From 9c1d81c1026e37bc3ee9061ae245f195eba961f5 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Wed, 1 May 2002 02:34:54 +0000 Subject: [PATCH] Long branch stubs, multiple stub sections. * emultempl/ppc64elf.em: Include ldctor.h. (stub_file): New var. (group_size): New var. (ppc_create_output_section_statements): New function. (struct hook_stub_info): New. (hook_in_stub): New function. (ppc_add_stub_section): New function. (ppc_layout_sections_again): New function. (build_section_lists): New function. (gld${EMULATION_NAME}_finish): Rewrite. (real_func): New var. (ppc_for_each_input_file_wrapper): New function. (ppc_lang_for_each_input_file): New function. (lang_for_each_input_file): Define. (PARSE_AND_LIST_PROLOGUE): Define. (PARSE_AND_LIST_LONGOPTS): Define. (PARSE_AND_LIST_OPTIONS): Define. (PARSE_AND_LIST_ARGS_CASES): Define. (LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS): Define. --- ld/ChangeLog | 23 +++ ld/emultempl/ppc64elf.em | 317 +++++++++++++++++++++++++++++++++++---- 2 files changed, 314 insertions(+), 26 deletions(-) diff --git a/ld/ChangeLog b/ld/ChangeLog index 646c43066ee..f91ac7087cc 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,26 @@ +2002-05-01 Alan Modra + + Long branch stubs, multiple stub sections. + * emultempl/ppc64elf.em: Include ldctor.h. + (stub_file): New var. + (group_size): New var. + (ppc_create_output_section_statements): New function. + (struct hook_stub_info): New. + (hook_in_stub): New function. + (ppc_add_stub_section): New function. + (ppc_layout_sections_again): New function. + (build_section_lists): New function. + (gld${EMULATION_NAME}_finish): Rewrite. + (real_func): New var. + (ppc_for_each_input_file_wrapper): New function. + (ppc_lang_for_each_input_file): New function. + (lang_for_each_input_file): Define. + (PARSE_AND_LIST_PROLOGUE): Define. + (PARSE_AND_LIST_LONGOPTS): Define. + (PARSE_AND_LIST_OPTIONS): Define. + (PARSE_AND_LIST_ARGS_CASES): Define. + (LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS): Define. + 2002-04-30 Tom Rix * emultempl/aix.em (gld*_parse_arge, gld*_before_allocation): Add diff --git a/ld/emultempl/ppc64elf.em b/ld/emultempl/ppc64elf.em index 65b824e7345..a96bb222498 100644 --- a/ld/emultempl/ppc64elf.em +++ b/ld/emultempl/ppc64elf.em @@ -23,12 +23,199 @@ # cat >>e${EMULATION_NAME}.c <the_bfd = bfd_create ("linker stubs", output_bfd); + if (stub_file->the_bfd == NULL + || !bfd_set_arch_mach (stub_file->the_bfd, + bfd_get_arch (output_bfd), + bfd_get_mach (output_bfd))) + { + einfo ("%X%P: can not create BFD %E\n"); + return; + } + + ldlang_add_file (stub_file); +} + + +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 boolean hook_in_stub + PARAMS ((struct hook_stub_info *, lang_statement_union_type **)); + +static boolean +hook_in_stub (info, lp) + struct hook_stub_info *info; + lang_statement_union_type **lp; +{ + lang_statement_union_type *l; + 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 (stub_sec_name, input_section) + const char *stub_sec_name; + asection *input_section; +{ + asection *stub_sec; + flagword flags; + asection *output_section; + const char *secname; + lang_output_section_statement_type *os; + struct hook_stub_info info; + + stub_sec = bfd_make_section_anyway (stub_file->the_bfd, stub_sec_name); + if (stub_sec == NULL) + goto err_ret; + + flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE + | SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP); + if (!bfd_set_section_flags (stub_file->the_bfd, stub_sec, flags)) + goto err_ret; + + output_section = input_section->output_section; + secname = bfd_get_section_name (output_section->owner, output_section); + os = lang_output_section_find (secname); + + info.input_section = input_section; + lang_list_init (&info.add); + lang_add_section (&info.add, stub_sec, os, stub_file); + + 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 () +{ + /* 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. */ + need_laying_out = 0; + + lang_reset_memory_regions (); + + /* Resize the sections. */ + lang_size_sections (stat_ptr->head, abs_output_section, + &stat_ptr->head, 0, (bfd_vma) 0, NULL); + + /* Recalculate TOC base. */ + ldemul_after_allocation (); + + /* Do the assignments again. */ + lang_do_assignments (stat_ptr->head, abs_output_section, + (fill_type *) 0, (bfd_vma) 0); +} + /* Call the back-end function to set TOC base after we have placed all the sections. */ @@ -39,14 +226,26 @@ gld${EMULATION_NAME}_after_allocation () einfo ("%X%P: can not set TOC base: %E\n"); } -/* Final emulation specific call. PowerPC64 has 