X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FIR%2FVerifier.cpp;h=6545361793e61a0c28b688aa02e331f1d04f0a99;hb=dad20b2ae2544708d6a33abdb9bddd0a329f50e0;hp=deb708da17e30600b00ed227aa8f0cbdc1d6b104;hpb=67f6bf70d2cdb8fe74fe6872d90b7d09afe5dd69;p=oota-llvm.git

diff --git a/lib/IR/Verifier.cpp b/lib/IR/Verifier.cpp
index deb708da17e..6545361793e 100644
--- a/lib/IR/Verifier.cpp
+++ b/lib/IR/Verifier.cpp
@@ -61,12 +61,14 @@
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/IR/InlineAsm.h"
+#include "llvm/IR/InstIterator.h"
 #include "llvm/IR/InstVisitor.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Metadata.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/PassManager.h"
+#include "llvm/IR/Statepoint.h"
 #include "llvm/Pass.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
@@ -76,15 +78,108 @@
 #include <cstdarg>
 using namespace llvm;
 
-static cl::opt<bool> DisableDebugInfoVerifier("disable-debug-info-verifier",
-                                              cl::init(true));
+static cl::opt<bool> VerifyDebugInfo("verify-debug-info", cl::init(false));
 
 namespace {
-class Verifier : public InstVisitor<Verifier> {
-  friend class InstVisitor<Verifier>;
-
+struct VerifierSupport {
   raw_ostream &OS;
   const Module *M;
+
+  /// \brief Track the brokenness of the module while recursively visiting.
+  bool Broken;
+
+  explicit VerifierSupport(raw_ostream &OS)
+      : OS(OS), M(nullptr), Broken(false) {}
+
+  void WriteValue(const Value *V) {
+    if (!V)
+      return;
+    if (isa<Instruction>(V)) {
+      OS << *V << '\n';
+    } else {
+      V->printAsOperand(OS, true, M);
+      OS << '\n';
+    }
+  }
+
+  void WriteMetadata(const Metadata *MD) {
+    if (!MD)
+      return;
+    MD->printAsOperand(OS, true, M);
+    OS << '\n';
+  }
+
+  void WriteType(Type *T) {
+    if (!T)
+      return;
+    OS << ' ' << *T;
+  }
+
+  void WriteComdat(const Comdat *C) {
+    if (!C)
+      return;
+    OS << *C;
+  }
+
+  // CheckFailed - A check failed, so print out the condition and the message
+  // that failed.  This provides a nice place to put a breakpoint if you want
+  // to see why something is not correct.
+  void CheckFailed(const Twine &Message, const Value *V1 = nullptr,
+                   const Value *V2 = nullptr, const Value *V3 = nullptr,
+                   const Value *V4 = nullptr) {
+    OS << Message.str() << "\n";
+    WriteValue(V1);
+    WriteValue(V2);
+    WriteValue(V3);
+    WriteValue(V4);
+    Broken = true;
+  }
+
+  void CheckFailed(const Twine &Message, const Metadata *V1, const Metadata *V2,
+                   const Metadata *V3 = nullptr, const Metadata *V4 = nullptr) {
+    OS << Message.str() << "\n";
+    WriteMetadata(V1);
+    WriteMetadata(V2);
+    WriteMetadata(V3);
+    WriteMetadata(V4);
+    Broken = true;
+  }
+
+  void CheckFailed(const Twine &Message, const Metadata *V1,
+                   const Value *V2 = nullptr) {
+    OS << Message.str() << "\n";
+    WriteMetadata(V1);
+    WriteValue(V2);
+    Broken = true;
+  }
+
+  void CheckFailed(const Twine &Message, const Value *V1, Type *T2,
+                   const Value *V3 = nullptr) {
+    OS << Message.str() << "\n";
+    WriteValue(V1);
+    WriteType(T2);
+    WriteValue(V3);
+    Broken = true;
+  }
+
+  void CheckFailed(const Twine &Message, Type *T1, Type *T2 = nullptr,
+                   Type *T3 = nullptr) {
+    OS << Message.str() << "\n";
+    WriteType(T1);
+    WriteType(T2);
+    WriteType(T3);
+    Broken = true;
+  }
+
+  void CheckFailed(const Twine &Message, const Comdat *C) {
+    OS << Message.str() << "\n";
+    WriteComdat(C);
+    Broken = true;
+  }
+};
+class Verifier : public InstVisitor<Verifier>, VerifierSupport {
+  friend class InstVisitor<Verifier>;
+
   LLVMContext *Context;
   const DataLayout *DL;
   DominatorTree DT;
@@ -97,22 +192,17 @@ class Verifier : public InstVisitor<Verifier> {
   SmallPtrSet<Instruction *, 16> InstsInThisBlock;
 
   /// \brief Keep track of the metadata nodes that have been checked already.
-  SmallPtrSet<MDNode *, 32> MDNodes;
+  SmallPtrSet<Metadata *, 32> MDNodes;
 
   /// \brief The personality function referenced by the LandingPadInsts.
   /// All LandingPadInsts within the same function must use the same
   /// personality function.
   const Value *PersonalityFn;
 
-  /// \brief Finder keeps track of all debug info MDNodes in a Module.
-  DebugInfoFinder Finder;
-
-  /// \brief Track the brokenness of the module while recursively visiting.
-  bool Broken;
-
 public:
   explicit Verifier(raw_ostream &OS = dbgs())
-      : OS(OS), M(0), Context(0), DL(0), PersonalityFn(0), Broken(false) {}
+      : VerifierSupport(OS), Context(nullptr), DL(nullptr),
+        PersonalityFn(nullptr) {}
 
   bool verify(const Function &F) {
     M = F.getParent();
@@ -142,16 +232,11 @@ public:
     // FIXME: It's really gross that we have to cast away constness here.
     DT.recalculate(const_cast<Function &>(F));
 
-    Finder.reset();
     Broken = false;
     // FIXME: We strip const here because the inst visitor strips const.
     visit(const_cast<Function &>(F));
     InstsInThisBlock.clear();
-    PersonalityFn = 0;
-
-    if (!DisableDebugInfoVerifier)
-      // Verify Debug Info.
-      verifyDebugInfo();
+    PersonalityFn = nullptr;
 
     return !Broken;
   }
@@ -159,7 +244,6 @@ public:
   bool verify(const Module &M) {
     this->M = &M;
     Context = &M.getContext();
-    Finder.reset();
     Broken = false;
 
     // Scan through, checking all of the external function's linkage now...
@@ -184,16 +268,12 @@ public:
          I != E; ++I)
       visitNamedMDNode(*I);
 
+    for (const StringMapEntry<Comdat> &SMEC : M.getComdatSymbolTable())
+      visitComdat(SMEC.getValue());
+
     visitModuleFlags(M);
     visitModuleIdents(M);
 
-    if (!DisableDebugInfoVerifier) {
-      Finder.reset();
-      Finder.processModule(M);
-      // Verify Debug Info.
-      verifyDebugInfo();
-    }
-
     return !Broken;
   }
 
@@ -202,8 +282,14 @@ private:
   void visitGlobalValue(const GlobalValue &GV);
   void visitGlobalVariable(const GlobalVariable &GV);
   void visitGlobalAlias(const GlobalAlias &GA);
+  void visitAliaseeSubExpr(const GlobalAlias &A, const Constant &C);
+  void visitAliaseeSubExpr(SmallPtrSetImpl<const GlobalAlias *> &Visited,
+                           const GlobalAlias &A, const Constant &C);
   void visitNamedMDNode(const NamedMDNode &NMD);
-  void visitMDNode(MDNode &MD, Function *F);
+  void visitMDNode(MDNode &MD);
+  void visitMetadataAsValue(MetadataAsValue &MD, Function *F);
+  void visitValueAsMetadata(ValueAsMetadata &MD, Function *F);
+  void visitComdat(const Comdat &C);
   void visitModuleIdents(const Module &M);
   void visitModuleFlags(const Module &M);
   void visitModuleFlag(const MDNode *Op,
@@ -211,6 +297,8 @@ private:
                        SmallVectorImpl<const MDNode *> &Requirements);
   void visitFunction(const Function &F);
   void visitBasicBlock(BasicBlock &BB);
+  void visitRangeMetadata(Instruction& I, MDNode* Range, Type* Ty);
+
 
   // InstVisitor overrides...
   using InstVisitor<Verifier>::visit;
@@ -262,6 +350,7 @@ private:
   void visitLandingPadInst(LandingPadInst &LPI);
 
   void VerifyCallSite(CallSite CS);
+  void verifyMustTailCall(CallInst &CI);
   bool PerformTypeCheck(Intrinsic::ID ID, Function *F, Type *Ty, int VT,
                         unsigned ArgNo, std::string &Suffix);
   bool VerifyIntrinsicType(Type *Ty, ArrayRef<Intrinsic::IITDescriptor> &Infos,
@@ -278,56 +367,21 @@ private:
 
   void VerifyBitcastType(const Value *V, Type *DestTy, Type *SrcTy);
   void VerifyConstantExprBitcastType(const ConstantExpr *CE);
+};
+class DebugInfoVerifier : public VerifierSupport {
+public:
+  explicit DebugInfoVerifier(raw_ostream &OS = dbgs()) : VerifierSupport(OS) {}
 
