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* Export of internal Abseil changesGravatar Abseil Team2019-12-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | -- b842b7fd9b1289be31f0b7ee8e62e48e550747cf by Greg Falcon <gfalcon@google.com>: Change the Cord str_format formatter to use iteration instead of CordReader. When Cord is publicly released, CordReader is not going with it. PiperOrigin-RevId: 284780736 -- 28e76c08ea7185a7ff9f4e0e02ae565fbbf7980f by Greg Falcon <gfalcon@google.com>: Implementation detail change. Introduce ABSL_NAMESPACE_BEGIN and _END annotation macros which indicate the beginning and end of a `namespace absl` scope. Currently these do nothing, but they will be used to inject an inline namespace for LTS builds (to avoid symbol collisions against other Abseil versions). These macros should not be used by end users, because end users should never write `namespace absl {` in their own code. This CL applies these annotations to all code under //absl/base/. The rest of Abseil will be annotated in this way in follow-up CLs. PiperOrigin-RevId: 284776410 -- e1711dc6d696dcca50d4e7d4b4d8f3076575b7ec by Abseil Team <absl-team@google.com>: --help changed to report long flags. PiperOrigin-RevId: 284757720 -- 78f66a68f428bbbd19d8d60e1125f43ba765fd35 by Tom Manshreck <shreck@google.com>: Update comment on + or - in SimpleAToi() PiperOrigin-RevId: 284231843 GitOrigin-RevId: b842b7fd9b1289be31f0b7ee8e62e48e550747cf Change-Id: I3046b31391bd11c8bc4abab7785a863c377cd757
* Changed HTTP URLs to HTTPS where possible (#270)Gravatar nik72732019-03-08
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* Export of internal Abseil changes.Gravatar Abseil Team2019-01-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | -- 5804cc13b413412988248835459b90cd15ec43d9 by Abseil Team <absl-team@google.com>: Mark raw_hash_set::clear() with the ABSL_ATTRIBUTE_REINITIALIZES attribute. This prevents false positives in the clang-tidy check bugprone-use-after-move; it allows reset() to be called on a moved-from raw_hash_set without any warnings, and the raw_hash_set will thereafter be regarded as initialized again. PiperOrigin-RevId: 230717196 -- ff5961a5600ae19b69a9cba6912126cdf2858f38 by CJ Johnson <johnsoncj@google.com>: Swaps DisableIfIntegral<> for EnableIfInputIterator<> for Iterator member functions of InlinedVector PiperOrigin-RevId: 230559521 -- 3f9754ccbeecbd40f235c6f2465279e045ff51d9 by Derek Mauro <dmauro@google.com>: Import GitHub PR 254 https://github.com/abseil/abseil-cpp/pull/254 Fixes warnings from -Wclass-memaccess (base_internal::ThreadIdentity? with no trivial copy-assignment). PiperOrigin-RevId: 230536048 -- 8af03a654ce9a4a7f55384bc7eb1ed64878ac2ec by Chris Kennelly <ckennelly@google.com>: absl: cap SpinLock backoff to 4ms The current backoff logic has 3 problems: 1. It can produce too high values (up to 256ms), which can negatively affect tail latency. The value was chosen long time ago and now it's a good idea to reconsider it. 2. It does not have low bound, so on any iteration it can produce a very small value that will lead to unnecessary cpu consumption. 3. It does not increase low bound with the number of iterations. So if the SpinLock is actually somehow locked for a very prolonged time, a waiter can still wake periodically. Rework the logic to solve these problems. Add lower bound of 128us, no code should rely on absence of episodic delays in this range as they can occur everywhere. Lower upper bound to 4ms. A thread sleeping for 4ms does not consume significant cpu time (see below). Grow lower bound with the number of iterations. This is cpu consumption of a process doing usleep(x) in a loop (sampled with ps): 64us -> 4.0% 128us -> 2.7% 256us -> 3.5% 512us -> 2.8% 1024us -> 1.6% 2048us -> 0.6% 4096us -> 0.3% 8192us -> 0.0% Few millisecond sleeps do not consume significant time. PiperOrigin-RevId: 230534015 -- 37ebba92289ca556cb2412cd8b3cb4c1ead3def7 by Samuel Benzaquen <sbenza@google.com>: Add override and dispose hooks to the hashtable sampler. PiperOrigin-RevId: 230353438 -- 89c8f90175233ce9964eb3412df04e8a3cff0c0f by Andy Getzendanner <durandal@google.com>: Fix a comment typo. PiperOrigin-RevId: 229986838 GitOrigin-RevId: 5804cc13b413412988248835459b90cd15ec43d9 Change-Id: Iedb5e2cc9c0b924635c1c87b537780ab6b5b899f
