xref: /plan9/sys/src/cmd/spin/pangen4.h (revision f3793cddab66b114d86167a92ff83fb32738958a)
1 /***** spin: pangen4.h *****/
2 
3 /* Copyright (c) 1997-2003 by Lucent Technologies, Bell Laboratories.     */
4 /* All Rights Reserved.  This software is for educational purposes only.  */
5 /* No guarantee whatsoever is expressed or implied by the distribution of */
6 /* this code.  Permission is given to distribute this code provided that  */
7 /* this introductory message is not removed and no monies are exchanged.  */
8 /* Software written by Gerard J. Holzmann.  For tool documentation see:   */
9 /*             http://spinroot.com/                                       */
10 /* Send all bug-reports and/or questions to: bugs@spinroot.com            */
11 
12 /* The DFA code below was written by Anuj Puri and Gerard J. Holzmann in  */
13 /* May 1997, and was inspired by earlier work on data compression using   */
14 /* sharing tree data structures and graph-encoded sets by J-Ch. Gregoire  */
15 /* (INRS Telecom, Quebec, Canada) and D.Zampunieris (Univ.Namur, Belgium) */
16 
17 /* The splay routine code included here is based on the public domain     */
18 /* version written by D. Sleator <sleator@cs.cmu.edu> in 1992.            */
19 
20 static char *Dfa[] = {
21 	"#ifdef MA",
22 	"/*",
23 	"#include <stdio.h>",
24 	"#define uchar	unsigned char",
25 	"*/",
26 	"#define ulong	unsigned long",
27 	"#define ushort	unsigned short",
28 	"",
29 	"#define TWIDTH		256",
30 	"#define HASH(y,n)	(n)*(((long)y))",
31 	"#define INRANGE(e,h)	((h>=e->From && h<=e->To)||(e->s==1 && e->S==h))",
32 	"",
33 	"extern char	*emalloc(unsigned long);	/* imported routine  */",
34 	"extern void	dfa_init(ushort);	/* 4 exported routines */",
35 	"extern int	dfa_member(ulong);",
36 	"extern int	dfa_store(uchar *);",
37 	"extern void	dfa_stats(void);",
38 	"",
39 	"typedef struct Edge {",
40 	"	uchar From, To;		/* max range 0..255 */",
41 	"	uchar s, S;		/* if s=1, S is singleton */",
42 	"	struct Vertex	*Dst;",
43 	"	struct Edge	*Nxt;",
44 	"} Edge;",
45 	"",
46 	"typedef struct Vertex {",
47 	"	ulong	key, num;	/* key for splay tree, nr incoming edges */",
48 	"	uchar	from[2], to[2];	/* in-node predefined edge info    */",
49 	"	struct	Vertex	*dst[2];/* most nodes have 2 or more edges */",
50 	"	struct	Edge	*Succ;	/* in case there are more edges */",
51 	"	struct	Vertex	*lnk, *left, *right; /* splay tree plumbing */",
52 	"} Vertex;",
53 	"",
54 	"static Edge	*free_edges;",
55 	"static Vertex	*free_vertices;",
56 	"static Vertex	**layers;	/* one splay tree of nodes per layer */",
57 	"static Vertex	**path;		/* run of word in the DFA */",
58 	"static Vertex	*R, *F, *NF;	/* Root, Final, Not-Final */",
