195 lines
5.2 KiB
ArmAsm
195 lines
5.2 KiB
ArmAsm
.file "reg_u_mul.S"
|
|
/*
|
|
* reg_u_mul.S
|
|
*
|
|
* Core multiplication routine
|
|
*
|
|
*
|
|
* 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.
|
|
*
|
|
*
|
|
* $Id: reg_u_mul.s,v 1.7 1997/04/22 06:54:54 jdp Exp $
|
|
*
|
|
*/
|
|
|
|
/*---------------------------------------------------------------------------+
|
|
| Basic multiplication routine. |
|
|
| Does not check the resulting exponent for overflow/underflow |
|
|
| |
|
|
| reg_u_mul(FPU_REG *a, FPU_REG *b, FPU_REG *c, unsigned int cw); |
|
|
| |
|
|
| Internal working is at approx 128 bits. |
|
|
| Result is rounded to nearest 53 or 64 bits, using "nearest or even". |
|
|
+---------------------------------------------------------------------------*/
|
|
|
|
#include <gnu/i386/fpemul/fpu_asm.h>
|
|
|
|
|
|
.data
|
|
ALIGN_DATA
|
|
accum_0:
|
|
.long 0
|
|
accum_1:
|
|
.long 0
|
|
|
|
|
|
.text
|
|
ENTRY(reg_u_mul)
|
|
pushl %ebp
|
|
movl %esp,%ebp
|
|
pushl %esi
|
|
pushl %edi
|
|
pushl %ebx
|
|
|
|
movl PARAM1,%esi
|
|
movl PARAM2,%edi
|
|
|
|
#ifdef PARANOID
|
|
testl $0x80000000,SIGH(%esi)
|
|
jz L_bugged
|
|
testl $0x80000000,SIGH(%edi)
|
|
jz L_bugged
|
|
#endif PARANOID
|
|
|
|
#ifdef DENORM_OPERAND
|
|
movl EXP(%esi),%eax
|
|
cmpl EXP_UNDER,%eax
|
|
jg xOp1_not_denorm
|
|
|
|
call _denormal_operand
|
|
orl %eax,%eax
|
|
jnz FPU_Arith_exit
|
|
|
|
xOp1_not_denorm:
|
|
movl EXP(%edi),%eax
|
|
cmpl EXP_UNDER,%eax
|
|
jg xOp2_not_denorm
|
|
|
|
call _denormal_operand
|
|
orl %eax,%eax
|
|
jnz FPU_Arith_exit
|
|
|
|
xOp2_not_denorm:
|
|
#endif DENORM_OPERAND
|
|
|
|
xorl %ecx,%ecx
|
|
xorl %ebx,%ebx
|
|
|
|
movl SIGL(%esi),%eax
|
|
mull SIGL(%edi)
|
|
movl %eax,accum_0
|
|
movl %edx,accum_1
|
|
|
|
movl SIGL(%esi),%eax
|
|
mull SIGH(%edi)
|
|
addl %eax,accum_1
|
|
adcl %edx,%ebx
|
|
/* adcl $0,%ecx *//* overflow here is not possible */
|
|
|
|
movl SIGH(%esi),%eax
|
|
mull SIGL(%edi)
|
|
addl %eax,accum_1
|
|
adcl %edx,%ebx
|
|
adcl $0,%ecx
|
|
|
|
movl SIGH(%esi),%eax
|
|
mull SIGH(%edi)
|
|
addl %eax,%ebx
|
|
adcl %edx,%ecx
|
|
|
|
movl EXP(%esi),%eax /* Compute the exponent */
|
|
addl EXP(%edi),%eax
|
|
subl EXP_BIAS-1,%eax
|
|
/* Have now finished with the sources */
|
|
movl PARAM3,%edi /* Point to the destination */
|
|
movl %eax,EXP(%edi)
|
|
|
|
/* Now make sure that the result is normalized */
|
|
testl $0x80000000,%ecx
|
|
jnz LResult_Normalised
|
|
|
|
/* Normalize by shifting left one bit */
|
|
shll $1,accum_0
|
|
rcll $1,accum_1
|
|
rcll $1,%ebx
|
|
rcll $1,%ecx
|
|
decl EXP(%edi)
|
|
|
|
LResult_Normalised:
|
|
movl accum_0,%eax
|
|
movl accum_1,%edx
|
|
orl %eax,%eax
|
|
jz L_extent_zero
|
|
|
|
orl $1,%edx
|
|
|
|
L_extent_zero:
|
|
movl %ecx,%eax
|
|
jmp FPU_round
|
|
|
|
|
|
#ifdef PARANOID
|
|
L_bugged:
|
|
pushl EX_INTERNAL|0x205
|
|
call EXCEPTION
|
|
pop %ebx
|
|
jmp L_exit
|
|
|
|
L_exit:
|
|
popl %ebx
|
|
popl %edi
|
|
popl %esi
|
|
leave
|
|
ret
|
|
#endif PARANOID
|
|
|