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867e359b CM |
1 | /* |
2 | * Copyright 2010 Tilera Corporation. All Rights Reserved. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public License | |
6 | * as published by the Free Software Foundation, version 2. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, but | |
9 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or | |
11 | * NON INFRINGEMENT. See the GNU General Public License for | |
12 | * more details. | |
13 | */ | |
14 | ||
15 | #include <linux/kernel.h> | |
16 | #include <linux/string.h> | |
17 | ||
18 | #include <asm/backtrace.h> | |
19 | ||
20 | #include <arch/chip.h> | |
21 | ||
22 | #if TILE_CHIP < 10 | |
23 | ||
24 | ||
25 | #include <asm/opcode-tile.h> | |
26 | ||
27 | ||
28 | #define TREG_SP 54 | |
29 | #define TREG_LR 55 | |
30 | ||
31 | ||
32 | /** A decoded bundle used for backtracer analysis. */ | |
0707ad30 | 33 | struct BacktraceBundle { |
867e359b CM |
34 | tile_bundle_bits bits; |
35 | int num_insns; | |
36 | struct tile_decoded_instruction | |
37 | insns[TILE_MAX_INSTRUCTIONS_PER_BUNDLE]; | |
0707ad30 | 38 | }; |
867e359b CM |
39 | |
40 | ||
41 | /* This implementation only makes sense for native tools. */ | |
42 | /** Default function to read memory. */ | |
0707ad30 CM |
43 | static bool bt_read_memory(void *result, VirtualAddress addr, |
44 | size_t size, void *extra) | |
867e359b CM |
45 | { |
46 | /* FIXME: this should do some horrible signal stuff to catch | |
47 | * SEGV cleanly and fail. | |
48 | * | |
49 | * Or else the caller should do the setjmp for efficiency. | |
50 | */ | |
51 | ||
52 | memcpy(result, (const void *)addr, size); | |
53 | return true; | |
54 | } | |
55 | ||
56 | ||
57 | /** Locates an instruction inside the given bundle that | |
58 | * has the specified mnemonic, and whose first 'num_operands_to_match' | |
59 | * operands exactly match those in 'operand_values'. | |
60 | */ | |
0707ad30 CM |
61 | static const struct tile_decoded_instruction *find_matching_insn( |
62 | const struct BacktraceBundle *bundle, | |
63 | tile_mnemonic mnemonic, | |
64 | const int *operand_values, | |
65 | int num_operands_to_match) | |
867e359b CM |
66 | { |
67 | int i, j; | |
68 | bool match; | |
69 | ||
70 | for (i = 0; i < bundle->num_insns; i++) { | |
71 | const struct tile_decoded_instruction *insn = | |
72 | &bundle->insns[i]; | |
73 | ||
74 | if (insn->opcode->mnemonic != mnemonic) | |
75 | continue; | |
76 | ||
77 | match = true; | |
78 | for (j = 0; j < num_operands_to_match; j++) { | |
79 | if (operand_values[j] != insn->operand_values[j]) { | |
80 | match = false; | |
81 | break; | |
82 | } | |
83 | } | |
84 | ||
85 | if (match) | |
86 | return insn; | |
87 | } | |
88 | ||
89 | return NULL; | |
90 | } | |
91 | ||
92 | /** Does this bundle contain an 'iret' instruction? */ | |
0707ad30 | 93 | static inline bool bt_has_iret(const struct BacktraceBundle *bundle) |
867e359b CM |
94 | { |
95 | return find_matching_insn(bundle, TILE_OPC_IRET, NULL, 0) != NULL; | |
96 | } | |
97 | ||
98 | /** Does this bundle contain an 'addi sp, sp, OFFSET' or | |
99 | * 'addli sp, sp, OFFSET' instruction, and if so, what is OFFSET? | |
100 | */ | |
0707ad30 | 101 | static bool bt_has_addi_sp(const struct BacktraceBundle *bundle, int *adjust) |
867e359b CM |
102 | { |
103 | static const int vals[2] = { TREG_SP, TREG_SP }; | |
104 | ||
105 | const struct tile_decoded_instruction *insn = | |
