//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/MachineFunction.h"
-#include "llvm/DebugInfo.h"
-#include "llvm/Function.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/CodeGen/MachineConstantPool.h"
-#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineFrameInfo.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/IR/DataLayout.h"
+#include "llvm/IR/DebugInfo.h"
+#include "llvm/IR/Function.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
-#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Support/Debug.h"
-#include "llvm/DataLayout.h"
-#include "llvm/Target/TargetLowering.h"
-#include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetFrameLowering.h"
-#include "llvm/ADT/SmallString.h"
-#include "llvm/ADT/STLExtras.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"
+
//===----------------------------------------------------------------------===//
// MachineFunction implementation
//===----------------------------------------------------------------------===//
}
MachineFunction::MachineFunction(const Function *F, const TargetMachine &TM,
- unsigned FunctionNum, MachineModuleInfo &mmi,
- GCModuleInfo* gmi)
- : Fn(F), Target(TM), Ctx(mmi.getContext()), MMI(mmi), GMI(gmi) {
- if (TM.getRegisterInfo())
- RegInfo = new (Allocator) MachineRegisterInfo(*TM.getRegisterInfo());
+ unsigned FunctionNum, MachineModuleInfo &mmi)
+ : Fn(F), Target(TM), STI(TM.getSubtargetImpl()), Ctx(mmi.getContext()),
+ MMI(mmi) {
+ if (STI->getRegisterInfo())
+ RegInfo = new (Allocator) MachineRegisterInfo(this);
else
- RegInfo = 0;
- MFInfo = 0;
- FrameInfo = new (Allocator) MachineFrameInfo(*TM.getFrameLowering());
- if (Fn->getFnAttributes().hasStackAlignmentAttr())
+ RegInfo = nullptr;
+
+ MFInfo = nullptr;
+ FrameInfo = new (Allocator)
+ MachineFrameInfo(STI->getFrameLowering()->getStackAlignment(),
+ STI->getFrameLowering()->isStackRealignable(),
+ !F->hasFnAttribute("no-realign-stack"));
+
+ if (Fn->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
+ Attribute::StackAlignment))
FrameInfo->ensureMaxAlignment(Fn->getAttributes().
- getFnAttributes().getStackAlignment());
- ConstantPool = new (Allocator) MachineConstantPool(TM.getDataLayout());
- Alignment = TM.getTargetLowering()->getMinFunctionAlignment();
+ getStackAlignment(AttributeSet::FunctionIndex));
+
+ ConstantPool = new (Allocator) MachineConstantPool(TM);
+ Alignment = STI->getTargetLowering()->getMinFunctionAlignment();
+
// FIXME: Shouldn't use pref alignment if explicit alignment is set on Fn.
- if (!Fn->getFnAttributes().hasOptimizeForSizeAttr())
+ if (!Fn->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
+ Attribute::OptimizeForSize))
Alignment = std::max(Alignment,
- TM.getTargetLowering()->getPrefFunctionAlignment());
+ STI->getTargetLowering()->getPrefFunctionAlignment());
+
FunctionNumber = FunctionNum;
- JumpTableInfo = 0;
+ JumpTableInfo = nullptr;
}
MachineFunction::~MachineFunction() {
- BasicBlocks.clear();
+ // 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();
return JumpTableInfo;
}
+/// Should we be emitting segmented stack stuff for the function
+bool MachineFunction::shouldSplitStack() {
+ return getFunction()->hasFnAttribute("split-stack");
+}
+
/// 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
void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) {
if (empty()) { MBBNumbering.clear(); return; }
MachineFunction::iterator MBBI, E = end();
- if (MBB == 0)
+ if (MBB == nullptr)
MBBI = begin();
else
MBBI = MBB;
// Figure out the block number this should have.
unsigned BlockNo = 0;
if (MBBI != begin())
- BlockNo = prior(MBBI)->getNumber()+1;
+ BlockNo = std::prev(MBBI)->getNumber() + 1;
for (; MBBI != E; ++MBBI, ++BlockNo) {
if (MBBI->getNumber() != (int)BlockNo) {
if (MBBI->getNumber() != -1) {
assert(MBBNumbering[MBBI->getNumber()] == &*MBBI &&
"MBB number mismatch!");
- MBBNumbering[MBBI->getNumber()] = 0;
+ MBBNumbering[MBBI->getNumber()] = nullptr;
}
// If BlockNo is already taken, set that block's number to -1.
