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
|
/* Copyright (C) 2014-2021 Free Software Foundation, Inc.
Contributed by Dimitar Dimitrov <dimitar@dinux.eu>
This file 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 3, or (at your option) any
later version.
This file 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.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>.
(al + C * ah) * (bl + C * bh) = al * bl
+ C * ah * bl
+ C * al * bh
+ C * C * ah * bh -> discard, overflow
Where C=(1 << 32)
*/
#include "pru-asm.h"
.section .text.__pruabi_mpyll, "ax"
.global SYM(__pruabi_mpyll)
FUNC(__pruabi_mpyll)
SYM(__pruabi_mpyll):
/* + C * ah * bl */
mov r28, r15
mov r29, r16
nop
xin 0, r26, 8
/* + C * al * bh */
mov r28, r14
mov r29, r17
mov r15, r26 /* "Loose" ah, record only reslo. */
xin 0, r26, 8
/* + al * bl */
/* mov r28, r14 -> No need, already loaded. */
mov r29, r16
add r15, r15, r26
xin 0, r26, 8
mov r14, r26
add r15, r15, r27
ret
ENDFUNC(__pruabi_mpyll)
|
