def update_lvalue(new_ir, node, local_variables_instances,
all_local_variables_instances, state_variables_instances,
all_state_variables_instances):
if isinstance(new_ir, OperationWithLValue):
lvalue = new_ir.lvalue
update_through_ref = False
if isinstance(new_ir, (Assignment, Binary)):
if isinstance(lvalue, ReferenceVariable):
update_through_ref = True
while isinstance(lvalue, ReferenceVariable):
lvalue = lvalue.points_to
if isinstance(lvalue, (LocalIRVariable, StateIRVariable)):
if isinstance(lvalue, LocalIRVariable):
new_var = LocalIRVariable(lvalue)
new_var.index = all_local_variables_instances[
lvalue.name].index + 1
all_local_variables_instances[lvalue.name] = new_var
local_variables_instances[lvalue.name] = new_var
else:
new_var = StateIRVariable(lvalue)
new_var.index = all_state_variables_instances[
lvalue.canonical_name].index + 1
all_state_variables_instances[lvalue.canonical_name] = new_var
state_variables_instances[lvalue.canonical_name] = new_var
if update_through_ref:
phi_operation = Phi(new_var, {node})
phi_operation.rvalues = [lvalue]
node.add_ssa_ir(phi_operation)
if not isinstance(new_ir.lvalue, ReferenceVariable):
new_ir.lvalue = new_var
else:
to_update = new_ir.lvalue
while isinstance(to_update.points_to, ReferenceVariable):
to_update = to_update.points_to
to_update.points_to = new_var
def initiate_all_local_variables_instances(nodes, local_variables_instances, all_local_variables_instances):
for node in nodes:
if node.variable_declaration:
new_var = LocalIRVariable(node.variable_declaration)
if new_var.name in all_local_variables_instances:
new_var.index = all_local_variables_instances[new_var.name].index + 1
local_variables_instances[node.variable_declaration.name] = new_var
all_local_variables_instances[node.variable_declaration.name] = new_var
def get(variable):
if isinstance(variable, LocalVariable):
if variable.name in local_variables_instances:
return local_variables_instances[variable.name]
new_var = LocalIRVariable(variable)
local_variables_instances[variable.name] = new_var
all_local_variables_instances[variable.name] = new_var
return new_var
if isinstance(
variable, StateVariable
) and variable.canonical_name in state_variables_instances:
return state_variables_instances[variable.canonical_name]
elif isinstance(variable, ReferenceVariable):
if not variable.index in reference_variables_instances:
new_variable = ReferenceVariable(variable.node,
index=variable.index)
if variable.points_to:
new_variable.points_to = get(variable.points_to)
new_variable.set_type(variable.type)
reference_variables_instances[variable.index] = new_variable
return reference_variables_instances[variable.index]
elif isinstance(variable, TemporaryVariable):
if not variable.index in temporary_variables_instances:
new_variable = TemporaryVariable(variable.node,
index=variable.index)
new_variable.set_type(variable.type)
temporary_variables_instances[variable.index] = new_variable
return temporary_variables_instances[variable.index]
return variable
def get(variable, local_variables_instances, state_variables_instances, temporary_variables_instances, reference_variables_instances, tuple_variables_instances, all_local_variables_instances):
# variable can be None
# for example, on LowLevelCall, ir.lvalue can be none
if variable is None:
return None
if isinstance(variable, LocalVariable):
if variable.name in local_variables_instances:
return local_variables_instances[variable.name]
new_var = LocalIRVariable(variable)
local_variables_instances[variable.name] = new_var
all_local_variables_instances[variable.name] = new_var
return new_var
if isinstance(variable, StateVariable) and variable.canonical_name in state_variables_instances:
return state_variables_instances[variable.canonical_name]
elif isinstance(variable, ReferenceVariable):
if not variable.index in reference_variables_instances:
new_variable = ReferenceVariableSSA(variable)
if variable.points_to:
new_variable.points_to = get(variable.points_to,
local_variables_instances,
state_variables_instances,
temporary_variables_instances,
reference_variables_instances,
tuple_variables_instances,
all_local_variables_instances)
new_variable.set_type(variable.type)
reference_variables_instances[variable.index] = new_variable
