As specified in the docs,
1) raw_string_ostream is always unbuffered and
2) the underlying buffer may be used directly
( 65b13610a5226b84889b923bae884ba395ad084d for further reference )
* Don't call raw_string_ostream::flush(), which is essentially a no-op.
* Avoid unneeded calls to raw_string_ostream::str(), to avoid excess
indirection.
Emit signpost intervals for progress events so that when users report an
operation takes a long time, we can investigate the issue with
Instruments.app.
Print a warning when the debugger detects a mismatch between the MD5
checksum in the DWARF 5 line table and the file on disk. The warning is
printed only once per file.
This PR adds a statistics provider cache, which allows an individual
target to keep a rolling tally of it's total time and number of
invocations for a given summary provider. This information is then
available in statistics dump to help slow summary providers, and gleam
more into insight into LLDB's time use.
Now that more parts of LLDB know about SupportFiles, avoid going through
FileSpec (and losing the Checksum in the process). Instead, use the
SupportFile directly.
This patch updates the source cache dump command to print both the
actual (on-disk) checksum and the expected (line table) checksum. To
achieve that we now read and store the on-disk checksum in the cached
object. The same information will be used in a future path to print a
warning when the checksums differ.
This patch removes all of the Set.* methods from Status.
This cleanup is part of a series of patches that make it harder use the
anti-pattern of keeping a long-lives Status object around and updating
it while dropping any errors it contains on the floor.
This patch is largely NFC, the more interesting next steps this enables
is to:
1. remove Status.Clear()
2. assert that Status::operator=() never overwrites an error
3. remove Status::operator=()
Note that step (2) will bring 90% of the benefits for users, and step
(3) will dramatically clean up the error handling code in various
places. In the end my goal is to convert all APIs that are of the form
` ResultTy DoFoo(Status& error)
`
to
` llvm::Expected<ResultTy> DoFoo()
`
How to read this patch?
The interesting changes are in Status.h and Status.cpp, all other
changes are mostly
` perl -pi -e 's/\.SetErrorString/ = Status::FromErrorString/g' $(git
grep -l SetErrorString lldb/source)
`
plus the occasional manual cleanup.
Compilers and language runtimes often use helper functions that are
fundamentally uninteresting when debugging anything but the
compiler/runtime itself. This patch introduces a user-extensible
mechanism that allows for these frames to be hidden from backtraces and
automatically skipped over when navigating the stack with `up` and
`down`.
This does not affect the numbering of frames, so `f <N>` will still
provide access to the hidden frames. The `bt` output will also print a
hint that frames have been hidden.
My primary motivation for this feature is to hide thunks in the Swift
programming language, but I'm including an example recognizer for
`std::function::operator()` that I wished for myself many times while
debugging LLDB.
rdar://126629381
Example output. (Yes, my proof-of-concept recognizer could hide even
more frames if we had a method that returned the function name without
the return type or I used something that isn't based off regex, but it's
really only meant as an example).
before:
```
(lldb) thread backtrace --filtered=false
* thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
* frame #0: 0x0000000100001f04 a.out`foo(x=1, y=1) at main.cpp:4:10
frame #1: 0x0000000100003a00 a.out`decltype(std::declval<int (*&)(int, int)>()(std::declval<int>(), std::declval<int>())) std::__1::__invoke[abi:se200000]<int (*&)(int, int), int, int>(__f=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:149:25
frame #2: 0x000000010000399c a.out`int std::__1::__invoke_void_return_wrapper<int, false>::__call[abi:se200000]<int (*&)(int, int), int, int>(__args=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:216:12
frame #3: 0x0000000100003968 a.out`std::__1::__function::__alloc_func<int (*)(int, int), std::__1::allocator<int (*)(int, int)>, int (int, int)>::operator()[abi:se200000](this=0x000000016fdff280, __arg=0x000000016fdff224, __arg=0x000000016fdff220) at function.h:171:12
frame #4: 0x00000001000026bc a.out`std::__1::__function::__func<int (*)(int, int), std::__1::allocator<int (*)(int, int)>, int (int, int)>::operator()(this=0x000000016fdff278, __arg=0x000000016fdff224, __arg=0x000000016fdff220) at function.h:313:10
frame #5: 0x0000000100003c38 a.out`std::__1::__function::__value_func<int (int, int)>::operator()[abi:se200000](this=0x000000016fdff278, __args=0x000000016fdff224, __args=0x000000016fdff220) const at function.h:430:12
frame #6: 0x0000000100002038 a.out`std::__1::function<int (int, int)>::operator()(this= Function = foo(int, int) , __arg=1, __arg=1) const at function.h:989:10
frame #7: 0x0000000100001f64 a.out`main(argc=1, argv=0x000000016fdff4f8) at main.cpp:9:10
