[llvm] r317077 - Revert rL317019, "[ADT] Split optional to only include copy mechanics and dtor for non-trivial types."
NAKAMURA Takumi via llvm-commits
llvm-commits at lists.llvm.org
Tue Oct 31 22:14:31 PDT 2017
Author: chapuni
Date: Tue Oct 31 22:14:31 2017
New Revision: 317077
URL: http://llvm.org/viewvc/llvm-project?rev=317077&view=rev
Log:
Revert rL317019, "[ADT] Split optional to only include copy mechanics and dtor for non-trivial types."
Seems g++-4.8 (eg. Ubuntu 14.04) doesn't like this.
Modified:
llvm/trunk/include/llvm/ADT/Optional.h
llvm/trunk/unittests/ADT/OptionalTest.cpp
Modified: llvm/trunk/include/llvm/ADT/Optional.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/Optional.h?rev=317077&r1=317076&r2=317077&view=diff
==============================================================================
--- llvm/trunk/include/llvm/ADT/Optional.h (original)
+++ llvm/trunk/include/llvm/ADT/Optional.h Tue Oct 31 22:14:31 2017
@@ -27,164 +27,114 @@
namespace llvm {
-namespace optional_detail {
-/// Storage for any type.
-template <typename T, bool IsPodLike> struct OptionalStorage {
+template<typename T>
+class Optional {
AlignedCharArrayUnion<T> storage;
bool hasVal = false;
- OptionalStorage() = default;
+public:
+ using value_type = T;
+
+ Optional(NoneType) {}
+ explicit Optional() {}
+
+ Optional(const T &y) : hasVal(true) {
+ new (storage.buffer) T(y);
+ }
- OptionalStorage(const T &y) : hasVal(true) { new (storage.buffer) T(y); }
- OptionalStorage(const OptionalStorage &O) : hasVal(O.hasVal) {
+ Optional(const Optional &O) : hasVal(O.hasVal) {
if (hasVal)
- new (storage.buffer) T(*O.getPointer());
+ new (storage.buffer) T(*O);
}
- OptionalStorage(T &&y) : hasVal(true) {
+
+ Optional(T &&y) : hasVal(true) {
new (storage.buffer) T(std::forward<T>(y));
}
- OptionalStorage(OptionalStorage &&O) : hasVal(O.hasVal) {
- if (O.hasVal) {
- new (storage.buffer) T(std::move(*O.getPointer()));
+
+ Optional(Optional<T> &&O) : hasVal(O) {
+ if (O) {
+ new (storage.buffer) T(std::move(*O));
O.reset();
}
}
- OptionalStorage &operator=(T &&y) {
+ ~Optional() {
+ reset();
+ }
+
+ Optional &operator=(T &&y) {
if (hasVal)
- *getPointer() = std::move(y);
+ **this = std::move(y);
else {
new (storage.buffer) T(std::move(y));
hasVal = true;
}
return *this;
}
- OptionalStorage &operator=(OptionalStorage &&O) {
- if (!O.hasVal)
+
+ Optional &operator=(Optional &&O) {
+ if (!O)
reset();
else {
- *this = std::move(*O.getPointer());
+ *this = std::move(*O);
O.reset();
}
return *this;
}
+ /// Create a new object by constructing it in place with the given arguments.
+ template<typename ...ArgTypes>
+ void emplace(ArgTypes &&...Args) {
+ reset();
+ hasVal = true;
+ new (storage.buffer) T(std::forward<ArgTypes>(Args)...);
+ }
+
+ static inline Optional create(const T* y) {
+ return y ? Optional(*y) : Optional();
+ }
+
// FIXME: these assignments (& the equivalent const T&/const Optional& ctors)
// could be made more efficient by passing by value, possibly unifying them
// with the rvalue versions above - but this could place a different set of
// requirements (notably: the existence of a default ctor) when implemented
// in that way. Careful SFINAE to avoid such pitfalls would be required.
- OptionalStorage &operator=(const T &y) {
+ Optional &operator=(const T &y) {
if (hasVal)
- *getPointer() = y;
+ **this = y;
else {
new (storage.buffer) T(y);
hasVal = true;
}
return *this;
}
- OptionalStorage &operator=(const OptionalStorage &O) {
- if (!O.hasVal)
+
+ Optional &operator=(const Optional &O) {
+ if (!O)
reset();
else
- *this = *O.getPointer();
+ *this = *O;
return *this;
}
- ~OptionalStorage() { reset(); }
-
void reset() {
if (hasVal) {
- (*getPointer()).~T();
+ (**this).~T();
hasVal = false;
}
}
- T *getPointer() {
- assert(hasVal);
- return reinterpret_cast<T *>(storage.buffer);
- }
- const T *getPointer() const {
- assert(hasVal);
- return reinterpret_cast<const T *>(storage.buffer);
- }
-};
-
-/// Storage for trivially copyable types only.
