Commit Graph

1516 Commits

Author SHA1 Message Date
Michał Górny 8567f4d4b9 [lldb] Support querying registers via generic names without alt_names
Update GetRegisterInfoByName() methods to support getting registers
by a generic name independently of alt_name entries in the register
context.  This makes it possible to use generic names when interacting
with gdbserver (that does not supply alt_names).  It also makes it
possible to remove some of the duplicated information from register
context declarations and/or use alt_names for another purpose.

Differential Revision: https://reviews.llvm.org/D108554
2021-09-13 13:05:06 +02:00
Raphael Isemann 4b2e38d940 [lldb][NFC] Cleanup EditlineHistory 2021-09-13 09:30:31 +02:00
Raphael Isemann 4f7fb13f87 [lldb] Don't save empty expressions in the multiline editor history
Right now running `expr` to start the multiline expression editor and then
pressing enter causes an empty history empty to be created for the multiline
editor. That doesn't seem very useful for users as pressing the 'up' key will
now also bring up these empty expressions.

I don't think there is ever a use case for recalling a completely empty
expression from the history, so instead don't save those entries to the history
file and make sure we never recall them when navigating over the expression
history.

Note: This is actually a Swift downstream patch that got shipped with Apple's
LLDB for many years. However, this recently started conflicting with upstream
LLDB as D100048 added a test that made sure that empty expression entries don't
crash LLDB. Apple's LLDB was never affected by this crash as it never saved
empty expressions in the first place.

Reviewed By: augusto2112

Differential Revision: https://reviews.llvm.org/D108983
2021-08-31 18:51:18 +02:00
Hiroki ffcf571107 [LLDB] Fix 'std::out_of_range' crashing bug when file name completion using file path.
When I run a lldb command that uses filename completion, if I enter a string
that is not only a filename but also a string with a non-file name string added,
such as "./" that is relative path string , it will crash as soon as I press the
[Tab] key. For example, debugging an executable file named "hello" that is
compiled from a file named "hello.c" , and I’ll put a breakpoint on line 3 of
hello.c.

```
$ lldb ./hello
(lldb) breakpoint set --file hello.c --line 3
```

This is not a problem, but if I set "--file ./hello."  and then press [Tab] key
to complete file name, lldb crashes.

```
$ lldb ./hello
(lldb) breakpoint set --file ./hello.terminate called after throwing an instance of 'std::out_of_range'
  what():  basic_string::substr: __pos (which is 8) > this->size() (which is 7)
```

The crash was caused because substr() (in lldb/source/Host/common/Editline.cpp)
cut out string which size is user's input string from the completion string.

I modified the code that erase the user's intput string from current line and
then add the completion string.

Differential Revision: https://reviews.llvm.org/D108817
2021-08-30 15:14:09 +02:00
Rumeet Dhindsa d9c5613e85 Update logic to close inherited file descriptors.
This patch adds the support to close all inherited fds into the child
process by iterating over /proc/self/fd entries.

Differential Revision: https://reviews.llvm.org/D105732
2021-08-19 14:40:43 -07:00
Michał Górny 8bbef4f9af [lldb] [gdb-remote] Sync vFile:open mode constants with GDB
Sync the mode constants used to drive vFile:open requests with these
used by GDB and defined for the gdb remote protocol.  This makes it
possible to use 'platform file open' after connecting to gdbremote
server (and to some degree to operate on the open file modulo other
incompatibilities).

Differential Revision: https://reviews.llvm.org/D106985
2021-08-09 12:07:18 +02:00
Michał Górny 14735cab65 [lldb] [gdb-remote] Add eOpenOptionReadWrite for future gdb compat
Modify OpenOptions enum to open the future path into synchronizing
vFile:open bits with GDB.  Currently, LLDB and GDB use different flag
models effectively making it impossible to match bits.  Notably, LLDB
uses two bits to indicate read and write status, and uses union of both
for read/write.  GDB uses a value of 0 for read-only, 1 for write-only
and 2 for read/write.

In order to future-proof the code for the GDB variant:

1. Add a distinct eOpenOptionReadWrite constant to be used instead
   of (eOpenOptionRead | eOpenOptionWrite) when R/W access is required.

