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Re: [patch] e500 port

Aldy Hernandez wrote:
> 
> > You need to add a case PROCESSOR_PPC8540 for MULT to the RTX_COSTS macro
> > in rs6000.h otherwise RTX_COSTS is returing a bogus value.
> 
> Hmm.  Good catch.
> 
> Vlad, do you know what cost is for the e500?
> 
  MULT for e500 has 4 cycles latency time.  Although I am a bit
skeptical that the cost should be the latency time.  It was right for
non pipelined architectures.  Sometimes issue the long latency time
(pipelined) insn may be a win.  In general, to solve the problem code
selection should be integrated with insn scheduling.

Vlad
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