1 /* DWARF2 EH unwinding support for TILEPro. 2 Copyright (C) 2011-2013 Free Software Foundation, Inc. 3 Contributed by Walter Lee (walt@tilera.com) 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 #ifndef inhibit_libc 27 28 #include <arch/abi.h> 29 #include <signal.h> 30 #include <sys/ucontext.h> 31 #include <linux/unistd.h> 32 33 /* Macro to define a copy of the kernel's __rt_sigreturn function 34 (in arch/tile/kernel/entry.S). If that function is changed, 35 this one needs to be changed to match it. */ 36 #define _sigreturn_asm(REG, NR) asm( \ 37 ".pushsection .text.__rt_sigreturn,\"a\"\n" \ 38 ".global __rt_sigreturn\n" \ 39 ".type __rt_sigreturn,@function\n" \ 40 "__rt_sigreturn:\n" \ 41 "moveli " #REG ", " #NR "\n" \ 42 "swint1\n" \ 43 ".size __rt_sigreturn, . - __rt_sigreturn\n" \ 44 ".popsection") 45 #define sigreturn_asm(REG, NR) _sigreturn_asm(REG, NR) 46 sigreturn_asm (TREG_SYSCALL_NR_NAME, __NR_rt_sigreturn); 47 #define SIGRETURN_LEN 16 48 extern char __rt_sigreturn[]; 49 50 #define MD_FALLBACK_FRAME_STATE_FOR tile_fallback_frame_state 51 52 static _Unwind_Reason_Code 53 tile_fallback_frame_state (struct _Unwind_Context *context, 54 _Unwind_FrameState *fs) 55 { 56 unsigned char *pc = context->ra; 57 struct sigcontext *sc; 58 long new_cfa; 59 int i; 60 61 struct rt_sigframe { 62 unsigned char save_area[C_ABI_SAVE_AREA_SIZE]; 63 siginfo_t info; 64 struct ucontext uc; 65 } *rt_; 66 67 /* Return if this is not a signal handler. */ 68 if (memcmp (pc, __rt_sigreturn, SIGRETURN_LEN) != 0) 69 return _URC_END_OF_STACK; 70 71 /* It was a signal handler; update the reported PC to point to our 72 copy, since that will be findable with dladdr() and therefore 73 somewhat easier to help understand what actually happened. */ 74 context->ra = __rt_sigreturn; 75 76 rt_ = context->cfa; 77 sc = &rt_->uc.uc_mcontext; 78 79 new_cfa = sc->sp; 80 fs->regs.cfa_how = CFA_REG_OFFSET; 81 fs->regs.cfa_reg = STACK_POINTER_REGNUM; 82 fs->regs.cfa_offset = new_cfa - (long) context->cfa; 83 84 for (i = 0; i < 56; ++i) 85 { 86 fs->regs.reg[i].how = REG_SAVED_OFFSET; 87 fs->regs.reg[i].loc.offset 88 = (long)&sc->gregs[i] - new_cfa; 89 } 90 91 fs->regs.reg[56].how = REG_SAVED_OFFSET; 92 fs->regs.reg[56].loc.offset = (long)&sc->pc - new_cfa; 93 fs->retaddr_column = 56; 94 fs->signal_frame = 1; 95 96 return _URC_NO_REASON; 97 } 98 99 #endif /* ifdef inhibit_libc */ 100