1/* DWARF2 EH unwinding support for Alpha Linux. 2 Copyright (C) 2004, 2005, 2009 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 3, or (at your option) 9any later version. 10 11GCC is distributed in the hope that it will be useful, 12but WITHOUT ANY WARRANTY; without even the implied warranty of 13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14GNU General Public License for more details. 15 16Under Section 7 of GPL version 3, you are granted additional 17permissions described in the GCC Runtime Library Exception, version 183.1, as published by the Free Software Foundation. 19 20You should have received a copy of the GNU General Public License and 21a copy of the GCC Runtime Library Exception along with this program; 22see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23<http://www.gnu.org/licenses/>. */ 24 25/* Do code reading to identify a signal frame, and set the frame 26 state data appropriately. See unwind-dw2.c for the structs. */ 27 28#include <signal.h> 29#include <sys/ucontext.h> 30 31#define MD_FALLBACK_FRAME_STATE_FOR alpha_fallback_frame_state 32 33static _Unwind_Reason_Code 34alpha_fallback_frame_state (struct _Unwind_Context *context, 35 _Unwind_FrameState *fs) 36{ 37 unsigned int *pc = context->ra; 38 struct sigcontext *sc; 39 long new_cfa, i; 40 41 if (pc[0] != 0x47fe0410 /* mov $30,$16 */ 42 || pc[2] != 0x00000083 /* callsys */) 43 return _URC_END_OF_STACK; 44 if (context->cfa == 0) 45 return _URC_END_OF_STACK; 46 if (pc[1] == 0x201f0067) /* lda $0,NR_sigreturn */ 47 sc = context->cfa; 48 else if (pc[1] == 0x201f015f) /* lda $0,NR_rt_sigreturn */ 49 { 50 struct rt_sigframe { 51 struct siginfo info; 52 struct ucontext uc; 53 } *rt_ = context->cfa; 54 sc = &rt_->uc.uc_mcontext; 55 } 56 else 57 return _URC_END_OF_STACK; 58 new_cfa = sc->sc_regs[30]; 59 fs->regs.cfa_how = CFA_REG_OFFSET; 60 fs->regs.cfa_reg = 30; 61 fs->regs.cfa_offset = new_cfa - (long) context->cfa; 62 for (i = 0; i < 30; ++i) 63 { 64 fs->regs.reg[i].how = REG_SAVED_OFFSET; 65 fs->regs.reg[i].loc.offset 66 = (long)&sc->sc_regs[i] - new_cfa; 67 } 68 for (i = 0; i < 31; ++i) 69 { 70 fs->regs.reg[i+32].how = REG_SAVED_OFFSET; 71 fs->regs.reg[i+32].loc.offset 72 = (long)&sc->sc_fpregs[i] - new_cfa; 73 } 74 fs->regs.reg[64].how = REG_SAVED_OFFSET; 75 fs->regs.reg[64].loc.offset = (long)&sc->sc_pc - new_cfa; 76 fs->retaddr_column = 64; 77 return _URC_NO_REASON; 78} 79