59 	"static uchar	*word, *lastword;/* string, and last string inserted */",
60 	"static int	dfa_depth, iv=0, nv=0, pfrst=0, Tally;",
61 	"",
62 	"static void	insert_it(Vertex *, int);	/* splay-tree code */",
63 	"static void	delete_it(Vertex *, int);",
64 	"static Vertex	*find_it(Vertex *, Vertex *, uchar, int);",
65 	"",
66 	"static void",
67 	"recyc_edges(Edge *e)",
68 	"{",
69 	"	if (!e) return;",
70 	"	recyc_edges(e->Nxt);",
71 	"	e->Nxt = free_edges;",
72 	"	free_edges = e;",
73 	"}",
74 	"",
75 	"static Edge *",
76 	"new_edge(Vertex *dst)",
77 	"{	Edge *e;",
78 	"",
79 	"	if (free_edges)",
80 	"	{	e = free_edges;",
81 	"		free_edges = e->Nxt;",
82 	"		e->From = e->To = e->s = e->S = 0;",
83 	"		e->Nxt = (Edge *) 0;",
84 	"	} else",
85 	"		e = (Edge *) emalloc(sizeof(Edge));",
86 	"	e->Dst = dst;",
87 	"",
88 	"	return e;",
89 	"}",
90 	"",
91 	"static void",
92 	"recyc_vertex(Vertex *v)",
93 	"{",
94 	"	recyc_edges(v->Succ);",
95 	"	v->Succ = (Edge *) free_vertices;",
96 	"	free_vertices = v;",
97 	"	nr_states--;",
98 	"}",
99 	"",
100 	"static Vertex *",
101 	"new_vertex(void)",
102 	"{	Vertex *v;",
103 	"",
104 	"	if (free_vertices)",
105 	"	{	v = free_vertices;",
106 	"		free_vertices = (Vertex *) v->Succ;",
107 	"		v->Succ = (Edge *) 0;",
108 	"		v->num  = 0;",
109 	"	} else",
110 	"		v = (Vertex *) emalloc(sizeof(Vertex));",
111 	"",
112 	"	nr_states++;",
113 	"	return v; ",
114 	"}",
115 	"",
116 	"static Vertex *",
117 	"allDelta(Vertex *v, int n)",
118 	"{	Vertex *dst = new_vertex();",
119 	"",
120 	"	v->from[0] = 0;",
121 	"	v->to[0] = 255;",
122 	"	v->dst[0] = dst;",
123 	"	dst->num = 256;",
124 	"	insert_it(v, n);",
125 	"	return dst;",
126 	"}",
127 	"",
128 	"static void",
129 	"insert_edge(Vertex *v, Edge *e)",
130 	"{	/* put new edge first */",
131 	"	if (!v->dst[0])",
132 	"	{	v->dst[0] = e->Dst;",
133 	"		v->from[0] = e->From;",
134 	"		v->to[0] = e->To;",
135 	"		recyc_edges(e);",
136 	"		return;",
137 	"	}",
138 	"	if (!v->dst[1])",
139 	"	{	v->from[1] = v->from[0]; v->from[0] = e->From;",
140 	"		v->to[1]   = v->to[0];   v->to[0]   = e->To;",
141 	"		v->dst[1]  = v->dst[0];  v->dst[0]  = e->Dst;",
142 	"		recyc_edges(e);",
143 	"		return;",
144 	"	} /* shift */",
145 	"	{	int f      = v->from[1];",
146 	"		int t      = v->to[1];",
147 	"		Vertex *d  = v->dst[1];",
148 	"		v->from[1] = v->from[0]; v->from[0] = e->From;",
149 	"		v->to[1]   = v->to[0];   v->to[0]   = e->To;",
150 	"		v->dst[1]  = v->dst[0];  v->dst[0]  = e->Dst;",
151 	"		e->From = f;",
152 	"		e->To   = t;",
153 	"		e->Dst  = d;",
154 	"	}",
155 	"	e->Nxt = v->Succ;",
156 	"	v->Succ = e;",
157 	"}",
158 	"",
159 	"static void",
160 	"copyRecursive(Vertex *v, Edge *e)",
161 	"{	Edge *f;",
162 	"	if (e->Nxt) copyRecursive(v, e->Nxt);",
