Copyright 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
2002, 2003, 2007 Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
GAS 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, or (at your option)
any later version.
GAS 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 GAS; see the file COPYING. If not, write to the Free
Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
02110-1301, USA. */
* By popular demand, we define a struct to represent an expression.
* This will no doubt mutate as expressions become baroque.
*
* Currently, we support expressions like "foo OP bar + 42". In other
* words we permit a (possibly undefined) symbol, a (possibly
* undefined) symbol and the operation used to combine the symbols,
* and an (absolute) augend. RMS says this is so we can have 1-pass
* assembly for any compiler emissions, and a 'case' statement might
* emit 'undefined1 - undefined2'.
*
* The type of an expression used to be stored as a segment. That got
* confusing because it overloaded the concept of a segment. I added
* an operator field, instead.
*/
used while parsing an expression.
NOTE: This enumeration must match the op_rank array in expr.c. */
typedef enum {
O_illegal,
O_absent,
O_constant,
O_symbol,
O_symbol_rva,
O_register,
generic_floating_point_number. Otherwise the value is in
generic_bignum, and X_add_number is the number of LITTLENUMs in
the value. */
O_big,
O_uminus,
O_bit_not,
O_logical_not,
O_multiply,
O_divide,
O_modulus,
O_left_shift,
O_right_shift,
O_bit_inclusive_or,
O_bit_or_not,
O_bit_exclusive_or,
O_bit_and,
O_add,
O_subtract,
O_eq,
O_ne,
O_lt,
O_le,
O_ge,
O_gt,
O_logical_and,
O_logical_or,
O_index,
O_md1, O_md2, O_md3, O_md4, O_md5, O_md6, O_md7, O_md8,
O_md9, O_md10, O_md11, O_md12, O_md13, O_md14, O_md15, O_md16,
O_md17, O_md18, O_md19, O_md20, O_md21, O_md22, O_md23, O_md24,
O_md25, O_md26, O_md27, O_md28, O_md29, O_md30, O_md31, O_md32,
O_max
} operatorT;
typedef struct expressionS {
symbolS *X_add_symbol;
symbolS *X_op_symbol;
offsetT X_add_number;
compiler can handle a bitfield of enum type. FIXME: We could
check this using autoconf. */
#ifdef __GNUC__
operatorT X_op : 8;
#else
unsigned char X_op;
#endif
only valid for O_constant expressions. It is only used when an
O_constant must be extended into a bignum (i.e., it is not used
when performing arithmetic on these values).
FIXME: This field is not set very reliably. */
unsigned int X_unsigned : 1;
unsigned short X_md;
} expressionS;
enum expr_mode
{
expr_evaluate,
expr_normal,
expr_defer
};
#define expression(result) expr (0, result, expr_normal)
#define expression_and_evaluate(result) expr (0, result, expr_evaluate)
#define deferred_expression(result) expr (0, result, expr_defer)
data may be clobbered whenever expr() is called. */
extern FLONUM_TYPE generic_floating_point_number;
extern LITTLENUM_TYPE generic_bignum[];
#define SIZE_OF_LARGE_NUMBER (20)
typedef char operator_rankT;
extern char get_symbol_end (void);
extern void expr_begin (void);
extern void expr_set_precedence (void);
extern segT expr (int, expressionS *, enum expr_mode);
extern unsigned int get_single_number (void);
extern symbolS *make_expr_symbol (expressionS * expressionP);
extern int expr_symbol_where (symbolS *, char **, unsigned int *);
extern symbolS *expr_build_uconstant (offsetT);
extern symbolS *expr_build_dot (void);
int resolve_expression (expressionS *);
