xref: /titanic_44/usr/src/lib/libdtrace/common/dt_as.c (revision 8eea8e29cc4374d1ee24c25a07f45af132db3499)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/types.h>
30 #include <strings.h>
31 #include <stdlib.h>
32 #include <assert.h>
33 
34 #include <dt_impl.h>
35 #include <dt_parser.h>
36 #include <dt_as.h>
37 
38 void
39 dt_irlist_create(dt_irlist_t *dlp)
40 {
41 	bzero(dlp, sizeof (dt_irlist_t));
42 	dlp->dl_label = 1;
43 }
44 
45 void
46 dt_irlist_destroy(dt_irlist_t *dlp)
47 {
48 	dt_irnode_t *dip, *nip;
49 
50 	for (dip = dlp->dl_list; dip != NULL; dip = nip) {
51 		nip = dip->di_next;
52 		free(dip);
53 	}
54 }
55 
56 void
57 dt_irlist_append(dt_irlist_t *dlp, dt_irnode_t *dip)
58 {
59 	if (dlp->dl_last != NULL)
60 		dlp->dl_last->di_next = dip;
61 	else
62 		dlp->dl_list = dip;
63 
64 	dlp->dl_last = dip;
65 
66 	if (dip->di_label == DT_LBL_NONE || dip->di_instr != DIF_INSTR_NOP)
67 		dlp->dl_len++; /* don't count forward refs in instr count */
68 }
69 
70 uint_t
71 dt_irlist_label(dt_irlist_t *dlp)
72 {
73 	return (dlp->dl_label++);
74 }
75 
76 /*ARGSUSED*/
77 static int
78 dt_countvar(dt_idhash_t *dhp, dt_ident_t *idp, void *data)
79 {
80 	size_t *np = data;
81 
82 	if (idp->di_flags & (DT_IDFLG_DIFR | DT_IDFLG_DIFW))
83 		(*np)++; /* include variable in vartab */
84 
85 	return (0);
86 }
87 
88 /*ARGSUSED*/
89 static int
90 dt_copyvar(dt_idhash_t *dhp, dt_ident_t *idp, void *data)
91 {
92 	dt_pcb_t *pcb = data;
93 	dtrace_difv_t *dvp;
94 	ssize_t stroff;
95 	dt_node_t dn;
96 
97 	if (!(idp->di_flags & (DT_IDFLG_DIFR | DT_IDFLG_DIFW)))
98 		return (0); /* omit variable from vartab */
99 
100 	dvp = &pcb->pcb_difo->dtdo_vartab[pcb->pcb_asvidx++];
101 	stroff = dt_strtab_insert(pcb->pcb_strtab, idp->di_name);
102 
103 	if (stroff == -1L)
104 		longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
105 	if (stroff > DIF_STROFF_MAX)
106 		longjmp(pcb->pcb_jmpbuf, EDT_STR2BIG);
107 
108 	dvp->dtdv_name = (uint_t)stroff;
109 	dvp->dtdv_id = idp->di_id;
110 	dvp->dtdv_flags = 0;
111 
112 	dvp->dtdv_kind = (idp->di_kind == DT_IDENT_ARRAY) ?