163 	"	f = new_edge(e->Dst);",
164 	"	f->From = e->From;",
165 	"	f->To   = e->To;",
166 	"	f->s    = e->s;",
167 	"	f->S    = e->S;",
168 	"	f->Nxt  = v->Succ;",
169 	"	v->Succ = f;",
170 	"}",
171 	"",
172 	"static void",
173 	"copyEdges(Vertex *to, Vertex *from)",
174 	"{	int i;",
175 	"	for (i = 0; i < 2; i++)",
176 	"	{	to->from[i] = from->from[i];",
177 	"		to->to[i]   = from->to[i];",
178 	"		to->dst[i]  = from->dst[i];",
179 	"	}",
180 	"	if (from->Succ) copyRecursive(to, from->Succ);",
181 	"}",
182 	"",
183 	"static Edge *",
184 	"cacheDelta(Vertex *v, int h, int first)",
185 	"{	static Edge *ov, tmp;  int i;",
186 	"",
187 	"	if (!first && INRANGE(ov,h))",
188 	"		return ov; /* intercepts about 10%% */",
189 	"	for (i = 0; i < 2; i++)",
190 	"		if (v->dst[i] && h >= v->from[i] && h <= v->to[i])",
191 	"		{	tmp.From = v->from[i];",
192 	"			tmp.To   = v->to[i];",
193 	"			tmp.Dst  = v->dst[i];",
194 	"			tmp.s    =  tmp.S = 0;",
195 	"			ov = &tmp;",
196 	"			return ov;",
197 	"		}",
198 	"	for (ov = v->Succ; ov; ov = ov->Nxt)",
199 	"		if (INRANGE(ov,h)) return ov;",
200 	"",
201 	"	Uerror(\"cannot get here, cacheDelta\");",
202 	"	return (Edge *) 0;",
203 	"}",
204 	"",
205 	"static Vertex *",
206 	"Delta(Vertex *v, int h)	/* v->delta[h] */",
207 	"{	Edge *e;",
208 	"",
209 	"	if (v->dst[0] && h >= v->from[0] && h <= v->to[0])",
210 	"		return v->dst[0];	/* oldest edge */",
211 	"	if (v->dst[1] && h >= v->from[1] && h <= v->to[1])",
212 	"		return v->dst[1];",
213 	"	for (e = v->Succ; e; e = e->Nxt)",
214 	"		if (INRANGE(e,h))",
215 	"			return e->Dst;",
216 	"	Uerror(\"cannot happen Delta\");",
217 	"	return (Vertex *) 0;",
218 	"}",
219 	"",
220 	"static void",
221 	"numDelta(Vertex *v, int d)",
222 	"{	Edge *e;",
223 	"	ulong cnt;",
224 	"	int i;",
225 	"",
226 	"	for (i = 0; i < 2; i++)",
227 	"	if (v->dst[i])",
228 	"	{	cnt = v->dst[i]->num + d*(1 + v->to[i] - v->from[i]);",
229 	"		if (d == 1 && cnt < v->dst[i]->num) goto bad;",
230 	"		v->dst[i]->num = cnt;",
231 	"	}",
232 	"	for (e = v->Succ; e; e = e->Nxt)",
233 	"	{	cnt = e->Dst->num + d*(1 + e->To - e->From + e->s);",
234 	"		if (d == 1 && cnt < e->Dst->num)",
235 	"bad:			Uerror(\"too many incoming edges\");",
236 	"		e->Dst->num = cnt;",
237 	"	}",
238 	"}",
239 	"",
240 	"static void",
241 	"setDelta(Vertex *v, int h, Vertex *newdst)	/* v->delta[h] = newdst; */",
242 	"{	Edge *e, *f = (Edge *) 0, *g;",
243 	"	int i;",
244 	"",
245 	"	/* remove the old entry, if there */",
246 	"	for (i = 0; i < 2; i++)",
247 	"		if (v->dst[i] && h >= v->from[i] && h <= v->to[i])",
248 	"		{	if (h == v->from[i])",
249 	"			{	if (h == v->to[i])",
250 	"				{	v->dst[i] = (Vertex *) 0;",
251 	"					v->from[i] = v->to[i] = 0;",
