libgcc/config/i386/dragonfly-unwind.h

   1 /* DWARF2 EH unwinding support for DragonFly BSD: AMD x86-64 and x86.
   2    Copyright (C) 2014-2016 Free Software Foundation, Inc.
   3    Contributed by John Marino <gnugcc@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 <signal.h>
  32 #include <sys/ucontext.h>
  33 #include <machine/sigframe.h>
  34
  35
  36 #define REG_NAME(reg)   sf_uc.uc_mcontext.mc_## reg
  37
  38 #ifdef __x86_64__
  39 #define MD_FALLBACK_FRAME_STATE_FOR x86_64_dragonfly_fallback_frame_state
  40
  41
  42 static void
  43 x86_64_sigtramp_range (unsigned char **start, unsigned char **end)
  44 {
  45   unsigned long ps_strings;
  46   int mib[2];
  47   size_t len;
  48
  49   mib[0] = CTL_KERN;
  50   mib[1] = KERN_PS_STRINGS;
  51   len = sizeof (ps_strings);
  52   sysctl (mib, 2, &ps_strings, &len, NULL, 0);
  53
  54   *start = (unsigned char *)ps_strings - 32;
  55   *end   = (unsigned char *)ps_strings;
  56 }
  57
  58
  59 static _Unwind_Reason_Code
  60 x86_64_dragonfly_fallback_frame_state
  61 (struct _Unwind_Context *context, _Unwind_FrameState *fs)
  62 {
  63   unsigned char *pc = context->ra;
  64   unsigned char *sigtramp_start, *sigtramp_end;
  65   struct sigframe *sf;
  66   long new_cfa;
  67
  68   x86_64_sigtramp_range(&sigtramp_start, &sigtramp_end);
  69   if (pc >= sigtramp_end || pc < sigtramp_start)
  70     return _URC_END_OF_STACK;
  71
  72   sf = (struct sigframe *) context->cfa;
  73   new_cfa = sf->REG_NAME(rsp);
  74   fs->regs.cfa_how = CFA_REG_OFFSET;
  75   /* Register 7 is rsp  */
  76   fs->regs.cfa_reg = 7;
  77   fs->regs.cfa_offset = new_cfa - (long) context->cfa;
  78
  79   /* The SVR4 register numbering macros aren't usable in libgcc.  */
  80   fs->regs.reg[0].how = REG_SAVED_OFFSET;
  81   fs->regs.reg[0].loc.offset = (long)&sf->REG_NAME(rax) - new_cfa;
  82   fs->regs.reg[1].how = REG_SAVED_OFFSET;
  83   fs->regs.reg[1].loc.offset = (long)&sf->REG_NAME(rdx) - new_cfa;
  84   fs->regs.reg[2].how = REG_SAVED_OFFSET;
  85   fs->regs.reg[2].loc.offset = (long)&sf->REG_NAME(rcx) - new_cfa;
  86   fs->regs.reg[3].how = REG_SAVED_OFFSET;
  87   fs->regs.reg[3].loc.offset = (long)&sf->REG_NAME(rbx) - new_cfa;
  88   fs->regs.reg[4].how = REG_SAVED_OFFSET;
  89   fs->regs.reg[4].loc.offset = (long)&sf->REG_NAME(rsi) - new_cfa;
  90   fs->regs.reg[5].how = REG_SAVED_OFFSET;
  91   fs->regs.reg[5].loc.offset = (long)&sf->REG_NAME(rdi) - new_cfa;
  92   fs->regs.reg[6].how = REG_SAVED_OFFSET;
  93   fs->regs.reg[6].loc.offset = (long)&sf->REG_NAME(rbp) - new_cfa;
  94   fs->regs.reg[8].how = REG_SAVED_OFFSET;
  95   fs->regs.reg[8].loc.offset = (long)&sf->REG_NAME(r8) - new_cfa;
  96   fs->regs.reg[9].how = REG_SAVED_OFFSET;
  97   fs->regs.reg[9].loc.offset = (long)&sf->REG_NAME(r9) - new_cfa;
  98   fs->regs.reg[10].how = REG_SAVED_OFFSET;
  99   fs->regs.reg[10].loc.offset = (long)&sf->REG_NAME(r10) - new_cfa;
 100   fs->regs.reg[11].how = REG_SAVED_OFFSET;
 101   fs->regs.reg[11].loc.offset = (long)&sf->REG_NAME(r11) - new_cfa;
