Commit Graph

11827 Commits

Author SHA1 Message Date
Pavel Labath 3d4f7655e7 Remove usage of usleep in generic code
This function is not portable, and there are only a handful of usages of
it anyway. Replacing it with std::this_thread::sleep_for enables us to
get rid of the compatibility code in PosixApi.h.

llvm-svn: 367814
2019-08-05 08:23:25 +00:00
Fangrui Song d9b948b6eb Rename F_{None,Text,Append} to OF_{None,Text,Append}. NFC
F_{None,Text,Append} are kept for compatibility since r334221.

llvm-svn: 367800
2019-08-05 05:43:48 +00:00
Shafik Yaghmour fa5c340ea1 Fix ClangASTContext::CreateParameterDeclaration to not call addDecl
Summary:
The change https://reviews.llvm.org/D55575 modified ClangASTContext::CreateParameterDeclaration to call decl_ctx->addDecl(decl); this caused a regression since the existing code in DWARFASTParserClang::ParseChildParameters is called with the containing DeclContext. So when end up with cases where we are parsing a parameter for a member function and the parameter is added to the CXXRecordDecl as opposed to the CXXMethodDecl. This example is given in the regression test TestBreakpointInMemberFuncWNonPrimitiveParams.py which without this fix in a modules build leads to assert on setting a breakpoint in a member function with non primitive parameters. This scenario would be common when debugging LLDB or clang.

Differential Revision: https://reviews.llvm.org/D65414

llvm-svn: 367726
2019-08-02 21:41:50 +00:00
Shafik Yaghmour c5d4014535 [Formatters] Temporarily disable libc++ std::function formatter due to performance issue
Summary: We have been seeing increased reports of performance issue around large project and formatting std::function variables especially in functions signatures in back traces. There are some possible fixes but exploring those fixes may take time and it is better to temporarily disable the formatter due to its impact and re-enable it once we have a fix.

Differential Revision: https://reviews.llvm.org/D65666

llvm-svn: 367701
2019-08-02 18:16:04 +00:00
Joseph Tremoulet 31e6dbe1c6 Fix PC adjustment in StackFrame::GetSymbolContext
Summary:
Update StackFrame::GetSymbolContext to mirror the logic in
RegisterContextLLDB::InitializeNonZerothFrame that knows not to do the
pc decrement when the given frame is a signal trap handler frame or the
parent of one, because the pc may not follow a call in these frames.
Accomplish this by adding a behaves_like_zeroth_frame field to
lldb_private::StackFrame, set to true for the zeroth frame, for
signal handler frames, and for parents of signal handler frames.

Also add logic to propagate the signal handler flag from UnwindPlan to
the FrameType on the RegisterContextLLDB it generates, and factor out a
helper to resolve symbol and address range for an Address now that we
need to invoke it in four places.

Reviewers: jasonmolenda, clayborg, jfb

Reviewed By: jasonmolenda

Subscribers: labath, dexonsmith, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D64993

llvm-svn: 367691
2019-08-02 16:53:42 +00:00
Pavel Labath 23f70e8359 SymbolVendor: Introduce Module::GetSymbolFile
Summary:
This is the next step in avoiding funneling all SymbolFile calls through
the SymbolVendor. Right now, it is just a convenience function, but it
allows us to update all calls to SymbolVendor functions to access the
SymbolFile directly. Once all call sites have been updated, we can
remove the GetSymbolVendor member function.

This patch just updates the calls to GetSymbolVendor, which were calling
it just so they could fetch the underlying symbol file. Other calls will
be done in follow-ups.

Reviewers: JDevlieghere, clayborg, jingham

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D65435

llvm-svn: 367664
2019-08-02 08:16:35 +00:00
Jonas Devlieghere e063eccc19 Format OptionEnumValueElement (NFC)
Reformat OptionEnumValueElement to make it easier to distinguish between
its fields. This also removes the need to disable clang-format for these
arrays.

Differential revision: https://reviews.llvm.org/D65489

llvm-svn: 367638
2019-08-02 00:18:44 +00:00
Harlan Haskins 84586c1423 [clang] Change FileManager to use llvm::ErrorOr instead of null on failure
Summary:
Currently, clang's FileManager uses NULL as an indicator that a particular file
did not exist, but would not propagate errors like permission issues. Instead,
teach FileManager to use llvm::ErrorOr internally and return rich errors for
failures.

