[wasm] Support undefined indirect table entries, behind a flag.

src/wasm/wasm-module.cc

Index: src/wasm/wasm-module.cc
diff --git a/src/wasm/wasm-module.cc b/src/wasm/wasm-module.cc
index 62b4ab274f3d8f93a30b9fb804ee344bb3b94a79..ceec1026706e7de6b4bf5396d9cc40cdd3136e45 100644
--- a/src/wasm/wasm-module.cc
+++ b/src/wasm/wasm-module.cc
@@ -144,12 +144,16 @@ void LoadDataSegments(const WasmModule* module, byte* mem_addr,
 
 Handle<FixedArray> BuildFunctionTable(Isolate* isolate,
                                       const WasmModule* module) {
-  if (module->function_table.size() == 0) {
+  // Compute the size of the indirect function table
+  uint32_t table_size = module->FunctionTableSize();
+  if (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++) {
+  for (uint32_t i = 0;
+       i < static_cast<uint32_t>(module->function_table.size());

[ritesht, 2016/06/21 23:16:33]

I have to cast this as the "set" function requires an int32.

+       ++i) {
     const WasmFunction* function =
         &module->functions[module->function_table[i]];
     fixed->set(i, Smi::FromInt(function->sig_index));
@@ -174,7 +178,7 @@ Handle<JSArrayBuffer> NewArrayBuffer(Isolate* isolate, size_t size,
 #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++) {
+  for (size_t i = 0; i < size; ++i) {
     DCHECK_EQ(0, bytes[i]);
   }
 #endif
@@ -310,7 +314,7 @@ bool LinkFunction(Handle<Code> unlinked,
 
 void LinkModuleFunctions(Isolate* isolate,
                          std::vector<Handle<Code>>& functions) {
-  for (size_t i = 0; i < functions.size(); i++) {
+  for (size_t i = 0; i < functions.size(); ++i) {
     Handle<Code> code = functions[i];
     bool modified = LinkFunction(code, functions, Code::WASM_FUNCTION);
     if (modified) {
@@ -342,7 +346,9 @@ WasmModule::WasmModule()
       mem_export(false),
       mem_external(false),
       start_function_index(-1),
-      origin(kWasmOrigin) {}
+      origin(kWasmOrigin),
+      globals_size(0),
+      indirect_table_size(0) {}
 
 static MaybeHandle<JSFunction> ReportFFIError(ErrorThrower& thrower,
                                               const char* error, uint32_t index,
@@ -514,7 +520,7 @@ void InitializeParallelCompilation(
     Isolate* isolate, const std::vector<WasmFunction>& functions,
     std::vector<compiler::WasmCompilationUnit*>& compilation_units,
     ModuleEnv& module_env, ErrorThrower& thrower) {
-  for (uint32_t i = FLAG_skip_compiling_wasm_funcs; i < functions.size(); i++) {
+  for (uint32_t i = FLAG_skip_compiling_wasm_funcs; i < functions.size(); ++i) {
     compilation_units[i] = new compiler::WasmCompilationUnit(
         &thrower, isolate, &module_env, &functions[i], i);
   }
@@ -530,7 +536,7 @@ uint32_t* StartCompilationTasks(
       Min(static_cast<size_t>(FLAG_wasm_num_compilation_tasks),
           V8::GetCurrentPlatform()->NumberOfAvailableBackgroundThreads());
   uint32_t* task_ids = new uint32_t[num_tasks];
-  for (size_t i = 0; i < num_tasks; i++) {
+  for (size_t i = 0; i < num_tasks; ++i) {
     WasmCompilationTask* task =
         new WasmCompilationTask(isolate, &compilation_units, &executed_units,
                                 pending_tasks.get(), &result_mutex, &next_unit);
@@ -547,7 +553,7 @@ void WaitForCompilationTasks(
   const size_t num_tasks =
       Min(static_cast<size_t>(FLAG_wasm_num_compilation_tasks),
           V8::GetCurrentPlatform()->NumberOfAvailableBackgroundThreads());
-  for (size_t i = 0; i < num_tasks; i++) {
+  for (size_t i = 0; i < num_tasks; ++i) {
     // If the task has not started yet, then we abort it. Otherwise we wait for
     // it to finish.
     if (!isolate->cancelable_task_manager()->TryAbort(task_ids[i])) {
@@ -646,7 +652,7 @@ void CompileSequentially(Isolate* isolate, const WasmModule* module,
   DCHECK(!thrower->error());
 
   for (uint32_t i = FLAG_skip_compiling_wasm_funcs;
-       i < module->functions.size(); i++) {
+       i < module->functions.size(); ++i) {
     const WasmFunction& func = module->functions[i];
 
     DCHECK_EQ(i, func.func_index);
@@ -667,12 +673,14 @@ void CompileSequentially(Isolate* isolate, const WasmModule* module,
 
 void PopulateFunctionTable(WasmModuleInstance* instance) {
   if (!instance->function_table.is_null()) {
-    int table_size = static_cast<int>(instance->module->function_table.size());
-    DCHECK_EQ(instance->function_table->length(), table_size * 2);
-    for (int i = 0; i < table_size; i++) {
-      instance->function_table->set(
-          i + table_size,
-          *instance->function_code[instance->module->function_table[i]]);
+    uint32_t table_size = instance->module->FunctionTableSize();
+    DCHECK_EQ(table_size * 2, instance->function_table->length());
+    uint32_t populated_table_size =
+        static_cast<uint32_t>(instance->module->function_table.size());
+    for (uint32_t i = 0; i < populated_table_size; ++i) {
+    instance->function_table->set(
+        i + table_size,
+        *instance->function_code[instance->module->function_table[i]]);
     }
   }
 }