gdb/gdbserver/linux-sparc-low.c

   1 /* Low level interface to ptrace, for the remote server for GDB.
   2    Copyright (C) 1995-2013 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 3 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, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include "server.h"
  20 #include "linux-low.h"
  21
  22 #include <sys/ptrace.h>
  23
  24 #include "gdb_proc_service.h"
  25
  26 /* The stack pointer is offset from the stack frame by a BIAS of 2047
  27    (0x7ff) for 64-bit code.  BIAS is likely to be defined on SPARC
  28    hosts, so undefine it first.  */
  29 #undef BIAS
  30 #define BIAS 2047
  31
  32 #ifdef HAVE_SYS_REG_H
  33 #include <sys/reg.h>
  34 #endif
  35
  36 #define INSN_SIZE 4
  37
  38 #define SPARC_R_REGS_NUM 32
  39 #define SPARC_F_REGS_NUM 48
  40 #define SPARC_CONTROL_REGS_NUM 6
  41
  42 #define sparc_num_regs \
  43   (SPARC_R_REGS_NUM + SPARC_F_REGS_NUM + SPARC_CONTROL_REGS_NUM)
  44
  45 /* Each offset is multiplied by 8, because of the register size.
  46    These offsets apply to the buffer sent/filled by ptrace.
  47    Additionally, the array elements order corresponds to the .dat file, and the
  48    gdb's registers enumeration order.  */
  49
  50 static int sparc_regmap[] = {
  51   /* These offsets correspond to GET/SETREGSET.  */
  52         -1,  0*8,  1*8,  2*8,  3*8,  4*8,  5*8,  6*8,    /* g0 .. g7 */
  53         7*8,  8*8,  9*8, 10*8, 11*8, 12*8, 13*8, 14*8,   /* o0 .. o5, sp, o7 */
  54         -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,    /* l0 .. l7 */
  55         -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,    /* i0 .. i5, fp, i7 */
  56
  57   /* Floating point registers offsets correspond to GET/SETFPREGSET.  */
  58     0*4,  1*4,  2*4,  3*4,  4*4,  5*4,  6*4,  7*4,         /*  f0 ..  f7 */
  59     8*4,  9*4, 10*4, 11*4, 12*4, 13*4, 14*4, 15*4,         /*  f8 .. f15 */
  60    16*4, 17*4, 18*4, 19*4, 20*4, 21*4, 22*4, 23*4,         /* f16 .. f23 */
  61    24*4, 25*4, 26*4, 27*4, 28*4, 29*4, 30*4, 31*4,         /* f24 .. f31 */
  62
  63   /* F32 offset starts next to f31: 31*4+4 = 16 * 8.  */
  64    16*8, 17*8, 18*8, 19*8, 20*8, 21*8, 22*8, 23*8,         /* f32 .. f46 */
  65    24*8, 25*8, 26*8, 27*8, 28*8, 29*8, 30*8, 31*8,         /* f48 .. f62 */
  66
  67    17 *8, /*    pc */
  68    18 *8, /*   npc */
  69    16 *8, /* state */
  70   /* FSR offset also corresponds to GET/SETFPREGSET, ans is placed
  71      next to f62.  */
  72    32 *8, /*   fsr */
  73       -1, /*  fprs */
  74   /* Y register is 32-bits length, but gdb takes care of that.  */
  75    19 *8, /*     y */
  76
  77 };
  78
  79
  80 struct regs_range_t
  81 {
  82   int regno_start;
  83   int regno_end;
  84 };
  85
  86 static const struct regs_range_t gregs_ranges[] = {
  87  {  0, 31 }, /*   g0 .. i7  */
  88  { 80, 82 }, /*   pc .. state */
  89  { 84, 85 }  /* fprs .. y */
  90 };
  91
  92 #define N_GREGS_RANGES (sizeof (gregs_ranges) / sizeof (struct regs_range_t))
  93
  94 static const struct regs_range_t fpregs_ranges[] = {
  95  { 32, 79 }, /* f0 .. f62  */
