This is a reland of part of
https://chromium-review.googlesource.com/c/v8/v8/+/1397664.
It drops the explicit fni_.Infer() call after parsing arrow functions. We'll
want to avoid inferring if the arrow function is an argument to a function
call.
It also avoids adding the single argument of "name => " to the inferred name.
Bug: chromium:916975
Change-Id: I96a934408113483d73eba14073fe21e8cfe2ada6
Reviewed-on: https://chromium-review.googlesource.com/c/1397665
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58613}
This reverts commit 3411e7c3e8.
Reason for revert: Breaks test expecations - https://ci.chromium.org/p/chromium/builders/luci.chromium.try/linux_chromium_rel_ng/260731
Original change's description:
> [parser] Create arrow function scopes while parsing the head
>
> This simplifies NextArrowFunctionInfo, allows us to Scope::Snapshot::Reparent
> directly rather than moving it, and allows us to skip reparenting in the simple
> parameter arrow function cases.
>
> This CL additionally fixes arrow function name inferring.
>
> Change-Id: Ie3e5ea778f3d7b84b2a10d4f4ff73931cfc9384a
> Reviewed-on: https://chromium-review.googlesource.com/c/1386147
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Commit-Queue: Toon Verwaest <verwaest@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#58405}
TBR=ishell@chromium.org,verwaest@chromium.org
# Not skipping CQ checks because original CL landed > 1 day ago.
Change-Id: I8f31b96f844f0673364bf435fa6c809e40d62fa3
Reviewed-on: https://chromium-review.googlesource.com/c/1388541
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58446}
This simplifies NextArrowFunctionInfo, allows us to Scope::Snapshot::Reparent
directly rather than moving it, and allows us to skip reparenting in the simple
parameter arrow function cases.
This CL additionally fixes arrow function name inferring.
Change-Id: Ie3e5ea778f3d7b84b2a10d4f4ff73931cfc9384a
Reviewed-on: https://chromium-review.googlesource.com/c/1386147
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58405}
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}
Instead of requiring the pattern that a SuspendGenerator must be
followed by a Return, make SuspendGenerator return directly. This can,
in the future, simplify some of the reasoning around generator suspends.
Change-Id: I94c0156a89dc0e1c0bc306bc57acf766f3b4deb5
Reviewed-on: https://chromium-review.googlesource.com/857463
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50748}
Nop bytecodes are required only for break locations in debugger. Since nop bytecode doesn't change program state we can remove all of them.
There are at least two changes which this CL produce:
- we don't provide break position when we load local variable (still provide when load variable from global),
- we don't provide break position for statements without actual break positions (e.g. "a;") - these expressions should be super rare and user always can set breakpoint before or after this statement.
More details in one pager: https://docs.google.com/a/google.com/document/d/1JXlQpfMa9vRojbE272b6GMBbrfh6m_00135iAUOJEz8/edit?usp=sharing
Bug: v8:6425
Change-Id: I4aee73d497a84f7b5d89caa6dda6d3060567dfda
Reviewed-on: https://chromium-review.googlesource.com/543161
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46742}
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: Adam Klein <adamk@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46687}
This includes several changes. From most to least interesting:
- No longer implement AwaitExpressions using a do-expression.
- Reduces frame-size of async generators by not allocating temporary
variables to hold results of Await epxressions.
- Streamline and reduce generated bytecodes for Await.
- Debugger no longer emits a debug::kCallBreakLocation breakpoint for
the JS-builtin call performed for Await, and instead only emits such
a breakpoint if the operand of Await is actually a call.
- Push fewer parameters to Await* builtins, using the receiver for the
first parameter (possible now that the CallRuntime invocation not
part of the AST).
- Adds a new Await AST node. No new members or anything, but it seemed
palatable to avoid having `if (is_await())` in a number of
VisitSuspend functions.
BUG=v8:5855, v8:5099, v8:4483
R=rmcilroy@chromium.org, kozyatinskiy@chromium.org, yangguo@chromium.orgTBR=bmeurer@chromium.org
Change-Id: I9cd3fda99cd40295c04fdf1aea01b5d83fac6caf
Reviewed-on: https://chromium-review.googlesource.com/558806
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46666}
In current implementation in expressions like await foo() we have break location right after foo call and before actual await.
And we additionally have a lot of other statement locations because of do scope.
Let's move async debugging closer to sync debugging and introduce only one break location for await - before awaited function call.
Bug: v8:6425,v8:6162
Change-Id: I7568767856022c49101e7f3b7e39a2e401d21644
Reviewed-on: https://chromium-review.googlesource.com/514046
Reviewed-by: Marja Hölttä <marja@chromium.org>
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45625}
