Commit Graph

316 Commits

Author SHA1 Message Date
Raphael Isemann 42fb94993d [lldb][NFC] Rename ReadRegisterValue to PrintRegisterValue
That was the actual name I had in mind, but it seems git didn't pick
that change up when committing my previous commit.

llvm-svn: 370856
2019-09-04 09:18:10 +00:00
Raphael Isemann ac6aff70a8 [lldb][NFC] Remove WriteRegister copy-pasta from ObjectFileMachO
The function had the same name as one of the member function, so
it was just copied to all classes so that the lookup works. We
could also give the function a more better and unique name
(because it's actually printing the register value and writing
to the stream, not writing to the register).

Also removes the unused return value.

llvm-svn: 370854
2019-09-04 09:10:28 +00:00
Adrian Prantl f869ec8d49 Upstream support for macCatalyst Mach-O binaries.
On macOS one Mach-O slice can contain multiple load commands: One load
command for being loaded into a macOS process and one load command for
being loaded into a macCatalyst process. This patch adds support for
the new load command and makes sure ObjectFileMachO returns the
Architecture that matches the Module.

Differential Revision: https://reviews.llvm.org/D66626

llvm-svn: 369814
2019-08-23 21:28:14 +00:00
Jonas Devlieghere a8f3ae7c9c [LLDB] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

Differential revision: https://reviews.llvm.org/D66259

llvm-svn: 368933
2019-08-14 22:19:23 +00:00
Pavel Labath e84f78412b Add llvm-style RTTI to ObjectFile hierarchy
Summary:
On the heels of D62934, this patch uses the same approach to introduce
llvm RTTI support to the ObjectFile hierarchy. It also replaces the
existing uses of GetPluginName doing run-time type checks with
llvm::dyn_cast and friends.

This formally introduces new dependencies from some other plugins to
ObjectFile plugins. However, I believe this is fine because:
- these dependencies were already kind of there, and the only reason
  we could get away with not modeling them explicitly was because the
  code was relying on magically knowing what will GetPluginName() return
  for a particular kind of object files.
- the dependencies themselves are logical (it makes sense for
  SymbolVendorELF to depend on ObjectFileELF), or at least don't
  actively get in the way (the JitLoaderGDB->MachO thing).
- they don't introduce any new dependency loops as ObjectFile plugins
  don't depend on any other plugins

Reviewers: xiaobai, JDevlieghere, espindola

Subscribers: emaste, mgorny, arichardson, MaskRay, lldb-commits

Differential Revision: https://reviews.llvm.org/D65450

llvm-svn: 367413
2019-07-31 11:57:34 +00:00
Jonas Devlieghere 63e5fb76ec [Logging] Replace Log::Printf with LLDB_LOG macro (NFC)
This patch replaces explicit calls to log::Printf with the new LLDB_LOGF
macro. The macro is similar to LLDB_LOG but supports printf-style format
strings, instead of formatv-style format strings.

So instead of writing:

  if (log)
    log->Printf("%s\n", str);

You'd write:

  LLDB_LOG(log, "%s\n", str);

This change was done mechanically with the command below. I replaced the
spurious if-checks with vim, since I know how to do multi-line
replacements with it.

  find . -type f -name '*.cpp' -exec \
  sed -i '' -E 's/log->Printf\(/LLDB_LOGF\(log, /g' "{}" +

Differential revision: https://reviews.llvm.org/D65128

llvm-svn: 366936
2019-07-24 17:56:10 +00:00
Jason Molenda 956761adb0 Fall back to dyld's _dyld_start when no LC_MAIN / main() func can be found
The new DriverKit user-land kernel drivers in macOS 10.15 / Catalina 
do not have a main() function or an LC_MAIN load command.  lldb uses
the address of main() as the return address for inferior function
calls; it puts a breakpoint on main, runs the inferior function call,
and when the main() breakpoint is hit, lldb knows unambiguously that
the inferior function call ran to completion - no other function calls
main.

This change hoists the logic for finding the "entry address" from 
ThreadPlanCallFunction to Target.  It changes the logic to first
try to get the entry address from the main executable module,
but if that module does not have one, it will iterate through all
modules looking for an entry address.

