[turbofan] Utilize maps from field type tracking to eliminate map checks.

src/compiler/access-builder.cc

 // Copyright 2014 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/compiler/access-builder.h"
 
 #include "src/compiler/type-cache.h"
 #include "src/contexts.h"
 #include "src/frames.h"
 #include "src/handles-inl.h"
 #include "src/heap/heap.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 // static
 FieldAccess AccessBuilder::ForExternalDoubleValue() {
-  FieldAccess access = {kUntaggedBase,          0,
-                        MaybeHandle<Name>(),    Type::Number(),
-                        MachineType::Float64(), kNoWriteBarrier};
+  FieldAccess access = {kUntaggedBase,       0,
+                        MaybeHandle<Name>(), MaybeHandle<Map>(),
+                        Type::Number(),      MachineType::Float64(),
+                        kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForExternalUint8Value() {
-  FieldAccess access = {kUntaggedBase,        0,
-                        MaybeHandle<Name>(),  TypeCache::Get().kUint8,
-                        MachineType::Uint8(), kNoWriteBarrier};
+  FieldAccess access = {kUntaggedBase,           0,
+                        MaybeHandle<Name>(),     MaybeHandle<Map>(),
+                        TypeCache::Get().kUint8, MachineType::Uint8(),
+                        kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForMap() {
-  FieldAccess access = {
-      kTaggedBase,           HeapObject::kMapOffset,       MaybeHandle<Name>(),
-      Type::OtherInternal(), MachineType::TaggedPointer(), kMapWriteBarrier};
+  FieldAccess access = {kTaggedBase,           HeapObject::kMapOffset,
+                        MaybeHandle<Name>(),   MaybeHandle<Map>(),
+                        Type::OtherInternal(), MachineType::TaggedPointer(),
+                        kMapWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForHeapNumberValue() {
-  FieldAccess access = {kTaggedBase,
-                        HeapNumber::kValueOffset,
-                        MaybeHandle<Name>(),
-                        TypeCache::Get().kFloat64,
-                        MachineType::Float64(),
-                        kNoWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,        HeapNumber::kValueOffset,  MaybeHandle<Name>(),
+      MaybeHandle<Map>(), TypeCache::Get().kFloat64, MachineType::Float64(),
+      kNoWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForJSObjectProperties() {
-  FieldAccess access = {
-      kTaggedBase,      JSObject::kPropertiesOffset,  MaybeHandle<Name>(),
-      Type::Internal(), MachineType::TaggedPointer(), kPointerWriteBarrier};
+  FieldAccess access = {kTaggedBase,         JSObject::kPropertiesOffset,
+                        MaybeHandle<Name>(), MaybeHandle<Map>(),
+                        Type::Internal(),    MachineType::TaggedPointer(),
+                        kPointerWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForJSObjectElements() {
-  FieldAccess access = {
-      kTaggedBase,      JSObject::kElementsOffset,    MaybeHandle<Name>(),
-      Type::Internal(), MachineType::TaggedPointer(), kPointerWriteBarrier};
+  FieldAccess access = {kTaggedBase,         JSObject::kElementsOffset,
+                        MaybeHandle<Name>(), MaybeHandle<Map>(),
+                        Type::Internal(),    MachineType::TaggedPointer(),
+                        kPointerWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForJSObjectInObjectProperty(Handle<Map> map,
                                                        int index) {
   int const offset = map->GetInObjectPropertyOffset(index);
-  FieldAccess access = {kTaggedBase,
-                        offset,
-                        MaybeHandle<Name>(),
-                        Type::NonInternal(),
-                        MachineType::AnyTagged(),
+  FieldAccess access = {kTaggedBase,         offset,
+                        MaybeHandle<Name>(), MaybeHandle<Map>(),
+                        Type::NonInternal(), MachineType::AnyTagged(),
                         kFullWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForJSFunctionPrototypeOrInitialMap() {
-  FieldAccess access = {kTaggedBase,
-                        JSFunction::kPrototypeOrInitialMapOffset,
-                        MaybeHandle<Name>(),
-                        Type::Any(),
-                        MachineType::AnyTagged(),
-                        kFullWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,         JSFunction::kPrototypeOrInitialMapOffset,
