Coverage Report

Created: 2026-05-16 06:46

next uncovered line (L), next uncovered region (R), next uncovered branch (B)
/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
452M
# 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
41.2M
{
23
41.2M
    const unsigned char *p = (const unsigned char *) begin;
24
41.2M
    const unsigned char *_end = (const unsigned char *)end;
25
26
260M
    while (p < _end) {
27
229M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
34.3M
            const unsigned char *_p = p;
30
481M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
452M
                size_t value = *(const size_t *) _p;
32
452M
                if (value & UCS1_ASCII_CHAR_MASK)
33
5.87M
                    return 255;
34
446M
                _p += SIZEOF_SIZE_T;
35
446M
            }
36
28.4M
            p = _p;
37
28.4M
            if (p == _end)
38
726k
                break;
39
28.4M
        }
40
222M
        if (*p++ & 0x80)
41
3.66M
            return 255;
42
222M
    }
43
31.7M
    return 127;
44
41.2M
}
Unexecuted instantiation: unicode_writer.c:ucs1lib_find_max_char
unicodeobject.c:ucs1lib_find_max_char
Line
Count
Source
22
41.2M
{
23
41.2M
    const unsigned char *p = (const unsigned char *) begin;
24
41.2M
    const unsigned char *_end = (const unsigned char *)end;
25
26
260M
    while (p < _end) {
27
229M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
34.3M
            const unsigned char *_p = p;
30
481M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
452M
                size_t value = *(const size_t *) _p;
32
452M
                if (value & UCS1_ASCII_CHAR_MASK)
33
5.87M
                    return 255;
34
446M
                _p += SIZEOF_SIZE_T;
35
446M
            }
36
28.4M
            p = _p;
37
28.4M
            if (p == _end)
38
726k
                break;
39
28.4M
        }
40
222M
        if (*p++ & 0x80)
41
3.66M
            return 255;
42
222M
    }
43
31.7M
    return 127;
44
41.2M
}
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
75.7M
#define MASK_ASCII 0xFFFFFF80
51
50.5M
#define MASK_UCS1 0xFFFFFF00
52
25.1M
#define MASK_UCS2 0xFFFF0000
53
54
46.1M
#define MAX_CHAR_ASCII 0x7f
55
23.7M
#define MAX_CHAR_UCS1  0xff
56
32.5M
#define MAX_CHAR_UCS2  0xffff
57
19.3M
#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
46.1M
{
62
#if STRINGLIB_SIZEOF_CHAR == 2
63
26.8M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
26.8M
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS2;
65
#elif STRINGLIB_SIZEOF_CHAR == 4
66
19.3M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
19.3M
    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
46.1M
    Py_UCS4 mask;
72
46.1M
    Py_ssize_t n = end - begin;
73
46.1M
    const STRINGLIB_CHAR *p = begin;
74
46.1M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
46.1M
    Py_UCS4 max_char;
76
77
46.1M
    max_char = MAX_CHAR_ASCII;
78
46.1M
    mask = MASK_ASCII;
79
1.57G
    while (p < unrolled_end) {
80
1.54G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
1.54G
        if (bits & mask) {
82
43.3M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
16.9M
                return max_char_limit;
85
16.9M
            }
86
26.4M
            if (mask == MASK_ASCII) {
87
21.5M
                max_char = MAX_CHAR_UCS1;
88
21.5M
                mask = MASK_UCS1;
89
21.5M
            }
90
4.87M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
4.87M
                assert(mask == MASK_UCS1);
93
4.87M
                max_char = MAX_CHAR_UCS2;
94
4.87M
                mask = MASK_UCS2;
95
4.87M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
26.4M
            continue;
98
43.3M
        }
99
1.49G
        p += 4;
100
1.49G
    }
101
82.8M
    while (p < end) {
102
54.8M
        if (p[0] & mask) {
103
4.38M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
1.28M
                return max_char_limit;
106
1.28M
            }
107
3.10M
            if (mask == MASK_ASCII) {
108
2.19M
                max_char = MAX_CHAR_UCS1;
109
2.19M
                mask = MASK_UCS1;
110
2.19M
            }
111
909k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
