xref: /freebsd/cddl/contrib/opensolaris/lib/libdtrace/common/dt_cc.c (revision 6ba2210ee039f2f12878c217bcf058e9c8b26b29)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
24  * Copyright (c) 2011, 2016 by Delphix. All rights reserved.
25  * Copyright (c) 2013, Joyent Inc. All rights reserved.
26  * Copyright 2015 Gary Mills
27  */
28 
29 /*
30  * DTrace D Language Compiler
31  *
32  * The code in this source file implements the main engine for the D language
33  * compiler.  The driver routine for the compiler is dt_compile(), below.  The
34  * compiler operates on either stdio FILEs or in-memory strings as its input
35  * and can produce either dtrace_prog_t structures from a D program or a single
36  * dtrace_difo_t structure from a D expression.  Multiple entry points are
37  * provided as wrappers around dt_compile() for the various input/output pairs.
38  * The compiler itself is implemented across the following source files:
39  *
40  * dt_lex.l - lex scanner
41  * dt_grammar.y - yacc grammar
42  * dt_parser.c - parse tree creation and semantic checking
43  * dt_decl.c - declaration stack processing
44  * dt_xlator.c - D translator lookup and creation
45  * dt_ident.c - identifier and symbol table routines
46  * dt_pragma.c - #pragma processing and D pragmas
47  * dt_printf.c - D printf() and printa() argument checking and processing
48  * dt_cc.c - compiler driver and dtrace_prog_t construction
49  * dt_cg.c - DIF code generator
50  * dt_as.c - DIF assembler
51  * dt_dof.c - dtrace_prog_t -> DOF conversion
52  *
53  * Several other source files provide collections of utility routines used by
54  * these major files.  The compiler itself is implemented in multiple passes:
55  *
56  * (1) The input program is scanned and parsed by dt_lex.l and dt_grammar.y
57  *     and parse tree nodes are constructed using the routines in dt_parser.c.
58  *     This node construction pass is described further in dt_parser.c.
59  *
60  * (2) The parse tree is "cooked" by assigning each clause a context (see the
61  *     routine dt_setcontext(), below) based on its probe description and then
62  *     recursively descending the tree performing semantic checking.  The cook
63  *     routines are also implemented in dt_parser.c and described there.
64  *
65  * (3) For actions that are DIF expression statements, the DIF code generator
66  *     and assembler are invoked to create a finished DIFO for the statement.
67  *
68  * (4) The dtrace_prog_t data structures for the program clauses and actions
69  *     are built, containing pointers to any DIFOs created in step (3).
70  *
71  * (5) The caller invokes a routine in dt_dof.c to convert the finished program
72  *     into DOF format for use in anonymous tracing or enabling in the kernel.
73  *
74  * In the implementation, steps 2-4 are intertwined in that they are performed
75  * in order for each clause as part of a loop that executes over the clauses.
76  *
77  * The D compiler currently implements nearly no optimization.  The compiler
78  * implements integer constant folding as part of pass (1), and a set of very
79  * simple peephole optimizations as part of pass (3).  As with any C compiler,
80  * a large number of optimizations are possible on both the intermediate data
81  * structures and the generated DIF code.  These possibilities should be
82  * investigated in the context of whether they will have any substantive effect
83  * on the overall DTrace probe effect before they are undertaken.
84  */
85 
86 #include <sys/types.h>
87 #include <sys/wait.h>
88 #include <sys/sysmacros.h>
89 
90 #include <assert.h>
91 #include <string.h>
92 #include <strings.h>
93 #include <signal.h>
94 #include <unistd.h>
95 #include <stdlib.h>
96 #include <stdio.h>
97 #include <errno.h>
98 #include <ucontext.h>
99 #include <limits.h>
100 #include <ctype.h>
101 #include <dirent.h>
102 #include <dt_module.h>
103 #include <dt_program.h>
104 #include <dt_provider.h>
105 #include <dt_printf.h>
106 #include <dt_pid.h>
107 #include <dt_grammar.h>
108 #include <dt_ident.h>
109 #include <dt_string.h>
110 #include <dt_impl.h>
111 
112 static const dtrace_diftype_t dt_void_rtype = {
113 	DIF_TYPE_CTF, CTF_K_INTEGER, 0, 0, 0
114 };
115 
116 static const dtrace_diftype_t dt_int_rtype = {
117 	DIF_TYPE_CTF, CTF_K_INTEGER, 0, 0, sizeof (uint64_t)
118 };
119 
120 static void *dt_compile(dtrace_hdl_t *, int, dtrace_probespec_t, void *,
121     uint_t, int, char *const[], FILE *, const char *);
122 
123 /*ARGSUSED*/
124 static int
125 dt_idreset(dt_idhash_t *dhp, dt_ident_t *idp, void *ignored)
126 {
127 	idp->di_flags &= ~(DT_IDFLG_REF | DT_IDFLG_MOD |
128 	    DT_IDFLG_DIFR | DT_IDFLG_DIFW);
129 	return (0);
130 }
131 
132 /*ARGSUSED*/
133 static int
134 dt_idpragma(dt_idhash_t *dhp, dt_ident_t *idp, void *ignored)
135 {
136 	yylineno = idp->di_lineno;
137 	xyerror(D_PRAGMA_UNUSED, "unused #pragma %s\n", (char *)idp->di_iarg);
138 	return (0);
139 }
140 
141 static dtrace_stmtdesc_t *
142 dt_stmt_create(dtrace_hdl_t *dtp, dtrace_ecbdesc_t *edp,
143     dtrace_attribute_t descattr, dtrace_attribute_t stmtattr)
144 {
145 	dtrace_stmtdesc_t *sdp = dtrace_stmt_create(dtp, edp);
146 
147 	if (sdp == NULL)
148 		longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
149 
150 	assert(yypcb->pcb_stmt == NULL);
151 	yypcb->pcb_stmt = sdp;
152 
153 	sdp->dtsd_descattr = descattr;
154 	sdp->dtsd_stmtattr = stmtattr;
155 
156 	return (sdp);
157 }
158 
159 static dtrace_actdesc_t *
160 dt_stmt_action(dtrace_hdl_t *dtp, dtrace_stmtdesc_t *sdp)
161 {
162 	dtrace_actdesc_t *new;
163 
164 	if ((new = dtrace_stmt_action(dtp, sdp)) == NULL)
165 		longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
166 
167 	return (new);
168 }
169 
170 /*
171  * Utility function to determine if a given action description is destructive.
172  * The dtdo_destructive bit is set for us by the DIF assembler (see dt_as.c).
173  */
174 static int
175 dt_action_destructive(const dtrace_actdesc_t *ap)
176 {
177 	return (DTRACEACT_ISDESTRUCTIVE(ap->dtad_kind) || (ap->dtad_kind ==
178 	    DTRACEACT_DIFEXPR && ap->dtad_difo->dtdo_destructive));
179 }
180 
181 static void
182 dt_stmt_append(dtrace_stmtdesc_t *sdp, const dt_node_t *dnp)
183 {
184 	dtrace_ecbdesc_t *edp = sdp->dtsd_ecbdesc;
185 	dtrace_actdesc_t *ap, *tap;
186 	int commit = 0;
187 	int speculate = 0;
188 	int datarec = 0;
189 
190 	/*
191 	 * Make sure that the new statement jibes with the rest of the ECB.
192 	 */
193 	for (ap = edp->dted_action; ap != NULL; ap = ap->dtad_next) {
194 		if (ap->dtad_kind == DTRACEACT_COMMIT) {
195 			if (commit) {
196 				dnerror(dnp, D_COMM_COMM, "commit( ) may "
197 				    "not follow commit( )\n");
198 			}
199 
200 			if (datarec) {
201 				dnerror(dnp, D_COMM_DREC, "commit( ) may "
202 				    "not follow data-recording action(s)\n");
203 			}
204 
205 			for (tap = ap; tap != NULL; tap = tap->dtad_next) {
206 				if (!DTRACEACT_ISAGG(tap->dtad_kind))
207 					continue;
208 
209 				dnerror(dnp, D_AGG_COMM, "aggregating actions "
210 				    "may not follow commit( )\n");
211 			}
212 
213 			commit = 1;
214 			continue;
215 		}
216 
217 		if (ap->dtad_kind == DTRACEACT_SPECULATE) {
218 			if (speculate) {
219 				dnerror(dnp, D_SPEC_SPEC, "speculate( ) may "
220 				    "not follow speculate( )\n");
221 			}
222 
223 			if (commit) {
224 				dnerror(dnp, D_SPEC_COMM, "speculate( ) may "
225 				    "not follow commit( )\n");
226 			}
227 
228 			if (datarec) {
229 				dnerror(dnp, D_SPEC_DREC, "speculate( ) may "
230 				    "not follow data-recording action(s)\n");
231 			}
232 
233 			speculate = 1;
234 			continue;
235 		}
236 
237 		if (DTRACEACT_ISAGG(ap->dtad_kind)) {
238 			if (speculate) {
239 				dnerror(dnp, D_AGG_SPEC, "aggregating actions "
240 				    "may not follow speculate( )\n");
241 			}
242 
243 			datarec = 1;
244 			continue;
245 		}
246 
247 		if (speculate) {
248 			if (dt_action_destructive(ap)) {
249 				dnerror(dnp, D_ACT_SPEC, "destructive actions "
250 				    "may not follow speculate( )\n");
251 			}
252 
253 			if (ap->dtad_kind == DTRACEACT_EXIT) {
254 				dnerror(dnp, D_EXIT_SPEC, "exit( ) may not "
255 				    "follow speculate( )\n");
256 			}
257 		}
258 
259 		/*
260 		 * Exclude all non data-recording actions.
261 		 */
262 		if (dt_action_destructive(ap) ||
263 		    ap->dtad_kind == DTRACEACT_DISCARD)
264 			continue;
265 
266 		if (ap->dtad_kind == DTRACEACT_DIFEXPR &&
267 		    ap->dtad_difo->dtdo_rtype.dtdt_kind == DIF_TYPE_CTF &&
268 		    ap->dtad_difo->dtdo_rtype.dtdt_size == 0)
269 			continue;
270 
271 		if (commit) {
272 			dnerror(dnp, D_DREC_COMM, "data-recording actions "
273 			    "may not follow commit( )\n");
274 		}
275 
276 		if (!speculate)
277 			datarec = 1;
278 	}
279 
280 	if (dtrace_stmt_add(yypcb->pcb_hdl, yypcb->pcb_prog, sdp) != 0)
281 		longjmp(yypcb->pcb_jmpbuf, dtrace_errno(yypcb->pcb_hdl));
282 
283 	if (yypcb->pcb_stmt == sdp)
284 		yypcb->pcb_stmt = NULL;
285 }
286 
287 /*
288  * For the first element of an aggregation tuple or for printa(), we create a
289  * simple DIF program that simply returns the immediate value that is the ID
290  * of the aggregation itself.  This could be optimized in the future by
291  * creating a new in-kernel dtad_kind that just returns an integer.
