1489 lines
44 KiB
C
1489 lines
44 KiB
C
/* GDB routines for manipulating the minimal symbol tables.
|
||
Copyright (C) 1992-2019 Free Software Foundation, Inc.
|
||
Contributed by Cygnus Support, using pieces from other GDB modules.
|
||
|
||
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 3 of the License, or
|
||
(at your option) any later version.
|
||
|
||
This program is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
GNU General Public License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with this program. If not, see <http://www.gnu.org/licenses/>. */
|
||
|
||
|
||
/* This file contains support routines for creating, manipulating, and
|
||
destroying minimal symbol tables.
|
||
|
||
Minimal symbol tables are used to hold some very basic information about
|
||
all defined global symbols (text, data, bss, abs, etc). The only two
|
||
required pieces of information are the symbol's name and the address
|
||
associated with that symbol.
|
||
|
||
In many cases, even if a file was compiled with no special options for
|
||
debugging at all, as long as was not stripped it will contain sufficient
|
||
information to build useful minimal symbol tables using this structure.
|
||
|
||
Even when a file contains enough debugging information to build a full
|
||
symbol table, these minimal symbols are still useful for quickly mapping
|
||
between names and addresses, and vice versa. They are also sometimes used
|
||
to figure out what full symbol table entries need to be read in. */
|
||
|
||
|
||
#include "defs.h"
|
||
#include <ctype.h>
|
||
#include "symtab.h"
|
||
#include "bfd.h"
|
||
#include "filenames.h"
|
||
#include "symfile.h"
|
||
#include "objfiles.h"
|
||
#include "demangle.h"
|
||
#include "value.h"
|
||
#include "cp-abi.h"
|
||
#include "target.h"
|
||
#include "cp-support.h"
|
||
#include "language.h"
|
||
#include "cli/cli-utils.h"
|
||
#include "common/symbol.h"
|
||
#include <algorithm>
|
||
#include "safe-ctype.h"
|
||
|
||
/* See minsyms.h. */
|
||
|
||
bool
|
||
msymbol_is_function (struct objfile *objfile, minimal_symbol *minsym,
|
||
CORE_ADDR *func_address_p)
|
||
{
|
||
CORE_ADDR msym_addr = MSYMBOL_VALUE_ADDRESS (objfile, minsym);
|
||
|
||
switch (minsym->type)
|
||
{
|
||
case mst_slot_got_plt:
|
||
case mst_data:
|
||
case mst_bss:
|
||
case mst_abs:
|
||
case mst_file_data:
|
||
case mst_file_bss:
|
||
case mst_data_gnu_ifunc:
|
||
{
|
||
struct gdbarch *gdbarch = get_objfile_arch (objfile);
|
||
CORE_ADDR pc
|
||
= gdbarch_convert_from_func_ptr_addr (gdbarch, msym_addr,
|
||
current_top_target ());
|
||
if (pc != msym_addr)
|
||
{
|
||
if (func_address_p != NULL)
|
||
*func_address_p = pc;
|
||
return true;
|
||
}
|
||
return false;
|
||
}
|
||
default:
|
||
if (func_address_p != NULL)
|
||
*func_address_p = msym_addr;
|
||
return true;
|
||
}
|
||
}
|
||
|
||
/* Accumulate the minimal symbols for each objfile in bunches of BUNCH_SIZE.
|
||
At the end, copy them all into one newly allocated array. */
|
||
|
||
#define BUNCH_SIZE 127
|
||
|
||
struct msym_bunch
|
||
{
|
||
struct msym_bunch *next;
|
||
struct minimal_symbol contents[BUNCH_SIZE];
|
||
};
|
||
|
||
/* See minsyms.h. */
|
||
|
||
unsigned int
|
||
msymbol_hash_iw (const char *string)
|
||
{
|
||
unsigned int hash = 0;
|
||
|
||
while (*string && *string != '(')
|
||
{
|
||
string = skip_spaces (string);
|
||
if (*string && *string != '(')
|
||
{
|
||
hash = SYMBOL_HASH_NEXT (hash, *string);
|
||
++string;
|
||
}
|
||
}
|
||
return hash;
|
||
}
|
||
|
||
/* See minsyms.h. */
|
||
|
||
unsigned int
|
||
msymbol_hash (const char *string)
|
||
{
|
||
unsigned int hash = 0;
|
||
|
||
for (; *string; ++string)
|
||
hash = SYMBOL_HASH_NEXT (hash, *string);
|
||
return hash;
|
||
}
|
||
|
||
/* Add the minimal symbol SYM to an objfile's minsym hash table, TABLE. */
|
||
static void
|
||
add_minsym_to_hash_table (struct minimal_symbol *sym,
|
||
struct minimal_symbol **table)
|
||
{
|
||
if (sym->hash_next == NULL)
|
||
{
|
||
unsigned int hash
|
||
= msymbol_hash (MSYMBOL_LINKAGE_NAME (sym)) % MINIMAL_SYMBOL_HASH_SIZE;
|
||
|
||
sym->hash_next = table[hash];
|
||
table[hash] = sym;
|
||
}
|
||
}
|
||
|
||
/* Add the minimal symbol SYM to an objfile's minsym demangled hash table,
|
||
TABLE. */
|
||
static void
|
||
add_minsym_to_demangled_hash_table (struct minimal_symbol *sym,
|
||
struct objfile *objfile)
|
||
{
|
||
if (sym->demangled_hash_next == NULL)
|
||
{
|
||
unsigned int hash = search_name_hash (MSYMBOL_LANGUAGE (sym),
|
||
MSYMBOL_SEARCH_NAME (sym));
|
||
|
||
objfile->per_bfd->demangled_hash_languages.set (MSYMBOL_LANGUAGE (sym));
|
||
|
||
struct minimal_symbol **table
|
||
= objfile->per_bfd->msymbol_demangled_hash;
|
||
unsigned int hash_index = hash % MINIMAL_SYMBOL_HASH_SIZE;
|
||
sym->demangled_hash_next = table[hash_index];
|
||
table[hash_index] = sym;
|
||
}
|
||
}
|
||
|
||
/* Worker object for lookup_minimal_symbol. Stores temporary results
|
||
while walking the symbol tables. */
|
||
|
||
struct found_minimal_symbols
|
||
{
|
||
/* External symbols are best. */
|
||
bound_minimal_symbol external_symbol {};
|
||
|
||
/* File-local symbols are next best. */
|
||
bound_minimal_symbol file_symbol {};
|
||
|
||
/* Symbols for shared library trampolines are next best. */
|
||
bound_minimal_symbol trampoline_symbol {};
|
||
|
||
/* Called when a symbol name matches. Check if the minsym is a
|
||
better type than what we had already found, and record it in one
|
||
of the members fields if so. Returns true if we collected the
|
||
real symbol, in which case we can stop searching. */
|
||
bool maybe_collect (const char *sfile, objfile *objf,
|
||
minimal_symbol *msymbol);
|
||
};
|
||
|
||
/* See declaration above. */
|
||
|
||
bool
|
||
found_minimal_symbols::maybe_collect (const char *sfile,
|
||
struct objfile *objfile,
|
||
minimal_symbol *msymbol)
|
||
{
|
||
switch (MSYMBOL_TYPE (msymbol))
|
||
{
|
||
case mst_file_text:
|
||
case mst_file_data:
|
||
case mst_file_bss:
|
||
if (sfile == NULL
|
||
|| filename_cmp (msymbol->filename, sfile) == 0)
|
||
{
|
||
file_symbol.minsym = msymbol;
|
||
file_symbol.objfile = objfile;
|
||
}
|
||
break;
|
||
|
||
case mst_solib_trampoline:
|
||
|
||
/* If a trampoline symbol is found, we prefer to keep
