MetadataTest MDDerivedTypeTest;
+
+TEST_F(MDDerivedTypeTest, get) {
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  Metadata *BaseType = MDTuple::getDistinct(Context, None);
+  Metadata *ExtraData = MDTuple::getDistinct(Context, None);
+
+  auto *N = MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type, "something",
+                               File, 1, Scope, BaseType, 2, 3, 4, 5, ExtraData);
+  EXPECT_EQ(dwarf::DW_TAG_pointer_type, N->getTag());
+  EXPECT_EQ("something", N->getName());
+  EXPECT_EQ(File, N->getFile());
+  EXPECT_EQ(1u, N->getLine());
+  EXPECT_EQ(Scope, N->getScope());
+  EXPECT_EQ(BaseType, N->getBaseType());
+  EXPECT_EQ(2u, N->getSizeInBits());
+  EXPECT_EQ(3u, N->getAlignInBits());
+  EXPECT_EQ(4u, N->getOffsetInBits());
+  EXPECT_EQ(5u, N->getFlags());
+  EXPECT_EQ(ExtraData, N->getExtraData());
+  EXPECT_EQ(N, MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 1, Scope, BaseType, 2, 3,
+                                  4, 5, ExtraData));
+
+  EXPECT_NE(N, MDDerivedType::get(Context, dwarf::DW_TAG_reference_type,
+                                  "something", File, 1, Scope, BaseType, 2, 3,
+                                  4, 5, ExtraData));
+  EXPECT_NE(N, MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type, "else",
+                                  File, 1, Scope, BaseType, 2, 3, 4, 5,
+                                  ExtraData));
+  EXPECT_NE(N, MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", Scope, 1, Scope, BaseType, 2, 3,
+                                  4, 5, ExtraData));
+  EXPECT_NE(N, MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 2, Scope, BaseType, 2, 3,
+                                  4, 5, ExtraData));
+  EXPECT_NE(N,
+            MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type, "something",
+                               File, 1, File, BaseType, 2, 3, 4, 5, ExtraData));
+  EXPECT_NE(N,
+            MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type, "something",
+                               File, 1, Scope, File, 2, 3, 4, 5, ExtraData));
+  EXPECT_NE(N, MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 1, Scope, BaseType, 3, 3,
+                                  4, 5, ExtraData));
+  EXPECT_NE(N, MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 1, Scope, BaseType, 2, 2,
+                                  4, 5, ExtraData));
+  EXPECT_NE(N, MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 1, Scope, BaseType, 2, 3,
+                                  5, 5, ExtraData));
+  EXPECT_NE(N, MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 1, Scope, BaseType, 2, 3,
+                                  4, 4, ExtraData));
+  EXPECT_NE(N,
+            MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type, "something",
+                               File, 1, Scope, BaseType, 2, 3, 4, 5, File));
+
+  TempMDDerivedType Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(MDDerivedTypeTest, getWithLargeValues) {
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  Metadata *BaseType = MDTuple::getDistinct(Context, None);
+  Metadata *ExtraData = MDTuple::getDistinct(Context, None);
+
+  auto *N = MDDerivedType::get(Context, dwarf::DW_TAG_pointer_type, "something",
+                               File, 1, Scope, BaseType, UINT64_MAX,
+                               UINT64_MAX - 1, UINT64_MAX - 2, 5, ExtraData);
+  EXPECT_EQ(UINT64_MAX, N->getSizeInBits());
+  EXPECT_EQ(UINT64_MAX - 1, N->getAlignInBits());
+  EXPECT_EQ(UINT64_MAX - 2, N->getOffsetInBits());
+}
+
+typedef MetadataTest MDCompositeTypeTest;
+
+TEST_F(MDCompositeTypeTest, get) {
+  unsigned Tag = dwarf::DW_TAG_structure_type;
+  StringRef Name = "some name";
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  unsigned Line = 1;
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  Metadata *BaseType = MDTuple::getDistinct(Context, None);
+  uint64_t SizeInBits = 2;
+  uint64_t AlignInBits = 3;
+  uint64_t OffsetInBits = 4;
+  unsigned Flags = 5;
+  Metadata *Elements = MDTuple::getDistinct(Context, None);
+  unsigned RuntimeLang = 6;
+  Metadata *VTableHolder = MDTuple::getDistinct(Context, None);
+  Metadata *TemplateParams = MDTuple::getDistinct(Context, None);
+  StringRef Identifier = "some id";
+
+  auto *N = MDCompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                 BaseType, SizeInBits, AlignInBits,
+                                 OffsetInBits, Flags, Elements, RuntimeLang,
+                                 VTableHolder, TemplateParams, Identifier);
+  EXPECT_EQ(Tag, N->getTag());
+  EXPECT_EQ(Name, N->getName());
+  EXPECT_EQ(File, N->getFile());
+  EXPECT_EQ(Line, N->getLine());
+  EXPECT_EQ(Scope, N->getScope());
+  EXPECT_EQ(BaseType, N->getBaseType());
+  EXPECT_EQ(SizeInBits, N->getSizeInBits());
+  EXPECT_EQ(AlignInBits, N->getAlignInBits());
+  EXPECT_EQ(OffsetInBits, N->getOffsetInBits());
+  EXPECT_EQ(Flags, N->getFlags());
+  EXPECT_EQ(Elements, N->getElements());
+  EXPECT_EQ(RuntimeLang, N->getRuntimeLang());
+  EXPECT_EQ(VTableHolder, N->getVTableHolder());
+  EXPECT_EQ(TemplateParams, N->getTemplateParams());
+  EXPECT_EQ(Identifier, N->getIdentifier());
+
+  EXPECT_EQ(N, MDCompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+
+  EXPECT_NE(N, MDCompositeType::get(Context, Tag + 1, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(Context, Tag, "abc", File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(Context, Tag, Name, Scope, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(Context, Tag, Name, File, Line + 1, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(Context, Tag, Name, File, Line, File,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(Context, Tag, Name, File, Line, Scope, File,
+                                    SizeInBits, AlignInBits, OffsetInBits,
+                                    Flags, Elements, RuntimeLang, VTableHolder,
+                                    TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits + 1, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits + 1,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(
+                   Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
+                   AlignInBits, OffsetInBits + 1, Flags, Elements, RuntimeLang,
+                   VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(
+                   Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
+                   AlignInBits, OffsetInBits, Flags + 1, Elements, RuntimeLang,
+                   VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, File, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(
+                   Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
+                   AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang + 1,
+                   VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    File, TemplateParams, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, File, Identifier));
+  EXPECT_NE(N, MDCompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, "other"));
+
+  // Be sure that missing identifiers get null pointers.
