xref: /linux/tools/perf/util/annotate-data.c (revision 4fb7eefe6c539840fa8854d67d00af35331b8843)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Convert sample address to data type using DWARF debug info.
4  *
5  * Written by Namhyung Kim <namhyung@kernel.org>
6  */
7 #include <errno.h>
8 #include <stdio.h>
9 #include <stdlib.h>
10 #include <inttypes.h>
11 #include <linux/zalloc.h>
12 
13 #include "annotate.h"
14 #include "annotate-data.h"
15 #include "debuginfo.h"
16 #include "debug.h"
17 #include "dso.h"
18 #include "dwarf-regs.h"
19 #include "evsel.h"
20 #include "evlist.h"
21 #include "map.h"
22 #include "map_symbol.h"
23 #include "sort.h"
24 #include "strbuf.h"
25 #include "symbol.h"
26 #include "symbol_conf.h"
27 #include "thread.h"
28 
29 /* register number of the stack pointer */
30 #define X86_REG_SP 7
31 
32 static void delete_var_types(struct die_var_type *var_types);
33 
34 #define pr_debug_dtp(fmt, ...)					\
35 do {								\
36 	if (debug_type_profile)					\
37 		pr_info(fmt, ##__VA_ARGS__);			\
38 	else							\
39 		pr_debug3(fmt, ##__VA_ARGS__);			\
40 } while (0)
41 
42 void pr_debug_type_name(Dwarf_Die *die, enum type_state_kind kind)
43 {
44 	struct strbuf sb;
45 	char *str;
46 	Dwarf_Word size = 0;
47 
48 	if (!debug_type_profile && verbose < 3)
49 		return;
50 
51 	switch (kind) {
52 	case TSR_KIND_INVALID:
53 		pr_info("\n");
54 		return;
55 	case TSR_KIND_PERCPU_BASE:
56 		pr_info(" percpu base\n");
57 		return;
58 	case TSR_KIND_CONST:
59 		pr_info(" constant\n");
60 		return;
61 	case TSR_KIND_PERCPU_POINTER:
62 		pr_info(" percpu pointer");
63 		/* it also prints the type info */
64 		break;
65 	case TSR_KIND_POINTER:
66 		pr_info(" pointer");
67 		/* it also prints the type info */
68 		break;
69 	case TSR_KIND_CANARY:
70 		pr_info(" stack canary\n");
71 		return;
72 	case TSR_KIND_TYPE:
73 	default:
74 		break;
75 	}
76 
77 	dwarf_aggregate_size(die, &size);
78 
79 	strbuf_init(&sb, 32);
80 	die_get_typename_from_type(die, &sb);
81 	str = strbuf_detach(&sb, NULL);
82 	pr_info(" type='%s' size=%#lx (die:%#lx)\n",
83 		str, (long)size, (long)dwarf_dieoffset(die));
84 	free(str);
85 }
86 
87 static void pr_debug_location(Dwarf_Die *die, u64 pc, int reg)
88 {
89 	ptrdiff_t off = 0;
90 	Dwarf_Attribute attr;
91 	Dwarf_Addr base, start, end;
92 	Dwarf_Op *ops;
93 	size_t nops;
94 
95 	if (!debug_type_profile && verbose < 3)
96 		return;
97 
98 	if (dwarf_attr(die, DW_AT_location, &attr) == NULL)
99 		return;
100 
101 	while ((off = dwarf_getlocations(&attr, off, &base, &start, &end, &ops, &nops)) > 0) {
102 		if (reg != DWARF_REG_PC && end <= pc)
103 			continue;
104 		if (reg != DWARF_REG_PC && start > pc)
105 			break;
106 
107 		pr_info(" variable location: ");
108 		switch (ops->atom) {
109 		case DW_OP_reg0 ...DW_OP_reg31:
110 			pr_info("reg%d\n", ops->atom - DW_OP_reg0);
111 			break;
112 		case DW_OP_breg0 ...DW_OP_breg31:
113 			pr_info("base=reg%d, offset=%#lx\n",
114 				ops->atom - DW_OP_breg0, (long)ops->number);
115 			break;
116 		case DW_OP_regx:
117 			pr_info("reg%ld\n", (long)ops->number);
118 			break;
119 		case DW_OP_bregx:
120 			pr_info("base=reg%ld, offset=%#lx\n",
121 				(long)ops->number, (long)ops->number2);
122 			break;
123 		case DW_OP_fbreg:
124 			pr_info("use frame base, offset=%#lx\n", (long)ops->number);
125 			break;
126 		case DW_OP_addr:
127 			pr_info("address=%#lx\n", (long)ops->number);
128 			break;
129 		default:
130 			pr_info("unknown: code=%#x, number=%#lx\n",
131 				ops->atom, (long)ops->number);
132 			break;
133 		}
134 		break;
135 	}
136 }
137 
138 static void pr_debug_scope(Dwarf_Die *scope_die)
139 {
140 	int tag;
141 
142 	if (!debug_type_profile && verbose < 3)
143 		return;
144 
145 	pr_info("(die:%lx) ", (long)dwarf_dieoffset(scope_die));
146 
147 	tag = dwarf_tag(scope_die);
148 	if (tag == DW_TAG_subprogram)
149 		pr_info("[function] %s\n", dwarf_diename(scope_die));
150 	else if (tag == DW_TAG_inlined_subroutine)
151 		pr_info("[inlined] %s\n", dwarf_diename(scope_die));
152 	else if (tag == DW_TAG_lexical_block)
153 		pr_info("[block]\n");
154 	else
155 		pr_info("[unknown] tag=%x\n", tag);
156 }
157 
158 bool has_reg_type(struct type_state *state, int reg)
159 {
160 	return (unsigned)reg < ARRAY_SIZE(state->regs);
161 }
162 
163 static void init_type_state(struct type_state *state, const struct arch *arch)
164 {
165 	memset(state, 0, sizeof(*state));
166 	INIT_LIST_HEAD(&state->stack_vars);
167 
168 	if (arch__is_x86(arch)) {
169 		state->regs[0].caller_saved = true;
170 		state->regs[1].caller_saved = true;
171 		state->regs[2].caller_saved = true;
172 		state->regs[4].caller_saved = true;
173 		state->regs[5].caller_saved = true;
174 		state->regs[8].caller_saved = true;
175 		state->regs[9].caller_saved = true;
176 		state->regs[10].caller_saved = true;
177 		state->regs[11].caller_saved = true;
178 		state->ret_reg = 0;
179 		state->stack_reg = X86_REG_SP;
180 	}
181 }
182 
183 static void exit_type_state(struct type_state *state)
184 {
185 	struct type_state_stack *stack, *tmp;
186 
187 	list_for_each_entry_safe(stack, tmp, &state->stack_vars, list) {
188 		list_del(&stack->list);
189 		free(stack);
190 	}
191 }
192 
193 /*
194  * Compare type name and size to maintain them in a tree.
195  * I'm not sure if DWARF would have information of a single type in many
196  * different places (compilation units).  If not, it could compare the
197  * offset of the type entry in the .debug_info section.
