/* Read ELF (Executable and Linking Format) object files for GDB.
- Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
- 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
- Free Software Foundation, Inc.
+ Copyright (C) 1991-2013 Free Software Foundation, Inc.
Written by Fred Fish at Cygnus Support.
#include "complaints.h"
#include "demangle.h"
#include "psympriv.h"
+#include "filenames.h"
+#include "probe.h"
+#include "arch-utils.h"
+#include "gdbtypes.h"
+#include "value.h"
+#include "infcall.h"
+#include "gdbthread.h"
+#include "regcache.h"
+#include "bcache.h"
+#include "gdb_bfd.h"
extern void _initialize_elfread (void);
asection *mdebugsect; /* Section pointer for .mdebug section */
};
+/* Per-objfile data for probe info. */
+
+static const struct objfile_data *probe_key = NULL;
+
static void free_elfinfo (void *);
+/* Minimal symbols located at the GOT entries for .plt - that is the real
+ pointer where the given entry will jump to. It gets updated by the real
+ function address during lazy ld.so resolving in the inferior. These
+ minimal symbols are indexed for <tab>-completion. */
+
+#define SYMBOL_GOT_PLT_SUFFIX "@got.plt"
+
/* Locate the segments in ABFD. */
static struct symfile_segment_data *
binaries are not relocatable. */
if (bfd_get_section_size (sect) > 0 && j == num_segments
&& (bfd_get_section_flags (abfd, sect) & SEC_LOAD) != 0)
- warning (_("Loadable segment \"%s\" outside of ELF segments"),
+ warning (_("Loadable section \"%s\" outside of ELF segments"),
bfd_section_name (abfd, sect));
}
{
struct gdbarch *gdbarch = get_objfile_arch (objfile);
- if (ms_type == mst_text || ms_type == mst_file_text)
- address = gdbarch_smash_text_address (gdbarch, address);
+ if (ms_type == mst_text || ms_type == mst_file_text
+ || ms_type == mst_text_gnu_ifunc)
+ address = gdbarch_addr_bits_remove (gdbarch, address);
return prim_record_minimal_symbol_full (name, name_len, copy_name, address,
- ms_type, bfd_section->index,
- bfd_section, objfile);
+ ms_type,
+ gdb_bfd_section_index (objfile->obfd,
+ bfd_section),
+ objfile);
}
-/*
-
- LOCAL FUNCTION
-
- elf_symtab_read -- read the symbol table of an ELF file
-
- SYNOPSIS
-
- void elf_symtab_read (struct objfile *objfile, int type,
- long number_of_symbols, asymbol **symbol_table)
-
- DESCRIPTION
+/* Read the symbol table of an ELF file.
Given an objfile, a symbol table, and a flag indicating whether the
symbol table contains regular, dynamic, or synthetic symbols, add all
defined in the ELF symbol table, which can be used to locate
the beginnings of sections from each ".o" file that was linked to
form the executable objfile. We gather any such info and record it
- in data structures hung off the objfile's private data.
-
- */
+ in data structures hung off the objfile's private data. */
#define ST_REGULAR 0
#define ST_DYNAMIC 1
seen any section info for it yet. */
asymbol *filesym = 0;
/* Name of filesym. This is either a constant string or is saved on
- the objfile's obstack. */
- char *filesymname = "";
- struct dbx_symfile_info *dbx = objfile->deprecated_sym_stab_info;
+ the objfile's filename cache. */
+ const char *filesymname = "";
+ struct dbx_symfile_info *dbx = DBX_SYMFILE_INFO (objfile);
int stripped = (bfd_get_symcount (objfile->obfd) == 0);
- struct cleanup *back_to = make_cleanup (null_cleanup, NULL);
for (i = 0; i < number_of_symbols; i++)
{
continue;
}
- offset = ANOFFSET (objfile->section_offsets, sym->section->index);
+ offset = ANOFFSET (objfile->section_offsets,
+ gdb_bfd_section_index (objfile->obfd, sym->section));
if (type == ST_DYNAMIC
- && sym->section == &bfd_und_section
+ && sym->section == bfd_und_section_ptr
&& (sym->flags & BSF_FUNCTION))
{
struct minimal_symbol *msym;
bfd *abfd = objfile->obfd;
- asection *sect;
+ asection *sect;
/* Symbol is a reference to a function defined in
a shared library.
if (!sect)
continue;
- symaddr += ANOFFSET (objfile->section_offsets, sect->index);
+ /* On ia64-hpux, we have discovered that the system linker
+ adds undefined symbols with nonzero addresses that cannot
+ be right (their address points inside the code of another
+ function in the .text section). This creates problems
+ when trying to determine which symbol corresponds to
+ a given address.
