lazycodeblockmemory.java

JPC: x86 PC Hardware Emulator. 牛津大学开发的一个纯JAVA的x86系统结构硬件模拟器。

    }

    private void removeVirtual8086CodeBlockAt(int offset)
    {
        Virtual8086ModeCodeBlock b = virtual8086CodeBuffer[offset];
        if ((b == null) || (b == PLACEHOLDER))
            return;

        virtual8086CodeBuffer[offset] = null;
        int len = b.getX86Length();
        for (int i=offset+1; (i<offset + len) && (i < virtual8086CodeBuffer.length); i++)
        {
            if (virtual8086CodeBuffer[i] == PLACEHOLDER)
                virtual8086CodeBuffer[i] = null;
        }
   
        for (int i=Math.min(offset + len, virtual8086CodeBuffer.length)-1; i>=0; i--)
        {
            if (virtual8086CodeBuffer[i] == null)
            {
                if (i < offset)
                    break;
                else
                    continue;
            }
            if (virtual8086CodeBuffer[i] == PLACEHOLDER)
                continue;

            Virtual8086ModeCodeBlock bb = virtual8086CodeBuffer[i];
            len = bb.getX86Length();

            for (int j=i+1; (j<i+len) && (j<virtual8086CodeBuffer.length); j++)
            {
                if (virtual8086CodeBuffer[j] == null)
                    virtual8086CodeBuffer[j] = PLACEHOLDER;
            }
        }
    }

    private void removeProtectedCodeBlockAt(int offset)
    {
        ProtectedModeCodeBlock b = protectedCodeBuffer[offset];
        if ((b == null) || (b == PLACEHOLDER))
            return;

        protectedCodeBuffer[offset] = null;
        int len = b.getX86Length();
        for (int i=offset+1; (i<offset + len) && (i < protectedCodeBuffer.length); i++)
        {
            if (protectedCodeBuffer[i] == PLACEHOLDER)
                protectedCodeBuffer[i] = null;
        }
   
        for (int i=Math.min(offset + len, protectedCodeBuffer.length)-1; i>=0; i--)
        {
            if (protectedCodeBuffer[i] == null)
            {
                if (i < offset)
                    break;
                else
                    continue;
            }
            if (protectedCodeBuffer[i] == PLACEHOLDER)
                continue;

            ProtectedModeCodeBlock bb = protectedCodeBuffer[i];
            len = bb.getX86Length();

            for (int j=i+1; (j<i+len) && (j<protectedCodeBuffer.length); j++)
            {
                if (protectedCodeBuffer[j] == null)
                    protectedCodeBuffer[j] = PLACEHOLDER;
            }
        }
    }

    private void removeRealCodeBlockAt(int offset)
    {
        RealModeCodeBlock b = realCodeBuffer[offset];
        if ((b == null) || (b == PLACEHOLDER))
            return;

        realCodeBuffer[offset] = null;
        int len = b.getX86Length();
        for (int i=offset+1; (i<offset + len) && (i < realCodeBuffer.length); i++)
        {
            if (realCodeBuffer[i] == PLACEHOLDER)
                realCodeBuffer[i] = null;
        }
   
        for (int i=Math.min(offset + len, realCodeBuffer.length)-1; i>=0; i--)
        {
            if (realCodeBuffer[i] == null)
            {
                if (i < offset)
                    break;
                else
                    continue;
            }
            if (realCodeBuffer[i] == PLACEHOLDER)
                continue;

            RealModeCodeBlock bb = realCodeBuffer[i];
            len = bb.getX86Length();

            for (int j=i+1; (j<i+len) && (j<realCodeBuffer.length); j++)
            {
                if (realCodeBuffer[j] == null)
                    realCodeBuffer[j] = PLACEHOLDER;
            }
        }
    }

    public void setVirtual8086CodeBlockAt(int offset, Virtual8086ModeCodeBlock block)
    {
        removeVirtual8086CodeBlockAt(offset);
        if (block == null)
            return;

        virtual8086CodeBuffer[offset] = block;
        int len = block.getX86Length();
        for (int i=offset+1; (i<offset+len) && (i<virtual8086CodeBuffer.length); i++)
        {
            if (virtual8086CodeBuffer[i] == null)
                virtual8086CodeBuffer[i] = PLACEHOLDER;
        }
    }

    public void setProtectedCodeBlockAt(int offset, ProtectedModeCodeBlock block)
    {
        removeProtectedCodeBlockAt(offset);
        if (block == null)
            return;

        protectedCodeBuffer[offset] = block;
        int len = block.getX86Length();
        for (int i=offset+1; (i<offset+len) && (i<protectedCodeBuffer.length); i++)
        {
            if (protectedCodeBuffer[i] == null)
                protectedCodeBuffer[i] = PLACEHOLDER;
        }
    }

    public void setRealCodeBlockAt(int offset, RealModeCodeBlock block)
    {
        removeRealCodeBlockAt(offset);
        if (block == null)
            return;

        realCodeBuffer[offset] = block;
        int len = block.getX86Length();
        for (int i=offset+1; (i<offset+len) && (i<realCodeBuffer.length); i++)
        {
            if (realCodeBuffer[i] == null)
                realCodeBuffer[i] = PLACEHOLDER;
        }
    }

    protected void regionAltered(int start, int end)
    {
        for (int i=end; i>=0; i--)
        {
            RealModeCodeBlock b = realCodeBuffer[i];
            if (b == null) 
            {
                if (i < start)
                    break;
                else
                    continue;
            }

            if (b == PLACEHOLDER)
                continue;
            
            if (!b.handleMemoryRegionChange(start, end))
                removeRealCodeBlockAt(i);
        } 

        for (int i=end; i>=0; i--)
        {
            ProtectedModeCodeBlock b = protectedCodeBuffer[i];
            if (b == null) 
            {
                if (i < start)
                    break;
                else
                    continue;
            }

            if (b == PLACEHOLDER)
                continue;
            
            if (!b.handleMemoryRegionChange(start, end))
                removeProtectedCodeBlockAt(i);
        } 

        for (int i=end; i>=0; i--)
        {
            Virtual8086ModeCodeBlock b = virtual8086CodeBuffer[i];
            if (b == null) 
            {
                if (i < start)
                    break;
                else
                    continue;
            }

            if (b == PLACEHOLDER)
                continue;
            
            if (!b.handleMemoryRegionChange(start, end))
                removeVirtual8086CodeBlockAt(i);
        } 
    }

    public void copyContentsFrom(int address, byte[] buf, int off, int len)
    {
        super.copyContentsFrom(address, buf, off, len);
        regionAltered(address, address + len - 1);
    }

    public void setByte(int offset, byte data)
    {
        if (super.getByte(offset) == data)
            return;
        super.setByte(offset, data);
        regionAltered(offset, offset);
    }

    public void setWord(int offset, short data)
    {
        if (super.getWord(offset) == data)
            return;
        super.setWord(offset, data);
        regionAltered(offset, offset + 1);
    }

    public void setDoubleWord(int offset, int data)
    {
        if (super.getDoubleWord(offset) == data)
            return;
        super.setDoubleWord(offset, data);
        regionAltered(offset, offset + 3);
    }

    public void clear()
    {
	constructCodeBlocksArray();
	super.clear();
    }

    public String toString()
    {
        return "LazyCodeBlockMemory["+getSize()+"]";
    }

        
    public static void dispose()
    {
        if (codeBlockManager != null)
            codeBlockManager.dispose();
        codeBlockManager = null;
    }
}