1 /* expr.c -operands, expressions-
2 Copyright (C) 1987, 1990, 1991, 1992 Free Software Foundation, Inc.
4 This file is part of GAS, the GNU Assembler.
6 GAS is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GAS is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GAS; see the file COPYING. If not, write to
18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
21 * This is really a branch office of as-read.c. I split it out to clearly
22 * distinguish the world of expressions from the world of statements.
23 * (It also gives smaller files to re-compile.)
24 * Here, "operand"s are of expressions, not instructions.
35 static void clean_up_expression (expressionS
* expressionP
);
37 static void clean_up_expression (); /* Internal. */
38 #endif /* not __STDC__ */
39 extern const char EXP_CHARS
[]; /* JF hide MD floating pt stuff all the same place */
40 extern const char FLT_CHARS
[];
43 * Build any floating-point literal here.
44 * Also build any bignum literal here.
47 /* LITTLENUM_TYPE generic_buffer [6]; *//* JF this is a hack */
48 /* Seems atof_machine can backscan through generic_bignum and hit whatever
49 happens to be loaded before it in memory. And its way too complicated
50 for me to fix right. Thus a hack. JF: Just make generic_bignum bigger,
51 and never write into the early words, thus they'll always be zero.
52 I hate Dean's floating-point code. Bleh.
54 LITTLENUM_TYPE generic_bignum
[SIZE_OF_LARGE_NUMBER
+ 6];
55 FLONUM_TYPE generic_floating_point_number
=
57 &generic_bignum
[6], /* low (JF: Was 0) */
58 &generic_bignum
[SIZE_OF_LARGE_NUMBER
+ 6 - 1], /* high JF: (added +6) */
63 /* If nonzero, we've been asked to assemble nan, +inf or -inf */
64 int generic_floating_point_magic
;
66 floating_constant (expressionP
)
67 expressionS
*expressionP
;
69 /* input_line_pointer->*/
70 /* floating-point constant. */
73 error_code
= atof_generic
74 (&input_line_pointer
, ".", EXP_CHARS
,
75 &generic_floating_point_number
);
79 if (error_code
== ERROR_EXPONENT_OVERFLOW
)
81 as_bad ("bad floating-point constant: exponent overflow, probably assembling junk");
85 as_bad ("bad floating-point constant: unknown error code=%d.", error_code
);
88 expressionP
->X_seg
= SEG_BIG
;
89 /* input_line_pointer->just after constant, */
90 /* which may point to whitespace. */
91 expressionP
->X_add_number
= -1;
96 integer_constant (radix
, expressionP
)
98 expressionS
*expressionP
;
100 register char *digit_2
; /*->2nd digit of number. */
103 register valueT number
; /* offset or (absolute) value */
104 register short int digit
; /* value of next digit in current radix */
105 register short int maxdig
= 0;/* highest permitted digit value. */
106 register int too_many_digits
= 0; /* if we see >= this number of */
107 register char *name
; /* points to name of symbol */
108 register symbolS
*symbolP
; /* points to symbol */
110 int small
; /* true if fits in 32 bits. */
111 extern char hex_value
[]; /* in hex_value.c */
113 /* may be bignum, or may fit in 32 bits. */
115 * most numbers fit into 32 bits, and we want this case to be fast.
116 * so we pretend it will fit into 32 bits. if, after making up a 32
117 * bit number, we realise that we have scanned more digits than
118 * comfortably fit into 32 bits, we re-scan the digits coding
119 * them into a bignum. for decimal and octal numbers we are conservative: some
120 * numbers may be assumed bignums when in fact they do fit into 32 bits.
121 * numbers of any radix can have excess leading zeros: we strive
122 * to recognise this and cast them back into 32 bits.
123 * we must check that the bignum really is more than 32
124 * bits, and change it back to a 32-bit number if it fits.
125 * the number we are looking for is expected to be positive, but
126 * if it fits into 32 bits as an unsigned number, we let it be a 32-bit
127 * number. the cavalier approach is for speed in ordinary cases.
