Introduce the notion of function addresses in Subzero.

src/PNaClTranslator.cpp

 //===- subzero/src/PNaClTranslator.cpp - ICE from bitcode -----------------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the PNaCl bitcode file to Ice, to machine code
 // translator.
 //
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Analysis/NaCl/PNaClABIProps.h"
 #include "llvm/Bitcode/NaCl/NaClBitcodeDecoders.h"
 #include "llvm/Bitcode/NaCl/NaClBitcodeHeader.h"
 #include "llvm/Bitcode/NaCl/NaClBitcodeParser.h"
 #include "llvm/Bitcode/NaCl/NaClReaderWriter.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Module.h"
 #include "llvm/Support/Format.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/Support/ValueHandle.h"
 
 #include "IceCfg.h"
 #include "IceCfgNode.h"
 #include "IceClFlags.h"
 #include "IceDefs.h"
 #include "IceGlobalInits.h"
 #include "IceInst.h"
 #include "IceOperand.h"
 #include "IceTypeConverter.h"
 #include "PNaClTranslator.h"
@@ skipping 115 matching lines @@
     break;
   }
 }
 
 // Top-level class to read PNaCl bitcode files, and translate to ICE.
 class TopLevelParser : public NaClBitcodeParser {
   TopLevelParser(const TopLevelParser &) = delete;
   TopLevelParser &operator=(const TopLevelParser &) = delete;
 
 public:
+  typedef std::vector<Ice::Function *> FunctionListType;
+
   TopLevelParser(Ice::Translator &Translator, const std::string &InputName,
                  NaClBitcodeHeader &Header, NaClBitstreamCursor &Cursor,
                  bool &ErrorStatus)
       : NaClBitcodeParser(Cursor), Translator(Translator),
         Mod(new Module(InputName, getGlobalContext())), DL(PNaClDataLayout),
-        Header(Header), TypeConverter(getLLVMContext()),
+        Header(Header), TypeConverter(Mod->getContext()),
         ErrorStatus(ErrorStatus), NumErrors(0), NumFunctionIds(0),
         NumFunctionBlocks(0) {
     Mod->setDataLayout(PNaClDataLayout);
     setErrStream(Translator.getContext()->getStrDump());
   }
 
-  ~TopLevelParser() override { DeleteContainerPointers(GlobalIDAddresses); }
+  ~TopLevelParser() override {}
 
   Ice::Translator &getTranslator() { return Translator; }
 
   // Generates error with given Message. Always returns true.
   bool Error(const std::string &Message) override {
     ErrorStatus = true;
     ++NumErrors;
     NaClBitcodeParser::Error(Message);
     if (!AllowErrorRecovery)
       report_fatal_error("Unable to continue");
     return true;
   }
 
   /// Returns the number of errors found while parsing the bitcode
   /// file.
   unsigned getNumErrors() const { return NumErrors; }
 
   /// Returns the LLVM module associated with the translation.
   Module *getModule() const { return Mod.get(); }
 
   const DataLayout &getDataLayout() const { return DL; }
 
   /// Returns the number of bytes in the bitcode header.
   size_t getHeaderSize() const { return Header.getHeaderSize(); }
 
-  /// Returns the llvm context to use.
-  LLVMContext &getLLVMContext() const { return Mod->getContext(); }
-
   /// Changes the size of the type list to the given size.
   void resizeTypeIDValues(unsigned NewSize) { TypeIDValues.resize(NewSize); }
 
   /// Returns the undefined type associated with type ID.
   /// Note: Returns extended type ready to be defined.
   ExtendedType *getTypeByIDForDefining(unsigned ID) {
     // Get corresponding element, verifying the value is still undefined
     // (and hence allowed to be defined).
     ExtendedType *Ty = getTypeByIDAsKind(ID, ExtendedType::Undefined);
     if (Ty)
@@ skipping 15 matching lines @@
   /// Returns the type signature associated with the given index.
   const Ice::FuncSigType &getFuncSigTypeByID(unsigned ID) {
     const ExtendedType *Ty = getTypeByIDAsKind(ID, ExtendedType::FuncSig);
     if (Ty == nullptr)
       // Return error recovery value.
       return UndefinedFuncSigType;
     return cast<FuncSigExtendedType>(Ty)->getSignature();
   }
 
   /// Sets the next function ID to the given LLVM function.
-  void setNextFunctionID(Function *Fcn) {
+  void setNextFunctionID(Ice::Function *Fcn) {
     ++NumFunctionIds;
-    FunctionIDValues.push_back(Fcn);
+    FunctionList.push_back(Fcn);
   }
 
   /// Defines the next function ID as one that has an implementation
   /// (i.e a corresponding function block in the bitcode).
   void setNextValueIDAsImplementedFunction() {
-    DefiningFunctionsList.push_back(FunctionIDValues.size());
+    DefiningFunctionsList.push_back(FunctionList.size());
   }
 