-  void verifyDebugInfo();
-
-  void WriteValue(const Value *V) {
-    if (!V)
-      return;
-    if (isa<Instruction>(V)) {
-      OS << *V << '\n';
-    } else {
-      V->printAsOperand(OS, true, M);
-      OS << '\n';
-    }
-  }
-
-  void WriteType(Type *T) {
-    if (!T)
-      return;
-    OS << ' ' << *T;
-  }
-
-  // CheckFailed - A check failed, so print out the condition and the message
-  // that failed.  This provides a nice place to put a breakpoint if you want
-  // to see why something is not correct.
-  void CheckFailed(const Twine &Message, const Value *V1 = 0,
-                   const Value *V2 = 0, const Value *V3 = 0,
-                   const Value *V4 = 0) {
-    OS << Message.str() << "\n";
-    WriteValue(V1);
-    WriteValue(V2);
-    WriteValue(V3);
-    WriteValue(V4);
-    Broken = true;
-  }
-
-  void CheckFailed(const Twine &Message, const Value *V1, Type *T2,
-                   const Value *V3 = 0) {
-    OS << Message.str() << "\n";
-    WriteValue(V1);
-    WriteType(T2);
-    WriteValue(V3);
-    Broken = true;
+  bool verify(const Module &M) {
+    this->M = &M;
+    verifyDebugInfo();
+    return !Broken;
   }
 
-  void CheckFailed(const Twine &Message, Type *T1, Type *T2 = 0, Type *T3 = 0) {
-    OS << Message.str() << "\n";
-    WriteType(T1);
-    WriteType(T2);
-    WriteType(T3);
-    Broken = true;
-  }
+private:
+  void verifyDebugInfo();
+  void processInstructions(DebugInfoFinder &Finder);
+  void processCallInst(DebugInfoFinder &Finder, const CallInst &CI);
 };
 } // End anonymous namespace
 
@@ -345,21 +399,19 @@ private:
 
 void Verifier::visit(Instruction &I) {
   for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
-    Assert1(I.getOperand(i) != 0, "Operand is null", &I);
+    Assert1(I.getOperand(i) != nullptr, "Operand is null", &I);
   InstVisitor<Verifier>::visit(I);
 }
 
 
 void Verifier::visitGlobalValue(const GlobalValue &GV) {
-  Assert1(!GV.isDeclaration() ||
-          GV.isMaterializable() ||
-          GV.hasExternalLinkage() ||
-          GV.hasExternalWeakLinkage() ||
-          (isa<GlobalAlias>(GV) &&
-           (GV.hasLocalLinkage() || GV.hasWeakLinkage())),
+  Assert1(!GV.isDeclaration() || GV.hasExternalLinkage() ||
+              GV.hasExternalWeakLinkage(),
           "Global is external, but doesn't have external or weak linkage!",
           &GV);
 
+  Assert1(GV.getAlignment() <= Value::MaximumAlignment,
+          "huge alignment values are unsupported", &GV);
   Assert1(!GV.hasAppendingLinkage() || isa<GlobalVariable>(GV),
           "Only global variables can have appending linkage!", &GV);
 
@@ -383,6 +435,7 @@ void Verifier::visitGlobalVariable(const GlobalVariable &GV) {
               "'common' global must have a zero initializer!", &GV);
       Assert1(!GV.isConstant(), "'common' global may not be marked constant!",
               &GV);
+      Assert1(!GV.hasComdat(), "'common' global may not be in a Comdat!", &GV);
     }
   } else {
     Assert1(GV.hasExternalLinkage() || GV.hasExternalWeakLinkage(),
@@ -395,14 +448,22 @@ void Verifier::visitGlobalVariable(const GlobalVariable &GV) {
             "invalid linkage for intrinsic global variable", &GV);
     // Don't worry about emitting an error for it not being an array,
     // visitGlobalValue will complain on appending non-array.
-    if (ArrayType *ATy = dyn_cast<ArrayType>(GV.getType())) {
+    if (ArrayType *ATy = dyn_cast<ArrayType>(GV.getType()->getElementType())) {
       StructType *STy = dyn_cast<StructType>(ATy->getElementType());
       PointerType *FuncPtrTy =
           FunctionType::get(Type::getVoidTy(*Context), false)->getPointerTo();
-      Assert1(STy && STy->getNumElements() == 2 &&
+      // FIXME: Reject the 2-field form in LLVM 4.0.
+      Assert1(STy && (STy->getNumElements() == 2 ||
+                      STy->getNumElements() == 3) &&
               STy->getTypeAtIndex(0u)->isIntegerTy(32) &&
               STy->getTypeAtIndex(1) == FuncPtrTy,
               "wrong type for intrinsic global variable", &GV);
+      if (STy->getNumElements() == 3) {
+        Type *ETy = STy->getTypeAtIndex(2);
+        Assert1(ETy->isPointerTy() &&
+                    cast<PointerType>(ETy)->getElementType()->isIntegerTy(8),
+                "wrong type for intrinsic global variable", &GV);
+      }
     }
   }
 
@@ -447,7 +508,7 @@ void Verifier::visitGlobalVariable(const GlobalVariable &GV) {
 
   while (!WorkStack.empty()) {
     const Value *V = WorkStack.pop_back_val();
-    if (!Visited.insert(V))
+    if (!Visited.insert(V).second)
       continue;
 
     if (const User *U = dyn_cast<User>(V)) {
@@ -465,45 +526,57 @@ void Verifier::visitGlobalVariable(const GlobalVariable &GV) {
   visitGlobalValue(GV);
 }
 
+void Verifier::visitAliaseeSubExpr(const GlobalAlias &GA, const Constant &C) {
+  SmallPtrSet<const GlobalAlias*, 4> Visited;
+  Visited.insert(&GA);
+  visitAliaseeSubExpr(Visited, GA, C);
+}
+
+void Verifier::visitAliaseeSubExpr(SmallPtrSetImpl<const GlobalAlias*> &Visited,
+                                   const GlobalAlias &GA, const Constant &C) {
+  if (const auto *GV = dyn_cast<GlobalValue>(&C)) {
+    Assert1(!GV->isDeclaration(), "Alias must point to a definition", &GA);
+
+    if (const auto *GA2 = dyn_cast<GlobalAlias>(GV)) {
+      Assert1(Visited.insert(GA2).second, "Aliases cannot form a cycle", &GA);
+
+      Assert1(!GA2->mayBeOverridden(), "Alias cannot point to a weak alias",
+              &GA);
+    } else {
+      // Only continue verifying subexpressions of GlobalAliases.
+      // Do not recurse into global initializers.
+      return;
+    }
+  }
+
+  if (const auto *CE = dyn_cast<ConstantExpr>(&C))
+    VerifyConstantExprBitcastType(CE);
+
+  for (const Use &U : C.operands()) {
+    Value *V = &*U;
+    if (const auto *GA2 = dyn_cast<GlobalAlias>(V))
+      visitAliaseeSubExpr(Visited, GA, *GA2->getAliasee());
+    else if (const auto *C2 = dyn_cast<Constant>(V))
+      visitAliaseeSubExpr(Visited, GA, *C2);
+  }
+}
+
 void Verifier::visitGlobalAlias(const GlobalAlias &GA) {
   Assert1(!GA.getName().empty(),
           "Alias name cannot be empty!", &GA);
   Assert1(GlobalAlias::isValidLinkage(GA.getLinkage()),
-          "Alias should have external or external weak linkage!", &GA);
-  Assert1(GA.getAliasee(),
-          "Aliasee cannot be NULL!", &GA);
-  Assert1(GA.getType() == GA.getAliasee()->getType(),
-          "Alias and aliasee types should match!", &GA);
-  Assert1(!GA.hasUnnamedAddr(), "Alias cannot have unnamed_addr!", &GA);
-  Assert1(!GA.hasSection(), "Alias cannot have a section!", &GA);
-  Assert1(!GA.getAlignment(), "Alias connot have an alignment", &GA);
-
+          "Alias should have private, internal, linkonce, weak, linkonce_odr, "
+          "weak_odr, or external linkage!",
+          &GA);
   const Constant *Aliasee = GA.getAliasee();
+  Assert1(Aliasee, "Aliasee cannot be NULL!", &GA);
+  Assert1(GA.getType() == Aliasee->getType(),
+          "Alias and aliasee types should match!", &GA);
 
-  if (!isa<GlobalValue>(Aliasee)) {
-    const ConstantExpr *CE = dyn_cast<ConstantExpr>(Aliasee);
-    Assert1(CE &&
-            (CE->getOpcode() == Instruction::BitCast ||
-             CE->getOpcode() == Instruction::AddrSpaceCast ||
-             CE->getOpcode() == Instruction::GetElementPtr) &&
-            isa<GlobalValue>(CE->getOperand(0)),
-            "Aliasee should be either GlobalValue, bitcast or "
-             "addrspacecast of GlobalValue",
-            &GA);
-
-    if (CE->getOpcode() == Instruction::BitCast) {
-      unsigned SrcAS = CE->getOperand(0)->getType()->getPointerAddressSpace();
-      unsigned DstAS = CE->getType()->getPointerAddressSpace();
-
-      Assert1(SrcAS == DstAS,
-              "Alias bitcasts cannot be between different address spaces",
-              &GA);
-    }
-  }
+  Assert1(isa<GlobalValue>(Aliasee) || isa<ConstantExpr>(Aliasee),
+          "Aliasee should be either GlobalValue or ConstantExpr", &GA);
 