MachineFunction::CreateMachineInstr(const MCInstrDesc &MCID,
DebugLoc DL, bool NoImp) {
return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
- MachineInstr(MCID, DL, NoImp);
+ MachineInstr(*this, MCID, DL, NoImp);
}
/// CloneMachineInstr - Create a new MachineInstr which is a copy of the
/// DeleteMachineInstr - Delete the given MachineInstr.
///
+/// This function also serves as the MachineInstr destructor - the real
+/// ~MachineInstr() destructor must be empty.
void
MachineFunction::DeleteMachineInstr(MachineInstr *MI) {
- MI->~MachineInstr();
+ // 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);
}
MachineMemOperand *
MachineFunction::getMachineMemOperand(MachinePointerInfo PtrInfo, unsigned f,
uint64_t s, unsigned base_alignment,
- const MDNode *TBAAInfo,
+ const AAMDNodes &AAInfo,
const MDNode *Ranges) {
return new (Allocator) MachineMemOperand(PtrInfo, f, s, base_alignment,
- TBAAInfo, Ranges);
+ 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->getValue(),
+ MachineMemOperand(MachinePointerInfo(MMO->getPseudoValue(),
MMO->getOffset()+Offset),
MMO->getFlags(), Size,
- MMO->getBaseAlignment(), 0);
+ MMO->getBaseAlignment());
}
MachineInstr::mmo_iterator
getMachineMemOperand((*I)->getPointerInfo(),
(*I)->getFlags() & ~MachineMemOperand::MOStore,
(*I)->getSize(), (*I)->getBaseAlignment(),
- (*I)->getTBAAInfo());
+ (*I)->getAAInfo());
Result[Index] = JustLoad;
}
++Index;
getMachineMemOperand((*I)->getPointerInfo(),
(*I)->getFlags() & ~MachineMemOperand::MOLoad,
(*I)->getSize(), (*I)->getBaseAlignment(),
- (*I)->getTBAAInfo());
+ (*I)->getAAInfo());
Result[Index] = JustStore;
}
++Index;
// Print Constant Pool
ConstantPool->print(OS);
- const TargetRegisterInfo *TRI = getTarget().getRegisterInfo();
+ const TargetRegisterInfo *TRI = getSubtarget().getRegisterInfo();
if (RegInfo && !RegInfo->livein_empty()) {
OS << "Function Live Ins: ";
OS << PrintReg(I->first, TRI);
if (I->second)
OS << " in " << PrintReg(I->second, TRI);
- if (llvm::next(I) != E)
+ if (std::next(I) != E)
OS << ", ";
}
OS << '\n';
}
- if (RegInfo && !RegInfo->liveout_empty()) {
- OS << "Function Live Outs:";
- for (MachineRegisterInfo::liveout_iterator
- I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I)
- OS << ' ' << PrintReg(*I, TRI);
- OS << '\n';
- }
- for (const_iterator BB = begin(), E = end(); BB != E; ++BB) {
+ for (const auto &BB : *this) {
OS << '\n';
- BB->print(OS, Indexes);
+ BB.print(OS, Indexes);
}
OS << "\n# End machine code for function " << getName() << ".\n\n";
MachineRegisterInfo &MRI = getRegInfo();
unsigned VReg = MRI.getLiveInVirtReg(PReg);
if (VReg) {
- assert(MRI.getRegClass(VReg) == RC && "Register class mismatch!");
+ 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);
/// getJTISymbol - 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,
+MCSymbol *MachineFunction::getJTISymbol(unsigned JTI, MCContext &Ctx,
bool isLinkerPrivate) const {
+ const DataLayout *DL = getSubtarget().getDataLayout();
assert(JumpTableInfo && "No jump tables");
assert(JTI < JumpTableInfo->getJumpTables().size() && "Invalid JTI!");
- const MCAsmInfo &MAI = *getTarget().getMCAsmInfo();
- const char *Prefix = isLinkerPrivate ? MAI.getLinkerPrivateGlobalPrefix() :
- MAI.getPrivateGlobalPrefix();
+ const char *Prefix = isLinkerPrivate ? DL->getLinkerPrivateGlobalPrefix() :
+ DL->getPrivateGlobalPrefix();
SmallString<60> Name;
raw_svector_ostream(Name)
<< Prefix << "JTI" << getFunctionNumber() << '_' << JTI;
/// getPICBaseSymbol - Return a function-local symbol to represent the PIC
/// base.
