ARCH_rtx_costs

[Shinpei Kato]

Hi, Eric. Thanks for reply.

> http://gcc.gnu.org/onlinedocs/gccint/Costs.html#Costs

Yes I refer to it.

> Has most of the cost information you need, looking at a similar existing
> port could help.  What you want to remember in particular is that it's a
> set of relative costs. For example, if your "fast" instruction is an
> add, e.g. add $2, $3, $4, and takes one cycle and a multiply takes 12
> cycles then you'd want to have a MULT cost COST_N_INSNS (12).

So COST_N_INSNS doesn't mean real cycles but relative cycles, does it?
That is, COST_N_INSNS (1) doesn't mean one cycle.
If I don't know about cycle cost, I need to ask people who develop an
architecture.
Is my understanding correct?

Regards,
Shinpei Kato