Commit Graph

1477 Commits

Author SHA1 Message Date
Pavel Labath e4fc4ef463 [LLGS] Limit jThreadsInfo to only the most important registers for now
Summary:
It seems that reading of register data is the biggest bottleneck in LLGS at the moment. Sending
four registers instead of the full GPR set increases the jThreadsInfo processing time about
6-fold. Until we figure out where is this time going, this commit limits the amount of data we
send to provide a more fluid debugging experience.

Reviewers: tberghammer, ovyalov

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D11264

llvm-svn: 242517
2015-07-17 10:27:42 +00:00
Pavel Labath 4a4bb12e0d Add jThreadsInfo support to lldb-server
Summary:
This commit adds initial support for the jThreadsInfo packet to lldb-server. The current
implementation does not expedite inferior memory.  I have also added a description of the new
packet to our protocol documentation (mostly taken from Greg's earlier commit message).

Reviewers: clayborg, ovyalov, tberghammer

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D11187

llvm-svn: 242402
2015-07-16 14:14:35 +00:00
Pavel Labath 5abe726911 Revert "[NativeProcessLinux] Integrate MainLoop"
This seems to be causing major slowdows on the android buildbot. Reverting while I investigate.

llvm-svn: 242391
2015-07-16 08:45:03 +00:00
Greg Clayton a5801ade5a Added the ability to get JSON thread stop info with thread ID and stop info only in the normal stop reply packets using the new "jthreads" key value pair.
This allows stepping operations that don't ever do a public stop to get all the info they need without having to send a jThreadsInfo packet since those tend to be large.

This patch will be followed by a patch that will detect when we do a public stop, and when that happens we will send a jThreadsInfo packet at that time to get all expedited registers and memory.

llvm-svn: 242352
2015-07-15 22:59:03 +00:00
Keno Fischer ac351b7943 [Makefiles] One more library rename to align with CMake
This one I accidentally missed last time because I confused it with
the lldbUtility library. After this, all makefile libraries should
have the same names as their CMake counterparts.

llvm-svn: 242344
2015-07-15 22:39:44 +00:00
Pavel Labath 827965c33c [NativeProcessLinux] Integrate MainLoop
Summary:
This commit integrates MainLoop into NativeProcessLinux. By registering a SIGCHLD handler with
the llgs main loop, we can get rid of the special monitor thread in NPL, which saves as a lot of
thread ping-pong when responding to client requests (e.g. qThreadInfo processing time has been
reduced by about 40%). It also makes the code simpler, IMHO.

Reviewers: ovyalov, clayborg, tberghammer, chaoren

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D11150

llvm-svn: 242305
2015-07-15 17:20:01 +00:00
Jim Ingham 4920a4ef56 Fix another little nit with detach and keep stopped, you have to check
both for packet success and that the response is OK.

llvm-svn: 242262
2015-07-15 00:59:25 +00:00
Jason Molenda 2a66738f5c Correct length of packet that GDBRemoteCommunicationClient::Detach
should send when detaching and leaving the remote process/system
halted.  Previously only the 'D' initial char was sent, which
resumed the process like a normal detach.

llvm-svn: 242256
2015-07-15 00:16:09 +00:00
Jason Molenda fea7765219 Add comment explaning sanity check on packet size in the packet decompression method.
llvm-svn: 242184
2015-07-14 19:19:07 +00:00
Jason Molenda 21c34ac419 Fix off-by-one error in the packet decompression routine
that would not pass through empty ("unsupported packet") replies
correctly.

llvm-svn: 242119
2015-07-14 04:51:05 +00:00
Chaoren Lin e515a5a672 Fix FreeBSD build.
llvm-svn: 242113
2015-07-14 03:18:23 +00:00
Chaoren Lin 98d0a4b39a Refactor Unix signals.
Summary:
- Consolidate Unix signals selection in UnixSignals.
- Make Unix signals available from platform.
- Add jSignalsInfo packet to retrieve Unix signals from remote platform.
- Get a copy of the platform signal for each remote process.
- Update SB API for signals.
- Update signal utility in test suite.

