[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.
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aeubanks wrote:

typo

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