gcc/config/darwin-sections.def

   1 /* Copyright (C) 2005-2024 Free Software Foundation, Inc.
   2
   3 This file is part of GCC.
   4
   5 GCC is free software; you can redistribute it and/or modify it under
   6 the terms of the GNU General Public License as published by the Free
   7 Software Foundation; either version 3, or (at your option) any later
   8 version.
   9
  10 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  11 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13 for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with GCC; see the file COPYING3.  If not see
  17 <http://www.gnu.org/licenses/>.  */
  18
  19 /* Since Darwin's ld will not allow zero-sized objects, and gcc wants them,
  20    we emit one byte (in darwin.cc) when such an object is encountered.
  21
  22    This messes up section anchoring because the emitted byte is not counted
  23    outside the port.  To cope with this, we set aside sections for zero-sized
  24    objects and disallow those sections from  participating in section anchors
  25    ("zobj_" sections, below).
  26
  27    Items that might be coalesced by the linker are prevented from participating,
  28    (and those in mergeable sections are disallowed in varasm.cc).  */
  29
  30 /* The .text section is generated in varasm.cc  */
  31 DEF_SECTION (text_coal_section, SECTION_CODE|SECTION_NO_ANCHOR,
  32              ".section __TEXT,__textcoal_nt,coalesced,pure_instructions", 0)
  33
  34 /* We define a picbase thunks section separately, so that we can override the
  35    def to be '.text' for versions of ld64 that handle coalescing.  */
  36 DEF_SECTION (picbase_thunk_section, SECTION_CODE|SECTION_NO_ANCHOR,
  37              ".section __TEXT,__textcoal_nt,coalesced,pure_instructions", 0)
  38
  39 DEF_SECTION (text_hot_section, SECTION_CODE,
  40              ".section __TEXT,__text_hot,regular,pure_instructions", 0)
  41 DEF_SECTION (text_cold_section, SECTION_CODE,
  42              ".section __TEXT,__text_cold,regular,pure_instructions", 0)
  43 DEF_SECTION (text_startup_section, SECTION_CODE,
  44              ".section __TEXT,__text_startup,regular,pure_instructions", 0)
  45 DEF_SECTION (text_exit_section, SECTION_CODE,
  46              ".section __TEXT,__text_exit,regular,pure_instructions", 0)
  47
  48 DEF_SECTION (text_hot_coal_section, SECTION_CODE,
  49              ".section __TEXT,__text_hot_coal,coalesced,pure_instructions", 0)
  50 DEF_SECTION (text_cold_coal_section, SECTION_CODE,
  51              ".section __TEXT,__text_cold_coal,coalesced,pure_instructions", 0)
  52 DEF_SECTION (text_startup_coal_section, SECTION_CODE,
  53              ".section __TEXT,__text_stt_coal,coalesced,pure_instructions", 0)
  54 DEF_SECTION (text_exit_coal_section, SECTION_CODE,
  55              ".section __TEXT,__text_exit_coal,coalesced,pure_instructions", 0)
  56
  57 /* const */
  58 DEF_SECTION (const_section, 0, ".const", 0)
  59 DEF_SECTION (const_coal_section, SECTION_NO_ANCHOR,
  60              ".section __TEXT,__const_coal,coalesced", 0)
  61 /* Place to put zero-sized to avoid issues with section anchors.  */
  62 DEF_SECTION (zobj_const_section, SECTION_NO_ANCHOR,
  63              ".section\t__DATA,__zobj_const", 0)
  64
  65 /* Write-able data.  '.data'  handled in varasm.cc  */
  66 DEF_SECTION (static_data_section, SECTION_WRITE, ".static_data", 0)
  67 DEF_SECTION (data_coal_section, SECTION_WRITE|SECTION_NO_ANCHOR,
  68              ".section __DATA,__datacoal_nt,coalesced", 0)
  69 /* Place to put zero-sized to avoid issues with section anchors.  */
  70 DEF_SECTION (zobj_data_section, SECTION_WRITE|SECTION_NO_ANCHOR,
  71              ".section\t__DATA,__zobj_data", 0)
  72
  73 /* BSS - .lcomm / .zerofill __DATA,__bss sections cannot be switched to
  74    explicitly (will create an assembler error).  */
  75 DEF_SECTION (zobj_bss_section, SECTION_WRITE|SECTION_BSS|SECTION_NO_ANCHOR,
  76              ".section\t__DATA,__zobj_bss", 0)
  77
  78 /* const data */