113 	    DIFV_KIND_ARRAY : DIFV_KIND_SCALAR;
114 
115 	if (idp->di_flags & DT_IDFLG_LOCAL)
116 		dvp->dtdv_scope = DIFV_SCOPE_LOCAL;
117 	else if (idp->di_flags & DT_IDFLG_TLS)
118 		dvp->dtdv_scope = DIFV_SCOPE_THREAD;
119 	else
120 		dvp->dtdv_scope = DIFV_SCOPE_GLOBAL;
121 
122 	if (idp->di_flags & DT_IDFLG_DIFR)
123 		dvp->dtdv_flags |= DIFV_F_REF;
124 	if (idp->di_flags & DT_IDFLG_DIFW)
125 		dvp->dtdv_flags |= DIFV_F_MOD;
126 
127 	bzero(&dn, sizeof (dn));
128 	dt_node_type_assign(&dn, idp->di_ctfp, idp->di_type);
129 	dt_node_diftype(&dn, &dvp->dtdv_type);
130 
131 	idp->di_flags &= ~(DT_IDFLG_DIFR | DT_IDFLG_DIFW);
132 	return (0);
133 }
134 
135 static ssize_t
136 dt_copystr(const char *s, size_t n, size_t off, dt_pcb_t *pcb)
137 {
138 	bcopy(s, pcb->pcb_difo->dtdo_strtab + off, n);
139 	return (n);
140 }
141 
142 static void
143 dt_as_undef(const dt_ident_t *idp, uint_t offset)
144 {
145 	const char *kind, *mark = (idp->di_flags & DT_IDFLG_USER) ? "``" : "`";
146 	const dtrace_syminfo_t *dts = idp->di_data;
147 
148 	if (idp->di_flags & DT_IDFLG_USER)
149 		kind = "user";
150 	else if (idp->di_flags & DT_IDFLG_PRIM)
151 		kind = "primary kernel";
152 	else
153 		kind = "loadable kernel";
154 
155 	yylineno = idp->di_lineno;
156 
157 	xyerror(D_ASRELO, "relocation remains against %s symbol %s%s%s (offset "
158 	    "0x%x)\n", kind, dts->dts_object, mark, dts->dts_name, offset);
159 }
160 
161 dtrace_difo_t *
162 dt_as(dt_pcb_t *pcb)
163 {
164 	dtrace_hdl_t *dtp = pcb->pcb_hdl;
165 	dt_irlist_t *dlp = &pcb->pcb_ir;
166 	uint_t *labels = NULL;
167 	dt_irnode_t *dip;
168 	dtrace_difo_t *dp;
169 	dt_ident_t *idp;
170 
171 	size_t n = 0;
172 	uint_t i;
173 
174 	uint_t kmask, kbits, umask, ubits;
175 	uint_t krel = 0, urel = 0;
176 
177 	/*
178 	 * Select bitmasks based upon the desired symbol linking policy.  We
179 	 * test (di_ident->di_flags & xmask) == xbits to determine if the
180 	 * symbol should have a relocation entry generated in the loop below.
181 	 *
182 	 * DT_LINK_KERNEL = kernel symbols static, user symbols dynamic
183 	 * DT_LINK_PRIMARY = primary kernel symbols static, others dynamic
184 	 * DT_LINK_DYNAMIC = all symbols dynamic
185 	 * DT_LINK_STATIC = all symbols static
186 	 *
187 	 * By 'static' we mean that we use the symbol's value at compile-time
188 	 * in the final DIF.  By 'dynamic' we mean that we create a relocation
189 	 * table entry for the symbol's value so it can be relocated later.
190 	 */
191 	switch (dtp->dt_linkmode) {
192 	case DT_LINK_KERNEL:
193 		kmask = 0;
194 		kbits = -1u;
195 		umask = DT_IDFLG_USER;
196 		ubits = DT_IDFLG_USER;
197 		break;
198 	case DT_LINK_PRIMARY:
199 		kmask = DT_IDFLG_USER | DT_IDFLG_PRIM;
200 		kbits = 0;
201 		umask = DT_IDFLG_USER;
202 		ubits = DT_IDFLG_USER;
203 		break;
204 	case DT_LINK_DYNAMIC:
205 		kmask = DT_IDFLG_USER;
206 		kbits = 0;
207 		umask = DT_IDFLG_USER;
208 		ubits = DT_IDFLG_USER;
209 		break;
210 	case DT_LINK_STATIC:
211 		kmask = umask = 0;
212 		kbits = ubits = -1u;
213 		break;
214 	default:
215 		xyerror(D_UNKNOWN, "internal error -- invalid link mode %u\n",
216 		    dtp->dt_linkmode);
217 	}
218 
219 	if ((dp = malloc(sizeof (dtrace_difo_t))) == NULL)
220 		longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
221 
222 	assert(yypcb->pcb_difo == NULL);
223 	yypcb->pcb_difo = dp;
224 
225 	bzero(dp, sizeof (dtrace_difo_t));
226 	dp->dtdo_refcnt = 1;
227 	dp->dtdo_buf = malloc(sizeof (dif_instr_t) * dlp->dl_len);
228 
229 	if (dp->dtdo_buf == NULL)
230 		longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
231 
232 	if ((labels = malloc(sizeof (uint_t) * dlp->dl_label)) == NULL)
233 		longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
234 
235 	/*
236 	 * Make an initial pass through the instruction list, filling in the
237 	 * instruction buffer with valid instructions and skipping labeled nops.
