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1091 lines (988 loc) · 43 KB
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// Copyright 2021 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/debug/debug-wasm-objects.h"
#include "src/api/api-inl.h"
#include "src/api/api-natives.h"
#include "src/base/strings.h"
#include "src/debug/debug-wasm-objects-inl.h"
#include "src/execution/frames-inl.h"
#include "src/objects/property-descriptor.h"
#include "src/wasm/names-provider.h"
#include "src/wasm/string-builder.h"
#include "src/wasm/wasm-debug.h"
#include "src/wasm/wasm-objects-inl.h"
#include "src/wasm/wasm-value.h"
namespace v8 {
namespace internal {
namespace {
using StringBuilder = wasm::StringBuilder;
Handle<String> ToInternalString(StringBuilder& sb, Isolate* isolate) {
return isolate->factory()->InternalizeString(
base::VectorOf(sb.start(), sb.length()));
}
enum DebugProxyId {
kFunctionsProxy,
kGlobalsProxy,
kMemoriesProxy,
kTablesProxy,
kLastInstanceProxyId = kTablesProxy,
kContextProxy,
kLocalsProxy,
kStackProxy,
kStructProxy,
kArrayProxy,
kLastProxyId = kArrayProxy,
kNumProxies = kLastProxyId + 1,
kNumInstanceProxies = kLastInstanceProxyId + 1
};
constexpr int kWasmValueMapIndex = kNumProxies;
constexpr int kNumDebugMaps = kWasmValueMapIndex + 1;
Handle<FixedArray> GetOrCreateDebugMaps(Isolate* isolate) {
Handle<FixedArray> maps = isolate->wasm_debug_maps();
if (maps->length() == 0) {
maps = isolate->factory()->NewFixedArrayWithHoles(kNumDebugMaps);
isolate->native_context()->set_wasm_debug_maps(*maps);
}
return maps;
}
// Creates a Map for the given debug proxy |id| using the |create_template_fn|
// on-demand and caches this map in the global object. The map is derived from
// the FunctionTemplate returned by |create_template_fn| and has its prototype
// set to |null| and is marked non-extensible (by default).
// TODO(bmeurer): remove the extensibility opt-out and replace it with a proper
// way to add non-intercepted named properties.
Handle<Map> GetOrCreateDebugProxyMap(
Isolate* isolate, DebugProxyId id,
v8::Local<v8::FunctionTemplate> (*create_template_fn)(v8::Isolate*),
bool make_non_extensible = true) {
auto maps = GetOrCreateDebugMaps(isolate);
CHECK_LE(kNumProxies, maps->length());
if (!maps->is_the_hole(isolate, id)) {
return handle(Map::cast(maps->get(id)), isolate);
}
auto tmp = (*create_template_fn)(reinterpret_cast<v8::Isolate*>(isolate));
auto fun = ApiNatives::InstantiateFunction(isolate, Utils::OpenHandle(*tmp))
.ToHandleChecked();
auto map = JSFunction::GetDerivedMap(isolate, fun, fun).ToHandleChecked();
Map::SetPrototype(isolate, map, isolate->factory()->null_value());
if (make_non_extensible) {
map->set_is_extensible(false);
}
maps->set(id, *map);
return map;
}
// Base class for debug proxies, offers indexed access. The subclasses
// need to implement |Count| and |Get| methods appropriately.
template <typename T, DebugProxyId id, typename Provider>
struct IndexedDebugProxy {
static constexpr DebugProxyId kId = id;
static Handle<JSObject> Create(Isolate* isolate, Handle<Provider> provider,
bool make_map_non_extensible = true) {
auto object_map = GetOrCreateDebugProxyMap(isolate, kId, &T::CreateTemplate,
make_map_non_extensible);
auto object = isolate->factory()->NewJSObjectFromMap(object_map);
object->SetEmbedderField(kProviderField, *provider);
return object;
}
enum {
kProviderField,
kFieldCount,
};
static v8::Local<v8::FunctionTemplate> CreateTemplate(v8::Isolate* isolate) {
Local<v8::FunctionTemplate> templ = v8::FunctionTemplate::New(isolate);
templ->SetClassName(
v8::String::NewFromUtf8(isolate, T::kClassName).ToLocalChecked());
templ->InstanceTemplate()->SetInternalFieldCount(T::kFieldCount);
templ->InstanceTemplate()->SetHandler(
v8::IndexedPropertyHandlerConfiguration(
&T::IndexedGetter, {}, &T::IndexedQuery, {}, &T::IndexedEnumerator,
{}, &T::IndexedDescriptor, {},
v8::PropertyHandlerFlags::kHasNoSideEffect));
return templ;
}
template <typename V>
static Isolate* GetIsolate(const PropertyCallbackInfo<V>& info) {
return reinterpret_cast<Isolate*>(info.GetIsolate());
}
template <typename V>
static Handle<JSObject> GetHolder(const PropertyCallbackInfo<V>& info) {
return Handle<JSObject>::cast(Utils::OpenHandle(*info.Holder()));
}
static Handle<Provider> GetProvider(Handle<JSObject> holder,
Isolate* isolate) {
return handle(Provider::cast(holder->GetEmbedderField(kProviderField)),
isolate);
}
template <typename V>
static Handle<Provider> GetProvider(const PropertyCallbackInfo<V>& info) {
return GetProvider(GetHolder(info), GetIsolate(info));
}
static void IndexedGetter(uint32_t index,
const PropertyCallbackInfo<v8::Value>& info) {
auto isolate = GetIsolate(info);
auto provider = GetProvider(info);
