Commit Graph

87 Commits

Author SHA1 Message Date
Frederich Munch fd96d5e1c9 Revert "Refactor DynamicLibrary so searching for a symbol will have a defined order"
The i686-mingw32-RA-on-linux bot is still having errors.

This reverts commit r301236.

llvm-svn: 301240
2017-04-24 20:16:01 +00:00
Frederich Munch 70c377a362 Refactor DynamicLibrary so searching for a symbol will have a defined order and
libraries are properly unloaded when llvm_shutdown is called.

Summary:
This was mostly affecting usage of the JIT, where storing the library handles in
a set made iteration unordered/undefined. This lead to disagreement between the
JIT and native code as to what the address and implementation of particularly on
Windows with stdlib functions:

JIT: putenv_s("TEST", "VALUE") // called msvcrt.dll, putenv_s
JIT: getenv("TEST") -> "VALUE" // called msvcrt.dll, getenv
Native: getenv("TEST") -> NULL // called ucrt.dll, getenv

Also fixed is the issue of DynamicLibrary::getPermanentLibrary(0,0) on Windows
not giving priority to the process' symbols as it did on Unix.

Reviewers: chapuni, v.g.vassilev, lhames

Reviewed By: lhames

Subscribers: danalbert, srhines, mgorny, vsk, llvm-commits

Differential Revision: https://reviews.llvm.org/D30107

llvm-svn: 301236
2017-04-24 19:55:16 +00:00
Frederich Munch b8c236a6e4 Revert "Refactor DynamicLibrary so searching for a symbol will have a defined order.”
The changes are causing the i686-mingw32 build to fail.

This reverts commit r301153, and the changes for a separate warning on i686-mingw32 in r301155  and r301156.

llvm-svn: 301157
2017-04-24 03:33:30 +00:00
Frederich Munch 9f40457d61 Refactor DynamicLibrary so searching for a symbol will have a defined order and
libraries are properly unloaded when llvm_shutdown is called.

Summary:
This was mostly affecting usage of the JIT, where storing the library handles in
a set made iteration unordered/undefined. This lead to disagreement between the
JIT and native code as to what the address and implementation of particularly on
Windows with stdlib functions:

JIT: putenv_s("TEST", "VALUE") // called msvcrt.dll, putenv_s
JIT: getenv("TEST") -> "VALUE" // called msvcrt.dll, getenv
Native: getenv("TEST") -> NULL // called ucrt.dll, getenv

Also fixed is the issue of DynamicLibrary::getPermanentLibrary(0,0) on Windows
not giving priority to the process' symbols as it did on Unix.

Reviewers: chapuni, v.g.vassilev, lhames

Reviewed By: lhames

Subscribers: danalbert, srhines, mgorny, vsk, llvm-commits

Differential Revision: https://reviews.llvm.org/D30107

llvm-svn: 301153
2017-04-24 02:30:12 +00:00
Peter Collingbourne d1eac7bc36 Support: Add a cache pruning policy parser.
The idea is that the policy string fully specifies the policy and is portable
between clients.

Differential Revision: https://reviews.llvm.org/D31020

llvm-svn: 297927
2017-03-16 03:42:00 +00:00
Zachary Turner d9dc2829ea [Support] Move Stream library from MSF -> Support.
After several smaller patches to get most of the core improvements
finished up, this patch is a straight move and header fixup of
the source.

Differential Revision: https://reviews.llvm.org/D30266

llvm-svn: 296810
2017-03-02 20:52:51 +00:00
Eric Fiselier 87c87f4c30 [CMake] Fix pthread handling for out-of-tree builds
LLVM defines `PTHREAD_LIB` which is used by AddLLVM.cmake and various projects
to correctly link the threading library when needed. Unfortunately
`PTHREAD_LIB` is defined by LLVM's `config-ix.cmake` file which isn't installed
and therefore can't be used when configuring out-of-tree builds. This causes
such builds to fail since `pthread` isn't being correctly linked.

