CodeGen: Refactor MIR parsing

[MatzeB]

Summary

When parsing .mir files immediately construct the MachineFunctions and
put them into MachineModuleInfo.

This allows us to get rid of the delayed construction (and delayed error
reporting) through the MachineFunctionInitialzier interface.

[qcolombet]

LGTM.
Nitpicks below

include/llvm/CodeGen/MachineModuleInfo.h

153

Rename to getOrCreateMachineFunction

157

Rename to getMachineFunction

lib/CodeGen/MIRParser/MIRParser.cpp

64

Could you add a comment for that variable too?

include/llvm/CodeGen/MIRParser/MIRParser.h

 // This file declares the functions that parse the MIR serialization format
 // files.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CODEGEN_MIRPARSER_MIRPARSER_H
 #define LLVM_CODEGEN_MIRPARSER_MIRPARSER_H
 
-#include "llvm/CodeGen/MachineFunctionInitializer.h"
 #include "llvm/IR/Module.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include <memory>
 
 namespace llvm {
 
 class StringRef;
 class MIRParserImpl;
+class MachineModuleInfo;
 class SMDiagnostic;
 
 /// This class initializes machine functions by applying the state loaded from
 /// a MIR file.
-class MIRParser : public MachineFunctionInitializer {
+class MIRParser {
   std::unique_ptr<MIRParserImpl> Impl;
 
 public:
   MIRParser(std::unique_ptr<MIRParserImpl> Impl);
   MIRParser(const MIRParser &) = delete;
-  ~MIRParser() override;
+  ~MIRParser();
 
-  /// Parse the optional LLVM IR module that's embedded in the MIR file.
+  /// Parses the optional LLVM IR module in the MIR file.
   ///
   /// A new, empty module is created if the LLVM IR isn't present.
-  /// Returns null if a parsing error occurred.
-  std::unique_ptr<Module> parseLLVMModule();
+  /// \returns nullptr if a parsing error occurred.
+  std::unique_ptr<Module> parseIRModule();
 
-  /// Initialize the machine function to the state that's described in the MIR
-  /// file.
+  /// \brief Parses MachineFunctions in the MIR file and add them to the given
+  /// MachineModuleInfo \p MMI.
   ///
-  /// Return true if error occurred.
-  bool initializeMachineFunction(MachineFunction &MF) override;
+  /// \returns true if an error occurred.
+  bool parseMachineFunctions(Module &M, MachineModuleInfo &MMI);
 };
 
 /// This function is the main interface to the MIR serialization format parser.
 ///
 /// It reads in a MIR file and returns a MIR parser that can parse the embedded
 /// LLVM IR module and initialize the machine functions by parsing the machine
 /// function's state.
 ///

include/llvm/CodeGen/MachineFunctionInitializer.h

-//=- MachineFunctionInitializer.h - machine function initializer --*- C++ -*-=//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file declares an interface that allows custom machine function
-// initialization.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_CODEGEN_MACHINEFUNCTIONINITIALIZER_H
-#define LLVM_CODEGEN_MACHINEFUNCTIONINITIALIZER_H
-
-namespace llvm {
-
-class MachineFunction;
-
-/// This interface provides a way to initialize machine functions after they are
-/// created by the machine function analysis pass.
-class MachineFunctionInitializer {
-  virtual void anchor();
-
-public:
-  virtual ~MachineFunctionInitializer() = default;
-
-  /// Initialize the machine function.
-  ///
-  /// Return true if error occurred.
-  virtual bool initializeMachineFunction(MachineFunction &MF) = 0;
-};
-
-} // end namespace llvm
-
-#endif // LLVM_CODEGEN_MACHINEFUNCTIONINITIALIZER_H

include/llvm/CodeGen/MachineModuleInfo.h

 #include <vector>
 
 namespace llvm {
 
 class BasicBlock;
 class CallInst;
 class Function;
 class MachineFunction;
-class MachineFunctionInitializer;
 class MMIAddrLabelMap;
 class Module;
 class TargetMachine;
 
