LLVM  6.0.0svn
Public Member Functions | List of all members
llvm::BPFFrameLowering Class Reference

#include "Target/BPF/BPFFrameLowering.h"

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

 BPFFrameLowering (const BPFSubtarget &sti)
 
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
 
bool hasFP (const MachineFunction &MF) const override
 hasFP - Return true if the specified function should have a dedicated frame pointer register. More...
 
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...
 
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, unsigned StackAl, int LAO, unsigned TransAl=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...
 
int alignSPAdjust (int SPAdj) const
 alignSPAdjust - This method aligns the stack adjustment to the correct alignment. More...
 
unsigned getTransientStackAlignment () 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...
 
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 isFPCloseToIncomingSP () const
 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...
 
virtual bool assignCalleeSavedSpillSlots (MachineFunction &MF, const TargetRegisterInfo *TRI, std::vector< CalleeSavedInfo > &CSI) 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 void inlineStackProbe (MachineFunction &MF, MachineBasicBlock &PrologueMBB) const
 Replace a StackProbe stub (if any) with the actual probe code inline. 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 spillCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, const std::vector< 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(). More...
 
virtual bool restoreCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, std::vector< 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(). More...
 
virtual bool noFramePointerElim (const MachineFunction &MF) const
 Return true if the target needs to disable frame pointer elimination. More...
 
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. 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 int getFrameIndexReference (const MachineFunction &MF, int FI, unsigned &FrameReg) const
 getFrameIndexReference - This method should return the base register and offset used to reference a frame index location. More...
 
virtual int getFrameIndexReferencePreferSP (const MachineFunction &MF, int FI, unsigned &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 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. 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...
 

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. More...
 

Detailed Description

Definition at line 22 of file BPFFrameLowering.h.

Constructor & Destructor Documentation

◆ BPFFrameLowering()

llvm::BPFFrameLowering::BPFFrameLowering ( const BPFSubtarget sti)
inlineexplicit

Definition at line 24 of file BPFFrameLowering.h.

References determineCalleeSaves(), emitEpilogue(), emitPrologue(), and hasFP().

Member Function Documentation

◆ determineCalleeSaves()

void BPFFrameLowering::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.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 32 of file BPFFrameLowering.cpp.

References llvm::TargetFrameLowering::determineCalleeSaves(), R6, and llvm::BitVector::reset().

Referenced by BPFFrameLowering().

◆ eliminateCallFramePseudoInstr()

MachineBasicBlock::iterator llvm::BPFFrameLowering::eliminateCallFramePseudoInstr ( MachineFunction MF,
MachineBasicBlock MBB,
MachineBasicBlock::iterator  MI 
) const
inlineoverridevirtual

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 35 of file BPFFrameLowering.h.

References llvm::MachineBasicBlock::erase().

◆ emitEpilogue()

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

Implements llvm::TargetFrameLowering.

Definition at line 29 of file BPFFrameLowering.cpp.

Referenced by BPFFrameLowering().

◆ emitPrologue()

void BPFFrameLowering::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 26 of file BPFFrameLowering.cpp.

Referenced by BPFFrameLowering().

◆ hasFP()

bool BPFFrameLowering::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 24 of file BPFFrameLowering.cpp.

Referenced by BPFFrameLowering().


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