diff options
Diffstat (limited to 'libdwfl/dwfl_module_addrsym.c')
| -rw-r--r-- | libdwfl/dwfl_module_addrsym.c | 115 |
1 files changed, 65 insertions, 50 deletions
diff --git a/libdwfl/dwfl_module_addrsym.c b/libdwfl/dwfl_module_addrsym.c index 41ff4654..9ced0cfb 100644 --- a/libdwfl/dwfl_module_addrsym.c +++ b/libdwfl/dwfl_module_addrsym.c @@ -1,5 +1,5 @@ /* Find debugging and symbol information for a module in libdwfl. - Copyright (C) 2005-2010 Red Hat, Inc. + Copyright (C) 2005-2011 Red Hat, Inc. This file is part of Red Hat elfutils. Red Hat elfutils is free software; you can redistribute it and/or modify @@ -105,69 +105,84 @@ dwfl_module_addrsym (Dwfl_Module *mod, GElf_Addr addr, GElf_Addr min_label = 0; /* Look through the symbol table for a matching symbol. */ - for (int i = 1; i < syments; ++i) + inline void search_table (int start, int end) { - GElf_Sym sym; - GElf_Word shndx; - const char *name = INTUSE(dwfl_module_getsym) (mod, i, &sym, &shndx); - if (name != NULL && name[0] != '\0' - && sym.st_shndx != SHN_UNDEF - && sym.st_value <= addr - && GELF_ST_TYPE (sym.st_info) != STT_SECTION - && GELF_ST_TYPE (sym.st_info) != STT_FILE - && GELF_ST_TYPE (sym.st_info) != STT_TLS) + for (int i = start; i < end; ++i) { - /* Even if we don't choose this symbol, its existence excludes - any sizeless symbol (assembly label) that is below its upper - bound. */ - if (sym.st_value + sym.st_size > min_label) - min_label = sym.st_value + sym.st_size; - - if (sym.st_size == 0 || addr - sym.st_value < sym.st_size) + GElf_Sym sym; + GElf_Word shndx; + const char *name = INTUSE(dwfl_module_getsym) (mod, i, &sym, &shndx); + if (name != NULL && name[0] != '\0' + && sym.st_shndx != SHN_UNDEF + && sym.st_value <= addr + && GELF_ST_TYPE (sym.st_info) != STT_SECTION + && GELF_ST_TYPE (sym.st_info) != STT_FILE + && GELF_ST_TYPE (sym.st_info) != STT_TLS) { - /* This symbol is a better candidate than the current one - if it's closer to ADDR or is global when it was local. */ - if (closest_name == NULL - || closest_sym->st_value < sym.st_value - || (GELF_ST_BIND (closest_sym->st_info) - < GELF_ST_BIND (sym.st_info))) + /* Even if we don't choose this symbol, its existence excludes + any sizeless symbol (assembly label) that is below its upper + bound. */ + if (sym.st_value + sym.st_size > min_label) + min_label = sym.st_value + sym.st_size; + + if (sym.st_size == 0 || addr - sym.st_value < sym.st_size) { - if (sym.st_size != 0) + /* This symbol is a better candidate than the current one + if it's closer to ADDR or is global when it was local. */ + if (closest_name == NULL + || closest_sym->st_value < sym.st_value + || (GELF_ST_BIND (closest_sym->st_info) + < GELF_ST_BIND (sym.st_info))) + { + if (sym.st_size != 0) + { + *closest_sym = sym; + closest_shndx = shndx; + closest_name = name; + } + else if (closest_name == NULL + && sym.st_value >= min_label + && same_section (&sym, shndx)) + { + /* Handwritten assembly symbols sometimes have no + st_size. If no symbol with proper size includes + the address, we'll use the closest one that is in + the same section as ADDR. */ + sizeless_sym = sym; + sizeless_shndx = shndx; + sizeless_name = name; + } + } + /* When the beginning of its range is no closer, + the end of its range might be. But do not + replace a global symbol with a local! */ + else if (sym.st_size != 0 + && closest_sym->st_value == sym.st_value + && closest_sym->st_size > sym.st_size + && (GELF_ST_BIND (closest_sym->st_info) + <= GELF_ST_BIND (sym.st_info))) { *closest_sym = sym; closest_shndx = shndx; closest_name = name; } - else if (closest_name == NULL - && sym.st_value >= min_label - && same_section (&sym, shndx)) - { - /* Handwritten assembly symbols sometimes have no - st_size. If no symbol with proper size includes - the address, we'll use the closest one that is in - the same section as ADDR. */ - sizeless_sym = sym; - sizeless_shndx = shndx; - sizeless_name = name; - } - } - /* When the beginning of its range is no closer, - the end of its range might be. But do not - replace a global symbol with a local! */ - else if (sym.st_size != 0 - && closest_sym->st_value == sym.st_value - && closest_sym->st_size > sym.st_size - && (GELF_ST_BIND (closest_sym->st_info) - <= GELF_ST_BIND (sym.st_info))) - { - *closest_sym = sym; - closest_shndx = shndx; - closest_name = name; } } } } + /* First go through global symbols. mod->first_global is setup by + dwfl_module_getsymtab to the index of the first global symbol in + the module's symbol table, or -1 when unknown. All symbols with + local binding come first in the symbol table, then all globals. */ + search_table (mod->first_global < 0 ? 1 : mod->first_global, syments); + + /* If we found nothing searching the global symbols, then try the locals. + Unless we have a global sizeless symbol that matches exactly. */ + if (closest_name == NULL && mod->first_global > 1 + && (sizeless_name == NULL || sizeless_sym.st_value != addr)) + search_table (1, mod->first_global); + /* If we found no proper sized symbol to use, fall back to the best candidate sizeless symbol we found, if any. */ if (closest_name == NULL |