示例#1
0
文件: cpu.c 项目: alistair23/qemu
/* CPUClass::reset() */
static void m68k_cpu_reset(CPUState *s)
{
    M68kCPU *cpu = M68K_CPU(s);
    M68kCPUClass *mcc = M68K_CPU_GET_CLASS(cpu);
    CPUM68KState *env = &cpu->env;
    floatx80 nan = floatx80_default_nan(NULL);
    int i;

    mcc->parent_reset(s);

    memset(env, 0, offsetof(CPUM68KState, end_reset_fields));
#ifdef CONFIG_SOFTMMU
    cpu_m68k_set_sr(env, SR_S | SR_I);
#else
    cpu_m68k_set_sr(env, 0);
#endif
    for (i = 0; i < 8; i++) {
        env->fregs[i].d = nan;
    }
    cpu_m68k_set_fpcr(env, 0);
    env->fpsr = 0;

    /* TODO: We should set PC from the interrupt vector.  */
    env->pc = 0;
}
示例#2
0
文件: softfloat.c 项目: nikunjad/qemu
static floatx80 propagateFloatx80NaNOneArg(floatx80 a, float_status *status)
{
    if (floatx80_is_signaling_nan(a, status)) {
        float_raise(float_flag_invalid, status);
    }

    if (status->default_nan_mode) {
        return floatx80_default_nan(status);
    }

    return floatx80_maybe_silence_nan(a, status);
}
示例#3
0
文件: softfloat.c 项目: nikunjad/qemu
floatx80 floatx80_mod(floatx80 a, floatx80 b, float_status *status)
{
    flag aSign, zSign;
    int32_t aExp, bExp, expDiff;
    uint64_t aSig0, aSig1, bSig;
    uint64_t qTemp, term0, term1;

    aSig0 = extractFloatx80Frac(a);
    aExp = extractFloatx80Exp(a);
    aSign = extractFloatx80Sign(a);
    bSig = extractFloatx80Frac(b);
    bExp = extractFloatx80Exp(b);

    if (aExp == 0x7FFF) {
        if ((uint64_t) (aSig0 << 1)
            || ((bExp == 0x7FFF) && (uint64_t) (bSig << 1))) {
            return propagateFloatx80NaN(a, b, status);
        }
        goto invalid;
    }
    if (bExp == 0x7FFF) {
        if ((uint64_t) (bSig << 1)) {
            return propagateFloatx80NaN(a, b, status);
        }
        return a;
    }
    if (bExp == 0) {
        if (bSig == 0) {
        invalid:
            float_raise(float_flag_invalid, status);
            return floatx80_default_nan(status);
        }
        normalizeFloatx80Subnormal(bSig, &bExp, &bSig);
    }
    if (aExp == 0) {
        if ((uint64_t) (aSig0 << 1) == 0) {
            return a;
        }
        normalizeFloatx80Subnormal(aSig0, &aExp, &aSig0);
    }
    bSig |= LIT64(0x8000000000000000);
    zSign = aSign;
    expDiff = aExp - bExp;
    aSig1 = 0;
    if (expDiff < 0) {
        return a;
    }
    qTemp = (bSig <= aSig0);
    if (qTemp) {
        aSig0 -= bSig;
    }
    expDiff -= 64;
    while (0 < expDiff) {
        qTemp = estimateDiv128To64(aSig0, aSig1, bSig);
        qTemp = (2 < qTemp) ? qTemp - 2 : 0;
        mul64To128(bSig, qTemp, &term0, &term1);
        sub128(aSig0, aSig1, term0, term1, &aSig0, &aSig1);
        shortShift128Left(aSig0, aSig1, 62, &aSig0, &aSig1);
    }
    expDiff += 64;
    if (0 < expDiff) {
        qTemp = estimateDiv128To64(aSig0, aSig1, bSig);
        qTemp = (2 < qTemp) ? qTemp - 2 : 0;
        qTemp >>= 64 - expDiff;
        mul64To128(bSig, qTemp << (64 - expDiff), &term0, &term1);
        sub128(aSig0, aSig1, term0, term1, &aSig0, &aSig1);
        shortShift128Left(0, bSig, 64 - expDiff, &term0, &term1);
        while (le128(term0, term1, aSig0, aSig1)) {
            ++qTemp;
            sub128(aSig0, aSig1, term0, term1, &aSig0, &aSig1);
        }
    }