[PATCH] Fix POP2 opcode handling bug with two category 1 values at the stack top.

src/org/jetbrains/java/decompiler/modules/decompiler/ExprProcessor.java

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2017 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package org.jetbrains.java.decompiler.modules.decompiler;
 
 import org.jetbrains.java.decompiler.code.CodeConstants;
@@ -618,8 +604,17 @@ public class ExprProcessor implements CodeConstants {
           stack.pop();
           break;
         case opc_pop:
+          stack.pop();
+          break;
         case opc_pop2:
+          if (stack.getByOffset(-1).getExprType().stackSize == 1) {
+            // Since value at the top of the stack is a value of category 1 (JVMS9 2.11.1)
+            // we should remove one more item from the stack.
+            // See JVMS9 pop2 chapter.
+            stack.pop();
+          }
           stack.pop();
+          break;
       }
     }
   }

test/org/jetbrains/java/decompiler/SingleClassesTest.java

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2017 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package org.jetbrains.java.decompiler;
 
 import org.jetbrains.java.decompiler.main.decompiler.ConsoleDecompiler;
@@ -111,6 +97,10 @@ public class SingleClassesTest {
   @Test public void testLambdaParams() { doTest("pkg/TestLambdaParams"); }
   @Test public void testInterfaceMethods() { doTest("pkg/TestInterfaceMethods"); }
   @Test public void testConstType() { doTest("pkg/TestConstType"); }
+  @Test public void testPop2OneDoublePop2() { doTest("pkg/TestPop2OneDoublePop2"); }
+  @Test public void testPop2OneLongPop2() { doTest("pkg/TestPop2OneLongPop2"); }
+  @Test public void testPop2TwoIntPop2() { doTest("pkg/TestPop2TwoIntPop2"); }
+  @Test public void testPop2TwoIntTwoPop() { doTest("pkg/TestPop2TwoIntTwoPop"); }
 
   // TODO: fix all below
   //@Test public void testPackageInfo() { doTest("pkg/package-info"); }

testData/results/TestPop2OneDoublePop2.dec

@@ -0,0 +1,27 @@
+package pkg;
+
+public class TestPop2OneDoublePop2 {
+   public static void main(String... var0) {
+      double var10002 = 3.14159265358D;// 24
+      System.out.println(1234567890);// 22 23 26
+   }// 27
+}
+
+class 'pkg/TestPop2OneDoublePop2' {
+   method 'main ([Ljava/lang/String;)V' {
+      0      5
+      3      5
+      5      4
+      9      5
+      c      6
+   }
+}
+
+Lines mapping:
+22 <-> 6
+23 <-> 6
+24 <-> 5
+26 <-> 6
+27 <-> 7
+Not mapped:
+25

testData/results/TestPop2OneLongPop2.dec

@@ -0,0 +1,27 @@
+package pkg;
+
+public class TestPop2OneLongPop2 {
+   public static void main(String... var0) {
+      long var10002 = -889275714L;// 24
+      System.out.println(1234567890);// 22 23 26
+   }// 27
+}
+
+class 'pkg/TestPop2OneLongPop2' {
+   method 'main ([Ljava/lang/String;)V' {
+      0      5
+      3      5
+      5      4
+      9      5
+      c      6
+   }
+}
+
+Lines mapping:
+22 <-> 6
+23 <-> 6
+24 <-> 5
+26 <-> 6
+27 <-> 7
+Not mapped:
+25

testData/results/TestPop2TwoIntPop2.dec

@@ -0,0 +1,30 @@
+package pkg;
+
+public class TestPop2TwoIntPop2 {
+   public static void main(String... var0) {
+      char var10002 = '쫾';// 24
+      char var10003 = '몾';// 25
+      System.out.println(1234567890);// 22 23 27
+   }// 28
+}
+
+class 'pkg/TestPop2TwoIntPop2' {
+   method 'main ([Ljava/lang/String;)V' {
+      0      6
+      3      6
+      5      4
+      7      5
+      a      6
+      d      7
+   }
+}
+
+Lines mapping:
+22 <-> 7
+23 <-> 7
+24 <-> 5
+25 <-> 6
+27 <-> 7
+28 <-> 8
+Not mapped:
+26

testData/results/TestPop2TwoIntTwoPop.dec

@@ -0,0 +1,31 @@
+package pkg;
+
+public class TestPop2TwoIntTwoPop {
+   public static void main(String... var0) {
+      char var10002 = '쫾';// 24
+      char var10003 = '몾';// 25
+      System.out.println(1234567890);// 22 23 28
+   }// 29
+}
+
+class 'pkg/TestPop2TwoIntTwoPop' {
+   method 'main ([Ljava/lang/String;)V' {
+      0      6
+      3      6
+      5      4
+      7      5
+      b      6
+      e      7
+   }
+}
+
+Lines mapping:
+22 <-> 7
+23 <-> 7
+24 <-> 5
+25 <-> 6
+28 <-> 7
+29 <-> 8
+Not mapped:
+26
+27

