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Re: 100x -O0 Compile Time Regression {3.2,3.3} -> {3.4,3.5}


On Feb 13, 2004, at 6:20 AM, Zdenek Dvorak wrote:
-
+  free_dominance_info (CDI_DOMINATORS);
    FOR_ALL_BB (bb)
      {
        for (e = bb->succ; e ; e = e->succ_next)


This looks OK, provided it bootstraps, etc.

Daniel, could you please also measure compile time on some less
artificial examples than 20001226-1.c before commiting this patch? It
adds one unnecessary recount of whole dominator tree, so it might
be that it would not be win on usual functions not countaining thousands
of critical edges.


If it showed up to be case, something would have to be done about
updating dominators in split_edge to avoid the quadratic behavior it
exhibits on this testcase.

Or perhaps we could just check the number of edges before deciding whether to do this?


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