diff --git a/Changelog.md b/Changelog.md index 4f224d5b1..68f2272d1 100644 --- a/Changelog.md +++ b/Changelog.md @@ -12,6 +12,7 @@ Features: * Inline Assembly: introduce ``keccak256`` as an opcode. ``sha3`` is still a valid alias. * Inline Assembly: ``for`` and ``switch`` statements. * Inline Assembly: function definitions and function calls. + * Inline Assembly: Warn when using ``jump``s. * Type Checker: Warn about copies in storage that might overwrite unexpectedly. * Code Generator: Added the Whiskers template system. * Remove obsolete Why3 output. diff --git a/libsolidity/inlineasm/AsmAnalysis.cpp b/libsolidity/inlineasm/AsmAnalysis.cpp index b0d044ae3..7e00ffaec 100644 --- a/libsolidity/inlineasm/AsmAnalysis.cpp +++ b/libsolidity/inlineasm/AsmAnalysis.cpp @@ -65,7 +65,7 @@ bool AsmAnalyzer::operator()(assembly::Instruction const& _instruction) auto const& info = instructionInfo(_instruction.instruction); m_stackHeight += info.ret - info.args; m_info.stackHeightInfo[&_instruction] = m_stackHeight; - warnOnFutureInstruction(_instruction.instruction, _instruction.location); + warnOnInstructions(_instruction.instruction, _instruction.location); return true; } @@ -150,7 +150,6 @@ bool AsmAnalyzer::operator()(FunctionalInstruction const& _instr) if (!(*this)(_instr.instruction)) success = false; m_info.stackHeightInfo[&_instr] = m_stackHeight; - warnOnFutureInstruction(_instr.instruction.instruction, _instr.location); return success; } @@ -470,7 +469,7 @@ void AsmAnalyzer::expectValidType(string const& type, SourceLocation const& _loc ); } -void AsmAnalyzer::warnOnFutureInstruction(solidity::Instruction _instr, SourceLocation const& _location) +void AsmAnalyzer::warnOnInstructions(solidity::Instruction _instr, SourceLocation const& _location) { static set futureInstructions{ solidity::Instruction::CREATE2, @@ -486,4 +485,12 @@ void AsmAnalyzer::warnOnFutureInstruction(solidity::Instruction _instr, SourceLo + "\" instruction is only available after " + "the Metropolis hard fork. Before that it acts as an invalid instruction." ); + + if (_instr == solidity::Instruction::JUMP || _instr == solidity::Instruction::JUMPI) + m_errorReporter.warning( + _location, + "Jump instructions are low-level EVM features that can lead to " + "incorrect stack access. Because of that they are discouraged. " + "Please consider using \"switch\" or \"for\" statements instead." + ); } diff --git a/libsolidity/inlineasm/AsmAnalysis.h b/libsolidity/inlineasm/AsmAnalysis.h index 76d2eba1a..9b2a8f9c7 100644 --- a/libsolidity/inlineasm/AsmAnalysis.h +++ b/libsolidity/inlineasm/AsmAnalysis.h @@ -85,7 +85,7 @@ private: Scope& scope(assembly::Block const* _block); void expectValidType(std::string const& type, SourceLocation const& _location); - void warnOnFutureInstruction(solidity::Instruction _instr, SourceLocation const& _location); + void warnOnInstructions(solidity::Instruction _instr, SourceLocation const& _location); int m_stackHeight = 0; julia::ExternalIdentifierAccess::Resolver m_resolver; diff --git a/test/libsolidity/InlineAssembly.cpp b/test/libsolidity/InlineAssembly.cpp index 7b760a1d0..5197f649f 100644 --- a/test/libsolidity/InlineAssembly.cpp +++ b/test/libsolidity/InlineAssembly.cpp @@ -67,23 +67,19 @@ boost::optional parseAndReturnFirstError( BOOST_FAIL("Fatal error leaked."); success = false; } + shared_ptr error; + for (auto const& e: stack.errors()) + { + if (_allowWarnings && e->type() == Error::Type::Warning) + continue; + if (error) + BOOST_FAIL("Found more than one error."); + error = e; + } if (!success) - { - BOOST_REQUIRE_EQUAL(stack.errors().size(), 1); - return *stack.errors().front(); - } - else - { - // If success is true, there might still be an error in the assembly stage. - if (_allowWarnings && Error::containsOnlyWarnings(stack.errors())) - return {}; - else if (!stack.errors().empty()) - { - if (!_allowWarnings) - BOOST_CHECK_EQUAL(stack.errors().size(), 1); - return *stack.errors().front(); - } - } + BOOST_REQUIRE(error); + if (error) + return *error; return {}; } @@ -111,29 +107,35 @@ Error expectError(std::string const& _source, bool _assemble, bool _allowWarning return *error; } -void parsePrintCompare(string const& _source) +void parsePrintCompare(string const& _source, bool _canWarn = false) { AssemblyStack stack; BOOST_REQUIRE(stack.parseAndAnalyze("", _source)); - BOOST_REQUIRE(stack.errors().empty()); + if (_canWarn) + BOOST_REQUIRE(Error::containsOnlyWarnings(stack.errors())); + else + BOOST_REQUIRE(stack.errors().empty()); BOOST_CHECK_EQUAL(stack.print(), _source); } } -#define CHECK_ERROR(text, assemble, typ, substring) \ +#define CHECK_ERROR(text, assemble, typ, substring, warnings) \ do \ { \ - Error err = expectError((text), (assemble), false); \ + Error err = expectError((text), (assemble), warnings); \ BOOST_CHECK(err.type() == (Error::Type::typ)); \ BOOST_CHECK(searchErrorMessage(err, (substring))); \ } while(0) #define CHECK_PARSE_ERROR(text, type, substring) \ -CHECK_ERROR(text, false, type, substring) +CHECK_ERROR(text, false, type, substring, false) + +#define CHECK_PARSE_WARNING(text, type, substring) \ +CHECK_ERROR(text, false, type, substring, false) #define CHECK_ASSEMBLE_ERROR(text, type, substring) \ -CHECK_ERROR(text, true, type, substring) +CHECK_ERROR(text, true, type, substring, false) @@ -411,7 +413,7 @@ BOOST_AUTO_TEST_CASE(print_functional) BOOST_AUTO_TEST_CASE(print_label) { - parsePrintCompare("{\n loop:\n jump(loop)\n}"); + parsePrintCompare("{\n loop:\n jump(loop)\n}", true); } BOOST_AUTO_TEST_CASE(print_assignments) @@ -515,7 +517,7 @@ BOOST_AUTO_TEST_CASE(imbalanced_stack) BOOST_AUTO_TEST_CASE(error_tag) { - CHECK_ASSEMBLE_ERROR("{ jump(invalidJumpLabel) }", DeclarationError, "Identifier not found"); + CHECK_ERROR("{ jump(invalidJumpLabel) }", true, DeclarationError, "Identifier not found", true); } BOOST_AUTO_TEST_CASE(designated_invalid_instruction) @@ -630,6 +632,14 @@ BOOST_AUTO_TEST_CASE(create2) BOOST_CHECK(successAssemble("{ pop(create2(10, 0x123, 32, 64)) }")); } +BOOST_AUTO_TEST_CASE(jump_warning) +{ + CHECK_PARSE_WARNING("{ 1 jump }", Warning, "Jump instructions"); + CHECK_PARSE_WARNING("{ 1 2 jumpi }", Warning, "Jump instructions"); + CHECK_PARSE_WARNING("{ a: jump(a) }", Warning, "Jump instructions"); + CHECK_PARSE_WARNING("{ a: jumpi(a, 2) }", Warning, "Jump instructions"); +} + BOOST_AUTO_TEST_SUITE_END() BOOST_AUTO_TEST_SUITE_END()