solidity/libsolidity/SolidityOptimizer.cpp
2015-05-12 16:27:43 +02:00

969 lines
23 KiB
C++

/*
This file is part of cpp-ethereum.
cpp-ethereum 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.
cpp-ethereum 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 cpp-ethereum. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @author Christian <c@ethdev.com>
* @date 2014
* Tests for the Solidity optimizer.
*/
#include <string>
#include <tuple>
#include <memory>
#include <boost/test/unit_test.hpp>
#include <boost/lexical_cast.hpp>
#include <test/libsolidity/solidityExecutionFramework.h>
#include <libevmasm/CommonSubexpressionEliminator.h>
#include <libevmasm/ControlFlowGraph.h>
#include <libevmasm/Assembly.h>
#include <libevmasm/BlockDeduplicator.h>
using namespace std;
using namespace dev::eth;
namespace dev
{
namespace solidity
{
namespace test
{
class OptimizerTestFramework: public ExecutionFramework
{
public:
OptimizerTestFramework() { }
/// Compiles the source code with and without optimizing.
void compileBothVersions(
std::string const& _sourceCode,
u256 const& _value = 0,
std::string const& _contractName = ""
)
{
m_optimize = false;
bytes nonOptimizedBytecode = compileAndRun(_sourceCode, _value, _contractName);
m_nonOptimizedContract = m_contractAddress;
m_optimize = true;
bytes optimizedBytecode = compileAndRun(_sourceCode, _value, _contractName);
size_t nonOptimizedSize = 0;
eth::eachInstruction(nonOptimizedBytecode, [&](Instruction, u256 const&) {
nonOptimizedSize++;
});
size_t optimizedSize = 0;
eth::eachInstruction(optimizedBytecode, [&](Instruction, u256 const&) {
optimizedSize++;
});
BOOST_CHECK_MESSAGE(
nonOptimizedSize > optimizedSize,
"Optimizer did not reduce bytecode size."
);
m_optimizedContract = m_contractAddress;
}
template <class... Args>
void compareVersions(std::string _sig, Args const&... _arguments)
{
m_contractAddress = m_nonOptimizedContract;
bytes nonOptimizedOutput = callContractFunction(_sig, _arguments...);
m_contractAddress = m_optimizedContract;
bytes optimizedOutput = callContractFunction(_sig, _arguments...);
BOOST_CHECK_MESSAGE(nonOptimizedOutput == optimizedOutput, "Computed values do not match."
"\nNon-Optimized: " + toHex(nonOptimizedOutput) +
"\nOptimized: " + toHex(optimizedOutput));
}
AssemblyItems addDummyLocations(AssemblyItems const& _input)
{
// add dummy locations to each item so that we can check that they are not deleted
AssemblyItems input = _input;
for (AssemblyItem& item: input)
item.setLocation(SourceLocation(1, 3, make_shared<string>("")));
return input;
}
eth::KnownState createInitialState(AssemblyItems const& _input)
{
eth::KnownState state;
for (auto const& item: addDummyLocations(_input))
state.feedItem(item);
return state;
}
AssemblyItems getCSE(AssemblyItems const& _input, eth::KnownState const& _state = eth::KnownState())
{
AssemblyItems input = addDummyLocations(_input);
eth::CommonSubexpressionEliminator cse(_state);
BOOST_REQUIRE(cse.feedItems(input.begin(), input.end()) == input.end());
AssemblyItems output = cse.getOptimizedItems();
for (AssemblyItem const& item: output)
{
BOOST_CHECK(item == Instruction::POP || !item.getLocation().isEmpty());
}
return output;
}
void checkCSE(
AssemblyItems const& _input,
AssemblyItems const& _expectation,
KnownState const& _state = eth::KnownState()
)
{
AssemblyItems output = getCSE(_input, _state);
BOOST_CHECK_EQUAL_COLLECTIONS(_expectation.begin(), _expectation.end(), output.begin(), output.end());
}
AssemblyItems getCFG(AssemblyItems const& _input)
{
AssemblyItems output = _input;
// Running it four times should be enough for these tests.
