I need to create a FSMD Simulator in Python, but I'm having problems with the ending state.
The machine is reaching its final state at cycle 22 when testing a machine for computing gcd, but running my codes I get the output of 21 cycles, where the final value of the variables are 4 and 4. At cycle 22, the final value of the variables must be 0 and 0.
The machine is reaching its final state at cycle 22 when testing a machine for computing gcd, but running my codes I get the output of 21 cycles, where the final value of the variables are 4 and 4. At cycle 22, the final value of the variables must be 0 and 0.
import sys
import xmltodict
print("Welcome to the FSMD simulator! - Version ?? - Designed by ??")
if len(sys.argv) < 3:
print('Too few arguments.')
sys.exit(-1)
elif (len(sys.argv) >4):
print('Too many arguments.')
sys.exit(-1)
iterations = int(sys.argv[1])
#Parsing the FSMD description file
with open(sys.argv[2]) as fd:
fsmd_des = xmltodict.parse(fd.read())
#Parsing the stimuli file
fsmd_stim = {}
if len(sys.argv) == 4:
with open(sys.argv[3]) as fd:
fsmd_stim = xmltodict.parse(fd.read())
print("\n--FSMD description--")
#
# Description:
# The 'states' variable of type 'list' contains the list of all states names.
#
states = fsmd_des['fsmddescription']['statelist']['state']
print("States:")
for state in states:
print(' ' + state)
#
# Description:
# The 'initial_state' variable of type 'string' contains the initial_state name.
#
initial_state = fsmd_des['fsmddescription']['initialstate']
print("Initial state:")
print(' ' + initial_state)
#
# Description:
# The 'inputs' variable of type 'dictionary' contains the list of all inputs
# names and value. The default value is 0.
#
inputs = {}
if(fsmd_des['fsmddescription']['inputlist'] is None):
inputs = {}
#No elements
else:
if type(fsmd_des['fsmddescription']['inputlist']['input']) is str:
# One element
inputs[fsmd_des['fsmddescription']['inputlist']['input']] = 0
else:
# More elements
for input_i in fsmd_des['fsmddescription']['inputlist']['input']:
inputs[input_i] = 0
print("Inputs:")
for input_i in inputs:
print(' ' + input_i)
#
# Description:
# The 'variables' variable of type 'dictionary' contains the list of all variables
# names and value. The default value is 0.
#
variables = {}
if(fsmd_des['fsmddescription']['variablelist'] is None):
variables = {}
#No elements
else:
if type(fsmd_des['fsmddescription']['variablelist']['variable']) is str:
# One element
variables[fsmd_des['fsmddescription']['variablelist']['variable']] = 0
else:
# More elements
for variable in fsmd_des['fsmddescription']['variablelist']['variable']:
variables[variable] = 0
print("Variables:")
for variable in variables:
print(' ' + variable)
#
# Description:
# The 'operations' variable of type 'dictionary' contains the list of all the
# defined operations names and expressions.
#
operations = {}
if(fsmd_des['fsmddescription']['operationlist'] is None):
operations = {}
#No elements
else:
for operation in fsmd_des['fsmddescription']['operationlist']['operation']:
if type(operation) is str:
# Only one element
operations[fsmd_des['fsmddescription']['operationlist']['operation']['name']] = \
fsmd_des['fsmddescription']['operationlist']['operation']['expression']
break
else:
# More than 1 element
operations[operation['name']] = operation['expression']
print("Operations:")
for operation in operations:
print(' ' + operation + ' : ' + operations[operation])
#
# Description:
# The 'conditions' variable of type 'dictionary' contains the list of all the
# defined conditions names and expressions.
#
conditions = {}
if(fsmd_des['fsmddescription']['conditionlist'] is None):
conditions = {}
#No elements
else:
for condition in fsmd_des['fsmddescription']['conditionlist']['condition']:
if type(condition) is str:
#Only one element
conditions[fsmd_des['fsmddescription']['conditionlist']['condition']['name']] = fsmd_des['fsmddescription']['conditionlist']['condition']['expression']
break
else:
#More than 1 element
conditions[condition['name']] = condition['expression']
print("Conditions:")
for condition in conditions:
print(' ' + condition + ' : ' + conditions[condition])
