/*
This file is part of solidity.
solidity is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
solidity is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with solidity. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @author Christian <chris@ethereum.org>
* @date 2017
* Routines that generate JULIA code related to ABI encoding, decoding and type conversions.
*/
#include <libsolidity/codegen/ABIFunctions.h>
#include <libdevcore/Whiskers.h>
#include <libsolidity/ast/AST.h>
using namespace std;
using namespace dev;
using namespace dev::solidity;
string ABIFunctions::tupleEncoder(
TypePointers const& _givenTypes,
TypePointers const& _targetTypes,
bool _encodeAsLibraryTypes
)
{
string functionName = string("abi_encode_tuple_");
for (auto const& t: _givenTypes)
functionName += t->identifier() + "_";
functionName += "_to_";
for (auto const& t: _targetTypes)
functionName += t->identifier() + "_";
if (_encodeAsLibraryTypes)
functionName += "_library";
return createFunction(functionName, [&]() {
solAssert(!_givenTypes.empty(), "");
// Note that the values are in reverse due to the difference in calling semantics.
Whiskers templ(R"(
function <functionName>(headStart <valueParams>) -> tail {
tail := add(headStart, <headSize>)
<encodeElements>
}
)");
templ("functionName", functionName);
size_t const headSize_ = headSize(_targetTypes);
templ("headSize", to_string(headSize_));
string valueParams;
string encodeElements;
size_t headPos = 0;
size_t stackPos = 0;
for (size_t i = 0; i < _givenTypes.size(); ++i)
{
solAssert(_givenTypes[i], "");
solAssert(_targetTypes[i], "");
size_t sizeOnStack = _givenTypes[i]->sizeOnStack();
string valueNames = "";
for (size_t j = 0; j < sizeOnStack; j++)
{
valueNames += "value" + to_string(stackPos) + ", ";
valueParams = ", value" + to_string(stackPos) + valueParams;
stackPos++;
}
bool dynamic = _targetTypes[i]->isDynamicallyEncoded();
Whiskers elementTempl(
dynamic ?
string(R"(
mstore(add(headStart, <pos>), sub(tail, headStart))
tail := <abiEncode>(<values> tail)
)") :
string(R"(
<abiEncode>(<values> add(headStart, <pos>))
)")
);
elementTempl("values", valueNames);
elementTempl("pos", to_string(headPos));
elementTempl("abiEncode", abiEncodingFunction(*_givenTypes[i], *_targetTypes[i], _encodeAsLibraryTypes, false));
encodeElements += elementTempl.render();
headPos += dynamic ? 0x20 : _targetTypes[i]->calldataEncodedSize();
}
solAssert(headPos == headSize_, "");
templ("valueParams", valueParams);
templ("encodeElements", encodeElements);
return templ.render();
});
}
string ABIFunctions::requestedFunctions()
{
string result;
for (auto const& f: m_requestedFunctions)
result += f.second;
m_requestedFunctions.clear();
return result;
}
string ABIFunctions::cleanupFunction(Type const& _type, bool _revertOnFailure)
{
string functionName = string("cleanup_") + (_revertOnFailure ? "revert_" : "assert_") + _type.identifier();
return createFunction(functionName, [&]() {
Whiskers templ(R"(
function <functionName>(value) -> cleaned {
<body>
}
)");
templ("functionName", functionName);
switch (_type.category())
{
case Type::Category::Integer:
{
IntegerType const& type = dynamic_cast<IntegerType const&>(_type);
if (type.numBits() == 256)
templ("body", "cleaned := value");
else if (type.isSigned())
templ("body", "cleaned := signextend(" + to_string(type.numBits() / 8 - 1) + ", value)");
else
templ("body", "cleaned := and(value, " + toCompactHexWithPrefix((u256(1) << type.numBits()) - 1) + ")");
break;
}
case Type::Category::RationalNumber:
templ("body", "cleaned := value");
break;
case Type::Category::Bool:
templ("body", "cleaned := iszero(iszero(value))");
break;
case Type::Category::FixedPoint:
solUnimplemented("Fixed point types not implemented.");
break;
case Type::Category::Array:
solAssert(false, "Array cleanup requested.");
break;
case Type::Category::Struct:
solAssert(false, "Struct cleanup requested.");
break;
case Type::Category::FixedBytes:
{
FixedBytesType const& type = dynamic_cast<FixedBytesType const&>(_type);
if (type.numBytes() == 32)
templ("body", "cleaned := value");
else if (type.numBytes() == 0)
templ("body", "cleaned := 0");
else
{
size_t numBits = type.numBytes() * 8;
u256 mask = ((u256(1) << numBits) - 1) << (256 - numBits);
templ("body", "cleaned := and(value, " + toCompactHexWithPrefix(mask) + ")");
}
break;
}
case Type::Category::Contract:
templ("body", "cleaned := " + cleanupFunction(IntegerType(160, IntegerType::Modifier::Address)) + "(value)");
break;
case Type::Category::Enum:
{
size_t members = dynamic_cast<EnumType const&>(_type).numberOfMembers();
