From f41935a266ea5478621450c6cf7c7c4960c4abf9 Mon Sep 17 00:00:00 2001
From: Joe Savona <joesavona@fb.com>
Date: Wed, 21 Aug 2024 14:07:12 -0700
Subject: [PATCH] Update base for Update on "[compiler] Transitively freezing
 functions marks values as frozen, not effects"
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The fixture from the previous PR was getting inconsistent behavior because of the following:
1. Create an object in a useMemo
2. Create a callback in a useCallback, where the callback captures the object from (1) into a local object, then passes that local object into a logging method. We have to assume the logging method could modify the local object, and transitively, the object from (1).
3. Call the callback during render.
4. Pass the callback to JSX.

We correctly infer that the object from (1) is captured and modified in (2). However, in (4) we transitively freeze the callback. When transitively freezing functions we were previously doing two things: updating our internal abstract model of the program values to reflect the values as being frozen *and* also updating function operands to change their effects to freeze.

As the case above demonstrates, that can clobber over information about real potential mutability. The potential fix here is to only walk our abstract value model to mark values as frozen, but _not_ override operand effects. Conceptually, this is a forward data flow propagation — but walking backward to update effects is pushing information backwards in the algorithm. An alternative would be to mark that data was propagated backwards, and trigger another loop over the CFG to propagate information forward again given the updated effects. But the fix in this PR is more correct.

[ghstack-poisoned]
---
 .../src/Validation/ValidatePreservedManualMemoization.ts  | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/compiler/packages/babel-plugin-react-compiler/src/Validation/ValidatePreservedManualMemoization.ts b/compiler/packages/babel-plugin-react-compiler/src/Validation/ValidatePreservedManualMemoization.ts
index 3548b75236e59..7af4aaaccd7ab 100644
--- a/compiler/packages/babel-plugin-react-compiler/src/Validation/ValidatePreservedManualMemoization.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Validation/ValidatePreservedManualMemoization.ts
@@ -5,7 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {CompilerError, Effect, ErrorSeverity, printReactiveFunction} from '..';
+import {CompilerError, Effect, ErrorSeverity} from '..';
 import {
   DeclarationId,
   GeneratedSource,
@@ -23,11 +23,7 @@ import {
   ScopeId,
   SourceLocation,
 } from '../HIR';
-import {
-  printFunction,
-  printIdentifier,
-  printManualMemoDependency,
-} from '../HIR/PrintHIR';
+import {printIdentifier, printManualMemoDependency} from '../HIR/PrintHIR';
 import {eachInstructionValueOperand} from '../HIR/visitors';
 import {collectMaybeMemoDependencies} from '../Inference/DropManualMemoization';
 import {