void IMemoryBus.RemoveMirroring(IMemoryMirroring mirroring)
{
MemoryMirroring mirroringToRemove = this.mirroringsArray.FirstOrDefault(m =>
m.SourceStartAddress == mirroring.SourceStartAddress &&
m.SourceSize == mirroring.SourceSize &&
m.MirrorStartAddress == mirroring.MirrorStartAddress &&
m.MirrorEndAddress == mirroring.MirrorEndAddress);
if (mirroringToRemove != null)
{
this.mirrorings.Remove(mirroringToRemove);
this.mirroringsArray = this.mirrorings.ToArray();
}
}
private IMemoryMappedDevice GetDeviceAtAddress(ref int address)
{
// This method is on a very hot path - use arrays instead of List<T>, indexed loops instead
// of foreach or LINQ, and inline as much as possible. Improves perf by ~40%.
MemoryMapping activeMapping = null;
for (int i = 0; i < this.mappingsArray.Length; i++)
{
MemoryMapping mapping = this.mappingsArray[i];
if (mapping.StartAddress <= address && mapping.EndAddress >= address)
{
activeMapping = mapping;
break;
}
}
if (activeMapping == null)
{
// If we weren't able to find a mapping for the address, check to see if the address is in a mirrored range
MemoryMirroring activeMirroring = null;
for (int i = 0; i < this.mirroringsArray.Length; i++)
{
MemoryMirroring mirroring = this.mirroringsArray[i];
if (mirroring.MirrorStartAddress <= address && mirroring.MirrorEndAddress >= address)
{
activeMirroring = mirroring;
break;
}
}
if (activeMirroring != null)
{
// Calculate the base address and try to find a mapping again
address = activeMirroring.SourceStartAddress + ((address - activeMirroring.MirrorStartAddress) % activeMirroring.SourceSize);
for (int i = 0; i < this.mappingsArray.Length; i++)
{
MemoryMapping mapping = this.mappingsArray[i];
if (mapping.StartAddress <= address && mapping.EndAddress >= address)
{
activeMapping = mapping;
break;
}
}
}
}
return(activeMapping?.Device);
}
IMemoryMirroring IMemoryBus.SetMirroringRange(int sourceStartAddress, int sourceEndAddress, int mirrorStartAddress, int mirrorEndAddress)
{
int sourceSize = (sourceEndAddress - sourceStartAddress) + 1;
int mirrorSize = (mirrorEndAddress - mirrorStartAddress) + 1;
if (mirrorSize % sourceSize != 0)
{
throw new InvalidOperationException("Size of mirrored range must be a multiple of size of source range!");
}
MemoryMirroring mirroring = new MemoryMirroring(sourceStartAddress, sourceSize, mirrorStartAddress, mirrorEndAddress);
this.mirrorings.Add(mirroring);
this.mirroringsArray = this.mirrorings.ToArray();
return(mirroring);
}