   /// Returns the value id that should be associated with the the
   /// current function block. Increments internal counters during call
   /// so that it will be in correct position for next function block.
   unsigned getNextFunctionBlockValueID() {
     if (NumFunctionBlocks >= DefiningFunctionsList.size())
       report_fatal_error(
           "More function blocks than defined function addresses");
     return DefiningFunctionsList[NumFunctionBlocks++];
   }
 
-  /// Returns the LLVM Function address associated with ID.
-  Function *getFunctionByID(unsigned ID) const {
-    if (ID >= FunctionIDValues.size())
-      return nullptr;
-    Value *V = FunctionIDValues[ID];
-    return cast<Function>(V);
+  /// Returns the function associated with ID.
+  Ice::Function *getFunctionByID(unsigned ID) {
+    if (ID < FunctionList.size())
+      return FunctionList[ID];
+    return reportGetFunctionByIDError(ID);
   }
 
+  /// Returns the list of function addresses.
+  const FunctionListType &getFunctionList() { return FunctionList; }

[jvoung (off chromium), 2014/10/10 01:47:28]

const ?

[Karl, 2014/10/10 20:17:30]

Done.

+
   /// Returns the corresponding constant associated with a global value
   /// (i.e. relocatable).
   Ice::Constant *getOrCreateGlobalConstantByID(unsigned ID) {
     // TODO(kschimpf): Can this be built when creating global initializers?
     Ice::Constant *C;
     if (ID >= ValueIDConstants.size()) {
       C = nullptr;
-      unsigned ExpectedSize =
-          FunctionIDValues.size() + GlobalIDAddresses.size();
+      unsigned ExpectedSize = FunctionList.size() + GlobalVariables.size();
       if (ID >= ExpectedSize)
         ExpectedSize = ID;
       ValueIDConstants.resize(ExpectedSize);
     } else {
       C = ValueIDConstants[ID];
     }
     if (C != nullptr)
       return C;
 
     // If reached, no such constant exists, create one.
     std::string Name;
-    unsigned FcnIDSize = FunctionIDValues.size();
+    unsigned FcnIDSize = FunctionList.size();
     if (ID < FcnIDSize) {
-      Name = FunctionIDValues[ID]->getName();
-    } else if ((ID - FcnIDSize) < GlobalIDAddresses.size()) {
-      Name = GlobalIDAddresses[ID - FcnIDSize]->getName();
+      Name = FunctionList[ID]->getName();
+    } else if ((ID - FcnIDSize) < GlobalVariables.size()) {
+      Name = GlobalVariables[ID - FcnIDSize]->getName();
     } else {
       std::string Buffer;
       raw_string_ostream StrBuf(Buffer);
       StrBuf << "Reference to global not defined: " << ID;
       Error(StrBuf.str());
       Name = "??";
     }
     const uint64_t Offset = 0;
     C = getTranslator().getContext()->getConstantSym(
         getIcePointerType(), Offset, Name);
     ValueIDConstants[ID] = C;
     return C;
   }
 
   /// Returns the number of function addresses (i.e. ID's) defined in
   /// the bitcode file.
   unsigned getNumFunctionIDs() const { return NumFunctionIds; }
 
   /// Returns the number of global IDs (function and global addresses)
   /// defined in the bitcode file.
   unsigned getNumGlobalIDs() const {
-    return FunctionIDValues.size() + GlobalIDAddresses.size();
+    return FunctionList.size() + GlobalVariables.size();
   }
 
   /// Creates Count global addresses.
-  void CreateGlobalAddresses(size_t Count) {
-    assert(GlobalIDAddresses.empty());
+  void CreateGlobalVariables(size_t Count) {
+    assert(GlobalVariables.empty());
+    Ice::GlobalContext *Context = getTranslator().getContext();
     for (size_t i = 0; i < Count; ++i) {
-      GlobalIDAddresses.push_back(new Ice::GlobalAddress());
+      GlobalVariables.push_back(Ice::GlobalVariable::create(Context));
     }
   }
 
   /// Returns the number of global addresses (i.e. ID's) defined in
   /// the bitcode file.
-  Ice::SizeT getNumGlobalAddresses() const { return GlobalIDAddresses.size(); }
+  Ice::SizeT getNumGlobalVariables() const { return GlobalVariables.size(); }
 