Reviewers: arphaman, bruno, martong, shafik

Subscribers: nemanjai, kbarton, MaskRay, jkorous, dexonsmith, kadircet, jsji, cfe-commits, lldb-commits

Tags: #clang, #lldb

Differential Revision: https://reviews.llvm.org/D65534

llvm-svn: 367618
2019-08-01 21:32:04 +00:00
Raphael Isemann 0a39368b6c [lldb][NFC] Make ClangDiagnostic::m_fixit_vec private
llvm-svn: 367542
2019-08-01 11:05:47 +00:00
Jonas Devlieghere 70df51b8a9 [Reproducers] Force replay in synchronous mode.
Replaying a reproducer in asynchronous mode never makes sense. This
patch disables asynchronous mode during replay.

Differential revision: https://reviews.llvm.org/D65547

llvm-svn: 367494
2019-07-31 23:34:45 +00:00
Jonas Devlieghere 970a57907e [GDBRemote] Reflow comments and improve docs.
Improved the GDB client base documentation while I was reading through
it. Looks like it got messed up during the automatic comment reflow a
while ago.

llvm-svn: 367481
2019-07-31 20:47:44 +00:00
Alex Langford 70402bfc46 [API] Remove use of ClangASTContext from SBTarget
Summary:
The methods to find types in a Target aren't clang specific and are
pretty generalizable to type systems. Additionally, to support some of
the use cases in SBTarget, I've added a "GetScratchTypeSystems" method
to Target to support getting all type systems for a target we are
debugging.

Differential Revision: https://reviews.llvm.org/D64964

llvm-svn: 367480
2019-07-31 20:47:38 +00:00
Jonas Devlieghere 07b1a2b9ae Fix completion for functions in anonymous namespaces
I was going through some of the old bugs and came across PR21069 which I
was able to reproduce. The issue is that we match the regex `^foo`
against the `DW_AT_name` in the DWARF, which for our anonymous function
is indeed `foo`. However, when we get the function name from the symbol
context, the result is `(anonymous namespace)::foo()`. This throws off
completions, which assumes that it's appending to whatever is already
present on the input, resulting in a bogus
`b fooonymous\ namespace)::foo()`.

Bug report: https://llvm.org/PR21069

Differential revision: https://reviews.llvm.org/D65498

llvm-svn: 367455
2019-07-31 17:58:00 +00:00
Greg Clayton af44f18ad6 Don't crash when pass by value struct has no definition.
llvm-svn: 367441
2019-07-31 16:24:55 +00:00
Pavel Labath a9d58436af Fix issues with inferior stdout coming out of order
Summary:
We've had a bug where two pieces of code, executing on two threads were
attempting to write inferior output simultaneously. The first one was in
Debugger::HandleProcessEvent, which handled the cases where stdout was
coming while the process was running. The second was in
CommandInterpreter::IOHandlerInputComplete, which was ensuring that any
output is printed before the command which caused process to run
terminates.

Both of these things make sense, but the fact they were implemented as
two independent functions without any synchronization meant that race
conditions could occur (e.g. both threads call process->GetSTDOUT, get
two chunks of data, but then end up calling stream->Write in opposite
order). This was most apparent in situations where a process quickly
writes a bunch of output and then exits (as all our register tests do).

This patch adds a mutex to ensure that stdout forwarding happens
atomically. It also refactors a code somewhat in order to reduce code
duplication.

Reviewers: clayborg, jingham

Subscribers: jfb, mgorny, lldb-commits

Differential Revision: https://reviews.llvm.org/D65152

llvm-svn: 367418
2019-07-31 12:06:50 +00:00
Tatyana Krasnukha e98b4188dc [ProcessWindows] Choose a register context file by preprocessor
Replaced Cmake option based check with the preprocessor macro as CMAKE_SYSTEM_PROCESSOR doesn't work as expected on Windows.

Fixes llvm.org/pr42724

Differential Revision: https://reviews.llvm.org/D65409

llvm-svn: 367414
2019-07-31 12:00:30 +00:00
Pavel Labath e84f78412b Add llvm-style RTTI to ObjectFile hierarchy
Summary:
On the heels of D62934, this patch uses the same approach to introduce
llvm RTTI support to the ObjectFile hierarchy. It also replaces the
existing uses of GetPluginName doing run-time type checks with
llvm::dyn_cast and friends.

