Previously we'd attach source positions to implicit returns that are
generated when leaving an async function with a promise rejection. This
was due to the use of `kNoSourcePosition` on the `end_position` in the
`ReturnStatement` nodes as indicator to pick the return position from
the function literal, instead of really not putting a source position on
that specific `Return` bytecode.
This CL adds a dedicated marker to `ReturnStatement` to express that the
`BytecodeGenerator` should put the return position from the function
literal there instead of overloading the meaning of `kNoSourcePosition`.
Bug: chromium:901819, chromium:782461
Fixed: chromium:1199919, chromium:1201706
Change-Id: I3647e0c3d711e9c3d6ae44606b70ec92ad82e1cf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2859945
Auto-Submit: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74301}
Be explicit about source positions for `Return`s in the
BytecodeGenerator, and only do self-healing explicitly in the
`ReturnStatement` translation, where an end position of
`kNoSourcePosition` is turned into the return position of the
function literal.
This allows us to reason more easily about which `Return`s actually
receive a meaningful source position, and in particular it allows us
to construct the internal `Return`s for `yield` and `yield*` with no
source position attached to them. Previously they'd get the source
position for the implicit (final) return attached to it, which confused
the debugger and led to breakpoints being set in the completely wrong
spot.
Considering the simplified example
```
function* foo(){
var a = 1;
}
```
this would previously generate the following bytecode
```
0 : SwitchOnGeneratorState r0, [0], [1] { 0: @20 }
4 : Mov <closure>, r2
7 : Mov <this>, r3
13 E> 10 : InvokeIntrinsic [_CreateJSGeneratorObject], r2-r3
14 : Star0
13 E> 15 : SuspendGenerator r0, r0-r1, [0]
20 : ResumeGenerator r0, r0-r1
24 : Star2
25 : InvokeIntrinsic [_GeneratorGetResumeMode], r0-r0
29 : SwitchOnSmiNoFeedback [1], [2], [0] { 0: @39, 1: @36 }
33 : Ldar r2
13 E> 35 : Throw
36 : Ldar r2
30 S> 38 : Return <=========================== internal Return
27 S> 39 : LdaSmi [1]
41 : Star1
42 : LdaUndefined
30 S> 43 : Return
```
where everything between offset 4 and 42 corresponds to the implicit
yield at the beginning of every generator function, in particular the
code between 20 and 42 corresponds to that initial yields resumption
logic. Notice how the internal Return at offset 38 gets assigned the
source position of the function literal (the same as the implicit
return at the end). This confuses the debugger quite a bit when trying
to set a breakpoint on the closing brace, since it's going in bytecode
order and will thus discover the `Return` at offset 38 first (matching
the source position 30 it's currently looking for) and setting the
breakpoint there. This `Return` bytecode however is only executed when
the generator is resumed via `GeneratorPrototype.return()`, and it'll
not hit when the developer uses the generator normally, which is not
the desired behavior and extremely confusing (especially since stepping
on the other hand works as expected).
With this patch, we no longer slap a source position (and in particular
not the function literal's return position) onto these internal
`Return`s as you can see from the generated bytecode below:
```
0 : SwitchOnGeneratorState r0, [0], [1] { 0: @20 }
4 : Mov <closure>, r2
7 : Mov <this>, r3
13 E> 10 : InvokeIntrinsic [_CreateJSGeneratorObject], r2-r3
14 : Star0
13 E> 15 : SuspendGenerator r0, r0-r1, [0]
20 : ResumeGenerator r0, r0-r1
24 : Star2
25 : InvokeIntrinsic [_GeneratorGetResumeMode], r0-r0
29 : SwitchOnSmiNoFeedback [1], [2], [0] { 0: @39, 1: @36 }
33 : Ldar r2
13 E> 35 : Throw
36 : Ldar r2
38 : Return
27 S> 39 : LdaSmi [1]
41 : Star1
42 : LdaUndefined
30 S> 43 : Return
```
This also allows us to remove the break position finding hack that was
kept in BreakIterator::BreakIndexFromPosition() for generators and
modules.
Fixed: chromium:901819
Change-Id: If19a6b26e2622d49b6b5e54bf7a162747543f970
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2727820
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73119}
This is a reland of cf93071c91
Original change's description:
> [interpreter] Short Star bytecode
>
> Design doc:
> https://docs.google.com/document/d/1g_NExMT78II_KnIYNa9MvyPYIj23qAiFUEsyemY5KRk/edit
>
> This change adds 16 new interpreter opcodes, kStar0 through kStar15, so
> that we can use a single byte to represent the common operation of
> storing to a low-numbered register. This generally reduces the quantity
> of bytecode generated on web sites by 8-9%.
>
> In order to not degrade speed, a couple of other changes are required:
>
> The existing lookahead logic to check for Star after certain other
> bytecode handlers is updated to check for these new short Star codes
> instead. Furthermore, that lookahead logic is updated to contain its own
> copy of the dispatch jump rather than merging control flow with the
> lookahead-failed case, to improve branch prediction.
>
> A bunch of constants use bytecode size in bytes as a proxy for the size
> or complexity of a function, and are adjusted downward proportionally to
> the decrease in generated bytecode size.
>
> Other small drive-by fix: update generate-bytecode-expectations to emit
> \n instead of \r\n on Windows.