+
+ We try to detect those buggy symbols by checking which
+ section we think they correspond to. Normally, PLT symbols
+ are stored inside their own section, and the typical name
+ for that section is ".plt". So, if there is a ".plt"
+ section, and yet the section name of our symbol does not
+ start with ".plt", we ignore that symbol. */
+ if (strncmp (sect->name, ".plt", 4) != 0
+ && bfd_get_section_by_name (abfd, ".plt") != NULL)
+ continue;
+
+ symaddr += ANOFFSET (objfile->section_offsets,
+ gdb_bfd_section_index (objfile->obfd, sect));
msym = record_minimal_symbol
(sym->name, strlen (sym->name), copy_names,
sectinfo = NULL;
}
filesym = sym;
- filesymname =
- obsavestring ((char *) filesym->name, strlen (filesym->name),
- &objfile->objfile_obstack);
+ filesymname = bcache (filesym->name, strlen (filesym->name) + 1,
+ objfile->per_bfd->filename_cache);
}
else if (sym->flags & BSF_SECTION_SYM)
continue;
- else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK))
+ else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK
+ | BSF_GNU_UNIQUE))
{
struct minimal_symbol *msym;
symaddr = sym->value + sym->section->vma;
/* Relocate all non-absolute and non-TLS symbols by the
section offset. */
- if (sym->section != &bfd_abs_section
+ if (sym->section != bfd_abs_section_ptr
&& !(sym->section->flags & SEC_THREAD_LOCAL))
{
symaddr += offset;
/* For non-absolute symbols, use the type of the section
they are relative to, to intuit text/data. Bfd provides
no way of figuring this out for absolute symbols. */
- if (sym->section == &bfd_abs_section)
+ if (sym->section == bfd_abs_section_ptr)
{
/* This is a hack to get the minimal symbol type
right for Irix 5, which has absolute addresses
NOTE: uweigand-20071112: Synthetic symbols do not
have an ELF-private part, so do not touch those. */
- unsigned int shndx = type == ST_SYNTHETIC ? 0 :
+ unsigned int shndx = type == ST_SYNTHETIC ? 0 :
((elf_symbol_type *) sym)->internal_elf_sym.st_shndx;
switch (shndx)
}
else if (sym->section->flags & SEC_CODE)
{
- if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
+ if (sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_GNU_UNIQUE))
{
- ms_type = mst_text;
+ if (sym->flags & BSF_GNU_INDIRECT_FUNCTION)
+ ms_type = mst_text_gnu_ifunc;
+ else
+ ms_type = mst_text;
}
- else if ((sym->name[0] == '.' && sym->name[1] == 'L')
+ /* The BSF_SYNTHETIC check is there to omit ppc64 function
+ descriptors mistaken for static functions starting with 'L'.
+ */
+ else if ((sym->name[0] == '.' && sym->name[1] == 'L'
+ && (sym->flags & BSF_SYNTHETIC) == 0)
|| ((sym->flags & BSF_LOCAL)
&& sym->name[0] == '$'
&& sym->name[1] == 'L'))
}
else if (sym->section->flags & SEC_ALLOC)
{
- if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
+ if (sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_GNU_UNIQUE))
{
if (sym->section->flags & SEC_LOAD)
{
already includes one element, so we
need to allocate max_index aadditional
elements. */
- size = (sizeof (struct stab_section_info)
+ size = (sizeof (struct stab_section_info)
+ (sizeof (CORE_ADDR) * max_index));
sectinfo = (struct stab_section_info *)
xmalloc (size);
- make_cleanup (xfree, sectinfo);
memset (sectinfo, 0, size);
sectinfo->num_sections = max_index;
if (filesym == NULL)
symaddr = sym->value + sym->section->vma;
/* Relocate non-absolute symbols by the
section offset. */
- if (sym->section != &bfd_abs_section)
+ if (sym->section != bfd_abs_section_ptr)
symaddr += offset;
sectinfo->sections[special_local_sect] = symaddr;
/* The special local symbols don't go in the
else
{
/* FIXME: Solaris2 shared libraries include lots of
- odd "absolute" and "undefined" symbols, that play
+ odd "absolute" and "undefined" symbols, that play
hob with actions like finding what function the PC
is in. Ignore them if they aren't text, data, or bss. */
/* ms_type = mst_unknown; */
if (msym)
{
- /* Pass symbol size field in via BFD. FIXME!!! */
- elf_symbol_type *elf_sym;
-
/* NOTE: uweigand-20071112: A synthetic symbol does not have an
- ELF-private part. However, in some cases (e.g. synthetic
- 'dot' symbols on ppc64) the udata.p entry is set to point back
- to the original ELF symbol it was derived from. Get the size
- from that symbol. */
+ ELF-private part. */
if (type != ST_SYNTHETIC)
- elf_sym = (elf_symbol_type *) sym;
- else
- elf_sym = (elf_symbol_type *) sym->udata.p;
+ {
+ /* Pass symbol size field in via BFD. FIXME!!! */
+ elf_symbol_type *elf_sym = (elf_symbol_type *) sym;
+ SET_MSYMBOL_SIZE (msym, elf_sym->internal_elf_sym.st_size);
+ }
- if (elf_sym)
- MSYMBOL_SIZE(msym) = elf_sym->internal_elf_sym.st_size;
-
msym->filename = filesymname;
gdbarch_elf_make_msymbol_special (gdbarch, sym, msym);
}
+ /* If we see a default versioned symbol, install it under
+ its version-less name. */
+ if (msym != NULL)
+ {
+ const char *atsign = strchr (sym->name, '@');
+
