def visit_printf(self, node, args):
'''
printf function call
'''
# Extract format and args
if len(args) == 0:
self.addwarn("'printf' with zero args at line %s" % (
node.coord.line,))
fmt = Const('?', line=node.coord.line)
else:
if isinstance(args[0], Const):
fmt = args[0]
args = args[1:]
else:
self.addwarn("First argument of 'printf' at lines %s should \
be a format" % (node.coord.line,))
fmt = Const('?', line=node.coord.line)
fmt.value = fmt.value.replace('%lf', '%f')
fmt.value = fmt.value.replace('%ld', '%d')
fmt.value = fmt.value.replace('%lld', '%d')
expr = Op('StrAppend', Var(VAR_OUT),
Op('StrFormat', fmt, *args, line=node.coord.line),
line=node.coord.line)
self.addexpr(VAR_OUT, expr)
def visit_AugAssign(self, node):
# Aug assign to a name
if isinstance(node.target, ast.Name):
target = Var(node.target.id)
self.addtype(node.target.id, '*')
value = self.visit_expr(node.value)
rhs = Op(node.op.__class__.__name__,
target,
value,
line=node.lineno)
self.addexpr(target.name, rhs)
# Aug assign to a index
elif isinstance(node.target, ast.Subscript):
if isinstance(node.target.slice, ast.Index):
var = Var(node.target.value.id)
right = self.visit_expr(node.value)
index = self.visit_expr(node.target.slice.value)
rhs = Op(node.op.__class__.__name__,
self.visit(node.target),
right,
line=node.lineno)
self.addexpr(
var.name,
Op('AssignElement', var, index, rhs, line=node.lineno))
else:
raise NotSupported(
'Subscript assignments only allowed to Indices',
line=node.lineno)
else:
raise NotSupported('Assignments to {} not supported'.format(
node.target.__class__.__name__),
line=node.lineno)
def visit_FuncCall(self, node):
'''
FuncCall
Attrs: name, args
'''
# Get (and check) name
name = self.visit_expr(node.name)
if not isinstance(name, Var):
raise NotSupported("Non-var function name: '%s'" % (name,),
line=name.line)
# Parse args
args = self.visit(node.args) or []
# Special cases (scanf & printf)
if name.name == 'scanf':
return self.visit_scanf(node, args)
elif name.name == 'printf':
return self.visit_printf(node, args)
# Program functions
elif name.name in self.fncs:
return Op('FuncCall', name, *args, line=node.coord.line)
# Library functions
elif name.name in self.LIB_FNCS:
return Op(name.name, *args, line=node.coord.line)
else:
raise NotSupported(
"Unsupported function call: '%s'" % (name.name,),
line=node.coord.line)
def getretcond(self, expr):
if isinstance(expr, Op) and expr.name == 'ite':
icond = expr.args[0]
ct = self.getretcond(expr.args[1])
cf = self.getretcond(expr.args[2])
cond = []
if ct is None and cf is None:
return None
if ct is True and cf is True:
return True
if ct:
if ct is True:
cond.append(icond.copy())
else:
cond.append(Op(self.ANDOP, icond.copy(), ct.copy()))
if cf:
nicond = Op(self.NOTOP, icond)
if cf is True:
cond.append(nicond.copy())
else:
cond.append(Op(self.ANDOP, nicond.copy(), cf.copy()))
if len(cond) == 1:
return cond[0]
else:
return Op(self.OROP, cond[0], cond[1])
elif isinstance(expr, Var) and expr.name == VAR_RET:
return None
else:
return True
def visit_UnaryOp(self, node):
'''
UnaryOp - unary operation
Attrs: op, expr
'''
expr = self.visit_expr(node.expr)
# Special cases
# ++/--
if node.op in ['++', '--']:
if not isinstance(expr, Var):
raise NotSupported('++/-- supported only for Vars',
line=node.coord.line)
self.addexpr(expr.name,
Op(node.op[1], expr.copy(), Const('1'),
line=node.coord.line))
return expr
