[ThinLTO] Support cloning of temporary DILocation metadata
[oota-llvm.git] / unittests / IR / MetadataTest.cpp
index ef071b38a7bcb6198677dae26ddd48d741d410ef..8f346f53a2d22b72790d74726e071c6473a68484 100644 (file)
@@ -1,4 +1,4 @@
-//===- llvm/unittest/IR/Metadata.cpp - Metadata unit tests ----------------===//
+//===- unittests/IR/MetadataTest.cpp - Metadata unit tests ----------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/IR/Metadata.h"
+#include "llvm/ADT/STLExtras.h"
 #include "llvm/IR/Constants.h"
+#include "llvm/IR/DebugInfo.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/ModuleSlotTracker.h"
 #include "llvm/IR/Type.h"
+#include "llvm/IR/Verifier.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 {
+public:
+  MetadataTest() : M("test", Context), Counter(0) {}
+
 protected:
   LLVMContext Context;
+  Module M;
+  int Counter;
+
   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);
   }
+
+  MDTuple *getTuple() { return MDTuple::getDistinct(Context, None); }
+  DISubroutineType *getSubroutineType() {
+    return DISubroutineType::getDistinct(Context, 0, getNode(nullptr));
+  }
+  DISubprogram *getSubprogram() {
+    return DISubprogram::getDistinct(Context, nullptr, "", "", nullptr, 0,
+                                     nullptr, false, false, 0, nullptr, 0, 0, 0,
+                                     0);
+  }
+  DIScopeRef getSubprogramRef() { return getSubprogram()->getRef(); }
+  DIFile *getFile() {
+    return DIFile::getDistinct(Context, "file.c", "/path/to/dir");
+  }
+  DITypeRef getBasicType(StringRef Name) {
+    return DIBasicType::get(Context, dwarf::DW_TAG_unspecified_type, Name)
+        ->getRef();
+  }
+  DITypeRef getDerivedType() {
+    return DIDerivedType::getDistinct(Context, dwarf::DW_TAG_pointer_type, "",
+                                      nullptr, 0, nullptr,
+                                      getBasicType("basictype"), 1, 2, 0, 0)
+        ->getRef();
+  }
+  Constant *getConstant() {
+    return ConstantInt::get(Type::getInt32Ty(Context), Counter++);
+  }
+  ConstantAsMetadata *getConstantAsMetadata() {
+    return ConstantAsMetadata::get(getConstant());
+  }
+  DITypeRef getCompositeType() {
+    return DICompositeType::getDistinct(
+               Context, dwarf::DW_TAG_structure_type, "", nullptr, 0, nullptr,
+               nullptr, 32, 32, 0, 0, nullptr, 0, nullptr, nullptr, "")
+        ->getRef();
+  }
+  Function *getFunction(StringRef Name) {
+    return cast<Function>(M.getOrInsertFunction(
+        Name, FunctionType::get(Type::getVoidTy(Context), None, false)));
+  }
 };
 typedef MetadataTest MDStringTest;
 
@@ -133,11 +222,10 @@ TEST_F(MDNodeTest, SelfReference) {
   // !0 = !{!0}
   // !1 = !{!0}
   {
-    MDNode *Temp = MDNode::getTemporary(Context, None);
-    Metadata *Args[] = {Temp};
+    auto Temp = MDNode::getTemporary(Context, None);
+    Metadata *Args[] = {Temp.get()};
     MDNode *Self = MDNode::get(Context, Args);
     Self->replaceOperandWith(0, Self);
-    MDNode::deleteTemporary(Temp);
     ASSERT_EQ(Self, Self->getOperand(0));
 
     // Self-references should be distinct, so MDNode::get() should grab a
@@ -152,11 +240,10 @@ TEST_F(MDNodeTest, SelfReference) {
   // !0 = !{!0, !{}}
   // !1 = !{!0, !{}}
   {
-    MDNode *Temp = MDNode::getTemporary(Context, None);
-    Metadata *Args[] = {Temp, MDNode::get(Context, None)};
+    auto Temp = MDNode::getTemporary(Context, None);
+    Metadata *Args[] = {Temp.get(), MDNode::get(Context, None)};
     MDNode *Self = MDNode::get(Context, Args);
     Self->replaceOperandWith(0, Self);
-    MDNode::deleteTemporary(Temp);
     ASSERT_EQ(Self, Self->getOperand(0));
 
     // Self-references should be distinct, so MDNode::get() should grab a
@@ -182,7 +269,7 @@ TEST_F(MDNodeTest, Print) {
   std::string Expected;
   {
     raw_string_ostream OS(Expected);
-    OS << "!{";
+    OS << "<" << (void *)N << "> = !{";
     C->printAsOperand(OS);
     OS << ", ";
     S->printAsOperand(OS);
@@ -190,7 +277,7 @@ TEST_F(MDNodeTest, Print) {
     MDNode *Nodes[] = {N0, N1, N2};
     for (auto *Node : Nodes)
       OS << ", <" << (void *)Node << ">";
-    OS << "}\n";
+    OS << "}";
   }
 
   std::string Actual;
@@ -202,6 +289,117 @@ TEST_F(MDNodeTest, Print) {
   EXPECT_EQ(Expected, Actual);
 }
 
+#define EXPECT_PRINTER_EQ(EXPECTED, PRINT)                                     \
+  do {                                                                         \
+    std::string Actual_;                                                       \
+    raw_string_ostream OS(Actual_);                                            \
+    PRINT;                                                                     \
+    OS.flush();                                                                \
+    std::string Expected_(EXPECTED);                                           \
+    EXPECT_EQ(Expected_, Actual_);                                             \
+  } while (false)
+
+TEST_F(MDNodeTest, PrintTemporary) {
+  MDNode *Arg = getNode();
+  TempMDNode Temp = MDNode::getTemporary(Context, Arg);
+  MDNode *N = getNode(Temp.get());
+  Module M("test", Context);
+  NamedMDNode *NMD = M.getOrInsertNamedMetadata("named");
+  NMD->addOperand(N);
+
+  EXPECT_PRINTER_EQ("!0 = !{!1}", N->print(OS, &M));
+  EXPECT_PRINTER_EQ("!1 = <temporary!> !{!2}", Temp->print(OS, &M));
+  EXPECT_PRINTER_EQ("!2 = !{}", Arg->print(OS, &M));
+
+  // Cleanup.
