dellingr 0.4.0

An embeddable, pure-Rust Lua VM with precise instruction-cost accounting
Documentation 
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-- Probe: sustained live heap plus per-iteration garbage, so that collections
-- have real marking work to do rather than sweeping a nearly empty heap.
-- `retained` stays reachable for the whole run, so every mark pass walks it;
-- the loop body then churns short-lived tables and closures on top.
-- Two things are measurable here: the cost of the mark walk itself (today a
-- recursive mark_children), and upvalue-pool growth - UpvaluePool::alloc only
-- ever grows, so each closure-with-captures created here consumes a pool slot
-- that is never reclaimed.
-- Compare against alloc/closure.lua, which churns closures against an almost
-- empty heap and so barely exercises marking.

local retained = {}
for i = 1, 200 do
    retained[i] = {
        id = i,
        tag = "node",
        kids = { i, i + 1, i + 2 },
    }
end

function _bench()
    local sink = 0
    for i = 1, 200 do
        local tmp = { a = i, b = i + 1 }
        local n = i
        local f = function()
            return n + tmp.a
        end
        sink = sink + f()
    end
    return sink
end

for i = 1, 400 do _bench() end
print("alloc/gc_churn: true")