909k
                assert(mask == MASK_UCS1);
114
909k
                max_char = MAX_CHAR_UCS2;
115
909k
                mask = MASK_UCS2;
116
909k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
3.10M
            continue;
119
4.38M
        }
120
50.4M
        p++;
121
50.4M
    }
122
27.9M
    return max_char;
123
29.2M
}
unicodeobject.c:ucs4lib_find_max_char
Line
Count
Source
61
19.3M
{
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
19.3M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
19.3M
    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
19.3M
    Py_UCS4 mask;
72
19.3M
    Py_ssize_t n = end - begin;
73
19.3M
    const STRINGLIB_CHAR *p = begin;
74
19.3M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
19.3M
    Py_UCS4 max_char;
76
77
19.3M
    max_char = MAX_CHAR_ASCII;
78
19.3M
    mask = MASK_ASCII;
79
495M
    while (p < unrolled_end) {
80
477M
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
477M
        if (bits & mask) {
82
11.9M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
1.26M
                return max_char_limit;
85
1.26M
            }
86
10.6M
            if (mask == MASK_ASCII) {
87
5.76M
                max_char = MAX_CHAR_UCS1;
88
5.76M
                mask = MASK_UCS1;
89
5.76M
            }
90
4.87M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
4.87M
                assert(mask == MASK_UCS1);
93
4.87M
                max_char = MAX_CHAR_UCS2;
94
4.87M
                mask = MASK_UCS2;
95
4.87M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
10.6M
            continue;
98
11.9M
        }
99
465M
        p += 4;
100
465M
    }
101
51.7M
    while (p < end) {
102
33.7M
        if (p[0] & mask) {
103
2.01M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
124k
                return max_char_limit;
106
124k
            }
107
1.88M
            if (mask == MASK_ASCII) {
108
976k
                max_char = MAX_CHAR_UCS1;
109
976k
                mask = MASK_UCS1;
110
976k
            }
111
909k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
909k
                assert(mask == MASK_UCS1);
114
909k
                max_char = MAX_CHAR_UCS2;
115
909k
                mask = MASK_UCS2;
116
909k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
1.88M
            continue;
119
2.01M
        }
120
31.7M
        p++;
121
31.7M
    }
122
18.0M
    return max_char;
123
18.1M
}
unicodeobject.c:ucs2lib_find_max_char
Line
Count
Source
61
26.8M
{
62
26.8M
#if STRINGLIB_SIZEOF_CHAR == 2
63
26.8M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
26.8M
    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
26.8M
    Py_UCS4 mask;
72
26.8M
    Py_ssize_t n = end - begin;
73
26.8M
    const STRINGLIB_CHAR *p = begin;
74
26.8M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
26.8M
    Py_UCS4 max_char;
76
77
26.8M
    max_char = MAX_CHAR_ASCII;
78
26.8M
    mask = MASK_ASCII;
79
1.07G
    while (p < unrolled_end) {
80
1.06G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
1.06G
        if (bits & mask) {
82
31.4M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
15.7M
                return max_char_limit;
85
15.7M
            }
86
15.7M
            if (mask == MASK_ASCII) {
87
15.7M
                max_char = MAX_CHAR_UCS1;
88
15.7M
                mask = MASK_UCS1;
89
15.7M
            }
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
15.7M
            continue;
98
31.4M
        }
99
1.03G
        p += 4;
100
1.03G
    }
101
31.0M
    while (p < end) {
102
21.1M
        if (p[0] & mask) {
103
2.37M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
1.15M
                return max_char_limit;
106
1.15M
            }
107
1.21M
            if (mask == MASK_ASCII) {
108
1.21M
                max_char = MAX_CHAR_UCS1;
109
1.21M
                mask = MASK_UCS1;
110
1.21M
            }
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
1.21M
            continue;
119
2.37M
        }
120
18.7M
        p++;
121
18.7M
    }
122
9.93M
    return max_char;
123
11.0M
}
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