llvm-6502/lib/IR/Globals.cpp
2014-10-24 22:50:48 +00:00

318 lines
11 KiB
C++

//===-- Globals.cpp - Implement the GlobalValue & GlobalVariable class ----===//
//
// 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 GlobalValue & GlobalVariable classes for the IR
// library.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/GlobalValue.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/LeakDetector.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
#include "llvm/Support/ErrorHandling.h"
using namespace llvm;
//===----------------------------------------------------------------------===//
// GlobalValue Class
//===----------------------------------------------------------------------===//
bool GlobalValue::isMaterializable() const {
if (const Function *F = dyn_cast<Function>(this))
return F->isMaterializable();
return false;
}
bool GlobalValue::isDematerializable() const {
return getParent() && getParent()->isDematerializable(this);
}
std::error_code GlobalValue::materialize() {
return getParent()->materialize(this);
}
void GlobalValue::Dematerialize() {
getParent()->Dematerialize(this);
}
const DataLayout *GlobalValue::getDataLayout() const {
return getParent()->getDataLayout();
}
/// Override destroyConstant to make sure it doesn't get called on
/// GlobalValue's because they shouldn't be treated like other constants.
void GlobalValue::destroyConstant() {
llvm_unreachable("You can't GV->destroyConstant()!");
}
/// copyAttributesFrom - copy all additional attributes (those not needed to
/// create a GlobalValue) from the GlobalValue Src to this one.
void GlobalValue::copyAttributesFrom(const GlobalValue *Src) {
setVisibility(Src->getVisibility());
setUnnamedAddr(Src->hasUnnamedAddr());
setDLLStorageClass(Src->getDLLStorageClass());
}
unsigned GlobalValue::getAlignment() const {
if (auto *GA = dyn_cast<GlobalAlias>(this)) {
// In general we cannot compute this at the IR level, but we try.
if (const GlobalObject *GO = GA->getBaseObject())
return GO->getAlignment();
// FIXME: we should also be able to handle:
// Alias = Global + Offset
// Alias = Absolute
return 0;
}
return cast<GlobalObject>(this)->getAlignment();
}
void GlobalObject::setAlignment(unsigned Align) {
assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
assert(Align <= MaximumAlignment &&
"Alignment is greater than MaximumAlignment!");
unsigned AlignmentData = Log2_32(Align) + 1;
unsigned OldData = getGlobalValueSubClassData();
setGlobalValueSubClassData((OldData & ~AlignmentMask) | AlignmentData);
assert(getAlignment() == Align && "Alignment representation error!");
}
unsigned GlobalObject::getGlobalObjectSubClassData() const {
unsigned ValueData = getGlobalValueSubClassData();
return ValueData >> AlignmentBits;
}
void GlobalObject::setGlobalObjectSubClassData(unsigned Val) {
unsigned OldData = getGlobalValueSubClassData();
setGlobalValueSubClassData((OldData & AlignmentMask) |
(Val << AlignmentBits));
assert(getGlobalObjectSubClassData() == Val && "representation error");
}
void GlobalObject::copyAttributesFrom(const GlobalValue *Src) {
const auto *GV = cast<GlobalObject>(Src);
GlobalValue::copyAttributesFrom(GV);
setAlignment(GV->getAlignment());
setSection(GV->getSection());
}
const char *GlobalValue::getSection() const {
if (auto *GA = dyn_cast<GlobalAlias>(this)) {
// In general we cannot compute this at the IR level, but we try.
if (const GlobalObject *GO = GA->getBaseObject())
return GO->getSection();
return "";
}
return cast<GlobalObject>(this)->getSection();
}
Comdat *GlobalValue::getComdat() {
if (auto *GA = dyn_cast<GlobalAlias>(this)) {
// In general we cannot compute this at the IR level, but we try.
if (const GlobalObject *GO = GA->getBaseObject())
return const_cast<GlobalObject *>(GO)->getComdat();
return nullptr;
}
return cast<GlobalObject>(this)->getComdat();
}
void GlobalObject::setSection(StringRef S) { Section = S; }
bool GlobalValue::isDeclaration() const {
// Globals are definitions if they have an initializer.
if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(this))
return GV->getNumOperands() == 0;
// Functions are definitions if they have a body.
if (const Function *F = dyn_cast<Function>(this))
return F->empty() && !F->isMaterializable();
// Aliases are always definitions.
