llvm-6502/lib/CodeGen/MachineFunction.cpp

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//===-- 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/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/TargetMachine.h"
#include "llvm/Target/TargetFrameInfo.h"
#include "llvm/Function.h"
#include "llvm/Instructions.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/GraphWriter.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Config/config.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());
// Set up jump table.
const TargetData &TD = *TM.getTargetData();
bool IsPic = TM.getRelocationModel() == Reloc::PIC_;
unsigned EntrySize = IsPic ? 4 : TD.getPointerSize();
unsigned Alignment = IsPic ? TD.getABITypeAlignment(Type::Int32Ty)
: TD.getPointerABIAlignment();
JumpTableInfo = new (Allocator.Allocate<MachineJumpTableInfo>())
MachineJumpTableInfo(EntrySize, Alignment);
}
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";
}
/// CFGOnly flag - This is used to control whether or not the CFG graph printer
/// prints out the contents of basic blocks or not. This is acceptable because
/// this code is only really used for debugging purposes.
///
static bool CFGOnly = false;
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) {
if (CFGOnly && Node->getBasicBlock() &&
!Node->getBasicBlock()->getName().empty())
return Node->getBasicBlock()->getName() + ":";
std::ostringstream Out;
if (CFGOnly) {
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
{
CFGOnly = true;
viewCFG();
CFGOnly = false;
}
// 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)
Fix some significant problems with constant pools that resulted in unnecessary paddings between constant pool entries, larger than necessary alignments (e.g. 8 byte alignment for .literal4 sections), and potentially other issues. 1. ConstantPoolSDNode alignment field is log2 value of the alignment requirement. This is not consistent with other SDNode variants. 2. MachineConstantPool alignment field is also a log2 value. 3. However, some places are creating ConstantPoolSDNode with alignment value rather than log2 values. This creates entries with artificially large alignments, e.g. 256 for SSE vector values. 4. Constant pool entry offsets are computed when they are created. However, asm printer group them by sections. That means the offsets are no longer valid. However, asm printer uses them to determine size of padding between entries. 5. Asm printer uses expensive data structure multimap to track constant pool entries by sections. 6. Asm printer iterate over SmallPtrSet when it's emitting constant pool entries. This is non-deterministic. Solutions: 1. ConstantPoolSDNode alignment field is changed to keep non-log2 value. 2. MachineConstantPool alignment field is also changed to keep non-log2 value. 3. Functions that create ConstantPool nodes are passing in non-log2 alignments. 4. MachineConstantPoolEntry no longer keeps an offset field. It's replaced with an alignment field. Offsets are not computed when constant pool entries are created. They are computed on the fly in asm printer and JIT. 5. Asm printer uses cheaper data structure to group constant pool entries. 6. Asm printer compute entry offsets after grouping is done. 7. Change JIT code to compute entry offsets on the fly. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66875 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-13 07:51:59 +00:00
if (Constants[i].Val.ConstVal == C &&
(Constants[i].getAlignment() & (Alignment - 1)) == 0)
return i;
Fix some significant problems with constant pools that resulted in unnecessary paddings between constant pool entries, larger than necessary alignments (e.g. 8 byte alignment for .literal4 sections), and potentially other issues. 1. ConstantPoolSDNode alignment field is log2 value of the alignment requirement. This is not consistent with other SDNode variants. 2. MachineConstantPool alignment field is also a log2 value. 3. However, some places are creating ConstantPoolSDNode with alignment value rather than log2 values. This creates entries with artificially large alignments, e.g. 256 for SSE vector values. 4. Constant pool entry offsets are computed when they are created. However, asm printer group them by sections. That means the offsets are no longer valid. However, asm printer uses them to determine size of padding between entries. 5. Asm printer uses expensive data structure multimap to track constant pool entries by sections. 6. Asm printer iterate over SmallPtrSet when it's emitting constant pool entries. This is non-deterministic. Solutions: 1. ConstantPoolSDNode alignment field is changed to keep non-log2 value. 2. MachineConstantPool alignment field is also changed to keep non-log2 value. 3. Functions that create ConstantPool nodes are passing in non-log2 alignments. 4. MachineConstantPoolEntry no longer keeps an offset field. It's replaced with an alignment field. Offsets are not computed when constant pool entries are created. They are computed on the fly in asm printer and JIT. 5. Asm printer uses cheaper data structure to group constant pool entries. 6. Asm printer compute entry offsets after grouping is done. 7. Change JIT code to compute entry offsets on the fly. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66875 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-13 07:51:59 +00:00
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;
Fix some significant problems with constant pools that resulted in unnecessary paddings between constant pool entries, larger than necessary alignments (e.g. 8 byte alignment for .literal4 sections), and potentially other issues. 1. ConstantPoolSDNode alignment field is log2 value of the alignment requirement. This is not consistent with other SDNode variants. 2. MachineConstantPool alignment field is also a log2 value. 3. However, some places are creating ConstantPoolSDNode with alignment value rather than log2 values. This creates entries with artificially large alignments, e.g. 256 for SSE vector values. 4. Constant pool entry offsets are computed when they are created. However, asm printer group them by sections. That means the offsets are no longer valid. However, asm printer uses them to determine size of padding between entries. 5. Asm printer uses expensive data structure multimap to track constant pool entries by sections. 6. Asm printer iterate over SmallPtrSet when it's emitting constant pool entries. This is non-deterministic. Solutions: 1. ConstantPoolSDNode alignment field is changed to keep non-log2 value. 2. MachineConstantPool alignment field is also changed to keep non-log2 value. 3. Functions that create ConstantPool nodes are passing in non-log2 alignments. 4. MachineConstantPoolEntry no longer keeps an offset field. It's replaced with an alignment field. Offsets are not computed when constant pool entries are created. They are computed on the fly in asm printer and JIT. 5. Asm printer uses cheaper data structure to group constant pool entries. 6. Asm printer compute entry offsets after grouping is done. 7. Change JIT code to compute entry offsets on the fly. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66875 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-13 07:51:59 +00:00
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;
Fix some significant problems with constant pools that resulted in unnecessary paddings between constant pool entries, larger than necessary alignments (e.g. 8 byte alignment for .literal4 sections), and potentially other issues. 1. ConstantPoolSDNode alignment field is log2 value of the alignment requirement. This is not consistent with other SDNode variants. 2. MachineConstantPool alignment field is also a log2 value. 3. However, some places are creating ConstantPoolSDNode with alignment value rather than log2 values. This creates entries with artificially large alignments, e.g. 256 for SSE vector values. 4. Constant pool entry offsets are computed when they are created. However, asm printer group them by sections. That means the offsets are no longer valid. However, asm printer uses them to determine size of padding between entries. 5. Asm printer uses expensive data structure multimap to track constant pool entries by sections. 6. Asm printer iterate over SmallPtrSet when it's emitting constant pool entries. This is non-deterministic. Solutions: 1. ConstantPoolSDNode alignment field is changed to keep non-log2 value. 2. MachineConstantPool alignment field is also changed to keep non-log2 value. 3. Functions that create ConstantPool nodes are passing in non-log2 alignments. 4. MachineConstantPoolEntry no longer keeps an offset field. It's replaced with an alignment field. Offsets are not computed when constant pool entries are created. They are computed on the fly in asm printer and JIT. 5. Asm printer uses cheaper data structure to group constant pool entries. 6. Asm printer compute entry offsets after grouping is done. 7. Change JIT code to compute entry offsets on the fly. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66875 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-13 07:51:59 +00:00
OS << " , alignment=" << Constants[i].getAlignment();
OS << "\n";
}
}
void MachineConstantPool::dump() const { print(errs()); }