[llvm] [SandboxIR] Adds BasicBlock and adds functionality to Function and Context (PR #97637)

[Arthur Eubanks via llvm-commits]

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@@ -278,12 +381,55 @@ class Context {
   DenseMap<llvm::Value *, std::unique_ptr<sandboxir::Value>>
       LLVMValueToValueMap;
 
+  /// Take ownership of VPtr and store it in `LLVMValueToValueMap`.
+  Value *registerValue(std::unique_ptr<Value> &&VPtr);
+
+  /// Helper for avoiding recursion loop when creating SBConstants.
+  SmallDenseSet<llvm::Constant *, 8> VisitedConstants;
+
+  Value *getOrCreateValueInternal(llvm::Value *V, int Depth,
+                                  llvm::User *U = nullptr);
+
+  template <typename SBT, typename LLVMT>
+  SBT *getOrCreateGeneric(LLVMT *LLVMV) {
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aeubanks wrote:

is the constructor of SBT always going to take `(LLVMT, Context)` as the arguments? e.g. LLVM Values have different constructor param lists so it doesn't make sense to templatize these sorts of builders in that context (pun intended)

https://github.com/llvm/llvm-project/pull/97637