0-copy module deserialization

Cargo.toml

@@ -94,7 +94,10 @@ glob = "0.3"
 rustc_version = "0.4"
 
 [dev-dependencies]
-wasmer = { version = "=4.1.1", path = "lib/api", default-features = false, features = [
+wasmer = { version = "=4.1.1", path = "lib/api", features = [
+    "compiler",
+    "singlepass",
+    "sys",
 ] }
 anyhow = "1.0"
 criterion = { version = "0.5", default-features = false }

lib/api/Cargo.toml

@@ -34,6 +34,7 @@ bytes = "1"
 wat = { version = "1.0", optional = true }
 tracing = { version = "0.1", optional = true }
 rustc-demangle = "0.1"
+shared-buffer = "0.1"
 
 # Dependencies and Development Dependencies for `sys`.
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
@@ -67,7 +68,9 @@ macro-wasmer-universal-test = { version = "4.1.1", path = "./macro-wasmer-univer
 # Dependencies and Develoment Dependencies for `js`.
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 # - Mandatory dependencies for `js`.
-wasmer-types = { path = "../types", version = "=4.1.1", default-features = false, features = ["std"] }
+wasmer-types = { path = "../types", version = "=4.1.1", default-features = false, features = [
+  "std",
+] }
 wasm-bindgen = "0.2.74"
 wasm-bindgen-downcast = { version = "0.1.1" }
 js-sys = "0.3.51"
@@ -103,16 +106,10 @@ std = []
 core = ["hashbrown"]
 
 # Features for `sys`.
-sys = [
-  "wasmer-compiler/translator",
-  "wasmer-compiler/compiler",
-  "std",
-]
+sys = ["wasmer-compiler/translator", "wasmer-compiler/compiler", "std"]
 sys-default = ["sys", "wat", "cranelift"]
 # - Compilers.
-compiler = [
-    "sys",
-]
+compiler = ["sys"]
 singlepass = ["compiler", "wasmer-compiler-singlepass"]
 cranelift = ["compiler", "wasmer-compiler-cranelift"]
 llvm = ["compiler", "wasmer-compiler-llvm"]
@@ -127,11 +124,7 @@ js-default = ["js", "std", "wasm-types-polyfill"]
 
 wasm-types-polyfill = ["wasmparser"]
 
-jsc = [
-  "rusty_jsc",
-  "wasm-types-polyfill",
-  "wasmparser",
-]
+jsc = ["rusty_jsc", "wasm-types-polyfill", "wasmparser"]
 
 js-serializable-module = []
 
@@ -149,17 +142,17 @@ static-artifact-create = ["wasmer-compiler/static-artifact-create"]
 
 [package.metadata.docs.rs]
 features = [
-    "compiler",
-    "core",
-    "cranelift",
-    "engine",
-    "jit",
-    "singlepass",
-    "static-artifact-create",
-    "static-artifact-load",
-    "sys",
-    "sys-default",
-    "wasmer-artifact-create",
-    "wasmer-artifact-load",
+  "compiler",
+  "core",
+  "cranelift",
+  "engine",
+  "jit",
+  "singlepass",
+  "static-artifact-create",
+  "static-artifact-load",
+  "sys",
+  "sys-default",
+  "wasmer-artifact-create",
+  "wasmer-artifact-load",
 ]
 rustc-args = ["--cfg", "docsrs"]

lib/api/src/engine.rs

@@ -5,7 +5,9 @@ use crate::sys::engine as engine_imp;
 #[cfg(feature = "sys")]
 pub(crate) use crate::sys::engine::default_engine;
 #[cfg(feature = "sys")]
-use std::io::Read;
+use crate::IntoBytes;
+#[cfg(feature = "sys")]
+use shared_buffer::OwnedBuffer;
 #[cfg(feature = "sys")]
 use std::path::Path;
 #[cfg(feature = "sys")]
@@ -45,9 +47,12 @@ impl Engine {
     /// See [`Artifact::deserialize_unchecked`].
     pub unsafe fn deserialize_unchecked(
         &self,
-        bytes: &[u8],
+        bytes: impl IntoBytes,
     ) -> Result<Arc<Artifact>, DeserializeError> {
-        Ok(Arc::new(Artifact::deserialize_unchecked(&self.0, bytes)?))
+        Ok(Arc::new(Artifact::deserialize_unchecked(
+            &self.0,
+            bytes.into_bytes().into(),
+        )?))
     }
 
     #[cfg(all(feature = "sys", not(target_arch = "wasm32")))]
@@ -56,8 +61,14 @@ impl Engine {
     ///
     /// # Safety
     /// See [`Artifact::deserialize`].
-    pub unsafe fn deserialize(&self, bytes: &[u8]) -> Result<Arc<Artifact>, DeserializeError> {
-        Ok(Arc::new(Artifact::deserialize(&self.0, bytes)?))
+    pub unsafe fn deserialize(
+        &self,
+        bytes: impl IntoBytes,
+    ) -> Result<Arc<Artifact>, DeserializeError> {
+        Ok(Arc::new(Artifact::deserialize(
+            &self.0,
+            bytes.into_bytes().into(),
+        )?))
     }
 