if (index < T::Count(isolate, provider)) {
auto value = T::Get(isolate, provider, index);
info.GetReturnValue().Set(Utils::ToLocal(value));
}
}
static void IndexedDescriptor(uint32_t index,
const PropertyCallbackInfo<v8::Value>& info) {
auto isolate = GetIsolate(info);
auto provider = GetProvider(info);
if (index < T::Count(isolate, provider)) {
PropertyDescriptor descriptor;
descriptor.set_configurable(false);
descriptor.set_enumerable(true);
descriptor.set_writable(false);
descriptor.set_value(T::Get(isolate, provider, index));
info.GetReturnValue().Set(Utils::ToLocal(descriptor.ToObject(isolate)));
}
}
static void IndexedQuery(uint32_t index,
const PropertyCallbackInfo<v8::Integer>& info) {
if (index < T::Count(GetIsolate(info), GetProvider(info))) {
info.GetReturnValue().Set(Integer::New(
info.GetIsolate(),
PropertyAttribute::DontDelete | PropertyAttribute::ReadOnly));
}
}
static void IndexedEnumerator(const PropertyCallbackInfo<v8::Array>& info) {
auto isolate = GetIsolate(info);
auto count = T::Count(isolate, GetProvider(info));
auto indices = isolate->factory()->NewFixedArray(count);
for (uint32_t index = 0; index < count; ++index) {
indices->set(index, Smi::FromInt(index));
}
info.GetReturnValue().Set(
Utils::ToLocal(isolate->factory()->NewJSArrayWithElements(
indices, PACKED_SMI_ELEMENTS)));
}
};
// Extends |IndexedDebugProxy| with named access, where the names are computed
// on-demand, and all names are assumed to start with a dollar char ($). This
// is important in order to scale to Wasm modules with hundreds of thousands
// of functions in them.
template <typename T, DebugProxyId id, typename Provider = WasmInstanceObject>
struct NamedDebugProxy : IndexedDebugProxy<T, id, Provider> {
static v8::Local<v8::FunctionTemplate> CreateTemplate(v8::Isolate* isolate) {
auto templ = IndexedDebugProxy<T, id, Provider>::CreateTemplate(isolate);
templ->InstanceTemplate()->SetHandler(v8::NamedPropertyHandlerConfiguration(
&T::NamedGetter, {}, &T::NamedQuery, {}, &T::NamedEnumerator, {},
&T::NamedDescriptor, {}, v8::PropertyHandlerFlags::kHasNoSideEffect));
return templ;
}
static void IndexedEnumerator(const PropertyCallbackInfo<v8::Array>& info) {
info.GetReturnValue().Set(v8::Array::New(info.GetIsolate()));
}
static Handle<NameDictionary> GetNameTable(Handle<JSObject> holder,
Isolate* isolate) {
Handle<Symbol> symbol = isolate->factory()->wasm_debug_proxy_names_symbol();
Handle<Object> table_or_undefined =
JSObject::GetProperty(isolate, holder, symbol).ToHandleChecked();
if (!IsUndefined(*table_or_undefined, isolate)) {
return Handle<NameDictionary>::cast(table_or_undefined);
}
auto provider = T::GetProvider(holder, isolate);
auto count = T::Count(isolate, provider);
auto table = NameDictionary::New(isolate, count);
for (uint32_t index = 0; index < count; ++index) {
HandleScope scope(isolate);
auto key = T::GetName(isolate, provider, index);
if (table->FindEntry(isolate, key).is_found()) continue;
Handle<Smi> value(Smi::FromInt(index), isolate);
table = NameDictionary::Add(isolate, table, key, value,
PropertyDetails::Empty());
}
Object::SetProperty(isolate, holder, symbol, table).Check();
return table;
}
template <typename V>
static base::Optional<uint32_t> FindName(
Local<v8::Name> name, const PropertyCallbackInfo<V>& info) {
if (!name->IsString()) return {};
auto name_str = Utils::OpenHandle(*name.As<v8::String>());
if (name_str->length() == 0 || name_str->Get(0) != '$') return {};
auto isolate = T::GetIsolate(info);
auto table = GetNameTable(T::GetHolder(info), isolate);
auto entry = table->FindEntry(isolate, name_str);
if (entry.is_found()) return Smi::ToInt(table->ValueAt(entry));
return {};
}
static void NamedGetter(Local<v8::Name> name,
const PropertyCallbackInfo<v8::Value>& info) {
if (auto index = FindName(name, info)) T::IndexedGetter(*index, info);
}
static void NamedQuery(Local<v8::Name> name,
const PropertyCallbackInfo<v8::Integer>& info) {
if (auto index = FindName(name, info)) T::IndexedQuery(*index, info);
}
static void NamedDescriptor(Local<v8::Name> name,
const PropertyCallbackInfo<v8::Value>& info) {
if (auto index = FindName(name, info)) T::IndexedDescriptor(*index, info);
}
static void NamedEnumerator(const PropertyCallbackInfo<v8::Array>& info) {
auto isolate = T::GetIsolate(info);
auto table = GetNameTable(T::GetHolder(info), isolate);
auto names = NameDictionary::IterationIndices(isolate, table);
for (int i = 0; i < names->length(); ++i) {
InternalIndex entry(Smi::ToInt(names->get(i)));
names->set(i, table->NameAt(entry));
}
info.GetReturnValue().Set(Utils::ToLocal(
isolate->factory()->NewJSArrayWithElements(names, PACKED_ELEMENTS)));
}
};
// This class implements the "functions" proxy.
