microregop.cc

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/*
 * Copyright (c) 2007 The Hewlett-Packard Development Company
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 *
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 * licensed hereunder.  You may use the software subject to the license
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 * met: redistributions of source code must retain the above copyright
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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