void TargetLoweringObjectFileCOFF::emitModuleFlags(
MCStreamer &Streamer, ArrayRef<Module::ModuleFlagEntry> ModuleFlags,
const TargetMachine &TM) const {
MDNode *LinkerOptions = nullptr;
for (const auto &MFE : ModuleFlags) {
StringRef Key = MFE.Key->getString();
if (Key == "Linker Options")
LinkerOptions = cast<MDNode>(MFE.Val);
}
if (LinkerOptions) {
// Emit the linker options to the linker .drectve section. According to the
// spec, this section is a space-separated string containing flags for
// linker.
MCSection *Sec = getDrectveSection();
Streamer.SwitchSection(Sec);
for (const auto &Option : LinkerOptions->operands()) {
for (const auto &Piece : cast<MDNode>(Option)->operands()) {
// Lead with a space for consistency with our dllexport implementation.
std::string Directive(" ");
Directive.append(cast<MDString>(Piece)->getString());
Streamer.EmitBytes(Directive);
}
}
}
}
/// \brief Map a distinct MDNode.
///
/// Distinct nodes are not uniqued, so they must always recreated.
static Metadata *mapDistinctNode(const MDNode *Node,
SmallVectorImpl<MDNode *> &Cycles,
ValueToValueMapTy &VM, RemapFlags Flags,
ValueMapTypeRemapper *TypeMapper,
ValueMaterializer *Materializer) {
assert(Node->isDistinct() && "Expected distinct node");
MDNode *NewMD = MDNode::replaceWithDistinct(Node->clone());
remap(Node, NewMD, Cycles, VM, Flags, TypeMapper, Materializer);
// Track any cycles beneath this node.
for (Metadata *Op : NewMD->operands())
if (auto *Node = dyn_cast_or_null<MDNode>(Op))
if (!Node->isResolved())
Cycles.push_back(Node);
return NewMD;
}
bool Loop::isAnnotatedParallel() const {
MDNode *DesiredLoopIdMetadata = getLoopID();
if (!DesiredLoopIdMetadata)
return false;
// The loop branch contains the parallel loop metadata. In order to ensure
// that any parallel-loop-unaware optimization pass hasn't added loop-carried
// dependencies (thus converted the loop back to a sequential loop), check
// that all the memory instructions in the loop contain parallelism metadata
// that point to the same unique "loop id metadata" the loop branch does.
for (BasicBlock *BB : this->blocks()) {
for (Instruction &I : *BB) {
if (!I.mayReadOrWriteMemory())
continue;
// The memory instruction can refer to the loop identifier metadata
// directly or indirectly through another list metadata (in case of
// nested parallel loops). The loop identifier metadata refers to
// itself so we can check both cases with the same routine.
MDNode *LoopIdMD =
I.getMetadata(LLVMContext::MD_mem_parallel_loop_access);
if (!LoopIdMD)
return false;
bool LoopIdMDFound = false;
for (const MDOperand &MDOp : LoopIdMD->operands()) {
if (MDOp == DesiredLoopIdMetadata) {
LoopIdMDFound = true;
break;
}
}
if (!LoopIdMDFound)
return false;
}
}
return true;
}
Optional<MDNode *> llvm::makeFollowupLoopID(
MDNode *OrigLoopID, ArrayRef<StringRef> FollowupOptions,
const char *InheritOptionsExceptPrefix, bool AlwaysNew) {
if (!OrigLoopID) {
if (AlwaysNew)
return nullptr;
return None;
}
assert(OrigLoopID->getOperand(0) == OrigLoopID);
bool InheritAllAttrs = !InheritOptionsExceptPrefix;
bool InheritSomeAttrs =
InheritOptionsExceptPrefix && InheritOptionsExceptPrefix[0] != '\0';
SmallVector<Metadata *, 8> MDs;
MDs.push_back(nullptr);
bool Changed = false;
if (InheritAllAttrs || InheritSomeAttrs) {
for (const MDOperand &Existing : drop_begin(OrigLoopID->operands(), 1)) {
MDNode *Op = cast<MDNode>(Existing.get());
auto InheritThisAttribute = [InheritSomeAttrs,
InheritOptionsExceptPrefix](MDNode *Op) {
if (!InheritSomeAttrs)
return false;
// Skip malformatted attribute metadata nodes.
if (Op->getNumOperands() == 0)
return true;
Metadata *NameMD = Op->getOperand(0).get();
if (!isa<MDString>(NameMD))
return true;
StringRef AttrName = cast<MDString>(NameMD)->getString();
// Do not inherit excluded attributes.
return !AttrName.startswith(InheritOptionsExceptPrefix);
};
if (InheritThisAttribute(Op))
MDs.push_back(Op);
else
Changed = true;
}
} else {
// Modified if we dropped at least one attribute.
Changed = OrigLoopID->getNumOperands() > 1;
}
bool HasAnyFollowup = false;
for (StringRef OptionName : FollowupOptions) {
MDNode *FollowupNode = findOptionMDForLoopID(OrigLoopID, OptionName);
if (!FollowupNode)
continue;
HasAnyFollowup = true;
for (const MDOperand &Option : drop_begin(FollowupNode->operands(), 1)) {
MDs.push_back(Option.get());
Changed = true;
}
}
// Attributes of the followup loop not specified explicity, so signal to the
// transformation pass to add suitable attributes.
if (!AlwaysNew && !HasAnyFollowup)
return None;
// If no attributes were added or remove, the previous loop Id can be reused.
if (!AlwaysNew && !Changed)
return OrigLoopID;
// No attributes is equivalent to having no !llvm.loop metadata at all.
if (MDs.size() == 1)
return nullptr;
// Build the new loop ID.
