/// Canonicalize whitespaces in the input file. Line endings are replaced
/// with UNIX-style '\n'.
///
/// \param PreserveHorizontal Don't squash consecutive horizontal whitespace
/// characters to a single space.
static MemoryBuffer *CanonicalizeInputFile(MemoryBuffer *MB,
bool PreserveHorizontal) {
SmallString<128> NewFile;
NewFile.reserve(MB->getBufferSize());
for (const char *Ptr = MB->getBufferStart(), *End = MB->getBufferEnd();
Ptr != End; ++Ptr) {
// Eliminate trailing dosish \r.
if (Ptr <= End - 2 && Ptr[0] == '\r' && Ptr[1] == '\n') {
continue;
}
// If current char is not a horizontal whitespace or if horizontal
// whitespace canonicalization is disabled, dump it to output as is.
if (PreserveHorizontal || (*Ptr != ' ' && *Ptr != '\t')) {
NewFile.push_back(*Ptr);
continue;
}
// Otherwise, add one space and advance over neighboring space.
NewFile.push_back(' ');
while (Ptr+1 != End &&
(Ptr[1] == ' ' || Ptr[1] == '\t'))
++Ptr;
}
// Free the old buffer and return a new one.
MemoryBuffer *MB2 =
MemoryBuffer::getMemBufferCopy(NewFile.str(), MB->getBufferIdentifier());
delete MB;
return MB2;
}
/// CanonicalizeInputFile - Remove duplicate horizontal space from the specified
/// memory buffer, free it, and return a new one.
static MemoryBuffer *CanonicalizeInputFile(MemoryBuffer *MB) {
SmallString<128> NewFile;
NewFile.reserve(MB->getBufferSize());
for (const char *Ptr = MB->getBufferStart(), *End = MB->getBufferEnd();
Ptr != End; ++Ptr) {
// If C is not a horizontal whitespace, skip it.
if (*Ptr != ' ' && *Ptr != '\t') {
NewFile.push_back(*Ptr);
continue;
}
// Otherwise, add one space and advance over neighboring space.
NewFile.push_back(' ');
while (Ptr+1 != End &&
(Ptr[1] == ' ' || Ptr[1] == '\t'))
++Ptr;
}
// Free the old buffer and return a new one.
MemoryBuffer *MB2 =
MemoryBuffer::getMemBufferCopy(NewFile.str(), MB->getBufferIdentifier());
delete MB;
return MB2;
}
const X86Subtarget *
X86TargetMachine::getSubtargetImpl(const Function &F) const {
Attribute CPUAttr = F.getFnAttribute("target-cpu");
Attribute FSAttr = F.getFnAttribute("target-features");
StringRef CPU = !CPUAttr.hasAttribute(Attribute::None)
? CPUAttr.getValueAsString()
: (StringRef)TargetCPU;
StringRef FS = !FSAttr.hasAttribute(Attribute::None)
? FSAttr.getValueAsString()
: (StringRef)TargetFS;
SmallString<512> Key;
Key.reserve(CPU.size() + FS.size());
Key += CPU;
Key += FS;
// FIXME: This is related to the code below to reset the target options,
// we need to know whether or not the soft float flag is set on the
// function before we can generate a subtarget. We also need to use
// it as a key for the subtarget since that can be the only difference
// between two functions.
bool SoftFloat =
F.getFnAttribute("use-soft-float").getValueAsString() == "true";
// If the soft float attribute is set on the function turn on the soft float
// subtarget feature.
if (SoftFloat)
Key += FS.empty() ? "+soft-float" : ",+soft-float";
FS = Key.substr(CPU.size());
auto &I = SubtargetMap[Key];
if (!I) {
// This needs to be done before we create a new subtarget since any
// creation will depend on the TM and the code generation flags on the
// function that reside in TargetOptions.
