LLVM  14.0.0git
Public Member Functions | List of all members
llvm::SystemZELFFrameLowering Class Reference

#include "Target/SystemZ/SystemZFrameLowering.h"

Inheritance diagram for llvm::SystemZELFFrameLowering:
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Collaboration diagram for llvm::SystemZELFFrameLowering:
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Public Member Functions

 SystemZELFFrameLowering ()
 
bool isFPCloseToIncomingSP () const override
 isFPCloseToIncomingSP - Return true if the frame pointer is close to the incoming stack pointer, false if it is close to the post-prologue stack pointer. More...
 
bool assignCalleeSavedSpillSlots (MachineFunction &MF, const TargetRegisterInfo *TRI, std::vector< CalleeSavedInfo > &CSI) const override
 
void determineCalleeSaves (MachineFunction &MF, BitVector &SavedRegs, RegScavenger *RS) const override
 This method determines which of the registers reported by TargetRegisterInfo::getCalleeSavedRegs() should actually get saved. More...
 
bool spillCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI, ArrayRef< CalleeSavedInfo > CSI, const TargetRegisterInfo *TRI) const override
 spillCalleeSavedRegisters - Issues instruction(s) to spill all callee saved registers and returns true if it isn't possible / profitable to do so by issuing a series of store instructions via storeRegToStackSlot(). More...
 
bool restoreCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBII, MutableArrayRef< CalleeSavedInfo > CSI, const TargetRegisterInfo *TRI) const override
 restoreCalleeSavedRegisters - Issues instruction(s) to restore all callee saved registers and returns true if it isn't possible / profitable to do so by issuing a series of load instructions via loadRegToStackSlot(). More...
 
void processFunctionBeforeFrameFinalized (MachineFunction &MF, RegScavenger *RS) const override
 processFunctionBeforeFrameFinalized - This method is called immediately before the specified function's frame layout (MF.getFrameInfo()) is finalized. More...
 
void emitPrologue (MachineFunction &MF, MachineBasicBlock &MBB) const override
 emitProlog/emitEpilog - These methods insert prolog and epilog code into the function. More...
 
void emitEpilogue (MachineFunction &MF, MachineBasicBlock &MBB) const override
 
void inlineStackProbe (MachineFunction &MF, MachineBasicBlock &PrologMBB) const override
 Replace a StackProbe stub (if any) with the actual probe code inline. More...
 
bool hasFP (const MachineFunction &MF) const override
 hasFP - Return true if the specified function should have a dedicated frame pointer register. More...
 
StackOffset getFrameIndexReference (const MachineFunction &MF, int FI, Register &FrameReg) const override
 getFrameIndexReference - This method should return the base register and offset used to reference a frame index location. More...
 
unsigned getRegSpillOffset (MachineFunction &MF, Register Reg) const
 
bool usePackedStack (MachineFunction &MF) const
 
unsigned getBackchainOffset (MachineFunction &MF) const
 
int getOrCreateFramePointerSaveIndex (MachineFunction &MF) const
 
- Public Member Functions inherited from llvm::SystemZFrameLowering
 SystemZFrameLowering (StackDirection D, Align StackAl, int LAO, Align TransAl, bool StackReal)
 
bool hasReservedCallFrame (const MachineFunction &MF) const override
 hasReservedCallFrame - Under normal circumstances, when a frame pointer is not required, we reserve argument space for call sites in the function immediately on entry to the current function. More...
 
MachineBasicBlock::iterator eliminateCallFramePseudoInstr (MachineFunction &MF, MachineBasicBlock &MBB, MachineBasicBlock::iterator MI) const override
 This method is called during prolog/epilog code insertion to eliminate call frame setup and destroy pseudo instructions (but only if the Target is using them). More...
 
- Public Member Functions inherited from llvm::TargetFrameLowering
 TargetFrameLowering (StackDirection D, Align StackAl, int LAO, Align TransAl=Align(1), bool StackReal=true)
 
virtual ~TargetFrameLowering ()
 
StackDirection getStackGrowthDirection () const
 getStackGrowthDirection - Return the direction the stack grows More...
 
unsigned getStackAlignment () const
 getStackAlignment - This method returns the number of bytes to which the stack pointer must be aligned on entry to a function. More...
 
