RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-10-19 19:12:56 +02:00
Code Issues Projects Releases Wiki Activity
553c9adc29
llvm-mirror/lib/CodeGen/MachineFunction.cpp
Ahmed Bougacha e7864c5269 [GlobalISel] Add Selected MachineFunction property. 
Selected: the InstructionSelect pass ran and all pre-isel generic
instructions have been eliminated; i.e., all instructions are now
target-specific or non-pre-isel generic instructions (e.g., COPY).

Since only pre-isel generic instructions can have generic virtual register
operands, this also means that all generic virtual registers have been
constrained to virtual registers (assigned to register classes) and that
all sizes attached to them have been eliminated.

This lets us enforce certain invariants across passes.
This property is GlobalISel-specific, but is always available.

llvm-svn: 277482
2016-08-02 16:49:19 +00:00

1017 lines
37 KiB
C++
Raw Blame History

//===-- 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/CodeGen/MachineFunction.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/EHPersonalities.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunctionInitializer.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/PseudoSourceValue.h"
#include "llvm/CodeGen/WinEHFuncInfo.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/ModuleSlotTracker.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/GraphWriter.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetFrameLowering.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetSubtargetInfo.h"
using namespace llvm;
#define DEBUG_TYPE "codegen"
static cl::opt<unsigned>
AlignAllFunctions("align-all-functions",
cl::desc("Force the alignment of all functions."),
cl::init(0), cl::Hidden);
void MachineFunctionInitializer::anchor() {}
void MachineFunctionProperties::print(raw_ostream &ROS, bool OnlySet) const {
// Leave this function even in NDEBUG as an out-of-line anchor.
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
bool NeedsComma = false;
for (BitVector::size_type i = 0; i < Properties.size(); ++i) {
bool HasProperty = Properties[i];
if (OnlySet && !HasProperty)
continue;
if (NeedsComma)
ROS << ", ";
else
NeedsComma = true;
switch(static_cast<Property>(i)) {
case Property::IsSSA:
ROS << (HasProperty ? "SSA" : "Post SSA");
break;
case Property::TracksLiveness:
ROS << (HasProperty ? "" : "not ") << "tracking liveness";
break;
case Property::AllVRegsAllocated:
ROS << (HasProperty ? "AllVRegsAllocated" : "HasVRegs");
break;
case Property::Legalized:
ROS << (HasProperty ? "" : "not ") << "legalized";
break;
case Property::RegBankSelected:
ROS << (HasProperty ? "" : "not ") << "RegBank-selected";
break;
case Property::Selected:
ROS << (HasProperty ? "" : "not ") << "selected";
break;
default:
break;
}
}
#endif
}
//===----------------------------------------------------------------------===//
// MachineFunction implementation
//===----------------------------------------------------------------------===//
// Out-of-line virtual method.
MachineFunctionInfo::~MachineFunctionInfo() {}
void ilist_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) {
MBB->getParent()->DeleteMachineBasicBlock(MBB);
}
static inline unsigned getFnStackAlignment(const TargetSubtargetInfo *STI,
const Function *Fn) {
if (Fn->hasFnAttribute(Attribute::StackAlignment))
return Fn->getFnStackAlignment();
return STI->getFrameLowering()->getStackAlignment();
}
MachineFunction::MachineFunction(const Function *F, const TargetMachine &TM,
unsigned FunctionNum, MachineModuleInfo &mmi)
: Fn(F), Target(TM), STI(TM.getSubtargetImpl(*F)), Ctx(mmi.getContext()),
MMI(mmi) {
// Assume the function starts in SSA form with correct liveness.
