/* Read ELF (Executable and Linking Format) object files for GDB.
- Copyright 1991, 92, 93, 94, 95, 96, 1998 Free Software Foundation, Inc.
+
+ Copyright (C) 1991-2015 Free Software Foundation, Inc.
+
Written by Fred Fish at Cygnus Support.
This file is part of GDB.
This program 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 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "bfd.h"
-#include "gdb_string.h"
#include "elf-bfd.h"
+#include "elf/common.h"
+#include "elf/internal.h"
#include "elf/mips.h"
#include "symtab.h"
#include "symfile.h"
#include "gdb-stabs.h"
#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"
+#include "build-id.h"
+#include "location.h"
extern void _initialize_elfread (void);
+/* Forward declarations. */
+extern const struct sym_fns elf_sym_fns_gdb_index;
+extern const struct sym_fns elf_sym_fns_lazy_psyms;
+
/* The struct elfinfo is available only during ELF symbol table and
psymtab reading. It is destroyed at the completion of psymtab-reading.
It's local to elf_symfile_read. */
struct elfinfo
{
- file_ptr dboffset; /* Offset to dwarf debug section */
- unsigned int dbsize; /* Size of dwarf debug section */
- file_ptr lnoffset; /* Offset to dwarf line number section */
- unsigned int lnsize; /* Size of dwarf line number section */
asection *stabsect; /* Section pointer for .stab section */
- asection *stabindexsect; /* Section pointer for .stab.index section */
asection *mdebugsect; /* Section pointer for .mdebug section */
};
-/* Various things we might complain about... */
+/* Per-BFD data for probe info. */
-struct complaint section_info_complaint =
-{"elf/stab section information %s without a preceding file symbol", 0, 0};
+static const struct bfd_data *probe_key = NULL;
-struct complaint section_info_dup_complaint =
-{"duplicated elf/stab section information for %s", 0, 0};
+/* 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. */
-struct complaint stab_info_mismatch_complaint =
-{"elf/stab section information missing for %s", 0, 0};
+#define SYMBOL_GOT_PLT_SUFFIX "@got.plt"
-struct complaint stab_info_questionable_complaint =
-{"elf/stab section information questionable for %s", 0, 0};
+/* Locate the segments in ABFD. */
-static void elf_symfile_init (struct objfile *);
-
-static void elf_new_init (struct objfile *);
+static struct symfile_segment_data *
+elf_symfile_segments (bfd *abfd)
+{
+ Elf_Internal_Phdr *phdrs, **segments;
+ long phdrs_size;
+ int num_phdrs, num_segments, num_sections, i;
+ asection *sect;
+ struct symfile_segment_data *data;
+
+ phdrs_size = bfd_get_elf_phdr_upper_bound (abfd);
+ if (phdrs_size == -1)
+ return NULL;
+
+ phdrs = alloca (phdrs_size);
+ num_phdrs = bfd_get_elf_phdrs (abfd, phdrs);
+ if (num_phdrs == -1)
+ return NULL;
+
+ num_segments = 0;
+ segments = XALLOCAVEC (Elf_Internal_Phdr *, num_phdrs);
+ for (i = 0; i < num_phdrs; i++)
+ if (phdrs[i].p_type == PT_LOAD)
+ segments[num_segments++] = &phdrs[i];
+
+ if (num_segments == 0)
+ return NULL;
+
+ data = XCNEW (struct symfile_segment_data);
+ data->num_segments = num_segments;
+ data->segment_bases = XCNEWVEC (CORE_ADDR, num_segments);
+ data->segment_sizes = XCNEWVEC (CORE_ADDR, num_segments);
+
+ for (i = 0; i < num_segments; i++)
+ {
+ data->segment_bases[i] = segments[i]->p_vaddr;
+ data->segment_sizes[i] = segments[i]->p_memsz;
+ }
-static void elf_symfile_read (struct objfile *, int);
+ num_sections = bfd_count_sections (abfd);
+ data->segment_info = XCNEWVEC (int, num_sections);
-static void elf_symfile_finish (struct objfile *);
+ for (i = 0, sect = abfd->sections; sect != NULL; i++, sect = sect->next)
+ {
+ int j;
+ CORE_ADDR vma;
-static void elf_symtab_read (struct objfile *, int);
+ if ((bfd_get_section_flags (abfd, sect) & SEC_ALLOC) == 0)
+ continue;
-static void free_elfinfo (void *);
+ vma = bfd_get_section_vma (abfd, sect);
-static struct minimal_symbol *record_minimal_symbol_and_info (char *,
- CORE_ADDR,
- enum
- minimal_symbol_type,
- char *,
- asection *
- bfd_section,
- struct objfile
- *);
+ for (j = 0; j < num_segments; j++)
+ if (segments[j]->p_memsz > 0
+ && vma >= segments[j]->p_vaddr
+ && (vma - segments[j]->p_vaddr) < segments[j]->p_memsz)
+ {
+ data->segment_info[i] = j + 1;
+ break;
+ }
+
+ /* We should have found a segment for every non-empty section.
+ If we haven't, we will not relocate this section by any
+ offsets we apply to the segments. As an exception, do not
+ warn about SHT_NOBITS sections; in normal ELF execution
+ environments, SHT_NOBITS means zero-initialized and belongs
+ in a segment, but in no-OS environments some tools (e.g. ARM
+ RealView) use SHT_NOBITS for uninitialized data. Since it is
+ uninitialized, it doesn't need a program header. Such
+ 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 section \"%s\" outside of ELF segments"),
+ bfd_section_name (abfd, sect));
+ }
-static void elf_locate_sections (bfd *, asection *, void *);
+ return data;
+}
/* We are called once per section from elf_symfile_read. We
need to examine each section we are passed, check to see
FIXME: The section names should not be hardwired strings (what
should they be? I don't think most object file formats have enough
- section flags to specify what kind of debug section it is
+ section flags to specify what kind of debug section it is.
