1 /* DWARF2 EH unwinding support for DragonFly BSD: AMD x86-64 and x86. 2 Copyright (C) 2014-2024 Free Software Foundation, Inc. 3 Contributed by John Marino <gnugcc (at) marino.st> 4 5 This file is part of GCC. 6 7 GCC 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, or (at your option) 10 any later version. 11 12 GCC 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 Under Section 7 of GPL version 3, you are granted additional 18 permissions described in the GCC Runtime Library Exception, version 19 3.1, as published by the Free Software Foundation. 20 21 You should have received a copy of the GNU General Public License and 22 a copy of the GCC Runtime Library Exception along with this program; 23 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24 <http://www.gnu.org/licenses/>. */ 25 26 /* Do code reading to identify a signal frame, and set the frame 27 state data appropriately. See unwind-dw2.c for the structs. */ 28 29 #include <sys/types.h> 30 #include <sys/sysctl.h> 31 #include <sys/param.h> 32 #include <signal.h> 33 #include <sys/ucontext.h> 34 #include <machine/sigframe.h> 35 #if __DragonFly_version > 400800 36 #include <sys/kinfo.h> 37 #endif 38 39 40 #define REG_NAME(reg) sf_uc.uc_mcontext.mc_## reg 41 42 #ifdef __x86_64__ 43 #define MD_FALLBACK_FRAME_STATE_FOR x86_64_dragonfly_fallback_frame_state 44 45 46 static int 47 x86_64_outside_sigtramp_range (unsigned char *pc) 48 { 49 static int sigtramp_range_determined = 0; 50 static unsigned char *sigtramp_start, *sigtramp_end; 51 52 if (sigtramp_range_determined == 0) 53 { 54 #if __DragonFly_version > 400800 55 struct kinfo_sigtramp kst = {0}; 56 size_t len = sizeof (kst); 57 int mib[3] = { CTL_KERN, KERN_PROC, KERN_PROC_SIGTRAMP }; 58 59 sigtramp_range_determined = 1; 60 if (sysctl (mib, 3, &kst, &len, NULL, 0) == 0) 61 { 62 sigtramp_range_determined = 2; 63 sigtramp_start = kst.ksigtramp_start; 64 sigtramp_end = kst.ksigtramp_end; 65 } 66 #else 67 unsigned long ps_strings; 68 size_t len = sizeof (ps_strings); 69 int mib[2] = { CTL_KERN, KERN_PS_STRINGS }; 70 71 sigtramp_range_determined = 1; 72 if (sysctl (mib, 2, &ps_strings, &len, NULL, 0) == 0) 73 { 74 sigtramp_range_determined = 2; 75 sigtramp_start = (unsigned char *)ps_strings - 32; 76 sigtramp_end = (unsigned char *)ps_strings; 77 } 78 #endif 79 } 80 if (sigtramp_range_determined < 2) /* sysctl failed if < 2 */ 81 return 1; 82 83 return (pc < sigtramp_start || pc >= sigtramp_end ); 84 } 85 86 87 static _Unwind_Reason_Code 88 x86_64_dragonfly_fallback_frame_state 89 (struct _Unwind_Context *context, _Unwind_FrameState *fs) 90 { 91 struct sigframe *sf; 92 long new_cfa; 93 94 if (x86_64_outside_sigtramp_range(context->ra)) 95 return _URC_END_OF_STACK; 96 97 sf = (struct sigframe *) context->cfa; 98 new_cfa = sf->REG_NAME(rsp); 99 fs->regs.cfa_how = CFA_REG_OFFSET; 100 /* Register 7 is rsp */ 101 fs->regs.cfa_reg = 7; 102 fs->regs.cfa_offset = new_cfa - (long) context->cfa; 103 104 /* The SVR4 register numbering macros aren't usable in libgcc. */ 105 fs->regs.how[0] = REG_SAVED_OFFSET; 106 fs->regs.reg[0].loc.offset = (long)&sf->REG_NAME(rax) - new_cfa; 107 fs->regs.how[1] = REG_SAVED_OFFSET; 108 fs->regs.reg[1].loc.offset = (long)&sf->REG_NAME(rdx) - new_cfa; 109 fs->regs.how[2] = REG_SAVED_OFFSET; 110 fs->regs.reg[2].loc.offset = (long)&sf->REG_NAME(rcx) - new_cfa; 111 fs->regs.how[3] = REG_SAVED_OFFSET; 112 fs->regs.reg[3].loc.offset = (long)&sf->REG_NAME(rbx) - new_cfa; 113 fs->regs.how[4] = REG_SAVED_OFFSET; 114 fs->regs.reg[4].loc.offset = (long)&sf->REG_NAME(rsi) - new_cfa; 