+      MaybeHandle<Name>(), MaybeHandle<Map>(),
+      Type::Any(),         MachineType::AnyTagged(),
+      kFullWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSFunctionContext() {
-  FieldAccess access = {
-      kTaggedBase,      JSFunction::kContextOffset, MaybeHandle<Name>(),
-      Type::Internal(), MachineType::AnyTagged(),   kPointerWriteBarrier};
+  FieldAccess access = {kTaggedBase,         JSFunction::kContextOffset,
+                        MaybeHandle<Name>(), MaybeHandle<Map>(),
+                        Type::Internal(),    MachineType::AnyTagged(),
+                        kPointerWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForJSFunctionSharedFunctionInfo() {
-  FieldAccess access = {kTaggedBase,
-                        JSFunction::kSharedFunctionInfoOffset,
-                        Handle<Name>(),
-                        Type::OtherInternal(),
-                        MachineType::TaggedPointer(),
+  FieldAccess access = {
+      kTaggedBase,           JSFunction::kSharedFunctionInfoOffset,
+      Handle<Name>(),        MaybeHandle<Map>(),
+      Type::OtherInternal(), MachineType::TaggedPointer(),
+      kPointerWriteBarrier};
+  return access;
+}
+
+// static
+FieldAccess AccessBuilder::ForJSFunctionLiterals() {
+  FieldAccess access = {kTaggedBase,         JSFunction::kLiteralsOffset,
+                        Handle<Name>(),      MaybeHandle<Map>(),
+                        Type::Internal(),    MachineType::TaggedPointer(),
                         kPointerWriteBarrier};
   return access;
 }
 
 // static
-FieldAccess AccessBuilder::ForJSFunctionLiterals() {
-  FieldAccess access = {
-      kTaggedBase,      JSFunction::kLiteralsOffset,  Handle<Name>(),
-      Type::Internal(), MachineType::TaggedPointer(), kPointerWriteBarrier};
-  return access;
-}
-
-// static
 FieldAccess AccessBuilder::ForJSFunctionCodeEntry() {
-  FieldAccess access = {
-      kTaggedBase,           JSFunction::kCodeEntryOffset, Handle<Name>(),
-      Type::OtherInternal(), MachineType::Pointer(),       kNoWriteBarrier};
+  FieldAccess access = {kTaggedBase,           JSFunction::kCodeEntryOffset,
+                        Handle<Name>(),        MaybeHandle<Map>(),
+                        Type::OtherInternal(), MachineType::Pointer(),
+                        kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSFunctionNextFunctionLink() {
-  FieldAccess access = {kTaggedBase,
-                        JSFunction::kNextFunctionLinkOffset,
-                        Handle<Name>(),
-                        Type::Any(),
-                        MachineType::AnyTagged(),
-                        kPointerWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,         JSFunction::kNextFunctionLinkOffset,
+      Handle<Name>(),      MaybeHandle<Map>(),
+      Type::Any(),         MachineType::AnyTagged(),
+      kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSGeneratorObjectContext() {
-  FieldAccess access = {kTaggedBase,
-                        JSGeneratorObject::kContextOffset,
-                        Handle<Name>(),
-                        Type::Internal(),
-                        MachineType::TaggedPointer(),
+  FieldAccess access = {kTaggedBase,         JSGeneratorObject::kContextOffset,
+                        Handle<Name>(),      MaybeHandle<Map>(),
+                        Type::Internal(),    MachineType::TaggedPointer(),
                         kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSGeneratorObjectContinuation() {
-  FieldAccess access = {kTaggedBase,
-                        JSGeneratorObject::kContinuationOffset,
-                        Handle<Name>(),
-                        Type::SignedSmall(),
-                        MachineType::TaggedSigned(),
-                        kNoWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,         JSGeneratorObject::kContinuationOffset,
+      Handle<Name>(),      MaybeHandle<Map>(),
+      Type::SignedSmall(), MachineType::TaggedSigned(),
+      kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSGeneratorObjectInputOrDebugPos() {
-  FieldAccess access = {kTaggedBase,
-                        JSGeneratorObject::kInputOrDebugPosOffset,
-                        Handle<Name>(),
-                        Type::NonInternal(),
-                        MachineType::AnyTagged(),
-                        kFullWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,         JSGeneratorObject::kInputOrDebugPosOffset,
+      Handle<Name>(),      MaybeHandle<Map>(),
+      Type::NonInternal(), MachineType::AnyTagged(),
