Summary: [Folly] A cache for `InlineExecutor` singleton, which can be inlined into callers with little extra code compared to calling the backing function directly.

Reviewed By: marshallcline

Differential Revision: D8339793

fbshipit-source-id: d2be0128e617cfefe66809eb44ce40e1a8ae2dfb

Summary: [Folly] Write `Promise::setException` in terms of `Promise::setTry`.

Reviewed By: marshallcline

Differential Revision: D8344928

fbshipit-source-id: 90e21219f054329eca7ae1a6c2ca731a16328b6f

Revert D8360404: [folly] Support constructing TDigest from centroids and getting centroids from TDigest

Differential Revision:
D8360404

Original commit changeset: b0f42e892f66

fbshipit-source-id: 985ba55bb443aafe7c324f15caeca0abb34d200a

Summary: Before this diff, since `ctx->memo_` starts out in the `OnlyResult` state, the first reduce (and therefore all subsequent reduces) are run immediately inside the lock.

Reviewed By: yfeldblum

Differential Revision: D8319067

fbshipit-source-id: 5ed08885beefb42c6efb61768fcbc36e0a08a46b

Summary:
To implement tdigest aggregation in scuba, we need to be able to deserialize and serialize the digests.
I added a getter for the centroids so that we can serialize the tdigest, and added a constructor to create one from the list of centroids.

Differential Revision: D8360404

fbshipit-source-id: b0f42e892f666e787e06198c7e8ff65dd8799dcc

Summary:
In folly::small_vector, we were (mistakenly) relying on a default constructor
for non-trivially constructible types.

The problem got worse on gcc 4.9, because for that compiler version, we set
folly::is_trivially_copyable to be std::is_trivial. This is mostly okay, as
std::is_trivial implies std::is_trivially_copyable. The problem is that
std::is_trivial also implies std::is_default_constructuble, which which was
breaking folly::small_vector

Reviewed By: yfeldblum

Differential Revision: D8346780

fbshipit-source-id: 9c8a9dab21ea2d4fd34f636458324915c30e10a2

Summary:
See https://gitlab.kitware.com/cmake/cmake/issues/16686

This patch was originally contributed to MacPorts by mohd-akram in https://github.com/macports/macports-ports/pull/1933.
Closes https://github.com/facebook/folly/pull/862

Reviewed By: Orvid

Differential Revision: D8346974

Pulled By: yfeldblum

fbshipit-source-id: 2673e1f414dd86bf91bb2183c2f6d9f7e72251f8

Summary:
[Folly] A shorter name for executor local variable in `Future` methods. Reads more nicely, with less awkward formatting.

When the scope of a local variable's use is just a few lines, long names are not quite so critical.

Reviewed By: marshallcline

Differential Revision: D8339451

fbshipit-source-id: 5d50cf0ce3473c1a79afeeddb9e1257cccf73e31

Summary: [Folly] No need for qualifying `InlineExecutor` in `Futures` - they are both in `namespace folly` already.

Reviewed By: marshallcline

Differential Revision: D8307058

fbshipit-source-id: 17a0ecde1e57f1c0c88cbac09bbd1bb3daf7a24e

Summary:
[Folly] Use `InlineExecutor` singleton in `Future` wait v.s. letting the executor be `nullptr`.

The effect is the same, but just more explicit.

Reviewed By: marshallcline

Differential Revision: D8306902

fbshipit-source-id: fc90704de670b1ca9956253383fadad3be297847

Summary:
Executor adaptor which allows joining only tasks scheduled through this VirtualExecutor instance without joining all other tasks in a wrapped Executor.
This is very similar to VirtualEventBase, but works for any Executor.

Reviewed By: yfeldblum, aary

Differential Revision: D8342064

fbshipit-source-id: 420b6390e2da88c4826e6d22bc8f3b3585525214

Summary: [Folly] Ensure sleep duration in logging `RateLimiter` test to make sure that there is no chance of waking up from the sleep too early.

Reviewed By: Orvid

Differential Revision: D8330018

fbshipit-source-id: f1222e1da50f8360267f9e1c5e0f24897b7b8f47

Reviewed By: shixiao

Differential Revision: D8333485

fbshipit-source-id: 02f74700272b663474c2f02535265ffb6f4bcd22

Summary:
method-level contracts

(Note: this ignores all push blocking failures!)