292  */
293 static void
294 dt_action_difconst(dtrace_actdesc_t *ap, uint_t id, dtrace_actkind_t kind)
295 {
296 	dtrace_hdl_t *dtp = yypcb->pcb_hdl;
297 	dtrace_difo_t *dp = dt_zalloc(dtp, sizeof (dtrace_difo_t));
298 
299 	if (dp == NULL)
300 		longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
301 
302 	dp->dtdo_buf = dt_alloc(dtp, sizeof (dif_instr_t) * 2);
303 	dp->dtdo_inttab = dt_alloc(dtp, sizeof (uint64_t));
304 
305 	if (dp->dtdo_buf == NULL || dp->dtdo_inttab == NULL) {
306 		dt_difo_free(dtp, dp);
307 		longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
308 	}
309 
310 	dp->dtdo_buf[0] = DIF_INSTR_SETX(0, 1); /* setx	DIF_INTEGER[0], %r1 */
311 	dp->dtdo_buf[1] = DIF_INSTR_RET(1);	/* ret	%r1 */
312 	dp->dtdo_len = 2;
313 	dp->dtdo_inttab[0] = id;
314 	dp->dtdo_intlen = 1;
315 	dp->dtdo_rtype = dt_int_rtype;
316 
317 	ap->dtad_difo = dp;
318 	ap->dtad_kind = kind;
319 }
320 
321 static void
322 dt_action_clear(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
323 {
324 	dt_ident_t *aid;
325 	dtrace_actdesc_t *ap;
326 	dt_node_t *anp;
327 
328 	char n[DT_TYPE_NAMELEN];
329 	int argc = 0;
330 
331 	for (anp = dnp->dn_args; anp != NULL; anp = anp->dn_list)
332 		argc++; /* count up arguments for error messages below */
333 
334 	if (argc != 1) {
335 		dnerror(dnp, D_CLEAR_PROTO,
336 		    "%s( ) prototype mismatch: %d args passed, 1 expected\n",
337 		    dnp->dn_ident->di_name, argc);
338 	}
339 
340 	anp = dnp->dn_args;
341 	assert(anp != NULL);
342 
343 	if (anp->dn_kind != DT_NODE_AGG) {
344 		dnerror(dnp, D_CLEAR_AGGARG,
345 		    "%s( ) argument #1 is incompatible with prototype:\n"
346 		    "\tprototype: aggregation\n\t argument: %s\n",
347 		    dnp->dn_ident->di_name,
348 		    dt_node_type_name(anp, n, sizeof (n)));
349 	}
350 
351 	aid = anp->dn_ident;
352 
353 	if (aid->di_gen == dtp->dt_gen && !(aid->di_flags & DT_IDFLG_MOD)) {
354 		dnerror(dnp, D_CLEAR_AGGBAD,
355 		    "undefined aggregation: @%s\n", aid->di_name);
356 	}
357 
358 	ap = dt_stmt_action(dtp, sdp);
359 	dt_action_difconst(ap, anp->dn_ident->di_id, DTRACEACT_LIBACT);
360 	ap->dtad_arg = DT_ACT_CLEAR;
361 }
362 
363 static void
364 dt_action_normalize(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
365 {
366 	dt_ident_t *aid;
367 	dtrace_actdesc_t *ap;
368 	dt_node_t *anp, *normal;
369 	int denormal = (strcmp(dnp->dn_ident->di_name, "denormalize") == 0);
370 
371 	char n[DT_TYPE_NAMELEN];
372 	int argc = 0;
373 
374 	for (anp = dnp->dn_args; anp != NULL; anp = anp->dn_list)
375 		argc++; /* count up arguments for error messages below */
376 
377 	if ((denormal && argc != 1) || (!denormal && argc != 2)) {
378 		dnerror(dnp, D_NORMALIZE_PROTO,
379 		    "%s( ) prototype mismatch: %d args passed, %d expected\n",
380 		    dnp->dn_ident->di_name, argc, denormal ? 1 : 2);
381 	}
382 
383 	anp = dnp->dn_args;
384 	assert(anp != NULL);
385 
386 	if (anp->dn_kind != DT_NODE_AGG) {
387 		dnerror(dnp, D_NORMALIZE_AGGARG,
388 		    "%s( ) argument #1 is incompatible with prototype:\n"
389 		    "\tprototype: aggregation\n\t argument: %s\n",
390 		    dnp->dn_ident->di_name,
391 		    dt_node_type_name(anp, n, sizeof (n)));
392 	}
393 
394 	if ((normal = anp->dn_list) != NULL && !dt_node_is_scalar(normal)) {
395 		dnerror(dnp, D_NORMALIZE_SCALAR,
396 		    "%s( ) argument #2 must be of scalar type\n",
397 		    dnp->dn_ident->di_name);
398 	}
399 
400 	aid = anp->dn_ident;
401 
402 	if (aid->di_gen == dtp->dt_gen && !(aid->di_flags & DT_IDFLG_MOD)) {
403 		dnerror(dnp, D_NORMALIZE_AGGBAD,
404 		    "undefined aggregation: @%s\n", aid->di_name);
405 	}
406 
407 	ap = dt_stmt_action(dtp, sdp);
408 	dt_action_difconst(ap, anp->dn_ident->di_id, DTRACEACT_LIBACT);
409 
410 	if (denormal) {
411 		ap->dtad_arg = DT_ACT_DENORMALIZE;
412 		return;
413 	}
414 
415 	ap->dtad_arg = DT_ACT_NORMALIZE;
416 
417 	assert(normal != NULL);
418 	ap = dt_stmt_action(dtp, sdp);
419 	dt_cg(yypcb, normal);
420 
421 	ap->dtad_difo = dt_as(yypcb);
422 	ap->dtad_kind = DTRACEACT_LIBACT;
423 	ap->dtad_arg = DT_ACT_NORMALIZE;
424 }
425 
426 static void
427 dt_action_trunc(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
428 {
429 	dt_ident_t *aid;
430 	dtrace_actdesc_t *ap;
431 	dt_node_t *anp, *trunc;
432 
433 	char n[DT_TYPE_NAMELEN];
434 	int argc = 0;
435 
436 	for (anp = dnp->dn_args; anp != NULL; anp = anp->dn_list)
437 		argc++; /* count up arguments for error messages below */
438 
439 	if (argc > 2 || argc < 1) {
440 		dnerror(dnp, D_TRUNC_PROTO,
441 		    "%s( ) prototype mismatch: %d args passed, %s expected\n",
442 		    dnp->dn_ident->di_name, argc,
443 		    argc < 1 ? "at least 1" : "no more than 2");
444 	}
445 
446 	anp = dnp->dn_args;
447 	assert(anp != NULL);
448 	trunc = anp->dn_list;
449 
450 	if (anp->dn_kind != DT_NODE_AGG) {
451 		dnerror(dnp, D_TRUNC_AGGARG,
452 		    "%s( ) argument #1 is incompatible with prototype:\n"
453 		    "\tprototype: aggregation\n\t argument: %s\n",
454 		    dnp->dn_ident->di_name,
455 		    dt_node_type_name(anp, n, sizeof (n)));
456 	}
457 
458 	if (argc == 2) {
459 		assert(trunc != NULL);
460 		if (!dt_node_is_scalar(trunc)) {
461 			dnerror(dnp, D_TRUNC_SCALAR,
462 			    "%s( ) argument #2 must be of scalar type\n",
463 			    dnp->dn_ident->di_name);
464 		}
465 	}
466 
467 	aid = anp->dn_ident;
468 
469 	if (aid->di_gen == dtp->dt_gen && !(aid->di_flags & DT_IDFLG_MOD)) {
470 		dnerror(dnp, D_TRUNC_AGGBAD,
471 		    "undefined aggregation: @%s\n", aid->di_name);
472 	}
473 
474 	ap = dt_stmt_action(dtp, sdp);
475 	dt_action_difconst(ap, anp->dn_ident->di_id, DTRACEACT_LIBACT);
476 	ap->dtad_arg = DT_ACT_TRUNC;
477 
478 	ap = dt_stmt_action(dtp, sdp);
479 
480 	if (argc == 1) {
481 		dt_action_difconst(ap, 0, DTRACEACT_LIBACT);
482 	} else {
483 		assert(trunc != NULL);
484 		dt_cg(yypcb, trunc);
485 		ap->dtad_difo = dt_as(yypcb);
486 		ap->dtad_kind = DTRACEACT_LIBACT;
487 	}
488 
489 	ap->dtad_arg = DT_ACT_TRUNC;
490 }
491 
492 static void
493 dt_action_printa(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
494 {
495 	dt_ident_t *aid, *fid;
496 	dtrace_actdesc_t *ap;
497 	const char *format;
498 	dt_node_t *anp, *proto = NULL;
499 
500 	char n[DT_TYPE_NAMELEN];
501 	int argc = 0, argr = 0;
502 
503 	for (anp = dnp->dn_args; anp != NULL; anp = anp->dn_list)
504 		argc++; /* count up arguments for error messages below */
505 
506 	switch (dnp->dn_args->dn_kind) {
507 	case DT_NODE_STRING:
508 		format = dnp->dn_args->dn_string;
509 		anp = dnp->dn_args->dn_list;
510 		argr = 2;
511 		break;
512 	case DT_NODE_AGG:
513 		format = NULL;
514 		anp = dnp->dn_args;
515 		argr = 1;
516 		break;
517 	default:
518 		format = NULL;
519 		anp = dnp->dn_args;
520 		argr = 1;
521 	}
522 
523 	if (argc < argr) {
524 		dnerror(dnp, D_PRINTA_PROTO,
525 		    "%s( ) prototype mismatch: %d args passed, %d expected\n",
526 		    dnp->dn_ident->di_name, argc, argr);
527 	}
528 
529 	assert(anp != NULL);
530 
531 	while (anp != NULL) {
532 		if (anp->dn_kind != DT_NODE_AGG) {
533 			dnerror(dnp, D_PRINTA_AGGARG,
534 			    "%s( ) argument #%d is incompatible with "
535 			    "prototype:\n\tprototype: aggregation\n"
536 			    "\t argument: %s\n", dnp->dn_ident->di_name, argr,
537 			    dt_node_type_name(anp, n, sizeof (n)));
538 		}
539 
540 		aid = anp->dn_ident;
541 		fid = aid->di_iarg;
542 
543 		if (aid->di_gen == dtp->dt_gen &&
544 		    !(aid->di_flags & DT_IDFLG_MOD)) {
545 			dnerror(dnp, D_PRINTA_AGGBAD,
546 			    "undefined aggregation: @%s\n", aid->di_name);
547 		}
548 
549 		/*
550 		 * If we have multiple aggregations, we must be sure that
551 		 * their key signatures match.
552 		 */
553 		if (proto != NULL) {
554 			dt_printa_validate(proto, anp);
555 		} else {
556 			proto = anp;
557 		}
558 
559 		if (format != NULL) {
560 			yylineno = dnp->dn_line;
561 
562 			sdp->dtsd_fmtdata =
563 			    dt_printf_create(yypcb->pcb_hdl, format);
564 			dt_printf_validate(sdp->dtsd_fmtdata,
565 			    DT_PRINTF_AGGREGATION, dnp->dn_ident, 1,
566 			    fid->di_id, ((dt_idsig_t *)aid->di_data)->dis_args);
567 			format = NULL;
568 		}
569 
570 		ap = dt_stmt_action(dtp, sdp);
571 		dt_action_difconst(ap, anp->dn_ident->di_id, DTRACEACT_PRINTA);
572 
573 		anp = anp->dn_list;
574 		argr++;
575 	}
576 }
577 
578 static void
579 dt_action_printflike(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp,
580     dtrace_actkind_t kind)
581 {
582 	dt_node_t *anp, *arg1;
583 	dtrace_actdesc_t *ap = NULL;
584 	char n[DT_TYPE_NAMELEN], *str;
585 
586 	assert(DTRACEACT_ISPRINTFLIKE(kind));
587 
588 	if (dnp->dn_args->dn_kind != DT_NODE_STRING) {
589 		dnerror(dnp, D_PRINTF_ARG_FMT,
590 		    "%s( ) argument #1 is incompatible with prototype:\n"
591 		    "\tprototype: string constant\n\t argument: %s\n",
592 		    dnp->dn_ident->di_name,
593 		    dt_node_type_name(dnp->dn_args, n, sizeof (n)));
594 	}
595 
596 	arg1 = dnp->dn_args->dn_list;
597 	yylineno = dnp->dn_line;
598 	str = dnp->dn_args->dn_string;
599 
600 
601 	/*
602 	 * If this is an freopen(), we use an empty string to denote that
603 	 * stdout should be restored.  For other printf()-like actions, an
604 	 * empty format string is illegal:  an empty format string would
605 	 * result in malformed DOF, and the compiler thus flags an empty
606 	 * format string as a compile-time error.  To avoid propagating the
607 	 * freopen() special case throughout the system, we simply transpose
608 	 * an empty string into a sentinel string (DT_FREOPEN_RESTORE) that
609 	 * denotes that stdout should be restored.
610 	 */
611 	if (kind == DTRACEACT_FREOPEN) {
612 		if (strcmp(str, DT_FREOPEN_RESTORE) == 0) {
613 			/*
614 			 * Our sentinel is always an invalid argument to
615 			 * freopen(), but if it's been manually specified, we
616 			 * must fail now instead of when the freopen() is
617 			 * actually evaluated.
618 			 */
619 			dnerror(dnp, D_FREOPEN_INVALID,
620 			    "%s( ) argument #1 cannot be \"%s\"\n",
621 			    dnp->dn_ident->di_name, DT_FREOPEN_RESTORE);
622 		}
623 
624 		if (str[0] == '\0')
625 			str = DT_FREOPEN_RESTORE;
626 	}
627 
628 	sdp->dtsd_fmtdata = dt_printf_create(dtp, str);
629 
630 	dt_printf_validate(sdp->dtsd_fmtdata, DT_PRINTF_EXACTLEN,
631 	    dnp->dn_ident, 1, DTRACEACT_AGGREGATION, arg1);
632 
633 	if (arg1 == NULL) {
634 		dif_instr_t *dbuf;
635 		dtrace_difo_t *dp;
636 
637 		if ((dbuf = dt_alloc(dtp, sizeof (dif_instr_t))) == NULL ||
638 		    (dp = dt_zalloc(dtp, sizeof (dtrace_difo_t))) == NULL) {
639 			dt_free(dtp, dbuf);
640 			longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
641 		}
642 
643 		dbuf[0] = DIF_INSTR_RET(DIF_REG_R0); /* ret %r0 */
644 
645 		dp->dtdo_buf = dbuf;
646 		dp->dtdo_len = 1;
647 		dp->dtdo_rtype = dt_int_rtype;
648 
649 		ap = dt_stmt_action(dtp, sdp);
650 		ap->dtad_difo = dp;
651 		ap->dtad_kind = kind;
652 		return;
653 	}
654 
655 	for (anp = arg1; anp != NULL; anp = anp->dn_list) {
656 		ap = dt_stmt_action(dtp, sdp);
657 		dt_cg(yypcb, anp);
658 		ap->dtad_difo = dt_as(yypcb);
659 		ap->dtad_kind = kind;
660 	}
661 }
662 
663 static void
664 dt_action_trace(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
665 {
666 	int ctflib;
667 
668 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
669 	boolean_t istrace = (dnp->dn_ident->di_id == DT_ACT_TRACE);
670 	const char *act = istrace ?  "trace" : "print";
671 
672 	if (dt_node_is_void(dnp->dn_args)) {
673 		dnerror(dnp->dn_args, istrace ? D_TRACE_VOID : D_PRINT_VOID,
674 		    "%s( ) may not be applied to a void expression\n", act);
675 	}
676 
677 	if (dt_node_resolve(dnp->dn_args, DT_IDENT_XLPTR) != NULL) {
678 		dnerror(dnp->dn_args, istrace ? D_TRACE_DYN : D_PRINT_DYN,
679 		    "%s( ) may not be applied to a translated pointer\n", act);
680 	}
681 
682 	if (dnp->dn_args->dn_kind == DT_NODE_AGG) {
683 		dnerror(dnp->dn_args, istrace ? D_TRACE_AGG : D_PRINT_AGG,
684 		    "%s( ) may not be applied to an aggregation%s\n", act,
685 		    istrace ? "" : " -- did you mean printa()?");
686 	}
687 
688 	dt_cg(yypcb, dnp->dn_args);
689 
690 	/*
691 	 * The print() action behaves identically to trace(), except that it
692 	 * stores the CTF type of the argument (if present) within the DOF for
693 	 * the DIFEXPR action.  To do this, we set the 'dtsd_strdata' to point
694 	 * to the fully-qualified CTF type ID for the result of the DIF
695 	 * action.  We use the ID instead of the name to handles complex types
696 	 * like arrays and function pointers that can't be resolved by
697 	 * ctf_type_lookup().  This is later processed by dtrace_dof_create()
698 	 * and turned into a reference into the string table so that we can
699 	 * get the type information when we process the data after the fact.  In
700 	 * the case where we are referring to userland CTF data, we also need to
701 	 * to identify which ctf container in question we care about and encode
702 	 * that within the name.