+  Temp->replaceAllUsesWith(Arg);
+}
+
+TEST_F(MDNodeTest, PrintFromModule) {
+  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);
+  Module M("test", Context);
+  NamedMDNode *NMD = M.getOrInsertNamedMetadata("named");
+  NMD->addOperand(N);
+
+  std::string Expected;
+  {
+    raw_string_ostream OS(Expected);
+    OS << "!0 = !{";
+    C->printAsOperand(OS);
+    OS << ", ";
+    S->printAsOperand(OS);
+    OS << ", null, !1, !2, !3}";
+  }
+
+  EXPECT_PRINTER_EQ(Expected, N->print(OS, &M));
+}
+
+TEST_F(MDNodeTest, PrintFromFunction) {
+  Module M("test", Context);
+  auto *FTy = FunctionType::get(Type::getVoidTy(Context), false);
+  auto *F0 = Function::Create(FTy, GlobalValue::ExternalLinkage, "F0", &M);
+  auto *F1 = Function::Create(FTy, GlobalValue::ExternalLinkage, "F1", &M);
+  auto *BB0 = BasicBlock::Create(Context, "entry", F0);
+  auto *BB1 = BasicBlock::Create(Context, "entry", F1);
+  auto *R0 = ReturnInst::Create(Context, BB0);
+  auto *R1 = ReturnInst::Create(Context, BB1);
+  auto *N0 = MDNode::getDistinct(Context, None);
+  auto *N1 = MDNode::getDistinct(Context, None);
+  R0->setMetadata("md", N0);
+  R1->setMetadata("md", N1);
+
+  EXPECT_PRINTER_EQ("!0 = distinct !{}", N0->print(OS, &M));
+  EXPECT_PRINTER_EQ("!1 = distinct !{}", N1->print(OS, &M));
+
+  ModuleSlotTracker MST(&M);
+  EXPECT_PRINTER_EQ("!0 = distinct !{}", N0->print(OS, MST));
+  EXPECT_PRINTER_EQ("!1 = distinct !{}", N1->print(OS, MST));
+}
+
+TEST_F(MDNodeTest, PrintFromMetadataAsValue) {
+  Module M("test", Context);
+
+  auto *Intrinsic =
+      Function::Create(FunctionType::get(Type::getVoidTy(Context),
+                                         Type::getMetadataTy(Context), false),
+                       GlobalValue::ExternalLinkage, "llvm.intrinsic", &M);
+
+  auto *FTy = FunctionType::get(Type::getVoidTy(Context), false);
+  auto *F0 = Function::Create(FTy, GlobalValue::ExternalLinkage, "F0", &M);
+  auto *F1 = Function::Create(FTy, GlobalValue::ExternalLinkage, "F1", &M);
+  auto *BB0 = BasicBlock::Create(Context, "entry", F0);
+  auto *BB1 = BasicBlock::Create(Context, "entry", F1);
+  auto *N0 = MDNode::getDistinct(Context, None);
+  auto *N1 = MDNode::getDistinct(Context, None);
+  auto *MAV0 = MetadataAsValue::get(Context, N0);
+  auto *MAV1 = MetadataAsValue::get(Context, N1);
+  CallInst::Create(Intrinsic, MAV0, "", BB0);
+  CallInst::Create(Intrinsic, MAV1, "", BB1);
+
+  EXPECT_PRINTER_EQ("!0 = distinct !{}", MAV0->print(OS));
+  EXPECT_PRINTER_EQ("!1 = distinct !{}", MAV1->print(OS));
+  EXPECT_PRINTER_EQ("!0", MAV0->printAsOperand(OS, false));
+  EXPECT_PRINTER_EQ("!1", MAV1->printAsOperand(OS, false));
+  EXPECT_PRINTER_EQ("metadata !0", MAV0->printAsOperand(OS, true));
+  EXPECT_PRINTER_EQ("metadata !1", MAV1->printAsOperand(OS, true));
+
+  ModuleSlotTracker MST(&M);
+  EXPECT_PRINTER_EQ("!0 = distinct !{}", MAV0->print(OS, MST));
+  EXPECT_PRINTER_EQ("!1 = distinct !{}", MAV1->print(OS, MST));
+  EXPECT_PRINTER_EQ("!0", MAV0->printAsOperand(OS, false, MST));
+  EXPECT_PRINTER_EQ("!1", MAV1->printAsOperand(OS, false, MST));
+  EXPECT_PRINTER_EQ("metadata !0", MAV0->printAsOperand(OS, true, MST));
+  EXPECT_PRINTER_EQ("metadata !1", MAV1->printAsOperand(OS, true, MST));
+}
+#undef EXPECT_PRINTER_EQ
+
 TEST_F(MDNodeTest, NullOperand) {
   // metadata !{}
   MDNode *Empty = MDNode::get(Context, None);
@@ -222,6 +420,1574 @@ TEST_F(MDNodeTest, NullOperand) {
   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, replaceWithUniquedResolvingOperand) {
+  // temp !{}
+  MDTuple *Op = MDTuple::getTemporary(Context, None).release();
+  EXPECT_FALSE(Op->isResolved());
+
+  // temp !{temp !{}}
+  Metadata *Ops[] = {Op};
+  MDTuple *N = MDTuple::getTemporary(Context, Ops).release();
+  EXPECT_FALSE(N->isResolved());
+
+  // temp !{temp !{}} => !{temp !{}}
+  ASSERT_EQ(N, MDNode::replaceWithUniqued(TempMDTuple(N)));
+  EXPECT_FALSE(N->isResolved());
+
+  // !{temp !{}} => !{!{}}
+  ASSERT_EQ(Op, MDNode::replaceWithUniqued(TempMDTuple(Op)));
+  EXPECT_TRUE(Op->isResolved());
+  EXPECT_TRUE(N->isResolved());
+}
+
+TEST_F(MDNodeTest, replaceWithUniquedChangingOperand) {
+  // i1* @GV
+  Type *Ty = Type::getInt1PtrTy(Context);
+  std::unique_ptr<GlobalVariable> GV(
+      new GlobalVariable(Ty, false, GlobalValue::ExternalLinkage));
+  ConstantAsMetadata *Op = ConstantAsMetadata::get(GV.get());
+
+  // temp !{i1* @GV}
+  Metadata *Ops[] = {Op};
+  MDTuple *N = MDTuple::getTemporary(Context, Ops).release();
+
+  // temp !{i1* @GV} => !{i1* @GV}
+  ASSERT_EQ(N, MDNode::replaceWithUniqued(TempMDTuple(N)));
+  ASSERT_TRUE(N->isUniqued());
+
+  // !{i1* @GV} => !{null}
+  GV.reset();
+  ASSERT_TRUE(N->isUniqued());
+  Metadata *NullOps[] = {nullptr};
+  ASSERT_EQ(N, MDTuple::get(Context, NullOps));
+}
+
+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 DILocationTest;
+
+TEST_F(DILocationTest, Overflow) {
+  DISubprogram *N = getSubprogram();
+  {
+    DILocation *L = DILocation::get(Context, 2, 7, N);
+    EXPECT_EQ(2u, L->getLine());
+    EXPECT_EQ(7u, L->getColumn());
+  }
+  unsigned U16 = 1u << 16;
+  {
+    DILocation *L = DILocation::get(Context, UINT32_MAX, U16 - 1, N);
+    EXPECT_EQ(UINT32_MAX, L->getLine());
+    EXPECT_EQ(U16 - 1, L->getColumn());
+  }
+  {
+    DILocation *L = DILocation::get(Context, UINT32_MAX, U16, N);
+    EXPECT_EQ(UINT32_MAX, L->getLine());
+    EXPECT_EQ(0u, L->getColumn());
+  }
+  {
+    DILocation *L = DILocation::get(Context, UINT32_MAX, U16 + 1, N);
+    EXPECT_EQ(UINT32_MAX, L->getLine());
+    EXPECT_EQ(0u, L->getColumn());
+  }
+}
+
+TEST_F(DILocationTest, getDistinct) {
+  MDNode *N = getSubprogram();
+  DILocation *L0 = DILocation::getDistinct(Context, 2, 7, N);
+  EXPECT_TRUE(L0->isDistinct());
+  DILocation *L1 = DILocation::get(Context, 2, 7, N);
+  EXPECT_FALSE(L1->isDistinct());
+  EXPECT_EQ(L1, DILocation::get(Context, 2, 7, N));
+}
+
+TEST_F(DILocationTest, getTemporary) {
+  MDNode *N = MDNode::get(Context, None);
+  auto L = DILocation::getTemporary(Context, 2, 7, N);
+  EXPECT_TRUE(L->isTemporary());
+  EXPECT_FALSE(L->isResolved());
+}
+
+TEST_F(DILocationTest, cloneTemporary) {
+  MDNode *N = MDNode::get(Context, None);
+  auto L = DILocation::getTemporary(Context, 2, 7, N);
+  EXPECT_TRUE(L->isTemporary());
+  auto L2 = L->clone();
+  EXPECT_TRUE(L2->isTemporary());
+}
+
+typedef MetadataTest GenericDINodeTest;
+
+TEST_F(GenericDINodeTest, get) {
+  StringRef Header = "header";
+  auto *Empty = MDNode::get(Context, None);
+  Metadata *Ops1[] = {Empty};
+  auto *N = GenericDINode::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, GenericDINode::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, GenericDINode::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, GenericDINode::get(Context, 15, Header, Ops1));
+
+  TempGenericDINode Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(GenericDINodeTest, getEmptyHeader) {
+  // Canonicalize !"" to null.