+      kFullWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSGeneratorObjectRegisterFile() {
-  FieldAccess access = {kTaggedBase,
-                        JSGeneratorObject::kRegisterFileOffset,
-                        Handle<Name>(),
-                        Type::Internal(),
-                        MachineType::AnyTagged(),
-                        kPointerWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,         JSGeneratorObject::kRegisterFileOffset,
+      Handle<Name>(),      MaybeHandle<Map>(),
+      Type::Internal(),    MachineType::AnyTagged(),
+      kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSGeneratorObjectResumeMode() {
-  FieldAccess access = {kTaggedBase,
-                        JSGeneratorObject::kResumeModeOffset,
-                        Handle<Name>(),
-                        Type::SignedSmall(),
-                        MachineType::TaggedSigned(),
-                        kNoWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,         JSGeneratorObject::kResumeModeOffset,
+      Handle<Name>(),      MaybeHandle<Map>(),
+      Type::SignedSmall(), MachineType::TaggedSigned(),
+      kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSArrayLength(ElementsKind elements_kind) {
   TypeCache const& type_cache = TypeCache::Get();
   FieldAccess access = {kTaggedBase,
                         JSArray::kLengthOffset,
                         Handle<Name>(),
+                        MaybeHandle<Map>(),
                         type_cache.kJSArrayLengthType,
                         MachineType::TaggedSigned(),
                         kFullWriteBarrier};
   if (IsFastDoubleElementsKind(elements_kind)) {
     access.type = type_cache.kFixedDoubleArrayLengthType;
     access.write_barrier_kind = kNoWriteBarrier;
   } else if (IsFastElementsKind(elements_kind)) {
     access.type = type_cache.kFixedArrayLengthType;
     access.write_barrier_kind = kNoWriteBarrier;
   }
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForJSArrayBufferBackingStore() {
-  FieldAccess access = {kTaggedBase,
-                        JSArrayBuffer::kBackingStoreOffset,
-                        MaybeHandle<Name>(),
-                        Type::OtherInternal(),
-                        MachineType::Pointer(),
-                        kNoWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,           JSArrayBuffer::kBackingStoreOffset,
+      MaybeHandle<Name>(),   MaybeHandle<Map>(),
+      Type::OtherInternal(), MachineType::Pointer(),
+      kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSArrayBufferBitField() {
-  FieldAccess access = {kTaggedBase,           JSArrayBuffer::kBitFieldOffset,
-                        MaybeHandle<Name>(),   TypeCache::Get().kUint8,
-                        MachineType::Uint32(), kNoWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,        JSArrayBuffer::kBitFieldOffset, MaybeHandle<Name>(),
+      MaybeHandle<Map>(), TypeCache::Get().kUint8,        MachineType::Uint32(),
+      kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSArrayBufferViewBuffer() {
-  FieldAccess access = {kTaggedBase,
-                        JSArrayBufferView::kBufferOffset,
-                        MaybeHandle<Name>(),
-                        Type::OtherInternal(),
-                        MachineType::TaggedPointer(),
+  FieldAccess access = {kTaggedBase,           JSArrayBufferView::kBufferOffset,
+                        MaybeHandle<Name>(),   MaybeHandle<Map>(),
+                        Type::OtherInternal(), MachineType::TaggedPointer(),
                         kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSArrayBufferViewByteLength() {
   FieldAccess access = {kTaggedBase,
                         JSArrayBufferView::kByteLengthOffset,
                         MaybeHandle<Name>(),
+                        MaybeHandle<Map>(),
                         TypeCache::Get().kPositiveInteger,
                         MachineType::AnyTagged(),
                         kFullWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSArrayBufferViewByteOffset() {
   FieldAccess access = {kTaggedBase,
                         JSArrayBufferView::kByteOffsetOffset,
                         MaybeHandle<Name>(),
+                        MaybeHandle<Map>(),
                         TypeCache::Get().kPositiveInteger,
                         MachineType::AnyTagged(),
                         kFullWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSTypedArrayLength() {
   FieldAccess access = {kTaggedBase,
