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Re: Fwd: [PATCH] Scheduling result adjustment to enable macro-fusion


> 
> I am not sure if AMD hardware has any limitations here.  It fuses only cmp/test

This is what Agner Fog says:

A CMP or TEST instruction immediately followed by a conditional jump can be
fused into a single macro-op. This applies to all versions of the CMP and TEST
instructions and all conditional jumps except if the CMP or TEST has a
rip-relative address or both a displacement and an immediate operand. 

So it is a bit more weird.  Perhaps you can extend your predicate to look
for IP relative addresses & displacements of CMP and TEST, too.

Honza
> as far as I know, but I do not think it matters what flags you use.
> 
> The i386 specific part of the change seems resonable to me.
> 
> Honza


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