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/* -*- Mode: Asm -*- */
/* Copyright (c) 2002 Michael Stumpf <mistumpf@de.pepperl-fuchs.com>
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in
the documentation and/or other materials provided with the
distribution.
* Neither the name of the copyright holders nor the names of
contributors may be used to endorse or promote products derived
from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
*/
/*
ldexp.S is part of FPlib V 0.3.0 ported to avr-as
for details see readme.fplib
*----------------------------------------------------------------------------------------
*
* A = 2^exp * x
* e.g.
* double y = ldexp( 3.45, 2 ) = 2^2 * 3.45 = 13.8
*/
#if !defined(DOXYGEN)
#include "gasava.inc"
#include "fplib.inc"
TEXT_SEG(fplib, ldexp)
FUNCTION(ldexp)
GLOBAL(ldexp)
BST rA3,7
RCALL _U(__fp_split1) ; clears rAE
TST rA3 ;
BREQ _ldexp_01 ; 2^x*0 = 0
CPI rPH,0xFF
BREQ _ldexp_10 ; negative
TST rPH
BREQ _ldexp_10
; overflow or underflow
_dlexp_00:
BRPL _ldexp_NaN ; overflow
_ldexp_01:
RJMP _U(__fp_zero)
_ldexp_NaN:
RJMP _U(__fp_nanERANGE) ; overflow
_ldexp_10:
ADD rA3,rPL
adc rT1c,rPH ;
; check for overflow
BRNE _ldexp_20
_ldexp_20:
RJMP _U(__fp_merge) ; rT0 must not be cleared : rAE=0 no rounding anyway
ENDFUNC
#endif /* not DOXYGEN */
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