elif node.op in ['p++', 'p--']:
if not isinstance(expr, Var):
raise NotSupported('p++/p-- supported only for Vars',
line=node.coord.line)
self.addexpr(expr.name,
Op(node.op[1], expr.copy(), Const('1'),
line=node.coord.line))
self.postincdec += 1
return expr
return Op(node.op, expr, line=node.coord.line)
def rmtmp(self, fnc):
'''
Removes (merges) "tmp" or SSA-generated assignments
'''
for loc in fnc.locs():
m = {}
exprs = []
primed = set([])
lastret = None
# Remember "real" vars and replace temps
for var, expr in fnc.exprs(loc):
expr.prime(primed)
for v, e in m.items():
expr = expr.replace(v, e)
if var.endswith('&'):
m[var] = expr
else:
if var == VAR_RET:
lastret = len(exprs)
exprs.append((var, expr))
primed.add(var)
# "Merge" return stmts
nexprs = []
retexpr = None
retcond = None
for i, (var, expr) in enumerate(exprs):
if var == VAR_RET:
tmpretcond = self.getretcond(expr)
if tmpretcond is True or retcond is None:
retcond = tmpretcond
elif tmpretcond is not None and retcond is not True:
retcond = Op(self.OROP, retcond, tmpretcond)
if retexpr:
retexpr = retexpr.replace(VAR_RET, expr)
else:
retexpr = expr
if i == lastret:
nexprs.append((var, retexpr))
else:
if retcond is True:
continue
elif retcond:
expr = Op('ite', Op(self.NOTOP, retcond), expr,
Var(var))
nexprs.append((var, expr))
fnc.replaceexprs(loc, nexprs)
def visit_BoolOp(self, node):
func = node.op.__class__.__name__
val_model = map(self.visit_expr, node.values)
expr = Op(func, val_model[0], val_model[1], line=val_model[1].line)
for v in val_model[2:]:
expr = Op(func, expr, v, line=v.line)
return expr
def visit_Assign(self, node):
if len(node.targets) != 1:
raise NotSupported('Only single assignments allowed')
target = node.targets[0]
# Assignment to a variable
if isinstance(target, ast.Name):
right = self.visit_expr(node.value)
self.addtype(target.id, '*')
self.addexpr(target.id, right)
# Assignment to indexed element
elif isinstance(target, ast.Subscript):
if isinstance(target.slice, ast.Index):
var = Var(target.value.id)
self.addtype(target.value.id, '*')
right = self.visit_expr(node.value)
index = self.visit_expr(target.slice.value)
self.addexpr(
target.value.id,
Op('AssignElement', var, index, right, line=right.line))
else:
raise NotSupported(
'Subscript assignments only allowed to Indices',
line=node.lineno)
# Assignment to a tuple
elif isinstance(target, ast.Tuple):
targets = map(self.visit_expr, target.elts)
right = self.visit_expr(node.value)
for i, target in enumerate(targets):
expr = Op('GetElement',
right.copy(),
Const(str(i)),
line=right.line)
if isinstance(target, Var):
self.addexpr(target.name, expr)
else:
raise NotSupported("Tuple non-var assignment",
line=target.line)
else:
raise NotSupported('Assignments to {} not supported'.format(
target.__class__.__name__),
line=node.lineno)
def visit_Assignment(self, node):
'''
Assignment
Attrs: op, lvalue, rvalue
'''
lvalue = self.visit_expr(node.lvalue)
postincdec = self.postincdec
self.postincdec = 0
rvalue = self.visit(node.rvalue)
postincdec, self.postincdec = self.postincdec, postincdec
if not rvalue:
rvalue = Const('?', line=node.coord.line)
# Cases of assignment operator
if node.op == '=':
pass
elif len(node.op) == 2 and node.op[1] == '=':
rvalue = Op(node.op[0], lvalue.copy(), rvalue, line=rvalue.line)
else:
raise NotSupported("Assignment operator: '%s'" % (node.op,),
line=node.coord.line)
# Distinguish lvalue (ID and Array)
if isinstance(lvalue, Var):
