Summary:
For index-based code completion, send an asynchronous speculative index
request, based on the index request for the last code completion on the same
file and the filter text typed before the cursor, before sema code completion
is invoked. This can reduce the code completion latency (by roughly latency of
sema code completion) if the speculative request is the same as the one
generated for the ongoing code completion from sema. As a sequence of code
completions often have the same scopes and proximity paths etc, this should be
effective for a number of code completions.
Trace with speculative index request:{F6997544}
Reviewers: hokein, ilya-biryukov
Reviewed By: ilya-biryukov
Subscribers: javed.absar, jfb, MaskRay, jkorous, arphaman, kadircet, cfe-commits
Differential Revision: https://reviews.llvm.org/D50962
llvm-svn: 340604
Summary:
Will be used for updating the dynamic index on updates to the open files.
Currently we collect only information coming from the preamble
AST. This has a bunch of limitations:
- Dynamic index misses important information from the body of the
file, e.g. locations of definitions.
- XRefs cannot be collected at all, since we can only obtain full
information for the current file (preamble is parsed with skipped
function bodies, therefore not reliable).
This patch only adds the new callback, actually updates to the index
will be done in a follow-up patch.
Reviewers: hokein
Reviewed By: hokein
Subscribers: kadircet, javed.absar, ioeric, MaskRay, jkorous, arphaman, cfe-commits
Differential Revision: https://reviews.llvm.org/D50847
llvm-svn: 340401
Summary:
This allows implementations like different symbol indexes to know what
the current active file is. For example, some customized index implementation
might decide to only return results for some files.
Reviewers: ilya-biryukov
Reviewed By: ilya-biryukov
Subscribers: javed.absar, MaskRay, jkorous, arphaman, cfe-commits
Differential Revision: https://reviews.llvm.org/D50446
llvm-svn: 339320
Summary:
To avoid doing extra work of processing headers in the preamble
mutilple times in parallel.
Reviewers: sammccall
Reviewed By: sammccall
Subscribers: javed.absar, ioeric, MaskRay, jkorous, cfe-commits
Differential Revision: https://reviews.llvm.org/D48940
llvm-svn: 336538
Summary:
After this commit, clangd will only keep the last 3 accessed ASTs in
memory. Preambles for each of the opened files are still kept in
memory to make completion and AST rebuilds fast.
AST rebuilds are usually fast enough, but having the last ASTs in
memory still considerably improves latency of operations like
findDefinition and documeneHighlight, which are often sent multiple
times a second when moving around the code. So keeping some of the last
accessed ASTs in memory seems like a reasonable tradeoff.
Reviewers: sammccall
Reviewed By: sammccall
Subscribers: malaperle, arphaman, klimek, javed.absar, ioeric, MaskRay, jkorous, cfe-commits
Differential Revision: https://reviews.llvm.org/D47063
llvm-svn: 333737
Summary:
This is more efficient and avoids data races when reading files that
come from the preamble. The staleness can occur when reading a file
from disk that changed after the preamble was built. This can lead to
crashes, e.g. when parsing comments.
We do not to rely on symbols from the main file anyway, since any info
that those provide can always be taken from the AST.
Reviewers: ioeric, sammccall
Reviewed By: ioeric
Subscribers: malaperle, klimek, javed.absar, MaskRay, jkorous, cfe-commits
Differential Revision: https://reviews.llvm.org/D47272
llvm-svn: 333196
Summary:
It was previously an easy way to concurrently access a mutable vfs,
which is a recipe for disaster.
Reviewers: sammccall
Reviewed By: sammccall
Subscribers: klimek, jkorous-apple, cfe-commits, ioeric
Differential Revision: https://reviews.llvm.org/D44463
llvm-svn: 327537
Context can do what Tagged was intended to support (snapshot filesystems),
and less intrusively.
getTaggedFileSystem() no longer needs a filename.
Cleanups while here:
- code-complete now returns errors as Expected, like other functions
- added an alias Callback<T> for the usual callback function type
llvm-svn: 327344
Summary:
The new implementation attaches notes to diagnostic message and shows
the original diagnostics in the message of the note.
Reviewers: hokein, ioeric, sammccall
Reviewed By: sammccall
Subscribers: klimek, mgorny, cfe-commits, jkorous-apple
Differential Revision: https://reviews.llvm.org/D44142
llvm-svn: 327282
Summary:
Don't actually start building ASTs for new revisions until either:
- 500ms have passed since the last revision, or
- we actually need the revision for something (or to unblock the queue)
In practice, this avoids the "first keystroke results in diagnostics" problem.