Align getStackAlign () const
 getStackAlignment - This method returns the number of bytes to which the stack pointer must be aligned on entry to a function. More...
 
int alignSPAdjust (int SPAdj) const
 alignSPAdjust - This method aligns the stack adjustment to the correct alignment. More...
 
Align getTransientStackAlign () const
 getTransientStackAlignment - This method returns the number of bytes to which the stack pointer must be aligned at all times, even between calls. More...
 
bool isStackRealignable () const
 isStackRealignable - This method returns whether the stack can be realigned. More...
 
virtual unsigned getStackAlignmentSkew (const MachineFunction &MF) const
 Return the skew that has to be applied to stack alignment under certain conditions (e.g. More...
 
virtual bool isStackIdSafeForLocalArea (unsigned StackId) const
 This method returns whether or not it is safe for an object with the given stack id to be bundled into the local area. More...
 
int getOffsetOfLocalArea () const
 getOffsetOfLocalArea - This method returns the offset of the local area from the stack pointer on entrance to a function. More...
 
virtual bool assignCalleeSavedSpillSlots (MachineFunction &MF, const TargetRegisterInfo *TRI, std::vector< CalleeSavedInfo > &CSI, unsigned &MinCSFrameIndex, unsigned &MaxCSFrameIndex) const
 assignCalleeSavedSpillSlots - Allows target to override spill slot assignment logic. More...
 
virtual const SpillSlotgetCalleeSavedSpillSlots (unsigned &NumEntries) const
 getCalleeSavedSpillSlots - This method returns a pointer to an array of pairs, that contains an entry for each callee saved register that must be spilled to a particular stack location if it is spilled. More...
 
virtual bool targetHandlesStackFrameRounding () const
 targetHandlesStackFrameRounding - Returns true if the target is responsible for rounding up the stack frame (probably at emitPrologue time). More...
 
virtual bool enableShrinkWrapping (const MachineFunction &MF) const
 Returns true if the target will correctly handle shrink wrapping. More...
 
virtual bool enableStackSlotScavenging (const MachineFunction &MF) const
 Returns true if the stack slot holes in the fixed and callee-save stack area should be used when allocating other stack locations to reduce stack size. More...
 
virtual bool enableCalleeSaveSkip (const MachineFunction &MF) const
 Returns true if the target can safely skip saving callee-saved registers for noreturn nounwind functions. More...
 
virtual void emitCalleeSavedFrameMoves (MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI) const
 With basic block sections, emit callee saved frame moves for basic blocks that are in a different section. More...
 
virtual void adjustForSegmentedStacks (MachineFunction &MF, MachineBasicBlock &PrologueMBB) const
 Adjust the prologue to have the function use segmented stacks. More...
 
virtual void adjustForHiPEPrologue (MachineFunction &MF, MachineBasicBlock &PrologueMBB) const
 Adjust the prologue to add Erlang Run-Time System (ERTS) specific code in the assembly prologue to explicitly handle the stack. More...
 
virtual bool keepFramePointer (const MachineFunction &MF) const
 Return true if the target wants to keep the frame pointer regardless of the function attribute "frame-pointer". More...
 
virtual bool canSimplifyCallFramePseudos (const MachineFunction &MF) const
 canSimplifyCallFramePseudos - When possible, it's best to simplify the call frame pseudo ops before doing frame index elimination. More...
 
virtual bool needsFrameIndexResolution (const MachineFunction &MF) const
 
virtual StackOffset getFrameIndexReferencePreferSP (const MachineFunction &MF, int FI, Register &FrameReg, bool IgnoreSPUpdates) const
 Same as getFrameIndexReference, except that the stack pointer (as opposed to the frame pointer) will be the preferred value for FrameReg. More...
 
virtual StackOffset getNonLocalFrameIndexReference (const MachineFunction &MF, int FI) const
 getNonLocalFrameIndexReference - This method returns the offset used to reference a frame index location. More...
 
