gdb/ns32knbsd-nat.c

   1 /* Functions specific to running gdb native on an ns32k running NetBSD
   2    Copyright 1989, 1992, 1993, 1994, 1996, 1998, 1999, 2000, 2001
   3    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 2 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, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include <sys/types.h>
  23 #include <sys/ptrace.h>
  24 #include <machine/reg.h>
  25 #include <machine/frame.h>
  26 #include <machine/pcb.h>
  27
  28 #include "defs.h"
  29 #include "inferior.h"
  30 #include "target.h"
  31 #include "gdbcore.h"
  32 #include "regcache.h"
  33
  34 #define RF(dst, src) \
  35         memcpy(&registers[REGISTER_BYTE(dst)], &src, sizeof(src))
  36
  37 #define RS(src, dst) \
  38         memcpy(&dst, &registers[REGISTER_BYTE(src)], sizeof(dst))
  39
  40 void
  41 fetch_inferior_registers (int regno)
  42 {
  43   struct reg inferior_registers;
  44   struct fpreg inferior_fpregisters;
  45
  46   ptrace (PT_GETREGS, PIDGET (inferior_ptid),
  47           (PTRACE_ARG3_TYPE) & inferior_registers, 0);
  48   ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
  49           (PTRACE_ARG3_TYPE) & inferior_fpregisters, 0);
  50
  51   RF (R0_REGNUM + 0, inferior_registers.r_r0);
  52   RF (R0_REGNUM + 1, inferior_registers.r_r1);
  53   RF (R0_REGNUM + 2, inferior_registers.r_r2);
  54   RF (R0_REGNUM + 3, inferior_registers.r_r3);
  55   RF (R0_REGNUM + 4, inferior_registers.r_r4);
  56   RF (R0_REGNUM + 5, inferior_registers.r_r5);
  57   RF (R0_REGNUM + 6, inferior_registers.r_r6);
  58   RF (R0_REGNUM + 7, inferior_registers.r_r7);
  59
  60   RF (SP_REGNUM, inferior_registers.r_sp);
  61   RF (FP_REGNUM, inferior_registers.r_fp);
  62   RF (PC_REGNUM, inferior_registers.r_pc);
  63   RF (PS_REGNUM, inferior_registers.r_psr);
  64
  65   RF (FPS_REGNUM, inferior_fpregisters.r_fsr);
  66   RF (FP0_REGNUM + 0, inferior_fpregisters.r_freg[0]);
  67   RF (FP0_REGNUM + 2, inferior_fpregisters.r_freg[2]);
  68   RF (FP0_REGNUM + 4, inferior_fpregisters.r_freg[4]);
  69   RF (FP0_REGNUM + 6, inferior_fpregisters.r_freg[6]);
  70   RF (LP0_REGNUM + 1, inferior_fpregisters.r_freg[1]);
  71   RF (LP0_REGNUM + 3, inferior_fpregisters.r_freg[3]);
  72   RF (LP0_REGNUM + 5, inferior_fpregisters.r_freg[5]);
  73   RF (LP0_REGNUM + 7, inferior_fpregisters.r_freg[7]);
  74   registers_fetched ();
  75 }
  76
  77 void
  78 store_inferior_registers (int regno)
  79 {
  80   struct reg inferior_registers;
  81   struct fpreg inferior_fpregisters;
  82
  83   RS (R0_REGNUM + 0, inferior_registers.r_r0);
  84   RS (R0_REGNUM + 1, inferior_registers.r_r1);
  85   RS (R0_REGNUM + 2, inferior_registers.r_r2);
  86   RS (R0_REGNUM + 3, inferior_registers.r_r3);
  87   RS (R0_REGNUM + 4, inferior_registers.r_r4);
  88   RS (R0_REGNUM + 5, inferior_registers.r_r5);
  89   RS (R0_REGNUM + 6, inferior_registers.r_r6);
  90   RS (R0_REGNUM + 7, inferior_registers.r_r7);
  91
