223 lines
		
	
	
		
			9.8 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			223 lines
		
	
	
		
			9.8 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===-- X86TargetFrameLowering.h - Define frame lowering for X86 -*- C++ -*-==//
 | |
| //
 | |
| //                     The LLVM Compiler Infrastructure
 | |
| //
 | |
| // This file is distributed under the University of Illinois Open Source
 | |
| // License. See LICENSE.TXT for details.
 | |
| //
 | |
| //===----------------------------------------------------------------------===//
 | |
| //
 | |
| // This class implements X86-specific bits of TargetFrameLowering class.
 | |
| //
 | |
| //===----------------------------------------------------------------------===//
 | |
| 
 | |
| #ifndef LLVM_LIB_TARGET_X86_X86FRAMELOWERING_H
 | |
| #define LLVM_LIB_TARGET_X86_X86FRAMELOWERING_H
 | |
| 
 | |
| #include "llvm/Target/TargetFrameLowering.h"
 | |
| 
 | |
| namespace llvm {
 | |
| 
 | |
| class MachineInstrBuilder;
 | |
| class MCCFIInstruction;
 | |
| class X86Subtarget;
 | |
| class X86RegisterInfo;
 | |
| 
 | |
| class X86FrameLowering : public TargetFrameLowering {
 | |
| public:
 | |
|   X86FrameLowering(const X86Subtarget &STI, unsigned StackAlignOverride);
 | |
| 
 | |
|   // Cached subtarget predicates.
 | |
| 
 | |
|   const X86Subtarget &STI;
 | |
|   const TargetInstrInfo &TII;
 | |
|   const X86RegisterInfo *TRI;
 | |
| 
 | |
|   unsigned SlotSize;
 | |
| 
 | |
|   /// Is64Bit implies that x86_64 instructions are available.
 | |
|   bool Is64Bit;
 | |
| 
 | |
|   bool IsLP64;
 | |
| 
 | |
|   /// True if the 64-bit frame or stack pointer should be used. True for most
 | |
|   /// 64-bit targets with the exception of x32. If this is false, 32-bit
 | |
|   /// instruction operands should be used to manipulate StackPtr and FramePtr.
 | |
|   bool Uses64BitFramePtr;
 | |
| 
 | |
|   unsigned StackPtr;
 | |
| 
 | |
|   /// Emit target stack probe code. This is required for all
 | |
|   /// large stack allocations on Windows. The caller is required to materialize
 | |
|   /// the number of bytes to probe in RAX/EAX. Returns instruction just
 | |
|   /// after the expansion.
 | |
|   MachineInstr *emitStackProbe(MachineFunction &MF, MachineBasicBlock &MBB,
 | |
|                                MachineBasicBlock::iterator MBBI,
 | |
|                                const DebugLoc &DL, bool InProlog) const;
 | |
| 
 | |
|   /// Replace a StackProbe inline-stub with the actual probe code inline.
 | |
|   void inlineStackProbe(MachineFunction &MF,
 | |
|                         MachineBasicBlock &PrologMBB) const override;
 | |
| 
 | |
|   void emitCalleeSavedFrameMoves(MachineBasicBlock &MBB,
 | |
|                                  MachineBasicBlock::iterator MBBI,
 | |
|                                  const DebugLoc &DL) const;
 | |
| 
 | |
|   /// emitProlog/emitEpilog - These methods insert prolog and epilog code into
 | |
|   /// the function.