+ if (atsign != NULL && atsign[1] == '@' && atsign > sym->name)
+ {
+ int len = atsign - sym->name;
+
+ record_minimal_symbol (sym->name, len, 1, symaddr,
+ ms_type, sym->section, objfile);
+ }
+ }
+
/* For @plt symbols, also record a trampoline to the
destination symbol. The @plt symbol will be used in
disassembly, and the trampoline will be used when we are
sym->section, objfile);
if (mtramp)
{
- MSYMBOL_SIZE (mtramp) = MSYMBOL_SIZE (msym);
+ SET_MSYMBOL_SIZE (mtramp, MSYMBOL_SIZE (msym));
+ mtramp->created_by_gdb = 1;
mtramp->filename = filesymname;
gdbarch_elf_make_msymbol_special (gdbarch, sym, mtramp);
}
}
}
}
+}
+
+/* Build minimal symbols named `function@got.plt' (see SYMBOL_GOT_PLT_SUFFIX)
+ for later look ups of which function to call when user requests
+ a STT_GNU_IFUNC function. As the STT_GNU_IFUNC type is found at the target
+ library defining `function' we cannot yet know while reading OBJFILE which
+ of the SYMBOL_GOT_PLT_SUFFIX entries will be needed and later
+ DYN_SYMBOL_TABLE is no longer easily available for OBJFILE. */
+
+static void
+elf_rel_plt_read (struct objfile *objfile, asymbol **dyn_symbol_table)
+{
+ bfd *obfd = objfile->obfd;
+ const struct elf_backend_data *bed = get_elf_backend_data (obfd);
+ asection *plt, *relplt, *got_plt;
+ int plt_elf_idx;
+ bfd_size_type reloc_count, reloc;
+ char *string_buffer = NULL;
+ size_t string_buffer_size = 0;
+ struct cleanup *back_to;
+ struct gdbarch *gdbarch = get_objfile_arch (objfile);
+ struct type *ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
+ size_t ptr_size = TYPE_LENGTH (ptr_type);
+
+ if (objfile->separate_debug_objfile_backlink)
+ return;
+
+ plt = bfd_get_section_by_name (obfd, ".plt");
+ if (plt == NULL)
+ return;
+ plt_elf_idx = elf_section_data (plt)->this_idx;
+
+ got_plt = bfd_get_section_by_name (obfd, ".got.plt");
+ if (got_plt == NULL)
+ return;
+
+ /* This search algorithm is from _bfd_elf_canonicalize_dynamic_reloc. */
+ for (relplt = obfd->sections; relplt != NULL; relplt = relplt->next)
+ if (elf_section_data (relplt)->this_hdr.sh_info == plt_elf_idx
+ && (elf_section_data (relplt)->this_hdr.sh_type == SHT_REL
+ || elf_section_data (relplt)->this_hdr.sh_type == SHT_RELA))
+ break;
+ if (relplt == NULL)
+ return;
+
+ if (! bed->s->slurp_reloc_table (obfd, relplt, dyn_symbol_table, TRUE))
+ return;
+
+ back_to = make_cleanup (free_current_contents, &string_buffer);
+
+ reloc_count = relplt->size / elf_section_data (relplt)->this_hdr.sh_entsize;
+ for (reloc = 0; reloc < reloc_count; reloc++)
+ {
+ const char *name;
+ struct minimal_symbol *msym;
+ CORE_ADDR address;
+ const size_t got_suffix_len = strlen (SYMBOL_GOT_PLT_SUFFIX);
+ size_t name_len;
+
+ name = bfd_asymbol_name (*relplt->relocation[reloc].sym_ptr_ptr);
+ name_len = strlen (name);
+ address = relplt->relocation[reloc].address;
+
+ /* Does the pointer reside in the .got.plt section? */
+ if (!(bfd_get_section_vma (obfd, got_plt) <= address
+ && address < bfd_get_section_vma (obfd, got_plt)
+ + bfd_get_section_size (got_plt)))
+ continue;
+
+ /* We cannot check if NAME is a reference to mst_text_gnu_ifunc as in
+ OBJFILE the symbol is undefined and the objfile having NAME defined
+ may not yet have been loaded. */
+
+ if (string_buffer_size < name_len + got_suffix_len + 1)
+ {
+ string_buffer_size = 2 * (name_len + got_suffix_len);
+ string_buffer = xrealloc (string_buffer, string_buffer_size);
+ }
+ memcpy (string_buffer, name, name_len);
+ memcpy (&string_buffer[name_len], SYMBOL_GOT_PLT_SUFFIX,
+ got_suffix_len + 1);
+
+ msym = record_minimal_symbol (string_buffer, name_len + got_suffix_len,
+ 1, address, mst_slot_got_plt, got_plt,
+ objfile);
+ if (msym)
+ SET_MSYMBOL_SIZE (msym, ptr_size);
+ }
+
do_cleanups (back_to);
}
-struct build_id
- {
- size_t size;
- gdb_byte data[1];
- };
+/* The data pointer is htab_t for gnu_ifunc_record_cache_unchecked. */
+
+static const struct objfile_data *elf_objfile_gnu_ifunc_cache_data;
+
+/* Map function names to CORE_ADDR in elf_objfile_gnu_ifunc_cache_data. */
+
+struct elf_gnu_ifunc_cache
+{
+ /* This is always a function entry address, not a function descriptor. */
+ CORE_ADDR addr;
+
+ char name[1];
+};
+
+/* htab_hash for elf_objfile_gnu_ifunc_cache_data. */
+
+static hashval_t
+elf_gnu_ifunc_cache_hash (const void *a_voidp)
+{
+ const struct elf_gnu_ifunc_cache *a = a_voidp;
+
+ return htab_hash_string (a->name);
+}
+
+/* htab_eq for elf_objfile_gnu_ifunc_cache_data. */
+
+static int
+elf_gnu_ifunc_cache_eq (const void *a_voidp, const void *b_voidp)
+{
+ const struct elf_gnu_ifunc_cache *a = a_voidp;
+ const struct elf_gnu_ifunc_cache *b = b_voidp;
+
+ return strcmp (a->name, b->name) == 0;
+}
+
+/* Record the target function address of a STT_GNU_IFUNC function NAME is the
+ function entry address ADDR. Return 1 if NAME and ADDR are considered as
+ valid and therefore they were successfully recorded, return 0 otherwise.
