[llvm] [Utils] Avoid repeated hash lookups (NFC) (PR #136414)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-transforms

Author: Kazu Hirata (kazutakahirata)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/136414.diff


1 Files Affected:

- (modified) llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp (+7-7) 


``````````diff
diff --git a/llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp b/llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp
index 31d8acb706997..fb5e73727b2ef 100644
--- a/llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp
+++ b/llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp
@@ -1633,13 +1633,13 @@ void SCEVExpander::replaceCongruentIVInc(
   // If this phi has the same width but is more canonical, replace the
   // original with it. As part of the "more canonical" determination,
   // respect a prior decision to use an IV chain.
-  if (OrigPhi->getType() == Phi->getType() &&
-      !(ChainedPhis.count(Phi) ||
-        isExpandedAddRecExprPHI(OrigPhi, OrigInc, L)) &&
-      (ChainedPhis.count(Phi) ||
-       isExpandedAddRecExprPHI(Phi, IsomorphicInc, L))) {
-    std::swap(OrigPhi, Phi);
-    std::swap(OrigInc, IsomorphicInc);
+  if (OrigPhi->getType() == Phi->getType()) {
+    bool Chained = ChainedPhis.contains(Phi);
+    if (!(Chained || isExpandedAddRecExprPHI(OrigPhi, OrigInc, L)) &&
+        (Chained || isExpandedAddRecExprPHI(Phi, IsomorphicInc, L))) {
+      std::swap(OrigPhi, Phi);
+      std::swap(OrigInc, IsomorphicInc);
+    }
   }
 
   // Replacing the congruent phi is sufficient because acyclic

``````````

</details>


https://github.com/llvm/llvm-project/pull/136414