Commit Graph

5 Commits

Author SHA1 Message Date
Benedikt Meurer
16b0767adc [debug][inspector] Use first rather than closest break location.
In case there's no exact match for the breakable location in
SetBreakpoint(), don't try to find the syntactically closest break
location, but rather find the first possible break location in bytecode
order. In particular when trying to set a breakpoint in a line with
for-of or an array destruction, there's no point in going for the
syntactically closest to the beginning of the line, but rather go for
the semantically first, as the intiution for setting a breakpoint on a
line is that the debugger stops before it executes anything on said
line. In the example

```
var [^a, ^b] = ^func();
```

there are three possible break locations, and the correct one is the
last one as the call to func will happen first at runtime.

For generators that's currently broken because of the implicit initial
yield, and same with modules (see crbug.com/901819), so we keep the
previous behavior of finding the closest breakable location, and will
fix that independently in a follow up CL.

Bug: chromium:901819
Fixed: chromium:782461
Also-By: yangguo@chromium.org
Change-Id: Ie724c5cb08e5f4edd90a450d99e001dff06bbe7a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2696586
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72813}
2021-02-17 14:02:49 +00:00
Aleksey Kozyatinskiy
fb6a094db5 [inspector] moved var initialization break location before init expression (reland)
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: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45598}
2017-05-30 12:54:49 +00:00
Michael Achenbach
ee1db48cc3 Revert "[inspector] moved var initialization break location before init expression"
This reverts commit 7a9cc70492.

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/518102
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45547}
2017-05-29 07:03:23 +00:00
Alexey Kozyatinskiy
7a9cc70492 [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}
2017-05-25 14:51:17 +00:00
kozyatinskiy
fb78710c06 [inspector] removed call break location from for-of loop
There are two break locations at the same source location by desugaring:
- call iterator.next,
- before variable assignment.

Additionally location for for..of loops is moved from before "of" to before each variable expression.

We should not report first implicit call to avoid user confusion. User still able to go into .next function with both scenarios:
- when this call is reached by stepOver or stepInto from previous line,
- when this call is reached because of breakpoint at current line.

BUG=v8:6425
R=dgozman@chromium.org,jgruber@chromium.org

Review-Url: https://codereview.chromium.org/2893313002
Cr-Commit-Position: refs/heads/master@{#45509}
2017-05-24 12:12:53 +00:00