struct FunctionsProxy : NamedDebugProxy<FunctionsProxy, kFunctionsProxy> {
static constexpr char const* kClassName = "Functions";
static uint32_t Count(Isolate* isolate, Handle<WasmInstanceObject> instance) {
return static_cast<uint32_t>(instance->module()->functions.size());
}
static Handle<Object> Get(Isolate* isolate,
Handle<WasmInstanceObject> instance,
uint32_t index) {
Handle<WasmInternalFunction> internal =
WasmInstanceObject::GetOrCreateWasmInternalFunction(isolate, instance,
index);
return WasmInternalFunction::GetOrCreateExternal(internal);
}
static Handle<String> GetName(Isolate* isolate,
Handle<WasmInstanceObject> instance,
uint32_t index) {
return GetWasmFunctionDebugName(isolate, instance, index);
}
};
// This class implements the "globals" proxy.
struct GlobalsProxy : NamedDebugProxy<GlobalsProxy, kGlobalsProxy> {
static constexpr char const* kClassName = "Globals";
static uint32_t Count(Isolate* isolate, Handle<WasmInstanceObject> instance) {
return static_cast<uint32_t>(instance->module()->globals.size());
}
static Handle<Object> Get(Isolate* isolate,
Handle<WasmInstanceObject> instance,
uint32_t index) {
Handle<WasmModuleObject> module(instance->module_object(), isolate);
return WasmValueObject::New(
isolate,
WasmInstanceObject::GetGlobalValue(instance,
instance->module()->globals[index]),
module);
}
static Handle<String> GetName(Isolate* isolate,
Handle<WasmInstanceObject> instance,
uint32_t index) {
wasm::NamesProvider* names =
instance->module_object()->native_module()->GetNamesProvider();
StringBuilder sb;
names->PrintGlobalName(sb, index);
return ToInternalString(sb, isolate);
}
};
// This class implements the "memories" proxy.
struct MemoriesProxy : NamedDebugProxy<MemoriesProxy, kMemoriesProxy> {
static constexpr char const* kClassName = "Memories";
static uint32_t Count(Isolate* isolate, Handle<WasmInstanceObject> instance) {
return instance->memory_objects()->length();
}
static Handle<Object> Get(Isolate* isolate,
Handle<WasmInstanceObject> instance,
uint32_t index) {
return handle(instance->memory_object(index), isolate);
}
static Handle<String> GetName(Isolate* isolate,
Handle<WasmInstanceObject> instance,
uint32_t index) {
wasm::NamesProvider* names =
instance->module_object()->native_module()->GetNamesProvider();
StringBuilder sb;
names->PrintMemoryName(sb, index);
return ToInternalString(sb, isolate);
}
};
// This class implements the "tables" proxy.
struct TablesProxy : NamedDebugProxy<TablesProxy, kTablesProxy> {
static constexpr char const* kClassName = "Tables";
static uint32_t Count(Isolate* isolate, Handle<WasmInstanceObject> instance) {
return instance->tables()->length();
}
static Handle<Object> Get(Isolate* isolate,
Handle<WasmInstanceObject> instance,
uint32_t index) {
return handle(instance->tables()->get(index), isolate);
}
static Handle<String> GetName(Isolate* isolate,
Handle<WasmInstanceObject> instance,
uint32_t index) {
wasm::NamesProvider* names =
instance->module_object()->native_module()->GetNamesProvider();
StringBuilder sb;
names->PrintTableName(sb, index);
return ToInternalString(sb, isolate);
}
};
// This class implements the "locals" proxy.
struct LocalsProxy : NamedDebugProxy<LocalsProxy, kLocalsProxy, FixedArray> {
static constexpr char const* kClassName = "Locals";
static Handle<JSObject> Create(WasmFrame* frame) {
auto isolate = frame->isolate();
auto debug_info = frame->native_module()->GetDebugInfo();
// TODO(bmeurer): Check if pc is inspectable.
