[clang] [CIR] Record if c++ ABI was overridden via -fc++-abi flag (PR #229494)

[Mariya Podchishchaeva via cfe-commits]

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@@ -257,6 +258,21 @@ cir::CIRDialect::verifyOperationAttribute(mlir::Operation *op,
   if (isOpenCLVersionAttrName(attrName))
     return verifyOpenCLVersionAttr(op, attr);
 
+  if (attrName == getCXXABIAttrName()) {
+    if (!mlir::isa<mlir::ModuleOp>(op))
+      return op->emitOpError() << "expects '" << getCXXABIAttrName()
+                               << "' attribute to be attached to '"
+                               << mlir::ModuleOp::getOperationName() << "'";
+    auto abi = mlir::dyn_cast<mlir::StringAttr>(attr.getValue());
+    if (!abi)
+      return op->emitOpError()
+             << "expects '" << getCXXABIAttrName() << "' to be a string";
+
+    if (!clang::TargetCXXABI::isABI(abi.getValue()))
+      return op->emitOpError() << "unknown C++ ABI '" << abi.getValue() << "'";
+    return success();
+  }
+
----------------
Fznamznon wrote:

Ok, added new verification in 40533b33fb2f7358d032dd141cb971d6321c76d2 . I'm concerned though that this will need updates once more ABIs are supported by CIR.

https://github.com/llvm/llvm-project/pull/229494