198  */
199 static int data_type_cmp(const void *_key, const struct rb_node *node)
200 {
201 	const struct annotated_data_type *key = _key;
202 	struct annotated_data_type *type;
203 
204 	type = rb_entry(node, struct annotated_data_type, node);
205 
206 	if (key->self.size != type->self.size)
207 		return key->self.size - type->self.size;
208 	return strcmp(key->self.type_name, type->self.type_name);
209 }
210 
211 static bool data_type_less(struct rb_node *node_a, const struct rb_node *node_b)
212 {
213 	struct annotated_data_type *a, *b;
214 
215 	a = rb_entry(node_a, struct annotated_data_type, node);
216 	b = rb_entry(node_b, struct annotated_data_type, node);
217 
218 	if (a->self.size != b->self.size)
219 		return a->self.size < b->self.size;
220 	return strcmp(a->self.type_name, b->self.type_name) < 0;
221 }
222 
223 /* Recursively add new members for struct/union */
224 static int __add_member_cb(Dwarf_Die *die, void *arg)
225 {
226 	struct annotated_member *parent = arg;
227 	struct annotated_member *member;
228 	Dwarf_Die member_type, die_mem;
229 	Dwarf_Word size, loc, bit_size = 0;
230 	Dwarf_Attribute attr;
231 	struct strbuf sb;
232 	int tag;
233 
234 	if (dwarf_tag(die) != DW_TAG_member)
235 		return DIE_FIND_CB_SIBLING;
236 
237 	member = zalloc(sizeof(*member));
238 	if (member == NULL)
239 		return DIE_FIND_CB_END;
240 
241 	strbuf_init(&sb, 32);
242 	die_get_typename(die, &sb);
243 
244 	__die_get_real_type(die, &member_type);
245 	if (dwarf_tag(&member_type) == DW_TAG_typedef)
246 		die_get_real_type(&member_type, &die_mem);
247 	else
248 		die_mem = member_type;
249 
250 	if (dwarf_aggregate_size(&die_mem, &size) < 0)
251 		size = 0;
252 
253 	if (dwarf_attr_integrate(die, DW_AT_data_member_location, &attr))
254 		dwarf_formudata(&attr, &loc);
255 	else {
256 		/* bitfield member */
257 		if (dwarf_attr_integrate(die, DW_AT_data_bit_offset, &attr) &&
258 		    dwarf_formudata(&attr, &loc) == 0)
259 			loc /= 8;
260 		else
261 			loc = 0;
262 
263 		if (dwarf_attr_integrate(die, DW_AT_bit_size, &attr) &&
264 		    dwarf_formudata(&attr, &bit_size) == 0)
265 			size = (bit_size + 7) / 8;
266 	}
267 
268 	member->type_name = strbuf_detach(&sb, NULL);
269 	/* member->var_name can be NULL */
270 	if (dwarf_diename(die)) {
271 		if (bit_size) {
272 			if (asprintf(&member->var_name, "%s:%ld",
273 				     dwarf_diename(die), (long)bit_size) < 0)
274 				member->var_name = NULL;
275 		} else {
276 			member->var_name = strdup(dwarf_diename(die));
277 		}
278 
279 		if (member->var_name == NULL) {
280 			free(member);
281 			return DIE_FIND_CB_END;
282 		}
283 	}
284 	member->size = size;
285 	member->offset = loc + parent->offset;
286 	INIT_LIST_HEAD(&member->children);
287 	list_add_tail(&member->node, &parent->children);
288 
289 	tag = dwarf_tag(&die_mem);
290 	switch (tag) {
291 	case DW_TAG_structure_type:
292 	case DW_TAG_union_type:
293 		die_find_child(&die_mem, __add_member_cb, member, &die_mem);
294 		break;
295 	default:
296 		break;
297 	}
298 	return DIE_FIND_CB_SIBLING;
299 }
300 
301 static void add_member_types(struct annotated_data_type *parent, Dwarf_Die *type)
302 {
303 	Dwarf_Die die_mem;
304 
305 	die_find_child(type, __add_member_cb, &parent->self, &die_mem);
306 }
307 
308 static void delete_members(struct annotated_member *member)
309 {
310 	struct annotated_member *child, *tmp;
311 
312 	list_for_each_entry_safe(child, tmp, &member->children, node) {
313 		list_del(&child->node);
314 		delete_members(child);
315 		zfree(&child->type_name);
316 		zfree(&child->var_name);
317 		free(child);
318 	}
319 }
320 
321 static int fill_member_name(char *buf, size_t sz, struct annotated_member *m,
322 			    int offset, bool first)
323 {
324 	struct annotated_member *child;
325 
326 	if (list_empty(&m->children))
327 		return 0;
328 
329 	list_for_each_entry(child, &m->children, node) {
330 		int len;
331 
332 		if (offset < child->offset || offset >= child->offset + child->size)
333 			continue;
334 
335 		/* It can have anonymous struct/union members */
336 		if (child->var_name) {
337 			len = scnprintf(buf, sz, "%s%s",
338 					first ? "" : ".", child->var_name);
339 			first = false;
340 		} else {
341 			len = 0;
342 		}
343 
344 		return fill_member_name(buf + len, sz - len, child, offset, first) + len;
345 	}
346 	return 0;
347 }
348 
349 int annotated_data_type__get_member_name(struct annotated_data_type *adt,
350 					 char *buf, size_t sz, int member_offset)
351 {
352 	return fill_member_name(buf, sz, &adt->self, member_offset, /*first=*/true);
353 }
354 
355 static struct annotated_data_type *dso__findnew_data_type(struct dso *dso,
356 							  Dwarf_Die *type_die)
357 {
358 	struct annotated_data_type *result = NULL;
359 	struct annotated_data_type key;
360 	struct rb_node *node;
361 	struct strbuf sb;
362 	char *type_name;
363 	Dwarf_Word size;
364 
365 	strbuf_init(&sb, 32);
366 	if (die_get_typename_from_type(type_die, &sb) < 0)
367 		strbuf_add(&sb, "(unknown type)", 14);
368 	type_name = strbuf_detach(&sb, NULL);
369 
370 	if (dwarf_tag(type_die) == DW_TAG_typedef)
371 		die_get_real_type(type_die, type_die);
372 
373 	dwarf_aggregate_size(type_die, &size);
374 
375 	/* Check existing nodes in dso->data_types tree */
376 	key.self.type_name = type_name;
377 	key.self.size = size;
378 	node = rb_find(&key, dso__data_types(dso), data_type_cmp);
379 	if (node) {
380 		result = rb_entry(node, struct annotated_data_type, node);
381 		free(type_name);
382 		return result;
383 	}
384 
385 	/* If not, add a new one */
386 	result = zalloc(sizeof(*result));
387 	if (result == NULL) {
388 		free(type_name);
389 		return NULL;
390 	}
391 
392 	result->self.type_name = type_name;
393 	result->self.size = size;
394 	INIT_LIST_HEAD(&result->self.children);
395 
396 	if (symbol_conf.annotate_data_member)
397 		add_member_types(result, type_die);
398 
399 	rb_add(&result->node, dso__data_types(dso), data_type_less);
400 	return result;
401 }
402 
403 static bool find_cu_die(struct debuginfo *di, u64 pc, Dwarf_Die *cu_die)
404 {
405 	Dwarf_Off off, next_off;
406 	size_t header_size;
407 
408 	if (dwarf_addrdie(di->dbg, pc, cu_die) != NULL)
409 		return cu_die;
410 
411 	/*
412 	 * There are some kernels don't have full aranges and contain only a few
413 	 * aranges entries.  Fallback to iterate all CU entries in .debug_info
414 	 * in case it's missing.
415 	 */
416 	off = 0;
417 	while (dwarf_nextcu(di->dbg, off, &next_off, &header_size,
418 			    NULL, NULL, NULL) == 0) {
419 		if (dwarf_offdie(di->dbg, off + header_size, cu_die) &&
420 		    dwarf_haspc(cu_die, pc))
421 			return true;
422 
423 		off = next_off;
424 	}
425 	return false;
426 }
427 
428 enum type_match_result {
429 	PERF_TMR_UNKNOWN = 0,
430 	PERF_TMR_OK,
431 	PERF_TMR_NO_TYPE,
432 	PERF_TMR_NO_POINTER,
433 	PERF_TMR_NO_SIZE,
434 	PERF_TMR_BAD_OFFSET,
435 	PERF_TMR_BAIL_OUT,
436 };
437 
438 static const char *match_result_str(enum type_match_result tmr)
439 {
440 	switch (tmr) {
441 	case PERF_TMR_OK:
442 		return "Good!";
443 	case PERF_TMR_NO_TYPE:
444 		return "no type information";
445 	case PERF_TMR_NO_POINTER:
446 		return "no/void pointer";
447 	case PERF_TMR_NO_SIZE:
448 		return "type size is unknown";
449 	case PERF_TMR_BAD_OFFSET:
450 		return "offset bigger than size";
451 	case PERF_TMR_UNKNOWN:
452 	case PERF_TMR_BAIL_OUT:
453 	default:
454 		return "invalid state";
455 	}
456 }
457 
458 static bool is_compound_type(Dwarf_Die *type_die)
459 {
460 	int tag = dwarf_tag(type_die);
461 
462 	return tag == DW_TAG_structure_type || tag == DW_TAG_union_type;
463 }
464 
465 /* returns if Type B has better information than Type A */
466 static bool is_better_type(Dwarf_Die *type_a, Dwarf_Die *type_b)
467 {
468 	Dwarf_Word size_a, size_b;
469 	Dwarf_Die die_a, die_b;
470 	Dwarf_Die ptr_a, ptr_b;
471 	Dwarf_Die *ptr_type_a, *ptr_type_b;
472 
473 	ptr_type_a = die_get_pointer_type(type_a, &ptr_a);
474 	ptr_type_b = die_get_pointer_type(type_b, &ptr_b);
475 
476 	/* pointer type is preferred */
477 	if ((ptr_type_a != NULL) != (ptr_type_b != NULL))
478 		return ptr_type_b != NULL;
479 
480 	if (ptr_type_b) {
481 		/*
482 		 * We want to compare the target type, but 'void *' can fail to
483 		 * get the target type.
484 		 */
485 		if (die_get_real_type(ptr_type_a, &die_a) == NULL)
486 			return true;
487 		if (die_get_real_type(ptr_type_b, &die_b) == NULL)
488 			return false;
489 
490 		type_a = &die_a;
491 		type_b = &die_b;
492 	}
493 
494 	/* bigger type is preferred */
495 	if (dwarf_aggregate_size(type_a, &size_a) < 0 ||
496 	    dwarf_aggregate_size(type_b, &size_b) < 0)
497 		return false;
498 
499 	if (size_a != size_b)
500 		return size_a < size_b;
501 
502 	/* struct or union is preferred */
503 	if (is_compound_type(type_a) != is_compound_type(type_b))
504 		return is_compound_type(type_b);
505 
506 	/* typedef is preferred */
507 	if (dwarf_tag(type_b) == DW_TAG_typedef)
508 		return true;
509 
510 	return false;
511 }
512 
513 /* The type info will be saved in @type_die */
514 static enum type_match_result check_variable(struct data_loc_info *dloc,
515 					     Dwarf_Die *var_die,
516 					     Dwarf_Die *type_die, int reg,
517 					     int offset, bool is_fbreg)
518 {
519 	Dwarf_Word size;
520 	bool needs_pointer = true;
521 	Dwarf_Die sized_type;
522 
523 	if (reg == DWARF_REG_PC)
524 		needs_pointer = false;
525 	else if (reg == dloc->fbreg || is_fbreg)
526 		needs_pointer = false;
527 	else if (arch__is_x86(dloc->arch) && reg == X86_REG_SP)
528 		needs_pointer = false;
529 
530 	/* Get the type of the variable */
531 	if (__die_get_real_type(var_die, type_die) == NULL)
532 		return PERF_TMR_NO_TYPE;
533 
534 	/*
535 	 * Usually it expects a pointer type for a memory access.