106 | find_matching_insn(bundle, TILE_OPC_ADDI, vals, 2); | |
107 | if (insn == NULL) | |
108 | insn = find_matching_insn(bundle, TILE_OPC_ADDLI, vals, 2); | |
109 | if (insn == NULL) | |
110 | return false; | |
111 | ||
112 | *adjust = insn->operand_values[2]; | |
113 | return true; | |
114 | } | |
115 | ||
116 | /** Does this bundle contain any 'info OP' or 'infol OP' | |
117 | * instruction, and if so, what are their OP? Note that OP is interpreted | |
118 | * as an unsigned value by this code since that's what the caller wants. | |
119 | * Returns the number of info ops found. | |
120 | */ | |
0707ad30 | 121 | static int bt_get_info_ops(const struct BacktraceBundle *bundle, |
867e359b CM |
122 | int operands[MAX_INFO_OPS_PER_BUNDLE]) |
123 | { | |
124 | int num_ops = 0; | |
125 | int i; | |
126 | ||
127 | for (i = 0; i < bundle->num_insns; i++) { | |
128 | const struct tile_decoded_instruction *insn = | |
129 | &bundle->insns[i]; | |
130 | ||
131 | if (insn->opcode->mnemonic == TILE_OPC_INFO || | |
132 | insn->opcode->mnemonic == TILE_OPC_INFOL) { | |
133 | operands[num_ops++] = insn->operand_values[0]; | |
134 | } | |
135 | } | |
136 | ||
137 | return num_ops; | |
138 | } | |
139 | ||
140 | /** Does this bundle contain a jrp instruction, and if so, to which | |
141 | * register is it jumping? | |
142 | */ | |
0707ad30 | 143 | static bool bt_has_jrp(const struct BacktraceBundle *bundle, int *target_reg) |
867e359b CM |
144 | { |
145 | const struct tile_decoded_instruction *insn = | |
146 | find_matching_insn(bundle, TILE_OPC_JRP, NULL, 0); | |
147 | if (insn == NULL) | |
148 | return false; | |
149 | ||
150 | *target_reg = insn->operand_values[0]; | |
151 | return true; | |
152 | } | |
153 | ||
154 | /** Does this bundle modify the specified register in any way? */ | |
0707ad30 | 155 | static bool bt_modifies_reg(const struct BacktraceBundle *bundle, int reg) |
867e359b CM |
156 | { |
157 | int i, j; | |
158 | for (i = 0; i < bundle->num_insns; i++) { | |
159 | const struct tile_decoded_instruction *insn = | |
160 | &bundle->insns[i]; | |
161 | ||
162 | if (insn->opcode->implicitly_written_register == reg) | |
163 | return true; | |
164 | ||
165 | for (j = 0; j < insn->opcode->num_operands; j++) | |
166 | if (insn->operands[j]->is_dest_reg && | |
167 | insn->operand_values[j] == reg) | |
168 | return true; | |
169 | } | |
170 | ||
171 | return false; | |
172 | } | |
173 | ||
174 | /** Does this bundle modify sp? */ | |
0707ad30 | 175 | static inline bool bt_modifies_sp(const struct BacktraceBundle *bundle) |
867e359b CM |
176 | { |
177 | return bt_modifies_reg(bundle, TREG_SP); | |
178 | } | |
179 | ||
180 | /** Does this bundle modify lr? */ | |
0707ad30 | 181 | static inline bool bt_modifies_lr(const struct BacktraceBundle *bundle) |
867e359b CM |
182 | { |
183 | return bt_modifies_reg(bundle, TREG_LR); | |
184 | } | |
185 | ||
186 | /** Does this bundle contain the instruction 'move fp, sp'? */ | |
0707ad30 | 187 | static inline bool bt_has_move_r52_sp(const struct BacktraceBundle *bundle) |
867e359b CM |
188 | { |
189 | static const int vals[2] = { 52, TREG_SP }; | |
190 | return find_matching_insn(bundle, TILE_OPC_MOVE, vals, 2) != NULL; | |
191 | } | |
192 | ||
193 | /** Does this bundle contain the instruction 'sw sp, lr'? */ | |
0707ad30 | 194 | static inline bool bt_has_sw_sp_lr(const struct BacktraceBundle *bundle) |
867e359b CM |
195 | { |
