Summary: Previously we set the cork option on the socket before making multiple writes, and then unset it after, which elip found was hurting perf with 2 extra syscalls. The cork logic was also not the same as the buffer combining logic, which made us often set cork even when only doing one write.

Reviewed By: djwatson

Differential Revision: D4058357

fbshipit-source-id: 1a07447ff5e027751e455a2403e0042bf67cb1c5

Summary:
A common failure mode for folly::doNotOptimizeAway is to pass it a
pointer to a complex object that the caller wants to ensure is fully
calculated, which doesn't actually ensure that.  Also, the GCC and
MSVC implementations used inline assembly with an in-out parameter,
which causes a store.  A survey of many usages of doNotOptimizeAway
found only 1 that relies on this make-unpredictable behavior.

This diff makes doNotOptimizeAway(&x) equivalent to doNotOptimizeAway(x)
for GCC and clang, and makes it a read-only sink.  For the rare
case that the benchmark wants to disable subexpression elimination,
constant propagation, or power reduction, there is a new function
makeUnpredictable.  It also merges the clang and GCC implementations,
removing a potential bias in our microbenchmarks.

Reviewed By: davidtgoldblatt

Differential Revision: D4074670

fbshipit-source-id: 43f02e7fe149147bb172babe77787dea06e098fa

Summary: In this case, the SpookyHash tests, which call `clock_gettime`.

Reviewed By: yfeldblum

Differential Revision: D4098997

fbshipit-source-id: e402fd6626e59ccc555513384e93ef0ef891bbf3

Summary:
If Folly was compiled without support for SSE 4.2, but this function ends up getting called, we'd abort due to the check failing.
To solve this, just don't do the check and fall back to the non-sse version.

This is reasonable because it means that the code calling `qfind_first_byte_of_sse42` only needs to care whether there is CPU support for SSE 4.2, not whether we were able to actually implement the search with SSE 4.2 based on compiler support.

Reviewed By: yfeldblum

Differential Revision: D4096645

fbshipit-source-id: d26a791c09f61595e40c84c47a7a2596b9b69c1e

Summary:
When using `-fvisibility-inlines-hidden` or using C/C++ shared libs
transitively from a Python binary, static locals in inline functions
can potentially have more than one definition at runtime.  This diff
explicitly marks this static local as safe for this scenario.

Reviewed By: djwatson

Differential Revision: D4082831

fbshipit-source-id: 75616ac26a39f44691ef59b889ea555e9daa391b

Summary:
Now that the initializer list syntax has been removed we can add a default constructor.
Also,
- The `dynamic(T)` constructor was unconstrained, so it would match any type but then fail to compile (as a side effect, `is_convertible<T, dynamic>` would be always true). This also leaked the implementation details of `Array` and `Object`, as they were accepted as arguments. The diff makes the constructor accept only integral and float arguments, and all other types are SFINAEd out.
- `dynamic(Iterator, Iterator)` is made `explicit` to avoid accepting statements like `dynamic d = {"a", "b"};`.
- `object(...)` methods are simplified.

Reviewed By: luciang

Differential Revision: D4065021

fbshipit-source-id: ac289da7bece67c674b7036b7b51d5e016b297e5

Summary:
This refactors inline functions defined in headers which had static locals
so that their definition is moved to the corresponding implementation file.

Reviewed By: yfeldblum

Differential Revision: D4049175

fbshipit-source-id: 56eeb82eb23b04c3b9940d803d05050949aa5ef9

Summary: A bit more clear

Reviewed By: yfeldblum

Differential Revision: D4075931

fbshipit-source-id: 1398500336d412b5e7663ef1e67b20a329ce2979

Summary: Some compilers think result may be uninitialized

Reviewed By: francis-ma

Differential Revision: D4074526

fbshipit-source-id: 5df4568cfa5eb8f3b2993a82b831fd5e4028a281

Summary:
Consider `Expected<..., eUnion>(Expected&&)` ctor, where
`ExpectedUnion` move ctor would be called first, which is noop leaving
`which_`  uninitialized; then `MoveConstructible` ctor is executed, calling
`assignValue()`, which performs action depending on uninitialized `which_`.

Reviewed By: yfeldblum

Differential Revision: D4073199

fbshipit-source-id: 623660e7047afcebf9f72d83f91f84ff6078090f

Summary:
Add a prevPowTwo method to bits.h and optimize the current code for
GCCs output.