virtual void getCalleeSaves (const MachineFunction &MF, BitVector &SavedRegs) const
 Returns the callee-saved registers as computed by determineCalleeSaves in the BitVector SavedRegs. More...
 
virtual void processFunctionBeforeFrameIndicesReplaced (MachineFunction &MF, RegScavenger *RS=nullptr) const
 processFunctionBeforeFrameIndicesReplaced - This method is called immediately before MO_FrameIndex operands are eliminated, but after the frame is finalized. More...
 
virtual unsigned getWinEHParentFrameOffset (const MachineFunction &MF) const
 
virtual void orderFrameObjects (const MachineFunction &MF, SmallVectorImpl< int > &objectsToAllocate) const
 Order the symbols in the local stack frame. More...
 
virtual bool canUseAsPrologue (const MachineBasicBlock &MBB) const
 Check whether or not the given MBB can be used as a prologue for the target. More...
 
virtual bool canUseAsEpilogue (const MachineBasicBlock &MBB) const
 Check whether or not the given MBB can be used as a epilogue for the target. More...
 
virtual TargetStackID::Value getStackIDForScalableVectors () const
 Returns the StackID that scalable vectors should be associated with. More...
 
virtual bool isSupportedStackID (TargetStackID::Value ID) const
 
virtual bool isProfitableForNoCSROpt (const Function &F) const
 Check if the no-CSR optimisation is profitable for the given function. More...
 
virtual int getInitialCFAOffset (const MachineFunction &MF) const
 Return initial CFA offset value i.e. More...
 
virtual Register getInitialCFARegister (const MachineFunction &MF) const
 Return initial CFA register value i.e. More...
 
virtual DwarfFrameBase getDwarfFrameBase (const MachineFunction &MF) const
 Return the frame base information to be encoded in the DWARF subprogram debug info. More...
 

Additional Inherited Members

- Public Types inherited from llvm::TargetFrameLowering
enum  StackDirection { StackGrowsUp, StackGrowsDown }
 
- Static Public Member Functions inherited from llvm::SystemZFrameLowering
static std::unique_ptr< SystemZFrameLoweringcreate (const SystemZSubtarget &STI)
 
- Static Public Member Functions inherited from llvm::TargetFrameLowering
static bool isSafeForNoCSROpt (const Function &F)
 Check if given function is safe for not having callee saved registers. More...
 

Detailed Description

Definition at line 39 of file SystemZFrameLowering.h.

Constructor & Destructor Documentation

◆ SystemZELFFrameLowering()

SystemZELFFrameLowering::SystemZELFFrameLowering ( )

Member Function Documentation

◆ assignCalleeSavedSpillSlots()

bool SystemZELFFrameLowering::assignCalleeSavedSpillSlots ( MachineFunction MF,
const TargetRegisterInfo TRI,
std::vector< CalleeSavedInfo > &  CSI 
) const
overridevirtual

◆ determineCalleeSaves()

void SystemZELFFrameLowering::determineCalleeSaves ( MachineFunction MF,
BitVector SavedRegs,
RegScavenger RS 
) const
overridevirtual

This method determines which of the registers reported by TargetRegisterInfo::getCalleeSavedRegs() should actually get saved.

The default implementation checks populates the SavedRegs bitset with all registers which are modified in the function, targets may override this function to save additional registers. This method also sets up the register scavenger ensuring there is a free register or a frameindex available. This method should not be called by any passes outside of PEI, because it may change state passed in by MF and RS. The preferred interface outside PEI is getCalleeSaves.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 159 of file SystemZFrameLowering.cpp.

References contains(), llvm::TargetFrameLowering::determineCalleeSaves(), llvm::SystemZ::ELFArgGPRs, llvm::SystemZ::ELFNumArgGPRs, llvm::TargetRegisterInfo::getCalleeSavedRegs(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getFunction(), llvm::MachineFunction::getInfo(), llvm::MachineFunction::getLandingPads(), llvm::TargetSubtargetInfo::getRegisterInfo(), llvm::MachineFunction::getSubtarget(), llvm::SystemZMachineFunctionInfo::getVarArgsFirstGPR(), llvm::MachineFrameInfo::hasCalls(), hasFP(), I, llvm::Function::isVarArg(), Reg, llvm::BitVector::set(), llvm::BitVector::test(), and TRI.

