/* subsegs.h -> subsegs.c Copyright 1987, 1992, 1993, 1994, 1995, 1996, 1998, 2000 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 2, 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, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* * For every sub-segment the user mentions in the ASsembler program, * we make one struct frchain. Each sub-segment has exactly one struct frchain * and vice versa. * * Struct frchain's are forward chained (in ascending order of sub-segment * code number). The chain runs through frch_next of each subsegment. * This makes it hard to find a subsegment's frags * if programmer uses a lot of them. Most programs only use text0 and * data0, so they don't suffer. At least this way: * (1) There are no "arbitrary" restrictions on how many subsegments * can be programmed; * (2) Subsegments' frchain-s are (later) chained together in the order in * which they are emitted for object file viz text then data. * * From each struct frchain dangles a chain of struct frags. The frags * represent code fragments, for that sub-segment, forward chained. */ #include "obstack.h" struct frchain /* control building of a frag chain */ { /* FRCH = FRagment CHain control */ struct frag *frch_root; /* 1st struct frag in chain, or NULL */ struct frag *frch_last; /* last struct frag in chain, or NULL */ struct frchain *frch_next; /* next in chain of struct frchain-s */ segT frch_seg; /* SEG_TEXT or SEG_DATA. */ subsegT frch_subseg; /* subsegment number of this chain */ #ifdef BFD_ASSEMBLER fixS *fix_root; /* Root of fixups for this subsegment. */ fixS *fix_tail; /* Last fixup for this subsegment. */ #endif struct obstack frch_obstack; /* for objects in this frag chain */ fragS *frch_frag_now; /* frag_now for this subsegment */ }; typedef struct frchain frchainS; /* All subsegments' chains hang off here. NULL means no frchains yet. */ extern frchainS *frchain_root; /* Frchain we are assembling into now. That is, the current segment's frag chain, even if it contains no (complete) frags. */ extern frchainS *frchain_now; typedef struct segment_info_struct { frchainS *frchainP; unsigned int hadone : 1; /* This field is set if this is a .bss section which does not really have any contents. Once upon a time a .bss section did not have any frags, but that is no longer true. This field prevent the SEC_HAS_CONTENTS flag from being set for the section even if there are frags. */ unsigned int bss : 1; int user_stuff; /* Fixups for this segment. If BFD_ASSEMBLER, this is only valid after the frchains are run together. */ fixS *fix_root; fixS *fix_tail; #if defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER) struct internal_scnhdr scnhdr; enum linkonce_type linkonce; const char *name; #endif symbolS *dot; struct lineno_list *lineno_list_head; struct lineno_list *lineno_list_tail; #ifdef BFD_ASSEMBLER /* Which BFD section does this gas segment correspond to? */ asection *bfd_section; /* NULL, or pointer to the gas symbol that is the section symbol for this section. sym->bsym and bfd_section->symbol should be the same. */ symbolS *sym; #endif union { /* Current size of section holding stabs strings. */ unsigned long stab_string_size; /* Initial frag for ELF. */ char *p; } stabu; #ifdef NEED_LITERAL_POOL unsigned long literal_pool_size; #endif #ifdef TC_SEGMENT_INFO_TYPE TC_SEGMENT_INFO_TYPE tc_segment_info_data; #endif } segment_info_type; #ifdef BFD_ASSEMBLER extern segment_info_type *seg_info (segT); extern symbolS *section_symbol (segT); #else /* ! BFD_ASSEMBLER */ #ifdef MANY_SEGMENTS extern segment_info_type segment_info[]; #define seg_info(SEC) (&segment_info[SEC]) #else /* Sentinel for frchain crawling. Points to the 1st data-segment frchain. (Which is pointed to by the last text-segment frchain.) */ extern frchainS *data0_frchainP; extern frchainS *bss0_frchainP; /* Dummy so stuff can compile. Should never be used. */ struct seg_info_trash { struct { unsigned stab_string_size : 1; } stabu; unsigned hadone : 1; }; #define seg_info(S) (abort (), (struct seg_info_trash *) 0) #endif #endif /* ! BFD_ASSEMBLER */ extern void subsegs_print_statistics (FILE *);