Back to index...

	/*
	* 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.
	*/

	/*
	* This file is available under and governed by the GNU General Public
	* License version 2 only, as published by the Free Software Foundation.
	* However, the following notice accompanied the original version of this
	* file:
	*
	* ASM: a very small and fast Java bytecode manipulation framework
	* Copyright (c) 2000-2011 INRIA, France Telecom
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* 3. Neither the name of the copyright holders nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	* THE POSSIBILITY OF SUCH DAMAGE.
	*/
	package jdk.internal.org.objectweb.asm.tree.analysis;

	import java.util.List;
	import jdk.internal.org.objectweb.asm.Type;
	import jdk.internal.org.objectweb.asm.tree.AbstractInsnNode;
	import jdk.internal.org.objectweb.asm.tree.FieldInsnNode;
	import jdk.internal.org.objectweb.asm.tree.InvokeDynamicInsnNode;
	import jdk.internal.org.objectweb.asm.tree.MethodInsnNode;

	/**
	* An extended {@link BasicInterpreter} that checks that bytecode instructions are correctly used.
	*
	* @author Eric Bruneton
	* @author Bing Ran
	*/
	public class BasicVerifier extends BasicInterpreter {

	/**
	* Constructs a new {@link BasicVerifier} for the latest ASM API version. <i>Subclasses must not
	* use this constructor</i>. Instead, they must use the {@link #BasicVerifier(int)} version.
	*/
	public BasicVerifier() {
	super(/* latest api = */ ASM8);
	if (getClass() != BasicVerifier.class) {
	throw new IllegalStateException();
	}
	}

	/**
	* Constructs a new {@link BasicVerifier}.
	*
	* @param api the ASM API version supported by this interpreter. Must be one of {@link
	* jdk.internal.org.objectweb.asm.Opcodes#ASM4}, {@link jdk.internal.org.objectweb.asm.Opcodes#ASM5}, {@link
	* jdk.internal.org.objectweb.asm.Opcodes#ASM6}, {@link jdk.internal.org.objectweb.asm.Opcodes#ASM7} or {@link
	* jdk.internal.org.objectweb.asm.Opcodes#ASM8}.
	*/
	protected BasicVerifier(final int api) {
	super(api);
	}

	@Override
	public BasicValue copyOperation(final AbstractInsnNode insn, final BasicValue value)
	throws AnalyzerException {
	Value expected;
	switch (insn.getOpcode()) {
	case ILOAD:
	case ISTORE:
	expected = BasicValue.INT_VALUE;
	break;
	case FLOAD:
	case FSTORE:
	expected = BasicValue.FLOAT_VALUE;
	break;
	case LLOAD:
	case LSTORE:
	expected = BasicValue.LONG_VALUE;
	break;
	case DLOAD:
	case DSTORE:
	expected = BasicValue.DOUBLE_VALUE;
	break;
	case ALOAD:
	if (!value.isReference()) {
	throw new AnalyzerException(insn, null, "an object reference", value);
	}
	return value;
	case ASTORE:
	if (!value.isReference() && !BasicValue.RETURNADDRESS_VALUE.equals(value)) {
	throw new AnalyzerException(insn, null, "an object reference or a return address", value);
	}
	return value;
	default:
	return value;
	}
	if (!expected.equals(value)) {
	throw new AnalyzerException(insn, null, expected, value);
	}
	return value;
	}

	@Override
	public BasicValue unaryOperation(final AbstractInsnNode insn, final BasicValue value)
	throws AnalyzerException {
	BasicValue expected;
	switch (insn.getOpcode()) {
	case INEG:
	case IINC:
	case I2F:
	case I2L:
	case I2D:
	case I2B:
	case I2C:
	case I2S:
	case IFEQ:
	case IFNE:
	case IFLT:
	case IFGE:
	case IFGT:
	case IFLE:
	case TABLESWITCH:
	case LOOKUPSWITCH:
	case IRETURN:
	case NEWARRAY:
	case ANEWARRAY:
	expected = BasicValue.INT_VALUE;
	break;
	case FNEG:
	case F2I:
	case F2L:
	case F2D:
	case FRETURN:
	expected = BasicValue.FLOAT_VALUE;
	break;
	case LNEG:
	case L2I:
	case L2F:
	case L2D:
	case LRETURN:
	expected = BasicValue.LONG_VALUE;
	break;
	case DNEG:
	case D2I:
	case D2F:
	case D2L:
	case DRETURN:
	expected = BasicValue.DOUBLE_VALUE;
	break;
	case GETFIELD:
	expected = newValue(Type.getObjectType(((FieldInsnNode) insn).owner));
	break;
	case ARRAYLENGTH:
	if (!isArrayValue(value)) {
	throw new AnalyzerException(insn, null, "an array reference", value);
	}
	return super.unaryOperation(insn, value);
	case CHECKCAST:
	case ARETURN:
	case ATHROW:
	case INSTANCEOF:
	case MONITORENTER:
	case MONITOREXIT:
	case IFNULL:
	case IFNONNULL:
	if (!value.isReference()) {
	throw new AnalyzerException(insn, null, "an object reference", value);
	}
	return super.unaryOperation(insn, value);
	case PUTSTATIC:
	expected = newValue(Type.getType(((FieldInsnNode) insn).desc));
	break;
	default:
	throw new AssertionError();
	}
	if (!isSubTypeOf(value, expected)) {
	throw new AnalyzerException(insn, null, expected, value);
	}
	return super.unaryOperation(insn, value);
	}

