[llvm] 606ff7e - [Utils] Avoid repeated hash lookups (NFC) (#127171)

[via llvm-commits]

Author: Kazu Hirata
Date: 2025-02-14T01:34:54-08:00
New Revision: 606ff7ea9b29f93e536b13c83dc24de6b8a4e8cd

URL: https://github.com/llvm/llvm-project/commit/606ff7ea9b29f93e536b13c83dc24de6b8a4e8cd
DIFF: https://github.com/llvm/llvm-project/commit/606ff7ea9b29f93e536b13c83dc24de6b8a4e8cd.diff

LOG: [Utils] Avoid repeated hash lookups (NFC) (#127171)

Added: 
    

Modified: 
    llvm/lib/Transforms/Utils/LoopUnrollAndJam.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Utils/LoopUnrollAndJam.cpp b/llvm/lib/Transforms/Utils/LoopUnrollAndJam.cpp
index 89cfee2acd82c..054b0ba2ba664 100644
--- a/llvm/lib/Transforms/Utils/LoopUnrollAndJam.cpp
+++ b/llvm/lib/Transforms/Utils/LoopUnrollAndJam.cpp
@@ -395,8 +395,9 @@ llvm::UnrollAndJamLoop(Loop *L, unsigned Count, unsigned TripCount,
       }
 
       // Update our running maps of newest clones
-      PrevItValueMap[New] = (It == 1 ? *BB : LastValueMap[*BB]);
-      LastValueMap[*BB] = New;
+      auto &Last = LastValueMap[*BB];
+      PrevItValueMap[New] = (It == 1 ? *BB : Last);
+      Last = New;
       for (ValueToValueMapTy::iterator VI = VMap.begin(), VE = VMap.end();
            VI != VE; ++VI) {
         PrevItValueMap[VI->second] =