[wasm-hints] Verify Baseline/Top Tier Finished

Verify that baseline and top tier compilation are finished when
expected. Test cases will use the newly exposed functions
{baseline_compilation_finished} and {top_tier_compilation_finished} for
this.

Bug: v8:9003
Change-Id: I023af3390ed5e087a3b40efe7c340d7e93071a51
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1581941Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Frederik Gossen <frgossen@google.com>
Cr-Commit-Position: refs/heads/master@{#61010}

src/wasm/compilation-environment.h

@@ -119,6 +119,8 @@ class CompilationState {
   void AddCallback(callback_t);
 
   bool failed() const;
+  V8_EXPORT_PRIVATE bool baseline_compilation_finished() const;
+  V8_EXPORT_PRIVATE bool top_tier_compilation_finished() const;
 
   void OnFinishedUnit(WasmCode*);
   void OnFinishedUnits(Vector<WasmCode*>);

src/wasm/module-compiler.cc

@@ -338,6 +338,12 @@ class CompilationStateImpl {
     return outstanding_baseline_functions_ == 0;
   }
 
+  bool top_tier_compilation_finished() const {
+    base::MutexGuard guard(&callbacks_mutex_);
+    DCHECK_LE(outstanding_baseline_functions_, outstanding_top_tier_functions_);
+    return outstanding_top_tier_functions_ == 0;
+  }
+
   CompileMode compile_mode() const { return compile_mode_; }
   Counters* counters() const { return async_counters_.get(); }
   WasmFeatures* detected_features() { return &detected_features_; }
@@ -458,6 +464,14 @@ void CompilationState::AddCallback(CompilationState::callback_t callback) {
 
 bool CompilationState::failed() const { return Impl(this)->failed(); }
 
+bool CompilationState::baseline_compilation_finished() const {
+  return Impl(this)->baseline_compilation_finished();
+}
+
+bool CompilationState::top_tier_compilation_finished() const {
+  return Impl(this)->top_tier_compilation_finished();
+}
+
 void CompilationState::OnFinishedUnit(WasmCode* code) {
   Impl(this)->OnFinishedUnit(code);
 }

test/cctest/wasm/test-run-wasm-module.cc

@@ -125,9 +125,11 @@ TEST(Run_WasmModule_CompilationHintsLazy) {
     CHECK(!module.is_null());
 
     // Lazy function was not invoked and therefore not compiled yet.
-    int func_index = 0;
+    static const int kFuncIndex = 0;
     NativeModule* native_module = module.ToHandleChecked()->native_module();
-    CHECK(!native_module->HasCode(func_index));
+    CHECK(!native_module->HasCode(kFuncIndex));
+    auto* compilation_state = native_module->compilation_state();
+    CHECK(compilation_state->baseline_compilation_finished());
 
     // Instantiate and invoke function.
     MaybeHandle<WasmInstanceObject> instance =
@@ -139,14 +141,15 @@ TEST(Run_WasmModule_CompilationHintsLazy) {
     CHECK_EQ(kReturnValue, result);
 
     // Lazy function was invoked and therefore compiled.
-    CHECK(native_module->HasCode(func_index));
+    CHECK(native_module->HasCode(kFuncIndex));
     WasmCodeRefScope code_ref_scope;
-    ExecutionTier actual_tier = native_module->GetCode(func_index)->tier();
+    ExecutionTier actual_tier = native_module->GetCode(kFuncIndex)->tier();
     static_assert(ExecutionTier::kInterpreter < ExecutionTier::kLiftoff &&
                       ExecutionTier::kLiftoff < ExecutionTier::kTurbofan,
                   "Assume an order on execution tiers");
     ExecutionTier baseline_tier = ExecutionTier::kLiftoff;
     CHECK_LE(baseline_tier, actual_tier);
+    CHECK(compilation_state->baseline_compilation_finished());
   }
   Cleanup();
 }
@@ -183,13 +186,16 @@ TEST(Run_WasmModule_CompilationHintsNoTiering) {
     CHECK(!module.is_null());
 
     // Synchronous compilation finished and no tiering units were initialized.
-    int func_index = 0;
+    static const int kFuncIndex = 0;
     NativeModule* native_module = module.ToHandleChecked()->native_module();
-    CHECK(native_module->HasCode(func_index));
-    WasmCodeRefScope code_ref_scope;
+    CHECK(native_module->HasCode(kFuncIndex));
     ExecutionTier expected_tier = ExecutionTier::kLiftoff;
-    ExecutionTier actual_tier = native_module->GetCode(func_index)->tier();
+    WasmCodeRefScope code_ref_scope;
+    ExecutionTier actual_tier = native_module->GetCode(kFuncIndex)->tier();
     CHECK_EQ(expected_tier, actual_tier);
+    auto* compilation_state = native_module->compilation_state();
+    CHECK(compilation_state->baseline_compilation_finished());
+    CHECK(compilation_state->top_tier_compilation_finished());
   }
   Cleanup();
 }
@@ -225,19 +231,36 @@ TEST(Run_WasmModule_CompilationHintsTierUp) {
         isolate, &thrower, ModuleWireBytes(buffer.begin(), buffer.end()));
     CHECK(!module.is_null());
 
-    // Expect code baseline code or top tier code.
-    int func_index = 0;
+    // Expect baseline or top tier code.
+    static const int kFuncIndex = 0;
     NativeModule* native_module = module.ToHandleChecked()->native_module();
-    CHECK(native_module->HasCode(func_index));
-    WasmCodeRefScope code_ref_scope;
-    ExecutionTier actual_tier = native_module->GetCode(func_index)->tier();
+    auto* compilation_state = native_module->compilation_state();
     static_assert(ExecutionTier::kInterpreter < ExecutionTier::kLiftoff &&
                       ExecutionTier::kLiftoff < ExecutionTier::kTurbofan,
                   "Assume an order on execution tiers");
     ExecutionTier baseline_tier = ExecutionTier::kLiftoff;
-    CHECK_LE(baseline_tier, actual_tier);
+    {
+      CHECK(native_module->HasCode(kFuncIndex));
+      WasmCodeRefScope code_ref_scope;
+      ExecutionTier actual_tier = native_module->GetCode(kFuncIndex)->tier();
+      CHECK_LE(baseline_tier, actual_tier);
+      CHECK(compilation_state->baseline_compilation_finished());
+    }
+
+    // Busy wait for top tier compilation to finish.
+    while (!compilation_state->top_tier_compilation_finished()) {
+    }
+
+    // Expect top tier code.
     ExecutionTier top_tier = ExecutionTier::kTurbofan;
-    CHECK_LE(actual_tier, top_tier);
+    {
+      CHECK(native_module->HasCode(kFuncIndex));
+      WasmCodeRefScope code_ref_scope;
+      ExecutionTier actual_tier = native_module->GetCode(kFuncIndex)->tier();
+      CHECK_EQ(top_tier, actual_tier);
+      CHECK(compilation_state->baseline_compilation_finished());
+      CHECK(compilation_state->top_tier_compilation_finished());
+    }
   }
   Cleanup();
 }