gdb/gdbserver/linux-amd64-ipa.c

   1 /* GNU/Linux/x86-64 specific low level interface, for the in-process
   2    agent library for GDB.
   3
   4    Copyright (C) 2010-2016 Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "server.h"
  22 #include <sys/mman.h>
  23 #include "tracepoint.h"
  24 #include "linux-x86-tdesc.h"
  25
  26 /* Defined in auto-generated file amd64-linux.c.  */
  27 void init_registers_amd64_linux (void);
  28 extern const struct target_desc *tdesc_amd64_linux;
  29
  30 /* fast tracepoints collect registers.  */
  31
  32 #define FT_CR_RIP 0
  33 #define FT_CR_EFLAGS 1
  34 #define FT_CR_R8 2
  35 #define FT_CR_R9 3
  36 #define FT_CR_R10 4
  37 #define FT_CR_R11 5
  38 #define FT_CR_R12 6
  39 #define FT_CR_R13 7
  40 #define FT_CR_R14 8
  41 #define FT_CR_R15 9
  42 #define FT_CR_RAX 10
  43 #define FT_CR_RBX 11
  44 #define FT_CR_RCX 12
  45 #define FT_CR_RDX 13
  46 #define FT_CR_RSI 14
  47 #define FT_CR_RDI 15
  48 #define FT_CR_RBP 16
  49 #define FT_CR_RSP 17
  50
  51 static const int x86_64_ft_collect_regmap[] = {
  52   FT_CR_RAX * 8, FT_CR_RBX * 8, FT_CR_RCX * 8, FT_CR_RDX * 8,
  53   FT_CR_RSI * 8, FT_CR_RDI * 8, FT_CR_RBP * 8, FT_CR_RSP * 8,
  54   FT_CR_R8 * 8,  FT_CR_R9 * 8,  FT_CR_R10 * 8, FT_CR_R11 * 8,
  55   FT_CR_R12 * 8, FT_CR_R13 * 8, FT_CR_R14 * 8, FT_CR_R15 * 8,
  56   FT_CR_RIP * 8, FT_CR_EFLAGS * 8
  57 };
  58
  59 #define X86_64_NUM_FT_COLLECT_GREGS \
  60   (sizeof (x86_64_ft_collect_regmap) / sizeof(x86_64_ft_collect_regmap[0]))
  61
  62 void
  63 supply_fast_tracepoint_registers (struct regcache *regcache,
  64                                   const unsigned char *buf)
  65 {
  66   int i;
  67
  68   for (i = 0; i < X86_64_NUM_FT_COLLECT_GREGS; i++)
  69     supply_register (regcache, i,
  70                      ((char *) buf) + x86_64_ft_collect_regmap[i]);
  71 }
  72
  73 ULONGEST
  74 get_raw_reg (const unsigned char *raw_regs, int regnum)
  75 {
  76   if (regnum >= X86_64_NUM_FT_COLLECT_GREGS)
  77     return 0;
  78
  79   return *(ULONGEST *) (raw_regs + x86_64_ft_collect_regmap[regnum]);
  80 }
  81
  82 #ifdef HAVE_UST
  83
  84 #include <ust/processor.h>
  85
  86 /* "struct registers" is the UST object type holding the registers at
  87    the time of the static tracepoint marker call.  This doesn't
  88    contain RIP, but we know what it must have been (the marker
  89    address).  */
  90
  91 #define ST_REGENTRY(REG)                        \
  92   {                                             \
  93     offsetof (struct registers, REG),           \
  94     sizeof (((struct registers *) NULL)->REG)   \
  95   }
  96
  97 static struct
  98 {
  99   int offset;
 100   int size;
 101 } x86_64_st_collect_regmap[] =
 102   {
 103     ST_REGENTRY(rax),
 104     ST_REGENTRY(rbx),
 105     ST_REGENTRY(rcx),
 106     ST_REGENTRY(rdx),
 107     ST_REGENTRY(rsi),
 108     ST_REGENTRY(rdi),
 109     ST_REGENTRY(rbp),
 110     ST_REGENTRY(rsp),
 111     ST_REGENTRY(r8),
 112     ST_REGENTRY(r9),
 113     ST_REGENTRY(r10),
 114     ST_REGENTRY(r11),
 115     ST_REGENTRY(r12),
 116     ST_REGENTRY(r13),
 117     ST_REGENTRY(r14),
 118     ST_REGENTRY(r15),
