652 lines
21 KiB
C++
652 lines
21 KiB
C++
//===-- LTOModule.cpp - LLVM Link Time Optimizer --------------------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file implements the Link Time Optimization library. This library is
|
|
// intended to be used by linker to optimize code at link time.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/LTO/legacy/LTOModule.h"
|
|
#include "llvm/ADT/Triple.h"
|
|
#include "llvm/Bitcode/BitcodeReader.h"
|
|
#include "llvm/CodeGen/TargetSubtargetInfo.h"
|
|
#include "llvm/IR/Constants.h"
|
|
#include "llvm/IR/LLVMContext.h"
|
|
#include "llvm/IR/Mangler.h"
|
|
#include "llvm/IR/Metadata.h"
|
|
#include "llvm/IR/Module.h"
|
|
#include "llvm/MC/MCExpr.h"
|
|
#include "llvm/MC/MCInst.h"
|
|
#include "llvm/MC/MCParser/MCAsmParser.h"
|
|
#include "llvm/MC/MCSection.h"
|
|
#include "llvm/MC/MCSubtargetInfo.h"
|
|
#include "llvm/MC/MCSymbol.h"
|
|
#include "llvm/MC/SubtargetFeature.h"
|
|
#include "llvm/Object/IRObjectFile.h"
|
|
#include "llvm/Object/ObjectFile.h"
|
|
#include "llvm/Support/FileSystem.h"
|
|
#include "llvm/Support/Host.h"
|
|
#include "llvm/Support/MemoryBuffer.h"
|
|
#include "llvm/Support/Path.h"
|
|
#include "llvm/Support/SourceMgr.h"
|
|
#include "llvm/Support/TargetRegistry.h"
|
|
#include "llvm/Support/TargetSelect.h"
|
|
#include "llvm/Target/TargetLoweringObjectFile.h"
|
|
#include "llvm/Transforms/Utils/GlobalStatus.h"
|
|
#include <system_error>
|
|
using namespace llvm;
|
|
using namespace llvm::object;
|
|
|
|
LTOModule::LTOModule(std::unique_ptr<Module> M, MemoryBufferRef MBRef,
|
|
llvm::TargetMachine *TM)
|
|
: Mod(std::move(M)), MBRef(MBRef), _target(TM) {
|
|
SymTab.addModule(Mod.get());
|
|
}
|
|
|
|
LTOModule::~LTOModule() {}
|
|
|
|
/// isBitcodeFile - Returns 'true' if the file (or memory contents) is LLVM
|
|
/// bitcode.
|
|
bool LTOModule::isBitcodeFile(const void *Mem, size_t Length) {
|
|
Expected<MemoryBufferRef> BCData = IRObjectFile::findBitcodeInMemBuffer(
|
|
MemoryBufferRef(StringRef((const char *)Mem, Length), "<mem>"));
|
|
return !errorToBool(BCData.takeError());
|
|
}
|
|
|
|
bool LTOModule::isBitcodeFile(StringRef Path) {
|
|
ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
|
|
MemoryBuffer::getFile(Path);
|
|
if (!BufferOrErr)
|
|
return false;
|
|
|
|
Expected<MemoryBufferRef> BCData = IRObjectFile::findBitcodeInMemBuffer(
|
|
BufferOrErr.get()->getMemBufferRef());
|
|
return !errorToBool(BCData.takeError());
|
|
}
|
|
|
|
bool LTOModule::isThinLTO() {
|
|
Expected<BitcodeLTOInfo> Result = getBitcodeLTOInfo(MBRef);
|
|
if (!Result) {
|
|
logAllUnhandledErrors(Result.takeError(), errs());
|
|
return false;
|
|
}
|
|
return Result->IsThinLTO;
|
|
}
|
|
|
|
bool LTOModule::isBitcodeForTarget(MemoryBuffer *Buffer,
|
|
StringRef TriplePrefix) {
|
|
Expected<MemoryBufferRef> BCOrErr =
|
|
IRObjectFile::findBitcodeInMemBuffer(Buffer->getMemBufferRef());
|
|
