Function floatx80_rem

src/softfloat/softfloat.cpp:2799–2890

#ifndef SOFTFLOAT_68K
floatx80 floatx80_rem(floatx80 a, floatx80 b, float_status *status)
{
    flag aSign, zSign;
    int32_t aExp, bExp, expDiff;
    uint64_t aSig0, aSig1, bSig;
    uint64_t q, term0, term1, alternateASig0, alternateASig1;

    if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
        float_raise(float_flag_invalid, status);
        return floatx80_default_nan(status);
    }
    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 ) {
        if ( expDiff < -1 ) return a;
        shift128Right( aSig0, 0, 1, &aSig0, &aSig1 );
        expDiff = 0;
    }
    q = ( bSig <= aSig0 );
    if ( q ) aSig0 -= bSig;
    expDiff -= 64;
    while ( 0 < expDiff ) {
        q = estimateDiv128To64( aSig0, aSig1, bSig );
        q = ( 2 < q ) ? q - 2 : 0;
        mul64To128( bSig, q, &term0, &term1 );
        sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 );