def assign(self):
# Assignment (e.g. x[4] = y)
if len(self.stmt.targets) != 1:
raise StructureException("Assignment statement must have one target", self.stmt)
self.context.set_in_assignment(True)
sub = Expr(self.stmt.value, self.context).lll_node
# Disallow assignment to None
if isinstance(sub.typ, NullType):
raise InvalidLiteralException('Assignment to None is not allowed, use a default value or built-in `clear()`.', self.stmt)
# Determine if it's an RLPList assignment.
if isinstance(self.stmt.value, ast.Call) and getattr(self.stmt.value.func, 'id', '') is 'RLPList':
pos = self.context.new_variable(self.stmt.targets[0].id, sub.typ)
variable_loc = LLLnode.from_list(pos, typ=sub.typ, location='memory', pos=getpos(self.stmt), annotation=self.stmt.targets[0].id)
o = make_setter(variable_loc, sub, 'memory', pos=getpos(self.stmt))
# All other assignments are forbidden.
elif isinstance(self.stmt.targets[0], ast.Name) and self.stmt.targets[0].id not in self.context.vars:
raise VariableDeclarationException("Variable type not defined", self.stmt)
elif isinstance(self.stmt.targets[0], ast.Tuple) and isinstance(self.stmt.value, ast.Tuple):
raise VariableDeclarationException("Tuple to tuple assignment not supported", self.stmt)
else:
# Checks to see if assignment is valid
target = self.get_target(self.stmt.targets[0])
o = make_setter(target, sub, target.location, pos=getpos(self.stmt))
o.pos = getpos(self.stmt)
self.context.set_in_assignment(False)
return o
def assign(self):
# Assignment (e.g. x[4] = y)
if len(self.stmt.targets) != 1:
raise StructureException(
"Assignment statement must have one target", self.stmt)
with self.context.assignment_scope():
sub = Expr(self.stmt.value, self.context).lll_node
# Disallow assignment to None
if isinstance(sub.typ, NullType):
raise InvalidLiteralException(
'Assignment to None is not allowed, use a default value or built-in `clear()`.',
self.stmt)
# Determine if it's an RLPList assignment.
if isinstance(self.stmt.value, ast.Call) and getattr(
self.stmt.value.func, 'id', '') == 'RLPList':
pos = self.context.new_variable(self.stmt.targets[0].id,
sub.typ)
variable_loc = LLLnode.from_list(
pos,
typ=sub.typ,
location='memory',
pos=getpos(self.stmt),
annotation=self.stmt.targets[0].id)
o = make_setter(variable_loc,
sub,
'memory',
pos=getpos(self.stmt))
else:
# Error check when assigning to declared variable
if isinstance(self.stmt.targets[0], ast.Name):
# Do not allow assignment to undefined variables without annotation
if self.stmt.targets[0].id not in self.context.vars:
raise VariableDeclarationException(
"Variable type not defined", self.stmt)
# Check against implicit conversion
self._check_implicit_conversion(self.stmt.targets[0].id,
sub)
# Do no allow tuple-to-tuple assignment
if isinstance(self.stmt.targets[0], ast.Tuple) and isinstance(
self.stmt.value, ast.Tuple):
raise VariableDeclarationException(
"Tuple to tuple assignment not supported", self.stmt)
# Checks to see if assignment is valid
target = self.get_target(self.stmt.targets[0])
o = make_setter(target,
sub,
target.location,
pos=getpos(self.stmt))
o.pos = getpos(self.stmt)
return o
def assign(self):
# Assignment (e.g. x[4] = y)
with self.context.assignment_scope():
sub = Expr(self.stmt.value, self.context).lll_node
is_valid_rlp_list_assign = (
isinstance(self.stmt.value, vy_ast.Call)
) and getattr(self.stmt.value.func, 'id', '') == 'RLPList'
# Determine if it's an RLPList assignment.
if is_valid_rlp_list_assign:
pos = self.context.new_variable(self.stmt.target.id, sub.typ)
variable_loc = LLLnode.from_list(
pos,
typ=sub.typ,
location='memory',
pos=getpos(self.stmt),
annotation=self.stmt.target.id,
)
o = make_setter(variable_loc, sub, 'memory', pos=getpos(self.stmt))
else:
# Error check when assigning to declared variable
if isinstance(self.stmt.target, vy_ast.Name):
# Do not allow assignment to undefined variables without annotation
if self.stmt.target.id not in self.context.vars:
raise VariableDeclarationException("Variable type not defined", self.stmt)
# Check against implicit conversion
self._check_implicit_conversion(self.stmt.target.id, sub)
is_valid_tuple_assign = (
isinstance(self.stmt.target, vy_ast.Tuple)
) and isinstance(self.stmt.value, vy_ast.Tuple)
# Do no allow tuple-to-tuple assignment
if is_valid_tuple_assign:
raise VariableDeclarationException(
"Tuple to tuple assignment not supported",
self.stmt,
)
# Checks to see if assignment is valid
target = self.get_target(self.stmt.target)
if isinstance(target.typ, ContractType) and not isinstance(sub.typ, ContractType):
raise TypeMismatch(
'Contract assignment expects casted address: '
f'{target.typ}(<address_var>)',
self.stmt
)
o = make_setter(target, sub, target.location, pos=getpos(self.stmt))
o.pos = getpos(self.stmt)
return o
def abi_decode(lll_node, src, pos=None):
os = o_list(lll_node, pos=pos)
lll_ret = ["seq"]
parent_abi_t = abi_type_of(lll_node.typ)
for i, o in enumerate(os):
abi_t = abi_type_of(o.typ)
src_loc = LLLnode("src_loc", typ=o.typ, location=src.location)
if parent_abi_t.is_tuple():
if abi_t.is_dynamic():
child_loc = ["add", "src", unwrap_location(src_loc)]
child_loc = LLLnode.from_list(child_loc,
typ=o.typ,
location=src.location)
else:
child_loc = src_loc
# descend into the child tuple
lll_ret.append(abi_decode(o, child_loc, pos=pos))
else:
lll_ret.append(
make_setter(o, src_loc, location=o.location, pos=pos))
if i + 1 == len(os):
pass # optimize out the last pointer increment
else:
sz = abi_t.embedded_static_size()
lll_ret.append(["set", "src_loc", ["add", "src_loc", sz]])
lll_ret = ["with", "src", src, ["with", "src_loc", "src", lll_ret]]
return lll_ret
def parse_Assign(self):
# Assignment (e.g. x[4] = y)
sub = Expr(self.stmt.value, self.context).lll_node
target = self._get_target(self.stmt.target)
lll_node = make_setter(target, sub, target.location, pos=getpos(self.stmt))
lll_node.pos = getpos(self.stmt)
return lll_node
def parse_AnnAssign(self):
typ = parse_type(
self.stmt.annotation, location="memory", custom_structs=self.context.structs,
)
varname = self.stmt.target.id
pos = self.context.new_variable(varname, typ, pos=self.stmt)
if self.stmt.value is None:
return
sub = Expr(self.stmt.value, self.context).lll_node
is_literal_bytes32_assign = (
isinstance(sub.typ, ByteArrayType)
and sub.typ.maxlen == 32
and isinstance(typ, BaseType)
and typ.typ == "bytes32"
and sub.typ.is_literal
)
# If bytes[32] to bytes32 assignment rewrite sub as bytes32.
if is_literal_bytes32_assign:
sub = LLLnode(
bytes_to_int(self.stmt.value.s), typ=BaseType("bytes32"), pos=getpos(self.stmt),
)
variable_loc = LLLnode.from_list(pos, typ=typ, location="memory", pos=getpos(self.stmt),)
lll_node = make_setter(variable_loc, sub, "memory", pos=getpos(self.stmt))
return lll_node
def abi_decode(lll_node, src, pos=None):
os = o_list(lll_node, pos=pos)
lll_ret = []
src_ptr = 'src' # pointer to beginning of buffer
src_loc = 'src_loc' # pointer to read location in static section
parent_abi_t = abi_type_of(src.typ)
for i, o in enumerate(os):
abi_t = abi_type_of(o.typ)
src_loc = LLLnode('src_loc', typ=o.typ, location=src.location)
if parent_abi_t.is_tuple():
if abi_t.is_dynamic():
child_loc = ['add', src_ptr, unwrap_location(src_loc)]
else:
child_loc = src_loc
# descend into the child tuple
lll_ret.append(abi_decode(o, child_loc, pos=pos))
else:
lll_ret.append(make_setter(o, src_loc))
if i + 1 == len(os):
pass # optimize out the last pointer increment
else:
sz = abi_t.embedded_static_size()
lll_ret.append(['set', src_loc, ['add', src_loc, sz]])
lll_ret = [
'with', 'src', src, ['with', 'src_loc', 'src', ['seq', lll_ret]]
]
return lll_ret
def parse_Tuple(self):
if not len(self.expr.elements):
return
call_lll = []
multi_lll = []
for node in self.expr.elements:
if isinstance(node, vy_ast.Call):
# for calls inside the tuple, we perform the call prior to building the tuple and
# assign it's result to memory - otherwise there is potential for memory corruption
lll_node = Expr(node, self.context).lll_node
target = LLLnode.from_list(
self.context.new_internal_variable(lll_node.typ),
typ=lll_node.typ,
location="memory",
pos=getpos(self.expr),
)
call_lll.append(make_setter(target, lll_node, "memory", pos=getpos(self.expr)))
multi_lll.append(
LLLnode.from_list(
target, typ=lll_node.typ, pos=getpos(self.expr), location="memory"
),
)
else:
multi_lll.append(Expr(node, self.context).lll_node)
typ = TupleType([x.typ for x in multi_lll], is_literal=True)
multi_lll = LLLnode.from_list(["multi"] + multi_lll, typ=typ, pos=getpos(self.expr))
if not call_lll:
return multi_lll
lll_node = ["seq_unchecked"] + call_lll + [multi_lll]
return LLLnode.from_list(lll_node, typ=typ, pos=getpos(self.expr))
def ann_assign(self):
self.context.set_in_assignment(True)
typ = parse_type(self.stmt.annotation,
location='memory',
custom_units=self.context.custom_units)
if isinstance(self.stmt.target,
ast.Attribute) and self.stmt.target.value.id == 'self':
raise TypeMismatchException('May not redefine storage variables.',
self.stmt)
varname = self.stmt.target.id
pos = self.context.new_variable(varname, typ)
o = LLLnode.from_list('pass', typ=None, pos=pos)
if self.stmt.value is not None:
sub = Expr(self.stmt.value, self.context).lll_node
# If bytes[32] to bytes32 assignment rewrite sub as bytes32.
if isinstance(
sub.typ,
ByteArrayType) and sub.typ.maxlen == 32 and isinstance(
typ, BaseType) and typ.typ == 'bytes32':
bytez, bytez_length = string_to_bytes(self.stmt.value.s)
sub = LLLnode(bytes_to_int(bytez),
typ=BaseType('bytes32'),
pos=getpos(self.stmt))
self._check_valid_assign(sub)
self._check_same_variable_assign(sub)
variable_loc = LLLnode.from_list(pos,
typ=typ,
location='memory',
pos=getpos(self.stmt))
o = make_setter(variable_loc, sub, 'memory', pos=getpos(self.stmt))
self.context.set_in_assignment(False)
return o
def ann_assign(self):
self.context.set_in_assignment(True)
typ = parse_type(self.stmt.annotation, location='memory', custom_units=self.context.custom_units, custom_structs=self.context.structs)
if isinstance(self.stmt.target, ast.Attribute):
raise TypeMismatchException('May not set type for field %r' % self.stmt.target.attr, self.stmt)
varname = self.stmt.target.id
pos = self.context.new_variable(varname, typ)
o = LLLnode.from_list('pass', typ=None, pos=pos)
if self.stmt.value is not None:
sub = Expr(self.stmt.value, self.context).lll_node
# Disallow assignment to None
if isinstance(sub.typ, NullType):
raise InvalidLiteralException('Assignment to None is not allowed, use a default value or built-in `clear()`.', self.stmt)
# If bytes[32] to bytes32 assignment rewrite sub as bytes32.
if isinstance(sub.typ, ByteArrayType) and sub.typ.maxlen == 32 and isinstance(typ, BaseType) and typ.typ == 'bytes32':
bytez, bytez_length = string_to_bytes(self.stmt.value.s)
sub = LLLnode(bytes_to_int(bytez), typ=BaseType('bytes32'), pos=getpos(self.stmt))
self._check_valid_assign(sub)
self._check_same_variable_assign(sub)
variable_loc = LLLnode.from_list(pos, typ=typ, location='memory', pos=getpos(self.stmt))
o = make_setter(variable_loc, sub, 'memory', pos=getpos(self.stmt))
# o.pos = getpos(self.stmt) # TODO: Should this be here like in assign()?
self.context.set_in_assignment(False)
return o
def ann_assign(self):
with self.context.assignment_scope():
typ = parse_type(
self.stmt.annotation,
location='memory',
custom_units=self.context.custom_units,
custom_structs=self.context.structs,
constants=self.context.constants,
)
if isinstance(self.stmt.target, ast.Attribute):
raise TypeMismatchException(
f'May not set type for field {self.stmt.target.attr}',
self.stmt,
)
varname = self.stmt.target.id
pos = self.context.new_variable(varname, typ)
o = LLLnode.from_list('pass', typ=None, pos=pos)
if self.stmt.value is None:
raise StructureException(
'New variables must be initialized explicitly',
self.stmt)
sub = Expr(self.stmt.value, self.context).lll_node
# Disallow assignment to None
if isinstance(sub.typ, NullType):
raise InvalidLiteralException(
(
'Assignment to None is not allowed, use a default '
'value or built-in `clear()`.'
),
self.stmt
)
is_valid_bytes32_assign = (
isinstance(sub.typ, ByteArrayType) and sub.typ.maxlen == 32
) and isinstance(typ, BaseType) and typ.typ == 'bytes32'
# If bytes[32] to bytes32 assignment rewrite sub as bytes32.
if is_valid_bytes32_assign:
sub = LLLnode(
bytes_to_int(self.stmt.value.s),
typ=BaseType('bytes32'),
pos=getpos(self.stmt),
)
self._check_valid_assign(sub)
self._check_same_variable_assign(sub)
variable_loc = LLLnode.from_list(
pos,
typ=typ,
location='memory',
pos=getpos(self.stmt),
)
o = make_setter(variable_loc, sub, 'memory', pos=getpos(self.stmt))
# o.pos = getpos(self.stmt) # TODO: Should this be here like in assign()?
return o
def parse_delete(self):
from .parser import (
make_setter,
)
if len(self.stmt.targets) != 1:
raise StructureException("Can delete one variable at a time", self.stmt)
target = self.stmt.targets[0]
target_lll = Expr(self.stmt.targets[0], self.context).lll_node
if isinstance(target, ast.Subscript):
if target_lll.location == "storage":
return make_setter(target_lll, LLLnode.from_list(None, typ=NullType()), "storage", pos=getpos(self.stmt))
raise StructureException("Deleting type not supported.", self.stmt)
def pack_logging_topics(event_id, arg_nodes, arg_types, context):
topics = [event_id]
for node, typ in zip(arg_nodes, arg_types):
value = Expr(node, context).lll_node
if isinstance(typ, ArrayValueAbstractType):
if isinstance(node, (vy_ast.Str, vy_ast.Bytes)):
# for literals, generate the topic at compile time
value = node.value
if isinstance(value, str):
value = value.encode()
topics.append(bytes_to_int(keccak256(value)))
elif value.location == "memory":
topics.append(["sha3", ["add", value, 32], ["mload", value]])
else:
# storage or calldata
placeholder = context.new_internal_variable(value.typ)
placeholder_node = LLLnode.from_list(placeholder, typ=value.typ, location="memory")
copier = make_byte_array_copier(
placeholder_node,
LLLnode.from_list("_sub", typ=value.typ, location=value.location),
)
lll_node = [
"with",
"_sub",
value,
["seq", copier, ["sha3", ["add", placeholder, 32], ["mload", placeholder]]],
]
topics.append(lll_node)
elif isinstance(typ, ArrayDefinition):
size = typ.size_in_bytes
if value.location == "memory":
topics.append(["sha3", value, size])
else:
# storage or calldata
placeholder = context.new_internal_variable(value.typ)
placeholder_node = LLLnode.from_list(placeholder, typ=value.typ, location="memory")
setter = make_setter(placeholder_node, value, "memory", value.pos)
lll_node = ["seq", setter, ["sha3", placeholder, size]]
topics.append(lll_node)
else:
value = unwrap_location(value)
topics.append(value)
return topics
def ann_assign(self):
with self.context.assignment_scope():
typ = parse_type(
self.stmt.annotation,
location='memory',
custom_structs=self.context.structs,
constants=self.context.constants,
)
if isinstance(self.stmt.target, vy_ast.Attribute):
raise TypeMismatch(
f'May not set type for field {self.stmt.target.attr}',
self.stmt,
)
varname = self.stmt.target.id
pos = self.context.new_variable(varname, typ)
if self.stmt.value is None:
raise StructureException(
'New variables must be initialized explicitly',
self.stmt)
sub = Expr(self.stmt.value, self.context).lll_node
is_literal_bytes32_assign = (
isinstance(sub.typ, ByteArrayType)
and sub.typ.maxlen == 32
and isinstance(typ, BaseType)
and typ.typ == 'bytes32'
and sub.typ.is_literal
)
# If bytes[32] to bytes32 assignment rewrite sub as bytes32.
if is_literal_bytes32_assign:
sub = LLLnode(
bytes_to_int(self.stmt.value.s),
typ=BaseType('bytes32'),
pos=getpos(self.stmt),
)
self._check_valid_assign(sub)
self._check_same_variable_assign(sub)
variable_loc = LLLnode.from_list(
pos,
typ=typ,
location='memory',
pos=getpos(self.stmt),
)
o = make_setter(variable_loc, sub, 'memory', pos=getpos(self.stmt))
return o
def ann_assign(self):
self.context.set_in_assignment(True)
typ = parse_type(self.stmt.annotation, location='memory', custom_units=self.context.custom_units)
if isinstance(self.stmt.target, ast.Attribute) and self.stmt.target.value.id == 'self':
raise TypeMismatchException('May not redefine storage variables.', self.stmt)
varname = self.stmt.target.id
pos = self.context.new_variable(varname, typ)
o = LLLnode.from_list('pass', typ=None, pos=pos)
if self.stmt.value is not None:
sub = Expr(self.stmt.value, self.context).lll_node
self._check_valid_assign(sub)
variable_loc = LLLnode.from_list(pos, typ=typ, location='memory', pos=getpos(self.stmt))
o = make_setter(variable_loc, sub, 'memory', pos=getpos(self.stmt))
self.context.set_in_assignment(False)
return o
def _clear(self):
# Create zero node
none = ast.NameConstant(None)
none.lineno = self.stmt.lineno
none.col_offset = self.stmt.col_offset
zero = Expr(none, self.context).lll_node
# Get target variable
target = self.get_target(self.stmt.args[0])
# Generate LLL node to set to zero
o = make_setter(target, zero, target.location, pos=getpos(self.stmt))
o.pos = getpos(self.stmt)
return o
def assign(self):
# Assignment (e.g. x[4] = y)
with self.context.assignment_scope():
sub = Expr(self.stmt.value, self.context).lll_node
# Error check when assigning to declared variable
if isinstance(self.stmt.target, vy_ast.Name):
# Do not allow assignment to undefined variables without annotation
if self.stmt.target.id not in self.context.vars:
raise VariableDeclarationException(
"Variable type not defined", self.stmt)
# Check against implicit conversion
self._check_implicit_conversion(self.stmt.target.id, sub)
is_valid_tuple_assign = (isinstance(
self.stmt.target, vy_ast.Tuple)) and isinstance(
self.stmt.value, vy_ast.Tuple)
# Do no allow tuple-to-tuple assignment
if is_valid_tuple_assign:
raise VariableDeclarationException(
"Tuple to tuple assignment not supported",
self.stmt,
)
# Checks to see if assignment is valid
target = self.get_target(self.stmt.target)
if isinstance(target.typ, ContractType) and not isinstance(
sub.typ, ContractType):
raise TypeMismatch(
'Contract assignment expects casted address: '
f'{target.typ}(<address_var>)', self.stmt)
o = make_setter(target,
sub,
target.location,
pos=getpos(self.stmt))
o.pos = getpos(self.stmt)
return o
def parse_func(code, sigs, origcode, global_ctx, _vars=None):
if _vars is None:
_vars = {}
sig = FunctionSignature.from_definition(
code,
sigs=sigs,
custom_units=global_ctx._custom_units,
custom_structs=global_ctx._structs,
constants=global_ctx._constants)
# Get base args for function.
total_default_args = len(code.args.defaults)
base_args = sig.args[:
-total_default_args] if total_default_args > 0 else sig.args
default_args = code.args.args[-total_default_args:]
default_values = dict(
zip([arg.arg for arg in default_args], code.args.defaults))
# __init__ function may not have defaults.
if sig.name == '__init__' and total_default_args > 0:
raise FunctionDeclarationException(
"__init__ function may not have default parameters.")