+  EXPECT_FALSE(MDCompositeType::get(
+                   Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
+                   AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang,
+                   VTableHolder, TemplateParams, "")->getRawIdentifier());
+  EXPECT_FALSE(MDCompositeType::get(
+                   Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
+                   AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang,
+                   VTableHolder, TemplateParams)->getRawIdentifier());
+
+  TempMDCompositeType Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(MDCompositeTypeTest, getWithLargeValues) {
+  unsigned Tag = dwarf::DW_TAG_structure_type;
+  StringRef Name = "some name";
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  unsigned Line = 1;
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  Metadata *BaseType = MDTuple::getDistinct(Context, None);
+  uint64_t SizeInBits = UINT64_MAX;
+  uint64_t AlignInBits = UINT64_MAX - 1;
+  uint64_t OffsetInBits = UINT64_MAX - 2;
+  unsigned Flags = 5;
+  Metadata *Elements = MDTuple::getDistinct(Context, None);
+  unsigned RuntimeLang = 6;
+  Metadata *VTableHolder = MDTuple::getDistinct(Context, None);
+  Metadata *TemplateParams = MDTuple::getDistinct(Context, None);
+  StringRef Identifier = "some id";
+
+  auto *N = MDCompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                 BaseType, SizeInBits, AlignInBits,
+                                 OffsetInBits, Flags, Elements, RuntimeLang,
+                                 VTableHolder, TemplateParams, Identifier);
+  EXPECT_EQ(SizeInBits, N->getSizeInBits());
+  EXPECT_EQ(AlignInBits, N->getAlignInBits());
+  EXPECT_EQ(OffsetInBits, N->getOffsetInBits());
+}
+
+TEST_F(MDCompositeTypeTest, replaceOperands) {
+  unsigned Tag = dwarf::DW_TAG_structure_type;
+  StringRef Name = "some name";
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  unsigned Line = 1;
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  Metadata *BaseType = MDTuple::getDistinct(Context, None);
+  uint64_t SizeInBits = 2;
+  uint64_t AlignInBits = 3;
+  uint64_t OffsetInBits = 4;
+  unsigned Flags = 5;
+  unsigned RuntimeLang = 6;
+  StringRef Identifier = "some id";
+
+  auto *N = MDCompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                 BaseType, SizeInBits, AlignInBits,
+                                 OffsetInBits, Flags, nullptr, RuntimeLang,
+                                 nullptr, nullptr, Identifier);
+
+  auto *Elements = MDTuple::getDistinct(Context, None);
+  EXPECT_EQ(nullptr, N->getElements());
+  N->replaceElements(Elements);
+  EXPECT_EQ(Elements, N->getElements());
+  N->replaceElements(nullptr);
+  EXPECT_EQ(nullptr, N->getElements());
+
+  auto *VTableHolder = MDTuple::getDistinct(Context, None);
+  EXPECT_EQ(nullptr, N->getVTableHolder());
+  N->replaceVTableHolder(VTableHolder);
+  EXPECT_EQ(VTableHolder, N->getVTableHolder());
+  N->replaceVTableHolder(nullptr);
+  EXPECT_EQ(nullptr, N->getVTableHolder());
+
+  auto *TemplateParams = MDTuple::getDistinct(Context, None);
+  EXPECT_EQ(nullptr, N->getTemplateParams());
+  N->replaceTemplateParams(TemplateParams);
+  EXPECT_EQ(TemplateParams, N->getTemplateParams());
+  N->replaceTemplateParams(nullptr);
+  EXPECT_EQ(nullptr, N->getTemplateParams());
+}
+
+typedef MetadataTest MDSubroutineTypeTest;
+
+TEST_F(MDSubroutineTypeTest, get) {
+  unsigned Flags = 1;
+  Metadata *TypeArray = MDTuple::getDistinct(Context, None);
+
+  auto *N = MDSubroutineType::get(Context, Flags, TypeArray);
+  EXPECT_EQ(dwarf::DW_TAG_subroutine_type, N->getTag());
+  EXPECT_EQ(Flags, N->getFlags());
+  EXPECT_EQ(TypeArray, N->getTypeArray());
+  EXPECT_EQ(N, MDSubroutineType::get(Context, Flags, TypeArray));
+
+  EXPECT_NE(N, MDSubroutineType::get(Context, Flags + 1, TypeArray));
+  EXPECT_NE(N, MDSubroutineType::get(Context, Flags,
+                                     MDTuple::getDistinct(Context, None)));
+
+  TempMDSubroutineType Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+
+  // Test always-empty operands.
