| 1 | /** |
| 2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
| 3 | * |
| 4 | * This source code is licensed under the MIT license found in the |
| 5 | * LICENSE file in the root directory of this source tree. |
| 6 | */ |
| 7 | |
| 8 | import {CompilerError} from '../CompilerError'; |
| 9 | import {Effect, HIRFunction, IdentifierId, makeInstructionId} from '../HIR'; |
| 10 | import {deadCodeElimination} from '../Optimization'; |
| 11 | import {inferReactiveScopeVariables} from '../ReactiveScopes'; |
| 12 | import {rewriteInstructionKindsBasedOnReassignment} from '../SSA'; |
| 13 | import {assertExhaustive} from '../Utils/utils'; |
| 14 | import {inferMutationAliasingEffects} from './InferMutationAliasingEffects'; |
| 15 | import {inferMutationAliasingRanges} from './InferMutationAliasingRanges'; |
| 16 | |
| 17 | export default function analyseFunctions(func: HIRFunction): void { |
| 18 | for (const [_, block] of func.body.blocks) { |
| 19 | for (const instr of block.instructions) { |
| 20 | switch (instr.value.kind) { |
| 21 | case 'ObjectMethod': |
| 22 | case 'FunctionExpression': { |
| 23 | lowerWithMutationAliasing(instr.value.loweredFunc.func); |
| 24 | |
| 25 | /** |
| 26 | * Reset mutable range for outer inferReferenceEffects |
| 27 | */ |
| 28 | for (const operand of instr.value.loweredFunc.func.context) { |
| 29 | /** |
| 30 | * NOTE: inferReactiveScopeVariables makes identifiers in the scope |
| 31 | * point to the *same* mutableRange instance. Resetting start/end |
| 32 | * here is insufficient, because a later mutation of the range |
| 33 | * for any one identifier could affect the range for other identifiers. |
| 34 | */ |
| 35 | operand.identifier.mutableRange = { |
| 36 | start: makeInstructionId(0), |
| 37 | end: makeInstructionId(0), |
| 38 | }; |
| 39 | operand.identifier.scope = null; |
| 40 | } |
| 41 | break; |
| 42 | } |
| 43 | } |
| 44 | } |
| 45 | } |
| 46 | } |
| 47 | |
| 48 | function lowerWithMutationAliasing(fn: HIRFunction): void { |
| 49 | /** |
| 50 | * Phase 1: similar to lower(), but using the new mutation/aliasing inference |
| 51 | */ |
| 52 | analyseFunctions(fn); |
| 53 | inferMutationAliasingEffects(fn, {isFunctionExpression: true}); |
| 54 | deadCodeElimination(fn); |
| 55 | const functionEffects = inferMutationAliasingRanges(fn, { |
| 56 | isFunctionExpression: true, |
| 57 | }); |
| 58 | rewriteInstructionKindsBasedOnReassignment(fn); |
| 59 | inferReactiveScopeVariables(fn); |
| 60 | fn.aliasingEffects = functionEffects; |
| 61 | |
| 62 | /** |
| 63 | * Phase 2: populate the Effect of each context variable to use in inferring |
| 64 | * the outer function. For example, InferMutationAliasingEffects uses context variable |
| 65 | * effects to decide if the function may be mutable or not. |
| 66 | */ |
| 67 | const capturedOrMutated = new Set<IdentifierId>(); |
| 68 | for (const effect of functionEffects) { |
| 69 | switch (effect.kind) { |
| 70 | case 'Assign': |
| 71 | case 'Alias': |
| 72 | case 'Capture': |
| 73 | case 'CreateFrom': |
| 74 | case 'MaybeAlias': { |
| 75 | capturedOrMutated.add(effect.from.identifier.id); |
| 76 | break; |
| 77 | } |
| 78 | case 'Apply': { |
| 79 | CompilerError.invariant(false, { |
| 80 | reason: `[AnalyzeFunctions] Expected Apply effects to be replaced with more precise effects`, |
| 81 | loc: effect.function.loc, |
| 82 | }); |
| 83 | } |
| 84 | case 'Mutate': |
| 85 | case 'MutateConditionally': |
| 86 | case 'MutateTransitive': |
| 87 | case 'MutateTransitiveConditionally': { |
| 88 | capturedOrMutated.add(effect.value.identifier.id); |
| 89 | break; |
| 90 | } |
| 91 | case 'Impure': |
| 92 | case 'Render': |
| 93 | case 'MutateFrozen': |
| 94 | case 'MutateGlobal': |
| 95 | case 'CreateFunction': |
| 96 | case 'Create': |
| 97 | case 'Freeze': |
| 98 | case 'ImmutableCapture': { |
| 99 | // no-op |
| 100 | break; |
| 101 | } |
| 102 | default: { |
| 103 | assertExhaustive( |
| 104 | effect, |
| 105 | `Unexpected effect kind ${(effect as any).kind}`, |
| 106 | ); |
| 107 | } |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | for (const operand of fn.context) { |
| 112 | if ( |
| 113 | capturedOrMutated.has(operand.identifier.id) || |
| 114 | operand.effect === Effect.Capture |
| 115 | ) { |
| 116 | operand.effect = Effect.Capture; |
| 117 | } else { |
| 118 | operand.effect = Effect.Read; |
| 119 | } |
| 120 | } |
| 121 | |
| 122 | fn.env.logger?.debugLogIRs?.({ |
| 123 | kind: 'hir', |
| 124 | name: 'AnalyseFunction (inner)', |
| 125 | value: fn, |
| 126 | }); |
| 127 | } |