def as_unitless_number(expr, args, kwargs, context):
return LLLnode(value=args[0].value,
args=args[0].args,
typ=BaseType(args[0].typ.typ, {}),
pos=getpos(expr))
def bitwise_or(expr, args, kwargs, context):
return LLLnode.from_list(['or', args[0], args[1]],
typ=BaseType('uint256'),
pos=getpos(expr))
def concat(expr, context):
args = [Expr(arg, context).lll_node for arg in expr.args]
if len(args) < 2:
raise StructureException("Concat expects at least two arguments", expr)
for expr_arg, arg in zip(expr.args, args):
if not isinstance(arg.typ, ByteArrayType) and not is_base_type(
arg.typ, 'bytes32'):
raise TypeMismatchException(
"Concat expects byte arrays or bytes32 objects", expr_arg)
# Maximum length of the output
total_maxlen = sum([
arg.typ.maxlen if isinstance(arg.typ, ByteArrayType) else 32
for arg in args
])
# Node representing the position of the output in memory
placeholder = context.new_placeholder(ByteArrayType(total_maxlen))
# Object representing the output
seq = []
# For each argument we are concatenating...
for arg in args:
# Start pasting into a position the starts at zero, and keeps
# incrementing as we concatenate arguments
placeholder_node = LLLnode.from_list(['add', placeholder, '_poz'],
typ=ByteArrayType(total_maxlen),
location='memory')
placeholder_node_plus_32 = LLLnode.from_list(
['add', ['add', placeholder, '_poz'], 32],
typ=ByteArrayType(total_maxlen),
location='memory')
if isinstance(arg.typ, ByteArrayType):
# Ignore empty strings
if arg.typ.maxlen == 0:
continue
# Get the length of the current argument
if arg.location == "memory":
length = LLLnode.from_list(['mload', '_arg'],
typ=BaseType('int128'))
argstart = LLLnode.from_list(['add', '_arg', 32],
typ=arg.typ,
location=arg.location)
elif arg.location == "storage":
length = LLLnode.from_list(['sload', ['sha3_32', '_arg']],
typ=BaseType('int128'))
argstart = LLLnode.from_list(['add', ['sha3_32', '_arg'], 1],
typ=arg.typ,
location=arg.location)
# Make a copier to copy over data from that argyument
seq.append([
'with',
'_arg',
arg,
[
'seq',
make_byte_slice_copier(placeholder_node_plus_32,
argstart,
length,
arg.typ.maxlen,
pos=getpos(expr)),
# Change the position to start at the correct
# place to paste the next value
['set', '_poz', ['add', '_poz', length]]
]
])
else:
seq.append([
'seq',
[
'mstore', ['add', placeholder_node, 32],
unwrap_location(arg)
], ['set', '_poz', ['add', '_poz', 32]]
])
# The position, after all arguments are processing, equals the total
# length. Paste this in to make the output a proper bytearray
seq.append(['mstore', placeholder, '_poz'])
# Memory location of the output
seq.append(placeholder)
return LLLnode.from_list(['with', '_poz', 0, ['seq'] + seq],
typ=ByteArrayType(total_maxlen),
location='memory',
pos=getpos(expr),
annotation='concat')
def extract32(expr, args, kwargs, context):
sub, index = args
ret_type = kwargs['type']
# Get length and specific element
if sub.location == "memory":
lengetter = LLLnode.from_list(['mload', '_sub'],
typ=BaseType('int128'))
elementgetter = lambda index: LLLnode.from_list(
['mload', ['add', '_sub', ['add', 32, ['mul', 32, index]]]],
typ=BaseType('int128'))
elif sub.location == "storage":
lengetter = LLLnode.from_list(['sload', ['sha3_32', '_sub']],
typ=BaseType('int128'))
elementgetter = lambda index: LLLnode.from_list(
['sload', ['add', ['sha3_32', '_sub'], ['add', 1, index]]],
typ=BaseType('int128'))
# Special case: index known to be a multiple of 32
if isinstance(index.value, int) and not index.value % 32:
o = LLLnode.from_list([
'with', '_sub', sub,
elementgetter(
['div', ['clamp', 0, index, ['sub', lengetter, 32]], 32])
],
typ=BaseType(ret_type),
annotation='extracting 32 bytes')
# General case
else:
o = LLLnode.from_list([
'with', '_sub', sub,
[
'with', '_len', lengetter,
[
'with', '_index', ['clamp', 0, index, ['sub', '_len', 32]],
[
'with', '_mi32', ['mod', '_index', 32],
[
'with', '_di32', ['div', '_index', 32],
[
'if', '_mi32',
[
'add',
[
'mul',
elementgetter('_di32'),
['exp', 256, '_mi32']
],
[
'div',
elementgetter(['add', '_di32', 1]),
['exp', 256, ['sub', 32, '_mi32']]
]
],
elementgetter('_di32')
]
]
]
]
]
],
typ=BaseType(ret_type),
pos=getpos(expr),
annotation='extracting 32 bytes')
if ret_type == 'int128':
return LLLnode.from_list([
'clamp', ['mload', MemoryPositions.MINNUM], o,
['mload', MemoryPositions.MAXNUM]
],
typ=BaseType('int128'),
pos=getpos(expr))
