Hello, Mikael.
> In this file, we saw that branches are realized by affecting virtually
> an id to each label and use a switch in order to find the right
> target.
Right.
> I want to know if there is another way to do this, for instance, by
> accessing the address of label and to branch directly to it?
As it seems to me, no (I can be mistaken, though).
> In the optimized program (branch_opt.arm), I saw that all branches
> are not suppressed.
> I want to know, if it is possible to suppress the remaining useless
> branches? if yes, how ?
Your switch is too small to emit jump table. LLVM uses some heuristics
in order to emit switches in more-or-less optimal way. The lower number
of cases for jumptable emission is 5. If you'll add one more switch case
to your example, you'll see the jump table emitted.
--
With best regards, Anton Korobeynikov.
Faculty of Mathematics & Mechanics, Saint Petersburg State University.
