1 /* frags.h - Header file for the frag concept. 2 Copyright 1987, 1992, 1993, 1994, 1995, 1997, 1998, 1999, 2000, 2001, 3 2002, 2003, 2004, 2005, 2006, 2007, 2010, 2011, 2012 4 Free Software Foundation, Inc. 5 6 This file is part of GAS, the GNU Assembler. 7 8 GAS is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 3, or (at your option) 11 any later version. 12 13 GAS is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with GAS; see the file COPYING. If not, write to the Free 20 Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA 21 02110-1301, USA. */ 22 23 #ifndef FRAGS_H 24 #define FRAGS_H 25 26 struct obstack; 27 28 /* A code fragment (frag) is some known number of chars, followed by some 29 unknown number of chars. Typically the unknown number of chars is an 30 instruction address whose size is yet unknown. We always know the greatest 31 possible size the unknown number of chars may become, and reserve that 32 much room at the end of the frag. 33 Once created, frags do not change address during assembly. 34 We chain the frags in (a) forward-linked list(s). The object-file address 35 of the 1st char of a frag is generally not known until after relax(). 36 Many things at assembly time describe an address by {object-file-address 37 of a particular frag}+offset. 38 39 BUG: it may be smarter to have a single pointer off to various different 40 notes for different frag kinds. See how code pans. */ 41 42 struct frag { 43 /* Object file address (as an octet offset). */ 44 addressT fr_address; 45 /* When relaxing multiple times, remember the address the frag had 46 in the last relax pass. */ 47 addressT last_fr_address; 48 49 /* (Fixed) number of octets we know we have. May be 0. */ 50 offsetT fr_fix; 51 /* May be used for (Variable) number of octets after above. 52 The generic frag handling code no longer makes any use of fr_var. */ 53 offsetT fr_var; 54 /* For variable-length tail. */ 55 offsetT fr_offset; 56 /* For variable-length tail. */ 57 symbolS *fr_symbol; 58 /* Points to opcode low addr byte, for relaxation. */ 59 char *fr_opcode; 60 61 /* Chain forward; ascending address order. Rooted in frch_root. */ 62 struct frag *fr_next; 63 64 /* Where the frag was created, or where it became a variant frag. */ 65 char *fr_file; 66 unsigned int fr_line; 67 68 #ifndef NO_LISTING 69 struct list_info_struct *line; 70 #endif 71 72 /* A serial number for a sequence of frags having at most one alignment 73 or org frag, and that at the tail of the sequence. */ 74 unsigned int region:16; 75 76 /* Flipped each relax pass so we can easily determine whether 77 fr_address has been adjusted. */ 78 unsigned int relax_marker:1; 79 80 /* Used to ensure that all insns are emitted on proper address 81 boundaries. */ 82 unsigned int has_code:1; 83 unsigned int insn_addr:6; 84 85 /* What state is my tail in? */ 86 relax_stateT fr_type; 87 relax_substateT fr_subtype; 88 89 #ifdef USING_CGEN 90 /* Don't include this unless using CGEN to keep frag size down. */ 91 struct { 92 /* CGEN_INSN entry for this instruction. */ 93 const struct cgen_insn *insn; 94 /* Index into operand table. */ 95 int opindex; 96 /* Target specific data, usually reloc number. */ 97 int opinfo; 98 } fr_cgen; 99 #endif 100 101 #ifdef TC_FRAG_TYPE 102 TC_FRAG_TYPE tc_frag_data; 103 #endif 104 #ifdef OBJ_FRAG_TYPE 105 OBJ_FRAG_TYPE obj_frag_data; 106 #endif 107 108 /* Data begins here. */ 109 char fr_literal[1]; 110 }; 111 112 #define SIZEOF_STRUCT_FRAG \ 113 ((char *) zero_address_frag.fr_literal - (char *) &zero_address_frag) 114 /* We want to say fr_literal[0] above. */ 115 116 /* Current frag we are building. This frag is incomplete. It is, 117 however, included in frchain_now. The fr_fix field is bogus; 118 instead, use frag_now_fix (). */ 119 COMMON fragS *frag_now; 120 extern addressT frag_now_fix (void); 121 extern addressT frag_now_fix_octets (void); 122 123 /* For foreign-segment symbol fixups. */ 124 COMMON fragS zero_address_frag; 125 COMMON fragS predefined_address_frag; 126 127 extern void frag_append_1_char (int); 128 #define FRAG_APPEND_1_CHAR(X) frag_append_1_char (X) 129 130 void frag_init (void); 131 fragS *frag_alloc (struct obstack *); 132 void frag_grow (unsigned int nchars); 133 char *frag_more (int nchars); 134 void frag_align (int alignment, int fill_character, int max); 135 void frag_align_pattern (int alignment, const char *fill_pattern, 136 int n_fill, int max); 137 void frag_align_code (int alignment, int max); 138 void frag_new (int old_frags_var_max_size); 139 void frag_wane (fragS * fragP); 140 int frag_room (void); 141 142 char *frag_variant (relax_stateT type, 143 int max_chars, 144 int var, 145 relax_substateT subtype, 146 symbolS * symbol, 147 offsetT offset, 148 char *opcode); 149 150 char *frag_var (relax_stateT type, 151 int max_chars, 152 int var, 153 relax_substateT subtype, 154 symbolS * symbol, 155 offsetT offset, 156 char *opcode); 157 158 bfd_boolean frag_offset_fixed_p (const fragS *, const fragS *, offsetT *); 159 160 #endif /* FRAGS_H */ 161