|
||
looking for the *real* symbol. If the actual symbol
|
||
is not found, then we'll use the trampoline
|
||
entry. */
|
||
if (trampoline_symbol.minsym == NULL)
|
||
{
|
||
trampoline_symbol.minsym = msymbol;
|
||
trampoline_symbol.objfile = objfile;
|
||
}
|
||
break;
|
||
|
||
case mst_unknown:
|
||
default:
|
||
external_symbol.minsym = msymbol;
|
||
external_symbol.objfile = objfile;
|
||
/* We have the real symbol. No use looking further. */
|
||
return true;
|
||
}
|
||
|
||
/* Keep looking. */
|
||
return false;
|
||
}
|
||
|
||
/* Walk the mangled name hash table, and pass each symbol whose name
|
||
matches LOOKUP_NAME according to NAMECMP to FOUND. */
|
||
|
||
static void
|
||
lookup_minimal_symbol_mangled (const char *lookup_name,
|
||
const char *sfile,
|
||
struct objfile *objfile,
|
||
struct minimal_symbol **table,
|
||
unsigned int hash,
|
||
int (*namecmp) (const char *, const char *),
|
||
found_minimal_symbols &found)
|
||
{
|
||
for (minimal_symbol *msymbol = table[hash];
|
||
msymbol != NULL;
|
||
msymbol = msymbol->hash_next)
|
||
{
|
||
const char *symbol_name = MSYMBOL_LINKAGE_NAME (msymbol);
|
||
|
||
if (namecmp (symbol_name, lookup_name) == 0
|
||
&& found.maybe_collect (sfile, objfile, msymbol))
|
||
return;
|
||
}
|
||
}
|
||
|
||
/* Walk the demangled name hash table, and pass each symbol whose name
|
||
matches LOOKUP_NAME according to MATCHER to FOUND. */
|
||
|
||
static void
|
||
lookup_minimal_symbol_demangled (const lookup_name_info &lookup_name,
|
||
const char *sfile,
|
||
struct objfile *objfile,
|
||
struct minimal_symbol **table,
|
||
unsigned int hash,
|
||
symbol_name_matcher_ftype *matcher,
|
||
found_minimal_symbols &found)
|
||
{
|
||
for (minimal_symbol *msymbol = table[hash];
|
||
msymbol != NULL;
|
||
msymbol = msymbol->demangled_hash_next)
|
||
{
|
||
const char *symbol_name = MSYMBOL_SEARCH_NAME (msymbol);
|
||
|
||
if (matcher (symbol_name, lookup_name, NULL)
|
||
&& found.maybe_collect (sfile, objfile, msymbol))
|
||
return;
|
||
}
|
||
}
|
||
|
||
/* Look through all the current minimal symbol tables and find the
|
||
first minimal symbol that matches NAME. If OBJF is non-NULL, limit
|
||
the search to that objfile. If SFILE is non-NULL, the only file-scope
|
||
symbols considered will be from that source file (global symbols are
|
||
still preferred). Returns a pointer to the minimal symbol that
|
||
matches, or NULL if no match is found.
|
||
|
||
Note: One instance where there may be duplicate minimal symbols with
|
||
the same name is when the symbol tables for a shared library and the
|
||
symbol tables for an executable contain global symbols with the same
|
||
names (the dynamic linker deals with the duplication).
|
||
|
||
It's also possible to have minimal symbols with different mangled
|
||
names, but identical demangled names. For example, the GNU C++ v3
|
||
ABI requires the generation of two (or perhaps three) copies of
|
||
constructor functions --- "in-charge", "not-in-charge", and
|
||
"allocate" copies; destructors may be duplicated as well.
|
||
Obviously, there must be distinct mangled names for each of these,
|
||
but the demangled names are all the same: S::S or S::~S. */
|
||
|
||
struct bound_minimal_symbol
|
||
lookup_minimal_symbol (const char *name, const char *sfile,
|
||
struct objfile *objf)
|
||
{
|
||
struct objfile *objfile;
|
||
found_minimal_symbols found;
|
||
|
||
unsigned int mangled_hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
|
||
|
||
auto *mangled_cmp
|
||
= (case_sensitivity == case_sensitive_on
|
||
? strcmp
|
||
: strcasecmp);
|
||
|
||
if (sfile != NULL)
|
||
sfile = lbasename (sfile);
|
||
|
||
lookup_name_info lookup_name (name, symbol_name_match_type::FULL);
|
||
|
||
for (objfile = object_files;
|
||
objfile != NULL && found.external_symbol.minsym == NULL;
|
||
objfile = objfile->next)
|
||
{
|
||
if (objf == NULL || objf == objfile
|
||
|| objf == objfile->separate_debug_objfile_backlink)
|
||
{
|
||
if (symbol_lookup_debug)
|
||
{
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"lookup_minimal_symbol (%s, %s, %s)\n",
|
||
name, sfile != NULL ? sfile : "NULL",
|
||
objfile_debug_name (objfile));
|
||
}
|
||
|
||
/* Do two passes: the first over the ordinary hash table,
|
||
and the second over the demangled hash table. */
|
||
lookup_minimal_symbol_mangled (name, sfile, objfile,
|
||
objfile->per_bfd->msymbol_hash,
|
||
mangled_hash, mangled_cmp, found);
|
||
|
||
/* If not found, try the demangled hash table. */
|
||
if (found.external_symbol.minsym == NULL)
|
||
{
|
||
/* Once for each language in the demangled hash names
|
||
table (usually just zero or one languages). */
|
||
for (unsigned iter = 0; iter < nr_languages; ++iter)
|
||
{
|
||
if (!objfile->per_bfd->demangled_hash_languages.test (iter))
|
||
continue;
|
||
enum language lang = (enum language) iter;
|
||
|
||
unsigned int hash
|
||
= (lookup_name.search_name_hash (lang)
|
||
% MINIMAL_SYMBOL_HASH_SIZE);
|
||
|
||
symbol_name_matcher_ftype *match
|
||
= get_symbol_name_matcher (language_def (lang),
|
||
lookup_name);
|
||
struct minimal_symbol **msymbol_demangled_hash
|
||
= objfile->per_bfd->msymbol_demangled_hash;
|
||
|
||
lookup_minimal_symbol_demangled (lookup_name, sfile, objfile,
|
||
msymbol_demangled_hash,
|
||
hash, match, found);
|
||
|
||
if (found.external_symbol.minsym != NULL)
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/* External symbols are best. */
|
||
if (found.external_symbol.minsym != NULL)
|
||
{
|
||
if (symbol_lookup_debug)
|
||
{
|
||
minimal_symbol *minsym = found.external_symbol.minsym;
|
||
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"lookup_minimal_symbol (...) = %s (external)\n",
|
||
host_address_to_string (minsym));
|
||
}
|
||
return found.external_symbol;
|
||
}
|
||
|
||
/* File-local symbols are next best. */
|
||
if (found.file_symbol.minsym != NULL)
|
||
{
|
||
if (symbol_lookup_debug)
|
||
{
|
||
minimal_symbol *minsym = found.file_symbol.minsym;
|
||
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"lookup_minimal_symbol (...) = %s (file-local)\n",
|
||
host_address_to_string (minsym));
|
||
}
|
||
return found.file_symbol;
|
||
}
|
||
|
||
/* Symbols for shared library trampolines are next best. */
|
||