Reviewers: ovyalov, clayborg

Subscribers: chaoren, jingham, labath, emaste, tberghammer, lldb-commits

Differential Revision: http://reviews.llvm.org/D11094

llvm-svn: 242101
2015-07-14 01:09:28 +00:00
Pavel Labath 77dc9569c6 Introduce a MainLoop class and switch llgs to use it
Summary:
This is the first part of our effort to make llgs single threaded. Currently, llgs consists of
about three threads and the synchronisation between them is a major source of latency when
debugging linux and android applications.

In order to be able to go single threaded, we must have the ability to listen for events from
multiple sources (primarily, client commands coming over the network and debug events from the
inferior) and perform necessary actions. For this reason I introduce the concept of a MainLoop.
A main loop has the ability to register callback's which will be invoked upon receipt of certain
events. MainLoopPosix has the ability to listen for file descriptors and signals.

For the moment, I have merely made the GDBRemoteCommunicationServerLLGS class use MainLoop
instead of waiting on the network socket directly, but the other threads still remain. In the
followup patches I indend to migrate NativeProcessLinux to this class and remove the remaining
threads.

Reviewers: ovyalov, clayborg, amccarth, zturner, emaste

Subscribers: tberghammer, lldb-commits

Differential Revision: http://reviews.llvm.org/D11066

llvm-svn: 242018
2015-07-13 10:44:55 +00:00
Jason Molenda 20ee21bde6 Add a another packet to the gdb-remote protocol,
jGetLoadedDynamicLibrariesInfos.  This packet is similar to
qXfer:libraries:read except that lldb supplies the number of solibs
that should be reported about, and the start address for the list
of them.  At the initial process launch we'll read the full list
of solibs linked by the process -- at this point we could be using
qXfer:libraries:read -- but on subsequence solib-loaded notifications,
we'll be fetching a smaller number of solibs, often only one or two.

A typical Mac/iOS GUI app may have a couple hundred different 
solibs loaded  - doing all of the loads via memory reads takes 
a couple of megabytes of traffic between lldb and debugserver.
Having debugserver summarize the load addresses of all the solibs
and sending it in JSON requires a couple of hundred kilobytes
of traffic.  It's a significant performance improvement when 
communicating over a slower channel.

This patch leaves all of the logic for loading the libraries
in DynamicLoaderMacOSXDYLD -- it only call over ot ProcesGDBRemote
to get the JSON result.

If the jGetLoadedDynamicLibrariesInfos packet is not implemented,
the normal technique of using memory read packets to get all of
the details from the target will be used.

<rdar://problem/21007465>

llvm-svn: 241964
2015-07-10 23:15:22 +00:00
Chaoren Lin 1bd3c9abd8 Fix 32-bit Linux watchpoint failures.
Summary:
32-bit signed return value from ptrace got sign extended when being converted to
64-bit unsigned.

Also, replaced tabs with spaces in the source.

Reviewers: labath, clayborg

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D11047

llvm-svn: 241837
2015-07-09 18:35:16 +00:00
Pavel Labath d5b310f2a3 Avoid going through Platform when creating a NativeProcessProtocol instance
Summary:
This commit avoids the Platform instance when spawning or attaching to a process in lldb-server.
Instead, I have the server call a (static) method of NativeProcessProtocol directly. The reason
for this is that I believe that NativeProcessProtocol should be decoupled from the Platform
(after all, it always knows which platform it is running on, unlike the rest of lldb).
Additionally, the kind of platform actions a NativeProcessProtocol instance is likely to differ
greatly from the platform actions of the lldb client, so I think the separation makes sense.

After this, the only dependency NativeProcessLinux has on PlatformLinux is the ResolveExecutable
method, which needs additional refactoring.

This is a resubmit of r241672, after it was reverted due to build failueres on non-linux
platforms.