>
> Change-Id: I6307c2b0f5794a3a1088bb0fb94f6e1615441ed5
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2641180
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
> Cr-Commit-Position: refs/heads/master@{#72773}
Change-Id: I1afb670c25694498b3989de615858f984a8c7f6f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2698057
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72821}
This reverts commit cf93071c91.
Reason for revert: Speculative revert because of Mac4 GC stress failure: https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Mac64%20GC%20Stress/16697/overview
Original change's description:
> [interpreter] Short Star bytecode
>
> Design doc:
> https://docs.google.com/document/d/1g_NExMT78II_KnIYNa9MvyPYIj23qAiFUEsyemY5KRk/edit
>
> This change adds 16 new interpreter opcodes, kStar0 through kStar15, so
> that we can use a single byte to represent the common operation of
> storing to a low-numbered register. This generally reduces the quantity
> of bytecode generated on web sites by 8-9%.
>
> In order to not degrade speed, a couple of other changes are required:
>
> The existing lookahead logic to check for Star after certain other
> bytecode handlers is updated to check for these new short Star codes
> instead. Furthermore, that lookahead logic is updated to contain its own
> copy of the dispatch jump rather than merging control flow with the
> lookahead-failed case, to improve branch prediction.
>
> A bunch of constants use bytecode size in bytes as a proxy for the size
> or complexity of a function, and are adjusted downward proportionally to
> the decrease in generated bytecode size.
>
> Other small drive-by fix: update generate-bytecode-expectations to emit
> \n instead of \r\n on Windows.
>
> Change-Id: I6307c2b0f5794a3a1088bb0fb94f6e1615441ed5
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2641180
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
> Cr-Commit-Position: refs/heads/master@{#72773}
TBR=rmcilroy@chromium.org,mythria@chromium.org,seth.brenith@microsoft.com
Change-Id: I0162b9400861b90bacef27cca9aebc8ab9d74c10
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2697350
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72777}
Design doc:
https://docs.google.com/document/d/1g_NExMT78II_KnIYNa9MvyPYIj23qAiFUEsyemY5KRk/edit
This change adds 16 new interpreter opcodes, kStar0 through kStar15, so
that we can use a single byte to represent the common operation of
storing to a low-numbered register. This generally reduces the quantity
of bytecode generated on web sites by 8-9%.
In order to not degrade speed, a couple of other changes are required:
The existing lookahead logic to check for Star after certain other
bytecode handlers is updated to check for these new short Star codes
instead. Furthermore, that lookahead logic is updated to contain its own
copy of the dispatch jump rather than merging control flow with the
lookahead-failed case, to improve branch prediction.
A bunch of constants use bytecode size in bytes as a proxy for the size
or complexity of a function, and are adjusted downward proportionally to
the decrease in generated bytecode size.
Other small drive-by fix: update generate-bytecode-expectations to emit
\n instead of \r\n on Windows.
Change-Id: I6307c2b0f5794a3a1088bb0fb94f6e1615441ed5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2641180
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#72773}
Since now the IterationBody StackChecks are implicit within JumpLoops,
we are able to eagerly deopt in them. If we do that, whenever we advance
to the next bytecode we don't have to advance to the next literal
bytecode, but instead "advance" in the sense of doing the JumpLoop.
Adding tests that test this advancing for wide and extra wide JumpLoops.
Also, marking JumpLoop as needing source positions since now it has
the ability of causing an interrupt.
Bug: v8:10149, v8:9960
Fixes: v8:10149
Change-Id: Ib0d9efdfb379e0dfbba7a7f67cba9262668813b0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2064226
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66809}
This CL is a step towards making StackChecks implicit. In a follow-up CL
said StackChecks will become implicit within JumpLoops.
Cq-Include-Trybots: luci.chromium.try:linux-rel
Bug: v8:10149, v8:9960
Change-Id: I5ae247be3f7a58ccdf86398cace30724715767a8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2062391
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66668}
FunctionEntry StackChecks is one of the two cases where we generate a
StackCheck bytecode. In these cases, we do stack check against the js
limit (not to be confused with the real js limit). Their purpose is to
be able to interrupt the running code.
We can omit the FunctionEntry StackCheck by embedding its code into
the InterpreterEntryTrampoline builtin. We save one bytecode per
interpreted function.
This change has rippling effects for optimized code, as well as the
deoptimizer.
Bug: v8:10149, v8:9977, v8:9960
Change-Id: I6156de48b3bc0b519dd21190a8e6214fbe96c78d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1914218
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66206}
The function-entry stack check should dominate all other
instructions in a function. Prior to this CL it was possible to create
paths not including a stack check due to SwitchOnGeneratorState: the
generator-creation branch had a stack check, while generator-resume
branches did not.
0 : af fb 00 01 SwitchOnGeneratorState r0, [0], [1] { 0: @22 }
4 : 27 fe fa Mov <closure>, r1
7 : 27 02 f9 Mov <this>, r2
10 : 64 0a fa 02 InvokeIntrinsic [_CreateJSGeneratorObject], r1-r2
14 : 26 fb Star r0
16 : a7 StackCheck
17 : b0 fb fb 01 00 SuspendGenerator r0, r0-r0, [0]
22 : b1 fb fb 01 ResumeGenerator r0, r0-r0
[... no stack check here ...]
This CL moves the stack check to the beginning of the bytecode array,
i.e. before SwitchOnGeneratorState.
Bug: chromium:1020031
Change-Id: I8ba8cba99611ddbe50c76023129d926cc84b1d5e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1903440
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64888}
Original change's description:
> [runtime] Remove extension slots from context objects
>
> Context objects have an extension slot, which contains further
> additional data that depends on the type of the context.