+  EXPECT_EQ(nullptr, N->getScope());
+  EXPECT_EQ(nullptr, N->getFile());
+  EXPECT_EQ("", N->getName());
+  EXPECT_EQ(nullptr, N->getBaseType());
+  EXPECT_EQ(nullptr, N->getVTableHolder());
+  EXPECT_EQ(nullptr, N->getTemplateParams());
+  EXPECT_EQ("", N->getIdentifier());
+}
+
+typedef MetadataTest MDFileTest;
+
+TEST_F(MDFileTest, get) {
+  StringRef Filename = "file";
+  StringRef Directory = "dir";
+  auto *N = MDFile::get(Context, Filename, Directory);
+
+  EXPECT_EQ(dwarf::DW_TAG_file_type, N->getTag());
+  EXPECT_EQ(Filename, N->getFilename());
+  EXPECT_EQ(Directory, N->getDirectory());
+  EXPECT_EQ(N, MDFile::get(Context, Filename, Directory));
+
+  EXPECT_NE(N, MDFile::get(Context, "other", Directory));
+  EXPECT_NE(N, MDFile::get(Context, Filename, "other"));
+
+  TempMDFile Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest MDCompileUnitTest;
+
+TEST_F(MDCompileUnitTest, get) {
+  unsigned SourceLanguage = 1;
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  StringRef Producer = "some producer";
+  bool IsOptimized = false;
+  StringRef Flags = "flag after flag";
+  unsigned RuntimeVersion = 2;
+  StringRef SplitDebugFilename = "another/file";
+  unsigned EmissionKind = 3;
+  Metadata *EnumTypes = MDTuple::getDistinct(Context, None);
+  Metadata *RetainedTypes = MDTuple::getDistinct(Context, None);
+  Metadata *Subprograms = MDTuple::getDistinct(Context, None);
+  Metadata *GlobalVariables = MDTuple::getDistinct(Context, None);
+  Metadata *ImportedEntities = MDTuple::getDistinct(Context, None);
+  auto *N = MDCompileUnit::get(
+      Context, SourceLanguage, File, Producer, IsOptimized, Flags,
+      RuntimeVersion, SplitDebugFilename, EmissionKind, EnumTypes,
+      RetainedTypes, Subprograms, GlobalVariables, ImportedEntities);
+
+  EXPECT_EQ(dwarf::DW_TAG_compile_unit, N->getTag());
+  EXPECT_EQ(SourceLanguage, N->getSourceLanguage());
+  EXPECT_EQ(File, N->getFile());
+  EXPECT_EQ(Producer, N->getProducer());
+  EXPECT_EQ(IsOptimized, N->isOptimized());
+  EXPECT_EQ(Flags, N->getFlags());
+  EXPECT_EQ(RuntimeVersion, N->getRuntimeVersion());
+  EXPECT_EQ(SplitDebugFilename, N->getSplitDebugFilename());
+  EXPECT_EQ(EmissionKind, N->getEmissionKind());
+  EXPECT_EQ(EnumTypes, N->getEnumTypes());
+  EXPECT_EQ(RetainedTypes, N->getRetainedTypes());
+  EXPECT_EQ(Subprograms, N->getSubprograms());
+  EXPECT_EQ(GlobalVariables, N->getGlobalVariables());
+  EXPECT_EQ(ImportedEntities, N->getImportedEntities());
+  EXPECT_EQ(N, MDCompileUnit::get(Context, SourceLanguage, File, Producer,
+                                  IsOptimized, Flags, RuntimeVersion,
+                                  SplitDebugFilename, EmissionKind, EnumTypes,
+                                  RetainedTypes, Subprograms, GlobalVariables,
+                                  ImportedEntities));
+
+  EXPECT_NE(N, MDCompileUnit::get(Context, SourceLanguage + 1, File, Producer,
+                                  IsOptimized, Flags, RuntimeVersion,
+                                  SplitDebugFilename, EmissionKind, EnumTypes,
+                                  RetainedTypes, Subprograms, GlobalVariables,
+                                  ImportedEntities));
+  EXPECT_NE(N, MDCompileUnit::get(Context, SourceLanguage, EnumTypes, Producer,
+                                  IsOptimized, Flags, RuntimeVersion,
+                                  SplitDebugFilename, EmissionKind, EnumTypes,
+                                  RetainedTypes, Subprograms, GlobalVariables,
+                                  ImportedEntities));
+  EXPECT_NE(N, MDCompileUnit::get(Context, SourceLanguage, File, "other",
+                                  IsOptimized, Flags, RuntimeVersion,
+                                  SplitDebugFilename, EmissionKind, EnumTypes,
+                                  RetainedTypes, Subprograms, GlobalVariables,
+                                  ImportedEntities));
+  EXPECT_NE(N, MDCompileUnit::get(Context, SourceLanguage, File, Producer,
+                                  !IsOptimized, Flags, RuntimeVersion,
+                                  SplitDebugFilename, EmissionKind, EnumTypes,
+                                  RetainedTypes, Subprograms, GlobalVariables,
+                                  ImportedEntities));
+  EXPECT_NE(N, MDCompileUnit::get(Context, SourceLanguage, File, Producer,
+                                  IsOptimized, "other", RuntimeVersion,
+                                  SplitDebugFilename, EmissionKind, EnumTypes,
+                                  RetainedTypes, Subprograms, GlobalVariables,
+                                  ImportedEntities));
+  EXPECT_NE(N, MDCompileUnit::get(Context, SourceLanguage, File, Producer,
+                                  IsOptimized, Flags, RuntimeVersion + 1,
+                                  SplitDebugFilename, EmissionKind, EnumTypes,
+                                  RetainedTypes, Subprograms, GlobalVariables,
+                                  ImportedEntities));
+  EXPECT_NE(N,
+            MDCompileUnit::get(Context, SourceLanguage, File, Producer,
+                               IsOptimized, Flags, RuntimeVersion, "other",
+                               EmissionKind, EnumTypes, RetainedTypes,
+                               Subprograms, GlobalVariables, ImportedEntities));
+  EXPECT_NE(N, MDCompileUnit::get(Context, SourceLanguage, File, Producer,
+                                  IsOptimized, Flags, RuntimeVersion,
+                                  SplitDebugFilename, EmissionKind + 1,
+                                  EnumTypes, RetainedTypes, Subprograms,
+                                  GlobalVariables, ImportedEntities));
+  EXPECT_NE(N, MDCompileUnit::get(Context, SourceLanguage, File, Producer,
+                                  IsOptimized, Flags, RuntimeVersion,
+                                  SplitDebugFilename, EmissionKind, File,
+                                  RetainedTypes, Subprograms, GlobalVariables,
+                                  ImportedEntities));
+  EXPECT_NE(N, MDCompileUnit::get(
+                   Context, SourceLanguage, File, Producer, IsOptimized, Flags,
+                   RuntimeVersion, SplitDebugFilename, EmissionKind, EnumTypes,
+                   File, Subprograms, GlobalVariables, ImportedEntities));
+  EXPECT_NE(N, MDCompileUnit::get(
+                   Context, SourceLanguage, File, Producer, IsOptimized, Flags,
+                   RuntimeVersion, SplitDebugFilename, EmissionKind, EnumTypes,
+                   RetainedTypes, File, GlobalVariables, ImportedEntities));
+  EXPECT_NE(N, MDCompileUnit::get(
