/* GStreamer
 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
 *                    2000 Wim Taymans <wtay@chello.be>
 *
 * gstcpu.c: CPU detection and architecture-specific routines
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include <glib.h>

#include "gst_private.h"
#include "gstcpu.h"

static guint32 _gst_cpu_flags;

#ifdef HAVE_CPU_I386
void gst_cpuid_i386 (int, unsigned long *, unsigned long *, unsigned long *, unsigned long *);
#define gst_cpuid gst_cpuid_i386
#else
#define gst_cpuid(o,a,b,c,d) (void)(a);(void)(b);(void)(c);
#endif

static gchar *
stringcat (gchar * a, gchar * b)
{
  gchar *c;

  if (a) {
    c = g_strconcat (a, b, NULL);
    g_free (a);
  }
  else {
    c = g_strdup (b);
  }
  return c;
}


void
_gst_cpu_initialize (void)
{
  gchar *featurelist = NULL;
  gboolean AMD;

  gulong eax = 0, ebx = 0, ecx = 0, edx = 0;

  gst_cpuid (0, &eax, &ebx, &ecx, &edx);

  AMD = (ebx == 0x68747541) && (ecx == 0x444d4163) && (edx == 0x69746e65);

  gst_cpuid (1, &eax, &ebx, &ecx, &edx);

  if (edx & (1 << 23)) {
    _gst_cpu_flags |= GST_CPU_FLAG_MMX;
    featurelist = stringcat (featurelist, "MMX ");

    if (edx & (1 << 25)) {
      _gst_cpu_flags |= GST_CPU_FLAG_SSE;
      _gst_cpu_flags |= GST_CPU_FLAG_MMXEXT;
      featurelist = stringcat (featurelist, "SSE ");
    }

    gst_cpuid (0x80000000, &eax, &ebx, &ecx, &edx);

    if (eax >= 0x80000001) {

      gst_cpuid (0x80000001, &eax, &ebx, &ecx, &edx);

      if (edx & (1 << 31)) {
	_gst_cpu_flags |= GST_CPU_FLAG_3DNOW;
	featurelist = stringcat (featurelist, "3DNOW ");
      }
      if (AMD && (edx & (1 << 22))) {
	_gst_cpu_flags |= GST_CPU_FLAG_MMXEXT;
	featurelist = stringcat (featurelist, "MMXEXT ");
      }
    }
  }

  if (!_gst_cpu_flags) {
    featurelist = stringcat (featurelist, "NONE");
  }

  GST_INFO (GST_CAT_GST_INIT, "CPU features: (%08lx) %s", edx, featurelist);
  g_free (featurelist);
}

GstCPUFlags
gst_cpu_get_flags (void)
{
  return _gst_cpu_flags;
}