maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity
llvm-project/llvm/tools/lto/LTOModule.cpp

913 lines
30 KiB
C++
Raw Blame History

//===-- 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 "LTOModule.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/LLVMContext.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/MCStreamer.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/MC/MCTargetAsmParser.h"
#include "llvm/MC/SubtargetFeature.h"
#include "llvm/Support/CommandLine.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/Support/system_error.h"
#include "llvm/Target/TargetRegisterInfo.h"
using namespace llvm;
static cl::opt<bool>
EnableFPMAD("enable-fp-mad",
cl::desc("Enable less precise MAD instructions to be generated"),
cl::init(false));
static cl::opt<bool>
DisableFPElim("disable-fp-elim",
cl::desc("Disable frame pointer elimination optimization"),
cl::init(false));
static cl::opt<bool>
DisableFPElimNonLeaf("disable-non-leaf-fp-elim",
cl::desc("Disable frame pointer elimination optimization for non-leaf funcs"),
cl::init(false));
static cl::opt<bool>
EnableUnsafeFPMath("enable-unsafe-fp-math",
cl::desc("Enable optimizations that may decrease FP precision"),
cl::init(false));
static cl::opt<bool>
EnableNoInfsFPMath("enable-no-infs-fp-math",
cl::desc("Enable FP math optimizations that assume no +-Infs"),
cl::init(false));
static cl::opt<bool>
EnableNoNaNsFPMath("enable-no-nans-fp-math",
cl::desc("Enable FP math optimizations that assume no NaNs"),
cl::init(false));
static cl::opt<bool>
EnableHonorSignDependentRoundingFPMath("enable-sign-dependent-rounding-fp-math",
cl::Hidden,
cl::desc("Force codegen to assume rounding mode can change dynamically"),
cl::init(false));
static cl::opt<bool>
GenerateSoftFloatCalls("soft-float",
cl::desc("Generate software floating point library calls"),
cl::init(false));
static cl::opt<llvm::FloatABI::ABIType>
FloatABIForCalls("float-abi",
cl::desc("Choose float ABI type"),
cl::init(FloatABI::Default),
cl::values(
clEnumValN(FloatABI::Default, "default",
"Target default float ABI type"),
clEnumValN(FloatABI::Soft, "soft",
"Soft float ABI (implied by -soft-float)"),
clEnumValN(FloatABI::Hard, "hard",
"Hard float ABI (uses FP registers)"),
clEnumValEnd));
static cl::opt<llvm::FPOpFusion::FPOpFusionMode>
FuseFPOps("fp-contract",
cl::desc("Enable aggresive formation of fused FP ops"),
cl::init(FPOpFusion::Standard),
cl::values(
clEnumValN(FPOpFusion::Fast, "fast",
"Fuse FP ops whenever profitable"),
clEnumValN(FPOpFusion::Standard, "on",
"Only fuse 'blessed' FP ops."),
clEnumValN(FPOpFusion::Strict, "off",
"Only fuse FP ops when the result won't be effected."),
clEnumValEnd));
static cl::opt<bool>
DontPlaceZerosInBSS("nozero-initialized-in-bss",
cl::desc("Don't place zero-initialized symbols into bss section"),
cl::init(false));
static cl::opt<bool>
EnableGuaranteedTailCallOpt("tailcallopt",
cl::desc("Turn fastcc calls into tail calls by (potentially) changing ABI."),
cl::init(false));
static cl::opt<bool>
DisableTailCalls("disable-tail-calls",
cl::desc("Never emit tail calls"),
cl::init(false));
static cl::opt<unsigned>
OverrideStackAlignment("stack-alignment",
cl::desc("Override default stack alignment"),
cl::init(0));
static cl::opt<bool>
EnableRealignStack("realign-stack",
cl::desc("Realign stack if needed"),
cl::init(true));
static cl::opt<std::string>
TrapFuncName("trap-func", cl::Hidden,
cl::desc("Emit a call to trap function rather than a trap instruction"),
cl::init(""));
static cl::opt<bool>
EnablePIE("enable-pie",
cl::desc("Assume the creation of a position independent executable."),
cl::init(false));
static cl::opt<bool>
SegmentedStacks("segmented-stacks",
cl::desc("Use segmented stacks if possible."),
cl::init(false));
static cl::opt<bool>
UseInitArray("use-init-array",
cl::desc("Use .init_array instead of .ctors."),
cl::init(false));
static cl::opt<unsigned>
SSPBufferSize("stack-protector-buffer-size", cl::init(8),
cl::desc("Lower bound for a buffer to be considered for "
"stack protection"));
LTOModule::LTOModule(llvm::Module *m, llvm::TargetMachine *t)
: _module(m), _target(t),
_context(*_target->getMCAsmInfo(), *_target->getRegisterInfo(), NULL),
_mangler(_context, *_target->getDataLayout()) {}
/// isBitcodeFile - Returns 'true' if the file (or memory contents) is LLVM
/// bitcode.