# Check for duplicate variables with globals
for arg in sig.args:
if arg.name in global_ctx._globals:
raise FunctionDeclarationException(
"Variable name duplicated between function arguments and globals: "
+ arg.name)
nonreentrant_pre = [['pass']]
nonreentrant_post = [['pass']]
if sig.nonreentrant_key:
nkey = global_ctx.get_nonrentrant_counter(sig.nonreentrant_key)
nonreentrant_pre = [[
'seq', ['assert', ['iszero', ['sload', nkey]]],
['sstore', nkey, 1]
]]
nonreentrant_post = [['sstore', nkey, 0]]
# Create a local (per function) context.
context = Context(
vars=_vars,
global_ctx=global_ctx,
sigs=sigs,
return_type=sig.output_type,
constancy=Constancy.Constant if sig.const else Constancy.Mutable,
is_payable=sig.payable,
origcode=origcode,
is_private=sig.private,
method_id=sig.method_id)
# Copy calldata to memory for fixed-size arguments
max_copy_size = sum([
32 if isinstance(arg.typ, ByteArrayLike) else
get_size_of_type(arg.typ) * 32 for arg in sig.args
])
base_copy_size = sum([
32 if isinstance(arg.typ, ByteArrayLike) else
get_size_of_type(arg.typ) * 32 for arg in base_args
])
context.next_mem += max_copy_size
clampers = []
# Create callback_ptr, this stores a destination in the bytecode for a private
# function to jump to after a function has executed.
_post_callback_ptr = "{}_{}_post_callback_ptr".format(
sig.name, sig.method_id)
if sig.private:
context.callback_ptr = context.new_placeholder(typ=BaseType('uint256'))
clampers.append(
LLLnode.from_list(
['mstore', context.callback_ptr, 'pass'],
annotation='pop callback pointer',
))
if total_default_args > 0:
clampers.append(['label', _post_callback_ptr])
# private functions without return types need to jump back to
# the calling function, as there is no return statement to handle the
# jump.
stop_func = [['stop']]
if sig.output_type is None and sig.private:
stop_func = [['jump', ['mload', context.callback_ptr]]]
if not len(base_args):
copier = 'pass'
elif sig.name == '__init__':
copier = [
'codecopy', MemoryPositions.RESERVED_MEMORY, '~codelen',
base_copy_size
]
else:
copier = get_arg_copier(sig=sig,
total_size=base_copy_size,
memory_dest=MemoryPositions.RESERVED_MEMORY)
clampers.append(copier)
# Add asserts for payable and internal
# private never gets payable check.
if not sig.payable and not sig.private:
clampers.append(['assert', ['iszero', 'callvalue']])
# Fill variable positions
for i, arg in enumerate(sig.args):
if i < len(base_args) and not sig.private:
clampers.append(
make_clamper(
arg.pos,
context.next_mem,
arg.typ,
sig.name == '__init__',
))
if isinstance(arg.typ, ByteArrayLike):
context.vars[arg.name] = VariableRecord(arg.name, context.next_mem,
arg.typ, False)
context.next_mem += 32 * get_size_of_type(arg.typ)
else:
context.vars[arg.name] = VariableRecord(
arg.name,
MemoryPositions.RESERVED_MEMORY + arg.pos,
arg.typ,
False,
)
# Private function copiers. No clamping for private functions.
dyn_variable_names = [
a.name for a in base_args if isinstance(a.typ, ByteArrayLike)
]
if sig.private and dyn_variable_names:
i_placeholder = context.new_placeholder(typ=BaseType('uint256'))
unpackers = []
for idx, var_name in enumerate(dyn_variable_names):
var = context.vars[var_name]
ident = "_load_args_%d_dynarg%d" % (sig.method_id, idx)
o = make_unpacker(ident=ident,
i_placeholder=i_placeholder,
begin_pos=var.pos)
unpackers.append(o)
if not unpackers:
unpackers = ['pass']
clampers.append(
LLLnode.from_list(
# [0] to complete full overarching 'seq' statement, see private_label.
['seq_unchecked'] + unpackers + [0],
typ=None,
annotation='dynamic unpacker',
pos=getpos(code),
))
# Create "clampers" (input well-formedness checkers)
# Return function body
if sig.name == '__init__':
o = LLLnode.from_list(
['seq'] + clampers + [parse_body(code.body, context)],
pos=getpos(code),
)
elif is_default_func(sig):
if len(sig.args) > 0:
raise FunctionDeclarationException(
'Default function may not receive any arguments.', code)
if sig.private:
raise FunctionDeclarationException(
'Default function may only be public.',
code,
)
o = LLLnode.from_list(
['seq'] + clampers + [parse_body(code.body, context)],
pos=getpos(code),
)
else:
if total_default_args > 0: # Function with default parameters.
function_routine = "{}_{}".format(sig.name, sig.method_id)
default_sigs = generate_default_arg_sigs(code, sigs, global_ctx)
sig_chain = ['seq']
for default_sig in default_sigs:
sig_compare, private_label = get_sig_statements(
default_sig, getpos(code))
# Populate unset default variables
populate_arg_count = len(sig.args) - len(default_sig.args)
set_defaults = []
if populate_arg_count > 0:
current_sig_arg_names = {x.name for x in default_sig.args}
missing_arg_names = [
arg.arg for arg in default_args
if arg.arg not in current_sig_arg_names
]
for arg_name in missing_arg_names:
value = Expr(default_values[arg_name],
context).lll_node
var = context.vars[arg_name]
left = LLLnode.from_list(var.pos,
typ=var.typ,
location='memory',
pos=getpos(code),
mutable=var.mutable)
set_defaults.append(
make_setter(left,
value,
'memory',
pos=getpos(code)))
current_sig_arg_names = {x.name for x in default_sig.args}
base_arg_names = {arg.name for arg in base_args}
if sig.private:
# Load all variables in default section, if private,
# because the stack is a linear pipe.
copier_arg_count = len(default_sig.args)
copier_arg_names = current_sig_arg_names
else:
copier_arg_count = len(default_sig.args) - len(base_args)
copier_arg_names = current_sig_arg_names - base_arg_names
# Order copier_arg_names, this is very important.
copier_arg_names = [
x.name for x in default_sig.args
if x.name in copier_arg_names
]
# Variables to be populated from calldata/stack.
default_copiers = []
if copier_arg_count > 0:
# Get map of variables in calldata, with thier offsets
offset = 4
calldata_offset_map = {}
for arg in default_sig.args:
calldata_offset_map[arg.name] = offset
offset += (32 if isinstance(arg.typ, ByteArrayLike)
else get_size_of_type(arg.typ) * 32)
# Copy set default parameters from calldata
dynamics = []
for arg_name in copier_arg_names:
var = context.vars[arg_name]
calldata_offset = calldata_offset_map[arg_name]
if sig.private:
_offset = calldata_offset
if isinstance(var.typ, ByteArrayLike):
_size = 32
dynamics.append(var.pos)
else:
_size = var.size * 32
default_copiers.append(
get_arg_copier(
sig=sig,
memory_dest=var.pos,
total_size=_size,
offset=_offset,
))
else:
# Add clampers.
default_copiers.append(
make_clamper(
calldata_offset - 4,
var.pos,
var.typ,
))
# Add copying code.
if isinstance(var.typ, ByteArrayLike):
_offset = [
'add', 4,
['calldataload', calldata_offset]
]
else:
_offset = calldata_offset
default_copiers.append(
get_arg_copier(
sig=sig,
memory_dest=var.pos,
total_size=var.size * 32,
offset=_offset,
))
# Unpack byte array if necessary.
if dynamics:
i_placeholder = context.new_placeholder(
typ=BaseType('uint256'))
for idx, var_pos in enumerate(dynamics):
ident = 'unpack_default_sig_dyn_%d_arg%d' % (
default_sig.method_id, idx)
default_copiers.append(
make_unpacker(
ident=ident,
i_placeholder=i_placeholder,
begin_pos=var_pos,
))
default_copiers.append(0) # for over arching seq, POP
sig_chain.append([
'if', sig_compare,
[
'seq', private_label, ['pass'] if not sig.private else
LLLnode.from_list([
'mstore',
context.callback_ptr,
'pass',
],
annotation='pop callback pointer',
pos=getpos(code)),
['seq'] + set_defaults if set_defaults else ['pass'],
['seq_unchecked'] +
default_copiers if default_copiers else ['pass'],
[
'goto', _post_callback_ptr
if sig.private else function_routine
]
]
])
# With private functions all variable loading occurs in the default
# function sub routine.
if sig.private:
_clampers = [['label', _post_callback_ptr]]
else:
_clampers = clampers
# Function with default parameters.
o = LLLnode.from_list(
[
'seq',
sig_chain,
[
'if',
0, # can only be jumped into
[
'seq', ['label', function_routine]
if not sig.private else ['pass'],
['seq'] + nonreentrant_pre + _clampers +
[parse_body(c, context) for c in code.body] +
nonreentrant_post + stop_func
],
],
],
typ=None,
pos=getpos(code))
else:
# Function without default parameters.
sig_compare, private_label = get_sig_statements(sig, getpos(code))
o = LLLnode.from_list([
'if', sig_compare,
['seq'] + [private_label] + nonreentrant_pre + clampers +
[parse_body(c, context)
for c in code.body] + nonreentrant_post + stop_func
],
typ=None,
pos=getpos(code))
# Check for at leasts one return statement if necessary.
if context.return_type and context.function_return_count == 0:
raise FunctionDeclarationException(
"Missing return statement in function '%s' " % sig.name, code)
o.context = context
o.total_gas = o.gas + calc_mem_gas(o.context.next_mem)
o.func_name = sig.name
return o
def parse_return(self):
if self.context.return_type is None:
if self.stmt.value:
raise TypeMismatchException("Not expecting to return a value",
self.stmt)
return LLLnode.from_list(make_return_stmt(self.stmt, self.context,
0, 0),
typ=None,
pos=getpos(self.stmt),
valency=0)
if not self.stmt.value:
raise TypeMismatchException("Expecting to return a value",
self.stmt)
def zero_pad(bytez_placeholder, maxlen):
zero_padder = LLLnode.from_list(['pass'])
if maxlen > 0:
zero_pad_i = self.context.new_placeholder(
BaseType('uint256')) # Iterator used to zero pad memory.
