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

382 lines
12 KiB
C++

//===-- MachineFunction.cpp -----------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Collect native machine code information for a function. This allows
// target-specific information about the generated code to be stored with each
// function.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/SSARegMap.h"
#include "llvm/CodeGen/MachineFunctionInfo.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetFrameInfo.h"
#include "llvm/Function.h"
#include "llvm/iOther.h"
using namespace llvm;
static AnnotationID MF_AID(
AnnotationManager::getID("CodeGen::MachineCodeForFunction"));
namespace {
struct Printer : public MachineFunctionPass {
std::ostream *OS;
const std::string Banner;
Printer (std::ostream *_OS, const std::string &_Banner) :
OS (_OS), Banner (_Banner) { }
const char *getPassName() const { return "MachineFunction Printer"; }
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
}
bool runOnMachineFunction(MachineFunction &MF) {
(*OS) << Banner;
MF.print (*OS);
return false;
}
};
}
/// Returns a newly-created MachineFunction Printer pass. The default output
/// stream is std::cerr; the default banner is empty.
///
FunctionPass *llvm::createMachineFunctionPrinterPass(std::ostream *OS,
const std::string &Banner) {
return new Printer(OS, Banner);
}
namespace {
struct Deleter : public MachineFunctionPass {
const char *getPassName() const { return "Machine Code Deleter"; }
bool runOnMachineFunction(MachineFunction &MF) {
// Delete the annotation from the function now.
MachineFunction::destruct(MF.getFunction());
return true;
}
};
}
/// MachineCodeDeletion Pass - This pass deletes all of the machine code for
/// the current function, which should happen after the function has been
/// emitted to a .s file or to memory.
FunctionPass *llvm::createMachineCodeDeleter() {
return new Deleter();
}
//===---------------------------------------------------------------------===//
// MachineFunction implementation
//===---------------------------------------------------------------------===//
MachineFunction::MachineFunction(const Function *F,
const TargetMachine &TM)
: Annotation(MF_AID), Fn(F), Target(TM), NextMBBNumber(0) {
SSARegMapping = new SSARegMap();
MFInfo = new MachineFunctionInfo(*this);
FrameInfo = new MachineFrameInfo();
ConstantPool = new MachineConstantPool();
}
MachineFunction::~MachineFunction() {
delete SSARegMapping;
delete MFInfo;
delete FrameInfo;
delete ConstantPool;
}
void MachineFunction::dump() const { print(std::cerr); }
void MachineFunction::print(std::ostream &OS) const {
OS << "# Machine code for " << Fn->getName () << "():\n";
// Print Frame Information
getFrameInfo()->print(*this, OS);
// Print Constant Pool
getConstantPool()->print(OS);
for (const_iterator BB = begin(); BB != end(); ++BB)
BB->print(OS);
OS << "\n# End machine code for " << Fn->getName () << "().\n\n";
}
// The next two methods are used to construct and to retrieve
// the MachineCodeForFunction object for the given function.
// construct() -- Allocates and initializes for a given function and target
// get() -- Returns a handle to the object.
// This should not be called before "construct()"
// for a given Function.
//
MachineFunction&
MachineFunction::construct(const Function *Fn, const TargetMachine &Tar)
{
assert(Fn->getAnnotation(MF_AID) == 0 &&
"Object already exists for this function!");
MachineFunction* mcInfo = new MachineFunction(Fn, Tar);
Fn->addAnnotation(mcInfo);
return *mcInfo;
}
void MachineFunction::destruct(const Function *Fn) {
bool Deleted = Fn->deleteAnnotation(MF_AID);
assert(Deleted && "Machine code did not exist for function!");
}
MachineFunction& MachineFunction::get(const Function *F)
{
MachineFunction *mc = (MachineFunction*)F->getAnnotation(MF_AID);
assert(mc && "Call construct() method first to allocate the object");
return *mc;
}
void MachineFunction::clearSSARegMap() {
delete SSARegMapping;
SSARegMapping = 0;
}
//===----------------------------------------------------------------------===//
// MachineFrameInfo implementation
//===----------------------------------------------------------------------===//
/// CreateStackObject - Create a stack object for a value of the specified type.
