| /* Target-dependent code for OpenBSD/sparc64. |
| |
| Copyright (C) 2004-2024 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 "extract-store-integer.h" |
| #include "frame.h" |
| #include "frame-unwind.h" |
| #include "gdbcore.h" |
| #include "osabi.h" |
| #include "regcache.h" |
| #include "regset.h" |
| #include "symtab.h" |
| #include "objfiles.h" |
| #include "trad-frame.h" |
| #include "inferior.h" |
| |
| #include "obsd-tdep.h" |
| #include "sparc64-tdep.h" |
| #include "solib-svr4.h" |
| #include "bsd-uthread.h" |
| |
| /* Older OpenBSD versions used the traditional NetBSD core file |
| format, even for ports that use ELF. These core files don't use |
| multiple register sets. Instead, the general-purpose and |
| floating-point registers are lumped together in a single section. |
| Unlike on NetBSD, OpenBSD uses a different layout for its |
| general-purpose registers than the layout used for ptrace(2). |
| |
| Newer OpenBSD versions use ELF core files. Here the register sets |
| match the ptrace(2) layout. */ |
| |
| /* From <machine/reg.h>. */ |
| const struct sparc_gregmap sparc64obsd_gregmap = |
| { |
| 0 * 8, /* "tstate" */ |
| 1 * 8, /* %pc */ |
| 2 * 8, /* %npc */ |
| 3 * 8, /* %y */ |
| -1, /* %fprs */ |
| -1, |
| 5 * 8, /* %g1 */ |
| 20 * 8, /* %l0 */ |
| 4 /* sizeof (%y) */ |
| }; |
| |
| const struct sparc_gregmap sparc64obsd_core_gregmap = |
| { |
| 0 * 8, /* "tstate" */ |
| 1 * 8, /* %pc */ |
| 2 * 8, /* %npc */ |
| 3 * 8, /* %y */ |
| -1, /* %fprs */ |
| -1, |
| 7 * 8, /* %g1 */ |
| 22 * 8, /* %l0 */ |
| 4 /* sizeof (%y) */ |
| }; |
| |
| static void |
| sparc64obsd_supply_gregset (const struct regset *regset, |
| struct regcache *regcache, |
| int regnum, const void *gregs, size_t len) |
| { |
| const void *fpregs = (char *)gregs + 288; |
| |
| if (len < 832) |
| { |
| sparc64_supply_gregset (&sparc64obsd_gregmap, regcache, regnum, gregs); |
| return; |
| } |
| |
| sparc64_supply_gregset (&sparc64obsd_core_gregmap, regcache, regnum, gregs); |
| sparc64_supply_fpregset (&sparc64_bsd_fpregmap, regcache, regnum, fpregs); |
| } |
| |
| static void |
| sparc64obsd_supply_fpregset (const struct regset *regset, |
| struct regcache *regcache, |
| int regnum, const void *fpregs, size_t len) |
| { |
| sparc64_supply_fpregset (&sparc64_bsd_fpregmap, regcache, regnum, fpregs); |
| } |
| |
| |
| /* Signal trampolines. */ |
| |
| /* Since OpenBSD 3.2, the sigtramp routine is mapped at a random page |
| in virtual memory. The randomness makes it somewhat tricky to |
| detect it, but fortunately we can rely on the fact that the start |
| of the sigtramp routine is page-aligned. We recognize the |
| trampoline by looking for the code that invokes the sigreturn |
| system call. The offset where we can find that code varies from |
| release to release. |
| |
| By the way, the mapping mentioned above is read-only, so you cannot |
| place a breakpoint in the signal trampoline. */ |
| |
| /* Default page size. */ |
| static const int sparc64obsd_page_size = 8192; |
| |
| /* Offset for sigreturn(2). */ |
| static const int sparc64obsd_sigreturn_offset[] = { |
| 0xf0, /* OpenBSD 3.8 */ |
| 0xec, /* OpenBSD 3.6 */ |
| 0xe8, /* OpenBSD 3.2 */ |
| -1 |
| }; |
| |
| static int |
| sparc64obsd_pc_in_sigtramp (CORE_ADDR pc, const char *name) |
| { |
| CORE_ADDR start_pc = (pc & ~(sparc64obsd_page_size - 1)); |
