[rab/gsab] Simplify JSFunction::GetDerivedRabGsabMap

Bug: v8:11111
Change-Id: I0bea83be43f9749b95caed146224d21b5128a478
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2904207
Commit-Queue: Marja Hölttä <marja@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Shu-yu Guo <syg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74665}

src/objects/contexts.h

@@ -62,6 +62,30 @@ enum ContextLookupFlags {
   V(CONTINUATION_PRESERVED_EMBEDDER_DATA_INDEX, HeapObject,                    \
     continuation_preserved_embedder_data)                                      \
   NATIVE_CONTEXT_INTRINSIC_FUNCTIONS(V)                                        \
+  /* TypedArray constructors - these must stay in order! */                    \
+  V(UINT8_ARRAY_FUN_INDEX, JSFunction, uint8_array_fun)                        \
+  V(INT8_ARRAY_FUN_INDEX, JSFunction, int8_array_fun)                          \
+  V(UINT16_ARRAY_FUN_INDEX, JSFunction, uint16_array_fun)                      \
+  V(INT16_ARRAY_FUN_INDEX, JSFunction, int16_array_fun)                        \
+  V(UINT32_ARRAY_FUN_INDEX, JSFunction, uint32_array_fun)                      \
+  V(INT32_ARRAY_FUN_INDEX, JSFunction, int32_array_fun)                        \
+  V(FLOAT32_ARRAY_FUN_INDEX, JSFunction, float32_array_fun)                    \
+  V(FLOAT64_ARRAY_FUN_INDEX, JSFunction, float64_array_fun)                    \
+  V(UINT8_CLAMPED_ARRAY_FUN_INDEX, JSFunction, uint8_clamped_array_fun)        \
+  V(BIGUINT64_ARRAY_FUN_INDEX, JSFunction, biguint64_array_fun)                \
+  V(BIGINT64_ARRAY_FUN_INDEX, JSFunction, bigint64_array_fun)                  \
+  V(RAB_GSAB_UINT8_ARRAY_MAP_INDEX, Map, rab_gsab_uint8_array_map)             \
+  V(RAB_GSAB_INT8_ARRAY_MAP_INDEX, Map, rab_gsab_int8_array_map)               \
+  V(RAB_GSAB_UINT16_ARRAY_MAP_INDEX, Map, rab_gsab_uint16_array_map)           \
+  V(RAB_GSAB_INT16_ARRAY_MAP_INDEX, Map, rab_gsab_int16_array_map)             \
+  V(RAB_GSAB_UINT32_ARRAY_MAP_INDEX, Map, rab_gsab_uint32_array_map)           \
+  V(RAB_GSAB_INT32_ARRAY_MAP_INDEX, Map, rab_gsab_int32_array_map)             \
+  V(RAB_GSAB_FLOAT32_ARRAY_MAP_INDEX, Map, rab_gsab_float32_array_map)         \
+  V(RAB_GSAB_FLOAT64_ARRAY_MAP_INDEX, Map, rab_gsab_float64_array_map)         \
+  V(RAB_GSAB_UINT8_CLAMPED_ARRAY_MAP_INDEX, Map,                               \
+    rab_gsab_uint8_clamped_array_map)                                          \
+  V(RAB_GSAB_BIGUINT64_ARRAY_MAP_INDEX, Map, rab_gsab_biguint64_array_map)     \
+  V(RAB_GSAB_BIGINT64_ARRAY_MAP_INDEX, Map, rab_gsab_bigint64_array_map)       \
   /* Below is alpha-sorted */                                                  \
   V(ACCESSOR_PROPERTY_DESCRIPTOR_MAP_INDEX, Map,                               \
     accessor_property_descriptor_map)                                          \
@@ -78,8 +102,6 @@ enum ContextLookupFlags {
     async_generator_function_function)                                         \
   V(ATOMICS_OBJECT, JSObject, atomics_object)                                  \
   V(BIGINT_FUNCTION_INDEX, JSFunction, bigint_function)                        \
-  V(BIGINT64_ARRAY_FUN_INDEX, JSFunction, bigint64_array_fun)                  \
-  V(BIGUINT64_ARRAY_FUN_INDEX, JSFunction, biguint64_array_fun)                \
   V(BOOLEAN_FUNCTION_INDEX, JSFunction, boolean_function)                      \
   V(BOUND_FUNCTION_WITH_CONSTRUCTOR_MAP_INDEX, Map,                            \
     bound_function_with_constructor_map)                                       \
@@ -104,8 +126,6 @@ enum ContextLookupFlags {
   V(FAST_ALIASED_ARGUMENTS_MAP_INDEX, Map, fast_aliased_arguments_map)         \
   V(FAST_TEMPLATE_INSTANTIATIONS_CACHE_INDEX, FixedArray,                      \
     fast_template_instantiations_cache)                                        \