if (errorToBool(BCOrErr.takeError()))
|
|
return false;
|
|
LLVMContext Context;
|
|
ErrorOr<std::string> TripleOrErr =
|
|
expectedToErrorOrAndEmitErrors(Context, getBitcodeTargetTriple(*BCOrErr));
|
|
if (!TripleOrErr)
|
|
return false;
|
|
return StringRef(*TripleOrErr).startswith(TriplePrefix);
|
|
}
|
|
|
|
std::string LTOModule::getProducerString(MemoryBuffer *Buffer) {
|
|
Expected<MemoryBufferRef> BCOrErr =
|
|
IRObjectFile::findBitcodeInMemBuffer(Buffer->getMemBufferRef());
|
|
if (errorToBool(BCOrErr.takeError()))
|
|
return "";
|
|
LLVMContext Context;
|
|
ErrorOr<std::string> ProducerOrErr = expectedToErrorOrAndEmitErrors(
|
|
Context, getBitcodeProducerString(*BCOrErr));
|
|
if (!ProducerOrErr)
|
|
return "";
|
|
return *ProducerOrErr;
|
|
}
|
|
|
|
ErrorOr<std::unique_ptr<LTOModule>>
|
|
LTOModule::createFromFile(LLVMContext &Context, StringRef path,
|
|
const TargetOptions &options) {
|
|
ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
|
|
MemoryBuffer::getFile(path);
|
|
if (std::error_code EC = BufferOrErr.getError()) {
|
|
Context.emitError(EC.message());
|
|
return EC;
|
|
}
|
|
std::unique_ptr<MemoryBuffer> Buffer = std::move(BufferOrErr.get());
|
|
return makeLTOModule(Buffer->getMemBufferRef(), options, Context,
|
|
/* ShouldBeLazy*/ false);
|
|
}
|
|
|
|
ErrorOr<std::unique_ptr<LTOModule>>
|
|
LTOModule::createFromOpenFile(LLVMContext &Context, int fd, StringRef path,
|
|
size_t size, const TargetOptions &options) {
|
|
return createFromOpenFileSlice(Context, fd, path, size, 0, options);
|
|
}
|
|
|
|
ErrorOr<std::unique_ptr<LTOModule>>
|
|
LTOModule::createFromOpenFileSlice(LLVMContext &Context, int fd, StringRef path,
|
|
size_t map_size, off_t offset,
|
|
const TargetOptions &options) {
|
|
ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
|
|
MemoryBuffer::getOpenFileSlice(fd, path, map_size, offset);
|
|
if (std::error_code EC = BufferOrErr.getError()) {
|
|
Context.emitError(EC.message());
|
|
return EC;
|
|
}
|
|
std::unique_ptr<MemoryBuffer> Buffer = std::move(BufferOrErr.get());
|
|
return makeLTOModule(Buffer->getMemBufferRef(), options, Context,
|
|
/* ShouldBeLazy */ false);
|
|
}
|
|
|
|
ErrorOr<std::unique_ptr<LTOModule>>
|
|
LTOModule::createFromBuffer(LLVMContext &Context, const void *mem,
|
|
size_t length, const TargetOptions &options,
|
|
StringRef path) {
|
|
StringRef Data((const char *)mem, length);
|
|
MemoryBufferRef Buffer(Data, path);
|
|
return makeLTOModule(Buffer, options, Context, /* ShouldBeLazy */ false);
|
|
}
|
|
|
|
ErrorOr<std::unique_ptr<LTOModule>>
|
|
LTOModule::createInLocalContext(std::unique_ptr<LLVMContext> Context,
|
|
const void *mem, size_t length,
|
|
const TargetOptions &options, StringRef path) {
|
|
StringRef Data((const char *)mem, length);
|
|
MemoryBufferRef Buffer(Data, path);
|
|
// If we own a context, we know this is being used only for symbol extraction,
|
|
// not linking. Be lazy in that case.
