Kshitij
bdfc8ea1b2
python) - Removed class, there's individual functions now - No more "self", that's too much work for practical exam - Removed expand_macro function, it was unnecessary - Overall refinement for better understanding - Added comments
101 lines
3.0 KiB
Python
101 lines
3.0 KiB
Python
# Assignment-A2 - Two-pass macro processor code in Python
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# BEGINNING OF CODE
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# Required databases
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macro_definition_table = {} # Storing all macro definitions with their names
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macro_name_table = {} # Storing macro names and their index
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##########################################################################
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def process_pass1(source_code):
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mdt_index = 0
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macro_definition = []
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current_macro_name = None
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inside_macro = False
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for line in source_code:
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tokens = line.strip().split() # store each word of the line of source code
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if (not tokens): # skips blank lines
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continue
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if (tokens[0] == 'MACRO'): # beginning of macro definition
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inside_macro = True
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continue
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if (inside_macro == True and tokens[0] == 'MEND'): # if end of macro is reached
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inside_macro = False
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macro_definition_table[current_macro_name] = macro_definition[:]
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macro_name_table[current_macro_name] = mdt_index
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mdt_index += len(macro_definition)
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macro_definition = []
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current_macro_name = None
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continue
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if (inside_macro == True): # processing contents of macro
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if (not current_macro_name):
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current_macro_name = tokens[0]
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macro_definition.append(line.strip())
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##########################################################################
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def process_pass2(source_code):
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output = []
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inside_macro = False
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for line in source_code:
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tokens = line.strip().split()
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if (not tokens or tokens[0] == 'MACRO'): # skipping spaces, MACRO and MEND keywords
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inside_macro = True
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continue
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elif (tokens[0] == 'MEND'):
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inside_macro = False
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continue
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if inside_macro:
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continue
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macro_name = tokens[0]
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if macro_name in macro_name_table: # expand macro from source code
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args = tokens[1:]
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macro_def = macro_definition_table[macro_name]
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for expanded_line in macro_def:
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for i, arg in enumerate(args):
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expanded_line = expanded_line.replace(f"&ARG{i+1}", arg)
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output.append(expanded_line)
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else: # append line if not a macro
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output.append(line.strip())
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return output
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##########################################################################
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def display():
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print("Macro Name Table (MNT):")
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for name, index in macro_name_table.items():
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print(f"Macro Name: {name} | Index: {index}")
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print("Macro Definition Table (MDT):")
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for name, definition in macro_definition_table.items():
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print(f"Macro: {name}")
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for line in definition:
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print(f"\t{line}")
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##########################################################################
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source_code = [
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"MACRO",
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"INCR &ARG1",
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"ADD &ARG1, ONE",
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"MEND",
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"MACRO",
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"DECR &ARG1",
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"SUB &ARG1, ONE",
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"MEND",
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"START",
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"INCR A",
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"DECR B",
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"END"
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]
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##########################################################################
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process_pass1(source_code)
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display()
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print("PASS 2:")
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expanded_code = process_pass2(source_code)
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for i in expanded_code:
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print(i)
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# END OF CODE
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