536 	 * Convert to a real type it points to.  But global variables
537 	 * and local variables are accessed directly without a pointer.
538 	 */
539 	if (needs_pointer) {
540 		if (die_get_pointer_type(type_die, type_die) == NULL ||
541 		    __die_get_real_type(type_die, type_die) == NULL)
542 			return PERF_TMR_NO_POINTER;
543 	}
544 
545 	if (dwarf_tag(type_die) == DW_TAG_typedef)
546 		die_get_real_type(type_die, &sized_type);
547 	else
548 		sized_type = *type_die;
549 
550 	/* Get the size of the actual type */
551 	if (dwarf_aggregate_size(&sized_type, &size) < 0)
552 		return PERF_TMR_NO_SIZE;
553 
554 	/* Minimal sanity check */
555 	if ((unsigned)offset >= size)
556 		return PERF_TMR_BAD_OFFSET;
557 
558 	return PERF_TMR_OK;
559 }
560 
561 struct type_state_stack *find_stack_state(struct type_state *state,
562 						 int offset)
563 {
564 	struct type_state_stack *stack;
565 
566 	list_for_each_entry(stack, &state->stack_vars, list) {
567 		if (offset == stack->offset)
568 			return stack;
569 
570 		if (stack->compound && stack->offset < offset &&
571 		    offset < stack->offset + stack->size)
572 			return stack;
573 	}
574 	return NULL;
575 }
576 
577 void set_stack_state(struct type_state_stack *stack, int offset, u8 kind,
578 			    Dwarf_Die *type_die, int ptr_offset)
579 {
580 	int tag;
581 	Dwarf_Word size;
582 
583 	if (kind == TSR_KIND_POINTER) {
584 		/* TODO: arch-dependent pointer size */
585 		size = sizeof(void *);
586 	}
587 	else if (dwarf_aggregate_size(type_die, &size) < 0)
588 		size = 0;
589 
590 	stack->type = *type_die;
591 	stack->size = size;
592 	stack->offset = offset;
593 	stack->ptr_offset = ptr_offset;
594 	stack->kind = kind;
595 
596 	if (kind == TSR_KIND_POINTER) {
597 		stack->compound = false;
598 		return;
599 	}
600 
601 	tag = dwarf_tag(type_die);
602 
603 	switch (tag) {
604 	case DW_TAG_structure_type:
605 	case DW_TAG_union_type:
606 		stack->compound = (kind != TSR_KIND_PERCPU_POINTER);
607 		break;
608 	default:
609 		stack->compound = false;
610 		break;
611 	}
612 }
613 
614 struct type_state_stack *findnew_stack_state(struct type_state *state,
615 						    int offset, u8 kind,
616 						    Dwarf_Die *type_die,
617 						    int ptr_offset)
618 {
619 	struct type_state_stack *stack = find_stack_state(state, offset);
620 
621 	if (stack) {
622 		set_stack_state(stack, offset, kind, type_die, ptr_offset);
623 		return stack;
624 	}
625 
626 	stack = malloc(sizeof(*stack));
627 	if (stack) {
628 		set_stack_state(stack, offset, kind, type_die, ptr_offset);
629 		list_add(&stack->list, &state->stack_vars);
630 	}
631 	return stack;
632 }
633 
634 /* Maintain a cache for quick global variable lookup */
635 struct global_var_entry {
636 	struct rb_node node;
637 	char *name;
638 	u64 start;
639 	u64 end;
640 	u64 die_offset;
641 };
642 
643 static int global_var_cmp(const void *_key, const struct rb_node *node)
644 {
645 	const u64 addr = (uintptr_t)_key;
646 	struct global_var_entry *gvar;
647 
648 	gvar = rb_entry(node, struct global_var_entry, node);
649 
650 	if (gvar->start <= addr && addr < gvar->end)
651 		return 0;
652 	return gvar->start > addr ? -1 : 1;
653 }
654 
655 static bool global_var_less(struct rb_node *node_a, const struct rb_node *node_b)
656 {
657 	struct global_var_entry *gvar_a, *gvar_b;
658 
659 	gvar_a = rb_entry(node_a, struct global_var_entry, node);
660 	gvar_b = rb_entry(node_b, struct global_var_entry, node);
661 
662 	return gvar_a->start < gvar_b->start;
663 }
664 
665 static struct global_var_entry *global_var__find(struct data_loc_info *dloc, u64 addr)
666 {
667 	struct dso *dso = map__dso(dloc->ms->map);
668 	struct rb_node *node;
669 
670 	node = rb_find((void *)(uintptr_t)addr, dso__global_vars(dso), global_var_cmp);
671 	if (node == NULL)
672 		return NULL;
673 
674 	return rb_entry(node, struct global_var_entry, node);
675 }
676 
677 static bool global_var__add(struct data_loc_info *dloc, u64 addr,
678 			    const char *name, Dwarf_Die *type_die)
679 {
680 	struct dso *dso = map__dso(dloc->ms->map);
681 	struct global_var_entry *gvar;
682 	Dwarf_Word size;
683 
684 	if (dwarf_aggregate_size(type_die, &size) < 0)
685 		return false;
686 
687 	gvar = malloc(sizeof(*gvar));
688 	if (gvar == NULL)
689 		return false;
690 
691 	gvar->name = name ? strdup(name) : NULL;
692 	if (name && gvar->name == NULL) {
693 		free(gvar);
694 		return false;
695 	}
696 
697 	gvar->start = addr;
698 	gvar->end = addr + size;
699 	gvar->die_offset = dwarf_dieoffset(type_die);
700 
701 	rb_add(&gvar->node, dso__global_vars(dso), global_var_less);
702 	return true;
703 }
704 
705 void global_var_type__tree_delete(struct rb_root *root)
706 {
707 	struct global_var_entry *gvar;
708 
709 	while (!RB_EMPTY_ROOT(root)) {
710 		struct rb_node *node = rb_first(root);
711 
712 		rb_erase(node, root);
713 		gvar = rb_entry(node, struct global_var_entry, node);
714 		zfree(&gvar->name);
715 		free(gvar);
716 	}
717 }
718 
719 bool get_global_var_info(struct data_loc_info *dloc, u64 addr,
720 				const char **var_name, int *var_offset)
721 {
722 	struct addr_location al;
723 	struct symbol *sym;
724 	u64 mem_addr;
725 
726 	/* Kernel symbols might be relocated */
727 	mem_addr = addr + map__reloc(dloc->ms->map);
728 
729 	addr_location__init(&al);
730 	sym = thread__find_symbol_fb(dloc->thread, dloc->cpumode,
731 				     mem_addr, &al);
732 	if (sym) {
733 		*var_name = sym->name;
734 		/* Calculate type offset from the start of variable */
735 		*var_offset = mem_addr - map__unmap_ip(al.map, sym->start);
736 	} else {
737 		*var_name = NULL;
738 	}
739 	addr_location__exit(&al);
740 	if (*var_name == NULL)
741 		return false;
742 
743 	return true;
744 }
745 
746 static void global_var__collect(struct data_loc_info *dloc)
747 {
748 	Dwarf *dwarf = dloc->di->dbg;
749 	Dwarf_Off off, next_off;
750 	Dwarf_Die cu_die, type_die;
751 	size_t header_size;
752 
753 	/* Iterate all CU and collect global variables that have no location in a register. */
754 	off = 0;
755 	while (dwarf_nextcu(dwarf, off, &next_off, &header_size,
756 			    NULL, NULL, NULL) == 0) {
757 		struct die_var_type *var_types = NULL;
758 		struct die_var_type *pos;
759 
760 		if (dwarf_offdie(dwarf, off + header_size, &cu_die) == NULL) {
761 			off = next_off;
762 			continue;
763 		}
764 
765 		die_collect_global_vars(&cu_die, &var_types);
766 
767 		for (pos = var_types; pos; pos = pos->next) {
768 			const char *var_name = NULL;
769 			int var_offset = 0;
770 
771 			if (pos->reg != -1)
772 				continue;
773 
774 			if (!dwarf_offdie(dwarf, pos->die_off, &type_die))
775 				continue;
776 
777 			get_global_var_info(dloc, pos->addr, &var_name, &var_offset);
778 
779 			global_var__add(dloc, pos->addr, var_name, &type_die);
780 		}
781 
782 		delete_var_types(var_types);
783 
784 		off = next_off;
785 	}
786 }
787 
788 bool get_global_var_type(Dwarf_Die *cu_die, struct data_loc_info *dloc,
789 				u64 ip, u64 var_addr, int *var_offset,
790 				Dwarf_Die *type_die)
791 {
792 	u64 pc;
793 	int offset;
794 	const char *var_name = NULL;
795 	struct global_var_entry *gvar;
796 	struct dso *dso = map__dso(dloc->ms->map);
797 	Dwarf_Die var_die;
798 
799 	if (RB_EMPTY_ROOT(dso__global_vars(dso)))
800 		global_var__collect(dloc);
801 
802 	gvar = global_var__find(dloc, var_addr);
803 	if (gvar) {
804 		if (!dwarf_offdie(dloc->di->dbg, gvar->die_offset, type_die))
805 			return false;
806 
807 		*var_offset = var_addr - gvar->start;
808 		return true;
809 	}
810 
811 	/* Try to get the variable by address first */
812 	if (die_find_variable_by_addr(cu_die, var_addr, &var_die, type_die,
813 				      &offset)) {
814 		var_name = dwarf_diename(&var_die);
815 		*var_offset = offset;
816 		goto ok;
817 	}
818 
819 	if (!get_global_var_info(dloc, var_addr, &var_name, var_offset))
820 		return false;
821 
822 	pc = map__rip_2objdump(dloc->ms->map, ip);
823 
824 	/* Try to get the name of global variable */
825 	if (die_find_variable_at(cu_die, var_name, pc, &var_die) &&
826 	    check_variable(dloc, &var_die, type_die, DWARF_REG_PC, *var_offset,
827 			   /*is_fbreg=*/false) == PERF_TMR_OK)
828 		goto ok;
829 
830 	return false;
831 
832 ok:
833 	/* The address should point to the start of the variable */
834 	global_var__add(dloc, var_addr - *var_offset, var_name, type_die);
835 	return true;
836 }
837 
838 static bool die_is_same(Dwarf_Die *die_a, Dwarf_Die *die_b)
839 {
840 	return (die_a->cu == die_b->cu) && (die_a->addr == die_b->addr);
841 }
842 
843 static void tsr_set_lifetime(struct type_state_reg *tsr,
844 			     const struct die_var_type *var)
845 {
846 	if (var && var->has_range && var->end > var->addr) {
847 		tsr->lifetime_active = true;
848 		tsr->lifetime_end = var->end;
849 	} else {
850 		tsr->lifetime_active = false;
851 		tsr->lifetime_end = 0;
852 	}
853 }
854 
855 /**
856  * update_var_state - Update type state using given variables
857  * @state: type state table
858  * @dloc: data location info
859  * @addr: instruction address to match with variable
860  * @insn_offset: instruction offset (for debug)
861  * @var_types: list of variables with type info
862  *
863  * This function fills the @state table using @var_types info.  Each variable
864  * is used only at the given location and updates an entry in the table.