Reviewed By: yfeldblum

Differential Revision: D8132350

fbshipit-source-id: d79b1d88a38ea97de8d0e841e822805aff3959ae

Summary:
fbthrift needs to link against newer version of krb5 library to avoid linking
issue during OpenR build.

```
libsecurity.so: undefined reference to `error_message(long)'
```

Reviewed By: yfeldblum

Differential Revision: D8330387

fbshipit-source-id: 34f3f7361c99bb38adf558a52ef05e9d3156640d

Summary:
Make the interface consistent with the other queue algorithms.
push
try_push
try_push_for
try_push_until
pop
try_pop
try_pop_for
try_pop_until
peek
try_peek
try_peek_for
try_peek_until

Reviewed By: yfeldblum, djwatson

Differential Revision: D8262170

fbshipit-source-id: 0299e947a0069eacafd1315c920ec6e1b36675f3

Summary: Weak reference can be used if it's ok for some tasks to be dropped when Executor is destroyed.

Reviewed By: yfeldblum

Differential Revision: D8309958

fbshipit-source-id: 8ecc86a8be181a9eb695aa12305b2a30b6f4b60e

Summary:
Moved `Future::within` to `FutureBase::withinImplementation`, and changed it to return a `SemiFuture`.
`SemiFuture::within` uses it directly, and `Future::within` uses it then attaches the current executor or falls back to the inline executor to preserve existing behavior.

Reviewed By: yfeldblum

Differential Revision: D8269907

fbshipit-source-id: 76e235a2ecb2c648603961d0ac0ac17bf646d027

Summary:
[Folly] Support self-copy in `small_vector`.

And refactor move-assignment to look like the fixed copy-assignment for symmetry.

Reviewed By: Ahmed-Salama

Differential Revision: D8321122

fbshipit-source-id: 2c8b26ad6c4e538266082df29276b827cf4505fc

Summary: When vector intrinsics are not available, `visitAllocationClasses` fails to compile as it is a member function of a template class and it invokes a member function of a template base class without explicit `this->`.

Reviewed By: yfeldblum, nbronson

Differential Revision: D8300168

fbshipit-source-id: 1c1619bd1c864535648e531b218d2cf1ffef767b

Summary:
VLOG(1) shows up in Android logs, which is annoying as some of our
tools try to repeatedly connect.

Reviewed By: yfeldblum

Differential Revision: D8297987

fbshipit-source-id: 45cf4320d2e2fcf570117fee6aef133b2d9986e6

Summary:
There is no guarantee that the default branch in git is 'master'; so
    unless specified we checkout a tag along the 'dev' branch, which is not
    intended as it is the master branch that tracks releases for Zstd.

Reviewed By: jstrizich

Differential Revision: D8297843

fbshipit-source-id: 8497dc75c399ae7c86e27b28fdb73898ef4b1a4e

Summary: `s/Future/SemiFuture/` on `SemiFuture` ctor and fixed typo `s/Timeekeeper/Timekeeper/`.

Reviewed By: yfeldblum

Differential Revision: D8290658

fbshipit-source-id: 99ddbdecc0302e620bd2b4ebce74c6080cf81aec

Make Future<T>::delayed complete on correct executor 5/n: Add back Future::delayed with correct behaviour

Summary:
Overall plan to modify Future<T>::delayed to complete on the same
executor as the input future.

[folly::Futures] Make Future<T>::delayed complete on correct executor 5/n:
 * Add back future::delayed.
 * Have Future::delayed complete on input executor.
 * r-value qualify Future::delayed

Reviewed By: yfeldblum, marshallcline

Differential Revision: D8238220

fbshipit-source-id: 79afa8cc9a9fe588609ad186ad62f714ee322f7d

Summary: [Folly] Let `Sychronized` move-constructor not lock the source object, since it is an rvalue-reference and the move-constructor code may therefore be assumed to have the only live reference to the source. Same with the move-assignment operator.

Reviewed By: aary

Differential Revision: D8219883

fbshipit-source-id: f62ff87197ac4b9ceed290a73a05062ab8ed45c4

Summary:
Reusing a context can provide significant efficiency benefits.

Depends on D8172871.

Reviewed By: yfeldblum, terrelln

Differential Revision: D8287767

fbshipit-source-id: 2565e7a959b2ac0911f0a4d6e1596f9da6d12ee8

Summary:
Reusing a context can provide significant efficiency benefits.

Depends on D8172801.

Reviewed By: yfeldblum, terrelln

Differential Revision: D8172871

fbshipit-source-id: f92c85410a35643502d28922583ee0ed0b4386c9

Summary: Clear/read OpenSSL errors after certain ops.

