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Diffstat (limited to 'binutils-2.25/gas/expr.h')
| -rw-r--r-- | binutils-2.25/gas/expr.h | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/binutils-2.25/gas/expr.h b/binutils-2.25/gas/expr.h new file mode 100644 index 00000000..438ac0dc --- /dev/null +++ b/binutils-2.25/gas/expr.h @@ -0,0 +1,189 @@ +/* expr.h -> header file for expr.c + Copyright 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, + 2002, 2003, 2005, 2007, 2009 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. + */ + +/* This is the type of an expression. The operator types are also + used while parsing an expression. + + NOTE: This enumeration must match the op_rank array in expr.c. */ + +typedef enum { + /* An illegal expression. */ + O_illegal, + /* A nonexistent expression. */ + O_absent, + /* X_add_number (a constant expression). */ + O_constant, + /* X_add_symbol + X_add_number. */ + O_symbol, + /* X_add_symbol + X_add_number - the base address of the image. */ + O_symbol_rva, + /* A register (X_add_number is register number). */ + O_register, + /* A big value. If X_add_number is negative or 0, the value is in + 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, + /* (- X_add_symbol) + X_add_number. */ + O_uminus, + /* (~ X_add_symbol) + X_add_number. */ + O_bit_not, + /* (! X_add_symbol) + X_add_number. */ + O_logical_not, + /* (X_add_symbol * X_op_symbol) + X_add_number. */ + O_multiply, + /* (X_add_symbol / X_op_symbol) + X_add_number. */ + O_divide, + /* (X_add_symbol % X_op_symbol) + X_add_number. */ + O_modulus, + /* (X_add_symbol << X_op_symbol) + X_add_number. */ + O_left_shift, + /* (X_add_symbol >> X_op_symbol) + X_add_number. */ + O_right_shift, + /* (X_add_symbol | X_op_symbol) + X_add_number. */ + O_bit_inclusive_or, + /* (X_add_symbol |~ X_op_symbol) + X_add_number. */ + O_bit_or_not, + /* (X_add_symbol ^ X_op_symbol) + X_add_number. */ + O_bit_exclusive_or, + /* (X_add_symbol & X_op_symbol) + X_add_number. */ + O_bit_and, + /* (X_add_symbol + X_op_symbol) + X_add_number. */ + O_add, + /* (X_add_symbol - X_op_symbol) + X_add_number. */ + O_subtract, + /* (X_add_symbol == X_op_symbol) + X_add_number. */ + O_eq, + /* (X_add_symbol != X_op_symbol) + X_add_number. */ + O_ne, + /* (X_add_symbol < X_op_symbol) + X_add_number. */ + O_lt, + /* (X_add_symbol <= X_op_symbol) + X_add_number. */ + O_le, + /* (X_add_symbol >= X_op_symbol) + X_add_number. */ + O_ge, + /* (X_add_symbol > X_op_symbol) + X_add_number. */ + O_gt, + /* (X_add_symbol && X_op_symbol) + X_add_number. */ + O_logical_and, + /* (X_add_symbol || X_op_symbol) + X_add_number. */ + O_logical_or, + /* X_op_symbol [ X_add_symbol ] */ + O_index, + /* machine dependent operators */ + 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, + /* this must be the largest value */ + O_max +} operatorT; + +typedef struct expressionS { + /* The main symbol. */ + symbolS *X_add_symbol; + /* The second symbol, if needed. */ + symbolS *X_op_symbol; + /* A number to add. */ + offsetT X_add_number; + + /* The type of the expression. We can't assume that an arbitrary + 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 + + /* Non-zero if X_add_number should be regarded as unsigned. This is + 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; + /* This is used to implement "word size + 1 bit" arithmetic, so that e.g. + expressions used with .sleb128 directives can use the full range available + for an unsigned word, but can also properly represent all values of a + signed word. */ + unsigned int X_extrabit : 1; + + /* 7 additional bits can be defined if needed. */ + + /* Machine dependent field */ + unsigned short X_md; +} expressionS; + +enum expr_mode +{ + expr_evaluate, + expr_normal, + expr_defer +}; + +/* "result" should be type (expressionS *). */ +#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) + +/* If an expression is O_big, look here for its value. These common + data may be clobbered whenever expr() is called. */ +/* Flonums returned here. Big enough to hold most precise flonum. */ +extern FLONUM_TYPE generic_floating_point_number; +/* Bignums returned here. */ +extern LITTLENUM_TYPE generic_bignum[]; +/* Number of littlenums in above. */ +#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 void expr_set_rank (operatorT, operator_rankT); +extern void add_to_result (expressionS *, offsetT, int); +extern void subtract_from_result (expressionS *, offsetT, int); +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 void current_location (expressionS *); + +extern symbolS *expr_build_uconstant (offsetT); +extern symbolS *expr_build_dot (void); + +int resolve_expression (expressionS *); |