src.jdk.jdeps.share.classes.com.sun.tools.javap.CodeWriter Maven / Gradle / Ivy
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/*
* Copyright (c) 2007, 2020, 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
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package com.sun.tools.javap;
import java.util.ArrayList;
import java.util.List;
import com.sun.tools.classfile.AccessFlags;
import com.sun.tools.classfile.Code_attribute;
import com.sun.tools.classfile.ConstantPool;
import com.sun.tools.classfile.ConstantPoolException;
import com.sun.tools.classfile.DescriptorException;
import com.sun.tools.classfile.Instruction;
import com.sun.tools.classfile.Instruction.TypeKind;
import com.sun.tools.classfile.Method;
/*
* Write the contents of a Code attribute.
*
* 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 CodeWriter extends BasicWriter {
public static CodeWriter instance(Context context) {
CodeWriter instance = context.get(CodeWriter.class);
if (instance == null)
instance = new CodeWriter(context);
return instance;
}
protected CodeWriter(Context context) {
super(context);
context.put(CodeWriter.class, this);
attrWriter = AttributeWriter.instance(context);
classWriter = ClassWriter.instance(context);
constantWriter = ConstantWriter.instance(context);
sourceWriter = SourceWriter.instance(context);
tryBlockWriter = TryBlockWriter.instance(context);
stackMapWriter = StackMapWriter.instance(context);
localVariableTableWriter = LocalVariableTableWriter.instance(context);
localVariableTypeTableWriter = LocalVariableTypeTableWriter.instance(context);
typeAnnotationWriter = TypeAnnotationWriter.instance(context);
options = Options.instance(context);
}
void write(Code_attribute attr, ConstantPool constant_pool) {
println("Code:");
indent(+1);
writeVerboseHeader(attr, constant_pool);
writeInstrs(attr);
writeExceptionTable(attr);
attrWriter.write(attr, attr.attributes, constant_pool);
indent(-1);
}
public void writeVerboseHeader(Code_attribute attr, ConstantPool constant_pool) {
Method method = classWriter.getMethod();
String argCount;
try {
int n = method.descriptor.getParameterCount(constant_pool);
if (!method.access_flags.is(AccessFlags.ACC_STATIC))
++n; // for 'this'
argCount = Integer.toString(n);
} catch (ConstantPoolException e) {
argCount = report(e);
} catch (DescriptorException e) {
argCount = report(e);
}
println("stack=" + attr.max_stack +
", locals=" + attr.max_locals +
", args_size=" + argCount);
}
public void writeInstrs(Code_attribute attr) {
List detailWriters = getDetailWriters(attr);
for (Instruction instr: attr.getInstructions()) {
try {
for (InstructionDetailWriter w: detailWriters)
w.writeDetails(instr);
writeInstr(instr);
} catch (ArrayIndexOutOfBoundsException | IllegalStateException e) {
println(report("error at or after byte " + instr.getPC()));
break;
}
}
for (InstructionDetailWriter w: detailWriters)
w.flush();
}
public void writeInstr(Instruction instr) {
print(String.format("%4d: %-13s ", instr.getPC(), instr.getMnemonic()));
// compute the number of indentations for the body of multi-line instructions
// This is 6 (the width of "%4d: "), divided by the width of each indentation level,
// and rounded up to the next integer.