+  auto *N = GenericDINode::get(Context, 15, StringRef(), None);
+  EXPECT_EQ(StringRef(), N->getHeader());
+  EXPECT_EQ(nullptr, N->getOperand(0));
+}
+
+typedef MetadataTest DISubrangeTest;
+
+TEST_F(DISubrangeTest, get) {
+  auto *N = DISubrange::get(Context, 5, 7);
+  EXPECT_EQ(dwarf::DW_TAG_subrange_type, N->getTag());
+  EXPECT_EQ(5, N->getCount());
+  EXPECT_EQ(7, N->getLowerBound());
+  EXPECT_EQ(N, DISubrange::get(Context, 5, 7));
+  EXPECT_EQ(DISubrange::get(Context, 5, 0), DISubrange::get(Context, 5));
+
+  TempDISubrange Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(DISubrangeTest, getEmptyArray) {
+  auto *N = DISubrange::get(Context, -1, 0);
+  EXPECT_EQ(dwarf::DW_TAG_subrange_type, N->getTag());
+  EXPECT_EQ(-1, N->getCount());
+  EXPECT_EQ(0, N->getLowerBound());
+  EXPECT_EQ(N, DISubrange::get(Context, -1, 0));
+}
+
+typedef MetadataTest DIEnumeratorTest;
+
+TEST_F(DIEnumeratorTest, get) {
+  auto *N = DIEnumerator::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, DIEnumerator::get(Context, 7, "name"));
+
+  EXPECT_NE(N, DIEnumerator::get(Context, 8, "name"));
+  EXPECT_NE(N, DIEnumerator::get(Context, 7, "nam"));
+
+  TempDIEnumerator Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest DIBasicTypeTest;
+
+TEST_F(DIBasicTypeTest, get) {
+  auto *N =
+      DIBasicType::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, DIBasicType::get(Context, dwarf::DW_TAG_base_type, "special", 33,
+                                26, 7));
+
+  EXPECT_NE(N, DIBasicType::get(Context, dwarf::DW_TAG_unspecified_type,
+                                "special", 33, 26, 7));
+  EXPECT_NE(N,
+            DIBasicType::get(Context, dwarf::DW_TAG_base_type, "s", 33, 26, 7));
+  EXPECT_NE(N, DIBasicType::get(Context, dwarf::DW_TAG_base_type, "special", 32,
+                                26, 7));
+  EXPECT_NE(N, DIBasicType::get(Context, dwarf::DW_TAG_base_type, "special", 33,
+                                25, 7));
+  EXPECT_NE(N, DIBasicType::get(Context, dwarf::DW_TAG_base_type, "special", 33,
+                                26, 6));
+
+  TempDIBasicType Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(DIBasicTypeTest, getWithLargeValues) {
+  auto *N = DIBasicType::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());
+}
+
+TEST_F(DIBasicTypeTest, getUnspecified) {
+  auto *N =
+      DIBasicType::get(Context, dwarf::DW_TAG_unspecified_type, "unspecified");
+  EXPECT_EQ(dwarf::DW_TAG_unspecified_type, N->getTag());
+  EXPECT_EQ("unspecified", N->getName());
+  EXPECT_EQ(0u, N->getSizeInBits());
+  EXPECT_EQ(0u, N->getAlignInBits());
+  EXPECT_EQ(0u, N->getEncoding());
+  EXPECT_EQ(0u, N->getLine());
+}
+
+typedef MetadataTest DITypeTest;
+
+TEST_F(DITypeTest, clone) {
+  // Check that DIType has a specialized clone that returns TempDIType.
+  DIType *N = DIBasicType::get(Context, dwarf::DW_TAG_base_type, "int", 32, 32,
+                               dwarf::DW_ATE_signed);
+
+  TempDIType Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(DITypeTest, setFlags) {
+  // void (void)
+  Metadata *TypesOps[] = {nullptr};
+  Metadata *Types = MDTuple::get(Context, TypesOps);
+
+  DIType *D = DISubroutineType::getDistinct(Context, 0u, Types);
+  EXPECT_EQ(0u, D->getFlags());
+  D->setFlags(DINode::FlagRValueReference);
+  EXPECT_EQ(DINode::FlagRValueReference, D->getFlags());
+  D->setFlags(0u);
+  EXPECT_EQ(0u, D->getFlags());
+
+  TempDIType T = DISubroutineType::getTemporary(Context, 0u, Types);
+  EXPECT_EQ(0u, T->getFlags());
+  T->setFlags(DINode::FlagRValueReference);
+  EXPECT_EQ(DINode::FlagRValueReference, T->getFlags());
+  T->setFlags(0u);
+  EXPECT_EQ(0u, T->getFlags());
+}
+
+typedef MetadataTest DIDerivedTypeTest;
+
+TEST_F(DIDerivedTypeTest, get) {
+  DIFile *File = getFile();
+  DIScopeRef Scope = getSubprogramRef();
+  DITypeRef BaseType = getBasicType("basic");
+  MDTuple *ExtraData = getTuple();
+
+  auto *N = DIDerivedType::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, DIDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 1, Scope, BaseType, 2, 3,
+                                  4, 5, ExtraData));
+
+  EXPECT_NE(N, DIDerivedType::get(Context, dwarf::DW_TAG_reference_type,
+                                  "something", File, 1, Scope, BaseType, 2, 3,
+                                  4, 5, ExtraData));
+  EXPECT_NE(N, DIDerivedType::get(Context, dwarf::DW_TAG_pointer_type, "else",
+                                  File, 1, Scope, BaseType, 2, 3, 4, 5,
+                                  ExtraData));
+  EXPECT_NE(N, DIDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", getFile(), 1, Scope, BaseType, 2,
+                                  3, 4, 5, ExtraData));
+  EXPECT_NE(N, DIDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 2, Scope, BaseType, 2, 3,
+                                  4, 5, ExtraData));
+  EXPECT_NE(N, DIDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 1, getSubprogramRef(),
+                                  BaseType, 2, 3, 4, 5, ExtraData));
+  EXPECT_NE(N, DIDerivedType::get(
+                   Context, dwarf::DW_TAG_pointer_type, "something", File, 1,
+                   Scope, getBasicType("basic2"), 2, 3, 4, 5, ExtraData));
+  EXPECT_NE(N, DIDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 1, Scope, BaseType, 3, 3,
+                                  4, 5, ExtraData));
+  EXPECT_NE(N, DIDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 1, Scope, BaseType, 2, 2,
+                                  4, 5, ExtraData));
+  EXPECT_NE(N, DIDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 1, Scope, BaseType, 2, 3,
+                                  5, 5, ExtraData));
+  EXPECT_NE(N, DIDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 1, Scope, BaseType, 2, 3,
+                                  4, 4, ExtraData));
+  EXPECT_NE(N, DIDerivedType::get(Context, dwarf::DW_TAG_pointer_type,
+                                  "something", File, 1, Scope, BaseType, 2, 3,
+                                  4, 5, getTuple()));
+
+  TempDIDerivedType Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(DIDerivedTypeTest, getWithLargeValues) {
+  DIFile *File = getFile();
+  DIScopeRef Scope = getSubprogramRef();
+  DITypeRef BaseType = getBasicType("basic");
+  MDTuple *ExtraData = getTuple();
+
+  auto *N = DIDerivedType::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 DICompositeTypeTest;
+
+TEST_F(DICompositeTypeTest, get) {
+  unsigned Tag = dwarf::DW_TAG_structure_type;
+  StringRef Name = "some name";