+                   Context, SourceLanguage, File, Producer, IsOptimized, Flags,
+                   RuntimeVersion, SplitDebugFilename, EmissionKind, EnumTypes,
+                   RetainedTypes, Subprograms, File, ImportedEntities));
+  EXPECT_NE(N, MDCompileUnit::get(
+                   Context, SourceLanguage, File, Producer, IsOptimized, Flags,
+                   RuntimeVersion, SplitDebugFilename, EmissionKind, EnumTypes,
+                   RetainedTypes, Subprograms, GlobalVariables, File));
+
+  TempMDCompileUnit Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(MDCompileUnitTest, replaceArrays) {
+  unsigned SourceLanguage = 1;
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  StringRef Producer = "some producer";
+  bool IsOptimized = false;
+  StringRef Flags = "flag after flag";
+  unsigned RuntimeVersion = 2;
+  StringRef SplitDebugFilename = "another/file";
+  unsigned EmissionKind = 3;
+  Metadata *EnumTypes = MDTuple::getDistinct(Context, None);
+  Metadata *RetainedTypes = MDTuple::getDistinct(Context, None);
+  Metadata *ImportedEntities = MDTuple::getDistinct(Context, None);
+  auto *N = MDCompileUnit::get(
+      Context, SourceLanguage, File, Producer, IsOptimized, Flags,
+      RuntimeVersion, SplitDebugFilename, EmissionKind, EnumTypes,
+      RetainedTypes, nullptr, nullptr, ImportedEntities);
+
+  auto *Subprograms = MDTuple::getDistinct(Context, None);
+  EXPECT_EQ(nullptr, N->getSubprograms());
+  N->replaceSubprograms(Subprograms);
+  EXPECT_EQ(Subprograms, N->getSubprograms());
+  N->replaceSubprograms(nullptr);
+  EXPECT_EQ(nullptr, N->getSubprograms());
+
+  auto *GlobalVariables = MDTuple::getDistinct(Context, None);
+  EXPECT_EQ(nullptr, N->getGlobalVariables());
+  N->replaceGlobalVariables(GlobalVariables);
+  EXPECT_EQ(GlobalVariables, N->getGlobalVariables());
+  N->replaceGlobalVariables(nullptr);
+  EXPECT_EQ(nullptr, N->getGlobalVariables());
+}
+
+typedef MetadataTest MDSubprogramTest;
+
+TEST_F(MDSubprogramTest, get) {
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  StringRef Name = "name";
+  StringRef LinkageName = "linkage";
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  unsigned Line = 2;
+  Metadata *Type = MDTuple::getDistinct(Context, None);
+  bool IsLocalToUnit = false;
+  bool IsDefinition = true;
+  unsigned ScopeLine = 3;
+  Metadata *ContainingType = MDTuple::getDistinct(Context, None);
+  unsigned Virtuality = 4;
+  unsigned VirtualIndex = 5;
+  unsigned Flags = 6;
+  bool IsOptimized = false;
+  Metadata *Function = MDTuple::getDistinct(Context, None);
+  Metadata *TemplateParams = MDTuple::getDistinct(Context, None);
+  Metadata *Declaration = MDTuple::getDistinct(Context, None);
+  Metadata *Variables = MDTuple::getDistinct(Context, None);
+
+  auto *N = MDSubprogram::get(
+      Context, Scope, Name, LinkageName, File, Line, Type, IsLocalToUnit,
+      IsDefinition, ScopeLine, ContainingType, Virtuality, VirtualIndex, Flags,
+      IsOptimized, Function, TemplateParams, Declaration, Variables);
+
+  EXPECT_EQ(dwarf::DW_TAG_subprogram, N->getTag());
+  EXPECT_EQ(Scope, N->getScope());
+  EXPECT_EQ(Name, N->getName());
+  EXPECT_EQ(LinkageName, N->getLinkageName());
+  EXPECT_EQ(File, N->getFile());
+  EXPECT_EQ(Line, N->getLine());
+  EXPECT_EQ(Type, N->getType());
+  EXPECT_EQ(IsLocalToUnit, N->isLocalToUnit());
+  EXPECT_EQ(IsDefinition, N->isDefinition());
+  EXPECT_EQ(ScopeLine, N->getScopeLine());
+  EXPECT_EQ(ContainingType, N->getContainingType());
+  EXPECT_EQ(Virtuality, N->getVirtuality());
+  EXPECT_EQ(VirtualIndex, N->getVirtualIndex());
+  EXPECT_EQ(Flags, N->getFlags());
+  EXPECT_EQ(IsOptimized, N->isOptimized());
+  EXPECT_EQ(Function, N->getFunction());
+  EXPECT_EQ(TemplateParams, N->getTemplateParams());
+  EXPECT_EQ(Declaration, N->getDeclaration());
+  EXPECT_EQ(Variables, N->getVariables());
+  EXPECT_EQ(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, Function, TemplateParams,
+                                 Declaration, Variables));
+
+  EXPECT_NE(N, MDSubprogram::get(Context, File, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, Function, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, "other", LinkageName, File,
+                                 Line, Type, IsLocalToUnit, IsDefinition,
+                                 ScopeLine, ContainingType, Virtuality,
+                                 VirtualIndex, Flags, IsOptimized, Function,
+                                 TemplateParams, Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, "other", File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, Function, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, Scope, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, Function, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File,
+                                 Line + 1, Type, IsLocalToUnit, IsDefinition,
+                                 ScopeLine, ContainingType, Virtuality,
+                                 VirtualIndex, Flags, IsOptimized, Function,
+                                 TemplateParams, Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Scope, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, Function, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, !IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, Function, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, !IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, Function, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition,
+                                 ScopeLine + 1, ContainingType, Virtuality,
+                                 VirtualIndex, Flags, IsOptimized, Function,
+                                 TemplateParams, Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 Type, Virtuality, VirtualIndex, Flags,
+                                 IsOptimized, Function, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality + 1, VirtualIndex,
+                                 Flags, IsOptimized, Function, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex + 1,
+                                 Flags, IsOptimized, Function, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 ~Flags, IsOptimized, Function, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, !IsOptimized, Function, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, Type, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, Function, Type,
+                                 Declaration, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, Function, TemplateParams,
+                                 Type, Variables));
+  EXPECT_NE(N, MDSubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, Function, TemplateParams,
