def unwrap_location(orig):
if orig.location == "memory":
return LLLnode.from_list(["mload", orig], typ=orig.typ)
elif orig.location == "storage":
return LLLnode.from_list(["sload", orig], typ=orig.typ)
elif orig.location == "calldata":
return LLLnode.from_list(["calldataload", orig], typ=orig.typ)
else:
# handle None value inserted by `empty`
if orig.value is None:
return LLLnode.from_list(0, typ=orig.typ)
return orig
def _make_array_index_setter(target, target_token, pos, location, offset):
if location == "memory" and isinstance(target.value, int):
offset = target.value + 32 * get_size_of_type(
target.typ.subtype) * offset
return LLLnode.from_list([offset],
typ=target.typ.subtype,
location=location,
pos=pos)
else:
return add_variable_offset(
target_token,
LLLnode.from_list(offset, typ="int256"),
pos=pos,
array_bounds_check=False,
)
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 lazy_abi_decode(typ, src, pos=None):
if isinstance(typ, (ListType, TupleLike)):
if isinstance(typ, TupleLike):
ts = typ.tuple_members()
else:
ts = [typ.subtyp for _ in range(typ.count)]
ofst = 0
os = []
for t in ts:
child_abi_t = abi_type_of(t)
loc = _add_ofst(src, ofst)
if child_abi_t.is_dynamic():
# load the offset word, which is the
# (location-independent) offset from the start of the
# src buffer.
dyn_ofst = unwrap_location(ofst)
loc = _add_ofst(src, dyn_ofst)
os.append(lazy_abi_decode(t, loc, pos))
ofst += child_abi_t.embedded_static_size()
return LLLnode.from_list(["multi"] + os, typ=typ, pos=pos)
elif isinstance(typ, (BaseType, ByteArrayLike)):
return unwrap_location(src)
else:
raise CompilerPanic(f"unknown type for lazy_abi_decode {typ}")
def mzero(dst, nbytes):
# calldatacopy from past-the-end gives zero bytes.
# cf. YP H.2 (ops section) with CALLDATACOPY spec.
return LLLnode.from_list(
# calldatacopy mempos calldatapos len
["calldatacopy", dst, "calldatasize", nbytes],
annotation="mzero",
)
def byte_array_to_num(
arg,
expr,
out_type,
offset=32,
):
if arg.location == "memory":
lengetter = LLLnode.from_list(["mload", "_sub"],
typ=BaseType("int256"))
first_el_getter = LLLnode.from_list(["mload", ["add", 32, "_sub"]],
typ=BaseType("int256"))
elif arg.location == "storage":
lengetter = LLLnode.from_list(["sload", "_sub"],
typ=BaseType("int256"))
first_el_getter = LLLnode.from_list(["sload", ["add", 1, "_sub"]],
typ=BaseType("int256"))
if out_type == "int128":
result = int128_clamp(
["div", "_el1", ["exp", 256, ["sub", 32, "_len"]]])
elif out_type in ("int256", "uint256"):
result = ["div", "_el1", ["exp", 256, ["sub", offset, "_len"]]]
return LLLnode.from_list(
[
"with",
"_sub",
arg,
[
"with",
"_el1",
first_el_getter,
["with", "_len", ["clamp", 0, lengetter, 32], result],
],
],
typ=BaseType(out_type),
annotation=f"bytearray to number ({out_type})",
)
def o_list(lll_node, pos=None):
lll_t = lll_node.typ
if isinstance(lll_t, (TupleLike, ListType)):
if lll_node.value == "multi": # is literal
ret = lll_node.args
else:
ks = (lll_t.tuple_keys() if isinstance(lll_t, TupleLike) else [
LLLnode.from_list(i, "uint256") for i in range(lll_t.count)
])
ret = [
add_variable_offset(lll_node, k, pos, array_bounds_check=False)
for k in ks
]
return ret
else:
return [lll_node]
def zero_pad(bytez_placeholder):
len_ = ["mload", bytez_placeholder]
dst = ["add", ["add", bytez_placeholder, 32], "len"]
# the runtime length of the data rounded up to nearest 32
# from spec:
# the actual value of X as a byte sequence,
# followed by the *minimum* number of zero-bytes
# such that len(enc(X)) is a multiple of 32.
num_zero_bytes = ["sub", ["ceil32", "len"], "len"]
return LLLnode.from_list(
[
"with", "len", len_,
["with", "dst", dst,
mzero("dst", num_zero_bytes)]
],
annotation="Zero pad",
)
def keccak256_helper(expr, args, kwargs, context):
sub = args[0]
# Can hash literals
if isinstance(sub, bytes):
return LLLnode.from_list(
bytes_to_int(keccak256(sub)), typ=BaseType("bytes32"), pos=getpos(expr)
)
# Can hash bytes32 objects
if is_base_type(sub.typ, "bytes32"):
return LLLnode.from_list(
[
"seq",
["mstore", MemoryPositions.FREE_VAR_SPACE, sub],
["sha3", MemoryPositions.FREE_VAR_SPACE, 32],
],
typ=BaseType("bytes32"),
pos=getpos(expr),
)
# Copy the data to an in-memory array
if sub.location == "memory":
# If we are hashing a value in memory, no need to copy it, just hash in-place
return LLLnode.from_list(
["with", "_sub", sub, ["sha3", ["add", "_sub", 32], ["mload", "_sub"]]],
typ=BaseType("bytes32"),
pos=getpos(expr),
)
elif sub.location == "storage":
lengetter = LLLnode.from_list(["sload", "_sub"], typ=BaseType("int128"))
else:
# This should never happen, but just left here for future compiler-writers.
raise Exception(f"Unsupported location: {sub.location}") # pragma: no test
placeholder = context.new_internal_variable(sub.typ)
placeholder_node = LLLnode.from_list(placeholder, typ=sub.typ, location="memory")
copier = make_byte_array_copier(
placeholder_node, LLLnode.from_list("_sub", typ=sub.typ, location=sub.location),
)
return LLLnode.from_list(
["with", "_sub", sub, ["seq", copier, ["sha3", ["add", placeholder, 32], lengetter]]],
typ=BaseType("bytes32"),
pos=getpos(expr),
)
def add_variable_offset(parent, key, pos, array_bounds_check=True):
typ, location = parent.typ, parent.location
if isinstance(typ, TupleLike):
if isinstance(typ, StructType):
subtype = typ.members[key]
attrs = list(typ.tuple_keys())
index = attrs.index(key)
annotation = key
else:
attrs = list(range(len(typ.members)))
index = key
annotation = None
if location == "storage":
# for arrays and structs, calculate the storage slot by adding an offset
# of [index value being accessed] * [size of each item within the sequence]
offset = 0
for i in range(index):
offset += get_size_of_type(typ.members[attrs[i]])
return LLLnode.from_list(
["add", parent, offset],
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 in ("calldata", "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=location,
annotation=annotation,
)
elif isinstance(typ, MappingType):
sub = None
if isinstance(key.typ, ByteArrayLike):
if isinstance(
typ.keytype,
ByteArrayLike) and (typ.keytype.maxlen >= key.typ.maxlen):
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:
value = key.args[0].value
if value == "add":
# special case, key is a bytes array within a tuple/struct
value = key.args[0]
sub = LLLnode.from_list(["sha3", ["add", value, 32], key])
else:
subtype = typ.valuetype
sub = unwrap_location(key)
if sub is not None and location == "storage":
return LLLnode.from_list(["sha3_64", parent, sub],
typ=subtype,
location="storage")
elif isinstance(typ, ListType) and is_base_type(
key.typ, ("int128", "int256", "uint256")):
subtype = typ.subtype
k = unwrap_location(key)
if not array_bounds_check:
sub = k
elif key.typ.is_literal: # note: BaseType always has is_literal attr
# perform the check at compile time and elide the runtime check.
if key.value < 0 or key.value >= typ.count:
return
sub = k
else:
# this works, even for int128. for int128, since two's-complement
# is used, if the index is negative, (unsigned) LT will interpret
# it as a very large number, larger than any practical value for
# an array index, and the clamp will throw an error.
sub = ["uclamplt", k, typ.count]
if location == "storage":
# storage slot determined as [initial storage slot] + [index] * [size of base type]
offset = get_size_of_type(subtype)
return LLLnode.from_list(["add", parent, ["mul", sub, offset]],
typ=subtype,
location="storage",
pos=pos)
elif location == "storage_prehashed":
return LLLnode.from_list(["add", parent, sub],
typ=subtype,
location="storage",
pos=pos)
elif location in ("calldata", "memory"):
offset = 32 * get_size_of_type(subtype)
return LLLnode.from_list(["add", ["mul", offset, sub], parent],
typ=subtype,
location=location,
pos=pos)
def parse_tree_to_lll(global_ctx: GlobalContext) -> Tuple[LLLnode, LLLnode]:
_names_def = [_def.name for _def in global_ctx._defs]
# Checks for duplicate function names
if len(set(_names_def)) < len(_names_def):
raise FunctionDeclarationException(
"Duplicate function name: "
f"{[name for name in _names_def if _names_def.count(name) > 1][0]}"
)
_names_events = [_event.name for _event in global_ctx._events]
# Checks for duplicate event names
if len(set(_names_events)) < len(_names_events):
raise EventDeclarationException(f"""Duplicate event name:
{[name for name in _names_events if _names_events.count(name) > 1][0]}"""
)
# Initialization function
initfunc = [_def for _def in global_ctx._defs if is_initializer(_def)]
# Default function
defaultfunc = next((i for i in global_ctx._defs if is_default_func(i)),
None)
# Regular functions
otherfuncs = [
_def for _def in global_ctx._defs
if not is_initializer(_def) and not is_default_func(_def)
]
sigs: dict = {}
external_interfaces: dict = {}
# Create the main statement
o = ["seq"]
if global_ctx._contracts or global_ctx._interfaces:
external_interfaces = parse_external_interfaces(
external_interfaces, global_ctx)
# If there is an init func...
if initfunc:
o.append(init_func_init_lll())
o.append(
parse_function(
initfunc[0],
{
**{
"self": sigs
},
**external_interfaces
},
global_ctx,
False,
))
# If there are regular functions...
if otherfuncs or defaultfunc:
o, runtime = parse_other_functions(
o,
otherfuncs,
sigs,
external_interfaces,
global_ctx,
defaultfunc,
)
else:
runtime = o.copy()
return LLLnode.from_list(o, typ=None), LLLnode.from_list(runtime, typ=None)
def func_init_lll():
return LLLnode.from_list(STORE_CALLDATA + LIMIT_MEMORY_SET, typ=None)
def get_length(arg):
if arg.location == "memory":
return LLLnode.from_list(["mload", arg], typ=BaseType("uint256"))
elif arg.location == "storage":
return LLLnode.from_list(["sload", arg], typ=BaseType("uint256"))
def make_external_call(stmt_expr, context):
# circular import!
from vyper.old_codegen.expr import Expr
value, gas = get_external_interface_keywords(stmt_expr, context)
if isinstance(stmt_expr.func, vy_ast.Attribute) and isinstance(
stmt_expr.func.value, vy_ast.Call):
contract_name = stmt_expr.func.value.func.id
contract_address = Expr.parse_value_expr(stmt_expr.func.value.args[0],
context)
return external_call(
stmt_expr,
context,
contract_name,
contract_address,
pos=getpos(stmt_expr),
value=value,
gas=gas,
)
elif (isinstance(stmt_expr.func.value, vy_ast.Attribute)
and stmt_expr.func.value.attr in context.sigs): # noqa: E501
contract_name = stmt_expr.func.value.attr
type_ = stmt_expr.func.value._metadata["type"]
var = context.globals[stmt_expr.func.value.attr]
contract_address = unwrap_location(
LLLnode.from_list(
type_.position.position,
typ=var.typ,
location="storage",
pos=getpos(stmt_expr),
annotation="self." + stmt_expr.func.value.attr,
))
return external_call(
stmt_expr,
context,
contract_name,
contract_address,
pos=getpos(stmt_expr),
value=value,
gas=gas,
)
elif (isinstance(stmt_expr.func.value, vy_ast.Attribute)
and stmt_expr.func.value.attr in context.globals
and hasattr(context.globals[stmt_expr.func.value.attr].typ, "name")):
contract_name = context.globals[stmt_expr.func.value.attr].typ.name
type_ = stmt_expr.func.value._metadata["type"]
var = context.globals[stmt_expr.func.value.attr]
contract_address = unwrap_location(
LLLnode.from_list(
type_.position.position,
typ=var.typ,
location="storage",
pos=getpos(stmt_expr),
annotation="self." + stmt_expr.func.value.attr,
))
return external_call(
stmt_expr,
context,
contract_name,
contract_address,
pos=getpos(stmt_expr),
value=value,
gas=gas,
)
else:
raise StructureException("Unsupported operator.", stmt_expr)
def parse_other_functions(o, otherfuncs, sigs, external_interfaces, global_ctx,
default_function):
# check for payable/nonpayable external functions to optimize nonpayable assertions
func_types = [i._metadata["type"] for i in global_ctx._defs]
mutabilities = [
i.mutability for i in func_types
if i.visibility == FunctionVisibility.EXTERNAL
]
has_payable = next(
(True for i in mutabilities if i == StateMutability.PAYABLE), False)
has_nonpayable = next(
(True for i in mutabilities if i != StateMutability.PAYABLE), False)
is_default_payable = (default_function is not None
and default_function._metadata["type"].mutability
== StateMutability.PAYABLE)
# when a contract has a payable default function and at least one nonpayable
# external function, we must perform the nonpayable check on every function
check_per_function = is_default_payable and has_nonpayable
# generate LLL for regular functions
payable_func_sub = ["seq"]
external_func_sub = ["seq"]
internal_func_sub = ["seq"]
add_gas = func_init_lll().gas
for func_node in otherfuncs:
func_type = func_node._metadata["type"]
func_lll = parse_function(func_node, {
**{
"self": sigs
},
**external_interfaces
}, global_ctx, check_per_function)