  92   RS (SP_REGNUM, inferior_registers.r_sp);
  93   RS (FP_REGNUM, inferior_registers.r_fp);
  94   RS (PC_REGNUM, inferior_registers.r_pc);
  95   RS (PS_REGNUM, inferior_registers.r_psr);
  96
  97   RS (FPS_REGNUM, inferior_fpregisters.r_fsr);
  98   RS (FP0_REGNUM + 0, inferior_fpregisters.r_freg[0]);
  99   RS (FP0_REGNUM + 2, inferior_fpregisters.r_freg[2]);
 100   RS (FP0_REGNUM + 4, inferior_fpregisters.r_freg[4]);
 101   RS (FP0_REGNUM + 6, inferior_fpregisters.r_freg[6]);
 102   RS (LP0_REGNUM + 1, inferior_fpregisters.r_freg[1]);
 103   RS (LP0_REGNUM + 3, inferior_fpregisters.r_freg[3]);
 104   RS (LP0_REGNUM + 5, inferior_fpregisters.r_freg[5]);
 105   RS (LP0_REGNUM + 7, inferior_fpregisters.r_freg[7]);
 106
 107   ptrace (PT_SETREGS, PIDGET (inferior_ptid),
 108           (PTRACE_ARG3_TYPE) & inferior_registers, 0);
 109   ptrace (PT_SETFPREGS, PIDGET (inferior_ptid),
 110           (PTRACE_ARG3_TYPE) & inferior_fpregisters, 0);
 111 }
 112 \f
 113
 114 /* XXX - Add this to machine/regs.h instead? */
 115 struct coreregs
 116 {
 117   struct reg intreg;
 118   struct fpreg freg;
 119 };
 120
 121 /* Get registers from a core file.  REG_ADDR is unused.  */
 122 static void
 123 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size, int which,
 124                       unsigned int reg_addr)
 125 {
 126   struct coreregs *core_reg;
 127
 128   core_reg = (struct coreregs *) core_reg_sect;
 129
 130   /*
 131    * We have *all* registers
 132    * in the first core section.
 133    * Ignore which.
 134    */
 135
 136   if (core_reg_size < sizeof (*core_reg))
 137     {
 138       fprintf_unfiltered (gdb_stderr, "Couldn't read regs from core file\n");
 139       return;
 140     }
 141
 142   /* Integer registers */
 143   RF (R0_REGNUM + 0, core_reg->intreg.r_r0);
 144   RF (R0_REGNUM + 1, core_reg->intreg.r_r1);
 145   RF (R0_REGNUM + 2, core_reg->intreg.r_r2);
 146   RF (R0_REGNUM + 3, core_reg->intreg.r_r3);
 147   RF (R0_REGNUM + 4, core_reg->intreg.r_r4);
 148   RF (R0_REGNUM + 5, core_reg->intreg.r_r5);
 149   RF (R0_REGNUM + 6, core_reg->intreg.r_r6);
 150   RF (R0_REGNUM + 7, core_reg->intreg.r_r7);
 151
 152   RF (SP_REGNUM, core_reg->intreg.r_sp);
 153   RF (FP_REGNUM, core_reg->intreg.r_fp);
 154   RF (PC_REGNUM, core_reg->intreg.r_pc);
 155   RF (PS_REGNUM, core_reg->intreg.r_psr);
 156
 157   /* Floating point registers */
 158   RF (FPS_REGNUM, core_reg->freg.r_fsr);
 159   RF (FP0_REGNUM + 0, core_reg->freg.r_freg[0]);
 160   RF (FP0_REGNUM + 2, core_reg->freg.r_freg[2]);
 161   RF (FP0_REGNUM + 4, core_reg->freg.r_freg[4]);
 162   RF (FP0_REGNUM + 6, core_reg->freg.r_freg[6]);
 163   RF (LP0_REGNUM + 1, core_reg->freg.r_freg[1]);
 164   RF (LP0_REGNUM + 3, core_reg->freg.r_freg[3]);
 165   RF (LP0_REGNUM + 5, core_reg->freg.r_freg[5]);
 166   RF (LP0_REGNUM + 7, core_reg->freg.r_freg[7]);
 167   registers_fetched ();
 168 }
 169
 170 /* Register that we are able to handle ns32knbsd core file formats.
