To help bootstrap the new inference model, this PR adds a helper that takes a legacy FunctionSignature and converts into a list of (new) AliasingEffects. This conversion tries to make explicit all the implicit handling of InferReferenceEffects and previous FunctionSignature.
For example, the signature for Array.proto.pop has a calleeEffect of `Store`. Nowhere does it say that the receiver flows into the result! There's an implicit behavior that the receiver flows into the result. The new function makes this explicit by emitting a `Capture receiver -> lvalue` effect.
So far I confirmed that this works for Array.proto.push() if i hard code the inference to ignore new-style aliasing signatures. I'll continue to refine it going forward as I start running the new inference on more fixtures.
[ghstack-poisoned]
To help bootstrap the new inference model, this PR adds a helper that takes a legacy FunctionSignature and converts into a list of (new) AliasingEffects. This conversion tries to make explicit all the implicit handling of InferReferenceEffects and previous FunctionSignature.
For example, the signature for Array.proto.pop has a calleeEffect of `Store`. Nowhere does it say that the receiver flows into the result! There's an implicit behavior that the receiver flows into the result. The new function makes this explicit by emitting a `Capture receiver -> lvalue` effect.
So far I confirmed that this works for Array.proto.push() if i hard code the inference to ignore new-style aliasing signatures. I'll continue to refine it going forward as I start running the new inference on more fixtures.
[ghstack-poisoned]
To help bootstrap the new inference model, this PR adds a helper that takes a legacy FunctionSignature and converts into a list of (new) AliasingEffects. This conversion tries to make explicit all the implicit handling of InferReferenceEffects and previous FunctionSignature.
For example, the signature for Array.proto.pop has a calleeEffect of `Store`. Nowhere does it say that the receiver flows into the result! There's an implicit behavior that the receiver flows into the result. The new function makes this explicit by emitting a `Capture receiver -> lvalue` effect.
So far I confirmed that this works for Array.proto.push() if i hard code the inference to ignore new-style aliasing signatures. I'll continue to refine it going forward as I start running the new inference on more fixtures.
[ghstack-poisoned]
Adds an aliasing signature for Array.prototype.push and fixes up the logic for consuming these signatures during effect inference. As the test fixture shows, we correctly model the capturing. Mutable values that are captured into the array count as co-mutated if the array itself is transitively mutated later, while mutable values captured after such transitive mutation are not considered co-mutated.
The implementation is based on the fact that the final `push` call is only locally mutating the array. During the phase that looks at local mutations we are only tracking direct aliases, and the push doesn't directly alias the items to the array, it only captures them.
[ghstack-poisoned]
Adds an aliasing signature for Array.prototype.push and fixes up the logic for consuming these signatures during effect inference. As the test fixture shows, we correctly model the capturing. Mutable values that are captured into the array count as co-mutated if the array itself is transitively mutated later, while mutable values captured after such transitive mutation are not considered co-mutated.
The implementation is based on the fact that the final `push` call is only locally mutating the array. During the phase that looks at local mutations we are only tracking direct aliases, and the push doesn't directly alias the items to the array, it only captures them.
[ghstack-poisoned]
Adds an aliasing signature for Array.prototype.push and fixes up the logic for consuming these signatures during effect inference. As the test fixture shows, we correctly model the capturing. Mutable values that are captured into the array count as co-mutated if the array itself is transitively mutated later, while mutable values captured after such transitive mutation are not considered co-mutated.
The implementation is based on the fact that the final `push` call is only locally mutating the array. During the phase that looks at local mutations we are only tracking direct aliases, and the push doesn't directly alias the items to the array, it only captures them.
[ghstack-poisoned]
See comments in code. The idea is that rather than immediately processing function expression effects when declaring the function, we record Capture effects for context variables that may be captured/mutated in the function. Then, transitive mutations of the function value itself will extend the range of these values via the normal captured value comutation inference established earlier in the stack (if capture a -> b, then transitiveMutate(b) => mutate(a)). So capture contextVar -> function and transitiveMutate(function) => mutate(contextVar).