This is kind of awkward to test, and the test is pretty bad.
It can be observed nicely by capturing a trace, though.
Reviewers: hokein, ilya-biryukov
Subscribers: klimek, jkorous-apple, ioeric, cfe-commits
Differential Revision: https://reviews.llvm.org/D43648
llvm-svn: 326546
Summary:
Through the C++ API, we support for a given snapshot version:
- Yes: make sure we generate diagnostics for exactly this version
- Auto: generate eventually-consistent diagnostics for at least this version
- No: don't generate diagnostics for this version
Eventually auto should be debounced for better UX.
Through LSP, we force diagnostics for initial load (bypassing future debouncing)
and all updates follow the "auto" policy.
This is complicated to implement under the CancellationFlag design, so
rewrote that part to just inspect the queue instead.
It turns out we never pass None to the diagnostics callback, so remove Optional
from the signature. The questionable behavior of not invoking the callback at
all if CppFile::rebuild fails is not changed.
Reviewers: ilya-biryukov
Subscribers: klimek, jkorous-apple, ioeric, cfe-commits
Differential Revision: https://reviews.llvm.org/D43518
llvm-svn: 325774
Summary:
This has a bit of a blast radius, but I think there's enough value in "forcing"
us to give names to these async tasks for debugging. Guessing about what
multithreaded code is doing is so unfun...
The "file" param attached to the tasks may seem to be redundant with the thread
names, but note that thread names are truncated to 15 chars on linux!
We'll be lucky to get the whole basename...
Reviewers: ilya-biryukov
Subscribers: klimek, jkorous-apple, ioeric, cfe-commits
Differential Revision: https://reviews.llvm.org/D43388
llvm-svn: 325480
Summary:
LSP has asynchronous semantics, being able to block on an async operation
completing is unneccesary and leads to tighter coupling with the threading.
In practice only tests depend on this, so we add a general-purpose "block until
idle" function to the scheduler which will work for all operations.
To get this working, fix a latent condition-variable bug in ASTWorker, and make
AsyncTaskRunner const-correct.
Reviewers: ilya-biryukov
Subscribers: klimek, jkorous-apple, ioeric, cfe-commits
Differential Revision: https://reviews.llvm.org/D43127
llvm-svn: 324990
Initially submitted as r324356 and reverted in r324386.
This change additionally contains a fix to crashes of the buildbots.
The source of the crash was undefined behaviour caused by
std::future<> whose std::promise<> was destroyed without calling
set_value().
llvm-svn: 324575
Summary:
In the new threading model clangd creates one thread per file to manage
the AST and one thread to process each of the incoming requests.
The number of actively running threads is bounded by the semaphore to
avoid overloading the system.
Reviewers: sammccall
Reviewed By: sammccall
Subscribers: klimek, mgorny, jkorous-apple, ioeric, hintonda, cfe-commits
Differential Revision: https://reviews.llvm.org/D42573
llvm-svn: 324356
Summary:
Instead of passing Context explicitly around, we now have a thread-local
Context object `Context::current()` which is an implicit argument to
every function.
Most manipulation of this should use the WithContextValue helper, which
augments the current Context to add a single KV pair, and restores the
old context on destruction.
Advantages are:
- less boilerplate in functions that just propagate contexts
- reading most code doesn't require understanding context at all, and
using context as values in fewer places still
- fewer options to pass the "wrong" context when it changes within a
scope (e.g. when using Span)
- contexts pass through interfaces we can't modify, such as VFS
- propagating contexts across threads was slightly tricky (e.g.
copy vs move, no move-init in lambdas), and is now encapsulated in
the threadpool
Disadvantages are all the usual TLS stuff - hidden magic, and
potential for higher memory usage on threads that don't use the
context. (In practice, it's just one pointer)
Reviewers: ilya-biryukov
Subscribers: klimek, jkorous-apple, ioeric, cfe-commits
Differential Revision: https://reviews.llvm.org/D42517
llvm-svn: 323872
Summary:
We now provide an abstraction of Scheduler that abstracts threading
and resource management in ClangdServer.
No changes to behavior are intended with an exception of changed error
messages.
This patch is preliminary work to allow a revamped threading
implementation that will move the threading code out of CppFile.
Reviewers: sammccall, bkramer, jkorous-apple
Reviewed By: sammccall
Subscribers: hokein, mgorny, hintonda, ioeric, jkorous-apple, cfe-commits, klimek
Differential Revision: https://reviews.llvm.org/D42174
llvm-svn: 323851
Eric Liu