int count = debug_info->GetNumLocals(frame->pc());
auto function = debug_info->GetFunctionAtAddress(frame->pc());
auto values = isolate->factory()->NewFixedArray(count + 2);
Handle<WasmModuleObject> module_object(
frame->wasm_instance()->module_object(), isolate);
for (int i = 0; i < count; ++i) {
auto value = WasmValueObject::New(
isolate,
debug_info->GetLocalValue(i, frame->pc(), frame->fp(),
frame->callee_fp(), isolate),
module_object);
values->set(i, *value);
}
values->set(count + 0, frame->wasm_instance()->module_object());
values->set(count + 1, Smi::FromInt(function.func_index));
return NamedDebugProxy::Create(isolate, values);
}
static uint32_t Count(Isolate* isolate, Handle<FixedArray> values) {
return values->length() - 2;
}
static Handle<Object> Get(Isolate* isolate, Handle<FixedArray> values,
uint32_t index) {
return handle(values->get(index), isolate);
}
static Handle<String> GetName(Isolate* isolate, Handle<FixedArray> values,
uint32_t index) {
uint32_t count = Count(isolate, values);
auto native_module =
WasmModuleObject::cast(values->get(count + 0))->native_module();
auto function_index = Smi::ToInt(Smi::cast(values->get(count + 1)));
wasm::NamesProvider* names = native_module->GetNamesProvider();
StringBuilder sb;
names->PrintLocalName(sb, function_index, index);
return ToInternalString(sb, isolate);
}
};
// This class implements the "stack" proxy (which offers only indexed access).
struct StackProxy : IndexedDebugProxy<StackProxy, kStackProxy, FixedArray> {
static constexpr char const* kClassName = "Stack";
static Handle<JSObject> Create(WasmFrame* frame) {
auto isolate = frame->isolate();
auto debug_info = frame->wasm_instance()
->module_object()
->native_module()
->GetDebugInfo();
int count = debug_info->GetStackDepth(frame->pc());
auto values = isolate->factory()->NewFixedArray(count);
Handle<WasmModuleObject> module_object(
frame->wasm_instance()->module_object(), isolate);
for (int i = 0; i < count; ++i) {
auto value = WasmValueObject::New(
isolate,
debug_info->GetStackValue(i, frame->pc(), frame->fp(),
frame->callee_fp(), isolate),
module_object);
values->set(i, *value);
}
return IndexedDebugProxy::Create(isolate, values);
}
static uint32_t Count(Isolate* isolate, Handle<FixedArray> values) {
return values->length();
}
static Handle<Object> Get(Isolate* isolate, Handle<FixedArray> values,
uint32_t index) {
return handle(values->get(index), isolate);
}
};
// Creates FixedArray with size |kNumInstanceProxies| as cache on-demand
// on the |instance|, stored under the |wasm_debug_proxy_cache_symbol|.
// This is used to cache the various instance debug proxies (functions,
// globals, tables, and memories) on the WasmInstanceObject.
Handle<FixedArray> GetOrCreateInstanceProxyCache(
Isolate* isolate, Handle<WasmInstanceObject> instance) {
Handle<Object> cache;
Handle<Symbol> symbol = isolate->factory()->wasm_debug_proxy_cache_symbol();
if (!Object::GetProperty(isolate, instance, symbol).ToHandle(&cache) ||
IsUndefined(*cache, isolate)) {
cache = isolate->factory()->NewFixedArrayWithHoles(kNumInstanceProxies);
Object::SetProperty(isolate, instance, symbol, cache).Check();
}
return Handle<FixedArray>::cast(cache);
}
// Creates an instance of the |Proxy| on-demand and caches that on the
// |instance|.
template <typename Proxy>
Handle<JSObject> GetOrCreateInstanceProxy(Isolate* isolate,
Handle<WasmInstanceObject> instance) {
static_assert(Proxy::kId < kNumInstanceProxies);
Handle<FixedArray> proxies = GetOrCreateInstanceProxyCache(isolate, instance);
if (!proxies->is_the_hole(isolate, Proxy::kId)) {
return handle(JSObject::cast(proxies->get(Proxy::kId)), isolate);
}
Handle<JSObject> proxy = Proxy::Create(isolate, instance);
proxies->set(Proxy::kId, *proxy);
return proxy;
}
// This class implements the debug proxy for a given Wasm frame. The debug
// proxy is used when evaluating JavaScript expressions on a wasm frame via
// the inspector |Runtime.evaluateOnCallFrame()| API and enables developers
// and extensions to inspect the WebAssembly engine state from JavaScript.
// The proxy provides the following interface:
//
// type WasmValue = {
// type: string;
// value: number | bigint | object | string;
// };
// type WasmFunction = (... args : WasmValue[]) = > WasmValue;
// interface WasmInterface {
// $globalX: WasmValue;
// $varX: WasmValue;
// $funcX(a : WasmValue /*, ...*/) : WasmValue;
// readonly $memoryX : WebAssembly.Memory;
// readonly $tableX : WebAssembly.Table;
//
// readonly instance : WebAssembly.Instance;
// readonly module : WebAssembly.Module;
//
// readonly memories : {[nameOrIndex:string | number] : WebAssembly.Memory};
// readonly tables : {[nameOrIndex:string | number] : WebAssembly.Table};
// readonly stack : WasmValue[];
// readonly globals : {[nameOrIndex:string | number] : WasmValue};
// readonly locals : {[nameOrIndex:string | number] : WasmValue};
// readonly functions : {[nameOrIndex:string | number] : WasmFunction};
// }
//
// The wasm index spaces memories, tables, stack, globals, locals, and
// functions are JSObjects with interceptors that lazily produce values
// either by index or by name (except for stack).