+                                 Declaration, Type));
+
+  TempMDSubprogram Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(MDSubprogramTest, replaceFunction) {
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  StringRef Name = "name";
+  StringRef LinkageName = "linkage";
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  unsigned Line = 2;
+  Metadata *Type = MDTuple::getDistinct(Context, None);
+  bool IsLocalToUnit = false;
+  bool IsDefinition = true;
+  unsigned ScopeLine = 3;
+  Metadata *ContainingType = MDTuple::getDistinct(Context, None);
+  unsigned Virtuality = 4;
+  unsigned VirtualIndex = 5;
+  unsigned Flags = 6;
+  bool IsOptimized = false;
+  Metadata *TemplateParams = MDTuple::getDistinct(Context, None);
+  Metadata *Declaration = MDTuple::getDistinct(Context, None);
+  Metadata *Variables = MDTuple::getDistinct(Context, None);
+
+  auto *N = MDSubprogram::get(
+      Context, Scope, Name, LinkageName, File, Line, Type, IsLocalToUnit,
+      IsDefinition, ScopeLine, ContainingType, Virtuality, VirtualIndex, Flags,
+      IsOptimized, nullptr, TemplateParams, Declaration, Variables);
+
+  EXPECT_EQ(nullptr, N->getFunction());
+
+  std::unique_ptr<Function> F(
+      Function::Create(FunctionType::get(Type::getVoidTy(Context), false),
+                       GlobalValue::ExternalLinkage));
+  N->replaceFunction(F.get());
+  EXPECT_EQ(ConstantAsMetadata::get(F.get()), N->getFunction());
+
+  N->replaceFunction(nullptr);
+  EXPECT_EQ(nullptr, N->getFunction());
+}
+
+typedef MetadataTest MDLexicalBlockTest;
+
+TEST_F(MDLexicalBlockTest, get) {
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  unsigned Line = 5;
+  unsigned Column = 8;
+
+  auto *N = MDLexicalBlock::get(Context, Scope, File, Line, Column);
+
+  EXPECT_EQ(dwarf::DW_TAG_lexical_block, N->getTag());
+  EXPECT_EQ(Scope, N->getScope());
+  EXPECT_EQ(File, N->getFile());
+  EXPECT_EQ(Line, N->getLine());
+  EXPECT_EQ(Column, N->getColumn());
+  EXPECT_EQ(N, MDLexicalBlock::get(Context, Scope, File, Line, Column));
+
+  EXPECT_NE(N, MDLexicalBlock::get(Context, File, File, Line, Column));
+  EXPECT_NE(N, MDLexicalBlock::get(Context, Scope, Scope, Line, Column));
+  EXPECT_NE(N, MDLexicalBlock::get(Context, Scope, File, Line + 1, Column));
+  EXPECT_NE(N, MDLexicalBlock::get(Context, Scope, File, Line, Column + 1));
+
+  TempMDLexicalBlock Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest MDLexicalBlockFileTest;
+
+TEST_F(MDLexicalBlockFileTest, get) {
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  unsigned Discriminator = 5;
+
+  auto *N = MDLexicalBlockFile::get(Context, Scope, File, Discriminator);
+
+  EXPECT_EQ(dwarf::DW_TAG_lexical_block, N->getTag());
+  EXPECT_EQ(Scope, N->getScope());
+  EXPECT_EQ(File, N->getFile());
+  EXPECT_EQ(Discriminator, N->getDiscriminator());
+  EXPECT_EQ(N, MDLexicalBlockFile::get(Context, Scope, File, Discriminator));
+
+  EXPECT_NE(N, MDLexicalBlockFile::get(Context, File, File, Discriminator));
+  EXPECT_NE(N, MDLexicalBlockFile::get(Context, Scope, Scope, Discriminator));
+  EXPECT_NE(N,
+            MDLexicalBlockFile::get(Context, Scope, File, Discriminator + 1));
+
+  TempMDLexicalBlockFile Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest MDNamespaceTest;
+
+TEST_F(MDNamespaceTest, get) {
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  StringRef Name = "namespace";
+  unsigned Line = 5;
+
+  auto *N = MDNamespace::get(Context, Scope, File, Name, Line);
+
+  EXPECT_EQ(dwarf::DW_TAG_namespace, N->getTag());
+  EXPECT_EQ(Scope, N->getScope());
+  EXPECT_EQ(File, N->getFile());
+  EXPECT_EQ(Name, N->getName());
+  EXPECT_EQ(Line, N->getLine());
+  EXPECT_EQ(N, MDNamespace::get(Context, Scope, File, Name, Line));
+
+  EXPECT_NE(N, MDNamespace::get(Context, File, File, Name, Line));
+  EXPECT_NE(N, MDNamespace::get(Context, Scope, Scope, Name, Line));
+  EXPECT_NE(N, MDNamespace::get(Context, Scope, File, "other", Line));
+  EXPECT_NE(N, MDNamespace::get(Context, Scope, File, Name, Line + 1));
+
+  TempMDNamespace Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest MDTemplateTypeParameterTest;
+
+TEST_F(MDTemplateTypeParameterTest, get) {
+  StringRef Name = "template";
+  Metadata *Type = MDTuple::getDistinct(Context, None);
+  Metadata *Other = MDTuple::getDistinct(Context, None);
+
+  auto *N = MDTemplateTypeParameter::get(Context, Name, Type);
+
+  EXPECT_EQ(dwarf::DW_TAG_template_type_parameter, N->getTag());
+  EXPECT_EQ(Name, N->getName());
+  EXPECT_EQ(Type, N->getType());
+  EXPECT_EQ(N, MDTemplateTypeParameter::get(Context, Name, Type));
+
+  EXPECT_NE(N, MDTemplateTypeParameter::get(Context, "other", Type));
+  EXPECT_NE(N, MDTemplateTypeParameter::get(Context, Name, Other));
+
+  TempMDTemplateTypeParameter Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest MDTemplateValueParameterTest;
+
+TEST_F(MDTemplateValueParameterTest, get) {
+  unsigned Tag = dwarf::DW_TAG_template_value_parameter;
+  StringRef Name = "template";
+  Metadata *Type = MDTuple::getDistinct(Context, None);
+  Metadata *Value = MDTuple::getDistinct(Context, None);
+  Metadata *Other = MDTuple::getDistinct(Context, None);
+
+  auto *N = MDTemplateValueParameter::get(Context, Tag, Name, Type, Value);
+  EXPECT_EQ(Tag, N->getTag());
+  EXPECT_EQ(Name, N->getName());
+  EXPECT_EQ(Type, N->getType());
+  EXPECT_EQ(Value, N->getValue());
+  EXPECT_EQ(N, MDTemplateValueParameter::get(Context, Tag, Name, Type, Value));
+
+  EXPECT_NE(N, MDTemplateValueParameter::get(
+                   Context, dwarf::DW_TAG_GNU_template_template_param, Name,
+                   Type, Value));
+  EXPECT_NE(N, MDTemplateValueParameter::get(Context, Tag,  "other", Type,
+                                             Value));
+  EXPECT_NE(N, MDTemplateValueParameter::get(Context, Tag,  Name, Other,
+                                             Value));
+  EXPECT_NE(N, MDTemplateValueParameter::get(Context, Tag, Name, Type, Other));
+
+  TempMDTemplateValueParameter Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest MDGlobalVariableTest;
+
+TEST_F(MDGlobalVariableTest, get) {
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  StringRef Name = "name";
+  StringRef LinkageName = "linkage";
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  unsigned Line = 5;
+  Metadata *Type = MDTuple::getDistinct(Context, None);
+  bool IsLocalToUnit = false;
+  bool IsDefinition = true;
+  Metadata *Variable = MDTuple::getDistinct(Context, None);
+  Metadata *StaticDataMemberDeclaration = MDTuple::getDistinct(Context, None);
+
+  auto *N = MDGlobalVariable::get(Context, Scope, Name, LinkageName, File, Line,
