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

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

// Copyright (c) 2010-2011,2019 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
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Authors: Gabe Black

let {{
    import math

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

    class LoadInst(LoadStoreInst):
        execBase = 'Load'

        def __init__(self, mnem, post, add, writeback,
                     size=4, sign=False, user=False, flavor="normal"):
            super(LoadInst, self).__init__()

            self.name = mnem
            self.post = post
            self.add = add
            self.writeback = writeback
            self.size = size
            self.sign = sign
            self.user = user
            self.flavor = flavor
            self.rasPop = False

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

            self.memFlags = ["ArmISA::TLB::MustBeOne"]
            self.codeBlobs = {"postacc_code" : ""}

        def emitHelper(self, base = 'Memory', wbDecl = None, instFlags = [], pcDecl = None):

            global header_output, decoder_output, exec_output

            codeBlobs = self.codeBlobs
            codeBlobs["predicate_test"] = pickPredicate(codeBlobs)
            (newHeader,
             newDecoder,
             newExec) = self.fillTemplates(self.name, self.Name, codeBlobs,
                                           self.memFlags, instFlags, base,
                                           wbDecl, pcDecl, self.rasPop,
                                           self.size, self.sign)

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

    class RfeInst(LoadInst):
        decConstBase = 'Rfe'

        def __init__(self, mnem, post, add, writeback):
            super(RfeInst, self).__init__(mnem, post, add, writeback)
            self.Name = "RFE_" + loadImmClassName(post, add, writeback, 8)

            self.memFlags.append("ArmISA::TLB::AlignWord")

        def emit(self):
            offset = 0
            if self.post != self.add:
                offset += 4
            if not self.add:
                offset -= 8
            self.codeBlobs["ea_code"] = "EA = Base + %d;" % offset

            wbDiff = -8
            if self.add:
                wbDiff = 8
            accCode = '''
            CPSR cpsr = Cpsr;
            cpsr.nz = CondCodesNZ;
            cpsr.c = CondCodesC;
            cpsr.v = CondCodesV;
            cpsr.ge = CondCodesGE;
            URc = cpsr;
            URa = cSwap<uint32_t>(Mem_ud, cpsr.e);
            URb = cSwap<uint32_t>(Mem_ud >> 32, cpsr.e);
            '''
            self.codeBlobs["memacc_code"] = accCode

            wbDecl = None
            pcDecl = "MicroUopSetPCCPSR(machInst, INTREG_UREG0, INTREG_UREG1, INTREG_UREG2);"

            if self.writeback:
                wbDecl = "MicroAddiUop(machInst, base, base, %d);" % wbDiff
            self.emitHelper('RfeOp', wbDecl, ["IsSerializeAfter", "IsNonSpeculative"], pcDecl)

    class LoadImmInst(LoadInst):
        def __init__(self, *args, **kargs):
            super(LoadImmInst, self).__init__(*args, **kargs)
            self.offset = self.op + " imm"

            if self.add:
                self.wbDecl = "MicroAddiUop(machInst, base, base, imm);"
            else:
                self.wbDecl = "MicroSubiUop(machInst, base, base, imm);"

            if self.add and self.post and self.writeback and not self.sign and \
               not self.user and self.size == 4:
                self.rasPop = True

    class LoadRegInst(LoadInst):
        def __init__(self, *args, **kargs):
            super(LoadRegInst, self).__init__(*args, **kargs)
            self.offset = self.op + " shift_rm_imm(Index, shiftAmt," + \
                                    " shiftType, OptShiftRmCondCodesC)"
            if self.add:
                 self.wbDecl = '''
                     MicroAddUop(machInst, base, base, wbIndexReg, shiftAmt, shiftType);
                 '''
            else:
                 self.wbDecl = '''
                     MicroSubUop(machInst, base, base, wbIndexReg, shiftAmt, shiftType);
                 '''

    class LoadSingle(LoadInst):
        def __init__(self, *args, **kargs):
            super(LoadSingle, self).__init__(*args, **kargs)

            # Build the default class name
            self.Name = self.nameFunc(self.post, self.add, self.writeback,
                                      self.size, self.sign, self.user)

