Convert the wast test harness into a crate.

This uses a build.rs file to collect all the wast tests and create
individual `#[test]` lines for them, so that `cargo test` can run them
in parallel.

Cargo.toml

@@ -25,6 +25,7 @@ cranelift-wasm = { git = "https://github.com/sunfishcode/cranelift.git", branch
 wasmtime-environ = { path = "lib/environ" }
 wasmtime-execute = { path = "lib/execute" }
 wasmtime-obj = { path = "lib/obj" }
+wasmtime-wast = { path = "lib/wast" }
 docopt = "1.0.1"
 serde = "1.0.75"
 serde_derive = "1.0.75"

lib/execute/src/lib.rs

@@ -55,6 +55,7 @@ mod signalhandlers;
 mod table;
 mod traphandlers;
 mod vmcontext;
+mod world;
 
 pub use code::Code;
 pub use execute::{compile_and_link_module, finish_instantiation};
@@ -62,6 +63,7 @@ pub use instance::Instance;
 pub use invoke::{invoke, InvokeOutcome, Value};
 pub use traphandlers::{call_wasm, LookupCodeSegment, RecordTrap, Unwind};
 pub use vmcontext::VMContext;
+pub use world::InstanceWorld;
 
 #[cfg(not(feature = "std"))]
 mod std {

lib/execute/src/world.rs

@@ -0,0 +1,66 @@
+use cranelift_codegen::isa;
+use std::str;
+use wasmtime_environ::{Compilation, Module, ModuleEnvironment, Tunables};
+use {compile_and_link_module, finish_instantiation, invoke, Code, Instance, InvokeOutcome, Value};
+
+/// A module, an instance of that module, and accompanying compilation artifacts.
+///
+/// TODO: Rename and reorganize this.
+pub struct InstanceWorld {
+    module: Module,
+    instance: Instance,
+    compilation: Compilation,
+}
+
+impl InstanceWorld {
+    /// Create a new `InstanceWorld` by compiling the wasm module in `data` and instatiating it.
+    pub fn new(code: &mut Code, isa: &isa::TargetIsa, data: &[u8]) -> Result<Self, String> {
+        let mut module = Module::new();
+        let tunables = Tunables::default();
+        let (instance, compilation) = {
+            let translation = {
+                let environ = ModuleEnvironment::new(isa, &mut module, tunables);
+
+                environ.translate(&data).map_err(|e| e.to_string())?
+            };
+
+            let imports_resolver = |_env: &str, _function: &str| None;
+
+            let compilation = compile_and_link_module(isa, &translation, &imports_resolver)?;
+            let mut instance = Instance::new(
+                translation.module,
+                &compilation,
+                &translation.lazy.data_initializers,
+            )?;
+
+            finish_instantiation(code, isa, &translation.module, &compilation, &mut instance)?;
+
+            (instance, compilation)
+        };
+
+        Ok(Self {
+            module,
+            instance,
+            compilation,
+        })
+    }
+
+    /// Invoke a function in this `InstanceWorld` by name.
+    pub fn invoke(
+        &mut self,
+        code: &mut Code,
+        isa: &isa::TargetIsa,
+        function_name: &str,
+        args: &[Value],
+    ) -> Result<InvokeOutcome, String> {
+        invoke(
+            code,
+            isa,
+            &self.module,
+            &self.compilation,
+            self.instance.vmctx(),
+            &function_name,
+            args,
+        ).map_err(|e| e.to_string())
+    }
+}

lib/wast/Cargo.toml

@@ -0,0 +1,20 @@
+[package]
+name = "wasmtime-wast"
+version = "0.0.0"
+authors = ["The Cranelift Project Developers"]
+publish = false
+description = "wast testing support for wasmtime"
+categories = ["wasm"]
+repository = "https://github.com/CraneStation/wasmtime"
+license = "Apache-2.0 WITH LLVM-exception"
+readme = "README.md"
+
+[dependencies]
+cranelift-codegen = { git = "https://github.com/sunfishcode/cranelift.git", branch = "guard-offset" }
+cranelift-native = { git = "https://github.com/sunfishcode/cranelift.git", branch = "guard-offset" }
+wasmtime-execute = { path = "../execute" }
+wabt = "0.7"
+
+[badges]
+maintenance = { status = "experimental" }
+travis-ci = { repository = "CraneStation/wasmtime" }