This patch attempts to fix that problem by renaming and exporting
`LLVM_PTHREAD_LIB` as part of`LLVMConfig.cmake`. I renamed `PTHREAD_LIB`
because It seemed likely to cause collisions with downstream users of
`LLVMConfig.cmake`.

llvm-svn: 294690
2017-02-10 01:59:20 +00:00
Sam Parker df7c6ef96f [ARM] Create objdump subtarget from build attrs
Enable an ELFObjectFile to read the its arm build attributes to
produce a target triple with a specific ARM architecture.
llvm-objdump now uses this functionality to automatically produce
a more accurate target.

Differential Revision: https://reviews.llvm.org/D28769

llvm-svn: 292366
2017-01-18 13:52:12 +00:00
Ivan Krasin 1ed7896c1b Revert r291903 and r291898. Reason: they break check-lld on the bots.
Summary:
Revert [ARM] Fix ubig32_t read in ARMAttributeParser

Now using support functions to read data instead of trying to
perform casts.
===========================================================

Revert [ARM] Enable objdump to construct triple for ARM

Now that The ARMAttributeParser has been moved into the library,
it has been modified so that it can parse the attributes without
printing them and stores them in a map. ELFObjectFile now queries
the attributes to fill out the architecture details of a provided
triple for 'arm' and 'thumb' targets. llvm-objdump uses this new
functionality.

Subscribers: llvm-commits, samparker, aemerson, mgorny

Differential Revision: https://reviews.llvm.org/D28683

llvm-svn: 291911
2017-01-13 16:45:15 +00:00
Sam Parker 770ceb69ba [ARM] Enable objdump to construct triple for ARM
Now that The ARMAttributeParser has been moved into the library,
it has been modified so that it can parse the attributes without
printing them and stores them in a map. ELFObjectFile now queries
the attributes to fill out the architecture details of a provided
triple for 'arm' and 'thumb' targets. llvm-objdump uses this new
functionality.

Differential Revision: https://reviews.llvm.org/D28281

llvm-svn: 291898
2017-01-13 11:04:21 +00:00
Rui Ueyama e9d17545bc TarWriter: Fix a bug in Ustar header.
If we split a filename into `Name` and `Prefix`, `Prefix` is at most
145 bytes. We had a bug that didn't split a path correctly. This bug
was pointed out by Rafael in the post commit review.

This patch adds a unit test for TarWriter to verify the fix.

llvm-svn: 291494
2017-01-09 22:55:00 +00:00
Eugene Leviant c089e406b9 Allow setting multiple debug types
Differential revision: https://reviews.llvm.org/D28109

llvm-svn: 290597
2016-12-27 09:31:20 +00:00
Rui Ueyama f7a7ab59af Move GlobPattern class from LLD to llvm/Support.
GlobPattern is a class to handle glob pattern matching. Currently
only LLD is using that, but technically that feature is not specific
to linkers, so in this patch I move that file to LLVM.

Differential Revision: https://reviews.llvm.org/D27969

llvm-svn: 290212
2016-12-20 23:09:09 +00:00
Ivan Krasin 3dade419bf Use trigrams to speed up SpecialCaseList.
Summary:
it's often the case when the rules in the SpecialCaseList
are of the form hel.o*bar. That gives us a chance to build
trigram index to quickly discard 99% of inputs without
running a full regex. A similar idea was used in Google Code Search
as described in the blog post:
https://swtch.com/~rsc/regexp/regexp4.html

The check is defeated, if there's at least one regex
more complicated than that. In this case, all inputs
will go through the regex. That said, the real-world
rules are often simple or can be simplied. That considerably
speeds up compiling Chromium with CFI and UBSan.

As measured on Chromium's content_message_generator.cc:

before, CFI: 44 s
after, CFI: 23 s
after, CFI, no blacklist: 23 s (~1% slower, but 3 runs were unable to show the difference)
after, regular compilation to bitcode: 23 s

Reviewers: pcc

Subscribers: mgorny, llvm-commits

Differential Revision: https://reviews.llvm.org/D27188

llvm-svn: 288303
2016-12-01 02:54:54 +00:00
Pavel Labath 0c20e05e89 Remove TimeValue class
Summary:
All uses have been replaced by appropriate std::chrono types, and the class is
now unused.