 119     { -1, 0 },
 120     ST_REGENTRY(rflags),
 121     ST_REGENTRY(cs),
 122     ST_REGENTRY(ss),
 123   };
 124
 125 #define X86_64_NUM_ST_COLLECT_GREGS \
 126   (sizeof (x86_64_st_collect_regmap) / sizeof (x86_64_st_collect_regmap[0]))
 127
 128 /* GDB's RIP register number.  */
 129 #define AMD64_RIP_REGNUM 16
 130
 131 void
 132 supply_static_tracepoint_registers (struct regcache *regcache,
 133                                     const unsigned char *buf,
 134                                     CORE_ADDR pc)
 135 {
 136   int i;
 137   unsigned long newpc = pc;
 138
 139   supply_register (regcache, AMD64_RIP_REGNUM, &newpc);
 140
 141   for (i = 0; i < X86_64_NUM_ST_COLLECT_GREGS; i++)
 142     if (x86_64_st_collect_regmap[i].offset != -1)
 143       {
 144         switch (x86_64_st_collect_regmap[i].size)
 145           {
 146           case 8:
 147             supply_register (regcache, i,
 148                              ((char *) buf)
 149                              + x86_64_st_collect_regmap[i].offset);
 150             break;
 151           case 2:
 152             {
 153               unsigned long reg
 154                 = * (short *) (((char *) buf)
 155                                + x86_64_st_collect_regmap[i].offset);
 156               reg &= 0xffff;
 157               supply_register (regcache, i, &reg);
 158             }
 159             break;
 160           default:
 161             internal_error (__FILE__, __LINE__,
 162                             "unhandled register size: %d",
 163                             x86_64_st_collect_regmap[i].size);
 164             break;
 165           }
 166       }
 167 }
 168
 169 #endif /* HAVE_UST */
 170
 171 /* Return target_desc to use for IPA, given the tdesc index passed by
 172    gdbserver.  */
 173
 174 const struct target_desc *
 175 get_ipa_tdesc (int idx)
 176 {
 177   switch (idx)
 178     {
 179     case X86_TDESC_SSE:
 180       return tdesc_amd64_linux;
 181     case X86_TDESC_AVX:
 182       return tdesc_amd64_avx_linux;
 183     case X86_TDESC_MPX:
 184       return tdesc_amd64_mpx_linux;
 185     case X86_TDESC_AVX512:
 186       return tdesc_amd64_avx512_linux;
 187     default:
 188       internal_error (__FILE__, __LINE__,
 189                       "unknown ipa tdesc index: %d", idx);
 190       return tdesc_amd64_linux;
 191     }
 192 }
 193
 194 /* Allocate buffer for the jump pads.  Since we're using 32-bit jumps
 195    to reach them, and the executable is at low addresses, MAP_32BIT
 196    works just fine.  Shared libraries, being allocated at the top,
 197    are unfortunately out of luck.  */
 198
 199 void *
 200 alloc_jump_pad_buffer (size_t size)
 201 {
 202   void *res = mmap (NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC,
 203                     MAP_PRIVATE | MAP_ANONYMOUS | MAP_32BIT, -1, 0);
 204
 205   if (res == MAP_FAILED)
 206     return NULL;
 207
 208   return res;
 209 }
 210
 211 void
 212 initialize_low_tracepoint (void)
 213 {
 214   init_registers_amd64_linux ();
 215   init_registers_amd64_avx_linux ();
 216   init_registers_amd64_mpx_linux ();
 217   init_registers_amd64_avx512_linux ();
 218 }