| /* GDB routines for manipulating the minimal symbol tables. |
| Copyright (C) 1992-2017 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 "symbol.h" |
| |
| /* Accumulate the minimal symbols for each objfile in bunches of BUNCH_SIZE. |
| At the end, copy them all into one newly allocated location on an objfile's |
| per-BFD storage obstack. */ |
| |
| #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_const (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 minimal_symbol **table) |
| { |
| if (sym->demangled_hash_next == NULL) |
| { |
| unsigned int hash = msymbol_hash_iw (MSYMBOL_SEARCH_NAME (sym)) |
| % MINIMAL_SYMBOL_HASH_SIZE; |
| |
| sym->demangled_hash_next = table[hash]; |
| table[hash] = sym; |
| } |
| } |
| |
| /* 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; |
| struct bound_minimal_symbol found_symbol = { NULL, NULL }; |
| struct bound_minimal_symbol found_file_symbol = { NULL, NULL }; |
| struct bound_minimal_symbol trampoline_symbol = { NULL, NULL }; |
| |
| unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE; |
| unsigned int dem_hash = msymbol_hash_iw (name) % MINIMAL_SYMBOL_HASH_SIZE; |
| |
| const char *modified_name = name; |
| |
| if (sfile != NULL) |
| sfile = lbasename (sfile); |
| |
| /* For C++, canonicalize the input name. */ |
| std::string modified_name_storage; |
| if (current_language->la_language == language_cplus) |
| { |
| std::string cname = cp_canonicalize_string (name); |
| if (!cname.empty ()) |
| { |
| std::swap (modified_name_storage, cname); |
| modified_name = modified_name_storage.c_str (); |
| } |
| } |
| |
| for (objfile = object_files; |
| objfile != NULL && found_symbol.minsym == NULL; |
| objfile = objfile->next) |
| { |
| struct minimal_symbol *msymbol; |
| |
| if (objf == NULL || objf == objfile |
| || objf == objfile->separate_debug_objfile_backlink) |
| { |
| /* Do two passes: the first over the ordinary hash table, |
| and the second over the demangled hash table. */ |
| int pass; |
| |
| if (symbol_lookup_debug) |
| { |
| fprintf_unfiltered (gdb_stdlog, |
| "lookup_minimal_symbol (%s, %s, %s)\n", |
| name, sfile != NULL ? sfile : "NULL", |
| objfile_debug_name (objfile)); |
| } |
| |
| for (pass = 1; pass <= 2 && found_symbol.minsym == NULL; pass++) |
| { |
| /* Select hash list according to pass. */ |
| if (pass == 1) |
| msymbol = objfile->per_bfd->msymbol_hash[hash]; |
| else |
| msymbol = objfile->per_bfd->msymbol_demangled_hash[dem_hash]; |
| |
| while (msymbol != NULL && found_symbol.minsym == NULL) |
| { |
| int match; |
| |
| if (pass == 1) |
| { |
| int (*cmp) (const char *, const char *); |
| |
| cmp = (case_sensitivity == case_sensitive_on |
| ? strcmp : strcasecmp); |
| match = cmp (MSYMBOL_LINKAGE_NAME (msymbol), |
| modified_name) == 0; |
| } |
| else |
| { |
| /* The function respects CASE_SENSITIVITY. */ |
| match = MSYMBOL_MATCHES_SEARCH_NAME (msymbol, |
| modified_name); |
| } |
| |
| if (match) |
| { |
| 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) |
| { |
| found_file_symbol.minsym = msymbol; |
| found_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: |
| found_symbol.minsym = msymbol; |
| found_symbol.objfile = objfile; |
| break; |
| } |
| } |
| |
| /* Find the next symbol on the hash chain. */ |
| if (pass == 1) |
| msymbol = msymbol->hash_next; |
| else |
| msymbol = msymbol->demangled_hash_next; |
| } |
| } |
| } |
| } |
| |
| /* External symbols are best. */ |
| if (found_symbol.minsym != NULL) |
| { |
| if (symbol_lookup_debug) |
| { |
| fprintf_unfiltered (gdb_stdlog, |
| "lookup_minimal_symbol (...) = %s" |
| " (external)\n", |
| host_address_to_string (found_symbol.minsym)); |
| } |
| return found_symbol; |
| } |
| |
| /* File-local symbols are next best. */ |
| if (found_file_symbol.minsym != NULL) |
| { |
| if (symbol_lookup_debug) |
| { |
| fprintf_unfiltered (gdb_stdlog, |
| "lookup_minimal_symbol (...) = %s" |
| " (file-local)\n", |
| host_address_to_string |
| (found_file_symbol.minsym)); |
