[compiler] Distinguish Alias/Assign effects #33385
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Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
This was referenced May 30, 2025
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Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. ghstack-source-id: ae2b35b Pull Request resolved: #33385
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
This was referenced Jun 4, 2025
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Jun 4, 2025
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. ghstack-source-id: ae2b35b Pull Request resolved: facebook/react#33385
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
This was referenced Jun 6, 2025
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment. An example of this is that for an unknown method call `const z = x.y()`, we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume that `z !== x`. This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias. [ghstack-poisoned]
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Stack from ghstack (oldest at bottom):
Alias was akward becuase it had a specific data flow / mutability relationship — direct mutations affect both sides - but also populated the output. We need the ability to express the aliasing dataflwo/mutability relationship w/o expressing actual assignment.
An example of this is that for an unknown method call
const z = x.y(), we want to express the Alias-style mutability relationship btw z and x (Muate(z) => Mutate(x)), but we want to assume thatz !== x.This ends up being really clean, the places that should use Assign are very obvious (LoadLocal, StoreLocal) and most places keep using Alias.