gdb/mips64-obsd-tdep.c

   1 /* Target-dependent code for OpenBSD/mips64.
   2
   3    Copyright (C) 2004-2024 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "gdbtypes.h"
  21 #include "osabi.h"
  22 #include "regcache.h"
  23 #include "regset.h"
  24 #include "trad-frame.h"
  25 #include "tramp-frame.h"
  26
  27 #include "obsd-tdep.h"
  28 #include "mips-tdep.h"
  29 #include "solib-svr4.h"
  30
  31 #define MIPS64OBSD_NUM_REGS 73
  32
  33 /* Core file support.  */
  34
  35 /* Supply register REGNUM from the buffer specified by GREGS and LEN
  36    in the general-purpose register set REGSET to register cache
  37    REGCACHE.  If REGNUM is -1, do this for all registers in REGSET.  */
  38
  39 static void
  40 mips64obsd_supply_gregset (const struct regset *regset,
  41                            struct regcache *regcache, int regnum,
  42                            const void *gregs, size_t len)
  43 {
  44   const char *regs = (const char *) gregs;
  45   int i;
  46
  47   for (i = 0; i < MIPS64OBSD_NUM_REGS; i++)
  48     {
  49       if (regnum == i || regnum == -1)
  50         regcache->raw_supply (i, regs + i * 8);
  51     }
  52 }
  53
  54 /* OpenBSD/mips64 register set.  */
  55
  56 static const struct regset mips64obsd_gregset =
  57 {
  58   NULL,
  59   mips64obsd_supply_gregset
  60 };
  61
  62 /* Iterate over core file register note sections.  */
  63
  64 static void
  65 mips64obsd_iterate_over_regset_sections (struct gdbarch *gdbarch,
  66                                          iterate_over_regset_sections_cb *cb,
  67                                          void *cb_data,
  68                                          const struct regcache *regcache)
  69 {
  70   cb (".reg", MIPS64OBSD_NUM_REGS * 8, MIPS64OBSD_NUM_REGS * 8,
  71       &mips64obsd_gregset, NULL, cb_data);
  72 }
  73 \f
  74
  75 /* Signal trampolines.  */
  76
  77 static void
  78 mips64obsd_sigframe_init (const struct tramp_frame *self,
  79                           const frame_info_ptr &this_frame,
  80                           struct trad_frame_cache *cache,
  81                           CORE_ADDR func)
  82 {
  83   struct gdbarch *gdbarch = get_frame_arch (this_frame);
  84   CORE_ADDR sp, sigcontext_addr, addr;
  85   int regnum;
  86
  87   /* We find the appropriate instance of `struct sigcontext' at a
  88      fixed offset in the signal frame.  */
  89   sp = get_frame_register_signed (this_frame,
  90                                   MIPS_SP_REGNUM + gdbarch_num_regs (gdbarch));
  91   sigcontext_addr = sp + 32;
  92
  93   /* PC.  */
  94   regnum = mips_regnum (gdbarch)->pc;
  95   trad_frame_set_reg_addr (cache,
  96                            regnum + gdbarch_num_regs (gdbarch),
  97                             sigcontext_addr + 16);
  98
  99   /* GPRs.  */
 100   for (regnum = MIPS_AT_REGNUM, addr = sigcontext_addr + 32;
 101        regnum <= MIPS_RA_REGNUM; regnum++, addr += 8)
 102     trad_frame_set_reg_addr (cache,
 103                              regnum + gdbarch_num_regs (gdbarch),
 104                              addr);
 105
 106   /* HI and LO.  */
 107   regnum = mips_regnum (gdbarch)->lo;
 108   trad_frame_set_reg_addr (cache,
 109                            regnum + gdbarch_num_regs (gdbarch),
 110                            sigcontext_addr + 280);
 111   regnum = mips_regnum (gdbarch)->hi;
 112   trad_frame_set_reg_addr (cache,
 113                            regnum + gdbarch_num_regs (gdbarch),
 114                            sigcontext_addr + 288);
 115
 116   /* TODO: Handle the floating-point registers.  */
 117
 118   trad_frame_set_id (cache, frame_id_build (sp, func));
 119 }
 120
 121 static const struct tramp_frame mips64obsd_sigframe =
 122 {
 123   SIGTRAMP_FRAME,
 124   MIPS_INSN32_SIZE,
 125   {
 126     { 0x67a40020, ULONGEST_MAX },               /* daddiu  a0,sp,32 */
 127     { 0x24020067, ULONGEST_MAX },               /* li      v0,103 */
 128     { 0x0000000c, ULONGEST_MAX },               /* syscall */
 129     { 0x0000000d, ULONGEST_MAX },               /* break */
 130     { TRAMP_SENTINEL_INSN, ULONGEST_MAX }
 131   },
 132   mips64obsd_sigframe_init
 133 };
 134
 135 \f
 136 static void
 137 mips64obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 138 {
 139   /* OpenBSD/mips64 only supports the n64 ABI, but the braindamaged
 140      way GDB works, forces us to pretend we can handle them all.  */
 141
 142   set_gdbarch_iterate_over_regset_sections
 143     (gdbarch, mips64obsd_iterate_over_regset_sections);
 144
 145   tramp_frame_prepend_unwinder (gdbarch, &mips64obsd_sigframe);
 146
 147   set_gdbarch_long_double_bit (gdbarch, 128);
 148   set_gdbarch_long_double_format (gdbarch, floatformats_ieee_quad);
 149
 150   obsd_init_abi(info, gdbarch);
 151
 152   /* OpenBSD/mips64 has SVR4-style shared libraries.  */
 153   set_solib_svr4_fetch_link_map_offsets
 154     (gdbarch, svr4_lp64_fetch_link_map_offsets);
 155 }
 156
 157 void _initialize_mips64obsd_tdep ();
 158 void
 159 _initialize_mips64obsd_tdep ()
 160 {
 161   gdbarch_register_osabi (bfd_arch_mips, 0, GDB_OSABI_OPENBSD,
 162                           mips64obsd_init_abi);
 163 }