Reviewers: ovyalov, clayborg

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D10996

llvm-svn: 241796
2015-07-09 11:51:11 +00:00
Stephane Sezer 9a7cacb5f6 Implement qXfer:libraries:read.
Summary:
This is used on non-unix platforms, where qXfer:libraries-svr4:read
doesn't make sense. Windows uses that for instance.

Reviewers: clayborg

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D11036

llvm-svn: 241712
2015-07-08 19:14:03 +00:00
Stephane Sezer 38a1b7ea58 Move WindowsDYLD to the Plugins/DynamicLoader directory.
Summary:
This commit moves the Windows DyanamicLoader to the common DynamicLoader
directory. This is required to remote debug Windows targets.

This commit also initializes the Windows DYLD plugin in
SystemInitializerCommon (similarly to both POSIX and MacOSX DYLD
plugins) so that we can automatically instantiate this class when
connected to a windows process.

Test Plan: Build.

Reviewers: zturner

Subscribers: lldb-commits, abdulras

Differential Revision: http://reviews.llvm.org/D10882

llvm-svn: 241697
2015-07-08 18:07:13 +00:00
Sean Callanan c307c27035 Revert r241672, which breaks the OS X build by introducing a dependency on
platform-specific symbols that are not implemented on OS X.

The build error that caused this is

Undefined symbols for architecture x86_64:
  "lldb_private::NativeProcessProtocol::Attach(unsigned long long, lldb_private::NativeProcessProtocol::NativeDelegate&, std::__1::shared_ptr<lldb_private::NativeProcessProtocol>&)", referenced from:
      lldb_private::process_gdb_remote::GDBRemoteCommunicationServerLLGS::AttachToProcess(unsigned long long) in liblldb-core.a(GDBRemoteCommunicationServerLLGS.o)
  "lldb_private::NativeProcessProtocol::Launch(lldb_private::ProcessLaunchInfo&, lldb_private::NativeProcessProtocol::NativeDelegate&, std::__1::shared_ptr<lldb_private::NativeProcessProtocol>&)", referenced from:
      lldb_private::process_gdb_remote::GDBRemoteCommunicationServerLLGS::LaunchProcess() in liblldb-core.a(GDBRemoteCommunicationServerLLGS.o)
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

llvm-svn: 241688
2015-07-08 16:33:46 +00:00
Pavel Labath 235c8405eb Avoid going through Platform when creating a NativeProcessProtocol instance
Summary:
This commit avoids the Platform instance when spawning or attaching to a process in lldb-server.
Instead, I have the server call a (static) method of NativeProcessProtocol directly. The reason
for this is that I believe that NativeProcessProtocol should be decoupled from the Platform
(after all, it always knows which platform it is running on, unlike the rest of lldb).
Additionally, the kind of platform actions a NativeProcessProtocol instance is likely to differ
greatly from the platform actions of the lldb client, so I think the separation makes sense.

After this, the only dependency NativeProcessLinux has on PlatformLinux is the ResolveExecutable
method, which needs additional refactoring.

Reviewers: ovyalov, clayborg

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D10996

llvm-svn: 241672
2015-07-08 09:08:53 +00:00
Bruce Mitchener 4578815289 Move ProcessKDP's StringExtractor include.
This can be in the cpp file rather than the header file, so moving
it there.

Summary: Move ProcessKDP's StringExtractor include.

Reviewers: clayborg

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D11018

llvm-svn: 241649
2015-07-07 23:59:01 +00:00
Bruce Mitchener 28529f607c Fix StringExtractor.h issues.
Summary:
Fix StringExtractor.h issues.

* source/Plugins/Process/MacOSX-Kernel/ProcessKDP.cpp
  (#include "Utility/StringExtractor.h): Not needed, this is already
    included by ProcessKDP.h

* unittests/Utility/StringExtractorTest.cpp
  (#include "Utility/StringExtractor.h): Update include path to the
    new location.

