diff options
Diffstat (limited to 'kernel/arch/mips/math-emu/dp_fsp.c')
-rw-r--r-- | kernel/arch/mips/math-emu/dp_fsp.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/kernel/arch/mips/math-emu/dp_fsp.c b/kernel/arch/mips/math-emu/dp_fsp.c new file mode 100644 index 000000000..57d09ca54 --- /dev/null +++ b/kernel/arch/mips/math-emu/dp_fsp.c @@ -0,0 +1,75 @@ +/* IEEE754 floating point arithmetic + * double precision: common utilities + */ +/* + * MIPS floating point support + * Copyright (C) 1994-2000 Algorithmics Ltd. + * + * This program is free software; you can distribute it and/or modify it + * under the terms of the GNU General Public License (Version 2) as + * published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include "ieee754sp.h" +#include "ieee754dp.h" + +static inline union ieee754dp ieee754dp_nan_fsp(int xs, u64 xm) +{ + return builddp(xs, DP_EMAX + 1 + DP_EBIAS, + xm << (DP_FBITS - SP_FBITS)); +} + +union ieee754dp ieee754dp_fsp(union ieee754sp x) +{ + COMPXSP; + + EXPLODEXSP; + + ieee754_clearcx(); + + FLUSHXSP; + + switch (xc) { + case IEEE754_CLASS_SNAN: + return ieee754dp_nanxcpt(ieee754dp_nan_fsp(xs, xm)); + + case IEEE754_CLASS_QNAN: + return ieee754dp_nan_fsp(xs, xm); + + case IEEE754_CLASS_INF: + return ieee754dp_inf(xs); + + case IEEE754_CLASS_ZERO: + return ieee754dp_zero(xs); + + case IEEE754_CLASS_DNORM: + /* normalize */ + while ((xm >> SP_FBITS) == 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_FBITS - SP_FBITS)); +} |