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See comments in code. The idea is that rather than immediately processing function expression effects when declaring the function, we record Capture effects for context variables that may be captured/mutated in the function. Then, transitive mutations of the function value itself will extend the range of these values via the normal captured value comutation inference established earlier in the stack (if capture a -> b, then transitiveMutate(b) => mutate(a)). So capture contextVar -> function and transitiveMutate(function) => mutate(contextVar).
[ghstack-poisoned]
See comments in code. The idea is that rather than immediately processing function expression effects when declaring the function, we record Capture effects for context variables that may be captured/mutated in the function. Then, transitive mutations of the function value itself will extend the range of these values via the normal captured value comutation inference established earlier in the stack (if capture a -> b, then transitiveMutate(b) => mutate(a)). So capture contextVar -> function and transitiveMutate(function) => mutate(contextVar).
[ghstack-poisoned]
ImmutableCapture allows us to record information flow for escape analysis purposes, without impacting mutable range analysis. All of Alias, Capture, and CreateFrom now downgrade to ImmutableCapture if the `from` value is frozen. Globals and primitives are conceptually copy types and don't record any information flow at all. I guess we could add a `Copy` effect if we wanted but i haven't seen a need for it yet.
Related, previously CreateFrom was always paired with Capture when constructing effects. But I had also coded up the inference to sort of treat them the same. So this diff makes that official, and means CreateFrom is a valid third way to represent data flow and not just creation. When applied, CreateFrom will turn into: ImmutableCapture for frozen values, Capture for mutable values, and disappear for globals/primitives.
A final tweak is to change range inference to ensure that range.start is non-zero if the value is mutated.
[ghstack-poisoned]
ImmutableCapture allows us to record information flow for escape analysis purposes, without impacting mutable range analysis. All of Alias, Capture, and CreateFrom now downgrade to ImmutableCapture if the `from` value is frozen. Globals and primitives are conceptually copy types and don't record any information flow at all. I guess we could add a `Copy` effect if we wanted but i haven't seen a need for it yet.
Related, previously CreateFrom was always paired with Capture when constructing effects. But I had also coded up the inference to sort of treat them the same. So this diff makes that official, and means CreateFrom is a valid third way to represent data flow and not just creation. When applied, CreateFrom will turn into: ImmutableCapture for frozen values, Capture for mutable values, and disappear for globals/primitives.
A final tweak is to change range inference to ensure that range.start is non-zero if the value is mutated.
[ghstack-poisoned]
ImmutableCapture allows us to record information flow for escape analysis purposes, without impacting mutable range analysis. All of Alias, Capture, and CreateFrom now downgrade to ImmutableCapture if the `from` value is frozen. Globals and primitives are conceptually copy types and don't record any information flow at all. I guess we could add a `Copy` effect if we wanted but i haven't seen a need for it yet.
Related, previously CreateFrom was always paired with Capture when constructing effects. But I had also coded up the inference to sort of treat them the same. So this diff makes that official, and means CreateFrom is a valid third way to represent data flow and not just creation. When applied, CreateFrom will turn into: ImmutableCapture for frozen values, Capture for mutable values, and disappear for globals/primitives.
A final tweak is to change range inference to ensure that range.start is non-zero if the value is mutated.
[ghstack-poisoned]
Distinguish the various forms of mutation, and do basic replaying of these effects when the function is created (imperfect, temporary).
[ghstack-poisoned]
Distinguish the various forms of mutation, and do basic replaying of these effects when the function is created (imperfect, temporary).
[ghstack-poisoned]
Distinguish the various forms of mutation, and do basic replaying of these effects when the function is created (imperfect, temporary).
[ghstack-poisoned]
This PR gets a first fixture working end-to-end with the new mutability and aliasing model. Key changes:
* Add a feature flag to enable the model. When enabled we no longer call InferReferenceEffects or InferMutableRanges, and instead use the new equivalents.