lib/wast/LICENSE

@@ -0,0 +1,220 @@
+
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+

lib/wast/README.md

@@ -0,0 +1,4 @@
+This is the `wasmtime-wast` crate, which contains support for running
+"wast" tests, such as the spec testsuite.
+
+[`wasmtime-wast`]: https://crates.io/crates/wasmtime-wast

lib/wast/build.rs

@@ -0,0 +1,46 @@
+use std::env;
+use std::fs::{read_dir, File};
+use std::io::Write;
+use std::path::PathBuf;
+
+fn main() {
+    let out_dir =
+        PathBuf::from(env::var("OUT_DIR").expect("The OUT_DIR environment variable must be set"));
+    let mut out =
+        File::create(out_dir.join("run_wast_files.rs")).expect("error creating run_wast_files.rs");
+
+    let mut paths: Vec<_> = read_dir("spec_testsuite")
+        .unwrap()
+        .map(|r| r.unwrap())
+        .filter(|p| {
+            // Ignore files starting with `.`, which could be editor temporary files
+            if let Some(stem) = p.path().file_stem() {
+                if let Some(stemstr) = stem.to_str() {
+                    return !stemstr.starts_with('.');
+                }
+            }
+            false
+        }).collect();
+
+    paths.sort_by_key(|dir| dir.path());
+    for path in paths {
+        let path = path.path();
+        writeln!(out, "#[test]");
+        writeln!(
+            out,
+            "fn {}() {{",
+            path.file_stem()
+                .expect("file_stem")
+                .to_str()
+                .expect("to_str")
+        );
+        writeln!(
+            out,
+            "    wast_file(Path::new(\"{}\"), &*native_isa()).expect(\"error loading wast file {}\");",
+            path.display(),
+            path.display()
+        );
+        writeln!(out, "}}");
+        writeln!(out);
+    }
+}

lib/wast/src/lib.rs

@@ -0,0 +1,34 @@
+//! JIT-style runtime for WebAssembly using Cranelift.
+
+#![deny(missing_docs, trivial_numeric_casts, unused_extern_crates)]
+#![warn(unused_import_braces)]
+#![deny(unstable_features)]
+#![cfg_attr(
+    feature = "clippy",
+    plugin(clippy(conf_file = "../../clippy.toml"))
+)]
+#![cfg_attr(
+    feature = "cargo-clippy",
+    allow(new_without_default, new_without_default_derive)
+)]
+#![cfg_attr(
+    feature = "cargo-clippy",
+    warn(
+        float_arithmetic,
+        mut_mut,
+        nonminimal_bool,
+        option_map_unwrap_or,
+        option_map_unwrap_or_else,
+        print_stdout,
+        unicode_not_nfc,
+        use_self
+    )
+)]
+
+extern crate cranelift_codegen;
+extern crate wabt;
+extern crate wasmtime_execute;
+
+mod wast;
+
+pub use wast::{wast_buffer, wast_file};

