diff options
Diffstat (limited to 'binutils-2.25/gas/config/obj-macho.c')
| -rw-r--r-- | binutils-2.25/gas/config/obj-macho.c | 1990 |
1 files changed, 1990 insertions, 0 deletions
diff --git a/binutils-2.25/gas/config/obj-macho.c b/binutils-2.25/gas/config/obj-macho.c new file mode 100644 index 00000000..21281a0e --- /dev/null +++ b/binutils-2.25/gas/config/obj-macho.c @@ -0,0 +1,1990 @@ +/* Mach-O object file format + Copyright 2009, 2011, 2012 Free Software Foundation, Inc. + + This file is part of GAS, the GNU Assembler. + + GAS 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, + or (at your option) any later version. + + GAS 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 GAS; see the file COPYING. If not, write to the Free + Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA + 02110-1301, USA. */ + +/* Here we handle the mach-o directives that are common to all architectures. + + Most significant are mach-o named sections and a variety of symbol type + decorations. */ + +/* Mach-O supports multiple, named segments each of which may contain + multiple named sections. Thus the concept of subsectioning is + handled by (say) having a __TEXT segment with appropriate flags from + which subsections are generated like __text, __const etc. + + The well-known as short-hand section switch directives like .text, .data + etc. are mapped onto predefined segment/section pairs using facilites + supplied by the mach-o port of bfd. + + A number of additional mach-o short-hand section switch directives are + also defined. */ + +#define OBJ_HEADER "obj-macho.h" + +#include "as.h" +#include "subsegs.h" +#include "symbols.h" +#include "write.h" +#include "mach-o.h" +#include "mach-o/loader.h" +#include "obj-macho.h" + +#include <string.h> + +/* Forward decls. */ +static segT obj_mach_o_segT_from_bfd_name (const char *, int); + +/* TODO: Implement "-dynamic"/"-static" command line options. */ + +static int obj_mach_o_is_static; + +/* TODO: Implement the "-n" command line option to suppress the initial + switch to the text segment. */ + +static int obj_mach_o_start_with_text_section = 1; + +/* Allow for special re-ordering on output. */ + +static int obj_mach_o_seen_objc_section; + +/* Start-up: At present, just create the sections we want. */ +void +mach_o_begin (void) +{ + /* Mach-O only defines the .text section by default, and even this can + be suppressed by a flag. In the latter event, the first code MUST + be a section definition. */ + if (obj_mach_o_start_with_text_section) + { + text_section = obj_mach_o_segT_from_bfd_name (TEXT_SECTION_NAME, 1); + subseg_set (text_section, 0); + if (obj_mach_o_is_static) + { + bfd_mach_o_section *mo_sec + = bfd_mach_o_get_mach_o_section (text_section); + mo_sec->flags &= ~BFD_MACH_O_S_ATTR_PURE_INSTRUCTIONS; + } + } +} + +/* Remember the subsections_by_symbols state in case we need to reset + the file flags. */ + +static int obj_mach_o_subsections_by_symbols; + +/* This will put at most 16 characters (terminated by a ',' or newline) from + the input stream into dest. If there are more than 16 chars before the + delimiter, a warning is given and the string is truncated. On completion of + this function, input_line_pointer will point to the char after the ',' or + to the newline. + + It trims leading and trailing space. */ + +static int +collect_16char_name (char *dest, const char *msg, int require_comma) +{ + char c, *namstart; + + SKIP_WHITESPACE (); + namstart = input_line_pointer; + + while ( (c = *input_line_pointer) != ',' + && !is_end_of_line[(unsigned char) c]) + input_line_pointer++; + + { + int len = input_line_pointer - namstart; /* could be zero. */ + /* lose any trailing space. */ + while (len > 0 && namstart[len-1] == ' ') + len--; + if (len > 16) + { + *input_line_pointer = '\0'; /* make a temp string. */ + as_bad (_("the %s name '%s' is too long (maximum 16 characters)"), + msg, namstart); + *input_line_pointer = c; /* restore for printing. */ + len = 16; + } + if (len > 0) + memcpy (dest, namstart, len); + } + + if (c != ',' && require_comma) + { + as_bad (_("expected a %s name followed by a `,'"), msg); + return 1; + } + + return 0; +} + +static int +obj_mach_o_get_section_names (char *seg, char *sec, + unsigned segl, unsigned secl) +{ + /* Zero-length segment and section names are allowed. */ + /* Parse segment name. */ + memset (seg, 0, segl); + if (collect_16char_name (seg, "segment", 1)) + { + ignore_rest_of_line (); + return 0; + } + input_line_pointer++; /* Skip the terminating ',' */ + + /* Parse section name, which can be empty. */ + memset (sec, 0, secl); + collect_16char_name (sec, "section", 0); + return 1; +} + +/* Build (or get) a section from the mach-o description - which includes + optional definitions for type, attributes, alignment and stub size. + + BFD supplies default values for sections which have a canonical name. */ + +#define SECT_TYPE_SPECIFIED 0x0001 +#define SECT_ATTR_SPECIFIED 0x0002 +#define SECT_ALGN_SPECIFIED 0x0004 +#define SECT_STUB_SPECIFIED 0x0008 + +static segT +obj_mach_o_make_or_get_sect (char * segname, char * sectname, + unsigned int specified_mask, + unsigned int usectype, unsigned int usecattr, + unsigned int ualign, offsetT stub_size) +{ + unsigned int sectype, secattr, secalign; + flagword oldflags, flags; + const char *name; + segT sec; + bfd_mach_o_section *msect; + const mach_o_section_name_xlat *xlat; + + /* This provides default bfd flags and default mach-o section type and + attributes along with the canonical name. */ + xlat = bfd_mach_o_section_data_for_mach_sect (stdoutput, segname, sectname); + + /* TODO: more checking of whether overides are acually allowed. */ + + if (xlat != NULL) + { + name = xstrdup (xlat->bfd_name); + sectype = xlat->macho_sectype; + if (specified_mask & SECT_TYPE_SPECIFIED) + { + if ((sectype == BFD_MACH_O_S_ZEROFILL + || sectype == BFD_MACH_O_S_GB_ZEROFILL) + && sectype != usectype) + as_bad (_("cannot overide zerofill section type for `%s,%s'"), + segname, sectname); + else + sectype = usectype; + } + secattr = xlat->macho_secattr; + secalign = xlat->sectalign; + flags = xlat->bfd_flags; + } + else + { + /* There is no normal BFD section name for this section. Create one. + The name created doesn't really matter as it will never be written + on disk. */ + size_t seglen = strlen (segname); + size_t sectlen = strlen (sectname); + char *n; + + n = xmalloc (seglen + 1 + sectlen + 1); + memcpy (n, segname, seglen); + n[seglen] = '.'; + memcpy (n + seglen + 1, sectname, sectlen); + n[seglen + 1 + sectlen] = 0; + name = n; + if (specified_mask & SECT_TYPE_SPECIFIED) + sectype = usectype; + else + sectype = BFD_MACH_O_S_REGULAR; + secattr = BFD_MACH_O_S_ATTR_NONE; + secalign = 0; + flags = SEC_NO_FLAGS; + } + + /* For now, just use what the user provided. */ + + if (specified_mask & SECT_ATTR_SPECIFIED) + secattr = usecattr; + + if (specified_mask & SECT_ALGN_SPECIFIED) + secalign = ualign; + + /* Sub-segments don't exists as is on Mach-O. */ + sec = subseg_new (name, 0); + + oldflags = bfd_get_section_flags (stdoutput, sec); + msect = bfd_mach_o_get_mach_o_section (sec); + + if (oldflags == SEC_NO_FLAGS) + { + /* In the absence of canonical information, try to determine CODE and + DEBUG section flags from the mach-o section data. */ + if (flags == SEC_NO_FLAGS + && (specified_mask & SECT_ATTR_SPECIFIED) + && (secattr & BFD_MACH_O_S_ATTR_PURE_INSTRUCTIONS)) + flags |= SEC_CODE; + + if (flags == SEC_NO_FLAGS + && (specified_mask & SECT_ATTR_SPECIFIED) + && (secattr & BFD_MACH_O_S_ATTR_DEBUG)) + flags |= SEC_DEBUGGING; + + /* New, so just use the defaults or what's specified. */ + if (! bfd_set_section_flags (stdoutput, sec, flags)) + as_warn (_("failed to set flags for \"%s\": %s"), + bfd_section_name (stdoutput, sec), + bfd_errmsg (bfd_get_error ())); + + strncpy (msect->segname, segname, sizeof (msect->segname)); + strncpy (msect->sectname, sectname, sizeof (msect->sectname)); + + msect->align = secalign; + msect->flags = sectype | secattr; + + if (sectype == BFD_MACH_O_S_ZEROFILL + || sectype == BFD_MACH_O_S_GB_ZEROFILL) + seg_info (sec)->bss = 1; + } + else if (flags != SEC_NO_FLAGS) + { + if (flags != oldflags + || msect->flags != (secattr | sectype)) + as_warn (_("Ignoring changed section attributes for %s"), name); + } + + if (specified_mask & SECT_STUB_SPECIFIED) + /* At present, the stub size is not supplied from the BFD tables. */ + msect->reserved2 = stub_size; + + return sec; +} + +/* .section + + The '.section' specification syntax looks like: + .section <segment> , <section> [, type [, attribs [, size]]] + + White space is allowed everywhere between elements. + + <segment> and <section> may be from 0 to 16 chars in length - they may + contain spaces but leading and trailing space will be trimmed. It is + mandatory that they be present (or that zero-length names are indicated + by ",,"). + + There is only a single section type for any entry. + + There may be multiple attributes, they are delimited by `+'. + + Not all section types and attributes are accepted by the Darwin system + assemblers as user-specifiable - although, at present, we do here. */ + +static void +obj_mach_o_section (int ignore ATTRIBUTE_UNUSED) +{ + unsigned int sectype = BFD_MACH_O_S_REGULAR; + unsigned int specified_mask = 0; + unsigned int secattr = 0; + offsetT sizeof_stub = 0; + segT new_seg; + char segname[17]; + char sectname[17]; + +#ifdef md_flush_pending_output + md_flush_pending_output (); +#endif + + /* Get the User's segment annd section names. */ + if (! obj_mach_o_get_section_names (segname, sectname, 17, 17)) + return; + + /* Parse section type, if present. */ + if (*input_line_pointer == ',') + { + char *p; + char c; + char tmpc; + int len; + input_line_pointer++; + SKIP_WHITESPACE (); + p = input_line_pointer; + while ((c = *input_line_pointer) != ',' + && !is_end_of_line[(unsigned char) c]) + input_line_pointer++; + + len = input_line_pointer - p; + /* strip trailing spaces. */ + while (len > 0 && p[len-1] == ' ') + len--; + tmpc = p[len]; + + /* Temporarily make a string from the token. */ + p[len] = 0; + sectype = bfd_mach_o_get_section_type_from_name (stdoutput, p); + if (sectype > 255) /* Max Section ID == 255. */ + { + as_bad (_("unknown or invalid section type '%s'"), p); + p[len] = tmpc; + ignore_rest_of_line (); + return; + } + else + specified_mask |= SECT_TYPE_SPECIFIED; + /* Restore. */ + p[len] = tmpc; + + /* Parse attributes. + TODO: check validity of attributes for section type. */ + if ((specified_mask & SECT_TYPE_SPECIFIED) + && c == ',') + { + do + { + int attr; + + /* Skip initial `,' and subsequent `+'. */ + input_line_pointer++; + SKIP_WHITESPACE (); + p = input_line_pointer; + while ((c = *input_line_pointer) != '+' + && c != ',' + && !is_end_of_line[(unsigned char) c]) + input_line_pointer++; + + len = input_line_pointer - p; + /* strip trailing spaces. */ + while (len > 0 && p[len-1] == ' ') + len--; + tmpc = p[len]; + + /* Temporarily make a string from the token. */ + p[len] ='\0'; + attr = bfd_mach_o_get_section_attribute_from_name (p); + if (attr == -1) + { + as_bad (_("unknown or invalid section attribute '%s'"), p); + p[len] = tmpc; + ignore_rest_of_line (); + return; + } + else + { + specified_mask |= SECT_ATTR_SPECIFIED; + secattr |= attr; + } + /* Restore. */ + p[len] = tmpc; + } + while (*input_line_pointer == '+'); + + /* Parse sizeof_stub. */ + if ((specified_mask & SECT_ATTR_SPECIFIED) + && *input_line_pointer == ',') + { + if (sectype != BFD_MACH_O_S_SYMBOL_STUBS) + { + as_bad (_("unexpected section size information")); + ignore_rest_of_line (); + return; + } + + input_line_pointer++; + sizeof_stub = get_absolute_expression (); + specified_mask |= SECT_STUB_SPECIFIED; + } + else if ((specified_mask & SECT_ATTR_SPECIFIED) + && sectype == BFD_MACH_O_S_SYMBOL_STUBS) + { + as_bad (_("missing sizeof_stub expression")); + ignore_rest_of_line (); + return; + } + } + } + + new_seg = obj_mach_o_make_or_get_sect (segname, sectname, specified_mask, + sectype, secattr, 0 /*align */, + sizeof_stub); + if (new_seg != NULL) + { + subseg_set (new_seg, 0); + demand_empty_rest_of_line (); + } +} + +/* .zerofill segname, sectname [, symbolname, size [, align]] + + Zerofill switches, temporarily, to a sect of type 'zerofill'. + + If a variable name is given, it defines that in the section. + Otherwise it just creates the section if it doesn't exist. */ + +static void +obj_mach_o_zerofill (int ignore ATTRIBUTE_UNUSED) +{ + char segname[17]; + char sectname[17]; + segT old_seg = now_seg; + segT new_seg; + symbolS *sym = NULL; + unsigned int align = 0; + unsigned int specified_mask = 0; + offsetT size = 0; + +#ifdef md_flush_pending_output + md_flush_pending_output (); +#endif + + /* Get the User's segment annd section names. */ + if (! obj_mach_o_get_section_names (segname, sectname, 17, 17)) + return; + + /* Parse variable definition, if present. */ + if (*input_line_pointer == ',') + { + /* Parse symbol, size [.align] + We follow the method of s_common_internal, with the difference + that the symbol cannot be a duplicate-common. */ + char *name; + char c; + char *p; + expressionS exp; + + input_line_pointer++; /* Skip ',' */ + SKIP_WHITESPACE (); + name = input_line_pointer; + c = get_symbol_end (); + /* Just after name is now '\0'. */ + p = input_line_pointer; + *p = c; + + if (name == p) + { + as_bad (_("expected symbol name")); + ignore_rest_of_line (); + goto done; + } + + SKIP_WHITESPACE (); + if (*input_line_pointer == ',') + input_line_pointer++; + + expression_and_evaluate (&exp); + if (exp.X_op != O_constant + && exp.X_op != O_absent) + { + as_bad (_("bad or irreducible absolute expression")); + ignore_rest_of_line (); + goto done; + } + else if (exp.X_op == O_absent) + { + as_bad (_("missing size expression")); + ignore_rest_of_line (); + goto done; + } + + size = exp.X_add_number; + size &= ((offsetT) 2 << (stdoutput->arch_info->bits_per_address - 1)) - 1; + if (exp.X_add_number != size || !exp.X_unsigned) + { + as_warn (_("size (%ld) out of range, ignored"), + (long) exp.X_add_number); + ignore_rest_of_line (); + goto done; + } + + *p = 0; /* Make the name into a c string for err messages. */ + sym = symbol_find_or_make (name); + if (S_IS_DEFINED (sym) || symbol_equated_p (sym)) + { + as_bad (_("symbol `%s' is already defined"), name); + *p = c; + ignore_rest_of_line (); + goto done; + } + + size = S_GET_VALUE (sym); + if (size == 0) + size = exp.X_add_number; + else if (size != exp.X_add_number) + as_warn (_("size of \"%s\" is already %ld; not changing to %ld"), + name, (long) size, (long) exp.X_add_number); + + *p = c; /* Restore the termination char. */ + + SKIP_WHITESPACE (); + if (*input_line_pointer == ',') + { + align = (unsigned int) parse_align (0); + if (align == (unsigned int) -1) + { + as_warn (_("align value not recognized, using size")); + align = size; + } + if (align > 15) + { + as_warn (_("Alignment (%lu) too large: 15 assumed."), + (unsigned long)align); + align = 15; + } + specified_mask |= SECT_ALGN_SPECIFIED; + } + } + /* else just a section definition. */ + + specified_mask |= SECT_TYPE_SPECIFIED; + new_seg = obj_mach_o_make_or_get_sect (segname, sectname, specified_mask, + BFD_MACH_O_S_ZEROFILL, + BFD_MACH_O_S_ATTR_NONE, + align, (offsetT) 0 /*stub size*/); + if (new_seg == NULL) + return; + + /* In case the user specifies the bss section by mach-o name. + Create it on demand */ + if (strcmp (new_seg->name, BSS_SECTION_NAME) == 0 + && bss_section == NULL) + bss_section = new_seg; + + subseg_set (new_seg, 0); + + if (sym != NULL) + { + char *pfrag; + + if (align) + { + record_alignment (new_seg, align); + frag_align (align, 0, 0); + } + + /* Detach from old frag. */ + if (S_GET_SEGMENT (sym) == new_seg) + symbol_get_frag (sym)->fr_symbol = NULL; + + symbol_set_frag (sym, frag_now); + pfrag = frag_var (rs_org, 1, 1, 0, sym, size, NULL); + *pfrag = 0; + + S_SET_SEGMENT (sym, new_seg); + if (new_seg == bss_section) + S_CLEAR_EXTERNAL (sym); + } + +done: + /* switch back to the section that was current before the .zerofill. */ + subseg_set (old_seg, 0); +} + +static segT +obj_mach_o_segT_from_bfd_name (const char *nam, int must_succeed) +{ + const mach_o_section_name_xlat *xlat; + const char *segn; + segT sec; + + /* BFD has tables of flags and default attributes for all the sections that + have a 'canonical' name. */ + xlat = bfd_mach_o_section_data_for_bfd_name (stdoutput, nam, &segn); + if (xlat == NULL) + { + if (must_succeed) + as_fatal (_("BFD is out of sync with GAS, " + "unhandled well-known section type `%s'"), nam); + return NULL; + } + + sec = bfd_get_section_by_name (stdoutput, nam); + if (sec == NULL) + { + bfd_mach_o_section *msect; + + sec = subseg_force_new (xlat->bfd_name, 0); + + /* Set default type, attributes and alignment. */ + msect = bfd_mach_o_get_mach_o_section (sec); + msect->flags = xlat->macho_sectype | xlat->macho_secattr; + msect->align = xlat->sectalign; + + if ((msect->flags & BFD_MACH_O_SECTION_TYPE_MASK) + == BFD_MACH_O_S_ZEROFILL) + seg_info (sec)->bss = 1; + } + + return sec; +} + +static const char * const known_sections[] = +{ + /* 0 */ NULL, + /* __TEXT */ + /* 1 */ ".const", + /* 2 */ ".static_const", + /* 3 */ ".cstring", + /* 4 */ ".literal4", + /* 5 */ ".literal8", + /* 6 */ ".literal16", + /* 7 */ ".constructor", + /* 8 */ ".destructor", + /* 9 */ ".eh_frame", + /* __DATA */ + /* 10 */ ".const_data", + /* 11 */ ".static_data", + /* 12 */ ".mod_init_func", + /* 13 */ ".mod_term_func", + /* 14 */ ".dyld", + /* 15 */ ".cfstring" +}; + +/* Interface for a known non-optional section directive. */ + +static void +obj_mach_o_known_section (int sect_index) +{ + segT section; + +#ifdef md_flush_pending_output + md_flush_pending_output (); +#endif + + section = obj_mach_o_segT_from_bfd_name (known_sections[sect_index], 1); + if (section != NULL) + subseg_set (section, 0); + + /* else, we leave the section as it was; there was a fatal error anyway. */ +} + +static const char * const objc_sections[] = +{ + /* 0 */ NULL, + /* 1 */ ".objc_class", + /* 2 */ ".objc_meta_class", + /* 3 */ ".objc_cat_cls_meth", + /* 4 */ ".objc_cat_inst_meth", + /* 5 */ ".objc_protocol", + /* 6 */ ".objc_string_object", + /* 7 */ ".objc_cls_meth", + /* 8 */ ".objc_inst_meth", + /* 9 */ ".objc_cls_refs", + /* 10 */ ".objc_message_refs", + /* 11 */ ".objc_symbols", + /* 12 */ ".objc_category", + /* 13 */ ".objc_class_vars", + /* 14 */ ".objc_instance_vars", + /* 15 */ ".objc_module_info", + /* 16 */ ".cstring", /* objc_class_names Alias for .cstring */ + /* 17 */ ".cstring", /* Alias objc_meth_var_types for .cstring */ + /* 18 */ ".cstring", /* objc_meth_var_names Alias for .cstring */ + /* 19 */ ".objc_selector_strs", + /* 20 */ ".objc_image_info", /* extension. */ + /* 21 */ ".objc_selector_fixup", /* extension. */ + /* 22 */ ".objc1_class_ext", /* ObjC-1 extension. */ + /* 23 */ ".objc1_property_list", /* ObjC-1 extension. */ + /* 24 */ ".objc1_protocol_ext" /* ObjC-1 extension. */ +}; + +/* This currently does the same as known_sections, but kept separate for + ease of maintenance. */ + +static void +obj_mach_o_objc_section (int sect_index) +{ + segT section; + +#ifdef md_flush_pending_output + md_flush_pending_output (); +#endif + + section = obj_mach_o_segT_from_bfd_name (objc_sections[sect_index], 1); + if (section != NULL) + { + obj_mach_o_seen_objc_section = 1; /* We need to ensure that certain + sections are present and in the + right order. */ + subseg_set (section, 0); + } + + /* else, we leave the section as it was; there was a fatal error anyway. */ +} + +/* Debug section directives. */ + +static const char * const debug_sections[] = +{ + /* 0 */ NULL, + /* __DWARF */ + /* 1 */ ".debug_frame", + /* 2 */ ".debug_info", + /* 3 */ ".debug_abbrev", + /* 4 */ ".debug_aranges", + /* 5 */ ".debug_macinfo", + /* 6 */ ".debug_line", + /* 7 */ ".debug_loc", + /* 8 */ ".debug_pubnames", + /* 9 */ ".debug_pubtypes", + /* 10 */ ".debug_str", + /* 11 */ ".debug_ranges", + /* 12 */ ".debug_macro" +}; + +/* ??? Maybe these should be conditional on gdwarf-*. + It`s also likely that we will need to be able to set them from the cfi + code. */ + +static void +obj_mach_o_debug_section (int sect_index) +{ + segT section; + +#ifdef md_flush_pending_output + md_flush_pending_output (); +#endif + + section = obj_mach_o_segT_from_bfd_name (debug_sections[sect_index], 1); + if (section != NULL) + subseg_set (section, 0); + + /* else, we leave the section as it was; there was a fatal error anyway. */ +} + +/* This could be moved to the tc-xx files, but there is so little dependency + there, that the code might as well be shared. */ + +struct opt_tgt_sect +{ + const char *name; + unsigned x86_val; + unsigned ppc_val; +}; + +/* The extensions here are for specific sections that are generated by GCC + and Darwin system tools, but don't have directives in the `system as'. */ + +static const struct opt_tgt_sect tgt_sections[] = +{ + /* 0 */ { NULL, 0, 0}, + /* 1 */ { ".lazy_symbol_pointer", 0, 0}, + /* 2 */ { ".lazy_symbol_pointer2", 0, 0}, /* X86 - extension */ + /* 3 */ { ".lazy_symbol_pointer3", 0, 0}, /* X86 - extension */ + /* 4 */ { ".non_lazy_symbol_pointer", 