[clang] [Clang] Improve ``-Wtautological-overlap-compare`` diagnostics flag (PR #133653)

[Yutong Zhu via cfe-commits]

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@@ -70,13 +70,11 @@ static SourceLocation GetEndLoc(Decl *D) {
   return D->getLocation();
 }
 
-/// Returns true on constant values based around a single IntegerLiteral.
-/// Allow for use of parentheses, integer casts, and negative signs.
-/// FIXME: it would be good to unify this function with
-/// getIntegerLiteralSubexpressionValue at some point given the similarity
-/// between the functions.
+/// Returns true on constant values based around a single IntegerLiteral,
+/// CharacterLiteral, or FloatingLiteral. Allow for use of parentheses, integer
+/// casts, and negative signs.
 
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YutongZhuu wrote:

No, I think my change would probably cause this function to be more diverged from ``getIntegerLiteralSubexpressionValue``, so I think generalizing them into one function isn't a good idea anymore.

https://github.com/llvm/llvm-project/pull/133653