   /// Returns the global address with the given index.
-  Ice::GlobalAddress *getGlobalAddress(size_t Index) {
-    if (Index < GlobalIDAddresses.size())
-      return GlobalIDAddresses[Index];
-    std::string Buffer;
-    raw_string_ostream StrBuf(Buffer);
-    StrBuf << "Global index " << Index
-           << " not allowed. Out of range. Must be less than "
-           << GlobalIDAddresses.size();
-    Error(StrBuf.str());
-    // TODO(kschimpf) Remove error recovery once implementation complete.
-    if (!GlobalIDAddresses.empty())
-      return GlobalIDAddresses[0];
-    report_fatal_error("Unable to continue");
+  Ice::GlobalVariable *getGlobalVariableByID(unsigned Index) {
+    if (Index < GlobalVariables.size())
+      return GlobalVariables[Index];
+    return reportGetGlobalVariableByIDError(Index);
+  }
+
+  /// Returns the global address (variable or function) with the given Index.
+  Ice::GlobalAddress *getGlobalAddressByID(size_t Index) {
+    if (Index < NumFunctionIds)
+      return getFunctionByID(Index);
+    else
+      return getGlobalVariableByID(Index - NumFunctionIds);
   }
 
   /// Returns the list of read global addresses.
-  const Ice::Translator::GlobalAddressList &getGlobalIDAddresses() {
-    return GlobalIDAddresses;
+  const Ice::Translator::GlobalVariableListType &getGlobalVariables() {
+    return GlobalVariables;
   }
 
   /// Returns the corresponding ICE type for LLVMTy.
   Ice::Type convertToIceType(Type *LLVMTy) {
     Ice::Type IceTy = TypeConverter.convertToIceType(LLVMTy);
     if (IceTy >= Ice::IceType_NUM) {
       return convertToIceTypeError(LLVMTy);
     }
     return IceTy;
   }
@@ skipping 18 matching lines @@
   // The bitcode header.
   NaClBitcodeHeader &Header;
   // Converter between LLVM and ICE types.
   Ice::TypeConverter TypeConverter;
   // The exit status that should be set to true if an error occurs.
   bool &ErrorStatus;
   // The number of errors reported.
   unsigned NumErrors;
   // The types associated with each type ID.
   std::vector<ExtendedType> TypeIDValues;
-  // The set of function value IDs.
-  std::vector<WeakVH> FunctionIDValues;
-  // The set of global addresses IDs.
-  Ice::Translator::GlobalAddressList GlobalIDAddresses;
-  // Relocatable constants associated with FunctionIDValues and
-  // GlobalIDAddresses.
+  // The set of functions.
+  FunctionListType FunctionList;
+  // The set of global variables.
+  Ice::Translator::GlobalVariableListType GlobalVariables;
+  // Relocatable constants associated with FunctionList and
+  // GlobalVariables.
   std::vector<Ice::Constant *> ValueIDConstants;
   // The number of function IDs.
   unsigned NumFunctionIds;
   // The number of function blocks (processed so far).
   unsigned NumFunctionBlocks;
   // The list of value IDs (in the order found) of defining function
   // addresses.
+  // TODO(kschimpf): Instead of using this list, just use FunctionList,
+  // and the isProto member function.
   std::vector<unsigned> DefiningFunctionsList;
   // Error recovery value to use when getFuncSigTypeByID fails.
   Ice::FuncSigType UndefinedFuncSigType;
 
   bool ParseBlock(unsigned BlockID) override;
 
   // Gets extended type associated with the given index, assuming the
   // extended type is of the WantedKind. Generates error message if
   // corresponding extended type of WantedKind can't be found, and
   // returns nullptr.
   ExtendedType *getTypeByIDAsKind(unsigned ID,
                                   ExtendedType::TypeKind WantedKind) {
     ExtendedType *Ty = nullptr;
     if (ID < TypeIDValues.size()) {
       Ty = &TypeIDValues[ID];
       if (Ty->getKind() == WantedKind)
         return Ty;
     }
     // Generate an error message and set ErrorStatus.
     this->reportBadTypeIDAs(ID, Ty, WantedKind);
     return nullptr;
   }
 
   // Reports that type ID is undefined, or not of the WantedType.
   void reportBadTypeIDAs(unsigned ID, const ExtendedType *Ty,
                          ExtendedType::TypeKind WantedType);
 
+  // Reports that there is no function address for ID. Returns

[Jim Stichnoth, 2014/10/10 13:15:00]

fill-paragraph?

[Karl, 2014/10/10 20:17:30]

Done.

