You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
582 lines
23 KiB
582 lines
23 KiB
/*
|
|
This file is part of cpp-ethereum.
|
|
|
|
cpp-ethereum 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.
|
|
|
|
cpp-ethereum 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 cpp-ethereum. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
/**
|
|
* @author Christian <c@ethdev.com>
|
|
* @date 2015
|
|
* Code generation utils that handle arrays.
|
|
*/
|
|
|
|
#include <libsolidity/ArrayUtils.h>
|
|
#include <libevmcore/Instruction.h>
|
|
#include <libsolidity/CompilerContext.h>
|
|
#include <libsolidity/CompilerUtils.h>
|
|
#include <libsolidity/Types.h>
|
|
#include <libsolidity/Utils.h>
|
|
#include <libsolidity/LValue.h>
|
|
|
|
using namespace std;
|
|
using namespace dev;
|
|
using namespace solidity;
|
|
|
|
void ArrayUtils::copyArrayToStorage(ArrayType const& _targetType, ArrayType const& _sourceType) const
|
|
{
|
|
// this copies source to target and also clears target if it was larger
|
|
// need to leave "target_ref target_byte_off" on the stack at the end
|
|
|
|
// stack layout: [source_ref] [source_byte_off] [source length] target_ref target_byte_off (top)
|
|
solAssert(_targetType.getLocation() == ArrayType::Location::Storage, "");
|
|
solAssert(
|
|
_sourceType.getLocation() == ArrayType::Location::CallData ||
|
|
_sourceType.getLocation() == ArrayType::Location::Storage,
|
|
"Given array location not implemented."
|
|
);
|
|
|
|
IntegerType uint256(256);
|
|
Type const* targetBaseType = _targetType.isByteArray() ? &uint256 : &(*_targetType.getBaseType());
|
|
Type const* sourceBaseType = _sourceType.isByteArray() ? &uint256 : &(*_sourceType.getBaseType());
|
|
|
|
// TODO unroll loop for small sizes
|
|
|
|
bool sourceIsStorage = _sourceType.getLocation() == ArrayType::Location::Storage;
|
|
bool directCopy = sourceIsStorage && sourceBaseType->isValueType() && *sourceBaseType == *targetBaseType;
|
|
bool haveByteOffsetSource = !directCopy && sourceIsStorage && sourceBaseType->getStorageBytes() <= 16;
|
|
bool haveByteOffsetTarget = !directCopy && targetBaseType->getStorageBytes() <= 16;
|
|
unsigned byteOffsetSize = (haveByteOffsetSource ? 1 : 0) + (haveByteOffsetTarget ? 1 : 0);
|
|
|
|
// stack: source_ref [source_byte_off] [source_length] target_ref target_byte_off
|
|
// store target_ref
|
|
// arrays always start at zero byte offset, pop offset
|
|
m_context << eth::Instruction::POP;
|
|
for (unsigned i = _sourceType.getSizeOnStack(); i > 0; --i)
|
|
m_context << eth::swapInstruction(i);
|
|
// stack: target_ref source_ref [source_byte_off] [source_length]
|
|
if (sourceIsStorage)
|
|
// arrays always start at zero byte offset, pop offset
|
|
m_context << eth::Instruction::POP;
|
|
// stack: target_ref source_ref [source_length]
|
|
// retrieve source length
|
|
if (_sourceType.getLocation() != ArrayType::Location::CallData || !_sourceType.isDynamicallySized())
|
|
retrieveLength(_sourceType); // otherwise, length is already there
|
|
// stack: target_ref source_ref source_length
|
|
m_context << eth::Instruction::DUP3;
|
|
// stack: target_ref source_ref source_length target_ref
|
|
retrieveLength(_targetType);
|
|
// stack: target_ref source_ref source_length target_ref target_length
|
|
if (_targetType.isDynamicallySized())
|
|
// store new target length
|
|
m_context << eth::Instruction::DUP3 << eth::Instruction::DUP3 << eth::Instruction::SSTORE;
