Commit Graph

392 Commits

Author SHA1 Message Date
serge-sans-paille e188aae406 Cleanup header dependencies in LLVMCore
Based on the output of include-what-you-use.

This is a big chunk of changes. It is very likely to break downstream code
unless they took a lot of care in avoiding hidden ehader dependencies, something
the LLVM codebase doesn't do that well :-/

I've tried to summarize the biggest change below:

- llvm/include/llvm-c/Core.h: no longer includes llvm-c/ErrorHandling.h
- llvm/IR/DIBuilder.h no longer includes llvm/IR/DebugInfo.h
- llvm/IR/IRBuilder.h no longer includes llvm/IR/IntrinsicInst.h
- llvm/IR/LLVMRemarkStreamer.h no longer includes llvm/Support/ToolOutputFile.h
- llvm/IR/LegacyPassManager.h no longer include llvm/Pass.h
- llvm/IR/Type.h no longer includes llvm/ADT/SmallPtrSet.h
- llvm/IR/PassManager.h no longer includes llvm/Pass.h nor llvm/Support/Debug.h

And the usual count of preprocessed lines:
$ clang++ -E  -Iinclude -I../llvm/include ../llvm/lib/IR/*.cpp -std=c++14 -fno-rtti -fno-exceptions | wc -l
before: 6400831
after:  6189948

200k lines less to process is no that bad ;-)

Discourse thread on the topic: https://llvm.discourse.group/t/include-what-you-use-include-cleanup

Differential Revision: https://reviews.llvm.org/D118652
2022-02-02 06:54:20 +01:00
Shao-Ce SUN ec501f15a8 [clang][CodeGen] Remove the signed version of createExpression
Fix a TODO. Remove the callers of this signed version and delete.

Reviewed By: CodaFi

Differential Revision: https://reviews.llvm.org/D116014
2021-12-27 14:16:08 +08:00
Kazu Hirata 87e53a0ad8 [llvm] Use make_early_inc_range (NFC) 2021-11-05 19:39:07 -07:00
Koutheir Attouchi 16661b1a3c Expose `DIBuilder::finalizeSubprogram()` through the LLVM C API
The LLVM C API function is called `LLVMDIBuilderFinalizeSubprogram()`.

Reviewed By: CodaFi

Differential Revision: https://reviews.llvm.org/D104794
2021-09-30 20:59:41 -07:00
Alok Kumar Sharma a5b72abc9e [DebugInfo] Enhance DIImportedEntity to accept children entities
New field `elements` is added to '!DIImportedEntity', representing
list of aliased entities.
This is needed to dump optimized debugging information where all names
in a module are imported, but a few names are imported with overriding
aliases.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D109343
2021-09-16 10:41:55 +05:30
Adrian Prantl fcfaed4ae6 Remove redundant comparisons (NFC) 2021-06-02 09:52:45 -07:00
Adrian Prantl f3869a5c32 Support stripping indirectly referenced DILocations from !llvm.loop metadata
in stripDebugInfo().  This patch fixes an oversight in
https://reviews.llvm.org/D96181 and also takes into account loop
metadata pointing to other MDNodes that point into the debug info.

rdar://78487175

Differential Revision: https://reviews.llvm.org/D103220
2021-05-27 13:23:33 -07:00
OCHyams 0ebf9a8e34 [DebugInfo] Move the findDbg* functions into DebugInfo.cpp
Move the findDbg* functions into lib/IR/DebugInfo.cpp from
lib/Transforms/Utils/Local.cpp.

D99169 adds a call to a function (findDbgUsers) that lives in
lib/Transforms/Utils/Local.cpp (LLVMTransformUtils) from lib/IR/Value.cpp
(LLVMCore). The Core lib doesn't include TransformUtils. The builtbots caught
this here: https://lab.llvm.org/buildbot/#/builders/109/builds/12664. This patch
moves the function, and the 3 similar ones for consistency, into DebugInfo.cpp
which is part of LLVMCore.

