1 /* tc-vax.c - vax-specific -
2 Copyright (C) 1987, 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. */
23 #include "obstack.h" /* For FRAG_APPEND_1_CHAR macro in "frags.h" */
25 /* These chars start a comment anywhere in a source file (except inside
27 const char comment_chars
[] = "#";
29 /* These chars only start a comment at the beginning of a line. */
30 /* Note that for the VAX the are the same as comment_chars above. */
31 const char line_comment_chars
[] = "#";
33 const char line_separator_chars
[] = "";
35 /* Chars that can be used to separate mant from exp in floating point nums */
36 const char EXP_CHARS
[] = "eE";
38 /* Chars that mean this number is a floating point constant */
40 /* or 0H1.234E-12 (see exp chars above) */
41 const char FLT_CHARS
[] = "dDfFgGhH";
43 /* Also be aware that MAXIMUM_NUMBER_OF_CHARS_FOR_FLOAT may have to be
44 changed in read.c . Ideally it shouldn't have to know about it at all,
45 but nothing is ideal around here. */
47 /* Hold details of an operand expression */
48 static expressionS exp_of_operand
[VIT_MAX_OPERANDS
];
49 static segT seg_of_operand
[VIT_MAX_OPERANDS
];
51 /* A vax instruction after decoding. */
54 /* Hold details of big operands. */
55 LITTLENUM_TYPE big_operand_bits
[VIT_MAX_OPERANDS
][SIZE_OF_LARGE_NUMBER
];
56 FLONUM_TYPE float_operand
[VIT_MAX_OPERANDS
];
57 /* Above is made to point into big_operand_bits by md_begin(). */
60 * For VAX, relative addresses of "just the right length" are easy.
61 * The branch displacement is always the last operand, even in
62 * synthetic instructions.
63 * For VAX, we encode the relax_substateTs (in e.g. fr_substate) as:
65 * 4 3 2 1 0 bit number
66 * ---/ /--+-------+-------+-------+-------+-------+
67 * | what state ? | how long ? |
68 * ---/ /--+-------+-------+-------+-------+-------+
70 * The "how long" bits are 00=byte, 01=word, 10=long.
71 * This is a Un*x convention.
72 * Not all lengths are legit for a given value of (what state).
73 * The "how long" refers merely to the displacement length.
74 * The address usually has some constant bytes in it as well.
77 groups for VAX address relaxing.
80 length of byte, word, long
82 2a. J<cond> where <cond> is a simple flag test.
83 length of byte, word, long.
84 VAX opcodes are: (Hex)
97 Always, you complement 0th bit to reverse condition.
98 Always, 1-byte opcode, then 1-byte displacement.
100 2b. J<cond> where cond tests a memory bit.
101 length of byte, word, long.
102 Vax opcodes are: (Hex)
111 Always, you complement 0th bit to reverse condition.
112 Always, 1-byte opcde, longword-address, byte-address, 1-byte-displacement
114 2c. J<cond> where cond tests low-order memory bit
115 length of byte,word,long.
116 Vax opcodes are: (Hex)
119 Always, you complement 0th bit to reverse condition.
120 Always, 1-byte opcode, longword-address, 1-byte displacement.
123 length of byte,word,long.
124 Vax opcodes are: (Hex)
127 These are like (2) but there is no condition to reverse.
128 Always, 1 byte opcode, then displacement/absolute.
131 length of word, long.
132 Vax opcodes are: (Hex)
140 Always, we cannot reverse the sense of the branch; we have a word
142 The double-byte op-codes don't hurt: we never want to modify the
143 opcode, so we don't care how many bytes are between the opcode and
147 length of long, long, byte.
148 Vax opcodes are: (Hex)
153 Always, we cannot reverse the sense of the branch; we have a byte
156 The only time we need to modify the opcode is for class 2 instructions.
157 After relax() we may complement the lowest order bit of such instruction
158 to reverse sense of branch.
160 For class 2 instructions, we store context of "where is the opcode literal".
161 We can change an opcode's lowest order bit without breaking anything else.
163 We sometimes store context in the operand literal. This way we can figure out
164 after relax() what the original addressing mode was.