// Only the names are reported by APIs such as Object.keys() and
// Object.getOwnPropertyNames(), since the indices are not meant to be
// used interactively by developers (in Chrome DevTools), but are provided
// for WebAssembly language extensions. Also note that these JSObjects
// all have null prototypes, to not confuse context lookup and to make
// their purpose as dictionaries clear.
//
// See http://doc/1VZOJrU2VsqOZe3IUzbwQWQQSZwgGySsm5119Ust1gUA and
// http://bit.ly/devtools-wasm-entities for more details.
class ContextProxyPrototype {
public:
static Handle<JSObject> Create(Isolate* isolate) {
auto object_map =
GetOrCreateDebugProxyMap(isolate, kContextProxy, &CreateTemplate);
return isolate->factory()->NewJSObjectFromMap(object_map);
}
private:
static v8::Local<v8::FunctionTemplate> CreateTemplate(v8::Isolate* isolate) {
Local<v8::FunctionTemplate> templ = v8::FunctionTemplate::New(isolate);
templ->InstanceTemplate()->SetHandler(v8::NamedPropertyHandlerConfiguration(
&NamedGetter, {}, {}, {}, {}, {}, {}, {},
static_cast<v8::PropertyHandlerFlags>(
static_cast<unsigned>(
v8::PropertyHandlerFlags::kOnlyInterceptStrings) |
static_cast<unsigned>(
v8::PropertyHandlerFlags::kHasNoSideEffect))));
return templ;
}
static MaybeHandle<Object> GetNamedProperty(Isolate* isolate,
Handle<JSObject> receiver,
Handle<String> name) {
if (name->length() != 0 && name->Get(0) == '$') {
const char* kDelegateNames[] = {"memories", "locals", "tables",
"functions", "globals"};
for (auto delegate_name : kDelegateNames) {
Handle<Object> delegate;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, delegate,
JSObject::GetProperty(isolate, receiver, delegate_name), Object);
if (!IsUndefined(*delegate, isolate)) {
Handle<Object> value;
ASSIGN_RETURN_ON_EXCEPTION(
isolate, value, Object::GetProperty(isolate, delegate, name),
Object);
if (!IsUndefined(*value, isolate)) return value;
}
}
}
return {};
}
static void NamedGetter(Local<v8::Name> name,
const PropertyCallbackInfo<v8::Value>& info) {
auto name_string = Handle<String>::cast(Utils::OpenHandle(*name));
auto isolate = reinterpret_cast<Isolate*>(info.GetIsolate());
auto receiver = Handle<JSObject>::cast(Utils::OpenHandle(*info.This()));
Handle<Object> value;
if (GetNamedProperty(isolate, receiver, name_string).ToHandle(&value)) {
info.GetReturnValue().Set(Utils::ToLocal(value));
}
}
};
class ContextProxy {
public:
static Handle<JSObject> Create(WasmFrame* frame) {
Isolate* isolate = frame->isolate();
auto object = isolate->factory()->NewSlowJSObjectWithNullProto();
Handle<WasmInstanceObject> instance(frame->wasm_instance(), isolate);
JSObject::AddProperty(isolate, object, "instance", instance, FROZEN);
Handle<WasmModuleObject> module_object(instance->module_object(), isolate);
JSObject::AddProperty(isolate, object, "module", module_object, FROZEN);
auto locals = LocalsProxy::Create(frame);
JSObject::AddProperty(isolate, object, "locals", locals, FROZEN);
auto stack = StackProxy::Create(frame);
JSObject::AddProperty(isolate, object, "stack", stack, FROZEN);
auto memories = GetOrCreateInstanceProxy<MemoriesProxy>(isolate, instance);
JSObject::AddProperty(isolate, object, "memories", memories, FROZEN);
auto tables = GetOrCreateInstanceProxy<TablesProxy>(isolate, instance);
JSObject::AddProperty(isolate, object, "tables", tables, FROZEN);
auto globals = GetOrCreateInstanceProxy<GlobalsProxy>(isolate, instance);
JSObject::AddProperty(isolate, object, "globals", globals, FROZEN);
auto functions =
GetOrCreateInstanceProxy<FunctionsProxy>(isolate, instance);
JSObject::AddProperty(isolate, object, "functions", functions, FROZEN);
Handle<JSObject> prototype = ContextProxyPrototype::Create(isolate);
JSObject::SetPrototype(isolate, object, prototype, false, kDontThrow)
.Check();
return object;
}
};
class DebugWasmScopeIterator final : public debug::ScopeIterator {
public:
explicit DebugWasmScopeIterator(WasmFrame* frame)
: frame_(frame),
type_(debug::ScopeIterator::ScopeTypeWasmExpressionStack) {
// Skip local scope and expression stack scope if the frame is not
// inspectable.
