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Re: gcc compile-time performance


>>>>> Michael Hayes writes:

Michael> Further improvements could be made I believe by better selection of
Michael> the bit set implementation depending on the number and distribution of
Michael> the bits set.  For example, my analysis found that most of the time we
Michael> are dealing with bit sets with one or fewer bits set (CSE in
Michael> particular spends a lot of time hunting the one set bit).

	Which is one of the patches that Daniel Berlin submitted but was
rejected based on the opinion that we wanted fewer, not more, bit set
implementations.  I agree with your and Daniel's goal of using multiple
bit set implementations optimized for different types of uses and
occupancy.

David


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