/* Skeleton for benchmark programs.

   Copyright (C) 2013-2018 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/>.  */

#include <string.h>

#include <stdint.h>

#include <stdbool.h>

#include <stdio.h>

#include <time.h>

#include <inttypes.h>

#include "bench-timing.h"

#include "json-lib.h"

#include "bench-util.h"

#include "bench-util.c"

#define TIMESPEC_AFTER(a, b) \

  (((a).tv_sec == (b).tv_sec) ?						      \

     ((a).tv_nsec > (b).tv_nsec) :					      \

	((a).tv_sec > (b).tv_sec))

int

main (int argc, char **argv)

{

  unsigned long i, k;

  struct timespec runtime;

  timing_t start, end;

  bool detailed = false;

  json_ctx_t json_ctx;

  if (argc == 2 && !strcmp (argv[1], "-d"))

    detailed = true;

  bench_start ();

  memset (&runtime, 0, sizeof (runtime));

  unsigned long iters, res;

#ifdef BENCH_INIT

  BENCH_INIT ();

#endif

  TIMING_INIT (res);

  iters = 1000 * res;

  json_init (&json_ctx, 2, stdout);

  /* Begin function.  */

  json_attr_object_begin (&json_ctx, FUNCNAME);

  for (int v = 0; v < NUM_VARIANTS; v++)

    {

      /* Run for approximately DURATION seconds.  */

      clock_gettime (CLOCK_MONOTONIC_RAW, &runtime);

      runtime.tv_sec += DURATION;

      bool is_bench = strncmp (VARIANT (v), "workload-", 9) == 0;

      double d_total_i = 0;

      timing_t total = 0, max = 0, min = 0x7fffffffffffffff;

      timing_t throughput = 0, latency = 0;

      int64_t c = 0;

      uint64_t cur;

      BENCH_VARS;

      while (1)

	{

	  if (is_bench)

	    {

	      /* Benchmark a real trace of calls - all samples are iterated

		 over once before repeating.  This models actual use more

		 accurately than repeating the same sample many times.  */

	      TIMING_NOW (start);

	      for (k = 0; k < iters; k++)

		for (i = 0; i < NUM_SAMPLES (v); i++)

		  BENCH_FUNC (v, i);

	      TIMING_NOW (end);

	      TIMING_DIFF (cur, start, end);

	      TIMING_ACCUM (throughput, cur);

	      TIMING_NOW (start);

	      for (k = 0; k < iters; k++)

		for (i = 0; i < NUM_SAMPLES (v); i++)

		  BENCH_FUNC_LAT (v, i);

	      TIMING_NOW (end);

	      TIMING_DIFF (cur, start, end);

	      TIMING_ACCUM (latency, cur);

	      d_total_i += iters * NUM_SAMPLES (v);

	    }

	  else

	    for (i = 0; i < NUM_SAMPLES (v); i++)

	      {

		TIMING_NOW (start);

		for (k = 0; k < iters; k++)

		  BENCH_FUNC (v, i);

		TIMING_NOW (end);

		TIMING_DIFF (cur, start, end);

		if (cur > max)

		  max = cur;

		if (cur < min)

		  min = cur;

		TIMING_ACCUM (total, cur);

		/* Accumulate timings for the value.  In the end we will divide

		   by the total iterations.  */

		RESULT_ACCUM (cur, v, i, c * iters, (c + 1) * iters);

		d_total_i += iters;

	      }

	  c++;

	  struct timespec curtime;

	  memset (&curtime, 0, sizeof (curtime));

	  clock_gettime (CLOCK_MONOTONIC_RAW, &curtime);

	  if (TIMESPEC_AFTER (curtime, runtime))

	    goto done;

	}

      double d_total_s;

      double d_iters;

    done:

      d_total_s = total;

      d_iters = iters;

      /* Begin variant.  */

      json_attr_object_begin (&json_ctx, VARIANT (v));

      if (is_bench)

	{

	  json_attr_double (&json_ctx, "reciprocal-throughput",

			    throughput / d_total_i);

	  json_attr_double (&json_ctx, "latency", latency / d_total_i);

	  json_attr_double (&json_ctx, "max-throughput",

			    d_total_i / throughput * 1000000000.0);

	  json_attr_double (&json_ctx, "min-throughput",

			    d_total_i / latency * 1000000000.0);

	}

      else

	{

	  json_attr_double (&json_ctx, "duration", d_total_s);

	  json_attr_double (&json_ctx, "iterations", d_total_i);

	  json_attr_double (&json_ctx, "max", max / d_iters);

	  json_attr_double (&json_ctx, "min", min / d_iters);

	  json_attr_double (&json_ctx, "mean", d_total_s / d_total_i);

	}

      if (detailed && !is_bench)

	{

	  json_array_begin (&json_ctx, "timings");

	  for (int i = 0; i < NUM_SAMPLES (v); i++)

	    json_element_double (&json_ctx, RESULT (v, i));

	  json_array_end (&json_ctx);

	}

      /* End variant.  */

      json_attr_object_end (&json_ctx);

    }

  /* End function.  */

  json_attr_object_end (&json_ctx);

  return 0;

}