167 /* These displacements are relative to the start address of the
168 displacement. The first letter is Byte, Word. 2nd letter is
169 Forward, Backward. */
172 #define WF (2+ 32767)
173 #define WB (2+-32768)
174 /* Dont need LF, LB because they always reach. [They are coded as 0.] */
177 #define C(a,b) ENCODE_RELAX(a,b)
178 /* This macro has no side-effects. */
179 #define ENCODE_RELAX(what,length) (((what) << 2) + (length))
184 {1, 1, 0, 0}, /* error sentinel 0,0 */
185 {1, 1, 0, 0}, /* unused 0,1 */
186 {1, 1, 0, 0}, /* unused 0,2 */
187 {1, 1, 0, 0}, /* unused 0,3 */
188 {BF
+ 1, BB
+ 1, 2, C (1, 1)},/* B^"foo" 1,0 */
189 {WF
+ 1, WB
+ 1, 3, C (1, 2)},/* W^"foo" 1,1 */
190 {0, 0, 5, 0}, /* L^"foo" 1,2 */
191 {1, 1, 0, 0}, /* unused 1,3 */
192 {BF
, BB
, 1, C (2, 1)}, /* b<cond> B^"foo" 2,0 */
193 {WF
+ 2, WB
+ 2, 4, C (2, 2)},/* br.+? brw X 2,1 */
194 {0, 0, 7, 0}, /* br.+? jmp X 2,2 */
195 {1, 1, 0, 0}, /* unused 2,3 */
196 {BF
, BB
, 1, C (3, 1)}, /* brb B^foo 3,0 */
197 {WF
, WB
, 2, C (3, 2)}, /* brw W^foo 3,1 */
198 {0, 0, 5, 0}, /* Jmp L^foo 3,2 */
199 {1, 1, 0, 0}, /* unused 3,3 */
200 {1, 1, 0, 0}, /* unused 4,0 */
201 {WF
, WB
, 2, C (4, 2)}, /* acb_ ^Wfoo 4,1 */
202 {0, 0, 10, 0}, /* acb_,br,jmp L^foo4,2 */
203 {1, 1, 0, 0}, /* unused 4,3 */
204 {BF
, BB
, 1, C (5, 1)}, /* Xob___,,foo 5,0 */
205 {WF
+ 4, WB
+ 4, 6, C (5, 2)},/* Xob.+2,brb.+3,brw5,1 */
206 {0, 0, 9, 0}, /* Xob.+2,brb.+6,jmp5,2 */
217 const pseudo_typeS md_pseudo_table
[] =
219 {"dfloat", float_cons
, 'd'},
220 {"ffloat", float_cons
, 'f'},
221 {"gfloat", float_cons
, 'g'},
222 {"hfloat", float_cons
, 'h'},
226 #define STATE_PC_RELATIVE (1)
227 #define STATE_CONDITIONAL_BRANCH (2)
228 #define STATE_ALWAYS_BRANCH (3) /* includes BSB... */
229 #define STATE_COMPLEX_BRANCH (4)
230 #define STATE_COMPLEX_HOP (5)
232 #define STATE_BYTE (0)
233 #define STATE_WORD (1)
234 #define STATE_LONG (2)
235 #define STATE_UNDF (3) /* Symbol undefined in pass1 */
238 #define min(a, b) ((a) < (b) ? (a) : (b))
240 int flonum_gen2vax
PARAMS ((char format_letter
, FLONUM_TYPE
* f
,
241 LITTLENUM_TYPE
* words
));
242 static const char *vip_begin
PARAMS ((int, char *, char *, char *));
243 static void vip_op_defaults
PARAMS ((char *immediate
, char *indirect
,
245 static void vip_op
PARAMS ((char *, struct vop
*));
246 static void vip
PARAMS ((struct vit
*, char *));
255 if (errtxt
= vip_begin (1, "$", "*", "`"))
257 as_fatal ("VIP_BEGIN error:%s", errtxt
);
260 for (i
= 0, fP
= float_operand
;
261 fP
< float_operand
+ VIT_MAX_OPERANDS
;
264 fP
->low
= &big_operand_bits
[i
][0];
265 fP
->high
= &big_operand_bits
[i
][SIZE_OF_LARGE_NUMBER
- 1];
270 md_number_to_chars (con
, value
, nbytes
)
275 number_to_chars_littleendian (con
, value
, nbytes
);
278 /* Fix up some data or instructions after we find out the value of a symbol
279 that they reference. */
281 void /* Knows about order of bytes in address. */
282 md_apply_fix (fixP
, value
)
286 number_to_chars_littleendian (fixP
->fx_where
+ fixP
->fx_frag
->fr_literal
,
287 (valueT
) value
, fixP
->fx_size
);
291 md_chars_to_number (con
, nbytes
)
292 unsigned char con
[]; /* Low order byte 1st. */
293 int nbytes
; /* Number of bytes in the input. */
296 for (retval
= 0, con
+= nbytes
- 1; nbytes
--; con
--)
298 retval
<<= BITS_PER_CHAR
;
304 /* vax:md_assemble() emit frags for 1 instruction */
307 md_assemble (instruction_string
)
308 char *instruction_string
; /* A string: assemble 1 instruction. */
310 /* Non-zero if operand expression's segment is not known yet. */
315 /* An operand. Scans all operands. */
316 struct vop
*operandP
;
317 char *save_input_line_pointer
;
318 /* What used to live after an expression. */
320 /* 1: instruction_string bad for all passes. */
322 /* Points to slot just after last operand. */
323 struct vop
*end_operandP
;
324 /* Points to expression values for this operand. */
328 /* These refer to an instruction operand expression. */
329 /* Target segment of the address. */
331 valueT this_add_number
;
332 /* Positive (minuend) symbol. */
333 struct symbol
*this_add_symbol
;
335 long opcode_as_number
;
336 /* Least significant byte 1st. */
337 char *opcode_as_chars
;
338 /* As an array of characters. */
339 /* Least significant byte 1st */
340 char *opcode_low_byteP
;
341 /* length (bytes) meant by vop_short. */
343 /* 0, or 1 if '@' is in addressing mode. */
345 /* From vop_nbytes: vax_operand_width (in bytes) */
348 LITTLENUM_TYPE literal_float
[8];
349 /* Big enough for any floating point literal. */
351 vip (&v
, instruction_string
);
354 * Now we try to find as many as_warn()s as we can. If we do any as_warn()s
355 * then goofed=1. Notice that we don't make any frags yet.