 //===----------------------------------------------------------------------===//
 /// This class can be derived from and used by targets to hold private
 /// target-specific information for each Module.  Objects of type are
 /// accessed/created with MMI::getInfo and destroyed when the MachineModuleInfo
class MachineModuleInfo : public ImmutablePass {
   bool UsesVAFloatArgument;
 
   /// True if the module calls the __morestack function indirectly, as is
   /// required under the large code model on x86. This is used to emit
   /// a definition of a symbol, __morestack_addr, containing the address. See
   /// comments in lib/Target/X86/X86FrameLowering.cpp for more details.
   bool UsesMorestackAddr;
 
-  MachineFunctionInitializer *MFInitializer;
   /// Maps IR Functions to their corresponding MachineFunctions.
   DenseMap<const Function*, std::unique_ptr<MachineFunction>> MachineFunctions;
   /// Next unique number available for a MachineFunction.
   unsigned NextFnNum = 0;
   const Function *LastRequest = nullptr; ///< Used for shortcut/cache.
   MachineFunction *LastResult = nullptr; ///< Used for shortcut/cache.
 
 public:
   static char ID; // Pass identification, replacement for typeid
 
   explicit MachineModuleInfo(const TargetMachine *TM = nullptr);
   ~MachineModuleInfo() override;
 
   // Initialization and Finalization
   bool doInitialization(Module &) override;
   bool doFinalization(Module &) override;
 
   const MCContext &getContext() const { return Context; }
   MCContext &getContext() { return Context; }
 
   void setModule(const Module *M) { TheModule = M; }
   const Module *getModule() const { return TheModule; }
 
-  void setMachineFunctionInitializer(MachineFunctionInitializer *MFInit) {
-    MFInitializer = MFInit;
-  }
-
   /// Returns the MachineFunction constructed for the IR function \p F.
-  /// Creates a new MachineFunction and runs the MachineFunctionInitializer
-  /// if none exists yet.
+  /// Creates a new MachineFunction if none exists yet.
   MachineFunction &getMachineFunction(const Function &F);
 
+  /// \bried Returns the MachineFunction associated to IR function \p F if there
+  /// is one, otherwise nullptr.
+  MachineFunction *queryMachineFunction(const Function &F) const;
+
   /// Delete the MachineFunction \p MF and reset the link in the IR Function to
   /// Machine Function map.
   void deleteMachineFunctionFor(Function &F);
 
   /// Keep track of various per-function pieces of information for backends
   /// that would like to do so.
   template<typename Ty>
   Ty &getObjFileInfo() {

include/llvm/Target/TargetMachine.h

 #include "llvm/Pass.h"
 #include "llvm/Support/CodeGen.h"
 #include "llvm/Target/TargetOptions.h"
 #include <string>
 
 namespace llvm {
 
 class GlobalValue;
-class MachineFunctionInitializer;
 class Mangler;
 class MCAsmInfo;
 class MCContext;
 class MCInstrInfo;
 class MCRegisterInfo;
 class MCSubtargetInfo;
 class MCSymbol;
 class raw_pwrite_stream;
public:
   /// Add passes to the specified pass manager to get the specified file
   /// emitted.  Typically this will involve several steps of code generation.
   /// This method should return true if emission of this file type is not
   /// supported, or false on success.
   virtual bool addPassesToEmitFile(
       PassManagerBase &, raw_pwrite_stream &, CodeGenFileType,
       bool /*DisableVerify*/ = true, AnalysisID /*StartBefore*/ = nullptr,
       AnalysisID /*StartAfter*/ = nullptr, AnalysisID /*StopBefore*/ = nullptr,
-      AnalysisID /*StopAfter*/ = nullptr,
-      MachineFunctionInitializer * /*MFInitializer*/ = nullptr) {
+      AnalysisID /*StopAfter*/ = nullptr) {
     return true;
   }
 
   /// Add passes to the specified pass manager to get machine code emitted with
   /// the MCJIT. This method returns true if machine code is not supported. It
   /// fills the MCContext Ctx pointer which can be used to build custom
   /// MCStreamer.
   ///
public:
   virtual TargetPassConfig *createPassConfig(PassManagerBase &PM);
 
