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-rw-r--r--gcc-4.9/libgcc/unwind-dw2-fde-dip.c481
1 files changed, 481 insertions, 0 deletions
diff --git a/gcc-4.9/libgcc/unwind-dw2-fde-dip.c b/gcc-4.9/libgcc/unwind-dw2-fde-dip.c
new file mode 100644
index 000000000..d6c052165
--- /dev/null
+++ b/gcc-4.9/libgcc/unwind-dw2-fde-dip.c
@@ -0,0 +1,481 @@
+/* Copyright (C) 2001-2014 Free Software Foundation, Inc.
+ Contributed by Jakub Jelinek <jakub@redhat.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 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/>. */
+
+/* Locate the FDE entry for a given address, using PT_GNU_EH_FRAME ELF
+ segment and dl_iterate_phdr to avoid register/deregister calls at
+ DSO load/unload. */
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE 1
+#endif
+
+#include "tconfig.h"
+#include "tsystem.h"
+#if !defined(inhibit_libc) && !defined(__OpenBSD__)
+#include <elf.h> /* Get DT_CONFIG. */
+#endif
+#include "coretypes.h"
+#include "tm.h"
+#include "libgcc_tm.h"
+#include "dwarf2.h"
+#include "unwind.h"
+#define NO_BASE_OF_ENCODED_VALUE
+#include "unwind-pe.h"
+#include "unwind-dw2-fde.h"
+#include "unwind-compat.h"
+#include "gthr.h"
+
+#if !defined(inhibit_libc) && defined(HAVE_LD_EH_FRAME_HDR) \
+ && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) \
+ || (__GLIBC__ == 2 && __GLIBC_MINOR__ == 2 && defined(DT_CONFIG)))
+# define USE_PT_GNU_EH_FRAME
+#endif
+
+#if !defined(inhibit_libc) && defined(HAVE_LD_EH_FRAME_HDR) \
+ && defined(__BIONIC__)
+# define USE_PT_GNU_EH_FRAME
+#endif
+
+#if !defined(inhibit_libc) && defined(HAVE_LD_EH_FRAME_HDR) \
+ && defined(__FreeBSD__) && __FreeBSD__ >= 7
+# define ElfW __ElfN
+# define USE_PT_GNU_EH_FRAME
+#endif
+
+#if !defined(inhibit_libc) && defined(HAVE_LD_EH_FRAME_HDR) \
+ && defined(__OpenBSD__)
+# define ElfW(type) Elf_##type
+# define USE_PT_GNU_EH_FRAME
+#endif
+
+#if !defined(inhibit_libc) && defined(HAVE_LD_EH_FRAME_HDR) \
+ && defined(TARGET_DL_ITERATE_PHDR) \
+ && defined(__sun__) && defined(__svr4__)
+# define USE_PT_GNU_EH_FRAME
+#endif
+
+#if defined(USE_PT_GNU_EH_FRAME)
+
+#include <link.h>
+
+#ifndef __RELOC_POINTER
+# define __RELOC_POINTER(ptr, base) ((ptr) + (base))
+#endif
+
+static const fde * _Unwind_Find_registered_FDE (void *pc, struct dwarf_eh_bases *bases);
+
+#define _Unwind_Find_FDE _Unwind_Find_registered_FDE
+#include "unwind-dw2-fde.c"
+#undef _Unwind_Find_FDE
+
+#ifndef PT_GNU_EH_FRAME
+#define PT_GNU_EH_FRAME (PT_LOOS + 0x474e550)
+#endif
+
+struct unw_eh_callback_data
+{
+ _Unwind_Ptr pc;
+ void *tbase;
+ void *dbase;
+ void *func;
+ const fde *ret;
+ int check_cache;
+};
+
+struct unw_eh_frame_hdr
+{
+ unsigned char version;
+ unsigned char eh_frame_ptr_enc;
+ unsigned char fde_count_enc;
+ unsigned char table_enc;
+};
+
+#define FRAME_HDR_CACHE_SIZE 8
+
+static struct frame_hdr_cache_element
+{
+ _Unwind_Ptr pc_low;
+ _Unwind_Ptr pc_high;
+ _Unwind_Ptr load_base;
+ const ElfW(Phdr) *p_eh_frame_hdr;
+ const ElfW(Phdr) *p_dynamic;
+ struct frame_hdr_cache_element *link;
+} frame_hdr_cache[FRAME_HDR_CACHE_SIZE];
+
+static struct frame_hdr_cache_element *frame_hdr_cache_head;
+