Properties.set(MachineFunctionProperties::Property::IsSSA);
Properties.set(MachineFunctionProperties::Property::TracksLiveness);
if (STI->getRegisterInfo())
RegInfo = new (Allocator) MachineRegisterInfo(this);
else
RegInfo = nullptr;
MFInfo = nullptr;
// We can realign the stack if the target supports it and the user hasn't
// explicitly asked us not to.
bool CanRealignSP = STI->getFrameLowering()->isStackRealignable() &&
!F->hasFnAttribute("no-realign-stack");
FrameInfo = new (Allocator) MachineFrameInfo(
getFnStackAlignment(STI, Fn), /*StackRealignable=*/CanRealignSP,
/*ForceRealign=*/CanRealignSP &&
F->hasFnAttribute(Attribute::StackAlignment));
if (Fn->hasFnAttribute(Attribute::StackAlignment))
FrameInfo->ensureMaxAlignment(Fn->getFnStackAlignment());
ConstantPool = new (Allocator) MachineConstantPool(getDataLayout());
Alignment = STI->getTargetLowering()->getMinFunctionAlignment();
// FIXME: Shouldn't use pref alignment if explicit alignment is set on Fn.
// FIXME: Use Function::optForSize().
if (!Fn->hasFnAttribute(Attribute::OptimizeForSize))
Alignment = std::max(Alignment,
STI->getTargetLowering()->getPrefFunctionAlignment());
if (AlignAllFunctions)
Alignment = AlignAllFunctions;
FunctionNumber = FunctionNum;
JumpTableInfo = nullptr;
if (isFuncletEHPersonality(classifyEHPersonality(
F->hasPersonalityFn() ? F->getPersonalityFn() : nullptr))) {
WinEHInfo = new (Allocator) WinEHFuncInfo();
}
assert(TM.isCompatibleDataLayout(getDataLayout()) &&
"Can't create a MachineFunction using a Module with a "
"Target-incompatible DataLayout attached\n");
PSVManager = llvm::make_unique<PseudoSourceValueManager>();
}
MachineFunction::~MachineFunction() {
// Don't call destructors on MachineInstr and MachineOperand. All of their
// memory comes from the BumpPtrAllocator which is about to be purged.
//
// Do call MachineBasicBlock destructors, it contains std::vectors.
for (iterator I = begin(), E = end(); I != E; I = BasicBlocks.erase(I))
I->Insts.clearAndLeakNodesUnsafely();
InstructionRecycler.clear(Allocator);
OperandRecycler.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);
if (JumpTableInfo) {
JumpTableInfo->~MachineJumpTableInfo();
Allocator.Deallocate(JumpTableInfo);
}
if (WinEHInfo) {
WinEHInfo->~WinEHFuncInfo();
Allocator.Deallocate(WinEHInfo);
}
}
const DataLayout &MachineFunction::getDataLayout() const {
return Fn->getParent()->getDataLayout();
}
/// Get the JumpTableInfo for this function.
/// If it does not already exist, allocate one.
MachineJumpTableInfo *MachineFunction::
getOrCreateJumpTableInfo(unsigned EntryKind) {
if (JumpTableInfo) return JumpTableInfo;
JumpTableInfo = new (Allocator)
MachineJumpTableInfo((MachineJumpTableInfo::JTEntryKind)EntryKind);
return JumpTableInfo;
}
/// Should we be emitting segmented stack stuff for the function
bool MachineFunction::shouldSplitStack() const {
return getFunction()->hasFnAttribute("split-stack");
}
/// 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 == nullptr)
MBBI = begin();
else
MBBI = MBB->getIterator();
// Figure out the block number this should have.
unsigned BlockNo = 0;
if (MBBI != begin())
BlockNo = std::prev(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()] = nullptr;
}
// 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);
}
/// Allocate a new MachineInstr. Use this instead of `new MachineInstr'.
MachineInstr *MachineFunction::CreateMachineInstr(const MCInstrDesc &MCID,
const DebugLoc &DL,
bool NoImp) {
return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
MachineInstr(*this, MCID, DL, NoImp);
}
/// Create a new MachineInstr which is a copy of the 'Orig' instruction,
/// identical in all ways except the instruction has no parent, prev, or next.
