[Test patch] Inline hot functions in libcxx shared_ptr
Moves hot functions such as atomic add into the memory header file
so that they can be inlined, which brings performance benefits.
Patch by Kevin Hu, Aditya Kumar, Sebastian Pop
Differential Revision: https://reviews.llvm.org/D24991
llvm-svn: 292184
diff --git a/libcxx/src/memory.cpp b/libcxx/src/memory.cpp
index 8569faf..099f2d6 100644
--- a/libcxx/src/memory.cpp
+++ b/libcxx/src/memory.cpp
@@ -17,28 +17,6 @@
_LIBCPP_BEGIN_NAMESPACE_STD
-namespace
-{
-
-// NOTE: Relaxed and acq/rel atomics (for increment and decrement respectively)
-// should be sufficient for thread safety.
-// See https://llvm.org/bugs/show_bug.cgi?id=22803
-template <class T>
-inline T
-increment(T& t) _NOEXCEPT
-{
- return __libcpp_atomic_add(&t, 1, _AO_Relaxed);
-}
-
-template <class T>
-inline T
-decrement(T& t) _NOEXCEPT
-{
- return __libcpp_atomic_add(&t, -1, _AO_Acq_Rel);
-}
-
-} // namespace
-
const allocator_arg_t allocator_arg = allocator_arg_t();
bad_weak_ptr::~bad_weak_ptr() _NOEXCEPT {}
@@ -53,16 +31,20 @@
{
}
+__shared_weak_count::~__shared_weak_count()
+{
+}
+
void
__shared_count::__add_shared() _NOEXCEPT
{
- increment(__shared_owners_);
+ __libcpp_atomic_refcount_increment(__shared_owners_);
}
bool
__shared_count::__release_shared() _NOEXCEPT
{
- if (decrement(__shared_owners_) == -1)
+ if (__libcpp_atomic_refcount_decrement(__shared_owners_) == -1)
{
__on_zero_shared();
return true;
@@ -70,10 +52,6 @@
return false;
}
-__shared_weak_count::~__shared_weak_count()
-{
-}
-
void
__shared_weak_count::__add_shared() _NOEXCEPT
{
@@ -83,7 +61,7 @@
void
__shared_weak_count::__add_weak() _NOEXCEPT
{
- increment(__shared_weak_owners_);
+ __libcpp_atomic_refcount_increment(__shared_weak_owners_);
}
void
@@ -124,7 +102,7 @@
//__libcpp_atomic_store(&__shared_weak_owners_, -1, _AO_Release);
__on_zero_shared_weak();
}
- else if (decrement(__shared_weak_owners_) == -1)
+ else if (__libcpp_atomic_refcount_decrement(__shared_weak_owners_) == -1)
__on_zero_shared_weak();
}
