This recommits b15b1421, which reverted in was reverted in f51c47d98 due to
failures on apple systems. The problem was that the patch introduced a race
where the debug server could start the attach process before the first process
(which isn't supposed to be attached to) was set up. This caused us to attach
to the wrong process.
The new version introduces additional synchronization to ensure that does not
happen.
Original commit message was:
As the documentation states, using this is not safe in multithreaded
programs, and I have traced it to a rare deadlock in some of the tests.
The reason this was introduced was to be able to attach to a program
from the very first instruction, where our usual mechanism of
synchronization -- waiting for a file to appear -- does not work.
However, this is only needed for a single test
(TestGdbRemoteAttachWait) so instead of doing this everywhere, I create
a bespoke solution for that single test. The solution basically
consists of outsourcing the preexec_fn code to a separate (and
single-threaded) shim process, which enables attaching and then executes
the real program.
This pattern could be generalized in case we needed to use it for other
tests, but I suspect that we will not be having many tests like this.
This effectively reverts commit
a997a1d7fbe229433fb458bb0035b32424ecf3bd.
As the documentation states, using this is not safe in multithreaded
programs, and I have traced it to a rare deadlock in some of the tests.
The reason this was introduced was to be able to attach to a program
from the very first instruction, where our usual mechanism of
synchronization -- waiting for a file to appear -- does not work.
However, this is only needed for a single test
(TestGdbRemoteAttachWait) so instead of doing this everywhere, I create
a bespoke solution for that single test. The solution basically
consists of outsourcing the preexec_fn code to a separate (and
single-threaded) shim process, which enables attaching and then executes
the real program.
This pattern could be generalized in case we needed to use it for other
tests, but I suspect that we will not be having many tests like this.
This effectively reverts commit
a997a1d7fbe229433fb458bb0035b32424ecf3bd.
Eliminate boilerplate of having each test manually assign to `mydir` by calling
`compute_mydir` in lldbtest.py.
Differential Revision: https://reviews.llvm.org/D128077
Add a function to make it easier to debug a test failure caused by an
unexpected state.
Currently, tests are using assertEqual which results in a cryptic error
message: "AssertionError: 5 != 10". Even when a test provides a message
to make it clear why a particular state is expected, you still have to
figure out which of the two was the expected state, and what the other
value corresponds to.
We have a function in lldbutil that helps you convert the state number
into a user readable string. This patch adds a wrapper around
assertEqual specifically for comparing states and reporting better error
messages.
The aforementioned error message now looks like this: "AssertionError:
stopped (5) != exited (10)". If the user provided a message, that
continues to get printed as well.
Differential revision: https://reviews.llvm.org/D127355
This patch adds a minor fix in lldbtest.py TestBase.generateSource
function. Generated Python source with directory paths was not being
escaped properly. This fix makes sure we treat dir path as raw string.
distutils is deprecated and shutil.which is the suggested
replacement for this function.
https://peps.python.org/pep-0632/#migration-advicehttps://docs.python.org/3/library/shutil.html#shutil.which
It was added in Python3.3 but given that we're already using
shutil.which elsewhere I think this is ok/no worse than before.
We do have our own find_executable in lldb/test/Shell/helper/build.py
but I'd rather leave that as is for now. Also we have our own versions
of which() but again, a change for another time.
This work is part of #54337.
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D124601
Add `IsAggregateType` to the SB API.
I'd like to use this from tests, and there are numerous other `Is<X>Type`
predicates on `SBType`.
Differential Revision: https://reviews.llvm.org/D121252
The race is between these two pieces of code that are executed in two separate
lldb-vscode threads (the first is in the main thread and another is in the
event-handling thread):
```
// lldb-vscode.cpp
g_vsc.debugger.SetAsync(false);
g_vsc.target.Launch(launch_info, error);
g_vsc.debugger.SetAsync(true);
```
```
// Target.cpp
bool old_async = debugger.GetAsyncExecution();
debugger.SetAsyncExecution(true);
debugger.GetCommandInterpreter().HandleCommands(GetCommands(), exc_ctx,
options, result);
debugger.SetAsyncExecution(old_async);
```
The sequence that leads to the bug is this one:
1. Main thread enables synchronous mode and launches the process.
2. When the process is launched, it generates the first stop event.
3. This stop event is catched by the event-handling thread and DoOnRemoval
is invoked.
4. Inside DoOnRemoval, this thread runs stop hooks. And before running stop
hooks, the current synchronization mode is stored into old_async (and
right now it is equal to "false").