if (found.trampoline_symbol.minsym != NULL)
|
||
{
|
||
if (symbol_lookup_debug)
|
||
{
|
||
minimal_symbol *minsym = found.trampoline_symbol.minsym;
|
||
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"lookup_minimal_symbol (...) = %s (trampoline)\n",
|
||
host_address_to_string (minsym));
|
||
}
|
||
|
||
return found.trampoline_symbol;
|
||
}
|
||
|
||
/* Not found. */
|
||
if (symbol_lookup_debug)
|
||
fprintf_unfiltered (gdb_stdlog, "lookup_minimal_symbol (...) = NULL\n");
|
||
return {};
|
||
}
|
||
|
||
/* See minsyms.h. */
|
||
|
||
struct bound_minimal_symbol
|
||
lookup_bound_minimal_symbol (const char *name)
|
||
{
|
||
return lookup_minimal_symbol (name, NULL, NULL);
|
||
}
|
||
|
||
/* See common/symbol.h. */
|
||
|
||
int
|
||
find_minimal_symbol_address (const char *name, CORE_ADDR *addr,
|
||
struct objfile *objfile)
|
||
{
|
||
struct bound_minimal_symbol sym
|
||
= lookup_minimal_symbol (name, NULL, objfile);
|
||
|
||
if (sym.minsym != NULL)
|
||
*addr = BMSYMBOL_VALUE_ADDRESS (sym);
|
||
|
||
return sym.minsym == NULL;
|
||
}
|
||
|
||
/* Get the lookup name form best suitable for linkage name
|
||
matching. */
|
||
|
||
static const char *
|
||
linkage_name_str (const lookup_name_info &lookup_name)
|
||
{
|
||
/* Unlike most languages (including C++), Ada uses the
|
||
encoded/linkage name as the search name recorded in symbols. So
|
||
if debugging in Ada mode, prefer the Ada-encoded name. This also
|
||
makes Ada's verbatim match syntax ("<...>") work, because
|
||
"lookup_name.name()" includes the "<>"s, while
|
||
"lookup_name.ada().lookup_name()" is the encoded name with "<>"s
|
||
stripped. */
|
||
if (current_language->la_language == language_ada)
|
||
return lookup_name.ada ().lookup_name ().c_str ();
|
||
|
||
return lookup_name.name ().c_str ();
|
||
}
|
||
|
||
/* See minsyms.h. */
|
||
|
||
void
|
||
iterate_over_minimal_symbols
|
||
(struct objfile *objf, const lookup_name_info &lookup_name,
|
||
gdb::function_view<bool (struct minimal_symbol *)> callback)
|
||
{
|
||
/* The first pass is over the ordinary hash table. */
|
||
{
|
||
const char *name = linkage_name_str (lookup_name);
|
||
unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
|
||
auto *mangled_cmp
|
||
= (case_sensitivity == case_sensitive_on
|
||
? strcmp
|
||
: strcasecmp);
|
||
|
||
for (minimal_symbol *iter = objf->per_bfd->msymbol_hash[hash];
|
||
iter != NULL;
|
||
iter = iter->hash_next)
|
||
{
|
||
if (mangled_cmp (MSYMBOL_LINKAGE_NAME (iter), name) == 0)
|
||
if (callback (iter))
|
||
return;
|
||
}
|
||
}
|
||
|
||
/* The second pass is over the demangled table. Once for each
|
||
language in the demangled hash names table (usually just zero or
|
||
one). */
|
||
for (unsigned liter = 0; liter < nr_languages; ++liter)
|
||
{
|
||
if (!objf->per_bfd->demangled_hash_languages.test (liter))
|
||
continue;
|
||
|
||
enum language lang = (enum language) liter;
|
||
const language_defn *lang_def = language_def (lang);
|
||
symbol_name_matcher_ftype *name_match
|
||
= get_symbol_name_matcher (lang_def, lookup_name);
|
||
|
||
unsigned int hash
|
||
= lookup_name.search_name_hash (lang) % MINIMAL_SYMBOL_HASH_SIZE;
|
||
for (minimal_symbol *iter = objf->per_bfd->msymbol_demangled_hash[hash];
|
||
iter != NULL;
|
||
iter = iter->demangled_hash_next)
|
||
if (name_match (MSYMBOL_SEARCH_NAME (iter), lookup_name, NULL))
|
||
if (callback (iter))
|
||
return;
|
||
}
|
||
}
|
||
|
||
/* See minsyms.h. */
|
||
|
||
struct bound_minimal_symbol
|
||
lookup_minimal_symbol_text (const char *name, struct objfile *objf)
|
||
{
|
||
struct objfile *objfile;
|
||
struct minimal_symbol *msymbol;
|
||
struct bound_minimal_symbol found_symbol = { NULL, NULL };
|
||
struct bound_minimal_symbol found_file_symbol = { NULL, NULL };
|
||
|
||
unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
|
||
|
||
for (objfile = object_files;
|
||
objfile != NULL && found_symbol.minsym == NULL;
|
||
objfile = objfile->next)
|
||
{
|
||
if (objf == NULL || objf == objfile
|
||
|| objf == objfile->separate_debug_objfile_backlink)
|
||
{
|
||
for (msymbol = objfile->per_bfd->msymbol_hash[hash];
|
||
msymbol != NULL && found_symbol.minsym == NULL;
|
||
msymbol = msymbol->hash_next)
|
||
{
|
||
if (strcmp (MSYMBOL_LINKAGE_NAME (msymbol), name) == 0 &&
|
||
(MSYMBOL_TYPE (msymbol) == mst_text
|
||
|| MSYMBOL_TYPE (msymbol) == mst_text_gnu_ifunc
|
||
|| MSYMBOL_TYPE (msymbol) == mst_file_text))
|
||
{
|
||
switch (MSYMBOL_TYPE (msymbol))
|
||
{
|
||
case mst_file_text:
|
||
found_file_symbol.minsym = msymbol;
|
||
found_file_symbol.objfile = objfile;
|
||
break;
|
||
default:
|
||
found_symbol.minsym = msymbol;
|
||
found_symbol.objfile = objfile;
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
}
|
||
/* External symbols are best. */
|
||
if (found_symbol.minsym)
|
||
return found_symbol;
|
||
|
||
/* File-local symbols are next best. */
|
||
return found_file_symbol;
|
||
}
|
||
|
||
/* See minsyms.h. */
|
||
|
||
struct minimal_symbol *
|
||
lookup_minimal_symbol_by_pc_name (CORE_ADDR pc, const char *name,
|
||
struct objfile *objf)
|
||
{
|
||
struct objfile *objfile;
|
||
struct minimal_symbol *msymbol;
|
||
|
||
unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
|
||
|
||
for (objfile = object_files;
|
||
objfile != NULL;
|
||
objfile = objfile->next)
|
||
{
|
||
if (objf == NULL || objf == objfile
|
||
|| objf == objfile->separate_debug_objfile_backlink)
|
||
{
|
||
for (msymbol = objfile->per_bfd->msymbol_hash[hash];
|
||
msymbol != NULL;
|
||
msymbol = msymbol->hash_next)
|
||
{
|
||
if (MSYMBOL_VALUE_ADDRESS (objfile, msymbol) == pc
|
||
&& strcmp (MSYMBOL_LINKAGE_NAME (msymbol), name) == 0)
|
||
return msymbol;
|
||
}
|
||
}
|
||
}
|
||
|
||
return NULL;
|
||
}
|
||
|
||
/* See minsyms.h. */
|
||
|
||
struct bound_minimal_symbol
|
||
lookup_minimal_symbol_solib_trampoline (const char *name,
|
||
struct objfile *objf)
|
||
{
|
||
struct objfile *objfile;
|
||
struct minimal_symbol *msymbol;
|
||
struct bound_minimal_symbol found_symbol = { NULL, NULL };
|
||
|
||
unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE;
|
||
|
||
for (objfile = object_files;
|
||
objfile != NULL;
|
||
objfile = objfile->next)
|
||
{
|
||
if (objf == NULL || objf == objfile
|
||