>
> This CL removes the extension slot from contexts that don't need
> them, hence reducing memory.
>
> The following contexts will still have an extension slot: native,
> module, await, block and with contexts. See objects/contexts.h for
> what the slot is used for.
> The following contexts will not have an extension slot anymore (they
> were not used before): script, catch and builtin contexts.
> Eval and function contexts only have the extension slot if they
> contain a sloppy eval.
>
> Bug: v8:9744
> Change-Id: I8ca56c22fa02437bbac392ea72174ebfca80e030
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1863191
> Commit-Queue: Victor Gomes <victorgomes@google.com>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> Auto-Submit: Victor Gomes <victorgomes@google.com>
> Cr-Commit-Position: refs/heads/master@{#64372}
TBR=verwaest@chromium.org,jgruber@chromium.org,ulan@chromium.org,leszeks@chromium.org,petermarshall@chromium.org
Bug: v8:9744
Change-Id: I8700ed2fa62c89e86c39bb16ac3167f38ea8d63f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1873695
Commit-Queue: Victor Gomes <victorgomes@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64477}
This is a reland of c48096d442
Original change's description:
> Reland "[runtime] Remove extension slots from context objects"
>
> This is a reland of c07c02e1c4
>
> Original change's description:
> > [runtime] Remove extension slots from context objects
> >
> > Context objects have an extension slot, which contains further
> > additional data that depends on the type of the context.
> >
> > This CL removes the extension slot from contexts that don't need
> > them, hence reducing memory.
> >
> > The following contexts will still have an extension slot: native,
> > module, await, block and with contexts. See objects/contexts.h for
> > what the slot is used for.
> > The following contexts will not have an extension slot anymore (they
> > were not used before): script, catch and builtin contexts.
> > Eval and function contexts only have the extension slot if they
> > contain a sloppy eval.
> >
> > Bug: v8:9744
> > Change-Id: I8ca56c22fa02437bbac392ea72174ebfca80e030
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1863191
> > Commit-Queue: Victor Gomes <victorgomes@google.com>
> > Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> > Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> > Auto-Submit: Victor Gomes <victorgomes@google.com>
> > Cr-Commit-Position: refs/heads/master@{#64372}
>
> TBR=verwaest@chromium.org,jgruber@chromium.org,ulan@chromium.org,leszeks@chromium.org,petermarshall@chromium.org
>
> Bug: v8:9744
> Change-Id: I0749cc2d8f59940c25841736634a70047116d647
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1869192
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Commit-Queue: Peter Marshall <petermarshall@chromium.org>
> Auto-Submit: Victor Gomes <victorgomes@google.com>
> Cr-Commit-Position: refs/heads/master@{#64380}
TBR=verwaest@chromium.org,jgruber@chromium.org,ulan@chromium.org,leszeks@chromium.org,petermarshall@chromium.org
Bug: v8:9744
Change-Id: I621ffe98722f8c4defaf277b8d1666484ba2963f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1872400
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Victor Gomes <victorgomes@google.com>
Cr-Commit-Position: refs/heads/master@{#64451}
This reverts commit c48096d442.
Reason for revert: Flaky bot failures (https://bugs.chromium.org/p/v8/issues/detail?id=9744#c9)
Original change's description:
> Reland "[runtime] Remove extension slots from context objects"
>
> This is a reland of c07c02e1c4
>
> Original change's description:
> > [runtime] Remove extension slots from context objects
> >
> > Context objects have an extension slot, which contains further
> > additional data that depends on the type of the context.
> >
> > This CL removes the extension slot from contexts that don't need
> > them, hence reducing memory.
> >
> > The following contexts will still have an extension slot: native,
> > module, await, block and with contexts. See objects/contexts.h for
> > what the slot is used for.
> > The following contexts will not have an extension slot anymore (they
> > were not used before): script, catch and builtin contexts.
> > Eval and function contexts only have the extension slot if they
> > contain a sloppy eval.
> >
> > Bug: v8:9744
> > Change-Id: I8ca56c22fa02437bbac392ea72174ebfca80e030
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1863191
> > Commit-Queue: Victor Gomes <victorgomes@google.com>
> > Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> > Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> > Auto-Submit: Victor Gomes <victorgomes@google.com>
> > Cr-Commit-Position: refs/heads/master@{#64372}
>
> TBR=verwaest@chromium.org,jgruber@chromium.org,ulan@chromium.org,leszeks@chromium.org,petermarshall@chromium.org
>
> Bug: v8:9744
> Change-Id: I0749cc2d8f59940c25841736634a70047116d647
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1869192
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Commit-Queue: Peter Marshall <petermarshall@chromium.org>
> Auto-Submit: Victor Gomes <victorgomes@google.com>
> Cr-Commit-Position: refs/heads/master@{#64380}
TBR=ulan@chromium.org,jgruber@chromium.org,petermarshall@chromium.org,leszeks@chromium.org,verwaest@chromium.org,victorgomes@google.com
# Not skipping CQ checks because original CL landed > 1 day ago.
Bug: v8:9744
Change-Id: Ia58067b41f1eb5880a52b36ead754d7190ff7f6f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1871922
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64424}
This is a reland of c07c02e1c4
Original change's description:
> [runtime] Remove extension slots from context objects
>
> Context objects have an extension slot, which contains further
> additional data that depends on the type of the context.
