MipsInstrInfo.h revision 01a76ce8d910c0ffee89beaa3819d3448791950f 
1//===- MipsInstrInfo.h - Mips Instruction Information -----------*- 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 Mips implementation of the TargetInstrInfo class.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef MIPSINSTRUCTIONINFO_H
15#define MIPSINSTRUCTIONINFO_H
16
17#include "Mips.h"
18#include "llvm/Support/ErrorHandling.h"
19#include "llvm/Target/TargetInstrInfo.h"
20#include "MipsRegisterInfo.h"
21
22namespace llvm {
23
24namespace Mips {
25
26  // Mips Branch Codes
27  enum FPBranchCode {
28    BRANCH_F,
29    BRANCH_T,
30    BRANCH_FL,
31    BRANCH_TL,
32    BRANCH_INVALID
33  };
34
35  // Mips Condition Codes
36  enum CondCode {
37    // To be used with float branch True
38    FCOND_F,
39    FCOND_UN,
40    FCOND_EQ,
41    FCOND_UEQ,
42    FCOND_OLT,
43    FCOND_ULT,
44    FCOND_OLE,
45    FCOND_ULE,
46    FCOND_SF,
47    FCOND_NGLE,
48    FCOND_SEQ,
49    FCOND_NGL,
50    FCOND_LT,
51    FCOND_NGE,
52    FCOND_LE,
53    FCOND_NGT,
54
55    // To be used with float branch False
56    // This conditions have the same mnemonic as the
57    // above ones, but are used with a branch False;
58    FCOND_T,
59    FCOND_OR,
60    FCOND_NEQ,
61    FCOND_OGL,
62    FCOND_UGE,
63    FCOND_OGE,
64    FCOND_UGT,
65    FCOND_OGT,
66    FCOND_ST,
67    FCOND_GLE,
68    FCOND_SNE,
69    FCOND_GL,
70    FCOND_NLT,
71    FCOND_GE,
72    FCOND_NLE,
73    FCOND_GT,
74
75    // Only integer conditions
76    COND_E,
77    COND_GZ,
78    COND_GEZ,
79    COND_LZ,
80    COND_LEZ,
81    COND_NE,
82    COND_INVALID
83  };
84
85  // Turn condition code into conditional branch opcode.
86  unsigned GetCondBranchFromCond(CondCode CC);
87
88  /// GetOppositeBranchCondition - Return the inverse of the specified cond,
89  /// e.g. turning COND_E to COND_NE.
90  CondCode GetOppositeBranchCondition(Mips::CondCode CC);
91
92  /// MipsCCToString - Map each FP condition code to its string
93  inline static const char *MipsFCCToString(Mips::CondCode CC)
94  {
95    switch (CC) {
96      default: llvm_unreachable("Unknown condition code");
97      case FCOND_F:
98      case FCOND_T:   return "f";
99      case FCOND_UN:
100      case FCOND_OR:  return "un";
101      case FCOND_EQ:
102      case FCOND_NEQ: return "eq";
103      case FCOND_UEQ:
104      case FCOND_OGL: return "ueq";
105      case FCOND_OLT:
106      case FCOND_UGE: return "olt";
107      case FCOND_ULT:
108      case FCOND_OGE: return "ult";
109      case FCOND_OLE:
110      case FCOND_UGT: return "ole";
111      case FCOND_ULE:
112      case FCOND_OGT: return "ule";
113      case FCOND_SF:
114      case FCOND_ST:  return "sf";
115      case FCOND_NGLE:
116      case FCOND_GLE: return "ngle";
117      case FCOND_SEQ:
118      case FCOND_SNE: return "seq";
119      case FCOND_NGL:
120      case FCOND_GL:  return "ngl";
121      case FCOND_LT:
122      case FCOND_NLT: return "lt";
123      case FCOND_NGE:
124      case FCOND_GE:  return "ge";
125      case FCOND_LE:
126      case FCOND_NLE: return "nle";
127      case FCOND_NGT:
128      case FCOND_GT:  return "gt";
129    }
130  }
131}
132
133/// MipsII - This namespace holds all of the target specific flags that
134/// instruction info tracks.
135///
136namespace MipsII {
137  /// Target Operand Flag enum.
138  enum TOF {
139    //===------------------------------------------------------------------===//
140    // Mips Specific MachineOperand flags.
141
142    MO_NO_FLAG,
143
144    /// MO_GOT - Represents the offset into the global offset table at which
145    /// the address the relocation entry symbol resides during execution.
146    MO_GOT,
147
148    /// MO_GOT_CALL - Represents the offset into the global offset table at
149    /// which the address of a call site relocation entry symbol resides
150    /// during execution. This is different from the above since this flag
151    /// can only be present in call instructions.