MachineInstr *
MachineFunction::CloneMachineInstr(const MachineInstr *Orig) {
return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
MachineInstr(*this, *Orig);
}
/// Delete the given MachineInstr.
///
/// This function also serves as the MachineInstr destructor - the real
/// ~MachineInstr() destructor must be empty.
void
MachineFunction::DeleteMachineInstr(MachineInstr *MI) {
// Strip it for parts. The operand array and the MI object itself are
// independently recyclable.
if (MI->Operands)
deallocateOperandArray(MI->CapOperands, MI->Operands);
// Don't call ~MachineInstr() which must be trivial anyway because
// ~MachineFunction drops whole lists of MachineInstrs wihout calling their
// destructors.
InstructionRecycler.Deallocate(Allocator, MI);
}
/// 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);
}
/// Delete the given MachineBasicBlock.
void
MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) {
assert(MBB->getParent() == this && "MBB parent mismatch!");
MBB->~MachineBasicBlock();
BasicBlockRecycler.Deallocate(Allocator, MBB);
}
MachineMemOperand *MachineFunction::getMachineMemOperand(
MachinePointerInfo PtrInfo, MachineMemOperand::Flags f, uint64_t s,
unsigned base_alignment, const AAMDNodes &AAInfo, const MDNode *Ranges) {
return new (Allocator)
MachineMemOperand(PtrInfo, f, s, base_alignment, AAInfo, Ranges);
}
MachineMemOperand *
MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
int64_t Offset, uint64_t Size) {
if (MMO->getValue())
return new (Allocator)
MachineMemOperand(MachinePointerInfo(MMO->getValue(),
MMO->getOffset()+Offset),
MMO->getFlags(), Size,
MMO->getBaseAlignment());
return new (Allocator)
MachineMemOperand(MachinePointerInfo(MMO->getPseudoValue(),
MMO->getOffset()+Offset),
MMO->getFlags(), Size,
MMO->getBaseAlignment());
}
MachineInstr::mmo_iterator
MachineFunction::allocateMemRefsArray(unsigned long Num) {
return Allocator.Allocate<MachineMemOperand *>(Num);
}
std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator>
MachineFunction::extractLoadMemRefs(MachineInstr::mmo_iterator Begin,
MachineInstr::mmo_iterator End) {
// Count the number of load mem refs.
unsigned Num = 0;
for (MachineInstr::mmo_iterator I = Begin; I != End; ++I)
if ((*I)->isLoad())
++Num;
// Allocate a new array and populate it with the load information.
MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num);
unsigned Index = 0;
for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) {
if ((*I)->isLoad()) {
if (!(*I)->isStore())
// Reuse the MMO.
Result[Index] = *I;
else {
// Clone the MMO and unset the store flag.
MachineMemOperand *JustLoad =
getMachineMemOperand((*I)->getPointerInfo(),
(*I)->getFlags() & ~MachineMemOperand::MOStore,
(*I)->getSize(), (*I)->getBaseAlignment(),
(*I)->getAAInfo());
Result[Index] = JustLoad;
}
++Index;
}
}
return std::make_pair(Result, Result + Num);
}
std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator>
MachineFunction::extractStoreMemRefs(MachineInstr::mmo_iterator Begin,
MachineInstr::mmo_iterator End) {
// Count the number of load mem refs.
unsigned Num = 0;
for (MachineInstr::mmo_iterator I = Begin; I != End; ++I)
if ((*I)->isStore())
++Num;
// Allocate a new array and populate it with the store information.
MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num);
unsigned Index = 0;
for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) {
if ((*I)->isStore()) {
if (!(*I)->isLoad())
// Reuse the MMO.
Result[Index] = *I;
else {
// Clone the MMO and unset the load flag.
