blob: 750321167ea29800fd88f9a1a44c3cbf1f17405a [file] [log] [blame]
/*
* Copyright (c) 2012 Google
* Copyright (c) 2017 The University of Virginia
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Gabe Black
* Alec Roelke
*/
#ifndef __ARCH_RISCV_DECODER_HH__
#define __ARCH_RISCV_DECODER_HH__
#include "arch/generic/decode_cache.hh"
#include "arch/riscv/isa_traits.hh"
#include "arch/riscv/types.hh"
#include "base/logging.hh"
#include "base/types.hh"
#include "cpu/static_inst.hh"
#include "debug/Decode.hh"
namespace RiscvISA
{
class ISA;
class Decoder
{
private:
DecodeCache::InstMap<ExtMachInst> instMap;
bool aligned;
bool mid;
bool more;
protected:
//The extended machine instruction being generated
ExtMachInst emi;
bool instDone;
public:
Decoder(ISA* isa=nullptr) { reset(); }
void process() {}
void reset();
inline bool compressed(ExtMachInst inst) { return (inst & 0x3) < 0x3; }
//Use this to give data to the decoder. This should be used
//when there is control flow.
void moreBytes(const PCState &pc, Addr fetchPC, MachInst inst);
bool needMoreBytes() { return more; }
bool instReady() { return instDone; }
void takeOverFrom(Decoder *old) {}
StaticInstPtr decodeInst(ExtMachInst mach_inst);
/// Decode a machine instruction.
/// @param mach_inst The binary instruction to decode.
/// @retval A pointer to the corresponding StaticInst object.
StaticInstPtr decode(ExtMachInst mach_inst, Addr addr);
StaticInstPtr decode(RiscvISA::PCState &nextPC);
};
} // namespace RiscvISA
#endif // __ARCH_RISCV_DECODER_HH__