| # buf0 = EB_PAGE_SIZE, buf + emptypage = buf0 + buf1, is-aligned(# buf, EB_PAGE_SIZE), is-encoded(nx0, buf1), is-encoded(rnode(m), buf0), EB_PAGE_SIZE ≤ # buf, # buf ≠ 0 → buf = buf2 + buf3 ∧ # buf2 = EB_PAGE_SIZE, ∀ buf2. ¬ is-aligned(# buf2, EB_PAGE_SIZE) ∨ ¬ is-encoded(nx0, buf2 + emptypage) ⊦ |
# buf0 = EB_PAGE_SIZE, # buf2 = EB_PAGE_SIZE, (buf2 + buf3) + emptypage = buf0 + buf1, is-aligned(# buf3, EB_PAGE_SIZE), is-encoded(rnode(m), buf0), is-encoded(nx0, buf1), ∀ buf2. ¬ is-aligned(# buf2, EB_PAGE_SIZE) ∨ ¬ is-encoded(nx0, buf2 + emptypage) ⊦
Used simplifier rules: ⊦ EB_PAGE_SIZE + n = 0 ↔ false; (s)%c: ⊦ m + n = n + m; from specification nat-basic%a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic%m ≠ 0, is-aligned(n1, m) ⊦ is-aligned(n0 + n1, m) ↔ is-aligned(n0, m); (s)%n ≠ 0 ⊦ is-aligned(n, n); (s)%append-a: ⊦ (buf + buf0) + buf1 = buf + buf0 + buf1; from specification array-splice[buffer]% ⊦ #(buf + buf0) = # buf + # buf0; (s)%m ≠ 0 ⊦ is-aligned(n, m) → (m ≤ n ↔ n ≠ 0); (s)% ⊦ EB_PAGE_SIZE ≠ 0; (s)