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

Reviewers: xiaobai, JDevlieghere, espindola

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

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

llvm-svn: 367413
2019-07-31 11:57:34 +00:00
Pavel Labath d2deeb4490 SymbolVendor: Remove the object file member variable
Summary:
The last responsibility of the SymbolVendor was to hold an owning
reference to the object file (in case symbols are being read from a
different file than the main module). As SymbolFile classes already hold
a non-owning reference to the object file, we can easily remove this
responsibility of the SymbolVendor by making the SymbolFile reference
owning.

Reviewers: JDevlieghere, clayborg, jingham

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D65401

llvm-svn: 367392
2019-07-31 08:25:25 +00:00
Richard Trieu 33cdbff2a7 Change '|' to '&' in conditional.
Bitwise-or with a non-zero constant will always evaluate to true.  Switch to
bitwise-and which will only evalute to true if the specified bit is set in the
other operand.

llvm-svn: 367386
2019-07-31 04:41:05 +00:00
Jonas Devlieghere b22860da61 [CompletionRequest] Remove unimplemented members.
Completion requests have two fields that are essentially unimplemented:
`m_match_start_point` and `m_max_return_elements`. This would've been
okay, if it wasn't for the fact that this caused a bunch of useless
parameters to be passed around. Occasionally there would be a comment or
assert saying that they are not supported. This patch removes them.

llvm-svn: 367385
2019-07-31 03:48:29 +00:00
Jonas Devlieghere 175f093090 [StringList] Change LongestCommonPrefix API
When investigating a completion bug I got confused by the API.
LongestCommonPrefix finds the longest common prefix of the strings in
the string list. Instead of returning that string through an output
argument, just return it by value.

llvm-svn: 367384
2019-07-31 03:26:10 +00:00
Alex Langford 0e252e38ef [Symbol] Use llvm::Expected when getting TypeSystems
Summary:
This commit achieves the following:
- Functions used to return a `TypeSystem *` return an
  `llvm::Expected<TypeSystem *>` now. This means that the result of a call
  is always checked, forcing clients to move more carefully.
- `TypeSystemMap::GetTypeSystemForLanguage` will either return an Error or a
  non-null pointer to a TypeSystem.

Reviewers: JDevlieghere, davide, compnerd

Subscribers: jdoerfert, lldb-commits

Differential Revision: https://reviews.llvm.org/D65122

llvm-svn: 367360
2019-07-30 22:12:34 +00:00
Alex Langford 0723173114 [SymbolFile] SymbolFileDWARF::ParseLineTable should lock its module
As of svn rL367298, SymbolFileDWARF locks the module in many cases where
it needs to parse some aspect of the DWARF symbol file.
SymbolFileDWARF::ParseLineTable needs to lock the module because
SymbolVendor::ParseLineTable no longer locks it.

llvm-svn: 367358
2019-07-30 21:22:17 +00:00
Jonas Devlieghere 130ec06843 [Reproducers] Fix incorrect help message
The help message mentioned the `log` command (probably because I copied
it from there originally).

llvm-svn: 367338
2019-07-30 18:06:38 +00:00
Raphael Isemann e010f6bab3 [lldb] Fix crash when tab-completing in multi-line expr
Summary:
Tab completing inside the multiline expression command can cause LLDB to crash. The easiest way
to do this is to go inside a frame with at least one local variable and then try to complete:

    (lldb) expr
    1. a[tab]

Reason for this was some mixup when we calculate the cursor position. Obviously we should calculate
the offset inside the string by doing 'end - start', but we are doing 'start - end' (which causes the offset to
become -1 which will lead to some out-of-bounds reading).

Fixes rdar://51754005

I don't see any way to test this as the *multiline* expression completion is completely untested at the moment
and I don't think we have any existing code for testing infrastructure for it.

Reviewers: shafik, davide, labath

Reviewed By: labath

Subscribers: abidh, lldb-commits, davide, clayborg, labath

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D64995

llvm-svn: 367308
2019-07-30 12:31:24 +00:00
Pavel Labath 5c43ffd614 PECOFF: Fix a "memset clearing an object of non-trivial type" warning
This time, the warning pointed to an actual problem, because the
coff_opt_header structure contained a std::vector. I guess this happened
to work because the all-zero state was a valid representation of an
empty vector, but its not a good idea to rely on that.

