[PATCH] Expand SimplifyCFG to convert certain simple switches to selects

[Marcello Maggioni]

================
Comment at: lib/Transforms/Utils/SimplifyCFG.cpp:3902
@@ +3901,3 @@
+  // Selects choose between two values only.
+  if (UniqueResults.size() != 2)
+    return false;
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Marcello Maggioni wrote:
> Philip Reames wrote:
> > Since you're handling defaults, wouldn't it also make sense to handle one unique result and a default?  i.e.
> > switch(i) {
> > case 4,5,6: return 5;
> > default: return 0;
> > }
> This is a good idea. I need to check if that is profitable in performance though (needs two comparisons to check if the value falls in the range). If it seems profitable I'll add it.
I actually checked and seems like this specific case is already handled by TurnSwitchRangeIntoICmp()

http://reviews.llvm.org/D4219