[compiler] Fix -Wshadow warnings

Bug: v8:12244,v8:12245
Change-Id: I7f5067c9a329ac27bb4ec72d97a7509028ae648a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3269176Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77803}

src/compiler/js-native-context-specialization.cc

@@ -597,9 +597,10 @@ Reduction JSNativeContextSpecialization::ReduceJSHasInPrototypeChain(
     InferHasInPrototypeChainResult result =
         InferHasInPrototypeChain(value, effect, m.Ref(broker()));
     if (result != kMayBeInPrototypeChain) {
-      Node* value = jsgraph()->BooleanConstant(result == kIsInPrototypeChain);
-      ReplaceWithValue(node, value);
-      return Replace(value);
+      Node* result_in_chain =
+          jsgraph()->BooleanConstant(result == kIsInPrototypeChain);
+      ReplaceWithValue(node, result_in_chain);
+      return Replace(result_in_chain);
     }
   }
 
@@ -1130,19 +1131,19 @@ Reduction JSNativeContextSpecialization::ReduceNamedAccess(
   }
 
   // Either infer maps from the graph or use the feedback.
-  ZoneVector<MapRef> lookup_start_object_maps(zone());
-  if (!InferMaps(lookup_start_object, effect, &lookup_start_object_maps)) {
+  ZoneVector<MapRef> inferred_maps(zone());
+  if (!InferMaps(lookup_start_object, effect, &inferred_maps)) {
     for (const MapRef& map : feedback.maps()) {
-      lookup_start_object_maps.push_back(map);
+      inferred_maps.push_back(map);
     }
   }
-  RemoveImpossibleMaps(lookup_start_object, &lookup_start_object_maps);
+  RemoveImpossibleMaps(lookup_start_object, &inferred_maps);
 
   // Check if we have an access o.x or o.x=v where o is the target native
   // contexts' global proxy, and turn that into a direct access to the
   // corresponding global object instead.
-  if (lookup_start_object_maps.size() == 1) {
-    MapRef lookup_start_object_map = lookup_start_object_maps[0];
+  if (inferred_maps.size() == 1) {
+    MapRef lookup_start_object_map = inferred_maps[0];
     if (lookup_start_object_map.equals(
             native_context().global_proxy_object().map())) {
       if (!native_context().GlobalIsDetached()) {
@@ -1161,7 +1162,7 @@ Reduction JSNativeContextSpecialization::ReduceNamedAccess(
   ZoneVector<PropertyAccessInfo> access_infos(zone());
   {
     ZoneVector<PropertyAccessInfo> access_infos_for_feedback(zone());
-    for (const MapRef& map : lookup_start_object_maps) {
+    for (const MapRef& map : inferred_maps) {
       if (map.is_deprecated()) continue;
       PropertyAccessInfo access_info = broker()->GetPropertyAccessInfo(
           map, feedback.name(), access_mode, dependencies());

src/compiler/js-type-hint-lowering.cc

@@ -325,9 +325,8 @@ JSTypeHintLowering::LoweringResult JSTypeHintLowering::ReduceUnaryOperation(
       if (!node) {
         if (jsgraph()->machine()->Is64()) {
           if (GetBinaryOperationHint(slot) == BinaryOperationHint::kBigInt) {
-            const Operator* op =
-                jsgraph()->simplified()->SpeculativeBigIntNegate(
-                    BigIntOperationHint::kBigInt);
+            op = jsgraph()->simplified()->SpeculativeBigIntNegate(
+                BigIntOperationHint::kBigInt);
             node = jsgraph()->graph()->NewNode(op, operand, effect, control);
           }
         }

src/compiler/js-typed-lowering.cc

@@ -1197,7 +1197,7 @@ Reduction JSTypedLowering::ReduceJSHasInPrototypeChain(Node* node) {
   // If {value} cannot be a receiver, then it cannot have {prototype} in
   // it's prototype chain (all Primitive values have a null prototype).
   if (value_type.Is(Type::Primitive())) {
-    Node* value = jsgraph()->FalseConstant();
+    value = jsgraph()->FalseConstant();
     ReplaceWithValue(node, value, effect, control);
     return Replace(value);
   }
@@ -1789,7 +1789,6 @@ Reduction JSTypedLowering::ReduceJSCall(Node* node) {
       // Patch {node} to a direct code object call.
       Callable callable =
           Builtins::CallableFor(isolate(), shared->builtin_id());
-      CallDescriptor::Flags flags = CallDescriptor::kNeedsFrameState;
 
       const CallInterfaceDescriptor& descriptor = callable.descriptor();
       auto call_descriptor = Linkage::GetStubCallDescriptor(
@@ -2232,11 +2231,11 @@ Reduction JSTypedLowering::ReduceObjectIsArray(Node* node) {
 
   // Constant-fold based on {value} type.
   if (value_type.Is(Type::Array())) {
-    Node* value = jsgraph()->TrueConstant();
+    value = jsgraph()->TrueConstant();
     ReplaceWithValue(node, value);
     return Replace(value);
   } else if (!value_type.Maybe(Type::ArrayOrProxy())) {
-    Node* value = jsgraph()->FalseConstant();
+    value = jsgraph()->FalseConstant();
     ReplaceWithValue(node, value);
     return Replace(value);
   }