Class ControlFlowNode

A control-flow node is either a statement or an expression; in addition, functions are control-flow nodes representing the exit point of the function. The graph represents one possible evaluation order out of all the ones the compiler might have picked.

Control-flow nodes have successors and predecessors at the expression level, so control flow is accurately represented in expressions as well as between statements. Statements and initializers precede their contained expressions, and expressions deeper in the tree precede those higher up; for example, the statement x = y + 1 gets a control-flow graph that looks like

ExprStmt -> y -> 1 -> (+) -> x -> (=)

The first control-flow node in a function is the body of the function (a block), and the last is the function itself, which is used to represent the exit point.

Each throw expression or Handler has a path (along any necessary destructor calls) to its nearest enclosing Handler within the same function, or to the exit point of the function if there is no such Handler. There are no edges from function calls to Handlers.

Import path

import cpp

Direct supertypes

Indirect supertypes

Known direct subtypes

Predicates

getAFalseSuccessor	Gets a node such that the control-flow edge `(this, result)` may be taken when this expression is false.
getAPredecessor	Gets a direct predecessor of this control-flow node, if any.
getASuccessor	Gets a direct successor of this control-flow node, if any.
getATrueSuccessor	Gets a node such that the control-flow edge `(this, result)` may be taken when this expression is true.
getBasicBlock	Gets the `BasicBlock` containing this control-flow node.
getControlFlowScope	Gets the function containing this control-flow node.
getEnclosingStmt	Gets the smallest statement containing this control-flow node.
isCondition	Holds if this node is the top-level expression of a conditional statement, meaning that `this.getATrueSuccessor()` or `this.getAFalseSuccessor()` will have a result.

Inherited predicates

findRootCause	Gets the source of this element: either itself or a macro that expanded to this element.	from Element
fromSource	Holds if this element may be from source. This predicate holds for all elements, except for those in the dummy file, whose name is the empty string. The dummy file contains declarations that are built directly into the compiler.	from Element
getAPrimaryQlClass	Gets the name of a primary CodeQL class to which this element belongs.	from ElementBase
getEnclosingElement	Gets the closest `Element` enclosing this one.	from Element
getFile	Gets the primary file where this element occurs.	from Element
getLocation	Gets the primary location of this element.	from Element
getParentScope	Gets the parent scope of this `Element`, if any. A scope is a `Type` (`Class` / `Enum`), a `Namespace`, a `BlockStmt`, a `Function`, or certain kinds of `Statement`.	from Element
getPrimaryQlClasses	Gets a comma-separated list of the names of the primary CodeQL classes to which this element belongs.	from ElementBase
isAffectedByMacro	Holds if this element is affected in any way by a macro. All elements that are totally or partially generated by a macro are included, so this is a super-set of `isInMacroExpansion`.	from Element
isFromTemplateInstantiation	Holds if this `Element` is a part of a template instantiation (but not the template itself).	from Element
isFromUninstantiatedTemplate	Holds if this `Element` is part of a template `template` (not if it is part of an instantiation of `template`). This means it is represented in the database purely as syntax and without guarantees on the presence or correctness of type-based operations such as implicit conversions.	from Element
isInMacroExpansion	Holds if this element comes from a macro expansion. Only elements that are entirely generated by a macro are included - for elements that partially come from a macro, see `isAffectedByMacro`.	from Element
toString	Gets a textual representation of this element.	from ElementBase