Trie index: storing existence of indices (04be35ec) · Commits · 戴 / Bird

lib/tindex.c

+34 −3

Original line number	Diff line number	Diff line
		@@ -26,6 +26,7 @@ union tindex_data {

		struct tindex {
		union tindex_data *index_data;
		u64 *exists;
		pool *p;
		struct idm idm;
		u8 unit_size;
		@@ -40,6 +41,7 @@ tindex_new(pool *p)
		ti->unit_size = TI_MIN_UNIT_SIZE;
		ti->address_size = TI_MIN_ADDRESS_SIZE;
		ti->index_data = mb_allocz(p, ti->unit_size * (1 << ti->address_size));
		ti->exists = mb_allocz(p, (1 << (ti->address_size - 3)));
		idm_init(&(ti->idm), p, (1 << (ti->address_size - 5)), (1 << ti->address_size));
		u32 rootnode = idm_alloc(&(ti->idm));
		ASSERT(rootnode == 1);
		@@ -234,6 +236,24 @@ static inline uint tindex_input_bits(const u64 bits_in, const uint blen, uint
		return ilen;
		}

		static inline void
		tindex_exists_set(const struct tindex *ti, const u64 idx)
		{
		ti->exists[idx / 64] \|= (1ULL << (idx % 64));
		}

		static inline u64
		tindex_exists(const struct tindex *ti, const u64 idx)
		{
		return (ti->exists[idx / 64] & (1ULL << (idx % 64)));
		}

		static inline void
		tindex_exists_clear(const struct tindex *ti, const u64 idx)
		{
		ti->exists[idx / 64] &= ~(1ULL << (idx % 64));
		}

		const char dump_indent[] = " ";
		#define INDENT (dump_indent + sizeof(dump_indent) - depth - 1)

		@@ -263,7 +283,7 @@ _tindex_dump(const struct tindex *ti, u64 idx, uint depth, uint bit)
		if (depth)
		dlen++;

		debug("%s0x%x/%u (%lu)\n", INDENT, data, dlen, idx);
		debug("%s0x%x/%u (%lu %c)\n", INDENT, data, dlen, idx, tindex_exists(ti, idx) ? '*' : ' ');
		u64 left = tindex_left(ti, idx, usize, asize, addrmask);
		if (left)
		_tindex_dump(ti, left, depth+1, 0);
		@@ -325,11 +345,19 @@ tindex_find(struct tindex ti, const u64 bits_in, const uint blen, const int cr
		ilen = tindex_input_bits(bits_in, blen, &bpos, 1, &bits);

		/* No more bits, we're done */
		if (!ilen)
		if (!ilen) {
		/* Existence bits fiddling */
		if (create)
		tindex_exists_set(ti, idx);
		else if (!tindex_exists(ti, idx))
		return 0;

		return idx;
		}

		/* Just one bit, to be sure */
		ASSERT(bits < 2);
		ASSERT(ilen == 1);

		/* Go left or right? */
		u64 nidx = bits ? tindex_right(ti, idx, usize, asize, addrmask) : tindex_left(ti, idx, usize, asize, addrmask);
		@@ -410,9 +438,11 @@ tindex_find(struct tindex ti, const u64 bits_in, const uint blen, const int cr
		/* Grow there a branch if it has to be grown, otherwise return */
		if (split)
		break;
		else
		else {
		tindex_exists_set(ti, midx);
		return midx;
		}
		}

		/* Growing a new branch */
		while (1) {
		@@ -426,6 +456,7 @@ tindex_find(struct tindex ti, const u64 bits_in, const uint blen, const int cr
		/* End of input data */
		if ((ilen < dsize - 1) \|\| !tindex_input_bits(bits_in, blen, &bpos, 1, &dataright)) {
		tindex_put(ti, idx, usize, asize, dsize, dshift, data, ilen, 0, 0, uidx);
		tindex_exists_set(ti, idx);
		return idx;
		}

lib/tindex.h

+1 −15

Original line number	Diff line number	Diff line
		@@ -10,21 +10,7 @@
		#include "nest/bird.h"

		/**
		* tindex_bitcheck() callback is called by tindex_find() repeatedly
		* to get input bits as needed. Maximal number of bits is
		* given in @len; it shall be replaced the actual number of bits
		* returned. The bits shall be returned in LSB of the return value.
		* If (and only if) no bits are remaining, @len shall be changed,
		* otherwise the callee must always return full bit string.
		*
		* This is intended to be implemented as a nested function in
		* a library call using this tree index.
		**/

		typedef u64 (tindex_bitcheck)(u8 len);

		/**
		* Allocate a new tr[ei]e index from the given pool
		* Allocate a new trie index from the given pool
		* @p: pool to allocate from
		*
		* Returns the allocated tindex structure.

lib/tindex_test.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -19,6 +19,7 @@ struct test_trie {

		static inline void test_trie_add(struct test_trie *tt, u64 data) {
		u64 idx = tindex_find(tt->ti, &data, 64, 1);
		bt_assert(idx > 0);

		u64 nlen = tt->len;
		while (idx > nlen)
		@@ -57,7 +58,7 @@ t_simple(void)
		}

		for (u64 i = 0; i < 20; i++)
		bt_assert(test_trie_get(&tt, i) == 1);
		bt_assert_msg(test_trie_get(&tt, i) == 1, "Index %lu shall be in trie", i);

		return 1;
		}

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