Integrate Wasmtime for runtime execution (#3869)

* executor: Use non wasmi-specific execution in tests.

* executor: Move all runtime execution tests into tests file.

* executor: Use test_case macro to easily execute tests with different
Wasm execution methods.

* executor: Convert errors to strings with Display, not Debug.

* node-executor: Rewrite benchmarks with criterion.

They were not passing compilation before and criterion seems to be more
widely used in Substrate.

* executor: Begin implementation of Wasm runtime.

The implementation demonstrates the outline of the execution, but does
not link against the external host functions.

* executor: Define and implement basic FunctionExecutor.

The SandboxCapabilities::invoke is still left unimplemented.

* executor: Implement host function trampoline generation.

* executor: Instantiate and link runtime module to env module.

* executor: Provide input data during wasmtime execution.

* executor: Implement SandboxCapabilites::invoke for wasmtime executor.

* executor: Integrate and test wasmtime execution method.

* executor: Improve FunctionExecution error messages.

* Scope the unsafe blocks to be smaller.

* Rename TrampolineState to EnvState.

* Let EnvState own its own compiler instead of unsafe lifetime cast.

* Refactor out some common wasmi/wasmtime logic.

* Typos and cosmetic changes.

* More trampoline comments.

* Cargo.lock update.

* cli: CLI option for running Substrate with compiled Wasm execution.

* executor: Switch dependency from fork to official wasmtime repo.

* Quiet down cranelift logs.

* Explicitly catch panics during host calls.

We do this to ensure that panics do not cross language boundaries.

* Additional checks and clarifications in make_trampoline.

* Fixes after merge from master and panic safety for wasmtime
instantiation.

Cargo.toml

@@ -108,3 +108,4 @@ members = [
 [profile.release]
 # Substrate runtime requires unwinding.
 panic = "unwind"
+

core/cli/Cargo.toml

@@ -38,3 +38,8 @@ rpassword = "4.0.1"
 
 [dev-dependencies]
 tempdir = "0.3.7"
+
+[features]
+wasmtime = [
+    "service/wasmtime",
+]

core/cli/src/lib.rs

@@ -897,6 +897,7 @@ fn init_logger(pattern: &str) {
 	// Disable info logging by default for some modules:
 	builder.filter(Some("ws"), log::LevelFilter::Off);
 	builder.filter(Some("hyper"), log::LevelFilter::Warn);
+	builder.filter(Some("cranelift_wasm"), log::LevelFilter::Warn);
 	// Enable info for others.
 	builder.filter(None, log::LevelFilter::Info);
 

core/cli/src/params.rs

@@ -50,13 +50,32 @@ arg_enum! {
 	pub enum WasmExecutionMethod {
 		// Uses an interpreter.
 		Interpreted,
+		// Uses a compiled runtime.
+		Compiled,
+	}
+}
+
+impl WasmExecutionMethod {
+	/// Returns list of variants that are not disabled by feature flags.
+	fn enabled_variants() -> Vec<&'static str> {
+		Self::variants()
+			.iter()
+			.cloned()
+			.filter(|&name| cfg!(feature = "wasmtime") || name != "Compiled")
+			.collect()
 	}
 }
 
 impl Into<service::config::WasmExecutionMethod> for WasmExecutionMethod {
 	fn into(self) -> service::config::WasmExecutionMethod {
 		match self {
 			WasmExecutionMethod::Interpreted => service::config::WasmExecutionMethod::Interpreted,
+			#[cfg(feature = "wasmtime")]
+			WasmExecutionMethod::Compiled => service::config::WasmExecutionMethod::Compiled,
+			#[cfg(not(feature = "wasmtime"))]
+			WasmExecutionMethod::Compiled => panic!(
+				"Substrate must be compiled with \"wasmtime\" feature for compiled Wasm execution"
+			),
 		}
 	}
 }
@@ -429,7 +448,7 @@ pub struct RunCmd {
 	#[structopt(
 		long = "wasm-execution",
 		value_name = "METHOD",
-		possible_values = &WasmExecutionMethod::variants(),
+		possible_values = &WasmExecutionMethod::enabled_variants(),
 		case_insensitive = true,
 		default_value = "Interpreted"
 	)]

core/executor/Cargo.toml

@@ -23,6 +23,15 @@ log = "0.4.8"
 libsecp256k1 = "0.3.0"
 tiny-keccak = "1.5.0"
 
