src/arch/x86/insts/microregop.cc

/*
 * Copyright (c) 2007 The Hewlett-Packard Development Company
 * All rights reserved.
 *
 * The license below extends only to copyright in the software and shall
 * not be construed as granting a license to any other intellectual
 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
 * licensed hereunder.  You may use the software subject to the license
 * terms below provided that you ensure that this notice is replicated
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 *
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 * 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
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 * 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
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#include "arch/x86/insts/microregop.hh"

#include <string>

#include "arch/x86/regs/misc.hh"
#include "base/condcodes.hh"
#include "debug/X86.hh"

namespace gem5
{

namespace X86ISA
{

uint64_t
RegOpBase::genFlags(uint64_t old_flags, uint64_t flag_mask,
        uint64_t _dest, uint64_t _src1, uint64_t _src2, bool subtract) const
{
    DPRINTF(X86, "flag_mask = %#x\n", flag_mask);
    uint64_t flags = old_flags & ~flag_mask;
    if (flag_mask & (ECFBit | CFBit)) {
        if (findCarry(dataSize*8, _dest, _src1, _src2))
            flags |= (flag_mask & (ECFBit | CFBit));
        if (subtract)
            flags ^= (flag_mask & (ECFBit | CFBit));
    }
    if (flag_mask & PFBit && !findParity(8, _dest))
        flags |= PFBit;
    if (flag_mask & AFBit) {
        if (findCarry(4, _dest, _src1, _src2))
            flags |= AFBit;
        if (subtract)
            flags ^= AFBit;
    }
    if (flag_mask & (EZFBit | ZFBit) && findZero(dataSize * 8, _dest))
        flags |= (flag_mask & (EZFBit | ZFBit));
    if (flag_mask & SFBit && findNegative(dataSize * 8, _dest))
        flags |= SFBit;
    if (flag_mask & OFBit && findOverflow(dataSize * 8, _dest, _src1, _src2))
        flags |= OFBit;
    return flags;
}

} // namespace X86ISA
} // namespace gem5