atomic: Use DMB ISHLD for aarch64 acquire barrier

This is a little more efficient than a DMB ISH and matches what
GCC, Clang, and MSVC generate for a C++11 acquire fence.
This commit is contained in:
Cameron Gutman
2026-04-23 21:18:05 -05:00
parent c3b0e62850
commit 7751494160

View File

@@ -182,7 +182,7 @@ extern DECLSPEC void SDLCALL SDL_MemoryBarrierAcquireFunction(void);
#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")
#define SDL_MemoryBarrierAcquire() __asm__ __volatile__ ("dmb ishld" : : : "memory")
#elif defined(__GNUC__) && defined(__arm__)
#if 0 /* defined(__LINUX__) || defined(__ANDROID__) */
/* Information from: