Coverage Report

Created: 2025-07-11 06:24

/src/cpython/Objects/stringlib/find_max_char.h
Line
Count
Source
1
/* Finding the optimal width of unicode characters in a buffer */
2
3
/* find_max_char for one-byte will work for bytes objects as well. */
4
#if !STRINGLIB_IS_UNICODE && STRINGLIB_SIZEOF_CHAR > 1
5
# error "find_max_char.h is specific to Unicode"
6
#endif
7
8
/* Mask to quickly check whether a C 'size_t' contains a
9
   non-ASCII, UTF8-encoded char. */
10
#if (SIZEOF_SIZE_T == 8)
11
499M
# define UCS1_ASCII_CHAR_MASK 0x8080808080808080ULL
12
#elif (SIZEOF_SIZE_T == 4)
13
# define UCS1_ASCII_CHAR_MASK 0x80808080U
14
#else
15
# error C 'size_t' size should be either 4 or 8!
16
#endif
17
18
#if STRINGLIB_SIZEOF_CHAR == 1
19
20
Py_LOCAL_INLINE(Py_UCS4)
21
STRINGLIB(find_max_char)(const STRINGLIB_CHAR *begin, const STRINGLIB_CHAR *end)
22
42.5M
{
23
42.5M
    const unsigned char *p = (const unsigned char *) begin;
24
42.5M
    const unsigned char *_end = (const unsigned char *)end;
25
26
290M
    while (p < _end) {
27
264M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
39.0M
            const unsigned char *_p = p;
30
524M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
499M
                size_t value = *(const size_t *) _p;
32
499M
                if (value & UCS1_ASCII_CHAR_MASK)
33
13.9M
                    return 255;
34
485M
                _p += SIZEOF_SIZE_T;
35
485M
            }
36
25.0M
            p = _p;
37
25.0M
            if (p == _end)
38
511k
                break;
39
25.0M
        }
40
250M
        if (*p++ & 0x80)
41
2.75M
            return 255;
42
250M
    }
43
25.8M
    return 127;
44
42.5M
}
unicodeobject.c:ucs1lib_find_max_char
Line
Count
Source
22
42.5M
{
23
42.5M
    const unsigned char *p = (const unsigned char *) begin;
24
42.5M
    const unsigned char *_end = (const unsigned char *)end;
25
26
290M
    while (p < _end) {
27
264M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
39.0M
            const unsigned char *_p = p;
30
524M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
499M
                size_t value = *(const size_t *) _p;
32
499M
                if (value & UCS1_ASCII_CHAR_MASK)
33
13.9M
                    return 255;
34
485M
                _p += SIZEOF_SIZE_T;
35
485M
            }
36
25.0M
            p = _p;
37
25.0M
            if (p == _end)
38
511k
                break;
39
25.0M
        }
40
250M
        if (*p++ & 0x80)
41
2.75M
            return 255;
42
250M
    }
43
25.8M
    return 127;
44
42.5M
}
Unexecuted instantiation: unicodeobject.c:asciilib_find_max_char
Unexecuted instantiation: bytes_methods.c:stringlib_find_max_char
45
46
#undef ASCII_CHAR_MASK
47
48
#else /* STRINGLIB_SIZEOF_CHAR == 1 */
49
50
75.6M
#define MASK_ASCII 0xFFFFFF80
51
50.3M
#define MASK_UCS1 0xFFFFFF00
52
25.2M
#define MASK_UCS2 0xFFFF0000
53
54
47.9M
#define MAX_CHAR_ASCII 0x7f
55
22.3M
#define MAX_CHAR_UCS1  0xff
56
33.4M
#define MAX_CHAR_UCS2  0xffff
57
19.8M
#define MAX_CHAR_UCS4  0x10ffff
58
59
Py_LOCAL_INLINE(Py_UCS4)
60
STRINGLIB(find_max_char)(const STRINGLIB_CHAR *begin, const STRINGLIB_CHAR *end)
61
47.9M
{
62
#if STRINGLIB_SIZEOF_CHAR == 2
63
28.0M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
28.0M
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS2;
65
#elif STRINGLIB_SIZEOF_CHAR == 4
66
19.8M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
19.8M
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS4;
68
#else
69
#error Invalid STRINGLIB_SIZEOF_CHAR (must be 1, 2 or 4)
70
#endif
71
47.9M
    Py_UCS4 mask;
72
47.9M
    Py_ssize_t n = end - begin;
73
47.9M
    const STRINGLIB_CHAR *p = begin;
74
47.9M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
47.9M
    Py_UCS4 max_char;
76
77
47.9M
    max_char = MAX_CHAR_ASCII;
78
47.9M
    mask = MASK_ASCII;
79
2.30G
    while (p < unrolled_end) {
80
2.27G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
2.27G
        if (bits & mask) {
82
42.2M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
16.8M
                return max_char_limit;
85
16.8M
            }
86
25.4M
            if (mask == MASK_ASCII) {
87
20.7M
                max_char = MAX_CHAR_UCS1;
88
20.7M
                mask = MASK_UCS1;
89
20.7M
            }
90
4.65M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
4.65M
                assert(mask == MASK_UCS1);
93
4.65M
                max_char = MAX_CHAR_UCS2;
94
4.65M
                mask = MASK_UCS2;
95
4.65M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
25.4M
            continue;
98
42.2M
        }
99
2.22G
        p += 4;
100
2.22G
    }
101
97.1M
    while (p < end) {
102
66.8M
        if (p[0] & mask) {
103
3.07M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
813k
                return max_char_limit;
106
813k
            }
107
2.26M
            if (mask == MASK_ASCII) {
108
1.53M
                max_char = MAX_CHAR_UCS1;
109
1.53M
                mask = MASK_UCS1;
110
1.53M
            }
111
730k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
730k
