vendor/libpcap/1.26

1 files changed, 0 insertions, 2090 deletions

diff --git a/contrib/libpcap/optimize.c b/contrib/libpcap/optimize.c
deleted file mode 100644
index 928cc1cfdeec..000000000000
--- a/contrib/libpcap/optimize.c
+++ /dev/null
@@ -1,2090 +0,0 @@
-/*
- * Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994, 1995, 1996
- *	The Regents of the University of California.  All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that: (1) source code distributions
- * retain the above copyright notice and this paragraph in its entirety, (2)
- * distributions including binary code include the above copyright notice and
- * this paragraph in its entirety in the documentation or other materials
- * provided with the distribution, and (3) all advertising materials mentioning
- * features or use of this software display the following acknowledgement:
- * ``This product includes software developed by the University of California,
- * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
- * the University nor the names of its contributors may be used to endorse
- * or promote products derived from this software without specific prior
- * written permission.
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
- * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
- *
- *  Optimization module for tcpdump intermediate representation.
- */
-#ifndef lint
-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/libpcap/optimize.c,v 1.61 1999/10/19 15:18:30 itojun Exp $ (LBL)";
-#endif
-
-#include <sys/types.h>
-#include <sys/time.h>
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <memory.h>
-
-#include "pcap-int.h"
-
-#include "gencode.h"
-
-#include "gnuc.h"
-#ifdef HAVE_OS_PROTO_H
-#include "os-proto.h"
-#endif
-
-#ifdef BDEBUG
-extern int dflag;
-#endif
-
-#define A_ATOM BPF_MEMWORDS
-#define X_ATOM (BPF_MEMWORDS+1)
-
-#define NOP -1
-
-/*
- * This define is used to represent *both* the accumulator and
- * x register in use-def computations.
- * Currently, the use-def code assumes only one definition per instruction.
- */
-#define AX_ATOM N_ATOMS
-
-/*
- * A flag to indicate that further optimization is needed.
- * Iterative passes are continued until a given pass yields no
- * branch movement.
- */
-static int done;
-
-/*
- * A block is marked if only if its mark equals the current mark.
- * Rather than traverse the code array, marking each item, 'cur_mark' is
- * incremented.  This automatically makes each element unmarked.
- */
-static int cur_mark;
-#define isMarked(p) ((p)->mark == cur_mark)
-#define unMarkAll() cur_mark += 1
-#define Mark(p) ((p)->mark = cur_mark)
-
-static void opt_init(struct block *);
-static void opt_cleanup(void);
-
-static void make_marks(struct block *);
-static void mark_code(struct block *);
-
-static void intern_blocks(struct block *);
-
-static int eq_slist(struct slist *, struct slist *);
-
-static void find_levels_r(struct block *);
-
-static void find_levels(struct block *);
-static void find_dom(struct block *);
-static void propedom(struct edge *);
-static void find_edom(struct block *);
-static void find_closure(struct block *);
-static int atomuse(struct stmt *);
-static int atomdef(struct stmt *);
-static void compute_local_ud(struct block *);
-static void find_ud(struct block *);
-static void init_val(void);
-static int F(int, int, int);
-static inline void vstore(struct stmt *, int *, int, int);
-static void opt_blk(struct block *, int);
-static int use_conflict(struct block *, struct block *);
-static void opt_j(struct edge *);
-static void or_pullup(struct block *);
-static void and_pullup(struct block *);
-static void opt_blks(struct block *, int);
-static inline void link_inedge(struct edge *, struct block *);
-static void find_inedges(struct block *);
-static void opt_root(struct block **);
-static void opt_loop(struct block *, int);
-static void fold_op(struct stmt *, int, int);
-static inline struct slist *this_op(struct slist *);
-static void opt_not(struct block *);
-static void opt_peep(struct block *);
-static void opt_stmt(struct stmt *, int[], int);
-static void deadstmt(struct stmt *, struct stmt *[]);
-static void opt_deadstores(struct block *);
-static void opt_blk(struct block *, int);
-static int use_conflict(struct block *, struct block *);
-static void opt_j(struct edge *);
-static struct block *fold_edge(struct block *, struct edge *);
-static inline int eq_blk(struct block *, struct block *);
-static int slength(struct slist *);
-static int count_blocks(struct block *);
-static void number_blks_r(struct block *);
-static int count_stmts(struct block *);
-static int convert_code_r(struct block *);
-#ifdef BDEBUG
-static void opt_dump(struct block *);
-#endif
-
-static int n_blocks;
-struct block **blocks;
-static int n_edges;
-struct edge **edges;
-
-/*
- * A bit vector set representation of the dominators.
- * We round up the set size to the next power of two.
- */
-static int nodewords;
-static int edgewords;
-struct block **levels;
-bpf_u_int32 *space;
-#define BITS_PER_WORD (8*sizeof(bpf_u_int32))
-/*
- * True if a is in uset {p}
- */
-#define SET_MEMBER(p, a) \
-((p)[(unsigned)(a) / BITS_PER_WORD] & (1 << ((unsigned)(a) % BITS_PER_WORD)))
-
-/*
- * Add 'a' to uset p.
- */
-#define SET_INSERT(p, a) \
-(p)[(unsigned)(a) / BITS_PER_WORD] |= (1 << ((unsigned)(a) % BITS_PER_WORD))
-
-/*
- * Delete 'a' from uset p.
- */
-#define SET_DELETE(p, a) \
-(p)[(unsigned)(a) / BITS_PER_WORD] &= ~(1 << ((unsigned)(a) % BITS_PER_WORD))
-
-/*
- * a := a intersect b
- */
-#define SET_INTERSECT(a, b, n)\
-{\
-	register bpf_u_int32 *_x = a, *_y = b;\
-	register int _n = n;\
-	while (--_n >= 0) *_x++ &= *_y++;\
-}
-
-/*
- * a := a - b
- */
-#define SET_SUBTRACT(a, b, n)\
-{\
-	register bpf_u_int32 *_x = a, *_y = b;\
-	register int _n = n;\
-	while (--_n >= 0) *_x++ &=~ *_y++;\
-}
-
-/*
- * a := a union b
- */
-#define SET_UNION(a, b, n)\
-{\
-	register bpf_u_int32 *_x = a, *_y = b;\
-	register int _n = n;\
-	while (--_n >= 0) *_x++ |= *_y++;\
-}
-
-static uset all_dom_sets;
-static uset all_closure_sets;
-static uset all_edge_sets;
-
-#ifndef MAX
-#define MAX(a,b) ((a)>(b)?(a):(b))
-#endif
-
-static void
-find_levels_r(b)
-	struct block *b;
-{
-	int level;
-
-	if (isMarked(b))
-		return;
-
-	Mark(b);
-	b->link = 0;
-
-	if (JT(b)) {
-		find_levels_r(JT(b));
-		find_levels_r(JF(b));
-		level = MAX(JT(b)->level, JF(b)->level) + 1;
-	} else
-		level = 0;
-	b->level = level;
-	b->link = levels[level];
-	levels[level] = b;
-}
-
-/*
- * Level graph.  The levels go from 0 at the leaves to
- * N_LEVELS at the root.  The levels[] array points to the
- * first node of the level list, whose elements are linked
- * with the 'link' field of the struct block.
- */
-static void
-find_levels(root)
-	struct block *root;
-{
-	memset((char *)levels, 0, n_blocks * sizeof(*levels));
-	unMarkAll();
-	find_levels_r(root);
-}
-
-/*
- * Find dominator relationships.
- * Assumes graph has been leveled.
