[llvm] [SandboxIR] Adds BasicBlock and adds functionality to Function and Context (PR #97637)

[Arthur Eubanks via llvm-commits]

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@@ -231,6 +283,8 @@ class Instruction : public sandboxir::User {
     return OS;
   }
 #endif
+  /// This is used by BasicBlcok::iterator.
+  virtual unsigned getNumOfIRInstrs() const = 0;
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aeubanks wrote:

virtual methods seem weird for a core class, but I suppose we can always refactor later if it turns out to be an issue (e.g. for compile times)

https://github.com/llvm/llvm-project/pull/97637