private int ComputeJump(int addr, LabelInfo info)
{
if (info.isRelative)
{
//Determine distance and direction
int delta = addr - info.startByte;
//We can't insert, because that would be destructive to all following labels and jumps
if (delta > 127 || delta < -128)
{
ErrorMsg("Realtive Jump out of range (-128 to 127)");
}
return (delta & 0xFF);
}
else
{
return addr;
}
}
private void ResolveLabel(int addr, LabelInfo info)
{
//Assume size has been allocated
addr = ComputeJump(addr, info);
if(info.isRelative)
{
rom[info.labelOffset] = (Byte)addr;
}
else
{
rom[info.labelOffset] = (Byte)((addr >> 8) & 0xFF);
rom[info.labelOffset + 1] = (Byte)(addr & 0xFF);
}
String bs = "";
for (int i = info.startByte; i < info.endByte; ++i)
{
bs += "0x" + rom[i].ToString("X2");
if (i < (info.endByte - 1))
{
bs += " ";
}
}
byteLines[info.byteStringIndex] = bs;
}
public void EnterJump(GBASMParser.JumpContext context)
{
PrintLine("Label Dereference");
String label = context.GetText();
LabelInfo l = new LabelInfo();
OffsetInfo o;
l.startByte = rom.Count;
l.isRelative = currentInst.op == Instructions.JR;
o = currentInst.GetCurrentOffset();
l.labelOffset = l.startByte + o.total; //This will be 0 if no src is encoded
l.endByte = l.labelOffset + ((l.isRelative) ? 1 : 2);
l.byteStringIndex = byteLines.Count;
if (jumpAddressIndex.ContainsKey(label))
{
SetArgVal((Int16)ComputeJump(jumpAddressIndex[label], l));
}
else
{
SetArgVal(0);
//CALCULATE SPACE REQUIRED
if(!unProcessedJumpLabels.ContainsKey(label))
{
unProcessedJumpLabels.Add(label, new List<LabelInfo>());
}
//An arg size of NONE should not effect current address calculations
//SRC should always be set before DST is set
unProcessedJumpLabels[label].Add(l);
}
switch (currentInst.op)
{
case Instructions.JR:
SetArgLoc(Locations.IMM);
break;
case Instructions.JP:
default:
SetArgLoc(Locations.WIDE_IMM);
break;
}
}