Commit Graph

175 Commits

Author SHA1 Message Date
Jim Ingham 6ca76ceb63 Fix a thinko in handling the QSetLogging packet.
The comparison against LOG_MEMORY shortcut all the LOG_MEMORY_*
log channels.  It has to come last.

llvm-svn: 371560
2019-09-10 21:58:22 +00:00
Jason Molenda fe64323fd5 Send error message on failed attach from debugerserver.
Instead of using a magic return error code from debugserver to
indicate that an attach failed because of SIP being enabled in
RNBRemote::HandlePacket_v, use the extended error reporting that
Pavel added to lldb/lldb-server in https://reviews.llvm.org/D45573


<rdar://problem/39398385> 

llvm-svn: 369990
2019-08-27 00:08:27 +00:00
Jason Molenda 6cebeafac3 Upstream a few small Apple changes to debugserver - arm64_32, Catalyst
Adrian's changes to support Catalyst processes and my
changes to support debugserver running on an arm64_32
device (Apple Watch Series 4, which uses an IPL32 model
on arm64 cpus).

llvm-svn: 368118
2019-08-07 02:06:06 +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
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
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
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
Jonas Devlieghere 8d20cfdfc6 [NFC] Replace `compare` with (in)equality operator where applicable.
Using compare is verbose, bug prone and potentially inefficient (because
of early termination). Replace relevant call sites with the (in)equality
operator.

llvm-svn: 349972
2018-12-21 22:46:10 +00:00
Jason Molenda 681f6c2f55 Un-conditionalize use of libcompression. debugserver only builds
on Darwin systems and libcompression has been in the OS for over
three years. 

Remove use of / linking to zlib.  We'll always have libcompression
available now.

Create a scratch buffer via compression_encode_scratch_buffer_size()
and use it in calls to compression_encode_buffer() to avoid 
compression_encode_buffer having to malloc & free a scratch buffer
on each call.  

Tested by forcing compression to be enabled on macos native (normally
only enabled on iOS et al devices), running the testsuite.

<rdar://problem/41601084>

llvm-svn: 349553
2018-12-18 22:21:48 +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
Jonas Devlieghere 672d2c1255 Remove comments after header includes.
This patch removes the comments following the header includes. They were
added after running IWYU over the LLDB codebase. However they add little
value, are often outdates and burdensome to maintain.

Differential revision: https://reviews.llvm.org/D54385

llvm-svn: 346625
2018-11-11 23:16:43 +00:00
Jason Molenda a1050973ed Remove llvm include from debugserver, change
LLVM_FALLTHROUGH's to [[clang::fallthrough]] -
debugserver is only ever compiled on darwin
systems with clang.

llvm-svn: 346553
2018-11-09 20:31:41 +00:00
Adrian Prantl 567906d8c7 Add missing include
llvm-svn: 346527
2018-11-09 17:58:05 +00:00
Adrian Prantl 96d37cf537 Annotate switch with LLVM_FALLTHROUGH
llvm-svn: 346519
2018-11-09 17:11:17 +00:00
Alex Langford 9391061fd7 Delete some dead code
llvm-svn: 334320
2018-06-08 21:13:26 +00:00
Adrian Prantl 6e9f77126b Silence compiler warning.
llvm-svn: 331375
2018-05-02 17:11:43 +00:00
Davide Italiano e185dcf13d Revert "[debugserver] Remove dead function call. NFCI."
This reverts commit r330066 as it was wrong and the call was
not dead. Thanks to Fred for pointing this out.

llvm-svn: 330071
2018-04-13 21:26:32 +00:00
Davide Italiano 0bd55b187e [debugserver] Remove dead function call. NFCI.
llvm-svn: 330066
2018-04-13 20:47:25 +00:00
Frederic Riss cd90f878d4 [debugserver] Fix LC_BUILD_VERSION load command handling.
Summary:
In one of the 2 places the LC_BUILD_VERSION load command is handled, there
is a bug preventing us from actually handling them (the address where to
read the load command was not updated). This patch factors reading the
deployment target load commands into a helper and adds testing for the 2
code paths calling the helper.

