Member predicate SsaVariable::getPredecessorBlockForPhiArgument

Gets the edge(s) (result->this.getDefinition()) on which the SSA variable ‘input’ defines this SSA variable. For each incoming edge X->B, where B is the basic block containing this phi-node, only one of the input SSA variables for this phi-node is live. This predicate returns the predecessor block such that the variable ‘input’ is the live variable on the edge result->B.