solAssert(members > 0, "empty enum should have caused a parser error.");
Whiskers w("switch lt(value, <members>) case 0 { <failure> } cleaned := value");
w("members", to_string(members));
if (_revertOnFailure)
w("failure", "revert(0, 0)");
else
w("failure", "invalid()");
templ("body", w.render());
break;
}
default:
solAssert(false, "Cleanup of type " + _type.identifier() + " requested.");
}
return templ.render();
});
}
string ABIFunctions::conversionFunction(Type const& _from, Type const& _to)
{
string functionName =
"convert_" +
_from.identifier() +
"_to_" +
_to.identifier();
return createFunction(functionName, [&]() {
Whiskers templ(R"(
function <functionName>(value) -> converted {
<body>
}
)");
templ("functionName", functionName);
string body;
auto toCategory = _to.category();
auto fromCategory = _from.category();
switch (fromCategory)
{
case Type::Category::Integer:
case Type::Category::RationalNumber:
case Type::Category::Contract:
{
if (RationalNumberType const* rational = dynamic_cast<RationalNumberType const*>(&_from))
solUnimplementedAssert(!rational->isFractional(), "Not yet implemented - FixedPointType.");
if (toCategory == Type::Category::FixedBytes)
{
solAssert(
fromCategory == Type::Category::Integer || fromCategory == Type::Category::RationalNumber,
"Invalid conversion to FixedBytesType requested."
);
FixedBytesType const& toBytesType = dynamic_cast<FixedBytesType const&>(_to);
body =
Whiskers("converted := <shiftLeft>(<clean>(value))")
("shiftLeft", shiftLeftFunction(256 - toBytesType.numBytes() * 8))
("clean", cleanupFunction(_from))
.render();
}
else if (toCategory == Type::Category::Enum)
{
solAssert(_from.mobileType(), "");
body =
Whiskers("converted := <cleanEnum>(<cleanInt>(value))")
("cleanEnum", cleanupFunction(_to, false))
// "mobileType()" returns integer type for rational
("cleanInt", cleanupFunction(*_from.mobileType()))
.render();
}
else if (toCategory == Type::Category::FixedPoint)
{
solUnimplemented("Not yet implemented - FixedPointType.");
}
else
{
solAssert(
toCategory == Type::Category::Integer ||
toCategory == Type::Category::Contract,
"");
IntegerType const addressType(160, IntegerType::Modifier::Address);
IntegerType const& to =
toCategory == Type::Category::Integer ?
dynamic_cast<IntegerType const&>(_to) :
addressType;
// Clean according to the "to" type, except if this is
// a widening conversion.
IntegerType const* cleanupType = &to;
if (fromCategory != Type::Category::RationalNumber)
{
IntegerType const& from =
fromCategory == Type::Category::Integer ?
dynamic_cast<IntegerType const&>(_from) :
addressType;
if (to.numBits() > from.numBits())
cleanupType = &from;
}
body =
Whiskers("converted := <cleanInt>(value)")
("cleanInt", cleanupFunction(*cleanupType))
.render();
}
break;
}
case Type::Category::Bool:
{
solAssert(_from == _to, "Invalid conversion for bool.");
body =
Whiskers("converted := <clean>(value)")
("clean", cleanupFunction(_from))
.render();
break;
}
case Type::Category::FixedPoint:
solUnimplemented("Fixed point types not implemented.");
break;
case Type::Category::Array:
solUnimplementedAssert(false, "Array conversion not implemented.");
break;
case Type::Category::Struct:
solUnimplementedAssert(false, "Struct conversion not implemented.");
break;
case Type::Category::FixedBytes:
{
FixedBytesType const& from = dynamic_cast<FixedBytesType const&>(_from);
if (toCategory == Type::Category::Integer)
body =
Whiskers("converted := <convert>(<shift>(value))")
("shift", shiftRightFunction(256 - from.numBytes() * 8, false))
("convert", conversionFunction(IntegerType(from.numBytes() * 8), _to))
.render();
else
{
// clear for conversion to longer bytes
solAssert(toCategory == Type::Category::FixedBytes, "Invalid type conversion requested.");
body =
Whiskers("converted := <clean>(value)")
("clean", cleanupFunction(from))
.render();
}
break;
}
case Type::Category::Function:
{
solAssert(false, "Conversion should not be called for function types.");
break;
}
case Type::Category::Enum:
{
solAssert(toCategory == Type::Category::Integer || _from == _to, "");
EnumType const& enumType = dynamic_cast<decltype(enumType)>(_from);
body =
Whiskers("converted := <clean>(value)")
("clean", cleanupFunction(enumType))
.render();
break;
}
case Type::Category::Tuple:
{
solUnimplementedAssert(false, "Tuple conversion not implemented.");
break;
}
default:
solAssert(false, "");
}
solAssert(!body.empty(), "");
templ("body", body);
return templ.render();
});
}
string ABIFunctions::cleanupCombinedExternalFunctionIdFunction()
{
string functionName = "cleanup_combined_external_function_id";
return createFunction(functionName, [&]() {
return Whiskers(R"(