Reviewed By: mingtaoy

Differential Revision: D8277088

fbshipit-source-id: aa436657c3bca3a081cd56858e09da57a03cda05

Summary: Use static FOLLY_TLS ThreadEntry to avoid an ASAN deadlock due to new after fork

Reviewed By: philippv

Differential Revision: D8272580

fbshipit-source-id: e2dc069e81d15f14be9f96a26d30de7482ced0cf

Summary: Replaced boost::algorithm::to_lower() with std::transform()

Reviewed By: yfeldblum

Differential Revision: D8264760

fbshipit-source-id: f6faa46c0bbced3a08c02b93eacbb58eb6927890

Summary:
* One function needed renaming
* One bug needed to be worked around (content size defaulting to 0)

Reviewed By: yfeldblum

Differential Revision: D8264565

fbshipit-source-id: 1abe5fb79b525108e64857dc28d5582372fcc165

Summary: The instance method is permitted on `const` objects, so the ADL method should also accept a `const&` input.

Reviewed By: yfeldblum

Differential Revision: D8240295

fbshipit-source-id: 960aa5567afea3f52b91c1b83566820f5ecefc4d

Summary:
IntervalRateLimiter was already operating on millisecond
granularity. coarse_steady_clock offers better performance because
it's on millisecond granularity.

Reviewed By: yfeldblum

Differential Revision: D8245042

fbshipit-source-id: 7ce0e347c0498ff2741adc727577c3bb2ce63979

Summary: Iterate only through the threads that have in use entries - v2

Reviewed By: djwatson

Differential Revision: D8143429

fbshipit-source-id: 51098ff8e1fef7aaf9f1c0f2ddbf7ebb579cbeb4

Summary:
[Folly] Cut `FOLLY_IS_TRIVIALLY_COPYABLE` macro, replacing all uses with `folly::is_trivially_copyable`.

And cut `folly::IsTriviallyCopyable` with member-type-detection support, and move `folly::traits_detail::is_trivially_copyable` to `folly::is_trivially_copyable`.

`FOLLY_IS_TRIVIALLY_COPYABLE` and `folly::IsTriviallyCopyable` were there to support gcc < 5.

Reviewed By: Orvid

Differential Revision: D8246972

fbshipit-source-id: 8af9bbdbfac8671a61ebaa200dbfd2426a40d2eb

Summary:
x86_64 chips with SSE >= 4.2 and many aarch64 chips have
CRC32-specific instructions with excellent latency.  This diff switches
the bit mixer applied to untrusted hash functions to use these instructions.
This is a noticeable win for the F14 uses that are CPU front-end bound.

Reviewed By: yfeldblum

Differential Revision: D8245688

fbshipit-source-id: f6a1c1c2a6365201178c653cd5d8c04fbac8d78e

Summary:
Overall plan to modify Future<T>::delayed to complete on the same executor as the input future.

4/n: Remove Future::delayed completely to ensure that all users are on delayedUnsafe so that when we put delayed in with correct behaviour there is no incorrect use.

Reviewed By: marshallcline

Differential Revision: D8223327

fbshipit-source-id: c675d2d51afa2131eee5871afea45f1c6cc65a77

Summary: Minor refactoring of several fbcode/folly/ classes.  Primarily constification, replacing custom code with call to boost, etc.

Reviewed By: yfeldblum

Differential Revision: D8239891

fbshipit-source-id: 14cb109b5deb27f8949b7889d195fcba29e2038c

Summary:
F14 can apply some additional optimizations for trivially
copyable and trivially destructible values in the case that the allocator
doesn't do anything special in its construct and destroy methods.
Previously this was gated based on whether the allocator was exactly
std::allocator, but that causes this optimization to be missed in some
important cases.  This diff extends the checking machinery to test if
there is actually a default construct or destroy method in the allocator
(they are optional) and to test if there is a manual override of the
conservative default check.

Reviewed By: yfeldblum

Differential Revision: D8191437

fbshipit-source-id: c55b8f32427c3f0eff5c8ef42d7b51a57b0cbd1f

Summary:
Core::hasResult() is called in lots of places:

- future.result()
- future.get()
- future.wait()
- future.within()
- future.hasValue()
- future.hasException()
- future.getTry()
- future.raise()
- future.poll()
- promise.setInterruptHandler()
- etc.

This diff improves that function as follows (source: godbolt, with optimization, on both gcc and clang):

- old: 7 instructions w/ 2 conditional jumps + 1 unconditional jump; fastest path is 4 instructions w/ 2 jumps, slowest is 7 instructions w/ 2 jumps
- new: 3 instructions w/ 0 jumps

Small improvement overall, but to a widely used function.

Reviewed By: yfeldblum

Differential Revision: D8231048

fbshipit-source-id: 83a9f5c602475c2ca7066a45635d807596ecf37d