AnalyseFunctions.ts — react Source File

Source Code

/**
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */

import {CompilerError} from '../CompilerError';
import {Effect, HIRFunction, IdentifierId, makeInstructionId} from '../HIR';
import {deadCodeElimination} from '../Optimization';
import {inferReactiveScopeVariables} from '../ReactiveScopes';
import {rewriteInstructionKindsBasedOnReassignment} from '../SSA';
import {assertExhaustive} from '../Utils/utils';
import {inferMutationAliasingEffects} from './InferMutationAliasingEffects';
import {inferMutationAliasingRanges} from './InferMutationAliasingRanges';

export default function analyseFunctions(func: HIRFunction): void {
  for (const [_, block] of func.body.blocks) {
    for (const instr of block.instructions) {
      switch (instr.value.kind) {
        case 'ObjectMethod':
        case 'FunctionExpression': {
          lowerWithMutationAliasing(instr.value.loweredFunc.func);

          /**
           * Reset mutable range for outer inferReferenceEffects
           */
          for (const operand of instr.value.loweredFunc.func.context) {
            /**
             * NOTE: inferReactiveScopeVariables makes identifiers in the scope
             * point to the *same* mutableRange instance. Resetting start/end
             * here is insufficient, because a later mutation of the range
             * for any one identifier could affect the range for other identifiers.
             */
            operand.identifier.mutableRange = {
              start: makeInstructionId(0),
              end: makeInstructionId(0),
            };
            operand.identifier.scope = null;
          }
          break;
        }
      }
    }
  }
}

function lowerWithMutationAliasing(fn: HIRFunction): void {
  /**
   * Phase 1: similar to lower(), but using the new mutation/aliasing inference
   */
  analyseFunctions(fn);
  inferMutationAliasingEffects(fn, {isFunctionExpression: true});
  deadCodeElimination(fn);
  const functionEffects = inferMutationAliasingRanges(fn, {
    isFunctionExpression: true,
  }).unwrap();
  rewriteInstructionKindsBasedOnReassignment(fn);
  inferReactiveScopeVariables(fn);
  fn.aliasingEffects = functionEffects;
// ... (68 more lines)