|| objf == objfile->separate_debug_objfile_backlink)
|
||
{
|
||
for (msymbol = objfile->per_bfd->msymbol_hash[hash];
|
||
msymbol != NULL;
|
||
msymbol = msymbol->hash_next)
|
||
{
|
||
if (strcmp (MSYMBOL_LINKAGE_NAME (msymbol), name) == 0 &&
|
||
MSYMBOL_TYPE (msymbol) == mst_solib_trampoline)
|
||
{
|
||
found_symbol.objfile = objfile;
|
||
found_symbol.minsym = msymbol;
|
||
return found_symbol;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
return found_symbol;
|
||
}
|
||
|
||
/* A helper function that makes *PC section-relative. This searches
|
||
the sections of OBJFILE and if *PC is in a section, it subtracts
|
||
the section offset and returns true. Otherwise it returns
|
||
false. */
|
||
|
||
static int
|
||
frob_address (struct objfile *objfile, CORE_ADDR *pc)
|
||
{
|
||
struct obj_section *iter;
|
||
|
||
ALL_OBJFILE_OSECTIONS (objfile, iter)
|
||
{
|
||
if (*pc >= obj_section_addr (iter) && *pc < obj_section_endaddr (iter))
|
||
{
|
||
*pc -= obj_section_offset (iter);
|
||
return 1;
|
||
}
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Helper for lookup_minimal_symbol_by_pc_section. Convert a
|
||
lookup_msym_prefer to a minimal_symbol_type. */
|
||
|
||
static minimal_symbol_type
|
||
msym_prefer_to_msym_type (lookup_msym_prefer prefer)
|
||
{
|
||
switch (prefer)
|
||
{
|
||
case lookup_msym_prefer::TEXT:
|
||
return mst_text;
|
||
case lookup_msym_prefer::TRAMPOLINE:
|
||
return mst_solib_trampoline;
|
||
case lookup_msym_prefer::GNU_IFUNC:
|
||
return mst_text_gnu_ifunc;
|
||
}
|
||
|
||
/* Assert here instead of in a default switch case above so that
|
||
-Wswitch warns if a new enumerator is added. */
|
||
gdb_assert_not_reached ("unhandled lookup_msym_prefer");
|
||
}
|
||
|
||
/* Search through the minimal symbol table for each objfile and find
|
||
the symbol whose address is the largest address that is still less
|
||
than or equal to PC, and matches SECTION (which is not NULL).
|
||
Returns a pointer to the minimal symbol if such a symbol is found,
|
||
or NULL if PC is not in a suitable range.
|
||
Note that we need to look through ALL the minimal symbol tables
|
||
before deciding on the symbol that comes closest to the specified PC.
|
||
This is because objfiles can overlap, for example objfile A has .text
|
||
at 0x100 and .data at 0x40000 and objfile B has .text at 0x234 and
|
||
.data at 0x40048.
|
||
|
||
If WANT_TRAMPOLINE is set, prefer mst_solib_trampoline symbols when
|
||
there are text and trampoline symbols at the same address.
|
||
Otherwise prefer mst_text symbols. */
|
||
|
||
bound_minimal_symbol
|
||
lookup_minimal_symbol_by_pc_section (CORE_ADDR pc_in, struct obj_section *section,
|
||
lookup_msym_prefer prefer)
|
||
{
|
||
int lo;
|
||
int hi;
|
||
int newobj;
|
||
struct objfile *objfile;
|
||
struct minimal_symbol *msymbol;
|
||
struct minimal_symbol *best_symbol = NULL;
|
||
struct objfile *best_objfile = NULL;
|
||
struct bound_minimal_symbol result;
|
||
|
||
if (section == NULL)
|
||
{
|
||
section = find_pc_section (pc_in);
|
||
if (section == NULL)
|
||
return {};
|
||
}
|
||
|
||
minimal_symbol_type want_type = msym_prefer_to_msym_type (prefer);
|
||
|
||
/* We can not require the symbol found to be in section, because
|
||
e.g. IRIX 6.5 mdebug relies on this code returning an absolute
|
||
symbol - but find_pc_section won't return an absolute section and
|
||
hence the code below would skip over absolute symbols. We can
|
||
still take advantage of the call to find_pc_section, though - the
|
||
object file still must match. In case we have separate debug
|
||
files, search both the file and its separate debug file. There's
|
||
no telling which one will have the minimal symbols. */
|
||
|
||
gdb_assert (section != NULL);
|
||
|
||
for (objfile = section->objfile;
|
||
objfile != NULL;
|
||
objfile = objfile_separate_debug_iterate (section->objfile, objfile))
|
||
{
|
||
CORE_ADDR pc = pc_in;
|
||
|
||
/* If this objfile has a minimal symbol table, go search it
|
||
using a binary search. */
|
||
|
||
if (objfile->per_bfd->minimal_symbol_count > 0)
|
||
{
|
||
int best_zero_sized = -1;
|
||
|
||
msymbol = objfile->per_bfd->msymbols.get ();
|
||
lo = 0;
|
||
hi = objfile->per_bfd->minimal_symbol_count - 1;
|
||
|
||
/* This code assumes that the minimal symbols are sorted by
|
||
ascending address values. If the pc value is greater than or
|
||
equal to the first symbol's address, then some symbol in this
|
||
minimal symbol table is a suitable candidate for being the
|
||
"best" symbol. This includes the last real symbol, for cases
|
||
where the pc value is larger than any address in this vector.
|
||
|
||
By iterating until the address associated with the current
|
||
hi index (the endpoint of the test interval) is less than
|
||
or equal to the desired pc value, we accomplish two things:
|
||
(1) the case where the pc value is larger than any minimal
|
||
symbol address is trivially solved, (2) the address associated
|
||
with the hi index is always the one we want when the interation
|
||
terminates. In essence, we are iterating the test interval
|
||
down until the pc value is pushed out of it from the high end.
|
||
|
||
Warning: this code is trickier than it would appear at first. */
|
||
|
||
if (frob_address (objfile, &pc)
|
||
&& pc >= MSYMBOL_VALUE_RAW_ADDRESS (&msymbol[lo]))
|
||
{
|
||
while (MSYMBOL_VALUE_RAW_ADDRESS (&msymbol[hi]) > pc)
|
||
{
|
||
/* pc is still strictly less than highest address. */
|
||
/* Note "new" will always be >= lo. */
|
||
newobj = (lo + hi) / 2;
|
||
if ((MSYMBOL_VALUE_RAW_ADDRESS (&msymbol[newobj]) >= pc)
|
||
|| (lo == newobj))
|
||
{
|
||
hi = newobj;
|
||
}
|
||
else
|
||
{
|
||
lo = newobj;
|
||
}
|
||
}
|
||
|
||
/* If we have multiple symbols at the same address, we want
|
||
hi to point to the last one. That way we can find the
|
||
right symbol if it has an index greater than hi. */
|
||
while (hi < objfile->per_bfd->minimal_symbol_count - 1
|
||
&& (MSYMBOL_VALUE_RAW_ADDRESS (&msymbol[hi])
|
||
== MSYMBOL_VALUE_RAW_ADDRESS (&msymbol[hi + 1])))
|
||
hi++;
|
||
|
||
/* Skip various undesirable symbols. */
|
||
while (hi >= 0)
|
||
{
|
||
/* Skip any absolute symbols. This is apparently
|
||
what adb and dbx do, and is needed for the CM-5.
