Summary:
This PR performs a major refactor of InferReferenceEffects to separate out the work on marking places with Effects from inferring FunctionEffects. The behavior should be identical after this change (see [internal sync](https://www.internalfb.com/intern/everpaste/?handle=GN74VxscnUaztTYDAL8q0CRWBIxibsIXAAAB)) but the FunctionEffect logic should be easier to work with.
These analyses are unfortunately still deeply linked--the FunctionEffect analysis needs to reason about the "current" value kind for each point in the program, while the InferReferenceEffects algorithm performs global updates on the state of the program (e.g. freezing). In the future, it might be possible to make these entirely separate passes if we store the ValueKind directly on places.
For the most part, the logic of reference effects and function effects can be cleanly separated: for each instruction and terminal, we visit its places and infer their effects, and then we visit its places and infer any function effects that they cause. The biggest wrinkle here is that when a transitive function freeze operation occurs, it has to happen *after* inferring the function effects on the place, because otherwise we may convert a value from Context to Frozen, which will cause the ContextualMutation function effect to be converted to a ReactMutation effect too early. This can be observed in a case like this:
```
export default component C() {
foo(() => {
const p = {};
return () => {
p['a'] = 1
};
});
}
```
Here when the outer function returns the inner function, it freezes the inner function which transitively freezes `p`. But before that freeze happens, we need to replay the ContextualMutation on the inner function to determine that the value is mutable in the outer context. If we froze `p` first, we would instead convert the ContextualMutation to a ReactMutation and error.
To handle this, InferReferenceEffects now delays the exection of the freezeValue action until after it's called the helper functions that generate function effects. So the order of operations on a given place is now
set effect --> generate function effects --> transitively freeze dependencies, if applicable
ghstack-source-id: 21cb50c140
Pull Request resolved: https://github.com/facebook/react/pull/30920
At Meta we have a pattern of using tagged template literals for features that are compiled away:
```
// Relay:
graphql`...graphql text...`
```
In many cases these tags produce a primitive value, and we can get even more optimal output if we can tell the compiler about these types. The new moduleTypeProvider gives us the ability to declare such types, this PR extends the compiler to use this type information for TaggedTemplateExpression values.
ghstack-source-id: 3cd6511b7f
Pull Request resolved: https://github.com/facebook/react/pull/30869
To prevent any difference in behavior, we check that the optionality of the inferred deps exactly matches the optionality of the manual dependencies. This required a fix, I was incorrectly inferring optionality of manual deps (they're only optional if OptionalTerminal.optional is true) - for nested cases of mixed optional/non-optional.
ghstack-source-id: afd49e89cc
Pull Request resolved: https://github.com/facebook/react/pull/30840
Branch terminals didn't have a fallthrough because they correspond to an outer terminal (optional, logical, etc) that has the "real" fallthrough. But understanding how branch terminals correspond to these outer terminals requires knowing the branch fallthrough. For example, `foo?.bar?.baz` creates terminals along the lines of:
```
bb0:
optional fallthrough=bb4
bb1:
optional fallthrough=bb3
bb2:
...
branch ... (fallthrough=bb3)
...
bb3:
...
branch ... (fallthrough=bb4)
...
bb4:
...
```
Without a fallthrough on `branch` terminals, it's unclear that the optional from bb0 has its branch node in bb3. With the fallthroughs, we can see look for a branch with the same fallthrough as the outer optional terminal to match them up.
ghstack-source-id: d48c623289
Pull Request resolved: https://github.com/facebook/react/pull/30814
Adds an `optional: boolean` property to each token in a DependencyPath, currently always set to false. Also updates the equality and printing logic for paths to account for this field.