if func_type.visibility == FunctionVisibility.INTERNAL:
internal_func_sub.append(func_lll)
elif func_type.mutability == StateMutability.PAYABLE:
add_gas += 30
payable_func_sub.append(func_lll)
else:
external_func_sub.append(func_lll)
add_gas += 30
func_lll.total_gas += add_gas
for sig in sig_utils.generate_default_arg_sigs(func_node,
external_interfaces,
global_ctx):
sig.gas = func_lll.total_gas
sigs[sig.sig] = sig
# generate LLL for fallback function
if default_function:
fallback_lll = parse_function(
default_function,
{
**{
"self": sigs
},
**external_interfaces
},
global_ctx,
# include a nonpayble check here if the contract only has a default function
check_per_function or not otherfuncs,
)
else:
fallback_lll = LLLnode.from_list(["revert", 0, 0],
typ=None,
annotation="Default function")
if check_per_function:
external_seq = ["seq", payable_func_sub, external_func_sub]
else:
# payable functions are placed prior to nonpayable functions
# and seperated by a nonpayable assertion
external_seq = ["seq"]
if has_payable:
external_seq.append(payable_func_sub)
if has_nonpayable:
external_seq.extend([["assert", ["iszero", "callvalue"]],
external_func_sub])
# bytecode is organized by: external functions, fallback fn, internal functions
# this way we save gas and reduce bytecode by not jumping over internal functions
main_seq = [
"seq",
func_init_lll(),
["with", "_func_sig", ["mload", 0], external_seq],
["seq_unchecked", ["label", "fallback"], fallback_lll],
internal_func_sub,
]
o.append(["return", 0, ["lll", main_seq, 0]])
return o, main_seq
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 make_setter(left, right, location, pos, in_function_call=False):
# Basic types
if isinstance(left.typ, BaseType):
right = unwrap_location(right)
if location == "storage":
return LLLnode.from_list(["sstore", left, right], typ=None)
elif location == "memory":
return LLLnode.from_list(["mstore", left, right], typ=None)
# Byte arrays
elif isinstance(left.typ, ByteArrayLike):
return make_byte_array_copier(left, right, pos)
# Can't copy mappings
elif isinstance(left.typ, MappingType):
raise TypeMismatch(
"Cannot copy mappings; can only copy individual elements", pos)
# Arrays
elif isinstance(left.typ, ListType):
# Cannot do something like [a, b, c] = [1, 2, 3]
if left.value == "multi":
return
if not isinstance(right.typ, ListType):
return
if right.typ.count != left.typ.count:
return
left_token = LLLnode.from_list("_L",
typ=left.typ,
location=left.location)
# If the right side is a literal
if right.value in ["multi", "seq_unchecked"] and right.typ.is_literal:
if right.value == "seq_unchecked":
# when the LLL is `seq_unchecked`, this is a literal where one or
# more values must be pre-processed to avoid memory corruption
subs = right.args[:-1]
right = right.args[-1]
else:
subs = []
for i in range(left.typ.count):
lhs_setter = _make_array_index_setter(left, left_token, pos,
location, i)
subs.append(
make_setter(
lhs_setter,
right.args[i],
location,
pos=pos,
))
if left.location == "memory" and isinstance(left.value, int):
return LLLnode.from_list(["seq"] + subs, typ=None)
else:
return LLLnode.from_list(["with", "_L", left, ["seq"] + subs],
typ=None)
elif right.value is None:
if right.typ != left.typ:
return
if left.location == "memory":
return mzero(left, 32 * get_size_of_type(left.typ))
subs = []
for i in range(left.typ.count):
subs.append(
make_setter(
add_variable_offset(
left_token,
LLLnode.from_list(i, typ="int256"),
pos=pos,
array_bounds_check=False,
),
LLLnode.from_list(None, typ=right.typ.subtype),
location,
pos=pos,
))
return LLLnode.from_list(["with", "_L", left, ["seq"] + subs],
typ=None)
# If the right side is a variable
else:
right_token = LLLnode.from_list("_R",
typ=right.typ,
location=right.location)
subs = []
for i in range(left.typ.count):
lhs_setter = _make_array_index_setter(left, left_token, pos,
left.location, i)
rhs_setter = _make_array_index_setter(right, right_token, pos,
right.location, i)
subs.append(
make_setter(
lhs_setter,
rhs_setter,
location,
pos=pos,
))
lll_node = ["seq"] + subs
if right.location != "memory" or not isinstance(right.value, int):
lll_node = ["with", "_R", right, lll_node]
if left.location != "memory" or not isinstance(left.value, int):
lll_node = ["with", "_L", left, lll_node]
return LLLnode.from_list(lll_node, typ=None)
# Structs
elif isinstance(left.typ, TupleLike):
if left.value == "multi" and isinstance(left.typ, StructType):
return
if right.value is not None:
if not isinstance(right.typ, left.typ.__class__):
return
if isinstance(left.typ, StructType):
for k in left.typ.members:
if k not in right.typ.members:
return
for k in right.typ.members:
if k not in left.typ.members:
return
if left.typ.name != right.typ.name:
return
else:
if len(left.typ.members) != len(right.typ.members):
return
left_token = LLLnode.from_list("_L",
typ=left.typ,
location=left.location)
keyz = left.typ.tuple_keys()
# If the left side is a literal
if left.value == "multi":
locations = [arg.location for arg in left.args]
else:
locations = [location for _ in keyz]
# If the right side is a literal
if right.value == "multi":
if len(right.args) != len(keyz):
return
# get the RHS arguments into a dict because
# they are not guaranteed to be in the same order
# the LHS keys.
right_args = dict(zip(right.typ.tuple_keys(), right.args))
subs = []
for (key, loc) in zip(keyz, locations):
subs.append(
make_setter(
add_variable_offset(left_token, key, pos=pos),
right_args[key],
loc,
pos=pos,
))
return LLLnode.from_list(["with", "_L", left, ["seq"] + subs],
typ=None)
# If the right side is a null
elif right.value is None:
if left.typ != right.typ:
return
if left.location == "memory":
return mzero(left, 32 * get_size_of_type(left.typ))
subs = []
for key, loc in zip(keyz, locations):
subs.append(
make_setter(
add_variable_offset(left_token, key, pos=pos),
LLLnode.from_list(None, typ=right.typ.members[key]),
loc,
pos=pos,
))
return LLLnode.from_list(["with", "_L", left, ["seq"] + subs],
typ=None)