◆ emitEpilogue()

void SystemZELFFrameLowering::emitEpilogue ( MachineFunction MF,
MachineBasicBlock MBB 
) const
overridevirtual

◆ emitPrologue()

void SystemZELFFrameLowering::emitPrologue ( MachineFunction MF,
MachineBasicBlock MBB 
) const
overridevirtual

emitProlog/emitEpilog - These methods insert prolog and epilog code into the function.

Implements llvm::TargetFrameLowering.

Definition at line 456 of file SystemZFrameLowering.cpp.

References llvm::MachineInstrBuilder::addCFIIndex(), llvm::MachineFunction::addFrameInst(), llvm::MachineInstrBuilder::addImm(), llvm::MachineInstrBuilder::addReg(), assert(), llvm::MachineBasicBlock::begin(), buildCFAOffs(), buildDefCFAReg(), llvm::BuildMI(), contains(), llvm::MCCFIInstruction::createOffset(), llvm::RegState::Define, DL, llvm::drop_begin(), llvm::numbers::e, llvm::SystemZMC::ELFCallFrameSize, llvm::SystemZMC::ELFCFAOffsetFromInitialSP, emitIncrement(), llvm::MachineBasicBlock::end(), llvm::MachineFunction::front(), getBackchainOffset(), llvm::MachineFrameInfo::getCalleeSavedInfo(), llvm::Function::getCallingConv(), llvm::MachineModuleInfo::getContext(), llvm::StackOffset::getFixed(), getFrameIndexReference(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getFunction(), llvm::MachineFunction::getInfo(), llvm::SystemZSubtarget::getInstrInfo(), llvm::MachineFunction::getMMI(), llvm::MachineFrameInfo::getObjectIndexEnd(), llvm::MachineFrameInfo::getObjectOffset(), llvm::MCContext::getRegisterInfo(), llvm::SystemZMachineFunctionInfo::getSpillGPRRegs(), llvm::MachineFrameInfo::getStackSize(), llvm::MachineFunction::getSubtarget(), llvm::TargetSubtargetInfo::getTargetLowering(), llvm::SystemZSubtarget::getTargetLowering(), llvm::CallingConv::GHC, llvm::SystemZ::GPRRegs::GPROffset, llvm::MachineFrameInfo::hasCalls(), llvm::Function::hasFnAttribute(), hasFP(), llvm::TargetLoweringBase::hasInlineStackProbe(), i, llvm::MachineFrameInfo::isDeadObjectIndex(), llvm::RegState::Kill, llvm_unreachable, llvm::SystemZ::GPRRegs::LowGPR, MBB, MBBI, MRI, Offset, Reg, llvm::report_fatal_error(), llvm::MachineFrameInfo::setStackSize(), and llvm::AArch64ISD::STG.

◆ getBackchainOffset()

unsigned llvm::SystemZELFFrameLowering::getBackchainOffset ( MachineFunction MF) const
inline

◆ getFrameIndexReference()

StackOffset SystemZELFFrameLowering::getFrameIndexReference ( const MachineFunction MF,
int  FI,
Register FrameReg 
) const
overridevirtual

getFrameIndexReference - This method should return the base register and offset used to reference a frame index location.

Returns the displacement from the frame register to the stack frame of the specified index, along with the frame register used (in output arg FrameReg).

The offset is returned directly, and the base register is returned via FrameReg.

This is the default implementation which is overridden for some targets.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 771 of file SystemZFrameLowering.cpp.

References llvm::SystemZMC::ELFCallFrameSize, llvm::StackOffset::getFixed(), llvm::TargetFrameLowering::getFrameIndexReference(), and Offset.

Referenced by emitPrologue().