Reviewed By: ot

Differential Revision: D4072341

fbshipit-source-id: 6e949d0bfcf88ff8500022939d08a2b5aa9e00c9

Summary:
folly/experimental/symbolizer doesn't actually link with libdwarf, it only requires dwarf.h.
Closes https://github.com/facebook/folly/pull/501

Differential Revision: D4068438

Pulled By: djwatson

fbshipit-source-id: 6339eabf8fceac300caafb478c003833768125fd

Summary:
Add smart pointer types for ec groups
and points

Reviewed By: yfeldblum

Differential Revision: D4066848

fbshipit-source-id: f8a5c59cf902584e5a4bea7265834fcc8898677b

Summary: as above

Reviewed By: yfeldblum

Differential Revision: D4066250

fbshipit-source-id: 7dfe07656dd338ec42fcd966328e46331202bf58

Summary:
This diff adds a method to folly::Function that moves the
Function object into a copyable, callable proxy object.

folly::Function already has the asStdFunction method, which
does the same, but wraps the proxy object in a std::function.
When a copyable shared-state proxy of a folly::Function is needed,
it is not necessarily to turn it into a std::function.
If instead the shared proxy will be passed to several functions
taking folly::Function, what happens is the folly::Function
is moved on the heap, a shared_ptr is put into a std::function,
and that is wrapped in a new folly::Function, which always
requires a memory allocation, because std::function is not
noexcept-movable. When using asSharedProxy instead, an
unspecified copyable type is returned that can implicitly
converted into a folly::Function, but without an additional
memory allocation at this point.

Reviewed By: yfeldblum

Differential Revision: D4048621

fbshipit-source-id: b642027b0a6957058fe0089cceeb657ec52e8669

Summary: It has been deprecated for several months, time to nuke it.

Reviewed By: yfeldblum

Differential Revision: D4045250

fbshipit-source-id: 21b55a7c99602c42b1a87ced6a59788fe0ac25d7

Summary: Someone debugged a runtime crash and traced it back to code like: `vector<fbstring>{{"this", "that"}}`. Presumably the user thought they were passing an initializer list of strings to the vector constructor. Instead, they constructed a single fbstring with two char pointers pointing into //different// strings. With the appropriate fbstring constructors, we can flag this as invalid at compile-time.

Reviewed By: yfeldblum

Differential Revision: D3927397

fbshipit-source-id: ab61e1e8498ec99592a2a7726eaf1cb6324f1455

Summary:
improve documentation of custom singleton creation through an example
(from fbcode SIOF thread suggestion)

Reviewed By: yfeldblum

Differential Revision: D4053322

fbshipit-source-id: e9c2ef3d1ef43d52c0bf0a601d94c017047a23a3

Summary: Someone debugged a runtime crash and traced it back to code like: `vector<fbstring>{{"this", "that"}}`. Presumably the user thought they were passing an initializer list of strings to the vector constructor. Instead, they constructed a single fbstring with two char pointers pointing into //different// strings. With the appropriate fbstring constructors, we can flag this as invalid at compile-time.

Reviewed By: yfeldblum

Differential Revision: D3927397

fbshipit-source-id: a5f335073fb55bbb703a23f06874238cbdb5d91a

Summary:
Nested uses of SYNCHRONIZED (and related) macros leads
inevitably to shadowed variable declarations.
There is already a use of FOLLY_GCC_DISABLE_WARNING(shadow)
to disable -Wshadow in that code, but obviously, that cannot
help with the new options, so do similar for them via
the new FOLLY_GCC_DISABLE_NEW_SHADOW_WARNINGS.

Depends on D4041696

Reviewed By: markisaa

Differential Revision: D4041728

fbshipit-source-id: b85fb3452f6855d359f9b910abbd02cf8433f3f7

Summary:
Add a configure-time check for whether -Wshadow-local and
-Wshadow-compatible-local are supported.  If so, arrange to
define HAVE_SHADOW_LOCAL_WARNINGS.

In Portability.h, use that new symbol to choose whether
to define FOLLY_GCC_DISABLE_NEW_SHADOW_WARNINGS, which
used pragmas to disable those new warnings.

Differential Revision: D4041696

fbshipit-source-id: 520ee88ae55147a13d0a045aca7d86567a8da99d

Summary: add missing includes in folly fibers.q

Reviewed By: A5he

Differential Revision: D4036830

fbshipit-source-id: 4dcb87377979f2875ba31b4869c2637a82298957

Summary: Test fails because of loop unrolling: frames are not being grouped up

Reviewed By: ot

Differential Revision: D4034910

fbshipit-source-id: 159d3a4f116f90fdd0d51ee9de38634167ed0dc4

Summary: This diff adapts the fibers code to the modified `fcontext` API from Boost 1.61

Reviewed By: Orvid

Differential Revision: D4035769

fbshipit-source-id: d3f4b6b03efdd3b6e4b92e0e1c7373747bb74fbb

Summary: Fix warnings exposed by the upstream-proposed -Wshadow-compatible-local option.