356 * Should goofed be 1, then this instruction will wedge in any pass,
357 * and we can safely flush it, without causing interpass symbol phase
358 * errors. That is, without changing label values in different passes.
360 if (goofed
= (*v
.vit_error
))
362 as_warn ("Ignoring statement due to \"%s\"", v
.vit_error
);
365 * We need to use expression() and friends, which require us to diddle
366 * input_line_pointer. So we save it and restore it later.
368 save_input_line_pointer
= input_line_pointer
;
369 for (operandP
= v
.vit_operand
,
370 expP
= exp_of_operand
,
371 segP
= seg_of_operand
,
372 floatP
= float_operand
,
373 end_operandP
= v
.vit_operand
+ v
.vit_operands
;
375 operandP
< end_operandP
;
377 operandP
++, expP
++, segP
++, floatP
++)
378 { /* for each operand */
379 if (operandP
->vop_error
)
381 as_warn ("Ignoring statement because \"%s\"", operandP
->vop_error
);
386 /* statement has no syntax goofs: lets sniff the expression */
387 int can_be_short
= 0; /* 1 if a bignum can be reduced to a short literal. */
389 input_line_pointer
= operandP
->vop_expr_begin
;
390 c_save
= operandP
->vop_expr_end
[1];
391 operandP
->vop_expr_end
[1] = '\0';
392 /* If to_seg == SEG_PASS1, expression() will have set need_pass_2 = 1. */
393 *segP
= expression (expP
);
397 /* for BSD4.2 compatibility, missing expression is absolute 0 */
398 expP
->X_op
= O_constant
;
399 expP
->X_add_number
= 0;
400 /* For SEG_ABSOLUTE, we shouldn't need to set X_op_symbol,
401 X_add_symbol to any particular value. But, we will program
402 defensively. Since this situation occurs rarely so it costs
403 us little to do, and stops Dean worrying about the origin of
404 random bits in expressionS's. */
405 expP
->X_add_symbol
= NULL
;
406 expP
->X_op_symbol
= NULL
;
415 * Major bug. We can't handle the case of a
416 * SEG_OP expression in a VIT_OPCODE_SYNTHETIC
417 * variable-length instruction.
418 * We don't have a frag type that is smart enough to
419 * relax a SEG_OP, and so we just force all
420 * SEG_OPs to behave like SEG_PASS1s.
421 * Clearly, if there is a demand we can invent a new or
422 * modified frag type and then coding up a frag for this
423 * case will be easy. SEG_OP was invented for the
424 * .words after a CASE opcode, and was never intended for
425 * instruction operands.
428 as_warn ("Can't relocate expression");
432 /* Preserve the bits. */
433 if (expP
->X_add_number
> 0)
435 bignum_copy (generic_bignum
, expP
->X_add_number
,
436 floatP
->low
, SIZE_OF_LARGE_NUMBER
);
440 know (expP
->X_add_number
< 0);
441 flonum_copy (&generic_floating_point_number
,
443 if (strchr ("s i", operandP
->vop_short
))
445 /* Could possibly become S^# */
446 flonum_gen2vax (-expP
->X_add_number
, floatP
, literal_float
);
447 switch (-expP
->X_add_number
)
451 (literal_float
[0] & 0xFC0F) == 0x4000
452 && literal_float
[1] == 0;
457 (literal_float
[0] & 0xFC0F) == 0x4000
458 && literal_float
[1] == 0
459 && literal_float
[2] == 0
460 && literal_float
[3] == 0;
465 (literal_float
[0] & 0xFF81) == 0x4000
466 && literal_float
[1] == 0
467 && literal_float
[2] == 0
468 && literal_float
[3] == 0;
472 can_be_short
= ((literal_float
[0] & 0xFFF8) == 0x4000
473 && (literal_float
[1] & 0xE000) == 0
474 && literal_float
[2] == 0
475 && literal_float
[3] == 0
476 && literal_float
[4] == 0
477 && literal_float
[5] == 0
478 && literal_float
[6] == 0
479 && literal_float
[7] == 0);
483 BAD_CASE (-expP
->X_add_number
);
485 } /* switch (float type) */
486 } /* if (could want to become S^#...) */
