# This shell script emits a C file. -*- C -*- # Copyright (C) 2002-2018 Free Software Foundation, Inc. # # This file is part of the GNU Binutils. # # 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, write to the Free Software # Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, # MA 02110-1301, USA. # # This file is sourced from elf32.em, and defines extra powerpc64-elf # specific routines. # fragment <the_bfd = bfd_create ("linker stubs", link_info.output_bfd); if (stub_file->the_bfd == NULL || !bfd_set_arch_mach (stub_file->the_bfd, bfd_get_arch (link_info.output_bfd), bfd_get_mach (link_info.output_bfd))) { einfo (_("%F%P: can not create BFD: %E\n")); return; } stub_file->the_bfd->flags |= BFD_LINKER_CREATED; ldlang_add_file (stub_file); params.stub_bfd = stub_file->the_bfd; if (params.save_restore_funcs < 0) params.save_restore_funcs = !bfd_link_relocatable (&link_info); if (!ppc64_elf_init_stub_bfd (&link_info, ¶ms)) einfo (_("%F%P: can not init BFD: %E\n")); } /* Called after opening files but before mapping sections. */ static void ppc_after_open (void) { if (stub_file != NULL && link_info.relro && params.object_in_toc) { /* We have a .toc section that might be written to at run time. Don't put .toc into the .got output section. */ lang_output_section_statement_type *got; got = lang_output_section_find (".got"); if (got != NULL) { lang_statement_union_type *s; for (s = got->children.head; s != NULL; s = s->header.next) if (s->header.type == lang_wild_statement_enum && s->wild_statement.filename == NULL) { struct wildcard_list **i = &s->wild_statement.section_list; while (*i != NULL) if (strcmp ((*i)->spec.name, ".toc") == 0) *i = (*i)->next; else i = &(*i)->next; } /* Instead, .toc input sections will be mapped to the read/write .toc output section. If user scripts don't provide one then we'll lose toc sorting and multi-toc. */ toc_section_name = ".toc"; } } gld${EMULATION_NAME}_after_open (); } /* Move the input section statement at *U which happens to be on LIST to be just before *TO. */ static void move_input_section (lang_statement_list_type *list, lang_statement_union_type **u, lang_statement_union_type **to) { lang_statement_union_type *s = *u; asection *i = s->input_section.section; asection *p, *n; /* Snip the input section from the statement list. If it was the last statement, fix the list tail pointer. */ *u = s->header.next; if (*u == NULL) list->tail = u; /* Add it back in the new position. */ s->header.next = *to; *to = s; if (list->tail == to) list->tail = &s->header.next; /* Trim I off the bfd map_head/map_tail doubly linked lists. */ n = i->map_head.s; p = i->map_tail.s; (p != NULL ? p : i->output_section)->map_head.s = n; (n != NULL ? n : i->output_section)->map_tail.s = p; /* Add I back on in its new position. */ if (s->header.next->header.type == lang_input_section_enum) { n = s->header.next->input_section.section; p = n->map_tail.s; } else { /* If the next statement is not an input section statement then TO must point at the previous input section statement header.next field. */ lang_input_section_type *prev = (lang_input_section_type *) ((char *) to - offsetof (lang_statement_union_type, header.next)); ASSERT (prev->header.type == lang_input_section_enum); p = prev->section; n = p->map_head.s; } i->map_head.s = n; i->map_tail.s = p; (p != NULL ? p : i->output_section)->map_head.s = i; (n != NULL ? n : i->output_section)->map_tail.s = i; } /* Sort input section statements in the linker script tree rooted at LIST so that those whose owning bfd happens to have a section called .init or .fini are placed first. Place any TOC sections referenced by small TOC relocs next, with TOC sections referenced only by bigtoc relocs last. */ static void sort_toc_sections (lang_statement_list_type *list, lang_statement_union_type **ini, lang_statement_union_type **small) { lang_statement_union_type *s, **u; asection *i; u = &list->head; while ((s = *u) != NULL) { switch (s->header.type) { case lang_wild_statement_enum: sort_toc_sections (&s->wild_statement.children, ini, small); break; case lang_group_statement_enum: sort_toc_sections (&s->group_statement.children, ini, small); break; case lang_input_section_enum: i = s->input_section.section; /* Leave the stub_file .got where it is. We put the .got header there. */ if (i->owner == stub_file->the_bfd) break; if (bfd_get_section_by_name (i->owner, ".init") != NULL || bfd_get_section_by_name (i->owner, ".fini") != NULL) { if (ini != NULL && *ini != s) { move_input_section (list, u, ini); if (small == ini) small = &s->header.next; ini = &s->header.next; continue; } if (small == ini) small = &s->header.next; ini = &s->header.next; break; } else if (ini == NULL) ini = u; if (ppc64_elf_has_small_toc_reloc (i)) { if (small != NULL && *small != s) { move_input_section (list, u, small); small = &s->header.next; continue; } small = &s->header.next; } else if (small == NULL) small = u; break; default: break; } u = &s->header.next; } } static void prelim_size_sections (void) { if (expld.phase != lang_mark_phase_enum) { expld.phase = lang_mark_phase_enum; expld.dataseg.phase = exp_seg_none; one_lang_size_sections_pass (NULL, FALSE); /* We must not cache anything from the preliminary sizing. */ lang_reset_memory_regions (); } } static void ppc_before_allocation (void) { if (stub_file != NULL) { if (!no_opd_opt && !ppc64_elf_edit_opd (&link_info)) einfo (_("%X%P: can not edit %s: %E\n"), "opd"); if (ppc64_elf_tls_setup (&link_info) && !no_tls_opt) { /* Size the sections. This is premature, but we want to know the TLS segment layout so that certain optimizations can be done. */ prelim_size_sections (); if (!ppc64_elf_tls_optimize (&link_info)) einfo (_("%X%P: TLS problem %E\n")); } if (!no_toc_opt && !bfd_link_relocatable (&link_info)) { prelim_size_sections (); if (!ppc64_elf_edit_toc (&link_info)) einfo (_("%X%P: can not edit %s: %E\n"), "toc"); } if (!no_toc_sort) { lang_output_section_statement_type *toc_os; toc_os = lang_output_section_find (toc_section_name); if (toc_os != NULL) sort_toc_sections (&toc_os->children, NULL, NULL); } } gld${EMULATION_NAME}_before_allocation (); } struct hook_stub_info { lang_statement_list_type add; asection *input_section; }; /* Traverse the linker tree to find the spot where the stub goes. */ static bfd_boolean hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp) { lang_statement_union_type *l; bfd_boolean ret; for (; (l = *lp) != NULL; lp = &l->header.next) { switch (l->header.type) { case lang_constructors_statement_enum: ret = hook_in_stub (info, &constructor_list.head); if (ret) return ret; break; case lang_output_section_statement_enum: ret = hook_in_stub (info, &l->output_section_statement.children.head); if (ret) return ret; break; case lang_wild_statement_enum: ret = hook_in_stub (info, &l->wild_statement.children.head); if (ret) return ret; break; case lang_group_statement_enum: ret = hook_in_stub (info, &l->group_statement.children.head); if (ret) return ret; break; case lang_input_section_enum: if (l->input_section.section == info->input_section) { /* We've found our section. Insert the stub immediately before its associated input section. */ *lp = info->add.head; *(info->add.tail) = l; return TRUE; } break; case lang_data_statement_enum: case lang_reloc_statement_enum: case lang_object_symbols_statement_enum: case lang_output_statement_enum: case lang_target_statement_enum: case lang_input_statement_enum: case lang_assignment_statement_enum: case lang_padding_statement_enum: case lang_address_statement_enum: case