gdb/ppcnbsd-tdep.c

   1 /* Target-dependent code for PowerPC systems running NetBSD.
   2
   3    Copyright 2002, 2003, 2004 Free Software Foundation, Inc.
   4
   5    Contributed by Wasabi Systems, Inc.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 59 Temple Place - Suite 330,
  22    Boston, MA 02111-1307, USA.  */
  23
  24 #include "defs.h"
  25 #include "gdbcore.h"
  26 #include "regcache.h"
  27 #include "target.h"
  28 #include "breakpoint.h"
  29 #include "value.h"
  30 #include "osabi.h"
  31
  32 #include "ppc-tdep.h"
  33 #include "ppcnbsd-tdep.h"
  34 #include "nbsd-tdep.h"
  35 #include "tramp-frame.h"
  36 #include "trad-frame.h"
  37
  38 #include "solib-svr4.h"
  39
  40 #define REG_FIXREG_OFFSET(x)    ((x) * 4)
  41 #define REG_LR_OFFSET           (32 * 4)
  42 #define REG_CR_OFFSET           (33 * 4)
  43 #define REG_XER_OFFSET          (34 * 4)
  44 #define REG_CTR_OFFSET          (35 * 4)
  45 #define REG_PC_OFFSET           (36 * 4)
  46 #define SIZEOF_STRUCT_REG       (37 * 4)
  47
  48 #define FPREG_FPR_OFFSET(x)     ((x) * 8)
  49 #define FPREG_FPSCR_OFFSET      (32 * 8)
  50 #define SIZEOF_STRUCT_FPREG     (33 * 8)
  51
  52 void
  53 ppcnbsd_supply_reg (char *regs, int regno)
  54 {
  55   struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
  56   int i;
  57
  58   for (i = 0; i <= 31; i++)
  59     {
  60       if (regno == i || regno == -1)
  61         supply_register (i, regs + REG_FIXREG_OFFSET (i));
  62     }
  63
  64   if (regno == tdep->ppc_lr_regnum || regno == -1)
  65     supply_register (tdep->ppc_lr_regnum, regs + REG_LR_OFFSET);
  66
  67   if (regno == tdep->ppc_cr_regnum || regno == -1)
  68     supply_register (tdep->ppc_cr_regnum, regs + REG_CR_OFFSET);
  69
  70   if (regno == tdep->ppc_xer_regnum || regno == -1)
  71     supply_register (tdep->ppc_xer_regnum, regs + REG_XER_OFFSET);
  72
  73   if (regno == tdep->ppc_ctr_regnum || regno == -1)
  74     supply_register (tdep->ppc_ctr_regnum, regs + REG_CTR_OFFSET);
  75
  76   if (regno == PC_REGNUM || regno == -1)
  77     supply_register (PC_REGNUM, regs + REG_PC_OFFSET);
  78 }
  79
  80 void
  81 ppcnbsd_fill_reg (char *regs, int regno)
  82 {
  83   struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
  84   int i;
  85
  86   for (i = 0; i <= 31; i++)
  87     {
  88       if (regno == i || regno == -1)
  89         regcache_collect (i, regs + REG_FIXREG_OFFSET (i));
  90     }
  91
  92   if (regno == tdep->ppc_lr_regnum || regno == -1)
  93     regcache_collect (tdep->ppc_lr_regnum, regs + REG_LR_OFFSET);
  94
  95   if (regno == tdep->ppc_cr_regnum || regno == -1)
  96     regcache_collect (tdep->ppc_cr_regnum, regs + REG_CR_OFFSET);
  97
  98   if (regno == tdep->ppc_xer_regnum || regno == -1)
  99     regcache_collect (tdep->ppc_xer_regnum, regs + REG_XER_OFFSET);
 100
 101   if (regno == tdep->ppc_ctr_regnum || regno == -1)
 102     regcache_collect (tdep->ppc_ctr_regnum, regs + REG_CTR_OFFSET);
 103
 104   if (regno == PC_REGNUM || regno == -1)
 105     regcache_collect (PC_REGNUM, regs + REG_PC_OFFSET);
 106 }
 107
 108 void
 109 ppcnbsd_supply_fpreg (char *fpregs, int regno)
 110 {
 111   struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
 112   int i;
 113
 114   for (i = 0; i < ppc_num_fprs; i++)
 115     {
 116       if (regno == tdep->ppc_fp0_regnum + i || regno == -1)
 117         supply_register (tdep->ppc_fp0_regnum + i,
 118                          fpregs + FPREG_FPR_OFFSET (i));