resetTargetOptions(F);
I = llvm::make_unique<X86Subtarget>(TargetTriple, CPU, FS, *this,
Options.StackAlignmentOverride);
#ifndef LLVM_BUILD_GLOBAL_ISEL
GISelAccessor *GISel = new GISelAccessor();
#else
X86GISelActualAccessor *GISel = new X86GISelActualAccessor();
GISel->CallLoweringInfo.reset(new X86CallLowering(*I->getTargetLowering()));
GISel->Legalizer.reset(new X86LegalizerInfo(*I, *this));
auto *RBI = new X86RegisterBankInfo(*I->getRegisterInfo());
GISel->RegBankInfo.reset(RBI);
GISel->InstSelector.reset(createX86InstructionSelector(
*this, *I, *RBI));
#endif
I->setGISelAccessor(*GISel);
}
return I.get();
}
void LTOCodeGenerator::applyScopeRestrictions() {
if (ScopeRestrictionsDone)
return;
// Declare a callback for the internalize pass that will ask for every
// candidate GlobalValue if it can be internalized or not.
SmallString<64> MangledName;
auto mustPreserveGV = [&](const GlobalValue &GV) -> bool {
// Unnamed globals can't be mangled, but they can't be preserved either.
if (!GV.hasName())
return false;
// Need to mangle the GV as the "MustPreserveSymbols" StringSet is filled
// with the linker supplied name, which on Darwin includes a leading
// underscore.
MangledName.clear();
MangledName.reserve(GV.getName().size() + 1);
Mangler::getNameWithPrefix(MangledName, GV.getName(),
MergedModule->getDataLayout());
return MustPreserveSymbols.count(MangledName);
};
// Preserve linkonce value on linker request
preserveDiscardableGVs(*MergedModule, mustPreserveGV);
if (!ShouldInternalize)
return;
if (ShouldRestoreGlobalsLinkage) {
// Record the linkage type of non-local symbols so they can be restored
// prior
// to module splitting.
auto RecordLinkage = [&](const GlobalValue &GV) {
if (!GV.hasAvailableExternallyLinkage() && !GV.hasLocalLinkage() &&
GV.hasName())
ExternalSymbols.insert(std::make_pair(GV.getName(), GV.getLinkage()));
};
for (auto &GV : *MergedModule)
RecordLinkage(GV);
for (auto &GV : MergedModule->globals())
RecordLinkage(GV);
for (auto &GV : MergedModule->aliases())
RecordLinkage(GV);
}
// Update the llvm.compiler_used globals to force preserving libcalls and
// symbols referenced from asm
updateCompilerUsed(*MergedModule, *TargetMach, AsmUndefinedRefs);
internalizeModule(*MergedModule, mustPreserveGV);
ScopeRestrictionsDone = true;
}
static ErrorOr<std::unique_ptr<MemoryBuffer>>
getMemoryBufferForStream(int FD, const Twine &BufferName) {
const ssize_t ChunkSize = 4096*4;
SmallString<ChunkSize> Buffer;
ssize_t ReadBytes;
// Read into Buffer until we hit EOF.
do {
Buffer.reserve(Buffer.size() + ChunkSize);
ReadBytes = read(FD, Buffer.end(), ChunkSize);
if (ReadBytes == -1) {
if (errno == EINTR) continue;
return std::error_code(errno, std::generic_category());
}
Buffer.set_size(Buffer.size() + ReadBytes);
} while (ReadBytes != 0);
return MemoryBuffer::getMemBufferCopy(Buffer, BufferName);
}
const X86Subtarget *
X86TargetMachine::getSubtargetImpl(const Function &F) const {
Attribute CPUAttr = F.getFnAttribute("target-cpu");
Attribute FSAttr = F.getFnAttribute("target-features");
StringRef CPU = !CPUAttr.hasAttribute(Attribute::None)
? CPUAttr.getValueAsString()
: (StringRef)TargetCPU;
StringRef FS = !FSAttr.hasAttribute(Attribute::None)
? FSAttr.getValueAsString()
: (StringRef)TargetFS;
SmallString<512> Key;
Key.reserve(CPU.size() + FS.size());
Key += CPU;
Key += FS;
// FIXME: This is related to the code below to reset the target options,
// we need to know whether or not the soft float flag is set on the
// function before we can generate a subtarget. We also need to use
// it as a key for the subtarget since that can be the only difference
// between two functions.
