/*
This file is part of solidity.
solidity is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
solidity is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with solidity. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @author Christian <c@ethdev.com>
* @date 2015
* Unit tests for the gas estimator.
*/
#include <test/libsolidity/SolidityExecutionFramework.h>
#include <libevmasm/EVMSchedule.h>
#include <libevmasm/GasMeter.h>
#include <libevmasm/KnownState.h>
#include <libevmasm/PathGasMeter.h>
#include <libsolidity/ast/AST.h>
#include <libsolidity/interface/GasEstimator.h>
#include <libsolidity/interface/SourceReferenceFormatter.h>
using namespace std;
using namespace dev::eth;
using namespace dev::solidity;
using namespace dev::test;
namespace dev
{
namespace solidity
{
namespace test
{
class GasMeterTestFramework: public SolidityExecutionFramework
{
public:
GasMeterTestFramework() { }
void compile(string const& _sourceCode)
{
m_compiler.reset(false);
m_compiler.addSource("", "pragma solidity >=0.0;\n" + _sourceCode);
ETH_TEST_REQUIRE_NO_THROW(m_compiler.compile(dev::test::Options::get().optimize), "Compiling contract failed");
AssemblyItems const* items = m_compiler.runtimeAssemblyItems("");
ASTNode const& sourceUnit = m_compiler.ast();
BOOST_REQUIRE(items != nullptr);
m_gasCosts = GasEstimator::breakToStatementLevel(
GasEstimator::structuralEstimation(*items, vector<ASTNode const*>({&sourceUnit})),
{&sourceUnit}
);
}
void testCreationTimeGas(string const& _sourceCode)
{
EVMSchedule schedule;
compileAndRun(_sourceCode);
auto state = make_shared<KnownState>();
PathGasMeter meter(*m_compiler.assemblyItems());
GasMeter::GasConsumption gas = meter.estimateMax(0, state);
u256 bytecodeSize(m_compiler.runtimeObject().bytecode.size());
// costs for deployment
gas += bytecodeSize * schedule.createDataGas;
// costs for transaction
gas += gasForTransaction(m_compiler.object().bytecode, true);
BOOST_REQUIRE(!gas.isInfinite);
BOOST_CHECK(gas.value == m_gasUsed);
}
/// Compares the gas computed by PathGasMeter for the given signature (but unknown arguments)
/// against the actual gas usage computed by the VM on the given set of argument variants.
void testRunTimeGas(string const& _sig, vector<bytes> _argumentVariants)
{
u256 gasUsed = 0;
GasMeter::GasConsumption gas;
FixedHash<4> hash(dev::keccak256(_sig));
for (bytes const& arguments: _argumentVariants)
{
sendMessage(hash.asBytes() + arguments, false, 0);
gasUsed = max(gasUsed, m_gasUsed);
gas = max(gas, gasForTransaction(hash.asBytes() + arguments, false));
}
gas += GasEstimator::functionalEstimation(
*m_compiler.runtimeAssemblyItems(),
_sig
);
BOOST_REQUIRE(!gas.isInfinite);
BOOST_CHECK(gas.value == m_gasUsed);
}
static GasMeter::GasConsumption gasForTransaction(bytes const& _data, bool _isCreation)
{
EVMSchedule schedule;
GasMeter::GasConsumption gas = _isCreation ? schedule.txCreateGas : schedule.txGas;
for (auto i: _data)
gas += i != 0 ? schedule.txDataNonZeroGas : schedule.txDataZeroGas;
return gas;
}
protected:
map<ASTNode const*, eth::GasMeter::GasConsumption> m_gasCosts;
};
BOOST_FIXTURE_TEST_SUITE(GasMeterTests, GasMeterTestFramework)
BOOST_AUTO_TEST_CASE(non_overlapping_filtered_costs)
{
char const* sourceCode = R"(
contract test {
bytes x;
function f(uint a) returns (uint b) {
x.length = a;
for (; a < 200; ++a) {
x[a] = 9;
b = a * a;
}
return f(a - 1);
}
}
)";
compile(sourceCode);
for (auto first = m_gasCosts.cbegin(); first != m_gasCosts.cend(); ++first)
{
auto second = first;
for (++second; second != m_gasCosts.cend(); ++second)
if (first->first->location().intersects(second->first->location()))
{
BOOST_CHECK_MESSAGE(false, "Source locations should not overlap!");
auto scannerFromSource = [&](string const&) -> Scanner const& { return m_compiler.scanner(); };
SourceReferenceFormatter::printSourceLocation(cout, &first->first->location(), scannerFromSource);
SourceReferenceFormatter::printSourceLocation(cout, &second->first->location(), scannerFromSource);
}
}
}
BOOST_AUTO_TEST_CASE(simple_contract)
{
// Tests a simple "deploy contract" code without constructor. The actual contract is not relevant.
