Cycles: Move utility atomics function to util_atomic.h

No functional changes, just better to keep all atomic function in a single place,
they might become handy later.

1 files changed, 32 insertions, 0 deletions

diff --git a/intern/cycles/util/util_atomic.h b/intern/cycles/util/util_atomic.h
index fa0d35e1034..85a82d38275 100644
--- a/intern/cycles/util/util_atomic.h
+++ b/intern/cycles/util/util_atomic.h
@@ -17,6 +17,8 @@
 #ifndef __UTIL_ATOMIC_H__
 #define __UTIL_ATOMIC_H__
 
+#ifndef __KERNEL_GPU__
+
 /* Using atomic ops header from Blender. */
 #include "atomic_ops.h"
 
@@ -30,4 +32,34 @@ ATOMIC_INLINE void atomic_update_max_z(size_t *maximum_value, size_t value)
 	}
 }
 
+#else  /* __KERNEL_GPU__ */
+
+#ifdef __KERNEL_OPENCL__
+
+/* Float atomics implementation credits:
+ *   http://suhorukov.blogspot.in/2011/12/opencl-11-atomic-operations-on-floating.html
+ */
+ccl_device_inline void atomic_add_float(volatile ccl_global float *source,
+                                        const float operand)
+{
+	union {
+		unsigned int int_value;
+		float float_value;
+	} new_value;
+	union {
+		unsigned int int_value;
+		float float_value;
+	} prev_value;
+	do {
+		prev_value.float_value = *source;
+		new_value.float_value = prev_value.float_value + operand;
+	} while (atomic_cmpxchg((volatile ccl_global unsigned int *)source,
+	                        prev_value.int_value,
+	                        new_value.int_value) != prev_value.int_value);
+}
+
+#endif  /* __KERNEL_OPENCL__ */
+
+#endif  /* __KERNEL_GPU__ */
+
 #endif /* __UTIL_ATOMIC_H__ */