[objects] Fix -Wshadow warnings

Bug: v8:12244,v8:12245
Change-Id: I1ec0d96b645afa9bbda670918ce57be3698f50ef
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3265684
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77804}

src/objects/contexts.cc

@@ -218,16 +218,17 @@ Handle<Object> Context::Lookup(Handle<Context> context, Handle<String> name,
             context->global_object().native_context().script_context_table();
         VariableLookupResult r;
         if (ScriptContextTable::Lookup(isolate, script_contexts, *name, &r)) {
-          Context context = script_contexts.get_context(r.context_index);
+          Context script_context = script_contexts.get_context(r.context_index);
           if (FLAG_trace_contexts) {
             PrintF("=> found property in script context %d: %p\n",
-                   r.context_index, reinterpret_cast<void*>(context.ptr()));
+                   r.context_index,
+                   reinterpret_cast<void*>(script_context.ptr()));
           }
           *index = r.slot_index;
           *variable_mode = r.mode;
           *init_flag = r.init_flag;
           *attributes = GetAttributesForMode(r.mode);
-          return handle(context, isolate);
+          return handle(script_context, isolate);
         }
       }
 
@@ -380,9 +381,9 @@ Handle<Object> Context::Lookup(Handle<Context> context, Handle<String> name,
       // Check the original context, but do not follow its context chain.
       Object obj = context->get(WRAPPED_CONTEXT_INDEX);
       if (obj.IsContext()) {
-        Handle<Context> context(Context::cast(obj), isolate);
+        Handle<Context> wrapped_context(Context::cast(obj), isolate);
         Handle<Object> result =
-            Context::Lookup(context, name, DONT_FOLLOW_CHAINS, index,
+            Context::Lookup(wrapped_context, name, DONT_FOLLOW_CHAINS, index,
                             attributes, init_flag, variable_mode);
         if (!result.is_null()) return result;
       }

src/objects/elements.cc

@@ -2306,7 +2306,7 @@ class FastElementsAccessor : public ElementsAccessorBase<Subclass, KindTraits> {
       }
     } else {
       if (!value.IsNaN()) {
-        double search_value = value.Number();
+        double search_number = value.Number();
         if (IsDoubleElementsKind(Subclass::kind())) {
           // Search for non-NaN Number in PACKED_DOUBLE_ELEMENTS or
           // HOLEY_DOUBLE_ELEMENTS --- Skip TheHole, and trust UCOMISD or
@@ -2316,7 +2316,7 @@ class FastElementsAccessor : public ElementsAccessorBase<Subclass, KindTraits> {
 
           for (size_t k = start_from; k < length; ++k) {
             if (elements.is_the_hole(static_cast<int>(k))) continue;
-            if (elements.get_scalar(static_cast<int>(k)) == search_value) {
+            if (elements.get_scalar(static_cast<int>(k)) == search_number) {
               return Just(true);
             }
           }
@@ -2329,7 +2329,7 @@ class FastElementsAccessor : public ElementsAccessorBase<Subclass, KindTraits> {
 
           for (size_t k = start_from; k < length; ++k) {
             Object element_k = elements.get(static_cast<int>(k));
-            if (element_k.IsNumber() && element_k.Number() == search_value) {
+            if (element_k.IsNumber() && element_k.Number() == search_number) {
               return Just(true);
             }
           }

src/objects/feedback-vector.cc

@@ -95,7 +95,7 @@ Handle<FeedbackMetadata> FeedbackMetadata::New(IsolateT* isolate,
     FeedbackSlotKind kind = spec->GetKind(FeedbackSlot(i));
     int entry_size = FeedbackMetadata::GetSlotSize(kind);
     for (int j = 1; j < entry_size; j++) {
-      FeedbackSlotKind kind = spec->GetKind(FeedbackSlot(i + j));
+      kind = spec->GetKind(FeedbackSlot(i + j));
       DCHECK_EQ(FeedbackSlotKind::kInvalid, kind);
     }
     i += entry_size;

src/objects/intl-objects.cc

@@ -1582,9 +1582,6 @@ Maybe<Intl::NumberFormatDigitOptions> Intl::SetNumberFormatDigitOptions(
 
