[llvm-commits] [llvm] r111145 - /llvm/trunk/lib/Analysis/ScalarEvolution.cpp

[Dan Gohman]

Author: djg
Date: Mon Aug 16 11:31:39 2010
New Revision: 111145

URL: http://llvm.org/viewvc/llvm-project?rev=111145&view=rev
Log:
Add a comment.

Modified:
    llvm/trunk/lib/Analysis/ScalarEvolution.cpp

Modified: llvm/trunk/lib/Analysis/ScalarEvolution.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ScalarEvolution.cpp?rev=111145&r1=111144&r2=111145&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/ScalarEvolution.cpp (original)
+++ llvm/trunk/lib/Analysis/ScalarEvolution.cpp Mon Aug 16 11:31:39 2010
@@ -2468,6 +2468,11 @@
   std::map<SCEVCallbackVH, const SCEV *>::const_iterator I = Scalars.find(V);
   if (I != Scalars.end()) return I->second;
   const SCEV *S = createSCEV(V);
+
+  // The process of creating a SCEV for V may have caused other SCEVs
+  // to have been created, so it's necessary to insert the new entry
+  // from scratch, rather than trying to remember the insert position
+  // above.
   Scalars.insert(std::make_pair(SCEVCallbackVH(V, this), S));
   return S;
 }