[llvm] [SandboxIR] Implement ConstantFP (PR #106648)

[via llvm-commits]

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@@ -597,6 +598,92 @@ class ConstantInt : public Constant {
 #endif
 };
 
+class ConstantFP final : public Constant {
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vporpo wrote:

We can add it in, I will add a TODO.

https://github.com/llvm/llvm-project/pull/106648