◆ getOrCreateFramePointerSaveIndex()

int SystemZELFFrameLowering::getOrCreateFramePointerSaveIndex ( MachineFunction MF) const

◆ getRegSpillOffset()

unsigned SystemZELFFrameLowering::getRegSpillOffset ( MachineFunction MF,
Register  Reg 
) const

◆ hasFP()

bool SystemZELFFrameLowering::hasFP ( const MachineFunction MF) const
overridevirtual

hasFP - Return true if the specified function should have a dedicated frame pointer register.

For most targets this is true only if the function has variable sized allocas or if frame pointer elimination is disabled.

Implements llvm::TargetFrameLowering.

Definition at line 765 of file SystemZFrameLowering.cpp.

References llvm::TargetOptions::DisableFramePointerElim(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getInfo(), llvm::SystemZMachineFunctionInfo::getManipulatesSP(), llvm::MachineFunction::getTarget(), llvm::MachineFrameInfo::hasVarSizedObjects(), and llvm::TargetMachine::Options.

Referenced by determineCalleeSaves(), emitPrologue(), and restoreCalleeSavedRegisters().

◆ inlineStackProbe()

void SystemZELFFrameLowering::inlineStackProbe ( MachineFunction MF,
MachineBasicBlock PrologueMBB 
) const
overridevirtual

◆ isFPCloseToIncomingSP()

bool llvm::SystemZELFFrameLowering::isFPCloseToIncomingSP ( ) const
inlineoverridevirtual

isFPCloseToIncomingSP - Return true if the frame pointer is close to the incoming stack pointer, false if it is close to the post-prologue stack pointer.

Reimplemented from llvm::SystemZFrameLowering.

Definition at line 46 of file SystemZFrameLowering.h.

◆ processFunctionBeforeFrameFinalized()

void SystemZELFFrameLowering::processFunctionBeforeFrameFinalized ( MachineFunction MF,
RegScavenger RS 
) const
overridevirtual

◆ restoreCalleeSavedRegisters()

bool SystemZELFFrameLowering::restoreCalleeSavedRegisters ( MachineBasicBlock MBB,
MachineBasicBlock::iterator  MI,
MutableArrayRef< CalleeSavedInfo CSI,
const TargetRegisterInfo TRI 
) const
overridevirtual

restoreCalleeSavedRegisters - Issues instruction(s) to restore all callee saved registers and returns true if it isn't possible / profitable to do so by issuing a series of load instructions via loadRegToStackSlot().

If it returns true, and any of the registers in CSI is not restored, it sets the corresponding Restored flag in CSI to false. Returns false otherwise.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 303 of file SystemZFrameLowering.cpp.

References llvm::MachineInstrBuilder::addImm(), llvm::MachineInstrBuilder::addReg(), assert(), llvm::BuildMI(), contains(), llvm::RegState::Define, DL, E, llvm::ArrayRef< T >::empty(), llvm::MachineBasicBlock::end(), llvm::MachineFunction::getInfo(), llvm::TargetSubtargetInfo::getInstrInfo(), llvm::MachineBasicBlock::getParent(), llvm::SystemZMachineFunctionInfo::getRestoreGPRRegs(), llvm::MachineFunction::getSubtarget(), llvm::SystemZ::GPRRegs::GPROffset, hasFP(), llvm::SystemZ::GPRRegs::HighGPR, I, llvm::RegState::ImplicitDefine, llvm::HexagonInstrInfo::loadRegFromStackSlot(), llvm::SystemZ::GPRRegs::LowGPR, MBB, MBBI, Reg, llvm::ArrayRef< T >::size(), TII, and TRI.

◆ spillCalleeSavedRegisters()

bool SystemZELFFrameLowering::spillCalleeSavedRegisters ( MachineBasicBlock MBB,
MachineBasicBlock::iterator  MI,
ArrayRef< CalleeSavedInfo CSI,
const TargetRegisterInfo TRI 
) const
overridevirtual

◆ usePackedStack()

bool SystemZELFFrameLowering::usePackedStack ( MachineFunction MF) const

The documentation for this class was generated from the following files: