Subversion Repositories NedoOS

Rev

Blame | Last modification | View Log | Download

  1. /*-------------------------------------------------------------------------
  2.    _fs2schar.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.  
  30. #define __SDCC_FLOAT_LIB
  31. #include <float.h>
  32.  
  33.  
  34.  
  35. #ifdef FLOAT_ASM_MCS51
  36.  
  37. // char __fs2schar (float x)
  38. static void dummy(void) __naked
  39. {
  40.         __asm
  41.         .globl  ___fs2schar
  42. ___fs2schar:
  43.         lcall   ___fs2slong
  44.         jnz     fs2schar_not_zero
  45.         mov     a, dpl
  46.         orl     a, dph
  47.         orl     a, b
  48.         jnz     fs2schar_clr_a
  49.         ret
  50. fs2schar_clr_a:
  51.         clr a
  52. fs2schar_not_zero:
  53.         jnb     sign_a, fs2schar_pos
  54. fs2schar_neg:
  55.         cpl     a
  56.         jnz     fs2schar_maxval_neg
  57.         mov     a, b
  58.         cpl     a
  59.         jnz     fs2schar_maxval_neg
  60.         mov     a, dph
  61.         cpl     a
  62.         jnz     fs2schar_maxval_neg
  63.         mov     a, dpl
  64.         jnb     acc.7, fs2schar_maxval_neg
  65.         ret
  66. fs2schar_maxval_neg:
  67.         mov     dpl, #0x80
  68.         ret
  69. fs2schar_pos:
  70.         jnz     fs2schar_maxval_pos
  71.         mov     a, b
  72.         jnz     fs2schar_maxval_pos
  73.         mov     a, dph
  74.         jnz     fs2schar_maxval_pos
  75.         mov     a, dpl
  76.         jb      acc.7, fs2schar_maxval_pos
  77.         ret
  78. fs2schar_maxval_pos:
  79.         mov     dpl, #0x7F
  80.         ret
  81.         __endasm;
  82. }
  83.  
  84. #else
  85.  
  86. /* convert float to signed char */
  87. signed char __fs2schar (float f)
  88. {
  89.   signed long sl=__fs2slong(f);
  90.   if (sl>=SCHAR_MAX)
  91.     return SCHAR_MAX;
  92.   if (sl<=SCHAR_MIN)
  93.     return -SCHAR_MIN;
  94.   return sl;
  95. }
  96.  
  97. #endif
  98.