@Test
	public void testFunctionRegParamDiff1() throws Exception {
	
		// program1 has reg param and program2 doesn't.
	
		int transactionID1 = p1.startTransaction("Test Transaction");
		Function function1 = p1.getFunctionManager().getFunctionAt(addr(p1, 0x10048a3));
		Register dr0Reg = p1.getRegister("DR0");
		Variable var1 = new ParameterImpl("variable", new DWordDataType(), dr0Reg, p1);
		function1.insertParameter(0, var1, SourceType.USER_DEFINED);
		p1.endTransaction(transactionID1, true);
	
		AddressSet expectedDiffs = new AddressSet(addr(0x10048a3), addr(0x10048a3));
		checkDiff(expectedDiffs, ProgramDiffFilter.FUNCTION_DIFFS);
	}
Test that ProgramDiff can determine that function parameter types are
different.
Ghidra/Features/Base/src/test.slow/java/ghidra/program/util/ProgramDiff3Test.java