+/* Like base_of_encoded_value, but take the base from a struct
+ unw_eh_callback_data instead of an _Unwind_Context. */
+
+static _Unwind_Ptr
+base_from_cb_data (unsigned char encoding, struct unw_eh_callback_data *data)
+{
+ if (encoding == DW_EH_PE_omit)
+ return 0;
+
+ switch (encoding & 0x70)
+ {
+ case DW_EH_PE_absptr:
+ case DW_EH_PE_pcrel:
+ case DW_EH_PE_aligned:
+ return 0;
+
+ case DW_EH_PE_textrel:
+ return (_Unwind_Ptr) data->tbase;
+ case DW_EH_PE_datarel:
+ return (_Unwind_Ptr) data->dbase;
+ default:
+ gcc_unreachable ();
+ }
+}
+
+static int
+_Unwind_IteratePhdrCallback (struct dl_phdr_info *info, size_t size, void *ptr)
+{
+ struct unw_eh_callback_data *data = (struct unw_eh_callback_data *) ptr;
+ const ElfW(Phdr) *phdr, *p_eh_frame_hdr, *p_dynamic;
+ long n, match;
+#ifdef __FRV_FDPIC__
+ struct elf32_fdpic_loadaddr load_base;
+#else
+ _Unwind_Ptr load_base;
+#endif
+ const unsigned char *p;
+ const struct unw_eh_frame_hdr *hdr;
+ _Unwind_Ptr eh_frame;
+ struct object ob;
+ _Unwind_Ptr pc_low = 0, pc_high = 0;
+
+ struct ext_dl_phdr_info
+ {
+ ElfW(Addr) dlpi_addr;
+ const char *dlpi_name;
+ const ElfW(Phdr) *dlpi_phdr;
+ ElfW(Half) dlpi_phnum;
+ unsigned long long int dlpi_adds;
+ unsigned long long int dlpi_subs;
+ };
+
+ match = 0;
+ phdr = info->dlpi_phdr;
+ load_base = info->dlpi_addr;
+ p_eh_frame_hdr = NULL;
+ p_dynamic = NULL;
+
+ struct frame_hdr_cache_element *prev_cache_entry = NULL,
+ *last_cache_entry = NULL;
+
+ if (data->check_cache && size >= sizeof (struct ext_dl_phdr_info))
+ {
+ static unsigned long long adds = -1ULL, subs;
+ struct ext_dl_phdr_info *einfo = (struct ext_dl_phdr_info *) info;
+
+ /* We use a least recently used cache replacement policy. Also,
+ the most recently used cache entries are placed at the head
+ of the search chain. */
+
+ if (einfo->dlpi_adds == adds && einfo->dlpi_subs == subs)
+ {
+ /* Find data->pc in shared library cache.
+ Set load_base, p_eh_frame_hdr and p_dynamic
+ plus match from the cache and goto
+ "Read .eh_frame_hdr header." below. */
+
+ struct frame_hdr_cache_element *cache_entry;
+
+ for (cache_entry = frame_hdr_cache_head;
+ cache_entry;
+ cache_entry = cache_entry->link)
+ {
+ if (data->pc >= cache_entry->pc_low
+ && data->pc < cache_entry->pc_high)
+ {
+ load_base = cache_entry->load_base;
+ p_eh_frame_hdr = cache_entry->p_eh_frame_hdr;
+ p_dynamic = cache_entry->p_dynamic;
+
+ /* And move the entry we're using to the head. */
+ if (cache_entry != frame_hdr_cache_head)
+ {
+ prev_cache_entry->link = cache_entry->link;
+ cache_entry->link = frame_hdr_cache_head;
+ frame_hdr_cache_head = cache_entry;
+ }
+ goto found;
+ }
+
+ last_cache_entry = cache_entry;
+ /* Exit early if we found an unused entry. */
+ if ((cache_entry->pc_low | cache_entry->pc_high) == 0)
+ break;
+ if (cache_entry->link != NULL)
+ prev_cache_entry = cache_entry;
+ }
+ }
+ else
+ {
+ adds = einfo->dlpi_adds;
+ subs = einfo->dlpi_subs;
+ /* Initialize the cache. Create a chain of cache entries,
+ with the final one terminated by a NULL link. */
+ int i;
+ for (i = 0; i < FRAME_HDR_CACHE_SIZE; i++)
+ {
+ frame_hdr_cache[i].pc_low = 0;
+ frame_hdr_cache[i].pc_high = 0;
