[wasm] Move native context field into {WasmInstanceObject}.

R=clemensh@chromium.org
BUG=v8:7424

Change-Id: I334d0521982e173650da7dd5da0627197dff171b
Reviewed-on: https://chromium-review.googlesource.com/1035124
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52890}

src/compiler/wasm-compiler.cc

@@ -3114,21 +3114,8 @@ bool WasmGraphBuilder::BuildWasmToJSWrapper(Handle<JSReceiver> target,
   Node* callable_node = LOAD_FIXED_ARRAY_SLOT(callables_node, index);
   Node* undefined_node =
       jsgraph()->Constant(handle(isolate->heap()->undefined_value(), isolate));
-
-  Node* compiled_module =
-      LOAD_INSTANCE_FIELD(CompiledModule, MachineType::TaggedPointer());
-  // TODO(wasm): native context is only weak because of recycling compiled
-  // modules.
-  Node* weak_native_context = graph()->NewNode(
-      jsgraph()->machine()->Load(MachineType::TaggedPointer()), compiled_module,
-      jsgraph()->Int32Constant(WasmCompiledModule::kNativeContextOffset -
-                               kHeapObjectTag),
-      *effect_, *control_);
-  Node* native_context = graph()->NewNode(
-      jsgraph()->machine()->Load(MachineType::TaggedPointer()),
-      weak_native_context,
-      jsgraph()->Int32Constant(WeakCell::kValueOffset - kHeapObjectTag),
-      *effect_, *control_);
+  Node* native_context =
+      LOAD_INSTANCE_FIELD(NativeContext, MachineType::TaggedPointer());
 
   if (!wasm::IsJSCompatibleSignature(sig_)) {
     // Throw a TypeError.

src/frames.cc

@@ -1335,8 +1335,7 @@ Handle<String> FrameSummary::WasmFrameSummary::FunctionName() const {
 }
 
 Handle<Context> FrameSummary::WasmFrameSummary::native_context() const {
-  return handle(wasm_instance()->compiled_module()->native_context(),
-                isolate());
+  return handle(wasm_instance()->native_context(), isolate());
 }
 
 FrameSummary::WasmCompiledFrameSummary::WasmCompiledFrameSummary(
@@ -1915,7 +1914,7 @@ int WasmInterpreterEntryFrame::position() const {
 }
 
 Object* WasmInterpreterEntryFrame::context() const {
-  return compiled_module()->native_context();
+  return wasm_instance()->native_context();
 }
 
 Address WasmInterpreterEntryFrame::GetCallerStackPointer() const {

src/objects-debug.cc

@@ -1509,7 +1509,6 @@ void Tuple3::Tuple3Verify() {
 void WasmCompiledModule::WasmCompiledModuleVerify() {
   CHECK(IsWasmCompiledModule());
   VerifyObjectField(kSharedOffset);
-  VerifyObjectField(kNativeContextOffset);
   VerifyObjectField(kExportWrappersOffset);
   VerifyObjectField(kNextInstanceOffset);
   VerifyObjectField(kPrevInstanceOffset);

src/runtime/runtime-wasm.cc

@@ -43,9 +43,7 @@ WasmInstanceObject* GetWasmInstanceOnStackTop(Isolate* isolate) {
 }
 
 Context* GetNativeContextFromWasmInstanceOnStackTop(Isolate* isolate) {
-  return GetWasmInstanceOnStackTop(isolate)
-      ->compiled_module()
-      ->native_context();
+  return GetWasmInstanceOnStackTop(isolate)->native_context();
 }
 
 class ClearThreadInWasmScope {
@@ -79,7 +77,7 @@ RUNTIME_FUNCTION(Runtime_WasmGrowMemory) {
 
   // Set the current isolate's context.
   DCHECK_NULL(isolate->context());
-  isolate->set_context(instance->compiled_module()->native_context());
+  isolate->set_context(instance->native_context());
 
   return *isolate->factory()->NewNumberFromInt(WasmMemoryObject::Grow(
       isolate, handle(instance->memory_object(), isolate), delta_pages));
@@ -248,7 +246,7 @@ RUNTIME_FUNCTION(Runtime_WasmRunInterpreter) {
 