elif ret_type == 'address':
return LLLnode.from_list(
['uclamplt', o, ['mload', MemoryPositions.ADDRSIZE]],
typ=BaseType(ret_type),
pos=getpos(expr))
else:
return o
def add_variable_offset(parent, key, pos):
typ, location = parent.typ, parent.location
if isinstance(typ, (StructType, TupleType)):
if isinstance(typ, StructType):
if not isinstance(key, str):
raise TypeMismatchException(
"Expecting a member variable access; cannot access element %r"
% key, pos)
if key not in typ.members:
raise TypeMismatchException(
"Object does not have member variable %s" % key, pos)
subtype = typ.members[key]
attrs = sorted(typ.members.keys())
if key not in attrs:
raise TypeMismatchException(
"Member %s not found. Only the following available: %s" %
(key, " ".join(attrs)), pos)
index = attrs.index(key)
annotation = key
else:
if not isinstance(key, int):
raise TypeMismatchException(
"Expecting a static index; cannot access element %r" % key,
pos)
attrs = list(range(len(typ.members)))
index = key
annotation = None
if location == 'storage':
return LLLnode.from_list([
'add', ['sha3_32', parent],
LLLnode.from_list(index, annotation=annotation)
],
typ=subtype,
location='storage')
elif location == 'storage_prehashed':
return LLLnode.from_list([
'add', parent,
LLLnode.from_list(index, annotation=annotation)
],
typ=subtype,
location='storage')
elif location == 'memory':
offset = 0
for i in range(index):
offset += 32 * get_size_of_type(typ.members[attrs[i]])
return LLLnode.from_list(['add', offset, parent],
typ=typ.members[key],
location='memory',
annotation=annotation)
else:
raise TypeMismatchException(
"Not expecting a member variable access")
elif isinstance(typ, MappingType):
if isinstance(key.typ, ByteArrayType):
if not isinstance(typ.keytype, ByteArrayType) or (
typ.keytype.maxlen < key.typ.maxlen):
raise TypeMismatchException(
'Mapping keys of bytes cannot be cast, use exact same bytes type of: %s'
% str(typ.keytype), pos)
subtype = typ.valuetype
if len(key.args[0].args) >= 3: # handle bytes literal.
sub = LLLnode.from_list([
'seq', key,
[
'sha3', ['add', key.args[0].args[-1], 32],
['mload', key.args[0].args[-1]]
]
])
else:
sub = LLLnode.from_list([
'sha3', ['add', key.args[0].value, 32],
['mload', key.args[0].value]
])
else:
subtype = typ.valuetype
sub = base_type_conversion(key, key.typ, typ.keytype, pos=pos)
if location == 'storage':
return LLLnode.from_list(['sha3_64', parent, sub],
typ=subtype,
location='storage')
elif location == 'memory':
raise TypeMismatchException(
"Can only have fixed-side arrays in memory, not mappings", pos)
elif isinstance(typ, ListType):
subtype = typ.subtype
sub = [
'uclamplt',
base_type_conversion(key, key.typ, BaseType('int128'), pos=pos),
typ.count
]
if location == 'storage':
return LLLnode.from_list(['add', ['sha3_32', parent], sub],
typ=subtype,
location='storage')
elif location == 'storage_prehashed':
return LLLnode.from_list(['add', parent, sub],
typ=subtype,
location='storage')
elif location == 'memory':
offset = 32 * get_size_of_type(subtype)
return LLLnode.from_list(['add', ['mul', offset, sub], parent],
typ=subtype,
location='memory')
else:
raise TypeMismatchException("Not expecting an array access ", pos)
else:
raise TypeMismatchException(
"Cannot access the child of a constant variable! %r" % typ, pos)
if args[0].value <= 0:
raise InvalidLiteralException("Negative wei value not allowed",
expr)
sub = ['mul', args[0].value, denomination]
elif args[0].typ.typ == 'uint256':
sub = ['mul', args[0], denomination]
else:
sub = ['div', ['mul', args[0], denomination], DECIMAL_DIVISOR]
return LLLnode.from_list(sub,
typ=BaseType('uint256', {'wei': 1}),
location=None,
pos=getpos(expr))
zero_value = LLLnode.from_list(0, typ=BaseType('uint256', {'wei': 1}))
false_value = LLLnode.from_list(0, typ=BaseType('bool', is_literal=True))
@signature('address',
'bytes',
outsize='num_literal',
gas='uint256',
value=Optional('uint256', zero_value),
delegate_call=Optional('bool', false_value))
def raw_call(expr, args, kwargs, context):
to, data = args
gas, value, outsize, delegate_call = kwargs['gas'], kwargs[
'value'], kwargs['outsize'], kwargs['delegate_call']
if delegate_call.typ.is_literal is False:
raise TypeMismatchException(
def pack_args_by_32(holder,
maxlen,
arg,
typ,
context,
placeholder,
dynamic_offset_counter=None,
datamem_start=None,
zero_pad_i=None,
pos=None):
"""
Copy necessary variables to pre-allocated memory section.
