14604Sgblack@eecs.umich.edu/*
24604Sgblack@eecs.umich.edu * Copyright (c) 2007 The Hewlett-Packard Development Company
34604Sgblack@eecs.umich.edu * All rights reserved.
44604Sgblack@eecs.umich.edu *
57087Snate@binkert.org * The license below extends only to copyright in the software and shall
67087Snate@binkert.org * not be construed as granting a license to any other intellectual
77087Snate@binkert.org * property including but not limited to intellectual property relating
87087Snate@binkert.org * to a hardware implementation of the functionality of the software
97087Snate@binkert.org * licensed hereunder.  You may use the software subject to the license
107087Snate@binkert.org * terms below provided that you ensure that this notice is replicated
117087Snate@binkert.org * unmodified and in its entirety in all distributions of the software,
127087Snate@binkert.org * modified or unmodified, in source code or in binary form.
134604Sgblack@eecs.umich.edu *
147087Snate@binkert.org * Redistribution and use in source and binary forms, with or without
157087Snate@binkert.org * modification, are permitted provided that the following conditions are
167087Snate@binkert.org * met: redistributions of source code must retain the above copyright
177087Snate@binkert.org * notice, this list of conditions and the following disclaimer;
187087Snate@binkert.org * redistributions in binary form must reproduce the above copyright
197087Snate@binkert.org * notice, this list of conditions and the following disclaimer in the
207087Snate@binkert.org * documentation and/or other materials provided with the distribution;
217087Snate@binkert.org * neither the name of the copyright holders nor the names of its
224604Sgblack@eecs.umich.edu * contributors may be used to endorse or promote products derived from
237087Snate@binkert.org * this software without specific prior written permission.
244604Sgblack@eecs.umich.edu *
254604Sgblack@eecs.umich.edu * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
264604Sgblack@eecs.umich.edu * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
274604Sgblack@eecs.umich.edu * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
284604Sgblack@eecs.umich.edu * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
294604Sgblack@eecs.umich.edu * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
304604Sgblack@eecs.umich.edu * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
314604Sgblack@eecs.umich.edu * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
324604Sgblack@eecs.umich.edu * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
334604Sgblack@eecs.umich.edu * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
344604Sgblack@eecs.umich.edu * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
354604Sgblack@eecs.umich.edu * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
364604Sgblack@eecs.umich.edu *
374604Sgblack@eecs.umich.edu * Authors: Gabe Black
384604Sgblack@eecs.umich.edu */
394604Sgblack@eecs.umich.edu
4011793Sbrandon.potter@amd.com#include "arch/x86/emulenv.hh"
4111793Sbrandon.potter@amd.com
425616Snate@binkert.org#include <cassert>
435616Snate@binkert.org
4412334Sgabeblack@google.com#include "base/logging.hh"
454604Sgblack@eecs.umich.edu
464604Sgblack@eecs.umich.eduusing namespace X86ISA;
474604Sgblack@eecs.umich.edu
484604Sgblack@eecs.umich.eduvoid EmulEnv::doModRM(const ExtMachInst & machInst)
494604Sgblack@eecs.umich.edu{
504604Sgblack@eecs.umich.edu    assert(machInst.modRM.mod != 3);
514604Sgblack@eecs.umich.edu    //Use the SIB byte for addressing if the modrm byte calls for it.
524604Sgblack@eecs.umich.edu    if (machInst.modRM.rm == 4 && machInst.addrSize != 2) {
534604Sgblack@eecs.umich.edu        scale = 1 << machInst.sib.scale;
544712Sgblack@eecs.umich.edu        index = machInst.sib.index | (machInst.rex.x << 3);
554712Sgblack@eecs.umich.edu        base = machInst.sib.base | (machInst.rex.b << 3);
564604Sgblack@eecs.umich.edu        //In this special case, we don't use a base. The displacement also
579023Sgblack@eecs.umich.edu        //changes, but that's managed by the decoder.
584604Sgblack@eecs.umich.edu        if (machInst.sib.base == INTREG_RBP && machInst.modRM.mod == 0)
594604Sgblack@eecs.umich.edu            base = NUM_INTREGS;
604604Sgblack@eecs.umich.edu        //In -this- special case, we don't use an index.