 171    FIXME: is this really bfd_target_unknown_flavour? */
 172
 173 static struct core_fns nat_core_fns =
 174 {
 175   bfd_target_unknown_flavour,           /* core_flavour */
 176   default_check_format,                 /* check_format */
 177   default_core_sniffer,                 /* core_sniffer */
 178   fetch_core_registers,                 /* core_read_registers */
 179   NULL                                  /* next */
 180 };
 181
 182 void
 183 _initialize_ns32knbsd_nat (void)
 184 {
 185   add_core_fns (&nat_core_fns);
 186 }
 187 \f
 188
 189 /*
 190  * kernel_u_size() is not helpful on NetBSD because
 191  * the "u" struct is NOT in the core dump file.
 192  */
 193
 194 #ifdef  FETCH_KCORE_REGISTERS
 195 /*
 196  * Get registers from a kernel crash dump or live kernel.
 197  * Called by kcore-nbsd.c:get_kcore_registers().
 198  */
 199 void
 200 fetch_kcore_registers (struct pcb *pcb)
 201 {
 202   struct switchframe sf;
 203   struct reg intreg;
 204   int dummy;
 205
 206   /* Integer registers */
 207   if (target_read_memory ((CORE_ADDR) pcb->pcb_ksp, (char *) &sf, sizeof sf))
 208     error ("Cannot read integer registers.");
 209
 210   /* We use the psr at kernel entry */
 211   if (target_read_memory ((CORE_ADDR) pcb->pcb_onstack, (char *) &intreg, sizeof intreg))
 212     error ("Cannot read processor status register.");
 213
 214   dummy = 0;
 215   RF (R0_REGNUM + 0, dummy);
 216   RF (R0_REGNUM + 1, dummy);
 217   RF (R0_REGNUM + 2, dummy);
 218   RF (R0_REGNUM + 3, sf.sf_r3);
 219   RF (R0_REGNUM + 4, sf.sf_r4);
 220   RF (R0_REGNUM + 5, sf.sf_r5);
 221   RF (R0_REGNUM + 6, sf.sf_r6);
 222   RF (R0_REGNUM + 7, sf.sf_r7);
 223
 224   dummy = pcb->pcb_kfp + 8;
 225   RF (SP_REGNUM, dummy);
 226   RF (FP_REGNUM, sf.sf_fp);
 227   RF (PC_REGNUM, sf.sf_pc);
 228   RF (PS_REGNUM, intreg.r_psr);
 229
 230   /* Floating point registers */
 231   RF (FPS_REGNUM, pcb->pcb_fsr);
 232   RF (FP0_REGNUM + 0, pcb->pcb_freg[0]);
 233   RF (FP0_REGNUM + 2, pcb->pcb_freg[2]);
 234   RF (FP0_REGNUM + 4, pcb->pcb_freg[4]);
 235   RF (FP0_REGNUM + 6, pcb->pcb_freg[6]);
 236   RF (LP0_REGNUM + 1, pcb->pcb_freg[1]);
 237   RF (LP0_REGNUM + 3, pcb->pcb_freg[3]);
 238   RF (LP0_REGNUM + 5, pcb->pcb_freg[5]);
 239   RF (LP0_REGNUM + 7, pcb->pcb_freg[7]);
 240   registers_fetched ();
 241 }
 242 #endif /* FETCH_KCORE_REGISTERS */
 243
 244 void
 245 clear_regs (void)
 246 {
 247   double zero = 0.0;
 248   int null = 0;
 249
 250   /* Integer registers */
 251   RF (R0_REGNUM + 0, null);
 252   RF (R0_REGNUM + 1, null);
 253   RF (R0_REGNUM + 2, null);
 254   RF (R0_REGNUM + 3, null);
 255   RF (R0_REGNUM + 4, null);
 256   RF (R0_REGNUM + 5, null);
 257   RF (R0_REGNUM + 6, null);
 258   RF (R0_REGNUM + 7, null);
 259
 260   RF (SP_REGNUM, null);
 261   RF (FP_REGNUM, null);
 262   RF (PC_REGNUM, null);
 263   RF (PS_REGNUM, null);
 264
 265   /* Floating point registers */
 266   RF (FPS_REGNUM, zero);
 267   RF (FP0_REGNUM + 0, zero);
 268   RF (FP0_REGNUM + 2, zero);
 269   RF (FP0_REGNUM + 4, zero);
 270   RF (FP0_REGNUM + 6, zero);
 271   RF (LP0_REGNUM + 0, zero);
 272   RF (LP0_REGNUM + 1, zero);
 273   RF (LP0_REGNUM + 2, zero);
 274   RF (LP0_REGNUM + 3, zero);
 275   return;
 276 }
 277
 278 /* Return number of args passed to a frame.