Reviewed By: dblaikie, rnk

Differential Revision: https://reviews.llvm.org/D100632
2021-04-19 10:30:25 +01:00
Adrian Prantl c3a18bb1e8 Support !heapallocsite attachments in StripDebugInfo().
They point into the DIType type system, so they need to be stripped as well.

rdar://75341300

Differential Revision: https://reviews.llvm.org/D98668
2021-03-16 10:05:13 -07:00
Adrian Prantl b04c87e053 Support !heapallocsite attachments in stripNonLineTableDebugInfo().
They point into the DIType type system, so they need to be stripped as well.

rdar://75341300

Differential Revision: https://reviews.llvm.org/D98667
2021-03-16 10:05:12 -07:00
Kazu Hirata b4bed1cb24 [IR] Use range-based for loops (NFC) 2021-02-28 10:59:23 -08:00
Adrian Prantl 79f46a30c2 Have stripDebugInfo() also strip !llvm.loop annotations from all
instructions.

The !llvm.loop annotations consist of pointers into the debug info, so
when stripping the debug info (particularly important when it is
malformed!) !llvm.loop annotations need to be stripped as well, or
else the malformed debug info stays around.  This patch applies the
stripping to all instructions, not just terminator instructions.

rdar://73687049

Differential Revision: https://reviews.llvm.org/D96181
2021-02-05 17:22:41 -08:00
Fangrui Song b5ad32ef5c Migrate deprecated DebugLoc::get to DILocation::get
This migrates all LLVM (except Kaleidoscope and
CodeGen/StackProtector.cpp) DebugLoc::get to DILocation::get.

The CodeGen/StackProtector.cpp usage may have a nullptr Scope
and can trigger an assertion failure, so I don't migrate it.

Reviewed By: #debug-info, dblaikie

Differential Revision: https://reviews.llvm.org/D93087
2020-12-11 12:45:22 -08:00
Vedant Kumar dfc5a9eb57 [Instruction] Add dropLocation and updateLocationAfterHoist helpers
Introduce a helper which can be used to update the debug location of an
Instruction after the instruction is hoisted. This can be used to safely
drop a source location as recommended by the docs.

For more context, see the discussion in https://reviews.llvm.org/D60913.

Differential Revision: https://reviews.llvm.org/D85670
2020-09-24 15:00:04 -07:00
Vedant Kumar 30c1633386 Revert "[Instruction] Add updateLocationAfterHoist helper"
This reverts commit 4a646ca9e2.

This is causing some bots to fail with "!dbg attachment points at wrong
subprogram for function", like:

http://lab.llvm.org:8011/builders/sanitizer-windows/builds/67958/steps/stage%201%20check/logs/stdio
2020-08-11 14:54:09 -07:00
Vedant Kumar 4a646ca9e2 [Instruction] Add updateLocationAfterHoist helper
Introduce a helper on Instruction which can be used to update the debug
location after hoisting.

Use this in GVN and LICM, where we were mistakenly introducing new line
0 locations after hoisting (the docs recommend dropping the location in
this case).

For more context, see the discussion in https://reviews.llvm.org/D60913.

Differential Revision: https://reviews.llvm.org/D85670
2020-08-11 14:05:20 -07:00
Simon Pilgrim 2c7af6dffc Pass stripNonLineTableDebugInfo remapDebugLoc lambda DebugLoc arg by const reference not value.
Noticed by clang-tidy performance-unnecessary-value-param warning.
2020-07-01 12:37:47 +01:00
Vedant Kumar 9350792c62 [DebugInfo] Update loop metadata in stripNonLineTableDebugInfo
Summary:
Have stripNonLineTableDebugInfo() attach updated !llvm.loop metadata to
an instruction (instead of updating and then discarding the metadata).

This fixes "!dbg attachment points at wrong subprogram for function"
errors seen while archiving an iOS app.

