From 148aa1901fec75daeebce2b003c4ca11661a6ea7 Mon Sep 17 00:00:00 2001
From: Joe Savona <joesavona@fb.com>
Date: Thu, 29 May 2025 17:30:51 -0700
Subject: [PATCH] [compiler] Receiver is mutate? for functions wo signatures

[ghstack-poisoned]
---
 .../Inference/InferMutationAliasingEffects.ts | 17 +++++-
 .../new-mutability/set-add-mutate.expect.md   | 54 +++++++++++++++++++
 .../compiler/new-mutability/set-add-mutate.js | 11 ++++
 3 files changed, 80 insertions(+), 2 deletions(-)
 create mode 100644 compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/set-add-mutate.expect.md
 create mode 100644 compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/set-add-mutate.js

diff --git a/compiler/packages/babel-plugin-react-compiler/src/Inference/InferMutationAliasingEffects.ts b/compiler/packages/babel-plugin-react-compiler/src/Inference/InferMutationAliasingEffects.ts
index 475319830373..bb246671cb92 100644
--- a/compiler/packages/babel-plugin-react-compiler/src/Inference/InferMutationAliasingEffects.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Inference/InferMutationAliasingEffects.ts
@@ -519,6 +519,9 @@ function applyEffect(
             )
           : null;
       if (signatureEffects != null) {
+        if (DEBUG) {
+          console.log('apply aliasing signature effects');
+        }
         for (const signatureEffect of signatureEffects) {
           applyEffect(
             state,
@@ -530,6 +533,9 @@ function applyEffect(
           );
         }
       } else if (effect.signature != null) {
+        if (DEBUG) {
+          console.log('apply legacy signature effects');
+        }
         const legacyEffects = computeEffectsForLegacySignature(
           state,
           effect.signature,
@@ -548,6 +554,9 @@ function applyEffect(
           );
         }
       } else {
+        if (DEBUG) {
+          console.log('default effects');
+        }
         applyEffect(
           state,
           {
@@ -567,7 +576,7 @@ function applyEffect(
          * - All operands are captured into (but not directly aliased as)
          *   every other argument.
          */
-        for (const arg of [effect.function, ...effect.args]) {
+        for (const arg of [effect.receiver, effect.function, ...effect.args]) {
           const operand = arg.kind === 'Identifier' ? arg : arg.place;
           if (operand !== effect.function || effect.mutatesFunction) {
             applyEffect(
@@ -599,7 +608,11 @@ function applyEffect(
             aliased,
             effects,
           );
-          for (const otherArg of [effect.function, ...effect.args]) {
+          for (const otherArg of [
+            effect.receiver,
+            effect.function,
+            ...effect.args,
+          ]) {
             const other =
               otherArg.kind === 'Identifier' ? otherArg : otherArg.place;
             if (other === arg) {
diff --git a/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/set-add-mutate.expect.md b/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/set-add-mutate.expect.md
new file mode 100644
index 000000000000..955c4e070579
--- /dev/null
+++ b/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/set-add-mutate.expect.md
@@ -0,0 +1,54 @@
+
+## Input
+
+```javascript
+// @enableNewMutationAliasingModel
+function useHook({el1, el2}) {
+  const s = new Set();
+  const arr = makeArray(el1);
+  s.add(arr);
+  // Mutate after store
+  arr.push(el2);
+
+  s.add(makeArray(el2));
+  return s.size;
+}
+
+```
+
+## Code
+
+```javascript
+import { c as _c } from "react/compiler-runtime"; // @enableNewMutationAliasingModel
+function useHook(t0) {
+  const $ = _c(5);
+  const { el1, el2 } = t0;
+  let s;
+  if ($[0] !== el1 || $[1] !== el2) {
+    s = new Set();
+    const arr = makeArray(el1);
+    s.add(arr);
+
+    arr.push(el2);
+    let t1;
+    if ($[3] !== el2) {
+      t1 = makeArray(el2);
+      $[3] = el2;
+      $[4] = t1;
+    } else {
+      t1 = $[4];
+    }
+    s.add(t1);
+    $[0] = el1;
+    $[1] = el2;
+    $[2] = s;
+  } else {
+    s = $[2];
+  }
+  return s.size;
+}
+
+```
+      
+### Eval output
+(kind: exception) Fixture not implemented
\ No newline at end of file
diff --git a/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/set-add-mutate.js b/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/set-add-mutate.js
new file mode 100644
index 000000000000..3afbd93f84b1
--- /dev/null
+++ b/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/set-add-mutate.js
@@ -0,0 +1,11 @@
+// @enableNewMutationAliasingModel
+function useHook({el1, el2}) {
+  const s = new Set();
+  const arr = makeArray(el1);
+  s.add(arr);
+  // Mutate after store
+  arr.push(el2);
+
+  s.add(makeArray(el2));
+  return s.size;
+}