Coverage Report

Created: 2026-07-14 06:16

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
449M
# 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
43.2M
{
23
43.2M
    const unsigned char *p = (const unsigned char *) begin;
24
43.2M
    const unsigned char *_end = (const unsigned char *)end;
25
26
270M
    while (p < _end) {
27
238M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
36.0M
            const unsigned char *_p = p;
30
479M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
449M
                size_t value = *(const size_t *) _p;
32
449M
                if (value & UCS1_ASCII_CHAR_MASK)
33
6.20M
                    return 255;
34
443M
                _p += SIZEOF_SIZE_T;
35
443M
            }
36
29.8M
            p = _p;
37
29.8M
            if (p == _end)
38
826k
                break;
39
29.8M
        }
40
231M
        if (*p++ & 0x80)
41
3.61M
            return 255;
42
231M
    }
43
33.4M
    return 127;
44
43.2M
}
Unexecuted instantiation: unicode_writer.c:ucs1lib_find_max_char
unicodeobject.c:ucs1lib_find_max_char
Line
Count
Source
22
43.2M
{
23
43.2M
    const unsigned char *p = (const unsigned char *) begin;
24
43.2M
    const unsigned char *_end = (const unsigned char *)end;
25
26
270M
    while (p < _end) {
27
238M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
36.0M
            const unsigned char *_p = p;
30
479M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
449M
                size_t value = *(const size_t *) _p;
32
449M
                if (value & UCS1_ASCII_CHAR_MASK)
33
6.20M
                    return 255;
34
443M
                _p += SIZEOF_SIZE_T;
35
443M
            }
36
29.8M
            p = _p;
37
29.8M
            if (p == _end)
38
826k
                break;
39
29.8M
        }
40
231M
        if (*p++ & 0x80)
41
3.61M
            return 255;
42
231M
    }
43
33.4M
    return 127;
44
43.2M
}
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
72.3M
#define MASK_ASCII 0xFFFFFF80
51
50.7M
#define MASK_UCS1 0xFFFFFF00
52
21.5M
#define MASK_UCS2 0xFFFF0000
53
54
44.3M
#define MAX_CHAR_ASCII 0x7f
55
23.1M
#define MAX_CHAR_UCS1  0xff
56
32.5M
#define MAX_CHAR_UCS2  0xffff
57
16.6M
#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
44.3M
{
62
#if STRINGLIB_SIZEOF_CHAR == 2
63
27.6M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
27.6M
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS2;
65
#elif STRINGLIB_SIZEOF_CHAR == 4
66
16.6M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
16.6M
    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
44.3M
    Py_UCS4 mask;
72
44.3M
    Py_ssize_t n = end - begin;
73
44.3M
    const STRINGLIB_CHAR *p = begin;
74
44.3M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
44.3M
    Py_UCS4 max_char;
76
77
44.3M
    max_char = MAX_CHAR_ASCII;
78
44.3M
    mask = MASK_ASCII;
79
1.81G
    while (p < unrolled_end) {
80
1.78G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
1.78G
        if (bits & mask) {
82
42.2M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
17.4M
                return max_char_limit;
85
17.4M
            }
86
24.8M
            if (mask == MASK_ASCII) {
87
20.9M
                max_char = MAX_CHAR_UCS1;
88
20.9M
                mask = MASK_UCS1;
89
20.9M
            }
90
3.91M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
3.91M
                assert(mask == MASK_UCS1);
93
3.91M
                max_char = MAX_CHAR_UCS2;
94
3.91M
                mask = MASK_UCS2;
95
3.91M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
24.8M
            continue;
98
42.2M
        }
99
1.74G
        p += 4;
100
1.74G
    }
101
77.0M
    while (p < end) {
102
51.3M
        if (p[0] & mask) {
103
4.38M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
1.24M
                return max_char_limit;
106
1.24M
            }
107
3.14M
            if (mask == MASK_ASCII) {
108
2.17M
                max_char = MAX_CHAR_UCS1;
109
2.17M
                mask = MASK_UCS1;
110
2.17M
            }
111
971k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
971k