lval = lvalue
elif (isinstance(lvalue, Op) and lvalue.name == '[]'and
isinstance(lvalue.args[0], Var)):
rvalue = Op('ArrayAssign', lvalue.args[0].copy(),
lvalue.args[1].copy(), rvalue, line=node.coord.line)
lval = lvalue.args[0]
else:
raise NotSupported("Assignment lvalue '%s'" % (lvalue,),
line=node.coord.line)
# List of expression
if isinstance(rvalue, list):
rvalue = rvalue[-1]
# Special case when previous assignment was p++/p--
# push this assignment before the previous one
self.addexpr(lval.name, rvalue.copy(),
idx=-postincdec if postincdec else None)
return lvalue
def visit_Decl(self, node):
'''
Decl - Declaration
Attrs: name, quals, storage, funcspec, type, init, bitsize
(using only: name, type & init)
'''
(name, type, dim) = self.visit(node.type)
init = self.visit_expr(node.init, allownone=True)
if not self.fncdef:
try:
self.addtype(name, type)
except AssertionError:
self.addwarn("Ignored global definition '%s' on line %s." % (
name, node.coord.line,))
return
if init and dim:
raise NotSupported("Array Init & Create together",
line=node.coord.line)
if init:
self.addexpr(name, init)
if dim:
self.addexpr(name, Op('ArrayCreate', dim, line=dim.line))
return (name, type, dim)
def visit_InitList(self, node):
'''
Array Initialization List
Attrs: exprs
'''
exprs = map(self.visit_expr, node.exprs or [])
return Op('ArrayInit', *exprs, line=node.coord.line)
def visit_Print(self, node):
'''
Only used in Python 2.x, ignores destination and newline
'''
values_model = map(self.visit_expr, node.values)
expr = Op('StrAppend', Var(VAR_OUT), *values_model, line=node.lineno)
self.addexpr(VAR_OUT, expr)
def visit_Cast(self, node):
'''
Expression case
Attrs: to_type, expr
'''
tt = self.visit(node.to_type)
expr = self.visit_expr(node.expr)
return Op('cast', Const(tt), expr, line=node.coord.line)
def visit_BinaryOp(self, node):
'''
BinaryOp - binary operation
Attrs: op, left, right
'''
return Op(node.op, self.visit_expr(node.left),
self.visit_expr(node.right), line=node.coord.line)
def visit_Expr(self, node):
'''
Expressions need to be handled depending on their type.
Method calls like str.lower() can be ignored
(Strings are immutable), while
calls like list.append() must be handled.
'''
if isinstance(node.value, ast.Call):
if isinstance(node.value.func, ast.Name):
self.warns.append('Ignored call to {} at line {}'.format(
node.value.func.id, node.lineno))
elif isinstance(node.value.func, ast.Attribute):
if node.value.func.attr in self.ATTR_FNCS:
call = self.visit_expr(node.value)
if isinstance(node.value.func.value, ast.Subscript):
var = self.visit_expr(node.value.func.value.value)
index = self.visit_expr(node.value.func.value.slice)
expr = Op('AssignElement',
var,
index,
call,
line=node.lineno)
if isinstance(var, Var):
self.addexpr(var.name, expr)
else:
raise NotSupported("Non-name element assignment",
line=node.lineno)
elif isinstance(node.value.func.value, ast.Name):
var = self.visit(node.value.func.value)
if isinstance(var, Var):
# Skip assignment of 'pop' function
if node.value.func.attr != 'pop':
self.addexpr(var.name, call)
else:
raise NotSupported("Non-name call",
line=node.lineno)
else:
raise NotSupported('Call to {}'.format(
node.value.func.__class__.__name__),
line=node.lineno)
else:
self.warns.append('Ignored call to {} at line {}'.format(
node.value.func.attr, node.lineno))
else:
raise NotSupported('Call to {}'.format(
