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On Mon, 2 Mar 2009, Adam Nemet wrote:
> > Let's face it -- it's not the instruction list which is inadequate. It
> > is the decision to make $gp call-clobbered for o32 which was suboptimal.
> > There was a reason it got fixed with the advent of the new ABIs (along
> > with a number of other issues).
>
> AIUI, the problem exists with the new ABIs as well. You either ensure that
> the GOT pointer is live at each branch pessimizing the code or you need a
> different way of fetching the destination address into a register.
Well, $gp is call-saved with the new ABIs and given the other eight
static registers there is little point in clobbering $gp once it has been
set up in the prologue. Too much hassle for too little gain IMO.
MAciej
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