Coverage Report

Created: 2025-07-04 06:49

/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
595M
# 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
50.7M
{
23
50.7M
    const unsigned char *p = (const unsigned char *) begin;
24
50.7M
    const unsigned char *_end = (const unsigned char *)end;
25
26
346M
    while (p < _end) {
27
316M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
47.1M
            const unsigned char *_p = p;
30
625M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
595M
                size_t value = *(const size_t *) _p;
32
595M
                if (value & UCS1_ASCII_CHAR_MASK)
33
17.1M
                    return 255;
34
578M
                _p += SIZEOF_SIZE_T;
35
578M
            }
36
30.0M
            p = _p;
37
30.0M
            if (p == _end)
38
516k
                break;
39
30.0M
        }
40
298M
        if (*p++ & 0x80)
41
3.50M
            return 255;
42
298M
    }
43
30.1M
    return 127;
44
50.7M
}
unicodeobject.c:ucs1lib_find_max_char
Line
Count
Source
22
50.7M
{
23
50.7M
    const unsigned char *p = (const unsigned char *) begin;
24
50.7M
    const unsigned char *_end = (const unsigned char *)end;
25
26
346M
    while (p < _end) {
27
316M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
47.1M
            const unsigned char *_p = p;
30
625M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
595M
                size_t value = *(const size_t *) _p;
32
595M
                if (value & UCS1_ASCII_CHAR_MASK)
33
17.1M
                    return 255;
34
578M
                _p += SIZEOF_SIZE_T;
35
578M
            }
36
30.0M
            p = _p;
37
30.0M
            if (p == _end)
38
516k
                break;
39
30.0M
        }
40
298M
        if (*p++ & 0x80)
41
3.50M
            return 255;
42
298M
    }
43
30.1M
    return 127;
44
50.7M
}
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
84.8M
#define MASK_ASCII 0xFFFFFF80
51
53.7M
#define MASK_UCS1 0xFFFFFF00
52
31.1M
#define MASK_UCS2 0xFFFF0000
53
54
54.5M
#define MAX_CHAR_ASCII 0x7f
55
24.4M
#define MAX_CHAR_UCS1  0xff
56
35.1M
#define MAX_CHAR_UCS2  0xffff
57
25.2M
#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
54.5M
{
62
#if STRINGLIB_SIZEOF_CHAR == 2
63
29.2M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
29.2M
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS2;
65
#elif STRINGLIB_SIZEOF_CHAR == 4
66
25.2M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
25.2M
    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
54.5M
    Py_UCS4 mask;
72
54.5M
    Py_ssize_t n = end - begin;
73
54.5M
    const STRINGLIB_CHAR *p = begin;
74
54.5M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
54.5M
    Py_UCS4 max_char;
76
77
54.5M
    max_char = MAX_CHAR_ASCII;
78
54.5M
    mask = MASK_ASCII;
79
2.37G
    while (p < unrolled_end) {
80
2.33G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
2.33G
        if (bits & mask) {
82
46.4M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
18.5M
                return max_char_limit;
85
18.5M
            }
86
27.8M
            if (mask == MASK_ASCII) {
87
22.7M
                max_char = MAX_CHAR_UCS1;
88
22.7M
                mask = MASK_UCS1;
89
22.7M
            }
90
5.10M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
5.10M
                assert(mask == MASK_UCS1);
93
5.10M
                max_char = MAX_CHAR_UCS2;
94
5.10M
                mask = MASK_UCS2;
95
5.10M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
27.8M
            continue;
98
46.4M
        }
99
2.28G
        p += 4;
100
2.28G
    }
101
114M
    while (p < end) {
102
79.3M
        if (p[0] & mask) {
103
3.34M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
889k
                return max_char_limit;
106
889k
            }
107
2.45M
            if (mask == MASK_ASCII) {
108
1.68M
                max_char = MAX_CHAR_UCS1;
109
1.68M
                mask = MASK_UCS1;
110
1.68M
            }
111
767k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
767k
                assert(mask == MASK_UCS1);
114
767k
                max_char = MAX_CHAR_UCS2;
115
767k
                mask = MASK_UCS2;
116
767k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
2.45M
            continue;
119
3.34M
        }
120
76.0M
        p++;
121
76.0M
    }
122
35.1M
    return max_char;
123
36.0M
}
unicodeobject.c:ucs4lib_find_max_char
Line
Count
Source
61
25.2M
{
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
25.2M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
25.2M
    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
25.2M
    Py_UCS4 mask;
72
25.2M
    Py_ssize_t n = end - begin;
73
25.2M
    const STRINGLIB_CHAR *p = begin;
74
25.2M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
25.2M
    Py_UCS4 max_char;
76
77
25.2M
    max_char = MAX_CHAR_ASCII;
78
25.2M
    mask = MASK_ASCII;
79
909M
    while (p < unrolled_end) {
80
886M
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
886M
        if (bits & mask) {
82
13.1M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
1.93M
                return max_char_limit;
85
1.93M
            }
86
11.1M
            if (mask == MASK_ASCII) {
87
6.09M
                max_char = MAX_CHAR_UCS1;
88
6.09M
                mask = MASK_UCS1;
89
6.09M
            }
90
5.10M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
5.10M
                assert(mask == MASK_UCS1);
93
5.10M
                max_char = MAX_CHAR_UCS2;
94
5.10M
                mask = MASK_UCS2;
95
5.10M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
11.1M
            continue;
98
13.1M
        }
99
873M
        p += 4;
100
873M
    }
101
75.7M
    while (p < end) {
102
52.5M
        if (p[0] & mask) {
103
1.72M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
88.8k
                return max_char_limit;
106
88.8k
            }
107
1.63M
            if (mask == MASK_ASCII) {
108
868k
                max_char = MAX_CHAR_UCS1;
109
868k
                mask = MASK_UCS1;
110
868k
            }
111
767k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
767k
                assert(mask == MASK_UCS1);
114
767k
                max_char = MAX_CHAR_UCS2;
115
767k
                mask = MASK_UCS2;
116
767k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
1.63M
            continue;
119
1.72M
        }
120
50.8M
        p++;
121
50.8M
    }
122
23.2M
    return max_char;
123
23.3M
}
unicodeobject.c:ucs2lib_find_max_char
Line
Count
Source
61
29.2M
{
62
29.2M
#if STRINGLIB_SIZEOF_CHAR == 2
63
29.2M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
29.2M
    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
29.2M
    Py_UCS4 mask;
72
29.2M
    Py_ssize_t n = end - begin;
73
29.2M
    const STRINGLIB_CHAR *p = begin;
74
29.2M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
29.2M
    Py_UCS4 max_char;
76
77
29.2M
    max_char = MAX_CHAR_ASCII;
78
29.2M
    mask = MASK_ASCII;
79
1.46G
    while (p < unrolled_end) {
80
1.44G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
1.44G
        if (bits & mask) {
82
33.2M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
16.6M
                return max_char_limit;
85
16.6M
            }
86
16.6M
            if (mask == MASK_ASCII) {
87
16.6M
                max_char = MAX_CHAR_UCS1;
88
16.6M
                mask = MASK_UCS1;
89
16.6M
            }
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
16.6M
            continue;
98
33.2M
        }
99
1.41G
        p += 4;
100
1.41G
    }
101
38.7M
    while (p < end) {
102
26.8M
        if (p[0] & mask) {
103
1.62M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
800k
                return max_char_limit;
106
800k
            }
107
820k
            if (mask == MASK_ASCII) {
108
820k
                max_char = MAX_CHAR_UCS1;
109
820k
                mask = MASK_UCS1;
110
820k
            }
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
820k
            continue;
119
1.62M
        }
120
25.2M
        p++;
121
25.2M
    }
122
11.8M
    return max_char;
123
12.6M
}
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