gdb/ns32knbsd-nat.c

   1 /* Functions specific to running gdb native on an ns32k running NetBSD
   2    Copyright 1989, 1992, 1993, 1994, 1996 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include <sys/types.h>
  22 #include <sys/ptrace.h>
  23 #include <machine/reg.h>
  24 #include <machine/frame.h>
  25 #include <machine/pcb.h>
  26
  27 #include "defs.h"
  28 #include "inferior.h"
  29 #include "target.h"
  30 #include "gdbcore.h"
  31
  32 #define RF(dst, src) \
  33         memcpy(&registers[REGISTER_BYTE(dst)], &src, sizeof(src))
  34
  35 #define RS(src, dst) \
  36         memcpy(&dst, &registers[REGISTER_BYTE(src)], sizeof(dst))
  37
  38 void
  39 fetch_inferior_registers (int regno)
  40 {
  41   struct reg inferior_registers;
  42   struct fpreg inferior_fpregisters;
  43
  44   ptrace (PT_GETREGS, inferior_pid,
  45           (PTRACE_ARG3_TYPE) & inferior_registers, 0);
  46   ptrace (PT_GETFPREGS, inferior_pid,
  47           (PTRACE_ARG3_TYPE) & inferior_fpregisters, 0);
  48
  49   RF (R0_REGNUM + 0, inferior_registers.r_r0);
  50   RF (R0_REGNUM + 1, inferior_registers.r_r1);
  51   RF (R0_REGNUM + 2, inferior_registers.r_r2);
  52   RF (R0_REGNUM + 3, inferior_registers.r_r3);
  53   RF (R0_REGNUM + 4, inferior_registers.r_r4);
  54   RF (R0_REGNUM + 5, inferior_registers.r_r5);
  55   RF (R0_REGNUM + 6, inferior_registers.r_r6);
  56   RF (R0_REGNUM + 7, inferior_registers.r_r7);
  57
  58   RF (SP_REGNUM, inferior_registers.r_sp);
  59   RF (FP_REGNUM, inferior_registers.r_fp);
  60   RF (PC_REGNUM, inferior_registers.r_pc);
  61   RF (PS_REGNUM, inferior_registers.r_psr);
  62
  63   RF (FPS_REGNUM, inferior_fpregisters.r_fsr);
  64   RF (FP0_REGNUM + 0, inferior_fpregisters.r_freg[0]);
  65   RF (FP0_REGNUM + 2, inferior_fpregisters.r_freg[2]);
  66   RF (FP0_REGNUM + 4, inferior_fpregisters.r_freg[4]);
  67   RF (FP0_REGNUM + 6, inferior_fpregisters.r_freg[6]);
  68   RF (LP0_REGNUM + 1, inferior_fpregisters.r_freg[1]);
  69   RF (LP0_REGNUM + 3, inferior_fpregisters.r_freg[3]);
  70   RF (LP0_REGNUM + 5, inferior_fpregisters.r_freg[5]);
  71   RF (LP0_REGNUM + 7, inferior_fpregisters.r_freg[7]);
  72   registers_fetched ();
  73 }
  74
  75 void
  76 store_inferior_registers (int regno)
  77 {
  78   struct reg inferior_registers;
  79   struct fpreg inferior_fpregisters;
  80
  81   RS (R0_REGNUM + 0, inferior_registers.r_r0);
  82   RS (R0_REGNUM + 1, inferior_registers.r_r1);
  83   RS (R0_REGNUM + 2, inferior_registers.r_r2);
  84   RS (R0_REGNUM + 3, inferior_registers.r_r3);
  85   RS (R0_REGNUM + 4, inferior_registers.r_r4);
  86   RS (R0_REGNUM + 5, inferior_registers.r_r5);
  87   RS (R0_REGNUM + 6, inferior_registers.r_r6);
  88   RS (R0_REGNUM + 7, inferior_registers.r_r7);
  89
  90   RS (SP_REGNUM, inferior_registers.r_sp);
  91   RS (FP_REGNUM, inferior_registers.r_fp);
  92   RS (PC_REGNUM, inferior_registers.r_pc);