                         JSTypedArray::kLengthOffset,
                         MaybeHandle<Name>(),
+                        MaybeHandle<Map>(),
                         TypeCache::Get().kJSTypedArrayLengthType,
                         MachineType::TaggedSigned(),
                         kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSDateValue() {
   FieldAccess access = {kTaggedBase,
                         JSDate::kValueOffset,
                         MaybeHandle<Name>(),
+                        MaybeHandle<Map>(),
                         TypeCache::Get().kJSDateValueType,
                         MachineType::AnyTagged(),
                         kFullWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSDateField(JSDate::FieldIndex index) {
-  FieldAccess access = {kTaggedBase,
-                        JSDate::kValueOffset + index * kPointerSize,
-                        MaybeHandle<Name>(),
-                        Type::Number(),
-                        MachineType::AnyTagged(),
+  FieldAccess access = {
+      kTaggedBase,         JSDate::kValueOffset + index * kPointerSize,
+      MaybeHandle<Name>(), MaybeHandle<Map>(),
+      Type::Number(),      MachineType::AnyTagged(),
+      kFullWriteBarrier};
+  return access;
+}
+
+
+// static
+FieldAccess AccessBuilder::ForJSIteratorResultDone() {
+  FieldAccess access = {kTaggedBase,         JSIteratorResult::kDoneOffset,
+                        MaybeHandle<Name>(), MaybeHandle<Map>(),
+                        Type::NonInternal(), MachineType::AnyTagged(),
                         kFullWriteBarrier};
   return access;
 }
 
 
 // static
-FieldAccess AccessBuilder::ForJSIteratorResultDone() {
-  FieldAccess access = {
-      kTaggedBase,         JSIteratorResult::kDoneOffset, MaybeHandle<Name>(),
-      Type::NonInternal(), MachineType::AnyTagged(),      kFullWriteBarrier};
-  return access;
-}
-
-
-// static
 FieldAccess AccessBuilder::ForJSIteratorResultValue() {
-  FieldAccess access = {
-      kTaggedBase,         JSIteratorResult::kValueOffset, MaybeHandle<Name>(),
-      Type::NonInternal(), MachineType::AnyTagged(),       kFullWriteBarrier};
+  FieldAccess access = {kTaggedBase,         JSIteratorResult::kValueOffset,
+                        MaybeHandle<Name>(), MaybeHandle<Map>(),
+                        Type::NonInternal(), MachineType::AnyTagged(),
+                        kFullWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForJSRegExpFlags() {
-  FieldAccess access = {
-      kTaggedBase,         JSRegExp::kFlagsOffset,   MaybeHandle<Name>(),
-      Type::NonInternal(), MachineType::AnyTagged(), kFullWriteBarrier};
+  FieldAccess access = {kTaggedBase,         JSRegExp::kFlagsOffset,
+                        MaybeHandle<Name>(), MaybeHandle<Map>(),
+                        Type::NonInternal(), MachineType::AnyTagged(),
+                        kFullWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForJSRegExpSource() {
-  FieldAccess access = {
-      kTaggedBase,         JSRegExp::kSourceOffset,  MaybeHandle<Name>(),
-      Type::NonInternal(), MachineType::AnyTagged(), kFullWriteBarrier};
+  FieldAccess access = {kTaggedBase,         JSRegExp::kSourceOffset,
+                        MaybeHandle<Name>(), MaybeHandle<Map>(),
+                        Type::NonInternal(), MachineType::AnyTagged(),
+                        kFullWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForFixedArrayLength() {
   FieldAccess access = {kTaggedBase,
                         FixedArray::kLengthOffset,
                         MaybeHandle<Name>(),
+                        MaybeHandle<Map>(),
                         TypeCache::Get().kFixedArrayLengthType,
                         MachineType::TaggedSigned(),
                         kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForFixedTypedArrayBaseBasePointer() {
-  FieldAccess access = {kTaggedBase,
-                        FixedTypedArrayBase::kBasePointerOffset,
-                        MaybeHandle<Name>(),
-                        Type::OtherInternal(),
-                        MachineType::AnyTagged(),
-                        kPointerWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,           FixedTypedArrayBase::kBasePointerOffset,
+      MaybeHandle<Name>(),   MaybeHandle<Map>(),
+      Type::OtherInternal(), MachineType::AnyTagged(),
+      kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForFixedTypedArrayBaseExternalPointer() {
   FieldAccess access = {kTaggedBase,
