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 = FP0_REGNUM; i <= FP0_REGNUM + 31; i++)
 115     {
 116       if (regno == i || regno == -1)
 117         supply_register (i, fpregs + FPREG_FPR_OFFSET (i - FP0_REGNUM));
 118     }
 119
 120   if (regno == tdep->ppc_fpscr_regnum || regno == -1)
 121     supply_register (tdep->ppc_fpscr_regnum, fpregs + FPREG_FPSCR_OFFSET);
 122 }
 123
 124 void
 125 ppcnbsd_fill_fpreg (char *fpregs, int regno)
 126 {
 127   struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
 128   int i;
 129
 130   for (i = FP0_REGNUM; i <= FP0_REGNUM + 31; i++)
 131     {
 132       if (regno == i || regno == -1)
 133         regcache_collect (i, fpregs + FPREG_FPR_OFFSET (i - FP0_REGNUM));
 134     }
 135
 136   if (regno == tdep->ppc_fpscr_regnum || regno == -1)
 137     regcache_collect (tdep->ppc_fpscr_regnum, fpregs + FPREG_FPSCR_OFFSET);
 138 }
 139
 140 static void
 141 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size, int which,
 142                       CORE_ADDR ignore)
 143 {
 144   char *regs, *fpregs;
 145
 146   /* We get everything from one section.  */
 147   if (which != 0)
 148     return;
 149
 150   regs = core_reg_sect;
 151   fpregs = core_reg_sect + SIZEOF_STRUCT_REG;
 152
 153   /* Integer registers.  */
 154   ppcnbsd_supply_reg (regs, -1);
 155
 156   /* Floating point registers.  */
 157   ppcnbsd_supply_fpreg (fpregs, -1);
 158 }
 159
 160 static void
 161 fetch_elfcore_registers (char *core_reg_sect, unsigned core_reg_size, int which,
 162                          CORE_ADDR ignore)
 163 {
 164   switch (which)
 165     {
 166     case 0:  /* Integer registers.  */
 167       if (core_reg_size != SIZEOF_STRUCT_REG)
 168         warning ("Wrong size register set in core file.");
 169       else
 170         ppcnbsd_supply_reg (core_reg_sect, -1);
 171       break;
 172
 173     case 2:  /* Floating point registers.  */
 174       if (core_reg_size != SIZEOF_STRUCT_FPREG)
 175         warning ("Wrong size FP register set in core file.");
 176       else
 177         ppcnbsd_supply_fpreg (core_reg_sect, -1);
 178       break;
 179
 180     default:
 181       /* Don't know what kind of register request this is; just ignore it.  */
 182       break;
 183     }
 184 }
 185
 186 static struct core_fns ppcnbsd_core_fns =
 187 {
 188   bfd_target_unknown_flavour,           /* core_flavour */
 189   default_check_format,                 /* check_format */
 190   default_core_sniffer,                 /* core_sniffer */
 191   fetch_core_registers,                 /* core_read_registers */
 192   NULL                                  /* next */
 193 };
 194
 195 static struct core_fns ppcnbsd_elfcore_fns =
 196 {
 197   bfd_target_elf_flavour,               /* core_flavour */
 198   default_check_format,                 /* check_format */
 199   default_core_sniffer,                 /* core_sniffer */
 200   fetch_elfcore_registers,              /* core_read_registers */
 201   NULL                                  /* next */
 202 };
 203
 204 /* NetBSD is confused.  It appears that 1.5 was using the correct SVr4
 205    convention but, 1.6 switched to the below broken convention.  For
 206    the moment use the broken convention.  Ulgh!.  */
 207
 208 static enum return_value_convention
 209 ppcnbsd_return_value (struct gdbarch *gdbarch, struct type *valtype,
 210                       struct regcache *regcache, void *readbuf,
 211                       const void *writebuf)
 212 {
 213   if ((TYPE_CODE (valtype) == TYPE_CODE_STRUCT