Reviewers: zturner, mehdi_amini

Subscribers: llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D26447

llvm-svn: 287094
2016-11-16 10:46:48 +00:00
Zachary Turner 11db2642fb [Support] Introduce llvm::formatv() function.
This introduces a new type-safe general purpose formatting
library.  It provides compile-time type safety, does not require
a format specifier (since the type is deduced), and provides
mechanisms for extending the format capability to user defined
types, and overriding the formatting behavior for existing types.

This patch additionally adds documentation for the API to the
LLVM programmer's manual.

Mailing List Thread:
http://lists.llvm.org/pipermail/llvm-dev/2016-October/105836.html

Differential Revision: https://reviews.llvm.org/D25587

llvm-svn: 286682
2016-11-11 23:57:40 +00:00
Peter Collingbourne 4e76019e34 Support: Remove MemoryObject and DataStreamer interfaces.
These interfaces are no longer used.

Differential Revision: https://reviews.llvm.org/D26222

llvm-svn: 285774
2016-11-02 00:08:37 +00:00
Zachary Turner 5b2243e884 Resubmit "Add support for advanced number formatting."
This resubmits r284436 and r284437, which were reverted in
r284462 as they were breaking the AArch64 buildbot.

The breakage on AArch64 turned out to be a miscompile which is
still not fixed, but is actively tracked at llvm.org/pr30748.

This resubmission re-writes the code in a way so as to make the
miscompile not happen.

llvm-svn: 285483
2016-10-29 00:27:22 +00:00
Pavel Labath 59838f7ea6 Reapply "Add Chrono.h - std::chrono support header"
This is a resubmission of r284590. The mingw build should be fixed now. The
problem was we were matching time_t with _localtime_64s, which was incorrect on
_USE_32BIT_TIME_T systems. Instead I use localtime_s, which should always
evaluate to the correct function.

llvm-svn: 284720
2016-10-20 12:05:50 +00:00
Pavel Labath 504f3844ae Revert "Add Chrono.h - std::chrono support header"
This reverts commit r284590 as it fails on the mingw buildbot. I think I know the
fix, but I cannot test it right now. Will reapply when I verify it works ok.

This reverts r284590.

llvm-svn: 284615
2016-10-19 17:17:53 +00:00
Pavel Labath 13b6a10e7b Add Chrono.h - std::chrono support header
Summary:
std::chrono mostly covers the functionality of llvm::sys::TimeValue and
lldb_private::TimeValue. This header adds a bit of utility functions and
typedefs, which make the usage of the library and porting code from TimeValues
easier.

Rationale:
- TimePoint typedef - precision of system_clock is implementation defined -
  using a well-defined precision helps maintain consistency between platforms,
  makes it interact better with existing TimeValue classes, and avoids cases
  there a time point is implicitly convertible to a specific precision on some
  platforms but not on others.
- system_clock::to_time_t only accepts time_points with the default system
  precision (even though time_t has only second precision on all platforms we
  support). To avoid the need for explicit casts, I have added a toTimeT()
  wrapper function. toTimePoint(time_t) was not strictly necessary, but I have
  added it for symmetry.

Reviewers: zturner, mehdi_amini

Subscribers: beanz, mgorny, llvm-commits, modocache

Differential Revision: https://reviews.llvm.org/D25416

llvm-svn: 284590
2016-10-19 13:58:55 +00:00
Renato Golin 9ce5074d29 Revert "Resubmit "Add support for advanced number formatting.""
This reverts commits 284436 and 284437 because they still break AArch64 bots:

Value of: format_number(-10, IntegerStyle::Integer, 1)
  Actual: "-0"
  Expected: "-10"

llvm-svn: 284462
2016-10-18 09:30:18 +00:00
Zachary Turner 7cd0745c95 Resubmit "Add support for advanced number formatting."
This resubmits commits 284425 and r284428, which were reverted
in r284429 due to some infinite recursion caused by an incorrect
selection of function overloads.  Reproduced the failure on Linux
using GCC 4.8.4, and confirmed that with the new patch the tests
path on GCC as well as MSVC.  So hopefully this fixes everything.

llvm-svn: 284436
2016-10-17 22:49:24 +00:00
Zachary Turner 9d58e362d2 Revert formatting changes.
This reverts r288425 and r284428 as they are causing test crashes
on some systems.

llvm-svn: 284429
2016-10-17 21:25:41 +00:00
Zachary Turner 99eef2d736 [Support] Add support for "advanced" number formatting.
raw_ostream has not afforded a lot of flexibility in terms of
how to format numbers when outputting.  Wrap this all up into
a set of low level helper functions that can be used to output
numbers with arbitrary precision, alignment, format, etc and
then update raw_ostream to use these functions.