703 	 */
704 	if (dnp->dn_ident->di_id == DT_ACT_PRINT) {
705 		dt_node_t *dret;
706 		size_t n;
707 		dt_module_t *dmp;
708 
709 		dret = yypcb->pcb_dret;
710 		dmp = dt_module_lookup_by_ctf(dtp, dret->dn_ctfp);
711 
712 		n = snprintf(NULL, 0, "%s`%ld", dmp->dm_name, dret->dn_type) + 1;
713 		if (dmp->dm_pid != 0) {
714 			ctflib = dt_module_getlibid(dtp, dmp, dret->dn_ctfp);
715 			assert(ctflib >= 0);
716 			n = snprintf(NULL, 0, "%s`%d`%ld", dmp->dm_name,
717 			    ctflib, dret->dn_type) + 1;
718 		} else {
719 			n = snprintf(NULL, 0, "%s`%ld", dmp->dm_name,
720 			    dret->dn_type) + 1;
721 		}
722 		sdp->dtsd_strdata = dt_alloc(dtp, n);
723 		if (sdp->dtsd_strdata == NULL)
724 			longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
725 		(void) snprintf(sdp->dtsd_strdata, n, "%s`%ld", dmp->dm_name,
726 		    dret->dn_type);
727 		if (dmp->dm_pid != 0) {
728 			(void) snprintf(sdp->dtsd_strdata, n, "%s`%d`%ld",
729 			    dmp->dm_name, ctflib, dret->dn_type);
730 		} else {
731 			(void) snprintf(sdp->dtsd_strdata, n, "%s`%ld",
732 			    dmp->dm_name, dret->dn_type);
733 		}
734 	}
735 
736 	ap->dtad_difo = dt_as(yypcb);
737 	ap->dtad_kind = DTRACEACT_DIFEXPR;
738 }
739 
740 static void
741 dt_action_tracemem(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
742 {
743 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
744 
745 	dt_node_t *addr = dnp->dn_args;
746 	dt_node_t *max = dnp->dn_args->dn_list;
747 	dt_node_t *size;
748 
749 	char n[DT_TYPE_NAMELEN];
750 
751 	if (dt_node_is_integer(addr) == 0 && dt_node_is_pointer(addr) == 0) {
752 		dnerror(addr, D_TRACEMEM_ADDR,
753 		    "tracemem( ) argument #1 is incompatible with "
754 		    "prototype:\n\tprototype: pointer or integer\n"
755 		    "\t argument: %s\n",
756 		    dt_node_type_name(addr, n, sizeof (n)));
757 	}
758 
759 	if (dt_node_is_posconst(max) == 0) {
760 		dnerror(max, D_TRACEMEM_SIZE, "tracemem( ) argument #2 must "
761 		    "be a non-zero positive integral constant expression\n");
762 	}
763 
764 	if ((size = max->dn_list) != NULL) {
765 		if (size->dn_list != NULL) {
766 			dnerror(size, D_TRACEMEM_ARGS, "tracemem ( ) prototype "
767 			    "mismatch: expected at most 3 args\n");
768 		}
769 
770 		if (!dt_node_is_scalar(size)) {
771 			dnerror(size, D_TRACEMEM_DYNSIZE, "tracemem ( ) "
772 			    "dynamic size (argument #3) must be of "
773 			    "scalar type\n");
774 		}
775 
776 		dt_cg(yypcb, size);
777 		ap->dtad_difo = dt_as(yypcb);
778 		ap->dtad_difo->dtdo_rtype = dt_int_rtype;
779 		ap->dtad_kind = DTRACEACT_TRACEMEM_DYNSIZE;
780 
781 		ap = dt_stmt_action(dtp, sdp);
782 	}
783 
784 	dt_cg(yypcb, addr);
785 	ap->dtad_difo = dt_as(yypcb);
786 	ap->dtad_kind = DTRACEACT_TRACEMEM;
787 
788 	ap->dtad_difo->dtdo_rtype.dtdt_flags |= DIF_TF_BYREF;
789 	ap->dtad_difo->dtdo_rtype.dtdt_size = max->dn_value;
790 }
791 
792 static void
793 dt_action_stack_args(dtrace_hdl_t *dtp, dtrace_actdesc_t *ap, dt_node_t *arg0)
794 {
795 	ap->dtad_kind = DTRACEACT_STACK;
796 
797 	if (dtp->dt_options[DTRACEOPT_STACKFRAMES] != DTRACEOPT_UNSET) {
798 		ap->dtad_arg = dtp->dt_options[DTRACEOPT_STACKFRAMES];
799 	} else {
800 		ap->dtad_arg = 0;
801 	}
802 
803 	if (arg0 != NULL) {
804 		if (arg0->dn_list != NULL) {
805 			dnerror(arg0, D_STACK_PROTO, "stack( ) prototype "
806 			    "mismatch: too many arguments\n");
807 		}
808 
809 		if (dt_node_is_posconst(arg0) == 0) {
810 			dnerror(arg0, D_STACK_SIZE, "stack( ) size must be a "
811 			    "non-zero positive integral constant expression\n");
812 		}
813 
814 		ap->dtad_arg = arg0->dn_value;
815 	}
816 }
817 
818 static void
819 dt_action_stack(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
820 {
821 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
822 	dt_action_stack_args(dtp, ap, dnp->dn_args);
823 }
824 
825 static void
826 dt_action_ustack_args(dtrace_hdl_t *dtp, dtrace_actdesc_t *ap, dt_node_t *dnp)
827 {
828 	uint32_t nframes = 0;
829 	uint32_t strsize = 0;	/* default string table size */
830 	dt_node_t *arg0 = dnp->dn_args;
831 	dt_node_t *arg1 = arg0 != NULL ? arg0->dn_list : NULL;
832 
833 	assert(dnp->dn_ident->di_id == DT_ACT_JSTACK ||
834 	    dnp->dn_ident->di_id == DT_ACT_USTACK);
835 
836 	if (dnp->dn_ident->di_id == DT_ACT_JSTACK) {
837 		if (dtp->dt_options[DTRACEOPT_JSTACKFRAMES] != DTRACEOPT_UNSET)
838 			nframes = dtp->dt_options[DTRACEOPT_JSTACKFRAMES];
839 
840 		if (dtp->dt_options[DTRACEOPT_JSTACKSTRSIZE] != DTRACEOPT_UNSET)
841 			strsize = dtp->dt_options[DTRACEOPT_JSTACKSTRSIZE];
842 
843 		ap->dtad_kind = DTRACEACT_JSTACK;
844 	} else {
845 		assert(dnp->dn_ident->di_id == DT_ACT_USTACK);
846 
847 		if (dtp->dt_options[DTRACEOPT_USTACKFRAMES] != DTRACEOPT_UNSET)
848 			nframes = dtp->dt_options[DTRACEOPT_USTACKFRAMES];
849 
850 		ap->dtad_kind = DTRACEACT_USTACK;
851 	}
852 
853 	if (arg0 != NULL) {
854 		if (!dt_node_is_posconst(arg0)) {
855 			dnerror(arg0, D_USTACK_FRAMES, "ustack( ) argument #1 "
856 			    "must be a non-zero positive integer constant\n");
857 		}
858 		nframes = (uint32_t)arg0->dn_value;
859 	}
860 
861 	if (arg1 != NULL) {
862 		if (arg1->dn_kind != DT_NODE_INT ||
863 		    ((arg1->dn_flags & DT_NF_SIGNED) &&
864 		    (int64_t)arg1->dn_value < 0)) {
865 			dnerror(arg1, D_USTACK_STRSIZE, "ustack( ) argument #2 "
866 			    "must be a positive integer constant\n");
867 		}
868 
869 		if (arg1->dn_list != NULL) {
870 			dnerror(arg1, D_USTACK_PROTO, "ustack( ) prototype "
871 			    "mismatch: too many arguments\n");
872 		}
873 
874 		strsize = (uint32_t)arg1->dn_value;
875 	}
876 
877 	ap->dtad_arg = DTRACE_USTACK_ARG(nframes, strsize);
878 }
879 
880 static void
881 dt_action_ustack(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
882 {
883 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
884 	dt_action_ustack_args(dtp, ap, dnp);
885 }
886 
887 static void
888 dt_action_setopt(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
889 {
890 	dtrace_actdesc_t *ap;
891 	dt_node_t *arg0, *arg1;
892 
893 	/*
894 	 * The prototype guarantees that we are called with either one or
895 	 * two arguments, and that any arguments that are present are strings.
896 	 */
897 	arg0 = dnp->dn_args;
898 	arg1 = arg0->dn_list;
899 
900 	ap = dt_stmt_action(dtp, sdp);
901 	dt_cg(yypcb, arg0);
902 	ap->dtad_difo = dt_as(yypcb);
903 	ap->dtad_kind = DTRACEACT_LIBACT;
904 	ap->dtad_arg = DT_ACT_SETOPT;
905 
906 	ap = dt_stmt_action(dtp, sdp);
907 
908 	if (arg1 == NULL) {
909 		dt_action_difconst(ap, 0, DTRACEACT_LIBACT);
910 	} else {
911 		dt_cg(yypcb, arg1);
912 		ap->dtad_difo = dt_as(yypcb);
913 		ap->dtad_kind = DTRACEACT_LIBACT;
914 	}
915 
916 	ap->dtad_arg = DT_ACT_SETOPT;
917 }
918 
919 /*ARGSUSED*/
920 static void
921 dt_action_symmod_args(dtrace_hdl_t *dtp, dtrace_actdesc_t *ap,
922     dt_node_t *dnp, dtrace_actkind_t kind)
923 {
924 	assert(kind == DTRACEACT_SYM || kind == DTRACEACT_MOD ||
925 	    kind == DTRACEACT_USYM || kind == DTRACEACT_UMOD ||
926 	    kind == DTRACEACT_UADDR);
927 
928 	dt_cg(yypcb, dnp);
929 	ap->dtad_difo = dt_as(yypcb);
930 	ap->dtad_kind = kind;
931 	ap->dtad_difo->dtdo_rtype.dtdt_size = sizeof (uint64_t);
932 }
933 
934 static void
935 dt_action_symmod(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp,
936     dtrace_actkind_t kind)
937 {
938 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
939 	dt_action_symmod_args(dtp, ap, dnp->dn_args, kind);
940 }
941 
942 /*ARGSUSED*/
943 static void
944 dt_action_ftruncate(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
945 {
946 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
947 
948 	/*
949 	 * Library actions need a DIFO that serves as an argument.  As
950 	 * ftruncate() doesn't take an argument, we generate the constant 0
951 	 * in a DIFO; this constant will be ignored when the ftruncate() is
952 	 * processed.
