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
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
|
//go:build !appengine && gc && !purego
// +build !appengine
// +build gc
// +build !purego
#include "textflag.h"
// Registers:
#define h AX
#define d AX
#define p SI // pointer to advance through b
#define n DX
#define end BX // loop end
#define v1 R8
#define v2 R9
#define v3 R10
#define v4 R11
#define x R12
#define prime1 R13
#define prime2 R14
#define prime4 DI
#define round(acc, x) \
IMULQ prime2, x \
ADDQ x, acc \
ROLQ $31, acc \
IMULQ prime1, acc
// round0 performs the operation x = round(0, x).
#define round0(x) \
IMULQ prime2, x \
ROLQ $31, x \
IMULQ prime1, x
// mergeRound applies a merge round on the two registers acc and x.
// It assumes that prime1, prime2, and prime4 have been loaded.
#define mergeRound(acc, x) \
round0(x) \
XORQ x, acc \
IMULQ prime1, acc \
ADDQ prime4, acc
// blockLoop processes as many 32-byte blocks as possible,
// updating v1, v2, v3, and v4. It assumes that there is at least one block
// to process.
#define blockLoop() \
loop: \
MOVQ +0(p), x \
round(v1, x) \
MOVQ +8(p), x \
round(v2, x) \
MOVQ +16(p), x \
round(v3, x) \
MOVQ +24(p), x \
round(v4, x) \
ADDQ $32, p \
CMPQ p, end \
JLE loop
// func Sum64(b []byte) uint64
TEXT ·Sum64(SB), NOSPLIT|NOFRAME, $0-32
// Load fixed primes.
MOVQ ·primes+0(SB), prime1
MOVQ ·primes+8(SB), prime2
MOVQ ·primes+24(SB), prime4
// Load slice.
MOVQ b_base+0(FP), p
MOVQ b_len+8(FP), n
LEAQ (p)(n*1), end
// The first loop limit will be len(b)-32.
SUBQ $32, end
// Check whether we have at least one block.
CMPQ n, $32
JLT noBlocks
// Set up initial state (v1, v2, v3, v4).
MOVQ prime1, v1
ADDQ prime2, v1
MOVQ prime2, v2
XORQ v3, v3
XORQ v4, v4
SUBQ prime1, v4
blockLoop()
MOVQ v1, h
ROLQ $1, h
MOVQ v2, x
ROLQ $7, x
ADDQ x, h
MOVQ v3, x
ROLQ $12, x
ADDQ x, h
MOVQ v4, x
ROLQ $18, x
ADDQ x, h
mergeRound(h, v1)
mergeRound(h, v2)
mergeRound(h, v3)
mergeRound(h, v4)
JMP afterBlocks
noBlocks:
MOVQ ·primes+32(SB), h
afterBlocks:
ADDQ n, h
ADDQ $24, end
CMPQ p, end
JG try4
loop8:
MOVQ (p), x
ADDQ $8, p
round0(x)
XORQ x, h
ROLQ $27, h
IMULQ prime1, h
ADDQ prime4, h
CMPQ p, end
JLE loop8
try4:
ADDQ $4, end
CMPQ p, end
JG try1
MOVL (p), x
ADDQ $4, p
IMULQ prime1, x
XORQ x, h
ROLQ $23, h
IMULQ prime2, h
ADDQ ·primes+16(SB), h
try1:
ADDQ $4, end
CMPQ p, end
JGE finalize
loop1:
MOVBQZX (p), x
ADDQ $1, p
IMULQ ·primes+32(SB), x
XORQ x, h
ROLQ $11, h
IMULQ prime1, h
CMPQ p, end
JL loop1
finalize:
MOVQ h, x
SHRQ $33, x
XORQ x, h
IMULQ prime2, h
MOVQ h, x
SHRQ $29, x
XORQ x, h
IMULQ ·primes+16(SB), h
MOVQ h, x
SHRQ $32, x
XORQ x, h
MOVQ h, ret+24(FP)
RET
// func writeBlocks(d *Digest, b []byte) int
TEXT ·writeBlocks(SB), NOSPLIT|NOFRAME, $0-40
// Load fixed primes needed for round.
MOVQ ·primes+0(SB), prime1
MOVQ ·primes+8(SB), prime2
// Load slice.
MOVQ b_base+8(FP), p
MOVQ b_len+16(FP), n
LEAQ (p)(n*1), end
SUBQ $32, end
// Load vN from d.
MOVQ s+0(FP), d
MOVQ 0(d), v1
MOVQ 8(d), v2
MOVQ 16(d), v3
MOVQ 24(d), v4
// We don't need to check the loop condition here; this function is
// always called with at least one block of data to process.
blockLoop()
// Copy vN back to d.
MOVQ v1, 0(d)
MOVQ v2, 8(d)
MOVQ v3, 16(d)
MOVQ v4, 24(d)
// The number of bytes written is p minus the old base pointer.
SUBQ b_base+8(FP), p
MOVQ p, ret+32(FP)
RET
|