|
|
if (sourceBaseType->getCategory() == Type::Category::Mapping)
|
|
{
|
|
solAssert(targetBaseType->getCategory() == Type::Category::Mapping, "");
|
|
solAssert(_sourceType.getLocation() == ArrayType::Location::Storage, "");
|
|
// nothing to copy
|
|
m_context
|
|
<< eth::Instruction::POP << eth::Instruction::POP
|
|
<< eth::Instruction::POP << eth::Instruction::POP;
|
|
m_context << u256(0);
|
|
return;
|
|
}
|
|
// compute hashes (data positions)
|
|
m_context << eth::Instruction::SWAP1;
|
|
if (_targetType.isDynamicallySized())
|
|
CompilerUtils(m_context).computeHashStatic();
|
|
// stack: target_ref source_ref source_length target_length target_data_pos
|
|
m_context << eth::Instruction::SWAP1;
|
|
convertLengthToSize(_targetType);
|
|
m_context << eth::Instruction::DUP2 << eth::Instruction::ADD;
|
|
// stack: target_ref source_ref source_length target_data_pos target_data_end
|
|
m_context << eth::Instruction::SWAP3;
|
|
// stack: target_ref target_data_end source_length target_data_pos source_ref
|
|
// skip copying if source length is zero
|
|
m_context << eth::Instruction::DUP3 << eth::Instruction::ISZERO;
|
|
eth::AssemblyItem copyLoopEndWithoutByteOffset = m_context.newTag();
|
|
m_context.appendConditionalJumpTo(copyLoopEndWithoutByteOffset);
|
|
|
|
if (_sourceType.getLocation() == ArrayType::Location::Storage && _sourceType.isDynamicallySized())
|
|
CompilerUtils(m_context).computeHashStatic();
|
|
// stack: target_ref target_data_end source_length target_data_pos source_data_pos
|
|
m_context << eth::Instruction::SWAP2;
|
|
convertLengthToSize(_sourceType);
|
|
m_context << eth::Instruction::DUP3 << eth::Instruction::ADD;
|
|
// stack: target_ref target_data_end source_data_pos target_data_pos source_data_end
|
|
if (haveByteOffsetTarget)
|
|
m_context << u256(0);
|
|
if (haveByteOffsetSource)
|
|
m_context << u256(0);
|
|
// stack: target_ref target_data_end source_data_pos target_data_pos source_data_end [target_byte_offset] [source_byte_offset]
|
|
eth::AssemblyItem copyLoopStart = m_context.newTag();
|
|
m_context << copyLoopStart;
|
|
// check for loop condition
|
|
m_context
|
|
<< eth::dupInstruction(3 + byteOffsetSize) << eth::dupInstruction(2 + byteOffsetSize)
|
|
<< eth::Instruction::GT << eth::Instruction::ISZERO;
|
|
eth::AssemblyItem copyLoopEnd = m_context.newTag();
|
|
m_context.appendConditionalJumpTo(copyLoopEnd);
|
|
// stack: target_ref target_data_end source_data_pos target_data_pos source_data_end [target_byte_offset] [source_byte_offset]
|
|
// copy
|
|
if (sourceBaseType->getCategory() == Type::Category::Array)
|
|
{
|
|
solAssert(byteOffsetSize == 0, "Byte offset for array as base type.");
|
|
m_context << eth::Instruction::DUP3;
|
|
if (sourceIsStorage)
|
|
m_context << u256(0);
|
|
m_context << eth::dupInstruction(sourceIsStorage ? 4 : 3) << u256(0);
|
|
copyArrayToStorage(
|
|
dynamic_cast<ArrayType const&>(*targetBaseType),
|
|
dynamic_cast<ArrayType const&>(*sourceBaseType)
|
|
);
|
|
m_context << eth::Instruction::POP << eth::Instruction::POP;
|
|
}
|
|
else if (directCopy)
|
|
{
|
|
solAssert(byteOffsetSize == 0, "Byte offset for direct copy.");
|
|
m_context
|
|
<< eth::Instruction::DUP3 << eth::Instruction::SLOAD
|
|
<< eth::Instruction::DUP3 << eth::Instruction::SSTORE;
|
|
}
|
|
else
|
|
{
|
|
// Note that we have to copy each element on its own in case conversion is involved.