            # Add memory request flags where necessary
            self.memFlags.append("%d" % int(math.log(self.size, 2)))
            if self.user:
                self.memFlags.append("ArmISA::TLB::UserMode")

            self.instFlags = []
            if self.flavor == "dprefetch":
                self.memFlags.append("Request::PREFETCH")
                self.instFlags = ['IsDataPrefetch']
            elif self.flavor == "iprefetch":
                self.memFlags.append("Request::PREFETCH")
                self.instFlags = ['IsInstPrefetch']
            elif self.flavor == "normal":
                self.memFlags.append("ArmISA::TLB::AllowUnaligned")

            if self.flavor in ("exclusive", "acex"):
                self.memFlags.append("Request::LLSC")

            if self.flavor in ("acquire", "acex"):
                self.instFlags.extend(["IsMemBarrier",
                                       "IsWriteBarrier",
                                       "IsReadBarrier"])

            # Disambiguate the class name for different flavors of loads
            if self.flavor != "normal":
                self.Name = "%s_%s" % (self.name.upper(), self.Name)

        def emit(self):
            # Address compuation code
            eaCode = "EA = Base"
            if not self.post:
                eaCode += self.offset
            eaCode += ";"

            if self.flavor == "fp":
                eaCode += vfpEnabledCheckCode

            self.codeBlobs["ea_code"] = eaCode

            # Code that actually handles the access
            if self.flavor == "dprefetch" or self.flavor == "iprefetch":
                accCode = 'uint64_t temp = Mem%s; temp = temp;'
            elif self.flavor == "fp":
                accCode = "FpDest_uw = cSwap(Mem%s, ((CPSR)Cpsr).e);\n"
            else:
                accCode = "IWDest = cSwap(Mem%s, ((CPSR)Cpsr).e);"
            accCode = accCode % buildMemSuffix(self.sign, self.size)

            self.codeBlobs["memacc_code"] = accCode

            # Push it out to the output files
            base = buildMemBase(self.basePrefix, self.post, self.writeback)
            wbDecl = None
            if self.writeback:
                wbDecl = self.wbDecl
            self.emitHelper(base, wbDecl, self.instFlags)

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

    class LoadImm(LoadImmInst, LoadSingle):
        decConstBase = 'LoadImm'
        basePrefix = 'MemoryImm'
        nameFunc = staticmethod(loadImmClassName)

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

    class LoadReg(LoadRegInst, LoadSingle):
        decConstBase = 'LoadReg'
        basePrefix = 'MemoryReg'
        nameFunc = staticmethod(loadRegClassName)

    class LoadDouble(LoadInst):
        def __init__(self, *args, **kargs):
            super(LoadDouble, self).__init__(*args, **kargs)

            # Build the default class name
            self.Name = self.nameFunc(self.post, self.add, self.writeback)

            self.instFlags = []
            # Add memory request flags where necessary
            if self.flavor in ("exclusive", "acex"):
                self.memFlags.append("Request::LLSC")
                self.memFlags.append("ArmISA::TLB::AlignDoubleWord")
            else:
                self.memFlags.append("ArmISA::TLB::AlignWord")

            # Disambiguate the class name for different flavors of loads
            if self.flavor != "normal":
                self.Name = "%s_%s" % (self.name.upper(), self.Name)

            if self.flavor in ("acquire", "acex"):
                self.instFlags.extend(["IsMemBarrier",
                                       "IsWriteBarrier",
                                       "IsReadBarrier"])

        def emit(self):
            # Address computation code
            eaCode = "EA = Base"
            if not self.post:
                eaCode += self.offset
            eaCode += ";"

            if self.flavor == "fp":
                eaCode += vfpEnabledCheckCode

            self.codeBlobs["ea_code"] = eaCode

            # Code that actually handles the access
            if self.flavor != "fp":
                accCode = '''
                CPSR cpsr = Cpsr;
                Dest = cSwap<uint32_t>(Mem_ud, cpsr.e);
                Dest2 = cSwap<uint32_t>(Mem_ud >> 32, cpsr.e);
                '''
            else:
                accCode = '''
                uint64_t swappedMem = cSwap(Mem_ud, ((CPSR)Cpsr).e);
                FpDest_uw = (uint32_t)swappedMem;
                FpDest2_uw = (uint32_t)(swappedMem >> 32);
                '''

            self.codeBlobs["memacc_code"] = accCode

            # Push it out to the output files
            base = buildMemBase(self.basePrefix, self.post, self.writeback)
            wbDecl = None
            if self.writeback:
                wbDecl = self.wbDecl
            self.emitHelper(base, wbDecl, self.instFlags)

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

    class LoadDoubleImm(LoadImmInst, LoadDouble):
        decConstBase = 'LoadStoreDImm'
        basePrefix = 'MemoryDImm'
        nameFunc = staticmethod(loadDoubleImmClassName)