238 	 * While doing this, we also fill in our labels[] translation table
239 	 * and we count up the number of relocation table entries we will need.
240 	 */
241 	for (i = 0, dip = dlp->dl_list; dip != NULL; dip = dip->di_next) {
242 		if (dip->di_label != DT_LBL_NONE)
243 			labels[dip->di_label] = i;
244 
245 		if (dip->di_label == DT_LBL_NONE ||
246 		    dip->di_instr != DIF_INSTR_NOP)
247 			dp->dtdo_buf[i++] = dip->di_instr;
248 
249 		if ((idp = dip->di_ident) == NULL)
250 			continue; /* no relocation entry needed */
251 
252 		if ((idp->di_flags & kmask) == kbits)
253 			krel++;
254 		else if ((idp->di_flags & umask) == ubits)
255 			urel++;
256 	}
257 
258 	assert(i == dlp->dl_len);
259 	dp->dtdo_len = dlp->dl_len;
260 
261 	/*
262 	 * Make a second pass through the instructions, relocating each branch
263 	 * label to the index of the final instruction in the buffer and noting
264 	 * any other instruction-specific DIFO flags such as dtdo_destructive.
265 	 */
266 	for (i = 0; i < dp->dtdo_len; i++) {
267 		dif_instr_t instr = dp->dtdo_buf[i];
268 		uint_t op = DIF_INSTR_OP(instr);
269 
270 		if (op == DIF_OP_CALL) {
271 			if (DIF_INSTR_SUBR(instr) == DIF_SUBR_COPYOUT ||
272 			    DIF_INSTR_SUBR(instr) == DIF_SUBR_COPYOUTSTR)
273 				dp->dtdo_destructive = 1;
274 			continue;
275 		}
276 
277 		if (op >= DIF_OP_BA && op <= DIF_OP_BLEU) {
278 			assert(DIF_INSTR_LABEL(instr) < dlp->dl_label);
279 			dp->dtdo_buf[i] = DIF_INSTR_BRANCH(op,
280 			    labels[DIF_INSTR_LABEL(instr)]);
281 		}
282 	}
283 
284 	free(labels);
285 	yypcb->pcb_asvidx = 0;
286 
287 	/*
288 	 * Allocate memory for the appropriate number of variable records and
289 	 * then fill in each variable record.  As we populate the variable
290 	 * table we insert the corresponding variable names into the strtab.
291 	 */
292 	(void) dt_idhash_iter(dtp->dt_tls, dt_countvar, &n);
293 	(void) dt_idhash_iter(dtp->dt_globals, dt_countvar, &n);
294 	(void) dt_idhash_iter(pcb->pcb_locals, dt_countvar, &n);
295 
296 	if (n != 0) {
297 		dp->dtdo_vartab = malloc(n * sizeof (dtrace_difv_t));
298 		dp->dtdo_varlen = (uint32_t)n;
299 
300 		if (dp->dtdo_vartab == NULL)
301 			longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
302 
303 		(void) dt_idhash_iter(dtp->dt_tls, dt_copyvar, pcb);
304 		(void) dt_idhash_iter(dtp->dt_globals, dt_copyvar, pcb);
305 		(void) dt_idhash_iter(pcb->pcb_locals, dt_copyvar, pcb);
306 	}
307 
308 	/*
309 	 * Allocate memory for the appropriate number of relocation table
310 	 * entries based upon our kernel and user counts from the first pass.
311 	 */
312 	if (krel != 0) {
313 		dp->dtdo_kreltab = malloc(krel * sizeof (dof_relodesc_t));
314 		dp->dtdo_krelen = krel;
315 
316 		if (dp->dtdo_kreltab == NULL)
317 			longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
318 	}
319 
320 	if (urel != 0) {
321 		dp->dtdo_ureltab = malloc(urel * sizeof (dof_relodesc_t));
322 		dp->dtdo_urelen = urel;
323 
324 		if (dp->dtdo_ureltab == NULL)
325 			longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
326 	}
327 
328 	/*
329 	 * If any relocations are needed, make another pass through the
330 	 * instruction list and fill in the relocation table entries.