                         FixedTypedArrayBase::kExternalPointerOffset,
                         MaybeHandle<Name>(),
+                        MaybeHandle<Map>(),
                         Type::ExternalPointer(),
                         MachineType::Pointer(),
                         kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForDescriptorArrayEnumCache() {
-  FieldAccess access = {kTaggedBase,
-                        DescriptorArray::kEnumCacheOffset,
-                        Handle<Name>(),
-                        Type::OtherInternal(),
-                        MachineType::TaggedPointer(),
-                        kPointerWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,           DescriptorArray::kEnumCacheOffset,
+      Handle<Name>(),        MaybeHandle<Map>(),
+      Type::OtherInternal(), MachineType::TaggedPointer(),
+      kPointerWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForDescriptorArrayEnumCacheBridgeCache() {
-  FieldAccess access = {kTaggedBase,
-                        DescriptorArray::kEnumCacheBridgeCacheOffset,
-                        Handle<Name>(),
-                        Type::OtherInternal(),
-                        MachineType::TaggedPointer(),
-                        kPointerWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,           DescriptorArray::kEnumCacheBridgeCacheOffset,
+      Handle<Name>(),        MaybeHandle<Map>(),
+      Type::OtherInternal(), MachineType::TaggedPointer(),
+      kPointerWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForMapBitField() {
-  FieldAccess access = {kTaggedBase,          Map::kBitFieldOffset,
-                        Handle<Name>(),       TypeCache::Get().kUint8,
-                        MachineType::Uint8(), kNoWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,        Map::kBitFieldOffset,    Handle<Name>(),
+      MaybeHandle<Map>(), TypeCache::Get().kUint8, MachineType::Uint8(),
+      kNoWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForMapBitField3() {
-  FieldAccess access = {kTaggedBase,          Map::kBitField3Offset,
-                        Handle<Name>(),       TypeCache::Get().kInt32,
-                        MachineType::Int32(), kNoWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,        Map::kBitField3Offset,   Handle<Name>(),
+      MaybeHandle<Map>(), TypeCache::Get().kInt32, MachineType::Int32(),
+      kNoWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForMapDescriptors() {
-  FieldAccess access = {kTaggedBase,
-                        Map::kDescriptorsOffset,
-                        Handle<Name>(),
-                        Type::OtherInternal(),
-                        MachineType::TaggedPointer(),
+  FieldAccess access = {kTaggedBase,           Map::kDescriptorsOffset,
+                        Handle<Name>(),        MaybeHandle<Map>(),
+                        Type::OtherInternal(), MachineType::TaggedPointer(),
                         kPointerWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForMapInstanceType() {
-  FieldAccess access = {kTaggedBase,          Map::kInstanceTypeOffset,
-                        Handle<Name>(),       TypeCache::Get().kUint8,
-                        MachineType::Uint8(), kNoWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,        Map::kInstanceTypeOffset, Handle<Name>(),
+      MaybeHandle<Map>(), TypeCache::Get().kUint8,  MachineType::Uint8(),
+      kNoWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForMapPrototype() {
-  FieldAccess access = {
-      kTaggedBase, Map::kPrototypeOffset,        Handle<Name>(),
-      Type::Any(), MachineType::TaggedPointer(), kPointerWriteBarrier};
+  FieldAccess access = {kTaggedBase,         Map::kPrototypeOffset,
+                        Handle<Name>(),      MaybeHandle<Map>(),
+                        Type::Any(),         MachineType::TaggedPointer(),
+                        kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForModuleRegularExports() {
-  FieldAccess access = {kTaggedBase,
-                        Module::kRegularExportsOffset,
-                        Handle<Name>(),
-                        Type::OtherInternal(),
-                        MachineType::TaggedPointer(),
+  FieldAccess access = {kTaggedBase,           Module::kRegularExportsOffset,
+                        Handle<Name>(),        MaybeHandle<Map>(),
+                        Type::OtherInternal(), MachineType::TaggedPointer(),
                         kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForModuleRegularImports() {
-  FieldAccess access = {kTaggedBase,