It would be nice -- as a follow-up -- to catch this issue earlier,
perhaps by modifying the verifier to constrain where DILocations are
allowed. Any alternative suggestions appreciated.

rdar://61982466

Reviewers: aprantl, dsanders

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D79200
2020-05-01 11:36:05 -07:00
Adrian Prantl 93fe58c9cf Teach the stripNonLineTableDebugInfo pass about the llvm.dbg.label intrinsic.
Debug info for labels is not generated at -gline-tables-only, so this
pass should remove them.

Differential Revision: https://reviews.llvm.org/D77345
2020-04-02 17:39:33 -07:00
Adrian Prantl c024f3ebdc Teach the stripNonLineTableDebugInfo pass about the llvm.dbg.addr intrinsic.
This patch also strips llvm.dbg.addr intrinsics when downgrading debug
info to linetables-only.

Differential Revision: https://reviews.llvm.org/D77343
2020-04-02 17:39:33 -07:00
Adrian Prantl d5180ea134 Add debug info support for Swift/Clang APINotes.
In order for dsymutil to collect .apinotes files (which capture
attributes such as nullability, Swift import names, and availability),
I want to propose adding an apinotes: field to DIModule that gets
translated into a DW_AT_LLVM_apinotes (path) nested inside
DW_TAG_module. This will be primarily used by LLDB to indirectly
extract the Swift names of Clang declarations that were deserialized
from DWARF.

<rdar://problem/59514626>

Differential Revision: https://reviews.llvm.org/D75585
2020-03-11 18:47:30 -07:00
Adrian Prantl e4e7e44765 Add an SDK attribute to DICompileUnit
This is part of PR44213 https://bugs.llvm.org/show_bug.cgi?id=44213

When importing (system) Clang modules, LLDB needs to know which SDK
(e.g., MacOSX, iPhoneSimulator, ...) they came from. While the sysroot
attribute contains the absolute path to the SDK, this doesn't work
well when the debugger is run on a different machine than the
compiler, and the SDKs are installed in different directories. It thus
makes sense to just store the name of the SDK instead of the absolute
path, so it can be found relative to LLDB.

rdar://problem/51645582

Differential Revision: https://reviews.llvm.org/D75646
2020-03-11 14:14:06 -07:00
Fangrui Song ecd2aaee06 [DebugInfo] Merge DebugInfoFinder::{processDeclare,processValue} into processVariable
The two functions are identical.
2020-02-01 23:00:21 -08:00
Adrian Prantl 7b30370e5b Move the sysroot attribute from DIModule to DICompileUnit
[this re-applies c0176916a4
 with the correct commit message and phabricator link]

This addresses point 1 of PR44213.
https://bugs.llvm.org/show_bug.cgi?id=44213

The DW_AT_LLVM_sysroot attribute is used for Clang module debug info,
to allow LLDB to import a Clang module from source. Currently it is
part of each DW_TAG_module, however, it is the same for all modules in
a compile unit. It is more efficient and less ambiguous to store it
once in the DW_TAG_compile_unit.

This should have no effect on DWARF consumers other than LLDB.

Differential Revision: https://reviews.llvm.org/D71732
2020-01-17 12:55:40 -08:00
Adrian Prantl c17aee67f1 Revert "Rename DW_AT_LLVM_isysroot to DW_AT_LLVM_sysroot"
This reverts commit 12e479475a.

I accidentally landed this patch with the wrong commit message ...
2020-01-17 12:52:36 -08:00
Adrian Prantl 12e479475a Rename DW_AT_LLVM_isysroot to DW_AT_LLVM_sysroot
This is a purely cosmetic change that is NFC in terms of the binary
output. I bugs me that I called the attribute DW_AT_LLVM_isysroot
since the "i" is an artifact of GCC command line option syntax
(-isysroot is in the category of -i options) and doesn't carry any
useful information otherwise.

This attribute only appears in Clang module debug info.

Differential Revision: https://reviews.llvm.org/D71722
2020-01-17 09:36:48 -08:00
Vedant Kumar a2cc80bc95 DebugInfo: Factor out logic to update locations in MD_loop metadata, NFC
Factor out the logic needed to update debug locations contained within
MD_loop metadata.

