Don't create a SymbolTable in Function when the LLVMContext discards value names (NFC)

The ValueSymbolTable is used to detect name conflict and rename
instructions automatically. This is not needed when the value
names are automatically discarded by the LLVMContext.
No functional change intended, just saving a little bit of memory.

This is a recommit of r281806 after fixing the accessor to return
a pointer instead of a reference and updating all the call-sites.

llvm-svn: 281813
This commit is contained in:
Mehdi Amini 2016-09-17 06:00:02 +00:00
parent 05188a646d
commit a53d49e1b5
10 changed files with 29 additions and 25 deletions

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@ -50,7 +50,8 @@ private:
// Important things that make up a function!
BasicBlockListType BasicBlocks; ///< The basic blocks
mutable ArgumentListType ArgumentList; ///< The formal arguments
ValueSymbolTable *SymTab; ///< Symbol table of args/instructions
std::unique_ptr<ValueSymbolTable>
SymTab; ///< Symbol table of args/instructions
AttributeSet AttributeSets; ///< Parameter attributes
/*
@ -493,10 +494,12 @@ public:
//===--------------------------------------------------------------------===//
// Symbol Table Accessing functions...
/// getSymbolTable() - Return the symbol table...
/// getSymbolTable() - Return the symbol table if any, otherwise nullptr.
///
inline ValueSymbolTable &getValueSymbolTable() { return *SymTab; }
inline const ValueSymbolTable &getValueSymbolTable() const { return *SymTab; }
inline ValueSymbolTable *getValueSymbolTable() { return SymTab.get(); }
inline const ValueSymbolTable *getValueSymbolTable() const {
return SymTab.get();
}
//===--------------------------------------------------------------------===//
// BasicBlock iterator forwarding functions

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@ -2504,7 +2504,7 @@ bool LLParser::PerFunctionState::FinishFunction() {
Value *LLParser::PerFunctionState::GetVal(const std::string &Name, Type *Ty,
LocTy Loc) {
// Look this name up in the normal function symbol table.
Value *Val = F.getValueSymbolTable().lookup(Name);
Value *Val = F.getValueSymbolTable()->lookup(Name);
// If this is a forward reference for the value, see if we already created a
// forward ref record.
@ -2922,7 +2922,7 @@ bool LLParser::ParseValID(ValID &ID, PerFunctionState *PFS) {
return Error(Label.Loc, "cannot take address of numeric label after "
"the function is defined");
BB = dyn_cast_or_null<BasicBlock>(
F->getValueSymbolTable().lookup(Label.StrVal));
F->getValueSymbolTable()->lookup(Label.StrVal));
if (!BB)
return Error(Label.Loc, "referenced value is not a basic block");
}
@ -6507,7 +6507,7 @@ bool LLParser::ParseUseListOrderBB() {
return Error(Label.Loc, "invalid numeric label in uselistorder_bb");
if (Label.Kind != ValID::t_LocalName)
return Error(Label.Loc, "expected basic block name in uselistorder_bb");
Value *V = F->getValueSymbolTable().lookup(Label.StrVal);
Value *V = F->getValueSymbolTable()->lookup(Label.StrVal);
if (!V)
return Error(Label.Loc, "invalid basic block in uselistorder_bb");
if (!isa<BasicBlock>(V))

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@ -2999,7 +2999,8 @@ void ModuleBitcodeWriter::writeFunction(
}
// Emit names for all the instructions etc.
writeValueSymbolTable(F.getValueSymbolTable());
if (auto *Symtab = F.getValueSymbolTable())
writeValueSymbolTable(*Symtab);
if (NeedsMetadataAttachment)
writeFunctionMetadataAttachment(F);

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@ -364,7 +364,7 @@ bool MIParser::parseBasicBlockDefinition(
if (!Name.empty()) {
BB = dyn_cast_or_null<BasicBlock>(
MF.getFunction()->getValueSymbolTable().lookup(Name));
MF.getFunction()->getValueSymbolTable()->lookup(Name));
if (!BB)
return error(Loc, Twine("basic block '") + Name +
"' is not defined in the function '" +
@ -1383,7 +1383,7 @@ bool MIParser::parseIRBlock(BasicBlock *&BB, const Function &F) {
switch (Token.kind()) {
case MIToken::NamedIRBlock: {
BB = dyn_cast_or_null<BasicBlock>(
F.getValueSymbolTable().lookup(Token.stringValue()));
F.getValueSymbolTable()->lookup(Token.stringValue()));
if (!BB)
return error(Twine("use of undefined IR block '") + Token.range() + "'");
break;
@ -1729,7 +1729,7 @@ bool MIParser::parseOperandsOffset(MachineOperand &Op) {
bool MIParser::parseIRValue(const Value *&V) {
switch (Token.kind()) {
case MIToken::NamedIRValue: {
V = MF.getFunction()->getValueSymbolTable().lookup(Token.stringValue());
V = MF.getFunction()->getValueSymbolTable()->lookup(Token.stringValue());
break;
}
case MIToken::IRValue: {