953 	 */
954 	dt_action_difconst(ap, 0, DTRACEACT_LIBACT);
955 	ap->dtad_arg = DT_ACT_FTRUNCATE;
956 }
957 
958 /*ARGSUSED*/
959 static void
960 dt_action_stop(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
961 {
962 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
963 
964 	ap->dtad_kind = DTRACEACT_STOP;
965 	ap->dtad_arg = 0;
966 }
967 
968 /*ARGSUSED*/
969 static void
970 dt_action_breakpoint(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
971 {
972 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
973 
974 	ap->dtad_kind = DTRACEACT_BREAKPOINT;
975 	ap->dtad_arg = 0;
976 }
977 
978 /*ARGSUSED*/
979 static void
980 dt_action_panic(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
981 {
982 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
983 
984 	ap->dtad_kind = DTRACEACT_PANIC;
985 	ap->dtad_arg = 0;
986 }
987 
988 static void
989 dt_action_chill(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
990 {
991 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
992 
993 	dt_cg(yypcb, dnp->dn_args);
994 	ap->dtad_difo = dt_as(yypcb);
995 	ap->dtad_kind = DTRACEACT_CHILL;
996 }
997 
998 static void
999 dt_action_raise(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
1000 {
1001 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
1002 
1003 	dt_cg(yypcb, dnp->dn_args);
1004 	ap->dtad_difo = dt_as(yypcb);
1005 	ap->dtad_kind = DTRACEACT_RAISE;
1006 }
1007 
1008 static void
1009 dt_action_exit(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
1010 {
1011 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
1012 
1013 	dt_cg(yypcb, dnp->dn_args);
1014 	ap->dtad_difo = dt_as(yypcb);
1015 	ap->dtad_kind = DTRACEACT_EXIT;
1016 	ap->dtad_difo->dtdo_rtype.dtdt_size = sizeof (int);
1017 }
1018 
1019 static void
1020 dt_action_speculate(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
1021 {
1022 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
1023 
1024 	dt_cg(yypcb, dnp->dn_args);
1025 	ap->dtad_difo = dt_as(yypcb);
1026 	ap->dtad_kind = DTRACEACT_SPECULATE;
1027 }
1028 
1029 static void
1030 dt_action_printm(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
1031 {
1032 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
1033 
1034 	dt_node_t *size = dnp->dn_args;
1035 	dt_node_t *addr = dnp->dn_args->dn_list;
1036 
1037 	char n[DT_TYPE_NAMELEN];
1038 
1039 	if (dt_node_is_posconst(size) == 0) {
1040 		dnerror(size, D_PRINTM_SIZE, "printm( ) argument #1 must "
1041 		    "be a non-zero positive integral constant expression\n");
1042 	}
1043 
1044 	if (dt_node_is_pointer(addr) == 0) {
1045 		dnerror(addr, D_PRINTM_ADDR,
1046 		    "printm( ) argument #2 is incompatible with "
1047 		    "prototype:\n\tprototype: pointer\n"
1048 		    "\t argument: %s\n",
1049 		    dt_node_type_name(addr, n, sizeof (n)));
1050 	}
1051 
1052 	dt_cg(yypcb, addr);
1053 	ap->dtad_difo = dt_as(yypcb);
1054 	ap->dtad_kind = DTRACEACT_PRINTM;
1055 
1056 	ap->dtad_difo->dtdo_rtype.dtdt_flags |= DIF_TF_BYREF;
1057 	ap->dtad_difo->dtdo_rtype.dtdt_size = size->dn_value + sizeof(uintptr_t);
1058 }
1059 
1060 static void
1061 dt_action_commit(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
1062 {
1063 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
1064 
1065 	dt_cg(yypcb, dnp->dn_args);
1066 	ap->dtad_difo = dt_as(yypcb);
1067 	ap->dtad_kind = DTRACEACT_COMMIT;
1068 }
1069 
1070 static void
1071 dt_action_discard(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
1072 {
1073 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
1074 
1075 	dt_cg(yypcb, dnp->dn_args);
1076 	ap->dtad_difo = dt_as(yypcb);
1077 	ap->dtad_kind = DTRACEACT_DISCARD;
1078 }
1079 
1080 static void
1081 dt_compile_fun(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
1082 {
1083 	switch (dnp->dn_expr->dn_ident->di_id) {
1084 	case DT_ACT_BREAKPOINT:
1085 		dt_action_breakpoint(dtp, dnp->dn_expr, sdp);
1086 		break;
1087 	case DT_ACT_CHILL:
1088 		dt_action_chill(dtp, dnp->dn_expr, sdp);
1089 		break;
1090 	case DT_ACT_CLEAR:
1091 		dt_action_clear(dtp, dnp->dn_expr, sdp);
1092 		break;
1093 	case DT_ACT_COMMIT:
1094 		dt_action_commit(dtp, dnp->dn_expr, sdp);
1095 		break;
1096 	case DT_ACT_DENORMALIZE:
1097 		dt_action_normalize(dtp, dnp->dn_expr, sdp);
1098 		break;
1099 	case DT_ACT_DISCARD:
1100 		dt_action_discard(dtp, dnp->dn_expr, sdp);
1101 		break;
1102 	case DT_ACT_EXIT:
1103 		dt_action_exit(dtp, dnp->dn_expr, sdp);
1104 		break;
1105 	case DT_ACT_FREOPEN:
1106 		dt_action_printflike(dtp, dnp->dn_expr, sdp, DTRACEACT_FREOPEN);
1107 		break;
1108 	case DT_ACT_FTRUNCATE:
1109 		dt_action_ftruncate(dtp, dnp->dn_expr, sdp);
1110 		break;
1111 	case DT_ACT_MOD:
1112 		dt_action_symmod(dtp, dnp->dn_expr, sdp, DTRACEACT_MOD);
1113 		break;
1114 	case DT_ACT_NORMALIZE:
1115 		dt_action_normalize(dtp, dnp->dn_expr, sdp);
1116 		break;
1117 	case DT_ACT_PANIC:
1118 		dt_action_panic(dtp, dnp->dn_expr, sdp);
1119 		break;
1120 	case DT_ACT_PRINT:
1121 		dt_action_trace(dtp, dnp->dn_expr, sdp);
1122 		break;
1123 	case DT_ACT_PRINTA:
1124 		dt_action_printa(dtp, dnp->dn_expr, sdp);
1125 		break;
1126 	case DT_ACT_PRINTF:
1127 		dt_action_printflike(dtp, dnp->dn_expr, sdp, DTRACEACT_PRINTF);
1128 		break;
1129 	case DT_ACT_PRINTM:
1130 		dt_action_printm(dtp, dnp->dn_expr, sdp);
1131 		break;
1132 	case DT_ACT_RAISE:
1133 		dt_action_raise(dtp, dnp->dn_expr, sdp);
1134 		break;
1135 	case DT_ACT_SETOPT:
1136 		dt_action_setopt(dtp, dnp->dn_expr, sdp);
1137 		break;
1138 	case DT_ACT_SPECULATE:
1139 		dt_action_speculate(dtp, dnp->dn_expr, sdp);
1140 		break;
1141 	case DT_ACT_STACK:
1142 		dt_action_stack(dtp, dnp->dn_expr, sdp);
1143 		break;
1144 	case DT_ACT_STOP:
1145 		dt_action_stop(dtp, dnp->dn_expr, sdp);
1146 		break;
1147 	case DT_ACT_SYM:
1148 		dt_action_symmod(dtp, dnp->dn_expr, sdp, DTRACEACT_SYM);
1149 		break;
1150 	case DT_ACT_SYSTEM:
1151 		dt_action_printflike(dtp, dnp->dn_expr, sdp, DTRACEACT_SYSTEM);
1152 		break;
1153 	case DT_ACT_TRACE:
1154 		dt_action_trace(dtp, dnp->dn_expr, sdp);
1155 		break;
1156 	case DT_ACT_TRACEMEM:
1157 		dt_action_tracemem(dtp, dnp->dn_expr, sdp);
1158 		break;
1159 	case DT_ACT_TRUNC:
1160 		dt_action_trunc(dtp, dnp->dn_expr, sdp);
1161 		break;
1162 	case DT_ACT_UADDR:
1163 		dt_action_symmod(dtp, dnp->dn_expr, sdp, DTRACEACT_UADDR);
1164 		break;
1165 	case DT_ACT_UMOD:
1166 		dt_action_symmod(dtp, dnp->dn_expr, sdp, DTRACEACT_UMOD);
1167 		break;
1168 	case DT_ACT_USYM:
1169 		dt_action_symmod(dtp, dnp->dn_expr, sdp, DTRACEACT_USYM);
1170 		break;
1171 	case DT_ACT_USTACK:
1172 	case DT_ACT_JSTACK:
1173 		dt_action_ustack(dtp, dnp->dn_expr, sdp);
1174 		break;
1175 	default:
1176 		dnerror(dnp->dn_expr, D_UNKNOWN, "tracing function %s( ) is "
1177 		    "not yet supported\n", dnp->dn_expr->dn_ident->di_name);
1178 	}
1179 }
1180 
1181 static void
1182 dt_compile_exp(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
1183 {
1184 	dtrace_actdesc_t *ap = dt_stmt_action(dtp, sdp);
1185 
1186 	dt_cg(yypcb, dnp->dn_expr);
1187 	ap->dtad_difo = dt_as(yypcb);
1188 	ap->dtad_difo->dtdo_rtype = dt_void_rtype;
1189 	ap->dtad_kind = DTRACEACT_DIFEXPR;
1190 }
1191 
1192 static void
1193 dt_compile_agg(dtrace_hdl_t *dtp, dt_node_t *dnp, dtrace_stmtdesc_t *sdp)
1194 {
1195 	dt_ident_t *aid, *fid;
1196 	dt_node_t *anp, *incr = NULL;
1197 	dtrace_actdesc_t *ap;
1198 	uint_t n = 1, argmax;
1199 	uint64_t arg = 0;
1200 
1201 	/*
1202 	 * If the aggregation has no aggregating function applied to it, then
1203 	 * this statement has no effect.  Flag this as a programming error.
1204 	 */
1205 	if (dnp->dn_aggfun == NULL) {
1206 		dnerror(dnp, D_AGG_NULL, "expression has null effect: @%s\n",
1207 		    dnp->dn_ident->di_name);
1208 	}
1209 
1210 	aid = dnp->dn_ident;
1211 	fid = dnp->dn_aggfun->dn_ident;
1212 
1213 	if (dnp->dn_aggfun->dn_args != NULL &&
1214 	    dt_node_is_scalar(dnp->dn_aggfun->dn_args) == 0) {
1215 		dnerror(dnp->dn_aggfun, D_AGG_SCALAR, "%s( ) argument #1 must "
1216 		    "be of scalar type\n", fid->di_name);
1217 	}
1218 
1219 	/*
1220 	 * The ID of the aggregation itself is implicitly recorded as the first
1221 	 * member of each aggregation tuple so we can distinguish them later.
1222 	 */
1223 	ap = dt_stmt_action(dtp, sdp);
1224 	dt_action_difconst(ap, aid->di_id, DTRACEACT_DIFEXPR);
1225 
1226 	for (anp = dnp->dn_aggtup; anp != NULL; anp = anp->dn_list) {
1227 		ap = dt_stmt_action(dtp, sdp);
1228 		n++;
1229 
1230 		if (anp->dn_kind == DT_NODE_FUNC) {
1231 			if (anp->dn_ident->di_id == DT_ACT_STACK) {
1232 				dt_action_stack_args(dtp, ap, anp->dn_args);
1233 				continue;
1234 			}
1235 
1236 			if (anp->dn_ident->di_id == DT_ACT_USTACK ||
1237 			    anp->dn_ident->di_id == DT_ACT_JSTACK) {
1238 				dt_action_ustack_args(dtp, ap, anp);
1239 				continue;
1240 			}
1241 
1242 			switch (anp->dn_ident->di_id) {
1243 			case DT_ACT_UADDR:
1244 				dt_action_symmod_args(dtp, ap,
1245 				    anp->dn_args, DTRACEACT_UADDR);
1246 				continue;
1247 
1248 			case DT_ACT_USYM:
1249 				dt_action_symmod_args(dtp, ap,
1250 				    anp->dn_args, DTRACEACT_USYM);
1251 				continue;
1252 
1253 			case DT_ACT_UMOD:
1254 				dt_action_symmod_args(dtp, ap,
1255 				    anp->dn_args, DTRACEACT_UMOD);
1256 				continue;
1257 
1258 			case DT_ACT_SYM:
1259 				dt_action_symmod_args(dtp, ap,
1260 				    anp->dn_args, DTRACEACT_SYM);
1261 				continue;
1262 
1263 			case DT_ACT_MOD:
1264 				dt_action_symmod_args(dtp, ap,
1265 				    anp->dn_args, DTRACEACT_MOD);
1266 				continue;
1267 
1268 			default:
1269 				break;
1270 			}
1271 		}
1272 
1273 		dt_cg(yypcb, anp);
1274 		ap->dtad_difo = dt_as(yypcb);
1275 		ap->dtad_kind = DTRACEACT_DIFEXPR;
1276 	}
1277 
1278 	if (fid->di_id == DTRACEAGG_LQUANTIZE) {
1279 		/*
1280 		 * For linear quantization, we have between two and four
1281 		 * arguments in addition to the expression:
1282 		 *
1283 		 *    arg1 => Base value
1284 		 *    arg2 => Limit value
1285 		 *    arg3 => Quantization level step size (defaults to 1)
1286 		 *    arg4 => Quantization increment value (defaults to 1)
1287 		 */
1288 		dt_node_t *arg1 = dnp->dn_aggfun->dn_args->dn_list;
1289 		dt_node_t *arg2 = arg1->dn_list;
1290 		dt_node_t *arg3 = arg2->dn_list;
1291 		dt_idsig_t *isp;
1292 		uint64_t nlevels, step = 1, oarg;
1293 		int64_t baseval, limitval;
1294 
1295 		if (arg1->dn_kind != DT_NODE_INT) {
1296 			dnerror(arg1, D_LQUANT_BASETYPE, "lquantize( ) "
1297 			    "argument #1 must be an integer constant\n");
1298 		}
1299 
1300 		baseval = (int64_t)arg1->dn_value;
1301 
1302 		if (baseval < INT32_MIN || baseval > INT32_MAX) {
1303 			dnerror(arg1, D_LQUANT_BASEVAL, "lquantize( ) "
1304 			    "argument #1 must be a 32-bit quantity\n");
1305 		}
1306 
1307 		if (arg2->dn_kind != DT_NODE_INT) {
1308 			dnerror(arg2, D_LQUANT_LIMTYPE, "lquantize( ) "
1309 			    "argument #2 must be an integer constant\n");
1310 		}
1311 
1312 		limitval = (int64_t)arg2->dn_value;
1313 
1314 		if (limitval < INT32_MIN || limitval > INT32_MAX) {
1315 			dnerror(arg2, D_LQUANT_LIMVAL, "lquantize( ) "
1316 			    "argument #2 must be a 32-bit quantity\n");
1317 		}
1318 
1319 		if (limitval < baseval) {
1320 			dnerror(dnp, D_LQUANT_MISMATCH,
1321 			    "lquantize( ) base (argument #1) must be less "
1322 			    "than limit (argument #2)\n");
1323 		}
1324 
1325 		if (arg3 != NULL) {
1326 			if (!dt_node_is_posconst(arg3)) {
1327 				dnerror(arg3, D_LQUANT_STEPTYPE, "lquantize( ) "
1328 				    "argument #3 must be a non-zero positive "
1329 				    "integer constant\n");
1330 			}
1331 
1332 			if ((step = arg3->dn_value) > UINT16_MAX) {
1333 				dnerror(arg3, D_LQUANT_STEPVAL, "lquantize( ) "
1334 				    "argument #3 must be a 16-bit quantity\n");
1335 			}
1336 		}
1337 
1338 		nlevels = (limitval - baseval) / step;
1339 
1340 		if (nlevels == 0) {
1341 			dnerror(dnp, D_LQUANT_STEPLARGE,
1342 			    "lquantize( ) step (argument #3) too large: must "
1343 			    "have at least one quantization level\n");
1344 		}
1345 
1346 		if (nlevels > UINT16_MAX) {
1347 			dnerror(dnp, D_LQUANT_STEPSMALL, "lquantize( ) step "
1348 			    "(argument #3) too small: number of quantization "
1349 			    "levels must be a 16-bit quantity\n");
1350 		}
1351 
1352 		arg = (step << DTRACE_LQUANTIZE_STEPSHIFT) |
1353 		    (nlevels << DTRACE_LQUANTIZE_LEVELSHIFT) |
1354 		    ((baseval << DTRACE_LQUANTIZE_BASESHIFT) &
1355 		    DTRACE_LQUANTIZE_BASEMASK);
1356 
1357 		assert(arg != 0);
1358 
1359 		isp = (dt_idsig_t *)aid->di_data;
1360 
1361 		if (isp->dis_auxinfo == 0) {
1362 			/*
1363 			 * This is the first time we've seen an lquantize()
1364 			 * for this aggregation; we'll store our argument
1365 			 * as the auxiliary signature information.
1366 			 */
1367 			isp->dis_auxinfo = arg;
1368 		} else if ((oarg = isp->dis_auxinfo) != arg) {
1369 			/*
1370 			 * If we have seen this lquantize() before and the
1371 			 * argument doesn't match the original argument, pick
1372 			 * the original argument apart to concisely report the
1373 			 * mismatch.