MachineMemOperand *JustStore =
getMachineMemOperand((*I)->getPointerInfo(),
(*I)->getFlags() & ~MachineMemOperand::MOLoad,
(*I)->getSize(), (*I)->getBaseAlignment(),
(*I)->getAAInfo());
Result[Index] = JustStore;
}
++Index;
}
}
return std::make_pair(Result, Result + Num);
}
const char *MachineFunction::createExternalSymbolName(StringRef Name) {
char *Dest = Allocator.Allocate<char>(Name.size() + 1);
std::copy(Name.begin(), Name.end(), Dest);
Dest[Name.size()] = 0;
return Dest;
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
LLVM_DUMP_METHOD void MachineFunction::dump() const {
print(dbgs());
}
#endif
StringRef MachineFunction::getName() const {
assert(getFunction() && "No function!");
return getFunction()->getName();
}
void MachineFunction::print(raw_ostream &OS, const SlotIndexes *Indexes) const {
OS << "# Machine code for function " << getName() << ": ";
OS << "Properties: <";
getProperties().print(OS);
OS << ">\n";
// Print Frame Information
FrameInfo->print(*this, OS);
// Print JumpTable Information
if (JumpTableInfo)
JumpTableInfo->print(OS);
// Print Constant Pool
ConstantPool->print(OS);
const TargetRegisterInfo *TRI = getSubtarget().getRegisterInfo();
if (RegInfo && !RegInfo->livein_empty()) {
OS << "Function Live Ins: ";
for (MachineRegisterInfo::livein_iterator
I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) {
OS << PrintReg(I->first, TRI);
if (I->second)
OS << " in " << PrintReg(I->second, TRI);
if (std::next(I) != E)
OS << ", ";
}
OS << '\n';
}
ModuleSlotTracker MST(getFunction()->getParent());
MST.incorporateFunction(*getFunction());
for (const auto &BB : *this) {
OS << '\n';
BB.print(OS, MST, Indexes);
}
OS << "\n# End machine code for function " << getName() << ".\n\n";
}
namespace llvm {
template<>
struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits {
DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {}
static std::string getGraphName(const MachineFunction *F) {
return ("CFG for '" + F->getName() + "' function").str();
}
std::string getNodeLabel(const MachineBasicBlock *Node,
const MachineFunction *Graph) {
std::string OutStr;
{
raw_string_ostream OSS(OutStr);
if (isSimple()) {
OSS << "BB#" << Node->getNumber();
if (const BasicBlock *BB = Node->getBasicBlock())
OSS << ": " << BB->getName();
} else
Node->print(OSS);
}
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" + getName());
#else
errs() << "MachineFunction::viewCFG is only available in debug builds on "
<< "systems with Graphviz or gv!\n";
#endif // NDEBUG
}
void MachineFunction::viewCFGOnly() const
{
#ifndef NDEBUG
ViewGraph(this, "mf" + getName(), true);
#else
errs() << "MachineFunction::viewCFGOnly is only available in debug builds on "
<< "systems with Graphviz or gv!\n";
#endif // NDEBUG
}
/// 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) {
MachineRegisterInfo &MRI = getRegInfo();
unsigned VReg = MRI.getLiveInVirtReg(PReg);
if (VReg) {
const TargetRegisterClass *VRegRC = MRI.getRegClass(VReg);
(void)VRegRC;
// A physical register can be added several times.
// Between two calls, the register class of the related virtual register
// may have been constrained to match some operation constraints.
// In that case, check that the current register class includes the
// physical register and is a sub class of the specified RC.
assert((VRegRC == RC || (VRegRC->contains(PReg) &&
RC->hasSubClassEq(VRegRC))) &&
"Register class mismatch!");
return VReg;
}
VReg = MRI.createVirtualRegister(RC);
MRI.addLiveIn(PReg, VReg);
return VReg;
}
/// Return the MCSymbol for the specified non-empty jump table.
/// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a
/// normal 'L' label is returned.
