Commit Graph

13 Commits

Author SHA1 Message Date
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Sam McCall e2f3a7348d [clangd] Ensure that we reply to each call exactly once. NFC (I think!)
Summary:
In debug builds, getting this wrong will trigger asserts.
In production builds, it will send an error reply if none was sent,
and drop redundant replies. (And log).

No tests because this is always a programming error.
(We did have some cases of this, but I fixed them with the new dispatcher).

Reviewers: ioeric

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, jfb, kadircet, cfe-commits

Differential Revision: https://reviews.llvm.org/D53399

llvm-svn: 345144
2018-10-24 14:26:26 +00:00
Sam McCall d20d7989c6 [clangd] Remove JSON library in favor of llvm/Support/JSON
Summary:
The library has graduated from clangd to llvm/Support.
This is a mechanical change to move to the new API and remove the old one.

Main API changes:
 - namespace clang::clangd::json --> llvm::json
 - json::Expr --> json::Value
 - Expr::asString() etc --> Value::getAsString() etc
 - unsigned longs need a cast (due to r336541 adding lossless integer support)

Reviewers: ilya-biryukov

Subscribers: mgorny, ioeric, MaskRay, jkorous, omtcyfz, cfe-commits

Differential Revision: https://reviews.llvm.org/D49077

llvm-svn: 336549
2018-07-09 14:25:59 +00:00
Ilya Biryukov 8573defa2d [clangd] clang-format the source code. NFC
llvm-svn: 333537
2018-05-30 12:41:19 +00:00
Benjamin Kramer 08824567af [clangd] Prune some dead declarations. No functionality change.
llvm-svn: 330599
2018-04-23 14:58:18 +00:00
Sam McCall c901c5db78 [clangd] Tracing: name worker threads, and enforce naming scheduled async tasks
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
2018-02-19 09:56:28 +00:00
Sam McCall 7929d006d7 [clangd] Fix tracing now that spans lifetimes can overlap on a thread.
Summary:
The chrome trace viewer requires events within a thread to strictly nest.
So we need to record the lifetime of the Span objects, not the contexts.

But we still want to show the relationship between spans where a context crosses
threads, so do this with flow events (i.e. arrows).

Before: https://photos.app.goo.gl/q4Dd9u9xtelaXk1v1
After: https://photos.app.goo.gl/5RNLmAMLZR3unvY83

(This could stand some further improvement, in particular I think we want a
container span whenever we schedule work on a thread. But that's another patch)

Reviewers: ioeric

Subscribers: klimek, ilya-biryukov, jkorous-apple, cfe-commits

Differential Revision: https://reviews.llvm.org/D43272

llvm-svn: 325220
2018-02-15 08:40:54 +00:00
Sam McCall d1a7a37c22 [clangd] Pass Context implicitly using TLS.
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
2018-01-31 13:40:48 +00:00
Sam McCall 1b475a1ad0 [clangd] Modify the Span API so that Spans propagate with contexts.
Summary:
This is probably the right behavior for distributed tracers, and makes unpaired
begin-end events impossible without requiring Spans to be bound to a thread.

The API is conceptually clean but syntactically awkward. As discussed offline,
this is basically a naming problem and will go away if (when) we use TLS to
store the current context.

The apparently-unrelated change to onScopeExit are because its move semantics
broken if Func is POD-like since r322838. This is true of function pointers,
and the lambda I use here that captures two pointers only.
I've raised this issue on llvm-dev and will revert this part if we fix it in
some other way.

Reviewers: ilya-biryukov

Subscribers: klimek, jkorous-apple, ioeric, cfe-commits

Differential Revision: https://reviews.llvm.org/D42499

llvm-svn: 323511
2018-01-26 09:00:30 +00:00
Ilya Biryukov 12cdb4fd33 [clangd] Changed tracing interfaces
Summary:
EventTracer interface now contains two methods:
- spanEvent for events that have duration,
- instant for events that are instant.

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: klimek, luckygeck, cfe-commits

Differential Revision: https://reviews.llvm.org/D40489

llvm-svn: 320708
2017-12-14 15:33:38 +00:00
Ilya Biryukov ee27d2ebae [clangd] Implemented tracing using Context
Reviewers: sammccall, ioeric, hokein

Reviewed By: sammccall

Subscribers: klimek, luckygeck, cfe-commits

Differential Revision: https://reviews.llvm.org/D40488

llvm-svn: 320706
2017-12-14 15:04:59 +00:00
Sam McCall 9cfd9c9a9b [clangd] Tracing improvements
Summary:
[clangd] Tracing improvements

Compose JSON using JSONExpr
Allow attaching metadata to spans (and avoid it if tracing is off)
Attach IDs and responses of JSON RPCs to their spans

The downside is that large responses make the trace viewer sluggish.
We should make our responses less huge :-) Or fix trace viewer.

Reviewers: ilya-biryukov

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D40132

llvm-svn: 318928
2017-11-23 17:12:04 +00:00
Sam McCall 8567cb3720 Performance tracing facility for clangd.
Summary:
This lets you visualize clangd's activity on different threads over time,
and understand critical paths of requests and object lifetimes.
The data produced can be visualized in Chrome (at chrome://tracing), or
in a standalone copy of catapult (http://github.com/catapult-project/catapult)

This patch consists of:
 - a command line flag "-trace" that causes clangd to emit JSON trace data
 - an API (in Trace.h) allowing clangd code to easily add events to the stream
 - several initial uses of this API to capture JSON-RPC requests, builds, logs

Example result: https://photos.app.goo.gl/12L9swaz5REGQ1rm1

Caveats:
 - JSON serialization is ad-hoc (isn't it everywhere?) so the API is
   limited to naming events rather than attaching arbitrary metadata.
   I'd like to fix this (I think we could use a JSON-object abstraction).
 - The recording is very naive: events are written immediately by
   locking a mutex. Contention on the mutex might disturb performance.
 - For now it just traces instants or spans on the current thread.
   There are other things that make sense to show (cross-thread flows,
   non-thread resources such as ASTs). But we have to start somewhere.

Reviewers: ioeric, ilya-biryukov

Subscribers: cfe-commits, mgorny

Differential Revision: https://reviews.llvm.org/D39086

llvm-svn: 317193
2017-11-02 09:21:51 +00:00