def semantic(ast, iNES=False, cart=None):
if cart == None:
cart = Cartridge()
labels = get_labels(ast)
address = 0
# translate statments to opcode
for leaf in ast:
if leaf["type"] == "S_RS":
labels[leaf["children"][0]["value"]] = cart.rs
cart.rs += get_value(leaf["children"][2])
elif leaf["type"] == "S_DIRECTIVE":
directive = leaf["children"][0]["value"]
if len(leaf["children"]) == 2:
argument = get_value(leaf["children"][1], labels)
else:
argument = leaf["children"][1:]
if directive in directive_list:
directive_list[directive](argument, cart)
else:
raise Exception("UNKNOW DIRECTIVE")
else:
if leaf["type"] in ["S_IMPLIED", "S_ACCUMULATOR"]:
instruction = leaf["children"][0]["value"]
address = False
elif leaf["type"] == "S_RELATIVE":
instruction = leaf["children"][0]["value"]
address = get_value(leaf["children"][1], labels)
elif leaf["type"] == "S_IMMEDIATE_WITH_MODIFIER":
instruction = leaf["children"][0]["value"]
modifier = leaf["children"][1]["value"]
address = get_value(leaf["children"][3], labels)
if modifier == "#LOW":
address = address & 0x00FF
elif modifier == "#HIGH":
address = (address & 0xFF00) >> 8
elif leaf["type"] in [
"S_RELATIVE",
"S_IMMEDIATE",
"S_ZEROPAGE",
"S_ABSOLUTE",
"S_ZEROPAGE_X",
"S_ZEROPAGE_Y",
"S_ABSOLUTE_X",
"S_ABSOLUTE_Y",
]:
instruction = leaf["children"][0]["value"]
address = get_value(leaf["children"][1], labels)
elif leaf["type"] in ["S_INDIRECT_X", "S_INDIRECT_Y"]:
instruction = leaf["children"][0]["value"]
address = get_value(leaf["children"][2], labels)
address_mode = address_mode_def[leaf["type"]]["short"]
opcode = opcodes[instruction][address_mode]
if address_mode != "sngl":
if "rel" == address_mode:
address = 126 + (address - cart.pc)
if address == 128:
address = 0
elif address < 128:
address = address | 0b10000000
elif address > 128:
address = address & 0b01111111
if address_mode_def[leaf["type"]]["size"] == 2:
cart.append_code([opcode, address])
else:
arg1 = address & 0x00FF
arg2 = (address & 0xFF00) >> 8
cart.append_code([opcode, arg1, arg2])
else:
cart.append_code([opcode])
nes_code = []
if iNES:
return cart.get_ines_code()
else:
return cart.get_code()
