/// <summary>
/// Provides the cost of gas for a given size of memory in words.
/// </summary>
/// <param name="wordCount">The target amount of words of memory.</param>
/// <returns>Returns the cost of gas for the given size of memory.</returns>
public static BigInteger GetMemoryAllocationCost(EthereumRelease currentVersion, BigInteger wordCount)
{
// Calculate the cost of gas for the given amount of words of memory.
BigInteger cost = (wordCount * GAS_MEMORY_BASE) + (BigInteger.Pow(wordCount, 2) / 512);
return(cost);
}
/// <summary>
/// Obtains the base gas cost of executing the given opcode on the given Ethereum release version.
/// </summary>
/// <param name="currentVersion">The release of Ethereum to assume when obtaining the base gas cost for the given opcode.</param>
/// <param name="opcode">The opcode to obtain the base gas cost for.</param>
/// <returns>Returns the base gas cost for the given instruction on the given Ethereum release.</returns>
public static uint?GetInstructionBaseGasCost(EthereumRelease currentVersion, InstructionOpcode opcode)
{
// Obtain the cost for this version. It is null if it does not exist yet, or was never declared.
uint cost = 0;
if (_baseGasLookup[currentVersion].TryGetValue(opcode, out cost))
{
return(cost);
}
else
{
return(null);
}
}
/// <summary>
/// Sets the Ethereum release to be used in the configuration.
/// </summary>
/// <param name="releaseVersion">The release version to set this configuration to.</param>
public void SetEthereumReleaseBlockStarts(EthereumRelease releaseVersion)
{
// Obtain all release options.
EthereumRelease[] options = (EthereumRelease[])Enum.GetValues(typeof(EthereumRelease));
// Loop through every option, if we are at this version or below, set the block number to 0 so we'll always be considered in this version, set all other block numbers to max so we never reach it.
foreach (EthereumRelease option in options)
{
if (option <= releaseVersion)
{
EthereumReleaseBlockStart[option] = 0;
}
else
{
EthereumReleaseBlockStart[option] = EVMDefinitions.UINT256_MAX_VALUE;
}
}
// TODO: Temporary cheap fix. Replace this.
EthereumReleaseBlockStart[EthereumRelease.DAO] = EVMDefinitions.UINT256_MAX_VALUE;
}
/// <summary>
/// Given a state, updates the current configuration's Ethereum release to accomodate for the current block number.
/// </summary>
/// <param name="state">The state which we wish to based our versioning off of.</param>
public void UpdateEthereumRelease(State state)
{
// Declare our release type
EthereumRelease releaseType = EthereumRelease.Frontier;
// Obtain all release options.
EthereumRelease[] options = (EthereumRelease[])Enum.GetValues(typeof(EthereumRelease));
// Loop through every option, if we passed the declared block number, and this version is higher, set the version.
foreach (EthereumRelease option in options)
{
if (EthereumReleaseBlockStart.TryGetValue(option, out var blockNum))
{
if (state?.CurrentBlock?.Header?.BlockNumber >= blockNum && option > releaseType)
{
releaseType = option;
}
}
}
// Set our release type
Version = releaseType;
}
/// <summary>
/// Provides the cost of gas for a given
/// </summary>
/// <param name="currentVersion">The Ethereum release currently being executed.</param>
/// <param name="size">The size</param>
/// <returns></returns>
public static BigInteger GetMemoryCopyCost(EthereumRelease currentVersion, BigInteger size)
{
return(EVMDefinitions.GetWordCount(size) * GAS_MEMORY_COPY);
}
public OpcodeBaseGasCostAttribute(EthereumRelease version, uint baseGasCost)
{
Version = version;
BaseGasCost = baseGasCost;
}
/// <summary>
/// Obtains a release version's starting block number.
/// </summary>
/// <param name="releaseVersion">The release version to obtain the starting block number for (inclusive).</param>
/// <returns>Returns the block number which begins the release version provided.</returns>
public BigInteger GetReleaseStartBlockNumber(EthereumRelease releaseVersion)
{
return(EthereumReleaseBlockStart[releaseVersion]);
}