Subsequent PRs will update our logic to determine which manual dependencies were optional, then we can start inferring optional deps as well.
ghstack-source-id: 66c2da2cfa
Pull Request resolved: https://github.com/facebook/react/pull/30813
Previously the path of a ReactiveScopeDependency was `Array<string>`. We need to track whether each property access is optional or not, so as a first step we change this to `Array<{property: string}>`, making space for an additional property in a subsequent PR.
ghstack-source-id: c5d38d72f6
Pull Request resolved: https://github.com/facebook/react/pull/30812
AnalyzeFunctions was reusing the `ReactiveScopeDependency` type since it happened to have a convenient shape, but we need to change this type to represent optionality. We now use a locally defined type instead.
ghstack-source-id: e305c6ede4
Pull Request resolved: https://github.com/facebook/react/pull/30811
Redo of an earlier (pre-OSS) PR to infer types of phi nodes. There are a few pieces to this:
1. Update InferTypes to infer the type of `phi.id.type`, not the unused `phi.type`.
2. Update the algorithm to verify that all the phi types are actually equal, not just have the same kind.
3. Handle circular types by removing the cycle.
However, that reveals another issue: InferMutableRanges currently infers the results of `Store` effects _after_ its fixpoint loop. That was fine when a Store could never occur on a phi (since they wouldn't have a type to get a function signature from). Now though, we can have Store effects occur on phis, and we need to ensure that this correctly updates the mutable range of the phi operands - recursively. See new test that fails without the fixpoint loop.
ghstack-source-id: 2e1b02844d
Pull Request resolved: https://github.com/facebook/react/pull/30796
Adds a new Environment config option which allows specifying a function that is called to resolve types of imported modules. The function is passed the name of the imported module (the RHS of the import stmt) and can return a TypeConfig, which is a recursive type of the following form:
* Object of valid identifier keys (or "*" for wildcard) and values that are TypeConfigs
* Function with various properties, whose return type is a TypeConfig
* or a reference to a builtin type using one of a small list (currently Ref, Array, MixedReadonly, Primitive)
Rather than have to eagerly supply all known types (most of which may not be used) when creating the config, this function can do so lazily. During InferTypes we call `getGlobalDeclaration()` to resolve global types. Originally this was just for known react modules, but if the new config option is passed we also call it to see if it can resolve a type. For `import {name} from 'module'` syntax, we first resolve the module type and then call `getPropertyType(moduleType, 'name')` to attempt to retrieve the property of the module (the module would obviously have to be typed as an object type for this to have a chance of yielding a result). If the module type is returned as null, or the property doesn't exist, we fall through to the original checking of whether the name was hook-like.
TODO:
* testing
* cache the results of modules so we don't have to re-parse/install their types on each LoadGlobal of the same module
* decide what to do if the module types are invalid. probably better to fatal rather than bail out, since this would indicate an invalid configuration.
ghstack-source-id: bfdbf67e3d
Pull Request resolved: https://github.com/facebook/react/pull/30771
The fixture from the previous PR was getting inconsistent behavior because of the following:
1. Create an object in a useMemo
2. Create a callback in a useCallback, where the callback captures the object from (1) into a local object, then passes that local object into a logging method. We have to assume the logging method could modify the local object, and transitively, the object from (1).
3. Call the callback during render.
4. Pass the callback to JSX.
We correctly infer that the object from (1) is captured and modified in (2). However, in (4) we transitively freeze the callback. When transitively freezing functions we were previously doing two things: updating our internal abstract model of the program values to reflect the values as being frozen *and* also updating function operands to change their effects to freeze.
As the case above demonstrates, that can clobber over information about real potential mutability. The potential fix here is to only walk our abstract value model to mark values as frozen, but _not_ override operand effects. Conceptually, this is a forward data flow propagation — but walking backward to update effects is pushing information backwards in the algorithm. An alternative would be to mark that data was propagated backwards, and trigger another loop over the CFG to propagate information forward again given the updated effects. But the fix in this PR is more correct.
ghstack-source-id: c05e716f37
Pull Request resolved: https://github.com/facebook/react/pull/30766
Summary:
Refs, as stable values that the rules of react around mutability do not apply to, currently are treated as having mutable ranges, and through aliasing, this can extend the mutable range for other values and disrupt good memoization for those values. This PR excludes refs and their .current values from having mutable ranges.
