Implement LTOModule on top of IRObjectFile.

IRObjectFile provides all the logic for producing mangled names and getting
symbols from inline assembly.

LTOModule then adds logic for linking specific tasks, like constructing
llvm.compiler_user or extracting linker options from the bitcode.

The rule of the thumb is that IRObjectFile has the functionality that is
needed by both LTO and llvm-ar.

llvm-svn: 212349

2 files changed, 76 insertions, 127 deletions

diff --git a/llvm/lib/LTO/LTOCodeGenerator.cpp b/llvm/lib/LTO/LTOCodeGenerator.cpp
index a1709f60fff..4b51166a755 100644
--- a/llvm/lib/LTO/LTOCodeGenerator.cpp
+++ b/llvm/lib/LTO/LTOCodeGenerator.cpp
@@ -114,7 +114,7 @@ void LTOCodeGenerator::initializeLTOPasses() {
 }
 
 bool LTOCodeGenerator::addModule(LTOModule* mod, std::string& errMsg) {
-  bool ret = IRLinker.linkInModule(mod->getLLVVMModule(), &errMsg);
+  bool ret = IRLinker.linkInModule(&mod->getModule(), &errMsg);
 
   const std::vector<const char*> &undefs = mod->getAsmUndefinedRefs();
   for (int i = 0, e = undefs.size(); i != e; ++i)
diff --git a/llvm/lib/LTO/LTOModule.cpp b/llvm/lib/LTO/LTOModule.cpp
index 45e3a21df72..314831ff6f8 100644
--- a/llvm/lib/LTO/LTOModule.cpp
+++ b/llvm/lib/LTO/LTOModule.cpp
@@ -28,7 +28,6 @@
 #include "llvm/MC/MCSymbol.h"
 #include "llvm/MC/MCTargetAsmParser.h"
 #include "llvm/MC/SubtargetFeature.h"
-#include "llvm/Object/RecordStreamer.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Host.h"
@@ -44,15 +43,9 @@
 #include <system_error>
 using namespace llvm;
 
-LTOModule::LTOModule(std::unique_ptr<Module> M, TargetMachine *TM)
-    : _module(std::move(M)), _target(TM),
-      _context(_target->getMCAsmInfo(), _target->getRegisterInfo(),
-               &ObjFileInfo),
-      _mangler(TM->getDataLayout()) {
-  ObjFileInfo.InitMCObjectFileInfo(TM->getTargetTriple(),
-                                   TM->getRelocationModel(), TM->getCodeModel(),
-                                   _context);
-}
+LTOModule::LTOModule(std::unique_ptr<object::IRObjectFile> Obj,
+                     llvm::TargetMachine *TM)
+    : IRFile(std::move(Obj)), _target(TM) {}
 
 /// isBitcodeFile - Returns 'true' if the file (or memory contents) is LLVM
 /// bitcode.
@@ -115,17 +108,15 @@ LTOModule *LTOModule::createFromBuffer(const void *mem, size_t length,
 LTOModule *LTOModule::makeLTOModule(std::unique_ptr<MemoryBuffer> Buffer,
                                     TargetOptions options,
                                     std::string &errMsg) {
-  // parse bitcode buffer
-  ErrorOr<Module *> ModuleOrErr =
+  ErrorOr<Module *> MOrErr =
       getLazyBitcodeModule(Buffer.get(), getGlobalContext());
-  if (std::error_code EC = ModuleOrErr.getError()) {
+  if (std::error_code EC = MOrErr.getError()) {
     errMsg = EC.message();
     return nullptr;
   }
-  Buffer.release();
-  std::unique_ptr<Module> m(ModuleOrErr.get());
+  std::unique_ptr<Module> M(MOrErr.get());
 
-  std::string TripleStr = m->getTargetTriple();
+  std::string TripleStr = M->getTargetTriple();
   if (TripleStr.empty())
     TripleStr = sys::getDefaultTargetTriple();
   llvm::Triple Triple(TripleStr);
@@ -153,18 +144,13 @@ LTOModule *LTOModule::makeLTOModule(std::unique_ptr<MemoryBuffer> Buffer,
 
   TargetMachine *target = march->createTargetMachine(TripleStr, CPU, FeatureStr,
                                                      options);
-  m->materializeAllPermanently();
+  M->materializeAllPermanently(true);
+  M->setDataLayout(target->getDataLayout());
 
-  LTOModule *Ret = new LTOModule(std::move(m), target);
+  std::unique_ptr<object::IRObjectFile> IRObj(
+      new object::IRObjectFile(std::move(Buffer), std::move(M)));
 