testData/src/pkg/TestPop2OneDoublePop2.jasm

@@ -0,0 +1,30 @@
+/**
+ * This code can be assembled with <a href="https://wiki.openjdk.java.net/display/CodeTools/asmtools">asmtools</a>
+ * using <code>asmtools jasm -g *.jasm</code> command line.
+ */
+package  pkg;
+
+super public class TestPop2OneDoublePop2
+	version 52:0
+{
+
+public Method "<init>":"()V"
+	stack 1 locals 1
+{
+		aload_0;
+		invokespecial	Method java/lang/Object."<init>":"()V";
+		return;
+}
+
+public static varargs Method main:"([Ljava/lang/String;)V"
+	stack 4 locals 1
+{
+		getstatic	Field java/lang/System.out:"Ljava/io/PrintStream;";
+		ldc int 1234567890;
+		ldc2_w double 3.14159265358D;
+		pop2;
+		invokevirtual	Method java/io/PrintStream.println:"(I)V";
+		return;
+}
+
+} // end Class TestPop2OneDoublePop2

testData/src/pkg/TestPop2OneLongPop2.jasm

@@ -0,0 +1,30 @@
+/**
+ * This code can be assembled with <a href="https://wiki.openjdk.java.net/display/CodeTools/asmtools">asmtools</a>
+ * using <code>asmtools jasm -g *.jasm</code> command line.
+ */
+package  pkg;
+
+super public class TestPop2OneLongPop2
+	version 52:0
+{
+
+public Method "<init>":"()V"
+	stack 1 locals 1
+{
+		aload_0;
+		invokespecial	Method java/lang/Object."<init>":"()V";
+		return;
+}
+
+public static varargs Method main:"([Ljava/lang/String;)V"
+	stack 4 locals 1
+{
+		getstatic	Field java/lang/System.out:"Ljava/io/PrintStream;";
+		ldc int 1234567890;
+		ldc2_w long 0xCAFEBABE;
+		pop2;
+		invokevirtual	Method java/io/PrintStream.println:"(I)V";
+		return;
+}
+
+} // end Class TestPop2OneLongPop2

testData/src/pkg/TestPop2TwoIntPop2.jasm

@@ -0,0 +1,31 @@
+/**
+ * This code can be assembled with <a href="https://wiki.openjdk.java.net/display/CodeTools/asmtools">asmtools</a>
+ * using <code>asmtools jasm -g *.jasm</code> command line.
+ */
+package  pkg;
+
+super public class TestPop2TwoIntPop2
+	version 52:0
+{
+
+public Method "<init>":"()V"
+	stack 1 locals 1
+{
+		aload_0;
+		invokespecial	Method java/lang/Object."<init>":"()V";
+		return;
+}
+
+public static varargs Method main:"([Ljava/lang/String;)V"
+	stack 4 locals 1
+{
+		getstatic	Field java/lang/System.out:"Ljava/io/PrintStream;";
+		ldc int 1234567890;
+		ldc int 0xCAFE;
+		ldc int 0xBABE;
+		pop2;
+		invokevirtual	Method java/io/PrintStream.println:"(I)V";
+		return;
+}
+
+} // end Class TestPop2TwoIntPop2

testData/src/pkg/TestPop2TwoIntTwoPop.jasm

@@ -0,0 +1,32 @@
+/**
+ * This code can be assembled with <a href="https://wiki.openjdk.java.net/display/CodeTools/asmtools">asmtools</a>
+ * using <code>asmtools jasm -g *.jasm</code> command line.
+ */
+package  pkg;
+
+super public class TestPop2TwoIntTwoPop
+	version 52:0
+{
+
+public Method "<init>":"()V"
+	stack 1 locals 1
+{
+		aload_0;
+		invokespecial	Method java/lang/Object."<init>":"()V";
+		return;
+}
+
+public static varargs Method main:"([Ljava/lang/String;)V"
+	stack 4 locals 1
+{
+		getstatic	Field java/lang/System.out:"Ljava/io/PrintStream;";
+		ldc int 1234567890;
+		ldc int 0xCAFE;
+		ldc int 0xBABE;
+		pop;
+		pop;
+		invokevirtual	Method java/io/PrintStream.println:"(I)V";
+		return;
+}
+
+} // end Class TestPop2TwoIntTwoPop