|
|
ErrorOr<std::unique_ptr<LTOModule>> Ret =
|
|
makeLTOModule(Buffer, options, *Context, /* ShouldBeLazy */ true);
|
|
if (Ret)
|
|
(*Ret)->OwnedContext = std::move(Context);
|
|
return Ret;
|
|
}
|
|
|
|
static ErrorOr<std::unique_ptr<Module>>
|
|
parseBitcodeFileImpl(MemoryBufferRef Buffer, LLVMContext &Context,
|
|
bool ShouldBeLazy) {
|
|
// Find the buffer.
|
|
Expected<MemoryBufferRef> MBOrErr =
|
|
IRObjectFile::findBitcodeInMemBuffer(Buffer);
|
|
if (Error E = MBOrErr.takeError()) {
|
|
std::error_code EC = errorToErrorCode(std::move(E));
|
|
Context.emitError(EC.message());
|
|
return EC;
|
|
}
|
|
|
|
if (!ShouldBeLazy) {
|
|
// Parse the full file.
|
|
return expectedToErrorOrAndEmitErrors(Context,
|
|
parseBitcodeFile(*MBOrErr, Context));
|
|
}
|
|
|
|
// Parse lazily.
|
|
return expectedToErrorOrAndEmitErrors(
|
|
Context,
|
|
getLazyBitcodeModule(*MBOrErr, Context, true /*ShouldLazyLoadMetadata*/));
|
|
}
|
|
|
|
ErrorOr<std::unique_ptr<LTOModule>>
|
|
LTOModule::makeLTOModule(MemoryBufferRef Buffer, const TargetOptions &options,
|
|
LLVMContext &Context, bool ShouldBeLazy) {
|
|
ErrorOr<std::unique_ptr<Module>> MOrErr =
|
|
parseBitcodeFileImpl(Buffer, Context, ShouldBeLazy);
|
|
if (std::error_code EC = MOrErr.getError())
|
|
return EC;
|
|
std::unique_ptr<Module> &M = *MOrErr;
|
|
|
|
std::string TripleStr = M->getTargetTriple();
|
|
if (TripleStr.empty())
|
|
TripleStr = sys::getDefaultTargetTriple();
|
|
llvm::Triple Triple(TripleStr);
|
|
|
|
// find machine architecture for this module
|
|
std::string errMsg;
|
|
const Target *march = TargetRegistry::lookupTarget(TripleStr, errMsg);
|
|
if (!march)
|
|
return make_error_code(object::object_error::arch_not_found);
|
|
|
|
// construct LTOModule, hand over ownership of module and target
|
|
SubtargetFeatures Features;
|
|
Features.getDefaultSubtargetFeatures(Triple);
|
|
std::string FeatureStr = Features.getString();
|
|
// Set a default CPU for Darwin triples.
|
|
std::string CPU;
|
|
if (Triple.isOSDarwin()) {
|
|
if (Triple.getArch() == llvm::Triple::x86_64)
|
|
CPU = "core2";
|
|
else if (Triple.getArch() == llvm::Triple::x86)
|
|
CPU = "yonah";
|
|
else if (Triple.getArch() == llvm::Triple::aarch64)
|
|
CPU = "cyclone";
|
|
}
|
|
|
|
TargetMachine *target =
|
|
march->createTargetMachine(TripleStr, CPU, FeatureStr, options, None);
|
|
|
|
std::unique_ptr<LTOModule> Ret(new LTOModule(std::move(M), Buffer, target));
|
|
Ret->parseSymbols();
|
|
Ret->parseMetadata();
|
|
|
|
return std::move(Ret);
|
|
}
|
|
|
|
/// Create a MemoryBuffer from a memory range with an optional name.
|
|
std::unique_ptr<MemoryBuffer>
|
|
LTOModule::makeBuffer(const void *mem, size_t length, StringRef name) {
|
|
const char *startPtr = (const char*)mem;
|
|
return MemoryBuffer::getMemBuffer(StringRef(startPtr, length), name, false);
|
|
}
|
|
|
|
/// objcClassNameFromExpression - Get string that the data pointer points to.