int indentWidth = options.indentWidth;
int indent = (6 + indentWidth - 1) / indentWidth;
instr.accept(instructionPrinter, indent);
println();
}
// where
Instruction.KindVisitor instructionPrinter =
new Instruction.KindVisitor<>() {
public Void visitNoOperands(Instruction instr, Integer indent) {
return null;
}
public Void visitArrayType(Instruction instr, TypeKind kind, Integer indent) {
print(" " + kind.name);
return null;
}
public Void visitBranch(Instruction instr, int offset, Integer indent) {
print((instr.getPC() + offset));
return null;
}
public Void visitConstantPoolRef(Instruction instr, int index, Integer indent) {
print("#" + index);
tab();
print("// ");
printConstant(index);
return null;
}
public Void visitConstantPoolRefAndValue(Instruction instr, int index, int value, Integer indent) {
print("#" + index + ", " + value);
tab();
print("// ");
printConstant(index);
return null;
}
public Void visitLocal(Instruction instr, int index, Integer indent) {
print(index);
return null;
}
public Void visitLocalAndValue(Instruction instr, int index, int value, Integer indent) {
print(index + ", " + value);
return null;
}
public Void visitLookupSwitch(Instruction instr,
int default_, int npairs, int[] matches, int[] offsets, Integer indent) {
int pc = instr.getPC();
print("{ // " + npairs);
indent(indent);
for (int i = 0; i < npairs; i++) {
print(String.format("%n%12d: %d", matches[i], (pc + offsets[i])));
}
print("\n default: " + (pc + default_) + "\n}");
indent(-indent);
return null;
}
public Void visitTableSwitch(Instruction instr,
int default_, int low, int high, int[] offsets, Integer indent) {
int pc = instr.getPC();
print("{ // " + low + " to " + high);
indent(indent);
for (int i = 0; i < offsets.length; i++) {
print(String.format("%n%12d: %d", (low + i), (pc + offsets[i])));
}
print("\n default: " + (pc + default_) + "\n}");
indent(-indent);
return null;
}
public Void visitValue(Instruction instr, int value, Integer indent) {
print(value);
return null;
}
public Void visitUnknown(Instruction instr, Integer indent) {
return null;
}
};
public void writeExceptionTable(Code_attribute attr) {
if (attr.exception_table_length > 0) {
println("Exception table:");
indent(+1);
println(" from to target type");
for (int i = 0; i < attr.exception_table.length; i++) {
Code_attribute.Exception_data handler = attr.exception_table[i];
print(String.format(" %5d %5d %5d",
handler.start_pc, handler.end_pc, handler.handler_pc));
print(" ");
int catch_type = handler.catch_type;
if (catch_type == 0) {
println("any");
} else {
print("Class ");
println(constantWriter.stringValue(catch_type));
}
}
indent(-1);
}
}
private void printConstant(int index) {
constantWriter.write(index);
}
private List getDetailWriters(Code_attribute attr) {
List detailWriters = new ArrayList<>();
if (options.details.contains(InstructionDetailWriter.Kind.SOURCE)) {
sourceWriter.reset(classWriter.getClassFile(), attr);
if (sourceWriter.hasSource())
detailWriters.add(sourceWriter);
else
println("(Source code not available)");
}
if (options.details.contains(InstructionDetailWriter.Kind.LOCAL_VARS)) {
localVariableTableWriter.reset(attr);
detailWriters.add(localVariableTableWriter);
}
if (options.details.contains(InstructionDetailWriter.Kind.LOCAL_VAR_TYPES)) {
localVariableTypeTableWriter.reset(attr);
detailWriters.add(localVariableTypeTableWriter);
}
if (options.details.contains(InstructionDetailWriter.Kind.STACKMAPS)) {
stackMapWriter.reset(attr);
stackMapWriter.writeInitialDetails();
detailWriters.add(stackMapWriter);
}
if (options.details.contains(InstructionDetailWriter.Kind.TRY_BLOCKS)) {
tryBlockWriter.reset(attr);
detailWriters.add(tryBlockWriter);
}
if (options.details.contains(InstructionDetailWriter.Kind.TYPE_ANNOS)) {
typeAnnotationWriter.reset(attr);
detailWriters.add(typeAnnotationWriter);
}
return detailWriters;
}
private AttributeWriter attrWriter;
private ClassWriter classWriter;
private ConstantWriter constantWriter;
private LocalVariableTableWriter localVariableTableWriter;
private LocalVariableTypeTableWriter localVariableTypeTableWriter;
private TypeAnnotationWriter typeAnnotationWriter;
private SourceWriter sourceWriter;
private StackMapWriter stackMapWriter;
private TryBlockWriter tryBlockWriter;
private Options options;
}