llvm-6502/lib/CodeGen/MachineFunction.cpp
Bill Wendling 20c568f366 Add an "alignment" field to the MachineFunction object. It makes more sense to
have the alignment be calculated up front, and have the back-ends obey whatever
alignment is decided upon.

This allows for future work that would allow for precise no-op placement and the
like.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74564 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-30 22:38:32 +00:00

602 lines
20 KiB
C++

//===-- MachineFunction.cpp -----------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file 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/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/Instructions.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Config/config.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetFrameInfo.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/GraphWriter.h"
#include "llvm/Support/raw_ostream.h"
#include <fstream>
#include <sstream>
using namespace llvm;
bool MachineFunctionPass::runOnFunction(Function &F) {
// Do not codegen any 'available_externally' functions at all, they have
// definitions outside the translation unit.
if (F.hasAvailableExternallyLinkage())
return false;
return runOnMachineFunction(MachineFunction::get(&F));
}
namespace {
struct VISIBILITY_HIDDEN Printer : public MachineFunctionPass {
static char ID;
std::ostream *OS;
const std::string Banner;
Printer (std::ostream *os, const std::string &banner)
: MachineFunctionPass(&ID), 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;
}
};
char Printer::ID = 0;
}
/// 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 VISIBILITY_HIDDEN Deleter : public MachineFunctionPass {
static char ID;
Deleter() : MachineFunctionPass(&ID) {}
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;
}
};
char Deleter::ID = 0;
}
/// 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
//===---------------------------------------------------------------------===//
void ilist_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) {
MBB->getParent()->DeleteMachineBasicBlock(MBB);
}
MachineFunction::MachineFunction(const Function *F,
const TargetMachine &TM)
: Annotation(AnnotationManager::getID("CodeGen::MachineCodeForFunction")),
Fn(F), Target(TM) {
if (TM.getRegisterInfo())
RegInfo = new (Allocator.Allocate<MachineRegisterInfo>())
MachineRegisterInfo(*TM.getRegisterInfo());
else
RegInfo = 0;
MFInfo = 0;
FrameInfo = new (Allocator.Allocate<MachineFrameInfo>())
MachineFrameInfo(*TM.getFrameInfo());
ConstantPool = new (Allocator.Allocate<MachineConstantPool>())
MachineConstantPool(TM.getTargetData());
Alignment = TM.getTargetLowering()->getFunctionAlignment(F);
// Set up jump table.
const TargetData &TD = *TM.getTargetData();
bool IsPic = TM.getRelocationModel() == Reloc::PIC_;
unsigned EntrySize = IsPic ? 4 : TD.getPointerSize();
unsigned TyAlignment = IsPic ? TD.getABITypeAlignment(Type::Int32Ty)
: TD.getPointerABIAlignment();
JumpTableInfo = new (Allocator.Allocate<MachineJumpTableInfo>())
MachineJumpTableInfo(EntrySize, TyAlignment);
}
MachineFunction::~MachineFunction() {
BasicBlocks.clear();
InstructionRecycler.clear(Allocator);
BasicBlockRecycler.clear(Allocator);
if (RegInfo) {
RegInfo->~MachineRegisterInfo();
Allocator.Deallocate(RegInfo);
}
if (MFInfo) {
MFInfo->~MachineFunctionInfo();
Allocator.Deallocate(MFInfo);
}
FrameInfo->~MachineFrameInfo(); Allocator.Deallocate(FrameInfo);
ConstantPool->~MachineConstantPool(); Allocator.Deallocate(ConstantPool);
JumpTableInfo->~MachineJumpTableInfo(); Allocator.Deallocate(JumpTableInfo);
}
/// RenumberBlocks - This discards all of the MachineBasicBlock numbers and
/// recomputes them. This guarantees that the MBB numbers are sequential,
/// dense, and match the ordering of the blocks within the function. If a
/// specific MachineBasicBlock is specified, only that block and those after
/// it are renumbered.
void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) {
if (empty()) { MBBNumbering.clear(); return; }
MachineFunction::iterator MBBI, E = end();
if (MBB == 0)
MBBI = begin();
else
MBBI = MBB;
// Figure out the block number this should have.
unsigned BlockNo = 0;
if (MBBI != begin())
BlockNo = prior(MBBI)->getNumber()+1;
for (; MBBI != E; ++MBBI, ++BlockNo) {
if (MBBI->getNumber() != (int)BlockNo) {
// Remove use of the old number.