>
> This CL removes the extension slot from contexts that don't need
> them, hence reducing memory.
>
> The following contexts will still have an extension slot: native,
> module, await, block and with contexts. See objects/contexts.h for
> what the slot is used for.
> The following contexts will not have an extension slot anymore (they
> were not used before): script, catch and builtin contexts.
> Eval and function contexts only have the extension slot if they
> contain a sloppy eval.
>
> Bug: v8:9744
> Change-Id: I8ca56c22fa02437bbac392ea72174ebfca80e030
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1863191
> Commit-Queue: Victor Gomes <victorgomes@google.com>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> Auto-Submit: Victor Gomes <victorgomes@google.com>
> Cr-Commit-Position: refs/heads/master@{#64372}
TBR=verwaest@chromium.org,jgruber@chromium.org,ulan@chromium.org,leszeks@chromium.org,petermarshall@chromium.org
Bug: v8:9744
Change-Id: I0749cc2d8f59940c25841736634a70047116d647
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1869192
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Auto-Submit: Victor Gomes <victorgomes@google.com>
Cr-Commit-Position: refs/heads/master@{#64380}
This reverts commit c07c02e1c4.
Reason for revert: MSAN failures:
https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20-%20arm64%20-%20sim%20-%20MSAN/29251
Original change's description:
> [runtime] Remove extension slots from context objects
>
> Context objects have an extension slot, which contains further
> additional data that depends on the type of the context.
>
> This CL removes the extension slot from contexts that don't need
> them, hence reducing memory.
>
> The following contexts will still have an extension slot: native,
> module, await, block and with contexts. See objects/contexts.h for
> what the slot is used for.
> The following contexts will not have an extension slot anymore (they
> were not used before): script, catch and builtin contexts.
> Eval and function contexts only have the extension slot if they
> contain a sloppy eval.
>
> Bug: v8:9744
> Change-Id: I8ca56c22fa02437bbac392ea72174ebfca80e030
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1863191
> Commit-Queue: Victor Gomes <victorgomes@google.com>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> Auto-Submit: Victor Gomes <victorgomes@google.com>
> Cr-Commit-Position: refs/heads/master@{#64372}
TBR=ulan@chromium.org,jgruber@chromium.org,petermarshall@chromium.org,leszeks@chromium.org,verwaest@chromium.org,victorgomes@google.com
Change-Id: I98dee04ab4d3ae977053982ec884b738d2f6f623
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:9744
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1868611
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64373}
Context objects have an extension slot, which contains further
additional data that depends on the type of the context.
This CL removes the extension slot from contexts that don't need
them, hence reducing memory.
The following contexts will still have an extension slot: native,
module, await, block and with contexts. See objects/contexts.h for
what the slot is used for.
The following contexts will not have an extension slot anymore (they
were not used before): script, catch and builtin contexts.
Eval and function contexts only have the extension slot if they
contain a sloppy eval.
Bug: v8:9744
Change-Id: I8ca56c22fa02437bbac392ea72174ebfca80e030
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1863191
Commit-Queue: Victor Gomes <victorgomes@google.com>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Auto-Submit: Victor Gomes <victorgomes@google.com>
Cr-Commit-Position: refs/heads/master@{#64372}
This is a reland of c7c47c68f2.
This makes TSAN happy in addition to:
Previously I presumed that the context read from a frame in the profiler was
a valid context. Turns out that on non-intel we're not guaranteed that the
frame is properly set up. In the case we looked at, the profiler took a
sample right before writing the frame marker indicating a builtin frame,
causing the "context" pointer from that frame to be a bytecode array. Since
we'll read random garbage on the stack as a possible context pointer, I made
the code reading the native context from it a little more defensive.
Bug: v8:9860
Tbr: ulan@chromium.org, neis@chromium.org, ishell@chromium.org
Original change's description:
> [runtime] Move Context::native_context to the map
>
> Remove the native context slot from contexts by making context maps
> native-context-specific. Now we require 2 loads to go from a context to the
> native context, but we have 1 field fewer to store when creating contexts.
>
> Change-Id: I3c0d7c50c94060c4129db684f46a567de6f30e8d
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1859629
> Commit-Queue: Toon Verwaest <verwaest@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> Reviewed-by: Maya Lekova <mslekova@chromium.org>
> Reviewed-by: Georg Neis <neis@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#64296}
Change-Id: I4d0ab4cbbb23a9ae616407f17ef8f35a0b68ddb4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1864654
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64360}
This reverts commit c7c47c68f2.
Reason for revert: breaks TSAN
https://ci.chromium.org/p/v8/builders/ci/V8%20Linux64%20TSAN/28738
Original change's description:
> Reland "[runtime] Move Context::native_context to the map"
>
> This is a reland of f05bae1e0d
>
> Previously I presumed that the context read from a frame in the profiler was
> a valid context. Turns out that on non-intel we're not guaranteed that the
> frame is properly set up. In the case we looked at, the profiler took a
> sample right before writing the frame marker indicating a builtin frame,
> causing the "context" pointer from that frame to be a bytecode array. Since
> we'll read random garbage on the stack as a possible context pointer, I made
> the code reading the native context from it a little more defensive.
>
> Bug: v8:9860
>
> Original change's description:
> > [runtime] Move Context::native_context to the map
> >
> > Remove the native context slot from contexts by making context maps
> > native-context-specific. Now we require 2 loads to go from a context to the
> > native context, but we have 1 field fewer to store when creating contexts.