MCSymbol *MachineFunction::getJTISymbol(unsigned JTI, MCContext &Ctx,
bool isLinkerPrivate) const {
const DataLayout &DL = getDataLayout();
assert(JumpTableInfo && "No jump tables");
assert(JTI < JumpTableInfo->getJumpTables().size() && "Invalid JTI!");
const char *Prefix = isLinkerPrivate ? DL.getLinkerPrivateGlobalPrefix()
: DL.getPrivateGlobalPrefix();
SmallString<60> Name;
raw_svector_ostream(Name)
<< Prefix << "JTI" << getFunctionNumber() << '_' << JTI;
return Ctx.getOrCreateSymbol(Name);
}
/// Return a function-local symbol to represent the PIC base.
MCSymbol *MachineFunction::getPICBaseSymbol() const {
const DataLayout &DL = getDataLayout();
return Ctx.getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
Twine(getFunctionNumber()) + "$pb");
}
//===----------------------------------------------------------------------===//
// MachineFrameInfo implementation
//===----------------------------------------------------------------------===//
/// Make sure the function is at least Align bytes aligned.
void MachineFrameInfo::ensureMaxAlignment(unsigned Align) {
if (!StackRealignable)
assert(Align <= StackAlignment &&
"For targets without stack realignment, Align is out of limit!");
if (MaxAlignment < Align) MaxAlignment = Align;
}
/// Clamp the alignment if requested and emit a warning.
static inline unsigned clampStackAlignment(bool ShouldClamp, unsigned Align,
unsigned StackAlign) {
if (!ShouldClamp || Align <= StackAlign)
return Align;
DEBUG(dbgs() << "Warning: requested alignment " << Align
<< " exceeds the stack alignment " << StackAlign
<< " when stack realignment is off" << '\n');
return StackAlign;
}
/// Create a new statically sized stack object, returning a nonnegative
/// identifier to represent it.
int MachineFrameInfo::CreateStackObject(uint64_t Size, unsigned Alignment,
bool isSS, const AllocaInst *Alloca) {
assert(Size != 0 && "Cannot allocate zero size stack objects!");
Alignment = clampStackAlignment(!StackRealignable, Alignment, StackAlignment);
Objects.push_back(StackObject(Size, Alignment, 0, false, isSS, Alloca,
!isSS));
int Index = (int)Objects.size() - NumFixedObjects - 1;
assert(Index >= 0 && "Bad frame index!");
ensureMaxAlignment(Alignment);
return Index;
}
/// Create a new statically sized stack object that represents a spill slot,
/// returning a nonnegative identifier to represent it.
int MachineFrameInfo::CreateSpillStackObject(uint64_t Size,
unsigned Alignment) {
Alignment = clampStackAlignment(!StackRealignable, Alignment, StackAlignment);
CreateStackObject(Size, Alignment, true);
int Index = (int)Objects.size() - NumFixedObjects - 1;
ensureMaxAlignment(Alignment);
return Index;
}
/// Notify the MachineFrameInfo object that a variable sized object has been
/// created. This must be created whenever a variable sized object is created,
/// whether or not the index returned is actually used.
int MachineFrameInfo::CreateVariableSizedObject(unsigned Alignment,
const AllocaInst *Alloca) {
HasVarSizedObjects = true;
Alignment = clampStackAlignment(!StackRealignable, Alignment, StackAlignment);
Objects.push_back(StackObject(0, Alignment, 0, false, false, Alloca, true));
ensureMaxAlignment(Alignment);
return (int)Objects.size()-NumFixedObjects-1;
}
/// 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, bool isAliased) {
assert(Size != 0 && "Cannot allocate zero size fixed stack objects!");
// The alignment of the frame index can be determined from its offset from
// the incoming frame position. If the frame object is at offset 32 and
// the stack is guaranteed to be 16-byte aligned, then we know that the
// object is 16-byte aligned. Note that unlike the non-fixed case, if the
// stack needs realignment, we can't assume that the stack will in fact be
// aligned.
unsigned Align = MinAlign(SPOffset, ForcedRealign ? 1 : StackAlignment);
Align = clampStackAlignment(!StackRealignable, Align, StackAlignment);
Objects.insert(Objects.begin(), StackObject(Size, Align, SPOffset, Immutable,
/*isSS*/ false,
/*Alloca*/ nullptr, isAliased));
return -++NumFixedObjects;
}
/// Create a spill slot at a fixed location on the stack.
