1 files changed, 115 insertions, 0 deletions
diff --git a/deps/v8/src/string-constants.h b/deps/v8/src/string-constants.h
new file mode 100644
index 0000000000..b7134849db
--- /dev/null
+++ b/deps/v8/src/string-constants.h
@@ -0,0 +1,115 @@
+// 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_STRING_CONSTANTS_H_
+#define V8_STRING_CONSTANTS_H_
+
+#include "src/objects/string.h"
+#include "src/zone/zone.h"
+
+namespace v8 {
+namespace internal {
+
+enum class StringConstantKind {
+  kStringLiteral,
+  kNumberToStringConstant,
+  kStringCons
+};
+
+class StringConstantBase : public ZoneObject {
+ public:
+  explicit StringConstantBase(StringConstantKind kind) : kind_(kind) {}
+
+  StringConstantKind kind() const { return kind_; }
+  Handle<String> AllocateStringConstant(Isolate* isolate) const;
+
+  size_t GetMaxStringConstantLength() const;
+
+  bool operator==(const StringConstantBase& other) const;
+
+ private:
+  void Memoize(Handle<String> flattened) const { flattened_ = flattened; }
+
+  StringConstantKind kind_;
+  mutable Handle<String> flattened_ = Handle<String>::null();
+};
+
+size_t hash_value(StringConstantBase const& base);
+
+class StringLiteral final : public StringConstantBase {
+ public:
+  explicit StringLiteral(Handle<String> str, size_t length)
+      : StringConstantBase(StringConstantKind::kStringLiteral),
+        str_(str),
+        length_(length) {}
+
+  Handle<String> str() const { return str_; }
+
+  size_t GetMaxStringConstantLength() const;
+
+ private:
+  Handle<String> str_;
+  size_t length_;  // We store this separately to avoid accessing the heap.
+};
+
+bool operator==(StringLiteral const& lhs, StringLiteral const& rhs);
+bool operator!=(StringLiteral const& lhs, StringLiteral const& rhs);
+
+size_t hash_value(StringLiteral const& parameters);
+
+std::ostream& operator<<(std::ostream& os, StringLiteral const& parameters);
+
+class NumberToStringConstant final : public StringConstantBase {
+ public:
+  explicit NumberToStringConstant(double num)
+      : StringConstantBase(StringConstantKind::kNumberToStringConstant),
+        num_(num) {}
+
+  double num() const { return num_; }
+
+  size_t GetMaxStringConstantLength() const;
+
+ private:
+  double num_;
+};
+
+bool operator==(NumberToStringConstant const& lhs,
+                NumberToStringConstant const& rhs);
+bool operator!=(NumberToStringConstant const& lhs,
+                NumberToStringConstant const& rhs);
+
+size_t hash_value(NumberToStringConstant const& parameters);
+
+std::ostream& operator<<(std::ostream& os,
+                         NumberToStringConstant const& parameters);
+
+class StringCons final : public StringConstantBase {
+ public:
+  explicit StringCons(const StringConstantBase* lhs,
+                      const StringConstantBase* rhs)
+      : StringConstantBase(StringConstantKind::kStringCons),
+        lhs_(lhs),
+        rhs_(rhs) {}
+
+  const StringConstantBase* lhs() const { return lhs_; }
+  const StringConstantBase* rhs() const { return rhs_; }
+
+  size_t GetMaxStringConstantLength() const;
+
+ private:
+  const StringConstantBase* lhs_;
+  const StringConstantBase* rhs_;
+};
+
+bool operator==(StringCons const& lhs, StringCons const& rhs);
+bool operator!=(StringCons const& lhs, StringCons const& rhs);
+
+size_t hash_value(StringCons const& parameters);
+
+std::ostream& operator<<(std::ostream& os, StringCons const& parameters);
+
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_STRING_CONSTANTS_H_