196 | static const int vals[2] = { TREG_SP, TREG_LR }; | |
197 | return find_matching_insn(bundle, TILE_OPC_SW, vals, 2) != NULL; | |
198 | } | |
199 | ||
200 | /** Locates the caller's PC and SP for a program starting at the | |
201 | * given address. | |
202 | */ | |
0707ad30 CM |
203 | static void find_caller_pc_and_caller_sp(CallerLocation *location, |
204 | const VirtualAddress start_pc, | |
205 | BacktraceMemoryReader read_memory_func, | |
206 | void *read_memory_func_extra) | |
867e359b CM |
207 | { |
208 | /* Have we explicitly decided what the sp is, | |
209 | * rather than just the default? | |
210 | */ | |
211 | bool sp_determined = false; | |
212 | ||
213 | /* Has any bundle seen so far modified lr? */ | |
214 | bool lr_modified = false; | |
215 | ||
216 | /* Have we seen a move from sp to fp? */ | |
217 | bool sp_moved_to_r52 = false; | |
218 | ||
219 | /* Have we seen a terminating bundle? */ | |
220 | bool seen_terminating_bundle = false; | |
221 | ||
222 | /* Cut down on round-trip reading overhead by reading several | |
223 | * bundles at a time. | |
224 | */ | |
225 | tile_bundle_bits prefetched_bundles[32]; | |
226 | int num_bundles_prefetched = 0; | |
227 | int next_bundle = 0; | |
228 | VirtualAddress pc; | |
229 | ||
230 | /* Default to assuming that the caller's sp is the current sp. | |
231 | * This is necessary to handle the case where we start backtracing | |
232 | * right at the end of the epilog. | |
233 | */ | |
234 | location->sp_location = SP_LOC_OFFSET; | |
235 | location->sp_offset = 0; | |
236 | ||
237 | /* Default to having no idea where the caller PC is. */ | |
238 | location->pc_location = PC_LOC_UNKNOWN; | |
239 | ||
240 | /* Don't even try if the PC is not aligned. */ | |
241 | if (start_pc % TILE_BUNDLE_ALIGNMENT_IN_BYTES != 0) | |
242 | return; | |
243 | ||
244 | for (pc = start_pc;; pc += sizeof(tile_bundle_bits)) { | |
245 | ||
0707ad30 | 246 | struct BacktraceBundle bundle; |
867e359b CM |
247 | int num_info_ops, info_operands[MAX_INFO_OPS_PER_BUNDLE]; |
248 | int one_ago, jrp_reg; | |
249 | bool has_jrp; | |
250 | ||
251 | if (next_bundle >= num_bundles_prefetched) { | |
252 | /* Prefetch some bytes, but don't cross a page | |
253 | * boundary since that might cause a read failure we | |
254 | * don't care about if we only need the first few | |
255 | * bytes. Note: we don't care what the actual page | |
256 | * size is; using the minimum possible page size will | |
257 | * prevent any problems. | |
258 | */ | |
259 | unsigned int bytes_to_prefetch = 4096 - (pc & 4095); | |
260 | if (bytes_to_prefetch > sizeof prefetched_bundles) | |
261 | bytes_to_prefetch = sizeof prefetched_bundles; | |
262 | ||
263 | if (!read_memory_func(prefetched_bundles, pc, | |
264 | bytes_to_prefetch, | |
265 | read_memory_func_extra)) { | |
266 | if (pc == start_pc) { | |
267 | /* The program probably called a bad | |
268 | * address, such as a NULL pointer. | |
269 | * So treat this as if we are at the | |
270 | * start of the function prolog so the | |
271 | * backtrace will show how we got here. | |
272 | */ | |
273 | location->pc_location = PC_LOC_IN_LR; | |
274 | return; | |
275 | } | |
276 | ||
277 | /* Unreadable address. Give up. */ | |
278 | break; | |
279 | } | |
280 | ||
281 | next_bundle = 0; | |
282 | num_bundles_prefetched = | |
283 | bytes_to_prefetch / sizeof(tile_bundle_bits); | |
284 | } | |
285 | ||
286 | /* Decode the next bundle. */ | |