 119     }
 120
 121   if (regno == tdep->ppc_fpscr_regnum || regno == -1)
 122     supply_register (tdep->ppc_fpscr_regnum, fpregs + FPREG_FPSCR_OFFSET);
 123 }
 124
 125 void
 126 ppcnbsd_fill_fpreg (char *fpregs, int regno)
 127 {
 128   struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
 129   int i;
 130
 131   for (i = 0; i < ppc_num_fprs; i++)
 132     {
 133       if (regno == tdep->ppc_fp0_regnum + i || regno == -1)
 134         regcache_collect (tdep->ppc_fp0_regnum + i,
 135                           fpregs + FPREG_FPR_OFFSET (i));
 136     }
 137
 138   if (regno == tdep->ppc_fpscr_regnum || regno == -1)
 139     regcache_collect (tdep->ppc_fpscr_regnum, fpregs + FPREG_FPSCR_OFFSET);
 140 }
 141
 142 static void
 143 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size, int which,
 144                       CORE_ADDR ignore)
 145 {
 146   char *regs, *fpregs;
 147
 148   /* We get everything from one section.  */
 149   if (which != 0)
 150     return;
 151
 152   regs = core_reg_sect;
 153   fpregs = core_reg_sect + SIZEOF_STRUCT_REG;
 154
 155   /* Integer registers.  */
 156   ppcnbsd_supply_reg (regs, -1);
 157
 158   /* Floating point registers.  */
 159   ppcnbsd_supply_fpreg (fpregs, -1);
 160 }
 161
 162 static void
 163 fetch_elfcore_registers (char *core_reg_sect, unsigned core_reg_size, int which,
 164                          CORE_ADDR ignore)
 165 {
 166   switch (which)
 167     {
 168     case 0:  /* Integer registers.  */
 169       if (core_reg_size != SIZEOF_STRUCT_REG)
 170         warning ("Wrong size register set in core file.");
 171       else
 172         ppcnbsd_supply_reg (core_reg_sect, -1);
 173       break;
 174
 175     case 2:  /* Floating point registers.  */
 176       if (core_reg_size != SIZEOF_STRUCT_FPREG)
 177         warning ("Wrong size FP register set in core file.");
 178       else
 179         ppcnbsd_supply_fpreg (core_reg_sect, -1);
 180       break;
 181
 182     default:
 183       /* Don't know what kind of register request this is; just ignore it.  */
 184       break;
 185     }
 186 }
 187
 188 static struct core_fns ppcnbsd_core_fns =
 189 {
 190   bfd_target_unknown_flavour,           /* core_flavour */
 191   default_check_format,                 /* check_format */
 192   default_core_sniffer,                 /* core_sniffer */
 193   fetch_core_registers,                 /* core_read_registers */
 194   NULL                                  /* next */
 195 };
 196
 197 static struct core_fns ppcnbsd_elfcore_fns =
 198 {
 199   bfd_target_elf_flavour,               /* core_flavour */
 200   default_check_format,                 /* check_format */
 201   default_core_sniffer,                 /* core_sniffer */
 202   fetch_elfcore_registers,              /* core_read_registers */
 203   NULL                                  /* next */
 204 };
 205
 206 /* NetBSD is confused.  It appears that 1.5 was using the correct SVr4
 207    convention but, 1.6 switched to the below broken convention.  For
 208    the moment use the broken convention.  Ulgh!.  */
 209
 210 static enum return_value_convention
 211 ppcnbsd_return_value (struct gdbarch *gdbarch, struct type *valtype,
 212                       struct regcache *regcache, void *readbuf,
 213                       const void *writebuf)
 214 {
 215   if ((TYPE_CODE (valtype) == TYPE_CODE_STRUCT
 216        || TYPE_CODE (valtype) == TYPE_CODE_UNION)