1374 			 */
1375 			int obaseval = DTRACE_LQUANTIZE_BASE(oarg);
1376 			int onlevels = DTRACE_LQUANTIZE_LEVELS(oarg);
1377 			int ostep = DTRACE_LQUANTIZE_STEP(oarg);
1378 
1379 			if (obaseval != baseval) {
1380 				dnerror(dnp, D_LQUANT_MATCHBASE, "lquantize( ) "
1381 				    "base (argument #1) doesn't match previous "
1382 				    "declaration: expected %d, found %d\n",
1383 				    obaseval, (int)baseval);
1384 			}
1385 
1386 			if (onlevels * ostep != nlevels * step) {
1387 				dnerror(dnp, D_LQUANT_MATCHLIM, "lquantize( ) "
1388 				    "limit (argument #2) doesn't match previous"
1389 				    " declaration: expected %d, found %d\n",
1390 				    obaseval + onlevels * ostep,
1391 				    (int)baseval + (int)nlevels * (int)step);
1392 			}
1393 
1394 			if (ostep != step) {
1395 				dnerror(dnp, D_LQUANT_MATCHSTEP, "lquantize( ) "
1396 				    "step (argument #3) doesn't match previous "
1397 				    "declaration: expected %d, found %d\n",
1398 				    ostep, (int)step);
1399 			}
1400 
1401 			/*
1402 			 * We shouldn't be able to get here -- one of the
1403 			 * parameters must be mismatched if the arguments
1404 			 * didn't match.
1405 			 */
1406 			assert(0);
1407 		}
1408 
1409 		incr = arg3 != NULL ? arg3->dn_list : NULL;
1410 		argmax = 5;
1411 	}
1412 
1413 	if (fid->di_id == DTRACEAGG_LLQUANTIZE) {
1414 		/*
1415 		 * For log/linear quantizations, we have between one and five
1416 		 * arguments in addition to the expression:
1417 		 *
1418 		 *    arg1 => Factor
1419 		 *    arg2 => Low magnitude
1420 		 *    arg3 => High magnitude
1421 		 *    arg4 => Number of steps per magnitude
1422 		 *    arg5 => Quantization increment value (defaults to 1)
1423 		 */
1424 		dt_node_t *llarg = dnp->dn_aggfun->dn_args->dn_list;
1425 		uint64_t oarg, order, v;
1426 		dt_idsig_t *isp;
1427 		int i;
1428 
1429 		struct {
1430 			char *str;		/* string identifier */
1431 			int badtype;		/* error on bad type */
1432 			int badval;		/* error on bad value */
1433 			int mismatch;		/* error on bad match */
1434 			int shift;		/* shift value */
1435 			uint16_t value;		/* value itself */
1436 		} args[] = {
1437 			{ "factor", D_LLQUANT_FACTORTYPE,
1438 			    D_LLQUANT_FACTORVAL, D_LLQUANT_FACTORMATCH,
1439 			    DTRACE_LLQUANTIZE_FACTORSHIFT },
1440 			{ "low magnitude", D_LLQUANT_LOWTYPE,
1441 			    D_LLQUANT_LOWVAL, D_LLQUANT_LOWMATCH,
1442 			    DTRACE_LLQUANTIZE_LOWSHIFT },
1443 			{ "high magnitude", D_LLQUANT_HIGHTYPE,
1444 			    D_LLQUANT_HIGHVAL, D_LLQUANT_HIGHMATCH,
1445 			    DTRACE_LLQUANTIZE_HIGHSHIFT },
1446 			{ "linear steps per magnitude", D_LLQUANT_NSTEPTYPE,
1447 			    D_LLQUANT_NSTEPVAL, D_LLQUANT_NSTEPMATCH,
1448 			    DTRACE_LLQUANTIZE_NSTEPSHIFT },
1449 			{ NULL }
1450 		};
1451 
1452 		assert(arg == 0);
1453 
1454 		for (i = 0; args[i].str != NULL; i++) {
1455 			if (llarg->dn_kind != DT_NODE_INT) {
1456 				dnerror(llarg, args[i].badtype, "llquantize( ) "
1457 				    "argument #%d (%s) must be an "
1458 				    "integer constant\n", i + 1, args[i].str);
1459 			}
1460 
1461 			if ((uint64_t)llarg->dn_value > UINT16_MAX) {
1462 				dnerror(llarg, args[i].badval, "llquantize( ) "
1463 				    "argument #%d (%s) must be an unsigned "
1464 				    "16-bit quantity\n", i + 1, args[i].str);
1465 			}
1466 
1467 			args[i].value = (uint16_t)llarg->dn_value;
1468 
1469 			assert(!(arg & ((uint64_t)UINT16_MAX <<
1470 			    args[i].shift)));
1471 			arg |= ((uint64_t)args[i].value << args[i].shift);
1472 			llarg = llarg->dn_list;
1473 		}
1474 
1475 		assert(arg != 0);
1476 
1477 		if (args[0].value < 2) {
1478 			dnerror(dnp, D_LLQUANT_FACTORSMALL, "llquantize( ) "
1479 			    "factor (argument #1) must be two or more\n");
1480 		}
1481 
1482 		if (args[1].value >= args[2].value) {
1483 			dnerror(dnp, D_LLQUANT_MAGRANGE, "llquantize( ) "
1484 			    "high magnitude (argument #3) must be greater "
1485 			    "than low magnitude (argument #2)\n");
1486 		}
1487 
1488 		if (args[3].value < args[0].value) {
1489 			dnerror(dnp, D_LLQUANT_FACTORNSTEPS, "llquantize( ) "
1490 			    "factor (argument #1) must be less than or "
1491 			    "equal to the number of linear steps per "
1492 			    "magnitude (argument #4)\n");
1493 		}
1494 
1495 		for (v = args[0].value; v < args[3].value; v *= args[0].value)
1496 			continue;
1497 
1498 		if ((args[3].value % args[0].value) || (v % args[3].value)) {
1499 			dnerror(dnp, D_LLQUANT_FACTOREVEN, "llquantize( ) "
1500 			    "factor (argument #1) must evenly divide the "
1501 			    "number of steps per magnitude (argument #4), "
1502 			    "and the number of steps per magnitude must evenly "
1503 			    "divide a power of the factor\n");
1504 		}
1505 
1506 		for (i = 0, order = 1; i <= args[2].value + 1; i++) {
1507 			if (order * args[0].value > order) {
1508 				order *= args[0].value;
1509 				continue;
1510 			}
1511 
1512 			dnerror(dnp, D_LLQUANT_MAGTOOBIG, "llquantize( ) "
1513 			    "factor (%d) raised to power of high magnitude "
1514 			    "(%d) plus 1 overflows 64-bits\n", args[0].value,
1515 			    args[2].value);
1516 		}
1517 
1518 		isp = (dt_idsig_t *)aid->di_data;
1519 
1520 		if (isp->dis_auxinfo == 0) {
1521 			/*
1522 			 * This is the first time we've seen an llquantize()
1523 			 * for this aggregation; we'll store our argument
1524 			 * as the auxiliary signature information.
1525 			 */
1526 			isp->dis_auxinfo = arg;
1527 		} else if ((oarg = isp->dis_auxinfo) != arg) {
1528 			/*
1529 			 * If we have seen this llquantize() before and the
1530 			 * argument doesn't match the original argument, pick
1531 			 * the original argument apart to concisely report the
1532 			 * mismatch.
1533 			 */
1534 			int expected = 0, found = 0;
1535 
1536 			for (i = 0; expected == found; i++) {
1537 				assert(args[i].str != NULL);
1538 
1539 				expected = (oarg >> args[i].shift) & UINT16_MAX;
1540 				found = (arg >> args[i].shift) & UINT16_MAX;
1541 			}
1542 
1543 			dnerror(dnp, args[i - 1].mismatch, "llquantize( ) "
1544 			    "%s (argument #%d) doesn't match previous "
1545 			    "declaration: expected %d, found %d\n",
1546 			    args[i - 1].str, i, expected, found);
1547 		}
1548 
1549 		incr = llarg;
1550 		argmax = 6;
1551 	}
1552 
1553 	if (fid->di_id == DTRACEAGG_QUANTIZE) {
1554 		incr = dnp->dn_aggfun->dn_args->dn_list;
1555 		argmax = 2;
1556 	}
1557 
1558 	if (incr != NULL) {
1559 		if (!dt_node_is_scalar(incr)) {
1560 			dnerror(dnp, D_PROTO_ARG, "%s( ) increment value "
1561 			    "(argument #%d) must be of scalar type\n",
1562 			    fid->di_name, argmax);
1563 		}
1564 
1565 		if ((anp = incr->dn_list) != NULL) {
1566 			int argc = argmax;
1567 
1568 			for (; anp != NULL; anp = anp->dn_list)
1569 				argc++;
1570 
1571 			dnerror(incr, D_PROTO_LEN, "%s( ) prototype "
1572 			    "mismatch: %d args passed, at most %d expected",
1573 			    fid->di_name, argc, argmax);
1574 		}
1575 
1576 		ap = dt_stmt_action(dtp, sdp);
1577 		n++;
1578 
1579 		dt_cg(yypcb, incr);
1580 		ap->dtad_difo = dt_as(yypcb);
1581 		ap->dtad_difo->dtdo_rtype = dt_void_rtype;
1582 		ap->dtad_kind = DTRACEACT_DIFEXPR;
1583 	}
1584 
1585 	assert(sdp->dtsd_aggdata == NULL);
1586 	sdp->dtsd_aggdata = aid;
1587 
1588 	ap = dt_stmt_action(dtp, sdp);
1589 	assert(fid->di_kind == DT_IDENT_AGGFUNC);
1590 	assert(DTRACEACT_ISAGG(fid->di_id));
1591 	ap->dtad_kind = fid->di_id;
1592 	ap->dtad_ntuple = n;
1593 	ap->dtad_arg = arg;
1594 
1595 	if (dnp->dn_aggfun->dn_args != NULL) {
1596 		dt_cg(yypcb, dnp->dn_aggfun->dn_args);
1597 		ap->dtad_difo = dt_as(yypcb);
1598 	}
1599 }
1600 
1601 static void
1602 dt_compile_one_clause(dtrace_hdl_t *dtp, dt_node_t *cnp, dt_node_t *pnp)
1603 {
1604 	dtrace_ecbdesc_t *edp;
1605 	dtrace_stmtdesc_t *sdp;
1606 	dt_node_t *dnp;
1607 
1608 	yylineno = pnp->dn_line;
1609 	dt_setcontext(dtp, pnp->dn_desc);
1610 	(void) dt_node_cook(cnp, DT_IDFLG_REF);
1611 
1612 	if (DT_TREEDUMP_PASS(dtp, 2))
1613 		dt_node_printr(cnp, stderr, 0);
1614 
1615 	if ((edp = dt_ecbdesc_create(dtp, pnp->dn_desc)) == NULL)
1616 		longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
1617 
1618 	assert(yypcb->pcb_ecbdesc == NULL);
1619 	yypcb->pcb_ecbdesc = edp;
1620 
1621 	if (cnp->dn_pred != NULL) {
1622 		dt_cg(yypcb, cnp->dn_pred);
1623 		edp->dted_pred.dtpdd_difo = dt_as(yypcb);
1624 	}
1625 
1626 	if (cnp->dn_acts == NULL) {
1627 		dt_stmt_append(dt_stmt_create(dtp, edp,
1628 		    cnp->dn_ctxattr, _dtrace_defattr), cnp);
1629 	}
1630 
1631 	for (dnp = cnp->dn_acts; dnp != NULL; dnp = dnp->dn_list) {
1632 		assert(yypcb->pcb_stmt == NULL);
1633 		sdp = dt_stmt_create(dtp, edp, cnp->dn_ctxattr, cnp->dn_attr);
1634 
1635 		switch (dnp->dn_kind) {
1636 		case DT_NODE_DEXPR:
1637 			if (dnp->dn_expr->dn_kind == DT_NODE_AGG)
1638 				dt_compile_agg(dtp, dnp->dn_expr, sdp);
1639 			else
1640 				dt_compile_exp(dtp, dnp, sdp);
1641 			break;
1642 		case DT_NODE_DFUNC:
1643 			dt_compile_fun(dtp, dnp, sdp);
1644 			break;
1645 		case DT_NODE_AGG:
1646 			dt_compile_agg(dtp, dnp, sdp);
1647 			break;
1648 		default:
1649 			dnerror(dnp, D_UNKNOWN, "internal error -- node kind "
1650 			    "%u is not a valid statement\n", dnp->dn_kind);
1651 		}
1652 
1653 		assert(yypcb->pcb_stmt == sdp);
1654 		dt_stmt_append(sdp, dnp);
1655 	}
1656 
1657 	assert(yypcb->pcb_ecbdesc == edp);
1658 	dt_ecbdesc_release(dtp, edp);
1659 	dt_endcontext(dtp);
1660 	yypcb->pcb_ecbdesc = NULL;
1661 }
1662 
1663 static void
1664 dt_compile_clause(dtrace_hdl_t *dtp, dt_node_t *cnp)
1665 {
1666 	dt_node_t *pnp;
1667 
1668 	for (pnp = cnp->dn_pdescs; pnp != NULL; pnp = pnp->dn_list)
1669 		dt_compile_one_clause(dtp, cnp, pnp);
1670 }
1671 
1672 static void
1673 dt_compile_xlator(dt_node_t *dnp)
1674 {
1675 	dt_xlator_t *dxp = dnp->dn_xlator;
1676 	dt_node_t *mnp;
1677 
1678 	for (mnp = dnp->dn_members; mnp != NULL; mnp = mnp->dn_list) {
1679 		assert(dxp->dx_membdif[mnp->dn_membid] == NULL);
1680 		dt_cg(yypcb, mnp);
1681 		dxp->dx_membdif[mnp->dn_membid] = dt_as(yypcb);
1682 	}
1683 }
1684 
1685 void
1686 dt_setcontext(dtrace_hdl_t *dtp, dtrace_probedesc_t *pdp)
1687 {
1688 	const dtrace_pattr_t *pap;
1689 	dt_probe_t *prp;
1690 	dt_provider_t *pvp;
1691 	dt_ident_t *idp;
1692 	char attrstr[8];
1693 	int err;
1694 	size_t prov_len;
1695 
1696 	/*
1697 	 * Both kernel and pid based providers are allowed to have names
1698 	 * ending with what could be interpreted as a number. We assume it's
1699 	 * a pid and that we may need to dynamically create probes for
1700 	 * that process if:
1701 	 *
1702 	 * (1) The provider doesn't exist, or,
1703 	 * (2) The provider exists and has DTRACE_PRIV_PROC privilege.