- */
-static void
-find_dom(root)
-	struct block *root;
-{
-	int i;
-	struct block *b;
-	bpf_u_int32 *x;
-
-	/*
-	 * Initialize sets to contain all nodes.
-	 */
-	x = all_dom_sets;
-	i = n_blocks * nodewords;
-	while (--i >= 0)
-		*x++ = ~0;
-	/* Root starts off empty. */
-	for (i = nodewords; --i >= 0;)
-		root->dom[i] = 0;
-
-	/* root->level is the highest level no found. */
-	for (i = root->level; i >= 0; --i) {
-		for (b = levels[i]; b; b = b->link) {
-			SET_INSERT(b->dom, b->id);
-			if (JT(b) == 0)
-				continue;
-			SET_INTERSECT(JT(b)->dom, b->dom, nodewords);
-			SET_INTERSECT(JF(b)->dom, b->dom, nodewords);
-		}
-	}
-}
-
-static void
-propedom(ep)
-	struct edge *ep;
-{
-	SET_INSERT(ep->edom, ep->id);
-	if (ep->succ) {
-		SET_INTERSECT(ep->succ->et.edom, ep->edom, edgewords);
-		SET_INTERSECT(ep->succ->ef.edom, ep->edom, edgewords);
-	}
-}
-
-/*
- * Compute edge dominators.
- * Assumes graph has been leveled and predecessors established.
- */
-static void
-find_edom(root)
-	struct block *root;
-{
-	int i;
-	uset x;
-	struct block *b;
-
-	x = all_edge_sets;
-	for (i = n_edges * edgewords; --i >= 0; )
-		x[i] = ~0;
-
-	/* root->level is the highest level no found. */
-	memset(root->et.edom, 0, edgewords * sizeof(*(uset)0));
-	memset(root->ef.edom, 0, edgewords * sizeof(*(uset)0));
-	for (i = root->level; i >= 0; --i) {
-		for (b = levels[i]; b != 0; b = b->link) {
-			propedom(&b->et);
-			propedom(&b->ef);
-		}
-	}
-}
-
-/*
- * Find the backwards transitive closure of the flow graph.  These sets
- * are backwards in the sense that we find the set of nodes that reach
- * a given node, not the set of nodes that can be reached by a node.
- *
- * Assumes graph has been leveled.
- */
-static void
-find_closure(root)
-	struct block *root;
-{
-	int i;
-	struct block *b;
-
-	/*
-	 * Initialize sets to contain no nodes.
-	 */
-	memset((char *)all_closure_sets, 0,
-	      n_blocks * nodewords * sizeof(*all_closure_sets));
-
-	/* root->level is the highest level no found. */
-	for (i = root->level; i >= 0; --i) {
-		for (b = levels[i]; b; b = b->link) {
-			SET_INSERT(b->closure, b->id);
-			if (JT(b) == 0)
-				continue;
-			SET_UNION(JT(b)->closure, b->closure, nodewords);
-			SET_UNION(JF(b)->closure, b->closure, nodewords);
-		}
-	}
-}
-
-/*
- * Return the register number that is used by s.  If A and X are both
- * used, return AX_ATOM.  If no register is used, return -1.
- *
- * The implementation should probably change to an array access.
- */
-static int
-atomuse(s)
-	struct stmt *s;
-{
-	register int c = s->code;
-
-	if (c == NOP)
-		return -1;
-
-	switch (BPF_CLASS(c)) {
-
-	case BPF_RET:
-		return (BPF_RVAL(c) == BPF_A) ? A_ATOM :
-			(BPF_RVAL(c) == BPF_X) ? X_ATOM : -1;
-
-	case BPF_LD:
-	case BPF_LDX:
-		return (BPF_MODE(c) == BPF_IND) ? X_ATOM :
-			(BPF_MODE(c) == BPF_MEM) ? s->k : -1;
-
-	case BPF_ST:
-		return A_ATOM;
-
-	case BPF_STX:
-		return X_ATOM;
-
-	case BPF_JMP:
-	case BPF_ALU:
-		if (BPF_SRC(c) == BPF_X)
-			return AX_ATOM;
-		return A_ATOM;
-
-	case BPF_MISC:
-		return BPF_MISCOP(c) == BPF_TXA ? X_ATOM : A_ATOM;
-	}
-	abort();
-	/* NOTREACHED */
-}
-
-/*
- * Return the register number that is defined by 's'.  We assume that
- * a single stmt cannot define more than one register.  If no register
- * is defined, return -1.
- *
- * The implementation should probably change to an array access.
- */
-static int
-atomdef(s)
-	struct stmt *s;
-{
-	if (s->code == NOP)
-		return -1;
-
-	switch (BPF_CLASS(s->code)) {
-
-	case BPF_LD:
-	case BPF_ALU:
-		return A_ATOM;
-
-	case BPF_LDX:
-		return X_ATOM;
-
-	case BPF_ST:
-	case BPF_STX:
-		return s->k;
-
-	case BPF_MISC:
-		return BPF_MISCOP(s->code) == BPF_TAX ? X_ATOM : A_ATOM;
-	}
-	return -1;
-}
-
-static void
-compute_local_ud(b)
-	struct block *b;
-{
-	struct slist *s;
-	atomset def = 0, use = 0, kill = 0;
-	int atom;
-
-	for (s = b->stmts; s; s = s->next) {
-		if (s->s.code == NOP)
-			continue;
-		atom = atomuse(&s->s);
-		if (atom >= 0) {
-			if (atom == AX_ATOM) {
-				if (!ATOMELEM(def, X_ATOM))
-					use |= ATOMMASK(X_ATOM);
-				if (!ATOMELEM(def, A_ATOM))
-					use |= ATOMMASK(A_ATOM);
-			}
-			else if (atom < N_ATOMS) {
-				if (!ATOMELEM(def, atom))
-					use |= ATOMMASK(atom);
-			}
-			else
-				abort();
-		}
-		atom = atomdef(&s->s);
-		if (atom >= 0) {
-			if (!ATOMELEM(use, atom))
-				kill |= ATOMMASK(atom);
-			def |= ATOMMASK(atom);
-		}
-	}
-	if (!ATOMELEM(def, A_ATOM) && BPF_CLASS(b->s.code) == BPF_JMP)
-		use |= ATOMMASK(A_ATOM);
-
-	b->def = def;
-	b->kill = kill;
-	b->in_use = use;
-}
-
-/*
- * Assume graph is already leveled.
- */
-static void
-find_ud(root)
-	struct block *root;
-{
-	int i, maxlevel;
-	struct block *p;
-
-	/*
-	 * root->level is the highest level no found;
-	 * count down from there.
-	 */
-	maxlevel = root->level;
-	for (i = maxlevel; i >= 0; --i)
-		for (p = levels[i]; p; p = p->link) {
-			compute_local_ud(p);
-			p->out_use = 0;
-		}
-
-	for (i = 1; i <= maxlevel; ++i) {
-		for (p = levels[i]; p; p = p->link) {
-			p->out_use |= JT(p)->in_use | JF(p)->in_use;
-			p->in_use |= p->out_use &~ p->kill;
-		}
-	}
-}
-
-/*
- * These data structures are used in a Cocke and Shwarz style
- * value numbering scheme.  Since the flowgraph is acyclic,
- * exit values can be propagated from a node's predecessors
- * provided it is uniquely defined.
