Lab4: Implement basic scalar optimizations and lower Phi nodes to assembly

src/ir/IRPrinter.cpp

@@ -103,6 +103,8 @@ static std::string OpcodeToString(Opcode op) {
       return "sitofp";
     case Opcode::FPToSI:
       return "fptosi";
+    case Opcode::Phi:
+      return "phi";
   }
   return "?";
 }
@@ -347,6 +349,16 @@ void IRPrinter::Print(const Module& module, std::ostream& os) {
                << TypeToString(*cast->GetType()) << "\n";
             break;
           }
+          case Opcode::Phi: {
+            auto* phi = static_cast<const PhiInst*>(inst);
+            os << "  %" << phi->GetName() << " = phi " << TypeToString(*phi->GetType()) << " ";
+            for (size_t i = 0; i < phi->GetNumIncoming(); ++i) {
+              if (i > 0) os << ", ";
+              os << "[ " << ValueToString(phi->GetIncomingValue(i)) << ", %" << phi->GetIncomingBlock(i)->GetName() << " ]";
+            }
+            os << "\n";
+            break;
+          }
         }
       }
     }