Re: [patch 0/2] Immediate Values - jump patching update

[H. Peter Anvin]

Mathieu Desnoyers wrote:
> Following your own suggestion, why don't we fix gcc and make it
> interleave unlikely blocks less heavily with hot blocks ?

Doing this with compiler support is definitely The Right Thing, so I 
think this is the best way.

> > Furthermore, modern CPUs often speculatively fetch *both* 
> > branches of a conditional.
> >
> > This is actually the biggest motivation for patching static branches.
>
> Agreed. I'd like to find some info about which microarchitectures you
> have in mind. Intel Core 2 ?

Not sure about Core 2, although Core 2 definitely can track down the 
wrong branch on a mispredict.

> Let's fix gcc ! ;)

Sounds great :)

	-hpa

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