[clang] [OpenACC][CIR] Implement 'atomic capture' lowering (PR #168422)

[Henrich Lauko via cfe-commits]

================
@@ -314,15 +314,80 @@ const VarDecl *getLValueDecl(const Expr *e) {
   return cast<VarDecl>(dre->getDecl());
 }
 
-mlir::LogicalResult
-CIRGenFunction::emitOpenACCAtomicConstruct(const OpenACCAtomicConstruct &s) {
-  // For now, we are only support 'read'/'write'/'update', so diagnose. We can
-  // switch on the kind later once we implement the 'capture' form.
-  if (s.getAtomicKind() == OpenACCAtomicKind::Capture) {
-    cgm.errorNYI(s.getSourceRange(), "OpenACC Atomic Construct");
-    return mlir::failure();
+static mlir::acc::AtomicReadOp
+emitAtomicRead(CIRGenFunction &cgf, CIRGenBuilderTy &builder,
+               mlir::Location start,
+               OpenACCAtomicConstruct::SingleStmtInfo inf) {
----------------
xlauko wrote:

```suggestion
               const OpenACCAtomicConstruct::SingleStmtInfo &inf) {
```
?

https://github.com/llvm/llvm-project/pull/168422