[wasm] Implement WebAssembly.validate()

src/wasm/wasm-module.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 <memory>
 
 #include "src/base/atomic-utils.h"
 #include "src/code-stubs.h"
 
 #include "src/macro-assembler.h"
@@ skipping 1795 matching lines @@
     return nothing;
   }
   MaybeHandle<FixedArray> compiled_module =
       decoded_module->CompileFunctions(isolate, thrower);
   if (compiled_module.is_null()) return nothing;
 
   return CreateCompiledModuleObject(isolate, compiled_module.ToHandleChecked(),
                                     origin);
 }
 
+bool ValidateModuleBytes(Isolate* isolate, const byte* start, const byte* end,
+                         ErrorThrower* thrower, ModuleOrigin origin) {
+  Zone zone(isolate->allocator());
+  ModuleResult result =
+      DecodeWasmModule(isolate, &zone, start, end, false, origin);
+  if (result.val) delete result.val;

[Mircea Trofin, 2016/09/29 16:47:49]

if (result.val != nullptr) or even:

if (result.ok) {
  DCHECK_NOT_NULL(result.val);
  delete result.val;
}

+  return result.ok();
+}
+
 MaybeHandle<JSArrayBuffer> GetInstanceMemory(Isolate* isolate,
                                              Handle<JSObject> instance) {
   Object* mem = instance->GetInternalField(kWasmMemArrayBuffer);
   DCHECK(IsWasmObject(*instance));
   if (mem->IsUndefined(isolate)) return MaybeHandle<JSArrayBuffer>();
   return Handle<JSArrayBuffer>(JSArrayBuffer::cast(mem));
 }
 
 void SetInstanceMemory(Handle<JSObject> instance, JSArrayBuffer* buffer) {
   DisallowHeapAllocation no_gc;
@@ skipping 50 matching lines @@
   FixedArray* compiled_module =
       FixedArray::cast(instance->GetInternalField(kWasmCompiledModule));
   CHECK_NOT_NULL(GetModuleObject(compiled_module));
   CHECK(GetModuleObject(compiled_module)->cleared());
 }
 
 }  // namespace testing
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8