     // 15. Else If mnfd is not undefined or mxfd is not undefined, then
     if (!mnfd_obj->IsUndefined(isolate) || !mxfd_obj->IsUndefined(isolate)) {
-      Handle<String> mxfd_str = factory->maximumFractionDigits_string();
-      Handle<String> mnfd_str = factory->minimumFractionDigits_string();
-
       int specified_mnfd;
       int specified_mxfd;
 

src/objects/js-collator.cc

@@ -401,9 +401,9 @@ MaybeHandle<JSCollator> JSCollator::New(Isolate* isolate, Handle<Map> map,
   // This will need to be filtered out when creating the
   // resolvedOptions object.
   if (usage == Usage::SEARCH) {
-    UErrorCode status = U_ZERO_ERROR;
-    icu_locale.setUnicodeKeywordValue("co", "search", status);
-    DCHECK(U_SUCCESS(status));
+    UErrorCode set_status = U_ZERO_ERROR;
+    icu_locale.setUnicodeKeywordValue("co", "search", set_status);
+    DCHECK(U_SUCCESS(set_status));
   } else {
     if (collation_str != nullptr &&
         Intl::IsValidCollation(icu_locale, collation_str.get())) {

src/objects/js-date-time-format.cc

@@ -1081,7 +1081,7 @@ class CalendarCache {
         icu::GregorianCalendar::getStaticClassID()) {
       icu::GregorianCalendar* gc =
           static_cast<icu::GregorianCalendar*>(calendar.get());
-      UErrorCode status = U_ZERO_ERROR;
+      status = U_ZERO_ERROR;
       // The beginning of ECMAScript time, namely -(2**53)
       const double start_of_time = -9007199254740992;
       gc->setGregorianChange(start_of_time, status);
@@ -1726,7 +1726,6 @@ MaybeHandle<JSDateTimeFormat> JSDateTimeFormat::New(
 
   // 29. Let matcher be ? GetOption(options, "formatMatcher", "string", «
   // "basic", "best fit" », "best fit").
-  enum FormatMatcherOption { kBestFit, kBasic };
   // We implement only best fit algorithm, but still need to check
   // if the formatMatcher values are in range.
   // c. Let matcher be ? GetOption(options, "formatMatcher", "string",
@@ -1870,7 +1869,7 @@ MaybeHandle<JSDateTimeFormat> JSDateTimeFormat::New(
       if (dateTimeFormatHourCycle !=
           ToHourCycle(hc_extension_it->second.c_str())) {
         // Remove -hc- if it does not agree with what we used.
-        UErrorCode status = U_ZERO_ERROR;
+        status = U_ZERO_ERROR;
         resolved_locale.setUnicodeKeywordValue("hc", nullptr, status);
         DCHECK(U_SUCCESS(status));
       }

src/objects/lookup.cc

@@ -1132,8 +1132,8 @@ void LookupIterator::WriteDataValueToWasmObject(Handle<Object> value) {
   } else {
     // WasmArrays don't have writable properties.
     DCHECK(holder->IsWasmStruct());
-    Handle<WasmStruct> holder = GetHolder<WasmStruct>();
-    WasmStruct::SetField(isolate_, holder, property_details_.field_index(),
+    Handle<WasmStruct> wasm_holder = GetHolder<WasmStruct>();
+    WasmStruct::SetField(isolate_, wasm_holder, property_details_.field_index(),
                          value);
   }
 }

src/objects/map-updater.cc

@@ -859,7 +859,6 @@ Handle<DescriptorArray> MapUpdater::BuildDescriptorArray() {
     PropertyLocation next_location = old_details.location();
     Representation next_representation = old_details.representation();
 
-    Descriptor d;
     if (next_location == PropertyLocation::kField) {
       Handle<FieldType> next_field_type =
           GetOrComputeFieldType(i, old_details.location(), next_representation);
@@ -889,6 +888,7 @@ Handle<DescriptorArray> MapUpdater::BuildDescriptorArray() {
       DCHECK_EQ(PropertyConstness::kConst, next_constness);
 
       Handle<Object> value(GetValue(i), isolate_);
+      Descriptor d;
       if (next_kind == kData) {
         d = Descriptor::DataConstant(key, value, next_attributes);
       } else {
@@ -1121,7 +1121,7 @@ void MapUpdater::UpdateFieldType(Isolate* isolate, Handle<Map> map,
       backlog.push(target);
     }
     DescriptorArray descriptors = current.instance_descriptors(isolate);
-    PropertyDetails details = descriptors.GetDetails(descriptor);
+    details = descriptors.GetDetails(descriptor);
 
     // It is allowed to change representation here only from None
     // to something or from Smi or HeapObject to Tagged.

src/objects/objects.cc

@@ -2972,7 +2972,7 @@ Maybe<bool> JSProxy::IsArray(Handle<JSProxy> proxy) {
   Isolate* isolate = proxy->GetIsolate();
   Handle<JSReceiver> object = Handle<JSReceiver>::cast(proxy);
   for (int i = 0; i < JSProxy::kMaxIterationLimit; i++) {
-    Handle<JSProxy> proxy = Handle<JSProxy>::cast(object);
+    proxy = Handle<JSProxy>::cast(object);
     if (proxy->IsRevoked()) {
       isolate->Throw(*isolate->factory()->NewTypeError(
           MessageTemplate::kProxyRevoked,
@@ -3391,9 +3391,9 @@ Maybe<bool> JSArray::ArraySetLength(Isolate* isolate, Handle<JSArray> a,
   if (!new_writable) {
     PropertyDescriptor readonly;
     readonly.set_writable(false);
-    Maybe<bool> success = OrdinaryDefineOwnProperty(
-        isolate, a, isolate->factory()->length_string(), &readonly,
-        should_throw);
+    success = OrdinaryDefineOwnProperty(isolate, a,
+                                        isolate->factory()->length_string(),
+                                        &readonly, should_throw);
     DCHECK(success.FromJust());
     USE(success);
   }
@@ -4376,12 +4376,12 @@ void DescriptorArray::CopyFrom(InternalIndex index, DescriptorArray src) {
 