- */
-struct valnode {
-	int code;
-	int v0, v1;
-	int val;
-	struct valnode *next;
-};
-
-#define MODULUS 213
-static struct valnode *hashtbl[MODULUS];
-static int curval;
-static int maxval;
-
-/* Integer constants mapped with the load immediate opcode. */
-#define K(i) F(BPF_LD|BPF_IMM|BPF_W, i, 0L)
-
-struct vmapinfo {
-	int is_const;
-	bpf_int32 const_val;
-};
-
-struct vmapinfo *vmap;
-struct valnode *vnode_base;
-struct valnode *next_vnode;
-
-static void
-init_val()
-{
-	curval = 0;
-	next_vnode = vnode_base;
-	memset((char *)vmap, 0, maxval * sizeof(*vmap));
-	memset((char *)hashtbl, 0, sizeof hashtbl);
-}
-
-/* Because we really don't have an IR, this stuff is a little messy. */
-static int
-F(code, v0, v1)
-	int code;
-	int v0, v1;
-{
-	u_int hash;
-	int val;
-	struct valnode *p;
-
-	hash = (u_int)code ^ (v0 << 4) ^ (v1 << 8);
-	hash %= MODULUS;
-
-	for (p = hashtbl[hash]; p; p = p->next)
-		if (p->code == code && p->v0 == v0 && p->v1 == v1)
-			return p->val;
-
-	val = ++curval;
-	if (BPF_MODE(code) == BPF_IMM &&
-	    (BPF_CLASS(code) == BPF_LD || BPF_CLASS(code) == BPF_LDX)) {
-		vmap[val].const_val = v0;
-		vmap[val].is_const = 1;
-	}
-	p = next_vnode++;
-	p->val = val;
-	p->code = code;
-	p->v0 = v0;
-	p->v1 = v1;
-	p->next = hashtbl[hash];
-	hashtbl[hash] = p;
-
-	return val;
-}
-
-static inline void
-vstore(s, valp, newval, alter)
-	struct stmt *s;
-	int *valp;
-	int newval;
-	int alter;
-{
-	if (alter && *valp == newval)
-		s->code = NOP;
-	else
-		*valp = newval;
-}
-
-static void
-fold_op(s, v0, v1)
-	struct stmt *s;
-	int v0, v1;
-{
-	bpf_int32 a, b;
-
-	a = vmap[v0].const_val;
-	b = vmap[v1].const_val;
-
-	switch (BPF_OP(s->code)) {
-	case BPF_ADD:
-		a += b;
-		break;
-
-	case BPF_SUB:
-		a -= b;
-		break;
-
-	case BPF_MUL:
-		a *= b;
-		break;
-
-	case BPF_DIV:
-		if (b == 0)
-			bpf_error("division by zero");
-		a /= b;
-		break;
-
-	case BPF_AND:
-		a &= b;
-		break;
-
-	case BPF_OR:
-		a |= b;
-		break;
-
-	case BPF_LSH:
-		a <<= b;
-		break;
-
-	case BPF_RSH:
-		a >>= b;
-		break;
-
-	case BPF_NEG:
-		a = -a;
-		break;
-
-	default:
-		abort();
-	}
-	s->k = a;
-	s->code = BPF_LD|BPF_IMM;
-	done = 0;
-}
-
-static inline struct slist *
-this_op(s)
-	struct slist *s;
-{
-	while (s != 0 && s->s.code == NOP)
-		s = s->next;
-	return s;
-}
-
-static void
-opt_not(b)
-	struct block *b;
-{
-	struct block *tmp = JT(b);
-
-	JT(b) = JF(b);
-	JF(b) = tmp;
-}
-
-static void
-opt_peep(b)
-	struct block *b;
-{
-	struct slist *s;
-	struct slist *next, *last;
-	int val;
-
-	s = b->stmts;
-	if (s == 0)
-		return;
-
-	last = s;
-	while (1) {
-		s = this_op(s);
-		if (s == 0)
-			break;
-		next = this_op(s->next);
-		if (next == 0)
-			break;
-		last = next;
-
-		/*
-		 * st  M[k]	-->	st  M[k]
-		 * ldx M[k]		tax
-		 */
-		if (s->s.code == BPF_ST &&
-		    next->s.code == (BPF_LDX|BPF_MEM) &&
-		    s->s.k == next->s.k) {
-			done = 0;
-			next->s.code = BPF_MISC|BPF_TAX;
-		}
-		/*
-		 * ld  #k	-->	ldx  #k
-		 * tax			txa
-		 */
-		if (s->s.code == (BPF_LD|BPF_IMM) &&
-		    next->s.code == (BPF_MISC|BPF_TAX)) {
-			s->s.code = BPF_LDX|BPF_IMM;
-			next->s.code = BPF_MISC|BPF_TXA;
-			done = 0;
-		}
-		/*
-		 * This is an ugly special case, but it happens
-		 * when you say tcp[k] or udp[k] where k is a constant.
-		 */
-		if (s->s.code == (BPF_LD|BPF_IMM)) {
-			struct slist *add, *tax, *ild;
-
-			/*
-			 * Check that X isn't used on exit from this
-			 * block (which the optimizer might cause).
-			 * We know the code generator won't generate
-			 * any local dependencies.
-			 */
-			if (ATOMELEM(b->out_use, X_ATOM))
-				break;
-
-			if (next->s.code != (BPF_LDX|BPF_MSH|BPF_B))
-				add = next;
-			else
-				add = this_op(next->next);
-			if (add == 0 || add->s.code != (BPF_ALU|BPF_ADD|BPF_X))
-				break;
-
-			tax = this_op(add->next);
-			if (tax == 0 || tax->s.code != (BPF_MISC|BPF_TAX))
-				break;
-
-			ild = this_op(tax->next);
-			if (ild == 0 || BPF_CLASS(ild->s.code) != BPF_LD ||
-			    BPF_MODE(ild->s.code) != BPF_IND)
-				break;
-			/*
-			 * XXX We need to check that X is not
-			 * subsequently used.  We know we can eliminate the
-			 * accumulator modifications since it is defined
-			 * by the last stmt of this sequence.
-			 *
-			 * We want to turn this sequence:
-			 *
-			 * (004) ldi     #0x2		{s}
-			 * (005) ldxms   [14]		{next}  -- optional
-			 * (006) addx			{add}
-			 * (007) tax			{tax}
-			 * (008) ild     [x+0]		{ild}
-			 *
-			 * into this sequence:
-			 *
-			 * (004) nop
-			 * (005) ldxms   [14]
-			 * (006) nop
-			 * (007) nop
-			 * (008) ild     [x+2]
-			 *
-			 */
-			ild->s.k += s->s.k;
-			s->s.code = NOP;
-			add->s.code = NOP;
-			tax->s.code = NOP;
-			done = 0;
-		}
-		s = next;
-	}
-	/*
-	 * If we have a subtract to do a comparison, and the X register
-	 * is a known constant, we can merge this value into the
-	 * comparison.
-	 */
-	if (last->s.code == (BPF_ALU|BPF_SUB|BPF_X) &&
-	    !ATOMELEM(b->out_use, A_ATOM)) {
-		val = b->val[X_ATOM];
-		if (vmap[val].is_const) {
-			int op;
-
-			b->s.k += vmap[val].const_val;
-			op = BPF_OP(b->s.code);
-			if (op == BPF_JGT || op == BPF_JGE) {
-				struct block *t = JT(b);
-				JT(b) = JF(b);
-				JF(b) = t;
-				b->s.k += 0x80000000;
-			}
-			last->s.code = NOP;
-			done = 0;
-		} else if (b->s.k == 0) {
-			/*
-			 * sub x  ->	nop
-			 * j  #0	j  x
-			 */
-			last->s.code = NOP;
-			b->s.code = BPF_CLASS(b->s.code) | BPF_OP(b->s.code) |
-				BPF_X;
-			done = 0;
-		}
-	}
-	/*
-	 * Likewise, a constant subtract can be simplified.
