gdb/gdbserver/lynx-i386-low.c

   1 /* Copyright (C) 2010-2018 Free Software Foundation, Inc.
   2
   3    This file is part of GDB.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 #include "server.h"
  19 #include "lynx-low.h"
  20 #include <limits.h>
  21 #include <sys/ptrace.h>
  22 #include "x86-xstate.h"
  23 #include "arch/i386.h"
  24 #include "x86-tdesc.h"
  25
  26 /* The following two typedefs are defined in a .h file which is not
  27    in the standard include path (/sys/include/family/x86/ucontext.h),
  28    so we just duplicate them here.  */
  29
  30 /* General register context */
  31 typedef struct usr_econtext {
  32
  33     uint32_t    uec_fault;
  34     uint32_t    uec_es;
  35     uint32_t    uec_ds;
  36     uint32_t    uec_edi;
  37     uint32_t    uec_esi;
  38     uint32_t    uec_ebp;
  39     uint32_t    uec_temp;
  40     uint32_t    uec_ebx;
  41     uint32_t    uec_edx;
  42     uint32_t    uec_ecx;
  43     uint32_t    uec_eax;
  44     uint32_t    uec_inum;
  45     uint32_t    uec_ecode;
  46     uint32_t    uec_eip;
  47     uint32_t    uec_cs;
  48     uint32_t    uec_eflags;
  49     uint32_t    uec_esp;
  50     uint32_t    uec_ss;
  51     uint32_t    uec_fs;
  52     uint32_t    uec_gs;
  53 } usr_econtext_t;
  54
  55 /* Floating point and SIMD register context */
  56 typedef struct usr_fcontext {
  57         uint16_t         ufc_control;
  58         uint16_t         ufc_status;
  59         uint16_t         ufc_tag;
  60         uint16_t         ufc_opcode;
  61         uint8_t         *ufc_inst_off;
  62         uint32_t         ufc_inst_sel;
  63         uint8_t         *ufc_data_off;
  64         uint32_t         ufc_data_sel;
  65         uint32_t         usse_mxcsr;
  66         uint32_t         usse_mxcsr_mask;
  67         struct ufp387_real {
  68                 uint16_t umant4;
  69                 uint16_t umant3;
  70                 uint16_t umant2;
  71                 uint16_t umant1;
  72                 uint16_t us_and_e;
  73                 uint16_t ureserved_1;
  74                 uint16_t ureserved_2;
  75                 uint16_t ureserved_3;
  76         } ufc_reg[8];
  77         struct uxmm_register {
  78                 uint16_t uchunk_1;
  79                 uint16_t uchunk_2;
  80                 uint16_t uchunk_3;
  81                 uint16_t uchunk_4;
  82                 uint16_t uchunk_5;
  83                 uint16_t uchunk_6;
  84                 uint16_t uchunk_7;
  85                 uint16_t uchunk_8;
  86         } uxmm_reg[8];
  87         char ureserved[16][14];
  88 } usr_fcontext_t;
  89
  90 /* The index of various registers inside the regcache.  */
  91
  92 enum lynx_i386_gdb_regnum
  93 {
  94   I386_EAX_REGNUM,
  95   I386_ECX_REGNUM,
  96   I386_EDX_REGNUM,
  97   I386_EBX_REGNUM,
  98   I386_ESP_REGNUM,
  99   I386_EBP_REGNUM,
 100   I386_ESI_REGNUM,
 101   I386_EDI_REGNUM,
 102   I386_EIP_REGNUM,
 103   I386_EFLAGS_REGNUM,
 104   I386_CS_REGNUM,
 105   I386_SS_REGNUM,
 106   I386_DS_REGNUM,
 107   I386_ES_REGNUM,
 108   I386_FS_REGNUM,
 109   I386_GS_REGNUM,
 110   I386_ST0_REGNUM,
 111   I386_FCTRL_REGNUM = I386_ST0_REGNUM + 8,
 112   I386_FSTAT_REGNUM,
 113   I386_FTAG_REGNUM,
 114   I386_FISEG_REGNUM,
 115   I386_FIOFF_REGNUM,
 116   I386_FOSEG_REGNUM,
 117   I386_FOOFF_REGNUM,
 118   I386_FOP_REGNUM,
 119   I386_XMM0_REGNUM = 32,
 120   I386_MXCSR_REGNUM = I386_XMM0_REGNUM + 8,
 121   I386_SENTINEL_REGUM
 122 };
 123
 124 /* The fill_function for the general-purpose register set.  */
 125
 126 static void
 127 lynx_i386_fill_gregset (struct regcache *regcache, char *buf)
 128 {
 129 #define lynx_i386_collect_gp(regnum, fld) \
 130   collect_register (regcache, regnum, \
 131                     buf + offsetof (usr_econtext_t, uec_##fld))
 132
 133   lynx_i386_collect_gp (I386_EAX_REGNUM, eax);
 134   lynx_i386_collect_gp (I386_ECX_REGNUM, ecx);
 135   lynx_i386_collect_gp (I386_EDX_REGNUM, edx);
 136   lynx_i386_collect_gp (I386_EBX_REGNUM, ebx);
 137   lynx_i386_collect_gp (I386_ESP_REGNUM, esp);
 138   lynx_i386_collect_gp (I386_EBP_REGNUM, ebp);
 139   lynx_i386_collect_gp (I386_ESI_REGNUM, esi);
 140   lynx_i386_collect_gp (I386_EDI_REGNUM, edi);