+  // an error recovery value to use.
+  Ice::Function *reportGetFunctionByIDError(unsigned ID);
+
+  // Reports that there is not global variable address for ID. Returns
+  // an error recovery value to use.
+  Ice::GlobalVariable *reportGetGlobalVariableByIDError(unsigned Index);
+
   // Reports that there is no corresponding ICE type for LLVMTy, and
   // returns ICE::IceType_void.
   Ice::Type convertToIceTypeError(Type *LLVMTy);
 };
 
 void TopLevelParser::reportBadTypeIDAs(unsigned ID, const ExtendedType *Ty,
                                        ExtendedType::TypeKind WantedType) {
   std::string Buffer;
   raw_string_ostream StrBuf(Buffer);
   if (Ty == nullptr) {
     StrBuf << "Can't find extended type for type id: " << ID;
   } else {
     StrBuf << "Type id " << ID << " not " << WantedType << ". Found: " << *Ty;
   }
   Error(StrBuf.str());
 }
 
+Ice::Function *TopLevelParser::reportGetFunctionByIDError(unsigned ID) {
+  std::string Buffer;
+  raw_string_ostream StrBuf(Buffer);
+  StrBuf << "Function index " << ID
+         << " not allowed. Out of range. Must be less than "
+         << FunctionList.size();
+  Error(StrBuf.str());
+  // TODO(kschimpf) Remove error recovery once implementation complete.
+  if (!FunctionList.empty())
+    return FunctionList[0];
+  report_fatal_error("Unable to continue");
+}
+
+Ice::GlobalVariable *
+TopLevelParser::reportGetGlobalVariableByIDError(unsigned Index) {
+  std::string Buffer;
+  raw_string_ostream StrBuf(Buffer);
+  StrBuf << "Global index " << Index
+         << " not allowed. Out of range. Must be less than "
+         << GlobalVariables.size();
+  Error(StrBuf.str());
+  // TODO(kschimpf) Remove error recovery once implementation complete.
+  if (!GlobalVariables.empty())
+    return GlobalVariables[0];
+  report_fatal_error("Unable to continue");
+}
+
 Ice::Type TopLevelParser::convertToIceTypeError(Type *LLVMTy) {
   std::string Buffer;
   raw_string_ostream StrBuf(Buffer);
   StrBuf << "Invalid LLVM type: " << *LLVMTy;
   Error(StrBuf.str());
   return Ice::IceType_void;
 }
 
 // Base class for parsing blocks within the bitcode file.  Note:
 // Because this is the base class of block parsers, we generate error
@@ skipping 292 matching lines @@
     return;
   }
   llvm_unreachable("Unknown type block record not processed!");
 }
 
 /// Parses the globals block (i.e. global variables).
 class GlobalsParser : public BlockParserBaseClass {
 public:
   GlobalsParser(unsigned BlockID, BlockParserBaseClass *EnclosingParser)
       : BlockParserBaseClass(BlockID, EnclosingParser), InitializersNeeded(0),
-        NextGlobalID(0), CurrentAddress(&DummyAddress) {}
-
-  ~GlobalsParser() override {}
+        NextGlobalID(0), DummyGlobalVar(Ice::GlobalVariable::create(
+                             getTranslator().getContext())),
+        CurGlobalVar(DummyGlobalVar) {}
 
 private:
   // Keeps track of how many initializers are expected for the global variable
   // being built.
   unsigned InitializersNeeded;
 
   // The index of the next global variable.
   unsigned NextGlobalID;
 
-  // Holds the current global address whose initializer is being defined.
-  Ice::GlobalAddress *CurrentAddress;
+  // Dummy global variable to guarantee CurGlobalVar is always defined
+  // (allowing code to not need to check if CurGlobalVar is nullptr).
+  Ice::GlobalVariable *DummyGlobalVar;
 
-  // Dummy global address to guarantee CurrentAddress is always defined
-  // (allowing code to not need to check if CurrentAddress is nullptr).
-  Ice::GlobalAddress DummyAddress;
+  // Holds the current global variable being built.
+  Ice::GlobalVariable *CurGlobalVar;
 
   void ExitBlock() override {
     verifyNoMissingInitializers();
-    unsigned NumIDs = Context->getNumGlobalAddresses();
+    unsigned NumIDs = Context->getNumGlobalVariables();
     if (NextGlobalID < NumIDs) {
       std::string Buffer;
       raw_string_ostream StrBuf(Buffer);
       StrBuf << "Globals block expects " << NumIDs
              << " global definitions. Found: " << NextGlobalID;
       Error(StrBuf.str());
     }
     BlockParserBaseClass::ExitBlock();
   }
 
   void ProcessRecord() override;
 
