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
|
# Alpha __mpn_add_n -- Add two limb vectors of the same length > 0 and
# store sum in a third limb vector.
# Copyright (C) 1995-2021 Free Software Foundation, Inc.
# This file is part of the GNU MP Library.
# The GNU MP Library is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or (at your
# option) any later version.
# The GNU MP Library 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 Lesser General Public
# License for more details.
# You should have received a copy of the GNU Lesser General Public License
# along with the GNU MP Library. If not, see <https://www.gnu.org/licenses/>.
# INPUT PARAMETERS
# res_ptr $16
# s1_ptr $17
# s2_ptr $18
# size $19
.set noreorder
.set noat
.text
.align 3
.globl __mpn_add_n
.ent __mpn_add_n
__mpn_add_n:
.frame $30,0,$26,0
or $31,$31,$25 # clear cy
subq $19,4,$19 # decr loop cnt
blt $19,.Lend2 # if less than 4 limbs, goto 2nd loop
# Start software pipeline for 1st loop
ldq $0,0($18)
ldq $1,8($18)
ldq $4,0($17)
ldq $5,8($17)
addq $17,32,$17 # update s1_ptr
ldq $2,16($18)
addq $0,$4,$20 # 1st main add
ldq $3,24($18)
subq $19,4,$19 # decr loop cnt
ldq $6,-16($17)
cmpult $20,$0,$25 # compute cy from last add
ldq $7,-8($17)
addq $1,$25,$28 # cy add
addq $18,32,$18 # update s2_ptr
addq $5,$28,$21 # 2nd main add
cmpult $28,$25,$8 # compute cy from last add
blt $19,.Lend1 # if less than 4 limbs remain, jump
# 1st loop handles groups of 4 limbs in a software pipeline
.align 4
.Loop: cmpult $21,$28,$25 # compute cy from last add
ldq $0,0($18)
or $8,$25,$25 # combine cy from the two adds
ldq $1,8($18)
addq $2,$25,$28 # cy add
ldq $4,0($17)
addq $28,$6,$22 # 3rd main add
ldq $5,8($17)
cmpult $28,$25,$8 # compute cy from last add
cmpult $22,$28,$25 # compute cy from last add
stq $20,0($16)
or $8,$25,$25 # combine cy from the two adds
stq $21,8($16)
addq $3,$25,$28 # cy add
addq $28,$7,$23 # 4th main add
cmpult $28,$25,$8 # compute cy from last add
cmpult $23,$28,$25 # compute cy from last add
addq $17,32,$17 # update s1_ptr
or $8,$25,$25 # combine cy from the two adds
addq $16,32,$16 # update res_ptr
addq $0,$25,$28 # cy add
ldq $2,16($18)
addq $4,$28,$20 # 1st main add
ldq $3,24($18)
cmpult $28,$25,$8 # compute cy from last add
ldq $6,-16($17)
cmpult $20,$28,$25 # compute cy from last add
ldq $7,-8($17)
or $8,$25,$25 # combine cy from the two adds
subq $19,4,$19 # decr loop cnt
stq $22,-16($16)
addq $1,$25,$28 # cy add
stq $23,-8($16)
addq $5,$28,$21 # 2nd main add
addq $18,32,$18 # update s2_ptr
cmpult $28,$25,$8 # compute cy from last add
bge $19,.Loop
# Finish software pipeline for 1st loop
.Lend1: cmpult $21,$28,$25 # compute cy from last add
or $8,$25,$25 # combine cy from the two adds
addq $2,$25,$28 # cy add
addq $28,$6,$22 # 3rd main add
cmpult $28,$25,$8 # compute cy from last add
cmpult $22,$28,$25 # compute cy from last add
stq $20,0($16)
or $8,$25,$25 # combine cy from the two adds
stq $21,8($16)
addq $3,$25,$28 # cy add
addq $28,$7,$23 # 4th main add
cmpult $28,$25,$8 # compute cy from last add
cmpult $23,$28,$25 # compute cy from last add
or $8,$25,$25 # combine cy from the two adds
addq $16,32,$16 # update res_ptr
stq $22,-16($16)
stq $23,-8($16)
.Lend2: addq $19,4,$19 # restore loop cnt
beq $19,.Lret
# Start software pipeline for 2nd loop
ldq $0,0($18)
ldq $4,0($17)
subq $19,1,$19
beq $19,.Lend0
# 2nd loop handles remaining 1-3 limbs
.align 4
.Loop0: addq $0,$25,$28 # cy add
ldq $0,8($18)
addq $4,$28,$20 # main add
ldq $4,8($17)
addq $18,8,$18
cmpult $28,$25,$8 # compute cy from last add
addq $17,8,$17
stq $20,0($16)
cmpult $20,$28,$25 # compute cy from last add
subq $19,1,$19 # decr loop cnt
or $8,$25,$25 # combine cy from the two adds
addq $16,8,$16
bne $19,.Loop0
.Lend0: addq $0,$25,$28 # cy add
addq $4,$28,$20 # main add
cmpult $28,$25,$8 # compute cy from last add
cmpult $20,$28,$25 # compute cy from last add
stq $20,0($16)
or $8,$25,$25 # combine cy from the two adds
.Lret: or $25,$31,$0 # return cy
ret $31,($26),1
.end __mpn_add_n
|