287 | bundle.bits = prefetched_bundles[next_bundle++]; | |
288 | bundle.num_insns = | |
289 | parse_insn_tile(bundle.bits, pc, bundle.insns); | |
290 | num_info_ops = bt_get_info_ops(&bundle, info_operands); | |
291 | ||
292 | /* First look at any one_ago info ops if they are interesting, | |
293 | * since they should shadow any non-one-ago info ops. | |
294 | */ | |
295 | for (one_ago = (pc != start_pc) ? 1 : 0; | |
296 | one_ago >= 0; one_ago--) { | |
297 | int i; | |
298 | for (i = 0; i < num_info_ops; i++) { | |
299 | int info_operand = info_operands[i]; | |
300 | if (info_operand < CALLER_UNKNOWN_BASE) { | |
301 | /* Weird; reserved value, ignore it. */ | |
302 | continue; | |
303 | } | |
304 | ||
305 | /* Skip info ops which are not in the | |
306 | * "one_ago" mode we want right now. | |
307 | */ | |
308 | if (((info_operand & ONE_BUNDLE_AGO_FLAG) != 0) | |
309 | != (one_ago != 0)) | |
310 | continue; | |
311 | ||
312 | /* Clear the flag to make later checking | |
313 | * easier. */ | |
314 | info_operand &= ~ONE_BUNDLE_AGO_FLAG; | |
315 | ||
316 | /* Default to looking at PC_IN_LR_FLAG. */ | |
317 | if (info_operand & PC_IN_LR_FLAG) | |
318 | location->pc_location = | |
319 | PC_LOC_IN_LR; | |
320 | else | |
321 | location->pc_location = | |
322 | PC_LOC_ON_STACK; | |
323 | ||
324 | switch (info_operand) { | |
325 | case CALLER_UNKNOWN_BASE: | |
326 | location->pc_location = PC_LOC_UNKNOWN; | |
327 | location->sp_location = SP_LOC_UNKNOWN; | |
328 | return; | |
329 | ||
330 | case CALLER_SP_IN_R52_BASE: | |
331 | case CALLER_SP_IN_R52_BASE | PC_IN_LR_FLAG: | |
332 | location->sp_location = SP_LOC_IN_R52; | |
333 | return; | |
334 | ||
335 | default: | |
336 | { | |
337 | const unsigned int val = info_operand | |
338 | - CALLER_SP_OFFSET_BASE; | |
339 | const unsigned int sp_offset = | |
340 | (val >> NUM_INFO_OP_FLAGS) * 8; | |
341 | if (sp_offset < 32768) { | |
342 | /* This is a properly encoded | |
343 | * SP offset. */ | |
344 | location->sp_location = | |
345 | SP_LOC_OFFSET; | |
346 | location->sp_offset = | |
347 | sp_offset; | |
348 | return; | |
349 | } else { | |
350 | /* This looked like an SP | |
351 | * offset, but it's outside | |
352 | * the legal range, so this | |
353 | * must be an unrecognized | |
354 | * info operand. Ignore it. | |
355 | */ | |
356 | } | |
357 | } | |
358 | break; | |
359 | } | |
360 | } | |
361 | } | |
362 | ||
363 | if (seen_terminating_bundle) { | |
364 | /* We saw a terminating bundle during the previous | |
365 | * iteration, so we were only looking for an info op. | |
366 | */ | |
367 | break; | |
368 | } | |
369 | ||
370 | if (bundle.bits == 0) { | |
371 | /* Wacky terminating bundle. Stop looping, and hope | |
372 | * we've already seen enough to find the caller. | |
373 | */ | |
374 | break; | |
375 | } | |
376 | ||
377 | /* | |
378 | * Try to determine caller's SP. | |
379 | */ | |
380 | ||
381 | if (!sp_determined) { | |
382 | int adjust; | |
383 | if (bt_has_addi_sp(&bundle, &adjust)) { | |
384 | location->sp_location = SP_LOC_OFFSET; | |
385 | ||
386 | if (adjust <= 0) { | |
387 | /* We are in prolog about to adjust | |
388 | * SP. */ | |
389 | location->sp_offset = 0; | |
390 | } else { | |
391 | /* We are in epilog restoring SP. */ | |
392 | location->sp_offset = adjust; | |
393 | } | |
394 | ||
395 | sp_determined = true; | |
396 | } else { | |
397 | if (bt_has_move_r52_sp(&bundle)) { | |
398 | /* Maybe in prolog, creating an | |