0, 0}, + /* 5 */ { ".non_lazy_symbol_pointer_x86", 0, 0}, /* X86 - extension */ + /* 6 */ { ".symbol_stub", 16, 20}, + /* 7 */ { ".symbol_stub1", 0, 16}, /* PPC - extension */ + /* 8 */ { ".picsymbol_stub", 26, 36}, + /* 9 */ { ".picsymbol_stub1", 0, 32}, /* PPC - extension */ + /* 10 */ { ".picsymbol_stub2", 25, 0}, /* X86 - extension */ + /* 11 */ { ".picsymbol_stub3", 5, 0}, /* X86 - extension */ +}; + +/* Interface for an optional section directive. */ + +static void +obj_mach_o_opt_tgt_section (int sect_index) +{ + const struct opt_tgt_sect *tgtsct = &tgt_sections[sect_index]; + segT section; + +#ifdef md_flush_pending_output + md_flush_pending_output (); +#endif + + section = obj_mach_o_segT_from_bfd_name (tgtsct->name, 0); + if (section == NULL) + { + as_bad (_("%s is not used for the selected target"), tgtsct->name); + /* Leave the section as it is. */ + } + else + { + bfd_mach_o_section *mo_sec = bfd_mach_o_get_mach_o_section (section); + subseg_set (section, 0); +#if defined (TC_I386) + mo_sec->reserved2 = tgtsct->x86_val; +#elif defined (TC_PPC) + mo_sec->reserved2 = tgtsct->ppc_val; +#else + mo_sec->reserved2 = 0; +#endif + } +} + +/* We don't necessarily have the three 'base' sections on mach-o. + Normally, we would start up with only the 'text' section defined. + However, even that can be suppressed with (TODO) c/l option "-n". + Thus, we have to be able to create all three sections on-demand. */ + +static void +obj_mach_o_base_section (int sect_index) +{ + segT section; + +#ifdef md_flush_pending_output + md_flush_pending_output (); +#endif + + /* We don't support numeric (or any other) qualifications on the + well-known section shorthands. */ + demand_empty_rest_of_line (); + + switch (sect_index) + { + /* Handle the three sections that are globally known within GAS. + For Mach-O, these are created on demand rather than at startup. */ + case 1: + if (text_section == NULL) + text_section = obj_mach_o_segT_from_bfd_name (TEXT_SECTION_NAME, 1); + if (obj_mach_o_is_static) + { + bfd_mach_o_section *mo_sec + = bfd_mach_o_get_mach_o_section (text_section); + mo_sec->flags &= ~BFD_MACH_O_S_ATTR_PURE_INSTRUCTIONS; + } + section = text_section; + break; + case 2: + if (data_section == NULL) + data_section = obj_mach_o_segT_from_bfd_name (DATA_SECTION_NAME, 1); + section = data_section; + break; + case 3: + /* ??? maybe this achieves very little, as an addition. */ + if (bss_section == NULL) + { + bss_section = obj_mach_o_segT_from_bfd_name (BSS_SECTION_NAME, 1); + seg_info (bss_section)->bss = 1; + } + section = bss_section; + break; + default: + as_fatal (_("internal error: base section index out of range")); + return; + break; + } + subseg_set (section, 0); +} + +/* This finishes off parsing a .comm or .lcomm statement, which both can have + an (optional) alignment field. It also allows us to create the bss section + on demand. */ + +static symbolS * +obj_mach_o_common_parse (int is_local, symbolS *symbolP, + addressT size) +{ + addressT align = 0; + bfd_mach_o_asymbol *s; + + SKIP_WHITESPACE (); + + /* Both comm and lcomm take an optional alignment, as a power + of two between 1 and 15. */ + if (*input_line_pointer == ',') + { + /* We expect a power of 2. */ + align = parse_align (0); + if (align == (addressT) -1) + return NULL; + if (align > 15) + { + as_warn (_("Alignment (%lu) too large: 15 assumed."), + (unsigned long)align); + align = 15; + } + } + + s = (bfd_mach_o_asymbol *) symbol_get_bfdsym (symbolP); + if (is_local) + { + /* Create the BSS section on demand. */ + if (bss_section == NULL) + { + bss_section = obj_mach_o_segT_from_bfd_name (BSS_SECTION_NAME, 1); + seg_info (bss_section)->bss = 1; + } + bss_alloc (symbolP, size, align); + s->n_type = BFD_MACH_O_N_SECT; + S_CLEAR_EXTERNAL (symbolP); + } + else + { + S_SET_VALUE (symbolP, size); + S_SET_ALIGN (symbolP, align); + S_SET_EXTERNAL (symbolP); + S_SET_SEGMENT (symbolP, bfd_com_section_ptr); + s->n_type = BFD_MACH_O_N_UNDF | BFD_MACH_O_N_EXT; + } + + /* This is a data object (whatever we choose that to mean). */ + s->symbol.flags |= BSF_OBJECT; + + /* We've set symbol qualifiers, so validate if you can. */ + s->symbol.udata.i = SYM_MACHO_FIELDS_NOT_VALIDATED; + + return symbolP; +} + +static void +obj_mach_o_comm (int is_local) +{ + s_comm_internal (is_local, obj_mach_o_common_parse); +} + +/* Set properties that apply to the whole file. At present, the only + one defined, is subsections_via_symbols. */ + +typedef enum obj_mach_o_file_properties { + OBJ_MACH_O_FILE_PROP_NONE = 0, + OBJ_MACH_O_FILE_PROP_SUBSECTS_VIA_SYMS, + OBJ_MACH_O_FILE_PROP_MAX +} obj_mach_o_file_properties; + +static void +obj_mach_o_fileprop (int prop) +{ + if (prop < 0 || prop >= OBJ_MACH_O_FILE_PROP_MAX) + as_fatal (_("internal error: bad file property ID %d"), prop); + + switch ((obj_mach_o_file_properties) prop) + { + case OBJ_MACH_O_FILE_PROP_SUBSECTS_VIA_SYMS: + obj_mach_o_subsections_by_symbols = 1; + if (!bfd_set_private_flags (stdoutput, + BFD_MACH_O_MH_SUBSECTIONS_VIA_SYMBOLS)) + as_bad (_("failed to set subsections by symbols")); + demand_empty_rest_of_line (); + break; + default: + break; + } +} + +/* Temporary markers for symbol reference data. + Lazy will remain in place. */ +#define LAZY 0x01 +#define REFE 0x02 + +/* We have a bunch of qualifiers that may be applied to symbols. + .globl is handled here so that we might make sure that conflicting qualifiers + are caught where possible. */ + +typedef enum obj_mach_o_symbol_type { + OBJ_MACH_O_SYM_UNK = 0, + OBJ_MACH_O_SYM_LOCAL = 1, + OBJ_MACH_O_SYM_GLOBL = 2, + OBJ_MACH_O_SYM_REFERENCE = 3, + OBJ_MACH_O_SYM_WEAK_REF = 4, + OBJ_MACH_O_SYM_LAZY_REF = 5, + OBJ_MACH_O_SYM_WEAK_DEF = 6, + OBJ_MACH_O_SYM_PRIV_EXT = 7, + OBJ_MACH_O_SYM_NO_DEAD_STRIP = 8, + OBJ_MACH_O_SYM_WEAK = 9 +} obj_mach_o_symbol_type; + +/* Set Mach-O-specific symbol qualifiers. */ + +static int +obj_mach_o_set_symbol_qualifier (symbolS *sym, int type) +{ + int is_defined; + bfd_mach_o_asymbol *s = (bfd_mach_o_asymbol *) symbol_get_bfdsym (sym); + bfd_mach_o_section *sec; + int sectype = -1; + int err = 0; + + /* If the symbol is defined, then we can do more rigorous checking on + the validity of the qualifiers. Otherwise, we are stuck with waiting + until it's defined - or until write the file. + + In certain cases (e.g. when a symbol qualifier is intended to introduce + an undefined symbol in a stubs section) we should check that the current + section is appropriate to the qualifier. */ + + is_defined = s->symbol.section != bfd_und_section_ptr; + if (is_defined) + sec = bfd_mach_o_get_mach_o_section (s->symbol.section) ; + else + sec = bfd_mach_o_get_mach_o_section (now_seg) ; + + if (sec != NULL) + sectype = sec->flags & BFD_MACH_O_SECTION_TYPE_MASK; + + switch ((obj_mach_o_symbol_type) type) + { + case OBJ_MACH_O_SYM_LOCAL: + /* This is an extension over the system tools. */ + if (s->n_type & (BFD_MACH_O_N_PEXT | BFD_MACH_O_N_EXT)) + { + as_bad (_("'%s' previously declared as '%s'."), s->symbol.name, + (s->n_type & BFD_MACH_O_N_PEXT) ? "private