Remove EWASM backend.

Author: aarlt

Changelog.md

@@ -4,6 +4,7 @@ Language Features:
 
 
 Compiler Features:
+ * EWasm: Remove EWasm backend.
 
 
 Bugfixes:

cmake/templates/ewasm_polyfill.in

@@ -93,8 +93,7 @@ Prerequisites
 
 For running all compiler tests you may want to optionally install a few
 dependencies (`evmone <https://github.com/ethereum/evmone/releases>`_,
-`libz3 <https://github.com/Z3Prover/z3>`_, and
-`libhera <https://github.com/ewasm/hera>`_).
+`libz3 <https://github.com/Z3Prover/z3>`_).
 
 On macOS systems, some of the testing scripts expect GNU coreutils to be installed.
 This can be easiest accomplished using Homebrew: ``brew install coreutils``.
@@ -129,13 +128,7 @@ for the ``evmone`` shared object can be specified via the ``ETH_EVMONE`` environ
 If you do not have it installed, you can skip these tests by passing the ``--no-semantic-tests``
 flag to ``scripts/soltest.sh``.
 
-Running Ewasm tests is disabled by default and can be explicitly enabled
-via ``./scripts/soltest.sh --ewasm`` and requires `hera <https://github.com/ewasm/hera>`_
-to be found by ``soltest``.
-The mechanism for locating the ``hera`` library is the same as for ``evmone``, except that the
-variable for specifying an explicit location is called ``ETH_HERA``.
-
-The ``evmone`` and ``hera`` libraries should both end with the file name
+The ``evmone`` library should both end with the file name
 extension ``.so`` on Linux, ``.dll`` on Windows systems and ``.dylib`` on macOS.
 
 For running SMT tests, the ``libz3`` library must be installed and locatable

docs/contributing.rst

@@ -404,10 +404,8 @@ Input Description
         //   evm.deployedBytecode.immutableReferences - Map from AST ids to bytecode ranges that reference immutables
         //   evm.methodIdentifiers - The list of function hashes
         //   evm.gasEstimates - Function gas estimates
-        //   ewasm.wast - Ewasm in WebAssembly S-expressions format
-        //   ewasm.wasm - Ewasm in WebAssembly binary format
         //
-        // Note that using a using `evm`, `evm.bytecode`, `ewasm`, etc. will select every
+        // Note that using a using `evm`, `evm.bytecode`, etc. will select every
         // target part of that output. Additionally, `*` can be used as a wildcard to request everything.
         //
         "outputSelection": {
@@ -501,7 +499,7 @@ Output Description
           // Mandatory: Error type, such as "TypeError", "InternalCompilerError", "Exception", etc.
           // See below for complete list of types.
           "type": "TypeError",
-          // Mandatory: Component where the error originated, such as "general", "ewasm", etc.
+          // Mandatory: Component where the error originated, such as "general" etc.
           "component": "general",
           // Mandatory ("error", "warning" or "info", but please note that this may be extended in the future)
           "severity": "error",
@@ -617,13 +615,6 @@ Output Description
                   "heavyLifting()": "infinite"
                 }
               }
-            },
-            // Ewasm related outputs
-            "ewasm": {
-              // S-expressions format
-              "wast": "",
-              // Binary format (hex string)
-              "wasm": ""
             }
           }
         }

docs/using-the-compiler.rst

@@ -1194,8 +1194,7 @@ An example Yul Object is shown below:
             // executing code is the constructor code)
             size := datasize("Contract1_deployed")
             offset := allocate(size)
-            // This will turn into a memory->memory copy for Ewasm and
-            // a codecopy for EVM
+            // This will turn into a codecopy for EVM
             datacopy(offset, dataoffset("Contract1_deployed"), size)
             return(offset, size)
         }

docs/yul.rst

@@ -315,7 +315,6 @@ void CompilerStack::reset(bool _keepSettings)
 		m_evmVersion = langutil::EVMVersion();
 		m_modelCheckerSettings = ModelCheckerSettings{};
 		m_generateIR = false;
-		m_generateEwasm = false;
 		m_revertStrings = RevertStrings::Default;
 		m_optimiserSettings = OptimiserSettings::minimal();
 		m_metadataLiteralSources = false;
@@ -681,7 +680,7 @@ bool CompilerStack::compile(State _stopAfter)
 				{
 					try
 					{
-						if (m_viaIR || m_generateIR || m_generateEwasm)
+						if (m_viaIR || m_generateIR)
 							generateIR(*contract);
 						if (m_generateEvmBytecode)
 						{
@@ -690,8 +689,6 @@ bool CompilerStack::compile(State _stopAfter)
 							else
 								compileContract(*contract, otherCompilers);
 						}
-						if (m_generateEwasm)
-							generateEwasm(*contract);
 					}
 					catch (Error const& _error)
 					{
@@ -892,22 +889,6 @@ string const& CompilerStack::yulIROptimized(string const& _contractName) const
 	return contract(_contractName).yulIROptimized;
 }
 
