]>
Commit | Line | Data |
---|---|---|
55364e1f | 1 | /* Test the heapsort implementation behind qsort. |
dff8da6b | 2 | Copyright (C) 2023-2024 Free Software Foundation, Inc. |
55364e1f FW |
3 | This file is part of the GNU C Library. |
4 | ||
5 | The GNU C Library is free software; you can redistribute it and/or | |
6 | modify it under the terms of the GNU Lesser General Public | |
7 | License as published by the Free Software Foundation; either | |
8 | version 2.1 of the License, or (at your option) any later version. | |
9 | ||
10 | The GNU C Library is distributed in the hope that it will be useful, | |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
13 | Lesser General Public License for more details. | |
14 | ||
15 | You should have received a copy of the GNU Lesser General Public | |
16 | License along with the GNU C Library; if not, see | |
17 | <http://www.gnu.org/licenses/>. */ | |
18 | ||
19 | #include "qsort.c" | |
20 | ||
21 | #include <stdio.h> | |
22 | #include <support/check.h> | |
23 | #include <support/support.h> | |
24 | ||
25 | static int | |
26 | cmp (const void *a1, const void *b1, void *closure) | |
27 | { | |
28 | const signed char *a = a1; | |
29 | const signed char *b = b1; | |
30 | return *a - *b; | |
31 | } | |
32 | ||
33 | /* Wrapper around heapsort_r that set ups the required variables. */ | |
34 | static void | |
35 | heapsort_wrapper (void *const pbase, size_t total_elems, size_t size, | |
36 | __compar_d_fn_t cmp, void *arg) | |
37 | { | |
38 | char *base_ptr = (char *) pbase; | |
39 | char *lo = base_ptr; | |
40 | char *hi = &lo[size * (total_elems - 1)]; | |
41 | ||
42 | if (total_elems <= 1) | |
43 | /* Avoid lossage with unsigned arithmetic below. */ | |
44 | return; | |
45 | ||
46 | enum swap_type_t swap_type; | |
47 | if (is_aligned (pbase, size, 8)) | |
48 | swap_type = SWAP_WORDS_64; | |
49 | else if (is_aligned (pbase, size, 4)) | |
50 | swap_type = SWAP_WORDS_32; | |
51 | else | |
52 | swap_type = SWAP_BYTES; | |
53 | heapsort_r (lo, hi, size, swap_type, cmp, arg); | |
54 | } | |
55 | ||
56 | static void | |
57 | check_one_sort (signed char *array, int length) | |
58 | { | |
59 | signed char *copy = xmalloc (length); | |
60 | memcpy (copy, array, length); | |
61 | heapsort_wrapper (copy, length, 1, cmp, NULL); | |
62 | ||
63 | /* Verify that the result is sorted. */ | |
64 | for (int i = 1; i < length; ++i) | |
65 | if (copy[i] < copy[i - 1]) | |
66 | { | |
67 | support_record_failure (); | |
68 | printf ("error: sorting failure for length %d at offset %d\n", | |
69 | length, i - 1); | |
70 | printf ("input:"); | |
71 | for (int i = 0; i < length; ++i) | |
72 | printf (" %d", array[i]); | |
73 | printf ("\noutput:"); | |
74 | for (int i = 0; i < length; ++i) | |
75 | printf (" %d", copy[i]); | |
76 | putchar ('\n'); | |
77 | break; | |
78 | } | |
79 | ||
80 | /* Verify that no elements went away or were added. */ | |
81 | { | |
82 | int expected_counts[256]; | |
83 | for (int i = 0; i < length; ++i) | |
84 | ++expected_counts[array[i] & 0xff]; | |
85 | int actual_counts[256]; | |
86 | for (int i = 0; i < length; ++i) | |
87 | ++actual_counts[copy[i] & 0xff]; | |
88 | for (int i = 0; i < 256; ++i) | |
89 | TEST_COMPARE (expected_counts[i], expected_counts[i]); | |
90 | } | |
91 | ||
92 | free (copy); | |
93 | } | |
94 | ||
95 | /* Enumerate all possible combinations of LENGTH elements. */ | |
96 | static void | |
97 | check_combinations (int length, signed char *start, int offset) | |
98 | { | |
99 | if (offset == length) | |
100 | check_one_sort (start, length); | |
101 | else | |
102 | for (int i = 0; i < length; ++i) | |
103 | { | |
104 | start[offset] = i; | |
105 | check_combinations(length, start, offset + 1); | |
106 | } | |
107 | } | |
108 | ||
109 | static int | |
110 | do_test (void) | |
111 | { | |
112 | /* A random permutation of 20 values. */ | |
113 | check_one_sort ((signed char[20]) {5, 12, 16, 10, 14, 11, 9, 13, 8, 15, | |
114 | 0, 17, 3, 7, 1, 18, 2, 19, 4, 6}, 20); | |
115 | ||
116 | ||
117 | /* A permutation that appeared during adversarial testing for the | |
118 | quicksort pass. */ | |
119 | check_one_sort ((signed char[16]) {15, 3, 4, 2, 1, 0, 8, 7, 6, 5, 14, | |
120 | 13, 12, 11, 10, 9}, 16); | |
121 | ||
122 | /* Array lengths 2 and less are not handled by heapsort_r and | |
123 | deferred to insertion sort. */ | |
124 | for (int i = 3; i <= 8; ++i) | |
125 | { | |
126 | signed char *buf = xmalloc (i); | |
127 | check_combinations (i, buf, 0); | |
128 | free (buf); | |
129 | } | |
130 | ||
131 | return 0; | |
132 | } | |
133 | ||
134 | #include <support/test-driver.c> |