Note that this is unsafe if ref access is allowed in render: if a mutable value is assigned to ref.current and then ref.current is mutated later, we won't realize that the original mutable value's range extends.
ghstack-source-id: e8f36ac25e
Pull Request resolved: https://github.com/facebook/react/pull/30713
This PR updates to use SSA form through the entire compilation pipeline. This means that in both HIR form and ReactiveFunction form, `Identifier` instances map 1:1 to `IdentifierId` values. If two identifiers have the same IdentifierId, they are the same instance. What this means is that all our passes can use this more precise information to determine if two particular identifiers are not just the same variable, but the same SSA "version" of that variable.
However, some parts of our analysis really care about program variables as opposed to SSA versions, and were relying on LeaveSSA to reset identifiers such that all Identifier instances for a particular program variable would have the same IdentifierId (though not necessarily the same Identifier instance). With LeaveSSA removed, those analysis passes can now use DeclarationId instead to uniquely identify a program variable.
Note that this PR surfaces some opportunties to improve edge-cases around reassigned values being declared/reassigned/depended-upon across multiple scopes. Several passes could/should use IdentifierId to more precisely identify exactly which values are accessed - for example, a scope that reassigns `x` but doesn't use `x` prior to reassignment doesn't have to take a dependency on `x`. But today we take a dependnecy.
My approach for these cases was to add a "TODO LeaveSSA" comment with notes and the name of the fixture demonstrating the difference, but to intentionally preserve the existing behavior (generally, switching to use DeclarationId when IdentifierId would have been more precise).
Beyond updating passes to use DeclarationId instead of Identifier/IdentifierId, the other change here is to extract out the remaining necessary bits of LeaveSSA into a new pass that rewrites InstructionKind (const/let/reassign/etc) based on whether a value is actually const or has reassignments and should be let.
ghstack-source-id: 69afdaee5f
Pull Request resolved: https://github.com/facebook/react/pull/30573
Adds `Identifier.declarationId` and the new `DeclarationId` (simulated) opaque type. DeclarationId allows uniquely identifying a variable in the original source, ie regardless of reassignments. This allows us to stay in SSA form throughout compilation (see next diff) while still being able to distinguish SSA versions (via IdentifierId) and non-SSA versions (DeclarationId).
ghstack-source-id: f2547a58aa
Pull Request resolved: https://github.com/facebook/react/pull/30569
ghstack failed to land #30552 properly, resubmitting
Developers sometimes use `useMemo()` as a way to conditionally execute code, including conditionally calling setState. However, the compiler may remove existing useMemo calls if they are not necessary, which _should_ always be a safe optimization. If the useMemo has side effects (eg sets state), then this isn't safe.
This PR improves ValidateNoSetStateInRender to disallow any setState in useMemo (even if it's conditional), expanding on the previous check for unconditional setState in render. Note that the approach uses the StartMemoize/FinishMemoize instructions added in DropManualMemo to know whether a particular setState call is within a useMemo or not. This means enabling the validation in DropManualMemo when the setState validation is enabled, but that's fine since that validation is on everywhere by default (_except_ for in fixtures, which we have a todo for)
ghstack-source-id: 65bb3289c3
Pull Request resolved: https://github.com/facebook/react/pull/30583
Updates the prettier config to format all `.ts` and `.tsx` files in the
repo using the existing defaults and removing overrides.
The first commit in this PR contains the config changes, the second is
just the result of running `yarn prettier-all`.
Updated version of #29758 removing `useFormState` since that was the
previous name for `useActionState`.
---------
Co-authored-by: Hieu Do <hieudn.uh@gmail.com>
Fixes a bug found by mofeiZ in #29878. When we merge queued states, if the new state does not introduce changes relative to the queued state we should use the queued state, not the new state.
ghstack-source-id: c59f69de15
Pull Request resolved: https://github.com/facebook/react/pull/29879
## Summary
See #29737
## How did you test this change?
As the feature requires module support and the test runner does
currently not support running tests as modules, I could only test it via
playground.
