/*
Simple DirectMedia Layer
- Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
+ Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
* All of the atomic operations that modify memory are full memory barriers.
*/
-#ifndef _SDL_atomic_h_
-#define _SDL_atomic_h_
+#ifndef SDL_atomic_h_
+#define SDL_atomic_h_
#include "SDL_stdinc.h"
#include "SDL_platform.h"
* The compiler barrier prevents the compiler from reordering
* reads and writes to globally visible variables across the call.
*/
-#if defined(_MSC_VER) && (_MSC_VER > 1200)
+#if defined(_MSC_VER) && (_MSC_VER > 1200) && !defined(__clang__)
void _ReadWriteBarrier(void);
#pragma intrinsic(_ReadWriteBarrier)
#define SDL_CompilerBarrier() _ReadWriteBarrier()
#elif (defined(__GNUC__) && !defined(__EMSCRIPTEN__)) || (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x5120))
/* This is correct for all CPUs when using GCC or Solaris Studio 12.1+. */
#define SDL_CompilerBarrier() __asm__ __volatile__ ("" : : : "memory")
+#elif defined(__WATCOMC__)
+extern _inline void SDL_CompilerBarrier (void);
+#pragma aux SDL_CompilerBarrier = "" parm [] modify exact [];
#else
#define SDL_CompilerBarrier() \
{ SDL_SpinLock _tmp = 0; SDL_AtomicLock(&_tmp); SDL_AtomicUnlock(&_tmp); }
* For more information on these semantics, take a look at the blog post:
* http://preshing.com/20120913/acquire-and-release-semantics
*/
+extern DECLSPEC void SDLCALL SDL_MemoryBarrierReleaseFunction(void);
+extern DECLSPEC void SDLCALL SDL_MemoryBarrierAcquireFunction(void);
+
#if defined(__GNUC__) && (defined(__powerpc__) || defined(__ppc__))
#define SDL_MemoryBarrierRelease() __asm__ __volatile__ ("lwsync" : : : "memory")
#define SDL_MemoryBarrierAcquire() __asm__ __volatile__ ("lwsync" : : : "memory")
+#elif defined(__GNUC__) && defined(__aarch64__)
+#define SDL_MemoryBarrierRelease() __asm__ __volatile__ ("dmb ish" : : : "memory")
+#define SDL_MemoryBarrierAcquire() __asm__ __volatile__ ("dmb ish" : : : "memory")
#elif defined(__GNUC__) && defined(__arm__)
-#if defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7EM__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__)
+#if 0 /* defined(__LINUX__) || defined(__ANDROID__) */
+/* Information from:
+ https://chromium.googlesource.com/chromium/chromium/+/trunk/base/atomicops_internals_arm_gcc.h#19
+
+ The Linux kernel provides a helper function which provides the right code for a memory barrier,
+ hard-coded at address 0xffff0fa0
+*/
+typedef void (*SDL_KernelMemoryBarrierFunc)();
+#define SDL_MemoryBarrierRelease() ((SDL_KernelMemoryBarrierFunc)0xffff0fa0)()
+#define SDL_MemoryBarrierAcquire() ((SDL_KernelMemoryBarrierFunc)0xffff0fa0)()
+#elif 0 /* defined(__QNXNTO__) */
+#include <sys/cpuinline.h>
+
+#define SDL_MemoryBarrierRelease() __cpu_membarrier()
+#define SDL_MemoryBarrierAcquire() __cpu_membarrier()
+#else
+#if defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7EM__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__) || defined(__ARM_ARCH_8A__)
#define SDL_MemoryBarrierRelease() __asm__ __volatile__ ("dmb ish" : : : "memory")
#define SDL_MemoryBarrierAcquire() __asm__ __volatile__ ("dmb ish" : : : "memory")
-#elif defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6T2__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__)
+#elif defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6T2__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_5TE__)
#ifdef __thumb__
/* The mcr instruction isn't available in thumb mode, use real functions */
-extern DECLSPEC void SDLCALL SDL_MemoryBarrierRelease();
-extern DECLSPEC void SDLCALL SDL_MemoryBarrierAcquire();
+#define SDL_MEMORY_BARRIER_USES_FUNCTION
+#define SDL_MemoryBarrierRelease() SDL_MemoryBarrierReleaseFunction()
+#define SDL_MemoryBarrierAcquire() SDL_MemoryBarrierAcquireFunction()
#else
#define SDL_MemoryBarrierRelease() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5" : : "r"(0) : "memory")
#define SDL_MemoryBarrierAcquire() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5" : : "r"(0) : "memory")
#else
#define SDL_MemoryBarrierRelease() __asm__ __volatile__ ("" : : : "memory")
#define SDL_MemoryBarrierAcquire() __asm__ __volatile__ ("" : : : "memory")
+#endif /* __LINUX__ || __ANDROID__ */
#endif /* __GNUC__ && __arm__ */
#else
#if (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x5120))
#include "close_code.h"
-#endif /* _SDL_atomic_h_ */
+#endif /* SDL_atomic_h_ */
/* vi: set ts=4 sw=4 expandtab: */