lang_fill_statement_enum: break; default: FAIL (); break; } } return FALSE; } /* Call-back for ppc64_elf_size_stubs. */ /* Create a new stub section, and arrange for it to be linked immediately before INPUT_SECTION. */ static asection * ppc_add_stub_section (const char *stub_sec_name, asection *input_section) { asection *stub_sec; flagword flags; asection *output_section; lang_output_section_statement_type *os; struct hook_stub_info info; flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_KEEP); stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd, stub_sec_name, flags); if (stub_sec == NULL || !bfd_set_section_alignment (stub_file->the_bfd, stub_sec, (params.plt_stub_align > 5 ? params.plt_stub_align : params.plt_stub_align < -5 ? -params.plt_stub_align : 5))) goto err_ret; output_section = input_section->output_section; os = lang_output_section_get (output_section); info.input_section = input_section; lang_list_init (&info.add); lang_add_section (&info.add, stub_sec, NULL, os); if (info.add.head == NULL) goto err_ret; if (hook_in_stub (&info, &os->children.head)) return stub_sec; err_ret: einfo (_("%X%P: can not make stub section: %E\n")); return NULL; } /* Another call-back for ppc64_elf_size_stubs. */ static void ppc_layout_sections_again (void) { /* If we have changed sizes of the stub sections, then we need to recalculate all the section offsets. This may mean we need to add even more stubs. */ gld${EMULATION_NAME}_map_segments (TRUE); if (!bfd_link_relocatable (&link_info)) ppc64_elf_set_toc (&link_info, link_info.output_bfd); need_laying_out = -1; } static void build_toc_list (lang_statement_union_type *statement) { if (statement->header.type == lang_input_section_enum) { asection *i = statement->input_section.section; if (i->sec_info_type != SEC_INFO_TYPE_JUST_SYMS && (i->flags & SEC_EXCLUDE) == 0 && i->output_section == toc_section) { if (!ppc64_elf_next_toc_section (&link_info, i)) einfo (_("%X%P: linker script separates .got and .toc\n")); } } } static void build_section_lists (lang_statement_union_type *statement) { if (statement->header.type == lang_input_section_enum) { asection *i = statement->input_section.section; if (!((lang_input_statement_type *) i->owner->usrdata)->flags.just_syms && (i->flags & SEC_EXCLUDE) == 0 && i->output_section != NULL && i->output_section->owner == link_info.output_bfd) { if (!ppc64_elf_next_input_section (&link_info, i)) einfo (_("%X%P: can not size stub section: %E\n")); } } } /* Call the back-end function to set TOC base after we have placed all the sections. */ static void gld${EMULATION_NAME}_after_allocation (void) { int ret; /* If generating a relocatable output file, then we don't have any stubs. */ if (stub_file != NULL && !bfd_link_relocatable (&link_info)) { ret = ppc64_elf_setup_section_lists (&link_info); if (ret < 0) einfo (_("%X%P: can not size stub section: %E\n")); else { ppc64_elf_start_multitoc_partition (&link_info); if (!params.no_multi_toc) { toc_section = bfd_get_section_by_name (link_info.output_bfd, toc_section_name); if (toc_section != NULL) lang_for_each_statement (build_toc_list); } if (ppc64_elf_layout_multitoc (&link_info) && !params.no_multi_toc && toc_section != NULL) lang_for_each_statement (build_toc_list); ppc64_elf_finish_multitoc_partition (&link_info); lang_for_each_statement (build_section_lists); if (!ppc64_elf_check_init_fini (&link_info)) einfo (_("%P: .init/.fini fragments use differing TOC pointers\n")); /* Call into the BFD backend to do the real work. */ if (!ppc64_elf_size_stubs (&link_info)) einfo (_("%X%P: can not size stub section: %E\n")); } } /* We can't parse and merge .eh_frame until the glink .eh_frame has been generated. Otherwise the glink .eh_frame CIE won't be merged with other CIEs, and worse, the glink .eh_frame FDEs won't be listed in .eh_frame_hdr. */ ret = bfd_elf_discard_info (link_info.output_bfd, &link_info); if (ret < 0) { einfo (_("%X%P: .eh_frame/.stab edit: %E\n")); return; } else if (ret > 0) need_laying_out = 1; /* Call map_segments regardless of the state of need_laying_out. need_laying_out set to -1 means we have just laid everything out, but ppc64_elf_size_stubs strips .branch_lt and .eh_frame if unneeded, after ppc_layout_sections_again. Another call removes these sections from the segment map. Their presence is innocuous except for confusing ELF_SECTION_IN_SEGMENT. */ gld${EMULATION_NAME}_map_segments (need_laying_out > 0); if (need_laying_out != -1 && !bfd_link_relocatable (&link_info)) ppc64_elf_set_toc (&link_info, link_info.output_bfd); } /* Final emulation specific call. */ static void gld${EMULATION_NAME}_finish (void) { char *msg = NULL; char *line, *endline; /* e_entry on PowerPC64 points to the function descriptor for _start. If _start is missing, default to the first function descriptor in the .opd section. */ if (stub_file != NULL && (elf_elfheader (link_info.output_bfd)->e_flags & EF_PPC64_ABI) == 1) entry_section = ".opd"; if (params.emit_stub_syms < 0) params.emit_stub_syms = 1; if (stub_file != NULL && !bfd_link_relocatable (&link_info) && !ppc64_elf_build_stubs (&link_info, config.stats ? &msg : NULL)) einfo (_("%X%P: can not build stubs: %E\n")); fflush (stdout); for (line = msg; line != NULL; line = endline) { endline = strchr (line, '\n'); if (endline != NULL) *endline++ = '\0'; fprintf (stderr, "%s: %s\n", program_name, line); } fflush (stderr); if (msg != NULL) free (msg); finish_default (); } /* Add a pattern matching ".foo" for every "foo" in a version script. The reason for doing this is that many shared library version scripts export a selected set of functions or data symbols, forcing others local. eg. . VERS_1 { . global: . this; that; some; thing; . local: . *; . }; To make the above work for PowerPC64, we need to export ".this", ".that" and so on, otherwise only the function descriptor syms are exported. Lack of an exported function code sym may cause a definition to be pulled in from a static library. */ static struct bfd_elf_version_expr * gld${EMULATION_NAME}_new_vers_pattern (struct bfd_elf_version_expr *entry) { struct bfd_elf_version_expr *dot_entry; unsigned int len; char *dot_pat; if (!dotsyms || entry->pattern[0] == '.' || (!entry->literal && entry->pattern[0] == '*')) return entry; dot_entry = xmalloc (sizeof *dot_entry); *dot_entry = *entry; dot_entry->next = entry; len = strlen (entry->pattern) + 2; dot_pat = xmalloc (len); dot_pat[0] = '.'; memcpy (dot_pat + 1, entry->pattern, len - 1); dot_entry->pattern = dot_pat; dot_entry->script = 1; return dot_entry; } /* Avoid processing the fake stub_file in vercheck, stat_needed and check_needed routines. */ static void (*real_func) (lang_input_statement_type *); static void ppc_for_each_input_file_wrapper (lang_input_statement_type *l) { if (l != stub_file) (*real_func) (l); } static void ppc_lang_for_each_input_file (void (*func) (lang_input_statement_type *)) { real_func = func; lang_for_each_input_file (&ppc_for_each_input_file_wrapper); } #define lang_for_each_input_file ppc_lang_for_each_input_file EOF if grep -q 'ld_elf32_spu_emulation' ldemul-list.h; then fragment <] Align PLT call stubs to fit cache lines.\n" )); fprintf (file, _("\ --no-plt-align Dont'\''t align individual PLT call stubs.\n" )); fprintf (file, _("\ --plt-localentry Optimize calls to ELFv2 localentry:0 functions.\n" )); fprintf (file, _("\ --no-plt-localentry Don'\''t optimize ELFv2 calls.\n" )); fprintf (file, _("\ --emit-stub-syms Label linker stubs with a symbol.\n" )); fprintf (file, _("\ --no-emit-stub-syms Don'\''t label linker stubs with a symbol.