The patch also adds code to ObjectFileMachO to use dyld's 
_dyld_start function as an entry address.

<rdar://problem/52343958> 

Differential Revision: https://reviews.llvm.org/D64897

llvm-svn: 366493
2019-07-18 20:55:24 +00:00
Raphael Isemann e0afcd8d26 Refactor ObjectFile::GetSDKVersion
Summary: This patch modernizes the GetSDKVersion API and hopefully prevents problems such as the ones discovered in D61218.

Reviewers: aprantl, jasonmolenda, clayborg

Reviewed By: aprantl, clayborg

Subscribers: clayborg, labath, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D61233

llvm-svn: 365090
2019-07-03 22:21:10 +00:00
Jim Ingham f2128b28cd Get the expression parser to handle missing weak symbols.
MachO only for this patch.

Differential Revision: https://reviews.llvm.org/D63914

<rdar://problem/51463642>

llvm-svn: 364686
2019-06-28 21:40:05 +00:00
Pavel Labath ad805ef95a Recognise debug_types.dwo as a debug info section
This is a preparatory patch to allow reading type units from dwo files.

llvm-svn: 363146
2019-06-12 11:42:42 +00:00
Jonas Devlieghere 09ad8c8f73 Fix integer literals which are cast to bool
This change replaces built-in types that are implicitly converted to
booleans.

Differential revision: https://reviews.llvm.org/D62284

llvm-svn: 361580
2019-05-24 00:44:33 +00:00
Konrad Kleine 248a13057a [lldb] NFC modernize codebase with modernize-use-nullptr
Summary:
NFC = [[ https://llvm.org/docs/Lexicon.html#nfc | Non functional change ]]

This commit is the result of modernizing the LLDB codebase by using
`nullptr` instread of `0` or `NULL`. See
https://clang.llvm.org/extra/clang-tidy/checks/modernize-use-nullptr.html
for more information.

This is the command I ran and I to fix and format the code base:

```
run-clang-tidy.py \
	-header-filter='.*' \
	-checks='-*,modernize-use-nullptr' \
	-fix ~/dev/llvm-project/lldb/.* \
	-format \
	-style LLVM \
	-p ~/llvm-builds/debug-ninja-gcc
```

NOTE: There were also changes to `llvm/utils/unittest` but I did not
include them because I felt that maybe this library shall be updated in
isolation somehow.

NOTE: I know this is a rather large commit but it is a nobrainer in most
parts.

Reviewers: martong, espindola, shafik, #lldb, JDevlieghere

Reviewed By: JDevlieghere

Subscribers: arsenm, jvesely, nhaehnle, hiraditya, JDevlieghere, teemperor, rnkovacs, emaste, kubamracek, nemanjai, ki.stfu, javed.absar, arichardson, kbarton, jrtc27, MaskRay, atanasyan, dexonsmith, arphaman, jfb, jsji, jdoerfert, lldb-commits, llvm-commits

Tags: #lldb, #llvm

Differential Revision: https://reviews.llvm.org/D61847

llvm-svn: 361484
2019-05-23 11:14:47 +00:00
Jonas Devlieghere 8b3af63b89 [NFC] Remove ASCII lines from comments
A lot of comments in LLDB are surrounded by an ASCII line to delimit the
begging and end of the comment.

Its use is not really consistent across the code base, sometimes the
lines are longer, sometimes they are shorter and sometimes they are
omitted. Furthermore, it looks kind of weird with the 80 column limit,
where the comment actually extends past the line, but not by much.
Furthermore, when /// is used for Doxygen comments, it looks
particularly odd. And when // is used, it incorrectly gives the
impression that it's actually a Doxygen comment.

I assume these lines were added to improve distinguishing between
comments and code. However, given that todays editors and IDEs do a
great job at highlighting comments, I think it's worth to drop this for
the sake of consistency. The alternative is fixing all the
inconsistencies, which would create a lot more churn.

Differential revision: https://reviews.llvm.org/D60508

llvm-svn: 358135
2019-04-10 20:48:55 +00:00
Davide Italiano 454e9428db [ObjectFileMachO] Remove another debugging aid.
Pointed out by Jason.

llvm-svn: 357135
2019-03-28 00:07:20 +00:00
Davide Italiano dfbcadf562 [ObjectFileMachO] Disable memory caching for savecore.
Summary:
It's not really useful, and largely increases the footprint.