135 too_many_digits
= 33;
139 too_many_digits
= 11;
149 too_many_digits
= 11;
151 c
= *input_line_pointer
;
152 input_line_pointer
++;
153 digit_2
= input_line_pointer
;
154 for (number
= 0; (digit
= hex_value
[c
]) < maxdig
; c
= *input_line_pointer
++)
156 number
= number
* radix
+ digit
;
158 /* c contains character after number. */
159 /* input_line_pointer->char after c. */
160 small
= input_line_pointer
- digit_2
< too_many_digits
;
164 * we saw a lot of digits. manufacture a bignum the hard way.
166 LITTLENUM_TYPE
*leader
; /*->high order littlenum of the bignum. */
167 LITTLENUM_TYPE
*pointer
; /*->littlenum we are frobbing now. */
170 leader
= generic_bignum
;
171 generic_bignum
[0] = 0;
172 generic_bignum
[1] = 0;
173 /* we could just use digit_2, but lets be mnemonic. */
174 input_line_pointer
= --digit_2
; /*->1st digit. */
175 c
= *input_line_pointer
++;
176 for (; (carry
= hex_value
[c
]) < maxdig
; c
= *input_line_pointer
++)
178 for (pointer
= generic_bignum
;
184 work
= carry
+ radix
* *pointer
;
185 *pointer
= work
& LITTLENUM_MASK
;
186 carry
= work
>> LITTLENUM_NUMBER_OF_BITS
;
190 if (leader
< generic_bignum
+ SIZE_OF_LARGE_NUMBER
- 1)
191 { /* room to grow a longer bignum. */
196 /* again, c is char after number, */
197 /* input_line_pointer->after c. */
198 know (sizeof (int) * 8 == 32);
199 know (LITTLENUM_NUMBER_OF_BITS
== 16);
200 /* hence the constant "2" in the next line. */
201 if (leader
< generic_bignum
+ 2)
202 { /* will fit into 32 bits. */
204 ((generic_bignum
[1] & LITTLENUM_MASK
) << LITTLENUM_NUMBER_OF_BITS
)
205 | (generic_bignum
[0] & LITTLENUM_MASK
);
210 number
= leader
- generic_bignum
+ 1; /* number of littlenums in the bignum. */
216 * here with number, in correct radix. c is the next char.
217 * note that unlike un*x, we allow "011f" "0x9f" to
218 * both mean the same as the (conventional) "9f". this is simply easier
219 * than checking for strict canonical form. syntax sux!
225 #ifdef LOCAL_LABELS_FB
229 * backward ref to local label.
230 * because it is backward, expect it to be defined.
232 /* Construct a local label. */
233 name
= fb_label_name ((int) number
, 0);
235 /* seen before, or symbol is defined: ok */
236 symbolP
= symbol_find (name
);
237 if ((symbolP
!= NULL
) && (S_IS_DEFINED (symbolP
)))
240 /* local labels are never absolute. don't waste time
241 checking absoluteness. */
242 know (SEG_NORMAL (S_GET_SEGMENT (symbolP
)));
244 expressionP
->X_add_symbol
= symbolP
;
245 expressionP
->X_seg
= S_GET_SEGMENT (symbolP
);
249 { /* either not seen or not defined. */
250 as_bad ("backw. ref to unknown label \"%d:\", 0 assumed.", number
);
251 expressionP
->X_seg
= SEG_ABSOLUTE
;
254 expressionP
->X_add_number
= 0;
261 * forward reference. expect symbol to be undefined or
262 * unknown. undefined: seen it before. unknown: never seen
264 * construct a local label name, then an undefined symbol.
265 * don't create a xseg frag for it: caller may do that.
266 * just return it as never seen before.