# If tuple assign.
elif isinstance(left.typ, TupleType) and isinstance(
right.typ, TupleType):
subs = []
for var_arg in left.args:
if var_arg.location == "calldata":
return
right_token = LLLnode.from_list("_R",
typ=right.typ,
location=right.location)
for left_arg, key, loc in zip(left.args, keyz, locations):
subs.append(
make_setter(left_arg,
add_variable_offset(right_token, key, pos=pos),
loc,
pos=pos))
return LLLnode.from_list(
["with", "_R", right, ["seq"] + subs],
typ=None,
annotation="Tuple assignment",
)
# If the left side is a variable i.e struct type
else:
subs = []
right_token = LLLnode.from_list("_R",
typ=right.typ,
location=right.location)
for typ, loc in zip(keyz, locations):
subs.append(
make_setter(
add_variable_offset(left_token, typ, pos=pos),
add_variable_offset(right_token, typ, pos=pos),
loc,
pos=pos,
))
return LLLnode.from_list(
["with", "_L", left, ["with", "_R", right, ["seq"] + subs]],
typ=None,
)
def make_call(stmt_expr, context):
# ** Internal 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
pop_local_vars = []
push_local_vars = []
pop_return_values = []
push_args = []
method_name = stmt_expr.func.attr
# TODO check this out
from vyper.old_codegen.expr import parse_sequence
pre_init, expr_args = parse_sequence(stmt_expr, stmt_expr.args, context)
sig = FunctionSignature.lookup_sig(
context.sigs,
method_name,
expr_args,
stmt_expr,
context,
)
if context.is_constant() and sig.mutability not in ("view", "pure"):
raise StateAccessViolation(
f"May not call state modifying function "
f"'{method_name}' within {context.pp_constancy()}.",
getpos(stmt_expr),
)
if not sig.internal:
raise StructureException("Cannot call external functions via 'self'",
stmt_expr)
# Push local variables.
var_slots = [(v.pos, v.size) for name, v in context.vars.items()
if v.location == "memory"]
if var_slots:
var_slots.sort(key=lambda x: x[0])
if len(var_slots) > 10:
# if memory is large enough, push and pop it via iteration
mem_from, mem_to = var_slots[0][
0], var_slots[-1][0] + var_slots[-1][1] * 32
i_placeholder = context.new_internal_variable(BaseType("uint256"))
local_save_ident = f"_{stmt_expr.lineno}_{stmt_expr.col_offset}"
push_loop_label = "save_locals_start" + local_save_ident
pop_loop_label = "restore_locals_start" + local_save_ident
push_local_vars = [
["mstore", i_placeholder, mem_from],
["label", push_loop_label],
["mload", ["mload", i_placeholder]],
[
"mstore", i_placeholder,
["add", ["mload", i_placeholder], 32]
],
[
"if", ["lt", ["mload", i_placeholder], mem_to],
["goto", push_loop_label]
],
]
pop_local_vars = [
["mstore", i_placeholder, mem_to - 32],
["label", pop_loop_label],
["mstore", ["mload", i_placeholder], "pass"],
[
"mstore", i_placeholder,
["sub", ["mload", i_placeholder], 32]
],
[
"if", ["ge", ["mload", i_placeholder], mem_from],
["goto", pop_loop_label]
],
]
else:
# for smaller memory, hardcode the mload/mstore locations
push_mem_slots = []
for pos, size in var_slots:
push_mem_slots.extend([pos + i * 32 for i in range(size)])
push_local_vars = [["mload", pos] for pos in push_mem_slots]
pop_local_vars = [["mstore", pos, "pass"]
for pos in push_mem_slots[::-1]]
# Push Arguments
if expr_args:
inargs, inargsize, arg_pos = pack_arguments(sig,
expr_args,
context,
stmt_expr,
is_external_call=False)
push_args += [
inargs
] # copy arguments first, to not mess up the push/pop sequencing.
static_arg_size = 32 * sum(
[get_static_size_of_type(arg.typ) for arg in expr_args])
static_pos = int(arg_pos + static_arg_size)
needs_dyn_section = any(
[has_dynamic_data(arg.typ) for arg in expr_args])
if needs_dyn_section:
ident = f"push_args_{sig.method_id}_{stmt_expr.lineno}_{stmt_expr.col_offset}"
start_label = ident + "_start"
end_label = ident + "_end"
i_placeholder = context.new_internal_variable(BaseType("uint256"))
# Calculate copy start position.
# Given | static | dynamic | section in memory,
# copy backwards so the values are in order on the stack.
# We calculate i, the end of the whole encoded part
# (i.e. the starting index for copy)
# by taking ceil32(len<arg>) + offset<arg> + arg_pos
# for the last dynamic argument and arg_pos is the start
# the whole argument section.
idx = 0
for arg in expr_args:
if isinstance(arg.typ, ByteArrayLike):
last_idx = idx
idx += get_static_size_of_type(arg.typ)
push_args += [[
"with",
"offset",
["mload", arg_pos + last_idx * 32],
[
"with",
"len_pos",
["add", arg_pos, "offset"],
[
"with",
"len_value",
["mload", "len_pos"],
[
"mstore", i_placeholder,
["add", "len_pos", ["ceil32", "len_value"]]
],
],
],
]]
# loop from end of dynamic section to start of dynamic section,
# pushing each element onto the stack.
push_args += [
["label", start_label],
[
"if", ["lt", ["mload", i_placeholder], static_pos],
["goto", end_label]
],
["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))]
elif sig.args:
raise StructureException(
f"Wrong number of args for: {sig.name} (0 args given, expected {len(sig.args)})",
stmt_expr,
)
# Jump to function label.
jump_to_func = [
["add", ["pc"], 6], # set callback pointer.
["goto", f"priv_{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, ByteArrayLike):
dynamic_offsets = [(0, sig.output_type)]
pop_return_values = [
["pop", "pass"],
]
elif isinstance(sig.output_type, TupleLike):
static_offset = 0
pop_return_values = []
for name, typ in sig.output_type.tuple_items():
if isinstance(typ, ByteArrayLike):
pop_return_values.append([
"mstore",
["add", output_placeholder, static_offset], "pass"
])
dynamic_offsets.append(([
"mload",
["add", output_placeholder, static_offset]
], name))
static_offset += 32
else:
member_output_size = get_size_of_type(typ) * 32
pop_return_values.extend([[
"mstore", ["add", output_placeholder, pos], "pass"
] for pos in range(static_offset, static_offset +
member_output_size, 32)])
static_offset += member_output_size
# append dynamic unpacker.
dyn_idx = 0
for in_memory_offset, _out_type in dynamic_offsets:
ident = f"{stmt_expr.lineno}_{stmt_expr.col_offset}_arg_{dyn_idx}"
dyn_idx += 1
start_label = "dyn_unpack_start_" + ident
end_label = "dyn_unpack_end_" + ident
i_placeholder = context.new_internal_variable(
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],
[ # break
"if",
[
"ge", ["mload", i_placeholder],
["ceil32", ["mload", begin_pos]]
],
["goto", end_label],
],
[ # pop into correct memory slot.
