[wasm] WebAssembly.Memory object can be referenced by multiple Instance objects.

src/wasm/wasm-js.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/api-natives.h"
 #include "src/api.h"
 #include "src/asmjs/asm-js.h"
 #include "src/asmjs/asm-typer.h"
 #include "src/asmjs/asm-wasm-builder.h"
 #include "src/assert-scope.h"
@@ skipping 10 matching lines @@
 #include "src/wasm/wasm-module.h"
 #include "src/wasm/wasm-objects.h"
 #include "src/wasm/wasm-result.h"
 
 typedef uint8_t byte;
 
 using v8::internal::wasm::ErrorThrower;
 
 namespace v8 {
 
-enum WasmMemoryObjectData {
-  kWasmMemoryBuffer,
-  kWasmMemoryMaximum,
-  kWasmMemoryInstanceObject
-};
-
 namespace {
 i::Handle<i::String> v8_str(i::Isolate* isolate, const char* str) {
   return isolate->factory()->NewStringFromAsciiChecked(str);
 }
 Local<String> v8_str(Isolate* isolate, const char* str) {
   return Utils::ToLocal(v8_str(reinterpret_cast<i::Isolate*>(isolate), str));
 }
 
 struct RawBuffer {
   const byte* start;
@@ skipping 176 matching lines @@
   i::Handle<i::JSArrayBuffer> memory = i::Handle<i::JSArrayBuffer>::null();
   if (args.Length() > 2 && args[2]->IsObject()) {
     Local<Object> obj = Local<Object>::Cast(args[2]);
     i::Handle<i::Object> mem_obj = v8::Utils::OpenHandle(*obj);
     if (i::WasmJs::IsWasmMemoryObject(i_isolate, mem_obj)) {
       memory = i::Handle<i::JSArrayBuffer>(
           i::Handle<i::WasmMemoryObject>::cast(mem_obj)->get_buffer(),
           i_isolate);
     } else {
       thrower.TypeError("Argument 2 must be a WebAssembly.Memory");
+      return;
     }
   }
   i::MaybeHandle<i::JSObject> instance =
       i::wasm::WasmModule::Instantiate(i_isolate, &thrower, i_obj, ffi, memory);
   if (instance.is_null()) {
     if (!thrower.error()) thrower.RuntimeError("Could not instantiate module");
     return;
   }
   DCHECK(!i_isolate->has_pending_exception());
   v8::ReturnValue<v8::Value> return_value = args.GetReturnValue();
@@ skipping 283 matching lines @@
   }
   if (args.Length() < 1) {
     v8::Local<v8::Value> e = v8::Exception::TypeError(
         v8_str(isolate, "Argument 0 required, must be numeric value of pages"));
     isolate->ThrowException(e);
     return;
   }
 
   uint32_t delta = args[0]->Uint32Value(context).FromJust();
   i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
-  i::Handle<i::JSObject> receiver =
-      i::Handle<i::JSObject>::cast(Utils::OpenHandle(*args.This()));
-  i::Handle<i::Object> instance_object(
-      receiver->GetInternalField(kWasmMemoryInstanceObject), i_isolate);
-  i::Handle<i::WasmInstanceObject> instance(
-      i::Handle<i::WasmInstanceObject>::cast(instance_object));
-
-  // TODO(gdeepti) Implement growing memory when shared by different
-  // instances.
-  int32_t ret = internal::wasm::GrowInstanceMemory(i_isolate, instance, delta);
+  i::Handle<i::Object> receiver =
+      i::Handle<i::Object>::cast(Utils::OpenHandle(*args.This()));
+  int32_t ret = i::wasm::GrowWebAssemblyMemory(i_isolate, receiver, delta);
   if (ret == -1) {
     v8::Local<v8::Value> e = v8::Exception::Error(
         v8_str(isolate, "Unable to grow instance memory."));
     isolate->ThrowException(e);
     return;
   }
-  i::MaybeHandle<i::JSArrayBuffer> buffer =
-      internal::wasm::GetInstanceMemory(i_isolate, instance);
-  if (buffer.is_null()) {
-    v8::Local<v8::Value> e = v8::Exception::Error(
-        v8_str(isolate, "WebAssembly.Memory buffer object not set."));
-    isolate->ThrowException(e);
-    return;
-  }
-  receiver->SetInternalField(kWasmMemoryBuffer, *buffer.ToHandleChecked());
   v8::ReturnValue<v8::Value> return_value = args.GetReturnValue();
   return_value.Set(ret);
 }
 
 void WebAssemblyMemoryGetBuffer(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
   v8::Isolate* isolate = args.GetIsolate();
   Local<Context> context = isolate->GetCurrentContext();
   i::Handle<i::Context> i_context = Utils::OpenHandle(*context);
   if (!BrandCheck(isolate, Utils::OpenHandle(*args.This()),
                   i::Handle<i::Symbol>(i_context->wasm_memory_sym()),
                   "Receiver is not a WebAssembly.Memory")) {
     return;
   }
   i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
-  i::Handle<i::JSObject> receiver =
-      i::Handle<i::JSObject>::cast(Utils::OpenHandle(*args.This()));
-  i::Handle<i::Object> buffer(receiver->GetInternalField(kWasmMemoryBuffer),
-                              i_isolate);
+  i::Handle<i::WasmMemoryObject> receiver =
+      i::Handle<i::WasmMemoryObject>::cast(Utils::OpenHandle(*args.This()));
+  i::Handle<i::Object> buffer(receiver->get_buffer(), i_isolate);
   DCHECK(buffer->IsJSArrayBuffer());
   v8::ReturnValue<v8::Value> return_value = args.GetReturnValue();
   return_value.Set(Utils::ToLocal(buffer));
 }
 }  // namespace
 
 // TODO(titzer): we use the API to create the function template because the
 // internal guts are too ugly to replicate here.
 static i::Handle<i::FunctionTemplateInfo> NewTemplate(i::Isolate* i_isolate,
                                                       FunctionCallback func) {
@@ skipping 193 matching lines @@
   i::Handle<i::Symbol> symbol(isolate->context()->wasm_memory_sym(), isolate);
   return HasBrand(value, symbol);
 }
 
 bool WasmJs::IsWasmTableObject(Isolate* isolate, Handle<Object> value) {
   i::Handle<i::Symbol> symbol(isolate->context()->wasm_table_sym(), isolate);
   return HasBrand(value, symbol);
 }
 }  // namespace internal
 }  // namespace v8