> >
> > Change-Id: I3c0d7c50c94060c4129db684f46a567de6f30e8d
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1859629
> > Commit-Queue: Toon Verwaest <verwaest@chromium.org>
> > Reviewed-by: Igor Sheludko <ishell@chromium.org>
> > Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> > Reviewed-by: Maya Lekova <mslekova@chromium.org>
> > Reviewed-by: Georg Neis <neis@chromium.org>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#64296}
>
> Change-Id: If9461e9b21d35a260d71c79d7f95e518cc429e09
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1864930
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Georg Neis <neis@chromium.org>
> Commit-Queue: Toon Verwaest <verwaest@chromium.org>
> Auto-Submit: Toon Verwaest <verwaest@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#64314}
TBR=ulan@chromium.org,neis@chromium.org,petermarshall@chromium.org,ishell@chromium.org,verwaest@chromium.org,mslekova@chromium.org,victorgomes@google.com
Change-Id: I4f9edc62ea6f9f5857619ff0ad1a63cab4b33cc3
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:9860
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1864937
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64316}
This is a reland of f05bae1e0d
Previously I presumed that the context read from a frame in the profiler was
a valid context. Turns out that on non-intel we're not guaranteed that the
frame is properly set up. In the case we looked at, the profiler took a
sample right before writing the frame marker indicating a builtin frame,
causing the "context" pointer from that frame to be a bytecode array. Since
we'll read random garbage on the stack as a possible context pointer, I made
the code reading the native context from it a little more defensive.
Bug: v8:9860
Original change's description:
> [runtime] Move Context::native_context to the map
>
> Remove the native context slot from contexts by making context maps
> native-context-specific. Now we require 2 loads to go from a context to the
> native context, but we have 1 field fewer to store when creating contexts.
>
> Change-Id: I3c0d7c50c94060c4129db684f46a567de6f30e8d
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1859629
> Commit-Queue: Toon Verwaest <verwaest@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> Reviewed-by: Maya Lekova <mslekova@chromium.org>
> Reviewed-by: Georg Neis <neis@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#64296}
Change-Id: If9461e9b21d35a260d71c79d7f95e518cc429e09
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1864930
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Auto-Submit: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64314}
This reverts commit f05bae1e0d.
Reason for revert: broke arm sim debug
https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20-%20arm64%20-%20sim%20-%20debug/17714https://logs.chromium.org/logs/v8/buildbucket/cr-buildbucket.appspot.com/8899519852984476944/+/steps/Check_-_trusted/0/logs/FunctionDetailsInlining/0
Original change's description:
> [runtime] Move Context::native_context to the map
>
> Remove the native context slot from contexts by making context maps
> native-context-specific. Now we require 2 loads to go from a context to the
> native context, but we have 1 field fewer to store when creating contexts.
>
> Change-Id: I3c0d7c50c94060c4129db684f46a567de6f30e8d
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1859629
> Commit-Queue: Toon Verwaest <verwaest@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> Reviewed-by: Maya Lekova <mslekova@chromium.org>
> Reviewed-by: Georg Neis <neis@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#64296}
TBR=ulan@chromium.org,neis@chromium.org,petermarshall@chromium.org,ishell@chromium.org,verwaest@chromium.org,mslekova@chromium.org,victorgomes@google.com
Change-Id: Ie7b4086c3a9ab2627ecac599da36b20cf8d1f948
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1863200
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64299}
Remove the native context slot from contexts by making context maps
native-context-specific. Now we require 2 loads to go from a context to the
native context, but we have 1 field fewer to store when creating contexts.
Change-Id: I3c0d7c50c94060c4129db684f46a567de6f30e8d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1859629
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64296}
This is a reland of 1fba044154
Chromium expectation tests have been disabled, and will be enabled
Original change's description:
> [destructuring] Elide coercible check for simple keys
>
> Simple object destructuring, such as `let {a,b} = o`, is less efficient
> than the equivalent assignments `let a = o.a; let b = o.b`. This is
> because it does a nil check of `o` before the assignments. However, this
> nil check is not strictly necessary for simple (i.e. non-computed) names,
> as there will be an equivalent nil check on the first access to o in
> `o.a`. For computed names the computation is unfortunately obervable.
>
> So, we can elide the nil check when the first property (if any) of the
> destructuring target is a non-computed name. This messes a bit with our
> error messages, so we re-use the CallPrinter to also find destructuring
> assignment based errors, and fiddle with the error message there. As
> a side-effect, we also get out the object name in the AST, so we can
> output a slightly nicer error message.
>
> Change-Id: Iafa858e27ed771a146cd3ba57903cc73bb46951d
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1773254
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#63453}
TBR=verwaest@chromium.org
Bug: chromium:999473
Change-Id: Ib0b2e4be433c50521ba1722e1c06b672bfefa405
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1777702
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63477}
This reverts commit 1fba044154.
Reason for revert: blocks V8 roll due to layout test failures caused by error message changes:
https://ci.chromium.org/p/v8/builders/ci/V8%20Blink%20Linux/347
Original change's description:
> [destructuring] Elide coercible check for simple keys
>
> Simple object destructuring, such as `let {a,b} = o`, is less efficient
> than the equivalent assignments `let a = o.a; let b = o.b`. This is
> because it does a nil check of `o` before the assignments. However, this
> nil check is not strictly necessary for simple (i.e. non-computed) names,
> as there will be an equivalent nil check on the first access to o in
> `o.a`. For computed names the computation is unfortunately obervable.
