merge(3p/absl): subtree merge of Abseil up to e19260f

... notably, this includes Abseil's own StatusOr type, which
conflicted with our implementation (that was taken from TensorFlow).

Change-Id: Ie7d6764b64055caaeb8dc7b6b9d066291e6b538f
This commit is contained in:
Vincent Ambo 2020-11-21 14:43:54 +01:00
parent cc27324d02
commit 082c006c04
854 changed files with 11260 additions and 5296 deletions

View file

@ -32,6 +32,7 @@
#include "absl/base/config.h"
#include "absl/base/internal/per_thread_tls.h"
#include "absl/base/optimization.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
@ -69,30 +70,28 @@ struct PerThreadSynch {
// is using this PerThreadSynch as a terminator. Its
// skip field must not be filled in because the loop
// might then skip over the terminator.
// The wait parameters of the current wait. waitp is null if the
// thread is not waiting. Transitions from null to non-null must
// occur before the enqueue commit point (state = kQueued in
// Enqueue() and CondVarEnqueue()). Transitions from non-null to
// null must occur after the wait is finished (state = kAvailable in
// Mutex::Block() and CondVar::WaitCommon()). This field may be
// changed only by the thread that describes this PerThreadSynch. A
// special case is Fer(), which calls Enqueue() on another thread,
// but with an identical SynchWaitParams pointer, thus leaving the
// pointer unchanged.
SynchWaitParams *waitp;
bool suppress_fatal_errors; // If true, try to proceed even in the face of
// broken invariants. This is used within fatal
// signal handlers to improve the chances of
// debug logging information being output
// successfully.
intptr_t readers; // Number of readers in mutex.
int priority; // Priority of thread (updated every so often).
// When priority will next be read (cycles).
int64_t next_priority_read_cycles;
bool wake; // This thread is to be woken from a Mutex.
// If "x" is on a waiter list for a mutex, "x->cond_waiter" is true iff the
// waiter is waiting on the mutex as part of a CV Wait or Mutex Await.
//
// The value of "x->cond_waiter" is meaningless if "x" is not on a
// Mutex waiter list.
bool cond_waiter;
bool maybe_unlocking; // Valid at head of Mutex waiter queue;
// true if UnlockSlow could be searching
// for a waiter to wake. Used for an optimization
// in Enqueue(). true is always a valid value.
// Can be reset to false when the unlocker or any
// writer releases the lock, or a reader fully
// releases the lock. It may not be set to false
// by a reader that decrements the count to
// non-zero. protected by mutex spinlock
bool suppress_fatal_errors; // If true, try to proceed even in the face
// of broken invariants. This is used within
// fatal signal handlers to improve the
// chances of debug logging information being
// output successfully.
int priority; // Priority of thread (updated every so often).
// State values:
// kAvailable: This PerThreadSynch is available.
@ -111,30 +110,30 @@ struct PerThreadSynch {
};
std::atomic<State> state;
bool maybe_unlocking; // Valid at head of Mutex waiter queue;
// true if UnlockSlow could be searching
// for a waiter to wake. Used for an optimization
// in Enqueue(). true is always a valid value.
// Can be reset to false when the unlocker or any
// writer releases the lock, or a reader fully releases
// the lock. It may not be set to false by a reader
// that decrements the count to non-zero.
// protected by mutex spinlock
// The wait parameters of the current wait. waitp is null if the
// thread is not waiting. Transitions from null to non-null must
// occur before the enqueue commit point (state = kQueued in
// Enqueue() and CondVarEnqueue()). Transitions from non-null to
// null must occur after the wait is finished (state = kAvailable in
// Mutex::Block() and CondVar::WaitCommon()). This field may be
// changed only by the thread that describes this PerThreadSynch. A
// special case is Fer(), which calls Enqueue() on another thread,
// but with an identical SynchWaitParams pointer, thus leaving the
// pointer unchanged.
SynchWaitParams* waitp;
bool wake; // This thread is to be woken from a Mutex.
intptr_t readers; // Number of readers in mutex.
// If "x" is on a waiter list for a mutex, "x->cond_waiter" is true iff the
// waiter is waiting on the mutex as part of a CV Wait or Mutex Await.
//
// The value of "x->cond_waiter" is meaningless if "x" is not on a
// Mutex waiter list.
bool cond_waiter;
// When priority will next be read (cycles).
int64_t next_priority_read_cycles;
// Locks held; used during deadlock detection.
// Allocated in Synch_GetAllLocks() and freed in ReclaimThreadIdentity().
SynchLocksHeld *all_locks;
};
// The instances of this class are allocated in NewThreadIdentity() with an
// alignment of PerThreadSynch::kAlignment.
struct ThreadIdentity {
// Must be the first member. The Mutex implementation requires that
// the PerThreadSynch object associated with each thread is
@ -212,7 +211,9 @@ void ClearCurrentThreadIdentity();
#define ABSL_THREAD_IDENTITY_MODE ABSL_FORCE_THREAD_IDENTITY_MODE
#elif defined(_WIN32) && !defined(__MINGW32__)
#define ABSL_THREAD_IDENTITY_MODE ABSL_THREAD_IDENTITY_MODE_USE_CPP11
#elif ABSL_PER_THREAD_TLS && defined(__GOOGLE_GRTE_VERSION__) && \
#elif defined(__APPLE__) && defined(ABSL_HAVE_THREAD_LOCAL)
#define ABSL_THREAD_IDENTITY_MODE ABSL_THREAD_IDENTITY_MODE_USE_CPP11
#elif ABSL_PER_THREAD_TLS && defined(__GOOGLE_GRTE_VERSION__) && \
(__GOOGLE_GRTE_VERSION__ >= 20140228L)
// Support for async-safe TLS was specifically added in GRTEv4. It's not
// present in the upstream eglibc.