The v6m ISA has no way to express a CAS loop natively without turning off the interrupts or using the kernel cmpxchg harness. On such a platform the user has to provide a few __sync_* builtins to satisfy the linker.
The v6m ISA has no way to express a CAS loop natively without turning off the interrupts or using the kernel cmpxchg harness. On such a platform the user has to provide a few __sync_* builtins to satisfy the linker.