| /* DWARF2 EH unwinding support for FreeBSD/ARM64 (aarch64). |
| Copyright (C) 2017-2019 Free Software Foundation, Inc. |
| Contributed by John Marino <gnugcc@marino.st> |
| |
| 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/>. */ |
| |
| /* Identify a signal frame, and set the frame state data appropriately. |
| See unwind-dw2.c for the structs. */ |
| |
| /* Always include AArch64 unwinder header file. */ |
| #include "config/aarch64/aarch64-unwind.h" |
| |
| #include <sys/types.h> |
| #include <signal.h> |
| #include <unistd.h> |
| #include <sys/ucontext.h> |
| #include <machine/frame.h> |
| #include <sys/user.h> |
| #include <sys/sysctl.h> |
| |
| #define REG_NAME(reg) mc_gpregs.gp_## reg |
| #define XREG(num) mc_gpregs.gp_x[num] |
| #define DARC __LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__ |
| |
| #define MD_FALLBACK_FRAME_STATE_FOR aarch64_freebsd_fallback_frame_state |
| |
| static int |
| aarch64_outside_sigtramp_range (unsigned char *pc) |
| { |
| static int sigtramp_range_determined = 0; |
| static unsigned char *sigtramp_start, *sigtramp_end; |
| |
| if (sigtramp_range_determined == 0) |
| { |
| struct kinfo_sigtramp kst = {0}; |
| size_t len = sizeof (kst); |
| int mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_SIGTRAMP, getpid() }; |
| |
| sigtramp_range_determined = 1; |
| if (sysctl (mib, 4, &kst, &len, NULL, 0) == 0) |
| { |
| sigtramp_range_determined = 2; |
| sigtramp_start = kst.ksigtramp_start; |
| sigtramp_end = kst.ksigtramp_end; |
| } |
| } |
| if (sigtramp_range_determined < 2) /* sysctl failed if < 2 */ |
| return 1; |
| |
| return (pc < sigtramp_start || pc >= sigtramp_end); |
| } |
| |
| static _Unwind_Reason_Code |
| aarch64_freebsd_fallback_frame_state |
| (struct _Unwind_Context *context, _Unwind_FrameState *fs) |
| { |
| int n; |
| struct sigframe *sf; |
| mcontext_t *sc; |
| _Unwind_Ptr new_cfa; |
| |
| if (aarch64_outside_sigtramp_range(context->ra)) |
| return _URC_END_OF_STACK; |
| |
| sf = (struct sigframe *) context->cfa; |
| sc = &sf->sf_uc.uc_mcontext; |
| |
| new_cfa = (_Unwind_Ptr) sc; |
| fs->regs.cfa_how = CFA_REG_OFFSET; |
| fs->regs.cfa_reg = __LIBGCC_STACK_POINTER_REGNUM__; |
| fs->regs.cfa_offset = new_cfa - (_Unwind_Ptr) context->cfa; |
| |
| for (n = 0; n < 32; n++) |
| fs->regs.reg[n].how = REG_SAVED_OFFSET; |
| |
| for (n = 0; n < 30; n++) |
| fs->regs.reg[n].loc.offset = (_Unwind_Ptr) &(sc->XREG(n)) - new_cfa; |
| |
| fs->regs.reg[30].loc.offset = (_Unwind_Ptr) &(sc->REG_NAME(lr)) - new_cfa; |
| fs->regs.reg[31].loc.offset = (_Unwind_Ptr) &(sc->REG_NAME(sp)) - new_cfa; |
| |
| fs->regs.reg[DARC].how = REG_SAVED_OFFSET; |
| fs->regs.reg[DARC].loc.offset = (_Unwind_Ptr) &(sc->REG_NAME(elr)) - new_cfa; |
| |
| fs->retaddr_column = DARC; |
| fs->signal_frame = 1; |
| |
| return _URC_NO_REASON; |
| } |