[turbofan] Optimize %_IsJSReceiver based on input type.

src/compiler/js-intrinsic-lowering.cc

 // Copyright 2015 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/js-intrinsic-lowering.h"
 
 #include <stack>
 
 #include "src/code-factory.h"
 #include "src/compiler/access-builder.h"
@@ skipping 225 matching lines @@
   // Replace all effect uses of {node} with the {ephi}.
   Node* ephi = graph()->NewNode(common()->EffectPhi(2), etrue, efalse, merge);
   ReplaceWithValue(node, node, ephi);
 
   // Turn the {node} into a Phi.
   return Change(node, common()->Phi(type, 2), vtrue, vfalse, merge);
 }
 
 
 Reduction JSIntrinsicLowering::ReduceIsJSReceiver(Node* node) {
-  // if (%_IsSmi(value)) {
-  //   return false;
-  // } else {
-  //   return FIRST_JS_RECEIVER_TYPE <= %_GetInstanceType(%_GetMap(value))
-  // }
-  STATIC_ASSERT(LAST_TYPE == LAST_JS_RECEIVER_TYPE);
-  MachineType const type = static_cast<MachineType>(kTypeBool | kRepTagged);
-
   Node* value = NodeProperties::GetValueInput(node, 0);
+  Type* value_type = NodeProperties::GetType(value);
   Node* effect = NodeProperties::GetEffectInput(node);
   Node* control = NodeProperties::GetControlInput(node);
+  if (value_type->Is(Type::Receiver())) {
+    value = jsgraph()->TrueConstant();
+  } else if (!value_type->Maybe(Type::Receiver())) {
+    value = jsgraph()->FalseConstant();
+  } else {
+    // if (%_IsSmi(value)) {
+    //   return false;
+    // } else {
+    //   return FIRST_JS_RECEIVER_TYPE <= %_GetInstanceType(%_GetMap(value))
+    // }
+    STATIC_ASSERT(LAST_TYPE == LAST_JS_RECEIVER_TYPE);
 
-  Node* check = graph()->NewNode(simplified()->ObjectIsSmi(), value);
-  Node* branch = graph()->NewNode(common()->Branch(), check, control);
+    Node* check = graph()->NewNode(simplified()->ObjectIsSmi(), value);
+    Node* branch = graph()->NewNode(common()->Branch(), check, control);
 
-  Node* if_true = graph()->NewNode(common()->IfTrue(), branch);
-  Node* etrue = effect;
-  Node* vtrue = jsgraph()->FalseConstant();
+    Node* if_true = graph()->NewNode(common()->IfTrue(), branch);
+    Node* etrue = effect;
+    Node* vtrue = jsgraph()->FalseConstant();
 
-  Node* if_false = graph()->NewNode(common()->IfFalse(), branch);
-  Node* efalse = graph()->NewNode(
-      simplified()->LoadField(AccessBuilder::ForMapInstanceType()),
-      graph()->NewNode(simplified()->LoadField(AccessBuilder::ForMap()), value,
-                       effect, if_false),
-      effect, if_false);
-  Node* vfalse = graph()->NewNode(
-      machine()->Uint32LessThanOrEqual(),
-      jsgraph()->Int32Constant(FIRST_JS_RECEIVER_TYPE), efalse);
+    Node* if_false = graph()->NewNode(common()->IfFalse(), branch);
+    Node* efalse = graph()->NewNode(
+        simplified()->LoadField(AccessBuilder::ForMapInstanceType()),
+        graph()->NewNode(simplified()->LoadField(AccessBuilder::ForMap()),
+                         value, effect, if_false),
+        effect, if_false);
+    Node* vfalse = graph()->NewNode(
+        machine()->Uint32LessThanOrEqual(),
+        jsgraph()->Int32Constant(FIRST_JS_RECEIVER_TYPE), efalse);
 
-  control = graph()->NewNode(common()->Merge(2), if_true, if_false);
-
-  // Replace all effect uses of {node} with the {ephi}.
-  effect = graph()->NewNode(common()->EffectPhi(2), etrue, efalse, control);
+    control = graph()->NewNode(common()->Merge(2), if_true, if_false);
+    effect = graph()->NewNode(common()->EffectPhi(2), etrue, efalse, control);
+    value = graph()->NewNode(common()->Phi(kMachAnyTagged, 2), vtrue, vfalse,
+                             control);
+  }
   ReplaceWithValue(node, node, effect, control);
-
-  // Turn the {node} into a Phi.
-  return Change(node, common()->Phi(type, 2), vtrue, vfalse, control);
+  return Replace(value);
 }
 
 
 Reduction JSIntrinsicLowering::ReduceIsSmi(Node* node) {
   return Change(node, simplified()->ObjectIsSmi());
 }
 
 
 Reduction JSIntrinsicLowering::ReduceJSValueGetValue(Node* node) {
   Node* value = NodeProperties::GetValueInput(node, 0);
@@ skipping 350 matching lines @@
 }
 
 
 SimplifiedOperatorBuilder* JSIntrinsicLowering::simplified() const {
   return jsgraph()->simplified();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8