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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124126 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index e3fcb8428e8252001b9a91b974b341f552f2d1cb..c10af50dd597dd7ac958caf28e7adcf72dae3cd4 100644 (file)
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -3126,6 +3126,7 @@ ScalarEvolution::getUnsignedRange(const SCEV *S) {
 ///
 ConstantRange
 ScalarEvolution::getSignedRange(const SCEV *S) {
+  // See if we've computed this range already.
   DenseMap<const SCEV *, ConstantRange>::iterator I = SignedRanges.find(S);
   if (I != SignedRanges.end())
     return I->second;