1818 Commits

Author SHA1 Message Date
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
Dimitar Vlahovski
ee44a92df6 Revert "Intel(R) Memory Protection Extensions (Intel(R) MPX) support."
This reverts commit rL280668 because the register tests fail on i386
Linux.

I investigated a little bit what causes the failure - there are missing
registers when running 'register read -a'.
This is the output I got at the bottom:
"""
...
Memory Protection Extensions:
      bnd0 = {0x0000000000000000 0x0000000000000000}
      bnd1 = {0x0000000000000000 0x0000000000000000}
      bnd2 = {0x0000000000000000 0x0000000000000000}
      bnd3 = {0x0000000000000000 0x0000000000000000}

unknown:
2 registers were unavailable.
"""

Also looking at the packets exchanged between the client and server:
"""
...
history[308] tid=0x7338 <  19> send packet: $qRegisterInfo4a#d7
history[309] tid=0x7338 < 130> read packet:
$name:bnd0;bitsize:128;offset:1032;encoding:vector;format:vector-uint64;set:Memory
Protection Extensions;ehframe:101;dwarf:101;#48
history[310] tid=0x7338 <  19> send packet: $qRegisterInfo4b#d8
history[311] tid=0x7338 < 130> read packet:
$name:bnd1;bitsize:128;offset:1048;encoding:vector;format:vector-uint64;set:Memory
Protection Extensions;ehframe:102;dwarf:102;#52
history[312] tid=0x7338 <  19> send packet: $qRegisterInfo4c#d9
history[313] tid=0x7338 < 130> read packet:
$name:bnd2;bitsize:128;offset:1064;encoding:vector;format:vector-uint64;set:Memory
Protection Extensions;ehframe:103;dwarf:103;#53
history[314] tid=0x7338 <  19> send packet: $qRegisterInfo4d#da
history[315] tid=0x7338 < 130> read packet:
$name:bnd3;bitsize:128;offset:1080;encoding:vector;format:vector-uint64;set:Memory
Protection Extensions;ehframe:104;dwarf:104;#54
history[316] tid=0x7338 <  19> send packet: $qRegisterInfo4e#db
history[317] tid=0x7338 <  76> read packet:
$name:bndcfgu;bitsize:64;offset:1096;encoding:vector;format:vector-uint8;#99
history[318] tid=0x7338 <  19> send packet: $qRegisterInfo4f#dc
history[319] tid=0x7338 <  78> read packet:
$name:bndstatus;bitsize:64;offset:1104;encoding:vector;format:vector-uint8;#8e
...
"""

The bndcfgu and bndstatus registers don't have the 'Memory Protections
Extension' set. I looked at the code and it seems that that is set
correctly.

So I'm not sure what's the problem or where does it come from.

Also there is a second failure related to something like this in the
tests:
"""
registerSet.GetName().lower()
"""

For some reason the registerSet.GetName() returns None.

llvm-svn: 280703
2016-09-06 11:00:37 +00:00
Valentina Giusti
f105abbc0d Intel(R) Memory Protection Extensions (Intel(R) MPX) support.
Summary:

The Intel(R) Memory Protection Extensions (Intel(R) MPX) associates pointers
to bounds, against which the software can check memory references to
prevent out of bound memory access.

This patch allows accessing the MPX registers:
  * bnd0-3: 128-bit registers to hold the bound values,
  * bndcfgu, bndstatus: 64-bit configuration registers,

This patch also adds read/write tests for the MPX registers in the register
command tests and adds a new subdirectory for MPX specific tests.

Signed-off-by: Valentina Giusti <valentina.giusti@intel.com>

Reviewers: labath, granata.enrico, lldb-commits, clayborg

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D24187

llvm-svn: 280668
2016-09-05 17:43:10 +00:00
Todd Fiala
e77fce0a50 [NFC] Darwin llgs support from Week of Code
This code represents the Week of Code work I did on bringing up
lldb-server LLGS support for Darwin.  It does not include the
Xcode project changes needed, as we don't want to throw that switch
until more support is implemented (i.e. this change is inert, no
build systems use it yet.  I've verified on Ubuntu 16.04, macOS
Xcode and macOS cmake builds).

