[llvm] 1904241 - [CodeGen] Avoid repeated hash lookups (NFC) (#132658)

[via llvm-commits]

Author: Kazu Hirata
Date: 2025-03-24T07:46:35-07:00
New Revision: 1904241a9ee648b8146576931f2c7d4191054325

URL: https://github.com/llvm/llvm-project/commit/1904241a9ee648b8146576931f2c7d4191054325
DIFF: https://github.com/llvm/llvm-project/commit/1904241a9ee648b8146576931f2c7d4191054325.diff

LOG: [CodeGen] Avoid repeated hash lookups (NFC) (#132658)

Added: 
    

Modified: 
    llvm/lib/CodeGen/WinEHPrepare.cpp

Removed: 
    


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diff  --git a/llvm/lib/CodeGen/WinEHPrepare.cpp b/llvm/lib/CodeGen/WinEHPrepare.cpp
index 37f6726bafca9..74cef6c134736 100644
--- a/llvm/lib/CodeGen/WinEHPrepare.cpp
+++ b/llvm/lib/CodeGen/WinEHPrepare.cpp
@@ -448,11 +448,12 @@ static void calculateCXXStateNumbers(WinEHFuncInfo &FuncInfo,
 
     // It's possible for a cleanup to be visited twice: it might have multiple
     // cleanupret instructions.
-    if (FuncInfo.EHPadStateMap.count(CleanupPad))
+    auto [It, Inserted] = FuncInfo.EHPadStateMap.try_emplace(CleanupPad);
+    if (!Inserted)
       return;
 
     int CleanupState = addUnwindMapEntry(FuncInfo, ParentState, BB);
-    FuncInfo.EHPadStateMap[CleanupPad] = CleanupState;
+    It->second = CleanupState;
     LLVM_DEBUG(dbgs() << "Assigning state #" << CleanupState << " to BB "
                       << BB->getName() << '\n');
     for (const BasicBlock *PredBlock : predecessors(BB)) {
@@ -554,11 +555,12 @@ static void calculateSEHStateNumbers(WinEHFuncInfo &FuncInfo,
 
     // It's possible for a cleanup to be visited twice: it might have multiple
     // cleanupret instructions.
-    if (FuncInfo.EHPadStateMap.count(CleanupPad))
+    auto [It, Inserted] = FuncInfo.EHPadStateMap.try_emplace(CleanupPad);
+    if (!Inserted)
       return;
 
     int CleanupState = addSEHFinally(FuncInfo, ParentState, BB);
-    FuncInfo.EHPadStateMap[CleanupPad] = CleanupState;
+    It->second = CleanupState;
     LLVM_DEBUG(dbgs() << "Assigning state #" << CleanupState << " to BB "
                       << BB->getName() << '\n');
     for (const BasicBlock *PredBlock : predecessors(BB))