def load_instructions():
file_data = get_file_data()
int_codes = []
instruction = Instruction()
for i in range(len(file_data)):
if (i % 4 == 0):
instruction = Instruction()
instruction.opcode = file_data[i]
elif (i % 3 == 0 and i != 0):
instruction.parameters.append(file_data[i])
int_codes.append(instruction)
else:
instruction.parameters.append(file_data[i])
return int_codes
def parse(self, asm_file):
"""
:param asm_file: .asm source file
:return: parsed instructions
"""
with open(asm_file, 'r') as f:
asm_source = f.read()
# First pass through the instructions.
# Stores all instructions in a list, and builds the symbol table.
instructions_list = []
for raw_instruction in asm_source.split('\n'):
raw_instruction = raw_instruction.strip()
if not raw_instruction: # Pass if empty line
continue
line_type = self.line_type(raw_instruction)
if line_type == 'comment':
instructions_list.append(self.parse_comment(raw_instruction))
elif line_type == 'instruction':
parsed_instruction = Instruction(raw_instruction)
parsed_instruction.addr = self._pc
self._pc += 2 # Since memory is byte-addressable and words are 16-bits
# If we have li, split into lui and ori.
if parsed_instruction.opname == 'li':
parsed_instruction.opname = 'li_lui'
parsed_instruction.opcode = self._codes.get_opcode('lui')
instructions_list.append(parsed_instruction)
# Ori part of instruction
ori_li_instruction = deepcopy(parsed_instruction)
ori_li_instruction.addr = self._pc
self._pc += 2
ori_li_instruction.opname = 'li_ori'
ori_li_instruction.opcode = self._codes.get_opcode('ori')
instructions_list.append(ori_li_instruction)
else:
instructions_list.append(parsed_instruction)
elif line_type == 'directive':
# Needs to be a list since asciiz will return multiple lines of instructions.
directive_list = self.parse_directive_to_list(raw_instruction)
# Stores the first item's address to the symbol table
first_in_mem = directive_list[0]
self._symbol_table[first_in_mem.label] = self._pc
for directive in directive_list:
directive.addr = self._pc
self._pc += 2
instructions_list.append(directive)
else:
assert line_type == 'label'
self.store_label(raw_asm_line=raw_instruction, addr=self._pc)
if len(instructions_list) > self._MAX:
raise MemoryError("Instructions exceeded {}".format(self._MAX))
encoded_instructions = []
for instruction in instructions_list:
encoded_instructions.append(self.encode(instruction))
return encoded_instructions