if (MBBI->getNumber() != -1) {
assert(MBBNumbering[MBBI->getNumber()] == &*MBBI &&
"MBB number mismatch!");
MBBNumbering[MBBI->getNumber()] = 0;
}
// If BlockNo is already taken, set that block's number to -1.
if (MBBNumbering[BlockNo])
MBBNumbering[BlockNo]->setNumber(-1);
MBBNumbering[BlockNo] = MBBI;
MBBI->setNumber(BlockNo);
}
}
// Okay, all the blocks are renumbered. If we have compactified the block
// numbering, shrink MBBNumbering now.
assert(BlockNo <= MBBNumbering.size() && "Mismatch!");
MBBNumbering.resize(BlockNo);
}
/// CreateMachineInstr - Allocate a new MachineInstr. Use this instead
/// of `new MachineInstr'.
///
MachineInstr *
MachineFunction::CreateMachineInstr(const TargetInstrDesc &TID,
DebugLoc DL, bool NoImp) {
return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
MachineInstr(TID, DL, NoImp);
}
/// CloneMachineInstr - Create a new MachineInstr which is a copy of the
/// 'Orig' instruction, identical in all ways except the the instruction
/// has no parent, prev, or next.
///
MachineInstr *
MachineFunction::CloneMachineInstr(const MachineInstr *Orig) {
return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
MachineInstr(*this, *Orig);
}
/// DeleteMachineInstr - Delete the given MachineInstr.
///
void
MachineFunction::DeleteMachineInstr(MachineInstr *MI) {
// Clear the instructions memoperands. This must be done manually because
// the instruction's parent pointer is now null, so it can't properly
// deallocate them on its own.
MI->clearMemOperands(*this);
MI->~MachineInstr();
InstructionRecycler.Deallocate(Allocator, MI);
}
/// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this
/// instead of `new MachineBasicBlock'.
///
MachineBasicBlock *
MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) {
return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator))
MachineBasicBlock(*this, bb);
}
/// DeleteMachineBasicBlock - Delete the given MachineBasicBlock.
///
void
MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) {
assert(MBB->getParent() == this && "MBB parent mismatch!");
MBB->~MachineBasicBlock();
BasicBlockRecycler.Deallocate(Allocator, MBB);
}
void MachineFunction::dump() const {
print(*cerr.stream());
}
void MachineFunction::print(std::ostream &OS) const {
OS << "# Machine code for " << Fn->getName () << "():\n";
// Print Frame Information
FrameInfo->print(*this, OS);
// Print JumpTable Information
JumpTableInfo->print(OS);
// Print Constant Pool
{
raw_os_ostream OSS(OS);
ConstantPool->print(OSS);
}
const TargetRegisterInfo *TRI = getTarget().getRegisterInfo();
if (RegInfo && !RegInfo->livein_empty()) {
OS << "Live Ins:";
for (MachineRegisterInfo::livein_iterator
I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) {
if (TRI)
OS << " " << TRI->getName(I->first);
else
OS << " Reg #" << I->first;
if (I->second)
OS << " in VR#" << I->second << " ";
}
OS << "\n";
}
if (RegInfo && !RegInfo->liveout_empty()) {
OS << "Live Outs:";
for (MachineRegisterInfo::liveout_iterator
I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I)
if (TRI)
OS << " " << TRI->getName(*I);
else
OS << " Reg #" << *I;
OS << "\n";
}
for (const_iterator BB = begin(); BB != end(); ++BB)
BB->print(OS);
OS << "\n# End machine code for " << Fn->getName () << "().\n\n";
}
namespace llvm {
template<>
struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits {
static std::string getGraphName(const MachineFunction *F) {
return "CFG for '" + F->getFunction()->getName() + "' function";
}
static std::string getNodeLabel(const MachineBasicBlock *Node,
const MachineFunction *Graph,
bool ShortNames) {
if (ShortNames && Node->getBasicBlock() &&
!Node->getBasicBlock()->getName().empty())
return Node->getBasicBlock()->getName() + ":";
std::ostringstream Out;
if (ShortNames) {
Out << Node->getNumber() << ':';
return Out.str();
}
Node->print(Out);
std::string OutStr = Out.str();
if (OutStr[0] == '\n') OutStr.erase(OutStr.begin());
// Process string output to make it nicer...
