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  1. 06 Dec, 2018 1 commit
    • tzik's avatar
      Replace %RunMicrotasks with %PerformMicrotaskCheckpoint · 07011cc4
      tzik authored 
      This replaces Runtime_RunMicrotasks with Runtime_PerformMicrotaskCheckpoint.

RunMicrotasks forcibly runs Microtasks even when the microtasks are suppressed,
and may causes nested Microtasks in a problematic way. E.g. that confuses
v8::MicrotasksScope::IsRunningMicrotasks() and GetEnteredOrMicrotaskContext().

OTOH, PerformMicrotaskCheckpoint() doesn't run cause the failure as it
respects the microtask suppressions.

As all existing tests don't call RunMicrotasks() in the suppressed situation
(like Promise.resolve().then(()=>{%RunMicrotasks();})), this change should
not affect to these tests.

Change-Id: Ib043a0cc8e482e022d375084d65ea98a6f54ef3d
Reviewed-on: https://chromium-review.googlesource.com/c/1360095Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Commit-Queue: Taiju Tsuiki <tzik@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58068}
      07011cc4
  3. 10 Oct, 2018 1 commit
    • Benedikt Meurer's avatar
      [async] Improve async function handling. · 0038e5f0
      Benedikt Meurer authored 
      This change introduces new intrinsics used to desugar async functions
in the Parser and the BytecodeGenerator, namely we introduce a new
%_AsyncFunctionEnter intrinsic that constructs the generator object
for the async function (and in the future will also create the outer
promise for the async function). This generator object is internal
and never escapes to user code, plus since async functions don't have
a "prototype" property, we can just a single map here instead of tracking
the prototype/initial_map on every async function. This saves one word
per async function plus one initial_map per async function that was
invoked at least once.

We also introduce two new intrinsics %_AsyncFunctionReject, which
rejects the outer promise with the caught exception, and another
%_AsyncFunctionResolve, which resolves the outer promise with the
right hand side of the `return` statement. These functions also perform
the DevTools part of the job (aka popping from the promise stack and
sending the debug event). This allows us to get rid of the implicit
try-finally from async functions completely; because the finally
block only called to the %AsyncFunctionPromiseRelease builtin, which
was used to inform DevTools.

In essence we now turn an async function like

```js
async function f(x) { return await bar(x); }
```

into something like this (in Parser and BytecodeGenerator respectively):

```
function f(x) {
  .generator_object = %_AsyncFunctionEnter(.closure, this);
  .promise = %AsyncFunctionCreatePromise();
  try {
    .tmp = await bar(x);
    return %_AsyncFunctionResolve(.promise, .tmp);
  } catch (e) {
    return %_AsyncFunctionReject(.promise, e);
  }
}
```

Overall the bytecode for async functions gets significantly shorter
already (and will get even shorter once we put the outer promise into
the async function generator object). For example the bytecode for a
simple async function

```js
async function f(x) { return await x; }
```

goes from 175 bytes to 110 bytes (a ~38% reduction in size), which
is in particular due to the simplification around the try-finally
removal.

Overall this seems to improve the doxbee-async-es2017-native test by
around 2-3%. On the test case mentioned in v8:8276 we go from
1124ms to 441ms, which corresponds to a 60% reduction in total
execution time!

Tbr: marja@chromium.org
Bug: v8:7253, v8:7522, v8:8276
Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel;luci.chromium.try:linux_chromium_rel_ng;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: Id29dc92de7490b387ff697860c900cee44c9a7a4
Reviewed-on: https://chromium-review.googlesource.com/c/1269041
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarSathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
Reviewed-by: 's avatarMaya Lekova <mslekova@chromium.org>
Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56502}
      0038e5f0
  5. 05 Jul, 2018 1 commit
  7. 03 Jul, 2018 3 commits
    • Alexey Kozyatinskiy's avatar
      Reland "[debug] liveedit in native" · 5505c664
      Alexey Kozyatinskiy authored 
      This is a reland of 3dfaf826

