[wasm] Initial signal handler

src/runtime/runtime-wasm.cc

 // Copyright 2016 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/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/assembler.h"
 #include "src/compiler/wasm-compiler.h"
 #include "src/conversions.h"
 #include "src/debug/debug.h"
 #include "src/factory.h"
 #include "src/frames-inl.h"
 #include "src/objects-inl.h"
+#include "src/trap-handler/trap-handler.h"
 #include "src/v8memory.h"
 #include "src/wasm/wasm-module.h"
 #include "src/wasm/wasm-objects.h"
 #include "src/wasm/wasm-opcodes.h"
 
 namespace v8 {
 namespace internal {
 
 namespace {
 Handle<WasmInstanceObject> GetWasmInstanceOnStackTop(Isolate* isolate) {
@@ skipping 128 matching lines @@
   HandleScope scope(isolate);
   DCHECK_EQ(1, args.length());
   Object* exception = args[0];
   // The unwinder will only deliver exceptions to wasm if the exception is a
   // Number or a Smi (which we have just converted to a Number.) This logic
   // lives in Isolate::is_catchable_by_wasm(Object*).
   CHECK(exception->IsNumber());
   return exception;
 }
 
+RUNTIME_FUNCTION(Runtime_SetThreadInWasm) {
+  DCHECK(!trap_handler::IsThreadInWasm());
+  trap_handler::SetThreadInWasm();
+  return isolate->heap()->undefined_value();
+}
+
+RUNTIME_FUNCTION(Runtime_ClearThreadInWasm) {
+  DCHECK(trap_handler::IsThreadInWasm());
+  trap_handler::ClearThreadInWasm();
+  return isolate->heap()->undefined_value();
+}
+
 RUNTIME_FUNCTION(Runtime_WasmRunInterpreter) {
   DCHECK(args.length() == 3);
   HandleScope scope(isolate);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, instance_obj, 0);
   CONVERT_NUMBER_CHECKED(int32_t, func_index, Int32, args[1]);
   CONVERT_ARG_HANDLE_CHECKED(Object, arg_buffer_obj, 2);
   CHECK(WasmInstanceObject::IsWasmInstanceObject(*instance_obj));
   Handle<WasmInstanceObject> instance =
       Handle<WasmInstanceObject>::cast(instance_obj);
 
   // The arg buffer is the raw pointer to the caller's stack. It looks like a
   // Smi (lowest bit not set, as checked by IsSmi), but is no valid Smi. We just
   // cast it back to the raw pointer.
   CHECK(!arg_buffer_obj->IsHeapObject());
   CHECK(arg_buffer_obj->IsSmi());
   uint8_t* arg_buffer = reinterpret_cast<uint8_t*>(*arg_buffer_obj);
 
   // Set the current isolate's context, saving the previous one.
   SaveContext save(isolate);
   isolate->set_context(*instance->compiled_module()->native_context());
 
   instance->debug_info()->RunInterpreter(func_index, arg_buffer);
   return isolate->heap()->undefined_value();
 }
 
 }  // namespace internal
 }  // namespace v8