gdb/ppc-ravenscar-thread.c

   1 /* Ravenscar PowerPC target support.
   2
   3    Copyright (C) 2011-2020 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 3 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, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "gdbcore.h"
  22 #include "regcache.h"
  23 #include "ppc-tdep.h"
  24 #include "inferior.h"
  25 #include "ravenscar-thread.h"
  26 #include "ppc-ravenscar-thread.h"
  27
  28 #define NO_OFFSET -1
  29
  30 /* See ppc-tdep.h for register numbers.  */
  31
  32 static const int powerpc_context_offsets[] =
  33 {
  34   /* R0 - R32 */
  35   NO_OFFSET, 0,         4,         NO_OFFSET,
  36   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  37   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  38   NO_OFFSET, 8,         12,        16,
  39   20,        24,        28,        32,
  40   36,        40,        44,        48,
  41   52,        56,        60,        64,
  42   68,        72,        76,        80,
  43
  44   /* F0 - F31 */
  45   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  46   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  47   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  48   NO_OFFSET, NO_OFFSET, 96,        104,
  49   112,       120,       128,       136,
  50   144,       152,       160,       168,
  51   176,       184,       192,       200,
  52   208,       216,       224,       232,
  53
  54   /* PC, MSR, CR, LR */
  55   88,        NO_OFFSET, 84,        NO_OFFSET,
  56
  57   /* CTR, XER, FPSCR  */
  58   NO_OFFSET, NO_OFFSET, 240
  59 };
  60
  61 static const int e500_context_offsets[] =
  62 {
  63   /* R0 - R32 */
  64   NO_OFFSET, 4,         12,        NO_OFFSET,
  65   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  66   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  67   NO_OFFSET, 20,        28,        36,
  68   44,        52,        60,        68,
  69   76,        84,        92,        100,
  70   108,       116,       124,       132,
  71   140,       148,       156,       164,
  72
  73   /* F0 - F31 */
  74   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  75   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  76   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  77   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  78   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  79   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  80   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  81   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  82
  83   /* PC, MSR, CR, LR */
  84   172,       NO_OFFSET, 168,       NO_OFFSET,
  85
  86   /* CTR, XER, FPSCR, MQ  */
  87   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  88
  89   /* Upper R0-R32.  */
  90   NO_OFFSET, 0,         8,        NO_OFFSET,
  91   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  92   NO_OFFSET, NO_OFFSET, NO_OFFSET, NO_OFFSET,
  93   NO_OFFSET, 16,        24,        32,
  94   40,        48,        56,        64,
  95   72,        80,        88,        96,
  96   104,       112,       120,       128,
  97   136,       144,       152,       160,
  98
  99   /* ACC, FSCR */
 100   NO_OFFSET, 176
 101 };
 102
 103 /* The register layout info.  */
 104
 105 struct ravenscar_reg_info
 106 {
 107   /* A table providing the offset relative to the context structure
 108      where each register is saved.  */
 109   const int *context_offsets;
 110
 111   /* The number of elements in the context_offsets table above.  */
 112   int context_offsets_size;
 113 };
 114
 115 /* supply register REGNUM, which has been saved on REGISTER_ADDR, to the
 116    regcache.  */
 117
 118 static void
 119 supply_register_at_address (struct regcache *regcache, int regnum,
 120                             CORE_ADDR register_addr)
 121 {
 122   struct gdbarch *gdbarch = regcache->arch ();
 123   int buf_size = register_size (gdbarch, regnum);
 124   gdb_byte *buf;
 125
 126   buf = (gdb_byte *) alloca (buf_size);
 127   read_memory (register_addr, buf, buf_size);
 128   regcache->raw_supply (regnum, buf);
 129 }
 130
 131 /* Return true if, for a non-running thread, REGNUM has been saved on the
 132    Thread_Descriptor.  */
 133
 134 static int
 135 register_in_thread_descriptor_p (const struct ravenscar_reg_info *reg_info,
 136                                  int regnum)
 137 {
 138   return (regnum < reg_info->context_offsets_size
