blob: 1c80e6a4f413ea9112bf8e754f89d04d10ae0670 (
plain) (
blame)
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
|
/*
Copyright 2022 Gabriel Jensen.
This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
If a copy of the MPL was not distributed with this file, You can obtain one at https://mozilla.org/MPL/2.0/.
*/
#include <zap/priv.h>
.globl zap_utf8enclen
zap_utf8enclen:
/*
zap_chr20 const * utf20
*/
#if defined(__amd64__)
# rdi: Address of the current character.
# rax: Length of the string.
# rsi: Current character.
movq $0x0,%rax
# Iterate over the input:
.loop:
movl (%rdi),%esi
# Test if we have reached the null-terminator:
testl %esi,%esi
jz .done
cmpl $0xFFFF,%esi
jg .oct4
cmpl $0x7FF,%esi
jg .oct3
cmpl $0x7F,%esi
jg .oct2
# One octet:
.oct1:
incq %rax
jmp .cnt
# Two octets:
.oct2:
addq $0x2,%rax
jmp .cnt
# Three octets:
.oct3:
addq $0x3,%rax
jmp .cnt
# Four octets:
.oct4:
addq $0x4,%rax
# Continue to the next codepoint:
.cnt:
addq $0x4,%rdi
jmp .loop
# Done:
.done:
ret
#endif
|
