[llvm] Add StringMap::lookup() overload to take a default value and return a reference to the value to avoid a copy (PR #115469)

[via llvm-commits]

github-actions[bot] wrote:

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:warning: C/C++ code formatter, clang-format found issues in your code. :warning:

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git-clang-format --diff 31af00fda73df8e85e30c71f66e096d486ec8c8b 468007d5bdcaf4308697dce682a4454c970272d9 --extensions h,cpp -- llvm/include/llvm/ADT/StringMap.h llvm/lib/CodeGen/MachineOutliner.cpp llvm/tools/llvm-rc/ResourceScriptStmt.cpp llvm/unittests/ADT/StringMapTest.cpp
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View the diff from clang-format here.
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``````````diff
diff --git a/llvm/include/llvm/ADT/StringMap.h b/llvm/include/llvm/ADT/StringMap.h
index be57cce851..0c3e30fa00 100644
--- a/llvm/include/llvm/ADT/StringMap.h
+++ b/llvm/include/llvm/ADT/StringMap.h
@@ -259,7 +259,7 @@ public:
 
   /// lookup - Return the entry for the specified key, or a default
   /// provided value if no such entry exists.
-  const ValueTy &lookup(StringRef Key, const ValueTy& Value) const {
+  const ValueTy &lookup(StringRef Key, const ValueTy &Value) const {
     const_iterator Iter = find(Key);
     if (Iter != end())
       return Iter->second;

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https://github.com/llvm/llvm-project/pull/115469