5. The main thread finishes the launch and returns to lldb-vscode, the
synchronization mode is restored to asynchronous by lldb-vscode.
6. Event-handling thread finishes stop hooks processing and restores the
synchronization mode according to old_async (i.e. makes the mode synchronous)
7. And now the mode is synchronous while lldb-vscode expects it to be
asynchronous. Synchronous mode forbids the process to broadcast public stop
events, so, VS Code just hangs because lldb-vscode doesn't notify it about
stops.
So, this diff makes the target intercept the first stop event if the process is
launched in the synchronous mode, thus preventing stop hooks execution.
The bug is only present on Windows because other platforms already
intercept this event using their own hijacking listeners.
So, this diff also fixes some problems with lldb-vscode tests on Windows to make
it possible to run the related test. Other tests still can't be enabled because
the debugged program prints something into stdout and LLDB can't intercept this
output and redirect it to lldb-vscode properly.
Reviewed By: jingham
Differential Revision: https://reviews.llvm.org/D119548
It was being used only in some very old tests (which pass even without
it) and its implementation is highly questionable.
These days we have different mechanisms for requesting a build with a
particular kind of c++ library (USE_LIB(STD)CPP in the makefile).
This is an updated version of the https://reviews.llvm.org/D113789 patch with the following changes:
- We no longer modify modification times of the cache files
- Use LLVM caching and cache pruning instead of making a new cache mechanism (See DataFileCache.h/.cpp)
- Add signature to start of each file since we are not using modification times so we can tell when caches are stale and remove and re-create the cache file as files are changed
- Add settings to control the cache size, disk percentage and expiration in days to keep cache size under control
This patch enables symbol tables to be cached in the LLDB index cache directory. All cache files are in a single directory and the files use unique names to ensure that files from the same path will re-use the same file as files get modified. This means as files change, their cache files will be deleted and updated. The modification time of each of the cache files is not modified so that access based pruning of the cache can be implemented.
The symbol table cache files start with a signature that uniquely identifies a file on disk and contains one or more of the following items:
- object file UUID if available
- object file mod time if available
- object name for BSD archive .o files that are in .a files if available
If none of these signature items are available, then the file will not be cached. This keeps temporary object files from expressions from being cached.
When the cache files are loaded on subsequent debug sessions, the signature is compare and if the file has been modified (uuid changes, mod time changes, or object file mod time changes) then the cache file is deleted and re-created.
Module caching must be enabled by the user before this can be used:
symbols.enable-lldb-index-cache (boolean) = false
(lldb) settings set symbols.enable-lldb-index-cache true
There is also a setting that allows the user to specify a module cache directory that defaults to a directory that defaults to being next to the symbols.clang-modules-cache-path directory in a temp directory:
(lldb) settings show symbols.lldb-index-cache-path
/var/folders/9p/472sr0c55l9b20x2zg36b91h0000gn/C/lldb/IndexCache
If this setting is enabled, the finalized symbol tables will be serialized and saved to disc so they can be quickly loaded next time you debug.
Each module can cache one or more files in the index cache directory. The cache file names must be unique to a file on disk and its architecture and object name for .o files in BSD archives. This allows universal mach-o files to support caching multuple architectures in the same module cache directory. Making the file based on the this info allows this cache file to be deleted and replaced when the file gets updated on disk. This keeps the cache from growing over time during the compile/edit/debug cycle and prevents out of space issues.
If the cache is enabled, the symbol table will be loaded from the cache the next time you debug if the module has not changed.
The cache also has settings to control the size of the cache on disk. Each time LLDB starts up with the index cache enable, the cache will be pruned to ensure it stays within the user defined settings:
(lldb) settings set symbols.lldb-index-cache-expiration-days <days>
A value of zero will disable cache files from expiring when the cache is pruned. The default value is 7 currently.
(lldb) settings set symbols.lldb-index-cache-max-byte-size <size>
A value of zero will disable pruning based on a total byte size. The default value is zero currently.
(lldb) settings set symbols.lldb-index-cache-max-percent <percentage-of-disk-space>
A value of 100 will allow the disc to be filled to the max, a value of zero will disable percentage pruning. The default value is zero.
Reviewed By: labath, wallace
Differential Revision: https://reviews.llvm.org/D115324
Introduce a FreeBSDKernel plugin that provides the ability to read
FreeBSD kernel core dumps. The plugin utilizes libfbsdvmcore to provide
support for both "full memory dump" and minidump formats across variety
of architectures supported by FreeBSD. It provides the ability to read
kernel memory, as well as the crashed thread status with registers
on arm64, i386 and x86_64.