-  const GlobalValue* Resolved = GA.resolveAliasedGlobal(/*stopOnWeak*/ false);
-  Assert1(Resolved,
-          "Aliasing chain should end with function or global variable", &GA);
+  visitAliaseeSubExpr(GA, *Aliasee);
 
   visitGlobalValue(GA);
 }
@@ -514,46 +587,92 @@ void Verifier::visitNamedMDNode(const NamedMDNode &NMD) {
     if (!MD)
       continue;
 
-    Assert1(!MD->isFunctionLocal(),
-            "Named metadata operand cannot be function local!", MD);
-    visitMDNode(*MD, 0);
+    visitMDNode(*MD);
   }
 }
 
-void Verifier::visitMDNode(MDNode &MD, Function *F) {
+void Verifier::visitMDNode(MDNode &MD) {
   // Only visit each node once.  Metadata can be mutually recursive, so this
   // avoids infinite recursion here, as well as being an optimization.
-  if (!MDNodes.insert(&MD))
+  if (!MDNodes.insert(&MD).second)
     return;
 
   for (unsigned i = 0, e = MD.getNumOperands(); i != e; ++i) {
-    Value *Op = MD.getOperand(i);
+    Metadata *Op = MD.getOperand(i);
     if (!Op)
       continue;
-    if (isa<Constant>(Op) || isa<MDString>(Op))
+    Assert2(!isa<LocalAsMetadata>(Op), "Invalid operand for global metadata!",
+            &MD, Op);
+    if (auto *N = dyn_cast<MDNode>(Op)) {
+      visitMDNode(*N);
       continue;
-    if (MDNode *N = dyn_cast<MDNode>(Op)) {
-      Assert2(MD.isFunctionLocal() || !N->isFunctionLocal(),
-              "Global metadata operand cannot be function local!", &MD, N);
-      visitMDNode(*N, F);
+    }
+    if (auto *V = dyn_cast<ValueAsMetadata>(Op)) {
+      visitValueAsMetadata(*V, nullptr);
       continue;
     }
-    Assert2(MD.isFunctionLocal(), "Invalid operand for global metadata!", &MD, Op);
-
-    // If this was an instruction, bb, or argument, verify that it is in the
-    // function that we expect.
-    Function *ActualF = 0;
-    if (Instruction *I = dyn_cast<Instruction>(Op))
-      ActualF = I->getParent()->getParent();
-    else if (BasicBlock *BB = dyn_cast<BasicBlock>(Op))
-      ActualF = BB->getParent();
-    else if (Argument *A = dyn_cast<Argument>(Op))
-      ActualF = A->getParent();
-    assert(ActualF && "Unimplemented function local metadata case!");
-
-    Assert2(ActualF == F, "function-local metadata used in wrong function",
-            &MD, Op);
   }
+
+  // Check these last, so we diagnose problems in operands first.
+  Assert1(!isa<MDNodeFwdDecl>(MD), "Expected no forward declarations!", &MD);
+  Assert1(MD.isResolved(), "All nodes should be resolved!", &MD);
+}
+
+void Verifier::visitValueAsMetadata(ValueAsMetadata &MD, Function *F) {
+  Assert1(MD.getValue(), "Expected valid value", &MD);
+  Assert2(!MD.getValue()->getType()->isMetadataTy(),
+          "Unexpected metadata round-trip through values", &MD, MD.getValue());
+
+  auto *L = dyn_cast<LocalAsMetadata>(&MD);
+  if (!L)
+    return;
+
+  Assert1(F, "function-local metadata used outside a function", L);
+
+  // If this was an instruction, bb, or argument, verify that it is in the
+  // function that we expect.
+  Function *ActualF = nullptr;
+  if (Instruction *I = dyn_cast<Instruction>(L->getValue())) {
+    Assert2(I->getParent(), "function-local metadata not in basic block", L, I);
+    ActualF = I->getParent()->getParent();
+  } else if (BasicBlock *BB = dyn_cast<BasicBlock>(L->getValue()))
+    ActualF = BB->getParent();
+  else if (Argument *A = dyn_cast<Argument>(L->getValue()))
+    ActualF = A->getParent();
+  assert(ActualF && "Unimplemented function local metadata case!");
+
+  Assert1(ActualF == F, "function-local metadata used in wrong function", L);
+}
+
+void Verifier::visitMetadataAsValue(MetadataAsValue &MDV, Function *F) {
+  Metadata *MD = MDV.getMetadata();
+  if (auto *N = dyn_cast<MDNode>(MD)) {
+    visitMDNode(*N);
+    return;
+  }
+
+  // Only visit each node once.  Metadata can be mutually recursive, so this
+  // avoids infinite recursion here, as well as being an optimization.
+  if (!MDNodes.insert(MD).second)
+    return;
+
+  if (auto *V = dyn_cast<ValueAsMetadata>(MD))
+    visitValueAsMetadata(*V, F);
+}
+
+void Verifier::visitComdat(const Comdat &C) {
+  // All Comdat::SelectionKind values other than Comdat::Any require a
+  // GlobalValue with the same name as the Comdat.
+  const GlobalValue *GV = M->getNamedValue(C.getName());
+  if (C.getSelectionKind() != Comdat::Any)
+    Assert1(GV,
+            "comdat selection kind requires a global value with the same name",
+            &C);
+  // The Module is invalid if the GlobalValue has private linkage.  Entities
+  // with private linkage don't have entries in the symbol table.
+  if (GV)
+    Assert1(!GV->hasPrivateLinkage(), "comdat global value has private linkage",
+            GV);
 }
 
 void Verifier::visitModuleIdents(const Module &M) {
@@ -589,7 +708,7 @@ void Verifier::visitModuleFlags(const Module &M) {
   for (unsigned I = 0, E = Requirements.size(); I != E; ++I) {
     const MDNode *Requirement = Requirements[I];
     const MDString *Flag = cast<MDString>(Requirement->getOperand(0));
-    const Value *ReqValue = Requirement->getOperand(1);
+    const Metadata *ReqValue = Requirement->getOperand(1);
 
     const MDNode *Op = SeenIDs.lookup(Flag);
     if (!Op) {
@@ -615,24 +734,23 @@ Verifier::visitModuleFlag(const MDNode *Op,
   // constant int), the flag ID (an MDString), and the value.
   Assert1(Op->getNumOperands() == 3,
           "incorrect number of operands in module flag", Op);
-  ConstantInt *Behavior = dyn_cast<ConstantInt>(Op->getOperand(0));
+  Module::ModFlagBehavior MFB;
+  if (!Module::isValidModFlagBehavior(Op->getOperand(0), MFB)) {
+    Assert1(
+        mdconst::dyn_extract<ConstantInt>(Op->getOperand(0)),
+        "invalid behavior operand in module flag (expected constant integer)",
+        Op->getOperand(0));
+    Assert1(false,
+            "invalid behavior operand in module flag (unexpected constant)",
+            Op->getOperand(0));
+  }
   MDString *ID = dyn_cast<MDString>(Op->getOperand(1));
-  Assert1(Behavior,
-          "invalid behavior operand in module flag (expected constant integer)",
-          Op->getOperand(0));
-  unsigned BehaviorValue = Behavior->getZExtValue();
   Assert1(ID,
           "invalid ID operand in module flag (expected metadata string)",
           Op->getOperand(1));
 
   // Sanity check the values for behaviors with additional requirements.
-  switch (BehaviorValue) {
-  default:
-    Assert1(false,
-            "invalid behavior operand in module flag (unexpected constant)",
-            Op->getOperand(0));
-    break;
-
+  switch (MFB) {
   case Module::Error:
   case Module::Warning:
   case Module::Override:
@@ -668,7 +786,7 @@ Verifier::visitModuleFlag(const MDNode *Op,
   }
 
   // Unless this is a "requires" flag, check the ID is unique.
-  if (BehaviorValue != Module::Require) {
+  if (MFB != Module::Require) {
     bool Inserted = SeenIDs.insert(std::make_pair(ID, Op)).second;
     Assert1(Inserted,
             "module flag identifiers must be unique (or of 'require' type)",
@@ -716,7 +834,8 @@ void Verifier::VerifyAttributeTypes(AttributeSet Attrs, unsigned Idx,
         I->getKindAsEnum() == Attribute::Builtin ||
         I->getKindAsEnum() == Attribute::NoBuiltin ||
         I->getKindAsEnum() == Attribute::Cold ||
-        I->getKindAsEnum() == Attribute::OptimizeNone) {
+        I->getKindAsEnum() == Attribute::OptimizeNone ||
+        I->getKindAsEnum() == Attribute::JumpTable) {
       if (!isFunction) {
         CheckFailed("Attribute '" + I->getAsString() +
                     "' only applies to functions!", V);
@@ -815,6 +934,7 @@ void Verifier::VerifyFunctionAttrs(FunctionType *FT, AttributeSet Attrs,
 
   bool SawNest = false;
   bool SawReturned = false;
+  bool SawSRet = false;
 
   for (unsigned i = 0, e = Attrs.getNumSlots(); i != e; ++i) {
     unsigned Idx = Attrs.getSlotIndex(i);
@@ -845,8 +965,12 @@ void Verifier::VerifyFunctionAttrs(FunctionType *FT, AttributeSet Attrs,
       SawReturned = true;
     }
 
