Coverage Report

Created: 2026-10-17 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
224M
# 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
40.6M
{
23
40.6M
    const unsigned char *p = (const unsigned char *) begin;
24
40.6M
    const unsigned char *_end = (const unsigned char *)end;
25
26
244M
    while (p < _end) {
27
214M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
33.7M
            const unsigned char *_p = p;
30
252M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
224M
                size_t value = *(const size_t *) _p;
32
224M
                if (value & UCS1_ASCII_CHAR_MASK)
33
6.16M
                    return 255;
34
218M
                _p += SIZEOF_SIZE_T;
35
218M
            }
36
27.5M
            p = _p;
37
27.5M
            if (p == _end)
38
716k
                break;
39
27.5M
        }
40
207M
        if (*p++ & 0x80)
41
3.56M
            return 255;
42
207M
    }
43
30.9M
    return 127;
44
40.6M
}
Unexecuted instantiation: unicode_writer.c:ucs1lib_find_max_char
unicodeobject.c:ucs1lib_find_max_char
Line
Count
Source
22
40.6M
{
23
40.6M
    const unsigned char *p = (const unsigned char *) begin;
24
40.6M
    const unsigned char *_end = (const unsigned char *)end;
25
26
244M
    while (p < _end) {
27
214M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
33.7M
            const unsigned char *_p = p;
30
252M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
224M
                size_t value = *(const size_t *) _p;
32
224M
                if (value & UCS1_ASCII_CHAR_MASK)
33
6.16M
                    return 255;
34
218M
                _p += SIZEOF_SIZE_T;
35
218M
            }
36
27.5M
            p = _p;
37
27.5M
            if (p == _end)
38
716k
                break;
39
27.5M
        }
40
207M
        if (*p++ & 0x80)
41
3.56M
            return 255;
42
207M
    }
43
30.9M
    return 127;
44
40.6M
}
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
64.6M
#define MASK_ASCII 0xFFFFFF80
51
42.1M
#define MASK_UCS1 0xFFFFFF00
52
22.5M
#define MASK_UCS2 0xFFFF0000
53
54
35.9M
#define MAX_CHAR_ASCII 0x7f
55
22.3M
#define MAX_CHAR_UCS1  0xff
56
26.0M
#define MAX_CHAR_UCS2  0xffff
57
16.2M
#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
35.9M
{
62
#if STRINGLIB_SIZEOF_CHAR == 2
63
19.7M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
19.7M
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS2;
65
#elif STRINGLIB_SIZEOF_CHAR == 4
66
16.2M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
16.2M
    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
35.9M
    Py_UCS4 mask;
72
35.9M
    Py_ssize_t n = end - begin;
73
35.9M
    const STRINGLIB_CHAR *p = begin;
74
35.9M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
35.9M
    Py_UCS4 max_char;
76
77
35.9M
    max_char = MAX_CHAR_ASCII;
78
35.9M
    mask = MASK_ASCII;
79
1.71G
    while (p < unrolled_end) {
80
1.69G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
1.69G
        if (bits & mask) {
82
39.5M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
14.9M
                return max_char_limit;
85
14.9M
            }
86
24.5M
            if (mask == MASK_ASCII) {
87
19.5M
                max_char = MAX_CHAR_UCS1;
88
19.5M
                mask = MASK_UCS1;
89
19.5M
            }
90
5.00M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
5.00M
                assert(mask == MASK_UCS1);
93
5.00M
                max_char = MAX_CHAR_UCS2;
94
5.00M
                mask = MASK_UCS2;
95
5.00M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
24.5M
            continue;
98
39.5M
        }
99
1.65G
        p += 4;
100
1.65G
    }
101
58.9M
    while (p < end) {
102
39.4M
        if (p[0] & mask) {
103
5.60M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
1.52M
                return max_char_limit;
106
1.52M
            }
107
4.07M
            if (mask == MASK_ASCII) {
108
2.80M
                max_char = MAX_CHAR_UCS1;
109
2.80M
                mask = MASK_UCS1;
110
2.80M
            }
111
1.27M
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
1.27M
