xref: /netbsd-src/external/lgpl3/gmp/dist/mpn/powerpc64/mode64/mod_34lsub1.asm (revision cef8759bd76c1b621f8eab8faa6f208faabc2e15)
1dnl  PowerPC-64 mpn_mod_34lsub1 -- modulo 2^48-1.
2
3dnl  Copyright 2005 Free Software Foundation, Inc.
4
5dnl  This file is part of the GNU MP Library.
6dnl
7dnl  The GNU MP Library is free software; you can redistribute it and/or modify
8dnl  it under the terms of either:
9dnl
10dnl    * the GNU Lesser General Public License as published by the Free
11dnl      Software Foundation; either version 3 of the License, or (at your
12dnl      option) any later version.
13dnl
14dnl  or
15dnl
16dnl    * the GNU General Public License as published by the Free Software
17dnl      Foundation; either version 2 of the License, or (at your option) any
18dnl      later version.
19dnl
20dnl  or both in parallel, as here.
21dnl
22dnl  The GNU MP Library is distributed in the hope that it will be useful, but
23dnl  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
24dnl  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
25dnl  for more details.
26dnl
27dnl  You should have received copies of the GNU General Public License and the
28dnl  GNU Lesser General Public License along with the GNU MP Library.  If not,
29dnl  see https://www.gnu.org/licenses/.
30
31include(`../config.m4')
32
33C                   cycles/limb
34C POWER3/PPC630          1.33
35C POWER4/PPC970          1.5
36C POWER5                 1.32
37C POWER6                 2.35
38C POWER7                 1
39
40C INPUT PARAMETERS
41define(`up',`r3')
42define(`n',`r4')
43
44ASM_START()
45PROLOGUE(mpn_mod_34lsub1)
46	li	r8, 0
47	li	r9, 0
48	li	r10, 0
49	li	r11, 0
50
51	cmpdi	cr6, n, 3
52	blt	cr6, L(lt3)
53
54	li	r0, -0x5556		C 0xFFFFFFFFFFFFAAAA
55	rldimi	r0, r0, 16, 32		C 0xFFFFFFFFAAAAAAAA
56	rldimi	r0, r0, 32, 63		C 0xAAAAAAAAAAAAAAAB
57	mulhdu	r0, r0, n
58	srdi	r0, r0, 1		C r0 = [n / 3]
59	mtctr	r0
60
61	ld	r5, 0(up)
62	ld	r6, 8(up)
63	ld	r7, 16(up)
64	addi	up, up, 24
65	bdz	L(end)
66
67	ALIGN(16)
68L(top):	addc	r8, r8, r5
69	nop
70	ld	r5, 0(up)
71	adde	r9, r9, r6
72	ld	r6, 8(up)
73	adde	r10, r10, r7
74	ld	r7, 16(up)
75	addi	up, up, 48
76	addze	r11, r11
77	bdz	L(endx)
78	addc	r8, r8, r5
79	nop
80	ld	r5, -24(up)
81	adde	r9, r9, r6
82	ld	r6, -16(up)
83	adde	r10, r10, r7
84	ld	r7, -8(up)
85	addze	r11, r11
86	bdnz	L(top)
87
88	addi	up, up, 24
89L(endx):
90	addi	up, up, -24
91
92L(end):	addc	r8, r8, r5
93	adde	r9, r9, r6
94	adde	r10, r10, r7
95	addze	r11, r11
96
97	sldi	r5, r0, 1
98	add	r5, r5, r0		C r11 = n / 3 * 3
99	sub	n, n, r5		C n = n mod 3
100L(lt3):	cmpdi	cr6, n, 1
101	blt	cr6, L(2)
102
103	ld	r5, 0(up)
104	addc	r8, r8, r5
105	li	r6, 0
106	beq	cr6, L(1)
107
108	ld	r6, 8(up)
109L(1):	adde	r9, r9, r6
110	addze	r10, r10
111	addze	r11, r11
112
113L(2):	rldicl	r0, r8, 0, 16		C r0 = r8 mod 2^48
114	srdi	r3, r8, 48		C r3 = r8 div 2^48
115	rldic	r4, r9, 16, 16		C r4 = (r9 mod 2^32) << 16
116	srdi	r5, r9, 32		C r5 = r9 div 2^32
117	rldic	r6, r10, 32, 16		C r6 = (r10 mod 2^16) << 32
118	srdi	r7, r10, 16		C r7 = r10 div 2^16
119
120	add	r0, r0, r3
121	add	r4, r4, r5
122	add	r6, r6, r7
123
124	add	r0, r0, r4
125	add	r6, r6, r11
126
127	add	r3, r0, r6
128	blr
129EPILOGUE()
130
131C |__r10__|__r9___|__r8___|
132C |-----|-----|-----|-----|
133