[vm,corelib] Change static type of _Hash*Base._data to match runtime type

VM uses _List<dynamic> for _HashVMBase._data, _HashVMImmutableBase._data
and _uninitializedData at run time.

Core library declares _data as List<Object?> and sometimes sets
it to List<Object?>.

This discrepancy between runtime type and static type sometimes
causes performance regressions, because speculative exactness guard
checks if runtime type arguments are exactly the same as type
arguments of a static type, and deoptimization is triggered
if they don't match.

Since https://dart-review.googlesource.com/c/sdk/+/440064,
VM evaluates type arguments of _HashVMBase._data and
 _HashVMImmutableBase._data as <dynamic> at compile time, so
exactness guard against _data fails more often, which considerably
affects performance in JIT mode.

This change aligns runtime and static types of _data, making
sure exactness guard against _data is always successful.

TEST=ci, golem

Change-Id: Ia842b57a372305001b5210ca59206992611c5fa7
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/440681
Reviewed-by: Ryan Macnak <[email protected]>
Commit-Queue: Alexander Markov <[email protected]>

Author: alexmarkov

runtime/vm/compiler/recognized_methods_list.h

@@ -80,9 +80,9 @@ namespace dart {
   V(CompactHashLibrary, _HashVMBase, set:_index, LinkedHashBase_setIndex,      \
     0xcf36944c)                                                                \
   V(CompactHashLibrary, _HashVMBase, get:_data, LinkedHashBase_getData,        \
-    0x372bf7ad)                                                                \
+    0x82aeadd7)                                                                \
   V(CompactHashLibrary, _HashVMBase, set:_data, LinkedHashBase_setData,        \
-    0x4b9888e9)                                                                \
+    0xc1465c93)                                                                \
   V(CompactHashLibrary, _HashVMBase, get:_usedData,                            \
     LinkedHashBase_getUsedData, 0x74808f38)                                    \
   V(CompactHashLibrary, _HashVMBase, set:_usedData,                            \
@@ -96,15 +96,15 @@ namespace dart {
   V(CompactHashLibrary, _HashVMBase, set:_deletedKeys,                         \
     LinkedHashBase_setDeletedKeys, 0xe2aeac51)                                 \
   V(CompactHashLibrary, _HashVMImmutableBase, get:_data,                       \
-    ImmutableLinkedHashBase_getData, 0x372bf7ad)                               \
+    ImmutableLinkedHashBase_getData, 0x82aeadd7)                               \
   V(CompactHashLibrary, _HashVMImmutableBase, get:_indexNullable,              \
     ImmutableLinkedHashBase_getIndex, 0xfe7649ae)                              \
   V(CompactHashLibrary, _HashVMImmutableBase, set:_index,                      \
     ImmutableLinkedHashBase_setIndexStoreRelease, 0xcf36944c)                  \
   V(CompactHashLibrary, ::, get:_uninitializedIndex,                           \
     CompactHash_uninitializedIndex, 0xa25a79e6)                                \
   V(CompactHashLibrary, ::, get:_uninitializedData,                            \
-    CompactHash_uninitializedData, 0x06a56b3b)                                 \
+    CompactHash_uninitializedData, 0x52282165)                                 \
   V(DeveloperLibrary, ::, get:extensionStreamHasListener,                      \
     ExtensionStreamHasListener, 0xfa975305)                                    \
   V(DeveloperLibrary, ::, debugger, Debugger, 0xf0aaff14)                      \

sdk/lib/_internal/vm_shared/lib/compact_hash.dart

@@ -115,7 +115,7 @@ abstract class _HashAbstractBase {
 
   abstract int _hashMask;
 
-  abstract List<Object?> _data;
+  abstract List _data;
 
   abstract int _usedData;
 
@@ -151,7 +151,7 @@ abstract class _HashFieldBase implements _HashAbstractImmutableBase {
   // Fixed-length list of keys (set) or key/value at even/odd indices (map).
   //
   // Can be either a mutable or immutable list.
-  List<Object?> _data = _uninitializedData;
+  List _data = _uninitializedData;
 