"mstore",
[
"add", ["add", begin_pos, 32],
["mload", i_placeholder]
],
"pass",
],
# increment i
[
"mstore", i_placeholder,
["add", 32, ["mload", i_placeholder]]
],
["goto", start_label],
["label", end_label],
],
typ=None,
annotation="dynamic unpacker",
pos=getpos(stmt_expr),
)
pop_return_values.append(o)
call_body = list(
itertools.chain(
["seq_unchecked"],
pre_init,
push_local_vars,
push_args,
jump_to_func,
pop_return_values,
pop_local_vars,
[returner],
))
# If we have no return, we need to pop off
pop_returner_call_body = ["pop", call_body
] if sig.output_type is None else call_body
o = LLLnode.from_list(
pop_returner_call_body,
typ=sig.output_type,
location="memory",
pos=getpos(stmt_expr),
annotation=f"Internal Call: {method_name}",
add_gas_estimate=sig.gas,
)
o.gas += sig.gas
return o
def parse_external_function(
code: vy_ast.FunctionDef,
sig: FunctionSignature,
context: Context,
check_nonpayable: bool,
) -> LLLnode:
"""
Parse a external function (FuncDef), and produce full function body.
:param sig: the FuntionSignature
:param code: ast of function
:param check_nonpayable: if True, include a check that `msg.value == 0`
at the beginning of the function
:return: full sig compare & function body
"""
func_type = code._metadata["type"]
# Get nonreentrant lock
nonreentrant_pre, nonreentrant_post = get_nonreentrant_lock(func_type)
clampers = []
# Generate copiers
copier: List[Any] = ["pass"]
if not len(sig.base_args):
copier = ["pass"]
elif sig.name == "__init__":
copier = [
"codecopy", MemoryPositions.RESERVED_MEMORY, "~codelen",
sig.base_copy_size
]
context.memory_allocator.expand_memory(sig.max_copy_size)
clampers.append(copier)
if check_nonpayable and sig.mutability != "payable":
# if the contract contains payable functions, but this is not one of them
# add an assertion that the value of the call is zero
clampers.append(["assert", ["iszero", "callvalue"]])
# Fill variable positions
default_args_start_pos = len(sig.base_args)
for i, arg in enumerate(sig.args):
if i < len(sig.base_args):
clampers.append(
make_arg_clamper(
arg.pos,
context.memory_allocator.get_next_memory_position(),
arg.typ,
sig.name == "__init__",
))
if isinstance(arg.typ, ByteArrayLike):
mem_pos = context.memory_allocator.expand_memory(
32 * get_size_of_type(arg.typ))
context.vars[arg.name] = VariableRecord(arg.name, mem_pos, arg.typ,
False)
else:
if sig.name == "__init__":
context.vars[arg.name] = VariableRecord(
arg.name,
MemoryPositions.RESERVED_MEMORY + arg.pos,
arg.typ,
False,
)
elif i >= default_args_start_pos: # default args need to be allocated in memory.
type_size = get_size_of_type(arg.typ) * 32
default_arg_pos = context.memory_allocator.expand_memory(
type_size)
context.vars[arg.name] = VariableRecord(
name=arg.name,
pos=default_arg_pos,
typ=arg.typ,
mutable=False,
)
else:
context.vars[arg.name] = VariableRecord(name=arg.name,
pos=4 + arg.pos,
typ=arg.typ,
mutable=False,
location="calldata")
# Create "clampers" (input well-formedness checkers)
# Return function body
if sig.name == "__init__":
o = LLLnode.from_list(
["seq"] + clampers +
[parse_body(code.body, context)], # type: ignore
pos=getpos(code),
)
# Is default function.
elif sig.is_default_func():
o = LLLnode.from_list(
["seq"] + clampers + [parse_body(code.body, context)] +
[["stop"]], # type: ignore
pos=getpos(code),
)
# Is a normal function.
else:
# Function with default parameters.
if sig.total_default_args > 0:
function_routine = f"{sig.name}_{sig.method_id}"
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, _ = 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}
base_arg_names = {arg.name for arg in sig.base_args}
copier_arg_count = len(default_sig.args) - len(sig.base_args)
copier_arg_names = list(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: 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 default parameters from calldata.
for arg_name in copier_arg_names:
var = context.vars[arg_name]
calldata_offset = calldata_offset_map[arg_name]
# Add clampers.
default_copiers.append(
make_arg_clamper(
calldata_offset - 4,
var.pos,
var.typ,
))
# Add copying code.
_offset: Union[int, List[Any]] = calldata_offset
if isinstance(var.typ, ByteArrayLike):
_offset = [
"add", 4, ["calldataload", calldata_offset]
]
default_copiers.append(
get_external_arg_copier(
memory_dest=var.pos,
total_size=var.size * 32,
offset=_offset,
))
default_copiers.append(0) # for over arching seq, POP
sig_chain.append([
"if",
sig_compare,
[
"seq",
["seq"] + set_defaults if set_defaults else ["pass"],
["seq_unchecked"] +
default_copiers if default_copiers else ["pass"],
["goto", function_routine],
],
])
# Function with default parameters.
function_jump_label = f"{sig.name}_{sig.method_id}_skip"
o = LLLnode.from_list(
[
"seq",
sig_chain,
[
"seq",
["goto", function_jump_label],
["label", function_routine],
["seq"] + nonreentrant_pre + clampers +
[parse_body(c, context)
for c in code.body] + nonreentrant_post + [["stop"]],
["label", function_jump_label],
],
],
typ=None,
pos=getpos(code),
)
else:
# Function without default parameters.
sig_compare, _ = get_sig_statements(sig, getpos(code))
o = LLLnode.from_list(
[
"if",
sig_compare,
["seq"] + nonreentrant_pre + clampers +
[parse_body(c, context)
for c in code.body] + nonreentrant_post + [["stop"]],
],
typ=None,
pos=getpos(code),
)
return o
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 using make_setter, since
# our memory encoding happens to be identical to the ABI
# encoding.
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)
def make_arg_clamper(datapos, mempos, typ, is_init=False):
"""
Clamps argument to type limits.
