gem5/src/arch/arm/isa/insts/ldr.isa

// -*- mode:c++ -*-

// Copyright (c) 2010 ARM Limited
// 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
// unmodified and in its entirety in all distributions of the software,
// modified or unmodified, in source code or in binary form.
//
// 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

let {{

    header_output = ""
    decoder_output = ""
    exec_output = ""

    def loadImmClassName(post, add, writeback, \
                         size=4, sign=False, user=False):
        return memClassName("LOAD_IMM", post, add, writeback,
                            size, sign, user)

    def loadRegClassName(post, add, writeback, \
                         size=4, sign=False, user=False):
        return memClassName("LOAD_REG", post, add, writeback,
                            size, sign, user)

    def loadDoubleImmClassName(post, add, writeback):
        return memClassName("LOAD_IMMD", post, add, writeback, 4, False, False)

    def loadDoubleRegClassName(post, add, writeback):
        return memClassName("LOAD_REGD", post, add, writeback, 4, False, False)

    def emitLoad(name, Name, imm, eaCode, accCode, \
                 memFlags, instFlags, base, double=False):
        global header_output, decoder_output, exec_output

        (newHeader,
         newDecoder,
         newExec) = loadStoreBase(name, Name, imm,
                                  eaCode, accCode, "",
                                  memFlags, instFlags, double, False,
                                  base, execTemplateBase = 'Load')

        header_output += newHeader
        decoder_output += newDecoder
        exec_output += newExec

    def buildImmLoad(mnem, post, add, writeback, \
                     size=4, sign=False, user=False, \
                     prefetch=False, ldrex=False):
        name = mnem
        Name = loadImmClassName(post, add, writeback, \
                                size, sign, user)

        if add:
            op = " +"
        else:
            op = " -"

        offset = op + " imm"
        eaCode = "EA = Base"
        if not post:
            eaCode += offset
        eaCode += ";"

        memFlags = ["ArmISA::TLB::MustBeOne", "%d" % (size - 1)]
        if prefetch:
            Name = "%s_%s" % (mnem.upper(), Name)
            memFlags.append("Request::PREFETCH")
            accCode = '''
            uint64_t temp = Mem%s;\n
            temp = temp;
            ''' % buildMemSuffix(sign, size)
        else:
            if ldrex:
                memFlags.append("Request::LLSC")
                Name = "%s_%s" % (mnem.upper(), Name)
            accCode = "IWDest = cSwap(Mem%s, ((CPSR)Cpsr).e);" % \
                buildMemSuffix(sign, size)

        if not prefetch and not ldrex:
            memFlags.append("ArmISA::TLB::AllowUnaligned")

        if writeback:
            accCode += "Base = Base %s;\n" % offset
        base = buildMemBase("MemoryImm", post, writeback)

        emitLoad(name, Name, True, eaCode, accCode, memFlags, [], base)

    def buildRfeLoad(mnem, post, add, writeback):
        name = mnem
        Name = "RFE_" + loadImmClassName(post, add, writeback, 8)

        offset = 0
        if post != add:
            offset += 4
        if not add:
            offset -= 8

        eaCode = "EA = Base + %d;" % offset

        wbDiff = -8
        if add:
            wbDiff = 8
        accCode = '''
        CPSR cpsr = Cpsr;
        NPC = cSwap<uint32_t>(Mem.ud, cpsr.e);
        uint32_t newCpsr =
            cpsrWriteByInstr(cpsr | CondCodes,
                             cSwap<uint32_t>(Mem.ud >> 32, cpsr.e),
                             0xF, true);
        Cpsr = ~CondCodesMask & newCpsr;
        CondCodes = CondCodesMask & newCpsr;
        '''
        if writeback:
            accCode += "Base = Base + %s;\n" % wbDiff

        global header_output, decoder_output, exec_output

        (newHeader,
         newDecoder,
         newExec) = RfeBase(name, Name, eaCode, accCode,
             ["ArmISA::TLB::AlignWord", "ArmISA::TLB::MustBeOne"], [])

        header_output += newHeader
        decoder_output += newDecoder
        exec_output += newExec

    def buildRegLoad(mnem, post, add, writeback, \
                     size=4, sign=False, user=False, prefetch=False):
        name = mnem
        Name = loadRegClassName(post, add, writeback,
                                size, sign, user)

        if add:
            op = " +"
        else:
            op = " -"

        offset = op + " shift_rm_imm(Index, shiftAmt," + \
                      " shiftType, CondCodes<29:>)"
        eaCode = "EA = Base"
        if not post:
            eaCode += offset
        eaCode += ";"

        memFlags = ["%d" % (size - 1), "ArmISA::TLB::MustBeOne"]
        if prefetch:
            Name = "%s_%s" % (mnem.upper(), Name)
            memFlags.append("Request::PREFETCH")
            accCode = '''
            uint64_t temp = Mem%s;\n
            temp = temp;
            ''' % buildMemSuffix(sign, size)
        else:
            accCode = "IWDest = cSwap(Mem%s, ((CPSR)Cpsr).e);" % \
                buildMemSuffix(sign, size)
        if writeback:
            accCode += "Base = Base %s;\n" % offset

        if not prefetch:
            memFlags.append("ArmISA::TLB::AllowUnaligned")

        base = buildMemBase("MemoryReg", post, writeback)

        emitLoad(name, Name, False, eaCode, accCode, \
                 memFlags, [], base)

    def buildDoubleImmLoad(mnem, post, add, writeback, ldrex=False):
        name = mnem
        Name = loadDoubleImmClassName(post, add, writeback)

