[llvm] r176214 - The FastISEL should be fast. But when we record statistics we use atomic operations to increment the counters.

[Eli Bendersky]

>> > It's why I was asking, I think it might be an interesting idea to put
>> > all
>> > the statistics
>> > behind NDEBUG so we can feel free to collect stats whenever rather than
>> > needing to worry about putting the high firing status under NDEBUG
>> > explicitly.
>>
>> FWIW, I'm +1 on this. You'll still have to wrap the actual ++counter
>> code with DEBUG or some other macro-fu all over the code, though.
>>
>> Eil
>
>
>
> Perhaps we could just re-define the operator++(), operator--(), etc. in
> Statistics.h to only do real work "#if !defined(NDEBUG) ||
> defined(LLVM_ENABLE_STATS)", and to be nops otherwise.  Where
> LLVM_ENABLE_STATS would be like LLVM_ENABLE_DUMP...   If that sounds
> reasonable, I could spin up a patch.

+1. I like the idea of also having LLVM_ENABLE_STATS, so that if
anyone for some reason wants these stats for a release build, that
becomes possible too.

Eli