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/*-------------------------------------------------------------------------
   _fslt.c - Floating point library in optimized assembly for 8051

   Copyright (c) 2004, Paul Stoffregen, paul@pjrc.com

   This library is free software; you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published by the
   Free Software Foundation; either version 2, or (at your option) any
   later version.

   This library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this library; see the file COPYING. If not, write to the
   Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
   MA 02110-1301, USA.

   As a special exception, if you link this library with other files,
   some of which are compiled with SDCC, to produce an executable,
   this library does not by itself cause the resulting executable to
   be covered by the GNU General Public License. This exception does
   not however invalidate any other reasons why the executable file
   might be covered by the GNU General Public License.
-------------------------------------------------------------------------*/


#define __SDCC_FLOAT_LIB
#include <float.h>


#ifdef FLOAT_ASM_MCS51

// char __fslt (float a, float b)
static void dummy(void) __naked
{
        __asm
        .globl  ___fslt
___fslt:
        mov     r7, a
        mov     r0, sp
        dec     r0
        dec     r0
        lcall   fs_check_negative_zeros
        setb    sign_a
        rlc     a
        mov     a, @r0
        jc      a_negative
a_positive:
        jnb     acc.7, ab_positive
        // a is positive and b is negative, so a > b
        mov     dpl, #0
        ret
a_negative:
        jb      acc.7, ab_negative
        // a is negative and b is positive, so a < b
        mov     dpl, #1
        ret
ab_positive:
        clr     sign_a
ab_negative:
        lcall   fs_compare_uint32
        mov     a, r1
        jnz     ab_different
        // a and b are equal
        mov     dpl, a
        ret
ab_different:
        jb      sign_a, skip_invert
        cpl     c
skip_invert:
        clr     a
        rlc     a
        mov     dpl, a
        ret
        __endasm;
}

#else

/*
** libgcc support for software floating point.
** Copyright (C) 1991 by Pipeline Associates, Inc.  All rights reserved.
** Permission is granted to do *anything* you want with this file,
** commercial or otherwise, provided this message remains intact.  So there!
** I would appreciate receiving any updates/patches/changes that anyone
** makes, and am willing to be the repository for said changes (am I
** making a big mistake?).
**
** Pat Wood
** Pipeline Associates, Inc.
** pipeline!phw@motown.com or
** sun!pipeline!phw or
** uunet!motown!pipeline!phw
*/

/* (c)2000/2001: hacked a little by johan.knol@iduna.nl for sdcc */

union float_long
  {
    float f;
    long l;
  };

/* compare two floats */
char __fslt (float a1, float a2)
{
  volatile union float_long fl1, fl2;

  fl1.f = a1;
  fl2.f = a2;

  if (((fl1.l | fl2.l) & 0x7FFFFFFF) == 0)
    return (0);

  if (fl1.l<0 && fl2.l<0) {
    if (fl2.l < fl1.l)
      return (1);
    return (0);
  }

  if (fl1.l < fl2.l)
    return (1);
  return (0);
}

#endif