   /// Add passes to the specified pass manager to get the specified file
   /// emitted.  Typically this will involve several steps of code generation.
   bool addPassesToEmitFile(
       PassManagerBase &PM, raw_pwrite_stream &Out, CodeGenFileType FileType,
       bool DisableVerify = true, AnalysisID StartBefore = nullptr,
       AnalysisID StartAfter = nullptr, AnalysisID StopBefore = nullptr,
-      AnalysisID StopAfter = nullptr,
-      MachineFunctionInitializer *MFInitializer = nullptr) override;
+      AnalysisID StopAfter = nullptr) override;
 
   /// Add passes to the specified pass manager to get machine code emitted with
   /// the MCJIT. This method returns true if machine code is not supported. It
   /// fills the MCContext Ctx pointer which can be used to build custom
   /// MCStreamer.
   bool addPassesToEmitMC(PassManagerBase &PM, MCContext *&Ctx,
                          raw_pwrite_stream &OS,
                          bool DisableVerify = true) override;

lib/CodeGen/LLVMTargetMachine.cpp

TargetIRAnalysis LLVMTargetMachine::getTargetIRAnalysis() {
   });
 }
 
 /// addPassesToX helper drives creation and initialization of TargetPassConfig.
 static MCContext *
 addPassesToGenerateCode(LLVMTargetMachine *TM, PassManagerBase &PM,
                         bool DisableVerify, AnalysisID StartBefore,
                         AnalysisID StartAfter, AnalysisID StopBefore,
-                        AnalysisID StopAfter,
-                        MachineFunctionInitializer *MFInitializer = nullptr) {
-
+                        AnalysisID StopAfter) {
   // Targets may override createPassConfig to provide a target-specific
   // subclass.
   TargetPassConfig *PassConfig = TM->createPassConfig(PM);
   PassConfig->setStartStopPasses(StartBefore, StartAfter, StopBefore,
                                  StopAfter);
   // Set PassConfig options provided by TargetMachine.
   PassConfig->setDisableVerify(DisableVerify);
   PM.add(PassConfig);
addPassesToGenerateCode(LLVMTargetMachine *TM, PassManagerBase &PM,
 
   PassConfig->addCodeGenPrepare();
 
   PassConfig->addPassesToHandleExceptions();
 
   PassConfig->addISelPrepare();
 
   MachineModuleInfo *MMI = new MachineModuleInfo(TM);
-  MMI->setMachineFunctionInitializer(MFInitializer);
   PM.add(MMI);
 
   // Enable FastISel with -fast, but allow that to be overridden.
   TM->setO0WantsFastISel(EnableFastISelOption != cl::BOU_FALSE);
   if (EnableFastISelOption == cl::BOU_TRUE ||
       (TM->getOptLevel() == CodeGenOpt::None &&
        TM->getO0WantsFastISel()))
     TM->setFastISel(true);
addPassesToGenerateCode(LLVMTargetMachine *TM, PassManagerBase &PM,
   PassConfig->setInitialized();
 
   return &MMI->getContext();
 }
 
 bool LLVMTargetMachine::addPassesToEmitFile(
     PassManagerBase &PM, raw_pwrite_stream &Out, CodeGenFileType FileType,
     bool DisableVerify, AnalysisID StartBefore, AnalysisID StartAfter,
-    AnalysisID StopBefore, AnalysisID StopAfter,
-    MachineFunctionInitializer *MFInitializer) {
+    AnalysisID StopBefore, AnalysisID StopAfter) {
   // Add common CodeGen passes.
   MCContext *Context =
       addPassesToGenerateCode(this, PM, DisableVerify, StartBefore, StartAfter,
-                              StopBefore, StopAfter, MFInitializer);
+                              StopBefore, StopAfter);
   if (!Context)
     return true;
 
   if (StopBefore || StopAfter) {
     PM.add(createPrintMIRPass(Out));
     return false;
   }
 

lib/CodeGen/MIRParser/MIRParser.cpp

 using namespace llvm;
 
