Commit Graph

2113 Commits

Author SHA1 Message Date
Kevin Enderby
ea32ab98f4 Tweak the MCExternalSymbolizer to print references to C string literals
with raw_ostream's write_escaped() method.

For example darwin's otool(1) program that uses the llvm
disassembler now produces disassembly like this:

leaq	0x7b(%rip), %rdi ## literal pool for: "%f\ntoto\n"

and not print the new lines which messes up the output.

rdar://15145300


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199407 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-16 18:43:56 +00:00
Rafael Espindola
640f8f65a7 Add an emitRawComment function and use it to simplify some uses of EmitRawText.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199397 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-16 16:28:37 +00:00
Rafael Espindola
9dcfdf61a8 CommentColumn is always 40. Simplify.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199357 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-16 07:04:11 +00:00
David Peixotto
a034c96443 Fix parsing of .symver directive on ARM
ARM assembly syntax uses @ for a comment, execpt for the second
parameter of the .symver directive which requires @ as part of the
symbol name. This commit fixes the parsing of this directive by
adding a special case for ARM for this one argumnet.

To make the change we had to move the AllowAtInIdentifier variable
to the MCAsmLexer interface (from AsmLexer) and expose a setter for
the value.  The ELFAsmParser then toggles this value when parsing
the second argument to the .symver directive for a target that
uses @ as a comment symbol


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199339 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-15 22:40:02 +00:00
Rafael Espindola
3c733ea064 Replace .mips_hack_stocg with ".set micromips" and ".set nomicromips".
This matches what gnu as does and implementing this is easier than arguing
about it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199181 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-14 04:25:13 +00:00
Joerg Sonnenberger
286cc13546 Fix indentation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199118 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-13 15:50:36 +00:00
David Blaikie
0f09c9f5ac Revert "Revert r198851, "Prototype of skeleton type units for fission""
This reverts commit r198865 which reverts r198851.

ASan identified a use-of-uninitialized of the DwarfTypeUnit::Ty variable
in skeleton type units.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198908 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-10 01:38:41 +00:00
NAKAMURA Takumi
adff827c6a Revert r198851, "Prototype of skeleton type units for fission"
It caused undefined behavior. DwarfTypeUnit::Ty might not be initialized properly, I guess.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198865 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-09 13:08:00 +00:00
David Blaikie
5f0929577b Prototype of skeleton type units for fission
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198851 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-09 05:08:28 +00:00
Roman Divacky
edc4b60fca Force emit a relocation for @gnu_indirect_function symbols so that the indirect
resolution works.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198780 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-08 18:50:32 +00:00
Iain Sandoe
9c0a05c7af [patch] Adjust behavior of FDE cross-section relocs for targets that don't support abs-differences.
Modern versions of OSX/Darwin's ld (ld64 > 97.17) have an optimisation present that allows the back end to omit relocations (and replace them with an absolute difference) for FDE some text section refs.

This patch allows a backend to opt-in to this behaviour by setting "DwarfFDESymbolsUseAbsDiff".  At present, this is only enabled for modern x86 OSX ports.

test changes by David Fang.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198744 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-08 10:22:54 +00:00
Roman Divacky
7e889af768 In the ELFWriter when writing aliased (.set) symbols dont blindly
take type from the new symbol but merge them so that the type
is never "downgraded".

This is probably quite rare, except for IFUNC symbols which
we used to misassemble, losing the IFUNC type.

Fixes #18372.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198706 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-07 20:17:03 +00:00
Chandler Carruth
974a445bd9 Re-sort all of the includes with ./utils/sort_includes.py so that
subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.

Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198685 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-07 11:48:04 +00:00
Saleem Abdulrasool
307f17b938 MCParser: introduce Note and use it for ARM AsmParser
Introduce a new virtual method Note into the AsmParser.  This completements the
existing Warning and Error methods.  Use the new method to clean up the output
of the unwind routines in the ARM AsmParser.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198661 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-07 02:28:31 +00:00
Kevin Enderby
284c8bc4b0 For the 'C' disassembler API, add a new ReferenceType for the
SymbolLookUp() call back to return a demangled C++ name to
be used as a comment.

For example darwin's otool(1) program the uses the llvm
disassembler now can produce disassembly like:

callq   __ZNK4llvm6Target20createMCDisassemblerERKNS_15MCSubtargetInfoE ## llvm::Target::createMCDisassembler(llvm::MCSubtargetInfo const&) const

Also fix a bug in LLVMDisasmInstruction() that was not flushing
the raw_svector_ostream for the disassembled instruction string
before copying it to the output buffer that was causing truncation
of the output.

rdar://10173828


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198637 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-06 22:08:08 +00:00
David Majnemer
ba7548302b MC: Fatally error if subtraction operand is bad
Instead of crashing, raise an error when a subtraction expression
involves an undefined symbol.