-kingdon). */
static void
-elf_locate_sections (bfd *ignore_abfd, asection *sectp, PTR eip)
+elf_locate_sections (bfd *ignore_abfd, asection *sectp, void *eip)
{
- register struct elfinfo *ei;
+ struct elfinfo *ei;
ei = (struct elfinfo *) eip;
- if (STREQ (sectp->name, ".debug"))
- {
- ei->dboffset = sectp->filepos;
- ei->dbsize = bfd_get_section_size_before_reloc (sectp);
- }
- else if (STREQ (sectp->name, ".line"))
- {
- ei->lnoffset = sectp->filepos;
- ei->lnsize = bfd_get_section_size_before_reloc (sectp);
- }
- else if (STREQ (sectp->name, ".stab"))
+ if (strcmp (sectp->name, ".stab") == 0)
{
ei->stabsect = sectp;
}
- else if (STREQ (sectp->name, ".stab.index"))
- {
- ei->stabindexsect = sectp;
- }
- else if (STREQ (sectp->name, ".mdebug"))
+ else if (strcmp (sectp->name, ".mdebug") == 0)
{
ei->mdebugsect = sectp;
}
}
-#if 0 /* Currently unused */
-
-char *
-elf_interpreter (bfd *abfd)
-{
- sec_ptr interp_sec;
- unsigned size;
- char *interp = NULL;
-
- interp_sec = bfd_get_section_by_name (abfd, ".interp");
- if (interp_sec)
- {
- size = bfd_section_size (abfd, interp_sec);
- interp = alloca (size);
- if (bfd_get_section_contents (abfd, interp_sec, interp, (file_ptr) 0,
- size))
- {
- interp = savestring (interp, size - 1);
- }
- else
- {
- interp = NULL;
- }
- }
- return (interp);
-}
-
-#endif
-
static struct minimal_symbol *
-record_minimal_symbol_and_info (char *name, CORE_ADDR address,
- enum minimal_symbol_type ms_type, char *info, /* FIXME, is this really char *? */
- asection *bfd_section, struct objfile *objfile)
+record_minimal_symbol (const char *name, int name_len, int copy_name,
+ CORE_ADDR address,
+ enum minimal_symbol_type ms_type,
+ asection *bfd_section, struct objfile *objfile)
{
-#ifdef SMASH_TEXT_ADDRESS
- if (ms_type == mst_text || ms_type == mst_file_text)
- SMASH_TEXT_ADDRESS (address);
-#endif
-
- return prim_record_minimal_symbol_and_info
- (name, address, ms_type, info, bfd_section->index, bfd_section, objfile);
-}
-
-/*
-
- LOCAL FUNCTION
+ struct gdbarch *gdbarch = get_objfile_arch (objfile);
- elf_symtab_read -- read the symbol table of an ELF file
+ if (ms_type == mst_text || ms_type == mst_file_text
+ || ms_type == mst_text_gnu_ifunc)
+ address = gdbarch_addr_bits_remove (gdbarch, address);
- SYNOPSIS
-
- void elf_symtab_read (struct objfile *objfile, int dynamic)
+ return prim_record_minimal_symbol_full (name, name_len, copy_name, address,
+ ms_type,
+ gdb_bfd_section_index (objfile->obfd,
+ bfd_section),
+ objfile);
+}
- DESCRIPTION
+/* Read the symbol table of an ELF file.
- Given an objfile and a flag that specifies whether or not the objfile
- is for an executable or not (may be shared library for example), add
- all the global function and data symbols to the minimal symbol table.
+ Given an objfile, a symbol table, and a flag indicating whether the
+ symbol table contains regular, dynamic, or synthetic symbols, add all
+ the global function and data symbols to the minimal symbol table.
