diff options
Diffstat (limited to 'sysdeps/powerpc/q_lltoq.c')
-rw-r--r-- | sysdeps/powerpc/q_lltoq.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/sysdeps/powerpc/q_lltoq.c b/sysdeps/powerpc/q_lltoq.c new file mode 100644 index 0000000000..6222eff9fc --- /dev/null +++ b/sysdeps/powerpc/q_lltoq.c @@ -0,0 +1,52 @@ +/* 64-bit fixed point signed integer to 128-bit floating point. + Copyright (C) 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <quad_float.h> + +/* long double _q_ulltoq(long long a); + Convert 'a' to long double. + */ + +void +__q_lltoq(unsigned int result[4], long long a) +{ + unsigned rx; + int cs, css; + + /* Calculate absolute value of 'a'. */ + unsigned long long ua = (a ^ a >> 63) - (a >> 63); + + /* Normalize. */ + cs = cntlzd(a); + ua <<= cs+1; + + /* Calculate the exponent, in 4 easy instructions. */ + css = 63-cs; + rx = 16383+css << 16 & ~css; + + /* Copy the sign bit from 'a'. */ + asm ("rlwimi %0,%1,0,0,0": "=r"(rx) : "r"(a >> 32), "0"(rx)); + + /* Put it all together. */ + result[3] = 0; + asm ("rlwimi %0,%1,16,16,31": "=r"(result[0]) : "r"(ua >> 32), "0"(rx)); + ua <<= 16; + result[2] = ua; + result[1] = ua >> 32; +} |