Branch/jump target prediction -8

By: Etienne (etienne_lorrain.delete@this.yahoo.fr), August 19, 2016 12:25 am
Room: Moderated Discussions
Maynard Handley (name99.delete@this.name99.org) on August 18, 2016 10:02 am wrote:
> What provides more value is fixing the remaining problems
> in this fetch pipeline. These might include things like

Wouldn't it be worthwhile, because it seems technology has reach a point where fetching those "unit of code" (i.e. assembly instructions) very optimised, to make more work in each "unit of code" (so they can take more time to do more usefull stuff).
Obviously it would not be with the same assembly instruction set, but if you had integer operations with saturation (could also be programmable saturation at for instance [0..4095]), integer division with round-up, round-down and round nearest - then the compiler would not need to generate so many simple assembly instructions with so many jumps, which seems so difficult to fetch.

Also, if I may, more general question (obviously I am not in a domain when out-of-order execution is the rule):
Nowadays on standard/personal computers, which kind of OOO level is available, how may assembly instructions can be waiting in the dispatcher?
What are the code constructs to avoid to keep OOO execution happy?

Thanks,
Etienne.
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                    The (apparent) state of trace caches on modern CPUsMaynard Handley2016/08/23 06:48 AM
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                      The (wrong) state of trace caches on modern CPUsEric Bron2016/08/25 06:12 AM
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                          The (wrong) state of trace caches on modern CPUsExophase2016/08/25 10:32 AM
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                          The (wrong) state of trace caches on modern CPUsMaynard Handley2016/08/25 11:01 AM
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