Original change's description:
> [debug] liveedit in native
>
> Liveedit step-by-step:
> 1. calculate diff between old source and new source,
> 2. map function literals from old source to new source,
> 3. create new script for new_source,
> 4. mark literals with changed code as changed, all others as unchanged,
> 5. check that for changed literals there are no:
>   - running generators in the heap,
>   - non droppable frames (e.g. running generator) above them on stack.
> 6. mark the bottom most frame with changed function as scheduled for
>    restart if any.
> 7. for unchanged functions:
>   - deoptimize,
>   - remove from cache,
>   - update source positions,
>   - move to new script,
>   - reset feedback information and preparsed scope information if any,
>   - replace any sfi in constant pool with changed one if any.
> 8. for changed functions:
>   - deoptimize
>   - remove from cache,
>   - reset feedback information,
>   - update all links from js functions to old shared with new one.
> 9. swap scripts.
>
> TBR=ulan@chromium.org
>
> Bug: v8:7862,v8:5713
> Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel;luci.chromium.try:linux_chromium_rel_ng;master.tryserver.blink:linux_trusty_blink_rel
> Change-Id: I8f6f6156318cc82d6f36d7ebc1c9f7d5f3aa1461
> Reviewed-on: https://chromium-review.googlesource.com/1105493
> Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
> Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#54146}

TBR=dgozman@chromium.org

Bug: v8:7862, v8:5713
Change-Id: I163ed2fd2ca3115ba0de74cb35a6fac9e40fdd94
Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel;luci.chromium.try:linux_chromium_rel_ng;master.tryserver.blink:linux_trusty_blink_rel
Reviewed-on: https://chromium-review.googlesource.com/1124879
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: 's avatarAleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54187}
      5505c664
    • Yang Guo's avatar
      Revert "[debug] liveedit in native" · 22594d10
      Yang Guo authored 
      This reverts commit 3dfaf826.

Reason for revert: Failures - https://ci.chromium.org/p/v8/builders/luci.v8.ci/V8%20Linux%20gcc%204.8/20394

Original change's description:
> [debug] liveedit in native
> 
> Liveedit step-by-step:
> 1. calculate diff between old source and new source,
> 2. map function literals from old source to new source,
> 3. create new script for new_source,
> 4. mark literals with changed code as changed, all others as unchanged,
> 5. check that for changed literals there are no:
>   - running generators in the heap,
>   - non droppable frames (e.g. running generator) above them on stack.
> 6. mark the bottom most frame with changed function as scheduled for
>    restart if any.
> 7. for unchanged functions:
>   - deoptimize,
>   - remove from cache,
>   - update source positions,
>   - move to new script,
>   - reset feedback information and preparsed scope information if any,
>   - replace any sfi in constant pool with changed one if any.
> 8. for changed functions:
>   - deoptimize
>   - remove from cache,
>   - reset feedback information,
>   - update all links from js functions to old shared with new one.
> 9. swap scripts.
> 
> TBR=ulan@chromium.org
> 
> Bug: v8:7862,v8:5713
> Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel;luci.chromium.try:linux_chromium_rel_ng;master.tryserver.blink:linux_trusty_blink_rel
> Change-Id: I8f6f6156318cc82d6f36d7ebc1c9f7d5f3aa1461
> Reviewed-on: https://chromium-review.googlesource.com/1105493
> Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
> Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#54146}

TBR=dgozman@chromium.org,ulan@chromium.org,yangguo@chromium.org,kozyatinskiy@chromium.org