 139           && reg_info->context_offsets[regnum] != NO_OFFSET);
 140 }
 141
 142 /* to_fetch_registers when inferior_ptid is different from the running
 143    thread.  */
 144
 145 static void
 146 ppc_ravenscar_generic_fetch_registers
 147   (const struct ravenscar_reg_info *reg_info,
 148    struct regcache *regcache, int regnum)
 149 {
 150   struct gdbarch *gdbarch = regcache->arch ();
 151   const int num_regs = gdbarch_num_regs (gdbarch);
 152   int current_regnum;
 153   CORE_ADDR current_address;
 154   CORE_ADDR thread_descriptor_address;
 155
 156   /* The tid is the thread_id field, which is a pointer to the thread.  */
 157   thread_descriptor_address = (CORE_ADDR) inferior_ptid.tid ();
 158
 159   /* Read registers.  */
 160   for (current_regnum = 0; current_regnum < num_regs; current_regnum++)
 161     {
 162       if (register_in_thread_descriptor_p (reg_info, current_regnum))
 163         {
 164           current_address = thread_descriptor_address
 165             + reg_info->context_offsets[current_regnum];
 166           supply_register_at_address (regcache, current_regnum,
 167                                       current_address);
 168         }
 169     }
 170 }
 171
 172 /* to_store_registers when inferior_ptid is different from the running
 173    thread.  */
 174
 175 static void
 176 ppc_ravenscar_generic_store_registers
 177   (const struct ravenscar_reg_info *reg_info,
 178    struct regcache *regcache, int regnum)
 179 {
 180   struct gdbarch *gdbarch = regcache->arch ();
 181   int buf_size = register_size (gdbarch, regnum);
 182   gdb_byte buf[buf_size];
 183   ULONGEST register_address;
 184
 185   if (register_in_thread_descriptor_p (reg_info, regnum))
 186     register_address
 187       = inferior_ptid.tid () + reg_info->context_offsets [regnum];
 188   else
 189     return;
 190
 191   regcache->raw_collect (regnum, buf);
 192   write_memory (register_address,
 193                 buf,
 194                 buf_size);
 195 }
 196
 197 /* The ravenscar_reg_info for most PowerPC targets.  */
 198
 199 static const struct ravenscar_reg_info ppc_reg_info =
 200 {
 201   powerpc_context_offsets,
 202   ARRAY_SIZE (powerpc_context_offsets),
 203 };
 204
 205 struct ppc_ravenscar_powerpc_ops : public ravenscar_arch_ops
 206 {
 207   void fetch_registers (struct regcache *, int) override;
 208   void store_registers (struct regcache *, int) override;
 209 };
 210
 211 void
 212 ppc_ravenscar_powerpc_ops::fetch_registers (struct regcache *regcache, int regnum)
 213 {
 214   ppc_ravenscar_generic_fetch_registers (&ppc_reg_info, regcache, regnum);
 215 }
 216
 217 void
 218 ppc_ravenscar_powerpc_ops::store_registers (struct regcache *regcache, int regnum)
 219 {
 220   ppc_ravenscar_generic_store_registers (&ppc_reg_info, regcache, regnum);
 221 }
 222
 223 /* The ravenscar_arch_ops vector for most PowerPC targets.  */
 224
 225 static struct ppc_ravenscar_powerpc_ops ppc_ravenscar_powerpc_ops;
 226
 227 /* Register ppc_ravenscar_powerpc_ops in GDBARCH.  */
 228
 229 void
 230 register_ppc_ravenscar_ops (struct gdbarch *gdbarch)
 231 {
 232   set_gdbarch_ravenscar_ops (gdbarch, &ppc_ravenscar_powerpc_ops);
 233 }
 234
 235 /* The ravenscar_reg_info for E500 targets.  */
 236
 237 static const struct ravenscar_reg_info e500_reg_info =
 238 {
 239   e500_context_offsets,
 240   ARRAY_SIZE (e500_context_offsets),
 241 };
 242
 243 struct ppc_ravenscar_e500_ops : public ravenscar_arch_ops
 244 {
 245   void fetch_registers (struct regcache *, int) override;
 246   void store_registers (struct regcache *, int) override;
 247 };
 248
 249 void
 250 ppc_ravenscar_e500_ops::fetch_registers (struct regcache *regcache, int regnum)
 251 {
 252   ppc_ravenscar_generic_fetch_registers (&e500_reg_info, regcache, regnum);
 253 }
 254
 255 /* Implement the to_store_registers ravenscar_arch_ops method
 256    for E500 targets.  */
 257
 258 void
 259 ppc_ravenscar_e500_ops::store_registers (struct regcache *regcache, int regnum)
 260 {
 261   ppc_ravenscar_generic_store_registers (&e500_reg_info, regcache, regnum);
 262 }
 263
 264 /* The ravenscar_arch_ops vector for E500 targets.  */
 265
 266 static struct ppc_ravenscar_e500_ops ppc_ravenscar_e500_ops;
 267
 268 /* Register ppc_ravenscar_e500_ops in GDBARCH.  */
 269
 270 void
 271 register_e500_ravenscar_ops (struct gdbarch *gdbarch)
 272 {
 273   set_gdbarch_ravenscar_ops (gdbarch, &ppc_ravenscar_e500_ops);
 274 }