[wasm] Implement {Compile,Runtime}Error; fix traps from start function

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 39 matching lines @@
 
   if (source->IsArrayBuffer()) {
     // A raw array buffer was passed.
     Local<ArrayBuffer> buffer = Local<ArrayBuffer>::Cast(source);
     ArrayBuffer::Contents contents = buffer->GetContents();
 
     start = reinterpret_cast<const byte*>(contents.Data());
     end = start + contents.ByteLength();
 
     if (start == nullptr || end == start) {
-      thrower->Error("ArrayBuffer argument is empty");
+      thrower->CompileError("ArrayBuffer argument is empty");
     }
   } else if (source->IsTypedArray()) {
     // A TypedArray was passed.
     Local<TypedArray> array = Local<TypedArray>::Cast(source);
     Local<ArrayBuffer> buffer = array->Buffer();
 
     ArrayBuffer::Contents contents = buffer->GetContents();
 
     start =
         reinterpret_cast<const byte*>(contents.Data()) + array->ByteOffset();
     end = start + array->ByteLength();
 
     if (start == nullptr || end == start) {
-      thrower->Error("ArrayBuffer argument is empty");
+      thrower->TypeError("ArrayBuffer argument is empty");
     }
   } else {
-    thrower->Error("Argument 0 must be an ArrayBuffer or Uint8Array");
+    thrower->TypeError("Argument 0 must be an ArrayBuffer or Uint8Array");
   }
 
   return {start, end};
 }
 
 void VerifyModule(const v8::FunctionCallbackInfo<v8::Value>& args) {
   HandleScope scope(args.GetIsolate());
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(args.GetIsolate());
   ErrorThrower thrower(isolate, "Wasm.verifyModule()");
 
   if (args.Length() < 1) {
     thrower.TypeError("Argument 0 must be a buffer source");
     return;
   }
   RawBuffer buffer = GetRawBufferSource(args[0], &thrower);
   if (thrower.error()) return;
 
   i::Zone zone(isolate->allocator());
   internal::wasm::ModuleResult result =
       internal::wasm::DecodeWasmModule(isolate, &zone, buffer.start, buffer.end,
                                        true, internal::wasm::kWasmOrigin);
 
   if (result.failed()) {
-    thrower.Failed("", result);
+    thrower.CompileFailed("", result);
   }
 
   if (result.val) delete result.val;
 }
 
 void VerifyFunction(const v8::FunctionCallbackInfo<v8::Value>& args) {
   HandleScope scope(args.GetIsolate());
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(args.GetIsolate());
   ErrorThrower thrower(isolate, "Wasm.verifyFunction()");
 
   if (args.Length() < 1) {
     thrower.TypeError("Argument 0 must be a buffer source");
     return;
   }
   RawBuffer buffer = GetRawBufferSource(args[0], &thrower);
   if (thrower.error()) return;
 
   internal::wasm::FunctionResult result;
   {
     // Verification of a single function shouldn't allocate.
     i::DisallowHeapAllocation no_allocation;
     i::Zone zone(isolate->allocator());
     result = internal::wasm::DecodeWasmFunction(isolate, &zone, nullptr,
                                                 buffer.start, buffer.end);
   }
 
   if (result.failed()) {
-    thrower.Failed("", result);
+    thrower.CompileFailed("", result);
   }
 
   if (result.val) delete result.val;
 }
 
 i::MaybeHandle<i::JSObject> InstantiateModule(
     const v8::FunctionCallbackInfo<v8::Value>& args, const byte* start,
     const byte* end, ErrorThrower* thrower) {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(args.GetIsolate());
 