This fixes PR18375.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198590 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-06 07:39:46 +00:00
Reid Kleckner
077b7b1472 Revert "For disassembly when adding a symbolic operand that is a C++ symbol name, also put the human readable name in a comment."
This reverts commit r198441.

This change doesn't build on Windows, and doesn't do the right thing on
Linux and other platforms that don't use a _Z prefix instead of __Z for
C++ names.

It also had no tests, so it wasn't clear how to fix it forward.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198445 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-03 19:56:20 +00:00
Kevin Enderby
6cedb06492 For disassembly when adding a symbolic operand that is a C++
symbol name, also put the human readable name in a comment.

Also fix a bug in LLVMDisasmInstruction() that was not flushing
the raw_svector_ostream for the disassembled instruction string
before copying it to the output buffer that was causing truncation
of the output.

rdar://10173828


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198441 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-03 19:33:09 +00:00
Rafael Espindola
8e0f67dcec Make the llvm mangler depend only on DataLayout.
Before this patch any program that wanted to know the final symbol name of a
GlobalValue had to link with Target.

This patch implements a compromise solution where the mangler uses DataLayout.
This way, any tool that already links with Target (llc, clang) gets the exact
behavior as before and new IR files can be mangled without linking with Target.

With this patch the mangler is constructed with just a DataLayout and DataLayout
is extended to include the information the Mangler needs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198438 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-03 19:21:54 +00:00
Saleem Abdulrasool
14b42a1c92 AsmParser: cleanup diagnostics for .rep/.rept
Avoid double diagnostics for invalid expressions for count.  Improve caret
location for negative count.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198099 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-28 06:39:29 +00:00
Saleem Abdulrasool
b5191e98e8 IAS: support .rep as an alias for .rept
The GNU assembler supports .rep as an alias for .rept.  This simply creates the
alias for it and introduces a test for both .rept and .rep.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198097 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-28 05:54:33 +00:00
Timur Iskhodzhanov
93c53f4d24 clang-format a couple of mis-formatted functions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197831 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-20 20:16:51 +00:00
Timur Iskhodzhanov
8aa3ff05c1 [COFF] Add support for the .secidx directive
Reviewed at http://llvm-reviews.chandlerc.com/D2445

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197826 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-20 18:15:00 +00:00
David Peixotto
6075fa1e0e Add a finishParse() callback to the targer asm parser
This callback is invoked when the parse has finished successfuly. It
will be used to write out ARM constant pools to implement the ldr
pseudo.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197706 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-19 18:08:08 +00:00
Saleem Abdulrasool
5a445395de AsmParser: add support for .end directive
The .end directive indicates the end of the file.  No further instructions are
processed after a .end directive is encountered.

One potential (glaringly obvious) optimisation that could be pursued here is to
extend MCAsmParser with a DiscardRemainder method to avoid processing lexemes to
the end of the file.  It was unclear at this point if that would be worth
adding, and could easily be added in a follow on change.

Signed-off-by: Saleem Abdulrasool <compnerd@compnerd.org>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197547 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-18 02:53:03 +00:00
Reid Kleckner
65c4329181 MC COFF: Emit the 'b' section flag for .bss sections in GNU assembly
Without this, assembling clang's disassembly would produce an object
file with the IMAGE_SCN_CNT_INITIALIZED_DATA section characteristic
rather than the uninitialized one.  link.exe would warn when merging
comdats with different flags.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197529 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-17 22:12:40 +00:00
David Blaikie
5c9e0e52da DebugInfo: Move type units into the debug_types section with appropriate comdat grouping and type unit headers
This commit does not complete the type units feature - there are issues
around fission support (skeletal type units, pubtypes/pubnames) and
hashing of some types including those containing references to types in
other type units.

Originally committed as r197073 and reverted in r197079.
Recommitted as r197197 to reproduce the failure and reverted as r197199

Turns out there was unstable ordering in the type unit dumping code.
Fixed by using MapVector in DWARFContext to store the debug_types
comdat sections.

Recommitted as r197210 with a fix to dumping and reverted as r197211
because I was a bit gun shy and thought I saw a failure that turned out
to be unrelated.