/// Returns an index with a negative value.
int MachineFrameInfo::CreateFixedSpillStackObject(uint64_t Size,
int64_t SPOffset) {
unsigned Align = MinAlign(SPOffset, ForcedRealign ? 1 : StackAlignment);
Align = clampStackAlignment(!StackRealignable, Align, StackAlignment);
Objects.insert(Objects.begin(), StackObject(Size, Align, SPOffset,
/*Immutable*/ true,
/*isSS*/ true,
/*Alloca*/ nullptr,
/*isAliased*/ false));
return -++NumFixedObjects;
}
BitVector MachineFrameInfo::getPristineRegs(const MachineFunction &MF) const {
const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
BitVector BV(TRI->getNumRegs());
// Before CSI is calculated, no registers are considered pristine. They can be
// freely used and PEI will make sure they are saved.
if (!isCalleeSavedInfoValid())
return BV;
for (const MCPhysReg *CSR = TRI->getCalleeSavedRegs(&MF); CSR && *CSR; ++CSR)
BV.set(*CSR);
// Saved CSRs are not pristine.
for (auto &I : getCalleeSavedInfo())
for (MCSubRegIterator S(I.getReg(), TRI, true); S.isValid(); ++S)
BV.reset(*S);
return BV;
}
unsigned MachineFrameInfo::estimateStackSize(const MachineFunction &MF) const {
const TargetFrameLowering *TFI = MF.getSubtarget().getFrameLowering();
const TargetRegisterInfo *RegInfo = MF.getSubtarget().getRegisterInfo();
unsigned MaxAlign = getMaxAlignment();
int Offset = 0;
// This code is very, very similar to PEI::calculateFrameObjectOffsets().
// It really should be refactored to share code. Until then, changes
// should keep in mind that there's tight coupling between the two.
for (int i = getObjectIndexBegin(); i != 0; ++i) {
int FixedOff = -getObjectOffset(i);
if (FixedOff > Offset) Offset = FixedOff;
}
for (unsigned i = 0, e = getObjectIndexEnd(); i != e; ++i) {
if (isDeadObjectIndex(i))
continue;
Offset += getObjectSize(i);
unsigned Align = getObjectAlignment(i);
// Adjust to alignment boundary
Offset = (Offset+Align-1)/Align*Align;
MaxAlign = std::max(Align, MaxAlign);
}
if (adjustsStack() && TFI->hasReservedCallFrame(MF))
Offset += getMaxCallFrameSize();
// Round up the size to a multiple of the alignment. If the function has
// any calls or alloca's, align to the target's StackAlignment value to
// ensure that the callee's frame or the alloca data is suitably aligned;
// otherwise, for leaf functions, align to the TransientStackAlignment
// value.
unsigned StackAlign;
if (adjustsStack() || hasVarSizedObjects() ||
(RegInfo->needsStackRealignment(MF) && getObjectIndexEnd() != 0))
StackAlign = TFI->getStackAlignment();
else
StackAlign = TFI->getTransientStackAlignment();
// If the frame pointer is eliminated, all frame offsets will be relative to
// SP not FP. Align to MaxAlign so this works.
