[patch] Fix recent breakage in basic-block.h

Jan Hubicka jh@suse.cz
Wed Sep 19 05:37:00 GMT 2001


> DCE=Dead-Code Elimination?  Does it really make sense so early in the
> process?  AFAIU the tree optimizations are done before the RTL ones
> and DCE should be one of the later optimizations.  What kind of
> benefits do you expect?
Some of side effect from RTL generation are unavoidable.  For instance
if you force local array on the stack, it remains there even if all
references to it has been eliminated.  Elliminating dead code earlier will
avoid this, should speed up compiler (as RTL generation is relativly expensive
and a lot of code tends to be dead in some cases) and makes possible other
optimizations, as if you don't know what is dead, you can't optimize very
well.

Honza
> 
> Andreas
> -- 
>  Andreas Jaeger
>   SuSE Labs aj@suse.de
>    private aj@arthur.inka.de
>     http://www.suse.de/~aj



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