Add support for Wasm multi-memory proposal (#1191)

* add Memory index type

* adjust load instructions for multi-memory proposal

* improve docs for 16-bit offset variants

* re-design store instruction for multi-memory proposal

* minor fix in store instruction docs

* adjust executor to support re-designed load instructions

* fix docs for fetch_ptr_and_offset

* adjust executor to support new and re-designed store instructions

* optionally encode Instruction::MemoryIndex after load_at instructions

* implement translation of new load instruction

* apply clippy suggestion

* apply rustfmt

* fix 32_store16_imm snake name

* teach Wasmi translator to encode the new store instruction

* update encoding docs of store_at instructions

* add multi-memory support to wasmi::Config

* support optional MemoryIndex param for store instrs in executor

* add #[inline] to fetch_optional_memory

* improve docs of TableFill instructions

* update docs for bulk memory instructions

* implement multi-memory support for bulk-memory instrs in translator and executor

* disable multi-memory for MVP test config

* fix bug in load instruction translation

* apply rustfmt

* fix memory_size translation tests

* update and fix load instruction translation tests

* fix translation of memory.grow

* update and fix memory.grow translation tests

* update and fix memory.copy translation tests

* fix and adjust memory.fill translation tests

* fix and adjust memory.init translation tests

* adjust and fix some store instruction translation tests

* add store_imm16 translation test

* update and fix remaining store translation tests

* fix bug in executor for memory.grow

* fix clippy warnings

* remove commented out code

* remove commented out code (2)

* remove outdated debug assertion

* include multi-memory spec tests

* update Wasm spec testsuite by 1 rev

* fix bug in memory.copy execution

* improve naming of locals

crates/ir/src/immeditate.rs

@@ -448,6 +448,12 @@ impl TryFrom<NonZeroU64> for AnyConst16 {
     }
 }
 
+impl From<i8> for AnyConst16 {
+    fn from(value: i8) -> Self {
+        Self(value as u8 as u16 as i16)
+    }
+}
+
 impl From<i16> for AnyConst16 {
     fn from(value: i16) -> Self {
         Self(value)
@@ -460,6 +466,18 @@ impl From<u16> for AnyConst16 {
     }
 }
 
+impl From<AnyConst16> for i8 {
+    fn from(value: AnyConst16) -> Self {
+        value.0 as i8
+    }
+}
+
+impl From<AnyConst16> for i16 {
+    fn from(value: AnyConst16) -> Self {
+        value.0
+    }
+}
+
 impl From<AnyConst16> for i32 {
     fn from(value: AnyConst16) -> Self {
         Self::from(value.0)

crates/ir/src/index.rs

@@ -20,6 +20,8 @@ macro_rules! for_each_index {
             InternalFunc(pub(crate) u32);
             /// A Wasm global variable index.
             Global(pub(crate) u32);
+            /// A Wasm linear memory index.
+            Memory(pub(crate) u32);
             /// A Wasm table index.
             Table(pub(crate) u32);
             /// A Wasm data segment index.
@@ -30,6 +32,13 @@ macro_rules! for_each_index {
     };
 }
 
+impl Memory {
+    /// Returns `true` if `self` refers to the default linear memory which always is at index 0.
+    pub fn is_default(&self) -> bool {
+        self.0 == 0
+    }
+}
+
 macro_rules! define_index {
     (
         $(

crates/ir/src/lib.rs

@@ -21,11 +21,10 @@ mod tests;
 
 use wasmi_core as core;
 
-use self::immeditate::AnyConst16;
 #[doc(inline)]
 pub use self::{
     error::Error,
-    immeditate::{AnyConst32, Const16, Const32},
+    immeditate::{AnyConst16, AnyConst32, Const16, Const32},
     index::Instr,
     index::Reg,
     primitive::{BlockFuel, BranchOffset, BranchOffset16, Comparator, ComparatorAndOffset, Sign},

crates/ir/src/visit_regs.rs

@@ -84,6 +84,7 @@ impl_host_visitor_for!(
     Func,
     FuncType,
     Global,
+    Memory,
     Table,
     Elem,
     Data,

crates/wasmi/src/engine/config.rs

@@ -23,6 +23,8 @@ pub struct Config {
     saturating_float_to_int: bool,
     /// Is `true` if the [`multi-value`] Wasm proposal is enabled.
     multi_value: bool,
+    /// Is `true` if the [`multi-memory`] Wasm proposal is enabled.
+    multi_memory: bool,
     /// Is `true` if the [`bulk-memory`] Wasm proposal is enabled.
     bulk_memory: bool,
     /// Is `true` if the [`reference-types`] Wasm proposal is enabled.
@@ -176,6 +178,7 @@ impl Default for Config {
             sign_extension: true,
             saturating_float_to_int: true,
             multi_value: true,
+            multi_memory: true,
             bulk_memory: true,
             reference_types: true,
             tail_call: true,
@@ -266,6 +269,18 @@ impl Config {
         self
     }
 
+    /// Enable or disable the [`multi-memory`] Wasm proposal for the [`Config`].
+    ///
+    /// # Note
+    ///
+    /// Enabled by default.
+    ///
+    /// [`multi-memory`]: https://github.com/WebAssembly/multi-memory
+    pub fn wasm_multi_memory(&mut self, enable: bool) -> &mut Self {
+        self.multi_memory = enable;
+        self
+    }
+
     /// Enable or disable the [`bulk-memory`] Wasm proposal for the [`Config`].
     ///
     /// # Note
@@ -419,7 +434,7 @@ impl Config {
             simd: false,
             relaxed_simd: false,
             threads: false,
-            multi_memory: false,
+            multi_memory: self.multi_memory,
             exceptions: false,
             memory64: false,
             memory_control: false,

crates/wasmi/src/engine/executor/cache.rs

@@ -120,9 +120,9 @@ impl CachedInstance {
     ///
     /// It is the callers responsibility to use this method only when the caches are fresh.
     #[inline]
-    pub unsafe fn get_memory(&self, index: u32) -> Option<Memory> {
+    pub unsafe fn get_memory(&self, index: index::Memory) -> Option<Memory> {
         let instance = unsafe { self.as_ref() };
-        instance.get_memory(index)
+        instance.get_memory(u32::from(index))
     }
 
     /// Returns the [`Table`] at the `index` if any.