bool SoftFloat =
F.getFnAttribute("use-soft-float").getValueAsString() == "true";
// If the soft float attribute is set on the function turn on the soft float
// subtarget feature.
if (SoftFloat)
Key += FS.empty() ? "+soft-float" : ",+soft-float";
FS = Key.substr(CPU.size());
auto &I = SubtargetMap[Key];
if (!I) {
// This needs to be done before we create a new subtarget since any
// creation will depend on the TM and the code generation flags on the
// function that reside in TargetOptions.
resetTargetOptions(F);
I = llvm::make_unique<X86Subtarget>(TargetTriple, CPU, FS, *this,
Options.StackAlignmentOverride);
}
return I.get();
}
static error_code getMemoryBufferForStream(int FD,
StringRef BufferName,
std::unique_ptr<MemoryBuffer> &Result) {
const ssize_t ChunkSize = 4096*4;
SmallString<ChunkSize> Buffer;
ssize_t ReadBytes;
// Read into Buffer until we hit EOF.
do {
Buffer.reserve(Buffer.size() + ChunkSize);
ReadBytes = read(FD, Buffer.end(), ChunkSize);
if (ReadBytes == -1) {
if (errno == EINTR) continue;
return error_code(errno, posix_category());
}
Buffer.set_size(Buffer.size() + ReadBytes);
} while (ReadBytes != 0);
Result.reset(MemoryBuffer::getMemBufferCopy(Buffer, BufferName));
return error_code::success();
}
error_code MemoryBuffer::getSTDIN(OwningPtr<MemoryBuffer> &result) {
// Read in all of the data from stdin, we cannot mmap stdin.
//
// FIXME: That isn't necessarily true, we should try to mmap stdin and
// fallback if it fails.
sys::Program::ChangeStdinToBinary();
const ssize_t ChunkSize = 4096*4;
SmallString<ChunkSize> Buffer;
ssize_t ReadBytes;
// Read into Buffer until we hit EOF.
do {
Buffer.reserve(Buffer.size() + ChunkSize);
ReadBytes = read(0, Buffer.end(), ChunkSize);
if (ReadBytes == -1) {
if (errno == EINTR) continue;
return error_code(errno, posix_category());
}
Buffer.set_size(Buffer.size() + ReadBytes);
} while (ReadBytes != 0);
result.reset(getMemBufferCopy(Buffer, "<stdin>"));
return error_code::success();
}
const X86Subtarget *
X86TargetMachine::getSubtargetImpl(const Function &F) const {
Attribute CPUAttr = F.getFnAttribute("target-cpu");
Attribute FSAttr = F.getFnAttribute("target-features");
StringRef CPU = !CPUAttr.hasAttribute(Attribute::None)
? CPUAttr.getValueAsString()
: (StringRef)TargetCPU;
StringRef FS = !FSAttr.hasAttribute(Attribute::None)
? FSAttr.getValueAsString()
: (StringRef)TargetFS;
SmallString<512> Key;
Key.reserve(CPU.size() + FS.size());
Key += CPU;
Key += FS;
// FIXME: This is related to the code below to reset the target options,
// we need to know whether or not the soft float flag is set on the
// function before we can generate a subtarget. We also need to use
// it as a key for the subtarget since that can be the only difference
// between two functions.
bool SoftFloat =
F.getFnAttribute("use-soft-float").getValueAsString() == "true";
// If the soft float attribute is set on the function turn on the soft float
// subtarget feature.
