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modal/Jack-Hack VM.py

Forked from jweissbock/Jack-Hack VM.py
Created February 22, 2011 15:08
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Jack-Hack VM.py
import glob
# declare types of commands
C_ARITMETIC = object()
C_PUSH = object()
C_POP = object()
C_LABEL = object()
C_GOTO = object()
C_IF = object()
C_FUNCTION = object()
C_RETURN = object()
C_CALL = object()
C_ERROR = object()
class CodeWriter:
file = None # file to be writing to
fileName = None
compare = 1 # the number of equalities
def __init__(self, name):
self.file = open(name, 'w')
self.fileName = name.strip()
def __del__(self):
self.file.close()
def WriteAritmetic(self, arg1):
# plus or minus
if arg1 in ['add', 'sub', 'and', 'or']:
if arg1 == 'add': line = 'D=D+M'
elif arg1 == 'sub': line = 'D=M-D'
elif arg1 == 'and': line = 'D=D&M'
elif arg1 == 'or': line = 'D=D|M'
self.file.write("@SP\n") #A=0, M[0]=258
self.file.write("M=M-1\n") #M[0]=258-1
self.file.write("A=M\n") #A=257
self.file.write("D=M\n") #D=M[257] (8)
self.file.write("A=A-1\n") #A=256
self.file.write("%s\n" % (line, ))
self.file.write("M=D\n") #M[256]=D
self.file.write("D=A+1\n") #A=257
self.file.write("@SP\n")
self.file.write("M=D\n")
return True
# unary operations
elif arg1 in ['neg', 'not']:
line = 'M=-M' if arg1 == 'neg' else 'M=!M'
self.file.write("@SP\n")
self.file.write("M=M-1\n")
self.file.write("A=M\n")
self.file.write("%s\n" % (line, ))
self.file.write("D=A+1\n")
self.file.write("@SP\n")
self.file.write("M=D\n")
# in case they are equal
elif arg1 in ['eq', 'lt', 'gt']:
if arg1 == "eq":
line = "D;JEQ"
elif arg1 == "lt":
line = "D;JLT"
elif arg1 == "gt":
line = "D;JGT"
self.file.write("@SP\n")
self.file.write("M=M-1\n")
self.file.write("A=M\n")
self.file.write("D=M\n")
self.file.write("A=A-1\n")
self.file.write("D=M-D\n")
self.file.write("@EQ%d\n" % (self.compare, ))
self.file.write("%s\n" % (line, ))
self.file.write("@0\n")
self.file.write("D=-A\n")
self.file.write("@SP\n")
self.file.write("A=M\n")
self.file.write("M=D\n")
self.file.write("@SP\n")
self.file.write("M=M+1\n")
self.file.write("@doneEQ%d\n" % (self.compare, ))
self.file.write("0;JMP\n")
self.file.write("(EQ%d)\n" % (self.compare, ))
self.file.write("@1\n")
self.file.write("D=A\n")
self.file.write("@SP\n")
self.file.write("A=M\n")
self.file.write("M=D\n")
self.file.write("@SP\n")
self.file.write("M=M+1\n")
self.file.write("(doneEQ%d)\n" % (self.compare, ))
self.compare += 1
return False
def WritePushPop(self, type, segment, index):
# deal with the value
value = 0
if segment == "constant":
self.file.write("@%s\n" % (str(index), ))
self.file.write("D=A\n")
elif segment in ['local', 'argument', 'this', 'that']:
if segment == 'local': key = "LCL"
elif segment == 'argument': key = "ARG"
elif segment == 'this': key = 'THIS'
elif segment == 'that': key = 'THAT'
self.file.write("@%s\n" % (str(key), ))
self.file.write("D=A\n")
self.file.write("@%s\n" % (str(index), ))
self.file.write("D=D+M\n")
elif segment in ['pointer', 'temp']:
if segment == 'pointer': base = 3
elif segment == 'temp': base = 5
self.file.write("@%s\n" % (base, ))
self.file.write("D=A\n")
self.file.write("@%s\n" % (index, ))
self.file.write("D=D+A\n")
elif segment in ['static']:
self.file.write("@%s.%s\n" % (self.fileName[:-4], index))
self.file.write("D=M\n")
if type is C_PUSH:
self.file.write("@SP\n")
self.file.write("A=M\n")
self.file.write("M=D\n")
self.file.write("D=A+1\n")
self.file.write("@SP\n")
self.file.write("M=D\n")
return True
elif type is C_POP:
self.file.write("@R13\n")
self.file.write("M=D\n")
self.file.write("@SP\n")
self.file.write("A=M-1\n")
self.file.write("D=M\n")
self.file.write("@R13\n")
self.file.write("A=M\n")
self.file.write("M=D\n")
return True
return False
class VM:
file = None # stores the file(s) to open
fileWriter = None # the new file to write to
dir = None # name of the directory
# get the file
def __getFile(self):
var = raw_input("What is the file name/directory: ")
# if ends in .vm just one file, otherwise directory
if var[len(var)-3:len(var)] == '.vm':
self.file = [var]
self.dir = var[:-3]
else:
# directory, check if ends in /, otherwise add
if var[-1] <> "/":
self.dir = var
var = "%s/" % var
else:
self.dir = var[:-1]
# glob through them all for .vm files
self.file = glob.glob(var + "*.vm")
return True
# check if the line is actually code
def __isCode(self, line):
output = line.lstrip(" ")
if output.startswith("//"): # check if it is a comment
return False
elif output.startswith('\n'): # check if it just a new line
return False
else:
return True
# parse the line
def __parseLine(self, line):
line = line.strip(" ")
line = line.rstrip("\n")
line = line[:line.find("//")]
return line.lower()
# define the command type
def __commandType(self, line):
if line.find(" ") > -1:
seg1 = line[:line.find(" ")].lower()
else:
seg1 = line
if seg1 == "push":
return C_PUSH
elif seg1 == "pop":
return C_POP
elif seg1 in ['add', 'sub', 'neg', 'eq', 'lt', 'gt', 'and', 'or', 'not']:
return C_ARITMETIC
else:
return C_ERROR
# get the first arguement
def __arg1(self, input):
if input.find(" ") < 0:
return input
else:
input = input[input.find(" ")+1:]
return input[:input.find(" ")]
# def get the second arguement
def __arg2(self, input):
input = input[input.find(" ")+1:]
return input[input.find(" ")+1:]
# go through the file and do the cool shit
def __outFile(self, inFile):
# open new file
input = open(inFile, 'r')
# loop through
for f in input:
# check if it is a comment or a newline
if not self.__isCode(f):
continue
# parse the line
f = self.__parseLine(f)
# what type of line it is
type = self.__commandType(f)
# write a line
if type is C_ARITMETIC:
self.fileWriter.WriteAritmetic(self.__arg1(f))
elif type in [C_PUSH, C_POP]:
self.fileWriter.WritePushPop(type, self.__arg1(f), self.__arg2(f))
# boot strap the VM
def __init__(self):
# get the files to open to
print "Getting files..."
self.__getFile()
# the file writer class
self.fileWriter = CodeWriter(self.dir + ".asm")
# foreach file out
print "Writing files..."
for f in self.file:
self.__outFile(f)
# destroy the filewrite - to close the file
print "Done"
del self.fileWriter
# main execution of the code
if __name__ == "__main__":
aVM = VM()
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