2. Rename eOpenOptionRead and eOpenOptionWrite to eOpenOptionReadOnly
   and eOpenOptionWriteOnly respectively, to make it clear that they
   do not mean to be combined and require update to all call sites.

3. Use the intersection of all three flags when matching against
   the three possible values.

This commit does not change the actual bits used by LLDB.

Differential Revision: https://reviews.llvm.org/D106984
2021-08-09 12:06:59 +02:00
Neal Sidhwaney 55fd6f292f Revert "D106035: Remove conditional compilation for WCHAR support in libedit"
This reverts commit 7529f0e3e1.
2021-08-05 02:55:10 -07:00
Neal Sidhwaney 7529f0e3e1 D106035: Remove conditional compilation for WCHAR support in libedit
This change moves to using narrow character types and libedit APIs in
Editline, because those are the same types that the rest of LLVM/LLDB
uses, and it's generally considered better practice to use UTF-8
encoded in char than it is to use wider characters. However, for
character input, the change leaves in using a wchar to enable input of
multi-byte characters.

Differential Revision: https://reviews.llvm.org/D106035
2021-08-05 00:29:54 -07:00
Fangrui Song 72a83674dd Replace LLVM_ATTRIBUTE_NORETURN with C++11 [[noreturn]]. NFC
[[noreturn]] can be used since Oct 2016 when the minimum compiler requirement was bumped to GCC 4.8/MSVC 2015.
2021-07-29 09:59:45 -07:00
David Spickett 7d27230de3 [lldb][AArch64] Add memory tag writing to lldb-server
This is implemented using the QMemTags packet, as specified
by GDB in:
https://sourceware.org/gdb/current/onlinedocs/gdb/General-Query-Packets.html#General-Query-Packets

(recall that qMemTags was previously added to read tags)

On receipt of a valid packet lldb-server will:
* align the given address and length to granules
  (most of the time lldb will have already done this
  but the specification doesn't guarantee it)
* Repeat the supplied tags as many times as needed to cover
  the range. (if tags > range we just use as many as needed)
* Call ptrace POKEMTETAGS to write the tags.

The ptrace step will loop just like the tag read does,
until all tags are written or we get an error.
Meaning that if ptrace succeeds it could be a partial write.
So we call it again and if we then get an error, return an error to
lldb.

We are not going to attempt to restore tags after a partial
write followed by an error. This matches the behaviour of the
existing memory writes.

The lldb-server tests have been extended to include read and
write in the same test file. With some updated function names
since "qMemTags" vs "QMemTags" isn't very clear when they're
next to each other.

Reviewed By: omjavaid

Differential Revision: https://reviews.llvm.org/D105180
2021-07-27 12:02:17 +01:00
Jonas Devlieghere fd2433e139 [lldb] Replace default bodies of special member functions with = default;
Replace default bodies of special member functions with = default;

$ run-clang-tidy.py -header-filter='lldb' -checks='-*,modernize-use-equals-default' -fix ,

https://clang.llvm.org/extra/clang-tidy/checks/modernize-use-equals-default.html

Differential revision: https://reviews.llvm.org/D104041
2021-07-02 11:31:16 -07:00
Raphael Isemann 355541a1b7 [lldb] Avoid using any shell when calling xcrun.
When we run `xcrun` we don't have any user input in our command so relying on
the user's default shell doesn't make a lot of sense. If the user has set the
system shell to a something that isn't supported yet (dash, ash) then we would
run into the problem that we don't know how to escape our command string.

This patch just avoids using any shell at all as xcrun is always at the same
path.

Reviewed By: aprantl, JDevlieghere, kastiglione

Differential Revision: https://reviews.llvm.org/D104653
2021-06-28 19:53:52 +02:00
Martin Storsjö e50f9c419a [lldb] Rename StringRef _lower() method calls to _insensitive() 2021-06-25 00:22:01 +03:00
David Spickett da2e614f56 [lldb][AArch64] Add memory tag reading to lldb-server
This adds memory tag reading using the new "qMemTags"
packet and ptrace on AArch64 Linux.

This new packet is following the one used by GDB.
(https://sourceware.org/gdb/current/onlinedocs/gdb/General-Query-Packets.html)

On AArch64 Linux we use ptrace's PEEKMTETAGS to read
tags and we assume that lldb has already checked that the
memory region actually has tagging enabled.