<rdar://problem/49293525>

Reviewers: jasonmolenda

Subscribers: llvm-commits, lldb-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59896

llvm-svn: 357134
2019-03-28 00:07:07 +00:00
Adrian Prantl 0e4c482124 Pass ConstString by value (NFC)
My apologies for the large patch. With the exception of ConstString.h
itself it was entirely produced by sed.

ConstString has exactly one const char * data member, so passing a
ConstString by reference is not any more efficient than copying it by
value. In both cases a single pointer is passed. But passing it by
value makes it harder to accidentally return the address of a local
object.

(This fixes rdar://problem/48640859 for the Apple folks)

Differential Revision: https://reviews.llvm.org/D59030

llvm-svn: 355553
2019-03-06 21:22:25 +00:00
Pavel Labath b8093314ef Move RangeMap.h into Utility
Summary:
This file implements some general purpose data structures, and so it
belongs to the Utility module.

Reviewers: zturner, jingham, JDevlieghere, clayborg, espindola

Subscribers: emaste, mgorny, javed.absar, arichardson, MaskRay, lldb-commits

Differential Revision: https://reviews.llvm.org/D58970

llvm-svn: 355509
2019-03-06 14:41:43 +00:00
Jonas Devlieghere d5b440369d Replace 'ap' with 'up' suffix in variable names. (NFC)
The `ap` suffix is a remnant of lldb's former use of auto pointers,
before they got deprecated. Although all their uses were replaced by
unique pointers, some variables still carried the suffix.

In r353795 I removed another auto_ptr remnant, namely redundant calls to
::get for unique_pointers. Jim justly noted that this is a good
opportunity to clean up the variable names as well.

I went over all the changes to ensure my find-and-replace didn't have
any undesired side-effects. I hope I didn't miss any, but if you end up
at this commit doing a git blame on a weirdly named variable, please
know that the change was unintentional.

llvm-svn: 353912
2019-02-13 06:25:41 +00:00
Jonas Devlieghere 70355ace3f Remove redundant ::get() for smart pointer. (NFC)
This commit removes redundant calls to smart pointer’s ::get() method.

https://clang.llvm.org/extra/clang-tidy/checks/readability-redundant-smartptr-get.html

llvm-svn: 353795
2019-02-12 03:47:39 +00:00
Jonas Devlieghere 9d0c5f9953 Define _ENABLE_EXTENDED_ALIGNED_STORAGE on Windows.
Apparently there are multiple places where MSVC complains about
instantiations with extended aligment. I think it's better to define
`_ENABLE_EXTENDED_ALIGNED_STORAGE` as suggested by the error message.

I don't have access to a Windows machine so this is all speculative.

llvm-svn: 353778
2019-02-12 00:30:21 +00:00
Jonas Devlieghere 55fb848e84 [ObjectFileMachO] Revert std::make_shared
This caused a rather interesting error message on MSVC: error C2338 and
I'm not sure how to properly fix it.

llvm-svn: 353769
2019-02-11 23:49:13 +00:00
Jonas Devlieghere 796ac80b86 Use std::make_shared in LLDB (NFC)
Unlike std::make_unique, which is only available since C++14,
std::make_shared is available since C++11. Not only is std::make_shared
a lot more readable compared to ::reset(new), it also performs a single
heap allocation for the object and control block.

Differential revision: https://reviews.llvm.org/D57990

llvm-svn: 353764
2019-02-11 23:13:08 +00:00
Pavel Labath bd334efd0a Simplify ObjectFile::GetUUID
instead of returning the UUID through by-ref argument and a boolean
value indicating success, we can just return it directly. Since the UUID
class already has an invalid state, it can be used to denote the failure
without the additional bool.

llvm-svn: 353714
2019-02-11 16:14:02 +00:00
Jan Kratochvil bb3609e49d Fix strlen() of unbound array undefined behavior
LLDB testsuite fails when built by GCC8 on:
  LLDB :: SymbolFile/DWARF/find-basic-namespace.cpp

This is because this code in LLDB codebase has undefined behavior:

  #include <algorithm>
  #include <string.h>
  // lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp:1731
  static struct section_64 {
    char sectname[16];
    char segname[16];
  } sect64 = { {'_','_','a','p','p','l','e','_','n','a','m','e','s','p','a','c'}, "__DWARF" };
  int main() {
    return std::min<size_t>(strlen(sect64.sectname), sizeof(sect64.sectname));
  }

It has been discussed as a (false) bugreport to GCC:
  wrong-code: LLDB testcase fails: SymbolFile/DWARF/find-basic-namespace.cpp
  https://bugzilla.redhat.com/show_bug.cgi?id=1672436

Differential Revision: https://reviews.llvm.org/D57781

llvm-svn: 353280
2019-02-06 08:44:13 +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
Pavel Labath f760f5aef4 Simplify ObjectFile::GetArchitecture
Summary:
instead of returning the architecture through by-ref argument and a
boolean value indicating success, we can just return the ArchSpec
directly. Since the ArchSpec already has an invalid state, it can be
used to denote the failure without the additional bool.

Reviewers: clayborg, zturner, espindola

Subscribers: emaste, arichardson, JDevlieghere, lldb-commits

Differential Revision: https://reviews.llvm.org/D56129

llvm-svn: 350291
2019-01-03 10:37:19 +00:00
Greg Clayton 57577c0634 Don't duplicate the logic that detects if a section can/should be loaded (NFC)
Prior to this there were 3 places that were duplicating the logic to detect if a section can/should be loaded and some were doing things a bit differently. Now it is all centralized in one place and it is done correctly.

llvm-svn: 349926
2018-12-21 17:04:18 +00:00
Jonas Devlieghere a6682a413d Simplify Boolean expressions
This patch simplifies boolean expressions acorss LLDB. It was generated
using clang-tidy with the following command:

run-clang-tidy.py -checks='-*,readability-simplify-boolean-expr' -format -fix $PWD

Differential revision: https://reviews.llvm.org/D55584

llvm-svn: 349215
2018-12-15 00:15:33 +00:00
Pavel Labath d1e3fe2190 Rename ObjectFile::GetHeaderAddress to GetBaseAddress
Summary:
This function was named such because in the case of MachO files, the
mach header is located at this address. However all (most?) usages of
this function were not interested in that fact, but the fact that this
address is used as the base address for expressing various relative
addresses in the object file.

For other object file formats, this name is not appropriate (and it's
probably the reason why this function was not implemented in these
classes). In the ELF case the ELF header will usually end up at this
address, but this is a result of the linker optimizing the file layout
and not a requirement of the spec. For COFF files, I believe the is no
header located at this address either.

Reviewers: clayborg, jasonmolenda, amccarth, lemo, stella.stamenova

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D55422

llvm-svn: 348849
2018-12-11 15:21:15 +00:00
George Rimar 004bcb78ed [LLDB] - Recommit r346848 "[LLDB] - Support the single file split DWARF.".
Test cases were updated to not use the local compilation dir which
is different between development pc and build bots.

Original commit message:

[LLDB] - Support the single file split DWARF.

DWARF5 spec describes a single file split dwarf case
(when .dwo sections are in the .o files).

Problem is that LLDB does not work correctly in that case.
The issue is that, for example, both .debug_info and .debug_info.dwo
has the same type: eSectionTypeDWARFDebugInfo. And when code searches
section by type it might find the regular debug section
and not the .dwo one.

The patch fixes that. With it, LLDB is able to work with
output compiled with -gsplit-dwarf=single flag correctly.

Differential revision: https://reviews.llvm.org/D52403

llvm-svn: 346855
2018-11-14 13:01:15 +00:00
George Rimar 7cdb22b1ef Revert r346848 "[LLDB] - Support the single file split DWARF."
It broke BB:
http://green.lab.llvm.org/green/job/lldb-cmake/12522/testReport/junit/LLDB/Breakpoint/single_file_split_dwarf_test/

llvm-svn: 346853
2018-11-14 12:04:31 +00:00
George Rimar 98963db57d [LLDB] - Support the single file split DWARF.
DWARF5 spec describes a single file split dwarf case
(when .dwo sections are in the .o files).