So here we go - once more with feeling! \o/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197275 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-13 21:33:40 +00:00
David Blaikie
2d39ad82bc Revert "DebugInfo: Move type units into the debug_types section with appropriate comdat grouping and type unit headers"
This reverts commit r197210.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197211 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-13 06:43:32 +00:00
David Blaikie
bc6b250c74 DebugInfo: Move type units into the debug_types section with appropriate comdat grouping and type unit headers
This commit does not complete the type units feature - there are issues
around fission support (skeletal type units, pubtypes/pubnames) and
hashing of some types including those containing references to types in
other type units.

Originally committed as r197073 and reverted in r197079.
Recommitted as r197197 to reproduce the failure and reverted as r197199

Turns out there was unstable ordering in the type unit dumping code.
Fixed by using MapVector in DWARFContext to store the debug_types
comdat sections.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197210 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-13 06:27:38 +00:00
David Blaikie
8290d175ff Revert "DebugInfo: Move type units into the debug_types section with appropriate comdat grouping and type unit headers"
This reverts commit r197197.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197199 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-13 01:24:54 +00:00
David Blaikie
f4597a0cd4 DebugInfo: Move type units into the debug_types section with appropriate comdat grouping and type unit headers
This commit does not complete the type units feature - there are issues
around fission support (skeletal type units, pubtypes/pubnames) and
hashing of some types including those containing references to types in
other type units.

Originally committed as r197073 and reverted in r197079.

This commit originally got jumbled up with another build-breaking commit
and I can't find the failures I thought this caused anymore.
Recommitting to hopefully get some clean buildbot results to work from.
I have a sneaking suspicion there's unstable output in the comdat group
output of MCStreamer...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197197 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-13 01:06:41 +00:00
David Blaikie
118de30ec1 Revert "DebugInfo: Move type units into the debug_types section with appropriate comdat grouping and type unit headers"
This reverts commit r197073.

The test seems to be failing on some buildbots for unknown reasons.
Reverting until I can figure that out. If anyone's got a reproduction
(.s and .o together would be great) - I'd really appreciate it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197079 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-11 22:08:39 +00:00
David Blaikie
3d2670cc54 DebugInfo: Move type units into the debug_types section with appropriate comdat grouping and type unit headers
This commit does not complete the type units feature - there are issues
around fission support (skeletal type units, pubtypes/pubnames) and
hashing of some types including those containing references to types in
other type units.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197073 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-11 21:36:27 +00:00
NAKAMURA Takumi
0d87d72fa7 Prune redundant dependencies in LLVMBuild.txt.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196988 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-11 00:30:57 +00:00
David Fang
b59d46efa5 on darwin<10, fallback to .weak_definition (PPC,X86)
.weak_def_can_be_hidden was not yet supported by the system assembler

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196970 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-10 21:37:41 +00:00
Reid Kleckner
7c30637b0e Reland "Fix miscompile of MS inline assembly with stack realignment"
This re-lands commit r196876, which was reverted in r196879.

The tests have been fixed to pass on platforms with a stack alignment
larger than 4.

Update to clang side tests will land shortly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196939 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-10 18:27:32 +00:00
Reid Kleckner
cc8d39acf5 Revert "Fix miscompile of MS inline assembly with stack realignment"
This reverts commit r196876.  Its tests failed on the bots, so I'll
figure it out tomorrow.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196879 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-10 05:31:27 +00:00
Reid Kleckner
ec4d326aad Fix miscompile of MS inline assembly with stack realignment
For stack frames requiring realignment, three pointers may be needed:
- ebp to address incoming arguments
- esi (could be any callee-saved register) to address locals
- esp to address outgoing arguments

We would use esi unconditionally without verifying that it did not
conflict with inline assembly.

This change doesn't do the verification, it simply emits a fatal error
on functions that use stack realignment, dynamic SP adjustments, and
inline assembly.

Because stack realignment is common on Windows, we also no longer assume
that MS inline assembly clobbers esp.  Instead, we analyze the inline
instructions for implicit definitions and check if esp is there.  If so,
we require the use of a base pointer and consider it in the condition
above.

Mostly fixes PR16830, but we could try harder to find a non-conflicting
base pointer.

Reviewers: sunfish

Differential Revision: http://llvm-reviews.chandlerc.com/D1317

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196876 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-10 05:12:23 +00:00
Andrew Trick
e15c1079cb Fix a crash that occurs when PWD is invalid.
MCJIT needs to be able to run in hostile environments, even when PWD
is invalid. There's no need to crash MCJIT in this case.

