Add options to wasmtime and wasm2obj to pick compilation strategy.

src/bin/wasm2obj.rs

@@ -63,7 +63,7 @@ The translation is dependent on the environment chosen.
 The default is a dummy environment that produces placeholder values.
 
 Usage:
-    wasm2obj [--target TARGET] [-Odg] [--disable-cache | --cache-config=<cache_config_file>] [--enable-simd] <file> -o <output>
+    wasm2obj [--target TARGET] [-Odg] [--disable-cache | --cache-config=<cache_config_file>] [--enable-simd] [--always-lightbeam | --always-cranelift] <file> -o <output>
     wasm2obj --create-cache-config [--cache-config=<cache_config_file>]
     wasm2obj --help | --version
 
@@ -80,6 +80,8 @@ Options:
                         creates default configuration and writes it to the disk,
                         use with --cache-config to specify custom config file
                         instead of default one
+    --always-lightbeam  use Lightbeam for all compilation
+    --always-cranelift  use Cranelift for all compilation
     --enable-simd       enable proposed SIMD instructions
     -O, --optimize      runs optimization passes on the translated functions
     --version           print the Cranelift version
@@ -97,6 +99,8 @@ struct Args {
     flag_cache_config: Option<String>,
     flag_create_cache_config: bool,
     flag_enable_simd: bool,
+    flag_always_lightbeam: bool,
+    flag_always_cranelift: bool,
     flag_optimize: bool,
 }
 

src/bin/wasmtime.rs

@@ -44,6 +44,7 @@ use std::path::{Path, PathBuf};
 use std::process::exit;
 use wabt;
 use wasi_common::preopen_dir;
+use wasmtime::pick_compilation_strategy;
 use wasmtime_api::{Config, Engine, HostRef, Instance, Module, Store};
 use wasmtime_environ::{cache_create_new_config, cache_init};
 use wasmtime_interface_types::ModuleData;
@@ -62,8 +63,8 @@ including calling the start function if one is present. Additional functions
 given with --invoke are then called.
 
 Usage:
-    wasmtime [-odg] [--enable-simd] [--wasi-c] [--disable-cache | --cache-config=<cache_config_file>] [--preload=<wasm>...] [--env=<env>...] [--dir=<dir>...] [--mapdir=<mapping>...] <file> [<arg>...]
-    wasmtime [-odg] [--enable-simd] [--wasi-c] [--disable-cache | --cache-config=<cache_config_file>] [--env=<env>...] [--dir=<dir>...] [--mapdir=<mapping>...] --invoke=<fn> <file> [<arg>...]
+    wasmtime [-odg] [--enable-simd] [--wasi-c] [--disable-cache | --cache-config=<cache_config_file>] [--preload=<wasm>...] [--env=<env>...] [--dir=<dir>...] [--mapdir=<mapping>...] [--always-lightbeam | --always-cranelift] <file> [<arg>...]
+    wasmtime [-odg] [--enable-simd] [--wasi-c] [--disable-cache | --cache-config=<cache_config_file>] [--env=<env>...] [--dir=<dir>...] [--mapdir=<mapping>...] --invoke=<fn> [--always-lightbeam | --always-cranelift] <file> [<arg>...]
     wasmtime --create-cache-config [--cache-config=<cache_config_file>]
     wasmtime --help | --version
 
@@ -80,6 +81,8 @@ Options:
                         instead of default one
     -g                  generate debug information
     -d, --debug         enable debug output on stderr/stdout
+    --always-lightbeam  use Lightbeam for all compilation
+    --always-cranelift  use Cranelift for all compilation
     --enable-simd       enable proposed SIMD instructions
     --wasi-c            enable the wasi-c implementation of WASI
     --preload=<wasm>    load an additional wasm module before loading the main module
@@ -102,6 +105,8 @@ struct Args {
     flag_debug: bool,
     flag_g: bool,
     flag_enable_simd: bool,
+    flag_always_lightbeam: bool,
+    flag_always_cranelift: bool,
     flag_invoke: Option<String>,
     flag_preload: Vec<String>,
     flag_env: Vec<String>,
@@ -281,7 +286,16 @@ fn rmain() -> Result<(), Error> {
         flag_builder.set("opt_level", "speed")?;
     }
 
-    let config = Config::new(settings::Flags::new(flag_builder), features, debug_info);
+    // Decide how to compile.
+    let strategy =
+        pick_compilation_strategy(args.flag_always_cranelift, args.flag_always_lightbeam);
+
+    let config = Config::new(
+        settings::Flags::new(flag_builder),
+        features,
+        debug_info,
+        strategy,
+    );
     let engine = HostRef::new(Engine::new(config));
     let store = HostRef::new(Store::new(engine));
 

src/bin/wast.rs

@@ -33,8 +33,9 @@ use pretty_env_logger;
 use serde::Deserialize;
 use std::path::Path;
 use std::process;
+use wasmtime::pick_compilation_strategy;
 use wasmtime_environ::{cache_create_new_config, cache_init};
-use wasmtime_jit::{CompilationStrategy, Compiler, Features};
+use wasmtime_jit::{Compiler, Features};
 use wasmtime_wast::WastContext;
 