for (unsigned i = 0; i < 4; ++i)
{
ControlFlowGraph cfg(output);
AssemblyItems optItems;
for (BasicBlock const& block: cfg.optimisedBlocks())
copy(output.begin() + block.begin, output.begin() + block.end,
back_inserter(optItems));
output = move(optItems);
}
return output;
}
void checkCFG(AssemblyItems const& _input, AssemblyItems const& _expectation)
{
AssemblyItems output = getCFG(_input);
BOOST_CHECK_EQUAL_COLLECTIONS(_expectation.begin(), _expectation.end(), output.begin(), output.end());
}
protected:
Address m_optimizedContract;
Address m_nonOptimizedContract;
};
BOOST_FIXTURE_TEST_SUITE(SolidityOptimizer, OptimizerTestFramework)
BOOST_AUTO_TEST_CASE(smoke_test)
{
char const* sourceCode = R"(
contract test {
function f(uint a) returns (uint b) {
return a;
}
})";
compileBothVersions(sourceCode);
compareVersions("f(uint256)", u256(7));
}
BOOST_AUTO_TEST_CASE(identities)
{
char const* sourceCode = R"(
contract test {
function f(int a) returns (int b) {
return int(0) | (int(1) * (int(0) ^ (0 + a)));
}
})";
compileBothVersions(sourceCode);
compareVersions("f(uint256)", u256(0x12334664));
}
BOOST_AUTO_TEST_CASE(unused_expressions)
{
char const* sourceCode = R"(
contract test {
uint data;
function f() returns (uint a, uint b) {
10 + 20;
data;
}
})";
compileBothVersions(sourceCode);
compareVersions("f()");
}
BOOST_AUTO_TEST_CASE(constant_folding_both_sides)
{
// if constants involving the same associative and commutative operator are applied from both
// sides, the operator should be applied only once, because the expression compiler pushes
// literals as late as possible
char const* sourceCode = R"(
contract test {
function f(uint x) returns (uint y) {
return 98 ^ (7 * ((1 | (x | 1000)) * 40) ^ 102);
}
})";
compileBothVersions(sourceCode);
compareVersions("f(uint256)");
}
BOOST_AUTO_TEST_CASE(storage_access)
{
char const* sourceCode = R"(
contract test {
uint8[40] data;
function f(uint x) returns (uint y) {
data[2] = data[7] = uint8(x);
data[4] = data[2] * 10 + data[3];
}
}
)";
compileBothVersions(sourceCode);
compareVersions("f(uint256)");
}
BOOST_AUTO_TEST_CASE(array_copy)
{
char const* sourceCode = R"(
contract test {
bytes2[] data1;
bytes5[] data2;
function f(uint x) returns (uint l, uint y) {
for (uint i = 0; i < msg.data.length; ++i)
data1[i] = msg.data[i];
data2 = data1;
l = data2.length;
y = uint(data2[x]);
}
}
)";
compileBothVersions(sourceCode);
compareVersions("f(uint256)", 0);
compareVersions("f(uint256)", 10);
compareVersions("f(uint256)", 36);
}
BOOST_AUTO_TEST_CASE(function_calls)
{
char const* sourceCode = R"(
contract test {
function f1(uint x) returns (uint) { return x*x; }
function f(uint x) returns (uint) { return f1(7+x) - this.f1(x**9); }
}
)";
compileBothVersions(sourceCode);
compareVersions("f(uint256)", 0);
compareVersions("f(uint256)", 10);
compareVersions("f(uint256)", 36);
}
BOOST_AUTO_TEST_CASE(storage_write_in_loops)
{
char const* sourceCode = R"(
contract test {
uint d;
function f(uint a) returns (uint r) {
var x = d;
for (uint i = 1; i < a * a; i++) {
r = d;
d = i;
}
}
}
)";
compileBothVersions(sourceCode);
compareVersions("f(uint256)", 0);
compareVersions("f(uint256)", 10);
compareVersions("f(uint256)", 36);
}
BOOST_AUTO_TEST_CASE(retain_information_in_branches)
{
// This tests that the optimizer knows that we already have "z == sha3(y)" inside both branches.