This change does some minimal refactoring of code that is shared
with the Linux LLGS portion, moving it from NativeProcessLinux into
NativeProcessProtocol.  That code is also used by NativeProcessDarwin.

Current state on Darwin:
* Process launching is implemented.  (Attach is not).
  Launching on devices has not yet been tested (FBS/BKS might
  need a bit of work).
* Inferior waitpid monitoring and communication of exit status
  via MainLoop callback is implemented.
* Memory read/write, breakpoints, thread register context, etc.
  are not yet implemented.  This impacts process stop/resume, as
  the initial launch suspended immediately starts the process
  up and running because it doesn't know it is supposed to remain
  stopped.
* I implemented the equivalent of MachThreadList as
  NativeThreadListDarwin, in anticipation that we might want to
  factor out common parts into NativeThreadList{Protocol} and share
  some code here.  After writing it, though, the fallout from merging
  Mach Task/Process into a single concept plus some other minor
  changes makes the whole NativeThreadListDarwin concept nothing more
  than dead weight.  I am likely going to get rid of this class and
  just manage it directly in NativeProcessDarwin, much like I did
  for NativeProcessLinux.
* There is a stub-out call for starting a STDIO thread.  That will
  go away and adopt the MainLoop pselect-based IOObject reading.

I am developing the fully-integrated changes in the following repo,
which contains the necessary Xcode bits and the glue that enables
lldb-debugserver on a macOS system:

  https://github.com/tfiala/lldb/tree/llgs-darwin

This change also breaks out a few of the lldb-server tests into
their own directory, and adds some $qHostInfo tests (not sure why
I didn't write those tests back when I initially implemented that
on the Linux side).

llvm-svn: 280604
2016-09-04 00:18:56 +00:00
Dimitar Vlahovski
2e50d8edc6 Minidump parsing
Summary:
This is a Minidump parsing code.
There are still some more structures/data streams that need to be added.
The aim ot this is to be used in the implementation of
a minidump debugging plugin that works on all platforms/architectures.
Currently we have a windows-only plugin that uses the WinAPI to parse
the dump files.
Also added unittests for the current functionality.

Reviewers: labath, amccarth

Subscribers: tberghammer, danalbert, srhines, lldb-commits, dschuff

Differential Revision: https://reviews.llvm.org/D23545

llvm-svn: 280356
2016-09-01 11:29:53 +00:00
Pavel Labath
b9739d4090 Revert r280137 and 280139 and subsequent build fixes
The rewrite of StringExtractor::GetHexMaxU32 changes functionality in a way which makes
lldb-server crash. The crash (assert) happens when parsing the "qRegisterInfo0" packet, because
the function tries to drop_front more bytes than the packet contains. It's not clear to me
whether we should consider this a bug in the caller or the callee, but it any case, it worked
before, so I am reverting this until we can figure out what the proper interface should be.

llvm-svn: 280207
2016-08-31 08:43:37 +00:00
Pavel Labath
1e3b086749 Revert r280200 and put it a proper fix
PeekChar returns a character, we want the whole string there.

llvm-svn: 280204
2016-08-31 07:49:37 +00:00
Pavel Labath
30ff4b4851 Fix lldb build on Mac.
Summary:
e80f43fd78
greatly improved an API, but missed one more occurence of legacy usage.

This leads to:
  if (extractor.GetHexBytes(&payload_bytes[0], payload_bytes.size(), '\xdd') != payload_bytes.size())
                                ~~~~~~~~~~~~~~~~~~~~~                                          ^~~~~~
  /lldb/include/lldb/Utility/StringExtractor.h:151:5: note: 'GetHexBytes' declared here

Reviewers: zturner

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D24064
Author: Taras Tsugrii <ttsugrii@fb.com>

llvm-svn: 280202
2016-08-31 07:42:38 +00:00
Sylvestre Ledru
2c07a069b8 Update the Linux code to reflect the changes done by zturner in r280139
llvm-svn: 280200
2016-08-31 07:16:56 +00:00
Zachary Turner
2d240d00da A few minor stylistic cleanups in StringExtractor.
Makes Peek() return a StringRef instead of a const char*.