Reviewers: labath, clayborg

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D10995

llvm-svn: 241596
2015-07-07 15:19:03 +00:00
Pavel Labath 066fc8b194 Fix-up ProcessKDP wrt. StringExtractor move
llvm-svn: 241574
2015-07-07 11:00:55 +00:00
Pavel Labath f805e1905c Fix cmake build after recent JSON changes
I have moved StringExtractor.h into the include/ folder so that it can be properly included by
everyone.

llvm-svn: 241572
2015-07-07 10:08:41 +00:00
Adrian McCarthy 5cbef0e79f Fix step over breakpoint on Windows (which was detected by TestCreateAfterAttach.py).
llvm-svn: 241475
2015-07-06 17:42:09 +00:00
Tamas Berghammer 8d53464472 Improve UnwindLLDB with better detection for unwinding failures
Previously we accepted a frame as correct result if the PC pointed
into an executable section of code. The isse with that approac is
that if we calculated PC correctly but messed up the value of CFA
then unwinding from the next fram will most likely fail.

With this change I modify the logic with keeping the requirement
for PC to point to an executable section and also check that we can
continue the unwind from the frame we calculated. If continuing from
the frame calculated with the primary unwind plan isn't working then
fall back to the fallback plan with the hope for a better frame (if
the fallback plan won't help then we acceot the frame from the
primary plan).

Differential revision: http://reviews.llvm.org/D10932

llvm-svn: 241434
2015-07-06 09:24:20 +00:00
Tamas Berghammer ff7fd90017 Fix aarch64 breakpoint PC offset
llvm-svn: 241347
2015-07-03 12:51:30 +00:00
Tamas Berghammer cec93c355a Fix 128bit register read and user register count on aarch64
llvm-svn: 241340
2015-07-03 11:17:07 +00:00
Tamas Berghammer 9383480524 Enable usage of eh_frame based unwind plan as a fallback
Previously if the instruction emulation based unwind plan failed then
we fall back to the arch default unwind plan. Change it to fall back
to the eh_frame based one even on non call sites if we have eh_frame
as that one tend to be more reliable.

Differential revision: http://reviews.llvm.org/D10902

llvm-svn: 241334
2015-07-03 09:30:22 +00:00
Tamas Berghammer 09839c33b6 Fix qMemoryRegionInfo packet to return current value for address after the last memory region
Differential revision: http://reviews.llvm.org/D10899

llvm-svn: 241333
2015-07-03 09:30:19 +00:00
Bruce Mitchener a868c13c51 Fix typos
Summary: Fixes more typos.

Reviewers: clayborg

Subscribers: lldb-commits-list

Differential Revision: http://reviews.llvm.org/D10898

llvm-svn: 241289
2015-07-02 18:48:40 +00:00
Pavel Labath 4a9babb26e [NativeProcessLinux] Refactor PtraceWrapper
Summary:
This changes PtraceWrapper to return an Error, while the actual result is in an pointer parameter
(instead of the other way around). Also made a couple of PtraceWrapper arguments default to zero.
This arrangement makes a lot of the code much simpler.

Test Plan: Tests pass on linux. It compiles on android arm64/mips64.

Reviewers: chaoren, mohit.bhakkad

Subscribers: tberghammer, aemerson, lldb-commits

Differential Revision: http://reviews.llvm.org/D10808

llvm-svn: 241079
2015-06-30 17:04:49 +00:00
Ewan Crawford 0c996a9a06 Change search order of target definition files.
Make the python target definition file have highest priority so that we can set 
the remote stub breakpoint pc offset using it.

