public void updateLatestWrite(ReadIncOperation riop)
	{
		ReadIncOperation riop_var_wriop = null;
		for (String var : GlobalData.VARSET)	// variable by variable
		{
			riop_var_wriop = riop.getLatestWriteMap().getLatestWrite(var);
			if (riop_var_wriop != null)
				if (this.getLatestWrite(var) == null || this.getLatestWrite(var).getWid() < riop_var_wriop.getWid())
					this.latestWriteMap.put(var, riop_var_wriop);	// update to the most latest one 
		}
		
		if (riop.isWriteOp() && ! riop.getWritetoOrder().isEmpty())	// there is some READ reads from @param riop
		{
			String var = riop.getVariable();
			if (this.getLatestWrite(var) == null)
				this.latestWriteMap.put(var, riop);
			else if (this.getLatestWrite(var).getWid() < riop.getWid())
				this.latestWriteMap.put(var, riop);
		}
	}