| /* Native-dependent code for OpenBSD/amd64. |
| |
| Copyright (C) 2003-2021 Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| |
| #include "defs.h" |
| #include "gdbcore.h" |
| #include "regcache.h" |
| #include "target.h" |
| |
| #include "amd64-tdep.h" |
| #include "amd64-bsd-nat.h" |
| #include "amd64-nat.h" |
| #include "obsd-nat.h" |
| |
| /* Mapping between the general-purpose registers in OpenBSD/amd64 |
| `struct reg' format and GDB's register cache layout for |
| OpenBSD/i386. |
| |
| Note that most (if not all) OpenBSD/amd64 registers are 64-bit, |
| while the OpenBSD/i386 registers are all 32-bit, but since we're |
| little-endian we get away with that. */ |
| |
| /* From <machine/reg.h>. */ |
| static int amd64obsd32_r_reg_offset[] = |
| { |
| 14 * 8, /* %eax */ |
| 3 * 8, /* %ecx */ |
| 2 * 8, /* %edx */ |
| 13 * 8, /* %ebx */ |
| 15 * 8, /* %esp */ |
| 12 * 8, /* %ebp */ |
| 1 * 8, /* %esi */ |
| 0 * 8, /* %edi */ |
| 16 * 8, /* %eip */ |
| 17 * 8, /* %eflags */ |
| 18 * 8, /* %cs */ |
| 19 * 8, /* %ss */ |
| 20 * 8, /* %ds */ |
| 21 * 8, /* %es */ |
| 22 * 8, /* %fs */ |
| 23 * 8 /* %gs */ |
| }; |
| |
| |
| /* Support for debugging kernel virtual memory images. */ |
| |
| #include <sys/types.h> |
| #include <machine/frame.h> |
| #include <machine/pcb.h> |
| |
| #include "bsd-kvm.h" |
| |
| static int |
| amd64obsd_supply_pcb (struct regcache *regcache, struct pcb *pcb) |
| { |
| struct switchframe sf; |
| int regnum; |
| |
| /* The following is true for OpenBSD 3.5: |
| |
| The pcb contains the stack pointer at the point of the context |
| switch in cpu_switch(). At that point we have a stack frame as |
| described by `struct switchframe', which for OpenBSD 3.5 has the |
| following layout: |
| |
| interrupt level |
| %r15 |
| %r14 |
| %r13 |
| %r12 |
| %rbp |
| %rbx |
| return address |
| |
| Together with %rsp in the pcb, this accounts for all callee-saved |
| registers specified by the psABI. From this information we |
| reconstruct the register state as it would look when we just |
| returned from cpu_switch(). |
| |
| For core dumps the pcb is saved by savectx(). In that case the |
| stack frame only contains the return address, and there is no way |
| to recover the other registers. */ |
| |
| /* The stack pointer shouldn't be zero. */ |
| if (pcb->pcb_rsp == 0) |
| return 0; |
| |
| /* Read the stack frame, and check its validity. */ |
| read_memory (pcb->pcb_rsp, (gdb_byte *) &sf, sizeof sf); |
| if (sf.sf_rbp == pcb->pcb_rbp) |
| { |
| /* Yes, we have a frame that matches cpu_switch(). */ |
| pcb->pcb_rsp += sizeof (struct switchframe); |
| regcache->raw_supply (12, &sf.sf_r12); |
| regcache->raw_supply (13, &sf.sf_r13); |
| regcache->raw_supply (14, &sf.sf_r14); |
| regcache->raw_supply (15, &sf.sf_r15); |
| regcache->raw_supply (AMD64_RBX_REGNUM, &sf.sf_rbx); |
| regcache->raw_supply (AMD64_RIP_REGNUM, &sf.sf_rip); |
| } |
| else |
| { |
| /* No, the pcb must have been last updated by savectx(). */ |
| pcb->pcb_rsp += 8; |
| regcache->raw_supply (AMD64_RIP_REGNUM, &sf); |
| } |
| |
| regcache->raw_supply (AMD64_RSP_REGNUM, &pcb->pcb_rsp); |
| regcache->raw_supply (AMD64_RBP_REGNUM, &pcb->pcb_rbp); |
| |
| return 1; |
| } |
| |
| static amd64_bsd_nat_target<obsd_nat_target> the_amd64_obsd_nat_target; |
| |
| void _initialize_amd64obsd_nat (); |
| void |
| _initialize_amd64obsd_nat () |
| { |
| amd64_native_gregset32_reg_offset = amd64obsd32_r_reg_offset; |
| amd64_native_gregset32_num_regs = ARRAY_SIZE (amd64obsd32_r_reg_offset); |
| amd64_native_gregset64_reg_offset = amd64obsd_r_reg_offset; |
| |
| add_inf_child_target (&the_amd64_obsd_nat_target); |
| |
| /* Support debugging kernel virtual memory images. */ |
| bsd_kvm_add_target (amd64obsd_supply_pcb); |
| } |