def get_synthesizer():
code = """a = HOLE"""
vars = contract.ProgramVars({'x': 'Int', 'y': 'Int'}, {'a': 'Int'})
code_pre = 'x >= 1 and y >= 1'
code_post = 'a == 6*x + y'
sygus_grammar = """
(
( Start Int
( ( Constant Int ) x y (+ Start Start) (* ( Constant Int ) Start) )
)
)
""" #(- Start Start)
grammar = templates.load_gramar_from_SYGUS_spec(sygus_grammar)
hole = smt_synthesis.HoleDecl('HOLE',
grammar, {
'x': 'Int',
'y': 'Int'
},
is_expression_hole=True,
max_depth=3)
env = utils.Options({
'--solver': 'z3',
'--logic': 'NIA',
'--produce_proofs': True,
'--silent': True
})
return smt_synthesis.SynthesizerSMT(code, code_pre, code_post, vars, env,
[hole])
def test_program_already_in_ssa_form(self):
code = 'x = 0; y = 1; z = 2'
post = 'z < 2'
vars = contract.ProgramVars({'x': 'Int', 'y': 'Int'}, {'z': 'Int'})
# Running SSA conversion
ib = ast_utils.py_to_interm_ib(code)
post = ast_utils.py_to_interm_expr(post)
ib2, post2 = ssa_converter.convert(ib, post, vars)
vars.add_marked_variables(ib2.src.collect_variables())
# Assertions
self.assertFalse(ib.src.equals(ib2.src))
# -----------------------------------
self.assertEquals("|x'|", ib2.src.instructions[0].var.id)
self.assertEquals("|y'|", ib2.src.instructions[1].var.id)
self.assertEquals("z", ib2.src.instructions[2].var.id)
self.assertEquals(3, ib2.src.size())
self.assertEquals("z", post2.src.expr.args[0].id)
ib2, post2 = ssa_converter.convert(ib2, post2, vars)
self.assertFalse(ib.src.equals(ib2))
# -----------------------------------
self.assertEquals("|x'|", ib2.src.instructions[0].var.id)
self.assertEquals("|y'|", ib2.src.instructions[1].var.id)
self.assertEquals("z", ib2.src.instructions[2].var.id)
self.assertEquals(3, ib2.src.size())
self.assertEquals("z", post2.src.expr.args[0].id)
def test_4():
code = """
res = x
if x < 0:
HOLE
return res
"""
input_vars = contract.ProgramVars({'x': 'Int', 'res': 'Double'})
pre = 'True'
post = 'res >= 0'
pysv.smt_synthesis.synthesize(code, pre, post, input_vars)
def test_ssa_form_holes(self):
code = """
trigger = False
newAcc = acc + 2
newAcc = newAcc - 1
if newAcc < limit:
trigger = False
else:
newAcc = HOLE # should be 0
newAcc = newAcc - 1
trigger = True
"""
post = 'True'
vars = contract.ProgramVars({
'acc': 'Int',
'limit': 'Int'
}, {
'newAcc': 'Int',
'trigger': 'Bool'
})
grammar_spec = """
(
( Start Int
( ( Constant Int ) acc limit newAcc)
)
)
"""
from pysv import templates
grammar = templates.load_gramar_from_SYGUS_spec(grammar_spec)
hole = smt_synthesis.HoleDecl('HOLE', grammar, None, True)
ib = ast_utils.py_to_interm_ib(code, [hole])
holes = ib.src.get_holes_definitions()
self.assertEquals(1, len(holes))
self.assertEquals({
'acc': 'Int',
'limit': 'Int',
'newAcc': 'Int'
}, holes[0].vars)
post = ast_utils.py_to_interm_expr(post)
ib2, post2 = ssa_converter.convert(ib, post, vars)
holes = ib2.src.get_holes_definitions()
self.assertEquals(1, len(holes))
self.assertEquals({
'acc': 'Int',
'limit': 'Int',
"|newAcc'|": 'Int'
}, holes[0].vars)
def test_verify_smt2_simple_program(self):
prog = "(= res (ite (= x 5) -1 1))"
pre = "true"
post = "(> res 0)"
program_vars = contract.ProgramVars({'x': 'Int'}, {'res': 'Int'})