Problem is that LLDB does not work correctly in that case.
The issue is that, for example, both .debug_info and .debug_info.dwo
has the same type: eSectionTypeDWARFDebugInfo. And when code searches
section by type it might find the regular debug section
and not the .dwo one.

The patch fixes that. With it, LLDB is able to work with
output compiled with -gsplit-dwarf=single flag correctly.

Differential revision: https://reviews.llvm.org/D52296

llvm-svn: 346848
2018-11-14 10:35:14 +00:00
Adrian Prantl 874e32dcf2 Fix a bug in the parsing of the LC_BUILD_VERSION Mach-O load command.
LC_BUILD_VERSION records are of variable length. The original code
would use uninitialized memory when the size of a record was exactly 24.

rdar://problem/46032185

llvm-svn: 346812
2018-11-13 23:14:37 +00:00
Jonas Devlieghere ceff6644bb Remove header grouping comments.
This patch removes the comments grouping header includes. They were
added after running IWYU over the LLDB codebase. However they add little
value, are often outdates and burdensome to maintain.

llvm-svn: 346626
2018-11-11 23:17:06 +00:00
Jonas Devlieghere 50bc1ed290 [FileSystem] Open File instances through the FileSystem.
This patch modifies how we open File instances in LLDB. Rather than
passing a path or FileSpec to the constructor, we now go through the
virtual file system. This is needed in order to make things work with
the VFS in the future.

Differential revision: https://reviews.llvm.org/D54020

llvm-svn: 346049
2018-11-02 22:34:51 +00:00
Davide Italiano 407c6910d4 Revert "[Symbol] Search symbols with name and type in a symbol file"
It broke MacOS buildbots.

llvm-svn: 346045
2018-11-02 21:59:14 +00:00
Aleksandr Urakov 15da7684db [Symbol] Search symbols with name and type in a symbol file
Summary:
This patch adds possibility of searching a public symbol with name and type in a
symbol file. It is helpful when working with PE, because PE's symtabs contain
only imported / exported symbols only. Such a search is required for e.g.
evaluation of an expression that calls some function of the debuggee.

Reviewers: zturner, asmith, labath, clayborg, espindola

Reviewed By: clayborg

Subscribers: emaste, arichardson, aleksandr.urakov, jingham, lldb-commits, stella.stamenova

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D53368

llvm-svn: 345957
2018-11-02 08:54:35 +00:00
Jonas Devlieghere 8f3be7a32b [FileSystem] Move path resolution logic out of FileSpec
This patch removes the logic for resolving paths out of FileSpec and
updates call sites to rely on the FileSystem class instead.

Differential revision: https://reviews.llvm.org/D53915

llvm-svn: 345890
2018-11-01 21:05:36 +00:00
Jonas Devlieghere dbd7fabaa0 [FileSystem] Remove Exists() from FileSpec
This patch removes the Exists method from FileSpec and updates its uses
with calls to the FileSystem.

Differential revision: https://reviews.llvm.org/D53845

llvm-svn: 345854
2018-11-01 17:09:25 +00:00
George Rimar e4dee2696e [LLDB] - Implement the support for the .debug_loclists section.
This implements the support for .debug_loclists section, which is
DWARF 5 version of .debug_loc.

Currently, clang is able to emit it with the use of D53365.

Differential revision: https://reviews.llvm.org/D53436

llvm-svn: 345016
2018-10-23 09:46:15 +00:00
Jason Molenda dcb3c28fd8 Don't mark an LC_BUILD_VERSION as giving us a
correct version if it has a major verison 0.

llvm-svn: 344275
2018-10-11 18:37:53 +00:00
Eric Liu 7d2f783e7d [lldb] rename MinOS::minor to MinOS::minor_version etc. NFC
The constructor initializer minor(...)/major(...) can be confused with system
macros `#define minor(...)` on some platforms.

llvm-svn: 344250
2018-10-11 14:44:12 +00:00
Jason Molenda 32762fd29d Upstreaming the BridgeOS device support and the
LC_BUILD_VERSION load command handling - this
commit is a combination of patches by Adrian
Prantl and myself.  llvm::Triple::BridgeOS 
isn't defined yet, so all references to that
are currently commented out.  

Also update Xcode project file to build the 
NativePDB etc plugins.

