gdbserver/linux-sparc-low.cc

   1 /* Low level interface to ptrace, for the remote server for GDB.
   2    Copyright (C) 1995-2022 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 "nat/gdb_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 /* Linux target op definitions for the SPARC architecture.  */
  46
  47 class sparc_target : public linux_process_target
  48 {
  49 public:
  50
  51   const regs_info *get_regs_info () override;
  52
  53   const gdb_byte *sw_breakpoint_from_kind (int kind, int *size) override;
  54
  55 protected:
  56
  57   void low_arch_setup () override;
  58
  59   bool low_cannot_fetch_register (int regno) override;
  60
  61   bool low_cannot_store_register (int regno) override;
  62
  63   bool low_supports_breakpoints () override;
  64
  65   CORE_ADDR low_get_pc (regcache *regcache) override;
  66
  67   /* No low_set_pc is needed.  */
  68
  69   bool low_breakpoint_at (CORE_ADDR pc) override;
  70 };
  71
  72 /* The singleton target ops object.  */
  73
  74 static sparc_target the_sparc_target;
  75
  76 bool
  77 sparc_target::low_supports_breakpoints ()
  78 {
  79   return true;
  80 }
  81
  82 CORE_ADDR
  83 sparc_target::low_get_pc (regcache *regcache)
  84 {
  85   return linux_get_pc_64bit (regcache);
  86 }
  87
  88 /* Each offset is multiplied by 8, because of the register size.
  89    These offsets apply to the buffer sent/filled by ptrace.
  90    Additionally, the array elements order corresponds to the .dat file, and the
  91    gdb's registers enumeration order.  */
  92
  93 static int sparc_regmap[] = {
  94   /* These offsets correspond to GET/SETREGSET.  */
  95         -1,  0*8,  1*8,  2*8,  3*8,  4*8,  5*8,  6*8,    /* g0 .. g7 */
  96         7*8,  8*8,  9*8, 10*8, 11*8, 12*8, 13*8, 14*8,   /* o0 .. o5, sp, o7 */
  97         -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,    /* l0 .. l7 */
  98         -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,    /* i0 .. i5, fp, i7 */
  99
 100   /* Floating point registers offsets correspond to GET/SETFPREGSET.  */
 101     0*4,  1*4,  2*4,  3*4,  4*4,  5*4,  6*4,  7*4,         /*  f0 ..  f7 */
 102     8*4,  9*4, 10*4, 11*4, 12*4, 13*4, 14*4, 15*4,         /*  f8 .. f15 */
 103    16*4, 17*4, 18*4, 19*4, 20*4, 21*4, 22*4, 23*4,         /* f16 .. f23 */
 104    24*4, 25*4, 26*4, 27*4, 28*4, 29*4, 30*4, 31*4,         /* f24 .. f31 */
 105
 106   /* F32 offset starts next to f31: 31*4+4 = 16 * 8.  */
 107    16*8, 17*8, 18*8, 19*8, 20*8, 21*8, 22*8, 23*8,         /* f32 .. f46 */
 108    24*8, 25*8, 26*8, 27*8, 28*8, 29*8, 30*8, 31*8,         /* f48 .. f62 */
 109
 110    17 *8, /*    pc */
 111    18 *8, /*   npc */
 112    16 *8, /* state */
 113   /* FSR offset also corresponds to GET/SETFPREGSET, ans is placed
 114      next to f62.  */
 115    32 *8, /*   fsr */
 116       -1, /*  fprs */
 117   /* Y register is 32-bits length, but gdb takes care of that.  */
 118    19 *8, /*     y */
 119
 120 };
 121
 122
 123 struct regs_range_t
 124 {
 125   int regno_start;
 126   int regno_end;
 127 };
 128
 129 static const struct regs_range_t gregs_ranges[] = {
 130  {  0, 31 }, /*   g0 .. i7  */
 131  { 80, 82 }, /*   pc .. state */
 132  { 84, 85 }  /* fprs .. y */
 133 };
