1/* DWARF2 EH unwinding support for AMD x86-64 and x86. 2 Copyright (C) 2004, 2005, 2006 Free Software Foundation, Inc. 3 4This file is part of GCC. 5 6GCC is free software; you can redistribute it and/or modify 7it under the terms of the GNU General Public License as published by 8the Free Software Foundation; either version 2, or (at your option) 9any later version. 10 11In addition to the permissions in the GNU General Public License, the 12Free Software Foundation gives you unlimited permission to link the 13compiled version of this file with other programs, and to distribute 14those programs without any restriction coming from the use of this 15file. (The General Public License restrictions do apply in other 16respects; for example, they cover modification of the file, and 17distribution when not linked into another program.) 18 19GCC is distributed in the hope that it will be useful, 20but WITHOUT ANY WARRANTY; without even the implied warranty of 21MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 22GNU General Public License for more details. 23 24You should have received a copy of the GNU General Public License 25along with GCC; see the file COPYING. If not, write to 26the Free Software Foundation, 51 Franklin Street, Fifth Floor, 27Boston, MA 02110-1301, USA. */ 28 29/* Do code reading to identify a signal frame, and set the frame 30 state data appropriately. See unwind-dw2.c for the structs. 31 Don't use this at all if inhibit_libc is used. */ 32 33#ifndef inhibit_libc 34 35#ifdef __x86_64__ 36 37#include <signal.h> 38#include <sys/ucontext.h> 39 40#define MD_FALLBACK_FRAME_STATE_FOR x86_64_fallback_frame_state 41 42static _Unwind_Reason_Code 43x86_64_fallback_frame_state (struct _Unwind_Context *context, 44 _Unwind_FrameState *fs) 45{ 46 unsigned char *pc = context->ra; 47 struct sigcontext *sc; 48 long new_cfa; 49 50 /* movq __NR_rt_sigreturn, %rax ; syscall */ 51 if (*(unsigned char *)(pc+0) == 0x48 52 && *(unsigned long *)(pc+1) == 0x050f0000000fc0c7) 53 { 54 struct ucontext *uc_ = context->cfa; 55 /* The void * cast is necessary to avoid an aliasing warning. 56 The aliasing warning is correct, but should not be a problem 57 because it does not alias anything. */ 58 sc = (struct sigcontext *) (void *) &uc_->uc_mcontext; 59 } 60 else 61 return _URC_END_OF_STACK; 62 63 new_cfa = sc->rsp; 64 fs->cfa_how = CFA_REG_OFFSET; 65 /* Register 7 is rsp */ 66 fs->cfa_reg = 7; 67 fs->cfa_offset = new_cfa - (long) context->cfa; 68 69 /* The SVR4 register numbering macros aren't usable in libgcc. */ 70 fs->regs.reg[0].how = REG_SAVED_OFFSET; 71 fs->regs.reg[0].loc.offset = (long)&sc->rax - new_cfa; 72 fs->regs.reg[1].how = REG_SAVED_OFFSET; 73 fs->regs.reg[1].loc.offset = (long)&sc->rdx - new_cfa; 74 fs->regs.reg[2].how = REG_SAVED_OFFSET; 75 fs->regs.reg[2].loc.offset = (long)&sc->rcx - new_cfa; 76 fs->regs.reg[3].how = REG_SAVED_OFFSET; 77 fs->regs.reg[3].loc.offset = (long)&sc->rbx - new_cfa; 78 fs->regs.reg[4].how = REG_SAVED_OFFSET; 79 fs->regs.reg[4].loc.offset = (long)&sc->rsi - new_cfa; 80 fs->regs.reg[5].how = REG_SAVED_OFFSET; 81 fs->regs.reg[5].loc.offset = (long)&sc->rdi - new_cfa; 82 fs->regs.reg[6].how = REG_SAVED_OFFSET; 83 fs->regs.reg[6].loc.offset = (long)&sc->rbp - new_cfa; 84 fs->regs.reg[8].how = REG_SAVED_OFFSET; 85 fs->regs.reg[8].loc.offset = (long)&sc->r8 - new_cfa; 86 fs->regs.reg[9].how = REG_SAVED_OFFSET; 87 fs->regs.reg[9].loc.offset = (long)&sc->r9 - new_cfa; 88 fs->regs.reg[10].how = REG_SAVED_OFFSET; 89 fs->regs.reg[10].loc.offset = (long)&sc->r10 - new_cfa; 90 fs->regs.reg[11].how = REG_SAVED_OFFSET; 91 fs->regs.reg[11].loc.offset = (long)&sc->r11 - new_cfa; 92 fs->regs.reg[12].how = REG_SAVED_OFFSET; 93 fs->regs.reg[12].loc.offset = (long)&sc->r12 - new_cfa; 94 fs->regs.reg[13].how = REG_SAVED_OFFSET; 95 fs->regs.reg[13].loc.offset = (long)&sc->r13 - new_cfa; 96 fs->regs.reg[14].how = REG_SAVED_OFFSET; 97 fs->regs.reg[14].loc.offset = (long)&sc->r14 - new_cfa; 98 fs->regs.reg[15].how = REG_SAVED_OFFSET; 99 fs->regs.reg[15].loc.offset = (long)&sc->r15 - new_cfa; 100 fs->regs.reg[16].how = REG_SAVED_OFFSET; 101 fs->regs.reg[16].loc.offset = (long)&sc->rip - new_cfa; 102 fs->retaddr_column = 16; 103 fs->signal_frame = 1; 104 return _URC_NO_REASON; 105} 106 107#else /* ifdef __x86_64__ */ 108 109/* There's no sys/ucontext.h for glibc 2.0, so no 110 signal-turned-exceptions for them. There's also no configure-run for 111 the target, so we can't check on (e.g.) HAVE_SYS_UCONTEXT_H. Using the 112 target libc version macro should be enough. */ 113#if !(__GLIBC__ == 2 && __GLIBC_MINOR__ == 0) 114 115#include <signal.h> 116#include <sys/ucontext.h> 117 118#define MD_FALLBACK_FRAME_STATE_FOR x86_fallback_frame_state 119 120static _Unwind_Reason_Code 121x86_fallback_frame_state (struct _Unwind_Context *context, 122 _Unwind_FrameState *fs) 123{ 124 unsigned char *pc = context->ra; 125 struct sigcontext *sc; 126 long new_cfa; 127 128 /* popl %eax ; movl $__NR_sigreturn,%eax ; int $0x80 */ 129 if (*(unsigned short *)(pc+0) == 0xb858 130 && *(unsigned int *)(pc+2) == 119 131 && *(unsigned short *)(pc+6) == 0x80cd) 132 sc = context->cfa + 4; 133 /* movl $__NR_rt_sigreturn,%eax ; int $0x80 */ 134 else if (*(unsigned char *)(pc+0) == 0xb8 135 && *(unsigned int *)(pc+1) == 173 136 && *(unsigned short *)(pc+5) == 0x80cd) 137 { 138 struct rt_sigframe { 139 int sig; 140 struct siginfo *pinfo; 141 void *puc; 142 struct siginfo info; 143 struct ucontext uc; 144 } *rt_ = context->cfa; 145 /* The void * cast is necessary to avoid an aliasing warning. 146 The aliasing warning is correct, but should not be a problem 147 because it does not alias anything. */ 148 sc = (struct sigcontext *) (void *) &rt_->uc.uc_mcontext; 149 } 150 else 151 return _URC_END_OF_STACK; 152 153 new_cfa = sc->REG_NAME(esp); 154 fs->cfa_how = CFA_REG_OFFSET; 155 fs->cfa_reg = 4; 156 fs->cfa_offset = new_cfa - (long) context->cfa; 157 158 /* The SVR4 register numbering macros aren't usable in libgcc. */ 159 fs->regs.reg[0].how = REG_SAVED_OFFSET; 160 fs->regs.reg[0].loc.offset = (long)&sc->REG_NAME(eax) - new_cfa; 161 fs->regs.reg[3].how = REG_SAVED_OFFSET; 162 fs->regs.reg[3].loc.offset = (long)&sc->REG_NAME(ebx) - new_cfa; 163 fs->regs.reg[1].how = REG_SAVED_OFFSET; 164 fs->regs.reg[1].loc.offset = (long)&sc->REG_NAME(ecx) - new_cfa; 165 fs->regs.reg[2].how = REG_SAVED_OFFSET; 166 fs->regs.reg[2].loc.offset = (long)&sc->REG_NAME(edx) - new_cfa; 167 fs->regs.reg[6].how = REG_SAVED_OFFSET; 168 fs->regs.reg[6].loc.offset = (long)&sc->REG_NAME(esi) - new_cfa; 169 fs->regs.reg[7].how = REG_SAVED_OFFSET; 170 fs->regs.reg[7].loc.offset = (long)&sc->REG_NAME(edi) - new_cfa; 171 fs->regs.reg[5].how = REG_SAVED_OFFSET; 172 fs->regs.reg[5].loc.offset = (long)&sc->REG_NAME(ebp) - new_cfa; 173 fs->regs.reg[8].how = REG_SAVED_OFFSET; 174 fs->regs.reg[8].loc.offset = (long)&sc->REG_NAME(eip) - new_cfa; 175 fs->retaddr_column = 8; 176 fs->signal_frame = 1; 177 return _URC_NO_REASON; 178} 179#endif /* not glibc 2.0 */ 180#endif /* ifdef __x86_64__ */ 181#endif /* ifdef inhibit_libc */ 182