+  DIFile *File = getFile();
+  unsigned Line = 1;
+  DIScopeRef Scope = getSubprogramRef();
+  DITypeRef BaseType = getCompositeType();
+  uint64_t SizeInBits = 2;
+  uint64_t AlignInBits = 3;
+  uint64_t OffsetInBits = 4;
+  unsigned Flags = 5;
+  MDTuple *Elements = getTuple();
+  unsigned RuntimeLang = 6;
+  DITypeRef VTableHolder = getCompositeType();
+  MDTuple *TemplateParams = getTuple();
+  StringRef Identifier = "some id";
+
+  auto *N = DICompositeType::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().get());
+  EXPECT_EQ(RuntimeLang, N->getRuntimeLang());
+  EXPECT_EQ(VTableHolder, N->getVTableHolder());
+  EXPECT_EQ(TemplateParams, N->getTemplateParams().get());
+  EXPECT_EQ(Identifier, N->getIdentifier());
+
+  EXPECT_EQ(N, DICompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+
+  EXPECT_NE(N, DICompositeType::get(Context, Tag + 1, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(Context, Tag, "abc", File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(Context, Tag, Name, getFile(), Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(Context, Tag, Name, File, Line + 1, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(
+                   Context, Tag, Name, File, Line, getSubprogramRef(), BaseType,
+                   SizeInBits, AlignInBits, OffsetInBits, Flags, Elements,
+                   RuntimeLang, VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(
+                   Context, Tag, Name, File, Line, Scope, getBasicType("other"),
+                   SizeInBits, AlignInBits, OffsetInBits, Flags, Elements,
+                   RuntimeLang, VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits + 1, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits + 1,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(
+                   Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
+                   AlignInBits, OffsetInBits + 1, Flags, Elements, RuntimeLang,
+                   VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(
+                   Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
+                   AlignInBits, OffsetInBits, Flags + 1, Elements, RuntimeLang,
+                   VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(
+                   Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
+                   AlignInBits, OffsetInBits, Flags, getTuple(), RuntimeLang,
+                   VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(
+                   Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
+                   AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang + 1,
+                   VTableHolder, TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(
+                   Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
+                   AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang,
+                   getCompositeType(), TemplateParams, Identifier));
+  EXPECT_NE(N, DICompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, getTuple(), Identifier));
+  EXPECT_NE(N, DICompositeType::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(DICompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams, "")
+                   ->getRawIdentifier());
+  EXPECT_FALSE(DICompositeType::get(Context, Tag, Name, File, Line, Scope,
+                                    BaseType, SizeInBits, AlignInBits,
+                                    OffsetInBits, Flags, Elements, RuntimeLang,
+                                    VTableHolder, TemplateParams)
+                   ->getRawIdentifier());
+
+  TempDICompositeType Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(DICompositeTypeTest, getWithLargeValues) {
+  unsigned Tag = dwarf::DW_TAG_structure_type;
+  StringRef Name = "some name";
+  DIFile *File = getFile();
+  unsigned Line = 1;
+  DIScopeRef Scope = getSubprogramRef();
+  DITypeRef BaseType = getCompositeType();
+  uint64_t SizeInBits = UINT64_MAX;
+  uint64_t AlignInBits = UINT64_MAX - 1;
+  uint64_t OffsetInBits = UINT64_MAX - 2;
+  unsigned Flags = 5;
+  MDTuple *Elements = getTuple();
+  unsigned RuntimeLang = 6;
+  DITypeRef VTableHolder = getCompositeType();
+  MDTuple *TemplateParams = getTuple();
+  StringRef Identifier = "some id";
+
+  auto *N = DICompositeType::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(DICompositeTypeTest, replaceOperands) {
+  unsigned Tag = dwarf::DW_TAG_structure_type;
+  StringRef Name = "some name";
+  DIFile *File = getFile();
+  unsigned Line = 1;
+  DIScopeRef Scope = getSubprogramRef();
+  DITypeRef BaseType = getCompositeType();
+  uint64_t SizeInBits = 2;
+  uint64_t AlignInBits = 3;
+  uint64_t OffsetInBits = 4;
+  unsigned Flags = 5;
+  unsigned RuntimeLang = 6;
+  StringRef Identifier = "some id";
+
+  auto *N = DICompositeType::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().get());
+  N->replaceElements(Elements);
+  EXPECT_EQ(Elements, N->getElements().get());
+  N->replaceElements(nullptr);
+  EXPECT_EQ(nullptr, N->getElements().get());
+
+  DITypeRef VTableHolder = getCompositeType();
+  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().get());
+  N->replaceTemplateParams(TemplateParams);
+  EXPECT_EQ(TemplateParams, N->getTemplateParams().get());
+  N->replaceTemplateParams(nullptr);
+  EXPECT_EQ(nullptr, N->getTemplateParams().get());
+}
+
+typedef MetadataTest DISubroutineTypeTest;
+
+TEST_F(DISubroutineTypeTest, get) {
+  unsigned Flags = 1;
+  MDTuple *TypeArray = getTuple();
+
+  auto *N = DISubroutineType::get(Context, Flags, TypeArray);
+  EXPECT_EQ(dwarf::DW_TAG_subroutine_type, N->getTag());
+  EXPECT_EQ(Flags, N->getFlags());
+  EXPECT_EQ(TypeArray, N->getTypeArray().get());
+  EXPECT_EQ(N, DISubroutineType::get(Context, Flags, TypeArray));
+
+  EXPECT_NE(N, DISubroutineType::get(Context, Flags + 1, TypeArray));
+  EXPECT_NE(N, DISubroutineType::get(Context, Flags, getTuple()));
+
+  TempDISubroutineType 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());
+}
+
+typedef MetadataTest DIFileTest;
+
+TEST_F(DIFileTest, get) {
+  StringRef Filename = "file";
+  StringRef Directory = "dir";
+  auto *N = DIFile::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, DIFile::get(Context, Filename, Directory));
+
+  EXPECT_NE(N, DIFile::get(Context, "other", Directory));
+  EXPECT_NE(N, DIFile::get(Context, Filename, "other"));
+
+  TempDIFile Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(DIFileTest, ScopeGetFile) {
+  // Ensure that DIScope::getFile() returns itself.
