decoder.hh

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/*
 * Copyright 2020 Google, Inc.
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 * modification, are permitted provided that the following conditions are
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 * notice, this list of conditions and the following disclaimer;
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 * neither the name of the copyright holders nor the names of its
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 * this software without specific prior written permission.
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#ifndef __ARCH_GENERIC_DECODER_HH__
#define __ARCH_GENERIC_DECODER_HH__
 
#include "base/bitfield.hh"
#include "base/intmath.hh"
#include "base/types.hh"
#include "cpu/static_inst_fwd.hh"
 
namespace gem5
{
 
class InstDecoder
{
  protected:
    void *_moreBytesPtr;
    size_t _moreBytesSize;
    Addr _pcMask;
 
  public:
    template <typename MoreBytesType>
    InstDecoder(MoreBytesType *mb_buf) :
        _moreBytesPtr(mb_buf), _moreBytesSize(sizeof(MoreBytesType)),
        _pcMask(~mask(floorLog2(_moreBytesSize)))
    {}
 
    virtual StaticInstPtr fetchRomMicroop(
            MicroPC micropc, StaticInstPtr curMacroop);
 
    void *moreBytesPtr() const { return _moreBytesPtr; }
    size_t moreBytesSize() const { return _moreBytesSize; }
    Addr pcMask() const { return _pcMask; }
};
 
} // namespace gem5
 
#endif // __ARCH_DECODER_GENERIC_HH__