1 # Alpha __mpn_add_n -- Add two limb vectors of the same length > 0 and
2 # store sum in a third limb vector.
3
4 # Copyright (C) 1995-2022 Free Software Foundation, Inc.
5
6 # This file is part of the GNU MP Library.
7
8 # The GNU MP Library is free software; you can redistribute it and/or modify
9 # it under the terms of the GNU Lesser General Public License as published by
10 # the Free Software Foundation; either version 2.1 of the License, or (at your
11 # option) any later version.
12
13 # The GNU MP Library is distributed in the hope that it will be useful, but
14 # WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15 # or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
16 # License for more details.
17
18 # You should have received a copy of the GNU Lesser General Public License
19 # along with the GNU MP Library.  If not, see <https://www.gnu.org/licenses/>.
20
21
22 # INPUT PARAMETERS
23 # res_ptr	$16
24 # s1_ptr	$17
25 # s2_ptr	$18
26 # size		$19
27
28	.set	noreorder
29	.set	noat
30.text
31	.align	3
32	.globl	__mpn_add_n
33	.ent	__mpn_add_n
34__mpn_add_n:
35	.frame	$30,0,$26,0
36
37	or	$31,$31,$25		# clear cy
38	subq	$19,4,$19		# decr loop cnt
39	blt	$19,.Lend2		# if less than 4 limbs, goto 2nd loop
40 # Start software pipeline for 1st loop
41	ldq	$0,0($18)
42	ldq	$1,8($18)
43	ldq	$4,0($17)
44	ldq	$5,8($17)
45	addq	$17,32,$17		# update s1_ptr
46	ldq	$2,16($18)
47	addq	$0,$4,$20		# 1st main add
48	ldq	$3,24($18)
49	subq	$19,4,$19		# decr loop cnt
50	ldq	$6,-16($17)
51	cmpult	$20,$0,$25		# compute cy from last add
52	ldq	$7,-8($17)
53	addq	$1,$25,$28		# cy add
54	addq	$18,32,$18		# update s2_ptr
55	addq	$5,$28,$21		# 2nd main add
56	cmpult	$28,$25,$8		# compute cy from last add
57	blt	$19,.Lend1		# if less than 4 limbs remain, jump
58 # 1st loop handles groups of 4 limbs in a software pipeline
59	.align	4
60.Loop:	cmpult	$21,$28,$25		# compute cy from last add
61	ldq	$0,0($18)
62	or	$8,$25,$25		# combine cy from the two adds
63	ldq	$1,8($18)
64	addq	$2,$25,$28		# cy add
65	ldq	$4,0($17)
66	addq	$28,$6,$22		# 3rd main add
67	ldq	$5,8($17)
68	cmpult	$28,$25,$8		# compute cy from last add
69	cmpult	$22,$28,$25		# compute cy from last add
70	stq	$20,0($16)
71	or	$8,$25,$25		# combine cy from the two adds
72	stq	$21,8($16)
73	addq	$3,$25,$28		# cy add
74	addq	$28,$7,$23		# 4th main add
75	cmpult	$28,$25,$8		# compute cy from last add
76	cmpult	$23,$28,$25		# compute cy from last add
77	addq	$17,32,$17		# update s1_ptr
78	or	$8,$25,$25		# combine cy from the two adds
79	addq	$16,32,$16		# update res_ptr
80	addq	$0,$25,$28		# cy add
81	ldq	$2,16($18)
82	addq	$4,$28,$20		# 1st main add
83	ldq	$3,24($18)
84	cmpult	$28,$25,$8		# compute cy from last add
85	ldq	$6,-16($17)
86	cmpult	$20,$28,$25		# compute cy from last add
87	ldq	$7,-8($17)
88	or	$8,$25,$25		# combine cy from the two adds
89	subq	$19,4,$19		# decr loop cnt
90	stq	$22,-16($16)
91	addq	$1,$25,$28		# cy add
92	stq	$23,-8($16)
93	addq	$5,$28,$21		# 2nd main add
94	addq	$18,32,$18		# update s2_ptr
95	cmpult	$28,$25,$8		# compute cy from last add
96	bge	$19,.Loop
97 # Finish software pipeline for 1st loop
98.Lend1:	cmpult	$21,$28,$25		# compute cy from last add
99	or	$8,$25,$25		# combine cy from the two adds
100	addq	$2,$25,$28		# cy add
101	addq	$28,$6,$22		# 3rd main add
102	cmpult	$28,$25,$8		# compute cy from last add
103	cmpult	$22,$28,$25		# compute cy from last add
104	stq	$20,0($16)
105	or	$8,$25,$25		# combine cy from the two adds
106	stq	$21,8($16)
107	addq	$3,$25,$28		# cy add
108	addq	$28,$7,$23		# 4th main add
109	cmpult	$28,$25,$8		# compute cy from last add
110	cmpult	$23,$28,$25		# compute cy from last add
111	or	$8,$25,$25		# combine cy from the two adds
112	addq	$16,32,$16		# update res_ptr
113	stq	$22,-16($16)
114	stq	$23,-8($16)
115.Lend2:	addq	$19,4,$19		# restore loop cnt
116	beq	$19,.Lret
117 # Start software pipeline for 2nd loop
118	ldq	$0,0($18)
119	ldq	$4,0($17)
120	subq	$19,1,$19
121	beq	$19,.Lend0
122 # 2nd loop handles remaining 1-3 limbs
123	.align	4
124.Loop0:	addq	$0,$25,$28		# cy add
125	ldq	$0,8($18)
126	addq	$4,$28,$20		# main add
127	ldq	$4,8($17)
128	addq	$18,8,$18
129	cmpult	$28,$25,$8		# compute cy from last add
130	addq	$17,8,$17
131	stq	$20,0($16)
132	cmpult	$20,$28,$25		# compute cy from last add
133	subq	$19,1,$19		# decr loop cnt
134	or	$8,$25,$25		# combine cy from the two adds
135	addq	$16,8,$16
136	bne	$19,.Loop0
137.Lend0:	addq	$0,$25,$28		# cy add
138	addq	$4,$28,$20		# main add
139	cmpult	$28,$25,$8		# compute cy from last add
140	cmpult	$20,$28,$25		# compute cy from last add
141	stq	$20,0($16)
142	or	$8,$25,$25		# combine cy from the two adds
143
144.Lret:	or	$25,$31,$0		# return cy
145	ret	$31,($26),1
146	.end	__mpn_add_n
147