MCSymbol *MachineFunction::getPICBaseSymbol() const {
- const MCAsmInfo &MAI = *Target.getMCAsmInfo();
- return Ctx.GetOrCreateSymbol(Twine(MAI.getPrivateGlobalPrefix())+
+ const DataLayout *DL = getSubtarget().getDataLayout();
+ return Ctx.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix())+
Twine(getFunctionNumber())+"$pb");
}
// MachineFrameInfo implementation
//===----------------------------------------------------------------------===//
+/// ensureMaxAlignment - Make sure the function is at least Align bytes
+/// aligned.
+void MachineFrameInfo::ensureMaxAlignment(unsigned Align) {
+ if (!StackRealignable || !RealignOption)
+ assert(Align <= StackAlignment &&
+ "For targets without stack realignment, Align is out of limit!");
+ if (MaxAlignment < Align) MaxAlignment = Align;
+}
+
+/// clampStackAlignment - 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;
+}
+
+/// CreateStackObject - 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 || !RealignOption,
+ 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;
+}
+
+/// CreateSpillStackObject - 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 || !RealignOption,
+ Alignment, StackAlignment);
+ CreateStackObject(Size, Alignment, true);
+ int Index = (int)Objects.size() - NumFixedObjects - 1;
+ ensureMaxAlignment(Alignment);
+ return Index;
+}
+
+/// CreateVariableSizedObject - 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 || !RealignOption,
+ Alignment, StackAlignment);
+ Objects.push_back(StackObject(0, Alignment, 0, false, false, Alloca, true));
+ ensureMaxAlignment(Alignment);
+ return (int)Objects.size()-NumFixedObjects-1;
+}
+
/// 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) {
+ 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.
- unsigned StackAlign = TFI.getStackAlignment();
- unsigned Align = MinAlign(SPOffset, StackAlign);
+ unsigned Align = MinAlign(SPOffset, StackAlignment);
+ Align = clampStackAlignment(!StackRealignable || !RealignOption, Align,
+ StackAlignment);
Objects.insert(Objects.begin(), StackObject(Size, Align, SPOffset, Immutable,
/*isSS*/ false,
- /*NeedSP*/ false,
- /*Alloca*/ 0));
+ /*Alloca*/ nullptr, isAliased));
return -++NumFixedObjects;
}
+/// CreateFixedSpillStackObject - 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, StackAlignment);
+ Align = clampStackAlignment(!StackRealignable || !RealignOption, Align,
+ StackAlignment);
+ Objects.insert(Objects.begin(), StackObject(Size, Align, SPOffset,
+ /*Immutable*/ true,
+ /*isSS*/ true,
+ /*Alloca*/ nullptr,
+ /*isAliased*/ false));
+ return -++NumFixedObjects;
+}
BitVector
MachineFrameInfo::getPristineRegs(const MachineBasicBlock *MBB) const {
const MachineFunction *MF = MBB->getParent();
assert(MF && "MBB must be part of a MachineFunction");
const TargetMachine &TM = MF->getTarget();
- const TargetRegisterInfo *TRI = TM.getRegisterInfo();
+ const TargetRegisterInfo *TRI = TM.getSubtargetImpl()->getRegisterInfo();
BitVector BV(TRI->getNumRegs());
// Before CSI is calculated, no registers are considered pristine. They can be
if (!isCalleeSavedInfoValid())
return BV;
- for (const uint16_t *CSR = TRI->getCalleeSavedRegs(MF); CSR && *CSR; ++CSR)
+ for (const MCPhysReg *CSR = TRI->getCalleeSavedRegs(MF); CSR && *CSR; ++CSR)
BV.set(*CSR);
// The entry MBB always has all CSRs pristine.
