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.