|
|
// We might copy too much if there is padding at the last element, but this way end
|
|
// checking is easier.
|
|
// stack: target_ref target_data_end source_data_pos target_data_pos source_data_end [target_byte_offset] [source_byte_offset]
|
|
m_context << eth::dupInstruction(3 + byteOffsetSize);
|
|
if (_sourceType.getLocation() == ArrayType::Location::Storage)
|
|
{
|
|
if (haveByteOffsetSource)
|
|
m_context << eth::Instruction::DUP2;
|
|
else
|
|
m_context << u256(0);
|
|
StorageItem(m_context, *sourceBaseType).retrieveValue(SourceLocation(), true);
|
|
}
|
|
else if (sourceBaseType->isValueType())
|
|
CompilerUtils(m_context).loadFromMemoryDynamic(*sourceBaseType, true, true, false);
|
|
else
|
|
solAssert(false, "Copying of unknown type requested: " + sourceBaseType->toString());
|
|
// stack: target_ref target_data_end source_data_pos target_data_pos source_data_end [target_byte_offset] [source_byte_offset] <source_value>...
|
|
solAssert(2 + byteOffsetSize + sourceBaseType->getSizeOnStack() <= 16, "Stack too deep.");
|
|
// fetch target storage reference
|
|
m_context << eth::dupInstruction(2 + byteOffsetSize + sourceBaseType->getSizeOnStack());
|
|
if (haveByteOffsetTarget)
|
|
m_context << eth::dupInstruction(1 + byteOffsetSize + sourceBaseType->getSizeOnStack());
|
|
else
|
|
m_context << u256(0);
|
|
StorageItem(m_context, *targetBaseType).storeValue(*sourceBaseType, SourceLocation(), true);
|
|
}
|
|
// stack: target_ref target_data_end source_data_pos target_data_pos source_data_end [target_byte_offset] [source_byte_offset]
|
|
// increment source
|
|
if (haveByteOffsetSource)
|
|
incrementByteOffset(sourceBaseType->getStorageBytes(), 1, haveByteOffsetTarget ? 5 : 4);
|
|
else
|
|
m_context
|
|
<< eth::swapInstruction(2 + byteOffsetSize)
|
|
<< (sourceIsStorage ? sourceBaseType->getStorageSize() : sourceBaseType->getCalldataEncodedSize())
|
|
<< eth::Instruction::ADD
|
|
<< eth::swapInstruction(2 + byteOffsetSize);
|
|
// increment target
|
|
if (haveByteOffsetTarget)
|
|
incrementByteOffset(targetBaseType->getStorageBytes(), byteOffsetSize, byteOffsetSize + 2);
|
|
else
|
|
m_context
|
|
<< eth::swapInstruction(1 + byteOffsetSize)
|
|
<< targetBaseType->getStorageSize()
|
|
<< eth::Instruction::ADD
|
|
<< eth::swapInstruction(1 + byteOffsetSize);
|
|
m_context.appendJumpTo(copyLoopStart);
|
|
m_context << copyLoopEnd;
|
|
if (haveByteOffsetTarget)
|
|
{
|
|
// clear elements that might be left over in the current slot in target
|
|
// stack: target_ref target_data_end source_data_pos target_data_pos source_data_end target_byte_offset [source_byte_offset]
|
|
m_context << eth::dupInstruction(byteOffsetSize) << eth::Instruction::ISZERO;
|
|
eth::AssemblyItem copyCleanupLoopEnd = m_context.appendConditionalJump();
|
|
m_context << eth::dupInstruction(2 + byteOffsetSize) << eth::dupInstruction(1 + byteOffsetSize);
|
|
StorageItem(m_context, *targetBaseType).setToZero(SourceLocation(), true);
|
|
