[llvm] [SandboxIR] Implement PHINodes (PR #101111)

[via llvm-commits]

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@@ -1290,6 +1292,97 @@ class GetElementPtrInst final : public Instruction {
 #endif
 };
 
+class PHINode final : public Instruction {
+  /// Use Context::createPHINode(). Don't call the
+  /// constructor directly.
+  PHINode(llvm::PHINode *PHI, Context &Ctx)
+      : Instruction(ClassID::PHI, Opcode::PHI, PHI, Ctx) {}
+  friend Context; // for SBPHINode()
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vporpo wrote:

SBPHINode -> PHINode

https://github.com/llvm/llvm-project/pull/101111