char const* sourceCode = R"(
contract c {
bytes32 d;
uint a;
function f(uint x, bytes32 y) returns (uint r_a, bytes32 r_d) {
bytes32 z = sha3(y);
if (x > 8) {
z = sha3(y);
a = x;
} else {
z = sha3(y);
a = x;
}
r_a = a;
r_d = d;
}
}
)";
compileBothVersions(sourceCode);
compareVersions("f(uint256,bytes32)", 0, "abc");
compareVersions("f(uint256,bytes32)", 8, "def");
compareVersions("f(uint256,bytes32)", 10, "ghi");
m_optimize = true;
bytes optimizedBytecode = compileAndRun(sourceCode, 0, "c");
size_t numSHA3s = 0;
eth::eachInstruction(optimizedBytecode, [&](Instruction _instr, u256 const&) {
if (_instr == eth::Instruction::SHA3)
numSHA3s++;
});
BOOST_CHECK_EQUAL(1, numSHA3s);
}
BOOST_AUTO_TEST_CASE(cse_intermediate_swap)
{
eth::KnownState state;
eth::CommonSubexpressionEliminator cse(state);
AssemblyItems input{
Instruction::SWAP1, Instruction::POP, Instruction::ADD, u256(0), Instruction::SWAP1,
Instruction::SLOAD, Instruction::SWAP1, u256(100), Instruction::EXP, Instruction::SWAP1,
Instruction::DIV, u256(0xff), Instruction::AND
};
BOOST_REQUIRE(cse.feedItems(input.begin(), input.end()) == input.end());
AssemblyItems output = cse.getOptimizedItems();
BOOST_CHECK(!output.empty());
}
BOOST_AUTO_TEST_CASE(cse_negative_stack_access)
{
AssemblyItems input{Instruction::DUP2, u256(0)};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_negative_stack_end)
{
AssemblyItems input{Instruction::ADD};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_intermediate_negative_stack)
{
AssemblyItems input{Instruction::ADD, u256(1), Instruction::DUP1};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_pop)
{
checkCSE({Instruction::POP}, {Instruction::POP});
}
BOOST_AUTO_TEST_CASE(cse_unneeded_items)
{
AssemblyItems input{
Instruction::ADD,
Instruction::SWAP1,
Instruction::POP,
u256(7),
u256(8),
};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_constant_addition)
{
AssemblyItems input{u256(7), u256(8), Instruction::ADD};
checkCSE(input, {u256(7 + 8)});
}
BOOST_AUTO_TEST_CASE(cse_invariants)
{
AssemblyItems input{
Instruction::DUP1,
Instruction::DUP1,
u256(0),
Instruction::OR,
Instruction::OR
};
checkCSE(input, {Instruction::DUP1});
}
BOOST_AUTO_TEST_CASE(cse_subself)
{
checkCSE({Instruction::DUP1, Instruction::SUB}, {Instruction::POP, u256(0)});
}
BOOST_AUTO_TEST_CASE(cse_subother)
{
checkCSE({Instruction::SUB}, {Instruction::SUB});
}
BOOST_AUTO_TEST_CASE(cse_double_negation)
{
checkCSE({Instruction::DUP5, Instruction::NOT, Instruction::NOT}, {Instruction::DUP5});
}
BOOST_AUTO_TEST_CASE(cse_associativity)
{
AssemblyItems input{
Instruction::DUP1,
Instruction::DUP1,
u256(0),
Instruction::OR,
Instruction::OR
};
checkCSE(input, {Instruction::DUP1});
}
BOOST_AUTO_TEST_CASE(cse_associativity2)
{
AssemblyItems input{
u256(0),
Instruction::DUP2,
u256(2),
u256(1),
Instruction::DUP6,
Instruction::ADD,
u256(2),
Instruction::ADD,
Instruction::ADD,