#
# Description:
# The 'fsmd' variable of type 'dictionary' contains the list of dictionaries,
# one per state, with the fields 'condition', 'instruction', and 'nextstate'
# describing the FSMD transition table.
#
fsmd = {}
for state in states:
fsmd[state] = []
for transition in fsmd_des['fsmddescription']['fsmd'][state]['transition']:
if type(transition) is str:
#Only one element
fsmd[state].append({'condition': fsmd_des['fsmddescription']['fsmd'][state]['transition']['condition'],
'instruction': fsmd_des['fsmddescription']['fsmd'][state]['transition']['instruction'],
'nextstate': fsmd_des['fsmddescription']['fsmd'][state]['transition']['nextstate']})
break
else:
#More than 1 element
fsmd[state].append({'condition' : transition['condition'],
'instruction' : transition['instruction'],
'nextstate' : transition['nextstate']})
print("FSMD transitions table:")
for state in fsmd:
print(' ' + state)
for transition in fsmd[state]:
print(' ' + 'nextstate: ' + transition['nextstate'] + ', condition: ' + transition['condition'] + ', instruction: ' + transition['instruction'])
#
# Description:
# This function executes a Python compatible operation passed as string
# on the operands stored in the dictionary 'inputs'
#
def execute_setinput(operation):
operation_clean = operation.replace(' ', '')
operation_split = operation_clean.split('=')
target = operation_split[0]
expression = operation_split[1]
inputs[target] = eval(expression, {'__builtins__': None}, inputs)
return
#
# Description:
# This function executes a Python compatible operation passed as string
# on the operands stored in the dictionaries 'variables' and 'inputs'
#
def execute_operation(operation):
operation_clean = operation.replace(' ', '')
operation_split = operation_clean.split('=')
target = operation_split[0]
expression = operation_split[1]
variables[target] = eval(expression, {'__builtins__': None}, merge_dicts(variables, inputs))
return
#
# Description:
# This function executes a list of operations passed as string and spaced by
# a single space using the expression defined in the dictionary 'operations'
#
def execute_instruction(instruction):
if instruction == 'NOP' or instruction == 'nop':
return
instruction_split = instruction.split(' ')
for operation in instruction_split:
execute_operation(operations[operation])
return
#
# Description:
# This function evaluates a Python compatible boolean expressions of
# conditions passed as string using the conditions defined in the variable 'conditions'
# and using the operands stored in the dictionaries 'variables' and 'inputs
# It returns True or False
#
def evaluate_condition(condition):
if condition == 'True' or condition=='true' or condition == 1:
return True
if condition == 'False' or condition=='false' or condition == 0:
return False
condition_explicit = condition
for element in conditions:
condition_explicit = condition_explicit.replace(element, conditions[element])
#print('----' + condition_explicit)
return eval(condition_explicit, {'__builtins__': None}, merge_dicts(variables, inputs))
#
# Description:
# Support function to merge two dictionaries.
#
def merge_dicts(*dict_args):
result = {}
for dictionary in dict_args:
result.update(dictionary)
return result
#######################################
# Start to simulate
cycle = 0
state = initial_state
print('\n---Start simulation---')
print("At the beginning of the simulation the status is: ")
print("Variables:")
print(" var_A =", variables)
print("Initial State:", "INITIALIZE")
print("\n----------------------------------------------------")
#execute_instruction(instruction[state])
repeat = True
while cycle < int(sys.argv[1]) and repeat:
try:
if (not (fsmd_stim['fsmdstimulus']['setinput'] is None)):
for setinput in fsmd_stim['fsmdstimulus']['setinput']:
if type(setinput) is str:
# Only one element
if int(fsmd_stim['fsmdstimulus']['setinput']['cycle']) == cycle:
execute_setinput(fsmd_stim['fsmdstimulus']['setinput']['expression'])
break
else:
# More than 1 element
if int(setinput['cycle']) == cycle:
execute_setinput(setinput['expression'])
except:
pass
print("Cycle " + str(cycle))
print("Current state: " + str(state))
for transition in fsmd[state]:
if evaluate_condition(transition["condition"]):
print("Executing instruction: " + str(transition["instruction"]))
execute_instruction(transition["instruction"])
print("Next state: " + transition["nextstate"])
state = transition["nextstate"]
print("The condition (" + transition["condition"] + ") is True")
print("At the end of cycle " + str(cycle) + ", the status is:")
print(" ", variables)
break
cycle = cycle + 1
try:
if (not (fsmd_stim['fsmdstimulus']['endstate'] is None)):
if state == fsmd_stim['fsmdstimulus']['endstate']:
print('End-state reached.')
repeat = False
sys.exit('End-state reached.')
except:
pass
print("----------------------------------------------------")
print('\n---End of simulation---')
