[turbofan] Eliminate CheckHeapObject if the input cannot be in SignedSmall range.

R=jarin@chromium.org

Review-Url: https://codereview.chromium.org/2425613002
Cr-Commit-Position: refs/heads/master@{#40339}

src/compiler/typed-optimization.cc

@@ -74,6 +74,8 @@ Reduction TypedOptimization::Reduce(Node* node) {
     }
   }
   switch (node->opcode()) {
+    case IrOpcode::kCheckHeapObject:
+      return ReduceCheckHeapObject(node);
     case IrOpcode::kCheckMaps:
       return ReduceCheckMaps(node);
     case IrOpcode::kCheckString:
@@ -107,6 +109,16 @@ MaybeHandle<Map> GetStableMapFromObjectType(Type* object_type) {
 
 }  // namespace
 
+Reduction TypedOptimization::ReduceCheckHeapObject(Node* node) {
+  Node* const input = NodeProperties::GetValueInput(node, 0);
+  Type* const input_type = NodeProperties::GetType(input);
+  if (!input_type->Maybe(Type::SignedSmall())) {
+    ReplaceWithValue(node, input);
+    return Replace(input);
+  }
+  return NoChange();
+}
+
 Reduction TypedOptimization::ReduceCheckMaps(Node* node) {
   // The CheckMaps(o, ...map...) can be eliminated if map is stable,
   // o has type Constant(object) and map == object->map, and either

src/compiler/typed-optimization.h

@@ -39,6 +39,7 @@ class TypedOptimization final : public AdvancedReducer {
   Reduction Reduce(Node* node) final;
 
  private:
+  Reduction ReduceCheckHeapObject(Node* node);
   Reduction ReduceCheckMaps(Node* node);
   Reduction ReduceCheckString(Node* node);
   Reduction ReduceLoadField(Node* node);