I remove the memset, and have the structure clear its members in the
constructor instead.

llvm-svn: 367299
2019-07-30 08:42:42 +00:00
Pavel Labath 656ddeb2b7 SymbolVendor: Move locking into the Symbol Files
Summary:
The last bit of functionality in SymbolVendor passthrough functions is
the locking the module mutex. While it may be nice doing the locking in
a central place, we weren't really succesful in doing that right now,
because some SymbolFile function could still be called without going
through the SymbolVendor. This meant in SymbolFileDWARF (the only
battle-tested symbol file implementation) roughly a half of the
functions was taking additional locks and another half was asserting
that the lock is already held. By making the SymbolFile responsible for
locking, we can at least make the situation in SymbolFileDWARF more
consistent.

Reviewers: clayborg, JDevlieghere, jingham, jdoerfert

Subscribers: aprantl, lldb-commits

Differential Revision: https://reviews.llvm.org/D65329

llvm-svn: 367298
2019-07-30 08:20:05 +00:00
JF Bastien 268a83e39c [NFC] avoid AlignedCharArray in lldb
As discussed in D65249, don't use AlignedCharArray or std::aligned_storage. Just use alignas(X) char Buf[Size];. This will allow me to remove AlignedCharArray entirely, and works on the current minimum version of Visual Studio.

llvm-svn: 367275
2019-07-29 23:17:08 +00:00
Jonas Devlieghere 96b44c77f8 [Reproducers] Pass FileCollector around as a shared_ptr (NFC)
Instead of passing the FileCollector around as a reference or raw
pointer, use a shared_ptr. This change's motivation is twofold. First it
adds compatibility for the newly added `FileCollectorFileSystem`.
Secondly, it addresses a lifetime issue we only see when LLDB is used
from Xcode, where a reference to the FileCollector outlives the
reproducer instance.

llvm-svn: 367258
2019-07-29 20:54:02 +00:00
Jordan Rupprecht 6a253d378b [lldb] Qualify includes of Properties[Enum].inc files. NFC
Summary:
This is a bit more explicit, and makes it possible to build LLDB without
varying the -I lines per-directory.
(The latter is useful because many build systems only allow this to be
configured per-library, and LLDB is insufficiently layered to be split into
multiple libraries on stricter build systems).

(My comment on D65185 has some more context)

Reviewers: JDevlieghere, labath, chandlerc, jdoerfert

Reviewed By: labath

Subscribers: mgorny, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D65397

Patch by Sam McCall!

llvm-svn: 367241
2019-07-29 17:22:10 +00:00
Jonas Devlieghere a8ea595509 [lldb] Also include the array definition in Properties.inc
Right now our Properties.inc only generates the initializer for the
options list but not the array declaration boilerplate around it. As the
array definition is identical for all arrays, we might as well also let
the Properties.inc generate it alongside the initializers.

Unfortunately we cannot do the same for enums, as there's this magic
ePropertyExperimental, which needs to come at the end to be interpreted
correctly. Hopefully we can get rid of this in the future and do the
same for the property enums.

Differential revision: https://reviews.llvm.org/D65353

llvm-svn: 367238
2019-07-29 16:41:30 +00:00
Pavel Labath c2409baa66 SymbolVendor: Make SectionAddressesChanged a passthrough
Summary:
This moves the implementation of the function into the SymbolFile class,
making it possible to excise the SymbolVendor passthrough functions in
follow-up patches.

Reviewers: clayborg, jingham, JDevlieghere

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D65266

llvm-svn: 367231
2019-07-29 15:53:36 +00:00
Raphael Isemann 822c58704b [lldb][NFC] Remove DiagnosticManager::CopyDiagnostics
The Diagnostic class in LLDB is suppossed to be inherited from,
so just copying the diagnostics like this is wrong. The function
is also unused, so lets just get rid of it instead of creating
some cloning facility for it.

llvm-svn: 367201
2019-07-29 07:37:17 +00:00
Raphael Isemann bd68a052f2 [lldb] Also include the array definition in CommandOptions.inc
Summary:
Right now our CommandOptions.inc only generates the initializer for the options list but
not the array declaration boilerplate around it. As the array definition is identical for all arrays,
we might as well also let the CommandOptions.inc generate it alongside the initializers.

This patch will also allow us to generate additional declarations related to that option list in
the future (e.g. a enum class representing the specific options which would make our
handling code less prone).

This patch also fixes a few option tables that didn't follow our naming style.