  93   RS (PS_REGNUM, inferior_registers.r_psr);
  94
  95   RS (FPS_REGNUM, inferior_fpregisters.r_fsr);
  96   RS (FP0_REGNUM + 0, inferior_fpregisters.r_freg[0]);
  97   RS (FP0_REGNUM + 2, inferior_fpregisters.r_freg[2]);
  98   RS (FP0_REGNUM + 4, inferior_fpregisters.r_freg[4]);
  99   RS (FP0_REGNUM + 6, inferior_fpregisters.r_freg[6]);
 100   RS (LP0_REGNUM + 1, inferior_fpregisters.r_freg[1]);
 101   RS (LP0_REGNUM + 3, inferior_fpregisters.r_freg[3]);
 102   RS (LP0_REGNUM + 5, inferior_fpregisters.r_freg[5]);
 103   RS (LP0_REGNUM + 7, inferior_fpregisters.r_freg[7]);
 104
 105   ptrace (PT_SETREGS, inferior_pid,
 106           (PTRACE_ARG3_TYPE) & inferior_registers, 0);
 107   ptrace (PT_SETFPREGS, inferior_pid,
 108           (PTRACE_ARG3_TYPE) & inferior_fpregisters, 0);
 109 }
 110 \f
 111
 112 /* XXX - Add this to machine/regs.h instead? */
 113 struct coreregs
 114 {
 115   struct reg intreg;
 116   struct fpreg freg;
 117 };
 118
 119 /* Get registers from a core file. */
 120 static void
 121 fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
 122      char *core_reg_sect;
 123      unsigned core_reg_size;
 124      int which;
 125      unsigned int reg_addr;     /* Unused in this version */
 126 {
 127   struct coreregs *core_reg;
 128
 129   core_reg = (struct coreregs *) core_reg_sect;
 130
 131   /*
 132    * We have *all* registers
 133    * in the first core section.
 134    * Ignore which.
 135    */
 136
 137   if (core_reg_size < sizeof (*core_reg))
 138     {
 139       fprintf_unfiltered (gdb_stderr, "Couldn't read regs from core file\n");
 140       return;
 141     }
 142
 143   /* Integer registers */
 144   RF (R0_REGNUM + 0, core_reg->intreg.r_r0);
 145   RF (R0_REGNUM + 1, core_reg->intreg.r_r1);
 146   RF (R0_REGNUM + 2, core_reg->intreg.r_r2);
 147   RF (R0_REGNUM + 3, core_reg->intreg.r_r3);
 148   RF (R0_REGNUM + 4, core_reg->intreg.r_r4);
 149   RF (R0_REGNUM + 5, core_reg->intreg.r_r5);
 150   RF (R0_REGNUM + 6, core_reg->intreg.r_r6);
 151   RF (R0_REGNUM + 7, core_reg->intreg.r_r7);
 152
 153   RF (SP_REGNUM, core_reg->intreg.r_sp);
 154   RF (FP_REGNUM, core_reg->intreg.r_fp);
 155   RF (PC_REGNUM, core_reg->intreg.r_pc);
 156   RF (PS_REGNUM, core_reg->intreg.r_psr);
 157
 158   /* Floating point registers */
 159   RF (FPS_REGNUM, core_reg->freg.r_fsr);
 160   RF (FP0_REGNUM + 0, core_reg->freg.r_freg[0]);
 161   RF (FP0_REGNUM + 2, core_reg->freg.r_freg[2]);
 162   RF (FP0_REGNUM + 4, core_reg->freg.r_freg[4]);
 163   RF (FP0_REGNUM + 6, core_reg->freg.r_freg[6]);
 164   RF (LP0_REGNUM + 1, core_reg->freg.r_freg[1]);
 165   RF (LP0_REGNUM + 3, core_reg->freg.r_freg[3]);
 166   RF (LP0_REGNUM + 5, core_reg->freg.r_freg[5]);
 167   RF (LP0_REGNUM + 7, core_reg->freg.r_freg[7]);
 168   registers_fetched ();
 169 }
 170
 171 /* Register that we are able to handle ns32knbsd core file formats.
