Refactor cross file rename to use a Filesystem instead of a function for getting buffer contents of open files.
Depends on D94554
Reviewed By: sammccall
Differential Revision: https://reviews.llvm.org/D95043
Currently our strategy for getting header compile flags is something like:
A) look for flags for the header in compile_commands.json
This basically never works, build systems don't generate this info.
B) try to match to an impl file in compile_commands.json and use its flags
This only (mostly) works if the headers are in the same project.
C) give up and use fallback flags
This kind of works for stdlib in the default configuration, and
otherwise doesn't.
Obviously there are big gaps here.
This patch inserts a new attempt between A and B: if the header is
transitively included by any open file (whether same project or not),
then we use its compile command.
This doesn't make any attempt to solve some related problems:
- parsing non-self-contained header files in context (importing PP state)
- using the compile flags of non-opened candidate files found in the index
Fixes https://github.com/clangd/clangd/issues/123
Fixes https://github.com/clangd/clangd/issues/695
See https://github.com/clangd/clangd/issues/519
Differential Revision: https://reviews.llvm.org/D97351
This is obsoleted by the standard semanticTokens request family.
As well as the protocol details, this allows us to remove a bunch of plumbing
around pushing highlights to clients.
This should not land until the new protocol has feature parity, see D77702.
Differential Revision: https://reviews.llvm.org/D95576
The new trace event includes what's already in the queue when adding.
For tracers that follow contexts, the trace event will span the time that the action
spends in the queue.
For tracers that follow threads, the trace will be a tiny span on the enqueuing thread.
Differential Revision: https://reviews.llvm.org/D96027
This allows quick tasks without dependencies that
need to run fast to run ASAP. This is mostly useful
for code formatting.
----------------------------
This fixes something that's been annoying me:
- Open your IDE workspace and its 20 open files
- Clangd spends 5 minutes parsing it all
- In the meantime you start to work
- Save a file, trigger format-on-save, which hangs because clangd is busy
- You're stuck waiting until clangd is done parsing your files before the formatting and save takes place
Reviewed By: sammccall
Differential Revision: https://reviews.llvm.org/D94875
Many useful signals can be derived from a valid AST which is regularly updated by
the ASTWorker. `runWithPreamble` does not have access to the ParsedAST
but it can be provided access to some signals derived from a (possibly
stale) AST.
Differential Revision: https://reviews.llvm.org/D94424
clangd actions have various naming schemes, the most
common being PascalCase. This commit applies PascalCase
to all clangd actions, and fix the status rendering
in `renderTUAction` to look more consistent.
Reviewed By: sammccall
Differential Revision: https://reviews.llvm.org/D93546
There's an unfortunate collision between two features:
- we implicitly cancel certain requests when the file changes, to avoid
the queue getting clogged building old revisions to service stale requests
- we "reparse-if-needed" by synthesizing a file change, e.g. on didSave
We could explicitly mark these synthetic requests to avoid this, but
looking for changes in file content clutters our APIs less and is
arguably the correct thing to do in any case.
Fixes https://github.com/clangd/clangd/issues/620
SmallVector<T> with default size is now the recommended version (D92522).
Reviewed By: sammccall
Differential Revision: https://reviews.llvm.org/D92788
Summary:
This is considerably terser than the makeStringError and friends, and
avoids verbosity cliffs that discourage adding log information.
It follows the syntax used in log/elog/vlog/dlog that have been successful.
The main caveats are:
- it's strictly out-of-place in logger.h, though kind of fits thematically and
in implementation
- it claims the "error" identifier, which seems a bit too opinionated
to put higher up in llvm
I've updated some users of StringError mostly at random - there are lots
more mechanical changes but I'd like to get this reviewed before making
them all.
Reviewers: kbobyrev, hokein
Subscribers: mgorny, ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D83419
Summary:
I hit this while trying to add a config-over-LSP lit test, which I think
is an appropriate way to test this feature.
That needs a few more changes though...
