1 /* DWARF2 EH unwinding support for SH Linux. 2 Copyright (C) 2004-2020 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3, or (at your option) 9 any later version. 10 11 GCC is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 Under Section 7 of GPL version 3, you are granted additional 17 permissions described in the GCC Runtime Library Exception, version 18 3.1, as published by the Free Software Foundation. 19 20 You should have received a copy of the GNU General Public License and 21 a copy of the GCC Runtime Library Exception along with this program; 22 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 <http://www.gnu.org/licenses/>. */ 24 25 26 /* Do code reading to identify a signal frame, and set the frame 27 state data appropriately. See unwind-dw2.c for the structs. 28 Don't use this at all if inhibit_libc is used. */ 29 30 #ifndef inhibit_libc 31 32 #include <signal.h> 33 #include <sys/ucontext.h> 34 #include "insn-constants.h" 35 36 #define SH_DWARF_FRAME_GP0 0 37 #define SH_DWARF_FRAME_FP0 25 38 #define SH_DWARF_FRAME_XD0 87 39 #define SH_DWARF_FRAME_PR 17 40 #define SH_DWARF_FRAME_GBR 18 41 #define SH_DWARF_FRAME_MACH 20 42 #define SH_DWARF_FRAME_MACL 21 43 #define SH_DWARF_FRAME_PC 16 44 #define SH_DWARF_FRAME_SR 22 45 #define SH_DWARF_FRAME_FPUL 23 46 #define SH_DWARF_FRAME_FPSCR 24 47 48 #define MD_FALLBACK_FRAME_STATE_FOR sh_fallback_frame_state 49 50 static _Unwind_Reason_Code 51 sh_fallback_frame_state (struct _Unwind_Context *context, 52 _Unwind_FrameState *fs) 53 { 54 unsigned char *pc = context->ra; 55 struct sigcontext *sc; 56 long new_cfa; 57 int i; 58 #if defined (__SH3E__) || defined (__SH4__) 59 int r; 60 #endif 61 62 /* mov.w 1f,r3; trapa #0x10; 1: .short 0x77 (sigreturn) */ 63 /* mov.w 1f,r3; trapa #0x10; 1: .short 0xad (rt_sigreturn) */ 64 /* Newer kernel uses pad instructions to avoid an SH-4 core bug. */ 65 /* mov.w 1f,r3; trapa #0x10; or r0,r0; or r0,r0; or r0,r0; or r0,r0; 66 or r0,r0; 1: .short 0x77 (sigreturn) */ 67 /* mov.w 1f,r3; trapa #0x10; or r0,r0; or r0,r0; or r0,r0; or r0,r0; 68 or r0,r0; 1: .short 0xad (rt_sigreturn) */ 69 if (((*(unsigned short *) (pc+0) == 0x9300) 70 && (*(unsigned short *) (pc+2) == 0xc310) 71 && (*(unsigned short *) (pc+4) == 0x0077)) 72 || (((*(unsigned short *) (pc+0) == 0x9305) 73 && (*(unsigned short *) (pc+2) == 0xc310) 74 && (*(unsigned short *) (pc+14) == 0x0077)))) 75 sc = context->cfa; 76 else if (((*(unsigned short *) (pc+0) == 0x9300) 77 && (*(unsigned short *) (pc+2) == 0xc310) 78 && (*(unsigned short *) (pc+4) == 0x00ad)) 79 || (((*(unsigned short *) (pc+0) == 0x9305) 80 && (*(unsigned short *) (pc+2) == 0xc310) 81 && (*(unsigned short *) (pc+14) == 0x00ad)))) 82 { 83 struct rt_sigframe { 84 siginfo_t info; 85 ucontext_t uc; 86 } *rt_ = context->cfa; 87 /* The void * cast is necessary to avoid an aliasing warning. 88 The aliasing warning is correct, but should not be a problem 89 because it does not alias anything. */ 90 sc = (struct sigcontext *) (void *) &rt_->uc.uc_mcontext; 91 } 92 else 93 return _URC_END_OF_STACK; 94 95 new_cfa = sc->sc_regs[15]; 96 fs->regs.cfa_how = CFA_REG_OFFSET; 97 fs->regs.cfa_reg = 15; 98 fs->regs.cfa_offset = new_cfa - (long) context->cfa; 99 100 for (i = 0; i < 15; i++) 101 { 102 fs->regs.reg[i].how = REG_SAVED_OFFSET; 103 fs->regs.reg[i].loc.offset 104 = (long)&(sc->sc_regs[i]) - new_cfa; 105 } 106 107 fs->regs.reg[SH_DWARF_FRAME_PR].how = REG_SAVED_OFFSET; 108 fs->regs.reg[SH_DWARF_FRAME_PR].loc.offset 109 = (long)&(sc->sc_pr) - new_cfa; 110 fs->regs.reg[SH_DWARF_FRAME_SR].how = REG_SAVED_OFFSET; 111 fs->regs.reg[SH_DWARF_FRAME_SR].loc.offset 112 = (long)&(sc->sc_sr) - new_cfa; 113 fs->regs.reg[SH_DWARF_FRAME_GBR].how = REG_SAVED_OFFSET; 114 fs->regs.reg[SH_DWARF_FRAME_GBR].loc.offset 115 = (long)&(sc->sc_gbr) - new_cfa; 116 fs->regs.reg[SH_DWARF_FRAME_MACH].how = REG_SAVED_OFFSET; 117 fs->regs.reg[SH_DWARF_FRAME_MACH].loc.offset 118 = (long)&(sc->sc_mach) - new_cfa; 119 fs->regs.reg[SH_DWARF_FRAME_MACL].how = REG_SAVED_OFFSET; 120 fs->regs.reg[SH_DWARF_FRAME_MACL].loc.offset 121 = (long)&(sc->sc_macl) - new_cfa; 122 123 #if defined (__SH3E__) || defined (__SH4__) 124 r = SH_DWARF_FRAME_FP0; 125 for (i = 0; i < 16; i++) 126 { 127 fs->regs.reg[r+i].how = REG_SAVED_OFFSET; 128 fs->regs.reg[r+i].loc.offset 129 = (long)&(sc->sc_fpregs[i]) - new_cfa; 130 } 131 132 r = SH_DWARF_FRAME_XD0; 133 for (i = 0; i < 8; i++) 134 { 135 fs->regs.reg[r+i].how = REG_SAVED_OFFSET; 136 fs->regs.reg[r+i].loc.offset 137 = (long)&(sc->sc_xfpregs[2*i]) - new_cfa; 138 } 139 140 fs->regs.reg[SH_DWARF_FRAME_FPUL].how = REG_SAVED_OFFSET; 141 fs->regs.reg[SH_DWARF_FRAME_FPUL].loc.offset 142 = (long)&(sc->sc_fpul) - new_cfa; 143 fs->regs.reg[SH_DWARF_FRAME_FPSCR].how = REG_SAVED_OFFSET; 144 fs->regs.reg[SH_DWARF_FRAME_FPSCR].loc.offset 145 = (long)&(sc->sc_fpscr) - new_cfa; 146 #endif 147 148 fs->regs.reg[SH_DWARF_FRAME_PC].how = REG_SAVED_OFFSET; 149 fs->regs.reg[SH_DWARF_FRAME_PC].loc.offset 150 = (long)&(sc->sc_pc) - new_cfa; 151 fs->retaddr_column = SH_DWARF_FRAME_PC; 152 fs->signal_frame = 1; 153 return _URC_NO_REASON; 154 } 155 156 #endif /* inhibit_libc */ 157