| /* Target-dependent code for OpenBSD/sparc. |
| |
| Copyright (C) 2004, 2005 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 2 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, write to the Free Software |
| Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| Boston, MA 02110-1301, USA. */ |
| |
| #include "defs.h" |
| #include "floatformat.h" |
| #include "frame.h" |
| #include "frame-unwind.h" |
| #include "gdbcore.h" |
| #include "osabi.h" |
| #include "regcache.h" |
| #include "symtab.h" |
| #include "trad-frame.h" |
| |
| #include "gdb_assert.h" |
| |
| #include "obsd-tdep.h" |
| #include "sparc-tdep.h" |
| #include "solib-svr4.h" |
| #include "bsd-uthread.h" |
| |
| /* Signal trampolines. */ |
| |
| /* The OpenBSD kernel maps the signal trampoline at some random |
| location in user space, which means that the traditional BSD way of |
| detecting it won't work. |
| |
| The signal trampoline will be mapped at an address that is page |
| aligned. We recognize the signal trampoline by the looking for the |
| sigreturn system call. */ |
| |
| static const int sparc32obsd_page_size = 4096; |
| |
| static int |
| sparc32obsd_pc_in_sigtramp (CORE_ADDR pc, char *name) |
| { |
| CORE_ADDR start_pc = (pc & ~(sparc32obsd_page_size - 1)); |
| unsigned long insn; |
| |
| if (name) |
| return 0; |
| |
| /* Check for "restore %g0, SYS_sigreturn, %g1". */ |
| insn = sparc_fetch_instruction (start_pc + 0xec); |
| if (insn != 0x83e82067) |
| return 0; |
| |
| /* Check for "t ST_SYSCALL". */ |
| insn = sparc_fetch_instruction (start_pc + 0xf4); |
| if (insn != 0x91d02000) |
| return 0; |
| |
| return 1; |
| } |
| |
| static struct sparc_frame_cache * |
| sparc32obsd_frame_cache (struct frame_info *next_frame, void **this_cache) |
| { |
| struct sparc_frame_cache *cache; |
| CORE_ADDR addr; |
| |
| if (*this_cache) |
| return *this_cache; |
| |
| cache = sparc_frame_cache (next_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 = frame_pc_unwind (next_frame); |
| cache->pc &= ~(sparc32obsd_page_size - 1); |
| |
| /* Since we couldn't find the frame's function, the cache was |
| initialized under the assumption that we're frameless. */ |
| cache->frameless_p = 0; |
| addr = frame_unwind_register_unsigned (next_frame, SPARC_FP_REGNUM); |
| cache->base = addr; |
| } |
| |
| cache->saved_regs = sparc32nbsd_sigcontext_saved_regs (next_frame); |
| |
| return cache; |
| } |
| |
| static void |
| sparc32obsd_frame_this_id (struct frame_info *next_frame, void **this_cache, |
| struct frame_id *this_id) |
| { |
| struct sparc_frame_cache *cache = |
| sparc32obsd_frame_cache (next_frame, this_cache); |
| |
| (*this_id) = frame_id_build (cache->base, cache->pc); |
| } |
| |
| static void |
| sparc32obsd_frame_prev_register (struct frame_info *next_frame, |
| void **this_cache, |
| int regnum, int *optimizedp, |
| enum lval_type *lvalp, CORE_ADDR *addrp, |
| int *realnump, gdb_byte *valuep) |
| { |
| struct sparc_frame_cache *cache = |
| sparc32obsd_frame_cache (next_frame, this_cache); |
| |
| trad_frame_get_prev_register (next_frame, cache->saved_regs, regnum, |
| optimizedp, lvalp, addrp, realnump, valuep); |
| } |
| |
| static const struct frame_unwind sparc32obsd_frame_unwind = |
| { |
| SIGTRAMP_FRAME, |
| sparc32obsd_frame_this_id, |
| sparc32obsd_frame_prev_register |
| }; |
| |
| static const struct frame_unwind * |
| sparc32obsd_sigtramp_frame_sniffer (struct frame_info *next_frame) |
| { |