152    MO_GOT_CALL,
153
154    /// MO_GPREL - Represents the offset from the current gp value to be used
155    /// for the relocatable object file being produced.
156    MO_GPREL,
157
158    /// MO_ABS_HILO - Represents the hi or low part of an absolute symbol
159    /// address.
160    MO_ABS_HILO
161
162  };
163}
164
165class MipsInstrInfo : public TargetInstrInfoImpl {
166  MipsTargetMachine &TM;
167  const MipsRegisterInfo RI;
168public:
169  explicit MipsInstrInfo(MipsTargetMachine &TM);
170
171  /// getRegisterInfo - TargetInstrInfo is a superset of MRegister info.  As
172  /// such, whenever a client has an instance of instruction info, it should
173  /// always be able to get register info as well (through this method).
174  ///
175  virtual const MipsRegisterInfo &getRegisterInfo() const { return RI; }
176
177  /// Return true if the instruction is a register to register move and return
178  /// the source and dest operands and their sub-register indices by reference.
179  virtual bool isMoveInstr(const MachineInstr &MI,
180                           unsigned &SrcReg, unsigned &DstReg,
181                           unsigned &SrcSubIdx, unsigned &DstSubIdx) const;
182
183  /// isLoadFromStackSlot - If the specified machine instruction is a direct
184  /// load from a stack slot, return the virtual or physical register number of
185  /// the destination along with the FrameIndex of the loaded stack slot.  If
186  /// not, return 0.  This predicate must return 0 if the instruction has
187  /// any side effects other than loading from the stack slot.
188  virtual unsigned isLoadFromStackSlot(const MachineInstr *MI,
189                                       int &FrameIndex) const;
190
191  /// isStoreToStackSlot - If the specified machine instruction is a direct
192  /// store to a stack slot, return the virtual or physical register number of
193  /// the source reg along with the FrameIndex of the loaded stack slot.  If
194  /// not, return 0.  This predicate must return 0 if the instruction has
195  /// any side effects other than storing to the stack slot.
196  virtual unsigned isStoreToStackSlot(const MachineInstr *MI,
197                                      int &FrameIndex) const;
198
199  /// Branch Analysis
200  virtual bool AnalyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
201                             MachineBasicBlock *&FBB,
202                             SmallVectorImpl<MachineOperand> &Cond,
203                             bool AllowModify) const;
204  virtual unsigned RemoveBranch(MachineBasicBlock &MBB) const;
205  virtual unsigned InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
206                                MachineBasicBlock *FBB,
207                            const SmallVectorImpl<MachineOperand> &Cond) const;
208  virtual bool copyRegToReg(MachineBasicBlock &MBB,
209                            MachineBasicBlock::iterator I,
210                            unsigned DestReg, unsigned SrcReg,
211                            const TargetRegisterClass *DestRC,
212                            const TargetRegisterClass *SrcRC) const;
213  virtual void storeRegToStackSlot(MachineBasicBlock &MBB,
214                                   MachineBasicBlock::iterator MBBI,
215                                   unsigned SrcReg, bool isKill, int FrameIndex,
216                                   const TargetRegisterClass *RC) const;
217
218  virtual void loadRegFromStackSlot(MachineBasicBlock &MBB,
219                                    MachineBasicBlock::iterator MBBI,
220                                    unsigned DestReg, int FrameIndex,
221                                    const TargetRegisterClass *RC) const;
222
223  virtual MachineInstr* foldMemoryOperandImpl(MachineFunction &MF,
224                                              MachineInstr* MI,
225                                           const SmallVectorImpl<unsigned> &Ops,
226                                              int FrameIndex) const;
227
228  virtual MachineInstr* foldMemoryOperandImpl(MachineFunction &MF,
229                                              MachineInstr* MI,
230                                           const SmallVectorImpl<unsigned> &Ops,
231                                              MachineInstr* LoadMI) const {
232    return 0;
233  }
234
235  virtual bool BlockHasNoFallThrough(const MachineBasicBlock &MBB) const;
236  virtual
237  bool ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const;
238
239  /// Insert nop instruction when hazard condition is found
240  virtual void insertNoop(MachineBasicBlock &MBB,
241                          MachineBasicBlock::iterator MI) const;
242
243  /// getGlobalBaseReg - Return a virtual register initialized with the
244  /// the global base register value. Output instructions required to
245  /// initialize the register in the function entry block, if necessary.
246  ///
247  unsigned getGlobalBaseReg(MachineFunction *MF) const;
248};
249
250}
251
252#endif
253