Differential Revision: https://reviews.llvm.org/D114911
Introduce a FreeBSDKernel plugin that provides the ability to read
FreeBSD kernel core dumps. The plugin utilizes libfbsdvmcore to provide
support for both "full memory dump" and minidump formats across variety
of architectures supported by FreeBSD. It provides the ability to read
kernel memory, as well as the crashed thread status with registers
on arm64, i386 and x86_64.
Differential Revision: https://reviews.llvm.org/D114911
This patch fixes an amusing bug where a Platform::Kill operation would
happily terminate a proces on a completely different platform, as long
as they have the same process ID. This was due to the fact that the
implementation was iterating through all known (debugged) processes in
order terminate them directly.
This patch just deletes that logic, and makes everything go through the
OS process termination APIs. While it would be possible to fix the logic
to check for a platform match, it seemed to me that the implementation
was being too smart for its own good -- accessing random Process
objects without knowing anything about their state is risky at best.
Going through the os ensures we avoid any races.
I also "upgrade" the termination signal to a SIGKILL to ensure the
process really dies after this operation.
Differential Revision: https://reviews.llvm.org/D113184
join is only available since python-3.8, but the all the interesting
magic happens in shlex.quote, which has been around since 3.3.
Use shlex.quote, and instead provide a home-grown helper function to
handle the joining.
Differential Revision: https://reviews.llvm.org/D112802
Running tests with -t prints all lldb commands being run. It makes sense
to print all the build commands as well.
Differential Revision: https://reviews.llvm.org/D112212
When targeting iOS, the default dwarf version is 2 and not 4. Currently,
the test suite does not pick up on that because it invokes the test
compiler without a target triple. This patch fixes that and now
correctly skips tests that have a dwarf version specified in a skipIf
decorator.
rdar://84530477
Differential revision: https://reviews.llvm.org/D112325
This patch is a smaller version of a previous patch https://reviews.llvm.org/D110804.
This patch modifies the output of "statistics dump" to be able to get stats from the current target. It adds 3 new stats as well. The output of "statistics dump" is now emitted as JSON so that it can be used to track performance and statistics and the output could be used to populate a database that tracks performance. Sample output looks like:
(lldb) statistics dump
{
"expressionEvaluation": {
"failures": 0,
"successes": 0
},
"firstStopTime": 0.34164492800000001,
"frameVariable": {
"failures": 0,
"successes": 0
},
"launchOrAttachTime": 0.31969605400000001,
"targetCreateTime": 0.0040863039999999998
}
The top level keys are:
"expressionEvaluation" which replaces the previous stats that were emitted as plain text. This dictionary contains the success and fail counts.
"frameVariable" which replaces the previous stats for "frame variable" that were emitted as plain text. This dictionary contains the success and fail counts.
"targetCreateTime" contains the number of seconds it took to create the target and load dependent libraries (if they were enabled) and also will contain symbol preloading times if that setting is enabled.
"launchOrAttachTime" is the time it takes from when the launch/attach is initiated to when the first private stop occurs.
"firstStopTime" is the time in seconds that it takes to stop at the first stop that is presented to the user via the LLDB interface. This value will only have meaning if you set a known breakpoint or stop location in your code that you want to measure as a performance test.
This diff is also meant as a place to discuess what we want out of the "statistics dump" command before adding more funcionality. It is also meant to clean up the previous code that was storting statistics in a vector of numbers within the lldb_private::Target class.
Differential Revision: https://reviews.llvm.org/D111686
None of the commands we run really rely on shell features. Running them
with shell=False, simplifies the code as there is no need for elaborate
quoting.
Differential Revision: https://reviews.llvm.org/D111990
We had two sets of build<flavour> methods, whose bodies were largely
identical. This makes any kind of modification in their vicinity
repetitive and error-prone.
Replace each set with a single method taking an optional debug_info
parameter.
Differential Revision: https://reviews.llvm.org/D111989
We only had that ability for regular debugger launches. This meant that
it was not possible to use the normal dlopen patterns in attach tests.
This fixes that.
This patch adds a helper function to test target architecture is
AArch64 or not. This also tightens isAArch64* helpers by adding an
extra architecture check.
Reviewed By: DavidSpickett
Differential Revision: https://reviews.llvm.org/D105483
At the moment nearly every test calls something similar to
`self.dbg.CreateTarget(self.getBuildArtifact("a.out"))` and them sometimes
checks if the created target is actually valid with something like
`self.assertTrue(target.IsValid(), "some useless text")`.
Beside being really verbose the error messages generated by this pattern are
always just indicating that the target failed to be created but now why.
