gold/yyscript.y

   1 /* yyscript.y -- linker script grammer for gold.  */
   2
   3 /* Copyright 2006, 2007 Free Software Foundation, Inc.
   4    Written by Ian Lance Taylor <iant@google.com>.
   5
   6    This file is part of gold.
   7
   8    This program 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 of the License, or
  11    (at your option) any later version.
  12
  13    This program 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 this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21    MA 02110-1301, USA.  */
  22
  23 /* This is a bison grammar to parse a subset of the original GNU ld
  24    linker script language.  */
  25
  26 %{
  27
  28 #include "config.h"
  29
  30 #include <stddef.h>
  31 #include <stdint.h>
  32
  33 #include "script-c.h"
  34
  35 %}
  36
  37 /* We need to use a pure parser because we might be multi-threaded.
  38    We pass some arguments through the parser to the lexer.  */
  39
  40 %pure-parser
  41
  42 %parse-param {void* closure}
  43 %lex-param {void* closure}
  44
  45 /* Since we require bison anyhow, we take advantage of it.  */
  46
  47 %error-verbose
  48
  49 /* The values associated with tokens.  */
  50
  51 %union {
  52   const char* string;
  53   int64_t integer;
  54 }
  55
  56 /* Operators, including a precedence table for expressions.  */
  57
  58 %right PLUSEQ MINUSEQ MULTEQ DIVEQ '=' LSHIFTEQ RSHIFTEQ ANDEQ OREQ
  59 %right '?' ':'
  60 %left OROR
  61 %left ANDAND
  62 %left '|'
  63 %left '^'
  64 %left '&'
  65 %left EQ NE
  66 %left '<' '>' LE GE
  67 %left LSHIFT RSHIFT
  68 %left '+' '-'
  69 %left '*' '/' '%'
  70
  71 /* Constants.  */
  72
  73 %token <string> STRING
  74 %token <integer> INTEGER
  75
  76 /* Keywords.  This list is taken from ldgram.y and ldlex.l in the old
  77    GNU linker, with the keywords which only appear in MRI mode
  78    removed.  Not all these keywords are actually used in this grammar.
  79    In most cases the keyword is recognized as the token name in upper
  80    case.  The comments indicate where this is not the case.  */
  81
  82 %token ABSOLUTE
  83 %token ADDR
  84 %token ALIGN_K          /* ALIGN */
  85 %token ASSERT_K         /* ASSERT */
  86 %token AS_NEEDED
  87 %token AT
  88 %token BIND
  89 %token BLOCK
  90 %token BYTE
  91 %token CONSTANT
  92 %token CONSTRUCTORS
  93 %token COPY
  94 %token CREATE_OBJECT_SYMBOLS
  95 %token DATA_SEGMENT_ALIGN
  96 %token DATA_SEGMENT_END
  97 %token DATA_SEGMENT_RELRO_END
  98 %token DEFINED
  99 %token DSECT
 100 %token ENTRY
 101 %token EXCLUDE_FILE
 102 %token EXTERN
 103 %token FILL
 104 %token FLOAT
 105 %token FORCE_COMMON_ALLOCATION
 106 %token GLOBAL           /* global */
 107 %token GROUP
 108 %token HLL
 109 %token INCLUDE
 110 %token INFO
 111 %token INHIBIT_COMMON_ALLOCATION
 112 %token INPUT
 113 %token KEEP
 114 %token LENGTH           /* LENGTH, l, len */
 115 %token LOADADDR
 116 %token LOCAL            /* local */
 117 %token LONG
 118 %token MAP
 119 %token MAX_K            /* MAX */
 120 %token MEMORY
 121 %token MIN_K            /* MIN */
 122 %token NEXT
 123 %token NOCROSSREFS
 124 %token NOFLOAT
 125 %token NOLOAD
 126 %token ONLY_IF_RO
 127 %token ONLY_IF_RW
 128 %token ORIGIN           /* ORIGIN, o, org */
 129 %token OUTPUT
 130 %token OUTPUT_ARCH
 131 %token OUTPUT_FORMAT
 132 %token OVERLAY
 133 %token PHDRS
 134 %token PROVIDE
 135 %token PROVIDE_HIDDEN
 136 %token QUAD
 137 %token SEARCH_DIR
 138 %token SECTIONS
 139 %token SEGMENT_START
 140 %token SHORT
 141 %token SIZEOF
 142 %token SIZEOF_HEADERS   /* SIZEOF_HEADERS, sizeof_headers */
 143 %token SORT_BY_ALIGNMENT
 144 %token SORT_BY_NAME
 145 %token SPECIAL
 146 %token SQUAD
 147 %token STARTUP
 148 %token SUBALIGN
 149 %token SYSLIB
 150 %token TARGET_K         /* TARGET */
 151 %token TRUNCATE
 152 %token VERSIONK         /* VERSION */
 153
 154 /* Keywords, part 2.  These are keywords that are unique to gold,
 155    and not present in the old GNU linker.  As before, unless the
 156    comments say otherwise, the keyword is recognized as the token
 157    name in upper case. */
 158
 159 %token OPTION
 160
 161 %%
 162
 163 /* A file contains a list of commands.  */
 164 file_list:
 165           file_list file_cmd
 166         | /* empty */
 167         ;
 168
 169 /* A command which may appear at top level of a linker script.  */
 170 file_cmd:
 171           OUTPUT_FORMAT '(' STRING ')'
 172         | GROUP
 173             { script_start_group(closure); }
 174           '(' input_list ')'
 175             { script_end_group(closure); }
 176         | OPTION '(' STRING ')'
 177             { script_parse_option(closure, $3); }
 178         | file_or_sections_cmd
 179         ;
 180
 181 /* A list of input file names.  */
 182 input_list:
 183           input_list_element
 184         | input_list opt_comma input_list_element
 185         ;
 186
 187 /* An input file name.  */
 188 input_list_element:
 189           STRING
 190             { script_add_file(closure, $1); }
 191         | AS_NEEDED
 192             { script_start_as_needed(closure); }
 193           '(' input_list ')'
 194             { script_end_as_needed(closure); }
 195         ;
 196
 197 /* A command which may appear at the top level of a linker script, or
 198    within a SECTIONS block.  */
 199 file_or_sections_cmd:
 200           ENTRY '(' STRING ')'
 201             { script_set_entry(closure, $3); }
 202         ;
 203
 204 /* An optional comma.  */
 205 opt_comma:
 206           ','
 207         | /* empty */
 208         ;
 209
 210 %%