freebsd-dev/sys/gnu/i386/fpemul/polynomial.s
2002-05-13 12:55:30 +00:00

191 lines
4.8 KiB
ArmAsm

/*
* polynomial.S
*
* Fixed point arithmetic polynomial evaluation.
*
* Call from C as:
* void polynomial(unsigned accum[], unsigned x[], unsigned terms[][2],
* int n)
*
* Computes:
* terms[0] + (terms[1] + (terms[2] + ... + (terms[n-1]*x)*x)*x)*x) ... )*x
* The result is returned in accum.
*
*
* Copyright (C) 1992,1993,1994
* W. Metzenthen, 22 Parker St, Ormond, Vic 3163,
* Australia. E-mail billm@vaxc.cc.monash.edu.au
* All rights reserved.
*
* This copyright notice covers the redistribution and use of the
* FPU emulator developed by W. Metzenthen. It covers only its use
* in the 386BSD, FreeBSD and NetBSD operating systems. Any other
* use is not permitted under this copyright.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must include information specifying
* that source code for the emulator is freely available and include
* either:
* a) an offer to provide the source code for a nominal distribution
* fee, or
* b) list at least two alternative methods whereby the source
* can be obtained, e.g. a publically accessible bulletin board
* and an anonymous ftp site from which the software can be
* downloaded.
* 3. All advertising materials specifically mentioning features or use of
* this emulator must acknowledge that it was developed by W. Metzenthen.
* 4. The name of W. Metzenthen may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED ``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
* W. METZENTHEN 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.
*
*
* The purpose of this copyright, based upon the Berkeley copyright, is to
* ensure that the covered software remains freely available to everyone.
*
* The software (with necessary differences) is also available, but under
* the terms of the GNU copyleft, for the Linux operating system and for
* the djgpp ms-dos extender.
*
* W. Metzenthen June 1994.
*
*
* $FreeBSD$
*
*/
.file "fpolynom.s"
#include <gnu/i386/fpemul/fpu_asm.h>
/* #define EXTRA_PRECISE*/
#define TERM_SIZE $8
.text
ENTRY(polynomial)
pushl %ebp
movl %esp,%ebp
subl $32,%esp
pushl %esi
pushl %edi
pushl %ebx
movl PARAM1,%esi /* accum */
movl PARAM2,%edi /* x */
movl PARAM3,%ebx /* terms */
movl PARAM4,%ecx /* n */
movl TERM_SIZE,%eax
mull %ecx
movl %eax,%ecx
movl 4(%ebx,%ecx,1),%edx /* terms[n] */
movl %edx,-20(%ebp)
movl (%ebx,%ecx,1),%edx /* terms[n] */
movl %edx,-24(%ebp)
xor %eax,%eax
movl %eax,-28(%ebp)
subl TERM_SIZE,%ecx
js L_accum_done
L_accum_loop:
xor %eax,%eax
movl %eax,-4(%ebp)
movl %eax,-8(%ebp)
#ifdef EXTRA_PRECISE
movl -28(%ebp),%eax
mull 4(%edi) /* x ms long */
movl %edx,-12(%ebp)
#endif /* EXTRA_PRECISE */
movl -24(%ebp),%eax
mull (%edi) /* x ls long */
/* movl %eax,-16(%ebp) */ /* Not needed */
addl %edx,-12(%ebp)
adcl $0,-8(%ebp)
movl -24(%ebp),%eax
mull 4(%edi) /* x ms long */
addl %eax,-12(%ebp)
adcl %edx,-8(%ebp)
adcl $0,-4(%ebp)
movl -20(%ebp),%eax
mull (%edi)
addl %eax,-12(%ebp)
adcl %edx,-8(%ebp)
adcl $0,-4(%ebp)
movl -20(%ebp),%eax
mull 4(%edi)
addl %eax,-8(%ebp)
adcl %edx,-4(%ebp)
/* Now add the next term */
movl (%ebx,%ecx,1),%eax
addl %eax,-8(%ebp)
movl 4(%ebx,%ecx,1),%eax
adcl %eax,-4(%ebp)
/* And put into the second register */
movl -4(%ebp),%eax
movl %eax,-20(%ebp)
movl -8(%ebp),%eax
movl %eax,-24(%ebp)
#ifdef EXTRA_PRECISE
movl -12(%ebp),%eax
movl %eax,-28(%ebp)
#else
testb $128,-25(%ebp)
je L_no_poly_round
addl $1,-24(%ebp)
adcl $0,-20(%ebp)
L_no_poly_round:
#endif /* EXTRA_PRECISE */
subl TERM_SIZE,%ecx
jns L_accum_loop
L_accum_done:
#ifdef EXTRA_PRECISE
/* And round the result */
testb $128,-25(%ebp)
je L_poly_done
addl $1,-24(%ebp)
adcl $0,-20(%ebp)
#endif /* EXTRA_PRECISE */
L_poly_done:
movl -24(%ebp),%eax
movl %eax,(%esi)
movl -20(%ebp),%eax
movl %eax,4(%esi)
popl %ebx
popl %edi
popl %esi
leave
ret