1 files changed, 159 insertions, 0 deletions
diff --git a/third_party/rust/cranelift-wasm/src/module_translator.rs b/third_party/rust/cranelift-wasm/src/module_translator.rs
new file mode 100644
index 0000000000..0b1794158f
--- /dev/null
+++ b/third_party/rust/cranelift-wasm/src/module_translator.rs
@@ -0,0 +1,159 @@
+//! Translation skeleton that traverses the whole WebAssembly module and call helper functions
+//! to deal with each part of it.
+use crate::environ::{ModuleEnvironment, WasmResult};
+use crate::sections_translator::{
+    parse_data_section, parse_element_section, parse_export_section, parse_function_section,
+    parse_global_section, parse_import_section, parse_memory_section, parse_name_section,
+    parse_start_section, parse_table_section, parse_type_section,
+};
+use crate::state::ModuleTranslationState;
+use cranelift_codegen::timing;
+use std::prelude::v1::*;
+use wasmparser::{NameSectionReader, Parser, Payload, Validator};
+
+/// Translate a sequence of bytes forming a valid Wasm binary into a list of valid Cranelift IR
+/// [`Function`](cranelift_codegen::ir::Function).
+pub fn translate_module<'data>(
+    data: &'data [u8],
+    environ: &mut dyn ModuleEnvironment<'data>,
+) -> WasmResult<ModuleTranslationState> {
+    let _tt = timing::wasm_translate_module();
+    let mut module_translation_state = ModuleTranslationState::new();
+    let mut validator = Validator::new();
+    validator.wasm_features(environ.wasm_features());
+    let mut stack = Vec::new();
+    let mut modules = 1;
+    let mut cur_module = 0;
+
+    for payload in Parser::new(0).parse_all(data) {
+        match payload? {
+            Payload::Version { num, range } => {
+                validator.version(num, &range)?;
+                environ.module_start(cur_module);
+            }
+            Payload::End => {
+                validator.end()?;
+                environ.module_end(cur_module);
+                if let Some((other, other_index)) = stack.pop() {
+                    validator = other;
+                    cur_module = other_index;
+                }
+            }
+
+            Payload::TypeSection(types) => {
+                validator.type_section(&types)?;
+                parse_type_section(types, &mut module_translation_state, environ)?;
+            }
+
+            Payload::ImportSection(imports) => {
+                validator.import_section(&imports)?;
+                parse_import_section(imports, environ)?;
+            }
+
+            Payload::FunctionSection(functions) => {
+                validator.function_section(&functions)?;
+                parse_function_section(functions, environ)?;
+            }
+
+            Payload::TableSection(tables) => {
+                validator.table_section(&tables)?;
+                parse_table_section(tables, environ)?;
+            }
+
+            Payload::MemorySection(memories) => {
+                validator.memory_section(&memories)?;
+                parse_memory_section(memories, environ)?;
+            }
+
+            Payload::GlobalSection(globals) => {
+                validator.global_section(&globals)?;
+                parse_global_section(globals, environ)?;
+            }
+
+            Payload::ExportSection(exports) => {
+                validator.export_section(&exports)?;
+                parse_export_section(exports, environ)?;
+            }
+
+            Payload::StartSection { func, range } => {
+                validator.start_section(func, &range)?;
+                parse_start_section(func, environ)?;
+            }
+
+            Payload::ElementSection(elements) => {
+                validator.element_section(&elements)?;
+                parse_element_section(elements, environ)?;
+            }
+
+            Payload::CodeSectionStart { count, range, .. } => {
+                validator.code_section_start(count, &range)?;
+                environ.reserve_function_bodies(count, range.start as u64);
+            }
+
+            Payload::CodeSectionEntry(body) => {
+                let func_validator = validator.code_section_entry()?;
+                environ.define_function_body(func_validator, body)?;
+            }
+
+            Payload::DataSection(data) => {
+                validator.data_section(&data)?;
+                parse_data_section(data, environ)?;
+            }
+
+            Payload::DataCountSection { count, range } => {
+                validator.data_count_section(count, &range)?;
+                environ.reserve_passive_data(count)?;
+            }
+
+            Payload::ModuleSection(s) => {
+                validator.module_section(&s)?;
+                environ.reserve_modules(s.get_count());
+            }
+            Payload::InstanceSection(s) => {
+                validator.instance_section(&s)?;
+                unimplemented!("module linking not implemented yet")
+            }
+            Payload::AliasSection(s) => {
+                validator.alias_section(&s)?;
+                unimplemented!("module linking not implemented yet")
+            }
+            Payload::ModuleCodeSectionStart {
+                count,
+                range,
+                size: _,
+            } => {
+                validator.module_code_section_start(count, &range)?;
+            }
+
+            Payload::ModuleCodeSectionEntry { .. } => {
+                let subvalidator = validator.module_code_section_entry();
+                stack.push((validator, cur_module));
+                validator = subvalidator;
+                cur_module = modules;
+                modules += 1;
+            }
+
+            Payload::CustomSection {
+                name: "name",
+                data,
+                data_offset,
+            } => {
+                let result = NameSectionReader::new(data, data_offset)
+                    .map_err(|e| e.into())
+                    .and_then(|s| parse_name_section(s, environ));
+                if let Err(e) = result {
+                    log::warn!("failed to parse name section {:?}", e);
+                }
+            }
+
+            Payload::CustomSection { name, data, .. } => environ.custom_section(name, data)?,
+
+            Payload::UnknownSection { id, range, .. } => {
+                validator.unknown_section(id, &range)?;
+                unreachable!();
+            }
+        }
+    }
+
+    Ok(module_translation_state)
+}