+  DIScope *N = DIFile::get(Context, "file", "dir");
+  EXPECT_EQ(N, N->getFile());
+}
+
+typedef MetadataTest DICompileUnitTest;
+
+TEST_F(DICompileUnitTest, get) {
+  unsigned SourceLanguage = 1;
+  DIFile *File = getFile();
+  StringRef Producer = "some producer";
+  bool IsOptimized = false;
+  StringRef Flags = "flag after flag";
+  unsigned RuntimeVersion = 2;
+  StringRef SplitDebugFilename = "another/file";
+  unsigned EmissionKind = 3;
+  MDTuple *EnumTypes = getTuple();
+  MDTuple *RetainedTypes = getTuple();
+  MDTuple *Subprograms = getTuple();
+  MDTuple *GlobalVariables = getTuple();
+  MDTuple *ImportedEntities = getTuple();
+  uint64_t DWOId = 0x10000000c0ffee;
+  auto *N = DICompileUnit::getDistinct(
+      Context, SourceLanguage, File, Producer, IsOptimized, Flags,
+      RuntimeVersion, SplitDebugFilename, EmissionKind, EnumTypes,
+      RetainedTypes, Subprograms, GlobalVariables, ImportedEntities, DWOId);
+
+  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().get());
+  EXPECT_EQ(RetainedTypes, N->getRetainedTypes().get());
+  EXPECT_EQ(Subprograms, N->getSubprograms().get());
+  EXPECT_EQ(GlobalVariables, N->getGlobalVariables().get());
+  EXPECT_EQ(ImportedEntities, N->getImportedEntities().get());
+  EXPECT_EQ(DWOId, N->getDWOId());
+
+  TempDICompileUnit Temp = N->clone();
+  EXPECT_EQ(dwarf::DW_TAG_compile_unit, Temp->getTag());
+  EXPECT_EQ(SourceLanguage, Temp->getSourceLanguage());
+  EXPECT_EQ(File, Temp->getFile());
+  EXPECT_EQ(Producer, Temp->getProducer());
+  EXPECT_EQ(IsOptimized, Temp->isOptimized());
+  EXPECT_EQ(Flags, Temp->getFlags());
+  EXPECT_EQ(RuntimeVersion, Temp->getRuntimeVersion());
+  EXPECT_EQ(SplitDebugFilename, Temp->getSplitDebugFilename());
+  EXPECT_EQ(EmissionKind, Temp->getEmissionKind());
+  EXPECT_EQ(EnumTypes, Temp->getEnumTypes().get());
+  EXPECT_EQ(RetainedTypes, Temp->getRetainedTypes().get());
+  EXPECT_EQ(Subprograms, Temp->getSubprograms().get());
+  EXPECT_EQ(GlobalVariables, Temp->getGlobalVariables().get());
+  EXPECT_EQ(ImportedEntities, Temp->getImportedEntities().get());
+  EXPECT_EQ(DWOId, Temp->getDWOId());
+
+  auto *TempAddress = Temp.get();
+  auto *Clone = MDNode::replaceWithPermanent(std::move(Temp));
+  EXPECT_TRUE(Clone->isDistinct());
+  EXPECT_EQ(TempAddress, Clone);
+}
+
+TEST_F(DICompileUnitTest, replaceArrays) {
+  unsigned SourceLanguage = 1;
+  DIFile *File = getFile();
+  StringRef Producer = "some producer";
+  bool IsOptimized = false;
+  StringRef Flags = "flag after flag";
+  unsigned RuntimeVersion = 2;
+  StringRef SplitDebugFilename = "another/file";
+  unsigned EmissionKind = 3;
+  MDTuple *EnumTypes = MDTuple::getDistinct(Context, None);
+  MDTuple *RetainedTypes = MDTuple::getDistinct(Context, None);
+  MDTuple *ImportedEntities = MDTuple::getDistinct(Context, None);
+  uint64_t DWOId = 0xc0ffee;
+  auto *N = DICompileUnit::getDistinct(
+      Context, SourceLanguage, File, Producer, IsOptimized, Flags,
+      RuntimeVersion, SplitDebugFilename, EmissionKind, EnumTypes,
+      RetainedTypes, nullptr, nullptr, ImportedEntities, DWOId);
+
+  auto *Subprograms = MDTuple::getDistinct(Context, None);
+  EXPECT_EQ(nullptr, N->getSubprograms().get());
+  N->replaceSubprograms(Subprograms);
+  EXPECT_EQ(Subprograms, N->getSubprograms().get());
+  N->replaceSubprograms(nullptr);
+  EXPECT_EQ(nullptr, N->getSubprograms().get());
+
+  auto *GlobalVariables = MDTuple::getDistinct(Context, None);
+  EXPECT_EQ(nullptr, N->getGlobalVariables().get());
+  N->replaceGlobalVariables(GlobalVariables);
+  EXPECT_EQ(GlobalVariables, N->getGlobalVariables().get());
+  N->replaceGlobalVariables(nullptr);
+  EXPECT_EQ(nullptr, N->getGlobalVariables().get());
+}
+
+typedef MetadataTest DISubprogramTest;
+
+TEST_F(DISubprogramTest, get) {
+  DIScopeRef Scope = getCompositeType();
+  StringRef Name = "name";
+  StringRef LinkageName = "linkage";
+  DIFile *File = getFile();
+  unsigned Line = 2;
+  DISubroutineType *Type = getSubroutineType();
+  bool IsLocalToUnit = false;
+  bool IsDefinition = true;
+  unsigned ScopeLine = 3;
+  DITypeRef ContainingType = getCompositeType();
+  unsigned Virtuality = 4;
+  unsigned VirtualIndex = 5;
+  unsigned Flags = 6;
+  bool IsOptimized = false;
+  MDTuple *TemplateParams = getTuple();
+  DISubprogram *Declaration = getSubprogram();
+  MDTuple *Variables = getTuple();
+
+  auto *N = DISubprogram::get(
+      Context, Scope, Name, LinkageName, File, Line, Type, IsLocalToUnit,
+      IsDefinition, ScopeLine, ContainingType, Virtuality, VirtualIndex, Flags,
+      IsOptimized, 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(TemplateParams, N->getTemplateParams().get());
+  EXPECT_EQ(Declaration, N->getDeclaration());
+  EXPECT_EQ(Variables, N->getVariables().get());
+  EXPECT_EQ(N, DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, TemplateParams,
+                                 Declaration, Variables));
+
+  EXPECT_NE(N, DISubprogram::get(Context, getCompositeType(), Name, LinkageName,
+                                 File, Line, Type, IsLocalToUnit, IsDefinition,
+                                 ScopeLine, ContainingType, Virtuality,
+                                 VirtualIndex, Flags, IsOptimized,
+                                 TemplateParams, Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, "other", LinkageName, File,
+                                 Line, Type, IsLocalToUnit, IsDefinition,
+                                 ScopeLine, ContainingType, Virtuality,
+                                 VirtualIndex, Flags, IsOptimized,
+                                 TemplateParams, Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, "other", File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, getFile(),
+                                 Line, Type, IsLocalToUnit, IsDefinition,
+                                 ScopeLine, ContainingType, Virtuality,
+                                 VirtualIndex, Flags, IsOptimized,
+                                 TemplateParams, Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, File,
+                                 Line + 1, Type, IsLocalToUnit, IsDefinition,
+                                 ScopeLine, ContainingType, Virtuality,
+                                 VirtualIndex, Flags, IsOptimized,
+                                 TemplateParams, Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 getSubroutineType(), IsLocalToUnit,
+                                 IsDefinition, ScopeLine, ContainingType,
+                                 Virtuality, VirtualIndex, Flags, IsOptimized,
+                                 TemplateParams, Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, !IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, !IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition,
+                                 ScopeLine + 1, ContainingType, Virtuality,
+                                 VirtualIndex, Flags, IsOptimized,
+                                 TemplateParams, Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 getCompositeType(), Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality + 1, VirtualIndex,
+                                 Flags, IsOptimized, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex + 1,