incrementByteOffset(targetBaseType->getStorageBytes(), byteOffsetSize, byteOffsetSize + 2);
|
|
m_context.appendJumpTo(copyLoopEnd);
|
|
|
|
m_context << copyCleanupLoopEnd;
|
|
m_context << eth::Instruction::POP; // might pop the source, but then target is popped next
|
|
}
|
|
if (haveByteOffsetSource)
|
|
m_context << eth::Instruction::POP;
|
|
m_context << copyLoopEndWithoutByteOffset;
|
|
|
|
// zero-out leftovers in target
|
|
// stack: target_ref target_data_end source_data_pos target_data_pos_updated source_data_end
|
|
m_context << eth::Instruction::POP << eth::Instruction::SWAP1 << eth::Instruction::POP;
|
|
// stack: target_ref target_data_end target_data_pos_updated
|
|
clearStorageLoop(*targetBaseType);
|
|
m_context << eth::Instruction::POP;
|
|
m_context << u256(0);
|
|
}
|
|
|
|
void ArrayUtils::clearArray(ArrayType const& _type) const
|
|
{
|
|
unsigned stackHeightStart = m_context.getStackHeight();
|
|
solAssert(_type.getLocation() == ArrayType::Location::Storage, "");
|
|
if (_type.getBaseType()->getStorageBytes() < 32)
|
|
{
|
|
solAssert(_type.getBaseType()->isValueType(), "Invalid storage size for non-value type.");
|
|
solAssert(_type.getBaseType()->getStorageSize() <= 1, "Invalid storage size for type.");
|
|
}
|
|
if (_type.getBaseType()->isValueType())
|
|
solAssert(_type.getBaseType()->getStorageSize() <= 1, "Invalid size for value type.");
|
|
|
|
m_context << eth::Instruction::POP; // remove byte offset
|
|
if (_type.isDynamicallySized())
|
|
clearDynamicArray(_type);
|
|
else if (_type.getLength() == 0 || _type.getBaseType()->getCategory() == Type::Category::Mapping)
|
|
m_context << eth::Instruction::POP;
|
|
else if (_type.getBaseType()->isValueType() && _type.getStorageSize() <= 5)
|
|
{
|
|
// unroll loop for small arrays @todo choose a good value
|
|
// Note that we loop over storage slots here, not elements.
|
|
for (unsigned i = 1; i < _type.getStorageSize(); ++i)
|
|
m_context
|
|
<< u256(0) << eth::Instruction::DUP2 << eth::Instruction::SSTORE
|
|
<< u256(1) << eth::Instruction::ADD;
|
|
m_context << u256(0) << eth::Instruction::SWAP1 << eth::Instruction::SSTORE;
|
|
}
|
|
else if (!_type.getBaseType()->isValueType() && _type.getLength() <= 4)
|
|
{
|
|
// unroll loop for small arrays @todo choose a good value
|
|
solAssert(_type.getBaseType()->getStorageBytes() >= 32, "Invalid storage size.");
|
|
for (unsigned i = 1; i < _type.getLength(); ++i)
|
|
{
|
|
m_context << u256(0);
|
|
StorageItem(m_context, *_type.getBaseType()).setToZero(SourceLocation(), false);
|
|
m_context
|
|
<< eth::Instruction::POP
|
|
<< u256(_type.getBaseType()->getStorageSize()) << eth::Instruction::ADD;
|
|
}
|
|
m_context << u256(0);
|
|
StorageItem(m_context, *_type.getBaseType()).setToZero(SourceLocation(), true);
|
|
}
|
|
else
|
|
{
|
|
m_context << eth::Instruction::DUP1 << _type.getLength();
|
|
convertLengthToSize(_type);
|
|
m_context << eth::Instruction::ADD << eth::Instruction::SWAP1;
|
|
