include rt; // exact-size bounds: a heap block knows the n words new asked for (bits 32..62 of // p[-4]), not just its power-of-two block. rt.bnd(p, i, 1, 1) is 1 when p[i] is // outside: the same recipe every backend inlines in front of p[i]. struct P { int a; int b; int c; } struct Q { int a; } // n-1 inside, n outside, osize is n, and p[n-1] is usable int edge(int n) { word* p = rt.new(n); p[n - 1] = n; return rt.bnd(p, n - 1, 1, 1) * 100 + rt.bnd(p, n, 1, 1) * 10 + (rt.osize(p) == n) + (p[n - 1] == n) - 1; } int zero() { word* p = rt.new(0); return rt.bnd(p, 0, 1, 1) * 10 + rt.osize(p); } int bytes() { word* p = rt.new(3); return rt.bnd(p, 23, 1, 8) * 10 + rt.bnd(p, 24, 1, 8); } // 3 words are 24 bytes int where; int leaf() { P* a = rt.new(P); a.c = 3; where = (&a.a) as int; return a.c; } // a is recycled at the function's end // recycle: the next 1-word object reuses the 3-word block, with n = 1 int reuse() { Q* q = rt.new(Q); int same = where == ((&q.a) as int); return same * 1000 + rt.osize(q) * 100 + rt.bnd(q, 0, 1, 1) * 10 + rt.bnd(q, 1, 1, 1); } // grow: the items block is replaced by one with its own exact n (16 words for 9 ints) int grow() { int[?] d = rt.new(int[?], 0); int i = 0; word* h; word* p; while (i < 9) { d.push(i); i++; } h = &d[0]; p = h; return rt.osize(p) * 100 + rt.bnd(p, 15, 1, 1) * 10 + rt.bnd(p, 16, 1, 1); } // deep enough to grow the stacks: their segments are heap blocks the core allocates // (src/core/stack.h, src/js/tinyvm.ts) with n set too. after they go back, blocks reused // from them carry their own n. int deep(int k) { if (k == 0) return 0; return deep(k - 1) + 1; } fn main() { rt.put_n(edge(1)); rt.put_c(32); rt.put_n(edge(3)); rt.put_c(32); rt.put_n(edge(5)); rt.put_c(32); rt.put_n(edge(6)); rt.put_c(32); rt.put_n(edge(7)); rt.put_c(32); rt.put_n(edge(11)); rt.put_c(32); rt.put_n(edge(13)); rt.put_c(32); rt.put_n(edge(100)); rt.put_c(10); rt.put_n(zero()); rt.put_c(32); rt.put_n(bytes()); rt.put_c(10); leaf(); rt.put_n(reuse()); rt.put_c(10); rt.put_n(grow()); rt.put_c(10); rt.put_n(deep(200000)); rt.put_c(32); rt.put_n(edge(9)); rt.put_c(32); rt.put_n(edge(21)); rt.put_c(10); return 0; }