-  V(FLOAT32_ARRAY_FUN_INDEX, JSFunction, float32_array_fun)                    \
-  V(FLOAT64_ARRAY_FUN_INDEX, JSFunction, float64_array_fun)                    \
   V(FUNCTION_FUNCTION_INDEX, JSFunction, function_function)                    \
   V(GENERATOR_FUNCTION_FUNCTION_INDEX, JSFunction,                             \
     generator_function_function)                                               \
@@ -139,9 +159,6 @@ enum ContextLookupFlags {
   V(INITIAL_STRING_PROTOTYPE_INDEX, JSObject, initial_string_prototype)        \
   V(INITIAL_WEAKMAP_PROTOTYPE_MAP_INDEX, Map, initial_weakmap_prototype_map)   \
   V(INITIAL_WEAKSET_PROTOTYPE_MAP_INDEX, Map, initial_weakset_prototype_map)   \
-  V(INT16_ARRAY_FUN_INDEX, JSFunction, int16_array_fun)                        \
-  V(INT32_ARRAY_FUN_INDEX, JSFunction, int32_array_fun)                        \
-  V(INT8_ARRAY_FUN_INDEX, JSFunction, int8_array_fun)                          \
   V(INTL_COLLATOR_FUNCTION_INDEX, JSFunction, intl_collator_function)          \
   V(INTL_DATE_TIME_FORMAT_FUNCTION_INDEX, JSFunction,                          \
     intl_date_time_format_function)                                            \
@@ -212,18 +229,6 @@ enum ContextLookupFlags {
   V(PROXY_MAP_INDEX, Map, proxy_map)                                           \
   V(PROXY_REVOCABLE_RESULT_MAP_INDEX, Map, proxy_revocable_result_map)         \
   V(PROMISE_PROTOTYPE_INDEX, JSObject, promise_prototype)                      \
-  V(RAB_GSAB_UINT8_ARRAY_MAP_INDEX, Map, rab_gsab_uint8_array_map)             \
-  V(RAB_GSAB_INT8_ARRAY_MAP_INDEX, Map, rab_gsab_int8_array_map)               \
-  V(RAB_GSAB_UINT16_ARRAY_MAP_INDEX, Map, rab_gsab_uint16_array_map)           \
-  V(RAB_GSAB_INT16_ARRAY_MAP_INDEX, Map, rab_gsab_int16_array_map)             \
-  V(RAB_GSAB_UINT32_ARRAY_MAP_INDEX, Map, rab_gsab_uint32_array_map)           \
-  V(RAB_GSAB_INT32_ARRAY_MAP_INDEX, Map, rab_gsab_int32_array_map)             \
-  V(RAB_GSAB_FLOAT32_ARRAY_MAP_INDEX, Map, rab_gsab_float32_array_map)         \
-  V(RAB_GSAB_FLOAT64_ARRAY_MAP_INDEX, Map, rab_gsab_float64_array_map)         \
-  V(RAB_GSAB_UINT8_CLAMPED_ARRAY_MAP_INDEX, Map,                               \
-    rab_gsab_uint8_clamped_array_map)                                          \
-  V(RAB_GSAB_BIGUINT64_ARRAY_MAP_INDEX, Map, rab_gsab_biguint64_array_map)     \
-  V(RAB_GSAB_BIGINT64_ARRAY_MAP_INDEX, Map, rab_gsab_bigint64_array_map)       \
   V(RECORDER_CONTEXT_ID, Object, recorder_context_id)                          \
   V(REGEXP_EXEC_FUNCTION_INDEX, JSFunction, regexp_exec_function)              \
   V(REGEXP_FUNCTION_INDEX, JSFunction, regexp_function)                        \
@@ -298,10 +303,6 @@ enum ContextLookupFlags {
   V(TEMPLATE_WEAKMAP_INDEX, HeapObject, template_weakmap)                      \
   V(TYPED_ARRAY_FUN_INDEX, JSFunction, typed_array_function)                   \
   V(TYPED_ARRAY_PROTOTYPE_INDEX, JSObject, typed_array_prototype)              \
-  V(UINT16_ARRAY_FUN_INDEX, JSFunction, uint16_array_fun)                      \
-  V(UINT32_ARRAY_FUN_INDEX, JSFunction, uint32_array_fun)                      \
-  V(UINT8_ARRAY_FUN_INDEX, JSFunction, uint8_array_fun)                        \
-  V(UINT8_CLAMPED_ARRAY_FUN_INDEX, JSFunction, uint8_clamped_array_fun)        \
   V(ARRAY_ENTRIES_ITERATOR_INDEX, JSFunction, array_entries_iterator)          \
   V(ARRAY_FOR_EACH_ITERATOR_INDEX, JSFunction, array_for_each_iterator)        \
   V(ARRAY_KEYS_ITERATOR_INDEX, JSFunction, array_keys_iterator)                \
@@ -540,6 +541,10 @@ class Context : public TorqueGeneratedContext<Context, HeapObject> {
   static const int FIRST_FUNCTION_MAP_INDEX = SLOPPY_FUNCTION_MAP_INDEX;
   static const int LAST_FUNCTION_MAP_INDEX = CLASS_FUNCTION_MAP_INDEX;
 