The testing is a little bit complicated because the only times those load
commands matter is when debugging a simulator process. I added a new
decorator to check that a specific SDK is available. The actual testing was
fairly easy once I knew how to run a simulated process.

Reviewers: jasonmolenda, labath

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D45298

llvm-svn: 329374
2018-04-06 04:28:12 +00:00
Jason Molenda a1bd9508e0 Upstreaming avx512 register support in debugserver. These changes
were originally written by Chris Bieneman, they've undergone a
number of changes since then.

Also including the debugserver bridgeos support, another arm
environment that runs Darwin akin to ios.  These codepaths are
activated when running in a bridgeos environment which we're not
set up to test today.

There's additional (small) lldb changes to handle bridgeos binaries
that still need to be merged up.

Tested on a darwin system with avx512 hardware and without.

<rdar://problem/36424951> 

llvm-svn: 326756
2018-03-06 00:27:41 +00:00
Jason Molenda c4dd04c5c3 When parsing the target.xml register file, if no architecture has
been specified yet (either by the user, or by one of the lldb
extensions like qHostInfo or qProcessInfo), and the target.xml
includes a <architecture> tag specifying x86_64, set the architecture
appropriately.

I'm not sure what we can expect to see in the <architecture> tag, so
I'm only doing this for x86_64 right now where I've seen "i386:x86_64"
used.  I've seen a target.xml from a jtag board that sends just "arm"
because it doesn't know more specifically what type of board it is
connected to...  

<rdar://problem/29908970> 

llvm-svn: 322339
2018-01-12 01:16:13 +00:00
Jason Molenda aae5b69079 Change uses of strncpy in debugserver to strlcpy
for better safety.

<rdar://problem/32906923> 

llvm-svn: 320242
2017-12-09 03:37:09 +00:00
Vedant Kumar 07d956149b Fix misc -Wcast-qual warnings, NFC
llvm-svn: 319937
2017-12-06 19:21:11 +00:00
Vedant Kumar 606908aab5 Remove no-op function pointer null checks, NFC
Null-checking functions which aren't marked weak_import is a no-op
(the compiler rewrites the check to 'true'), regardless of whether a
library providing its definition is weak-linked. If the deployment
target is greater than the minimum requirement, the availability markup
on APIs does not lower to weak_import.

Remove no-op null checks to clean up the code and silence warnings.

Differential Revision: https://reviews.llvm.org/D40812

llvm-svn: 319936
2017-12-06 19:21:10 +00:00
Jason Molenda d2d4c8db45 Update default cpu subtype for armv7 processes to armv7k, the most
likely cpu subtype at this point.

llvm-svn: 306752
2017-06-29 22:50:53 +00:00
Zachary Turner 97206d5727 Rename Error -> Status.
This renames the LLDB error class to Status, as discussed
on the lldb-dev mailing list.

A change of this magnitude cannot easily be done without
find and replace, but that has potential to catch unwanted
occurrences of common strings such as "Error".  Every effort
was made to find all the obvious things such as the word "Error"
appearing in a string, etc, but it's possible there are still
some lingering occurences left around.  Hopefully nothing too
serious.

llvm-svn: 302872
2017-05-12 04:51:55 +00:00
Jason Molenda 11506a9d1c Correct the names of some target conditional defines in debugserver.
llvm-svn: 301034
2017-04-21 20:19:28 +00:00
Jason Molenda 3ca38564cb Fix the last commit; compression was being enabled on mac native
which led to

ERROR: test_auxv_chunked_reads_work_debugserver (tools/lldb-server/TestGdbRemoteAuxvSupport.py)
ERROR: test_auxv_data_is_correct_size_debugserver (tools/lldb-server/TestGdbRemoteAuxvSupport.py)
ERROR: test_auxv_keys_look_valid_debugserver (tools/lldb-server/TestGdbRemoteAuxvSupport.py)
ERROR: test_qSupported_returns_known_stub_features_debugserver (tools/lldb-server/TestLldbGdbServer.py)

failures because debugserver was advertising compression being available, e.g.

send packet: $qSupported:xmlRegisters=i386,arm,mips#12
read packet: $qXfer:features:read+;PacketSize=20000;qEcho+;SupportedCompressions=zlib-deflate;DefaultCompressionMinSize=384#00

maybe these tests should be a little more accepting of additional
features.  but I didn't mean for this to be enabled on mac native.

llvm-svn: 292890
2017-01-24 06:09:06 +00:00
Jason Molenda 5a6826ebc4 Enable compression capability in debugserver for all of ios/watchos/tvos
environments.

