[clang] [CIR][OpenMP] Enable lowering of the OpenMP dialect to LLVM IR (PR #178515)

[Jan Leyonberg via cfe-commits]

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@@ -149,9 +149,7 @@ void CIRGenerator::HandleTagDeclDefinition(TagDecl *d) {
   // inline initializers as definitions.
   if (astContext->getTargetInfo().getCXXABI().isMicrosoft())
     cgm->errorNYI(d->getSourceRange(), "HandleTagDeclDefinition: MSABI");
-  // For OpenMP emit declare reduction functions, if required.
-  if (astContext->getLangOpts().OpenMP)
-    cgm->errorNYI(d->getSourceRange(), "HandleTagDeclDefinition: OpenMP");
+  // TODO(OMP): For OpenMP emit declare reduction functions, if required.
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jsjodin wrote:

I didn't quite answer your question about ignoring things here. Declare reduction relies on the reduction clause which isn't supported and will give an error before this becomes usable. However it is probably best to give an error here in case the code contains a declare reduction, even if it would generate dead code. 

https://github.com/llvm/llvm-project/pull/178515