function <functionName>(addr_and_selector) -> cleaned {
cleaned := <clean>(addr_and_selector)
}
)")
("functionName", functionName)
("clean", cleanupFunction(FixedBytesType(24)))
.render();
});
}
string ABIFunctions::combineExternalFunctionIdFunction()
{
string functionName = "combine_external_function_id";
return createFunction(functionName, [&]() {
return Whiskers(R"(
function <functionName>(addr, selector) -> combined {
combined := <shl64>(or(<shl32>(addr), and(selector, 0xffffffff)))
}
)")
("functionName", functionName)
("shl32", shiftLeftFunction(32))
("shl64", shiftLeftFunction(64))
.render();
});
}
string ABIFunctions::abiEncodingFunction(
Type const& _from,
Type const& _to,
bool _encodeAsLibraryTypes,
bool _compacted
)
{
solUnimplementedAssert(
_to.mobileType() &&
_to.mobileType()->interfaceType(_encodeAsLibraryTypes) &&
_to.mobileType()->interfaceType(_encodeAsLibraryTypes)->encodingType(),
"Encoding type \"" + _to.toString() + "\" not yet implemented."
);
TypePointer toInterface = _to.mobileType()->interfaceType(_encodeAsLibraryTypes)->encodingType();
Type const& to = *toInterface;
if (_from.category() == Type::Category::StringLiteral)
return abiEncodingFunctionStringLiteral(_from, to, _encodeAsLibraryTypes);
else if (auto toArray = dynamic_cast<ArrayType const*>(&to))
{
solAssert(_from.category() == Type::Category::Array, "");
solAssert(to.dataStoredIn(DataLocation::Memory), "");
ArrayType const& fromArray = dynamic_cast<ArrayType const&>(_from);
if (fromArray.location() == DataLocation::CallData)
return abiEncodingFunctionCalldataArray(fromArray, *toArray, _encodeAsLibraryTypes);
else if (!fromArray.isByteArray() && (
fromArray.location() == DataLocation::Memory ||
fromArray.baseType()->storageBytes() > 16
))
return abiEncodingFunctionSimpleArray(fromArray, *toArray, _encodeAsLibraryTypes);
else if (fromArray.location() == DataLocation::Memory)
return abiEncodingFunctionMemoryByteArray(fromArray, *toArray, _encodeAsLibraryTypes);
else if (fromArray.location() == DataLocation::Storage)
return abiEncodingFunctionCompactStorageArray(fromArray, *toArray, _encodeAsLibraryTypes);
else
solAssert(false, "");
}
else if (auto const* toStruct = dynamic_cast<StructType const*>(&to))
{
StructType const* fromStruct = dynamic_cast<StructType const*>(&_from);
solAssert(fromStruct, "");
return abiEncodingFunctionStruct(*fromStruct, *toStruct, _encodeAsLibraryTypes);
}
else if (_from.category() == Type::Category::Function)
return abiEncodingFunctionFunctionType(
dynamic_cast<FunctionType const&>(_from),
to,
_encodeAsLibraryTypes,
_compacted
);
solAssert(_from.sizeOnStack() == 1, "");
solAssert(to.isValueType(), "");
solAssert(to.calldataEncodedSize() == 32, "");
string functionName =
"abi_encode_" +
_from.identifier() +
"_to_" +
to.identifier() +
(_encodeAsLibraryTypes ? "_library" : "");
return createFunction(functionName, [&]() {
solAssert(!to.isDynamicallyEncoded(), "");
Whiskers templ(R"(
function <functionName>(value, pos) {
mstore(pos, <cleanupConvert>)
}
)");
templ("functionName", functionName);
if (_from.dataStoredIn(DataLocation::Storage) && to.isValueType())
{
// special case: convert storage reference type to value type - this is only
// possible for library calls where we just forward the storage reference
solAssert(_encodeAsLibraryTypes, "");
solAssert(to == IntegerType(256), "");
templ("cleanupConvert", "value");
}
else
{
if (_from == to)
templ("cleanupConvert", cleanupFunction(_from) + "(value)");
else
templ("cleanupConvert", conversionFunction(_from, to) + "(value)");
}
return templ.render();
});
}
string ABIFunctions::abiEncodingFunctionCalldataArray(
Type const& _from,
Type const& _to,
bool _encodeAsLibraryTypes
)
{
solAssert(_to.isDynamicallySized(), "");
solAssert(_from.category() == Type::Category::Array, "Unknown dynamic type.");
solAssert(_to.category() == Type::Category::Array, "Unknown dynamic type.");
auto const& fromArrayType = dynamic_cast<ArrayType const&>(_from);
auto const& toArrayType = dynamic_cast<ArrayType const&>(_to);
solAssert(fromArrayType.location() == DataLocation::CallData, "");
solAssert(
*fromArrayType.copyForLocation(DataLocation::Memory, true) ==
*toArrayType.copyForLocation(DataLocation::Memory, true),
""
);
string functionName =
"abi_encode_" +
_from.identifier() +
"_to_" +
_to.identifier() +
(_encodeAsLibraryTypes ? "_library" : "");
return createFunction(functionName, [&]() {
solUnimplementedAssert(fromArrayType.isByteArray(), "");
// TODO if this is not a byte array, we might just copy byte-by-byte anyway,
// because the encoding is position-independent, but we have to check that.
