Fix vm

[PalumboN]

Fixing many bugs found running the generated VMs.

• Fix special register allocation for closure creation
• Fix druidExitPoint does not work for meta-compilation of bytecodes #157 (we should keep only one)
• Fix generation of annotateBytecode:
  • Now this logic is only during code generation (no instruction in the CFG), I am not sure about what's better.
    • It adds it after any isMapped trampoline
    • Of if the bytecode is annotated (in the table) there is a check when the generator arrives to the return (for the cases of staged branches)
• There where some problems about IMMUTABILITY and write barrier checks
  • The meta-compilation was generating 2 checks (one for Old Space and other for Perm Space), but both call to the same trampoline. For now I ignored permi from Druid, but we should re-write the interpreter to support both but only call the trampoline once (or maye not.. I'm not sure).
  • I force a IMMUTABILITY := true during code generation, because the code is different and it is a global variable that can have any value.
  • I also changed the order of pops and deoptimization points in the interpreter for better code in Druid

---

We need to merge the PR in the VM before this pharo-project/pharo-vm#880

[guillep]

Loading?

[PalumboN]

Yes, github was slow 👀 Now it is ok.