:param holder: Complete holder for all args
:param maxlen: Total length in bytes of the full arg section (static + dynamic).
:param arg: Current arg to pack
:param context: Context of arg
:param placeholder: Static placeholder for static argument part.
:param dynamic_offset_counter: position counter stored in static args.
:param dynamic_placeholder: pointer to current position in memory to write dynamic values to.
:param datamem_start: position where the whole datemem section starts.
"""
if isinstance(typ, BaseType):
value = parse_expr(arg, context)
value = base_type_conversion(value, value.typ, typ, pos)
holder.append(
LLLnode.from_list(['mstore', placeholder, value],
typ=typ,
location='memory'))
elif isinstance(typ, ByteArrayType):
bytez = b''
source_expr = Expr(arg, context)
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)
for c in arg.s:
if ord(c) >= 256:
raise InvalidLiteralException(
"Cannot insert special character %r into byte array" %
c, pos)
bytez += bytes([ord(c)])
holder.append(source_expr.lll_node)
# Set static offset, in arg slot.
holder.append(
LLLnode.from_list(
['mstore', placeholder, ['mload', dynamic_offset_counter]]))
# Get the biginning to write the ByteArray to.
dest_placeholder = LLLnode.from_list(
['add', datamem_start, ['mload', dynamic_offset_counter]],
typ=typ,
location='memory',
annotation="pack_args_by_32:dest_placeholder")
copier = make_byte_array_copier(dest_placeholder,
source_expr.lll_node,
pos=pos)
holder.append(copier)
# Add zero padding.
new_maxlen = ceil32(source_expr.lll_node.typ.maxlen)
holder.append([
'with',
'_bytearray_loc',
dest_placeholder,
[
'seq',
[
'repeat',
zero_pad_i,
['mload', '_bytearray_loc'],
new_maxlen,
[
'seq',
[
'if', ['ge', ['mload', zero_pad_i], new_maxlen],
'break'
], # stay within allocated bounds
[
'mstore8',
[
'add', ['add', '_bytearray_loc', 32],
['mload', zero_pad_i]
], 0
]
]
]
]
])
# Increment offset counter.
increment_counter = LLLnode.from_list([
'mstore', dynamic_offset_counter,
[
'add',
[
'add', ['mload', dynamic_offset_counter],
['ceil32', ['mload', dest_placeholder]]
], 32
]
])
holder.append(increment_counter)
elif isinstance(typ, ListType):
maxlen += (typ.count - 1) * 32
typ = typ.subtype
def check_list_type_match(provided): # Check list types match.
if provided != typ:
raise TypeMismatchException(
"Log list type '%s' does not match provided, expected '%s'"
% (provided, typ))
# List from storage
if isinstance(arg, ast.Attribute) and arg.value.id == 'self':
stor_list = context.globals[arg.attr]
check_list_type_match(stor_list.typ.subtype)
size = stor_list.typ.count
for offset in range(0, size):
arg2 = LLLnode.from_list([
'sload',
['add', ['sha3_32', Expr(arg, context).lll_node], offset]
],
typ=typ)
p_holder = context.new_placeholder(
BaseType(32)) if offset > 0 else placeholder
holder, maxlen = pack_args_by_32(holder,
maxlen,
arg2,
typ,
context,
p_holder,
pos=pos)