487 } /* bignum or flonum ? */
489 if (operandP
->vop_short
== 's'
490 || operandP
->vop_short
== 'i'
491 || (operandP
->vop_short
== ' '
492 && operandP
->vop_reg
== 0xF
493 && (operandP
->vop_mode
& 0xE) == 0x8))
496 if (operandP
->vop_short
== ' ')
498 /* We must chose S^ or I^. */
499 if (expP
->X_add_number
> 0)
501 /* Bignum: Short literal impossible. */
502 operandP
->vop_short
= 'i';
503 operandP
->vop_mode
= 8;
504 operandP
->vop_reg
= 0xF; /* VAX PC. */
508 /* Flonum: Try to do it. */
511 operandP
->vop_short
= 's';
512 operandP
->vop_mode
= 0;
513 operandP
->vop_ndx
= -1;
514 operandP
->vop_reg
= -1;
515 expP
->X_op
= O_constant
;
519 operandP
->vop_short
= 'i';
520 operandP
->vop_mode
= 8;
521 operandP
->vop_reg
= 0xF; /* VAX PC */
523 } /* bignum or flonum ? */
524 } /* if #, but no S^ or I^ seen. */
525 /* No more ' ' case: either 's' or 'i'. */
526 if (operandP
->vop_short
== 's')
528 /* Wants to be a short literal. */
529 if (expP
->X_add_number
> 0)
531 as_warn ("Bignum not permitted in short literal. Immediate mode assumed.");
532 operandP
->vop_short
= 'i';
533 operandP
->vop_mode
= 8;
534 operandP
->vop_reg
= 0xF; /* VAX PC. */
540 as_warn ("Can't do flonum short literal: immediate mode used.");
541 operandP
->vop_short
= 'i';
542 operandP
->vop_mode
= 8;
543 operandP
->vop_reg
= 0xF; /* VAX PC. */
546 { /* Encode short literal now. */
549 switch (-expP
->X_add_number
)
553 temp
= literal_float
[0] >> 4;
557 temp
= literal_float
[0] >> 1;
561 temp
= ((literal_float
[0] << 3) & 070)
562 | ((literal_float
[1] >> 13) & 07);
566 BAD_CASE (-expP
->X_add_number
);
570 floatP
->low
[0] = temp
& 077;
572 } /* if can be short literal float */
573 } /* flonum or bignum ? */
576 { /* I^# seen: set it up if float. */
577 if (expP
->X_add_number
< 0)
579 memcpy (floatP
->low
, literal_float
, sizeof (literal_float
));
585 as_warn ("A bignum/flonum may not be a displacement: 0x%x used",
586 expP
->X_add_number
= 0x80000000);
587 /* Chosen so luser gets the most offset bits to patch later. */
589 expP
->X_add_number
= floatP
->low
[0]
590 | ((LITTLENUM_MASK
& (floatP
->low
[1])) << LITTLENUM_NUMBER_OF_BITS
);
592 * For the SEG_BIG case we have:
593 * If vop_short == 's' then a short floating literal is in the
594 * lowest 6 bits of floatP -> low [0], which is
595 * big_operand_bits [---] [0].
596 * If vop_short == 'i' then the appropriate number of elements
597 * of big_operand_bits [---] [...] are set up with the correct
599 * Also, just in case width is byte word or long, we copy the lowest
600 * 32 bits of the number to X_add_number.
604 if (input_line_pointer
!= operandP
->vop_expr_end
+ 1)
606 as_warn ("Junk at end of expression \"%s\"", input_line_pointer
);
609 operandP
->vop_expr_end
[1] = c_save
;
611 } /* for(each operand) */
613 input_line_pointer
= save_input_line_pointer
;
615 if (need_pass_2
|| goofed
)
622 /* Remember where it is, in case we want to modify the op-code later. */
623 opcode_low_byteP
= frag_more (v
.vit_opcode_nbytes
);
624 memcpy (opcode_low_byteP
, v
.vit_opcode
, v
.vit_opcode_nbytes
);
625 opcode_as_number
= md_chars_to_number (opcode_as_chars
= v
.vit_opcode
, 4);
626 for (operandP
= v
.vit_operand
,
627 expP
= exp_of_operand
,
628 segP
= seg_of_operand
,
629 floatP
= float_operand
,
630 end_operandP
= v
.vit_operand
+ v
.vit_operands
;
632 operandP
< end_operandP
;
639 if (operandP
->vop_ndx
>= 0)
641 /* indexed addressing byte */
642 /* Legality of indexed mode already checked: it is OK */
