xref: /netbsd-src/external/lgpl3/gmp/dist/mpn/alpha/add_n.asm (revision dd255ccea4286b0c44fa8fd48a9a19a768afe8e1)
1dnl  Alpha mpn_add_n -- Add two limb vectors of the same length > 0 and
2dnl  store sum in a third limb vector.
3
4dnl  Copyright 1995, 1999, 2000, 2005, 2011 Free Software Foundation, Inc.
5
6dnl  This file is part of the GNU MP Library.
7
8dnl  The GNU MP Library is free software; you can redistribute it and/or modify
9dnl  it under the terms of the GNU Lesser General Public License as published
10dnl  by the Free Software Foundation; either version 3 of the License, or (at
11dnl  your option) any later version.
12
13dnl  The GNU MP Library is distributed in the hope that it will be useful, but
14dnl  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15dnl  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
16dnl  License for more details.
17
18dnl  You should have received a copy of the GNU Lesser General Public License
19dnl  along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.
20
21include(`../config.m4')
22
23C      cycles/limb
24C EV4:     ?
25C EV5:     4.75
26C EV6:     3
27
28dnl  INPUT PARAMETERS
29dnl  res_ptr	r16
30dnl  s1_ptr	r17
31dnl  s2_ptr	r18
32dnl  size	r19
33
34ASM_START()
35PROLOGUE(mpn_add_nc)
36	bis	r20,r31,r25
37	br	L(com)
38EPILOGUE()
39PROLOGUE(mpn_add_n)
40	bis	r31,r31,r25		C clear cy
41L(com):	subq	r19,4,r19		C decr loop cnt
42	blt	r19,$Lend2		C if less than 4 limbs, goto 2nd loop
43C Start software pipeline for 1st loop
44	ldq	r0,0(r18)
45	ldq	r4,0(r17)
46	ldq	r1,8(r18)
47	ldq	r5,8(r17)
48	addq	r17,32,r17		C update s1_ptr
49	addq	r0,r4,r28		C 1st main add
50	ldq	r2,16(r18)
51	addq	r25,r28,r20		C 1st carry add
52	ldq	r3,24(r18)
53	cmpult	r28,r4,r8		C compute cy from last add
54	ldq	r6,-16(r17)
55	cmpult	r20,r28,r25		C compute cy from last add
56	ldq	r7,-8(r17)
57	bis	r8,r25,r25		C combine cy from the two adds
58	subq	r19,4,r19		C decr loop cnt
59	addq	r1,r5,r28		C 2nd main add
60	addq	r18,32,r18		C update s2_ptr
61	addq	r28,r25,r21		C 2nd carry add
62	cmpult	r28,r5,r8		C compute cy from last add
63	blt	r19,$Lend1		C if less than 4 limbs remain, jump
64C 1st loop handles groups of 4 limbs in a software pipeline
65	ALIGN(16)
66$Loop:	cmpult	r21,r28,r25		C compute cy from last add
67	ldq	r0,0(r18)
68	bis	r8,r25,r25		C combine cy from the two adds
69	ldq	r1,8(r18)
70	addq	r2,r6,r28		C 3rd main add
71	ldq	r4,0(r17)
72	addq	r28,r25,r22		C 3rd carry add
73	ldq	r5,8(r17)
74	cmpult	r28,r6,r8		C compute cy from last add
75	cmpult	r22,r28,r25		C compute cy from last add
76	stq	r20,0(r16)
77	bis	r8,r25,r25		C combine cy from the two adds
78	stq	r21,8(r16)
79	addq	r3,r7,r28		C 4th main add
80	addq	r28,r25,r23		C 4th carry add
81	cmpult	r28,r7,r8		C compute cy from last add
82	cmpult	r23,r28,r25		C compute cy from last add
83		addq	r17,32,r17		C update s1_ptr
84	bis	r8,r25,r25		C combine cy from the two adds
85		addq	r16,32,r16		C update res_ptr
86	addq	r0,r4,r28		C 1st main add
87	ldq	r2,16(r18)
88	addq	r25,r28,r20		C 1st carry add
89	ldq	r3,24(r18)
90	cmpult	r28,r4,r8		C compute cy from last add
91	ldq	r6,-16(r17)
92	cmpult	r20,r28,r25		C compute cy from last add
93	ldq	r7,-8(r17)
94	bis	r8,r25,r25		C combine cy from the two adds
95	subq	r19,4,r19		C decr loop cnt
96	stq	r22,-16(r16)
97	addq	r1,r5,r28		C 2nd main add
98	stq	r23,-8(r16)
99	addq	r25,r28,r21		C 2nd carry add
100		addq	r18,32,r18		C update s2_ptr
101	cmpult	r28,r5,r8		C compute cy from last add
102	bge	r19,$Loop
103C Finish software pipeline for 1st loop
104$Lend1:	cmpult	r21,r28,r25		C compute cy from last add
105	bis	r8,r25,r25		C combine cy from the two adds
106	addq	r2,r6,r28		C 3rd main add
107	addq	r28,r25,r22		C 3rd carry add
108	cmpult	r28,r6,r8		C compute cy from last add
109	cmpult	r22,r28,r25		C compute cy from last add
110	stq	r20,0(r16)
111	bis	r8,r25,r25		C combine cy from the two adds
112	stq	r21,8(r16)
113	addq	r3,r7,r28		C 4th main add
114	addq	r28,r25,r23		C 4th carry add
115	cmpult	r28,r7,r8		C compute cy from last add
116	cmpult	r23,r28,r25		C compute cy from last add
117	bis	r8,r25,r25		C combine cy from the two adds
118	addq	r16,32,r16		C update res_ptr
119	stq	r22,-16(r16)
120	stq	r23,-8(r16)
121$Lend2:	addq	r19,4,r19		C restore loop cnt
122	beq	r19,$Lret
123C Start software pipeline for 2nd loop
124	ldq	r0,0(r18)
125	ldq	r4,0(r17)
126	subq	r19,1,r19
127	beq	r19,$Lend0
128C 2nd loop handles remaining 1-3 limbs
129	ALIGN(16)
130$Loop0:	addq	r0,r4,r28		C main add
131	ldq	r0,8(r18)
132	cmpult	r28,r4,r8		C compute cy from last add
133	ldq	r4,8(r17)
134	addq	r28,r25,r20		C carry add
135	addq	r18,8,r18
136	addq	r17,8,r17
137	stq	r20,0(r16)
138	cmpult	r20,r28,r25		C compute cy from last add
139	subq	r19,1,r19		C decr loop cnt
140	bis	r8,r25,r25		C combine cy from the two adds
141	addq	r16,8,r16
142	bne	r19,$Loop0
143$Lend0:	addq	r0,r4,r28		C main add
144	addq	r28,r25,r20		C carry add
145	cmpult	r28,r4,r8		C compute cy from last add
146	cmpult	r20,r28,r25		C compute cy from last add
147	stq	r20,0(r16)
148	bis	r8,r25,r25		C combine cy from the two adds
149
150$Lret:	bis	r25,r31,r0		C return cy
151	ret	r31,(r26),1
152EPILOGUE()
153ASM_END()
154