if (_type.getBaseType()->getStorageBytes() < 32)
|
|
clearStorageLoop(IntegerType(256));
|
|
else
|
|
clearStorageLoop(*_type.getBaseType());
|
|
m_context << eth::Instruction::POP;
|
|
}
|
|
solAssert(m_context.getStackHeight() == stackHeightStart - 2, "");
|
|
}
|
|
|
|
void ArrayUtils::clearDynamicArray(ArrayType const& _type) const
|
|
{
|
|
solAssert(_type.getLocation() == ArrayType::Location::Storage, "");
|
|
solAssert(_type.isDynamicallySized(), "");
|
|
|
|
unsigned stackHeightStart = m_context.getStackHeight();
|
|
// fetch length
|
|
m_context << eth::Instruction::DUP1 << eth::Instruction::SLOAD;
|
|
// set length to zero
|
|
m_context << u256(0) << eth::Instruction::DUP3 << eth::Instruction::SSTORE;
|
|
// stack: ref old_length
|
|
convertLengthToSize(_type);
|
|
// compute data positions
|
|
m_context << eth::Instruction::SWAP1;
|
|
CompilerUtils(m_context).computeHashStatic();
|
|
// stack: len data_pos
|
|
m_context << eth::Instruction::SWAP1 << eth::Instruction::DUP2 << eth::Instruction::ADD
|
|
<< eth::Instruction::SWAP1;
|
|
// stack: data_pos_end data_pos
|
|
if (_type.isByteArray() || _type.getBaseType()->getStorageBytes() < 32)
|
|
clearStorageLoop(IntegerType(256));
|
|
else
|
|
clearStorageLoop(*_type.getBaseType());
|
|
// cleanup
|
|
m_context << eth::Instruction::POP;
|
|
solAssert(m_context.getStackHeight() == stackHeightStart - 1, "");
|
|
}
|
|
|
|
void ArrayUtils::resizeDynamicArray(const ArrayType& _type) const
|
|
{
|
|
solAssert(_type.getLocation() == ArrayType::Location::Storage, "");
|
|
solAssert(_type.isDynamicallySized(), "");
|
|
if (!_type.isByteArray() && _type.getBaseType()->getStorageBytes() < 32)
|
|
solAssert(_type.getBaseType()->isValueType(), "Invalid storage size for non-value type.");
|
|
|
|
unsigned stackHeightStart = m_context.getStackHeight();
|
|
eth::AssemblyItem resizeEnd = m_context.newTag();
|
|
|
|
// stack: ref new_length
|
|
// fetch old length
|
|
m_context << eth::Instruction::DUP2 << eth::Instruction::SLOAD;
|
|
// stack: ref new_length old_length
|
|
// store new length
|
|
m_context << eth::Instruction::DUP2 << eth::Instruction::DUP4 << eth::Instruction::SSTORE;
|
|
// skip if size is not reduced
|
|
m_context << eth::Instruction::DUP2 << eth::Instruction::DUP2
|
|
<< eth::Instruction::ISZERO << eth::Instruction::GT;
|
|
m_context.appendConditionalJumpTo(resizeEnd);
|
|
|
|
// size reduced, clear the end of the array
|
|
// stack: ref new_length old_length
|
|
convertLengthToSize(_type);
|
|
m_context << eth::Instruction::DUP2;
|
|
convertLengthToSize(_type);
|
|
// stack: ref new_length old_size new_size
|
|
// compute data positions
|
|
m_context << eth::Instruction::DUP4;
|
|
CompilerUtils(m_context).computeHashStatic();
|
|
// stack: ref new_length old_size new_size data_pos
|
|
m_context << eth::Instruction::SWAP2 << eth::Instruction::DUP3 << eth::Instruction::ADD;
|
|
// stack: ref new_length data_pos new_size delete_end
|
|