	@Override
	public BasicValue binaryOperation(
	final AbstractInsnNode insn, final BasicValue value1, final BasicValue value2)
	throws AnalyzerException {
	BasicValue expected1;
	BasicValue expected2;
	switch (insn.getOpcode()) {
	case IALOAD:
	expected1 = newValue(Type.getType("[I"));
	expected2 = BasicValue.INT_VALUE;
	break;
	case BALOAD:
	if (isSubTypeOf(value1, newValue(Type.getType("[Z")))) {
	expected1 = newValue(Type.getType("[Z"));
	} else {
	expected1 = newValue(Type.getType("[B"));
	}
	expected2 = BasicValue.INT_VALUE;
	break;
	case CALOAD:
	expected1 = newValue(Type.getType("[C"));
	expected2 = BasicValue.INT_VALUE;
	break;
	case SALOAD:
	expected1 = newValue(Type.getType("[S"));
	expected2 = BasicValue.INT_VALUE;
	break;
	case LALOAD:
	expected1 = newValue(Type.getType("[J"));
	expected2 = BasicValue.INT_VALUE;
	break;
	case FALOAD:
	expected1 = newValue(Type.getType("[F"));
	expected2 = BasicValue.INT_VALUE;
	break;
	case DALOAD:
	expected1 = newValue(Type.getType("[D"));
	expected2 = BasicValue.INT_VALUE;
	break;
	case AALOAD:
	expected1 = newValue(Type.getType("[Ljava/lang/Object;"));
	expected2 = BasicValue.INT_VALUE;
	break;
	case IADD:
	case ISUB:
	case IMUL:
	case IDIV:
	case IREM:
	case ISHL:
	case ISHR:
	case IUSHR:
	case IAND:
	case IOR:
	case IXOR:
	case IF_ICMPEQ:
	case IF_ICMPNE:
	case IF_ICMPLT:
	case IF_ICMPGE:
	case IF_ICMPGT:
	case IF_ICMPLE:
	expected1 = BasicValue.INT_VALUE;
	expected2 = BasicValue.INT_VALUE;
	break;
	case FADD:
	case FSUB:
	case FMUL:
	case FDIV:
	case FREM:
	case FCMPL:
	case FCMPG:
	expected1 = BasicValue.FLOAT_VALUE;
	expected2 = BasicValue.FLOAT_VALUE;
	break;
	case LADD:
	case LSUB:
	case LMUL:
	case LDIV:
	case LREM:
	case LAND:
	case LOR:
	case LXOR:
	case LCMP:
	expected1 = BasicValue.LONG_VALUE;
	expected2 = BasicValue.LONG_VALUE;
	break;
	case LSHL:
	case LSHR:
	case LUSHR:
	expected1 = BasicValue.LONG_VALUE;
	expected2 = BasicValue.INT_VALUE;
	break;
	case DADD:
	case DSUB:
	case DMUL:
	case DDIV:
	case DREM:
	case DCMPL:
	case DCMPG:
	expected1 = BasicValue.DOUBLE_VALUE;
	expected2 = BasicValue.DOUBLE_VALUE;
	break;
	case IF_ACMPEQ:
	case IF_ACMPNE:
	expected1 = BasicValue.REFERENCE_VALUE;
	expected2 = BasicValue.REFERENCE_VALUE;
	break;
	case PUTFIELD:
	FieldInsnNode fieldInsn = (FieldInsnNode) insn;
	expected1 = newValue(Type.getObjectType(fieldInsn.owner));
	expected2 = newValue(Type.getType(fieldInsn.desc));
	break;
	default:
	throw new AssertionError();
	}
	if (!isSubTypeOf(value1, expected1)) {
	throw new AnalyzerException(insn, "First argument", expected1, value1);
	} else if (!isSubTypeOf(value2, expected2)) {
	throw new AnalyzerException(insn, "Second argument", expected2, value2);
	}
	if (insn.getOpcode() == AALOAD) {
	return getElementValue(value1);
	} else {
	return super.binaryOperation(insn, value1, value2);
	}
	}

