Re-lands 04aa943be8ed5c03092e2a90112ac638360ec253 with modifications
to fix tests.
I originally reverted this because it caused a test to fail on Linux.
The problem was that I inverted a condition on accident.
There are many situations where we'll iterate over a SymbolContextList
with the pattern:
```
SymbolContextList sc_list;
// Fill in sc_list here
for (auto i = 0; i < sc_list.GetSize(); i++) {
SymbolContext sc;
sc_list.GetSymbolAtContext(i, sc);
// Do work with sc
}
```
Adding an iterator to iterate over the instances directly means we don't
have to do bounds checking or create a copy of every element of the
SymbolContextList.
Differential Revision: https://reviews.llvm.org/D149900
The qHostInfo packet in the gdb-remote communication protocol specifies
that distribution_id can be set, so lldb handles that. But we store that
in the ArchSpec representing the "Host" platform (whatever platform the
debug server is running on). This field is otherwise unused in ArchSpec,
so it would be a lot easier if we stored that information at the
gdb-remote communication layer.
Sidenote: The distribution_id field is currently unused but I did not
want to remove it in case some folks found it useful (e.g. in downstream
forks).
Differential Revision: https://reviews.llvm.org/D149697
Instead of taking a `const std::string &` we can take an
`llvm::StringRef`. The motivation for this change is that many of the
callers of `ParseJSON` end up creating a temporary `std::string` from an existing
`StringRef` or `const char *` in order to satisfy the API. There's no
reason we need to do this.
Differential Revision: https://reviews.llvm.org/D148579
lldb was originally designed to get the watchpoint exception behavior
from the gdb remote serial protocol stub -- exceptions are either
received before the instruction executes, or after the instruction
has executed. This behavior was reported via two lldb extensions
to gdb RSP, so generic remote stubs like gdbserver or a JTAG stub,
would not tell lldb which behavior was correct, and it would default
to "exceptions are received after the instruction has executed".
Two architectures hard coded their correct "exceptions before
instruction" behavior, to work around this issue.
Most architectures have a fixed behavior of watchpoint exceptions,
and we can center that information in lldb. We can allow a remote
stub to override the default behavior via our packet extensions
if it's needed on a specific target.
This patch also separates the fetching of the number of watchpoints
from whether exceptions are before/after the insn. Currently if
lldb couldn't fetch the number of watchpoints (not really needed), it
also wouldn't get when exceptions are received, and watchpoint
handling would fail. lldb doesn't actually use the number of
watchpoints for anything beyond printing it to the user.
Differential Revision: https://reviews.llvm.org/D143215
rdar://101426626
The dynamic linker on Darwin, dyld, can provide status of
the process state for a few significant points early on,
most importantly, when libSystem has been initialized and it
is safe to call functions behind the scenes. Pipe this
information up from debugserver to DynamicLoaderMacOS, for
the DynamicLoader::IsFullyInitialized() method, then have
Thread::SafeToCallFunctions use this information. Finally,
for the two utility functions in the AppleObjCRuntimeV2
LanguageRuntime plugin that I was fixing, call this method
before running our utility functions to collect the list of
objc classes registered in the runtime.
User expressions will still be allowed to run any time -
we assume the user knows what they are doing - but these
two additional utility functions that they are unaware of
will be limited by this state.
Differential Revision: https://reviews.llvm.org/D139054
rdar://102436092
can probably make function calls.
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated. The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.
This is part of an effort to migrate from llvm::Optional to
std::optional:
https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
A malformed qMemoryRegionInfo response can easily trigger an infinite
loop if regions end (base + size) wraps the address space. A
particularly interesting is the case where base+size=0, which a stub
could use to say that the rest of the memory space is unmapped, even
though lldb expects 0xff... in this case.
One could argue which behavior is more correct (technically, the
current behavior does not say anything about the last byte), but unless
we stop using 0xff... to mean "invalid address", that discussion is very
academic. This patch truncates address ranges which wraps the address
space, which handles the zero case as well as other kinds of malformed
packets.
Use our "rich error" facility to propagate error reported by the stub to
the user. lldb-server reports rich launch errors as of D133352.
To make this easier to implement, and reduce code duplication, I have
moved the vRun/A/qLaunchSuccess handling into a single
GDBRemoteCommunicationClient function.
Differential Revision: https://reviews.llvm.org/D134754
Complete support of the binary-addresses key in the qProcessInfo packet
in ProcessGDBRemote, for detecting if one of the binaries needs to be
handled by a Platform plugin, and can be used to set the Process'
DynamicLoader plugin and the Target's Platform plugin.
