[turbofan] Add binary operation hints for javascript operators.

src/compiler/type-hints.h

+// 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.
+
+#ifndef V8_COMPILER_TYPE_HINTS_H_
+#define V8_COMPILER_TYPE_HINTS_H_
+
+#include "src/utils.h"
+
+namespace v8 {
+namespace internal {
+namespace compiler {
+
+// Type hints for an binary operation.
+class BinaryOperationHints final {
+ public:
+  enum Hint { kNone, kSignedSmall, kSigned32, kNumber, kString, kAny };
+
+  BinaryOperationHints() : BinaryOperationHints(kNone, kNone, kNone) {}
+  BinaryOperationHints(Hint left, Hint right, Hint result)
+      : bit_field_(LeftField::encode(left) | RightField::encode(right) |
+                   ResultField::encode(result)) {}
+
+  static BinaryOperationHints Any() {
+    return BinaryOperationHints(kAny, kAny, kAny);
+  }
+
+  Hint left() const { return LeftField::decode(bit_field_); }
+  Hint right() const { return RightField::decode(bit_field_); }
+  Hint result() const { return ResultField::decode(bit_field_); }
+
+  bool operator==(BinaryOperationHints const& that) const {
+    return this->bit_field_ == that.bit_field_;
+  }
+  bool operator!=(BinaryOperationHints const& that) const {
+    return !(*this == that);
+  }
+
+  friend size_t hash_value(BinaryOperationHints const& hints) {
+    return hints.bit_field_;
+  }
+
+ private:
+  typedef BitField<Hint, 0, 3> LeftField;
+  typedef BitField<Hint, 3, 3> RightField;
+  typedef BitField<Hint, 6, 3> ResultField;
+
+  uint32_t bit_field_;
+};
+
+std::ostream& operator<<(std::ostream&, BinaryOperationHints::Hint);
+std::ostream& operator<<(std::ostream&, BinaryOperationHints);
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_COMPILER_TYPE_HINTS_H_