+
+ Function does not expect a duplicate entry. Use
+ elf_gnu_ifunc_resolve_by_cache first to check if the entry for NAME already
+ exists. */
+
+static int
+elf_gnu_ifunc_record_cache (const char *name, CORE_ADDR addr)
+{
+ struct bound_minimal_symbol msym;
+ asection *sect;
+ struct objfile *objfile;
+ htab_t htab;
+ struct elf_gnu_ifunc_cache entry_local, *entry_p;
+ void **slot;
+
+ msym = lookup_minimal_symbol_by_pc (addr);
+ if (msym.minsym == NULL)
+ return 0;
+ if (SYMBOL_VALUE_ADDRESS (msym.minsym) != addr)
+ return 0;
+ /* minimal symbols have always SYMBOL_OBJ_SECTION non-NULL. */
+ sect = SYMBOL_OBJ_SECTION (msym.objfile, msym.minsym)->the_bfd_section;
+ objfile = msym.objfile;
+
+ /* If .plt jumps back to .plt the symbol is still deferred for later
+ resolution and it has no use for GDB. Besides ".text" this symbol can
+ reside also in ".opd" for ppc64 function descriptor. */
+ if (strcmp (bfd_get_section_name (objfile->obfd, sect), ".plt") == 0)
+ return 0;
+
+ htab = objfile_data (objfile, elf_objfile_gnu_ifunc_cache_data);
+ if (htab == NULL)
+ {
+ htab = htab_create_alloc_ex (1, elf_gnu_ifunc_cache_hash,
+ elf_gnu_ifunc_cache_eq,
+ NULL, &objfile->objfile_obstack,
+ hashtab_obstack_allocate,
+ dummy_obstack_deallocate);
+ set_objfile_data (objfile, elf_objfile_gnu_ifunc_cache_data, htab);
+ }
+
+ entry_local.addr = addr;
+ obstack_grow (&objfile->objfile_obstack, &entry_local,
+ offsetof (struct elf_gnu_ifunc_cache, name));
+ obstack_grow_str0 (&objfile->objfile_obstack, name);
+ entry_p = obstack_finish (&objfile->objfile_obstack);
+
+ slot = htab_find_slot (htab, entry_p, INSERT);
+ if (*slot != NULL)
+ {
+ struct elf_gnu_ifunc_cache *entry_found_p = *slot;
+ struct gdbarch *gdbarch = get_objfile_arch (objfile);
+
+ if (entry_found_p->addr != addr)
+ {
+ /* This case indicates buggy inferior program, the resolved address
+ should never change. */
+
+ warning (_("gnu-indirect-function \"%s\" has changed its resolved "
+ "function_address from %s to %s"),
+ name, paddress (gdbarch, entry_found_p->addr),
+ paddress (gdbarch, addr));
+ }
+
+ /* New ENTRY_P is here leaked/duplicate in the OBJFILE obstack. */
+ }
+ *slot = entry_p;
+
+ return 1;
+}
+
+/* Try to find the target resolved function entry address of a STT_GNU_IFUNC
+ function NAME. If the address is found it is stored to *ADDR_P (if ADDR_P
+ is not NULL) and the function returns 1. It returns 0 otherwise.
+
+ Only the elf_objfile_gnu_ifunc_cache_data hash table is searched by this
+ function. */
+
+static int
+elf_gnu_ifunc_resolve_by_cache (const char *name, CORE_ADDR *addr_p)
+{
+ struct objfile *objfile;
+
+ ALL_PSPACE_OBJFILES (current_program_space, objfile)
+ {
+ htab_t htab;
+ struct elf_gnu_ifunc_cache *entry_p;
+ void **slot;
+
+ htab = objfile_data (objfile, elf_objfile_gnu_ifunc_cache_data);
+ if (htab == NULL)
+ continue;
+
+ entry_p = alloca (sizeof (*entry_p) + strlen (name));
+ strcpy (entry_p->name, name);
+
+ slot = htab_find_slot (htab, entry_p, NO_INSERT);
+ if (slot == NULL)
+ continue;
+ entry_p = *slot;
+ gdb_assert (entry_p != NULL);
+
+ if (addr_p)
+ *addr_p = entry_p->addr;
+ return 1;
+ }
+
+ return 0;
+}
+
+/* Try to find the target resolved function entry address of a STT_GNU_IFUNC
+ function NAME. If the address is found it is stored to *ADDR_P (if ADDR_P
+ is not NULL) and the function returns 1. It returns 0 otherwise.
+
+ Only the SYMBOL_GOT_PLT_SUFFIX locations are searched by this function.
+ elf_gnu_ifunc_resolve_by_cache must have been already called for NAME to
+ prevent cache entries duplicates. */
+
+static int
+elf_gnu_ifunc_resolve_by_got (const char *name, CORE_ADDR *addr_p)
+{
+ char *name_got_plt;
+ struct objfile *objfile;
+ const size_t got_suffix_len = strlen (SYMBOL_GOT_PLT_SUFFIX);
+
+ name_got_plt = alloca (strlen (name) + got_suffix_len + 1);
+ sprintf (name_got_plt, "%s" SYMBOL_GOT_PLT_SUFFIX, name);
+
+ ALL_PSPACE_OBJFILES (current_program_space, objfile)
+ {
+ bfd *obfd = objfile->obfd;
+ struct gdbarch *gdbarch = get_objfile_arch (objfile);
+ struct type *ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
+ size_t ptr_size = TYPE_LENGTH (ptr_type);
+ CORE_ADDR pointer_address, addr;
+ asection *plt;
+ gdb_byte *buf = alloca (ptr_size);
+ struct minimal_symbol *msym;
+
+ msym = lookup_minimal_symbol (name_got_plt, NULL, objfile);
+ if (msym == NULL)
+ continue;
+ if (MSYMBOL_TYPE (msym) != mst_slot_got_plt)
+ continue;
+ pointer_address = SYMBOL_VALUE_ADDRESS (msym);
+
+ plt = bfd_get_section_by_name (obfd, ".plt");
+ if (plt == NULL)
+ continue;
+
+ if (MSYMBOL_SIZE (msym) != ptr_size)
+ continue;
+ if (target_read_memory (pointer_address, buf, ptr_size) != 0)
+ continue;
+ addr = extract_typed_address (buf, ptr_type);
+ addr = gdbarch_convert_from_func_ptr_addr (gdbarch, addr,
+ ¤t_target);
+
+ if (addr_p)
+ *addr_p = addr;
+ if (elf_gnu_ifunc_record_cache (name, addr))
+ return 1;
+ }
+
+ return 0;
+}
+
+/* Try to find the target resolved function entry address of a STT_GNU_IFUNC
+ function NAME. If the address is found it is stored to *ADDR_P (if ADDR_P
+ is not NULL) and the function returns 1. It returns 0 otherwise.
+
+ Both the elf_objfile_gnu_ifunc_cache_data hash table and
+ SYMBOL_GOT_PLT_SUFFIX locations are searched by this function. */
+
+static int
+elf_gnu_ifunc_resolve_name (const char *name, CORE_ADDR *addr_p)
+{
+ if (elf_gnu_ifunc_resolve_by_cache (name, addr_p))
+ return 1;
+
+ if (elf_gnu_ifunc_resolve_by_got (name, addr_p))
+ return 1;
+
+ return 0;
+}
+
+/* Call STT_GNU_IFUNC - a function returning addresss of a real function to
+ call. PC is theSTT_GNU_IFUNC resolving function entry. The value returned
+ is the entry point of the resolved STT_GNU_IFUNC target function to call.
