1 files changed, 128 insertions, 7 deletions

diff --git a/core/safe_refcount.h b/core/safe_refcount.h
index 802d84cccc..39967d5ac4 100644
--- a/core/safe_refcount.h
+++ b/core/safe_refcount.h
@@ -36,20 +36,141 @@
 #include "platform_config.h"
 #include "typedefs.h"
 
-uint32_t atomic_conditional_increment(register uint32_t *counter);
+// Atomic functions, these are used for multithread safe reference counters!
+
+#ifdef NO_THREADS
+
+/* Bogus implementation unaware of multiprocessing */
+
+template <class T>
+static _ALWAYS_INLINE_ T atomic_conditional_increment(register T *pw) {
+
+	if (*pw == 0)
+		return 0;
+
+	(*pw)++;
+
+	return *pw;
+}
+
+template <class T>
+static _ALWAYS_INLINE_ T atomic_decrement(register T *pw) {
+
+	(*pw)--;
+
+	return *pw;
+}
+
+template <class T>
+static _ALWAYS_INLINE_ T atomic_increment(register T *pw) {
+
+	(*pw)++;
+
+	return *pw;
+}
+
+template <class T, class V>
+static _ALWAYS_INLINE_ T atomic_sub(register T *pw, register V val) {
+
+	(*pw) -= val;
+
+	return *pw;
+}
+
+template <class T, class V>
+static _ALWAYS_INLINE_ T atomic_add(register T *pw, register V val) {
+
+	(*pw) += val;
+
+	return *pw;
+}
+
+template <class T, class V>
+static _ALWAYS_INLINE_ T atomic_exchange_if_greater(register T *pw, register V val) {
+
+	if (val > *pw)
+		*pw = val;
+
+	return *pw;
+}
+
+#elif defined(__GNUC__)
+
+/* Implementation for GCC & Clang */
+
+// GCC guarantees atomic intrinsics for sizes of 1, 2, 4 and 8 bytes.
+// Clang states it supports GCC atomic builtins.
+
+template <class T>
+static _ALWAYS_INLINE_ T atomic_conditional_increment(register T *pw) {
+
+	while (true) {
+		T tmp = static_cast<T const volatile &>(*pw);
+		if (tmp == 0)
+			return 0; // if zero, can't add to it anymore
+		if (__sync_val_compare_and_swap(pw, tmp, tmp + 1) == tmp)
+			return tmp + 1;
+	}
+}
+
+template <class T>
+static _ALWAYS_INLINE_ T atomic_decrement(register T *pw) {
+
+	return __sync_sub_and_fetch(pw, 1);
+}
+
+template <class T>
+static _ALWAYS_INLINE_ T atomic_increment(register T *pw) {
+
+	return __sync_add_and_fetch(pw, 1);
+}
+
+template <class T, class V>
+static _ALWAYS_INLINE_ T atomic_sub(register T *pw, register V val) {
+
+	return __sync_sub_and_fetch(pw, val);
+}
+
+template <class T, class V>
+static _ALWAYS_INLINE_ T atomic_add(register T *pw, register V val) {
+
+	return __sync_add_and_fetch(pw, val);
+}
+
+template <class T, class V>
+static _ALWAYS_INLINE_ T atomic_exchange_if_greater(register T *pw, register V val) {
+
+	while (true) {
+		T tmp = static_cast<T const volatile &>(*pw);
+		if (tmp >= val)
+			return tmp; // already greater, or equal
+		if (__sync_val_compare_and_swap(pw, tmp, val) == tmp)
+			return val;
+	}
+}
+
+#elif defined(_MSC_VER)
+// For MSVC use a separate compilation unit to prevent windows.h from polluting
+// the global namespace.
+uint32_t atomic_conditional_increment(register uint32_t *pw);
 uint32_t atomic_decrement(register uint32_t *pw);
 uint32_t atomic_increment(register uint32_t *pw);
 uint32_t atomic_sub(register uint32_t *pw, register uint32_t val);
 uint32_t atomic_add(register uint32_t *pw, register uint32_t val);
 uint32_t atomic_exchange_if_greater(register uint32_t *pw, register uint32_t val);
 
-uint64_t atomic_conditional_increment(register uint64_t *counter);
+uint64_t atomic_conditional_increment(register uint64_t *pw);
 uint64_t atomic_decrement(register uint64_t *pw);
 uint64_t atomic_increment(register uint64_t *pw);
 uint64_t atomic_sub(register uint64_t *pw, register uint64_t val);
 uint64_t atomic_add(register uint64_t *pw, register uint64_t val);
 uint64_t atomic_exchange_if_greater(register uint64_t *pw, register uint64_t val);
 
+#else
+//no threads supported?
+#error Must provide atomic functions for this platform or compiler!
+#endif
+
 struct SafeRefCount {
 
 	uint32_t count;
@@ -57,17 +178,17 @@ struct SafeRefCount {
 public:
 	// destroy() is called when weak_count_ drops to zero.
 
-	bool ref() { //true on success
+	_ALWAYS_INLINE_ bool ref() { //true on success
 
 		return atomic_conditional_increment(&count) != 0;
 	}
 
-	uint32_t refval() { //true on success
+	_ALWAYS_INLINE_ uint32_t refval() { //true on success
 
 		return atomic_conditional_increment(&count);
 	}
 
-	bool unref() { // true if must be disposed of
+	_ALWAYS_INLINE_ bool unref() { // true if must be disposed of
 
 		if (atomic_decrement(&count) == 0) {
 			return true;
@@ -76,12 +197,12 @@ public:
 		return false;
 	}
 
-	uint32_t get() const { // nothrow
+	_ALWAYS_INLINE_ uint32_t get() const { // nothrow
 
 		return count;
 	}
 
-	void init(uint32_t p_value = 1) {
+	_ALWAYS_INLINE_ void init(uint32_t p_value = 1) {
 
 		count = p_value;
 	}