Change-Id: I45df5b6f3abaf29e593c6ac11edefbd0177d0109
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7862, v8:5713
Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel;luci.chromium.try:linux_chromium_rel_ng;master.tryserver.blink:linux_trusty_blink_rel
Reviewed-on: https://chromium-review.googlesource.com/1124159Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54151}
      22594d10
    • Alexey Kozyatinskiy's avatar
      [debug] liveedit in native · 3dfaf826
      Alexey Kozyatinskiy authored 
      Liveedit step-by-step:
1. calculate diff between old source and new source,
2. map function literals from old source to new source,
3. create new script for new_source,
4. mark literals with changed code as changed, all others as unchanged,
5. check that for changed literals there are no:
  - running generators in the heap,
  - non droppable frames (e.g. running generator) above them on stack.
6. mark the bottom most frame with changed function as scheduled for
   restart if any.
7. for unchanged functions:
  - deoptimize,
  - remove from cache,
  - update source positions,
  - move to new script,
  - reset feedback information and preparsed scope information if any,
  - replace any sfi in constant pool with changed one if any.
8. for changed functions:
  - deoptimize
  - remove from cache,
  - reset feedback information,
  - update all links from js functions to old shared with new one.
9. swap scripts.

TBR=ulan@chromium.org

Bug: v8:7862,v8:5713
Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel;luci.chromium.try:linux_chromium_rel_ng;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I8f6f6156318cc82d6f36d7ebc1c9f7d5f3aa1461
Reviewed-on: https://chromium-review.googlesource.com/1105493Reviewed-by: 's avatarAleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: 's avatarDmitry Gozman <dgozman@chromium.org>
Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54146}
      3dfaf826
  9. 21 Jun, 2018 1 commit
  11. 04 Jun, 2018 1 commit
  13. 21 Mar, 2018 1 commit
  15. 07 Sep, 2017 3 commits
  17. 18 Jul, 2017 1 commit
  19. 14 Jul, 2017 1 commit
    • Alexey Kozyatinskiy's avatar
      [inspector] improve return position of explicit return in non-async function · 08965860
      Alexey Kozyatinskiy authored 
      Goal of this CL: explicit return from non-async function has position after
return expression as return position (will unblock [1]).

BytecodeArrayBuilder has SetStatementPosition and SetExpressionPosition methods.
If one of these methods is called then next generated bytecode will get passed
position. It's general treatment for most cases.
Unfortunately it doesn't work for Returns:
- debugger requires source positions exactly on kReturn bytecode in stepping
  implementation,
- BytecodeGenerator::BuildReturn and BytecodeGenerator::BuildAsyncReturn
  generates more then one bytecode and general solution will put return position
  on first generated bytecode,
- it's not easy to split BuildReturn function into two parts to allow something
  like following in BytecodeGenerator::VisitReturnStatement since generated
  bytecodes are actually controlled by execution_control().
..->BuildReturnPrologue();
..->SetReturnPosition(stmt);
..->Return();

In this CL we pass ReturnStatement through ExecutionControl and use it for
position when we emit return bytecode right here.

So this CL only will improve return position for returns inside of non-async
functions, I'll address async functions later.

[1] https://chromium-review.googlesource.com/c/543161/

Change-Id: Iede512c120b00c209990bf50c20e7d23dc0d65db
Reviewed-on: https://chromium-review.googlesource.com/560738
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: 's avatarAdam Klein <adamk@chromium.org>
Reviewed-by: 's avatarMichael Starzinger <mstarzinger@chromium.org>
Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46687}
      08965860
  21. 31 May, 2017 1 commit
  23. 30 May, 2017 1 commit
    • Aleksey Kozyatinskiy's avatar
      [inspector] moved var initialization break location before init expression (reland) · fb6a094d
      Aleksey Kozyatinskiy authored 
      This CL improves break locations for expressions like 'var a = <expr>'. Without CL we use <expr> position as break location for initialization statement, with this CL we use position of first character after '=' as position.
Benefits (see test for details):
 - only one break in expressions which includes mix of property lookup and calls, e.g. var p = Promise.resolve().then(x => x * 2),
 - removed redundant break location for expressions like: let { x, y } = { x: 1, y: 2}.
 
