arch_misc.h — 架构杂项工具接口头文件

源文件路径: arch/arm/armv7m/include/arch_misc.h

引用章节: 4.2 任务管理

完整源码

/**
 ***********************************************************************************************************************
 * Copyright (c) 2020, China Mobile Communications Group Co.,Ltd.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with 
 * the License. You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on 
 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the 
 * specific language governing permissions and limitations under the License.
 *
 * @file        arch_misc.h
 *
 * @brief       Header file for misc related functions.
 *
 * @revision
 * Date         Author          Notes
 * 2021-01-12   OneOS Team      First version.
 ***********************************************************************************************************************
 */

#ifndef __ARCH_MISC_H__
#define __ARCH_MISC_H__

#include <os_types.h>

#ifdef __cplusplus
extern "C" {
#endif

extern int32_t os_ffs(uint32_t value);
extern int32_t os_fls(uint32_t value);
extern void      *os_get_current_task_sp(void);
extern void      *_arch_get_interrupt_sp(void);

#ifdef __cplusplus
}
#endif

#endif /* __ARCH_MISC_H__ */

关键说明

模块	说明
os_ffs	Find First Set：查找最低位 1 的位置（从 1 开始计数），ARMv7-M 使用 RBIT+CLZ 指令实现
os_fls	Find Last Set：查找最高位 1 的位置（从 1 开始计数），纯 C 二分查找实现
os_get_current_task_sp	获取当前任务栈指针（读取 PSP 寄存器），用于栈使用量检测和异常信息收集
_arch_get_interrupt_sp	获取中断栈