Branch Prediction?

[Andrew Haley]

On 11/20/2014 02:28 PM, Paul Hohensee wrote:
> If it were me (and it's not :) ), I'd want to see some generated code
> examples that would benefit.  Perhaps quantify the benefit by getting a
> libjvm profile, look at the code for the top 10 or 20 methods, reorganize
> it via a proof-of-concept implementation and measure the result.  I'd also
> take into consideration that future hardware improvements (e.g., larger
> icache line size) might negate any current improvement, so it'd have to be
> a 'big' benefit.  Again if it were me (and it's not :) ), it would take
> maybe a per-instance 10% improvement before I'd accept the intellectual
> overhead cost of a permanent implementation. I worry a lot about long term
> source code maintainability, hence I have a sort of automatic skepticism
> about features than complicate it. :)

I agree, but:

The problem with the "benchamrk and see" approach is that a fast
system is made up of many very small optimizations, each one of which
may be lost in the noise.

Andrew.