	@Override
	public BasicValue ternaryOperation(
	final AbstractInsnNode insn,
	final BasicValue value1,
	final BasicValue value2,
	final BasicValue value3)
	throws AnalyzerException {
	BasicValue expected1;
	BasicValue expected3;
	switch (insn.getOpcode()) {
	case IASTORE:
	expected1 = newValue(Type.getType("[I"));
	expected3 = BasicValue.INT_VALUE;
	break;
	case BASTORE:
	if (isSubTypeOf(value1, newValue(Type.getType("[Z")))) {
	expected1 = newValue(Type.getType("[Z"));
	} else {
	expected1 = newValue(Type.getType("[B"));
	}
	expected3 = BasicValue.INT_VALUE;
	break;
	case CASTORE:
	expected1 = newValue(Type.getType("[C"));
	expected3 = BasicValue.INT_VALUE;
	break;
	case SASTORE:
	expected1 = newValue(Type.getType("[S"));
	expected3 = BasicValue.INT_VALUE;
	break;
	case LASTORE:
	expected1 = newValue(Type.getType("[J"));
	expected3 = BasicValue.LONG_VALUE;
	break;
	case FASTORE:
	expected1 = newValue(Type.getType("[F"));
	expected3 = BasicValue.FLOAT_VALUE;
	break;
	case DASTORE:
	expected1 = newValue(Type.getType("[D"));
	expected3 = BasicValue.DOUBLE_VALUE;
	break;
	case AASTORE:
	expected1 = value1;
	expected3 = BasicValue.REFERENCE_VALUE;
	break;
	default:
	throw new AssertionError();
	}
	if (!isSubTypeOf(value1, expected1)) {
	throw new AnalyzerException(
	insn, "First argument", "a " + expected1 + " array reference", value1);
	} else if (!BasicValue.INT_VALUE.equals(value2)) {
	throw new AnalyzerException(insn, "Second argument", BasicValue.INT_VALUE, value2);
	} else if (!isSubTypeOf(value3, expected3)) {
	throw new AnalyzerException(insn, "Third argument", expected3, value3);
	}
	return null;
	}

	@Override
	public BasicValue naryOperation(
	final AbstractInsnNode insn, final List<? extends BasicValue> values)
	throws AnalyzerException {
	int opcode = insn.getOpcode();
	if (opcode == MULTIANEWARRAY) {
	for (BasicValue value : values) {
	if (!BasicValue.INT_VALUE.equals(value)) {
	throw new AnalyzerException(insn, null, BasicValue.INT_VALUE, value);
	}
	}
	} else {
	int i = 0;
	int j = 0;
	if (opcode != INVOKESTATIC && opcode != INVOKEDYNAMIC) {
	Type owner = Type.getObjectType(((MethodInsnNode) insn).owner);
	if (!isSubTypeOf(values.get(i++), newValue(owner))) {
	throw new AnalyzerException(insn, "Method owner", newValue(owner), values.get(0));
	}
	}
	String methodDescriptor =
	(opcode == INVOKEDYNAMIC)
	? ((InvokeDynamicInsnNode) insn).desc
	: ((MethodInsnNode) insn).desc;
	Type[] args = Type.getArgumentTypes(methodDescriptor);
	while (i < values.size()) {
	BasicValue expected = newValue(args[j++]);
	BasicValue actual = values.get(i++);
	if (!isSubTypeOf(actual, expected)) {
	throw new AnalyzerException(insn, "Argument " + j, expected, actual);
	}
	}
	}
	return super.naryOperation(insn, values);
	}

	@Override
	public void returnOperation(
	final AbstractInsnNode insn, final BasicValue value, final BasicValue expected)
	throws AnalyzerException {
	if (!isSubTypeOf(value, expected)) {
	throw new AnalyzerException(insn, "Incompatible return type", expected, value);
	}
	}

	/**
	* Returns whether the given value corresponds to an array reference.
	*
	* @param value a value.
	* @return whether 'value' corresponds to an array reference.
	*/
	protected boolean isArrayValue(final BasicValue value) {
	return value.isReference();
	}

	/**
	* Returns the value corresponding to the type of the elements of the given array reference value.
	*
	* @param objectArrayValue a value corresponding to array of object (or array) references.
	* @return the value corresponding to the type of the elements of 'objectArrayValue'.
	* @throws AnalyzerException if objectArrayValue does not correspond to an array type.
	*/
	protected BasicValue getElementValue(final BasicValue objectArrayValue) throws AnalyzerException {
	return BasicValue.REFERENCE_VALUE;
	}

	/**
	* Returns whether the type corresponding to the first argument is a subtype of the type
	* corresponding to the second argument.
	*
	* @param value a value.
	* @param expected another value.
	* @return whether the type corresponding to 'value' is a subtype of the type corresponding to
	* 'expected'.
	*/
	protected boolean isSubTypeOf(final BasicValue value, final BasicValue expected) {
	return value.equals(expected);
	}
	}

Back to index...