# List from variable.
elif isinstance(arg, ast.Name):
size = context.vars[arg.id].size
pos = context.vars[arg.id].pos
check_list_type_match(context.vars[arg.id].typ.subtype)
for i in range(0, size):
offset = 32 * i
arg2 = LLLnode.from_list(pos + offset,
typ=typ,
location='memory')
p_holder = context.new_placeholder(
BaseType(32)) if i > 0 else placeholder
holder, maxlen = pack_args_by_32(holder,
maxlen,
arg2,
typ,
context,
p_holder,
pos=pos)
# is list literal.
else:
holder, maxlen = pack_args_by_32(holder,
maxlen,
arg.elts[0],
typ,
context,
placeholder,
pos=pos)
for j, arg2 in enumerate(arg.elts[1:]):
holder, maxlen = pack_args_by_32(holder,
maxlen,
arg2,
typ,
context,
context.new_placeholder(
BaseType(32)),
pos=pos)
return holder, maxlen
def get_length(arg):
if arg.location == "memory":
return LLLnode.from_list(['mload', arg], typ=BaseType('int128'))
elif arg.location == "storage":
return LLLnode.from_list(['sload', ['sha3_32', arg]],
typ=BaseType('int128'))
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)
requires_dynamic_offset = any(
[isinstance(data.typ, ByteArrayType) for data in expected_data])
if requires_dynamic_offset:
zero_pad_i = context.new_placeholder(
BaseType('uint256')) # Iterator used to zero pad memory.
dynamic_offset_counter = context.new_placeholder(BaseType(32))
dynamic_placeholder = context.new_placeholder(BaseType(32))
else:
dynamic_offset_counter = None
zero_pad_i = None
# Populate static placeholders.
placeholder_map = {}
for i, (arg, data) in enumerate(zip(args, expected_data)):
typ = data.typ
placeholder = context.new_placeholder(BaseType(32))
placeholder_map[i] = placeholder
if not isinstance(typ, ByteArrayType):
holder, maxlen = pack_args_by_32(holder,
maxlen,
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 i, (arg, data) in enumerate(zip(args, expected_data)):
typ = data.typ
if isinstance(typ, ByteArrayType):
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, ByteArrayType):
pack_args_by_32(holder=holder,
maxlen=maxlen,
arg=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 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)
# 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)
# Create a local (per function) context.
context = Context(vars=_vars,
global_ctx=global_ctx,
sigs=sigs,
return_type=sig.output_type,
is_constant=sig.const,
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, ByteArrayType) else
get_size_of_type(arg.typ) * 32 for arg in sig.args
])
base_copy_size = sum([
32 if isinstance(arg.typ, ByteArrayType) 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, ByteArrayType):
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, ByteArrayType)
]
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(
['seq_unchecked'] + unpackers + [
0
], # [0] to complete full overarching 'seq' statement, see private_label.
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._custom_units)
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,
ByteArrayType) 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, ByteArrayType):
_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, ByteArrayType):
_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,
LLLnode.from_list(
['mstore', context.callback_ptr, 'pass'],
annotation='pop callback pointer',
pos=getpos(code)) if sig.private else ['pass'],
['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'] + _clampers +
[parse_body(c, context)
for c in code.body] + 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] + clampers +
[parse_body(c, context) for c in code.body] + 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 call_self_private(stmt_expr, context, sig):
# ** Private Call **
# Steps:
# (x) push current local variables
# (x) push arguments
# (x) push jumpdest (callback ptr)
# (x) jump to label
# (x) pop return values
# (x) pop local variables
method_name, expr_args, sig = call_lookup_specs(stmt_expr, context)
pre_init = []
pop_local_vars = []
push_local_vars = []
pop_return_values = []
push_args = []
# Push local variables.
if context.vars:
var_slots = [(v.pos, v.size) for name, v in context.vars.items()]
var_slots.sort(key=lambda x: x[0])
mem_from, mem_to = var_slots[0][
0], var_slots[-1][0] + var_slots[-1][1] * 32
push_local_vars = [['mload', pos]
for pos in range(mem_from, mem_to, 32)]
pop_local_vars = [['mstore', pos, 'pass']
for pos in reversed(range(mem_from, mem_to, 32))]
# Push Arguments
if expr_args:
inargs, inargsize, arg_pos = pack_arguments(sig,
expr_args,
context,
return_placeholder=False,
pos=getpos(stmt_expr))
push_args += [
inargs
] # copy arguments first, to not mess up the push/pop sequencing.