Implement this method in PlatformDarwinKernel to recognize a kernel
fileset at that address, find the actual kernel address in the
fileset, set DynamicLoaderDarwinKernel and PlatformDarwinKernel
in the Process/Target; register the kernel address with the dynamic
loader so it will be loaded later during attach.
This patch only addresses the live debug scenario with a gdb remote
serial protocol connection. I'll handle corefiles in a subsequent
patch that builds on this.
Differential Revision: https://reviews.llvm.org/D133534
rdar://98754861
Move the broadcasting support from GDBRemoteCommunication
to GDBRemoteClientBase since this is where it is actually used. Remove
GDBRemoteCommunication and subclass constructor arguments left over
after Communication cleanup.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D133427
Try to always send vCont packets and include the PID in them if running
multiprocess. This is necessary to ensure that with the upcoming full
multiprocess support always resumes the correct process without having
to resort to the legacy Hc packets.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D131758
Try to always send vCont packets and include the PID in them if running
multiprocess. This is necessary to ensure that with the upcoming full
multiprocess support always resumes the correct process without having
to resort to the legacy Hc packets.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D131758
Add support to Mach-O corefiles and to live gdb remote serial protocol
connections for the corefile/remote stub to provide a list of load
addresses of binaries that should be found & loaded by lldb, and nothing
else. lldb will try to parse the binary out of memory, and if it can
find a UUID, try to find a binary & its debug information based on the
UUID, falling back to using the memory image if it must.
A bit of code unification from three parts of lldb that were loading
individual binaries already, so there is a shared method in
DynamicLoader to handle all of the variations they were doing.
Re-landing this with a uuid_is_null() implementation added to
Utility/UuidCompatibility.h for non-Darwin systems.
Differential Revision: https://reviews.llvm.org/D130813
rdar://94249937
rdar://94249384
This reverts commit d8879fba8825b9799166ba0ea552d4027bfb8ad1.
Debian bot failure; I included <uuid/uuid.h> to get uuid_is_null() but
don't get it there. Will memcmp or whatever & recommit.
Add support to Mach-O corefiles and to live gdb remote serial protocol
connections for the corefile/remote stub to provide a list of load
addresses of binaries that should be found & loaded by lldb, and nothing
else. lldb will try to parse the binary out of memory, and if it can
find a UUID, try to find a binary & its debug information based on the
UUID, falling back to using the memory image if it must.
A bit of code unification from three parts of lldb that were loading
individual binaries already, so there is a shared method in
DynamicLoader to handle all of the variations they were doing.
Differential Revision: https://reviews.llvm.org/D130813
rdar://94249937
rdar://94249384
Refactor the code responsible for sending the "k" packet and move it
into GDBRemoteCommunicationClient::KillProcess() method. This is part
of refactoring to enable multiprocess support in the client,
and to support using the vKill packet instead.
As part of the refactoring, the following functional changes apply:
- Some redundant logging has been removed, as any failures are returned
via exit_string anyway.
- SetLastStopPacket() is no longer called. It is used only to populate
the thread list, and since the process has just exited and we're
terminating the process instance, there's really no reason to set it.
- On successful kill, exit_string is set to "killed", to clearly
indicate that the process has terminated on our request rather than
on its own.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D130340
- Add the logic that parses all cpu context switch traces and produces blocks of continuous executions, which will be later used to assign intel pt subtraces to threads and to identify gaps. This logic can also identify if the context switch trace is malformed.
- The continuous executions blocks are able to indicate when there were some contention issues when producing the context switch trace. See the inline comments for more information.
- Update the 'dump info' command to show information and stats related to the multicore decoding flow, including timing about context switch decoding.
- Add the logic to conver nanoseconds to TSCs.
- Fix a bug when returning the context switches. Now they data returned makes sense and even empty traces can be returned from lldb-server.
- Finish the necessary bits for loading and saving a multi-core trace bundle from disk.
- Change some size_t to uint64_t for compatibility with 32 bit systems.