 141   lynx_i386_collect_gp (I386_EIP_REGNUM, eip);
 142   lynx_i386_collect_gp (I386_EFLAGS_REGNUM, eflags);
 143   lynx_i386_collect_gp (I386_CS_REGNUM, cs);
 144   lynx_i386_collect_gp (I386_SS_REGNUM, ss);
 145   lynx_i386_collect_gp (I386_DS_REGNUM, ds);
 146   lynx_i386_collect_gp (I386_ES_REGNUM, es);
 147   lynx_i386_collect_gp (I386_FS_REGNUM, fs);
 148   lynx_i386_collect_gp (I386_GS_REGNUM, gs);
 149 }
 150
 151 /* The store_function for the general-purpose register set.  */
 152
 153 static void
 154 lynx_i386_store_gregset (struct regcache *regcache, const char *buf)
 155 {
 156 #define lynx_i386_supply_gp(regnum, fld) \
 157   supply_register (regcache, regnum, \
 158                    buf + offsetof (usr_econtext_t, uec_##fld))
 159
 160   lynx_i386_supply_gp (I386_EAX_REGNUM, eax);
 161   lynx_i386_supply_gp (I386_ECX_REGNUM, ecx);
 162   lynx_i386_supply_gp (I386_EDX_REGNUM, edx);
 163   lynx_i386_supply_gp (I386_EBX_REGNUM, ebx);
 164   lynx_i386_supply_gp (I386_ESP_REGNUM, esp);
 165   lynx_i386_supply_gp (I386_EBP_REGNUM, ebp);
 166   lynx_i386_supply_gp (I386_ESI_REGNUM, esi);
 167   lynx_i386_supply_gp (I386_EDI_REGNUM, edi);
 168   lynx_i386_supply_gp (I386_EIP_REGNUM, eip);
 169   lynx_i386_supply_gp (I386_EFLAGS_REGNUM, eflags);
 170   lynx_i386_supply_gp (I386_CS_REGNUM, cs);
 171   lynx_i386_supply_gp (I386_SS_REGNUM, ss);
 172   lynx_i386_supply_gp (I386_DS_REGNUM, ds);
 173   lynx_i386_supply_gp (I386_ES_REGNUM, es);
 174   lynx_i386_supply_gp (I386_FS_REGNUM, fs);
 175   lynx_i386_supply_gp (I386_GS_REGNUM, gs);
 176 }
 177
 178 /* Extract the first 16 bits of register REGNUM in the REGCACHE,
 179    and store these 2 bytes at DEST.
 180
 181    This is useful to collect certain 16bit registers which are known
 182    by GDBserver as 32bit registers (such as the Control Register
 183    for instance).  */
 184
 185 static void
 186 collect_16bit_register (struct regcache *regcache, int regnum, char *dest)
 187 {
 188   gdb_byte word[4];
 189
 190   collect_register (regcache, regnum, word);
 191   memcpy (dest, word, 2);
 192 }
 193
 194 /* The fill_function for the floating-point register set.  */
 195
 196 static void
 197 lynx_i386_fill_fpregset (struct regcache *regcache, char *buf)
 198 {
 199   int i;
 200
 201   /* Collect %st0 .. %st7.  */
 202   for (i = 0; i < 8; i++)
 203     collect_register (regcache, I386_ST0_REGNUM + i,
 204                       buf + offsetof (usr_fcontext_t, ufc_reg)
 205                       + i * sizeof (struct ufp387_real));
 206
 207   /* Collect the other FPU registers.  */
 208   collect_16bit_register (regcache, I386_FCTRL_REGNUM,
 209                           buf + offsetof (usr_fcontext_t, ufc_control));
 210   collect_16bit_register (regcache, I386_FSTAT_REGNUM,
 211                           buf + offsetof (usr_fcontext_t, ufc_status));
 212   collect_16bit_register (regcache, I386_FTAG_REGNUM,
 213                           buf + offsetof (usr_fcontext_t, ufc_tag));
 214   collect_register (regcache, I386_FISEG_REGNUM,
 215                     buf + offsetof (usr_fcontext_t, ufc_inst_sel));
 216   collect_register (regcache, I386_FIOFF_REGNUM,
 217                     buf + offsetof (usr_fcontext_t, ufc_inst_off));
 218   collect_register (regcache, I386_FOSEG_REGNUM,
 219                     buf + offsetof (usr_fcontext_t, ufc_data_sel));
 220   collect_register (regcache, I386_FOOFF_REGNUM,
 221                     buf + offsetof (usr_fcontext_t, ufc_data_off));
 222   collect_16bit_register (regcache, I386_FOP_REGNUM,
 223                           buf + offsetof (usr_fcontext_t, ufc_opcode));
 224
 225   /* Collect the XMM registers.  */
 226   for (i = 0; i < 8; i++)
 227     collect_register (regcache, I386_XMM0_REGNUM + i,
 228                       buf + offsetof (usr_fcontext_t, uxmm_reg)
 229                       + i * sizeof (struct uxmm_register));
 230   collect_register (regcache, I386_MXCSR_REGNUM,
 231                     buf + offsetof (usr_fcontext_t, usse_mxcsr));
 232 }
 233
 234 /* This is the supply counterpart for collect_16bit_register:
 235    It extracts a 2byte value from BUF, and uses that value to
 236    set REGNUM's value in the regcache.
