rtpdec: Cosmetic cleanup of the header

[ffmpeg] / libavutil / intmath.h

diff --git a/libavutil/intmath.h b/libavutil/intmath.h
index 7aff78ceb15d4a21af8a7e98809fdf0081733767..a5ee6525ee31436586970b924191795a7630ae18 100644 (file)
--- a/libavutil/intmath.h
+++ b/libavutil/intmath.h
@@ -1,59 +1,146 @@
 /*
  * Copyright (c) 2010 Mans Rullgard <mans@mansr.com>
  *
- * This file is part of FFmpeg.
+ * This file is part of Libav.
  *
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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.
  *
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav 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 FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #ifndef AVUTIL_INTMATH_H
 #define AVUTIL_INTMATH_H
 
-#include "config.h"
-#include "common.h"
+#include <stdint.h>
 
-extern const uint32_t ff_inverse[257];
+#include "config.h"
+#include "attributes.h"
 
-#if   ARCH_ARM
+#if ARCH_ARM
 #   include "arm/intmath.h"
-#elif ARCH_X86
-#   include "x86/intmath.h"
 #endif
 
+/**
+ * @addtogroup lavu_internal
+ * @{
+ */
+
 #if HAVE_FAST_CLZ && AV_GCC_VERSION_AT_LEAST(3,4)
 
-#ifndef av_log2
+#ifndef ff_log2
+#   define ff_log2(x) (31 - __builtin_clz((x)|1))
+#   ifndef ff_log2_16bit
+#      define ff_log2_16bit av_log2
+#   endif
+#endif /* ff_log2 */
+
+#endif /* AV_GCC_VERSION_AT_LEAST(3,4) */
+
+extern const uint8_t ff_log2_tab[256];
 
-#define av_log2(x) (31 - __builtin_clz((x)|1))
+#ifndef ff_log2
+#define ff_log2 ff_log2_c
+static av_always_inline av_const int ff_log2_c(unsigned int v)
+{
+    int n = 0;
+    if (v & 0xffff0000) {
+        v >>= 16;
+        n += 16;
+    }
+    if (v & 0xff00) {
+        v >>= 8;
+        n += 8;
+    }
+    n += ff_log2_tab[v];
 
-#ifndef av_log2_16bit
-#define av_log2_16bit av_log2
+    return n;
+}
 #endif
 
-#endif /* av_log2 */
+#ifndef ff_log2_16bit
+#define ff_log2_16bit ff_log2_16bit_c
+static av_always_inline av_const int ff_log2_16bit_c(unsigned int v)
+{
+    int n = 0;
+    if (v & 0xff00) {
+        v >>= 8;
+        n += 8;
+    }
+    n += ff_log2_tab[v];
 
-#endif /* AV_GCC_VERSION_AT_LEAST(3,4) */
+    return n;
+}
+#endif
 
-#ifndef FASTDIV
+#define av_log2       ff_log2
+#define av_log2_16bit ff_log2_16bit
 
-#if CONFIG_FASTDIV
-#    define FASTDIV(a,b)   ((uint32_t)((((uint64_t)a) * ff_inverse[b]) >> 32))
-#else
-#    define FASTDIV(a,b)   ((a) / (b))
+/**
+ * @}
+ */
+
+/**
+ * @addtogroup lavu_math
+ * @{
+ */
+
+#if HAVE_FAST_CLZ && AV_GCC_VERSION_AT_LEAST(3,4)
+#ifndef ff_ctz
+#define ff_ctz(v) __builtin_ctz(v)
+#endif
 #endif
 
-#endif /* FASTDIV */
+#ifndef ff_ctz
+#define ff_ctz ff_ctz_c
+static av_always_inline av_const int ff_ctz_c(int v)
+{
+    int c;
 
+    if (v & 0x1)
+        return 0;
+
+    c = 1;
+    if (!(v & 0xffff)) {
+        v >>= 16;
+        c += 16;
+    }
+    if (!(v & 0xff)) {
+        v >>= 8;
+        c += 8;
+    }
+    if (!(v & 0xf)) {
+        v >>= 4;
+        c += 4;
+    }
+    if (!(v & 0x3)) {
+        v >>= 2;
+        c += 2;
+    }
+    c -= v & 0x1;
+
+    return c;
+}
+#endif
+
+/**
+ * Trailing zero bit count.
+ *
+ * @param v  input value. If v is 0, the result is undefined.
+ * @return   the number of trailing 0-bits
+ */
+int av_ctz(int v);
+
+/**
+ * @}
+ */
 #endif /* AVUTIL_INTMATH_H */