 void DescriptorArray::Sort() {
   // In-place heap sort.
-  int len = number_of_descriptors();
+  const int len = number_of_descriptors();
   // Reset sorting since the descriptor array might contain invalid pointers.
   for (int i = 0; i < len; ++i) SetSortedKey(i, i);
   // Bottom-up max-heap construction.
   // Index of the last node with children.
-  const int max_parent_index = (len / 2) - 1;
+  int max_parent_index = (len / 2) - 1;
   for (int i = max_parent_index; i >= 0; --i) {
     int parent_index = i;
     const uint32_t parent_hash = GetSortedKey(i).hash();
@@ -4409,7 +4409,7 @@ void DescriptorArray::Sort() {
     // Shift down the new top element.
     int parent_index = 0;
     const uint32_t parent_hash = GetSortedKey(parent_index).hash();
-    const int max_parent_index = (i / 2) - 1;
+    max_parent_index = (i / 2) - 1;
     while (parent_index <= max_parent_index) {
       int child_index = parent_index * 2 + 1;
       uint32_t child_hash = GetSortedKey(child_index).hash();
@@ -5964,15 +5964,15 @@ int BaseNameDictionary<Derived, Shape>::NextEnumerationIndex(
     // Iterate over the dictionary using the enumeration order and update
     // the dictionary with new enumeration indices.
     for (int i = 0; i < length; i++) {
-      InternalIndex index(Smi::ToInt(iteration_order->get(i)));
+      InternalIndex internal_index(Smi::ToInt(iteration_order->get(i)));
       DCHECK(dictionary->IsKey(dictionary->GetReadOnlyRoots(),
-                               dictionary->KeyAt(isolate, index)));
+                               dictionary->KeyAt(isolate, internal_index)));
 
       int enum_index = PropertyDetails::kInitialIndex + i;
 
-      PropertyDetails details = dictionary->DetailsAt(index);
+      PropertyDetails details = dictionary->DetailsAt(internal_index);
       PropertyDetails new_details = details.set_index(enum_index);
-      dictionary->DetailsAtPut(index, new_details);
+      dictionary->DetailsAtPut(internal_index, new_details);
     }
 
     index = PropertyDetails::kInitialIndex + length;

src/objects/scope-info.cc

@@ -298,8 +298,8 @@ Handle<ScopeInfo> ScopeInfo::Create(IsolateT* isolate, Zone* zone, Scope* scope,
       for (int i = 0; i < parameter_count; i++) {
         Variable* parameter = scope->AsDeclarationScope()->parameter(i);
         if (parameter->location() != VariableLocation::CONTEXT) continue;
-        int index = parameter->index() - scope->ContextHeaderLength();
-        int info_index = context_local_info_base + index;
+        int param_index = parameter->index() - scope->ContextHeaderLength();
+        int info_index = context_local_info_base + param_index;
         int info = Smi::ToInt(scope_info.get(info_index));
         info = ParameterNumberBits::update(info, i);
         scope_info.set(info_index, Smi::FromInt(info));

src/objects/source-text-module.cc

@@ -576,15 +576,15 @@ void SourceTextModule::FetchStarExports(Isolate* isolate,
     // the name to undefined instead of a Cell.
     Handle<ObjectHashTable> requested_exports(requested_module->exports(),
                                               isolate);
-    for (InternalIndex i : requested_exports->IterateEntries()) {
+    for (InternalIndex index : requested_exports->IterateEntries()) {
       Object key;
-      if (!requested_exports->ToKey(roots, i, &key)) continue;
+      if (!requested_exports->ToKey(roots, index, &key)) continue;
       Handle<String> name(String::cast(key), isolate);
 
       if (name->Equals(roots.default_string())) continue;
       if (!exports->Lookup(name).IsTheHole(roots)) continue;
 
-      Handle<Cell> cell(Cell::cast(requested_exports->ValueAt(i)), isolate);
+      Handle<Cell> cell(Cell::cast(requested_exports->ValueAt(index)), isolate);
       auto insert_result = more_exports.insert(std::make_pair(name, cell));
       if (!insert_result.second) {
         auto it = insert_result.first;