 237
 238    This is useful to supply the value of certain 16bit registers
 239    which are known by GDBserver as 32bit registers (such as the Control
 240    Register for instance).  */
 241
 242 static void
 243 supply_16bit_register (struct regcache *regcache, int regnum, const char *buf)
 244 {
 245   gdb_byte word[4];
 246
 247   memcpy (word, buf, 2);
 248   memset (word + 2, 0, 2);
 249   supply_register (regcache, regnum, word);
 250 }
 251
 252 /* The store_function for the floating-point register set.  */
 253
 254 static void
 255 lynx_i386_store_fpregset (struct regcache *regcache, const char *buf)
 256 {
 257   int i;
 258
 259   /* Store the %st0 .. %st7 registers.  */
 260   for (i = 0; i < 8; i++)
 261     supply_register (regcache, I386_ST0_REGNUM + i,
 262                      buf + offsetof (usr_fcontext_t, ufc_reg)
 263                      + i * sizeof (struct ufp387_real));
 264
 265   /* Store the other FPU registers.  */
 266   supply_16bit_register (regcache, I386_FCTRL_REGNUM,
 267                          buf + offsetof (usr_fcontext_t, ufc_control));
 268   supply_16bit_register (regcache, I386_FSTAT_REGNUM,
 269                          buf + offsetof (usr_fcontext_t, ufc_status));
 270   supply_16bit_register (regcache, I386_FTAG_REGNUM,
 271                          buf + offsetof (usr_fcontext_t, ufc_tag));
 272   supply_register (regcache, I386_FISEG_REGNUM,
 273                    buf + offsetof (usr_fcontext_t, ufc_inst_sel));
 274   supply_register (regcache, I386_FIOFF_REGNUM,
 275                    buf + offsetof (usr_fcontext_t, ufc_inst_off));
 276   supply_register (regcache, I386_FOSEG_REGNUM,
 277                    buf + offsetof (usr_fcontext_t, ufc_data_sel));
 278   supply_register (regcache, I386_FOOFF_REGNUM,
 279                    buf + offsetof (usr_fcontext_t, ufc_data_off));
 280   supply_16bit_register (regcache, I386_FOP_REGNUM,
 281                          buf + offsetof (usr_fcontext_t, ufc_opcode));
 282
 283   /* Store the XMM registers.  */
 284   for (i = 0; i < 8; i++)
 285     supply_register (regcache, I386_XMM0_REGNUM + i,
 286                      buf + offsetof (usr_fcontext_t, uxmm_reg)
 287                      + i * sizeof (struct uxmm_register));
 288   supply_register (regcache, I386_MXCSR_REGNUM,
 289                    buf + offsetof (usr_fcontext_t, usse_mxcsr));
 290 }
 291
 292 /* Implements the lynx_target_ops.arch_setup routine.  */
 293
 294 static void
 295 lynx_i386_arch_setup (void)
 296 {
 297   struct target_desc *tdesc
 298     = i386_create_target_description (X86_XSTATE_SSE_MASK, false);
 299
 300   init_target_desc (tdesc, i386_expedite_regs);
 301
 302   lynx_tdesc = tdesc;
 303 }
 304
 305 /* Description of all the x86-lynx register sets.  */
 306
 307 struct lynx_regset_info lynx_target_regsets[] = {
 308   /* General Purpose Registers.  */
 309   {PTRACE_GETREGS, PTRACE_SETREGS, sizeof(usr_econtext_t),
 310    lynx_i386_fill_gregset, lynx_i386_store_gregset},
 311   /* Floating Point Registers.  */
 312   { PTRACE_GETFPREGS, PTRACE_SETFPREGS, sizeof(usr_fcontext_t),
 313     lynx_i386_fill_fpregset, lynx_i386_store_fpregset },
 314   /* End of list marker.  */
 315   {0, 0, -1, NULL, NULL }
 316 };
 317
 318 /* The lynx_target_ops vector for x86-lynx.  */
 319
 320 struct lynx_target_ops the_low_target = {
 321   lynx_i386_arch_setup,
 322 };