private void Step()
{
// Verify we're not at the end of the stream
if (ExecutionState.PC >= Code.Length)
{
// If we reached the end, exit with the remainder of the gas and a success status.
ExecutionState.Result = new EVMExecutionResult(this, null, true);
return;
}
// Set our position back to the start of the instruction, grab our opcode and verify it.
InstructionOpcode opcode = (InstructionOpcode)Code.Span[(int)ExecutionState.PC];
// Obtain our base cost for this opcode. If we fail to, the instruction isn't implemented yet.
uint?instructionBaseGasCost = GasDefinitions.GetInstructionBaseGasCost(State.Configuration.Version, opcode);
if (instructionBaseGasCost == null)
{
throw new EVMException($"Invalid opcode {opcode.ToString()} read when executing!");
}
// If we just jumped, then this next opcode should be a JUMPDEST.
if (ExecutionState.JumpedLastInstruction && opcode != InstructionOpcode.JUMPDEST)
{
throw new EVMException($"Invalid jump to offset {ExecutionState.PC} in code!");
}
// Obtain our instruction implementation for this opcode
var opcodeDescriptor = opcode.GetDescriptor();
InstructionBase instruction = opcodeDescriptor.GetInstructionImplementation(this);
// Record our code coverage for this execution.
CoverageMap?.RecordExecution(instruction.Offset, (ExecutionState.PC - instruction.Offset));
// Record our instruction execution tracing
if (State.Configuration.DebugConfiguration.IsTracing)
{
State.Configuration.DebugConfiguration.ExecutionTrace?.RecordExecution(this, instruction, GasState.Gas, (BigInteger)instructionBaseGasCost);
}
// Deduct base gas cost
GasState.Deduct((BigInteger)instructionBaseGasCost);
// Debug: Print out instruction execution information.
//if (opcode == InstructionOpcode.JUMPDEST)
// Console.WriteLine($"\r\n---------------------------------------------------------------\r\n");
//Console.WriteLine($"0x{instruction.Offset.ToString("X4")}: {instruction}");
//Console.WriteLine($"Stack: {ExecutionState.Stack}");
// Execute the instruction
instruction.Execute();
}
public void TestBaseGasCostUpdates()
{
// Make static assertions about updates made during Tangerine Whistle release.
EthereumRelease[] releases = (EthereumRelease[])Enum.GetValues(typeof(EthereumRelease));
foreach (EthereumRelease release in releases)
{
if (release < EthereumRelease.TangerineWhistle)
{
Assert.Equal <uint>(20, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.BALANCE));
Assert.Equal <uint>(20, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.EXTCODESIZE));
Assert.Equal <uint>(20, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.EXTCODECOPY));
Assert.Equal <uint>(50, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.SLOAD));
Assert.Equal <uint>(40, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.CALL));
Assert.Equal <uint>(40, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.CALLCODE));
// DELEGATE CALL WAS INTRODUCED IN HOMESTEAD WITH 40 BASE GAS, NULL BEFORE.
if (release >= EthereumRelease.Homestead)
{
Assert.Equal <uint>(40, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.DELEGATECALL));
}
else
{
Assert.Null(GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.DELEGATECALL));
}
// STATIC CALL WAS INTRODUCED IN BYZANTIUM WITH 700 BASE GAS, NULL BEFORE
if (release >= EthereumRelease.Byzantium)
{
Assert.Equal <uint>(700, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.STATICCALL));
}
else
{
Assert.Null(GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.STATICCALL));
}
Assert.Equal <uint>(0, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.SELFDESTRUCT));
}
else
{
Assert.Equal <uint>(400, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.BALANCE));
Assert.Equal <uint>(700, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.EXTCODESIZE));
Assert.Equal <uint>(700, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.EXTCODECOPY));
Assert.Equal <uint>(200, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.SLOAD));
Assert.Equal <uint>(700, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.CALL));
Assert.Equal <uint>(700, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.CALLCODE));
Assert.Equal <uint>(700, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.DELEGATECALL));
Assert.Equal <uint>(5000, (uint)GasDefinitions.GetInstructionBaseGasCost(release, InstructionOpcode.SELFDESTRUCT));
}
}
}
