[compiler] Improve merging of scopes that invalidate together #34049
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Fixes remaining issue in #32261, where passing a previously useMemo()-d value to `Object.entries()` makes the compiler think the value is mutated and fail validatePreserveExistingMemo. While I was there I added Object.keys() and Object.values() too.
We try to merge consecutive reactive scopes that will always invalidate together, but there's one common case that isn't handled. ```js const y = [[x]]; ``` Here we'll create two consecutive scopes for the inner and outer array expressions. Because the input to the second scope is a temporary, they'll merge into one scope. But if we name the inner array, the merging stops: ```js const array = [x]; const y = [array]; ``` This is because the merging logic checks if all the dependencies of the second scope are outputs of the first scope, but doesn't account for renaming due to LoadLocal/StoreLocal. The fix is to track these temporaries.
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Fixes remaining issue in #32261, where passing a previously useMemo()-d value to `Object.entries()` makes the compiler think the value is mutated and fail validatePreserveExistingMemo. While I was there I added Object.keys() and Object.values() too. --- [//]: # (BEGIN SAPLING FOOTER) Stack created with [Sapling](https://sapling-scm.com). Best reviewed with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34047). * #34049 * __->__ #34047 * #34044
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Fixes remaining issue in #32261, where passing a previously useMemo()-d value to `Object.entries()` makes the compiler think the value is mutated and fail validatePreserveExistingMemo. While I was there I added Object.keys() and Object.values() too. --- [//]: # (BEGIN SAPLING FOOTER) Stack created with [Sapling](https://sapling-scm.com). Best reviewed with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34047). * #34049 * __->__ #34047 * #34044 DiffTrain build for [0860b9c](0860b9c)
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Fixes remaining issue in #32261, where passing a previously useMemo()-d value to `Object.entries()` makes the compiler think the value is mutated and fail validatePreserveExistingMemo. While I was there I added Object.keys() and Object.values() too. --- [//]: # (BEGIN SAPLING FOOTER) Stack created with [Sapling](https://sapling-scm.com). Best reviewed with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34047). * #34049 * __->__ #34047 * #34044 DiffTrain build for [0860b9c](0860b9c)
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We try to merge consecutive reactive scopes that will always invalidate together, but there's one common case that isn't handled. ```js const y = [[x]]; ``` Here we'll create two consecutive scopes for the inner and outer array expressions. Because the input to the second scope is a temporary, they'll merge into one scope. But if we name the inner array, the merging stops: ```js const array = [x]; const y = [array]; ``` This is because the merging logic checks if all the dependencies of the second scope are outputs of the first scope, but doesn't account for renaming due to LoadLocal/StoreLocal. The fix is to track these temporaries. --- [//]: # (BEGIN SAPLING FOOTER) Stack created with [Sapling](https://sapling-scm.com). Best reviewed with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34049). * __->__ #34049 * #34047 * #34044 DiffTrain build for [ddf8bc3](ddf8bc3)
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…ok#34049) We try to merge consecutive reactive scopes that will always invalidate together, but there's one common case that isn't handled. ```js const y = [[x]]; ``` Here we'll create two consecutive scopes for the inner and outer array expressions. Because the input to the second scope is a temporary, they'll merge into one scope. But if we name the inner array, the merging stops: ```js const array = [x]; const y = [array]; ``` This is because the merging logic checks if all the dependencies of the second scope are outputs of the first scope, but doesn't account for renaming due to LoadLocal/StoreLocal. The fix is to track these temporaries. --- [//]: # (BEGIN SAPLING FOOTER) Stack created with [Sapling](https://sapling-scm.com). Best reviewed with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34049). * __->__ facebook#34049 * facebook#34047 * facebook#34044 DiffTrain build for [ddf8bc3](facebook@ddf8bc3)
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…ok#34049) We try to merge consecutive reactive scopes that will always invalidate together, but there's one common case that isn't handled. ```js const y = [[x]]; ``` Here we'll create two consecutive scopes for the inner and outer array expressions. Because the input to the second scope is a temporary, they'll merge into one scope. But if we name the inner array, the merging stops: ```js const array = [x]; const y = [array]; ``` This is because the merging logic checks if all the dependencies of the second scope are outputs of the first scope, but doesn't account for renaming due to LoadLocal/StoreLocal. The fix is to track these temporaries. --- [//]: # (BEGIN SAPLING FOOTER) Stack created with [Sapling](https://sapling-scm.com). Best reviewed with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34049). * __->__ facebook#34049 * facebook#34047 * facebook#34044 DiffTrain build for [ddf8bc3](facebook@ddf8bc3)
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We try to merge consecutive reactive scopes that will always invalidate together, but there's one common case that isn't handled.
Here we'll create two consecutive scopes for the inner and outer array expressions. Because the input to the second scope is a temporary, they'll merge into one scope.
But if we name the inner array, the merging stops:
This is because the merging logic checks if all the dependencies of the second scope are outputs of the first scope, but doesn't account for renaming due to LoadLocal/StoreLocal. The fix is to track these temporaries.
Stack created with Sapling. Best reviewed with ReviewStack.