[turbofan] Introduce CheckHole and CheckHoleNaN operators.

src/compiler/typer.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/compiler/typer.h"
 
 #include "src/base/flags.h"
 #include "src/bootstrapper.h"
 #include "src/compilation-dependencies.h"
 #include "src/compiler/common-operator.h"
@@ skipping 230 matching lines @@
   static Type* ToName(Type*, Typer*);
   static Type* ToNumber(Type*, Typer*);
   static Type* ToObject(Type*, Typer*);
   static Type* ToString(Type*, Typer*);
   static Type* NumberCeil(Type*, Typer*);
   static Type* NumberFloor(Type*, Typer*);
   static Type* NumberRound(Type*, Typer*);
   static Type* NumberTrunc(Type*, Typer*);
   static Type* NumberToInt32(Type*, Typer*);
   static Type* NumberToUint32(Type*, Typer*);
-  static Type* NumberConvertHoleNaN(Type*, Typer*);
 
   static Type* ObjectIsCallable(Type*, Typer*);
   static Type* ObjectIsNumber(Type*, Typer*);
   static Type* ObjectIsReceiver(Type*, Typer*);
   static Type* ObjectIsSmi(Type*, Typer*);
   static Type* ObjectIsString(Type*, Typer*);
   static Type* ObjectIsUndetectable(Type*, Typer*);
 
   static Type* JSAddRanger(RangeType*, RangeType*, Typer*);
   static Type* JSSubtractRanger(RangeType*, RangeType*, Typer*);
@@ skipping 288 matching lines @@
   if (type->Is(Type::Unsigned32())) return type;
   if (type->Is(t->cache_.kZeroish)) return t->cache_.kSingletonZero;
   if (type->Is(t->unsigned32ish_)) {
     return Type::Intersect(
         Type::Union(type, t->cache_.kSingletonZero, t->zone()),
         Type::Unsigned32(), t->zone());
   }
   return Type::Unsigned32();
 }
 
-Type* Typer::Visitor::NumberConvertHoleNaN(Type* type, Typer* t) {
-  return Type::Union(type, Type::Undefined(), t->zone());
-}
-
 // Type checks.
 
 Type* Typer::Visitor::ObjectIsCallable(Type* type, Typer* t) {
   if (type->Is(Type::Function())) return t->singleton_true_;
   if (type->Is(Type::Primitive())) return t->singleton_false_;
   return Type::Boolean();
 }
 
 Type* Typer::Visitor::ObjectIsNumber(Type* type, Typer* t) {
   if (type->Is(Type::Number())) return t->singleton_true_;
@@ skipping 1237 matching lines @@
 Type* Typer::Visitor::TypeNumberToInt32(Node* node) {
   return TypeUnaryOp(node, NumberToInt32);
 }
 
 
 Type* Typer::Visitor::TypeNumberToUint32(Node* node) {
   return TypeUnaryOp(node, NumberToUint32);
 }
 
 
-Type* Typer::Visitor::TypeNumberIsHoleNaN(Node* node) {
-  return Type::Boolean();
-}
-
-Type* Typer::Visitor::TypeNumberConvertHoleNaN(Node* node) {
-  return TypeUnaryOp(node, NumberConvertHoleNaN);
-}
-
 // static
 Type* Typer::Visitor::ReferenceEqualTyper(Type* lhs, Type* rhs, Typer* t) {
   if (lhs->IsConstant() && rhs->Is(lhs)) {
     return t->singleton_true_;
   }
   return Type::Boolean();
 }
 
 
 Type* Typer::Visitor::TypeReferenceEqual(Node* node) {
@@ skipping 128 matching lines @@
 }
 
 Type* Typer::Visitor::TypeCheckedTaggedToInt32(Node* node) {
   return Type::Signed32();
 }
 
 Type* Typer::Visitor::TypeCheckedTaggedToFloat64(Node* node) {
   return Type::Number();
 }
 
+Type* Typer::Visitor::TypeCheckFloat64Hole(Node* node) {
+  Type* type = Operand(node, 0);
+  return type;
+}
+
+Type* Typer::Visitor::TypeCheckTaggedHole(Node* node) {
+  CheckTaggedHoleMode mode = CheckTaggedHoleModeOf(node->op());
+  Type* type = Operand(node, 0);
+  type = Type::Intersect(type, Type::NonInternal(), zone());
+  switch (mode) {
+    case CheckTaggedHoleMode::kConvertHoleToUndefined: {
+      // The hole is turned into undefined.
+      type = Type::Union(type, Type::Undefined(), zone());
+      break;
+    }
+    case CheckTaggedHoleMode::kNeverReturnHole: {
+      // We deoptimize in case of the hole.
+      break;
+    }
+  }
+  return type;
+}
+
 Type* Typer::Visitor::TypeCheckIf(Node* node) {
   UNREACHABLE();
   return nullptr;
 }
 
 Type* Typer::Visitor::TypeTruncateTaggedToWord32(Node* node) {
   Type* arg = Operand(node, 0);
   // TODO(jarin): DCHECK(arg->Is(Type::NumberOrUndefined()));
   // Several mjsunit and cctest tests fail this check. For instance,
   // mjsunit/compiler/regress-607493 fails with Any/Any in simplified-lowering
@@ skipping 707 matching lines @@
   }
   if (Type::IsInteger(*value)) {
     return Type::Range(value->Number(), value->Number(), zone());
   }
   return Type::Constant(value, zone());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8