ARMMachineFunctionInfo.h

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//===-- ARMMachineFuctionInfo.h - ARM machine function info -----*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file declares ARM-specific per-machine-function information.
//
//===----------------------------------------------------------------------===//

#ifndef ARMMACHINEFUNCTIONINFO_H
#define ARMMACHINEFUNCTIONINFO_H

#include "ARMSubtarget.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetRegisterInfo.h"

namespace llvm {

/// ARMFunctionInfo - This class is derived from MachineFunctionInfo and
/// contains private ARM-specific information for each MachineFunction.
class ARMFunctionInfo : public MachineFunctionInfo {
  virtual void anchor();

  /// isThumb - True if this function is compiled under Thumb mode.
  /// Used to initialized Align, so must precede it.
  bool isThumb;

  /// hasThumb2 - True if the target architecture supports Thumb2. Do not use
  /// to determine if function is compiled under Thumb mode, for that use
  /// 'isThumb'.
  bool hasThumb2;

  /// StByValParamsPadding - For parameter that is split between
  /// GPRs and memory; while recovering GPRs part, when
  /// StackAlignment == 8, and GPRs-part-size mod 8 != 0,
  /// we need to insert gap before parameter start address. It allows to
  /// "attach" GPR-part to the part that was passed via stack.
  unsigned StByValParamsPadding;

  /// VarArgsRegSaveSize - Size of the register save area for vararg functions.
  ///
  unsigned ArgRegsSaveSize;

  /// HasStackFrame - True if this function has a stack frame. Set by
  /// processFunctionBeforeCalleeSavedScan().
  bool HasStackFrame;

  /// RestoreSPFromFP - True if epilogue should restore SP from FP. Set by
  /// emitPrologue.
  bool RestoreSPFromFP;

  /// LRSpilledForFarJump - True if the LR register has been for spilled to
  /// enable far jump.
  bool LRSpilledForFarJump;

  /// FramePtrSpillOffset - If HasStackFrame, this records the frame pointer
  /// spill stack offset.
  unsigned FramePtrSpillOffset;

  /// GPRCS1Offset, GPRCS2Offset, DPRCSOffset - Starting offset of callee saved
  /// register spills areas. For Mac OS X:
  ///
  /// GPR callee-saved (1) : r4, r5, r6, r7, lr
  /// --------------------------------------------
  /// GPR callee-saved (2) : r8, r10, r11
  /// --------------------------------------------
  /// DPR callee-saved : d8 - d15
  ///
  /// Also see AlignedDPRCSRegs below. Not all D-regs need to go in area 3.
  /// Some may be spilled after the stack has been realigned.
  unsigned GPRCS1Offset;
  unsigned GPRCS2Offset;
  unsigned DPRCSOffset;

  /// GPRCS1Size, GPRCS2Size, DPRCSSize - Sizes of callee saved register spills
  /// areas.
  unsigned GPRCS1Size;
  unsigned GPRCS2Size;
  unsigned DPRCSSize;

  /// NumAlignedDPRCS2Regs - The number of callee-saved DPRs that are saved in
  /// the aligned portion of the stack frame.  This is always a contiguous
  /// sequence of D-registers starting from d8.
  ///
  /// We do not keep track of the frame indices used for these registers - they
  /// behave like any other frame index in the aligned stack frame.  These
  /// registers also aren't included in DPRCSSize above.
  unsigned NumAlignedDPRCS2Regs;

  /// JumpTableUId - Unique id for jumptables.
  ///
  unsigned JumpTableUId;

  unsigned PICLabelUId;

  /// VarArgsFrameIndex - FrameIndex for start of varargs area.
  int VarArgsFrameIndex;

  /// HasITBlocks - True if IT blocks have been inserted.
  bool HasITBlocks;

  /// CPEClones - Track constant pool entries clones created by Constant Island
  /// pass.
  DenseMap<unsigned, unsigned> CPEClones;

  /// GlobalBaseReg - keeps track of the virtual register initialized for
  /// use as the global base register. This is used for PIC in some PIC
  /// relocation models.
  unsigned GlobalBaseReg;

public:
  ARMFunctionInfo() :
    isThumb(false),
    hasThumb2(false),
    ArgRegsSaveSize(0), HasStackFrame(false), RestoreSPFromFP(false),
    LRSpilledForFarJump(false),
    FramePtrSpillOffset(0), GPRCS1Offset(0), GPRCS2Offset(0), DPRCSOffset(0),
    GPRCS1Size(0), GPRCS2Size(0), DPRCSSize(0),
    NumAlignedDPRCS2Regs(0),
    JumpTableUId(0), PICLabelUId(0),
    VarArgsFrameIndex(0), HasITBlocks(false), GlobalBaseReg(0) {}