 namespace llvm {
 
 /// This class implements the parsing of LLVM IR that's embedded inside a MIR
 /// file.
 class MIRParserImpl {
   SourceMgr SM;
+  yaml::Input In;
   StringRef Filename;
   LLVMContext &Context;
-  StringMap<std::unique_ptr<yaml::MachineFunction>> Functions;
   SlotMapping IRSlots;
   /// Maps from register class names to register classes.
   Name2RegClassMap Names2RegClasses;
   /// Maps from register bank names to register banks.
   Name2RegBankMap Names2RegBanks;
+  /// True when the MIR file doesn't have LLVM IR. Dummy IR functions are
+  /// created and inserted into the given module when this is true.
+  bool NoLLVMIR = false;
+  bool NoMIRDocuments = false;
 
 public:
-  MIRParserImpl(std::unique_ptr<MemoryBuffer> Contents, StringRef Filename,
-                LLVMContext &Context);
+  MIRParserImpl(std::unique_ptr<MemoryBuffer> Contents,
+                StringRef Filename, LLVMContext &Context);
 
   void reportDiagnostic(const SMDiagnostic &Diag);
 
   /// Report an error with the given message at unknown location.
   ///
   /// Always returns true.
   bool error(const Twine &Message);
 
   /// Report an error with the given message at the given location.
   ///
   /// Always returns true.
   bool error(SMLoc Loc, const Twine &Message);
 
   /// Report a given error with the location translated from the location in an
   /// embedded string literal to a location in the MIR file.
   ///
   /// Always returns true.
   bool error(const SMDiagnostic &Error, SMRange SourceRange);
 
   /// Try to parse the optional LLVM module and the machine functions in the MIR
   /// file.
   ///
   /// Return null if an error occurred.
-  std::unique_ptr<Module> parse();
+  std::unique_ptr<Module> parseIRModule();
+
+  bool parseMachineFunctions(Module &M, MachineModuleInfo &MMI);
 
   /// Parse the machine function in the current YAML document.
   ///
-  /// \param NoLLVMIR - set to true when the MIR file doesn't have LLVM IR.
-  /// A dummy IR function is created and inserted into the given module when
-  /// this parameter is true.
   ///
   /// Return true if an error occurred.
-  bool parseMachineFunction(yaml::Input &In, Module &M, bool NoLLVMIR);
+  bool parseMachineFunction(Module &M, MachineModuleInfo &MMI);
 
   /// Initialize the machine function to the state that's described in the MIR
   /// file.
   ///
   /// Return true if error occurred.
-  bool initializeMachineFunction(MachineFunction &MF);
+  bool initializeMachineFunction(const yaml::MachineFunction &YamlMF,
+                                 MachineFunction &MF);
 
   bool parseRegisterInfo(PerFunctionMIParsingState &PFS,
                          const yaml::MachineFunction &YamlMF);
 
   bool setupRegisterInfo(const PerFunctionMIParsingState &PFS,
                          const yaml::MachineFunction &YamlMF);
 
   bool initializeFrameInfo(PerFunctionMIParsingState &PFS,
private:
   SMDiagnostic diagFromMIStringDiag(const SMDiagnostic &Error,
                                     SMRange SourceRange);
 
   /// Return a MIR diagnostic converted from a diagnostic located in a YAML
   /// block scalar string.
   SMDiagnostic diagFromBlockStringDiag(const SMDiagnostic &Error,
                                        SMRange SourceRange);
 
-  /// Create an empty function with the given name.
-  void createDummyFunction(StringRef Name, Module &M);
-
   void initNames2RegClasses(const MachineFunction &MF);
   void initNames2RegBanks(const MachineFunction &MF);
 
   /// Check if the given identifier is a name of a register class.
   ///
   /// Return null if the name isn't a register class.
   const TargetRegisterClass *getRegClass(const MachineFunction &MF,
                                          StringRef Name);
 
   /// Check if the given identifier is a name of a register bank.
   ///
   /// Return null if the name isn't a register bank.
   const RegisterBank *getRegBank(const MachineFunction &MF, StringRef Name);
 
   void computeFunctionProperties(MachineFunction &MF);
 };
 
