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Re: Almost OT, < and <=



> MIPS is different, not using condition codes.  The only pure-comparison
> MIPS operation is <.  (Not <=, not >.)  Anything else you'd have to
> synthesize with a subtraction.
> 
> Beyond cycle counting, I see op< as more primitive than op<=: one
> establishes order, while the other allows for equivalence.  I would
> prefer a SORT which lets me use the most primitive predicate possible.
> On many platforms it won't matter; but on some, it may.
> 
> Enough from me, already.  Let's hear from some other voices.
> 
> Ben
> 
> (P.S. I lied.  One more from me.  Wouldn't using op<= instead of op<
> complicate the implementation of STABLE-SORT? )

But wait a second, isn't

  (< a b) = (not (>= a b)) = (not (<= b a))

at least on integers?

So both < and <= are the **same** machine instruction, except you have
to flip the arguments, and change the destination label, but this has no
run time "cost"...

Marc