<rdar://problem/43353615> 

llvm-svn: 344209
2018-10-11 00:28:35 +00:00
George Rimar 6e357123ed [LLDB] - Add basic support for .debug_rnglists section (DWARF5)
This adds a basic support of the .debug_rnglists section.
Only the DW_RLE_start_length and DW_RLE_end_of_list entries are supported.

Differential revision: https://reviews.llvm.org/D52981

llvm-svn: 344119
2018-10-10 08:11:15 +00:00
George Rimar c6c7bfc4d2 [LLDB] - Improved DWARF5 support.
This patch improves the support of DWARF5.
Particularly the reporting of source code locations.

Differential revision: https://reviews.llvm.org/D51935

llvm-svn: 342153
2018-09-13 17:06:47 +00:00
Pavel Labath 7704473172 Move SafeMachO from Utility to Host
Summary:
One of the conclusions of the discussion on D49740 was that SafeMachO is better
off in the Host module (as that's the only place which should include
mach/machine.h, which is what this header is working around). Also, Utility,
which is the only module which cannot include Host, should not be doing
anything with object file formats.

This patch implements that move, and also removes any unneded includes of that
file.

I've verified that MacOS still compiles after this.

Reviewers: jingham, zturner, teemperor

Subscribers: fedor.sergeev, lldb-commits

Differential Revision: https://reviews.llvm.org/D50383

llvm-svn: 342050
2018-09-12 12:26:05 +00:00
Jason Molenda b0d33e9b3c Re-instate a bit of code that was commented out in r188246 which
reads an ObjectFileMachO's string table in one chunk.  Originally
this was commented out because binaries in the system's shared cache
all share a mega-string table and so reading the entire mega-strtab
for each binary was a performance problem.

In the reinstated code, I add a check that the binary we're reading
from memory is not in the shared cache (there isn't a constant in
<mach-o/loader.h> for this bit yet; we hardcode the value in one
other place in ObjectFileMachO alread).  For binaries that we're
reading out of memory that are NOT in the shared cache, reading 
the string table in one chunk is a big performance improvement.

Also have debugserver send up the flags value for binaries in its
response to the jGetLoadedDynamicLibrariesInfos request.

NFC.

<rdar://problem/33604496> 

llvm-svn: 341511
2018-09-06 00:55:27 +00:00
Jim Ingham 8a5d7a2784 Fix a little thinko in generating ___lldb_unnamed_symbol symbols
when we have only an in-memory copy of the binary.

Also added a test for the generation of these symbols in the 
in-memory and regular cases.

<rdar://problem/43160401>

llvm-svn: 339833
2018-08-15 23:10:32 +00:00
Pavel Labath d821c997aa Move RegisterValue,Scalar,State from Core to Utility
These three classes have no external dependencies, but they are used
from various low-level APIs. Moving them down to Utility improves
overall code layering (although it still does not break any particular
dependency completely).

The XCode project will need to be updated after this change.

Differential Revision: https://reviews.llvm.org/D49740

llvm-svn: 339127
2018-08-07 11:07:21 +00:00
Pavel Labath 2f93fd1f50 Represent invalid UUIDs as UUIDs with length zero
Summary:
During the previous attempt to generalize the UUID class, it was
suggested that we represent invalid UUIDs as length zero (previously, we
used an all-zero UUID for that). This meant that some valid build-ids
could not be represented (it's possible however unlikely that a checksum of
some file would be zero) and complicated adding support for variable
length build-ids (should a 16-byte empty UUID compare equal to a 20-byte
empty UUID?).

This patch resolves these issues by introducing a canonical
representation for an invalid UUID. The slight complication here is that
some clients (MachO) actually use the all-zero notation to mean "no UUID
has been set". To keep this use case working (while making it very
explicit about which construction semantices are wanted), replaced the
UUID constructors and the SetBytes functions with named factory methods.
- "fromData" creates a UUID from the given data, and it treats all bytes
  equally.
- "fromOptionalData" first checks the data contents - if all bytes are
  zero, it treats this as an invalid/empty UUID.

Reviewers: clayborg, sas, lemo, davide, espindola

Subscribers: emaste, lldb-commits, arichardson

Differential Revision: https://reviews.llvm.org/D48479

llvm-svn: 335612
2018-06-26 15:12:20 +00:00