-                        Module::kRegularImportsOffset,
-                        Handle<Name>(),
-                        Type::OtherInternal(),
-                        MachineType::TaggedPointer(),
+  FieldAccess access = {kTaggedBase,           Module::kRegularImportsOffset,
+                        Handle<Name>(),        MaybeHandle<Map>(),
+                        Type::OtherInternal(), MachineType::TaggedPointer(),
                         kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForNameHashField() {
-  FieldAccess access = {kTaggedBase,           Name::kHashFieldOffset,
-                        Handle<Name>(),        Type::Internal(),
-                        MachineType::Uint32(), kNoWriteBarrier};
+  FieldAccess access = {kTaggedBase,      Name::kHashFieldOffset,
+                        Handle<Name>(),   MaybeHandle<Map>(),
+                        Type::Internal(), MachineType::Uint32(),
+                        kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForStringLength() {
   FieldAccess access = {kTaggedBase,
                         String::kLengthOffset,
                         Handle<Name>(),
+                        MaybeHandle<Map>(),
                         TypeCache::Get().kStringLengthType,
                         MachineType::TaggedSigned(),
                         kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForConsStringFirst() {
-  FieldAccess access = {
-      kTaggedBase,    ConsString::kFirstOffset,     Handle<Name>(),
-      Type::String(), MachineType::TaggedPointer(), kPointerWriteBarrier};
+  FieldAccess access = {kTaggedBase,         ConsString::kFirstOffset,
+                        Handle<Name>(),      MaybeHandle<Map>(),
+                        Type::String(),      MachineType::TaggedPointer(),
+                        kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForConsStringSecond() {
-  FieldAccess access = {
-      kTaggedBase,    ConsString::kSecondOffset,    Handle<Name>(),
-      Type::String(), MachineType::TaggedPointer(), kPointerWriteBarrier};
+  FieldAccess access = {kTaggedBase,         ConsString::kSecondOffset,
+                        Handle<Name>(),      MaybeHandle<Map>(),
+                        Type::String(),      MachineType::TaggedPointer(),
+                        kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForSlicedStringOffset() {
-  FieldAccess access = {
-      kTaggedBase,         SlicedString::kOffsetOffset, Handle<Name>(),
-      Type::SignedSmall(), MachineType::TaggedSigned(), kNoWriteBarrier};
+  FieldAccess access = {kTaggedBase,         SlicedString::kOffsetOffset,
+                        Handle<Name>(),      MaybeHandle<Map>(),
+                        Type::SignedSmall(), MachineType::TaggedSigned(),
+                        kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForSlicedStringParent() {
-  FieldAccess access = {
-      kTaggedBase,    SlicedString::kParentOffset,  Handle<Name>(),
-      Type::String(), MachineType::TaggedPointer(), kPointerWriteBarrier};
+  FieldAccess access = {kTaggedBase,         SlicedString::kParentOffset,
+                        Handle<Name>(),      MaybeHandle<Map>(),
+                        Type::String(),      MachineType::TaggedPointer(),
+                        kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForExternalStringResourceData() {
   FieldAccess access = {kTaggedBase,
                         ExternalString::kResourceDataOffset,
                         Handle<Name>(),
+                        MaybeHandle<Map>(),
                         Type::ExternalPointer(),
                         MachineType::Pointer(),
                         kNoWriteBarrier};
   return access;
 }
 
 // static
 ElementAccess AccessBuilder::ForExternalOneByteStringCharacter() {
   ElementAccess access = {kUntaggedBase, 0, TypeCache::Get().kUint8,
                           MachineType::Uint8(), kNoWriteBarrier};
@@ skipping 18 matching lines @@
 // static
 ElementAccess AccessBuilder::ForSeqTwoByteStringCharacter() {
   ElementAccess access = {kTaggedBase, SeqTwoByteString::kHeaderSize,
                           TypeCache::Get().kUint16, MachineType::Uint16(),
                           kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSGlobalObjectGlobalProxy() {
-  FieldAccess access = {kTaggedBase,
-                        JSGlobalObject::kGlobalProxyOffset,
-                        Handle<Name>(),
-                        Type::Receiver(),
-                        MachineType::TaggedPointer(),