* Export of internal Abseil changes.Gravatar Abseil Team2018-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | -- ee19e203eca970ff88e8f25ce4e19c32e143b988 by Jon Cohen <cohenjon@google.com>: Exception safety testing no longer uses absl::optional PiperOrigin-RevId: 220336204 -- 460666eb0b316a8b4aeedc589644d53b05251bd1 by Derek Mauro <dmauro@google.com>: Rework SwissTable SSE2 support - Use SSE2 on MSVC when available https://github.com/abseil/abseil-cpp/issues/210 - Emulate _mm_cmpgt_epi8 with other SSE2 instructions when using -funsigned-char under GCC https://github.com/abseil/abseil-cpp/issues/209 PiperOrigin-RevId: 220312351 -- 1f4318ecedf8d539b7b698eb803d613ad6b69278 by Abseil Team <absl-team@google.com>: Change CollectPerfectRatios to use 10 trials to smooth out the outliers in the sample. PiperOrigin-RevId: 220286579 -- 6755abc2673553a7f578bb29c6e9ca8d991bc9c8 by Abseil Team <absl-team@google.com>: Internal change PiperOrigin-RevId: 220274307 -- 8645b6187329ebf0aaf3c2de2888ba44466cd879 by Abseil Team <absl-team@google.com>: * #endif for a header guard should reference the guard macro in a comment PiperOrigin-RevId: 220206868 -- 3987a7ad11319230910931cd2468b60b3fd1b85c by Gennadiy Civil <misterg@google.com>: Internal Change PiperOrigin-RevId: 220136674 -- cc908c1db2ee0d4523dc813e33f600583bb986c5 by Abseil Team <absl-team@google.com>: absl: fix backoff logic in SpinLockWait There are 3 bugs in loop variable handling: 1. It starts with 0, but AbslInternalSpinLockDelay ignores loop == 0. So it does not actually wait when it should. 2. loop is incremented after successful state changes, but it should not (why would be increase backoff delay after that?). 3. loop is incremented after CAS failures, but it should not (why would be increase backoff delay after that?). Use the same handling of loop as used in SpinLock. PiperOrigin-RevId: 220136079 -- a0a1c6ef5910ebd28e07215d7df03cc0da0b3eed by Abseil Team <absl-team@google.com>: absl: relax unnecessarily strong memory ordering in SpinLock::SlowLock We don't need to acquire visibility over anything when setting kSpinLockSleeper. Replace the confusing and unnecessarily strong memory order with relaxed. PiperOrigin-RevId: 220023380 -- c50858b51af28b9fca1a62616324f85f3e84ea74 by Tom Manshreck <shreck@google.com>: Update comments in flat_hash_map, node_hash_{set, map} and the containers developer guide PiperOrigin-RevId: 219938692 -- e87b7d1a5f61e165b1c44d3b16d8d967197cdfce by CJ Johnson <johnsoncj@google.com>: Rearranges the public methods of InlinedVector and cleans up the comments PiperOrigin-RevId: 219896257 -- f3234c466f792e0fc4bfd21fc7919dba5e679375 by CJ Johnson <johnsoncj@google.com>: Adds branch prediction to exceptional early exit cases of inlined vector's API PiperOrigin-RevId: 219887173 -- 4dfccf1a81ca0425912d3da25a8470f78c532ce4 by CJ Johnson <johnsoncj@google.com>: Fixes the InlinedVector public interface to use the allocator type references instead of assuming the type Also cleans up some cruft in formatting and comments PiperOrigin-RevId: 219878876 -- 4bb6a2b892abb10bd6a424db7e94ed8640802470 by Tom Manshreck <shreck@google.com>: Add comments on constructor and assignment operator support to flat_hash_set PiperOrigin-RevId: 219825338 -- c23f973e2f7f4feea0da36bf8a9c3f8a8954bb74 by Abseil Team <absl-team@google.com>: Import of CCTZ from GitHub. PiperOrigin-RevId: 219823847 GitOrigin-RevId: ee19e203eca970ff88e8f25ce4e19c32e143b988 Change-Id: I288c927ca481dc57340420dbb4c278a05cf15e83
* Export of internal Abseil changes.Gravatar Abseil Team2018-08-20
| | | | | | | | | | | | | | | | | | -- c508ee8bcc38dad1019c0ad744c47ac70efd36b7 by Derek Mauro <dmauro@google.com>: Opensource the Linux specific SpinLock Wait/Wake implementation. PiperOrigin-RevId: 209420888 -- c13113e19973d496f3e798c0e6d5569c78e41466 by Derek Mauro <dmauro@google.com>: Fix build error from https://github.com/abseil/abseil-cpp/issues/159 PiperOrigin-RevId: 209152118 GitOrigin-RevId: c508ee8bcc38dad1019c0ad744c47ac70efd36b7 Change-Id: I1a287df973198f9e26936d8f91031bb354db0c71
* Changes imported from Abseil "staging" branch:Gravatar Abseil Team2018-02-22
| | | | | | | | - db061dd2b795837e6154be0991077ca5a03ec471 Release the async-signal safe demangler as an internal im... by Derek Mauro <dmauro@google.com> - 310440eb33d946df79d26bf1edf795f6a0b466b9 Use static_cast to constrain nanoseconds to int range, av... by Abseil Team <absl-team@google.com> GitOrigin-RevId: db061dd2b795837e6154be0991077ca5a03ec471 Change-Id: Ibc1bc1db355a48115451da5ce88d66a1f6e1a182
* Changes imported from Abseil "staging" branch:Gravatar Abseil Team2017-10-24
| | | | | | | | | | | | - fbff677ef850865ea67ed6771a8ed348be181e8e Modify sysinfo.cc to support GetTID on Akaros. by Abseil Team <absl-team@google.com> - f1c2929e08a3d4181e08cb5014c4a569306fd922 Two functions that did not refer to their arguments unles... by Abseil Team <absl-team@google.com> - ee43cc3bfdb4d84d40eee31fb25ecdc1aa060f47 Support Akaros (https://akaros.org) in the ABSL spinlock_... by Abseil Team <absl-team@google.com> - 6869c8c5253126459d6c7f0aa708d8612c8e5963 Make sure vdso_base_ is constant-intialized. by Abseil Team <absl-team@google.com> - d54e0366efc8d44cd5da5fd157734da966dc45e8 Add missing include for assert used by ABSL_ASSERT. by Derek Mauro <dmauro@google.com> - a5139775f3917bb5201e7fc838135766daa05b8d When building against GLIBC-2.16 or newer, use getauxval(... by Abseil Team <absl-team@google.com> GitOrigin-RevId: fbff677ef850865ea67ed6771a8ed348be181e8e Change-Id: Ie3549f6ef054783dd104304d2faf8d9800c16b83
* Initial CommitGravatar misterg2017-09-19
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