Reviewers: JDevlieghere

Reviewed By: JDevlieghere

Subscribers: abidh, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D65331

llvm-svn: 367186
2019-07-28 06:24:07 +00:00
Jonas Devlieghere d4044aad66 [TableGen] Fix stale include paths
This worked locally because the include files were not regenerated, but
fails when performing a clean build.

llvm-svn: 367152
2019-07-26 20:55:07 +00:00
Jonas Devlieghere 01f277e2db [TableGen] Move core properties into a separate file (NFC)
With the plugins having their own tablgen file, it makes sense to split
off the core properties as well.

llvm-svn: 367140
2019-07-26 18:14:12 +00:00
Jonas Devlieghere 463a48e416 [TableGen] Move target properties into a separate file (NFC)
With the plugins having their own tablgen file, it makes sense to split
off the target properties as well.

llvm-svn: 367139
2019-07-26 18:14:08 +00:00
Jonas Devlieghere 7070a0b02a [TableGen] Move interpreter properties into a separate file (NFC)
With the plugins having their own tablgen file, it makes sense to split
off the interpreter properties as well.

llvm-svn: 367138
2019-07-26 18:14:04 +00:00
Pavel Labath d67b550df5 DWARF: Improve type safety or range lists parsing
Delete the abstract GetOffset function, which is only defined for
rnglists entries. Instead fix up entries which refer to the range list
classes so that one can statically know that he is dealing with the
rnglists section and call the function that way.

llvm-svn: 367106
2019-07-26 13:15:28 +00:00
Raphael Isemann 0ab0bb91aa [lldb] Don't dynamically allocate the posix option validator.
We dynamically allocate the option validator which means we
can't mark this list of OptionDefinitions as constexpr. It's also
more complicated than necessary.

llvm-svn: 367102
2019-07-26 11:46:21 +00:00
Pavel Labath fcdceab7e1 Fix some "control reaches end of non-void function" warnings
llvm-svn: 367095
2019-07-26 09:38:23 +00:00
Fangrui Song 20db94b7b3 ObjectFileELF: Use llvm::JamCRC to refactor CRC32 computation
Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D65318

llvm-svn: 367090
2019-07-26 08:33:36 +00:00
Pavel Labath 84a6856928 SymbolVendor: Move Symtab construction into the SymbolFile
Summary:
Instead of having SymbolVendor coordinate Symtab construction between
Symbol and Object files, make the SymbolVendor function a passthrough,
and put all of the logic into the SymbolFile.

Reviewers: clayborg, JDevlieghere, jingham, espindola

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

Differential Revision: https://reviews.llvm.org/D65208

llvm-svn: 367086
2019-07-26 07:03:28 +00:00
Jonas Devlieghere a5db339cda [CMake] Add TableGen dependency to lldbInterpreter.
lldbInterpreter depends on LLDBPropertiesGen and LLDBPropertiesEnumGen.

llvm-svn: 367073
2019-07-25 22:56:59 +00:00
Jonas Devlieghere 971f9ca612 Let tablegen generate property definitions
Property definitions are currently defined in a PropertyDefinition array
and have a corresponding enum to index in this array. Unfortunately this
is quite error prone. Indeed, just today we found an incorrect merge
where a discrepancy between the order of the enum values and their
definition caused the test suite to fail spectacularly.

Tablegen can streamline the process of generating the property
definition table while at the same time guaranteeing that the enums stay
in sync. That's exactly what this patch does. It adds a new tablegen
file for the properties, building on top of the infrastructure that
Raphael added recently for the command options. It also introduces two
new tablegen backends: one for the property definitions and one for
their corresponding enums.

It might be worth mentioning that I generated most of the tablegen
definitions from the existing property definitions, by adding a dump
method to the struct. This seems both more efficient and less error
prone that copying everything over by hand. Only Enum properties needed
manual fixup for the EnumValues and DefaultEnumValue fields.

Differential revision: https://reviews.llvm.org/D65185

llvm-svn: 367058
2019-07-25 21:36:37 +00:00
Antonio Afonso 9294c87282 [LLDB] Find debugserver in Command Line Tools as well
Summary:
This might be an edge case in regular use but if you're shipping an lldb version with no debugserver lldb will try to use the System one.
However, lldb only knows how to find the Xcode one and not the Command Line Tools one. This diff fixes that.

We try to find debugserver with `PlatformDarwin::LocateExecutable("debugserver")`, we call `xcode-select -p` to get the path and then assume this path is of Xcode.

