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

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 126 matching lines @@
     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,
                                       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));
   }
   return fixed;
 }
 
 Handle<JSArrayBuffer> NewArrayBuffer(Isolate* isolate, size_t size,
                                      byte** backing_store) {
   *backing_store = nullptr;
   if (size > (WasmModule::kMaxMemPages * WasmModule::kPageSize)) {
     // TODO(titzer): lift restriction on maximum memory allocated here.
     return Handle<JSArrayBuffer>::null();
   }
   void* memory = isolate->array_buffer_allocator()->Allocate(size);
   if (memory == 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++) {
+  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;
 }
 
@@ skipping 115 matching lines @@
           modified = true;
         }
       }
     }
   }
   return modified;
 }
 
 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) {
       Assembler::FlushICache(isolate, code->instruction_start(),
                              code->instruction_size());
     }
   }
 }
 
 void LinkImports(Isolate* isolate, std::vector<Handle<Code>>& functions,
@@ skipping 11 matching lines @@
 }  // namespace
 
 WasmModule::WasmModule()
     : module_start(nullptr),
       module_end(nullptr),
       min_mem_pages(0),
       max_mem_pages(0),
       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,
                                               wasm::WasmName module_name,
                                               wasm::WasmName function_name) {
   if (!function_name.is_empty()) {
     thrower.Error("Import #%d module=\"%.*s\" function=\"%.*s\" error: %s",
                   index, module_name.length(), module_name.start(),
                   function_name.length(), function_name.start(), error);
   } else {
@@ skipping 151 matching lines @@
       instance->import_code[index] = code;
     }
   }
   return true;
 }
 
 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);
   }
 }
 
 uint32_t* StartCompilationTasks(
     Isolate* isolate,
     std::vector<compiler::WasmCompilationUnit*>& compilation_units,
     std::queue<compiler::WasmCompilationUnit*>& executed_units,
     const base::SmartPointer<base::Semaphore>& pending_tasks,
     base::Mutex& result_mutex, base::AtomicNumber<size_t>& next_unit) {
   const size_t num_tasks =
       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);
     task_ids[i] = task->id();
     V8::GetCurrentPlatform()->CallOnBackgroundThread(
         task, v8::Platform::kShortRunningTask);
   }
   return task_ids;
 }
 
 void WaitForCompilationTasks(
     Isolate* isolate, uint32_t* task_ids,
     const base::SmartPointer<base::Semaphore>& pending_tasks) {
   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])) {
       pending_tasks->Wait();
     }
   }
 }
 
 void FinishCompilationUnits(
     std::queue<compiler::WasmCompilationUnit*>& executed_units,
@@ skipping 78 matching lines @@
   // Finish the compilation of the remaining compilation units.
   FinishCompilationUnits(executed_units, functions, result_mutex);
 }
 
 void CompileSequentially(Isolate* isolate, const WasmModule* module,
                          std::vector<Handle<Code>>& functions,
                          ErrorThrower* thrower, ModuleEnv* module_env) {
   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);
     WasmName str = module->GetName(func.name_offset, func.name_length);
     Handle<Code> code = Handle<Code>::null();
     // Compile the function.
     code = compiler::WasmCompilationUnit::CompileWasmFunction(
         thrower, isolate, module_env, &func);
     if (code.is_null()) {
       thrower->Error("Compilation of #%d:%.*s failed.", i, str.length(),
                      str.start());
       break;
     }
       // Install the code into the linker table.
     functions[i] = code;
   }
 }
 
 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]]);
     }
   }
 }
 }  // namespace
 
 void SetDeoptimizationData(Factory* factory, Handle<JSObject> js_object,
                            std::vector<Handle<Code>>& functions) {
   for (size_t i = FLAG_skip_compiling_wasm_funcs; i < functions.size(); ++i) {
     Handle<Code> code = functions[i];
     DCHECK(code->deoptimization_data() == nullptr ||
@@ skipping 429 matching lines @@
   Object* info = wasm->GetInternalField(kWasmDebugInfo);
   if (!info->IsUndefined(wasm->GetIsolate())) return WasmDebugInfo::cast(info);
   Handle<WasmDebugInfo> new_info = WasmDebugInfo::New(handle(wasm));
   wasm->SetInternalField(kWasmDebugInfo, *new_info);
   return *new_info;
 }
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8