[clang] [CIR] Upstream TypeInfo attribute (PR #159426)

[Henrich Lauko via cfe-commits]

================
@@ -521,6 +522,20 @@ mlir::Value CIRAttrToValue::visitCirAttr(cir::GlobalViewAttr globalAttr) {
   llvm_unreachable("Expecting pointer or integer type for GlobalViewAttr");
 }
 
+// TypeInfoAttr visitor.
+mlir::Value CIRAttrToValue::visitCirAttr(cir::TypeInfoAttr typeinfoArr) {
+  mlir::Type llvmTy = converter->convertType(typeinfoArr.getType());
+  mlir::Location loc = parentOp->getLoc();
+  mlir::Value result = rewriter.create<mlir::LLVM::UndefOp>(loc, llvmTy);
+
+  for (auto [idx, elt] : llvm::enumerate(typeinfoArr.getData())) {
+    mlir::Value init = visit(elt);
+    result = rewriter.create<mlir::LLVM::InsertValueOp>(loc, result, init, idx);
----------------
xlauko wrote:

```suggestion
    result = mlir::LLVM::InsertValueOp::create(rewriter, loc, result, init, idx);
```

https://github.com/llvm/llvm-project/pull/159426