Whiskers templ(R"(
function <functionName>(start, length, pos) -> end {
<storeLength> // might update pos
<copyFun>(start, pos, length)
end := add(pos, <roundUpFun>(length))
}
)");
templ("storeLength", _to.isDynamicallySized() ? "mstore(pos, length) pos := add(pos, 0x20)" : "");
templ("functionName", functionName);
templ("copyFun", copyToMemoryFunction(true));
templ("roundUpFun", roundUpFunction());
return templ.render();
});
}
string ABIFunctions::abiEncodingFunctionSimpleArray(
ArrayType const& _from,
ArrayType const& _to,
bool _encodeAsLibraryTypes
)
{
string functionName =
"abi_encode_" +
_from.identifier() +
"_to_" +
_to.identifier() +
(_encodeAsLibraryTypes ? "_library" : "");
solAssert(_from.isDynamicallySized() == _to.isDynamicallySized(), "");
solAssert(_from.length() == _to.length(), "");
solAssert(_from.dataStoredIn(DataLocation::Memory) || _from.dataStoredIn(DataLocation::Storage), "");
solAssert(!_from.isByteArray(), "");
solAssert(_from.dataStoredIn(DataLocation::Memory) || _from.baseType()->storageBytes() > 16, "");
return createFunction(functionName, [&]() {
bool dynamic = _to.isDynamicallyEncoded();
bool dynamicBase = _to.baseType()->isDynamicallyEncoded();
bool inMemory = _from.dataStoredIn(DataLocation::Memory);
Whiskers templ(
dynamicBase ?
R"(
function <functionName>(value, pos) <return> {
let length := <lengthFun>(value)
<storeLength> // might update pos
let headStart := pos
let tail := add(pos, mul(length, 0x20))
let srcPtr := <dataAreaFun>(value)
for { let i := 0 } lt(i, length) { i := add(i, 1) }
{
mstore(pos, sub(tail, headStart))
tail := <encodeToMemoryFun>(<arrayElementAccess>, tail)
srcPtr := <nextArrayElement>(srcPtr)
pos := add(pos, <elementEncodedSize>)
}
pos := tail
<assignEnd>
}
)" :
R"(
function <functionName>(value, pos) <return> {
let length := <lengthFun>(value)
<storeLength> // might update pos
let srcPtr := <dataAreaFun>(value)
for { let i := 0 } lt(i, length) { i := add(i, 1) }
{
<encodeToMemoryFun>(<arrayElementAccess>, pos)
srcPtr := <nextArrayElement>(srcPtr)
pos := add(pos, <elementEncodedSize>)
}
<assignEnd>
}
)"
);
templ("functionName", functionName);
templ("return", dynamic ? " -> end " : "");
templ("assignEnd", dynamic ? "end := pos" : "");
templ("lengthFun", arrayLengthFunction(_from));
if (_to.isDynamicallySized())
templ("storeLength", "mstore(pos, length) pos := add(pos, 0x20)");
else
templ("storeLength", "");
templ("dataAreaFun", arrayDataAreaFunction(_from));
templ("elementEncodedSize", toCompactHexWithPrefix(_to.baseType()->calldataEncodedSize()));
templ("encodeToMemoryFun", abiEncodingFunction(
*_from.baseType(),
*_to.baseType(),
_encodeAsLibraryTypes,
true
));
templ("arrayElementAccess", inMemory ? "mload(srcPtr)" : _from.baseType()->isValueType() ? "sload(srcPtr)" : "srcPtr" );
