ieee754dp ieee754dp_abs(ieee754dp x)
{
COMPXDP;
EXPLODEXDP;
CLEARCX;
FLUSHXDP;
/* Clear sign ALWAYS, irrespective of NaN */
DPSIGN(x) = 0;
if (xc == IEEE754_CLASS_SNAN) {
return ieee754dp_nanxcpt(ieee754dp_indef(), "abs");
}
return x;
}
ieee754dp ieee754dp_fsp(ieee754sp x)
{
COMPXSP;
EXPLODEXSP;
CLEARCX;
FLUSHXSP;
switch (xc) {
case IEEE754_CLASS_SNAN:
SETCX(IEEE754_INVALID_OPERATION);
return ieee754dp_nanxcpt(ieee754dp_indef(), "fsp");
case IEEE754_CLASS_QNAN:
return ieee754dp_nanxcpt(builddp(xs,
DP_EMAX + 1 + DP_EBIAS,
((u64) xm
<< (DP_MBITS -
SP_MBITS))), "fsp",
x);
case IEEE754_CLASS_INF:
return ieee754dp_inf(xs);
case IEEE754_CLASS_ZERO:
return ieee754dp_zero(xs);
case IEEE754_CLASS_DNORM:
/* normalize */
while ((xm >> SP_MBITS) == 0) {
xm <<= 1;
xe--;
}
break;
case IEEE754_CLASS_NORM:
break;
}
/* CAN'T possibly overflow,underflow, or need rounding
*/
/* drop the hidden bit */
xm &= ~SP_HIDDEN_BIT;
return builddp(xs, xe + DP_EBIAS,
(u64) xm << (DP_MBITS - SP_MBITS));
}
ieee754dp ieee754dp_abs(ieee754dp x)
{
COMPXDP;
EXPLODEXDP;
CLEARCX;
FLUSHXDP;
DPSIGN(x) = 0;
if (xc == IEEE754_CLASS_SNAN) {
SETCX(IEEE754_INVALID_OPERATION);
return ieee754dp_nanxcpt(ieee754dp_indef(), "abs");
}
return x;
}
ieee754dp ieee754dp_fsp(ieee754sp x)
{
COMPXSP;
EXPLODEXSP;
CLEARCX;
FLUSHXSP;
switch (xc) {
case IEEE754_CLASS_SNAN:
SETCX(IEEE754_INVALID_OPERATION);
return ieee754dp_nanxcpt(ieee754dp_indef(), "fsp");
case IEEE754_CLASS_QNAN:
return ieee754dp_nanxcpt(builddp(xs,
DP_EMAX + 1 + DP_EBIAS,
((u64) xm
<< (DP_MBITS -
SP_MBITS))), "fsp",
x);
case IEEE754_CLASS_INF:
return ieee754dp_inf(xs);
case IEEE754_CLASS_ZERO:
return ieee754dp_zero(xs);
case IEEE754_CLASS_DNORM:
while ((xm >> SP_MBITS) == 0) {
xm <<= 1;
xe--;
}
break;
case IEEE754_CLASS_NORM:
break;
}
xm &= ~SP_HIDDEN_BIT;
return builddp(xs, xe + DP_EBIAS,
(u64) xm << (DP_MBITS - SP_MBITS));
}
ieee754dp ieee754dp_neg(ieee754dp x)
{
COMPXDP;
EXPLODEXDP;
CLEARCX;
FLUSHXDP;
DPSIGN(x) ^= 1;
if (xc == IEEE754_CLASS_SNAN) {
ieee754dp y = ieee754dp_indef();
SETCX(IEEE754_INVALID_OPERATION);
DPSIGN(y) = DPSIGN(x);
return ieee754dp_nanxcpt(y, "neg");
}
return x;
}
ieee754dp ieee754dp_neg(ieee754dp x)
{
COMPXDP;
EXPLODEXDP;
CLEARCX;
FLUSHXDP;
/*
* Invert the sign ALWAYS to prevent an endless recursion on
* pow() in libc.
*/
/* quick fix up */
DPSIGN(x) ^= 1;
if (xc == IEEE754_CLASS_SNAN) {
ieee754dp y = ieee754dp_indef();
SETCX(IEEE754_INVALID_OPERATION);
DPSIGN(y) = DPSIGN(x);
return ieee754dp_nanxcpt(y, "neg");
}
return x;
}
ieee754dp ieee754dp_div(ieee754dp x, ieee754dp y)
{
COMPXDP;
COMPYDP;
EXPLODEXDP;
EXPLODEYDP;
CLEARCX;
FLUSHXDP;
FLUSHYDP;
switch (CLPAIR(xc, yc)) {
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_SNAN):
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_SNAN):
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_SNAN):
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_SNAN):
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_SNAN):
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_SNAN):
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_NORM):
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_DNORM):
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):
SETCX(IEEE754_INVALID_OPERATION);
return ieee754dp_nanxcpt(ieee754dp_indef(), "div", x, y);
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN):
return y;
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM):
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM):
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_INF):
return x;
/* Infinity handling
*/
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
SETCX(IEEE754_INVALID_OPERATION);
return ieee754dp_xcpt(ieee754dp_indef(), "div", x, y);
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
return ieee754dp_zero(xs ^ ys);
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
return ieee754dp_inf(xs ^ ys);
/* Zero handling
*/
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
SETCX(IEEE754_INVALID_OPERATION);
return ieee754dp_xcpt(ieee754dp_indef(), "div", x, y);
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
SETCX(IEEE754_ZERO_DIVIDE);
return ieee754dp_xcpt(ieee754dp_inf(xs ^ ys), "div", x, y);
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
return ieee754dp_zero(xs == ys ? 0 : 1);
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
DPDNORMX;
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM):
DPDNORMY;
break;
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_NORM):
DPDNORMX;
break;
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_NORM):
break;
}
assert(xm & DP_HIDDEN_BIT);
assert(ym & DP_HIDDEN_BIT);
/* provide rounding space */
xm <<= 3;
ym <<= 3;
{
/* now the dirty work */
u64 rm = 0;
int re = xe - ye;
u64 bm;
for (bm = DP_MBIT(DP_MBITS + 2); bm; bm >>= 1) {
if (xm >= ym) {
xm -= ym;
rm |= bm;
if (xm == 0)
break;
}
xm <<= 1;
}
rm <<= 1;
if (xm)
rm |= 1; /* have remainder, set sticky */
assert(rm);
/* normalise rm to rounding precision ?
*/
while ((rm >> (DP_MBITS + 3)) == 0) {
rm <<= 1;
re--;
}
DPNORMRET2(xs == ys ? 0 : 1, re, rm, "div", x, y);
}
}