 | |
|   void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
 | |
|   void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
 | |
| 
 | |
|   void adjustForSegmentedStacks(MachineFunction &MF,
 | |
|                                 MachineBasicBlock &PrologueMBB) const override;
 | |
| 
 | |
|   void adjustForHiPEPrologue(MachineFunction &MF,
 | |
|                              MachineBasicBlock &PrologueMBB) const override;
 | |
| 
 | |
|   void determineCalleeSaves(MachineFunction &MF, BitVector &SavedRegs,
 | |
|                             RegScavenger *RS = nullptr) const override;
 | |
| 
 | |
|   bool
 | |
|   assignCalleeSavedSpillSlots(MachineFunction &MF,
 | |
|                               const TargetRegisterInfo *TRI,
 | |
|                               std::vector<CalleeSavedInfo> &CSI) const override;
 | |
| 
 | |
|   bool spillCalleeSavedRegisters(MachineBasicBlock &MBB,
 | |
|                                  MachineBasicBlock::iterator MI,
 | |
|                                  const std::vector<CalleeSavedInfo> &CSI,
 | |
|                                  const TargetRegisterInfo *TRI) const override;
 | |
| 
 | |
|   bool restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
 | |
|                                   MachineBasicBlock::iterator MI,
 | |
|                                   const std::vector<CalleeSavedInfo> &CSI,
 | |
|                                   const TargetRegisterInfo *TRI) const override;
 | |
| 
 | |
|   bool hasFP(const MachineFunction &MF) const override;
 | |
|   bool hasReservedCallFrame(const MachineFunction &MF) const override;
 | |
|   bool canSimplifyCallFramePseudos(const MachineFunction &MF) const override;
 | |
|   bool needsFrameIndexResolution(const MachineFunction &MF) const override;
 | |
| 
 | |
|   int getFrameIndexReference(const MachineFunction &MF, int FI,
 | |
|                              unsigned &FrameReg) const override;
 | |
| 
 | |
|   int getFrameIndexReferencePreferSP(const MachineFunction &MF, int FI,
 | |
|                                      unsigned &FrameReg,
 | |
|                                      bool IgnoreSPUpdates) const override;
 | |
| 
 | |
|   MachineBasicBlock::iterator
 | |
|   eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
 | |
|                                 MachineBasicBlock::iterator MI) const override;
 | |
| 
 | |
|   unsigned getWinEHParentFrameOffset(const MachineFunction &MF) const override;
 | |
| 
 | |
|   void processFunctionBeforeFrameFinalized(MachineFunction &MF,
 | |
|                                            RegScavenger *RS) const override;
 | |
| 
 | |
|   /// Check the instruction before/after the passed instruction. If
 | |
|   /// it is an ADD/SUB/LEA instruction it is deleted argument and the
 | |
|   /// stack adjustment is returned as a positive value for ADD/LEA and
 | |
|   /// a negative for SUB.
 | |
|   int mergeSPUpdates(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI,
 | |
|                      bool doMergeWithPrevious) const;
 | |
| 
 | |
|   /// Emit a series of instructions to increment / decrement the stack
 | |
|   /// pointer by a constant value.
 | |
|   void emitSPUpdate(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI,
 | |
|                     int64_t NumBytes, bool InEpilogue) const;
 | |
| 
 | |
|   /// Check that LEA can be used on SP in an epilogue sequence for \p MF.
 | |
|   bool canUseLEAForSPInEpilogue(const MachineFunction &MF) const;
 | |
| 
 | |
|   /// Check whether or not the given \p MBB can be used as a prologue
 | |
|   /// for the target.
 | |
|   /// The prologue will be inserted first in this basic block.
 | |
|   /// This method is used by the shrink-wrapping pass to decide if
 | |
|   /// \p MBB will be correctly handled by the target.
 | |
|   /// As soon as the target enable shrink-wrapping without overriding
 | |
|   /// this method, we assume that each basic block is a valid
 | |
|   /// prologue.
 | |
|   bool canUseAsPrologue(const MachineBasicBlock &MBB) const override;
 | |
| 
 | |
|   /// Check whether or not the given \p MBB can be used as a epilogue
 | |
|   /// for the target.
 | |
|   /// The epilogue will be inserted before the first terminator of that block.
 | |
|   /// This method is used by the shrink-wrapping pass to decide if
 | |
|   /// \p MBB will be correctly handled by the target.
 | |
|   bool canUseAsEpilogue(const MachineBasicBlock &MBB) const override;
 | |
| 
 | |
|   /// Returns true if the target will correctly handle shrink wrapping.
 | |
|   bool enableShrinkWrapping(const MachineFunction &MF) const override;
 | |
| 
 | |
|   /// Order the symbols in the local stack.
 | |
|   /// We want to place the local stack objects in some sort of sensible order.