zero_padder = LLLnode.from_list(
[
'with',
'_ceil32_end',
['ceil32', ['mload', bytez_placeholder]],
[
'repeat',
zero_pad_i,
['mload', bytez_placeholder],
maxlen,
[
'seq',
[
'if',
[
'gt', ['mload', zero_pad_i],
'_ceil32_end'
], 'break'
], # stay within allocated bounds
[
'mstore8',
[
'add', ['add', 32, bytez_placeholder],
['mload', zero_pad_i]
], 0
]
]
]
],
annotation="Zero pad")
return zero_padder
sub = Expr(self.stmt.value, self.context).lll_node
self.context.increment_return_counter()
# Returning a value (most common case)
if isinstance(sub.typ, BaseType):
sub = unwrap_location(sub)
if not isinstance(self.context.return_type, BaseType):
raise TypeMismatchException(
"Return type units mismatch %r %r" %
(sub.typ, self.context.return_type), self.stmt.value)
elif self.context.return_type != sub.typ and not sub.typ.is_literal:
raise TypeMismatchException(
"Trying to return base type %r, output expecting %r" %
(sub.typ, self.context.return_type), self.stmt.value)
elif sub.typ.is_literal and (
self.context.return_type.typ == sub.typ or 'int'
in self.context.return_type.typ and 'int' in sub.typ.typ):
if not SizeLimits.in_bounds(self.context.return_type.typ,
sub.value):
raise InvalidLiteralException(
"Number out of range: " + str(sub.value), self.stmt)
else:
return LLLnode.from_list([
'seq', ['mstore', 0, sub],
make_return_stmt(self.stmt, self.context, 0, 32)
],
typ=None,
pos=getpos(self.stmt),
valency=0)
elif is_base_type(sub.typ, self.context.return_type.typ) or \
(is_base_type(sub.typ, 'int128') and is_base_type(self.context.return_type, 'int256')):
return LLLnode.from_list([
'seq', ['mstore', 0, sub],
make_return_stmt(self.stmt, self.context, 0, 32)
],
typ=None,
pos=getpos(self.stmt),
valency=0)
else:
raise TypeMismatchException(
"Unsupported type conversion: %r to %r" %
(sub.typ, self.context.return_type), self.stmt.value)
# Returning a byte array
elif isinstance(sub.typ, ByteArrayLike):
if not sub.typ.eq_base(self.context.return_type):
raise TypeMismatchException(
"Trying to return base type %r, output expecting %r" %
(sub.typ, self.context.return_type), self.stmt.value)
if sub.typ.maxlen > self.context.return_type.maxlen:
raise TypeMismatchException(
"Cannot cast from greater max-length %d to shorter max-length %d"
% (sub.typ.maxlen, self.context.return_type.maxlen),
self.stmt.value)
loop_memory_position = self.context.new_placeholder(
typ=BaseType(
'uint256')) # loop memory has to be allocated first.
len_placeholder = self.context.new_placeholder(
typ=BaseType('uint256')
) # len & bytez placeholder have to be declared after each other at all times.
bytez_placeholder = self.context.new_placeholder(typ=sub.typ)
if sub.location in ('storage', 'memory'):
return LLLnode.from_list([
'seq',
make_byte_array_copier(LLLnode(
bytez_placeholder, location='memory', typ=sub.typ),
sub,
pos=getpos(self.stmt)),
zero_pad(bytez_placeholder, sub.typ.maxlen),
['mstore', len_placeholder, 32],
make_return_stmt(
self.stmt,
self.context,
len_placeholder,
['ceil32', ['add', ['mload', bytez_placeholder], 64]],
loop_memory_position=loop_memory_position)
],
typ=None,
pos=getpos(self.stmt),
valency=0)
else:
raise Exception("Invalid location: %s" % sub.location)
elif isinstance(sub.typ, ListType):
sub_base_type = re.split(r'\(|\[', str(sub.typ.subtype))[0]
ret_base_type = re.split(r'\(|\[',
str(self.context.return_type.subtype))[0]
loop_memory_position = self.context.new_placeholder(
typ=BaseType('uint256'))
if sub_base_type != ret_base_type:
raise TypeMismatchException(
"List return type %r does not match specified return type, expecting %r"
% (sub_base_type, ret_base_type), self.stmt)
elif sub.location == "memory" and sub.value != "multi":
return LLLnode.from_list(make_return_stmt(
self.stmt,
self.context,
sub,
get_size_of_type(self.context.return_type) * 32,
loop_memory_position=loop_memory_position),
typ=None,
pos=getpos(self.stmt),
valency=0)
else:
new_sub = LLLnode.from_list(self.context.new_placeholder(
self.context.return_type),
typ=self.context.return_type,
location='memory')
setter = make_setter(new_sub,
sub,
'memory',
pos=getpos(self.stmt))
return LLLnode.from_list([
'seq', setter,
make_return_stmt(
self.stmt,
self.context,
new_sub,
get_size_of_type(self.context.return_type) * 32,
loop_memory_position=loop_memory_position)
],
typ=None,
pos=getpos(self.stmt))
# Returning a struct
elif isinstance(sub.typ, StructType):
retty = self.context.return_type
if not isinstance(retty, StructType) or retty.name != sub.typ.name:
raise TypeMismatchException(
"Trying to return %r, output expecting %r" %
(sub.typ, self.context.return_type), self.stmt.value)
return gen_tuple_return(self.stmt, self.context, sub)
# Returning a tuple.
elif isinstance(sub.typ, TupleType):
if not isinstance(self.context.return_type, TupleType):
raise TypeMismatchException(
"Trying to return tuple type %r, output expecting %r" %
(sub.typ, self.context.return_type), self.stmt.value)
if len(self.context.return_type.members) != len(sub.typ.members):
raise StructureException("Tuple lengths don't match!",
self.stmt)
# check return type matches, sub type.
for i, ret_x in enumerate(self.context.return_type.members):
s_member = sub.typ.members[i]
sub_type = s_member if isinstance(s_member,
NodeType) else s_member.typ
if type(sub_type) is not type(ret_x):
raise StructureException(
"Tuple return type does not match annotated return. {} != {}"
.format(type(sub_type), type(ret_x)), self.stmt)
return gen_tuple_return(self.stmt, self.context, sub)
else:
raise TypeMismatchException("Can't return type %r" % sub.typ,
self.stmt)
def parse_for_list(self):
from .parser import (parse_body, make_setter)
iter_list_node = Expr(self.stmt.iter, self.context).lll_node
if not isinstance(iter_list_node.typ.subtype,
BaseType): # Sanity check on list subtype.
raise StructureException(
'For loops allowed only on basetype lists.', self.stmt.iter)
iter_var_type = self.context.vars.get(
self.stmt.iter.id).typ if isinstance(self.stmt.iter,
ast.Name) else None
subtype = iter_list_node.typ.subtype.typ
varname = self.stmt.target.id
value_pos = self.context.new_variable(
varname, BaseType(subtype, unit=iter_list_node.typ.subtype.unit))
i_pos = self.context.new_variable('_index_for_' + varname,
BaseType(subtype))
self.context.forvars[varname] = True
# Is a list that is already allocated to memory.
if iter_var_type:
list_name = self.stmt.iter.id
with self.context.in_for_loop_scope(
list_name
): # make sure list cannot be altered whilst iterating.
iter_var = self.context.vars.get(self.stmt.iter.id)
body = [
'seq',
[
'mstore', value_pos,
[
'mload',
[
'add', iter_var.pos,
['mul', ['mload', i_pos], 32]
]
]
],
parse_body(self.stmt.body, self.context)
]
o = LLLnode.from_list(
['repeat', i_pos, 0, iter_var.size, body],
typ=None,
pos=getpos(self.stmt))
# List gets defined in the for statement.
elif isinstance(self.stmt.iter, ast.List):
# Allocate list to memory.
count = iter_list_node.typ.count
tmp_list = LLLnode.from_list(obj=self.context.new_placeholder(
ListType(iter_list_node.typ.subtype, count)),
typ=ListType(
iter_list_node.typ.subtype,
count),
location='memory')
setter = make_setter(tmp_list,
iter_list_node,
'memory',
pos=getpos(self.stmt))
body = [
'seq',
[
'mstore', value_pos,
[
'mload',
['add', tmp_list, ['mul', ['mload', i_pos], 32]]
]
],
parse_body(self.stmt.body, self.context)
]
o = LLLnode.from_list(
['seq', setter, ['repeat', i_pos, 0, count, body]],
typ=None,
pos=getpos(self.stmt))
# List contained in storage.
elif isinstance(self.stmt.iter, ast.Attribute):
count = iter_list_node.typ.count
list_name = iter_list_node.annotation
with self.context.in_for_loop_scope(
list_name
): # make sure list cannot be altered whilst iterating.
body = [
'seq',
[
'mstore', value_pos,
[
'sload',
[
'add', ['sha3_32', iter_list_node],
['mload', i_pos]
]
]
],
parse_body(self.stmt.body, self.context),
]
o = LLLnode.from_list(
['seq', ['repeat', i_pos, 0, count, body]],
typ=None,
pos=getpos(self.stmt))
del self.context.vars[varname]
del self.context.vars['_index_for_' + varname]
del self.context.forvars[varname]
return o
def parse_private_function(code: ast.FunctionDef, sig: FunctionSignature,
context: Context) -> LLLnode:
"""
Parse a private function (FuncDef), and produce full function body.
