[Bug rtl-optimization/15242] [3.3/3.4 regression] pessimization of "goto *"

steven at gcc dot gnu dot org gcc-bugzilla@gcc.gnu.org
Thu Mar 10 12:48:00 GMT 2005

------- Additional Comments From steven at gcc dot gnu dot org  2005-03-10 12:48 -------
> Maybe there should be another combining pass after the duplication
> of the indirect jumps.  Should I create another PR for this?

There should not be another "combining" pass (you really mean constant
propagation).  This new unfactoring stuff runs after register allocation,
so such a pass would not really help, except maybe to make the code look
prettier to you.

But, is this:

        mov    0xfffffffc(%ebx),%eax
        jmp    *%eax

slower than this:

        jmp    *0xfffffffc(%ebx)

or have you not tried that (e.g. by hacking the assembly by hand)?



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