252 	"				} else",
253 	"					v->from[i]++;",
254 	"			} else if (h == v->to[i])",
255 	"			{	v->to[i]--;",
256 	"			} else",
257 	"			{	g = new_edge(v->dst[i]);/* same dst */",
258 	"				g->From    = v->from[i];",
259 	"				g->To      = h-1;	/* left half */",
260 	"				v->from[i] = h+1;	/* right half */",
261 	"				insert_edge(v, g);",
262 	"			}",
263 	"			goto part2;",
264 	"		}",
265 	"	for (e = v->Succ; e; f = e, e = e->Nxt)",
266 	"	{	if (e->s == 1 && e->S == h)",
267 	"		{	e->s = e->S = 0;",
268 	"			goto rem_tst;",
269 	"		}",
270 	"		if (h >= e->From && h <= e->To)",
271 	"		{	if (h == e->From)",
272 	"			{	if (h == e->To)",
273 	"				{	if (e->s)",
274 	"					{	e->From = e->To = e->S;",
275 	"						e->s = 0;",
276 	"						break;",
277 	"					} else",
278 	"						goto rem_do;",
279 	"				} else",
280 	"					e->From++;",
281 	"			} else if (h == e->To)",
282 	"			{	e->To--;",
283 	"			} else				/* split */",
284 	"			{	g = new_edge(e->Dst);	/* same dst */",
285 	"				g->From = e->From;",
286 	"				g->To   = h-1;		/* g=left half */",
287 	"				e->From = h+1;		/* e=right half */",
288 	"				g->Nxt  = e->Nxt;	/* insert g */",
289 	"				e->Nxt  = g;		/* behind e */",
290 	"				break;			/* done */",
291 	"			}",
292 	"",
293 	"rem_tst:		if (e->From > e->To)",
294 	"			{	if (e->s == 0) {",
295 	"rem_do:				if (f)",
296 	"						f->Nxt = e->Nxt;",
297 	"					else",
298 	"						v->Succ = e->Nxt;",
299 	"					e->Nxt = (Edge *) 0;",
300 	"					recyc_edges(e);",
301 	"				} else",
302 	"				{	e->From = e->To = e->S;",
303 	"					e->s = 0;",
304 	"			}	}",
305 	"			break;",
306 	"	}	}",
307 	"part2:",
308 	"	/* check if newdst is already there */",
309 	"	for (i = 0; i < 2; i++)",
310 	"		if (v->dst[i] == newdst)",
311 	"		{	if (h+1 == (int) v->from[i])",
312 	"			{	v->from[i] = h;",
313 	"				return;",
314 	"			}",
315 	"			if (h == (int) v->to[i]+1)",
316 	"			{	v->to[i] = h;",
317 	"				return;",
318 	"		}	}",
319 	"	for (e = v->Succ; e; e = e->Nxt)",
320 	"	{	if (e->Dst == newdst)",
321 	"		{	if (h+1 == (int) e->From)",
322 	"			{	e->From = h;",
323 	"				if (e->s == 1 && e->S+1 == e->From)",
324 	"				{	e->From = e->S;",
325 	"					e->s = e->S = 0;",
326 	"				}",
327 	"				return;",
328 	"			}",
329 	"			if (h == (int) e->To+1)",
330 	"			{	e->To = h;",
331 	"				if (e->s == 1 && e->S == e->To+1)",
332 	"				{	e->To = e->S;",
333 	"					e->s = e->S = 0;",
334 	"				}",
335 	"				return;",
336 	"			}",
337 	"			if (e->s == 0)",
338 	"			{	e->s = 1;",
339 	"				e->S = h;",
340 	"				return;",
341 	"	}	}	}",
342 	"	/* add as a new edge */",
343 	"	e = new_edge(newdst);",
344 	"	e->From = e->To = h;",
345 	"	insert_edge(v, e);",
346 	"}",
347 	"",
348 	"static ulong",
349 	"cheap_key(Vertex *v)",