Arguments
---------
datapos : int | LLLnode
Calldata offset of the value being clamped
mempos : int | LLLnode
Memory offset that the value is stored at during clamping
typ : vyper.types.types.BaseType
Type of the value
is_init : bool, optional
Boolean indicating if we are generating init bytecode
Returns
-------
LLLnode
Arg clamper LLL
"""
if not is_init:
data_decl = ["calldataload", ["add", 4, datapos]]
copier = functools.partial(_mk_calldatacopy_copier, mempos=mempos)
else:
data_decl = ["codeload", ["add", "~codelen", datapos]]
copier = functools.partial(_mk_codecopy_copier, mempos=mempos)
# Numbers: make sure they're in range
if is_base_type(typ, "int128"):
return LLLnode.from_list(int128_clamp(data_decl),
typ=typ,
annotation="checking int128 input")
# Booleans: make sure they're zero or one
elif is_base_type(typ, "bool"):
if version_check(begin="constantinople"):
lll = ["assert", ["iszero", ["shr", 1, data_decl]]]
else:
lll = ["uclamplt", data_decl, 2]
return LLLnode.from_list(lll,
typ=typ,
annotation="checking bool input")
# Addresses: make sure they're in range
elif is_base_type(typ, "address"):
return LLLnode.from_list(address_clamp(data_decl),
typ=typ,
annotation="checking address input")
# Bytes: make sure they have the right size
elif isinstance(typ, ByteArrayLike):
return LLLnode.from_list(
[
"seq",
copier(data_decl, 32 + typ.maxlen),
[
"assert",
[
"le", ["calldataload", ["add", 4, data_decl]],
typ.maxlen
]
],
],
typ=None,
annotation="checking bytearray input",
)
# Lists: recurse
elif isinstance(typ, ListType):
if typ.count > 5 or (type(datapos) is list and type(mempos) is list):
# find ultimate base type
subtype = typ.subtype
while hasattr(subtype, "subtype"):
subtype = subtype.subtype
# make arg clamper for the base type
offset = MemoryPositions.FREE_LOOP_INDEX
clamper = make_arg_clamper(
["add", datapos, ["mload", offset]],
["add", mempos, ["mload", offset]],
subtype,
is_init,
)
if clamper.value == "pass":
# no point looping if the base type doesn't require clamping
return clamper
# loop the entire array at once, even if it's multidimensional
type_size = get_size_of_type(typ)
i_incr = get_size_of_type(subtype) * 32
mem_to = type_size * 32
loop_label = f"_check_list_loop_{str(uuid.uuid4())}"
lll_node = [
["mstore", offset, 0], # init loop
["label", loop_label],
clamper,
["mstore", offset, ["add", ["mload", offset], i_incr]],
[
"if", ["lt", ["mload", offset], mem_to],
["goto", loop_label]
],
]
else:
lll_node = []
for i in range(typ.count):
offset = get_size_of_type(typ.subtype) * 32 * i
lll_node.append(
make_arg_clamper(datapos + offset, mempos + offset,
typ.subtype, is_init))
return LLLnode.from_list(["seq"] + lll_node,
typ=None,
annotation="checking list input")
# Otherwise don't make any checks
else:
return LLLnode.from_list("pass")
def init_func_init_lll():
return LLLnode.from_list(["seq"] + LIMIT_MEMORY_SET, typ=None)
def pack_arguments(signature, args, context, stmt_expr, is_external_call):
pos = getpos(stmt_expr)
setters = []
staticarray_offset = 0
maxlen = sum([get_size_of_type(arg.typ) for arg in signature.args]) * 32
if is_external_call:
maxlen += 32
placeholder_typ = ByteArrayType(maxlen=maxlen)
placeholder = context.new_internal_variable(placeholder_typ)
if is_external_call:
setters.append(["mstore", placeholder, signature.method_id])
placeholder += 32
if len(signature.args) != len(args):
return
# check for dynamic-length types
dynamic_remaining = len(
[i for i in signature.args if isinstance(i.typ, ByteArrayLike)])
needpos = bool(dynamic_remaining)
for i, (arg,
typ) in enumerate(zip(args, [arg.typ for arg in signature.args])):
if isinstance(typ, BaseType):
setters.append(
make_setter(
LLLnode.from_list(
placeholder + staticarray_offset + i * 32,
typ=typ,
),
arg,
"memory",
pos=pos,
in_function_call=True,
))
elif isinstance(typ, ByteArrayLike):
dynamic_remaining -= 1
setters.append(
["mstore", placeholder + staticarray_offset + i * 32, "_poz"])
arg_copy = LLLnode.from_list("_s",
typ=arg.typ,
location=arg.location)
target = LLLnode.from_list(
["add", placeholder, "_poz"],
typ=typ,
location="memory",
)
pos_setter = "pass"
# if `arg.value` is None, this is a call to `empty()`
# if `arg.typ.maxlen` is 0, this is a literal "" or b""
if arg.value is None or arg.typ.maxlen == 0:
if dynamic_remaining:
# only adjust the dynamic pointer if this is not the last dynamic type
pos_setter = ["set", "_poz", ["add", "_poz", 64]]
setters.append(["seq", mzero(target, 64), pos_setter])
else:
if dynamic_remaining:
pos_setter = [
"set",
"_poz",
[
"add", 32,
["ceil32", ["add", "_poz",
get_length(arg_copy)]]
],
]
setters.append([
"with",
"_s",
arg,
[
"seq",
make_byte_array_copier(target, arg_copy, pos),
pos_setter
],
])
elif isinstance(typ, (StructType, ListType)):
if has_dynamic_data(typ):
return
target = LLLnode.from_list(
[placeholder + staticarray_offset + i * 32],
typ=typ,
location="memory",
)
setters.append(make_setter(target, arg, "memory", pos=pos))
staticarray_offset += 32 * (get_size_of_type(typ) - 1)
else:
return
if is_external_call:
returner = [[placeholder - 4]]
inargsize = placeholder_typ.maxlen - 28
else:
# internal call does not use a returner or adjust max length for signature
returner = []
inargsize = placeholder_typ.maxlen
if needpos:
return (
LLLnode.from_list(
[
"with", "_poz",
len(args) * 32 + staticarray_offset,
["seq"] + setters + returner
],
typ=placeholder_typ,
location="memory",
),
inargsize,
placeholder,
)
else:
return (
LLLnode.from_list(["seq"] + setters + returner,
typ=placeholder_typ,
location="memory"),
inargsize,
placeholder,
)
def pack_logging_data(arg_nodes, arg_types, context, pos):
# Checks to see if there's any data
if not arg_nodes:
return ["seq"], 0, None, 0
holder = ["seq"]
maxlen = len(arg_nodes) * 32 # total size of all packed args (upper limit)
# Unroll any function calls, to temp variables.
prealloacted = {}
for idx, node in enumerate(arg_nodes):
if isinstance(
node,
(vy_ast.Str, vy_ast.Call)) and node.get("func.id") != "empty":
expr = Expr(node, context)
source_lll = expr.lll_node
tmp_variable = context.new_internal_variable(source_lll.typ)
tmp_variable_node = LLLnode.from_list(
tmp_variable,
typ=source_lll.typ,
pos=getpos(node),
location="memory",
annotation=f"log_prealloacted {source_lll.typ}",
)
# Copy bytes.
holder.append(
make_setter(tmp_variable_node,
source_lll,
pos=getpos(node),
location="memory"))
prealloacted[idx] = tmp_variable_node
# Create internal variables for for dynamic and static args.
static_types = []
for typ in arg_types:
static_types.append(
typ if not typ.is_dynamic_size else Uint256Definition())
requires_dynamic_offset = any(typ.is_dynamic_size for typ in arg_types)
dynamic_offset_counter = None
if requires_dynamic_offset:
# TODO refactor out old type objects
dynamic_offset_counter = context.new_internal_variable(BaseType(32))
dynamic_placeholder = context.new_internal_variable(BaseType(32))
static_vars = [context.new_internal_variable(i) for i in static_types]
