[llvm] r174028 - Add a comment.

[Dan Gohman]

Author: djg
Date: Wed Jan 30 20:45:26 2013
New Revision: 174028

URL: http://llvm.org/viewvc/llvm-project?rev=174028&view=rev
Log:
Add a comment.

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

Modified: llvm/trunk/lib/Analysis/InstructionSimplify.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/InstructionSimplify.cpp?rev=174028&r1=174027&r2=174028&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/InstructionSimplify.cpp (original)
+++ llvm/trunk/lib/Analysis/InstructionSimplify.cpp Wed Jan 30 20:45:26 2013
@@ -663,6 +663,10 @@ Value *llvm::SimplifyAddInst(Value *Op0,
 /// 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());