[llvm] [SandboxIR] Implement ConstantAggregateZero (PR #107172)

[Sriraman Tallam via llvm-commits]

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@@ -933,6 +935,47 @@ class ConstantVector final : public ConstantAggregate {
   }
 };
 
+class ConstantAggregateZero final : public Constant {
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tmsri wrote:

//TODO: Inherit from ConstantData

https://github.com/llvm/llvm-project/pull/107172