bool LTOModule::isBitcodeFile(const void *mem, size_t length) {
return llvm::sys::IdentifyFileType((const char*)mem, length)
== llvm::sys::Bitcode_FileType;
}
bool LTOModule::isBitcodeFile(const char *path) {
return llvm::sys::Path(path).isBitcodeFile();
}
/// isBitcodeFileForTarget - Returns 'true' if the file (or memory contents) is
/// LLVM bitcode for the specified triple.
bool LTOModule::isBitcodeFileForTarget(const void *mem, size_t length,
const char *triplePrefix) {
MemoryBuffer *buffer = makeBuffer(mem, length);
if (!buffer)
return false;
return isTargetMatch(buffer, triplePrefix);
}
bool LTOModule::isBitcodeFileForTarget(const char *path,
const char *triplePrefix) {
OwningPtr<MemoryBuffer> buffer;
if (MemoryBuffer::getFile(path, buffer))
return false;
return isTargetMatch(buffer.take(), triplePrefix);
}
/// isTargetMatch - Returns 'true' if the memory buffer is for the specified
/// target triple.
bool LTOModule::isTargetMatch(MemoryBuffer *buffer, const char *triplePrefix) {
std::string Triple = getBitcodeTargetTriple(buffer, getGlobalContext());
delete buffer;
return strncmp(Triple.c_str(), triplePrefix, strlen(triplePrefix)) == 0;
}
/// makeLTOModule - Create an LTOModule. N.B. These methods take ownership of
/// the buffer.
LTOModule *LTOModule::makeLTOModule(const char *path, std::string &errMsg) {
OwningPtr<MemoryBuffer> buffer;
if (error_code ec = MemoryBuffer::getFile(path, buffer)) {
errMsg = ec.message();
return NULL;
}
return makeLTOModule(buffer.take(), errMsg);
}
LTOModule *LTOModule::makeLTOModule(int fd, const char *path,
size_t size, std::string &errMsg) {
return makeLTOModule(fd, path, size, size, 0, errMsg);
}
LTOModule *LTOModule::makeLTOModule(int fd, const char *path,
size_t file_size,
size_t map_size,
off_t offset,
std::string &errMsg) {
OwningPtr<MemoryBuffer> buffer;
if (error_code ec = MemoryBuffer::getOpenFile(fd, path, buffer, file_size,
map_size, offset, false)) {
errMsg = ec.message();
return NULL;
}
return makeLTOModule(buffer.take(), errMsg);
}
LTOModule *LTOModule::makeLTOModule(const void *mem, size_t length,
std::string &errMsg) {
OwningPtr<MemoryBuffer> buffer(makeBuffer(mem, length));
if (!buffer)
return NULL;
return makeLTOModule(buffer.take(), errMsg);
}
void LTOModule::getTargetOptions(TargetOptions &Options) {
Options.LessPreciseFPMADOption = EnableFPMAD;
Options.NoFramePointerElim = DisableFPElim;
Options.NoFramePointerElimNonLeaf = DisableFPElimNonLeaf;
Options.AllowFPOpFusion = FuseFPOps;
Options.UnsafeFPMath = EnableUnsafeFPMath;
Options.NoInfsFPMath = EnableNoInfsFPMath;
Options.NoNaNsFPMath = EnableNoNaNsFPMath;
Options.HonorSignDependentRoundingFPMathOption =
EnableHonorSignDependentRoundingFPMath;
Options.UseSoftFloat = GenerateSoftFloatCalls;
if (FloatABIForCalls != FloatABI::Default)
Options.FloatABIType = FloatABIForCalls;
Options.NoZerosInBSS = DontPlaceZerosInBSS;
Options.GuaranteedTailCallOpt = EnableGuaranteedTailCallOpt;
Options.DisableTailCalls = DisableTailCalls;
Options.StackAlignmentOverride = OverrideStackAlignment;
Options.RealignStack = EnableRealignStack;
Options.TrapFuncName = TrapFuncName;
Options.PositionIndependentExecutable = EnablePIE;
Options.EnableSegmentedStacks = SegmentedStacks;
Options.UseInitArray = UseInitArray;
Options.SSPBufferSize = SSPBufferSize;
}
LTOModule *LTOModule::makeLTOModule(MemoryBuffer *buffer,
std::string &errMsg) {
static bool Initialized = false;
if (!Initialized) {
InitializeAllTargets();
InitializeAllTargetMCs();
InitializeAllAsmParsers();
Initialized = true;
}
// parse bitcode buffer
OwningPtr<Module> m(getLazyBitcodeModule(buffer, getGlobalContext(),
&errMsg));
if (!m) {
delete buffer;
return NULL;
}
std::string TripleStr = m->getTargetTriple();
if (TripleStr.empty())
TripleStr = sys::getDefaultTargetTriple();
llvm::Triple Triple(TripleStr);
// find machine architecture for this module
const Target *march = TargetRegistry::lookupTarget(TripleStr, errMsg);
if (!march)
return NULL;
// 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";
}
TargetOptions Options;
getTargetOptions(Options);
TargetMachine *target = march->createTargetMachine(TripleStr, CPU, FeatureStr,
Options);
LTOModule *Ret = new LTOModule(m.take(), target);
if (Ret->parseSymbols(errMsg)) {
delete Ret;
return NULL;
}
return Ret;
}
/// makeBuffer - Create a MemoryBuffer from a memory range.