 217       && !((TYPE_LENGTH (valtype) == 16 || TYPE_LENGTH (valtype) == 8)
 218             && TYPE_VECTOR (valtype))
 219       && !(TYPE_LENGTH (valtype) == 1
 220            || TYPE_LENGTH (valtype) == 2
 221            || TYPE_LENGTH (valtype) == 4
 222            || TYPE_LENGTH (valtype) == 8))
 223     return RETURN_VALUE_STRUCT_CONVENTION;
 224   else
 225     return ppc_sysv_abi_broken_return_value (gdbarch, valtype, regcache,
 226                                              readbuf, writebuf);
 227 }
 228
 229 static void
 230 ppcnbsd_sigtramp_cache_init (const struct tramp_frame *self,
 231                              struct frame_info *next_frame,
 232                              struct trad_frame_cache *this_cache,
 233                              CORE_ADDR func)
 234 {
 235   CORE_ADDR base;
 236   CORE_ADDR offset;
 237   int i;
 238   struct gdbarch *gdbarch = get_frame_arch (next_frame);
 239   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 240
 241   base = frame_unwind_register_unsigned (next_frame, SP_REGNUM);
 242   offset = base + 0x18 + 2 * tdep->wordsize;
 243   for (i = 0; i < 32; i++)
 244     {
 245       int regnum = i + tdep->ppc_gp0_regnum;
 246       trad_frame_set_reg_addr (this_cache, regnum, offset);
 247       offset += tdep->wordsize;
 248     }
 249   trad_frame_set_reg_addr (this_cache, tdep->ppc_lr_regnum, offset);
 250   offset += tdep->wordsize;
 251   trad_frame_set_reg_addr (this_cache, tdep->ppc_cr_regnum, offset);
 252   offset += tdep->wordsize;
 253   trad_frame_set_reg_addr (this_cache, tdep->ppc_xer_regnum, offset);
 254   offset += tdep->wordsize;
 255   trad_frame_set_reg_addr (this_cache, tdep->ppc_ctr_regnum, offset);
 256   offset += tdep->wordsize;
 257   trad_frame_set_reg_addr (this_cache, PC_REGNUM, offset); /* SRR0? */
 258   offset += tdep->wordsize;
 259
 260   /* Construct the frame ID using the function start.  */
 261   trad_frame_set_id (this_cache, frame_id_build (base, func));
 262 }
 263
 264 /* Given the NEXT frame, examine the instructions at and around this
 265    frame's resume address (aka PC) to see of they look like a signal
 266    trampoline.  Return the address of the trampolines first
 267    instruction, or zero if it isn't a signal trampoline.  */
 268
 269 static const struct tramp_frame ppcnbsd_sigtramp = {
 270   4, /* insn size */
 271   { /* insn */
 272     0x38610018, /* addi r3,r1,24 */
 273     0x38000127, /* li r0,295 */
 274     0x44000002, /* sc */
 275     0x38000001, /* li r0,1 */
 276     0x44000002, /* sc */
 277     TRAMP_SENTINEL_INSN
 278   },
 279   ppcnbsd_sigtramp_cache_init
 280 };
 281
 282 static void
 283 ppcnbsd_init_abi (struct gdbarch_info info,
 284                   struct gdbarch *gdbarch)
 285 {
 286   /* For NetBSD, this is an on again, off again thing.  Some systems
 287      do use the broken struct convention, and some don't.  */
 288   set_gdbarch_return_value (gdbarch, ppcnbsd_return_value);
 289   set_solib_svr4_fetch_link_map_offsets (gdbarch,
 290                                 nbsd_ilp32_solib_svr4_fetch_link_map_offsets);
 291   tramp_frame_prepend_unwinder (gdbarch, &ppcnbsd_sigtramp);
 292 }
 293
 294 void
 295 _initialize_ppcnbsd_tdep (void)
 296 {
 297   gdbarch_register_osabi (bfd_arch_powerpc, 0, GDB_OSABI_NETBSD_ELF,
 298                           ppcnbsd_init_abi);
 299
 300   deprecated_add_core_fns (&ppcnbsd_core_fns);
 301   deprecated_add_core_fns (&ppcnbsd_elfcore_fns);
 302 }