This refactor is preparation for a future change that also needs to
rewrite MD_loop metadata.

rdar://45507940
2020-01-15 13:02:36 -08:00
Yonghong Song e3d8ee35e4 reland "[DebugInfo] Support to emit debugInfo for extern variables"
Commit d77ae1552f
("[DebugInfo] Support to emit debugInfo for extern variables")
added deebugInfo for extern variables for BPF target.
The commit is reverted by 891e25b02d
as the committed tests using %clang instead of %clang_cc1 causing
test failed in certain scenarios as reported by Reid Kleckner.

This patch fixed the tests by using %clang_cc1.

Differential Revision: https://reviews.llvm.org/D71818
2019-12-22 18:28:50 -08:00
Reid Kleckner 891e25b02d Revert "[DebugInfo] Support to emit debugInfo for extern variables"
This reverts commit d77ae1552f.

The tests committed along with this change do not pass, and should be
changed to use %clang_cc1.
2019-12-22 12:54:06 -08:00
Adrian Prantl 44b4b833ad Rename DW_AT_LLVM_isysroot to DW_AT_LLVM_sysroot
This is a purely cosmetic change that is NFC in terms of the binary
output. I bugs me that I called the attribute DW_AT_LLVM_isysroot
since the "i" is an artifact of GCC command line option syntax
(-isysroot is in the category of -i options) and doesn't carry any
useful information otherwise.

This attribute only appears in Clang module debug info.

Differential Revision: https://reviews.llvm.org/D71722
2019-12-20 13:11:17 -08:00
Yonghong Song d77ae1552f [DebugInfo] Support to emit debugInfo for extern variables
Extern variable usage in BPF is different from traditional
pure user space application. Recent discussion in linux bpf
mailing list has two use cases where debug info types are
required to use extern variables:
  - extern types are required to have a suitable interface
    in libbpf (bpf loader) to provide kernel config parameters
    to bpf programs.
    https://lore.kernel.org/bpf/CAEf4BzYCNo5GeVGMhp3fhysQ=_axAf=23PtwaZs-yAyafmXC9g@mail.gmail.com/T/#t
  - extern types are required so kernel bpf verifier can
    verify program which uses external functions more precisely.
    This will make later link with actual external function no
    need to reverify.
    https://lore.kernel.org/bpf/87eez4odqp.fsf@toke.dk/T/#m8d5c3e87ffe7f2764e02d722cb0d8cbc136880ed

This patch added clang support to emit debuginfo for extern variables
with a TargetInfo hook to enable it. The debuginfo for the
extern variable is emitted only if that extern variable is
referenced in the current compilation unit.

Currently, only BPF target enables to generate debug info for
extern variables. The emission of such debuginfo is disabled for C++
 at this moment since BPF only supports a subset of C language.
Emission with C++ can be enabled later if an appropriate use case
is identified.

-fstandalone-debug permits us to see more debuginfo with the cost
of bloated binary size. This patch did not add emission of extern
variable debug info with -fstandalone-debug. This can be
re-evaluated if there is a real need.

Differential Revision: https://reviews.llvm.org/D70696
2019-12-10 08:09:51 -08:00
Sourabh Singh Tomar f1e3988aa6 Recommit "[DWARF5]Addition of alignment atrribute in typedef DIE."
This revision is revised to update Go-bindings and Release Notes.

The original commit message follows.

This patch, adds support for DW_AT_alignment[DWARF5] attribute, to be emitted with typdef DIE.
When explicit alignment is specified.

Patch by Awanish Pandey <Awanish.Pandey@amd.com>

Reviewers: aprantl, dblaikie, jini.susan.george, SouraVX, alok,
deadalinx

Differential Revision: https://reviews.llvm.org/D70111
2019-12-03 09:51:43 +05:30
Sam McCall d27a16eb39 Revert "[DWARF5]Addition of alignment atrribute in typedef DIE."
This reverts commit 423f541c1a, which
breaks llvm-c ABI.
2019-11-18 15:53:22 +01:00
Sourabh Singh Tomar 423f541c1a [DWARF5]Addition of alignment atrribute in typedef DIE.
This patch, adds support for DW_AT_alignment[DWARF5] attribute, to be emitted with typdef DIE.
When explicit alignment is specified.