>
> So, we can elide the nil check when the first property (if any) of the
> destructuring target is a non-computed name. This messes a bit with our
> error messages, so we re-use the CallPrinter to also find destructuring
> assignment based errors, and fiddle with the error message there. As
> a side-effect, we also get out the object name in the AST, so we can
> output a slightly nicer error message.
>
> Change-Id: Iafa858e27ed771a146cd3ba57903cc73bb46951d
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1773254
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#63453}
TBR=leszeks@chromium.org,verwaest@chromium.org
Change-Id: I74cf06ebd987e5b8bbe1831b0042c085edf37f5b
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1776994
Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63465}
Simple object destructuring, such as `let {a,b} = o`, is less efficient
than the equivalent assignments `let a = o.a; let b = o.b`. This is
because it does a nil check of `o` before the assignments. However, this
nil check is not strictly necessary for simple (i.e. non-computed) names,
as there will be an equivalent nil check on the first access to o in
`o.a`. For computed names the computation is unfortunately obervable.
So, we can elide the nil check when the first property (if any) of the
destructuring target is a non-computed name. This messes a bit with our
error messages, so we re-use the CallPrinter to also find destructuring
assignment based errors, and fiddle with the error message there. As
a side-effect, we also get out the object name in the AST, so we can
output a slightly nicer error message.
Change-Id: Iafa858e27ed771a146cd3ba57903cc73bb46951d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1773254
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63453}
This is a pre-work for allocating feedback vectors lazily. Feedback cells
are required to share the feedback vectors across the different closures
of the same function. Currently, they are held in the CreateClosureSlot
in the feedback vector. With lazy feedback vector allocation, we may not
have a feedback vector. However, we still need a place to store the
feedback cells, so if feedback vector is allocated in future it can still
be shared across closures.
Here is the detailed design doc:
https://docs.google.com/document/d/1m2PTNChrlJqw9MiwK_xEJfqbFHAgEHmgGqmIN49PaBY/edit
BUG=v8:8394
Change-Id: Ib406d862b2809b1293bfecdcfcf8dea3127cb1c7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1503753
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60147}
This is a reland of 35269f77f8
Switches on an expression that unconditionally throws would have all their
case statements dead, causing a DCHECK error in the SwitchBuilder. This
fixes up the DCHECK to allow dead labels.
Original change's description:
> [ignition] Skip binding dead labels
>
> BytecodeLabels for forward jumps may create a dead basic block if their
> corresponding jump was elided (due to it dead code elimination). We can
> avoid generating such dead basic blocks by skipping the label bind when
> no corresponding jump has been observed. This works because all jumps
> except JumpLoop are forward jumps, so we only have to special case one
> Bind for loop headers to bind unconditionally.
>
> Since Binds are now conditional on a jump existing, we can no longer rely
> on using Bind to get the current offset (e.g. at the beginning of a try
> block). Instead, we now expose the current offset in the bytecode array
> writer. Conveniently, this means that we can be a bit smarter about basic
> blocks around these statements.
>
> As a drive-by, remove the unused Bind(target,label) function.
>
> Bug: chromium:934166
> Change-Id: I532aa452fb083560d07b90da99caca0b1d082aa3
> Reviewed-on: https://chromium-review.googlesource.com/c/1488763
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#59942}
TBR=rmcilroy@chromium.org
Bug: chromium:934166
Change-Id: If6eab4162106717ce64a2dc477000c6a76354cb4
Reviewed-on: https://chromium-review.googlesource.com/c/1494535
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59948}
This reverts commit 35269f77f8.
Reason for revert: Fuzzer unhappy: https://ci.chromium.org/p/v8/builders/ci/V8%20Fuzzer/29792
Original change's description:
> [ignition] Skip binding dead labels
>
> BytecodeLabels for forward jumps may create a dead basic block if their
> corresponding jump was elided (due to it dead code elimination). We can
> avoid generating such dead basic blocks by skipping the label bind when
> no corresponding jump has been observed. This works because all jumps
> except JumpLoop are forward jumps, so we only have to special case one
> Bind for loop headers to bind unconditionally.
>
> Since Binds are now conditional on a jump existing, we can no longer rely
> on using Bind to get the current offset (e.g. at the beginning of a try
> block). Instead, we now expose the current offset in the bytecode array
> writer. Conveniently, this means that we can be a bit smarter about basic
> blocks around these statements.
>
> As a drive-by, remove the unused Bind(target,label) function.
>
> Bug: chromium:934166
> Change-Id: I532aa452fb083560d07b90da99caca0b1d082aa3
> Reviewed-on: https://chromium-review.googlesource.com/c/1488763
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#59942}
TBR=rmcilroy@chromium.org,leszeks@chromium.org
Change-Id: I8118e54e0afa5e08b0a0a874c952f8a01f1c3242
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:934166
Reviewed-on: https://chromium-review.googlesource.com/c/1494534
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59947}
BytecodeLabels for forward jumps may create a dead basic block if their
corresponding jump was elided (due to it dead code elimination). We can
avoid generating such dead basic blocks by skipping the label bind when
no corresponding jump has been observed. This works because all jumps
except JumpLoop are forward jumps, so we only have to special case one
Bind for loop headers to bind unconditionally.
