Coverage Report

Created: 2026-10-31 06:21

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
218M
# 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
41.3M
{
23
41.3M
    const unsigned char *p = (const unsigned char *) begin;
24
41.3M
    const unsigned char *_end = (const unsigned char *)end;
25
26
248M
    while (p < _end) {
27
217M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
34.4M
            const unsigned char *_p = p;
30
247M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
218M
                size_t value = *(const size_t *) _p;
32
218M
                if (value & UCS1_ASCII_CHAR_MASK)
33
6.07M
                    return 255;
34
212M
                _p += SIZEOF_SIZE_T;
35
212M
            }
36
28.3M
            p = _p;
37
28.3M
            if (p == _end)
38
832k
                break;
39
28.3M
        }
40
210M
        if (*p++ & 0x80)
41
4.07M
            return 255;
42
210M
    }
43
31.2M
    return 127;
44
41.3M
}
Unexecuted instantiation: unicode_writer.c:ucs1lib_find_max_char
unicodeobject.c:ucs1lib_find_max_char
Line
Count
Source
22
41.3M
{
23
41.3M
    const unsigned char *p = (const unsigned char *) begin;
24
41.3M
    const unsigned char *_end = (const unsigned char *)end;
25
26
248M
    while (p < _end) {
27
217M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
34.4M
            const unsigned char *_p = p;
30
247M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
218M
                size_t value = *(const size_t *) _p;
32
218M
                if (value & UCS1_ASCII_CHAR_MASK)
33
6.07M
                    return 255;
34
212M
                _p += SIZEOF_SIZE_T;
35
212M
            }
36
28.3M
            p = _p;
37
28.3M
            if (p == _end)
38
832k
                break;
39
28.3M
        }
40
210M
        if (*p++ & 0x80)
41
4.07M
            return 255;
42
210M
    }
43
31.2M
    return 127;
44
41.3M
}
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
69.5M
#define MASK_ASCII 0xFFFFFF80
51
46.7M
#define MASK_UCS1 0xFFFFFF00
52
22.8M
#define MASK_UCS2 0xFFFF0000
53
54
38.5M
#define MAX_CHAR_ASCII 0x7f
55
24.6M
#define MAX_CHAR_UCS1  0xff
56
28.4M
#define MAX_CHAR_UCS2  0xffff
57
16.4M
#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
38.5M
{
62
#if STRINGLIB_SIZEOF_CHAR == 2
63
22.0M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
22.0M
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS2;
65
#elif STRINGLIB_SIZEOF_CHAR == 4
66
16.4M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
16.4M
    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
38.5M
    Py_UCS4 mask;
72
38.5M
    Py_ssize_t n = end - begin;
73
38.5M
    const STRINGLIB_CHAR *p = begin;
74
38.5M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
38.5M
    Py_UCS4 max_char;
76
77
38.5M
    max_char = MAX_CHAR_ASCII;
78
38.5M
    mask = MASK_ASCII;
79
2.12G
    while (p < unrolled_end) {
80
2.10G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
2.10G
        if (bits & mask) {
82
43.4M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
16.8M
                return max_char_limit;
85
16.8M
            }
86
26.6M
            if (mask == MASK_ASCII) {
87
21.5M
                max_char = MAX_CHAR_UCS1;
88
21.5M
                mask = MASK_UCS1;
89
21.5M
            }
90
5.11M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
5.11M
                assert(mask == MASK_UCS1);
93
5.11M
                max_char = MAX_CHAR_UCS2;
94
5.11M
                mask = MASK_UCS2;
95
5.11M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
26.6M
            continue;
98
43.4M
        }
99
2.06G
        p += 4;
100
2.06G
    }
101
59.6M
    while (p < end) {
102
39.8M
        if (p[0] & mask) {
103
6.30M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
1.83M
                return max_char_limit;
106
1.83M
            }
107
4.47M
            if (mask == MASK_ASCII) {
108
3.16M
                max_char = MAX_CHAR_UCS1;
109
3.16M
                mask = MASK_UCS1;
110
3.16M
            }
111
1.30M
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
1.30M
