Coverage Report

Created: 2026-06-21 06:15

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
460M
# 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
43.1M
{
23
43.1M
    const unsigned char *p = (const unsigned char *) begin;
24
43.1M
    const unsigned char *_end = (const unsigned char *)end;
25
26
275M
    while (p < _end) {
27
242M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
36.2M
            const unsigned char *_p = p;
30
490M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
460M
                size_t value = *(const size_t *) _p;
32
460M
                if (value & UCS1_ASCII_CHAR_MASK)
33
6.16M
                    return 255;
34
454M
                _p += SIZEOF_SIZE_T;
35
454M
            }
36
30.0M
            p = _p;
37
30.0M
            if (p == _end)
38
748k
                break;
39
30.0M
        }
40
236M
        if (*p++ & 0x80)
41
3.59M
            return 255;
42
236M
    }
43
33.3M
    return 127;
44
43.1M
}
Unexecuted instantiation: unicode_writer.c:ucs1lib_find_max_char
unicodeobject.c:ucs1lib_find_max_char
Line
Count
Source
22
43.1M
{
23
43.1M
    const unsigned char *p = (const unsigned char *) begin;
24
43.1M
    const unsigned char *_end = (const unsigned char *)end;
25
26
275M
    while (p < _end) {
27
242M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
36.2M
            const unsigned char *_p = p;
30
490M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
460M
                size_t value = *(const size_t *) _p;
32
460M
                if (value & UCS1_ASCII_CHAR_MASK)
33
6.16M
                    return 255;
34
454M
                _p += SIZEOF_SIZE_T;
35
454M
            }
36
30.0M
            p = _p;
37
30.0M
            if (p == _end)
38
748k
                break;
39
30.0M
        }
40
236M
        if (*p++ & 0x80)
41
3.59M
            return 255;
42
236M
    }
43
33.3M
    return 127;
44
43.1M
}
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
70.4M
#define MASK_ASCII 0xFFFFFF80
51
48.3M
#define MASK_UCS1 0xFFFFFF00
52
22.0M
#define MASK_UCS2 0xFFFF0000
53
54
43.5M
#define MAX_CHAR_ASCII 0x7f
55
21.9M
#define MAX_CHAR_UCS1  0xff
56
31.4M
#define MAX_CHAR_UCS2  0xffff
57
17.0M
#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
43.5M
{
62
#if STRINGLIB_SIZEOF_CHAR == 2
63
26.4M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
26.4M
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS2;
65
#elif STRINGLIB_SIZEOF_CHAR == 4
66
17.0M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
17.0M
    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
43.5M
    Py_UCS4 mask;
72
43.5M
    Py_ssize_t n = end - begin;
73
43.5M
    const STRINGLIB_CHAR *p = begin;
74
43.5M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
43.5M
    Py_UCS4 max_char;
76
77
43.5M
    max_char = MAX_CHAR_ASCII;
78
43.5M
    mask = MASK_ASCII;
79
1.74G
    while (p < unrolled_end) {
80
1.71G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
1.71G
        if (bits & mask) {
82
40.0M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
16.2M
                return max_char_limit;
85
16.2M
            }
86
23.8M
            if (mask == MASK_ASCII) {
87
19.7M
                max_char = MAX_CHAR_UCS1;
88
19.7M
                mask = MASK_UCS1;
89
19.7M
            }
90
4.01M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
4.01M
                assert(mask == MASK_UCS1);
93
4.01M
                max_char = MAX_CHAR_UCS2;
94
4.01M
                mask = MASK_UCS2;
95
4.01M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
23.8M
            continue;
98
40.0M
        }
99
1.67G
        p += 4;
100
1.67G
    }
101
78.0M
    while (p < end) {
102
51.9M
        if (p[0] & mask) {
103
4.29M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
1.19M
                return max_char_limit;
106
1.19M
            }
107
3.09M
            if (mask == MASK_ASCII) {
108
2.14M
                max_char = MAX_CHAR_UCS1;
109
2.14M
                mask = MASK_UCS1;
110
2.14M
            }
111
959k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
959k
