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binary search the dispatch lookup when ranges are irregular - #35
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This was referenced Oct 9, 2026
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40637c4 splits llvm ranges at every function boundary, so the linear dispatch lookup grew from 2 checks to ~7000 per dispatch. emit a sorted table and binary search it once there are more than 16 runs.
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40637c4 started splitting llvm ranges at function boundaries. the default dispatch lookup only collapses equal-stride runs, so
dolrecomp_find_originalwent from 2 checks to ~7000 sequential ones, and it runs on every return to the runner. llvm modules ended up 7-30x slower than the c backend, and mkddrace.savhung.this emits a sorted table and binary searches it once there are more than 16 runs. a small number of runs keeps the existing linear form. overlapping ranges also stay linear to keep first-match order. a coverage guard in the old
address >= ... && address < ...form rejects out-of-range addresses first, and keeps module-table generators that scrape it working.frames in 20s, recompcore runtime:
added tests in
test_dispatch.c.