env = utils.Options(["--lang", "smt2"])
res = smt_verifier.verify(prog, pre, post, program_vars, env)
self.assertEquals('sat', res.decision)
self.assertEquals('5', res.model['x'])
self.assertEquals({'x': '5'}, res.witness)
post = "(>= res -1)"
res = smt_verifier.verify(prog, pre, post, program_vars, env)
self.assertEquals('unsat', res.decision)
self.assertEquals({}, res.model)
self.assertEquals({}, res.witness)
def test_verify_smt2_minimize(self):
prog = "true"
pre = "true"
post = "(and (< res 0) (<= res 0) (= res 0) (= res 0))"
program_vars = contract.ProgramVars({'res': 'Int'}, {})
env = utils.Options([
"--lang", "smt2", "--ver_mode", "min", "--post_in_cnf", 1,
"--ver_annotate_post", 1, "--logic", "LIA",
"--produce_assignments", 1
])
res = smt_verifier.verify(prog, pre, post, program_vars, env)
self.assertEquals('sat', res.decision)
self.assertEquals(True, int(res.model['res']) > 0)
self.assertEquals('false', res.assignments['post_0'])
self.assertEquals('false', res.assignments['post_1'])
self.assertEquals('false', res.assignments['post_2'])
self.assertEquals('false', res.assignments['post_3'])
def test_6():
"""Testing the synthesis of a Python program."""
code = """
trigger = False
newAcc = acc + 1
if newAcc < limit:
trigger = False
else:
newAcc = HOLE # should be 0
newAcc = newAcc - 1
trigger = True
"""
vars = contract.ProgramVars({
'acc': 'Int',
'limit': 'Int'
}, {
'newAcc': 'Int',
'trigger': 'Bool'
})
code_pre = 'acc < limit and acc >= 0 and limit > 0'
t1 = (['acc == limit - 1'], ['trigger == True', 'newAcc == 0'])
t2 = (['acc < limit - 1'], ['trigger == False', 'newAcc == acc + 1'])
code_post = contract.formula_test_cases_py([t1, t2])
grammar_spec = """
(
( Start Int
( ( Constant Int ) acc limit newAcc)
)
)
"""
import pysv.templates
grammar = pysv.templates.load_gramar_from_SYGUS_spec(grammar_spec)
hole = pysv.smt_synthesis.HoleDecl('HOLE', grammar, vars.input_vars, True)
holes_defs = {hole.id: hole}
res = pysv.smt_synthesis.synthesize(code, code_pre, code_post, vars,
holes_defs)
# Printing result
print('******** Z3 RESULT ********\n' + str(res))
if res.decision == 'sat':
print("MODEL FOUND!")
elif res.decision == 'unsat':
print("MODEL NOT FOUND!")
def test_simple_program_no_ifs(self):
code = 'x=0; y=1; z=2; x=3; y=4'
post = 'x<2 and z<2'
vars = contract.ProgramVars({'x': 'Int', 'y': 'Int', 'z': 'Int'})
# Running SSA conversion
ib = ast_utils.py_to_interm_ib(code)
post = ast_utils.py_to_interm_expr(post)
ib2, post2 = ssa_converter.convert(ib, post, vars)
# Assertions
self.assertEquals("|x'|", ib2.src.instructions[0].var.id)
self.assertEquals("|y'|", ib2.src.instructions[1].var.id)
self.assertEquals("|z'|", ib2.src.instructions[2].var.id)
self.assertEquals("|x''|", ib2.src.instructions[3].var.id)
self.assertEquals("|y''|", ib2.src.instructions[4].var.id)
self.assertEquals(5, ib2.src.size())
self.assertEquals("|x''|", post2.src.expr.args[0].args[0].id)
self.assertEquals("|z'|", post2.src.expr.args[1].args[0].id)
def synthesize_max():
code = """
if H1:
res = H2
else:
res = H3
"""
code_pre = 'True'
code_post = 'res >= x and res >= y and (res == x or res == y)'