350 	"{	ulong vk2 = 0;",
351 	"",
352 	"	if (v->dst[0])",
353 	"	{	vk2 = (ulong) v->dst[0];",
354 	"		if ((ulong) v->dst[1] > vk2)",
355 	"			vk2 = (ulong) v->dst[1];",
356 	"	} else if (v->dst[1])",
357 	"		vk2 = (ulong) v->dst[1]; ",
358 	"	if (v->Succ)",
359 	"	{	Edge *e;",
360 	"		for (e = v->Succ; e; e = e->Nxt)",
361 	"			if ((ulong) e->Dst > vk2)",
362 	"				vk2 = (ulong) e->Dst;",
363 	"	}",
364 	"	Tally = (vk2>>2)&(TWIDTH-1);",
365 	"	return v->key;",
366 	"}",
367 	"",
368 	"static ulong",
369 	"mk_key(Vertex *v)	/* not sensitive to order */",
370 	"{	ulong m = 0, vk2 = 0;",
371 	"	Edge *e;",
372 	"",
373 	"	if (v->dst[0])",
374 	"	{	m += HASH(v->dst[0], v->to[0] - v->from[0] + 1);",
375 	"		vk2 = (ulong) v->dst[0]; ",
376 	"	}",
377 	"	if (v->dst[1])",
378 	"	{	m += HASH(v->dst[1], v->to[1] - v->from[1] + 1);",
379 	"		if ((ulong) v->dst[1] > vk2) vk2 = (ulong) v->dst[1]; ",
380 	"	}",
381 	"	for (e = v->Succ; e; e = e->Nxt)",
382 	"	{	m += HASH(e->Dst, e->To - e->From + 1 + e->s);",
383 	"		if ((ulong) e->Dst > vk2) vk2 = (ulong) e->Dst; ",
384 	"	}",
385 	"	Tally = (vk2>>2)&(TWIDTH-1);",
386 	"	return m;",
387 	"}",
388 	"",
389 	"static ulong",
390 	"mk_special(int sigma, Vertex *n, Vertex *v)",
391 	"{	ulong m = 0, vk2 = 0;",
392 	"	Edge *f;",
393 	"	int i;",
394 	"",
395 	"	for (i = 0; i < 2; i++)",
396 	"		if (v->dst[i])",
397 	"		{	if (sigma >= v->from[i] && sigma <= v->to[i])",
398 	"			{	m += HASH(v->dst[i], v->to[i]-v->from[i]);",
399 	"				if ((ulong) v->dst[i] > vk2",
400 	"				&&   v->to[i] > v->from[i])",
401 	"					vk2 = (ulong) v->dst[i]; ",
402 	"			} else",
403 	"			{	m += HASH(v->dst[i], v->to[i]-v->from[i]+1);",
404 	"				if ((ulong) v->dst[i] > vk2)",
405 	"					vk2 = (ulong) v->dst[i]; ",
406 	"		}	}",
407 	"	for (f = v->Succ; f; f = f->Nxt)",
408 	"	{	if (sigma >= f->From && sigma <= f->To)",
409 	"		{	m += HASH(f->Dst, f->To - f->From + f->s);",
410 	"			if ((ulong) f->Dst > vk2",
411 	"			&&   f->To - f->From + f->s > 0)",
412 	"				vk2 = (ulong) f->Dst; ",
413 	"		} else if (f->s == 1 && sigma == f->S)",
414 	"		{	m += HASH(f->Dst, f->To - f->From + 1);",
415 	"			if ((ulong) f->Dst > vk2) vk2 = (ulong) f->Dst; ",
416 	"		} else",
417 	"		{	m += HASH(f->Dst, f->To - f->From + 1 + f->s);",
418 	"			if ((ulong) f->Dst > vk2) vk2 = (ulong) f->Dst; ",
419 	"	}	}",
420 	"",
421 	"	if ((ulong) n > vk2) vk2 = (ulong) n; ",
422 	"	Tally = (vk2>>2)&(TWIDTH-1);",
423 	"	m += HASH(n, 1);",
424 	"	return m;",
425 	"}",
426 	"",
427 	"void ",
428 	"dfa_init(ushort nr_layers)",
429 	"{	int i; Vertex *r, *t;",
430 	"",
431 	"	dfa_depth = nr_layers;	/* one byte per layer */",
432 	"	path   = (Vertex **) emalloc((dfa_depth+1)*sizeof(Vertex *));",
