Merge from libretro/master:46902e0 for repo synchronization

platform/libretro/libretro-common/include/compat/intrinsics.h

@@ -0,0 +1,85 @@
+/* Copyright  (C) 2010-2018 The RetroArch team
+ *
+ * ---------------------------------------------------------------------------------------
+ * The following license statement only applies to this file (intrinsics.h).
+ * ---------------------------------------------------------------------------------------
+ *
+ * Permission is hereby granted, free of charge,
+ * to any person obtaining a copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+ * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef __LIBRETRO_SDK_COMPAT_INTRINSICS_H
+#define __LIBRETRO_SDK_COMPAT_INTRINSICS_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <string.h>
+
+#include <retro_common_api.h>
+#include <retro_inline.h>
+
+#if defined(_MSC_VER) && !defined(_XBOX)
+#if (_MSC_VER > 1310)
+#include <intrin.h>
+#endif
+#endif
+
+RETRO_BEGIN_DECLS
+
+/* Count Leading Zero, unsigned 16bit input value */
+static INLINE unsigned compat_clz_u16(uint16_t val)
+{
+#if defined(__GNUC__) && !defined(PS2)
+   return __builtin_clz(val << 16 | 0x8000);
+#else
+   unsigned ret = 0;
+
+   while(!(val & 0x8000) && ret < 16)
+   {
+      val <<= 1;
+      ret++;
+   }
+
+   return ret;
+#endif
+}
+
+/* Count Trailing Zero */
+static INLINE int compat_ctz(unsigned x)
+{
+#if defined(__GNUC__) && !defined(RARCH_CONSOLE)
+   return __builtin_ctz(x);
+#elif _MSC_VER >= 1400 && !defined(_XBOX) && !defined(__WINRT__)
+   unsigned long r = 0;
+   _BitScanReverse((unsigned long*)&r, x);
+   return (int)r;
+#else
+/* Only checks at nibble granularity,
+ * because that's what we need. */
+   if (x & 0x000f)
+      return 0;
+   if (x & 0x00f0)
+      return 4;
+   if (x & 0x0f00)
+      return 8;
+   if (x & 0xf000)
+      return 12;
+   return 16;
+#endif
+}
+
+RETRO_END_DECLS
+
+#endif