|
|
bool
|
|
LTOModule::objcClassNameFromExpression(const Constant *c, std::string &name) {
|
|
if (const ConstantExpr *ce = dyn_cast<ConstantExpr>(c)) {
|
|
Constant *op = ce->getOperand(0);
|
|
if (GlobalVariable *gvn = dyn_cast<GlobalVariable>(op)) {
|
|
Constant *cn = gvn->getInitializer();
|
|
if (ConstantDataArray *ca = dyn_cast<ConstantDataArray>(cn)) {
|
|
if (ca->isCString()) {
|
|
name = (".objc_class_name_" + ca->getAsCString()).str();
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/// addObjCClass - Parse i386/ppc ObjC class data structure.
|
|
void LTOModule::addObjCClass(const GlobalVariable *clgv) {
|
|
const ConstantStruct *c = dyn_cast<ConstantStruct>(clgv->getInitializer());
|
|
if (!c) return;
|
|
|
|
// second slot in __OBJC,__class is pointer to superclass name
|
|
std::string superclassName;
|
|
if (objcClassNameFromExpression(c->getOperand(1), superclassName)) {
|
|
auto IterBool =
|
|
_undefines.insert(std::make_pair(superclassName, NameAndAttributes()));
|
|
if (IterBool.second) {
|
|
NameAndAttributes &info = IterBool.first->second;
|
|
info.name = IterBool.first->first();
|
|
info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
|
|
info.isFunction = false;
|
|
info.symbol = clgv;
|
|
}
|
|
}
|
|
|
|
// third slot in __OBJC,__class is pointer to class name
|
|
std::string className;
|
|
if (objcClassNameFromExpression(c->getOperand(2), className)) {
|
|
auto Iter = _defines.insert(className).first;
|
|
|
|
NameAndAttributes info;
|
|
info.name = Iter->first();
|
|
info.attributes = LTO_SYMBOL_PERMISSIONS_DATA |
|
|
LTO_SYMBOL_DEFINITION_REGULAR | LTO_SYMBOL_SCOPE_DEFAULT;
|
|
info.isFunction = false;
|
|
info.symbol = clgv;
|
|
_symbols.push_back(info);
|
|
}
|
|
}
|
|
|
|
/// addObjCCategory - Parse i386/ppc ObjC category data structure.
|
|
void LTOModule::addObjCCategory(const GlobalVariable *clgv) {
|
|
const ConstantStruct *c = dyn_cast<ConstantStruct>(clgv->getInitializer());
|
|
if (!c) return;
|
|
|
|
// second slot in __OBJC,__category is pointer to target class name
|
|
std::string targetclassName;
|
|
if (!objcClassNameFromExpression(c->getOperand(1), targetclassName))
|
|
return;
|
|
|
|
auto IterBool =
|
|
_undefines.insert(std::make_pair(targetclassName, NameAndAttributes()));
|
|
|
|
if (!IterBool.second)
|
|
return;
|
|
|
|
NameAndAttributes &info = IterBool.first->second;
|
|
info.name = IterBool.first->first();
|
|
info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
|
|
info.isFunction = false;
|
|
info.symbol = clgv;
|
|
}
|
|
|
|
/// addObjCClassRef - Parse i386/ppc ObjC class list data structure.
|
|
void LTOModule::addObjCClassRef(const GlobalVariable *clgv) {
|
|
std::string targetclassName;
|
|
if (!objcClassNameFromExpression(clgv->getInitializer(), targetclassName))
|
|
return;
|
|
|
|
auto IterBool =
|
|
_undefines.insert(std::make_pair(targetclassName, NameAndAttributes()));
|
|
|
|
if (!IterBool.second)
|
|
return;
|
|
|
|
NameAndAttributes &info = IterBool.first->second;
|
|
info.name = IterBool.first->first();
|
|
info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
|
|
info.isFunction = false;
|
|
info.symbol = clgv;
|
|
}
|
|
|
|
void LTOModule::addDefinedDataSymbol(ModuleSymbolTable::Symbol Sym) {
|
|
SmallString<64> Buffer;
|
|
{
|
|
raw_svector_ostream OS(Buffer);
|
|
SymTab.printSymbolName(OS, Sym);
|
|
Buffer.c_str();
|
|
}
|
|
|
|
const GlobalValue *V = Sym.get<GlobalValue *>();
|
|
addDefinedDataSymbol(Buffer, V);
|
|
}
|
|
|
|
void LTOModule::addDefinedDataSymbol(StringRef Name, const GlobalValue *v) {
|
|
// Add to list of defined symbols.