  96  { 83, 83 }  /* fsr */
  97 };
  98
  99 #define N_FPREGS_RANGES (sizeof (fpregs_ranges) / sizeof (struct regs_range_t))
 100
 101 /* Defined in auto-generated file reg-sparc64.c.  */
 102 void init_registers_sparc64 (void);
 103
 104 static int
 105 sparc_cannot_store_register (int regno)
 106 {
 107   return (regno >= sparc_num_regs || sparc_regmap[regno] == -1);
 108 }
 109
 110 static int
 111 sparc_cannot_fetch_register (int regno)
 112 {
 113   return (regno >= sparc_num_regs || sparc_regmap[regno] == -1);
 114 }
 115
 116 static void
 117 sparc_fill_gregset_to_stack (struct regcache *regcache, const void *buf)
 118 {
 119   int i;
 120   CORE_ADDR addr = 0;
 121   unsigned char tmp_reg_buf[8];
 122   const int l0_regno = find_regno ("l0");
 123   const int i7_regno = l0_regno + 15;
 124
 125   /* These registers have to be stored in the stack.  */
 126   memcpy (&addr,
 127           ((char *) buf) + sparc_regmap[find_regno ("sp")],
 128           sizeof (addr));
 129
 130   addr += BIAS;
 131
 132   for (i = l0_regno; i <= i7_regno; i++)
 133     {
 134       collect_register (regcache, i, tmp_reg_buf);
 135       (*the_target->write_memory) (addr, tmp_reg_buf, sizeof (tmp_reg_buf));
 136       addr += sizeof (tmp_reg_buf);
 137     }
 138 }
 139
 140 static void
 141 sparc_fill_gregset (struct regcache *regcache, void *buf)
 142 {
 143   int i;
 144   int range;
 145
 146   for (range = 0; range < N_GREGS_RANGES; range++)
 147     for (i = gregs_ranges[range].regno_start;
 148          i <= gregs_ranges[range].regno_end; i++)
 149       if (sparc_regmap[i] != -1)
 150         collect_register (regcache, i, ((char *) buf) + sparc_regmap[i]);
 151
 152   sparc_fill_gregset_to_stack (regcache, buf);
 153 }
 154
 155 static void
 156 sparc_fill_fpregset (struct regcache *regcache, void *buf)
 157 {
 158   int i;
 159   int range;
 160
 161   for (range = 0; range < N_FPREGS_RANGES; range++)
 162     for (i = fpregs_ranges[range].regno_start;
 163          i <= fpregs_ranges[range].regno_end; i++)
 164       collect_register (regcache, i, ((char *) buf) + sparc_regmap[i]);
 165
 166 }
 167
 168 static void
 169 sparc_store_gregset_from_stack (struct regcache *regcache, const void *buf)
 170 {
 171   int i;
 172   CORE_ADDR addr = 0;
 173   unsigned char tmp_reg_buf[8];
 174   const int l0_regno = find_regno ("l0");
 175   const int i7_regno = l0_regno + 15;
 176
 177   /* These registers have to be obtained from the stack.  */
 178   memcpy (&addr,
 179           ((char *) buf) + sparc_regmap[find_regno ("sp")],
 180           sizeof (addr));
 181
 182   addr += BIAS;
 183
 184   for (i = l0_regno; i <= i7_regno; i++)
 185     {
 186       (*the_target->read_memory) (addr, tmp_reg_buf, sizeof (tmp_reg_buf));
 187       supply_register (regcache, i, tmp_reg_buf);
 188       addr += sizeof (tmp_reg_buf);
 189     }
 190 }
 191
 192 static void
 193 sparc_store_gregset (struct regcache *regcache, const void *buf)
 194 {
 195   int i;
 196   char zerobuf[8];
 197   int range;
 198
 199   memset (zerobuf, 0, sizeof (zerobuf));
 200
 201   for (range = 0; range < N_GREGS_RANGES; range++)