865  */
866 static void update_var_state(struct type_state *state, struct data_loc_info *dloc,
867 			     u64 addr, u64 insn_offset, struct die_var_type *var_types)
868 {
869 	Dwarf_Die mem_die;
870 	struct die_var_type *var;
871 	int fbreg = dloc->fbreg;
872 	int fb_offset = 0;
873 
874 	if (dloc->fb_cfa) {
875 		if (die_get_cfa(dloc->di->dbg, addr, &fbreg, &fb_offset) < 0)
876 			fbreg = -1;
877 	}
878 
879 	for (var = var_types; var != NULL; var = var->next) {
880 		/* Check if addr falls within the variable's valid range */
881 		if (var->has_range) {
882 			if (addr < var->addr || (var->end && addr >= var->end))
883 				continue;
884 		} else {
885 			if (addr != var->addr)
886 				continue;
887 		}
888 		/* Get the type DIE using the offset */
889 		if (!dwarf_offdie(dloc->di->dbg, var->die_off, &mem_die))
890 			continue;
891 
892 		if (var->reg == DWARF_REG_FB || var->reg == fbreg || var->reg == state->stack_reg) {
893 			Dwarf_Die ptr_die;
894 			Dwarf_Die *ptr_type;
895 			int offset = var->offset;
896 			struct type_state_stack *stack;
897 
898 			ptr_type = die_get_pointer_type(&mem_die, &ptr_die);
899 
900 			/* If the reg location holds the pointer value, dereference the type */
901 			if (!var->is_reg_var_addr && ptr_type &&
902 			    __die_get_real_type(ptr_type, &mem_die) == NULL)
903 				continue;
904 
905 			if (var->reg != DWARF_REG_FB)
906 				offset -= fb_offset;
907 
908 			stack = find_stack_state(state, offset);
909 			if (stack && stack->kind == TSR_KIND_TYPE &&
910 			    !is_better_type(&stack->type, &mem_die))
911 				continue;
912 
913 			findnew_stack_state(state, offset, TSR_KIND_TYPE,
914 					    &mem_die, /*ptr_offset=*/0);
915 
916 			if (var->reg == state->stack_reg) {
917 				pr_debug_dtp("var [%"PRIx64"] %#x(reg%d)",
918 					     insn_offset, offset, state->stack_reg);
919 			} else {
920 				pr_debug_dtp("var [%"PRIx64"] -%#x(stack)",
921 					     insn_offset, -offset);
922 			}
923 			pr_debug_type_name(&mem_die, TSR_KIND_TYPE);
924 		} else if (has_reg_type(state, var->reg)) {
925 			struct type_state_reg *reg;
926 			Dwarf_Die orig_type;
927 
928 			reg = &state->regs[var->reg];
929 
930 			if (reg->ok && reg->kind == TSR_KIND_TYPE &&
931 			   (!is_better_type(&reg->type, &mem_die) || var->is_reg_var_addr))
932 				continue;
933 
934 			/* Handle address registers with TSR_KIND_POINTER */
935 			if (var->is_reg_var_addr) {
936 				if (reg->ok && reg->kind == TSR_KIND_POINTER &&
937 				    !is_better_type(&reg->type, &mem_die))
938 					continue;
939 
940 				reg->offset = -var->offset;
941 				reg->type = mem_die;
942 				reg->kind = TSR_KIND_POINTER;
943 				reg->ok = true;
944 				tsr_set_lifetime(reg, var);
945 
946 				pr_debug_dtp("var [%"PRIx64"] reg%d addr offset %x",
947 					     insn_offset, var->reg, var->offset);
948 				pr_debug_type_name(&mem_die, TSR_KIND_POINTER);
949 				continue;
950 			}
951 
952 			orig_type = reg->type;
953 			/*
954 			 * var->offset + reg value is the beginning of the struct
955 			 * reg->offset is the offset the reg points
956 			 */
957 			reg->offset = -var->offset;
958 			reg->type = mem_die;
959 			reg->kind = TSR_KIND_TYPE;
960 			reg->ok = true;
961 			tsr_set_lifetime(reg, var);
962 
963 			pr_debug_dtp("var [%"PRIx64"] reg%d offset %x",
964 				     insn_offset, var->reg, var->offset);
965 			pr_debug_type_name(&mem_die, TSR_KIND_TYPE);
966 
967 			/*
968 			 * If this register is directly copied from another and it gets a
969 			 * better type, also update the type of the source register.  This
970 			 * is usually the case of container_of() macro with offset of 0.
971 			 */
972 			if (has_reg_type(state, reg->copied_from)) {
973 				struct type_state_reg *copy_reg;
974 
975 				copy_reg = &state->regs[reg->copied_from];
976 
977 				/* TODO: check if type is compatible or embedded */
978 				if (!copy_reg->ok || (copy_reg->kind != TSR_KIND_TYPE) ||
979 				    !die_is_same(&copy_reg->type, &orig_type) ||
980 				    !is_better_type(&copy_reg->type, &mem_die))
981 					continue;
982 
983 				copy_reg->type = mem_die;
984 
985 				pr_debug_dtp("var [%"PRIx64"] copyback reg%d",
986 					     insn_offset, reg->copied_from);
987 				pr_debug_type_name(&mem_die, TSR_KIND_TYPE);
988 			}
989 		}
990 	}
991 }
992 
993 /**
994  * update_insn_state - Update type state for an instruction
995  * @state: type state table
996  * @dloc: data location info
997  * @cu_die: compile unit debug entry
998  * @dl: disasm line for the instruction
999  *
1000  * This function updates the @state table for the target operand of the
1001  * instruction at @dl if it transfers the type like MOV on x86.  Since it
1002  * tracks the type, it won't care about the values like in arithmetic
1003  * instructions like ADD/SUB/MUL/DIV and INC/DEC.
1004  *
1005  * Note that ops->reg2 is only available when both mem_ref and multi_regs
1006  * are true.
1007  */
1008 static void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
1009 			      Dwarf_Die *cu_die, struct disasm_line *dl)
1010 {
1011 	if (dloc->arch->update_insn_state)
1012 		dloc->arch->update_insn_state(state, dloc, cu_die, dl);
1013 }
1014 
1015 /*
1016  * Prepend this_blocks (from the outer scope) to full_blocks, removing
1017  * duplicate disasm line.
