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Sathya Gunasekaran
00d4a69459
Previously useMemo inlining created a new StoreLocal assignment (not
reassignment!) instruction for every return value. This breaks when the return
is inside a block (like an if-block) as the scope is tied to the block.
For example: ``` let x = useMemo(() => { if (...) { return { ... }; } })
``` would become: ``` if (...) { const temp = { ... }; } const x = temp; ```
This PR instead changes the inlining to declare a temporary in the function
prologue and then reassign values to it when replacing return statements.
``` let x = useMemo(() => { if (...) { return { ... }; } }) ```
becomes
``` let temp; if (...) { temp = { ... }; } const x = temp; ```