x86/util/unwind-libdw.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 #include <elfutils/libdwfl.h>
0003 #include "../../../util/unwind-libdw.h"
0004 #include "../../../util/perf_regs.h"
0005 #include "../../../util/event.h"
0006
0007 bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
0008 {
0009     struct unwind_info *ui = arg;
0010     struct regs_dump *user_regs = &ui->sample->user_regs;
0011     Dwarf_Word dwarf_regs[17];
0012     unsigned nregs;
0013
0014 #define REG(r) ({                       \
0015     Dwarf_Word val = 0;                 \
0016     perf_reg_value(&val, user_regs, PERF_REG_X86_##r);  \
0017     val;                            \
0018 })
0019
0020     if (user_regs->abi == PERF_SAMPLE_REGS_ABI_32) {
0021         dwarf_regs[0] = REG(AX);
0022         dwarf_regs[1] = REG(CX);
0023         dwarf_regs[2] = REG(DX);
0024         dwarf_regs[3] = REG(BX);
0025         dwarf_regs[4] = REG(SP);
0026         dwarf_regs[5] = REG(BP);
0027         dwarf_regs[6] = REG(SI);
0028         dwarf_regs[7] = REG(DI);
0029         dwarf_regs[8] = REG(IP);
0030         nregs = 9;
0031     } else {
0032         dwarf_regs[0]  = REG(AX);
0033         dwarf_regs[1]  = REG(DX);
0034         dwarf_regs[2]  = REG(CX);
0035         dwarf_regs[3]  = REG(BX);
0036         dwarf_regs[4]  = REG(SI);
0037         dwarf_regs[5]  = REG(DI);
0038         dwarf_regs[6]  = REG(BP);
0039         dwarf_regs[7]  = REG(SP);
0040         dwarf_regs[8]  = REG(R8);
0041         dwarf_regs[9]  = REG(R9);
0042         dwarf_regs[10] = REG(R10);
0043         dwarf_regs[11] = REG(R11);
0044         dwarf_regs[12] = REG(R12);
0045         dwarf_regs[13] = REG(R13);
0046         dwarf_regs[14] = REG(R14);
0047         dwarf_regs[15] = REG(R15);
0048         dwarf_regs[16] = REG(IP);
0049         nregs = 17;
0050     }
0051
0052     return dwfl_thread_state_registers(thread, 0, nregs, dwarf_regs);
0053 }