templ("nextArrayElement", nextArrayElementFunction(_from));
return templ.render();
});
}
string ABIFunctions::abiEncodingFunctionMemoryByteArray(
ArrayType const& _from,
ArrayType const& _to,
bool _encodeAsLibraryTypes
)
{
string functionName =
"abi_encode_" +
_from.identifier() +
"_to_" +
_to.identifier() +
(_encodeAsLibraryTypes ? "_library" : "");
solAssert(_from.isDynamicallySized() == _to.isDynamicallySized(), "");
solAssert(_from.length() == _to.length(), "");
solAssert(_from.dataStoredIn(DataLocation::Memory), "");
solAssert(_from.isByteArray(), "");
return createFunction(functionName, [&]() {
solAssert(_to.isByteArray(), "");
Whiskers templ(R"(
function <functionName>(value, pos) -> end {
let length := <lengthFun>(value)
mstore(pos, length)
<copyFun>(add(value, 0x20), add(pos, 0x20), length)
end := add(add(pos, 0x20), <roundUpFun>(length))
}
)");
templ("functionName", functionName);
templ("lengthFun", arrayLengthFunction(_from));
templ("copyFun", copyToMemoryFunction(false));
templ("roundUpFun", roundUpFunction());
return templ.render();
});
}
string ABIFunctions::abiEncodingFunctionCompactStorageArray(
ArrayType const& _from,
ArrayType const& _to,
bool _encodeAsLibraryTypes
)
{
string functionName =
"abi_encode_" +
_from.identifier() +
"_to_" +
_to.identifier() +
(_encodeAsLibraryTypes ? "_library" : "");
solAssert(_from.isDynamicallySized() == _to.isDynamicallySized(), "");
solAssert(_from.length() == _to.length(), "");
solAssert(_from.dataStoredIn(DataLocation::Storage), "");
return createFunction(functionName, [&]() {
if (_from.isByteArray())
{
solAssert(_to.isByteArray(), "");
Whiskers templ(R"(
function <functionName>(value, pos) -> ret {
let slotValue := sload(value)
switch and(slotValue, 1)
case 0 {
// short byte array
let length := and(div(slotValue, 2), 0x7f)
mstore(pos, length)
mstore(add(pos, 0x20), and(slotValue, not(0xff)))
ret := add(pos, 0x40)
}
case 1 {
// long byte array
let length := div(slotValue, 2)
mstore(pos, length)
pos := add(pos, 0x20)
let dataPos := <arrayDataSlot>(value)
let i := 0
for { } lt(i, length) { i := add(i, 0x20) } {
mstore(add(pos, i), sload(dataPos))
dataPos := add(dataPos, 1)
}
ret := add(pos, i)
}
}
)");
templ("functionName", functionName);
templ("arrayDataSlot", arrayDataAreaFunction(_from));
return templ.render();
}
else
{
// Multiple items per slot
solAssert(_from.baseType()->storageBytes() <= 16, "");
solAssert(!_from.baseType()->isDynamicallyEncoded(), "");
solAssert(_from.baseType()->isValueType(), "");
bool dynamic = _to.isDynamicallyEncoded();
size_t storageBytes = _from.baseType()->storageBytes();
size_t itemsPerSlot = 32 / storageBytes;
// This always writes full slot contents to memory, which might be
// more than desired, i.e. it writes beyond the end of memory.
