gdbserver/linux-sparc-low.cc

   1 /* Low level interface to ptrace, for the remote server for GDB.
   2    Copyright (C) 1995-2024 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 "linux-low.h"
  20
  21 #include "nat/gdb_ptrace.h"
  22
  23 #include "gdb_proc_service.h"
  24
  25 /* The stack pointer is offset from the stack frame by a BIAS of 2047
  26    (0x7ff) for 64-bit code.  BIAS is likely to be defined on SPARC
  27    hosts, so undefine it first.  */
  28 #undef BIAS
  29 #define BIAS 2047
  30
  31 #ifdef HAVE_SYS_REG_H
  32 #include <sys/reg.h>
  33 #endif
  34
  35 #define INSN_SIZE 4
  36
  37 #define SPARC_R_REGS_NUM 32
  38 #define SPARC_F_REGS_NUM 48
  39 #define SPARC_CONTROL_REGS_NUM 6
  40
  41 #define sparc_num_regs \
  42   (SPARC_R_REGS_NUM + SPARC_F_REGS_NUM + SPARC_CONTROL_REGS_NUM)
  43
  44 /* Linux target op definitions for the SPARC architecture.  */
  45
  46 class sparc_target : public linux_process_target
  47 {
  48 public:
  49
  50   const regs_info *get_regs_info () override;
  51
  52   const gdb_byte *sw_breakpoint_from_kind (int kind, int *size) override;
  53
  54 protected:
  55
  56   void low_arch_setup () override;
  57
  58   bool low_cannot_fetch_register (int regno) override;
  59
  60   bool low_cannot_store_register (int regno) override;
  61
  62   bool low_supports_breakpoints () override;
  63
  64   CORE_ADDR low_get_pc (regcache *regcache) override;
  65
  66   /* No low_set_pc is needed.  */
  67
  68   bool low_breakpoint_at (CORE_ADDR pc) override;
  69 };
  70
  71 /* The singleton target ops object.  */
  72
  73 static sparc_target the_sparc_target;
  74
  75 bool
  76 sparc_target::low_supports_breakpoints ()
  77 {
  78   return true;
  79 }
  80
  81 CORE_ADDR
  82 sparc_target::low_get_pc (regcache *regcache)
  83 {
  84   return linux_get_pc_64bit (regcache);
  85 }
  86
  87 /* Each offset is multiplied by 8, because of the register size.
  88    These offsets apply to the buffer sent/filled by ptrace.
  89    Additionally, the array elements order corresponds to the .dat file, and the
  90    gdb's registers enumeration order.  */
  91
  92 static int sparc_regmap[] = {
  93   /* These offsets correspond to GET/SETREGSET.  */
  94         -1,  0*8,  1*8,  2*8,  3*8,  4*8,  5*8,  6*8,    /* g0 .. g7 */
  95         7*8,  8*8,  9*8, 10*8, 11*8, 12*8, 13*8, 14*8,   /* o0 .. o5, sp, o7 */
  96         -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,    /* l0 .. l7 */
  97         -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,    /* i0 .. i5, fp, i7 */
  98
  99   /* Floating point registers offsets correspond to GET/SETFPREGSET.  */
 100     0*4,  1*4,  2*4,  3*4,  4*4,  5*4,  6*4,  7*4,         /*  f0 ..  f7 */
 101     8*4,  9*4, 10*4, 11*4, 12*4, 13*4, 14*4, 15*4,         /*  f8 .. f15 */
 102    16*4, 17*4, 18*4, 19*4, 20*4, 21*4, 22*4, 23*4,         /* f16 .. f23 */
 103    24*4, 25*4, 26*4, 27*4, 28*4, 29*4, 30*4, 31*4,         /* f24 .. f31 */
 104
 105   /* F32 offset starts next to f31: 31*4+4 = 16 * 8.  */
 106    16*8, 17*8, 18*8, 19*8, 20*8, 21*8, 22*8, 23*8,         /* f32 .. f46 */
 107    24*8, 25*8, 26*8, 27*8, 28*8, 29*8, 30*8, 31*8,         /* f48 .. f62 */
 108
 109    17 *8, /*    pc */
 110    18 *8, /*   npc */
 111    16 *8, /* state */
 112   /* FSR offset also corresponds to GET/SETFPREGSET, ans is placed
 113      next to f62.  */
 114    32 *8, /*   fsr */
 115       -1, /*  fprs */
