src/share/classes/com/sun/tools/javap/StackMapWriter.java

Tue, 25 Sep 2012 13:06:58 -0700

author
jjg
date
Tue, 25 Sep 2012 13:06:58 -0700
changeset 1339
0e5899f09dab
parent 581
f2fdd52e4e87
child 1648
a03c4a86ea2b
permissions
-rw-r--r--

7193657: provide internal ArrayUtils class to simplify common usage of arrays in javac
Reviewed-by: mcimadamore, jjg
Contributed-by: vicenterz@yahoo.es

     1 /*
     2  * Copyright (c) 2009, 2012, 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  */
    26 package com.sun.tools.javap;
    28 import java.util.Arrays;
    29 import java.util.HashMap;
    30 import java.util.Map;
    32 import com.sun.tools.classfile.AccessFlags;
    33 import com.sun.tools.classfile.Attribute;
    34 import com.sun.tools.classfile.Code_attribute;
    35 import com.sun.tools.classfile.ConstantPool;
    36 import com.sun.tools.classfile.ConstantPoolException;
    37 import com.sun.tools.classfile.Descriptor;
    38 import com.sun.tools.classfile.Descriptor.InvalidDescriptor;
    39 import com.sun.tools.classfile.Instruction;
    40 import com.sun.tools.classfile.Method;
    41 import com.sun.tools.classfile.StackMapTable_attribute;
    42 import com.sun.tools.classfile.StackMapTable_attribute.*;
    44 import static com.sun.tools.classfile.StackMapTable_attribute.verification_type_info.*;
    46 /**
    47  * Annotate instructions with stack map.
    48  *
    49  *  <p><b>This is NOT part of any supported API.
    50  *  If you write code that depends on this, you do so at your own risk.
    51  *  This code and its internal interfaces are subject to change or
    52  *  deletion without notice.</b>
    53  */
    54 public class StackMapWriter extends InstructionDetailWriter {
    55     static StackMapWriter instance(Context context) {
    56         StackMapWriter instance = context.get(StackMapWriter.class);
    57         if (instance == null)
    58             instance = new StackMapWriter(context);
    59         return instance;
    60     }
    62     protected StackMapWriter(Context context) {
    63         super(context);
    64         context.put(StackMapWriter.class, this);
    65         classWriter = ClassWriter.instance(context);
    66     }
    68     public void reset(Code_attribute attr) {
    69         setStackMap((StackMapTable_attribute) attr.attributes.get(Attribute.StackMapTable));
    70     }
    72     void setStackMap(StackMapTable_attribute attr) {
    73         if (attr == null) {
    74             map = null;
    75             return;
    76         }
    78         Method m = classWriter.getMethod();
    79         Descriptor d = m.descriptor;
    80         String[] args;
    81         try {
    82             ConstantPool cp = classWriter.getClassFile().constant_pool;
    83             String argString = d.getParameterTypes(cp);
    84             args = argString.substring(1, argString.length() - 1).split("[, ]+");
    85         } catch (ConstantPoolException e) {
    86             return;
    87         } catch (InvalidDescriptor e) {
    88             return;
    89         }
    90         boolean isStatic = m.access_flags.is(AccessFlags.ACC_STATIC);
    92         verification_type_info[] initialLocals = new verification_type_info[(isStatic ? 0 : 1) + args.length];
    93         if (!isStatic)
    94             initialLocals[0] = new CustomVerificationTypeInfo("this");
    95         for (int i = 0; i < args.length; i++) {
    96             initialLocals[(isStatic ? 0 : 1) + i] =
    97                     new CustomVerificationTypeInfo(args[i].replace(".", "/"));
    98         }
   100         map = new HashMap<Integer, StackMap>();
   101         StackMapBuilder builder = new StackMapBuilder();
   103         // using -1 as the pc for the initial frame effectively compensates for
   104         // the difference in behavior for the first stack map frame (where the
   105         // pc offset is just offset_delta) compared to subsequent frames (where
   106         // the pc offset is always offset_delta+1).
   107         int pc = -1;
   109         map.put(pc, new StackMap(initialLocals, empty));
   111         for (int i = 0; i < attr.entries.length; i++)
   112             pc = attr.entries[i].accept(builder, pc);
   113     }
   115     public void writeInitialDetails() {
   116         writeDetails(-1);
   117     }
   119     public void writeDetails(Instruction instr) {
   120         writeDetails(instr.getPC());
   121     }
   123     private void writeDetails(int pc) {
   124         if (map == null)
   125             return;
   127         StackMap m = map.get(pc);
   128         if (m != null) {
   129             print("StackMap locals: ", m.locals);
   130             print("StackMap stack: ", m.stack);
   131         }
   133     }
   135     void print(String label, verification_type_info[] entries) {
   136         print(label);
   137         for (int i = 0; i < entries.length; i++) {
   138             print(" ");
   139             print(entries[i]);
   140         }
   141         println();
   142     }
   144     void print(verification_type_info entry) {
   145         if (entry == null) {
   146             print("ERROR");
   147             return;
   148         }
   150         switch (entry.tag) {
   151             case -1:
   152                 print(((CustomVerificationTypeInfo) entry).text);
   153                 break;
   155             case ITEM_Top:
