[clang] [CIR] Upstream Re-Throw with no return (PR #154994)

[Andy Kaylor via cfe-commits]

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@@ -3864,4 +3864,63 @@ def CIR_VAArgOp : CIR_Op<"va_arg"> {
   }];
 }
 
+//===----------------------------------------------------------------------===//
+// ThrowOp
+//===----------------------------------------------------------------------===//
+
+def CIR_ThrowOp : CIR_Op<"throw"> {
+  let summary = "(Re)Throws an exception";
+  let description = [{
+    It's equivalent __cxa_throw:
+
+    ```
+    void __cxa_throw(void *thrown_exception, std::type_info *tinfo,
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andykaylor wrote:

I'm not sure this adds any useful information. I'd remove it.

https://github.com/llvm/llvm-project/pull/154994