                assert(mask == MASK_UCS1);
114
959k
                max_char = MAX_CHAR_UCS2;
115
959k
                mask = MASK_UCS2;
116
959k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
3.09M
            continue;
119
4.29M
        }
120
47.6M
        p++;
121
47.6M
    }
122
26.0M
    return max_char;
123
27.2M
}
unicodeobject.c:ucs4lib_find_max_char
Line
Count
Source
61
17.0M
{
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
17.0M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
17.0M
    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
17.0M
    Py_UCS4 mask;
72
17.0M
    Py_ssize_t n = end - begin;
73
17.0M
    const STRINGLIB_CHAR *p = begin;
74
17.0M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
17.0M
    Py_UCS4 max_char;
76
77
17.0M
    max_char = MAX_CHAR_ASCII;
78
17.0M
    mask = MASK_ASCII;
79
806M
    while (p < unrolled_end) {
80
790M
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
790M
        if (bits & mask) {
82
10.3M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
1.39M
                return max_char_limit;
85
1.39M
            }
86
8.92M
            if (mask == MASK_ASCII) {
87
4.90M
                max_char = MAX_CHAR_UCS1;
88
4.90M
                mask = MASK_UCS1;
89
4.90M
            }
90
4.01M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
4.01M
                assert(mask == MASK_UCS1);
93
4.01M
                max_char = MAX_CHAR_UCS2;
94
4.01M
                mask = MASK_UCS2;
95
4.01M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
8.92M
            continue;
98
10.3M
        }
99
780M
        p += 4;
100
780M
    }
101
45.7M
    while (p < end) {
102
30.2M
        if (p[0] & mask) {
103
2.13M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
142k
                return max_char_limit;
106
142k
            }
107
1.98M
            if (mask == MASK_ASCII) {
108
1.03M
                max_char = MAX_CHAR_UCS1;
109
1.03M
                mask = MASK_UCS1;
110
1.03M
            }
111
959k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
959k
                assert(mask == MASK_UCS1);
114
959k
                max_char = MAX_CHAR_UCS2;
115
959k
                mask = MASK_UCS2;
116
959k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
1.98M
            continue;
119
2.13M
        }
120
28.0M
        p++;
121
28.0M
    }
122
15.5M
    return max_char;
123
15.6M
}
unicodeobject.c:ucs2lib_find_max_char
Line
Count
Source
61
26.4M
{
62
26.4M
#if STRINGLIB_SIZEOF_CHAR == 2
63
26.4M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
26.4M
    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
26.4M
    Py_UCS4 mask;
72
26.4M
    Py_ssize_t n = end - begin;
73
26.4M
    const STRINGLIB_CHAR *p = begin;
74
26.4M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
26.4M
    Py_UCS4 max_char;
76
77
26.4M
    max_char = MAX_CHAR_ASCII;
78
26.4M
    mask = MASK_ASCII;
79
938M
    while (p < unrolled_end) {
80
927M
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
927M
        if (bits & mask) {
82
29.7M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
14.8M
                return max_char_limit;
85
14.8M
            }
86
14.8M
            if (mask == MASK_ASCII) {
87
14.8M
                max_char = MAX_CHAR_UCS1;
88
14.8M
                mask = MASK_UCS1;
89
14.8M
            }
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
14.8M
            continue;
98
29.7M
        }
99
897M
        p += 4;
100
897M
    }
101
32.2M
    while (p < end) {
102
21.7M
        if (p[0] & mask) {
103
2.16M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
1.05M
                return max_char_limit;
106
1.05M
            }
107
1.10M
            if (mask == MASK_ASCII) {
108
1.10M
                max_char = MAX_CHAR_UCS1;
109
1.10M
                mask = MASK_UCS1;
110
1.10M
            }
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
1.10M
            continue;
119
2.16M
        }
120
19.5M
        p++;
121
19.5M
    }
122
10.5M
    return max_char;
123
11.6M
}
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