haraldwolff/qemu-patch-raspberry4
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity

softfloat: Convert floatx80_div to FloatParts

Browse source 
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2020-11-21 12:44:47 -08:00
parent 153f664a74
commit 38db99e282
1 changed files with 13 additions and 87 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

100
fpu/softfloat.c
View file

@ -2294,6 +2294,19 @@ float128_div(float128 a, float128 b, float_status *status)
return float128_round_pack_canonical(pr, status);
}
floatx80 floatx80_div(floatx80 a, floatx80 b, float_status *status)
{
FloatParts128 pa, pb, *pr;
if (!floatx80_unpack_canonical(&pa, a, status) ||
!floatx80_unpack_canonical(&pb, b, status)) {
return floatx80_default_nan(status);
}
pr = parts_div(&pa, &pb, status);
return floatx80_round_pack_canonical(pr, status);
}
/*
* Float to Float conversions
*
@ -5877,93 +5890,6 @@ floatx80 floatx80_round_to_int(floatx80 a, float_status *status)
}
/*----------------------------------------------------------------------------
| Returns the result of dividing the extended double-precision floating-point
| value `a' by the corresponding value `b'. The operation is performed
| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic.
*----------------------------------------------------------------------------*/
floatx80 floatx80_div(floatx80 a, floatx80 b, float_status *status)
{
bool aSign, bSign, zSign;
int32_t aExp, bExp, zExp;
uint64_t aSig, bSig, zSig0, zSig1;
uint64_t rem0, rem1, rem2, term0, term1, term2;
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
float_raise(float_flag_invalid, status);
return floatx80_default_nan(status);
}
aSig = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );
bSig = extractFloatx80Frac( b );
bExp = extractFloatx80Exp( b );
bSign = extractFloatx80Sign( b );
zSign = aSign ^ bSign;
if ( aExp == 0x7FFF ) {
if ((uint64_t)(aSig << 1)) {
return propagateFloatx80NaN(a, b, status);
}
if ( bExp == 0x7FFF ) {
if ((uint64_t)(bSig << 1)) {
return propagateFloatx80NaN(a, b, status);
}
goto invalid;
}
return packFloatx80(zSign, floatx80_infinity_high,
floatx80_infinity_low);
}
if ( bExp == 0x7FFF ) {
if ((uint64_t)(bSig << 1)) {
return propagateFloatx80NaN(a, b, status);
}
return packFloatx80( zSign, 0, 0 );
}
if ( bExp == 0 ) {
if ( bSig == 0 ) {
if ( ( aExp | aSig ) == 0 ) {
invalid:
float_raise(float_flag_invalid, status);
return floatx80_default_nan(status);
}
float_raise(float_flag_divbyzero, status);
return packFloatx80(zSign, floatx80_infinity_high,
floatx80_infinity_low);
}
normalizeFloatx80Subnormal( bSig, &bExp, &bSig );
}
if ( aExp == 0 ) {
if ( aSig == 0 ) return packFloatx80( zSign, 0, 0 );
normalizeFloatx80Subnormal( aSig, &aExp, &aSig );
}
zExp = aExp - bExp + 0x3FFE;
rem1 = 0;
if ( bSig <= aSig ) {
shift128Right( aSig, 0, 1, &aSig, &rem1 );
++zExp;
}
zSig0 = estimateDiv128To64( aSig, rem1, bSig );
mul64To128( bSig, zSig0, &term0, &term1 );
sub128( aSig, rem1, term0, term1, &rem0, &rem1 );
while ( (int64_t) rem0 < 0 ) {
--zSig0;
add128( rem0, rem1, 0, bSig, &rem0, &rem1 );
}
zSig1 = estimateDiv128To64( rem1, 0, bSig );
if ( (uint64_t) ( zSig1<<1 ) <= 8 ) {
mul64To128( bSig, zSig1, &term1, &term2 );
sub128( rem1, 0, term1, term2, &rem1, &rem2 );
while ( (int64_t) rem1 < 0 ) {
--zSig1;
add128( rem1, rem2, 0, bSig, &rem1, &rem2 );
}
zSig1 |= ( ( rem1 | rem2 ) != 0 );
}
return roundAndPackFloatx80(status->floatx80_rounding_precision,
zSign, zExp, zSig0, zSig1, status);
}
/*----------------------------------------------------------------------------
| Returns the remainder of the extended double-precision floating-point value
| `a' with respect to the corresponding value `b'. The operation is performed