/* rhash_timing.c - functions to benchmark hash algorithms,
 *
 * Copyright (c) 2010, Aleksey Kravchenko <rhash.admin@gmail.com>
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE  INCLUDING ALL IMPLIED WARRANTIES OF  MERCHANTABILITY
 * AND FITNESS.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
 * INDIRECT,  OR CONSEQUENTIAL DAMAGES  OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE,  DATA OR PROFITS,  WHETHER IN AN ACTION OF CONTRACT,  NEGLIGENCE
 * OR OTHER TORTIOUS ACTION,  ARISING OUT OF  OR IN CONNECTION  WITH THE USE  OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

/* modifier for Windows dll */
#if (defined(_WIN32) || defined(__CYGWIN__)) && defined(RHASH_EXPORTS)
# define RHASH_API __declspec(dllexport)
#endif

#include "byte_order.h"
#include "rhash.h"
#include "rhash_timing.h"

/* DEFINE read_tsc() if possible */

#if (defined(CPU_IA32)) || defined(CPU_X64)

#if defined( _MSC_VER ) /* if MS VC */
# include <intrin.h>
# pragma intrinsic( __rdtsc )
# define read_tsc() __rdtsc()
# define HAVE_TSC
#elif defined( __GNUC__ ) /* if GCC */
static uint64_t read_tsc(void) {
	unsigned long lo, hi;
	__asm volatile("rdtsc" : "=a" (lo), "=d" (hi));
	return (((uint64_t)hi) << 32) + lo;
}
# define HAVE_TSC
#endif /* _MSC_VER, __GNUC__ */
#endif /* CPU_IA32, CPU_X64 */


/* TIMER FUNCTIONS */

#if defined(_WIN32) || defined(__CYGWIN__)
#include <windows.h>
#define get_timedelta(delta) QueryPerformanceCounter((LARGE_INTEGER*)delta)
#else
#define get_timedelta(delta) gettimeofday(delta, NULL)
#endif

/**
 * Return real-value representing number of seconds
 * stored in the given timeval structure.
 * The function is used with timers, when printing time statistics.
 *
 * @deprecated This function shall be removed soon.
 *
 * @param delta time delta to be converted
 * @return number of seconds
 */
static double fsec(timedelta_t* timer)
{
#if defined(_WIN32) || defined(__CYGWIN__)
	LARGE_INTEGER freq;
	QueryPerformanceFrequency(&freq);
	return (double)*timer / freq.QuadPart;
#else
	return ((double)timer->tv_usec / 1000000.0) + timer->tv_sec;
#endif
}

void rhash_timer_start(timedelta_t* timer)
{
	get_timedelta(timer);
}

double rhash_timer_stop(timedelta_t* timer)
{
	timedelta_t end;
	get_timedelta(&end);
#if defined(_WIN32) || defined(__CYGWIN__)
	*timer = end - *timer;
#else
	timer->tv_sec  = end.tv_sec  - timer->tv_sec - (end.tv_usec >= timer->tv_usec ? 0 : 1);
	timer->tv_usec = end.tv_usec + (end.tv_usec >= timer->tv_usec ? 0 : 1000000 ) - timer->tv_usec;
#endif
	return fsec(timer);
}

#if defined(_WIN32) || defined(__CYGWIN__)
/**
 * Set process priority and affinity to use all cpu's but the first one.
 * This improves benchmark results on a multi-cpu systems.
 *
 * @deprecated This function shall be removed soon.
 */
static void benchmark_cpu_init(void)
{
	DWORD_PTR dwProcessMask, dwSysMask, dwDesired;

	SetPriorityClass(GetCurrentProcess(), HIGH_PRIORITY_CLASS);
	SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_HIGHEST);

	if ( GetProcessAffinityMask(GetCurrentProcess(), &dwProcessMask, &dwSysMask) ) {
		dwDesired = dwSysMask & (dwProcessMask & ~1); /* remove the first processor */
		dwDesired = (dwDesired ? dwDesired : dwSysMask & ~1);
		if (dwDesired != 0) {
			SetProcessAffinityMask(GetCurrentProcess(), dwDesired);
		}
	}
}
#endif

/**
 * Hash a repeated message chunk by specified hash function.
 *
 * @deprecated This function shall be removed soon.
 *
 * @param hash_id hash function identifier
 * @param message a message chunk to hash
 * @param msg_size message chunk size
 * @param count number of chunks
 * @param out computed hash
 * @return 1 on success, 0 on error
 */
static int hash_in_loop(unsigned hash_id, const unsigned char* message, size_t msg_size, int count, unsigned char* out)
{
	int i;
	struct rhash_context* context = rhash_init(hash_id);
	if (!context) return 0;

