| // 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/macro-assembler.h" |
| #include "src/objects.h" |
| #include "src/v8.h" |
| |
| #include "src/simulator.h" |
| |
| #include "src/wasm/ast-decoder.h" |
| #include "src/wasm/module-decoder.h" |
| #include "src/wasm/wasm-module.h" |
| #include "src/wasm/wasm-result.h" |
| |
| #include "src/compiler/wasm-compiler.h" |
| |
| namespace v8 { |
| namespace internal { |
| namespace wasm { |
| |
| std::ostream& operator<<(std::ostream& os, const WasmModule& module) { |
| os << "WASM module with "; |
| os << (1 << module.min_mem_size_log2) << " min mem"; |
| os << (1 << module.max_mem_size_log2) << " max mem"; |
| if (module.functions) os << module.functions->size() << " functions"; |
| if (module.globals) os << module.functions->size() << " globals"; |
| if (module.data_segments) os << module.functions->size() << " data segments"; |
| return os; |
| } |
| |
| |
| std::ostream& operator<<(std::ostream& os, const WasmFunction& function) { |
| os << "WASM function with signature " << *function.sig; |
| |
| os << " locals: "; |
| if (function.local_i32_count) os << function.local_i32_count << " i32s "; |
| if (function.local_i64_count) os << function.local_i64_count << " i64s "; |
| if (function.local_f32_count) os << function.local_f32_count << " f32s "; |
| if (function.local_f64_count) os << function.local_f64_count << " f64s "; |
| |
| os << " code bytes: " |
| << (function.code_end_offset - function.code_start_offset); |
| return os; |
| } |
| |
| std::ostream& operator<<(std::ostream& os, const WasmFunctionName& pair) { |
| os << "#" << pair.function_->func_index << ":"; |
| if (pair.function_->name_offset > 0) { |
| if (pair.module_) { |
| os << pair.module_->GetName(pair.function_->name_offset); |
| } else { |
| os << "+" << pair.function_->func_index; |
| } |
| } else { |
| os << "?"; |
| } |
| return os; |
| } |
| |
| // A helper class for compiling multiple wasm functions that offers |
| // placeholder code objects for calling functions that are not yet compiled. |
| class WasmLinker { |
| public: |
| WasmLinker(Isolate* isolate, size_t size) |
| : isolate_(isolate), placeholder_code_(size), function_code_(size) {} |
| |
| // Get the code object for a function, allocating a placeholder if it has |
| // not yet been compiled. |
| Handle<Code> GetFunctionCode(uint32_t index) { |
| DCHECK(index < function_code_.size()); |
| if (function_code_[index].is_null()) { |
| // Create a placeholder code object and encode the corresponding index in |
| // the {constant_pool_offset} field of the code object. |
| // TODO(titzer): placeholder code objects are somewhat dangerous. |
| Handle<Code> self(nullptr, isolate_); |
| byte buffer[] = {0, 0, 0, 0, 0, 0, 0, 0}; // fake instructions. |
| CodeDesc desc = {buffer, 8, 8, 0, 0, nullptr}; |
| Handle<Code> code = isolate_->factory()->NewCode( |
| desc, Code::KindField::encode(Code::WASM_FUNCTION), self); |
| code->set_constant_pool_offset(index + kPlaceholderMarker); |
| placeholder_code_[index] = code; |
| function_code_[index] = code; |
| } |
| return function_code_[index]; |
| } |
| |
| void Finish(uint32_t index, Handle<Code> code) { |
| DCHECK(index < function_code_.size()); |
| function_code_[index] = code; |
| } |
| |
| void Link(Handle<FixedArray> function_table, |
| std::vector<uint16_t>* functions) { |
| for (size_t i = 0; i < function_code_.size(); i++) { |
| LinkFunction(function_code_[i]); |
| } |
| if (functions && !function_table.is_null()) { |
| int table_size = static_cast<int>(functions->size()); |
| DCHECK_EQ(function_table->length(), table_size * 2); |
| for (int i = 0; i < table_size; i++) { |