-template <typename T> struct OptionalStorage<T, true> {
- AlignedCharArrayUnion<T> storage;
- bool hasVal = false;
-
- OptionalStorage() = default;
-
- OptionalStorage(const T &y) : hasVal(true) { new (storage.buffer) T(y); }
- OptionalStorage &operator=(const T &y) {
- new (storage.buffer) T(y);
- hasVal = true;
- return *this;
- }
-
- void reset() { hasVal = false; }
-};
-} // namespace optional_detail
-
-template <typename T> class Optional {
- optional_detail::OptionalStorage<T, isPodLike<T>::value> Storage;
-
-public:
- using value_type = T;
-
- constexpr Optional() {}
- constexpr Optional(NoneType) {}
-
- Optional(const T &y) : Storage(y) {}
- Optional(const Optional &O) = default;
-
- Optional(T &&y) : Storage(std::forward<T>(y)) {}
- Optional(Optional &&O) = default;
-
- Optional &operator=(T &&y) {
- Storage = std::move(y);
- return *this;
- }
- Optional &operator=(Optional &&O) = default;
-
- /// Create a new object by constructing it in place with the given arguments.
- template <typename... ArgTypes> void emplace(ArgTypes &&... Args) {
- reset();
- Storage.hasVal = true;
- new (getPointer()) T(std::forward<ArgTypes>(Args)...);
- }
-
- static inline Optional create(const T *y) {
- return y ? Optional(*y) : Optional();
- }
-
- Optional &operator=(const T &y) {
- Storage = y;
- return *this;
- }
- Optional &operator=(const Optional &O) = default;
-
- void reset() { Storage.reset(); }
-
- const T *getPointer() const {
- assert(Storage.hasVal);
- return reinterpret_cast<const T *>(Storage.storage.buffer);
- }
- T *getPointer() {
- assert(Storage.hasVal);
- return reinterpret_cast<T *>(Storage.storage.buffer);
- }
- const T &getValue() const LLVM_LVALUE_FUNCTION { return *getPointer(); }
- T &getValue() LLVM_LVALUE_FUNCTION { return *getPointer(); }
+ const T* getPointer() const { assert(hasVal); return reinterpret_cast<const T*>(storage.buffer); }
+ T* getPointer() { assert(hasVal); return reinterpret_cast<T*>(storage.buffer); }
+ const T& getValue() const LLVM_LVALUE_FUNCTION { assert(hasVal); return *getPointer(); }
+ T& getValue() LLVM_LVALUE_FUNCTION { assert(hasVal); return *getPointer(); }
- explicit operator bool() const { return Storage.hasVal; }
- bool hasValue() const { return Storage.hasVal; }
+ explicit operator bool() const { return hasVal; }
+ bool hasValue() const { return hasVal; }
const T* operator->() const { return getPointer(); }
T* operator->() { return getPointer(); }
- const T &operator*() const LLVM_LVALUE_FUNCTION { return *getPointer(); }
- T &operator*() LLVM_LVALUE_FUNCTION { return *getPointer(); }
+ const T& operator*() const LLVM_LVALUE_FUNCTION { assert(hasVal); return *getPointer(); }
+ T& operator*() LLVM_LVALUE_FUNCTION { assert(hasVal); return *getPointer(); }
template <typename U>
constexpr T getValueOr(U &&value) const LLVM_LVALUE_FUNCTION {
@@ -192,8 +142,8 @@ public:
}
#if LLVM_HAS_RVALUE_REFERENCE_THIS
- T &&getValue() && { return std::move(*getPointer()); }
- T &&operator*() && { return std::move(*getPointer()); }
+ T&& getValue() && { assert(hasVal); return std::move(*getPointer()); }
+ T&& operator*() && { assert(hasVal); return std::move(*getPointer()); }
template <typename U>
T getValueOr(U &&value) && {
Modified: llvm/trunk/unittests/ADT/OptionalTest.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/ADT/OptionalTest.cpp?rev=317077&r1=317076&r2=317077&view=diff
==============================================================================
--- llvm/trunk/unittests/ADT/OptionalTest.cpp (original)
+++ llvm/trunk/unittests/ADT/OptionalTest.cpp Tue Oct 31 22:14:31 2017
@@ -518,14 +518,5 @@ TEST_F(OptionalTest, OperatorGreaterEqua
CheckRelation<GreaterEqual>(InequalityLhs, InequalityRhs, !IsLess);
}
-#if (__has_feature(is_trivially_copyable) && defined(_LIBCPP_VERSION)) || \
- (defined(__GNUC__) && __GNUC__ >= 5)
-static_assert(std::is_trivially_copyable<Optional<int>>::value,
- "Should be trivially copyable");
-static_assert(
- !std::is_trivially_copyable<Optional<NonDefaultConstructible>>::value,
- "Shouldn't be trivially copyable");
-#endif
-
} // end anonymous namespace
More information about the llvm-commits
mailing list