llvm-6502/lib/VMCore/Function.cpp
Duncan Sands 92432a8db1 Convenience method for setting the nounwind
attribute for a function.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49373 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-08 07:23:58 +00:00

374 lines
12 KiB
C++

//===-- Function.cpp - Implement the Global object classes ----------------===//
//
// 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 Function class for the VMCore library.
//
//===----------------------------------------------------------------------===//
#include "llvm/Module.h"
#include "llvm/DerivedTypes.h"
#include "llvm/IntrinsicInst.h"
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/Support/LeakDetector.h"
#include "llvm/Support/StringPool.h"
#include "SymbolTableListTraitsImpl.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/StringExtras.h"
using namespace llvm;
BasicBlock *ilist_traits<BasicBlock>::createSentinel() {
BasicBlock *Ret = BasicBlock::Create();
// This should not be garbage monitored.
LeakDetector::removeGarbageObject(Ret);
return Ret;
}
iplist<BasicBlock> &ilist_traits<BasicBlock>::getList(Function *F) {
return F->getBasicBlockList();
}
Argument *ilist_traits<Argument>::createSentinel() {
Argument *Ret = new Argument(Type::Int32Ty);
// This should not be garbage monitored.
LeakDetector::removeGarbageObject(Ret);
return Ret;
}
iplist<Argument> &ilist_traits<Argument>::getList(Function *F) {
return F->getArgumentList();
}
// Explicit instantiations of SymbolTableListTraits since some of the methods
// are not in the public header file...
template class SymbolTableListTraits<Argument, Function>;
template class SymbolTableListTraits<BasicBlock, Function>;
//===----------------------------------------------------------------------===//
// Argument Implementation
//===----------------------------------------------------------------------===//
Argument::Argument(const Type *Ty, const std::string &Name, Function *Par)
: Value(Ty, Value::ArgumentVal) {
Parent = 0;
// Make sure that we get added to a function
LeakDetector::addGarbageObject(this);
if (Par)
Par->getArgumentList().push_back(this);
setName(Name);
}
void Argument::setParent(Function *parent) {
if (getParent())
LeakDetector::addGarbageObject(this);
Parent = parent;
if (getParent())
LeakDetector::removeGarbageObject(this);
}
/// getArgNo - Return the index of this formal argument in its containing
/// function. For example in "void foo(int a, float b)" a is 0 and b is 1.
unsigned Argument::getArgNo() const {
const Function *F = getParent();
assert(F && "Argument is not in a function");
Function::const_arg_iterator AI = F->arg_begin();
unsigned ArgIdx = 0;
for (; &*AI != this; ++AI)
++ArgIdx;
return ArgIdx;
}
/// hasByValAttr - Return true if this argument has the byval attribute on it
/// in its containing function.
bool Argument::hasByValAttr() const {
if (!isa<PointerType>(getType())) return false;
return getParent()->paramHasAttr(getArgNo()+1, ParamAttr::ByVal);
}
/// hasNoAliasAttr - Return true if this argument has the noalias attribute on
/// it in its containing function.
bool Argument::hasNoAliasAttr() const {
if (!isa<PointerType>(getType())) return false;
return getParent()->paramHasAttr(getArgNo()+1, ParamAttr::NoAlias);
}
/// hasSRetAttr - Return true if this argument has the sret attribute on
/// it in its containing function.
bool Argument::hasStructRetAttr() const {
if (!isa<PointerType>(getType())) return false;
if (this != getParent()->arg_begin()) return false; // StructRet param must be first param
return getParent()->paramHasAttr(1, ParamAttr::StructRet);
}
//===----------------------------------------------------------------------===//
// Helper Methods in Function
//===----------------------------------------------------------------------===//
const FunctionType *Function::getFunctionType() const {
return cast<FunctionType>(getType()->getElementType());
}
bool Function::isVarArg() const {
return getFunctionType()->isVarArg();
}
const Type *Function::getReturnType() const {
return getFunctionType()->getReturnType();
}
void Function::removeFromParent() {
getParent()->getFunctionList().remove(this);
}
void Function::eraseFromParent() {
getParent()->getFunctionList().erase(this);
}
//===----------------------------------------------------------------------===//
// Function Implementation
//===----------------------------------------------------------------------===//
Function::Function(const FunctionType *Ty, LinkageTypes Linkage,
const std::string &name, Module *ParentModule)
: GlobalValue(PointerType::getUnqual(Ty),
Value::FunctionVal, 0, 0, Linkage, name) {
SymTab = new ValueSymbolTable();
assert((getReturnType()->isFirstClassType() ||getReturnType() == Type::VoidTy
|| isa<StructType>(getReturnType()))
&& "LLVM functions cannot return aggregate values!");
// If the function has arguments, mark them as lazily built.