TBR=dgozman@chromium.org,rmcilroy@chromium.org,machenbach@chromium.org,marja@chromium.org,kozyatinskiy@chromium.org,devtools-reviews@chromium.org,v8-reviews@googlegroups.com
# Not skipping CQ checks because original CL landed > 1 day ago.
Bug: v8:5909

Change-Id: Ie84fa79afeed09e28cf8478ba610a0cfbfdfc294
Reviewed-on: https://chromium-review.googlesource.com/518116
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: 's avatarAleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45598}
      fb6a094d
  25. 29 May, 2017 1 commit
    • Michael Achenbach's avatar
      Revert "[inspector] moved var initialization break location before init expression" · ee1db48c
      Michael Achenbach authored 
      This reverts commit 7a9cc704.

Reason for revert: Changes layout tests:
https://build.chromium.org/p/client.v8.fyi/builders/V8-Blink%20Linux%2064/builds/15882

This is about:
inspector/sources/debugger/source-frame-inline-breakpoint-decorations.html

Original change's description:
> [inspector] moved var initialization break location before init expression
> 
> This CL improves break locations for expressions like 'var a = <expr>'. Without CL we use <expr> position as break location for initialization statement, with this CL we use position of first character after '=' as position.
> Benefits (see test for details):
> - only one break in expressions which includes mix of property lookup and calls, e.g. var p = Promise.resolve().then(x => x * 2),
> - removed redundant break location for expressions like: let { x, y } = { x: 1, y: 2}.
> 
> Bug: v8:5909
> Change-Id: I039d911903a2826c9859710a63ab0462c992e11b
> Reviewed-on: https://chromium-review.googlesource.com/513926
> Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
> Reviewed-by: Marja Hölttä <marja@chromium.org>
> Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#45530}

TBR=dgozman@chromium.org,marja@chromium.org,kozyatinskiy@chromium.org
# Not skipping CQ checks because original CL landed > 1 day ago.
Bug: v8:5909

Change-Id: Ibf84401e8050d3c84db219d983de2c6bba0f697f
Reviewed-on: https://chromium-review.googlesource.com/518102Reviewed-by: 's avatarMichael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45547}
      ee1db48c
  27. 25 May, 2017 1 commit
  29. 24 May, 2017 1 commit
    • jarin's avatar
      Make non-Module generators only context allocate parameters. · a957b0f4
      jarin authored 
      In particular, local variables should be allocated on stack (in bytecode register), and stored/loaded to the generator object on generator suspend/resume.

The CL is based on @adamk's change to scoping/parsers (https://chromium-review.googlesource.com/c/498538/), I only made the debugger cope with this change.

I should note that the CL changes the scope type of suspended generators from ScopeType.Closure to ScopeType.Local. In the future we might want to introduce ScopeType.SuspendedGenerator to make the distinction explicit.

Some of the changes in the tests have been made because the debugger functions do not return scopes of closed generators anymore. Generators should be allowed to throw away their internal state when they finish.

BUG=v8:6368

Review-Url: https://codereview.chromium.org/2898163002
Cr-Commit-Position: refs/heads/master@{#45515}
      a957b0f4
  31. 10 Mar, 2017 1 commit
  33. 27 Jan, 2017 1 commit
    • yangguo's avatar
      [liveedit] reimplement frame restarting. · 3f47c63d
      yangguo authored 
      Previously, when restarting a frame, we would rewrite all frames
between the debugger activation and the frame to restart to squash
them, and replace the return address with that of a builtin to
leave that rewritten frame, and restart the function by calling it.

We now simply remember the frame to drop to, and upon returning
from the debugger, we check whether to drop the frame, load the
new FP, and restart the function.

R=jgruber@chromium.org, mstarzinger@chromium.org
BUG=v8:5587

Review-Url: https://codereview.chromium.org/2636913002
Cr-Commit-Position: refs/heads/master@{#42725}
      3f47c63d
  35. 10 Jan, 2017 1 commit