com.sun.jdo.api.persistence.enhancer.classfile.InsnConstOp Maven / Gradle / Ivy
/*
* Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package com.sun.jdo.api.persistence.enhancer.classfile;
import java.io.PrintStream;
/**
* An instruction which requires a single constant from the constant
* pool as an immediate operand
*/
public class InsnConstOp extends Insn {
/* The constant from the constant pool */
private ConstBasic constValue;
/* public accessors */
public int nStackArgs() {
int n = VMOp.ops[opcode()].nStackArgs();
if (n >= 0)
return n;
switch (opcode()) {
case opc_putstatic:
case opc_putfield:
{
ConstFieldRef fld = (ConstFieldRef) constValue;
String sig = fld.nameAndType().signature().asString();
if (sig.equals("J") || sig.equals("D"))//NOI18N
return (opcode() == opc_putfield) ? 3 : 2;
return (opcode() == opc_putfield) ? 2 : 1;
}
case opc_invokevirtual:
case opc_invokespecial:
case opc_invokestatic:
/* handle interface invoke too */
case opc_invokeinterface:
{
ConstBasicMemberRef meth = (ConstBasicMemberRef) constValue;
String sig = meth.nameAndType().signature().asString();
int nMethodArgWords = Descriptor.countMethodArgWords(sig);
return nMethodArgWords +
((opcode() == opc_invokestatic) ? 0 : 1);
}
default:
throw new InsnError("unexpected variable opcode");//NOI18N
}
}
public int nStackResults() {
int n = VMOp.ops[opcode()].nStackResults();
if (n >= 0)
return n;
switch (opcode()) {
case opc_getstatic:
case opc_getfield:
{
ConstFieldRef fld = (ConstFieldRef) constValue;
String sig = fld.nameAndType().signature().asString();
if (sig.equals("J") || sig.equals("D"))//NOI18N
return 2;
return 1;
}
case opc_invokevirtual:
case opc_invokespecial:
case opc_invokestatic:
/* handle interface invoke too */
case opc_invokeinterface:
{
ConstBasicMemberRef meth = (ConstBasicMemberRef) constValue;
return Descriptor.countMethodReturnWords(
meth.nameAndType().signature().asString());
}
default:
throw new InsnError("unexpected variable opcode");//NOI18N
}
}
public String argTypes() {
switch (opcode()) {
case opc_putstatic:
case opc_putfield:
{
ConstFieldRef fld = (ConstFieldRef) constValue;
String sig = fld.nameAndType().signature().asString();
if (opcode() == opc_putstatic)
return sig;
else
return descriptorTypeOfObject(fld) + sig;
}
case opc_invokevirtual:
case opc_invokespecial:
case opc_invokestatic:
/* handle interface invoke too */
case opc_invokeinterface:
{
ConstBasicMemberRef meth = (ConstBasicMemberRef) constValue;
String argSig =
Descriptor.extractArgSig(meth.nameAndType().signature().asString());
if (opcode() == opc_invokestatic)
return argSig;
else
return descriptorTypeOfObject(meth) + argSig;
}
default:
return VMOp.ops[opcode()].argTypes();
}
}
public String resultTypes() {
switch (opcode()) {
case opc_invokevirtual:
case opc_invokespecial:
case opc_invokestatic:
/* handle interface invoke too */
case opc_invokeinterface:
{
ConstBasicMemberRef meth = (ConstBasicMemberRef) constValue;
String resultSig = Descriptor.extractResultSig(
meth.nameAndType().signature().asString());
if (resultSig.equals("V"))//NOI18N
return "";//NOI18N
return resultSig;
}
case opc_getstatic:
case opc_getfield:
{
ConstFieldRef fld = (ConstFieldRef) constValue;
return fld.nameAndType().signature().asString();
}
case opc_ldc:
case opc_ldc_w:
case opc_ldc2_w:
{
ConstValue constVal = (ConstValue) constValue;
return constVal.descriptor();
}
default:
return VMOp.ops[opcode()].resultTypes();
}
}
public boolean branches() {
