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authorZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
committerZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
commit5046dbb4a7eba5eccfd258f92f4735c9ffc8d069 (patch)
tree4470480d904b65cf14ca524f96f79eca818c3eaf /REORG.TODO/benchtests/bench-strncmp.c
parent199fc19d3aaaf57944ef036e15904febe877fc93 (diff)
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Prepare for radical source tree reorganization. zack/build-layout-experiment
All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).
Diffstat (limited to 'REORG.TODO/benchtests/bench-strncmp.c')
-rw-r--r--REORG.TODO/benchtests/bench-strncmp.c299
1 files changed, 299 insertions, 0 deletions
diff --git a/REORG.TODO/benchtests/bench-strncmp.c b/REORG.TODO/benchtests/bench-strncmp.c
new file mode 100644
index 0000000000..dddd009792
--- /dev/null
+++ b/REORG.TODO/benchtests/bench-strncmp.c
@@ -0,0 +1,299 @@
+/* Measure strncmp 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
+#ifdef WIDE
+# define TEST_NAME "wcsncmp"
+#else
+# define TEST_NAME "strncmp"
+#endif /* !WIDE */
+#include "bench-string.h"
+
+#ifdef WIDE
+# include <wchar.h>
+
+# define L(str) L##str
+# define STRNCMP wcsncmp
+# define SIMPLE_STRNCMP simple_wcsncmp
+# define STUPID_STRNCMP stupid_wcsncmp
+# define CHAR wchar_t
+# define CHARBYTES 4
+
+/* Wcsncmp uses signed semantics for comparison, not unsigned.
+   Avoid using substraction since possible overflow.  */
+int
+simple_wcsncmp (const CHAR *s1, const CHAR *s2, size_t n)
+{
+  wchar_t c1, c2;
+
+  while (n--)
+    {
+      c1 = *s1++;
+      c2 = *s2++;
+      if (c1 == L ('\0') || c1 != c2)
+	return c1 > c2 ? 1 : (c1 < c2 ? -1 : 0);
+    }
+  return 0;
+}
+
+int
+stupid_wcsncmp (const CHAR *s1, const CHAR *s2, size_t n)
+{
+  wchar_t c1, c2;
+  size_t ns1 = wcsnlen (s1, n) + 1, ns2 = wcsnlen (s2, n) + 1;
+
+  n = ns1 < n ? ns1 : n;
+  n = ns2 < n ? ns2 : n;
+
+  while (n--)
+    {
+      c1 = *s1++;
+      c2 = *s2++;
+      if (c1 != c2)
+	return c1 > c2 ? 1 : -1;
+    }
+  return 0;
+}
+
+#else
+# define L(str) str
+# define STRNCMP strncmp
+# define SIMPLE_STRNCMP simple_strncmp
+# define STUPID_STRNCMP stupid_strncmp
+# define CHAR char
+# define CHARBYTES 1
+
+/* Strncmp uses unsigned semantics for comparison.  */
+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;
+}
+
+#endif /* !WIDE */
+
+typedef int (*proto_t) (const CHAR *, const CHAR *, size_t);
+
+IMPL (STUPID_STRNCMP, 0)
+IMPL (SIMPLE_STRNCMP, 0)
+IMPL (STRNCMP, 1)
+
+
+static void
+do_one_test (impl_t *impl, const CHAR *s1, const CHAR *s2, size_t n,
+	     int exp_result)
+{
+  size_t i, iters = INNER_LOOP_ITERS;
+  timing_t start, stop, cur;
+
+  TIMING_NOW (start);
+  for (i = 0; i < iters; ++i)
+    {
+      CALL (impl, s1, s2, n);
+    }
+  TIMING_NOW (stop);
+
+  TIMING_DIFF (cur, start, stop);
+
+  TIMING_PRINT_MEAN ((double) cur, (double) iters);
+}
+
+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);
+      printf ("Length %4zd/%4zd:", len, n);
+
+      FOR_EACH_IMPL (impl, 0)
+	do_one_test (impl, s1, s2, n, 0);
+
+      putchar ('\n');
+
+      return;
+    }
+
+  align1 &= 15;
+  align2 &= 15;
+  align_n = (page_size - n * CHARBYTES) & 15;
+
+  s1 = (CHAR *) (buf1 + page_size - n * CHARBYTES);
+  s2 = (CHAR *) (buf2 + page_size - n * CHARBYTES);
+
+  if (align1 < align_n)
+    s1 = (CHAR *) ((char *) s1 - (align_n - align1));
+
+  if (align2 < align_n)
+    s2 = (CHAR *) ((char *) 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;
+    }
+
+  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);
+
+  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 &= 63;
+  if (align1 + (n + 1) * CHARBYTES >= page_size)
+    return;
+
+  align2 &= 7;
+  if (align2 + (n + 1) * CHARBYTES >= page_size)
+    return;
+
+  s1 = (CHAR *) (buf1 + align1);
+  s2 = (CHAR *) (buf2 + align2);
+
+  for (i = 0; i < n; i++)
+    s1[i] = s2[i] = 1 + (23 << ((CHARBYTES - 1) * 8)) * 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;
+
+  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);
+
+  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 <support/test-driver.c>