Since Binds are now conditional on a jump existing, we can no longer rely
on using Bind to get the current offset (e.g. at the beginning of a try
block). Instead, we now expose the current offset in the bytecode array
writer. Conveniently, this means that we can be a bit smarter about basic
blocks around these statements.
As a drive-by, remove the unused Bind(target,label) function.
Bug: chromium:934166
Change-Id: I532aa452fb083560d07b90da99caca0b1d082aa3
Reviewed-on: https://chromium-review.googlesource.com/c/1488763
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59942}
For desrtucturing assignments from null/undefined, we throw an error
that references the destructuring object literal's property name, e.g.
for
var { x } = null;
we report that we cannot destructure 'x' from null.
Rather than calculating this property during bytecode generation (and
including it in the bytecode as an argument to the type error
constructor), we can calculate it at exception throwing time, by
re-parsing the source in a similar way to the existing call site
rendering.
This slightly decreases bytecode size and slightly decreases the amount
of work the bytecode compiler needs to do. In the future, it could also
allow us to give more detailed error messages, as we now have access to
the entire AST and are on the slow path anyway.
Bug: v8:6499
Change-Id: Icdbd4667db548b4e5e62ef97797a3771b5c1bf72
Reviewed-on: https://chromium-review.googlesource.com/c/1396080
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58706}
Emit a single destructuring assignment for destructuring declarations,
which can be desugared by the bytecode generator. This allows us to
remove destructuring desugaring from the parser (specifically, the
pattern rewriter) entirely.
The pattern "rewriter" is now only responsible for walking the
destructuring pattern to declare variables, mark them assigned, and
potentially rewrite scopes for the edge case of parameters with a sloppy
eval.
Note that since the rewriter is no longer rewriting, we have to flip the
VariableProxy copying logic for var re-lookup, so that we now pass the
new VariableProxy to the variable declaration and leave the original
unresolved (rather than passing the original through and rewriting to a
new unresolved VariableProxy).
This change does have some effect on breakpoint locations, due to some
of the available information changing between the parser and bytecode
generator, however the new locations appear to be more consistent
between assignments and declarations.
Change-Id: I3a58dd0a387d2bfb8e5e9e22dde0acc5f440cb82
Reviewed-on: https://chromium-review.googlesource.com/c/1382462
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58670}
This patch changes the output from:
function fn() {
^
SyntaxError: Unexpected end of input
to:
function fn() {
^
SyntaxError: missing '}' after function body
Bug: v8:6513, v8:7321
Change-Id: I4ca8a40fa0be246da2a3ff776b3fb3c87b4ba4e0
Also-By: gsathya@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/c/1367448
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58116}
As opposed to the register.
For subtle reasons, this fixes a deoptimizer bug with handling return
values in lazy deopt. Since the return values can now only overwrite
the accumulator, there is no danger of overwriting a captured object
that might be later used (since there is no "later").
Bug: chromium:902608
Change-Id: I3a7a10bb1c7a6f4303a01d60f80680afcb7bc942
Reviewed-on: https://chromium-review.googlesource.com/c/1325901
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57349}
Change the way we start collecting async stack traces by storing the
current microtask as a root instead of trying to make sense of the
last frame we see. This makes it possible to use the zero cost async
stack traces in Node.js as well (where the last JavaScript frame we
see is not the actual async function, but some frame related to the
main event loop usually).
In addition to the benefit that it now works with Node.js, we can also
extend the new machinery to look through (almost arbitrary) promise
chains. For example this code snippet
```js
(async function() {
await Promise.resolve().then(() =>
console.log(new Error().stack));
})();
```
can be made to also show the async function frame, even though at the
point where the stack trace is collected we don't have any async
function on the stack. But instead there's a PromiseReactionJobTask
as "current microtask", and we can dig into the chained promise to
see where the async execution is going to continue and eventually
find the await promise in the chain.
This also removes the removes the need to allocate `.generator_object`
specially during scope resolution.
Bug: v8:7522
Ref: nodejs/node#11865
Tbr: ulan@chromium.org
Design-Document: bit.ly/v8-zero-cost-async-stack-traces
Change-Id: Ib96cb17c2f75cce083a24e5ba2bbb7914e20d203
Reviewed-on: https://chromium-review.googlesource.com/c/1277505
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56590}
This JSAsyncFunctionObject represents the implicit generator object
inside of async functions, and also holds the outer promise for the
async functions. This in turn allows us to get rid of the .promise
in the Parser / BytecodeGenerator completely, and will make it
possible to build zero-cost async stack traces independent of the
concrete synchronous part of the stack frame (which currently breaks
in Node.js).
In the bytecode all the async function operations now take this new
JSAsyncFunctionObject instead of passing both the .generator_object
and the .promise, which further simplifies and shrinks the bytecode.
It also reduces the size of async function frames, potentially making
the suspend/resume cheaper.
This also changes `await` to use intrinsics instead of calling to
special JSFunctions on the native context, and thus reduces the size of
the native contexts.
Drive-by-fix: Introduce a dedicated JSCreateAsyncFunctionObject operator
to TurboFan.
Bug: v8:7253, v8:7522
Change-Id: I2305302285156aa1f71328ecac70377abdd92c80
Ref: nodejs/node#11865
Design-Document: http://bit.ly/v8-zero-cost-async-stack-traces
Reviewed-on: https://chromium-review.googlesource.com/c/1273049
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56554}
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: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56502}
The Parser desugaring didn't use the AsyncReturnStatement consistently
to return from async functions (aka resolve the .promise with the return
value and return the .promise from the async function). Instead the
Parser essentially had a copy of the BytecodeGenerator functionality.
