Export of internal Abseil changes

--
2ba0e41a21fbdab36b2f4f3b0dd4b112bd788604 by Derek Mauro <dmauro@google.com>:

Remove the include of <intsafe.h>, which is missing on
some versions of MinGW. DWORD is easily replaced by uint32_t.

PiperOrigin-RevId: 282576177

--
238fd41114b3e83fcb91d2afe1e6dcce7cfd53b0 by Samuel Benzaquen <sbenza@google.com>:

Remove assertion in erase(iterator) that tries to use the comparator.
Add missing this-> qualifier.
Fix bug where node elements are not being destroyed properly.

PiperOrigin-RevId: 282427096

--
6b9446e3b38ed97451c010933e86a572ab659ab2 by Derek Mauro <dmauro@google.com>:

Improves/fixes feature detection in thread_identity

Only use ABSL_PER_THREAD_TLS_KEYWORD when it is supported (previously
on some platforms it evaluated to nothing, which completely breaks
everything), but prefer it to thread_local since benchmarks indicate
it is slightly faster in this critical code path.

Disable the calls to pthread_sigmask on MinGW where it is not
supported.

PiperOrigin-RevId: 282425291
GitOrigin-RevId: 2ba0e41a21fbdab36b2f4f3b0dd4b112bd788604
Change-Id: I34073ecbb4a43ad71f54161c136d88fc728888f1

8 files changed, 119 insertions, 48 deletions

diff --git a/absl/base/internal/sysinfo.cc b/absl/base/internal/sysinfo.cc
index 4dd3adda..93039bf2 100644
--- a/absl/base/internal/sysinfo.cc
+++ b/absl/base/internal/sysinfo.cc
@@ -277,7 +277,7 @@ double NominalCPUFrequency() {
 #if defined(_WIN32)
 
 pid_t GetTID() {
-  return GetCurrentThreadId();
+  return pid_t{GetCurrentThreadId()};
 }
 
 #elif defined(__linux__)
diff --git a/absl/base/internal/sysinfo.h b/absl/base/internal/sysinfo.h
index b864a597..93356d80 100644
--- a/absl/base/internal/sysinfo.h
+++ b/absl/base/internal/sysinfo.h
@@ -26,10 +26,10 @@
 
 #ifndef _WIN32
 #include <sys/types.h>
-#else
-#include <intsafe.h>
 #endif
 
+#include <cstdint>
+
 #include "absl/base/port.h"
 
 namespace absl {
@@ -51,9 +51,10 @@ int NumCPUs();
 // On Linux, you may send a signal to the resulting ID with kill().  However,
 // it is recommended for portability that you use pthread_kill() instead.
 #ifdef _WIN32
-// On Windows, process id and thread id are of the same type according to
-// the return types of GetProcessId() and GetThreadId() are both DWORD.
-using pid_t = DWORD;
+// On Windows, process id and thread id are of the same type according to the
+// return types of GetProcessId() and GetThreadId() are both DWORD, an unsigned
+// 32-bit type.
+using pid_t = uint32_t;
 #endif
 pid_t GetTID();
 
diff --git a/absl/base/internal/thread_identity.cc b/absl/base/internal/thread_identity.cc
index 91273a6b..0ea159c5 100644
--- a/absl/base/internal/thread_identity.cc
+++ b/absl/base/internal/thread_identity.cc
@@ -55,7 +55,12 @@ void AllocateThreadIdentityKey(ThreadIdentityReclaimerFunction reclaimer) {
 #ifdef __GNUC__
 __attribute__((visibility("protected")))
 #endif  // __GNUC__
-  ABSL_PER_THREAD_TLS_KEYWORD ThreadIdentity* thread_identity_ptr;
+#if ABSL_PER_THREAD_TLS
+// Prefer __thread to thread_local as benchmarks indicate it is a bit faster.
+ABSL_PER_THREAD_TLS_KEYWORD ThreadIdentity* thread_identity_ptr = nullptr;
+#elif defined(ABSL_HAVE_THREAD_LOCAL)
+thread_local ThreadIdentity* thread_identity_ptr = nullptr;
+#endif  // ABSL_PER_THREAD_TLS
 #endif  // TLS or CPP11
 
 void SetCurrentThreadIdentity(
@@ -69,8 +74,8 @@ void SetCurrentThreadIdentity(
   absl::call_once(init_thread_identity_key_once, AllocateThreadIdentityKey,
                   reclaimer);
 