if (Ty->getNumParams())
SubclassData = 1; // Set the "has lazy arguments" bit.
// Make sure that we get added to a function
LeakDetector::addGarbageObject(this);
if (ParentModule)
ParentModule->getFunctionList().push_back(this);
// Ensure intrinsics have the right parameter attributes.
if (unsigned IID = getIntrinsicID(true))
setParamAttrs(Intrinsic::getParamAttrs(Intrinsic::ID(IID)));
}
Function::~Function() {
dropAllReferences(); // After this it is safe to delete instructions.
// Delete all of the method arguments and unlink from symbol table...
ArgumentList.clear();
delete SymTab;
// Remove the function from the on-the-side collector table.
clearCollector();
}
void Function::BuildLazyArguments() const {
// Create the arguments vector, all arguments start out unnamed.
const FunctionType *FT = getFunctionType();
for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
assert(FT->getParamType(i) != Type::VoidTy &&
"Cannot have void typed arguments!");
ArgumentList.push_back(new Argument(FT->getParamType(i)));
}
// Clear the lazy arguments bit.
const_cast<Function*>(this)->SubclassData &= ~1;
}
size_t Function::arg_size() const {
return getFunctionType()->getNumParams();
}
bool Function::arg_empty() const {
return getFunctionType()->getNumParams() == 0;
}
void Function::setParent(Module *parent) {
if (getParent())
LeakDetector::addGarbageObject(this);
Parent = parent;
if (getParent())
LeakDetector::removeGarbageObject(this);
}
// dropAllReferences() - This function causes all the subinstructions to "let
// go" of all references that they are maintaining. This allows one to
// 'delete' a whole class at a time, even though there may be circular
// references... first all references are dropped, and all use counts go to
// zero. Then everything is deleted for real. Note that no operations are
// valid on an object that has "dropped all references", except operator
// delete.
//
void Function::dropAllReferences() {
for (iterator I = begin(), E = end(); I != E; ++I)
I->dropAllReferences();
BasicBlocks.clear(); // Delete all basic blocks...
}
void Function::setDoesNotThrow(bool doesNotThrow) {
PAListPtr PAL = getParamAttrs();
if (doesNotThrow)
PAL = PAL.addAttr(0, ParamAttr::NoUnwind);
else
PAL = PAL.removeAttr(0, ParamAttr::NoUnwind);
setParamAttrs(PAL);
}
// Maintain the collector name for each function in an on-the-side table. This
// saves allocating an additional word in Function for programs which do not use
// GC (i.e., most programs) at the cost of increased overhead for clients which
// do use GC.
static DenseMap<const Function*,PooledStringPtr> *CollectorNames;
static StringPool *CollectorNamePool;
bool Function::hasCollector() const {
return CollectorNames && CollectorNames->count(this);
}
const char *Function::getCollector() const {
assert(hasCollector() && "Function has no collector");
return *(*CollectorNames)[this];
}
void Function::setCollector(const char *Str) {
if (!CollectorNamePool)
CollectorNamePool = new StringPool();
if (!CollectorNames)
CollectorNames = new DenseMap<const Function*,PooledStringPtr>();
(*CollectorNames)[this] = CollectorNamePool->intern(Str);
}
void Function::clearCollector() {
if (CollectorNames) {
CollectorNames->erase(this);
if (CollectorNames->empty()) {
delete CollectorNames;
CollectorNames = 0;
if (CollectorNamePool->empty()) {
delete CollectorNamePool;
CollectorNamePool = 0;
}
}
}
}
/// getIntrinsicID - This method returns the ID number of the specified
/// function, or Intrinsic::not_intrinsic if the function is not an
/// intrinsic, or if the pointer is null. This value is always defined to be
/// zero to allow easy checking for whether a function is intrinsic or not. The
/// particular intrinsic functions which correspond to this value are defined in
/// llvm/Intrinsics.h.
