path: root/tools/perf/util/annotate-data.c

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Convert sample address to data type using DWARF debug info.
 *
 * Written by Namhyung Kim <namhyung@kernel.org>
 */

#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>

#include "annotate.h"
#include "annotate-data.h"
#include "debuginfo.h"
#include "debug.h"
#include "dso.h"
#include "dwarf-regs.h"
#include "evsel.h"
#include "evlist.h"
#include "map.h"
#include "map_symbol.h"
#include "strbuf.h"
#include "symbol.h"
#include "symbol_conf.h"
#include "thread.h"

#define pr_debug_dtp(fmt, ...)					\
do {								\
	if (debug_type_profile)					\
		pr_info(fmt, ##__VA_ARGS__);			\
	else							\
		pr_debug3(fmt, ##__VA_ARGS__);			\
} while (0)

static void pr_debug_type_name(Dwarf_Die *die)
{
	struct strbuf sb;
	char *str;

	if (!debug_type_profile && verbose < 3)
		return;

	strbuf_init(&sb, 32);
	die_get_typename_from_type(die, &sb);
	str = strbuf_detach(&sb, NULL);
	pr_info(" type=%s (die:%lx)\n", str, (long)dwarf_dieoffset(die));
	free(str);
}

/*
 * Type information in a register, valid when @ok is true.
 * The @caller_saved registers are invalidated after a function call.
 */
struct type_state_reg {
	Dwarf_Die type;
	bool ok;
	bool caller_saved;
};

/* Type information in a stack location, dynamically allocated */
struct type_state_stack {
	struct list_head list;
	Dwarf_Die type;
	int offset;
	int size;
	bool compound;
};

/* FIXME: This should be arch-dependent */
#define TYPE_STATE_MAX_REGS  16

/*
 * State table to maintain type info in each register and stack location.
 * It'll be updated when new variable is allocated or type info is moved
 * to a new location (register or stack).  As it'd be used with the
 * shortest path of basic blocks, it only maintains a single table.
 */
struct type_state {
	/* state of general purpose registers */
	struct type_state_reg regs[TYPE_STATE_MAX_REGS];
	/* state of stack location */
	struct list_head stack_vars;
	/* return value register */
	int ret_reg;
};

static bool has_reg_type(struct type_state *state, int reg)
{
	return (unsigned)reg < ARRAY_SIZE(state->regs);
}

static void init_type_state(struct type_state *state, struct arch *arch)
{
	memset(state, 0, sizeof(*state));
	INIT_LIST_HEAD(&state->stack_vars);

	if (arch__is(arch, "x86")) {
		state->regs[0].caller_saved = true;
		state->regs[1].caller_saved = true;
		state->regs[2].caller_saved = true;
		state->regs[4].caller_saved = true;
		state->regs[5].caller_saved = true;
		state->regs[8].caller_saved = true;
		state->regs[9].caller_saved = true;
		state->regs[10].caller_saved = true;
		state->regs[11].caller_saved = true;
		state->ret_reg = 0;
	}
}

static void exit_type_state(struct type_state *state)
{
	struct type_state_stack *stack, *tmp;

	list_for_each_entry_safe(stack, tmp, &state->stack_vars, list) {
		list_del(&stack->list);
		free(stack