Fix input-register-conflict checking in native registerizeHarder #3080
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Thanks! Yeah, in C++ it inserts a zero by default. This is one of the things it is easy to mess up when converting between the two languages ;) |
kripken
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Dec 15, 2014
Fix input-register-conflict checking in native registerizeHarder
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This seems to fix the issue mentioned at d8f7e89#commitcomment-8956410, where the native registerizeHarder pass would sometimes use more registers than necessary.
In the js version, the
block->firstKillLoc[name] <= inputDeadLoc[reg]comparison would returnfalsewheninputDeadLockreg]is undefined. AFAICT for the C++ version,inputDeadLoc[reg]will return zero whenregis not in the map, which can cause the comparison to be true. So we should handle missing entries explicitly in this case.(I also fixed some grammar/typos in comments that I noticed while I was in there)