Move wasm file format code into a submodule

compiler/gen_wasm/src/backend.rs

@@ -6,11 +6,10 @@ use roc_module::symbol::Symbol;
 use roc_mono::ir::{CallType, Expr, JoinPointId, Literal, Proc, Stmt};
 use roc_mono::layout::{Builtin, Layout};
 
-use crate::code_builder::{BlockType, CodeBuilder, ValueType};
 use crate::layout::WasmLayout;
-use crate::module_builder::{Signature, WasmModule};
 use crate::storage::{Storage, StoredValue, StoredValueKind};
-use crate::{copy_memory, CopyMemoryConfig, Env, LocalId, PTR_TYPE};
+use crate::wasm_module::{BlockType, CodeBuilder, LocalId, Signature, ValueType, WasmModule};
+use crate::{copy_memory, CopyMemoryConfig, Env, PTR_TYPE};
 
 // Don't allocate any constant data at address zero or near it. Would be valid, but bug-prone.
 // Follow Emscripten's example by using 1kB (4 bytes would probably do)

compiler/gen_wasm/src/layout.rs

@@ -1,6 +1,6 @@
 use roc_mono::layout::{Layout, UnionLayout};
 
-use crate::{code_builder::ValueType, PTR_SIZE, PTR_TYPE};
+use crate::{wasm_module::ValueType, PTR_SIZE, PTR_TYPE};
 
 // See README for background information on Wasm locals, memory and function calls
 #[derive(Debug, Clone)]

compiler/gen_wasm/src/lib.rs

@@ -1,11 +1,8 @@
 mod backend;
-pub mod code_builder;
 pub mod from_wasm32_memory;
 mod layout;
-pub mod module_builder;
-pub mod opcodes;
-pub mod serialize;
 mod storage;
+pub mod wasm_module;
 
 use bumpalo::{self, collections::Vec, Bump};
 
@@ -15,9 +12,9 @@ use roc_mono::ir::{Proc, ProcLayout};
 use roc_mono::layout::LayoutIds;
 
 use crate::backend::WasmBackend;
-use crate::code_builder::{Align, CodeBuilder, ValueType};
+use crate::wasm_module::{
-use crate::module_builder::{
+    Align, CodeBuilder, Export, ExportType, Global, GlobalInitValue, GlobalType, LinkingSubSection,
-    Export, ExportType, Global, GlobalInitValue, GlobalType, LinkingSubSection, SymInfo, WasmModule,
+    LocalId, SymInfo, ValueType, WasmModule,
 };
 
 const PTR_SIZE: u32 = 4;
@@ -26,13 +23,6 @@ const PTR_TYPE: ValueType = ValueType::I32;
 pub const STACK_POINTER_GLOBAL_ID: u32 = 0;
 pub const FRAME_ALIGNMENT_BYTES: i32 = 16;
 
-/// Code section ID from spec
-/// https://webassembly.github.io/spec/core/binary/modules.html#sections
-pub const CODE_SECTION_ID: u8 = 10;
-
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub struct LocalId(pub u32);
-
 pub struct Env<'a> {
     pub arena: &'a Bump,
     pub interns: Interns,

compiler/gen_wasm/src/storage.rs

@@ -4,9 +4,9 @@ use bumpalo::Bump;
 use roc_collections::all::MutMap;
 use roc_module::symbol::Symbol;
 
-use crate::code_builder::{CodeBuilder, ValueType, VirtualMachineSymbolState};
 use crate::layout::WasmLayout;
-use crate::{copy_memory, round_up_to_alignment, CopyMemoryConfig, LocalId, PTR_SIZE, PTR_TYPE};
+use crate::wasm_module::{CodeBuilder, LocalId, ValueType, VirtualMachineSymbolState};
+use crate::{copy_memory, round_up_to_alignment, CopyMemoryConfig, PTR_SIZE, PTR_TYPE};
 
 pub enum StoredValueKind {
     Parameter,
@@ -291,7 +291,7 @@ impl<'a> Storage<'a> {
             | StoredValue::Local {
                 value_type, size, ..
             } => {
-                use crate::code_builder::Align::*;
+                use crate::wasm_module::Align::*;
                 code_builder.get_local(to_ptr);
                 self.load_symbols(code_builder, &[from_symbol]);
                 match (value_type, size) {

compiler/gen_wasm/src/wasm_module/code_builder.rs

@@ -5,10 +5,13 @@ use std::fmt::Debug;
 
 use roc_module::symbol::Symbol;
 