<rdar://problem/30159019> 

llvm-svn: 292882
2017-01-24 04:43:40 +00:00
Pavel Labath 72090c2162 Move StdStringExtractor to tools/debugserver
The class is only used in the debugserver. The rest of lldb has the StringExtractor class.

Xcode project will need to be updated after this.

llvm-svn: 281226
2016-09-12 16:13:05 +00:00
Kate Stone b9c1b51e45 *** This commit represents a complete reformatting of the LLDB source code
*** to conform to clang-format’s LLVM style.  This kind of mass change has
*** two obvious implications:

Firstly, merging this particular commit into a downstream fork may be a huge
effort.  Alternatively, it may be worth merging all changes up to this commit,
performing the same reformatting operation locally, and then discarding the
merge for this particular commit.  The commands used to accomplish this
reformatting were as follows (with current working directory as the root of
the repository):

    find . \( -iname "*.c" -or -iname "*.cpp" -or -iname "*.h" -or -iname "*.mm" \) -exec clang-format -i {} +
    find . -iname "*.py" -exec autopep8 --in-place --aggressive --aggressive {} + ;

The version of clang-format used was 3.9.0, and autopep8 was 1.2.4.

Secondly, “blame” style tools will generally point to this commit instead of
a meaningful prior commit.  There are alternatives available that will attempt
to look through this change and find the appropriate prior commit.  YMMV.

llvm-svn: 280751
2016-09-06 20:57:50 +00:00
Zachary Turner 44c35e80b1 Copy StringExtractor to StdStringExtractor.
I have some improvements to make to StringExtractor that require
using LLVM.  debugserver can't take a dependency on LLVM but uses
this file, so I'm forking it off into StdStringExtractor and
StringExtractor, so that StringExtractor can take advantage of
some performance improvements and readability improvements that
LLVM can provide.

llvm-svn: 279997
2016-08-29 19:45:59 +00:00
Todd Fiala 759300192a Add StructuredData plugin type; showcase with new DarwinLog feature
Take 2, with missing cmake line fixed.  Build tested on
Ubuntu 14.04 with clang-3.6.

See docs/structured_data/StructuredDataPlugins.md for details.

differential review: https://reviews.llvm.org/D22976

reviewers: clayborg, jingham
llvm-svn: 279202
2016-08-19 04:21:48 +00:00
Todd Fiala a07e4a8352 Revert "Add StructuredData plugin type; showcase with new DarwinLog feature"
This reverts commit 1d885845d1451e7b232f53fba2e36be67aadabd8.

llvm-svn: 279200
2016-08-19 03:03:58 +00:00
Todd Fiala aef7de8492 Add StructuredData plugin type; showcase with new DarwinLog feature
See docs/structured_data/StructuredDataPlugins.md for details.

differential review: https://reviews.llvm.org/D22976

reviewers: clayborg, jingham
llvm-svn: 279198
2016-08-19 02:52:07 +00:00
Todd Fiala abd6186216 Undo usage of LLVM macros in debugserver
We don't take a dependency on LLVM in debugserver.
This was failing to compile before.

llvm-svn: 278190
2016-08-10 00:53:21 +00:00
Zachary Turner f343968f5d Delete Host/windows/win32.h
It's always hard to remember when to include this file, and
when you do include it it's hard to remember what preprocessor
check it needs to be behind, and then you further have to remember
whether it's windows.h or win32.h which you need to include.

This patch changes the name to PosixApi.h, which is more appropriately
named, and makes it independent of any preprocessor setting.