1018  */
1019 static void prepend_basic_blocks(struct list_head *this_blocks,
1020 				 struct list_head *full_blocks)
1021 {
1022 	struct annotated_basic_block *first_bb, *last_bb;
1023 
1024 	last_bb = list_last_entry(this_blocks, typeof(*last_bb), list);
1025 	first_bb = list_first_entry(full_blocks, typeof(*first_bb), list);
1026 
1027 	if (list_empty(full_blocks))
1028 		goto out;
1029 
1030 	/* Last insn in this_blocks should be same as first insn in full_blocks */
1031 	if (last_bb->end != first_bb->begin) {
1032 		pr_debug("prepend basic blocks: mismatched disasm line %"PRIx64" -> %"PRIx64"\n",
1033 			 last_bb->end->al.offset, first_bb->begin->al.offset);
1034 		goto out;
1035 	}
1036 
1037 	/* Is the basic block have only one disasm_line? */
1038 	if (last_bb->begin == last_bb->end) {
1039 		list_del(&last_bb->list);
1040 		free(last_bb);
1041 		goto out;
1042 	}
1043 
1044 	/* Point to the insn before the last when adding this block to full_blocks */
1045 	last_bb->end = list_prev_entry(last_bb->end, al.node);
1046 
1047 out:
1048 	list_splice(this_blocks, full_blocks);
1049 }
1050 
1051 static void delete_basic_blocks(struct list_head *basic_blocks)
1052 {
1053 	struct annotated_basic_block *bb, *tmp;
1054 
1055 	list_for_each_entry_safe(bb, tmp, basic_blocks, list) {
1056 		list_del(&bb->list);
1057 		free(bb);
1058 	}
1059 }
1060 
1061 /* Make sure all variables have a valid start address */
1062 static void fixup_var_address(struct die_var_type *var_types, u64 addr)
1063 {
1064 	while (var_types) {
1065 		/*
1066 		 * Some variables have no address range meaning it's always
1067 		 * available in the whole scope.  Let's adjust the start
1068 		 * address to the start of the scope.
1069 		 */
1070 		if (var_types->addr == 0)
1071 			var_types->addr = addr;
1072 
1073 		var_types = var_types->next;
1074 	}
1075 }
1076 
1077 static void delete_var_types(struct die_var_type *var_types)
1078 {
1079 	while (var_types) {
1080 		struct die_var_type *next = var_types->next;
1081 
1082 		free(var_types);
1083 		var_types = next;
1084 	}
1085 }
1086 
1087 /* should match to is_stack_canary() in util/annotate.c */
1088 static void setup_stack_canary(struct data_loc_info *dloc)
1089 {
1090 	if (arch__is_x86(dloc->arch)) {
1091 		dloc->op->segment = INSN_SEG_X86_GS;
1092 		dloc->op->imm = true;
1093 		dloc->op->offset = 40;
1094 	}
1095 }
1096 
1097 /*
1098  * It's at the target address, check if it has a matching type.
1099  * It returns PERF_TMR_BAIL_OUT when it looks up per-cpu variables which
1100  * are similar to global variables and no additional info is needed.
1101  */
1102 static enum type_match_result check_matching_type(struct type_state *state,
1103 						  struct data_loc_info *dloc,
1104 						  Dwarf_Die *cu_die,
1105 						  struct disasm_line *dl,
1106 						  Dwarf_Die *type_die)
1107 {
1108 	Dwarf_Word size;
1109 	u32 insn_offset = dl->al.offset;
1110 	int reg = dloc->op->reg1;
1111 	int offset = dloc->op->offset;
1112 	const char *offset_sign = "";
1113 	bool retry = true;
1114 
1115 	if (offset < 0) {
1116 		offset = -offset;
1117 		offset_sign = "-";
1118 	}
1119 
1120 again:
1121 	pr_debug_dtp("chk [%x] reg%d offset=%s%#x ok=%d kind=%d ",
1122 		     insn_offset, reg, offset_sign, offset,
1123 		     state->regs[reg].ok, state->regs[reg].kind);
1124 
1125 	if (!state->regs[reg].ok)
1126 		goto check_non_register;
1127 
1128 	if (state->regs[reg].kind == TSR_KIND_TYPE) {
1129 		Dwarf_Die ptr_die;
1130 		Dwarf_Die sized_type;
1131 		Dwarf_Die *ptr_type;
1132 		struct strbuf sb;
1133 
1134 		strbuf_init(&sb, 32);
1135 		die_get_typename_from_type(&state->regs[reg].type, &sb);
1136 		pr_debug_dtp("(%s)", sb.buf);
1137 		strbuf_release(&sb);
1138 
1139 		/*
1140 		 * Normal registers should hold a pointer (or array) to
1141 		 * dereference a memory location.
1142 		 */
1143 		ptr_type = die_get_pointer_type(&state->regs[reg].type, &ptr_die);
1144 		if (!ptr_type) {
1145 			if (dloc->op->offset < 0 && reg != state->stack_reg)
1146 				goto check_kernel;
1147 
1148 			return PERF_TMR_NO_POINTER;
1149 		}
1150 
1151 		/* Remove the pointer and get the target type */
1152 		if (__die_get_real_type(ptr_type, type_die) == NULL)
1153 			return PERF_TMR_NO_POINTER;
1154 
1155 		dloc->type_offset = dloc->op->offset + state->regs[reg].offset;
1156 
1157 		if (dwarf_tag(type_die) == DW_TAG_typedef)
1158 			die_get_real_type(type_die, &sized_type);
1159 		else
1160 			sized_type = *type_die;
1161 
1162 		/* Get the size of the actual type */
1163 		if (dwarf_aggregate_size(&sized_type, &size) < 0 ||
1164 		    (unsigned)dloc->type_offset >= size)
1165 			return PERF_TMR_BAD_OFFSET;
1166 
1167 		return PERF_TMR_OK;
1168 	}
1169 
1170 	if (state->regs[reg].kind == TSR_KIND_POINTER) {
1171 		struct strbuf sb;
1172 
1173 		strbuf_init(&sb, 32);
1174 		die_get_typename_from_type(&state->regs[reg].type, &sb);
1175 		pr_debug_dtp("(ptr->%s)", sb.buf);
1176 		strbuf_release(&sb);
1177 
1178 		/*
1179 		 * Register holds a pointer (address) to the target variable.
1180 		 * The type is the type of the variable it points to.
1181 		 */
1182 		*type_die = state->regs[reg].type;
1183 
1184 		dloc->type_offset = dloc->op->offset + state->regs[reg].offset;
1185 
1186 		/* Get the size of the actual type */
1187 		if (dwarf_aggregate_size(type_die, &size) < 0 ||
1188 		    (unsigned)dloc->type_offset >= size)
1189 			return PERF_TMR_BAD_OFFSET;
1190 
1191 		return PERF_TMR_OK;
1192 	}
1193 
1194 	if (state->regs[reg].kind == TSR_KIND_PERCPU_POINTER) {
1195 		pr_debug_dtp("percpu ptr");
1196 
1197 		/*
1198 		 * It's actaully pointer but the address was calculated using
1199 		 * some arithmetic.  So it points to the actual type already.
1200 		 */
1201 		*type_die = state->regs[reg].type;
1202 
1203 		dloc->type_offset = dloc->op->offset;
1204 
1205 		/* Get the size of the actual type */
1206 		if (dwarf_aggregate_size(type_die, &size) < 0 ||
1207 		    (unsigned)dloc->type_offset >= size)
1208 			return PERF_TMR_BAIL_OUT;
1209 
1210 		return PERF_TMR_OK;
1211 	}
1212 
1213 	if (state->regs[reg].kind == TSR_KIND_CANARY) {
1214 		pr_debug_dtp("stack canary");
1215 
1216 		/*
1217 		 * This is a saved value of the stack canary which will be handled
1218 		 * in the outer logic when it returns failure here.  Pretend it's
1219 		 * from the stack canary directly.
