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Joseph Savona
5d64f74211
Fixes #34108. If a scope ends with with a conditional where some/all branches exit via labeled break, we currently compile in a way that works but bypasses memoization. We end up with a shape like ```js let t0; label: { if (changed) { ... if (cond) { t0 = ...; break label; } // we don't save the output if the break happens! t0 = ...; $[0] = t0; } else { t0 = $[0]; } ``` The fix here is to update AlignReactiveScopesToBlockScopes to take account of breaks that don't go to the natural fallthrough. In this case, we take any active scopes and extend them to start at least as early as the label, and extend at least to the label fallthrough. Thus we produce the correct: ```js let t0; if (changed) { label: { ... if (cond) { t0 = ...; break label; } t0 = ...; } // now the break jumps here, and we cache the value $[0] = t0; } else { t0 = $[0]; } ``` --- [//]: # (BEGIN SAPLING FOOTER) Stack created with [Sapling](https://sapling-scm.com). Best reviewed with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34335). * #34347 * #34346 * #34343 * __->__ #34335
React Compiler
React Compiler is a compiler that optimizes React applications, ensuring that only the minimal parts of components and hooks will re-render when state changes. The compiler also validates that components and hooks follow the Rules of React.
More information about the design and architecture of the compiler are covered in the Design Goals.
More information about developing the compiler itself is covered in the Development Guide.