In stabs-in-ELF, as implemented by Sun, there are some local symbols
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
+#define ST_SYNTHETIC 2
static void
-elf_symtab_read (struct objfile *objfile, int dynamic)
+elf_symtab_read (struct objfile *objfile, int type,
+ long number_of_symbols, asymbol **symbol_table,
+ int copy_names)
{
- long storage_needed;
+ struct gdbarch *gdbarch = get_objfile_arch (objfile);
asymbol *sym;
- asymbol **symbol_table;
- long number_of_symbols;
long i;
- int index;
- struct cleanup *back_to;
CORE_ADDR symaddr;
CORE_ADDR offset;
enum minimal_symbol_type ms_type;
- /* If sectinfo is nonNULL, it contains section info that should end up
- filed in the objfile. */
- struct stab_section_info *sectinfo = NULL;
- /* If filesym is nonzero, it points to a file symbol, but we haven't
- seen any section info for it yet. */
- asymbol *filesym = 0;
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- /* Name of filesym, as saved on the symbol_obstack. */
- char *filesymname = obsavestring ("", 0, &objfile->symbol_obstack);
-#endif
- struct dbx_symfile_info *dbx = objfile->sym_stab_info;
- unsigned long size;
+ /* Name of the last file symbol. This is either a constant string or is
+ saved on 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);
+ int elf_make_msymbol_special_p
+ = gdbarch_elf_make_msymbol_special_p (gdbarch);
- if (dynamic)
+ for (i = 0; i < number_of_symbols; i++)
{
- storage_needed = bfd_get_dynamic_symtab_upper_bound (objfile->obfd);
+ sym = symbol_table[i];
+ if (sym->name == NULL || *sym->name == '\0')
+ {
+ /* Skip names that don't exist (shouldn't happen), or names
+ that are null strings (may happen). */
+ continue;
+ }
- /* Nothing to be done if there is no dynamic symtab. */
- if (storage_needed < 0)
- return;
- }
- else
- {
- storage_needed = bfd_get_symtab_upper_bound (objfile->obfd);
- if (storage_needed < 0)
- error ("Can't read symbols from %s: %s", bfd_get_filename (objfile->obfd),
- bfd_errmsg (bfd_get_error ()));
- }
- if (storage_needed > 0)
- {
- symbol_table = (asymbol **) xmalloc (storage_needed);
- back_to = make_cleanup (free, symbol_table);
- if (dynamic)
- number_of_symbols = bfd_canonicalize_dynamic_symtab (objfile->obfd,
- symbol_table);
- else
- number_of_symbols = bfd_canonicalize_symtab (objfile->obfd, symbol_table);
- if (number_of_symbols < 0)
- error ("Can't read symbols from %s: %s", bfd_get_filename (objfile->obfd),
- bfd_errmsg (bfd_get_error ()));
+ /* Skip "special" symbols, e.g. ARM mapping symbols. These are
+ symbols which do not correspond to objects in the symbol table,
+ but have some other target-specific meaning. */
+ if (bfd_is_target_special_symbol (objfile->obfd, sym))
+ {
+ if (gdbarch_record_special_symbol_p (gdbarch))
+ gdbarch_record_special_symbol (gdbarch, objfile, sym);
+ continue;
+ }
- for (i = 0; i < number_of_symbols; i++)
+ offset = ANOFFSET (objfile->section_offsets,
+ gdb_bfd_section_index (objfile->obfd, sym->section));
+ if (type == ST_DYNAMIC
+ && sym->section == bfd_und_section_ptr
+ && (sym->flags & BSF_FUNCTION))
{
- sym = symbol_table[i];
- if (sym->name == NULL || *sym->name == '\0')
- {
- /* Skip names that don't exist (shouldn't happen), or names
- that are null strings (may happen). */
- continue;
- }
+ struct minimal_symbol *msym;
+ bfd *abfd = objfile->obfd;
+ asection *sect;
+
+ /* Symbol is a reference to a function defined in
+ a shared library.
+ If its value is non zero then it is usually the address
+ of the corresponding entry in the procedure linkage table,
+ plus the desired section offset.
+ If its value is zero then the dynamic linker has to resolve
+ the symbol. We are unable to find any meaningful address
+ for this symbol in the executable file, so we skip it. */
+ symaddr = sym->value;
+ if (symaddr == 0)
+ continue;
- offset = ANOFFSET (objfile->section_offsets, sym->section->index);
- if (dynamic
- && sym->section == &bfd_und_section
- && (sym->flags & BSF_FUNCTION))
+ /* sym->section is the undefined section. However, we want to
+ record the section where the PLT stub resides with the
+ minimal symbol. Search the section table for the one that
+ covers the stub's address. */
+ for (sect = abfd->sections; sect != NULL; sect = sect->next)
{
- struct minimal_symbol *msym;
-
- /* Symbol is a reference to a function defined in
- a shared library.
- If its value is non zero then it is usually the address
- of the corresponding entry in the procedure linkage table,
- plus the desired section offset.
- If its value is zero then the dynamic linker has to resolve
- the symbol. We are unable to find any meaningful address
- for this symbol in the executable file, so we skip it. */
- symaddr = sym->value;
- if (symaddr == 0)
+ if ((bfd_get_section_flags (abfd, sect) & SEC_ALLOC) == 0)
continue;
- symaddr += offset;
- msym = record_minimal_symbol_and_info
- ((char *) sym->name, symaddr,
- mst_solib_trampoline, NULL, sym->section, objfile);
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- if (msym != NULL)
- msym->filename = filesymname;
-#endif
- continue;
+
+ if (symaddr >= bfd_get_section_vma (abfd, sect)
+ && symaddr < bfd_get_section_vma (abfd, sect)
+ + bfd_get_section_size (sect))
+ break;
}
+ if (!sect)
+ continue;
- /* If it is a nonstripped executable, do not enter dynamic
- symbols, as the dynamic symbol table is usually a subset
- of the main symbol table. */
- if (dynamic && !stripped)
+ /* 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 (!startswith (sect->name, ".plt")
+ && bfd_get_section_by_name (abfd, ".plt") != NULL)
continue;
- if (sym->flags & BSF_FILE)
+
+ msym = record_minimal_symbol
+ (sym->name, strlen (sym->name), copy_names,
+ symaddr, mst_solib_trampoline, sect, objfile);
+ if (msym != NULL)
{
- /* STT_FILE debugging symbol that helps stabs-in-elf debugging.
- Chain any old one onto the objfile; remember new sym. */
- if (sectinfo != NULL)
+ msym->filename = filesymname;
+ if (elf_make_msymbol_special_p)
+ gdbarch_elf_make_msymbol_special (gdbarch, sym, msym);
+ }
+ continue;
+ }
+
+ /* If it is a nonstripped executable, do not enter dynamic
+ symbols, as the dynamic symbol table is usually a subset
+ of the main symbol table. */
+ if (type == ST_DYNAMIC && !stripped)
+ continue;
+ if (sym->flags & BSF_FILE)
+ {
+ filesymname = bcache (sym->name, strlen (sym->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
+ | BSF_GNU_UNIQUE))
+ {
+ struct minimal_symbol *msym;
+
+ /* Select global/local/weak symbols. Note that bfd puts abs
+ symbols in their own section, so all symbols we are
+ interested in will have a section. */
+ /* Bfd symbols are section relative. */
+ symaddr = sym->value + sym->section->vma;
+ /* 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_ptr)
+ {
+ /* This is a hack to get the minimal symbol type
+ right for Irix 5, which has absolute addresses
+ with special section indices for dynamic symbols.