m_context << eth::Instruction::SWAP2 << eth::Instruction::ADD;
|
|
// stack: ref new_length delete_end delete_start
|
|
if (_type.isByteArray() || _type.getBaseType()->getStorageBytes() < 32)
|
|
clearStorageLoop(IntegerType(256));
|
|
else
|
|
clearStorageLoop(*_type.getBaseType());
|
|
|
|
m_context << resizeEnd;
|
|
// cleanup
|
|
m_context << eth::Instruction::POP << eth::Instruction::POP << eth::Instruction::POP;
|
|
solAssert(m_context.getStackHeight() == stackHeightStart - 2, "");
|
|
}
|
|
|
|
void ArrayUtils::clearStorageLoop(Type const& _type) const
|
|
{
|
|
unsigned stackHeightStart = m_context.getStackHeight();
|
|
if (_type.getCategory() == Type::Category::Mapping)
|
|
{
|
|
m_context << eth::Instruction::POP;
|
|
return;
|
|
}
|
|
// stack: end_pos pos
|
|
eth::AssemblyItem loopStart = m_context.newTag();
|
|
m_context << loopStart;
|
|
// check for loop condition
|
|
m_context << eth::Instruction::DUP1 << eth::Instruction::DUP3
|
|
<< eth::Instruction::GT << eth::Instruction::ISZERO;
|
|
eth::AssemblyItem zeroLoopEnd = m_context.newTag();
|
|
m_context.appendConditionalJumpTo(zeroLoopEnd);
|
|
// delete
|
|
m_context << u256(0);
|
|
StorageItem(m_context, _type).setToZero(SourceLocation(), false);
|
|
m_context << eth::Instruction::POP;
|
|
// increment
|
|
m_context << u256(1) << eth::Instruction::ADD;
|
|
m_context.appendJumpTo(loopStart);
|
|
// cleanup
|
|
m_context << zeroLoopEnd;
|
|
m_context << eth::Instruction::POP;
|
|
solAssert(m_context.getStackHeight() == stackHeightStart - 1, "");
|
|
}
|
|
|
|
void ArrayUtils::convertLengthToSize(ArrayType const& _arrayType, bool _pad) const
|
|
{
|
|
if (_arrayType.getLocation() == ArrayType::Location::Storage)
|
|
{
|
|
if (_arrayType.isByteArray())
|
|
m_context << u256(31) << eth::Instruction::ADD
|
|
<< u256(32) << eth::Instruction::SWAP1 << eth::Instruction::DIV;
|
|
else if (_arrayType.getBaseType()->getStorageSize() <= 1)
|
|
{
|
|
unsigned baseBytes = _arrayType.getBaseType()->getStorageBytes();
|
|
if (baseBytes == 0)
|
|
m_context << eth::Instruction::POP << u256(1);
|
|
else if (baseBytes <= 16)
|
|
{
|
|
unsigned itemsPerSlot = 32 / baseBytes;
|
|
m_context
|
|
<< u256(itemsPerSlot - 1) << eth::Instruction::ADD
|
|
<< u256(itemsPerSlot) << eth::Instruction::SWAP1 << eth::Instruction::DIV;
|
|
}
|
|
}
|
|
else
|
|
m_context << _arrayType.getBaseType()->getStorageSize() << eth::Instruction::MUL;
|
|
}
|
|
else
|
|
{
|
|
if (!_arrayType.isByteArray())
|
|
m_context << _arrayType.getBaseType()->getCalldataEncodedSize() << eth::Instruction::MUL;
|
|
else if (_pad)
|
|
m_context << u256(31) << eth::Instruction::ADD
|
|
<< u256(32) << eth::Instruction::DUP1
|
|
<< eth::Instruction::SWAP2 << eth::Instruction::DIV << eth::Instruction::MUL;
|
|
}
|
|
}
|
|
|
|
void ArrayUtils::retrieveLength(ArrayType const& _arrayType) const
|
|
{
|
|
if (!_arrayType.isDynamicallySized())
|
|
m_context << _arrayType.getLength();
|
|
else
|
|
{
|
|
m_context << eth::Instruction::DUP1;
