Right now we have one large AST for all types in LLDB. All ODR violations in
types we reconstruct are resolved by just letting the ASTImporter handle the
conflicts (either by merging types or somehow trying to introduce a duplicated
declaration in the AST). This works ok for the normal types we build from debug
information as most of them are just simple CXXRecordDecls or empty template
declarations.
However, with a loaded `std` C++ module we have alternative versions of pretty
much all declarations in the `std` namespace that are much more fleshed out than
the debug information declarations. They have all the information that is lost
when converting to DWARF, such as default arguments, template default arguments,
the actual uninstantiated template declarations and so on.
When we merge these C++ module types into the big scratch AST (that might
already contain debug information types) we give the ASTImporter the tricky task
of somehow creating a consistent AST out of all these declarations. Usually this
ends in a messy AST that contains a mostly broken mix of both module and debug
info declarations. The ASTImporter in LLDB is also importing types with the
MinimalImport setting, which usually means the only information we have when
merging two types is often just the name of the declaration and the information
that it contains some child declarations. This makes it pretty much impossible
to even implement a better merging logic (as the names of C++ module
declarations and debug info declarations are identical).
This patch works around this whole merging problem by separating C++ module
types from debug information types. This is done by splitting up the single
scratch AST into two: One default AST for debug information and a dedicated AST
for C++ module types.
The C++ module AST is implemented as a 'specialised AST' that lives within the
default ScratchTypeSystemClang. When we select the scratch AST we can explicitly
request that we want such a isolated sub-AST of the scratch AST. I kept the
infrastructure more general as we probably can use the same mechanism for other
features that introduce conflicting types (such as programs that are compiled
with a custom -wchar-size= option).
There are just two places where we explicitly have request the C++ module AST:
When we export persistent declarations (`$mytype`) and when we create our
persistent result variable (`$0`, `$1`, ...). There are a few formatters that
were previously assuming that there is only one scratch AST which I cleaned up
in a preparation revision here (D92757).
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D92759
Prevent lldb from crashing when multiple threads are concurrently
accessing the SB API with reproducer capture enabled.
The API instrumentation records both the input arguments and the return
value, but it cannot block for the duration of the API call. Therefore
we introduce a sequence number that allows to to correlate the function
with its result and add locking to ensure those two parts are emitted
atomically.
Using the sequence number, we can detect situations where the return
value does not succeed the function call, in which case we print an
error saying that concurrency is not (currently) supported. In the
future we might attempt to be smarter and read ahead until we've found
the return value matching the current call.
Differential revision: https://reviews.llvm.org/D92820
Several data formatters assume their types are in the Target's scratch AST and
build new types from that scratch AST instance. However, types from different
ASTs shouldn't be mixed, so this (unchecked) assumption may lead to problems if
we ever have more than one scratch AST or someone somehow invokes data
formatters on a type that are not in the scratch AST.
Instead we can use in all the formatters just the TypeSystem of the type we're
formatting. That's much simpler and avoids all the headache of finding the right
TypeSystem that matches the one of the formatted type.
Right now LLDB only has one scratch TypeSystemClang instance and we format only
types that are in the scratch AST, so this doesn't change anything in the
current way LLDB works. The intention here is to allow follow up refactorings
that introduce multiple scratch ASTs with the same Target.
Differential Revision: https://reviews.llvm.org/D92757
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.
LLDB is supposed to ask the Clang Driver what the default module cache path is
and then use that value as the default for the
`symbols.clang-modules-cache-path` setting. However, we use the property type
`String` to change `symbols.clang-modules-cache-path` even though the type of
that setting is `FileSpec`, so the setter will simply do nothing and return
`false`. We also don't check the return value of the setter, so this whole code
ends up not doing anything at all.
This changes the setter to use the correct property type and adds an assert that
we actually successfully set the default path. Also adds a test that checks that
the default value for this setting is never unset/empty path as this would
effectively disable the import-std-module feature from working by default.
Reviewed By: JDevlieghere, shafik
Differential Revision: https://reviews.llvm.org/D92772
By now LLDB can import the 'std' C++ module to improve expression evaluation,
but there are still a few problems to solve before we can do this by default.
One is that importing the C++ module is slightly slower than normal expression
evaluation (mostly because the disk access and loading the initial lookup data
is quite slow in comparison to the barebone Clang setup the rest of the LLDB
expression evaluator is usually doing). Another problem is that some complicated
types in the standard library aren't fully supported yet by the ASTImporter, so
we end up types that fail to import (which usually appears to the user as if the
type is empty or there is just no result variable).
To still allow people to adopt this mode in their daily debugging, this patch
adds a setting that allows LLDB to automatically retry failed expression with a
loaded C++ module. All success expressions will behave exactly as they would do
before this patch. Failed expressions get a another parse attempt if we find a
usable C++ module in the current execution context. This way we shouldn't have
any performance/parsing regressions in normal debugging workflows, while the
debugging workflows involving STL containers benefit from the C++ module type
info.
This setting is off by default for now with the intention to enable it by
default on macOS soon-ish.