1220 		 */
1221 		setup_stack_canary(dloc);
1222 
1223 		return PERF_TMR_BAIL_OUT;
1224 	}
1225 
1226 	if (state->regs[reg].kind == TSR_KIND_PERCPU_BASE) {
1227 		u64 var_addr = dloc->op->offset;
1228 		int var_offset;
1229 
1230 		pr_debug_dtp("percpu var");
1231 
1232 		if (dloc->op->multi_regs) {
1233 			int reg2 = dloc->op->reg2;
1234 
1235 			if (dloc->op->reg2 == reg)
1236 				reg2 = dloc->op->reg1;
1237 
1238 			if (has_reg_type(state, reg2) && state->regs[reg2].ok &&
1239 			    state->regs[reg2].kind == TSR_KIND_CONST)
1240 				var_addr += state->regs[reg2].imm_value;
1241 		}
1242 
1243 		if (get_global_var_type(cu_die, dloc, dloc->ip, var_addr,
1244 					&var_offset, type_die)) {
1245 			dloc->type_offset = var_offset;
1246 			return PERF_TMR_OK;
1247 		}
1248 		/* No need to retry per-cpu (global) variables */
1249 		return PERF_TMR_BAIL_OUT;
1250 	}
1251 
1252 	if (state->regs[reg].kind == TSR_KIND_CONST &&
1253 	    dso__kernel(map__dso(dloc->ms->map))) {
1254 		if (dloc->op->offset < 0 && reg != state->stack_reg && reg != dloc->fbreg)
1255 			goto check_kernel;
1256 	}
1257 check_non_register:
1258 	if (reg == dloc->fbreg || reg == state->stack_reg) {
1259 		struct type_state_stack *stack;
1260 
1261 		pr_debug_dtp("%s", reg == dloc->fbreg ? "fbreg" : "stack");
1262 
1263 		stack = find_stack_state(state, dloc->type_offset);
1264 		if (stack == NULL) {
1265 			if (retry) {
1266 				pr_debug_dtp(" : retry\n");
1267 				retry = false;
1268 
1269 				/* update type info it's the first store to the stack */
1270 				update_insn_state(state, dloc, cu_die, dl);
1271 				goto again;
1272 			}
1273 			return PERF_TMR_NO_TYPE;
1274 		}
1275 
1276 		if (stack->kind == TSR_KIND_CANARY) {
1277 			setup_stack_canary(dloc);
1278 			return PERF_TMR_BAIL_OUT;
1279 		}
1280 
1281 		if (stack->kind != TSR_KIND_TYPE)
1282 			return PERF_TMR_NO_TYPE;
1283 
1284 		*type_die = stack->type;
1285 		/* Update the type offset from the start of slot */
1286 		dloc->type_offset -= stack->offset;
1287 
1288 		return PERF_TMR_OK;
1289 	}
1290 
1291 	if (dloc->fb_cfa) {
1292 		struct type_state_stack *stack;
1293 		u64 pc = map__rip_2objdump(dloc->ms->map, dloc->ip);
1294 		int fbreg, fboff;
1295 
1296 		pr_debug_dtp("cfa");
1297 
1298 		if (die_get_cfa(dloc->di->dbg, pc, &fbreg, &fboff) < 0)
1299 			fbreg = -1;
1300 
1301 		if (reg != fbreg)
1302 			return PERF_TMR_NO_TYPE;
1303 
1304 		stack = find_stack_state(state, dloc->type_offset - fboff);
1305 		if (stack == NULL) {
1306 			if (retry) {
1307 				pr_debug_dtp(" : retry\n");
1308 				retry = false;
1309 
1310 				/* update type info it's the first store to the stack */
1311 				update_insn_state(state, dloc, cu_die, dl);
1312 				goto again;
1313 			}
1314 			return PERF_TMR_NO_TYPE;
1315 		}
1316 
1317 		if (stack->kind == TSR_KIND_CANARY) {
1318 			setup_stack_canary(dloc);
1319 			return PERF_TMR_BAIL_OUT;
1320 		}
1321 
1322 		if (stack->kind != TSR_KIND_TYPE)
1323 			return PERF_TMR_NO_TYPE;
1324 
1325 		*type_die = stack->type;
1326 		/* Update the type offset from the start of slot */
1327 		dloc->type_offset -= fboff + stack->offset;
1328 
1329 		return PERF_TMR_OK;
1330 	}
1331 
1332 check_kernel:
1333 	if (dso__kernel(map__dso(dloc->ms->map))) {
1334 		u64 addr;
1335 
1336 		/* Direct this-cpu access like "%gs:0x34740" */
1337 		if (dloc->op->segment == INSN_SEG_X86_GS && dloc->op->imm &&
1338 		    arch__is_x86(dloc->arch)) {
1339 			pr_debug_dtp("this-cpu var");
1340 
1341 			addr = dloc->op->offset;
1342 
1343 			if (get_global_var_type(cu_die, dloc, dloc->ip, addr,
1344 						&offset, type_die)) {
1345 				dloc->type_offset = offset;
1346 				return PERF_TMR_OK;
1347 			}
1348 			return PERF_TMR_BAIL_OUT;
1349 		}
1350 
1351 		/* Access to global variable like "-0x7dcf0500(,%rdx,8)" */
1352 		if (dloc->op->offset < 0 && reg != state->stack_reg) {
1353 			addr = (s64) dloc->op->offset;
1354 
1355 			if (get_global_var_type(cu_die, dloc, dloc->ip, addr,
1356 						&offset, type_die)) {
1357 				pr_debug_dtp("global var");
1358 
1359 				dloc->type_offset = offset;
1360 				return PERF_TMR_OK;
1361 			}
1362 			return PERF_TMR_BAIL_OUT;
1363 		}
1364 	}
1365 
1366 	return PERF_TMR_UNKNOWN;
1367 }
1368 
1369 /* Iterate instructions in basic blocks and update type table */
1370 static enum type_match_result find_data_type_insn(struct data_loc_info *dloc,
1371 						  struct list_head *basic_blocks,
1372 						  struct die_var_type *var_types,
1373 						  Dwarf_Die *cu_die,
1374 						  Dwarf_Die *type_die)
1375 {
1376 	struct type_state state;
1377 	struct symbol *sym = dloc->ms->sym;
1378 	struct annotation *notes = symbol__annotation(sym);
1379 	struct annotated_basic_block *bb;
1380 	enum type_match_result ret = PERF_TMR_UNKNOWN;
1381 
1382 	init_type_state(&state, dloc->arch);
1383 
1384 	list_for_each_entry(bb, basic_blocks, list) {
1385 		struct disasm_line *dl = bb->begin;
1386 
1387 		BUG_ON(bb->begin->al.offset == -1 || bb->end->al.offset == -1);
1388 
1389 		pr_debug_dtp("bb: [%"PRIx64" - %"PRIx64"]\n",
1390 			     bb->begin->al.offset, bb->end->al.offset);
1391 
1392 		list_for_each_entry_from(dl, &notes->src->source, al.node) {
1393 			u64 this_ip = sym->start + dl->al.offset;
1394 			u64 addr = map__rip_2objdump(dloc->ms->map, this_ip);
1395 
1396 			/* Skip comment or debug info lines */
1397 			if (dl->al.offset == -1)
1398 				continue;
1399 
1400 			/* Update variable type at this address */
1401 			update_var_state(&state, dloc, addr, dl->al.offset, var_types);
1402 
1403 			if (this_ip == dloc->ip) {
1404 				ret = check_matching_type(&state, dloc,
1405 							  cu_die, dl, type_die);
1406 				pr_debug_dtp(" : %s\n", match_result_str(ret));
1407 				goto out;
1408 			}
1409 
1410 			/* Update type table after processing the instruction */
1411 			update_insn_state(&state, dloc, cu_die, dl);
1412 			if (dl == bb->end)
1413 				break;
1414 		}
1415 	}
1416 
1417 out:
1418 	exit_type_state(&state);
1419 	return ret;
1420 }
1421 
1422 static int arch_supports_insn_tracking(struct data_loc_info *dloc)
1423 {
1424 	if ((arch__is_x86(dloc->arch)) || (arch__is_powerpc(dloc->arch)))
1425 		return 1;
1426 	return 0;
1427 }
1428 
1429 /*
1430  * Construct a list of basic blocks for each scope with variables and try to find
1431  * the data type by updating a type state table through instructions.
1432  */
1433 static enum type_match_result find_data_type_block(struct data_loc_info *dloc,
1434 						   Dwarf_Die *cu_die,
1435 						   Dwarf_Die *scopes,
1436 						   int nr_scopes,
1437 						   Dwarf_Die *type_die)
1438 {
1439 	LIST_HEAD(basic_blocks);
1440 	struct die_var_type *var_types = NULL;
1441 	u64 src_ip, dst_ip, prev_dst_ip;
1442 	enum type_match_result ret = PERF_TMR_UNKNOWN;
1443 
1444 	/* TODO: other architecture support */
1445 	if (!arch_supports_insn_tracking(dloc))
1446 		return PERF_TMR_BAIL_OUT;
1447 
1448 	prev_dst_ip = dst_ip = dloc->ip;
1449 	for (int i = nr_scopes - 1; i >= 0; i--) {
1450 		Dwarf_Addr base, start, end;
1451 		LIST_HEAD(this_blocks);
1452 
1453 		if (dwarf_ranges(&scopes[i], 0, &base, &start, &end) < 0)
1454 			break;
1455 
1456 		pr_debug_dtp("scope: [%d/%d] ", i + 1, nr_scopes);
1457 		pr_debug_scope(&scopes[i]);
1458 
1459 		src_ip = map__objdump_2rip(dloc->ms->map, start);
1460 
1461 again:
1462 		/* Get basic blocks for this scope */
1463 		if (annotate_get_basic_blocks(dloc->ms->sym, src_ip, dst_ip,
1464 					      &this_blocks) < 0) {
1465 			/* Try previous block if they are not connected */
1466 			if (prev_dst_ip != dst_ip) {
1467 				dst_ip = prev_dst_ip;
1468 				goto again;
1469 			}
1470 
1471 			pr_debug_dtp("cannot find a basic block from %"PRIx64" to %"PRIx64"\n",
1472 				     src_ip - dloc->ms->sym->start,
1473 				     dst_ip - dloc->ms->sym->start);
1474 			continue;
1475 		}
1476 		prepend_basic_blocks(&this_blocks, &basic_blocks);
1477 
1478 		/* Get variable info for this scope and add to var_types list */
1479 		die_collect_vars(&scopes[i], &var_types);
1480 		fixup_var_address(var_types, start);
1481 
1482 		/* Find from start of this scope to the target instruction */
1483 		ret = find_data_type_insn(dloc, &basic_blocks, var_types,
1484 					    cu_die, type_die);
1485 		if (ret == PERF_TMR_OK) {
1486 			char buf[64];
1487 			int offset = dloc->op->offset;
1488 			const char *offset_sign = "";
1489 
1490 			if (offset < 0) {
1491 				offset = -offset;
1492 				offset_sign = "-";
1493 			}
1494 
1495 			if (dloc->op->multi_regs)
1496 				snprintf(buf, sizeof(buf), "reg%d, reg%d",
1497 					 dloc->op->reg1, dloc->op->reg2);
1498 			else
1499 				snprintf(buf, sizeof(buf), "reg%d", dloc->op->reg1);
1500 
1501 			pr_debug_dtp("found by insn track: %s%#x(%s) type-offset=%#x\n",
1502 				     offset_sign, offset, buf, dloc->type_offset);
1503 			break;
1504 		}
1505 
1506 		if (ret == PERF_TMR_BAIL_OUT)
1507 			break;
1508 
1509 		/* Go up to the next scope and find blocks to the start */
1510 		prev_dst_ip = dst_ip;
1511 		dst_ip = src_ip;
1512 	}
1513 
1514 	delete_basic_blocks(&basic_blocks);
1515 	delete_var_types(var_types);
1516 	return ret;
1517 }
1518 
1519 /* The result will be saved in @type_die */
1520 static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
1521 {
1522 	struct annotated_op_loc *loc = dloc->op;
1523 	Dwarf_Die cu_die, var_die;
1524 	Dwarf_Die *scopes = NULL;
1525 	int reg, offset = loc->offset;
1526 	int ret = -1;
1527 	int i, nr_scopes;
1528 	int fbreg = -1;
1529 	int fb_offset = 0;
1530 	bool is_fbreg = false;
1531 	bool found = false;
1532 	u64 pc;
1533 	char buf[64];
1534 	enum type_match_result result = PERF_TMR_UNKNOWN;
1535 	const char *offset_sign = "";
1536 
1537 	if (dloc->op->multi_regs)
1538 		snprintf(buf, sizeof(buf), "reg%d, reg%d", dloc->op->reg1, dloc->op->reg2);
1539 	else if (dloc->op->reg1 == DWARF_REG_PC)
1540 		snprintf(buf, sizeof(buf), "PC");
1541 	else
1542 		snprintf(buf, sizeof(buf), "reg%d", dloc->op->reg1);
1543 
1544 	if (offset < 0) {
1545 		offset = -offset;
1546 		offset_sign = "-";
1547 	}
1548 
1549 	pr_debug_dtp("-----------------------------------------------------------\n");
1550 	pr_debug_dtp("find data type for %s%#x(%s) at %s+%#"PRIx64"\n",
1551 		     offset_sign, offset, buf,
1552 		     dloc->ms->sym->name, dloc->ip - dloc->ms->sym->start);
1553 
1554 	/*
1555 	 * IP is a relative instruction address from the start of the map, as
1556 	 * it can be randomized/relocated, it needs to translate to PC which is
1557 	 * a file address for DWARF processing.