24 byte .plt entries, - and needs different call stubs for any entries that cross a 64k - boundary relative to the TOC. That means we need to wait until all - sections have been laid out to initialise the stubs. */ + +static void +build_section_lists (statement) + lang_statement_union_type *statement; +{ + if (statement->header.type == lang_input_section_enum + && !statement->input_section.ifile->just_syms_flag) + { + ppc64_elf_next_input_section (output_bfd, &link_info, + statement->input_section.section); + } +} + +/* Final emulation specific call. */ static void gld${EMULATION_NAME}_finish () { + int ret; + /* e_entry on PowerPC64 points to the function descriptor for _start. If _start is missing, default to the first function descriptor in the .opd section. */ @@ -60,47 +259,113 @@ gld${EMULATION_NAME}_finish () /* bfd_elf64_discard_info just plays with debugging sections, ie. doesn't affect any code, so we can delay resizing the sections. It's likely we'll resize everything in the process of - adjusting stub sizes. */ + adding stubs. */ if (bfd_elf${ELFSIZE}_discard_info (output_bfd, &link_info)) need_laying_out = 1; - while (1) + ret = ppc64_elf_setup_section_lists (output_bfd, &link_info); + if (ret != 0) { + if (ret < 0) + { + einfo ("%X%P: can not size stub section: %E\n"); + return; + } + + lang_for_each_statement (build_section_lists); + /* Call into the BFD backend to do the real work. */ - if (! ppc64_elf_size_stubs (output_bfd, &link_info, &need_laying_out)) + if (!ppc64_elf_size_stubs (output_bfd, + stub_file->the_bfd, + &link_info, + group_size, + &ppc_add_stub_section, + &ppc_layout_sections_again)) { einfo ("%X%P: can not size stub section: %E\n"); return; } + } - if (!need_laying_out) - break; + if (need_laying_out) + ppc_layout_sections_again (); - /* If we have changed the size of the stub section, then we need - to recalculate all the section offsets. After this, we may - need to adjust the stub size again. */ - need_laying_out = 0; + if (stub_file->the_bfd->sections != NULL) + { + if (!ppc64_elf_build_stubs (&link_info)) + einfo ("%X%P: can not build stubs: %E\n"); + } +} - lang_reset_memory_regions (); - /* Resize the sections. */ - lang_size_sections (stat_ptr->head, abs_output_section, - &stat_ptr->head, 0, (bfd_vma) 0, NULL); +/* Avoid processing the fake stub_file in vercheck, stat_needed and + check_needed routines. */ - /* Recalculate TOC base. */ - ldemul_after_allocation (); +static void ppc_for_each_input_file_wrapper + PARAMS ((lang_input_statement_type *)); +static void ppc_lang_for_each_input_file + PARAMS ((void (*) (lang_input_statement_type *))); - /* Do the assignments again. */ - lang_do_assignments (stat_ptr->head, abs_output_section, - (fill_type *) 0, (bfd_vma) 0); - } +static void (*real_func) PARAMS ((lang_input_statement_type *)); - if (! ppc64_elf_build_stubs (output_bfd, &link_info)) - einfo ("%X%P: can not build stubs: %E\n"); +static void ppc_for_each_input_file_wrapper (l) + lang_input_statement_type *l; +{ + if (l != stub_file) + (*real_func) (l); } + +static void +ppc_lang_for_each_input_file (func) + void (*func) PARAMS ((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 +# Define some shell vars to insert bits of code into the standard elf +# parse_args and list_options functions. +# +PARSE_AND_LIST_PROLOGUE=' +#define OPTION_STUBGROUP_SIZE 301 +' + +# The options are repeated below so that no abbreviations are allowed. +# Otherwise -s matches stub-group-size +PARSE_AND_LIST_LONGOPTS=' + { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE }, + { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE }, +' + +PARSE_AND_LIST_OPTIONS=' + fprintf (file, _("\ + --stub-group-size=N Maximum size of a group of input sections that can be\n\ + handled by one stub section. A negative value\n\ + locates all stubs before their branches (with a\n\ + group size of -N), while a positive value allows\n\ + two groups of input sections, one before, and one\n\ + after each stub section. Values of +/-1 indicate\n\ + the linker should choose suitable defaults.\n" + )); +' + +PARSE_AND_LIST_ARGS_CASES=' + case OPTION_STUBGROUP_SIZE: + { + const char *end; + group_size = bfd_scan_vma (optarg, &end, 0); + if (*end) + einfo (_("%P%F: invalid number `%s'\''\n"), optarg); + } + break; +' + # Put these extra ppc64elf routines in ld_${EMULATION_NAME}_emulation # LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation LDEMUL_FINISH=gld${EMULATION_NAME}_finish +LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=ppc_create_output_section_statements -- 2.30.2