# Specification of the hole's template in the form of the grammar in SYGUS format.
sygus_grammar_hole1 = """
(
( Start Bool
( (Constant Bool) (> TermInt TermInt) (>= TermInt TermInt) (= TermInt TermInt) (<= TermInt TermInt) (< TermInt TermInt)
)
)
( TermInt Int
( (Constant Int) x y )
)
)
"""
sygus_grammar_hole23 = """
(
( Start Int
( (Constant Int) x y (+ x y) (- x y) (- y x) (+ x ( Constant Int )) (+ y ( Constant Int )) )
)
)
"""
grammar1 = templates.load_gramar_from_SYGUS_spec(sygus_grammar_hole1)
grammar23 = templates.load_gramar_from_SYGUS_spec(sygus_grammar_hole23)
pv = contract.ProgramVars({'x': 'Int', 'y': 'Int'}, {'res': 'Int'})
h1 = smt_synthesis.HoleDecl('H1', grammar1, pv, True, 2)
h2 = smt_synthesis.HoleDecl('H2', grammar23, pv, True, 2)
h3 = smt_synthesis.HoleDecl('H3', grammar23, pv, True, 2)
hole_decls = [h1, h2, h3]
# The result is currently only a raw output from the solver, but one can verify from the model
# that synthesized program is correct.
env = utils.Options(['--solver', 'z3', '--logic', 'NIA'])
res = smt_synthesis.synthesize(code, code_pre, code_post, pv, env,
hole_decls)
return res
def test_7():
"""Testing the synthesis of a Python program."""
code = """
a = HOLE
if x != 5:
a = a + 1
else:
a = a - 1
"""
vars = contract.ProgramVars({'x': 'Int', 'y': 'Int'}, {'a': 'Int'})
code_pre = 'x >= 1 and y >= 1'
code_post = 'a == 6*x + y'
grammar_spec = """
(
( Start Int
( ( Constant Int ) x y (+ Start Start) (* ( Constant Int ) Start) )
)
)
"""
import pysv.templates
grammar = pysv.templates.load_gramar_from_SYGUS_spec(grammar_spec)
hole = pysv.smt_synthesis.HoleDecl('HOLE',
grammar, {
'x': 'Int',
'y': 'Int'
},
True,
max_depth=3)
holes_defs = {hole.id: hole}
res = pysv.smt_synthesis.synthesize(code, code_pre, code_post, vars,
holes_defs)
# Printing result
print('******** Z3 RESULT ********')
print(res.text)
print('--------------------------\n')
print('SYNTHESIZED PYTHON CODE:')
print(res.final_code)
def synthesize_keijzer12():
smtgp_nia_grammar = """
(
( Start Int
( x y (Constant Int) (+ Start Start) (- Start Start) (* Start Start) (div Start Start) (ite SBool Start Start) )
)
( SBool Bool
( (> Start Start) (>= Start Start) (< Start Start) (<= Start Start) (= Start Start) (= SBool SBool) )
)
)
"""
vars = contract.ProgramVars({'x': 'Int', 'y': 'Int'}, {'res': 'Int'})
code = """(= res H1)"""
code_pre = 'true'
code_post = 'true'
grammar = templates.load_gramar_from_SYGUS_spec(smtgp_nia_grammar)
h1 = smt_synthesis.HoleDecl('H1', grammar, {'x': 'Int', 'y': 'Int'}, True, 6)
hole_decls = [h1]
tc = contract.TestCases.from_csv(csv_keijzer12)
env = utils.Options(['--solver', 'z3', '--logic', 'NIA', "--lang", "smt2"])
res = smt_synthesis.synthesize_tc(tc, code, code_pre, code_post, vars, env, hole_decls)
return res
def test_5():
"""Testing the generation of SMT-LIB script and solving it with z3.
