From 58a3ca3b47f6a51cea48ea95ded26c9887baca38 Mon Sep 17 00:00:00 2001
From: Mofei Zhang <feifei0@meta.com>
Date: Mon, 30 Sep 2024 12:24:21 -0400
Subject: [PATCH] [compiler][hir-rewrite] Cleanup Identifier -> IdentifierId

Since removing ExitSSA, Identifier and IdentifierId should mean the same thing

ghstack-source-id: 076cacbe8360e716b0555088043502823f9ee72e
Pull Request resolved: https://github.com/facebook/react/pull/31034
---
 .../src/HIR/CollectHoistablePropertyLoads.ts  | 66 ++-----------------
 .../src/HIR/PropagateScopeDependenciesHIR.ts  | 49 +++++++++++++-
 2 files changed, 53 insertions(+), 62 deletions(-)

diff --git a/compiler/packages/babel-plugin-react-compiler/src/HIR/CollectHoistablePropertyLoads.ts b/compiler/packages/babel-plugin-react-compiler/src/HIR/CollectHoistablePropertyLoads.ts
index ff50113b6660c..4f642e57a65f3 100644
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/CollectHoistablePropertyLoads.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/CollectHoistablePropertyLoads.ts
@@ -9,7 +9,6 @@ import {
   Identifier,
   IdentifierId,
   InstructionId,
-  Place,
   ReactiveScopeDependency,
   ScopeId,
 } from './HIR';
@@ -88,61 +87,6 @@ export type BlockInfo = {
   assumedNonNullObjects: ReadonlySet<PropertyLoadNode>;
 };
 
-export function getProperty(
-  object: Place,
-  propertyName: string,
-  temporaries: ReadonlyMap<IdentifierId, ReactiveScopeDependency>,
-): ReactiveScopeDependency {
-  /*
-   * (1) Get the base object either from the temporary sidemap (e.g. a LoadLocal)
-   * or a deep copy of an existing property dependency.
-   *  Example 1:
-   *    $0 = LoadLocal x
-   *    $1 = PropertyLoad $0.y
-   *  getProperty($0, ...) -> resolvedObject = x, resolvedDependency = null
-   *
-   *  Example 2:
-   *    $0 = LoadLocal x
-   *    $1 = PropertyLoad $0.y
-   *    $2 = PropertyLoad $1.z
-   *  getProperty($1, ...) -> resolvedObject = null, resolvedDependency = x.y
-   *
-   *  Example 3:
-   *    $0 = Call(...)
-   *    $1 = PropertyLoad $0.y
-   *  getProperty($0, ...) -> resolvedObject = null, resolvedDependency = null
-   */
-  const resolvedDependency = temporaries.get(object.identifier.id);
-
-  /**
-   * (2) Push the last PropertyLoad
-   * TODO(mofeiZ): understand optional chaining
-   */
-  let property: ReactiveScopeDependency;
-  if (resolvedDependency == null) {
-    property = {
-      identifier: object.identifier,
-      path: [{property: propertyName, optional: false}],
-    };
-  } else {
-    property = {
-      identifier: resolvedDependency.identifier,
-      path: [
-        ...resolvedDependency.path,
-        {property: propertyName, optional: false},
-      ],
-    };
-  }
-  return property;
-}
-
-export function resolveTemporary(
-  place: Place,
-  temporaries: ReadonlyMap<IdentifierId, Identifier>,
-): Identifier {
-  return temporaries.get(place.identifier.id) ?? place.identifier;
-}
-
 /**
  * Tree data structure to dedupe property loads (e.g. a.b.c)
  * and make computing sets intersections simpler.
@@ -152,7 +96,7 @@ type RootNode = {
   parent: null;
   // Recorded to make later computations simpler
   fullPath: ReactiveScopeDependency;
-  root: Identifier;
+  root: IdentifierId;
 };
 
 type PropertyLoadNode =
@@ -164,18 +108,18 @@ type PropertyLoadNode =
   | RootNode;
 
 class Tree {
-  roots: Map<Identifier, RootNode> = new Map();
+  roots: Map<IdentifierId, RootNode> = new Map();
 
   getOrCreateRoot(identifier: Identifier): PropertyLoadNode {
     /**
      * Reads from a statically scoped variable are always safe in JS,
      * with the exception of TDZ (not addressed by this pass).
      */
-    let rootNode = this.roots.get(identifier);
+    let rootNode = this.roots.get(identifier.id);
 
     if (rootNode === undefined) {
       rootNode = {
-        root: identifier,
+        root: identifier.id,
         properties: new Map(),
         fullPath: {
           identifier,
@@ -183,7 +127,7 @@ class Tree {
         },
         parent: null,
       };
-      this.roots.set(identifier, rootNode);
+      this.roots.set(identifier.id, rootNode);
     }
     return rootNode;
   }
diff --git a/compiler/packages/babel-plugin-react-compiler/src/HIR/PropagateScopeDependenciesHIR.ts b/compiler/packages/babel-plugin-react-compiler/src/HIR/PropagateScopeDependenciesHIR.ts
index 4c7dac004d80a..1fe218c352818 100644
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/PropagateScopeDependenciesHIR.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/PropagateScopeDependenciesHIR.ts
@@ -20,7 +20,6 @@ import {
 import {
   BlockInfo,
   collectHoistablePropertyLoads,
-  getProperty,
 } from './CollectHoistablePropertyLoads';
 import {
   ScopeBlockTraversal,
@@ -220,6 +219,54 @@ function collectTemporariesSidemap(
   return temporaries;
 }
 
+function getProperty(
+  object: Place,
+  propertyName: string,
+  temporaries: ReadonlyMap<IdentifierId, ReactiveScopeDependency>,
+): ReactiveScopeDependency {
+  /*
+   * (1) Get the base object either from the temporary sidemap (e.g. a LoadLocal)
+   * or a deep copy of an existing property dependency.
+   *  Example 1:
+   *    $0 = LoadLocal x
+   *    $1 = PropertyLoad $0.y
+   *  getProperty($0, ...) -> resolvedObject = x, resolvedDependency = null
+   *
+   *  Example 2:
+   *    $0 = LoadLocal x
+   *    $1 = PropertyLoad $0.y
+   *    $2 = PropertyLoad $1.z
+   *  getProperty($1, ...) -> resolvedObject = null, resolvedDependency = x.y
+   *
+   *  Example 3:
+   *    $0 = Call(...)
+   *    $1 = PropertyLoad $0.y
+   *  getProperty($0, ...) -> resolvedObject = null, resolvedDependency = null
+   */
+  const resolvedDependency = temporaries.get(object.identifier.id);
+
+  /**
+   * (2) Push the last PropertyLoad
+   * TODO(mofeiZ): understand optional chaining
+   */
+  let property: ReactiveScopeDependency;
+  if (resolvedDependency == null) {
+    property = {
+      identifier: object.identifier,
+      path: [{property: propertyName, optional: false}],
+    };
+  } else {
+    property = {
+      identifier: resolvedDependency.identifier,
+      path: [
+        ...resolvedDependency.path,
+        {property: propertyName, optional: false},
+      ],
+    };
+  }
+  return property;
+}
+
 type Decl = {
   id: InstructionId;
   scope: Stack<ReactiveScope>;