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|
/* yyscript.y -- linker script grammer for gold. */
/* Copyright 2006, 2007 Free Software Foundation, Inc.
Written by Ian Lance Taylor <iant@google.com>.
This file is part of gold.
This program 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 3 of the License, or
(at your option) any later version.
This program 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 this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
/* This is a bison grammar to parse a subset of the original GNU ld
linker script language. */
%{
#include "config.h"
#include <stddef.h>
#include <stdint.h>
#include "script-c.h"
%}
/* We need to use a pure parser because we might be multi-threaded.
We pass some arguments through the parser to the lexer. */
%pure-parser
%parse-param {void* closure}
%lex-param {void* closure}
/* Since we require bison anyhow, we take advantage of it. */
%error-verbose
/* The values associated with tokens. */
%union {
const char* string;
int64_t integer;
}
/* Operators, including a precedence table for expressions. */
%right PLUSEQ MINUSEQ MULTEQ DIVEQ '=' LSHIFTEQ RSHIFTEQ ANDEQ OREQ
%right '?' ':'
%left OROR
%left ANDAND
%left '|'
%left '^'
%left '&'
%left EQ NE
%left '<' '>' LE GE
%left LSHIFT RSHIFT
%left '+' '-'
%left '*' '/' '%'
/* Constants. */
%token <string> STRING
%token <integer> INTEGER
/* Keywords. This list is taken from ldgram.y and ldlex.l in the old
GNU linker, with the keywords which only appear in MRI mode
removed. Not all these keywords are actually used in this grammar.
In most cases the keyword is recognized as the token name in upper
case. The comments indicate where this is not the case. */
%token ABSOLUTE
%token ADDR
%token ALIGN_K /* ALIGN */
%token ASSERT_K /* ASSERT */
%token AS_NEEDED
%token AT
%token BIND
%token BLOCK
%token BYTE
%token CONSTANT
%token CONSTRUCTORS
%token COPY
%token CREATE_OBJECT_SYMBOLS
%token DATA_SEGMENT_ALIGN
%token DATA_SEGMENT_END
%token DATA_SEGMENT_RELRO_END
%token DEFINED
%token DSECT
%token ENTRY
%token EXCLUDE_FILE
%token EXTERN
%token FILL
%token FLOAT
%token FORCE_COMMON_ALLOCATION
%token GLOBAL /* global */
%token GROUP
%token HLL
%token INCLUDE
%token INFO
%token INHIBIT_COMMON_ALLOCATION
%token INPUT
%token KEEP
%token LENGTH /* LENGTH, l, len */
%token LOADADDR
%token LOCAL /* local */
%token LONG
%token MAP
%token MAX_K /* MAX */
%token MEMORY
%token MIN_K /* MIN */
%token NEXT
%token NOCROSSREFS
%token NOFLOAT
%token NOLOAD
%token ONLY_IF_RO
%token ONLY_IF_RW
%token ORIGIN /* ORIGIN, o, org */
%token OUTPUT
%token OUTPUT_ARCH
%token OUTPUT_FORMAT
%token OVERLAY
%token PHDRS
%token PROVIDE
%token PROVIDE_HIDDEN
%token QUAD
%token SEARCH_DIR
%token SECTIONS
%token SEGMENT_START
%token SHORT
%token SIZEOF
%token SIZEOF_HEADERS /* SIZEOF_HEADERS, sizeof_headers */
%token SORT_BY_ALIGNMENT
%token SORT_BY_NAME
%token SPECIAL
%token SQUAD
%token STARTUP
%token SUBALIGN
%token SYSLIB
%token TARGET_K /* TARGET */
%token TRUNCATE
%token VERSIONK /* VERSION */
/* Keywords, part 2. These are keywords that are unique to gold,
and not present in the old GNU linker. As before, unless the
comments say otherwise, the keyword is recognized as the token
name in upper case. */
%token OPTION
%%
/* A file contains a list of commands. */
file_list:
file_list file_cmd
| /* empty */
;
/* A command which may appear at top level of a linker script. */
file_cmd:
GROUP
{ script_start_group(closure); }
'(' input_list ')'
{ script_end_group(closure); }
| OPTION '(' STRING ')'
{ script_parse_option(closure, $3); }
| file_or_sections_cmd
| ignore_cmd
;
/* Top level commands which we ignore. The GNU linker uses these to
select the output format, but we don't offer a choice. Ignoring
these is more-or-less OK since most scripts simply explicitly
choose the default. */
ignore_cmd:
OUTPUT_FORMAT '(' STRING ')'
| OUTPUT_FORMAT '(' STRING ',' STRING ',' STRING ')'
| OUTPUT_ARCH '(' STRING ')'
;
/* A list of input file names. */
input_list:
input_list_element
| input_list opt_comma input_list_element
;
/* An input file name. */
input_list_element:
STRING
{ script_add_file(closure, $1); }
| AS_NEEDED
{ script_start_as_needed(closure); }
'(' input_list ')'
{ script_end_as_needed(closure); }
;
/* A command which may appear at the top level of a linker script, or
within a SECTIONS block. */
file_or_sections_cmd:
ENTRY '(' STRING ')'
{ script_set_entry(closure, $3); }
;
/* An optional comma. */
opt_comma:
','
| /* empty */
;
%%
|
