[llvm] [LV][NFC] Simplify initialization of MinProfitableTripCount (PR #113445)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-llvm-transforms

@llvm/pr-subscribers-vectorizers

Author: Mel Chen (Mel-Chen)

<details>
<summary>Changes</summary>

Iteration runtime check confirms whether the trip count is greater than VFxUF at least. Therefore, there is no need to adjust the MinProfitableTripCount to VFxUF if it is zero.
Retaining the original MinProfitableTripCount information is also beneficial for supporting more profitable runtime checks in the future.

---
Full diff: https://github.com/llvm/llvm-project/pull/113445.diff


1 Files Affected:

- (modified) llvm/lib/Transforms/Vectorize/LoopVectorize.cpp (+2-6) 


``````````diff
diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 60a94ca1f86e42..804b541e8ffdec 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -469,18 +469,14 @@ class InnerLoopVectorizer {
                       LoopVectorizationCostModel *CM, BlockFrequencyInfo *BFI,
                       ProfileSummaryInfo *PSI, GeneratedRTChecks &RTChecks)
       : OrigLoop(OrigLoop), PSE(PSE), LI(LI), DT(DT), TLI(TLI), TTI(TTI),
-        AC(AC), ORE(ORE), VF(VecWidth), UF(UnrollFactor),
+        AC(AC), ORE(ORE), VF(VecWidth),
+        MinProfitableTripCount(MinProfitableTripCount), UF(UnrollFactor),
         Builder(PSE.getSE()->getContext()), Legal(LVL), Cost(CM), BFI(BFI),
         PSI(PSI), RTChecks(RTChecks) {
     // Query this against the original loop and save it here because the profile
     // of the original loop header may change as the transformation happens.
     OptForSizeBasedOnProfile = llvm::shouldOptimizeForSize(
         OrigLoop->getHeader(), PSI, BFI, PGSOQueryType::IRPass);
-
-    if (MinProfitableTripCount.isZero())
-      this->MinProfitableTripCount = VecWidth;
-    else
-      this->MinProfitableTripCount = MinProfitableTripCount;
   }
 
   virtual ~InnerLoopVectorizer() = default;

``````````

</details>


https://github.com/llvm/llvm-project/pull/113445