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Diffstat (limited to 'benchtests/bench-memmem.c')
| -rw-r--r-- | benchtests/bench-memmem.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/benchtests/bench-memmem.c b/benchtests/bench-memmem.c new file mode 100644 index 0000000..ca758a8 --- /dev/null +++ b/benchtests/bench-memmem.c @@ -0,0 +1,172 @@ +/* Measure memmem functions. + Copyright (C) 2013 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#define TEST_MAIN +#define TEST_NAME "memmem" +#define BUF1PAGES 20 +#define ITERATIONS 500 +#include "bench-string.h" + +typedef char *(*proto_t) (const void *, size_t, const void *, size_t); +void *simple_memmem (const void *, size_t, const void *, size_t); + +IMPL (simple_memmem, 0) +IMPL (memmem, 1) + +void * +simple_memmem (const void *haystack, size_t haystack_len, const void *needle, + size_t needle_len) +{ + const char *begin; + const char *const last_possible + = (const char *) haystack + haystack_len - needle_len; + + if (needle_len == 0) + /* The first occurrence of the empty string is deemed to occur at + the beginning of the string. */ + return (void *) haystack; + + /* Sanity check, otherwise the loop might search through the whole + memory. */ + if (__builtin_expect (haystack_len < needle_len, 0)) + return NULL; + + for (begin = (const char *) haystack; begin <= last_possible; ++begin) + if (begin[0] == ((const char *) needle)[0] && + !memcmp ((const void *) &begin[1], + (const void *) ((const char *) needle + 1), + needle_len - 1)) + return (void *) begin; + + return NULL; +} + +static void +do_one_test (impl_t *impl, const void *haystack, size_t haystack_len, + const void *needle, size_t needle_len, const void *expected) +{ + if (HP_TIMING_AVAIL) + { + hp_timing_t start __attribute ((unused)); + hp_timing_t stop __attribute ((unused)); + hp_timing_t best_time = ~ (hp_timing_t) 0; + size_t i; + + for (i = 0; i < 32; ++i) + { + HP_TIMING_NOW (start); + CALL (impl, haystack, haystack_len, needle, needle_len); + HP_TIMING_NOW (stop); + HP_TIMING_BEST (best_time, start, stop); + } + + printf ("\t%zd", (size_t) best_time); + } +} + +static void +do_test (const char *str, size_t len, size_t idx) +{ + char tmpbuf[len]; + + memcpy (tmpbuf, buf1 + idx, len); + memcpy (buf1 + idx, str, len); + + if (HP_TIMING_AVAIL) + printf ("String %s, offset %zd:", str, idx); + + FOR_EACH_IMPL (impl, 0) + do_one_test (impl, buf1, BUF1PAGES * page_size, str, len, buf1 + idx); + + memcpy (buf1 + idx, tmpbuf, len); + + if (HP_TIMING_AVAIL) + putchar ('\n'); +} + +static void +do_random_tests (void) +{ + for (size_t n = 0; n < ITERATIONS; ++n) + { + char tmpbuf[32]; + + size_t shift = random () % 11; + size_t rel = random () % ((2 << (shift + 1)) * 64); + size_t idx = MIN ((2 << shift) * 64 + rel, BUF1PAGES * page_size - 2); + size_t len = random () % (sizeof (tmpbuf) - 1) + 1; + len = MIN (len, BUF1PAGES * page_size - idx - 1); + memcpy (tmpbuf, buf1 + idx, len); + for (size_t i = random () % len / 2 + 1; i > 0; --i) + { + size_t off = random () % len; + char ch = '0' + random () % 10; + + buf1[idx + off] = ch; + } + + if (HP_TIMING_AVAIL) + printf ("String %.*s, offset %zd:", (int) len, buf1 + idx, idx); + + FOR_EACH_IMPL (impl, 0) + do_one_test (impl, buf1, BUF1PAGES * page_size, buf1 + idx, len, + buf1 + idx); + + if (HP_TIMING_AVAIL) + putchar ('\n'); + + memcpy (buf1 + idx, tmpbuf, len); + } +} + +static const char *const strs[] = + { + "00000", "00112233", "0123456789", "0000111100001111", + "00000111110000022222", "012345678901234567890", + "abc0", "aaaa0", "abcabc0" + }; + + +int +test_main (void) +{ + size_t i; + + test_init (); + + printf ("%23s", ""); + FOR_EACH_IMPL (impl, 0) + printf ("\t%s", impl->name); + putchar ('\n'); + + for (i = 0; i < BUF1PAGES * page_size; ++i) + buf1[i] = 60 + random () % 32; + + for (i = 0; i < sizeof (strs) / sizeof (strs[0]); ++i) + for (size_t j = 0; j < 120; j += 7) + { + size_t len = strlen (strs[i]); + + do_test (strs[i], len, j); + } + + do_random_tests (); + return ret; +} + +#include "../test-skeleton.c" |