 116   /* Y register is 32-bits length, but gdb takes care of that.  */
 117    19 *8, /*     y */
 118
 119 };
 120
 121
 122 struct regs_range_t
 123 {
 124   int regno_start;
 125   int regno_end;
 126 };
 127
 128 static const struct regs_range_t gregs_ranges[] = {
 129  {  0, 31 }, /*   g0 .. i7  */
 130  { 80, 82 }, /*   pc .. state */
 131  { 84, 85 }  /* fprs .. y */
 132 };
 133
 134 #define N_GREGS_RANGES (sizeof (gregs_ranges) / sizeof (struct regs_range_t))
 135
 136 static const struct regs_range_t fpregs_ranges[] = {
 137  { 32, 79 }, /* f0 .. f62  */
 138  { 83, 83 }  /* fsr */
 139 };
 140
 141 #define N_FPREGS_RANGES (sizeof (fpregs_ranges) / sizeof (struct regs_range_t))
 142
 143 /* Defined in auto-generated file reg-sparc64.c.  */
 144 void init_registers_sparc64 (void);
 145 extern const struct target_desc *tdesc_sparc64;
 146
 147 bool
 148 sparc_target::low_cannot_store_register (int regno)
 149 {
 150   return (regno >= sparc_num_regs || sparc_regmap[regno] == -1);
 151 }
 152
 153 bool
 154 sparc_target::low_cannot_fetch_register (int regno)
 155 {
 156   return (regno >= sparc_num_regs || sparc_regmap[regno] == -1);
 157 }
 158
 159 static void
 160 sparc_fill_gregset_to_stack (struct regcache *regcache, const void *buf)
 161 {
 162   int i;
 163   CORE_ADDR addr = 0;
 164   unsigned char tmp_reg_buf[8];
 165   const int l0_regno = find_regno (regcache->tdesc, "l0");
 166   const int i7_regno = l0_regno + 15;
 167
 168   /* These registers have to be stored in the stack.  */
 169   memcpy (&addr,
 170           ((char *) buf) + sparc_regmap[find_regno (regcache->tdesc, "sp")],
 171           sizeof (addr));
 172
 173   addr += BIAS;
 174
 175   for (i = l0_regno; i <= i7_regno; i++)
 176     {
 177       collect_register (regcache, i, tmp_reg_buf);
 178       the_target->write_memory (addr, tmp_reg_buf, sizeof (tmp_reg_buf));
 179       addr += sizeof (tmp_reg_buf);
 180     }
 181 }
 182
 183 static void
 184 sparc_fill_gregset (struct regcache *regcache, void *buf)
 185 {
 186   int i;
 187   int range;
 188
 189   for (range = 0; range < N_GREGS_RANGES; range++)
 190     for (i = gregs_ranges[range].regno_start;
 191          i <= gregs_ranges[range].regno_end; i++)
 192       if (sparc_regmap[i] != -1)
 193         collect_register (regcache, i, ((char *) buf) + sparc_regmap[i]);
 194
 195   sparc_fill_gregset_to_stack (regcache, buf);
 196 }
 197
 198 static void
 199 sparc_fill_fpregset (struct regcache *regcache, void *buf)
 200 {
 201   int i;
 202   int range;
 203
 204   for (range = 0; range < N_FPREGS_RANGES; range++)
 205     for (i = fpregs_ranges[range].regno_start;
 206          i <= fpregs_ranges[range].regno_end; i++)
 207       collect_register (regcache, i, ((char *) buf) + sparc_regmap[i]);
 208
 209 }
 210
 211 static void
 212 sparc_store_gregset_from_stack (struct regcache *regcache, const void *buf)
 213 {
 214   int i;
 215   CORE_ADDR addr = 0;
 216   unsigned char tmp_reg_buf[8];
 217   const int l0_regno = find_regno (regcache->tdesc, "l0");
 218   const int i7_regno = l0_regno + 15;
 219
 220   /* These registers have to be obtained from the stack.  */
 221   memcpy (&addr,
 222           ((char *) buf) + sparc_regmap[find_regno (regcache->tdesc, "sp")],
 223           sizeof (addr));
 224
 225   addr += BIAS;
 226
 227   for (i = l0_regno; i <= i7_regno; i++)
 228     {
 229       the_target->read_memory (addr, tmp_reg_buf, sizeof (tmp_reg_buf));