268 name
= fb_label_name ((int) number
, 1);
269 symbolP
= symbol_find_or_make (name
);
270 /* we have no need to check symbol properties. */
271 #ifndef many_segments
272 /* since "know" puts its arg into a "string", we
273 can't have newlines in the argument. */
274 know (S_GET_SEGMENT (symbolP
) == SEG_UNKNOWN
|| S_GET_SEGMENT (symbolP
) == SEG_TEXT
|| S_GET_SEGMENT (symbolP
) == SEG_DATA
);
276 expressionP
->X_add_symbol
= symbolP
;
277 expressionP
->X_seg
= SEG_UNKNOWN
;
278 expressionP
->X_subtract_symbol
= NULL
;
279 expressionP
->X_add_number
= 0;
284 #endif /* LOCAL_LABELS_FB */
286 #ifdef LOCAL_LABELS_DOLLAR
291 /* If the dollar label is *currently* defined, then this is just
292 another reference to it. If it is not *currently* defined,
293 then this is a fresh instantiation of that number, so create
296 if (dollar_label_defined (number
))
298 name
= dollar_label_name (number
, 0);
299 symbolP
= symbol_find (name
);
300 know (symbolP
!= NULL
);
304 name
= dollar_label_name (number
, 1);
305 symbolP
= symbol_find_or_make (name
);
308 expressionP
->X_add_symbol
= symbolP
;
309 expressionP
->X_add_number
= 0;
310 expressionP
->X_seg
= S_GET_SEGMENT (symbolP
);
315 #endif /* LOCAL_LABELS_DOLLAR */
319 expressionP
->X_add_number
= number
;
320 expressionP
->X_seg
= SEG_ABSOLUTE
;
321 input_line_pointer
--; /* restore following character. */
323 } /* really just a number */
325 } /* switch on char following the number */
330 { /* not a small number */
331 expressionP
->X_add_number
= number
;
332 expressionP
->X_seg
= SEG_BIG
;
333 input_line_pointer
--; /*->char following number. */
335 } /* integer_constant() */
339 * Summary of operand().
341 * in: Input_line_pointer points to 1st char of operand, which may
344 * out: A expressionS. X_seg determines how to understand the rest of the
346 * The operand may have been empty: in this case X_seg == SEG_ABSENT.
347 * Input_line_pointer->(next non-blank) char after operand.
354 operand (expressionP
)
355 register expressionS
*expressionP
;
358 register symbolS
*symbolP
; /* points to symbol */
359 register char *name
; /* points to name of symbol */
360 /* invented for humans only, hope */
361 /* optimising compiler flushes it! */
362 register short int radix
; /* 2, 8, 10 or 16, 0 when floating */
363 /* 0 means we saw start of a floating- */
364 /* point constant. */
366 /* digits, assume it is a bignum. */
368 SKIP_WHITESPACE (); /* leading whitespace is part of operand. */
369 c
= *input_line_pointer
++; /* input_line_pointer->past char in c. */
375 integer_constant (2, expressionP
);
378 integer_constant (8, expressionP
);
381 integer_constant (16, expressionP
);
393 input_line_pointer
--;
395 integer_constant (10, expressionP
);
399 /* non-decimal radix */
402 c
= *input_line_pointer
;
407 if (c
&& strchr (FLT_CHARS
, c
))
409 input_line_pointer
++;
410 floating_constant (expressionP
);
414 /* The string was only zero */
415 expressionP
->X_add_symbol
= 0;
416 expressionP
->X_add_number
= 0;
417 expressionP
->X_seg
= SEG_ABSOLUTE
;
424 input_line_pointer
++;
425 integer_constant (16, expressionP
);
429 #ifdef LOCAL_LABELS_FB
430 if (!*input_line_pointer
431 || (!strchr ("+-.0123456789", *input_line_pointer
)
432 && !strchr (EXP_CHARS
, *input_line_pointer
)))
434 input_line_pointer
--;
435 integer_constant (10, expressionP
);
440 input_line_pointer
++;
441 integer_constant (2, expressionP
);
452 integer_constant (8, expressionP
);
456 #ifdef LOCAL_LABELS_FB
457 /* if it says '0f' and the line ends or it doesn't look like
458 a floating point #, its a local label ref. dtrt */