| function_table->set(i + table_size, *function_code_[functions->at(i)]); |
| } |
| } |
| } |
| |
| private: |
| static const int kPlaceholderMarker = 1000000000; |
| |
| Isolate* isolate_; |
| std::vector<Handle<Code>> placeholder_code_; |
| std::vector<Handle<Code>> function_code_; |
| |
| void LinkFunction(Handle<Code> code) { |
| bool modified = false; |
| int mode_mask = RelocInfo::kCodeTargetMask; |
| AllowDeferredHandleDereference embedding_raw_address; |
| for (RelocIterator it(*code, mode_mask); !it.done(); it.next()) { |
| RelocInfo::Mode mode = it.rinfo()->rmode(); |
| if (RelocInfo::IsCodeTarget(mode)) { |
| Code* target = |
| Code::GetCodeFromTargetAddress(it.rinfo()->target_address()); |
| if (target->kind() == Code::WASM_FUNCTION && |
| target->constant_pool_offset() >= kPlaceholderMarker) { |
| // Patch direct calls to placeholder code objects. |
| uint32_t index = target->constant_pool_offset() - kPlaceholderMarker; |
| CHECK(index < function_code_.size()); |
| Handle<Code> new_target = function_code_[index]; |
| if (target != *new_target) { |
| CHECK_EQ(*placeholder_code_[index], target); |
| it.rinfo()->set_target_address(new_target->instruction_start(), |
| SKIP_WRITE_BARRIER, |
| SKIP_ICACHE_FLUSH); |
| modified = true; |
| } |
| } |
| } |
| } |
| if (modified) { |
| Assembler::FlushICache(isolate_, code->instruction_start(), |
| code->instruction_size()); |
| } |
| } |
| }; |
| |
| namespace { |
| // Internal constants for the layout of the module object. |
| const int kWasmModuleInternalFieldCount = 4; |
| const int kWasmModuleFunctionTable = 0; |
| const int kWasmModuleCodeTable = 1; |
| const int kWasmMemArrayBuffer = 2; |
| const int kWasmGlobalsArrayBuffer = 3; |
| |
| |
| size_t AllocateGlobalsOffsets(std::vector<WasmGlobal>* globals) { |
| uint32_t offset = 0; |
| if (!globals) return 0; |
| for (WasmGlobal& global : *globals) { |
| byte size = WasmOpcodes::MemSize(global.type); |
| offset = (offset + size - 1) & ~(size - 1); // align |
| global.offset = offset; |
| offset += size; |
| } |
| return offset; |
| } |
| |
| |
| void LoadDataSegments(WasmModule* module, byte* mem_addr, size_t mem_size) { |
| for (const WasmDataSegment& segment : *module->data_segments) { |
| if (!segment.init) continue; |
| CHECK_LT(segment.dest_addr, mem_size); |
| CHECK_LE(segment.source_size, mem_size); |
| CHECK_LE(segment.dest_addr + segment.source_size, mem_size); |
| byte* addr = mem_addr + segment.dest_addr; |
| memcpy(addr, module->module_start + segment.source_offset, |
| segment.source_size); |
| } |
| } |
| |
| |
| Handle<FixedArray> BuildFunctionTable(Isolate* isolate, WasmModule* module) { |
| if (!module->function_table || module->function_table->size() == 0) { |
| return Handle<FixedArray>::null(); |
| } |
| int table_size = static_cast<int>(module->function_table->size()); |
| Handle<FixedArray> fixed = isolate->factory()->NewFixedArray(2 * table_size); |
| for (int i = 0; i < table_size; i++) { |
| WasmFunction* function = |
| &module->functions->at(module->function_table->at(i)); |
| fixed->set(i, Smi::FromInt(function->sig_index)); |
| } |
| return fixed; |
| } |
| |
| Handle<JSArrayBuffer> NewArrayBuffer(Isolate* isolate, size_t size, |
| byte** backing_store) { |
| if (size > (1 << WasmModule::kMaxMemSize)) { |
| // TODO(titzer): lift restriction on maximum memory allocated here. |
| *backing_store = nullptr; |
| return Handle<JSArrayBuffer>::null(); |
| } |
| void* memory = |
| isolate->array_buffer_allocator()->Allocate(static_cast<int>(size)); |
| if (!memory) { |
| *backing_store = nullptr; |
| return Handle<JSArrayBuffer>::null(); |
| } |
| |
| *backing_store = reinterpret_cast<byte*>(memory); |