node.value.func.__class__.__name__),
line=node.lineno)
elif isinstance(node.value,
(ast.Num, ast.Str, ast.List, ast.Tuple, ast.Dict)):
# Happily ignore these side-effect free statements
pass
else:
self.warns.append('Ignored Expr of type {} at line {}'.format(
node.value.__class__.__name__, node.lineno))
def getretcond(self, expr):
if isinstance(expr, Op) and expr.name == 'ite':
icond = expr.args[0]
ct = self.getretcond(expr.args[1])
cf = self.getretcond(expr.args[2])
cond = []
if ct is None and cf is None:
return None
if ct is True and cf is True:
return True
if ct:
if ct is True:
cond.append(icond.copy())
else:
cond.append(Op(self.ANDOP, icond.copy(), ct.copy()))
if cf:
nicond = Op(self.NOTOP, icond)
if cf is True:
cond.append(nicond.copy())
else:
cond.append(Op(self.ANDOP, nicond.copy(), cf.copy()))
if len(cond) == 1:
return cond[0]
else:
return Op(self.OROP, cond[0], cond[1])
elif isinstance(expr, Var) and expr.name == VAR_RET:
return None
else:
return True
def expr_list_and(self, exprs):
if len(exprs) == 0:
return None
else:
newexpr = exprs[0]
for expr in exprs[1:]:
newexpr = Op('&&', newexpr, expr, line=expr.line)
return newexpr
def visit_SetComp(self, node):
elt = self.visit_expr(node.elt)
if len(node.generators) != 1:
raise NotSupported("Only one generator supported",
line=node.lineno)
gen = self.visit_expr(node.generators[0])
return Op('SetComp', elt, gen, line=node.lineno)
def visit_Compare(self, node):
comps_model = map(self.visit, node.comparators)
ops_model = map(lambda x: x.__class__.__name__, node.ops)
left = self.visit_expr(node.left)
right = comps_model[0]
op = ops_model[0]
expr = Op(op, left, right, line=right.line)
left = right
for op, right in zip(ops_model[1:], comps_model[1:]):
expr = Op('And',
expr,
Op(op, left, right, line=right.line),
line=right.line)
left = right
return expr
def visit_DictComp(self, node):
key = self.visit_expr(node.key)
value = self.visit_expr(node.value)
if len(node.generators) != 1:
raise NotSupported("Only one generator supported",
line=node.lineno)
gen = self.visit_expr(node.generators[0])
return Op('DictComp', key, value, gen, line=node.lineno)
def visit_ArrayRef(self, node):
'''
Array reference
Attrs: name, subscript
'''
name = self.visit_expr(node.name)
if not isinstance(name, Var):
raise NotSupported("ArrayName: '%s'" % (name,))
sub = self.visit_expr(node.subscript)
return Op('[]', name, sub, line=node.coord.line)
def visit_Slice(self, node):
args = []
if node.lower is None:
args.append(Const('None'))
else:
args.append(self.visit_expr(node.lower))
if node.upper is None:
args.append(Const('None'))
else:
args.append(self.visit_expr(node.upper))
if node.step is None:
args.append(Const('None'))
else:
args.append(self.visit_expr(node.step))
return Op('Slice', *args)
def visit_comprehension(self, node):
if node.ifs is None or len(node.ifs) == 0:
ifs = Const('True')
elif len(node.ifs) == 1:
ifs = self.visit_expr(node.ifs[0])
else:
raise NotSupported("Comprehension multiple ifs")
target = self.visit(node.target)
if not self.islistofnames(target):
raise NotSupported("Target is not a list of names")
iter = self.visit(node.iter)
return Op('Comp', target, iter, ifs)
def optimizeif(self, preloc, condexpr, trueloc, falseloc):
'''
Optimized "simple" or "loop-less" if statement
'''
# Remove unneded part of the graph
self.fnc.rmtrans(preloc, True)
self.loc = preloc
# Keep track of assigned vars
varss = set()