Reviewers: clayborg
Subscribers: ted, deepak2427, lldb-commits 

Differential revision: http://reviews.llvm.org/D10775

llvm-svn: 241063
2015-06-30 13:08:44 +00:00
Mohit K. Bhakkad e0d8c422a0 [LLDB][MIPS] Getting correct flags for MIPS
Patch by Nitesh Jain

Reviewers: clayborg, ovyalov, emaste.
Subscribers: jaydeep, bhushan, dsanders, mohit.bhakkad, sagar, labath, tberghammer, lldb-commits.
Differential Revision: http://reviews.llvm.org/D10685

llvm-svn: 241045
2015-06-30 06:29:12 +00:00
Greg Clayton 2e59d4fffe More packet reduction when debugging with GDB server.
- Avoid sending the qfThreadInfo, qsThreadInfo packets if we have a stop reply packet with the threads already (save 2 round trip packets)
- Include the qname, qserial and qkind in the JSON info
- Report the qname, qserial and qkind to the thread so it can cache it to avoid many packets on MacOSX and iOS
- Don't clear all discoverable settings when we exec, just the ones we need to saves 1-5 packets for each exec.

llvm-svn: 240988
2015-06-29 20:08:51 +00:00
Pavel Labath c7512fdc1e [NativeProcessLinux] Use lambdas in DoOperation calls
Summary:
This removes a lot of boilerplate, which was needed to execute monitor operations. Previously one
needed do declare a separate class for each operation which would manually capture all needed
arguments, which was very verbose. In addition to less code, I believe this also makes the code
more readable, since now the implementation of the operation can be physically closer to the code
that invokes it.

Test Plan: Code compiles on x86, arm and mips, tests pass on x86 linux.

Reviewers: tberghammer, chaoren

Subscribers: aemerson, lldb-commits

Differential Revision: http://reviews.llvm.org/D10694

llvm-svn: 240772
2015-06-26 10:14:12 +00:00
Ewan Crawford 682e842855 XML register info fix
There are a couple of bugs in the XML register info handling which this patch fixes:

+ conflicting variable names in lambda, both capture list and parameters contains a variable called 'name'.

+ prev_reg_num, which sets the register number, should be incremented after each register is processed.

+ Windows errors regarding empty strings and the 'xi:' prefix disappearing from 'xi:include' node name.

Reviewers: clayborg

Subscribers: lldb-commits, deepak2427

Differential Revision: http://reviews.llvm.org/D10731

llvm-svn: 240768
2015-06-26 09:38:27 +00:00
Greg Clayton 358cf1ea30 Resubmitting 240466 after fixing the linux test suite failures.
A few extras were fixed

- Symbol::GetAddress() now returns an Address object, not a reference. There were places where people were accessing the address of a symbol when the symbol's value wasn't an address symbol. On MacOSX, undefined symbols have a value zero and some places where using the symbol's address and getting an absolute address of zero (since an Address object with no section and an m_offset whose value isn't LLDB_INVALID_ADDRESS is considered an absolute address). So fixing this required some changes to make sure people were getting what they expected. 
- Since some places want to access the address as a reference, I added a few new functions to symbol:
    Address &Symbol::GetAddressRef();
    const Address &Symbol::GetAddressRef() const;

Linux test suite passes just fine now.

<rdar://problem/21494354>

llvm-svn: 240702
2015-06-25 21:46:34 +00:00
Ed Maste a681ea25ed Reduce FreeBSD log spam
The values of four important registers are included in logs for ptrace
PT_GETREGS. Put all four on the same line for a more compact log. Also
use the proper 64-bit register names.

llvm-svn: 240581
2015-06-24 20:02:56 +00:00
Ed Maste 0ded6293c7 Remove SetResumeState from POSIXThread::RefreshStateAfterStop
With the removal of ProcessLinux in r240543 this code is used only on
FreeBSD. FreeBSD isn't affected by whichever issue originally prompted
the addition of SetResumeState, so just remove it.