  explicit ARMFunctionInfo(MachineFunction &MF) :
    isThumb(MF.getTarget().getSubtarget<ARMSubtarget>().isThumb()),
    hasThumb2(MF.getTarget().getSubtarget<ARMSubtarget>().hasThumb2()),
    StByValParamsPadding(0),
    ArgRegsSaveSize(0), HasStackFrame(false), RestoreSPFromFP(false),
    LRSpilledForFarJump(false),
    FramePtrSpillOffset(0), GPRCS1Offset(0), GPRCS2Offset(0), DPRCSOffset(0),
    GPRCS1Size(0), GPRCS2Size(0), DPRCSSize(0),
    JumpTableUId(0), PICLabelUId(0),
    VarArgsFrameIndex(0), HasITBlocks(false), GlobalBaseReg(0) {}

  bool isThumbFunction() const { return isThumb; }
  bool isThumb1OnlyFunction() const { return isThumb && !hasThumb2; }
  bool isThumb2Function() const { return isThumb && hasThumb2; }

  unsigned getStoredByValParamsPadding() const { return StByValParamsPadding; }
  void setStoredByValParamsPadding(unsigned p) { StByValParamsPadding = p; }

  unsigned getArgRegsSaveSize(unsigned Align = 0) const {
    if (!Align)
      return ArgRegsSaveSize;
    return (ArgRegsSaveSize + Align - 1) & ~(Align - 1);
  }
  void setArgRegsSaveSize(unsigned s) { ArgRegsSaveSize = s; }

  bool hasStackFrame() const { return HasStackFrame; }
  void setHasStackFrame(bool s) { HasStackFrame = s; }

  bool shouldRestoreSPFromFP() const { return RestoreSPFromFP; }
  void setShouldRestoreSPFromFP(bool s) { RestoreSPFromFP = s; }

  bool isLRSpilledForFarJump() const { return LRSpilledForFarJump; }
  void setLRIsSpilledForFarJump(bool s) { LRSpilledForFarJump = s; }

  unsigned getFramePtrSpillOffset() const { return FramePtrSpillOffset; }
  void setFramePtrSpillOffset(unsigned o) { FramePtrSpillOffset = o; }

  unsigned getNumAlignedDPRCS2Regs() const { return NumAlignedDPRCS2Regs; }
  void setNumAlignedDPRCS2Regs(unsigned n) { NumAlignedDPRCS2Regs = n; }

  unsigned getGPRCalleeSavedArea1Offset() const { return GPRCS1Offset; }
  unsigned getGPRCalleeSavedArea2Offset() const { return GPRCS2Offset; }
  unsigned getDPRCalleeSavedAreaOffset()  const { return DPRCSOffset; }

  void setGPRCalleeSavedArea1Offset(unsigned o) { GPRCS1Offset = o; }
  void setGPRCalleeSavedArea2Offset(unsigned o) { GPRCS2Offset = o; }
  void setDPRCalleeSavedAreaOffset(unsigned o)  { DPRCSOffset = o; }

  unsigned getGPRCalleeSavedArea1Size() const { return GPRCS1Size; }
  unsigned getGPRCalleeSavedArea2Size() const { return GPRCS2Size; }
  unsigned getDPRCalleeSavedAreaSize()  const { return DPRCSSize; }

  void setGPRCalleeSavedArea1Size(unsigned s) { GPRCS1Size = s; }
  void setGPRCalleeSavedArea2Size(unsigned s) { GPRCS2Size = s; }
  void setDPRCalleeSavedAreaSize(unsigned s)  { DPRCSSize = s; }

  unsigned createJumpTableUId() {
    return JumpTableUId++;
  }

  unsigned getNumJumpTables() const {
    return JumpTableUId;
  }

  void initPICLabelUId(unsigned UId) {
    PICLabelUId = UId;
  }

  unsigned getNumPICLabels() const {
    return PICLabelUId;
  }

  unsigned createPICLabelUId() {
    return PICLabelUId++;
  }

  int getVarArgsFrameIndex() const { return VarArgsFrameIndex; }
  void setVarArgsFrameIndex(int Index) { VarArgsFrameIndex = Index; }

  bool hasITBlocks() const { return HasITBlocks; }
  void setHasITBlocks(bool h) { HasITBlocks = h; }

  unsigned getGlobalBaseReg() const { return GlobalBaseReg; }
  void setGlobalBaseReg(unsigned Reg) { GlobalBaseReg = Reg; }

  void recordCPEClone(unsigned CPIdx, unsigned CPCloneIdx) {
    if (!CPEClones.insert(std::make_pair(CPCloneIdx, CPIdx)).second)
      assert(0 && "Duplicate entries!");
  }

  unsigned getOriginalCPIdx(unsigned CloneIdx) const {
    DenseMap<unsigned, unsigned>::const_iterator I = CPEClones.find(CloneIdx);
    if (I != CPEClones.end())
      return I->second;
    else
      return -1U;
  }
};
} // End llvm namespace

#endif // ARMMACHINEFUNCTIONINFO_H