sdcc/device/lib/_fs2uchar.c

   1 /*-------------------------------------------------------------------------
   2    _fs2uchar.c - Floating point library in optimized assembly for 8051
   3
   4    Copyright (c) 2004, Paul Stoffregen, paul@pjrc.com
   5
   6    This library is free software; you can redistribute it and/or modify it
   7    under the terms of the GNU General Public License as published by the
   8    Free Software Foundation; either version 2, or (at your option) any
   9    later version.
  10
  11    This library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this library; see the file COPYING. If not, write to the
  18    Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
  19    MA 02110-1301, USA.
  20
  21    As a special exception, if you link this library with other files,
  22    some of which are compiled with SDCC, to produce an executable,
  23    this library does not by itself cause the resulting executable to
  24    be covered by the GNU General Public License. This exception does
  25    not however invalidate any other reasons why the executable file
  26    might be covered by the GNU General Public License.
  27 -------------------------------------------------------------------------*/
  28
  29 #define __SDCC_FLOAT_LIB
  30 #include <float.h>
  31
  32
  33 #ifdef FLOAT_ASM_MCS51
  34
  35 // unsigned char __fs2uchar (float x)
  36 static void dummy(void) __naked
  37 {
  38         __asm
  39         .globl  ___fs2uchar
  40 ___fs2uchar:
  41         mov     r7, #134
  42         lcall   fs2ulong_begin
  43         mov     dpl, a
  44         ret
  45         __endasm;
  46 }
  47
  48 #else
  49
  50 /* convert float to unsigned char */
  51 unsigned char __fs2uchar (float f) __SDCC_FLOAT_NONBANKED
  52 {
  53   unsigned long ul=__fs2ulong(f);
  54   if (ul>=UCHAR_MAX) return UCHAR_MAX;
  55   return ul;
  56 }
  57
  58 #endif