#include "Target/Xtensa/XtensaFrameLowering.h"
Public Member Functions | |
| XtensaFrameLowering (const XtensaSubtarget &STI) | |
| bool | hasFP (const MachineFunction &MF) const override |
| hasFP - Return true if the specified function should have a dedicated frame pointer register. | |
| void | emitPrologue (MachineFunction &, MachineBasicBlock &) const override |
| emitProlog/emitEpilog - These methods insert prolog and epilog code into the function. | |
| void | emitEpilogue (MachineFunction &MF, MachineBasicBlock &MBB) const override |
| MachineBasicBlock::iterator | eliminateCallFramePseudoInstr (MachineFunction &MF, MachineBasicBlock &MBB, MachineBasicBlock::iterator I) 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). | |
| bool | spillCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, 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(). | |
| bool | restoreCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, 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(). | |
| 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. | |
| 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. | |
 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 | |
| unsigned | getStackAlignment () const |
| getStackAlignment - This method returns the number of bytes to which the stack pointer must be aligned on entry to a function. | |
| Align | getStackAlign () const |
| getStackAlignment - This method returns the number of bytes to which the stack pointer must be aligned on entry to a function. | |
| virtual uint64_t | getStackThreshold () const |
| getStackThreshold - Return the maximum stack size | |
| int | alignSPAdjust (int SPAdj) const |
| alignSPAdjust - This method aligns the stack adjustment to the correct alignment. | |
| 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. | |
| bool | isStackRealignable () const |
| isStackRealignable - This method returns whether the stack can be realigned. | |
| 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. | |
| int | getOffsetOfLocalArea () const |
| getOffsetOfLocalArea - This method returns the offset of the local area from the stack pointer on entrance to a function. | |
| virtual bool | allocateScavengingFrameIndexesNearIncomingSP (const MachineFunction &MF) const |
| Control the placement of special register scavenging spill slots when allocating a stack frame. | |
| 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. | |
| virtual bool | assignCalleeSavedSpillSlots (MachineFunction &MF, const TargetRegisterInfo *TRI, std::vector< CalleeSavedInfo > &CSI) const |
| virtual const SpillSlot * | getCalleeSavedSpillSlots (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. | |
| virtual bool | targetHandlesStackFrameRounding () const |
| targetHandlesStackFrameRounding - Returns true if the target is responsible for rounding up the stack frame (probably at emitPrologue time). | |
| virtual bool | enableShrinkWrapping (const MachineFunction &MF) const |
| Returns true if the target will correctly handle shrink wrapping. | |
| 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. | |
| virtual bool | enableCalleeSaveSkip (const MachineFunction &MF) const |
| Returns true if the target can safely skip saving callee-saved registers for noreturn nounwind functions. | |
| virtual void | emitPrologue (MachineFunction &MF, MachineBasicBlock &MBB) const =0 |
| emitProlog/emitEpilog - These methods insert prolog and epilog code into the function. | |
| virtual void | emitEpilogue (MachineFunction &MF, MachineBasicBlock &MBB) const =0 |
| virtual void | emitZeroCallUsedRegs (BitVector RegsToZero, MachineBasicBlock &MBB) const |
| emitZeroCallUsedRegs - Zeros out call used registers. | |
| virtual void | emitCalleeSavedFrameMovesFullCFA (MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI) const |
| With basic block sections, emit callee saved frame moves for basic blocks that are in a different section. | |
| virtual bool | enableCFIFixup (MachineFunction &MF) const |
| Returns true if we may need to fix the unwind information for the function. | |
| virtual void | resetCFIToInitialState (MachineBasicBlock &MBB) const |
| Emit CFI instructions that recreate the state of the unwind information upon fucntion entry. | |
| virtual void | inlineStackProbe (MachineFunction &MF, MachineBasicBlock &PrologueMBB) const |
| Replace a StackProbe stub (if any) with the actual probe code inline. | |
| virtual bool | stackProbeFunctionModifiesSP () const |
| Does the stack probe function call return with a modified stack pointer? | |
| virtual void | adjustForSegmentedStacks (MachineFunction &MF, MachineBasicBlock &PrologueMBB) const |
| Adjust the prologue to have the function use segmented stacks. | |
| 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. | |
| virtual bool | spillCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, ArrayRef< CalleeSavedInfo > CSI, const TargetRegisterInfo *TRI) const |
| 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(). | |
| virtual bool | restoreCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, MutableArrayRef< CalleeSavedInfo > CSI, const TargetRegisterInfo *TRI) const |
| 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(). | |