399 | * alloca-style frame. But maybe in | |
400 | * the middle of a fixed-size frame | |
401 | * clobbering r52 with SP. | |
402 | */ | |
403 | sp_moved_to_r52 = true; | |
404 | } | |
405 | ||
406 | if (bt_modifies_sp(&bundle)) { | |
407 | if (sp_moved_to_r52) { | |
408 | /* We saw SP get saved into | |
409 | * r52 earlier (or now), which | |
410 | * must have been in the | |
411 | * prolog, so we now know that | |
412 | * SP is still holding the | |
413 | * caller's sp value. | |
414 | */ | |
415 | location->sp_location = | |
416 | SP_LOC_OFFSET; | |
417 | location->sp_offset = 0; | |
418 | } else { | |
419 | /* Someone must have saved | |
420 | * aside the caller's SP value | |
421 | * into r52, so r52 holds the | |
422 | * current value. | |
423 | */ | |
424 | location->sp_location = | |
425 | SP_LOC_IN_R52; | |
426 | } | |
427 | sp_determined = true; | |
428 | } | |
429 | } | |
430 | } | |
431 | ||
432 | if (bt_has_iret(&bundle)) { | |
433 | /* This is a terminating bundle. */ | |
434 | seen_terminating_bundle = true; | |
435 | continue; | |
436 | } | |
437 | ||
438 | /* | |
439 | * Try to determine caller's PC. | |
440 | */ | |
441 | ||
442 | jrp_reg = -1; | |
443 | has_jrp = bt_has_jrp(&bundle, &jrp_reg); | |
444 | if (has_jrp) | |
445 | seen_terminating_bundle = true; | |
446 | ||
447 | if (location->pc_location == PC_LOC_UNKNOWN) { | |
448 | if (has_jrp) { | |
449 | if (jrp_reg == TREG_LR && !lr_modified) { | |
450 | /* Looks like a leaf function, or else | |
451 | * lr is already restored. */ | |
452 | location->pc_location = | |
453 | PC_LOC_IN_LR; | |
454 | } else { | |
455 | location->pc_location = | |
456 | PC_LOC_ON_STACK; | |
457 | } | |
458 | } else if (bt_has_sw_sp_lr(&bundle)) { | |
459 | /* In prolog, spilling initial lr to stack. */ | |
460 | location->pc_location = PC_LOC_IN_LR; | |
461 | } else if (bt_modifies_lr(&bundle)) { | |
462 | lr_modified = true; | |
463 | } | |
464 | } | |
465 | } | |
466 | } | |
467 | ||
0707ad30 CM |
468 | void backtrace_init(BacktraceIterator *state, |
469 | BacktraceMemoryReader read_memory_func, | |
470 | void *read_memory_func_extra, | |
471 | VirtualAddress pc, VirtualAddress lr, | |
472 | VirtualAddress sp, VirtualAddress r52) | |
867e359b CM |
473 | { |
474 | CallerLocation location; | |
475 | VirtualAddress fp, initial_frame_caller_pc; | |
476 | ||
477 | if (read_memory_func == NULL) { | |
478 | read_memory_func = bt_read_memory; | |
479 | } | |
480 | ||
481 | /* Find out where we are in the initial frame. */ | |
482 | find_caller_pc_and_caller_sp(&location, pc, | |
483 | read_memory_func, read_memory_func_extra); | |
484 | ||
485 | switch (location.sp_location) { | |
486 | case SP_LOC_UNKNOWN: | |
487 | /* Give up. */ | |
488 | fp = -1; | |
489 | break; | |
490 | ||
491 | case SP_LOC_IN_R52: | |
492 | fp = r52; | |
493 | break; | |
494 | ||
495 | case SP_LOC_OFFSET: | |
496 | fp = sp + location.sp_offset; | |
497 | break; | |
498 | ||
499 | default: | |
500 | /* Give up. */ | |
501 | fp = -1; | |
502 | break; | |
503 | } | |
504 | ||
505 | /* The frame pointer should theoretically be aligned mod 8. If | |
506 | * it's not even aligned mod 4 then something terrible happened | |
507 | * and we should mark it as invalid. | |
508 | */ | |
509 | if (fp % 4 != 0) | |
510 | fp = -1; | |
511 | ||
512 | /* -1 means "don't know initial_frame_caller_pc". */ | |
513 | initial_frame_caller_pc = -1; | |
514 | ||
