diff options
Diffstat (limited to 'lib/CodeGen/MachineFunction.cpp')
| -rw-r--r-- | lib/CodeGen/MachineFunction.cpp | 173 |
1 files changed, 149 insertions, 24 deletions
diff --git a/lib/CodeGen/MachineFunction.cpp b/lib/CodeGen/MachineFunction.cpp index 91d521185767..04321f329282 100644 --- a/lib/CodeGen/MachineFunction.cpp +++ b/lib/CodeGen/MachineFunction.cpp @@ -14,28 +14,28 @@ //===----------------------------------------------------------------------===// #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/DebugInfo.h" +#include "llvm/IR/DataLayout.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" using namespace llvm; //===----------------------------------------------------------------------===// @@ -58,14 +58,17 @@ MachineFunction::MachineFunction(const Function *F, const TargetMachine &TM, else RegInfo = 0; MFInfo = 0; - FrameInfo = new (Allocator) MachineFrameInfo(*TM.getFrameLowering()); - if (Fn->getFnAttributes().hasAttribute(Attributes::StackAlignment)) + FrameInfo = new (Allocator) MachineFrameInfo(*TM.getFrameLowering(), + TM.Options.RealignStack); + if (Fn->getAttributes().hasAttribute(AttributeSet::FunctionIndex, + Attribute::StackAlignment)) FrameInfo->ensureMaxAlignment(Fn->getAttributes(). - getFnAttributes().getStackAlignment()); + getStackAlignment(AttributeSet::FunctionIndex)); ConstantPool = new (Allocator) MachineConstantPool(TM.getDataLayout()); Alignment = TM.getTargetLowering()->getMinFunctionAlignment(); // FIXME: Shouldn't use pref alignment if explicit alignment is set on Fn. - if (!Fn->getFnAttributes().hasAttribute(Attributes::OptimizeForSize)) + if (!Fn->getAttributes().hasAttribute(AttributeSet::FunctionIndex, + Attribute::OptimizeForSize)) Alignment = std::max(Alignment, TM.getTargetLowering()->getPrefFunctionAlignment()); FunctionNumber = FunctionNum; @@ -73,8 +76,15 @@ MachineFunction::MachineFunction(const Function *F, const TargetMachine &TM, } 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(); @@ -157,7 +167,7 @@ MachineInstr * 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 @@ -172,9 +182,17 @@ MachineFunction::CloneMachineInstr(const MachineInstr *Orig) { /// 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); } @@ -328,13 +346,6 @@ void MachineFunction::print(raw_ostream &OS, SlotIndexes *Indexes) const { } 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) { OS << '\n'; @@ -445,6 +456,70 @@ MCSymbol *MachineFunction::getPICBaseSymbol() const { // MachineFrameInfo implementation //===----------------------------------------------------------------------===// +/// ensureMaxAlignment - Make sure the function is at least Align bytes +/// aligned. +void MachineFrameInfo::ensureMaxAlignment(unsigned Align) { + if (!TFI.isStackRealignable() || !RealignOption) + assert(Align <= TFI.getStackAlignment() && + "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, bool MayNeedSP, const AllocaInst *Alloca) { + assert(Size != 0 && "Cannot allocate zero size stack objects!"); + Alignment = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption, + Alignment, TFI.getStackAlignment()); + Objects.push_back(StackObject(Size, Alignment, 0, false, isSS, MayNeedSP, + Alloca)); + 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(!TFI.isStackRealignable() || !RealignOption, + Alignment, TFI.getStackAlignment()); + CreateStackObject(Size, Alignment, true, false); + 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) { + HasVarSizedObjects = true; + Alignment = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption, + Alignment, TFI.getStackAlignment()); + Objects.push_back(StackObject(0, Alignment, 0, false, false, true, 0)); + 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 @@ -459,6 +534,8 @@ int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset, // object is 16-byte aligned. unsigned StackAlign = TFI.getStackAlignment(); unsigned Align = MinAlign(SPOffset, StackAlign); + Align = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption, + Align, TFI.getStackAlignment()); Objects.insert(Objects.begin(), StackObject(Size, Align, SPOffset, Immutable, /*isSS*/ false, /*NeedSP*/ false, @@ -497,6 +574,54 @@ MachineFrameInfo::getPristineRegs(const MachineBasicBlock *MBB) const { return BV; } +unsigned MachineFrameInfo::estimateStackSize(const MachineFunction &MF) const { + const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering(); + const TargetRegisterInfo *RegInfo = MF.getTarget().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; |