Instruction::ADD,
Instruction::ADD
};
checkCSE(input, {Instruction::DUP2, Instruction::DUP2, Instruction::ADD, u256(5), Instruction::ADD});
}
BOOST_AUTO_TEST_CASE(cse_storage)
{
AssemblyItems input{
u256(0),
Instruction::SLOAD,
u256(0),
Instruction::SLOAD,
Instruction::ADD,
u256(0),
Instruction::SSTORE
};
checkCSE(input, {
u256(0),
Instruction::DUP1,
Instruction::SLOAD,
Instruction::DUP1,
Instruction::ADD,
Instruction::SWAP1,
Instruction::SSTORE
});
}
BOOST_AUTO_TEST_CASE(cse_noninterleaved_storage)
{
// two stores to the same location should be replaced by only one store, even if we
// read in the meantime
AssemblyItems input{
u256(7),
Instruction::DUP2,
Instruction::SSTORE,
Instruction::DUP1,
Instruction::SLOAD,
u256(8),
Instruction::DUP3,
Instruction::SSTORE
};
checkCSE(input, {
u256(8),
Instruction::DUP2,
Instruction::SSTORE,
u256(7)
});
}
BOOST_AUTO_TEST_CASE(cse_interleaved_storage)
{
// stores and reads to/from two unknown locations, should not optimize away the first store
AssemblyItems input{
u256(7),
Instruction::DUP2,
Instruction::SSTORE, // store to "DUP1"
Instruction::DUP2,
Instruction::SLOAD, // read from "DUP2", might be equal to "DUP1"
u256(0),
Instruction::DUP3,
Instruction::SSTORE // store different value to "DUP1"
};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_interleaved_storage_same_value)
{
// stores and reads to/from two unknown locations, should not optimize away the first store
// but it should optimize away the second, since we already know the value will be the same
AssemblyItems input{
u256(7),
Instruction::DUP2,
Instruction::SSTORE, // store to "DUP1"
Instruction::DUP2,
Instruction::SLOAD, // read from "DUP2", might be equal to "DUP1"
u256(6),
u256(1),
Instruction::ADD,
Instruction::DUP3,
Instruction::SSTORE // store same value to "DUP1"
};
checkCSE(input, {
u256(7),
Instruction::DUP2,
Instruction::SSTORE,
Instruction::DUP2,
Instruction::SLOAD
});
}
BOOST_AUTO_TEST_CASE(cse_interleaved_storage_at_known_location)
{
// stores and reads to/from two known locations, should optimize away the first store,
// because we know that the location is different
AssemblyItems input{
u256(0x70),
u256(1),
Instruction::SSTORE, // store to 1
u256(2),
Instruction::SLOAD, // read from 2, is different from 1
u256(0x90),
u256(1),
Instruction::SSTORE // store different value at 1
};
checkCSE(input, {
u256(2),
Instruction::SLOAD,
u256(0x90),
u256(1),
Instruction::SSTORE
});
}
BOOST_AUTO_TEST_CASE(cse_interleaved_storage_at_known_location_offset)
{
// stores and reads to/from two locations which are known to be different,
// should optimize away the first store, because we know that the location is different
AssemblyItems input{
u256(0x70),
Instruction::DUP2,
u256(1),
Instruction::ADD,
Instruction::SSTORE, // store to "DUP1"+1
Instruction::DUP1,
u256(2),
Instruction::ADD,
Instruction::SLOAD, // read from "DUP1"+2, is different from "DUP1"+1