+                                 Flags, IsOptimized, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 ~Flags, IsOptimized, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, !IsOptimized, TemplateParams,
+                                 Declaration, Variables));
+  EXPECT_NE(N,
+            DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                              Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                              ContainingType, Virtuality, VirtualIndex, Flags,
+                              IsOptimized, getTuple(), Declaration, Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, TemplateParams,
+                                 getSubprogram(), Variables));
+  EXPECT_NE(N, DISubprogram::get(Context, Scope, Name, LinkageName, File, Line,
+                                 Type, IsLocalToUnit, IsDefinition, ScopeLine,
+                                 ContainingType, Virtuality, VirtualIndex,
+                                 Flags, IsOptimized, TemplateParams,
+                                 Declaration, getTuple()));
+
+  TempDISubprogram Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest DILexicalBlockTest;
+
+TEST_F(DILexicalBlockTest, get) {
+  DILocalScope *Scope = getSubprogram();
+  DIFile *File = getFile();
+  unsigned Line = 5;
+  unsigned Column = 8;
+
+  auto *N = DILexicalBlock::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, DILexicalBlock::get(Context, Scope, File, Line, Column));
+
+  EXPECT_NE(N,
+            DILexicalBlock::get(Context, getSubprogram(), File, Line, Column));
+  EXPECT_NE(N, DILexicalBlock::get(Context, Scope, getFile(), Line, Column));
+  EXPECT_NE(N, DILexicalBlock::get(Context, Scope, File, Line + 1, Column));
+  EXPECT_NE(N, DILexicalBlock::get(Context, Scope, File, Line, Column + 1));
+
+  TempDILexicalBlock Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(DILexicalBlockTest, Overflow) {
+  DISubprogram *SP = getSubprogram();
+  DIFile *F = getFile();
+  {
+    auto *LB = DILexicalBlock::get(Context, SP, F, 2, 7);
+    EXPECT_EQ(2u, LB->getLine());
+    EXPECT_EQ(7u, LB->getColumn());
+  }
+  unsigned U16 = 1u << 16;
+  {
+    auto *LB = DILexicalBlock::get(Context, SP, F, UINT32_MAX, U16 - 1);
+    EXPECT_EQ(UINT32_MAX, LB->getLine());
+    EXPECT_EQ(U16 - 1, LB->getColumn());
+  }
+  {
+    auto *LB = DILexicalBlock::get(Context, SP, F, UINT32_MAX, U16);
+    EXPECT_EQ(UINT32_MAX, LB->getLine());
+    EXPECT_EQ(0u, LB->getColumn());
+  }
+  {
+    auto *LB = DILexicalBlock::get(Context, SP, F, UINT32_MAX, U16 + 1);
+    EXPECT_EQ(UINT32_MAX, LB->getLine());
+    EXPECT_EQ(0u, LB->getColumn());
+  }
+}
+
+typedef MetadataTest DILexicalBlockFileTest;
+
+TEST_F(DILexicalBlockFileTest, get) {
+  DILocalScope *Scope = getSubprogram();
+  DIFile *File = getFile();
+  unsigned Discriminator = 5;
+
+  auto *N = DILexicalBlockFile::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, DILexicalBlockFile::get(Context, Scope, File, Discriminator));
+
+  EXPECT_NE(N, DILexicalBlockFile::get(Context, getSubprogram(), File,
+                                       Discriminator));
+  EXPECT_NE(N,
+            DILexicalBlockFile::get(Context, Scope, getFile(), Discriminator));
+  EXPECT_NE(N,
+            DILexicalBlockFile::get(Context, Scope, File, Discriminator + 1));
+
+  TempDILexicalBlockFile Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest DINamespaceTest;
+
+TEST_F(DINamespaceTest, get) {
+  DIScope *Scope = getFile();
+  DIFile *File = getFile();
+  StringRef Name = "namespace";
+  unsigned Line = 5;
+
+  auto *N = DINamespace::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, DINamespace::get(Context, Scope, File, Name, Line));
+
+  EXPECT_NE(N, DINamespace::get(Context, getFile(), File, Name, Line));
+  EXPECT_NE(N, DINamespace::get(Context, Scope, getFile(), Name, Line));
+  EXPECT_NE(N, DINamespace::get(Context, Scope, File, "other", Line));
+  EXPECT_NE(N, DINamespace::get(Context, Scope, File, Name, Line + 1));
+
+  TempDINamespace Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest DIModuleTest;
+
+TEST_F(DIModuleTest, get) {
+  DIScope *Scope = getFile();
+  StringRef Name = "module";
+  StringRef ConfigMacro = "-DNDEBUG";
+  StringRef Includes = "-I.";
+  StringRef Sysroot = "/";
+
+  auto *N = DIModule::get(Context, Scope, Name, ConfigMacro, Includes, Sysroot);
+
+  EXPECT_EQ(dwarf::DW_TAG_module, N->getTag());
+  EXPECT_EQ(Scope, N->getScope());
+  EXPECT_EQ(Name, N->getName());
+  EXPECT_EQ(ConfigMacro, N->getConfigurationMacros());
+  EXPECT_EQ(Includes, N->getIncludePath());
+  EXPECT_EQ(Sysroot, N->getISysRoot());
+  EXPECT_EQ(N, DIModule::get(Context, Scope, Name,
+                             ConfigMacro, Includes, Sysroot));
+  EXPECT_NE(N, DIModule::get(Context, getFile(), Name,
+                             ConfigMacro, Includes, Sysroot));
+  EXPECT_NE(N, DIModule::get(Context, Scope, "other",
+                             ConfigMacro, Includes, Sysroot));
+  EXPECT_NE(N, DIModule::get(Context, Scope, Name,
+                             "other", Includes, Sysroot));
+  EXPECT_NE(N, DIModule::get(Context, Scope, Name,
+                             ConfigMacro, "other", Sysroot));
+  EXPECT_NE(N, DIModule::get(Context, Scope, Name,
+                             ConfigMacro, Includes, "other"));
+
+  TempDIModule Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest DITemplateTypeParameterTest;
+
+TEST_F(DITemplateTypeParameterTest, get) {
+  StringRef Name = "template";
+  DITypeRef Type = getBasicType("basic");
+
+  auto *N = DITemplateTypeParameter::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, DITemplateTypeParameter::get(Context, Name, Type));
+
+  EXPECT_NE(N, DITemplateTypeParameter::get(Context, "other", Type));
+  EXPECT_NE(N,
+            DITemplateTypeParameter::get(Context, Name, getBasicType("other")));
+
+  TempDITemplateTypeParameter Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest DITemplateValueParameterTest;
+
+TEST_F(DITemplateValueParameterTest, get) {
+  unsigned Tag = dwarf::DW_TAG_template_value_parameter;
+  StringRef Name = "template";
+  DITypeRef Type = getBasicType("basic");
+  Metadata *Value = getConstantAsMetadata();
+
+  auto *N = DITemplateValueParameter::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, DITemplateValueParameter::get(Context, Tag, Name, Type, Value));
+
+  EXPECT_NE(N, DITemplateValueParameter::get(
+                   Context, dwarf::DW_TAG_GNU_template_template_param, Name,
+                   Type, Value));
+  EXPECT_NE(N,
+            DITemplateValueParameter::get(Context, Tag, "other", Type, Value));
+  EXPECT_NE(N, DITemplateValueParameter::get(Context, Tag, Name,
+                                             getBasicType("other"), Value));
+  EXPECT_NE(N, DITemplateValueParameter::get(Context, Tag, Name, Type,
+                                             getConstantAsMetadata()));
+
+  TempDITemplateValueParameter Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest DIGlobalVariableTest;
+
+TEST_F(DIGlobalVariableTest, get) {
+  DIScope *Scope = getSubprogram();
+  StringRef Name = "name";
+  StringRef LinkageName = "linkage";
+  DIFile *File = getFile();
+  unsigned Line = 5;
