Add trampoline pass for stack-safe (mutual) TRMC#900
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…rsion Implements Core/Trampoline.hs: converts tail-recursive and mutually tail-recursive function SCCs -- including recursion modulo cons (e.g. zip-even/zip-odd) -- into a stack-safe form. SCC members are fused directly into a single self-recursive @run driver over a generated Bounce value type (one @Call-* constructor per member; tail and modulo-cons calls are redirected in place to @run(@Call-*(args)), preserving surrounding constructor structure), with thin per-member wrappers `fi(args) = @run(@Call-*(args))`. This collapses N-way mutual recursion into 1-way self-recursion and routes the result through CTail's existing TRMC machinery for free -- trampoline now runs before ctail in the optimization pipeline so the fused @run becomes a context/hole-passing loop with no stack growth for reference-typed results. Adds the optTrampoline flag (enabled by default), wires the pass into coreOptimize, and adds tests. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Implements Core/Trampoline.hs: converts tail-recursive and mutually tail-recursive function SCCs -- including recursion modulo cons (e.g. zip-even/zip-odd) -- into a stack-safe form. SCC members are fused directly into a single self-recursive @run driver over a generated Bounce value type (one @Call-* constructor per member; tail and modulo-cons calls are redirected in place to @run(@Call-*(args)), preserving surrounding constructor structure), with thin per-member wrappers
fi(args) = @run(@Call-*(args)). This collapses N-way mutual recursion into 1-way self-recursion and routes the result through CTail's existing TRMC machinery for free -- trampoline now runs before ctail in the optimization pipeline so the fused @run becomes a context/hole-passing loop with no stack growth for reference-typed results.Adds the optTrampoline flag (enabled by default), wires the pass into coreOptimize, and adds tests.