:param sig: the FuntionSignature
:param code: ast of function
:return: full sig compare & function body
"""
validate_private_function(code, sig)
# Get nonreentrant lock
nonreentrant_pre, nonreentrant_post = get_nonreentrant_lock(
sig, context.global_ctx)
# Create callback_ptr, this stores a destination in the bytecode for a private
# function to jump to after a function has executed.
clampers: List[LLLnode] = []
# Allocate variable space.
context.memory_allocator.increase_memory(sig.max_copy_size)
_post_callback_ptr = f"{sig.name}_{sig.method_id}_post_callback_ptr"
context.callback_ptr = context.new_placeholder(typ=BaseType('uint256'))
clampers.append(
LLLnode.from_list(
['mstore', context.callback_ptr, 'pass'],
annotation='pop callback pointer',
))
if sig.total_default_args > 0:
clampers.append(LLLnode.from_list(['label', _post_callback_ptr]))
# private functions without return types need to jump back to
# the calling function, as there is no return statement to handle the
# jump.
if sig.output_type is None:
stop_func = [['jump', ['mload', context.callback_ptr]]]
else:
stop_func = [['stop']]
# Generate copiers
if len(sig.base_args) == 0:
copier = ['pass']
clampers.append(LLLnode.from_list(copier))
elif sig.total_default_args == 0:
copier = get_private_arg_copier(
total_size=sig.base_copy_size,
memory_dest=MemoryPositions.RESERVED_MEMORY)
clampers.append(LLLnode.from_list(copier))
# Fill variable positions
for arg in sig.args:
if isinstance(arg.typ, ByteArrayLike):
mem_pos, _ = context.memory_allocator.increase_memory(
32 * get_size_of_type(arg.typ))
context.vars[arg.name] = VariableRecord(arg.name, mem_pos, arg.typ,
False)
else:
context.vars[arg.name] = VariableRecord(
arg.name,
MemoryPositions.RESERVED_MEMORY + arg.pos,
arg.typ,
False,
)
# Private function copiers. No clamping for private functions.
dyn_variable_names = [
a.name for a in sig.base_args if isinstance(a.typ, ByteArrayLike)
]
if dyn_variable_names:
i_placeholder = context.new_placeholder(typ=BaseType('uint256'))
unpackers: List[Any] = []
for idx, var_name in enumerate(dyn_variable_names):
var = context.vars[var_name]
ident = f"_load_args_{sig.method_id}_dynarg{idx}"
o = make_unpacker(ident=ident,
i_placeholder=i_placeholder,
begin_pos=var.pos)
unpackers.append(o)
if not unpackers:
unpackers = ['pass']
# 0 added to complete full overarching 'seq' statement, see private_label.
unpackers.append(0)
clampers.append(
LLLnode.from_list(
['seq_unchecked'] + unpackers,
typ=None,
annotation='dynamic unpacker',
pos=getpos(code),
))
# Function has default arguments.
if sig.total_default_args > 0: # Function with default parameters.
default_sigs = sig_utils.generate_default_arg_sigs(
code, context.sigs, context.global_ctx)
sig_chain: List[Any] = ['seq']
for default_sig in default_sigs:
sig_compare, private_label = get_sig_statements(
default_sig, getpos(code))
# Populate unset default variables
set_defaults = []
for arg_name in get_default_names_to_set(sig, default_sig):
value = Expr(sig.default_values[arg_name], context).lll_node
var = context.vars[arg_name]
left = LLLnode.from_list(var.pos,
typ=var.typ,
location='memory',
pos=getpos(code),
mutable=var.mutable)
set_defaults.append(
make_setter(left, value, 'memory', pos=getpos(code)))
current_sig_arg_names = [x.name for x in default_sig.args]
# Load all variables in default section, if private,
# because the stack is a linear pipe.
copier_arg_count = len(default_sig.args)
copier_arg_names = current_sig_arg_names
# Order copier_arg_names, this is very important.
copier_arg_names = [
x.name for x in default_sig.args if x.name in copier_arg_names
]
# Variables to be populated from calldata/stack.
default_copiers: List[Any] = []
if copier_arg_count > 0:
# Get map of variables in calldata, with thier offsets
offset = 4
calldata_offset_map = {}
for arg in default_sig.args:
calldata_offset_map[arg.name] = offset
offset += (32 if isinstance(arg.typ, ByteArrayLike) else
get_size_of_type(arg.typ) * 32)
# Copy set default parameters from calldata
dynamics = []
for arg_name in copier_arg_names:
var = context.vars[arg_name]
if isinstance(var.typ, ByteArrayLike):
_size = 32
dynamics.append(var.pos)
else:
_size = var.size * 32
default_copiers.append(
get_private_arg_copier(
memory_dest=var.pos,
total_size=_size,
))
# Unpack byte array if necessary.
if dynamics:
i_placeholder = context.new_placeholder(
typ=BaseType('uint256'))
for idx, var_pos in enumerate(dynamics):
ident = f'unpack_default_sig_dyn_{default_sig.method_id}_arg{idx}'
default_copiers.append(
make_unpacker(
ident=ident,
i_placeholder=i_placeholder,
begin_pos=var_pos,
))
default_copiers.append(0) # for over arching seq, POP
sig_chain.append([
'if', sig_compare,
[
'seq', private_label,
LLLnode.from_list([
'mstore',
context.callback_ptr,
'pass',
],
annotation='pop callback pointer',
pos=getpos(code)),
['seq'] + set_defaults if set_defaults else ['pass'],
['seq_unchecked'] +
default_copiers if default_copiers else ['pass'],
['goto', _post_callback_ptr]
]
])
# With private functions all variable loading occurs in the default
# function sub routine.
_clampers = [['label', _post_callback_ptr]]
# Function with default parameters.
o = LLLnode.from_list(
[
'seq',
sig_chain,
[
'if',
0, # can only be jumped into
[
'seq', ['seq'] + nonreentrant_pre + _clampers +
[parse_body(c, context)
for c in code.body] + nonreentrant_post + stop_func
],
],
],
typ=None,
pos=getpos(code))
else:
# Function without default parameters.
sig_compare, private_label = get_sig_statements(sig, getpos(code))
o = LLLnode.from_list([
'if', sig_compare, ['seq'] + [private_label] + nonreentrant_pre +
clampers + [parse_body(c, context)
for c in code.body] + nonreentrant_post + stop_func
],
typ=None,
pos=getpos(code))
return o
return o
def build_in_comparator(self):
left = Expr(self.expr.left, self.context).lll_node
right = Expr(self.expr.right, self.context).lll_node
result_placeholder = self.context.new_internal_variable(
BaseType("bool"))
setter = []
# Load nth item from list in memory.
if right.value == "multi":
# Copy literal to memory to be compared.
tmp_list = LLLnode.from_list(
obj=self.context.new_internal_variable(
ListType(right.typ.subtype, right.typ.count)),
typ=ListType(right.typ.subtype, right.typ.count),
location="memory",
)
setter = make_setter(tmp_list,
right,
"memory",
pos=getpos(self.expr))
load_i_from_list = [
"mload",
[
"add", tmp_list,
["mul", 32, ["mload", MemoryPositions.FREE_LOOP_INDEX]]
],
]
elif right.location == "storage":
load_i_from_list = [
"sload",
["add", right, ["mload", MemoryPositions.FREE_LOOP_INDEX]],
]
else:
load_operation = "mload" if right.location == "memory" else "calldataload"
load_i_from_list = [
load_operation,
[
"add", right,
["mul", 32, ["mload", MemoryPositions.FREE_LOOP_INDEX]]
],
]
# Condition repeat loop has to break on.
break_loop_condition = [
"if",
["eq", unwrap_location(left), load_i_from_list],
["seq", ["mstore", "_result", 1], "break"], # store true.
]
# Repeat loop to loop-compare each item in the list.
for_loop_sequence = [
["mstore", result_placeholder, 0],
[
"with",
"_result",
result_placeholder,
[
"repeat",
MemoryPositions.FREE_LOOP_INDEX,
0,
right.typ.count,
break_loop_condition,
],
],
["mload", result_placeholder],
]
# Save list to memory, so one can iterate over it,
# used when literal was created with tmp_list.
if setter:
compare_sequence = ["seq", setter] + for_loop_sequence
else:
compare_sequence = ["seq"] + for_loop_sequence
if isinstance(self.expr.op, vy_ast.NotIn):
# for `not in`, invert the result
compare_sequence = ["iszero", compare_sequence]
return LLLnode.from_list(compare_sequence,
typ="bool",
annotation="in comparator")
def parse_sequence(base_node, elements, context):
"""
Generate an LLL node from a sequence of Vyper AST nodes, such as values inside a
list/tuple or arguments inside a call.
Arguments
---------
base_node : VyperNode
Parent node which contains the sequence being parsed.
elements : List[VyperNode]
A list of nodes within the sequence.
context : Context
Currently active local context.
Returns
-------
List[LLLNode]
LLL nodes that must execute prior to generating the actual sequence in order to
avoid memory corruption issues. This list may be empty, depending on the values
within `elements`.
List[LLLNode]
LLL nodes which collectively represent `elements`.
"""
init_lll = []
sequence_lll = []
for node in elements:
if isinstance(node, vy_ast.List):
# for nested lists, ensure the init LLL is also processed before the values
init, seq = parse_sequence(node, node.elements, context)
init_lll.extend(init)
out_type = next((i.typ for i in seq if not i.typ.is_literal),
seq[0].typ)
typ = ListType(out_type, len(node.elements), is_literal=True)
multi_lll = LLLnode.from_list(["multi"] + seq,
typ=typ,
pos=getpos(node))
sequence_lll.append(multi_lll)
continue
lll_node = Expr(node, context).lll_node
if isinstance(
node,
vy_ast.Call) or (isinstance(node, vy_ast.Subscript)
and isinstance(node.value, vy_ast.Call)):
# nodes which potentially create their own internal memory variables, and so must
# be parsed prior to generating the final sequence to avoid memory corruption
target = LLLnode.from_list(
context.new_internal_variable(lll_node.typ),
typ=lll_node.typ,
location="memory",
pos=getpos(base_node),
)
init_lll.append(
make_setter(target, lll_node, "memory", pos=getpos(base_node)))
sequence_lll.append(
LLLnode.from_list(target,
typ=lll_node.typ,
pos=getpos(base_node),
location="memory"), )
else:
sequence_lll.append(lll_node)
return init_lll, sequence_lll
def parse_return(self):
if self.context.return_type is None:
if self.stmt.value:
raise TypeMismatchException("Not expecting to return a value",
self.stmt)
return LLLnode.from_list(self.make_return_stmt(0, 0),
typ=None,
pos=getpos(self.stmt),
valency=0)
if not self.stmt.value:
raise TypeMismatchException("Expecting to return a value",
self.stmt)
def zero_pad(bytez_placeholder, maxlen):
zero_padder = LLLnode.from_list(['pass'])
if maxlen > 0:
zero_pad_i = self.context.new_placeholder(
BaseType('uint256')) # Iterator used to zero pad memory.