static_arg_count = len(expr_args) * 32
static_pos = arg_pos + static_arg_count
total_arg_size = ceil32(inargsize - 4)
if len(expr_args) * 32 != total_arg_size: # requires dynamic section.
ident = 'push_args_%d_%d_%d' % (sig.method_id, stmt_expr.lineno,
stmt_expr.col_offset)
start_label = ident + '_start'
end_label = ident + '_end'
i_placeholder = context.new_placeholder(BaseType('uint256'))
push_args += [
['mstore', i_placeholder, arg_pos + total_arg_size],
['label', start_label],
[
'if', ['lt', ['mload', i_placeholder], static_pos],
['goto', end_label]
],
[
'if_unchecked',
['ne', ['mload', ['mload', i_placeholder]], 0],
['mload', ['mload', i_placeholder]]
],
[
'mstore', i_placeholder,
['sub', ['mload', i_placeholder], 32]
], # decrease i
['goto', start_label],
['label', end_label]
]
# push static section
push_args += [['mload', pos]
for pos in reversed(range(arg_pos, static_pos, 32))]
# Jump to function label.
jump_to_func = [
['add', ['pc'], 6], # set callback pointer.
['goto', 'priv_{}'.format(sig.method_id)],
['jumpdest'],
]
# Pop return values.
returner = [0]
if sig.output_type:
output_placeholder, returner, output_size = call_make_placeholder(
stmt_expr, context, sig)
if output_size > 0:
dynamic_offsets = []
if isinstance(sig.output_type, (BaseType, ListType)):
pop_return_values = [[
'mstore', ['add', output_placeholder, pos], 'pass'
] for pos in range(0, output_size, 32)]
elif isinstance(sig.output_type, ByteArrayType):
dynamic_offsets = [(0, sig.output_type)]
pop_return_values = [
['pop', 'pass'],
]
elif isinstance(sig.output_type, TupleType):
static_offset = 0
pop_return_values = []
for out_type in sig.output_type.members:
if isinstance(out_type, ByteArrayType):
pop_return_values.append([
'mstore',
['add', output_placeholder, static_offset], 'pass'
])
dynamic_offsets.append(([
'mload',
['add', output_placeholder, static_offset]
], out_type))
else:
pop_return_values.append([
'mstore',
['add', output_placeholder, static_offset], 'pass'
])
static_offset += 32
# append dynamic unpacker.
dyn_idx = 0
for in_memory_offset, out_type in dynamic_offsets:
ident = "%d_%d_arg_%d" % (stmt_expr.lineno,
stmt_expr.col_offset, dyn_idx)
dyn_idx += 1
start_label = 'dyn_unpack_start_' + ident
end_label = 'dyn_unpack_end_' + ident
i_placeholder = context.new_placeholder(
typ=BaseType('uint256'))
begin_pos = ['add', output_placeholder, in_memory_offset]
# loop until length.
o = LLLnode.from_list(
[
'seq_unchecked',
['mstore', begin_pos, 'pass'], # get len
['mstore', i_placeholder, 0],
['label', start_label],
[
'if',
[
'ge', ['mload', i_placeholder],
['ceil32', ['mload', begin_pos]]
], ['goto', end_label]
], # break
[
'mstore',
[
'add', ['add', begin_pos, 32],
['mload', i_placeholder]
], 'pass'
], # pop into correct memory slot.
[
'mstore', i_placeholder,
['add', 32, ['mload', i_placeholder]]
], # increment i
['goto', start_label],
['label', end_label]
],
typ=None,
annotation='dynamic unpacker',
pos=getpos(stmt_expr))
pop_return_values.append(o)
o = LLLnode.from_list(['seq_unchecked'] + pre_init + push_local_vars +
push_args + jump_to_func + pop_return_values +
pop_local_vars + [returner],
typ=sig.output_type,
location='memory',
pos=getpos(stmt_expr),
annotation='Internal Call: %s' % method_name,
add_gas_estimate=sig.gas)
o.gas += sig.gas
return o
def arithmetic(self):
pre_alloc_left, left = self.arithmetic_get_reference(self.expr.left)
pre_alloc_right, right = self.arithmetic_get_reference(self.expr.right)
if not is_numeric_type(left.typ) or not is_numeric_type(right.typ):
raise TypeMismatchException("Unsupported types for arithmetic op: %r %r" % (left.typ, right.typ), self.expr)