# Populate static placeholders.
for i, (node, typ) in enumerate(zip(arg_nodes, arg_types)):
placeholder = static_vars[i]
if not isinstance(typ, ArrayValueAbstractType):
holder, maxlen = pack_args_by_32(
holder,
maxlen,
prealloacted.get(i, node),
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 typ in arg_types:
if typ.is_dynamic_size:
maxlen += typ.size_in_bytes
if requires_dynamic_offset:
datamem_start = dynamic_placeholder + 32
else:
datamem_start = static_vars[0]
# Copy necessary data into allocated dynamic section.
for i, (node, typ) in enumerate(zip(arg_nodes, arg_types)):
if isinstance(typ, ArrayValueAbstractType):
if isinstance(node,
vy_ast.Call) and node.func.get("id") == "empty":
# TODO add support for this
raise StructureException(
"Cannot use `empty` on Bytes or String types within an event log",
node)
pack_args_by_32(
holder=holder,
maxlen=maxlen,
arg=prealloacted.get(i, node),
typ=typ,
context=context,
placeholder=static_vars[i],
datamem_start=datamem_start,
dynamic_offset_counter=dynamic_offset_counter,
pos=pos,
)
return holder, maxlen, dynamic_offset_counter, datamem_start
def external_call(node,
context,
interface_name,
contract_address,
pos,
value=None,
gas=None):
from vyper.old_codegen.expr import Expr
if value is None:
value = 0
if gas is None:
gas = "gas"
method_name = node.func.attr
sig = context.sigs[interface_name][method_name]
inargs, inargsize, _ = pack_arguments(
sig,
[Expr(arg, context).lll_node for arg in node.args],
context,
node.func,
is_external_call=True,
)
output_placeholder, output_size, returner = get_external_call_output(
sig, context)
sub = ["seq"]
if not output_size:
# if we do not expect return data, check that a contract exists at the target address
# we can omit this when we _do_ expect return data because we later check `returndatasize`
sub.append(["assert", ["extcodesize", contract_address]])
if context.is_constant() and sig.mutability not in ("view", "pure"):
# TODO this can probably go
raise StateAccessViolation(
f"May not call state modifying function '{method_name}' "
f"within {context.pp_constancy()}.",
node,
)
if context.is_constant() or sig.mutability in ("view", "pure"):
sub.append([
"assert",
[
"staticcall",
gas,
contract_address,
inargs,
inargsize,
output_placeholder,
output_size,
],
])
else:
sub.append([
"assert",
[
"call",
gas,
contract_address,
value,
inargs,
inargsize,
output_placeholder,
output_size,
],
])
if output_size:
# when return data is expected, revert when the length of `returndatasize` is insufficient
output_type = sig.output_type
if not has_dynamic_data(output_type):
static_output_size = get_static_size_of_type(output_type) * 32
sub.append(
["assert", ["gt", "returndatasize", static_output_size - 1]])
else:
if isinstance(output_type, ByteArrayLike):
types_list = (output_type, )
elif isinstance(output_type, TupleLike):
types_list = output_type.tuple_members()
else:
raise
dynamic_checks = []
static_offset = output_placeholder
static_output_size = 0
for typ in types_list:
# ensure length of bytes does not exceed max allowable length for type
if isinstance(typ, ByteArrayLike):
static_output_size += 32
# do not perform this check on calls to a JSON interface - we don't know
# for certain how long the expected data is
if not sig.is_from_json:
dynamic_checks.append([
"assert",
[
"lt",
[
"mload",
[
"add", ["mload", static_offset],
output_placeholder
],
],
typ.maxlen + 1,
],
])
static_offset += get_static_size_of_type(typ) * 32
static_output_size += get_static_size_of_type(typ) * 32
sub.append(
["assert", ["gt", "returndatasize", static_output_size - 1]])
sub.extend(dynamic_checks)
sub.extend(returner)
return LLLnode.from_list(sub,
typ=sig.output_type,
location="memory",
pos=getpos(node))
def pack_args_by_32(
holder,
maxlen,
arg,
typ,
context,
placeholder,
dynamic_offset_counter=None,
datamem_start=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 typ.size_in_bytes == 32:
if isinstance(arg, LLLnode):
value = unwrap_location(arg)
else:
value = Expr(arg, context).lll_node
value = unwrap_location(value)
holder.append(
LLLnode.from_list(["mstore", placeholder, value],
location="memory"))
elif isinstance(typ, ArrayValueAbstractType):
if isinstance(arg, LLLnode): # Is prealloacted variable.
source_lll = arg
else:
source_lll = Expr(arg, context).lll_node
# Set static offset, in arg slot.
holder.append(
LLLnode.from_list(
["mstore", placeholder, ["mload", dynamic_offset_counter]]))
# Get the beginning to write the ByteArray to.
# TODO refactor out the use of `ByteArrayLike` once old types are removed from parser
dest_placeholder = LLLnode.from_list(
["add", datamem_start, ["mload", dynamic_offset_counter]],
typ=ByteArrayLike(typ.length),
location="memory",
annotation="pack_args_by_32:dest_placeholder",
)
copier = make_byte_array_copier(dest_placeholder, source_lll, pos=pos)
holder.append(copier)
# Add zero padding.
holder.append(zero_pad(dest_placeholder))
# Increment offset counter.
increment_counter = LLLnode.from_list(
[
"mstore",
dynamic_offset_counter,
[
"add",
[
"add",
["mload", dynamic_offset_counter],
["ceil32", ["mload", dest_placeholder]],
],
32,
],
],
annotation="Increment dynamic offset counter",
)
holder.append(increment_counter)
elif isinstance(typ, ArrayDefinition):
if isinstance(arg, vy_ast.Call) and arg.func.get("id") == "empty":
# special case for `empty()` with a static-sized array
holder.append(mzero(placeholder, typ.size_in_bytes))
maxlen += typ.size_in_bytes - 32
return holder, maxlen
maxlen += (typ.length - 1) * 32
typ = typ.value_type
# NOTE: Below code could be refactored into iterators/getter functions for each type of
# repetitive loop. But seeing how each one is a unique for loop, and in which way
# the sub value makes the difference in each type of list clearer.
# List from storage
if isinstance(arg, vy_ast.Attribute) and arg.value.id == "self":
stor_list = context.globals[arg.attr]
size = stor_list.typ.count
mem_offset = 0
for i in range(0, size):
storage_offset = i
arg2 = LLLnode.from_list([
"sload",
["add", Expr(arg, context).lll_node, storage_offset]
], )
holder, maxlen = pack_args_by_32(
holder,
maxlen,
arg2,
typ,
context,
placeholder + mem_offset,
pos=pos,
)
mem_offset += typ.size_in_bytes
# List from variable.
elif isinstance(arg, vy_ast.Name):
size = context.vars[arg.id].size
pos = context.vars[arg.id].pos
mem_offset = 0
for _ in range(0, size):
arg2 = LLLnode.from_list(
pos + mem_offset, location=context.vars[arg.id].location)
holder, maxlen = pack_args_by_32(
holder,
maxlen,
arg2,
typ,
context,
placeholder + mem_offset,
pos=pos,
)
mem_offset += typ.size_in_bytes
# List from list literal.
else:
mem_offset = 0
for arg2 in arg.elements:
holder, maxlen = pack_args_by_32(
holder,
maxlen,
arg2,
typ,
context,
placeholder + mem_offset,
pos=pos,
)
mem_offset += typ.size_in_bytes
return holder, maxlen
def make_byte_array_copier(destination, source, pos=None):
if not isinstance(source.typ, ByteArrayLike):
btype = "byte array" if isinstance(destination.typ,
ByteArrayType) else "string"
raise TypeMismatch(f"Can only set a {btype} to another {btype}", pos)
if isinstance(
source.typ,
ByteArrayLike) and source.typ.maxlen > destination.typ.maxlen:
raise TypeMismatch(
f"Cannot cast from greater max-length {source.typ.maxlen} to shorter "
f"max-length {destination.typ.maxlen}")
# stricter check for zeroing a byte array.
if isinstance(source.typ, ByteArrayLike):
if source.value is None and source.typ.maxlen != destination.typ.maxlen:
raise TypeMismatch(
f"Bad type for clearing bytes: expected {destination.typ}"
f" but got {source.typ}")
# Special case: memory to memory
if source.location == "memory" and destination.location == "memory":
gas_calculation = GAS_IDENTITY + GAS_IDENTITYWORD * (
ceil32(source.typ.maxlen) // 32)
o = LLLnode.from_list(
[
"with",
"_source",
source,
[
"with",
"_sz",
["add", 32, ["mload", "_source"]],
[
"assert",
[
"call", ["gas"], 4, 0, "_source", "_sz",
destination, "_sz"
]
],
],
], # noqa: E501
typ=None,
add_gas_estimate=gas_calculation,
annotation="Memory copy",
)
return o
if source.value is None:
pos_node = source
else:
pos_node = LLLnode.from_list("_pos",
typ=source.typ,
location=source.location)
# Get the length
if source.value is None:
length = 1
elif source.location == "memory":
length = ["add", ["mload", "_pos"], 32]
elif source.location == "storage":
length = ["add", ["sload", "_pos"], 32]
pos_node = LLLnode.from_list(
pos_node,
typ=source.typ,
location=source.location,
)
else:
raise CompilerPanic(f"Unsupported location: {source.location}")
if destination.location == "storage":
destination = LLLnode.from_list(
destination,
typ=destination.typ,
location=destination.location,
)
# Maximum theoretical length
max_length = 32 if source.value is None else source.typ.maxlen + 32
return LLLnode.from_list(
[
"with",
"_pos",
0 if source.value is None else source,
make_byte_slice_copier(
destination, pos_node, length, max_length, pos=pos),
],
typ=None,
)
def make_byte_slice_copier(destination, source, length, max_length, pos=None):
# Special case: memory to memory
if source.location == "memory" and destination.location == "memory":
return LLLnode.from_list(
[
"with",
"_l",
max_length,
[
"pop",
["call", ["gas"], 4, 0, source, "_l", destination, "_l"]
],
],
typ=None,
annotation=f"copy byte slice dest: {str(destination)}",
)
# special case: rhs is zero
if source.value is None:
if destination.location == "memory":
return mzero(destination, max_length)
else:
loader = 0
# Copy over data
elif source.location == "memory":
loader = [
"mload",
[
"add", "_pos",
["mul", 32, ["mload", MemoryPositions.FREE_LOOP_INDEX]]
]
]
elif source.location == "storage":
loader = [
"sload",
["add", "_pos", ["mload", MemoryPositions.FREE_LOOP_INDEX]]
]
elif source.location == "calldata":
loader = [
"calldataload",
[
"add", "_pos",
["mul", 32, ["mload", MemoryPositions.FREE_LOOP_INDEX]]
],
]
else:
raise CompilerPanic(f"Unsupported location: {source.location}")
# Where to paste it?
if destination.location == "memory":
setter = [
"mstore",
[
"add", "_opos",
["mul", 32, ["mload", MemoryPositions.FREE_LOOP_INDEX]]
],
loader,
]
elif destination.location == "storage":
setter = [
"sstore",
["add", "_opos", ["mload", MemoryPositions.FREE_LOOP_INDEX]],
loader
]
else:
raise CompilerPanic(f"Unsupported location: {destination.location}")
# Check to see if we hit the length
checker = [
"if",
[
"gt", ["mul", 32, ["mload", MemoryPositions.FREE_LOOP_INDEX]],
"_actual_len"
],
"break",
]
# Make a loop to do the copying
ipos = 0 if source.value is None else source
o = [
"with",
"_pos",
ipos,
[
"with",
"_opos",
destination,
[
"with",
"_actual_len",
length,
[
"repeat",
MemoryPositions.FREE_LOOP_INDEX,
0,
(max_length + 31) // 32,
["seq", checker, setter],
],
],
],
]
return LLLnode.from_list(
o,
typ=None,
annotation=f"copy byte slice src: {source} dst: {destination}",
pos=pos,
)
def parse_internal_function(code: vy_ast.FunctionDef, sig: FunctionSignature,
context: Context) -> LLLnode:
"""
Parse a internal function (FuncDef), and produce full function body.
:param sig: the FuntionSignature
:param code: ast of function
:return: full sig compare & function body
"""
func_type = code._metadata["type"]
# Get nonreentrant lock
nonreentrant_pre, nonreentrant_post = get_nonreentrant_lock(func_type)
# Create callback_ptr, this stores a destination in the bytecode for a internal
# function to jump to after a function has executed.
clampers: List[LLLnode] = []
# Allocate variable space.
context.memory_allocator.expand_memory(sig.max_copy_size)
_post_callback_ptr = f"{sig.name}_{sig.method_id}_post_callback_ptr"
context.callback_ptr = context.new_internal_variable(
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]))
# internal 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_internal_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.expand_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,
)
# internal function copiers. No clamping for internal 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_internal_variable(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 internal_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, internal_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 internal,
# 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_internal_arg_copier(
memory_dest=var.pos,
total_size=_size,
))
# Unpack byte array if necessary.
if dynamics:
i_placeholder = context.new_internal_variable(
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",
internal_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 internal functions all variable loading occurs in the default
# function sub routine.
_clampers = [["label", _post_callback_ptr]]
# Function with default parameters.
return LLLnode.from_list(
[
"seq",
sig_chain,
["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, internal_label = get_sig_statements(sig, getpos(code))
return LLLnode.from_list(
["seq"] + [internal_label] + nonreentrant_pre + clampers +
[parse_body(c, context)
for c in code.body] + nonreentrant_post + stop_func,
typ=None,
pos=getpos(code),
)
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)