sysdeps/alpha/soft-fp/ots_nintxq.c

   1 /* Software floating-point emulation: convert to fortran nearest.
   2    Copyright (C) 1997,1999,2004,2006 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Richard Henderson (rth@cygnus.com) and
   5                   Jakub Jelinek (jj@ultra.linux.cz).
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Lesser General Public
   9    License as published by the Free Software Foundation; either
  10    version 2.1 of the License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Lesser General Public License for more details.
  16
  17    You should have received a copy of the GNU Lesser General Public
  18    License along with the GNU C Library; if not, write to the Free
  19    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  20    02111-1307 USA.  */
  21
  22 #include "local-soft-fp.h"
  23
  24 long
  25 _OtsNintXQ (long al, long ah, long _round)
  26 {
  27   FP_DECL_EX;
  28   FP_DECL_Q(A); FP_DECL_Q(B); FP_DECL_Q(C);
  29   unsigned long r;
  30   long s;
  31
  32   /* If bit 3 is set, then integer overflow detection is requested.  */
  33   s = _round & 8 ? 1 : -1;
  34   _round = _round & 3;
  35
  36   FP_INIT_ROUNDMODE;
  37   FP_UNPACK_SEMIRAW_Q(A, a);
  38
  39   /* Build 0.5 * sign(A) */
  40   B_e = _FP_EXPBIAS_Q;
  41   __FP_FRAC_SET_2 (B, 0, 0);
  42   B_s = A_s;
  43
  44   FP_ADD_Q(C, A, B);
  45   _FP_FRAC_SRL_2(C, _FP_WORKBITS);
  46   _FP_FRAC_HIGH_RAW_Q(C) &= ~(_FP_W_TYPE)_FP_IMPLBIT_Q;
  47   FP_TO_INT_Q(r, C, 64, s);
  48   if (s > 0 && (_fex &= FP_EX_INVALID))
  49     FP_HANDLE_EXCEPTIONS;
  50
  51   return r;
  52 }