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

[Erich Keane via cfe-commits]

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@@ -22,16 +34,156 @@ using namespace llvm;
 namespace cir {
 namespace direct {
 
+struct ConvertCIRToLLVMPass
+    : public mlir::PassWrapper<ConvertCIRToLLVMPass,
+                               mlir::OperationPass<mlir::ModuleOp>> {
+  void getDependentDialects(mlir::DialectRegistry &registry) const override {
+    registry.insert<mlir::BuiltinDialect, mlir::DLTIDialect,
+                    mlir::LLVM::LLVMDialect, mlir::func::FuncDialect>();
+  }
+  void runOnOperation() final;
+
+  StringRef getDescription() const override {
+    return "Convert the prepared CIR dialect module to LLVM dialect";
+  }
+
+  StringRef getArgument() const override { return "cir-flat-to-llvm"; }
+};
+
+// This pass requires the CIR to be in a "flat" state. All blocks in each
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erichkeane wrote:

Would love more detail here, but I'm not knowledgable enough to review the text, so Bruno or Nathan can approve whatever they think is sufficiently descriptive.

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