This will be useful for upcoming improvements to llvm's string
formatting libraries, but are still useful independently.

Differential Revision: https://reviews.llvm.org/D25497

llvm-svn: 284425
2016-10-17 20:57:45 +00:00
Teresa Johnson 2bd812c5dc Add interface for querying physical hardware concurrency
Summary:
This will be used by ThinLTO to set the amount of backend
parallelism, which performs better when restricted to the number
of physical cores (on X86 at least, where getHostNumPhysicalCores is
currently defined). If not available this falls back to
thread::hardware_concurrency.

Note I didn't add to the thread class since that is a typedef to
std::thread where available.

Reviewers: mehdi_amini

Subscribers: beanz, llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D25585

llvm-svn: 284180
2016-10-14 00:13:59 +00:00
Teresa Johnson 7943fecee8 Add interface to compute number of physical cores on host system
Summary:
For now I have only added support for x86_64 Linux, but other systems
can be added incrementally.

This is to be used for setting the default parallelism for ThinLTO
backends (instead of thread::hardware_concurrency which includes
hyperthreading and is too aggressive). I'll send this as a follow-on
patch, and it will fall back to hardware_concurrency when the new
getHostNumPhysicalCores returns -1 (when not supported for a given
host system).

I also added an interface to MemoryBuffer to force reading a file
as a stream - this is required for /proc/cpuinfo which is a special
file that looks like a normal file but appears to have 0 size.
The existing readers of this file in Host.cpp are reading the first
1024 or so bytes from it, because the necessary info is near the top.
But for the new functionality we need to be able to read the entire
file. I can go back and change the other readers to use the new
getFileAsStream as a follow-on patch since it seems much more robust.

Added a unittest.

Reviewers: mehdi_amini

Subscribers: beanz, mgorny, llvm-commits, modocache

Differential Revision: https://reviews.llvm.org/D25564

llvm-svn: 284138
2016-10-13 17:43:20 +00:00
Rafael Espindola eaeb6d91a1 Add xxhash to llvm.
It will be used for fast fingerprinting in lld at least.

llvm-svn: 282493
2016-09-27 15:45:57 +00:00
Duncan P. N. Exon Smith 1bdc716dca Move unittests/Support/IteratorTest.cpp to unittests/ADT/
This testing stuff from ADT, not Support.  Fix the file location.

llvm-svn: 279372
2016-08-20 14:58:31 +00:00
Mehdi Amini 4cd5702578 Add support for computing SHA1 in LLVM
Provide a class to generate a SHA1 from a sequence of bytes, and
a convenience raw_ostream adaptor.
This will be used to provide a "build-id" by hashing the Module
block when writing bitcode. ThinLTO will use this information for
incremental build.

Reapply r265094 which was reverted in r265102 because it broke
MSVC bots (constexpr is not supported).

http://reviews.llvm.org/D16325

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265107
2016-04-01 04:30:16 +00:00
Mehdi Amini 85fb9e058e Revert "Add support for computing SHA1 in LLVM"
This reverts commit r265096, r265095, and r265094.
Windows build is broken, and the validation does not pass.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265102
2016-04-01 03:03:21 +00:00
Mehdi Amini 3689ae14eb Add support for computing SHA1 in LLVM
Provide a class to generate a SHA1 from a sequence of bytes, and
a convenience raw_ostream adaptor.
This will be used to provide a "build-id" by hashing the Module
block when writing bitcode. ThinLTO will use this information for
incremental build.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265094
2016-04-01 01:29:54 +00:00
Duncan P. N. Exon Smith 6648a0817e Support: Move StreamingMemoryObject{,Test}.cpp, NFC
Change the filename to indicate this is a test, rename the tests, move
them into an anonymous namespace, and rename some variables.  All to
match our usual style before making further changes.

llvm-svn: 264548
2016-03-27 22:55:19 +00:00
Lang Hames f7f6d3e93f [Support] Add the 'Error' class for structured error handling.
This patch introduces the Error classs for lightweight, structured,
recoverable error handling. It includes utilities for creating, manipulating
and handling errors. The scheme is similar to exceptions, in that errors are
described with user-defined types. Unlike exceptions however, errors are
represented as ordinary return types in the API (similar to the way
std::error_code is used).