459 /* likewise for the b's. xoxorich. */
461 && (!*input_line_pointer
||
462 (!strchr ("+-.0123456789", *input_line_pointer
) &&
463 !strchr (EXP_CHARS
, *input_line_pointer
))))
465 input_line_pointer
-= 1;
466 integer_constant (10, expressionP
);
480 input_line_pointer
++;
481 floating_constant (expressionP
);
484 #ifdef LOCAL_LABELS_DOLLAR
486 integer_constant (10, expressionP
);
493 /* didn't begin with digit & not a name */
495 (void) expression (expressionP
);
496 /* Expression() will pass trailing whitespace */
497 if (*input_line_pointer
++ != ')')
499 as_bad ("Missing ')' assumed");
500 input_line_pointer
--;
502 /* here with input_line_pointer->char after "(...)" */
504 return expressionP
->X_seg
;
508 /* Warning: to conform to other people's assemblers NO ESCAPEMENT is
509 permitted for a single quote. The next character, parity errors and
510 all, is taken as the value of the operand. VERY KINKY. */
511 expressionP
->X_add_number
= *input_line_pointer
++;
512 expressionP
->X_seg
= SEG_ABSOLUTE
;
520 /* unary operator: hope for SEG_ABSOLUTE */
521 switch (operand (expressionP
))
524 /* input_line_pointer -> char after operand */
527 expressionP
->X_add_number
= -expressionP
->X_add_number
;
528 /* Notice: '-' may overflow: no warning is given. This is
529 compatible with other people's assemblers. Sigh. */
533 expressionP
->X_add_number
= ~expressionP
->X_add_number
;
543 { /* JF I hope this hack works */
544 expressionP
->X_subtract_symbol
= expressionP
->X_add_symbol
;
545 expressionP
->X_add_symbol
= 0;
546 expressionP
->X_seg
= SEG_DIFFERENCE
;
549 default: /* unary on non-absolute is unsuported */
550 as_warn ("Unary operator %c ignored because bad operand follows", c
);
552 /* Expression undisturbed from operand(). */
561 if (!is_part_of_name (*input_line_pointer
))
564 extern struct obstack frags
;
566 /* JF: '.' is pseudo symbol with value of current location
567 in current segment. */
568 #ifdef DOT_LABEL_PREFIX
573 symbolP
= symbol_new (fake
,
575 (valueT
) (obstack_next_free (&frags
) - frag_now
->fr_literal
),
578 expressionP
->X_add_number
= 0;
579 expressionP
->X_add_symbol
= symbolP
;
580 expressionP
->X_seg
= now_seg
;
593 /* can't imagine any other kind of operand */
594 expressionP
->X_seg
= SEG_ABSENT
;
595 input_line_pointer
--;
596 md_operand (expressionP
);
600 if (is_end_of_line
[c
])
602 if (is_name_beginner (c
)) /* here if did not begin with a digit */
605 * Identifier begins here.
606 * This is kludged for speed, so code is repeated.
609 name
= --input_line_pointer
;
610 c
= get_symbol_end ();
611 symbolP
= symbol_find_or_make (name
);
612 /* If we have an absolute symbol or a reg, then we know its value
614 expressionP
->X_seg
= S_GET_SEGMENT (symbolP
);
615 switch (expressionP
->X_seg
)
619 expressionP
->X_add_number
= S_GET_VALUE (symbolP
);
623 expressionP
->X_add_number
= 0;
624 expressionP
->X_add_symbol
= symbolP
;
626 *input_line_pointer
= c
;
627 expressionP
->X_subtract_symbol
= NULL
;
631 as_bad ("Bad expression");
632 expressionP
->X_add_number
= 0;
633 expressionP
->X_seg
= SEG_ABSOLUTE
;
646 * It is more 'efficient' to clean up the expressionS when they are created.
647 * Doing it here saves lines of code.
649 clean_up_expression (expressionP
);
650 SKIP_WHITESPACE (); /*->1st char after operand. */
651 know (*input_line_pointer
!= ' ');
652 return (expressionP
->X_seg
);
656 /* Internal. Simplify a struct expression for use by expr() */
659 * In: address of a expressionS.
660 * The X_seg field of the expressionS may only take certain values.
661 * Now, we permit SEG_PASS1 to make code smaller & faster.
