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glibc  2.9
s_scalblnl.c
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00001 /* Software floating-point emulation.
00002    scalblnl(x, exp)
00003    Copyright (C) 1999 Free Software Foundation, Inc.
00004    This file is part of the GNU C Library.
00005    Contributed by Jakub Jelinek (jj@ultra.linux.cz).
00006 
00007    The GNU C Library is free software; you can redistribute it and/or
00008    modify it under the terms of the GNU Lesser General Public
00009    License as published by the Free Software Foundation; either
00010    version 2.1 of the License, or (at your option) any later version.
00011 
00012    The GNU C Library is distributed in the hope that it will be useful,
00013    but WITHOUT ANY WARRANTY; without even the implied warranty of
00014    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015    Lesser General Public License for more details.
00016 
00017    You should have received a copy of the GNU Lesser General Public
00018    License along with the GNU C Library; if not, write to the Free
00019    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00020    02111-1307 USA.  */
00021 
00022 /*
00023  * scalblnl (long double x, long int n)
00024  * scalblnl(x,n) returns x* 2**n  computed by  exponent
00025  * manipulation rather than by actually performing an
00026  * exponentiation or a multiplication.
00027  */
00028 
00029 #include "soft-fp.h"
00030 #include "quad.h"
00031 
00032 long double __scalblnl(long double arg, int exp)
00033 {
00034   FP_DECL_EX;
00035   FP_DECL_Q(A);
00036   long double r;
00037 
00038   FP_UNPACK_Q(A, arg);
00039   switch (A_c)
00040     {
00041     case FP_CLS_ZERO:
00042       return arg;
00043     case FP_CLS_NAN:
00044     case FP_CLS_INF:
00045       FP_HANDLE_EXCEPTIONS;
00046       return arg;
00047     }
00048   A_e += exp;
00049   FP_PACK_Q(r, A);
00050   FP_HANDLE_EXCEPTIONS;
00051 
00052   return r;
00053 }
00054 
00055 weak_alias (__scalblnl, scalblnl)