The obvious fix is to simply leave MCContext's CompilationDir empty
when PWD can't be determined. This way, MCJIT clients,
and other clients that link with LLVM don’t need a valid working directory.

If we do want to guarantee valid CompilationDir, that should be done
only for clients of getCompilationDir(). This is as simple as checking
for an empty string.

The only current use of getCompilationDir is EmitGenDwarfInfo, which
won’t conceivably run with an invalid working dir. However, in the
purely hypothetically and untestable case that this happens, the
AT_comp_dir will be omitted from the compilation_unit DIE.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196874 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-10 04:39:09 +00:00
Andrew Trick
7a70a1bdaa whitespace
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196873 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-10 04:39:05 +00:00
Rafael Espindola
470041bd61 Use a more direct check for finding out the file type.
No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196811 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-09 20:26:40 +00:00
David Peixotto
7db4f8d9d8 Cache AllowAtInIdentifier as class variable in AsmLexer
This commit caches the value of the AllowAtInIdentifier variable as
a class variable in AsmLexer. We do this to avoid repeated MAI
queries and string comparisons each time we lex an identifier.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196622 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-06 23:05:33 +00:00
David Peixotto
d05b93515d Integrated assembler incorrectly lexes ARM-style comments
The integrated assembler fails to properly lex arm comments when
they are adjacent to an identifier in the input stream. The reason
is that the arm comment symbol '@' is also used as symbol variant in
other assembly languages so when lexing an identifier it allows the
'@' symbol as part of the identifier.

Example:
  $ cat comment.s
  foo:
    add r0, r0@got to parse this as a comment

  $ llvm-mc -triple armv7 comment.s
  comment.s:4:18: error: unexpected token in argument list
    add r0, r0@got to parse this as a comment
                   ^
This should be parsed as correctly as `add r0, r0`.

This commit modifes the assembly lexer to not include the '@' symbol
in identifiers when lexing for targets that use '@' for comments.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196607 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-06 20:35:58 +00:00
Alp Toker
087ab613f4 Correct word hyphenations
This patch tries to avoid unrelated changes other than fixing a few
hyphen-related ambiguities and contractions in nearby lines.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196471 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-05 05:44:44 +00:00
Logan Chien
175fe68393 [mc] Fix ELF st_other flag.
ELF_Other_Weakref and ELF_Other_ThumbFunc seems to be LLVM
internal ELF symbol flags.  These should not be emitted to
object file.

This commit defines ELF_STO_Shift for the target-defined
flags for st_other, and increase the value of
ELF_Other_Shift to 16.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196440 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-05 00:34:11 +00:00
David Peixotto
0fc8c68b11 Add support for parsing ARM symbol variants on ELF targets
ARM symbol variants are written with parens instead of @ like this:

  .word __GLOBAL_I_a(target1)

This commit adds support for parsing these symbol variants in
expressions. We introduce a new flag to MCAsmInfo that indicates the
parser should use parens to parse the symbol variant. The expression
parser is modified to look for symbol variants using parens instead
of @ when the corresponding MCAsmInfo flag is true.

The MCAsmInfo parens flag is enabled only for ARM on ELF.

By adding this flag to MCAsmInfo, we are able to get rid of
redundant ARM-specific symbol variants and use the generic variants
instead (e.g. VK_GOT instead of VK_ARM_GOT). We use the new
UseParensForSymbolVariant attribute in MCAsmInfo to correctly print
the symbol variants for arm.

To achive this we need to keep a handle to the MCAsmInfo in the
MCSymbolRefExpr class that we can check when printing the symbol
variant.

Updated Tests:
  Changed case of symbol variant to match the generic kind.
  test/CodeGen/ARM/tls-models.ll
  test/CodeGen/ARM/tls1.ll
  test/CodeGen/ARM/tls2.ll
  test/CodeGen/Thumb2/tls1.ll
  test/CodeGen/Thumb2/tls2.ll

PR18080


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196424 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-04 22:43:20 +00:00
Rafael Espindola
045d547516 Fix a funny typo.
Thanks for j`ey and Sean Silva for noticing it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196344 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-04 02:26:54 +00:00
Rafael Espindola
d060bfc11e Produce deterministic coff files.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196341 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-04 02:02:55 +00:00
David Blaikie
445cfd70b9 Avoid buffer copies when a Twine already is a StringRef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196301 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-03 18:18:28 +00:00
Rafael Espindola
9472fd7403 Refactor the setting of PrivateGlobalPrefix.
No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196170 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-02 23:39:26 +00:00