|
||
There are two known possible problems: (1) on
|
||
ELF, apparently end, edata, etc. are absolute.
|
||
Not sure ignoring them here is a big deal, but if
|
||
we want to use them, the fix would go in
|
||
elfread.c. (2) I think shared library entry
|
||
points on the NeXT are absolute. If we want
|
||
special handling for this it probably should be
|
||
triggered by a special mst_abs_or_lib or some
|
||
such. */
|
||
|
||
if (MSYMBOL_TYPE (&msymbol[hi]) == mst_abs)
|
||
{
|
||
hi--;
|
||
continue;
|
||
}
|
||
|
||
/* If SECTION was specified, skip any symbol from
|
||
wrong section. */
|
||
if (section
|
||
/* Some types of debug info, such as COFF,
|
||
don't fill the bfd_section member, so don't
|
||
throw away symbols on those platforms. */
|
||
&& MSYMBOL_OBJ_SECTION (objfile, &msymbol[hi]) != NULL
|
||
&& (!matching_obj_sections
|
||
(MSYMBOL_OBJ_SECTION (objfile, &msymbol[hi]),
|
||
section)))
|
||
{
|
||
hi--;
|
||
continue;
|
||
}
|
||
|
||
/* If we are looking for a trampoline and this is a
|
||
text symbol, or the other way around, check the
|
||
preceding symbol too. If they are otherwise
|
||
identical prefer that one. */
|
||
if (hi > 0
|
||
&& MSYMBOL_TYPE (&msymbol[hi]) != want_type
|
||
&& MSYMBOL_TYPE (&msymbol[hi - 1]) == want_type
|
||
&& (MSYMBOL_SIZE (&msymbol[hi])
|
||
== MSYMBOL_SIZE (&msymbol[hi - 1]))
|
||
&& (MSYMBOL_VALUE_RAW_ADDRESS (&msymbol[hi])
|
||
== MSYMBOL_VALUE_RAW_ADDRESS (&msymbol[hi - 1]))
|
||
&& (MSYMBOL_OBJ_SECTION (objfile, &msymbol[hi])
|
||
== MSYMBOL_OBJ_SECTION (objfile, &msymbol[hi - 1])))
|
||
{
|
||
hi--;
|
||
continue;
|
||
}
|
||
|
||
/* If the minimal symbol has a zero size, save it
|
||
but keep scanning backwards looking for one with
|
||
a non-zero size. A zero size may mean that the
|
||
symbol isn't an object or function (e.g. a
|
||
label), or it may just mean that the size was not
|
||
specified. */
|
||
if (MSYMBOL_SIZE (&msymbol[hi]) == 0)
|
||
{
|
||
if (best_zero_sized == -1)
|
||
best_zero_sized = hi;
|
||
hi--;
|
||
continue;
|
||
}
|
||
|
||
/* If we are past the end of the current symbol, try
|
||
the previous symbol if it has a larger overlapping
|
||
size. This happens on i686-pc-linux-gnu with glibc;
|
||
the nocancel variants of system calls are inside
|
||
the cancellable variants, but both have sizes. */
|
||
if (hi > 0
|
||
&& MSYMBOL_SIZE (&msymbol[hi]) != 0
|
||
&& pc >= (MSYMBOL_VALUE_RAW_ADDRESS (&msymbol[hi])
|
||
+ MSYMBOL_SIZE (&msymbol[hi]))
|
||
&& pc < (MSYMBOL_VALUE_RAW_ADDRESS (&msymbol[hi - 1])
|
||
+ MSYMBOL_SIZE (&msymbol[hi - 1])))
|
||
{
|
||
hi--;
|
||
continue;
|
||
}
|
||
|
||
/* Otherwise, this symbol must be as good as we're going
|
||
to get. */
|
||
break;
|
||
}
|
||
|
||
/* If HI has a zero size, and best_zero_sized is set,
|
||
then we had two or more zero-sized symbols; prefer
|
||
the first one we found (which may have a higher
|
||
address). Also, if we ran off the end, be sure
|
||
to back up. */
|
||
if (best_zero_sized != -1
|
||
&& (hi < 0 || MSYMBOL_SIZE (&msymbol[hi]) == 0))
|
||
hi = best_zero_sized;
|
||
|
||
/* If the minimal symbol has a non-zero size, and this
|
||
PC appears to be outside the symbol's contents, then
|
||
refuse to use this symbol. If we found a zero-sized
|
||
symbol with an address greater than this symbol's,
|
||
use that instead. We assume that if symbols have
|
||
specified sizes, they do not overlap. */
|
||
|
||
if (hi >= 0
|
||
&& MSYMBOL_SIZE (&msymbol[hi]) != 0
|
||
&& pc >= (MSYMBOL_VALUE_RAW_ADDRESS (&msymbol[hi])
|
||
+ MSYMBOL_SIZE (&msymbol[hi])))
|
||
{
|
||
if (best_zero_sized != -1)
|
||
hi = best_zero_sized;
|
||
else
|
||
/* Go on to the next object file. */
|
||
continue;
|
||
}
|
||
|
||
/* The minimal symbol indexed by hi now is the best one in this
|
||
objfile's minimal symbol table. See if it is the best one
|
||
overall. */
|
||
|
||
if (hi >= 0
|
||
&& ((best_symbol == NULL) ||
|
||
(MSYMBOL_VALUE_RAW_ADDRESS (best_symbol) <
|
||
MSYMBOL_VALUE_RAW_ADDRESS (&msymbol[hi]))))
|
||
{
|
||
best_symbol = &msymbol[hi];
|
||
best_objfile = objfile;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
result.minsym = best_symbol;
|
||
result.objfile = best_objfile;
|
||
return result;
|
||
}
|
||
|
||
/* See minsyms.h. */
|
||
|
||
struct bound_minimal_symbol
|
||
lookup_minimal_symbol_by_pc (CORE_ADDR pc)
|
||
{
|
||
return lookup_minimal_symbol_by_pc_section (pc, NULL);
|
||
}
|
||
|
||
/* Return non-zero iff PC is in an STT_GNU_IFUNC function resolver. */
|
||
|
||
int
|
||
in_gnu_ifunc_stub (CORE_ADDR pc)
|
||
{
|
||
bound_minimal_symbol msymbol
|
||
= lookup_minimal_symbol_by_pc_section (pc, NULL,
|
||
lookup_msym_prefer::GNU_IFUNC);
|
||
return msymbol.minsym && MSYMBOL_TYPE (msymbol.minsym) == mst_text_gnu_ifunc;
|
||
}
|
||
|
||
/* See elf_gnu_ifunc_resolve_addr for its real implementation. */
|
||
|
||
static CORE_ADDR
|
||
stub_gnu_ifunc_resolve_addr (struct gdbarch *gdbarch, CORE_ADDR pc)
|
||
{
|
||
error (_("GDB cannot resolve STT_GNU_IFUNC symbol at address %s without "
|
||
"the ELF support compiled in."),
|
||
paddress (gdbarch, pc));
|
||
}
|
||
|
||
/* See elf_gnu_ifunc_resolve_name for its real implementation. */
|
||
|
||
static int
|
||
stub_gnu_ifunc_resolve_name (const char *function_name,
|
||
CORE_ADDR *function_address_p)
|
||
{
|
||
error (_("GDB cannot resolve STT_GNU_IFUNC symbol \"%s\" without "
|
||
"the ELF support compiled in."),
|
||
function_name);
|
||
}
|
||
|
||
/* See elf_gnu_ifunc_resolver_stop for its real implementation. */
|
||
|
||
static void
|
||
stub_gnu_ifunc_resolver_stop (struct breakpoint *b)
|
||
{
|
||
internal_error (__FILE__, __LINE__,
|
||
_("elf_gnu_ifunc_resolver_stop cannot be reached."));
