Coverage Report

Created: 2026-02-26 06:53

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
136M
# 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
258M
    while (p < _end) {
27
227M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
34.0M
            const unsigned char *_p = p;
30
165M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
136M
                size_t value = *(const size_t *) _p;
32
136M
                if (value & UCS1_ASCII_CHAR_MASK)
33
4.62M
                    return 255;
34
131M
                _p += SIZEOF_SIZE_T;
35
131M
            }
36
29.3M
            p = _p;
37
29.3M
            if (p == _end)
38
830k
                break;
39
29.3M
        }
40
221M
        if (*p++ & 0x80)
41
3.30M
            return 255;
42
221M
    }
43
32.7M
    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
258M
    while (p < _end) {
27
227M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
34.0M
            const unsigned char *_p = p;
30
165M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
136M
                size_t value = *(const size_t *) _p;
32
136M
                if (value & UCS1_ASCII_CHAR_MASK)
33
4.62M
                    return 255;
34
131M
                _p += SIZEOF_SIZE_T;
35
131M
            }
36
29.3M
            p = _p;
37
29.3M
            if (p == _end)
38
830k
                break;
39
29.3M
        }
40
221M
        if (*p++ & 0x80)
41
3.30M
            return 255;
42
221M
    }
43
32.7M
    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
86.2M
#define MASK_ASCII 0xFFFFFF80
51
58.3M
#define MASK_UCS1 0xFFFFFF00
52
27.8M
#define MASK_UCS2 0xFFFF0000
53
54
52.6M
#define MAX_CHAR_ASCII 0x7f
55
27.0M
#define MAX_CHAR_UCS1  0xff
56
37.8M
#define MAX_CHAR_UCS2  0xffff
57
21.3M
#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
52.6M
{
62
#if STRINGLIB_SIZEOF_CHAR == 2
63
31.3M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
31.3M
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS2;
65
#elif STRINGLIB_SIZEOF_CHAR == 4
66
21.3M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
21.3M
    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
52.6M
    Py_UCS4 mask;
72
52.6M
    Py_ssize_t n = end - begin;
73
52.6M
    const STRINGLIB_CHAR *p = begin;
74
52.6M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
52.6M
    Py_UCS4 max_char;
76
77
52.6M
    max_char = MAX_CHAR_ASCII;
78
52.6M
    mask = MASK_ASCII;
79
1.77G
    while (p < unrolled_end) {
80
1.74G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
1.74G
        if (bits & mask) {
82
50.5M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
19.5M
                return max_char_limit;
85
19.5M
            }
86
30.9M
            if (mask == MASK_ASCII) {
87
25.1M
                max_char = MAX_CHAR_UCS1;
88
25.1M
                mask = MASK_UCS1;
89
25.1M
            }
90
5.79M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
5.79M
                assert(mask == MASK_UCS1);
93
5.79M
                max_char = MAX_CHAR_UCS2;
94
5.79M
                mask = MASK_UCS2;
95
5.79M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
30.9M
            continue;
98
50.5M
        }
99
1.69G
        p += 4;
100
1.69G
    }
101
92.6M
    while (p < end) {
102
60.7M
        if (p[0] & mask) {
103
3.80M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
1.14M
                return max_char_limit;
106
1.14M
            }
107
2.66M
            if (mask == MASK_ASCII) {
108
1.90M
                max_char = MAX_CHAR_UCS1;
109
1.90M
                mask = MASK_UCS1;
110
1.90M
            }
111
757k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
757k
                assert(mask == MASK_UCS1);
114
757k
                max_char = MAX_CHAR_UCS2;
115
757k
                mask = MASK_UCS2;
116
757k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
2.66M
            continue;
119
3.80M
        }
120
56.9M
        p++;
121
56.9M
    }
122
31.9M
    return max_char;
123
33.0M
}
unicodeobject.c:ucs4lib_find_max_char
Line
Count
Source
61
21.3M
{
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
21.3M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
21.3M
    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
21.3M
    Py_UCS4 mask;
72
21.3M
    Py_ssize_t n = end - begin;
73
21.3M
    const STRINGLIB_CHAR *p = begin;
74
21.3M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
21.3M
    Py_UCS4 max_char;
76
77
21.3M
    max_char = MAX_CHAR_ASCII;
78
21.3M
    mask = MASK_ASCII;
79
607M
    while (p < unrolled_end) {
80
587M
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
587M
        if (bits & mask) {
82
13.7M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
1.25M
                return max_char_limit;
85
1.25M
            }
86
12.5M
            if (mask == MASK_ASCII) {
87
6.74M
                max_char = MAX_CHAR_UCS1;
88
6.74M
                mask = MASK_UCS1;
89
6.74M
            }
90
5.79M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
5.79M
                assert(mask == MASK_UCS1);
93
5.79M
                max_char = MAX_CHAR_UCS2;
94
5.79M
                mask = MASK_UCS2;
95
5.79M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
12.5M
            continue;
98
13.7M
        }
99
573M
        p += 4;
100
573M
    }
101
57.1M
    while (p < end) {
102
37.1M
        if (p[0] & mask) {
103
1.69M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
105k
                return max_char_limit;
106
105k
            }
107
1.58M
            if (mask == MASK_ASCII) {
108
827k
                max_char = MAX_CHAR_UCS1;
109
827k
                mask = MASK_UCS1;
110
827k
            }
111
757k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
757k
                assert(mask == MASK_UCS1);
114
757k
                max_char = MAX_CHAR_UCS2;
115
757k
                mask = MASK_UCS2;
116
757k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
1.58M
            continue;
119
1.69M
        }
120
35.4M
        p++;
121
35.4M
    }
122
19.9M
    return max_char;
123
20.0M
}
unicodeobject.c:ucs2lib_find_max_char
Line
Count
Source
61
31.3M
{
62
31.3M
#if STRINGLIB_SIZEOF_CHAR == 2
63
31.3M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
31.3M
    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
31.3M
    Py_UCS4 mask;
72
31.3M
    Py_ssize_t n = end - begin;
73
31.3M
    const STRINGLIB_CHAR *p = begin;
74
31.3M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
31.3M
    Py_UCS4 max_char;
76
77
31.3M
    max_char = MAX_CHAR_ASCII;
78
31.3M
    mask = MASK_ASCII;
79
1.17G
    while (p < unrolled_end) {
80
1.15G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
1.15G
        if (bits & mask) {
82
36.7M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
18.3M
                return max_char_limit;
85
18.3M
            }
86
18.3M
            if (mask == MASK_ASCII) {
87
18.3M
                max_char = MAX_CHAR_UCS1;
88
18.3M
                mask = MASK_UCS1;
89
18.3M
            }
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
18.3M
            continue;
98
36.7M
        }
99
1.12G
        p += 4;
100
1.12G
    }
101
35.5M
    while (p < end) {
102
23.5M
        if (p[0] & mask) {
103
2.11M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
1.03M
                return max_char_limit;
106
1.03M
            }
107
1.08M
            if (mask == MASK_ASCII) {
108
1.08M
                max_char = MAX_CHAR_UCS1;
109
1.08M
                mask = MASK_UCS1;
110
1.08M
            }
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
1.08M
            continue;
119
2.11M
        }
120
21.4M
        p++;
121
21.4M
    }
122
11.9M
    return max_char;
123
12.9M
}
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