/*
JPC: An x86 PC Hardware Emulator for a pure Java Virtual Machine
Release Version 2.4
A project from the Physics Dept, The University of Oxford
Copyright (C) 2007-2010 The University of Oxford
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License version 2 as published by
the Free Software Foundation.
This program 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 for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
Details (including contact information) can be found at:
jpc.sourceforge.net
or the developer website
sourceforge.net/projects/jpc/
Conceived and Developed by:
Rhys Newman, Ian Preston, Chris Dennis
End of licence header
*/
package org.jpc.emulator.memory;
import org.jpc.emulator.processor.Processor;
import org.jpc.emulator.processor.ProcessorException;
/**
* Class that implements an alignment checking skin on another <code>AddressSpace</code>
* instance. Access that are not alignment on the correct granularity will
* trigger a {@link org.jpc.emulator.processor.ProcessorException} with the
* appropriate vector value.
* @author Chris Dennis
*/
public class AlignmentCheckedAddressSpace extends AddressSpace
{
private final AddressSpace addressSpace;
/**
* Constructs an address space wrapping the supplied target.
* @param target address space to be wrapped.
*/
public AlignmentCheckedAddressSpace(AddressSpace target)
{
addressSpace = target;
}
protected Memory getReadMemoryBlockAt(int offset)
{
return addressSpace.getReadMemoryBlockAt(offset);
}
protected Memory getWriteMemoryBlockAt(int offset)
{
return addressSpace.getWriteMemoryBlockAt(offset);
}
protected void replaceBlocks(Memory oldBlock, Memory newBlock)
{
addressSpace.replaceBlocks(oldBlock, newBlock);
}
public int executeReal(Processor cpu, int offset)
{
return addressSpace.executeReal(cpu, offset);
}
public int executeProtected(Processor cpu, int offset)
{
return addressSpace.executeReal(cpu, offset);
}
public int executeVirtual8086(Processor cpu, int offset)
{
return addressSpace.executeReal(cpu, offset);
}
public void clear()
{
addressSpace.clear();
}
public byte getByte(int offset)
{
return addressSpace.getByte(offset);
}
public void setByte(int offset, byte data)
{
addressSpace.setByte(offset, data);
}
/**
* Throws a <code>ProcessorException</code> if the access is not aligned to
* a word (two-byte) boundary.
* @param offset address to be read.
* @return short value read.
*/
public short getWord(int offset)
{
if ((offset & 0x1) != 0)
throw ProcessorException.ALIGNMENT_CHECK_0;
return addressSpace.getWord(offset);
}
/**
* Throws a <code>ProcessorException</code> if the access is not aligned to
* a doubleword (four-byte) boundary.
* @param offset address to be read.
* @return int value read.
*/
public int getDoubleWord(int offset)
{
if ((offset & 0x3) != 0)
throw ProcessorException.ALIGNMENT_CHECK_0;
return addressSpace.getDoubleWord(offset);
}
/**
* Throws a <code>ProcessorException</code> if the access is not aligned to
* a quad-word (eight-byte) boundary.
* @param offset address to be read.
* @return int value read.
*/
public long getQuadWord(int offset)
{
if ((offset & 0x7) != 0)
throw ProcessorException.ALIGNMENT_CHECK_0;
return addressSpace.getQuadWord(offset);
}
/**
* Throws a <code>ProcessorException</code> if the access is not aligned to
* a octa-word (sixteen-byte) boundary.
* @param offset address to be read.
* @return long value read.
*/
public long getLowerDoubleQuadWord(int offset)
{
if ((offset & 0xF) != 0)
throw ProcessorException.ALIGNMENT_CHECK_0;
return addressSpace.getLowerDoubleQuadWord(offset);
}
public long getUpperDoubleQuadWord(int offset)
{
return addressSpace.getUpperDoubleQuadWord(offset);
}
/**
* Throws a <code>ProcessorException</code> if the access is not aligned to
* a word (two-byte) boundary.
* @param offset address to be read.
* @param data value to write.
*/
public void setWord(int offset, short data)
{
if ((offset & 0x1) != 0)
throw ProcessorException.ALIGNMENT_CHECK_0;
addressSpace.setWord(offset, data);
}
/**
* Throws a <code>ProcessorException</code> if the access is not aligned to
* a doubleword (four-byte) boundary.
* @param offset address to be read.
* @param data value to write.
*/
public void setDoubleWord(int offset, int data)
{
if ((offset & 0x3) != 0)
throw ProcessorException.ALIGNMENT_CHECK_0;
addressSpace.setDoubleWord(offset, data);
}
/**
* Throws a <code>ProcessorException</code> if the access is not aligned to
* a quadword (eight-byte) boundary.
* @param offset address to be read.
* @param data value to write.
*/
public void setQuadWord(int offset, long data)
{
if ((offset & 0x7) != 0)
throw ProcessorException.ALIGNMENT_CHECK_0;
addressSpace.setQuadWord(offset, data);
}
/**
* Throws a <code>ProcessorException</code> if the access is not aligned to
* a octa-word (sixteen-byte) boundary.
* @param offset address to be read.
* @param data value to write.
*/
public void setLowerDoubleQuadWord(int offset, long data)
{
if ((offset & 0xF) != 0)
throw ProcessorException.GENERAL_PROTECTION_0;
addressSpace.setLowerDoubleQuadWord(offset, data);
}
public void setUpperDoubleQuadWord(int offset, long data)
{
addressSpace.setUpperDoubleQuadWord(offset, data);
}
public void copyArrayIntoContents(int address, byte[] buffer, int off, int len)
{
addressSpace.copyArrayIntoContents(address, buffer, off, len);
}
public void copyContentsIntoArray(int address, byte[] buffer, int off, int len)
{
addressSpace.copyContentsIntoArray(address, buffer, off, len);
}
public void loadInitialContents(int address, byte[] buf, int off, int len) {
throw new UnsupportedOperationException("Not supported yet.");
}
}