@@ skipping 187 matching lines @@
 
   i::Handle<i::JSArrayBuffer> memory = i::Handle<i::JSArrayBuffer>::null();
   if (args.Length() > 2 && args[2]->IsArrayBuffer()) {
     Local<Object> obj = Local<Object>::Cast(args[2]);
     i::Handle<i::Object> mem_obj = v8::Utils::OpenHandle(*obj);
     memory = i::Handle<i::JSArrayBuffer>(i::JSArrayBuffer::cast(*mem_obj));
   }
   i::MaybeHandle<i::JSObject> instance = i::wasm::WasmModule::Instantiate(
       i_isolate, &thrower, module_obj, ffi, memory);
   if (instance.is_null()) {
-    if (!thrower.error()) thrower.Error("Could not instantiate module");
+    if (!thrower.error()) thrower.RuntimeError("Could not instantiate module");
     return;
   }
+  DCHECK(!i_isolate->has_pending_exception());
   v8::ReturnValue<v8::Value> return_value = args.GetReturnValue();
   return_value.Set(Utils::ToLocal(instance.ToHandleChecked()));
 }
 
 bool GetIntegerProperty(v8::Isolate* isolate, ErrorThrower* thrower,
                         Local<Context> context, Local<v8::Object> object,
                         Local<String> property, int* result, int lower_bound,
                         int upper_bound) {
   v8::MaybeLocal<v8::Value> maybe = object->Get(context, property);
   v8::Local<v8::Value> value;
@@ skipping 87 matching lines @@
   v8::ReturnValue<v8::Value> return_value = args.GetReturnValue();
   return_value.Set(Utils::ToLocal(table_obj));
 }
 
 void WebAssemblyMemory(const v8::FunctionCallbackInfo<v8::Value>& args) {
   v8::Isolate* isolate = args.GetIsolate();
   HandleScope scope(isolate);
   ErrorThrower thrower(reinterpret_cast<i::Isolate*>(isolate),
                        "WebAssembly.Module()");
   if (args.Length() < 1 || !args[0]->IsObject()) {
-    thrower.TypeError("Argument 0 must be a table descriptor");
+    thrower.TypeError("Argument 0 must be a memory descriptor");
     return;
   }
   Local<Context> context = isolate->GetCurrentContext();
   Local<v8::Object> descriptor = args[0]->ToObject(context).ToLocalChecked();
   // The descriptor's 'initial'.
   int initial;
   if (!GetIntegerProperty(isolate, &thrower, context, descriptor,
                           v8_str(isolate, "initial"), &initial, 0, 65536)) {
     return;
   }
@@ skipping 199 matching lines @@
   context->set_wasm_memory_constructor(*memory_constructor);
   Handle<JSObject> memory_proto =
       factory->NewJSObject(memory_constructor, TENURED);
   map = isolate->factory()->NewMap(
       i::JS_OBJECT_TYPE, i::JSObject::kHeaderSize + 2 * i::kPointerSize);
   JSFunction::SetInitialMap(memory_constructor, map, memory_proto);
   JSObject::AddProperty(memory_proto, isolate->factory()->constructor_string(),
                         memory_constructor, DONT_ENUM);
   InstallFunc(isolate, memory_proto, "grow", WebAssemblyMemoryGrow);
   InstallGetter(isolate, memory_proto, "buffer", WebAssemblyMemoryGetBuffer);
+
+  // Setup errors
+  attributes = static_cast<PropertyAttributes>(DONT_DELETE | READ_ONLY);
+  Handle<JSFunction> compile_error(
+      isolate->native_context()->wasm_compile_error_function());
+  JSObject::AddProperty(wasm_object, isolate->factory()->CompileError_string(),
+                        compile_error, attributes);
+  Handle<JSFunction> runtime_error(
+      isolate->native_context()->wasm_runtime_error_function());
+  JSObject::AddProperty(wasm_object, isolate->factory()->RuntimeError_string(),
+                        runtime_error, attributes);
 }
 
 void WasmJs::Install(Isolate* isolate, Handle<JSGlobalObject> global) {
   if (!FLAG_expose_wasm && !FLAG_validate_asm) {
     return;
   }
 
   Factory* factory = isolate->factory();
 
   // Setup wasm function map.
@@ skipping 77 matching lines @@
 Handle<JSArrayBuffer> WasmJs::GetWasmMemoryArrayBuffer(Isolate* isolate,
                                                        Handle<Object> value) {
   DCHECK(IsWasmMemoryObject(isolate, value));
   Handle<Object> buf(
       JSObject::cast(*value)->GetInternalField(kWasmMemoryBufferFieldIndex),
       isolate);
   return Handle<JSArrayBuffer>::cast(buf);
 }
 }  // namespace internal
 }  // namespace v8