 279    Can return -1, meaning no way to tell. */
 280
 281 int
 282 frame_num_args (struct frame_info *fi)
 283 {
 284   CORE_ADDR enter_addr;
 285   CORE_ADDR argp;
 286   int inst;
 287   int args;
 288   int i;
 289
 290   if (read_memory_integer (fi->frame, 4) == 0 && fi->pc < 0x10000)
 291     {
 292       /* main is always called with three args */
 293       return (3);
 294     }
 295   enter_addr = ns32k_get_enter_addr (fi->pc);
 296   if (enter_addr = 0)
 297     return (-1);
 298   argp = enter_addr == 1 ? SAVED_PC_AFTER_CALL (fi) : FRAME_SAVED_PC (fi);
 299   for (i = 0; i < 16; i++)
 300     {
 301       /*
 302        * After a bsr gcc may emit the following instructions
 303        * to remove the arguments from the stack:
 304        *   cmpqd 0,tos        - to remove 4 bytes from the stack
 305        *   cmpd tos,tos       - to remove 8 bytes from the stack
 306        *   adjsp[bwd] -n      - to remove n bytes from the stack
 307        * Gcc sometimes delays emitting these instructions and
 308        * may even throw a branch between our feet.
 309        */
 310       inst = read_memory_integer (argp, 4);
 311       args = read_memory_integer (argp + 2, 4);
 312       if ((inst & 0xff) == 0xea)
 313         {                       /* br */
 314           args = ((inst >> 8) & 0xffffff) | (args << 24);
 315           if (args & 0x80)
 316             {
 317               if (args & 0x40)
 318                 {
 319                   args = ntohl (args);
 320                 }
 321               else
 322                 {
 323                   args = ntohs (args & 0xffff);
 324                   if (args & 0x2000)
 325                     args |= 0xc000;
 326                 }
 327             }
 328           else
 329             {
 330               args = args & 0xff;
 331               if (args & 0x40)
 332                 args |= 0x80;
 333             }
 334           argp += args;
 335           continue;
 336         }
 337       if ((inst & 0xffff) == 0xb81f)    /* cmpqd 0,tos */
 338         return (1);
 339       else if ((inst & 0xffff) == 0xbdc7)       /* cmpd tos,tos */
 340         return (2);
 341       else if ((inst & 0xfffc) == 0xa57c)
 342         {                       /* adjsp[bwd] */
 343           switch (inst & 3)
 344             {
 345             case 0:
 346               args = ((args & 0xff) + 0x80);
 347               break;
 348             case 1:
 349               args = ((ntohs (args) & 0xffff) + 0x8000);
 350               break;
 351             case 3:
 352               args = -ntohl (args);
 353               break;
 354             default:
 355               return (-1);
 356             }
 357           if (args / 4 > 10 || (args & 3) != 0)
 358             continue;
 359           return (args / 4);
 360         }
 361       argp += 1;
 362     }
 363   return (-1);
 364 }