glibc/benchtests/bench-bzero.c

/* Measure bzero functions.
   Copyright (C) 2022 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
   <https://www.gnu.org/licenses/>.  */

#define TEST_MAIN
#ifdef DO_MEMSET
# define TEST_NAME "memset"
#else
# define TEST_NAME "bzero"
#endif
#define MIN_PAGE_SIZE 131072
#include "bench-string.h"

#include "json-lib.h"

#ifdef DO_MEMSET
void *generic_memset (void *, int, size_t);

typedef void *(*proto_t) (void *, int, size_t);

IMPL (memset, 1)
IMPL (generic_memset, 0)

#else
static void
memset_zero (void * s, size_t len)
{
  memset (s, '\0', len);
}

typedef void (*proto_t) (void *, size_t);

IMPL (bzero, 1)
IMPL (memset_zero, 0)
#endif

static void
do_one_test (json_ctx_t *json_ctx, impl_t *impl, CHAR *s, size_t n)
{
  size_t i, iters = INNER_LOOP_ITERS_LARGE;
  timing_t start, stop, cur;

  TIMING_NOW (start);
  for (i = 0; i < iters; ++i)
    {
#ifdef DO_MEMSET
      CALL (impl, s, 0, n);
#else
      CALL (impl, s, n);
#endif
    }
  TIMING_NOW (stop);

  TIMING_DIFF (cur, start, stop);

  json_element_double (json_ctx, (double) cur / (double) iters);
}

static void
do_test (json_ctx_t *json_ctx, size_t align, size_t len)
{
  align &= 4095;
  if ((align + len) * sizeof (CHAR) > page_size)
    return;

  json_element_object_begin (json_ctx);
  json_attr_uint (json_ctx, "length", len);
  json_attr_uint (json_ctx, "alignment", align);
  json_array_begin (json_ctx, "timings");

  FOR_EACH_IMPL (impl, 0)
    {
      do_one_test (json_ctx, impl, (CHAR *) (buf1) + align, len);
    }

  json_array_end (json_ctx);
  json_element_object_end (json_ctx);
}

int
test_main (void)
{
  json_ctx_t json_ctx;
  size_t i;

  test_init ();
  alloc_bufs ();
  json_init (&json_ctx, 0, stdout);

  json_document_begin (&json_ctx);
  json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);

  json_attr_object_begin (&json_ctx, "functions");
  json_attr_object_begin (&json_ctx, TEST_NAME);
  json_attr_string (&json_ctx, "bench-variant", "default");

  json_array_begin (&json_ctx, "ifuncs");
  FOR_EACH_IMPL (impl, 0)
    json_element_string (&json_ctx, impl->name);
  json_array_end (&json_ctx);

  json_array_begin (&json_ctx, "results");

  for (i = 0; i < 18; ++i)
    do_test (&json_ctx, 0, 1 << i);
  for (i = 0; i < 64; ++i)
    {
      do_test (&json_ctx, i, i);
      do_test (&json_ctx, 4096 - i, i);
      do_test (&json_ctx, 4095, i);
      if (i & (i - 1))
	do_test (&json_ctx, 0, i);
    }
  for (i = 32; i < 1024; i+=32)
    {
      do_test (&json_ctx, 0, i);
      do_test (&json_ctx, i, i);
    }
  do_test (&json_ctx, 1, 14);
  do_test (&json_ctx, 3, 1024);
  do_test (&json_ctx, 4, 64);
  do_test (&json_ctx, 2, 25);

  for (i = 33; i <= 256; i += 4)
    {
      do_test (&json_ctx, 0, 32 * i);
      do_test (&json_ctx, i, 32 * i);
    }

  json_array_end (&json_ctx);
  json_attr_object_end (&json_ctx);
  json_attr_object_end (&json_ctx);
  json_document_end (&json_ctx);

  return ret;
}

#include <support/test-driver.c>

#ifdef DO_MEMSET
# define libc_hidden_builtin_def(X)
# define libc_hidden_def(X)
# define libc_hidden_weak(X)
# define weak_alias(X,Y)
# undef MEMSET
# define MEMSET generic_memset
# include <string/memset.c>
#endif