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

[Sriraman Tallam 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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tmsri wrote:

Why are we not adding ConstantData?  If we are shadowing LLVM IR why not do it rigorously?

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