-    if (Attrs.hasAttribute(Idx, Attribute::StructRet))
-      Assert1(Idx == 1, "Attribute sret is not on first parameter!", V);
+    if (Attrs.hasAttribute(Idx, Attribute::StructRet)) {
+      Assert1(!SawSRet, "Cannot have multiple 'sret' parameters!", V);
+      Assert1(Idx == 1 || Idx == 2,
+              "Attribute 'sret' is not on first or second parameter!", V);
+      SawSRet = true;
+    }
 
     if (Attrs.hasAttribute(Idx, Attribute::InAlloca)) {
       Assert1(Idx == FT->getNumParams(),
@@ -885,6 +1009,14 @@ void Verifier::VerifyFunctionAttrs(FunctionType *FT, AttributeSet Attrs,
                                 Attribute::MinSize),
             "Attributes 'minsize and optnone' are incompatible!", V);
   }
+
+  if (Attrs.hasAttribute(AttributeSet::FunctionIndex,
+                         Attribute::JumpTable)) {
+    const GlobalValue *GV = cast<GlobalValue>(V);
+    Assert1(GV->hasUnnamedAddr(),
+            "Attribute 'jumptable' requires 'unnamed_addr'", V);
+
+  }
 }
 
 void Verifier::VerifyBitcastType(const Value *V, Type *DestTy, Type *SrcTy) {
@@ -983,20 +1115,19 @@ void Verifier::visitFunction(const Function &F) {
           "Attribute 'builtin' can only be applied to a callsite.", &F);
 
   // Check that this function meets the restrictions on this calling convention.
+  // Sometimes varargs is used for perfectly forwarding thunks, so some of these
+  // restrictions can be lifted.
   switch (F.getCallingConv()) {
   default:
-    break;
   case CallingConv::C:
     break;
   case CallingConv::Fast:
   case CallingConv::Cold:
-  case CallingConv::X86_FastCall:
-  case CallingConv::X86_ThisCall:
   case CallingConv::Intel_OCL_BI:
   case CallingConv::PTX_Kernel:
   case CallingConv::PTX_Device:
-    Assert1(!F.isVarArg(),
-            "Varargs functions must have C calling conventions!", &F);
+    Assert1(!F.isVarArg(), "Calling convention does not support varargs or "
+                           "perfect forwarding!", &F);
     break;
   }
 
@@ -1104,6 +1235,12 @@ void Verifier::visitBasicBlock(BasicBlock &BB) {
       }
     }
   }
+
+  // Check that all instructions have their parent pointers set up correctly.
+  for (auto &I : BB)
+  {
+    Assert(I.getParent() == &BB, "Instruction has bogus parent pointer!");
+  }
 }
 
 void Verifier::visitTerminatorInst(TerminatorInst &I) {
@@ -1146,7 +1283,7 @@ void Verifier::visitSwitchInst(SwitchInst &SI) {
   for (SwitchInst::CaseIt i = SI.case_begin(), e = SI.case_end(); i != e; ++i) {
     Assert1(i.getCaseValue()->getType() == SwitchTy,
             "Switch constants must all be same type as switch value!", &SI);
-    Assert2(Constants.insert(i.getCaseValue()),
+    Assert2(Constants.insert(i.getCaseValue()).second,
             "Duplicate integer as switch case", &SI, i.getCaseValue());
   }
 
@@ -1483,6 +1620,16 @@ void Verifier::VerifyCallSite(CallSite CS) {
   // Verify call attributes.
   VerifyFunctionAttrs(FTy, Attrs, I);
 
+  // Conservatively check the inalloca argument.
+  // We have a bug if we can find that there is an underlying alloca without
+  // inalloca.
+  if (CS.hasInAllocaArgument()) {
+    Value *InAllocaArg = CS.getArgument(FTy->getNumParams() - 1);
+    if (auto AI = dyn_cast<AllocaInst>(InAllocaArg->stripInBoundsOffsets()))
+      Assert2(AI->isUsedWithInAlloca(),
+              "inalloca argument for call has mismatched alloca", AI, I);
+  }
+
   if (FTy->isVarArg()) {
     // FIXME? is 'nest' even legal here?
     bool SawNest = false;
@@ -1524,7 +1671,7 @@ void Verifier::VerifyCallSite(CallSite CS) {
   }
 
   // Verify that there's no metadata unless it's a direct call to an intrinsic.
-  if (CS.getCalledFunction() == 0 ||
+  if (CS.getCalledFunction() == nullptr ||
       !CS.getCalledFunction()->getName().startswith("llvm.")) {
     for (FunctionType::param_iterator PI = FTy->param_begin(),
            PE = FTy->param_end(); PI != PE; ++PI)
@@ -1535,9 +1682,102 @@ void Verifier::VerifyCallSite(CallSite CS) {
   visitInstruction(*I);
 }
 
+/// Two types are "congruent" if they are identical, or if they are both pointer
+/// types with different pointee types and the same address space.
+static bool isTypeCongruent(Type *L, Type *R) {
+  if (L == R)
+    return true;
+  PointerType *PL = dyn_cast<PointerType>(L);
+  PointerType *PR = dyn_cast<PointerType>(R);
+  if (!PL || !PR)
+    return false;
+  return PL->getAddressSpace() == PR->getAddressSpace();
+}
+
+static AttrBuilder getParameterABIAttributes(int I, AttributeSet Attrs) {
+  static const Attribute::AttrKind ABIAttrs[] = {
+      Attribute::StructRet, Attribute::ByVal, Attribute::InAlloca,
+      Attribute::InReg, Attribute::Returned};
+  AttrBuilder Copy;
+  for (auto AK : ABIAttrs) {
+    if (Attrs.hasAttribute(I + 1, AK))
+      Copy.addAttribute(AK);
+  }
+  if (Attrs.hasAttribute(I + 1, Attribute::Alignment))
+    Copy.addAlignmentAttr(Attrs.getParamAlignment(I + 1));
+  return Copy;
+}
+
+void Verifier::verifyMustTailCall(CallInst &CI) {
+  Assert1(!CI.isInlineAsm(), "cannot use musttail call with inline asm", &CI);
+
+  // - The caller and callee prototypes must match.  Pointer types of
+  //   parameters or return types may differ in pointee type, but not
+  //   address space.
+  Function *F = CI.getParent()->getParent();
+  auto GetFnTy = [](Value *V) {
+    return cast<FunctionType>(
+        cast<PointerType>(V->getType())->getElementType());
+  };
+  FunctionType *CallerTy = GetFnTy(F);
+  FunctionType *CalleeTy = GetFnTy(CI.getCalledValue());
+  Assert1(CallerTy->getNumParams() == CalleeTy->getNumParams(),
+          "cannot guarantee tail call due to mismatched parameter counts", &CI);
+  Assert1(CallerTy->isVarArg() == CalleeTy->isVarArg(),
+          "cannot guarantee tail call due to mismatched varargs", &CI);
+  Assert1(isTypeCongruent(CallerTy->getReturnType(), CalleeTy->getReturnType()),
+          "cannot guarantee tail call due to mismatched return types", &CI);
+  for (int I = 0, E = CallerTy->getNumParams(); I != E; ++I) {
+    Assert1(
+        isTypeCongruent(CallerTy->getParamType(I), CalleeTy->getParamType(I)),
+        "cannot guarantee tail call due to mismatched parameter types", &CI);
+  }
+
+  // - The calling conventions of the caller and callee must match.
+  Assert1(F->getCallingConv() == CI.getCallingConv(),
+          "cannot guarantee tail call due to mismatched calling conv", &CI);
+
+  // - All ABI-impacting function attributes, such as sret, byval, inreg,
+  //   returned, and inalloca, must match.
+  AttributeSet CallerAttrs = F->getAttributes();
+  AttributeSet CalleeAttrs = CI.getAttributes();
+  for (int I = 0, E = CallerTy->getNumParams(); I != E; ++I) {
+    AttrBuilder CallerABIAttrs = getParameterABIAttributes(I, CallerAttrs);
+    AttrBuilder CalleeABIAttrs = getParameterABIAttributes(I, CalleeAttrs);
+    Assert2(CallerABIAttrs == CalleeABIAttrs,
+            "cannot guarantee tail call due to mismatched ABI impacting "
+            "function attributes", &CI, CI.getOperand(I));
+  }
+
+  // - The call must immediately precede a :ref:`ret <i_ret>` instruction,
+  //   or a pointer bitcast followed by a ret instruction.
+  // - The ret instruction must return the (possibly bitcasted) value
+  //   produced by the call or void.
+  Value *RetVal = &CI;
+  Instruction *Next = CI.getNextNode();
+
+  // Handle the optional bitcast.
+  if (BitCastInst *BI = dyn_cast_or_null<BitCastInst>(Next)) {
+    Assert1(BI->getOperand(0) == RetVal,
+            "bitcast following musttail call must use the call", BI);
+    RetVal = BI;
+    Next = BI->getNextNode();
+  }
+
+  // Check the return.
+  ReturnInst *Ret = dyn_cast_or_null<ReturnInst>(Next);
+  Assert1(Ret, "musttail call must be precede a ret with an optional bitcast",
+          &CI);
+  Assert1(!Ret->getReturnValue() || Ret->getReturnValue() == RetVal,
+          "musttail call result must be returned", Ret);
+}
+
 void Verifier::visitCallInst(CallInst &CI) {
   VerifyCallSite(&CI);
 
