[llvm] [SandboxIR] Implement the InsertElementInst class (PR #102404)

[via llvm-commits]

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@@ -753,6 +755,48 @@ class SelectInst : public Instruction {
 #endif
 };
 
+class InsertElementInst final : public Instruction {
+  /// Use Context::createInsertElementInst(). Don't call
+  /// the constructor directly.
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vporpo wrote:

I think we can drop this comment (or make it fit in a single line).

https://github.com/llvm/llvm-project/pull/102404