Home | History | Annotate | Download | only in Mips
      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 // FIXME: We need to override TargetInstrInfo::getInlineAsmLength method in
     13 // order for MipsLongBranch pass to work correctly when the code has inline
     14 // assembly.  The returned value doesn't have to be the asm instruction's exact
     15 // size in bytes; MipsLongBranch only expects it to be the correct upper bound.
     16 //===----------------------------------------------------------------------===//
     17 
     18 #ifndef LLVM_LIB_TARGET_MIPS_MIPSINSTRINFO_H
     19 #define LLVM_LIB_TARGET_MIPS_MIPSINSTRINFO_H
     20 
     21 #include "Mips.h"
     22 #include "MipsRegisterInfo.h"
     23 #include "llvm/CodeGen/MachineInstrBuilder.h"
     24 #include "llvm/Support/ErrorHandling.h"
     25 #include "llvm/Target/TargetInstrInfo.h"
     26 
     27 #define GET_INSTRINFO_HEADER
     28 #include "MipsGenInstrInfo.inc"
     29 
     30 namespace llvm {
     31 class MipsSubtarget;
     32 class MipsInstrInfo : public MipsGenInstrInfo {
     33   virtual void anchor();
     34 protected:
     35   const MipsSubtarget &Subtarget;
     36   unsigned UncondBrOpc;
     37 
     38 public:
     39   enum BranchType {
     40     BT_None,       // Couldn't analyze branch.
     41     BT_NoBranch,   // No branches found.
     42     BT_Uncond,     // One unconditional branch.
     43     BT_Cond,       // One conditional branch.
     44     BT_CondUncond, // A conditional branch followed by an unconditional branch.
     45     BT_Indirect    // One indirct branch.
     46   };
     47 
     48   explicit MipsInstrInfo(const MipsSubtarget &STI, unsigned UncondBrOpc);
     49 
     50   static const MipsInstrInfo *create(MipsSubtarget &STI);
     51 
     52   /// Branch Analysis
     53   bool analyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
     54                      MachineBasicBlock *&FBB,
     55                      SmallVectorImpl<MachineOperand> &Cond,
     56                      bool AllowModify) const override;
     57 
     58   unsigned RemoveBranch(MachineBasicBlock &MBB) const override;
     59 
     60   unsigned InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
     61                         MachineBasicBlock *FBB, ArrayRef<MachineOperand> Cond,
     62                         const DebugLoc &DL) const override;
     63 
     64   bool
     65   ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const override;
     66 
     67   BranchType analyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
     68                            MachineBasicBlock *&FBB,
     69                            SmallVectorImpl<MachineOperand> &Cond,
     70                            bool AllowModify,
     71                            SmallVectorImpl<MachineInstr *> &BranchInstrs) const;
     72 
     73   /// Determine the opcode of a non-delay slot form for a branch if one exists.
     74   unsigned getEquivalentCompactForm(const MachineBasicBlock::iterator I) const;
     75 
     76   /// Predicate to determine if an instruction can go in a forbidden slot.
     77   bool SafeInForbiddenSlot(const MachineInstr &MI) const;
     78 
     79   /// Predicate to determine if an instruction has a forbidden slot.
     80   bool HasForbiddenSlot(const MachineInstr &MI) const;
     81 
     82   /// Insert nop instruction when hazard condition is found
     83   void insertNoop(MachineBasicBlock &MBB,
     84                   MachineBasicBlock::iterator MI) const override;
     85 
     86   /// getRegisterInfo - TargetInstrInfo is a superset of MRegister info.  As
     87   /// such, whenever a client has an instance of instruction info, it should
     88   /// always be able to get register info as well (through this method).
     89   ///
     90   virtual const MipsRegisterInfo &getRegisterInfo() const = 0;
     91 
     92   virtual unsigned getOppositeBranchOpc(unsigned Opc) const = 0;
     93 
     94   /// Return the number of bytes of code the specified instruction may be.
     95   unsigned GetInstSizeInBytes(const MachineInstr &MI) const;
     96 
     97   void storeRegToStackSlot(MachineBasicBlock &MBB,
     98                            MachineBasicBlock::iterator MBBI,
     99                            unsigned SrcReg, bool isKill, int FrameIndex,
    100                            const TargetRegisterClass *RC,
    101                            const TargetRegisterInfo *TRI) const override {
    102     storeRegToStack(MBB, MBBI, SrcReg, isKill, FrameIndex, RC, TRI, 0);
    103   }
    104 
    105   void loadRegFromStackSlot(MachineBasicBlock &MBB,
    106                             MachineBasicBlock::iterator MBBI,
    107                             unsigned DestReg, int FrameIndex,
    108                             const TargetRegisterClass *RC,
    109                             const TargetRegisterInfo *TRI) const override {
    110     loadRegFromStack(MBB, MBBI, DestReg, FrameIndex, RC, TRI, 0);
    111   }
    112 
    113   virtual void storeRegToStack(MachineBasicBlock &MBB,
    114                                MachineBasicBlock::iterator MI,
    115                                unsigned SrcReg, bool isKill, int FrameIndex,
    116                                const TargetRegisterClass *RC,
    117                                const TargetRegisterInfo *TRI,
    118                                int64_t Offset) const = 0;
    119 
    120   virtual void loadRegFromStack(MachineBasicBlock &MBB,
    121                                 MachineBasicBlock::iterator MI,
    122                                 unsigned DestReg, int FrameIndex,
    123                                 const TargetRegisterClass *RC,
    124                                 const TargetRegisterInfo *TRI,
    125                                 int64_t Offset) const = 0;
    126 
    127   virtual void adjustStackPtr(unsigned SP, int64_t Amount,
    128                               MachineBasicBlock &MBB,
    129                               MachineBasicBlock::iterator I) const = 0;
    130 
    131   /// Create an instruction which has the same operands and memory operands
    132   /// as MI but has a new opcode.
    133   MachineInstrBuilder genInstrWithNewOpc(unsigned NewOpc,
    134                                          MachineBasicBlock::iterator I) const;
    135 
    136 protected:
    137   bool isZeroImm(const MachineOperand &op) const;
    138 
    139   MachineMemOperand *GetMemOperand(MachineBasicBlock &MBB, int FI,
    140                                    unsigned Flag) const;
    141 
    142 private:
    143   virtual unsigned getAnalyzableBrOpc(unsigned Opc) const = 0;
    144 
    145   void AnalyzeCondBr(const MachineInstr *Inst, unsigned Opc,
    146                      MachineBasicBlock *&BB,
    147                      SmallVectorImpl<MachineOperand> &Cond) const;
    148 
    149   void BuildCondBr(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
    150                    const DebugLoc &DL, ArrayRef<MachineOperand> Cond) const;
    151 };
    152 
    153 /// Create MipsInstrInfo objects.
    154 const MipsInstrInfo *createMips16InstrInfo(const MipsSubtarget &STI);
    155 const MipsInstrInfo *createMipsSEInstrInfo(const MipsSubtarget &STI);
    156 
    157 }
    158 
    159 #endif
    160