For usage notes see the LLVM programmer's manual, and the Error.h header.
Usage examples can be found in unittests/Support/ErrorTest.cpp.

Many thanks to David Blaikie, Mehdi Amini, Kevin Enderby and others on the
llvm-dev and llvm-commits lists for lots of discussion and review.

llvm-svn: 263609
2016-03-16 01:02:46 +00:00
Saleem Abdulrasool 11bf1ac297 unitests: add some ARM TargetParser tests
The ARM TargetParser would construct invalid StringRefs.  This would cause
asserts to trigger.  Add some tests in LLVM to ensure that we dont regress on
this in the future.  Although there is a test for this in clang, this ensures
that the changes would get caught in the same repository.

llvm-svn: 262790
2016-03-06 04:50:55 +00:00
Rafael Espindola 5cd721ae12 Refactor duplicated code for linking with pthread.
llvm-svn: 262344
2016-03-01 15:54:40 +00:00
Chandler Carruth 17edbdd04c [Support] Add a fancy helper function to get a static name for a type.
This extracts the type name from __PRETTY_FUNCTION__ for compilers that
support it (I've opted Clang, GCC, and ICC into this as I've tested that
they work) and from __FUNCSIG__ which is very similar on MSVC. The
routine falls back gracefully on a stub "UNKNOWN_TYPE" string with
compilers or formats it doesn't understand.

This should be enough for a lot of common cases in LLVM where the real
goal is just to log or print a type name as a debugging aid, and save
a ton of boilerplate in the process. Notably, I'm planning to use this
to remove all the getName() boiler plate from the new pass manager.

The design and implementation is based on a bunch of advice and
discussion with Richard Smith and experimenting with most versions of
Clang and GCC. David Majnemer also provided excellent advice on how best
to do this with MSVC. Richard also checked that ICC does something
reasonable and I'll watch the build bots for other compilers. It'd be
great if someone could contribute logic for xlC and/or other toolchains.

Differential Revision: http://reviews.llvm.org/D17565

llvm-svn: 261819
2016-02-25 03:58:21 +00:00
Reid Kleckner 17495274fd [unittests] Move TargetRegistry test from Support to MC
This removes the dependency from SupportTests to all of the LLVM
backends, and makes it link faster.

llvm-svn: 259705
2016-02-03 21:41:24 +00:00
Vedant Kumar d167586a28 [Support] Allow multiple paired calls to {start,stop}Timer()
Differential Revision: http://reviews.llvm.org/D15619

Reviewed-by: rafael
llvm-svn: 256258
2015-12-22 17:36:17 +00:00
Mehdi Amini 33a7ea4b9a Add a C++11 ThreadPool implementation in LLVM
This is a very simple implementation of a thread pool using C++11
thread. It accepts any std::function<void()> for asynchronous
execution. Individual task can be synchronize using the returned
future, or the client can block on the full queue completion.

In case LLVM is configured with Threading disabled, it falls back
to sequential execution using std::async with launch:deferred.

This is intended to support parallelism for ThinLTO processing in
linker plugin, but is generic enough for any other uses.

This is a recommit of r255444 ; trying to workaround a bug in the
MSVC 2013 standard library. I think I was hit by:

 http://connect.microsoft.com/VisualStudio/feedbackdetail/view/791185/std-packaged-task-t-where-t-is-void-or-a-reference-class-are-not-movable

Recommit of r255589, trying to please g++ as well.

Differential Revision: http://reviews.llvm.org/D15464

From: mehdi_amini <mehdi_amini@91177308-0d34-0410-b5e6-96231b3b80d8>
llvm-svn: 255593
2015-12-15 00:59:19 +00:00
Mehdi Amini 2bc6a5ad84 Revert "Add a C++11 ThreadPool implementation in LLVM"
This reverts commit r255589. Breaks g++

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 255591
2015-12-15 00:42:44 +00:00
Mehdi Amini ef0ef2860d Add a C++11 ThreadPool implementation in LLVM
This is a very simple implementation of a thread pool using C++11
thread. It accepts any std::function<void()> for asynchronous
execution. Individual task can be synchronize using the returned
future, or the client can block on the full queue completion.

