diff options
Diffstat (limited to 'libsolidity/SolidityOptimizer.cpp')
| -rw-r--r-- | libsolidity/SolidityOptimizer.cpp | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/libsolidity/SolidityOptimizer.cpp b/libsolidity/SolidityOptimizer.cpp index 4ed081fd..3ac5f69e 100644 --- a/libsolidity/SolidityOptimizer.cpp +++ b/libsolidity/SolidityOptimizer.cpp @@ -908,6 +908,31 @@ BOOST_AUTO_TEST_CASE(cse_equality_on_initially_known_stack) BOOST_CHECK(find(output.begin(), output.end(), AssemblyItem(u256(1))) != output.end()); } +BOOST_AUTO_TEST_CASE(cse_access_previous_sequence) +{ + // Tests that the code generator detects whether it tries to access SLOAD instructions + // from a sequenced expression which is not in its scope. + eth::KnownState state = createInitialState(AssemblyItems{ + u256(0), + Instruction::SLOAD, + u256(1), + Instruction::ADD, + u256(0), + Instruction::SSTORE + }); + // now stored: val_1 + 1 (value at sequence 1) + // if in the following instructions, the SLOAD cresolves to "val_1 + 1", + // this cannot be generated because we cannot load from sequence 1 anymore. + AssemblyItems input{ + u256(0), + Instruction::SLOAD, + }; + BOOST_CHECK_THROW(getCSE(input, state), StackTooDeepException); + // @todo for now, this throws an exception, but it should recover to the following + // (or an even better version) at some point: + // 0, SLOAD, 1, ADD, SSTORE, 0 SLOAD +} + BOOST_AUTO_TEST_CASE(control_flow_graph_remove_unused) { // remove parts of the code that are unused |