-string const& CompilerStack::ewasm(string const& _contractName) const
-{
-	if (m_stackState != CompilationSuccessful)
-		solThrow(CompilerError, "Compilation was not successful.");
-
-	return contract(_contractName).ewasm;
-}
-
-evmasm::LinkerObject const& CompilerStack::ewasmObject(string const& _contractName) const
-{
-	if (m_stackState != CompilationSuccessful)
-		solThrow(CompilerError, "Compilation was not successful.");
-
-	return contract(_contractName).ewasmObject;
-}
-
 evmasm::LinkerObject const& CompilerStack::object(string const& _contractName) const
 {
 	if (m_stackState != CompilationSuccessful)
@@ -1479,42 +1460,6 @@ void CompilerStack::generateEVMFromIR(ContractDefinition const& _contract)
 	assembleYul(_contract, compiledContract.evmAssembly, compiledContract.evmRuntimeAssembly);
 }
 
-void CompilerStack::generateEwasm(ContractDefinition const& _contract)
-{
-	solAssert(m_stackState >= AnalysisPerformed, "");
-	if (m_hasError)
-		solThrow(CompilerError, "Called generateEwasm with errors.");
-
-	if (!_contract.canBeDeployed())
-		return;
-
-	Contract& compiledContract = m_contracts.at(_contract.fullyQualifiedName());
-	solAssert(!compiledContract.yulIROptimized.empty(), "");
-	if (!compiledContract.ewasm.empty())
-		return;
-
-	// Re-parse the Yul IR in EVM dialect
-	yul::YulStack stack(
-		m_evmVersion,
-		m_eofVersion,
-		yul::YulStack::Language::StrictAssembly,
-		m_optimiserSettings,
-		m_debugInfoSelection
-	);
-	stack.parseAndAnalyze("", compiledContract.yulIROptimized);
-
-	stack.optimize();
-	stack.translate(yul::YulStack::Language::Ewasm);
-	stack.optimize();
-
-	//cout << yul::AsmPrinter{}(*stack.parserResult()->code) << endl;
-
-	// Turn into Ewasm text representation.
-	auto result = stack.assemble(yul::YulStack::Machine::Ewasm);
-	compiledContract.ewasm = std::move(result.assembly);
-	compiledContract.ewasmObject = std::move(*result.bytecode);
-}
-
 CompilerStack::Contract const& CompilerStack::contract(string const& _contractName) const
 {
 	solAssert(m_stackState >= AnalysisPerformed, "");

libsolidity/interface/CompilerStack.cpp

@@ -203,9 +203,6 @@ class CompilerStack: public langutil::CharStreamProvider
 	/// Enable generation of Yul IR code.
 	void enableIRGeneration(bool _enable = true) { m_generateIR = _enable; }
 
-	/// Enable experimental generation of Ewasm code. If enabled, IR is also generated.
-	void enableEwasmGeneration(bool _enable = true) { m_generateEwasm = _enable; }
-
 	/// @arg _metadataLiteralSources When true, store sources as literals in the contract metadata.
 	/// Must be set before parsing.
 	void useMetadataLiteralSources(bool _metadataLiteralSources);
@@ -282,12 +279,6 @@ class CompilerStack: public langutil::CharStreamProvider
 	/// @returns the optimized IR representation of a contract.
 	std::string const& yulIROptimized(std::string const& _contractName) const;
 
-	/// @returns the Ewasm text representation of a contract.
-	std::string const& ewasm(std::string const& _contractName) const;
-
-	/// @returns the Ewasm representation of a contract.
-	evmasm::LinkerObject const& ewasmObject(std::string const& _contractName) const;
-
 	/// @returns the assembled object for a contract.
 	evmasm::LinkerObject const& object(std::string const& _contractName) const;
 