-  // We need a MCContext set up in order to get mangled names of private
-  // symbols. It is a bit odd that we need to report uses and definitions
-  // of private symbols, but it does look like ld64 expects to be informed
-  // of at least the ones with an 'l' prefix.
-  MCContext &Context = Ret->_context;
-  const TargetLoweringObjectFile &TLOF =
-      target->getTargetLowering()->getObjFileLowering();
-  const_cast<TargetLoweringObjectFile &>(TLOF).Initialize(Context, *target);
+  LTOModule *Ret = new LTOModule(std::move(IRObj), target);
 
   if (Ret->parseSymbols(errMsg)) {
     delete Ret;
@@ -283,9 +269,14 @@ void LTOModule::addObjCClassRef(const GlobalVariable *clgv) {
   entry.setValue(info);
 }
 
-void LTOModule::addDefinedDataSymbol(const GlobalValue *V) {
+void LTOModule::addDefinedDataSymbol(const object::BasicSymbolRef &Sym) {
   SmallString<64> Buffer;
-  _target->getNameWithPrefix(Buffer, V, _mangler);
+  {
+    raw_svector_ostream OS(Buffer);
+    Sym.printName(OS);
+  }
+
+  const GlobalValue *V = IRFile->getSymbolGV(Sym.getRawDataRefImpl());
   addDefinedDataSymbol(Buffer.c_str(), V);
 }
 
@@ -339,9 +330,15 @@ void LTOModule::addDefinedDataSymbol(const char *Name, const GlobalValue *v) {
   }
 }
 
-void LTOModule::addDefinedFunctionSymbol(const Function *F) {
+void LTOModule::addDefinedFunctionSymbol(const object::BasicSymbolRef &Sym) {
   SmallString<64> Buffer;
-  _target->getNameWithPrefix(Buffer, F, _mangler);
+  {
+    raw_svector_ostream OS(Buffer);
+    Sym.printName(OS);
+  }
+
+  const Function *F =
+      cast<Function>(IRFile->getSymbolGV(Sym.getRawDataRefImpl()));
   addDefinedFunctionSymbol(Buffer.c_str(), F);
 }
 
@@ -376,10 +373,6 @@ static bool canBeHidden(const GlobalValue *GV) {
 
 void LTOModule::addDefinedSymbol(const char *Name, const GlobalValue *def,
                                  bool isFunction) {
-  // ignore all llvm.* symbols
-  if (def->getName().startswith("llvm."))
-    return;
-
   // set alignment part log2() can have rounding errors
   uint32_t align = def->getAlignment();
   uint32_t attr = align ? countTrailingZeros(align) : 0;
@@ -499,20 +492,14 @@ void LTOModule::addAsmGlobalSymbolUndef(const char *name) {
   entry.setValue(info);
 }
 
-/// addPotentialUndefinedSymbol - Add a symbol which isn't defined just yet to a
-/// list to be resolved later.
-void
-LTOModule::addPotentialUndefinedSymbol(const GlobalValue *decl, bool isFunc) {
-  // ignore all llvm.* symbols
-  if (decl->getName().startswith("llvm."))
-    return;
-
-  // ignore all aliases
-  if (isa<GlobalAlias>(decl))
-    return;
-
+/// Add a symbol which isn't defined just yet to a list to be resolved later.
+void LTOModule::addPotentialUndefinedSymbol(const object::BasicSymbolRef &Sym,
+                                            bool isFunc) {
   SmallString<64> name;
-  _target->getNameWithPrefix(name, decl, _mangler);
+  {
+    raw_svector_ostream OS(name);
+    Sym.printName(OS);
+  }
 
   StringMap<NameAndAttributes>::value_type &entry =
     _undefines.GetOrCreateValue(name);
@@ -525,6 +512,8 @@ LTOModule::addPotentialUndefinedSymbol(const GlobalValue *decl, bool isFunc) {
 
   info.name = entry.getKey().data();
 
+  const GlobalValue *decl = IRFile->getSymbolGV(Sym.getRawDataRefImpl());
+
   if (decl->hasExternalWeakLinkage())
     info.attributes = LTO_SYMBOL_DEFINITION_WEAKUNDEF;
   else
@@ -536,90 +525,50 @@ LTOModule::addPotentialUndefinedSymbol(const GlobalValue *decl, bool isFunc) {
   entry.setValue(info);
 }
 
