Seems like something that should be delegated to a peep hole optimizer. What you describe make it possible to reorder the basic blocks at a later stage.

Alexander

On Mar 8, 2014 9:24 AM, "Johan Tibell" <johan.tibell@gmail.com> wrote:
On a related note, doesn't Cmm support fall-through branches? Heap checks use two branches instead of one branch and one fall-through case:

      c1Cq:
          Hp = Hp + 152;
          if (Hp > I64[BaseReg + 856]) goto c1Cs; else goto c1Cr;
      c1Cs:
          I64[BaseReg + 904] = 152;
          goto c1Cp;
      c1Cp:
          R1 = PicBaseReg + a_r1za_closure;
          call (I64[BaseReg - 8])(R1) args: 8, res: 0, upd: 8;
      c1Cr:



On Sat, Mar 8, 2014 at 9:21 AM, Johan Tibell <johan.tibell@gmail.com> wrote:
While looking at some generated Cmm I saw things like this

c1Cm:
    goto c1Cq;
c1Cq:

i.e. useless basic blocks that haven't been optimized away. Is this to be expected?

-- Johan



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