lib/wast/src/wast.rs

@@ -0,0 +1,177 @@
+use cranelift_codegen::isa;
+use std::collections::HashMap;
+use std::fs;
+use std::io;
+use std::io::Read;
+use std::path::Path;
+use std::str;
+use wabt::script::{self, Action, Command, CommandKind, ModuleBinary, ScriptParser};
+use wasmtime_execute::{Code, InstanceWorld, InvokeOutcome, Value};
+
+struct Instances {
+    current: Option<InstanceWorld>,
+    namespace: HashMap<String, InstanceWorld>,
+    code: Code,
+}
+
+impl Instances {
+    pub fn new() -> Self {
+        Self {
+            current: None,
+            namespace: HashMap::new(),
+            code: Code::new(),
+        }
+    }
+
+    fn instantiate(&mut self, isa: &isa::TargetIsa, module: ModuleBinary) -> InstanceWorld {
+        InstanceWorld::new(&mut self.code, isa, &module.into_vec()).unwrap()
+    }
+
+    pub fn define_unnamed_module(&mut self, isa: &isa::TargetIsa, module: ModuleBinary) {
+        self.current = Some(self.instantiate(isa, module));
+    }
+
+    pub fn define_named_module(
+        &mut self,
+        isa: &isa::TargetIsa,
+        name: String,
+        module: ModuleBinary,
+    ) {
+        let world = self.instantiate(isa, module);
+        self.namespace.insert(name, world);
+    }
+
+    pub fn perform_action(&mut self, isa: &isa::TargetIsa, action: Action) -> InvokeOutcome {
+        match action {
+            Action::Invoke {
+                module,
+                field,
+                args,
+            } => {
+                let mut value_args = Vec::with_capacity(args.len());
+                for a in args {
+                    value_args.push(match a {
+                        script::Value::I32(i) => Value::I32(i),
+                        script::Value::I64(i) => Value::I64(i),
+                        script::Value::F32(i) => Value::F32(i.to_bits()),
+                        script::Value::F64(i) => Value::F64(i.to_bits()),
+                    });
+                }
+                match module {
+                    None => match self.current {
+                        None => panic!("invoke performed with no module present"),
+                        Some(ref mut instance_world) => instance_world
+                            .invoke(&mut self.code, isa, &field, &value_args)
+                            .expect(&format!("error invoking {} in current module", field)),
+                    },
+                    Some(name) => self
+                        .namespace
+                        .get_mut(&name)
+                        .expect(&format!("module {} not declared", name))
+                        .invoke(&mut self.code, isa, &field, &value_args)
+                        .expect(&format!("error invoking {} in module {}", field, name)),
+                }
+            }
+            _ => panic!("unsupported action {:?}", action),
+        }
+    }
+}
+
+/// Run a wast script from a byte buffer.
+pub fn wast_buffer(name: &str, isa: &isa::TargetIsa, wast: &[u8]) {
+    let mut parser = ScriptParser::from_str(str::from_utf8(wast).unwrap()).unwrap();
+    let mut instances = Instances::new();
+
+    while let Some(Command { kind, line }) = parser.next().unwrap() {
+        match kind {
+            CommandKind::Module { module, name } => {
+                if let Some(name) = name {
+                    instances.define_named_module(&*isa, name, module.clone());
+                }
+
+                instances.define_unnamed_module(&*isa, module)
+            }
+            CommandKind::PerformAction(action) => match instances.perform_action(&*isa, action) {
+                InvokeOutcome::Returned { .. } => {}
