diff options
Diffstat (limited to 'bfd')
| -rw-r--r-- | bfd/ChangeLog | 12 | ||||
| -rw-r--r-- | bfd/xcofflink.c | 232 |
2 files changed, 167 insertions, 77 deletions
diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 3a8c0e6..0bd0d16 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,5 +1,17 @@ 2009-03-14 Richard Sandiford <r.sandiford@uk.ibm.com> + * xcofflink.c: (xcoff_mark_symbol): Mark the TOC section when + creating a descriptor. + (xcoff_sweep): Don't mark toc_section unless it's needed. + (bfd_xcoff_size_dynamic_sections): Skip the toc_section + when marking every bfd. + (xcoff_link_input_bfd): Skip all TOC anchors. + (xcoff_toc_section_p, xcoff_find_tc0): New functions. + (_bfd_xcoff_bfd_final_link): Don't set the output bfd's TOC anchor + to -1; call xcoff_find_tc0 instead. + +2009-03-14 Richard Sandiford <r.sandiford@uk.ibm.com> + * libcoff-in.h (xcoff_section_tdata): Update commentary. * libcoff.h: Regenerate. * xcofflink.c (xcoff_link_add_symbols): Set the csect of XTY_ER diff --git a/bfd/xcofflink.c b/bfd/xcofflink.c index d12ed51..c6bdc9f 100644 --- a/bfd/xcofflink.c +++ b/bfd/xcofflink.c @@ -2331,6 +2331,11 @@ xcoff_mark_symbol (struct bfd_link_info *info, struct xcoff_link_hash_entry *h) if (!xcoff_mark_symbol (info, h->descriptor)) return FALSE; + /* Mark the TOC section, so that we get an anchor + to relocate against. */ + if (!xcoff_mark (info, xcoff_hash_table (info)->toc_section)) + return FALSE; + /* We handle writing out the contents of the descriptor in xcoff_write_global_symbol. */ } @@ -2590,7 +2595,6 @@ xcoff_sweep (struct bfd_link_info *info) || o == xcoff_hash_table (info)->debug_section || o == xcoff_hash_table (info)->loader_section || o == xcoff_hash_table (info)->linkage_section - || o == xcoff_hash_table (info)->toc_section || o == xcoff_hash_table (info)->descriptor_section || strcmp (o->name, ".debug") == 0) o->flags |= SEC_MARK; @@ -3126,7 +3130,12 @@ bfd_xcoff_size_dynamic_sections (bfd *output_bfd, for (o = sub->sections; o != NULL; o = o->next) { - if ((o->flags & SEC_MARK) == 0) + /* We shouldn't unconditionaly mark the TOC section. + The output file should only have a TOC if either + (a) one of the input files did or (b) we end up + creating TOC references as part of the link process. */ + if (o != xcoff_hash_table (info)->toc_section + && (o->flags & SEC_MARK) == 0) { if (! xcoff_mark (info, o)) goto error_return; @@ -3504,7 +3513,6 @@ xcoff_link_input_bfd (struct xcoff_final_link_info *finfo, union internal_auxent aux; int smtyp = 0; bfd_boolean skip; - bfd_boolean require; int add; bfd_coff_swap_sym_in (input_bfd, (void *) esym, (void *) isymp); @@ -3623,7 +3631,6 @@ xcoff_link_input_bfd (struct xcoff_final_link_info *finfo, *indexp = -1; skip = FALSE; - require = FALSE; add = 1 + isym.n_numaux; /* If we are skipping this csect, we want to skip this symbol. */ @@ -3644,75 +3651,11 @@ xcoff_link_input_bfd (struct xcoff_final_link_info *finfo, && isymp->n_sclass == C_STAT) skip = TRUE; - /* We skip all but the first TOC anchor. */ + /* We generate the TOC anchor separately. */ if (! skip && isymp->n_sclass == C_HIDEXT && aux.x_csect.x_smclas == XMC_TC0) - { - if (finfo->toc_symindx != -1) - skip = TRUE; - else - { - bfd_vma tocval, tocend; - bfd *inp; - - tocval = ((*csectpp)->output_section->vma - + (*csectpp)->output_offset - + isym.n_value - - (*csectpp)->vma); - - /* We want to find out if tocval is a good value to use - as the TOC anchor--that is, whether we can access all - of the TOC using a 16 bit offset from tocval. This - test assumes that the TOC comes at the end of the - output section, as it does in the default linker - script. */ - tocend = ((*csectpp)->output_section->vma - + (*csectpp)->output_section->size); - for (inp = finfo->info->input_bfds; - inp != NULL; - inp = inp->link_next) - { - - for (o = inp->sections; o != NULL; o = o->next) - if (strcmp (o->name, ".tocbss") == 0) - { - bfd_vma new_toc_end; - new_toc_end = (o->output_section->vma - + o->output_offset - + o->size); - if (new_toc_end > tocend) - tocend = new_toc_end; - } - - } - - if (tocval + 0x10000 < tocend) - { - (*_bfd_error_handler) - (_("TOC overflow: 0x%lx > 0x10000; try -mminimal-toc when compiling"), - (unsigned long) (tocend - tocval)); - bfd_set_error (bfd_error_file_too_big); - return FALSE; - } - - if (tocval + 0x8000 < tocend) - { - bfd_vma tocadd; - - tocadd = tocend - (tocval + 0x8000); - tocval += tocadd; - isym.n_value += tocadd; - } - - finfo->toc_symindx = output_index; - xcoff_data (finfo->output_bfd)->toc = tocval; - xcoff_data (finfo->output_bfd)->sntoc = - (*csectpp)->output_section->target_index; - require = TRUE; - - } - } + skip = TRUE; /* If we are stripping all symbols, we want to skip this one. */ if (! skip @@ -3781,12 +3724,6 @@ xcoff_link_input_bfd (struct xcoff_final_link_info *finfo, skip = TRUE; } - /* We can not skip the first TOC anchor. */ - if (skip - && require - && finfo->info->strip != strip_all) - skip = FALSE; - /* We now know whether we are to skip this symbol or not. */ if (! skip) { @@ -4616,6 +4553,144 @@ xcoff_sort_relocs (const void * p1, const void * p2) return 0; } +/* Return true if section SEC is a TOC section. */ + +static inline bfd_boolean +xcoff_toc_section_p (asection *sec) +{ + const char *name; + + name = sec->name; + if (name[0] == '.' && name[1] == 't') + { + if (name[2] == 'c') + { + if (name[3] == '0' && name[4] == 0) + return TRUE; + if (name[3] == 0) + return TRUE; + } + if (name[2] == 'd' && name[3] == 0) + return TRUE; + } + return FALSE; +} + +/* See if the link requires a TOC (it usually does!). If so, find a + good place to put the TOC anchor csect, and write out the associated + symbol. */ + +static bfd_boolean +xcoff_find_tc0 (bfd *output_bfd, struct xcoff_final_link_info *finfo) +{ + bfd_vma toc_start, toc_end, start, end, best_address; + asection *sec; + bfd *input_bfd; + int section_index; + struct internal_syment irsym; + union internal_auxent iraux; + file_ptr pos; + size_t size; + + /* Set [TOC_START, TOC_END) to the range of the TOC. Record the + index of a csect at the beginning of the TOC. */ + toc_start = ~(bfd_vma) 0; + toc_end = 0; + section_index = -1; + for (input_bfd = finfo->info->input_bfds; + input_bfd != NULL; + input_bfd = input_bfd->link_next) + for (sec = input_bfd->sections; sec != NULL; sec = sec->next) + if ((sec->flags & SEC_MARK) != 0 && xcoff_toc_section_p (sec)) + { + start = sec->output_section->vma + sec->output_offset; + if (toc_start > start) + { + toc_start = start; + section_index = sec->output_section->target_index; + } + + end = start + sec->size; + if (toc_end < end) + toc_end = end; + } + + /* There's no need for a TC0 symbol if we don't have a TOC. */ + if (toc_end < toc_start) + { + xcoff_data (output_bfd)->toc = toc_start; + return TRUE; + } + + if (toc_end - toc_start < 0x8000) + /* Every TOC csect can be accessed from TOC_START. */ + best_address = toc_start; + else + { + /* Find the lowest TOC csect that is still within range of TOC_END. */ + best_address = toc_end; + for (input_bfd = finfo->info->input_bfds; + input_bfd != NULL; + input_bfd = input_bfd->link_next) + for (sec = input_bfd->sections; sec != NULL; sec = sec->next) + if ((sec->flags & SEC_MARK) != 0 && xcoff_toc_section_p (sec)) + { + start = sec->output_section->vma + sec->output_offset; + if (start < best_address + && start + 0x8000 >= toc_end) + { + best_address = start; + section_index = sec->output_section->target_index; + } + } + + /* Make sure that the start of the TOC is also within range. */ + if (best_address > toc_start + 0x8000) + { + (*_bfd_error_handler) + (_("TOC overflow: 0x%lx > 0x10000; try -mminimal-toc " + "when compiling"), + (unsigned long) (toc_end - toc_start)); + bfd_set_error (bfd_error_file_too_big); + return FALSE; + } + } + + /* Record the chosen TOC value. */ + finfo->toc_symindx = obj_raw_syment_count (output_bfd); + xcoff_data (output_bfd)->toc = best_address; + xcoff_data (output_bfd)->sntoc = section_index; + + /* Fill out the TC0 symbol. */ + if (!bfd_xcoff_put_symbol_name (output_bfd, finfo->strtab, &irsym, "TOC")) + return FALSE; + irsym.n_value = best_address; + irsym.n_scnum = section_index; + irsym.n_sclass = C_HIDEXT; + irsym.n_type = T_NULL; + irsym.n_numaux = 1; + bfd_coff_swap_sym_out (output_bfd, &irsym, finfo->outsyms); + + /* Fill out the auxillary csect information. */ + memset (&iraux, 0, sizeof iraux); + iraux.x_csect.x_smtyp = XTY_SD; + iraux.x_csect.x_smclas = XMC_TC0; + iraux.x_csect.x_scnlen.l = 0; + bfd_coff_swap_aux_out (output_bfd, &iraux, T_NULL, C_HIDEXT, 0, 1, + finfo->outsyms + bfd_coff_symesz (output_bfd)); + + /* Write the contents to the file. */ + pos = obj_sym_filepos (output_bfd); + pos += obj_raw_syment_count (output_bfd) * bfd_coff_symesz (output_bfd); + size = 2 * bfd_coff_symesz (output_bfd); + if (bfd_seek (output_bfd, pos, SEEK_SET) != 0 + || bfd_bwrite (finfo->outsyms, size, output_bfd) != size) + return FALSE; + obj_raw_syment_count (output_bfd) += 2; + + return TRUE; +} + /* Write out a non-XCOFF global symbol. */ static bfd_boolean @@ -5692,7 +5767,10 @@ _bfd_xcoff_bfd_final_link (bfd *abfd, struct bfd_link_info *info) goto error_return; obj_raw_syment_count (abfd) = 0; - xcoff_data (abfd)->toc = (bfd_vma) -1; + + /* Find a TOC symbol, if we need one. */ + if (!xcoff_find_tc0 (abfd, &finfo)) + goto error_return; /* We now know the position of everything in the file, except that we don't know the size of the symbol table and therefore we don't |