StablePtr / StableName ?

Johannes Waldmann johannes.waldmann at
Tue Jan 24 11:25:54 UTC 2017

Dear Simon,

thanks for looking into this.

> is StableName in the inner loop? 

Yes. This application's inner loop uses a
HashMap (StableName Expression) Int  for memoization.

This is the Tseitin transform: for each node, build a literal.
Each node is stable-named.

I guess the RTS's hashmap performance comes into play
only when pointers are moved (in GC).
The application's hashmap cost will dominate,
because it's used more often.

> You'd have to measure it.

I did. It seems we're good on StableNames, and time goes elsewhere.

- Johannes.

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