| unsigned long insn; |
| const int *offset; |
| |
| if (name) |
| return 0; |
| |
| for (offset = sparc64obsd_sigreturn_offset; *offset != -1; offset++) |
| { |
| /* Check for "restore %g0, SYS_sigreturn, %g1". */ |
| insn = sparc_fetch_instruction (start_pc + *offset); |
| if (insn != 0x83e82067) |
| continue; |
| |
| /* Check for "t ST_SYSCALL". */ |
| insn = sparc_fetch_instruction (start_pc + *offset + 8); |
| if (insn != 0x91d02000) |
| continue; |
| |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| static struct sparc_frame_cache * |
| sparc64obsd_frame_cache (const frame_info_ptr &this_frame, void **this_cache) |
| { |
| struct sparc_frame_cache *cache; |
| CORE_ADDR addr; |
| |
| if (*this_cache) |
| return (struct sparc_frame_cache *) *this_cache; |
| |
| cache = sparc_frame_cache (this_frame, this_cache); |
| gdb_assert (cache == *this_cache); |
| |
| /* If we couldn't find the frame's function, we're probably dealing |
| with an on-stack signal trampoline. */ |
| if (cache->pc == 0) |
| { |
| cache->pc = get_frame_pc (this_frame); |
| cache->pc &= ~(sparc64obsd_page_size - 1); |
| |
| /* Since we couldn't find the frame's function, the cache was |
| initialized under the assumption that we're frameless. */ |
| sparc_record_save_insn (cache); |
| addr = get_frame_register_unsigned (this_frame, SPARC_FP_REGNUM); |
| if (addr & 1) |
| addr += BIAS; |
| cache->base = addr; |
| } |
| |
| /* We find the appropriate instance of `struct sigcontext' at a |
| fixed offset in the signal frame. */ |
| addr = cache->base + 128 + 16; |
| cache->saved_regs = sparc64nbsd_sigcontext_saved_regs (addr, this_frame); |
| |
| return cache; |
| } |
| |
| static void |
| sparc64obsd_frame_this_id (const frame_info_ptr &this_frame, void **this_cache, |
| struct frame_id *this_id) |
| { |
| struct sparc_frame_cache *cache = |
| sparc64obsd_frame_cache (this_frame, this_cache); |
| |
| (*this_id) = frame_id_build (cache->base, cache->pc); |
| } |
| |
| static struct value * |
| sparc64obsd_frame_prev_register (const frame_info_ptr &this_frame, |
| void **this_cache, int regnum) |
| { |
| struct sparc_frame_cache *cache = |
| sparc64obsd_frame_cache (this_frame, this_cache); |
| |
| return trad_frame_get_prev_register (this_frame, cache->saved_regs, regnum); |
| } |
| |
| static int |
| sparc64obsd_sigtramp_frame_sniffer (const struct frame_unwind *self, |
| const frame_info_ptr &this_frame, |
| void **this_cache) |
| { |
| CORE_ADDR pc = get_frame_pc (this_frame); |
| const char *name; |
| |
| find_pc_partial_function (pc, &name, NULL, NULL); |
| if (sparc64obsd_pc_in_sigtramp (pc, name)) |
| return 1; |
| |
| return 0; |
| } |
| |
| static const struct frame_unwind sparc64obsd_frame_unwind = |
| { |
| "sparc64 openbsd sigtramp", |
| SIGTRAMP_FRAME, |
| default_frame_unwind_stop_reason, |
| sparc64obsd_frame_this_id, |
| sparc64obsd_frame_prev_register, |
| NULL, |
| sparc64obsd_sigtramp_frame_sniffer |
| }; |
| |
| /* Kernel debugging support. */ |
| |
| static struct sparc_frame_cache * |
| sparc64obsd_trapframe_cache (const frame_info_ptr &this_frame, void **this_cache) |
| { |
| struct sparc_frame_cache *cache; |
| CORE_ADDR sp, trapframe_addr; |
| int regnum; |
| |
| if (*this_cache) |
| return (struct sparc_frame_cache *) *this_cache; |
| |