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

    class LoadDoubleReg(LoadRegInst, LoadDouble):
        decConstBase = 'LoadDReg'
        basePrefix = 'MemoryDReg'
        nameFunc = staticmethod(loadDoubleRegClassName)

    def buildLoads(mnem, size=4, sign=False, user=False):
        LoadImm(mnem, True, True, True, size, sign, user).emit()
        LoadReg(mnem, True, True, True, size, sign, user).emit()
        LoadImm(mnem, True, False, True, size, sign, user).emit()
        LoadReg(mnem, True, False, True, size, sign, user).emit()
        LoadImm(mnem, False, True, True, size, sign, user).emit()
        LoadReg(mnem, False, True, True, size, sign, user).emit()
        LoadImm(mnem, False, False, True, size, sign, user).emit()
        LoadReg(mnem, False, False, True, size, sign, user).emit()
        LoadImm(mnem, False, True, False, size, sign, user).emit()
        LoadReg(mnem, False, True, False, size, sign, user).emit()
        LoadImm(mnem, False, False, False, size, sign, user).emit()
        LoadReg(mnem, False, False, False, size, sign, user).emit()

    def buildDoubleLoads(mnem):
        LoadDoubleImm(mnem, True, True, True).emit()
        LoadDoubleReg(mnem, True, True, True).emit()
        LoadDoubleImm(mnem, True, False, True).emit()
        LoadDoubleReg(mnem, True, False, True).emit()
        LoadDoubleImm(mnem, False, True, True).emit()
        LoadDoubleReg(mnem, False, True, True).emit()
        LoadDoubleImm(mnem, False, False, True).emit()
        LoadDoubleReg(mnem, False, False, True).emit()
        LoadDoubleImm(mnem, False, True, False).emit()
        LoadDoubleReg(mnem, False, True, False).emit()
        LoadDoubleImm(mnem, False, False, False).emit()
        LoadDoubleReg(mnem, False, False, False).emit()

    def buildRfeLoads(mnem):
        RfeInst(mnem, True, True, True).emit()
        RfeInst(mnem, True, True, False).emit()
        RfeInst(mnem, True, False, True).emit()
        RfeInst(mnem, True, False, False).emit()
        RfeInst(mnem, False, True, True).emit()
        RfeInst(mnem, False, True, False).emit()
        RfeInst(mnem, False, False, True).emit()
        RfeInst(mnem, False, False, False).emit()

    def buildPrefetches(mnem, type):
        LoadReg(mnem, False, False, False, size=1, flavor=type).emit()
        LoadImm(mnem, False, False, False, size=1, flavor=type).emit()
        LoadReg(mnem, False, True, False, size=1, flavor=type).emit()
        LoadImm(mnem, False, True, False, size=1, flavor=type).emit()

    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("ldrsh", size=2, sign=True)
    buildLoads("ldrsht", size=2, sign=True, user=True)

    buildDoubleLoads("ldrd")

    buildRfeLoads("rfe")

    buildPrefetches("pld", "dprefetch")
    buildPrefetches("pldw", "dprefetch")
    buildPrefetches("pli", "iprefetch")

    LoadImm("ldrex", False, True, False, size=4, flavor="exclusive").emit()
    LoadImm("ldrexh", False, True, False, size=2, flavor="exclusive").emit()
    LoadImm("ldrexb", False, True, False, size=1, flavor="exclusive").emit()
    LoadDoubleImm("ldrexd", False, True, False, flavor="exclusive").emit()

    LoadImm("lda", False, True, False, size=4, flavor="acquire").emit()
    LoadImm("ldah", False, True, False, size=2, flavor="acquire").emit()
    LoadImm("ldab", False, True, False, size=1, flavor="acquire").emit()
    LoadImm("ldaex", False, True, False, size=4, flavor="acex").emit()
    LoadImm("ldaexh", False, True, False, size=2, flavor="acex").emit()
    LoadImm("ldaexb", False, True, False, size=1, flavor="acex").emit()
    LoadDoubleImm("ldaexd", False, True, False, flavor="acex").emit()

    LoadImm("vldr", False, True, False, size=4, flavor="fp").emit()
    LoadImm("vldr", False, False, False, size=4, flavor="fp").emit()
    LoadDoubleImm("vldr", False, True, False, flavor="fp").emit()
    LoadDoubleImm("vldr", False, False, False, flavor="fp").emit()
}};