| |
| #if DEBUG |
| // Double check the API allocator actually zero-initialized the memory. |
| byte* bytes = reinterpret_cast<byte*>(*backing_store); |
| for (size_t i = 0; i < size; i++) { |
| DCHECK_EQ(0, bytes[i]); |
| } |
| #endif |
| |
| Handle<JSArrayBuffer> buffer = isolate->factory()->NewJSArrayBuffer(); |
| JSArrayBuffer::Setup(buffer, isolate, false, memory, static_cast<int>(size)); |
| buffer->set_is_neuterable(false); |
| return buffer; |
| } |
| |
| // Set the memory for a module instance to be the {memory} array buffer. |
| void SetMemory(WasmModuleInstance* instance, Handle<JSArrayBuffer> memory) { |
| memory->set_is_neuterable(false); |
| instance->mem_start = reinterpret_cast<byte*>(memory->backing_store()); |
| instance->mem_size = memory->byte_length()->Number(); |
| instance->mem_buffer = memory; |
| } |
| |
| // Allocate memory for a module instance as a new JSArrayBuffer. |
| bool AllocateMemory(ErrorThrower* thrower, Isolate* isolate, |
| WasmModuleInstance* instance) { |
| DCHECK(instance->module); |
| DCHECK(instance->mem_buffer.is_null()); |
| |
| if (instance->module->min_mem_size_log2 > WasmModule::kMaxMemSize) { |
| thrower->Error("Out of memory: wasm memory too large"); |
| return false; |
| } |
| instance->mem_size = static_cast<size_t>(1) |
| << instance->module->min_mem_size_log2; |
| instance->mem_buffer = |
| NewArrayBuffer(isolate, instance->mem_size, &instance->mem_start); |
| if (!instance->mem_start) { |
| thrower->Error("Out of memory: wasm memory"); |
| instance->mem_size = 0; |
| return false; |
| } |
| return true; |
| } |
| |
| bool AllocateGlobals(ErrorThrower* thrower, Isolate* isolate, |
| WasmModuleInstance* instance) { |
| instance->globals_size = AllocateGlobalsOffsets(instance->module->globals); |
| |
| if (instance->globals_size > 0) { |
| instance->globals_buffer = NewArrayBuffer(isolate, instance->globals_size, |
| &instance->globals_start); |
| if (!instance->globals_start) { |
| // Not enough space for backing store of globals. |
| thrower->Error("Out of memory: wasm globals"); |
| return false; |
| } |
| } |
| return true; |
| } |
| } // namespace |
| |
| WasmModule::WasmModule() |
| : shared_isolate(nullptr), |
| module_start(nullptr), |
| module_end(nullptr), |
| min_mem_size_log2(0), |
| max_mem_size_log2(0), |
| mem_export(false), |
| mem_external(false), |
| start_function_index(-1), |
| globals(nullptr), |
| signatures(nullptr), |
| functions(nullptr), |
| data_segments(nullptr), |
| function_table(nullptr), |
| import_table(nullptr) {} |
| |
| WasmModule::~WasmModule() { |
| if (globals) delete globals; |
| if (signatures) delete signatures; |
| if (functions) delete functions; |
| if (data_segments) delete data_segments; |
| if (function_table) delete function_table; |
| if (import_table) delete import_table; |
| } |
| |
| static MaybeHandle<JSFunction> LookupFunction(ErrorThrower& thrower, |
| Handle<JSObject> ffi, |
| uint32_t index, |
| Handle<String> name, |
| const char* cstr) { |
| if (!ffi.is_null()) { |
| MaybeHandle<Object> result = Object::GetProperty(ffi, name); |
| if (!result.is_null()) { |
| Handle<Object> obj = result.ToHandleChecked(); |
| if (obj->IsJSFunction()) { |
| return Handle<JSFunction>::cast(obj); |
| } else { |
| thrower.Error("FFI function #%d:%s is not a JSFunction.", index, cstr); |
| return MaybeHandle<JSFunction>(); |
| } |
| } else { |
| thrower.Error("FFI function #%d:%s not found.", index, cstr); |
| return MaybeHandle<JSFunction>(); |
| } |
| } else { |
| thrower.Error("FFI table is not an object."); |
| return MaybeHandle<JSFunction>(); |
| } |
| } |
| |
| // Instantiates a wasm module as a JSObject. |
