private void checkContextWrite(Register reg, Address start, Address end)
			throws ContextChangeException {
		if (changing || !reg.getBaseRegister().equals(getBaseContextRegister())) {
			return;
		}
		CodeManager codeManager = program.getCodeManager();
		codeManager.checkContextWrite(start, end);
	}
Intialize context with default values defined by pspec and cspec.
NOTE: cspec values take precedence
@param lang processor language
@param compilerSpec compiler specification
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/register/ProgramRegisterContextDB.java