[llvm] [DebugInfo] Avoid repeated hash lookups (NFC) (PR #128632)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-debuginfo

Author: Kazu Hirata (kazutakahirata)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/128632.diff


1 Files Affected:

- (modified) llvm/lib/DebugInfo/LogicalView/Readers/LVCodeViewReader.cpp (+1-2) 


``````````diff
diff --git a/llvm/lib/DebugInfo/LogicalView/Readers/LVCodeViewReader.cpp b/llvm/lib/DebugInfo/LogicalView/Readers/LVCodeViewReader.cpp
index 6ce9bcbeb13c0..8074f1a9fddfb 100644
--- a/llvm/lib/DebugInfo/LogicalView/Readers/LVCodeViewReader.cpp
+++ b/llvm/lib/DebugInfo/LogicalView/Readers/LVCodeViewReader.cpp
@@ -721,12 +721,11 @@ Error LVCodeViewReader::traverseSymbolSection(StringRef SectionName,
                                    getFileName());
 
         LLVM_DEBUG({ W.printString("Symbol Name", SymbolName); });
-        if (FunctionLineTables.count(SymbolName) != 0) {
+        if (!FunctionLineTables.try_emplace(SymbolName, Contents).second) {
           // Saw debug info for this function already?
           return createStringError(object_error::parse_failed, getFileName());
         }
 
-        FunctionLineTables[SymbolName] = Contents;
         SymbolNames.push_back(SymbolName);
       }
       break;

``````````

</details>


https://github.com/llvm/llvm-project/pull/128632