varsl = []
mt = {}
mf = {}
# Add exprs from branches
def addvars(loc, m):
for (var, expr) in self.fnc.exprs(loc):
newvar = self.ssavar(var)
if var not in varss:
varss.add(var)
varsl.append(var)
# Replace vars mapped so far
for (v1, v2) in m.items():
expr = expr.replace(v1, Var(v2))
expr.original = (var, self.cnt)
self.addexpr(newvar, expr)
# Remember replacement
m[var] = newvar
addvars(trueloc, mt)
if falseloc is not None:
addvars(falseloc, mf)
# Add condition
condvar = self.ssavar('$cond')
self.addexpr(condvar, condexpr.copy())
# Merge branches
for var in varsl:
self.addexpr(
var,
Op('ite', Var(condvar), Var(mt.get(var, var)),
Var(mf.get(var, var))))
def visit_TernaryOp(self, node):
'''
Ternary Operator node
Attrs: cond, iftrue, iffalse
'''
cond = self.visit_expr(node.cond)
n = self.numexprs()
ift = self.visit_expr(node.iftrue)
iff = self.visit_expr(node.iffalse)
if self.numexprs() > n:
self.rmlastexprs(num=self.numexprs() - n)
return self.visit_if(node, node.cond, node.iftrue, node.iffalse)
return Op('ite', cond, ift, iff, line=node.coord.line)
def visit_Call(self, node):
if len(node.keywords) > 0 or node.starargs or node.kwargs:
raise NotSupported(
'starargs, kwargs and keyword arguments not supported',
line=node.lineno)
if isinstance(node.func, ast.Name):
if node.func.id in self.BUILTIN_FNCS:
fncname = node.func.id
args = list(map(self.visit_expr, node.args))
return Op(fncname, *args, line=node.lineno)
else:
fnc = Var(node.func.id)
args = list(map(self.visit_expr, node.args))
return Op('FuncCall', fnc, *args, line=node.lineno)
elif isinstance(node.func, ast.Num):
num = self.visit_expr(node.func)
self.addwarn("Call to a number '%s' on line %s ignored", num,
num.line)
return Const('?')
elif isinstance(node.func, ast.Attribute):
attr = node.func.attr
val = self.visit_expr(node.func.value)
args = list(map(self.visit_expr, node.args))
if isinstance(val, Var) and val.name in self.MODULE_NAMES:
return Op('%s_%s' % (val, attr), *args, line=node.lineno)
if attr == 'pop':
if isinstance(val, Var):
popvar = self.ssavar('pop#')
self.addexpr(popvar, Op(attr, val, *args,
line=node.lineno))
self.addexpr(val.name,
Op('GetElement', Var(popvar), Const('0')))
return Op('GetElement', Var(popvar), Const('1'))
else:
raise NotSupported('Pop to a non-name list')
return Op(attr, val, *args, line=node.lineno)
else:
raise NotSupported('Call of {} not supported'.format(
node.func.__class__.__name__),
line=node.lineno)
def visit_Delete(self, node):
if len(node.targets) > 1:
raise NotSupported('Multiple delete targets')
target = self.visit(node.targets[0])
if isinstance(target, Op):
if target.name == 'GetElement':
if isinstance(target.args[0], Var):
if len(target.args) != 2:
raise NotSupported('Delete target with %d args' %
(len(target.args, )))
delexpr = Op('Delete', *target.args, line=node.lineno)
self.addexpr(target.args[0].name, delexpr)
else:
raise NotSupported('Delete target not Var, but %s' %
(target.args[0].__class__))
else:
raise NotSupported('Delete target op: %s' % (target.name, ))
else:
raise NotSupported('Delete target: %s' % (target.__class__, ))
def visit_For(self, node):
if node.orelse:
raise NotSupported("For-Else not supported",
line=self.getline(node.orelse))
# Iterated expression
it = self.visit_expr(node.iter)
# Targets of iteration
if isinstance(node.target, ast.Name):
targets = [self.visit_expr(node.target)]