+  FieldAccess access = {kTaggedBase,         JSGlobalObject::kGlobalProxyOffset,
+                        Handle<Name>(),      MaybeHandle<Map>(),
+                        Type::Receiver(),    MachineType::TaggedPointer(),
                         kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSGlobalObjectNativeContext() {
-  FieldAccess access = {kTaggedBase,
-                        JSGlobalObject::kNativeContextOffset,
-                        Handle<Name>(),
-                        Type::Internal(),
-                        MachineType::TaggedPointer(),
-                        kPointerWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,         JSGlobalObject::kNativeContextOffset,
+      Handle<Name>(),      MaybeHandle<Map>(),
+      Type::Internal(),    MachineType::TaggedPointer(),
+      kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSArrayIteratorObject() {
   FieldAccess access = {kTaggedBase,
                         JSArrayIterator::kIteratedObjectOffset,
                         Handle<Name>(),
+                        MaybeHandle<Map>(),
                         Type::ReceiverOrUndefined(),
                         MachineType::TaggedPointer(),
                         kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSArrayIteratorIndex(InstanceType instance_type,
                                                    ElementsKind elements_kind) {
   // In generic case, cap to 2^53-1 (per ToLength() in spec) via
   // kPositiveSafeInteger
   FieldAccess access = {kTaggedBase,
                         JSArrayIterator::kNextIndexOffset,
                         Handle<Name>(),
+                        MaybeHandle<Map>(),
                         TypeCache::Get().kPositiveSafeInteger,
                         MachineType::AnyTagged(),
                         kFullWriteBarrier};
   if (instance_type == JS_ARRAY_TYPE) {
     if (IsFastDoubleElementsKind(elements_kind)) {
       access.type = TypeCache::Get().kFixedDoubleArrayLengthType;
       access.machine_type = MachineType::TaggedSigned();
       access.write_barrier_kind = kNoWriteBarrier;
     } else if (IsFastElementsKind(elements_kind)) {
       access.type = TypeCache::Get().kFixedArrayLengthType;
       access.machine_type = MachineType::TaggedSigned();
       access.write_barrier_kind = kNoWriteBarrier;
     } else {
       access.type = TypeCache::Get().kJSArrayLengthType;
     }
   } else if (instance_type == JS_TYPED_ARRAY_TYPE) {
     access.type = TypeCache::Get().kJSTypedArrayLengthType;
     access.machine_type = MachineType::TaggedSigned();
     access.write_barrier_kind = kNoWriteBarrier;
   }
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSArrayIteratorObjectMap() {
-  FieldAccess access = {kTaggedBase,
-                        JSArrayIterator::kIteratedObjectMapOffset,
-                        Handle<Name>(),
-                        Type::OtherInternal(),
-                        MachineType::TaggedPointer(),
-                        kPointerWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,           JSArrayIterator::kIteratedObjectMapOffset,
+      Handle<Name>(),        MaybeHandle<Map>(),
+      Type::OtherInternal(), MachineType::TaggedPointer(),
+      kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSStringIteratorString() {
-  FieldAccess access = {
-      kTaggedBase,    JSStringIterator::kStringOffset, Handle<Name>(),
-      Type::String(), MachineType::TaggedPointer(),    kPointerWriteBarrier};
+  FieldAccess access = {kTaggedBase,         JSStringIterator::kStringOffset,
+                        Handle<Name>(),      MaybeHandle<Map>(),
+                        Type::String(),      MachineType::TaggedPointer(),
+                        kPointerWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForJSStringIteratorIndex() {
   FieldAccess access = {kTaggedBase,
                         JSStringIterator::kNextIndexOffset,
                         Handle<Name>(),
+                        MaybeHandle<Map>(),
                         TypeCache::Get().kStringLengthType,
                         MachineType::TaggedSigned(),
                         kNoWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForValue() {
-  FieldAccess access = {
-      kTaggedBase,         JSValue::kValueOffset,    Handle<Name>(),
-      Type::NonInternal(), MachineType::AnyTagged(), kFullWriteBarrier};
+  FieldAccess access = {kTaggedBase,         JSValue::kValueOffset,
+                        Handle<Name>(),      MaybeHandle<Map>(),