|
||
}
|
||
|
||
/* See elf_gnu_ifunc_resolver_return_stop for its real implementation. */
|
||
|
||
static void
|
||
stub_gnu_ifunc_resolver_return_stop (struct breakpoint *b)
|
||
{
|
||
internal_error (__FILE__, __LINE__,
|
||
_("elf_gnu_ifunc_resolver_return_stop cannot be reached."));
|
||
}
|
||
|
||
/* See elf_gnu_ifunc_fns for its real implementation. */
|
||
|
||
static const struct gnu_ifunc_fns stub_gnu_ifunc_fns =
|
||
{
|
||
stub_gnu_ifunc_resolve_addr,
|
||
stub_gnu_ifunc_resolve_name,
|
||
stub_gnu_ifunc_resolver_stop,
|
||
stub_gnu_ifunc_resolver_return_stop,
|
||
};
|
||
|
||
/* A placeholder for &elf_gnu_ifunc_fns. */
|
||
|
||
const struct gnu_ifunc_fns *gnu_ifunc_fns_p = &stub_gnu_ifunc_fns;
|
||
|
||
|
||
|
||
/* Return leading symbol character for a BFD. If BFD is NULL,
|
||
return the leading symbol character from the main objfile. */
|
||
|
||
static int
|
||
get_symbol_leading_char (bfd *abfd)
|
||
{
|
||
if (abfd != NULL)
|
||
return bfd_get_symbol_leading_char (abfd);
|
||
if (symfile_objfile != NULL && symfile_objfile->obfd != NULL)
|
||
return bfd_get_symbol_leading_char (symfile_objfile->obfd);
|
||
return 0;
|
||
}
|
||
|
||
/* See minsyms.h. */
|
||
|
||
minimal_symbol_reader::minimal_symbol_reader (struct objfile *obj)
|
||
: m_objfile (obj),
|
||
m_msym_bunch (NULL),
|
||
/* Note that presetting m_msym_bunch_index to BUNCH_SIZE causes the
|
||
first call to save a minimal symbol to allocate the memory for
|
||
the first bunch. */
|
||
m_msym_bunch_index (BUNCH_SIZE),
|
||
m_msym_count (0)
|
||
{
|
||
}
|
||
|
||
/* Discard the currently collected minimal symbols, if any. If we wish
|
||
to save them for later use, we must have already copied them somewhere
|
||
else before calling this function. */
|
||
|
||
minimal_symbol_reader::~minimal_symbol_reader ()
|
||
{
|
||
struct msym_bunch *next;
|
||
|
||
while (m_msym_bunch != NULL)
|
||
{
|
||
next = m_msym_bunch->next;
|
||
xfree (m_msym_bunch);
|
||
m_msym_bunch = next;
|
||
}
|
||
}
|
||
|
||
/* See minsyms.h. */
|
||
|
||
void
|
||
minimal_symbol_reader::record (const char *name, CORE_ADDR address,
|
||
enum minimal_symbol_type ms_type)
|
||
{
|
||
int section;
|
||
|
||
switch (ms_type)
|
||
{
|
||
case mst_text:
|
||
case mst_text_gnu_ifunc:
|
||
case mst_file_text:
|
||
case mst_solib_trampoline:
|
||
section = SECT_OFF_TEXT (m_objfile);
|
||
break;
|
||
case mst_data:
|
||
case mst_data_gnu_ifunc:
|
||
case mst_file_data:
|
||
section = SECT_OFF_DATA (m_objfile);
|
||
break;
|
||
case mst_bss:
|
||
case mst_file_bss:
|
||
section = SECT_OFF_BSS (m_objfile);
|
||
break;
|
||
default:
|
||
section = -1;
|
||
}
|
||
|
||
record_with_info (name, address, ms_type, section);
|
||
}
|
||
|
||
/* Convert an enumerator of type minimal_symbol_type to its string
|
||
representation. */
|
||
|
||
static const char *
|
||
mst_str (minimal_symbol_type t)
|
||
{
|
||
#define MST_TO_STR(x) case x: return #x;
|
||
switch (t)
|
||
{
|
||
MST_TO_STR (mst_unknown);
|
||
MST_TO_STR (mst_text);
|
||
MST_TO_STR (mst_text_gnu_ifunc);
|
||
MST_TO_STR (mst_slot_got_plt);
|
||
MST_TO_STR (mst_data);
|
||
MST_TO_STR (mst_bss);
|
||
MST_TO_STR (mst_abs);
|
||
MST_TO_STR (mst_solib_trampoline);
|
||
MST_TO_STR (mst_file_text);
|
||
MST_TO_STR (mst_file_data);
|
||
MST_TO_STR (mst_file_bss);
|
||
|
||
default:
|
||
return "mst_???";
|
||
}
|
||
#undef MST_TO_STR
|
||
}
|
||
|
||
/* See minsyms.h. */
|
||
|
||
struct minimal_symbol *
|
||
minimal_symbol_reader::record_full (const char *name, int name_len,
|
||
bool copy_name, CORE_ADDR address,
|
||
enum minimal_symbol_type ms_type,
|
||
int section)
|
||
{
|
||
struct msym_bunch *newobj;
|
||
struct minimal_symbol *msymbol;
|
||
|
||
/* Don't put gcc_compiled, __gnu_compiled_cplus, and friends into
|
||
the minimal symbols, because if there is also another symbol
|
||
at the same address (e.g. the first function of the file),
|
||
lookup_minimal_symbol_by_pc would have no way of getting the
|
||
right one. */
|
||
if (ms_type == mst_file_text && name[0] == 'g'
|
||
&& (strcmp (name, GCC_COMPILED_FLAG_SYMBOL) == 0
|
||
|| strcmp (name, GCC2_COMPILED_FLAG_SYMBOL) == 0))
|
||
return (NULL);
|
||
|
||
/* It's safe to strip the leading char here once, since the name
|
||
is also stored stripped in the minimal symbol table. */
|
||
if (name[0] == get_symbol_leading_char (m_objfile->obfd))
|
||
{
|
||
++name;
|
||
--name_len;
|
||
}
|
||
|
||
if (ms_type == mst_file_text && startswith (name, "__gnu_compiled"))
|
||
return (NULL);
|
||
|
||
if (symtab_create_debug >= 2)
|
||
printf_unfiltered ("Recording minsym: %-21s %18s %4d %s\n",
|
||
mst_str (ms_type), hex_string (address), section, name);
|
||
|
||
if (m_msym_bunch_index == BUNCH_SIZE)
|
||
{
|
||
newobj = XCNEW (struct msym_bunch);
|
||
m_msym_bunch_index = 0;
|
||
newobj->next = m_msym_bunch;
|
||
m_msym_bunch = newobj;
|
||
}
|
||
msymbol = &m_msym_bunch->contents[m_msym_bunch_index];
|
||
symbol_set_language (msymbol, language_auto,
|
||
&m_objfile->per_bfd->storage_obstack);
|
||
symbol_set_names (msymbol, name, name_len, copy_name, m_objfile->per_bfd);
|
||
|
||
SET_MSYMBOL_VALUE_ADDRESS (msymbol, address);
|
||
MSYMBOL_SECTION (msymbol) = section;
|
||
|
||
MSYMBOL_TYPE (msymbol) = ms_type;
|
||
|
||
/* If we already read minimal symbols for this objfile, then don't
|
||
ever allocate a new one. */
|
||
if (!m_objfile->per_bfd->minsyms_read)
|
||
{
|
||
m_msym_bunch_index++;
|
||
m_objfile->per_bfd->n_minsyms++;
|
||
}
|
||
m_msym_count++;
|
||
return msymbol;
|
||
}
|
||
|
||
/* Compare two minimal symbols by address and return a signed result based
|
||
on unsigned comparisons, so that we sort into unsigned numeric order.
