[llvm] [SandboxIR] Implement LoadInst (PR #99597)

[Thorsten Schütt via llvm-commits]

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@@ -553,6 +557,50 @@ class Instruction : public sandboxir::User {
 #endif
 };
 
+class LoadInst : public Instruction {
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tschuett wrote:

You can mark `LoadInst` as final for documentation and optimization.

https://github.com/llvm/llvm-project/pull/99597