Reviewed By: philippv

Differential Revision: D4041749

fbshipit-source-id: 9e0dcec3b35c60e5588a2e53dfdb8605e74721c4

Summary: Fix warnings exposed by the upstream-proposed -Wshadow-compatible-local option.

Reviewed By: igorsugak

Differential Revision: D4041931

fbshipit-source-id: fcddbc8636c16124a9711c4491a08cc7db76a224

Reviewed By: yfeldblum

Differential Revision: D4035412

fbshipit-source-id: 4b7a178088d2950f9f042e0c79b54b3982eb43f5

Summary: Fix warnings exposed by the upstream-proposed -Wshadow-compatible-local option.

Reviewed By: markisaa

Differential Revision: D4041764

fbshipit-source-id: b2aa6543ce4bc36069b010f1107f1ac117073b26

Summary: Fix warnings exposed by the upstream-proposed -Wshadow-compatible-local option.

Reviewed By: igorsugak

Differential Revision: D4041769

fbshipit-source-id: 257bfe9370279f755b8e965ffc1c37fef454d4c4

Summary: Fix warnings exposed by the upstream-proposed -Wshadow-compatible-local option.

Reviewed By: igorsugak

Differential Revision: D4041789

fbshipit-source-id: 79eefaccbe2ca27993ab102ac1b6e3caf3bfb7ce

Summary: Fix warnings exposed by the upstream-proposed -Wshadow-compatible-local option.

Reviewed By: igorsugak

Differential Revision: D4041937

fbshipit-source-id: a9412dae6d1e43931f3b65bffaf462225f667f13

Summary: Fix warnings exposed by the upstream-proposed -Wshadow-compatible-local option.

Reviewed By: igorsugak

Differential Revision: D4041919

fbshipit-source-id: 52579a4b7477192ec7145f81216200f81b191183

Summary: Fix warnings exposed by the upstream-proposed -Wshadow-compatible-local option.

Reviewed By: igorsugak

Differential Revision: D4041910

fbshipit-source-id: d00ea6b294559f80244a226fadf1a3a54c50c78a

Summary: Fix warnings exposed by the upstream-proposed -Wshadow-compatible-local option.

Reviewed By: andrewjcg

Differential Revision: D4041950

fbshipit-source-id: 7c18564273c5839c647709307f56b2fb5e0f6588

Summary: Fix warnings exposed by the upstream-proposed -Wshadow-compatible-local option.

Reviewed By: elsteveogrande

Differential Revision: D4041798

fbshipit-source-id: 9fb6901e791176eb42c31f287655aea6be95a30b

Summary: Fix warnings exposed by the upstream-proposed -Wshadow-compatible-local option.

Differential Revision: D4041756

fbshipit-source-id: 21faf6ad6bf39b0df42e6ef27481d1c81d37ef99

Summary: Fix warnings exposed by the upstream-proposed -Wshadow-compatible-local option.

Reviewed By: nisardan

Differential Revision: D4041779

fbshipit-source-id: 375e485a30f01a0610d881fe8b3237cc062aedef

Summary:
CodeMod: `dynamic-init-list-ctor`.

The `folly::dynamic::dynamic(std::initializer_list<folly::dynamic>)` constructor is deprecated because its meaning is ambiguous and variable across compilers and compiler versions.

This diff codemods uses of that constructor to use `folly::dynamic::array<...>(...)` instead.

This codemod may not get 100%, but that's okay. Any amount helps.

Reviewed By: ot

Differential Revision: D4013979

fbshipit-source-id: c6873dbc8027b38e71a0f291466ed2d9bd204a53

Summary:
- Annotate non-`const` static locals in inline functions which don't require
  a single copy be used globally at runtime.
- Move implmentation from header file to source file (to avoid multiple
  copies at runtime).
- Mark a non-stateful static local as `const` to it easy to ignore when
  searching for problematic static locals.

Reviewed By: yfeldblum

Differential Revision: D4010101

fbshipit-source-id: 3be94a5dc5b7029a26e11b2145c0d41968979a5c

Summary:
Some platforms do not output anything when `std::terminate` is called; this
fixes the test on those platforms.

Reviewed By: yfeldblum, jsedgwick

Differential Revision: D4001052

fbshipit-source-id: 671fbca9d6d22e372189b6554440c268c0cff60b