433 	"	layers = (Vertex **) emalloc(TWIDTH*(dfa_depth+1)*sizeof(Vertex *));",
434 	"	lastword = (uchar *) emalloc((dfa_depth+1)*sizeof(uchar));",
435 	"	lastword[dfa_depth] = lastword[0] = 255;",
436 	"	path[0] = R = new_vertex(); F = new_vertex();",
437 	"",
438 	"	for (i = 1, r = R; i < dfa_depth; i++, r = t)",
439 	"		t = allDelta(r, i-1);",
440 	"	NF = allDelta(r, i-1);",
441 	"}",
442 	"",
443 	"#if 0",
444 	"static void complement_dfa(void) { Vertex *tmp = F; F = NF; NF = tmp; }",
445 	"#endif",
446 	"",
447 	"double",
448 	"tree_stats(Vertex *t)",
449 	"{	Edge *e; double cnt=0.0;",
450 	"	if (!t) return 0;",
451 	"	if (!t->key) return 0;",
452 	"	t->key = 0; /* precaution */",
453 	"	if (t->dst[0]) cnt++;",
454 	"	if (t->dst[1]) cnt++;",
455 	"	for (e = t->Succ; e; e = e->Nxt)",
456 	"		cnt++;",
457 	"	cnt += tree_stats(t->lnk);",
458 	"	cnt += tree_stats(t->left);",
459 	"	cnt += tree_stats(t->right);",
460 	"	return cnt;",
461 	"}",
462 	"",
463 	"void",
464 	"dfa_stats(void)",
465 	"{	int i, j; double cnt = 0.0;",
466 	"	for (j = 0; j < TWIDTH; j++)",
467 	"	for (i = 0; i < dfa_depth+1; i++)",
468 	"		cnt += tree_stats(layers[i*TWIDTH+j]);",
469 	"	printf(\"Minimized Automaton:\t%%6d nodes and %%6g edges\\n\",",
470 	"		nr_states, cnt);",
471 	"}",
472 	"",
473 	"int",
474 	"dfa_member(ulong n)",
475 	"{	Vertex **p, **q;",
476 	"	uchar *w = &word[n];",
477 	"	int i;",
478 	"",
479 	"	p = &path[n]; q = (p+1);",
480 	"	for (i = n; i < dfa_depth; i++)",
481 	"		*q++ = Delta(*p++, *w++);",
482 	"	return (*p == F);",
483 	"}",
484 	"",
485 	"int",
486 	"dfa_store(uchar *sv)",
487 	"{	Vertex **p, **q, *s, *y, *old, *new = F;",
488 	"	uchar *w, *u = lastword;",
489 	"	int i, j, k;",
490 	"",
491 	"	w = word = sv;",
492 	"	while (*w++ == *u++)	/* find first byte that differs */",
493 	"		;",
494 	"	pfrst = (int) (u - lastword) - 1;",
495 	"	memcpy(&lastword[pfrst], &sv[pfrst], dfa_depth-pfrst);",
496 	"	if (pfrst > iv) pfrst = iv;",
497 	"	if (pfrst > nv) pfrst = nv;",
498 	"/* phase1: */",
499 	"	p = &path[pfrst]; q = (p+1); w = &word[pfrst];",
500 	"	for (i = pfrst; i < dfa_depth; i++)",
501 	"		*q++ = Delta(*p++, *w++);	/* (*p)->delta[*w++]; */",
502 	"",
503 	"	if (*p == F) return 1;	/* it's already there */",
504 	"/* phase2: */",
505 	"	iv = dfa_depth;",
506 	"	do {	iv--;",
507 	"		old = new;",
508 	"		new = find_it(path[iv], old, word[iv], iv);",
509 	"	} while (new && iv > 0);",
510 	"",
511 	"/* phase3: */",
512 	"	nv = k = 0; s = path[0];",
513 	"	for (j = 1; j <= iv; ++j) ",
514 	"		if (path[j]->num > 1)",
515 	"		{	y = new_vertex();",
516 	"			copyEdges(y, path[j]);",
517 	"			insert_it(y, j);",
518 	"			numDelta(y, 1);",
519 	"			delete_it(s, j-1);",
520 	"			setDelta(s, word[j-1], y);",
