aom_ports/mem.h

   1 /*
   2  * Copyright (c) 2016, Alliance for Open Media. All rights reserved
   3  *
   4  * This source code is subject to the terms of the BSD 2 Clause License and
   5  * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
   6  * was not distributed with this source code in the LICENSE file, you can
   7  * obtain it at www.aomedia.org/license/software. If the Alliance for Open
   8  * Media Patent License 1.0 was not distributed with this source code in the
   9  * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
  10  */
  11
  12 #ifndef AOM_PORTS_MEM_H_
  13 #define AOM_PORTS_MEM_H_
  14
  15 #include "aom_config.h"
  16 #include "aom/aom_integer.h"
  17
  18 #if (defined(__GNUC__) && __GNUC__) || defined(__SUNPRO_C)
  19 #define DECLARE_ALIGNED(n, typ, val) typ val __attribute__((aligned(n)))
  20 #elif defined(_MSC_VER)
  21 #define DECLARE_ALIGNED(n, typ, val) __declspec(align(n)) typ val
  22 #else
  23 #warning No alignment directives known for this compiler.
  24 #define DECLARE_ALIGNED(n, typ, val) typ val
  25 #endif
  26
  27 /* Indicates that the usage of the specified variable has been audited to assure
  28  * that it's safe to use uninitialized. Silences 'may be used uninitialized'
  29  * warnings on gcc.
  30  */
  31 #if defined(__GNUC__) && __GNUC__
  32 #define UNINITIALIZED_IS_SAFE(x) x = x
  33 #else
  34 #define UNINITIALIZED_IS_SAFE(x) x
  35 #endif
  36
  37 #if HAVE_NEON && defined(_MSC_VER)
  38 #define __builtin_prefetch(x)
  39 #endif
  40
  41 /* Shift down with rounding for use when n >= 0, value >= 0 */
  42 #define ROUND_POWER_OF_TWO(value, n) (((value) + (((1 << (n)) >> 1))) >> (n))
  43
  44 /* Shift down with rounding for signed integers, for use when n >= 0 */
  45 #define ROUND_POWER_OF_TWO_SIGNED(value, n)           \
  46   (((value) < 0) ? -ROUND_POWER_OF_TWO(-(value), (n)) \
  47                  : ROUND_POWER_OF_TWO((value), (n)))
  48
  49 /* Shift down with rounding for use when n >= 0, value >= 0 for (64 bit) */
  50 #define ROUND_POWER_OF_TWO_64(value, n) \
  51   (((value) + ((((int64_t)1 << (n)) >> 1))) >> (n))
  52 /* Shift down with rounding for signed integers, for use when n >= 0 (64 bit) */
  53 #define ROUND_POWER_OF_TWO_SIGNED_64(value, n)           \
  54   (((value) < 0) ? -ROUND_POWER_OF_TWO_64(-(value), (n)) \
  55                  : ROUND_POWER_OF_TWO_64((value), (n)))
  56
  57 /* shift right or left depending on sign of n */
  58 #define RIGHT_SIGNED_SHIFT(value, n) \
  59   ((n) < 0 ? ((value) << (-(n))) : ((value) >> (n)))
  60
  61 #define ALIGN_POWER_OF_TWO(value, n) \
  62   (((value) + ((1 << (n)) - 1)) & ~((1 << (n)) - 1))
  63
  64 #define DIVIDE_AND_ROUND(x, y) (((x) + ((y) >> 1)) / (y))
  65
  66 #define CONVERT_TO_SHORTPTR(x) ((uint16_t *)(((uintptr_t)(x)) << 1))
  67 #define CONVERT_TO_BYTEPTR(x) ((uint8_t *)(((uintptr_t)(x)) >> 1))
  68
  69 #endif  // AOM_PORTS_MEM_H_