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#include <stdbool.h>
#include <stdint.h>
#include "platform.h"
#include "primitives.h"
#include "internals.h"
#include "specialize.h"
#include "softfloat.h"
float64_t f64_div( float64_t a, float64_t b )
{
union ui64_f64 uA;
uint_fast64_t uiA;
bool signA;
int_fast16_t expA;
uint_fast64_t sigA;
union ui64_f64 uB;
uint_fast64_t uiB;
bool signB;
int_fast16_t expB;
uint_fast64_t sigB;
bool signZ;
struct exp16_sig64 normExpSig;
int_fast16_t expZ;
uint_fast64_t sigZ;
struct uint128 term, rem;
uint_fast64_t uiZ;
union ui64_f64 uZ;
uA.f = a;
uiA = uA.ui;
signA = signF64UI( uiA );
expA = expF64UI( uiA );
sigA = fracF64UI( uiA );
uB.f = b;
uiB = uB.ui;
signB = signF64UI( uiB );
expB = expF64UI( uiB );
sigB = fracF64UI( uiB );
signZ = signA ^ signB;
if ( expA == 0x7FF ) {
if ( sigA ) goto propagateNaN;
if ( expB == 0x7FF ) {
if ( sigB ) goto propagateNaN;
goto invalid;
}
goto infinity;
}
if ( expB == 0x7FF ) {
if ( sigB ) goto propagateNaN;
goto zero;
}
if ( ! expB ) {
if ( ! sigB ) {
if ( ! ( expA | sigA ) ) goto invalid;
softfloat_raiseFlags( softfloat_flag_infinity );
goto infinity;
}
normExpSig = softfloat_normSubnormalF64Sig( sigB );
expB = normExpSig.exp;
sigB = normExpSig.sig;
}
if ( ! expA ) {
if ( ! sigA ) goto zero;
normExpSig = softfloat_normSubnormalF64Sig( sigA );
expA = normExpSig.exp;
sigA = normExpSig.sig;
}
expZ = expA - expB + 0x3FD;
sigA = ( sigA | UINT64_C( 0x0010000000000000 ) )<<10;
sigB = ( sigB | UINT64_C( 0x0010000000000000 ) )<<11;
if ( sigB <= ( sigA + sigA ) ) {
++expZ;
sigA >>= 1;
}
sigZ = softfloat_estimateDiv128To64( sigA, 0, sigB );
if ( ( sigZ & 0x1FF ) <= 2 ) {
term = softfloat_mul64To128( sigB, sigZ );
rem = softfloat_sub128( sigA, 0, term.v64, term.v0 );
while ( UINT64_C( 0x8000000000000000 ) <= rem.v64 ) {
--sigZ;
rem = softfloat_add128( rem.v64, rem.v0, 0, sigB );
}
sigZ |= ( rem.v0 != 0 );
}
return softfloat_roundPackToF64( signZ, expZ, sigZ );
propagateNaN:
uiZ = softfloat_propagateNaNF64UI( uiA, uiB );
goto uiZ;
invalid:
softfloat_raiseFlags( softfloat_flag_invalid );
uiZ = defaultNaNF64UI;
goto uiZ;
infinity:
uiZ = packToF64UI( signZ, 0x7FF, 0 );
goto uiZ;
zero:
uiZ = packToF64UI( signZ, 0, 0 );
uiZ:
uZ.ui = uiZ;
return uZ.f;
}
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