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

[Mats Petersson 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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Leporacanthicus wrote:

Rightly or wrongly, I've changed it to copy the way that Clang does it, and store the string in CodeGenOptions, then parse it (twice, but sharing the code to do so, rather than implementing the same-ish code twice in Clang). 

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