1704 	 *
1705 	 * On an error, dt_pid_create_probes() will set the error message
1706 	 * and tag -- we just have to longjmp() out of here.
1707 	 */
1708 
1709 	prov_len = strlen(pdp->dtpd_provider);
1710 
1711 	if ((prov_len > 0 && isdigit(pdp->dtpd_provider[prov_len - 1])) &&
1712 	    ((pvp = dt_provider_lookup(dtp, pdp->dtpd_provider)) == NULL ||
1713 	    pvp->pv_desc.dtvd_priv.dtpp_flags & DTRACE_PRIV_PROC) &&
1714 	    dt_pid_create_probes(pdp, dtp, yypcb) != 0) {
1715 		longjmp(yypcb->pcb_jmpbuf, EDT_COMPILER);
1716 	}
1717 
1718 	/*
1719 	 * Call dt_probe_info() to get the probe arguments and attributes.  If
1720 	 * a representative probe is found, set 'pap' to the probe provider's
1721 	 * attributes.  Otherwise set 'pap' to default Unstable attributes.
1722 	 */
1723 	if ((prp = dt_probe_info(dtp, pdp, &yypcb->pcb_pinfo)) == NULL) {
1724 		pap = &_dtrace_prvdesc;
1725 		err = dtrace_errno(dtp);
1726 		bzero(&yypcb->pcb_pinfo, sizeof (dtrace_probeinfo_t));
1727 		yypcb->pcb_pinfo.dtp_attr = pap->dtpa_provider;
1728 		yypcb->pcb_pinfo.dtp_arga = pap->dtpa_args;
1729 	} else {
1730 		pap = &prp->pr_pvp->pv_desc.dtvd_attr;
1731 		err = 0;
1732 	}
1733 
1734 	if (err == EDT_NOPROBE && !(yypcb->pcb_cflags & DTRACE_C_ZDEFS)) {
1735 		xyerror(D_PDESC_ZERO, "probe description %s:%s:%s:%s does not "
1736 		    "match any probes\n", pdp->dtpd_provider, pdp->dtpd_mod,
1737 		    pdp->dtpd_func, pdp->dtpd_name);
1738 	}
1739 
1740 	if (err != EDT_NOPROBE && err != EDT_UNSTABLE && err != 0)
1741 		xyerror(D_PDESC_INVAL, "%s\n", dtrace_errmsg(dtp, err));
1742 
1743 	dt_dprintf("set context to %s:%s:%s:%s [%u] prp=%p attr=%s argc=%d\n",
1744 	    pdp->dtpd_provider, pdp->dtpd_mod, pdp->dtpd_func, pdp->dtpd_name,
1745 	    pdp->dtpd_id, (void *)prp, dt_attr_str(yypcb->pcb_pinfo.dtp_attr,
1746 	    attrstr, sizeof (attrstr)), yypcb->pcb_pinfo.dtp_argc);
1747 
1748 	/*
1749 	 * Reset the stability attributes of D global variables that vary
1750 	 * based on the attributes of the provider and context itself.
1751 	 */
1752 	if ((idp = dt_idhash_lookup(dtp->dt_globals, "probeprov")) != NULL)
1753 		idp->di_attr = pap->dtpa_provider;
1754 	if ((idp = dt_idhash_lookup(dtp->dt_globals, "probemod")) != NULL)
1755 		idp->di_attr = pap->dtpa_mod;
1756 	if ((idp = dt_idhash_lookup(dtp->dt_globals, "probefunc")) != NULL)
1757 		idp->di_attr = pap->dtpa_func;
1758 	if ((idp = dt_idhash_lookup(dtp->dt_globals, "probename")) != NULL)
1759 		idp->di_attr = pap->dtpa_name;
1760 	if ((idp = dt_idhash_lookup(dtp->dt_globals, "args")) != NULL)
1761 		idp->di_attr = pap->dtpa_args;
1762 
1763 	yypcb->pcb_pdesc = pdp;
1764 	yypcb->pcb_probe = prp;
1765 }
1766 
1767 /*
1768  * Reset context-dependent variables and state at the end of cooking a D probe
1769  * definition clause.  This ensures that external declarations between clauses
1770  * do not reference any stale context-dependent data from the previous clause.
1771  */
1772 void
1773 dt_endcontext(dtrace_hdl_t *dtp)
1774 {
1775 	static const char *const cvars[] = {
1776 		"probeprov", "probemod", "probefunc", "probename", "args", NULL
1777 	};
1778 
1779 	dt_ident_t *idp;
1780 	int i;
1781 
1782 	for (i = 0; cvars[i] != NULL; i++) {
1783 		if ((idp = dt_idhash_lookup(dtp->dt_globals, cvars[i])) != NULL)
1784 			idp->di_attr = _dtrace_defattr;
1785 	}
1786 
1787 	yypcb->pcb_pdesc = NULL;
1788 	yypcb->pcb_probe = NULL;
1789 }
1790 
1791 static int
1792 dt_reduceid(dt_idhash_t *dhp, dt_ident_t *idp, dtrace_hdl_t *dtp)
1793 {
1794 	if (idp->di_vers != 0 && idp->di_vers > dtp->dt_vmax)
1795 		dt_idhash_delete(dhp, idp);
1796 
1797 	return (0);
1798 }
1799 
1800 /*
1801  * When dtrace_setopt() is called for "version", it calls dt_reduce() to remove
1802  * any identifiers or translators that have been previously defined as bound to
1803  * a version greater than the specified version.  Therefore, in our current
1804  * version implementation, establishing a binding is a one-way transformation.
1805  * In addition, no versioning is currently provided for types as our .d library
1806  * files do not define any types and we reserve prefixes DTRACE_ and dtrace_
1807  * for our exclusive use.  If required, type versioning will require more work.
1808  */
1809 int
1810 dt_reduce(dtrace_hdl_t *dtp, dt_version_t v)
1811 {
1812 	char s[DT_VERSION_STRMAX];
1813 	dt_xlator_t *dxp, *nxp;
1814 
1815 	if (v > dtp->dt_vmax)
1816 		return (dt_set_errno(dtp, EDT_VERSREDUCED));
1817 	else if (v == dtp->dt_vmax)
1818 		return (0); /* no reduction necessary */
1819 
1820 	dt_dprintf("reducing api version to %s\n",
1821 	    dt_version_num2str(v, s, sizeof (s)));
1822 
1823 	dtp->dt_vmax = v;
1824 
1825 	for (dxp = dt_list_next(&dtp->dt_xlators); dxp != NULL; dxp = nxp) {
1826 		nxp = dt_list_next(dxp);
1827 		if ((dxp->dx_souid.di_vers != 0 && dxp->dx_souid.di_vers > v) ||
1828 		    (dxp->dx_ptrid.di_vers != 0 && dxp->dx_ptrid.di_vers > v))
1829 			dt_list_delete(&dtp->dt_xlators, dxp);
1830 	}
1831 
1832 	(void) dt_idhash_iter(dtp->dt_macros, (dt_idhash_f *)dt_reduceid, dtp);
1833 	(void) dt_idhash_iter(dtp->dt_aggs, (dt_idhash_f *)dt_reduceid, dtp);
1834 	(void) dt_idhash_iter(dtp->dt_globals, (dt_idhash_f *)dt_reduceid, dtp);
1835 	(void) dt_idhash_iter(dtp->dt_tls, (dt_idhash_f *)dt_reduceid, dtp);
1836 
1837 	return (0);
1838 }
1839 
1840 /*
1841  * Fork and exec the cpp(1) preprocessor to run over the specified input file,
1842  * and return a FILE handle for the cpp output.  We use the /dev/fd filesystem
1843  * here to simplify the code by leveraging file descriptor inheritance.
1844  */
1845 static FILE *
1846 dt_preproc(dtrace_hdl_t *dtp, FILE *ifp)
1847 {
1848 	int argc = dtp->dt_cpp_argc;
1849 	char **argv = malloc(sizeof (char *) * (argc + 5));
1850 	FILE *ofp = tmpfile();
1851 
1852 #ifdef illumos
1853 	char ipath[20], opath[20]; /* big enough for /dev/fd/ + INT_MAX + \0 */
1854 #endif
1855 	char verdef[32]; /* big enough for -D__SUNW_D_VERSION=0x%08x + \0 */
1856 
1857 	struct sigaction act, oact;
1858 	sigset_t mask, omask;
1859 
1860 	int wstat, estat;
1861 	pid_t pid;
1862 #ifdef illumos
1863 	off64_t off;
1864 #else
1865 	off_t off = 0;
1866 #endif
1867 	int c;
1868 
1869 	if (argv == NULL || ofp == NULL) {
1870 		(void) dt_set_errno(dtp, errno);
1871 		goto err;
1872 	}
1873 
1874 	/*
1875 	 * If the input is a seekable file, see if it is an interpreter file.
1876 	 * If we see #!, seek past the first line because cpp will choke on it.
1877 	 * We start cpp just prior to the \n at the end of this line so that
1878 	 * it still sees the newline, ensuring that #line values are correct.
1879 	 */
1880 	if (isatty(fileno(ifp)) == 0 && (off = ftello64(ifp)) != -1) {
1881 		if ((c = fgetc(ifp)) == '#' && (c = fgetc(ifp)) == '!') {
1882 			for (off += 2; c != '\n'; off++) {
1883 				if ((c = fgetc(ifp)) == EOF)
1884 					break;
1885 			}
1886 			if (c == '\n')
1887 				off--; /* start cpp just prior to \n */
1888 		}
1889 		(void) fflush(ifp);
1890 		(void) fseeko64(ifp, off, SEEK_SET);
1891 	}
1892 
1893 #ifdef illumos
1894 	(void) snprintf(ipath, sizeof (ipath), "/dev/fd/%d", fileno(ifp));
1895 	(void) snprintf(opath, sizeof (opath), "/dev/fd/%d", fileno(ofp));
1896 #endif
1897 
1898 	bcopy(dtp->dt_cpp_argv, argv, sizeof (char *) * argc);
1899 
1900 	(void) snprintf(verdef, sizeof (verdef),
1901 	    "-D__SUNW_D_VERSION=0x%08x", dtp->dt_vmax);
1902 	argv[argc++] = verdef;
1903 
1904 #ifdef illumos
1905 	switch (dtp->dt_stdcmode) {
1906 	case DT_STDC_XA:
1907 	case DT_STDC_XT:
1908 		argv[argc++] = "-D__STDC__=0";
1909 		break;
1910 	case DT_STDC_XC:
1911 		argv[argc++] = "-D__STDC__=1";
1912 		break;
1913 	}
1914 
1915 	argv[argc++] = ipath;
1916 	argv[argc++] = opath;
1917 #else
1918 	argv[argc++] = "-P";
1919 #endif
1920 	argv[argc] = NULL;
1921 
1922 	/*
1923 	 * libdtrace must be able to be embedded in other programs that may
1924 	 * include application-specific signal handlers.  Therefore, if we
1925 	 * need to fork to run cpp(1), we must avoid generating a SIGCHLD
1926 	 * that could confuse the containing application.  To do this,
1927 	 * we block SIGCHLD and reset its disposition to SIG_DFL.
1928 	 * We restore our signal state once we are done.
1929 	 */
1930 	(void) sigemptyset(&mask);
1931 	(void) sigaddset(&mask, SIGCHLD);
1932 	(void) sigprocmask(SIG_BLOCK, &mask, &omask);
1933 
1934 	bzero(&act, sizeof (act));
1935 	act.sa_handler = SIG_DFL;
1936 	(void) sigaction(SIGCHLD, &act, &oact);
1937 
1938 	if ((pid = fork1()) == -1) {
1939 		(void) sigaction(SIGCHLD, &oact, NULL);
1940 		(void) sigprocmask(SIG_SETMASK, &omask, NULL);
1941 		(void) dt_set_errno(dtp, EDT_CPPFORK);
1942 		goto err;
1943 	}
1944 
1945 	if (pid == 0) {
1946 #ifndef illumos
1947 		if (isatty(fileno(ifp)) == 0)
1948 			lseek(fileno(ifp), off, SEEK_SET);
1949 		dup2(fileno(ifp), 0);
1950 		dup2(fileno(ofp), 1);
1951 #endif
1952 		(void) execvp(dtp->dt_cpp_path, argv);
1953 		_exit(errno == ENOENT ? 127 : 126);
1954 	}
1955 
1956 	do {
1957 		dt_dprintf("waiting for %s (PID %d)\n", dtp->dt_cpp_path,
1958 		    (int)pid);
1959 	} while (waitpid(pid, &wstat, 0) == -1 && errno == EINTR);
1960 
1961 	(void) sigaction(SIGCHLD, &oact, NULL);
1962 	(void) sigprocmask(SIG_SETMASK, &omask, NULL);
1963 
1964 	dt_dprintf("%s returned exit status 0x%x\n", dtp->dt_cpp_path, wstat);
1965 	estat = WIFEXITED(wstat) ? WEXITSTATUS(wstat) : -1;
1966 
1967 	if (estat != 0) {
1968 		switch (estat) {
1969 		case 126:
1970 			(void) dt_set_errno(dtp, EDT_CPPEXEC);
1971 			break;
1972 		case 127:
1973 			(void) dt_set_errno(dtp, EDT_CPPENT);
1974 			break;
1975 		default:
1976 			(void) dt_set_errno(dtp, EDT_CPPERR);
1977 		}
1978 		goto err;
1979 	}
1980 
1981 	free(argv);
1982 	(void) fflush(ofp);
1983 	(void) fseek(ofp, 0, SEEK_SET);
1984 	return (ofp);
1985 
1986 err:
1987 	free(argv);
1988 	(void) fclose(ofp);
1989 	return (NULL);
1990 }
1991 
1992 static void
1993 dt_lib_depend_error(dtrace_hdl_t *dtp, const char *format, ...)