This change unifies the handling of returns from async functions.
Bug: v8:7522, v8:8238
Change-Id: Ib00a60aee30d541b84835d9cc83e9937b7a39e26
Reviewed-on: https://chromium-review.googlesource.com/c/1269036
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56453}
This introduces a new flag --async-stack-traces, which enables zero-cost
async stack traces. This enriches the non-standard Error.stack property
with async stack frames computed from walking up the promise chains and
collecting all the await suspension points along the way. In Error.stack
these async frames are marked with "async" to make it possible to
distinguish them from regular frames, for example:
```
Error: Some error message
at bar (<anonymous>)
at async foo (<anonymous>)
```
It's zero-cost because no additional information is collected during the
execution of the program, but only the information already present in the
promise chains is used to reconstruct an approximation of the async stack
in case of an exception. But this approximation is limited to suspension
points at await's in async functions. This depends on a recent ECMAScript
specification change, flagged behind --harmony-await-optimization and
implied the --async-stack-traces flag. Without this change there's no
way to get from the outer promise of an async function to the rest of
the promise chain, since the link is broken by the indirection introduced
by await.
For async functions the special outer promise, named .promise in the
Parser desugaring, is now forcible allocated to stack slot 0 during
scope resolution, to make it accessible to the stack frame construction
logic. Note that this first prototype doesn't yet work fully support
async generators and might have other limitations.
Bug: v8:7522
Ref: nodejs/node#11865
Change-Id: I0cc8e3cdfe45dab56d3d506be2d25907409b01a9
Design-Document: http://bit.ly/v8-zero-cost-async-stack-traces
Reviewed-on: https://chromium-review.googlesource.com/c/1256762
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56363}
* Rename BoilerplateDescription to ObjectBoilerplateDescription
* Add literal_type flag to ObjectBoilerplateDescription,
which is stored as zeroth element of Fixed array
* Create ArrayBoilerplateDescription with elements_kind and
constant_elements field
* Replace CompileTimeValue and ConstantElementPair with
ArrayBoilerplateDescription
* Kill ConstantElementPair and CompileTimeValue
Change-Id: Icb42dcfd575a27e2b64ffd5e2e61f9d703d5e986
Bug: v8:7787, chromium:818642
Reviewed-on: https://chromium-review.googlesource.com/1122411
Commit-Queue: Chandan Reddy <chandanreddy@google.com>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54272}
New intstrumentation consists of:
- kAsyncFunctionSuspended when async function is suspended on await
(called on each await),
- kAsyncFunctionFinished when async function is finished.
Old instrumentation was based on reusing async function promise.
Using this promise produces couple side effects:
- for any promise instrumentation we first need to check if it is
special case for async function promise or not - it requires
expensive reading from promise object.
- we capture stack for async functions even if it does not contain
awaits.
- we do not properly cancel async task created for async function.
New intsrumntation resolved all these problems as well as provide
clear mapping between async task and generator which we can use later
to fetch scope information for async functions on pause.
R=dgozman@chromium.org,yangguo@chromium.org
Bug: v8:7078
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
Change-Id: Ifdcec947d91e6e3d4d5f9029bc080a19b8e23d41
Reviewed-on: https://chromium-review.googlesource.com/1043096
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53445}
https://github.com/tc39/proposal-intl-locale
Rename locale property to baseName to better reflect the intented use case and the change in spec.
TBR: bmeurer@chromium.org
Bug: v8:7684
Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
Change-Id: I91b630b49ce73abcebd6040ec968c91d75cff879
Reviewed-on: https://chromium-review.googlesource.com/1014411
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53193}
Instead rely on the scope info containing the name as well.
Change-Id: Ie1f96ea023a793b11209510566f6831b1dfd40ab
Reviewed-on: https://chromium-review.googlesource.com/1042567
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52983}
There are likely cleanups that can be done after this CL:
- context-related functions in the interpreter and compiler take ScopeInfo as
well as ScopeType and slot-count as input. The latter 2 should be directly
derived from the former. We should be able to drop FunctionContextParameters.
- ContextExtension is probably not needed anymore, since we now always have the
correct scope_info directly in the SCOPE_INFO_INDEX slot.
Bug: v8:7066
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: Ie1f6134c686a9f2183e54730d9cdd598a9e5ab67
Reviewed-on: https://chromium-review.googlesource.com/785151
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52952}
Several functions on Array.prototype incorrectly threw a TypeError just
because their receiver was sealed or frozen.
Bug: v8:7677
Change-Id: I4ec38bfbf468f9bd676f1c0b341c8a50cf814f15
Reviewed-on: https://chromium-review.googlesource.com/1021870
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52718}
There are various situations where we explicitly compare a SMI against
another SMI (e.g., BuildIndexedJump). This is also a common pattern for
generated code (e.g., comparing a loop variable with an integer). Instead
of using the generic equality/strict-equality stub for this, which is
expensive, this CL offers a simple comparison stub, repurposing the
TestEqualStrictNoFeedback bytecode to TestReferenceEqual
Bug: v8:5310
Change-Id: Ib2b47cd24d5386cf0d20d3bd794776dc6e3a02a5
Reviewed-on: https://chromium-review.googlesource.com/1007542
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Christian O. Andersson <cricke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52655}
