Merge branch 'dev' into fsm
add poniters in variables and DFG nodes
add get_driver() to VIdentifier
begin to handle the state transfer graph problem
state_transfer class is ready
need some help from the expression class for state space analysis
in the process of extracting state conditions from expressions
seems I need to rewrite the code
able to break an expression to cases, next, orthogonally extract state from the conditions
doing get_combined_expression
finished get_combined_expression for case, expression and if
add self-loop detection in case and if statements
add combined expression extraction to sequential always blocks
debugging
fixed one bug about generating the combined expression
has a strange segment error to handle
fixed the strange segment error
fixed some bugs
able to report space analysis but only one level
Merge branch 'fsm' into dev