[clang] [CIR] Build out AST consumer patterns to reach the entry point into CIRGen (PR #91007)

[Erich Keane via cfe-commits]

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@@ -42,6 +47,14 @@ CreateFrontendBaseAction(CompilerInstance &CI) {
   StringRef Action("unknown");
   (void)Action;
 
+  auto UseCIR = CI.getFrontendOpts().UseClangIRPipeline;
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erichkeane wrote:

Thats a question I think for @AaronBallman .  This DOES live in the 'clang' directory, so I would think this should all follow the Clang coding standards, but I can see the justification for using the MLIR standard, same as the capitalization (@lanza ).  

There WAS some discussion elsewhere, but I cant find the thread, so I dont know what was agreed upon.

https://github.com/llvm/llvm-project/pull/91007