 | |
|   /// The heuristic we use is to try and pack them according to static number
 | |
|   /// of uses and size in order to minimize code size.
 | |
|   void orderFrameObjects(const MachineFunction &MF,
 | |
|                          SmallVectorImpl<int> &ObjectsToAllocate) const override;
 | |
| 
 | |
|   /// convertArgMovsToPushes - This method tries to convert a call sequence
 | |
|   /// that uses sub and mov instructions to put the argument onto the stack
 | |
|   /// into a series of pushes.
 | |
|   /// Returns true if the transformation succeeded, false if not.
 | |
|   bool convertArgMovsToPushes(MachineFunction &MF, 
 | |
|                               MachineBasicBlock &MBB,
 | |
|                               MachineBasicBlock::iterator I, 
 | |
|                               uint64_t Amount) const;
 | |
| 
 | |
|   /// Wraps up getting a CFI index and building a MachineInstr for it.
 | |
|   void BuildCFI(MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI,
 | |
|                 const DebugLoc &DL, const MCCFIInstruction &CFIInst) const;
 | |
| 
 | |
|   /// Sets up EBP and optionally ESI based on the incoming EBP value.  Only
 | |
|   /// needed for 32-bit. Used in funclet prologues and at catchret destinations.
 | |
|   MachineBasicBlock::iterator
 | |
|   restoreWin32EHStackPointers(MachineBasicBlock &MBB,
 | |
|                               MachineBasicBlock::iterator MBBI,
 | |
|                               const DebugLoc &DL, bool RestoreSP = false) const;
 | |
| 
 | |
| private:
 | |
|   uint64_t calculateMaxStackAlign(const MachineFunction &MF) const;
 | |
| 
 | |
|   /// Emit target stack probe as a call to a helper function
 | |
|   MachineInstr *emitStackProbeCall(MachineFunction &MF, MachineBasicBlock &MBB,
 | |
|                                    MachineBasicBlock::iterator MBBI,
 | |
|                                    const DebugLoc &DL, bool InProlog) const;
 | |
| 
 | |
|   /// Emit target stack probe as an inline sequence.
 | |
|   MachineInstr *emitStackProbeInline(MachineFunction &MF,
 | |
|                                      MachineBasicBlock &MBB,
 | |
|                                      MachineBasicBlock::iterator MBBI,
 | |
|                                      const DebugLoc &DL, bool InProlog) const;
 | |
| 
 | |
|   /// Emit a stub to later inline the target stack probe.
 | |
|   MachineInstr *emitStackProbeInlineStub(MachineFunction &MF,
 | |
|                                          MachineBasicBlock &MBB,
 | |
|                                          MachineBasicBlock::iterator MBBI,
 | |
|                                          const DebugLoc &DL,
 | |
|                                          bool InProlog) const;
 | |
| 
 | |
|   /// Aligns the stack pointer by ANDing it with -MaxAlign.
 | |
|   void BuildStackAlignAND(MachineBasicBlock &MBB,
 | |
|                           MachineBasicBlock::iterator MBBI, const DebugLoc &DL,
 | |
|                           unsigned Reg, uint64_t MaxAlign) const;
 | |
| 
 | |
|   /// Make small positive stack adjustments using POPs.
 | |
|   bool adjustStackWithPops(MachineBasicBlock &MBB,
 | |
|                            MachineBasicBlock::iterator MBBI, const DebugLoc &DL,
 | |
|                            int Offset) const;
 | |
| 
 | |
|   /// Adjusts the stack pointer using LEA, SUB, or ADD.
 | |
|   MachineInstrBuilder BuildStackAdjustment(MachineBasicBlock &MBB,
 | |
|                                            MachineBasicBlock::iterator MBBI,
 | |
|                                            const DebugLoc &DL, int64_t Offset,
 | |
|                                            bool InEpilogue) const;
 | |
| 
 | |
|   unsigned getPSPSlotOffsetFromSP(const MachineFunction &MF) const;
 | |
| 
 | |
|   unsigned getWinEHFuncletFrameSize(const MachineFunction &MF) const;
 | |
| };
 | |
| 
 | |
| } // End llvm namespace
 | |
| 
 | |
| #endif
 |