/* DWARF2 EH unwinding support for Alpha Linux. Copyright (C) 2004-2017 Free Software Foundation, Inc. This file is part of GCC. GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version. GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. Under Section 7 of GPL version 3, you are granted additional permissions described in the GCC Runtime Library Exception, version 3.1, as published by the Free Software Foundation. You should have received a copy of the GNU General Public License and a copy of the GCC Runtime Library Exception along with this program; see the files COPYING3 and COPYING.RUNTIME respectively. If not, see <http://www.gnu.org/licenses/>. */ #ifndef inhibit_libc /* Do code reading to identify a signal frame, and set the frame state data appropriately. See unwind-dw2.c for the structs. */ #include <signal.h> #include <sys/ucontext.h> #define MD_FALLBACK_FRAME_STATE_FOR alpha_fallback_frame_state static _Unwind_Reason_Code alpha_fallback_frame_state (struct _Unwind_Context *context, _Unwind_FrameState *fs) { unsigned int *pc = context->ra; struct sigcontext *sc; long new_cfa; int i; if (pc[0] != 0x47fe0410 /* mov $30,$16 */ || pc[2] != 0x00000083) /* callsys */ return _URC_END_OF_STACK; if (context->cfa == 0) return _URC_END_OF_STACK; if (pc[1] == 0x201f0067) /* lda $0,NR_sigreturn */ sc = context->cfa; else if (pc[1] == 0x201f015f) /* lda $0,NR_rt_sigreturn */ { struct rt_sigframe { siginfo_t info; ucontext_t uc; } *rt_ = context->cfa; sc = &rt_->uc.uc_mcontext; } else return _URC_END_OF_STACK; new_cfa = sc->sc_regs[30]; fs->regs.cfa_how = CFA_REG_OFFSET; fs->regs.cfa_reg = 30; fs->regs.cfa_offset = new_cfa - (long) context->cfa; for (i = 0; i < 30; ++i) { fs->regs.reg[i].how = REG_SAVED_OFFSET; fs->regs.reg[i].loc.offset = (long) &sc->sc_regs[i] - new_cfa; } for (i = 0; i < 31; ++i) { fs->regs.reg[i+32].how = REG_SAVED_OFFSET; fs->regs.reg[i+32].loc.offset = (long) &sc->sc_fpregs[i] - new_cfa; } fs->regs.reg[64].how = REG_SAVED_OFFSET; fs->regs.reg[64].loc.offset = (long)&sc->sc_pc - new_cfa; fs->retaddr_column = 64; fs->signal_frame = 1; return _URC_NO_REASON; } #define MD_FROB_UPDATE_CONTEXT alpha_frob_update_context /* Fix up for signal handlers that don't have S flag set. */ static void alpha_frob_update_context (struct _Unwind_Context *context, _Unwind_FrameState *fs ATTRIBUTE_UNUSED) { unsigned int *pc = context->ra; if (pc[0] == 0x47fe0410 /* mov $30,$16 */ && pc[2] == 0x00000083 /* callsys */ && (pc[1] == 0x201f0067 /* lda $0,NR_sigreturn */ || pc[1] == 0x201f015f)) /* lda $0,NR_rt_sigreturn */ _Unwind_SetSignalFrame (context, 1); } #endif