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Diffstat (limited to 'sysdeps/powerpc/q_itoq.c')
-rw-r--r-- | sysdeps/powerpc/q_itoq.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/sysdeps/powerpc/q_itoq.c b/sysdeps/powerpc/q_itoq.c new file mode 100644 index 0000000000..aa737391bb --- /dev/null +++ b/sysdeps/powerpc/q_itoq.c @@ -0,0 +1,50 @@ +/* 32-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_itoq(int a); + Convert 'a' to long double. + */ + +void +__q_itoq(unsigned int result[4], int a) +{ + unsigned rx; + int cs, css; + + /* Note that if a==-2^31, then ua will be 2^31. */ + unsigned int ua = abs(a); + + /* Normalize. */ + cs = cntlzw(ua); + ua <<= cs+1; + + /* Calculate the exponent, in 4 easy instructions. */ + css = 31-cs; + rx = 16383+css << 16 & ~css; + + /* Copy the sign bit from 'a'. */ + asm ("rlwimi %0,%1,0,0,0": "=r"(rx) : "r"(a), "0"(rx)); + + /* Put it all together. */ + result[2] = result[3] = 0; + asm ("rlwimi %0,%1,16,16,31": "=r"(result[0]) : "r"(ua), "0"(rx)); + result[1] = ua << 16; +} |