643 FRAG_APPEND_1_CHAR (0x40 + operandP
->vop_ndx
);
644 } /* if(vop_ndx>=0) */
646 /* Here to make main operand frag(s). */
647 this_add_number
= expP
->X_add_number
;
648 this_add_symbol
= expP
->X_add_symbol
;
650 is_undefined
= (to_seg
== SEG_UNKNOWN
);
651 know (to_seg
== SEG_UNKNOWN
652 || to_seg
== SEG_ABSOLUTE
653 || to_seg
== SEG_DATA
654 || to_seg
== SEG_TEXT
656 || to_seg
== SEG_BIG
);
657 at
= operandP
->vop_mode
& 1;
658 length
= (operandP
->vop_short
== 'b'
659 ? 1 : (operandP
->vop_short
== 'w'
660 ? 2 : (operandP
->vop_short
== 'l'
662 nbytes
= operandP
->vop_nbytes
;
663 if (operandP
->vop_access
== 'b')
665 if (to_seg
== now_seg
|| is_undefined
)
667 /* If is_undefined, then it might BECOME now_seg. */
670 p
= frag_more (nbytes
);
671 fix_new (frag_now
, p
- frag_now
->fr_literal
, nbytes
,
672 this_add_symbol
, this_add_number
, 1, NO_RELOC
);
675 { /* to_seg==now_seg || to_seg == SEG_UNKNOWN */
677 length_code
= is_undefined
? STATE_UNDF
: STATE_BYTE
;
678 if (opcode_as_number
& VIT_OPCODE_SPECIAL
)
680 if (operandP
->vop_width
== VAX_WIDTH_UNCONDITIONAL_JUMP
)
683 frag_var (rs_machine_dependent
, 5, 1,
684 ENCODE_RELAX (STATE_ALWAYS_BRANCH
, length_code
),
685 this_add_symbol
, this_add_number
,
690 if (operandP
->vop_width
== VAX_WIDTH_WORD_JUMP
)
692 length_code
= STATE_WORD
;
693 /* JF: There is no state_byte for this one! */
694 frag_var (rs_machine_dependent
, 10, 2,
695 ENCODE_RELAX (STATE_COMPLEX_BRANCH
, length_code
),
696 this_add_symbol
, this_add_number
,
701 know (operandP
->vop_width
== VAX_WIDTH_BYTE_JUMP
);
702 frag_var (rs_machine_dependent
, 9, 1,
703 ENCODE_RELAX (STATE_COMPLEX_HOP
, length_code
),
704 this_add_symbol
, this_add_number
,
711 know (operandP
->vop_width
== VAX_WIDTH_CONDITIONAL_JUMP
);
712 frag_var (rs_machine_dependent
, 7, 1,
713 ENCODE_RELAX (STATE_CONDITIONAL_BRANCH
, length_code
),
714 this_add_symbol
, this_add_number
,
721 /* to_seg != now_seg && to_seg != SEG_UNKNOWN */
723 * --- SEG FLOAT MAY APPEAR HERE ----
725 if (to_seg
== SEG_ABSOLUTE
)
729 know (!(opcode_as_number
& VIT_OPCODE_SYNTHETIC
));
730 p
= frag_more (nbytes
);
731 /* Conventional relocation. */
732 fix_new (frag_now
, p
- frag_now
->fr_literal
,
733 nbytes
, &abs_symbol
, this_add_number
,
738 know (opcode_as_number
& VIT_OPCODE_SYNTHETIC
);
739 if (opcode_as_number
& VIT_OPCODE_SPECIAL
)
741 if (operandP
->vop_width
== VAX_WIDTH_UNCONDITIONAL_JUMP
)
744 *opcode_low_byteP
= opcode_as_chars
[0] + VAX_WIDEN_LONG
;
745 know (opcode_as_chars
[1] == 0);
747 p
[0] = VAX_ABSOLUTE_MODE
; /* @#... */
748 md_number_to_chars (p
+ 1, this_add_number
, 4);
749 /* Now (eg) JMP @#foo or JSB @#foo. */
753 if (operandP
->vop_width
== VAX_WIDTH_WORD_JUMP
)
761 p
[5] = VAX_ABSOLUTE_MODE
; /* @#... */
762 md_number_to_chars (p
+ 6, this_add_number
, 4);
772 know (operandP
->vop_width
== VAX_WIDTH_BYTE_JUMP
);
778 p
[4] = VAX_PC_RELATIVE_MODE
+ 1; /* @#... */
779 md_number_to_chars (p
+ 5, this_add_number
, 4);
792 *opcode_low_byteP
^= 1;
793 /* To reverse the condition in a VAX branch,
794 complement the lowest order bit. */
798 p
[2] = VAX_ABSOLUTE_MODE
; /* @#... */
799 md_number_to_chars (p
+ 3, this_add_number
, 4);
810 /* to_seg != now_seg && to_seg != SEG_UNKNOWN && to_Seg != SEG_ABSOLUTE */
813 /* Pc-relative. Conventional relocation. */
814 know (!(opcode_as_number
& VIT_OPCODE_SYNTHETIC
));
815 p
= frag_more (nbytes
);
816 fix_new (frag_now
, p
- frag_now
->fr_literal
,
817 nbytes
, &abs_symbol
, this_add_number
,
822 know (opcode_as_number
& VIT_OPCODE_SYNTHETIC
