[clang] [flang] [flang] Implement -mcmodel flag (PR #95411)

[Tom Eccles via cfe-commits]

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@@ -39,6 +39,7 @@ ENUM_CODEGENOPT(RelocationModel, llvm::Reloc::Model, 3, llvm::Reloc::PIC_) ///<
 ENUM_CODEGENOPT(DebugInfo,  llvm::codegenoptions::DebugInfoKind, 4,  llvm::codegenoptions::NoDebugInfo) ///< Level of debug info to generate
 ENUM_CODEGENOPT(VecLib, llvm::driver::VectorLibrary, 3, llvm::driver::VectorLibrary::NoLibrary) ///< Vector functions library to use
 ENUM_CODEGENOPT(FramePointer, llvm::FramePointerKind, 2, llvm::FramePointerKind::None) ///< Enable the usage of frame pointers
+ENUM_CODEGENOPT(CodeModel, llvm::CodeModel::Model, 5, llvm::CodeModel::Model::Small)
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tblah wrote:

I would add it as an `optional` to `CodeGenOptions` in `CodeGenOptions.h`

https://github.com/llvm/llvm-project/pull/95411