We do not assume that lldb has expanded the requested range
to granules and expand it again to be sure.
(although lldb will be sending aligned ranges because it happens
to need them client side anyway)
Also we don't assume untagged addresses. So for AArch64 we'll
remove the top byte before using them. (the top byte includes
MTE and other non address data)

To do the ptrace read NativeProcessLinux will ask the native
register context for a memory tag manager based on the
type in the packet. This also gives you the ptrace numbers you need.
(it's called a register context but it also has non register data,
so it saves adding another per platform sub class)

The only supported platform for this is AArch64 Linux and the only
supported tag type is MTE allocation tags. Anything else will
error.

Ptrace can return a partial result but for lldb-server we will
be treating that as an error. To succeed we need to get all the tags
we expect.

(Note that the protocol leaves room for logical tags to be
read via qMemTags but this is not going to be implemented for lldb
at this time.)

Reviewed By: omjavaid

Differential Revision: https://reviews.llvm.org/D95601
2021-06-24 17:02:55 +01:00
Raphael Isemann 8a5165b3b9 [lldb][NFC] Remove some redundant semicolons on HostInfoMacOSX 2021-06-23 15:06:12 +02:00
Raphael Isemann 48e2d3a5c2 [lldb][NFC] Remove an outdated comment in HostInfoBase
We should *never* use static local variables in this file as this makes
unittesting the plugin code impossible (and this whole 'testing' thing has
turned out to be rather useful so far).
2021-06-22 16:48:17 +02:00
Vitaly Buka f3f904563e [lldb] Fix leak in test
Test leaks if we run
tools/lldb/unittests/Host/HostTests without --gtest_filter

Reviewed By: teemperor

Differential Revision: https://reviews.llvm.org/D104091
2021-06-11 00:20:35 -07:00
Raphael Isemann 632cbcac79 [lldb] Move once_flags in HostInfoLinux so the internal state struct
The HostInfoLinuxFields struct is supposed to be set up/torn down on
Initialize/Terminate and should contain all the state of the plugin.
`once_flags` are part of this state and should also be reset on `Terminate` so
we can re-initialize these lazy values after the next `Initialize` call.

This itself is NFC as the HostInfoLinux was broken before this patch and is
still broken afterwards. D104091 will be the proper fix.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D104093
2021-06-11 08:53:38 +02:00
Jonas Devlieghere 9494c510af [lldb] Use C++11 default member initializers
This converts a default constructor's member initializers into C++11
default member initializers. This patch was automatically generated with
clang-tidy and the modernize-use-default-member-init check.

$ run-clang-tidy.py -header-filter='lldb' -checks='-*,modernize-use-default-member-init' -fix

This is a mass-refactoring patch and this commit will be added to
.git-blame-ignore-revs.

Differential revision: https://reviews.llvm.org/D103483
2021-06-09 09:43:13 -07:00
Raphael Isemann 76e47d4887 [lldb][NFC] Use C++ versions of the deprecated C standard library headers
The C headers are deprecated so as requested in D102845, this is replacing them
all with their (not deprecated) C++ equivalent.

Reviewed By: shafik

Differential Revision: https://reviews.llvm.org/D103084
2021-05-26 12:46:12 +02:00
Neal (nealsid) 5af3a6645f Remove Windows editline from LLDB
I don't mean to undo others' work but it looks like the hand-rolled EditLine for LLDB on Windows isn't used.  It'd be easier to make changes to bring the other platforms' Editline wrapper up to date (e.g. simplifying char vs wchar_t) without modifying/testing this one too.

Reviewed By: amccarth

Differential Revision: https://reviews.llvm.org/D102208
2021-05-12 10:05:44 +01:00
Neal (nealsid) fd89af6880 Wrap edit line configuration calls into helper functions
Currently we call el_set directly to configure the editor in the libedit
wrapper.  There are some cases in which this causes extra casting, but we pass
captureless lambdas as function pointers, which should work out of the box.
Since el_set takes varargs, if the cast is incorrect or if the cast is not
present, it causes a run time failure rather than compile error.  This change
makes it so a few different types of configuration is done inside a helper
function to provide type safety and eliminate that casting.  I didn't do all
edit line configuration because I'm not sure how important it was in other cases
and it might require something more general keep up with libedit's signature.
I'm open to suggestions, though.