arithmetic_pair = {left.typ.typ, right.typ.typ}
# Special Case: Simplify any literal to literal arithmetic at compile time.
if left.typ.is_literal and right.typ.is_literal and \
isinstance(right.value, int) and isinstance(left.value, int):
if isinstance(self.expr.op, ast.Add):
val = left.value + right.value
elif isinstance(self.expr.op, ast.Sub):
val = left.value - right.value
elif isinstance(self.expr.op, ast.Mult):
val = left.value * right.value
elif isinstance(self.expr.op, ast.Div):
val = left.value // right.value
elif isinstance(self.expr.op, ast.Mod):
val = left.value % right.value
elif isinstance(self.expr.op, ast.Pow):
val = left.value ** right.value
else:
raise ParserException('Unsupported literal operator: %s' % str(type(self.expr.op)), self.expr)
num = ast.Num(val)
num.source_code = self.expr.source_code
num.lineno = self.expr.lineno
num.col_offset = self.expr.col_offset
return Expr.parse_value_expr(num, self.context)
# Special case with uint256 were int literal may be casted.
if arithmetic_pair == {'uint256', 'int128'}:
# Check right side literal.
if right.typ.is_literal and SizeLimits.in_bounds('uint256', right.value):
right = LLLnode.from_list(right.value, typ=BaseType('uint256', None, is_literal=True), pos=getpos(self.expr))
arithmetic_pair = {left.typ.typ, right.typ.typ}
# Check left side literal.
elif left.typ.is_literal and SizeLimits.in_bounds('uint256', left.value):
left = LLLnode.from_list(left.value, typ=BaseType('uint256', None, is_literal=True), pos=getpos(self.expr))
arithmetic_pair = {left.typ.typ, right.typ.typ}
# Only allow explicit conversions to occur.
if left.typ.typ != right.typ.typ:
raise TypeMismatchException("Cannot implicitly convert {} to {}.".format(left.typ.typ, right.typ.typ), self.expr)
ltyp, rtyp = left.typ.typ, right.typ.typ
if isinstance(self.expr.op, (ast.Add, ast.Sub)):
if left.typ.unit != right.typ.unit and left.typ.unit is not None and right.typ.unit is not None:
raise TypeMismatchException("Unit mismatch: %r %r" % (left.typ.unit, right.typ.unit), self.expr)
if left.typ.positional and right.typ.positional and isinstance(self.expr.op, ast.Add):
raise TypeMismatchException("Cannot add two positional units!", self.expr)
new_unit = left.typ.unit or right.typ.unit
new_positional = left.typ.positional ^ right.typ.positional # xor, as subtracting two positionals gives a delta
op = 'add' if isinstance(self.expr.op, ast.Add) else 'sub'
if ltyp == 'uint256' and isinstance(self.expr.op, ast.Add):
o = LLLnode.from_list(['seq',
# Checks that: a + b >= a
['assert', ['ge', ['add', left, right], left]],
['add', left, right]], typ=BaseType('uint256', new_unit, new_positional), pos=getpos(self.expr))
elif ltyp == 'uint256' and isinstance(self.expr.op, ast.Sub):
o = LLLnode.from_list(['seq',
# Checks that: a >= b
['assert', ['ge', left, right]],
['sub', left, right]], typ=BaseType('uint256', new_unit, new_positional), pos=getpos(self.expr))
elif ltyp == rtyp:
o = LLLnode.from_list([op, left, right], typ=BaseType(ltyp, new_unit, new_positional), pos=getpos(self.expr))
else:
raise Exception("Unsupported Operation '%r(%r, %r)'" % (op, ltyp, rtyp))
elif isinstance(self.expr.op, ast.Mult):
if left.typ.positional or right.typ.positional:
raise TypeMismatchException("Cannot multiply positional values!", self.expr)
new_unit = combine_units(left.typ.unit, right.typ.unit)
if ltyp == rtyp == 'uint256':
o = LLLnode.from_list(['if', ['eq', left, 0], [0],
['seq', ['assert', ['eq', ['div', ['mul', left, right], left], right]],
['mul', left, right]]], typ=BaseType('uint256', new_unit), pos=getpos(self.expr))
elif ltyp == rtyp == 'int128':
o = LLLnode.from_list(['mul', left, right], typ=BaseType('int128', new_unit), pos=getpos(self.expr))
elif ltyp == rtyp == 'decimal':
o = LLLnode.from_list(['with', 'r', right, ['with', 'l', left,
['with', 'ans', ['mul', 'l', 'r'],
['seq',
['assert', ['or', ['eq', ['sdiv', 'ans', 'l'], 'r'], ['iszero', 'l']]],
['sdiv', 'ans', DECIMAL_DIVISOR]]]]], typ=BaseType('decimal', new_unit), pos=getpos(self.expr))
else:
raise Exception("Unsupported Operation 'mul(%r, %r)'" % (ltyp, rtyp))