   // Set the current isolate's context.
   DCHECK_NULL(isolate->context());
-  isolate->set_context(instance->compiled_module()->native_context());
+  isolate->set_context(instance->native_context());
 
   // Find the frame pointer of the interpreter entry.
   Address frame_pointer = 0;

src/wasm/module-compiler.cc

@@ -1655,9 +1655,6 @@ MaybeHandle<WasmInstanceObject> InstanceBuilder::Build() {
       TRACE("Reusing existing instance %zu\n",
             compiled_module_->GetNativeModule()->instance_id);
     }
-    Handle<WeakCell> weak_native_context =
-        isolate_->factory()->NewWeakCell(isolate_->native_context());
-    compiled_module_->set_weak_native_context(*weak_native_context);
   }
   base::Optional<wasm::NativeModuleModificationScope>
       native_module_modification_scope;
@@ -3124,9 +3121,9 @@ class AsyncCompileJob::PrepareAndStartCompile : public CompileStep {
               case CompilationEvent::kFinishedBaselineCompilation:
                 if (job->DecrementAndCheckFinisherCount()) {
                   SaveContext saved_context(job->isolate());
-                  job->isolate()->set_context(
-                      job->compiled_module_->native_context());
-
+                  // TODO(mstarzinger): Make {AsyncCompileJob::context} point
+                  // to the native context and also rename to {native_context}.
+                  job->isolate()->set_context(job->context_->native_context());
                   job->FinishCompile();
                 }
                 return;
@@ -3151,8 +3148,7 @@ class AsyncCompileJob::PrepareAndStartCompile : public CompileStep {
                             ->baseline_compilation_finished());
 
                 SaveContext saved_context(job->isolate());
-                job->isolate()->set_context(
-                    job->compiled_module_->native_context());
+                job->isolate()->set_context(job->context_->native_context());
                 Handle<Object> error = thrower->Reify();
 
                 DeferredHandleScope deferred(job->isolate());

src/wasm/wasm-debug.cc

@@ -774,8 +774,7 @@ Handle<JSFunction> WasmDebugInfo::GetCWasmEntry(
     NewFunctionArgs args = NewFunctionArgs::ForWasm(
         name, new_entry_code, isolate->sloppy_function_map());
     Handle<JSFunction> new_entry = isolate->factory()->NewFunction(args);
-    new_entry->set_context(
-        debug_info->wasm_instance()->compiled_module()->native_context());
+    new_entry->set_context(debug_info->wasm_instance()->native_context());
     new_entry->shared()->set_internal_formal_parameter_count(
         compiler::CWasmEntryParameters::kNumParameters);
     entries->set(index, *new_entry);

src/wasm/wasm-objects-inl.h

@@ -128,6 +128,7 @@ PRIMITIVE_ACCESSORS(WasmInstanceObject, indirect_function_table_targets,
 ACCESSORS(WasmInstanceObject, compiled_module, WasmCompiledModule,
           kCompiledModuleOffset)
 ACCESSORS(WasmInstanceObject, exports_object, JSObject, kExportsObjectOffset)
+ACCESSORS(WasmInstanceObject, native_context, Context, kNativeContextOffset)
 OPTIONAL_ACCESSORS(WasmInstanceObject, memory_object, WasmMemoryObject,
                    kMemoryObjectOffset)
 ACCESSORS(WasmInstanceObject, globals_buffer, JSArrayBuffer,
@@ -219,7 +220,6 @@ OPTIONAL_ACCESSORS(WasmDebugInfo, c_wasm_entry_map, Managed<wasm::SignatureMap>,
 