|
|
addDefinedSymbol(Name, v, false);
|
|
|
|
if (!v->hasSection() /* || !isTargetDarwin */)
|
|
return;
|
|
|
|
// Special case i386/ppc ObjC data structures in magic sections:
|
|
// The issue is that the old ObjC object format did some strange
|
|
// contortions to avoid real linker symbols. For instance, the
|
|
// ObjC class data structure is allocated statically in the executable
|
|
// that defines that class. That data structures contains a pointer to
|
|
// its superclass. But instead of just initializing that part of the
|
|
// struct to the address of its superclass, and letting the static and
|
|
// dynamic linkers do the rest, the runtime works by having that field
|
|
// instead point to a C-string that is the name of the superclass.
|
|
// At runtime the objc initialization updates that pointer and sets
|
|
// it to point to the actual super class. As far as the linker
|
|
// knows it is just a pointer to a string. But then someone wanted the
|
|
// linker to issue errors at build time if the superclass was not found.
|
|
// So they figured out a way in mach-o object format to use an absolute
|
|
// symbols (.objc_class_name_Foo = 0) and a floating reference
|
|
// (.reference .objc_class_name_Bar) to cause the linker into erroring when
|
|
// a class was missing.
|
|
// The following synthesizes the implicit .objc_* symbols for the linker
|
|
// from the ObjC data structures generated by the front end.
|
|
|
|
// special case if this data blob is an ObjC class definition
|
|
if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(v)) {
|
|
StringRef Section = GV->getSection();
|
|
if (Section.startswith("__OBJC,__class,")) {
|
|
addObjCClass(GV);
|
|
}
|
|
|
|
// special case if this data blob is an ObjC category definition
|
|
else if (Section.startswith("__OBJC,__category,")) {
|
|
addObjCCategory(GV);
|
|
}
|
|
|
|
// special case if this data blob is the list of referenced classes
|
|
else if (Section.startswith("__OBJC,__cls_refs,")) {
|
|
addObjCClassRef(GV);
|
|
}
|
|
}
|
|
}
|
|
|
|
void LTOModule::addDefinedFunctionSymbol(ModuleSymbolTable::Symbol Sym) {
|
|
SmallString<64> Buffer;
|
|
{
|
|
raw_svector_ostream OS(Buffer);
|
|
SymTab.printSymbolName(OS, Sym);
|
|
Buffer.c_str();
|
|
}
|
|
|
|
const Function *F = cast<Function>(Sym.get<GlobalValue *>());
|
|
addDefinedFunctionSymbol(Buffer, F);
|
|
}
|
|
|
|
void LTOModule::addDefinedFunctionSymbol(StringRef Name, const Function *F) {
|
|
// add to list of defined symbols
|
|
addDefinedSymbol(Name, F, true);
|
|
}
|
|
|
|
void LTOModule::addDefinedSymbol(StringRef Name, const GlobalValue *def,
|
|
bool isFunction) {
|
|
// set alignment part log2() can have rounding errors
|
|
uint32_t align = def->getAlignment();
|
|
uint32_t attr = align ? countTrailingZeros(align) : 0;
|
|
|
|
// set permissions part
|
|
if (isFunction) {
|
|
attr |= LTO_SYMBOL_PERMISSIONS_CODE;
|
|
} else {
|
|
const GlobalVariable *gv = dyn_cast<GlobalVariable>(def);
|
|
if (gv && gv->isConstant())
|
|
attr |= LTO_SYMBOL_PERMISSIONS_RODATA;
|
|
else
|
|
attr |= LTO_SYMBOL_PERMISSIONS_DATA;
|
|
}
|
|
|
|
// set definition part
|
|
if (def->hasWeakLinkage() || def->hasLinkOnceLinkage())
|
|
attr |= LTO_SYMBOL_DEFINITION_WEAK;
|
|
else if (def->hasCommonLinkage())
|
|
attr |= LTO_SYMBOL_DEFINITION_TENTATIVE;
|
|
else
|
|
attr |= LTO_SYMBOL_DEFINITION_REGULAR;
|
|
|
|
// set scope part
|
|
if (def->hasLocalLinkage())
|
|
// Ignore visibility if linkage is local.