elif isinstance(self.expr.op, ast.Div):
if left.typ.positional or right.typ.positional:
raise TypeMismatchException("Cannot divide positional values!", self.expr)
new_unit = combine_units(left.typ.unit, right.typ.unit, div=True)
if ltyp == rtyp == 'uint256':
o = LLLnode.from_list(['seq',
# Checks that: b != 0
['assert', right],
['div', left, right]], typ=BaseType('uint256', new_unit), pos=getpos(self.expr))
elif ltyp == rtyp == 'int128':
o = LLLnode.from_list(['sdiv', left, ['clamp_nonzero', right]], typ=BaseType('int128', new_unit), pos=getpos(self.expr))
elif ltyp == rtyp == 'decimal':
o = LLLnode.from_list(['with', 'l', left, ['with', 'r', ['clamp_nonzero', right],
['sdiv', ['mul', 'l', DECIMAL_DIVISOR], 'r']]],
typ=BaseType('decimal', new_unit), pos=getpos(self.expr))
else:
raise Exception("Unsupported Operation 'div(%r, %r)'" % (ltyp, rtyp))
elif isinstance(self.expr.op, ast.Mod):
if left.typ.positional or right.typ.positional:
raise TypeMismatchException("Cannot use positional values as modulus arguments!", self.expr)
if left.typ.unit != right.typ.unit and left.typ.unit is not None and right.typ.unit is not None:
raise TypeMismatchException("Modulus arguments must have same unit", self.expr)
new_unit = left.typ.unit or right.typ.unit
if ltyp == rtyp == 'uint256':
o = LLLnode.from_list(['seq',
['assert', right],
['mod', left, right]], typ=BaseType('uint256', new_unit), pos=getpos(self.expr))
elif ltyp == rtyp:
o = LLLnode.from_list(['smod', left, ['clamp_nonzero', right]], typ=BaseType(ltyp, new_unit), pos=getpos(self.expr))
else:
raise Exception("Unsupported Operation 'mod(%r, %r)'" % (ltyp, rtyp))
elif isinstance(self.expr.op, ast.Pow):
if left.typ.positional or right.typ.positional:
raise TypeMismatchException("Cannot use positional values as exponential arguments!", self.expr)
if right.typ.unit:
raise TypeMismatchException("Cannot use unit values as exponents", self.expr)
if ltyp != 'int128' and ltyp != 'uint256' and isinstance(self.expr.right, ast.Name):
raise TypeMismatchException("Cannot use dynamic values as exponents, for unit base types", self.expr)
if ltyp == rtyp == 'uint256':
o = LLLnode.from_list(['seq',
['assert', ['or', ['or', ['eq', right, 1], ['iszero', right]],
['lt', left, ['exp', left, right]]]],
['exp', left, right]], typ=BaseType('uint256'), pos=getpos(self.expr))
elif ltyp == rtyp == 'int128':
new_unit = left.typ.unit
if left.typ.unit and not isinstance(self.expr.right, ast.Name):
new_unit = {left.typ.unit.copy().popitem()[0]: self.expr.right.n}
o = LLLnode.from_list(['exp', left, right], typ=BaseType('int128', new_unit), pos=getpos(self.expr))
else:
raise TypeMismatchException('Only whole number exponents are supported', self.expr)
else:
raise Exception("Unsupported binop: %r" % self.expr.op)
p = ['seq']
if pre_alloc_left:
p.append(pre_alloc_left)
if pre_alloc_right:
p.append(pre_alloc_right)
if o.typ.typ == 'int128':
p.append(['clamp', ['mload', MemoryPositions.MINNUM], o, ['mload', MemoryPositions.MAXNUM]])
return LLLnode.from_list(p, typ=o.typ, pos=getpos(self.expr))
elif o.typ.typ == 'decimal':
p.append(['clamp', ['mload', MemoryPositions.MINDECIMAL], o, ['mload', MemoryPositions.MAXDECIMAL]])
return LLLnode.from_list(p, typ=o.typ, pos=getpos(self.expr))
if o.typ.typ == 'uint256':
p.append(o)
return LLLnode.from_list(p, typ=o.typ, pos=getpos(self.expr))
else:
raise Exception("%r %r" % (o, o.typ))
def attribute(self):
# x.balance: balance of address x
if self.expr.attr == 'balance':
addr = Expr.parse_value_expr(self.expr.value, self.context)
if not is_base_type(addr.typ, 'address'):
raise TypeMismatchException("Type mismatch: balance keyword expects an address as input", self.expr)
return LLLnode.from_list(['balance', addr], typ=BaseType('uint256', {'wei': 1}), location=None, pos=getpos(self.expr))
# x.codesize: codesize of address x
elif self.expr.attr == 'codesize' or self.expr.attr == 'is_contract':
addr = Expr.parse_value_expr(self.expr.value, self.context)
if not is_base_type(addr.typ, 'address'):
raise TypeMismatchException("Type mismatch: codesize keyword expects an address as input", self.expr)
