Revert of [wasm] Refactor function name table and lookup

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 "src/base/atomic-utils.h"
 #include "src/macro-assembler.h"
 #include "src/objects.h"
 #include "src/property-descriptor.h"
 #include "src/v8.h"
 
@@ skipping 819 matching lines @@
         JSObject::AddProperty(exports_object, name, instance.mem_buffer,
                               READ_ONLY);
       }
     }
   }
 
   //-------------------------------------------------------------------------
   // Attach an array with function names and an array with offsets into that
   // first array.
   //-------------------------------------------------------------------------
-  instance.js_object->SetInternalField(
-      kWasmFunctionNamesArray,
-      *BuildFunctionNamesTable(isolate, module_env.module));
+  {
+    Handle<Object> arr = BuildFunctionNamesTable(isolate, module_env.module);
+    instance.js_object->SetInternalField(kWasmFunctionNamesArray, *arr);
+  }
 
   code_stats.Report();
 
   // 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 = instance.function_code[index];
     Handle<JSFunction> jsfunc = compiler::CompileJSToWasmWrapper(
@@ skipping 122 matching lines @@
   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;
 }
 
-Handle<Object> GetWasmFunctionNameOrNull(Isolate* isolate, Handle<Object> wasm,
-                                         uint32_t func_index) {
-  if (!wasm->IsUndefined()) {
-    Handle<ByteArray> func_names_arr_obj(
-        ByteArray::cast(Handle<JSObject>::cast(wasm)->GetInternalField(
-            kWasmFunctionNamesArray)),
-        isolate);
-    // TODO(clemens): Extract this from the module bytes; skip whole function
-    // name table.
-    Handle<Object> name;
-    if (GetWasmFunctionNameFromTable(func_names_arr_obj, func_index)
-            .ToHandle(&name)) {
-      return name;
-    }
-  }
-  return isolate->factory()->null_value();
-}
-
-Handle<String> GetWasmFunctionName(Isolate* isolate, Handle<Object> wasm,
-                                   uint32_t func_index) {
-  Handle<Object> name_or_null =
-      GetWasmFunctionNameOrNull(isolate, wasm, func_index);
-  if (!name_or_null->IsNull()) return Handle<String>::cast(name_or_null);
-  return isolate->factory()->NewStringFromStaticChars("<WASM UNNAMED>");
+MaybeHandle<String> GetWasmFunctionName(Handle<JSObject> wasm,
+                                        uint32_t func_index) {
+  DCHECK(IsWasmObject(wasm));
+  Object* func_names_arr_obj = wasm->GetInternalField(kWasmFunctionNamesArray);
+  Isolate* isolate = wasm->GetIsolate();
+  if (func_names_arr_obj->IsUndefined(isolate)) return Handle<String>::null();
+  return GetWasmFunctionNameFromTable(
+      handle(ByteArray::cast(func_names_arr_obj), isolate), func_index);
 }
 
 bool IsWasmObject(Handle<JSObject> object) {
   // TODO(clemensh): Check wasm byte header once we store a copy of the bytes.
   return object->GetInternalFieldCount() == kWasmModuleInternalFieldCount &&
          object->GetInternalField(kWasmModuleCodeTable)->IsFixedArray() &&
          object->GetInternalField(kWasmMemArrayBuffer)->IsJSArrayBuffer() &&
-         object->GetInternalField(kWasmFunctionNamesArray)->IsByteArray();
+         (object->GetInternalField(kWasmFunctionNamesArray)->IsByteArray() ||
+          object->GetInternalField(kWasmFunctionNamesArray)
+              ->IsUndefined(object->GetIsolate()));
 }
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8