sync from github to svn: this version of atomic.h does not have compiler specific symbols. compiler specific optimization is to be merged in each port/<compiler>/<arch> directory.
diff --git a/FreeRTOS/Source/include/atomic.h b/FreeRTOS/Source/include/atomic.h
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+/*
+ * FreeRTOS Kernel V10.2.1
+ * Copyright (C) 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://www.FreeRTOS.org
+ * http://aws.amazon.com/freertos
+ *
+ * 1 tab == 4 spaces!
+ */
+
+/**
+ * @file atomic.h
+ * @brief FreeRTOS atomic operation support.
+ *
+ * This file implements atomic by disabling interrupts globally.
+ * Implementation with architecture specific atomic instructions
+ * are to be provided under each compiler directory.
+ */
+
+#ifndef ATOMIC_H
+#define ATOMIC_H
+
+#ifndef INC_FREERTOS_H
+ #error "include FreeRTOS.h must appear in source files before include atomic.h"
+#endif
+
+/* Standard includes. */
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Port specific definitions -- entering/exiting critical section.
+ * Refer template -- ./lib/FreeRTOS/portable/Compiler/Arch/portmacro.h
+ *
+ * Every call to ATOMIC_EXIT_CRITICAL() must be closely paired with
+ * ATOMIC_ENTER_CRITICAL().
+ * */
+#if defined( portSET_INTERRUPT_MASK_FROM_ISR )
+
+ /* Nested interrupt scheme is supported in this port. */
+ #define ATOMIC_ENTER_CRITICAL() \
+ UBaseType_t uxCriticalSectionType = portSET_INTERRUPT_MASK_FROM_ISR()
+
+ #define ATOMIC_EXIT_CRITICAL() \
+ portCLEAR_INTERRUPT_MASK_FROM_ISR( uxCriticalSectionType )
+
+#else
+
+ /* Nested interrupt scheme is NOT supported in this port. */
+ #define ATOMIC_ENTER_CRITICAL() portENTER_CRITICAL()
+ #define ATOMIC_EXIT_CRITICAL() portEXIT_CRITICAL()
+
+#endif /* portSET_INTERRUPT_MASK_FROM_ISR() */
+
+/* Port specific definition -- "always inline".
+ * Inline is compiler specific, and may not always get inlined depending on your optimization level.
+ * Also, inline is considerred as performance optimization for atomic.
+ * Thus, if portFORCE_INLINE is not provided by portmacro.h, instead of resulting error,
+ * simply define it.
+ */
+#ifndef portFORCE_INLINE
+ #define portFORCE_INLINE
+#endif
+
+#define ATOMIC_COMPARE_AND_SWAP_SUCCESS 0x1U /**< Compare and swap succeeded, swapped. */
+#define ATOMIC_COMPARE_AND_SWAP_FAILURE 0x0U /**< Compare and swap failed, did not swap. */
+
+/*----------------------------- Swap && CAS ------------------------------*/
+
+/**
+ * Atomic compare-and-swap
+ *
+ * @brief Performs an atomic compare-and-swap operation on the specified values.
+ *
+ * @param[in, out] pDestination Pointer to memory location from where value is
+ * to be loaded and checked.
+ * @param[in] ulExchange If condition meets, write this value to memory.
+ * @param[in] ulComparand Swap condition.
+ *
+ * @return Unsigned integer of value 1 or 0. 1 for swapped, 0 for not swapped.
+ *
+ * @note This function only swaps *pDestination with ulExchange, if previous
+ * *pDestination value equals ulComparand.
+ */
+static portFORCE_INLINE uint32_t Atomic_CompareAndSwap_u32(
+ uint32_t volatile * pDestination,
+ uint32_t ulExchange,
+ uint32_t ulComparand )
+{
+
+ uint32_t ulReturnValue = ATOMIC_COMPARE_AND_SWAP_FAILURE;
+
+ ATOMIC_ENTER_CRITICAL();
+
+ if ( *pDestination == ulComparand )
+ {
+ *pDestination = ulExchange;
+ ulReturnValue = ATOMIC_COMPARE_AND_SWAP_SUCCESS;
+ }
+
+ ATOMIC_EXIT_CRITICAL();
+
+ return ulReturnValue;
+
+}
+
+/**
+ * Atomic swap (pointers)
+ *
+ * @brief Atomically sets the address pointed to by *ppDestination to the value
+ * of *pExchange.