extern" + : "global" ); + err = 1; + } + else + { + s->n_type &= ~BFD_MACH_O_N_EXT; + S_CLEAR_EXTERNAL (sym); + } + break; + + case OBJ_MACH_O_SYM_PRIV_EXT: + s->n_type |= BFD_MACH_O_N_PEXT ; + s->n_desc &= ~LAZY; /* The native tool switches this off too. */ + /* We follow the system tools in marking PEXT as also global. */ + /* Fall through. */ + + case OBJ_MACH_O_SYM_GLOBL: + /* It's not an error to define a symbol and then make it global. */ + s->n_type |= BFD_MACH_O_N_EXT; + S_SET_EXTERNAL (sym); + break; + + case OBJ_MACH_O_SYM_REFERENCE: + if (is_defined) + s->n_desc |= BFD_MACH_O_N_NO_DEAD_STRIP; + else + s->n_desc |= (REFE | BFD_MACH_O_N_NO_DEAD_STRIP); + break; + + case OBJ_MACH_O_SYM_LAZY_REF: + if (is_defined) + s->n_desc |= BFD_MACH_O_N_NO_DEAD_STRIP; + else + s->n_desc |= (REFE | LAZY | BFD_MACH_O_N_NO_DEAD_STRIP); + break; + + /* Force ld to retain the symbol - even if it appears unused. */ + case OBJ_MACH_O_SYM_NO_DEAD_STRIP: + s->n_desc |= BFD_MACH_O_N_NO_DEAD_STRIP ; + break; + + /* Mach-O's idea of weak ... */ + case OBJ_MACH_O_SYM_WEAK_REF: + s->n_desc |= BFD_MACH_O_N_WEAK_REF ; + break; + + case OBJ_MACH_O_SYM_WEAK_DEF: + if (is_defined && sectype != BFD_MACH_O_S_COALESCED) + { + as_bad (_("'%s' can't be a weak_definition (currently only" + " supported in sections of type coalesced)"), + s->symbol.name); + err = 1; + } + else + s->n_desc |= BFD_MACH_O_N_WEAK_DEF; + break; + + case OBJ_MACH_O_SYM_WEAK: + /* A generic 'weak' - we try to figure out what it means at + symbol frob time. */ + S_SET_WEAK (sym); + break; + + default: + break; + } + + /* We've seen some kind of qualifier - check validity if or when the entity + is defined. */ + s->symbol.udata.i = SYM_MACHO_FIELDS_NOT_VALIDATED; + return err; +} + +/* Respond to symbol qualifiers. + All of the form: + .<qualifier> symbol [, symbol]* + a list of symbols is an extension over the Darwin system as. */ + +static void +obj_mach_o_sym_qual (int ntype) +{ + char *name; + char c; + symbolS *symbolP; + +#ifdef md_flush_pending_output + md_flush_pending_output (); +#endif + + do + { + name = input_line_pointer; + c = get_symbol_end (); + symbolP = symbol_find_or_make (name); + obj_mach_o_set_symbol_qualifier (symbolP, ntype); + *input_line_pointer = c; + SKIP_WHITESPACE (); + c = *input_line_pointer; + if (c == ',') + { + input_line_pointer++; + SKIP_WHITESPACE (); + if (is_end_of_line[(unsigned char) *input_line_pointer]) + c = '\n'; + } + } + while (c == ','); + + demand_empty_rest_of_line (); +} + +typedef struct obj_mach_o_indirect_sym +{ + symbolS *sym; + segT sect; + struct obj_mach_o_indirect_sym *next; +} obj_mach_o_indirect_sym; + +/* We store in order an maintain a pointer to the last one - to save reversing + later. */ +obj_mach_o_indirect_sym *indirect_syms; +obj_mach_o_indirect_sym *indirect_syms_tail; + +static void +obj_mach_o_indirect_symbol (int arg ATTRIBUTE_UNUSED) +{ + bfd_mach_o_section *sec = bfd_mach_o_get_mach_o_section (now_seg); + +#ifdef md_flush_pending_output + md_flush_pending_output (); +#endif + + if (obj_mach_o_is_static) + as_bad (_("use of .indirect_symbols requires `-dynamic'")); + + switch (sec->flags & BFD_MACH_O_SECTION_TYPE_MASK) + { + case BFD_MACH_O_S_SYMBOL_STUBS: + case BFD_MACH_O_S_LAZY_SYMBOL_POINTERS: + case BFD_MACH_O_S_NON_LAZY_SYMBOL_POINTERS: + { + obj_mach_o_indirect_sym *isym; + char *name = input_line_pointer; + char c = get_symbol_end (); + symbolS *sym = symbol_find_or_make (name); + unsigned int elsize = + bfd_mach_o_section_get_entry_size (stdoutput, sec); + + if (elsize == 0) + { + as_bad (_("attempt to add an indirect_symbol to a stub or" + " reference section with a zero-sized element at %s"), + name); + *input_line_pointer = c; + ignore_rest_of_line (); + return; + } + *input_line_pointer = c; + + /* The indirect symbols are validated after the symbol table is + frozen, we must make sure that if a local symbol is used as an + indirect, it is promoted to a 'real' one. Fetching the bfd sym + achieves this. */ + symbol_get_bfdsym (sym); + isym = (obj_mach_o_indirect_sym *) + xmalloc (sizeof (obj_mach_o_indirect_sym)); + + /* Just record the data for now, we will validate it when we + compute the output in obj_mach_o_set_indirect_symbols. */ + isym->sym = sym; + isym->sect = now_seg; + isym->next = NULL; + if (indirect_syms == NULL) + indirect_syms = isym; + else + indirect_syms_tail->next = isym; + indirect_syms_tail = isym; + } + break; + + default: + as_bad (_("an .indirect_symbol must be in a symbol pointer" + " or stub section.")); + ignore_rest_of_line (); + return; + } + demand_empty_rest_of_line (); +} + +const pseudo_typeS mach_o_pseudo_table[] = +{ + /* Section directives. */ + { "comm", obj_mach_o_comm, 0 }, + { "lcomm", obj_mach_o_comm, 1 }, + + { "text", obj_mach_o_base_section, 1}, + { "data", obj_mach_o_base_section, 2}, + { "bss", obj_mach_o_base_section, 3}, /* extension */ + + { "const", obj_mach_o_known_section, 1}, + { "static_const", obj_mach_o_known_section, 2}, + { "cstring", obj_mach_o_known_section, 3}, + { "literal4", obj_mach_o_known_section, 4}, + { "literal8", obj_mach_o_known_section, 5}, + { "literal16", obj_mach_o_known_section, 6}, + { "constructor", obj_mach_o_known_section, 7}, + { "destructor", obj_mach_o_known_section, 8}, + { "eh_frame", obj_mach_o_known_section, 9}, + + { "const_data", obj_mach_o_known_section, 10}, + { "static_data", obj_mach_o_known_section, 11}, + { "mod_init_func", obj_mach_o_known_section, 12}, + { "mod_term_func", obj_mach_o_known_section, 13}, + { "dyld", obj_mach_o_known_section, 14}, + { "cfstring", obj_mach_o_known_section, 15}, + + { "objc_class", obj_mach_o_objc_section, 1}, + { "objc_meta_class", obj_mach_o_objc_section, 2}, + { "objc_cat_cls_meth", obj_mach_o_objc_section, 3}, + { "objc_cat_inst_meth", obj_mach_o_objc_section, 4}, + { "objc_protocol", obj_mach_o_objc_section, 5}, + { "objc_string_object", obj_mach_o_objc_section, 6}, + { "objc_cls_meth", obj_mach_o_objc_section, 7}, + { "objc_inst_meth", obj_mach_o_objc_section, 8}, + { "objc_cls_refs", obj_mach_o_objc_section, 9}, + { "objc_message_refs", obj_mach_o_objc_section, 10}, + { "objc_symbols", obj_mach_o_objc_section, 11}, + { "objc_category", obj_mach_o_objc_section, 12}, + { "objc_class_vars", obj_mach_o_objc_section, 13}, + { "objc_instance_vars", obj_mach_o_objc_section, 14}, + { "objc_module_info", obj_mach_o_objc_section, 15}, + { "objc_class_names", obj_mach_o_objc_section, 16}, /* Alias for .cstring */ + { "objc_meth_var_types", obj_mach_o_objc_section, 17}, /* Alias for .cstring */ + { "objc_meth_var_names", obj_mach_o_objc_section, 18}, /* Alias for .cstring */ + { "objc_selector_strs", obj_mach_o_objc_section, 19}, + { "objc_image_info", obj_mach_o_objc_section, 20}, /* extension. */ + { "objc_selector_fixup", obj_mach_o_objc_section, 21}, /* extension. */ + { "objc1_class_ext", obj_mach_o_objc_section, 22}, /* ObjC-1 extension. */ + { "objc1_property_list", obj_mach_o_objc_section, 23}, /* ObjC-1 extension. */ + { "objc1_protocol_ext", obj_mach_o_objc_section, 24}, /* ObjC-1 extension. */ + + { "debug_frame", obj_mach_o_debug_section, 1}, /* extension. */ + { "debug_info", obj_mach_o_debug_section, 2}, /* extension. */ + { "debug_abbrev", obj_mach_o_debug_section, 3}, /* extension. */ + { "debug_aranges", obj_mach_o_debug_section, 4}, /* extension. */ + { "debug_macinfo", obj_mach_o_debug_section, 5}, /* extension. */ + { "debug_line", obj_mach_o_debug_section, 6}, /* extension. */ + { "debug_loc", obj_mach_o_debug_section, 7}, /* extension. */ + { "debug_pubnames", obj_mach_o_debug_section, 8}, /* extension. */ + { "debug_pubtypes", obj_mach_o_debug_section, 9}, /* extension. */ + { "debug_str", obj_mach_o_debug_section, 10}, /* extension. */ + { "debug_ranges", obj_mach_o_debug_section, 11}, /* extension. */ + { "debug_macro", obj_mach_o_debug_section, 12}, /* extension. */ + + { "lazy_symbol_pointer", obj_mach_o_opt_tgt_section, 1}, + { "lazy_symbol_pointer2", obj_mach_o_opt_tgt_section, 2}, /* extension. */ + { "lazy_symbol_pointer3", obj_mach_o_opt_tgt_section, 3}, /* extension. */ + { "non_lazy_symbol_pointer", obj_mach_o_opt_tgt_section, 4}, + { "non_lazy_symbol_pointer_x86", obj_mach_o_opt_tgt_section, 5}, /* extension. */ + { "symbol_stub", obj_mach_o_opt_tgt_section, 6}, + { "symbol_stub1", obj_mach_o_opt_tgt_section, 7}, /* extension. */ + { "picsymbol_stub", obj_mach_o_opt_tgt_section, 8}, /* extension. */ + { "picsymbol_stub1", obj_mach_o_opt_tgt_section, 9}, /* extension. */ + { "picsymbol_stub2", obj_mach_o_opt_tgt_section, 4}, /* extension. */ + { "picsymbol_stub3", obj_mach_o_opt_tgt_section, 4}, /* extension. */ + + { "section", obj_mach_o_section, 0}, + { "zerofill", obj_mach_o_zerofill, 0}, + + /* Symbol qualifiers. */ + {"local", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_LOCAL}, + {"globl", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_GLOBL}, + {"reference", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_REFERENCE}, + {"weak_reference", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_WEAK_REF}, + {"lazy_reference", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_LAZY_REF}, + {"weak_definition", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_WEAK_DEF}, + {"private_extern", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_PRIV_EXT}, + {"no_dead_strip", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_NO_DEAD_STRIP}, + {"weak", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_WEAK}, /* ext */ + + { "indirect_symbol", obj_mach_o_indirect_symbol, 0}, + + /* File flags. */ + { "subsections_via_symbols", obj_mach_o_fileprop, + OBJ_MACH_O_FILE_PROP_SUBSECTS_VIA_SYMS}, + + {NULL, NULL, 0} +}; + +/* Determine the default n_type value for a symbol from its section. */ + +static unsigned +obj_mach_o_type_for_symbol (bfd_mach_o_asymbol *s) +{ + if (s->symbol.section == bfd_abs_section_ptr) + return BFD_MACH_O_N_ABS; + else if (s->symbol.section == bfd_com_section_ptr + || s->symbol.section == bfd_und_section_ptr) + return BFD_MACH_O_N_UNDF; + else + return BFD_MACH_O_N_SECT; +} + +void +obj_mach_o_frob_colon (const char *name) +{ + if (!bfd_is_local_label_name (stdoutput, name)) + { + /* A non-local label will create a new subsection, so start a new + frag. */ + frag_wane (frag_now); + frag_new (0); + } +} + +/* We need to check the correspondence between some kinds of symbols and their + sections. Common and BSS vars will seen via the obj_macho_comm() function. + + The earlier we can pick up a problem, the better the diagnostics will be. + + However, when symbol type information is attached, the symbol section will + quite possibly be unknown. So we are stuck with checking (most of the) + validity at the time the file is written (unfortunately, then one doesn't + get line number information in the diagnostic). */ + +/* Here we pick up the case where symbol qualifiers have been applied that + are possibly incompatible with the section etc. that the symbol is defined + in. */ + +void obj_mach_o_frob_label (struct symbol *sp) +{ + bfd_mach_o_asymbol *s; + unsigned base_type; + bfd_mach_o_section *sec; + int sectype = -1; + + if (!bfd_is_local_label_name (stdoutput, S_GET_NAME (sp))) + { + /* If this is a non-local label, it should have started a new sub- + section. */ + gas_assert (frag_now->obj_frag_data.subsection == NULL); + frag_now->obj_frag_data.subsection = sp; + } + + /* Leave local symbols alone. */ + + if (S_IS_LOCAL (sp)) + return; + + s = (bfd_mach_o_asymbol *) symbol_get_bfdsym (sp); + /* Leave debug symbols alone. */ + if ((s->n_type & BFD_MACH_O_N_STAB) != 0) + return; + + /* This is the base symbol type, that we mask in. */ + base_type = obj_mach_o_type_for_symbol (s); + + sec = bfd_mach_o_get_mach_o_section (s->symbol.section); + if (sec != NULL) + sectype = sec->flags & BFD_MACH_O_SECTION_TYPE_MASK; + + /* If there is a pre-existing qualifier, we can make some checks about + validity now. */ + + if(s->symbol.udata.i == SYM_MACHO_FIELDS_NOT_VALIDATED) + { + if ((s->n_desc & BFD_MACH_O_N_WEAK_DEF) + && sectype != BFD_MACH_O_S_COALESCED) + as_bad (_("'%s' can't be a weak_definition (currently only supported" + " in sections of type coalesced)"), s->symbol.name); + + /* Have we changed from an undefined to defined ref? */ + s->n_desc &= ~(REFE | LAZY); + } + + s->n_type &= ~BFD_MACH_O_N_TYPE; + s->n_type |= base_type; +} + +/* This is the fall-back, we come here when we get to the end of the file and + the symbol is not defined - or there are combinations of qualifiers required + (e.g. global + weak_def). */ + +int +obj_mach_o_frob_symbol (struct symbol *sp) +{ + bfd_mach_o_asymbol *s; + unsigned base_type; + bfd_mach_o_section *sec; + int sectype = -1; + + /* Leave local symbols alone. */ + if (S_IS_LOCAL (sp)) + return 0; + + s = (bfd_mach_o_asymbol *) symbol_get_bfdsym (sp); + /* Leave debug symbols alone. */ + if ((s->n_type & BFD_MACH_O_N_STAB) != 0) + return 0; + + base_type = obj_mach_o_type_for_symbol (s); + sec = bfd_mach_o_get_mach_o_section (s->symbol.section); + if (sec != NULL) + sectype = sec->flags & BFD_MACH_O_SECTION_TYPE_MASK; + + if (s->symbol.section == bfd_und_section_ptr) + { + /* ??? Do we really gain much from implementing this as well as the + mach-o specific ones? */ + if (s->symbol.flags & BSF_WEAK) + s->n_desc |= BFD_MACH_O_N_WEAK_REF; + + /* Undefined syms, become extern. */ + s->n_type |= BFD_MACH_O_N_EXT; + S_SET_EXTERNAL (sp); + } + else if (s->symbol.section == bfd_com_section_ptr) + { + /* ... so do comm. */ + s->n_type |= BFD_MACH_O_N_EXT; + S_SET_EXTERNAL (sp); + } + else + { + if ((s->symbol.flags & BSF_WEAK) + && (sectype == BFD_MACH_O_S_COALESCED) + && (s->n_type & (BFD_MACH_O_N_PEXT | BFD_MACH_O_N_EXT))) + s->n_desc |= BFD_MACH_O_N_WEAK_DEF; +/* ??? we should do this - but then that reveals that the semantics of weak + are different from what's supported in mach-o object files. + else + as_bad (_("'%s' can't be a weak_definition."), + s->symbol.name); */ + } + + if (s->symbol.udata.i == SYM_MACHO_FIELDS_UNSET) + { + /* Anything here that should be added that is non-standard. */ + s->n_desc &= ~BFD_MACH_O_REFERENCE_MASK; + s->symbol.udata.i = SYM_MACHO_FIELDS_NOT_VALIDATED; + } + else if (s->symbol.udata.i == SYM_MACHO_FIELDS_NOT_VALIDATED) + { + /* Try to validate any combinations. */ + if (s->n_desc & BFD_MACH_O_N_WEAK_DEF) + { + if (s->symbol.section == bfd_und_section_ptr) + as_bad (_("'%s' can't be a weak_definition (since it is" + " undefined)"), s->symbol.name); + else if (sectype != BFD_MACH_O_S_COALESCED) + as_bad (_("'%s' can't be a weak_definition (currently only supported" + " in sections of type coalesced)"), s->symbol.name); + else if (! (s->n_type & (BFD_MACH_O_N_PEXT | BFD_MACH_O_N_EXT))) + as_bad (_("Non-global symbol: '%s' can't be a weak_definition."), + s->symbol.name); + } + + } + else + as_bad (_("internal error: [%s] unexpected code [%lx] in frob symbol"), + s->symbol.name, (unsigned long)s->symbol.udata.i); + + s->n_type &= ~BFD_MACH_O_N_TYPE; + s->n_type |= base_type; + + if (s->symbol.flags & BSF_GLOBAL) + s->n_type |= BFD_MACH_O_N_EXT; + + /* This cuts both ways - we promote some things to external above. */ + if (s->n_type & (BFD_MACH_O_N_PEXT | BFD_MACH_O_N_EXT)) + S_SET_EXTERNAL (sp); + + return 0; +} + +/* Support stabs for mach-o. */ + +void +obj_mach_o_process_stab (int what, const char *string, + int type, int other, int desc) +{ + symbolS *symbolP; + bfd_mach_o_asymbol *s; + + switch (what) + { + case 'd': + symbolP = symbol_new ("", now_seg, frag_now_fix (), frag_now); + /* Special stabd NULL name indicator. */ + S_SET_NAME (symbolP, NULL); + break; + + case 'n': + case 's': + symbolP = symbol_new (string, undefined_section, (valueT) 0, + &zero_address_frag); + pseudo_set (symbolP); + break; + + default: + as_bad(_("unrecognized stab type '%c'"), (char)what); + abort (); + break; + } + + s = (bfd_mach_o_asymbol *) symbol_get_bfdsym (symbolP); + s->n_type = type; + s->n_desc = desc; + /* For stabd, this will eventually get overwritten by the section number. */ + s->n_sect = other; + + /* It's a debug symbol. */ + s->symbol.flags |= BSF_DEBUGGING; + + /* We've set it - so check it, if you can, but don't try to create the + flags. */ + s->symbol.udata.i = SYM_MACHO_FIELDS_NOT_VALIDATED; +} + +/* This is a place to check for any errors that we can't detect until we know + what remains undefined at the end of assembly. */ + +static void +obj_mach_o_check_before_writing (bfd *abfd ATTRIBUTE_UNUSED, + asection *sec, + void *unused ATTRIBUTE_UNUSED) +{ + fixS *fixP; + struct frchain *frchp; + segment_info_type *seginfo = seg_info (sec); + + if (seginfo == NULL) + return; + + /* We are not allowed subtractions where either of the operands is + undefined. So look through the frags for any fixes to check. */ + for (frchp = seginfo->frchainP; frchp != NULL; frchp = frchp->frch_next) + for (fixP = frchp->fix_root; fixP != NULL; fixP = fixP->fx_next) + { + if (fixP->fx_addsy != NULL + && fixP->fx_subsy != NULL + && (! S_IS_DEFINED (fixP->fx_addsy) + || ! S_IS_DEFINED (fixP->fx_subsy))) + { + segT add_symbol_segment = S_GET_SEGMENT (fixP->fx_addsy); + segT sub_symbol_segment = S_GET_SEGMENT (fixP->fx_subsy); + + if (! S_IS_DEFINED (fixP->fx_addsy) + && S_IS_DEFINED (fixP->fx_subsy)) + { + as_bad_where (fixP->fx_file, fixP->fx_line, + _("`%s' can't be undefined in `%s' - `%s' {%s section}"), + S_GET_NAME (fixP->fx_addsy), S_GET_NAME (fixP->fx_addsy), + S_GET_NAME (fixP->fx_subsy), segment_name (sub_symbol_segment)); + } + else if (! S_IS_DEFINED (fixP->fx_subsy) + && S_IS_DEFINED (fixP->fx_addsy)) + { + as_bad_where (fixP->fx_file, fixP->fx_line, + _("`%s' can't be undefined in `%s' {%s section} - `%s'"), + S_GET_NAME (fixP->fx_subsy), S_GET_NAME (fixP->fx_addsy), + segment_name (add_symbol_segment), S_GET_NAME (fixP->fx_subsy)); + } + else + { + as_bad_where (fixP->fx_file, fixP->fx_line, + _("`%s' and `%s' can't be undefined in `%s' - `%s'"), + S_GET_NAME (fixP->fx_addsy), S_GET_NAME (fixP->fx_subsy), + S_GET_NAME (fixP->fx_addsy), S_GET_NAME (fixP->fx_subsy)); + } + } + } +} + +/* Do any checks that we can't complete without knowing what's undefined. */ +void +obj_mach_o_pre_output_hook (void) +{ + bfd_map_over_sections (stdoutput, obj_mach_o_check_before_writing, (char *) 0); +} + +/* Here we count up frags in each subsection (where a sub-section is defined + as starting with a non-local symbol). + Note that, if there are no non-local symbols in a section, all the frags will + be attached as one anonymous subsection. */ + +static void +obj_mach_o_set_subsections (bfd *abfd ATTRIBUTE_UNUSED, + asection *sec, + void *unused ATTRIBUTE_UNUSED) +{ + segment_info_type *seginfo = seg_info (sec); + symbolS *cur_subsection = NULL; + struct obj_mach_o_symbol_data *cur_subsection_data = NULL; + fragS *frag; + frchainS *chain; + + /* Protect against sections not created by gas. */ + if (seginfo == NULL) + return; + + /* Attach every frag to a subsection. */ + for (chain = seginfo->frchainP; chain != NULL; chain = chain->frch_next) + for (frag = chain->frch_root; frag != NULL; frag = frag->fr_next) + { + if (frag->obj_frag_data.subsection == NULL) + frag->obj_frag_data.subsection = cur_subsection; + else + { + cur_subsection = frag->obj_frag_data.subsection; + cur_subsection_data = symbol_get_obj (cur_subsection); + cur_subsection_data->subsection_size = 0; + } + if (cur_subsection_data != NULL) + { + /* Update subsection size. */ + cur_subsection_data->subsection_size += frag->fr_fix; + } + } +} + +/* Handle mach-o subsections-via-symbols counting up frags belonging to each + sub-section. */ + +void +obj_mach_o_pre_relax_hook (void) +{ + bfd_map_over_sections (stdoutput, obj_mach_o_set_subsections, (char *) 0); +} + +/* Zerofill and GB Zerofill sections must be sorted to follow all other + sections in their segments. + + The native 'as' leaves the sections physically in the order they appear in + the source, and adjusts the section VMAs to meet the constraint. + + We follow this for now - if nothing else, it makes comparison easier. + + An alternative implementation would be to sort the sections as ld requires. + It might be advantageous to implement such a scheme in the future (or even + to make the style of section ordering user-selectable). */ + +typedef struct obj_mach_o_set_vma_data +{ + bfd_vma vma; + unsigned vma_pass; + unsigned zerofill_seen; + unsigned gb_zerofill_seen; +} obj_mach_o_set_vma_data; + +/* We do (possibly) three passes through to set the vma, so that: + + zerofill sections get VMAs after all others in their segment + GB zerofill get VMAs last. + + As we go, we notice if we see any Zerofill or GB Zerofill sections, so that + we can skip the additional passes if there's nothing to do. */ + +static void +obj_mach_o_set_section_vma (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *v_p) +{ + bfd_mach_o_section *ms = bfd_mach_o_get_mach_o_section (sec); + unsigned bfd_align = bfd_get_section_alignment (abfd, sec); + obj_mach_o_set_vma_data *p = (struct obj_mach_o_set_vma_data *)v_p; + unsigned sectype = (ms->flags & BFD_MACH_O_SECTION_TYPE_MASK); + unsigned zf; + + zf = 0; + if (sectype == BFD_MACH_O_S_ZEROFILL) + { + zf = 