+                InvokeOutcome::Trapped { message } => {
+                    panic!("{}:{}: a trap occurred: {}", name, line, message);
+                }
+            },
+            CommandKind::AssertReturn { action, expected } => {
+                match instances.perform_action(&*isa, action) {
+                    InvokeOutcome::Returned { values } => {
+                        for (v, e) in values.iter().zip(expected.iter()) {
+                            match *e {
+                                script::Value::I32(x) => {
+                                    assert_eq!(x, v.unwrap_i32(), "at {}:{}", name, line)
+                                }
+                                script::Value::I64(x) => {
+                                    assert_eq!(x, v.unwrap_i64(), "at {}:{}", name, line)
+                                }
+                                script::Value::F32(x) => {
+                                    assert_eq!(x.to_bits(), v.unwrap_f32(), "at {}:{}", name, line)
+                                }
+                                script::Value::F64(x) => {
+                                    assert_eq!(x.to_bits(), v.unwrap_f64(), "at {}:{}", name, line)
+                                }
+                            };
+                        }
+                    }
+                    InvokeOutcome::Trapped { message } => {
+                        panic!(
+                            "{}:{}: expected normal return, but a trap occurred: {}",
+                            name, line, message
+                        );
+                    }
+                }
+            }
+            CommandKind::AssertTrap { action, message } => {
+                match instances.perform_action(&*isa, action) {
+                    InvokeOutcome::Returned { values } => panic!(
+                        "{}:{}: expected trap, but invoke returned with {:?}",
+                        name, line, values
+                    ),
+                    InvokeOutcome::Trapped {
+                        message: trap_message,
+                    } => {
+                        println!(
+                            "{}:{}: TODO: Check the trap message: expected {}, got {}",
+                            name, line, message, trap_message
+                        );
+                    }
+                }
+            }
+            CommandKind::AssertExhaustion { action } => {
+                match instances.perform_action(&*isa, action) {
+                    InvokeOutcome::Returned { values } => panic!(
+                        "{}:{}: expected exhaustion, but invoke returned with {:?}",
+                        name, line, values
+                    ),
+                    InvokeOutcome::Trapped { message } => {
+                        println!(
+                            "{}:{}: TODO: Check the exhaustion message: {}",
+                            name, line, message
+                        );
+                    }
+                }
+            }
+            command => {
+                println!("{}:{}: TODO: implement {:?}", name, line, command);
+            }
+        }
+    }
+}
+
+/// Run a wast script from a file.
+pub fn wast_file(path: &Path, isa: &isa::TargetIsa) -> Result<(), String> {
+    let wast = read_to_end(path).map_err(|e| e.to_string())?;
+    wast_buffer(&path.display().to_string(), isa, &wast);
+    Ok(())
+}
+
+fn read_to_end(path: &Path) -> Result<Vec<u8>, io::Error> {
+    let mut buf: Vec<u8> = Vec::new();
+    let mut file = fs::File::open(path)?;
+    file.read_to_end(&mut buf)?;
+    Ok(buf)
+}