|
|
switch (_arrayType.getLocation())
|
|
{
|
|
case ArrayType::Location::CallData:
|
|
// length is stored on the stack
|
|
break;
|
|
case ArrayType::Location::Memory:
|
|
m_context << eth::Instruction::MLOAD;
|
|
break;
|
|
case ArrayType::Location::Storage:
|
|
m_context << eth::Instruction::SLOAD;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
void ArrayUtils::accessIndex(ArrayType const& _arrayType) const
|
|
{
|
|
ArrayType::Location location = _arrayType.getLocation();
|
|
eth::Instruction load =
|
|
location == ArrayType::Location::Storage ? eth::Instruction::SLOAD :
|
|
location == ArrayType::Location::Memory ? eth::Instruction::MLOAD :
|
|
eth::Instruction::CALLDATALOAD;
|
|
|
|
// retrieve length
|
|
if (!_arrayType.isDynamicallySized())
|
|
m_context << _arrayType.getLength();
|
|
else if (location == ArrayType::Location::CallData)
|
|
// length is stored on the stack
|
|
m_context << eth::Instruction::SWAP1;
|
|
else
|
|
m_context << eth::Instruction::DUP2 << load;
|
|
// stack: <base_ref> <index> <length>
|
|
// check out-of-bounds access
|
|
m_context << eth::Instruction::DUP2 << eth::Instruction::LT;
|
|
eth::AssemblyItem legalAccess = m_context.appendConditionalJump();
|
|
// out-of-bounds access throws exception (just STOP for now)
|
|
m_context << eth::Instruction::STOP;
|
|
|
|
m_context << legalAccess;
|
|
// stack: <base_ref> <index>
|
|
if (_arrayType.isByteArray())
|
|
switch (location)
|
|
{
|
|
case ArrayType::Location::Storage:
|
|
// byte array index storage lvalue on stack (goal):
|
|
// <ref> <byte_number> = <base_ref + index / 32> <index % 32>
|
|
m_context << u256(32) << eth::Instruction::SWAP2;
|
|
CompilerUtils(m_context).computeHashStatic();
|
|
// stack: 32 index data_ref
|
|
m_context
|
|
<< eth::Instruction::DUP3 << eth::Instruction::DUP3
|
|
<< eth::Instruction::DIV << eth::Instruction::ADD
|
|
// stack: 32 index (data_ref + index / 32)
|
|
<< eth::Instruction::SWAP2 << eth::Instruction::SWAP1
|
|
<< eth::Instruction::MOD;
|
|
break;
|
|
case ArrayType::Location::CallData:
|
|
// no lvalue, just retrieve the value
|
|
m_context
|
|
<< eth::Instruction::ADD << eth::Instruction::CALLDATALOAD
|
|
<< ((u256(0xff) << (256 - 8))) << eth::Instruction::AND;
|
|
break;
|
|
case ArrayType::Location::Memory:
|
|
solAssert(false, "Memory lvalues not yet implemented.");
|
|
}
|
|
else
|
|
{
|
|
// stack: <base_ref> <index>
|
|
m_context << eth::Instruction::SWAP1;
|
|
if (_arrayType.isDynamicallySized())
|
|
{
|
|
if (location == ArrayType::Location::Storage)
|
|
CompilerUtils(m_context).computeHashStatic();
|
|
else if (location == ArrayType::Location::Memory)
|
|
m_context << u256(32) << eth::Instruction::ADD;
|
|
}
|
|
// stack: <index> <data_ref>
|
|
switch (location)
|
|
{
|
|
case ArrayType::Location::CallData:
|
|
m_context
|
|
<< eth::Instruction::SWAP1 << _arrayType.getBaseType()->getCalldataEncodedSize()
|
|
<< eth::Instruction::MUL << eth::Instruction::ADD;
|
|