1; + p->zerofill_seen = zf; + } + else if (sectype == BFD_MACH_O_S_GB_ZEROFILL) + { + zf = 2; + p->gb_zerofill_seen = zf; + } + + if (p->vma_pass != zf) + return; + + /* We know the section size now - so make a vma for the section just + based on order. */ + ms->size = bfd_get_section_size (sec); + + /* Make sure that the align agrees, and set to the largest value chosen. */ + ms->align = ms->align > bfd_align ? ms->align : bfd_align; + bfd_set_section_alignment (abfd, sec, ms->align); + + p->vma += (1 << ms->align) - 1; + p->vma &= ~((1 << ms->align) - 1); + ms->addr = p->vma; + bfd_set_section_vma (abfd, sec, p->vma); + p->vma += ms->size; +} + +/* (potentially) three passes over the sections, setting VMA. We skip the + {gb}zerofill passes if we didn't see any of the relevant sections. */ + +void obj_mach_o_post_relax_hook (void) +{ + obj_mach_o_set_vma_data d; + + memset (&d, 0, sizeof (d)); + + bfd_map_over_sections (stdoutput, obj_mach_o_set_section_vma, (char *) &d); + if ((d.vma_pass = d.zerofill_seen) != 0) + bfd_map_over_sections (stdoutput, obj_mach_o_set_section_vma, (char *) &d); + if ((d.vma_pass = d.gb_zerofill_seen) != 0) + bfd_map_over_sections (stdoutput, obj_mach_o_set_section_vma, (char *) &d); +} + +static void +obj_mach_o_set_indirect_symbols (bfd *abfd, asection *sec, + void *xxx ATTRIBUTE_UNUSED) +{ + bfd_vma sect_size = bfd_section_size (abfd, sec); + bfd_mach_o_section *ms = bfd_mach_o_get_mach_o_section (sec); + unsigned lazy = 0; + + /* See if we have any indirect syms to consider. */ + if (indirect_syms == NULL) + return; + + /* Process indirect symbols. + Check for errors, if OK attach them as a flat array to the section + for which they are defined. */ + + switch (ms->flags & BFD_MACH_O_SECTION_TYPE_MASK) + { + case BFD_MACH_O_S_SYMBOL_STUBS: + case BFD_MACH_O_S_LAZY_SYMBOL_POINTERS: + lazy = LAZY; + /* Fall through. */ + case BFD_MACH_O_S_NON_LAZY_SYMBOL_POINTERS: + { + unsigned int nactual = 0; + unsigned int ncalc; + obj_mach_o_indirect_sym *isym; + obj_mach_o_indirect_sym *list = NULL; + obj_mach_o_indirect_sym *list_tail = NULL; + unsigned long eltsiz = + bfd_mach_o_section_get_entry_size (abfd, ms); + + for (isym = indirect_syms; isym != NULL; isym = isym->next) + { + if (isym->sect == sec) + { + nactual++; + if (list == NULL) + list = isym; + else + list_tail->next = isym; + list_tail = isym; + } + } + + /* If none are in this section, stop here. */ + if (nactual == 0) + break; + + /* If we somehow added indirect symbols to a section with a zero + entry size, we're dead ... */ + gas_assert (eltsiz != 0); + + ncalc = (unsigned int) (sect_size / eltsiz); + if (nactual != ncalc) + as_bad (_("the number of .indirect_symbols defined in section %s" + " does not match the number expected (%d defined, %d" + " expected)"), sec->name, nactual, ncalc); + else + { + unsigned n; + bfd_mach_o_asymbol *sym; + ms->indirect_syms = + bfd_zalloc (abfd, + nactual * sizeof (bfd_mach_o_asymbol *)); + + if (ms->indirect_syms == NULL) + { + as_fatal (_("internal error: failed to allocate %d indirect" + "symbol pointers"), nactual); + } + + for (isym = list, n = 0; isym != NULL; isym = isym->next, n++) + { + sym = (bfd_mach_o_asymbol *)symbol_get_bfdsym (isym->sym); + /* Array is init to NULL & NULL signals a local symbol + If the section is lazy-bound, we need to keep the + reference to the symbol, since dyld can override. + + Absolute symbols are handled specially. */ + if (sym->symbol.section == bfd_abs_section_ptr) + ms->indirect_syms[n] = sym; + else if (S_IS_LOCAL (isym->sym) && ! lazy) + ; + else + { + if (sym == NULL) + ; + /* If the symbols is external ... */ + else if (S_IS_EXTERNAL (isym->sym) + || (sym->n_type & BFD_MACH_O_N_EXT) + || ! S_IS_DEFINED (isym->sym) + || lazy) + { + sym->n_desc &= ~LAZY; + /* ... it can be lazy, if not defined or hidden. */ + if ((sym->n_type & BFD_MACH_O_N_TYPE) + == BFD_MACH_O_N_UNDF + && ! (sym->n_type & BFD_MACH_O_N_PEXT) + && (sym->n_type & BFD_MACH_O_N_EXT)) + sym->n_desc |= lazy; + ms->indirect_syms[n] = sym; + } + } + } + } + } + break; + + default: + break; + } +} + +/* The process of relocation could alter what's externally visible, thus we + leave setting the indirect symbols until last. */ + +void +obj_mach_o_frob_file_after_relocs (void) +{ + bfd_map_over_sections (stdoutput, obj_mach_o_set_indirect_symbols, (char *) 0); +} + +/* Reverse relocations order to make ld happy. */ + +void +obj_mach_o_reorder_section_relocs (asection *sec, arelent **rels, unsigned int n) +{ + unsigned int i; + unsigned int max = n / 2; + + for (i = 0; i < max; i++) + { + arelent *r = rels[i]; + rels[i] = rels[n - i - 1]; + rels[n - i - 1] = r; + } + bfd_set_reloc (stdoutput, sec, rels, n); +} + +/* Relocation rules are different in frame sections. */ + +static int +obj_mach_o_is_frame_section (segT sec) +{ + int l; + l = strlen (segment_name (sec)); + if ((l == 9 && strncmp (".eh_frame", segment_name (sec), 9) == 0) + || (l == 12 && strncmp (".debug_frame", segment_name (sec), 12) == 0)) + return 1; + return 0; +} + +/* Unless we're in a frame section, we need to force relocs to be generated for + local subtractions. We might eliminate them later (if they are within the + same sub-section) but we don't know that at the point that this decision is + being made. */ + +int +obj_mach_o_allow_local_subtract (expressionS * left ATTRIBUTE_UNUSED, + expressionS * right ATTRIBUTE_UNUSED, + segT seg) +{ + /* Don't interfere if it's one of the GAS internal sections. */ + if (! SEG_NORMAL (seg)) + return 1; + + /* Allow in frame sections, otherwise emit a reloc. */ + return obj_mach_o_is_frame_section (seg); +} + +int +obj_mach_o_in_different_subsection (symbolS *a, symbolS *b) +{ + fragS *fa; + fragS *fb; + + if (S_GET_SEGMENT (a) != S_GET_SEGMENT (b) + || !S_IS_DEFINED (a) + || !S_IS_DEFINED (b)) + { + /* Not in the same segment, or undefined symbol. */ + return 1; + } + + fa = symbol_get_frag (a); + fb = symbol_get_frag (b); + if (fa == NULL || fb == NULL) + { + /* One of the symbols is not in a subsection. */ + return 1; + } + + return fa->obj_frag_data.subsection != fb->obj_frag_data.subsection; +} + +int +obj_mach_o_force_reloc_sub_same (fixS *fix, segT seg) +{ + if (! SEG_NORMAL (seg)) + return 1; + return obj_mach_o_in_different_subsection (fix->fx_addsy, fix->fx_subsy); +} + +int +obj_mach_o_force_reloc_sub_local (fixS *fix, segT seg ATTRIBUTE_UNUSED) +{ + return obj_mach_o_in_different_subsection (fix->fx_addsy, fix->fx_subsy); +} + +int +obj_mach_o_force_reloc (fixS *fix) +{ + if (generic_force_reloc (fix)) + return 1; + + /* Force a reloc if the target is not in the same subsection. + FIXME: handle (a - b) where a and b belongs to the same subsection ? */ + if (fix->fx_addsy != NULL) + { + symbolS *subsec = fix->fx_frag->obj_frag_data.subsection; + symbolS *targ = fix->fx_addsy; + + /* There might be no subsections at all. */ + if (subsec == NULL) + return 0; + + if (S_GET_SEGMENT (targ) == absolute_section) + return 0; + + return obj_mach_o_in_different_subsection (targ, subsec); + } + return 0; +} |