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  1. /*-------------------------------------------------------------------------
  2.    _fs2ulong.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. #ifdef FLOAT_ASM_MCS51
  35.  
  36. // unsigned long __fs2ulong (float x)
  37. static void dummy(void) __naked
  38. {
  39.         __asm
  40.         .globl  ___fs2ulong
  41. ___fs2ulong:
  42.         mov     r7, #158
  43.         .globl  fs2ulong_begin
  44. fs2ulong_begin:
  45.         lcall   fsgetarg
  46.         jnb     sign_a, fs2ulong_int
  47.         ljmp    fs_return_zero
  48.  
  49. fs2ulong_int:
  50.         clr     c
  51.         mov     a, r7
  52.         subb    a, exp_a
  53.         jnc     fs2ulong_int_ok
  54.         // if we get here, x >= 2^32
  55.         mov     a, #0xFF
  56.         mov     b, a
  57.         mov     dph, a
  58.         mov     dpl, a
  59.         ret
  60.  
  61. fs2ulong_int_ok:
  62.         mov     r1, #0
  63.         lcall   fs_rshift_a
  64.  
  65. fs2ulong_done:
  66.         mov     dpl, r1
  67.         mov     dph, r2
  68.         mov     b, r3
  69.         mov     a, r4
  70.         ret
  71.         __endasm;
  72. }
  73.  
  74. #else
  75.  
  76. /*
  77. ** libgcc support for software floating point.
  78. ** Copyright (C) 1991 by Pipeline Associates, Inc.  All rights reserved.
  79. ** Permission is granted to do *anything* you want with this file,
  80. ** commercial or otherwise, provided this message remains intact.  So there!
  81. ** I would appreciate receiving any updates/patches/changes that anyone
  82. ** makes, and am willing to be the repository for said changes (am I
  83. ** making a big mistake?).
  84. **
  85. ** Pat Wood
  86. ** Pipeline Associates, Inc.
  87. ** pipeline!phw@motown.com or
  88. ** sun!pipeline!phw or
  89. ** uunet!motown!pipeline!phw
  90. */
  91.  
  92. /* (c)2000/2001: hacked a little by johan.knol@iduna.nl for sdcc */
  93.  
  94.  
  95. union float_long
  96. {
  97.   float f;
  98.   long l;
  99. };
  100.  
  101. /* convert float to unsigned long */
  102. unsigned long
  103. __fs2ulong (float a1)
  104. {
  105.   volatile union float_long fl1;
  106.   volatile int exp;
  107.   volatile long l;
  108.  
  109.   fl1.f = a1;
  110.  
  111.   if (!fl1.l || SIGN(fl1.l))
  112.     return (0);
  113.  
  114.   exp = EXP (fl1.l) - EXCESS - 24;
  115.   l = MANT (fl1.l);
  116.  
  117.   l >>= -exp;
  118.  
  119.   return l;
  120. }
  121.  
  122. #endif
  123.