                assert(mask == MASK_UCS1);
114
730k
                max_char = MAX_CHAR_UCS2;
115
730k
                mask = MASK_UCS2;
116
730k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
2.26M
            continue;
119
3.07M
        }
120
63.8M
        p++;
121
63.8M
    }
122
30.2M
    return max_char;
123
31.0M
}
unicodeobject.c:ucs4lib_find_max_char
Line
Count
Source
61
19.8M
{
62
#if STRINGLIB_SIZEOF_CHAR == 2
63
    const Py_UCS4 mask_limit = MASK_UCS1;
64
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS2;
65
#elif STRINGLIB_SIZEOF_CHAR == 4
66
19.8M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
19.8M
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS4;
68
#else
69
#error Invalid STRINGLIB_SIZEOF_CHAR (must be 1, 2 or 4)
70
#endif
71
19.8M
    Py_UCS4 mask;
72
19.8M
    Py_ssize_t n = end - begin;
73
19.8M
    const STRINGLIB_CHAR *p = begin;
74
19.8M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
19.8M
    Py_UCS4 max_char;
76
77
19.8M
    max_char = MAX_CHAR_ASCII;
78
19.8M
    mask = MASK_ASCII;
79
860M
    while (p < unrolled_end) {
80
842M
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
842M
        if (bits & mask) {
82
11.9M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
1.71M
                return max_char_limit;
85
1.71M
            }
86
10.2M
            if (mask == MASK_ASCII) {
87
5.58M
                max_char = MAX_CHAR_UCS1;
88
5.58M
                mask = MASK_UCS1;
89
5.58M
            }
90
4.65M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
4.65M
                assert(mask == MASK_UCS1);
93
4.65M
                max_char = MAX_CHAR_UCS2;
94
4.65M
                mask = MASK_UCS2;
95
4.65M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
10.2M
            continue;
98
11.9M
        }
99
830M
        p += 4;
100
830M
    }
101
56.9M
    while (p < end) {
102
38.9M
        if (p[0] & mask) {
103
1.64M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
105k
                return max_char_limit;
106
105k
            }
107
1.53M
            if (mask == MASK_ASCII) {
108
807k
                max_char = MAX_CHAR_UCS1;
109
807k
                mask = MASK_UCS1;
110
807k
            }
111
730k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
730k
                assert(mask == MASK_UCS1);
114
730k
                max_char = MAX_CHAR_UCS2;
115
730k
                mask = MASK_UCS2;
116
730k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
1.53M
            continue;
119
1.64M
        }
120
37.2M
        p++;
121
37.2M
    }
122
18.0M
    return max_char;
123
18.1M
}
unicodeobject.c:ucs2lib_find_max_char
Line
Count
Source
61
28.0M
{
62
28.0M
#if STRINGLIB_SIZEOF_CHAR == 2
63
28.0M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
28.0M
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS2;
65
#elif STRINGLIB_SIZEOF_CHAR == 4
66
    const Py_UCS4 mask_limit = MASK_UCS2;
67
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS4;
68
#else
69
#error Invalid STRINGLIB_SIZEOF_CHAR (must be 1, 2 or 4)
70
#endif
71
28.0M
    Py_UCS4 mask;
72
28.0M
    Py_ssize_t n = end - begin;
73
28.0M
    const STRINGLIB_CHAR *p = begin;
74
28.0M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
28.0M
    Py_UCS4 max_char;
76
77
28.0M
    max_char = MAX_CHAR_ASCII;
78
28.0M
    mask = MASK_ASCII;
79
1.44G
    while (p < unrolled_end) {
80
1.42G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
1.42G
        if (bits & mask) {
82
30.3M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
15.1M
                return max_char_limit;
85
15.1M
            }
86
15.1M
            if (mask == MASK_ASCII) {
87
15.1M
                max_char = MAX_CHAR_UCS1;
88
15.1M
                mask = MASK_UCS1;
89
15.1M
            }
90
0
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
0
                assert(mask == MASK_UCS1);
93
0
                max_char = MAX_CHAR_UCS2;
94
0
                mask = MASK_UCS2;
95
0
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
15.1M
            continue;
98
30.3M
        }
99
1.39G
        p += 4;
100
1.39G
    }
101
40.1M
    while (p < end) {
102
27.9M
        if (p[0] & mask) {
103
1.43M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
707k
                return max_char_limit;
106
707k
            }
107
728k
            if (mask == MASK_ASCII) {
108
728k
                max_char = MAX_CHAR_UCS1;
109
728k
                mask = MASK_UCS1;
110
728k
            }
111
0
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
0
                assert(mask == MASK_UCS1);
114
0
                max_char = MAX_CHAR_UCS2;
115
0
                mask = MASK_UCS2;
116
0
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
728k
            continue;
119
1.43M
        }
120
26.5M
        p++;
121
26.5M
    }
122
12.2M
    return max_char;
123
12.9M
}
124
125
#undef MASK_ASCII
126
#undef MASK_UCS1
127
#undef MASK_UCS2
128
#undef MAX_CHAR_ASCII
129
#undef MAX_CHAR_UCS1
130
#undef MAX_CHAR_UCS2
131
#undef MAX_CHAR_UCS4
132
133
#endif /* STRINGLIB_SIZEOF_CHAR == 1 */
134