[PATCH] D41993: [ELF] - Change shift2 constant of GNU_HASH from 6->11.

George Rimar via llvm-commits llvm-commits at lists.llvm.org
Wed Jan 24 00:07:37 PST 2018


>That's a hypothesis and not a proved theory nor even an observation. I'm sorry but I can't LGTM a performance improvement patch that were

>not backed by a reasonable theory, as it would create a cargo cult.

>
>I spend a few hours to find out why the time to resolve dynamic symbols differs depending on Shift2. It looks like hash values are fairly nicely distributed, and I >couldn't figure out the reason. Unfortunately I don't have enough time to investigate it further at the moment. Maybe we both spent too much time on this.
>
>You could spend more time on this to figure it out, but I guess that this is not the highest priority thing in your todo list. If you want to work on this, you want to take a >look at the dynamic linker and trace it to understand what's going on there. But again I'm not sure if you want to do that now.

Thanks for your time, Rui. I feel the same. It is very interesting to find the reason for me and I think tracing dynamic linker can probably
be a key to solution, though It should be time consuming (it already was) and you right about it is not highest priority atm?.
I'll suspend this patch for now.

George.

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