if (SoftFloat)
Key += FS.empty() ? "+soft-float" : ",+soft-float";
// Keep track of the key width after all features are added so we can extract
// the feature string out later.
unsigned CPUFSWidth = Key.size();
// Extract prefer-vector-width attribute.
unsigned PreferVectorWidthOverride = 0;
if (F.hasFnAttribute("prefer-vector-width")) {
StringRef Val = F.getFnAttribute("prefer-vector-width").getValueAsString();
unsigned Width;
if (!Val.getAsInteger(0, Width)) {
Key += ",prefer-vector-width=";
Key += Val;
PreferVectorWidthOverride = Width;
}
}
// Extract min-legal-vector-width attribute.
unsigned RequiredVectorWidth = UINT32_MAX;
if (F.hasFnAttribute("min-legal-vector-width")) {
StringRef Val =
F.getFnAttribute("min-legal-vector-width").getValueAsString();
unsigned Width;
if (!Val.getAsInteger(0, Width)) {
Key += ",min-legal-vector-width=";
Key += Val;
RequiredVectorWidth = Width;
}
}
// Extracted here so that we make sure there is backing for the StringRef. If
// we assigned earlier, its possible the SmallString reallocated leaving a
// dangling StringRef.
FS = Key.slice(CPU.size(), CPUFSWidth);
auto &I = SubtargetMap[Key];
if (!I) {
// This needs to be done before we create a new subtarget since any
// creation will depend on the TM and the code generation flags on the
// function that reside in TargetOptions.
resetTargetOptions(F);
I = llvm::make_unique<X86Subtarget>(TargetTriple, CPU, FS, *this,
Options.StackAlignmentOverride,
PreferVectorWidthOverride,
RequiredVectorWidth);
}
return I.get();
}
void RecordStreamer::flushSymverDirectives() {
// Mapping from mangled name to GV.
StringMap<const GlobalValue *> MangledNameMap;
// The name in the assembler will be mangled, but the name in the IR
// might not, so we first compute a mapping from mangled name to GV.
Mangler Mang;
SmallString<64> MangledName;
for (const GlobalValue &GV : M.global_values()) {
if (!GV.hasName())
continue;
MangledName.clear();
MangledName.reserve(GV.getName().size() + 1);
Mang.getNameWithPrefix(MangledName, &GV, /*CannotUsePrivateLabel=*/false);
MangledNameMap[MangledName] = &GV;
}
// Walk all the recorded .symver aliases, and set up the binding
// for each alias.
for (auto &Symver : SymverAliasMap) {
const MCSymbol *Aliasee = Symver.first;
MCSymbolAttr Attr = MCSA_Invalid;
bool IsDefined = false;
// First check if the aliasee binding was recorded in the asm.
RecordStreamer::State state = getSymbolState(Aliasee);
switch (state) {
case RecordStreamer::Global:
case RecordStreamer::DefinedGlobal:
Attr = MCSA_Global;
break;
case RecordStreamer::UndefinedWeak:
case RecordStreamer::DefinedWeak:
Attr = MCSA_Weak;
break;
default:
break;
}
switch (state) {
case RecordStreamer::Defined:
case RecordStreamer::DefinedGlobal:
case RecordStreamer::DefinedWeak:
IsDefined = true;
break;
case RecordStreamer::NeverSeen:
case RecordStreamer::Global:
case RecordStreamer::Used:
case RecordStreamer::UndefinedWeak:
break;
}
if (Attr == MCSA_Invalid || !IsDefined) {
const GlobalValue *GV = M.getNamedValue(Aliasee->getName());
if (!GV) {
auto MI = MangledNameMap.find(Aliasee->getName());
if (MI != MangledNameMap.end())
GV = MI->second;
}
if (GV) {
// If we don't have a symbol attribute from assembly, then check if
// the aliasee was defined in the IR.
