Method storageArrayIndexAccessFunction

libsolidity/codegen/YulUtilFunctions.cpp:2422–2465

}

std::string YulUtilFunctions::storageArrayIndexAccessFunction(ArrayType const& _type)
{
	std::string functionName = "storage_array_index_access_" + _type.identifier();
	return m_functionCollector.createFunction(functionName, [&]() {
		return Whiskers(R"(
			function <functionName>(array, index) -> slot, offset {
				let arrayLength := <arrayLen>(array)
				if iszero(lt(index, arrayLength)) { <panic>() }

				<?multipleItemsPerSlot>
					<?isBytesArray>
						switch lt(arrayLength, 0x20)
						case 0 {
							slot, offset := <indexAccessNoChecks>(array, index)
						}
						default {
							offset := sub(31, mod(index, 0x20))
							slot := array
						}
					<!isBytesArray>
						let dataArea := <dataAreaFunc>(array)
						slot := add(dataArea, div(index, <itemsPerSlot>))
						offset := mul(mod(index, <itemsPerSlot>), <storageBytes>)
					</isBytesArray>
				<!multipleItemsPerSlot>
					let dataArea := <dataAreaFunc>(array)
					slot := add(dataArea, mul(index, <storageSize>))
					offset := 0
				</multipleItemsPerSlot>
			}
		)")
		("functionName", functionName)
		("panic", panicFunction(PanicCode::ArrayOutOfBounds))
		("arrayLen", arrayLengthFunction(_type))
		("dataAreaFunc", arrayDataAreaFunction(_type))
		("indexAccessNoChecks", longByteArrayStorageIndexAccessNoCheckFunction())
		("multipleItemsPerSlot", _type.baseType()->storageBytes() <= 16)
		("isBytesArray", _type.isByteArrayOrString())
		("storageSize", _type.baseType()->storageSize().str())
		("storageBytes", toString(_type.baseType()->storageBytes()))
		("itemsPerSlot", std::to_string(32 / _type.baseType()->storageBytes()))
		.render();
	});
}

std::string YulUtilFunctions::memoryArrayIndexAccessFunction(ArrayType const& _type)
{