[clang] [NFC][CodeGen] Change CodeGenOpt::Level/CodeGenFileType into enum classes (PR #66295)

[Paul T Robinson via cfe-commits]

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@@ -661,27 +661,27 @@ static bool FixupInvocation(CompilerInvocation &Invocation,
 
 static unsigned getOptimizationLevel(ArgList &Args, InputKind IK,
                                      DiagnosticsEngine &Diags) {
-  unsigned DefaultOpt = llvm::CodeGenOpt::None;
+  unsigned DefaultOpt = 0;
   if ((IK.getLanguage() == Language::OpenCL ||
        IK.getLanguage() == Language::OpenCLCXX) &&
       !Args.hasArg(OPT_cl_opt_disable))
-    DefaultOpt = llvm::CodeGenOpt::Default;
+    DefaultOpt = 2;
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pogo59 wrote:

Actually it looks to me like clang only cares about 0/not-0, and the specific non-zero number is irrelevant. So, internally clang codegen would be better off with a simple Optimize bool. (It looks like LangOpts does it this way already.) CodeGenOpts probably does need to track the actual user-specified level to pass down to LLVM, but it doesn't need it for its own purposes.

https://github.com/llvm/llvm-project/pull/66295