MDTuple *FollowupLoopID = MDNode::get(OrigLoopID->getContext(), MDs);
FollowupLoopID->replaceOperandWith(0, FollowupLoopID);
return FollowupLoopID;
}
bool Loop::isAnnotatedParallel() const {
MDNode *DesiredLoopIdMetadata = getLoopID();
if (!DesiredLoopIdMetadata)
return false;
MDNode *ParallelAccesses =
findOptionMDForLoop(this, "llvm.loop.parallel_accesses");
SmallPtrSet<MDNode *, 4>
ParallelAccessGroups; // For scalable 'contains' check.
if (ParallelAccesses) {
for (const MDOperand &MD : drop_begin(ParallelAccesses->operands(), 1)) {
MDNode *AccGroup = cast<MDNode>(MD.get());
assert(isValidAsAccessGroup(AccGroup) &&
"List item must be an access group");
ParallelAccessGroups.insert(AccGroup);
}
}
// The loop branch contains the parallel loop metadata. In order to ensure
// that any parallel-loop-unaware optimization pass hasn't added loop-carried
// dependencies (thus converted the loop back to a sequential loop), check
// that all the memory instructions in the loop belong to an access group that
// is parallel to this loop.
for (BasicBlock *BB : this->blocks()) {
for (Instruction &I : *BB) {
if (!I.mayReadOrWriteMemory())
continue;
if (MDNode *AccessGroup = I.getMetadata(LLVMContext::MD_access_group)) {
auto ContainsAccessGroup = [&ParallelAccessGroups](MDNode *AG) -> bool {
if (AG->getNumOperands() == 0) {
assert(isValidAsAccessGroup(AG) && "Item must be an access group");
return ParallelAccessGroups.count(AG);
}
for (const MDOperand &AccessListItem : AG->operands()) {
MDNode *AccGroup = cast<MDNode>(AccessListItem.get());
assert(isValidAsAccessGroup(AccGroup) &&
"List item must be an access group");
if (ParallelAccessGroups.count(AccGroup))
return true;
}
return false;
};
if (ContainsAccessGroup(AccessGroup))
continue;
}
// The memory instruction can refer to the loop identifier metadata
// directly or indirectly through another list metadata (in case of
// nested parallel loops). The loop identifier metadata refers to
// itself so we can check both cases with the same routine.
MDNode *LoopIdMD =
I.getMetadata(LLVMContext::MD_mem_parallel_loop_access);
if (!LoopIdMD)
return false;
bool LoopIdMDFound = false;
for (const MDOperand &MDOp : LoopIdMD->operands()) {
if (MDOp == DesiredLoopIdMetadata) {
LoopIdMDFound = true;
break;
}
}
if (!LoopIdMDFound)
return false;
}
}
return true;
}
/// emitModuleFlags - Perform code emission for module flags.
void TargetLoweringObjectFileMachO::emitModuleFlags(
MCStreamer &Streamer, ArrayRef<Module::ModuleFlagEntry> ModuleFlags,
const TargetMachine &TM) const {
unsigned VersionVal = 0;
unsigned ImageInfoFlags = 0;
MDNode *LinkerOptions = nullptr;
StringRef SectionVal;
for (const auto &MFE : ModuleFlags) {
// Ignore flags with 'Require' behavior.
if (MFE.Behavior == Module::Require)
continue;
StringRef Key = MFE.Key->getString();
Metadata *Val = MFE.Val;
if (Key == "Objective-C Image Info Version") {
VersionVal = mdconst::extract<ConstantInt>(Val)->getZExtValue();
} else if (Key == "Objective-C Garbage Collection" ||
Key == "Objective-C GC Only" ||
Key == "Objective-C Is Simulated" ||
Key == "Objective-C Class Properties" ||
Key == "Objective-C Image Swift Version") {
ImageInfoFlags |= mdconst::extract<ConstantInt>(Val)->getZExtValue();
} else if (Key == "Objective-C Image Info Section") {
SectionVal = cast<MDString>(Val)->getString();
} else if (Key == "Linker Options") {
LinkerOptions = cast<MDNode>(Val);
}
}
// Emit the linker options if present.
if (LinkerOptions) {
for (const auto &Option : LinkerOptions->operands()) {
SmallVector<std::string, 4> StrOptions;
for (const auto &Piece : cast<MDNode>(Option)->operands())
StrOptions.push_back(cast<MDString>(Piece)->getString());
Streamer.EmitLinkerOptions(StrOptions);
}
}
// The section is mandatory. If we don't have it, then we don't have GC info.
if (SectionVal.empty()) return;
StringRef Segment, Section;
unsigned TAA = 0, StubSize = 0;
bool TAAParsed;
std::string ErrorCode =
MCSectionMachO::ParseSectionSpecifier(SectionVal, Segment, Section,
TAA, TAAParsed, StubSize);
if (!ErrorCode.empty())
// If invalid, report the error with report_fatal_error.
report_fatal_error("Invalid section specifier '" + Section + "': " +
ErrorCode + ".");
// Get the section.
MCSectionMachO *S = getContext().getMachOSection(
Segment, Section, TAA, StubSize, SectionKind::getData());
Streamer.SwitchSection(S);
Streamer.EmitLabel(getContext().
getOrCreateSymbol(StringRef("L_OBJC_IMAGE_INFO")));
Streamer.EmitIntValue(VersionVal, 4);
Streamer.EmitIntValue(ImageInfoFlags, 4);
Streamer.AddBlankLine();
}
