[Mlir-commits] [mlir] [mlir] Apply rule of five for Pass / OperationPass (PR #80998)

[Andrei Golubev]

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@@ -161,6 +161,13 @@ class Pass {
   explicit Pass(TypeID passID, std::optional<StringRef> opName = std::nullopt)
       : passID(passID), opName(opName) {}
   Pass(const Pass &other) : Pass(other.passID, other.opName) {}
+  Pass &operator=(const Pass &other) {
+    this->passID = other.passID;
+    this->opName = other.opName;
+    return *this;
+  }
+  Pass(Pass &&) = delete;
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andrey-golubev wrote:

on further investigation it turns out there's a bunch of not-really-movable members there. also, note that the copy-ctor is *protected*. additionally, there's a [`clone()` method](https://github.com/llvm/llvm-project/blob/ec1fcb381d884ca53e2e0dd4075f946c8f002de2/mlir/include/mlir/Pass/Pass.h#L200) that returns a `unique_ptr`. so, I guess, the expected semantics of the class is to always wrap it into a smart pointer.

thus, i propose we mark all of the special member functions deleted except for the copy-ctor which seems to be used by the clone functionality and call it a day.

https://github.com/llvm/llvm-project/pull/80998