Method incrementDynamicArraySize

libsolidity/codegen/ArrayUtils.cpp:449–491

}

void ArrayUtils::incrementDynamicArraySize(ArrayType const& _type) const
{
	solAssert(_type.location() == DataLocation::Storage, "");
	solAssert(_type.isDynamicallySized(), "");
	if (!_type.isByteArrayOrString() && _type.baseType()->storageBytes() < 32)
		solAssert(_type.baseType()->isValueType(), "Invalid storage size for non-value type.");

	if (_type.isByteArrayOrString())
	{
		// We almost always just add 2 (length of byte arrays is shifted left by one)
		// except for the case where we transition from a short byte array
		// to a long byte array, there we have to copy.
		// This happens if the length is exactly 31, which means that the
		// lowest-order byte (we actually use a mask with fewer bits) must
		// be (31*2+0) = 62

		m_context << Instruction::DUP1 << Instruction::SLOAD << Instruction::DUP1;
		m_context.callYulFunction(m_context.utilFunctions().extractByteArrayLengthFunction(), 1, 1);
		m_context.appendInlineAssembly(R"({
			// We have to copy if length is exactly 31, because that marks
			// the transition between in-place and out-of-place storage.
			switch length
			case 31
			{
				mstore(0, ref)
				let data_area := keccak256(0, 0x20)
				sstore(data_area, and(data, not(0xff)))
				// Set old length in new format (31 * 2 + 1)
				data := 63
			}
			sstore(ref, add(data, 2))
			// return new length in ref
			ref := add(length, 1)
		})", {"ref", "data", "length"});
		m_context << Instruction::POP << Instruction::POP;
	}
	else
		m_context.appendInlineAssembly(R"({
			let new_length := add(sload(ref), 1)
			sstore(ref, new_length)
			ref := new_length
		})", {"ref"});
}

void ArrayUtils::popStorageArrayElement(ArrayType const& _type) const
{