XCSG:ControlFlow (Edge)

Specification

Metaclass	ControlFlow (Edge)
Extends	Edge
Description	Links Statements to other statements that follow them in the program order of a Function declaration. Multiple edges from the same statement indicate branching of control flow.

Direct Subkinds	ControlFlowBackEdge

It is worth noting that control flow edges do not guarantee actual order of execution, as both compilers and CPUs are free to re-order the execution of statements that do not have data interdependence, unless some kind of synchronization command is used to prevent such optimizations. While the re-ordering is always equivalent to the original ordering if the program is single-threaded, the re-ordering may be noticed by other threads, or occasionally in otherwise single-threaded programs which access data mutated by other programs or by hardware (if, for example, two requests for the current time were run out-of-order).

However, where questions regarding the ordering of actions that have data interdependence might arise from analyzing data flow alone, the program ordering information from control flow can be used to disambiguate.