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Merge pull request #857 from LianaHus/StringToHash

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conversion for string to/from hash
This commit is contained in:
chriseth 2015-01-27 13:53:13 +01:00
commit 18fc2ed2d6
3 changed files with 69 additions and 25 deletions
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75
ExpressionCompiler.cpp
View File

@ -628,38 +628,65 @@ void ExpressionCompiler::appendTypeConversion(Type const& _typeOnStack, Type con
return;
Type::Category stackTypeCategory = _typeOnStack.getCategory();
Type::Category targetTypeCategory = _targetType.getCategory();
if (stackTypeCategory == Type::Category::INTEGER || stackTypeCategory == Type::Category::CONTRACT ||
stackTypeCategory == Type::Category::INTEGER_CONSTANT)
if (stackTypeCategory == Type::Category::STRING)
{
solAssert(targetTypeCategory == Type::Category::INTEGER || targetTypeCategory == Type::Category::CONTRACT, "");
IntegerType addressType(0, IntegerType::Modifier::ADDRESS);
IntegerType const& targetType = targetTypeCategory == Type::Category::INTEGER
? dynamic_cast<IntegerType const&>(_targetType) : addressType;
if (stackTypeCategory == Type::Category::INTEGER_CONSTANT)
if (targetTypeCategory == Type::Category::INTEGER)
{
IntegerConstantType const& constType = dynamic_cast<IntegerConstantType const&>(_typeOnStack);
// We know that the stack is clean, we only have to clean for a narrowing conversion
// where cleanup is forced.
if (targetType.getNumBits() < constType.getIntegerType()->getNumBits() && _cleanupNeeded)
appendHighBitsCleanup(targetType);
// conversion from string to hash. no need to clean the high bit
// only to shift right because of opposite alignment
IntegerType const& targetIntegerType = dynamic_cast<IntegerType const&>(_targetType);
StaticStringType const& typeOnStack = dynamic_cast<StaticStringType const&>(_typeOnStack);
solAssert(targetIntegerType.isHash(), "Only conversion between String and Hash is allowed.");
solAssert(targetIntegerType.getNumBits() == typeOnStack.getNumBytes() * 8, "The size should be the same.");
m_context << (u256(1) << (256 - typeOnStack.getNumBytes() * 8)) << eth::Instruction::SWAP1 << eth::Instruction::DIV;
}
else
{
IntegerType const& typeOnStack = stackTypeCategory == Type::Category::INTEGER
? dynamic_cast<IntegerType const&>(_typeOnStack) : addressType;
// Widening: clean up according to source type width
// Non-widening and force: clean up according to target type bits
if (targetType.getNumBits() > typeOnStack.getNumBits())
appendHighBitsCleanup(typeOnStack);
else if (_cleanupNeeded)
appendHighBitsCleanup(targetType);
solAssert(targetTypeCategory == Type::Category::STRING, "Invalid type conversion requested.");
// nothing to do, strings are high-order-bit-aligned
//@todo clear lower-order bytes if we allow explicit conversion to shorter strings
}
}
else if (stackTypeCategory == Type::Category::STRING)
else if (stackTypeCategory == Type::Category::INTEGER || stackTypeCategory == Type::Category::CONTRACT ||
stackTypeCategory == Type::Category::INTEGER_CONSTANT)
{
solAssert(targetTypeCategory == Type::Category::STRING, "");
// nothing to do, strings are high-order-bit-aligned
//@todo clear lower-order bytes if we allow explicit conversion to shorter strings
if (targetTypeCategory == Type::Category::STRING && stackTypeCategory == Type::Category::INTEGER)
{
// conversion from hash to string. no need to clean the high bit
// only to shift left because of opposite alignment
StaticStringType const& targetStringType = dynamic_cast<StaticStringType const&>(_targetType);
IntegerType const& typeOnStack = dynamic_cast<IntegerType const&>(_typeOnStack);
solAssert(typeOnStack.isHash(), "Only conversion between String and Hash is allowed.");
solAssert(typeOnStack.getNumBits() == targetStringType.getNumBytes() * 8, "The size should be the same.");
m_context << (u256(1) << (256 - typeOnStack.getNumBits())) << eth::Instruction::MUL;
}
else
{
solAssert(targetTypeCategory == Type::Category::INTEGER || targetTypeCategory == Type::Category::CONTRACT, "");
IntegerType addressType(0, IntegerType::Modifier::ADDRESS);
IntegerType const& targetType = targetTypeCategory == Type::Category::INTEGER
? dynamic_cast<IntegerType const&>(_targetType) : addressType;
if (stackTypeCategory == Type::Category::INTEGER_CONSTANT)
{
IntegerConstantType const& constType = dynamic_cast<IntegerConstantType const&>(_typeOnStack);
// We know that the stack is clean, we only have to clean for a narrowing conversion
// where cleanup is forced.
if (targetType.getNumBits() < constType.getIntegerType()->getNumBits() && _cleanupNeeded)
appendHighBitsCleanup(targetType);
}
else
{
IntegerType const& typeOnStack = stackTypeCategory == Type::Category::INTEGER
? dynamic_cast<IntegerType const&>(_typeOnStack) : addressType;
// Widening: clean up according to source type width
// Non-widening and force: clean up according to target type bits
if (targetType.getNumBits() > typeOnStack.getNumBits())
appendHighBitsCleanup(typeOnStack);
else if (_cleanupNeeded)
appendHighBitsCleanup(targetType);
}
}
}
else if (_typeOnStack != _targetType)
// All other types should not be convertible to non-equal types.

16
Types.cpp
View File

@ -140,6 +140,11 @@ bool IntegerType::isImplicitlyConvertibleTo(Type const& _convertTo) const
bool IntegerType::isExplicitlyConvertibleTo(Type const& _convertTo) const
{
if (_convertTo.getCategory() == Category::STRING)
{
StaticStringType const& convertTo = dynamic_cast<StaticStringType const&>(_convertTo);
return isHash() && (m_bits == convertTo.getNumBytes() * 8);
}
return _convertTo.getCategory() == getCategory() || _convertTo.getCategory() == Category::CONTRACT;
}
@ -367,6 +372,17 @@ bool StaticStringType::isImplicitlyConvertibleTo(Type const& _convertTo) const
return convertTo.m_bytes >= m_bytes;
}
bool StaticStringType::isExplicitlyConvertibleTo(Type const& _convertTo) const
{
if (_convertTo.getCategory() == Category::INTEGER)
{
IntegerType const& convertTo = dynamic_cast<IntegerType const&>(_convertTo);
if (convertTo.isHash() && (m_bytes * 8 == convertTo.getNumBits()))
return true;
}
return isImplicitlyConvertibleTo(_convertTo);
}
bool StaticStringType::operator==(Type const& _other) const
{
if (_other.getCategory() != getCategory())

3
Types.h
View File

@ -233,9 +233,10 @@ public:
/// if no type fits.
static std::shared_ptr<StaticStringType> smallestTypeForLiteral(std::string const& _literal);
StaticStringType(int _bytes);
explicit StaticStringType(int _bytes);
virtual bool isImplicitlyConvertibleTo(Type const& _convertTo) const override;
virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const override;
virtual bool operator==(Type const& _other) const override;
virtual unsigned getCalldataEncodedSize() const override { return m_bytes; }