[clang-tools-extra] [clang-include-fixer] Use heterogenous lookups with std::map (NFC) (PR #115113)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang-tools-extra

Author: Kazu Hirata (kazutakahirata)

<details>
<summary>Changes</summary>

Heterogenous lookups allow us to call find with StringRef, avoiding a
temporary heap allocation of std::string.


---
Full diff: https://github.com/llvm/llvm-project/pull/115113.diff


2 Files Affected:

- (modified) clang-tools-extra/clang-include-fixer/InMemorySymbolIndex.cpp (+1-1) 
- (modified) clang-tools-extra/clang-include-fixer/InMemorySymbolIndex.h (+2-1) 


``````````diff
diff --git a/clang-tools-extra/clang-include-fixer/InMemorySymbolIndex.cpp b/clang-tools-extra/clang-include-fixer/InMemorySymbolIndex.cpp
index 93b534d26f2ce3..6d272af7436923 100644
--- a/clang-tools-extra/clang-include-fixer/InMemorySymbolIndex.cpp
+++ b/clang-tools-extra/clang-include-fixer/InMemorySymbolIndex.cpp
@@ -21,7 +21,7 @@ InMemorySymbolIndex::InMemorySymbolIndex(
 
 std::vector<SymbolAndSignals>
 InMemorySymbolIndex::search(llvm::StringRef Identifier) {
-  auto I = LookupTable.find(std::string(Identifier));
+  auto I = LookupTable.find(Identifier);
   if (I != LookupTable.end())
     return I->second;
   return {};
diff --git a/clang-tools-extra/clang-include-fixer/InMemorySymbolIndex.h b/clang-tools-extra/clang-include-fixer/InMemorySymbolIndex.h
index bea8be91a43c75..c91a7a3a0a10e4 100644
--- a/clang-tools-extra/clang-include-fixer/InMemorySymbolIndex.h
+++ b/clang-tools-extra/clang-include-fixer/InMemorySymbolIndex.h
@@ -27,7 +27,8 @@ class InMemorySymbolIndex : public SymbolIndex {
   search(llvm::StringRef Identifier) override;
 
 private:
-  std::map<std::string, std::vector<find_all_symbols::SymbolAndSignals>>
+  std::map<std::string, std::vector<find_all_symbols::SymbolAndSignals>,
+           std::less<>>
       LookupTable;
 };
 

``````````

</details>


https://github.com/llvm/llvm-project/pull/115113