+ */
+
+static CORE_ADDR
+elf_gnu_ifunc_resolve_addr (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+ const char *name_at_pc;
+ CORE_ADDR start_at_pc, address;
+ struct type *func_func_type = builtin_type (gdbarch)->builtin_func_func;
+ struct value *function, *address_val;
+
+ /* Try first any non-intrusive methods without an inferior call. */
+
+ if (find_pc_partial_function (pc, &name_at_pc, &start_at_pc, NULL)
+ && start_at_pc == pc)
+ {
+ if (elf_gnu_ifunc_resolve_name (name_at_pc, &address))
+ return address;
+ }
+ else
+ name_at_pc = NULL;
+
+ function = allocate_value (func_func_type);
+ set_value_address (function, pc);
+
+ /* STT_GNU_IFUNC resolver functions have no parameters. FUNCTION is the
+ function entry address. ADDRESS may be a function descriptor. */
+
+ address_val = call_function_by_hand (function, 0, NULL);
+ address = value_as_address (address_val);
+ address = gdbarch_convert_from_func_ptr_addr (gdbarch, address,
+ ¤t_target);
+
+ if (name_at_pc)
+ elf_gnu_ifunc_record_cache (name_at_pc, address);
+
+ return address;
+}
+
+/* Handle inferior hit of bp_gnu_ifunc_resolver, see its definition. */
+
+static void
+elf_gnu_ifunc_resolver_stop (struct breakpoint *b)
+{
+ struct breakpoint *b_return;
+ struct frame_info *prev_frame = get_prev_frame (get_current_frame ());
+ struct frame_id prev_frame_id = get_stack_frame_id (prev_frame);
+ CORE_ADDR prev_pc = get_frame_pc (prev_frame);
+ int thread_id = pid_to_thread_id (inferior_ptid);
+
+ gdb_assert (b->type == bp_gnu_ifunc_resolver);
+
+ for (b_return = b->related_breakpoint; b_return != b;
+ b_return = b_return->related_breakpoint)
+ {
+ gdb_assert (b_return->type == bp_gnu_ifunc_resolver_return);
+ gdb_assert (b_return->loc != NULL && b_return->loc->next == NULL);
+ gdb_assert (frame_id_p (b_return->frame_id));
+
+ if (b_return->thread == thread_id
+ && b_return->loc->requested_address == prev_pc
+ && frame_id_eq (b_return->frame_id, prev_frame_id))
+ break;
+ }
+
+ if (b_return == b)
+ {
+ struct symtab_and_line sal;
+
+ /* No need to call find_pc_line for symbols resolving as this is only
+ a helper breakpointer never shown to the user. */
+
+ init_sal (&sal);
+ sal.pspace = current_inferior ()->pspace;
+ sal.pc = prev_pc;
+ sal.section = find_pc_overlay (sal.pc);
+ sal.explicit_pc = 1;
+ b_return = set_momentary_breakpoint (get_frame_arch (prev_frame), sal,
+ prev_frame_id,
+ bp_gnu_ifunc_resolver_return);
+
+ /* set_momentary_breakpoint invalidates PREV_FRAME. */
+ prev_frame = NULL;
+
+ /* Add new b_return to the ring list b->related_breakpoint. */
+ gdb_assert (b_return->related_breakpoint == b_return);
+ b_return->related_breakpoint = b->related_breakpoint;
+ b->related_breakpoint = b_return;
+ }
+}
+
+/* Handle inferior hit of bp_gnu_ifunc_resolver_return, see its definition. */
+
+static void
+elf_gnu_ifunc_resolver_return_stop (struct breakpoint *b)
+{
+ struct gdbarch *gdbarch = get_frame_arch (get_current_frame ());
+ struct type *func_func_type = builtin_type (gdbarch)->builtin_func_func;
+ struct type *value_type = TYPE_TARGET_TYPE (func_func_type);
+ struct regcache *regcache = get_thread_regcache (inferior_ptid);
+ struct value *func_func;
+ struct value *value;
+ CORE_ADDR resolved_address, resolved_pc;
+ struct symtab_and_line sal;
+ struct symtabs_and_lines sals, sals_end;
+
+ gdb_assert (b->type == bp_gnu_ifunc_resolver_return);
+
+ while (b->related_breakpoint != b)
+ {
+ struct breakpoint *b_next = b->related_breakpoint;
+
+ switch (b->type)
+ {
+ case bp_gnu_ifunc_resolver:
+ break;
+ case bp_gnu_ifunc_resolver_return:
+ delete_breakpoint (b);
+ break;
+ default:
+ internal_error (__FILE__, __LINE__,
+ _("handle_inferior_event: Invalid "
+ "gnu-indirect-function breakpoint type %d"),
+ (int) b->type);
+ }
+ b = b_next;
+ }
+ gdb_assert (b->type == bp_gnu_ifunc_resolver);
+ gdb_assert (b->loc->next == NULL);
+
+ func_func = allocate_value (func_func_type);
+ set_value_address (func_func, b->loc->related_address);
+
+ value = allocate_value (value_type);
+ gdbarch_return_value (gdbarch, func_func, value_type, regcache,
+ value_contents_raw (value), NULL);
+ resolved_address = value_as_address (value);
+ resolved_pc = gdbarch_convert_from_func_ptr_addr (gdbarch,
+ resolved_address,
+ ¤t_target);
+
+ gdb_assert (current_program_space == b->pspace || b->pspace == NULL);
+ elf_gnu_ifunc_record_cache (b->addr_string, resolved_pc);
+
+ sal = find_pc_line (resolved_pc, 0);
+ sals.nelts = 1;
+ sals.sals = &sal;
+ sals_end.nelts = 0;
+
+ b->type = bp_breakpoint;
+ update_breakpoint_locations (b, sals, sals_end);
+}
/* Locate NT_GNU_BUILD_ID from ABFD and return its content. */
-static struct build_id *
+static const struct elf_build_id *
build_id_bfd_get (bfd *abfd)
{
- struct build_id *retval;
-
if (!bfd_check_format (abfd, bfd_object)
|| bfd_get_flavour (abfd) != bfd_target_elf_flavour
|| elf_tdata (abfd)->build_id == NULL)
return NULL;
