isa/insts/misc64.isa

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

// Copyright (c) 2011-2013, 2016-2018 ARM Limited
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// Authors: Gabe Black

let {{
    svcCode = '''
    fault = std::make_shared<SupervisorCall>(machInst, bits(machInst, 20, 5));
    '''

    svcIop = InstObjParams("svc", "Svc64", "ImmOp64",
                           svcCode, ["IsSyscall", "IsNonSpeculative",
                                     "IsSerializeAfter"])
    header_output = ImmOp64Declare.subst(svcIop)
    decoder_output = ImmOp64Constructor.subst(svcIop)
    exec_output = BasicExecute.subst(svcIop)

    hvcCode = '''
    SCR scr = Scr64;
    HCR hcr = Hcr64;
    CPSR cpsr = Cpsr;

    auto tc = xc->tcBase();
    ExceptionLevel pstate_EL = (ExceptionLevel)(uint8_t)(cpsr.el);

    bool unalloc_encod = !ArmSystem::haveEL(tc, EL2) || pstate_EL == EL0 ||
                         (pstate_EL == EL1 && inSecureState(tc));

    bool hvc_enable = ArmSystem::haveEL(tc, EL3) ?
        scr.hce : !hcr.hcd;

    if (unalloc_encod || !hvc_enable) {
        fault = undefinedFault64(tc, pstate_EL);
    } else {
        fault = std::make_shared<HypervisorCall>(machInst, bits(machInst, 20, 5));
    }
    '''

    hvcIop = InstObjParams("hvc", "Hvc64", "ImmOp64",
                           hvcCode, ["IsSyscall", "IsNonSpeculative",
                                     "IsSerializeAfter"])
    header_output += ImmOp64Declare.subst(hvcIop)
    decoder_output += ImmOp64Constructor.subst(hvcIop)
    exec_output += BasicExecute.subst(hvcIop)

    # @todo: extend to take into account Virtualization.
    smcCode = '''
    SCR scr = Scr64;
    CPSR cpsr = Cpsr;

    if (!ArmSystem::haveSecurity(xc->tcBase()) || inUserMode(cpsr) || scr.smd) {
        fault = disabledFault();
    } else {
        fault = std::make_shared<SecureMonitorCall>(machInst);
    }
    '''

    smcIop = InstObjParams("smc", "Smc64", "ImmOp64",
                           smcCode, ["IsNonSpeculative", "IsSerializeAfter"])
    header_output += ImmOp64Declare.subst(smcIop)
    decoder_output += ImmOp64Constructor.subst(smcIop)
    exec_output += BasicExecute.subst(smcIop)

    def subst(templateBase, iop):
        global header_output, decoder_output, exec_output
        header_output += eval(templateBase + "Declare").subst(iop)
        decoder_output += eval(templateBase + "Constructor").subst(iop)
        exec_output += BasicExecute.subst(iop)

    bfmMaskCode = '''
    uint64_t bitMask;
    int diff = imm2 - imm1;
    if (imm1 <= imm2) {
        bitMask = mask(diff + 1);
    } else {
        bitMask = mask(imm2 + 1);
        bitMask = (bitMask >> imm1) | (bitMask << (intWidth - imm1));
        diff += intWidth;
    }
    uint64_t topBits M5_VAR_USED = ~mask(diff+1);
    uint64_t result = imm1 == 0 ? Op164 :
                      (Op164 >> imm1) | (Op164 << (intWidth - imm1));
    result &= bitMask;
    '''

    bfmCode = bfmMaskCode + 'Dest64 = result | (Dest64 & ~bitMask);'
    bfmIop = InstObjParams("bfm", "Bfm64", "RegRegImmImmOp64", bfmCode);
    subst("RegRegImmImmOp64", bfmIop)

    ubfmCode = bfmMaskCode + 'Dest64 = result;'
    ubfmIop = InstObjParams("ubfm", "Ubfm64", "RegRegImmImmOp64", ubfmCode);
    subst("RegRegImmImmOp64", ubfmIop)

    sbfmCode = bfmMaskCode + \
        'Dest64 = result | (bits(Op164, imm2) ? topBits : 0);'
    sbfmIop = InstObjParams("sbfm", "Sbfm64", "RegRegImmImmOp64", sbfmCode);
    subst("RegRegImmImmOp64", sbfmIop)

    extrCode = '''
        if (imm == 0) {
            Dest64 = Op264;
        } else {
            Dest64 = (Op164 << (intWidth - imm)) | (Op264 >> imm);
        }
    '''
    extrIop = InstObjParams("extr", "Extr64", "RegRegRegImmOp64", extrCode);
    subst("RegRegRegImmOp64", extrIop);

    unknownCode = '''
            return std::make_shared<UndefinedInstruction>(machInst, true);
    '''
    unknown64Iop = InstObjParams("unknown", "Unknown64", "UnknownOp64",
                                 unknownCode)
    header_output += BasicDeclare.subst(unknown64Iop)
    decoder_output += BasicConstructor64.subst(unknown64Iop)
    exec_output += BasicExecute.subst(unknown64Iop)

    isbIop = InstObjParams("isb", "Isb64", "ArmStaticInst", "",
                           ['IsSquashAfter'])
    header_output += BasicDeclare.subst(isbIop)
    decoder_output += BasicConstructor64.subst(isbIop)
    exec_output += BasicExecute.subst(isbIop)

    dsbIop = InstObjParams("dsb", "Dsb64", "ArmStaticInst", "",
                           ['IsMemBarrier', 'IsSerializeAfter'])
    header_output += BasicDeclare.subst(dsbIop)
    decoder_output += BasicConstructor64.subst(dsbIop)
    exec_output += BasicExecute.subst(dsbIop)

    dmbIop = InstObjParams("dmb", "Dmb64", "ArmStaticInst", "",
                           ['IsMemBarrier'])
    header_output += BasicDeclare.subst(dmbIop)
    decoder_output += BasicConstructor64.subst(dmbIop)
    exec_output += BasicExecute.subst(dmbIop)

    clrexIop = InstObjParams("clrex", "Clrex64", "ArmStaticInst",
                             "LLSCLock = 0;")
    header_output += BasicDeclare.subst(clrexIop)
    decoder_output += BasicConstructor64.subst(clrexIop)
    exec_output += BasicExecute.subst(clrexIop)


    brkCode = '''
    fault = std::make_shared<SoftwareBreakpoint>(machInst,
                                                 bits(machInst, 20, 5));
    '''

    brkIop = InstObjParams("brk", "Brk64", "ImmOp64",
                           brkCode, ["IsSerializeAfter"])
    header_output += ImmOp64Declare.subst(brkIop)
    decoder_output += ImmOp64Constructor.subst(brkIop)
    exec_output += BasicExecute.subst(brkIop)

    hltCode = '''
    ThreadContext *tc = xc->tcBase();
    if (ArmSystem::haveSemihosting(tc) && imm == 0xF000) {
        X0 = ArmSystem::callSemihosting64(tc, X0 & mask(32), X1);
    } else {
        // HLT instructions aren't implemented, so treat them as undefined
        // instructions.
        fault = std::make_shared<UndefinedInstruction>(
            machInst, false, mnemonic);
    }

    '''

    hltIop = InstObjParams("hlt", "Hlt64", "ImmOp64",
                           hltCode, ["IsNonSpeculative"])
    header_output += ImmOp64Declare.subst(hltIop)
    decoder_output += SemihostConstructor64.subst(hltIop)
    exec_output += BasicExecute.subst(hltIop)
}};