-	 */
-	else if (last->s.code == (BPF_ALU|BPF_SUB|BPF_K) &&
-		 !ATOMELEM(b->out_use, A_ATOM)) {
-		int op;
-
-		b->s.k += last->s.k;
-		last->s.code = NOP;
-		op = BPF_OP(b->s.code);
-		if (op == BPF_JGT || op == BPF_JGE) {
-			struct block *t = JT(b);
-			JT(b) = JF(b);
-			JF(b) = t;
-			b->s.k += 0x80000000;
-		}
-		done = 0;
-	}
-	/*
-	 * and #k	nop
-	 * jeq #0  ->	jset #k
-	 */
-	if (last->s.code == (BPF_ALU|BPF_AND|BPF_K) &&
-	    !ATOMELEM(b->out_use, A_ATOM) && b->s.k == 0) {
-		b->s.k = last->s.k;
-		b->s.code = BPF_JMP|BPF_K|BPF_JSET;
-		last->s.code = NOP;
-		done = 0;
-		opt_not(b);
-	}
-	/*
-	 * If the accumulator is a known constant, we can compute the
-	 * comparison result.
-	 */
-	val = b->val[A_ATOM];
-	if (vmap[val].is_const && BPF_SRC(b->s.code) == BPF_K) {
-		bpf_int32 v = vmap[val].const_val;
-		switch (BPF_OP(b->s.code)) {
-
-		case BPF_JEQ:
-			v = v == b->s.k;
-			break;
-
-		case BPF_JGT:
-			v = (unsigned)v > b->s.k;
-			break;
-
-		case BPF_JGE:
-			v = (unsigned)v >= b->s.k;
-			break;
-
-		case BPF_JSET:
-			v &= b->s.k;
-			break;
-
-		default:
-			abort();
-		}
-		if (JF(b) != JT(b))
-			done = 0;
-		if (v)
-			JF(b) = JT(b);
-		else
-			JT(b) = JF(b);
-	}
-}
-
-/*
- * Compute the symbolic value of expression of 's', and update
- * anything it defines in the value table 'val'.  If 'alter' is true,
- * do various optimizations.  This code would be cleaner if symbolic
- * evaluation and code transformations weren't folded together.
- */
-static void
-opt_stmt(s, val, alter)
-	struct stmt *s;
-	int val[];
-	int alter;
-{
-	int op;
-	int v;
-
-	switch (s->code) {
-
-	case BPF_LD|BPF_ABS|BPF_W:
-	case BPF_LD|BPF_ABS|BPF_H:
-	case BPF_LD|BPF_ABS|BPF_B:
-		v = F(s->code, s->k, 0L);
-		vstore(s, &val[A_ATOM], v, alter);
-		break;
-
-	case BPF_LD|BPF_IND|BPF_W:
-	case BPF_LD|BPF_IND|BPF_H:
-	case BPF_LD|BPF_IND|BPF_B:
-		v = val[X_ATOM];
-		if (alter && vmap[v].is_const) {
-			s->code = BPF_LD|BPF_ABS|BPF_SIZE(s->code);
-			s->k += vmap[v].const_val;
-			v = F(s->code, s->k, 0L);
-			done = 0;
-		}
-		else
-			v = F(s->code, s->k, v);
-		vstore(s, &val[A_ATOM], v, alter);
-		break;
-
-	case BPF_LD|BPF_LEN:
-		v = F(s->code, 0L, 0L);
-		vstore(s, &val[A_ATOM], v, alter);
-		break;
-
-	case BPF_LD|BPF_IMM:
-		v = K(s->k);
-		vstore(s, &val[A_ATOM], v, alter);
-		break;
-
-	case BPF_LDX|BPF_IMM:
-		v = K(s->k);
-		vstore(s, &val[X_ATOM], v, alter);
-		break;
-
-	case BPF_LDX|BPF_MSH|BPF_B:
-		v = F(s->code, s->k, 0L);
-		vstore(s, &val[X_ATOM], v, alter);
-		break;
-
-	case BPF_ALU|BPF_NEG:
-		if (alter && vmap[val[A_ATOM]].is_const) {
-			s->code = BPF_LD|BPF_IMM;
-			s->k = -vmap[val[A_ATOM]].const_val;
-			val[A_ATOM] = K(s->k);
-		}
-		else
-			val[A_ATOM] = F(s->code, val[A_ATOM], 0L);
-		break;
-
-	case BPF_ALU|BPF_ADD|BPF_K:
-	case BPF_ALU|BPF_SUB|BPF_K:
-	case BPF_ALU|BPF_MUL|BPF_K:
-	case BPF_ALU|BPF_DIV|BPF_K:
-	case BPF_ALU|BPF_AND|BPF_K:
-	case BPF_ALU|BPF_OR|BPF_K:
-	case BPF_ALU|BPF_LSH|BPF_K:
-	case BPF_ALU|BPF_RSH|BPF_K:
-		op = BPF_OP(s->code);
-		if (alter) {
-			if (s->k == 0) {
-				if (op == BPF_ADD || op == BPF_SUB ||
-				    op == BPF_LSH || op == BPF_RSH ||
-				    op == BPF_OR) {
-					s->code = NOP;
-					break;
-				}
-				if (op == BPF_MUL || op == BPF_AND) {
-					s->code = BPF_LD|BPF_IMM;
-					val[A_ATOM] = K(s->k);
-					break;
-				}
-			}
-			if (vmap[val[A_ATOM]].is_const) {
-				fold_op(s, val[A_ATOM], K(s->k));
-				val[A_ATOM] = K(s->k);
-				break;
-			}
-		}
-		val[A_ATOM] = F(s->code, val[A_ATOM], K(s->k));
-		break;
-
-	case BPF_ALU|BPF_ADD|BPF_X:
-	case BPF_ALU|BPF_SUB|BPF_X:
-	case BPF_ALU|BPF_MUL|BPF_X:
-	case BPF_ALU|BPF_DIV|BPF_X:
-	case BPF_ALU|BPF_AND|BPF_X:
-	case BPF_ALU|BPF_OR|BPF_X:
-	case BPF_ALU|BPF_LSH|BPF_X:
-	case BPF_ALU|BPF_RSH|BPF_X:
-		op = BPF_OP(s->code);
-		if (alter && vmap[val[X_ATOM]].is_const) {
-			if (vmap[val[A_ATOM]].is_const) {
-				fold_op(s, val[A_ATOM], val[X_ATOM]);
-				val[A_ATOM] = K(s->k);
-			}
-			else {
-				s->code = BPF_ALU|BPF_K|op;
-				s->k = vmap[val[X_ATOM]].const_val;
-				done = 0;
-				val[A_ATOM] =
-					F(s->code, val[A_ATOM], K(s->k));
-			}
-			break;
-		}
-		/*
-		 * Check if we're doing something to an accumulator
-		 * that is 0, and simplify.  This may not seem like
-		 * much of a simplification but it could open up further
-		 * optimizations.
-		 * XXX We could also check for mul by 1, and -1, etc.