   156                 print("top");
   157                 break;
   159             case ITEM_Integer:
   160                 print("int");
   161                 break;
   163             case ITEM_Float:
   164                 print("float");
   165                 break;
   167             case ITEM_Long:
   168                 print("long");
   169                 break;
   171             case ITEM_Double:
   172                 print("double");
   173                 break;
   175             case ITEM_Null:
   176                 print("null");
   177                 break;
   179             case ITEM_UninitializedThis:
   180                 print("uninit_this");
   181                 break;
   183             case ITEM_Object:
   184                 try {
   185                     ConstantPool cp = classWriter.getClassFile().constant_pool;
   186                     ConstantPool.CONSTANT_Class_info class_info = cp.getClassInfo(((Object_variable_info) entry).cpool_index);
   187                     print(cp.getUTF8Value(class_info.name_index));
   188                 } catch (ConstantPoolException e) {
   189                     print("??");
   190                 }
   191                 break;
   193             case ITEM_Uninitialized:
   194                 print(((Uninitialized_variable_info) entry).offset);
   195                 break;
   196         }
   198     }
   200     private Map<Integer, StackMap> map;
   201     private ClassWriter classWriter;
   203     class StackMapBuilder
   204             implements StackMapTable_attribute.stack_map_frame.Visitor<Integer, Integer> {
   206         public Integer visit_same_frame(same_frame frame, Integer pc) {
   207             int new_pc = pc + frame.getOffsetDelta() + 1;
   208             StackMap m = map.get(pc);
   209             assert (m != null);
   210             map.put(new_pc, m);
   211             return new_pc;
   212         }
   214         public Integer visit_same_locals_1_stack_item_frame(same_locals_1_stack_item_frame frame, Integer pc) {
   215             int new_pc = pc + frame.getOffsetDelta() + 1;
   216             StackMap prev = map.get(pc);
   217             assert (prev != null);
   218             StackMap m = new StackMap(prev.locals, frame.stack);
   219             map.put(new_pc, m);
   220             return new_pc;
   221         }
   223         public Integer visit_same_locals_1_stack_item_frame_extended(same_locals_1_stack_item_frame_extended frame, Integer pc) {
   224             int new_pc = pc + frame.getOffsetDelta() + 1;
   225             StackMap prev = map.get(pc);
   226             assert (prev != null);
   227             StackMap m = new StackMap(prev.locals, frame.stack);
   228             map.put(new_pc, m);
   229             return new_pc;
   230         }
   232         public Integer visit_chop_frame(chop_frame frame, Integer pc) {
   233             int new_pc = pc + frame.getOffsetDelta() + 1;
   234             StackMap prev = map.get(pc);
   235             assert (prev != null);
   236             int k = 251 - frame.frame_type;
   237             verification_type_info[] new_locals = Arrays.copyOf(prev.locals, prev.locals.length - k);
   238             StackMap m = new StackMap(new_locals, empty);
   239             map.put(new_pc, m);
   240             return new_pc;
   241         }
   243         public Integer visit_same_frame_extended(same_frame_extended frame, Integer pc) {
   244             int new_pc = pc + frame.getOffsetDelta();
   245             StackMap m = map.get(pc);
   246             assert (m != null);
   247             map.put(new_pc, m);
   248             return new_pc;
   249         }
   251         public Integer visit_append_frame(append_frame frame, Integer pc) {
   252             int new_pc = pc + frame.getOffsetDelta() + 1;
   253             StackMap prev = map.get(pc);
   254             assert (prev != null);
   255             verification_type_info[] new_locals = new verification_type_info[prev.locals.length + frame.locals.length];
   256             System.arraycopy(prev.locals, 0, new_locals, 0, prev.locals.length);
   257             System.arraycopy(frame.locals, 0, new_locals, prev.locals.length, frame.locals.length);
   258             StackMap m = new StackMap(new_locals, empty);
   259             map.put(new_pc, m);
   260             return new_pc;
   261         }
   263         public Integer visit_full_frame(full_frame frame, Integer pc) {
   264             int new_pc = pc + frame.getOffsetDelta() + 1;
   265             StackMap m = new StackMap(frame.locals, frame.stack);
   266             map.put(new_pc, m);
   267             return new_pc;
   268         }
   270     }
   272     class StackMap {
   273         StackMap(verification_type_info[] locals, verification_type_info[] stack) {
   274             this.locals = locals;
   275             this.stack = stack;
   276         }
   278         private final verification_type_info[] locals;
   279         private final verification_type_info[] stack;
   280     }
   282     class CustomVerificationTypeInfo extends verification_type_info {
   283         public CustomVerificationTypeInfo(String text) {
   284             super(-1);
   285             this.text = text;
   286         }
   287         private String text;
   288     }
   290     private final verification_type_info[] empty = { };
   291 }

mercurial