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@ -552,7 +552,7 @@ bool MIRParserImpl::initializeFrameInfo(PerFunctionMIParsingState &PFS,
const yaml::StringValue &Name = Object.Name;
if (!Name.Value.empty()) {
Alloca = dyn_cast_or_null<AllocaInst>(
F.getValueSymbolTable().lookup(Name.Value));
F.getValueSymbolTable()->lookup(Name.Value));
if (!Alloca)
return error(Name.SourceRange.Start,
"alloca instruction named '" + Name.Value +

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@ -26,7 +26,7 @@ using namespace llvm;
ValueSymbolTable *BasicBlock::getValueSymbolTable() {
if (Function *F = getParent())
return &F->getValueSymbolTable();
return F->getValueSymbolTable();
return nullptr;
}

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@ -258,7 +258,10 @@ Function::Function(FunctionType *Ty, LinkageTypes Linkage, const Twine &name,
assert(FunctionType::isValidReturnType(getReturnType()) &&
"invalid return type");
setGlobalObjectSubClassData(0);
SymTab = new ValueSymbolTable();
// We only need a symbol table for a function if the context keeps value names
if (!getContext().shouldDiscardValueNames())
SymTab = make_unique<ValueSymbolTable>();
// If the function has arguments, mark them as lazily built.
if (Ty->getNumParams())
@ -279,7 +282,6 @@ Function::~Function() {
// Delete all of the method arguments and unlink from symbol table...
ArgumentList.clear();
delete SymTab;
// Remove the function from the on-the-side GC table.
clearGC();

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@ -143,16 +143,16 @@ static bool getSymTab(Value *V, ValueSymbolTable *&ST) {
if (Instruction *I = dyn_cast<Instruction>(V)) {
if (BasicBlock *P = I->getParent())
if (Function *PP = P->getParent())
ST = &PP->getValueSymbolTable();
ST = PP->getValueSymbolTable();
} else if (BasicBlock *BB = dyn_cast<BasicBlock>(V)) {
if (Function *P = BB->getParent())
ST = &P->getValueSymbolTable();
ST = P->getValueSymbolTable();
} else if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
if (Module *P = GV->getParent())
ST = &P->getValueSymbolTable();
} else if (Argument *A = dyn_cast<Argument>(V)) {
if (Function *P = A->getParent())
ST = &P->getValueSymbolTable();
ST = P->getValueSymbolTable();
} else {
assert(isa<Constant>(V) && "Unknown value type!");
return true; // no name is setable for this.

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@ -219,7 +219,8 @@ static bool StripSymbolNames(Module &M, bool PreserveDbgInfo) {
if (I.hasLocalLinkage() && llvmUsedValues.count(&I) == 0)
if (!PreserveDbgInfo || !I.getName().startswith("llvm.dbg"))
I.setName(""); // Internal symbols can't participate in linkage
StripSymtab(I.getValueSymbolTable(), PreserveDbgInfo);
if (auto *Symtab = I.getValueSymbolTable())
StripSymtab(*Symtab, PreserveDbgInfo);
}
// Remove all names from types.

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@ -461,8 +461,7 @@ bool ReduceCrashingBlocks::TestBlocks(std::vector<const BasicBlock *> &BBs) {
const ValueSymbolTable &GST = M->getValueSymbolTable();
for (unsigned i = 0, e = BlockInfo.size(); i != e; ++i) {
Function *F = cast<Function>(GST.lookup(BlockInfo[i].first));
ValueSymbolTable &ST = F->getValueSymbolTable();
Value *V = ST.lookup(BlockInfo[i].second);
Value *V = F->getValueSymbolTable()->lookup(BlockInfo[i].second);
if (V && V->getType() == Type::getLabelTy(V->getContext()))
BBs.push_back(cast<BasicBlock>(V));
}
@ -572,8 +571,7 @@ bool ReduceCrashingConditionals::TestBlocks(
const ValueSymbolTable &GST = M->getValueSymbolTable();
for (auto &BI : BlockInfo) {
auto *F = cast<Function>(GST.lookup(BI.first));
ValueSymbolTable &ST = F->getValueSymbolTable();
Value *V = ST.lookup(BI.second);
Value *V = F->getValueSymbolTable()->lookup(BI.second);
if (V && V->getType() == Type::getLabelTy(V->getContext()))
BBs.push_back(cast<BasicBlock>(V));
}
@ -666,8 +664,7 @@ bool ReduceSimplifyCFG::TestBlocks(std::vector<const BasicBlock *> &BBs) {
const ValueSymbolTable &GST = M->getValueSymbolTable();
for (auto &BI : BlockInfo) {
auto *F = cast<Function>(GST.lookup(BI.first));
ValueSymbolTable &ST = F->getValueSymbolTable();
Value *V = ST.lookup(BI.second);
Value *V = F->getValueSymbolTable()->lookup(BI.second);
if (V && V->getType() == Type::getLabelTy(V->getContext()))
BBs.push_back(cast<BasicBlock>(V));
}