@@ -389,8 +380,6 @@ class CompilerStack: public langutil::CharStreamProvider
 		evmasm::LinkerObject runtimeObject; ///< Runtime object.
 		std::string yulIR; ///< Yul IR code.
 		std::string yulIROptimized; ///< Optimized Yul IR code.
-		std::string ewasm; ///< Experimental Ewasm text representation
-		evmasm::LinkerObject ewasmObject; ///< Experimental Ewasm code
 		util::LazyInit<std::string const> metadata; ///< The metadata json that will be hashed into the chain.
 		util::LazyInit<Json::Value const> abi;
 		util::LazyInit<Json::Value const> storageLayout;
@@ -448,10 +437,6 @@ class CompilerStack: public langutil::CharStreamProvider
 	/// Depends on output generated by generateIR.
 	void generateEVMFromIR(ContractDefinition const& _contract);
 
-	/// Generate Ewasm representation for a single contract.
-	/// Depends on output generated by generateIR.
-	void generateEwasm(ContractDefinition const& _contract);
-
 	/// Links all the known library addresses in the available objects. Any unknown
 	/// library will still be kept as an unlinked placeholder in the objects.
 	void link();
@@ -510,7 +495,6 @@ class CompilerStack: public langutil::CharStreamProvider
 	std::map<std::string, std::set<std::string>> m_requestedContractNames;
 	bool m_generateEvmBytecode = true;
 	bool m_generateIR = false;
-	bool m_generateEwasm = false;
 	std::map<std::string, util::h160> m_libraries;
 	ImportRemapper m_importRemapper;
 	std::map<std::string const, Source> m_sources;

libsolidity/interface/CompilerStack.h

@@ -179,7 +179,7 @@ bool hashMatchesContent(string const& _hash, string const& _content)
 
 bool isArtifactRequested(Json::Value const& _outputSelection, string const& _artifact, bool _wildcardMatchesExperimental)
 {
-	static set<string> experimental{"ir", "irOptimized", "wast", "ewasm", "ewasm.wast"};
+	static set<string> experimental{"ir", "irOptimized"};
 	for (auto const& selectedArtifactJson: _outputSelection)
 	{
 		string const& selectedArtifact = selectedArtifactJson.asString();
@@ -190,7 +190,7 @@ bool isArtifactRequested(Json::Value const& _outputSelection, string const& _art
 			return true;
 		else if (selectedArtifact == "*")
 		{
-			// "ir", "irOptimized", "wast" and "ewasm.wast" can only be matched by "*" if activated.
+			// "ir", "irOptimized" can only be matched by "*" if activated.
 			if (experimental.count(_artifact) == 0 || _wildcardMatchesExperimental)
 				return true;
 		}
@@ -264,7 +264,6 @@ bool isBinaryRequested(Json::Value const& _outputSelection)
 	static vector<string> const outputsThatRequireBinaries = vector<string>{
 		"*",
 		"ir", "irOptimized",
-		"wast", "wasm", "ewasm.wast", "ewasm.wasm",
 		"evm.gasEstimates", "evm.legacyAssembly", "evm.assembly"
 	} + evmObjectComponents("bytecode") + evmObjectComponents("deployedBytecode");
 
@@ -295,29 +294,10 @@ bool isEvmBytecodeRequested(Json::Value const& _outputSelection)
 	return false;
 }
 
-/// @returns true if any Ewasm code was requested. Note that as an exception, '*' does not
-/// yet match "ewasm.wast" or "ewasm"
-bool isEwasmRequested(Json::Value const& _outputSelection)
-{
-	if (!_outputSelection.isObject())
-		return false;
-
-	for (auto const& fileRequests: _outputSelection)
-		for (auto const& requests: fileRequests)
-			for (auto const& request: requests)
-				if (request == "ewasm" || request == "ewasm.wast")
-					return true;
-
-	return false;
-}
-
 /// @returns true if any Yul IR was requested. Note that as an exception, '*' does not
 /// yet match "ir" or "irOptimized"
 bool isIRRequested(Json::Value const& _outputSelection)
 {
-	if (isEwasmRequested(_outputSelection))
-		return true;
-
 	if (!_outputSelection.isObject())
 		return false;
 
@@ -1175,7 +1155,6 @@ Json::Value StandardCompiler::compileSolidity(StandardCompiler::InputsAndSetting
 
 	compilerStack.enableEvmBytecodeGeneration(isEvmBytecodeRequested(_inputsAndSettings.outputSelection));
 	compilerStack.enableIRGeneration(isIRRequested(_inputsAndSettings.outputSelection));
-	compilerStack.enableEwasmGeneration(isEwasmRequested(_inputsAndSettings.outputSelection));
 
