| 1 | /* Target-dependent code for the IA-64 for GDB, the GNU debugger. |
| 2 | |
| 3 | Copyright (C) 2000-2019 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 "ia64-tdep.h" |
| 22 | #include "arch-utils.h" |
| 23 | #include "gdbcore.h" |
| 24 | #include "regcache.h" |
| 25 | #include "osabi.h" |
| 26 | #include "solib-svr4.h" |
| 27 | #include "symtab.h" |
| 28 | #include "linux-tdep.h" |
| 29 | #include "regset.h" |
| 30 | |
| 31 | #include <ctype.h> |
| 32 | |
| 33 | /* The sigtramp code is in a non-readable (executable-only) region |
| 34 | of memory called the ``gate page''. The addresses in question |
| 35 | were determined by examining the system headers. They are |
| 36 | overly generous to allow for different pages sizes. */ |
| 37 | |
| 38 | #define GATE_AREA_START 0xa000000000000100LL |
| 39 | #define GATE_AREA_END 0xa000000000020000LL |
| 40 | |
| 41 | /* Offset to sigcontext structure from frame of handler. */ |
| 42 | #define IA64_LINUX_SIGCONTEXT_OFFSET 192 |
| 43 | |
| 44 | static int |
| 45 | ia64_linux_pc_in_sigtramp (CORE_ADDR pc) |
| 46 | { |
| 47 | return (pc >= (CORE_ADDR) GATE_AREA_START && pc < (CORE_ADDR) GATE_AREA_END); |
| 48 | } |
| 49 | |
| 50 | /* IA-64 GNU/Linux specific function which, given a frame address and |
| 51 | a register number, returns the address at which that register may be |
| 52 | found. 0 is returned for registers which aren't stored in the |
| 53 | sigcontext structure. */ |
| 54 | |
| 55 | static CORE_ADDR |
| 56 | ia64_linux_sigcontext_register_address (struct gdbarch *gdbarch, |
| 57 | CORE_ADDR sp, int regno) |
| 58 | { |
| 59 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 60 | gdb_byte buf[8]; |
| 61 | CORE_ADDR sigcontext_addr = 0; |
| 62 | |
| 63 | /* The address of the sigcontext area is found at offset 16 in the |
| 64 | sigframe. */ |
| 65 | read_memory (sp + 16, buf, 8); |
| 66 | sigcontext_addr = extract_unsigned_integer (buf, 8, byte_order); |
| 67 | |
| 68 | if (IA64_GR0_REGNUM <= regno && regno <= IA64_GR31_REGNUM) |
| 69 | return sigcontext_addr + 200 + 8 * (regno - IA64_GR0_REGNUM); |
| 70 | else if (IA64_BR0_REGNUM <= regno && regno <= IA64_BR7_REGNUM) |
| 71 | return sigcontext_addr + 136 + 8 * (regno - IA64_BR0_REGNUM); |
| 72 | else if (IA64_FR0_REGNUM <= regno && regno <= IA64_FR127_REGNUM) |
| 73 | return sigcontext_addr + 464 + 16 * (regno - IA64_FR0_REGNUM); |
| 74 | else |
| 75 | switch (regno) |
| 76 | { |
| 77 | case IA64_IP_REGNUM : |
| 78 | return sigcontext_addr + 40; |
| 79 | case IA64_CFM_REGNUM : |
| 80 | return sigcontext_addr + 48; |
| 81 | case IA64_PSR_REGNUM : |
| 82 | return sigcontext_addr + 56; /* user mask only */ |
| 83 | /* sc_ar_rsc is provided, from which we could compute bspstore, but |
| 84 | I don't think it's worth it. Anyway, if we want it, it's at offset |
| 85 | 64. */ |
| 86 | case IA64_BSP_REGNUM : |
| 87 | return sigcontext_addr + 72; |
| 88 | case IA64_RNAT_REGNUM : |
| 89 | return sigcontext_addr + 80; |
| 90 | case IA64_CCV_REGNUM : |
| 91 | return sigcontext_addr + 88; |
| 92 | case IA64_UNAT_REGNUM : |
| 93 | return sigcontext_addr + 96; |
| 94 | case IA64_FPSR_REGNUM : |
| 95 | return sigcontext_addr + 104; |
| 96 | case IA64_PFS_REGNUM : |
| 97 | return sigcontext_addr + 112; |
| 98 | case IA64_LC_REGNUM : |