+ *
+ * @param[in, out] ppDestination Pointer to memory location from where a pointer
+ * value is to be loaded and written back to.
+ * @param[in] pExchange Pointer value to be written to *ppDestination.
+ *
+ * @return The initial value of *ppDestination.
+ */
+static portFORCE_INLINE void * Atomic_SwapPointers_p32(
+ void * volatile * ppDestination,
+ void * pExchange )
+{
+ void * pReturnValue;
+
+ ATOMIC_ENTER_CRITICAL();
+
+ pReturnValue = *ppDestination;
+
+ *ppDestination = pExchange;
+
+ ATOMIC_EXIT_CRITICAL();
+
+ return pReturnValue;
+}
+
+/**
+ * Atomic compare-and-swap (pointers)
+ *
+ * @brief Performs an atomic compare-and-swap operation on the specified pointer
+ * values.
+ *
+ * @param[in, out] ppDestination Pointer to memory location from where a pointer
+ * value is to be loaded and checked.
+ * @param[in] pExchange If condition meets, write this value to memory.
+ * @param[in] pComparand Swap condition.
+ *
+ * @return Unsigned integer of value 1 or 0. 1 for swapped, 0 for not swapped.
+ *
+ * @note This function only swaps *ppDestination with pExchange, if previous
+ * *ppDestination value equals pComparand.
+ */
+static portFORCE_INLINE uint32_t Atomic_CompareAndSwapPointers_p32(
+ void * volatile * ppDestination,
+ void * pExchange, void * pComparand )
+{
+ uint32_t ulReturnValue = ATOMIC_COMPARE_AND_SWAP_FAILURE;
+
+ ATOMIC_ENTER_CRITICAL();
+
+ if ( *ppDestination == pComparand )
+ {
+ *ppDestination = pExchange;
+ ulReturnValue = ATOMIC_COMPARE_AND_SWAP_SUCCESS;
+ }
+
+ ATOMIC_EXIT_CRITICAL();
+
+ return ulReturnValue;
+}
+
+
+/*----------------------------- Arithmetic ------------------------------*/
+
+/**
+ * Atomic add
+ *
+ * @brief Atomically adds count to the value of the specified pointer points to.
+ *
+ * @param[in,out] pAddend Pointer to memory location from where value is to be
+ * loaded and written back to.
+ * @param[in] ulCount Value to be added to *pAddend.
+ *
+ * @return previous *pAddend value.
+ */
+static portFORCE_INLINE uint32_t Atomic_Add_u32(
+ uint32_t volatile * pAddend,
+ uint32_t ulCount )
+{
+ uint32_t ulCurrent;
+
+ ATOMIC_ENTER_CRITICAL();
+
+ ulCurrent = *pAddend;
+
+ *pAddend += ulCount;
+
+ ATOMIC_EXIT_CRITICAL();
+
+ return ulCurrent;
+}
+
+/**
+ * Atomic subtract
+ *
+ * @brief Atomically subtracts count from the value of the specified pointer
+ * pointers to.
+ *
+ * @param[in,out] pAddend Pointer to memory location from where value is to be
+ * loaded and written back to.
+ * @param[in] ulCount Value to be subtract from *pAddend.
+ *
+ * @return previous *pAddend value.
+ */
+static portFORCE_INLINE uint32_t Atomic_Subtract_u32(
+ uint32_t volatile * pAddend,
+ uint32_t ulCount )
+{
+ uint32_t ulCurrent;
+
+ ATOMIC_ENTER_CRITICAL();
+
+ ulCurrent = *pAddend;
+
+ *pAddend -= ulCount;
+
+ ATOMIC_EXIT_CRITICAL();
+
+ return ulCurrent;
+}
+
+/**
+ * Atomic increment
+ *
+ * @brief Atomically increments the value of the specified pointer points to.
+ *
+ * @param[in,out] pAddend Pointer to memory location from where value is to be
+ * loaded and written back to.
+ *
+ * @return *pAddend value before increment.
