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

[Amir Ayupov via llvm-commits]

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@@ -2041,10 +2041,10 @@ class MCPlusBuilder {
     return InstructionListType();
   }
 
-  virtual InstructionListType createDummyReturnFunction(MCContext *Ctx) const {
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aaupov wrote:

Basically you're moving the definition of `createDummyReturnFunction` from X86 to MCPlusBuilder, right? Please avoid renaming the method (I don't see what's achieved by it), and move the definition here so it's clear why we don't stub it with llvm_unreachable

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