[wasm] Add some basic trace events

This adds trace events for Liftoff compilation, Turbofan compilation,
instantiation and running the start function. These are basic
operations that help to understand the startup behaviour of WebAssembly
modules.

R=ahaas@chromium.org

Change-Id: I0c0544cfd2d03de1783fa1d3a5897d3b8ef09e05
Reviewed-on: https://chromium-review.googlesource.com/1134768
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54434}

src/compiler/wasm-compiler.cc

@@ -37,6 +37,7 @@
 #include "src/isolate-inl.h"
 #include "src/log-inl.h"
 #include "src/optimized-compilation-info.h"
+#include "src/tracing/trace-event.h"
 #include "src/trap-handler/trap-handler.h"
 #include "src/wasm/function-body-decoder.h"
 #include "src/wasm/function-compiler.h"
@@ -5154,6 +5155,8 @@ Vector<const char> GetDebugName(Zone* zone, wasm::WasmName name, int index) {
 }  // namespace
 
 void TurbofanWasmCompilationUnit::ExecuteCompilation() {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.wasm"),
+               "ExecuteTurbofanCompilation");
   double decode_ms = 0;
   size_t node_count = 0;
 

src/wasm/baseline/liftoff-compiler.cc

@@ -11,6 +11,7 @@
 #include "src/compiler/wasm-compiler.h"
 #include "src/counters.h"
 #include "src/macro-assembler-inl.h"
+#include "src/tracing/trace-event.h"
 #include "src/wasm/baseline/liftoff-assembler.h"
 #include "src/wasm/function-body-decoder-impl.h"
 #include "src/wasm/function-compiler.h"
@@ -1832,6 +1833,8 @@ class LiftoffCompiler {
 }  // namespace
 
 bool LiftoffCompilationUnit::ExecuteCompilation() {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.wasm"),
+               "ExecuteLiftoffCompilation");
   base::ElapsedTimer compile_timer;
   if (FLAG_trace_wasm_decode_time) {
     compile_timer.Start();

src/wasm/module-compiler.cc

@@ -13,6 +13,7 @@
 #include "src/counters.h"
 #include "src/identity-map.h"
 #include "src/property-descriptor.h"
+#include "src/tracing/trace-event.h"
 #include "src/trap-handler/trap-handler.h"
 #include "src/wasm/module-decoder.h"
 #include "src/wasm/streaming-decoder.h"
@@ -577,6 +578,7 @@ void InitializeCompilationUnits(NativeModule* native_module) {
 
 void FinishCompilationUnits(CompilationState* compilation_state,
                             ErrorThrower* thrower) {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.wasm"), "FinishCompilationUnits");
   while (true) {
     if (compilation_state->failed()) break;
     std::unique_ptr<WasmCompilationUnit> unit =
@@ -959,6 +961,7 @@ InstanceBuilder::InstanceBuilder(Isolate* isolate, ErrorThrower* thrower,
 
 // Build an instance, in all of its glory.
 MaybeHandle<WasmInstanceObject> InstanceBuilder::Build() {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.wasm"), "InstanceBuilder::Build");
   // Check that an imports argument was provided, if the module requires it.
   // No point in continuing otherwise.
   if (!module_->import_table.empty() && ffi_.is_null()) {
@@ -1235,6 +1238,8 @@ MaybeHandle<WasmInstanceObject> InstanceBuilder::Build() {
 }
 
 bool InstanceBuilder::ExecuteStartFunction() {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.wasm"),
+               "InstanceBuilder::ExecuteStartFunction");
   if (start_function_.is_null()) return true;  // No start function.
 
   HandleScope scope(isolate_);