As discussed on the mailing list (and mentioned in a FIXME comment)
it shouldn't be called there.

llvm-svn: 240550
2015-06-24 16:39:22 +00:00
Ed Maste 4a8d32b733 Remove empty ProcessPOSIX::StopAllThreads
The removal of ProcessLinux in r240543 left only an empty
StopAllThreads (it's not needed on FreeBSD), so just remove it too.

llvm-svn: 240549
2015-06-24 16:24:56 +00:00
Ewan Crawford aa7eda7a9e Proper handling of QNonStop packet response.
Turn non-stop mode off if reply to QNonStop packet isn't an OK.

llvm-svn: 240546
2015-06-24 15:14:26 +00:00
Pavel Labath b36f917854 Remove old local-only linux debugging code
Summary:
Currently, the local-only path fails about 50% of the tests, which means that: a) nobody is using
it; and b) the remote debugging path is much more stable. This commit removes the local-only
linux debugging code (ProcessLinux) and makes remote-loopback the only way to debug local
applications (the same architecture as OSX). The ProcessPOSIX code is moved to the FreeBSD
directory, which is now the only user of this class. Hopefully, FreeBSD will soon move to the new
architecture as well and then this code can be removed completely.

Test Plan: Test suite passes via remote stub.

Reviewers: emaste, vharron, ovyalov, clayborg

Subscribers: tberghammer, emaste, lldb-commits

Differential Revision: http://reviews.llvm.org/D10661

llvm-svn: 240543
2015-06-24 14:43:20 +00:00
Tamas Berghammer 44ff9ccede Improve instruction emulation based stack unwinding on ARM
* Add and fix the emulation of several instruction.
* Disable frame pointer usage on Android.
* Specify return address register for the unwind plan instead of explict
  tracking the value of RA.
* Replace prologue detection heuristics (unreliable in several cases)
  with a logic to follow the branch instructions and restore the CFI
  value based on them. The target address for a branch should have the
  same CFI as the source address (if they are in the same function).
* Handle symbols in ELF files where the symbol size is not specified
  with calcualting their size based on the next symbol (already done
  in MachO files).
* Fix architecture in FuncUnwinders with filling up the inforamtion
  missing from the object file with the architecture of the target.
* Add code to read register wehn the value is set to "IsSame" as it
  meanse the value of a register in the parent frame is the same as the
  value in the current frame.

Differential revision: http://reviews.llvm.org/D10447

llvm-svn: 240533
2015-06-24 11:27:32 +00:00
Greg Clayton 0b90be1c4f Implement the "qSymbol" packet in order to be able to read queue information in debugserver and return the info in the stop reply packets.
A "qSymbol::" is sent when shared libraries have been loaded by hooking into the Process::ModulesDidLoad() function from within ProcessGDBRemote. This function was made virtual so that the ProcessGDBRemote version is called, which then first calls the Process::ModulesDidLoad(), and then it queries for any symbol lookups that the remote GDB server might want to do.

This allows debugserver to request the "dispatch_queue_offsets" symbol so that it can read the queue name, queue kind and queue serial number and include this data as part of the stop reply packet. Previously each thread would have to do 3 memory reads in order to read the queue name.

This is part of reducing the number of packets that are sent between LLDB and the remote GDB server.

<rdar://problem/21494354>

llvm-svn: 240466
2015-06-23 21:27:50 +00:00
Ewan Crawford 76df2881ba Add handling of async notify packets
This patch adds a listener to the AynscThread in ProcessGDBRemote, specifically for dealing with any async notification packets.

From the broadcast our listener receives we can process the notify packet from the event data. A handler function then sets the thread stop info from this packet, and updates lldb by setting the process private state to stopped. Allowing the async thread to go back to sleep and getting the main thread to handle the implications of a state change.

When sending a vCont in nonstop mode we also get a different reply from all-stop mode, an OK response as opposed to a stop reply. So a condition is added to handle this and set the process state without the stop-reply data.