662 * Elsewise we waste time special-case testing. Sigh. Ditto SEG_ABSENT.
663 * Out: expressionS may have been modified:
664 * 'foo-foo' symbol references cancelled to 0,
665 * which changes X_seg from SEG_DIFFERENCE to SEG_ABSOLUTE;
666 * Unused fields zeroed to help expr().
670 clean_up_expression (expressionP
)
671 register expressionS
*expressionP
;
673 switch (expressionP
->X_seg
)
677 expressionP
->X_add_symbol
= NULL
;
678 expressionP
->X_subtract_symbol
= NULL
;
679 expressionP
->X_add_number
= 0;
684 expressionP
->X_subtract_symbol
= NULL
;
685 expressionP
->X_add_symbol
= NULL
;
689 expressionP
->X_subtract_symbol
= NULL
;
694 * It does not hurt to 'cancel' NULL==NULL
695 * when comparing symbols for 'eq'ness.
696 * It is faster to re-cancel them to NULL
697 * than to check for this special case.
699 if (expressionP
->X_subtract_symbol
== expressionP
->X_add_symbol
700 || (expressionP
->X_subtract_symbol
701 && expressionP
->X_add_symbol
702 && expressionP
->X_subtract_symbol
->sy_frag
== expressionP
->X_add_symbol
->sy_frag
703 && S_GET_VALUE (expressionP
->X_subtract_symbol
) == S_GET_VALUE (expressionP
->X_add_symbol
)))
705 expressionP
->X_subtract_symbol
= NULL
;
706 expressionP
->X_add_symbol
= NULL
;
707 expressionP
->X_seg
= SEG_ABSOLUTE
;
712 expressionP
->X_add_symbol
= NULL
;
713 expressionP
->X_subtract_symbol
= NULL
;
717 if (SEG_NORMAL (expressionP
->X_seg
))
719 expressionP
->X_subtract_symbol
= NULL
;
723 BAD_CASE (expressionP
->X_seg
);
727 } /* clean_up_expression() */
732 * Internal. Made a function because this code is used in 2 places.
733 * Generate error or correct X_?????_symbol of expressionS.
737 * symbol_1 += symbol_2 ... well ... sort of.
741 expr_part (symbol_1_PP
, symbol_2_P
)
742 symbolS
**symbol_1_PP
;
746 #ifndef MANY_SEGMENTS
747 know ((*symbol_1_PP
) == NULL
|| (S_GET_SEGMENT (*symbol_1_PP
) == SEG_TEXT
) || (S_GET_SEGMENT (*symbol_1_PP
) == SEG_DATA
) || (S_GET_SEGMENT (*symbol_1_PP
) == SEG_BSS
) || (!S_IS_DEFINED (*symbol_1_PP
)));
748 know (symbol_2_P
== NULL
|| (S_GET_SEGMENT (symbol_2_P
) == SEG_TEXT
) || (S_GET_SEGMENT (symbol_2_P
) == SEG_DATA
) || (S_GET_SEGMENT (symbol_2_P
) == SEG_BSS
) || (!S_IS_DEFINED (symbol_2_P
)));
752 if (!S_IS_DEFINED (*symbol_1_PP
))
756 return_value
= SEG_PASS1
;
761 know (!S_IS_DEFINED (*symbol_1_PP
));
762 return_value
= SEG_UNKNOWN
;
769 if (!S_IS_DEFINED (symbol_2_P
))
772 return_value
= SEG_PASS1
;
776 /* {seg1} - {seg2} */
777 as_bad ("Expression too complex, 2 symbolS forgotten: \"%s\" \"%s\"",
778 S_GET_NAME (*symbol_1_PP
), S_GET_NAME (symbol_2_P
));
780 return_value
= SEG_ABSOLUTE
;
785 return_value
= S_GET_SEGMENT (*symbol_1_PP
);
790 { /* (* symbol_1_PP) == NULL */
793 *symbol_1_PP
= symbol_2_P
;
794 return_value
= S_GET_SEGMENT (symbol_2_P
);
799 return_value
= SEG_ABSOLUTE
;
802 #ifndef MANY_SEGMENTS
803 know (return_value
== SEG_ABSOLUTE
|| return_value
== SEG_TEXT
|| return_value
== SEG_DATA
|| return_value
== SEG_BSS
|| return_value
== SEG_UNKNOWN
|| return_value
== SEG_PASS1
);
805 know ((*symbol_1_PP
) == NULL
|| (S_GET_SEGMENT (*symbol_1_PP
) == return_value
));
806 return (return_value
);
809 /* Expression parser. */
812 * We allow an empty expression, and just assume (absolute,0) silently.