Patch by Awanish Pandey <Awanish.Pandey@amd.com>

Reviewers: aprantl, dblaikie, jini.susan.george, SouraVX, alok,
deadalinx

Differential Revision: https://reviews.llvm.org/D70111
2019-11-16 21:56:53 +05:30
Jordan Rose fdaa742174 Second attempt to add iterator_range::empty()
Doing this makes MSVC complain that `empty(someRange)` could refer to
either C++17's std::empty or LLVM's llvm::empty, which previously we
avoided via SFINAE because std::empty is defined in terms of an empty
member rather than begin and end. So, switch callers over to the new
method as it is added.

https://reviews.llvm.org/D68439

llvm-svn: 373935
2019-10-07 18:14:24 +00:00
whitequark b63db94fa5 [LLVM-C] Add bindings to create macro debug info
Summary: The C API doesn't have the bindings to create macro debug information.

Reviewers: whitequark, CodaFi, deadalnix

Reviewed By: whitequark

Subscribers: aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58334

llvm-svn: 373903
2019-10-07 13:57:13 +00:00
Fangrui Song da82ce99b7 [DebugInfo] Delete TypedDINodeRef
TypedDINodeRef<T> is a redundant wrapper of Metadata * that is actually a T *.

Accordingly, change DI{Node,Scope,Type}Ref uses to DI{Node,Scope,Type} * or their const variants.
This allows us to delete many resolve() calls that clutter the code.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D61369

llvm-svn: 360108
2019-05-07 02:06:37 +00:00
Robert Widmann d909a5ed8d [LLVM-C] Add DIFile Field Accesssors
Summary:
Add accessors for the file, directory, source file name (curiously, an `Optional` value?), of a DIFile.

This is intended to replace the LLVMValueRef-based accessors used in D52239

Reviewers: whitequark, jberdine, deadalnix

Reviewed By: whitequark, jberdine

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60489

llvm-svn: 358577
2019-04-17 13:29:14 +00:00
Robert Widmann d6eb4bb801 [LLVM-C] Add Accessors For Global Variable Metadata Properties
Summary: Metadata for a global variable is really a  (GlobalVariable, Expression) tuple.  Allow access to these, then allow retrieving the file, scope, and line for a DIVariable, whether global or local.  This should be the last of the accessors required for uniform access to location and file information metadata.

Reviewers: jberdine, whitequark, deadalnix

Reviewed By: jberdine, whitequark

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60725

llvm-svn: 358532
2019-04-16 21:39:48 +00:00
Robert Widmann cce47418c9 [LLVM-C] Correct The Current Debug Location Accessors (Again)
Summary: Resubmitting D60484 with the conflicting Go bindings renamed to avoid collisions.

Reviewers: whitequark, deadalnix

Subscribers: hiraditya, llvm-commits, sammccall

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60511

llvm-svn: 358086
2019-04-10 14:19:05 +00:00
Robert Widmann bec0a45ddc [LLVM-C] Add Bindings to Access an Instruction's DebugLoc
Summary: Provide direct accessors to supplement LLVMSetInstDebugLocation.  In addition, properly accept and return the NULL location.  The old accessors provided no way to do this, so the current debug location cannot currently be cleared.

Reviewers: whitequark, deadalnix

Reviewed By: whitequark

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60481

llvm-svn: 358038
2019-04-09 22:27:51 +00:00
Robert Widmann a82b613c8d [LLVM-C] Add bindings to create enumerators
Summary: The C API don't have the bindings to create enumerators, needed to create an enumeration.

Reviewers: whitequark, CodaFi, harlanhaskins, deadalnix

Reviewed By: whitequark, CodaFi, harlanhaskins

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58323

llvm-svn: 354237
2019-02-17 21:25:47 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
David Blaikie ac69af7ad6 llvm-dwarfdump: Improve/fix pretty printing of array dimensions
This is to address post-commit feedback from Paul Robinson on r348954.