The implementation is mostly just extracting the existing parse logic into its
own function and then calling the parse function again if the first evaluation
failed and we have a C++ module to retry the parsing with.
Reviewed By: shafik, JDevlieghere, aprantl
Differential Revision: https://reviews.llvm.org/D92784
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
When the architecture from the returned plist differs from the
architecture lldb will pick when loading the binary file, lldb will
reject the binary as not matching. We are working with UUID's in
this case, so an architecture is not disambiguating anything; it
just opens this possibility for failing to load the specified binary.
Stop reading the architecture from the plist.
<rdar://problem/71612561>
Differential revision: https://reviews.llvm.org/D92692
The reproducers currently use a static variable to track the API
boundary. This is obviously incorrect when the SB API is used
concurrently. While I do not plan to support that use-case (right now),
I do want to avoid us crashing. As a first step, correctly track API
boundaries across multiple threads.
Before this patch SB API calls made by the embedded script interpreter
would be considered "behind the API boundary" and correctly ignored.
After this patch, we need to tell the reproducers to ignore the
scripting thread as a "private thread".
Differential revision: https://reviews.llvm.org/D92811
TestLldbGdbServer.py testcases are timing out on LLDB/AArch64 Linux
buildbot since recent changes. I am temporarily increasing
DEFAULT_TIMEOUT to 20 seconds to see impact.
LLDB is ignoring compilation errors for one-line breakpoint scripts.
This patch fixes the issues and now the error message of the
ScriptInterpreter is shown to the user.
I had to remove a new-line character for the Lua interpreter since it
was duplicated.
Differential Revision: https://reviews.llvm.org/D92729
The test is skipped/xfailing on all platforms, so it seems that the API
got out of sync. Fix that so it returns to a 'proper' failure
on FreeBSD.
Differential Revision: https://reviews.llvm.org/D92746
Copy the Linux implementation of GetLoadedModuleFileSpec()
and GetFileLoadAddress() into NativeProcessFreeBSD. This does not seem
to change anything at the moment but reducing the differences between
the plugins should help us in the long term.
Differential Revision: https://reviews.llvm.org/D92314
Explicitly consider the libraries reported on the initial eTakeSnapshot
action added, through adding them to the added soentry list
in DYLDRendezvous::SaveSOEntriesFromRemote(). This is necessary
on FreeBSD since the dynamic loader issues only a single 'consistent'
state rendezvous breakpoint hit for all the libraries present
in DT_NEEDED (while Linux issues an added-consistent event pair).
Reenable memory maps on FreeBSD since this fixed the issue triggered
by them.
Differential Revision: https://reviews.llvm.org/D92187
Force gdb-remote plugin when attaching using the derivatives
of PlatformPOSIX class. This is consistent with the behavior
for launching processes (via DebugProcess() method) and guarantees
consistent plugin choice on FreeBSD.
Differential Revision: https://reviews.llvm.org/D92667
Now that the class does not use a thread, the name is no longer
appropriate. Rename the class to "Server" and make it a long-lived
object (instead of recreating it for every expect_gdbremote_sequence
call). The idea is to make this class a wrapper for all communication
with debug/lldb-server. This will enable some additional cleanups as we
had some duplication between socket_pump non-pump code paths.
Also squeeze in some small improvements:
- use python-level timeouts on sockets instead of the manual select
calls
- use byte arrays instead of strings when working with raw packets
Use the newly added spawnattr API, posix_spawnattr_setarchpref_np, to
select a slice preferences per cpu and subcpu types, instead of just cpu
with posix_spawnattr_setarchpref_np.
rdar://16094957
Differential revision: https://reviews.llvm.org/D92712
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
We keep referring to the single object created by this class as
'scratch AST/Context/TypeSystem' so at this point we might as well rename the
class. It's also not involved at all in expression evaluation, so the
'ForExpressions' prefix is a bit misleading.
Use the cpu subtype enum values from llvm::MachO in the ArchSpec MachO
table. As I'm already cluttering the history, restore the table's
formatting to its original glory.
Differential revision: https://reviews.llvm.org/D92601
We found out that we have clients relying on the old signature of the
Symbolicator initializer. Make the signature compatible again and
provide a factory method to initialize the class correctly based on
whether you have a target or want the symbolicator to create one for
you.
Differential revision: D92601
Make sure we recognize cpu sub-type 2 as arm64. In reality it's arm64e,
but we don't have the triple for that. Without this patch, we fall back
to unknown-apple-macosx- for the default architecture, which breaks
things like running expressions without a target.
Differential revision: https://reviews.llvm.org/D92603
Extract remote debugging logic from PlatformMacOSX and move it into
PlatformRemoteMacOSX so it can benefit from all the logic necessary for
remote debugging.
Until now, remote macOS debugging was treated almost identical to local
macOS debugging. By moving in into its own class, we can have it inherit
from PlatformRemoteDarwinDevice and all the functionality it provides,
such as looking at the correct DeviceSupport directory.
rdar://68167374
Differential revision: https://reviews.llvm.org/D92452
Jonas Devlieghere