There's still the issue of people not knowing when to include this,
because there's not a well-defined set of things it exposes other
than "whatever is missing on Windows", but at least this should
make it less painful to fix when problems arise.

This patch depends on LLVM revision r278170.

llvm-svn: 278177
2016-08-09 23:06:08 +00:00
Jason Molenda a2992311a2 Add support to debugserver for some new ways to interact with dyld
to find the solibs loaded in a process.  Support two new ways of
sending the jGetLoadedDynamicLibrariesInfos packet to debugserver
and add a new jGetSharedCacheInfo packet.  Update the documentation
for these packets as well.  The changes to lldb to use these will
be a separate commit.

<rdar://problem/25251243> 

llvm-svn: 274718
2016-07-07 01:09:23 +00:00
Saleem Abdulrasool d97dd11f2f debugserver; fix -Wunused-local-typedef, -Wunused-variable warnings
Remove the typedef and local structure which was unused.  Fixes last of the new
clang warnings in the debugserver build.  NFC.

llvm-svn: 268759
2016-05-06 17:33:13 +00:00
Saleem Abdulrasool 247731d4d3 debugserver: fix a couple of -Wmissing-field-initializers warnings
Explicitly provide an initializer for the std::vector in the constructed type.
Addresses -Wmissing-field-initializers warnings from clang.  NFC.

llvm-svn: 268758
2016-05-06 17:33:09 +00:00
Saleem Abdulrasool 4533f7b6e8 debugserver: fix some -Wpessimizing-move warnings
Remove the unnecessary use of std::move to permit the compiler to perform NVRO
instead.  Fixes more warnings from clang.  NFC.

llvm-svn: 268757
2016-05-06 17:33:04 +00:00
Saleem Abdulrasool 2bb818880b debugserver: fix a few -Wcovered-swift-default warnings
Remove a couple of `default` cases from switches which are covered.  This is
beneficial since it would allow the compiler to indicate when a new enum value
is added and the switch is not updated.  Fixes some warnings from clang.  NFC.

llvm-svn: 268756
2016-05-06 17:33:01 +00:00
Greg Clayton 830c81d511 Fixed an issue that could cause debugserver to return two stop reply packets ($T packets) for one \x03 interrupt. The problem was that when a \x03 byte is sent to debugserver while the process is running, and up calling:
rnb_err_t
RNBRemote::HandlePacket_stop_process (const char *p)
{
    if (!DNBProcessInterrupt(m_ctx.ProcessID()))
        HandlePacket_last_signal (NULL);
    return rnb_success;
}

In the call to DNBProcessInterrupt we did:

nub_bool_t
DNBProcessInterrupt(nub_process_t pid)
{
    MachProcessSP procSP;
    if (GetProcessSP (pid, procSP))
        return procSP->Interrupt();
    return false;
}

This would always return false. It would cause HandlePacket_stop_process to always call "HandlePacket_last_signal (NULL);" which would send an extra stop reply packet _if_ the process is stopped. On a machine with enough cores, it would call DNBProcessInterrupt(...) and then HandlePacket_last_signal(NULL) so quickly that it will never send out an extra stop reply packet. But if the machine is slow enough or doesn't have enough cores, it could cause the call to HandlePacket_last_signal() to actually succeed and send an extra stop reply packet. This would cause problems up in GDBRemoteCommunicationClient::SendContinuePacketAndWaitForResponse() where it would get the first stop reply packet and then possibly return or execute an async packet. If it returned, then the next packet that was sent will get the second stop reply as its response. If it executes an async packet, the async packet will get the wrong response.

