[llvm] [NFC] RuntimeLibcalls: Prefix the impls with 'Impl_' and use an enum class (PR #153850)

[Matt Arsenault via llvm-commits]

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@@ -157,7 +157,7 @@ class RuntimeLibcallImpl {
 
   const Record *getDef() const { return TheDef; }
 
-  StringRef getName() const { return TheDef->getName(); }
+  Twine getName() const { return Twine("Impl_") + TheDef->getName(); }
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arsenm wrote:

Twine should not be returned by value like this. Should keep this returning the original StringRef, and add the prefix at the emission time.

I think the prefix should not be Impl, it's pretty ugly and you end up with multiple adjacent "Impls" in the name.

How about "RTLIB_", "lc_", "libcall_"?



https://github.com/llvm/llvm-project/pull/153850