                assert(mask == MASK_UCS1);
114
971k
                max_char = MAX_CHAR_UCS2;
115
971k
                mask = MASK_UCS2;
116
971k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
3.14M
            continue;
119
4.38M
        }
120
46.9M
        p++;
121
46.9M
    }
122
25.6M
    return max_char;
123
26.8M
}
unicodeobject.c:ucs4lib_find_max_char
Line
Count
Source
61
16.6M
{
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
16.6M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
16.6M
    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
16.6M
    Py_UCS4 mask;
72
16.6M
    Py_ssize_t n = end - begin;
73
16.6M
    const STRINGLIB_CHAR *p = begin;
74
16.6M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
16.6M
    Py_UCS4 max_char;
76
77
16.6M
    max_char = MAX_CHAR_ASCII;
78
16.6M
    mask = MASK_ASCII;
79
825M
    while (p < unrolled_end) {
80
809M
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
809M
        if (bits & mask) {
82
10.1M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
1.37M
                return max_char_limit;
85
1.37M
            }
86
8.74M
            if (mask == MASK_ASCII) {
87
4.83M
                max_char = MAX_CHAR_UCS1;
88
4.83M
                mask = MASK_UCS1;
89
4.83M
            }
90
3.91M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
3.91M
                assert(mask == MASK_UCS1);
93
3.91M
                max_char = MAX_CHAR_UCS2;
94
3.91M
                mask = MASK_UCS2;
95
3.91M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
8.74M
            continue;
98
10.1M
        }
99
799M
        p += 4;
100
799M
    }
101
44.9M
    while (p < end) {
102
29.8M
        if (p[0] & mask) {
103
2.17M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
163k
                return max_char_limit;
106
163k
            }
107
2.01M
            if (mask == MASK_ASCII) {
108
1.04M
                max_char = MAX_CHAR_UCS1;
109
1.04M
                mask = MASK_UCS1;
110
1.04M
            }
111
971k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
971k
                assert(mask == MASK_UCS1);
114
971k
                max_char = MAX_CHAR_UCS2;
115
971k
                mask = MASK_UCS2;
116
971k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
2.01M
            continue;
119
2.17M
        }
120
27.6M
        p++;
121
27.6M
    }
122
15.1M
    return max_char;
123
15.2M
}
unicodeobject.c:ucs2lib_find_max_char
Line
Count
Source
61
27.6M
{
62
27.6M
#if STRINGLIB_SIZEOF_CHAR == 2
63
27.6M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
27.6M
    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
27.6M
    Py_UCS4 mask;
72
27.6M
    Py_ssize_t n = end - begin;
73
27.6M
    const STRINGLIB_CHAR *p = begin;
74
27.6M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
27.6M
    Py_UCS4 max_char;
76
77
27.6M
    max_char = MAX_CHAR_ASCII;
78
27.6M
    mask = MASK_ASCII;
79
990M
    while (p < unrolled_end) {
80
979M
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
979M
        if (bits & mask) {
82
32.1M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
16.0M
                return max_char_limit;
85
16.0M
            }
86
16.1M
            if (mask == MASK_ASCII) {
87
16.1M
                max_char = MAX_CHAR_UCS1;
88
16.1M
                mask = MASK_UCS1;
89
16.1M
            }
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
16.1M
            continue;
98
32.1M
        }
99
946M
        p += 4;
100
946M
    }
101
32.0M
    while (p < end) {
102
21.5M
        if (p[0] & mask) {
103
2.20M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
1.07M
                return max_char_limit;
106
1.07M
            }
107
1.13M
            if (mask == MASK_ASCII) {
108
1.13M
                max_char = MAX_CHAR_UCS1;
109
1.13M
                mask = MASK_UCS1;
110
1.13M
            }
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
1.13M
            continue;
119
2.20M
        }
120
19.3M
        p++;
121
19.3M
    }
122
10.5M
    return max_char;
123
11.5M
}
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