- retval = xmalloc (sizeof *retval - 1 + elf_tdata (abfd)->build_id_size);
- retval->size = elf_tdata (abfd)->build_id_size;
- memcpy (retval->data, elf_tdata (abfd)->build_id, retval->size);
-
- return retval;
+ return elf_tdata (abfd)->build_id;
}
/* Return if FILENAME has NT_GNU_BUILD_ID matching the CHECK value. */
static int
-build_id_verify (const char *filename, struct build_id *check)
+build_id_verify (const char *filename, const struct elf_build_id *check)
{
bfd *abfd;
- struct build_id *found = NULL;
+ const struct elf_build_id *found;
int retval = 0;
/* We expect to be silent on the non-existing files. */
- abfd = bfd_open_maybe_remote (filename);
+ abfd = gdb_bfd_open_maybe_remote (filename);
if (abfd == NULL)
return 0;
else
retval = 1;
- gdb_bfd_close_or_warn (abfd);
-
- xfree (found);
+ gdb_bfd_unref (abfd);
return retval;
}
static char *
-build_id_to_debug_filename (struct build_id *build_id)
+build_id_to_debug_filename (const struct elf_build_id *build_id)
{
char *link, *debugdir, *retval = NULL;
+ VEC (char_ptr) *debugdir_vec;
+ struct cleanup *back_to;
+ int ix;
/* DEBUG_FILE_DIRECTORY/.build-id/ab/cdef */
link = alloca (strlen (debug_file_directory) + (sizeof "/.build-id/" - 1) + 1
/* Keep backward compatibility so that DEBUG_FILE_DIRECTORY being "" will
cause "/.build-id/..." lookups. */
- debugdir = debug_file_directory;
- do
+ debugdir_vec = dirnames_to_char_ptr_vec (debug_file_directory);
+ back_to = make_cleanup_free_char_ptr_vec (debugdir_vec);
+
+ for (ix = 0; VEC_iterate (char_ptr, debugdir_vec, ix, debugdir); ++ix)
{
- char *s, *debugdir_end;
- gdb_byte *data = build_id->data;
+ size_t debugdir_len = strlen (debugdir);
+ const gdb_byte *data = build_id->data;
size_t size = build_id->size;
+ char *s;
- while (*debugdir == DIRNAME_SEPARATOR)
- debugdir++;
-
- debugdir_end = strchr (debugdir, DIRNAME_SEPARATOR);
- if (debugdir_end == NULL)
- debugdir_end = &debugdir[strlen (debugdir)];
-
- memcpy (link, debugdir, debugdir_end - debugdir);
- s = &link[debugdir_end - debugdir];
+ memcpy (link, debugdir, debugdir_len);
+ s = &link[debugdir_len];
s += sprintf (s, "/.build-id/");
if (size > 0)
{
if (retval != NULL)
break;
-
- debugdir = debugdir_end;
}
- while (*debugdir != 0);
+ do_cleanups (back_to);
return retval;
}
static char *
find_separate_debug_file_by_buildid (struct objfile *objfile)
{
- struct build_id *build_id;
+ const struct elf_build_id *build_id;
build_id = build_id_bfd_get (objfile->obfd);
if (build_id != NULL)
char *build_id_name;
build_id_name = build_id_to_debug_filename (build_id);
- xfree (build_id);
/* Prevent looping on a stripped .debug file. */
- if (build_id_name != NULL && strcmp (build_id_name, objfile->name) == 0)
+ if (build_id_name != NULL
+ && filename_cmp (build_id_name, objfile_name (objfile)) == 0)
{
warning (_("\"%s\": separate debug info file has no debug info"),
build_id_name);
}
/* Scan and build partial symbols for a symbol file.
- We have been initialized by a call to elf_symfile_init, which
+ We have been initialized by a call to elf_symfile_init, which
currently does nothing.
SECTION_OFFSETS is a set of offsets to apply to relocate the symbols
static void
elf_symfile_read (struct objfile *objfile, int symfile_flags)
{
- bfd *abfd = objfile->obfd;
+ bfd *synth_abfd, *abfd = objfile->obfd;
struct elfinfo ei;
struct cleanup *back_to;
long symcount = 0, dynsymcount = 0, synthcount, storage_needed;
asymbol **symbol_table = NULL, **dyn_symbol_table = NULL;
asymbol *synthsyms;
+ struct dbx_symfile_info *dbx;
+
+ if (symtab_create_debug)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "Reading minimal symbols of objfile %s ...\n",
+ objfile_name (objfile));
+ }
init_minimal_symbol_collection ();
back_to = make_cleanup_discard_minimal_symbols ();
memset ((char *) &ei, 0, sizeof (ei));
/* Allocate struct to keep track of the symfile. */
- objfile->deprecated_sym_stab_info = (struct dbx_symfile_info *)
- xmalloc (sizeof (struct dbx_symfile_info));
- memset ((char *) objfile->deprecated_sym_stab_info,
- 0, sizeof (struct dbx_symfile_info));
+ dbx = XCNEW (struct dbx_symfile_info);
+ set_objfile_data (objfile, dbx_objfile_data_key, dbx);
make_cleanup (free_elfinfo, (void *) objfile);
/* Process the normal ELF symbol table first. This may write some
- chain of info into the dbx_symfile_info in
- objfile->deprecated_sym_stab_info, which can later be used by
- elfstab_offset_sections. */
+ chain of info into the dbx_symfile_info of the objfile, which can
+ later be used by elfstab_offset_sections. */
storage_needed = bfd_get_symtab_upper_bound (objfile->obfd);
if (storage_needed < 0)
bfd_errmsg (bfd_get_error ()));
elf_symtab_read (objfile, ST_DYNAMIC, dynsymcount, dyn_symbol_table, 0);
+
+ elf_rel_plt_read (objfile, dyn_symbol_table);
}
+ /* Contrary to binutils --strip-debug/--only-keep-debug the strip command from
+ elfutils (eu-strip) moves even the .symtab section into the .debug file.
