Keep VaryPath monomorphic by making isRootParam required#96122
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VaryPath nodes are created and traversed on a very hot path in the segment cache, so their object shape matters for performance. isRootParam was optional: most nodes left it undefined while a few set it, so nodes had inconsistent shapes. That prevents V8 from sharing a single hidden class across them and deopts the cache hot paths. Make isRootParam a required boolean, always set (false for structural and search param nodes), so every node has the same shape and these paths stay monomorphic.
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VaryPathnodes are created and traversed on a very hot path in the segment cache, so their object shape matters for performance.isRootParamwas optional: most nodes left it undefined while a few set it, so nodes had inconsistent shapes. That prevents V8 from sharing a single hidden class across them and deopts the cache hot paths.This makes
isRootParama required boolean, always set (falsefor structural and search param nodes), so everyVaryPathnode has the same shape and these paths stay monomorphic.