-		 */
-		if (alter && vmap[val[A_ATOM]].is_const
-		    && vmap[val[A_ATOM]].const_val == 0) {
-			if (op == BPF_ADD || op == BPF_OR ||
-			    op == BPF_LSH || op == BPF_RSH || op == BPF_SUB) {
-				s->code = BPF_MISC|BPF_TXA;
-				vstore(s, &val[A_ATOM], val[X_ATOM], alter);
-				break;
-			}
-			else if (op == BPF_MUL || op == BPF_DIV ||
-				 op == BPF_AND) {
-				s->code = BPF_LD|BPF_IMM;
-				s->k = 0;
-				vstore(s, &val[A_ATOM], K(s->k), alter);
-				break;
-			}
-			else if (op == BPF_NEG) {
-				s->code = NOP;
-				break;
-			}
-		}
-		val[A_ATOM] = F(s->code, val[A_ATOM], val[X_ATOM]);
-		break;
-
-	case BPF_MISC|BPF_TXA:
-		vstore(s, &val[A_ATOM], val[X_ATOM], alter);
-		break;
-
-	case BPF_LD|BPF_MEM:
-		v = val[s->k];
-		if (alter && vmap[v].is_const) {
-			s->code = BPF_LD|BPF_IMM;
-			s->k = vmap[v].const_val;
-			done = 0;
-		}
-		vstore(s, &val[A_ATOM], v, alter);
-		break;
-
-	case BPF_MISC|BPF_TAX:
-		vstore(s, &val[X_ATOM], val[A_ATOM], alter);
-		break;
-
-	case BPF_LDX|BPF_MEM:
-		v = val[s->k];
-		if (alter && vmap[v].is_const) {
-			s->code = BPF_LDX|BPF_IMM;
-			s->k = vmap[v].const_val;
-			done = 0;
-		}
-		vstore(s, &val[X_ATOM], v, alter);
-		break;
-
-	case BPF_ST:
-		vstore(s, &val[s->k], val[A_ATOM], alter);
-		break;
-
-	case BPF_STX:
-		vstore(s, &val[s->k], val[X_ATOM], alter);
-		break;
-	}
-}
-
-static void
-deadstmt(s, last)
-	register struct stmt *s;
-	register struct stmt *last[];
-{
-	register int atom;
-
-	atom = atomuse(s);
-	if (atom >= 0) {
-		if (atom == AX_ATOM) {
-			last[X_ATOM] = 0;
-			last[A_ATOM] = 0;
-		}
-		else
-			last[atom] = 0;
-	}
-	atom = atomdef(s);
-	if (atom >= 0) {
-		if (last[atom]) {
-			done = 0;
-			last[atom]->code = NOP;
-		}
-		last[atom] = s;
-	}
-}
-
-static void
-opt_deadstores(b)
-	register struct block *b;
-{
-	register struct slist *s;
-	register int atom;
-	struct stmt *last[N_ATOMS];
-
-	memset((char *)last, 0, sizeof last);
-
-	for (s = b->stmts; s != 0; s = s->next)
-		deadstmt(&s->s, last);
-	deadstmt(&b->s, last);
-
-	for (atom = 0; atom < N_ATOMS; ++atom)
-		if (last[atom] && !ATOMELEM(b->out_use, atom)) {
-			last[atom]->code = NOP;
-			done = 0;
-		}
-}
-
-static void
-opt_blk(b, do_stmts)
-	struct block *b;
-	int do_stmts;
-{
-	struct slist *s;
-	struct edge *p;
-	int i;
-	bpf_int32 aval;
-
-#if 0
-	for (s = b->stmts; s && s->next; s = s->next)
-		if (BPF_CLASS(s->s.code) == BPF_JMP) {
-			do_stmts = 0;
-			break;
-		}
-#endif
-
-	/*
-	 * Initialize the atom values.
-	 * If we have no predecessors, everything is undefined.
-	 * Otherwise, we inherent our values from our predecessors.
-	 * If any register has an ambiguous value (i.e. control paths are
-	 * merging) give it the undefined value of 0.
-	 */
-	p = b->in_edges;
-	if (p == 0)
-		memset((char *)b->val, 0, sizeof(b->val));
-	else {
-		memcpy((char *)b->val, (char *)p->pred->val, sizeof(b->val));
-		while ((p = p->next) != NULL) {
-			for (i = 0; i < N_ATOMS; ++i)
-				if (b->val[i] != p->pred->val[i])
-					b->val[i] = 0;
-		}
-	}
-	aval = b->val[A_ATOM];
-	for (s = b->stmts; s; s = s->next)
-		opt_stmt(&s->s, b->val, do_stmts);
-
-	/*
-	 * This is a special case: if we don't use anything from this
-	 * block, and we load the accumulator with value that is
-	 * already there, or if this block is a return,
-	 * eliminate all the statements.
-	 */
-	if (do_stmts && 
-	    ((b->out_use == 0 && aval != 0 &&b->val[A_ATOM] == aval) ||
-	     BPF_CLASS(b->s.code) == BPF_RET)) {
-		if (b->stmts != 0) {
-			b->stmts = 0;
-			done = 0;
-		}
-	} else {
-		opt_peep(b);
-		opt_deadstores(b);
-	}
-	/*
-	 * Set up values for branch optimizer.
-	 */
-	if (BPF_SRC(b->s.code) == BPF_K)
-		b->oval = K(b->s.k);
-	else
-		b->oval = b->val[X_ATOM];
-	b->et.code = b->s.code;
-	b->ef.code = -b->s.code;
-}
-
-/*
- * Return true if any register that is used on exit from 'succ', has
- * an exit value that is different from the corresponding exit value
- * from 'b'.
- */
-static int
-use_conflict(b, succ)
-	struct block *b, *succ;
-{
-	int atom;
-	atomset use = succ->out_use;
-
-	if (use == 0)
-		return 0;
-
-	for (atom = 0; atom < N_ATOMS; ++atom)
-		if (ATOMELEM(use, atom))
-			if (b->val[atom] != succ->val[atom])
-				return 1;
-	return 0;
-}
-
-static struct block *
-fold_edge(child, ep)
-	struct block *child;
-	struct edge *ep;
-{
-	int sense;
-	int aval0, aval1, oval0, oval1;
-	int code = ep->code;
-
-	if (code < 0) {
-		code = -code;
-		sense = 0;
-	} else
-		sense = 1;
-
-	if (child->s.code != code)
-		return 0;
-
-	aval0 = child->val[A_ATOM];
-	oval0 = child->oval;
-	aval1 = ep->pred->val[A_ATOM];
-	oval1 = ep->pred->oval;
-
-	if (aval0 != aval1)
-		return 0;
-
-	if (oval0 == oval1)
-		/*
-		 * The operands are identical, so the
-		 * result is true if a true branch was
-		 * taken to get here, otherwise false.
-		 */
-		return sense ? JT(child) : JF(child);
-
-	if (sense && code == (BPF_JMP|BPF_JEQ|BPF_K))
-		/*
-		 * At this point, we only know the comparison if we
-		 * came down the true branch, and it was an equality
-		 * comparison with a constant.  We rely on the fact that
-		 * distinct constants have distinct value numbers.
-		 */
-		return JF(child);
-
-	return 0;
-}
-
-static void
-opt_j(ep)
-	struct edge *ep;
-{
-	register int i, k;
-	register struct block *target;
-
-	if (JT(ep->succ) == 0)
-		return;
-
-	if (JT(ep->succ) == JF(ep->succ)) {
-		/*
-		 * Common branch targets can be eliminated, provided
-		 * there is no data dependency.
-		 */
-		if (!use_conflict(ep->pred, ep->succ->et.succ)) {
-			done = 0;
-			ep->succ = JT(ep->succ);
-		}
-	}
-	/*
-	 * For each edge dominator that matches the successor of this
-	 * edge, promote the edge successor to the its grandchild.