        if add:
            op = " +"
        else:
            op = " -"

        offset = op + " imm"
        eaCode = "EA = Base"
        if not post:
            eaCode += offset
        eaCode += ";"

        accCode = '''
        CPSR cpsr = Cpsr;
        Dest = cSwap<uint32_t>(Mem.ud, cpsr.e);
        Dest2 = cSwap<uint32_t>(Mem.ud >> 32, cpsr.e);
        '''
        if ldrex:
            memFlags = ["Request::LLSC"]
            Name = "%s_%s" % (mnem.upper(), Name)
        else:
            memFlags = []
        if writeback:
            accCode += "Base = Base %s;\n" % offset
        base = buildMemBase("MemoryDImm", post, writeback)

        memFlags.extend(["ArmISA::TLB::MustBeOne",
                         "ArmISA::TLB::AlignWord"])

        emitLoad(name, Name, True, eaCode, accCode, \
                 memFlags, [], base, double=True)

    def buildDoubleRegLoad(mnem, post, add, writeback):
        name = mnem
        Name = loadDoubleRegClassName(post, add, writeback)

        if add:
            op = " +"
        else:
            op = " -"

        offset = op + " shift_rm_imm(Index, shiftAmt," + \
                      " shiftType, CondCodes<29:>)"
        eaCode = "EA = Base"
        if not post:
            eaCode += offset
        eaCode += ";"

        accCode = '''
        CPSR cpsr = Cpsr;
        Dest = cSwap<uint32_t>(Mem.ud, cpsr.e);
        Dest2 = cSwap<uint32_t>(Mem.ud >> 32, cpsr.e);
        '''
        if writeback:
            accCode += "Base = Base %s;\n" % offset
        base = buildMemBase("MemoryDReg", post, writeback)

        emitLoad(name, Name, False, eaCode, accCode,
                 ["ArmISA::TLB::MustBeOne", "ArmISA::TLB::AlignWord"],
                 [], base, double=True)

    def buildLoads(mnem, size=4, sign=False, user=False):
        buildImmLoad(mnem, True, True, True, size, sign, user)
        buildRegLoad(mnem, True, True, True, size, sign, user)
        buildImmLoad(mnem, True, False, True, size, sign, user)
        buildRegLoad(mnem, True, False, True, size, sign, user)
        buildImmLoad(mnem, False, True, True, size, sign, user)
        buildRegLoad(mnem, False, True, True, size, sign, user)
        buildImmLoad(mnem, False, False, True, size, sign, user)
        buildRegLoad(mnem, False, False, True, size, sign, user)
        buildImmLoad(mnem, False, True, False, size, sign, user)
        buildRegLoad(mnem, False, True, False, size, sign, user)
        buildImmLoad(mnem, False, False, False, size, sign, user)
        buildRegLoad(mnem, False, False, False, size, sign, user)

    def buildDoubleLoads(mnem):
        buildDoubleImmLoad(mnem, True, True, True)
        buildDoubleRegLoad(mnem, True, True, True)
        buildDoubleImmLoad(mnem, True, False, True)
        buildDoubleRegLoad(mnem, True, False, True)
        buildDoubleImmLoad(mnem, False, True, True)
        buildDoubleRegLoad(mnem, False, True, True)
        buildDoubleImmLoad(mnem, False, False, True)
        buildDoubleRegLoad(mnem, False, False, True)
        buildDoubleImmLoad(mnem, False, True, False)
        buildDoubleRegLoad(mnem, False, True, False)
        buildDoubleImmLoad(mnem, False, False, False)
        buildDoubleRegLoad(mnem, False, False, False)

    def buildRfeLoads(mnem):
        buildRfeLoad(mnem, True, True, True)
        buildRfeLoad(mnem, True, True, False)
        buildRfeLoad(mnem, True, False, True)
        buildRfeLoad(mnem, True, False, False)
        buildRfeLoad(mnem, False, True, True)
        buildRfeLoad(mnem, False, True, False)
        buildRfeLoad(mnem, False, False, True)
        buildRfeLoad(mnem, False, False, False)

    def buildPrefetches(mnem):
        buildRegLoad(mnem, False, False, False, size=1, prefetch=True)
        buildImmLoad(mnem, False, False, False, size=1, prefetch=True)
        buildRegLoad(mnem, False, True, False, size=1, prefetch=True)
        buildImmLoad(mnem, False, True, False, size=1, prefetch=True)

    buildLoads("ldr")
    buildLoads("ldrt", user=True)
    buildLoads("ldrb", size=1)
    buildLoads("ldrbt", size=1, user=True)
    buildLoads("ldrsb", size=1, sign=True)
    buildLoads("ldrsbt", size=1, sign=True, user=True)
    buildLoads("ldrh", size=2)
    buildLoads("ldrht", size=2, user=True)
    buildLoads("hdrsh", size=2, sign=True)
    buildLoads("ldrsht", size=2, sign=True, user=True)

    buildDoubleLoads("ldrd")

    buildRfeLoads("rfe")

    buildPrefetches("pld")
    buildPrefetches("pldw")
    buildPrefetches("pli")

    buildImmLoad("ldrex", False, True, False, size=4, ldrex=True)
    buildImmLoad("ldrexh", False, True, False, size=2, ldrex=True)
    buildImmLoad("ldrexb", False, True, False, size=1, ldrex=True)
    buildDoubleImmLoad("ldrexd", False, True, False, ldrex=True)
}};