-#ifdef __EMSCRIPTEN__
-  // Emscripten PThread implementation does not support signals.
+#if defined(__EMSCRIPTEN__) || defined(__MINGW32__)
+  // Emscripten and MinGW pthread implementations does not support signals.
   // See https://kripken.github.io/emscripten-site/docs/porting/pthreads.html
   // for more information.
   pthread_setspecific(thread_identity_pthread_key,
@@ -89,7 +94,7 @@ void SetCurrentThreadIdentity(
   pthread_setspecific(thread_identity_pthread_key,
                       reinterpret_cast<void*>(identity));
   pthread_sigmask(SIG_SETMASK, &curr_signals, nullptr);
-#endif  // !__EMSCRIPTEN__
+#endif  // !__EMSCRIPTEN__ && !__MINGW32__
 
 #elif ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_TLS
   // NOTE: Not async-safe.  But can be open-coded.
diff --git a/absl/base/internal/thread_identity.h b/absl/base/internal/thread_identity.h
index b34674a6..7cbce9cc 100644
--- a/absl/base/internal/thread_identity.h
+++ b/absl/base/internal/thread_identity.h
@@ -224,7 +224,14 @@ void ClearCurrentThreadIdentity();
 #if ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_TLS || \
     ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_CPP11
 
-extern ABSL_PER_THREAD_TLS_KEYWORD ThreadIdentity* thread_identity_ptr;
+#if ABSL_PER_THREAD_TLS
+ABSL_CONST_INIT extern ABSL_PER_THREAD_TLS_KEYWORD ThreadIdentity*
+    thread_identity_ptr;
+#elif defined(ABSL_HAVE_THREAD_LOCAL)
+ABSL_CONST_INIT extern thread_local ThreadIdentity* thread_identity_ptr;
+#else
+#error Thread-local storage not detected on this platform
+#endif
 
 inline ThreadIdentity* CurrentThreadIdentityIfPresent() {
   return thread_identity_ptr;
diff --git a/absl/container/btree_test.cc b/absl/container/btree_test.cc
index 48f70cb0..ea73f032 100644
--- a/absl/container/btree_test.cc
+++ b/absl/container/btree_test.cc
@@ -45,6 +45,7 @@ namespace absl {
 namespace container_internal {
 namespace {
 
+using ::absl::test_internal::CopyableMovableInstance;
 using ::absl::test_internal::InstanceTracker;
 using ::absl::test_internal::MovableOnlyInstance;
 using ::testing::ElementsAre;
@@ -1823,25 +1824,80 @@ TEST(Btree, ExtractAndInsertNodeHandleSet) {
   EXPECT_EQ(res.node.value(), 3);
 }
 
