diff options
Diffstat (limited to 'arch/mips/math-emu/sp_tlong.c')
-rw-r--r-- | arch/mips/math-emu/sp_tlong.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/arch/mips/math-emu/sp_tlong.c b/arch/mips/math-emu/sp_tlong.c new file mode 100644 index 0000000..4be21aa --- /dev/null +++ b/arch/mips/math-emu/sp_tlong.c @@ -0,0 +1,123 @@ +/* IEEE754 floating point arithmetic + * single precision + */ +/* + * MIPS floating point support + * Copyright (C) 1994-2000 Algorithmics Ltd. + * http://www.algor.co.uk + * + * ######################################################################## + * + * 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., + * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. + * + * ######################################################################## + */ + + +#include "ieee754sp.h" + +s64 ieee754sp_tlong(ieee754sp x) +{ + COMPXDP; /* <-- need 64-bit mantissa tmp */ + + CLEARCX; + + EXPLODEXSP; + FLUSHXSP; + + switch (xc) { + case IEEE754_CLASS_SNAN: + case IEEE754_CLASS_QNAN: + case IEEE754_CLASS_INF: + SETCX(IEEE754_INVALID_OPERATION); + return ieee754di_xcpt(ieee754di_indef(), "sp_tlong", x); + case IEEE754_CLASS_ZERO: + return 0; + case IEEE754_CLASS_DNORM: + case IEEE754_CLASS_NORM: + break; + } + if (xe >= 63) { + /* look for valid corner case */ + if (xe == 63 && xs && xm == SP_HIDDEN_BIT) + return -0x8000000000000000LL; + /* Set invalid. We will only use overflow for floating + point overflow */ + SETCX(IEEE754_INVALID_OPERATION); + return ieee754di_xcpt(ieee754di_indef(), "sp_tlong", x); + } + /* oh gawd */ + if (xe > SP_MBITS) { + xm <<= xe - SP_MBITS; + } else if (xe < SP_MBITS) { + u32 residue; + int round; + int sticky; + int odd; + + if (xe < -1) { + residue = xm; + round = 0; + sticky = residue != 0; + xm = 0; + } + else { + residue = xm << (32 - SP_MBITS + xe); + round = (residue >> 31) != 0; + sticky = (residue << 1) != 0; + xm >>= SP_MBITS - xe; + } + odd = (xm & 0x1) != 0x0; + switch (ieee754_csr.rm) { + case IEEE754_RN: + if (round && (sticky || odd)) + xm++; + break; + case IEEE754_RZ: + break; + case IEEE754_RU: /* toward +Infinity */ + if ((round || sticky) && !xs) + xm++; + break; + case IEEE754_RD: /* toward -Infinity */ + if ((round || sticky) && xs) + xm++; + break; + } + if ((xm >> 63) != 0) { + /* This can happen after rounding */ + SETCX(IEEE754_INVALID_OPERATION); + return ieee754di_xcpt(ieee754di_indef(), "sp_tlong", x); + } + if (round || sticky) + SETCX(IEEE754_INEXACT); + } + if (xs) + return -xm; + else + return xm; +} + + +u64 ieee754sp_tulong(ieee754sp x) +{ + ieee754sp hb = ieee754sp_1e63(); + + /* what if x < 0 ?? */ + if (ieee754sp_lt(x, hb)) + return (u64) ieee754sp_tlong(x); + + return (u64) ieee754sp_tlong(ieee754sp_sub(x, hb)) | + (1ULL << 63); +} |