for (unsigned i = 0; i != OutStr.length(); ++i)
if (OutStr[i] == '\n') { // Left justify
OutStr[i] = '\\';
OutStr.insert(OutStr.begin()+i+1, 'l');
}
return OutStr;
}
};
}
void MachineFunction::viewCFG() const
{
#ifndef NDEBUG
ViewGraph(this, "mf" + getFunction()->getName());
#else
cerr << "SelectionDAG::viewGraph is only available in debug builds on "
<< "systems with Graphviz or gv!\n";
#endif // NDEBUG
}
void MachineFunction::viewCFGOnly() const
{
#ifndef NDEBUG
ViewGraph(this, "mf" + getFunction()->getName(), true);
#else
cerr << "SelectionDAG::viewGraph is only available in debug builds on "
<< "systems with Graphviz or gv!\n";
#endif // NDEBUG
}
// 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)
{
AnnotationID MF_AID =
AnnotationManager::getID("CodeGen::MachineCodeForFunction");
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) {
AnnotationID MF_AID =
AnnotationManager::getID("CodeGen::MachineCodeForFunction");
bool Deleted = Fn->deleteAnnotation(MF_AID);
assert(Deleted && "Machine code did not exist for function!");
Deleted = Deleted; // silence warning when no assertions.
}
MachineFunction& MachineFunction::get(const Function *F)
{
AnnotationID MF_AID =
AnnotationManager::getID("CodeGen::MachineCodeForFunction");
MachineFunction *mc = (MachineFunction*)F->getAnnotation(MF_AID);
assert(mc && "Call construct() method first to allocate the object");
return *mc;
}
/// addLiveIn - Add the specified physical register as a live-in value and
/// create a corresponding virtual register for it.
unsigned MachineFunction::addLiveIn(unsigned PReg,
const TargetRegisterClass *RC) {
assert(RC->contains(PReg) && "Not the correct regclass!");
unsigned VReg = getRegInfo().createVirtualRegister(RC);
getRegInfo().addLiveIn(PReg, VReg);
return VReg;
}
/// getOrCreateDebugLocID - Look up the DebugLocTuple index with the given
/// source file, line, and column. If none currently exists, create a new
/// DebugLocTuple, and insert it into the DebugIdMap.
unsigned MachineFunction::getOrCreateDebugLocID(GlobalVariable *CompileUnit,
unsigned Line, unsigned Col) {
DebugLocTuple Tuple(CompileUnit, Line, Col);
DenseMap<DebugLocTuple, unsigned>::iterator II
= DebugLocInfo.DebugIdMap.find(Tuple);
if (II != DebugLocInfo.DebugIdMap.end())
return II->second;
// Add a new tuple.
unsigned Id = DebugLocInfo.DebugLocations.size();
DebugLocInfo.DebugLocations.push_back(Tuple);
DebugLocInfo.DebugIdMap[Tuple] = Id;
return Id;
}
/// getDebugLocTuple - Get the DebugLocTuple for a given DebugLoc object.
DebugLocTuple MachineFunction::getDebugLocTuple(DebugLoc DL) const {
unsigned Idx = DL.getIndex();
assert(Idx < DebugLocInfo.DebugLocations.size() &&
"Invalid index into debug locations!");
return DebugLocInfo.DebugLocations[Idx];
}
//===----------------------------------------------------------------------===//
// MachineFrameInfo implementation
//===----------------------------------------------------------------------===//
/// CreateFixedObject - Create a new object at a fixed location on the stack.
/// All fixed objects should be created before other objects are created for
/// efficiency. By default, fixed objects are immutable. This returns an
/// index with a negative value.
///
int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset,
bool Immutable) {
assert(Size != 0 && "Cannot allocate zero size fixed stack objects!");
Objects.insert(Objects.begin(), StackObject(Size, 1, SPOffset, Immutable));
return -++NumFixedObjects;
}
void MachineFrameInfo::print(const MachineFunction &MF, std::ostream &OS) const{
const TargetFrameInfo *FI = MF.getTarget().getFrameInfo();
int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0);
for (unsigned i = 0, e = Objects.size(); i != e; ++i) {
const StackObject &SO = Objects[i];
OS << " <fi#" << (int)(i-NumFixedObjects) << ">: ";
if (SO.Size == ~0ULL) {
OS << "dead\n";
continue;
}
if (SO.Size == 0)
OS << "variable sized";
else
OS << "size is " << SO.Size << " byte" << (SO.Size != 1 ? "s," : ",");
OS << " alignment is " << SO.Alignment << " byte"
<< (SO.Alignment != 1 ? "s," : ",");
if (i < NumFixedObjects)
OS << " fixed";
if (i < NumFixedObjects || SO.SPOffset != -1) {
int64_t 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, *cerr.stream());
}
//===----------------------------------------------------------------------===//
// MachineJumpTableInfo implementation
//===----------------------------------------------------------------------===//
/// getJumpTableIndex - Create a new jump table entry in the jump table info
/// or return an existing one.