if (!frame->is_inspectable()) {
type_ = debug::ScopeIterator::ScopeTypeModule;
}
}
bool Done() override { return type_ == ScopeTypeWith; }
void Advance() override {
DCHECK(!Done());
switch (type_) {
case ScopeTypeWasmExpressionStack:
type_ = debug::ScopeIterator::ScopeTypeLocal;
break;
case ScopeTypeLocal:
type_ = debug::ScopeIterator::ScopeTypeModule;
break;
case ScopeTypeModule:
// We use ScopeTypeWith type as marker for done.
type_ = debug::ScopeIterator::ScopeTypeWith;
break;
default:
UNREACHABLE();
}
}
ScopeType GetType() override { return type_; }
v8::Local<v8::Object> GetObject() override {
Isolate* isolate = frame_->isolate();
switch (type_) {
case debug::ScopeIterator::ScopeTypeModule: {
Handle<WasmInstanceObject> instance(frame_->wasm_instance(), isolate);
Handle<JSObject> object =
isolate->factory()->NewSlowJSObjectWithNullProto();
JSObject::AddProperty(isolate, object, "instance", instance, FROZEN);
Handle<JSObject> module_object(instance->module_object(), isolate);
JSObject::AddProperty(isolate, object, "module", module_object, FROZEN);
if (FunctionsProxy::Count(isolate, instance) != 0) {
JSObject::AddProperty(
isolate, object, "functions",
GetOrCreateInstanceProxy<FunctionsProxy>(isolate, instance),
FROZEN);
}
if (GlobalsProxy::Count(isolate, instance) != 0) {
JSObject::AddProperty(
isolate, object, "globals",
GetOrCreateInstanceProxy<GlobalsProxy>(isolate, instance),
FROZEN);
}
if (MemoriesProxy::Count(isolate, instance) != 0) {
JSObject::AddProperty(
isolate, object, "memories",
GetOrCreateInstanceProxy<MemoriesProxy>(isolate, instance),
FROZEN);
}
if (TablesProxy::Count(isolate, instance) != 0) {
JSObject::AddProperty(
isolate, object, "tables",
GetOrCreateInstanceProxy<TablesProxy>(isolate, instance), FROZEN);
}
return Utils::ToLocal(object);
}
case debug::ScopeIterator::ScopeTypeLocal: {
return Utils::ToLocal(LocalsProxy::Create(frame_));
}
case debug::ScopeIterator::ScopeTypeWasmExpressionStack: {
auto object = isolate->factory()->NewSlowJSObjectWithNullProto();
auto stack = StackProxy::Create(frame_);
JSObject::AddProperty(isolate, object, "stack", stack, FROZEN);
return Utils::ToLocal(object);
}
default:
UNREACHABLE();
}
}
v8::Local<v8::Value> GetFunctionDebugName() override {
return Utils::ToLocal(frame_->isolate()->factory()->empty_string());
}
int GetScriptId() override { return -1; }
bool HasLocationInfo() override { return false; }
debug::Location GetStartLocation() override { return {}; }
debug::Location GetEndLocation() override { return {}; }
bool SetVariableValue(v8::Local<v8::String> name,
v8::Local<v8::Value> value) override {
return false;
}
private:
WasmFrame* const frame_;
ScopeType type_;
};
Handle<String> WasmSimd128ToString(Isolate* isolate, wasm::Simd128 s128) {
// We use the canonical format as described in:
// https://github.com/WebAssembly/simd/blob/master/proposals/simd/TextSIMD.md
base::EmbeddedVector<char, 50> buffer;
auto i32x4 = s128.to_i32x4();
SNPrintF(buffer, "i32x4 0x%08X 0x%08X 0x%08X 0x%08X", i32x4.val[0],
i32x4.val[1], i32x4.val[2], i32x4.val[3]);
return isolate->factory()->NewStringFromAsciiChecked(buffer.data());
}
Handle<String> GetRefTypeName(Isolate* isolate, wasm::ValueType type,
wasm::NativeModule* module) {
DCHECK(type.is_object_reference());
StringBuilder name;
module->GetNamesProvider()->PrintValueType(name, type);
return ToInternalString(name, isolate);
}
// Returns the type name for the given value. Uses the module object for
// providing user-defined type names if available, otherwise falls back
// to numbers for indexed types.