| } |
| return found_file_symbol; |
| } |
| |
| /* Symbols for shared library trampolines are next best. */ |
| if (symbol_lookup_debug) |
| { |
| fprintf_unfiltered (gdb_stdlog, |
| "lookup_minimal_symbol (...) = %s%s\n", |
| trampoline_symbol.minsym != NULL |
| ? host_address_to_string (trampoline_symbol.minsym) |
| : "NULL", |
| trampoline_symbol.minsym != NULL |
| ? " (trampoline)" : ""); |
| } |
| return trampoline_symbol; |
| } |
| |
| /* 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; |
| } |
| |
| /* See minsyms.h. */ |
| |
| void |
| iterate_over_minimal_symbols (struct objfile *objf, const char *name, |
| void (*callback) (struct minimal_symbol *, |
| void *), |
| void *user_data) |
| { |
| unsigned int hash; |
| struct minimal_symbol *iter; |
| int (*cmp) (const char *, const char *); |
| |
| /* The first pass is over the ordinary hash table. */ |
| hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE; |
| iter = objf->per_bfd->msymbol_hash[hash]; |
| cmp = (case_sensitivity == case_sensitive_on ? strcmp : strcasecmp); |
| while (iter) |
| { |
| if (cmp (MSYMBOL_LINKAGE_NAME (iter), name) == 0) |
| (*callback) (iter, user_data); |
| iter = iter->hash_next; |
| } |
| |
| /* The second pass is over the demangled table. */ |
| hash = msymbol_hash_iw (name) % MINIMAL_SYMBOL_HASH_SIZE; |
| iter = objf->per_bfd->msymbol_demangled_hash[hash]; |
| while (iter) |
| { |
| if (MSYMBOL_MATCHES_SEARCH_NAME (iter, name)) |
| (*callback) (iter, user_data); |
| iter = iter->demangled_hash_next; |
| } |
| } |
| |
| /* 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; |
| } |
| |
| /* 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. */ |
| |
| static struct bound_minimal_symbol |
| lookup_minimal_symbol_by_pc_section_1 (CORE_ADDR pc_in, |
| struct obj_section *section, |
| int want_trampoline) |
| { |
| 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; |
| enum minimal_symbol_type want_type, other_type; |
| |
| want_type = want_trampoline ? mst_solib_trampoline : mst_text; |
| other_type = want_trampoline ? mst_text : mst_solib_trampoline; |
| |
| /* 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. Note that a minimal symbol table always consists |
| of at least two symbols, a "real" symbol and the terminating |
| "null symbol". If there are no real symbols, then there is no |
| minimal symbol table at all. */ |
| |
| if (objfile->per_bfd->minimal_symbol_count > 0) |
| { |
| int best_zero_sized = -1; |
| |
| msymbol = objfile->per_bfd->msymbols; |
| 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]) == other_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; |
| } |
| |
| struct bound_minimal_symbol |
| lookup_minimal_symbol_by_pc_section (CORE_ADDR pc, struct obj_section *section) |
| { |
| if (section == NULL) |
| { |
| /* NOTE: cagney/2004-01-27: This was using find_pc_mapped_section to |
| force the section but that (well unless you're doing overlay |
| debugging) always returns NULL making the call somewhat useless. */ |
| section = find_pc_section (pc); |
| if (section == NULL) |
| { |
| struct bound_minimal_symbol result; |
| |
| memset (&result, 0, sizeof (result)); |
| return result; |
| } |
| } |
| return lookup_minimal_symbol_by_pc_section_1 (pc, section, 0); |
| } |
| |
| /* See minsyms.h. */ |
| |
| struct bound_minimal_symbol |
| lookup_minimal_symbol_by_pc (CORE_ADDR pc) |
| { |
| struct obj_section *section = find_pc_section (pc); |
| |
| if (section == NULL) |
| { |
| struct bound_minimal_symbol result; |
| |
| memset (&result, 0, sizeof (result)); |
| return result; |
| } |
| return lookup_minimal_symbol_by_pc_section_1 (pc, section, 0); |
| } |
| |
| /* Return non-zero iff PC is in an STT_GNU_IFUNC function resolver. */ |
| |
| int |
| in_gnu_ifunc_stub (CORE_ADDR pc) |
| { |
| struct bound_minimal_symbol msymbol = lookup_minimal_symbol_by_pc (pc); |
| |
| 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; |
| |
| /* See minsyms.h. */ |
