Re: arm: Only load TLS values when needed

[Jonathan Austin]

Hi AndrÃ,

On 14/08/13 15:07, Andrà Hentschel wrote:
> Hi Jonathan,
> Any updates on this?

I was holding out to see the version with ldrd at the top, as discussed 
below - I never saw a version with that change? I'd meant to ping you to 
see if that was coming, sorry.


[...]
> > > [...]
> > > > > Now we've only got one instruction between the store and the load
> > > > > and risk stalling the pipeline...
> > > > >
> > > > > Dave M cautiously says "The ancient advice was that one instruction
> > > > > was enough" but this is very core dependent... I wonder if anyone
> > > > > has a good idea about whether this is an issue here...?
> > > >
> > > > We could use a ldrd at the top, that'd be nearly what we have right
> > > > now, don't we?
> > >
> > > Yea, that'd be good - as far as I can see from an 1136 TRM, the ldrd *may* be two cycles (depending on alignment of the words) but the ldr and ldrne will always be two cycles. Ahhh, the joys of modifying the fast path ;)

Was expecting to see something that reflected this discussion,

Jonny

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