 } // end namespace llvm
 
+static void handleYAMLDiag(const SMDiagnostic &Diag, void *Context) {
+  reinterpret_cast<MIRParserImpl *>(Context)->reportDiagnostic(Diag);
+}
+
 MIRParserImpl::MIRParserImpl(std::unique_ptr<MemoryBuffer> Contents,
                              StringRef Filename, LLVMContext &Context)
-    : SM(), Filename(Filename), Context(Context) {
-  SM.AddNewSourceBuffer(std::move(Contents), SMLoc());
+    : SM(),
+      In(SM.getMemoryBuffer(
+            SM.AddNewSourceBuffer(std::move(Contents), SMLoc()))->getBuffer(),
+            nullptr, handleYAMLDiag, this),
+      Filename(Filename),
+      Context(Context) {
+  In.setContext(&In);
 }
 
 bool MIRParserImpl::error(const Twine &Message) {
   Context.diagnose(DiagnosticInfoMIRParser(
       DS_Error, SMDiagnostic(Filename, SourceMgr::DK_Error, Message.str())));
   return true;
 }
 
case SourceMgr::DK_Warning:
     break;
   case SourceMgr::DK_Note:
     Kind = DS_Note;
     break;
   }
   Context.diagnose(DiagnosticInfoMIRParser(Kind, Diag));
 }
 
-static void handleYAMLDiag(const SMDiagnostic &Diag, void *Context) {
-  reinterpret_cast<MIRParserImpl *>(Context)->reportDiagnostic(Diag);
-}
-
-std::unique_ptr<Module> MIRParserImpl::parse() {
-  yaml::Input In(SM.getMemoryBuffer(SM.getMainFileID())->getBuffer(),
-                 /*Ctxt=*/nullptr, handleYAMLDiag, this);
-  In.setContext(&In);
-
+std::unique_ptr<Module> MIRParserImpl::parseIRModule() {
   if (!In.setCurrentDocument()) {
     if (In.error())
       return nullptr;
     // Create an empty module when the MIR file is empty.
+    NoMIRDocuments = true;
     return llvm::make_unique<Module>(Filename, Context);
   }
 
   std::unique_ptr<Module> M;
-  bool NoLLVMIR = false;
   // Parse the block scalar manually so that we can return unique pointer
   // without having to go trough YAML traits.
   if (const auto *BSN =
           dyn_cast_or_null<yaml::BlockScalarNode>(In.getCurrentNode())) {
     SMDiagnostic Error;
     M = parseAssembly(MemoryBufferRef(BSN->getValue(), Filename), Error,
                       Context, &IRSlots);
     if (!M) {
       reportDiagnostic(diagFromBlockStringDiag(Error, BSN->getSourceRange()));
       return nullptr;
     }
     In.nextDocument();
     if (!In.setCurrentDocument())
-      return M;
+      NoMIRDocuments = true;
   } else {
     // Create an new, empty module.
     M = llvm::make_unique<Module>(Filename, Context);
     NoLLVMIR = true;
   }
+  return M;
+}
+
+bool MIRParserImpl::parseMachineFunctions(Module &M, MachineModuleInfo &MMI) {
+  if (NoMIRDocuments)
+    return false;
 
   // Parse the machine functions.
   do {
-    if (parseMachineFunction(In, *M, NoLLVMIR))
-      return nullptr;
+    if (parseMachineFunction(M, MMI))
+      return true;
     In.nextDocument();
   } while (In.setCurrentDocument());
 
