[clang][mutation analyzer][NFC] Simplify code in ExprMutationAnalyzer

[steakhal]

No description provided.

[llvmbot]

@llvm/pr-subscribers-clang

@llvm/pr-subscribers-clang-analysis

Author: Balazs Benics (steakhal)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/125283.diff

1 Files Affected:

• (modified) clang/lib/Analysis/ExprMutationAnalyzer.cpp (+1-4)

diff --git a/clang/lib/Analysis/ExprMutationAnalyzer.cpp b/clang/lib/Analysis/ExprMutationAnalyzer.cpp
index d7b44149d0fc4b..93376eb9b93c72 100644
--- a/clang/lib/Analysis/ExprMutationAnalyzer.cpp
+++ b/clang/lib/Analysis/ExprMutationAnalyzer.cpp
@@ -813,10 +813,7 @@ FunctionParmMutationAnalyzer::findMutation(const ParmVarDecl *Parm) {
   // before analyzing parameters of A. Then when analyzing the second "call A",
   // FunctionParmMutationAnalyzer can use this memoized value to avoid infinite
   // recursion.
-  Results[Parm] = nullptr;
-  if (const Stmt *S = BodyAnalyzer.findMutation(Parm))
-    return Results[Parm] = S;
-  return Results[Parm];
+  return Results[Parm] = BodyAnalyzer.findMutation(Parm);
 }
 
 } // namespace clang

[kazutakahirata]

We have the following a few lines above:

  const auto Memoized = Results.find(Parm);
  if (Memoized != Results.end())
    return Memoized->second;

Could we turn that into something like this and use the iterator from try_emplace?

  auto [Memoized, Inserted] = Results.try_emplace(Parm);
  if (!Inserted)
    return Memoized->second;

  Memoized->second = ...;

Maybe we should rename Memorized. The name would sound strange if the insertion is successful.

[steakhal]

Fixed. I usually use "Place" or "Slot" for this.

[kazutakahirata]

LGTM. Thank you for the update!