 214        || TYPE_CODE (valtype) == TYPE_CODE_UNION)
 215       && !((TYPE_LENGTH (valtype) == 16 || TYPE_LENGTH (valtype) == 8)
 216             && TYPE_VECTOR (valtype))
 217       && !(TYPE_LENGTH (valtype) == 1
 218            || TYPE_LENGTH (valtype) == 2
 219            || TYPE_LENGTH (valtype) == 4
 220            || TYPE_LENGTH (valtype) == 8))
 221     return RETURN_VALUE_STRUCT_CONVENTION;
 222   else
 223     return ppc_sysv_abi_broken_return_value (gdbarch, valtype, regcache,
 224                                              readbuf, writebuf);
 225 }
 226
 227 static void
 228 ppcnbsd_sigtramp_cache_init (const struct tramp_frame *self,
 229                              struct frame_info *next_frame,
 230                              struct trad_frame_cache *this_cache,
 231                              CORE_ADDR func)
 232 {
 233   CORE_ADDR base;
 234   CORE_ADDR offset;
 235   int i;
 236   struct gdbarch *gdbarch = get_frame_arch (next_frame);
 237   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 238
 239   base = frame_unwind_register_unsigned (next_frame, SP_REGNUM);
 240   offset = base + 0x18 + 2 * tdep->wordsize;
 241   for (i = 0; i < 32; i++)
 242     {
 243       int regnum = i + tdep->ppc_gp0_regnum;
 244       trad_frame_set_reg_addr (this_cache, regnum, offset);
 245       offset += tdep->wordsize;
 246     }
 247   trad_frame_set_reg_addr (this_cache, tdep->ppc_lr_regnum, offset);
 248   offset += tdep->wordsize;
 249   trad_frame_set_reg_addr (this_cache, tdep->ppc_cr_regnum, offset);
 250   offset += tdep->wordsize;
 251   trad_frame_set_reg_addr (this_cache, tdep->ppc_xer_regnum, offset);
 252   offset += tdep->wordsize;
 253   trad_frame_set_reg_addr (this_cache, tdep->ppc_ctr_regnum, offset);
 254   offset += tdep->wordsize;
 255   trad_frame_set_reg_addr (this_cache, PC_REGNUM, offset); /* SRR0? */
 256   offset += tdep->wordsize;
 257
 258   /* Construct the frame ID using the function start.  */
 259   trad_frame_set_id (this_cache, frame_id_build (base, func));
 260 }
 261
 262 /* Given the NEXT frame, examine the instructions at and around this
 263    frame's resume address (aka PC) to see of they look like a signal
 264    trampoline.  Return the address of the trampolines first
 265    instruction, or zero if it isn't a signal trampoline.  */
 266
 267 static const struct tramp_frame ppcnbsd_sigtramp = {
 268   4, /* insn size */
 269   { /* insn */
 270     0x38610018, /* addi r3,r1,24 */
 271     0x38000127, /* li r0,295 */
 272     0x44000002, /* sc */
 273     0x38000001, /* li r0,1 */
 274     0x44000002, /* sc */
 275     TRAMP_SENTINEL_INSN
 276   },
 277   ppcnbsd_sigtramp_cache_init
 278 };
 279
 280 static void
 281 ppcnbsd_init_abi (struct gdbarch_info info,
 282                   struct gdbarch *gdbarch)
 283 {
 284   /* For NetBSD, this is an on again, off again thing.  Some systems
 285      do use the broken struct convention, and some don't.  */
 286   set_gdbarch_return_value (gdbarch, ppcnbsd_return_value);
 287   set_solib_svr4_fetch_link_map_offsets (gdbarch,
 288                                 nbsd_ilp32_solib_svr4_fetch_link_map_offsets);
 289   tramp_frame_prepend_unwinder (gdbarch, &ppcnbsd_sigtramp);
 290 }
 291
 292 void
 293 _initialize_ppcnbsd_tdep (void)
 294 {
 295   gdbarch_register_osabi (bfd_arch_powerpc, 0, GDB_OSABI_NETBSD_ELF,
 296                           ppcnbsd_init_abi);
 297
 298   deprecated_add_core_fns (&ppcnbsd_core_fns);
 299   deprecated_add_core_fns (&ppcnbsd_elfcore_fns);
 300 }