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, 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', ['seq', lll_ret]]
]
return lll_ret
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, sri_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 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, sri_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, sri_ast.Tuple)) and isinstance(
self.stmt.value, sri_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_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 abi_encode(dst, lll_node, pos=None, bufsz=None, returns=False):
parent_abi_t = abi_type_of(lll_node.typ)
size_bound = parent_abi_t.static_size() + parent_abi_t.dynamic_size_bound()
if bufsz is not None and bufsz < 32 * size_bound:
raise CompilerPanic('buffer provided to abi_encode not large enough')
lll_ret = ['seq']
dyn_ofst = 'dyn_ofst' # current offset in the dynamic section
dst_begin = 'dst' # pointer to beginning of buffer
dst_loc = 'dst_loc' # pointer to write location in static section
os = o_list(lll_node, pos=pos)
for i, o in enumerate(os):
abi_t = abi_type_of(o.typ)
if parent_abi_t.is_tuple():
if abi_t.is_dynamic():
lll_ret.append(['mstore', dst_loc, dyn_ofst])
# recurse
child_dst = ['add', dst_begin, dyn_ofst]
child = abi_encode(child_dst, o, pos=pos, returns=True)
# increment dyn ofst for the return
# (optimization note:
# if non-returning and this is the last dyn member in
# the tuple, this set can be elided.)
lll_ret.append(['set', dyn_ofst, ['add', dyn_ofst, child]])
else:
# recurse
lll_ret.append(abi_encode(dst_loc, o, pos=pos, returns=False))
elif isinstance(o.typ, BaseType):
d = LLLnode(dst_loc, typ=o.typ, location='memory')
lll_ret.append(make_setter(d, o, location=d.location, pos=pos))
elif isinstance(o.typ, ByteArrayLike):
d = LLLnode.from_list(dst_loc, typ=o.typ, location='memory')
lll_ret.append([
'seq',
make_setter(d, o, location=d.location, pos=pos),
zero_pad(d)
])
else:
raise CompilerPanic(f'unreachable type: {o.typ}')
if i + 1 == len(os):
pass # optimize out the last increment to dst_loc
else: # note: always false for non-tuple types
sz = abi_t.embedded_static_size()
lll_ret.append(['set', dst_loc, ['add', dst_loc, sz]])
# declare LLL variables.
if returns:
if not parent_abi_t.is_dynamic():
lll_ret.append(parent_abi_t.embedded_static_size())
elif parent_abi_t.is_tuple():
lll_ret.append('dyn_ofst')
elif isinstance(lll_node.typ, ByteArrayLike):
# for abi purposes, return zero-padded length
calc_len = ['ceil32', ['add', 32, ['mload', dst_loc]]]
lll_ret.append(calc_len)
else:
raise CompilerPanic('unknown type {lll_node.typ}')
if not (parent_abi_t.is_dynamic() and parent_abi_t.is_tuple()):
pass # optimize out dyn_ofst allocation if we don't need it
else:
dyn_section_start = parent_abi_t.static_size()
lll_ret = ['with', 'dyn_ofst', dyn_section_start, lll_ret]
lll_ret = ['with', dst_begin, dst, ['with', dst_loc, dst_begin, lll_ret]]
return LLLnode.from_list(lll_ret)
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, (sri_ast.Str, sri_ast.Call)):
expr = Expr(arg, context)
source_lll = expr.lll_node
typ = source_lll.typ
if isinstance(arg, sri_ast.Str):
if len(arg.s) > typ.maxlen:
raise TypeMismatch(
f"Data input bytes are to big: {len(arg.s)} {typ}", pos
)
tmp_variable = context.new_internal_variable(
f'_log_pack_var_{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=f'log_prealloacted {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:
dynamic_offset_counter = context.new_placeholder(BaseType(32))
dynamic_placeholder = context.new_placeholder(BaseType(32))
else:
dynamic_offset_counter = 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,
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,
pos=pos
)
return holder, maxlen, dynamic_offset_counter, datamem_start
def check_assign(lhs, rhs, pos, in_function_call=False):
make_setter(lhs,
rhs,
location='memory',
pos=pos,
in_function_call=in_function_call)
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 TypeMismatch("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 TypeMismatch("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 self.context.return_type != sub.typ and not sub.typ.is_literal:
raise TypeMismatch(
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 InvalidLiteral(
"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 TypeMismatch(
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 TypeMismatch(
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 TypeMismatch(
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):
loop_memory_position = self.context.new_placeholder(
typ=BaseType('uint256'))
if sub.typ != self.context.return_type:
raise TypeMismatch(
f"List return type {sub.typ} does not match specified "
f"return type, expecting {self.context.return_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 TypeMismatch(
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 TypeMismatch(
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 TypeMismatch(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, sri_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_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(
f'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, sri_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, sri_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