This leads to a few callers of Peek() being able to be made a
little nicer (for example using StringRef member functions instead
of c-style strncmp and related functions) and generally safer
usage.

llvm-svn: 280139
2016-08-30 19:47:05 +00:00
Zachary Turner
d08f09c113 Convert some StringExtractor functions to accept MutableArrayRefs.
MutableArrayRef<T> is essentially a safer version of passing around
(T*, length) pairs and provides some convenient functions for working
with the data without having to manually manipulate indices.

This is a minor NFC.

llvm-svn: 280123
2016-08-30 18:12:11 +00:00
Pavel Labath
5c95ee4dd8 Revert "gdb-remote: Make the sequence mutex non-recursive"
This reverts commit r279725 as it breaks "dynamic register size" feature of mips.

llvm-svn: 280088
2016-08-30 13:56:11 +00:00
Pavel Labath
e1c716c36c Fix fallout from the GetNameColonValue() refactor (r280000)
This fixes the linux test suite.

llvm-svn: 280074
2016-08-30 11:17:00 +00:00
Zachary Turner
54695a339f Convert GetNameColonValue to return StringRefs.
StringExtractor::GetNameColonValue() looks for a substring of the
form "<name>:<value>" and returns <name> and <value> to the caller.
This results in two unnecessary string copies, since the name and
value are not translated in any way and simply returned as-is.

By converting this to return StringRefs we can get rid of hundreds
of string copies.

llvm-svn: 280000
2016-08-29 19:58:14 +00:00
Zachary Turner
70a5ef15bd Fix some build bot breakages.
There was some code that was ifdef'ed out that I didn't catch
in my earlier patch.

llvm-svn: 279920
2016-08-27 16:38:11 +00:00
Zachary Turner
26709df81d Convert some functions to use StringRef instead of c_str, len
This started as an effort to change StringExtractor to store a
StringRef internally instead of a std::string.  I got that working
locally with just 1 test failure which I was unable to figure out the
cause of.  But it was also a massive changelist due to a trickle
down effect of changes.

So I'm starting over, using what I learned from the first time to
tackle smaller, more isolated changes hopefully leading up to
a full conversion by the end.

At first the changes (such as in this CL) will seem mostly
a matter of preference and pointless otherwise.  However, there
are some places in my larger CL where using StringRef turned 20+
lines of code into 2, drastically simplifying logic.  Hopefully
once these go in they will illustrate some of the benefits of
thinking in terms of StringRef.

llvm-svn: 279917
2016-08-27 15:52:29 +00:00
Pavel Labath
0faf37333c gdb-remote: Make the sequence mutex non-recursive
Summary:
This is a preparatory commit for D22914, where I'd like to replace this mutex by an R/W lock
(which is also not recursive). This required a couple of changes:
- The only caller of Read/WriteRegister, GDBRemoteRegisterContext class, was already acquiring
  the mutex, so these functions do not need to. All functions which now do not take a lock, take
  an lock argument instead, to remind the caller of this fact.
- GetThreadSuffixSupported() was being called from locked and unlocked contexts (including
  contexts where the process was running, and the call would fail if it did not have the result
  cached). I have split this into two functions, one which computes the thread suffix support and
  caches it (this one always takes the lock), and another, which returns the cached value (and
  never needs to take the lock). This feels quite natural as ProcessGdbRemote was already
  pre-caching this value at the start.

