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#
# Patch managed by http://www.holgerschurig.de/patcher.html
#
--- /dev/null
+++ qt-embedded-opensource-4.0.0-b1/src/core/arch/arm/qatomic.cpp
@@ -0,0 +1,64 @@
+#include <qhash.h>
+
+#define UNLOCKED {-1,-1,-1,-1}
+#define UNLOCKED2 UNLOCKED,UNLOCKED
+#define UNLOCKED4 UNLOCKED2,UNLOCKED2
+#define UNLOCKED8 UNLOCKED4,UNLOCKED4
+#define UNLOCKED16 UNLOCKED8,UNLOCKED8
+#define UNLOCKED32 UNLOCKED16,UNLOCKED16
+#define UNLOCKED64 UNLOCKED32,UNLOCKED32
+#define UNLOCKED128 UNLOCKED64,UNLOCKED64
+#define UNLOCKED256 UNLOCKED128,UNLOCKED128
+
+// use a 4k page for locks
+static int locks[256][4] = { UNLOCKED256 };
+
+int *getLock(volatile void *addr)
+{ return locks[qHash(const_cast<void *>(addr)) % 256]; }
+
+static int *align16(int *lock)
+{
+ ulong off = (((ulong) lock) % 16);
+ return off ? (int *)(ulong(lock) + 16 - off) : lock;
+}
+
+extern "C" {
+
+ int q_ldcw(volatile int *addr);
+
+ void q_atomic_lock(int *lock)
+ {
+ // ldcw requires a 16-byte aligned address
+ volatile int *x = align16(lock);
+ // FIXME WHERE IS q_ldcw ??? while (q_ldcw(x) == 0)
+ ;
+ }
+
+ void q_atomic_unlock(int *lock)
+ { lock[0] = lock[1] = lock[2] = lock[3] = -1; }
+
+ int q_atomic_test_and_set_ptr(volatile void *ptr, void *expected, void *newval)
+ {
+ int *lock = getLock(ptr);
+ q_atomic_lock(lock);
+ if (*reinterpret_cast<void * volatile *>(ptr) == expected) {
+ *reinterpret_cast<void * volatile *>(ptr) = newval;
+ q_atomic_unlock(lock);
+ return 1;
+ }
+ q_atomic_unlock(lock);
+ return 0;
+ }
+
+ void *q_atomic_set_ptr(volatile void *ptr, void *newval)
+ {
+ int *lock = getLock(ptr);
+ q_atomic_lock(lock);
+ void *oldval = *reinterpret_cast<void * volatile *>(ptr);
+ *reinterpret_cast<void * volatile *>(ptr) = newval;
+ q_atomic_unlock(lock);
+ return oldval;
+ }
+
+}
+
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