1558 	 */
1559 	pc = map__rip_2objdump(dloc->ms->map, dloc->ip);
1560 
1561 	/* Get a compile_unit for this address */
1562 	if (!find_cu_die(dloc->di, pc, &cu_die)) {
1563 		pr_debug_dtp("cannot find CU for address %"PRIx64"\n", pc);
1564 		ann_data_stat.no_cuinfo++;
1565 		return -1;
1566 	}
1567 
1568 	reg = loc->reg1;
1569 	offset = loc->offset;
1570 
1571 	pr_debug_dtp("CU for %s (die:%#lx)\n",
1572 		     dwarf_diename(&cu_die), (long)dwarf_dieoffset(&cu_die));
1573 
1574 	if (reg == DWARF_REG_PC) {
1575 		if (get_global_var_type(&cu_die, dloc, dloc->ip, dloc->var_addr,
1576 					&offset, type_die)) {
1577 			dloc->type_offset = offset;
1578 
1579 			pr_debug_dtp("found by addr=%#"PRIx64" type_offset=%#x\n",
1580 				     dloc->var_addr, offset);
1581 			pr_debug_type_name(type_die, TSR_KIND_TYPE);
1582 			found = true;
1583 			goto out;
1584 		}
1585 	}
1586 
1587 	/* Get a list of nested scopes - i.e. (inlined) functions and blocks. */
1588 	nr_scopes = die_get_scopes(&cu_die, pc, &scopes);
1589 
1590 	if (reg != DWARF_REG_PC && dwarf_hasattr(&scopes[0], DW_AT_frame_base)) {
1591 		Dwarf_Attribute attr;
1592 		Dwarf_Block block;
1593 
1594 		/* Check if the 'reg' is assigned as frame base register */
1595 		if (dwarf_attr(&scopes[0], DW_AT_frame_base, &attr) != NULL &&
1596 		    dwarf_formblock(&attr, &block) == 0 && block.length == 1) {
1597 			switch (*block.data) {
1598 			case DW_OP_reg0 ... DW_OP_reg31:
1599 				fbreg = dloc->fbreg = *block.data - DW_OP_reg0;
1600 				break;
1601 			case DW_OP_call_frame_cfa:
1602 				dloc->fb_cfa = true;
1603 				if (die_get_cfa(dloc->di->dbg, pc, &fbreg,
1604 						&fb_offset) < 0)
1605 					fbreg = -1;
1606 				break;
1607 			default:
1608 				break;
1609 			}
1610 
1611 			pr_debug_dtp("frame base: cfa=%d fbreg=%d\n",
1612 				     dloc->fb_cfa, fbreg);
1613 		}
1614 	}
1615 
1616 retry:
1617 	is_fbreg = (reg == fbreg);
1618 	if (is_fbreg)
1619 		offset = loc->offset - fb_offset;
1620 
1621 	/* Search from the inner-most scope to the outer */
1622 	for (i = nr_scopes - 1; i >= 0; i--) {
1623 		Dwarf_Die mem_die;
1624 		int type_offset = offset;
1625 
1626 		if (reg == DWARF_REG_PC) {
1627 			if (!die_find_variable_by_addr(&scopes[i], dloc->var_addr,
1628 						       &var_die, &mem_die,
1629 						       &type_offset))
1630 				continue;
1631 		} else {
1632 			/* Look up variables/parameters in this scope */
1633 			if (!die_find_variable_by_reg(&scopes[i], pc, reg,
1634 						      &mem_die, &type_offset, is_fbreg, &var_die))
1635 				continue;
1636 		}
1637 
1638 		pr_debug_dtp("found \"%s\" (die: %#lx) in scope=%d/%d (die: %#lx) ",
1639 			     dwarf_diename(&var_die), (long)dwarf_dieoffset(&var_die),
1640 			     i+1, nr_scopes, (long)dwarf_dieoffset(&scopes[i]));
1641 
1642 		if (reg == DWARF_REG_PC) {
1643 			pr_debug_dtp("addr=%#"PRIx64" type_offset=%#x\n",
1644 				     dloc->var_addr, type_offset);
1645 		} else if (reg == DWARF_REG_FB || is_fbreg) {
1646 			pr_debug_dtp("stack_offset=%#x type_offset=%#x\n",
1647 				     fb_offset, type_offset);
1648 		} else {
1649 			pr_debug_dtp("type_offset=%#x\n", type_offset);
1650 		}
1651 
1652 		if (!found || dloc->type_offset < type_offset ||
1653 		    (dloc->type_offset == type_offset &&
1654 		     !is_better_type(&mem_die, type_die))) {
1655 			*type_die = mem_die;
1656 			dloc->type_offset = type_offset;
1657 			found = true;
1658 		}
1659 
1660 		pr_debug_location(&var_die, pc, reg);
1661 		pr_debug_type_name(&mem_die, TSR_KIND_TYPE);
1662 	}
1663 
1664 	if (!found && loc->multi_regs && reg == loc->reg1 && loc->reg1 != loc->reg2) {
1665 		reg = loc->reg2;
1666 		goto retry;
1667 	}
1668 
1669 	if (!found && reg != DWARF_REG_PC) {
1670 		result = find_data_type_block(dloc, &cu_die, scopes,
1671 					      nr_scopes, type_die);
1672 		if (result == PERF_TMR_OK) {
1673 			ann_data_stat.insn_track++;
1674 			found = true;
1675 		}
1676 	}
1677 
1678 out:
1679 	pr_debug_dtp("final result: ");
1680 	if (found) {
1681 		pr_debug_type_name(type_die, TSR_KIND_TYPE);
1682 		ret = 0;
1683 	} else {
1684 		switch (result) {
1685 		case PERF_TMR_NO_TYPE:
1686 		case PERF_TMR_NO_POINTER:
1687 			pr_debug_dtp("%s\n", match_result_str(result));
1688 			ann_data_stat.no_typeinfo++;
1689 			break;
1690 		case PERF_TMR_NO_SIZE:
1691 			pr_debug_dtp("%s\n", match_result_str(result));
1692 			ann_data_stat.invalid_size++;
1693 			break;
1694 		case PERF_TMR_BAD_OFFSET:
1695 			pr_debug_dtp("%s\n", match_result_str(result));
1696 			ann_data_stat.bad_offset++;
1697 			break;
1698 		case PERF_TMR_UNKNOWN:
1699 		case PERF_TMR_BAIL_OUT:
1700 		case PERF_TMR_OK:  /* should not reach here */
1701 		default:
1702 			pr_debug_dtp("no variable found\n");
1703 			ann_data_stat.no_var++;
1704 			break;
1705 		}
1706 		ret = -1;
1707 	}
1708 
1709 	free(scopes);
1710 	return ret;
1711 }
1712 
1713 /**
1714  * find_data_type - Return a data type at the location
1715  * @dloc: data location
1716  *
1717  * This functions searches the debug information of the binary to get the data
1718  * type it accesses.  The exact location is expressed by (ip, reg, offset)
1719  * for pointer variables or (ip, addr) for global variables.  Note that global
1720  * variables might update the @dloc->type_offset after finding the start of the
1721  * variable.  If it cannot find a global variable by address, it tried to find
1722  * a declaration of the variable using var_name.  In that case, @dloc->offset
1723  * won't be updated.
