llvm-project/llvm/lib/CodeGen/PseudoSourceValue.cpp

133 lines
4.0 KiB
C++

//===-- llvm/CodeGen/PseudoSourceValue.cpp ----------------------*- C++ -*-===//
//
// 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 PseudoSourceValue class.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/PseudoSourceValue.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/Mutex.h"
#include "llvm/Support/raw_ostream.h"
#include <map>
using namespace llvm;
namespace {
struct PSVGlobalsTy {
// PseudoSourceValues are immutable so don't need locking.
const PseudoSourceValue PSVs[4];
sys::Mutex Lock; // Guards FSValues, but not the values inside it.
std::map<int, const PseudoSourceValue *> FSValues;
PSVGlobalsTy() : PSVs() {}
~PSVGlobalsTy() {
for (std::map<int, const PseudoSourceValue *>::iterator
I = FSValues.begin(), E = FSValues.end(); I != E; ++I) {
delete I->second;
}
}
};
static ManagedStatic<PSVGlobalsTy> PSVGlobals;
} // anonymous namespace
const PseudoSourceValue *PseudoSourceValue::getStack()
{ return &PSVGlobals->PSVs[0]; }
const PseudoSourceValue *PseudoSourceValue::getGOT()
{ return &PSVGlobals->PSVs[1]; }
const PseudoSourceValue *PseudoSourceValue::getJumpTable()
{ return &PSVGlobals->PSVs[2]; }
const PseudoSourceValue *PseudoSourceValue::getConstantPool()
{ return &PSVGlobals->PSVs[3]; }
static const char *const PSVNames[] = {
"Stack",
"GOT",
"JumpTable",
"ConstantPool"
};
// FIXME: THIS IS A HACK!!!!
// Eventually these should be uniqued on LLVMContext rather than in a managed
// static. For now, we can safely use the global context for the time being to
// squeak by.
PseudoSourceValue::PseudoSourceValue(enum ValueTy Subclass) :
Value(Type::getInt8PtrTy(getGlobalContext()),
Subclass) {}
void PseudoSourceValue::printCustom(raw_ostream &O) const {
O << PSVNames[this - PSVGlobals->PSVs];
}
const PseudoSourceValue *PseudoSourceValue::getFixedStack(int FI) {
PSVGlobalsTy &PG = *PSVGlobals;
sys::ScopedLock locked(PG.Lock);
const PseudoSourceValue *&V = PG.FSValues[FI];
if (!V)
V = new FixedStackPseudoSourceValue(FI);
return V;
}
bool PseudoSourceValue::isConstant(const MachineFrameInfo *) const {
if (this == getStack())
return false;
if (this == getGOT() ||
this == getConstantPool() ||
this == getJumpTable())
return true;
llvm_unreachable("Unknown PseudoSourceValue!");
}
bool PseudoSourceValue::isAliased(const MachineFrameInfo *MFI) const {
if (this == getStack() ||
this == getGOT() ||
this == getConstantPool() ||
this == getJumpTable())
return false;
llvm_unreachable("Unknown PseudoSourceValue!");
}
bool PseudoSourceValue::mayAlias(const MachineFrameInfo *MFI) const {
if (this == getGOT() ||
this == getConstantPool() ||
this == getJumpTable())
return false;
return true;
}
bool FixedStackPseudoSourceValue::isConstant(const MachineFrameInfo *MFI) const{
return MFI && MFI->isImmutableObjectIndex(FI);
}
bool FixedStackPseudoSourceValue::isAliased(const MachineFrameInfo *MFI) const {
// Negative frame indices are used for special things that don't
// appear in LLVM IR. Non-negative indices may be used for things
// like static allocas.
if (!MFI)
return FI >= 0;
// Spill slots should not alias others.
return !MFI->isFixedObjectIndex(FI) && !MFI->isSpillSlotObjectIndex(FI);
}
bool FixedStackPseudoSourceValue::mayAlias(const MachineFrameInfo *MFI) const {
if (!MFI)
return true;
// Spill slots will not alias any LLVM IR value.
return !MFI->isSpillSlotObjectIndex(FI);
}
void FixedStackPseudoSourceValue::printCustom(raw_ostream &OS) const {
OS << "FixedStack" << FI;
}