1# This shell script emits a C file. -*- C -*- 2# Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 3# Free Software Foundation, Inc. 4# 5# This file is part of the GNU Binutils. 6# 7# This program is free software; you can redistribute it and/or modify 8# it under the terms of the GNU General Public License as published by 9# the Free Software Foundation; either version 3 of the License, or 10# (at your option) any later version. 11# 12# This program is distributed in the hope that it will be useful, 13# but WITHOUT ANY WARRANTY; without even the implied warranty of 14# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15# GNU General Public License for more details. 16# 17# You should have received a copy of the GNU General Public License 18# along with this program; if not, write to the Free Software 19# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 20# MA 02110-1301, USA. 21# 22 23# This file is sourced from generic.em. 24 25fragment <<EOF 26/* Need to have this macro defined before mmix-elfnmmo, which uses the 27 name for the before_allocation function, defined in ldemul.c (for 28 the mmo "emulation") or in elf32.em (for the elf64mmix 29 "emulation"). */ 30#define gldmmo_before_allocation before_allocation_default 31 32/* We include this header *not* because we expect to handle ELF here 33 but because we re-use the map_segments function in elf-generic.em, 34 a file which is rightly somewhat ELF-centric. But this is only to 35 get a weird testcase right; ld-mmix/bpo-22, forcing ELF to be 36 output from the mmo emulation: -m mmo --oformat elf64-mmix! */ 37#include "elf-bfd.h" 38 39static void gld${EMULATION_NAME}_after_allocation (void); 40EOF 41 42source_em ${srcdir}/emultempl/elf-generic.em 43source_em ${srcdir}/emultempl/mmix-elfnmmo.em 44 45fragment <<EOF 46 47/* Place an orphan section. We use this to put random SEC_CODE or 48 SEC_READONLY sections right after MMO_TEXT_SECTION_NAME. Much borrowed 49 from elf32.em. */ 50 51static lang_output_section_statement_type * 52mmo_place_orphan (asection *s, 53 const char *secname, 54 int constraint ATTRIBUTE_UNUSED) 55{ 56 static struct 57 { 58 flagword nonzero_flags; 59 struct orphan_save orphansave; 60 } holds[] = 61 { 62 { 63 SEC_CODE | SEC_READONLY, 64 { 65 MMO_TEXT_SECTION_NAME, 66 SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE, 67 0, 0, 0, 0 68 } 69 }, 70 { 71 SEC_LOAD | SEC_DATA, 72 { 73 MMO_DATA_SECTION_NAME, 74 SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_DATA, 75 0, 0, 0, 0 76 } 77 }, 78 { 79 SEC_ALLOC, 80 { 81 ".bss", 82 SEC_ALLOC, 83 0, 0, 0, 0 84 } 85 } 86 }; 87 88 struct orphan_save *place = NULL; 89 lang_output_section_statement_type *after; 90 lang_output_section_statement_type *os; 91 size_t i; 92 93 /* We have nothing to say for anything other than a final link or 94 for sections that are excluded. */ 95 if (link_info.relocatable 96 || (s->flags & SEC_EXCLUDE) != 0) 97 return NULL; 98 99 os = lang_output_section_find (secname); 100 101 /* We have an output section by this name. Place the section inside it 102 (regardless of whether the linker script lists it as input). */ 103 if (os != NULL) 104 { 105 lang_add_section (&os->children, s, NULL, os); 106 return os; 107 } 108 109 /* Check for matching section type flags for sections we care about. 110 A section without contents can have SEC_LOAD == 0, but we still 111 want it attached to a sane section so the symbols appear as 112 expected. */ 113 if ((s->flags & (SEC_ALLOC | SEC_READONLY)) != SEC_READONLY) 114 for (i = 0; i < sizeof (holds) / sizeof (holds[0]); i++) 115 if ((s->flags & holds[i].nonzero_flags) != 0) 116 { 117 place = &holds[i].orphansave; 118 if (place->os == NULL) 119 place->os = lang_output_section_find (place->name); 120 break; 121 } 122 123 if (place == NULL) 124 { 125 /* For other combinations, we have to give up, except we make 126 sure not to place the orphan section after the 127 linker-generated register section; that'd make it continue 128 the reg section and we never want that to happen for orphan 129 sections. */ 130 lang_output_section_statement_type *before; 131 lang_output_section_statement_type *lookup; 132 static struct orphan_save hold_nonreg = 133 { 134 NULL, 135 SEC_READONLY, 136 0, 0, 0, 0 137 }; 138 139 if (hold_nonreg.os == NULL) 140 { 141 before = lang_output_section_find (MMIX_REG_CONTENTS_SECTION_NAME); 142 143 /* If we have no such section, all fine; we don't care where 144 it's placed. */ 145 if (before == NULL) 146 return NULL; 147 148 /* We have to find the oss before this one, so we can use that as 149 "after". */ 150 for (lookup = &lang_output_section_statement.head->output_section_statement; 151 lookup != NULL && lookup->next != before; 152 lookup = lookup->next) 153 ; 154 155 hold_nonreg.os = lookup; 156 } 157 158 place = &hold_nonreg; 159 } 160 161 after = place->os; 162 if (after == NULL) 163 return NULL; 164 165 /* If there's an output section by *this* name, we'll use it, regardless 166 of actual section flags, in contrast to what's done in elf32.em. */ 167 os = lang_insert_orphan (s, secname, 0, after, place, NULL, NULL); 168 169 return os; 170} 171 172/* Remove the spurious settings of SEC_RELOC that make it to the output at 173 link time. We are as confused as elflink.h:elf_bfd_final_link, and 174 paper over the bug similarly. */ 175 176static void 177mmo_wipe_sec_reloc_flag (bfd *abfd, asection *sec, void *ptr ATTRIBUTE_UNUSED) 178{ 179 bfd_set_section_flags (abfd, sec, 180 bfd_get_section_flags (abfd, sec) & ~SEC_RELOC); 181} 182 183/* Iterate with bfd_map_over_sections over mmo_wipe_sec_reloc_flag... */ 184 185static void 186gld${EMULATION_NAME}_after_allocation (void) 187{ 188 bfd_map_over_sections (link_info.output_bfd, mmo_wipe_sec_reloc_flag, NULL); 189 gld${EMULATION_NAME}_map_segments (FALSE); 190} 191 192/* To get on-demand global register allocation right, we need to parse the 193 relocs, like what happens when linking to ELF. It needs to be done 194 before all input sections are supposed to be present. When linking to 195 ELF, it's done when reading symbols. When linking to mmo, we do it 196 when all input files are seen, which is equivalent. */ 197 198static void 199mmo_after_open (void) 200{ 201 /* When there's a mismatch between the output format and the emulation 202 (using weird combinations like "-m mmo --oformat elf64-mmix" for 203 example), we'd count relocs twice because they'd also be counted 204 along the usual route for ELF-only linking, which would lead to an 205 internal accounting error. */ 206 if (bfd_get_flavour (link_info.output_bfd) != bfd_target_elf_flavour) 207 { 208 LANG_FOR_EACH_INPUT_STATEMENT (is) 209 { 210 if (bfd_get_flavour (is->the_bfd) == bfd_target_elf_flavour 211 && !_bfd_mmix_check_all_relocs (is->the_bfd, &link_info)) 212 einfo ("%X%P: Internal problems scanning %B after opening it", 213 is->the_bfd); 214 } 215 } 216 after_open_default (); 217} 218EOF 219 220LDEMUL_PLACE_ORPHAN=mmo_place_orphan 221LDEMUL_AFTER_OPEN=mmo_after_open 222