| 99 | return sigcontext_addr + 120; |
| 100 | case IA64_PR_REGNUM : |
| 101 | return sigcontext_addr + 128; |
| 102 | default : |
| 103 | return 0; |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | static void |
| 108 | ia64_linux_write_pc (struct regcache *regcache, CORE_ADDR pc) |
| 109 | { |
| 110 | ia64_write_pc (regcache, pc); |
| 111 | |
| 112 | /* We must be careful with modifying the instruction-pointer: if we |
| 113 | just interrupt a system call, the kernel would ordinarily try to |
| 114 | restart it when we resume the inferior, which typically results |
| 115 | in SIGSEGV or SIGILL. We prevent this by clearing r10, which |
| 116 | will tell the kernel that r8 does NOT contain a valid error code |
| 117 | and hence it will skip system-call restart. |
| 118 | |
| 119 | The clearing of r10 is safe as long as ia64_write_pc() is only |
| 120 | called as part of setting up an inferior call. */ |
| 121 | regcache_cooked_write_unsigned (regcache, IA64_GR10_REGNUM, 0); |
| 122 | } |
| 123 | |
| 124 | /* Implementation of `gdbarch_stap_is_single_operand', as defined in |
| 125 | gdbarch.h. */ |
| 126 | |
| 127 | static int |
| 128 | ia64_linux_stap_is_single_operand (struct gdbarch *gdbarch, const char *s) |
| 129 | { |
| 130 | return ((isdigit (*s) && s[1] == '[' && s[2] == 'r') /* Displacement. */ |
| 131 | || *s == 'r' /* Register value. */ |
| 132 | || isdigit (*s)); /* Literal number. */ |
| 133 | } |
| 134 | |
| 135 | /* Core file support. */ |
| 136 | |
| 137 | static const struct regcache_map_entry ia64_linux_gregmap[] = |
| 138 | { |
| 139 | { 32, IA64_GR0_REGNUM, 8 }, /* r0 ... r31 */ |
| 140 | { 1, REGCACHE_MAP_SKIP, 8 }, /* FIXME: NAT collection bits? */ |
| 141 | { 1, IA64_PR_REGNUM, 8 }, |
| 142 | { 8, IA64_BR0_REGNUM, 8 }, /* b0 ... b7 */ |
| 143 | { 1, IA64_IP_REGNUM, 8 }, |
| 144 | { 1, IA64_CFM_REGNUM, 8 }, |
| 145 | { 1, IA64_PSR_REGNUM, 8 }, |
| 146 | { 1, IA64_RSC_REGNUM, 8 }, |
| 147 | { 1, IA64_BSP_REGNUM, 8 }, |
| 148 | { 1, IA64_BSPSTORE_REGNUM, 8 }, |
| 149 | { 1, IA64_RNAT_REGNUM, 8 }, |
| 150 | { 1, IA64_CCV_REGNUM, 8 }, |
| 151 | { 1, IA64_UNAT_REGNUM, 8 }, |
| 152 | { 1, IA64_FPSR_REGNUM, 8 }, |
| 153 | { 1, IA64_PFS_REGNUM, 8 }, |
| 154 | { 1, IA64_LC_REGNUM, 8 }, |
| 155 | { 1, IA64_EC_REGNUM, 8 }, |
| 156 | { 0 } |
| 157 | }; |
| 158 | |
| 159 | /* Size of 'gregset_t', as defined by the Linux kernel. Note that |
| 160 | this is more than actually mapped in the regmap above. */ |
| 161 | |
| 162 | #define IA64_LINUX_GREGS_SIZE (128 * 8) |
| 163 | |
| 164 | static const struct regcache_map_entry ia64_linux_fpregmap[] = |
| 165 | { |
| 166 | { 128, IA64_FR0_REGNUM, 16 }, /* f0 ... f127 */ |
| 167 | { 0 } |
| 168 | }; |
| 169 | |
| 170 | #define IA64_LINUX_FPREGS_SIZE (128 * 16) |
| 171 | |
| 172 | static void |
| 173 | ia64_linux_supply_fpregset (const struct regset *regset, |
| 174 | struct regcache *regcache, |
| 175 | int regnum, const void *regs, size_t len) |
| 176 | { |
| 177 | const gdb_byte f_zero[16] = { 0 }; |
| 178 | const gdb_byte f_one[16] = |
| 179 | { 0, 0, 0, 0, 0, 0, 0, 0x80, 0xff, 0xff, 0, 0, 0, 0, 0, 0 }; |
| 180 | |
| 181 | regcache_supply_regset (regset, regcache, regnum, regs, len); |
| 182 | |
| 183 | /* Kernel generated cores have fr1==0 instead of 1.0. Older GDBs |