frame #8: 0x0000000183cdf154 dyld`start + 2476
(lldb)
```
after
```
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
* frame #0: 0x0000000100001f04 a.out`foo(x=1, y=1) at main.cpp:4:10
frame #1: 0x0000000100003a00 a.out`decltype(std::declval<int (*&)(int, int)>()(std::declval<int>(), std::declval<int>())) std::__1::__invoke[abi:se200000]<int (*&)(int, int), int, int>(__f=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:149:25
frame #2: 0x000000010000399c a.out`int std::__1::__invoke_void_return_wrapper<int, false>::__call[abi:se200000]<int (*&)(int, int), int, int>(__args=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:216:12
frame #6: 0x0000000100002038 a.out`std::__1::function<int (int, int)>::operator()(this= Function = foo(int, int) , __arg=1, __arg=1) const at function.h:989:10
frame #7: 0x0000000100001f64 a.out`main(argc=1, argv=0x000000016fdff4f8) at main.cpp:9:10
frame #8: 0x0000000183cdf154 dyld`start + 2476
Note: Some frames were hidden by frame recognizers
```
Reapply #100443 and #101770. These were originally reverted due to a
test failure and an MSAN failure. I changed the test attribute to
restrict to x86 (following the other existing tests). I could not
reproduce the test or the MSAN failure and no repo steps were provided.
Make all `Progress` destructions to cause `progressEnd` events,
regardless of the value of `m_completed` before the destruction.
Currently, a `Progress` instance with `m_completed != 0 && m_complete !=
m_total` will cause a `progressUpdate` event (not `progressEnd`) at
destruction and. This contradicts with the classdoc: "a progress completed
update is reported even if the user doesn't explicitly cause one to be sent."
In #100443, Mach-o and Minidump now only call process API's that take a
`SaveCoreOption` as the container for the style and information if a
thread should be included in the core or not. This introduced a bug
where in subsequent method calls we were not honoring the defaults of
both implementations.
~~To solve this I have made a copy of each SaveCoreOptions that is
mutable by the respective plugin. Originally I wanted to leave the
SaveCoreOptions as non const so these default value mutations could be
shown back to the user. Changing that behavior is outside of the scope
of this bugfix, but is context for why we are making a copy.~~
Removed const on the savecoreoptions so defaults can be inspected by the
user
CC: @Michael137
In #98403 I enabled the SBSaveCoreOptions object, which allows users via
the scripting API to define what they want saved into their core file.
As the first option I've added a threadlist, so users can scan and
identify which threads and corresponding stacks they want to save.
In order to support this, I had to add a new method to `Process.h` on
how we identify which threads are to be saved, and I had to change the
book keeping in minidump to ensure we don't double save the stacks.
Important to @jasonmolenda I also changed the MachO coredump to accept
these new APIs.
Currently a Module has a std::optional<UnwindTable> which is created
when the UnwindTable is requested from outside the Module. The idea is
to delay its creation until the Module has an ObjectFile initialized,
which will have been done by the time we're doing an unwind.
However, Module::GetUnwindTable wasn't doing any locking, so it was
possible for two threads to ask for the UnwindTable for the first time,
one would be created and returned while another thread would create one,
destroy the first in the process of emplacing it. It was an uncommon
crash, but it was possible.
Grabbing the Module's mutex would be one way to address it, but when
loading ELF binaries, we start creating the SymbolTable on one thread
(ObjectFileELF) grabbing the Module's mutex, and then spin up worker
threads to parse the individual DWARF compilation units, which then try
to also get the UnwindTable and deadlock if they try to get the Module's
mutex.
This changes Module to have a concrete UnwindTable as an ivar, and when
it adds an ObjectFile or SymbolFileVendor, it will call the Update
method on it, which will re-evaluate which sections exist in the
ObjectFile/SymbolFile. UnwindTable used to have an Initialize method
which set all the sections, and an Update method which would set some of
them if they weren't set. I unified these with the Initialize method
taking a `force` option to re-initialize the section pointers even if
they had been done already before.
This is addressing a rare crash report we've received, and also a
failure Adrian spotted on the -fsanitize=address CI bot last week, it's
still uncommon with ASAN but it can happen with the standard testsuite.
rdar://128876433
This patch introduces a new `template` multiword sub-command to the
`scripting` top-level command. As the name suggests, this sub-command
operates on scripting templates, and currently has the ability to
automatically discover the various scripting extensions that lldb
supports.
This was previously reviewed in #97273.
Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
This patch introduces a new `template` multiword sub-command to the
`scripting` top-level command. As the name suggests, this sub-command
operates on scripting templates, and currently has the ability to
automatically discover the various scripting extensions that lldb
supports.
This was previously reviewed in #97273.
Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
This patch introduces a new `template` multiword sub-command to the
`scripting` top-level command. As the name suggests, this sub-command
operates on scripting templates, and currently has the ability to
automatically discover the various scripting extensions that lldb
supports.
Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
This PR adds `SBSaveCoreOptions`, which is a container class for options
when LLDB is taking coredumps. For this first iteration this container
just keeps parity with the extant API of `file, style, plugin`. In the
future this options object can be extended to allow users to take a
subset of their core dumps.
When doing firmware/kernel debugging, it is frequent that binaries and
debug info need to be retrieved / downloaded, and the lack of progress
reports made for a poor experience, with lldb seemingly hung while
downloading things over the network. This PR adds progress reports to
the critical sites for these use cases.
This improves the handling of `$` (dollar) characters in summary strings in the
following ways:
1. When a `$` is not followed by an open paren (`{`), it should be treated as a literal
character and preserved in the output. Previously, the dollar would be consumed by the
parser and not shown in the output.
2. When a `$` is the last character of a format string, this change eliminates the
infinite loop lldb would enter into.
rdar://131392446
This reverts commit d9e659c538516036e40330b6a98160cbda4ff100.
I could not reproduce the Mac OS ASAN failure locally but I narrowed it
down to the test `test_many_fields_same_enum`. This test shares an enum
between x0, which is 64 bit, and cpsr, which is 32 bit.
My theory is that when it does `register read x0`, an enum type is
created where the undlerying enumerators are 64 bit, matching the
register size.
Then it does `register read cpsr` which used the cached enum type, but
this register is 32 bit. This caused lldb to try to read an 8 byte value
out of a 4 byte allocation:
READ of size 8 at 0x60200014b874 thread T0
<...>
=>0x60200014b800: fa fa fd fa fa fa fd fa fa fa fd fa fa fa[04]fa
To fix this I've added the register's size in bytes to the constructed
enum type's name. This means that x0 uses:
__lldb_register_fields_enum_some_enum_8
And cpsr uses:
__lldb_register_fields_enum_some_enum_4
If any other registers use this enum and are read, they will use the
cached type as long as their size matches, otherwise we make a new type.
This teaches lldb to parse the enum XML elements sent by lldb-server,
and make use of the information in `register read` and `register info`.
The format is described in
https://sourceware.org/gdb/current/onlinedocs/gdb.html/Enum-Target-Types.html.
The target XML parser will drop any invalid enum or evalue. If we find
multiple evalue for the same value, we will use the last one we find.
The order of evalues from the XML is preserved as there may be good
reason they are not in numerical order.
This change by itself has no measurable effect on the LLDB
testsuite. I'm making it in preparation for threading through more
errors in the Swift language plugin.
Create additional helper functions for the ValueObject class, for:
- returning the value as an APSInt or APFloat
- additional type casting options
- additional ways to create ValueObjects from various types of data
- dereferencing a ValueObject
These helper functions are needed for implementing the Data Inspection
Language, described in
https://discourse.llvm.org/t/rfc-data-inspection-language/69893
The the function is doing two fairly different things, depending on how
it is called. While this allows for some code reuse, it also makes it
hard to override it correctly. Possibly for this reason
ValueObjectSynthetic overerides GetChildAtIndex instead, which forces it
to reimplement some of its functionality, most notably caching of
generated children.
Splitting this up makes it easier to move the caching to a common place
(and hopefully makes the code easier to follow in general).
UpdateFormatsIfNeeded has hardcoded the call to GetFormat with no
dynamic values. GetFormat will try to find the synthetic children of the
ValueObject, and passing the wrong one can fail, which can be bad for
performance but should not be user visible. Fix the performace bug by
passing the dynamic value type of the ValueObject.
rdar://122506593
Change the signature of `DWARFExpression::Evaluate` and
`DWARFExpressionList::Evaluate` to return an `llvm::Expected` instead of a
boolean. This eliminates the `Status` output parameter and generally improves
error handling.
Reduce false positive identification of C names as Dlang mangled names. This happens
when a C function uses the prefix `_D`.
The [Dlang ABI](https://dlang.org/spec/abi.html#name_mangling) shows that mangled names
have a length immediately following the `_D` prefix. This change checks for a digit
after the `_D` prefix, when identifying the mangling scheme of a symbol. This doesn't
prevent false positives entirely, but does make it less likely.
This reverts commit fe82a3da36196157c0caa1ef2505186782f750d1.
This broke LLDB on MacOS due to a missing symbol during linking.