StackAlign = std::max(StackAlign, MaxAlign);
unsigned AlignMask = StackAlign - 1;
Offset = (Offset + AlignMask) & ~uint64_t(AlignMask);
return (unsigned)Offset;
}
void MachineFrameInfo::print(const MachineFunction &MF, raw_ostream &OS) const{
if (Objects.empty()) return;
const TargetFrameLowering *FI = MF.getSubtarget().getFrameLowering();
int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0);
OS << "Frame Objects:\n";
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=" << SO.Size;
OS << ", align=" << SO.Alignment;
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 !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void MachineFrameInfo::dump(const MachineFunction &MF) const {
print(MF, dbgs());
}
#endif
//===----------------------------------------------------------------------===//
// MachineJumpTableInfo implementation
//===----------------------------------------------------------------------===//
/// Return the size of each entry in the jump table.
unsigned MachineJumpTableInfo::getEntrySize(const DataLayout &TD) const {
// The size of a jump table entry is 4 bytes unless the entry is just the
// address of a block, in which case it is the pointer size.
switch (getEntryKind()) {
case MachineJumpTableInfo::EK_BlockAddress:
return TD.getPointerSize();
case MachineJumpTableInfo::EK_GPRel64BlockAddress:
return 8;
case MachineJumpTableInfo::EK_GPRel32BlockAddress:
case MachineJumpTableInfo::EK_LabelDifference32:
case MachineJumpTableInfo::EK_Custom32:
return 4;
case MachineJumpTableInfo::EK_Inline:
return 0;
}
llvm_unreachable("Unknown jump table encoding!");
}
/// Return the alignment of each entry in the jump table.
unsigned MachineJumpTableInfo::getEntryAlignment(const DataLayout &TD) const {
// The alignment of a jump table entry is the alignment of int32 unless the
// entry is just the address of a block, in which case it is the pointer
// alignment.
switch (getEntryKind()) {
case MachineJumpTableInfo::EK_BlockAddress:
return TD.getPointerABIAlignment();
case MachineJumpTableInfo::EK_GPRel64BlockAddress:
return TD.getABIIntegerTypeAlignment(64);
case MachineJumpTableInfo::EK_GPRel32BlockAddress:
case MachineJumpTableInfo::EK_LabelDifference32:
case MachineJumpTableInfo::EK_Custom32:
return TD.getABIIntegerTypeAlignment(32);
case MachineJumpTableInfo::EK_Inline:
return 1;
}
llvm_unreachable("Unknown jump table encoding!");
}
/// Create a new jump table entry in the jump table info.
unsigned MachineJumpTableInfo::createJumpTableIndex(
const std::vector<MachineBasicBlock*> &DestBBs) {
assert(!DestBBs.empty() && "Cannot create an empty jump table!");
JumpTables.push_back(MachineJumpTableEntry(DestBBs));
return JumpTables.size()-1;
}
/// 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)
ReplaceMBBInJumpTable(i, Old, New);
return MadeChange;
}
/// If Old is a target of the jump tables, update the jump table to branch to
/// New instead.
bool MachineJumpTableInfo::ReplaceMBBInJumpTable(unsigned Idx,
MachineBasicBlock *Old,
MachineBasicBlock *New) {
assert(Old != New && "Not making a change?");
bool MadeChange = false;
MachineJumpTableEntry &JTE = JumpTables[Idx];
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(raw_ostream &OS) const {
if (JumpTables.empty()) return;
OS << "Jump Tables:\n";
for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) {
OS << " jt#" << i << ": ";
for (unsigned j = 0, f = JumpTables[i].MBBs.size(); j != f; ++j)
OS << " BB#" << JumpTables[i].MBBs[j]->getNumber();
}
OS << '\n';
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
LLVM_DUMP_METHOD void MachineJumpTableInfo::dump() const { print(dbgs()); }
#endif
//===----------------------------------------------------------------------===//
// MachineConstantPool implementation
//===----------------------------------------------------------------------===//
void MachineConstantPoolValue::anchor() { }
Type *MachineConstantPoolEntry::getType() const {
if (isMachineConstantPoolEntry())
return Val.MachineCPVal->getType();
return Val.ConstVal->getType();
}
bool MachineConstantPoolEntry::needsRelocation() const {
if (isMachineConstantPoolEntry())
return true;
return Val.ConstVal->needsRelocation();
}
SectionKind
MachineConstantPoolEntry::getSectionKind(const DataLayout *DL) const {
if (needsRelocation())
return SectionKind::getReadOnlyWithRel();
switch (DL->getTypeAllocSize(getType())) {
case 4:
return SectionKind::getMergeableConst4();
case 8:
return SectionKind::getMergeableConst8();
case 16:
return SectionKind::getMergeableConst16();
case 32:
return SectionKind::getMergeableConst32();
default:
return SectionKind::getReadOnly();
}
}
MachineConstantPool::~MachineConstantPool() {
for (unsigned i = 0, e = Constants.size(); i != e; ++i)
if (Constants[i].isMachineConstantPoolEntry())
delete Constants[i].Val.MachineCPVal;
for (DenseSet<MachineConstantPoolValue*>::iterator I =
MachineCPVsSharingEntries.begin(), E = MachineCPVsSharingEntries.end();
I != E; ++I)
delete *I;
}
/// Test whether the given two constants can be allocated the same constant pool
/// entry.