521 	"			insert_it(s, j-1);",
522 	"			y->num = 1;	/* initial value 1 */",
523 	"			s = y;",
524 	"			path[j]->num--;	/* only 1 moved from j to y */",
525 	"			k = 1;",
526 	"		} else",
527 	"		{	s = path[j];",
528 	"			if (!k) nv = j;",
529 	"		}",
530 	"	y = Delta(s, word[iv]);",
531 	"	y->num--;",
532 	"	delete_it(s, iv); ",
533 	"	setDelta(s, word[iv], old);",
534 	"	insert_it(s, iv); ",
535 	"	old->num++;",
536 	"",
537 	"	for (j = iv+1; j < dfa_depth; j++)",
538 	"		if (path[j]->num == 0)",
539 	"		{	numDelta(path[j], -1);",
540 	"			delete_it(path[j], j);",
541 	"			recyc_vertex(path[j]);",
542 	"		} else",
543 	"			break;",
544 	"	return 0;",
545 	"}",
546 	"",
547 	"static Vertex *",
548 	"splay(ulong i, Vertex *t)",
549 	"{	Vertex N, *l, *r, *y;",
550 	"",
551 	"	if (!t) return t;",
552 	"	N.left = N.right = (Vertex *) 0;",
553 	"	l = r = &N;",
554 	"	for (;;)",
555 	"	{	if (i < t->key)",
556 	"		{	if (!t->left) break;",
557 	"			if (i < t->left->key)",
558 	"			{	y = t->left;",
559 	"				t->left = y->right;",
560 	"				y->right = t;",
561 	"				t = y;",
562 	"				if (!t->left) break;",
563 	"			}",
564 	"			r->left = t;",
565 	"			r = t;",
566 	"			t = t->left;",
567 	"		} else if (i > t->key)",
568 	"		{	if (!t->right) break;",
569 	"			if (i > t->right->key)",
570 	"			{	y = t->right;",
571 	"				t->right = y->left;",
572 	"				y->left = t;",
573 	"				t = y;",
574 	"				if (!t->right) break;",
575 	"			}",
576 	"			l->right = t;",
577 	"			l = t;",
578 	"			t = t->right;",
579 	"		} else",
580 	"			break;",
581 	"	}",
582 	"	l->right = t->left;",
583 	"	r->left = t->right;",
584 	"	t->left = N.right;",
585 	"	t->right = N.left;",
586 	"	return t;",
587 	"}",
588 	"",
589 	"static void",
590 	"insert_it(Vertex *v, int L)",
591 	"{	Vertex *new, *t;",
592 	"	ulong i; int nr;",
593 	"",
594 	"	i = mk_key(v);",
595 	"	nr = ((L*TWIDTH)+Tally);",
596 	"	t = layers[nr];",
597 	"",
598 	"	v->key = i; ",
599 	"	if (!t)",
600 	"	{	layers[nr] = v;",
601 	"		return;",
602 	"	}",
603 	"	t = splay(i, t);",
604 	"	if (i < t->key)",
605 	"	{	new = v;",
606 	"		new->left = t->left;",
607 	"		new->right = t;",
608 	"		t->left = (Vertex *) 0;",
609 	"	} else if (i > t->key)",
610 	"	{	new = v;",
611 	"		new->right = t->right;",
612 	"		new->left = t;",
613 	"		t->right = (Vertex *) 0;",
614 	"	} else	 /* it's already there */",
615 	"	{	v->lnk = t->lnk; /* put in linked list off v */",
616 	"		t->lnk = v;",
617 	"		new = t;",
618 	"	}",
619 	"	layers[nr] = new;",
620 	"}",
621 	"",
622 	"static int",
623 	"checkit(Vertex *h, Vertex *v, Vertex *n, uchar sigma)",
624 	"{	Edge *g, *f;",
625 	"	int i, k, j = 1;",
626 	"",
627 	"	for (k = 0; k < 2; k++)",
628 	"		if (h->dst[k])",
629 	"		{	if (sigma >= h->from[k] && sigma <= h->to[k])",
