[llvm-dev] (RFC) Encoding code duplication factor in discriminator

[Robinson, Paul via llvm-dev]

The largest discriminator is 779 (coming from 471.omnetpp, which has significant amount of EH code.)

779 distinct blocks coming from a single source location?  That's astounding.

Or something like:
high bits   ---------->  low bits
EEEEEEEECCCCCFFDDD CFFFDDD CCFFFDD

So the lower 7 bits should be able to cover 85% percentile and the lower 14 bits should be able to cover 99% percentile.

Having a scheme for compact representation for the vast majority of cases is great, and will really help keep the size of the section under control.  Did you have a plan for the degenerate cases where one of these elements (D/F/C) exceeds the specified capacity?  You already have one, because 779 > 8 bits.
Thanks,
--paulr

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