+ */
+static portFORCE_INLINE uint32_t Atomic_Increment_u32( uint32_t volatile * pAddend )
+{
+ uint32_t ulCurrent;
+
+ ATOMIC_ENTER_CRITICAL();
+
+ ulCurrent = *pAddend;
+
+ *pAddend += 1;
+
+ ATOMIC_EXIT_CRITICAL();
+
+ return ulCurrent;
+}
+
+/**
+ * Atomic decrement
+ *
+ * @brief Atomically decrements the value of the specified pointer points to
+ *
+ * @param[in,out] pAddend Pointer to memory location from where value is to be
+ * loaded and written back to.
+ *
+ * @return *pAddend value before decrement.
+ */
+static portFORCE_INLINE uint32_t Atomic_Decrement_u32( uint32_t volatile * pAddend )
+{
+ uint32_t ulCurrent;
+
+ ATOMIC_ENTER_CRITICAL();
+
+ ulCurrent = *pAddend;
+
+ *pAddend -= 1;
+
+ ATOMIC_EXIT_CRITICAL();
+
+ return ulCurrent;
+}
+
+/*----------------------------- Bitwise Logical ------------------------------*/
+
+/**
+ * Atomic OR
+ *
+ * @brief Performs an atomic OR operation on the specified values.
+ *
+ * @param [in, out] pDestination Pointer to memory location from where value is
+ * to be loaded and written back to.
+ * @param [in] ulValue Value to be ORed with *pDestination.
+ *
+ * @return The original value of *pDestination.
+ */
+static portFORCE_INLINE uint32_t Atomic_OR_u32(
+ uint32_t volatile * pDestination,
+ uint32_t ulValue )
+{
+ uint32_t ulCurrent;
+
+ ATOMIC_ENTER_CRITICAL();
+
+ ulCurrent = *pDestination;
+
+ *pDestination |= ulValue;
+
+ ATOMIC_EXIT_CRITICAL();
+
+ return ulCurrent;
+}
+
+/**
+ * Atomic AND
+ *
+ * @brief Performs an atomic AND operation on the specified values.
+ *
+ * @param [in, out] pDestination Pointer to memory location from where value is
+ * to be loaded and written back to.
+ * @param [in] ulValue Value to be ANDed with *pDestination.
+ *
+ * @return The original value of *pDestination.
+ */
+static portFORCE_INLINE uint32_t Atomic_AND_u32(
+ uint32_t volatile * pDestination,
+ uint32_t ulValue )
+{
+ uint32_t ulCurrent;
+
+ ATOMIC_ENTER_CRITICAL();
+
+ ulCurrent = *pDestination;
+
+ *pDestination &= ulValue;
+
+ ATOMIC_EXIT_CRITICAL();
+
+ return ulCurrent;
+}
+
+/**
+ * Atomic NAND
+ *
+ * @brief Performs an atomic NAND operation on the specified values.
+ *
+ * @param [in, out] pDestination Pointer to memory location from where value is
+ * to be loaded and written back to.
+ * @param [in] ulValue Value to be NANDed with *pDestination.
+ *
+ * @return The original value of *pDestination.
+ */
+static portFORCE_INLINE uint32_t Atomic_NAND_u32(
+ uint32_t volatile * pDestination,
+ uint32_t ulValue )
+{
+ uint32_t ulCurrent;
+
+ ATOMIC_ENTER_CRITICAL();
+
+ ulCurrent = *pDestination;
+
+ *pDestination = ~(ulCurrent & ulValue);
+
+ ATOMIC_EXIT_CRITICAL();
+
+ return ulCurrent;
+}
+
+/**
+ * Atomic XOR
+ *
+ * @brief Performs an atomic XOR operation on the specified values.
+ *
+ * @param [in, out] pDestination Pointer to memory location from where value is
+ * to be loaded and written back to.
+ * @param [in] ulValue Value to be XORed with *pDestination.
+ *
+ * @return The original value of *pDestination.
+ */
+static portFORCE_INLINE uint32_t Atomic_XOR_u32(
+ uint32_t volatile * pDestination,
+ uint32_t ulValue )
+{
+ uint32_t ulCurrent;
+
+ ATOMIC_ENTER_CRITICAL();
+
+ ulCurrent = *pDestination;
+
+ *pDestination ^= ulValue;
+
+ ATOMIC_EXIT_CRITICAL();
+
+ return ulCurrent;
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ATOMIC_H */