 	Json::Value errors = std::move(_inputsAndSettings.errors);
 
@@ -1374,12 +1353,6 @@ Json::Value StandardCompiler::compileSolidity(StandardCompiler::InputsAndSetting
 		if (compilationSuccess && isArtifactRequested(_inputsAndSettings.outputSelection, file, name, "irOptimized", wildcardMatchesExperimental))
 			contractData["irOptimized"] = compilerStack.yulIROptimized(contractName);
 
-		// Ewasm
-		if (compilationSuccess && isArtifactRequested(_inputsAndSettings.outputSelection, file, name, "ewasm.wast", wildcardMatchesExperimental))
-			contractData["ewasm"]["wast"] = compilerStack.ewasm(contractName);
-		if (compilationSuccess && isArtifactRequested(_inputsAndSettings.outputSelection, file, name, "ewasm.wasm", wildcardMatchesExperimental))
-			contractData["ewasm"]["wasm"] = compilerStack.ewasmObject(contractName).toHex();
-
 		// EVM
 		Json::Value evmData(Json::objectValue);
 		if (compilationSuccess && isArtifactRequested(_inputsAndSettings.outputSelection, file, name, "evm.assembly", wildcardMatchesExperimental))

libsolidity/interface/StandardCompiler.cpp

@@ -1,19 +1,3 @@
-# This will re-generate the polyfill headers, if any file within libyul/backends/wasm/polyfill/ was modified.
-set_directory_properties(PROPERTY CMAKE_CONFIGURE_DEPENDS ${CMAKE_SOURCE_DIR}/libyul/backends/wasm/polyfill/)
-
-set(POLYFILLS Arithmetic Bitwise Comparison Conversion Interface Keccak Logical Memory)
-set(GENERATED_POLYFILL_HEADERS)
-foreach(polyfill IN LISTS POLYFILLS)
-	set(POLYFILL_FILE ${CMAKE_SOURCE_DIR}/libyul/backends/wasm/polyfill/${polyfill}.yul)
-	file(READ ${POLYFILL_FILE} EWASM_POLYFILL_CONTENT HEX)
-	string(REGEX MATCHALL ".." EWASM_POLYFILL_CONTENT "${EWASM_POLYFILL_CONTENT}")
-	string(REGEX REPLACE ";" ",\n\t0x" EWASM_POLYFILL_CONTENT "${EWASM_POLYFILL_CONTENT}")
-	set(EWASM_POLYFILL_CONTENT "0x${EWASM_POLYFILL_CONTENT}")
-	set(EWASM_POLYFILL_NAME ${polyfill})
-	configure_file("${CMAKE_SOURCE_DIR}/cmake/templates/ewasm_polyfill.in" ${CMAKE_BINARY_DIR}/include/ewasmPolyfills/${polyfill}.h @ONLY)
-	list(APPEND GENERATED_POLYFILL_HEADERS ${CMAKE_BINARY_DIR}/include/ewasmPolyfills/${polyfill}.h)
-endforeach()
-
 add_library(yul
 	${GENERATED_POLYFILL_HEADERS}
 
@@ -80,20 +64,6 @@ add_library(yul
 	backends/evm/StackLayoutGenerator.h
 	backends/evm/VariableReferenceCounter.h
 	backends/evm/VariableReferenceCounter.cpp
-	backends/wasm/EVMToEwasmTranslator.cpp
-	backends/wasm/EVMToEwasmTranslator.h
-	backends/wasm/BinaryTransform.cpp
-	backends/wasm/BinaryTransform.h
-	backends/wasm/TextTransform.cpp
-	backends/wasm/TextTransform.h
-	backends/wasm/WasmCodeTransform.cpp
-	backends/wasm/WasmCodeTransform.h
-	backends/wasm/WasmDialect.cpp
-	backends/wasm/WasmDialect.h
-	backends/wasm/WasmObjectCompiler.cpp
-	backends/wasm/WasmObjectCompiler.h
-	backends/wasm/WordSizeTransform.cpp
-	backends/wasm/WordSizeTransform.h
 	optimiser/ASTCopier.cpp
 	optimiser/ASTCopier.h
 	optimiser/ASTWalker.cpp