[llvm] [SandboxIR] More boilerplate: Function, Argument, Constant, Instruction, OpaqueInst (PR #97343)

[via llvm-commits]

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@@ -59,8 +59,95 @@ void sandboxir::Value::printAsOperandCommon(raw_ostream &OS) const {
     OS << "NULL ";
 }
 
+void sandboxir::Argument::printAsOperand(raw_ostream &OS) const {
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vporpo wrote:

Yeah these can be dropped, let me remove `using namespace llvm` and replace it with `using namespace llvm::sandboxir`.

https://github.com/llvm/llvm-project/pull/97343