[llvm] [SandboxIR] Implement SIToFPInst (PR #101374)

[Arthur Eubanks via llvm-commits]

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@@ -1378,6 +1380,27 @@ class CastInst : public Instruction {
 #endif
 };
 
+class SIToFPInst final : public CastInst {
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aeubanks wrote:

I wonder if it's possible to do some CRTP magic to stamp out all of these instantiations much more succinctly. Let me mess around locally.

https://github.com/llvm/llvm-project/pull/101374