+  if (CI.isMustTailCall())
+    verifyMustTailCall(CI);
+
   if (Function *F = CI.getCalledFunction())
     if (Intrinsic::ID ID = (Intrinsic::ID)F->getIntrinsicID())
       visitIntrinsicFunctionCall(ID, CI);
@@ -1712,12 +1952,65 @@ static bool isContiguous(const ConstantRange &A, const ConstantRange &B) {
   return A.getUpper() == B.getLower() || A.getLower() == B.getUpper();
 }
 
+void Verifier::visitRangeMetadata(Instruction& I,
+                                  MDNode* Range, Type* Ty) {
+  assert(Range &&
+         Range == I.getMetadata(LLVMContext::MD_range) &&
+         "precondition violation");
+
+  unsigned NumOperands = Range->getNumOperands();
+  Assert1(NumOperands % 2 == 0, "Unfinished range!", Range);
+  unsigned NumRanges = NumOperands / 2;
+  Assert1(NumRanges >= 1, "It should have at least one range!", Range);
+  
+  ConstantRange LastRange(1); // Dummy initial value
+  for (unsigned i = 0; i < NumRanges; ++i) {
+    ConstantInt *Low =
+        mdconst::dyn_extract<ConstantInt>(Range->getOperand(2 * i));
+    Assert1(Low, "The lower limit must be an integer!", Low);
+    ConstantInt *High =
+        mdconst::dyn_extract<ConstantInt>(Range->getOperand(2 * i + 1));
+    Assert1(High, "The upper limit must be an integer!", High);
+    Assert1(High->getType() == Low->getType() &&
+            High->getType() == Ty, "Range types must match instruction type!",
+            &I);
+    
+    APInt HighV = High->getValue();
+    APInt LowV = Low->getValue();
+    ConstantRange CurRange(LowV, HighV);
+    Assert1(!CurRange.isEmptySet() && !CurRange.isFullSet(),
+            "Range must not be empty!", Range);
+    if (i != 0) {
+      Assert1(CurRange.intersectWith(LastRange).isEmptySet(),
+              "Intervals are overlapping", Range);
+      Assert1(LowV.sgt(LastRange.getLower()), "Intervals are not in order",
+              Range);
+      Assert1(!isContiguous(CurRange, LastRange), "Intervals are contiguous",
+              Range);
+    }
+    LastRange = ConstantRange(LowV, HighV);
+  }
+  if (NumRanges > 2) {
+    APInt FirstLow =
+        mdconst::dyn_extract<ConstantInt>(Range->getOperand(0))->getValue();
+    APInt FirstHigh =
+        mdconst::dyn_extract<ConstantInt>(Range->getOperand(1))->getValue();
+    ConstantRange FirstRange(FirstLow, FirstHigh);
+    Assert1(FirstRange.intersectWith(LastRange).isEmptySet(),
+            "Intervals are overlapping", Range);
+    Assert1(!isContiguous(FirstRange, LastRange), "Intervals are contiguous",
+            Range);
+  }
+}
+
 void Verifier::visitLoadInst(LoadInst &LI) {
   PointerType *PTy = dyn_cast<PointerType>(LI.getOperand(0)->getType());
   Assert1(PTy, "Load operand must be a pointer.", &LI);
   Type *ElTy = PTy->getElementType();
   Assert2(ElTy == LI.getType(),
           "Load result type does not match pointer operand type!", &LI, ElTy);
+  Assert1(LI.getAlignment() <= Value::MaximumAlignment,
+          "huge alignment values are unsupported", &LI);
   if (LI.isAtomic()) {
     Assert1(LI.getOrdering() != Release && LI.getOrdering() != AcquireRelease,
             "Load cannot have Release ordering", &LI);
@@ -1725,11 +2018,11 @@ void Verifier::visitLoadInst(LoadInst &LI) {
             "Atomic load must specify explicit alignment", &LI);
     if (!ElTy->isPointerTy()) {
       Assert2(ElTy->isIntegerTy(),
-              "atomic store operand must have integer type!",
+              "atomic load operand must have integer type!",
               &LI, ElTy);
       unsigned Size = ElTy->getPrimitiveSizeInBits();
       Assert2(Size >= 8 && !(Size & (Size - 1)),
-              "atomic store operand must be power-of-two byte-sized integer",
+              "atomic load operand must be power-of-two byte-sized integer",
               &LI, ElTy);
     }
   } else {
@@ -1737,52 +2030,6 @@ void Verifier::visitLoadInst(LoadInst &LI) {
             "Non-atomic load cannot have SynchronizationScope specified", &LI);
   }
 
-  if (MDNode *Range = LI.getMetadata(LLVMContext::MD_range)) {
-    unsigned NumOperands = Range->getNumOperands();
-    Assert1(NumOperands % 2 == 0, "Unfinished range!", Range);
-    unsigned NumRanges = NumOperands / 2;
-    Assert1(NumRanges >= 1, "It should have at least one range!", Range);
-
-    ConstantRange LastRange(1); // Dummy initial value
-    for (unsigned i = 0; i < NumRanges; ++i) {
-      ConstantInt *Low = dyn_cast<ConstantInt>(Range->getOperand(2*i));
-      Assert1(Low, "The lower limit must be an integer!", Low);
-      ConstantInt *High = dyn_cast<ConstantInt>(Range->getOperand(2*i + 1));
-      Assert1(High, "The upper limit must be an integer!", High);
-      Assert1(High->getType() == Low->getType() &&
-              High->getType() == ElTy, "Range types must match load type!",
-              &LI);
-
-      APInt HighV = High->getValue();
-      APInt LowV = Low->getValue();
-      ConstantRange CurRange(LowV, HighV);
-      Assert1(!CurRange.isEmptySet() && !CurRange.isFullSet(),
-              "Range must not be empty!", Range);
-      if (i != 0) {
-        Assert1(CurRange.intersectWith(LastRange).isEmptySet(),
-                "Intervals are overlapping", Range);
-        Assert1(LowV.sgt(LastRange.getLower()), "Intervals are not in order",
-                Range);
-        Assert1(!isContiguous(CurRange, LastRange), "Intervals are contiguous",
-                Range);
-      }
-      LastRange = ConstantRange(LowV, HighV);
-    }
-    if (NumRanges > 2) {
-      APInt FirstLow =
-        dyn_cast<ConstantInt>(Range->getOperand(0))->getValue();
-      APInt FirstHigh =
-        dyn_cast<ConstantInt>(Range->getOperand(1))->getValue();
-      ConstantRange FirstRange(FirstLow, FirstHigh);
-      Assert1(FirstRange.intersectWith(LastRange).isEmptySet(),
-              "Intervals are overlapping", Range);
-      Assert1(!isContiguous(FirstRange, LastRange), "Intervals are contiguous",
-              Range);
-    }
-
-
-  }
-
   visitInstruction(LI);
 }
 
@@ -1793,6 +2040,8 @@ void Verifier::visitStoreInst(StoreInst &SI) {
   Assert2(ElTy == SI.getOperand(0)->getType(),
           "Stored value type does not match pointer operand type!",
           &SI, ElTy);
+  Assert1(SI.getAlignment() <= Value::MaximumAlignment,
+          "huge alignment values are unsupported", &SI);
   if (SI.isAtomic()) {
     Assert1(SI.getOrdering() != Acquire && SI.getOrdering() != AcquireRelease,
             "Store cannot have Acquire ordering", &SI);
@@ -1824,15 +2073,30 @@ void Verifier::visitAllocaInst(AllocaInst &AI) {
           &AI);
   Assert1(AI.getArraySize()->getType()->isIntegerTy(),
           "Alloca array size must have integer type", &AI);
+  Assert1(AI.getAlignment() <= Value::MaximumAlignment,
+          "huge alignment values are unsupported", &AI);
 
