[wasm] Merge foreground work after compilation

Instead of spawning several foreground tasks, execute the work in a
single chunk.
This will allow us in a follow-up step to remove the deferred handle
scope and pass the handles directly.

R=ahaas@chromium.org

Bug: v8:7921, v8:8423
Change-Id: I4dae6241e2a33e89e304a04cb67c2229c34f7b99
Reviewed-on: https://chromium-review.googlesource.com/c/1402545
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58677}

src/wasm/module-compiler.cc

@@ -2549,12 +2549,11 @@ void AsyncCompileJob::FinishCompile() {
 
   // TODO(bbudge) Allow deserialization without wrapper compilation, so we can
   // just compile wrappers here.
-  if (is_after_deserialization) {
-    DoSync<AsyncCompileJob::FinishModule>();
-  } else {
-    // TODO(wasm): compiling wrappers should be made async as well.
-    DoSync<CompileWrappers>();
+  if (!is_after_deserialization) {
+    // TODO(wasm): compiling wrappers should be made async.
+    CompileWrappers();
   }
+  FinishModule();
 }
 
 void AsyncCompileJob::AsyncCompileFailed(Handle<Object> error_reason) {
@@ -2870,46 +2869,34 @@ class AsyncCompileJob::CompileFailed : public CompileStep {
   Handle<Object> error_reason_;
 };
 
-//==========================================================================
-// Step 5 (sync): Compile JS->wasm wrappers.
-//==========================================================================
-class AsyncCompileJob::CompileWrappers : public CompileStep {
+void AsyncCompileJob::CompileWrappers() {
   // TODO(wasm): Compile all wrappers here, including the start function wrapper
   // and the wrappers for the function table elements.
-  void RunInForeground(AsyncCompileJob* job) override {
-    TRACE_COMPILE("(5) Compile wrappers...\n");
-    // Compile JS->wasm wrappers for exported functions.
-    CompileJsToWasmWrappers(
-        job->isolate_, job->module_object_->native_module()->module(),
-        handle(job->module_object_->export_wrappers(), job->isolate_));
-    job->DoSync<FinishModule>();
+  TRACE_COMPILE("(5) Compile wrappers...\n");
+  // Compile JS->wasm wrappers for exported functions.
+  CompileJsToWasmWrappers(isolate_, module_object_->native_module()->module(),
+                          handle(module_object_->export_wrappers(), isolate_));
+}
+
+void AsyncCompileJob::FinishModule() {
+  TRACE_COMPILE("(6) Finish module...\n");
+  AsyncCompileSucceeded(module_object_);
+
+  size_t num_functions = native_module_->num_functions() -
+                         native_module_->num_imported_functions();
+  auto* compilation_state = Impl(native_module_->compilation_state());
+  if (compilation_state->compile_mode() == CompileMode::kRegular ||
+      num_functions == 0) {
+    // If we do not tier up, the async compile job is done here and
+    // can be deleted.
+    isolate_->wasm_engine()->RemoveCompileJob(this);
+    return;
   }
-};
-
-//==========================================================================
-// Step 6 (sync): Finish the module and resolve the promise.
-//==========================================================================
-class AsyncCompileJob::FinishModule : public CompileStep {
-  void RunInForeground(AsyncCompileJob* job) override {
-    TRACE_COMPILE("(6) Finish module...\n");
-    job->AsyncCompileSucceeded(job->module_object_);
-
-    size_t num_functions = job->native_module_->num_functions() -
-                           job->native_module_->num_imported_functions();
-    auto* compilation_state = Impl(job->native_module_->compilation_state());
-    if (compilation_state->compile_mode() == CompileMode::kRegular ||
-        num_functions == 0) {
-      // If we do not tier up, the async compile job is done here and
-      // can be deleted.
-      job->isolate_->wasm_engine()->RemoveCompileJob(job);
-      return;
-    }
-    DCHECK_EQ(CompileMode::kTiering, compilation_state->compile_mode());
-    if (compilation_state->baseline_compilation_finished()) {
-      job->isolate_->wasm_engine()->RemoveCompileJob(job);
-    }
+  DCHECK_EQ(CompileMode::kTiering, compilation_state->compile_mode());
+  if (compilation_state->baseline_compilation_finished()) {
+    isolate_->wasm_engine()->RemoveCompileJob(this);
   }
-};
+}
 
 AsyncStreamingProcessor::AsyncStreamingProcessor(AsyncCompileJob* job)
     : decoder_(job->enabled_features_),

src/wasm/module-compiler.h

@@ -93,8 +93,6 @@ class AsyncCompileJob {
   class DecodeFail;              // Step 1b (sync)
   class PrepareAndStartCompile;  // Step 2  (sync)
   class CompileFailed;           // Step 4b (sync)
-  class CompileWrappers;         // Step 5  (sync)
-  class FinishModule;            // Step 6  (sync)
 
   friend class AsyncStreamingProcessor;
 
@@ -114,6 +112,10 @@ class AsyncCompileJob {
 
   void AsyncCompileSucceeded(Handle<WasmModuleObject> result);
 
+  void CompileWrappers();
+
+  void FinishModule();
+
   void StartForegroundTask();
   void ExecuteForegroundTaskImmediately();