+cranelift-codegen = { version = "0.46.1", optional = true }
+cranelift-entity = { version = "0.46.1", optional = true }
+cranelift-frontend = { version = "0.46.1", optional = true }
+cranelift-native = { version = "0.46.1", optional = true }
+cranelift-wasm = { version = "0.46.1", optional = true }
+wasmtime-environ = { version = "0.2", optional = true, git = "https://github.com/CraneStation/wasmtime.git", rev = "71dd73d6" }
+wasmtime-jit = { version = "0.2", optional = true, git = "https://github.com/CraneStation/wasmtime.git", rev = "71dd73d6" }
+wasmtime-runtime = { version = "0.2", optional = true, git = "https://github.com/CraneStation/wasmtime.git", rev = "71dd73d6" }
+
 [dev-dependencies]
 assert_matches = "1.3.0"
 wabt = "0.9.2"
@@ -31,7 +40,18 @@ runtime-test = { package = "substrate-runtime-test", path = "runtime-test" }
 substrate-client = { path = "../client" }
 substrate-offchain = { path = "../offchain/" }
 state_machine = { package = "substrate-state-machine", path = "../state-machine"  }
+test-case = "0.3.3"
 
 [features]
 default = []
 wasm-extern-trace = []
+wasmtime = [
+    "cranelift-codegen",
+    "cranelift-entity",
+    "cranelift-frontend",
+    "cranelift-native",
+    "cranelift-wasm",
+    "wasmtime-environ",
+    "wasmtime-jit",
+    "wasmtime-runtime",
+]

core/executor/src/error.rs

@@ -18,6 +18,8 @@
 
 use serializer;
 use wasmi;
+#[cfg(feature = "wasmtime")]
+use wasmtime_jit::{ActionError, SetupError};
 
 /// Result type alias.
 pub type Result<T> = std::result::Result<T, Error>;
@@ -31,6 +33,9 @@ pub enum Error {
 	Trap(wasmi::Trap),
 	/// Wasmi loading/instantiating error
 	Wasmi(wasmi::Error),
+	/// Wasmtime action error
+	#[cfg(feature = "wasmtime")]
+	Wasmtime(ActionError),
 	/// Error in the API. Parameter is an error message.
 	ApiError(String),
 	/// Method is not found
@@ -75,9 +80,9 @@ pub enum Error {
 	/// Someone tried to allocate more memory than the allowed maximum per allocation.
 	#[display(fmt="Requested allocation size is too large")]
 	RequestedAllocationTooLarge,
-	/// Executing the given function failed with the given error.
-	#[display(fmt="Function execution failed with: {}", _0)]
-	FunctionExecution(String),
+	/// Execution of a host function failed.
+	#[display(fmt="Host function {} execution failed with: {}", _0, _1)]
+	FunctionExecution(String, String),
 }
 
 impl std::error::Error for Error {
@@ -116,6 +121,16 @@ pub enum WasmError {
 	InvalidModule,
 	/// Wasm code could not be deserialized.
 	CantDeserializeWasm,
+	/// The module does not export a linear memory named `memory`.
+	InvalidMemory,
+	/// The number of heap pages requested is disallowed by the module.
+	InvalidHeapPages,
 	/// Instantiation error.
-	Instantiation(Error),
+	Instantiation(String),
+	/// The compiler does not support the host machine as a target.
+	#[cfg(feature = "wasmtime")]
+	MissingCompilerSupport(&'static str),
+	/// Wasmtime setup error.
+	#[cfg(feature = "wasmtime")]
+	WasmtimeSetup(SetupError),
 }