Member predicate Node::asDefiningArgument

Gets the argument that defines this DefinitionByReferenceNode, if any.

Unlike Node::asDefiningArgument/0, this predicate gets the node representing the value of the index’th indirection after leaving a function. For example, in:

void f(int**);
...
int** x = ...;
f(x);

The node n such that n.asDefiningArgument(1) is the argument x will contain the value of *x after f has returned, and the node n such that n.asDefiningArgument(2) is the argument x will contain the value of **x after the f has returned.