This patch introduces a helper function `createTestTarget` to our Test class
that creates the target with the much more verbose `CreateTarget` overload that
gives us back an SBError (with a fancy error). If the target couldn't be created
the function prints out the SBError that LLDB returned and asserts for us. It
also defaults to the "a.out" build artifact path that nearly all tests are using
to avoid to hardcode "a.out" in every test.
I converted a bunch of tests to the new function but I'll do the rest of the
test suite as follow ups.
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D102771
AArch64 kernel builds default to having /smaps and
the "VmFlags" line was added in 3.8. Long before MTE
was supported.
So we can assume that if you're AArch64 with MTE,
you can run this test.
The previous method of checking had a race condition
where the process we read smaps for, could finish before
we get to read the file.
I explored some alternatives but in the end I think
it's fine to just assume we have what we need.
Reviewed By: omjavaid
Differential Revision: https://reviews.llvm.org/D100493
Use a with block for reading the cpuinfo file.
When loading the file fails (or we're not on Linux)
return an empty string. Since all the callers are
going to do "x in self.getCPUInfo()".
Reviewed By: omjavaid
Differential Revision: https://reviews.llvm.org/D99729
This patch adds a test case to test AArch64 dynamic register sets.
This tests for the availability of certain register sets and query
their registers accordingly.
Reviewed By: labath, DavidSpickett
Differential Revision: https://reviews.llvm.org/D96463
Linux systems can be configured (and most of them are configured that
way) to disable attaching to unrelated processes, /unless/ those
processes explicitly allow that.
Our test inferiors do that by explicitly calling prctl(PR_SET_PTRACER,
PR_SET_PTRACER_ANY) (a.k.a., lldb_enable_attach). This requires
additional synchronization to ensure that the test does not attempt
attach before that statement is executed.
This is working fine (albeit cumbersome) for most tests but
TestGdbRemoteAttachWait is special in that it wants to start the
inferior _after_ issuing the attach request. This means that the usual
synchronization method does not work.
This patch introduces a different solution -- enable attaching in the
test harness, before the process is launched. Besides fixing this
problem, this is also better because it avoids the need to add special
code to each attach test (which is a common error).
One gotcha here is that it won't work for remote test suites, as we
don't control launching there. However, we could add a similar option to
lldb-platform, or require that lldb-platform itself is started with
attaching enabled. At that point we could delete all lldb_enable_attach
logic.
The test was marked as remote-only, which means it was run ~never, and
accumulated various problems. This commit modifies the test to run
locally and includes a couple of other fixes necessary to make it run:
- moves the "invoke" method into the "Base" test class
- adds []'s around the IP address in a couple more places to make things
work with IPv6
The test is now marked as skipped when running the remote test suite. It
would be possible to make it run both locally and remotely, but this
would require writing a lot special logic for the remote case, and that
is not worth it.
lldb-server tests are a very special subclass of "api" tests. As they
communicate with lldb-server directly, they don't actually need most of
facilities provided by our TestBase class. In particular, they don't
need the ability to fork debug info flavours of tests (but they could
use debug server flavours).
This makes them inherit from "Base" instead. This avoids the need to
explicitly mark these tests as NO_DEBUG_INFO_TEST_CASE. Two additional
necessary tweaks were:
- move run_platform_command to the base (Base) class. This is used in
one test, and can be generally useful when running tests remotely.
- add a "build" method, forwarding to buildDefault. This is to avoid
updating each test case to use buildDefault (also, "build" sounds
better). It might be interesting to refactor the (Test)Base classes so
that all debug info flavour handling happens in TestBase, and the Base
class provides a simple build method automatically.
Kill (rather than detach) form the inferior if debugserver loses its
connection to lldb to prevent zombie processes.
Differential revision: https://reviews.llvm.org/D92908
Test runs log some of their output to files inside the LLDB session dir. This
session dir is shared between all tests, so all the tests have to make sure they
choose a unique file name inside that directory. We currently choose by default
`<test-class-name>-<test-method-name>` as the log file name. However, that means
that if not every test class in the test suite has a unique class name, then we
end up with a race condition as two tests will try to write to the same log
file.
I already tried in D83767 changing the format to use the test file basename
instead (which we already require to be unique for some other functionality),
but it seems the code for getting the basename didn't work on Windows.
This patch instead just changes that dotest stores the log files in the build
directory for the current test. We know that directory is unique for this test,
so no need to generate some unique file name now. Also removes all the
environment vars and parameters related to the now unused session dir.
