Optimize gen_statem engine loop

* Use synchronolus cancel_timer since that is more efficient
  than asynchronous when a process cancels its own timer
* Restructure the state to have fewer fields by breaking
  out practically constant fields into a separate
  loop argument record #params{}, group state and data
  into one field and dito for timer fields
* Optimize engine loop arguments for staying in the loop so
  the detour to sys:handle_system_message/6 will require
  packing/unpacking of the sys: state, and of the argument Parent
* Avoid double reverse of event queue in many cases
* Restructure the state transition to not have duplicate
  tracks for sys_debug and non-sys_debug cases
* Shortcut the empty list case where possible
* Loop unroll reversal of up to 2-element lists to avoid calling
  lists:reverse/2 since an external call spills all live
  registers to the stack
* Bring out the callback mode check to the engine loop

0 files changed, 0 insertions, 0 deletions