 // WasmCompiledModule
 WCM_OBJECT(WasmSharedModuleData, shared, kSharedOffset)
-WCM_WEAK_LINK(Context, native_context, kNativeContextOffset)
 WCM_OBJECT(FixedArray, export_wrappers, kExportWrappersOffset)
 WCM_OBJECT(WasmCompiledModule, next_instance, kNextInstanceOffset)
 WCM_OBJECT(WasmCompiledModule, prev_instance, kPrevInstanceOffset)

src/wasm/wasm-objects.cc

@@ -777,6 +777,7 @@ Handle<WasmInstanceObject> WasmInstanceObject::New(
   instance->set_indirect_function_table_sig_ids(nullptr);
   instance->set_indirect_function_table_targets(nullptr);
   instance->set_compiled_module(*compiled_module);
+  instance->set_native_context(*isolate->native_context());
 
   return instance;
 }
@@ -1362,9 +1363,6 @@ Handle<WasmCompiledModule> WasmCompiledModule::New(
     wasm::ModuleEnv& env) {
   Handle<WasmCompiledModule> compiled_module = Handle<WasmCompiledModule>::cast(
       isolate->factory()->NewStruct(WASM_COMPILED_MODULE_TYPE, TENURED));
-  Handle<WeakCell> weak_native_context =
-      isolate->factory()->NewWeakCell(isolate->native_context());
-  compiled_module->set_weak_native_context(*weak_native_context);
   if (!export_wrappers.is_null()) {
     compiled_module->set_export_wrappers(*export_wrappers);
   }
@@ -1389,7 +1387,6 @@ Handle<WasmCompiledModule> WasmCompiledModule::Clone(
   Handle<WasmCompiledModule> ret = Handle<WasmCompiledModule>::cast(
       isolate->factory()->NewStruct(WASM_COMPILED_MODULE_TYPE, TENURED));
   ret->set_shared(module->shared());
-  ret->set_weak_native_context(module->weak_native_context());
   ret->set_export_wrappers(module->export_wrappers());
   ret->set_weak_wasm_module(module->weak_wasm_module());
   ret->set_weak_owning_instance(isolate->heap()->empty_weak_cell());

src/wasm/wasm-objects.h

@@ -262,6 +262,7 @@ class WasmInstanceObject : public JSObject {
 
   DECL_ACCESSORS(compiled_module, WasmCompiledModule)
   DECL_ACCESSORS(exports_object, JSObject)
+  DECL_ACCESSORS(native_context, Context)
   DECL_OPTIONAL_ACCESSORS(memory_object, WasmMemoryObject)
   DECL_OPTIONAL_ACCESSORS(globals_buffer, JSArrayBuffer)
   DECL_OPTIONAL_ACCESSORS(imported_mutable_globals_buffers, FixedArray)
@@ -286,6 +287,7 @@ class WasmInstanceObject : public JSObject {
 #define WASM_INSTANCE_OBJECT_FIELDS(V)                                  \
   V(kCompiledModuleOffset, kPointerSize)                                \
   V(kExportsObjectOffset, kPointerSize)                                 \
+  V(kNativeContextOffset, kPointerSize)                                 \
   V(kMemoryObjectOffset, kPointerSize)                                  \
   V(kGlobalsBufferOffset, kPointerSize)                                 \
   V(kImportedMutableGlobalsBuffersOffset, kPointerSize)                 \
@@ -492,7 +494,6 @@ class WasmCompiledModule : public Struct {
 // Layout description.
 #define WASM_COMPILED_MODULE_FIELDS(V)          \
   V(kSharedOffset, kPointerSize)                \
-  V(kNativeContextOffset, kPointerSize)         \
   V(kExportWrappersOffset, kPointerSize)        \
   V(kNextInstanceOffset, kPointerSize)          \
   V(kPrevInstanceOffset, kPointerSize)          \
@@ -530,7 +531,6 @@ class WasmCompiledModule : public Struct {
   // By default, instance values go to WasmInstanceObject, however, if
   // we embed the generated code with a value, then we track that value here.
   WCM_OBJECT(WasmSharedModuleData, shared)
-  WCM_WEAK_LINK(Context, native_context)
   WCM_OBJECT(FixedArray, export_wrappers)
   WCM_CONST_OBJECT(WasmCompiledModule, next_instance)
   WCM_CONST_OBJECT(WasmCompiledModule, prev_instance)