 102   fs->regs.reg[12].how = REG_SAVED_OFFSET;
 103   fs->regs.reg[12].loc.offset = (long)&sf->REG_NAME(r12) - new_cfa;
 104   fs->regs.reg[13].how = REG_SAVED_OFFSET;
 105   fs->regs.reg[13].loc.offset = (long)&sf->REG_NAME(r13) - new_cfa;
 106   fs->regs.reg[14].how = REG_SAVED_OFFSET;
 107   fs->regs.reg[14].loc.offset = (long)&sf->REG_NAME(r14) - new_cfa;
 108   fs->regs.reg[15].how = REG_SAVED_OFFSET;
 109   fs->regs.reg[15].loc.offset = (long)&sf->REG_NAME(r15) - new_cfa;
 110   fs->regs.reg[16].how = REG_SAVED_OFFSET;
 111   fs->regs.reg[16].loc.offset = (long)&sf->REG_NAME(rip) - new_cfa;
 112   fs->retaddr_column = 16;
 113   fs->signal_frame = 1;
 114   return _URC_NO_REASON;
 115 }
 116
 117 #else /* Next section is for i386  */
 118
 119 #define MD_FALLBACK_FRAME_STATE_FOR x86_dragonfly_fallback_frame_state
 120
 121
 122 static void
 123 x86_sigtramp_range (unsigned char **start, unsigned char **end)
 124 {
 125   unsigned long ps_strings;
 126   int mib[2];
 127   size_t len;
 128
 129   mib[0] = CTL_KERN;
 130   mib[1] = KERN_PS_STRINGS;
 131   len = sizeof (ps_strings);
 132   sysctl (mib, 2, &ps_strings, &len, NULL, 0);
 133
 134   *start = (unsigned char *)ps_strings - 128;
 135   *end   = (unsigned char *)ps_strings;
 136 }
 137
 138
 139 static _Unwind_Reason_Code
 140 x86_dragonfly_fallback_frame_state
 141 (struct _Unwind_Context *context, _Unwind_FrameState *fs)
 142 {
 143   unsigned char *pc = context->ra;
 144   unsigned char *sigtramp_start, *sigtramp_end;
 145   struct sigframe *sf;
 146   long new_cfa;
 147
 148   x86_sigtramp_range(&sigtramp_start, &sigtramp_end);
 149
 150   if (pc >= sigtramp_end || pc < sigtramp_start)
 151     return _URC_END_OF_STACK;
 152
 153   sf = (struct sigframe *) context->cfa;
 154   new_cfa = sf->REG_NAME(esp);
 155   fs->regs.cfa_how = CFA_REG_OFFSET;
 156   fs->regs.cfa_reg = 4;
 157   fs->regs.cfa_offset = new_cfa - (long) context->cfa;
 158
 159   /* The SVR4 register numbering macros aren't usable in libgcc.  */
 160   fs->regs.reg[0].how = REG_SAVED_OFFSET;
 161   fs->regs.reg[0].loc.offset = (long)&sf->REG_NAME(eax) - new_cfa;
 162   fs->regs.reg[3].how = REG_SAVED_OFFSET;
 163   fs->regs.reg[3].loc.offset = (long)&sf->REG_NAME(ebx) - new_cfa;
 164   fs->regs.reg[1].how = REG_SAVED_OFFSET;
 165   fs->regs.reg[1].loc.offset = (long)&sf->REG_NAME(ecx) - new_cfa;
 166   fs->regs.reg[2].how = REG_SAVED_OFFSET;
 167   fs->regs.reg[2].loc.offset = (long)&sf->REG_NAME(edx) - new_cfa;
 168   fs->regs.reg[6].how = REG_SAVED_OFFSET;
 169   fs->regs.reg[6].loc.offset = (long)&sf->REG_NAME(esi) - new_cfa;
 170   fs->regs.reg[7].how = REG_SAVED_OFFSET;
 171   fs->regs.reg[7].loc.offset = (long)&sf->REG_NAME(edi) - new_cfa;
 172   fs->regs.reg[5].how = REG_SAVED_OFFSET;
 173   fs->regs.reg[5].loc.offset = (long)&sf->REG_NAME(ebp) - new_cfa;
 174   fs->regs.reg[8].how = REG_SAVED_OFFSET;
 175   fs->regs.reg[8].loc.offset = (long)&sf->REG_NAME(eip) - new_cfa;
 176   fs->retaddr_column = 8;
 177   fs->signal_frame = 1;
 178   return _URC_NO_REASON;
 179 }
 180 #endif /* ifdef __x86_64__  */