+ frame_hdr_cache[i].link = &frame_hdr_cache[i+1];
+ }
+ frame_hdr_cache[i-1].link = NULL;
+ frame_hdr_cache_head = &frame_hdr_cache[0];
+ data->check_cache = 0;
+ }
+ }
+
+ /* 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;
+
+ /* See if PC falls into one of the loaded segments. Find the eh_frame
+ segment at the same time. */
+ for (n = info->dlpi_phnum; --n >= 0; phdr++)
+ {
+ if (phdr->p_type == PT_LOAD)
+ {
+ _Unwind_Ptr vaddr = (_Unwind_Ptr)
+ __RELOC_POINTER (phdr->p_vaddr, load_base);
+ if (data->pc >= vaddr && data->pc < vaddr + phdr->p_memsz)
+ {
+ match = 1;
+ pc_low = vaddr;
+ pc_high = vaddr + phdr->p_memsz;
+ }
+ }
+ else if (phdr->p_type == PT_GNU_EH_FRAME)
+ p_eh_frame_hdr = phdr;
+#ifdef PT_SUNW_UNWIND
+ /* Sun ld emits PT_SUNW_UNWIND .eh_frame_hdr sections instead of
+ PT_SUNW_EH_FRAME/PT_GNU_EH_FRAME, so accept them as well. */
+ else if (phdr->p_type == PT_SUNW_UNWIND)
+ p_eh_frame_hdr = phdr;
+#endif
+ else if (phdr->p_type == PT_DYNAMIC)
+ p_dynamic = phdr;
+ }
+
+ if (!match)
+ return 0;
+
+ if (size >= sizeof (struct ext_dl_phdr_info))
+ {
+ /* Move the cache entry we're about to overwrite to the head of
+ the list. If either last_cache_entry or prev_cache_entry are
+ NULL, that cache entry is already at the head. */
+ if (last_cache_entry != NULL && prev_cache_entry != NULL)
+ {
+ prev_cache_entry->link = last_cache_entry->link;
+ last_cache_entry->link = frame_hdr_cache_head;
+ frame_hdr_cache_head = last_cache_entry;
+ }
+
+ frame_hdr_cache_head->load_base = load_base;
+ frame_hdr_cache_head->p_eh_frame_hdr = p_eh_frame_hdr;
+ frame_hdr_cache_head->p_dynamic = p_dynamic;
+ frame_hdr_cache_head->pc_low = pc_low;
+ frame_hdr_cache_head->pc_high = pc_high;
+ }
+
+ found:
+
+ if (!p_eh_frame_hdr)
+ return 0;
+
+ /* Read .eh_frame_hdr header. */
+ hdr = (const struct unw_eh_frame_hdr *)
+ __RELOC_POINTER (p_eh_frame_hdr->p_vaddr, load_base);
+ if (hdr->version != 1)
+ return 1;
+
+#ifdef CRT_GET_RFIB_DATA
+# ifdef __i386__
+ data->dbase = NULL;
+ if (p_dynamic)
+ {
+ /* For dynamically linked executables and shared libraries,
+ DT_PLTGOT is the gp value for that object. */
+ ElfW(Dyn) *dyn = (ElfW(Dyn) *)
+ __RELOC_POINTER (p_dynamic->p_vaddr, load_base);
+ for (; dyn->d_tag != DT_NULL ; dyn++)
+ if (dyn->d_tag == DT_PLTGOT)
+ {
+ data->dbase = (void *) dyn->d_un.d_ptr;
+#if defined __linux__
+ /* On IA-32 Linux, _DYNAMIC is writable and GLIBC has
+ relocated it. */
+#elif defined __sun__ && defined __svr4__
+ /* On Solaris 2/x86, we need to do this ourselves. */
+ data->dbase += load_base;
+#endif
+ break;
+ }
+ }
+# elif defined __FRV_FDPIC__ && defined __linux__
+ data->dbase = load_base.got_value;
+# elif defined __x86_64__ && defined __sun__ && defined __svr4__
+ /* While CRT_GET_RFIB_DATA is also defined for 64-bit Solaris 10+/x86, it
+ doesn't apply since it uses DW_EH_PE_pcrel encoding. */
+# else
+# error What is DW_EH_PE_datarel base on this platform?
+# endif
+#endif
+
+ p = read_encoded_value_with_base (hdr->eh_frame_ptr_enc,
+ base_from_cb_data (hdr->eh_frame_ptr_enc,
+ data),
+ (const unsigned char *) (hdr + 1),
+ &eh_frame);
+
+ /* We require here specific table encoding to speed things up.