115 fs->regs.how[5] = REG_SAVED_OFFSET; 116 fs->regs.reg[5].loc.offset = (long)&sf->REG_NAME(rdi) - new_cfa; 117 fs->regs.how[6] = REG_SAVED_OFFSET; 118 fs->regs.reg[6].loc.offset = (long)&sf->REG_NAME(rbp) - new_cfa; 119 fs->regs.how[8] = REG_SAVED_OFFSET; 120 fs->regs.reg[8].loc.offset = (long)&sf->REG_NAME(r8) - new_cfa; 121 fs->regs.how[9] = REG_SAVED_OFFSET; 122 fs->regs.reg[9].loc.offset = (long)&sf->REG_NAME(r9) - new_cfa; 123 fs->regs.how[10] = REG_SAVED_OFFSET; 124 fs->regs.reg[10].loc.offset = (long)&sf->REG_NAME(r10) - new_cfa; 125 fs->regs.how[11] = REG_SAVED_OFFSET; 126 fs->regs.reg[11].loc.offset = (long)&sf->REG_NAME(r11) - new_cfa; 127 fs->regs.how[12] = REG_SAVED_OFFSET; 128 fs->regs.reg[12].loc.offset = (long)&sf->REG_NAME(r12) - new_cfa; 129 fs->regs.how[13] = REG_SAVED_OFFSET; 130 fs->regs.reg[13].loc.offset = (long)&sf->REG_NAME(r13) - new_cfa; 131 fs->regs.how[14] = REG_SAVED_OFFSET; 132 fs->regs.reg[14].loc.offset = (long)&sf->REG_NAME(r14) - new_cfa; 133 fs->regs.how[15] = REG_SAVED_OFFSET; 134 fs->regs.reg[15].loc.offset = (long)&sf->REG_NAME(r15) - new_cfa; 135 fs->regs.how[16] = REG_SAVED_OFFSET; 136 fs->regs.reg[16].loc.offset = (long)&sf->REG_NAME(rip) - new_cfa; 137 fs->retaddr_column = 16; 138 fs->signal_frame = 1; 139 return _URC_NO_REASON; 140 } 141 142 #else /* Next section is for i386 */ 143 144 #define MD_FALLBACK_FRAME_STATE_FOR x86_dragonfly_fallback_frame_state 145 146 147 static void 148 x86_sigtramp_range (unsigned char **start, unsigned char **end) 149 { 150 unsigned long ps_strings; 151 int mib[2]; 152 size_t len; 153 154 mib[0] = CTL_KERN; 155 mib[1] = KERN_PS_STRINGS; 156 len = sizeof (ps_strings); 157 sysctl (mib, 2, &ps_strings, &len, NULL, 0); 158 159 *start = (unsigned char *)ps_strings - 128; 160 *end = (unsigned char *)ps_strings; 161 } 162 163 164 static _Unwind_Reason_Code 165 x86_dragonfly_fallback_frame_state 166 (struct _Unwind_Context *context, _Unwind_FrameState *fs) 167 { 168 unsigned char *pc = context->ra; 169 unsigned char *sigtramp_start, *sigtramp_end; 170 struct sigframe *sf; 171 long new_cfa; 172 173 x86_sigtramp_range(&sigtramp_start, &sigtramp_end); 174 175 if (pc >= sigtramp_end || pc < sigtramp_start) 176 return _URC_END_OF_STACK; 177 178 sf = (struct sigframe *) context->cfa; 179 new_cfa = sf->REG_NAME(esp); 180 fs->regs.cfa_how = CFA_REG_OFFSET; 181 fs->regs.cfa_reg = 4; 182 fs->regs.cfa_offset = new_cfa - (long) context->cfa; 183 184 /* The SVR4 register numbering macros aren't usable in libgcc. */ 185 fs->regs.how[0] = REG_SAVED_OFFSET; 186 fs->regs.reg[0].loc.offset = (long)&sf->REG_NAME(eax) - new_cfa; 187 fs->regs.how[3] = REG_SAVED_OFFSET; 188 fs->regs.reg[3].loc.offset = (long)&sf->REG_NAME(ebx) - new_cfa; 189 fs->regs.how[1] = REG_SAVED_OFFSET; 190 fs->regs.reg[1].loc.offset = (long)&sf->REG_NAME(ecx) - new_cfa; 191 fs->regs.how[2] = REG_SAVED_OFFSET; 192 fs->regs.reg[2].loc.offset = (long)&sf->REG_NAME(edx) - new_cfa; 193 fs->regs.how[6] = REG_SAVED_OFFSET; 194 fs->regs.reg[6].loc.offset = (long)&sf->REG_NAME(esi) - new_cfa; 195 fs->regs.how[7] = REG_SAVED_OFFSET; 196 fs->regs.reg[7].loc.offset = (long)&sf->REG_NAME(edi) - new_cfa; 197 fs->regs.how[5] = REG_SAVED_OFFSET; 198 fs->regs.reg[5].loc.offset = (long)&sf->REG_NAME(ebp) - new_cfa; 199 fs->regs.how[8] = REG_SAVED_OFFSET; 200 fs->regs.reg[8].loc.offset = (long)&sf->REG_NAME(eip) - new_cfa; 201 fs->retaddr_column = 8; 202 fs->signal_frame = 1; 203 return _URC_NO_REASON; 204 } 205 #endif /* ifdef __x86_64__ */ 206
Indexes created Sat Feb 28 05:31:39 UTC 2026