Reviewers: clayborg

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D23802

llvm-svn: 279725
2016-08-25 08:34:57 +00:00
Pavel Labath
849cc1ae57 Fix a crash in GDBRemoteCommunicationClient::GetSupportedStructuredDataPlugins
The function was attempting to write the reply to the log even if the reply was empty.

llvm-svn: 279513
2016-08-23 12:10:09 +00:00
Pavel Labath
69dac575d3 Fix 32-bit builds after r279232
GetByteSize() of a DataBuffer returns a uint64_t (it probably shouldn't), which isn't implicitly
convertible to size_t.

llvm-svn: 279238
2016-08-19 13:14:13 +00:00
Pavel Labath
b42b48e051 Remove the last manually constructed packet from gdb-remote register context + small refactor
Summary:
The tricky part here was that the exisiting implementation of WriteAllRegisters was expecting
hex-encoded data (as that was what the first implementation I replaced was using, but here we had
binary data to begin with. I thought the read/write register functions would be more useful if
they handled the hex-encoding themselves (all the other client functions provide the responses in
a more-or-less digested form). The read functions return a DataBuffer, so they can allocate as
much memory as they need to, while the write functions functions take an llvm::ArrayRef, as that
can be constructed from pretty much anything.

Reviewers: clayborg

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D23659

llvm-svn: 279232
2016-08-19 12:31:49 +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
Pavel Labath
83082a0337 gdb-remote: Remove manual locking from GetShlibInfoAddr
The function can simply call the non-NoLock version of the SendPacket function and let it do the
locking.

llvm-svn: 279070
2016-08-18 14:33:55 +00:00
Pavel Labath
27402d2a12 Move QSyncThreadState packet generation to the gdb-remote client
llvm-svn: 279057
2016-08-18 12:32:41 +00:00
Pavel Labath
4b6f9591d3 gdb-remote: Centralize thread specific packet handling
Summary:
Before this, each function had a copy of the code which handled appending of the thread suffix to
the packet (or using $Hg instead). I have moved that code into a single function and made
everyone else use that. The function takes the partial packet as a StreamString rvalue reference,
to avoid a copy and to remind the users that the packet will have undeterminate contents after
the call.

This also fixes the incorrect formatting of the QRestoreRegisterState packet in case thread
suffix is not supported.

Reviewers: clayborg

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D23604

llvm-svn: 279040
2016-08-18 08:30:03 +00:00
Pavel Labath
d43ae376d4 Remove manual packet construction from GDBRemoteRegisterContext::SetPrimordialRegister
llvm-svn: 278916
2016-08-17 09:12:21 +00:00
Pavel Labath
56d7262b69 Move packet construction from GDBRemoteRegisterContext go the communication class
Summary:
When saving/restoring registers the GDBRemoteRegisterContext class was manually constructing
the register save/restore packets. This creates appropriate helper functions in
GDBRemoteCommunicationClient, and switches the class to use those. It also removes what a
duplicate packet send in some of those functions, a thing that I can only attribute to a bad
merge artefact.

I also add a test framework for testing gdb-remote client functionality and add tests for the new
functions I introduced. I'd like to be able to test the register context changes in isolation as
well, but currently there doesn't seem to be a way to reasonably construct a standalone register
context object, so we'll have to rely on the end-to-end tests to verify that.

Reviewers: clayborg

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D23553

llvm-svn: 278915
2016-08-17 08:53:31 +00:00
Pavel Labath
5a123c4e37 Remove GetThreadSuffixSupported from GDBRemoteCommunication **base** class
Despite its comment, the function is only used in the Client class, and its presence was merely
complicating mock implementation in unit tests.

llvm-svn: 278785
2016-08-16 09:36:29 +00:00
Pavel Labath
b3d1290c44 Fixup r278524 for non-apple targets
The commit started passing a nullptr port into GDBRemoteCommunication::StartDebugserverProcess.
The function was mostly handling the null value correctly, but it one case it did not check it's
value before assigning to it. Fix that.

llvm-svn: 278662
2016-08-15 09:17:13 +00:00
Ed Maste
0767b40e25 elf-core: set powerpc vector byte order correctly
It was being set to the fp reg set's byte order due to an apparent
copy-and-pasteo.                                                   

llvm-svn: 278625
2016-08-14 11:30:11 +00:00
Zachary Turner
bd22bf26cb Fix build on Windows.
llvm-svn: 278526
2016-08-12 16:52:31 +00:00
Greg Clayton
c6c420fca1 Switch over to using socketpair for local debugserver connections as they are twice as fast as TCP sockets (on macOS at least).
This change opens a socket pair and passes the second socket pair file descriptor down to the debugserver binary using a new option: "--fd=N" where N is the file descriptor. This file descriptor gets passed via posix_spawn() so that there is no need to do any bind/listen or bind/accept calls and eliminates the hanshake unix socket that is used to pass the result of the actual port that ends up being used so it can save time on launch as well as being faster.