MemoryBuffer *LTOModule::makeBuffer(const void *mem, size_t length) {
const char *startPtr = (const char*)mem;
return MemoryBuffer::getMemBuffer(StringRef(startPtr, length), "", 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)) {
NameAndAttributes info;
StringMap<NameAndAttributes>::value_type &entry =
_undefines.GetOrCreateValue(superclassName);
if (!entry.getValue().name) {
const char *symbolName = entry.getKey().data();
info.name = symbolName;
info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
info.isFunction = false;
info.symbol = clgv;
entry.setValue(info);
}
}
// third slot in __OBJC,__class is pointer to class name
std::string className;
if (objcClassNameFromExpression(c->getOperand(2), className)) {
StringSet::value_type &entry = _defines.GetOrCreateValue(className);
entry.setValue(1);
NameAndAttributes info;
info.name = entry.getKey().data();
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;
NameAndAttributes info;
StringMap<NameAndAttributes>::value_type &entry =
_undefines.GetOrCreateValue(targetclassName);
if (entry.getValue().name)
return;
const char *symbolName = entry.getKey().data();
info.name = symbolName;
info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
info.isFunction = false;
info.symbol = clgv;
entry.setValue(info);
}
/// addObjCClassRef - Parse i386/ppc ObjC class list data structure.
void LTOModule::addObjCClassRef(const GlobalVariable *clgv) {
std::string targetclassName;
if (!objcClassNameFromExpression(clgv->getInitializer(), targetclassName))
return;
NameAndAttributes info;
StringMap<NameAndAttributes>::value_type &entry =
_undefines.GetOrCreateValue(targetclassName);
if (entry.getValue().name)
return;
const char *symbolName = entry.getKey().data();
info.name = symbolName;
info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
info.isFunction = false;
info.symbol = clgv;
entry.setValue(info);
}
/// addDefinedDataSymbol - Add a data symbol as defined to the list.
void LTOModule::addDefinedDataSymbol(const GlobalValue *v) {
// Add to list of defined symbols.
addDefinedSymbol(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 (v->getSection().compare(0, 15, "__OBJC,__class,") == 0) {
if (const GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) {
addObjCClass(gv);
}
}
// special case if this data blob is an ObjC category definition
else if (v->getSection().compare(0, 18, "__OBJC,__category,") == 0) {
if (const GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) {
addObjCCategory(gv);
}
}
// special case if this data blob is the list of referenced classes
else if (v->getSection().compare(0, 18, "__OBJC,__cls_refs,") == 0) {
if (const GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) {
addObjCClassRef(gv);
}
}
}
/// addDefinedFunctionSymbol - Add a function symbol as defined to the list.
void LTOModule::addDefinedFunctionSymbol(const Function *f) {
// add to list of defined symbols
addDefinedSymbol(f, true);
}
/// addDefinedSymbol - Add a defined symbol to the list.
void LTOModule::addDefinedSymbol(const GlobalValue *def, bool isFunction) {
// ignore all llvm.* symbols
if (def->getName().startswith("llvm."))
