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-rw-r--r--REORG.TODO/benchtests/bench-memmem.c164
1 files changed, 164 insertions, 0 deletions
diff --git a/REORG.TODO/benchtests/bench-memmem.c b/REORG.TODO/benchtests/bench-memmem.c
new file mode 100644
index 0000000000..3005f588bd
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+++ b/REORG.TODO/benchtests/bench-memmem.c
@@ -0,0 +1,164 @@
+/* Measure memmem functions.
+   Copyright (C) 2013-2017 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 (__glibc_unlikely (haystack_len < needle_len))
+    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)
+{
+  size_t i, iters = INNER_LOOP_ITERS;
+  timing_t start, stop, cur;
+
+  TIMING_NOW (start);
+  for (i = 0; i < iters; ++i)
+    {
+      CALL (impl, haystack, haystack_len, needle, needle_len);
+    }
+  TIMING_NOW (stop);
+
+  TIMING_DIFF (cur, start, stop);
+
+  TIMING_PRINT_MEAN ((double) cur, (double) iters);
+}
+
+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);
+
+  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);
+
+  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;
+	}
+
+      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);
+
+      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 <support/test-driver.c>