return reference_variables_instances[variable.index]
elif isinstance(variable, TemporaryVariable):
if not variable.index in temporary_variables_instances:
new_variable = TemporaryVariableSSA(variable)
new_variable.set_type(variable.type)
temporary_variables_instances[variable.index] = new_variable
return temporary_variables_instances[variable.index]
elif isinstance(variable, TupleVariable):
if not variable.index in tuple_variables_instances:
new_variable = TupleVariableSSA(variable)
new_variable.set_type(variable.type)
tuple_variables_instances[variable.index] = new_variable
return tuple_variables_instances[variable.index]
assert isinstance(variable, (Constant,
SolidityVariable,
Contract,
Enum,
SolidityFunction,
Structure,
Function,
Type)) # type for abi.decode(.., t)
return variable
def last_name(n, var, init_vars):
candidates = []
# Todo optimize by creating a variables_ssa_written attribute
for ir_ssa in n.irs_ssa:
if isinstance(ir_ssa, OperationWithLValue):
lvalue = ir_ssa.lvalue
while isinstance(lvalue, ReferenceVariable):
lvalue = lvalue.points_to
if lvalue and lvalue.name == var.name:
candidates.append(lvalue)
if n.variable_declaration and n.variable_declaration.name == var.name:
candidates.append(LocalIRVariable(n.variable_declaration))
if n.type == NodeType.ENTRYPOINT:
if var.name in init_vars:
candidates.append(init_vars[var.name])
assert candidates
return max(candidates, key=lambda v: v.index)
def add_ssa_ir(function, all_state_variables_instances):
'''
Add SSA version of the IR
Args:
function
all_state_variables_instances
'''
if not function.is_implemented:
return
init_definition = dict()
for v in function.parameters + function.returns:
if v.name:
init_definition[v.name] = (v, function.entry_point)
# We only add phi function for state variable at entry node if
# The state variable is used
# And if the state variables is written in another function (otherwise its stay at index 0)
for (_, variable_instance) in all_state_variables_instances.items():
if is_used_later(function.entry_point, variable_instance):
# rvalues are fixed in solc_parsing.declaration.function
function.entry_point.add_ssa_ir(
Phi(StateIRVariable(variable_instance), set()))
add_phi_origins(function.entry_point, init_definition, dict())
for node in function.nodes:
for (variable, nodes) in node.phi_origins_local_variables.values():
if len(nodes) < 2:
continue
if not is_used_later(node, variable):
continue
node.add_ssa_ir(Phi(LocalIRVariable(variable), nodes))
for (variable, nodes) in node.phi_origins_state_variables.values():
if len(nodes) < 2:
continue
#if not is_used_later(node, variable.name, []):
# continue
node.add_ssa_ir(Phi(StateIRVariable(variable), nodes))
init_local_variables_instances = dict()
for v in function.parameters:
if v.name:
new_var = LocalIRVariable(v)
function.add_parameter_ssa(new_var)
if new_var.is_storage:
fake_variable = LocalIRVariable(v)
fake_variable.name = 'STORAGE_' + fake_variable.name
fake_variable.set_location('reference_to_storage')
new_var.refers_to = {fake_variable}
init_local_variables_instances[
fake_variable.name] = fake_variable
init_local_variables_instances[v.name] = new_var
for v in function.returns:
if v.name:
new_var = LocalIRVariable(v)
function.add_return_ssa(new_var)
if new_var.is_storage:
fake_variable = LocalIRVariable(v)
fake_variable.name = 'STORAGE_' + fake_variable.name
fake_variable.set_location('reference_to_storage')
new_var.refers_to = {fake_variable}
init_local_variables_instances[
fake_variable.name] = fake_variable
init_local_variables_instances[v.name] = new_var
all_init_local_variables_instances = dict(init_local_variables_instances)
init_state_variables_instances = dict(all_state_variables_instances)
initiate_all_local_variables_instances(function.nodes,
init_local_variables_instances,
all_init_local_variables_instances)
generate_ssa_irs(function.entry_point,
dict(init_local_variables_instances),
all_init_local_variables_instances,
dict(init_state_variables_instances),
all_state_variables_instances,
init_local_variables_instances, [])
fix_phi_rvalues_and_storage_ref(function.entry_point,
dict(init_local_variables_instances),
all_init_local_variables_instances,
dict(init_state_variables_instances),
all_state_variables_instances,
init_local_variables_instances)