	/* process the repeated message buffer */
	for (i = 0; i < count; i++) rhash_update(context, message, msg_size);
	rhash_final(context, out);
	rhash_free(context);
	return 1;
}

void rhash_run_benchmark(unsigned hash_id, unsigned flags, FILE* output)
{
	unsigned char ALIGN_ATTR(64) message[8192]; /* 8 KiB */
	timedelta_t timer;
	int i, j;
	size_t sz_mb, msg_size;
	double time, total_time = 0;
	const int rounds = 4;
	const char* hash_name;
	unsigned char out[130];
#ifdef HAVE_TSC
	double cpb = 0;
#endif /* HAVE_TSC */

#if defined(_WIN32) || defined(__CYGWIN__)
	benchmark_cpu_init(); /* set cpu affinity to improve test results */
#endif

	/* set message size for fast and slow hash functions */
	msg_size = 1073741824 / 2;
	if (hash_id & (RHASH_WHIRLPOOL | RHASH_SNEFRU128 | RHASH_SNEFRU256 | RHASH_SHA3_224 | RHASH_SHA3_256 | RHASH_SHA3_384 | RHASH_SHA3_512)) {
		msg_size /= 8;
	} else if (hash_id & (RHASH_GOST94 | RHASH_GOST94_CRYPTOPRO | RHASH_SHA384 | RHASH_SHA512)) {
		msg_size /= 2;
	}
	sz_mb = msg_size / (1 << 20); /* size in MiB */
	hash_name = rhash_get_name(hash_id);
	if (!hash_name) hash_name = ""; /* benchmarking several hashes*/

	for (i = 0; i < (int)sizeof(message); i++) message[i] = i & 0xff;

	for (j = 0; j < rounds; j++) {
		rhash_timer_start(&timer);
		hash_in_loop(hash_id, message, sizeof(message), (int)(msg_size / sizeof(message)), out);

		time = rhash_timer_stop(&timer);
		total_time += time;

		if ((flags & (RHASH_BENCHMARK_QUIET | RHASH_BENCHMARK_RAW)) == 0) {
			fprintf(output, "%s %u MiB calculated in %.3f sec, %.3f MBps\n", hash_name, (unsigned)sz_mb, time, (double)sz_mb / time);
			fflush(output);
		}
	}

#if defined(HAVE_TSC)
	/* measure the CPU "clocks per byte" speed */
	if (flags & RHASH_BENCHMARK_CPB) {
		unsigned int c1 = -1, c2 = -1;
		unsigned volatile long long cy0, cy1, cy2;
		int msg_size = 128 * 1024;

		/* make 200 tries */
		for (i = 0; i < 200; i++) {
			cy0 = read_tsc();
			hash_in_loop(hash_id, message, sizeof(message), msg_size / sizeof(message), out);
			cy1 = read_tsc();
			hash_in_loop(hash_id, message, sizeof(message), msg_size / sizeof(message), out);
			hash_in_loop(hash_id, message, sizeof(message), msg_size / sizeof(message), out);
			cy2 = read_tsc();

			cy2 -= cy1;
			cy1 -= cy0;
			c1 = (unsigned int)(c1 > cy1 ? cy1 : c1);
			c2 = (unsigned int)(c2 > cy2 ? cy2 : c2);
		}
		cpb = ((c2 - c1) + 1) / (double)msg_size;
	}
#endif /* HAVE_TSC */

	if (flags & RHASH_BENCHMARK_RAW) {
		/* output result in a "raw" machine-readable format */
		fprintf(output, "%s\t%u\t%.3f\t%.3f", hash_name, ((unsigned)sz_mb * rounds), total_time, (double)(sz_mb * rounds) / total_time);
#if defined(HAVE_TSC)
		if (flags & RHASH_BENCHMARK_CPB) fprintf(output, "\t%.2f", cpb);
#endif /* HAVE_TSC */
		fprintf(output, "\n");
	} else {
		fprintf(output, "%s %u MiB total in %.3f sec, %.3f MBps", hash_name, ((unsigned)sz_mb * rounds), total_time, (double)(sz_mb * rounds) / total_time);
#if defined(HAVE_TSC)
		if (flags & RHASH_BENCHMARK_CPB) fprintf(output, ", CPB=%.2f", cpb);
#endif /* HAVE_TSC */
		fprintf(output, "\n");
	}
}