char const* sourceCode = R"(
contract test {
bytes32 public shaValue;
function f(uint a) {
shaValue = keccak256(a);
}
}
)";
testCreationTimeGas(sourceCode);
}
BOOST_AUTO_TEST_CASE(store_keccak256)
{
char const* sourceCode = R"(
contract test {
bytes32 public shaValue;
function test(uint a) {
shaValue = keccak256(a);
}
}
)";
testCreationTimeGas(sourceCode);
}
BOOST_AUTO_TEST_CASE(updating_store)
{
char const* sourceCode = R"(
contract test {
uint data;
uint data2;
function test() {
data = 1;
data = 2;
data2 = 0;
}
}
)";
testCreationTimeGas(sourceCode);
}
BOOST_AUTO_TEST_CASE(branches)
{
char const* sourceCode = R"(
contract test {
uint data;
uint data2;
function f(uint x) {
if (x > 7)
data2 = 1;
else
data = 1;
}
}
)";
testCreationTimeGas(sourceCode);
testRunTimeGas("f(uint256)", vector<bytes>{encodeArgs(2), encodeArgs(8)});
}
BOOST_AUTO_TEST_CASE(function_calls)
{
char const* sourceCode = R"(
contract test {
uint data;
uint data2;
function f(uint x) {
if (x > 7)
data2 = g(x**8) + 1;
else
data = 1;
}
function g(uint x) internal returns (uint) {
return data2;
}
}
)";
testCreationTimeGas(sourceCode);
testRunTimeGas("f(uint256)", vector<bytes>{encodeArgs(2), encodeArgs(8)});
}
BOOST_AUTO_TEST_CASE(multiple_external_functions)
{
char const* sourceCode = R"(
contract test {
uint data;
uint data2;
function f(uint x) {
if (x > 7)
data2 = g(x**8) + 1;
else
data = 1;
}
function g(uint x) returns (uint) {
return data2;
}
}
)";
testCreationTimeGas(sourceCode);
testRunTimeGas("f(uint256)", vector<bytes>{encodeArgs(2), encodeArgs(8)});
testRunTimeGas("g(uint256)", vector<bytes>{encodeArgs(2)});
}
BOOST_AUTO_TEST_CASE(exponent_size)
{
char const* sourceCode = R"(
contract A {
function g(uint x) returns (uint) {
return x ** 0x100;
}
function h(uint x) returns (uint) {
return x ** 0x10000;
}
}
)";
testCreationTimeGas(sourceCode);
testRunTimeGas("g(uint256)", vector<bytes>{encodeArgs(2)});
testRunTimeGas("h(uint256)", vector<bytes>{encodeArgs(2)});
}
BOOST_AUTO_TEST_CASE(balance_gas)
{
char const* sourceCode = R"(
contract A {
function lookup_balance(address a) returns (uint) {
return a.balance;
}
}
)";
testCreationTimeGas(sourceCode);
testRunTimeGas("lookup_balance(address)", vector<bytes>{encodeArgs(2), encodeArgs(100)});
}
BOOST_AUTO_TEST_CASE(extcodesize_gas)
{
char const* sourceCode = R"(
contract A {
function f() returns (uint _s) {
assembly {
_s := extcodesize(0x30)
}
}
}
)";
testCreationTimeGas(sourceCode);
testRunTimeGas("f()", vector<bytes>{encodeArgs()});
}
BOOST_AUTO_TEST_SUITE_END()
}
}
}