Handle<String> GetRefTypeName(Isolate* isolate, wasm::ValueType type,
Handle<WasmModuleObject> module_object) {
if (!module_object.is_null()) {
return GetRefTypeName(isolate, type, module_object->native_module());
}
std::string name = type.name();
return isolate->factory()->InternalizeString({name.data(), name.length()});
}
} // namespace
// static
Handle<WasmValueObject> WasmValueObject::New(Isolate* isolate,
Handle<String> type,
Handle<Object> value) {
auto maps = GetOrCreateDebugMaps(isolate);
if (maps->is_the_hole(isolate, kWasmValueMapIndex)) {
Handle<Map> map = isolate->factory()->NewMap(
WASM_VALUE_OBJECT_TYPE, WasmValueObject::kSize,
TERMINAL_FAST_ELEMENTS_KIND, 2);
Map::EnsureDescriptorSlack(isolate, map, 2);
map->SetConstructor(*isolate->object_function());
{ // type
Descriptor d = Descriptor::DataField(
isolate,
isolate->factory()->InternalizeString(base::StaticCharVector("type")),
WasmValueObject::kTypeIndex, FROZEN, Representation::Tagged());
map->AppendDescriptor(isolate, &d);
}
{ // value
Descriptor d = Descriptor::DataField(
isolate,
isolate->factory()->InternalizeString(
base::StaticCharVector("value")),
WasmValueObject::kValueIndex, FROZEN, Representation::Tagged());
map->AppendDescriptor(isolate, &d);
}
map->set_is_extensible(false);
maps->set(kWasmValueMapIndex, *map);
}
Handle<Map> value_map =
handle(Map::cast(maps->get(kWasmValueMapIndex)), isolate);
Handle<WasmValueObject> object = Handle<WasmValueObject>::cast(
isolate->factory()->NewJSObjectFromMap(value_map));
object->set_type(*type);
object->set_value(*value);
return object;
}
// This class implements a proxy for a single inspectable Wasm struct.
struct StructProxy : NamedDebugProxy<StructProxy, kStructProxy, FixedArray> {
static constexpr char const* kClassName = "Struct";
static const int kObjectIndex = 0;
static const int kModuleIndex = 1;
static const int kTypeIndexIndex = 2;
static const int kLength = 3;
static Handle<JSObject> Create(Isolate* isolate, Handle<WasmStruct> value,
Handle<WasmModuleObject> module) {
Handle<FixedArray> data = isolate->factory()->NewFixedArray(kLength);
data->set(kObjectIndex, *value);
data->set(kModuleIndex, *module);
int struct_type_index = value->map()->wasm_type_info()->type_index();
data->set(kTypeIndexIndex, Smi::FromInt(struct_type_index));
return NamedDebugProxy::Create(isolate, data);
}
static uint32_t Count(Isolate* isolate, Handle<FixedArray> data) {
return WasmStruct::cast(data->get(kObjectIndex))->type()->field_count();
}
static Handle<Object> Get(Isolate* isolate, Handle<FixedArray> data,
uint32_t index) {
Handle<WasmStruct> obj(WasmStruct::cast(data->get(kObjectIndex)), isolate);
Handle<WasmModuleObject> module(
WasmModuleObject::cast(data->get(kModuleIndex)), isolate);
return WasmValueObject::New(isolate, obj->GetFieldValue(index), module);
}
static Handle<String> GetName(Isolate* isolate, Handle<FixedArray> data,
uint32_t index) {
wasm::NativeModule* native_module =
WasmModuleObject::cast(data->get(kModuleIndex))->native_module();
int struct_type_index = Smi::ToInt(Smi::cast(data->get(kTypeIndexIndex)));
wasm::NamesProvider* names = native_module->GetNamesProvider();
StringBuilder sb;
names->PrintFieldName(sb, struct_type_index, index);
return ToInternalString(sb, isolate);
}
};
// This class implements a proxy for a single inspectable Wasm array.
struct ArrayProxy : IndexedDebugProxy<ArrayProxy, kArrayProxy, FixedArray> {
static constexpr char const* kClassName = "Array";
static const int kObjectIndex = 0;
static const int kModuleIndex = 1;
static const int kLength = 2;
static Handle<JSObject> Create(Isolate* isolate, Handle<WasmArray> value,
Handle<WasmModuleObject> module) {
Handle<FixedArray> data = isolate->factory()->NewFixedArray(kLength);
data->set(kObjectIndex, *value);
data->set(kModuleIndex, *module);
Handle<JSObject> proxy = IndexedDebugProxy::Create(
isolate, data, false /* leave map extensible */);
uint32_t length = value->length();
Handle<Object> length_obj = isolate->factory()->NewNumberFromUint(length);
Object::SetProperty(isolate, proxy, isolate->factory()->length_string(),
length_obj, StoreOrigin::kNamed,
Just(ShouldThrow::kThrowOnError))
.Check();
return proxy;
}
static v8::Local<v8::FunctionTemplate> CreateTemplate(v8::Isolate* isolate) {
Local<v8::FunctionTemplate> templ =
IndexedDebugProxy::CreateTemplate(isolate);
templ->InstanceTemplate()->Set(isolate, "length",
v8::Number::New(isolate, 0));
return templ;
}
static uint32_t Count(Isolate* isolate, Handle<FixedArray> data) {
return WasmArray::cast(data->get(kObjectIndex))->length();
}
static Handle<Object> Get(Isolate* isolate, Handle<FixedArray> data,
uint32_t index) {
Handle<WasmArray> array(WasmArray::cast(data->get(kObjectIndex)), isolate);
Handle<WasmModuleObject> module(
WasmModuleObject::cast(data->get(kModuleIndex)), isolate);
return WasmValueObject::New(isolate, array->GetElement(index), module);
}
};
// static
Handle<WasmValueObject> WasmValueObject::New(
Isolate* isolate, const wasm::WasmValue& value,
Handle<WasmModuleObject> module_object) {
Handle<String> t;
Handle<Object> v;
switch (value.type().kind()) {
case wasm::kI8: {
// This can't be reached for most "top-level" things, only via nested
// calls for struct/array fields.