+
+ NOTE: uweigand-20071112: Synthetic symbols do not
+ have an ELF-private part, so do not touch those. */
+ unsigned int shndx = type == ST_SYNTHETIC ? 0 :
+ ((elf_symbol_type *) sym)->internal_elf_sym.st_shndx;
+
+ switch (shndx)
{
- sectinfo->next = dbx->stab_section_info;
- dbx->stab_section_info = sectinfo;
- sectinfo = NULL;
+ case SHN_MIPS_TEXT:
+ ms_type = mst_text;
+ break;
+ case SHN_MIPS_DATA:
+ ms_type = mst_data;
+ break;
+ case SHN_MIPS_ACOMMON:
+ ms_type = mst_bss;
+ break;
+ default:
+ ms_type = mst_abs;
+ }
+
+ /* If it is an Irix dynamic symbol, skip section name
+ symbols, relocate all others by section offset. */
+ if (ms_type != mst_abs)
+ {
+ if (sym->name[0] == '.')
+ continue;
}
- filesym = sym;
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- filesymname =
- obsavestring ((char *) filesym->name, strlen (filesym->name),
- &objfile->symbol_obstack);
-#endif
}
- else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK))
+ else if (sym->section->flags & SEC_CODE)
{
- struct minimal_symbol *msym;
-
- /* Select global/local/weak symbols. Note that bfd puts abs
- symbols in their own section, so all symbols we are
- interested in will have a section. */
- /* Bfd symbols are section relative. */
- symaddr = sym->value + sym->section->vma;
- /* Relocate all non-absolute symbols by the section offset. */
- if (sym->section != &bfd_abs_section)
+ if (sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_GNU_UNIQUE))
{
- symaddr += offset;
+ if (sym->flags & BSF_GNU_INDIRECT_FUNCTION)
+ ms_type = mst_text_gnu_ifunc;
+ else
+ ms_type = mst_text;
}
- /* 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)
+ /* 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] == '$'
+ && sym->name[1] == 'L'))
+ /* Looks like a compiler-generated label. Skip
+ it. The assembler should be skipping these (to
+ keep executables small), but apparently with
+ gcc on the (deleted) delta m88k SVR4, it loses.
+ So to have us check too should be harmless (but
+ I encourage people to fix this in the assembler
+ instead of adding checks here). */
+ continue;
+ else
{
- /* This is a hack to get the minimal symbol type
- right for Irix 5, which has absolute addresses
- with special section indices for dynamic symbols. */
- unsigned short shndx =
- ((elf_symbol_type *) sym)->internal_elf_sym.st_shndx;
-
- switch (shndx)
- {
- case SHN_MIPS_TEXT:
- ms_type = mst_text;
- break;
- case SHN_MIPS_DATA:
- ms_type = mst_data;
- break;
- case SHN_MIPS_ACOMMON:
- ms_type = mst_bss;
- break;
- default:
- ms_type = mst_abs;
- }
-
- /* If it is an Irix dynamic symbol, skip section name
- symbols, relocate all others by section offset. */
- if (ms_type != mst_abs)
- {
- if (sym->name[0] == '.')
- continue;
- symaddr += offset;
- }
+ ms_type = mst_file_text;
}
- else if (sym->section->flags & SEC_CODE)
+ }
+ else if (sym->section->flags & SEC_ALLOC)
+ {
+ if (sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_GNU_UNIQUE))
{
- if (sym->flags & BSF_GLOBAL)
+ if (sym->section->flags & SEC_LOAD)
{
- ms_type = mst_text;
- }
- else if ((sym->name[0] == '.' && sym->name[1] == 'L')
- || ((sym->flags & BSF_LOCAL)
- && sym->name[0] == '$'
- && sym->name[1] == 'L'))
- /* Looks like a compiler-generated label. Skip it.
- The assembler should be skipping these (to keep
- executables small), but apparently with gcc on the
- delta m88k SVR4, it loses. So to have us check too
- should be harmless (but I encourage people to fix this
- in the assembler instead of adding checks here). */
- continue;
-#ifdef HARRIS_TARGET
- else if (sym->name[0] == '.' && sym->name[1] == '.')