614848Sgblack@eecs.umich.edu        if (index == INTREG_RSP)
624604Sgblack@eecs.umich.edu            index = NUM_INTREGS;
634604Sgblack@eecs.umich.edu    } else {
644604Sgblack@eecs.umich.edu        if (machInst.addrSize == 2) {
656071Sgblack@eecs.umich.edu            unsigned rm = machInst.modRM.rm;
666071Sgblack@eecs.umich.edu            if (rm <= 3) {
676071Sgblack@eecs.umich.edu                scale = 1;
686071Sgblack@eecs.umich.edu                if (rm < 2) {
696071Sgblack@eecs.umich.edu                    base = INTREG_RBX;
706071Sgblack@eecs.umich.edu                } else {
716071Sgblack@eecs.umich.edu                    base = INTREG_RBP;
726071Sgblack@eecs.umich.edu                }
736071Sgblack@eecs.umich.edu                index = (rm % 2) ? INTREG_RDI : INTREG_RSI;
746071Sgblack@eecs.umich.edu            } else {
756071Sgblack@eecs.umich.edu                scale = 0;
766071Sgblack@eecs.umich.edu                switch (rm) {
776071Sgblack@eecs.umich.edu                  case 4:
786071Sgblack@eecs.umich.edu                    base = INTREG_RSI;
796071Sgblack@eecs.umich.edu                    break;
806071Sgblack@eecs.umich.edu                  case 5:
816071Sgblack@eecs.umich.edu                    base = INTREG_RDI;
826071Sgblack@eecs.umich.edu                    break;
836071Sgblack@eecs.umich.edu                  case 6:
846071Sgblack@eecs.umich.edu                    base = INTREG_RBP;
856071Sgblack@eecs.umich.edu                    break;
866071Sgblack@eecs.umich.edu                  case 7:
876071Sgblack@eecs.umich.edu                    base = INTREG_RBX;
886071Sgblack@eecs.umich.edu                    break;
896071Sgblack@eecs.umich.edu                }
906071Sgblack@eecs.umich.edu            }
914604Sgblack@eecs.umich.edu        } else {
924604Sgblack@eecs.umich.edu            scale = 0;
934712Sgblack@eecs.umich.edu            base = machInst.modRM.rm | (machInst.rex.b << 3);
944604Sgblack@eecs.umich.edu            if (machInst.modRM.mod == 0 && machInst.modRM.rm == 5) {
954712Sgblack@eecs.umich.edu                //Since we need to use a different encoding of this
964712Sgblack@eecs.umich.edu                //instruction anyway, just ignore the base in those cases
974848Sgblack@eecs.umich.edu                base = NUM_INTREGS;
984604Sgblack@eecs.umich.edu            }
994604Sgblack@eecs.umich.edu        }
1004604Sgblack@eecs.umich.edu    }
1014863Sgblack@eecs.umich.edu    //Figure out what segment to use. This won't be entirely accurate since
1024863Sgblack@eecs.umich.edu    //the presence of a displacement is supposed to make the instruction
1034863Sgblack@eecs.umich.edu    //default to the data segment.
1046437Sgblack@eecs.umich.edu    if ((base != INTREG_RBP && base != INTREG_RSP) || machInst.dispSize) {
1054863Sgblack@eecs.umich.edu        seg = SEGMENT_REG_DS;
1064863Sgblack@eecs.umich.edu        //Handle any segment override that might have been in the instruction
1074863Sgblack@eecs.umich.edu        int segFromInst = machInst.legacy.seg;
1084863Sgblack@eecs.umich.edu        if (segFromInst)
1094863Sgblack@eecs.umich.edu            seg = (SegmentRegIndex)(segFromInst - 1);
1104863Sgblack@eecs.umich.edu    } else {
1114863Sgblack@eecs.umich.edu        seg = SEGMENT_REG_SS;
1124863Sgblack@eecs.umich.edu    }
1134604Sgblack@eecs.umich.edu}
1144604Sgblack@eecs.umich.edu
1155966Sgblack@eecs.umich.eduvoid EmulEnv::setSeg(const ExtMachInst & machInst)
1165966Sgblack@eecs.umich.edu{
1175966Sgblack@eecs.umich.edu    seg = SEGMENT_REG_DS;
1185966Sgblack@eecs.umich.edu    //Handle any segment override that might have been in the instruction
1195966Sgblack@eecs.umich.edu    int segFromInst = machInst.legacy.seg;
1205966Sgblack@eecs.umich.edu    if (segFromInst)
1215966Sgblack@eecs.umich.edu        seg = (SegmentRegIndex)(segFromInst - 1);
1225966Sgblack@eecs.umich.edu}
123