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.getTarget().getFrameLowering();
+ const TargetFrameLowering *FI = MF.getSubtarget().getFrameLowering();
int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0);
OS << "Frame Objects:\n";
void MachineConstantPoolValue::anchor() { }
+const DataLayout *MachineConstantPool::getDataLayout() const {
+ return TM.getSubtargetImpl()->getDataLayout();
+}
+
Type *MachineConstantPoolEntry::getType() const {
if (isMachineConstantPoolEntry())
return Val.MachineCPVal->getType();
return Val.ConstVal->getRelocationInfo();
}
+SectionKind
+MachineConstantPoolEntry::getSectionKind(const DataLayout *DL) const {
+ SectionKind Kind;
+ switch (getRelocationInfo()) {
+ default:
+ llvm_unreachable("Unknown section kind");
+ case 2:
+ Kind = SectionKind::getReadOnlyWithRel();
+ break;
+ case 1:
+ Kind = SectionKind::getReadOnlyWithRelLocal();
+ break;
+ case 0:
+ switch (DL->getTypeAllocSize(getType())) {
+ case 4:
+ Kind = SectionKind::getMergeableConst4();
+ break;
+ case 8:
+ Kind = SectionKind::getMergeableConst8();
+ break;
+ case 16:
+ Kind = SectionKind::getMergeableConst16();
+ break;
+ default:
+ Kind = SectionKind::getMergeableConst();
+ break;
+ }
+ }
+ return Kind;
+}
+
MachineConstantPool::~MachineConstantPool() {
for (unsigned i = 0, e = Constants.size(); i != e; ++i)
if (Constants[i].isMachineConstantPoolEntry())
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 = TD->getTypeStoreSize(A->getType());
- if (StoreSize != TD->getTypeStoreSize(B->getType()) ||
- StoreSize > 128)
+ if (StoreSize != TD->getTypeStoreSize(B->getType()) || StoreSize > 128)
return false;
Type *IntTy = IntegerType::get(A->getContext(), StoreSize*8);
/// an existing one. User must specify the log2 of the minimum required
/// alignment for the object.
///
-unsigned MachineConstantPool::getConstantPoolIndex(const Constant *C,
+unsigned MachineConstantPool::getConstantPoolIndex(const Constant *C,
unsigned Alignment) {
assert(Alignment && "Alignment must be specified!");
if (Alignment > PoolAlignment) PoolAlignment = Alignment;
// 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, TD)) {
+ CanShareConstantPoolEntry(Constants[i].Val.ConstVal, C,
+ getDataLayout())) {
if ((unsigned)Constants[i].getAlignment() < Alignment)
Constants[i].Alignment = Alignment;
return i;
if (Constants[i].isMachineConstantPoolEntry())
Constants[i].Val.MachineCPVal->print(OS);
else
- OS << *(const Value*)Constants[i].Val.ConstVal;
+ Constants[i].Val.ConstVal->printAsOperand(OS, /*PrintType=*/false);
OS << ", align=" << Constants[i].getAlignment();
OS << "\n";
}
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