that would turn out to be safe. Moreover, they ignore the fact that coalescing may even improve the colorability of the graph by reducing the degree of neighbor nodes that are interfering with both the source and target nodes being coalesced. This paper proposes a new heuristic called optimistic coalescing

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the colorability of the graph; d) optimistic coalescing coalesces moves aggressively, then gives up about as few moves as possible so that the graph becomes colorable again. We almost completely classify the NP-completeness of these problems, discussing also on the structure of the interference graph: arbitrary

during SSA construction, instances of the coalescing problem under SSA have fewer affinities than traditional methods. This paper presents Optimistic Chordal Coloring (OCC), a coalescing heuristic for chordal graphs. OCC was evaluated on interference graphs from embedded/multimedia benchmarks: in all

Optimistic coalescing has been proven as an elegant and effective technique that provides better chances of safely coloring more registers in register allocation than other coalescing techniques. Its algorithm originally assumes homogeneous registers, which are all gathered in the same register

This paper presents a new register assignment heuristic for procedures in SSA Form, whose interference graphs are chordal; the heuristic is called optimistic chordal coloring (OCC). Previous register assignment heuristics eliminate copy instructions via coalescing, in other words, merging nodes

A computer simulation study has been made of the accuracy of estimates of H 5 4N e l from a sample from a single isolated population of finite size. The accuracies turn out to be well predicted by a formula developed by Fu and Li, who used optimistic assumptions. Their formulas are restated

previous ILP-based approaches to register allocation. We then show a variant of Park and Moon's optimistic coalescing algorithm that does a very good (though not provably optimal) job of remov-ing the register-register moves. The result is Pentium code that is 9.5 % faster than code generated by SSA

The aim of this paper is two-fold; first, we develop an interprocedural register allocation algorithm, an extended variant of Briggs' optimistic graph colouring. We use interprocedural coalescing as an elegant way to achieve a custom-made calling convention for each function. We add a

-02. We account for the uncertainties due to the propagation in the Galaxy and to the uncertain details of the coalescence process, and we consider the constraints already imposed by anti-proton searches. We find that only for very optimistic configurations it might be possible to achieve detection