lib/wast/tests/wast_files.rs

@@ -0,0 +1,22 @@
+extern crate cranelift_codegen;
+extern crate cranelift_native;
+extern crate wasmtime_wast;
+
+use cranelift_codegen::isa;
+use cranelift_codegen::settings;
+use cranelift_codegen::settings::Configurable;
+use std::path::Path;
+use wasmtime_wast::wast_file;
+
+include!(concat!(env!("OUT_DIR"), "/run_wast_files.rs"));
+
+#[cfg(test)]
+fn native_isa() -> Box<isa::TargetIsa> {
+    let mut flag_builder = settings::builder();
+    flag_builder.enable("enable_verifier").unwrap();
+
+    let isa_builder = cranelift_native::builder().unwrap_or_else(|_| {
+        panic!("host machine is not a supported target");
+    });
+    isa_builder.finish(settings::Flags::new(flag_builder))
+}

tests/wast.rs

@@ -1,291 +0,0 @@
-extern crate cranelift_codegen;
-extern crate wabt;
-extern crate wasmtime_environ;
-extern crate wasmtime_execute;
-
-use cranelift_codegen::settings::Configurable;
-use cranelift_codegen::{isa, settings};
-use std::collections::HashMap;
-use std::fs;
-use std::io;
-use std::io::Read;
-use std::path::Path;
-use std::str;
-use wabt::script::{self, Action, Command, CommandKind, ScriptParser};
-use wasmtime_environ::{Compilation, Module, ModuleEnvironment, Tunables};
-use wasmtime_execute::{
-    compile_and_link_module, finish_instantiation, invoke, Code, Instance, InvokeOutcome, Value,
-};
-
-struct InstanceWorld {
-    module: Module,
-    instance: Instance,
-    compilation: Compilation,
-}
-
-impl InstanceWorld {
-    fn new(code: &mut Code, isa: &isa::TargetIsa, data: &[u8]) -> Result<Self, String> {
-        let mut module = Module::new();
-        let tunables = Tunables::default();
-        let (instance, compilation) = {
-            let translation = {
-                let environ = ModuleEnvironment::new(isa, &mut module, tunables);
-
-                environ.translate(&data).map_err(|e| e.to_string())?
-            };
-
-            let imports_resolver = |_env: &str, _function: &str| None;
-
-            let compilation = compile_and_link_module(isa, &translation, &imports_resolver)?;
-            let mut instance = Instance::new(
-                translation.module,
-                &compilation,
-                &translation.lazy.data_initializers,
-            )?;
-
-            finish_instantiation(code, isa, &translation.module, &compilation, &mut instance)?;
-
-            (instance, compilation)
-        };
-
-        Ok(Self {
-            module,
-            instance,
-            compilation,
-        })
-    }
-
-    fn invoke(
-        &mut self,
-        code: &mut Code,
-        isa: &isa::TargetIsa,
-        f: &str,
-        args: &[Value],
-    ) -> Result<InvokeOutcome, String> {
-        invoke(
-            code,
-            isa,
-            &self.module,
-            &self.compilation,
-            self.instance.vmctx(),
-            &f,
-            args,
-        ).map_err(|e| e.to_string())
-    }
-}
-
-fn translate(code: &mut Code, isa: &isa::TargetIsa, data: &[u8]) -> Result<InstanceWorld, String> {
-    InstanceWorld::new(code, isa, data)
-}
-
-struct Instances {
-    current: Option<InstanceWorld>,
-    namespace: HashMap<String, InstanceWorld>,
-}
-
-impl Instances {
-    fn new() -> Self {
-        Self {
-            current: None,
-            namespace: HashMap::new(),
-        }
-    }
-
-    fn unnamed(&mut self, instance: InstanceWorld) {
-        self.current = Some(instance);
-    }
-
-    fn named(&mut self, name: String, instance: InstanceWorld) {
-        self.namespace.insert(name, instance);
-    }
-
-    fn perform_action(
-        &mut self,
-        code: &mut Code,
-        isa: &isa::TargetIsa,
-        action: Action,
-    ) -> InvokeOutcome {
-        match action {
-            Action::Invoke {
-                module,
-                field,
-                args,
-            } => {
-                let mut value_args = Vec::new();
-                for a in args {
-                    value_args.push(match a {
-                        script::Value::I32(i) => Value::I32(i),
-                        script::Value::I64(i) => Value::I64(i),
-                        script::Value::F32(i) => Value::F32(i.to_bits()),
-                        script::Value::F64(i) => Value::F64(i.to_bits()),
-                    });
-                }
-                match module {
-                    None => match self.current {
-                        None => panic!("invoke performed with no module present"),
-                        Some(ref mut instance_world) => instance_world
-                            .invoke(code, isa, &field, &value_args)
-                            .expect(&format!("error invoking {} in current module", field)),
-                    },
-                    Some(name) => self
-                        .namespace
-                        .get_mut(&name)
-                        .expect(&format!("module {} not declared", name))
-                        .invoke(code, isa, &field, &value_args)
-                        .expect(&format!("error invoking {} in module {}", field, name)),
-                }
-            }
-            _ => panic!("unsupported action {:?}", action),
-        }
-    }
-}
-
-#[test]
-fn spec_core() {
-    let mut flag_builder = settings::builder();
-    flag_builder.enable("enable_verifier").unwrap();
-
-    let isa_builder = cranelift_native::builder().unwrap_or_else(|_| {
-        panic!("host machine is not a supported target");
-    });
-    let isa = isa_builder.finish(settings::Flags::new(flag_builder));
-
-    let mut paths: Vec<_> = fs::read_dir("tests/wast")
-        .unwrap()
-        .map(|r| r.unwrap())
-        .filter(|p| {