/* invokes don't count as a branch */
return false;
}
/**
* Return the constant pool entry which is the immediate operand
*/
public ConstBasic value() {
return constValue;
}
/**
* Modify the referenced constant
*/
public void setValue(ConstBasic newValue) {
checkConstant(newValue);
constValue = newValue;
}
/* package local methods */
void print (PrintStream out, int indent) {
ClassPrint.spaces(out, indent);
out.println(offset() + " " + opName(opcode()) + " pool(" + //NOI18N
constValue.getIndex() + ")");//NOI18N
}
int store(byte[] buf, int index) {
if (opcode() == opc_ldc && !isNarrowldc())
buf[index++] = (byte) opc_ldc_w;
else
buf[index++] = (byte) opcode();
int constIndex = constValue.getIndex();
if (size() == 3)
buf[index++] = (byte) (constIndex >> 8);
buf[index++] = (byte)(constIndex & 0xff);
return index;
}
int size() {
return isNarrowldc() ? 2 : 3;
}
private boolean isNarrowldc() {
return (opcode() == opc_ldc && constValue.getIndex() < 256);
}
InsnConstOp (int theOpcode, ConstBasic theOperand) {
this(theOpcode, theOperand, NO_OFFSET);
}
InsnConstOp (int theOpcode, ConstBasic theOperand, int pc) {
super(theOpcode, pc);
constValue = theOperand;
checkConstant(theOperand);
if (theOpcode == opc_invokeinterface)
throw new InsnError("attempt to create an " + opName(theOpcode) +//NOI18N
" as an InsnConstOp instead of InsnInterfaceInvoke");//NOI18N
}
/* used only by InsnInterfaceInvoke, to make sure that opc_invokeinterface cannot
* come through the wrong path and miss its extra nArgsOp */
InsnConstOp (int theOpcode, ConstInterfaceMethodRef theOperand, int pc) {
super(theOpcode, pc);
constValue = theOperand;
checkConstant(theOperand);
}
private void checkConstant (ConstBasic operand) {
switch(opcode()) {
case opc_ldc:
case opc_ldc_w:
case opc_ldc2_w:
/* ConstValue */
if (operand == null ||
(! (operand instanceof ConstValue)))
throw new InsnError ("attempt to create an " + opName(opcode()) +//NOI18N
" without a ConstValue operand");//NOI18N
break;
case opc_getstatic:
case opc_putstatic:
case opc_getfield:
case opc_putfield:
/* ConstFieldRef */
if (operand == null ||
(! (operand instanceof ConstFieldRef)))
throw new InsnError ("attempt to create an " + opName(opcode()) +//NOI18N
" without a ConstFieldRef operand");//NOI18N
break;
case opc_invokevirtual:
case opc_invokespecial:
case opc_invokestatic:
/* ConstMethodRef */
if (operand == null ||
(! (operand instanceof ConstMethodRef)))
throw new InsnError ("attempt to create an " + opName(opcode()) +//NOI18N
" without a ConstMethodRef operand");//NOI18N
break;
case opc_invokeinterface:
/* ConstInterfaceMethodRef */
if (operand == null ||
(! (operand instanceof ConstInterfaceMethodRef)))
throw new InsnError("Attempt to create an " + opName(opcode()) +//NOI18N
" without a ConstInterfaceMethodRef operand");//NOI18N
break;
case opc_new:
case opc_anewarray:
case opc_checkcast:
case opc_instanceof:
/* ConstClass */
if (operand == null ||
(! (operand instanceof ConstClass)))
throw new InsnError ("attempt to create an " + opName(opcode()) +//NOI18N
" without a ConstClass operand");//NOI18N
break;
default:
throw new InsnError ("attempt to create an " + opName(opcode()) +//NOI18N
" with a constant operand");//NOI18N
}
}
private final String descriptorTypeOfObject(ConstBasicMemberRef memRef) {
String cname = memRef.className().className().asString();
return "L" + cname + ";";//NOI18N
}
}
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