|
|
attr |= LTO_SYMBOL_SCOPE_INTERNAL;
|
|
else if (def->hasHiddenVisibility())
|
|
attr |= LTO_SYMBOL_SCOPE_HIDDEN;
|
|
else if (def->hasProtectedVisibility())
|
|
attr |= LTO_SYMBOL_SCOPE_PROTECTED;
|
|
else if (def->canBeOmittedFromSymbolTable())
|
|
attr |= LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN;
|
|
else
|
|
attr |= LTO_SYMBOL_SCOPE_DEFAULT;
|
|
|
|
if (def->hasComdat())
|
|
attr |= LTO_SYMBOL_COMDAT;
|
|
|
|
if (isa<GlobalAlias>(def))
|
|
attr |= LTO_SYMBOL_ALIAS;
|
|
|
|
auto Iter = _defines.insert(Name).first;
|
|
|
|
// fill information structure
|
|
NameAndAttributes info;
|
|
StringRef NameRef = Iter->first();
|
|
info.name = NameRef;
|
|
assert(NameRef.data()[NameRef.size()] == '\0');
|
|
info.attributes = attr;
|
|
info.isFunction = isFunction;
|
|
info.symbol = def;
|
|
|
|
// add to table of symbols
|
|
_symbols.push_back(info);
|
|
}
|
|
|
|
/// addAsmGlobalSymbol - Add a global symbol from module-level ASM to the
|
|
/// defined list.
|
|
void LTOModule::addAsmGlobalSymbol(StringRef name,
|
|
lto_symbol_attributes scope) {
|
|
auto IterBool = _defines.insert(name);
|
|
|
|
// only add new define if not already defined
|
|
if (!IterBool.second)
|
|
return;
|
|
|
|
NameAndAttributes &info = _undefines[IterBool.first->first()];
|
|
|
|
if (info.symbol == nullptr) {
|
|
// FIXME: This is trying to take care of module ASM like this:
|
|
//
|
|
// module asm ".zerofill __FOO, __foo, _bar_baz_qux, 0"
|
|
//
|
|
// but is gross and its mother dresses it funny. Have the ASM parser give us
|
|
// more details for this type of situation so that we're not guessing so
|
|
// much.
|
|
|
|
// fill information structure
|
|
info.name = IterBool.first->first();
|
|
info.attributes =
|
|
LTO_SYMBOL_PERMISSIONS_DATA | LTO_SYMBOL_DEFINITION_REGULAR | scope;
|
|
info.isFunction = false;
|
|
info.symbol = nullptr;
|
|
|
|
// add to table of symbols
|
|
_symbols.push_back(info);
|
|
return;
|
|
}
|
|
|
|
if (info.isFunction)
|
|
addDefinedFunctionSymbol(info.name, cast<Function>(info.symbol));
|
|
else
|
|
addDefinedDataSymbol(info.name, info.symbol);
|
|
|
|
_symbols.back().attributes &= ~LTO_SYMBOL_SCOPE_MASK;
|
|
_symbols.back().attributes |= scope;
|
|
}
|
|
|
|
/// addAsmGlobalSymbolUndef - Add a global symbol from module-level ASM to the
|
|
/// undefined list.
|
|
void LTOModule::addAsmGlobalSymbolUndef(StringRef name) {
|
|
auto IterBool = _undefines.insert(std::make_pair(name, NameAndAttributes()));
|
|
|
|
_asm_undefines.push_back(IterBool.first->first());
|
|
|
|
// we already have the symbol
|
|
if (!IterBool.second)
|
|
return;
|
|
|
|
uint32_t attr = LTO_SYMBOL_DEFINITION_UNDEFINED;
|
|
attr |= LTO_SYMBOL_SCOPE_DEFAULT;
|
|
NameAndAttributes &info = IterBool.first->second;
|
|
info.name = IterBool.first->first();
|
|
info.attributes = attr;
|
|
info.isFunction = false;
|
|
info.symbol = nullptr;
|
|
}
|
|
|
|
/// Add a symbol which isn't defined just yet to a list to be resolved later.