- {
- /* Looks like a Harris compiler generated label for the
- purpose of marking instructions that are relevant to
- DWARF dies. The assembler can't get rid of these
- because they are relocatable addresses that the
- linker needs to resolve. */
- continue;
+ ms_type = mst_data;
}
-#endif
else
{
- ms_type = mst_file_text;
+ ms_type = mst_bss;
}
}
- else if (sym->section->flags & SEC_ALLOC)
+ else if (sym->flags & BSF_LOCAL)
{
- if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
- {
- if (sym->section->flags & SEC_LOAD)
- {
- ms_type = mst_data;
- }
- else
- {
- ms_type = mst_bss;
- }
- }
- else if (sym->flags & BSF_LOCAL)
+ if (sym->section->flags & SEC_LOAD)
{
- /* Named Local variable in a Data section. Check its
- name for stabs-in-elf. The STREQ macro checks the
- first character inline, so we only actually do a
- strcmp function call on names that start with 'B'
- or 'D' */
- index = SECT_OFF_MAX;
- if (STREQ ("Bbss.bss", sym->name))
- {
- index = SECT_OFF_BSS (objfile);
- }
- else if (STREQ ("Ddata.data", sym->name))
- {
- index = SECT_OFF_DATA (objfile);
- }
- else if (STREQ ("Drodata.rodata", sym->name))
- {
- index = SECT_OFF_RODATA (objfile);
- }
- if (index != SECT_OFF_MAX)
- {
- /* Found a special local symbol. Allocate a
- sectinfo, if needed, and fill it in. */
- if (sectinfo == NULL)
- {
- sectinfo = (struct stab_section_info *)
- xmmalloc (objfile->md, sizeof (*sectinfo));
- memset ((PTR) sectinfo, 0, sizeof (*sectinfo));
- if (filesym == NULL)
- {
- complain (§ion_info_complaint,
- sym->name);
- }
- else
- {
- sectinfo->filename =
- (char *) filesym->name;
- }
- }
- if (index != -1)
- {
- if (sectinfo->sections[index] != 0)
- {
- complain (§ion_info_dup_complaint,
- sectinfo->filename);
- }
- }
- else
- internal_error ("Section index uninitialized.");
- /* Bfd symbols are section relative. */
- symaddr = sym->value + sym->section->vma;
- /* Relocate non-absolute symbols by the section offset. */
- if (sym->section != &bfd_abs_section)
- {
- symaddr += offset;
- }
- if (index != -1)
- sectinfo->sections[index] = symaddr;
- else
- internal_error ("Section index uninitialized.");
- /* The special local symbols don't go in the
- minimal symbol table, so ignore this one. */
- continue;
- }
- /* Not a special stabs-in-elf symbol, do regular
- symbol processing. */
- if (sym->section->flags & SEC_LOAD)
- {
- ms_type = mst_file_data;
- }
- else
- {
- ms_type = mst_file_bss;
- }
+ ms_type = mst_file_data;
}
else
{
- ms_type = mst_unknown;
+ ms_type = mst_file_bss;
}
}
else
{
- /* FIXME: Solaris2 shared libraries include lots of
- 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; */
- continue; /* Skip this symbol. */
+ ms_type = mst_unknown;
+ }
+ }
+ else
+ {
+ /* FIXME: Solaris2 shared libraries include lots of
+ 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; */
+ continue; /* Skip this symbol. */
+ }
+ msym = record_minimal_symbol
+ (sym->name, strlen (sym->name), copy_names, symaddr,
+ ms_type, sym->section, objfile);
+
+ if (msym)
+ {
+ /* NOTE: uweigand-20071112: A synthetic symbol does not have an
+ ELF-private part. */
+ if (type != ST_SYNTHETIC)
+ {
+ /* 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);
+ }
+
+ msym->filename = filesymname;
+ if (elf_make_msymbol_special_p)
+ 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
+ trying to find the target. */
+ if (msym && ms_type == mst_text && type == ST_SYNTHETIC)
+ {
+ int len = strlen (sym->name);
+
+ if (len > 4 && strcmp (sym->name + len - 4, "@plt") == 0)
+ {
+ struct minimal_symbol *mtramp;
+
+ mtramp = record_minimal_symbol (sym->name, len - 4, 1,
+ symaddr,
+ mst_solib_trampoline,
+ sym->section, objfile);
+ if (mtramp)
+ {
+ SET_MSYMBOL_SIZE (mtramp, MSYMBOL_SIZE (msym));
+ mtramp->created_by_gdb = 1;
+ mtramp->filename = filesymname;
+ if (elf_make_msymbol_special_p)
+ gdbarch_elf_make_msymbol_special (gdbarch,
+ sym, mtramp);
+ }
}
- /* Pass symbol size field in via BFD. FIXME!!! */
- size = ((elf_symbol_type *) sym)->internal_elf_sym.st_size;
- msym = record_minimal_symbol_and_info
- ((char *) sym->name, symaddr,
- ms_type, (PTR) size, sym->section, objfile);
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- if (msym != NULL)
- msym->filename = filesymname;
-#endif
-#ifdef ELF_MAKE_MSYMBOL_SPECIAL
- ELF_MAKE_MSYMBOL_SPECIAL (sym, msym);
-#endif
}
}
- do_cleanups (back_to);
}
}
-/* Scan and build partial symbols for a symbol file.
- We have been initialized by a call to elf_symfile_init, which
- currently does nothing.
+/* 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)
+ {
+ /* For platforms where there is no separate .got.plt. */
+ got_plt = bfd_get_section_by_name (obfd, ".got");
+ 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);
+}
+
+/* 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 (BMSYMBOL_VALUE_ADDRESS (msym) != addr)
+ return 0;
+ /* minimal symbols have always SYMBOL_OBJ_SECTION non-NULL. */
+ sect = MSYMBOL_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 bound_minimal_symbol msym;
+
+ msym = lookup_minimal_symbol (name_got_plt, NULL, objfile);
+ if (msym.minsym == NULL)
+ continue;
+ if (MSYMBOL_TYPE (msym.minsym) != mst_slot_got_plt)
+ continue;
+ pointer_address = BMSYMBOL_VALUE_ADDRESS (msym);
+
+ plt = bfd_get_section_by_name (obfd, ".plt");
+ if (plt == NULL)
+ continue;
+
+ if (MSYMBOL_SIZE (msym.minsym) != 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);
+ addr = gdbarch_addr_bits_remove (gdbarch, addr);
+
+ 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);
+ address = gdbarch_addr_bits_remove (gdbarch, address);
+
+ 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);
+ resolved_pc = gdbarch_addr_bits_remove (gdbarch, resolved_pc);
+
+ gdb_assert (current_program_space == b->pspace || b->pspace == NULL);
+ elf_gnu_ifunc_record_cache (event_location_to_string (b->location),
+ 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);
+}
+
+/* A helper function for elf_symfile_read that reads the minimal
+ symbols. */
+
+static void
+elf_read_minimal_symbols (struct objfile *objfile, int symfile_flags,
+ const struct elfinfo *ei)
+{
+ bfd *synth_abfd, *abfd = objfile->obfd;
+ 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));
+ }
+
+ /* If we already have minsyms, then we can skip some work here.
