[Bug target/58405] Unoptimal code generated for computed goto

[gjl at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58405

Georg-Johann Lay <gjl at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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             Status|WAITING                     |RESOLVED
         Resolution|---                         |WORKSFORME

--- Comment #3 from Georg-Johann Lay <gjl at gcc dot gnu.org> ---
(In reply to semicontinuity from comment #2)
> Now I cannot reproduce that as well..
> It seems that I've compiled it with -ffixed-r30 -ffixed-r31 (different from
> original intention) - in this case it produces this kind of assembly .

I can reproduce it with -ffixed-r30 -ffixed-r31.  But as I already wrote above,
without Z (R30/R31) you cannot no more write sensible programs -- except
completely trivial ones. I don't think it makes sense to put effort into
optimizing useless programs or for programs that very likely will break by
occupying Z.

> Still, the code could be more optimal, without rjmp, push/pop - just with
> ijmp replaced by 2 pushes + ret.

Without -ffixed*, the code /does/ use IJMP.  If you take away Z, it's not
possible to use IJMP, of course.