-  // Checks if the number of initializers for the CurrentAddress is the same as
+  // Checks if the number of initializers for the CurGlobalVar is the same as
   // the number found in the bitcode file. If different, and error message is
   // generated, and the internal state of the parser is fixed so this condition
   // is no longer violated.
   void verifyNoMissingInitializers() {
-    size_t NumInits = CurrentAddress->getInitializers().size();
+    size_t NumInits = CurGlobalVar->getInitializers().size();
     if (InitializersNeeded != NumInits) {
       std::string Buffer;
       raw_string_ostream StrBuf(Buffer);
       StrBuf << "Global variable @g" << NextGlobalID << " expected "
              << InitializersNeeded << " initializer";
       if (InitializersNeeded > 1)
         StrBuf << "s";
       StrBuf << ". Found: " << NumInits;
       Error(StrBuf.str());
     }
   }
 };
 
 void GlobalsParser::ProcessRecord() {
   const NaClBitcodeRecord::RecordVector &Values = Record.GetValues();
   switch (Record.GetCode()) {
   case naclbitc::GLOBALVAR_COUNT:
     // COUNT: [n]
     if (!isValidRecordSize(1, "Globals count"))
       return;
-    if (NextGlobalID != Context->getNumGlobalAddresses()) {
+    if (NextGlobalID != Context->getNumGlobalVariables()) {
       Error("Globals count record not first in block.");
       return;
     }
-    Context->CreateGlobalAddresses(Values[0]);
+    Context->CreateGlobalVariables(Values[0]);
     return;
   case naclbitc::GLOBALVAR_VAR: {
     // VAR: [align, isconst]
     if (!isValidRecordSize(2, "Globals variable"))
       return;
     verifyNoMissingInitializers();
     InitializersNeeded = 1;
-    CurrentAddress = Context->getGlobalAddress(NextGlobalID);
-    CurrentAddress->setAlignment((1 << Values[0]) >> 1);
-    CurrentAddress->setIsConstant(Values[1] != 0);
+    CurGlobalVar = Context->getGlobalVariableByID(NextGlobalID);
+    CurGlobalVar->setAlignment((1 << Values[0]) >> 1);
+    CurGlobalVar->setIsConstant(Values[1] != 0);
     ++NextGlobalID;
     return;
   }
   case naclbitc::GLOBALVAR_COMPOUND:
     // COMPOUND: [size]
     if (!isValidRecordSize(1, "globals compound"))
       return;
-    if (!CurrentAddress->getInitializers().empty()) {
+    if (!CurGlobalVar->getInitializers().empty()) {
       Error("Globals compound record not first initializer");
       return;
     }
     if (Values[0] < 2) {
       std::string Buffer;
       raw_string_ostream StrBuf(Buffer);
       StrBuf << "Globals compound record size invalid. Found: " << Values[0];
       Error(StrBuf.str());
       return;
     }
     InitializersNeeded = Values[0];
     return;
   case naclbitc::GLOBALVAR_ZEROFILL: {
     // ZEROFILL: [size]
     if (!isValidRecordSize(1, "Globals zerofill"))
       return;
-    CurrentAddress->addInitializer(
-        new Ice::GlobalAddress::ZeroInitializer(Values[0]));
-    break;
+    CurGlobalVar->addInitializer(
+        new Ice::GlobalVariable::ZeroInitializer(Values[0]));
+    return;
   }
   case naclbitc::GLOBALVAR_DATA: {
     // DATA: [b0, b1, ...]
     if (!isValidRecordSizeAtLeast(1, "Globals data"))
       return;
-    CurrentAddress->addInitializer(
-        new Ice::GlobalAddress::DataInitializer(Values));
-    break;
+    CurGlobalVar->addInitializer(
+        new Ice::GlobalVariable::DataInitializer(Values));
+    return;
   }
   case naclbitc::GLOBALVAR_RELOC: {
     // RELOC: [val, [addend]]
     if (!isValidRecordSizeInRange(1, 2, "Globals reloc"))
       return;
     unsigned Index = Values[0];
     Ice::SizeT Offset = 0;
     if (Values.size() == 2)
       Offset = Values[1];
-    unsigned NumFunctions = Context->getNumFunctionIDs();
-    if (Index < NumFunctions) {
-      llvm::Function *Fcn = Context->getFunctionByID(Index);
-      Ice::GlobalAddress::RelocationAddress Addr(Fcn);
-      CurrentAddress->addInitializer(
-          new Ice::GlobalAddress::RelocInitializer(Addr, Offset));
-    } else {
-      Ice::GlobalAddress::RelocationAddress Addr(
-          Context->getGlobalAddress(Index - NumFunctions));
-      CurrentAddress->addInitializer(
-          new Ice::GlobalAddress::RelocInitializer(Addr, Offset));
-    }
-    break;
+    CurGlobalVar->addInitializer(new Ice::GlobalVariable::RelocInitializer(
+        Context->getGlobalAddressByID(Index), Offset));
+    return;
   }
   default:
     BlockParserBaseClass::ProcessRecord();
     return;
   }
 }
 