);
823 if (opcode_as_number
& VIT_OPCODE_SPECIAL
)
825 if (operandP
->vop_width
== VAX_WIDTH_UNCONDITIONAL_JUMP
)
828 know (opcode_as_chars
[1] == 0);
829 *opcode_low_byteP
= opcode_as_chars
[0] + VAX_WIDEN_LONG
;
831 p
[0] = VAX_PC_RELATIVE_MODE
;
833 p
+ 1 - frag_now
->fr_literal
, 4,
835 this_add_number
, 1, NO_RELOC
);
836 /* Now eg JMP foo or JSB foo. */
840 if (operandP
->vop_width
== VAX_WIDTH_WORD_JUMP
)
848 p
[5] = VAX_PC_RELATIVE_MODE
;
850 p
+ 6 - frag_now
->fr_literal
, 4,
852 this_add_number
, 1, NO_RELOC
);
862 know (operandP
->vop_width
== VAX_WIDTH_BYTE_JUMP
);
868 p
[4] = VAX_PC_RELATIVE_MODE
;
870 p
+ 5 - frag_now
->fr_literal
,
872 this_add_number
, 1, NO_RELOC
);
884 know (operandP
->vop_width
== VAX_WIDTH_CONDITIONAL_JUMP
);
885 *opcode_low_byteP
^= 1; /* Reverse branch condition. */
889 p
[2] = VAX_PC_RELATIVE_MODE
;
890 fix_new (frag_now
, p
+ 3 - frag_now
->fr_literal
,
892 this_add_number
, 1, NO_RELOC
);
900 know (operandP
->vop_access
!= 'b'); /* So it is ordinary operand. */
901 know (operandP
->vop_access
!= ' '); /* ' ' target-independent: elsewhere. */
902 know (operandP
->vop_access
== 'a'
903 || operandP
->vop_access
== 'm'
904 || operandP
->vop_access
== 'r'
905 || operandP
->vop_access
== 'v'
906 || operandP
->vop_access
== 'w');
907 if (operandP
->vop_short
== 's')
909 if (to_seg
== SEG_ABSOLUTE
)
911 if (this_add_number
< 0 || this_add_number
>= 64)
913 as_warn ("Short literal overflow(%d.), immediate mode assumed.", this_add_number
);
914 operandP
->vop_short
= 'i';
915 operandP
->vop_mode
= 8;
916 operandP
->vop_reg
= 0xF;
921 as_warn ("Forced short literal to immediate mode. now_seg=%s to_seg=%s",
922 segment_name (now_seg
), segment_name (to_seg
));
923 operandP
->vop_short
= 'i';
924 operandP
->vop_mode
= 8;
925 operandP
->vop_reg
= 0xF;
928 if (operandP
->vop_reg
>= 0 && (operandP
->vop_mode
< 8
929 || (operandP
->vop_reg
!= 0xF && operandP
->vop_mode
< 10)))
931 /* One byte operand. */
932 know (operandP
->vop_mode
> 3);
933 FRAG_APPEND_1_CHAR (operandP
->vop_mode
<< 4 | operandP
->vop_reg
);
934 /* All 1-bytes except S^# happen here. */
938 /* {@}{q^}foo{(Rn)} or S^#foo */
939 if (operandP
->vop_reg
== -1 && operandP
->vop_short
!= 's')
942 if (to_seg
== now_seg
)
946 know (operandP
->vop_short
== ' ');
947 p
= frag_var (rs_machine_dependent
, 10, 2,
948 ENCODE_RELAX (STATE_PC_RELATIVE
, STATE_BYTE
),
949 this_add_symbol
, this_add_number
,
951 know (operandP
->vop_mode
== 10 + at
);
953 /* At is the only context we need to carry
954 to other side of relax() process. Must
955 be in the correct bit position of VAX
956 operand spec. byte. */
961 know (operandP
->vop_short
!= ' ');
962 p
= frag_more (length
+ 1);
963 p
[0] = 0xF | ((at
+ "?\12\14?\16"[length
]) << 4);
964 fix_new (frag_now
, p
+ 1 - frag_now
->fr_literal
,
965 length
, this_add_symbol
,
966 this_add_number
, 1, NO_RELOC
);
970 { /* to_seg != now_seg */
971 if (this_add_symbol
== NULL
)
973 know (to_seg
== SEG_ABSOLUTE
);
974 /* Do @#foo: simpler relocation than foo-.(pc) anyway. */
976 p
[0] = VAX_ABSOLUTE_MODE
; /* @#... */
977 md_number_to_chars (p
+ 1, this_add_number
, 4);
978 if (length
&& length
!= 4)
980 as_warn ("Length specification ignored. Address mode 9F used");
985 /* {@}{q^}other_seg */
986 know ((length
== 0 && operandP
->vop_short
== ' ')
987 || (length
> 0 && operandP
->vop_short
!= ' '));
991 * We have a SEG_UNKNOWN symbol. It might
992 * turn out to be in the same segment as
993 * the instruction, permitting relaxation.