630 	"			{	if (h->dst[k] != n) goto no_match;",
631 	"			}",
632 	"			for (i = h->from[k]; i <= h->to[k]; i++)",
633 	"			{	if (i == sigma) continue;",
634 	"				g = cacheDelta(v, i, j); j = 0;",
635 	"				if (h->dst[k] != g->Dst)",
636 	"					goto no_match;",
637 	"				if (g->s == 0 || g->S != i)",
638 	"					i = g->To;",
639 	"		}	}",
640 	"	for (f = h->Succ; f; f = f->Nxt)",
641 	"	{	if (INRANGE(f,sigma))",
642 	"		{	if (f->Dst != n) goto no_match;",
643 	"		}",
644 	"		for (i = f->From; i <= f->To; i++)",
645 	"		{	if (i == sigma) continue;",
646 	"			g = cacheDelta(v, i, j); j = 0;",
647 	"			if (f->Dst != g->Dst)",
648 	"				goto no_match;",
649 	"			if (g->s == 1 && i == g->S)",
650 	"				continue;",
651 	"			i = g->To;",
652 	"		}",
653 	"		if (f->s && f->S != sigma)",
654 	"		{	g = cacheDelta(v, f->S, 1);",
655 	"			if (f->Dst != g->Dst)",
656 	"				goto no_match;",
657 	"		}",
658 	"	}",
659 	"	if (h->Succ || h->dst[0] || h->dst[1]) return 1;",
660 	"no_match:",
661 	"	return 0;",
662 	"}",
663 	"",
664 	"static Vertex *",
665 	"find_it(Vertex *v, Vertex *n, uchar sigma, int L)",
666 	"{	Vertex *z, *t;",
667 	"	ulong i; int nr;",
668 	"",
669 	"	i = mk_special(sigma,n,v);",
670 	"	nr = ((L*TWIDTH)+Tally);",
671 	"	t = layers[nr];",
672 	"",
673 	"	if (!t) return (Vertex *) 0;",
674 	"	layers[nr] = t = splay(i, t);",
675 	"	if (i == t->key)",
676 	"	for (z = t; z; z = z->lnk)",
677 	"		if (checkit(z, v, n, sigma))",
678 	"			return z;",
679 	"",
680 	"	return (Vertex *) 0;",
681 	"}",
682 	"",
683 	"static void",
684 	"delete_it(Vertex *v, int L)",
685 	"{	Vertex *x, *t;",
686 	"	ulong i; int nr;",
687 	"",
688 	"	i = cheap_key(v);",
689 	"	nr = ((L*TWIDTH)+Tally);",
690 	"	t = layers[nr];",
691 	"	if (!t) return;",
692 	"",
693 	"	t = splay(i, t);",
694 	"	if (i == t->key)",
695 	"	{	Vertex *z, *y = (Vertex *) 0;",
696 	"		for (z = t; z && z != v; y = z, z = z->lnk)",
697 	"			;",
698 	"		if (z != v) goto bad;",
699 	"		if (y)",
700 	"		{	y->lnk = z->lnk;",
701 	"			z->lnk = (Vertex *) 0;",
702 	"			layers[nr] = t;",
703 	"			return;",
704 	"		} else if (z->lnk)	/* z == t == v */",
705 	"		{	y = z->lnk;",
706 	"			y->left = t->left;",
707 	"			y->right = t->right;",
708 	"			t->left = t->right = t->lnk = (Vertex *) 0;",
709 	"			layers[nr] = y;",
710 	"			return;",
711 	"		}",
712 	"		/* delete the node itself */",
713 	"		if (!t->left)",
714 	"		{	x = t->right;",
715 	"		} else",
716 	"		{	x = splay(i, t->left);",
717 	"			x->right = t->right;",
718 	"		}",
719 	"		t->left = t->right = t->lnk = (Vertex *) 0;",
720 	"		layers[nr] = x;",
721 	"		return;",
722 	"	}",
723 	"bad:	Uerror(\"cannot happen delete\");",
724 	"}",
725 	"#endif", /* MA */
726 	0,
727 };
728