 134
 135 #define N_GREGS_RANGES (sizeof (gregs_ranges) / sizeof (struct regs_range_t))
 136
 137 static const struct regs_range_t fpregs_ranges[] = {
 138  { 32, 79 }, /* f0 .. f62  */
 139  { 83, 83 }  /* fsr */
 140 };
 141
 142 #define N_FPREGS_RANGES (sizeof (fpregs_ranges) / sizeof (struct regs_range_t))
 143
 144 /* Defined in auto-generated file reg-sparc64.c.  */
 145 void init_registers_sparc64 (void);
 146 extern const struct target_desc *tdesc_sparc64;
 147
 148 bool
 149 sparc_target::low_cannot_store_register (int regno)
 150 {
 151   return (regno >= sparc_num_regs || sparc_regmap[regno] == -1);
 152 }
 153
 154 bool
 155 sparc_target::low_cannot_fetch_register (int regno)
 156 {
 157   return (regno >= sparc_num_regs || sparc_regmap[regno] == -1);
 158 }
 159
 160 static void
 161 sparc_fill_gregset_to_stack (struct regcache *regcache, const void *buf)
 162 {
 163   int i;
 164   CORE_ADDR addr = 0;
 165   unsigned char tmp_reg_buf[8];
 166   const int l0_regno = find_regno (regcache->tdesc, "l0");
 167   const int i7_regno = l0_regno + 15;
 168
 169   /* These registers have to be stored in the stack.  */
 170   memcpy (&addr,
 171           ((char *) buf) + sparc_regmap[find_regno (regcache->tdesc, "sp")],
 172           sizeof (addr));
 173
 174   addr += BIAS;
 175
 176   for (i = l0_regno; i <= i7_regno; i++)
 177     {
 178       collect_register (regcache, i, tmp_reg_buf);
 179       the_target->write_memory (addr, tmp_reg_buf, sizeof (tmp_reg_buf));
 180       addr += sizeof (tmp_reg_buf);
 181     }
 182 }
 183
 184 static void
 185 sparc_fill_gregset (struct regcache *regcache, void *buf)
 186 {
 187   int i;
 188   int range;
 189
 190   for (range = 0; range < N_GREGS_RANGES; range++)
 191     for (i = gregs_ranges[range].regno_start;
 192          i <= gregs_ranges[range].regno_end; i++)
 193       if (sparc_regmap[i] != -1)
 194         collect_register (regcache, i, ((char *) buf) + sparc_regmap[i]);
 195
 196   sparc_fill_gregset_to_stack (regcache, buf);
 197 }
 198
 199 static void
 200 sparc_fill_fpregset (struct regcache *regcache, void *buf)
 201 {
 202   int i;
 203   int range;
 204
 205   for (range = 0; range < N_FPREGS_RANGES; range++)
 206     for (i = fpregs_ranges[range].regno_start;
 207          i <= fpregs_ranges[range].regno_end; i++)
 208       collect_register (regcache, i, ((char *) buf) + sparc_regmap[i]);
 209
 210 }
 211
 212 static void
 213 sparc_store_gregset_from_stack (struct regcache *regcache, const void *buf)
 214 {
 215   int i;
 216   CORE_ADDR addr = 0;
 217   unsigned char tmp_reg_buf[8];
 218   const int l0_regno = find_regno (regcache->tdesc, "l0");
 219   const int i7_regno = l0_regno + 15;
 220
 221   /* These registers have to be obtained from the stack.  */
 222   memcpy (&addr,
 223           ((char *) buf) + sparc_regmap[find_regno (regcache->tdesc, "sp")],
 224           sizeof (addr));
 225
 226   addr += BIAS;
 227
 228   for (i = l0_regno; i <= i7_regno; i++)
 229     {
 230       the_target->read_memory (addr, tmp_reg_buf, sizeof (tmp_reg_buf));
 231       supply_register (regcache, i, tmp_reg_buf);
 232       addr += sizeof (tmp_reg_buf);
 233     }
 234 }
 235
 236 static void
 237 sparc_store_gregset (struct regcache *regcache, const void *buf)