+
+ bfd_get_synthetic_symtab on ppc64 for each function descriptor ELF symbol
+ 'name' creates a new BSF_SYNTHETIC ELF symbol '.name' with its code
+ address. But with eu-strip files bfd_get_synthetic_symtab would fail to
+ read the code address from .opd while it reads the .symtab section from
+ a separate debug info file as the .opd section is SHT_NOBITS there.
+
+ With SYNTH_ABFD the .opd section will be read from the original
+ backlinked binary where it is valid. */
+
+ if (objfile->separate_debug_objfile_backlink)
+ synth_abfd = objfile->separate_debug_objfile_backlink->obfd;
+ else
+ synth_abfd = abfd;
+
/* Add synthetic symbols - for instance, names for any PLT entries. */
- synthcount = bfd_get_synthetic_symtab (abfd, symcount, symbol_table,
+ synthcount = bfd_get_synthetic_symtab (synth_abfd, symcount, symbol_table,
dynsymcount, dyn_symbol_table,
&synthsyms);
if (synthcount > 0)
install_minimal_symbols (objfile);
do_cleanups (back_to);
+ if (symtab_create_debug)
+ fprintf_unfiltered (gdb_stdlog, "Done reading minimal symbols.\n");
+
/* Now process debugging information, which is contained in
special ELF sections. */
bfd_section_size (abfd, str_sect));
}
- if (dwarf2_has_info (objfile))
+ if (dwarf2_has_info (objfile, NULL))
{
- if (dwarf2_initialize_objfile (objfile))
+ /* elf_sym_fns_gdb_index cannot handle simultaneous non-DWARF debug
+ information present in OBJFILE. If there is such debug info present
+ never use .gdb_index. */
+
+ if (!objfile_has_partial_symbols (objfile)
+ && dwarf2_initialize_objfile (objfile))
objfile->sf = &elf_sym_fns_gdb_index;
else
{
/* If the file has its own symbol tables it has no separate debug
info. `.dynsym'/`.symtab' go to MSYMBOLS, `.debug_info' goes to
SYMTABS/PSYMTABS. `.gnu_debuglink' may no longer be present with
- `.note.gnu.build-id'. */
- else if (!objfile_has_partial_symbols (objfile))
+ `.note.gnu.build-id'.
+
+ .gnu_debugdata is !objfile_has_partial_symbols because it contains only
+ .symtab, not .debug_* section. But if we already added .gnu_debugdata as
+ an objfile via find_separate_debug_file_in_section there was no separate
+ debug info available. Therefore do not attempt to search for another one,
+ objfile->separate_debug_objfile->separate_debug_objfile GDB guarantees to
+ be NULL and we would possibly violate it. */
+
+ else if (!objfile_has_partial_symbols (objfile)
+ && objfile->separate_debug_objfile == NULL
+ && objfile->separate_debug_objfile_backlink == NULL)
{
char *debugfile;
if (debugfile)
{
+ struct cleanup *cleanup = make_cleanup (xfree, debugfile);
bfd *abfd = symfile_bfd_open (debugfile);
- symbol_file_add_separate (abfd, symfile_flags, objfile);
- xfree (debugfile);
+ make_cleanup_bfd_unref (abfd);
+ symbol_file_add_separate (abfd, debugfile, symfile_flags, objfile);
+ do_cleanups (cleanup);
}
}
}
static void
read_psyms (struct objfile *objfile)
{
- if (dwarf2_has_info (objfile))
+ if (dwarf2_has_info (objfile, NULL))
dwarf2_build_psymtabs (objfile);
}
-/* This cleans up the objfile's deprecated_sym_stab_info pointer, and
- the chain of stab_section_info's, that might be dangling from
- it. */
+/* This cleans up the objfile's dbx symfile info, and the chain of
+ stab_section_info's, that might be dangling from it. */
static void
free_elfinfo (void *objp)
{
struct objfile *objfile = (struct objfile *) objp;
- struct dbx_symfile_info *dbxinfo = objfile->deprecated_sym_stab_info;
+ struct dbx_symfile_info *dbxinfo = DBX_SYMFILE_INFO (objfile);
struct stab_section_info *ssi, *nssi;
ssi = dbxinfo->stab_section_info;
static void
elf_symfile_finish (struct objfile *objfile)
{
- if (objfile->deprecated_sym_stab_info != NULL)
- {
- xfree (objfile->deprecated_sym_stab_info);
- }
-
dwarf2_free_objfile (objfile);
}
elfstab_offset_sections (struct objfile *objfile, struct partial_symtab *pst)
{
const char *filename = pst->filename;
- struct dbx_symfile_info *dbx = objfile->deprecated_sym_stab_info;
+ struct dbx_symfile_info *dbx = DBX_SYMFILE_INFO (objfile);
struct stab_section_info *maybe = dbx->stab_section_info;
struct stab_section_info *questionable = 0;
int i;
- char *p;
/* The ELF symbol info doesn't include path names, so strip the path
(if any) from the psymtab filename. */
- while (0 != (p = strchr (filename, '/')))
- filename = p + 1;
+ filename = lbasename (filename);
/* FIXME: This linear search could speed up significantly
if it was chained in the right order to match how we search it,
for (; maybe; maybe = maybe->next)
{
if (filename[0] == maybe->filename[0]
- && strcmp (filename, maybe->filename) == 0)
+ && filename_cmp (filename, maybe->filename) == 0)
{
/* We found a match. But there might be several source files
(from different directories) with the same name. */
/* Found it! Allocate a new psymtab struct, and fill it in. */