-	 *
-	 * XXX We violate the set abstraction here in favor a reasonably
-	 * efficient loop.
-	 */
- top:
-	for (i = 0; i < edgewords; ++i) {
-		register bpf_u_int32 x = ep->edom[i];
-
-		while (x != 0) {
-			k = ffs(x) - 1;
-			x &=~ (1 << k);
-			k += i * BITS_PER_WORD;
-
-			target = fold_edge(ep->succ, edges[k]);
-			/*
-			 * Check that there is no data dependency between
-			 * nodes that will be violated if we move the edge.
-			 */
-			if (target != 0 && !use_conflict(ep->pred, target)) {
-				done = 0;
-				ep->succ = target;
-				if (JT(target) != 0)
-					/*
-					 * Start over unless we hit a leaf.
-					 */
-					goto top;
-				return;
-			}
-		}
-	}
-}
-
-
-static void
-or_pullup(b)
-	struct block *b;
-{
-	int val, at_top;
-	struct block *pull;
-	struct block **diffp, **samep;
-	struct edge *ep;
-
-	ep = b->in_edges;
-	if (ep == 0)
-		return;
-
-	/*
-	 * Make sure each predecessor loads the same value.
-	 * XXX why?
-	 */
-	val = ep->pred->val[A_ATOM];
-	for (ep = ep->next; ep != 0; ep = ep->next)
-		if (val != ep->pred->val[A_ATOM])
-			return;
-
-	if (JT(b->in_edges->pred) == b)
-		diffp = &JT(b->in_edges->pred);
-	else
-		diffp = &JF(b->in_edges->pred);
-
-	at_top = 1;
-	while (1) {
-		if (*diffp == 0)
-			return;
-
-		if (JT(*diffp) != JT(b))
-			return;
-
-		if (!SET_MEMBER((*diffp)->dom, b->id))
-			return;
-
-		if ((*diffp)->val[A_ATOM] != val)
-			break;
-
-		diffp = &JF(*diffp);
-		at_top = 0;
-	}
-	samep = &JF(*diffp);
-	while (1) {
-		if (*samep == 0)
-			return;
-
-		if (JT(*samep) != JT(b))
-			return;
-
-		if (!SET_MEMBER((*samep)->dom, b->id))
-			return;
-
-		if ((*samep)->val[A_ATOM] == val)
-			break;
-
-		/* XXX Need to check that there are no data dependencies
-		   between dp0 and dp1.  Currently, the code generator
-		   will not produce such dependencies. */
-		samep = &JF(*samep);
-	}
-#ifdef notdef
-	/* XXX This doesn't cover everything. */
-	for (i = 0; i < N_ATOMS; ++i)
-		if ((*samep)->val[i] != pred->val[i])
-			return;
-#endif
-	/* Pull up the node. */
-	pull = *samep;
-	*samep = JF(pull);
-	JF(pull) = *diffp;
-
-	/*
-	 * At the top of the chain, each predecessor needs to point at the
-	 * pulled up node.  Inside the chain, there is only one predecessor
-	 * to worry about.
-	 */
-	if (at_top) {
-		for (ep = b->in_edges; ep != 0; ep = ep->next) {
-			if (JT(ep->pred) == b)
-				JT(ep->pred) = pull;
-			else
-				JF(ep->pred) = pull;
-		}
-	}
-	else
-		*diffp = pull;
-
-	done = 0;
-}
-
-static void
-and_pullup(b)
-	struct block *b;
-{
-	int val, at_top;
-	struct block *pull;
-	struct block **diffp, **samep;
-	struct edge *ep;
-
-	ep = b->in_edges;
-	if (ep == 0)
-		return;
-
-	/*
-	 * Make sure each predecessor loads the same value.
-	 */
-	val = ep->pred->val[A_ATOM];
-	for (ep = ep->next; ep != 0; ep = ep->next)
-		if (val != ep->pred->val[A_ATOM])
-			return;
-
-	if (JT(b->in_edges->pred) == b)
-		diffp = &JT(b->in_edges->pred);
-	else
-		diffp = &JF(b->in_edges->pred);
-
-	at_top = 1;
-	while (1) {
-		if (*diffp == 0)
-			return;
-
-		if (JF(*diffp) != JF(b))
-			return;
-
-		if (!SET_MEMBER((*diffp)->dom, b->id))
-			return;
-
-		if ((*diffp)->val[A_ATOM] != val)
-			break;
-
-		diffp = &JT(*diffp);
-		at_top = 0;
-	}
-	samep = &JT(*diffp);
-	while (1) {
-		if (*samep == 0)
-			return;
-
-		if (JF(*samep) != JF(b))
-			return;
-
-		if (!SET_MEMBER((*samep)->dom, b->id))
-			return;
-
-		if ((*samep)->val[A_ATOM] == val)
-			break;
-
-		/* XXX Need to check that there are no data dependencies
-		   between diffp and samep.  Currently, the code generator
-		   will not produce such dependencies. */
-		samep = &JT(*samep);
-	}
-#ifdef notdef
-	/* XXX This doesn't cover everything. */
-	for (i = 0; i < N_ATOMS; ++i)
-		if ((*samep)->val[i] != pred->val[i])
-			return;
-#endif
-	/* Pull up the node. */
-	pull = *samep;
-	*samep = JT(pull);
-	JT(pull) = *diffp;
-
-	/*
-	 * At the top of the chain, each predecessor needs to point at the
-	 * pulled up node.  Inside the chain, there is only one predecessor
-	 * to worry about.
-	 */
-	if (at_top) {
-		for (ep = b->in_edges; ep != 0; ep = ep->next) {
-			if (JT(ep->pred) == b)
-				JT(ep->pred) = pull;
-			else
-				JF(ep->pred) = pull;
-		}
-	}
-	else
-		*diffp = pull;
-
-	done = 0;
-}
-
-static void
-opt_blks(root, do_stmts)
-	struct block *root;
-	int do_stmts;
-{
-	int i, maxlevel;
-	struct block *p;
-
-	init_val();
-	maxlevel = root->level;
-	for (i = maxlevel; i >= 0; --i)
-		for (p = levels[i]; p; p = p->link)
-			opt_blk(p, do_stmts);
-
-	if (do_stmts)
-		/*
-		 * No point trying to move branches; it can't possibly
-		 * make a difference at this point.
-		 */
-		return;
-
-	for (i = 1; i <= maxlevel; ++i) {
-		for (p = levels[i]; p; p = p->link) {
-			opt_j(&p->et);
-			opt_j(&p->ef);
-		}
-	}
-	for (i = 1; i <= maxlevel; ++i) {
-		for (p = levels[i]; p; p = p->link) {
-			or_pullup(p);
-			and_pullup(p);
-		}
-	}
-}
-
-static inline void
-link_inedge(parent, child)
-	struct edge *parent;
-	struct block *child;
-{
-	parent->next = child->in_edges;
-	child->in_edges = parent;
-}
-
-static void
-find_inedges(root)
-	struct block *root;
-{
-	int i;
-	struct block *b;
-
-	for (i = 0; i < n_blocks; ++i)
-		blocks[i]->in_edges = 0;
-
-	/*
-	 * Traverse the graph, adding each edge to the predecessor
-	 * list of its successors.  Skip the leaves (i.e. level 0).
