On I64 systems, specifies the following application registers: Register Symbol Definition %AR0 . . . Kernel registers %AR7 %AR16 Register Stack Configuration %AR17 Backing Store Pointer %AR18 Backing Store Pointer for Memory Stores %AR19 RSE NaT Collection %AR32 Compare and Exchange Compare Value %AR36 User NaT Collection %AR40 Floating=point Status %AR64 Previous Function State %AR65 Loop Count %AR66 Epilog Count