/*
  This file is part of Ingen.
  Copyright 2007-2012 David Robillard <http://drobilla.net/>

  Ingen is free software: you can redistribute it and/or modify it under the
  terms of the GNU Affero General Public License as published by the Free
  Software Foundation, either version 3 of the License, or any later version.

  Ingen 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 Affero General Public License for details.

  You should have received a copy of the GNU Affero General Public License
  along with Ingen.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef INGEN_ENGINE_UTIL_HPP
#define INGEN_ENGINE_UTIL_HPP

#include <cstdlib>

#include "raul/log.hpp"
#include "raul/Path.hpp"

#include "ingen_config.h"

#include <fenv.h>
#ifdef __SSE__
#include <xmmintrin.h>
#endif

#ifdef __clang__
#    define REALTIME __attribute__((annotate("realtime")))
#else
#    define REALTIME
#endif

#ifdef USE_ASSEMBLY
# if SIZEOF_VOID_P==8
#  define cpuid(a, b, c, d, n) asm("xchgq %%rbx, %1; cpuid; xchgq %%rbx, %1": "=a" (a), "=r" (b), "=c" (c), "=d" (d) : "a" (n));
# else
#  define cpuid(a, b, c, d, n) asm("xchgl %%ebx, %1; cpuid; xchgl %%ebx, %1": "=a" (a), "=r" (b), "=c" (c), "=d" (d) : "a" (n));
# endif
#endif

namespace Ingen {
namespace Server {

/** Set flags to disable denormal processing.
 */
inline void
set_denormal_flags()
{
#ifdef USE_ASSEMBLY
#ifdef __SSE__
	unsigned long a, b, c, d0, d1;
	cpuid(a, b, c, d1, 1);
	if (d1 & 1<<25) { /* It has SSE support */
		_MM_SET_FLUSH_ZERO_MODE(_MM_FLUSH_ZERO_ON);
		const int family    = (a >> 8)  & 0xF;
		const int extfamily = (a >> 20) & 0xFF;
		const int model     = (a >> 4)  & 0xF;
		const int stepping  = a         & 0xF;
		cpuid(a, b, c, d0, 0);
		if (b == 0x756e6547) { /* It's an Intel */
			if (family == 15 && extfamily == 0 && model == 0 && stepping < 7) {
				return;
			}
		}
		if (d1 & 1<<26) { /* bit 26, SSE2 support */
			_mm_setcsr(_mm_getcsr() | 0x8040); // set DAZ and FZ bits of MXCSR
			Raul::info << "Set SSE denormal fix flag" << endl;
		}
	} else {
		Raul::warn << "This code has been built with SSE support, but your processor does"
		           << " not support the SSE instruction set, exiting." << std::endl;
		exit(EXIT_FAILURE);
	}
#endif
#endif
}

} // namespace Server
} // namespace Ingen

#endif // INGEN_ENGINE_UTIL_HPP