-  return M;
+  return false;
 }
 
-bool MIRParserImpl::parseMachineFunction(yaml::Input &In, Module &M,
-                                         bool NoLLVMIR) {
-  auto MF = llvm::make_unique<yaml::MachineFunction>();
+/// Create an empty function with the given name.
+static Function *createDummyFunction(StringRef Name, Module &M) {
+  auto &Context = M.getContext();
+  Function *F = cast<Function>(M.getOrInsertFunction(
+      Name, FunctionType::get(Type::getVoidTy(Context), false)));
+  BasicBlock *BB = BasicBlock::Create(Context, "entry", F);
+  new UnreachableInst(Context, BB);
+  return F;
+}
+
+bool MIRParserImpl::parseMachineFunction(Module &M, MachineModuleInfo &MMI) {
+  // Parse the yaml.
+  yaml::MachineFunction YamlMF;
   yaml::EmptyContext Ctx;
-  yaml::yamlize(In, *MF, false, Ctx);
+  yaml::yamlize(In, YamlMF, false, Ctx);
   if (In.error())
     return true;
-  auto FunctionName = MF->Name;
-  if (Functions.find(FunctionName) != Functions.end())
-    return error(Twine("redefinition of machine function '") + FunctionName +
-                 "'");
-  Functions.insert(std::make_pair(FunctionName, std::move(MF)));
-  if (NoLLVMIR)
-    createDummyFunction(FunctionName, M);
-  else if (!M.getFunction(FunctionName))
+
+  // Search for the corresponding IR function.
+  StringRef FunctionName = YamlMF.Name;
+  Function *F = M.getFunction(FunctionName);
+  if (!F) {
+    if (NoLLVMIR) {
+      F = createDummyFunction(FunctionName, M);
+    } else {
       return error(Twine("function '") + FunctionName +
                    "' isn't defined in the provided LLVM IR");
-  return false;
     }
+  }
+  if (MMI.queryMachineFunction(*F) != nullptr)
+    return error(Twine("redefinition of machine function '") + FunctionName +
+                 "'");
 
-void MIRParserImpl::createDummyFunction(StringRef Name, Module &M) {
-  auto &Context = M.getContext();
-  Function *F = cast<Function>(M.getOrInsertFunction(
-      Name, FunctionType::get(Type::getVoidTy(Context), false)));
-  BasicBlock *BB = BasicBlock::Create(Context, "entry", F);
-  new UnreachableInst(Context, BB);
+  // Create the MachineFunction.
+  MachineFunction &MF = MMI.getMachineFunction(*F);
+  if (initializeMachineFunction(YamlMF, MF))
+    return true;
+
+  return false;
 }
 
 static bool isSSA(const MachineFunction &MF) {
   const MachineRegisterInfo &MRI = MF.getRegInfo();
   for (unsigned I = 0, E = MRI.getNumVirtRegs(); I != E; ++I) {
     unsigned Reg = TargetRegisterInfo::index2VirtReg(I);
     if (!MRI.hasOneDef(Reg) && !MRI.def_empty(Reg))
       return false;
void MIRParserImpl::computeFunctionProperties(MachineFunction &MF) {
   else
     Properties.reset(MachineFunctionProperties::Property::IsSSA);
 
   const MachineRegisterInfo &MRI = MF.getRegInfo();
   if (MRI.getNumVirtRegs() == 0)
     Properties.set(MachineFunctionProperties::Property::NoVRegs);
 }
 
-bool MIRParserImpl::initializeMachineFunction(MachineFunction &MF) {
-  auto It = Functions.find(MF.getName());
-  if (It == Functions.end())
-    return error(Twine("no machine function information for function '") +
-                 MF.getName() + "' in the MIR file");
+bool
+MIRParserImpl::initializeMachineFunction(const yaml::MachineFunction &YamlMF,
+                                         MachineFunction &MF) {
   // TODO: Recreate the machine function.
   initNames2RegClasses(MF);
   initNames2RegBanks(MF);
-  const yaml::MachineFunction &YamlMF = *It->getValue();
   if (YamlMF.Alignment)
     MF.setAlignment(YamlMF.Alignment);
   MF.setExposesReturnsTwice(YamlMF.ExposesReturnsTwice);
 
   if (YamlMF.Legalized)
     MF.getProperties().set(MachineFunctionProperties::Property::Legalized);
   if (YamlMF.RegBankSelected)
     MF.getProperties().set(
const RegisterBank *MIRParserImpl::getRegBank(const MachineFunction &MF,
   return RegBankInfo->getValue();
 }
 
 MIRParser::MIRParser(std::unique_ptr<MIRParserImpl> Impl)
     : Impl(std::move(Impl)) {}
 
 MIRParser::~MIRParser() {}
 
-std::unique_ptr<Module> MIRParser::parseLLVMModule() { return Impl->parse(); }
+std::unique_ptr<Module> MIRParser::parseIRModule() {
+  return Impl->parseIRModule();
+}
 