 const USAGE: &str = "
@@ -153,17 +154,8 @@ fn main() {
     }
 
     // Decide how to compile.
-    let strategy = match (args.flag_always_lightbeam, args.flag_always_cranelift) {
-        #[cfg(feature = "lightbeam")]
-        (true, false) => CompilationStrategy::AlwaysLightbeam,
-        #[cfg(not(feature = "lightbeam"))]
-        (true, false) => panic!("--always-lightbeam given, but Lightbeam support is not enabled"),
-        (false, true) => CompilationStrategy::AlwaysCranelift,
-        (false, false) => CompilationStrategy::Auto,
-        (true, true) => {
-            panic!("Can't enable --always-cranelift and --always-lightbeam at the same time")
-        }
-    };
+    let strategy =
+        pick_compilation_strategy(args.flag_always_cranelift, args.flag_always_lightbeam);
 
     let isa = isa_builder.finish(settings::Flags::new(flag_builder));
     let engine = Compiler::new(isa, strategy);

src/lib.rs

@@ -1,3 +1,23 @@
+use wasmtime_jit::CompilationStrategy;
+
+pub fn pick_compilation_strategy(
+    always_cranelift: bool,
+    always_lightbeam: bool,
+) -> CompilationStrategy {
+    // Decide how to compile.
+    match (always_lightbeam, always_cranelift) {
+        #[cfg(feature = "lightbeam")]
+        (true, false) => CompilationStrategy::AlwaysLightbeam,
+        #[cfg(not(feature = "lightbeam"))]
+        (true, false) => panic!("--always-lightbeam given, but Lightbeam support is not enabled"),
+        (false, true) => CompilationStrategy::AlwaysCranelift,
+        (false, false) => CompilationStrategy::Auto,
+        (true, true) => {
+            panic!("Can't enable --always-cranelift and --always-lightbeam at the same time")
+        }
+    }
+}
+
 pub fn init_file_per_thread_logger(prefix: &'static str) {
     file_per_thread_logger::initialize(prefix);
 

wasmtime-api/src/context.rs

@@ -22,8 +22,13 @@ impl Context {
         }
     }
 
-    pub fn create(flags: settings::Flags, features: Features, debug_info: bool) -> Context {
-        Context::new(create_compiler(flags), features, debug_info)
+    pub fn create(
+        flags: settings::Flags,
+        features: Features,
+        debug_info: bool,
+        strategy: CompilationStrategy,
+    ) -> Context {
+        Context::new(create_compiler(flags, strategy), features, debug_info)
     }
 
     pub(crate) fn debug_info(&self) -> bool {
@@ -52,12 +57,12 @@ impl PartialEq for Context {
     }
 }
 
-pub(crate) fn create_compiler(flags: settings::Flags) -> Compiler {
+pub(crate) fn create_compiler(flags: settings::Flags, strategy: CompilationStrategy) -> Compiler {
     let isa = {
         let isa_builder =
             cranelift_native::builder().expect("host machine is not a supported target");
         isa_builder.finish(flags)
     };
 
-    Compiler::new(isa, CompilationStrategy::Auto)
+    Compiler::new(isa, strategy)
 }

wasmtime-api/src/runtime.rs

@@ -6,7 +6,7 @@ use crate::context::{create_compiler, Context};
 use crate::r#ref::HostRef;
 
 use cranelift_codegen::{ir, settings};
-use wasmtime_jit::Features;
+use wasmtime_jit::{CompilationStrategy, Features};
 
 // Runtime Environment
 
@@ -21,6 +21,7 @@ pub struct Config {
     flags: settings::Flags,
     features: Features,
     debug_info: bool,
+    strategy: CompilationStrategy,
 }
 
 impl Config {
@@ -29,14 +30,21 @@ impl Config {
             debug_info: false,
             features: Default::default(),
             flags: default_flags(),
+            strategy: CompilationStrategy::Auto,
         }
     }
 
-    pub fn new(flags: settings::Flags, features: Features, debug_info: bool) -> Config {
+    pub fn new(
+        flags: settings::Flags,
+        features: Features,
+        debug_info: bool,
+        strategy: CompilationStrategy,
+    ) -> Config {
         Config {
             flags,
             features,
             debug_info,
+            strategy,
         }
     }
 
@@ -51,6 +59,10 @@ impl Config {
     pub(crate) fn features(&self) -> &Features {
         &self.features
     }
+
+    pub(crate) fn strategy(&self) -> CompilationStrategy {
+        self.strategy
+    }
 }
 
 // Engine
@@ -74,7 +86,7 @@ impl Engine {
 
     pub fn create_wasmtime_context(&self) -> wasmtime_jit::Context {
         let flags = self.config.flags().clone();
-        wasmtime_jit::Context::new(Box::new(create_compiler(flags)))
+        wasmtime_jit::Context::new(Box::new(create_compiler(flags, self.config.strategy())))
     }
 }
 
@@ -92,9 +104,10 @@ impl Store {
         let flags = engine.borrow().config().flags().clone();
         let features = engine.borrow().config().features().clone();
         let debug_info = engine.borrow().config().debug_info();
+        let strategy = engine.borrow().config().strategy();
         Store {
             engine,
-            context: Context::create(flags, features, debug_info),
+            context: Context::create(flags, features, debug_info, strategy),
             global_exports: Rc::new(RefCell::new(HashMap::new())),
             signature_cache: HashMap::new(),
         }