| /* Copyright (C) 2000, 2001, 2003 Free Software Foundation, Inc. |
| Contributed by Richard Henderson <rth@cygnus.com>. |
| |
| 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 2, 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. |
| |
| You should have received a copy of the GNU General Public License |
| along with GCC; see the file COPYING. If not, write to |
| the Free Software Foundation, 59 Temple Place - Suite 330, |
| Boston, MA 02111-1307, USA. */ |
| |
| /* As a special exception, if you link this library with other files, |
| some of which are compiled with GCC, to produce an executable, |
| this library does not by itself cause the resulting executable |
| to be covered by the GNU General Public License. |
| This exception does not however invalidate any other reasons why |
| the executable file might be covered by the GNU General Public License. */ |
| |
| /* Locate the FDE entry for a given address, using glibc ld.so routines |
| to avoid register/deregister calls at DSO load/unload. */ |
| |
| #ifndef _GNU_SOURCE |
| #define _GNU_SOURCE 1 |
| #endif |
| #include "config.h" |
| #include <stddef.h> |
| #include <stdlib.h> |
| #include <link.h> |
| #include "unwind-ia64.h" |
| |
| #if __GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ < 2) \ |
| || (__GLIBC__ == 2 && __GLIBC_MINOR__ == 2 && !defined(DT_CONFIG)) |
| # error You need GLIBC 2.2.4 or later on IA-64 Linux |
| #endif |
| |
| struct unw_ia64_callback_data |
| { |
| Elf64_Addr pc; |
| unsigned long *segment_base; |
| unsigned long *gp; |
| struct unw_table_entry *ret; |
| }; |
| |
| static int |
| _Unwind_IteratePhdrCallback (struct dl_phdr_info *info, size_t size, void *ptr) |
| { |
| struct unw_ia64_callback_data *data = (struct unw_ia64_callback_data *) ptr; |
| const Elf64_Phdr *phdr, *p_unwind, *p_dynamic; |
| long n, match; |
| Elf64_Addr load_base, seg_base; |
| struct unw_table_entry *f_base, *f; |
| size_t lo, hi; |
| |
| /* Make sure struct dl_phdr_info is at least as big as we need. */ |
| if (size < offsetof (struct dl_phdr_info, dlpi_phnum) |
| + sizeof (info->dlpi_phnum)) |
| return -1; |
| |
| match = 0; |
| phdr = info->dlpi_phdr; |
| load_base = info->dlpi_addr; |
| p_unwind = NULL; |
| p_dynamic = NULL; |
| seg_base = ~(Elf64_Addr) 0; |
| |
| /* See if PC falls into one of the loaded segments. Find the unwind |
| segment at the same time. */ |
| for (n = info->dlpi_phnum; --n >= 0; phdr++) |
| { |
| if (phdr->p_type == PT_LOAD) |
| { |
| Elf64_Addr vaddr = phdr->p_vaddr + load_base; |
| if (data->pc >= vaddr && data->pc < vaddr + phdr->p_memsz) |
| match = 1; |
| if (vaddr < seg_base) |
| seg_base = vaddr; |
| } |
| else if (phdr->p_type == PT_IA_64_UNWIND) |
| p_unwind = phdr; |
| else if (phdr->p_type == PT_DYNAMIC) |
| p_dynamic = phdr; |
| } |
| if (!match || !p_unwind) |
| return 0; |
| |
| /* Search for the FDE within the unwind segment. */ |
| |
| f_base = (struct unw_table_entry *) (p_unwind->p_vaddr + load_base); |
| lo = 0; |
| hi = p_unwind->p_memsz / sizeof (struct unw_table_entry); |
| |
| while (lo < hi) |
| { |
| size_t mid = (lo + hi) / 2; |
| |
| f = f_base + mid; |
| if (data->pc < f->start_offset + seg_base) |
| hi = mid; |
| else if (data->pc >= f->end_offset + seg_base) |
| lo = mid + 1; |
| else |
| goto found; |
| } |
| /* No need to search for further libraries when we know pc is contained |
| in this library. */ |
| return 1; |
| |
| found: |
| *data->segment_base = seg_base; |
| *data->gp = 0; |
| data->ret = f; |
| |
| if (p_dynamic) |
| { |
| /* For dynamically linked executables and shared libraries, |
| DT_PLTGOT is the gp value for that object. */ |
| Elf64_Dyn *dyn = (Elf64_Dyn *)(p_dynamic->p_vaddr + load_base); |
| for (; dyn->d_tag != DT_NULL ; dyn++) |
| if (dyn->d_tag == DT_PLTGOT) |
| { |
| /* On IA-64, _DYNAMIC is writable and GLIBC has relocated it. */ |
| *data->gp = dyn->d_un.d_ptr; |
| break; |
| } |
| } |
| else |
| { |
| /* Otherwise this is a static executable with no _DYNAMIC. |
| The gp is constant program-wide. */ |
| register unsigned long gp __asm__("gp"); |
| *data->gp = gp; |
| } |
| |
| return 1; |
| } |
| |
| /* Return a pointer to the unwind table entry for the function |
| containing PC. */ |
| |
| struct unw_table_entry * |
| _Unwind_FindTableEntry (void *pc, unsigned long *segment_base, |
| unsigned long *gp) |
| { |
| struct unw_ia64_callback_data data; |
| |
| data.pc = (Elf64_Addr) pc; |
| data.segment_base = segment_base; |
| data.gp = gp; |
| data.ret = NULL; |
| |
| if (dl_iterate_phdr (_Unwind_IteratePhdrCallback, &data) < 0) |
| return NULL; |
| |
| return data.ret; |
| } |