-bool MIRParser::initializeMachineFunction(MachineFunction &MF) {
-  return Impl->initializeMachineFunction(MF);
+bool MIRParser::parseMachineFunctions(Module &M, MachineModuleInfo &MMI) {
+  return Impl->parseMachineFunctions(M, MMI);
 }
 
 std::unique_ptr<MIRParser> llvm::createMIRParserFromFile(StringRef Filename,
                                                          SMDiagnostic &Error,
                                                          LLVMContext &Context) {
   auto FileOrErr = MemoryBuffer::getFile(Filename);
   if (std::error_code EC = FileOrErr.getError()) {
     Error = SMDiagnostic(Filename, SourceMgr::DK_Error,

lib/CodeGen/MachineFunction.cpp

 
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/Analysis/ConstantFolding.h"
 #include "llvm/Analysis/EHPersonalities.h"
 #include "llvm/CodeGen/MachineConstantPool.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
-#include "llvm/CodeGen/MachineFunctionInitializer.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachineInstr.h"
 #include "llvm/CodeGen/MachineJumpTableInfo.h"
 #include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/Passes.h"
 #include "llvm/CodeGen/PseudoSourceValue.h"
 #include "llvm/CodeGen/WinEHFuncInfo.h"

 
 #define DEBUG_TYPE "codegen"
 
 static cl::opt<unsigned>
     AlignAllFunctions("align-all-functions",
                       cl::desc("Force the alignment of all functions."),
                       cl::init(0), cl::Hidden);
 
-void MachineFunctionInitializer::anchor() {}
-
 static const char *getPropertyName(MachineFunctionProperties::Property Prop) {
   typedef MachineFunctionProperties::Property P;
   switch(Prop) {
   case P::FailedISel: return "FailedISel";
   case P::IsSSA: return "IsSSA";
   case P::Legalized: return "Legalized";
   case P::NoPHIs: return "NoPHIs";
   case P::NoVRegs: return "NoVRegs";

lib/CodeGen/MachineModuleInfo.cpp

 //===-- llvm/CodeGen/MachineModuleInfo.cpp ----------------------*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/PostOrderIterator.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/TinyPtrVector.h"
 #include "llvm/CodeGen/MachineFunction.h"
-#include "llvm/CodeGen/MachineFunctionInitializer.h"
 #include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/CodeGen/Passes.h"
 #include "llvm/IR/BasicBlock.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/Value.h"
 #include "llvm/IR/ValueHandle.h"
void MachineModuleInfo::addPersonality(const Function *Personality) {
   for (unsigned i = 0; i < Personalities.size(); ++i)
     if (Personalities[i] == Personality)
       return;
   Personalities.push_back(Personality);
 }
 
 /// \}
 
+MachineFunction *
+MachineModuleInfo::queryMachineFunction(const Function &F) const {
+  auto I = MachineFunctions.find(&F);
+  return I != MachineFunctions.end() ? I->second.get() : nullptr;
+}
+
 MachineFunction &MachineModuleInfo::getMachineFunction(const Function &F) {
   // Shortcut for the common case where a sequence of MachineFunctionPasses
   // all query for the same Function.
   if (LastRequest == &F)
     return *LastResult;
 
   auto I = MachineFunctions.insert(
       std::make_pair(&F, std::unique_ptr<MachineFunction>()));
   MachineFunction *MF;
   if (I.second) {
     // No pre-existing machine function, create a new one.
     MF = new MachineFunction(&F, TM, NextFnNum++, *this);
     // Update the set entry.
     I.first->second.reset(MF);
-
-    if (MFInitializer)
-      if (MFInitializer->initializeMachineFunction(*MF))
-        report_fatal_error("Unable to initialize machine function");
   } else {
     MF = I.first->second.get();
   }
 
   LastRequest = &F;
   LastResult = MF;
   return *MF;
 }

test/CodeGen/MIR/AArch64/generic-virtual-registers-error.mir

 name:            baz
 registers:
   - { id: 0, class: _ }
 body: |
   bb.0:
     liveins: %w0
     ; ERR: generic virtual registers must have a type
     ; ERR-NEXT: %0
-    ; ERR: Unable to initialize machine function
     %0 = G_ADD i32 %w0, %w0
 ...