+                                  Type, IsLocalToUnit, IsDefinition, Variable,
+                                  StaticDataMemberDeclaration);
+  EXPECT_EQ(dwarf::DW_TAG_variable, N->getTag());
+  EXPECT_EQ(Scope, N->getScope());
+  EXPECT_EQ(Name, N->getName());
+  EXPECT_EQ(LinkageName, N->getLinkageName());
+  EXPECT_EQ(File, N->getFile());
+  EXPECT_EQ(Line, N->getLine());
+  EXPECT_EQ(Type, N->getType());
+  EXPECT_EQ(IsLocalToUnit, N->isLocalToUnit());
+  EXPECT_EQ(IsDefinition, N->isDefinition());
+  EXPECT_EQ(Variable, N->getVariable());
+  EXPECT_EQ(StaticDataMemberDeclaration, N->getStaticDataMemberDeclaration());
+  EXPECT_EQ(N, MDGlobalVariable::get(Context, Scope, Name, LinkageName, File,
+                                     Line, Type, IsLocalToUnit, IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+
+  EXPECT_NE(N, MDGlobalVariable::get(Context, File, Name, LinkageName, File,
+                                     Line, Type, IsLocalToUnit, IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N, MDGlobalVariable::get(Context, Scope, "other", LinkageName, File,
+                                     Line, Type, IsLocalToUnit, IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N, MDGlobalVariable::get(Context, Scope, Name, "other", File, Line,
+                                     Type, IsLocalToUnit, IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N, MDGlobalVariable::get(Context, Scope, Name, LinkageName, Scope,
+                                     Line, Type, IsLocalToUnit, IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N,
+            MDGlobalVariable::get(Context, Scope, Name, LinkageName, File,
+                                  Line + 1, Type, IsLocalToUnit, IsDefinition,
+                                  Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N, MDGlobalVariable::get(Context, Scope, Name, LinkageName, File,
+                                     Line, Scope, IsLocalToUnit, IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N, MDGlobalVariable::get(Context, Scope, Name, LinkageName, File,
+                                     Line, Type, !IsLocalToUnit, IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N, MDGlobalVariable::get(Context, Scope, Name, LinkageName, File,
+                                     Line, Type, IsLocalToUnit, !IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N, MDGlobalVariable::get(Context, Scope, Name, LinkageName, File,
+                                     Line, Type, IsLocalToUnit, IsDefinition,
+                                     Type, StaticDataMemberDeclaration));
+  EXPECT_NE(N, MDGlobalVariable::get(Context, Scope, Name, LinkageName, File,
+                                     Line, Type, IsLocalToUnit, IsDefinition,
+                                     Variable, Type));
+
+  TempMDGlobalVariable Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest MDLocalVariableTest;
+
+TEST_F(MDLocalVariableTest, get) {
+  unsigned Tag = dwarf::DW_TAG_arg_variable;
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  StringRef Name = "name";
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  unsigned Line = 5;
+  Metadata *Type = MDTuple::getDistinct(Context, None);
+  unsigned Arg = 6;
+  unsigned Flags = 7;
+  Metadata *InlinedAt = MDTuple::getDistinct(Context, None);
+
+  auto *N = MDLocalVariable::get(Context, Tag, Scope, Name, File, Line, Type,
+                                 Arg, Flags, InlinedAt);
+  EXPECT_EQ(Tag, N->getTag());
+  EXPECT_EQ(Scope, N->getScope());
+  EXPECT_EQ(Name, N->getName());
+  EXPECT_EQ(File, N->getFile());
+  EXPECT_EQ(Line, N->getLine());
+  EXPECT_EQ(Type, N->getType());
+  EXPECT_EQ(Arg, N->getArg());
+  EXPECT_EQ(Flags, N->getFlags());
+  EXPECT_EQ(InlinedAt, N->getInlinedAt());
+  EXPECT_EQ(N, MDLocalVariable::get(Context, Tag, Scope, Name, File, Line, Type,
+                                    Arg, Flags, InlinedAt));
+
+  EXPECT_NE(N, MDLocalVariable::get(Context, dwarf::DW_TAG_auto_variable, Scope,
+                                    Name, File, Line, Type, Arg, Flags,
+                                    InlinedAt));
+  EXPECT_NE(N, MDLocalVariable::get(Context, Tag, File, Name, File, Line,
+                                    Type, Arg, Flags, InlinedAt));
+  EXPECT_NE(N, MDLocalVariable::get(Context, Tag, Scope, "other", File, Line,
+                                    Type, Arg, Flags, InlinedAt));
+  EXPECT_NE(N, MDLocalVariable::get(Context, Tag, Scope, Name, Scope, Line,
+                                    Type, Arg, Flags, InlinedAt));
+  EXPECT_NE(N, MDLocalVariable::get(Context, Tag, Scope, Name, File, Line + 1,
+                                    Type, Arg, Flags, InlinedAt));
+  EXPECT_NE(N, MDLocalVariable::get(Context, Tag, Scope, Name, File, Line,
+                                    Scope, Arg, Flags, InlinedAt));
+  EXPECT_NE(N, MDLocalVariable::get(Context, Tag, Scope, Name, File, Line, Type,
+                                    Arg + 1, Flags, InlinedAt));
+  EXPECT_NE(N, MDLocalVariable::get(Context, Tag, Scope, Name, File, Line, Type,
+                                    Arg, ~Flags, InlinedAt));
+  EXPECT_NE(N, MDLocalVariable::get(Context, Tag, Scope, Name, File, Line, Type,
+                                    Arg, Flags, Scope));
+
+  TempMDLocalVariable Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest MDExpressionTest;
+
+TEST_F(MDExpressionTest, get) {
+  uint64_t Elements[] = {2, 6, 9, 78, 0};
+  auto *N = MDExpression::get(Context, Elements);
+  EXPECT_EQ(makeArrayRef(Elements), N->getElements());
+  EXPECT_EQ(N, MDExpression::get(Context, Elements));
+
+  EXPECT_EQ(5u, N->getNumElements());
+  EXPECT_EQ(2u, N->getElement(0));
+  EXPECT_EQ(6u, N->getElement(1));
+  EXPECT_EQ(9u, N->getElement(2));
+  EXPECT_EQ(78u, N->getElement(3));
+  EXPECT_EQ(0u, N->getElement(4));
+
+  TempMDExpression Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(MDExpressionTest, isValid) {
+#define EXPECT_VALID(...)                                                      \
+  do {                                                                         \
+    uint64_t Elements[] = {__VA_ARGS__};                                       \
+    EXPECT_TRUE(MDExpression::get(Context, Elements)->isValid());              \
+  } while (false)
+#define EXPECT_INVALID(...)                                                    \
+  do {                                                                         \
+    uint64_t Elements[] = {__VA_ARGS__};                                       \
+    EXPECT_FALSE(MDExpression::get(Context, Elements)->isValid());             \
+  } while (false)
+
+  // Empty expression should be valid.
