Homework B (benchmarks)

src/cd/transform/optimizers/UnusedClassRemoval.java

@@ -0,0 +1,38 @@
+package cd.transform.optimizers;
+
+import cd.ir.Ast.ClassDecl;
+import cd.ir.Symbol.ArrayTypeSymbol;
+import cd.ir.Symbol.TypeSymbol;
+import cd.transform.analysis.ClassUsage;
+
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+public class UnusedClassRemoval extends GlobalOptimizerVisitor<Void> {
+	public boolean go(List<ClassDecl> classDecls, List<TypeSymbol> typeList) {
+		Set<ClassDecl> used = new ClassUsage().go(classDecls);
+		Set<ClassDecl> toRemove = new HashSet<>(classDecls);
+		toRemove.removeAll(used);
+
+		// Remove classes from list of declarations
+		classDecls.clear();
+		classDecls.addAll(used);
+
+		// Remove corresponding types and array types
+		for (ClassDecl classDecl : toRemove) {
+			typeList.remove(classDecl.sym);
+			TypeSymbol arrayType = null;
+			for (TypeSymbol type : typeList) {
+				if (type instanceof ArrayTypeSymbol && ((ArrayTypeSymbol) type).elementType == classDecl.sym) {
+					arrayType = type;
+					break;
+				}
+			}
+			assert arrayType != null;
+			typeList.remove(arrayType);
+		}
+
+		return !toRemove.isEmpty();
+	}
+}