   visitInstruction(AI);
 }
 
 void Verifier::visitAtomicCmpXchgInst(AtomicCmpXchgInst &CXI) {
-  Assert1(CXI.getOrdering() != NotAtomic,
+
+  // FIXME: more conditions???
+  Assert1(CXI.getSuccessOrdering() != NotAtomic,
+          "cmpxchg instructions must be atomic.", &CXI);
+  Assert1(CXI.getFailureOrdering() != NotAtomic,
           "cmpxchg instructions must be atomic.", &CXI);
-  Assert1(CXI.getOrdering() != Unordered,
+  Assert1(CXI.getSuccessOrdering() != Unordered,
+          "cmpxchg instructions cannot be unordered.", &CXI);
+  Assert1(CXI.getFailureOrdering() != Unordered,
           "cmpxchg instructions cannot be unordered.", &CXI);
+  Assert1(CXI.getSuccessOrdering() >= CXI.getFailureOrdering(),
+          "cmpxchg instructions be at least as constrained on success as fail",
+          &CXI);
+  Assert1(CXI.getFailureOrdering() != Release &&
+              CXI.getFailureOrdering() != AcquireRelease,
+          "cmpxchg failure ordering cannot include release semantics", &CXI);
+
   PointerType *PTy = dyn_cast<PointerType>(CXI.getOperand(0)->getType());
   Assert1(PTy, "First cmpxchg operand must be a pointer.", &CXI);
   Type *ElTy = PTy->getElementType();
@@ -1937,8 +2201,7 @@ void Verifier::visitLandingPadInst(LandingPadInst &LPI) {
   Assert1(isa<Constant>(PersonalityFn), "Personality function is not constant!",
           &LPI);
   for (unsigned i = 0, e = LPI.getNumClauses(); i < e; ++i) {
-    Value *Clause = LPI.getClause(i);
-    Assert1(isa<Constant>(Clause), "Clause is not constant!", &LPI);
+    Constant *Clause = LPI.getClause(i);
     if (LPI.isCatch(i)) {
       Assert1(isa<PointerType>(Clause->getType()),
               "Catch operand does not have pointer type!", &LPI);
@@ -1974,10 +2237,10 @@ void Verifier::visitInstruction(Instruction &I) {
   Assert1(BB, "Instruction not embedded in basic block!", &I);
 
   if (!isa<PHINode>(I)) {   // Check that non-phi nodes are not self referential
-    for (Value::use_iterator UI = I.use_begin(), UE = I.use_end();
-         UI != UE; ++UI)
-      Assert1(*UI != (User*)&I || !DT.isReachableFromEntry(BB),
+    for (User *U : I.users()) {
+      Assert1(U != (User*)&I || !DT.isReachableFromEntry(BB),
               "Only PHI nodes may reference their own value!", &I);
+    }
   }
 
   // Check that void typed values don't have names
@@ -1999,19 +2262,18 @@ void Verifier::visitInstruction(Instruction &I) {
   // Check that all uses of the instruction, if they are instructions
   // themselves, actually have parent basic blocks.  If the use is not an
   // instruction, it is an error!
-  for (User::use_iterator UI = I.use_begin(), UE = I.use_end();
-       UI != UE; ++UI) {
-    if (Instruction *Used = dyn_cast<Instruction>(*UI))
-      Assert2(Used->getParent() != 0, "Instruction referencing instruction not"
-              " embedded in a basic block!", &I, Used);
+  for (Use &U : I.uses()) {
+    if (Instruction *Used = dyn_cast<Instruction>(U.getUser()))
+      Assert2(Used->getParent() != nullptr, "Instruction referencing"
+              " instruction not embedded in a basic block!", &I, Used);
     else {
-      CheckFailed("Use of instruction is not an instruction!", *UI);
+      CheckFailed("Use of instruction is not an instruction!", U);
       return;
     }
   }
 
   for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i) {
-    Assert1(I.getOperand(i) != 0, "Instruction has null operand!", &I);
+    Assert1(I.getOperand(i) != nullptr, "Instruction has null operand!", &I);
 
     // Check to make sure that only first-class-values are operands to
     // instructions.
@@ -2022,11 +2284,15 @@ void Verifier::visitInstruction(Instruction &I) {
     if (Function *F = dyn_cast<Function>(I.getOperand(i))) {
       // Check to make sure that the "address of" an intrinsic function is never
       // taken.
-      Assert1(!F->isIntrinsic() || i == (isa<CallInst>(I) ? e-1 : 0),
+      Assert1(!F->isIntrinsic() || i == (isa<CallInst>(I) ? e-1 :
+                                         isa<InvokeInst>(I) ? e-3 : 0),
               "Cannot take the address of an intrinsic!", &I);
       Assert1(!F->isIntrinsic() || isa<CallInst>(I) ||
-              F->getIntrinsicID() == Intrinsic::donothing,
-              "Cannot invoke an intrinsinc other than donothing", &I);
+              F->getIntrinsicID() == Intrinsic::donothing ||
+              F->getIntrinsicID() == Intrinsic::experimental_patchpoint_void ||
+              F->getIntrinsicID() == Intrinsic::experimental_patchpoint_i64,
+              "Cannot invoke an intrinsinc other than"
+              " donothing or patchpoint", &I);
       Assert1(F->getParent() == M, "Referencing function in another module!",
               &I);
     } else if (BasicBlock *OpBB = dyn_cast<BasicBlock>(I.getOperand(i))) {
@@ -2054,7 +2320,7 @@ void Verifier::visitInstruction(Instruction &I) {
 
         while (!Stack.empty()) {
           const ConstantExpr *V = Stack.pop_back_val();
-          if (!Visited.insert(V))
+          if (!Visited.insert(V).second)
             continue;
 
           VerifyConstantExprBitcastType(V);
@@ -2072,8 +2338,8 @@ void Verifier::visitInstruction(Instruction &I) {
     Assert1(I.getType()->isFPOrFPVectorTy(),
             "fpmath requires a floating point result!", &I);
     Assert1(MD->getNumOperands() == 1, "fpmath takes one operand!", &I);
-    Value *Op0 = MD->getOperand(0);
-    if (ConstantFP *CFP0 = dyn_cast_or_null<ConstantFP>(Op0)) {
+    if (ConstantFP *CFP0 =
+            mdconst::dyn_extract_or_null<ConstantFP>(MD->getOperand(0))) {
       APFloat Accuracy = CFP0->getValueAPF();
       Assert1(Accuracy.isFiniteNonZero() && !Accuracy.isNegative(),
               "fpmath accuracy not a positive number!", &I);
@@ -2082,12 +2348,18 @@ void Verifier::visitInstruction(Instruction &I) {
     }
   }
 
-  MDNode *MD = I.getMetadata(LLVMContext::MD_range);
-  Assert1(!MD || isa<LoadInst>(I), "Ranges are only for loads!", &I);
+  if (MDNode *Range = I.getMetadata(LLVMContext::MD_range)) {
+    Assert1(isa<LoadInst>(I) || isa<CallInst>(I) || isa<InvokeInst>(I),
+            "Ranges are only for loads, calls and invokes!", &I);
+    visitRangeMetadata(I, Range, I.getType());
+  }
 
-  if (!DisableDebugInfoVerifier) {
-    MD = I.getMetadata(LLVMContext::MD_dbg);
-    Finder.processLocation(*M, DILocation(MD));
+  if (I.getMetadata(LLVMContext::MD_nonnull)) {
+    Assert1(I.getType()->isPointerTy(),
+            "nonnull applies only to pointer types", &I);
+    Assert1(isa<LoadInst>(I),
+            "nonnull applies only to load instructions, use attributes"
+            " for calls or invokes", &I);
   }
 
   InstsInThisBlock.insert(&I);
@@ -2119,18 +2391,18 @@ bool Verifier::VerifyIntrinsicType(Type *Ty,
   case IITDescriptor::Integer: return !Ty->isIntegerTy(D.Integer_Width);
   case IITDescriptor::Vector: {
     VectorType *VT = dyn_cast<VectorType>(Ty);
-    return VT == 0 || VT->getNumElements() != D.Vector_Width ||
+    return !VT || VT->getNumElements() != D.Vector_Width ||
            VerifyIntrinsicType(VT->getElementType(), Infos, ArgTys);
   }
   case IITDescriptor::Pointer: {
     PointerType *PT = dyn_cast<PointerType>(Ty);
-    return PT == 0 || PT->getAddressSpace() != D.Pointer_AddressSpace ||
+    return !PT || PT->getAddressSpace() != D.Pointer_AddressSpace ||
            VerifyIntrinsicType(PT->getElementType(), Infos, ArgTys);
   }
 
   case IITDescriptor::Struct: {
     StructType *ST = dyn_cast<StructType>(Ty);
-    if (ST == 0 || ST->getNumElements() != D.Struct_NumElements)
+    if (!ST || ST->getNumElements() != D.Struct_NumElements)
       return true;
 
     for (unsigned i = 0, e = D.Struct_NumElements; i != e; ++i)
@@ -2158,19 +2430,55 @@ bool Verifier::VerifyIntrinsicType(Type *Ty,
     }
     llvm_unreachable("all argument kinds not covered");
 
-  case IITDescriptor::ExtendVecArgument:
+  case IITDescriptor::ExtendArgument: {
     // This may only be used when referring to a previous vector argument.
-    return D.getArgumentNumber() >= ArgTys.size() ||
-           !isa<VectorType>(ArgTys[D.getArgumentNumber()]) ||
-           VectorType::getExtendedElementVectorType(
-                       cast<VectorType>(ArgTys[D.getArgumentNumber()])) != Ty;
+    if (D.getArgumentNumber() >= ArgTys.size())
+      return true;
+
+    Type *NewTy = ArgTys[D.getArgumentNumber()];
+    if (VectorType *VTy = dyn_cast<VectorType>(NewTy))
+      NewTy = VectorType::getExtendedElementVectorType(VTy);
+    else if (IntegerType *ITy = dyn_cast<IntegerType>(NewTy))
+      NewTy = IntegerType::get(ITy->getContext(), 2 * ITy->getBitWidth());
+    else
+      return true;
+
+    return Ty != NewTy;
+  }
+  case IITDescriptor::TruncArgument: {
+    // This may only be used when referring to a previous vector argument.
+    if (D.getArgumentNumber() >= ArgTys.size())
+      return true;
+
+    Type *NewTy = ArgTys[D.getArgumentNumber()];
+    if (VectorType *VTy = dyn_cast<VectorType>(NewTy))
+      NewTy = VectorType::getTruncatedElementVectorType(VTy);
+    else if (IntegerType *ITy = dyn_cast<IntegerType>(NewTy))
+      NewTy = IntegerType::get(ITy->getContext(), ITy->getBitWidth() / 2);
+    else
+      return true;
 