+  EXPECT_TRUE(MDExpression::get(Context, None));
+
+  // Valid constructions.
+  EXPECT_VALID(dwarf::DW_OP_plus, 6);
+  EXPECT_VALID(dwarf::DW_OP_deref);
+  EXPECT_VALID(dwarf::DW_OP_bit_piece, 3, 7);
+  EXPECT_VALID(dwarf::DW_OP_plus, 6, dwarf::DW_OP_deref);
+  EXPECT_VALID(dwarf::DW_OP_deref, dwarf::DW_OP_plus, 6);
+  EXPECT_VALID(dwarf::DW_OP_deref, dwarf::DW_OP_bit_piece, 3, 7);
+  EXPECT_VALID(dwarf::DW_OP_deref, dwarf::DW_OP_plus, 6, dwarf::DW_OP_bit_piece, 3, 7);
+
+  // Invalid constructions.
+  EXPECT_INVALID(~0u);
+  EXPECT_INVALID(dwarf::DW_OP_plus);
+  EXPECT_INVALID(dwarf::DW_OP_bit_piece);
+  EXPECT_INVALID(dwarf::DW_OP_bit_piece, 3);
+  EXPECT_INVALID(dwarf::DW_OP_bit_piece, 3, 7, dwarf::DW_OP_plus, 3);
+  EXPECT_INVALID(dwarf::DW_OP_bit_piece, 3, 7, dwarf::DW_OP_deref);
+
+#undef EXPECT_VALID
+#undef EXPECT_INVALID
+}
+
+typedef MetadataTest MDObjCPropertyTest;
+
+TEST_F(MDObjCPropertyTest, get) {
+  StringRef Name = "name";
+  Metadata *File = MDTuple::getDistinct(Context, None);
+  unsigned Line = 5;
+  StringRef GetterName = "getter";
+  StringRef SetterName = "setter";
+  unsigned Attributes = 7;
+  Metadata *Type = MDTuple::getDistinct(Context, None);
+
+  auto *N = MDObjCProperty::get(Context, Name, File, Line, GetterName,
+                                SetterName, Attributes, Type);
+
+  EXPECT_EQ(dwarf::DW_TAG_APPLE_property, N->getTag());
+  EXPECT_EQ(Name, N->getName());
+  EXPECT_EQ(File, N->getFile());
+  EXPECT_EQ(Line, N->getLine());
+  EXPECT_EQ(GetterName, N->getGetterName());
+  EXPECT_EQ(SetterName, N->getSetterName());
+  EXPECT_EQ(Attributes, N->getAttributes());
+  EXPECT_EQ(Type, N->getType());
+  EXPECT_EQ(N, MDObjCProperty::get(Context, Name, File, Line, GetterName,
+                                   SetterName, Attributes, Type));
+
+  EXPECT_NE(N, MDObjCProperty::get(Context, "other", File, Line, GetterName,
+                                   SetterName, Attributes, Type));
+  EXPECT_NE(N, MDObjCProperty::get(Context, Name, Type, Line, GetterName,
+                                   SetterName, Attributes, Type));
+  EXPECT_NE(N, MDObjCProperty::get(Context, Name, File, Line + 1, GetterName,
+                                   SetterName, Attributes, Type));
+  EXPECT_NE(N, MDObjCProperty::get(Context, Name, File, Line, "other",
+                                   SetterName, Attributes, Type));
+  EXPECT_NE(N, MDObjCProperty::get(Context, Name, File, Line, GetterName,
+                                   "other", Attributes, Type));
+  EXPECT_NE(N, MDObjCProperty::get(Context, Name, File, Line, GetterName,
+                                   SetterName, Attributes + 1, Type));
+  EXPECT_NE(N, MDObjCProperty::get(Context, Name, File, Line, GetterName,
+                                   SetterName, Attributes, File));
+
+  TempMDObjCProperty Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest MDImportedEntityTest;
+
+TEST_F(MDImportedEntityTest, get) {
+  unsigned Tag = dwarf::DW_TAG_imported_module;
+  Metadata *Scope = MDTuple::getDistinct(Context, None);
+  Metadata *Entity = MDTuple::getDistinct(Context, None);
+  unsigned Line = 5;
+  StringRef Name = "name";
+
+  auto *N = MDImportedEntity::get(Context, Tag, Scope, Entity, Line, Name);
+
+  EXPECT_EQ(Tag, N->getTag());
+  EXPECT_EQ(Scope, N->getScope());
+  EXPECT_EQ(Entity, N->getEntity());
+  EXPECT_EQ(Line, N->getLine());
+  EXPECT_EQ(Name, N->getName());
+  EXPECT_EQ(N, MDImportedEntity::get(Context, Tag, Scope, Entity, Line, Name));
+
+  EXPECT_NE(N,
+            MDImportedEntity::get(Context, dwarf::DW_TAG_imported_declaration,
+                                  Scope, Entity, Line, Name));
+  EXPECT_NE(N, MDImportedEntity::get(Context, Tag, Entity, Entity, Line, Name));
+  EXPECT_NE(N, MDImportedEntity::get(Context, Tag, Scope, Scope, Line, Name));
+  EXPECT_NE(N,
+            MDImportedEntity::get(Context, Tag, Scope, Entity, Line + 1, Name));
+  EXPECT_NE(N,
+            MDImportedEntity::get(Context, Tag, Scope, Entity, Line, "other"));
+
+  TempMDImportedEntity Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest MetadataAsValueTest;
+
+TEST_F(MetadataAsValueTest, MDNode) {
+  MDNode *N = MDNode::get(Context, None);
+  auto *V = MetadataAsValue::get(Context, N);
+  EXPECT_TRUE(V->getType()->isMetadataTy());
