Re: Optimized Cmm containing useless blocks

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" 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 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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