zero_padder = LLLnode.from_list(
[
'repeat',
zero_pad_i,
['mload', bytez_placeholder],
maxlen,
[
'seq',
[
'if', ['gt', ['mload', zero_pad_i], maxlen],
'break'
], # stay within allocated bounds
[
'mstore8',
[
'add', ['add', 32, bytez_placeholder],
['mload', zero_pad_i]
], 0
]
]
],
annotation="Zero pad")
return zero_padder
sub = Expr(self.stmt.value, self.context).lll_node
self.context.increment_return_counter()
# Returning a value (most common case)
if isinstance(sub.typ, BaseType):
if not isinstance(self.context.return_type, BaseType):
raise TypeMismatchException(
"Trying to return base type %r, output expecting %r" %
(sub.typ, self.context.return_type), self.stmt.value)
sub = unwrap_location(sub)
if not are_units_compatible(sub.typ, self.context.return_type):
raise TypeMismatchException(
"Return type units mismatch %r %r" %
(sub.typ, self.context.return_type), self.stmt.value)
elif sub.typ.is_literal and (
self.context.return_type.typ == sub.typ or 'int'
in self.context.return_type.typ and 'int' in sub.typ.typ):
if not SizeLimits.in_bounds(self.context.return_type.typ,
sub.value):
raise InvalidLiteralException(
"Number out of range: " + str(sub.value), self.stmt)
else:
return LLLnode.from_list([
'seq', ['mstore', 0, sub],
self.make_return_stmt(0, 32)
],
typ=None,
pos=getpos(self.stmt),
valency=0)
elif is_base_type(sub.typ, self.context.return_type.typ) or \
(is_base_type(sub.typ, 'int128') and is_base_type(self.context.return_type, 'int256')):
return LLLnode.from_list(
['seq', ['mstore', 0, sub],
self.make_return_stmt(0, 32)],
typ=None,
pos=getpos(self.stmt),
valency=0)
else:
raise TypeMismatchException(
"Unsupported type conversion: %r to %r" %
(sub.typ, self.context.return_type), self.stmt.value)
# Returning a byte array
elif isinstance(sub.typ, ByteArrayType):
if not isinstance(self.context.return_type, ByteArrayType):
raise TypeMismatchException(
"Trying to return base type %r, output expecting %r" %
(sub.typ, self.context.return_type), self.stmt.value)
if sub.typ.maxlen > self.context.return_type.maxlen:
raise TypeMismatchException(
"Cannot cast from greater max-length %d to shorter max-length %d"
% (sub.typ.maxlen, self.context.return_type.maxlen),
self.stmt.value)
loop_memory_position = self.context.new_placeholder(
typ=BaseType(
'uint256')) # loop memory has to be allocated first.
len_placeholder = self.context.new_placeholder(
typ=BaseType('uint256')
) # len & bytez placeholder have to be declared after each other at all times.
bytez_placeholder = self.context.new_placeholder(typ=sub.typ)
if sub.location in ('storage', 'memory'):
return LLLnode.from_list([
'seq',
make_byte_array_copier(LLLnode(
bytez_placeholder, location='memory', typ=sub.typ),
sub,
pos=getpos(self.stmt)),
zero_pad(bytez_placeholder, sub.typ.maxlen),
['mstore', len_placeholder, 32],
self.make_return_stmt(
len_placeholder,
['ceil32', ['add', ['mload', bytez_placeholder], 64]],
loop_memory_position=loop_memory_position)
],
typ=None,
pos=getpos(self.stmt),
valency=0)
else:
raise Exception("Invalid location: %s" % sub.location)
elif isinstance(sub.typ, ListType):
sub_base_type = re.split(r'\(|\[', str(sub.typ.subtype))[0]
ret_base_type = re.split(r'\(|\[',
str(self.context.return_type.subtype))[0]
loop_memory_position = self.context.new_placeholder(
typ=BaseType('uint256'))
if sub_base_type != ret_base_type:
raise TypeMismatchException(
"List return type %r does not match specified return type, expecting %r"
% (sub_base_type, ret_base_type), self.stmt)
elif sub.location == "memory" and sub.value != "multi":
return LLLnode.from_list(self.make_return_stmt(
sub,
get_size_of_type(self.context.return_type) * 32,
loop_memory_position=loop_memory_position),
typ=None,
pos=getpos(self.stmt),
valency=0)
else:
new_sub = LLLnode.from_list(self.context.new_placeholder(
self.context.return_type),
typ=self.context.return_type,
location='memory')
setter = make_setter(new_sub,
sub,
'memory',
pos=getpos(self.stmt))
return LLLnode.from_list([
'seq', setter,
self.make_return_stmt(
new_sub,
get_size_of_type(self.context.return_type) * 32,
loop_memory_position=loop_memory_position)
],
typ=None,
pos=getpos(self.stmt))
# Returning a tuple.
elif isinstance(sub.typ, TupleType):
if not isinstance(self.context.return_type, TupleType):
raise TypeMismatchException(
"Trying to return tuple type %r, output expecting %r" %
(sub.typ, self.context.return_type), self.stmt.value)
if len(self.context.return_type.members) != len(sub.typ.members):
raise StructureException("Tuple lengths don't match!",
self.stmt)
# check return type matches, sub type.
for i, ret_x in enumerate(self.context.return_type.members):
s_member = sub.typ.members[i]
sub_type = s_member if isinstance(s_member,
NodeType) else s_member.typ
if type(sub_type) is not type(ret_x):
raise StructureException(
"Tuple return type does not match annotated return. {} != {}"
.format(type(sub_type), type(ret_x)), self.stmt)
# Is from a call expression.
if len(sub.args[0].args) > 0 and sub.args[0].args[
0].value == 'call': # self-call to public.
mem_pos = sub.args[0].args[-1]
mem_size = get_size_of_type(sub.typ) * 32
return LLLnode.from_list(['return', mem_pos, mem_size],
typ=sub.typ)
elif (sub.annotation and 'Internal Call' in sub.annotation):
mem_pos = sub.args[
-1].value if sub.value == 'seq_unchecked' else sub.args[
0].args[-1]
mem_size = get_size_of_type(sub.typ) * 32
# Add zero padder if bytes are present in output.
zero_padder = ['pass']
byte_arrays = [(i, x) for i, x in enumerate(sub.typ.members)
if isinstance(x, ByteArrayType)]
if byte_arrays:
i, x = byte_arrays[-1]
zero_padder = zero_pad(bytez_placeholder=[
'add', mem_pos, ['mload', mem_pos + i * 32]
],
maxlen=x.maxlen)
return LLLnode.from_list(
['seq'] + [sub] + [zero_padder] +
[self.make_return_stmt(mem_pos, mem_size)],
typ=sub.typ,
pos=getpos(self.stmt),
valency=0)
subs = []
# Pre-allocate loop_memory_position if required for private function returning.
loop_memory_position = self.context.new_placeholder(
typ=BaseType('uint256')) if self.context.is_private else None
# Allocate dynamic off set counter, to keep track of the total packed dynamic data size.
dynamic_offset_counter_placeholder = self.context.new_placeholder(
typ=BaseType('uint256'))
dynamic_offset_counter = LLLnode(
dynamic_offset_counter_placeholder,
typ=None,
annotation=
"dynamic_offset_counter" # dynamic offset position counter.
)
new_sub = LLLnode.from_list(
self.context.new_placeholder(typ=BaseType('uint256')),
typ=self.context.return_type,
location='memory',
annotation='new_sub')
keyz = list(range(len(sub.typ.members)))
dynamic_offset_start = 32 * len(
sub.args) # The static list of args end.
left_token = LLLnode.from_list('_loc',
typ=new_sub.typ,
location="memory")
def get_dynamic_offset_value():
# Get value of dynamic offset counter.
return ['mload', dynamic_offset_counter]
def increment_dynamic_offset(dynamic_spot):
# Increment dyanmic offset counter in memory.
return [
'mstore', dynamic_offset_counter,
[
'add',
['add', ['ceil32', ['mload', dynamic_spot]], 32],
['mload', dynamic_offset_counter]
]
]
for i, typ in enumerate(keyz):
arg = sub.args[i]
variable_offset = LLLnode.from_list(
['add', 32 * i, left_token],
typ=arg.typ,
annotation='variable_offset')
if isinstance(arg.typ, ByteArrayType):
# Store offset pointer value.
subs.append([
'mstore', variable_offset,
get_dynamic_offset_value()
])
# Store dynamic data, from offset pointer onwards.
dynamic_spot = LLLnode.from_list(
['add', left_token,
get_dynamic_offset_value()],
location="memory",
typ=arg.typ,
annotation='dynamic_spot')
subs.append(
make_setter(dynamic_spot,
arg,
location="memory",
pos=getpos(self.stmt)))
subs.append(increment_dynamic_offset(dynamic_spot))
elif isinstance(arg.typ, BaseType):
subs.append(
make_setter(variable_offset,
arg,
"memory",
pos=getpos(self.stmt)))
else:
raise Exception("Can't return type %s as part of tuple",
type(arg.typ))
setter = LLLnode.from_list([
'seq', [
'mstore', dynamic_offset_counter, dynamic_offset_start
], ['with', '_loc', new_sub, ['seq'] + subs]
],
typ=None)
return LLLnode.from_list([
'seq', setter,
self.make_return_stmt(new_sub, get_dynamic_offset_value(),
loop_memory_position)
],
typ=None,
pos=getpos(self.stmt),
valency=0)
else:
raise TypeMismatchException("Can only return base type!",
self.stmt)
def build_in_comparator(self):
left = Expr(self.expr.left, self.context).lll_node
right = Expr(self.expr.right, self.context).lll_node
if left.typ != right.typ.subtype:
raise TypeMismatch(
f"{left.typ} cannot be in a list of {right.typ.subtype}",
self.expr,
)
result_placeholder = self.context.new_placeholder(BaseType('bool'))
setter = []
# Load nth item from list in memory.
if right.value == 'multi':
# Copy literal to memory to be compared.
tmp_list = LLLnode.from_list(obj=self.context.new_placeholder(
ListType(right.typ.subtype, right.typ.count)),
typ=ListType(right.typ.subtype,
right.typ.count),
location='memory')
setter = make_setter(tmp_list,
right,
'memory',
pos=getpos(self.expr))
load_i_from_list = [
'mload',
[
'add', tmp_list,
['mul', 32, ['mload', MemoryPositions.FREE_LOOP_INDEX]]
],
]
elif right.location == "storage":
load_i_from_list = [
'sload',
[
'add', ['sha3_32', right],
['mload', MemoryPositions.FREE_LOOP_INDEX]
],
]
else:
load_i_from_list = [
'mload',
[
'add', right,
['mul', 32, ['mload', MemoryPositions.FREE_LOOP_INDEX]]
],
]
# Condition repeat loop has to break on.
break_loop_condition = [
'if',
['eq', unwrap_location(left), load_i_from_list],
[
'seq',
['mstore', '_result', 1], # store true.