| // * allocates a backing store of {mem_size} bytes. |
| // * installs a named property "memory" for that buffer if exported |
| // * installs named properties on the object for exported functions |
| // * compiles wasm code to machine code |
| MaybeHandle<JSObject> WasmModule::Instantiate(Isolate* isolate, |
| Handle<JSObject> ffi, |
| Handle<JSArrayBuffer> memory) { |
| this->shared_isolate = isolate; // TODO(titzer): have a real shared isolate. |
| ErrorThrower thrower(isolate, "WasmModule::Instantiate()"); |
| Factory* factory = isolate->factory(); |
| |
| //------------------------------------------------------------------------- |
| // Allocate the instance and its JS counterpart. |
| //------------------------------------------------------------------------- |
| Handle<Map> map = factory->NewMap( |
| JS_OBJECT_TYPE, |
| JSObject::kHeaderSize + kWasmModuleInternalFieldCount * kPointerSize); |
| WasmModuleInstance instance(this); |
| std::vector<Handle<Code>> import_code; |
| instance.context = isolate->native_context(); |
| instance.js_object = factory->NewJSObjectFromMap(map, TENURED); |
| Handle<FixedArray> code_table = |
| factory->NewFixedArray(static_cast<int>(functions->size()), TENURED); |
| instance.js_object->SetInternalField(kWasmModuleCodeTable, *code_table); |
| |
| //------------------------------------------------------------------------- |
| // Allocate and initialize the linear memory. |
| //------------------------------------------------------------------------- |
| if (memory.is_null()) { |
| if (!AllocateMemory(&thrower, isolate, &instance)) { |
| return MaybeHandle<JSObject>(); |
| } |
| } else { |
| SetMemory(&instance, memory); |
| } |
| instance.js_object->SetInternalField(kWasmMemArrayBuffer, |
| *instance.mem_buffer); |
| LoadDataSegments(this, instance.mem_start, instance.mem_size); |
| |
| if (mem_export) { |
| // Export the memory as a named property. |
| Handle<String> name = factory->InternalizeUtf8String("memory"); |
| JSObject::AddProperty(instance.js_object, name, instance.mem_buffer, |
| READ_ONLY); |
| } |
| |
| //------------------------------------------------------------------------- |
| // Allocate the globals area if necessary. |
| //------------------------------------------------------------------------- |
| if (!AllocateGlobals(&thrower, isolate, &instance)) { |
| return MaybeHandle<JSObject>(); |
| } |
| if (!instance.globals_buffer.is_null()) { |
| instance.js_object->SetInternalField(kWasmGlobalsArrayBuffer, |
| *instance.globals_buffer); |
| } |
| |
| //------------------------------------------------------------------------- |
| // Compile wrappers to imported functions. |
| //------------------------------------------------------------------------- |
| uint32_t index = 0; |
| instance.function_table = BuildFunctionTable(isolate, this); |
| WasmLinker linker(isolate, functions->size()); |
| ModuleEnv module_env; |
| module_env.module = this; |
| module_env.instance = &instance; |
| module_env.linker = &linker; |
| module_env.asm_js = false; |
| |
| if (import_table->size() > 0) { |
| instance.import_code = &import_code; |
| instance.import_code->reserve(import_table->size()); |
| for (const WasmImport& import : *import_table) { |
| const char* cstr = GetName(import.function_name_offset); |
| Handle<String> name = factory->InternalizeUtf8String(cstr); |
| MaybeHandle<JSFunction> function = |
| LookupFunction(thrower, ffi, index, name, cstr); |
| if (function.is_null()) return MaybeHandle<JSObject>(); |
| Handle<Code> code = compiler::CompileWasmToJSWrapper( |
| isolate, &module_env, function.ToHandleChecked(), import.sig, cstr); |