* Adds a pass that infers Place-specific effects based on mutable ranges and instruction effects. This is necessary to satisfy existing code that requires operand effects to be populated.
* Adds a pass that infers the outwardly-visible capturing/aliasing behavior of a function expression. The idea is that this can bubble up and be used in conjunction with the `Apply` effect to get precise inference of things like `array.map(() => { ... })`.
[ghstack-poisoned]
This PR gets a first fixture working end-to-end with the new mutability and aliasing model. Key changes:
* Add a feature flag to enable the model. When enabled we no longer call InferReferenceEffects or InferMutableRanges, and instead use the new equivalents.
* Adds a pass that infers Place-specific effects based on mutable ranges and instruction effects. This is necessary to satisfy existing code that requires operand effects to be populated.
* Adds a pass that infers the outwardly-visible capturing/aliasing behavior of a function expression. The idea is that this can bubble up and be used in conjunction with the `Apply` effect to get precise inference of things like `array.map(() => { ... })`.
[ghstack-poisoned]
This PR gets a first fixture working end-to-end with the new mutability and aliasing model. Key changes:
* Add a feature flag to enable the model. When enabled we no longer call InferReferenceEffects or InferMutableRanges, and instead use the new equivalents.
* Adds a pass that infers Place-specific effects based on mutable ranges and instruction effects. This is necessary to satisfy existing code that requires operand effects to be populated.
* Adds a pass that infers the outwardly-visible capturing/aliasing behavior of a function expression. The idea is that this can bubble up and be used in conjunction with the `Apply` effect to get precise inference of things like `array.map(() => { ... })`.
[ghstack-poisoned]
Alternate take at a new mutability and alising model, aiming to replace `InferReferenceEffects` and `InferMutableRanges`. My initial passes at this were more complicated than necessary, and I've iterated to refine and distill this down to the core concepts. There are two effects that track information flow: `capture` and `alias`:
* Given distinct values A and B. After capture A -> B, mutate(B) does *not* modify A. This more precisely captures the semantic of the previous `Store` effect. As an example, `array.push(item)` has the effect `capture item -> array` and `mutate(array)`. The array is modified, not the item.
* Given distinct values A and B. After alias A -> B, mutate(B) *does* modify A. This is because B now refers to the same value as A.
* Given distinct values A and B, after *either* capture A -> B *or* alias A -> B, transitiveMutate(B) counts as a mutation of A. Transitive mutation is the default, and places that previously used `Store` will use non-transitive mutate effects instead.
Conceptually "capture A -> B" means that a reference to A was "captured" (or stored) within A, but there is not a directly aliasing. Whereas "alias A -> B" means literal value aliasing.
The idea is that our previous sequential fixpoint loops in InferMutableRanges can instead work by first looking at transitive mutations, then look at non-transitive mutations. And aliasing groups can be built purely based on the `alias` effect.
Lots more to do here but the structure is coming together.
[ghstack-poisoned]
Alternate take at a new mutability and alising model, aiming to replace `InferReferenceEffects` and `InferMutableRanges`. My initial passes at this were more complicated than necessary, and I've iterated to refine and distill this down to the core concepts. There are two effects that track information flow: `capture` and `alias`:
* Given distinct values A and B. After capture A -> B, mutate(B) does *not* modify A. This more precisely captures the semantic of the previous `Store` effect. As an example, `array.push(item)` has the effect `capture item -> array` and `mutate(array)`. The array is modified, not the item.
* Given distinct values A and B. After alias A -> B, mutate(B) *does* modify A. This is because B now refers to the same value as A.
* Given distinct values A and B, after *either* capture A -> B *or* alias A -> B, transitiveMutate(B) counts as a mutation of A. Transitive mutation is the default, and places that previously used `Store` will use non-transitive mutate effects instead.
Conceptually "capture A -> B" means that a reference to A was "captured" (or stored) within A, but there is not a directly aliasing. Whereas "alias A -> B" means literal value aliasing.