Whiskers templ(
R"(
function <functionName>(value, pos) <return> {
let length := <lengthFun>(value)
<storeLength> // might update pos
let originalPos := pos
let srcPtr := <dataArea>(value)
for { let i := 0 } lt(i, length) { i := add(i, <itemsPerSlot>) }
{
let data := sload(srcPtr)
<#items>
<encodeToMemoryFun>(<shiftRightFun>(data), pos)
pos := add(pos, <elementEncodedSize>)
</items>
srcPtr := add(srcPtr, 1)
}
pos := add(originalPos, mul(length, <elementEncodedSize>))
<assignEnd>
}
)"
);
templ("functionName", functionName);
templ("return", dynamic ? " -> end " : "");
templ("assignEnd", dynamic ? "end := pos" : "");
templ("lengthFun", arrayLengthFunction(_from));
if (_to.isDynamicallySized())
templ("storeLength", "mstore(pos, length) pos := add(pos, 0x20)");
else
templ("storeLength", "");
templ("dataArea", arrayDataAreaFunction(_from));
templ("itemsPerSlot", to_string(itemsPerSlot));
string elementEncodedSize = toCompactHexWithPrefix(_to.baseType()->calldataEncodedSize());
templ("elementEncodedSize", elementEncodedSize);
string encodeToMemoryFun = abiEncodingFunction(
*_from.baseType(),
*_to.baseType(),
_encodeAsLibraryTypes,
true
);
templ("encodeToMemoryFun", encodeToMemoryFun);
std::vector<std::map<std::string, std::string>> items(itemsPerSlot);
for (size_t i = 0; i < itemsPerSlot; ++i)
items[i]["shiftRightFun"] = shiftRightFunction(i * storageBytes * 8, false);
templ("items", items);
return templ.render();
}
});
}
string ABIFunctions::abiEncodingFunctionStruct(
StructType const& _from,
StructType const& _to,
bool _encodeAsLibraryTypes
)
{
string functionName =
"abi_encode_" +
_from.identifier() +
"_to_" +
_to.identifier() +
(_encodeAsLibraryTypes ? "_library" : "");
solUnimplementedAssert(!_from.dataStoredIn(DataLocation::CallData), "");
solAssert(&_from.structDefinition() == &_to.structDefinition(), "");
return createFunction(functionName, [&]() {
bool fromStorage = _from.location() == DataLocation::Storage;
bool dynamic = _to.isDynamicallyEncoded();
Whiskers templ(R"(
function <functionName>(value, pos) <return> {
let tail := add(pos, <headSize>)
<init>
<#members>
{
// <memberName>
<encode>
}
</members>
<assignEnd>
}
)");
templ("functionName", functionName);
templ("return", dynamic ? " -> end " : "");
templ("assignEnd", dynamic ? "end := tail" : "");
// to avoid multiple loads from the same slot for subsequent members
templ("init", fromStorage ? "let slotValue := 0" : "");
u256 previousSlotOffset(-1);
u256 encodingOffset = 0;
vector<map<string, string>> members;
for (auto const& member: _to.members(nullptr))
{
solAssert(member.type, "");
if (!member.type->canLiveOutsideStorage())
continue;
solUnimplementedAssert(
member.type->mobileType() &&
member.type->mobileType()->interfaceType(_encodeAsLibraryTypes) &&
member.type->mobileType()->interfaceType(_encodeAsLibraryTypes)->encodingType(),
"Encoding type \"" + member.type->toString() + "\" not yet implemented."
);
auto memberTypeTo = member.type->mobileType()->interfaceType(_encodeAsLibraryTypes)->encodingType();
auto memberTypeFrom = _from.memberType(member.name);
solAssert(memberTypeFrom, "");
bool dynamicMember = memberTypeTo->isDynamicallyEncoded();
if (dynamicMember)
solAssert(dynamic, "");
Whiskers memberTempl(R"(
<preprocess>
let memberValue := <retrieveValue>
)" + (
dynamicMember ?
string(R"(
mstore(add(pos, <encodingOffset>), sub(tail, pos))
tail := <abiEncode>(memberValue, tail)
)") :
string(R"(
<abiEncode>(memberValue, add(pos, <encodingOffset>))
)")
)
);
if (fromStorage)
{
solAssert(memberTypeFrom->isValueType() == memberTypeTo->isValueType(), "");
u256 storageSlotOffset;
size_t intraSlotOffset;
tie(storageSlotOffset, intraSlotOffset) = _from.storageOffsetsOfMember(member.name);
if (memberTypeFrom->isValueType())
{
if (storageSlotOffset != previousSlotOffset)
{
memberTempl("preprocess", "slotValue := sload(add(value, " + toCompactHexWithPrefix(storageSlotOffset) + "))");
previousSlotOffset = storageSlotOffset;
}
else
memberTempl("preprocess", "");
memberTempl("retrieveValue", shiftRightFunction(intraSlotOffset * 8, false) + "(slotValue)");
}
else
{
solAssert(memberTypeFrom->dataStoredIn(DataLocation::Storage), "");
solAssert(intraSlotOffset == 0, "");
memberTempl("preprocess", "");
memberTempl("retrieveValue", "add(value, " + toCompactHexWithPrefix(storageSlotOffset) + ")");
}
}
else
{