if (_arrayType.getBaseType()->isValueType())
|
|
CompilerUtils(m_context).loadFromMemoryDynamic(*_arrayType.getBaseType(), true, true, false);
|
|
break;
|
|
case ArrayType::Location::Storage:
|
|
m_context << eth::Instruction::SWAP1;
|
|
if (_arrayType.getBaseType()->getStorageBytes() <= 16)
|
|
{
|
|
// stack: <data_ref> <index>
|
|
// goal:
|
|
// <ref> <byte_number> = <base_ref + index / itemsPerSlot> <(index % itemsPerSlot) * byteSize>
|
|
unsigned byteSize = _arrayType.getBaseType()->getStorageBytes();
|
|
solAssert(byteSize != 0, "");
|
|
unsigned itemsPerSlot = 32 / byteSize;
|
|
m_context << u256(itemsPerSlot) << eth::Instruction::SWAP2;
|
|
// stack: itemsPerSlot index data_ref
|
|
m_context
|
|
<< eth::Instruction::DUP3 << eth::Instruction::DUP3
|
|
<< eth::Instruction::DIV << eth::Instruction::ADD
|
|
// stack: itemsPerSlot index (data_ref + index / itemsPerSlot)
|
|
<< eth::Instruction::SWAP2 << eth::Instruction::SWAP1
|
|
<< eth::Instruction::MOD
|
|
<< u256(byteSize) << eth::Instruction::MUL;
|
|
}
|
|
else
|
|
{
|
|
if (_arrayType.getBaseType()->getStorageSize() != 1)
|
|
m_context << _arrayType.getBaseType()->getStorageSize() << eth::Instruction::MUL;
|
|
m_context << eth::Instruction::ADD << u256(0);
|
|
}
|
|
break;
|
|
case ArrayType::Location::Memory:
|
|
solAssert(false, "Memory lvalues not yet implemented.");
|
|
}
|
|
}
|
|
}
|
|
|
|
void ArrayUtils::incrementByteOffset(unsigned _byteSize, unsigned _byteOffsetPosition, unsigned _storageOffsetPosition) const
|
|
{
|
|
solAssert(_byteSize < 32, "");
|
|
solAssert(_byteSize != 0, "");
|
|
// We do the following, but avoiding jumps:
|
|
// byteOffset += byteSize
|
|
// if (byteOffset + byteSize > 32)
|
|
// {
|
|
// storageOffset++;
|
|
// byteOffset = 0;
|
|
// }
|
|
if (_byteOffsetPosition > 1)
|
|
m_context << eth::swapInstruction(_byteOffsetPosition - 1);
|
|
m_context << u256(_byteSize) << eth::Instruction::ADD;
|
|
if (_byteOffsetPosition > 1)
|
|
m_context << eth::swapInstruction(_byteOffsetPosition - 1);
|
|
// compute, X := (byteOffset + byteSize - 1) / 32, should be 1 iff byteOffset + bytesize > 32
|
|
m_context
|
|
<< u256(32) << eth::dupInstruction(1 + _byteOffsetPosition) << u256(_byteSize - 1)
|
|
<< eth::Instruction::ADD << eth::Instruction::DIV;
|
|
// increment storage offset if X == 1 (just add X to it)
|
|
// stack: X
|
|
m_context
|
|
<< eth::swapInstruction(_storageOffsetPosition) << eth::dupInstruction(_storageOffsetPosition + 1)
|
|
<< eth::Instruction::ADD << eth::swapInstruction(_storageOffsetPosition);
|
|
// stack: X
|
|
// set source_byte_offset to zero if X == 1 (using source_byte_offset *= 1 - X)
|
|
m_context << u256(1) << eth::Instruction::SUB;
|
|
// stack: 1 - X
|
|
if (_byteOffsetPosition == 1)
|
|
m_context << eth::Instruction::MUL;
|
|
else
|
|
m_context
|
|
<< eth::dupInstruction(_byteOffsetPosition + 1) << eth::Instruction::MUL
|
|
<< eth::swapInstruction(_byteOffsetPosition) << eth::Instruction::POP;
|
|
}
|
|
|