+  static const int FIRST_FIXED_TYPED_ARRAY_FUN_INDEX = UINT8_ARRAY_FUN_INDEX;
+  static const int FIRST_RAB_GSAB_TYPED_ARRAY_MAP_INDEX =
+      RAB_GSAB_UINT8_ARRAY_MAP_INDEX;
+
   static const int kNoContext = 0;
   static const int kInvalidContext = 1;
 

src/objects/js-function.cc

@@ -796,49 +796,55 @@ MaybeHandle<Map> JSFunction::GetDerivedMap(Isolate* isolate,
   return map;
 }
 
+namespace {
+
+// Assert that the computations in TypedArrayElementsKindToConstructorIndex and
+// TypedArrayElementsKindToRabGsabCtorIndex are sound.
+#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype)                         \
+  STATIC_ASSERT(Context::TYPE##_ARRAY_FUN_INDEX ==                        \
+                Context::FIRST_FIXED_TYPED_ARRAY_FUN_INDEX +              \
+                    ElementsKind::TYPE##_ELEMENTS -                       \
+                    ElementsKind::FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND); \
+  STATIC_ASSERT(Context::RAB_GSAB_##TYPE##_ARRAY_MAP_INDEX ==             \
+                Context::FIRST_RAB_GSAB_TYPED_ARRAY_MAP_INDEX +           \
+                    ElementsKind::TYPE##_ELEMENTS -                       \
+                    ElementsKind::FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND);
+
+TYPED_ARRAYS(TYPED_ARRAY_CASE)
+#undef TYPED_ARRAY_CASE
+
+int TypedArrayElementsKindToConstructorIndex(ElementsKind elements_kind) {
+  return Context::FIRST_FIXED_TYPED_ARRAY_FUN_INDEX + elements_kind -
+         ElementsKind::FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND;
+}
+
+int TypedArrayElementsKindToRabGsabCtorIndex(ElementsKind elements_kind) {
+  return Context::FIRST_RAB_GSAB_TYPED_ARRAY_MAP_INDEX + elements_kind -
+         ElementsKind::FIRST_FIXED_TYPED_ARRAY_ELEMENTS_KIND;
+}
+
+}  // namespace
+
 Handle<Map> JSFunction::GetDerivedRabGsabMap(Isolate* isolate,
                                              Handle<JSFunction> constructor,
                                              Handle<JSReceiver> new_target) {
+  Handle<Map> map =
+      GetDerivedMap(isolate, constructor, new_target).ToHandleChecked();
   {
     DisallowHeapAllocation no_alloc;
     NativeContext context = isolate->context().native_context();
-    if (*new_target == context.uint8_array_fun()) {
-      return handle(context.rab_gsab_uint8_array_map(), isolate);
-    }
-    if (*new_target == context.int8_array_fun()) {
-      return handle(context.rab_gsab_int8_array_map(), isolate);
-    }
-    if (*new_target == context.uint16_array_fun()) {
-      return handle(context.rab_gsab_uint16_array_map(), isolate);
-    }
-    if (*new_target == context.int16_array_fun()) {
-      return handle(context.rab_gsab_int16_array_map(), isolate);
-    }
-    if (*new_target == context.uint32_array_fun()) {
-      return handle(context.rab_gsab_uint32_array_map(), isolate);
-    }
-    if (*new_target == context.int32_array_fun()) {
-      return handle(context.rab_gsab_int32_array_map(), isolate);
-    }
-    if (*new_target == context.float32_array_fun()) {
-      return handle(context.rab_gsab_float32_array_map(), isolate);
-    }
-    if (*new_target == context.float64_array_fun()) {
-      return handle(context.rab_gsab_float64_array_map(), isolate);
-    }
-    if (*new_target == context.biguint64_array_fun()) {
-      return handle(context.rab_gsab_biguint64_array_map(), isolate);
-    }
-    if (*new_target == context.bigint64_array_fun()) {
-      return handle(context.rab_gsab_bigint64_array_map(), isolate);
+    int ctor_index =
+        TypedArrayElementsKindToConstructorIndex(map->elements_kind());
+    if (*new_target == context.get(ctor_index)) {
+      ctor_index =
+          TypedArrayElementsKindToRabGsabCtorIndex(map->elements_kind());
+      return handle(Map::cast(context.get(ctor_index)), isolate);
     }
   }
 
   // This only happens when subclassing TypedArrays. Create a new map with the
   // corresponding RAB / GSAB ElementsKind. Note: the map is not cached and
   // reused -> every array gets a unique map, making ICs slow.
-  Handle<Map> map =
-      GetDerivedMap(isolate, constructor, new_target).ToHandleChecked();
   Handle<Map> rab_gsab_map = Map::Copy(isolate, map, "RAB / GSAB");
   rab_gsab_map->set_elements_kind(
       GetCorrespondingRabGsabElementsKind(map->elements_kind()));