[llvm] r304597 - FunctionAttrs: Skip it if the effective SCC (ignoring optnone functions) is empty

[David Blaikie via llvm-commits]

Author: dblaikie
Date: Fri Jun  2 16:24:17 2017
New Revision: 304597

URL: http://llvm.org/viewvc/llvm-project?rev=304597&view=rev
Log:
FunctionAttrs: Skip it if the effective SCC (ignoring optnone functions) is empty

Minor optimization but mostly simplifies my debugging so I'm not dealing
with empty SCCNodeSets while investigating issues in this optimization.

Modified:
    llvm/trunk/lib/Transforms/IPO/FunctionAttrs.cpp

Modified: llvm/trunk/lib/Transforms/IPO/FunctionAttrs.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/FunctionAttrs.cpp?rev=304597&r1=304596&r2=304597&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/IPO/FunctionAttrs.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/FunctionAttrs.cpp Fri Jun  2 16:24:17 2017
@@ -1188,6 +1188,10 @@ static bool runImpl(CallGraphSCC &SCC, A
     SCCNodes.insert(F);
   }
 
+  // Skip it if the SCC only contains optnone functions.
+  if (SCCNodes.empty())
+    return Changed;
+
   Changed |= addArgumentReturnedAttrs(SCCNodes);
   Changed |= addReadAttrs(SCCNodes, AARGetter);
   Changed |= addArgumentAttrs(SCCNodes);