| |
| struct bound_minimal_symbol |
| lookup_minimal_symbol_and_objfile (const char *name) |
| { |
| struct bound_minimal_symbol result; |
| struct objfile *objfile; |
| unsigned int hash = msymbol_hash (name) % MINIMAL_SYMBOL_HASH_SIZE; |
| |
| ALL_OBJFILES (objfile) |
| { |
| struct minimal_symbol *msym; |
| |
| for (msym = objfile->per_bfd->msymbol_hash[hash]; |
| msym != NULL; |
| msym = msym->hash_next) |
| { |
| if (strcmp (MSYMBOL_LINKAGE_NAME (msym), name) == 0) |
| { |
| result.minsym = msym; |
| result.objfile = objfile; |
| return result; |
| } |
| } |
| } |
| |
| memset (&result, 0, sizeof (result)); |
| return result; |
| } |
| |
| |
| /* 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. |
| |
| FIXME: We could allocate the minimal symbol bunches on their own |
| obstack and then simply blow the obstack away when we are done with |
| it. Is it worth the extra trouble though? */ |
| |
| 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_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); |
| } |
| |
| /* 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 (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]; |
| MSYMBOL_SET_LANGUAGE (msymbol, language_auto, |
| &m_objfile->per_bfd->storage_obstack); |
| MSYMBOL_SET_NAMES (msymbol, name, name_len, copy_name, m_objfile); |
| |
| SET_MSYMBOL_VALUE_ADDRESS (msymbol, address); |
| MSYMBOL_SECTION (msymbol) = section; |
| |
| MSYMBOL_TYPE (msymbol) = ms_type; |
| MSYMBOL_TARGET_FLAG_1 (msymbol) = 0; |
| MSYMBOL_TARGET_FLAG_2 (msymbol) = 0; |
| /* Do not use the SET_MSYMBOL_SIZE macro to initialize the size, |
| as it would also set the has_size flag. */ |
| msymbol->size = 0; |
| |
| /* The hash pointers must be cleared! If they're not, |
| add_minsym_to_hash_table will NOT add this msymbol to the hash table. */ |
| msymbol->hash_next = NULL; |
| msymbol->demangled_hash_next = NULL; |
| |
| /* 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. |
| |
| Note that we are not concerned here about recovering the space that |
| is potentially freed up, because the strings themselves are allocated |
| on the storage_obstack, and will get automatically freed when the symbol |
| table is freed. The caller can free up the unused minimal symbols at |
| the end of the compacted region if their allocation strategy allows it. |
| |
| Also note we only go up to the next to last entry within the loop |
| and then copy the last entry explicitly after the loop terminates. |
| |
| 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); |
| 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->per_bfd->msymbol_demangled_hash); |
| } |
| } |
| |
| /* 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. |
| |
| Because of the way minimal symbols are collected, we generally have no way |
| of knowing what source language applies to any particular minimal symbol. |
| Specifically, we have no way of knowing if the minimal symbol comes from a |
| C++ compilation unit or not. So for the sake of supporting cached |
| demangled C++ names, we have no choice but to try and demangle each new one |
| that comes in. If the demangling succeeds, then we assume it is a C++ |
| symbol and set the symbol's language and demangled name fields |
| appropriately. Note that in order to avoid unnecessary demanglings, and |
| allocating obstack space that subsequently can't be freed for the demangled |
| names, we mark all newly added symbols with language_auto. After |
| compaction of the minimal symbols, we go back and scan the entire minimal |
| symbol table looking for these new symbols. For each new symbol we attempt |
| to demangle it, and if successful, record it as a language_cplus symbol |
| and cache the demangled form on the symbol obstack. Symbols which don't |
| demangle are marked as language_unknown symbols, which inhibits future |
| attempts to demangle them if we later add more minimal symbols. */ |
| |
| void |
| minimal_symbol_reader::install () |