"""
code = """
z = 6
if (y > 4):
y = x * (x + y)
else:
z = 6
"""
input_vars = contract.ProgramVars({'x': 'Int', 'y': 'Int', 'z': 'Int'})
code_pre = 'x >= 2 and y > 2'
code_post = 'y > x and y < z'
# Converting source code into internal code representation
ib, pre, post = pysv.smt_verifier.process_source_code(
code, code_pre, code_post)
ib, post = pysv.ssa_converter.convert(ib, pre, post, input_vars)
# Specifying variables and their types
input_vars.add_marked_variables(ib.collect_variables())
print('VARIABLES: ' + str(input_vars))
# Producing SMT-LIB script
smtlib = SMTLIBConstraints(show_comments=False)
script = smtlib.produce_script_verification(ib, pre, post, input_vars)
print('\n\n******** SCRIPT ********:\n' + script)
# Solving constraints
solverZ3 = SolverZ3()
res = solverZ3.apply(script)
# Printing result
print('******** Z3 RESULT ********\n' + str(res))
if res.decision == 'sat':
print("MODEL FOUND!")
elif res.decision == 'unsat':
print("MODEL NOT FOUND!")
if res.decision == 'unsat':
print('Counterexample not found! Program is correct.')
elif res.decision == 'sat':
print(res.witness)
print('Counterexample found! Program is incorrect.')
print('----------------------------------------------\n\n')
return res
#------------------------------------------------------------------------
# MAIN
#------------------------------------------------------------------------
precondition = 'True'
postcondition = "res >= x and res >= y and (res == x or res == y)"
variables = contract.ProgramVars({'x': 'Int', 'y': 'Int'}, {'res': 'Int'})
# First, we will verify incorrect implementation of the program. Notice that a counterexample is returned.
code =\
"""
if x < y:
res = x
else:
res = y
"""
verify_code(code, precondition, postcondition, variables)
# After previous verification we analyzed the code and slightly changed condition in the IF statement.
# The code should now be correct, but just to be sure we run verifier yet again.
code =\
"""
# Only one leap
zune_simplified = """
#year = 1980
#if days > 365: # handled by precondition
days2 = days
year2 = year
if year % 4 == 0:
if days > 366:
days2 = days - 366
year2 = year + 1
# lack of else statement
else:
days2 = days - 365
year2 = year + 1
"""
input_vars = contract.ProgramVars({"days": 'Int', "year": 'Int'})
pre = "days > 365 and year >= 1980"
# For this postcondition program doesn't meet the specification because the postcondition
# is based on user intent and cod has a bug.
# post = "((not days == 366 or not year == 1980) or (year2 == 1980 and days2 == 0)) and " +\
# "((not days == 366 or not year == 1981) or (year2 == 1982 and days2 == 1))"
# For this postcondition program meets the specification because the postcondition
# is based on the code.
#post = "((not days == 366 or not year == 1980) or (year2 == 1980 and days2 == 366)) and " +\
# "((not days == 366 or not year == 1981) or (year2 == 1982 and days2 == 1))"
t1 = (["days == 366", "year == 1980"], ["year2 == 1980", "days2 == 366"])
t2 = (["days == 366", "year == 1981"], ["year2 == 1982", "days2 == 1"])
post = contract.formula_test_cases_py([t1, t2])
days = 9
def test_simple_program_one_if(self):
code = """
x = 0
y = 0
if x<2:
x = 1
x = x + 1
else:
x = 3
y = 2
x = x + 5
"""
post = 'x<2 and y<2'
vars = contract.ProgramVars({'x': 'Int'}, {'y': 'Int'})
# Running SSA conversion
ib = ast_utils.py_to_interm_ib(code)
post = ast_utils.py_to_interm_expr(post)
ib2, post2 = ssa_converter.convert(ib, post, vars)
# Assertions
self.assertEquals("|x'|", ib2.src.instructions[0].var.id)
self.assertEquals("y", ib2.src.instructions[1].var.id)
if_instr = ib2.src.instructions[2]
self.assertEquals("<(|x'|, 2)", str(if_instr.condition))
# BODY branch
self.assertEquals("|x''| = 1", str(if_instr.body[0]))