1994 {
1995 	va_list ap;
1996 
1997 	va_start(ap, format);
1998 	dt_set_errmsg(dtp, NULL, NULL, NULL, 0, format, ap);
1999 	va_end(ap);
2000 }
2001 
2002 int
2003 dt_lib_depend_add(dtrace_hdl_t *dtp, dt_list_t *dlp, const char *arg)
2004 {
2005 	dt_lib_depend_t *dld;
2006 	const char *end;
2007 
2008 	assert(arg != NULL);
2009 
2010 	if ((end = strrchr(arg, '/')) == NULL)
2011 		return (dt_set_errno(dtp, EINVAL));
2012 
2013 	if ((dld = dt_zalloc(dtp, sizeof (dt_lib_depend_t))) == NULL)
2014 		return (-1);
2015 
2016 	if ((dld->dtld_libpath = dt_alloc(dtp, MAXPATHLEN)) == NULL) {
2017 		dt_free(dtp, dld);
2018 		return (-1);
2019 	}
2020 
2021 	(void) strlcpy(dld->dtld_libpath, arg, end - arg + 2);
2022 	if ((dld->dtld_library = strdup(arg)) == NULL) {
2023 		dt_free(dtp, dld->dtld_libpath);
2024 		dt_free(dtp, dld);
2025 		return (dt_set_errno(dtp, EDT_NOMEM));
2026 	}
2027 
2028 	dt_list_append(dlp, dld);
2029 	return (0);
2030 }
2031 
2032 dt_lib_depend_t *
2033 dt_lib_depend_lookup(dt_list_t *dld, const char *arg)
2034 {
2035 	dt_lib_depend_t *dldn;
2036 
2037 	for (dldn = dt_list_next(dld); dldn != NULL;
2038 	    dldn = dt_list_next(dldn)) {
2039 		if (strcmp(dldn->dtld_library, arg) == 0)
2040 			return (dldn);
2041 	}
2042 
2043 	return (NULL);
2044 }
2045 
2046 /*
2047  * Go through all the library files, and, if any library dependencies exist for
2048  * that file, add it to that node's list of dependents. The result of this
2049  * will be a graph which can then be topologically sorted to produce a
2050  * compilation order.
2051  */
2052 static int
2053 dt_lib_build_graph(dtrace_hdl_t *dtp)
2054 {
2055 	dt_lib_depend_t *dld, *dpld;
2056 
2057 	for (dld = dt_list_next(&dtp->dt_lib_dep); dld != NULL;
2058 	    dld = dt_list_next(dld)) {
2059 		char *library = dld->dtld_library;
2060 
2061 		for (dpld = dt_list_next(&dld->dtld_dependencies); dpld != NULL;
2062 		    dpld = dt_list_next(dpld)) {
2063 			dt_lib_depend_t *dlda;
2064 
2065 			if ((dlda = dt_lib_depend_lookup(&dtp->dt_lib_dep,
2066 			    dpld->dtld_library)) == NULL) {
2067 				dt_lib_depend_error(dtp,
2068 				    "Invalid library dependency in %s: %s\n",
2069 				    dld->dtld_library, dpld->dtld_library);
2070 
2071 				return (dt_set_errno(dtp, EDT_COMPILER));
2072 			}
2073 
2074 			if ((dt_lib_depend_add(dtp, &dlda->dtld_dependents,
2075 			    library)) != 0) {
2076 				return (-1); /* preserve dt_errno */
2077 			}
2078 		}
2079 	}
2080 	return (0);
2081 }
2082 
2083 static int
2084 dt_topo_sort(dtrace_hdl_t *dtp, dt_lib_depend_t *dld, int *count)
2085 {
2086 	dt_lib_depend_t *dpld, *dlda, *new;
2087 
2088 	dld->dtld_start = ++(*count);
2089 
2090 	for (dpld = dt_list_next(&dld->dtld_dependents); dpld != NULL;
2091 	    dpld = dt_list_next(dpld)) {
2092 		dlda = dt_lib_depend_lookup(&dtp->dt_lib_dep,
2093 		    dpld->dtld_library);
2094 		assert(dlda != NULL);
2095 
2096 		if (dlda->dtld_start == 0 &&
2097 		    dt_topo_sort(dtp, dlda, count) == -1)
2098 			return (-1);
2099 	}
2100 
2101 	if ((new = dt_zalloc(dtp, sizeof (dt_lib_depend_t))) == NULL)
2102 		return (-1);
2103 
2104 	if ((new->dtld_library = strdup(dld->dtld_library)) == NULL) {
2105 		dt_free(dtp, new);
2106 		return (dt_set_errno(dtp, EDT_NOMEM));
2107 	}
2108 
2109 	new->dtld_start = dld->dtld_start;
2110 	new->dtld_finish = dld->dtld_finish = ++(*count);
2111 	dt_list_prepend(&dtp->dt_lib_dep_sorted, new);
2112 
2113 	dt_dprintf("library %s sorted (%d/%d)\n", new->dtld_library,
2114 	    new->dtld_start, new->dtld_finish);
2115 
2116 	return (0);
2117 }
2118 
2119 static int
2120 dt_lib_depend_sort(dtrace_hdl_t *dtp)
2121 {
2122 	dt_lib_depend_t *dld, *dpld, *dlda;
2123 	int count = 0;
2124 
2125 	if (dt_lib_build_graph(dtp) == -1)
2126 		return (-1); /* preserve dt_errno */
2127 
2128 	/*
2129 	 * Perform a topological sort of the graph that hangs off
2130 	 * dtp->dt_lib_dep. The result of this process will be a
2131 	 * dependency ordered list located at dtp->dt_lib_dep_sorted.
2132 	 */
2133 	for (dld = dt_list_next(&dtp->dt_lib_dep); dld != NULL;
2134 	    dld = dt_list_next(dld)) {
2135 		if (dld->dtld_start == 0 &&
2136 		    dt_topo_sort(dtp, dld, &count) == -1)
2137 			return (-1); /* preserve dt_errno */;
2138 	}
2139 
2140 	/*
2141 	 * Check the graph for cycles. If an ancestor's finishing time is
2142 	 * less than any of its dependent's finishing times then a back edge
2143 	 * exists in the graph and this is a cycle.
2144 	 */
2145 	for (dld = dt_list_next(&dtp->dt_lib_dep); dld != NULL;
2146 	    dld = dt_list_next(dld)) {
2147 		for (dpld = dt_list_next(&dld->dtld_dependents); dpld != NULL;
2148 		    dpld = dt_list_next(dpld)) {
2149 			dlda = dt_lib_depend_lookup(&dtp->dt_lib_dep_sorted,
2150 			    dpld->dtld_library);
2151 			assert(dlda != NULL);
2152 
2153 			if (dlda->dtld_finish > dld->dtld_finish) {
2154 				dt_lib_depend_error(dtp,
2155 				    "Cyclic dependency detected: %s => %s\n",
2156 				    dld->dtld_library, dpld->dtld_library);
2157 
2158 				return (dt_set_errno(dtp, EDT_COMPILER));
2159 			}
2160 		}
2161 	}
2162 
2163 	return (0);
2164 }
2165 
2166 static void
2167 dt_lib_depend_free(dtrace_hdl_t *dtp)
2168 {
2169 	dt_lib_depend_t *dld, *dlda;
2170 
2171 	while ((dld = dt_list_next(&dtp->dt_lib_dep)) != NULL) {
2172 		while ((dlda = dt_list_next(&dld->dtld_dependencies)) != NULL) {
2173 			dt_list_delete(&dld->dtld_dependencies, dlda);
2174 			dt_free(dtp, dlda->dtld_library);
2175 			dt_free(dtp, dlda->dtld_libpath);
2176 			dt_free(dtp, dlda);
2177 		}
2178 		while ((dlda = dt_list_next(&dld->dtld_dependents)) != NULL) {
2179 			dt_list_delete(&dld->dtld_dependents, dlda);
2180 			dt_free(dtp, dlda->dtld_library);
2181 			dt_free(dtp, dlda->dtld_libpath);
2182 			dt_free(dtp, dlda);
2183 		}
2184 		dt_list_delete(&dtp->dt_lib_dep, dld);
2185 		dt_free(dtp, dld->dtld_library);
2186 		dt_free(dtp, dld->dtld_libpath);
2187 		dt_free(dtp, dld);
2188 	}
2189 
2190 	while ((dld = dt_list_next(&dtp->dt_lib_dep_sorted)) != NULL) {
2191 		dt_list_delete(&dtp->dt_lib_dep_sorted, dld);
2192 		dt_free(dtp, dld->dtld_library);
2193 		dt_free(dtp, dld);
2194 	}
2195 }
2196 
2197 /*
2198  * Open all the .d library files found in the specified directory and
2199  * compile each one of them.  We silently ignore any missing directories and
2200  * other files found therein.  We only fail (and thereby fail dt_load_libs()) if
2201  * we fail to compile a library and the error is something other than #pragma D
2202  * depends_on.  Dependency errors are silently ignored to permit a library
2203  * directory to contain libraries which may not be accessible depending on our
2204  * privileges.
2205  */
2206 static int
2207 dt_load_libs_dir(dtrace_hdl_t *dtp, const char *path)
2208 {
2209 	struct dirent *dp;
2210 	const char *p, *end;
2211 	DIR *dirp;
2212 
2213 	char fname[PATH_MAX];
2214 	FILE *fp;
2215 	void *rv;
2216 	dt_lib_depend_t *dld;
2217 
2218 	if ((dirp = opendir(path)) == NULL) {
2219 		dt_dprintf("skipping lib dir %s: %s\n", path, strerror(errno));
2220 		return (0);
2221 	}
2222 
2223 	/* First, parse each file for library dependencies. */
2224 	while ((dp = readdir(dirp)) != NULL) {
2225 		if ((p = strrchr(dp->d_name, '.')) == NULL || strcmp(p, ".d"))
2226 			continue; /* skip any filename not ending in .d */
2227 
2228 		(void) snprintf(fname, sizeof (fname),
2229 		    "%s/%s", path, dp->d_name);
2230 
2231 		if ((fp = fopen(fname, "r")) == NULL) {
2232 			dt_dprintf("skipping library %s: %s\n",
2233 			    fname, strerror(errno));
2234 			continue;
2235 		}
2236 
2237 		/*
2238 		 * Skip files whose name match an already processed library
2239 		 */
2240 		for (dld = dt_list_next(&dtp->dt_lib_dep); dld != NULL;
2241 		    dld = dt_list_next(dld)) {
2242 			end = strrchr(dld->dtld_library, '/');
2243 			/* dt_lib_depend_add ensures this */
2244 			assert(end != NULL);
2245 			if (strcmp(end + 1, dp->d_name) == 0)
2246 				break;
2247 		}
2248 
2249 		if (dld != NULL) {
2250 			dt_dprintf("skipping library %s, already processed "
2251 			    "library with the same name: %s", dp->d_name,
2252 			    dld->dtld_library);
2253 			(void) fclose(fp);
2254 			continue;
2255 		}
2256 
2257 		dtp->dt_filetag = fname;
2258 		if (dt_lib_depend_add(dtp, &dtp->dt_lib_dep, fname) != 0) {
2259 			(void) fclose(fp);
2260 			return (-1); /* preserve dt_errno */
2261 		}
2262 
2263 		rv = dt_compile(dtp, DT_CTX_DPROG,
2264 		    DTRACE_PROBESPEC_NAME, NULL,
2265 		    DTRACE_C_EMPTY | DTRACE_C_CTL, 0, NULL, fp, NULL);
2266 
2267 		if (rv != NULL && dtp->dt_errno &&
2268 		    (dtp->dt_errno != EDT_COMPILER ||
2269 		    dtp->dt_errtag != dt_errtag(D_PRAGMA_DEPEND))) {
2270 			(void) fclose(fp);
2271 			return (-1); /* preserve dt_errno */
2272 		}
2273 
2274 		if (dtp->dt_errno)
2275 			dt_dprintf("error parsing library %s: %s\n",
2276 			    fname, dtrace_errmsg(dtp, dtrace_errno(dtp)));
2277 
2278 		(void) fclose(fp);
2279 		dtp->dt_filetag = NULL;
2280 	}
2281 
2282 	(void) closedir(dirp);
2283 
2284 	return (0);
2285 }
2286 
2287 /*
2288  * Perform a topological sorting of all the libraries found across the entire
2289  * dt_lib_path.  Once sorted, compile each one in topological order to cache its
2290  * inlines and translators, etc.  We silently ignore any missing directories and
2291  * other files found therein. We only fail (and thereby fail dt_load_libs()) if
2292  * we fail to compile a library and the error is something other than #pragma D
2293  * depends_on.  Dependency errors are silently ignored to permit a library
2294  * directory to contain libraries which may not be accessible depending on our
2295  * privileges.
2296  */
2297 static int
2298 dt_load_libs_sort(dtrace_hdl_t *dtp)
2299 {
2300 	dtrace_prog_t *pgp;
2301 	FILE *fp;
2302 	dt_lib_depend_t *dld;
2303 
2304 	/*
2305 	 * Finish building the graph containing the library dependencies
2306 	 * and perform a topological sort to generate an ordered list
2307 	 * for compilation.
2308 	 */
2309 	if (dt_lib_depend_sort(dtp) == -1)
2310 		goto err;
2311 
2312 	for (dld = dt_list_next(&dtp->dt_lib_dep_sorted); dld != NULL;
2313 	    dld = dt_list_next(dld)) {
2314 
2315 		if ((fp = fopen(dld->dtld_library, "r")) == NULL) {
2316 			dt_dprintf("skipping library %s: %s\n",
2317 			    dld->dtld_library, strerror(errno));
2318 			continue;
2319 		}
2320 
2321 		dtp->dt_filetag = dld->dtld_library;
2322 		pgp = dtrace_program_fcompile(dtp, fp, DTRACE_C_EMPTY, 0, NULL);
2323 		(void) fclose(fp);
2324 		dtp->dt_filetag = NULL;
2325 
2326 		if (pgp == NULL && (dtp->dt_errno != EDT_COMPILER ||
2327 		    dtp->dt_errtag != dt_errtag(D_PRAGMA_DEPEND)))
2328 			goto err;
2329 
2330 		if (pgp == NULL) {
2331 			dt_dprintf("skipping library %s: %s\n",
2332 			    dld->dtld_library,
2333 			    dtrace_errmsg(dtp, dtrace_errno(dtp)));
2334 		} else {
2335 			dld->dtld_loaded = B_TRUE;
2336 			dt_program_destroy(dtp, pgp);
2337 		}
2338 	}
2339 
2340 	dt_lib_depend_free(dtp);
2341 	return (0);
2342 
2343 err:
2344 	dt_lib_depend_free(dtp);
2345 	return (-1); /* preserve dt_errno */
2346 }
2347 
2348 /*
2349  * Load the contents of any appropriate DTrace .d library files.  These files
2350  * contain inlines and translators that will be cached by the compiler.  We
2351  * defer this activity until the first compile to permit libdtrace clients to
2352  * add their own library directories and so that we can properly report errors.