-/// addAsmGlobalSymbols - Add global symbols from module-level ASM to the
-/// defined or undefined lists.
-bool LTOModule::addAsmGlobalSymbols(std::string &errMsg) {
-  const std::string &inlineAsm = _module->getModuleInlineAsm();
-  if (inlineAsm.empty())
-    return false;
-
-  std::unique_ptr<RecordStreamer> Streamer(new RecordStreamer(_context));
-  MemoryBuffer *Buffer = MemoryBuffer::getMemBuffer(inlineAsm);
-  SourceMgr SrcMgr;
-  SrcMgr.AddNewSourceBuffer(Buffer, SMLoc());
-  std::unique_ptr<MCAsmParser> Parser(
-      createMCAsmParser(SrcMgr, _context, *Streamer, *_target->getMCAsmInfo()));
-  const Target &T = _target->getTarget();
-  std::unique_ptr<MCInstrInfo> MCII(T.createMCInstrInfo());
-  std::unique_ptr<MCSubtargetInfo> STI(T.createMCSubtargetInfo(
-      _target->getTargetTriple(), _target->getTargetCPU(),
-      _target->getTargetFeatureString()));
-  std::unique_ptr<MCTargetAsmParser> TAP(
-      T.createMCAsmParser(*STI, *Parser.get(), *MCII,
-                          _target->Options.MCOptions));
-  if (!TAP) {
-    errMsg = "target " + std::string(T.getName()) +
-      " does not define AsmParser.";
-    return true;
-  }
-
-  Parser->setTargetParser(*TAP);
-  if (Parser->Run(false))
-    return true;
-
-  for (auto &KV : *Streamer) {
-    StringRef Key = KV.first();
-    RecordStreamer::State Value = KV.second;
-    if (Value == RecordStreamer::DefinedGlobal)
-      addAsmGlobalSymbol(Key.data(), LTO_SYMBOL_SCOPE_DEFAULT);
-    else if (Value == RecordStreamer::Defined)
-      addAsmGlobalSymbol(Key.data(), LTO_SYMBOL_SCOPE_INTERNAL);
-    else if (Value == RecordStreamer::Global ||
-             Value == RecordStreamer::Used)
-      addAsmGlobalSymbolUndef(Key.data());
-  }
-
-  return false;
-}
-
-/// isDeclaration - Return 'true' if the global value is a declaration.
-static bool isDeclaration(const GlobalValue &V) {
-  if (V.hasAvailableExternallyLinkage())
-    return true;
-
-  if (V.isMaterializable())
-    return false;
-
-  return V.isDeclaration();
-}
-
 /// parseSymbols - Parse the symbols from the module and model-level ASM and add
 /// them to either the defined or undefined lists.
 bool LTOModule::parseSymbols(std::string &errMsg) {
-  // add functions
-  for (Module::iterator f = _module->begin(), e = _module->end(); f != e; ++f) {
-    if (isDeclaration(*f))
-      addPotentialUndefinedSymbol(f, true);
-    else
-      addDefinedFunctionSymbol(f);
-  }
+  for (auto &Sym : IRFile->symbols()) {
+    const GlobalValue *GV = IRFile->getSymbolGV(Sym.getRawDataRefImpl());
+    uint32_t Flags = Sym.getFlags();
+    bool IsUndefined = Flags & object::BasicSymbolRef::SF_Undefined;
+
+    if (!GV) {
+      SmallString<64> Buffer;
+      {
+        raw_svector_ostream OS(Buffer);
+        Sym.printName(OS);
+      }
+      const char *Name = Buffer.c_str();
+
+      if (IsUndefined)
+        addAsmGlobalSymbolUndef(Name);
+      else if (Flags & object::BasicSymbolRef::SF_Global)
+        addAsmGlobalSymbol(Name, LTO_SYMBOL_SCOPE_DEFAULT);
+      else
+        addAsmGlobalSymbol(Name, LTO_SYMBOL_SCOPE_INTERNAL);
+      continue;
+    }
 
-  // add data
-  for (Module::global_iterator v = _module->global_begin(),
-         e = _module->global_end(); v !=  e; ++v) {
-    if (isDeclaration(*v))
-      addPotentialUndefinedSymbol(v, false);
-    else
-      addDefinedDataSymbol(v);
-  }
+    auto *F = dyn_cast<Function>(GV);
+    if (IsUndefined) {
+      addPotentialUndefinedSymbol(Sym, F != nullptr);
+      continue;
+    }
 
-  // add asm globals
-  if (addAsmGlobalSymbols(errMsg))
-    return true;
+    if (F) {
+      addDefinedFunctionSymbol(Sym);
+      continue;
+    }
 
-  // add aliases
-  for (const auto &Alias : _module->aliases())
-    addDefinedDataSymbol(&Alias);
+    if (isa<GlobalVariable>(GV)) {
+      addDefinedDataSymbol(Sym);
+      continue;
+    }
+
+    assert(isa<GlobalAlias>(GV));
+    addDefinedDataSymbol(Sym);
+  }
 
   // make symbols for all undefines
   for (StringMap<NameAndAttributes>::iterator u =_undefines.begin(),
@@ -637,7 +586,7 @@ bool LTOModule::parseSymbols(std::string &errMsg) {
 /// parseMetadata - Parse metadata from the module
 void LTOModule::parseMetadata() {
   // Linker Options
-  if (Value *Val = _module->getModuleFlag("Linker Options")) {
+  if (Value *Val = getModule().getModuleFlag("Linker Options")) {
     MDNode *LinkerOptions = cast<MDNode>(Val);
     for (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) {
       MDNode *MDOptions = cast<MDNode>(LinkerOptions->getOperand(i));