515 | switch (location.pc_location) { | |
516 | case PC_LOC_UNKNOWN: | |
517 | /* Give up. */ | |
518 | fp = -1; | |
519 | break; | |
520 | ||
521 | case PC_LOC_IN_LR: | |
522 | if (lr == 0 || lr % TILE_BUNDLE_ALIGNMENT_IN_BYTES != 0) { | |
523 | /* Give up. */ | |
524 | fp = -1; | |
525 | } else { | |
526 | initial_frame_caller_pc = lr; | |
527 | } | |
528 | break; | |
529 | ||
530 | case PC_LOC_ON_STACK: | |
531 | /* Leave initial_frame_caller_pc as -1, | |
532 | * meaning check the stack. | |
533 | */ | |
534 | break; | |
535 | ||
536 | default: | |
537 | /* Give up. */ | |
538 | fp = -1; | |
539 | break; | |
540 | } | |
541 | ||
542 | state->pc = pc; | |
543 | state->sp = sp; | |
544 | state->fp = fp; | |
545 | state->initial_frame_caller_pc = initial_frame_caller_pc; | |
546 | state->read_memory_func = read_memory_func; | |
547 | state->read_memory_func_extra = read_memory_func_extra; | |
548 | } | |
549 | ||
0707ad30 | 550 | bool backtrace_next(BacktraceIterator *state) |
867e359b CM |
551 | { |
552 | VirtualAddress next_fp, next_pc, next_frame[2]; | |
553 | ||
554 | if (state->fp == -1) { | |
555 | /* No parent frame. */ | |
556 | return false; | |
557 | } | |
558 | ||
559 | /* Try to read the frame linkage data chaining to the next function. */ | |
560 | if (!state->read_memory_func(&next_frame, state->fp, sizeof next_frame, | |
561 | state->read_memory_func_extra)) { | |
562 | return false; | |
563 | } | |
564 | ||
565 | next_fp = next_frame[1]; | |
566 | if (next_fp % 4 != 0) { | |
567 | /* Caller's frame pointer is suspect, so give up. | |
568 | * Technically it should be aligned mod 8, but we will | |
569 | * be forgiving here. | |
570 | */ | |
571 | return false; | |
572 | } | |
573 | ||
574 | if (state->initial_frame_caller_pc != -1) { | |
575 | /* We must be in the initial stack frame and already know the | |
576 | * caller PC. | |
577 | */ | |
578 | next_pc = state->initial_frame_caller_pc; | |
579 | ||
580 | /* Force reading stack next time, in case we were in the | |
581 | * initial frame. We don't do this above just to paranoidly | |
582 | * avoid changing the struct at all when we return false. | |
583 | */ | |
584 | state->initial_frame_caller_pc = -1; | |
585 | } else { | |
586 | /* Get the caller PC from the frame linkage area. */ | |
587 | next_pc = next_frame[0]; | |
588 | if (next_pc == 0 || | |
589 | next_pc % TILE_BUNDLE_ALIGNMENT_IN_BYTES != 0) { | |
590 | /* The PC is suspect, so give up. */ | |
591 | return false; | |
592 | } | |
593 | } | |
594 | ||
595 | /* Update state to become the caller's stack frame. */ | |
596 | state->pc = next_pc; | |
597 | state->sp = state->fp; | |
598 | state->fp = next_fp; | |
599 | ||
600 | return true; | |
601 | } | |
602 | ||
603 | #else /* TILE_CHIP < 10 */ | |
604 | ||
0707ad30 CM |
605 | void backtrace_init(BacktraceIterator *state, |
606 | BacktraceMemoryReader read_memory_func, | |
607 | void *read_memory_func_extra, | |
608 | VirtualAddress pc, VirtualAddress lr, | |
609 | VirtualAddress sp, VirtualAddress r52) | |
867e359b CM |
610 | { |
611 | state->pc = pc; | |
612 | state->sp = sp; | |
613 | state->fp = -1; | |
614 | state->initial_frame_caller_pc = -1; | |
615 | state->read_memory_func = read_memory_func; | |
616 | state->read_memory_func_extra = read_memory_func_extra; | |
617 | } | |
618 | ||
619 | bool backtrace_next(BacktraceIterator *state) { return false; } | |
620 | ||
621 | #endif /* TILE_CHIP < 10 */ |