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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174028 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/InstructionSimplify.cpp b/lib/Analysis/InstructionSimplify.cpp
index 9f2aa59863f2eacca8232940ba600ec927517a39..18d90b62ce3580d559dbbfc550df42c50068d9e8 100644 (file)
--- a/lib/Analysis/InstructionSimplify.cpp
+++ b/lib/Analysis/InstructionSimplify.cpp
@@ -663,6 +663,10 @@ Value *llvm::SimplifyAddInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW,
 /// accumulates the total constant offset applied in the returned constant. It
 /// returns 0 if V is not a pointer, and returns the constant '0' if there are
 /// no constant offsets applied.
+///
+/// This is very similar to GetPointerBaseWithConstantOffset except it doesn't
+/// follow non-inbounds geps. This allows it to remain usable for icmp ult/etc.
+/// folding.
 static Constant *stripAndComputeConstantOffsets(const DataLayout &TD,
                                                 Value *&V) {
   assert(V->getType()->isPointerTy());