'break'
]
]
# Repeat loop to loop-compare each item in the list.
for_loop_sequence = [['mstore', result_placeholder, 0],
[
'with', '_result', result_placeholder,
[
'repeat',
MemoryPositions.FREE_LOOP_INDEX,
0,
right.typ.count,
break_loop_condition,
]
], ['mload', result_placeholder]]
# Save list to memory, so one can iterate over it,
# used when literal was created with tmp_list.
if setter:
compare_sequence = ['seq', setter] + for_loop_sequence
else:
compare_sequence = ['seq'] + for_loop_sequence
# Compare the result of the repeat loop to 1, to know if a match was found.
o = LLLnode.from_list(['eq', 1, compare_sequence],
typ='bool',
annotation="in comporator")
return o
def parse_return(self):
if self.context.return_type is None:
if self.stmt.value:
raise TypeMismatchException("Not expecting to return a value",
self.stmt)
return LLLnode.from_list(
make_return_stmt(self.stmt, self.context, 0, 0),
typ=None,
pos=getpos(self.stmt),
valency=0,
)
if not self.stmt.value:
raise TypeMismatchException("Expecting to return a value",
self.stmt)
sub = Expr(self.stmt.value, self.context).lll_node
# Returning a value (most common case)
if isinstance(sub.typ, BaseType):
sub = unwrap_location(sub)
if not isinstance(self.context.return_type, BaseType):
raise TypeMismatchException(
f"Return type units mismatch {sub.typ} {self.context.return_type}",
self.stmt.value)
elif self.context.return_type != sub.typ and not sub.typ.is_literal:
raise TypeMismatchException(
f"Trying to return base type {sub.typ}, output expecting "
f"{self.context.return_type}",
self.stmt.value,
)
elif sub.typ.is_literal and (
self.context.return_type.typ == sub.typ
or 'int' in self.context.return_type.typ
and 'int' in sub.typ.typ): # noqa: E501
if not SizeLimits.in_bounds(self.context.return_type.typ,
sub.value):
raise InvalidLiteralException(
"Number out of range: " + str(sub.value), self.stmt)
else:
return LLLnode.from_list(
[
'seq', ['mstore', 0, sub],
make_return_stmt(self.stmt, self.context, 0, 32)
],
typ=None,
pos=getpos(self.stmt),
valency=0,
)
elif is_base_type(sub.typ, self.context.return_type.typ) or (
is_base_type(sub.typ, 'int128') and is_base_type(
self.context.return_type, 'int256')): # noqa: E501
return LLLnode.from_list(
[
'seq', ['mstore', 0, sub],
make_return_stmt(self.stmt, self.context, 0, 32)
],
typ=None,
pos=getpos(self.stmt),
valency=0,
)
else:
raise TypeMismatchException(
f"Unsupported type conversion: {sub.typ} to {self.context.return_type}",
self.stmt.value,
)
# Returning a byte array
elif isinstance(sub.typ, ByteArrayLike):
if not sub.typ.eq_base(self.context.return_type):
raise TypeMismatchException(
f"Trying to return base type {sub.typ}, output expecting "
f"{self.context.return_type}",
self.stmt.value,
)
if sub.typ.maxlen > self.context.return_type.maxlen:
raise TypeMismatchException(
f"Cannot cast from greater max-length {sub.typ.maxlen} to shorter "
f"max-length {self.context.return_type.maxlen}",
self.stmt.value,
)
# loop memory has to be allocated first.
loop_memory_position = self.context.new_placeholder(
typ=BaseType('uint256'))
# len & bytez placeholder have to be declared after each other at all times.
len_placeholder = self.context.new_placeholder(
typ=BaseType('uint256'))
bytez_placeholder = self.context.new_placeholder(typ=sub.typ)
if sub.location in ('storage', 'memory'):
return LLLnode.from_list([
'seq',
make_byte_array_copier(LLLnode(
bytez_placeholder, location='memory', typ=sub.typ),
sub,
pos=getpos(self.stmt)),
zero_pad(bytez_placeholder),
['mstore', len_placeholder, 32],
make_return_stmt(
self.stmt,
self.context,
len_placeholder,
['ceil32', ['add', ['mload', bytez_placeholder], 64]],
loop_memory_position=loop_memory_position,
)
],
typ=None,
pos=getpos(self.stmt),
valency=0)
else:
raise Exception(f"Invalid location: {sub.location}")
elif isinstance(sub.typ, ListType):
sub_base_type = re.split(r'\(|\[', str(sub.typ.subtype))[0]
ret_base_type = re.split(r'\(|\[',
str(self.context.return_type.subtype))[0]
loop_memory_position = self.context.new_placeholder(
typ=BaseType('uint256'))
if sub_base_type != ret_base_type:
raise TypeMismatchException(
f"List return type {sub_base_type} does not match specified "
f"return type, expecting {ret_base_type}", self.stmt)
elif sub.location == "memory" and sub.value != "multi":
return LLLnode.from_list(
make_return_stmt(
self.stmt,
self.context,
sub,
get_size_of_type(self.context.return_type) * 32,
loop_memory_position=loop_memory_position,
),
typ=None,
pos=getpos(self.stmt),
valency=0,
)
else:
new_sub = LLLnode.from_list(
self.context.new_placeholder(self.context.return_type),
typ=self.context.return_type,
location='memory',
)
setter = make_setter(new_sub,
sub,
'memory',
pos=getpos(self.stmt))
return LLLnode.from_list([
'seq', setter,
make_return_stmt(
self.stmt,
self.context,
new_sub,
get_size_of_type(self.context.return_type) * 32,
loop_memory_position=loop_memory_position,
)
],
typ=None,
pos=getpos(self.stmt))
# Returning a struct
elif isinstance(sub.typ, StructType):
retty = self.context.return_type
if not isinstance(retty, StructType) or retty.name != sub.typ.name:
raise TypeMismatchException(
f"Trying to return {sub.typ}, output expecting {self.context.return_type}",
self.stmt.value,
)
return gen_tuple_return(self.stmt, self.context, sub)
# Returning a tuple.
elif isinstance(sub.typ, TupleType):
if not isinstance(self.context.return_type, TupleType):
raise TypeMismatchException(
f"Trying to return tuple type {sub.typ}, output expecting "
f"{self.context.return_type}",
self.stmt.value,
)
if len(self.context.return_type.members) != len(sub.typ.members):
raise StructureException("Tuple lengths don't match!",
self.stmt)
# check return type matches, sub type.
for i, ret_x in enumerate(self.context.return_type.members):
s_member = sub.typ.members[i]
sub_type = s_member if isinstance(s_member,
NodeType) else s_member.typ
if type(sub_type) is not type(ret_x):
raise StructureException(
"Tuple return type does not match annotated return. "
f"{type(sub_type)} != {type(ret_x)}", self.stmt)
return gen_tuple_return(self.stmt, self.context, sub)
else:
raise TypeMismatchException(f"Can't return type {sub.typ}",
self.stmt)
def parse_for_list(self):
with self.context.range_scope():
iter_list_node = Expr(self.stmt.iter, self.context).lll_node
if not isinstance(iter_list_node.typ.subtype,
BaseType): # Sanity check on list subtype.
raise StructureException(
'For loops allowed only on basetype lists.', self.stmt.iter)
iter_var_type = (self.context.vars.get(self.stmt.iter.id).typ
if isinstance(self.stmt.iter, ast.Name) else None)
subtype = iter_list_node.typ.subtype.typ
varname = self.stmt.target.id
value_pos = self.context.new_variable(
varname,
BaseType(subtype, unit=iter_list_node.typ.subtype.unit),
)
i_pos_raw_name = '_index_for_' + varname
i_pos = self.context.new_internal_variable(
i_pos_raw_name,
BaseType(subtype),
)
self.context.forvars[varname] = True
# Is a list that is already allocated to memory.
if iter_var_type:
list_name = self.stmt.iter.id
# make sure list cannot be altered whilst iterating.
with self.context.in_for_loop_scope(list_name):
iter_var = self.context.vars.get(self.stmt.iter.id)
if iter_var.location == 'calldata':
fetcher = 'calldataload'
elif iter_var.location == 'memory':
fetcher = 'mload'
else:
raise CompilerPanic(
'List iteration only supported on in-memory types',
self.expr)
body = [
'seq',
[
'mstore',
value_pos,
[
fetcher,
[
'add', iter_var.pos,
['mul', ['mload', i_pos], 32]
]
],
],
parse_body(self.stmt.body, self.context)
]
o = LLLnode.from_list(
['repeat', i_pos, 0, iter_var.size, body],
typ=None,
pos=getpos(self.stmt))
# List gets defined in the for statement.
elif isinstance(self.stmt.iter, ast.List):
# Allocate list to memory.
count = iter_list_node.typ.count
tmp_list = LLLnode.from_list(obj=self.context.new_placeholder(
ListType(iter_list_node.typ.subtype, count)),
typ=ListType(
iter_list_node.typ.subtype,
count),
location='memory')
setter = make_setter(tmp_list,
iter_list_node,
'memory',
pos=getpos(self.stmt))
body = [
'seq',
[
'mstore', value_pos,
[
'mload',
['add', tmp_list, ['mul', ['mload', i_pos], 32]]
]
],
parse_body(self.stmt.body, self.context)
]
o = LLLnode.from_list(
['seq', setter, ['repeat', i_pos, 0, count, body]],
typ=None,
pos=getpos(self.stmt))
# List contained in storage.
elif isinstance(self.stmt.iter, ast.Attribute):
count = iter_list_node.typ.count
list_name = iter_list_node.annotation
# make sure list cannot be altered whilst iterating.
with self.context.in_for_loop_scope(list_name):
body = [
'seq',
[
'mstore', value_pos,
[
'sload',
[
'add', ['sha3_32', iter_list_node],
['mload', i_pos]
]
]
],
parse_body(self.stmt.body, self.context),
]
o = LLLnode.from_list(
['seq', ['repeat', i_pos, 0, count, body]],
typ=None,
pos=getpos(self.stmt))
del self.context.vars[varname]