995 p
= frag_var (rs_machine_dependent
, 5, 2,
996 ENCODE_RELAX (STATE_PC_RELATIVE
, STATE_UNDF
),
997 this_add_symbol
, this_add_number
,
1005 know (operandP
->vop_short
== ' ');
1006 length
= 4; /* Longest possible. */
1008 p
= frag_more (length
+ 1);
1009 p
[0] = 0xF | ((at
+ "?\12\14?\16"[length
]) << 4);
1010 md_number_to_chars (p
+ 1, this_add_number
, length
);
1012 p
+ 1 - frag_now
->fr_literal
,
1013 length
, this_add_symbol
,
1014 this_add_number
, 1, NO_RELOC
);
1021 /* {@}{q^}foo(Rn) or S^# or I^# or # */
1022 if (operandP
->vop_mode
< 0xA)
1024 /* # or S^# or I^# */
1026 && to_seg
== SEG_ABSOLUTE
1027 && operandP
->vop_mode
== 8 /* No '@'. */
1028 && this_add_number
< 64
1029 && this_add_number
>= 0)
1031 operandP
->vop_short
= 's';
1033 if (operandP
->vop_short
== 's')
1035 FRAG_APPEND_1_CHAR (this_add_number
);
1041 p
= frag_more (nbytes
+ 1);
1042 know (operandP
->vop_reg
== 0xF);
1043 p
[0] = (operandP
->vop_mode
<< 4) | 0xF;
1044 if (to_seg
== SEG_ABSOLUTE
)
1047 * If nbytes > 4, then we are scrod. We
1048 * don't know if the high order bytes
1049 * are to be 0xFF or 0x00. BSD4.2 & RMS
1050 * say use 0x00. OK --- but this
1051 * assembler needs ANOTHER rewrite to
1052 * cope properly with this bug. */
1053 md_number_to_chars (p
+ 1, this_add_number
, min (4, nbytes
));
1056 memset (p
+ 5, '\0', nbytes
- 4);
1061 if (expP
->X_op
== O_big
)
1064 * Problem here is to get the bytes
1065 * in the right order. We stored
1066 * our constant as LITTLENUMs, not
1078 for (p
++; nbytes
; nbytes
-= 2, p
+= 2, lP
++)
1080 md_number_to_chars (p
, *lP
, 2);
1086 fix_new (frag_now
, p
+ 1 - frag_now
->fr_literal
,
1087 nbytes
, this_add_symbol
,
1088 this_add_number
, 0, NO_RELOC
);
1094 { /* {@}{q^}foo(Rn) */
1095 know ((length
== 0 && operandP
->vop_short
== ' ')
1096 || (length
> 0 && operandP
->vop_short
!= ' '));
1099 if (to_seg
== SEG_ABSOLUTE
)
1103 test
= this_add_number
;
1108 length
= test
& 0xffff8000 ? 4
1109 : test
& 0xffffff80 ? 2
1117 p
= frag_more (1 + length
);
1118 know (operandP
->vop_reg
>= 0);
1119 p
[0] = operandP
->vop_reg
1120 | ((at
| "?\12\14?\16"[length
]) << 4);
1121 if (to_seg
== SEG_ABSOLUTE
)
1123 md_number_to_chars (p
+ 1, this_add_number
, length
);
1127 fix_new (frag_now
, p
+ 1 - frag_now
->fr_literal
,
1128 length
, this_add_symbol
,
1129 this_add_number
, 0, NO_RELOC
);
1133 } /* if(single-byte-operand) */
1135 } /* for(operandP) */
1136 } /* vax_assemble() */
1139 * md_estimate_size_before_relax()
1141 * Called just before relax().
1142 * Any symbol that is now undefined will not become defined.
1143 * Return the correct fr_subtype in the frag.
1144 * Return the initial "guess for fr_var" to caller.
1145 * The guess for fr_var is ACTUALLY the growth beyond fr_fix.
1146 * Whatever we do to grow fr_fix or fr_var contributes to our returned value.
1147 * Although it may not be explicit in the frag, pretend fr_var starts with a
1151 md_estimate_size_before_relax (fragP
, segment
)
1158 old_fr_fix
= fragP
->fr_fix
;
1159 switch (fragP
->fr_subtype
)
1161 case ENCODE_RELAX (STATE_PC_RELATIVE
, STATE_UNDF
):
1162 if (S_GET_SEGMENT (fragP
->fr_symbol
) == segment
)
1163 { /* A relaxable case. */
1164 fragP
->fr_subtype
= ENCODE_RELAX (STATE_PC_RELATIVE
, STATE_BYTE
);
1168 p
= fragP
->fr_literal
+ old_fr_fix
;
1169 p
[0] |= VAX_PC_RELATIVE_MODE
; /* Preserve @ bit. */
1170 fragP
->fr_fix
+= 1 + 4;
1171 fix_new (fragP
, old_fr_fix
+ 1, 4, fragP
->fr_symbol
,
1172 fragP
->fr_offset
, 1, NO_RELOC
);
1177 case ENCODE_RELAX (STATE_CONDITIONAL_BRANCH
, STATE_UNDF
):
1178 if (S_GET_SEGMENT (fragP
->fr_symbol