The new log paths now look like this for a failure in 'TestCppOperators`:
```
./lldb-test-build.noindex/lang/cpp/operators/TestCppOperators.test_dwarf/Failure.log
./lldb-test-build.noindex/lang/cpp/operators/TestCppOperators.test_dsym/Failure.log
./lldb-test-build.noindex/lang/cpp/operators/TestCppOperators.test_gmodules/Failure.log
```
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D92498
This extends the "memory region" command to
show tagged regions on AArch64 Linux when the MTE
extension is enabled.
(lldb) memory region the_page
[0x0000fffff7ff8000-0x0000fffff7ff9000) rw-
memory tagging: enabled
This is done by adding an optional "flags" field to
the qMemoryRegion packet. The only supported flag is
"mt" but this can be extended.
This "mt" flag is read from /proc/{pid}/smaps on Linux,
other platforms will leave out the "flags" field.
Where this "mt" flag is received "memory region" will
show that it is enabled. If it is not or the target
doesn't support memory tagging, the line is not shown.
(since majority of the time tagging will not be enabled)
Testing is added for the existing /proc/{pid}/maps
parsing and the new smaps parsing.
Minidump parsing has been updated where needed,
though it only uses maps not smaps.
Target specific tests can be run with QEMU and I have
added MTE flags to the existing helper scripts.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D87442
This adds `expect_var_path` to test variable paths so we no longer have to
use `frame var` and find substrs in the command output. The behaviour
is identical with `expect_expr` (and it also uses the same checking backend),
but it instead calls `GetValueForVariablePath` to evaluate the string as a variable
path.
Also rewrites a few of the tests that previously used `frame variable` to use
`expect_var_path`.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D90450
Depends on D89408.
This diff finally implements trace decoding!
The current interface is
$ trace load /path/to/trace/session/file.json
$ thread trace dump instructions
thread #1: tid = 3842849, total instructions = 22
[ 0] 0x40052d
[ 1] 0x40052d
...
[19] 0x400521
$ # simply enter, which is a repeat command
[20] 0x40052d
[21] 0x400529
...
This doesn't do any disassembly, which will be done in the next diff.
Changes:
- Added an IntelPTDecoder class, that is a wrapper for libipt, which is the actual library that performs the decoding.
- Added TraceThreadDecoder class that decodes traces and memoizes the result to avoid repeating the decoding step.
- Added a DecodedThread class, which represents the output from decoding and that for the time being only stores the list of reconstructed instructions. Later it'll contain the function call hierarchy, which will enable reconstructing backtraces.
- Added basic APIs for accessing the trace in Trace.h:
- GetInstructionCount, which counts the number of instructions traced for a given thread
- IsTraceFailed, which returns an Error if decoding a thread failed
- ForEachInstruction, which iterates on the instructions traced for a given thread, concealing the internal storage of threads, as plug-ins can decide to generate the instructions on the fly or to store them all in a vector, like I do.
- DumpTraceInstructions was updated to print the instructions or show an error message if decoding was impossible.
- Tests included
Differential Revision: https://reviews.llvm.org/D89283
In D89056 the default value for architecture was moved to `build` so that
all called functions see the same architecture value. It seems there are a
few functions that call buildDefault directly (and not via build), so
on some test configurations that set a custom arch value the architecture
value is no longer available.
This just adds the architecture code from build to buildDefault to get
the bots green again while I'm looking for a better solution.
This originally broke the TestQuoting which explicitly called buildDefault
instead of calling build() and marking the test as no_debug_info_test.
TestQuoting has been rewritten by now and is using `build`, so this should now
pass on all platforms.
Original summary:
The Darwin builder currently assumes in `getArchCFlags` that the passed `arch`
value is an actual string it can string.join with vendor/os/version/env strings:
```
triple = '-'.join([arch, vendor, os, version, env])
```
However this is not true for most tests as we just pass down the `arch=None`
default value from `TestBase.build`. This causes that if we actually end up in
this function we just error out when concatenating `None` with the other actual
strings of vendor/os/version/env. What we should do instead is check that if
there is no test-specific architecture that we fall back to the configuration's
architecture value.
It seems we already worked around this in `builder.getArchSpec` by explicitly
falling back to the architecture specified in the configuration.
This patch just moves this fallback logic to the top `build` function so that it
affects all functions called from `TestBase.build`.
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D89056
The intention is not to allow stop-hook commands to query the
user, so this is correct. It also works around a deadlock in
switching to the Python Session to execute python based commands
in the stop hook when the Debugger stdin is backed by a FILE *.
Differential Revision: https://reviews.llvm.org/D90332
