ld/ldexp.h

   1 /* ldexp.h -
   2    Copyright 1991, 1992, 1993, 1994, 1995, 1998, 1999, 2000, 2001, 2002,
   3    2003, 2004, 2005, 2007, 2011, 2012 Free Software Foundation, Inc.
   4
   5    This file is part of the GNU Binutils.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  20    MA 02110-1301, USA.  */
  21
  22 #ifndef LDEXP_H
  23 #define LDEXP_H
  24
  25 /* The result of an expression tree */
  26 typedef struct {
  27   bfd_vma value;
  28   char *str;
  29   asection *section;
  30   bfd_boolean valid_p;
  31 } etree_value_type;
  32
  33 enum node_tree_enum {
  34   etree_binary,
  35   etree_trinary,
  36   etree_unary,
  37   etree_name,
  38   etree_assign,
  39   etree_provide,
  40   etree_provided,
  41   etree_value,
  42   etree_assert,
  43   etree_rel
  44 };
  45
  46 typedef struct {
  47   int node_code;
  48   unsigned int lineno;
  49   const char *filename;
  50   enum node_tree_enum node_class;
  51 } node_type;
  52
  53 typedef union etree_union {
  54   node_type type;
  55   struct {
  56     node_type type;
  57     union etree_union *lhs;
  58     union etree_union *rhs;
  59   } binary;
  60   struct {
  61     node_type type;
  62     union etree_union *cond;
  63     union etree_union *lhs;
  64     union etree_union *rhs;
  65   } trinary;
  66   struct {
  67     node_type type;
  68     const char *dst;
  69     union etree_union *src;
  70     bfd_boolean defsym;
  71     bfd_boolean hidden;
  72   } assign;
  73   struct {
  74     node_type type;
  75     union etree_union *child;
  76   } unary;
  77   struct {
  78     node_type type;
  79     const char *name;
  80   } name;
  81   struct {
  82     node_type type;
  83     bfd_vma value;
  84     char *str;
  85   } value;
  86   struct {
  87     node_type type;
  88     asection *section;
  89     bfd_vma value;
  90   } rel;
  91   struct {
  92     node_type type;
  93     union etree_union *child;
  94     const char *message;
  95   } assert_s;
  96 } etree_type;
  97
  98 /* Expression evaluation control.  */
  99 typedef enum
 100 {
 101   /* Parsing linker script.  Will only return "valid" for expressions
 102      that evaluate to a constant.  */
 103   lang_first_phase_enum,
 104   /* Prior to section sizing.  */
 105   lang_mark_phase_enum,
 106   /* During section sizing.  */
 107   lang_allocating_phase_enum,
 108   /* During assignment of symbol values when relaxation in progress.  */
 109   lang_assigning_phase_enum,
 110   /* Final assignment of symbol values.  */
 111   lang_final_phase_enum
 112 } lang_phase_type;
 113
 114 union lang_statement_union;
 115
 116 enum phase_enum {
 117   /* We step through the first four states here as we see the
 118      associated linker script tokens.  */
 119   exp_dataseg_none,
 120   exp_dataseg_align_seen,
 121   exp_dataseg_relro_seen,
 122   exp_dataseg_end_seen,
 123   /* The last three states are final, and affect the value returned
 124      by DATA_SEGMENT_ALIGN.  */
 125   exp_dataseg_relro_adjust,
 126   exp_dataseg_adjust,
 127   exp_dataseg_done
 128 };
 129
 130 enum relro_enum {
 131   exp_dataseg_relro_none,
 132   exp_dataseg_relro_start,
 133   exp_dataseg_relro_end,
 134 };
 135
 136 struct ldexp_control {
 137   /* Modify expression evaluation depending on this.  */
 138   lang_phase_type phase;
 139
 140   /* Principally used for diagnostics.  */
 141   bfd_boolean assigning_to_dot;
 142   /* If evaluating an assignment, the destination.  Cleared if an
 143      etree_name NAME matches this, to signal a self-assignment.
 144      Note that an etree_name DEFINED does not clear this field, nor
 145      does the false branch of a trinary expression.  */
 146   const char *assign_name;
 147
 148   /* Working results.  */
 149   etree_value_type result;
 150   bfd_vma dot;
 151
 152   /* Current dot and section passed to ldexp folder.  */
 153   bfd_vma *dotp;
 154   asection *section;
 155
 156   /* State machine and results for DATASEG.  */
 157   struct {
 158     enum phase_enum phase;
 159
 160     bfd_vma base, min_base, relro_end, end, pagesize, maxpagesize;
 161
 162     enum relro_enum relro;
 163
 164     union lang_statement_union *relro_start_stat;
 165     union lang_statement_union *relro_end_stat;
 166   } dataseg;
 167 };
 168
 169 extern struct ldexp_control expld;
 170
 171 /* A maps from a segment name to a base address.  */
 172 typedef struct segment_struct {
 173   /* The next segment in the linked list.  */
 174   struct segment_struct *next;
 175   /* The name of the sgement.  */
 176   const char *name;
 177   /* The base address for the segment.  */
 178   bfd_vma value;
 179   /* True if a SEGMENT_START directive corresponding to this segment
 180      has been seen.  */
 181   bfd_boolean used;
 182 } segment_type;
 183
 184 /* The segments specified by the user on the command-line.  */
 185 extern segment_type *segments;
 186
 187 typedef struct _fill_type fill_type;
 188
 189 etree_type *exp_intop
 190   (bfd_vma);
 191 etree_type *exp_bigintop
 192   (bfd_vma, char *);
 193 etree_type *exp_relop
 194   (asection *, bfd_vma);
 195 void exp_fold_tree
 196   (etree_type *, asection *, bfd_vma *);
 197 void exp_fold_tree_no_dot
 198   (etree_type *);
 199 etree_type *exp_binop
 200   (int, etree_type *, etree_type *);
 201 etree_type *exp_trinop
 202   (int,etree_type *, etree_type *, etree_type *);
 203 etree_type *exp_unop
 204   (int, etree_type *);
 205 etree_type *exp_nameop
 206   (int, const char *);
 207 etree_type *exp_assign
 208   (const char *, etree_type *, bfd_boolean);
 209 etree_type *exp_defsym
 210   (const char *, etree_type *);
 211 etree_type *exp_provide
 212   (const char *, etree_type *, bfd_boolean);
 213 etree_type *exp_assert
 214   (etree_type *, const char *);
 215 void exp_print_tree
 216   (etree_type *);
 217 bfd_vma exp_get_vma
 218   (etree_type *, bfd_vma, char *);
 219 int exp_get_value_int
 220   (etree_type *, int, char *);
 221 fill_type *exp_get_fill
 222   (etree_type *, fill_type *, char *);
 223 bfd_vma exp_get_abs_int
 224   (etree_type *, int, char *);
 225
 226 #endif