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Diffstat (limited to 'benchtests/bench-strncmp.c')
| -rw-r--r-- | benchtests/bench-strncmp.c | 249 |
1 files changed, 249 insertions, 0 deletions
diff --git a/benchtests/bench-strncmp.c b/benchtests/bench-strncmp.c new file mode 100644 index 0000000000..b3af0f98e3 --- /dev/null +++ b/benchtests/bench-strncmp.c @@ -0,0 +1,249 @@ +/* Measure strncmp 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 "strncmp" +#include "bench-string.h" + +typedef int (*proto_t) (const char *, const char *, size_t); +int simple_strncmp (const char *, const char *, size_t); +int stupid_strncmp (const char *, const char *, size_t); + +IMPL (stupid_strncmp, 0) +IMPL (simple_strncmp, 0) +IMPL (strncmp, 1) + +int +simple_strncmp (const char *s1, const char *s2, size_t n) +{ + int ret = 0; + + while (n-- && (ret = *(unsigned char *) s1 - * (unsigned char *) s2++) == 0 + && *s1++); + return ret; +} + +int +stupid_strncmp (const char *s1, const char *s2, size_t n) +{ + size_t ns1 = strnlen (s1, n) + 1, ns2 = strnlen (s2, n) + 1; + int ret = 0; + + n = ns1 < n ? ns1 : n; + n = ns2 < n ? ns2 : n; + while (n-- && (ret = *(unsigned char *) s1++ - * (unsigned char *) s2++) == 0); + return ret; +} + +static void +do_one_test (impl_t *impl, const char *s1, const char *s2, size_t n, + int exp_result) +{ + 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, s1, s2, n); + HP_TIMING_NOW (stop); + HP_TIMING_BEST (best_time, start, stop); + } + + printf ("\t%zd", (size_t) best_time); + } +} + +static void +do_test_limit (size_t align1, size_t align2, size_t len, size_t n, int max_char, + int exp_result) +{ + size_t i, align_n; + char *s1, *s2; + + if (n == 0) + { + s1 = (char*)(buf1 + page_size); + s2 = (char*)(buf2 + page_size); + if (HP_TIMING_AVAIL) + printf ("Length %4zd/%4zd:", len, n); + + FOR_EACH_IMPL (impl, 0) + do_one_test (impl, s1, s2, n, 0); + + if (HP_TIMING_AVAIL) + putchar ('\n'); + + return; + } + + align1 &= 15; + align2 &= 15; + align_n = (page_size - n) & 15; + + s1 = (char*)(buf1 + page_size - n); + s2 = (char*)(buf2 + page_size - n); + + if (align1 < align_n) + s1 -= (align_n - align1); + + if (align2 < align_n) + s2 -= (align_n - align2); + + for (i = 0; i < n; i++) + s1[i] = s2[i] = 1 + 23 * i % max_char; + + if (len < n) + { + s1[len] = 0; + s2[len] = 0; + if (exp_result < 0) + s2[len] = 32; + else if (exp_result > 0) + s1[len] = 64; + } + + if (HP_TIMING_AVAIL) + printf ("Length %4zd/%4zd, alignment %2zd/%2zd:", len, n, align1, align2); + + FOR_EACH_IMPL (impl, 0) + do_one_test (impl, s1, s2, n, exp_result); + + if (HP_TIMING_AVAIL) + putchar ('\n'); +} + +static void +do_test (size_t align1, size_t align2, size_t len, size_t n, int max_char, + int exp_result) +{ + size_t i; + char *s1, *s2; + + if (n == 0) + return; + + align1 &= 7; + if (align1 + n + 1 >= page_size) + return; + + align2 &= 7; + if (align2 + n + 1 >= page_size) + return; + + s1 = (char*)(buf1 + align1); + s2 = (char*)(buf2 + align2); + + for (i = 0; i < n; i++) + s1[i] = s2[i] = 1 + 23 * i % max_char; + + s1[n] = 24 + exp_result; + s2[n] = 23; + s1[len] = 0; + s2[len] = 0; + if (exp_result < 0) + s2[len] = 32; + else if (exp_result > 0) + s1[len] = 64; + if (len >= n) + s2[n - 1] -= exp_result; + + if (HP_TIMING_AVAIL) + printf ("Length %4zd/%4zd, alignment %2zd/%2zd:", len, n, align1, align2); + + FOR_EACH_IMPL (impl, 0) + do_one_test (impl, (char*)s1, (char*)s2, n, exp_result); + + if (HP_TIMING_AVAIL) + putchar ('\n'); +} + +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 < 16; ++i) + { + do_test (0, 0, 8, i, 127, 0); + do_test (0, 0, 8, i, 127, -1); + do_test (0, 0, 8, i, 127, 1); + do_test (i, i, 8, i, 127, 0); + do_test (i, i, 8, i, 127, 1); + do_test (i, i, 8, i, 127, -1); + do_test (i, 2 * i, 8, i, 127, 0); + do_test (2 * i, i, 8, i, 127, 1); + do_test (i, 3 * i, 8, i, 127, -1); + do_test (0, 0, 8, i, 255, 0); + do_test (0, 0, 8, i, 255, -1); + do_test (0, 0, 8, i, 255, 1); + do_test (i, i, 8, i, 255, 0); + do_test (i, i, 8, i, 255, 1); + do_test (i, i, 8, i, 255, -1); + do_test (i, 2 * i, 8, i, 255, 0); + do_test (2 * i, i, 8, i, 255, 1); + do_test (i, 3 * i, 8, i, 255, -1); + } + + for (i = 1; i < 8; ++i) + { + do_test (0, 0, 8 << i, 16 << i, 127, 0); + do_test (0, 0, 8 << i, 16 << i, 127, 1); + do_test (0, 0, 8 << i, 16 << i, 127, -1); + do_test (0, 0, 8 << i, 16 << i, 255, 0); + do_test (0, 0, 8 << i, 16 << i, 255, 1); + do_test (0, 0, 8 << i, 16 << i, 255, -1); + do_test (8 - i, 2 * i, 8 << i, 16 << i, 127, 0); + do_test (8 - i, 2 * i, 8 << i, 16 << i, 127, 1); + do_test (2 * i, i, 8 << i, 16 << i, 255, 0); + do_test (2 * i, i, 8 << i, 16 << i, 255, 1); + } + + do_test_limit (0, 0, 0, 0, 127, 0); + do_test_limit (4, 0, 21, 20, 127, 0); + do_test_limit (0, 4, 21, 20, 127, 0); + do_test_limit (8, 0, 25, 24, 127, 0); + do_test_limit (0, 8, 25, 24, 127, 0); + + for (i = 0; i < 8; ++i) + { + do_test_limit (0, 0, 17 - i, 16 - i, 127, 0); + do_test_limit (0, 0, 17 - i, 16 - i, 255, 0); + do_test_limit (0, 0, 15 - i, 16 - i, 127, 0); + do_test_limit (0, 0, 15 - i, 16 - i, 127, 1); + do_test_limit (0, 0, 15 - i, 16 - i, 127, -1); + do_test_limit (0, 0, 15 - i, 16 - i, 255, 0); + do_test_limit (0, 0, 15 - i, 16 - i, 255, 1); + do_test_limit (0, 0, 15 - i, 16 - i, 255, -1); + } + + return ret; +} + +#include "../test-skeleton.c" |