|
|
void LTOModule::addPotentialUndefinedSymbol(ModuleSymbolTable::Symbol Sym,
|
|
bool isFunc) {
|
|
SmallString<64> name;
|
|
{
|
|
raw_svector_ostream OS(name);
|
|
SymTab.printSymbolName(OS, Sym);
|
|
name.c_str();
|
|
}
|
|
|
|
auto IterBool = _undefines.insert(std::make_pair(name, NameAndAttributes()));
|
|
|
|
// we already have the symbol
|
|
if (!IterBool.second)
|
|
return;
|
|
|
|
NameAndAttributes &info = IterBool.first->second;
|
|
|
|
info.name = IterBool.first->first();
|
|
|
|
const GlobalValue *decl = Sym.dyn_cast<GlobalValue *>();
|
|
|
|
if (decl->hasExternalWeakLinkage())
|
|
info.attributes = LTO_SYMBOL_DEFINITION_WEAKUNDEF;
|
|
else
|
|
info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
|
|
|
|
info.isFunction = isFunc;
|
|
info.symbol = decl;
|
|
}
|
|
|
|
void LTOModule::parseSymbols() {
|
|
for (auto Sym : SymTab.symbols()) {
|
|
auto *GV = Sym.dyn_cast<GlobalValue *>();
|
|
uint32_t Flags = SymTab.getSymbolFlags(Sym);
|
|
if (Flags & object::BasicSymbolRef::SF_FormatSpecific)
|
|
continue;
|
|
|
|
bool IsUndefined = Flags & object::BasicSymbolRef::SF_Undefined;
|
|
|
|
if (!GV) {
|
|
SmallString<64> Buffer;
|
|
{
|
|
raw_svector_ostream OS(Buffer);
|
|
SymTab.printSymbolName(OS, Sym);
|
|
Buffer.c_str();
|
|
}
|
|
StringRef Name(Buffer);
|
|
|
|
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;
|
|
}
|
|
|
|
auto *F = dyn_cast<Function>(GV);
|
|
if (IsUndefined) {
|
|
addPotentialUndefinedSymbol(Sym, F != nullptr);
|
|
continue;
|
|
}
|
|
|
|
if (F) {
|
|
addDefinedFunctionSymbol(Sym);
|
|
continue;
|
|
}
|
|
|
|
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(),
|
|
e = _undefines.end(); u != e; ++u) {
|
|
// If this symbol also has a definition, then don't make an undefine because
|
|
// it is a tentative definition.
|
|
if (_defines.count(u->getKey())) continue;
|
|
NameAndAttributes info = u->getValue();
|
|
_symbols.push_back(info);
|
|
}
|
|
}
|
|
|
|
/// parseMetadata - Parse metadata from the module
|
|
void LTOModule::parseMetadata() {
|
|
raw_string_ostream OS(LinkerOpts);
|
|
|
|
// Linker Options
|
|
if (NamedMDNode *LinkerOptions =
|
|
getModule().getNamedMetadata("llvm.linker.options")) {
|
|
for (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) {
|
|
MDNode *MDOptions = LinkerOptions->getOperand(i);
|
|
for (unsigned ii = 0, ie = MDOptions->getNumOperands(); ii != ie; ++ii) {
|
|
MDString *MDOption = cast<MDString>(MDOptions->getOperand(ii));
|
|
OS << " " << MDOption->getString();
|
|
}
|
|
}
|
|
}
|
|
|
|
// Globals - we only need to do this for COFF.
|
|
const Triple TT(_target->getTargetTriple());
|
|
if (!TT.isOSBinFormatCOFF())
|
|
return;
|
|
Mangler M;
|
|
for (const NameAndAttributes &Sym : _symbols) {
|
|
if (!Sym.symbol)
|
|
continue;
|
|
emitLinkerFlagsForGlobalCOFF(OS, Sym.symbol, TT, M);
|
|
}
|
|
|
|
// Add other interesting metadata here.
|
|
}
|