Optimized Cmm containing useless blocks

Jan Stolarek jan.stolarek at p.lodz.pl
Sun Mar 9 21:22:20 UTC 2014

> useless basic blocks that haven't been optimized away. Is this to be
> expected?
I believe this should not happen but it's hard to say without looking at a complete dump. Could 
you post full Cmm dump + a minimial working example that generates that? 

> On a related note, doesn't Cmm support fall-through branches? 
Cmm program is represented as a graph with each node (a block of code) having explicit list of 
successors. Having fall-throughs in Cmm would require storing blocks linearily with a guarantee 
that their order will not change. Note that fall-throughs are present in the generated assembly. 


More information about the ghc-devs mailing list