+ However, if there were stabs or mdebug sections, we go ahead and
+ redo all the work anyway, because the psym readers for those
+ kinds of debuginfo need extra information found here. This can
+ go away once all types of symbols are in the per-BFD object. */
+ if (objfile->per_bfd->minsyms_read
+ && ei->stabsect == NULL
+ && ei->mdebugsect == NULL)
+ {
+ if (symtab_create_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "... minimal symbols previously read\n");
+ return;
+ }
+
+ init_minimal_symbol_collection ();
+ back_to = make_cleanup_discard_minimal_symbols ();
+
+ /* Allocate struct to keep track of the symfile. */
+ dbx = XCNEW (struct dbx_symfile_info);
+ set_objfile_data (objfile, dbx_objfile_data_key, dbx);
+
+ /* Process the normal ELF symbol table first. */
+
+ storage_needed = bfd_get_symtab_upper_bound (objfile->obfd);
+ if (storage_needed < 0)
+ error (_("Can't read symbols from %s: %s"),
+ bfd_get_filename (objfile->obfd),
+ bfd_errmsg (bfd_get_error ()));
+
+ if (storage_needed > 0)
+ {
+ /* Memory gets permanently referenced from ABFD after
+ bfd_canonicalize_symtab so it must not get freed before ABFD gets. */
+
+ symbol_table = bfd_alloc (abfd, storage_needed);
+ symcount = bfd_canonicalize_symtab (objfile->obfd, symbol_table);
+
+ if (symcount < 0)
+ error (_("Can't read symbols from %s: %s"),
+ bfd_get_filename (objfile->obfd),
+ bfd_errmsg (bfd_get_error ()));
+
+ elf_symtab_read (objfile, ST_REGULAR, symcount, symbol_table, 0);
+ }
+
+ /* Add the dynamic symbols. */
+
+ storage_needed = bfd_get_dynamic_symtab_upper_bound (objfile->obfd);
+
+ if (storage_needed > 0)
+ {
+ /* Memory gets permanently referenced from ABFD after
+ bfd_get_synthetic_symtab so it must not get freed before ABFD gets.
+ It happens only in the case when elf_slurp_reloc_table sees
+ asection->relocation NULL. Determining which section is asection is
+ done by _bfd_elf_get_synthetic_symtab which is all a bfd
+ implementation detail, though. */
+
+ dyn_symbol_table = bfd_alloc (abfd, storage_needed);
+ dynsymcount = bfd_canonicalize_dynamic_symtab (objfile->obfd,
+ dyn_symbol_table);
+
+ if (dynsymcount < 0)
+ error (_("Can't read symbols from %s: %s"),
+ bfd_get_filename (objfile->obfd),
+ bfd_errmsg (bfd_get_error ()));
+
+ elf_symtab_read (objfile, ST_DYNAMIC, dynsymcount, dyn_symbol_table, 0);
+
+ elf_rel_plt_read (objfile, dyn_symbol_table);
+ }
- SECTION_OFFSETS is a set of offsets to apply to relocate the symbols
- in each section. We simplify it down to a single offset for all
- symbols. FIXME.
+ /* Contrary to binutils --strip-debug/--only-keep-debug the strip command from
+ elfutils (eu-strip) moves even the .symtab section into the .debug file.
- MAINLINE is true if we are reading the main symbol
- table (as opposed to a shared lib or dynamically loaded 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 (synth_abfd, symcount, symbol_table,
+ dynsymcount, dyn_symbol_table,
+ &synthsyms);
+ if (synthcount > 0)
+ {
+ asymbol **synth_symbol_table;
+ long i;
+
+ make_cleanup (xfree, synthsyms);
+ synth_symbol_table = XNEWVEC (asymbol *, synthcount);
+ for (i = 0; i < synthcount; i++)
+ synth_symbol_table[i] = synthsyms + i;
+ make_cleanup (xfree, synth_symbol_table);
+ elf_symtab_read (objfile, ST_SYNTHETIC, synthcount,
+ synth_symbol_table, 1);
+ }
+
+ /* Install any minimal symbols that have been collected as the current
+ minimal symbols for this objfile. The debug readers below this point
+ should not generate new minimal symbols; if they do it's their
+ responsibility to install them. "mdebug" appears to be the only one
+ which will do this. */
+
+ install_minimal_symbols (objfile);
+ do_cleanups (back_to);
+
+ if (symtab_create_debug)
+ fprintf_unfiltered (gdb_stdlog, "Done reading minimal symbols.\n");
+}
+
+/* Scan and build partial symbols for a symbol file.
+ We have been initialized by a call to elf_symfile_init, which
+ currently does nothing.
This function only does the minimum work necessary for letting the
user "name" things symbolically; it does not read the entire symtab.
We look for sections with specific names, to tell us what debug
format to look for: FIXME!!!