In case LLVM is configured with Threading disabled, it falls back
to sequential execution using std::async with launch:deferred.

This is intended to support parallelism for ThinLTO processing in
linker plugin, but is generic enough for any other uses.

This is a recommit of r255444 ; trying to workaround a bug in the
MSVC 2013 standard library. I think I was hit by:

 http://connect.microsoft.com/VisualStudio/feedbackdetail/view/791185/std-packaged-task-t-where-t-is-void-or-a-reference-class-are-not-movable

Differential Revision: http://reviews.llvm.org/D15464

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 255589
2015-12-15 00:38:05 +00:00
Nico Weber c2a687b6a6 Revert r255444.
It doesn't build on Windows and broke the Windows LLD and LLDB bots:
http://lab.llvm.org:8011/builders/lld-x86_64-win7/builds/27693/steps/build_Lld/logs/stdio
http://lab.llvm.org:8011/builders/lldb-x86-windows-msvc/builds/13468/steps/build/logs/stdio

llvm-svn: 255446
2015-12-13 04:14:39 +00:00
Mehdi Amini 396abbb6f0 Add a C++11 ThreadPool implementation in LLVM
This is a very simple implementation of a thread pool using C++11
thread. It accepts any std::function<void()> for asynchronous
execution. Individual task can be synchronize using the returned
future, or the client can block on the full queue completion.

In case LLVM is configured with Threading disabled, it falls back
to sequential execution using std::async with launch:deferred.

This is intended to support parallelism for ThinLTO processing in
linker plugin, but is generic enough for any other uses.

Differential Revision: http://reviews.llvm.org/D15464

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 255444
2015-12-12 22:55:25 +00:00
Greg Bedwell 7f68a71669 Fix rename() sometimes failing if another process uses openFileForRead()
On Windows, fs::rename() could fail is another process was reading the
file at the same time using fs::openFileForRead().  In most cases the user
wouldn't notice as fs::rename() will continue to retry for 2000ms.  Typically
this is enough for the read to complete and a retry to succeed, but if the
disk is being it too hard then the response time might be longer than the
retry time and the rename would fail with a permission error.

Add FILE_SHARE_DELETE to the sharing flags for CreateFileW() in
fs::openFileForRead() and try ReplaceFileW() prior to MoveFileExW()
in fs::rename().

Based on an initial patch by Edd Dawson!

Differential Revision: http://reviews.llvm.org/D13647

llvm-svn: 250046
2015-10-12 15:11:47 +00:00
James Y Knight aa365b2fcd Add a TrailingObjects template class.
This is intended to help support the idiom of a class that has some
other objects (or multiple arrays of different types of objects)
appended on the end, which is used quite heavily in clang.

Differential Revision: http://reviews.llvm.org/D11272

llvm-svn: 244164
2015-08-05 22:57:34 +00:00
Douglas Katzman ec1fc97e5d Prevent further errors of omission when adding backend names.
Differential Revision: http://reviews.llvm.org/D9441

llvm-svn: 236865
2015-05-08 15:34:12 +00:00
Rafael Espindola 37b7015916 Add raw_pwrite_stream type.
This is a raw_ostream that also supports pwrite.
I will be used in a sec.

llvm-svn: 234895
2015-04-14 15:00:34 +00:00
Matt Arsenault d931642cc7 Add support for double / float to EndianStream
Also add new unit tests for endian::Writer

llvm-svn: 228269
2015-02-05 03:30:08 +00:00
Duncan P. N. Exon Smith b036f1c98c Support: Stop stringifying DW_TAG_{lo,hi}_user
`dwarf::TagString()` shouldn't stringify `DW_TAG_lo_user` or
`DW_TAG_hi_user`.  These aren't actual tags; they're markers for the
edge of vendor-specific tag regions.

llvm-svn: 228029
2015-02-03 21:08:33 +00:00