| CORE_ADDR pc = frame_pc_unwind (next_frame); |
| char *name; |
| |
| find_pc_partial_function (pc, &name, NULL, NULL); |
| if (sparc32obsd_pc_in_sigtramp (pc, name)) |
| return &sparc32obsd_frame_unwind; |
| |
| return NULL; |
| } |
| |
| |
| /* Offset wthin the thread structure where we can find %fp and %i7. */ |
| #define SPARC32OBSD_UTHREAD_FP_OFFSET 128 |
| #define SPARC32OBSD_UTHREAD_PC_OFFSET 132 |
| |
| static void |
| sparc32obsd_supply_uthread (struct regcache *regcache, |
| int regnum, CORE_ADDR addr) |
| { |
| CORE_ADDR fp, fp_addr = addr + SPARC32OBSD_UTHREAD_FP_OFFSET; |
| gdb_byte buf[4]; |
| |
| gdb_assert (regnum >= -1); |
| |
| fp = read_memory_unsigned_integer (fp_addr, 4); |
| if (regnum == SPARC_SP_REGNUM || regnum == -1) |
| { |
| store_unsigned_integer (buf, 4, fp); |
| regcache_raw_supply (regcache, SPARC_SP_REGNUM, buf); |
| |
| if (regnum == SPARC_SP_REGNUM) |
| return; |
| } |
| |
| if (regnum == SPARC32_PC_REGNUM || regnum == SPARC32_NPC_REGNUM |
| || regnum == -1) |
| { |
| CORE_ADDR i7, i7_addr = addr + SPARC32OBSD_UTHREAD_PC_OFFSET; |
| |
| i7 = read_memory_unsigned_integer (i7_addr, 4); |
| if (regnum == SPARC32_PC_REGNUM || regnum == -1) |
| { |
| store_unsigned_integer (buf, 4, i7 + 8); |
| regcache_raw_supply (regcache, SPARC32_PC_REGNUM, buf); |
| } |
| if (regnum == SPARC32_NPC_REGNUM || regnum == -1) |
| { |
| store_unsigned_integer (buf, 4, i7 + 12); |
| regcache_raw_supply (regcache, SPARC32_NPC_REGNUM, buf); |
| } |
| |
| if (regnum == SPARC32_PC_REGNUM || regnum == SPARC32_NPC_REGNUM) |
| return; |
| } |
| |
| sparc_supply_rwindow (regcache, fp, regnum); |
| } |
| |
| static void |
| sparc32obsd_collect_uthread(const struct regcache *regcache, |
| int regnum, CORE_ADDR addr) |
| { |
| CORE_ADDR sp; |
| gdb_byte buf[4]; |
| |
| gdb_assert (regnum >= -1); |
| |
| if (regnum == SPARC_SP_REGNUM || regnum == -1) |
| { |
| CORE_ADDR fp_addr = addr + SPARC32OBSD_UTHREAD_FP_OFFSET; |
| |
| regcache_raw_collect (regcache, SPARC_SP_REGNUM, buf); |
| write_memory (fp_addr,buf, 4); |
| } |
| |
| if (regnum == SPARC32_PC_REGNUM || regnum == -1) |
| { |
| CORE_ADDR i7, i7_addr = addr + SPARC32OBSD_UTHREAD_PC_OFFSET; |
| |
| regcache_raw_collect (regcache, SPARC32_PC_REGNUM, buf); |
| i7 = extract_unsigned_integer (buf, 4) - 8; |
| write_memory_unsigned_integer (i7_addr, 4, i7); |
| |
| if (regnum == SPARC32_PC_REGNUM) |
| return; |
| } |
| |
| regcache_raw_collect (regcache, SPARC_SP_REGNUM, buf); |
| sp = extract_unsigned_integer (buf, 4); |
| sparc_collect_rwindow (regcache, sp, regnum); |
| } |
| |
| |
| static void |
| sparc32obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| { |
| struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| |
| /* OpenBSD/sparc is very similar to NetBSD/sparc ELF. */ |
| sparc32nbsd_elf_init_abi (info, gdbarch); |
| |
| set_gdbarch_skip_solib_resolver (gdbarch, obsd_skip_solib_resolver); |
| |
| frame_unwind_append_sniffer (gdbarch, sparc32obsd_sigtramp_frame_sniffer); |
| |
| /* OpenBSD provides a user-level threads implementation. */ |
| bsd_uthread_set_supply_uthread (gdbarch, sparc32obsd_supply_uthread); |
| bsd_uthread_set_collect_uthread (gdbarch, sparc32obsd_collect_uthread); |
| } |
| |
| |
| /* Provide a prototype to silence -Wmissing-prototypes. */ |
| void _initialize_sparc32obsd_tdep (void); |
| |
| void |
| _initialize_sparc32obsd_tdep (void) |
| { |
| gdbarch_register_osabi (bfd_arch_sparc, 0, GDB_OSABI_OPENBSD_ELF, |
| sparc32obsd_init_abi); |
| } |