- dwarf_build_psymtabs() builds psymtabs for DWARF symbols;
elfstab_build_psymtabs() handles STABS symbols;
mdebug_build_psymtabs() handles ECOFF debugging information.
capability even for files compiled without -g. */
static void
-elf_symfile_read (struct objfile *objfile, int mainline)
+elf_symfile_read (struct objfile *objfile, int symfile_flags)
{
bfd *abfd = objfile->obfd;
struct elfinfo ei;
- struct cleanup *back_to;
- CORE_ADDR offset;
-
- init_minimal_symbol_collection ();
- back_to = make_cleanup_discard_minimal_symbols ();
memset ((char *) &ei, 0, sizeof (ei));
+ bfd_map_over_sections (abfd, elf_locate_sections, (void *) & ei);
- /* Allocate struct to keep track of the symfile */
- objfile->sym_stab_info = (struct dbx_symfile_info *)
- xmmalloc (objfile->md, sizeof (struct dbx_symfile_info));
- memset ((char *) objfile->sym_stab_info, 0, sizeof (struct dbx_symfile_info));
- make_cleanup (free_elfinfo, (PTR) objfile);
-
- /* Process the normal ELF symbol table first. This may write some
- chain of info into the dbx_symfile_info in objfile->sym_stab_info,
- which can later be used by elfstab_offset_sections. */
-
- elf_symtab_read (objfile, 0);
-
- /* Add the dynamic symbols. */
-
- elf_symtab_read (objfile, 1);
-
- /* Now process debugging information, which is contained in
- special ELF sections. */
-
- /* If we are reinitializing, or if we have never loaded syms yet,
- set table to empty. MAINLINE is cleared so that *_read_psymtab
- functions do not all also re-initialize the psymbol table. */
- if (mainline)
- {
- init_psymbol_list (objfile, 0);
- mainline = 0;
- }
-
- /* We first have to find them... */
- bfd_map_over_sections (abfd, elf_locate_sections, (PTR) & ei);
+ elf_read_minimal_symbols (objfile, symfile_flags, &ei);
/* ELF debugging information is inserted into the psymtab in the
order of least informative first - most informative last. Since
and .debug_info (DWARF2) sections then .mdebug is inserted first
(searched last) and DWARF2 is inserted last (searched first). If
we don't do this then the XCOFF info is found first - for code in
- an included file XCOFF info is useless. */
+ an included file XCOFF info is useless. */
if (ei.mdebugsect)
{
/* FIXME should probably warn about a stab section without a stabstr. */
if (str_sect)
elfstab_build_psymtabs (objfile,
- mainline,
- ei.stabsect->filepos,
- bfd_section_size (abfd, ei.stabsect),
+ ei.stabsect,
str_sect->filepos,
bfd_section_size (abfd, str_sect));
}
- if (dwarf2_has_info (abfd))
+
+ if (dwarf2_has_info (objfile, NULL))
{
- /* DWARF 2 sections */
- dwarf2_build_psymtabs (objfile, mainline);
+ /* 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_set_sym_fns (objfile, &elf_sym_fns_gdb_index);
+ else
+ {
+ /* It is ok to do this even if the stabs reader made some
+ partial symbols, because OBJF_PSYMTABS_READ has not been
+ set, and so our lazy reader function will still be called
+ when needed. */
+ objfile_set_sym_fns (objfile, &elf_sym_fns_lazy_psyms);
+ }
}
- else if (ei.dboffset && ei.lnoffset)
+ /* 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'.
+
+ .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)
{
- /* DWARF sections */
- dwarf_build_psymtabs (objfile,
- mainline,
- ei.dboffset, ei.dbsize,
- ei.lnoffset, ei.lnsize);
- }
+ char *debugfile;
- /* Install any minimal symbols that have been collected as the current
- minimal symbols for this objfile. */
+ debugfile = find_separate_debug_file_by_buildid (objfile);
- install_minimal_symbols (objfile);
+ if (debugfile == NULL)
+ debugfile = find_separate_debug_file_by_debuglink (objfile);
- do_cleanups (back_to);
+ if (debugfile)
+ {
+ struct cleanup *cleanup = make_cleanup (xfree, debugfile);
+ bfd *abfd = symfile_bfd_open (debugfile);
+
+ make_cleanup_bfd_unref (abfd);
+ symbol_file_add_separate (abfd, debugfile, symfile_flags, objfile);
+ do_cleanups (cleanup);
+ }
+ }
}
-/* This cleans up the objfile's sym_stab_info pointer, and the chain of
- stab_section_info's, that might be dangling from it. */
+/* Callback to lazily read psymtabs. */
static void
-free_elfinfo (PTR objp)
+read_psyms (struct objfile *objfile)
{
- struct objfile *objfile = (struct objfile *) objp;
- struct dbx_symfile_info *dbxinfo = objfile->sym_stab_info;
- struct stab_section_info *ssi, *nssi;
-
- ssi = dbxinfo->stab_section_info;
- while (ssi)
- {
- nssi = ssi->next;
- mfree (objfile->md, ssi);
- ssi = nssi;
- }
-
- dbxinfo->stab_section_info = 0; /* Just say No mo info about this. */
+ if (dwarf2_has_info (objfile, NULL))
+ dwarf2_build_psymtabs (objfile);
}
-
/* Initialize anything that needs initializing when a completely new symbol
file is specified (not just adding some symbols from another file, e.g. a
shared library).
- We reinitialize buildsym, since we may be reading stabs from an ELF file. */
+ We reinitialize buildsym, since we may be reading stabs from an ELF
+ file. */
static void
elf_new_init (struct objfile *ignore)
/* Perform any local cleanups required when we are done with a particular
objfile. I.E, we are in the process of discarding all symbol information
for an objfile, freeing up all memory held for it, and unlinking the
- objfile struct from the global list of known objfiles. */
+ objfile struct from the global list of known objfiles. */
static void
elf_symfile_finish (struct objfile *objfile)
{
- if (objfile->sym_stab_info != NULL)
- {
- mfree (objfile->md, objfile->sym_stab_info);
- }
+ dwarf2_free_objfile (objfile);
}
-/* ELF specific initialization routine for reading symbols.
