[llvm] [SandboxIR] IR Tracker (PR #99238)

[Arthur Eubanks via llvm-commits]

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@@ -630,6 +632,8 @@ class BasicBlock : public Value {
 class Context {
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aeubanks wrote:

should we split out some of these into their own headers? e.g. LLVMContext is its own header, Value, then various instructions are grouped together

https://github.com/llvm/llvm-project/pull/99238