| instance.import_code->push_back(code); |
| index++; |
| } |
| } |
| |
| //------------------------------------------------------------------------- |
| // Compile all functions in the module. |
| //------------------------------------------------------------------------- |
| |
| // First pass: compile each function and initialize the code table. |
| index = 0; |
| for (const WasmFunction& func : *functions) { |
| if (thrower.error()) break; |
| DCHECK_EQ(index, func.func_index); |
| |
| const char* cstr = GetName(func.name_offset); |
| Handle<String> name = factory->InternalizeUtf8String(cstr); |
| Handle<Code> code = Handle<Code>::null(); |
| Handle<JSFunction> function = Handle<JSFunction>::null(); |
| if (func.external) { |
| // Lookup external function in FFI object. |
| MaybeHandle<JSFunction> function = |
| LookupFunction(thrower, ffi, index, name, cstr); |
| if (function.is_null()) return MaybeHandle<JSObject>(); |
| code = compiler::CompileWasmToJSWrapper( |
| isolate, &module_env, function.ToHandleChecked(), func.sig, cstr); |
| } else { |
| // Compile the function. |
| code = compiler::CompileWasmFunction(thrower, isolate, &module_env, func); |
| if (code.is_null()) { |
| thrower.Error("Compilation of #%d:%s failed.", index, cstr); |
| return MaybeHandle<JSObject>(); |
| } |
| if (func.exported) { |
| function = compiler::CompileJSToWasmWrapper( |
| isolate, &module_env, name, code, instance.js_object, index); |
| } |
| } |
| if (!code.is_null()) { |
| // Install the code into the linker table. |
| linker.Finish(index, code); |
| code_table->set(index, *code); |
| } |
| if (func.exported) { |
| // Exported functions are installed as read-only properties on the module. |
| JSObject::AddProperty(instance.js_object, name, function, READ_ONLY); |
| } |
| index++; |
| } |
| |
| // Second pass: patch all direct call sites. |
| linker.Link(instance.function_table, this->function_table); |
| instance.js_object->SetInternalField(kWasmModuleFunctionTable, |
| Smi::FromInt(0)); |
| |
| // Run the start function if one was specified. |
| if (this->start_function_index >= 0) { |
| HandleScope scope(isolate); |
| uint32_t index = static_cast<uint32_t>(this->start_function_index); |
| Handle<String> name = isolate->factory()->NewStringFromStaticChars("start"); |
| Handle<Code> code = linker.GetFunctionCode(index); |
| Handle<JSFunction> jsfunc = compiler::CompileJSToWasmWrapper( |
| isolate, &module_env, name, code, instance.js_object, index); |
| |
| // Call the JS function. |
| Handle<Object> undefined(isolate->heap()->undefined_value(), isolate); |
| MaybeHandle<Object> retval = |
| Execution::Call(isolate, jsfunc, undefined, 0, nullptr); |
| |
| if (retval.is_null()) { |
| thrower.Error("WASM.instantiateModule(): start function failed"); |
| } |
| } |
| return instance.js_object; |
| } |
| |
| |
| Handle<Code> ModuleEnv::GetFunctionCode(uint32_t index) { |
| DCHECK(IsValidFunction(index)); |
| if (linker) return linker->GetFunctionCode(index); |
| if (instance && instance->function_code) { |
| return instance->function_code->at(index); |
| } |
| return Handle<Code>::null(); |
| } |
| |
| Handle<Code> ModuleEnv::GetImportCode(uint32_t index) { |
| DCHECK(IsValidImport(index)); |
| if (instance && instance->import_code) { |
| return instance->import_code->at(index); |
| } |
| return Handle<Code>::null(); |
| } |
| |
| compiler::CallDescriptor* ModuleEnv::GetCallDescriptor(Zone* zone, |
| uint32_t index) { |
| DCHECK(IsValidFunction(index)); |
| // Always make a direct call to whatever is in the table at that location. |
| // A wrapper will be generated for FFI calls. |
| WasmFunction* function = &module->functions->at(index); |