///
int MachineFrameInfo::CreateStackObject(const Type *Ty, const TargetData &TD) {
return CreateStackObject(TD.getTypeSize(Ty), TD.getTypeAlignment(Ty));
}
int MachineFrameInfo::CreateStackObject(const TargetRegisterClass *RC) {
return CreateStackObject(RC->getSize(), RC->getAlignment());
}
void MachineFrameInfo::print(const MachineFunction &MF, std::ostream &OS) const{
int ValOffset = MF.getTarget().getFrameInfo().getOffsetOfLocalArea();
for (unsigned i = 0, e = Objects.size(); i != e; ++i) {
const StackObject &SO = Objects[i];
OS << " <fi #" << (int)(i-NumFixedObjects) << "> is ";
if (SO.Size == 0)
OS << "variable sized";
else
OS << SO.Size << " byte" << (SO.Size != 1 ? "s" : " ");
if (i < NumFixedObjects)
OS << " fixed";
if (i < NumFixedObjects || SO.SPOffset != -1) {
int Off = SO.SPOffset + ValOffset;
OS << " at location [SP";
if (Off > 0)
OS << "+" << Off;
else if (Off < 0)
OS << Off;
OS << "]";
}
OS << "\n";
}
if (HasVarSizedObjects)
OS << " Stack frame contains variable sized objects\n";
}
void MachineFrameInfo::dump(const MachineFunction &MF) const {
print(MF, std::cerr);
}
//===----------------------------------------------------------------------===//
// MachineConstantPool implementation
//===----------------------------------------------------------------------===//
void MachineConstantPool::print(std::ostream &OS) const {
for (unsigned i = 0, e = Constants.size(); i != e; ++i)
OS << " <cp #" << i << "> is" << *(Value*)Constants[i] << "\n";
}
void MachineConstantPool::dump() const { print(std::cerr); }
//===----------------------------------------------------------------------===//
// MachineFunctionInfo implementation
//===----------------------------------------------------------------------===//
static unsigned
ComputeMaxOptionalArgsSize(const TargetMachine& target, const Function *F,
unsigned &maxOptionalNumArgs)
{
const TargetFrameInfo &frameInfo = target.getFrameInfo();
unsigned maxSize = 0;
for (Function::const_iterator BB = F->begin(), BBE = F->end(); BB !=BBE; ++BB)
for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E; ++I)
if (const CallInst *callInst = dyn_cast<CallInst>(I))
{
unsigned numOperands = callInst->getNumOperands() - 1;
int numExtra = (int)numOperands-frameInfo.getNumFixedOutgoingArgs();
if (numExtra <= 0)
continue;
unsigned sizeForThisCall;
if (frameInfo.argsOnStackHaveFixedSize())
{
int argSize = frameInfo.getSizeOfEachArgOnStack();
sizeForThisCall = numExtra * (unsigned) argSize;
}
else
{
assert(0 && "UNTESTED CODE: Size per stack argument is not "
"fixed on this architecture: use actual arg sizes to "
"compute MaxOptionalArgsSize");
sizeForThisCall = 0;
for (unsigned i = 0; i < numOperands; ++i)
sizeForThisCall += target.getTargetData().getTypeSize(callInst->
getOperand(i)->getType());
}
if (maxSize < sizeForThisCall)
maxSize = sizeForThisCall;
if ((int)maxOptionalNumArgs < numExtra)
maxOptionalNumArgs = (unsigned) numExtra;
}
return maxSize;
}
// Align data larger than one L1 cache line on L1 cache line boundaries.
// Align all smaller data on the next higher 2^x boundary (4, 8, ...),
// but not higher than the alignment of the largest type we support
// (currently a double word). -- see class TargetData).
