1 files changed, 107 insertions, 0 deletions
diff --git a/deps/v8/src/objects/smi.h b/deps/v8/src/objects/smi.h
new file mode 100644
index 0000000000..0361ef0a7a
--- /dev/null
+++ b/deps/v8/src/objects/smi.h
@@ -0,0 +1,107 @@
+// Copyright 2018 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_OBJECTS_SMI_H_
+#define V8_OBJECTS_SMI_H_
+
+#include "src/globals.h"
+#include "src/objects/heap-object.h"
+
+// Has to be the last include (doesn't have include guards):
+#include "src/objects/object-macros.h"
+
+namespace v8 {
+namespace internal {
+
+// Smi represents integer Numbers that can be stored in 31 bits.
+// Smis are immediate which means they are NOT allocated in the heap.
+// The ptr_ value has the following format: [31 bit signed int] 0
+// For long smis it has the following format:
+//     [32 bit signed int] [31 bits zero padding] 0
+// Smi stands for small integer.
+class Smi : public Object {
+ public:
+  // This replaces the OBJECT_CONSTRUCTORS macro, because Smis are special
+  // in that we want them to be constexprs.
+  constexpr Smi() : Object() {}
+  explicit constexpr Smi(Address ptr) : Object(ptr) {
+#if V8_CAN_HAVE_DCHECK_IN_CONSTEXPR
+    DCHECK(HAS_SMI_TAG(ptr));
+#endif
+  }
+  Smi* operator->() { return this; }
+  const Smi* operator->() const { return this; }
+
+  // Returns the integer value.
+  inline int value() const { return Internals::SmiValue(ptr()); }
+  inline Smi ToUint32Smi() {
+    if (value() <= 0) return Smi::FromInt(0);
+    return Smi::FromInt(static_cast<uint32_t>(value()));
+  }
+
+  // Convert a Smi object to an int.
+  static inline int ToInt(const Object object);
+
+  // Convert a value to a Smi object.
+  static inline constexpr Smi FromInt(int value) {
+#if V8_CAN_HAVE_DCHECK_IN_CONSTEXPR
+    DCHECK(Smi::IsValid(value));
+#endif
+    return Smi(Internals::IntToSmi(value));
+  }
+
+  static inline Smi FromIntptr(intptr_t value) {
+    DCHECK(Smi::IsValid(value));
+    int smi_shift_bits = kSmiTagSize + kSmiShiftSize;
+    return Smi((value << smi_shift_bits) | kSmiTag);
+  }
+
+  template <typename E,
+            typename = typename std::enable_if<std::is_enum<E>::value>::type>
+  static inline Smi FromEnum(E value) {
+    STATIC_ASSERT(sizeof(E) <= sizeof(int));
+    return FromInt(static_cast<int>(value));
+  }
+
+  // Returns whether value can be represented in a Smi.
+  static inline bool constexpr IsValid(intptr_t value) {
+#if V8_CAN_HAVE_DCHECK_IN_CONSTEXPR
+    DCHECK(Internals::IsValidSmi(value) ==
+           (value >= kMinValue && value <= kMaxValue));
+#endif
+    return Internals::IsValidSmi(value);
+  }
+
+  // Compare two Smis x, y as if they were converted to strings and then
+  // compared lexicographically. Returns:
+  // -1 if x < y.
+  //  0 if x == y.
+  //  1 if x > y.
+  // Returns the result (a tagged Smi) as a raw Address for ExternalReference
+  // usage.
+  static Address LexicographicCompare(Isolate* isolate, Smi x, Smi y);
+
+  DECL_CAST(Smi)
+
+  // Dispatched behavior.
+  V8_EXPORT_PRIVATE void SmiPrint(std::ostream& os) const;  // NOLINT
+  DECL_VERIFIER(Smi)
+
+  // C++ does not allow us to have an object of type Smi within class Smi,
+  // so the kZero value has type Object. Consider it deprecated; new code
+  // should use zero() instead.
+  V8_EXPORT_PRIVATE static constexpr Object kZero = Object(0);
+  // If you need something with type Smi, call zero() instead. Since it is
+  // a constexpr, "calling" it is just as efficient as reading kZero.
+  static inline constexpr Smi zero() { return Smi::FromInt(0); }
+  static constexpr int kMinValue = kSmiMinValue;
+  static constexpr int kMaxValue = kSmiMaxValue;
+};
+
+}  // namespace internal
+}  // namespace v8
+
+#include "src/objects/object-macros-undef.h"
+
+#endif  // V8_OBJECTS_SMI_H_