| 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". | |
| virtual bool | hasFP (const MachineFunction &MF) const =0 |
| hasFP - Return true if the specified function should have a dedicated frame pointer register. | |
| virtual bool | hasReservedCallFrame (const MachineFunction &MF) const |
| 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. | |
| 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. | |
| virtual bool | needsFrameIndexResolution (const MachineFunction &MF) const |
| virtual StackOffset | getFrameIndexReference (const MachineFunction &MF, int FI, Register &FrameReg) const |
| getFrameIndexReference - This method should return the base register and offset used to reference a frame index location. | |
| 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. | |
| virtual StackOffset | getNonLocalFrameIndexReference (const MachineFunction &MF, int FI) const |
| getNonLocalFrameIndexReference - This method returns the offset used to reference a frame index location. | |
| virtual StackOffset | getFrameIndexReferenceFromSP (const MachineFunction &MF, int FI) const |
| getFrameIndexReferenceFromSP - This method returns the offset from the stack pointer to the slot of the specified index. | |
| virtual void | getCalleeSaves (const MachineFunction &MF, BitVector &SavedRegs) const |
Returns the callee-saved registers as computed by determineCalleeSaves in the BitVector SavedRegs. | |
| virtual void | determineCalleeSaves (MachineFunction &MF, BitVector &SavedRegs, RegScavenger *RS=nullptr) const |
| This method determines which of the registers reported by TargetRegisterInfo::getCalleeSavedRegs() should actually get saved. | |
| virtual void | processFunctionBeforeFrameFinalized (MachineFunction &MF, RegScavenger *RS=nullptr) const |
| processFunctionBeforeFrameFinalized - This method is called immediately before the specified function's frame layout (MF.getFrameInfo()) is finalized. | |
| 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. | |
| virtual unsigned | getWinEHParentFrameOffset (const MachineFunction &MF) const |
| virtual MachineBasicBlock::iterator | eliminateCallFramePseudoInstr (MachineFunction &MF, MachineBasicBlock &MBB, MachineBasicBlock::iterator MI) const |
| 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). | |
| virtual void | orderFrameObjects (const MachineFunction &MF, SmallVectorImpl< int > &objectsToAllocate) const |
| Order the symbols in the local stack frame. | |
| virtual bool | canUseAsPrologue (const MachineBasicBlock &MBB) const |
Check whether or not the given MBB can be used as a prologue for the target. | |
| virtual bool | canUseAsEpilogue (const MachineBasicBlock &MBB) const |
Check whether or not the given MBB can be used as a epilogue for the target. | |
| virtual TargetStackID::Value | getStackIDForScalableVectors () const |
| Returns the StackID that scalable vectors should be associated with. | |
| 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. | |
| virtual int | getInitialCFAOffset (const MachineFunction &MF) const |
| Return initial CFA offset value i.e. | |
| virtual Register | getInitialCFARegister (const MachineFunction &MF) const |
| Return initial CFA register value i.e. | |
| virtual DwarfFrameBase | getDwarfFrameBase (const MachineFunction &MF) const |
| Return the frame base information to be encoded in the DWARF subprogram debug info. | |
| virtual void | spillFPBP (MachineFunction &MF) const |
| If frame pointer or base pointer is clobbered by an instruction, we should spill/restore it around that instruction. | |
| virtual void | emitRemarks (const MachineFunction &MF, MachineOptimizationRemarkEmitter *ORE) const |
| This method is called at the end of prolog/epilog code insertion, so targets can emit remarks based on the final frame layout. | |
Additional Inherited Members | |
| Public Types inherited from llvm::TargetFrameLowering | |
| enum | StackDirection { StackGrowsUp , StackGrowsDown } |
| 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. | |
Detailed Description
Definition at line 20 of file XtensaFrameLowering.h.
Constructor & Destructor Documentation
◆ XtensaFrameLowering()
| XtensaFrameLowering::XtensaFrameLowering | ( | const XtensaSubtarget & | STI | ) |
Definition at line 25 of file XtensaFrameLowering.cpp.
Member Function Documentation
◆ determineCalleeSaves()
|
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 246 of file XtensaFrameLowering.cpp.
References llvm::TargetFrameLowering::determineCalleeSaves(), FP, llvm::XtensaRegisterInfo::getFrameRegister(), hasFP(), and llvm::BitVector::set().
◆ eliminateCallFramePseudoInstr()
|
overridevirtual |
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).
It is responsible for eliminating these instructions, replacing them with concrete instructions. This method need only be implemented if using call frame setup/destroy pseudo instructions. Returns an iterator pointing to the instruction after the replaced one.
Reimplemented from llvm::TargetFrameLowering.
Definition at line 228 of file XtensaFrameLowering.cpp.
References llvm::MachineBasicBlock::erase(), llvm::TargetSubtargetInfo::getInstrInfo(), llvm::MachineFunction::getSubtarget(), llvm::TargetFrameLowering::hasReservedCallFrame(), I, MBB, and TII.
