7167125: Two variables after the same operation in a inner class return different results

Reviewed-by: jjg, mcimadamore

src/share/classes/com/sun/tools/javac/comp/Lower.java

@@ -3066,55 +3066,38 @@ public class Lower extends TreeTranslator {
     }
 
     public void visitAssignop(final JCAssignOp tree) {
-        if (!tree.lhs.type.isPrimitive() &&
-            tree.operator.type.getReturnType().isPrimitive()) {
-            // boxing required; need to rewrite as x = (unbox typeof x)(x op y);
-            // or if x == (typeof x)z then z = (unbox typeof x)((typeof x)z op y)
-            // (but without recomputing x)
-            JCTree newTree = abstractLval(tree.lhs, new TreeBuilder() {
-                    public JCTree build(final JCTree lhs) {
-                        JCTree.Tag newTag = tree.getTag().noAssignOp();
-                        // Erasure (TransTypes) can change the type of
-                        // tree.lhs.  However, we can still get the
-                        // unerased type of tree.lhs as it is stored
-                        // in tree.type in Attr.
-                        Symbol newOperator = rs.resolveBinaryOperator(tree.pos(),
-                                                                      newTag,
-                                                                      attrEnv,
-                                                                      tree.type,
-                                                                      tree.rhs.type);
-                        JCExpression expr = (JCExpression)lhs;
-                        if (expr.type != tree.type)
-                            expr = make.TypeCast(tree.type, expr);
-                        JCBinary opResult = make.Binary(newTag, expr, tree.rhs);
-                        opResult.operator = newOperator;
-                        opResult.type = newOperator.type.getReturnType();
-                        JCTypeCast newRhs = make.TypeCast(types.unboxedType(tree.type),
-                                                          opResult);
-                        return make.Assign((JCExpression)lhs, newRhs).setType(tree.type);
-                    }
-                });
-            result = translate(newTree);
-            return;
-        }
-        tree.lhs = translate(tree.lhs, tree);
-        tree.rhs = translate(tree.rhs, tree.operator.type.getParameterTypes().tail.head);
-
-        // If translated left hand side is an Apply, we are
-        // seeing an access method invocation. In this case, append
-        // right hand side as last argument of the access method.
-        if (tree.lhs.hasTag(APPLY)) {
-            JCMethodInvocation app = (JCMethodInvocation)tree.lhs;
-            // if operation is a += on strings,
-            // make sure to convert argument to string
-            JCExpression rhs = (((OperatorSymbol)tree.operator).opcode == string_add)
-              ? makeString(tree.rhs)
-              : tree.rhs;
-            app.args = List.of(rhs).prependList(app.args);
-            result = app;
-        } else {
-            result = tree;
-        }
+        final boolean boxingReq = !tree.lhs.type.isPrimitive() &&
+            tree.operator.type.getReturnType().isPrimitive();
+
+        // boxing required; need to rewrite as x = (unbox typeof x)(x op y);
+        // or if x == (typeof x)z then z = (unbox typeof x)((typeof x)z op y)
+        // (but without recomputing x)
+        JCTree newTree = abstractLval(tree.lhs, new TreeBuilder() {
+                public JCTree build(final JCTree lhs) {
+                    JCTree.Tag newTag = tree.getTag().noAssignOp();
+                    // Erasure (TransTypes) can change the type of
+                    // tree.lhs.  However, we can still get the
+                    // unerased type of tree.lhs as it is stored
+                    // in tree.type in Attr.
+                    Symbol newOperator = rs.resolveBinaryOperator(tree.pos(),
+                                                                  newTag,
+                                                                  attrEnv,
+                                                                  tree.type,
+                                                                  tree.rhs.type);
+                    JCExpression expr = (JCExpression)lhs;
+                    if (expr.type != tree.type)
+                        expr = make.TypeCast(tree.type, expr);
+                    JCBinary opResult = make.Binary(newTag, expr, tree.rhs);
+                    opResult.operator = newOperator;
+                    opResult.type = newOperator.type.getReturnType();
+                    JCExpression newRhs = boxingReq ?
+                            make.TypeCast(types.unboxedType(tree.type),
+                                                      opResult) :
+                            opResult;
+                    return make.Assign((JCExpression)lhs, newRhs).setType(tree.type);
+                }
+            });
+        result = translate(newTree);
     }
 
     /** Lower a tree of the form e++ or e-- where e is an object type */

test/tools/javac/7167125/DiffResultAfterSameOperationInnerClasses.java

+/*
+ * Copyright (c) 2002, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 7167125
+ * @summary Two variables after the same operation in a inner class return
+ * different results
+ * @run main DiffResultAfterSameOperationInnerClasses
+ */
+
+public class DiffResultAfterSameOperationInnerClasses {
+    public int i = 1;
+    private int j = 1;
+    public String s1 = "Hi, ";
+    private String s2 = "Hi, ";
+
+    public static void main(String[] args) {
+        InnerClass inner =
+                new DiffResultAfterSameOperationInnerClasses().new InnerClass();
+        if (!inner.test()) {
+            throw new AssertionError("Different results after same calculation");
+        }
+    }
+
+    class InnerClass {
+        public boolean test() {
+            i += i += 1;
+            j += j += 1;
+
+            s1 += s1 += "dude";
+            s2 += s2 += "dude";
+
+            System.out.println("s1 = " + s1);
+            System.out.println("s2 = " + s2);
+
+            return (i == j && i == 3 &&
+                    s1.equals(s2) && s1.endsWith("Hi, Hi, dude"));
+        }
+    }
+}