1 /* libunwind - a platform-independent unwind library 2 Copyright (C) 2002-2003 Hewlett-Packard Co 3 Contributed by David Mosberger-Tang <davidm (at) hpl.hp.com> 4 5 Modified for x86_64 by Max Asbock <masbock (at) us.ibm.com> 6 7 This file is part of libunwind. 8 9 Permission is hereby granted, free of charge, to any person obtaining 10 a copy of this software and associated documentation files (the 11 "Software"), to deal in the Software without restriction, including 12 without limitation the rights to use, copy, modify, merge, publish, 13 distribute, sublicense, and/or sell copies of the Software, and to 14 permit persons to whom the Software is furnished to do so, subject to 15 the following conditions: 16 17 The above copyright notice and this permission notice shall be 18 included in all copies or substantial portions of the Software. 19 20 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 21 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 22 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 23 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 24 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 25 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 26 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ 27 28 #include "unwind_i.h" 29 #include "ucontext_i.h" 30 31 #include <sys/syscall.h> 32 33 HIDDEN void 34 tdep_fetch_frame (struct dwarf_cursor *dw, unw_word_t ip, int need_unwind_info) 35 { 36 struct cursor *c = (struct cursor *) dw; 37 assert(! need_unwind_info || dw->pi_valid); 38 assert(! need_unwind_info || dw->pi.unwind_info); 39 if (dw->pi_valid 40 && dw->pi.unwind_info 41 && ((struct dwarf_cie_info *) dw->pi.unwind_info)->signal_frame) 42 c->sigcontext_format = X86_64_SCF_LINUX_RT_SIGFRAME; 43 else 44 c->sigcontext_format = X86_64_SCF_NONE; 45 46 Debug(5, "fetch frame ip=0x%lx cfa=0x%lx format=%d\n", 47 dw->ip, dw->cfa, c->sigcontext_format); 48 } 49 50 HIDDEN void 51 tdep_cache_frame (struct dwarf_cursor *dw, struct dwarf_reg_state *rs) 52 { 53 struct cursor *c = (struct cursor *) dw; 54 rs->signal_frame = c->sigcontext_format; 55 56 Debug(5, "cache frame ip=0x%lx cfa=0x%lx format=%d\n", 57 dw->ip, dw->cfa, c->sigcontext_format); 58 } 59 60 HIDDEN void 61 tdep_reuse_frame (struct dwarf_cursor *dw, struct dwarf_reg_state *rs) 62 { 63 struct cursor *c = (struct cursor *) dw; 64 c->sigcontext_format = rs->signal_frame; 65 if (c->sigcontext_format == X86_64_SCF_LINUX_RT_SIGFRAME) 66 { 67 c->frame_info.frame_type = UNW_X86_64_FRAME_SIGRETURN; 68 /* Offset from cfa to ucontext_t in signal frame. */ 69 c->frame_info.cfa_reg_offset = 0; 70 c->sigcontext_addr = dw->cfa; 71 } 72 else 73 c->sigcontext_addr = 0; 74 75 Debug(5, "reuse frame ip=0x%lx cfa=0x%lx format=%d addr=0x%lx offset=%+d\n", 76 dw->ip, dw->cfa, c->sigcontext_format, c->sigcontext_addr, 77 (c->sigcontext_format == X86_64_SCF_LINUX_RT_SIGFRAME 78 ? c->frame_info.cfa_reg_offset : 0)); 79 } 80 81 PROTECTED int 82 unw_is_signal_frame (unw_cursor_t *cursor) 83 { 84 struct cursor *c = (struct cursor *) cursor; 85 return c->sigcontext_format != X86_64_SCF_NONE; 86 } 87 88 PROTECTED int 89 unw_handle_signal_frame (unw_cursor_t *cursor) 90 { 91 #if UNW_DEBUG /* To silence compiler warnings */ 92 /* Should not get here because we now use kernel-provided dwarf 93 information for the signal trampoline and dwarf_step() works. 94 Hence unw_step() should never call this function. Maybe 95 restore old non-dwarf signal handling here, but then the 96 gating on unw_is_signal_frame() needs to be removed. */ 97 struct cursor *c = (struct cursor *) cursor; 98 Debug(1, "old format signal frame? format=%d addr=0x%lx cfa=0x%lx\n", 99 c->sigcontext_format, c->sigcontext_addr, c->dwarf.cfa); 100 #endif 101 return -UNW_EBADFRAME; 102 } 103 104 #ifndef UNW_REMOTE_ONLY 105 HIDDEN void * 106 x86_64_r_uc_addr (ucontext_t *uc, int reg) 107 { 108 /* NOTE: common_init() in init.h inlines these for fast path access. */ 109 void *addr; 110 111 switch (reg) 112 { 113 case UNW_X86_64_R8: addr = &uc->uc_mcontext.gregs[REG_R8]; break; 114 case UNW_X86_64_R9: addr = &uc->uc_mcontext.gregs[REG_R9]; break; 115 case UNW_X86_64_R10: addr = &uc->uc_mcontext.gregs[REG_R10]; break; 116 case UNW_X86_64_R11: addr = &uc->uc_mcontext.gregs[REG_R11]; break; 117 case UNW_X86_64_R12: addr = &uc->uc_mcontext.gregs[REG_R12]; break; 118 case UNW_X86_64_R13: addr = &uc->uc_mcontext.gregs[REG_R13]; break; 119 case UNW_X86_64_R14: addr = &uc->uc_mcontext.gregs[REG_R14]; break; 120 case UNW_X86_64_R15: addr = &uc->uc_mcontext.gregs[REG_R15]; break; 121 case UNW_X86_64_RDI: addr = &uc->uc_mcontext.gregs[REG_RDI]; break; 122 case UNW_X86_64_RSI: addr = &uc->uc_mcontext.gregs[REG_RSI]; break; 123 case UNW_X86_64_RBP: addr = &uc->uc_mcontext.gregs[REG_RBP]; break; 124 case UNW_X86_64_RBX: addr = &uc->uc_mcontext.gregs[REG_RBX]; break; 125 case UNW_X86_64_RDX: addr = &uc->uc_mcontext.gregs[REG_RDX]; break; 126 case UNW_X86_64_RAX: addr = &uc->uc_mcontext.gregs[REG_RAX]; break; 127 case UNW_X86_64_RCX: addr = &uc->uc_mcontext.gregs[REG_RCX]; break; 128 case UNW_X86_64_RSP: addr = &uc->uc_mcontext.gregs[REG_RSP]; break; 129 case UNW_X86_64_RIP: addr = &uc->uc_mcontext.gregs[REG_RIP]; break; 130 131 default: 132 addr = NULL; 133 } 134 return addr; 135 } 136 137 /* sigreturn() is a no-op on x86_64 glibc. */ 138 HIDDEN NORETURN void 139 x86_64_sigreturn (unw_cursor_t *cursor) 140 { 141 struct cursor *c = (struct cursor *) cursor; 142 struct sigcontext *sc = (struct sigcontext *) c->sigcontext_addr; 143 144 Debug (8, "resuming at ip=%llx via sigreturn(%p)\n", 145 (unsigned long long) c->dwarf.ip, sc); 146 __asm__ __volatile__ ("mov %0, %%rsp;" 147 "mov %1, %%rax;" 148 "syscall" 149 :: "r"(sc), "i"(SYS_rt_sigreturn) 150 : "memory"); 151 abort(); 152 } 153 154 #endif 155