To fix this I did the following:
1 - in debugserver, I fixed "bool MachProcess::Interrupt()" to return true if it sends the signal so we avoid sending the stop reply twice on slower machines
2 - Added a log line to RNBRemote::HandlePacket_stop_process() to say if we ever send an extra stop reply so we will see this in the darwin console output if this does happen
3 - Added response validators to StringExtractorGDBRemote so that we can verify some responses to some packets. 
4 - Added validators to packets that often follow stop reply packets like the "m" packet for memory reads, JSON packets since "jThreadsInfo" is often sent immediately following a stop reply.
5 - Modified GDBRemoteCommunicationClient::SendPacketAndWaitForResponseNoLock() to validate responses. Any "StringExtractorGDBRemote &response" that contains a valid response verifier will verify the response and keep looking for correct responses up to 3 times. This will help us get back on track if we do get extra stop replies. If a StringExtractorGDBRemote does not have a response validator, it will accept any packet in response.
6 - In GDBRemoteCommunicationClient::SendPacketAndWaitForResponse we copy the response validator from the "response" argument over into m_async_response so that if we send the packet by interrupting the running process, we can validate the response we actually get in GDBRemoteCommunicationClient::SendContinuePacketAndWaitForResponse()
7 - Modified GDBRemoteCommunicationClient::SendContinuePacketAndWaitForResponse() to always check for an extra stop reply packet for 100ms when the process is interrupted. We were already doing this because we might interrupt a process with a \x03 packet, yet the process was in the process of stopping due to another reason. This race condition could cause an extra stop reply packet because the GDB remote protocol says if a \x03 packet is sent while the process is stopped, we should send a stop reply packet back. Now we always check for an extra stop reply packet when we manually interrupt a process.

The issue was showing up when our IDE would attempt to set a breakpoint while the process is running and this would happen:

--> \x03
<-- $T<stop reply 1>
--> z0,AAAAA,BB (set breakpoint)
<-- $T<stop reply 1> (incorrect extra stop reply packet)
--> c
<-- OK (response from z0 packet)

Now all packet traffic was off by one response. Since we now have a validator on the response for "z" packets, we do this:

--> \x03
<-- $T<stop reply 1>
--> z0,AAAAA,BB (set breakpoint)
<-- $T<stop reply 1> (Ignore this because this can't be the response to z0 packets)
<-- OK -- (we are back on track as this is a valid response to z0)
...

As time goes on we should add more packet validators.

<rdar://problem/22859505>

llvm-svn: 265086
2016-04-01 00:41:29 +00:00
Greg Clayton 17499dde46 A while back in revison 244716 we added support for getting the host OS version info from debugserver. We added keys to "qHostInfo" that were "osmajor", "osminor" and "ospatch", but no one ever parsed those, so I am removing them from debugserver. We accidentally also added a "version" key to qHostInfo instead of "os_version". So now we need to support both "version" and "os_version" in qHostInfo since we have debugserver binaries out in the wild that support this old packet type. I have updated debugserver ot use the correct "os_version" for future compatability or correctness.
<rdar://problem/24378699> 

llvm-svn: 259003
2016-01-28 00:16:11 +00:00
Sean Callanan 10badfc924 Fixed some #ifdefs. We were erroneously not supporting certain simulators.
We had some #ifdefs that were looking for the wrong #defines and as a result
debugserver didn't have support for certain simulators.  This patch resolves
the problem.

llvm-svn: 258365
2016-01-20 23:12:39 +00:00
Jason Molenda 77f8935218 Changes to lldb and debugserver to reduce extraneous memory reads
at each public stop to improve performance a bit.  Most of the 
information lldb needed was already in the jThreadsInfo response;
complete that information and catch a few cases where we could still
fall back to getting the information via discrete memory reads.


debugserver adds 'associated_with_dispatch_queue' and 'dispatch_queue_t
keys to the jThreadsInfo response for all the threads.  lldb needs the
dispatch_queue_t value.  And associated_with_dispatch_queue helps to
identify which threads definitively don't have any queue information so
lldb doesn't try to do memory reads to get that information just because
it was absent in the jThreadsInfo response.

Remove the queue information from the questionmark (T) packet.  We'll
get the information for all threads via the jThreadsInfo response -
sending the information for the stopping thread (on all the private
stops, plus the less frequent public stop) was unnecessary information
being sent over the wire.

SystemRuntimeMacOSX will try to get information about queues by asking
the Threads for them, instead of reading memory.  

ProcessGDBRemote changes to recognize the new keys being sent in the
jThreadsInfo response.  Changes to ThreadGDBRemote to track the new
information.  Also, when a thread is marked as definitively not 
associated with a libdispatch queue, don't fall back to the system
runtime to try memory reads to find the queue name / kind / ID etc.