-struct Deref {
-  bool operator()(const std::unique_ptr<int> &lhs,
-                  const std::unique_ptr<int> &rhs) const {
-    return *lhs < *rhs;
+template <typename Set>
+void TestExtractWithTrackingForSet() {
+  InstanceTracker tracker;
+  {
+    Set s;
+    // Add enough elements to make sure we test internal nodes too.
+    const size_t kSize = 1000;
+    while (s.size() < kSize) {
+      s.insert(MovableOnlyInstance(s.size()));
+    }
+    for (int i = 0; i < kSize; ++i) {
+      // Extract with key
+      auto nh = s.extract(MovableOnlyInstance(i));
+      EXPECT_EQ(s.size(), kSize - 1);
+      EXPECT_EQ(nh.value().value(), i);
+      // Insert with node
+      s.insert(std::move(nh));
+      EXPECT_EQ(s.size(), kSize);
+
+      // Extract with iterator
+      auto it = s.find(MovableOnlyInstance(i));
+      nh = s.extract(it);
+      EXPECT_EQ(s.size(), kSize - 1);
+      EXPECT_EQ(nh.value().value(), i);
+      // Insert with node and hint
+      s.insert(s.begin(), std::move(nh));
+      EXPECT_EQ(s.size(), kSize);
+    }
   }
-};
+  EXPECT_EQ(0, tracker.instances());
+}
+
+template <typename Map>
+void TestExtractWithTrackingForMap() {
+  InstanceTracker tracker;
+  {
+    Map m;
+    // Add enough elements to make sure we test internal nodes too.
+    const size_t kSize = 1000;
+    while (m.size() < kSize) {
+      m.insert(
+          {CopyableMovableInstance(m.size()), MovableOnlyInstance(m.size())});
+    }
+    for (int i = 0; i < kSize; ++i) {
+      // Extract with key
+      auto nh = m.extract(CopyableMovableInstance(i));
+      EXPECT_EQ(m.size(), kSize - 1);
+      EXPECT_EQ(nh.key().value(), i);
+      EXPECT_EQ(nh.mapped().value(), i);
+      // Insert with node
+      m.insert(std::move(nh));
+      EXPECT_EQ(m.size(), kSize);
+
+      // Extract with iterator
+      auto it = m.find(CopyableMovableInstance(i));
+      nh = m.extract(it);
+      EXPECT_EQ(m.size(), kSize - 1);
+      EXPECT_EQ(nh.key().value(), i);
+      EXPECT_EQ(nh.mapped().value(), i);
+      // Insert with node and hint
+      m.insert(m.begin(), std::move(nh));
+      EXPECT_EQ(m.size(), kSize);
+    }
+  }
+  EXPECT_EQ(0, tracker.instances());
+}
 
-TEST(Btree, ExtractWithUniquePtr) {
-  absl::btree_set<std::unique_ptr<int>, Deref> s;
-  s.insert(absl::make_unique<int>(1));
-  s.insert(absl::make_unique<int>(2));
-  s.insert(absl::make_unique<int>(3));
-  s.insert(absl::make_unique<int>(4));
-  s.insert(absl::make_unique<int>(5));
-  auto nh = s.extract(s.find(absl::make_unique<int>(3)));
-  EXPECT_EQ(s.size(), 4);
-  EXPECT_EQ(*nh.value(), 3);
-  s.insert(std::move(nh));
-  EXPECT_EQ(s.size(), 5);
+TEST(Btree, ExtractTracking) {
+  TestExtractWithTrackingForSet<absl::btree_set<MovableOnlyInstance>>();
+  TestExtractWithTrackingForSet<absl::btree_multiset<MovableOnlyInstance>>();
+  TestExtractWithTrackingForMap<
+      absl::btree_map<CopyableMovableInstance, MovableOnlyInstance>>();
+  TestExtractWithTrackingForMap<
+      absl::btree_multimap<CopyableMovableInstance, MovableOnlyInstance>>();
 }
 
