[Atomics] code stubs for atomic operations

src/runtime/runtime-atomics.cc

Index: src/runtime/runtime-atomics.cc
diff --git a/src/runtime/runtime-atomics.cc b/src/runtime/runtime-atomics.cc
index 94d98d4ffaf77a46e4aec1cb088bd55b36e406e4..6dd89949aeb5e858e1e204046d8b784a514ae54e 100644
--- a/src/runtime/runtime-atomics.cc
+++ b/src/runtime/runtime-atomics.cc
@@ -33,13 +33,6 @@ inline T CompareExchangeSeqCst(T* p, T oldval, T newval) {
 }
 
 template <typename T>
-inline T LoadSeqCst(T* p) {
-  T result;
-  __atomic_load(p, &result, __ATOMIC_SEQ_CST);
-  return result;
-}
-
-template <typename T>
 inline void StoreSeqCst(T* p, T value) {
   __atomic_store_n(p, value, __ATOMIC_SEQ_CST);
 }
@@ -117,7 +110,6 @@ inline T ExchangeSeqCst(T* p, T value) {
                                               bit_cast<vctype>(newval),     \
                                               bit_cast<vctype>(oldval));    \
   }                                                                         \
-  inline type LoadSeqCst(type* p) { return *p; }                            \
   inline void StoreSeqCst(type* p, type value) {                            \
     InterlockedExchange##suffix(reinterpret_cast<vctype*>(p),               \
                                 bit_cast<vctype>(value));                   \
@@ -216,13 +208,6 @@ inline Object* DoCompareExchange(Isolate* isolate, void* buffer, size_t index,
 
 
 template <typename T>
-inline Object* DoLoad(Isolate* isolate, void* buffer, size_t index) {
-  T result = LoadSeqCst(static_cast<T*>(buffer) + index);
-  return ToObject(isolate, result);
-}
-
-
-template <typename T>
 inline Object* DoStore(Isolate* isolate, void* buffer, size_t index,
                        Handle<Object> obj) {
   T value = FromObject<T>(obj);
@@ -365,6 +350,29 @@ inline Object* DoExchangeUint8Clamped(Isolate* isolate, void* buffer,
   V(Uint32, uint32, UINT32, uint32_t, 4) \
   V(Int32, int32, INT32, int32_t, 4)
 
+RUNTIME_FUNCTION(Runtime_ThrowNotIntegerSharedTypedArrayError) {
+  HandleScope scope(isolate);
+  DCHECK_EQ(1, args.length());
+  CONVERT_ARG_HANDLE_CHECKED(Object, value, 0);
+  THROW_NEW_ERROR_RETURN_FAILURE(
+      isolate,
+      NewTypeError(MessageTemplate::kNotIntegerSharedTypedArray, value));
+}
+
+RUNTIME_FUNCTION(Runtime_ThrowNotInt32SharedTypedArrayError) {
+  HandleScope scope(isolate);
+  DCHECK_EQ(1, args.length());
+  CONVERT_ARG_HANDLE_CHECKED(Object, value, 0);
+  THROW_NEW_ERROR_RETURN_FAILURE(
+      isolate, NewTypeError(MessageTemplate::kNotInt32SharedTypedArray, value));
+}
+
+RUNTIME_FUNCTION(Runtime_ThrowInvalidAtomicAccessIndexError) {
+  HandleScope scope(isolate);
+  DCHECK_EQ(0, args.length());
+  THROW_NEW_ERROR_RETURN_FAILURE(
+      isolate, NewRangeError(MessageTemplate::kInvalidAtomicAccessIndex));
+}
 
 RUNTIME_FUNCTION(Runtime_AtomicsCompareExchange) {
   HandleScope scope(isolate);
@@ -400,37 +408,6 @@ RUNTIME_FUNCTION(Runtime_AtomicsCompareExchange) {
 }
 
 
-RUNTIME_FUNCTION(Runtime_AtomicsLoad) {
-  HandleScope scope(isolate);
-  DCHECK(args.length() == 2);
-  CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, sta, 0);
-  CONVERT_SIZE_ARG_CHECKED(index, 1);
-  RUNTIME_ASSERT(sta->GetBuffer()->is_shared());
-  RUNTIME_ASSERT(index < NumberToSize(isolate, sta->length()));
-
-  uint8_t* source = static_cast<uint8_t*>(sta->GetBuffer()->backing_store()) +
-                    NumberToSize(isolate, sta->byte_offset());
-
-  switch (sta->type()) {
-#define TYPED_ARRAY_CASE(Type, typeName, TYPE, ctype, size) \
-  case kExternal##Type##Array:                              \
-    return DoLoad<ctype>(isolate, source, index);
-
-    INTEGER_TYPED_ARRAYS(TYPED_ARRAY_CASE)
-#undef TYPED_ARRAY_CASE
-
-    case kExternalUint8ClampedArray:
-      return DoLoad<uint8_t>(isolate, source, index);
-
-    default:
-      break;
-  }
-
-  UNREACHABLE();
-  return isolate->heap()->undefined_value();
-}
-
-
 RUNTIME_FUNCTION(Runtime_AtomicsStore) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 3);