1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
|
.file "reg_u_mul.S"
/* $OpenBSD: reg_u_mul.s,v 1.2 2002/10/12 07:12:59 pvalchev Exp $ */
/*
* 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.
*
*
* $FreeBSD: reg_u_mul.s,v 1.3 1994/06/10 07:44:58 rich 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 <machine/asm.h>
#include <gnu/arch/i386/fpemul/exception.h>
#include <gnu/arch/i386/fpemul/fpu_asm.h>
#include <gnu/arch/i386/fpemul/control_w.h>
.data
#ifdef __ELF__
.align 4,0
#else
.align 2,0
#endif
accum_0:
.long 0
accum_1:
.long 0
.text
#ifdef __ELF__
.align 4,144
#else
.align 2,144
#endif
.globl _C_LABEL(reg_u_mul)
_C_LABEL(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 _C_LABEL(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 _C_LABEL(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
|