Tested by saving a trace session of a program that sleeps 100 times, it was able to produce the following 'dump info' text:
```
(lldb) trace load /tmp/trace3/trace.json (lldb) thread trace dump info Trace technology: intel-pt
thread #1: tid = 4192415
Total number of instructions: 1
Memory usage:
Total approximate memory usage (excluding raw trace): 2.51 KiB
Average memory usage per instruction (excluding raw trace): 2573.00 bytes
Timing for this thread:
Timing for global tasks:
Context switch trace decoding: 0.00s
Events:
Number of instructions with events: 0
Number of individual events: 0
Multi-core decoding:
Total number of continuous executions found: 2499
Number of continuous executions for this thread: 102
Errors:
Number of TSC decoding errors: 0
```
Differential Revision: https://reviews.llvm.org/D126267
Currently, all data buffers are assumed to be writable. This is a
problem on macOS where it's not allowed to load unsigned binaries in
memory as writable. To be more precise, MAP_RESILIENT_CODESIGN and
MAP_RESILIENT_MEDIA need to be set for mapped (unsigned) binaries on our
platform.
Binaries are mapped through FileSystem::CreateDataBuffer which returns a
DataBufferLLVM. The latter is backed by a llvm::WritableMemoryBuffer
because every DataBuffer in LLDB is considered to be writable. In order
to use a read-only llvm::MemoryBuffer I had to split our abstraction
around it.
This patch distinguishes between a DataBuffer (read-only) and
WritableDataBuffer (read-write) and updates LLDB to use the appropriate
one.
rdar://74890607
Differential revision: https://reviews.llvm.org/D122856
Don't overwrite the host architecture (obtained from qHostInfo) with the
process info (obtained from qProcessInfo).
Differential revision: https://reviews.llvm.org/D121442
Most of our code was including Log.h even though that is not where the
"lldb" log channel is defined (Log.h defines the generic logging
infrastructure). This worked because Log.h included Logging.h, even
though it should.
After the recent refactor, it became impossible the two files include
each other in this direction (the opposite inclusion is needed), so this
patch removes the workaround that was put in place and cleans up all
files to include the right thing. It also renames the file to LLDBLog to
better reflect its purpose.
Add Thread::GetSiginfo() and SBThread::GetSiginfo() methods to retrieve
the siginfo value from server.
Differential Revision: https://reviews.llvm.org/D118055
Add Thread::GetSiginfo() and SBThread::GetSiginfo() methods to retrieve
the siginfo value from server.
Differential Revision: https://reviews.llvm.org/D118055
Support three new keys in the qProcessInfo response from the remote
gdb stub to handle the case of attaching to a core running some type
of standalone/firmware code and the stub knows the UUID and load
address-or-slide for the binary. There will be no proper DynamicLoader
plugin in this scenario, but we can try to locate and load the binary
into lldb at the correct offset.
Differential Revision: https://reviews.llvm.org/D116211
rdar://75191077
This code, added in rL197579 (Dec 2013) is supposed to work around what
was presumably a qemu bug, where it would send unsolicited stop-reply
packets after the initial connection.
At present, qemu does not exhibit such behavior. Also, the 10ms delay
introduced by this code is sufficient to mask bugs in other stubs, but
it is not sufficient to *reliably* mask those bugs. This resulted in
flakyness in one of our stubs, which was (incorrectly) sending a +
packet at the start of the connection, resulting in a small-but-annoying
number of dropped connections.
Differential Revision: https://reviews.llvm.org/D114529
GDB and LLDB use different signal models. GDB uses a predefined set
of signal codes, and maps platform's signos to them. On the other hand,
LLDB has historically simply passed native signos.
In order to improve compatibility between LLDB and gdbserver, the GDB
signal model should be used. However, GDB does not provide a mapping
for all existing signals on Linux and unsupported signals are passed
as 'unknown'. Limiting LLDB to this behavior could be considered
a regression.
To get the best of both worlds, use the LLDB signal model when talking
to lldb-server, and the GDB signal model otherwise. For this purpose,
new versions of lldb-server indicate "native-signals+" via qSupported.
At the same time, we also detect older versions of lldb-server
via QThreadSuffixSupported for backwards compatibility. If neither test
succeeds, we assume gdbserver or another implementation using GDB model.
Differential Revision: https://reviews.llvm.org/D108078
From the documentation:
A Twine is not intended for use directly and should not be stored, its
implementation relies on the ability to store pointers to temporary
stack objects which may be deallocated at the end of a statement.
Twines should only be used accepted as const references in arguments,
when an API wishes to accept possibly-concatenated strings.
rdar://84799118
Differential revision: https://reviews.llvm.org/D113314
Optimize the iterator comparison logic to compare Current.data()
pointers. Use std::tie for assignments from std::pair. Replace
the custom class with a function returning iterator_range.
Differential Revision: https://reviews.llvm.org/D110535