jolt.passes.inline was fully written but dormant — it fetched bodies via the
inline-ir host hook, which was a stub returning nil. Wire it up: run-passes stashes
each inline-eligible defn (single fixed arity) as its form is optimized, and
inline-ir hands the body back at call sites under --opt.
The catch was the ^double/^long coercion: an inlined fn drops its param-entry and
return coercion, so (work 3 4) on a ^double fn would return 25 instead of 25.0. New
:coerce IR node carries the coercion inside the spliced body — the inline pass wraps
a hinted param's arg and the return in :coerce, the back end lowers it
(exact->inexact / jolt->fx), and jolt.passes.numeric reads its :kind. So an inlined
call matches the called one and the body's fl*/fx* fast path still fires.
Only under --opt (closed world); the seed mint and -e don't inline, so selfhost and
the corpus are unaffected. test/chez/inline-test.ss 12/12 (make inline); full make
test green, 0 new corpus divergences.
Bench (hot loop, body is a ^double helper call): direct-link 500ms -> --opt
(inlined) 184ms = 2.7x, by eliminating the call + coercion wrappers and letting Chez
fuse the fl-ops unboxed. ~26x over the default dispatched build.
79fa22eeab