[wasm] Add trace events for wrapper compilation

This adds a few more trace events, also tracing the number of wrappers.
This can help to understand instantiation time better.

R=ahaas@chromium.org

Bug: v8:12287
Change-Id: Ic1a03b2e278af64908f0dc45cd5db60ecf7c79f5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3226323Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77412}

src/wasm/module-compiler.cc

@@ -3737,6 +3737,7 @@ class CompileJSToWasmWrapperJob final : public JobTask {
 
 void CompileJsToWasmWrappers(Isolate* isolate, const WasmModule* module,
                              Handle<FixedArray>* export_wrappers_out) {
+  TRACE_EVENT0("v8.wasm", "wasm.CompileJsToWasmWrappers");
   *export_wrappers_out = isolate->factory()->NewFixedArray(
       MaxNumExportWrappers(module), AllocationType::kOld);
 
@@ -3757,16 +3758,22 @@ void CompileJsToWasmWrappers(Isolate* isolate, const WasmModule* module,
     }
   }
 
-  auto job =
-      std::make_unique<CompileJSToWasmWrapperJob>(&queue, &compilation_units);
-  if (FLAG_wasm_num_compilation_tasks > 0) {
-    auto job_handle = V8::GetCurrentPlatform()->PostJob(
-        TaskPriority::kUserVisible, std::move(job));
-
-    // Wait for completion, while contributing to the work.
-    job_handle->Join();
-  } else {
-    job->Run(nullptr);
+  {
+    // This is nested inside the event above, so the name can be less
+    // descriptive. It's mainly to log the number of wrappers.
+    TRACE_EVENT1("v8.wasm", "wasm.JsToWasmWrapperCompilation", "num_wrappers",
+                 compilation_units.size());
+    auto job =
+        std::make_unique<CompileJSToWasmWrapperJob>(&queue, &compilation_units);
+    if (FLAG_wasm_num_compilation_tasks > 0) {
+      auto job_handle = V8::GetCurrentPlatform()->PostJob(
+          TaskPriority::kUserVisible, std::move(job));
+
+      // Wait for completion, while contributing to the work.
+      job_handle->Join();
+    } else {
+      job->Run(nullptr);
+    }
   }
 
   // Finalize compilation jobs in the main thread.

src/wasm/module-instantiate.cc

@@ -66,6 +66,7 @@ class CompileImportWrapperJob final : public JobTask {
   }
 
   void Run(JobDelegate* delegate) override {
+    TRACE_EVENT0("v8.wasm", "wasm.CompileImportWrapperJob.Run");
     while (base::Optional<WasmImportWrapperCache::CacheKey> key =
                queue_->pop()) {
       // TODO(wasm): Batch code publishing, to avoid repeated locking and
@@ -1493,6 +1494,8 @@ bool InstanceBuilder::ProcessImportedGlobal(Handle<WasmInstanceObject> instance,
 void InstanceBuilder::CompileImportWrappers(
     Handle<WasmInstanceObject> instance) {
   int num_imports = static_cast<int>(module_->import_table.size());
+  TRACE_EVENT1("v8.wasm", "wasm.CompileImportWrappers", "num_imports",
+               num_imports);
   NativeModule* native_module = instance->module_object().native_module();
   WasmImportWrapperCache::ModificationScope cache_scope(
       native_module->import_wrapper_cache());