From cf204e72ea5fd6e4be8b3295cb148fde5fdd47d2 Mon Sep 17 00:00:00 2001 From: Giovanni Di Sirio Date: Tue, 16 Feb 2016 10:07:00 +0000 Subject: Tree reorganization. git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@8900 35acf78f-673a-0410-8e92-d51de3d6d3f4 --- os/rt/include/chalign.h | 114 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 os/rt/include/chalign.h (limited to 'os/rt/include/chalign.h') diff --git a/os/rt/include/chalign.h b/os/rt/include/chalign.h new file mode 100644 index 000000000..198e50da3 --- /dev/null +++ b/os/rt/include/chalign.h @@ -0,0 +1,114 @@ +/* + ChibiOS - Copyright (C) 2006..2015 Giovanni Di Sirio. + + This file is part of ChibiOS. + + ChibiOS is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + ChibiOS 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +/** + * @file chmem.h + * @brief Memory alignment macros and structures. + * + * @addtogroup mem + * @{ + */ + +#ifndef _CHALIGN_H_ +#define _CHALIGN_H_ + +/*===========================================================================*/ +/* Module constants. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Module pre-compile time settings. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Derived constants and error checks. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Module data structures and types. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Module macros. */ +/*===========================================================================*/ + +/** + * @name Memory alignment support macros + */ +/** + * @brief Alignment mask constant. + * + * @param[in] a alignment, must be a power of two + */ +#define MEM_ALIGN_MASK(a) ((size_t)(a) - 1U) + +/** + * @brief Aligns to the previous aligned memory address. + * + * @param[in] p variable to be aligned + * @param[in] a alignment, must be a power of two + */ +#define MEM_ALIGN_PREV(p, a) ((size_t)(p) & ~MEM_ALIGN_MASK(a)) + +/** + * @brief Aligns to the new aligned memory address. + * + * @param[in] p variable to be aligned + * @param[in] a alignment, must be a power of two + */ +#define MEM_ALIGN_NEXT(p, a) MEM_ALIGN_PREV((size_t)(p) + \ + MEM_ALIGN_MASK(a), (a)) + +/** + * @brief Returns whatever a pointer or memory size is aligned. + * + * @param[in] p variable to be aligned + * @param[in] a alignment, must be a power of two + */ +#define MEM_IS_ALIGNED(p, a) (((size_t)(p) & MEM_ALIGN_MASK(a)) == 0U) + +/** + * @brief Returns whatever a constant is a valid alignment. + * @details Valid alignments are powers of two. + * + * @param[in] a alignment to be checked, must be a constant + */ +#define MEM_IS_VALID_ALIGNMENT(a) \ + (((size_t)(a) != 0U) && (((size_t)(a) & ((size_t)(a) - 1U)) == 0U)) +/** @} */ + +/*===========================================================================*/ +/* External declarations. */ +/*===========================================================================*/ + +#ifdef __cplusplus +extern "C" { +#endif + +#ifdef __cplusplus +} +#endif + +/*===========================================================================*/ +/* Module inline functions. */ +/*===========================================================================*/ + +#endif /* _CHALIGN_H_ */ + +/** @} */ -- cgit v1.2.3