 TEST(Btree, ExtractAndInsertNodeHandleMultiSet) {
diff --git a/absl/container/internal/btree.h b/absl/container/internal/btree.h
index cf7ef02c..40217dd5 100644
--- a/absl/container/internal/btree.h
+++ b/absl/container/internal/btree.h
@@ -2031,7 +2031,6 @@ auto btree<P>::erase(iterator iter) -> iterator {
     iterator internal_iter(iter);
     --iter;
     assert(iter.node->leaf());
-    assert(!compare_keys(internal_iter.key(), iter.key()));
     params_type::move(mutable_allocator(), iter.node->slot(iter.position),
                       internal_iter.node->slot(internal_iter.position));
     internal_delete = true;
diff --git a/absl/container/internal/btree_container.h b/absl/container/internal/btree_container.h
index 726861d5..774412d9 100644
--- a/absl/container/internal/btree_container.h
+++ b/absl/container/internal/btree_container.h
@@ -296,9 +296,10 @@ class btree_set_container : public btree_container<Tree> {
   insert_return_type insert(node_type &&node) {
     if (!node) return {this->end(), false, node_type()};
     std::pair<iterator, bool> res =
-        insert(std::move(params_type::element(CommonAccess::GetSlot(node))));
+        this->tree_.insert_unique(params_type::key(CommonAccess::GetSlot(node)),
+                                  CommonAccess::GetSlot(node));
     if (res.second) {
-      CommonAccess::Reset(&node);
+      CommonAccess::Destroy(&node);
       return {res.first, true, node_type()};
     } else {
       return {res.first, false, std::move(node)};
@@ -308,8 +309,8 @@ class btree_set_container : public btree_container<Tree> {
     if (!node) return this->end();
     std::pair<iterator, bool> res = this->tree_.insert_hint_unique(
         iterator(hint), params_type::key(CommonAccess::GetSlot(node)),
-        std::move(params_type::element(CommonAccess::GetSlot(node))));
-    if (res.second) CommonAccess::Reset(&node);
+        CommonAccess::GetSlot(node));
+    if (res.second) CommonAccess::Destroy(&node);
     return res.first;
   }
 
@@ -323,7 +324,7 @@ class btree_set_container : public btree_container<Tree> {
   // Node extraction routines.
   template <typename K = key_type>
   node_type extract(const key_arg<K> &key) {
-    auto it = find(key);
+    auto it = this->find(key);
     return it == this->end() ? node_type() : extract(it);
   }
   using super_type::extract;
@@ -523,24 +524,21 @@ class btree_multiset_container : public btree_container<Tree> {
     return this->tree_.insert_hint_multi(
         iterator(position), init_type(std::forward<Args>(args)...));
   }
-
- private:
-  template <typename... Args>
-  iterator insert_node_helper(node_type &&node, Args &&... args) {
+  iterator insert(node_type &&node) {
     if (!node) return this->end();
     iterator res =
-        insert(std::forward<Args>(args)...,
-               std::move(params_type::element(CommonAccess::GetSlot(node))));
-    CommonAccess::Reset(&node);
+        this->tree_.insert_multi(params_type::key(CommonAccess::GetSlot(node)),
+                                 CommonAccess::GetSlot(node));
+    CommonAccess::Destroy(&node);
     return res;
   }
-
- public:
-  iterator insert(node_type &&node) {
-    return insert_node_helper(std::move(node));
-  }
   iterator insert(const_iterator hint, node_type &&node) {
-    return insert_node_helper(std::move(node), hint);
+    if (!node) return this->end();
+    iterator res = this->tree_.insert_hint_multi(
+        iterator(hint),
+        std::move(params_type::element(CommonAccess::GetSlot(node))));
+    CommonAccess::Destroy(&node);
+    return res;
   }
 
   // Deletion routines.
@@ -553,7 +551,7 @@ class btree_multiset_container : public btree_container<Tree> {
   // Node extraction routines.
   template <typename K = key_type>
   node_type extract(const key_arg<K> &key) {
-    auto it = find(key);
+    auto it = this->find(key);
     return it == this->end() ? node_type() : extract(it);
   }
   using super_type::extract;
diff --git a/absl/container/internal/common.h b/absl/container/internal/common.h
index 4bd5d469..cc7633dc 100644
--- a/absl/container/internal/common.h
+++ b/absl/container/internal/common.h
@@ -167,6 +167,11 @@ struct CommonAccess {
   }
 
   template <typename Node>
+  static void Destroy(Node* node) {
+    node->destroy();
+  }
+
+  template <typename Node>
   static void Reset(Node* node) {
     node->reset();
   }