memberTempl("preprocess", "");
string sourceOffset = toCompactHexWithPrefix(_from.memoryOffsetOfMember(member.name));
memberTempl("retrieveValue", "mload(add(value, " + sourceOffset + "))");
}
memberTempl("encodingOffset", toCompactHexWithPrefix(encodingOffset));
encodingOffset += dynamicMember ? 0x20 : memberTypeTo->calldataEncodedSize();
memberTempl("abiEncode", abiEncodingFunction(*memberTypeFrom, *memberTypeTo, _encodeAsLibraryTypes, false));
members.push_back({});
members.back()["encode"] = memberTempl.render();
members.back()["memberName"] = member.name;
}
templ("members", members);
templ("headSize", toCompactHexWithPrefix(encodingOffset));
return templ.render();
});
}
string ABIFunctions::abiEncodingFunctionStringLiteral(
Type const& _from,
Type const& _to,
bool _encodeAsLibraryTypes
)
{
solAssert(_from.category() == Type::Category::StringLiteral, "");
string functionName =
"abi_encode_" +
_from.identifier() +
"_to_" +
_to.identifier() +
(_encodeAsLibraryTypes ? "_library" : "");
return createFunction(functionName, [&]() {
auto const& strType = dynamic_cast<StringLiteralType const&>(_from);
string const& value = strType.value();
solAssert(_from.sizeOnStack() == 0, "");
if (_to.isDynamicallySized())
{
Whiskers templ(R"(
function <functionName>(pos) -> end {
mstore(pos, <length>)
<#word>
mstore(add(pos, <offset>), <wordValue>)
</word>
end := add(pos, <overallSize>)
}
)");
templ("functionName", functionName);
// TODO this can make use of CODECOPY for large strings once we have that in JULIA
size_t words = (value.size() + 31) / 32;
templ("overallSize", to_string(32 + words * 32));
templ("length", to_string(value.size()));
vector<map<string, string>> wordParams(words);
for (size_t i = 0; i < words; ++i)
{
wordParams[i]["offset"] = to_string(32 + i * 32);
wordParams[i]["wordValue"] = "0x" + h256(value.substr(32 * i, 32), h256::AlignLeft).hex();
}
templ("word", wordParams);
return templ.render();
}
else
{
solAssert(_to.category() == Type::Category::FixedBytes, "");
solAssert(value.size() <= 32, "");
Whiskers templ(R"(
function <functionName>(pos) {
mstore(pos, <wordValue>)
}
)");
templ("functionName", functionName);
templ("wordValue", "0x" + h256(value, h256::AlignLeft).hex());
return templ.render();
}
});
}
string ABIFunctions::abiEncodingFunctionFunctionType(
FunctionType const& _from,
Type const& _to,
bool _encodeAsLibraryTypes,
bool _compacted
)
{
solAssert(_from.kind() == FunctionType::Kind::External, "");
solAssert(_from == _to, "");
string functionName =
"abi_encode_" +
_from.identifier() +
"_to_" +
_to.identifier() +
(_compacted ? "_compacted" : "") +
(_encodeAsLibraryTypes ? "_library" : "");
if (_compacted)
{
return createFunction(functionName, [&]() {
return Whiskers(R"(
function <functionName>(addr_and_function_id, pos) {
mstore(pos, <cleanExtFun>(addr_and_function_id))
}
)")
("functionName", functionName)
("cleanExtFun", cleanupCombinedExternalFunctionIdFunction())
.render();
});
}
else
{
return createFunction(functionName, [&]() {
return Whiskers(R"(
function <functionName>(addr, function_id, pos) {
mstore(pos, <combineExtFun>(addr, function_id))
}
)")
("functionName", functionName)
("combineExtFun", combineExternalFunctionIdFunction())
.render();
});
}
}
string ABIFunctions::copyToMemoryFunction(bool _fromCalldata)
{
string functionName = "copy_" + string(_fromCalldata ? "calldata" : "memory") + "_to_memory";
return createFunction(functionName, [&]() {
if (_fromCalldata)
{
return Whiskers(R"(
function <functionName>(src, dst, length) {
calldatacopy(dst, src, length)
// clear end
mstore(add(dst, length), 0)
}
)")
("functionName", functionName)
.render();
}
else
{
return Whiskers(R"(
function <functionName>(src, dst, length) {
let i := 0
for { } lt(i, length) { i := add(i, 32) }
{
mstore(add(dst, i), mload(add(src, i)))
}
switch eq(i, length)
case 0 {
// clear end
mstore(add(dst, length), 0)
}
}
)")
("functionName", functionName)
.render();
}
});
}
string ABIFunctions::shiftLeftFunction(size_t _numBits)
{
string functionName = "shift_left_" + to_string(_numBits);
return createFunction(functionName, [&]() {
solAssert(_numBits < 256, "");
return
Whiskers(R"(function <functionName>(value) -> newValue {
newValue := mul(value, <multiplier>)
})")
("functionName", functionName)
("multiplier", toCompactHexWithPrefix(u256(1) << _numBits))