//
// This function is similar to the corresponding function in EmitAssembly.cpp
// but they are unrelated. This one does not align at more than a
// double-word boundary whereas that one might.
//
inline unsigned
SizeToAlignment(unsigned size, const TargetMachine& target)
{
const unsigned short cacheLineSize = 16;
if (size > (unsigned) cacheLineSize / 2)
return cacheLineSize;
else
for (unsigned sz=1; /*no condition*/; sz *= 2)
if (sz >= size || sz >= target.getTargetData().getDoubleAlignment())
return sz;
}
void MachineFunctionInfo::CalculateArgSize() {
maxOptionalArgsSize = ComputeMaxOptionalArgsSize(MF.getTarget(),
MF.getFunction(),
maxOptionalNumArgs);
staticStackSize = maxOptionalArgsSize
+ MF.getTarget().getFrameInfo().getMinStackFrameSize();
}
int
MachineFunctionInfo::computeOffsetforLocalVar(const Value* val,
unsigned &getPaddedSize,
unsigned sizeToUse)
{
if (sizeToUse == 0)
sizeToUse = MF.getTarget().findOptimalStorageSize(val->getType());
unsigned align = SizeToAlignment(sizeToUse, MF.getTarget());
bool growUp;
int firstOffset = MF.getTarget().getFrameInfo().getFirstAutomaticVarOffset(MF,
growUp);
int offset = growUp? firstOffset + getAutomaticVarsSize()
: firstOffset - (getAutomaticVarsSize() + sizeToUse);
int aligned = MF.getTarget().getFrameInfo().adjustAlignment(offset, growUp, align);
getPaddedSize = sizeToUse + abs(aligned - offset);
return aligned;
}
int MachineFunctionInfo::allocateLocalVar(const Value* val,
unsigned sizeToUse) {
assert(! automaticVarsAreaFrozen &&
"Size of auto vars area has been used to compute an offset so "
"no more automatic vars should be allocated!");
// Check if we've allocated a stack slot for this value already
//
hash_map<const Value*, int>::const_iterator pair = offsets.find(val);
if (pair != offsets.end())
return pair->second;
unsigned getPaddedSize;
unsigned offset = computeOffsetforLocalVar(val, getPaddedSize, sizeToUse);
offsets[val] = offset;
incrementAutomaticVarsSize(getPaddedSize);
return offset;
}
int
MachineFunctionInfo::allocateSpilledValue(const Type* type)
{
assert(! spillsAreaFrozen &&
"Size of reg spills area has been used to compute an offset so "
"no more register spill slots should be allocated!");
unsigned size = MF.getTarget().getTargetData().getTypeSize(type);
unsigned char align = MF.getTarget().getTargetData().getTypeAlignment(type);
bool growUp;
int firstOffset = MF.getTarget().getFrameInfo().getRegSpillAreaOffset(MF, growUp);
int offset = growUp? firstOffset + getRegSpillsSize()
: firstOffset - (getRegSpillsSize() + size);
int aligned = MF.getTarget().getFrameInfo().adjustAlignment(offset, growUp, align);
size += abs(aligned - offset); // include alignment padding in size
incrementRegSpillsSize(size); // update size of reg. spills area
return aligned;
}
int
MachineFunctionInfo::pushTempValue(unsigned size)
{
unsigned align = SizeToAlignment(size, MF.getTarget());
bool growUp;
int firstOffset = MF.getTarget().getFrameInfo().getTmpAreaOffset(MF, growUp);
int offset = growUp? firstOffset + currentTmpValuesSize
: firstOffset - (currentTmpValuesSize + size);
int aligned = MF.getTarget().getFrameInfo().adjustAlignment(offset, growUp,
align);
size += abs(aligned - offset); // include alignment padding in size
incrementTmpAreaSize(size); // update "current" size of tmp area
return aligned;
}
void MachineFunctionInfo::popAllTempValues() {
resetTmpAreaSize(); // clear tmp area to reuse
}