   // Length of _data that is used (i.e., keys + values for a map).
   int _usedData = 0;
@@ -186,10 +186,10 @@ abstract class _HashVMBase implements _HashAbstractBase {
   @pragma("vm:recognized", "other")
   @pragma("vm:exact-result-type", "dart:core#_List")
   @pragma("vm:prefer-inline")
-  external List<Object?> get _data;
+  external List get _data;
   @pragma("vm:recognized", "other")
   @pragma("vm:prefer-inline")
-  external void set _data(List<Object?> value);
+  external void set _data(List value);
 
   @pragma("vm:recognized", "other")
   @pragma("vm:exact-result-type", "dart:core#_Smi")
@@ -215,7 +215,7 @@ abstract class _HashVMImmutableBase extends _HashVMBase
   @pragma("vm:recognized", "other")
   @pragma("vm:exact-result-type", "dart:core#_ImmutableList")
   @pragma("vm:prefer-inline")
-  external List<Object?> get _data;
+  external List get _data;
 
   // The index is nullable rather than not nullable.
   @pragma("vm:recognized", "other")
@@ -282,16 +282,16 @@ mixin _HashBase on _HashAbstractBase {
   static int _nextProbe(int i, int sizeMask) => (i + 1) & sizeMask;
 
   // A self-loop is used to mark a deleted key or value.
-  static bool _isDeleted(List<Object?> data, Object? keyOrValue) =>
+  static bool _isDeleted(List data, Object? keyOrValue) =>
       identical(keyOrValue, data);
-  static void _setDeletedAt(List<Object?> data, int d) {
+  static void _setDeletedAt(List data, int d) {
     data[d] = data;
   }
 
   // Concurrent modification detection relies on this checksum monotonically
   // increasing between reallocations of _data.
   int get _checkSum => _usedData + _deletedKeys;
-  bool _isModifiedSince(List<Object?> oldData, int oldCheckSum) =>
+  bool _isModifiedSince(List oldData, int oldCheckSum) =>
       !identical(_data, oldData) || (_checkSum != oldCheckSum);
 
   int get length;
@@ -311,7 +311,7 @@ mixin _HashBase on _HashAbstractBase {
     assert(!identical(other._data, _uninitializedData));
     _index = Uint32List.fromList(other._index);
     _hashMask = other._hashMask;
-    _data = List<Object?>.of(other._data, growable: false);
+    _data = List.of(other._data, growable: false);
     _usedData = other._usedData;
     _deletedKeys = other._deletedKeys;
     return true;
@@ -371,7 +371,7 @@ external Uint32List get _uninitializedIndex;
 @pragma("vm:prefer-inline")
 @pragma("vm:recognized", "other")
 @pragma("vm:exact-result-type", "dart:core#_List")
-external List<Object?> get _uninitializedData;
+external List get _uninitializedData;
 
 // VM-internalized implementation of a default-constructed LinkedHashMap. Map
 // literals also create instances of this class.
@@ -546,7 +546,7 @@ mixin _LinkedHashMapMixin<K, V> on _HashBase, _EqualsAndHashCode {
   /// This function is unsafe: it does not perform any type checking on
   /// keys and values assuming that caller has ensured that types are
   /// correct.
-  void _populateUnsafe(List<Object?> keyValuePairs) {
+  void _populateUnsafe(List keyValuePairs) {
     assert(keyValuePairs.length.isEven);
     int size = _roundUpToPowerOfTwo(keyValuePairs.length);
     if (size < _HashBase._INITIAL_INDEX_SIZE) {
@@ -1338,5 +1338,5 @@ typedef DefaultMap<K, V> = _Map<K, V>;
 typedef DefaultSet<E> = _Set<E>;
 
 @pragma('vm:prefer-inline')
-Map<K, V> createMapFromKeyValueListUnsafe<K, V>(List<Object?> keyValuePairs) =>
+Map<K, V> createMapFromKeyValueListUnsafe<K, V>(List keyValuePairs) =>
     DefaultMap<K, V>().._populateUnsafe(keyValuePairs);