src.jdk.jdeps.share.classes.com.sun.tools.javap.StackMapWriter Maven / Gradle / Ivy
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/*
* Copyright (c) 2009, 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. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* 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
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*/
package com.sun.tools.javap;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import com.sun.tools.classfile.AccessFlags;
import com.sun.tools.classfile.Attribute;
import com.sun.tools.classfile.Code_attribute;
import com.sun.tools.classfile.ConstantPool;
import com.sun.tools.classfile.ConstantPoolException;
import com.sun.tools.classfile.Descriptor;
import com.sun.tools.classfile.Descriptor.InvalidDescriptor;
import com.sun.tools.classfile.Instruction;
import com.sun.tools.classfile.Method;
import com.sun.tools.classfile.StackMapTable_attribute;
import com.sun.tools.classfile.StackMapTable_attribute.*;
import static com.sun.tools.classfile.StackMapTable_attribute.verification_type_info.*;
/**
* Annotate instructions with stack map.
*
* This is NOT part of any supported API.
* If you write code that depends on this, you do so at your own risk.
* This code and its internal interfaces are subject to change or
* deletion without notice.
*/
public class StackMapWriter extends InstructionDetailWriter {
static StackMapWriter instance(Context context) {
StackMapWriter instance = context.get(StackMapWriter.class);
if (instance == null)
instance = new StackMapWriter(context);
return instance;
}
protected StackMapWriter(Context context) {
super(context);
context.put(StackMapWriter.class, this);
classWriter = ClassWriter.instance(context);
}
public void reset(Code_attribute attr) {
setStackMap((StackMapTable_attribute) attr.attributes.get(Attribute.StackMapTable));
}
void setStackMap(StackMapTable_attribute attr) {
if (attr == null) {
map = null;
return;
}
Method m = classWriter.getMethod();
Descriptor d = m.descriptor;
String[] args;
try {
ConstantPool cp = classWriter.getClassFile().constant_pool;
String argString = d.getParameterTypes(cp);
args = argString.substring(1, argString.length() - 1).split("[, ]+");
} catch (ConstantPoolException | InvalidDescriptor e) {
return;
}
boolean isStatic = m.access_flags.is(AccessFlags.ACC_STATIC);
verification_type_info[] initialLocals = new verification_type_info[(isStatic ? 0 : 1) + args.length];
if (!isStatic)
initialLocals[0] = new CustomVerificationTypeInfo("this");
for (int i = 0; i < args.length; i++) {
initialLocals[(isStatic ? 0 : 1) + i] =
new CustomVerificationTypeInfo(args[i].replace(".", "/"));
}
map = new HashMap<>();
StackMapBuilder builder = new StackMapBuilder();
// using -1 as the pc for the initial frame effectively compensates for
// the difference in behavior for the first stack map frame (where the
// pc offset is just offset_delta) compared to subsequent frames (where
// the pc offset is always offset_delta+1).
int pc = -1;
map.put(pc, new StackMap(initialLocals, empty));
for (int i = 0; i < attr.entries.length; i++)
pc = attr.entries[i].accept(builder, pc);
}
public void writeInitialDetails() {
writeDetails(-1);
}
public void writeDetails(Instruction instr) {
writeDetails(instr.getPC());
}
private void writeDetails(int pc) {
if (map == null)
return;
StackMap m = map.get(pc);
if (m != null) {
print("StackMap locals: ", m.locals);
print("StackMap stack: ", m.stack);
}
}
void print(String label, verification_type_info[] entries) {
print(label);
for (int i = 0; i < entries.length; i++) {
print(" ");
print(entries[i]);
}
println();
}
void print(verification_type_info entry) {
if (entry == null) {
print("ERROR");
return;
}
switch (entry.tag) {
case -1:
print(((CustomVerificationTypeInfo) entry).text);
break;
case ITEM_Top:
print("top");
break;
case ITEM_Integer:
print("int");
break;
case ITEM_Float:
print("float");
break;
case ITEM_Long:
print("long");
break;
case ITEM_Double:
print("double");
break;
case ITEM_Null:
print("null");
break;
case ITEM_UninitializedThis:
print("uninit_this");
break;
case ITEM_Object:
try {
ConstantPool cp = classWriter.getClassFile().constant_pool;
ConstantPool.CONSTANT_Class_info class_info = cp.getClassInfo(((Object_variable_info) entry).cpool_index);
print(cp.getUTF8Value(class_info.name_index));
} catch (ConstantPoolException e) {
print("??");
}
break;
case ITEM_Uninitialized:
print(((Uninitialized_variable_info) entry).offset);
break;
}
}
private Map map;
private ClassWriter classWriter;
class StackMapBuilder
implements StackMapTable_attribute.stack_map_frame.Visitor {
public Integer visit_same_frame(same_frame frame, Integer pc) {
int new_pc = pc + frame.getOffsetDelta() + 1;
StackMap m = map.get(pc);
assert (m != null);
map.put(new_pc, m);
return new_pc;
}
public Integer visit_same_locals_1_stack_item_frame(same_locals_1_stack_item_frame frame, Integer pc) {
int new_pc = pc + frame.getOffsetDelta() + 1;
StackMap prev = map.get(pc);
assert (prev != null);
StackMap m = new StackMap(prev.locals, frame.stack);
map.put(new_pc, m);
return new_pc;
}
public Integer visit_same_locals_1_stack_item_frame_extended(same_locals_1_stack_item_frame_extended frame, Integer pc) {
int new_pc = pc + frame.getOffsetDelta() + 1;
StackMap prev = map.get(pc);
assert (prev != null);
StackMap m = new StackMap(prev.locals, frame.stack);
map.put(new_pc, m);
return new_pc;
}
public Integer visit_chop_frame(chop_frame frame, Integer pc) {
int new_pc = pc + frame.getOffsetDelta() + 1;
StackMap prev = map.get(pc);
assert (prev != null);
int k = 251 - frame.frame_type;
verification_type_info[] new_locals = Arrays.copyOf(prev.locals, prev.locals.length - k);
StackMap m = new StackMap(new_locals, empty);
map.put(new_pc, m);
return new_pc;
}
public Integer visit_same_frame_extended(same_frame_extended frame, Integer pc) {
int new_pc = pc + frame.getOffsetDelta();
StackMap m = map.get(pc);
assert (m != null);
map.put(new_pc, m);
return new_pc;
}
public Integer visit_append_frame(append_frame frame, Integer pc) {
int new_pc = pc + frame.getOffsetDelta() + 1;
StackMap prev = map.get(pc);
assert (prev != null);
verification_type_info[] new_locals = new verification_type_info[prev.locals.length + frame.locals.length];
System.arraycopy(prev.locals, 0, new_locals, 0, prev.locals.length);
System.arraycopy(frame.locals, 0, new_locals, prev.locals.length, frame.locals.length);
StackMap m = new StackMap(new_locals, empty);
map.put(new_pc, m);
return new_pc;
}
public Integer visit_full_frame(full_frame frame, Integer pc) {
int new_pc = pc + frame.getOffsetDelta() + 1;
StackMap m = new StackMap(frame.locals, frame.stack);
map.put(new_pc, m);
return new_pc;
}
}
static class StackMap {
StackMap(verification_type_info[] locals, verification_type_info[] stack) {
this.locals = locals;
this.stack = stack;
}
private final verification_type_info[] locals;
private final verification_type_info[] stack;
}
static class CustomVerificationTypeInfo extends verification_type_info {
public CustomVerificationTypeInfo(String text) {
super(-1);
this.text = text;
}
private String text;
}
private final verification_type_info[] empty = { };
}