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Most hash tables are power-of-two sized so that they can use masking for the access. It looks like the�bounds check doesn't get eliminated, although it could be.
Based on the�equivalence�
a\[x & (a.length - 1)\]�throws if and only if�a.length == 0, I'm proposing this simple algorithm:- For each array access, check if the index has been computed via a bitwise and.
- If so, check if either of the operands was computed as length minus one.
- If so, replace the bounds check by a zero-length check.
This zero-length check can then be easily moved out of the loop by the existing optimizations.
I hope I'm not talking non-sense. For more details see�
Regards,
Martin.