This is currently only enabled on __APPLE__ builds. Other OSs should try modifying the #define from ProcessGDBRemote.cpp but the first person will need to port the --fd option over to lldb-server. Any OSs that enable USE_SOCKETPAIR_FOR_LOCAL_CONNECTION in their native builds can use the socket pair stuff. The #define is Apple only right now, but looks like:

#if defined (__APPLE__)
#define USE_SOCKETPAIR_FOR_LOCAL_CONNECTION 1
#endif

<rdar://problem/27814880> 

llvm-svn: 278524
2016-08-12 16:46:18 +00:00
Todd Fiala
e1cfbc7942 Decoupled Options from CommandInterpreter.
Options used to store a reference to the CommandInterpreter instance
in the base Options class.  This made it impossible to parse options
independent of a CommandInterpreter.

This change removes the reference from the base class.  Instead, it
modifies the options-parsing-related methods to take an
ExecutionContext pointer, which the options may inspect if they need
to do so.

Closes https://reviews.llvm.org/D23416
Reviewers: clayborg, jingham

llvm-svn: 278440
2016-08-11 23:51:28 +00:00
Pavel Labath
9ba9dfdd02 Make sure files include what they use (part 2/2)
This makes lldb still compile on linux after a project-wide clang-format

llvm-svn: 278335
2016-08-11 14:12:10 +00:00
Pavel Labath
4dbab21354 Remove a double send of eRunPacketSent event
I accidentaly added the send both to the base class and the derived class in my refactor. Fix
that.

llvm-svn: 278325
2016-08-11 09:22:22 +00:00
Pavel Labath
dc2b3b7ea8 Make sure files include what they use (part 1/N)
preparation for the big clang-format.

llvm-svn: 278222
2016-08-10 13:30:20 +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
Pavel Labath
8c1b6bd7d2 Reapply "Rewrite gdb-remote's SendContinuePacketAndWaitForResponse"
Resumbitting the commit after fixing the following problems:
- broken unit tests on windows: incorrect gtest usage on my part (TEST vs. TEST_F)
- the new code did not correctly handle the case where we went to interrupt the process, but it
  stopped due to a different reason - the interrupt request would remain queued and would
  interfere with the following "continue". I also added a unit test for this case.

This reapplies r277156 and r277139.

llvm-svn: 278118
2016-08-09 12:04:46 +00:00
Greg Clayton
5b22f4a6f7 Fix more RegisterInfo initialization issues and quiet hundreds of warnings.
llvm-svn: 278063
2016-08-08 22:48:07 +00:00
Greg Clayton
52930b5f4a Fix printf warnings.
llvm-svn: 278061
2016-08-08 22:16:03 +00:00
Greg Clayton
1386c6ceae Fix RegisterInfo initializers to have all the required initializers after recent changes. This quiets a few hundred warnings on MacOSX.
llvm-svn: 278060
2016-08-08 22:15:35 +00:00
Pavel Labath
142f4f76be Fix uninitialized field warnings in GDBRemoteRegisterContext
also take the opportunity to replace NULL with nullptr and add clang-format guards to prevent it
from messing up the nice table there.

llvm-svn: 278005
2016-08-08 13:38:33 +00:00
Pavel Labath
1eb0d42a1b Remove Android.h
It only contained a reimplementation of std::to_string, which I have replaced with usages of
pre-existing llvm::to_string (also, injecting members into the std namespace is evil).

llvm-svn: 278000
2016-08-08 12:54:36 +00:00
Pavel Labath
c923a3dc00 Remove SYS_tgkill from Android.h
instead, use __NR_tgkill directly, which seems to be the preferred form in the codebase anyway.