| return GetWasmCallDescriptor(zone, function->sig); |
| } |
| |
| |
| int32_t CompileAndRunWasmModule(Isolate* isolate, const byte* module_start, |
| const byte* module_end, bool asm_js) { |
| HandleScope scope(isolate); |
| Zone zone; |
| // Decode the module, but don't verify function bodies, since we'll |
| // be compiling them anyway. |
| ModuleResult result = |
| DecodeWasmModule(isolate, &zone, module_start, module_end, false, false); |
| if (result.failed()) { |
| // Module verification failed. throw. |
| std::ostringstream str; |
| str << "WASM.compileRun() failed: " << result; |
| isolate->Throw( |
| *isolate->factory()->NewStringFromAsciiChecked(str.str().c_str())); |
| return -1; |
| } |
| |
| int32_t retval = CompileAndRunWasmModule(isolate, result.val); |
| delete result.val; |
| return retval; |
| } |
| |
| |
| int32_t CompileAndRunWasmModule(Isolate* isolate, WasmModule* module) { |
| ErrorThrower thrower(isolate, "CompileAndRunWasmModule"); |
| WasmModuleInstance instance(module); |
| |
| // Allocate and initialize the linear memory. |
| if (!AllocateMemory(&thrower, isolate, &instance)) { |
| return -1; |
| } |
| LoadDataSegments(module, instance.mem_start, instance.mem_size); |
| |
| // Allocate the globals area if necessary. |
| if (!AllocateGlobals(&thrower, isolate, &instance)) { |
| return -1; |
| } |
| |
| // Build the function table. |
| instance.function_table = BuildFunctionTable(isolate, module); |
| |
| // Create module environment. |
| WasmLinker linker(isolate, module->functions->size()); |
| ModuleEnv module_env; |
| module_env.module = module; |
| module_env.instance = &instance; |
| module_env.linker = &linker; |
| module_env.asm_js = false; |
| |
| // Compile all functions. |
| Handle<Code> main_code = Handle<Code>::null(); // record last code. |
| uint32_t index = 0; |
| int main_index = 0; |
| for (const WasmFunction& func : *module->functions) { |
| DCHECK_EQ(index, func.func_index); |
| if (!func.external) { |
| // Compile the function and install it in the code table. |
| Handle<Code> code = |
| compiler::CompileWasmFunction(thrower, isolate, &module_env, func); |
| if (!code.is_null()) { |
| if (func.exported) { |
| main_code = code; |
| main_index = index; |
| } |
| linker.Finish(index, code); |
| } |
| if (thrower.error()) return -1; |
| } |
| index++; |
| } |
| |
| if (main_code.is_null()) { |
| thrower.Error("WASM.compileRun() failed: no main code found"); |
| return -1; |
| } |
| |
| linker.Link(instance.function_table, instance.module->function_table); |
| |
| // Wrap the main code so it can be called as a JS function. |
| Handle<String> name = isolate->factory()->NewStringFromStaticChars("main"); |
| Handle<JSObject> module_object = Handle<JSObject>(0, isolate); |
| Handle<JSFunction> jsfunc = compiler::CompileJSToWasmWrapper( |
| isolate, &module_env, name, main_code, module_object, main_index); |
| |
| // Call the JS function. |
| Handle<Object> undefined(isolate->heap()->undefined_value(), isolate); |
| MaybeHandle<Object> retval = |
| Execution::Call(isolate, jsfunc, undefined, 0, nullptr); |
| |
| // The result should be a number. |
| if (retval.is_null()) { |
| thrower.Error("WASM.compileRun() failed: Invocation was null"); |
| return -1; |
| } |
| Handle<Object> result = retval.ToHandleChecked(); |
| if (result->IsSmi()) { |
| return Smi::cast(*result)->value(); |
| } |
| if (result->IsHeapNumber()) { |
| return static_cast<int32_t>(HeapNumber::cast(*result)->value()); |
| } |
| thrower.Error("WASM.compileRun() failed: Return value should be number"); |
| return -1; |
| } |
| } // namespace wasm |
| } // namespace internal |
| } // namespace v8 |