self.assertEquals("|x''|", if_instr.body[0].var.id)
self.assertEquals(False, if_instr.body[0].is_meta)
self.assertEquals("|x'''| = +(|x''|, 1)", str(if_instr.body[1]))
self.assertEquals("|x'''|", if_instr.body[1].var.id)
self.assertEquals(False, if_instr.body[1].is_meta)
# meta
self.assertEquals("|x'''''| = |x'''| (meta)", str(if_instr.body[2]))
self.assertEquals("|x'''''|", if_instr.body[2].var.id)
self.assertEquals("|x'''|", if_instr.body[2].expr.id)
self.assertEquals(True, if_instr.body[2].is_meta)
self.assertEquals("|y''| = y (meta)", str(if_instr.body[3]))
self.assertEquals("|y''|", if_instr.body[3].var.id)
self.assertEquals("y", if_instr.body[3].expr.id)
self.assertEquals(True, if_instr.body[3].is_meta)
# ORELSE branch
self.assertEquals("|x''''| = 3", str(if_instr.orelse[0]))
self.assertEquals("|x''''|", if_instr.orelse[0].var.id)
self.assertEquals(False, if_instr.orelse[0].is_meta)
self.assertEquals("|y'| = 2", str(if_instr.orelse[1]))
self.assertEquals("|y'|", if_instr.orelse[1].var.id)
self.assertEquals(False, if_instr.orelse[1].is_meta)
# meta
self.assertEquals("|x'''''| = |x''''| (meta)",
str(if_instr.orelse[2]))
self.assertEquals("|x'''''|", if_instr.orelse[2].var.id)
self.assertEquals("|x''''|", if_instr.orelse[2].expr.id)
self.assertEquals(True, if_instr.orelse[2].is_meta)
self.assertEquals("|y''| = |y'| (meta)", str(if_instr.orelse[3]))
self.assertEquals("|y''|", if_instr.orelse[3].var.id)
self.assertEquals("|y'|", if_instr.orelse[3].expr.id)
self.assertEquals(True, if_instr.orelse[3].is_meta)
# After if
self.assertEquals("|x''''''|", ib2.src.instructions[3].var.id)
self.assertEquals("|x'''''|", ib2.src.instructions[3].expr.args[0].id)
# Postcondition
self.assertEquals("|x''''''|", post2.src.expr.args[0].args[0].id)
self.assertEquals("|y''|", post2.src.expr.args[1].args[0].id)
def get_program_vars(env):
in_vars = {vt.split(":")[0]: vt.split(":")[1] for vt in env.input_vars}
loc_vars = {vt.split(":")[0]: vt.split(":")[1] for vt in env.local_vars}
return contract.ProgramVars(in_vars, loc_vars)
True,
max_depth=4)
return [h1]
if __name__ == "__main__":
if len(sys.argv) == 1 or "-h" in sys.argv or "--help" in sys.argv:
print("Usage: ./get_final_code.py [raw output from SMT solver]")
exit()
result = sys.argv[1]
# Original source code (fixed for this prettifier instance).
original_code = get_original_code()
# Hole declarations (fixed for this prettifier instance).
holes_decls = get_hole_declarations(
contract.ProgramVars(input_vars={
"x": "Int",
"y": "Int",
"z": "Int"
}))
# Options (fixed for this prettifier instance).
env = utils.Options(merge_with_vargs=False)
res = smt_synthesis.SynthesisResult(result, original_code, holes_decls,
env)
print("FINAL CODE:")
print(res.final_code)
#
# I think that this is a very convenient compromise between full formal contracts and test cases as
# we know from GP.
t1 = (['acc == limit - 1'], ['trigger == True', 'newAcc == 0'])
t2 = (['acc < limit - 1'], ['trigger == False', 'newAcc == acc + 1'])
postcondition = contract.formula_test_cases_py([t1, t2])
# We must also specify types of variables used in the program, because dynamic typing in Python
# does not allow us to reliably obtain this information via reflection. In Scala this could be
# automatically generated from the source code.
variables = contract.ProgramVars({
'acc': 'Int',
'limit': 'Int'
}, {
'newAcc': 'Int',
'trigger': 'Bool'
})
# First, we will verify incorrect implementation of the modulo counter. If user invokes this program
# for example with 'acc' equal to 2 and 'limit' equal to 3, then counter modulo three will return 3,
# which is incorrect.
#
# As can be seen, verifier without any problems discovers an example of incorrect behavior.
code =\
"""
trigger = False
if acc < limit:
newAcc = acc + 1
else: