Coverage Report

Created: 2025-09-04 06:25

/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
580M
# 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
49.7M
{
23
49.7M
    const unsigned char *p = (const unsigned char *) begin;
24
49.7M
    const unsigned char *_end = (const unsigned char *)end;
25
26
334M
    while (p < _end) {
27
305M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
45.3M
            const unsigned char *_p = p;
30
609M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
580M
                size_t value = *(const size_t *) _p;
32
580M
                if (value & UCS1_ASCII_CHAR_MASK)
33
16.4M
                    return 255;
34
563M
                _p += SIZEOF_SIZE_T;
35
563M
            }
36
28.8M
            p = _p;
37
28.8M
            if (p == _end)
38
627k
                break;
39
28.8M
        }
40
287M
        if (*p++ & 0x80)
41
3.69M
            return 255;
42
287M
    }
43
29.6M
    return 127;
44
49.7M
}
unicodeobject.c:ucs1lib_find_max_char
Line
Count
Source
22
49.7M
{
23
49.7M
    const unsigned char *p = (const unsigned char *) begin;
24
49.7M
    const unsigned char *_end = (const unsigned char *)end;
25
26
334M
    while (p < _end) {
27
305M
        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
28
            /* Help register allocation */
29
45.3M
            const unsigned char *_p = p;
30
609M
            while (_p + SIZEOF_SIZE_T <= _end) {
31
580M
                size_t value = *(const size_t *) _p;
32
580M
                if (value & UCS1_ASCII_CHAR_MASK)
33
16.4M
                    return 255;
34
563M
                _p += SIZEOF_SIZE_T;
35
563M
            }
36
28.8M
            p = _p;
37
28.8M
            if (p == _end)
38
627k
                break;
39
28.8M
        }
40
287M
        if (*p++ & 0x80)
41
3.69M
            return 255;
42
287M
    }
43
29.6M
    return 127;
44
49.7M
}
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
72.1M
#define MASK_ASCII 0xFFFFFF80
51
47.9M
#define MASK_UCS1 0xFFFFFF00
52
24.1M
#define MASK_UCS2 0xFFFF0000
53
54
45.5M
#define MAX_CHAR_ASCII 0x7f
55
21.3M
#define MAX_CHAR_UCS1  0xff
56
31.8M
#define MAX_CHAR_UCS2  0xffff
57
18.9M
#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
45.5M
{
62
#if STRINGLIB_SIZEOF_CHAR == 2
63
26.5M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
26.5M
    const Py_UCS4 max_char_limit = MAX_CHAR_UCS2;
65
#elif STRINGLIB_SIZEOF_CHAR == 4
66
18.9M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
18.9M
    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
45.5M
    Py_UCS4 mask;
72
45.5M
    Py_ssize_t n = end - begin;
73
45.5M
    const STRINGLIB_CHAR *p = begin;
74
45.5M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
45.5M
    Py_UCS4 max_char;
76
77
45.5M
    max_char = MAX_CHAR_ASCII;
78
45.5M
    mask = MASK_ASCII;
79
2.19G
    while (p < unrolled_end) {
80
2.16G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
2.16G
        if (bits & mask) {
82
40.3M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
15.8M
                return max_char_limit;
85
15.8M
            }
86
24.4M
            if (mask == MASK_ASCII) {
87
19.9M
                max_char = MAX_CHAR_UCS1;
88
19.9M
                mask = MASK_UCS1;
89
19.9M
            }
90
4.51M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
4.51M
                assert(mask == MASK_UCS1);
93
4.51M
                max_char = MAX_CHAR_UCS2;
94
4.51M
                mask = MASK_UCS2;
95
4.51M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
24.4M
            continue;
98
40.3M
        }
99
2.12G
        p += 4;
100
2.12G
    }
101
91.0M
    while (p < end) {
102
62.1M
        if (p[0] & mask) {
103
2.91M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
763k
                return max_char_limit;
106
763k
            }
107
2.15M
            if (mask == MASK_ASCII) {
108
1.45M
                max_char = MAX_CHAR_UCS1;
109
1.45M
                mask = MASK_UCS1;
110
1.45M
            }
111
694k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
694k
                assert(mask == MASK_UCS1);
114
694k
                max_char = MAX_CHAR_UCS2;
115
694k
                mask = MASK_UCS2;
116