  79 DEF_SECTION (const_data_section, 0, ".const_data", 0)
  80 DEF_SECTION (const_data_coal_section, SECTION_NO_ANCHOR,
  81              ".section __DATA,__const_coal,coalesced", 0)
  82 /* Place to put zero-sized to avoid issues with section anchors.  */
  83 DEF_SECTION (zobj_const_data_section, SECTION_NO_ANCHOR,
  84              ".section\t__DATA,__zobj_cnst_data", 0)
  85
  86 /* Strings and other literals.  */
  87 DEF_SECTION (cstring_section, SECTION_MERGE | SECTION_STRINGS, ".cstring", 0)
  88 DEF_SECTION (literal4_section, SECTION_MERGE, ".literal4", 0)
  89 DEF_SECTION (literal8_section, SECTION_MERGE, ".literal8", 0)
  90 DEF_SECTION (literal16_section, SECTION_MERGE, ".literal16", 0)
  91 /* Unlike constant NSStrings, constant CFStrings do not live  in the
  92    __OBJC segment since they may also occur in pure C  or C++ programs.  */
  93 DEF_SECTION (cfstring_constant_object_section, 0,
  94              ".section __DATA, __cfstring", 0)
  95
  96 /* Module init, term, constructors & destructors.  */
  97 DEF_SECTION (mod_init_section, 0, ".mod_init_func", 0)
  98 DEF_SECTION (mod_term_section, 0, ".mod_term_func", 0)
  99 DEF_SECTION (constructor_section, 0, ".constructor", 0)
 100 DEF_SECTION (destructor_section, 0, ".destructor", 0)
 101 DEF_SECTION (static_init_section, SECTION_CODE,
 102              ".section\t__TEXT,__StaticInit,regular,pure_instructions", 0)
 103
 104 /* Objective-C ABI=0 (Original version) sections.  */
 105 DEF_SECTION (objc_class_section, 0, ".objc_class", 1)
 106 DEF_SECTION (objc_meta_class_section, 0, ".objc_meta_class", 1)
 107 DEF_SECTION (objc_category_section, 0, ".objc_category", 1)
 108 DEF_SECTION (objc_class_vars_section, 0, ".objc_class_vars", 1)
 109 DEF_SECTION (objc_instance_vars_section, 0, ".objc_instance_vars", 1)
 110 DEF_SECTION (objc_cls_meth_section, 0, ".objc_cls_meth", 1)
 111 DEF_SECTION (objc_inst_meth_section, 0, ".objc_inst_meth", 1)
 112 DEF_SECTION (objc_cat_cls_meth_section, 0, ".objc_cat_cls_meth", 1)
 113 DEF_SECTION (objc_cat_inst_meth_section, 0, ".objc_cat_inst_meth", 1)
 114 DEF_SECTION (objc_selector_refs_section, SECTION_MERGE, ".objc_message_refs", 1)
 115 DEF_SECTION (objc_selector_fixup_section, 0,
 116             ".section __OBJC, __sel_fixup, regular, no_dead_strip", 1)
 117 DEF_SECTION (objc_symbols_section, 0, ".objc_symbols", 1)
 118 DEF_SECTION (objc_module_info_section, 0, ".objc_module_info", 1)
 119 DEF_SECTION (objc_protocol_section, 0, ".objc_protocol", 1)
 120 DEF_SECTION (objc_string_object_section, 0, ".objc_string_object", 1)
 121 DEF_SECTION (objc_constant_string_object_section, 0,
 122              ".section __OBJC, __cstring_object, regular, no_dead_strip", 0)
 123
 124 /* Fix-and-Continue image marker.  */
 125 DEF_SECTION (objc_image_info_section, 0,
 126              ".section __OBJC, __image_info, regular, no_dead_strip", 1)
 127 DEF_SECTION (objc_class_names_section, 0, ".objc_class_names", 1)
 128 DEF_SECTION (objc_meth_var_names_section, 0, ".objc_meth_var_names", 1)
 129 DEF_SECTION (objc_meth_var_types_section, 0, ".objc_meth_var_types", 1)
 130 DEF_SECTION (objc_cls_refs_section, SECTION_MERGE, ".objc_cls_refs", 1)
 131
 132 /* Stubs and symbol indirection sections.  */
 133 /* lazy symbol pointers.  */
 134 DEF_SECTION (machopic_lazy_symbol_ptr_section, SECTION_NO_ANCHOR,
 135              ".lazy_symbol_pointer", 0)
 136 DEF_SECTION (machopic_lazy_symbol_ptr2_section, SECTION_NO_ANCHOR,
 137              ".section __DATA, __la_sym_ptr2,lazy_symbol_pointers", 0)
 138 DEF_SECTION (machopic_lazy_symbol_ptr3_section, SECTION_NO_ANCHOR,
 139              ".section __DATA, __la_sym_ptr3,lazy_symbol_pointers", 0)
 140 /* non-lazy symbol pointers.  */
 141 DEF_SECTION (machopic_nl_symbol_ptr_section, SECTION_NO_ANCHOR,
 142              MACHOPIC_NL_SYMBOL_PTR_SECTION, 0)
 143 /* Symbol stubs.  */
 144 DEF_SECTION (machopic_symbol_stub_section, SECTION_NO_ANCHOR,
 145              ".symbol_stub", 0)
 146 DEF_SECTION (machopic_symbol_stub1_section, SECTION_NO_ANCHOR,
