diff options
Diffstat (limited to 'backends/ppc64_get_func_pc.c')
| -rw-r--r-- | backends/ppc64_get_func_pc.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/backends/ppc64_get_func_pc.c b/backends/ppc64_get_func_pc.c new file mode 100644 index 00000000..5038b00b --- /dev/null +++ b/backends/ppc64_get_func_pc.c @@ -0,0 +1,195 @@ +/* Convert function descriptor SYM to the function PC value in-place. + Copyright (C) 2012 Red Hat, Inc. + This file is part of elfutils. + + This file is free software; you can redistribute it and/or modify + it under the terms of either + + * the GNU Lesser General Public License as published by the Free + Software Foundation; either version 3 of the License, or (at + your option) any later version + + or + + * the GNU General Public License as published by the Free + Software Foundation; either version 2 of the License, or (at + your option) any later version + + or both in parallel, as here. + + elfutils 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 copies of the GNU General Public License and + the GNU Lesser General Public License along with this program. If + not, see <http://www.gnu.org/licenses/>. */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +#include <assert.h> +#include "libdwfl.h" +#include <endian.h> +#include <string.h> +#include <stdlib.h> + +#define BACKEND ppc64_ +#include "libebl_CPU.h" + +struct pc_entry +{ + /* sym_from must be the very first element for the use in bsearch below. */ + GElf_Sym sym_from; + Elf64_Addr st_value_to; + const char *name_to; +}; + +struct pc_table +{ + size_t nelem; + struct pc_entry a[]; + /* Here follow strings allocated for pc_entry->name_to. */ +}; + +static int +compar (const void *a_voidp, const void *b_voidp) +{ + const struct pc_entry *a = a_voidp; + const struct pc_entry *b = b_voidp; + + return memcmp (&a->sym_from, &b->sym_from, sizeof (a->sym_from)); +} + +static void +init (Ebl *ebl, Dwfl_Module *mod) +{ + int syments = dwfl_module_getsymtab (mod); + assert (syments >= 0); + size_t funcs = 0; + size_t names_size = 0; + Elf *elf = ebl->elf; + if (elf == NULL) + return; + GElf_Ehdr ehdr_mem, *ehdr = gelf_getehdr (elf, &ehdr_mem); + if (ehdr == NULL) + return; + GElf_Word shndx, opd_shndx = 0; + /* Needless initialization for old GCCs. */ + Elf_Data *opd_data = NULL; + /* Needless initialization for old GCCs. */ + GElf_Shdr opd_shdr_mem, *opd_shdr = NULL; + Dwarf_Addr symbias; + dwfl_module_info (mod, NULL, NULL, NULL, NULL, &symbias, NULL, NULL); + for (int symi = 1; symi < syments; symi++) + { + GElf_Sym sym; + const char *symname = dwfl_module_getsym (mod, symi, &sym, &shndx); + if (symname == NULL || GELF_ST_TYPE (sym.st_info) != STT_FUNC) + continue; + if (sym.st_shndx != SHN_XINDEX) + shndx = sym.st_shndx; + /* Zero is invalid value but it could crash this code. */ + if (shndx == 0) + continue; + if (opd_shndx == 0) + { + Elf_Scn *scn = elf_getscn (elf, shndx); + if (scn == NULL) + continue; + opd_shdr = gelf_getshdr (scn, &opd_shdr_mem); + if (opd_shdr == NULL) + continue; + if (strcmp (elf_strptr (elf, ehdr->e_shstrndx, opd_shdr->sh_name), + ".opd") != 0) + continue; + opd_data = elf_getdata (scn, NULL); + /* SHT_NOBITS will produce NULL D_BUF. */ + if (opd_data == NULL || opd_data->d_buf == NULL) + return; + assert (opd_data->d_size == opd_shdr->sh_size); + opd_shndx = shndx; + } + if (shndx != opd_shndx) + continue; + Elf64_Addr val; + if (sym.st_value < opd_shdr->sh_addr + symbias + || sym.st_value > (opd_shdr->sh_addr + symbias + + opd_shdr->sh_size - sizeof (val))) + continue; + funcs++; + names_size += 1 + strlen (symname) + 1; + } + struct pc_table *pc_table; + pc_table = malloc (sizeof (*pc_table) + funcs * sizeof (*pc_table->a) + + names_size); + if (pc_table == NULL) + return; + ebl->backend = pc_table; + pc_table->nelem = 0; + if (funcs == 0) + return; + struct pc_entry *dest = pc_table->a; + char *names = (void *) (pc_table->a + funcs), *names_dest = names; + for (int symi = 1; symi < syments; symi++) + { + GElf_Sym sym; + const char *symname = dwfl_module_getsym (mod, symi, &sym, &shndx); + if (symname == NULL || GELF_ST_TYPE (sym.st_info) != STT_FUNC) + continue; + if (sym.st_shndx != SHN_XINDEX) + shndx = sym.st_shndx; + if (shndx != opd_shndx) + continue; + uint64_t val64; + if (sym.st_value < opd_shdr->sh_addr + symbias + || sym.st_value > (opd_shdr->sh_addr + symbias + + opd_shdr->sh_size - sizeof (val64))) + continue; + val64 = *(const uint64_t *) (opd_data->d_buf + sym.st_value + - (opd_shdr->sh_addr + symbias)); + val64 = (elf_getident (elf, NULL)[EI_DATA] == ELFDATA2MSB + ? be64toh (val64) : le64toh (val64)); + assert (dest < pc_table->a + funcs); + dest->sym_from = sym; + dest->st_value_to = val64 + symbias; + dest->name_to = names_dest; + *names_dest++ = '.'; + names_dest = stpcpy (names_dest, symname) + 1; + dest++; + pc_table->nelem++; + } + assert (pc_table->nelem == funcs); + assert (dest == pc_table->a + pc_table->nelem); + assert (names_dest == names + names_size); + qsort (pc_table->a, pc_table->nelem, sizeof (*pc_table->a), compar); +} + +const char * +ppc64_get_func_pc (Ebl *ebl, Dwfl_Module *mod, GElf_Sym *sym) +{ + if (ebl->backend == NULL) + init (ebl, mod); + if (ebl->backend == NULL) + return NULL; + const struct pc_table *pc_table = ebl->backend; + const struct pc_entry *found; + found = bsearch (sym, pc_table->a, pc_table->nelem, sizeof (*pc_table->a), + compar); + if (found == NULL) + return NULL; + sym->st_value = found->st_value_to; + return found->name_to; +} + +void +ppc64_destr (Ebl *ebl) +{ + if (ebl->backend == NULL) + return; + struct pc_table *pc_table = ebl->backend; + free (pc_table); + ebl->backend = NULL; +} |