[clang] [CIR][OpenMP] Add host op filtering pass to CIR pipeline (PR #209592)

[Jan Leyonberg via cfe-commits]

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@@ -5134,6 +5134,7 @@ void populateCIRToLLVMPasses(mlir::OpPassManager &pm) {
   mlir::populateCIRPreLoweringPasses(pm);
   pm.addPass(mlir::omp::createMarkDeclareTargetPass());
   pm.addPass(createConvertCIRToLLVMPass());
+  pm.addPass(mlir::omp::createHostOpFilteringPass());
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jsjodin wrote:

I turns out this is more complicated than expected since we don't have access to langOpts, and cir-opt would need a flag to enable OpenMP (maybe we want this?) to handle the guards. I will add it to the PR and then we can decide if it is better than just adding the passes.

https://github.com/llvm/llvm-project/pull/209592