return;
// string is owned by _defines
SmallString<64> Buffer;
_mangler.getNameWithPrefix(Buffer, def, false);
// set alignment part log2() can have rounding errors
uint32_t align = def->getAlignment();
uint32_t attr = align ? CountTrailingZeros_32(def->getAlignment()) : 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() ||
def->hasLinkerPrivateWeakLinkage())
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->hasHiddenVisibility())
attr |= LTO_SYMBOL_SCOPE_HIDDEN;
else if (def->hasProtectedVisibility())
attr |= LTO_SYMBOL_SCOPE_PROTECTED;
else if (def->hasExternalLinkage() || def->hasWeakLinkage() ||
def->hasLinkOnceLinkage() || def->hasCommonLinkage() ||
def->hasLinkerPrivateWeakLinkage())
attr |= LTO_SYMBOL_SCOPE_DEFAULT;
else if (def->hasLinkOnceODRAutoHideLinkage())
attr |= LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN;
else
attr |= LTO_SYMBOL_SCOPE_INTERNAL;
StringSet::value_type &entry = _defines.GetOrCreateValue(Buffer);
entry.setValue(1);
// fill information structure
NameAndAttributes info;
StringRef Name = entry.getKey();
info.name = Name.data();
assert(info.name[Name.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(const char *name,
lto_symbol_attributes scope) {
StringSet::value_type &entry = _defines.GetOrCreateValue(name);
// only add new define if not already defined
if (entry.getValue())
return;
entry.setValue(1);
NameAndAttributes &info = _undefines[entry.getKey().data()];
if (info.symbol == 0) {
// 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 = entry.getKey().data();
info.attributes =
LTO_SYMBOL_PERMISSIONS_DATA | LTO_SYMBOL_DEFINITION_REGULAR | scope;
info.isFunction = false;
info.symbol = 0;
// add to table of symbols
_symbols.push_back(info);
return;
}
if (info.isFunction)
addDefinedFunctionSymbol(cast<Function>(info.symbol));
else
addDefinedDataSymbol(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(const char *name) {
StringMap<NameAndAttributes>::value_type &entry =
_undefines.GetOrCreateValue(name);
_asm_undefines.push_back(entry.getKey().data());
// we already have the symbol
if (entry.getValue().name)
return;
uint32_t attr = LTO_SYMBOL_DEFINITION_UNDEFINED;;
attr |= LTO_SYMBOL_SCOPE_DEFAULT;
NameAndAttributes info;
info.name = entry.getKey().data();
info.attributes = attr;
info.isFunction = false;
info.symbol = 0;
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;
SmallString<64> name;
_mangler.getNameWithPrefix(name, decl, false);
StringMap<NameAndAttributes>::value_type &entry =
_undefines.GetOrCreateValue(name);
// we already have the symbol
if (entry.getValue().name)
return;
NameAndAttributes info;
info.name = entry.getKey().data();
if (decl->hasExternalWeakLinkage())
info.attributes = LTO_SYMBOL_DEFINITION_WEAKUNDEF;
else
info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
info.isFunction = isFunc;
info.symbol = decl;
entry.setValue(info);
}
namespace {
class RecordStreamer : public MCStreamer {
public:
enum State { NeverSeen, Global, Defined, DefinedGlobal, Used };
private:
StringMap<State> Symbols;
void markDefined(const MCSymbol &Symbol) {
State &S = Symbols[Symbol.getName()];
switch (S) {
case DefinedGlobal:
case Global:
S = DefinedGlobal;
break;
case NeverSeen:
case Defined:
case Used:
S = Defined;
break;
}
}
void markGlobal(const MCSymbol &Symbol) {
State &S = Symbols[Symbol.getName()];
switch (S) {
case DefinedGlobal:
case Defined:
S = DefinedGlobal;
break;
case NeverSeen:
case Global:
case Used:
S = Global;
break;
}
}
void markUsed(const MCSymbol &Symbol) {
State &S = Symbols[Symbol.getName()];
switch (S) {
case DefinedGlobal:
case Defined:
case Global:
break;
case NeverSeen:
case Used:
S = Used;
break;
}
}
// FIXME: mostly copied for the obj streamer.
void AddValueSymbols(const MCExpr *Value) {
switch (Value->getKind()) {
case MCExpr::Target:
// FIXME: What should we do in here?
break;
case MCExpr::Constant:
break;
case MCExpr::Binary: {
const MCBinaryExpr *BE = cast<MCBinaryExpr>(Value);
AddValueSymbols(BE->getLHS());
AddValueSymbols(BE->getRHS());
break;
}
case MCExpr::SymbolRef:
markUsed(cast<MCSymbolRefExpr>(Value)->getSymbol());
break;
case MCExpr::Unary:
AddValueSymbols(cast<MCUnaryExpr>(Value)->getSubExpr());
break;
}
}
public:
typedef StringMap<State>::const_iterator const_iterator;
const_iterator begin() {
return Symbols.begin();
}
const_iterator end() {
return Symbols.end();
}
RecordStreamer(MCContext &Context) : MCStreamer(Context) {}
virtual void EmitInstruction(const MCInst &Inst) {
// Scan for values.