Reviewers: clayborg

Subscribers: lldb-commits, labath, ted, aidan.dodds, deepak2427

Differential Revision: http://reviews.llvm.org/D10544

llvm-svn: 240397
2015-06-23 12:32:06 +00:00
Jaydeep Patil c60c94528c [LLDB][MIPS] MIPS32 branch emulation and single-stepping
SUMMARY:
    This patch implements
      1. Emulation of MIPS32 branch instructions
      2. Enable single-stepping for MIPS32 instructions
      3. Correction in emulation of MIPS64 branch instructions with delay slot
      4. Adjust breakpoint address when breakpoint is hit in a forbidden slot of compact branch instruction
    
    Reviewers: clayborg
    Subscribers: mohit.bhakkad, sagar, bhushan, lldb-commits, emaste, nitesh.jain
    Differential Revision: http://reviews.llvm.org/D10596

llvm-svn: 240373
2015-06-23 03:37:08 +00:00
Chaoren Lin 7a30608026 Revert "Reduced packet counts to the remote GDB server where possible."
This reverts commit 0cc0745ea9c68d7fdcadc9904cee3f13c96dae60.

Due to breakage on Linux build bot:

http://lab.llvm.org:8011/builders/lldb-x86_64-ubuntu-14.04-cmake/builds/3436

llvm-svn: 240371
2015-06-23 03:17:01 +00:00
Greg Clayton ffb2d44ab9 Reduced packet counts to the remote GDB server where possible.
We have been working on reducing the packet count that is sent between LLDB and the debugserver on MacOSX and iOS. Our approach to this was to reduce the packets required when debugging multiple threads. We currently make one qThreadStopInfoXXXX call (where XXXX is the thread ID in hex) per thread except the thread that stopped with a stop reply packet. In order to implement multiple thread infos in a single reply, we need to use structured data, which means JSON. The new jThreadsInfo packet will attempt to retrieve all thread infos in a single packet. The data is very similar to the stop reply packets, but packaged in JSON and uses JSON arrays where applicable. The JSON output looks like:


[
  { "tid":1580681,
    "metype":6,
    "medata":[2,0],
    "reason":"exception",
    "qaddr":140735118423168,
    "registers": {
      "0":"8000000000000000",
      "1":"0000000000000000",
      "2":"20fabf5fff7f0000",
      "3":"e8f8bf5fff7f0000",
      "4":"0100000000000000",
      "5":"d8f8bf5fff7f0000",
      "6":"b0f8bf5fff7f0000",
      "7":"20f4bf5fff7f0000",
      "8":"8000000000000000",
      "9":"61a8db78a61500db",
      "10":"3200000000000000",
      "11":"4602000000000000",
      "12":"0000000000000000",
      "13":"0000000000000000",
      "14":"0000000000000000",
      "15":"0000000000000000",
      "16":"960b000001000000",
      "17":"0202000000000000",
      "18":"2b00000000000000",
      "19":"0000000000000000",
      "20":"0000000000000000"},
    "memory":[
      {"address":140734799804592,"bytes":"c8f8bf5fff7f0000c9a59e8cff7f0000"},
      {"address":140734799804616,"bytes":"00000000000000000100000000000000"}
    ]
  }
]

It contains an array of dicitionaries with all of the key value pairs that are normally in the stop reply packet. Including the expedited registers. Notice that is also contains expedited memory in the "memory" key. Any values in this memory will get included in a new L1 cache in lldb_private::Process where if a memory read request is made and that memory request fits into one of the L1 memory cache blocks, it will use that memory data. If a memory request fails in the L1 cache, it will fall back to the L2 cache which is the same block sized caching we were using before these changes. This allows a process to expedite memory that you are likely to use and it reduces packet count. On MacOSX with debugserver, we expedite the frame pointer backchain for a thread (up to 256 entries) by reading 2 pointers worth of bytes at the frame pointer (for the previous FP and PC), and follow the backchain. Most backtraces on MacOSX and iOS now don't require us to read any memory!

We will try these packets out and if successful, we should port these to lldb-server in the near future. 

<rdar://problem/21494354>

llvm-svn: 240354
2015-06-22 23:12:45 +00:00
Adrian McCarthy a59a7211f0 Load executable module when attaching to process; implement detach from process.
llvm-svn: 240157
2015-06-19 18:26:53 +00:00