Reviewers: kadircet
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D83802
Summary:
ClangdServer owns the question of exactly which config to create, but
TUScheduler/BackgroundIndex control threads and so decide at which point
to inject it.
Reviewers: kadircet
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D83095
Summary:
Instead of a notification, we make use of a CV and store the boolean on
LatestPreamble by converting it into an optional.
Depends on D80293.
Reviewers: sammccall
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D80784
Summary: Depends on D80198.
This patch implies ASTs might be built with stale preambles without
blocking for a fresh one. It also drops any guarantees on every preamble
version being built. In case of multiple preamble build requests, in
addition to being debounced.
Any preamble requested with a WantDiags::Yes will always be built, this
is ensured by blocking enqueueing of any subsequent reqest.
AST worker will still block for initial preamble to reduce duplicate
work.
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, jfb, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D80293
Summary:
This is achieved by calculating newly added includes and implicitly
parsing them as if they were part of the main file.
This also gets rid of the need for consistent preamble reads.
Reviewers: sammccall
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, mgrang, arphaman, jfb, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D77392
Summary:
We want to be sure they don't cause AST rebuilds or evict items from the cache.
D77847 is going to start sending spurious no-op changes (in case the preamble
was invalidated), this is cheap enough but we shouldn't regress that in future.
Reviewers: kadircet
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, jfb, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D78048
Summary:
This assertion was bad. It will show up once we start running preamble
thread async. Think about the following case:
- Update 1
builds a preamble, and an AST. Caches the AST.
- Update 2
Invalidates the cache, preamble hasn't changed.
- Update 3
Invalidates the cache, preamble hasn't changed
- Read
builds AST using preamble v1, and caches it.
preamble for v2 gets build, cache isn't invalidated since preamble is same.
generateDiags tries to reuse cached AST but latest version is 3 not 2, so
assertion fails.
Reviewers: sammccall
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D77664
Summary:
FileInputs are only written by ASTWorker thread, therefore it is safe
to read them without the lock inside that thread. It can still be read by other
threads through ASTWorker::getCurrentCompileCommand though.
This patch also gets rid of the smart pointer wrapping FileInputs as there is
never mutliple owners.
Reviewers: sammccall
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D77309
Summary:
This is another step for out-of-order preamble builds. To keep the
diagnostic behavior same, we only build ASTs either with "usable" preambles,
the ones that are fully applicable to a given ParseInput, or after building a
new preamble. Which is the same behaviour as what we do today. ASTs
built in the latter is called golden ASTs.
Reviewers: sammccall
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D76725
Summary:
TUStatus api had a single thread in mind. This introudces a section
action to represent state of the preamble thread. In the file status extension,
we keep old behavior almost the same. We only prepend current task with a
`parsing includes` if preamble thread is working. We omit the idle thread in the
output unless both threads are idle.
Reviewers: sammccall
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D76304
Summary:
First step to enable deferred preamble builds. Not intending to land it
alone, will have follow-ups that will implement full deferred build
functionality and will land after all of them are ready.
Reviewers: sammccall
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D76125
Summary:
This helps us prevent races when scheduler (or any other thread) tries
to read a request while it's still running.
Reviewers: sammccall
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D75927
Summary:
This ties to an LSP feature (diagnostic versioning) but really a lot
of the value is in being able to log what's happening with file versions
and queues more descriptively and clearly.
As such it's fairly invasive, for a logging patch :-\
Key decisions:
- at the LSP layer, we don't reqire the client to provide versions (LSP
makes it mandatory but we never enforced it). If not provided,
versions start at 0 and increment. DraftStore handles this.
- don't propagate magically using contexts, but rather manually:
addDocument -> ParseInputs -> (ParsedAST, Preamble, various callbacks)
Context-propagation would hide the versions from ClangdServer, which
would make producing good log messages hard
- within ClangdServer, treat versions as opaque and unordered.
std::string is a convenient type for this, and allows richer versions
for embedders. They're "mandatory" but "null" is a reasonable default.
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D75582
Summary:
Otherwise they can force us to build lots of snapshots that we don't need.
