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
|
dnl AMD64 mpn_divexact_by3 -- mpn division by 3, expecting no remainder.
dnl Copyright 2000, 2002, 2004, 2005 Free Software Foundation, Inc.
dnl
dnl This file is part of the GNU MP Library.
dnl
dnl The GNU MP Library is free software; you can redistribute it and/or
dnl modify it under the terms of the GNU Lesser General Public License as
dnl published by the Free Software Foundation; either version 3 of the
dnl License, or (at your option) any later version.
dnl
dnl The GNU MP Library is distributed in the hope that it will be useful,
dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
dnl Lesser General Public License for more details.
dnl
dnl You should have received a copy of the GNU Lesser General Public License
dnl along with the GNU MP Library. If not, see http://www.gnu.org/licenses/.
include(`../config.m4')
C cycles/limb
C K8: 5
C P4: 20.5
C P6-15: 8
C INPUT PARAMETERS
define(`rp', `%rdi')
define(`up', `%rsi')
define(`n', `%rdx')
define(`cy', `%rcx')
ASM_START()
PROLOGUE(mpn_divexact_by3c)
push %rbx
movq (up), %rax
movq $0x5555555555555555, %r10
leaq (%r10,%r10), %r11 C 0xAAAAAAAAAAAAAAAA
mov %rcx, %r8
imulq %r10, %r8
leaq 1(%r10,%r10), %r9 C 0xAAAAAAAAAAAAAAAB
leaq (up,n,8), up
leaq -8(rp,n,8), rp
negq n
imulq %r9, %rax
incq n
jz,pn .Lendo
.align 16
.Loop: movq (up,n,8), %rbx
imulq %r9, %rbx
addq %r8, %rax
cmpq %rcx, -8(up,n,8) C highly unlikely carry!!!
movq %rax, (rp,n,8)
jc,pn .Lc0
.Lb0: xor %r8, %r8
cmpq %rax, %r10
cmovc %r10, %r8
setc %cl
cmpq %rax, %r11
cmovc %r11, %r8
adcq $0, %rcx
incq n
jz,pn .Lende
movq (up,n,8), %rax
imulq %r9, %rax
addq %r8, %rbx
cmpq %rcx, -8(up,n,8)
movq %rbx, (rp,n,8)
jc,pn .Lc1
.Lb1: xor %r8, %r8
cmpq %rbx, %r10
cmovc %r10, %r8
setc %cl
cmpq %rbx, %r11
cmovc %r11, %r8
adcq $0, %rcx
incq n
jnz,pt .Loop
.Lendo: addq %r8, %rax
cmpq %rcx, -8(up,n,8)
movq %rax, (rp,n,8)
jc,pn .Lc2
.Lb2: xor %r8, %r8
cmpq %rax, %r10
cmovc %r10, %r8
setc %cl
cmpq %rax, %r11
cmovc %r11, %r8
adcq $0, %rcx
movq %rcx, %rax
pop %rbx
ret
.Lende: addq %r8, %rbx
cmpq %rcx, -8(up,n,8)
movq %rbx, (rp,n,8)
jc,pn .Lc3
.Lb3: xor %r8, %r8
cmpq %rbx, %r10
cmovc %r10, %r8
setc %cl
cmpq %rbx, %r11
cmovc %r11, %r8
adcq $0, %rcx
movq %rcx, %rax
pop %rbx
ret
.Lc0: incq %rax
jmp .Lb0
.Lc1: incq %rbx
jmp .Lb1
.Lc2: incq %rax
jmp .Lb2
.Lc3: incq %rbx
jmp .Lb3
EPILOGUE()
|