                assert(mask == MASK_UCS1);
114
1.30M
                max_char = MAX_CHAR_UCS2;
115
1.30M
                mask = MASK_UCS2;
116
1.30M
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
4.47M
            continue;
119
6.30M
        }
120
33.5M
        p++;
121
33.5M
    }
122
19.8M
    return max_char;
123
21.6M
}
unicodeobject.c:ucs4lib_find_max_char
Line
Count
Source
61
16.4M
{
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
16.4M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
16.4M
    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
16.4M
    Py_UCS4 mask;
72
16.4M
    Py_ssize_t n = end - begin;
73
16.4M
    const STRINGLIB_CHAR *p = begin;
74
16.4M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
16.4M
    Py_UCS4 max_char;
76
77
16.4M
    max_char = MAX_CHAR_ASCII;
78
16.4M
    mask = MASK_ASCII;
79
718M
    while (p < unrolled_end) {
80
703M
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
703M
        if (bits & mask) {
82
12.6M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
1.48M
                return max_char_limit;
85
1.48M
            }
86
11.1M
            if (mask == MASK_ASCII) {
87
6.07M
                max_char = MAX_CHAR_UCS1;
88
6.07M
                mask = MASK_UCS1;
89
6.07M
            }
90
5.11M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
5.11M
                assert(mask == MASK_UCS1);
93
5.11M
                max_char = MAX_CHAR_UCS2;
94
5.11M
                mask = MASK_UCS2;
95
5.11M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
11.1M
            continue;
98
12.6M
        }
99
690M
        p += 4;
100
690M
    }
101
42.7M
    while (p < end) {
102
27.9M
        if (p[0] & mask) {
103
2.85M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
132k
                return max_char_limit;
106
132k
            }
107
2.72M
            if (mask == MASK_ASCII) {
108
1.41M
                max_char = MAX_CHAR_UCS1;
109
1.41M
                mask = MASK_UCS1;
110
1.41M
            }
111
1.30M
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
1.30M
                assert(mask == MASK_UCS1);
114
1.30M
                max_char = MAX_CHAR_UCS2;
115
1.30M
                mask = MASK_UCS2;
116
1.30M
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
2.72M
            continue;
119
2.85M
        }
120
25.0M
        p++;
121
25.0M
    }
122
14.8M
    return max_char;
123
14.9M
}
unicodeobject.c:ucs2lib_find_max_char
Line
Count
Source
61
22.0M
{
62
22.0M
#if STRINGLIB_SIZEOF_CHAR == 2
63
22.0M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
22.0M
    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
22.0M
    Py_UCS4 mask;
72
22.0M
    Py_ssize_t n = end - begin;
73
22.0M
    const STRINGLIB_CHAR *p = begin;
74
22.0M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
22.0M
    Py_UCS4 max_char;
76
77
22.0M
    max_char = MAX_CHAR_ASCII;
78
22.0M
    mask = MASK_ASCII;
79
1.41G
    while (p < unrolled_end) {
80
1.40G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
1.40G
        if (bits & mask) {
82
30.7M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
15.3M
                return max_char_limit;
85
15.3M
            }
86
15.4M
            if (mask == MASK_ASCII) {
87
15.4M
                max_char = MAX_CHAR_UCS1;
88
15.4M
                mask = MASK_UCS1;
89
15.4M
            }
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
15.4M
            continue;
98
30.7M
        }
99
1.37G
        p += 4;
100
1.37G
    }
101
16.8M
    while (p < end) {
102
11.8M
        if (p[0] & mask) {
103
3.44M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
1.70M
                return max_char_limit;
106
1.70M
            }
107
1.74M
            if (mask == MASK_ASCII) {
108
1.74M
                max_char = MAX_CHAR_UCS1;
109
1.74M
                mask = MASK_UCS1;
110
1.74M
            }
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
1.74M
            continue;
119
3.44M
        }
120
8.45M
        p++;
121
8.45M
    }
122
4.98M
    return max_char;
123
6.68M
}
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