if self.expr.attr == 'codesize':
eval_code = ['extcodesize', addr]
output_type = 'int128'
else:
eval_code = ['gt', ['extcodesize', addr], 0]
output_type = 'bool'
return LLLnode.from_list(eval_code, typ=BaseType(output_type), location=None, pos=getpos(self.expr))
# self.x: global attribute
elif isinstance(self.expr.value, ast.Name) and self.expr.value.id == "self":
if self.expr.attr not in self.context.globals:
raise VariableDeclarationException("Persistent variable undeclared: " + self.expr.attr, self.expr)
var = self.context.globals[self.expr.attr]
return LLLnode.from_list(var.pos, typ=var.typ, location='storage', pos=getpos(self.expr), annotation='self.' + self.expr.attr)
# Reserved keywords
elif isinstance(self.expr.value, ast.Name) and self.expr.value.id in ("msg", "block", "tx"):
key = self.expr.value.id + "." + self.expr.attr
if key == "msg.sender":
if self.context.is_private:
raise ParserException("msg.sender not allowed in private functions.", self.expr)
return LLLnode.from_list(['caller'], typ='address', pos=getpos(self.expr))
elif key == "msg.value":
if not self.context.is_payable:
raise NonPayableViolationException("Cannot use msg.value in a non-payable function", self.expr)
return LLLnode.from_list(['callvalue'], typ=BaseType('uint256', {'wei': 1}), pos=getpos(self.expr))
elif key == "msg.gas":
return LLLnode.from_list(['gas'], typ='uint256', pos=getpos(self.expr))
elif key == "block.difficulty":
return LLLnode.from_list(['difficulty'], typ='uint256', pos=getpos(self.expr))
elif key == "block.timestamp":
return LLLnode.from_list(['timestamp'], typ=BaseType('uint256', {'sec': 1}, True), pos=getpos(self.expr))
elif key == "block.coinbase":
return LLLnode.from_list(['coinbase'], typ='address', pos=getpos(self.expr))
elif key == "block.number":
return LLLnode.from_list(['number'], typ='uint256', pos=getpos(self.expr))
elif key == "block.prevhash":
return LLLnode.from_list(['blockhash', ['sub', 'number', 1]], typ='bytes32', pos=getpos(self.expr))
elif key == "tx.origin":
return LLLnode.from_list(['origin'], typ='address', pos=getpos(self.expr))
else:
raise Exception("Unsupported keyword: " + key)
# Other variables
else:
sub = Expr.parse_variable_location(self.expr.value, self.context)
# contract type
if isinstance(sub.typ, ContractType):
return sub
if not isinstance(sub.typ, StructType):
raise TypeMismatchException("Type mismatch: member variable access not expected", self.expr.value)
attrs = sorted(sub.typ.members.keys())
if self.expr.attr not in attrs:
raise TypeMismatchException("Member %s not found. Only the following available: %s" % (self.expr.attr, " ".join(attrs)), self.expr)
return add_variable_offset(sub, self.expr.attr, pos=getpos(self.expr))
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))
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))
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))
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)
)
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))
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))
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)
)
else:
raise TypeMismatchException("Can only return base type!", 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))
i_pos = self.context.new_variable('_index_for_' + varname, BaseType(subtype))
self.context.forvars[varname] = True
if iter_var_type: # Is a list that is already allocated to memory.
self.context.set_in_for_loop(self.stmt.iter.id) # 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)
)
self.context.remove_in_for_loop(self.stmt.iter.id)
elif isinstance(self.stmt.iter, ast.List): # List gets defined in the for statement.
# 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)
)
elif isinstance(self.stmt.iter, ast.Attribute): # List is contained in storage.
count = iter_list_node.typ.count
self.context.set_in_for_loop(iter_list_node.annotation) # 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)
)
self.context.remove_in_for_loop(iter_list_node.annotation)
del self.context.vars[varname]
del self.context.vars['_index_for_' + varname]
del self.context.forvars[varname]
return o