1// SPDX-License-Identifier: GPL-2.0
2#include <elfutils/libdwfl.h>
3#include <linux/kernel.h>
4#include "perf_regs.h"
5#include "../../../util/unwind-libdw.h"
6#include "../../../util/perf_regs.h"
7#include "../../../util/sample.h"
8
9/* See backends/ppc_initreg.c and backends/ppc_regs.c in elfutils. */
10static const int special_regs[3][2] = {
11 { 65, PERF_REG_POWERPC_LINK },
12 { 101, PERF_REG_POWERPC_XER },
13 { 109, PERF_REG_POWERPC_CTR },
14};
15
16bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
17{
18 struct unwind_info *ui = arg;
19 struct regs_dump *user_regs = perf_sample__user_regs(sample: ui->sample);
20 Dwarf_Word dwarf_regs[32], dwarf_nip;
21 size_t i;
22
23#define REG(r) ({ \
24 Dwarf_Word val = 0; \
25 perf_reg_value(&val, user_regs, PERF_REG_POWERPC_##r); \
26 val; \
27})
28
29 dwarf_regs[0] = REG(R0);
30 dwarf_regs[1] = REG(R1);
31 dwarf_regs[2] = REG(R2);
32 dwarf_regs[3] = REG(R3);
33 dwarf_regs[4] = REG(R4);
34 dwarf_regs[5] = REG(R5);
35 dwarf_regs[6] = REG(R6);
36 dwarf_regs[7] = REG(R7);
37 dwarf_regs[8] = REG(R8);
38 dwarf_regs[9] = REG(R9);
39 dwarf_regs[10] = REG(R10);
40 dwarf_regs[11] = REG(R11);
41 dwarf_regs[12] = REG(R12);
42 dwarf_regs[13] = REG(R13);
43 dwarf_regs[14] = REG(R14);
44 dwarf_regs[15] = REG(R15);
45 dwarf_regs[16] = REG(R16);
46 dwarf_regs[17] = REG(R17);
47 dwarf_regs[18] = REG(R18);
48 dwarf_regs[19] = REG(R19);
49 dwarf_regs[20] = REG(R20);
50 dwarf_regs[21] = REG(R21);
51 dwarf_regs[22] = REG(R22);
52 dwarf_regs[23] = REG(R23);
53 dwarf_regs[24] = REG(R24);
54 dwarf_regs[25] = REG(R25);
55 dwarf_regs[26] = REG(R26);
56 dwarf_regs[27] = REG(R27);
57 dwarf_regs[28] = REG(R28);
58 dwarf_regs[29] = REG(R29);
59 dwarf_regs[30] = REG(R30);
60 dwarf_regs[31] = REG(R31);
61 if (!dwfl_thread_state_registers(thread, 0, 32, dwarf_regs))
62 return false;
63
64 dwarf_nip = REG(NIP);
65 dwfl_thread_state_register_pc(thread, dwarf_nip);
66 for (i = 0; i < ARRAY_SIZE(special_regs); i++) {
67 Dwarf_Word val = 0;
68 perf_reg_value(&val, user_regs, special_regs[i][1]);
69 if (!dwfl_thread_state_registers(thread,
70 special_regs[i][0], 1,
71 &val))
72 return false;
73 }
74
75 return true;
76}
77

source code of linux/tools/perf/arch/powerpc/util/unwind-libdw.c