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-rw-r--r--libc/benchtests/bench-strcmp.c247
1 files changed, 247 insertions, 0 deletions
diff --git a/libc/benchtests/bench-strcmp.c b/libc/benchtests/bench-strcmp.c
new file mode 100644
index 000000000..63a3cd499
--- /dev/null
+++ b/libc/benchtests/bench-strcmp.c
@@ -0,0 +1,247 @@
+/* Measure strcmp and wcscmp 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
+#ifdef WIDE
+# define TEST_NAME "wcscmp"
+#else
+# define TEST_NAME "strcmp"
+#endif
+#include "bench-string.h"
+
+#ifdef WIDE
+# include <wchar.h>
+
+# define L(str) L##str
+# define STRCMP wcscmp
+# define STRCPY wcscpy
+# define STRLEN wcslen
+# define MEMCPY wmemcpy
+# define SIMPLE_STRCMP simple_wcscmp
+# define STUPID_STRCMP stupid_wcscmp
+# define CHAR wchar_t
+# define UCHAR wchar_t
+# define CHARBYTES 4
+# define CHARBYTESLOG 2
+# define CHARALIGN __alignof__ (CHAR)
+# define MIDCHAR 0x7fffffff
+# define LARGECHAR 0xfffffffe
+# define CHAR__MAX WCHAR_MAX
+# define CHAR__MIN WCHAR_MIN
+
+/* Wcscmp uses signed semantics for comparison, not unsigned */
+/* Avoid using substraction since possible overflow */
+
+int
+simple_wcscmp (const wchar_t *s1, const wchar_t *s2)
+{
+ wchar_t c1, c2;
+ do
+ {
+ c1 = *s1++;
+ c2 = *s2++;
+ if (c2 == L'\0')
+ return c1 - c2;
+ }
+ while (c1 == c2);
+
+ return c1 < c2 ? -1 : 1;
+}
+
+int
+stupid_wcscmp (const wchar_t *s1, const wchar_t *s2)
+{
+ size_t ns1 = wcslen (s1) + 1;
+ size_t ns2 = wcslen (s2) + 1;
+ size_t n = ns1 < ns2 ? ns1 : ns2;
+ int ret = 0;
+
+ wchar_t c1, c2;
+
+ while (n--) {
+ c1 = *s1++;
+ c2 = *s2++;
+ if ((ret = c1 < c2 ? -1 : c1 == c2 ? 0 : 1) != 0)
+ break;
+ }
+ return ret;
+}
+
+#else
+# include <limits.h>
+
+# define L(str) str
+# define STRCMP strcmp
+# define STRCPY strcpy
+# define STRLEN strlen
+# define MEMCPY memcpy
+# define SIMPLE_STRCMP simple_strcmp
+# define STUPID_STRCMP stupid_strcmp
+# define CHAR char
+# define UCHAR unsigned char
+# define CHARBYTES 1
+# define CHARBYTESLOG 0
+# define CHARALIGN 1
+# define MIDCHAR 0x7f
+# define LARGECHAR 0xfe
+# define CHAR__MAX CHAR_MAX
+# define CHAR__MIN CHAR_MIN
+
+/* Strcmp uses unsigned semantics for comparison. */
+int
+simple_strcmp (const char *s1, const char *s2)
+{
+ int ret;
+
+ while ((ret = *(unsigned char *) s1 - *(unsigned char*) s2++) == 0 && *s1++);
+ return ret;
+}
+
+int
+stupid_strcmp (const char *s1, const char *s2)
+{
+ size_t ns1 = strlen (s1) + 1;
+ size_t ns2 = strlen (s2) + 1;
+ size_t n = ns1 < ns2 ? ns1 : ns2;
+ int ret = 0;
+
+ while (n--)