 /// Base class for parsing a valuesymtab block in the bitcode file.
 class ValuesymtabParser : public BlockParserBaseClass {
   ValuesymtabParser(const ValuesymtabParser &) = delete;
@@ skipping 60 matching lines @@
 class FunctionParser : public BlockParserBaseClass {
   FunctionParser(const FunctionParser &) = delete;
   FunctionParser &operator=(const FunctionParser &) = delete;
   friend class FunctionValuesymtabParser;
 
 public:
   FunctionParser(unsigned BlockID, BlockParserBaseClass *EnclosingParser)
       : BlockParserBaseClass(BlockID, EnclosingParser),
         Func(new Ice::Cfg(getTranslator().getContext())), CurrentBbIndex(0),
         FcnId(Context->getNextFunctionBlockValueID()),
-        LLVMFunc(Context->getFunctionByID(FcnId)),
+        FuncDecl(Context->getFunctionByID(FcnId)),
         CachedNumGlobalValueIDs(Context->getNumGlobalIDs()),
         NextLocalInstIndex(Context->getNumGlobalIDs()),
         InstIsTerminating(false) {
-    Func->setFunctionName(LLVMFunc->getName());
+    Func->setFunctionName(FuncDecl->getName());
     if (getFlags().TimeEachFunction)
       getTranslator().getContext()->pushTimer(
           getTranslator().getContext()->getTimerID(
               Ice::GlobalContext::TSK_Funcs, Func->getFunctionName()),
           Ice::GlobalContext::TSK_Funcs);
-    Func->setReturnType(Context->convertToIceType(LLVMFunc->getReturnType()));
-    Func->setInternal(LLVMFunc->hasInternalLinkage());
+    // TODO(kschimpf) Clean up API to add a function signature to
+    // a CFG.
+    const Ice::FuncSigType &Signature = FuncDecl->getSignature();
+    Func->setReturnType(Signature.getReturnType());
+    Func->setInternal(FuncDecl->getLinkage() == GlobalValue::InternalLinkage);
     CurrentNode = InstallNextBasicBlock();
     Func->setEntryNode(CurrentNode);
-    for (auto ArgI = LLVMFunc->arg_begin(), ArgE = LLVMFunc->arg_end();
-         ArgI != ArgE; ++ArgI) {
-      Func->addArg(getNextInstVar(Context->convertToIceType(ArgI->getType())));
+    for (Ice::Type ArgType : Signature.getArgList()) {
+      Func->addArg(getNextInstVar(ArgType));
     }
   }
 
   ~FunctionParser() override {};
 
   // Set the next constant ID to the given constant C.
   void setNextConstantID(Ice::Constant *C) {
     setOperand(NextLocalInstIndex++, C);
   }
 
 private:
   // The corresponding ICE function defined by the function block.
   Ice::Cfg *Func;
   // The index to the current basic block being built.
   uint32_t CurrentBbIndex;
   // The basic block being built.
   Ice::CfgNode *CurrentNode;
   // The ID for the function.
   unsigned FcnId;
-  // The corresponding LLVM function.
-  Function *LLVMFunc;
+  // The corresponding function declaration.
+  Ice::Function *FuncDecl;
   // Holds the dividing point between local and global absolute value indices.
   uint32_t CachedNumGlobalValueIDs;
   // Holds operands local to the function block, based on indices
   // defined in the bitcode file.
   std::vector<Ice::Operand *> LocalOperands;
   // Holds the index within LocalOperands corresponding to the next
   // instruction that generates a value.
   uint32_t NextLocalInstIndex;
   // True if the last processed instruction was a terminating
   // instruction.
@@ skipping 1012 matching lines @@
       return;
     }
     bool IsTailCall = static_cast<bool>(CCInfo & 1);
 
     // Extract out the called function and its return type.
     uint32_t CalleeIndex = convertRelativeToAbsIndex(Values[1], BaseIndex);
     Ice::Operand *Callee = getOperand(CalleeIndex);
     Ice::Type ReturnType = Ice::IceType_void;
     const Ice::Intrinsics::FullIntrinsicInfo *IntrinsicInfo = nullptr;
     if (Record.GetCode() == naclbitc::FUNC_CODE_INST_CALL) {
-      Function *Fcn = Context->getFunctionByID(CalleeIndex);
-      if (Fcn == nullptr) {
-        std::string Buffer;
-        raw_string_ostream StrBuf(Buffer);
-        StrBuf << "Function call to non-function: " << *Callee;
-        Error(StrBuf.str());
-        return;
-      }
-
-      FunctionType *FcnTy = Fcn->getFunctionType();
-      ReturnType = Context->convertToIceType(FcnTy->getReturnType());
+      Ice::Function *Fcn = Context->getFunctionByID(CalleeIndex);
+      const Ice::FuncSigType &Signature = Fcn->getSignature();
+      ReturnType = Signature.getReturnType();
 