-  case IITDescriptor::TruncVecArgument:
+    return Ty != NewTy;
+  }
+  case IITDescriptor::HalfVecArgument:
     // This may only be used when referring to a previous vector argument.
     return D.getArgumentNumber() >= ArgTys.size() ||
            !isa<VectorType>(ArgTys[D.getArgumentNumber()]) ||
-           VectorType::getTruncatedElementVectorType(
+           VectorType::getHalfElementsVectorType(
                          cast<VectorType>(ArgTys[D.getArgumentNumber()])) != Ty;
+  case IITDescriptor::SameVecWidthArgument: {
+    if (D.getArgumentNumber() >= ArgTys.size())
+      return true;
+    VectorType * ReferenceType =
+      dyn_cast<VectorType>(ArgTys[D.getArgumentNumber()]);
+    VectorType *ThisArgType = dyn_cast<VectorType>(Ty);
+    if (!ThisArgType || !ReferenceType || 
+        (ReferenceType->getVectorNumElements() !=
+         ThisArgType->getVectorNumElements()))
+      return true;
+    return VerifyIntrinsicType(ThisArgType->getVectorElementType(),
+                               Infos, ArgTys);
+  }
   }
   llvm_unreachable("unhandled");
 }
@@ -2240,14 +2548,16 @@ void Verifier::visitIntrinsicFunctionCall(Intrinsic::ID ID, CallInst &CI) {
   // know they are legal for the intrinsic!) get the intrinsic name through the
   // usual means.  This allows us to verify the mangling of argument types into
   // the name.
-  Assert1(Intrinsic::getName(ID, ArgTys) == IF->getName(),
-          "Intrinsic name not mangled correctly for type arguments!", IF);
+  const std::string ExpectedName = Intrinsic::getName(ID, ArgTys);
+  Assert1(ExpectedName == IF->getName(),
+          "Intrinsic name not mangled correctly for type arguments! "
+          "Should be: " + ExpectedName, IF);
 
   // If the intrinsic takes MDNode arguments, verify that they are either global
   // or are local to *this* function.
   for (unsigned i = 0, e = CI.getNumArgOperands(); i != e; ++i)
-    if (MDNode *MD = dyn_cast<MDNode>(CI.getArgOperand(i)))
-      visitMDNode(*MD, CI.getParent()->getParent());
+    if (auto *MD = dyn_cast<MetadataAsValue>(CI.getArgOperand(i)))
+      visitMetadataAsValue(*MD, CI.getParent()->getParent());
 
   switch (ID) {
   default:
@@ -2259,22 +2569,9 @@ void Verifier::visitIntrinsicFunctionCall(Intrinsic::ID ID, CallInst &CI) {
             "constant int", &CI);
     break;
   case Intrinsic::dbg_declare: {  // llvm.dbg.declare
-    Assert1(CI.getArgOperand(0) && isa<MDNode>(CI.getArgOperand(0)),
-                "invalid llvm.dbg.declare intrinsic call 1", &CI);
-    MDNode *MD = cast<MDNode>(CI.getArgOperand(0));
-    Assert1(MD->getNumOperands() == 1,
-                "invalid llvm.dbg.declare intrinsic call 2", &CI);
-    if (!DisableDebugInfoVerifier)
-      Finder.processDeclare(*M, cast<DbgDeclareInst>(&CI));
+    Assert1(CI.getArgOperand(0) && isa<MetadataAsValue>(CI.getArgOperand(0)),
+            "invalid llvm.dbg.declare intrinsic call 1", &CI);
   } break;
-  case Intrinsic::dbg_value: { //llvm.dbg.value
-    if (!DisableDebugInfoVerifier) {
-      Assert1(CI.getArgOperand(0) && isa<MDNode>(CI.getArgOperand(0)),
-              "invalid llvm.dbg.value intrinsic call 1", &CI);
-      Finder.processValue(*M, cast<DbgValueInst>(&CI));
-    }
-    break;
-  }
   case Intrinsic::memcpy:
   case Intrinsic::memmove:
   case Intrinsic::memset:
@@ -2333,31 +2630,203 @@ void Verifier::visitIntrinsicFunctionCall(Intrinsic::ID ID, CallInst &CI) {
     Assert1(isa<ConstantInt>(CI.getArgOperand(1)),
             "llvm.invariant.end parameter #2 must be a constant integer", &CI);
     break;
+ 
+  case Intrinsic::experimental_gc_statepoint: {
+    Assert1(!CI.doesNotAccessMemory() &&
+            !CI.onlyReadsMemory(),
+            "gc.statepoint must read and write memory to preserve "
+            "reordering restrictions required by safepoint semantics", &CI);
+    Assert1(!CI.isInlineAsm(),
+            "gc.statepoint support for inline assembly unimplemented", &CI);
+    
+    const Value *Target = CI.getArgOperand(0);
+    const PointerType *PT = dyn_cast<PointerType>(Target->getType());
+    Assert2(PT && PT->getElementType()->isFunctionTy(),
+            "gc.statepoint callee must be of function pointer type",
+            &CI, Target);
+    FunctionType *TargetFuncType = cast<FunctionType>(PT->getElementType());
+    Assert1(!TargetFuncType->isVarArg(),
+            "gc.statepoint support for var arg functions not implemented", &CI);
+
+    const Value *NumCallArgsV = CI.getArgOperand(1);
+    Assert1(isa<ConstantInt>(NumCallArgsV),
+            "gc.statepoint number of arguments to underlying call "
+            "must be constant integer", &CI);
+    const int NumCallArgs = cast<ConstantInt>(NumCallArgsV)->getZExtValue();
+    Assert1(NumCallArgs >= 0,
+            "gc.statepoint number of arguments to underlying call "
+            "must be positive", &CI);
+    Assert1(NumCallArgs == (int)TargetFuncType->getNumParams(),
+            "gc.statepoint mismatch in number of call args", &CI);
+
+    const Value *Unused = CI.getArgOperand(2);
+    Assert1(isa<ConstantInt>(Unused) &&
+            cast<ConstantInt>(Unused)->isNullValue(),
+            "gc.statepoint parameter #3 must be zero", &CI);
+
+    // Verify that the types of the call parameter arguments match
+    // the type of the wrapped callee.
+    for (int i = 0; i < NumCallArgs; i++) {
+      Type *ParamType = TargetFuncType->getParamType(i);
+      Type *ArgType = CI.getArgOperand(3+i)->getType();
+      Assert1(ArgType == ParamType,
+              "gc.statepoint call argument does not match wrapped "
+              "function type", &CI);
+    }
+    const int EndCallArgsInx = 2+NumCallArgs;
+    const Value *NumDeoptArgsV = CI.getArgOperand(EndCallArgsInx+1);
+    Assert1(isa<ConstantInt>(NumDeoptArgsV),
+            "gc.statepoint number of deoptimization arguments "
+            "must be constant integer", &CI);
+    const int NumDeoptArgs = cast<ConstantInt>(NumDeoptArgsV)->getZExtValue();
+    Assert1(NumDeoptArgs >= 0,
+            "gc.statepoint number of deoptimization arguments "
+            "must be positive", &CI);
+
+    Assert1(4 + NumCallArgs + NumDeoptArgs <= (int)CI.getNumArgOperands(),
+            "gc.statepoint too few arguments according to length fields", &CI);
+    
+    // Check that the only uses of this gc.statepoint are gc.result or 
+    // gc.relocate calls which are tied to this statepoint and thus part
+    // of the same statepoint sequence
+    for (User *U : CI.users()) {
+      const CallInst *Call = dyn_cast<const CallInst>(U);
+      Assert2(Call, "illegal use of statepoint token", &CI, U);
+      if (!Call) continue;
+      Assert2(isGCRelocate(Call) || isGCResult(Call),
+              "gc.result or gc.relocate are the only value uses"
+              "of a gc.statepoint", &CI, U);
+      if (isGCResult(Call)) {
+        Assert2(Call->getArgOperand(0) == &CI,
+                "gc.result connected to wrong gc.statepoint",
+                &CI, Call);
+      } else if (isGCRelocate(Call)) {
+        Assert2(Call->getArgOperand(0) == &CI,
+                "gc.relocate connected to wrong gc.statepoint",
+                &CI, Call);
+      }
+    }
+
+    // Note: It is legal for a single derived pointer to be listed multiple
+    // times.  It's non-optimal, but it is legal.  It can also happen after
+    // insertion if we strip a bitcast away.
+    // Note: It is really tempting to check that each base is relocated and
+    // that a derived pointer is never reused as a base pointer.  This turns
+    // out to be problematic since optimizations run after safepoint insertion
+    // can recognize equality properties that the insertion logic doesn't know
+    // about.  See example statepoint.ll in the verifier subdirectory
+    break;
+  }
+  case Intrinsic::experimental_gc_result_int:
+  case Intrinsic::experimental_gc_result_float:
+  case Intrinsic::experimental_gc_result_ptr: {
+    // Are we tied to a statepoint properly?
+    CallSite StatepointCS(CI.getArgOperand(0));
+    const Function *StatepointFn = StatepointCS.getCalledFunction();
+    Assert2(StatepointFn && StatepointFn->isDeclaration() &&
+            StatepointFn->getIntrinsicID() == Intrinsic::experimental_gc_statepoint,
+            "token must be from a statepoint", &CI, CI.getArgOperand(0));
+
+    // Assert that result type matches wrapped callee.
+    const Value *Target = StatepointCS.getArgument(0);
+    const PointerType *PT = cast<PointerType>(Target->getType());
+    const FunctionType *TargetFuncType =
+      cast<FunctionType>(PT->getElementType());
+    Assert1(CI.getType() == TargetFuncType->getReturnType(),
+            "gc.result result type does not match wrapped callee",
+            &CI);
+    break;
+  }
+  case Intrinsic::experimental_gc_relocate: {
+    // Are we tied to a statepoint properly?
+    CallSite StatepointCS(CI.getArgOperand(0));
+    const Function *StatepointFn =
+        StatepointCS.getInstruction() ? StatepointCS.getCalledFunction() : NULL;
+    Assert2(StatepointFn && StatepointFn->isDeclaration() &&
+            StatepointFn->getIntrinsicID() == Intrinsic::experimental_gc_statepoint,
+            "token must be from a statepoint", &CI, CI.getArgOperand(0));
+
+    // Both the base and derived must be piped through the safepoint
+    Value* Base = CI.getArgOperand(1);
+    Assert1( isa<ConstantInt>(Base), "must be integer offset", &CI);
+    
+    Value* Derived = CI.getArgOperand(2);
+    Assert1( isa<ConstantInt>(Derived), "must be integer offset", &CI);
+
+    const int BaseIndex = cast<ConstantInt>(Base)->getZExtValue();
+    const int DerivedIndex = cast<ConstantInt>(Derived)->getZExtValue();
+    // Check the bounds
+    Assert1(0 <= BaseIndex &&
+            BaseIndex < (int)StatepointCS.arg_size(),
+            "index out of bounds", &CI);
+    Assert1(0 <= DerivedIndex &&
+            DerivedIndex < (int)StatepointCS.arg_size(),
+            "index out of bounds", &CI);
+
+    // Assert that the result type matches the type of the relocated pointer
+    GCRelocateOperands Operands(&CI);
+    Assert1(Operands.derivedPtr()->getType() == CI.getType(),
+            "gc.relocate: relocating a pointer shouldn't change it's type",
+            &CI);
+    break;
   }
+  };
 }
 
