/* Target-dependent code for NetBSD/amd64. Copyright (C) 2003-2023 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 . */ #include "defs.h" #include "arch-utils.h" #include "frame.h" #include "gdbcore.h" #include "osabi.h" #include "symtab.h" #include "amd64-tdep.h" #include "gdbsupport/x86-xstate.h" #include "netbsd-tdep.h" #include "solib-svr4.h" #include "trad-frame.h" #include "frame-unwind.h" /* Support for signal handlers. */ /* Return whether THIS_FRAME corresponds to a NetBSD sigtramp routine. */ static int amd64nbsd_sigtramp_p (frame_info_ptr this_frame) { CORE_ADDR pc = get_frame_pc (this_frame); const char *name; find_pc_partial_function (pc, &name, NULL, NULL); return nbsd_pc_in_sigtramp (pc, name); } /* Assuming THIS_FRAME corresponds to a NetBSD sigtramp routine, return the address of the associated mcontext structure. */ static CORE_ADDR amd64nbsd_mcontext_addr (frame_info_ptr this_frame) { CORE_ADDR addr; /* The register %r15 points at `struct ucontext' upon entry of a signal trampoline. */ addr = get_frame_register_unsigned (this_frame, AMD64_R15_REGNUM); /* The mcontext structure lives as offset 56 in `struct ucontext'. */ return addr + 56; } /* NetBSD 2.0 or later. */ /* Mapping between the general-purpose registers in `struct reg' format and GDB's register cache layout. */ /* From . */ int amd64nbsd_r_reg_offset[] = { 14 * 8, /* %rax */ 13 * 8, /* %rbx */ 3 * 8, /* %rcx */ 2 * 8, /* %rdx */ 1 * 8, /* %rsi */ 0 * 8, /* %rdi */ 12 * 8, /* %rbp */ 24 * 8, /* %rsp */ 4 * 8, /* %r8 .. */ 5 * 8, 6 * 8, 7 * 8, 8 * 8, 9 * 8, 10 * 8, 11 * 8, /* ... %r15 */ 21 * 8, /* %rip */ 23 * 8, /* %eflags */ 22 * 8, /* %cs */ 25 * 8, /* %ss */ 18 * 8, /* %ds */ 17 * 8, /* %es */ 16 * 8, /* %fs */ 15 * 8 /* %gs */ }; /* Kernel debugging support */ static const int amd64nbsd_tf_reg_offset[] = { 18 * 8, /* %rax */ 17 * 8, /* %rbx */ 10 * 8, /* %rcx */ 2 * 8, /* %rdx */ 1 * 8, /* %rsi */ 0 * 8, /* %rdi */ 16 * 8, /* %rbp */ 28 * 8, /* %rsp */ 4 * 8, /* %r8 .. */ 5 * 8, 3 * 8, 11 * 8, 12 * 8, 13 * 8, 14 * 8, 15 * 8, /* ... %r15 */ 25 * 8, /* %rip */ 27 * 8, /* %eflags */ 26 * 8, /* %cs */ 29 * 8, /* %ss */ 22 * 8, /* %ds */ 21 * 8, /* %es */ 20 * 8, /* %fs */ 19 * 8, /* %gs */ }; static struct trad_frame_cache * amd64nbsd_trapframe_cache(frame_info_ptr this_frame, void **this_cache) { struct trad_frame_cache *cache; CORE_ADDR func, sp, addr; ULONGEST cs = 0, rip = 0; const char *name; int i; struct gdbarch *gdbarch = get_frame_arch (this_frame); enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); if (*this_cache) return (struct trad_frame_cache *)*this_cache; cache = trad_frame_cache_zalloc (this_frame); *this_cache = cache; func = get_frame_func (this_frame); sp = get_frame_register_unsigned (this_frame, AMD64_RSP_REGNUM); find_pc_partial_function (func, &name, NULL, NULL); /* There is an extra 'call' in the interrupt sequence - ignore the extra * return address */ addr = sp; if (name) { if (strncmp (name, "Xintr", 5) == 0 || strncmp (name, "Xhandle", 7) == 0) { addr += 8; /* It's an interrupt frame. */ } } #ifdef DEBUG_TRAPFRAME for (i = 0; i < 50; i++) { cs = read_memory_unsigned_integer (addr + i * 8, 8, byte_order); printf("%s i=%d r=%#jx\n", name, i, (intmax_t)cs); } #endif for (i = 0; i < ARRAY_SIZE (amd64nbsd_tf_reg_offset); i++) if (amd64nbsd_tf_reg_offset[i] != -1) trad_frame_set_reg_addr (cache, i, addr + amd64nbsd_tf_reg_offset[i]); /* Read %cs and %rip when we have the addresses to hand */ cs = read_memory_unsigned_integer (addr + amd64nbsd_tf_reg_offset[AMD64_CS_REGNUM], 8, byte_order); rip = read_memory_unsigned_integer (addr + amd64nbsd_tf_reg_offset[AMD64_RIP_REGNUM], 8, byte_order); #ifdef DEBUG_TRAPFRAME printf("%s cs=%#jx rip=%#jx\n", name, (intmax_t)cs, (intmax_t)rip); #endif /* The trap frame layout was changed lf the %rip value is less than 2^16 it * is almost certainly the %ss of the old format. */ if (rip < (1 << 16)) { for (i = 0; i < ARRAY_SIZE (amd64nbsd_tf_reg_offset); i++) { if (amd64nbsd_tf_reg_offset[i] == -1) continue; trad_frame_set_reg_addr (cache, i, addr + amd64nbsd_r_reg_offset[i]); /* Read %cs when we have the address to hand */ if (i == AMD64_CS_REGNUM) cs = read_memory_unsigned_integer (addr + amd64nbsd_r_reg_offset[i], 8, byte_order); } } if ((cs & I386_SEL_RPL) == I386_SEL_UPL || (name && strncmp(name, "Xsoft", 5) == 0)) { /* Trap from user space or soft interrupt; terminate backtrace. */ trad_frame_set_id (cache, outer_frame_id); } else { /* Construct the frame ID using the function start. */ trad_frame_set_id (cache, frame_id_build (sp + 16, func)); } return cache; } static void amd64nbsd_trapframe_this_id (frame_info_ptr this_frame, void **this_cache, struct frame_id *this_id) { struct trad_frame_cache *cache = amd64nbsd_trapframe_cache (this_frame, this_cache); trad_frame_get_id (cache, this_id); } static struct value * amd64nbsd_trapframe_prev_register (frame_info_ptr this_frame, void **this_cache, int regnum) { struct trad_frame_cache *cache = amd64nbsd_trapframe_cache (this_frame, this_cache); return trad_frame_get_register (cache, this_frame, regnum); } static int amd64nbsd_trapframe_sniffer (const struct frame_unwind *self, frame_info_ptr this_frame, void **this_prologue_cache) { ULONGEST cs = 0; const char *name; try { cs = get_frame_register_unsigned (this_frame, AMD64_CS_REGNUM); } catch (const gdb_exception &except) { if (except.reason < 0 && except.error != NOT_AVAILABLE_ERROR) throw; } if ((cs & I386_SEL_RPL) == I386_SEL_UPL) return 0; find_pc_partial_function (get_frame_pc (this_frame), &name, NULL, NULL); return (name && ((strcmp (name, "alltraps") == 0) || (strcmp (name, "calltrap") == 0) || (strcmp (name, "handle_syscall") == 0) || (strcmp (name, "Xdoreti") == 0) || (strcmp (name, "Xspllower") == 0) || (strncmp (name, "Xhandle", 7) == 0) || (strncmp (name, "Xintr", 5) == 0) || (strncmp (name, "Xpreempt", 8) == 0) || (strncmp (name, "Xrecurse", 8) == 0) || (strncmp (name, "Xresume", 7) == 0) || (strncmp (name, "Xsoft", 5) == 0) || (strncmp (name, "Xstray", 6) == 0) || (strncmp (name, "Xsyscall", 8) == 0) || (strncmp (name, "Xtrap", 5) == 0) )); } static const struct frame_unwind amd64nbsd_trapframe_unwind = { /* FIXME: kettenis/20051219: This really is more like an interrupt frame, but SIGTRAMP_FRAME would print , which really is not what we want here. */ "amd64 trapframe", NORMAL_FRAME, default_frame_unwind_stop_reason, amd64nbsd_trapframe_this_id, amd64nbsd_trapframe_prev_register, NULL, amd64nbsd_trapframe_sniffer }; static void amd64nbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) { i386_gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); /* Initialize general-purpose register set details first. */ tdep->gregset_reg_offset = amd64nbsd_r_reg_offset; tdep->gregset_num_regs = ARRAY_SIZE (amd64nbsd_r_reg_offset); tdep->sizeof_gregset = 26 * 8; amd64_init_abi (info, gdbarch, amd64_target_description (X86_XSTATE_SSE_MASK, true)); nbsd_init_abi (info, gdbarch); tdep->jb_pc_offset = 7 * 8; /* NetBSD has its own convention for signal trampolines. */ tdep->sigtramp_p = amd64nbsd_sigtramp_p; tdep->sigcontext_addr = amd64nbsd_mcontext_addr; tdep->sc_reg_offset = amd64nbsd_r_reg_offset; tdep->sc_num_regs = ARRAY_SIZE (amd64nbsd_r_reg_offset); /* NetBSD uses SVR4-style shared libraries. */ set_solib_svr4_fetch_link_map_offsets (gdbarch, svr4_lp64_fetch_link_map_offsets); /* Unwind kernel trap frames correctly. */ frame_unwind_prepend_unwinder (gdbarch, &amd64nbsd_trapframe_unwind); } void _initialize_amd64nbsd_tdep (); void _initialize_amd64nbsd_tdep () { /* The NetBSD/amd64 native dependent code makes this assumption. */ gdb_assert (ARRAY_SIZE (amd64nbsd_r_reg_offset) == AMD64_NUM_GREGS); gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64, GDB_OSABI_NETBSD, amd64nbsd_init_abi); }