+  DITypeRef Type = getDerivedType();
+  bool IsLocalToUnit = false;
+  bool IsDefinition = true;
+  Constant *Variable = getConstant();
+  DIDerivedType *StaticDataMemberDeclaration =
+      cast<DIDerivedType>(getDerivedType());
+
+  auto *N = DIGlobalVariable::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, DIGlobalVariable::get(Context, Scope, Name, LinkageName, File,
+                                     Line, Type, IsLocalToUnit, IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+
+  EXPECT_NE(N,
+            DIGlobalVariable::get(Context, getSubprogram(), Name, LinkageName,
+                                  File, Line, Type, IsLocalToUnit, IsDefinition,
+                                  Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N, DIGlobalVariable::get(Context, Scope, "other", LinkageName, File,
+                                     Line, Type, IsLocalToUnit, IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N, DIGlobalVariable::get(Context, Scope, Name, "other", File, Line,
+                                     Type, IsLocalToUnit, IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N,
+            DIGlobalVariable::get(Context, Scope, Name, LinkageName, getFile(),
+                                  Line, Type, IsLocalToUnit, IsDefinition,
+                                  Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N,
+            DIGlobalVariable::get(Context, Scope, Name, LinkageName, File,
+                                  Line + 1, Type, IsLocalToUnit, IsDefinition,
+                                  Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N,
+            DIGlobalVariable::get(Context, Scope, Name, LinkageName, File, Line,
+                                  getDerivedType(), IsLocalToUnit, IsDefinition,
+                                  Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N, DIGlobalVariable::get(Context, Scope, Name, LinkageName, File,
+                                     Line, Type, !IsLocalToUnit, IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N, DIGlobalVariable::get(Context, Scope, Name, LinkageName, File,
+                                     Line, Type, IsLocalToUnit, !IsDefinition,
+                                     Variable, StaticDataMemberDeclaration));
+  EXPECT_NE(N,
+            DIGlobalVariable::get(Context, Scope, Name, LinkageName, File, Line,
+                                  Type, IsLocalToUnit, IsDefinition,
+                                  getConstant(), StaticDataMemberDeclaration));
+  EXPECT_NE(N,
+            DIGlobalVariable::get(Context, Scope, Name, LinkageName, File, Line,
+                                  Type, IsLocalToUnit, IsDefinition, Variable,
+                                  cast<DIDerivedType>(getDerivedType())));
+
+  TempDIGlobalVariable Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest DILocalVariableTest;
+
+TEST_F(DILocalVariableTest, get) {
+  DILocalScope *Scope = getSubprogram();
+  StringRef Name = "name";
+  DIFile *File = getFile();
+  unsigned Line = 5;
+  DITypeRef Type = getDerivedType();
+  unsigned Arg = 6;
+  unsigned Flags = 7;
+
+  auto *N =
+      DILocalVariable::get(Context, Scope, Name, File, Line, Type, Arg, Flags);
+  EXPECT_TRUE(N->isParameter());
+  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(N, DILocalVariable::get(Context, Scope, Name, File, Line, Type, Arg,
+                                    Flags));
+
+  EXPECT_FALSE(
+      DILocalVariable::get(Context, Scope, Name, File, Line, Type, 0, Flags)
+          ->isParameter());
+  EXPECT_NE(N, DILocalVariable::get(Context, getSubprogram(), Name, File, Line,
+                                    Type, Arg, Flags));
+  EXPECT_NE(N, DILocalVariable::get(Context, Scope, "other", File, Line, Type,
+                                    Arg, Flags));
+  EXPECT_NE(N, DILocalVariable::get(Context, Scope, Name, getFile(), Line, Type,
+                                    Arg, Flags));
+  EXPECT_NE(N, DILocalVariable::get(Context, Scope, Name, File, Line + 1, Type,
+                                    Arg, Flags));
+  EXPECT_NE(N, DILocalVariable::get(Context, Scope, Name, File, Line,
+                                    getDerivedType(), Arg, Flags));
+  EXPECT_NE(N, DILocalVariable::get(Context, Scope, Name, File, Line, Type,
+                                    Arg + 1, Flags));
+  EXPECT_NE(N, DILocalVariable::get(Context, Scope, Name, File, Line, Type, Arg,
+                                    ~Flags));
+
+  TempDILocalVariable Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(DILocalVariableTest, getArg256) {
+  EXPECT_EQ(255u, DILocalVariable::get(Context, getSubprogram(), "", getFile(),
+                                       0, nullptr, 255, 0)
+                      ->getArg());
+  EXPECT_EQ(256u, DILocalVariable::get(Context, getSubprogram(), "", getFile(),
+                                       0, nullptr, 256, 0)
+                      ->getArg());
+  EXPECT_EQ(257u, DILocalVariable::get(Context, getSubprogram(), "", getFile(),
+                                       0, nullptr, 257, 0)
+                      ->getArg());
+  unsigned Max = UINT16_MAX;
+  EXPECT_EQ(Max, DILocalVariable::get(Context, getSubprogram(), "", getFile(),
+                                      0, nullptr, Max, 0)
+                     ->getArg());
+}
+
+typedef MetadataTest DIExpressionTest;
+
+TEST_F(DIExpressionTest, get) {
+  uint64_t Elements[] = {2, 6, 9, 78, 0};
+  auto *N = DIExpression::get(Context, Elements);
+  EXPECT_EQ(makeArrayRef(Elements), N->getElements());
+  EXPECT_EQ(N, DIExpression::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));
+
+  TempDIExpression Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+TEST_F(DIExpressionTest, isValid) {
+#define EXPECT_VALID(...)                                                      \
+  do {                                                                         \
+    uint64_t Elements[] = {__VA_ARGS__};                                       \
+    EXPECT_TRUE(DIExpression::get(Context, Elements)->isValid());              \
+  } while (false)
+#define EXPECT_INVALID(...)                                                    \
+  do {                                                                         \
+    uint64_t Elements[] = {__VA_ARGS__};                                       \
+    EXPECT_FALSE(DIExpression::get(Context, Elements)->isValid());             \
+  } while (false)
+
+  // Empty expression should be valid.
+  EXPECT_TRUE(DIExpression::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 DIObjCPropertyTest;
+
+TEST_F(DIObjCPropertyTest, get) {
+  StringRef Name = "name";
+  DIFile *File = getFile();
+  unsigned Line = 5;
+  StringRef GetterName = "getter";
+  StringRef SetterName = "setter";
+  unsigned Attributes = 7;
+  DITypeRef Type = getBasicType("basic");
+
+  auto *N = DIObjCProperty::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, DIObjCProperty::get(Context, Name, File, Line, GetterName,
+                                   SetterName, Attributes, Type));
+
+  EXPECT_NE(N, DIObjCProperty::get(Context, "other", File, Line, GetterName,
+                                   SetterName, Attributes, Type));