The fix has been applied in c6c08eee37bada190bd1aa4593c88a5e2c8cdaac.
Original commit message:
The terminfo dependency introduces a significant nonhermeticity into the
build. It doesn't respect `--no-undefined-version` meaning that it's not
a dependency that can be built with Clang 17+. This forces maintainers
of source-based distributions to implement patches or ignore linker
errors.
Remove it to reduce the closure size and improve portability of
LLVM-based tools. Users can still use command line arguments to toggle
color support expliticly.
Fixes#75490Closes#53294#23355
This adds new SB API calls and classes to allow a user of the SB API to obtain an address range from SBFunction and SBBlock. This is a second attempt to land the reverted PR #92014.
The terminfo dependency introduces a significant nonhermeticity into the
build. It doesn't respect `--no-undefined-version` meaning that it's not
a dependency that can be built with Clang 17+. This forces maintainers
of source-based distributions to implement patches or ignore linker
errors.
Remove it to reduce the closure size and improve portability of
LLVM-based tools. Users can still use command line arguments to toggle
color support expliticly.
Fixes#75490Closes#53294#23355
# Motivation
Individual callers of `SBDebugger::SetDestroyCallback()` might think
that they have registered their callback and expect it to be called when
the debugger is destroyed. In reality, only the last caller survives,
and all previous callers are forgotten, which might be a surprise to
them. Worse, if this is called in a race condition, which callback
survives is less predictable, which may case confusing behavior
elsewhere.
# This PR
Allows multiple destroy callbacks to be registered and all called when
the debugger is destroyed.
**EDIT**: Adds two new APIs: `AddDestroyCallback()` and
`ClearDestroyCallback()`. `SetDestroyCallback()` will first clear then
add the given callback. Tests are added for the new APIs.
## Tests
```
bin/llvm-lit -sv ../external/llvm-project/lldb/test/API/python_api/debugger/TestDebuggerAPI.py
```
## (out-dated, see comments below) Semantic change to
`SetDestroyCallback()`
~~Currently, the method overwrites the old callback with the new one.
With this PR, it will NOT overwrite. Instead, it will hold on to both.
Both callbacks get called during destroy.~~
~~**Risk**: Although the documentation of `SetDestroyCallback()` (see
[C++](https://lldb.llvm.org/cpp_reference/classlldb_1_1SBDebugger.html#afa1649d9453a376b5c95888b5a0cb4ec)
and
[python](https://lldb.llvm.org/python_api/lldb.SBDebugger.html#lldb.SBDebugger.SetDestroyCallback))
doesn't really specify the behavior, there is a risk: if existing call
sites rely on the "overwrite" behavior, they will be surprised because
now the old callback will get called. But as the above said, the current
behavior of "overwrite" itself might be unintended, so I don't
anticipate users to rely on this behavior. In short, this risk might be
less of a problem if we correct it sooner rather than later (which is
what this PR is trying to do).~~
## (out-dated, see comments below) Implementation
~~The implementation holds a `std::vector<std::pair<callback, baton>>`.
When `SetDestroyCallback()` is called, callbacks and batons are appended
to the `std::vector`. When destroy event happen, the `(callback, baton)`
pairs are invoked FIFO. Finally, the `std::vector` is cleared.~~
# (out-dated, see comments below) Alternatives considered
~~Instead of changing `SetDestroyCallback()`, a new method
`AddDestroyCallback()` can be added, which use the same
`std::vector<std::pair<>>` implementation. Together with
`ClearDestroyCallback()` (see below), they will replace and deprecate
`SetDestroyCallback()`. Meanwhile, in order to be backward compatible,
`SetDestroyCallback()` need to be updated to clear the `std::vector` and
then add the new callback. Pros: The end state is semantically more
correct. Cons: More steps to take; potentially maintaining an
"incorrect" behavior (of "overwrite").~~
~~A new method `ClearDestroyCallback()` can be added. Might be
unnecessary at this point, because workflows which need to set then
clear callbacks may exist but shouldn't be too common at least for now.
Such method can be added later when needed.~~
~~The `std::vector` may bring slight performance drawback if its
implementation doesn't handle small size efficiently. However, even if
that's the case, this path should be very cold (only used during init
and destroy). Such performance drawback should be negligible.~~
~~A different implementation was also considered. Instead of using
`std::vector`, the current `m_destroy_callback` field can be kept
unchanged. When `SetDestroyCallback()` is called, a lambda function can
be stored into `m_destroy_callback`. This lambda function will first
call the old callback, then the new one. This way, `std::vector` is
avoided. However, this implementation is more complex, thus less
readable, with not much perf to gain.~~
---------
Co-authored-by: Roy Shi <royshi@meta.com>