<rdar://problem/23309359> 

llvm-svn: 257453
2016-01-12 07:09:16 +00:00
Jason Molenda 0c015c6279 In the questionmark packet ("T"), print the "threads:" and "thread-pcs:"
keys before we print the libdispatch queues keys (qname, qkind, qserialnum)
to make it easier to read the packet by hand.  No function difference, just
reordering the keys in the output.

llvm-svn: 257229
2016-01-08 23:16:03 +00:00
Jason Molenda 26d84e8097 Change the key name for the libdispatch queue serial number from
"qserial" to "qserialnum" because "qserial" looks a lot like the
queue type (either 'serial' or 'concurrent') and can be confusing
to read through.  debugserver passes these up either in the questionmark
("T") packet, or in the response to the jThreadsInfo packet.

llvm-svn: 257121
2016-01-08 00:20:48 +00:00
Jason Molenda 7e9bd599a2 Add a new "thread-pcs" key-value pair to the T packet response from
debugserver.  thread-pcs has a comma separated list of base 16
addresses - the current pc value for every thread in the process.
It is a partner of the "threads:" key where a list of thread IDs
is given.  The pc values in thread-pcs correspond one-to-one with
the thread IDs in the threads list.

This is a part of performance work.  When lldb is instruction
stepping / fast stepping over a range of addresses for e.g. a "next"
command, and it steps in to another function, lldb will put a
breakpoint on the return address and continue the process.  Before
it calls continue, it calls Thread::SetupForResume on all the
threads, and SetupForResume needs to get the current pc value for
every thread to see if any are at a breakpoint site.

The result is that issuing a "c" continue requires that we send
"read pc register" packets for every thread.

We may do this sequence of step-into-function / continue-to-get-out
many times for a single user-visible "next" or "step" command, and
with highly multithreaded programs, we are sending many extra
packets to get all the thread values.

I looked at including this data in the "jstopinfo" JSON that
we already have in the T packet.  But there are three problems that
would make this increase the size of the T packet significantly.
First, numbers in JSON are base 10.  Second, a proper JSON would
have something like "thread_pcs": { "34224331112":383772734222, ...}
for thread-id 34224331112 and pc 383772734222 - so we're including
a whole extra copy of the thread id in addition to the pc.  Third,
the JSON text is hex-ascii'fied so the size of it is doubled.
In one example, 

threads:585db8,585dc7,585dc8,585dc9,585dca,585dce;thread-pcs:100001400,7fff8badc6de,7fff8badcff6,7fff8badc6de,7fff8badc6de,7fff8badc6de;

The "thread-pcs" adds 86 characters - 136 characters for both 
threads and thread-pcs.  Doing this in JSON would look like

threads={"5791160":4294972416,"5791175":140735536809694,"5791176":140735536812022,"5791177":140735536809694,"5791178":140735536809694,"5791182":140735536809694}

or 160 characters -- or 320 characters once it is hex-asciified.

Given that it's 86 characters vrs 320, I went with the old style
approach.  I've seen real world programs that have up to 60 threads
in them, so this could result in vastly larger packets if it
was all done in the JSON with hex-ascii expansion.

If we had an all-JSON T packet, where we didn't need to hex-ascii
encode anything, that would have been the better approach.  But
we'd already have a list of threads in JSON at that point so
the additional text wouldn't be too bad.

I'm working on finishing the patches to lldb to use this data;
will commit those once I've had a chance to test them more.  But
I wanted to commit the debugserver bits which are more
straightforward.


<rdar://problem/21963031> 

llvm-svn: 255711
2015-12-15 23:47:44 +00:00
Jason Molenda 0071be6590 When supplying memory to expedite the unwinds in the T packet,
include two stack frames worth of unwind information instead of
just one -- the unwinder is trying to fetch two stack frames in
more instances now and we're sending extra memory reads resulting
in a performance degredation while stepping.

llvm-svn: 255417
2015-12-12 01:32:09 +00:00