 172    FIXME: is this really bfd_target_unknown_flavour? */
 173
 174 static struct core_fns nat_core_fns =
 175 {
 176   bfd_target_unknown_flavour,           /* core_flavour */
 177   default_check_format,                 /* check_format */
 178   default_core_sniffer,                 /* core_sniffer */
 179   fetch_core_registers,                 /* core_read_registers */
 180   NULL                                  /* next */
 181 };
 182
 183 void
 184 _initialize_ns32knbsd_nat (void)
 185 {
 186   add_core_fns (&nat_core_fns);
 187 }
 188 \f
 189
 190 /*
 191  * kernel_u_size() is not helpful on NetBSD because
 192  * the "u" struct is NOT in the core dump file.
 193  */
 194
 195 #ifdef  FETCH_KCORE_REGISTERS
 196 /*
 197  * Get registers from a kernel crash dump or live kernel.
 198  * Called by kcore-nbsd.c:get_kcore_registers().
 199  */
 200 void
 201 fetch_kcore_registers (struct pcb *pcb)
 202 {
 203   struct switchframe sf;
 204   struct reg intreg;
 205   int dummy;
 206
 207   /* Integer registers */
 208   if (target_read_memory ((CORE_ADDR) pcb->pcb_ksp, (char *) &sf, sizeof sf))
 209     error ("Cannot read integer registers.");
 210
 211   /* We use the psr at kernel entry */
 212   if (target_read_memory ((CORE_ADDR) pcb->pcb_onstack, (char *) &intreg, sizeof intreg))
 213     error ("Cannot read processor status register.");
 214
 215   dummy = 0;
 216   RF (R0_REGNUM + 0, dummy);
 217   RF (R0_REGNUM + 1, dummy);
 218   RF (R0_REGNUM + 2, dummy);
 219   RF (R0_REGNUM + 3, sf.sf_r3);
 220   RF (R0_REGNUM + 4, sf.sf_r4);
 221   RF (R0_REGNUM + 5, sf.sf_r5);
 222   RF (R0_REGNUM + 6, sf.sf_r6);
 223   RF (R0_REGNUM + 7, sf.sf_r7);
 224
 225   dummy = pcb->pcb_kfp + 8;
 226   RF (SP_REGNUM, dummy);
 227   RF (FP_REGNUM, sf.sf_fp);
 228   RF (PC_REGNUM, sf.sf_pc);
 229   RF (PS_REGNUM, intreg.r_psr);
 230
 231   /* Floating point registers */
 232   RF (FPS_REGNUM, pcb->pcb_fsr);
 233   RF (FP0_REGNUM + 0, pcb->pcb_freg[0]);
 234   RF (FP0_REGNUM + 2, pcb->pcb_freg[2]);
 235   RF (FP0_REGNUM + 4, pcb->pcb_freg[4]);
 236   RF (FP0_REGNUM + 6, pcb->pcb_freg[6]);
 237   RF (LP0_REGNUM + 1, pcb->pcb_freg[1]);
 238   RF (LP0_REGNUM + 3, pcb->pcb_freg[3]);
 239   RF (LP0_REGNUM + 5, pcb->pcb_freg[5]);
 240   RF (LP0_REGNUM + 7, pcb->pcb_freg[7]);
 241   registers_fetched ();
 242 }
 243 #endif /* FETCH_KCORE_REGISTERS */
 244
 245 void
 246 clear_regs (void)
 247 {
 248   double zero = 0.0;
 249   int null = 0;
 250
 251   /* Integer registers */
 252   RF (R0_REGNUM + 0, null);
 253   RF (R0_REGNUM + 1, null);
 254   RF (R0_REGNUM + 2, null);
 255   RF (R0_REGNUM + 3, null);
 256   RF (R0_REGNUM + 4, null);
 257   RF (R0_REGNUM + 5, null);
 258   RF (R0_REGNUM + 6, null);
 259   RF (R0_REGNUM + 7, null);
 260
 261   RF (SP_REGNUM, null);
 262   RF (FP_REGNUM, null);
 263   RF (PC_REGNUM, null);
 264   RF (PS_REGNUM, null);
 265
 266   /* Floating point registers */
 267   RF (FPS_REGNUM, zero);
 268   RF (FP0_REGNUM + 0, zero);
 269   RF (FP0_REGNUM + 2, zero);
 270   RF (FP0_REGNUM + 4, zero);
 271   RF (FP0_REGNUM + 6, zero);
 272   RF (LP0_REGNUM + 0, zero);
 273   RF (LP0_REGNUM + 1, zero);
 274   RF (LP0_REGNUM + 2, zero);
 275   RF (LP0_REGNUM + 3, zero);
 276   return;
 277 }
 278
 279 /* Return number of args passed to a frame.