///
unsigned Function::getIntrinsicID(bool noAssert) const {
const ValueName *ValName = this->getValueName();
if (!ValName)
return 0;
unsigned Len = ValName->getKeyLength();
const char *Name = ValName->getKeyData();
if (Len < 5 || Name[4] != '.' || Name[0] != 'l' || Name[1] != 'l'
|| Name[2] != 'v' || Name[3] != 'm')
return 0; // All intrinsics start with 'llvm.'
assert((Len != 5 || noAssert) && "'llvm.' is an invalid intrinsic name!");
#define GET_FUNCTION_RECOGNIZER
#include "llvm/Intrinsics.gen"
#undef GET_FUNCTION_RECOGNIZER
assert(noAssert && "Invalid LLVM intrinsic name");
return 0;
}
std::string Intrinsic::getName(ID id, const Type **Tys, unsigned numTys) {
assert(id < num_intrinsics && "Invalid intrinsic ID!");
const char * const Table[] = {
"not_intrinsic",
#define GET_INTRINSIC_NAME_TABLE
#include "llvm/Intrinsics.gen"
#undef GET_INTRINSIC_NAME_TABLE
};
if (numTys == 0)
return Table[id];
std::string Result(Table[id]);
for (unsigned i = 0; i < numTys; ++i)
if (Tys[i])
Result += "." + MVT::getValueTypeString(MVT::getValueType(Tys[i]));
return Result;
}
const FunctionType *Intrinsic::getType(ID id, const Type **Tys,
unsigned numTys) {
const Type *ResultTy = NULL;
std::vector<const Type*> ArgTys;
bool IsVarArg = false;
#define GET_INTRINSIC_GENERATOR
#include "llvm/Intrinsics.gen"
#undef GET_INTRINSIC_GENERATOR
return FunctionType::get(ResultTy, ArgTys, IsVarArg);
}
PAListPtr Intrinsic::getParamAttrs(ID id) {
ParameterAttributes Attr = ParamAttr::None;
#define GET_INTRINSIC_ATTRIBUTES
#include "llvm/Intrinsics.gen"
#undef GET_INTRINSIC_ATTRIBUTES
// Intrinsics cannot throw exceptions.
Attr |= ParamAttr::NoUnwind;
ParamAttrsWithIndex PAWI = ParamAttrsWithIndex::get(0, Attr);
return PAListPtr::get(&PAWI, 1);
}
Function *Intrinsic::getDeclaration(Module *M, ID id, const Type **Tys,
unsigned numTys) {
// There can never be multiple globals with the same name of different types,
// because intrinsics must be a specific type.
return
cast<Function>(M->getOrInsertFunction(getName(id, Tys, numTys),
getType(id, Tys, numTys)));
}
Value *IntrinsicInst::StripPointerCasts(Value *Ptr) {
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Ptr)) {
if (CE->getOpcode() == Instruction::BitCast) {
if (isa<PointerType>(CE->getOperand(0)->getType()))
return StripPointerCasts(CE->getOperand(0));
} else if (CE->getOpcode() == Instruction::GetElementPtr) {
for (unsigned i = 1, e = CE->getNumOperands(); i != e; ++i)
if (!CE->getOperand(i)->isNullValue())
return Ptr;
return StripPointerCasts(CE->getOperand(0));
}
return Ptr;
}
if (BitCastInst *CI = dyn_cast<BitCastInst>(Ptr)) {
if (isa<PointerType>(CI->getOperand(0)->getType()))
return StripPointerCasts(CI->getOperand(0));
} else if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Ptr)) {
if (GEP->hasAllZeroIndices())
return StripPointerCasts(GEP->getOperand(0));
}
return Ptr;
}
// vim: sw=2 ai