 238 {
 239   int i;
 240   char zerobuf[8];
 241   int range;
 242
 243   memset (zerobuf, 0, sizeof (zerobuf));
 244
 245   for (range = 0; range < N_GREGS_RANGES; range++)
 246     for (i = gregs_ranges[range].regno_start;
 247          i <= gregs_ranges[range].regno_end; i++)
 248       if (sparc_regmap[i] != -1)
 249         supply_register (regcache, i, ((char *) buf) + sparc_regmap[i]);
 250       else
 251         supply_register (regcache, i, zerobuf);
 252
 253   sparc_store_gregset_from_stack (regcache, buf);
 254 }
 255
 256 static void
 257 sparc_store_fpregset (struct regcache *regcache, const void *buf)
 258 {
 259   int i;
 260   int range;
 261
 262   for (range = 0; range < N_FPREGS_RANGES; range++)
 263     for (i = fpregs_ranges[range].regno_start;
 264          i <= fpregs_ranges[range].regno_end;
 265          i++)
 266       supply_register (regcache, i, ((char *) buf) + sparc_regmap[i]);
 267 }
 268
 269 static const gdb_byte sparc_breakpoint[INSN_SIZE] = {
 270   0x91, 0xd0, 0x20, 0x01
 271 };
 272 #define sparc_breakpoint_len INSN_SIZE
 273
 274 /* Implementation of target ops method "sw_breakpoint_from_kind".  */
 275
 276 const gdb_byte *
 277 sparc_target::sw_breakpoint_from_kind (int kind, int *size)
 278 {
 279   *size = sparc_breakpoint_len;
 280   return sparc_breakpoint;
 281 }
 282
 283 bool
 284 sparc_target::low_breakpoint_at (CORE_ADDR where)
 285 {
 286   unsigned char insn[INSN_SIZE];
 287
 288   read_memory (where, (unsigned char *) insn, sizeof (insn));
 289
 290   if (memcmp (sparc_breakpoint, insn, sizeof (insn)) == 0)
 291     return true;
 292
 293   /* If necessary, recognize more trap instructions here.  GDB only
 294      uses TRAP Always.  */
 295
 296   return false;
 297 }
 298
 299 void
 300 sparc_target::low_arch_setup ()
 301 {
 302   current_process ()->tdesc = tdesc_sparc64;
 303 }
 304
 305 static struct regset_info sparc_regsets[] = {
 306   { PTRACE_GETREGS, PTRACE_SETREGS, 0, sizeof (elf_gregset_t),
 307     GENERAL_REGS,
 308     sparc_fill_gregset, sparc_store_gregset },
 309   { PTRACE_GETFPREGS, PTRACE_SETFPREGS, 0, sizeof (fpregset_t),
 310     FP_REGS,
 311     sparc_fill_fpregset, sparc_store_fpregset },
 312   NULL_REGSET
 313 };
 314
 315 static struct regsets_info sparc_regsets_info =
 316   {
 317     sparc_regsets, /* regsets */
 318     0, /* num_regsets */
 319     NULL, /* disabled_regsets */
 320   };
 321
 322 static struct usrregs_info sparc_usrregs_info =
 323   {
 324     sparc_num_regs,
 325     /* No regmap needs to be provided since this impl. doesn't use
 326        USRREGS.  */
 327     NULL
 328   };
 329
 330 static struct regs_info myregs_info =
 331   {
 332     NULL, /* regset_bitmap */
 333     &sparc_usrregs_info,
 334     &sparc_regsets_info
 335   };
 336
 337 const regs_info *
 338 sparc_target::get_regs_info ()
 339 {
 340   return &myregs_info;
 341 }
 342
 343 /* The linux target ops object.  */
 344
 345 linux_process_target *the_linux_target = &the_sparc_target;
 346
 347 void
 348 initialize_low_arch (void)
 349 {
 350   /* Initialize the Linux target descriptions.  */
 351   init_registers_sparc64 ();
 352
 353   initialize_regsets_info (&sparc_regsets_info);
 354 }