+  EXPECT_NE(N, DIObjCProperty::get(Context, Name, getFile(), Line, GetterName,
+                                   SetterName, Attributes, Type));
+  EXPECT_NE(N, DIObjCProperty::get(Context, Name, File, Line + 1, GetterName,
+                                   SetterName, Attributes, Type));
+  EXPECT_NE(N, DIObjCProperty::get(Context, Name, File, Line, "other",
+                                   SetterName, Attributes, Type));
+  EXPECT_NE(N, DIObjCProperty::get(Context, Name, File, Line, GetterName,
+                                   "other", Attributes, Type));
+  EXPECT_NE(N, DIObjCProperty::get(Context, Name, File, Line, GetterName,
+                                   SetterName, Attributes + 1, Type));
+  EXPECT_NE(N, DIObjCProperty::get(Context, Name, File, Line, GetterName,
+                                   SetterName, Attributes,
+                                   getBasicType("other")));
+
+  TempDIObjCProperty Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
+typedef MetadataTest DIImportedEntityTest;
+
+TEST_F(DIImportedEntityTest, get) {
+  unsigned Tag = dwarf::DW_TAG_imported_module;
+  DIScope *Scope = getSubprogram();
+  DINodeRef Entity = getCompositeType();
+  unsigned Line = 5;
+  StringRef Name = "name";
+
+  auto *N = DIImportedEntity::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, DIImportedEntity::get(Context, Tag, Scope, Entity, Line, Name));
+
+  EXPECT_NE(N,
+            DIImportedEntity::get(Context, dwarf::DW_TAG_imported_declaration,
+                                  Scope, Entity, Line, Name));
+  EXPECT_NE(N, DIImportedEntity::get(Context, Tag, getSubprogram(), Entity,
+                                     Line, Name));
+  EXPECT_NE(N, DIImportedEntity::get(Context, Tag, Scope, getCompositeType(),
+                                     Line, Name));
+  EXPECT_NE(N,
+            DIImportedEntity::get(Context, Tag, Scope, Entity, Line + 1, Name));
+  EXPECT_NE(N,
+            DIImportedEntity::get(Context, Tag, Scope, Entity, Line, "other"));
+
+  TempDIImportedEntity Temp = N->clone();
+  EXPECT_EQ(N, MDNode::replaceWithUniqued(std::move(Temp)));
+}
+
 typedef MetadataTest MetadataAsValueTest;
 
 TEST_F(MetadataAsValueTest, MDNode) {
@@ -282,6 +2048,34 @@ TEST_F(ValueAsMetadataTest, UpdatesOnRAUW) {
   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) {
@@ -337,4 +2131,149 @@ TEST(NamedMDNodeTest, Search) {
   EXPECT_STREQ("!llvm.NMD1 = !{!0, !1}\n",
                oss.str().c_str());
 }
+
+typedef MetadataTest FunctionAttachmentTest;
+TEST_F(FunctionAttachmentTest, setMetadata) {
+  Function *F = getFunction("foo");
+  ASSERT_FALSE(F->hasMetadata());
+  EXPECT_EQ(nullptr, F->getMetadata(LLVMContext::MD_dbg));
+  EXPECT_EQ(nullptr, F->getMetadata("dbg"));
+  EXPECT_EQ(nullptr, F->getMetadata("other"));
+
+  DISubprogram *SP1 = getSubprogram();
+  DISubprogram *SP2 = getSubprogram();
+  ASSERT_NE(SP1, SP2);
+
+  F->setMetadata("dbg", SP1);
+  EXPECT_TRUE(F->hasMetadata());
+  EXPECT_EQ(SP1, F->getMetadata(LLVMContext::MD_dbg));
+  EXPECT_EQ(SP1, F->getMetadata("dbg"));
+  EXPECT_EQ(nullptr, F->getMetadata("other"));
+
+  F->setMetadata(LLVMContext::MD_dbg, SP2);
+  EXPECT_TRUE(F->hasMetadata());
+  EXPECT_EQ(SP2, F->getMetadata(LLVMContext::MD_dbg));
+  EXPECT_EQ(SP2, F->getMetadata("dbg"));
+  EXPECT_EQ(nullptr, F->getMetadata("other"));
+
+  F->setMetadata("dbg", nullptr);
+  EXPECT_FALSE(F->hasMetadata());
+  EXPECT_EQ(nullptr, F->getMetadata(LLVMContext::MD_dbg));
+  EXPECT_EQ(nullptr, F->getMetadata("dbg"));
+  EXPECT_EQ(nullptr, F->getMetadata("other"));
+
+  MDTuple *T1 = getTuple();
+  MDTuple *T2 = getTuple();
+  ASSERT_NE(T1, T2);
+
+  F->setMetadata("other1", T1);
+  F->setMetadata("other2", T2);
+  EXPECT_TRUE(F->hasMetadata());
+  EXPECT_EQ(T1, F->getMetadata("other1"));
+  EXPECT_EQ(T2, F->getMetadata("other2"));
+  EXPECT_EQ(nullptr, F->getMetadata("dbg"));
+
+  F->setMetadata("other1", T2);
+  F->setMetadata("other2", T1);
+  EXPECT_EQ(T2, F->getMetadata("other1"));
+  EXPECT_EQ(T1, F->getMetadata("other2"));
+
+  F->setMetadata("other1", nullptr);
+  F->setMetadata("other2", nullptr);
+  EXPECT_FALSE(F->hasMetadata());
+  EXPECT_EQ(nullptr, F->getMetadata("other1"));
+  EXPECT_EQ(nullptr, F->getMetadata("other2"));
+}
+
+TEST_F(FunctionAttachmentTest, getAll) {
+  Function *F = getFunction("foo");
+
+  MDTuple *T1 = getTuple();
+  MDTuple *T2 = getTuple();
+  MDTuple *P = getTuple();
+  DISubprogram *SP = getSubprogram();
+
+  F->setMetadata("other1", T2);
+  F->setMetadata(LLVMContext::MD_dbg, SP);
+  F->setMetadata("other2", T1);
+  F->setMetadata(LLVMContext::MD_prof, P);
+  F->setMetadata("other2", T2);
+  F->setMetadata("other1", T1);
+
+  SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
+  F->getAllMetadata(MDs);
+  ASSERT_EQ(4u, MDs.size());
+  EXPECT_EQ(LLVMContext::MD_dbg, MDs[0].first);
+  EXPECT_EQ(LLVMContext::MD_prof, MDs[1].first);
+  EXPECT_EQ(Context.getMDKindID("other1"), MDs[2].first);
+  EXPECT_EQ(Context.getMDKindID("other2"), MDs[3].first);
+  EXPECT_EQ(SP, MDs[0].second);
+  EXPECT_EQ(P, MDs[1].second);
+  EXPECT_EQ(T1, MDs[2].second);
+  EXPECT_EQ(T2, MDs[3].second);
+}
+
+TEST_F(FunctionAttachmentTest, dropUnknownMetadata) {
+  Function *F = getFunction("foo");
+
+  MDTuple *T1 = getTuple();
+  MDTuple *T2 = getTuple();
+  MDTuple *P = getTuple();
+  DISubprogram *SP = getSubprogram();
+
+  F->setMetadata("other1", T1);
+  F->setMetadata(LLVMContext::MD_dbg, SP);
+  F->setMetadata("other2", T2);
+  F->setMetadata(LLVMContext::MD_prof, P);
+
+  unsigned Known[] = {Context.getMDKindID("other2"), LLVMContext::MD_prof};
+  F->dropUnknownMetadata(Known);
+
+  EXPECT_EQ(T2, F->getMetadata("other2"));
+  EXPECT_EQ(P, F->getMetadata(LLVMContext::MD_prof));
+  EXPECT_EQ(nullptr, F->getMetadata("other1"));
+  EXPECT_EQ(nullptr, F->getMetadata(LLVMContext::MD_dbg));
+
+  F->setMetadata("other2", nullptr);
+  F->setMetadata(LLVMContext::MD_prof, nullptr);
+  EXPECT_FALSE(F->hasMetadata());
+}
+
+TEST_F(FunctionAttachmentTest, Verifier) {
+  Function *F = getFunction("foo");
+  F->setMetadata("attach", getTuple());
+
+  // Confirm this has no body.
+  ASSERT_TRUE(F->empty());
+
+  // Functions without a body cannot have metadata attachments (they also can't
+  // be verified directly, so check that the module fails to verify).
+  EXPECT_TRUE(verifyModule(*F->getParent()));
+
+  // Functions with a body can.
+  (void)new UnreachableInst(Context, BasicBlock::Create(Context, "bb", F));
+  EXPECT_FALSE(verifyModule(*F->getParent()));
+  EXPECT_FALSE(verifyFunction(*F));
+}
+
+TEST_F(FunctionAttachmentTest, EntryCount) {
+  Function *F = getFunction("foo");
+  EXPECT_FALSE(F->getEntryCount().hasValue());
+  F->setEntryCount(12304);
+  EXPECT_TRUE(F->getEntryCount().hasValue());
+  EXPECT_EQ(12304u, *F->getEntryCount());
+}
+
+TEST_F(FunctionAttachmentTest, SubprogramAttachment) {
+  Function *F = getFunction("foo");
+  DISubprogram *SP = getSubprogram();
+  F->setSubprogram(SP);
+
+  // Note that the static_cast confirms that F->getSubprogram() actually
+  // returns an DISubprogram.
+  EXPECT_EQ(SP, static_cast<DISubprogram *>(F->getSubprogram()));
+  EXPECT_EQ(SP, F->getMetadata("dbg"));
+  EXPECT_EQ(SP, F->getMetadata(LLVMContext::MD_dbg));
+}
+
 }