-            // Ignore files starting with `.`, which could be editor temporary files
-            if let Some(stem) = p.path().file_stem() {
-                if let Some(stemstr) = stem.to_str() {
-                    return !stemstr.starts_with('.');
-                }
-            }
-            false
-        }).collect();
-    paths.sort_by_key(|dir| dir.path());
-    for path in paths {
-        let path = path.path();
-        let source = read_to_end(&path).unwrap();
-        test_wast(&path, &*isa, &source);
-    }
-}
-
-#[cfg(test)]
-fn read_to_end(path: &Path) -> Result<Vec<u8>, io::Error> {
-    let mut buf: Vec<u8> = Vec::new();
-    let mut file = fs::File::open(path)?;
-    file.read_to_end(&mut buf)?;
-    Ok(buf)
-}
-
-#[cfg(test)]
-fn test_wast(path: &Path, isa: &isa::TargetIsa, wast: &[u8]) {
-    println!("Testing {}", path.display());
-
-    let mut parser = ScriptParser::from_str(str::from_utf8(wast).unwrap()).unwrap();
-    let mut instances = Instances::new();
-    let mut code = Code::new();
-
-    while let Some(Command { kind, line }) = parser.next().unwrap() {
-        match kind {
-            CommandKind::Module { module, name } => {
-                if let Some(name) = name {
-                    instances.named(
-                        name,
-                        translate(&mut code, &*isa, &module.clone().into_vec()).unwrap(),
-                    );
-                }
-
-                instances.unnamed(translate(&mut code, &*isa, &module.clone().into_vec()).unwrap());
-            }
-            CommandKind::PerformAction(action) => {
-                match instances.perform_action(&mut code, &*isa, action) {
-                    InvokeOutcome::Returned { .. } => {}
-                    InvokeOutcome::Trapped { message } => {
-                        panic!("{}:{}: a trap occurred: {}", path.display(), line, message);
-                    }
-                }
-            }
-            CommandKind::AssertReturn { action, expected } => {
-                match instances.perform_action(&mut code, &*isa, action) {
-                    InvokeOutcome::Returned { values } => {
-                        for (v, e) in values.iter().zip(expected.iter()) {
-                            match *e {
-                                script::Value::I32(x) => {
-                                    assert_eq!(x, v.unwrap_i32(), "at {}:{}", path.display(), line)
-                                }
-                                script::Value::I64(x) => {
-                                    assert_eq!(x, v.unwrap_i64(), "at {}:{}", path.display(), line)
-                                }
-                                script::Value::F32(x) => assert_eq!(
-                                    x.to_bits(),
-                                    v.unwrap_f32(),
-                                    "at {}:{}",
-                                    path.display(),
-                                    line
-                                ),
-                                script::Value::F64(x) => assert_eq!(
-                                    x.to_bits(),
-                                    v.unwrap_f64(),
-                                    "at {}:{}",
-                                    path.display(),
-                                    line
-                                ),
-                            };
-                        }
-                    }
-                    InvokeOutcome::Trapped { message } => {
-                        panic!(
-                            "{}:{}: expected normal return, but a trap occurred: {}",
-                            path.display(),
-                            line,
-                            message
-                        );
-                    }
-                }
-            }
-            CommandKind::AssertTrap { action, message } => {
-                match instances.perform_action(&mut code, &*isa, action) {
-                    InvokeOutcome::Returned { values } => panic!(
-                        "{}:{}: expected trap, but invoke returned with {:?}",
-                        path.display(),
-                        line,
-                        values
-                    ),
-                    InvokeOutcome::Trapped {
-                        message: trap_message,
-                    } => {
-                        println!(
-                            "{}:{}: TODO: Check the trap message: expected {}, got {}",
-                            path.display(),
-                            line,
-                            message,
-                            trap_message
-                        );
-                    }
-                }
-            }
-            CommandKind::AssertExhaustion { action } => {
-                match instances.perform_action(&mut code, &*isa, action) {
-                    InvokeOutcome::Returned { values } => panic!(
-                        "{}:{}: expected exhaustion, but invoke returned with {:?}",
-                        path.display(),
-                        line,
-                        values
-                    ),
-                    InvokeOutcome::Trapped { message } => {
-                        println!(
-                            "{}:{}: TODO: Check the exhaustion message: {}",
-                            path.display(),
-                            line,
-                            message
-                        );
-                    }
-                }
-            }
-            command => {
-                println!("{}:{}: TODO: implement {:?}", path.display(), line, command);
-            }
-        }
-    }
-}