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-rw-r--r--benchtests/bench-strncmp.c249
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"