       // Check if this direct call is to an Intrinsic (starts with "llvm.")
       static Ice::IceString LLVMPrefix("llvm.");
       Ice::IceString Name = Fcn->getName();
       if (isStringPrefix(Name, LLVMPrefix)) {
         Ice::IceString Suffix = Name.substr(LLVMPrefix.size());
         IntrinsicInfo =
             getTranslator().getContext()->getIntrinsicsInfo().find(Suffix);
         if (!IntrinsicInfo) {
           std::string Buffer;
@@ skipping 283 matching lines @@
       : BlockParserBaseClass(BlockID, Context),
         GlobalAddressNamesAndInitializersInstalled(false) {}
 
   ~ModuleParser() override {}
 
 private:
   // True if we have already instaledl names for unnamed global addresses,
   // and generated global constant initializers.
   bool GlobalAddressNamesAndInitializersInstalled;
 
-  // Generates names for unnamed global addresses, and lowers global
-  // constant initializers to the target. May be called multiple
-  // times. Only the first call will do the installation.
-  void InstallGlobalAddressNamesAndInitializers() {
+  // Generates names for unnamed global addresses (i.e. functions and
+  // global variables). Then lowers global variable initializers to
+  // the target. May be called multiple times. Only the first call
+  // will do the installation.
+  void InstallGlobalNamesAndGlobalVarInitializers() {
     if (!GlobalAddressNamesAndInitializersInstalled) {
       Ice::Translator &Trans = getTranslator();
       const Ice::IceString &GlobalPrefix = getFlags().DefaultGlobalPrefix;
       if (!GlobalPrefix.empty()) {
         uint32_t NameIndex = 0;
-        for (Ice::GlobalAddress *Address : Context->getGlobalIDAddresses()) {
-          if (!Address->hasName()) {
-            Address->setName(Trans.createUnnamedName(GlobalPrefix, NameIndex));
-            ++NameIndex;
-          } else {
-            Trans.checkIfUnnamedNameSafe(Address->getName(), "global",
-                                         GlobalPrefix,
-                                         Trans.getContext()->getStrDump());
-          }
+        for (Ice::GlobalVariable *Vbl : Context->getGlobalVariables()) {
+          installAddressName(Trans, Vbl, GlobalPrefix, "global", NameIndex);
         }
       }
-      Trans.nameUnnamedFunctions(Context->getModule());
-      getTranslator().lowerGlobals(Context->getGlobalIDAddresses());
+      const Ice::IceString &FunctionPrefix = getFlags().DefaultFunctionPrefix;
+      if (!FunctionPrefix.empty()) {
+        uint32_t NameIndex = 0;
+        for (Ice::Function *Func : Context->getFunctionList()) {
+          installAddressName(Trans, Func, FunctionPrefix, "function",
+                             NameIndex);
+        }
+      }
+      getTranslator().lowerGlobals(Context->getGlobalVariables());
       GlobalAddressNamesAndInitializersInstalled = true;
     }
   }
 
+  void installAddressName(Ice::Translator &Trans, Ice::GlobalAddress *Address,
+                          const Ice::IceString &Prefix, const char *Context,
+                          uint32_t &NameIndex) {
+    if (!Address->hasName()) {
+      Address->setName(Trans.createUnnamedName(Prefix, NameIndex));
+      ++NameIndex;
+    } else {
+      Trans.checkIfUnnamedNameSafe(Address->getName(), Context, Prefix,
+                                   Trans.getContext()->getStrDump());
+    }
+  }
+
   bool ParseBlock(unsigned BlockID) override;
 
   void ExitBlock() override {
-    InstallGlobalAddressNamesAndInitializers();
+    InstallGlobalNamesAndGlobalVarInitializers();
     getTranslator().emitConstants();
   }
 
   void ProcessRecord() override;
 };
 
 class ModuleValuesymtabParser : public ValuesymtabParser {
   ModuleValuesymtabParser(const ModuleValuesymtabParser &) = delete;
   void operator=(const ModuleValuesymtabParser &) = delete;
 
 public:
   ModuleValuesymtabParser(unsigned BlockID, ModuleParser *MP)
       : ValuesymtabParser(BlockID, MP) {}
 
   ~ModuleValuesymtabParser() override {}
 
 private:
   void setValueName(uint64_t Index, StringType &Name) override;
   void setBbName(uint64_t Index, StringType &Name) override;
 };
 
 void ModuleValuesymtabParser::setValueName(uint64_t Index, StringType &Name) {
-  if (Index < Context->getNumFunctionIDs()) {
-    Function *Fcn = Context->getFunctionByID(Index);
-    if (Fcn != nullptr) {
-      Fcn->setName(StringRef(Name.data(), Name.size()));
-      return;
-    }
-  } else {
-    unsigned NumFunctions = Context->getNumFunctionIDs();
-    if (Index >= NumFunctions) {
-      Context->getGlobalAddress(Index - NumFunctions)
-          ->setName(StringRef(Name.data(), Name.size()));
-    }
-    return;
-  }
-
-  std::string Buffer;
-  raw_string_ostream StrBuf(Buffer);
-  StrBuf << "Invalid global address ID in valuesymtab: " << Index;
-  Error(StrBuf.str());
-  return;
+  Context->getGlobalAddressByID(Index)
+      ->setName(StringRef(Name.data(), Name.size()));
 }
 