813 * Unary operators and parenthetical expressions are treated as operands.
814 * As usual, Q==quantity==operand, O==operator, X==expression mnemonics.
816 * We used to do a aho/ullman shift-reduce parser, but the logic got so
817 * warped that I flushed it and wrote a recursive-descent parser instead.
818 * Now things are stable, would anybody like to write a fast parser?
819 * Most expressions are either register (which does not even reach here)
820 * or 1 symbol. Then "symbol+constant" and "symbol-symbol" are common.
821 * So I guess it doesn't really matter how inefficient more complex expressions
824 * After expr(RANK,resultP) input_line_pointer->operator of rank <= RANK.
825 * Also, we have consumed any leading or trailing spaces (operand does that)
826 * and done all intervening operators.
831 O_illegal
, /* (0) what we get for illegal op */
833 O_multiply
, /* (1) * */
834 O_divide
, /* (2) / */
835 O_modulus
, /* (3) % */
836 O_left_shift
, /* (4) < */
837 O_right_shift
, /* (5) > */
838 O_bit_inclusive_or
, /* (6) | */
839 O_bit_or_not
, /* (7) ! */
840 O_bit_exclusive_or
, /* (8) ^ */
841 O_bit_and
, /* (9) & */
843 O_subtract
/* (11) - */
850 static const operatorT op_encoding
[256] =
851 { /* maps ASCII->operators */
853 __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
,
854 __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
,
856 __
, O_bit_or_not
, __
, __
, __
, O_modulus
, O_bit_and
, __
,
857 __
, __
, O_multiply
, O_add
, __
, O_subtract
, __
, O_divide
,
858 __
, __
, __
, __
, __
, __
, __
, __
,
859 __
, __
, __
, __
, O_left_shift
, __
, O_right_shift
, __
,
860 __
, __
, __
, __
, __
, __
, __
, __
,
861 __
, __
, __
, __
, __
, __
, __
, __
,
862 __
, __
, __
, __
, __
, __
, __
, __
,
863 __
, __
, __
, __
, __
, __
, O_bit_exclusive_or
, __
,
864 __
, __
, __
, __
, __
, __
, __
, __
,
865 __
, __
, __
, __
, __
, __
, __
, __
,
866 __
, __
, __
, __
, __
, __
, __
, __
,
867 __
, __
, __
, __
, O_bit_inclusive_or
, __
, __
, __
,
869 __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
,
870 __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
,
871 __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
,
872 __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
, __
,
873 __
, __
, __
, __
, __
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882 * 0 operand, (expression)
887 static const operator_rankT
889 {0, 3, 3, 3, 3, 3, 2, 2, 2, 2, 1, 1};
891 /* Return resultP->X_seg. */
894 register operator_rankT rank
; /* Larger # is higher rank. */
895 register expressionS
*resultP
; /* Deliver result here. */
898 register operatorT op_left
;
899 register char c_left
; /* 1st operator character. */
900 register operatorT op_right
;
901 register char c_right
;
904 (void) operand (resultP
);
905 know (*input_line_pointer
!= ' '); /* Operand() gobbles spaces. */
906 c_left
= *input_line_pointer
; /* Potential operator character. */
907 op_left
= op_encoding
[c_left
];
908 while (op_left
!= O_illegal
&& op_rank
[(int) op_left
] > rank