-use crate::module_builder::{IndexRelocType, RelocationEntry};
+use super::opcodes::*;
-use crate::opcodes::*;
+use super::sections::{IndexRelocType, RelocationEntry};
-use crate::serialize::{SerialBuffer, Serialize};
+use super::serialize::{SerialBuffer, Serialize};
-use crate::{round_up_to_alignment, LocalId, FRAME_ALIGNMENT_BYTES, STACK_POINTER_GLOBAL_ID};
+use crate::{round_up_to_alignment, FRAME_ALIGNMENT_BYTES, STACK_POINTER_GLOBAL_ID};
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub struct LocalId(pub u32);
 
 /// Wasm value type. (Rust representation matches Wasm encoding)
 #[repr(u8)]

compiler/gen_wasm/src/wasm_module/mod.rs

@@ -0,0 +1,12 @@
+pub mod code_builder;
+pub mod opcodes;
+pub mod sections;
+pub mod serialize;
+
+pub use code_builder::{
+    Align, BlockType, CodeBuilder, LocalId, ValueType, VirtualMachineSymbolState,
+};
+pub use sections::{
+    Export, ExportType, Global, GlobalInitValue, GlobalType, LinkingSubSection, Signature, SymInfo,
+    WasmModule,
+};

compiler/gen_wasm/src/wasm_module/sections.rs

@@ -1,9 +1,9 @@
 use bumpalo::collections::vec::Vec;
 use bumpalo::Bump;
 
-use crate::code_builder::{Align, CodeBuilder, ValueType};
+use super::opcodes;
-use crate::opcodes;
+use super::serialize::{SerialBuffer, Serialize};
-use crate::serialize::{SerialBuffer, Serialize};
+use super::{Align, CodeBuilder, ValueType};
 
 /*******************************************************************
  *
@@ -920,16 +920,6 @@ impl<'a> Serialize for LinkingSection<'a> {
  * https://webassembly.github.io/spec/core/binary/modules.html
  *
  *******************************************************************/
-pub struct RocUnusedSection {}
-impl Serialize for RocUnusedSection {
-    fn serialize<T: SerialBuffer>(&self, _buffer: &mut T) {}
-}
-impl Default for RocUnusedSection {
-    fn default() -> Self {
-        RocUnusedSection {}
-    }
-}
-
 pub struct WasmModule<'a> {
     pub types: TypeSection<'a>,
     pub import: ImportSection<'a>,
@@ -953,13 +943,6 @@ pub struct WasmModule<'a> {
     pub reloc_data: RelocationSection<'a>,
 }
 
-fn maybe_increment_section(size: usize, prev_size: &mut usize, index: &mut u32) {
-    if size > *prev_size {
-        *index += 1;
-        *prev_size = size;
-    }
-}
-
 impl<'a> WasmModule<'a> {
     pub const WASM_VERSION: u32 = 1;
 
@@ -1040,3 +1023,10 @@ impl<'a> WasmModule<'a> {
         self.reloc_data.serialize(buffer);
     }
 }
+
+fn maybe_increment_section(size: usize, prev_size: &mut usize, index: &mut u32) {
+    if size > *prev_size {
+        *index += 1;
+        *prev_size = size;
+    }
+}

compiler/test_wasm/src/helpers/wasm32_test_result.rs

@@ -1,9 +1,10 @@
 use bumpalo::collections::Vec;
 
-use roc_gen_wasm::code_builder::{Align, CodeBuilder, ValueType};
 use roc_gen_wasm::from_wasm32_memory::FromWasm32Memory;
-use roc_gen_wasm::module_builder::{Export, ExportType, Signature, WasmModule};
+use roc_gen_wasm::wasm_module::opcodes;
-use roc_gen_wasm::LocalId;
+use roc_gen_wasm::wasm_module::{
+    Align, CodeBuilder, Export, ExportType, LocalId, Signature, ValueType, WasmModule,
+};
 use roc_std::{RocDec, RocList, RocOrder, RocStr};
 
 pub trait Wasm32TestResult {
@@ -42,7 +43,7 @@ macro_rules! build_wrapper_body_primitive {
 
             code_builder.get_local(frame_pointer_id);
             // Raw "call" instruction. Don't bother with symbol & relocation since we're not going to link.
-            code_builder.inst_imm32(roc_gen_wasm::opcodes::CALL, 0, true, main_function_index);
+            code_builder.inst_imm32(opcodes::CALL, 0, true, main_function_index);
             code_builder.$store_instruction($align, 0);
             code_builder.get_local(frame_pointer_id);
 
@@ -70,7 +71,7 @@ fn build_wrapper_body_stack_memory(
 
     code_builder.get_local(local_id);
     // Raw "call" instruction. Don't bother with symbol & relocation since we're not going to link.
-    code_builder.inst_imm32(roc_gen_wasm::opcodes::CALL, 0, true, main_function_index);
+    code_builder.inst_imm32(opcodes::CALL, 0, true, main_function_index);
     code_builder.get_local(local_id);
     code_builder.finalize(local_types, size as i32, frame_pointer);
 }