if (Attr == MCSA_Invalid) {
if (GV->hasExternalLinkage())
Attr = MCSA_Global;
else if (GV->hasLocalLinkage())
Attr = MCSA_Local;
else if (GV->isWeakForLinker())
Attr = MCSA_Weak;
}
IsDefined = IsDefined || !GV->isDeclarationForLinker();
}
}
// Set the detected binding on each alias with this aliasee.
for (auto AliasName : Symver.second) {
std::pair<StringRef, StringRef> Split = AliasName.split("@@@");
SmallString<128> NewName;
if (!Split.second.empty() && !Split.second.startswith("@")) {
// Special processing for "@@@" according
// https://sourceware.org/binutils/docs/as/Symver.html
const char *Separator = IsDefined ? "@@" : "@";
AliasName =
(Split.first + Separator + Split.second).toStringRef(NewName);
}
MCSymbol *Alias = getContext().getOrCreateSymbol(AliasName);
// TODO: Handle "@@@". Depending on SymbolAttribute value it needs to be
// converted into @ or @@.
const MCExpr *Value = MCSymbolRefExpr::create(Aliasee, getContext());
if (IsDefined)
markDefined(*Alias);
// Don't use EmitAssignment override as it always marks alias as defined.
MCStreamer::EmitAssignment(Alias, Value);
if (Attr != MCSA_Invalid)
EmitSymbolAttribute(Alias, Attr);
}
}
}
// Ensure ELF .symver aliases get the same binding as the defined symbol
// they alias with.
static void handleSymverAliases(const Module &M, RecordStreamer &Streamer) {
if (Streamer.symverAliases().empty())
return;
// The name in the assembler will be mangled, but the name in the IR
// might not, so we first compute a mapping from mangled name to GV.
Mangler Mang;
SmallString<64> MangledName;
StringMap<const GlobalValue *> MangledNameMap;
auto GetMangledName = [&](const GlobalValue &GV) {
if (!GV.hasName())
return;
MangledName.clear();
MangledName.reserve(GV.getName().size() + 1);
Mang.getNameWithPrefix(MangledName, &GV, /*CannotUsePrivateLabel=*/false);
MangledNameMap[MangledName] = &GV;
};
for (const Function &F : M)
GetMangledName(F);
for (const GlobalVariable &GV : M.globals())
GetMangledName(GV);
for (const GlobalAlias &GA : M.aliases())
GetMangledName(GA);
// Walk all the recorded .symver aliases, and set up the binding
// for each alias.
for (auto &Symver : Streamer.symverAliases()) {
const MCSymbol *Aliasee = Symver.first;
MCSymbolAttr Attr = MCSA_Invalid;
// First check if the aliasee binding was recorded in the asm.
RecordStreamer::State state = Streamer.getSymbolState(Aliasee);
switch (state) {
case RecordStreamer::Global:
case RecordStreamer::DefinedGlobal:
Attr = MCSA_Global;
break;
case RecordStreamer::UndefinedWeak:
case RecordStreamer::DefinedWeak:
Attr = MCSA_Weak;
break;
default:
break;
}
// If we don't have a symbol attribute from assembly, then check if
// the aliasee was defined in the IR.
if (Attr == MCSA_Invalid) {
const auto *GV = M.getNamedValue(Aliasee->getName());
if (!GV) {
auto MI = MangledNameMap.find(Aliasee->getName());
if (MI != MangledNameMap.end())
GV = MI->second;
else
continue;
}
if (GV->hasExternalLinkage())
Attr = MCSA_Global;
else if (GV->hasLocalLinkage())
Attr = MCSA_Local;
else if (GV->isWeakForLinker())
Attr = MCSA_Weak;
}
if (Attr == MCSA_Invalid)
continue;
// Set the detected binding on each alias with this aliasee.
for (auto &Alias : Symver.second)
Streamer.EmitSymbolAttribute(Alias, Attr);
}
}