     #[cfg(all(feature = "sys", not(target_arch = "wasm32")))]
@@ -71,13 +82,11 @@ impl Engine {
         &self,
         file_ref: &Path,
     ) -> Result<Arc<Artifact>, DeserializeError> {
-        let mut file = std::fs::File::open(file_ref)?;
-        let mut buffer = Vec::new();
-        // read the whole file
-        file.read_to_end(&mut buffer)?;
+        let file = std::fs::File::open(file_ref)?;
         Ok(Arc::new(Artifact::deserialize_unchecked(
             &self.0,
-            buffer.as_slice(),
+            OwnedBuffer::from_file(&file)
+                .map_err(|e| DeserializeError::Generic(format!("{e:?}")))?,
         )?))
     }
 
@@ -90,11 +99,8 @@ impl Engine {
         &self,
         file_ref: &Path,
     ) -> Result<Arc<Artifact>, DeserializeError> {
-        let mut file = std::fs::File::open(file_ref)?;
-        let mut buffer = Vec::new();
-        // read the whole file
-        file.read_to_end(&mut buffer)?;
-        Ok(Arc::new(Artifact::deserialize(&self.0, buffer.as_slice())?))
+        let bytes = std::fs::read(file_ref)?;
+        Ok(Arc::new(Artifact::deserialize(&self.0, bytes.into())?))
     }
 }
 

lib/api/src/sys/engine.rs

@@ -1,9 +1,12 @@
+use std::{path::Path, sync::Arc};
+
+use shared_buffer::OwnedBuffer;
 pub use wasmer_compiler::{
     Artifact, BaseTunables, CompilerConfig, Engine, EngineBuilder, Tunables,
 };
 #[cfg(feature = "compiler")]
 use wasmer_types::Features;
-use wasmer_types::Target;
+use wasmer_types::{DeserializeError, Target};
 
 /// Returns the default engine for the Sys engine
 pub(crate) fn default_engine() -> Engine {
@@ -83,6 +86,26 @@ pub trait NativeEngineExt {
 
     /// Get a reference to attached Tunable of this engine
     fn tunables(&self) -> &dyn Tunables;
+
+    /// Load a serialized WebAssembly module from a memory mapped file and deserialize it.
+    ///
+    /// NOTE: you should almost always prefer [`Self::deserialize_from_mmapped_file`].
+    ///
+    /// # Safety
+    /// See [`Artifact::deserialize_unchecked`].
+    unsafe fn deserialize_from_mmapped_file_unchecked(
+        &self,
+        file_ref: &Path,
+    ) -> Result<Arc<Artifact>, DeserializeError>;
+
+    /// Load a serialized WebAssembly module from a memory mapped file and deserialize it.
+    ///
+    /// # Safety
+    /// See [`Artifact::deserialize`].
+    unsafe fn deserialize_from_mmapped_file(
+        &self,
+        file_ref: &Path,
+    ) -> Result<Arc<Artifact>, DeserializeError>;
 }
 
 impl NativeEngineExt for crate::engine::Engine {
@@ -106,4 +129,27 @@ impl NativeEngineExt for crate::engine::Engine {
     fn tunables(&self) -> &dyn Tunables {
         self.0.tunables()
     }
+
+    unsafe fn deserialize_from_mmapped_file_unchecked(
+        &self,
+        file_ref: &Path,
+    ) -> Result<Arc<Artifact>, DeserializeError> {
+        let bytes = std::fs::read(file_ref)?;
+        Ok(Arc::new(Artifact::deserialize_unchecked(
+            &self.0,
+            bytes.into(),
+        )?))
+    }
+
+    unsafe fn deserialize_from_mmapped_file(
+        &self,
+        file_ref: &Path,
+    ) -> Result<Arc<Artifact>, DeserializeError> {
+        let file = std::fs::File::open(file_ref)?;
+        Ok(Arc::new(Artifact::deserialize(
+            &self.0,
+            OwnedBuffer::from_file(&file)
+                .map_err(|e| DeserializeError::Generic(format!("{e:?}")))?,
+        )?))
+    }
 }

lib/api/src/sys/module.rs

@@ -79,7 +79,7 @@ impl Module {
             .as_engine_ref()
             .engine()
             .0
-            .deserialize_unchecked(&bytes)?;
+            .deserialize_unchecked(bytes.into())?;
         Ok(Self::from_artifact(artifact))
     }
 
@@ -88,7 +88,11 @@ impl Module {
         bytes: impl IntoBytes,
     ) -> Result<Self, DeserializeError> {
         let bytes = bytes.into_bytes();
-        let artifact = engine.as_engine_ref().engine().0.deserialize(&bytes)?;
+        let artifact = engine
+            .as_engine_ref()
+            .engine()
+            .0
+            .deserialize(bytes.into())?;
         Ok(Self::from_artifact(artifact))
     }
 

lib/compiler/Cargo.toml

@@ -32,6 +32,11 @@ cfg-if = "1.0"
 leb128 = "0.2"
 enum-iterator = "0.7.0"
 
+bytes = "1.0"
+self_cell = "1.0"
+rkyv = { version = "0.7.40", features = ["indexmap", "validation", "strict"] }
+shared-buffer = "0.1"
+
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 wasmer-vm = { path = "../vm", version = "=4.1.1" }
 region = { version = "3.0" }
@@ -40,7 +45,7 @@ region = { version = "3.0" }
 winapi = { version = "0.3", features = ["winnt", "impl-default"] }
 
 [features]
-default = ["std" ]
+default = ["std"]
 # This feature is for compiler implementors, it enables using `Compiler` and
 # `CompilerConfig`, as well as the included wasmparser.
 # Disable this feature if you just want a headless engine.