X86RegisterInfo.h revision 31d157ae1ac2cd9c787dc3c1d28e64c682803844 
1//===-- X86RegisterInfo.h - X86 Register Information Impl -------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file contains the X86 implementation of the TargetRegisterInfo class.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef X86REGISTERINFO_H
15#define X86REGISTERINFO_H
16
17#include "llvm/Target/TargetRegisterInfo.h"
18
19#define GET_REGINFO_HEADER
20#include "X86GenRegisterInfo.inc"
21
22namespace llvm {
23  class Type;
24  class TargetInstrInfo;
25  class X86TargetMachine;
26
27class X86RegisterInfo : public X86GenRegisterInfo {
28public:
29  X86TargetMachine &TM;
30  const TargetInstrInfo &TII;
31
32private:
33  /// Is64Bit - Is the target 64-bits.
34  ///
35  bool Is64Bit;
36
37  /// IsWin64 - Is the target on of win64 flavours
38  ///
39  bool IsWin64;
40
41  /// SlotSize - Stack slot size in bytes.
42  ///
43  unsigned SlotSize;
44
45  /// StackPtr - X86 physical register used as stack ptr.
46  ///
47  unsigned StackPtr;
48
49  /// FramePtr - X86 physical register used as frame ptr.
50  ///
51  unsigned FramePtr;
52
53public:
54  X86RegisterInfo(X86TargetMachine &tm, const TargetInstrInfo &tii);
55
56  /// getX86RegNum - Returns the native X86 register number for the given LLVM
57  /// register identifier.
58  static unsigned getX86RegNum(unsigned RegNo);
59
60  // FIXME: This should be tablegen'd like getDwarfRegNum is
61  int getSEHRegNum(unsigned i) const;
62
63  /// getCompactUnwindRegNum - This function maps the register to the number for
64  /// compact unwind encoding. Return -1 if the register isn't valid.
65  int getCompactUnwindRegNum(unsigned RegNum, bool isEH) const;
66
67  /// Code Generation virtual methods...
68  ///
69
70  /// getMatchingSuperRegClass - Return a subclass of the specified register
71  /// class A so that each register in it has a sub-register of the
72  /// specified sub-register index which is in the specified register class B.
73  virtual const TargetRegisterClass *
74  getMatchingSuperRegClass(const TargetRegisterClass *A,
75                           const TargetRegisterClass *B, unsigned Idx) const;
76
77  virtual const TargetRegisterClass *
78  getSubClassWithSubReg(const TargetRegisterClass *RC, unsigned Idx) const;
79
80  const TargetRegisterClass*
81  getLargestLegalSuperClass(const TargetRegisterClass *RC) const;
82
83  /// getPointerRegClass - Returns a TargetRegisterClass used for pointer
84  /// values.
85  const TargetRegisterClass *getPointerRegClass(unsigned Kind = 0) const;
86
87  /// getCrossCopyRegClass - Returns a legal register class to copy a register
88  /// in the specified class to or from. Returns NULL if it is possible to copy
89  /// between a two registers of the specified class.
90  const TargetRegisterClass *
91  getCrossCopyRegClass(const TargetRegisterClass *RC) const;
92
93  unsigned getRegPressureLimit(const TargetRegisterClass *RC,
94                               MachineFunction &MF) const;
95
96  /// getCalleeSavedRegs - Return a null-terminated list of all of the
97  /// callee-save registers on this target.
98  const unsigned *getCalleeSavedRegs(const MachineFunction* MF = 0) const;
99  const uint32_t *getCallPreservedMask(CallingConv::ID) const;
100
101  /// getReservedRegs - Returns a bitset indexed by physical register number
102  /// indicating if a register is a special register that has particular uses and
103  /// should be considered unavailable at all times, e.g. SP, RA. This is used by
104  /// register scavenger to determine what registers are free.
105  BitVector getReservedRegs(const MachineFunction &MF) const;
106
107  bool canRealignStack(const MachineFunction &MF) const;
108
109  bool needsStackRealignment(const MachineFunction &MF) const;
110
111  bool hasReservedSpillSlot(const MachineFunction &MF, unsigned Reg,
112                            int &FrameIdx) const;
113
114  void eliminateCallFramePseudoInstr(MachineFunction &MF,
115                                     MachineBasicBlock &MBB,
116                                     MachineBasicBlock::iterator MI) const;
117
118  void eliminateFrameIndex(MachineBasicBlock::iterator MI,
119                           int SPAdj, RegScavenger *RS = NULL) const;
120
121  // Debug information queries.
122  unsigned getFrameRegister(const MachineFunction &MF) const;
123  unsigned getStackRegister() const { return StackPtr; }
124  // FIXME: Move to FrameInfok
125  unsigned getSlotSize() const { return SlotSize; }
126
127  // Exception handling queries.
128  unsigned getEHExceptionRegister() const;
129  unsigned getEHHandlerRegister() const;
130};
131
132// getX86SubSuperRegister - X86 utility function. It returns the sub or super
133// register of a specific X86 register.
134// e.g. getX86SubSuperRegister(X86::EAX, EVT::i16) return X86:AX
135unsigned getX86SubSuperRegister(unsigned, EVT, bool High=false);
136
137} // End llvm namespace
138
139#endif
140