[compiler] Kill markReactiveIdentifier and friends

Summary:
With the previous PR we no longer need to mark identifiers as reactive in contexts where we don't have places. We already deleted most uses of markReactiveId; the last case was to track identifiers through loadlocals etc -- but we already use a disjoint alias map that accounts for loadlocals when setting reactivity.

ghstack-source-id: 69ce0a78b0729da3fe9d08177bf7d827af5325fb
Pull Request resolved: #31178

compiler/packages/babel-plugin-react-compiler/src/Inference/InferReactivePlaces.ts

@@ -157,7 +157,6 @@ export function inferReactivePlaces(fn: HIRFunction): void {
  }
 
  do {
- const identifierMapping = new Map<Identifier, Identifier>();
  for (const [, block] of fn.body.blocks) {
  let hasReactiveControl = isReactiveControlledBlock(block.id);
 
@@ -233,10 +232,6 @@ export function inferReactivePlaces(fn: HIRFunction): void {
  case Effect.ConditionallyMutate:
  case Effect.Mutate: {
  if (isMutable(instruction, operand)) {
- const resolvedId = identifierMapping.get(operand.identifier);
- if (resolvedId !== undefined) {
- reactiveIdentifiers.markReactiveIdentifier(resolvedId);
- }
  reactiveIdentifiers.markReactive(operand);
  }
  break;
@@ -263,31 +258,6 @@ export function inferReactivePlaces(fn: HIRFunction): void {
  }
  }
  }
-
- switch (value.kind) {
- case 'LoadLocal': {
- identifierMapping.set(
- instruction.lvalue.identifier,
- value.place.identifier,
- );
- break;
- }
- case 'PropertyLoad':
- case 'ComputedLoad': {
- const resolvedId =
- identifierMapping.get(value.object.identifier) ??
- value.object.identifier;
- identifierMapping.set(instruction.lvalue.identifier, resolvedId);
- break;
- }
- case 'LoadContext': {
- identifierMapping.set(
- instruction.lvalue.identifier,
- value.place.identifier,
- );
- break;
- }
- }
  }
  for (const operand of eachTerminalOperand(block.terminal)) {
  reactiveIdentifiers.isReactive(operand);
@@ -372,27 +342,19 @@ class ReactivityMap {
  }
 
  isReactive(place: Place): boolean {
- const reactive = this.isReactiveIdentifier(place.identifier);
+ const identifier =
+ this.aliasedIdentifiers.find(place.identifier) ?? place.identifier;
+ const reactive = this.reactive.has(identifier.id);
  if (reactive) {
  place.reactive = true;
  }
  return reactive;
  }
 
- isReactiveIdentifier(inputIdentifier: Identifier): boolean {
- const identifier =
- this.aliasedIdentifiers.find(inputIdentifier) ?? inputIdentifier;
- return this.reactive.has(identifier.id);
- }
-
  markReactive(place: Place): void {
  place.reactive = true;
- this.markReactiveIdentifier(place.identifier);
- }
-
- markReactiveIdentifier(inputIdentifier: Identifier): void {
  const identifier =
- this.aliasedIdentifiers.find(inputIdentifier) ?? inputIdentifier;
+ this.aliasedIdentifiers.find(place.identifier) ?? place.identifier;
  if (!this.reactive.has(identifier.id)) {
  this.hasChanges = true;
  this.reactive.add(identifier.id);