694k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
2.15M
            continue;
119
2.91M
        }
120
59.2M
        p++;
121
59.2M
    }
122
28.9M
    return max_char;
123
29.6M
}
unicodeobject.c:ucs4lib_find_max_char
Line
Count
Source
61
18.9M
{
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
18.9M
    const Py_UCS4 mask_limit = MASK_UCS2;
67
18.9M
    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
18.9M
    Py_UCS4 mask;
72
18.9M
    Py_ssize_t n = end - begin;
73
18.9M
    const STRINGLIB_CHAR *p = begin;
74
18.9M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
18.9M
    Py_UCS4 max_char;
76
77
18.9M
    max_char = MAX_CHAR_ASCII;
78
18.9M
    mask = MASK_ASCII;
79
697M
    while (p < unrolled_end) {
80
680M
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
680M
        if (bits & mask) {
82
11.5M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
1.54M
                return max_char_limit;
85
1.54M
            }
86
10.0M
            if (mask == MASK_ASCII) {
87
5.53M
                max_char = MAX_CHAR_UCS1;
88
5.53M
                mask = MASK_UCS1;
89
5.53M
            }
90
4.51M
            else {
91
                /* mask can't be MASK_UCS2 because of mask_limit above */
92
4.51M
                assert(mask == MASK_UCS1);
93
4.51M
                max_char = MAX_CHAR_UCS2;
94
4.51M
                mask = MASK_UCS2;
95
4.51M
            }
96
            /* We check the new mask on the same chars in the next iteration */
97
10.0M
            continue;
98
11.5M
        }
99
668M
        p += 4;
100
668M
    }
101
54.8M
    while (p < end) {
102
37.4M
        if (p[0] & mask) {
103
1.55M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
93.4k
                return max_char_limit;
106
93.4k
            }
107
1.46M
            if (mask == MASK_ASCII) {
108
767k
                max_char = MAX_CHAR_UCS1;
109
767k
                mask = MASK_UCS1;
110
767k
            }
111
694k
            else {
112
                /* mask can't be MASK_UCS2 because of mask_limit above */
113
694k
                assert(mask == MASK_UCS1);
114
694k
                max_char = MAX_CHAR_UCS2;
115
694k
                mask = MASK_UCS2;
116
694k
            }
117
            /* We check the new mask on the same chars in the next iteration */
118
1.46M
            continue;
119
1.55M
        }
120
35.9M
        p++;
121
35.9M
    }
122
17.3M
    return max_char;
123
17.4M
}
unicodeobject.c:ucs2lib_find_max_char
Line
Count
Source
61
26.5M
{
62
26.5M
#if STRINGLIB_SIZEOF_CHAR == 2
63
26.5M
    const Py_UCS4 mask_limit = MASK_UCS1;
64
26.5M
    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
26.5M
    Py_UCS4 mask;
72
26.5M
    Py_ssize_t n = end - begin;
73
26.5M
    const STRINGLIB_CHAR *p = begin;
74
26.5M
    const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);
75
26.5M
    Py_UCS4 max_char;
76
77
26.5M
    max_char = MAX_CHAR_ASCII;
78
26.5M
    mask = MASK_ASCII;
79
1.49G
    while (p < unrolled_end) {
80
1.48G
        STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];
81
1.48G
        if (bits & mask) {
82
28.7M
            if (mask == mask_limit) {
83
                /* Limit reached */
84
14.3M
                return max_char_limit;
85
14.3M
            }
86
14.4M
            if (mask == MASK_ASCII) {
87
14.4M
                max_char = MAX_CHAR_UCS1;
88
14.4M
                mask = MASK_UCS1;
89
14.4M
            }
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
14.4M
            continue;
98
28.7M
        }
99
1.45G
        p += 4;
100
1.45G
    }
101
36.2M
    while (p < end) {
102
24.7M
        if (p[0] & mask) {
103
1.35M
            if (mask == mask_limit) {
104
                /* Limit reached */
105
669k
                return max_char_limit;
106
669k
            }
107
689k
            if (mask == MASK_ASCII) {
108
689k
                max_char = MAX_CHAR_UCS1;
109
689k
                mask = MASK_UCS1;
110
689k
            }
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
689k
            continue;
119
1.35M
        }
120
23.3M
        p++;
121
23.3M
    }
122
11.5M
    return max_char;
123
12.2M
}
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