gas/write.h

   1 /* write.h
   2    Copyright (C) 1987-2016 Free Software Foundation, Inc.
   3
   4    This file is part of GAS, the GNU Assembler.
   5
   6    GAS 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, or (at your option)
   9    any later version.
  10
  11    GAS 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 GAS; see the file COPYING.  If not, write to the Free
  18    Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
  19    02110-1301, USA.  */
  20
  21 #ifndef __write_h__
  22 #define __write_h__
  23
  24 /* This is the name of a fake symbol which will never appear in the
  25    assembler output.  S_IS_LOCAL detects it because of the \001.  */
  26 #ifndef FAKE_LABEL_NAME
  27 #define FAKE_LABEL_NAME "L0\001"
  28 #endif
  29
  30 #include "bit_fix.h"
  31
  32 /*
  33  * FixSs may be built up in any order.
  34  */
  35
  36 struct fix
  37 {
  38   /* These small fields are grouped together for compactness of
  39      this structure, and efficiency of access on some architectures.  */
  40
  41   /* Is this a pc-relative relocation?  */
  42   unsigned fx_pcrel : 1;
  43
  44   /* Is this value an immediate displacement?  */
  45   /* Only used on ns32k; merge it into TC_FIX_TYPE sometime.  */
  46   unsigned fx_im_disp : 2;
  47
  48   /* Some bits for the CPU specific code.  */
  49   unsigned fx_tcbit : 1;
  50   unsigned fx_tcbit2 : 1;
  51
  52   /* Has this relocation already been applied?  */
  53   unsigned fx_done : 1;
  54
  55   /* Suppress overflow complaints on large addends.  This is used
  56      in the PowerPC ELF config to allow large addends on the
  57      BFD_RELOC_{LO16,HI16,HI16_S} relocations.
  58
  59      @@ Can this be determined from BFD?  */
  60   unsigned fx_no_overflow : 1;
  61
  62   /* The value is signed when checking for overflow.  */
  63   unsigned fx_signed : 1;
  64
  65   /* pc-relative offset adjust (only used by some CPU specific code) */
  66   signed char fx_pcrel_adjust;
  67
  68   /* How many bytes are involved? */
  69   unsigned char fx_size;
  70
  71   /* Which frag does this fix apply to?  */
  72   fragS *fx_frag;
  73
  74   /* Where is the first byte to fix up?  */
  75   long fx_where;
  76
  77   /* NULL or Symbol whose value we add in.  */
  78   symbolS *fx_addsy;
  79
  80   /* NULL or Symbol whose value we subtract.  */
  81   symbolS *fx_subsy;
  82
  83   /* Absolute number we add in.  */
  84   valueT fx_offset;
  85
  86   /* The value of dot when the fixup expression was parsed.  */
  87   addressT fx_dot_value;
  88
  89   /* The frag fx_dot_value is based on.  */
  90   fragS *fx_dot_frag;
  91
  92   /* Next fixS in linked list, or NULL.  */
  93   struct fix *fx_next;
  94
  95   /* If NULL, no bitfix's to do.  */
  96   /* Only i960-coff and ns32k use this, and i960-coff stores an
  97      integer.  This can probably be folded into tc_fix_data, below.
  98      @@ Alpha also uses it, but only to disable certain relocation
  99      processing.  */
 100   bit_fixS *fx_bit_fixP;
 101
 102   bfd_reloc_code_real_type fx_r_type;
 103
 104   /* This field is sort of misnamed.  It appears to be a sort of random
 105      scratch field, for use by the back ends.  The main gas code doesn't
 106      do anything but initialize it to zero.  The use of it does need to
 107      be coordinated between the cpu and format files, though.  E.g., some
 108      coff targets pass the `addend' field from the cpu file via this
 109      field.  I don't know why the `fx_offset' field above can't be used
 110      for that; investigate later and document. KR  */
 111   valueT fx_addnumber;
 112
 113   /* The location of the instruction which created the reloc, used
 114      in error messages.  */
 115   const char *fx_file;
 116   unsigned fx_line;
 117
 118 #ifdef USING_CGEN
 119   struct {
 120     /* CGEN_INSN entry for this instruction.  */
 121     const struct cgen_insn *insn;
 122     /* Target specific data, usually reloc number.  */
 123     int opinfo;
 124     /* Which ifield this fixup applies to. */
 125     struct cgen_maybe_multi_ifield * field;
 126     /* is this field is the MSB field in a set? */
 127     int msb_field_p;
 128   } fx_cgen;
 129 #endif
 130
 131 #ifdef TC_FIX_TYPE
 132   /* Location where a backend can attach additional data
 133      needed to perform fixups.  */
 134   TC_FIX_TYPE tc_fix_data;
 135 #endif
 136 };
 137
 138 typedef struct fix fixS;
 139
 140 struct reloc_list
 141 {
 142   struct reloc_list *next;
 143   union
 144   {
 145     struct
 146     {
 147       symbolS *offset_sym;
 148       reloc_howto_type *howto;
 149       symbolS *sym;
 150       bfd_vma addend;
 151     } a;
 152     struct
 153     {
 154       asection *sec;
 155       asymbol *s;
 156       arelent r;
 157     } b;
 158   } u;
 159   const char *file;
 160   unsigned int line;
 161 };
 162
 163 extern int finalize_syms;
 164 extern symbolS *abs_section_sym;
 165 extern addressT dot_value;
 166 extern fragS *dot_frag;
 167 extern struct reloc_list* reloc_list;
 168
 169 extern void append (char **, char *, unsigned long);
 170 extern void record_alignment (segT, unsigned);
 171 extern int get_recorded_alignment (segT);
 172 extern void write_object_file (void);
 173 extern long relax_frag (segT, fragS *, long);
 174 extern int relax_segment (struct frag *, segT, int);
 175 extern void number_to_chars_littleendian (char *, valueT, int);
 176 extern void number_to_chars_bigendian (char *, valueT, int);
 177 extern fixS *fix_new
 178   (fragS * frag, int where, int size, symbolS * add_symbol,
 179    offsetT offset, int pcrel, bfd_reloc_code_real_type r_type);
 180 extern fixS *fix_at_start
 181   (fragS * frag, int size, symbolS * add_symbol,
 182    offsetT offset, int pcrel, bfd_reloc_code_real_type r_type);
 183 extern fixS *fix_new_exp
 184   (fragS * frag, int where, int size, expressionS *exp, int pcrel,
 185    bfd_reloc_code_real_type r_type);
 186 extern void write_print_statistics (FILE *);
 187
 188 #endif /* __write_h__ */