commit e369bd98ca8d65a4d9facbb6b82ae315165fc61c
author Vy Nguyen <vyng@google.com> Mon Jul 13 12:34:37 2020 -0400
committer Vy Nguyen <vyng@google.com> Mon Jul 20 11:54:34 2020 -0400
tree bc4eaaa5f61ca8a3e6bda3cb7bcb584c70619dba
parent 21ed63f0d2f6971e7c33f496feac3ac79212b17b

Reland [libcxx]Put clang::trivial_abi on smart pointers

    Reviewed By: ldionne,EricWF

    Tags: #libcxx

    Differential Revision: https://reviews.llvm.org/D82490

Cr-Mirrored-From: https://chromium.googlesource.com/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 76887bc4c102a73669a95002d6a06121e7515e68

include/__config

diff --git a/include/__config b/include/__config
index 3b019a0..ebdd64e 100644
--- a/include/__config
+++ b/include/__config
@@ -105,6 +105,10 @@
 // Re-worked external template instantiations for std::string with a focus on
 // performance and fast-path inlining.
 #  define _LIBCPP_ABI_STRING_OPTIMIZED_EXTERNAL_INSTANTIATION
+// Enable clang::trivial_abi on std::unique_ptr.
+#  define _LIBCPP_ABI_ENABLE_UNIQUE_PTR_TRIVIAL_ABI
+// Enable clang::trivial_abi on std::shared_ptr and std::weak_ptr
+#  define _LIBCPP_ABI_ENABLE_SHARED_PTR_TRIVIAL_ABI
 #elif _LIBCPP_ABI_VERSION == 1
 #  if !defined(_LIBCPP_OBJECT_FORMAT_COFF)
 // Enable compiling copies of now inline methods into the dylib to support

include/memory

diff --git a/include/memory b/include/memory
index 1f9f36c..e38e805 100644
--- a/include/memory
+++ b/include/memory
@@ -338,7 +338,7 @@
     pointer release() noexcept;
     void reset(pointer p = pointer()) noexcept;
     void reset(nullptr_t) noexcept;
-    template <class U> void reset(U) = delete;
+  template <class U> void reset(U) = delete;
     void swap(unique_ptr& u) noexcept;
 };
 
@@ -2316,8 +2316,14 @@
   typedef false_type __enable_rval_overload;
 };
 
+#if defined(_LIBCPP_ABI_ENABLE_UNIQUE_PTR_TRIVIAL_ABI)
+#  define _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI __attribute__((trivial_abi))
+#else
+#  define _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI
+#endif
+
 template <class _Tp, class _Dp = default_delete<_Tp> >
-class _LIBCPP_TEMPLATE_VIS unique_ptr {
+class _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS unique_ptr {
 public:
   typedef _Tp element_type;
   typedef _Dp deleter_type;
@@ -2525,7 +2531,7 @@
 
 
 template <class _Tp, class _Dp>
-class _LIBCPP_TEMPLATE_VIS unique_ptr<_Tp[], _Dp> {
+class _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS unique_ptr<_Tp[], _Dp> {
 public:
   typedef _Tp element_type;
   typedef _Dp deleter_type;
@@ -3537,8 +3543,14 @@
     : is_convertible<_Tp*, _Up*> {};
 #endif // _LIBCPP_STD_VER > 14
 
+#if defined(_LIBCPP_ABI_ENABLE_SHARED_PTR_TRIVIAL_ABI)
+#  define _LIBCPP_SHARED_PTR_TRIVIAL_ABI __attribute__((trivial_abi))
+#else
+#  define _LIBCPP_SHARED_PTR_TRIVIAL_ABI
+#endif
+
 template<class _Tp>
-class _LIBCPP_TEMPLATE_VIS shared_ptr
+class _LIBCPP_SHARED_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS shared_ptr
 {
 public:
 #if _LIBCPP_STD_VER > 14
@@ -4526,7 +4538,7 @@
 #endif  // _LIBCPP_NO_RTTI
 
 template<class _Tp>
-class _LIBCPP_TEMPLATE_VIS weak_ptr
+class _LIBCPP_SHARED_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS weak_ptr
 {
 public:
     typedef _Tp element_type;