 void ModuleValuesymtabParser::setBbName(uint64_t Index, StringType &Name) {
   std::string Buffer;
   raw_string_ostream StrBuf(Buffer);
   StrBuf << "Can't define basic block name at global level: '" << Name
          << "' -> " << Index;
   Error(StrBuf.str());
 }
 
 bool ModuleParser::ParseBlock(unsigned BlockID) {
   switch (BlockID) {
   case naclbitc::BLOCKINFO_BLOCK_ID:
     return NaClBitcodeParser::ParseBlock(BlockID);
   case naclbitc::TYPE_BLOCK_ID_NEW: {
     TypesParser Parser(BlockID, this);
     return Parser.ParseThisBlock();
   }
   case naclbitc::GLOBALVAR_BLOCK_ID: {
     GlobalsParser Parser(BlockID, this);
     return Parser.ParseThisBlock();
   }
   case naclbitc::VALUE_SYMTAB_BLOCK_ID: {
     ModuleValuesymtabParser Parser(BlockID, this);
     return Parser.ParseThisBlock();
   }
   case naclbitc::FUNCTION_BLOCK_ID: {
-    InstallGlobalAddressNamesAndInitializers();
+    InstallGlobalNamesAndGlobalVarInitializers();
     FunctionParser Parser(BlockID, this);
     return Parser.ParseThisBlock();
   }
   default:
     return BlockParserBaseClass::ParseBlock(BlockID);
   }
 }
 
 void ModuleParser::ProcessRecord() {
   const NaClBitcodeRecord::RecordVector &Values = Record.GetValues();
   switch (Record.GetCode()) {
   case naclbitc::MODULE_CODE_VERSION: {
     // VERSION: [version#]
     if (!isValidRecordSize(1, "Module version"))
       return;
     unsigned Version = Values[0];
     if (Version != 1) {
       std::string Buffer;
       raw_string_ostream StrBuf(Buffer);
       StrBuf << "Unknown bitstream version: " << Version;
       Error(StrBuf.str());
     }
     return;
   }
   case naclbitc::MODULE_CODE_FUNCTION: {
     // FUNCTION:  [type, callingconv, isproto, linkage]
     if (!isValidRecordSize(4, "Function heading"))
       return;
-    const Ice::FuncSigType &Ty = Context->getFuncSigTypeByID(Values[0]);
+    const Ice::FuncSigType &Signature = Context->getFuncSigTypeByID(Values[0]);
     CallingConv::ID CallingConv;
     if (!naclbitc::DecodeCallingConv(Values[1], CallingConv)) {
       std::string Buffer;
       raw_string_ostream StrBuf(Buffer);
       StrBuf << "Function heading has unknown calling convention: "
              << Values[1];
       Error(StrBuf.str());
       return;
     }
     GlobalValue::LinkageTypes Linkage;
     if (!naclbitc::DecodeLinkage(Values[3], Linkage)) {
       std::string Buffer;
       raw_string_ostream StrBuf(Buffer);
       StrBuf << "Function heading has unknown linkage. Found " << Values[3];
       Error(StrBuf.str());
       return;
     }
-    SmallVector<Type *, 8> ArgTys;
-    for (Ice::Type ArgType : Ty.getArgList()) {
-      ArgTys.push_back(Context->convertToLLVMType(ArgType));
-    }
-    Function *Func = Function::Create(
-        FunctionType::get(Context->convertToLLVMType(Ty.getReturnType()),
-                          ArgTys, false),
-        Linkage, "", Context->getModule());
-    Func->setCallingConv(CallingConv);
+    Ice::Function *Func =
+        Ice::Function::create(getTranslator().getContext(), Signature,
+                              CallingConv, Linkage, Values[2] == 0);
     if (Values[2] == 0)
       Context->setNextValueIDAsImplementedFunction();
     Context->setNextFunctionID(Func);
-    // TODO(kschimpf) verify if Func matches PNaCl ABI.
     return;
   }
   default:
     BlockParserBaseClass::ProcessRecord();
     return;
   }
 }
 
 bool TopLevelParser::ParseBlock(unsigned BlockID) {
   if (BlockID == naclbitc::MODULE_BLOCK_ID) {
@@ skipping 53 matching lines @@
 
   if (TopLevelBlocks != 1) {
     errs() << IRFilename
            << ": Contains more than one module. Found: " << TopLevelBlocks
            << "\n";
     ErrorStatus = true;
   }
 }
 
 } // end of namespace Ice