X86RegisterInfo.h revision dff4b4c5a7cc894d3b4b6c6e779ea8f47fa50630 
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#include "X86GenRegisterInfo.h.inc"
19
20namespace llvm {
21  class Type;
22  class TargetInstrInfo;
23  class X86TargetMachine;
24
25/// N86 namespace - Native X86 register numbers
26///
27namespace N86 {
28  enum {
29    EAX = 0, ECX = 1, EDX = 2, EBX = 3, ESP = 4, EBP = 5, ESI = 6, EDI = 7
30  };
31}
32
33namespace X86 {
34  /// SubregIndex - The index of various sized subregister classes. Note that
35  /// these indices must be kept in sync with the class indices in the
36  /// X86RegisterInfo.td file.
37  enum SubregIndex {
38    SUBREG_8BIT = 1, SUBREG_8BIT_HI = 2, SUBREG_16BIT = 3, SUBREG_32BIT = 4,
39    SUBREG_SS = 1, SUBREG_SD = 2, SUBREG_XMM = 3
40  };
41}
42
43/// DWARFFlavour - Flavour of dwarf regnumbers
44///
45namespace DWARFFlavour {
46  enum {
47    X86_64 = 0, X86_32_DarwinEH = 1, X86_32_Generic = 2
48  };
49}
50
51class X86RegisterInfo : public X86GenRegisterInfo {
52public:
53  X86TargetMachine &TM;
54  const TargetInstrInfo &TII;
55
56private:
57  /// Is64Bit - Is the target 64-bits.
58  ///
59  bool Is64Bit;
60
61  /// IsWin64 - Is the target on of win64 flavours
62  ///
63  bool IsWin64;
64
65  /// SlotSize - Stack slot size in bytes.
66  ///
67  unsigned SlotSize;
68
69  /// StackAlign - Default stack alignment.
70  ///
71  unsigned StackAlign;
72
73  /// StackPtr - X86 physical register used as stack ptr.
74  ///
75  unsigned StackPtr;
76
77  /// FramePtr - X86 physical register used as frame ptr.
78  ///
79  unsigned FramePtr;
80
81public:
82  X86RegisterInfo(X86TargetMachine &tm, const TargetInstrInfo &tii);
83
84  /// getX86RegNum - Returns the native X86 register number for the given LLVM
85  /// register identifier.
86  static unsigned getX86RegNum(unsigned RegNo);
87
88  unsigned getStackAlignment() const { return StackAlign; }
89
90  /// getDwarfRegNum - allows modification of X86GenRegisterInfo::getDwarfRegNum
91  /// (created by TableGen) for target dependencies.
92  int getDwarfRegNum(unsigned RegNum, bool isEH) const;
93
94  /// Code Generation virtual methods...
95  ///
96
97  /// getMatchingSuperRegClass - Return a subclass of the specified register
98  /// class A so that each register in it has a sub-register of the
99  /// specified sub-register index which is in the specified register class B.
100  virtual const TargetRegisterClass *
101  getMatchingSuperRegClass(const TargetRegisterClass *A,
102                           const TargetRegisterClass *B, unsigned Idx) const;
103
104  /// getPointerRegClass - Returns a TargetRegisterClass used for pointer
105  /// values.
106  const TargetRegisterClass *getPointerRegClass(unsigned Kind = 0) const;
107
108  /// getCrossCopyRegClass - Returns a legal register class to copy a register
109  /// in the specified class to or from. Returns NULL if it is possible to copy
110  /// between a two registers of the specified class.
111  const TargetRegisterClass *
112  getCrossCopyRegClass(const TargetRegisterClass *RC) const;
113
114  /// getCalleeSavedRegs - Return a null-terminated list of all of the
115  /// callee-save registers on this target.
116  const unsigned *getCalleeSavedRegs(const MachineFunction* MF = 0) const;
117
118  /// getCalleeSavedRegClasses - Return a null-terminated list of the preferred
119  /// register classes to spill each callee-saved register with.  The order and
120  /// length of this list match the getCalleeSavedRegs() list.
121  const TargetRegisterClass* const*
122  getCalleeSavedRegClasses(const MachineFunction *MF = 0) const;
123
124  /// getReservedRegs - Returns a bitset indexed by physical register number
125  /// indicating if a register is a special register that has particular uses and
126  /// should be considered unavailable at all times, e.g. SP, RA. This is used by
127  /// register scavenger to determine what registers are free.
128  BitVector getReservedRegs(const MachineFunction &MF) const;
129
130  bool hasFP(const MachineFunction &MF) const;
131
132  bool canRealignStack(const MachineFunction &MF) const;
133
134  bool needsStackRealignment(const MachineFunction &MF) const;
135
136  bool hasReservedCallFrame(MachineFunction &MF) const;
137
138  bool hasReservedSpillSlot(MachineFunction &MF, unsigned Reg,
139                            int &FrameIdx) const;
140
141  void eliminateCallFramePseudoInstr(MachineFunction &MF,
142                                     MachineBasicBlock &MBB,
143                                     MachineBasicBlock::iterator MI) const;
144
145  unsigned eliminateFrameIndex(MachineBasicBlock::iterator MI,
146                               int SPAdj, FrameIndexValue *Value = NULL,
147                               RegScavenger *RS = NULL) const;
148
149  void processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
150                                            RegScavenger *RS = NULL) const;
151
152  void emitCalleeSavedFrameMoves(MachineFunction &MF, unsigned LabelId,
153                                 unsigned FramePtr) const;
154  void emitPrologue(MachineFunction &MF) const;
155  void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const;
156
157  // Debug information queries.
158  unsigned getRARegister() const;
159  unsigned getFrameRegister(const MachineFunction &MF) const;
160  int getFrameIndexOffset(const MachineFunction &MF, int FI) const;
161  void getInitialFrameState(std::vector<MachineMove> &Moves) const;
162
163  // Exception handling queries.
164  unsigned getEHExceptionRegister() const;
165  unsigned getEHHandlerRegister() const;
166};
167
168// getX86SubSuperRegister - X86 utility function. It returns the sub or super
169// register of a specific X86 register.
170// e.g. getX86SubSuperRegister(X86::EAX, EVT::i16) return X86:AX
171unsigned getX86SubSuperRegister(unsigned, EVT, bool High=false);
172
173} // End llvm namespace
174
175#endif
176