t = isolate->factory()->InternalizeString(base::StaticCharVector("i8"));
v = isolate->factory()->NewNumber(value.to_i8_unchecked());
break;
}
case wasm::kI16: {
// This can't be reached for most "top-level" things, only via nested
// calls for struct/array fields.
t = isolate->factory()->InternalizeString(base::StaticCharVector("i16"));
v = isolate->factory()->NewNumber(value.to_i16_unchecked());
break;
}
case wasm::kI32: {
t = isolate->factory()->InternalizeString(base::StaticCharVector("i32"));
v = isolate->factory()->NewNumberFromInt(value.to_i32_unchecked());
break;
}
case wasm::kI64: {
t = isolate->factory()->InternalizeString(base::StaticCharVector("i64"));
v = BigInt::FromInt64(isolate, value.to_i64_unchecked());
break;
}
case wasm::kF32: {
t = isolate->factory()->InternalizeString(base::StaticCharVector("f32"));
v = isolate->factory()->NewNumber(value.to_f32_unchecked());
break;
}
case wasm::kF64: {
t = isolate->factory()->InternalizeString(base::StaticCharVector("f64"));
v = isolate->factory()->NewNumber(value.to_f64_unchecked());
break;
}
case wasm::kS128: {
t = isolate->factory()->InternalizeString(base::StaticCharVector("v128"));
v = WasmSimd128ToString(isolate, value.to_s128_unchecked());
break;
}
case wasm::kRefNull:
case wasm::kRef: {
Handle<Object> ref = value.to_ref();
if (IsWasmStruct(*ref)) {
Tagged<WasmTypeInfo> type_info =
HeapObject::cast(*ref)->map()->wasm_type_info();
wasm::ValueType type = wasm::ValueType::FromIndex(
wasm::ValueKind::kRef, type_info->type_index());
// The cast is safe; structs always have the instance defined.
Handle<WasmModuleObject> module(
WasmInstanceObject::cast(type_info->instance())->module_object(),
isolate);
t = GetRefTypeName(isolate, type, module->native_module());
v = StructProxy::Create(isolate, Handle<WasmStruct>::cast(ref), module);
} else if (IsWasmArray(*ref)) {
Tagged<WasmTypeInfo> type_info =
HeapObject::cast(*ref)->map()->wasm_type_info();
wasm::ValueType type = wasm::ValueType::FromIndex(
wasm::ValueKind::kRef, type_info->type_index());
// The cast is safe; arrays always have the instance defined.
Handle<WasmModuleObject> module(
WasmInstanceObject::cast(type_info->instance())->module_object(),
isolate);
t = GetRefTypeName(isolate, type, module->native_module());
v = ArrayProxy::Create(isolate, Handle<WasmArray>::cast(ref), module);
} else if (IsWasmInternalFunction(*ref)) {
auto internal_fct = Handle<WasmInternalFunction>::cast(ref);
v = WasmInternalFunction::GetOrCreateExternal(internal_fct);
// If the module is not provided by the caller, retrieve it from the
// instance object. If the function was created in JavaScript using
// `new WebAssembly.Function(...)`, a module for name resolution is not
// available.
if (module_object.is_null() &&
IsWasmInstanceObject(internal_fct->ref())) {
module_object = handle(
WasmInstanceObject::cast(internal_fct->ref())->module_object(),
isolate);
}
t = GetRefTypeName(isolate, value.type(), module_object);
} else if (IsWasmNull(*ref)) {
// TODO(manoskouk): Is this value correct?
v = isolate->factory()->null_value();
t = GetRefTypeName(isolate, value.type(), module_object);
} else if (IsJSFunction(*ref) || IsSmi(*ref) || IsNull(*ref) ||
IsString(*ref) ||
value.type().is_reference_to(wasm::HeapType::kExtern) ||
value.type().is_reference_to(wasm::HeapType::kAny)) {
t = GetRefTypeName(isolate, value.type(), module_object);
v = ref;
} else {
// Fail gracefully.
base::EmbeddedVector<char, 64> error;
int len = SNPrintF(error, "unimplemented object type: %d",
HeapObject::cast(*ref)->map()->instance_type());
t = GetRefTypeName(isolate, value.type(), module_object);
v = isolate->factory()->InternalizeString(error.SubVector(0, len));
}
break;
}
case wasm::kRtt:
case wasm::kVoid:
case wasm::kBottom:
UNREACHABLE();
}
return New(isolate, t, v);
}
Handle<JSObject> GetWasmDebugProxy(WasmFrame* frame) {
return ContextProxy::Create(frame);
}
std::unique_ptr<debug::ScopeIterator> GetWasmScopeIterator(WasmFrame* frame) {
return std::make_unique<DebugWasmScopeIterator>(frame);
}
Handle<String> GetWasmFunctionDebugName(Isolate* isolate,
Handle<WasmInstanceObject> instance,
uint32_t func_index) {
Handle<WasmModuleObject> module_object(instance->module_object(), isolate);
wasm::NamesProvider* names =
module_object->native_module()->GetNamesProvider();