+ Also, DW_EH_PE_datarel here means using PT_GNU_EH_FRAME start
+ as base, not the processor specific DW_EH_PE_datarel. */
+ if (hdr->fde_count_enc != DW_EH_PE_omit
+ && hdr->table_enc == (DW_EH_PE_datarel | DW_EH_PE_sdata4))
+ {
+ _Unwind_Ptr fde_count;
+
+ p = read_encoded_value_with_base (hdr->fde_count_enc,
+ base_from_cb_data (hdr->fde_count_enc,
+ data),
+ p, &fde_count);
+ /* Shouldn't happen. */
+ if (fde_count == 0)
+ return 1;
+ if ((((_Unwind_Ptr) p) & 3) == 0)
+ {
+ struct fde_table {
+ signed initial_loc __attribute__ ((mode (SI)));
+ signed fde __attribute__ ((mode (SI)));
+ };
+ const struct fde_table *table = (const struct fde_table *) p;
+ size_t lo, hi, mid;
+ _Unwind_Ptr data_base = (_Unwind_Ptr) hdr;
+ fde *f;
+ unsigned int f_enc, f_enc_size;
+ _Unwind_Ptr range;
+
+ mid = fde_count - 1;
+ if (data->pc < table[0].initial_loc + data_base)
+ return 1;
+ else if (data->pc < table[mid].initial_loc + data_base)
+ {
+ lo = 0;
+ hi = mid;
+
+ while (lo < hi)
+ {
+ mid = (lo + hi) / 2;
+ if (data->pc < table[mid].initial_loc + data_base)
+ hi = mid;
+ else if (data->pc >= table[mid + 1].initial_loc + data_base)
+ lo = mid + 1;
+ else
+ break;
+ }
+
+ gcc_assert (lo < hi);
+ }
+
+ f = (fde *) (table[mid].fde + data_base);
+ f_enc = get_fde_encoding (f);
+ f_enc_size = size_of_encoded_value (f_enc);
+ read_encoded_value_with_base (f_enc & 0x0f, 0,
+ &f->pc_begin[f_enc_size], &range);
+ if (data->pc < table[mid].initial_loc + data_base + range)
+ data->ret = f;
+ data->func = (void *) (table[mid].initial_loc + data_base);
+ return 1;
+ }
+ }
+
+ /* We have no sorted search table, so need to go the slow way.
+ As soon as GLIBC will provide API so to notify that a library has been
+ removed, we could cache this (and thus use search_object). */
+ ob.pc_begin = NULL;
+ ob.tbase = data->tbase;
+ ob.dbase = data->dbase;
+ ob.u.single = (fde *) eh_frame;
+ ob.s.i = 0;
+ ob.s.b.mixed_encoding = 1; /* Need to assume worst case. */
+ data->ret = linear_search_fdes (&ob, (fde *) eh_frame, (void *) data->pc);
+ if (data->ret != NULL)
+ {
+ _Unwind_Ptr func;
+ unsigned int encoding = get_fde_encoding (data->ret);
+
+ read_encoded_value_with_base (encoding,
+ base_from_cb_data (encoding, data),
+ data->ret->pc_begin, &func);
+ data->func = (void *) func;
+ }
+ return 1;
+}
+
+const fde *
+_Unwind_Find_FDE (void *pc, struct dwarf_eh_bases *bases)
+{
+ struct unw_eh_callback_data data;
+ const fde *ret;
+
+ ret = _Unwind_Find_registered_FDE (pc, bases);
+ if (ret != NULL)
+ return ret;
+
+ data.pc = (_Unwind_Ptr) pc;
+ data.tbase = NULL;
+ data.dbase = NULL;
+ data.func = NULL;
+ data.ret = NULL;
+ data.check_cache = 1;
+
+ if (dl_iterate_phdr (_Unwind_IteratePhdrCallback, &data) < 0)
+ return NULL;
+
+ if (data.ret)
+ {
+ bases->tbase = data.tbase;
+ bases->dbase = data.dbase;
+ bases->func = data.func;
+ }
+ return data.ret;
+}
+
+#else
+/* Prevent multiple include of header files. */
+#define _Unwind_Find_FDE _Unwind_Find_FDE
+#include "unwind-dw2-fde.c"
+#endif
+
+#if defined (USE_GAS_SYMVER) && defined (SHARED) && defined (USE_LIBUNWIND_EXCEPTIONS)
+alias (_Unwind_Find_FDE);
+#endif