)
910 input_line_pointer
++; /*->after 1st character of operator. */
911 /* Operators "<<" and ">>" have 2 characters. */
912 if (*input_line_pointer
== c_left
&& (c_left
== '<' || c_left
== '>'))
914 input_line_pointer
++;
915 } /*->after operator. */
916 if (SEG_ABSENT
== expr (op_rank
[(int) op_left
], &right
))
918 as_warn ("Missing operand value assumed absolute 0.");
919 resultP
->X_add_number
= 0;
920 resultP
->X_subtract_symbol
= NULL
;
921 resultP
->X_add_symbol
= NULL
;
922 resultP
->X_seg
= SEG_ABSOLUTE
;
924 know (*input_line_pointer
!= ' ');
925 c_right
= *input_line_pointer
;
926 op_right
= op_encoding
[c_right
];
927 if (*input_line_pointer
== c_right
&& (c_right
== '<' || c_right
== '>'))
929 input_line_pointer
++;
930 } /*->after operator. */
931 know ((int) op_right
== 0 || op_rank
[(int) op_right
] <= op_rank
[(int) op_left
]);
932 /* input_line_pointer->after right-hand quantity. */
933 /* left-hand quantity in resultP */
934 /* right-hand quantity in right. */
935 /* operator in op_left. */
936 if (resultP
->X_seg
== SEG_PASS1
|| right
.X_seg
== SEG_PASS1
)
938 resultP
->X_seg
= SEG_PASS1
;
942 if (resultP
->X_seg
== SEG_BIG
)
944 as_warn ("Left operand of %c is a %s. Integer 0 assumed.",
945 c_left
, resultP
->X_add_number
> 0 ? "bignum" : "float");
946 resultP
->X_seg
= SEG_ABSOLUTE
;
947 resultP
->X_add_symbol
= 0;
948 resultP
->X_subtract_symbol
= 0;
949 resultP
->X_add_number
= 0;
951 if (right
.X_seg
== SEG_BIG
)
953 as_warn ("Right operand of %c is a %s. Integer 0 assumed.",
954 c_left
, right
.X_add_number
> 0 ? "bignum" : "float");
955 right
.X_seg
= SEG_ABSOLUTE
;
956 right
.X_add_symbol
= 0;
957 right
.X_subtract_symbol
= 0;
958 right
.X_add_number
= 0;
960 if (op_left
== O_subtract
)
963 * Convert - into + by exchanging symbolS and negating number.
964 * I know -infinity can't be negated in 2's complement:
965 * but then it can't be subtracted either. This trick
966 * does not cause any further inaccuracy.
969 register symbolS
*symbolP
;
971 right
.X_add_number
= -right
.X_add_number
;
972 symbolP
= right
.X_add_symbol
;
973 right
.X_add_symbol
= right
.X_subtract_symbol
;
974 right
.X_subtract_symbol
= symbolP
;
977 right
.X_seg
= SEG_DIFFERENCE
;
982 if (op_left
== O_add
)
986 #ifndef MANY_SEGMENTS
988 know (resultP
->X_seg
== SEG_DATA
|| resultP
->X_seg
== SEG_TEXT
|| resultP
->X_seg
== SEG_BSS
|| resultP
->X_seg
== SEG_UNKNOWN
|| resultP
->X_seg
== SEG_DIFFERENCE
|| resultP
->X_seg
== SEG_ABSOLUTE
|| resultP
->X_seg
== SEG_PASS1
|| resultP
->X_seg
== SEG_REGISTER
);
990 know (right
.X_seg
== SEG_DATA
|| right
.X_seg
== SEG_TEXT
|| right
.X_seg
== SEG_BSS
|| right
.X_seg
== SEG_UNKNOWN
|| right
.X_seg
== SEG_DIFFERENCE
|| right
.X_seg
== SEG_ABSOLUTE
|| right
.X_seg
== SEG_PASS1
);
992 clean_up_expression (&right
);
993 clean_up_expression (resultP
);
995 seg1
= expr_part (&resultP
->X_add_symbol
, right
.X_add_symbol
);
996 seg2
= expr_part (&resultP
->X_subtract_symbol
, right
.X_subtract_symbol
);
997 if (seg1
== SEG_PASS1
|| seg2