| cache = sparc_frame_cache (this_frame, this_cache); |
| gdb_assert (cache == *this_cache); |
| |
| sp = get_frame_register_unsigned (this_frame, SPARC_SP_REGNUM); |
| trapframe_addr = sp + BIAS + 176; |
| |
| cache->saved_regs = trad_frame_alloc_saved_regs (this_frame); |
| |
| cache->saved_regs[SPARC64_STATE_REGNUM].set_addr (trapframe_addr); |
| cache->saved_regs[SPARC64_PC_REGNUM].set_addr (trapframe_addr + 8); |
| cache->saved_regs[SPARC64_NPC_REGNUM].set_addr (trapframe_addr + 16); |
| |
| for (regnum = SPARC_G0_REGNUM; regnum <= SPARC_I7_REGNUM; regnum++) |
| cache->saved_regs[regnum].set_addr (trapframe_addr + 48 |
| + (regnum - SPARC_G0_REGNUM) * 8); |
| |
| return cache; |
| } |
| |
| static void |
| sparc64obsd_trapframe_this_id (const frame_info_ptr &this_frame, |
| void **this_cache, struct frame_id *this_id) |
| { |
| struct sparc_frame_cache *cache = |
| sparc64obsd_trapframe_cache (this_frame, this_cache); |
| |
| (*this_id) = frame_id_build (cache->base, cache->pc); |
| } |
| |
| static struct value * |
| sparc64obsd_trapframe_prev_register (const frame_info_ptr &this_frame, |
| void **this_cache, int regnum) |
| { |
| struct sparc_frame_cache *cache = |
| sparc64obsd_trapframe_cache (this_frame, this_cache); |
| |
| return trad_frame_get_prev_register (this_frame, cache->saved_regs, regnum); |
| } |
| |
| static int |
| sparc64obsd_trapframe_sniffer (const struct frame_unwind *self, |
| const frame_info_ptr &this_frame, |
| void **this_cache) |
| { |
| CORE_ADDR pc; |
| ULONGEST pstate; |
| const char *name; |
| |
| /* Check whether we are in privileged mode, and bail out if we're not. */ |
| pstate = get_frame_register_unsigned (this_frame, SPARC64_PSTATE_REGNUM); |
| if ((pstate & SPARC64_PSTATE_PRIV) == 0) |
| return 0; |
| |
| pc = get_frame_address_in_block (this_frame); |
| find_pc_partial_function (pc, &name, NULL, NULL); |
| if (name && strcmp (name, "Lslowtrap_reenter") == 0) |
| return 1; |
| |
| return 0; |
| } |
| |
| static const struct frame_unwind sparc64obsd_trapframe_unwind = |
| { |
| "sparc64 openbsd trap", |
| NORMAL_FRAME, |
| default_frame_unwind_stop_reason, |
| sparc64obsd_trapframe_this_id, |
| sparc64obsd_trapframe_prev_register, |
| NULL, |
| sparc64obsd_trapframe_sniffer |
| }; |
| |
| |
| /* Threads support. */ |
| |
| /* Offset wthin the thread structure where we can find %fp and %i7. */ |
| #define SPARC64OBSD_UTHREAD_FP_OFFSET 232 |
| #define SPARC64OBSD_UTHREAD_PC_OFFSET 240 |
| |
| static void |
| sparc64obsd_supply_uthread (struct regcache *regcache, |
| int regnum, CORE_ADDR addr) |
| { |
| struct gdbarch *gdbarch = regcache->arch (); |
| enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| CORE_ADDR fp, fp_addr = addr + SPARC64OBSD_UTHREAD_FP_OFFSET; |
| gdb_byte buf[8]; |
| |
| /* This function calls functions that depend on the global current thread. */ |
| gdb_assert (regcache->ptid () == inferior_ptid); |
| |
| gdb_assert (regnum >= -1); |
| |
| fp = read_memory_unsigned_integer (fp_addr, 8, byte_order); |
| if (regnum == SPARC_SP_REGNUM || regnum == -1) |
| { |
| store_unsigned_integer (buf, 8, byte_order, fp); |
| regcache->raw_supply (SPARC_SP_REGNUM, buf); |
| |
| if (regnum == SPARC_SP_REGNUM) |
| return; |
| } |
| |
| if (regnum == SPARC64_PC_REGNUM || regnum == SPARC64_NPC_REGNUM |
| || regnum == -1) |
| { |