The idea is that our previous sequential fixpoint loops in InferMutableRanges can instead work by first looking at transitive mutations, then look at non-transitive mutations. And aliasing groups can be built purely based on the `alias` effect.
Lots more to do here but the structure is coming together.
[ghstack-poisoned]
Alternate take at a new mutability and alising model, aiming to replace `InferReferenceEffects` and `InferMutableRanges`. My initial passes at this were more complicated than necessary, and I've iterated to refine and distill this down to the core concepts. There are two effects that track information flow: `capture` and `alias`:
* Given distinct values A and B. After capture A -> B, mutate(B) does *not* modify A. This more precisely captures the semantic of the previous `Store` effect. As an example, `array.push(item)` has the effect `capture item -> array` and `mutate(array)`. The array is modified, not the item.
* Given distinct values A and B. After alias A -> B, mutate(B) *does* modify A. This is because B now refers to the same value as A.
* Given distinct values A and B, after *either* capture A -> B *or* alias A -> B, transitiveMutate(B) counts as a mutation of A. Transitive mutation is the default, and places that previously used `Store` will use non-transitive mutate effects instead.
Conceptually "capture A -> B" means that a reference to A was "captured" (or stored) within A, but there is not a directly aliasing. Whereas "alias A -> B" means literal value aliasing.
The idea is that our previous sequential fixpoint loops in InferMutableRanges can instead work by first looking at transitive mutations, then look at non-transitive mutations. And aliasing groups can be built purely based on the `alias` effect.
Lots more to do here but the structure is coming together.
[ghstack-poisoned]
Alternate take at a new mutability and alising model, aiming to replace `InferReferenceEffects` and `InferMutableRanges`. My initial passes at this were more complicated than necessary, and I've iterated to refine and distill this down to the core concepts. There are two effects that track information flow: `capture` and `alias`:
* Given distinct values A and B. After capture A -> B, mutate(B) does *not* modify A. This more precisely captures the semantic of the previous `Store` effect. As an example, `array.push(item)` has the effect `capture item -> array` and `mutate(array)`. The array is modified, not the item.
* Given distinct values A and B. After alias A -> B, mutate(B) *does* modify A. This is because B now refers to the same value as A.
* Given distinct values A and B, after *either* capture A -> B *or* alias A -> B, transitiveMutate(B) counts as a mutation of A. Transitive mutation is the default, and places that previously used `Store` will use non-transitive mutate effects instead.
Conceptually "capture A -> B" means that a reference to A was "captured" (or stored) within A, but there is not a directly aliasing. Whereas "alias A -> B" means literal value aliasing.
The idea is that our previous sequential fixpoint loops in InferMutableRanges can instead work by first looking at transitive mutations, then look at non-transitive mutations. And aliasing groups can be built purely based on the `alias` effect.
Lots more to do here but the structure is coming together.
[ghstack-poisoned]
Alternate take at a new mutability and alising model, aiming to replace `InferReferenceEffects` and `InferMutableRanges`. My initial passes at this were more complicated than necessary, and I've iterated to refine and distill this down to the core concepts. There are two effects that track information flow: `capture` and `alias`:
* Given distinct values A and B. After capture A -> B, mutate(B) does *not* modify A. This more precisely captures the semantic of the previous `Store` effect. As an example, `array.push(item)` has the effect `capture item -> array` and `mutate(array)`. The array is modified, not the item.
* Given distinct values A and B. After alias A -> B, mutate(B) *does* modify A. This is because B now refers to the same value as A.
* Given distinct values A and B, after *either* capture A -> B *or* alias A -> B, transitiveMutate(B) counts as a mutation of A.
Conceptually "capture A -> B" means that a reference to A was "captured" (or stored) within A, but there is not a directly aliasing. Whereas "alias A -> B" means literal value aliasing.
The idea is that our previous sequential fixpoint loops in InferMutableRanges can instead work by first looking at transitive mutations, then look at non-transitive mutations. And aliasing groups can be built purely based on the `alias` effect.
Lots more to do here but the structure is coming together.