Fixes false positives where we currently disallow mutations of refs from callbacks passed to JSX, if the ref is also passed to jsx. We consider these to be mutations of "frozen" values, but refs are explicitly allowed to have interior mutability. The fix is to always allow (at leat within InferReferenceEffects) for refs to be mutated. This means we completely rely on ValidateNoRefAccessInRender to validate ref access and stop reporting false positives.
ghstack-source-id: 1a30609f5f
Pull Request resolved: https://github.com/facebook/react/pull/29733
Summary
The dispatch function from useReducer is stable, so it is also non-reactive.
the related PR: #29665
the related comment: #29674 (comment)
I am not sure if the location of the new test file is appropriate😅.
How did you test this change?
Added the specific test compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/useReducer-returned-dispatcher-is-non-reactive.expect.md.
Summary: Using the change detection code to debug codebases that violate the rules of react is a lot easier when we have a source location corresponding to the value that has changed inappropriately. I didn't see an easy way to track that information in the existing data structures at the point of codegen, so this PR adds locations to identifiers and reactive scopes (the location of a reactive scope is the range of the locations of its included identifiers).
I'm interested if there's a better way to do this that I missed!
ghstack-source-id: aed5f7edda
Pull Request resolved: https://github.com/facebook/react/pull/29658
Fixes https://x.com/raibima/status/1794395807216738792
The issue is that if you pass a global-modifying function as prop to JSX, we currently report that it's invalid to modify a global during rendering. The problem is that we don't really know when/if the child component will actually call that function prop. It would be against the rules to call the function during render, but it's totally fine to call it during an event handler or from a useEffect.
Since we don't know at the call-site how the child will use the function, we should allow such calls. In the future we could improve this in a few ways:
* For all functions that modify globals, codegen an assertion or warning into the function that fires if it's called "during render". We'd have to precisely define what "during render" is, but this would at least help developers catch this dynamically.
* Use the type system to distinguish "event/effect" and "render" functions to help developers avoid accidentally mutating globals during render.
ghstack-source-id: 4aba4e6d21
Pull Request resolved: https://github.com/facebook/react/pull/29591
No-op refactor to make Environment#getGlobalDeclaration() take a NonLocalBinding instead of just a name. The idea is that in subsequent PRs we can use information about the binding to resolve a type more accurately. For example, we can resolve `Array` differently if its an import or local and not the global Array. Similar for resolving local `useState` differently than the one from React.
ghstack-source-id: c8063e6fb8
Pull Request resolved: https://github.com/facebook/react/pull/29189
We currently use `LoadGlobal` and `StoreGlobal` to represent any read (or write) of a variable defined outside the component or hook that is being compiled. This is mostly fine, but for a lot of things we want to do going forward (resolving types across modules, for example) it helps to understand the actual source of a variable.
This PR is an incremental step in that direction. We continue to use LoadGlobal/StoreGlobal, but LoadGlobal now has a `binding:NonLocalBinding` instead of just the name of the global. The NonLocalBinding type tells us whether it was an import (and which kind, the source module name etc), a module-local binding, or a true global. By keeping the LoadGlobal/StoreGlobal instructions, most code that deals with "anything not declared locally" doesn't have to care about the difference. However, code that _does_ want to know the source of the value can figure it out.
ghstack-source-id: e701d4ebc0
Pull Request resolved: https://github.com/facebook/react/pull/29188
By default, React Compiler will skip compilation if it cannot preserve existing memoization. Ie, if the code has an existing `useMemo()` or `useCallback()` and the compiler cannot determine that it is safe to keep that memoization — or do even better — then we'll leave the code alone. The actual compilation doesn't use any hints from existing memo calls, this is purely to check and avoid regressing any specific memoization that developers may have already applied.
However, we were accidentally reporting some false-positive _validation_ errors due to the StartMemoize and FinishMemoize instructions that we emit to track where the memoization was in the source code. This is now fixed.
Fixes#29131Fixes#29132
ghstack-source-id: 9f6b8dbc50
Pull Request resolved: https://github.com/facebook/react/pull/29154
Mike Vitousek
Joe Savona
Jan Kassens
Joseph Savona
Niklas Mollenhauer
XiaoPi