///
unsigned MachineJumpTableInfo::getJumpTableIndex(
const std::vector<MachineBasicBlock*> &DestBBs) {
assert(!DestBBs.empty() && "Cannot create an empty jump table!");
for (unsigned i = 0, e = JumpTables.size(); i != e; ++i)
if (JumpTables[i].MBBs == DestBBs)
return i;
JumpTables.push_back(MachineJumpTableEntry(DestBBs));
return JumpTables.size()-1;
}
/// ReplaceMBBInJumpTables - If Old is the target of any jump tables, update
/// the jump tables to branch to New instead.
bool
MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old,
MachineBasicBlock *New) {
assert(Old != New && "Not making a change?");
bool MadeChange = false;
for (size_t i = 0, e = JumpTables.size(); i != e; ++i) {
MachineJumpTableEntry &JTE = JumpTables[i];
for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j)
if (JTE.MBBs[j] == Old) {
JTE.MBBs[j] = New;
MadeChange = true;
}
}
return MadeChange;
}
void MachineJumpTableInfo::print(std::ostream &OS) const {
// FIXME: this is lame, maybe we could print out the MBB numbers or something
// like {1, 2, 4, 5, 3, 0}
for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) {
OS << " <jt#" << i << "> has " << JumpTables[i].MBBs.size()
<< " entries\n";
}
}
void MachineJumpTableInfo::dump() const { print(*cerr.stream()); }
//===----------------------------------------------------------------------===//
// MachineConstantPool implementation
//===----------------------------------------------------------------------===//
const Type *MachineConstantPoolEntry::getType() const {
if (isMachineConstantPoolEntry())
return Val.MachineCPVal->getType();
return Val.ConstVal->getType();
}
MachineConstantPool::~MachineConstantPool() {
for (unsigned i = 0, e = Constants.size(); i != e; ++i)
if (Constants[i].isMachineConstantPoolEntry())
delete Constants[i].Val.MachineCPVal;
}
/// getConstantPoolIndex - Create a new entry in the constant pool or return
/// an existing one. User must specify the log2 of the minimum required
/// alignment for the object.
///
unsigned MachineConstantPool::getConstantPoolIndex(Constant *C,
unsigned Alignment) {
assert(Alignment && "Alignment must be specified!");
if (Alignment > PoolAlignment) PoolAlignment = Alignment;
// Check to see if we already have this constant.
//
// FIXME, this could be made much more efficient for large constant pools.
for (unsigned i = 0, e = Constants.size(); i != e; ++i)
if (Constants[i].Val.ConstVal == C &&
(Constants[i].getAlignment() & (Alignment - 1)) == 0)
return i;
Constants.push_back(MachineConstantPoolEntry(C, Alignment));
return Constants.size()-1;
}
unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V,
unsigned Alignment) {
assert(Alignment && "Alignment must be specified!");
if (Alignment > PoolAlignment) PoolAlignment = Alignment;
// Check to see if we already have this constant.
//
// FIXME, this could be made much more efficient for large constant pools.
int Idx = V->getExistingMachineCPValue(this, Alignment);
if (Idx != -1)
return (unsigned)Idx;
Constants.push_back(MachineConstantPoolEntry(V, Alignment));
return Constants.size()-1;
}
void MachineConstantPool::print(raw_ostream &OS) const {
for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
OS << " <cp#" << i << "> is";
if (Constants[i].isMachineConstantPoolEntry())
Constants[i].Val.MachineCPVal->print(OS);
else
OS << *(Value*)Constants[i].Val.ConstVal;
OS << " , alignment=" << Constants[i].getAlignment();
OS << "\n";
}
}
void MachineConstantPool::dump() const { print(errs()); }