static bool CanShareConstantPoolEntry(const Constant *A, const Constant *B,
const DataLayout &DL) {
// Handle the trivial case quickly.
if (A == B) return true;
// If they have the same type but weren't the same constant, quickly
// reject them.
if (A->getType() == B->getType()) return false;
// We can't handle structs or arrays.
if (isa<StructType>(A->getType()) || isa<ArrayType>(A->getType()) ||
isa<StructType>(B->getType()) || isa<ArrayType>(B->getType()))
return false;
// For now, only support constants with the same size.
uint64_t StoreSize = DL.getTypeStoreSize(A->getType());
if (StoreSize != DL.getTypeStoreSize(B->getType()) || StoreSize > 128)
return false;
Type *IntTy = IntegerType::get(A->getContext(), StoreSize*8);
// Try constant folding a bitcast of both instructions to an integer. If we
// get two identical ConstantInt's, then we are good to share them. We use
// the constant folding APIs to do this so that we get the benefit of
// DataLayout.
if (isa<PointerType>(A->getType()))
A = ConstantFoldCastOperand(Instruction::PtrToInt,
const_cast<Constant *>(A), IntTy, DL);
else if (A->getType() != IntTy)
A = ConstantFoldCastOperand(Instruction::BitCast, const_cast<Constant *>(A),
IntTy, DL);
if (isa<PointerType>(B->getType()))
B = ConstantFoldCastOperand(Instruction::PtrToInt,
const_cast<Constant *>(B), IntTy, DL);
else if (B->getType() != IntTy)
B = ConstantFoldCastOperand(Instruction::BitCast, const_cast<Constant *>(B),
IntTy, DL);
return A == B;
}
/// 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(const 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].isMachineConstantPoolEntry() &&
CanShareConstantPoolEntry(Constants[i].Val.ConstVal, C, DL)) {
if ((unsigned)Constants[i].getAlignment() < Alignment)
Constants[i].Alignment = Alignment;
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) {
MachineCPVsSharingEntries.insert(V);
return (unsigned)Idx;
}
Constants.push_back(MachineConstantPoolEntry(V, Alignment));
return Constants.size()-1;
}
void MachineConstantPool::print(raw_ostream &OS) const {
if (Constants.empty()) return;
OS << "Constant Pool:\n";
for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
OS << " cp#" << i << ": ";
if (Constants[i].isMachineConstantPoolEntry())
Constants[i].Val.MachineCPVal->print(OS);
else
Constants[i].Val.ConstVal->printAsOperand(OS, /*PrintType=*/false);
OS << ", align=" << Constants[i].getAlignment();
OS << "\n";
}
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
LLVM_DUMP_METHOD void MachineConstantPool::dump() const { print(dbgs()); }
#endif
Reference in New Issue View Git Blame Copy Permalink