 280    Can return -1, meaning no way to tell. */
 281
 282 int
 283 frame_num_args (struct frame_info *fi)
 284 {
 285   CORE_ADDR enter_addr;
 286   CORE_ADDR argp;
 287   int inst;
 288   int args;
 289   int i;
 290
 291   if (read_memory_integer (fi->frame, 4) == 0 && fi->pc < 0x10000)
 292     {
 293       /* main is always called with three args */
 294       return (3);
 295     }
 296   enter_addr = ns32k_get_enter_addr (fi->pc);
 297   if (enter_addr = 0)
 298     return (-1);
 299   argp = enter_addr == 1 ? SAVED_PC_AFTER_CALL (fi) : FRAME_SAVED_PC (fi);
 300   for (i = 0; i < 16; i++)
 301     {
 302       /*
 303        * After a bsr gcc may emit the following instructions
 304        * to remove the arguments from the stack:
 305        *   cmpqd 0,tos        - to remove 4 bytes from the stack
 306        *   cmpd tos,tos       - to remove 8 bytes from the stack
 307        *   adjsp[bwd] -n      - to remove n bytes from the stack
 308        * Gcc sometimes delays emitting these instructions and
 309        * may even throw a branch between our feet.
 310        */
 311       inst = read_memory_integer (argp, 4);
 312       args = read_memory_integer (argp + 2, 4);
 313       if ((inst & 0xff) == 0xea)
 314         {                       /* br */
 315           args = ((inst >> 8) & 0xffffff) | (args << 24);
 316           if (args & 0x80)
 317             {
 318               if (args & 0x40)
 319                 {
 320                   args = ntohl (args);
 321                 }
 322               else
 323                 {
 324                   args = ntohs (args & 0xffff);
 325                   if (args & 0x2000)
 326                     args |= 0xc000;
 327                 }
 328             }
 329           else
 330             {
 331               args = args & 0xff;
 332               if (args & 0x40)
 333                 args |= 0x80;
 334             }
 335           argp += args;
 336           continue;
 337         }
 338       if ((inst & 0xffff) == 0xb81f)    /* cmpqd 0,tos */
 339         return (1);
 340       else if ((inst & 0xffff) == 0xbdc7)       /* cmpd tos,tos */
 341         return (2);
 342       else if ((inst & 0xfffc) == 0xa57c)
 343         {                       /* adjsp[bwd] */
 344           switch (inst & 3)
 345             {
 346             case 0:
 347               args = ((args & 0xff) + 0x80);
 348               break;
 349             case 1:
 350               args = ((ntohs (args) & 0xffff) + 0x8000);
 351               break;
 352             case 3:
 353               args = -ntohl (args);
 354               break;
 355             default:
 356               return (-1);
 357             }
 358           if (args / 4 > 10 || (args & 3) != 0)
 359             continue;
 360           return (args / 4);
 361         }
 362       argp += 1;
 363     }
 364   return (-1);
 365 }