◆ emitEpilogue()
|
overridevirtual |
Implements llvm::TargetFrameLowering.
Definition at line 138 of file XtensaFrameLowering.cpp.
References llvm::MachineInstrBuilder::addReg(), llvm::XtensaInstrInfo::adjustStackPtr(), assert(), llvm::BuildMI(), DL, FP, llvm::MachineFrameInfo::getCalleeSavedInfo(), llvm::MachineFunction::getFrameInfo(), llvm::XtensaRegisterInfo::getFrameRegister(), llvm::MachineBasicBlock::getLastNonDebugInstr(), llvm::MachineFrameInfo::getStackSize(), hasFP(), I, Info, llvm::XtensaInstrInfo::isLoadFromStackSlot(), MBB, and MBBI.
◆ emitPrologue()
|
overridevirtual |
emitProlog/emitEpilog - These methods insert prolog and epilog code into the function.
Implements llvm::TargetFrameLowering.
Definition at line 36 of file XtensaFrameLowering.cpp.
References llvm::MachineInstrBuilder::addCFIIndex(), llvm::MachineFunction::addFrameInst(), llvm::MachineInstrBuilder::addReg(), llvm::MachineFrameInfo::adjustsStack(), llvm::XtensaInstrInfo::adjustStackPtr(), assert(), llvm::MachineBasicBlock::begin(), llvm::BuildMI(), llvm::MCCFIInstruction::cfiDefCfaOffset(), llvm::MCCFIInstruction::createDefCfaRegister(), llvm::MCCFIInstruction::createOffset(), DL, llvm::MachineBasicBlock::end(), FP, llvm::MachineInstr::FrameSetup, llvm::MachineFunction::front(), llvm::MachineFrameInfo::getCalleeSavedInfo(), llvm::MachineFunction::getContext(), llvm::MachineFunction::getFrameInfo(), llvm::XtensaRegisterInfo::getFrameRegister(), llvm::MachineFrameInfo::getObjectIndexBegin(), llvm::MachineFrameInfo::getObjectIndexEnd(), llvm::MachineFrameInfo::getObjectOffset(), llvm::MCContext::getRegisterInfo(), llvm::MachineFrameInfo::getStackSize(), hasFP(), I, Info, llvm::MachineFrameInfo::isDeadObjectIndex(), llvm::XtensaInstrInfo::isStoreToStackSlot(), MBB, MBBI, MRI, llvm::Offset, llvm::MachineInstrBuilder::setMIFlag(), llvm::MachineFrameInfo::setObjectOffset(), and llvm::MachineFrameInfo::setStackSize().
◆ hasFP()
|
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 30 of file XtensaFrameLowering.cpp.
References llvm::TargetOptions::DisableFramePointerElim(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getTarget(), llvm::MachineFrameInfo::hasVarSizedObjects(), and llvm::TargetMachine::Options.
Referenced by determineCalleeSaves(), emitEpilogue(), and emitPrologue().
◆ processFunctionBeforeFrameFinalized()
|
overridevirtual |
processFunctionBeforeFrameFinalized - This method is called immediately before the specified function's frame layout (MF.getFrameInfo()) is finalized.
Once the frame is finalized, MO_FrameIndex operands are replaced with direct constants. This method is optional.
Reimplemented from llvm::TargetFrameLowering.
Definition at line 258 of file XtensaFrameLowering.cpp.
References llvm::RegScavenger::addScavengingFrameIndex(), llvm::MachineFrameInfo::CreateStackObject(), llvm::MachineFrameInfo::estimateStackSize(), llvm::MachineFunction::getFrameInfo(), and Size.
◆ restoreCalleeSavedRegisters()
|
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 221 of file XtensaFrameLowering.cpp.
References MBB, MI, llvm::TargetFrameLowering::restoreCalleeSavedRegisters(), and TRI.
◆ spillCalleeSavedRegisters()
|
overridevirtual |
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().
Returns false otherwise.
Reimplemented from llvm::TargetFrameLowering.
Definition at line 193 of file XtensaFrameLowering.cpp.
References llvm::MachineBasicBlock::addLiveIn(), llvm::MachineFunction::begin(), llvm::MachineFunction::getFrameInfo(), llvm::MachineBasicBlock::getParent(), llvm::MachineFrameInfo::isReturnAddressTaken(), MBB, MI, llvm::ArrayRef< T >::size(), llvm::XtensaInstrInfo::storeRegToStackSlot(), and TRI.
The documentation for this class was generated from the following files:
- lib/Target/Xtensa/XtensaFrameLowering.h
- lib/Target/Xtensa/XtensaFrameLowering.cpp