test/CodeGen/MIR/AArch64/generic-virtual-registers-with-regbank-error.mir

 name:            bar
 registers:
   - { id: 0, class: gpr }
 body: |
   bb.0:
     liveins: %w0
     ; ERR: generic virtual registers must have a type
     ; ERR-NEXT: %0
-    ; ERR: Unable to initialize machine function
     %0 = G_ADD i32 %w0, %w0
 ...

test/CodeGen/MIR/Generic/function-missing-machine-function.mir

-# RUN: not llc -run-pass none -o /dev/null %s 2>&1 | FileCheck %s
-# This test verifies that an error is reported when a MIR file has some
-# function but is missing a corresponding machine function.
-
-# CHECK: no machine function information for function 'foo' in the MIR file
-
---- |
-
-  define i32 @foo() {
-    ret i32 0
-  }
-
-...

test/CodeGen/MIR/X86/empty0.mir

+# RUN: llc -run-pass none -o - %s | FileCheck %s
+# Make sure empty files don't crash us
+# CHECK: --- |
+# ... moduleid, sourcefilename stuff here ..
+# CHECK: target datalayout =
+# CHECK: ...

test/CodeGen/MIR/X86/empty1.mir

+# RUN: llc -run-pass none -o - %s | FileCheck %s
+# Make sure empty files don't crash us
+--- |
+...
+# CHECK: --- |
+# ... moduleid, sourcefilename stuff here ..
+# CHECK: target datalayout =
+# CHECK: ...

test/CodeGen/MIR/X86/empty2.mir

+# RUN: llc -run-pass none -o - %s | FileCheck %s
+# Make sure empty files don't crash us
+---
+...
+# CHECK: --- |
+# ... moduleid, sourcefilename stuff here ..
+# CHECK: target datalayout =
+# CHECK: ...

tools/llc/llc.cpp

static int compileModule(char **argv, LLVMContext &Context) {
   bool SkipModule = MCPU == "help" ||
                     (!MAttrs.empty() && MAttrs.front() == "help");
 
   // If user just wants to list available options, skip module loading
   if (!SkipModule) {
     if (StringRef(InputFilename).endswith_lower(".mir")) {
       MIR = createMIRParserFromFile(InputFilename, Err, Context);
       if (MIR)
-        M = MIR->parseLLVMModule();
+        M = MIR->parseIRModule();
     } else
       M = parseIRFile(InputFilename, Err, Context);
     if (!M) {
       Err.print(argv[0], errs());
       return 1;
     }
 
     // Verify module immediately to catch problems before doInitialization() is
if (!RunPassNames->empty()) {
       if (!MIR) {
         errs() << argv[0] << ": run-pass needs a .mir input.\n";
         return 1;
       }
       LLVMTargetMachine &LLVMTM = static_cast<LLVMTargetMachine&>(*Target);
       TargetPassConfig &TPC = *LLVMTM.createPassConfig(PM);
       PM.add(&TPC);
       MachineModuleInfo *MMI = new MachineModuleInfo(&LLVMTM);
-      MMI->setMachineFunctionInitializer(MIR.get());
+      if (MIR->parseMachineFunctions(*M, *MMI))
+        return 1;
       PM.add(MMI);
       TPC.printAndVerify("");
 
       for (const std::string &RunPassName : *RunPassNames) {
         if (addPass(PM, argv[0], RunPassName, TPC))
           return 1;
       }
       PM.add(createPrintMIRPass(*OS));
if (!RunPassNames->empty()) {
       if (StopBeforeID && StopAfterID) {
         errs() << argv[0] << ": -stop-before and -stop-after specified!\n";
         return 1;
       }
 
       // Ask the target to add backend passes as necessary.
       if (Target->addPassesToEmitFile(PM, *OS, FileType, NoVerify,
                                       StartBeforeID, StartAfterID, StopBeforeID,
-                                      StopAfterID, MIR.get())) {
+                                      StopAfterID)) {
         errs() << argv[0] << ": target does not support generation of this"
                << " file type!\n";
         return 1;
       }
     }
 
     // Before executing passes, print the final values of the LLVM options.
     cl::PrintOptionValues();