| # buf0 = NODE_HEADER_SIZE, # buf1 = nd.alignedsize, n0 = n1 + nd.alignedsize, n0 < NODE_HEADER_SIZE + nd.alignedsize, is-aligned(n0, NODE_HEADER_SIZE), is-encoded(nd, subarray(buf1, 0, node-size-headerless(nd))), is-encoded(nodeheader(node-size-headerless(nd), false), buf0), nd.alignedsize ≤ n0 ⊦ ∃ buf2, buf3. buf0 + buf1 + subarray(validtrailer, 0, n1) = buf2 + buf3 ∧ # buf2 = NODE_HEADER_SIZE ∧ (is-garbage-header(buf2) ∨ (∃ ndhd. is-encoded(ndhd, buf2) ∧ # buf3 ≤ align↑(ndhd.size, 2 * NODE_HEADER_SIZE))) |
# buf0 = NODE_HEADER_SIZE, # buf1 = nd.alignedsize, is-encoded(nd, subarray(buf1, 0, node-size-headerless(nd))), is-encoded(nodeheader(node-size-headerless(nd), false), buf0) ⊦ ∃ buf, buf2. buf0 + buf1 = buf + buf2 ∧ # buf = NODE_HEADER_SIZE ∧ (is-garbage-header(buf) ∨ (∃ ndhd. is-encoded(ndhd, buf) ∧ # buf2 ≤ align↑(ndhd.size, 2 * NODE_HEADER_SIZE)))
Used simplifier rules: append-a: ⊦ (buf + buf0) + buf1 = buf + buf0 + buf1; from specification array-splice[buffer]% ⊦ buf + mkbuf(0) = buf; (s)% ⊦ subarray(buf, n, 0) = mkbuf(0); (s)%n ≠ 0 ⊦ is-aligned(0, n); (s)%m ≠ 0 ⊦ is-aligned(n, m) → (n < m ↔ n = 0); (s)% ⊦ m + n < m + n0 ↔ n < n0; (s)%m ≠ 0, is-aligned(n1, m) ⊦ is-aligned(n0 + n1, m) ↔ is-aligned(n0, m); (s)% ⊦ is-aligned(nd.alignedsize, NODE_HEADER_SIZE); (s)% ⊦ NODE_HEADER_SIZE ≠ 0; (s)%c: ⊦ m + n = n + m; from specification nat-basic%a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic% ⊦ m ≤ m + n; (s)