1 /*
   2  * Copyright (c) 2014, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 import java.lang.reflect.Constructor;
  25 import java.lang.reflect.Method;
  26 
  27 import jdk.internal.org.objectweb.asm.ClassWriter;
  28 import jdk.internal.org.objectweb.asm.Label;
  29 import jdk.internal.org.objectweb.asm.MethodVisitor;
  30 import static jdk.internal.org.objectweb.asm.Opcodes.*;
  31 
  32 /**
  33  * @test
  34  * @bug 8051344
  35  * @summary Force OSR compilation with non-empty stack at the OSR entry point.
  36  * @modules java.base/jdk.internal.org.objectweb.asm
  37  * @compile -XDignore.symbol.file TestOSRWithNonEmptyStack.java
  38  * @run main/othervm -XX:CompileOnly=TestCase.test TestOSRWithNonEmptyStack
  39  */
  40 public class TestOSRWithNonEmptyStack extends ClassLoader {
  41     private static final int CLASS_FILE_VERSION = 52;
  42     private static final String CLASS_NAME = "TestCase";
  43     private static final String METHOD_NAME = "test";
  44     private static final int ITERATIONS = 1_000_000;
  45 
  46     private static byte[] generateTestClass() {
  47         ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES);
  48 
  49         cw.visit(TestOSRWithNonEmptyStack.CLASS_FILE_VERSION, ACC_PUBLIC,
  50                 TestOSRWithNonEmptyStack.CLASS_NAME, null, "java/lang/Object",
  51                 null);
  52 
  53         TestOSRWithNonEmptyStack.generateConstructor(cw);
  54         TestOSRWithNonEmptyStack.generateTestMethod(cw);
  55 
  56         cw.visitEnd();
  57         return cw.toByteArray();
  58     }
  59 
  60     private static void generateConstructor(ClassWriter classWriter) {
  61         MethodVisitor mv = classWriter.visitMethod(ACC_PUBLIC, "<init>", "()V",
  62                 null, null);
  63 
  64         mv.visitCode();
  65 
  66         mv.visitVarInsn(ALOAD, 0);
  67         mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V",
  68                 false);
  69         mv.visitInsn(RETURN);
  70 
  71         mv.visitMaxs(0, 0);
  72         mv.visitEnd();
  73     }
  74 
  75     private static void generateTestMethod(ClassWriter classWriter) {
  76         MethodVisitor mv = classWriter.visitMethod(ACC_PUBLIC,
  77                 TestOSRWithNonEmptyStack.METHOD_NAME, "()V", null, null);
  78         Label osrEntryPoint = new Label();
  79 
  80         mv.visitCode();
  81         // Push 'this' into stack before OSR entry point to bail out compilation
  82         mv.visitVarInsn(ALOAD, 0);
  83         // Setup loop counter
  84         mv.visitInsn(ICONST_0);
  85         mv.visitVarInsn(ISTORE, 1);
  86         // Begin loop
  87         mv.visitLabel(osrEntryPoint);
  88         // Increment loop counter
  89         mv.visitVarInsn(ILOAD, 1);
  90         mv.visitInsn(ICONST_1);
  91         mv.visitInsn(IADD);
  92         // Duplicate it for loop condition check
  93         mv.visitInsn(DUP);
  94         mv.visitVarInsn(ISTORE, 1);
  95         // Check loop condition
  96         mv.visitLdcInsn(TestOSRWithNonEmptyStack.ITERATIONS);
  97         mv.visitJumpInsn(IF_ICMPLT, osrEntryPoint);
  98         // Pop 'this'.
  99         mv.visitInsn(POP);
 100         mv.visitInsn(RETURN);
 101 
 102         mv.visitMaxs(0, 0);
 103         mv.visitEnd();
 104     }
 105 
 106     private void run() {
 107         byte[] bytecode = TestOSRWithNonEmptyStack.generateTestClass();
 108 
 109         try {
 110             Class klass = defineClass(TestOSRWithNonEmptyStack.CLASS_NAME,
 111                     bytecode, 0, bytecode.length);
 112 
 113             Constructor ctor = klass.getConstructor();
 114             Method method = klass.getDeclaredMethod(
 115                     TestOSRWithNonEmptyStack.METHOD_NAME);
 116 
 117             Object testCase = ctor.newInstance();
 118             method.invoke(testCase);
 119         } catch (Exception e) {
 120             throw new RuntimeException(
 121                     "Test bug: generated class should be valid.", e);
 122         }
 123     }
 124 
 125     public static void main(String args[]) {
 126         new TestOSRWithNonEmptyStack().run();
 127     }
 128 }