1 /* 2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 12 #ifndef VPX_PORTS_MEM_H 13 #define VPX_PORTS_MEM_H 14 #include "vpx_config.h" 15 #include "vpx/vpx_integer.h" 16 17 #if defined(__GNUC__) && __GNUC__ 18 #define DECLARE_ALIGNED(n,typ,val) typ val __attribute__ ((aligned (n))) 19 #elif defined(_MSC_VER) 20 #define DECLARE_ALIGNED(n,typ,val) __declspec(align(n)) typ val 21 #else 22 #warning No alignment directives known for this compiler. 23 #define DECLARE_ALIGNED(n,typ,val) typ val 24 #endif 25 #endif 26 27 28 /* Declare an aligned array on the stack, for situations where the stack 29 * pointer may not have the alignment we expect. Creates an array with a 30 * modified name, then defines val to be a pointer, and aligns that pointer 31 * within the array. 32 */ 33 #define DECLARE_ALIGNED_ARRAY(a,typ,val,n)\ 34 typ val##_[(n)+(a)/sizeof(typ)+1];\ 35 typ *val = (typ*)((((intptr_t)val##_)+(a)-1)&((intptr_t)-(a))) 36 37 38 /* Indicates that the usage of the specified variable has been audited to assure 39 * that it's safe to use uninitialized. Silences 'may be used uninitialized' 40 * warnings on gcc. 41 */ 42 #if defined(__GNUC__) && __GNUC__ 43 #define UNINITIALIZED_IS_SAFE(x) x=x 44 #else 45 #define UNINITIALIZED_IS_SAFE(x) x 46 #endif 47