2353  */
2354 static int
2355 dt_load_libs(dtrace_hdl_t *dtp)
2356 {
2357 	dt_dirpath_t *dirp;
2358 
2359 	if (dtp->dt_cflags & DTRACE_C_NOLIBS)
2360 		return (0); /* libraries already processed */
2361 
2362 	dtp->dt_cflags |= DTRACE_C_NOLIBS;
2363 
2364 	/*
2365 	 * /usr/lib/dtrace is always at the head of the list. The rest of the
2366 	 * list is specified in the precedence order the user requested. Process
2367 	 * everything other than the head first. DTRACE_C_NOLIBS has already
2368 	 * been spcified so dt_vopen will ensure that there is always one entry
2369 	 * in dt_lib_path.
2370 	 */
2371 	for (dirp = dt_list_next(dt_list_next(&dtp->dt_lib_path));
2372 	    dirp != NULL; dirp = dt_list_next(dirp)) {
2373 		if (dt_load_libs_dir(dtp, dirp->dir_path) != 0) {
2374 			dtp->dt_cflags &= ~DTRACE_C_NOLIBS;
2375 			return (-1); /* errno is set for us */
2376 		}
2377 	}
2378 
2379 	/* Handle /usr/lib/dtrace */
2380 	dirp = dt_list_next(&dtp->dt_lib_path);
2381 	if (dt_load_libs_dir(dtp, dirp->dir_path) != 0) {
2382 		dtp->dt_cflags &= ~DTRACE_C_NOLIBS;
2383 		return (-1); /* errno is set for us */
2384 	}
2385 
2386 	if (dt_load_libs_sort(dtp) < 0)
2387 		return (-1); /* errno is set for us */
2388 
2389 	return (0);
2390 }
2391 
2392 static void *
2393 dt_compile(dtrace_hdl_t *dtp, int context, dtrace_probespec_t pspec, void *arg,
2394     uint_t cflags, int argc, char *const argv[], FILE *fp, const char *s)
2395 {
2396 	dt_node_t *dnp;
2397 	dt_decl_t *ddp;
2398 	dt_pcb_t pcb;
2399 	void *volatile rv;
2400 	int err;
2401 
2402 	if ((fp == NULL && s == NULL) || (cflags & ~DTRACE_C_MASK) != 0) {
2403 		(void) dt_set_errno(dtp, EINVAL);
2404 		return (NULL);
2405 	}
2406 
2407 	if (dt_list_next(&dtp->dt_lib_path) != NULL && dt_load_libs(dtp) != 0)
2408 		return (NULL); /* errno is set for us */
2409 
2410 	if (dtp->dt_globals->dh_nelems != 0)
2411 		(void) dt_idhash_iter(dtp->dt_globals, dt_idreset, NULL);
2412 
2413 	if (dtp->dt_tls->dh_nelems != 0)
2414 		(void) dt_idhash_iter(dtp->dt_tls, dt_idreset, NULL);
2415 
2416 	if (fp && (cflags & DTRACE_C_CPP) && (fp = dt_preproc(dtp, fp)) == NULL)
2417 		return (NULL); /* errno is set for us */
2418 
2419 	dt_pcb_push(dtp, &pcb);
2420 
2421 	pcb.pcb_fileptr = fp;
2422 	pcb.pcb_string = s;
2423 	pcb.pcb_strptr = s;
2424 	pcb.pcb_strlen = s ? strlen(s) : 0;
2425 	pcb.pcb_sargc = argc;
2426 	pcb.pcb_sargv = argv;
2427 	pcb.pcb_sflagv = argc ? calloc(argc, sizeof (ushort_t)) : NULL;
2428 	pcb.pcb_pspec = pspec;
2429 	pcb.pcb_cflags = dtp->dt_cflags | cflags;
2430 	pcb.pcb_amin = dtp->dt_amin;
2431 	pcb.pcb_yystate = -1;
2432 	pcb.pcb_context = context;
2433 	pcb.pcb_token = context;
2434 
2435 	if (context != DT_CTX_DPROG)
2436 		yybegin(YYS_EXPR);
2437 	else if (cflags & DTRACE_C_CTL)
2438 		yybegin(YYS_CONTROL);
2439 	else
2440 		yybegin(YYS_CLAUSE);
2441 
2442 	if ((err = setjmp(yypcb->pcb_jmpbuf)) != 0)
2443 		goto out;
2444 
2445 	if (yypcb->pcb_sargc != 0 && yypcb->pcb_sflagv == NULL)
2446 		longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
2447 
2448 	yypcb->pcb_idents = dt_idhash_create("ambiguous", NULL, 0, 0);
2449 	yypcb->pcb_locals = dt_idhash_create("clause local", NULL,
2450 	    DIF_VAR_OTHER_UBASE, DIF_VAR_OTHER_MAX);
2451 
2452 	if (yypcb->pcb_idents == NULL || yypcb->pcb_locals == NULL)
2453 		longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
2454 
2455 	/*
2456 	 * Invoke the parser to evaluate the D source code.  If any errors
2457 	 * occur during parsing, an error function will be called and we
2458 	 * will longjmp back to pcb_jmpbuf to abort.  If parsing succeeds,
2459 	 * we optionally display the parse tree if debugging is enabled.
2460 	 */
2461 	if (yyparse() != 0 || yypcb->pcb_root == NULL)
2462 		xyerror(D_EMPTY, "empty D program translation unit\n");
2463 
2464 	yybegin(YYS_DONE);
2465 
2466 	if (cflags & DTRACE_C_CTL)
2467 		goto out;
2468 
2469 	if (context != DT_CTX_DTYPE && DT_TREEDUMP_PASS(dtp, 1))
2470 		dt_node_printr(yypcb->pcb_root, stderr, 0);
2471 
2472 	if (yypcb->pcb_pragmas != NULL)
2473 		(void) dt_idhash_iter(yypcb->pcb_pragmas, dt_idpragma, NULL);
2474 
2475 	if (argc > 1 && !(yypcb->pcb_cflags & DTRACE_C_ARGREF) &&
2476 	    !(yypcb->pcb_sflagv[argc - 1] & DT_IDFLG_REF)) {
2477 		xyerror(D_MACRO_UNUSED, "extraneous argument '%s' ($%d is "
2478 		    "not referenced)\n", yypcb->pcb_sargv[argc - 1], argc - 1);
2479 	}
2480 
2481 	/*
2482 	 * Perform sugar transformations (for "if" / "else") and replace the
2483 	 * existing clause chain with the new one.
2484 	 */
2485 	if (context == DT_CTX_DPROG) {
2486 		dt_node_t *dnp, *next_dnp;
2487 		dt_node_t *new_list = NULL;
2488 
2489 		for (dnp = yypcb->pcb_root->dn_list;
2490 		    dnp != NULL; dnp = next_dnp) {
2491 			/* remove this node from the list */
2492 			next_dnp = dnp->dn_list;
2493 			dnp->dn_list = NULL;
2494 
2495 			if (dnp->dn_kind == DT_NODE_CLAUSE)
2496 				dnp = dt_compile_sugar(dtp, dnp);
2497 			/* append node to the new list */
2498 			new_list = dt_node_link(new_list, dnp);
2499 		}
2500 		yypcb->pcb_root->dn_list = new_list;
2501 	}
2502 
2503 	/*
2504 	 * If we have successfully created a parse tree for a D program, loop
2505 	 * over the clauses and actions and instantiate the corresponding
2506 	 * libdtrace program.  If we are parsing a D expression, then we
2507 	 * simply run the code generator and assembler on the resulting tree.
2508 	 */
2509 	switch (context) {
2510 	case DT_CTX_DPROG:
2511 		assert(yypcb->pcb_root->dn_kind == DT_NODE_PROG);
2512 
2513 		if ((dnp = yypcb->pcb_root->dn_list) == NULL &&
2514 		    !(yypcb->pcb_cflags & DTRACE_C_EMPTY))
2515 			xyerror(D_EMPTY, "empty D program translation unit\n");
2516 
2517 		if ((yypcb->pcb_prog = dt_program_create(dtp)) == NULL)
2518 			longjmp(yypcb->pcb_jmpbuf, dtrace_errno(dtp));
2519 
2520 		for (; dnp != NULL; dnp = dnp->dn_list) {
2521 			switch (dnp->dn_kind) {
2522 			case DT_NODE_CLAUSE:
2523 				if (DT_TREEDUMP_PASS(dtp, 4))
2524 					dt_printd(dnp, stderr, 0);
2525 				dt_compile_clause(dtp, dnp);
2526 				break;
2527 			case DT_NODE_XLATOR:
2528 				if (dtp->dt_xlatemode == DT_XL_DYNAMIC)
2529 					dt_compile_xlator(dnp);
2530 				break;
2531 			case DT_NODE_PROVIDER:
2532 				(void) dt_node_cook(dnp, DT_IDFLG_REF);
2533 				break;
2534 			}
2535 		}
2536 
2537 		yypcb->pcb_prog->dp_xrefs = yypcb->pcb_asxrefs;
2538 		yypcb->pcb_prog->dp_xrefslen = yypcb->pcb_asxreflen;
2539 		yypcb->pcb_asxrefs = NULL;
2540 		yypcb->pcb_asxreflen = 0;
2541 
2542 		rv = yypcb->pcb_prog;
2543 		break;
2544 
2545 	case DT_CTX_DEXPR:
2546 		(void) dt_node_cook(yypcb->pcb_root, DT_IDFLG_REF);
2547 		dt_cg(yypcb, yypcb->pcb_root);
2548 		rv = dt_as(yypcb);
2549 		break;
2550 
2551 	case DT_CTX_DTYPE:
2552 		ddp = (dt_decl_t *)yypcb->pcb_root; /* root is really a decl */
2553 		err = dt_decl_type(ddp, arg);
2554 		dt_decl_free(ddp);
2555 
2556 		if (err != 0)
2557 			longjmp(yypcb->pcb_jmpbuf, EDT_COMPILER);
2558 
2559 		rv = NULL;
2560 		break;
2561 	}
2562 
2563 out:
2564 	if (context != DT_CTX_DTYPE && yypcb->pcb_root != NULL &&
2565 	    DT_TREEDUMP_PASS(dtp, 3))
2566 		dt_node_printr(yypcb->pcb_root, stderr, 0);
2567 
2568 	if (dtp->dt_cdefs_fd != -1 && (ftruncate64(dtp->dt_cdefs_fd, 0) == -1 ||
2569 	    lseek64(dtp->dt_cdefs_fd, 0, SEEK_SET) == -1 ||
2570 	    ctf_write(dtp->dt_cdefs->dm_ctfp, dtp->dt_cdefs_fd) == CTF_ERR))
2571 		dt_dprintf("failed to update CTF cache: %s\n", strerror(errno));
2572 
2573 	if (dtp->dt_ddefs_fd != -1 && (ftruncate64(dtp->dt_ddefs_fd, 0) == -1 ||
2574 	    lseek64(dtp->dt_ddefs_fd, 0, SEEK_SET) == -1 ||
2575 	    ctf_write(dtp->dt_ddefs->dm_ctfp, dtp->dt_ddefs_fd) == CTF_ERR))
2576 		dt_dprintf("failed to update CTF cache: %s\n", strerror(errno));
2577 
2578 	if (yypcb->pcb_fileptr && (cflags & DTRACE_C_CPP))
2579 		(void) fclose(yypcb->pcb_fileptr); /* close dt_preproc() file */
2580 
2581 	dt_pcb_pop(dtp, err);
2582 	(void) dt_set_errno(dtp, err);
2583 	return (err ? NULL : rv);
2584 }
2585 
2586 dtrace_prog_t *
2587 dtrace_program_strcompile(dtrace_hdl_t *dtp, const char *s,
2588     dtrace_probespec_t spec, uint_t cflags, int argc, char *const argv[])
2589 {
2590 	return (dt_compile(dtp, DT_CTX_DPROG,
2591 	    spec, NULL, cflags, argc, argv, NULL, s));
2592 }
2593 
2594 dtrace_prog_t *
2595 dtrace_program_fcompile(dtrace_hdl_t *dtp, FILE *fp,
2596     uint_t cflags, int argc, char *const argv[])
2597 {
2598 	return (dt_compile(dtp, DT_CTX_DPROG,
2599 	    DTRACE_PROBESPEC_NAME, NULL, cflags, argc, argv, fp, NULL));
2600 }
2601 
2602 int
2603 dtrace_type_strcompile(dtrace_hdl_t *dtp, const char *s, dtrace_typeinfo_t *dtt)
2604 {
2605 	(void) dt_compile(dtp, DT_CTX_DTYPE,
2606 	    DTRACE_PROBESPEC_NONE, dtt, 0, 0, NULL, NULL, s);
2607 	return (dtp->dt_errno ? -1 : 0);
2608 }
2609 
2610 int
2611 dtrace_type_fcompile(dtrace_hdl_t *dtp, FILE *fp, dtrace_typeinfo_t *dtt)
2612 {
2613 	(void) dt_compile(dtp, DT_CTX_DTYPE,
2614 	    DTRACE_PROBESPEC_NONE, dtt, 0, 0, NULL, fp, NULL);
2615 	return (dtp->dt_errno ? -1 : 0);
2616 }
2617