[llvm] [BOLT][AArch64] Implemented createDummyReturnFunction. (PR #96626)

[Pavel Samolysov via llvm-commits]

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@@ -1582,6 +1607,12 @@ class AArch64MCPlusBuilder : public MCPlusBuilder {
     return Instrs;
   }
 
+  InstructionListType createDummyReturnFunction(MCContext *Ctx) const override {
+    InstructionListType Insts(1);
+    createReturn(Insts[0]);
+    return Insts;
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samolisov wrote:

I believe, a common implementation of a method in a basic class is a good thing until we mark the method as a pure virtual function (what is not our case). When a new architecture needs a different implementation of the method, it should just override it. I agree, eventually this may lead to a situation where two architectures share the common implementation while many many other do not. A controversial thing.

I agree, a lot of method in the base class here have only some stub implementation with an error reporting and `return false`, this is an approach used trough the whole llvm codebase. It strange a little bit, but I get the goal: just let the developers of particular architectures do not implement all of them.

https://github.com/llvm/llvm-project/pull/96626