1 /*

     2  * Copyright (c) 2013, 2018, 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.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 package jdk.jfr.internal.instrument;

    27 

    28 import java.util.ArrayList;

    29 import java.util.List;

    30 

    31 import jdk.internal.org.objectweb.asm.Label;

    32 import jdk.internal.org.objectweb.asm.MethodVisitor;

    33 import jdk.internal.org.objectweb.asm.Opcodes;

    34 import jdk.internal.org.objectweb.asm.commons.LocalVariablesSorter;

    35 import jdk.internal.org.objectweb.asm.commons.Remapper;

    36 import jdk.internal.org.objectweb.asm.commons.SimpleRemapper;

    37 import jdk.internal.org.objectweb.asm.tree.MethodNode;

    38 import jdk.jfr.internal.LogLevel;

    39 import jdk.jfr.internal.LogTag;

    40 import jdk.jfr.internal.Logger;

    41 

    42 /**

    43  * Class responsible for finding the call to inline and inlining it.

    44  *

    45  * This code is heavily influenced by section 3.2.6 "Inline Method" in

    46  * "Using ASM framework to implement common bytecode transformation patterns",

    47  * E. Kuleshov, AOSD.07, March 2007, Vancouver, Canada.

    48  * http://asm.ow2.org/index.html

    49  */

    50 @Deprecated

    51 final class JIMethodCallInliner extends LocalVariablesSorter {

    52 

    53     private final String oldClass;

    54     private final String newClass;

    55     private final MethodNode inlineTarget;

    56     private final List<CatchBlock> blocks = new ArrayList<>();

    57     private boolean inlining;

    58 

    59     /**

    60      * inlineTarget defines the method to inline and also contains the actual

    61      * code to inline.

    62      *

    63      * @param access

    64      * @param desc

    65      * @param mv

    66      * @param inlineTarget

    67      * @param oldClass

    68      * @param newClass

    69      * @param logger

    70      */

    71     public JIMethodCallInliner(int access, String desc, MethodVisitor mv,

    72             MethodNode inlineTarget, String oldClass, String newClass) {

    73         super(Opcodes.ASM5, access, desc, mv);

    74         this.oldClass = oldClass;

    75         this.newClass = newClass;

    76         this.inlineTarget = inlineTarget;

    77 

    78         Logger.log(LogTag.JFR_SYSTEM_BYTECODE, LogLevel.DEBUG, "MethodCallInliner: targetMethod=" + newClass + "."

    79                 + inlineTarget.name + inlineTarget.desc);

    80     }

    81 

    82     @Override

    83     public void visitMethodInsn(int opcode, String owner, String name,

    84             String desc, boolean itf) {

    85         // Now we are looking at method call in the source method

    86         if (!shouldBeInlined(owner, name, desc)) {

    87             // If this method call should not be inlined, just keep it

    88             mv.visitMethodInsn(opcode, owner, name, desc, itf);

    89             return;

    90         }

    91         // If the call should be inlined, we create a MethodInliningAdapter

    92         // The MIA will walk the instructions in the inlineTarget and add them

    93         // to the current method, doing the necessary name remappings.

    94         Logger.log(LogTag.JFR_SYSTEM_BYTECODE, LogLevel.DEBUG, "Inlining call to " + name + desc);

    95         Remapper remapper = new SimpleRemapper(oldClass, newClass);

    96         Label end = new Label();

    97         inlining = true;

    98         inlineTarget.instructions.resetLabels();

    99         JIMethodInliningAdapter mia = new JIMethodInliningAdapter(this, end,

   100                 opcode == Opcodes.INVOKESTATIC ? Opcodes.ACC_STATIC : 0, desc,

   101                 remapper);

   102         inlineTarget.accept(mia);

   103         inlining = false;

   104         super.visitLabel(end);

   105     }

   106 

   107     /**

   108      * Determine if the method should be inlined or not.

   109      */

   110     private boolean shouldBeInlined(String owner, String name, String desc) {

   111         return inlineTarget.desc.equals(desc) && inlineTarget.name.equals(name)

   112                 && owner.equals(newClass.replace('.', '/'));

   113     }

   114 

   115     @Override

   116     public void visitTryCatchBlock(Label start, Label end, Label handler,

   117             String type) {

   118         if (!inlining) {

   119             // try-catch blocks are saved here and replayed at the end

   120             // of the method (in visitMaxs)

   121             blocks.add(new CatchBlock(start, end, handler, type));

   122         } else {

   123             super.visitTryCatchBlock(start, end, handler, type);

   124         }

   125     }

   126 

   127     @Override

   128     public void visitMaxs(int stack, int locals) {

   129         for (CatchBlock b : blocks) {

   130             super.visitTryCatchBlock(b.start, b.end, b.handler, b.type);

   131         }

   132         super.visitMaxs(stack, locals);

   133     }

   134 

   135     static final class CatchBlock {

   136 

   137         final Label start;

   138         final Label end;

   139         final Label handler;

   140         final String type;

   141 

   142         CatchBlock(Label start, Label end, Label handler, String type) {

   143             this.start = start;

   144             this.end = end;

   145             this.handler = handler;

   146             this.type = type;

   147         }

   148     }

   149 }