The original commit misinterprets count and upper bound as the same thing (I thought I saw GCC producing an upper bound the same as Clang's count, but GCC correctly produces an upper bound that's one less than the count (in C, that is, where arrays are zero indexed)).

I want to preserve the C-like output for the common case, so in the absence of a lower bound the count (or one greater than the upper bound) is rendered between []. In the trickier cases, where a lower bound is specified, a half-open range is used (eg: lower bound 1, count 2 would be "[1, 3)" and an unknown parts use a '?' (eg: "[1, ?)" or "[?, 7)" or "[?, ? + 3)").

Reviewers: aprantl, probinson, JDevlieghere

Differential Revision: https://reviews.llvm.org/D55721

llvm-svn: 349670
2018-12-19 19:34:24 +00:00
Paul Robinson cda5421016 [DebugInfo] DISubprogram flags get their own flags word. NFC.
This will hold flags specific to subprograms. In the future
we could potentially free up scarce bits in DIFlags by moving
subprogram-specific flags from there to the new flags word.

This patch does not change IR/bitcode formats, that will be
done in a follow-up.

Differential Revision: https://reviews.llvm.org/D54597

llvm-svn: 347239
2018-11-19 18:29:28 +00:00
David Blaikie bb279116f2 DebugInfo: Add a CU metadata attribute for use of DWARF ranges base address specifiers
Summary:
Ranges base address specifiers can save a lot of object size in
relocation records especially in optimized builds.

For an optimized self-host build of Clang with split DWARF and debug
info compression in object files, but uncompressed debug info in the
executable, this change produces about 18% smaller object files and 6%
larger executable.

While it would've been nice to turn this on by default, gold's 32 bit
gdb-index support crashes on this input & I don't think there's any
perfect heuristic to implement solely in LLVM that would suffice - so
we'll need a flag one way or another (also possible people might want to
aggressively optimized for executable size that contains debug info
(even with compression this would still come at some cost to executable
size)) - so let's plumb it through.

Differential Revision: https://reviews.llvm.org/D54242

llvm-svn: 346788
2018-11-13 20:08:10 +00:00
Matthias Braun 9fd397b423 ADT/STLExtras: Introduce llvm::empty; NFC
This is modeled after C++17 std::empty().

Differential Revision: https://reviews.llvm.org/D53909

llvm-svn: 345679
2018-10-31 00:23:23 +00:00
Matthew Voss f8ab35a4f4 Emit template type and value parameter DIEs for template variables.
Summary:
Ensure the TemplateParam attribute of the DIGlobalVariable node is translated into the proper DIEs.

Resolves https://bugs.llvm.org/show_bug.cgi?id=22119

Reviewers: dblaikie, probinson, aprantl, JDevlieghere, clayborg, whitequark, deadalnix

Reviewed By: dblaikie

Subscribers: llvm-commits

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D52057

llvm-svn: 343706
2018-10-03 18:44:53 +00:00
Robert Widmann abda7ee8e7 [LLVM-C] Add an accessor for the kind of a Metadata Node
Summary: Allows for retrieving the type of a metadata node.  Has the added benefit of ensuring that the C and C++ kind APIs stay in sync as a failure to add a corresponding LLVMMetadataKind will result in the switch in the accessor being semantically malformed.

Reviewers: whitequark, deadalnix

Reviewed By: whitequark

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D52693

llvm-svn: 343469
2018-10-01 13:15:09 +00:00
Robert Widmann 106eab0292 [C-API][DIBuilder] Use NameLen in LLVMDIBuilderCreateParameterVariable
Summary: NameLen wasn't being used and caused the parameters in gdb to very long, in my case, crashes in others. Please also perform the correct magical incarnations to have this be applied to the LLVM 7 branch.

Reviewers: whitequark, CodaFi

Reviewed By: CodaFi

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D51141

llvm-svn: 340691
2018-08-25 19:54:39 +00:00