 202     for (i = gregs_ranges[range].regno_start;
 203          i <= gregs_ranges[range].regno_end; i++)
 204       if (sparc_regmap[i] != -1)
 205         supply_register (regcache, i, ((char *) buf) + sparc_regmap[i]);
 206       else
 207         supply_register (regcache, i, zerobuf);
 208
 209   sparc_store_gregset_from_stack (regcache, buf);
 210 }
 211
 212 static void
 213 sparc_store_fpregset (struct regcache *regcache, const void *buf)
 214 {
 215   int i;
 216   int range;
 217
 218   for (range = 0; range < N_FPREGS_RANGES; range++)
 219     for (i = fpregs_ranges[range].regno_start;
 220          i <= fpregs_ranges[range].regno_end;
 221          i++)
 222       supply_register (regcache, i, ((char *) buf) + sparc_regmap[i]);
 223 }
 224
 225 extern int debug_threads;
 226
 227 static CORE_ADDR
 228 sparc_get_pc (struct regcache *regcache)
 229 {
 230   unsigned long pc;
 231   collect_register_by_name (regcache, "pc", &pc);
 232   if (debug_threads)
 233     fprintf (stderr, "stop pc is %08lx\n", pc);
 234   return pc;
 235 }
 236
 237 static const unsigned char sparc_breakpoint[INSN_SIZE] = {
 238   0x91, 0xd0, 0x20, 0x01
 239 };
 240 #define sparc_breakpoint_len INSN_SIZE
 241
 242
 243 static int
 244 sparc_breakpoint_at (CORE_ADDR where)
 245 {
 246   unsigned char insn[INSN_SIZE];
 247
 248   (*the_target->read_memory) (where, (unsigned char *) insn, sizeof (insn));
 249
 250   if (memcmp (sparc_breakpoint, insn, sizeof (insn)) == 0)
 251     return 1;
 252
 253   /* If necessary, recognize more trap instructions here.  GDB only
 254      uses TRAP Always.  */
 255
 256   return 0;
 257 }
 258
 259 /* We only place breakpoints in empty marker functions, and thread locking
 260    is outside of the function.  So rather than importing software single-step,
 261    we can just run until exit.  */
 262 static CORE_ADDR
 263 sparc_reinsert_addr (void)
 264 {
 265   struct regcache *regcache = get_thread_regcache (current_inferior, 1);
 266   CORE_ADDR lr;
 267   /* O7 is the equivalent to the 'lr' of other archs.  */
 268   collect_register_by_name (regcache, "o7", &lr);
 269   return lr;
 270 }
 271
 272
 273 struct regset_info target_regsets[] = {
 274   { PTRACE_GETREGS, PTRACE_SETREGS, 0, sizeof (elf_gregset_t),
 275     GENERAL_REGS,
 276     sparc_fill_gregset, sparc_store_gregset },
 277   { PTRACE_GETFPREGS, PTRACE_SETFPREGS, 0, sizeof (fpregset_t),
 278     FP_REGS,
 279     sparc_fill_fpregset, sparc_store_fpregset },
 280   { 0, 0, 0, -1, -1, NULL, NULL }
 281 };
 282
 283 struct linux_target_ops the_low_target = {
 284   init_registers_sparc64,
 285   sparc_num_regs,
 286   /* No regmap needs to be provided since this impl. doesn't use USRREGS.  */
 287   NULL,
 288   NULL,
 289   sparc_cannot_fetch_register,
 290   sparc_cannot_store_register,
 291   NULL, /* fetch_register */
 292   sparc_get_pc,
 293   /* No sparc_set_pc is needed.  */
 294   NULL,
 295   (const unsigned char *) sparc_breakpoint,
 296   sparc_breakpoint_len,
 297   sparc_reinsert_addr,
 298   0,
 299   sparc_breakpoint_at,
 300   NULL, NULL, NULL, NULL,
 301   NULL, NULL
 302 };