 147              ".section __TEXT,__symbol_stub1,symbol_stubs,"
 148              "pure_instructions,16", 0)
 149 /* PIC symbol stubs.  */
 150 DEF_SECTION (machopic_picsymbol_stub_section, SECTION_NO_ANCHOR,
 151              ".picsymbol_stub", 0)
 152 DEF_SECTION (machopic_picsymbol_stub1_section, SECTION_NO_ANCHOR,
 153              ".section __TEXT,__picsymbolstub1,symbol_stubs,"
 154              "pure_instructions,32", 0)
 155 DEF_SECTION (machopic_picsymbol_stub2_section, SECTION_NO_ANCHOR,
 156              ".section __TEXT,__picsymbolstub2,symbol_stubs,pure_instructions,25", 0)
 157 DEF_SECTION (machopic_picsymbol_stub3_section, SECTION_NO_ANCHOR,
 158              ".section __IMPORT,__jump_table,symbol_stubs,self_modifying_code+pure_instructions,5", 0)
 159
 160 /* Exception-related.  */
 161 DEF_SECTION (darwin_exception_section, SECTION_NO_ANCHOR,
 162              ".section __TEXT,__gcc_except_tab", 0)
 163 DEF_SECTION (darwin_eh_frame_section, SECTION_NO_ANCHOR,
 164              ".section " EH_FRAME_SECTION_NAME ",__eh_frame"
 165              EH_FRAME_SECTION_ATTR, 0)
 166
 167 /* Sections for ObjC ABI=1 (ObjC 'V1' extensions) */
 168 DEF_SECTION (objc1_class_ext_section, 0,
 169             ".section __OBJC, __class_ext, regular, no_dead_strip", 1)
 170 DEF_SECTION (objc1_prop_list_section, 0,
 171             ".section __OBJC, __property, regular, no_dead_strip", 1)
 172 DEF_SECTION (objc1_protocol_ext_section, 0,
 173             ".section __OBJC, __protocol_ext, regular, no_dead_strip", 1)
 174
 175 /* Sections for ObjC ABI=2 (m64).  */
 176 DEF_SECTION (objc2_message_refs_section, 0,
 177              ".section __DATA, __objc_msgrefs, regular, no_dead_strip", 1)
 178 DEF_SECTION (objc2_classdefs_section, 0, ".section __DATA, __objc_data", 1)
 179 DEF_SECTION (objc2_metadata_section, 0, ".section __DATA, __objc_const", 1)
 180
 181 DEF_SECTION (objc2_classrefs_section, 0,
 182              ".section __DATA, __objc_classrefs, regular, no_dead_strip", 1)
 183 DEF_SECTION (objc2_classlist_section, 0,
 184              ".section __DATA, __objc_classlist, regular, no_dead_strip", 1)
 185 DEF_SECTION (objc2_categorylist_section, 0,
 186              ".section __DATA, __objc_catlist, regular, no_dead_strip", 1)
 187 DEF_SECTION (objc2_selector_refs_section, 0,
 188              ".section __DATA, __objc_selrefs, literal_pointers, no_dead_strip", 1)
 189 DEF_SECTION (objc2_nonlazy_class_section, 0,
 190              ".section __DATA, __objc_nlclslist, regular, no_dead_strip", 1)
 191 DEF_SECTION (objc2_nonlazy_category_section, 0,
 192              ".section __DATA, __objc_nlcatlist, regular, no_dead_strip", 1)
 193 DEF_SECTION (objc2_protocollist_section, 0,
 194              ".section __DATA, __objc_protolist, regular, no_dead_strip", 1)
 195 DEF_SECTION (objc2_protocolrefs_section, 0,
 196              ".section __DATA, __objc_protorefs, regular, no_dead_strip", 1)
 197 DEF_SECTION (objc2_super_classrefs_section, 0,
 198              ".section __DATA, __objc_superrefs, regular, no_dead_strip", 1)
 199 DEF_SECTION (objc2_image_info_section, 0,
 200              ".section __DATA, __objc_imageinfo, regular, no_dead_strip", 1)
 201 DEF_SECTION (objc2_constant_string_object_section, 0,
 202              ".section __DATA, __objc_stringobj, regular, no_dead_strip", 1)
 203
 204 /* Additions for compatibility with later runtime conventions especially for
 205    sections containing strings.  */
 206 DEF_SECTION (objc2_data_section, 0, ".section __DATA, __data", 1)
 207
 208 DEF_SECTION (objc2_ivar_section, 0, ".section __DATA, __objc_ivar", 1)
 209
 210 DEF_SECTION (objc2_class_names_section, 0,
 211              ".section __TEXT, __objc_classname, cstring_literals", 1)
 212
 213 DEF_SECTION (objc2_method_names_section, 0,
 214              ".section __TEXT, __objc_methname, cstring_literals", 1)
 215
 216 DEF_SECTION (objc2_method_types_section, 0,
 217              ".section __TEXT, __objc_methtype, cstring_literals", 1)