-
- It is passed a pointer to a struct sym_fns which contains, among other
- things, the BFD for the file whose symbols are being read, and a slot for
- a pointer to "private data" which we can fill with goodies.
-
- For now at least, we have nothing in particular to do, so this function is
- just a stub. */
+/* ELF specific initialization routine for reading symbols. */
static void
elf_symfile_init (struct objfile *objfile)
objfile->flags |= OBJF_REORDERED;
}
-/* When handling an ELF file that contains Sun STABS debug info,
- some of the debug info is relative to the particular chunk of the
- section that was generated in its individual .o file. E.g.
- offsets to static variables are relative to the start of the data
- segment *for that module before linking*. This information is
- painfully squirreled away in the ELF symbol table as local symbols
- with wierd names. Go get 'em when needed. */
+/* Implementation of `sym_get_probes', as documented in symfile.h. */
-void
-elfstab_offset_sections (struct objfile *objfile, struct partial_symtab *pst)
+static VEC (probe_p) *
+elf_get_probes (struct objfile *objfile)
{
- char *filename = pst->filename;
- struct dbx_symfile_info *dbx = objfile->sym_stab_info;
- 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;
-
- /* FIXME: This linear search could speed up significantly
- if it was chained in the right order to match how we search it,
- and if we unchained when we found a match. */
- for (; maybe; maybe = maybe->next)
+ VEC (probe_p) *probes_per_bfd;
+
+ /* Have we parsed this objfile's probes already? */
+ probes_per_bfd = bfd_data (objfile->obfd, probe_key);
+
+ if (!probes_per_bfd)
{
- if (filename[0] == maybe->filename[0]
- && STREQ (filename, maybe->filename))
+ 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_bfd, objfile);
+
+ if (probes_per_bfd == NULL)
{
- /* We found a match. But there might be several source files
- (from different directories) with the same name. */
- if (0 == maybe->found)
- break;
- questionable = maybe; /* Might use it later. */
+ VEC_reserve (probe_p, probes_per_bfd, 1);
+ gdb_assert (probes_per_bfd != NULL);
}
- }
- if (maybe == 0 && questionable != 0)
- {
- complain (&stab_info_questionable_complaint, filename);
- maybe = questionable;
+ set_bfd_data (objfile->obfd, probe_key, probes_per_bfd);
}
- if (maybe)
- {
- /* Found it! Allocate a new psymtab struct, and fill it in. */
- maybe->found++;
- pst->section_offsets = (struct section_offsets *)
- obstack_alloc (&objfile->psymbol_obstack, SIZEOF_SECTION_OFFSETS);
- for (i = 0; i < SECT_OFF_MAX; i++)
- (pst->section_offsets)->offsets[i] = maybe->sections[i];
- return;
- }
+ return probes_per_bfd;
+}
+
+/* Helper function used to free the space allocated for storing SystemTap
+ probe information. */
- /* We were unable to find any offsets for this file. Complain. */
- if (dbx->stab_section_info) /* If there *is* any info, */
- complain (&stab_info_mismatch_complaint, filename);
+static void
+probe_key_free (bfd *abfd, 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 */
+};
+
/* Register that we are able to handle ELF object file formats. */
-static struct sym_fns elf_sym_fns =
+static const struct sym_fns elf_sym_fns =
+{
+ elf_new_init, /* init anything gbl to entire symtab */
+ elf_symfile_init, /* read initial info, setup for sym_read() */
+ elf_symfile_read, /* read a symbol file into symtab */
+ NULL, /* sym_read_psymbols */
+ elf_symfile_finish, /* finished with file, cleanup */
+ default_symfile_offsets, /* Translate ext. to int. relocation */
+ 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
+};
+
+/* The same as elf_sym_fns, but not registered and lazily reads
+ psymbols. */
+
+const struct sym_fns elf_sym_fns_lazy_psyms =
+{
+ elf_new_init, /* init anything gbl to entire symtab */
+ elf_symfile_init, /* read initial info, setup for sym_read() */
+ elf_symfile_read, /* read a symbol file into symtab */
+ read_psyms, /* sym_read_psymbols */
+ elf_symfile_finish, /* finished with file, cleanup */
+ default_symfile_offsets, /* Translate ext. to int. relocation */
+ 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
+};
+
+/* The same as elf_sym_fns, but not registered and uses the
+ DWARF-specific GNU index rather than psymtab. */
+const struct sym_fns elf_sym_fns_gdb_index =
{
- bfd_target_elf_flavour,
- elf_new_init, /* sym_new_init: init anything gbl to entire symtab */
- elf_symfile_init, /* sym_init: read initial info, setup for sym_read() */
- elf_symfile_read, /* sym_read: read a symbol file into symtab */
- elf_symfile_finish, /* sym_finish: finished with file, cleanup */
- default_symfile_offsets, /* sym_offsets: Translate ext. to int. relocation */
- NULL /* next: pointer to next struct sym_fns */
+ elf_new_init, /* init anything gbl to entire symab */
+ elf_symfile_init, /* read initial info, setup for sym_red() */
+ elf_symfile_read, /* read a symbol file into symtab */
+ NULL, /* sym_read_psymbols */
+ elf_symfile_finish, /* finished with file, cleanup */
+ default_symfile_offsets, /* Translate ext. to int. relocatin */
+ 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)
{
- add_symtab_fns (&elf_sym_fns);
+ probe_key = register_bfd_data_with_cleanup (NULL, probe_key_free);
+ add_symtab_fns (bfd_target_elf_flavour, &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