[ghstack-poisoned]
Syncing this stack internally there is a small percentage of files that lose memoization, generally for callbacks. The repro here tries to get at the core pattern, where a parameter escapes into a mutable return value. This makes the callback appear mutable, and means that calls like array.map aren't able to optimize as well — even if the array itself is transitively immutable.
The challenge is that we can't really distinguish between just capturing and true mutation right now — AnalyzeFunctions kind of has to pick one, and consider both a mutation.
[ghstack-poisoned]
Syncing this stack internally there is a small percentage of files that lose memoization, generally for callbacks. The repro here tries to get at the core pattern, where a parameter escapes into a mutable return value. This makes the callback appear mutable, and means that calls like array.map aren't able to optimize as well — even if the array itself is transitively immutable.
The challenge is that we can't really distinguish between just capturing and true mutation right now — AnalyzeFunctions kind of has to pick one, and consider both a mutation.
[ghstack-poisoned]
Basically we track a `SuspenseListRow` on the task. These keep track of
"pending tasks" that block the row. A row is blocked by:
- First itself completing rendering.
- A previous row completing.
- Any tasks inside the row and before the Suspense boundary inside the
row. This is mainly because we don't yet know if we'll discover more
SuspenseBoundaries.
- Previous row's SuspenseBoundaries completing.
If a boundary might get outlined, then we can't consider it completed
until we have written it because it determined whether other future
boundaries in the row can finish.
This is just handling basic semantics. Features not supported yet that
need follow ups later:
- CSS dependencies of previous rows should be added as dependencies of
future row's suspense boundary. Because otherwise if the client is
blocked on CSS then a previous row could be blocked but the server
doesn't know it.
- I need a second pass on nested SuspenseList semantics.
- `revealOrder="together"`
- `tail="hidden"`/`tail="collapsed"`. This needs some new runtime
semantics to the Fizz runtime and to allow the hydration to handle
missing rows in the HTML. This should also be future compatible with
AsyncIterable where we don't know how many rows upfront.
- Need to double check resuming semantics.
---------
Co-authored-by: Sebastian "Sebbie" Silbermann <silbermann.sebastian@gmail.com>
When needed.
For the external runtime we always include this wrapper.
For others, we only include it if we have an ViewTransitions affecting.
If we discover the ViewTransitions late, then we can upgrade an already
emitted instruction.
This doesn't yet do anything useful with it, that's coming in a follow
up. This is just the mechanism for how it gets installed.
We decremented `allPendingTasks` after invoking `onShellReady`. Which
means that in that scope it wasn't considered fully complete.
Since the pattern for flushing in Node.js is to start piping in
`onShellReady` and that's how you can get sync behavior, this led us to
think that we had more work left to do. For example we emitted the
`writeShellTimeInstruction` in this scenario before.
Stacked on #33194 and #33200.
When Suspense boundaries reveal during streaming, the Fizz runtime will
be responsible for animating the reveal if necessary (not in this PR).
However, for the future runtime to know what to do it needs to know
about the `<ViewTransition>` configuration to apply.
Ofc, these are virtual nodes that disappear from the HTML. We could
model them as comments like we do with other virtual nodes like Suspense
and Activity. However, that doesn't let us target them with
querySelector and CSS (for no-JS transitions). We also don't have to
model every ViewTransition since not every combination can happen using
only the server runtime. So instead this collapses `<ViewTransition>`
and applies the configuration to the inner DOM nodes.
```js
<ViewTransition name="hi">
<div />
<div />
</ViewTransition>
```
Becomes:
```html
<div vt-name="hi" vt-update="auto"></div>
<div vt-name="hi_1" vt-update="auto"></div>
```
I use `vt-` prefix as opposed to `data-` to keep these virtual
attributes away from user specific ones but we're effectively claiming
this namespace.
There are four triggers `vt-update`, `vt-enter`, `vt-exit` and
`vt-share`. The server resolves which ones might apply to this DOM node.
