Function floatx80_mod

src/softfloat/softfloat.cpp:3000–3081

 *----------------------------------------------------------------------------*/

floatx80 floatx80_mod(floatx80 a, floatx80 b, uint64_t *q, flag *s, float_status *status)
{
    flag aSign, bSign, 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);
    bSign = extractFloatx80Sign(b);

    *s = 0;
    *q = 0;

    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);
        *s = (aSign != bSign);
        return normalizeRoundAndPackFloatx80(status->floatx80_rounding_precision, aSign, aExp, aSig0, 0, status);
    }
    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 (aSig0 == 0) {
            *s = (aSign != bSign);
            return a;
        }
        normalizeFloatx80Subnormal(aSig0, &aExp, &aSig0);
    }
    bSig |= LIT64(0x8000000000000000);
    zSign = aSign;
    expDiff = aExp - bExp;
    *s = (aSign != bSign);
    aSig1 = 0;
    if (expDiff < 0) return roundAndPackFloatx80(status->floatx80_rounding_precision, aSign, aExp, aSig0, 0, status);
    qTemp = (bSig <= aSig0);
    if (qTemp) aSig0 -= bSig;
    *q = (expDiff > 63) ? 0 : (qTemp << expDiff);
    expDiff -= 64;
    while (0 < expDiff) {
        qTemp = estimateDiv128To64(aSig0, aSig1, bSig);
        qTemp = (2 < qTemp) ? qTemp - 2 : 0;
        mul64To128(bSig, qTemp, &term0, &term1);