|
||
Within groups with the same address, sort by name. */
|
||
|
||
static int
|
||
compare_minimal_symbols (const void *fn1p, const void *fn2p)
|
||
{
|
||
const struct minimal_symbol *fn1;
|
||
const struct minimal_symbol *fn2;
|
||
|
||
fn1 = (const struct minimal_symbol *) fn1p;
|
||
fn2 = (const struct minimal_symbol *) fn2p;
|
||
|
||
if (MSYMBOL_VALUE_RAW_ADDRESS (fn1) < MSYMBOL_VALUE_RAW_ADDRESS (fn2))
|
||
{
|
||
return (-1); /* addr 1 is less than addr 2. */
|
||
}
|
||
else if (MSYMBOL_VALUE_RAW_ADDRESS (fn1) > MSYMBOL_VALUE_RAW_ADDRESS (fn2))
|
||
{
|
||
return (1); /* addr 1 is greater than addr 2. */
|
||
}
|
||
else
|
||
/* addrs are equal: sort by name */
|
||
{
|
||
const char *name1 = MSYMBOL_LINKAGE_NAME (fn1);
|
||
const char *name2 = MSYMBOL_LINKAGE_NAME (fn2);
|
||
|
||
if (name1 && name2) /* both have names */
|
||
return strcmp (name1, name2);
|
||
else if (name2)
|
||
return 1; /* fn1 has no name, so it is "less". */
|
||
else if (name1) /* fn2 has no name, so it is "less". */
|
||
return -1;
|
||
else
|
||
return (0); /* Neither has a name, so they're equal. */
|
||
}
|
||
}
|
||
|
||
/* Compact duplicate entries out of a minimal symbol table by walking
|
||
through the table and compacting out entries with duplicate addresses
|
||
and matching names. Return the number of entries remaining.
|
||
|
||
On entry, the table resides between msymbol[0] and msymbol[mcount].
|
||
On exit, it resides between msymbol[0] and msymbol[result_count].
|
||
|
||
When files contain multiple sources of symbol information, it is
|
||
possible for the minimal symbol table to contain many duplicate entries.
|
||
As an example, SVR4 systems use ELF formatted object files, which
|
||
usually contain at least two different types of symbol tables (a
|
||
standard ELF one and a smaller dynamic linking table), as well as
|
||
DWARF debugging information for files compiled with -g.
|
||
|
||
Without compacting, the minimal symbol table for gdb itself contains
|
||
over a 1000 duplicates, about a third of the total table size. Aside
|
||
from the potential trap of not noticing that two successive entries
|
||
identify the same location, this duplication impacts the time required
|
||
to linearly scan the table, which is done in a number of places. So we
|
||
just do one linear scan here and toss out the duplicates.
|
||
|
||
Since the different sources of information for each symbol may
|
||
have different levels of "completeness", we may have duplicates
|
||
that have one entry with type "mst_unknown" and the other with a
|
||
known type. So if the one we are leaving alone has type mst_unknown,
|
||
overwrite its type with the type from the one we are compacting out. */
|
||
|
||
static int
|
||
compact_minimal_symbols (struct minimal_symbol *msymbol, int mcount,
|
||
struct objfile *objfile)
|
||
{
|
||
struct minimal_symbol *copyfrom;
|
||
struct minimal_symbol *copyto;
|
||
|
||
if (mcount > 0)
|
||
{
|
||
copyfrom = copyto = msymbol;
|
||
while (copyfrom < msymbol + mcount - 1)
|
||
{
|
||
if (MSYMBOL_VALUE_RAW_ADDRESS (copyfrom)
|
||
== MSYMBOL_VALUE_RAW_ADDRESS ((copyfrom + 1))
|
||
&& MSYMBOL_SECTION (copyfrom) == MSYMBOL_SECTION (copyfrom + 1)
|
||
&& strcmp (MSYMBOL_LINKAGE_NAME (copyfrom),
|
||
MSYMBOL_LINKAGE_NAME ((copyfrom + 1))) == 0)
|
||
{
|
||
if (MSYMBOL_TYPE ((copyfrom + 1)) == mst_unknown)
|
||
{
|
||
MSYMBOL_TYPE ((copyfrom + 1)) = MSYMBOL_TYPE (copyfrom);
|
||
}
|
||
copyfrom++;
|
||
}
|
||
else
|
||
*copyto++ = *copyfrom++;
|
||
}
|
||
*copyto++ = *copyfrom++;
|
||
mcount = copyto - msymbol;
|
||
}
|
||
return (mcount);
|
||
}
|
||
|
||
/* Build (or rebuild) the minimal symbol hash tables. This is necessary
|
||
after compacting or sorting the table since the entries move around
|
||
thus causing the internal minimal_symbol pointers to become jumbled. */
|
||
|
||
static void
|
||
build_minimal_symbol_hash_tables (struct objfile *objfile)
|
||
{
|
||
int i;
|
||
struct minimal_symbol *msym;
|
||
|
||
/* Clear the hash tables. */
|
||
for (i = 0; i < MINIMAL_SYMBOL_HASH_SIZE; i++)
|
||
{
|
||
objfile->per_bfd->msymbol_hash[i] = 0;
|
||
objfile->per_bfd->msymbol_demangled_hash[i] = 0;
|
||
}
|
||
|
||
/* Now, (re)insert the actual entries. */
|
||
for ((i = objfile->per_bfd->minimal_symbol_count,
|
||
msym = objfile->per_bfd->msymbols.get ());
|
||
i > 0;
|
||
i--, msym++)
|
||
{
|
||
msym->hash_next = 0;
|
||
add_minsym_to_hash_table (msym, objfile->per_bfd->msymbol_hash);
|
||
|
||
msym->demangled_hash_next = 0;
|
||
if (MSYMBOL_SEARCH_NAME (msym) != MSYMBOL_LINKAGE_NAME (msym))
|
||
add_minsym_to_demangled_hash_table (msym, objfile);
|
||
}
|
||
}
|
||
|
||
/* Add the minimal symbols in the existing bunches to the objfile's official
|
||
minimal symbol table. In most cases there is no minimal symbol table yet
|
||
for this objfile, and the existing bunches are used to create one. Once
|
||
in a while (for shared libraries for example), we add symbols (e.g. common
|
||
symbols) to an existing objfile. */
|
||
|
||
void
|
||
minimal_symbol_reader::install ()
|
||
{
|
||
int mcount;
|
||
struct msym_bunch *bunch;
|
||
struct minimal_symbol *msymbols;
|
||
int alloc_count;
|
||
|
||
if (m_objfile->per_bfd->minsyms_read)
|
||
return;
|
||
|
||
if (m_msym_count > 0)
|
||
{
|
||
if (symtab_create_debug)
|
||
{
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"Installing %d minimal symbols of objfile %s.\n",
|
||
m_msym_count, objfile_name (m_objfile));
|
||
}
|
||
|
||
/* Allocate enough space, into which we will gather the bunches
|
||
of new and existing minimal symbols, sort them, and then
|
||
compact out the duplicate entries. Once we have a final
