[clang] [CIR] Initial implementation of CIR-to-LLVM IR lowering pass (PR #125260)

[Nathan Lanza via cfe-commits]

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@@ -31,6 +33,24 @@ namespace direct {
 std::unique_ptr<llvm::Module>
 lowerDirectlyFromCIRToLLVMIR(mlir::ModuleOp mlirModule,
                              llvm::LLVMContext &llvmCtx);
+
+class CIRToLLVMGlobalOpLowering
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lanza wrote:

This is originally in `clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.h`. Any reason you're promoting it to the `include` top level dir? 

https://github.com/llvm/llvm-project/pull/125260