# this kind of open access to the vars dict should be disallowed.
# we should use member functions to provide an API for these kinds
# of operations.
del self.context.vars[self.context._mangle(i_pos_raw_name)]
del self.context.forvars[varname]
return o
def parse_Return(self):
if self.context.return_type is None:
if self.stmt.value:
return
return LLLnode.from_list(
make_return_stmt(self.stmt, self.context, 0, 0),
typ=None,
pos=getpos(self.stmt),
valency=0,
)
sub = Expr(self.stmt.value, self.context).lll_node
# Returning a value (most common case)
if isinstance(sub.typ, BaseType):
sub = unwrap_location(sub)
if self.context.return_type != sub.typ and not sub.typ.is_literal:
return
elif sub.typ.is_literal and (
self.context.return_type.typ == sub.typ
or "int" in self.context.return_type.typ
and "int" in sub.typ.typ): # noqa: E501
if SizeLimits.in_bounds(self.context.return_type.typ,
sub.value):
return LLLnode.from_list(
[
"seq",
["mstore", 0, sub],
make_return_stmt(self.stmt, self.context, 0, 32),
],
typ=None,
pos=getpos(self.stmt),
valency=0,
)
elif is_base_type(sub.typ, self.context.return_type.typ) or (
is_base_type(sub.typ, "int128") and is_base_type(
self.context.return_type, "int256")): # noqa: E501
return LLLnode.from_list(
[
"seq", ["mstore", 0, sub],
make_return_stmt(self.stmt, self.context, 0, 32)
],
typ=None,
pos=getpos(self.stmt),
valency=0,
)
return
# Returning a byte array
elif isinstance(sub.typ, ByteArrayLike):
if not sub.typ.eq_base(self.context.return_type):
return
if sub.typ.maxlen > self.context.return_type.maxlen:
return
# loop memory has to be allocated first.
loop_memory_position = self.context.new_placeholder(
typ=BaseType("uint256"))
# len & bytez placeholder have to be declared after each other at all times.
len_placeholder = self.context.new_placeholder(
typ=BaseType("uint256"))
bytez_placeholder = self.context.new_placeholder(typ=sub.typ)
if sub.location in ("storage", "memory"):
return LLLnode.from_list(
[
"seq",
make_byte_array_copier(
LLLnode(bytez_placeholder,
location="memory",
typ=sub.typ),
sub,
pos=getpos(self.stmt),
),
zero_pad(bytez_placeholder),
["mstore", len_placeholder, 32],
make_return_stmt(
self.stmt,
self.context,
len_placeholder,
[
"ceil32",
["add", ["mload", bytez_placeholder], 64]
],
loop_memory_position=loop_memory_position,
),
],
typ=None,
pos=getpos(self.stmt),
valency=0,
)
return
elif isinstance(sub.typ, ListType):
loop_memory_position = self.context.new_placeholder(
typ=BaseType("uint256"))
if sub.typ != self.context.return_type:
return
elif sub.location == "memory" and sub.value != "multi":
return LLLnode.from_list(
make_return_stmt(
self.stmt,
self.context,
sub,
get_size_of_type(self.context.return_type) * 32,
loop_memory_position=loop_memory_position,
),
typ=None,
pos=getpos(self.stmt),
valency=0,
)
else:
new_sub = LLLnode.from_list(
self.context.new_placeholder(self.context.return_type),
typ=self.context.return_type,
location="memory",
)
setter = make_setter(new_sub,
sub,
"memory",
pos=getpos(self.stmt))
return LLLnode.from_list(
[
"seq",
setter,
make_return_stmt(
self.stmt,
self.context,
new_sub,
get_size_of_type(self.context.return_type) * 32,
loop_memory_position=loop_memory_position,
),
],
typ=None,
pos=getpos(self.stmt),
)
# Returning a struct
elif isinstance(sub.typ, StructType):
retty = self.context.return_type
if isinstance(retty, StructType) and retty.name == sub.typ.name:
return gen_tuple_return(self.stmt, self.context, sub)
# Returning a tuple.
elif isinstance(sub.typ, TupleType):
if not isinstance(self.context.return_type, TupleType):
return
if len(self.context.return_type.members) != len(sub.typ.members):
return
# check return type matches, sub type.
for i, ret_x in enumerate(self.context.return_type.members):
s_member = sub.typ.members[i]
sub_type = s_member if isinstance(s_member,
NodeType) else s_member.typ
if type(sub_type) is not type(ret_x):
return
return gen_tuple_return(self.stmt, self.context, sub)
def pack_logging_data(expected_data, args, context, pos):
# Checks to see if there's any data
if not args:
return ['seq'], 0, None, 0
holder = ['seq']
maxlen = len(args) * 32 # total size of all packed args (upper limit)
# Unroll any function calls, to temp variables.
prealloacted = {}
for idx, (arg, _expected_arg) in enumerate(zip(args, expected_data)):
if isinstance(arg, (ast.Str, ast.Call)):
expr = Expr(arg, context)
source_lll = expr.lll_node
typ = source_lll.typ
if isinstance(arg, ast.Str):
if len(arg.s) > typ.maxlen:
raise TypeMismatchException(
"Data input bytes are to big: %r %r" %
(len(arg.s), typ), pos)
tmp_variable = context.new_variable(
'_log_pack_var_%i_%i' % (arg.lineno, arg.col_offset),
source_lll.typ,
)
tmp_variable_node = LLLnode.from_list(
tmp_variable,
typ=source_lll.typ,
pos=getpos(arg),
location="memory",
annotation='log_prealloacted %r' % source_lll.typ,
)
# Store len.
# holder.append(['mstore', len_placeholder, ['mload', unwrap_location(source_lll)]])
# Copy bytes.
holder.append(
make_setter(tmp_variable_node,
source_lll,
pos=getpos(arg),
location='memory'))
prealloacted[idx] = tmp_variable_node
requires_dynamic_offset = any(
[isinstance(data.typ, ByteArrayLike) for data in expected_data])
if requires_dynamic_offset:
# Iterator used to zero pad memory.
zero_pad_i = context.new_placeholder(BaseType('uint256'))
dynamic_offset_counter = context.new_placeholder(BaseType(32))
dynamic_placeholder = context.new_placeholder(BaseType(32))
else:
dynamic_offset_counter = None
zero_pad_i = None
# Create placeholder for static args. Note: order of new_*() is important.
placeholder_map = {}
for i, (_arg, data) in enumerate(zip(args, expected_data)):
typ = data.typ
if not isinstance(typ, ByteArrayLike):
placeholder = context.new_placeholder(typ)
else:
placeholder = context.new_placeholder(BaseType(32))
placeholder_map[i] = placeholder
# Populate static placeholders.
for i, (arg, data) in enumerate(zip(args, expected_data)):
typ = data.typ
placeholder = placeholder_map[i]
if not isinstance(typ, ByteArrayLike):
holder, maxlen = pack_args_by_32(
holder,
maxlen,
prealloacted.get(i, arg),
typ,
context,
placeholder,
zero_pad_i=zero_pad_i,
pos=pos,
)
# Dynamic position starts right after the static args.
if requires_dynamic_offset:
holder.append(
LLLnode.from_list(['mstore', dynamic_offset_counter, maxlen]))
# Calculate maximum dynamic offset placeholders, used for gas estimation.
for _arg, data in zip(args, expected_data):
typ = data.typ
if isinstance(typ, ByteArrayLike):
maxlen += 32 + ceil32(typ.maxlen)
if requires_dynamic_offset:
datamem_start = dynamic_placeholder + 32
else:
datamem_start = placeholder_map[0]
# Copy necessary data into allocated dynamic section.
for i, (arg, data) in enumerate(zip(args, expected_data)):
typ = data.typ
if isinstance(typ, ByteArrayLike):
pack_args_by_32(holder=holder,
maxlen=maxlen,
arg=prealloacted.get(i, arg),
typ=typ,
context=context,
placeholder=placeholder_map[i],
datamem_start=datamem_start,
dynamic_offset_counter=dynamic_offset_counter,
zero_pad_i=zero_pad_i,
pos=pos)
return holder, maxlen, dynamic_offset_counter, datamem_start
def gen_tuple_return(stmt, context, sub):
abi_typ = abi_type_of(context.return_type)
# according to the ABI, return types are ALWAYS tuples even if
# only one element is being returned.
# https://solidity.readthedocs.io/en/latest/abi-spec.html#function-selector-and-argument-encoding
# "and the return values v_1, ..., v_k of f are encoded as
#
# enc((v_1, ..., v_k))
# i.e. the values are combined into a tuple and encoded.
# "
# therefore, wrap it in a tuple if it's not already a tuple.
# (big difference between returning `(bytes,)` and `bytes`.
abi_typ = ensure_tuple(abi_typ)
abi_bytes_needed = abi_typ.static_size() + abi_typ.dynamic_size_bound()
dst = context.memory_allocator.expand_memory(abi_bytes_needed)
return_buffer = LLLnode(dst,
location="memory",
annotation="return_buffer",
typ=context.return_type)
check_assign(return_buffer, sub, pos=getpos(stmt))
if sub.value == "multi":
if isinstance(context.return_type,
TupleType) and not abi_typ.dynamic_size_bound():
# for tuples where every value is of the same type and a fixed length,
# we can simplify the encoding by treating it as though it were an array
base_types = set()
for typ in context.return_type.members:
while isinstance(typ, ListType):
typ = typ.subtype
base_types.add(typ.typ)
if len(base_types) == 1:
new_sub = LLLnode.from_list(
context.new_internal_variable(context.return_type),
typ=context.return_type,
location="memory",
)
setter = make_setter(new_sub, sub, "memory", pos=getpos(stmt))
return LLLnode.from_list(
[
"seq",
setter,
make_return_stmt(
stmt,
context,
new_sub,
get_size_of_type(context.return_type) * 32,
),
],
typ=None,
pos=getpos(stmt),
)
# in case of multi we can't create a variable to store location of the return expression
# as multi can have data from multiple location like store, calldata etc
encode_out = abi_encode(return_buffer,
sub,
pos=getpos(stmt),
returns=True)
load_return_len = ["mload", MemoryPositions.FREE_VAR_SPACE]
os = [
"seq",
["mstore", MemoryPositions.FREE_VAR_SPACE, encode_out],
make_return_stmt(stmt, context, return_buffer, load_return_len),
]
return LLLnode.from_list(os, typ=None, pos=getpos(stmt), valency=0)
# for tuple return types where a function is called inside the tuple, we
# process the calls prior to encoding the return data
if sub.value == "seq_unchecked" and sub.args[-1].value == "multi":
encode_out = abi_encode(return_buffer,
sub.args[-1],
pos=getpos(stmt),
returns=True)
load_return_len = ["mload", MemoryPositions.FREE_VAR_SPACE]
os = (["seq"] + sub.args[:-1] + [
["mstore", MemoryPositions.FREE_VAR_SPACE, encode_out],
make_return_stmt(stmt, context, return_buffer, load_return_len),
])
return LLLnode.from_list(os, typ=None, pos=getpos(stmt), valency=0)
# for all othe cases we are creating a stack variable named sub_loc to store the location
# of the return expression. This is done so that the return expression does not get evaluated
# abi-encode uses a function named o_list which evaluate the expression multiple times
sub_loc = LLLnode("sub_loc", typ=sub.typ, location=sub.location)
encode_out = abi_encode(return_buffer,
sub_loc,
pos=getpos(stmt),
returns=True)
load_return_len = ["mload", MemoryPositions.FREE_VAR_SPACE]
os = [
"with",
"sub_loc",
sub,
[
"seq",
["mstore", MemoryPositions.FREE_VAR_SPACE, encode_out],
make_return_stmt(stmt, context, return_buffer, load_return_len),
],
]
return LLLnode.from_list(os, typ=None, pos=getpos(stmt), valency=0)