\n" )); fprintf (file, _("\ --dotsyms For every version pattern \"foo\" in a version\n\ script, add \".foo\" so that function code\n\ symbols are treated the same as function\n\ descriptor symbols. Defaults to on.\n" )); fprintf (file, _("\ --no-dotsyms Don'\''t do anything special in version scripts.\n" )); fprintf (file, _("\ --save-restore-funcs Provide register save and restore routines used\n\ by gcc -Os code. Defaults to on for normal\n\ final link, off for ld -r.\n" )); fprintf (file, _("\ --no-save-restore-funcs Don'\''t provide these routines.\n" )); fprintf (file, _("\ --no-tls-optimize Don'\''t try to optimize TLS accesses.\n" )); fprintf (file, _("\ --tls-get-addr-optimize Force use of special __tls_get_addr call.\n" )); fprintf (file, _("\ --no-tls-get-addr-optimize Don'\''t use a special __tls_get_addr call.\n" )); fprintf (file, _("\ --no-opd-optimize Don'\''t optimize the OPD section.\n" )); fprintf (file, _("\ --no-toc-optimize Don'\''t optimize the TOC section.\n" )); fprintf (file, _("\ --no-multi-toc Disallow automatic multiple toc sections.\n" )); fprintf (file, _("\ --no-toc-sort Don'\''t sort TOC and GOT sections.\n" )); fprintf (file, _("\ --non-overlapping-opd Canonicalize .opd, so that there are no\n\ overlapping .opd entries.\n" )); ' PARSE_AND_LIST_ARGS_CASES=${PARSE_AND_LIST_ARGS_CASES}' case OPTION_STUBGROUP_SIZE: { const char *end; params.group_size = bfd_scan_vma (optarg, &end, 0); if (*end) einfo (_("%P%F: invalid number `%s'\''\n"), optarg); } break; case OPTION_PLT_STATIC_CHAIN: params.plt_static_chain = 1; break; case OPTION_NO_PLT_STATIC_CHAIN: params.plt_static_chain = 0; break; case OPTION_PLT_THREAD_SAFE: params.plt_thread_safe = 1; break; case OPTION_NO_PLT_THREAD_SAFE: params.plt_thread_safe = 0; break; case OPTION_SPECULATE_INDIRECT_JUMPS: params.speculate_indirect_jumps = 1; break; case OPTION_NO_SPECULATE_INDIRECT_JUMPS: params.speculate_indirect_jumps = 0; break; case OPTION_PLT_ALIGN: if (optarg != NULL) { char *end; long val = strtol (optarg, &end, 0); if (*end || (unsigned long) val + 8 > 16) einfo (_("%P%F: invalid --plt-align `%s'\''\n"), optarg); params.plt_stub_align = val; } else params.plt_stub_align = 5; break; case OPTION_NO_PLT_ALIGN: params.plt_stub_align = 0; break; case OPTION_PLT_LOCALENTRY: params.plt_localentry0 = 1; break; case OPTION_NO_PLT_LOCALENTRY: params.plt_localentry0 = 0; break; case OPTION_STUBSYMS: params.emit_stub_syms = 1; break; case OPTION_NO_STUBSYMS: params.emit_stub_syms = 0; break; case OPTION_DOTSYMS: dotsyms = 1; break; case OPTION_NO_DOTSYMS: dotsyms = 0; break; case OPTION_SAVRES: params.save_restore_funcs = 1; break; case OPTION_NO_SAVRES: params.save_restore_funcs = 0; break; case OPTION_NO_TLS_OPT: no_tls_opt = 1; break; case OPTION_TLS_GET_ADDR_OPT: params.tls_get_addr_opt = 1; break; case OPTION_NO_TLS_GET_ADDR_OPT: params.tls_get_addr_opt = 0; break; case OPTION_NO_OPD_OPT: no_opd_opt = 1; break; case OPTION_NO_TOC_OPT: no_toc_opt = 1; break; case OPTION_NO_MULTI_TOC: params.no_multi_toc = 1; break; case OPTION_NO_TOC_SORT: no_toc_sort = 1; break; case OPTION_NON_OVERLAPPING_OPD: params.non_overlapping_opd = 1; break; case OPTION_TRADITIONAL_FORMAT: no_tls_opt = 1; params.tls_get_addr_opt = 0; no_opd_opt = 1; no_toc_opt = 1; params.no_multi_toc = 1; no_toc_sort = 1; params.plt_static_chain = 1; return FALSE; ' # Put these extra ppc64elf routines in ld_${EMULATION_NAME}_emulation # LDEMUL_NEW_VERS_PATTERN=gld${EMULATION_NAME}_new_vers_pattern LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=ppc_create_output_section_statements LDEMUL_AFTER_OPEN=ppc_after_open LDEMUL_BEFORE_ALLOCATION=ppc_before_allocation LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation LDEMUL_FINISH=gld${EMULATION_NAME}_finish