The value represents the class name (after resolving
view-transition-type mappings) or `"auto"` if no specific class name is
needed but this is still a trigger.
The value can also be `"none"`. This is different from missing because
for example an `vt-update="none"` will block mutations inside it from
triggering the boundary where as a missing `vt-update` would bubble up
to be handled by a parent.
`vt-name` is technically only necessary when `vt-share` is specified to
find a pair. However, since an explicit name can also be used to target
specific CSS selectors, we include it even for other cases.
We want to exclude as many of these annotations as possible.
`vt-enter` can only affect the first DOM node inside a Suspense
boundary's content since the reveal would cause it to enter but nothing
deeper inside. Similarly `vt-exit` can only affect the first DOM node
inside a fallback. So for every other case we can exclude them. (For
future MPA ViewTransitions of the whole document it might also be
something we annotate to children inside the `<body>` as well.) Ideally
we'd only include `vt-enter` for Suspense boundaries that actually
flushed a fallback but since we prepare all that content earlier it's
hard to know.
`vt-share` can be anywhere inside an fallback or content. Technically we
don't have to include it outside the root most Suspense boundary or for
boundaries that are inlined into the root shell. However, this is tricky
to detect. It would also not be correct for future MPA ViewTransitions
because in that case the shared scenario can affect anything in the two
documents so it needs to be in every node everywhere which is
effectively what we do. If a `share` class is specified but it has no
explicit name, we can exclude it since it can't match anything.
`vt-update` is only necessary if something below or a sibling might
update like a Suspense boundary. However, since we don't know when
rendering a segment if it'll later asynchronously add a Suspense
boundary later we have to assume that anywhere might have a child. So
these are always included. We collapse to use the inner most one when
directly nested though since that's the one that ends up winning.
There are some weird edge cases that can't be fully modeled by the lack
of virtual nodes.
Removes the `isFallback` flag on Tasks and tracks it on the
formatContext instead.
Less memory and avoids passing and tracking extra arguments to all the
pushStartInstance branches that doesn't need it.
We'll need to be able to track more Suspense related contexts on this
for View Transitions anyway.
This is a partial revert of #33094. It's true that we don't need the
server and client ViewTransition names to line up. However the server
does need to be able to generate deterministic names for itself. The
cheapest way to do that is using the useId algorithm. When it's used by
the server, the client needs to also materialize an ID even if it
doesn't use it.
And that doesn't disable with `update="none"`.
The principle here is that we want the content of a Portal to animate if
other things are animating with it but if other things aren't animating
then we don't.
Stacked on #33160, #33162, #33186 and #33188.
We have a special case that's awkward for default indicators. When you
start a new async Transition from `React.startTransition` then there's
not yet any associated root with the Transition because you haven't
necessarily `setState` on anything yet until the promise resolves.
That's what `entangleAsyncAction` handles by creating a lane that
everything entangles with until all async actions are done.
If there are no sync updates before the end of the event, we should
trigger a default indicator until either the async action completes
without update or if it gets entangled with some roots we should keep it
going until those roots are done.
Stacked on #33160.
By default, if `onDefaultTransitionIndicator` is not overridden, this
will trigger a fake Navigation event using the Navigation API. This is
intercepted to create an on-going navigation until we complete the
Transition. Basically each default Transition is simulated as a
Navigation.
This triggers the native browser loading state (in Chrome at least). So
now by default the browser spinner spins during a Transition if no other
loading state is provided. Firefox and Safari hasn't shipped Navigation
API yet and even in the flag Safari has, it doesn't actually trigger the
native loading state.
To ensures that you can still use other Navigations concurrently, we
don't start our fake Navigation if there's one on-going already.
Similarly if our fake Navigation gets interrupted by another. We wait
for on-going ones to finish and then start a new fake one if we're
supposed to be still pending.
There might be other routers on the page that might listen to intercept
Navigation Events. Typically you'd expect them not to trigger a refetch
when navigating to the same state. However, if they want to detect this
we provide the `"react-transition"` string in the `info` field for this
purpose.