u256(0x90),
Instruction::DUP3,
u256(1),
Instruction::ADD,
Instruction::SSTORE // store different value at "DUP1"+1
};
checkCSE(input, {
u256(2),
Instruction::DUP2,
Instruction::ADD,
Instruction::SLOAD,
u256(0x90),
u256(1),
Instruction::DUP4,
Instruction::ADD,
Instruction::SSTORE
});
}
BOOST_AUTO_TEST_CASE(cse_interleaved_memory_at_known_location_offset)
{
// stores and reads to/from two locations which are known to be different,
// should not optimize away the first store, because the location overlaps with the load,
// but it should optimize away the second, because we know that the location is different by 32
AssemblyItems input{
u256(0x50),
Instruction::DUP2,
u256(2),
Instruction::ADD,
Instruction::MSTORE, // ["DUP1"+2] = 0x50
u256(0x60),
Instruction::DUP2,
u256(32),
Instruction::ADD,
Instruction::MSTORE, // ["DUP1"+32] = 0x60
Instruction::DUP1,
Instruction::MLOAD, // read from "DUP1"
u256(0x70),
Instruction::DUP3,
u256(32),
Instruction::ADD,
Instruction::MSTORE, // ["DUP1"+32] = 0x70
u256(0x80),
Instruction::DUP3,
u256(2),
Instruction::ADD,
Instruction::MSTORE, // ["DUP1"+2] = 0x80
};
// If the actual code changes too much, we could also simply check that the output contains
// exactly 3 MSTORE and exactly 1 MLOAD instruction.
checkCSE(input, {
u256(0x50),
u256(2),
Instruction::DUP3,
Instruction::ADD,
Instruction::SWAP1,
Instruction::DUP2,
Instruction::MSTORE, // ["DUP1"+2] = 0x50
Instruction::DUP2,
Instruction::MLOAD, // read from "DUP1"
u256(0x70),
u256(32),
Instruction::DUP5,
Instruction::ADD,
Instruction::MSTORE, // ["DUP1"+32] = 0x70
u256(0x80),
Instruction::SWAP1,
Instruction::SWAP2,
Instruction::MSTORE // ["DUP1"+2] = 0x80
});
}
BOOST_AUTO_TEST_CASE(cse_deep_stack)
{
AssemblyItems input{
Instruction::ADD,
Instruction::SWAP1,
Instruction::POP,
Instruction::SWAP8,
Instruction::POP,
Instruction::SWAP8,
Instruction::POP,
Instruction::SWAP8,
Instruction::SWAP5,
Instruction::POP,
Instruction::POP,
Instruction::POP,
Instruction::POP,
Instruction::POP,
};
checkCSE(input, {
Instruction::SWAP4,
Instruction::SWAP12,
Instruction::SWAP3,
Instruction::SWAP11,
Instruction::POP,
Instruction::SWAP1,
Instruction::SWAP3,
Instruction::ADD,
Instruction::SWAP8,
Instruction::POP,
Instruction::SWAP6,
Instruction::POP,
Instruction::POP,
Instruction::POP,
Instruction::POP,
Instruction::POP,
Instruction::POP,
});
}
BOOST_AUTO_TEST_CASE(cse_jumpi_no_jump)
{
AssemblyItems input{
u256(0),
u256(1),
Instruction::DUP2,
AssemblyItem(PushTag, 1),
Instruction::JUMPI
};
checkCSE(input, {
u256(0),
u256(1)
});
}
BOOST_AUTO_TEST_CASE(cse_jumpi_jump)
{
AssemblyItems input{
u256(1),
u256(1),
Instruction::DUP2,
AssemblyItem(PushTag, 1),
Instruction::JUMPI
};
checkCSE(input, {
u256(1),
Instruction::DUP1,
AssemblyItem(PushTag, 1),
Instruction::JUMP
});
}
BOOST_AUTO_TEST_CASE(cse_empty_sha3)
{
AssemblyItems input{
u256(0),
Instruction::DUP2,
Instruction::SHA3