|
||
table, we will give back the excess space. */
|
||
|
||
alloc_count = m_msym_count + m_objfile->per_bfd->minimal_symbol_count;
|
||
gdb::unique_xmalloc_ptr<minimal_symbol>
|
||
msym_holder (XNEWVEC (minimal_symbol, alloc_count));
|
||
msymbols = msym_holder.get ();
|
||
|
||
/* Copy in the existing minimal symbols, if there are any. */
|
||
|
||
if (m_objfile->per_bfd->minimal_symbol_count)
|
||
memcpy (msymbols, m_objfile->per_bfd->msymbols.get (),
|
||
m_objfile->per_bfd->minimal_symbol_count
|
||
* sizeof (struct minimal_symbol));
|
||
|
||
/* Walk through the list of minimal symbol bunches, adding each symbol
|
||
to the new contiguous array of symbols. Note that we start with the
|
||
current, possibly partially filled bunch (thus we use the current
|
||
msym_bunch_index for the first bunch we copy over), and thereafter
|
||
each bunch is full. */
|
||
|
||
mcount = m_objfile->per_bfd->minimal_symbol_count;
|
||
|
||
for (bunch = m_msym_bunch; bunch != NULL; bunch = bunch->next)
|
||
{
|
||
memcpy (&msymbols[mcount], &bunch->contents[0],
|
||
m_msym_bunch_index * sizeof (struct minimal_symbol));
|
||
mcount += m_msym_bunch_index;
|
||
m_msym_bunch_index = BUNCH_SIZE;
|
||
}
|
||
|
||
/* Sort the minimal symbols by address. */
|
||
|
||
qsort (msymbols, mcount, sizeof (struct minimal_symbol),
|
||
compare_minimal_symbols);
|
||
|
||
/* Compact out any duplicates, and free up whatever space we are
|
||
no longer using. */
|
||
|
||
mcount = compact_minimal_symbols (msymbols, mcount, m_objfile);
|
||
msym_holder.reset (XRESIZEVEC (struct minimal_symbol,
|
||
msym_holder.release (),
|
||
mcount));
|
||
|
||
/* Attach the minimal symbol table to the specified objfile.
|
||
The strings themselves are also located in the storage_obstack
|
||
of this objfile. */
|
||
|
||
m_objfile->per_bfd->minimal_symbol_count = mcount;
|
||
m_objfile->per_bfd->msymbols = std::move (msym_holder);
|
||
|
||
build_minimal_symbol_hash_tables (m_objfile);
|
||
}
|
||
}
|
||
|
||
/* Check if PC is in a shared library trampoline code stub.
|
||
Return minimal symbol for the trampoline entry or NULL if PC is not
|
||
in a trampoline code stub. */
|
||
|
||
static struct minimal_symbol *
|
||
lookup_solib_trampoline_symbol_by_pc (CORE_ADDR pc)
|
||
{
|
||
bound_minimal_symbol msymbol
|
||
= lookup_minimal_symbol_by_pc_section (pc, NULL,
|
||
lookup_msym_prefer::TRAMPOLINE);
|
||
|
||
if (msymbol.minsym != NULL
|
||
&& MSYMBOL_TYPE (msymbol.minsym) == mst_solib_trampoline)
|
||
return msymbol.minsym;
|
||
return NULL;
|
||
}
|
||
|
||
/* If PC is in a shared library trampoline code stub, return the
|
||
address of the `real' function belonging to the stub.
|
||
Return 0 if PC is not in a trampoline code stub or if the real
|
||
function is not found in the minimal symbol table.
|
||
|
||
We may fail to find the right function if a function with the
|
||
same name is defined in more than one shared library, but this
|
||
is considered bad programming style. We could return 0 if we find
|
||
a duplicate function in case this matters someday. */
|
||
|
||
CORE_ADDR
|
||
find_solib_trampoline_target (struct frame_info *frame, CORE_ADDR pc)
|
||
{
|
||
struct minimal_symbol *tsymbol = lookup_solib_trampoline_symbol_by_pc (pc);
|
||
|
||
if (tsymbol != NULL)
|
||
{
|
||
for (objfile *objfile : current_program_space->objfiles ())
|
||
{
|
||
for (minimal_symbol *msymbol : objfile->msymbols ())
|
||
{
|
||
/* Also handle minimal symbols pointing to function
|
||
descriptors. */
|
||
if ((MSYMBOL_TYPE (msymbol) == mst_text
|
||
|| MSYMBOL_TYPE (msymbol) == mst_text_gnu_ifunc
|
||
|| MSYMBOL_TYPE (msymbol) == mst_data
|
||
|| MSYMBOL_TYPE (msymbol) == mst_data_gnu_ifunc)
|
||
&& strcmp (MSYMBOL_LINKAGE_NAME (msymbol),
|
||
MSYMBOL_LINKAGE_NAME (tsymbol)) == 0)
|
||
{
|
||
CORE_ADDR func;
|
||
|
||
/* Ignore data symbols that are not function
|
||
descriptors. */
|
||
if (msymbol_is_function (objfile, msymbol, &func))
|
||
return func;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
return 0;
|
||
}
|
||
|
||
/* See minsyms.h. */
|
||
|
||
CORE_ADDR
|
||
minimal_symbol_upper_bound (struct bound_minimal_symbol minsym)
|
||
{
|
||
int i;
|
||
short section;
|
||
struct obj_section *obj_section;
|
||
CORE_ADDR result;
|
||
struct minimal_symbol *msymbol;
|
||
|
||
gdb_assert (minsym.minsym != NULL);
|
||
|
||
/* If the minimal symbol has a size, use it. Otherwise use the
|
||
lesser of the next minimal symbol in the same section, or the end
|
||
of the section, as the end of the function. */
|
||
|
||
if (MSYMBOL_SIZE (minsym.minsym) != 0)
|
||
return BMSYMBOL_VALUE_ADDRESS (minsym) + MSYMBOL_SIZE (minsym.minsym);
|
||
|
||
/* Step over other symbols at this same address, and symbols in
|
||
other sections, to find the next symbol in this section with a
|
||
different address. */
|
||
|
||
msymbol = minsym.minsym;
|
||
section = MSYMBOL_SECTION (msymbol);
|
||
for (i = 1; MSYMBOL_LINKAGE_NAME (msymbol + i) != NULL; i++)
|
||
{
|
||
if ((MSYMBOL_VALUE_RAW_ADDRESS (msymbol + i)
|
||
!= MSYMBOL_VALUE_RAW_ADDRESS (msymbol))
|
||
&& MSYMBOL_SECTION (msymbol + i) == section)
|
||
break;
|
||
}
|
||
|
||
obj_section = MSYMBOL_OBJ_SECTION (minsym.objfile, minsym.minsym);
|
||
if (MSYMBOL_LINKAGE_NAME (msymbol + i) != NULL
|
||
&& (MSYMBOL_VALUE_ADDRESS (minsym.objfile, msymbol + i)
|
||
< obj_section_endaddr (obj_section)))
|
||
result = MSYMBOL_VALUE_ADDRESS (minsym.objfile, msymbol + i);
|
||
else
|
||
/* We got the start address from the last msymbol in the objfile.
|
||
So the end address is the end of the section. */
|
||
result = obj_section_endaddr (obj_section);
|
||
|
||
return result;
|
||
}
|