The changes I did are:
* Change `PlatformDarwin::LocateExecutable` to also add the Command Line Tools directory to the list of paths to search for debugserver.
* Created a new function to find the Command Line Tools directory named `GetCommandLineToolsLibraryPath`.
* Refactored the code that calls `xcode-select -p` into its own function `GetXcodeSelectPath()`. There were 2 identical pieces of code for this so I reduced it to one and used this function everywhere instead.
* I also changed `PlatformDarwin::GetSDKDirectoryForModules` to use the `SDKs` directory that exists in the Command Line Tools installation.

I'm not sure how to create tests for this. PlatformDarwinTest is really limited and I couldn't find how to mock Filesystem::Instance() so I could create a virtual file system.

Reviewers: clayborg, JDevlieghere

Reviewed By: clayborg, JDevlieghere

Subscribers: jasonmolenda, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D65171

llvm-svn: 367052
2019-07-25 20:53:00 +00:00
Michal Gorny e1c159e86a [lldb] [Process/NetBSD] Report stopped process on SIGSTOP
Mark the process as stopped when SIGSTOP arrives.  This is necessary
for lldb-server to generate correct response to 'process interrupt',
and therefore to prevent the whole stack crashing when process
is stopped.

Thanks to Pavel Labath for the tip.

Differential Revision: https://reviews.llvm.org/D65289

llvm-svn: 367047
2019-07-25 20:27:40 +00:00
Antonio Afonso d668260f1a Correctly use GetLoadedModuleList to take advantage of libraries-svr4
Summary:
Here's a replacement for D62504. I thought I could use LoadModules to implement this but in reality I can't because there are at few issues with it:
* The LoadModules assumes that the list returned by GetLoadedModuleList is comprehensive in the sense that reflects all the mapped segments, however, this is not true, for instance VDSO entry is not there since it's loaded manually by LoadVDSO using GetMemoryRegionInfo and it doesn't represent a specific shared object in disk. Because of this LoadModules will unload the VDSO module.
* The loader (interpreter) module might have also been loaded using GetMemoryRegionInfo, this is true when we launch the process and the rendezvous structure is not yet available (done through LoadInterpreterModule()). The problem here is that this entry will point to the same file name as the one found in /proc/pid/maps, however, when we read the same module from the r_debug.link_map structure it might be under a different name. This is true at least on CentOS where the loader is a symlink. Because of this LoadModules will unload and load the module in a way where the rendezvous breakpoint is unresolved but not resolved again (because we add the new module first and remove the old one after).

The symlink issue might be fixable by first unloading the old and loading the news (but sounds super brittle), however, I'm not sure how to fix the VDSO issue.
Since I can't trust it I'm just going to use GetLoadedModuleList directly with the same logic that we use today for when we read the linked list in lldb. The only safe thing to do here is to only calculate differences between different snapshots of the svr4 packet itself. This will also cut the dependency this plugin has from LoadModules.

I separated the 2 logics into 2 different functions (remote and not remote) because I don't like mixing 2 different logics in the same function with if/else's. Two different functions makes it easier to reason with I believe. However, I did abstract away the logic that decides if we should take a snapshot or add/remove modules so both functions could reuse it.

The other difference between the two is that on the UpdateSOEntriesFromRemote I take the snapshot only once when state = Consistent because I didn't find a good reason to always update that, as we already got the list from state = Add | Remove. I probably should use the same logic on UpdateSOEntries though I don't see a reason not to since it's really using the same data, just read in different places. Any thoughts here?

It might also be worthwhile to add a test to make sure we don't unload modules that were not actually "unloaded" like the vdso. I haven't done this yet though.
This diff is also missing the option for svr4 like proposed in https://reviews.llvm.org/D62503#1564296, I'll start working on this but wanted to have this up first.

Reviewers: labath, jankratochvil, clayborg, xiaobai

Reviewed By: labath

Subscribers: srhines, JDevlieghere, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D64013

llvm-svn: 367020
2019-07-25 14:28:21 +00:00
Raphael Isemann ec67e73430 [lldb] Tablegenify expr/frame/log/register/memory
llvm-svn: 367009
2019-07-25 11:22:46 +00:00
Fangrui Song 2e959415d7 SymbolFile: Fix -Wunused-variable in -DLLVM_ENABLE_ASSERTIONS=off builds after D65089/r366791
llvm-svn: 367001
2019-07-25 09:56:45 +00:00