Wasm: Serialize WasmModule without linking info

compiler/gen_wasm/src/wasm_module/code_builder.rs

@@ -156,6 +156,12 @@ pub struct CodeBuilder<'a> {
     relocations: Vec<'a, RelocationEntry>,
 }
 
+impl<'a> Serialize for CodeBuilder<'a> {
+    fn serialize<T: SerialBuffer>(&self, buffer: &mut T) {
+        self.serialize_without_relocs(buffer);
+    }
+}
+
 #[allow(clippy::new_without_default)]
 impl<'a> CodeBuilder<'a> {
     pub fn new(arena: &'a Bump) -> Self {
@@ -470,6 +476,35 @@ impl<'a> CodeBuilder<'a> {
 
     ***********************************************************/
 
+    /// Serialize all byte vectors in the right order
+    /// Also update relocation offsets relative to the base offset (code section body start)
+    pub fn serialize_without_relocs<T: SerialBuffer>(&self, buffer: &mut T) {
+        buffer.append_slice(&self.inner_length);
+        buffer.append_slice(&self.preamble);
+
+        let mut code_pos = 0;
+        let mut insert_iter = self.insertions.iter();
+        loop {
+            let next_insert = insert_iter.next();
+            let next_pos = match next_insert {
+                Some(Insertion { at, .. }) => *at,
+                None => self.code.len(),
+            };
+
+            buffer.append_slice(&self.code[code_pos..next_pos]);
+
+            match next_insert {
+                Some(Insertion { at, start, end }) => {
+                    buffer.append_slice(&self.insert_bytes[*start..*end]);
+                    code_pos = *at;
+                }
+                None => {
+                    break;
+                }
+            }
+        }
+    }
+
     /// Serialize all byte vectors in the right order
     /// Also update relocation offsets relative to the base offset (code section body start)
     pub fn serialize_with_relocs<T: SerialBuffer>(

compiler/gen_wasm/src/wasm_module/mod.rs

@@ -41,9 +41,29 @@ impl<'a> WasmModule<'a> {
         self.function.add_sig(index);
     }
 
+    /// Serialize the module to bytes
+    /// (not using Serialize trait because it's just one more thing to export)
+    pub fn serialize<T: SerialBuffer>(&self, buffer: &mut T) {
+        buffer.append_u8(0);
+        buffer.append_slice("asm".as_bytes());
+        buffer.write_unencoded_u32(Self::WASM_VERSION);
+
+        self.types.serialize(buffer);
+        self.import.serialize(buffer);
+        self.function.serialize(buffer);
+        self.table.serialize(buffer);
+        self.memory.serialize(buffer);
+        self.global.serialize(buffer);
+        self.export.serialize(buffer);
+        self.start.serialize(buffer);
+        self.element.serialize(buffer);
+        self.code.serialize(buffer);
+        self.data.serialize(buffer);
+    }
+
     /// Serialize the module to bytes
     /// (Mutates some data related to linking)
-    pub fn serialize_mut<T: SerialBuffer>(&mut self, buffer: &mut T) {
+    pub fn serialize_with_linker_data_mut<T: SerialBuffer>(&mut self, buffer: &mut T) {
         buffer.append_u8(0);
         buffer.append_slice("asm".as_bytes());
         buffer.write_unencoded_u32(Self::WASM_VERSION);

compiler/gen_wasm/src/wasm_module/sections.rs

@@ -557,6 +557,21 @@ impl<'a> CodeSection<'a> {
     }
 }
 
+impl<'a> Serialize for CodeSection<'a> {
+    fn serialize<T: SerialBuffer>(&self, buffer: &mut T) {
+        let header_indices = write_section_header(buffer, SectionId::Code);
+        buffer.encode_u32(self.preloaded_count + self.code_builders.len() as u32);
+
+        buffer.append_slice(&self.preloaded_bytes);
+
+        for code_builder in self.code_builders.iter() {
+            code_builder.serialize(buffer);
+        }
+
+        update_section_size(buffer, header_indices);
+    }
+}
+
 /*******************************************************************
  *
  * Data section

compiler/gen_wasm/src/wasm_module/serialize.rs

@@ -3,7 +3,7 @@ use std::{fmt::Debug, iter::FromIterator};
 use bumpalo::collections::vec::Vec;
 use roc_reporting::internal_error;
 
-pub trait Serialize {
+pub(super) trait Serialize {
     fn serialize<T: SerialBuffer>(&self, buffer: &mut T);
 }