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_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)
