Merge pull request JetBrains#108 from udalov/kt2423

KT-2423 Jump after condition check in inner loop is to the wrong label

Author: alextkachman

compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java

@@ -285,21 +285,16 @@ public StackValue visitWhileExpression(JetWhileExpression expression, StackValue
         Label condition = new Label();
         v.mark(condition);
 
-        Label end = continueLabel != null ? continueLabel : new Label();
+        Label end = new Label();
         blockStackElements.push(new LoopBlockStackElement(end, condition, targetLabel(expression)));
 
-        Label savedContinueLabel = continueLabel;
-        continueLabel = condition;
-
         final StackValue conditionValue = gen(expression.getCondition());
         conditionValue.condJump(end, true, v);
 
         gen(expression.getBody(), Type.VOID_TYPE);
         v.goTo(condition);
 
-        continueLabel = savedContinueLabel;
-        if (end != continueLabel)
-            v.mark(end);
+        v.mark(end);
 
         blockStackElements.pop();
 
@@ -683,14 +678,13 @@ else if (stackElement instanceof LoopBlockStackElement) {
     }
 
     private StackValue generateSingleBranchIf(StackValue condition, JetExpression expression, boolean inverse) {
-        Label end = continueLabel != null ? continueLabel : new Label();
+        Label end = new Label();
 
         condition.condJump(end, inverse, v);
 
         gen(expression, Type.VOID_TYPE);
 
-        if (continueLabel != end)
-            v.mark(end);
+        v.mark(end);
         return StackValue.none();
     }
 
@@ -849,8 +843,6 @@ public StackValue visitObjectLiteralExpression(JetObjectLiteralExpression expres
         return StackValue.onStack(closure.getClassname().getAsmType());
     }
 
-    private Label continueLabel;
-    
     private StackValue generateBlock(List<JetElement> statements) {
         Label blockStart = new Label();
         v.mark(blockStart);
@@ -880,12 +872,9 @@ private StackValue generateBlock(List<JetElement> statements) {
         }
 
         StackValue answer = StackValue.none();
-        Label savedContinueLabel = continueLabel;
-        continueLabel = null;
         for (int i = 0, statementsSize = statements.size(); i < statementsSize; i++) {
             JetElement statement = statements.get(i);
             if (i == statements.size() - 1 /*&& statement instanceof JetExpression && !bindingContext.get(BindingContext.STATEMENT, statement)*/) {
-                continueLabel = savedContinueLabel;
                 answer = gen(statement);
             }
             else {
@@ -2709,9 +2698,6 @@ public StackValue visitTryExpression(JetTryExpression expression, StackValue rec
 The "returned" value of try expression with no finally is either the last expression in the try block or the last expression in the catch block
 (or blocks).
          */
-        Label savedContinueLabel = continueLabel;
-        continueLabel = null;
-
         JetFinallySection finallyBlock = expression.getFinallyBlock();
         if (finallyBlock != null) {
             blockStackElements.push(new FinallyBlockStackElement(expression));
@@ -2771,8 +2757,6 @@ public StackValue visitTryExpression(JetTryExpression expression, StackValue rec
             blockStackElements.pop();
         }
 
-        continueLabel = savedContinueLabel;
-
         return StackValue.onStack(expectedAsmType);
     }
 

compiler/testData/codegen/regressions/kt2423.kt

@@ -0,0 +1,46 @@
+fun ok1(): Boolean {
+    val queue = linkedList(1, 2, 3)
+    while (!queue.isEmpty()) {
+        queue.poll()
+        for (y in 1..3) {
+            if (queue.contains(y)) {
+                return true
+            }
+        }
+    }
+    return false
+}
+
+fun ok2(): Boolean {
+    val queue = linkedList(1, 2, 3)
+    val array = array(1, 2, 3)
+    while (!queue.isEmpty()) {
+        queue.poll()
+        for (y in array) {
+            if (queue.contains(y)) {
+                return true
+            }
+        }
+    }
+    return false
+}
+
+fun ok3(): Boolean {
+    val queue = linkedList(1, 2, 3)
+    while (!queue.isEmpty()) {
+        queue.poll()
+        var x = 0
+        do {
+            x++
+            if (x == 2) return true
+        } while (x < 2)
+    }
+    return false
+}
+
+fun box(): String {
+    if (!ok1()) return "Fail #1"
+    if (!ok2()) return "Fail #2"
+    if (!ok3()) return "Fail #3"
+    return "OK"
+}

compiler/tests/org/jetbrains/jet/codegen/ControlStructuresTest.java

@@ -361,4 +361,9 @@ public void testKt1688() {
         createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
         blackBoxFile("regressions/kt1688.kt");
     }
+
+    public void testKt2423() {
+        createEnvironmentWithFullJdk();
+        blackBoxFile("regressions/kt2423.kt");
+    }
 }