llvm-svn: 277999
2016-08-08 12:40:11 +00:00
Nitesh Jain
52b6cc5d5f [LLVM][MIPS] Fix FPU Size Based on Dynamic FR.
Reviewers: jingham, clayborg

Subscribers: jaydeep, bhushan, mohit.bhakkad, slthakur, lldb-commits, emaste, nemanjai, labath, sdardis

Differential Revision: https://reviews.llvm.org/D20357

llvm-svn: 277343
2016-08-01 13:45:51 +00:00
Pavel Labath
4cb699260c Revert "Rewrite gdb-remote's SendContinuePacketAndWaitForResponse"
This reverts commit r277139, because:
- broken unittest on windows (likely typo on my part)
- seems to break TestCallThatRestart (needs investigation)

llvm-svn: 277154
2016-07-29 15:41:52 +00:00
Dimitar Vlahovski
023dd64f25 Add/fix support for i386 elf core files
Summary:
There were places in the code, assuming(hardcoding) offsets
and types that were only valid for the x86_64 elf core file format.

The NT_PRSTATUS and NT_PRPSINFO structures are with the 64 bit layout.
I have reused them and parse i386 files manually, and fill them in the
same struct.

Also added some error handling during parsing that checks if the
available bytes in the buffer are enough to fill the structures.

The i386 core file test case now passes.

For reference on the structures layout, I generally used the
source of binutils (bfd, readelf)

Bug: https://llvm.org/bugs/show_bug.cgi?id=26947

Reviewers: labath

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D22917

llvm-svn: 277140
2016-07-29 13:18:09 +00:00
Pavel Labath
e768c4b858 Rewrite gdb-remote's SendContinuePacketAndWaitForResponse
SendContinuePacketAndWaitForResponse was huge function with very complex interactions with
several other functions (SendAsyncSignal, SendInterrupt, SendPacket). This meant that making any
changes to how packet sending functions and threads interact was very difficult and error-prone.

This change does not add any functionality yet, it merely paves the way for future changes. In a
follow-up, I plan to add the ability to have multiple query packets in flight (i.e.,
request,request,response,response instead of the usual request,response sequences) and use that
to speed up qModuleInfo packet processing.

Here, I introduce two special kinds of locks: ContinueLock, which is used by the continue thread,
and Lock, which is used by everyone else. ContinueLock (atomically) sends a continue packet, and
blocks any other async threads from accessing the connection. Other threads create an instance of
the Lock object when they want to access the connection. This object, while in scope prevents the
continue from being send. Optionally, it can also interrupt the process to gain access to the
connection for async processing.

Most of the syncrhonization logic is encapsulated within these two classes. Some of it still
had to bleed over into the SendContinuePacketAndWaitForResponse, but the function is still much
more manageable than before -- partly because of most of the work is done in the ContinueLock
class, and partly because I have factored out a lot of the packet processing code separate
functions (this also makes the functionality more easily testable). Most importantly, there is
none of syncrhonization code in the async thread users -- as far as they are concerned, they just
need to declare a Lock object, and they are good to go (SendPacketAndWaitForResponse is now a
very thin wrapper around the NoLock version of the function, whereas previously it had over 100
lines of synchronization code).  This will make my follow up changes there easy.

I have written a number of unit tests for the new code and I have ran the test suite on linux and
osx with no regressions.

Subscribers: tberghammer

Differential Revision: https://reviews.llvm.org/D22629

llvm-svn: 277139
2016-07-29 13:10:02 +00:00
Jason Molenda
4fa5041225 Small refinement on the memory segment support in core files that
Greg added in r272276 -- when working with a non-user-process mach-o
core file, force the permissions to readable + executable, else the
unwinder can stop backtracing early if it gets a pc value in a segment
that it thinks is non-executable.
<rdar://problem/27138456> 
<rdar://problem/27462904> 

llvm-svn: 277065
2016-07-28 22:43:10 +00:00