pass A1 tests with naive implement.

Author: 1475505

A1/tai-e/src/main/java/pascal/taie/analysis/dataflow/analysis/LiveVariableAnalysis.java

@@ -25,6 +25,8 @@
 import pascal.taie.analysis.dataflow.fact.SetFact;
 import pascal.taie.analysis.graph.cfg.CFG;
 import pascal.taie.config.AnalysisConfig;
+import pascal.taie.ir.exp.LValue;
+import pascal.taie.ir.exp.RValue;
 import pascal.taie.ir.exp.Var;
 import pascal.taie.ir.stmt.Stmt;
 
@@ -48,23 +50,44 @@ public boolean isForward() {
     @Override
     public SetFact<Var> newBoundaryFact(CFG<Stmt> cfg) {
         // TODO - finish me
-        return null;
+        return new SetFact<Var>();
     }
 
     @Override
     public SetFact<Var> newInitialFact() {
         // TODO - finish me
-        return null;
+        return new SetFact<Var>();
     }
 
     @Override
     public void meetInto(SetFact<Var> fact, SetFact<Var> target) {
         // TODO - finish me
+        target.union(fact);
     }
 
     @Override
     public boolean transferNode(Stmt stmt, SetFact<Var> in, SetFact<Var> out) {
         // TODO - finish me
-        return false;
+        var old_in = new SetFact<Var>();
+        old_in.set(in);
+        var use = stmt.getUses();
+        var def = stmt.getDef();
+        for (RValue val : use){
+            if (val instanceof Var){
+                in.add((Var)val);
+            }
+        }
+        if (def.isPresent()) {
+            var val = def.get();
+            if (val instanceof Var) {
+                SetFact<Var> tmp = new SetFact<>();
+                tmp.set(out);
+                tmp.remove((Var) val);
+                in.union(tmp);
+                return !in.equals(old_in);
+            }
+        }
+        in.union(out);
+        return !in.equals(old_in);
     }
 }

A1/tai-e/src/main/java/pascal/taie/analysis/dataflow/solver/IterativeSolver.java

@@ -40,5 +40,22 @@ protected void doSolveForward(CFG<Node> cfg, DataflowResult<Node, Fact> result)
     @Override
     protected void doSolveBackward(CFG<Node> cfg, DataflowResult<Node, Fact> result) {
         // TODO - finish me
+        // int rounds = 0;
+        boolean changed = true;
+        while (changed) {
+            // System.out.println("Round: " + rounds); rounds++;
+            changed = false;
+            for (Node node : cfg){
+                if (node == cfg.getExit()){
+                    continue;
+                }
+                for (Node n : cfg.getSuccsOf(node)) {
+                    analysis.meetInto(result.getInFact(n), result.getOutFact(node));
+                }
+                if (analysis.transferNode(node, result.getInFact(node), result.getOutFact(node))){
+                    changed = true;
+                }
+            }
+        }
     }
 }

A1/tai-e/src/main/java/pascal/taie/analysis/dataflow/solver/Solver.java

@@ -82,6 +82,12 @@ protected void initializeForward(CFG<Node> cfg, DataflowResult<Node, Fact> resul
 
     protected void initializeBackward(CFG<Node> cfg, DataflowResult<Node, Fact> result) {
         // TODO - finish me
+        result.setInFact(cfg.getExit(), analysis.newBoundaryFact(cfg));
+        for (Node node : cfg){
+            result.setInFact(node, analysis.newInitialFact());
+            // 为了实现 meet 策略，需要在初始化阶段给每条语句的 OUT[S] 赋上和 IN[S] 一样的初值。
+            result.setOutFact(node, analysis.newInitialFact());
+        }
     }
 
     /**

Test/src/remove_set.java

@@ -0,0 +1,17 @@
+package src;
+
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * @author ll （ created: 2022-09-17 14:07 )
+ */
+public class remove_set {
+    public static void main(String[] args){
+        var a = new HashSet<Integer>();
+        a.add(1);
+        a.add(2);
+        var b = a.remove(1);
+        System.out.println(a);
+    }
+}