-	 */
-	for (i = root->level; i > 0; --i) {
-		for (b = levels[i]; b != 0; b = b->link) {
-			link_inedge(&b->et, JT(b));
-			link_inedge(&b->ef, JF(b));
-		}
-	}
-}
-
-static void
-opt_root(b)
-	struct block **b;
-{
-	struct slist *tmp, *s;
-
-	s = (*b)->stmts;
-	(*b)->stmts = 0;
-	while (BPF_CLASS((*b)->s.code) == BPF_JMP && JT(*b) == JF(*b))
-		*b = JT(*b);
-
-	tmp = (*b)->stmts;
-	if (tmp != 0)
-		sappend(s, tmp);
-	(*b)->stmts = s;
-
-	/*
-	 * If the root node is a return, then there is no
-	 * point executing any statements (since the bpf machine
-	 * has no side effects).
-	 */
-	if (BPF_CLASS((*b)->s.code) == BPF_RET)
-		(*b)->stmts = 0;
-}
-
-static void
-opt_loop(root, do_stmts)
-	struct block *root;
-	int do_stmts;
-{
-
-#ifdef BDEBUG
-	if (dflag > 1)
-		opt_dump(root);
-#endif
-	do {
-		done = 1;
-		find_levels(root);
-		find_dom(root);
-		find_closure(root);
-		find_inedges(root);
-		find_ud(root);
-		find_edom(root);
-		opt_blks(root, do_stmts);
-#ifdef BDEBUG
-		if (dflag > 1)
-			opt_dump(root);
-#endif
-	} while (!done);
-}
-
-/*
- * Optimize the filter code in its dag representation.
- */
-void
-bpf_optimize(rootp)
-	struct block **rootp;
-{
-	struct block *root;
-
-	root = *rootp;
-
-	opt_init(root);
-	opt_loop(root, 0);
-	opt_loop(root, 1);
-	intern_blocks(root);
-	opt_root(rootp);
-	opt_cleanup();
-}
-
-static void
-make_marks(p)
-	struct block *p;
-{
-	if (!isMarked(p)) {
-		Mark(p);
-		if (BPF_CLASS(p->s.code) != BPF_RET) {
-			make_marks(JT(p));
-			make_marks(JF(p));
-		}
-	}
-}
-
-/*
- * Mark code array such that isMarked(i) is true
- * only for nodes that are alive.
- */
-static void
-mark_code(p)
-	struct block *p;
-{
-	cur_mark += 1;
-	make_marks(p);
-}
-
-/*
- * True iff the two stmt lists load the same value from the packet into
- * the accumulator.
- */
-static int
-eq_slist(x, y)
-	struct slist *x, *y;
-{
-	while (1) {
-		while (x && x->s.code == NOP)
-			x = x->next;
-		while (y && y->s.code == NOP)
-			y = y->next;
-		if (x == 0)
-			return y == 0;
-		if (y == 0)
-			return x == 0;
-		if (x->s.code != y->s.code || x->s.k != y->s.k)
-			return 0;
-		x = x->next;
-		y = y->next;
-	}
-}
-
-static inline int
-eq_blk(b0, b1)
-	struct block *b0, *b1;
-{
-	if (b0->s.code == b1->s.code &&
-	    b0->s.k == b1->s.k &&
-	    b0->et.succ == b1->et.succ &&
-	    b0->ef.succ == b1->ef.succ)
-		return eq_slist(b0->stmts, b1->stmts);
-	return 0;
-}
-
-static void
-intern_blocks(root)
-	struct block *root;
-{
-	struct block *p;
-	int i, j;
-	int done;
- top:
-	done = 1;
-	for (i = 0; i < n_blocks; ++i)
-		blocks[i]->link = 0;
-
-	mark_code(root);
-
-	for (i = n_blocks - 1; --i >= 0; ) {
-		if (!isMarked(blocks[i]))
-			continue;
-		for (j = i + 1; j < n_blocks; ++j) {
-			if (!isMarked(blocks[j]))
-				continue;
-			if (eq_blk(blocks[i], blocks[j])) {
-				blocks[i]->link = blocks[j]->link ?
-					blocks[j]->link : blocks[j];
-				break;
-			}
-		}
-	}
-	for (i = 0; i < n_blocks; ++i) {
-		p = blocks[i];
-		if (JT(p) == 0)
-			continue;
-		if (JT(p)->link) {
-			done = 0;
-			JT(p) = JT(p)->link;
-		}
-		if (JF(p)->link) {
-			done = 0;
-			JF(p) = JF(p)->link;
-		}
-	}
-	if (!done)
-		goto top;
-}
-
-static void
-opt_cleanup()
-{
-	free((void *)vnode_base);
-	free((void *)vmap);
-	free((void *)edges);
-	free((void *)space);
-	free((void *)levels);
-	free((void *)blocks);
-}
-
-/*
- * Return the number of stmts in 's'.
- */
-static int
-slength(s)
-	struct slist *s;
-{
-	int n = 0;
-
-	for (; s; s = s->next)
-		if (s->s.code != NOP)
-			++n;
-	return n;
-}
-
-/*
- * Return the number of nodes reachable by 'p'.
- * All nodes should be initially unmarked.
- */
-static int
-count_blocks(p)
-	struct block *p;
-{
-	if (p == 0 || isMarked(p))
-		return 0;
-	Mark(p);
-	return count_blocks(JT(p)) + count_blocks(JF(p)) + 1;
-}
-
-/*
- * Do a depth first search on the flow graph, numbering the
- * the basic blocks, and entering them into the 'blocks' array.`
- */
-static void
-number_blks_r(p)
-	struct block *p;
-{
-	int n;
-
-	if (p == 0 || isMarked(p))
-		return;
-
-	Mark(p);
-	n = n_blocks++;
-	p->id = n;
-	blocks[n] = p;
-
-	number_blks_r(JT(p));
-	number_blks_r(JF(p));
-}
-
-/*
- * Return the number of stmts in the flowgraph reachable by 'p'.
- * The nodes should be unmarked before calling.
- */
-static int
-count_stmts(p)
-	struct block *p;
-{
-	int n;
-
-	if (p == 0 || isMarked(p))
-		return 0;
-	Mark(p);
-	n = count_stmts(JT(p)) + count_stmts(JF(p));
-	return slength(p->stmts) + n + 1;
-}
-
-/*
- * Allocate memory.  All allocation is done before optimization
- * is begun.  A linear bound on the size of all data structures is computed
- * from the total number of blocks and/or statements.
- */
-static void
-opt_init(root)
-	struct block *root;
-{
-	bpf_u_int32 *p;
-	int i, n, max_stmts;
-
-	/*
-	 * First, count the blocks, so we can malloc an array to map
-	 * block number to block.  Then, put the blocks into the array.
-	 */
-	unMarkAll();
-	n = count_blocks(root);
-	blocks = (struct block **)malloc(n * sizeof(*blocks));
-	unMarkAll();
-	n_blocks = 0;
-	number_blks_r(root);
-
-	n_edges = 2 * n_blocks;
-	edges = (struct edge **)malloc(n_edges * sizeof(*edges));
-
-	/*
-	 * The number of levels is bounded by the number of nodes.