Reviewed By: teemperor, JDevlieghere

Differential Revision: https://reviews.llvm.org/D101250
2021-04-30 12:32:29 +02:00
Michał Górny 08ce2ba518 [lldb] [MainLoop] Support multiple callbacks per signal
Support registering multiple callbacks for a single signal.  This is
necessary to support multiple co-existing native process instances, with
separate SIGCHLD handlers.

The system signal handler is registered on first request, additional
callback are added on subsequent requests.  The system signal handler
is removed when last callback is unregistered.

Differential Revision: https://reviews.llvm.org/D100418
2021-04-21 12:18:20 +02:00
Jonas Devlieghere 479b672ff9 [lldb] Pretend host architecture is arm64 on AS
The arm64e architecture is a preview. On Apple Silicon, pretend the host
architecture is arm64.
2021-04-13 18:57:23 -07:00
Michał Górny c8d18cba4e Reland "[lldb] [Process] Watch for fork/vfork notifications" for Linux
Big thanks to Pavel Labath for figuring out my mistake.

Differential Revision: https://reviews.llvm.org/D98822
2021-04-13 14:38:31 +02:00
Pavel Labath 121cff78a8 Revert "[lldb] [Process] Watch for fork/vfork notifications" and associated followups
This commit has caused the following tests to be flaky:
TestThreadSpecificBpPlusCondition.py
TestExitDuringExpression.py

The exact cause is not known yet, but since both tests deal with
threads, my guess is it has something to do with the tracking of
creation of new threads (which the commit touches upon).

This reverts the following commits:
d01bff8cbd,
ba62ebc48e,
e761b6b4c5,
a345419ee0.
2021-04-13 11:03:06 +02:00
Pavel Labath c9cf394f79 [lldb] Replace NativeProcess delegate list with a single delegate
In all this time, we've never used more than one delegate. The logic to
support multiple delegates is therefore untested, and becomes
particularly unwieldy once we need to support multiple processes.

Just remove it.
2021-04-13 09:49:38 +02:00
Michał Górny a345419ee0 [lldb] [Process] Watch for fork/vfork notifications
Watch for fork(2)/vfork(2) (also fork/vfork-style clone(2) on Linux)
notifications and explicitly detach the forked child process, and add
initial tests for these cases.  The code covers FreeBSD, Linux
and NetBSD process plugins.  There is no new user-visible functionality
provided -- this change lays foundations over subsequent work on fork
support.

Differential Revision: https://reviews.llvm.org/D98822
2021-04-08 18:49:50 +02:00
Jordan Rupprecht f49a4440d3 [lldb][Editline] Fix crash when navigating through empty command history.
An empty history entry can happen by entering the expression evaluator an immediately hitting enter:

```
$ lldb
(lldb) e
Enter expressions, then terminate with an empty line to evaluate:
  1:  <hit enter>
```

The next time the user enters the expression evaluator, if they hit the up arrow to load the previous expression, lldb crashes. This patch treats empty history sessions as a single expression of zero length, instead of an empty list of expressions.

Fixes http://llvm.org/PR49845.

Differential Revision: https://reviews.llvm.org/D100048
2021-04-07 10:48:47 -07:00
Abhina Sreeskantharajan c83cd8feef [NFC] Reordering parameters in getFile and getFileOrSTDIN
In future patches I will be setting the IsText parameter frequently so I will refactor the args to be in the following order. I have removed the FileSize parameter because it is never used.

```
  static ErrorOr<std::unique_ptr<MemoryBuffer>>
  getFile(const Twine &Filename, bool IsText = false,
          bool RequiresNullTerminator = true, bool IsVolatile = false);

  static ErrorOr<std::unique_ptr<MemoryBuffer>>
  getFileOrSTDIN(const Twine &Filename, bool IsText = false,
                 bool RequiresNullTerminator = true);

 static ErrorOr<std::unique_ptr<MB>>
 getFileAux(const Twine &Filename, uint64_t MapSize, uint64_t Offset,
            bool IsText, bool RequiresNullTerminator, bool IsVolatile);

  static ErrorOr<std::unique_ptr<WritableMemoryBuffer>>
  getFile(const Twine &Filename, bool IsVolatile = false);
```

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D99182
2021-03-25 09:47:49 -04:00
Med Ismail Bennani 3e0ad11543 [lldb/Commands] Add command options for ScriptedProcess to ProcessLaunch
This patch adds a new command options to the CommandObjectProcessLaunch
for scripted processes.