| { |
| int bindex; |
| 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 in the obstack, 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 + 1; |
| obstack_blank (&m_objfile->per_bfd->storage_obstack, |
| alloc_count * sizeof (struct minimal_symbol)); |
| msymbols = (struct minimal_symbol *) |
| obstack_base (&m_objfile->per_bfd->storage_obstack); |
| |
| /* Copy in the existing minimal symbols, if there are any. */ |
| |
| if (m_objfile->per_bfd->minimal_symbol_count) |
| memcpy ((char *) msymbols, (char *) m_objfile->per_bfd->msymbols, |
| 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) |
| { |
| for (bindex = 0; bindex < m_msym_bunch_index; bindex++, mcount++) |
| msymbols[mcount] = bunch->contents[bindex]; |
| 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); |
| |
| obstack_blank_fast (&m_objfile->per_bfd->storage_obstack, |
| (mcount + 1 - alloc_count) * sizeof (struct minimal_symbol)); |
| msymbols = (struct minimal_symbol *) |
| obstack_finish (&m_objfile->per_bfd->storage_obstack); |
| |
| /* We also terminate the minimal symbol table with a "null symbol", |
| which is *not* included in the size of the table. This makes it |
| easier to find the end of the table when we are handed a pointer |
| to some symbol in the middle of it. Zero out the fields in the |
| "null symbol" allocated at the end of the array. Note that the |
| symbol count does *not* include this null symbol, which is why it |
| is indexed by mcount and not mcount-1. */ |
| |
| memset (&msymbols[mcount], 0, sizeof (struct minimal_symbol)); |
| |
| /* 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 = msymbols; |
| |
| /* Now build the hash tables; we can't do this incrementally |
| at an earlier point since we weren't finished with the obstack |
| yet. (And if the msymbol obstack gets moved, all the internal |
| pointers to other msymbols need to be adjusted.) */ |
| build_minimal_symbol_hash_tables (m_objfile); |
| } |
| } |
| |
| /* See minsyms.h. */ |
| |
| void |
| terminate_minimal_symbol_table (struct objfile *objfile) |
| { |
| if (! objfile->per_bfd->msymbols) |
| objfile->per_bfd->msymbols |
| = ((struct minimal_symbol *) |
| obstack_alloc (&objfile->per_bfd->storage_obstack, |
| sizeof (struct minimal_symbol))); |
| |
| { |
| struct minimal_symbol *m |
| = &objfile->per_bfd->msymbols[objfile->per_bfd->minimal_symbol_count]; |
| |
| memset (m, 0, sizeof (*m)); |
| /* Don't rely on these enumeration values being 0's. */ |
| MSYMBOL_TYPE (m) = mst_unknown; |
| MSYMBOL_SET_LANGUAGE (m, language_unknown, |
| &objfile->per_bfd->storage_obstack); |
| } |
| } |
| |
| /* 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) |
| { |
| struct obj_section *section = find_pc_section (pc); |
| struct bound_minimal_symbol msymbol; |
| |
| if (section == NULL) |
| return NULL; |
| msymbol = lookup_minimal_symbol_by_pc_section_1 (pc, section, 1); |
| |
| 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 objfile *objfile; |
| struct minimal_symbol *msymbol; |
| struct minimal_symbol *tsymbol = lookup_solib_trampoline_symbol_by_pc (pc); |
| |
| if (tsymbol != NULL) |
| { |
| ALL_MSYMBOLS (objfile, msymbol) |
| { |
| if ((MSYMBOL_TYPE (msymbol) == mst_text |
| || MSYMBOL_TYPE (msymbol) == mst_text_gnu_ifunc) |
| && strcmp (MSYMBOL_LINKAGE_NAME (msymbol), |
| MSYMBOL_LINKAGE_NAME (tsymbol)) == 0) |
| return MSYMBOL_VALUE_ADDRESS (objfile, msymbol); |
| |
| /* Also handle minimal symbols pointing to function descriptors. */ |
| if (MSYMBOL_TYPE (msymbol) == mst_data |
| && strcmp (MSYMBOL_LINKAGE_NAME (msymbol), |
| MSYMBOL_LINKAGE_NAME (tsymbol)) == 0) |
| { |
| CORE_ADDR func; |
| |
| func = gdbarch_convert_from_func_ptr_addr |
| (get_objfile_arch (objfile), |
| MSYMBOL_VALUE_ADDRESS (objfile, msymbol), |
| ¤t_target); |
| |
| /* Ignore data symbols that are not function descriptors. */ |
| if (func != MSYMBOL_VALUE_ADDRESS (objfile, msymbol)) |
| 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; |
| } |