diff options
Diffstat (limited to 'libsolidity/SolidityOptimizer.cpp')
| -rw-r--r-- | libsolidity/SolidityOptimizer.cpp | 118 |
1 files changed, 111 insertions, 7 deletions
diff --git a/libsolidity/SolidityOptimizer.cpp b/libsolidity/SolidityOptimizer.cpp index 9cdaa588..e50469dd 100644 --- a/libsolidity/SolidityOptimizer.cpp +++ b/libsolidity/SolidityOptimizer.cpp @@ -83,14 +83,28 @@ public: "\nOptimized: " + toHex(optimizedOutput)); } - AssemblyItems getCSE(AssemblyItems const& _input) + 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; + eth::CommonSubexpressionEliminator cse(_state); BOOST_REQUIRE(cse.feedItems(input.begin(), input.end()) == input.end()); AssemblyItems output = cse.getOptimizedItems(); @@ -101,9 +115,13 @@ public: return output; } - void checkCSE(AssemblyItems const& _input, AssemblyItems const& _expectation) + void checkCSE( + AssemblyItems const& _input, + AssemblyItems const& _expectation, + KnownState const& _state = eth::KnownState() + ) { - AssemblyItems output = getCSE(_input); + AssemblyItems output = getCSE(_input, _state); BOOST_CHECK_EQUAL_COLLECTIONS(_expectation.begin(), _expectation.end(), output.begin(), output.end()); } @@ -113,8 +131,12 @@ public: // Running it four times should be enough for these tests. for (unsigned i = 0; i < 4; ++i) { - eth::ControlFlowGraph cfg(output); - output = cfg.optimisedItems(); + 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); } BOOST_CHECK_EQUAL_COLLECTIONS(_expectation.begin(), _expectation.end(), output.begin(), output.end()); } @@ -229,9 +251,67 @@ BOOST_AUTO_TEST_CASE(function_calls) 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::CommonSubexpressionEliminator cse; + 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, @@ -754,6 +834,30 @@ BOOST_AUTO_TEST_CASE(cse_sha3_twice_same_content_noninterfering_store_in_between 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 |