[turbofan] Optimize typeof in abstract/strict equality comparison.

src/compiler/js-typed-lowering.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/code-factory.h"
 #include "src/compilation-dependencies.h"
 #include "src/compiler/access-builder.h"
 #include "src/compiler/js-graph.h"
 #include "src/compiler/js-typed-lowering.h"
 #include "src/compiler/linkage.h"
@@ skipping 477 matching lines @@
         break;
       default:
         return NoChange();
     }
     return r.ChangeToPureOperator(comparison);
   }
   // TODO(turbofan): relax/remove effects of this operator in other cases.
   return NoChange();  // Keep a generic comparison.
 }
 
+Reduction JSTypedLowering::ReduceJSEqualTypeOf(Node* node, bool invert) {
+  HeapObjectBinopMatcher m(node);
+  if (m.left().IsJSTypeOf() && m.right().HasValue() &&
+      m.right().Value()->IsString()) {
+    Node* replacement;
+    Node* input = m.left().InputAt(0);
+    Handle<String> value = Handle<String>::cast(m.right().Value());
+    if (String::Equals(value, factory()->boolean_string())) {
+      replacement = graph()->NewNode(
+          common()->Select(MachineRepresentation::kTagged),
+          graph()->NewNode(simplified()->ReferenceEqual(Type::Any()), input,
+                           jsgraph()->TrueConstant()),
+          jsgraph()->TrueConstant(),
+          graph()->NewNode(simplified()->ReferenceEqual(Type::Any()), input,
+                           jsgraph()->FalseConstant()));
+    } else if (String::Equals(value, factory()->function_string())) {
+      replacement = graph()->NewNode(simplified()->ObjectIsCallable(), input);
+    } else if (String::Equals(value, factory()->number_string())) {
+      replacement = graph()->NewNode(simplified()->ObjectIsNumber(), input);
+    } else if (String::Equals(value, factory()->string_string())) {
+      replacement = graph()->NewNode(simplified()->ObjectIsString(), input);
+    } else if (String::Equals(value, factory()->undefined_string())) {
+      replacement = graph()->NewNode(
+          common()->Select(MachineRepresentation::kTagged),
+          graph()->NewNode(simplified()->ReferenceEqual(Type::Any()), input,
+                           jsgraph()->NullConstant()),
+          jsgraph()->FalseConstant(),
+          graph()->NewNode(simplified()->ObjectIsUndetectable(), input));
+    } else {
+      return NoChange();
+    }
+    if (invert) {
+      replacement = graph()->NewNode(simplified()->BooleanNot(), replacement);
+    }
+    return Replace(replacement);
+  }
+  return NoChange();
+}
 
 Reduction JSTypedLowering::ReduceJSEqual(Node* node, bool invert) {
   if (flags() & kDisableBinaryOpReduction) return NoChange();
 
+  Reduction const reduction = ReduceJSEqualTypeOf(node, invert);
+  if (reduction.Changed()) {
+    ReplaceWithValue(node, reduction.replacement());
+    return reduction;
+  }
+
   JSBinopReduction r(this, node);
 
   if (r.BothInputsAre(Type::Number())) {
     return r.ChangeToPureOperator(simplified()->NumberEqual(), invert);
   }
   if (r.BothInputsAre(Type::String())) {
     return r.ChangeToPureOperator(simplified()->StringEqual(), invert);
   }
   if (r.BothInputsAre(Type::Boolean())) {
     return r.ChangeToPureOperator(simplified()->ReferenceEqual(Type::Boolean()),
@@ skipping 36 matching lines @@
   }
   if (r.OneInputCannotBe(Type::NumberOrString())) {
     // For values with canonical representation (i.e. not string nor number) an
     // empty type intersection means the values cannot be strictly equal.
     if (!r.left_type()->Maybe(r.right_type())) {
       Node* replacement = jsgraph()->BooleanConstant(invert);
       ReplaceWithValue(node, replacement);
       return Replace(replacement);
     }
   }
+  Reduction const reduction = ReduceJSEqualTypeOf(node, invert);
+  if (reduction.Changed()) {
+    return reduction;
+  }
   if (r.OneInputIs(the_hole_type_)) {
     return r.ChangeToPureOperator(simplified()->ReferenceEqual(the_hole_type_),
                                   invert);
   }
   if (r.OneInputIs(Type::Undefined())) {
     return r.ChangeToPureOperator(
         simplified()->ReferenceEqual(Type::Undefined()), invert);
   }
   if (r.OneInputIs(Type::Null())) {
     return r.ChangeToPureOperator(simplified()->ReferenceEqual(Type::Null()),
@@ skipping 1217 matching lines @@
 }
 
 
 CompilationDependencies* JSTypedLowering::dependencies() const {
   return dependencies_;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8