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Malte Ubl
6ddaa2a140
Two uses of the construction-only facts outside the collector (backend/immutability.ts): - Publication guards: a store into the constructor's own `this` that lies before the constructor's escape point, in a constructor no ancestor of which lets `this` escape and that is never invoked directly on an existing object, cannot target a published object. It loses its rc == SIZE_MAX guard and no longer seeds may-throw, so constructors that could only throw through guards lose their pending checks at every `new`. Storing `this` into one of its own fields does not expose it. - Borrowed reads: `x.f` holding an object, record, array or string is borrowed as a call argument, receiver or stable alias when `f` is construction-only and `x` is itself borrowable (unchanged local, borrowed parameter, or such a projection): nothing can replace and release it while `x` lives. Not inside constructors, which may still write their own fields. Module constants (immutable, not TDZ-checked, assigned at most once) are borrowable too. No object is frozen or marked at run time; publication errors, store order and reflection are unchanged. tsc-ts (e469e33), static: published-field guards 6,528 -> 4,462, sc_release calls 146,056 -> 129,756, sc_retain calls 26,215 -> 22,123, scr_arr_release 29,865 -> 25,617, binary 23.68 -> 22.96 MB (both commits). Self-check single-threaded, executed: guards 96.1M -> 60.8M, retains 273.5M -> 247.2M, releases 340.3M -> 314.0M. Linux sandbox, interleaved medians, both commits against perf/alloc-hugepages: single-threaded (6 runs) base new change Excalidraw 8.62 s 8.34 s -3.2% Playwright 7.83 s 7.71 s -1.5% tsc-ts self-check 4.36 s 4.22 s -3.0% tRPC 1.63 s 1.58 s -3.1% TypeORM 6.68 s 6.50 s -2.5% --checkers 8 (10 runs): -2.3% .. +0.7% (neutral) Runtime suite (--layouts=4 --runs=16): geomean -1.9%; ast-interp -4.4%, validate-errors -3.8%, regex-logs -1.7% faster, template-render +1.4% slower, the rest neutral; sizes unchanged.