== SEG_PASS1
)
1000 resultP
->X_seg
= SEG_PASS1
;
1002 else if (seg2
== SEG_ABSOLUTE
)
1003 resultP
->X_seg
= seg1
;
1004 else if (seg1
!= SEG_UNKNOWN
1005 && seg1
!= SEG_ABSOLUTE
1006 && seg2
!= SEG_UNKNOWN
1009 know (seg2
!= SEG_ABSOLUTE
);
1010 know (resultP
->X_subtract_symbol
);
1011 #ifndef MANY_SEGMENTS
1012 know (seg1
== SEG_TEXT
|| seg1
== SEG_DATA
|| seg1
== SEG_BSS
);
1013 know (seg2
== SEG_TEXT
|| seg2
== SEG_DATA
|| seg2
== SEG_BSS
);
1015 know (resultP
->X_add_symbol
);
1016 know (resultP
->X_subtract_symbol
);
1017 as_bad ("Expression too complex: forgetting %s - %s",
1018 S_GET_NAME (resultP
->X_add_symbol
),
1019 S_GET_NAME (resultP
->X_subtract_symbol
));
1020 resultP
->X_seg
= SEG_ABSOLUTE
;
1021 /* Clean_up_expression() will do the rest. */
1024 resultP
->X_seg
= SEG_DIFFERENCE
;
1026 resultP
->X_add_number
+= right
.X_add_number
;
1027 clean_up_expression (resultP
);
1031 if (resultP
->X_seg
== SEG_UNKNOWN
|| right
.X_seg
== SEG_UNKNOWN
)
1033 resultP
->X_seg
= SEG_PASS1
;
1038 resultP
->X_subtract_symbol
= NULL
;
1039 resultP
->X_add_symbol
= NULL
;
1040 /* Will be SEG_ABSOLUTE. */
1041 if (resultP
->X_seg
!= SEG_ABSOLUTE
|| right
.X_seg
!= SEG_ABSOLUTE
)
1043 as_bad ("Relocation error. Absolute 0 assumed.");
1044 resultP
->X_seg
= SEG_ABSOLUTE
;
1045 resultP
->X_add_number
= 0;
1051 case O_bit_inclusive_or
:
1052 resultP
->X_add_number
|= right
.X_add_number
;
1056 if (right
.X_add_number
)
1058 resultP
->X_add_number
%= right
.X_add_number
;
1062 as_warn ("Division by 0. 0 assumed.");
1063 resultP
->X_add_number
= 0;
1068 resultP
->X_add_number
&= right
.X_add_number
;
1072 resultP
->X_add_number
*= right
.X_add_number
;
1076 if (right
.X_add_number
)
1078 resultP
->X_add_number
/= right
.X_add_number
;
1082 as_warn ("Division by 0. 0 assumed.");
1083 resultP
->X_add_number
= 0;
1088 resultP
->X_add_number
<<= right
.X_add_number
;
1092 resultP
->X_add_number
>>= right
.X_add_number
;
1095 case O_bit_exclusive_or
:
1096 resultP
->X_add_number
^= right
.X_add_number
;
1100 resultP
->X_add_number
|= ~right
.X_add_number
;
1106 } /* switch(operator) */
1108 } /* If we have to force need_pass_2. */
1109 } /* If operator was +. */
1110 } /* If we didn't set need_pass_2. */
1112 } /* While next operator is >= this rank. */
1113 return (resultP
->X_seg
);
1119 * This lives here because it belongs equally in expr.c & read.c.
1120 * Expr.c is just a branch office read.c anyway, and putting it
1121 * here lessens the crowd at read.c.
1123 * Assume input_line_pointer is at start of symbol name.
1124 * Advance input_line_pointer past symbol name.
1125 * Turn that character into a '\0', returning its former value.
1126 * This allows a string compare (RMS wants symbol names to be strings)
1127 * of the symbol name.
1128 * There will always be a char following symbol name, because all good
1129 * lines end in end-of-line.
1136 while (is_part_of_name (c
= *input_line_pointer
++))
1138 *--input_line_pointer
= 0;
1144 get_single_number ()
1148 return exp
.X_add_number
;