Eliminate exception-based hashtable lookups in solver hot paths#1976

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Copilot wants to merge 6 commits intomasterfrom

copilot/audit-performance-bottlenecks

Commits on Apr 1, 2026

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Copilot
authored
Replace try/Not_found with find_default in solvers; use List.concat_map in pat_exp.ml

Copilot
and
michael-schwarz
authored
Also replace try/Not_found with find_default in sLR.ml

Copilot
and
michael-schwarz
authored
Revert find_default to try/Not_found where default is S.Dom.bot()

Copilot
and
michael-schwarz
authored
Revert List.concat_map change in vendor/ppx_easy_deriving/pat_exp.ml

Copilot
and
michael-schwarz
authored
Define find_default_delayed helper and replace S.Dom.bot() try/Not_found patterns

Copilot
and
michael-schwarz
authored