| CORE_ADDR i7, i7_addr = addr + SPARC64OBSD_UTHREAD_PC_OFFSET; |
| |
| i7 = read_memory_unsigned_integer (i7_addr, 8, byte_order); |
| if (regnum == SPARC64_PC_REGNUM || regnum == -1) |
| { |
| store_unsigned_integer (buf, 8, byte_order, i7 + 8); |
| regcache->raw_supply (SPARC64_PC_REGNUM, buf); |
| } |
| if (regnum == SPARC64_NPC_REGNUM || regnum == -1) |
| { |
| store_unsigned_integer (buf, 8, byte_order, i7 + 12); |
| regcache->raw_supply (SPARC64_NPC_REGNUM, buf); |
| } |
| |
| if (regnum == SPARC64_PC_REGNUM || regnum == SPARC64_NPC_REGNUM) |
| return; |
| } |
| |
| sparc_supply_rwindow (regcache, fp, regnum); |
| } |
| |
| static void |
| sparc64obsd_collect_uthread(const struct regcache *regcache, |
| int regnum, CORE_ADDR addr) |
| { |
| struct gdbarch *gdbarch = regcache->arch (); |
| enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| CORE_ADDR sp; |
| gdb_byte buf[8]; |
| |
| /* This function calls functions that depend on the global current thread. */ |
| gdb_assert (regcache->ptid () == inferior_ptid); |
| |
| gdb_assert (regnum >= -1); |
| |
| if (regnum == SPARC_SP_REGNUM || regnum == -1) |
| { |
| CORE_ADDR fp_addr = addr + SPARC64OBSD_UTHREAD_FP_OFFSET; |
| |
| regcache->raw_collect (SPARC_SP_REGNUM, buf); |
| write_memory (fp_addr,buf, 8); |
| } |
| |
| if (regnum == SPARC64_PC_REGNUM || regnum == -1) |
| { |
| CORE_ADDR i7, i7_addr = addr + SPARC64OBSD_UTHREAD_PC_OFFSET; |
| |
| regcache->raw_collect (SPARC64_PC_REGNUM, buf); |
| i7 = extract_unsigned_integer (buf, 8, byte_order) - 8; |
| write_memory_unsigned_integer (i7_addr, 8, byte_order, i7); |
| |
| if (regnum == SPARC64_PC_REGNUM) |
| return; |
| } |
| |
| regcache->raw_collect (SPARC_SP_REGNUM, buf); |
| sp = extract_unsigned_integer (buf, 8, byte_order); |
| sparc_collect_rwindow (regcache, sp, regnum); |
| } |
| |
| |
| static const struct regset sparc64obsd_gregset = |
| { |
| NULL, sparc64obsd_supply_gregset, NULL |
| }; |
| |
| static const struct regset sparc64obsd_fpregset = |
| { |
| NULL, sparc64obsd_supply_fpregset, NULL |
| }; |
| |
| static void |
| sparc64obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| { |
| sparc_gdbarch_tdep *tdep = gdbarch_tdep<sparc_gdbarch_tdep> (gdbarch); |
| |
| tdep->gregset = &sparc64obsd_gregset; |
| tdep->sizeof_gregset = 288; |
| tdep->fpregset = &sparc64obsd_fpregset; |
| tdep->sizeof_fpregset = 272; |
| |
| /* Make sure we can single-step "new" syscalls. */ |
| tdep->step_trap = sparcnbsd_step_trap; |
| |
| frame_unwind_append_unwinder (gdbarch, &sparc64obsd_frame_unwind); |
| frame_unwind_append_unwinder (gdbarch, &sparc64obsd_trapframe_unwind); |
| |
| sparc64_init_abi (info, gdbarch); |
| obsd_init_abi (info, gdbarch); |
| |
| /* OpenBSD/sparc64 has SVR4-style shared libraries. */ |
| set_solib_svr4_fetch_link_map_offsets |
| (gdbarch, svr4_lp64_fetch_link_map_offsets); |
| set_gdbarch_skip_solib_resolver (gdbarch, obsd_skip_solib_resolver); |
| |
| /* OpenBSD provides a user-level threads implementation. */ |
| bsd_uthread_set_supply_uthread (gdbarch, sparc64obsd_supply_uthread); |
| bsd_uthread_set_collect_uthread (gdbarch, sparc64obsd_collect_uthread); |
| } |
| |
| void _initialize_sparc64obsd_tdep (); |
| void |
| _initialize_sparc64obsd_tdep () |
| { |
| gdbarch_register_osabi (bfd_arch_sparc, bfd_mach_sparc_v9, |
| GDB_OSABI_OPENBSD, sparc64obsd_init_abi); |
| } |