Static single-assignment form: Difference between revisions

Revision as of 20:56, 15 June 2023

Revision as of 02:57, 7 July 2023

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node 1 strictly dominates 2, 3, and 4, and the immediate predecessorpredecessors of node 4 isare nodes 2 and 3.

Dominance frontiers define the points at which Φ functions are needed. In the above example, when control is passed to node 4, the definition of <code>result</code> used depends on whether control was passed from node 2 or 3. Φ functions are not needed for variables defined in a dominator, as there is only one possible definition that can apply.