-void Verifier::verifyDebugInfo() {
+void DebugInfoVerifier::verifyDebugInfo() {
+  if (!VerifyDebugInfo)
+    return;
+
+  DebugInfoFinder Finder;
+  Finder.processModule(*M);
+  processInstructions(Finder);
+
   // Verify Debug Info.
-  if (!DisableDebugInfoVerifier) {
-    for (DebugInfoFinder::iterator I = Finder.compile_unit_begin(),
-         E = Finder.compile_unit_end(); I != E; ++I)
-      Assert1(DICompileUnit(*I).Verify(), "DICompileUnit does not Verify!", *I);
-    for (DebugInfoFinder::iterator I = Finder.subprogram_begin(),
-         E = Finder.subprogram_end(); I != E; ++I)
-      Assert1(DISubprogram(*I).Verify(), "DISubprogram does not Verify!", *I);
-    for (DebugInfoFinder::iterator I = Finder.global_variable_begin(),
-         E = Finder.global_variable_end(); I != E; ++I)
-      Assert1(DIGlobalVariable(*I).Verify(),
-              "DIGlobalVariable does not Verify!", *I);
-    for (DebugInfoFinder::iterator I = Finder.type_begin(),
-         E = Finder.type_end(); I != E; ++I)
-      Assert1(DIType(*I).Verify(), "DIType does not Verify!", *I);
-    for (DebugInfoFinder::iterator I = Finder.scope_begin(),
-         E = Finder.scope_end(); I != E; ++I)
-      Assert1(DIScope(*I).Verify(), "DIScope does not Verify!", *I);
+  //
+  // NOTE:  The loud braces are necessary for MSVC compatibility.
+  for (DICompileUnit CU : Finder.compile_units()) {
+    Assert1(CU.Verify(), "DICompileUnit does not Verify!", CU);
+  }
+  for (DISubprogram S : Finder.subprograms()) {
+    Assert1(S.Verify(), "DISubprogram does not Verify!", S);
+  }
+  for (DIGlobalVariable GV : Finder.global_variables()) {
+    Assert1(GV.Verify(), "DIGlobalVariable does not Verify!", GV);
+  }
+  for (DIType T : Finder.types()) {
+    Assert1(T.Verify(), "DIType does not Verify!", T);
+  }
+  for (DIScope S : Finder.scopes()) {
+    Assert1(S.Verify(), "DIScope does not Verify!", S);
   }
 }
 
+void DebugInfoVerifier::processInstructions(DebugInfoFinder &Finder) {
+  for (const Function &F : *M)
+    for (auto I = inst_begin(&F), E = inst_end(&F); I != E; ++I) {
+      if (MDNode *MD = I->getMetadata(LLVMContext::MD_dbg))
+        Finder.processLocation(*M, DILocation(MD));
+      if (const CallInst *CI = dyn_cast<CallInst>(&*I))
+        processCallInst(Finder, *CI);
+    }
+}
+
+void DebugInfoVerifier::processCallInst(DebugInfoFinder &Finder,
+                                        const CallInst &CI) {
+  if (Function *F = CI.getCalledFunction())
+    if (Intrinsic::ID ID = (Intrinsic::ID)F->getIntrinsicID())
+      switch (ID) {
+      case Intrinsic::dbg_declare:
+        Finder.processDeclare(*M, cast<DbgDeclareInst>(&CI));
+        break;
+      case Intrinsic::dbg_value:
+        Finder.processValue(*M, cast<DbgValueInst>(&CI));
+        break;
+      default:
+        break;
+      }
+}
+
 //===----------------------------------------------------------------------===//
 //  Implement the public interfaces to this file...
 //===----------------------------------------------------------------------===//
@@ -2380,12 +2849,13 @@ bool llvm::verifyModule(const Module &M, raw_ostream *OS) {
 
   bool Broken = false;
   for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
-    if (!I->isDeclaration())
+    if (!I->isDeclaration() && !I->isMaterializable())
       Broken |= !V.verify(*I);
 
   // Note that this function's return value is inverted from what you would
   // expect of a function called "verify".
-  return !V.verify(M) || Broken;
+  DebugInfoVerifier DIV(OS ? *OS : NullStr);
+  return !V.verify(M) || !DIV.verify(M) || Broken;
 }
 
 namespace {
@@ -2421,15 +2891,48 @@ struct VerifierLegacyPass : public FunctionPass {
     AU.setPreservesAll();
   }
 };
+struct DebugInfoVerifierLegacyPass : public ModulePass {
+  static char ID;
+
+  DebugInfoVerifier V;
+  bool FatalErrors;
+
+  DebugInfoVerifierLegacyPass() : ModulePass(ID), FatalErrors(true) {
+    initializeDebugInfoVerifierLegacyPassPass(*PassRegistry::getPassRegistry());
+  }
+  explicit DebugInfoVerifierLegacyPass(bool FatalErrors)
+      : ModulePass(ID), V(dbgs()), FatalErrors(FatalErrors) {
+    initializeDebugInfoVerifierLegacyPassPass(*PassRegistry::getPassRegistry());
+  }
+
+  bool runOnModule(Module &M) override {
+    if (!V.verify(M) && FatalErrors)
+      report_fatal_error("Broken debug info found, compilation aborted!");
+
+    return false;
+  }
+
+  void getAnalysisUsage(AnalysisUsage &AU) const override {
+    AU.setPreservesAll();
+  }
+};
 }
 
 char VerifierLegacyPass::ID = 0;
 INITIALIZE_PASS(VerifierLegacyPass, "verify", "Module Verifier", false, false)
 
+char DebugInfoVerifierLegacyPass::ID = 0;
+INITIALIZE_PASS(DebugInfoVerifierLegacyPass, "verify-di", "Debug Info Verifier",
+                false, false)
+
 FunctionPass *llvm::createVerifierPass(bool FatalErrors) {
   return new VerifierLegacyPass(FatalErrors);
 }
 
+ModulePass *llvm::createDebugInfoVerifierPass(bool FatalErrors) {
+  return new DebugInfoVerifierLegacyPass(FatalErrors);
+}
+
 PreservedAnalyses VerifierPass::run(Module *M) {
   if (verifyModule(*M, &dbgs()) && FatalErrors)
     report_fatal_error("Broken module found, compilation aborted!");