[LV] Adjust comment to say the induction is created in header.

Follow-up suggested post-commit for 1a54889f48fa.

diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index ec95cd6..5dafc56 100644 (file)
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -8448,7 +8448,7 @@ VPValue *VPRecipeBuilder::createBlockInMask(BasicBlock *BB, VPlanPtr &Plan) {
 
     // Introduce the early-exit compare IV <= BTC to form header block mask.
     // This is used instead of IV < TC because TC may wrap, unlike BTC.
-    // Start by constructing the desired canonical IV.
+    // Start by constructing the desired canonical IV in the header block.
     VPValue *IV = nullptr;
     if (Legal->getPrimaryInduction())
       IV = Plan->getOrAddVPValue(Legal->getPrimaryInduction());