lib/Target/Mips/MipsAnalyzeImmediate.h

//===-- MipsAnalyzeImmediate.h - Analyze immediates -----------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef MIPS_ANALYZE_IMMEDIATE_H
#define MIPS_ANALYZE_IMMEDIATE_H

#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/DataTypes.h"

namespace llvm {

  class MipsAnalyzeImmediate {
  public:
    struct Inst {
      unsigned Opc, ImmOpnd;
      Inst(unsigned Opc, unsigned ImmOpnd);
    };
    typedef SmallVector<Inst, 7 > InstSeq;

    /// Analyze - Get an instrucion sequence to load immediate Imm. The last
    /// instruction in the sequence must be an ADDiu if LastInstrIsADDiu is
    /// true;
    const InstSeq &Analyze(int64_t Imm, unsigned Size, bool LastInstrIsADDiu);
  private:
    typedef SmallVector<InstSeq, 5> InstSeqLs;

    /// AddInstr - Add I to all instruction sequences in SeqLs.
    void AddInstr(InstSeqLs &SeqLs, const Inst &I);

    /// GetInstSeqLsADDiu - Get instrucion sequences which end with an ADDiu to
    /// load immediate Imm
    void GetInstSeqLsADDiu(int64_t Imm, unsigned RemSize, InstSeqLs &SeqLs);

    /// GetInstSeqLsORi - Get instrucion sequences which end with an ORi to
    /// load immediate Imm
    void GetInstSeqLsORi(int64_t Imm, unsigned RemSize, InstSeqLs &SeqLs);

    /// GetInstSeqLsSLL - Get instrucion sequences which end with a SLL to
    /// load immediate Imm
    void GetInstSeqLsSLL(int64_t Imm, unsigned RemSize, InstSeqLs &SeqLs);

    /// GetInstSeqLs - Get instrucion sequences to load immediate Imm.
    void GetInstSeqLs(int64_t Imm, unsigned RemSize, InstSeqLs &SeqLs);

    /// ReplaceADDiuSLLWithLUi - Replace an ADDiu & SLL pair with a LUi.
    void ReplaceADDiuSLLWithLUi(InstSeq &Seq);

    /// GetShortestSeq - Find the shortest instruction sequence in SeqLs and
    /// return it in Insts. 
    void GetShortestSeq(InstSeqLs &SeqLs, InstSeq &Insts);

    unsigned Size;
    unsigned ADDiu, ORi, SLL, LUi;
    InstSeq Insts;
  };
}

#endif