+ if ((ret = *(unsigned char *) s1++ - *(unsigned char *) s2++) != 0)
+ break;
+ return ret;
+}
+#endif
+
+typedef int (*proto_t) (const CHAR *, const CHAR *);
+
+IMPL (STUPID_STRCMP, 1)
+IMPL (SIMPLE_STRCMP, 1)
+IMPL (STRCMP, 1)
+
+static void
+do_one_test (impl_t *impl,
+ const CHAR *s1, const CHAR *s2,
+ 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);
+ HP_TIMING_NOW (stop);
+ HP_TIMING_BEST (best_time, start, stop);
+ }
+
+ printf ("\t%zd", (size_t) best_time);
+ }
+}
+
+static void
+do_test (size_t align1, size_t align2, size_t len, int max_char,
+ int exp_result)
+{
+ size_t i;
+
+ CHAR *s1, *s2;
+
+ if (len == 0)
+ return;
+
+ align1 &= 63;
+ if (align1 + (len + 1) * CHARBYTES >= page_size)
+ return;
+
+ align2 &= 63;
+ if (align2 + (len + 1) * CHARBYTES >= page_size)
+ return;
+
+ /* Put them close to the end of page. */
+ i = align1 + CHARBYTES * (len + 2);
+ s1 = (CHAR *) (buf1 + ((page_size - i) / 16 * 16) + align1);
+ i = align2 + CHARBYTES * (len + 2);
+ s2 = (CHAR *) (buf2 + ((page_size - i) / 16 * 16) + align2);
+
+ for (i = 0; i < len; i++)
+ s1[i] = s2[i] = 1 + (23 << ((CHARBYTES - 1) * 8)) * i % max_char;
+
+ s1[len] = s2[len] = 0;
+ s1[len + 1] = 23;
+ s2[len + 1] = 24 + exp_result;
+ s2[len - 1] -= exp_result;
+
+ if (HP_TIMING_AVAIL)
+ printf ("Length %4zd, alignment %2zd/%2zd:", len, align1, align2);
+
+ FOR_EACH_IMPL (impl, 0)
+ do_one_test (impl, s1, s2, 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 = 1; i < 32; ++i)
+ {
+ do_test (CHARBYTES * i, CHARBYTES * i, i, MIDCHAR, 0);
+ do_test (CHARBYTES * i, CHARBYTES * i, i, MIDCHAR, 1);
+ do_test (CHARBYTES * i, CHARBYTES * i, i, MIDCHAR, -1);
+ }
+
+ for (i = 1; i < 10 + CHARBYTESLOG; ++i)
+ {
+ do_test (0, 0, 2 << i, MIDCHAR, 0);
+ do_test (0, 0, 2 << i, LARGECHAR, 0);
+ do_test (0, 0, 2 << i, MIDCHAR, 1);
+ do_test (0, 0, 2 << i, LARGECHAR, 1);
+ do_test (0, 0, 2 << i, MIDCHAR, -1);
+ do_test (0, 0, 2 << i, LARGECHAR, -1);
+ do_test (0, CHARBYTES * i, 2 << i, MIDCHAR, 1);
+ do_test (CHARBYTES * i, CHARBYTES * (i + 1), 2 << i, LARGECHAR, 1);
+ }
+
+ for (i = 1; i < 8; ++i)
+ {
+ do_test (CHARBYTES * i, 2 * CHARBYTES * i, 8 << i, MIDCHAR, 0);
+ do_test (2 * CHARBYTES * i, CHARBYTES * i, 8 << i, LARGECHAR, 0);
+ do_test (CHARBYTES * i, 2 * CHARBYTES * i, 8 << i, MIDCHAR, 1);
+ do_test (2 * CHARBYTES * i, CHARBYTES * i, 8 << i, LARGECHAR, 1);
+ do_test (CHARBYTES * i, 2 * CHARBYTES * i, 8 << i, MIDCHAR, -1);
+ do_test (2 * CHARBYTES * i, CHARBYTES * i, 8 << i, LARGECHAR, -1);
+ }
+
+ return ret;
+}
+
+#include "../test-skeleton.c"
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