1724  *
1725  * It return %NULL if not found.
1726  */
1727 struct annotated_data_type *find_data_type(struct data_loc_info *dloc)
1728 {
1729 	struct dso *dso = map__dso(dloc->ms->map);
1730 	Dwarf_Die type_die;
1731 
1732 	/*
1733 	 * The type offset is the same as instruction offset by default.
1734 	 * But when finding a global variable, the offset won't be valid.
1735 	 */
1736 	dloc->type_offset = dloc->op->offset;
1737 
1738 	dloc->fbreg = -1;
1739 
1740 	if (find_data_type_die(dloc, &type_die) < 0)
1741 		return NULL;
1742 
1743 	return dso__findnew_data_type(dso, &type_die);
1744 }
1745 
1746 static int alloc_data_type_histograms(struct annotated_data_type *adt, int nr_entries)
1747 {
1748 	int i;
1749 	size_t sz = sizeof(struct type_hist);
1750 
1751 	sz += sizeof(struct type_hist_entry) * adt->self.size;
1752 
1753 	/* Allocate a table of pointers for each event */
1754 	adt->histograms = calloc(nr_entries, sizeof(*adt->histograms));
1755 	if (adt->histograms == NULL)
1756 		return -ENOMEM;
1757 
1758 	/*
1759 	 * Each histogram is allocated for the whole size of the type.
1760 	 * TODO: Probably we can move the histogram to members.
1761 	 */
1762 	for (i = 0; i < nr_entries; i++) {
1763 		adt->histograms[i] = zalloc(sz);
1764 		if (adt->histograms[i] == NULL)
1765 			goto err;
1766 	}
1767 
1768 	adt->nr_histograms = nr_entries;
1769 	return 0;
1770 
1771 err:
1772 	while (--i >= 0)
1773 		zfree(&(adt->histograms[i]));
1774 	zfree(&adt->histograms);
1775 	return -ENOMEM;
1776 }
1777 
1778 static void delete_data_type_histograms(struct annotated_data_type *adt)
1779 {
1780 	for (int i = 0; i < adt->nr_histograms; i++)
1781 		zfree(&(adt->histograms[i]));
1782 
1783 	zfree(&adt->histograms);
1784 	adt->nr_histograms = 0;
1785 }
1786 
1787 void annotated_data_type__tree_delete(struct rb_root *root)
1788 {
1789 	struct annotated_data_type *pos;
1790 
1791 	while (!RB_EMPTY_ROOT(root)) {
1792 		struct rb_node *node = rb_first(root);
1793 
1794 		rb_erase(node, root);
1795 		pos = rb_entry(node, struct annotated_data_type, node);
1796 		delete_members(&pos->self);
1797 		delete_data_type_histograms(pos);
1798 		zfree(&pos->self.type_name);
1799 		free(pos);
1800 	}
1801 }
1802 
1803 /**
1804  * annotated_data_type__update_samples - Update histogram
1805  * @adt: Data type to update
1806  * @evsel: Event to update
1807  * @offset: Offset in the type
1808  * @nr_samples: Number of samples at this offset
1809  * @period: Event count at this offset
1810  *
1811  * This function updates type histogram at @ofs for @evsel.  Samples are
1812  * aggregated before calling this function so it can be called with more
1813  * than one samples at a certain offset.
1814  */
1815 int annotated_data_type__update_samples(struct annotated_data_type *adt,
1816 					struct evsel *evsel, int offset,
1817 					int nr_samples, u64 period)
1818 {
1819 	struct type_hist *h;
1820 
1821 	if (adt == NULL)
1822 		return 0;
1823 
1824 	if (adt->histograms == NULL) {
1825 		int nr = evsel->evlist->core.nr_entries;
1826 
1827 		if (alloc_data_type_histograms(adt, nr) < 0)
1828 			return -1;
1829 	}
1830 
1831 	if (offset < 0 || offset >= adt->self.size)
1832 		return -1;
1833 
1834 	h = adt->histograms[evsel->core.idx];
1835 
1836 	h->nr_samples += nr_samples;
1837 	h->addr[offset].nr_samples += nr_samples;
1838 	h->period += period;
1839 	h->addr[offset].period += period;
1840 	return 0;
1841 }
1842 
1843 static void print_annotated_data_header(struct hist_entry *he, struct evsel *evsel)
1844 {
1845 	struct dso *dso = map__dso(he->ms.map);
1846 	int nr_members = 1;
1847 	int nr_samples = he->stat.nr_events;
1848 	int width = 7;
1849 	const char *val_hdr = "Percent";
1850 
1851 	if (evsel__is_group_event(evsel)) {
1852 		struct hist_entry *pair;
1853 
1854 		list_for_each_entry(pair, &he->pairs.head, pairs.node)
1855 			nr_samples += pair->stat.nr_events;
1856 	}
1857 
1858 	printf("Annotate type: '%s' in %s (%d samples):\n",
1859 	       he->mem_type->self.type_name, dso__name(dso), nr_samples);
1860 
1861 	if (evsel__is_group_event(evsel)) {
1862 		struct evsel *pos;
1863 		int i = 0;
1864 
1865 		nr_members = 0;
1866 		for_each_group_evsel(pos, evsel) {
1867 			if (symbol_conf.skip_empty &&
1868 			    evsel__hists(pos)->stats.nr_samples == 0)
1869 				continue;
1870 
1871 			printf(" event[%d] = %s\n", i++, pos->name);
1872 			nr_members++;
1873 		}
1874 	}
1875 
1876 	if (symbol_conf.show_total_period) {
1877 		width = 11;
1878 		val_hdr = "Period";
1879 	} else if (symbol_conf.show_nr_samples) {
1880 		width = 7;
1881 		val_hdr = "Samples";
1882 	}
1883 
1884 	printf("============================================================================\n");
1885 	printf("%*s %10s %10s  %s\n", (width + 1) * nr_members, val_hdr,
1886 	       "offset", "size", "field");
1887 }
1888 
1889 static void print_annotated_data_value(struct type_hist *h, u64 period, int nr_samples)
1890 {
1891 	double percent = h->period ? (100.0 * period / h->period) : 0;
1892 	const char *color = get_percent_color(percent);
1893 
1894 	if (symbol_conf.show_total_period)
1895 		color_fprintf(stdout, color, " %11" PRIu64, period);
1896 	else if (symbol_conf.show_nr_samples)
1897 		color_fprintf(stdout, color, " %7d", nr_samples);
1898 	else
1899 		color_fprintf(stdout, color, " %7.2f", percent);
1900 }
1901 
1902 static void print_annotated_data_type(struct annotated_data_type *mem_type,
1903 				      struct annotated_member *member,
1904 				      struct evsel *evsel, int indent)
1905 {
1906 	struct annotated_member *child;
1907 	struct type_hist *h = mem_type->histograms[evsel->core.idx];
1908 	int i, nr_events = 0, samples = 0;
1909 	u64 period = 0;
1910 	int width = symbol_conf.show_total_period ? 11 : 7;
1911 	struct evsel *pos;
1912 
1913 	for_each_group_evsel(pos, evsel) {
1914 		h = mem_type->histograms[pos->core.idx];
1915 
1916 		if (symbol_conf.skip_empty &&
1917 		    evsel__hists(pos)->stats.nr_samples == 0)
1918 			continue;
1919 
1920 		samples = 0;
1921 		period = 0;
1922 		for (i = 0; i < member->size; i++) {
1923 			samples += h->addr[member->offset + i].nr_samples;
1924 			period += h->addr[member->offset + i].period;
1925 		}
1926 		print_annotated_data_value(h, period, samples);
1927 		nr_events++;
1928 	}
1929 
1930 	printf(" %#10x %#10x  %*s%s\t%s",
1931 	       member->offset, member->size, indent, "", member->type_name,
1932 	       member->var_name ?: "");
1933 
1934 	if (!list_empty(&member->children))
1935 		printf(" {\n");
1936 
1937 	list_for_each_entry(child, &member->children, node)
1938 		print_annotated_data_type(mem_type, child, evsel, indent + 4);
1939 
1940 	if (!list_empty(&member->children))
1941 		printf("%*s}", (width + 1) * nr_events + 24 + indent, "");
1942 	printf(";\n");
1943 }
1944 
1945 int hist_entry__annotate_data_tty(struct hist_entry *he, struct evsel *evsel)
1946 {
1947 	print_annotated_data_header(he, evsel);
1948 	print_annotated_data_type(he->mem_type, &he->mem_type->self, evsel, 0);
1949 	printf("\n");
1950 
1951 	/* move to the next entry */
1952 	return '>';
1953 }
1954