                assert(mask == MASK_UCS1);
114
1.27M
                max_char = MAX_CHAR_UCS2;
115
1.27M
                mask = MASK_UCS2;
116
1.27M
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
4.07M
            continue;
119
5.60M
        }
120
33.8M
        p++;
121
33.8M
    }
122
19.4M
    return max_char;
123
21.0M
}
unicodeobject.c:ucs4lib_find_max_char
Line
Count
Source
61
16.2M
{
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
16.2M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
16.2M
    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
16.2M
    Py_UCS4 mask;
72
16.2M
    Py_ssize_t n = end - begin;
73
16.2M
    const STRINGLIB_CHAR *p = begin;
74
16.2M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
16.2M
    Py_UCS4 max_char;
76
77
16.2M
    max_char = MAX_CHAR_ASCII;
78
16.2M
    mask = MASK_ASCII;
79
769M
    while (p < unrolled_end) {
80
754M
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
754M
        if (bits & mask) {
82
12.2M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
1.38M
                return max_char_limit;
85
1.38M
            }
86
10.9M
            if (mask == MASK_ASCII) {
87
5.90M
                max_char = MAX_CHAR_UCS1;
88
5.90M
                mask = MASK_UCS1;
89
5.90M
            }
90
5.00M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
5.00M
                assert(mask == MASK_UCS1);
93
5.00M
                max_char = MAX_CHAR_UCS2;
94
5.00M
                mask = MASK_UCS2;
95
5.00M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
10.9M
            continue;
98
12.2M
        }
99
742M
        p += 4;
100
742M
    }
101
42.8M
    while (p < end) {
102
28.1M
        if (p[0] & mask) {
103
2.80M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
148k
                return max_char_limit;
106
148k
            }
107
2.65M
            if (mask == MASK_ASCII) {
108
1.37M
                max_char = MAX_CHAR_UCS1;
109
1.37M
                mask = MASK_UCS1;
110
1.37M
            }
111
1.27M
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
1.27M
                assert(mask == MASK_UCS1);
114
1.27M
                max_char = MAX_CHAR_UCS2;
115
1.27M
                mask = MASK_UCS2;
116
1.27M
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
2.65M
            continue;
119
2.80M
        }
120
25.3M
        p++;
121
25.3M
    }
122
14.7M
    return max_char;
123
14.8M
}
unicodeobject.c:ucs2lib_find_max_char
Line
Count
Source
61
19.7M
{
62
19.7M
#if STRINGLIB_SIZEOF_CHAR == 2
63
19.7M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
19.7M
    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
19.7M
    Py_UCS4 mask;
72
19.7M
    Py_ssize_t n = end - begin;
73
19.7M
    const STRINGLIB_CHAR *p = begin;
74
19.7M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
19.7M
    Py_UCS4 max_char;
76
77
19.7M
    max_char = MAX_CHAR_ASCII;
78
19.7M
    mask = MASK_ASCII;
79
948M
    while (p < unrolled_end) {
80
942M
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
942M
        if (bits & mask) {
82
27.2M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
13.5M
                return max_char_limit;
85
13.5M
            }
86
13.6M
            if (mask == MASK_ASCII) {
87
13.6M
                max_char = MAX_CHAR_UCS1;
88
13.6M
                mask = MASK_UCS1;
89
13.6M
            }
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
13.6M
            continue;
98
27.2M
        }
99
915M
        p += 4;
100
915M
    }
101
16.0M
    while (p < end) {
102
11.2M
        if (p[0] & mask) {
103
2.80M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
1.37M
                return max_char_limit;
106
1.37M
            }
107
1.42M
            if (mask == MASK_ASCII) {
108
1.42M
                max_char = MAX_CHAR_UCS1;
109
1.42M
                mask = MASK_UCS1;
110
1.42M
            }
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
1.42M
            continue;
119
2.80M
        }
120
8.43M
        p++;
121
8.43M
    }
122
4.77M
    return max_char;
123
6.15M
}
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