Among the options, the user need to specify the class name managing the
scripted process. The user can also use a key-value dictionary holding
arbitrary data that will be passed to the managing class.

This patch also adds getters and setters to `SBLaunchInfo` for the
class name managing the scripted process and the dictionary.

rdar://65508855

Differential Review: https://reviews.llvm.org/D95710

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-03-23 18:24:47 +01:00
Neal (nealsid) 5826aa48f0 Migrate to llvm::unique_function instead of static member functions for callbacks
A few cleanups suggested in another patch review's comments:

1. Use llvm:unique_function for storing & invoking callbacks from
   Editline to IOHandler
2. Change return type of one of the callback setters from bool to void,
   since it's return value was never used
3. Moved the callback setters inline & made them nonstatic, since that's
   more consistent with other setter definitions
4. Removed the baton parameter since we no longer need it anymore

Differential revision: https://reviews.llvm.org/D50299
2021-03-02 16:13:54 -08:00
Med Ismail Bennani 36254f1a0f
[lldb] Revert ScriptedProcess patches
This patch reverts the following commits:
- 5a9c34918b
- 46796762af
- 2cff3dec11
- 182f0d1a34
- d62a53aaf1

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-03-01 23:23:27 +00:00
Jonas Devlieghere 6dbea3efc5 [lldb] Add scoped timer to HostInfoMacOSX::GetXcodeSDKPath 2021-03-01 14:57:42 -08:00
Med Ismail Bennani d62a53aaf1 [lldb/Commands] Add command options for ScriptedProcess to ProcessLaunch
This patch adds a new command options to the CommandObjectProcessLaunch
for scripted processes.

Among the options, the user need to specify the class name managing the
scripted process. The user can also use a key-value dictionary holding
arbitrary data that will be passed to the managing class.

This patch also adds getters and setters to `SBLaunchInfo` for the
class name managing the scripted process and the dictionary.

rdar://65508855

Differential Review: https://reviews.llvm.org/D95710

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-03-01 21:13:31 +01:00
Pavel Labath 004a264f8c [lldb] Fix shared library directory computation on windows
Our code for locating the shared library directory works via dladdr (or
the windows equivalent) to locate the path of an address known to reside
in liblldb. This works great for C++ programs, but there's a catch.

When (lib)lldb is used from python (like in our test suite), this dladdr
call will return a path to the _lldb.so (or such) file in the python
directory. To compensate for this, we have code which attempts to
resolve this symlink, to ensure we get the canonical location. However,
here's the second catch.

On windows, this file is not a symlink (but a copy), so this logic
fails. Since most of our other paths are derived from the liblldb
location, all of these paths will be wrong, when running the test suite.
One effect of this was the failure to find lldb-server in D96202.

To fix this issue, I add some windows-specific code to locate the
liblldb directory. Since it cannot rely on symlinks, it works by
manually walking the directory tree -- essentially doing the opposite of
what we do when computing the python directory.

To avoid python leaking back into the host code, I implement this with
the help of a callback which can be passed to HostInfo::Initialize in
order to assist with the directory location. The callback lives inside
the python plugin.

I also strenghten the existing path test to ensure the returned path is
the right one.

Differential Revision: https://reviews.llvm.org/D96779
2021-02-18 15:37:52 +01:00
Pavel Labath 1db2888e70 [lldb] Remove some nanosleep preprocessor magic
It's obsolete, as we use (portable) std::this_thread::sleep_for now.
2021-02-16 21:07:57 +01:00
Jonas Devlieghere 732534ed64 [lldb] s/TARGET_OS_EMBEDDED/TARGET_OS_IPHONE/
TARGET_OS_EMBEDDED is deprecated, use TARGET_OS_IPHONE and/or
TARGET_OS_SIMULATOR instead.
2021-02-11 20:40:59 -08:00
Michał Górny bd03f6df51 [lldb] [Process/FreeBSDRemote] Introduce powerpc support
Introduce a minimal support for the 32-bit powerpc platform.  This
includes support for GPR and FPR registers.  I also needed to add
software breakpoint opcode for PPC32/PPC64 (big endian), and to fix
offsets in RegisterInfos_powerpc.h (used only by FreeBSD register
context to be globally unique rather than relative to each struct).

