1 # This shell script emits a C file. -*- C -*- 2 # Copyright (C) 2001-2014 Free Software Foundation, Inc. 3 # 4 # This file is part of the GNU Binutils. 5 # 6 # This program is free software; you can redistribute it and/or modify 7 # it under the terms of the GNU General Public License as published by 8 # the Free Software Foundation; either version 3 of the License, or 9 # (at your option) any later version. 10 # 11 # This program is distributed in the hope that it will be useful, 12 # but WITHOUT ANY WARRANTY; without even the implied warranty of 13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 # GNU General Public License for more details. 15 # 16 # You should have received a copy of the GNU General Public License 17 # along with this program; if not, write to the Free Software 18 # Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 19 # MA 02110-1301, USA. 20 # 21 22 # This file is sourced from generic.em. 23 24 fragment <<EOF 25 /* Need to have this macro defined before mmix-elfnmmo, which uses the 26 name for the before_allocation function, defined in ldemul.c (for 27 the mmo "emulation") or in elf32.em (for the elf64mmix 28 "emulation"). */ 29 #define gldmmo_before_allocation before_allocation_default 30 31 /* We include this header *not* because we expect to handle ELF here 32 but because we re-use the map_segments function in elf-generic.em, 33 a file which is rightly somewhat ELF-centric. But this is only to 34 get a weird testcase right; ld-mmix/bpo-22, forcing ELF to be 35 output from the mmo emulation: -m mmo --oformat elf64-mmix! */ 36 #include "elf-bfd.h" 37 38 static void gld${EMULATION_NAME}_after_allocation (void); 39 EOF 40 41 source_em ${srcdir}/emultempl/elf-generic.em 42 source_em ${srcdir}/emultempl/mmix-elfnmmo.em 43 44 fragment <<EOF 45 46 /* Place an orphan section. We use this to put random SEC_CODE or 47 SEC_READONLY sections right after MMO_TEXT_SECTION_NAME. Much borrowed 48 from elf32.em. */ 49 50 static lang_output_section_statement_type * 51 mmo_place_orphan (asection *s, 52 const char *secname, 53 int constraint ATTRIBUTE_UNUSED) 54 { 55 static struct 56 { 57 flagword nonzero_flags; 58 struct orphan_save orphansave; 59 } holds[] = 60 { 61 { 62 SEC_CODE | SEC_READONLY, 63 { 64 MMO_TEXT_SECTION_NAME, 65 SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE, 66 0, 0, 0, 0 67 } 68 }, 69 { 70 SEC_LOAD | SEC_DATA, 71 { 72 MMO_DATA_SECTION_NAME, 73 SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_DATA, 74 0, 0, 0, 0 75 } 76 }, 77 { 78 SEC_ALLOC, 79 { 80 ".bss", 81 SEC_ALLOC, 82 0, 0, 0, 0 83 } 84 } 85 }; 86 87 struct orphan_save *place = NULL; 88 lang_output_section_statement_type *after; 89 lang_output_section_statement_type *os; 90 size_t i; 91 92 /* We have nothing to say for anything other than a final link or 93 for sections that are excluded. */ 94 if (link_info.relocatable 95 || (s->flags & SEC_EXCLUDE) != 0) 96 return NULL; 97 98 os = lang_output_section_find (secname); 99 100 /* We have an output section by this name. Place the section inside it 101 (regardless of whether the linker script lists it as input). */ 102 if (os != NULL) 103 { 104 lang_add_section (&os->children, s, NULL, os); 105 return os; 106 } 107 108 /* Check for matching section type flags for sections we care about. 109 A section without contents can have SEC_LOAD == 0, but we still 110 want it attached to a sane section so the symbols appear as 111 expected. */ 112 if ((s->flags & (SEC_ALLOC | SEC_READONLY)) != SEC_READONLY) 113 for (i = 0; i < sizeof (holds) / sizeof (holds[0]); i++) 114 if ((s->flags & holds[i].nonzero_flags) != 0) 115 { 116 place = &holds[i].orphansave; 117 if (place->os == NULL) 118 place->os = lang_output_section_find (place->name); 119 break; 120 } 121 122 if (place == NULL) 123 { 124 /* For other combinations, we have to give up, except we make 125 sure not to place the orphan section after the 126 linker-generated register section; that'd make it continue 127 the reg section and we never want that to happen for orphan 128 sections. */ 129 lang_output_section_statement_type *before; 130 lang_output_section_statement_type *lookup; 131 static struct orphan_save hold_nonreg = 132 { 133 NULL, 134 SEC_READONLY, 135 0, 0, 0, 0 136 }; 137 138 if (hold_nonreg.os == NULL) 139 { 140 before = lang_output_section_find (MMIX_REG_CONTENTS_SECTION_NAME); 141 142 /* If we have no such section, all fine; we don't care where 143 it's placed. */ 144 if (before == NULL) 145 return NULL; 146 147 /* We have to find the oss before this one, so we can use that as 148 "after". */ 149 for (lookup = &lang_output_section_statement.head->output_section_statement; 150 lookup != NULL && lookup->next != before; 151 lookup = lookup->next) 152 ; 153 154 hold_nonreg.os = lookup; 155 } 156 157 place = &hold_nonreg; 158 } 159 160 after = place->os; 161 if (after == NULL) 162 return NULL; 163 164 /* If there's an output section by *this* name, we'll use it, regardless 165 of actual section flags, in contrast to what's done in elf32.em. */ 166 os = lang_insert_orphan (s, secname, 0, after, place, NULL, NULL); 167 168 return os; 169 } 170 171 /* Remove the spurious settings of SEC_RELOC that make it to the output at 172 link time. We are as confused as elflink.h:elf_bfd_final_link, and 173 paper over the bug similarly. */ 174 175 static void 176 mmo_wipe_sec_reloc_flag (bfd *abfd, asection *sec, void *ptr ATTRIBUTE_UNUSED) 177 { 178 bfd_set_section_flags (abfd, sec, 179 bfd_get_section_flags (abfd, sec) & ~SEC_RELOC); 180 } 181 182 /* Iterate with bfd_map_over_sections over mmo_wipe_sec_reloc_flag... */ 183 184 static void 185 gld${EMULATION_NAME}_after_allocation (void) 186 { 187 bfd_map_over_sections (link_info.output_bfd, mmo_wipe_sec_reloc_flag, NULL); 188 gld${EMULATION_NAME}_map_segments (FALSE); 189 } 190 192 /* 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. */ 197 198 static void 199 mmo_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 } 218 EOF 219 220 LDEMUL_PLACE_ORPHAN=mmo_place_orphan 221 LDEMUL_AFTER_OPEN=mmo_after_open 222