elif isinstance(node.target, ast.Tuple):
targets = map(self.visit_expr, node.target.elts)
else:
raise NotSupported('For loop with {} as target'.format(
node.target.__class__.__name__),
line=node.lineno)
hiddenvar = self.hiddenvarcnt
self.hiddenvarcnt += 1
# Set up the iterated variable
iter_name = 'iter#{}'.format(hiddenvar)
it_var = Var(iter_name)
self.addtype(iter_name, '*')
# Set up the iteration index
ind_name = 'ind#{}'.format(hiddenvar)
ind_var = Var(ind_name)
self.addtype(ind_name, 'int')
# Add assignments to iterators
self.addexpr(it_var.name, it)
self.addexpr(ind_var.name, Const(str(0), line=node.lineno))
# Condition is ind_var < len(iter_var)
cond = Op('Lt',
ind_var.copy(),
Op('len', it_var.copy()),
line=node.iter.lineno)
# Assignments to iterated variable(s)
prebody = []
el = Op('GetElement',
it_var.copy(),
ind_var.copy(),
line=node.target.lineno)
if len(targets) == 1:
prebody.append((targets[0].name, el.copy()))
else:
for i, t in enumerate(targets):
eli = Op('GetElement',
el.copy(),
Const(str(i)),
line=node.target.lineno)
prebody.append((t.name, eli))
# Add index variable increment
prebody.append((ind_var.name,
Op('Add',
ind_var.copy(),
Const(str(1)),
line=node.iter.lineno)))
self.visit_loop(node,
None,
cond,
None,
node.body,
False,
'for',
prebody=prebody)
def visit_Subscript(self, node):
val = self.visit_expr(node.value)
return Op('GetElement',
val,
self.visit_expr(node.slice),
line=node.lineno)
def visit_Set(self, node):
elts = map(self.visit_expr, node.elts)
return Op('SetInit', *elts, line=node.lineno)
def visit_Dict(self, node):
keys = map(self.visit_expr, node.keys)
vals = map(self.visit_expr, node.values)
args = list(chain(*zip(keys, vals)))
return Op('DictInit', *args, line=node.lineno)
def visit_For(self, node):
if node.orelse:
raise NotSupported("For-Else not supported",
line=self.getline(node.orelse))
# Iterated expression
it = self.visit_expr(node.iter)
# Targets of iteration
if isinstance(node.target, ast.Name):
self.addtype(node.target.id, '*')
targets = [self.visit_expr(node.target)]
elif isinstance(node.target, ast.Tuple):
for el in node.target.elts:
if isinstance(el, ast.Name):
self.addtype(el.id, '*')
targets = map(self.visit_expr, node.target.elts)
else:
raise NotSupported(
'For loop with {} as target'.format(
node.target.__class__.__name__),
line=node.lineno)
hiddenvar = self.hiddenvarcnt
self.hiddenvarcnt += 1
# Set up the iterated variable
iter_name = 'iter#{}'.format(hiddenvar)
it_var = Var(iter_name)
self.addtype(iter_name, '*')
# Set up the iteration index
ind_name = 'ind#{}'.format(hiddenvar)
ind_var = Var(ind_name)
self.addtype(ind_name, 'int')
# Add assignments to iterators
self.addexpr(it_var.name, it)
self.addexpr(ind_var.name, Const(str(0), line=node.lineno))
# Condition is ind_var < len(iter_var)
cond = Op('Lt', ind_var.copy(), Op('len', it_var.copy()),
line=node.iter.lineno)
# Assignments to iterated variable(s)
prebody = []
el = Op('GetElement', it_var.copy(), ind_var.copy(),
line=node.target.lineno)
if len(targets) == 1:
prebody.append((targets[0].name, el.copy()))
else:
for i, t in enumerate(targets):
eli = Op('GetElement', el.copy(), Const(str(i)),
line=node.target.lineno)
prebody.append((t.name, eli))
# Add index variable increment
prebody.append((ind_var.name,
Op('Add', ind_var.copy(), Const(str(1)),
line=node.iter.lineno)))
self.visit_loop(node, None, cond, None, node.body, False, 'for',
prebody=prebody)