Particularly, try to do this for operations that are frequently
generated by editors without explicit user interaction, and where
editing the file makes the result less useful. (Code action
enumeration is a good example).
https://github.com/clangd/clangd/issues/298
This doesn't return the "right" LSP error code (ContentModified) to the client,
we need to teach the cancellation API to distinguish between different causes.
Reviewers: kadircet
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, jfb, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D75602
The goal of this patch is to maximize CPU utilization on multi-socket or high core count systems, so that parallel computations such as LLD/ThinLTO can use all hardware threads in the system. Before this patch, on Windows, a maximum of 64 hardware threads could be used at most, in some cases dispatched only on one CPU socket.
== Background ==
Windows doesn't have a flat cpu_set_t like Linux. Instead, it projects hardware CPUs (or NUMA nodes) to applications through a concept of "processor groups". A "processor" is the smallest unit of execution on a CPU, that is, an hyper-thread if SMT is active; a core otherwise. There's a limit of 32-bit processors on older 32-bit versions of Windows, which later was raised to 64-processors with 64-bit versions of Windows. This limit comes from the affinity mask, which historically is represented by the sizeof(void*). Consequently, the concept of "processor groups" was introduced for dealing with systems with more than 64 hyper-threads.
By default, the Windows OS assigns only one "processor group" to each starting application, in a round-robin manner. If the application wants to use more processors, it needs to programmatically enable it, by assigning threads to other "processor groups". This also means that affinity cannot cross "processor group" boundaries; one can only specify a "preferred" group on start-up, but the application is free to allocate more groups if it wants to.
This creates a peculiar situation, where newer CPUs like the AMD EPYC 7702P (64-cores, 128-hyperthreads) are projected by the OS as two (2) "processor groups". This means that by default, an application can only use half of the cores. This situation could only get worse in the years to come, as dies with more cores will appear on the market.
== The problem ==
The heavyweight_hardware_concurrency() API was introduced so that only *one hardware thread per core* was used. Once that API returns, that original intention is lost, only the number of threads is retained. Consider a situation, on Windows, where the system has 2 CPU sockets, 18 cores each, each core having 2 hyper-threads, for a total of 72 hyper-threads. Both heavyweight_hardware_concurrency() and hardware_concurrency() currently return 36, because on Windows they are simply wrappers over std:🧵:hardware_concurrency() -- which can only return processors from the current "processor group".
== The changes in this patch ==
To solve this situation, we capture (and retain) the initial intention until the point of usage, through a new ThreadPoolStrategy class. The number of threads to use is deferred as late as possible, until the moment where the std::threads are created (ThreadPool in the case of ThinLTO).
When using hardware_concurrency(), setting ThreadCount to 0 now means to use all the possible hardware CPU (SMT) threads. Providing a ThreadCount above to the maximum number of threads will have no effect, the maximum will be used instead.
The heavyweight_hardware_concurrency() is similar to hardware_concurrency(), except that only one thread per hardware *core* will be used.
When LLVM_ENABLE_THREADS is OFF, the threading APIs will always return 1, to ensure any caller loops will be exercised at least once.
Differential Revision: https://reviews.llvm.org/D71775
Summary:
- This option forces a preamble rebuild to handle the odd case
of a missing header file being added
Reviewers: sammccall
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, jfb, kadircet, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D73916
Summary:
Currently we delay AST rebuilds by 500ms after each edit, to wait for
further edits. This is a win if a rebuild takes 5s, and a loss if it
takes 50ms.
This patch sets debouncepolicy = clamp(min, ratio * rebuild_time, max).
However it sets min = max = 500ms so there's no policy change or actual
customizability - will do that in a separate patch.
See https://github.com/clangd/clangd/issues/275
Reviewers: hokein
Subscribers: ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D73873
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
Summary:
This is the initial version. The cross-file rename is purely based on
the index.
It is hidden under a command-line flag, and only available for a small set
of symbols.
Reviewers: ilya-biryukov, sammccall
Subscribers: merge_guards_bot, MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D69263