+                        Type::NonInternal(), MachineType::AnyTagged(),
+                        kFullWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForArgumentsLength() {
-  FieldAccess access = {
-      kTaggedBase,         JSArgumentsObject::kLengthOffset, Handle<Name>(),
-      Type::NonInternal(), MachineType::AnyTagged(),         kFullWriteBarrier};
+  FieldAccess access = {kTaggedBase,         JSArgumentsObject::kLengthOffset,
+                        Handle<Name>(),      MaybeHandle<Map>(),
+                        Type::NonInternal(), MachineType::AnyTagged(),
+                        kFullWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForArgumentsCallee() {
-  FieldAccess access = {kTaggedBase,
-                        JSSloppyArgumentsObject::kCalleeOffset,
-                        Handle<Name>(),
-                        Type::NonInternal(),
-                        MachineType::AnyTagged(),
-                        kPointerWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,         JSSloppyArgumentsObject::kCalleeOffset,
+      Handle<Name>(),      MaybeHandle<Map>(),
+      Type::NonInternal(), MachineType::AnyTagged(),
+      kPointerWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForFixedArraySlot(size_t index) {
   int offset = FixedArray::OffsetOfElementAt(static_cast<int>(index));
-  FieldAccess access = {kTaggedBase,
-                        offset,
-                        Handle<Name>(),
-                        Type::NonInternal(),
-                        MachineType::AnyTagged(),
+  FieldAccess access = {kTaggedBase,         offset,
+                        Handle<Name>(),      MaybeHandle<Map>(),
+                        Type::NonInternal(), MachineType::AnyTagged(),
                         kFullWriteBarrier};
   return access;
 }
 
 
 // static
 FieldAccess AccessBuilder::ForCellValue() {
-  FieldAccess access = {
-      kTaggedBase, Cell::kValueOffset,       Handle<Name>(),
-      Type::Any(), MachineType::AnyTagged(), kFullWriteBarrier};
+  FieldAccess access = {kTaggedBase,      Cell::kValueOffset,
+                        Handle<Name>(),   MaybeHandle<Map>(),
+                        Type::Any(),      MachineType::AnyTagged(),
+                        kFullWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForContextSlot(size_t index) {
   int offset = Context::kHeaderSize + static_cast<int>(index) * kPointerSize;
   DCHECK_EQ(offset,
             Context::SlotOffset(static_cast<int>(index)) + kHeapObjectTag);
-  FieldAccess access = {kTaggedBase,
-                        offset,
-                        Handle<Name>(),
-                        Type::Any(),
-                        MachineType::AnyTagged(),
+  FieldAccess access = {kTaggedBase,      offset,
+                        Handle<Name>(),   MaybeHandle<Map>(),
+                        Type::Any(),      MachineType::AnyTagged(),
                         kFullWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForContextExtensionScopeInfo() {
-  FieldAccess access = {kTaggedBase,
-                        ContextExtension::kScopeInfoOffset,
-                        Handle<Name>(),
-                        Type::OtherInternal(),
-                        MachineType::AnyTagged(),
-                        kFullWriteBarrier};
+  FieldAccess access = {
+      kTaggedBase,           ContextExtension::kScopeInfoOffset,
+      Handle<Name>(),        MaybeHandle<Map>(),
+      Type::OtherInternal(), MachineType::AnyTagged(),
+      kFullWriteBarrier};
   return access;
 }
 
 // static
 FieldAccess AccessBuilder::ForContextExtensionExtension() {
-  FieldAccess access = {
-      kTaggedBase, ContextExtension::kExtensionOffset, Handle<Name>(),
-      Type::Any(), MachineType::AnyTagged(),           kFullWriteBarrier};
+  FieldAccess access = {kTaggedBase,      ContextExtension::kExtensionOffset,
+                        Handle<Name>(),   MaybeHandle<Map>(),
+                        Type::Any(),      MachineType::AnyTagged(),
+                        kFullWriteBarrier};
   return access;
 }
 
 // static
 ElementAccess AccessBuilder::ForFixedArrayElement() {
   ElementAccess access = {kTaggedBase, FixedArray::kHeaderSize, Type::Any(),
                           MachineType::AnyTagged(), kFullWriteBarrier};
   return access;
 }
 
@@ skipping 91 matching lines @@
   }
   UNREACHABLE();
   ElementAccess access = {kUntaggedBase, 0, Type::None(), MachineType::None(),
                           kNoWriteBarrier};
   return access;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8