| 184 | did the same. So ignore whatever might be recorded in fpregset_t |
| 185 | for fr0/fr1 and always supply their expected values. */ |
| 186 | if (regnum == -1 || regnum == IA64_FR0_REGNUM) |
| 187 | regcache->raw_supply (IA64_FR0_REGNUM, f_zero); |
| 188 | if (regnum == -1 || regnum == IA64_FR1_REGNUM) |
| 189 | regcache->raw_supply (IA64_FR1_REGNUM, f_one); |
| 190 | } |
| 191 | |
| 192 | static const struct regset ia64_linux_gregset = |
| 193 | { |
| 194 | ia64_linux_gregmap, |
| 195 | regcache_supply_regset, regcache_collect_regset |
| 196 | }; |
| 197 | |
| 198 | static const struct regset ia64_linux_fpregset = |
| 199 | { |
| 200 | ia64_linux_fpregmap, |
| 201 | ia64_linux_supply_fpregset, regcache_collect_regset |
| 202 | }; |
| 203 | |
| 204 | static void |
| 205 | ia64_linux_iterate_over_regset_sections (struct gdbarch *gdbarch, |
| 206 | iterate_over_regset_sections_cb *cb, |
| 207 | void *cb_data, |
| 208 | const struct regcache *regcache) |
| 209 | { |
| 210 | cb (".reg", IA64_LINUX_GREGS_SIZE, IA64_LINUX_GREGS_SIZE, &ia64_linux_gregset, |
| 211 | NULL, cb_data); |
| 212 | cb (".reg2", IA64_LINUX_FPREGS_SIZE, IA64_LINUX_FPREGS_SIZE, |
| 213 | &ia64_linux_fpregset, NULL, cb_data); |
| 214 | } |
| 215 | |
| 216 | static void |
| 217 | ia64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 218 | { |
| 219 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 220 | static const char *const stap_register_prefixes[] = { "r", NULL }; |
| 221 | static const char *const stap_register_indirection_prefixes[] = { "[", |
| 222 | NULL }; |
| 223 | static const char *const stap_register_indirection_suffixes[] = { "]", |
| 224 | NULL }; |
| 225 | |
| 226 | linux_init_abi (info, gdbarch); |
| 227 | |
| 228 | /* Set the method of obtaining the sigcontext addresses at which |
| 229 | registers are saved. */ |
| 230 | tdep->sigcontext_register_address = ia64_linux_sigcontext_register_address; |
| 231 | |
| 232 | /* Set the pc_in_sigtramp method. */ |
| 233 | tdep->pc_in_sigtramp = ia64_linux_pc_in_sigtramp; |
| 234 | |
| 235 | set_gdbarch_write_pc (gdbarch, ia64_linux_write_pc); |
| 236 | |
| 237 | set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target); |
| 238 | |
| 239 | set_solib_svr4_fetch_link_map_offsets |
| 240 | (gdbarch, svr4_lp64_fetch_link_map_offsets); |
| 241 | |
| 242 | /* Enable TLS support. */ |
| 243 | set_gdbarch_fetch_tls_load_module_address (gdbarch, |
| 244 | svr4_fetch_objfile_link_map); |
| 245 | |
| 246 | /* Core file support. */ |
| 247 | set_gdbarch_iterate_over_regset_sections |
| 248 | (gdbarch, ia64_linux_iterate_over_regset_sections); |
| 249 | |
| 250 | /* SystemTap related. */ |
| 251 | set_gdbarch_stap_register_prefixes (gdbarch, stap_register_prefixes); |
| 252 | set_gdbarch_stap_register_indirection_prefixes (gdbarch, |
| 253 | stap_register_indirection_prefixes); |
| 254 | set_gdbarch_stap_register_indirection_suffixes (gdbarch, |
| 255 | stap_register_indirection_suffixes); |
| 256 | set_gdbarch_stap_gdb_register_prefix (gdbarch, "r"); |
| 257 | set_gdbarch_stap_is_single_operand (gdbarch, |
| 258 | ia64_linux_stap_is_single_operand); |
| 259 | } |
| 260 | |
| 261 | void |
| 262 | _initialize_ia64_linux_tdep (void) |
| 263 | { |
| 264 | gdbarch_register_osabi (bfd_arch_ia64, 0, GDB_OSABI_LINUX, |
| 265 | ia64_linux_init_abi); |
| 266 | } |