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Re: [PATCH] Eliminates phi on branch for CMP result


On Sun, May 12, 2019 at 10:07:28PM -0500, Jiufu Guo wrote:
> To elimiate the instructions which moving result of CMP to GPR, I'm
> wondering maybe we could do a combine(or a peephole) after bbro to let
> the condition jump directly using the result of CMP.

It will have to be a peephole.  And peepholes are machine-specific.

You will also not get any further optimisations in those blocks, that way;
not combine etc.

It really should be done on gimple, not rtl.


Segher


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