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File: life
This phase is a preliminary to Pack. It involves three passes: – A pre-pass that computes the DEF and USE sets for live TN analysis, while also assigning local TN numbers, splitting blocks if necessary. ### But not really... – A flow analysis pass that does backward flow analysis on the component to find the live TNs at each block boundary. – A post-pass that finds the conflict set for each TN.
#| Exploit the fact that a single VOP can only exhaust LTN numbers when there are large more operands. Since more operand reference cannot be interleaved with temporary reference, the references all effectively occur at the same time. This means that we can assign all the more args and all the more results the same LTN number and the same lifetime info. |#