};
checkCSE(input, {
u256(sha3(bytesConstRef()))
});
}
BOOST_AUTO_TEST_CASE(cse_partial_sha3)
{
AssemblyItems input{
u256(0xabcd) << (256 - 16),
u256(0),
Instruction::MSTORE,
u256(2),
u256(0),
Instruction::SHA3
};
checkCSE(input, {
u256(0xabcd) << (256 - 16),
u256(0),
Instruction::MSTORE,
u256(sha3(bytes{0xab, 0xcd}))
});
}
BOOST_AUTO_TEST_CASE(cse_sha3_twice_same_location)
{
// sha3 twice from same dynamic location
AssemblyItems input{
Instruction::DUP2,
Instruction::DUP1,
Instruction::MSTORE,
u256(64),
Instruction::DUP2,
Instruction::SHA3,
u256(64),
Instruction::DUP3,
Instruction::SHA3
};
checkCSE(input, {
Instruction::DUP2,
Instruction::DUP1,
Instruction::MSTORE,
u256(64),
Instruction::DUP2,
Instruction::SHA3,
Instruction::DUP1
});
}
BOOST_AUTO_TEST_CASE(cse_sha3_twice_same_content)
{
// sha3 twice from different dynamic location but with same content
AssemblyItems input{
Instruction::DUP1,
u256(0x80),
Instruction::MSTORE, // m[128] = DUP1
u256(0x20),
u256(0x80),
Instruction::SHA3, // sha3(m[128..(128+32)])
Instruction::DUP2,
u256(12),
Instruction::MSTORE, // m[12] = DUP1
u256(0x20),
u256(12),
Instruction::SHA3 // sha3(m[12..(12+32)])
};
checkCSE(input, {
u256(0x80),
Instruction::DUP2,
Instruction::DUP2,
Instruction::MSTORE,
u256(0x20),
Instruction::SWAP1,
Instruction::SHA3,
u256(12),
Instruction::DUP3,
Instruction::SWAP1,
Instruction::MSTORE,
Instruction::DUP1
});
}
BOOST_AUTO_TEST_CASE(cse_sha3_twice_same_content_dynamic_store_in_between)
{
// sha3 twice from different dynamic location but with same content,
// dynamic mstore in between, which forces us to re-calculate the sha3
AssemblyItems input{
u256(0x80),
Instruction::DUP2,
Instruction::DUP2,
Instruction::MSTORE, // m[128] = DUP1
u256(0x20),
Instruction::DUP1,
Instruction::DUP3,
Instruction::SHA3, // sha3(m[128..(128+32)])
u256(12),
Instruction::DUP5,
Instruction::DUP2,
Instruction::MSTORE, // m[12] = DUP1
Instruction::DUP12,
Instruction::DUP14,
Instruction::MSTORE, // destroys memory knowledge
Instruction::SWAP2,
Instruction::SWAP1,
Instruction::SWAP2,
Instruction::SHA3 // sha3(m[12..(12+32)])
};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_sha3_twice_same_content_noninterfering_store_in_between)
{
// sha3 twice from different dynamic location but with same content,
// dynamic mstore in between, but does not force us to re-calculate the sha3
AssemblyItems input{
u256(0x80),
Instruction::DUP2,
Instruction::DUP2,
Instruction::MSTORE, // m[128] = DUP1
u256(0x20),
Instruction::DUP1,
Instruction::DUP3,
Instruction::SHA3, // sha3(m[128..(128+32)])
u256(12),
Instruction::DUP5,
Instruction::DUP2,
Instruction::MSTORE, // m[12] = DUP1
Instruction::DUP12,
u256(12 + 32),
Instruction::MSTORE, // does not destoy memory knowledge
Instruction::DUP13,
u256(128 - 32),
Instruction::MSTORE, // does not destoy memory knowledge
u256(0x20),
u256(12),
Instruction::SHA3 // sha3(m[12..(12+32)])
