[clang] [CIR] Initial implementation of lowering CIR to MLIR (PR #127835)

[Valentin Clement バレンタイン クレメン via cfe-commits]

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@@ -2958,6 +2958,8 @@ defm clangir : BoolFOption<"clangir",
   BothFlags<[], [ClangOption, CC1Option], "">>;
 def emit_cir : Flag<["-"], "emit-cir">, Visibility<[ClangOption, CC1Option]>,
   Group<Action_Group>, HelpText<"Build ASTs and then lower to ClangIR">;
+def emit_cir_mlir : Flag<["-"], "emit-cir-mlir">, Visibility<[CC1Option]>, Group<Action_Group>,
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clementval wrote:

> I think it makes sense to put emit_mlir_EQ in here and then have a separate PR to have flang make use of this option, adding the additional flang dialects, and flang-specific help text.

Yeah we can address that in a follow up PR if it doesn't break flang with this one. 

https://github.com/llvm/llvm-project/pull/127835