331 	 */
332 	if (krel + urel != 0) {
333 		uint_t knodef = pcb->pcb_cflags & DTRACE_C_KNODEF;
334 		uint_t unodef = pcb->pcb_cflags & DTRACE_C_UNODEF;
335 
336 		dof_relodesc_t *krp = dp->dtdo_kreltab;
337 		dof_relodesc_t *urp = dp->dtdo_ureltab;
338 
339 		i = 0; /* dtdo_buf[] index */
340 
341 		for (dip = dlp->dl_list; dip != NULL; dip = dip->di_next) {
342 			dof_relodesc_t *rp;
343 			ssize_t soff;
344 			uint_t nodef;
345 
346 			if (dip->di_label != DT_LBL_NONE &&
347 			    dip->di_instr == DIF_INSTR_NOP)
348 				continue; /* skip label declarations */
349 
350 			i++; /* advance dtdo_buf[] index */
351 
352 			if ((idp = dip->di_ident) == NULL)
353 				continue; /* no relocation entry needed */
354 
355 			if ((idp->di_flags & kmask) == kbits) {
356 				nodef = knodef;
357 				rp = krp++;
358 			} else if ((idp->di_flags & umask) == ubits) {
359 				nodef = unodef;
360 				rp = urp++;
361 			} else
362 				continue;
363 
364 			if (!nodef)
365 				dt_as_undef(idp, i);
366 
367 			assert(DIF_INSTR_OP(dip->di_instr) == DIF_OP_SETX);
368 			soff = dt_strtab_insert(pcb->pcb_strtab, idp->di_name);
369 
370 			if (soff == -1L)
371 				longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
372 			if (soff > DIF_STROFF_MAX)
373 				longjmp(pcb->pcb_jmpbuf, EDT_STR2BIG);
374 
375 			rp->dofr_name = (dof_stridx_t)soff;
376 			rp->dofr_type = DOF_RELO_SETX;
377 			rp->dofr_offset = DIF_INSTR_INTEGER(dip->di_instr) *
378 			    sizeof (uint64_t);
379 			rp->dofr_data = 0;
380 		}
381 
382 		assert(krp == dp->dtdo_kreltab + dp->dtdo_krelen);
383 		assert(urp == dp->dtdo_ureltab + dp->dtdo_urelen);
384 		assert(i == dp->dtdo_len);
385 	}
386 
387 	/*
388 	 * Allocate memory for the compiled string table and then copy the
389 	 * chunks from the string table into the final string buffer.
390 	 */
391 	if ((n = dt_strtab_size(pcb->pcb_strtab)) != 0) {
392 		if ((dp->dtdo_strtab = malloc(n)) == NULL)
393 			longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
394 
395 		(void) dt_strtab_write(pcb->pcb_strtab,
396 		    (dt_strtab_write_f *)dt_copystr, pcb);
397 		dp->dtdo_strlen = (uint32_t)n;
398 	}
399 
400 	/*
401 	 * Allocate memory for the compiled integer table and then copy the
402 	 * integer constants from the table into the final integer buffer.
403 	 */
404 	if ((n = dt_inttab_size(pcb->pcb_inttab)) != 0) {
405 		if ((dp->dtdo_inttab = malloc(n * sizeof (uint64_t))) == NULL)
406 			longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
407 
408 		dt_inttab_write(pcb->pcb_inttab, dp->dtdo_inttab);
409 		dp->dtdo_intlen = (uint32_t)n;
410 	}
411 
412 	/*
413 	 * Fill in the DIFO return type from the type associated with the
414 	 * node saved in pcb_dret, and then clear pcb_difo and pcb_dret
415 	 * now that the assembler has completed successfully.
416 	 */
417 	dt_node_diftype(pcb->pcb_dret, &dp->dtdo_rtype);
418 	pcb->pcb_difo = NULL;
419 	pcb->pcb_dret = NULL;
420 
421 	if (pcb->pcb_cflags & DTRACE_C_DIFV)
422 		dtrace_difo_print(dp, stderr);
423 
424 	return (dp);
425 }
426