c9642cf7af
Added an API for creating signals with attributes. Added two APIs for IPC operations on signals. Initial use of exceptions for error handling. Add ref counting to signals. Removed spin loops from signal destructors. Signals are no longer to be destroyed with delete, use DeleteSignal instead. Added delete safety to doorbells. Added secondary hsa_signal_t -> Signal* translation path for IPC enabled signals. Change-Id: Id59065d002f0c2566b0a9425694da2ed27cb7d7f