assert(isa<GlobalAlias>(this));
return false;
}
//===----------------------------------------------------------------------===//
// GlobalVariable Implementation
//===----------------------------------------------------------------------===//
GlobalVariable::GlobalVariable(Type *Ty, bool constant, LinkageTypes Link,
Constant *InitVal, const Twine &Name,
ThreadLocalMode TLMode, unsigned AddressSpace,
bool isExternallyInitialized)
: GlobalObject(PointerType::get(Ty, AddressSpace), Value::GlobalVariableVal,
OperandTraits<GlobalVariable>::op_begin(this),
InitVal != nullptr, Link, Name),
isConstantGlobal(constant),
isExternallyInitializedConstant(isExternallyInitialized) {
setThreadLocalMode(TLMode);
if (InitVal) {
assert(InitVal->getType() == Ty &&
"Initializer should be the same type as the GlobalVariable!");
Op<0>() = InitVal;
}
LeakDetector::addGarbageObject(this);
}
GlobalVariable::GlobalVariable(Module &M, Type *Ty, bool constant,
LinkageTypes Link, Constant *InitVal,
const Twine &Name, GlobalVariable *Before,
ThreadLocalMode TLMode, unsigned AddressSpace,
bool isExternallyInitialized)
: GlobalObject(PointerType::get(Ty, AddressSpace), Value::GlobalVariableVal,
OperandTraits<GlobalVariable>::op_begin(this),
InitVal != nullptr, Link, Name),
isConstantGlobal(constant),
isExternallyInitializedConstant(isExternallyInitialized) {
setThreadLocalMode(TLMode);
if (InitVal) {
assert(InitVal->getType() == Ty &&
"Initializer should be the same type as the GlobalVariable!");
Op<0>() = InitVal;
}
LeakDetector::addGarbageObject(this);
if (Before)
Before->getParent()->getGlobalList().insert(Before, this);
else
M.getGlobalList().push_back(this);
}
void GlobalVariable::setParent(Module *parent) {
if (getParent())
LeakDetector::addGarbageObject(this);
Parent = parent;
if (getParent())
LeakDetector::removeGarbageObject(this);
}
void GlobalVariable::removeFromParent() {
getParent()->getGlobalList().remove(this);
}
void GlobalVariable::eraseFromParent() {
getParent()->getGlobalList().erase(this);
}
void GlobalVariable::replaceUsesOfWithOnConstant(Value *From, Value *To,
Use *U) {
// If you call this, then you better know this GVar has a constant
// initializer worth replacing. Enforce that here.
assert(getNumOperands() == 1 &&
"Attempt to replace uses of Constants on a GVar with no initializer");
// And, since you know it has an initializer, the From value better be
// the initializer :)
assert(getOperand(0) == From &&
"Attempt to replace wrong constant initializer in GVar");
// And, you better have a constant for the replacement value
assert(isa<Constant>(To) &&
"Attempt to replace GVar initializer with non-constant");
// Okay, preconditions out of the way, replace the constant initializer.
this->setOperand(0, cast<Constant>(To));
}
void GlobalVariable::setInitializer(Constant *InitVal) {
if (!InitVal) {
if (hasInitializer()) {
Op<0>().set(nullptr);
NumOperands = 0;
}
} else {
assert(InitVal->getType() == getType()->getElementType() &&
"Initializer type must match GlobalVariable type");
if (!hasInitializer())
NumOperands = 1;
Op<0>().set(InitVal);
}
}
/// copyAttributesFrom - copy all additional attributes (those not needed to
/// create a GlobalVariable) from the GlobalVariable Src to this one.
void GlobalVariable::copyAttributesFrom(const GlobalValue *Src) {
assert(isa<GlobalVariable>(Src) && "Expected a GlobalVariable!");
GlobalObject::copyAttributesFrom(Src);
const GlobalVariable *SrcVar = cast<GlobalVariable>(Src);
setThreadLocalMode(SrcVar->getThreadLocalMode());
}
//===----------------------------------------------------------------------===//
// GlobalAlias Implementation
//===----------------------------------------------------------------------===//
GlobalAlias::GlobalAlias(Type *Ty, unsigned AddressSpace, LinkageTypes Link,
const Twine &Name, Constant *Aliasee,
Module *ParentModule)
: GlobalValue(PointerType::get(Ty, AddressSpace), Value::GlobalAliasVal,
&Op<0>(), 1, Link, Name) {
LeakDetector::addGarbageObject(this);
Op<0>() = Aliasee;
if (ParentModule)
ParentModule->getAliasList().push_back(this);
}
GlobalAlias *GlobalAlias::create(Type *Ty, unsigned AddressSpace,
LinkageTypes Link, const Twine &Name,
Constant *Aliasee, Module *ParentModule) {
return new GlobalAlias(Ty, AddressSpace, Link, Name, Aliasee, ParentModule);
}
GlobalAlias *GlobalAlias::create(Type *Ty, unsigned AddressSpace,
LinkageTypes Linkage, const Twine &Name,
Module *Parent) {
return create(Ty, AddressSpace, Linkage, Name, nullptr, Parent);
}
GlobalAlias *GlobalAlias::create(Type *Ty, unsigned AddressSpace,
LinkageTypes Linkage, const Twine &Name,
GlobalValue *Aliasee) {
return create(Ty, AddressSpace, Linkage, Name, Aliasee, Aliasee->getParent());
}
GlobalAlias *GlobalAlias::create(LinkageTypes Link, const Twine &Name,
GlobalValue *Aliasee) {
PointerType *PTy = Aliasee->getType();
return create(PTy->getElementType(), PTy->getAddressSpace(), Link, Name,
Aliasee);
}
GlobalAlias *GlobalAlias::create(const Twine &Name, GlobalValue *Aliasee) {
return create(Aliasee->getLinkage(), Name, Aliasee);
}
void GlobalAlias::setParent(Module *parent) {
if (getParent())
LeakDetector::addGarbageObject(this);
Parent = parent;
if (getParent())
LeakDetector::removeGarbageObject(this);
}
void GlobalAlias::removeFromParent() {
getParent()->getAliasList().remove(this);
}
void GlobalAlias::eraseFromParent() {
getParent()->getAliasList().erase(this);
}
void GlobalAlias::setAliasee(Constant *Aliasee) {
assert((!Aliasee || Aliasee->getType() == getType()) &&
"Alias and aliasee types should match!");
setOperand(0, Aliasee);
}