1 /* Target-dependent code for OpenBSD/mips64. 2 3 Copyright (C) 2004-2019 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 "gdbtypes.h" 22 #include "osabi.h" 23 #include "regcache.h" 24 #include "regset.h" 25 #include "trad-frame.h" 26 #include "tramp-frame.h" 27 28 #include "obsd-tdep.h" 29 #include "mips-tdep.h" 30 #include "solib-svr4.h" 31 32 /* The MIPS64 Floating-Point Quad-Precision format is similar to 33 big-endian IA-64 Quad-Precision format. */ 34 #define floatformats_mips64_quad floatformats_ia64_quad 35 36 #define MIPS64OBSD_NUM_REGS 73 37 38 /* Core file support. */ 39 40 /* Supply register REGNUM from the buffer specified by GREGS and LEN 41 in the general-purpose register set REGSET to register cache 42 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */ 43 44 static void 45 mips64obsd_supply_gregset (const struct regset *regset, 46 struct regcache *regcache, int regnum, 47 const void *gregs, size_t len) 48 { 49 const char *regs = (const char *) gregs; 50 int i; 51 52 for (i = 0; i < MIPS64OBSD_NUM_REGS; i++) 53 { 54 if (regnum == i || regnum == -1) 55 regcache->raw_supply (i, regs + i * 8); 56 } 57 } 58 59 /* OpenBSD/mips64 register set. */ 60 61 static const struct regset mips64obsd_gregset = 62 { 63 NULL, 64 mips64obsd_supply_gregset 65 }; 66 67 /* Iterate over core file register note sections. */ 68 69 static void 70 mips64obsd_iterate_over_regset_sections (struct gdbarch *gdbarch, 71 iterate_over_regset_sections_cb *cb, 72 void *cb_data, 73 const struct regcache *regcache) 74 { 75 cb (".reg", MIPS64OBSD_NUM_REGS * 8, MIPS64OBSD_NUM_REGS * 8, 76 &mips64obsd_gregset, NULL, cb_data); 77 } 78 79 80 /* Signal trampolines. */ 81 82 static void 83 mips64obsd_sigframe_init (const struct tramp_frame *self, 84 struct frame_info *this_frame, 85 struct trad_frame_cache *cache, 86 CORE_ADDR func) 87 { 88 struct gdbarch *gdbarch = get_frame_arch (this_frame); 89 CORE_ADDR sp, sigcontext_addr, addr; 90 int regnum; 91 92 /* We find the appropriate instance of `struct sigcontext' at a 93 fixed offset in the signal frame. */ 94 sp = get_frame_register_signed (this_frame, 95 MIPS_SP_REGNUM + gdbarch_num_regs (gdbarch)); 96 sigcontext_addr = sp + 32; 97 98 /* PC. */ 99 regnum = mips_regnum (gdbarch)->pc; 100 trad_frame_set_reg_addr (cache, 101 regnum + gdbarch_num_regs (gdbarch), 102 sigcontext_addr + 16); 103 104 /* GPRs. */ 105 for (regnum = MIPS_AT_REGNUM, addr = sigcontext_addr + 32; 106 regnum <= MIPS_RA_REGNUM; regnum++, addr += 8) 107 trad_frame_set_reg_addr (cache, 108 regnum + gdbarch_num_regs (gdbarch), 109 addr); 110 111 /* HI and LO. */ 112 regnum = mips_regnum (gdbarch)->lo; 113 trad_frame_set_reg_addr (cache, 114 regnum + gdbarch_num_regs (gdbarch), 115 sigcontext_addr + 280); 116 regnum = mips_regnum (gdbarch)->hi; 117 trad_frame_set_reg_addr (cache, 118 regnum + gdbarch_num_regs (gdbarch), 119 sigcontext_addr + 288); 120 121 /* TODO: Handle the floating-point registers. */ 122 123 trad_frame_set_id (cache, frame_id_build (sp, func)); 124 } 125 126 static const struct tramp_frame mips64obsd_sigframe = 127 { 128 SIGTRAMP_FRAME, 129 MIPS_INSN32_SIZE, 130 { 131 { 0x67a40020, ULONGEST_MAX }, /* daddiu a0,sp,32 */ 132 { 0x24020067, ULONGEST_MAX }, /* li v0,103 */ 133 { 0x0000000c, ULONGEST_MAX }, /* syscall */ 134 { 0x0000000d, ULONGEST_MAX }, /* break */ 135 { TRAMP_SENTINEL_INSN, ULONGEST_MAX } 136 }, 137 mips64obsd_sigframe_init 138 }; 139 140 141 static void 142 mips64obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) 143 { 144 /* OpenBSD/mips64 only supports the n64 ABI, but the braindamaged 145 way GDB works, forces us to pretend we can handle them all. */ 146 147 set_gdbarch_iterate_over_regset_sections 148 (gdbarch, mips64obsd_iterate_over_regset_sections); 149 150 tramp_frame_prepend_unwinder (gdbarch, &mips64obsd_sigframe); 151 152 set_gdbarch_long_double_bit (gdbarch, 128); 153 set_gdbarch_long_double_format (gdbarch, floatformats_mips64_quad); 154 155 obsd_init_abi(info, gdbarch); 156 157 /* OpenBSD/mips64 has SVR4-style shared libraries. */ 158 set_solib_svr4_fetch_link_map_offsets 159 (gdbarch, svr4_lp64_fetch_link_map_offsets); 160 } 161 162 void 163 _initialize_mips64obsd_tdep (void) 164 { 165 gdbarch_register_osabi (bfd_arch_mips, 0, GDB_OSABI_OPENBSD, 166 mips64obsd_init_abi); 167 } 168