WinRT: merged with SDL 2.0.0 codebase (aka. SDL hg rev d6a8fa507a45)

src/atomic/SDL_atomic.c

@@ -29,8 +29,8 @@
 */
 #undef SDL_AtomicCAS
 #undef SDL_AtomicCASPtr
- 
-/* 
+
+/*
   If any of the operations are not provided then we must emulate some
   of them. That means we need a nice implementation of spin locks
   that avoids the "one big lock" problem. We use a vector of spin
@@ -40,7 +40,7 @@
   To generate the index of the lock we first shift by 3 bits to get
   rid on the zero bits that result from 32 and 64 bit allignment of
   data. We then mask off all but 5 bits and use those 5 bits as an
-  index into the table. 
+  index into the table.
 
   Picking the lock this way insures that accesses to the same data at
   the same time will go to the same lock. OTOH, accesses to different
@@ -101,4 +101,18 @@ SDL_AtomicCASPtr(void **a, void *oldval, void *newval)
     return retval;
 }
 
+#if defined(__GNUC__) && defined(__arm__) && \
+   (defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6T2__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__))
+__asm__(
+"   .align 2\n"
+"   .globl _SDL_MemoryBarrierRelease\n"
+"   .globl _SDL_MemoryBarrierAcquire\n"
+"_SDL_MemoryBarrierRelease:\n"
+"_SDL_MemoryBarrierAcquire:\n"
+"   mov r0, #0\n"
+"   mcr p15, 0, r0, c7, c10, 5\n"
+"   bx lr\n"
+);
+#endif /* __GNUC__ && __arm__ && ARMV6 */
+
 /* vi: set ts=4 sw=4 expandtab: */

src/atomic/SDL_spinlock.c

@@ -76,11 +76,11 @@ SDL_AtomicTryLock(SDL_SpinLock *lock)
     return (result == 0);
 
 #elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
-	int result;
-	__asm__ __volatile__(
+    int result;
+    __asm__ __volatile__(
         "lock ; xchgl %0, (%1)\n"
         : "=r" (result) : "r" (lock), "0" (1) : "cc", "memory");
-	return (result == 0);
+    return (result == 0);
 
 #elif defined(__MACOSX__) || defined(__IPHONEOS__)
     /* Maybe used for PowerPC, but the Intel asm or gcc atomics are favored. */
@@ -114,10 +114,10 @@ SDL_AtomicUnlock(SDL_SpinLock *lock)
 
 #elif HAVE_GCC_ATOMICS || HAVE_GCC_SYNC_LOCK_TEST_AND_SET
     __sync_lock_release(lock);
-    
+
 #elif HAVE_PTHREAD_SPINLOCK
     pthread_spin_unlock(lock);
-	
+
 #else
     *lock = 0;
 #endif