.render();
});
}
string ABIFunctions::shiftRightFunction(size_t _numBits, bool _signed)
{
string functionName = "shift_right_" + to_string(_numBits) + (_signed ? "_signed" : "_unsigned");
return createFunction(functionName, [&]() {
solAssert(_numBits < 256, "");
return
Whiskers(R"(function <functionName>(value) -> newValue {
newValue := <div>(value, <multiplier>)
})")
("functionName", functionName)
("div", _signed ? "sdiv" : "div")
("multiplier", toCompactHexWithPrefix(u256(1) << _numBits))
.render();
});
}
string ABIFunctions::roundUpFunction()
{
string functionName = "round_up_to_mul_of_32";
return createFunction(functionName, [&]() {
return
Whiskers(R"(function <functionName>(value) -> result {
result := and(add(value, 31), not(31))
})")
("functionName", functionName)
.render();
});
}
string ABIFunctions::arrayLengthFunction(ArrayType const& _type)
{
string functionName = "array_length_" + _type.identifier();
return createFunction(functionName, [&]() {
Whiskers w(R"(
function <functionName>(value) -> length {
<body>
}
)");
w("functionName", functionName);
string body;
if (!_type.isDynamicallySized())
body = "length := " + toCompactHexWithPrefix(_type.length());
else
{
switch (_type.location())
{
case DataLocation::CallData:
solAssert(false, "called regular array length function on calldata array");
break;
case DataLocation::Memory:
body = "length := mload(value)";
break;
case DataLocation::Storage:
if (_type.isByteArray())
{
// Retrieve length both for in-place strings and off-place strings:
// Computes (x & (0x100 * (ISZERO (x & 1)) - 1)) / 2
// i.e. for short strings (x & 1 == 0) it does (x & 0xff) / 2 and for long strings it
// computes (x & (-1)) / 2, which is equivalent to just x / 2.
body = R"(
length := sload(value)
let mask := sub(mul(0x100, iszero(and(length, 1))), 1)
length := div(and(length, mask), 2)
)";
}
else
body = "length := sload(value)";
break;
}
}
solAssert(!body.empty(), "");
w("body", body);
return w.render();
});
}
string ABIFunctions::arrayDataAreaFunction(ArrayType const& _type)
{
string functionName = "array_dataslot_" + _type.identifier();
return createFunction(functionName, [&]() {
if (_type.dataStoredIn(DataLocation::Memory))
{
if (_type.isDynamicallySized())
return Whiskers(R"(
function <functionName>(memPtr) -> dataPtr {
dataPtr := add(memPtr, 0x20)
}
)")
("functionName", functionName)
.render();
else
return Whiskers(R"(
function <functionName>(memPtr) -> dataPtr {
dataPtr := memPtr
}
)")
("functionName", functionName)
.render();
}
else if (_type.dataStoredIn(DataLocation::Storage))
{
if (_type.isDynamicallySized())
{
Whiskers w(R"(
function <functionName>(slot) -> dataSlot {
mstore(0, slot)
dataSlot := keccak256(0, 0x20)
}
)");
w("functionName", functionName);
return w.render();
}
else
{
Whiskers w(R"(
function <functionName>(slot) -> dataSlot {
dataSlot := slot
}
)");
w("functionName", functionName);
return w.render();
}
}
else
{
// Not used for calldata
solAssert(false, "");
}
});
}
string ABIFunctions::nextArrayElementFunction(ArrayType const& _type)
{
solAssert(!_type.isByteArray(), "");
solAssert(
_type.location() == DataLocation::Memory ||
_type.location() == DataLocation::Storage,
""
);
solAssert(
_type.location() == DataLocation::Memory ||
_type.baseType()->storageBytes() > 16,
""
);
string functionName = "array_nextElement_" + _type.identifier();
return createFunction(functionName, [&]() {
if (_type.location() == DataLocation::Memory)
return Whiskers(R"(
function <functionName>(memPtr) -> nextPtr {
nextPtr := add(memPtr, 0x20)
}
)")
("functionName", functionName)
.render();
else if (_type.location() == DataLocation::Storage)
return Whiskers(R"(
function <functionName>(slot) -> nextSlot {
nextSlot := add(slot, 1)
}
)")
("functionName", functionName)
.render();
else
solAssert(false, "");
});
}
string ABIFunctions::createFunction(string const& _name, function<string ()> const& _creator)
{
if (!m_requestedFunctions.count(_name))
{
auto fun = _creator();
solAssert(!fun.empty(), "");
m_requestedFunctions[_name] = fun;
}
return _name;
}
size_t ABIFunctions::headSize(TypePointers const& _targetTypes)
{
size_t headSize = 0;
for (auto const& t: _targetTypes)
{
if (t->isDynamicallyEncoded())
headSize += 0x20;
else
{
solAssert(t->calldataEncodedSize() > 0, "");
headSize += t->calldataEncodedSize();
}
}
return headSize;
}