-	 */
-	levels = (struct block **)malloc(n_blocks * sizeof(*levels));
-
-	edgewords = n_edges / (8 * sizeof(bpf_u_int32)) + 1;
-	nodewords = n_blocks / (8 * sizeof(bpf_u_int32)) + 1;
-
-	/* XXX */
-	space = (bpf_u_int32 *)malloc(2 * n_blocks * nodewords * sizeof(*space)
-				 + n_edges * edgewords * sizeof(*space));
-	p = space;
-	all_dom_sets = p;
-	for (i = 0; i < n; ++i) {
-		blocks[i]->dom = p;
-		p += nodewords;
-	}
-	all_closure_sets = p;
-	for (i = 0; i < n; ++i) {
-		blocks[i]->closure = p;
-		p += nodewords;
-	}
-	all_edge_sets = p;
-	for (i = 0; i < n; ++i) {
-		register struct block *b = blocks[i];
-
-		b->et.edom = p;
-		p += edgewords;
-		b->ef.edom = p;
-		p += edgewords;
-		b->et.id = i;
-		edges[i] = &b->et;
-		b->ef.id = n_blocks + i;
-		edges[n_blocks + i] = &b->ef;
-		b->et.pred = b;
-		b->ef.pred = b;
-	}
-	max_stmts = 0;
-	for (i = 0; i < n; ++i)
-		max_stmts += slength(blocks[i]->stmts) + 1;
-	/*
-	 * We allocate at most 3 value numbers per statement,
-	 * so this is an upper bound on the number of valnodes
-	 * we'll need.
-	 */
-	maxval = 3 * max_stmts;
-	vmap = (struct vmapinfo *)malloc(maxval * sizeof(*vmap));
-	vnode_base = (struct valnode *)malloc(maxval * sizeof(*vmap));
-}
-
-/*
- * Some pointers used to convert the basic block form of the code,
- * into the array form that BPF requires.  'fstart' will point to
- * the malloc'd array while 'ftail' is used during the recursive traversal.
- */
-static struct bpf_insn *fstart;
-static struct bpf_insn *ftail;
-
-#ifdef BDEBUG
-int bids[1000];
-#endif
-
-/*
- * Returns true if successful.  Returns false if a branch has
- * an offset that is too large.  If so, we have marked that
- * branch so that on a subsequent iteration, it will be treated
- * properly.
- */
-static int
-convert_code_r(p)
-	struct block *p;
-{
-	struct bpf_insn *dst;
-	struct slist *src;
-	int slen;
-	u_int off;
-	int extrajmps;		/* number of extra jumps inserted */
-	struct slist **offset = NULL;
-
-	if (p == 0 || isMarked(p))
-		return (1);
-	Mark(p);
-
-	if (convert_code_r(JF(p)) == 0)
-		return (0);
-	if (convert_code_r(JT(p)) == 0)
-		return (0);
-
-	slen = slength(p->stmts);
-	dst = ftail -= (slen + 1 + p->longjt + p->longjf);
-		/* inflate length by any extra jumps */
-
-	p->offset = dst - fstart;
-
-	/* generate offset[] for convenience  */
-	if (slen) {
-		offset = (struct slist **)calloc(sizeof(struct slist *), slen);
-		if (!offset) {
-			bpf_error("not enough core");
-			/*NOTREACHED*/
-		}
-	}
-	src = p->stmts;
-	for (off = 0; off < slen && src; off++) {
-#if 0
-		printf("off=%d src=%x\n", off, src);
-#endif
-		offset[off] = src;
-		src = src->next;
-	}
-
-	off = 0;
-	for (src = p->stmts; src; src = src->next) {
-		if (src->s.code == NOP)
-			continue;
-		dst->code = (u_short)src->s.code;
-		dst->k = src->s.k;
-
-		/* fill block-local relative jump */
-		if (BPF_CLASS(src->s.code) != BPF_JMP || src->s.code == BPF_JMP|BPF_JA) {
-#if 0
-			if (src->s.jt || src->s.jf) {
-				bpf_error("illegal jmp destination");
-				/*NOTREACHED*/
-			}
-#endif
-			goto filled;
-		}
-		if (off == slen - 2)	/*???*/
-			goto filled;
-
-	    {
-		int i;
-		int jt, jf;
-		char *ljerr = "%s for block-local relative jump: off=%d";
-
-#if 0
-		printf("code=%x off=%d %x %x\n", src->s.code,
-			off, src->s.jt, src->s.jf);
-#endif
-
-		if (!src->s.jt || !src->s.jf) {
-			bpf_error(ljerr, "no jmp destination", off);
-			/*NOTREACHED*/
-		}
-
-		jt = jf = 0;
-		for (i = 0; i < slen; i++) {
-			if (offset[i] == src->s.jt) {
-				if (jt) {
-					bpf_error(ljerr, "multiple matches", off);
-					/*NOTREACHED*/
-				}
-
-				dst->jt = i - off - 1;
-				jt++;
-			}
-			if (offset[i] == src->s.jf) {
-				if (jf) {
-					bpf_error(ljerr, "multiple matches", off);
-					/*NOTREACHED*/
-				}
-				dst->jf = i - off - 1;
-				jf++;
-			}
-		}
-		if (!jt || !jf) {
-			bpf_error(ljerr, "no destination found", off);
-			/*NOTREACHED*/
-		}
-	    }
-filled:
-		++dst;
-		++off;
-	}
-	if (offset)
-		free(offset);
-
-#ifdef BDEBUG
-	bids[dst - fstart] = p->id + 1;
-#endif
-	dst->code = (u_short)p->s.code;
-	dst->k = p->s.k;
-	if (JT(p)) {
-		extrajmps = 0;
-		off = JT(p)->offset - (p->offset + slen) - 1;
-		if (off >= 256) {
-		    /* offset too large for branch, must add a jump */
-		    if (p->longjt == 0) {
-		    	/* mark this instruction and retry */
-			p->longjt++;
-			return(0);
-		    }
-		    /* branch if T to following jump */
-		    dst->jt = extrajmps;
-		    extrajmps++;
-		    dst[extrajmps].code = BPF_JMP|BPF_JA;
-		    dst[extrajmps].k = off - extrajmps;
-		}
-		else
-		    dst->jt = off;
-		off = JF(p)->offset - (p->offset + slen) - 1;
-		if (off >= 256) {
-		    /* offset too large for branch, must add a jump */
-		    if (p->longjf == 0) {
-		    	/* mark this instruction and retry */
-			p->longjf++;
-			return(0);
-		    }
-		    /* branch if F to following jump */
-		    /* if two jumps are inserted, F goes to second one */
-		    dst->jf = extrajmps;
-		    extrajmps++;
-		    dst[extrajmps].code = BPF_JMP|BPF_JA;
-		    dst[extrajmps].k = off - extrajmps;
-		}
-		else
-		    dst->jf = off;
-	}
-	return (1);
-}
-
-
-/*
- * Convert flowgraph intermediate representation to the
- * BPF array representation.  Set *lenp to the number of instructions.
- */
-struct bpf_insn *
-icode_to_fcode(root, lenp)
-	struct block *root;
-	int *lenp;
-{
-	int n;
-	struct bpf_insn *fp;
-
-	/*
-	 * Loop doing convert_codr_r() until no branches remain
-	 * with too-large offsets.
-	 */
-	while (1) {
-	    unMarkAll();
-	    n = *lenp = count_stmts(root);
-    
-	    fp = (struct bpf_insn *)malloc(sizeof(*fp) * n);
-	    memset((char *)fp, 0, sizeof(*fp) * n);
-	    fstart = fp;
-	    ftail = fp + n;
-    
-	    unMarkAll();
-	    if (convert_code_r(root))
-		break;
-	    free(fp);
-	}
-
-	return fp;
-}
-
-#ifdef BDEBUG
-static void
-opt_dump(root)
-	struct block *root;
-{
-	struct bpf_program f;
-
-	memset(bids, 0, sizeof bids);
-	f.bf_insns = icode_to_fcode(root, &f.bf_len);
-	bpf_dump(&f, 1);
-	putchar('\n');
-	free((char *)f.bf_insns);
-}
-#endif