xref: /gem5/src/arch/generic/decode_cache.cc

/*
 * Copyright (c) 2011-2012 Google
 * 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
 */

#include "arch/generic/decode_cache.hh"
#include "arch/decoder.hh"
#include "arch/types.hh"
#include "config/the_isa.hh"
#include "cpu/static_inst.hh"

namespace GenericISA
{

StaticInstPtr
BasicDecodeCache::decode(TheISA::Decoder *decoder,
        TheISA::ExtMachInst mach_inst, Addr addr)
{
    StaticInstPtr &si = decodePages.lookup(addr);
    if (si && (si->machInst == mach_inst))
        return si;

    DecodeCache::InstMap::iterator iter = instMap.find(mach_inst);
    if (iter != instMap.end()) {
        si = iter->second;
        return si;
    }

    si = decoder->decodeInst(mach_inst);
    instMap[mach_inst] = si;
    return si;
}

} // namespace GenericISA