};
// if this changes too often, only count the number of SHA3 and MSTORE instructions
AssemblyItems output = getCSE(input);
BOOST_CHECK_EQUAL(4, count(output.begin(), output.end(), AssemblyItem(Instruction::MSTORE)));
BOOST_CHECK_EQUAL(1, count(output.begin(), output.end(), AssemblyItem(Instruction::SHA3)));
}
BOOST_AUTO_TEST_CASE(cse_with_initially_known_stack)
{
eth::KnownState state = createInitialState(AssemblyItems{
u256(0x12),
u256(0x20),
Instruction::ADD
});
AssemblyItems input{
u256(0x12 + 0x20)
};
checkCSE(input, AssemblyItems{Instruction::DUP1}, state);
}
BOOST_AUTO_TEST_CASE(cse_equality_on_initially_known_stack)
{
eth::KnownState state = createInitialState(AssemblyItems{Instruction::DUP1});
AssemblyItems input{
Instruction::EQ
};
AssemblyItems output = getCSE(input, state);
// check that it directly pushes 1 (true)
BOOST_CHECK(find(output.begin(), output.end(), AssemblyItem(u256(1))) != output.end());
}
BOOST_AUTO_TEST_CASE(control_flow_graph_remove_unused)
{
// remove parts of the code that are unused
AssemblyItems input{
AssemblyItem(PushTag, 1),
Instruction::JUMP,
u256(7),
AssemblyItem(Tag, 1),
};
checkCFG(input, {});
}
BOOST_AUTO_TEST_CASE(control_flow_graph_remove_unused_loop)
{
AssemblyItems input{
AssemblyItem(PushTag, 3),
Instruction::JUMP,
AssemblyItem(Tag, 1),
u256(7),
AssemblyItem(PushTag, 2),
Instruction::JUMP,
AssemblyItem(Tag, 2),
u256(8),
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 3),
u256(11)
};
checkCFG(input, {u256(11)});
}
BOOST_AUTO_TEST_CASE(control_flow_graph_reconnect_single_jump_source)
{
// move code that has only one unconditional jump source
AssemblyItems input{
u256(1),
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 2),
u256(2),
AssemblyItem(PushTag, 3),
Instruction::JUMP,
AssemblyItem(Tag, 1),
u256(3),
AssemblyItem(PushTag, 2),
Instruction::JUMP,
AssemblyItem(Tag, 3),
u256(4),
};
checkCFG(input, {u256(1), u256(3), u256(2), u256(4)});
}
BOOST_AUTO_TEST_CASE(control_flow_graph_do_not_remove_returned_to)
{
// do not remove parts that are "returned to"
AssemblyItems input{
AssemblyItem(PushTag, 1),
AssemblyItem(PushTag, 2),
Instruction::JUMP,
AssemblyItem(Tag, 2),
Instruction::JUMP,
AssemblyItem(Tag, 1),
u256(2)
};
checkCFG(input, {u256(2)});
}
BOOST_AUTO_TEST_CASE(block_deduplicator)
{
AssemblyItems input{
AssemblyItem(PushTag, 2),
AssemblyItem(PushTag, 1),
AssemblyItem(PushTag, 3),
u256(6),
eth::Instruction::SWAP3,
eth::Instruction::JUMP,
AssemblyItem(Tag, 1),
u256(6),
eth::Instruction::SWAP3,
eth::Instruction::JUMP,
AssemblyItem(Tag, 2),
u256(6),
eth::Instruction::SWAP3,
eth::Instruction::JUMP,
AssemblyItem(Tag, 3)
};
BlockDeduplicator dedup(input);
dedup.deduplicate();
set<u256> pushTags;
for (AssemblyItem const& item: input)
if (item.type() == PushTag)
pushTags.insert(item.data());
BOOST_CHECK_EQUAL(pushTags.size(), 2);
}
BOOST_AUTO_TEST_SUITE_END()
}
}
} // end namespaces