+  EXPECT_EQ(N, V->getMetadata());
+
+  auto *V2 = MetadataAsValue::get(Context, N);
+  EXPECT_EQ(V, V2);
+}
+
+TEST_F(MetadataAsValueTest, MDNodeMDNode) {
+  MDNode *N = MDNode::get(Context, None);
+  Metadata *Ops[] = {N};
+  MDNode *N2 = MDNode::get(Context, Ops);
+  auto *V = MetadataAsValue::get(Context, N2);
+  EXPECT_TRUE(V->getType()->isMetadataTy());
+  EXPECT_EQ(N2, V->getMetadata());
+
+  auto *V2 = MetadataAsValue::get(Context, N2);
+  EXPECT_EQ(V, V2);
+
+  auto *V3 = MetadataAsValue::get(Context, N);
+  EXPECT_TRUE(V3->getType()->isMetadataTy());
+  EXPECT_NE(V, V3);
+  EXPECT_EQ(N, V3->getMetadata());
+}
+
+TEST_F(MetadataAsValueTest, MDNodeConstant) {
+  auto *C = ConstantInt::getTrue(Context);
+  auto *MD = ConstantAsMetadata::get(C);
+  Metadata *Ops[] = {MD};
+  auto *N = MDNode::get(Context, Ops);
+
+  auto *V = MetadataAsValue::get(Context, MD);
+  EXPECT_TRUE(V->getType()->isMetadataTy());
+  EXPECT_EQ(MD, V->getMetadata());
+
+  auto *V2 = MetadataAsValue::get(Context, N);
+  EXPECT_EQ(MD, V2->getMetadata());
+  EXPECT_EQ(V, V2);
+}
+
+typedef MetadataTest ValueAsMetadataTest;
+
+TEST_F(ValueAsMetadataTest, UpdatesOnRAUW) {
+  Type *Ty = Type::getInt1PtrTy(Context);
+  std::unique_ptr<GlobalVariable> GV0(
+      new GlobalVariable(Ty, false, GlobalValue::ExternalLinkage));
+  auto *MD = ValueAsMetadata::get(GV0.get());
+  EXPECT_TRUE(MD->getValue() == GV0.get());
+  ASSERT_TRUE(GV0->use_empty());
+
+  std::unique_ptr<GlobalVariable> GV1(
+      new GlobalVariable(Ty, false, GlobalValue::ExternalLinkage));
+  GV0->replaceAllUsesWith(GV1.get());
+  EXPECT_TRUE(MD->getValue() == GV1.get());
+}
+
+TEST_F(ValueAsMetadataTest, CollidingDoubleUpdates) {
+  // Create a constant.
+  ConstantAsMetadata *CI = ConstantAsMetadata::get(
+      ConstantInt::get(getGlobalContext(), APInt(8, 0)));
+
+  // Create a temporary to prevent nodes from resolving.
+  auto Temp = MDTuple::getTemporary(Context, None);
+
+  // When the first operand of N1 gets reset to nullptr, it'll collide with N2.
+  Metadata *Ops1[] = {CI, CI, Temp.get()};
+  Metadata *Ops2[] = {nullptr, CI, Temp.get()};
+
+  auto *N1 = MDTuple::get(Context, Ops1);
+  auto *N2 = MDTuple::get(Context, Ops2);
+  ASSERT_NE(N1, N2);
+
+  // Tell metadata that the constant is getting deleted.
+  //
+  // After this, N1 will be invalid, so don't touch it.
+  ValueAsMetadata::handleDeletion(CI->getValue());
+  EXPECT_EQ(nullptr, N2->getOperand(0));
+  EXPECT_EQ(nullptr, N2->getOperand(1));
+  EXPECT_EQ(Temp.get(), N2->getOperand(2));
+
+  // Clean up Temp for teardown.
+  Temp->replaceAllUsesWith(nullptr);
+}
+
+typedef MetadataTest TrackingMDRefTest;
+
+TEST_F(TrackingMDRefTest, UpdatesOnRAUW) {
+  Type *Ty = Type::getInt1PtrTy(Context);
+  std::unique_ptr<GlobalVariable> GV0(
+      new GlobalVariable(Ty, false, GlobalValue::ExternalLinkage));
+  TypedTrackingMDRef<ValueAsMetadata> MD(ValueAsMetadata::get(GV0.get()));
+  EXPECT_TRUE(MD->getValue() == GV0.get());
+  ASSERT_TRUE(GV0->use_empty());
+
+  std::unique_ptr<GlobalVariable> GV1(
+      new GlobalVariable(Ty, false, GlobalValue::ExternalLinkage));
+  GV0->replaceAllUsesWith(GV1.get());
+  EXPECT_TRUE(MD->getValue() == GV1.get());
+
+  // Reset it, so we don't inadvertently test deletion.
+  MD.reset();
+}
+
+TEST_F(TrackingMDRefTest, UpdatesOnDeletion) {
+  Type *Ty = Type::getInt1PtrTy(Context);
+  std::unique_ptr<GlobalVariable> GV(
+      new GlobalVariable(Ty, false, GlobalValue::ExternalLinkage));
+  TypedTrackingMDRef<ValueAsMetadata> MD(ValueAsMetadata::get(GV.get()));
+  EXPECT_TRUE(MD->getValue() == GV.get());
+  ASSERT_TRUE(GV->use_empty());
+
+  GV.reset();
+  EXPECT_TRUE(!MD);
+}
+
 TEST(NamedMDNodeTest, Search) {
   LLVMContext Context;
-  Constant *C = ConstantInt::get(Type::getInt32Ty(Context), 1);
-  Constant *C2 = ConstantInt::get(Type::getInt32Ty(Context), 2);
+  ConstantAsMetadata *C =
+      ConstantAsMetadata::get(ConstantInt::get(Type::getInt32Ty(Context), 1));
+  ConstantAsMetadata *C2 =
+      ConstantAsMetadata::get(ConstantInt::get(Type::getInt32Ty(Context), 2));
 
-  Value *const V = C;
-  Value *const V2 = C2;
+  Metadata *const V = C;
+  Metadata *const V2 = C2;
   MDNode *n = MDNode::get(Context, V);
   MDNode *n2 = MDNode::get(Context, V2);