maybe->found++;
pst->section_offsets = (struct section_offsets *)
- obstack_alloc (&objfile->objfile_obstack,
+ obstack_alloc (&objfile->objfile_obstack,
SIZEOF_N_SECTION_OFFSETS (objfile->num_sections));
for (i = 0; i < maybe->num_sections; i++)
(pst->section_offsets)->offsets[i] = maybe->sections[i];
complaint (&symfile_complaints,
_("elf/stab section information missing for %s"), filename);
}
+
+/* Implementation of `sym_get_probes', as documented in symfile.h. */
+
+static VEC (probe_p) *
+elf_get_probes (struct objfile *objfile)
+{
+ VEC (probe_p) *probes_per_objfile;
+
+ /* Have we parsed this objfile's probes already? */
+ probes_per_objfile = objfile_data (objfile, probe_key);
+
+ if (!probes_per_objfile)
+ {
+ int ix;
+ const struct probe_ops *probe_ops;
+
+ /* Here we try to gather information about all types of probes from the
+ objfile. */
+ for (ix = 0; VEC_iterate (probe_ops_cp, all_probe_ops, ix, probe_ops);
+ ix++)
+ probe_ops->get_probes (&probes_per_objfile, objfile);
+
+ if (probes_per_objfile == NULL)
+ {
+ VEC_reserve (probe_p, probes_per_objfile, 1);
+ gdb_assert (probes_per_objfile != NULL);
+ }
+
+ set_objfile_data (objfile, probe_key, probes_per_objfile);
+ }
+
+ return probes_per_objfile;
+}
+
+/* Implementation of `sym_get_probe_argument_count', as documented in
+ symfile.h. */
+
+static unsigned
+elf_get_probe_argument_count (struct probe *probe)
+{
+ return probe->pops->get_probe_argument_count (probe);
+}
+
+/* Implementation of `sym_can_evaluate_probe_arguments', as documented in
+ symfile.h. */
+
+static int
+elf_can_evaluate_probe_arguments (struct probe *probe)
+{
+ return probe->pops->can_evaluate_probe_arguments (probe);
+}
+
+/* Implementation of `sym_evaluate_probe_argument', as documented in
+ symfile.h. */
+
+static struct value *
+elf_evaluate_probe_argument (struct probe *probe, unsigned n)
+{
+ return probe->pops->evaluate_probe_argument (probe, n);
+}
+
+/* Implementation of `sym_compile_to_ax', as documented in symfile.h. */
+
+static void
+elf_compile_to_ax (struct probe *probe,
+ struct agent_expr *expr,
+ struct axs_value *value,
+ unsigned n)
+{
+ probe->pops->compile_to_ax (probe, expr, value, n);
+}
+
+/* Implementation of `sym_relocate_probe', as documented in symfile.h. */
+
+static void
+elf_symfile_relocate_probe (struct objfile *objfile,
+ const struct section_offsets *new_offsets,
+ const struct section_offsets *delta)
+{
+ int ix;
+ VEC (probe_p) *probes = objfile_data (objfile, probe_key);
+ struct probe *probe;
+
+ for (ix = 0; VEC_iterate (probe_p, probes, ix, probe); ix++)
+ probe->pops->relocate (probe, ANOFFSET (delta, SECT_OFF_TEXT (objfile)));
+}
+
+/* Helper function used to free the space allocated for storing SystemTap
+ probe information. */
+
+static void
+probe_key_free (struct objfile *objfile, void *d)
+{
+ int ix;
+ VEC (probe_p) *probes = d;
+ struct probe *probe;
+
+ for (ix = 0; VEC_iterate (probe_p, probes, ix, probe); ix++)
+ probe->pops->destroy (probe);
+
+ VEC_free (probe_p, probes);
+}
+
\f
+
+/* Implementation `sym_probe_fns', as documented in symfile.h. */
+
+static const struct sym_probe_fns elf_probe_fns =
+{
+ elf_get_probes, /* sym_get_probes */
+ elf_get_probe_argument_count, /* sym_get_probe_argument_count */
+ elf_can_evaluate_probe_arguments, /* sym_can_evaluate_probe_arguments */
+ elf_evaluate_probe_argument, /* sym_evaluate_probe_argument */
+ elf_compile_to_ax, /* sym_compile_to_ax */
+ elf_symfile_relocate_probe, /* sym_relocate_probe */
+};
+
/* Register that we are able to handle ELF object file formats. */
static const struct sym_fns elf_sym_fns =
elf_symfile_segments, /* Get segment information from a file. */
NULL,
default_symfile_relocate, /* Relocate a debug section. */
+ &elf_probe_fns, /* sym_probe_fns */
&psym_functions
};
elf_symfile_segments, /* Get segment information from a file. */
NULL,
default_symfile_relocate, /* Relocate a debug section. */
+ &elf_probe_fns, /* sym_probe_fns */
&psym_functions
};
elf_symfile_segments, /* Get segment information from a file. */
NULL,
default_symfile_relocate, /* Relocate a debug section. */
+ &elf_probe_fns, /* sym_probe_fns */
&dwarf2_gdb_index_functions
};
+/* STT_GNU_IFUNC resolver vector to be installed to gnu_ifunc_fns_p. */
+
+static const struct gnu_ifunc_fns elf_gnu_ifunc_fns =
+{
+ elf_gnu_ifunc_resolve_addr,
+ elf_gnu_ifunc_resolve_name,
+ elf_gnu_ifunc_resolver_stop,
+ elf_gnu_ifunc_resolver_return_stop
+};
+
void
_initialize_elfread (void)
{
+ probe_key = register_objfile_data_with_cleanup (NULL, probe_key_free);
add_symtab_fns (&elf_sym_fns);
+
+ elf_objfile_gnu_ifunc_cache_data = register_objfile_data ();
+ gnu_ifunc_fns_p = &elf_gnu_ifunc_fns;
}
projects / deliverable / binutils-gdb.git / blobdiff