original_kernel/arch/mips/math-emu/dp_simple.c

62 lines
1.5 KiB
C

/* 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 "ieee754dp.h"
union ieee754dp ieee754dp_neg(union ieee754dp x)
{
union ieee754dp y;
if (ieee754_csr.abs2008) {
y = x;
DPSIGN(y) = !DPSIGN(x);
} else {
unsigned int oldrm;
oldrm = ieee754_csr.rm;
ieee754_csr.rm = FPU_CSR_RD;
y = ieee754dp_sub(ieee754dp_zero(0), x);
ieee754_csr.rm = oldrm;
}
return y;
}
union ieee754dp ieee754dp_abs(union ieee754dp x)
{
union ieee754dp y;
if (ieee754_csr.abs2008) {
y = x;
DPSIGN(y) = 0;
} else {
unsigned int oldrm;
oldrm = ieee754_csr.rm;
ieee754_csr.rm = FPU_CSR_RD;
if (DPSIGN(x))
y = ieee754dp_sub(ieee754dp_zero(0), x);
else
y = ieee754dp_add(ieee754dp_zero(0), x);
ieee754_csr.rm = oldrm;
}
return y;
}