[Bug tree-optimization/42494] [4.4 Regression] Missed dead-code-elimination

[rguenth at gcc dot gnu dot org]

------- Comment #4 from rguenth at gcc dot gnu dot org  2009-12-30 23:34 -------
The issue is that we do not do predicated value-numbering so we need multiple
invocations of it.  Which all of FRE, DOM and PRE do - but PRE is not run at
-Os in 4.4.

And yes, the optimization done by 4.5 is correct.

You could say "fixed" in 4.5 - or wait for someone to implement predicated
value-numbering to also fix a testcase with one more if (outcnt == 1) func ();


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
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                 CC|                            |matz at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42494