for (unsigned i = Inst.getNumOperands(); i--; )
if (Inst.getOperand(i).isExpr())
AddValueSymbols(Inst.getOperand(i).getExpr());
}
virtual void EmitLabel(MCSymbol *Symbol) {
Symbol->setSection(*getCurrentSection());
markDefined(*Symbol);
}
virtual void EmitDebugLabel(MCSymbol *Symbol) {
EmitLabel(Symbol);
}
virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
// FIXME: should we handle aliases?
markDefined(*Symbol);
}
virtual void EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) {
if (Attribute == MCSA_Global)
markGlobal(*Symbol);
}
virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
uint64_t Size , unsigned ByteAlignment) {
markDefined(*Symbol);
}
virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
unsigned ByteAlignment) {
markDefined(*Symbol);
}
virtual void EmitBundleAlignMode(unsigned AlignPow2) {}
virtual void EmitBundleLock(bool AlignToEnd) {}
virtual void EmitBundleUnlock() {}
// Noop calls.
virtual void ChangeSection(const MCSection *Section) {}
virtual void InitToTextSection() {}
virtual void InitSections() {}
virtual void EmitAssemblerFlag(MCAssemblerFlag Flag) {}
virtual void EmitThumbFunc(MCSymbol *Func) {}
virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {}
virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {}
virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol) {}
virtual void EmitCOFFSymbolStorageClass(int StorageClass) {}
virtual void EmitCOFFSymbolType(int Type) {}
virtual void EndCOFFSymbolDef() {}
virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {}
virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
unsigned ByteAlignment) {}
virtual void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
uint64_t Size, unsigned ByteAlignment) {}
virtual void EmitBytes(StringRef Data, unsigned AddrSpace) {}
virtual void EmitValueImpl(const MCExpr *Value, unsigned Size,
unsigned AddrSpace) {}
virtual void EmitULEB128Value(const MCExpr *Value) {}
virtual void EmitSLEB128Value(const MCExpr *Value) {}
virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
unsigned ValueSize,
unsigned MaxBytesToEmit) {}
virtual void EmitCodeAlignment(unsigned ByteAlignment,
unsigned MaxBytesToEmit) {}
virtual bool EmitValueToOffset(const MCExpr *Offset,
unsigned char Value ) { return false; }
virtual void EmitFileDirective(StringRef Filename) {}
virtual void EmitDwarfAdvanceLineAddr(int64_t LineDelta,
const MCSymbol *LastLabel,
const MCSymbol *Label,
unsigned PointerSize) {}
virtual void FinishImpl() {}
};
} // end anonymous namespace
/// 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;
OwningPtr<RecordStreamer> Streamer(new RecordStreamer(_context));
MemoryBuffer *Buffer = MemoryBuffer::getMemBuffer(inlineAsm);
SourceMgr SrcMgr;
SrcMgr.AddNewSourceBuffer(Buffer, SMLoc());
OwningPtr<MCAsmParser> Parser(createMCAsmParser(SrcMgr,
_context, *Streamer,
*_target->getMCAsmInfo()));
const Target &T = _target->getTarget();
OwningPtr<MCSubtargetInfo>
STI(T.createMCSubtargetInfo(_target->getTargetTriple(),
_target->getTargetCPU(),
_target->getTargetFeatureString()));
OwningPtr<MCTargetAsmParser> TAP(T.createMCAsmParser(*STI, *Parser.get()));
if (!TAP) {
errMsg = "target " + std::string(T.getName()) +
" does not define AsmParser.";
return true;
}
Parser->setTargetParser(*TAP);
if (Parser->Run(false))
return true;
for (RecordStreamer::const_iterator i = Streamer->begin(),
e = Streamer->end(); i != e; ++i) {
StringRef Key = i->first();
RecordStreamer::State Value = i->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);
}
// 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);
}
// add asm globals
if (addAsmGlobalSymbols(errMsg))
return true;
// add aliases
for (Module::alias_iterator a = _module->alias_begin(),
e = _module->alias_end(); a != e; ++a) {
if (isDeclaration(*a->getAliasedGlobal()))
// Is an alias to a declaration.
addPotentialUndefinedSymbol(a, false);
else
addDefinedDataSymbol(a);
}
// 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);
}
return false;
}
Reference in New Issue View Git Blame Copy Permalink