 230       supply_register (regcache, i, tmp_reg_buf);
 231       addr += sizeof (tmp_reg_buf);
 232     }
 233 }
 234
 235 static void
 236 sparc_store_gregset (struct regcache *regcache, const void *buf)
 237 {
 238   int i;
 239   char zerobuf[8];
 240   int range;
 241
 242   memset (zerobuf, 0, sizeof (zerobuf));
 243
 244   for (range = 0; range < N_GREGS_RANGES; range++)
 245     for (i = gregs_ranges[range].regno_start;
 246          i <= gregs_ranges[range].regno_end; i++)
 247       if (sparc_regmap[i] != -1)
 248         supply_register (regcache, i, ((char *) buf) + sparc_regmap[i]);
 249       else
 250         supply_register (regcache, i, zerobuf);
 251
 252   sparc_store_gregset_from_stack (regcache, buf);
 253 }
 254
 255 static void
 256 sparc_store_fpregset (struct regcache *regcache, const void *buf)
 257 {
 258   int i;
 259   int range;
 260
 261   for (range = 0; range < N_FPREGS_RANGES; range++)
 262     for (i = fpregs_ranges[range].regno_start;
 263          i <= fpregs_ranges[range].regno_end;
 264          i++)
 265       supply_register (regcache, i, ((char *) buf) + sparc_regmap[i]);
 266 }
 267
 268 static const gdb_byte sparc_breakpoint[INSN_SIZE] = {
 269   0x91, 0xd0, 0x20, 0x01
 270 };
 271 #define sparc_breakpoint_len INSN_SIZE
 272
 273 /* Implementation of target ops method "sw_breakpoint_from_kind".  */
 274
 275 const gdb_byte *
 276 sparc_target::sw_breakpoint_from_kind (int kind, int *size)
 277 {
 278   *size = sparc_breakpoint_len;
 279   return sparc_breakpoint;
 280 }
 281
 282 bool
 283 sparc_target::low_breakpoint_at (CORE_ADDR where)
 284 {
 285   unsigned char insn[INSN_SIZE];
 286
 287   read_memory (where, (unsigned char *) insn, sizeof (insn));
 288
 289   if (memcmp (sparc_breakpoint, insn, sizeof (insn)) == 0)
 290     return true;
 291
 292   /* If necessary, recognize more trap instructions here.  GDB only
 293      uses TRAP Always.  */
 294
 295   return false;
 296 }
 297
 298 void
 299 sparc_target::low_arch_setup ()
 300 {
 301   current_process ()->tdesc = tdesc_sparc64;
 302 }
 303
 304 static struct regset_info sparc_regsets[] = {
 305   { PTRACE_GETREGS, PTRACE_SETREGS, 0, sizeof (elf_gregset_t),
 306     GENERAL_REGS,
 307     sparc_fill_gregset, sparc_store_gregset },
 308   { PTRACE_GETFPREGS, PTRACE_SETFPREGS, 0, sizeof (fpregset_t),
 309     FP_REGS,
 310     sparc_fill_fpregset, sparc_store_fpregset },
 311   NULL_REGSET
 312 };
 313
 314 static struct regsets_info sparc_regsets_info =
 315   {
 316     sparc_regsets, /* regsets */
 317     0, /* num_regsets */
 318     NULL, /* disabled_regsets */
 319   };
 320
 321 static struct usrregs_info sparc_usrregs_info =
 322   {
 323     sparc_num_regs,
 324     /* No regmap needs to be provided since this impl. doesn't use
 325        USRREGS.  */
 326     NULL
 327   };
 328
 329 static struct regs_info myregs_info =
 330   {
 331     NULL, /* regset_bitmap */
 332     &sparc_usrregs_info,
 333     &sparc_regsets_info
 334   };
 335
 336 const regs_info *
 337 sparc_target::get_regs_info ()
 338 {
 339   return &myregs_info;
 340 }
 341
 342 /* The linux target ops object.  */
 343
 344 linux_process_target *the_linux_target = &the_sparc_target;
 345
 346 void
 347 initialize_low_arch (void)
 348 {
 349   /* Initialize the Linux target descriptions.  */
 350   init_registers_sparc64 ();
 351
 352   initialize_regsets_info (&sparc_regsets_info);
 353 }