Differential Revision: https://reviews.llvm.org/D95947
2021-02-09 21:10:45 +01:00
Jonas Devlieghere 98e50a7d4c [lldb] Honor the CPU type & subtype when launching on macOS
Honor the CPU type (and subtype) when launching the inferior on macOS.

Part of this functionality was thought to be no longer needed and
removed in 85bd436961, however it's still
needed, for example to launch binaries under Rosetta 2 on Apple Silicon.

This patch will use posix_spawnattr_setarchpref_np if available and
fallback to posix_spawnattr_setbinpref_np if not.

Differential revision: https://reviews.llvm.org/D95922
2021-02-03 13:42:00 -08:00
Nathan Hawes ecb00a7762 [VFS] Add support to RedirectingFileSystem for mapping a virtual directory to one in the external FS.
Previously file entries in the -ivfsoverlay yaml could map to a file in the
external file system, but directories had to list their contents in the form of
other file entries or directories. Allowing directory entries to map to a
directory in the external file system makes it possible to present an external
directory's contents in a different location and (in combination with the
'fallthrough' option) overlay one directory's contents on top of another.

rdar://problem/72485443
Differential Revision: https://reviews.llvm.org/D94844
2021-02-02 14:56:17 +10:00
Nathan Hawes 719f778441 [VFS] Combine VFSFromYamlDirIterImpl and OverlayFSDirIterImpl into a single implementation (NFC)
As a fixme notes, both of these directory iterator implementations are
conceptually similar and duplicate the functionality of returning and uniquing
entries across two or more directories. This patch combines them into a single
class 'CombiningDirIterImpl'.

This also drops the 'Redirecting' prefix from RedirectingDirEntry and
RedirectingFileEntry to save horizontal space. There's no loss of clarity as
they already have to be prefixed with 'RedirectingFileSystem::' whenever
they're referenced anyway.

rdar://problem/72485443
Differential Revision: https://reviews.llvm.org/D94857
2021-01-30 11:10:10 +10:00
Jonas Devlieghere 3a50ed84f4 [lldb] FixFileSystem::GetExternalPath for VFS API change 2021-01-22 15:04:17 -08:00
Pavel Labath 13dea030b3 [lldb] Fix some bugs in the Pipe class and add tests
- s/createUniqueFile/createUniquePath -- we don't want to create the file,
  just the file name
- s/data()/str().c_str()/ -- paths given to system apis must be
  null-terminated
2021-01-10 21:59:16 +01:00
Muhammad Omair Javaid b69c09bf43 Support custom expedited register set in gdb-remote
This patch adds capability to introduce a custom expedited register set
in gdb remote. Currently we send register set 0 as expedited register set
but for the case of AArch64 SVE we intend to send additional information
about SVE registers size/offset configuration which can be calculated
from vg register. Therefore we will expedited Vg register in case of
AArch64 is in SVE mode to speedup register configuration calculations.

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D82853
2020-11-30 17:34:19 +05:00
Raphael Isemann b4b836563a [lldb][NFC] Move OptionDefinition from lldb-private-types.h to its own Utility header
Also moves the curious isprint8 function (which was used to check whether we have a
valid short option) into the struct and documents it.
2020-11-12 15:30:26 +01:00
Michał Górny bc125665c5 [lldb] [Host/freebsd] Set Arg0 for 'platform process list -v'
Same fix as in NetBSD (a6712889f5).

Differential Revision: https://reviews.llvm.org/D91026
2020-11-09 12:09:12 +01:00
Michał Górny 2384c4f971 Revert "[lldb] [Host/freebsd] Set Arg0 for 'platform process list -v'"
Accidentally referenced the wrong diff.

This reverts commit fce8e75889.
2020-11-09 12:09:12 +01:00
Michał Górny fce8e75889 [lldb] [Host/freebsd] Set Arg0 for 'platform process list -v'
Same fix as in NetBSD (a6712889f5).

Differential Revision: https://reviews.llvm.org/D91012
2020-11-09 11:35:11 +01:00