powerpc/util/unwind-libdw.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 #include <elfutils/libdwfl.h>
0003 #include <linux/kernel.h>
0004 #include "../../../util/unwind-libdw.h"
0005 #include "../../../util/perf_regs.h"
0006 #include "../../../util/event.h"
0007
0008 /* See backends/ppc_initreg.c and backends/ppc_regs.c in elfutils.  */
0009 static const int special_regs[3][2] = {
0010     { 65, PERF_REG_POWERPC_LINK },
0011     { 101, PERF_REG_POWERPC_XER },
0012     { 109, PERF_REG_POWERPC_CTR },
0013 };
0014
0015 bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
0016 {
0017     struct unwind_info *ui = arg;
0018     struct regs_dump *user_regs = &ui->sample->user_regs;
0019     Dwarf_Word dwarf_regs[32], dwarf_nip;
0020     size_t i;
0021
0022 #define REG(r) ({                       \
0023     Dwarf_Word val = 0;                 \
0024     perf_reg_value(&val, user_regs, PERF_REG_POWERPC_##r);  \
0025     val;                            \
0026 })
0027
0028     dwarf_regs[0]  = REG(R0);
0029     dwarf_regs[1]  = REG(R1);
0030     dwarf_regs[2]  = REG(R2);
0031     dwarf_regs[3]  = REG(R3);
0032     dwarf_regs[4]  = REG(R4);
0033     dwarf_regs[5]  = REG(R5);
0034     dwarf_regs[6]  = REG(R6);
0035     dwarf_regs[7]  = REG(R7);
0036     dwarf_regs[8]  = REG(R8);
0037     dwarf_regs[9]  = REG(R9);
0038     dwarf_regs[10] = REG(R10);
0039     dwarf_regs[11] = REG(R11);
0040     dwarf_regs[12] = REG(R12);
0041     dwarf_regs[13] = REG(R13);
0042     dwarf_regs[14] = REG(R14);
0043     dwarf_regs[15] = REG(R15);
0044     dwarf_regs[16] = REG(R16);
0045     dwarf_regs[17] = REG(R17);
0046     dwarf_regs[18] = REG(R18);
0047     dwarf_regs[19] = REG(R19);
0048     dwarf_regs[20] = REG(R20);
0049     dwarf_regs[21] = REG(R21);
0050     dwarf_regs[22] = REG(R22);
0051     dwarf_regs[23] = REG(R23);
0052     dwarf_regs[24] = REG(R24);
0053     dwarf_regs[25] = REG(R25);
0054     dwarf_regs[26] = REG(R26);
0055     dwarf_regs[27] = REG(R27);
0056     dwarf_regs[28] = REG(R28);
0057     dwarf_regs[29] = REG(R29);
0058     dwarf_regs[30] = REG(R30);
0059     dwarf_regs[31] = REG(R31);
0060     if (!dwfl_thread_state_registers(thread, 0, 32, dwarf_regs))
0061         return false;
0062
0063     dwarf_nip = REG(NIP);
0064     dwfl_thread_state_register_pc(thread, dwarf_nip);
0065     for (i = 0; i < ARRAY_SIZE(special_regs); i++) {
0066         Dwarf_Word val = 0;
0067         perf_reg_value(&val, user_regs, special_regs[i][1]);
0068         if (!dwfl_thread_state_registers(thread,
0069                          special_regs[i][0], 1,
0070                          &val))
0071             return false;
0072     }
0073
0074     return true;
0075 }