) == segment
)
1180 fragP
->fr_subtype
= ENCODE_RELAX (STATE_CONDITIONAL_BRANCH
, STATE_BYTE
);
1184 p
= fragP
->fr_literal
+ old_fr_fix
;
1185 *fragP
->fr_opcode
^= 1; /* Reverse sense of branch. */
1188 p
[2] = VAX_PC_RELATIVE_MODE
; /* ...(PC) */
1189 fragP
->fr_fix
+= 1 + 1 + 1 + 4;
1190 fix_new (fragP
, old_fr_fix
+ 3, 4, fragP
->fr_symbol
,
1191 fragP
->fr_offset
, 1, NO_RELOC
);
1196 case ENCODE_RELAX (STATE_COMPLEX_BRANCH
, STATE_UNDF
):
1197 if (S_GET_SEGMENT (fragP
->fr_symbol
) == segment
)
1199 fragP
->fr_subtype
= ENCODE_RELAX (STATE_COMPLEX_BRANCH
, STATE_WORD
);
1203 p
= fragP
->fr_literal
+ old_fr_fix
;
1209 p
[5] = VAX_PC_RELATIVE_MODE
; /* ...(pc) */
1210 fragP
->fr_fix
+= 2 + 2 + 1 + 1 + 4;
1211 fix_new (fragP
, old_fr_fix
+ 6, 4, fragP
->fr_symbol
,
1212 fragP
->fr_offset
, 1, NO_RELOC
);
1217 case ENCODE_RELAX (STATE_COMPLEX_HOP
, STATE_UNDF
):
1218 if (S_GET_SEGMENT (fragP
->fr_symbol
) == segment
)
1220 fragP
->fr_subtype
= ENCODE_RELAX (STATE_COMPLEX_HOP
, STATE_BYTE
);
1224 p
= fragP
->fr_literal
+ old_fr_fix
;
1229 p
[4] = VAX_PC_RELATIVE_MODE
; /* ...(pc) */
1230 fragP
->fr_fix
+= 1 + 2 + 1 + 1 + 4;
1231 fix_new (fragP
, old_fr_fix
+ 5, 4, fragP
->fr_symbol
,
1232 fragP
->fr_offset
, 1, NO_RELOC
);
1237 case ENCODE_RELAX (STATE_ALWAYS_BRANCH
, STATE_UNDF
):
1238 if (S_GET_SEGMENT (fragP
->fr_symbol
) == segment
)
1240 fragP
->fr_subtype
= ENCODE_RELAX (STATE_ALWAYS_BRANCH
, STATE_BYTE
);
1244 p
= fragP
->fr_literal
+ old_fr_fix
;
1245 *fragP
->fr_opcode
+= VAX_WIDEN_LONG
;
1246 p
[0] = VAX_PC_RELATIVE_MODE
; /* ...(PC) */
1247 fragP
->fr_fix
+= 1 + 4;
1248 fix_new (fragP
, old_fr_fix
+ 1, 4, fragP
->fr_symbol
,
1249 fragP
->fr_offset
, 1, NO_RELOC
);
1257 return (fragP
->fr_var
+ fragP
->fr_fix
- old_fr_fix
);
1258 } /* md_estimate_size_before_relax() */
1261 * md_convert_frag();
1263 * Called after relax() is finished.
1264 * In: Address of frag.
1265 * fr_type == rs_machine_dependent.
1266 * fr_subtype is what the address relaxed to.
1268 * Out: Any fixSs and constants are set up.
1269 * Caller will turn frag into a ".space 0".
1272 md_convert_frag (headers
, fragP
)
1273 object_headers
*headers
;
1276 char *addressP
; /* -> _var to change. */
1277 char *opcodeP
; /* -> opcode char(s) to change. */
1278 short int length_code
; /* 2=long 1=word 0=byte */
1279 short int extension
= 0; /* Size of relaxed address. */
1280 /* Added to fr_fix: incl. ALL var chars. */
1283 long address_of_var
;
1284 /* Where, in file space, is _var of *fragP? */
1285 long target_address
= 0;
1286 /* Where, in file space, does addr point? */
1288 know (fragP
->fr_type
== rs_machine_dependent
);
1289 length_code
= fragP
->fr_subtype
& 3; /* depends on ENCODE_RELAX() */
1290 know (length_code
>= 0 && length_code
< 3);
1291 where
= fragP
->fr_fix
;
1292 addressP
= fragP
->fr_literal
+ where
;
1293 opcodeP
= fragP
->fr_opcode
;
1294 symbolP
= fragP
->fr_symbol
;
1296 target_address
= S_GET_VALUE (symbolP
) + fragP
->fr_offset
;
1297 address_of_var
= fragP
->fr_address
+ where
;
1299 switch (fragP
->fr_subtype
)
1302 case ENCODE_RELAX (STATE_PC_RELATIVE
, STATE_BYTE
):
1303 know (*addressP
== 0 || *addressP
== 0x10); /* '@' bit. */
1304 addressP
[0] |= 0xAF; /* Byte displacement. */
1305 addressP
[1] = target_address
- (address_of_var
+ 2);
1309 case ENCODE_RELAX (STATE_PC_RELATIVE
, STATE_WORD
):
1310 know (*addressP
== 0 || *addressP
== 0x10); /* '@' bit. */
1311 addressP
[0] |= 0xCF; /* Word displacement. */
1312 md_number_to_chars (addressP
+ 1, target_address
- (address_of_var
+ 3), 2);
1316 case ENCODE_RELAX (STATE_PC_RELATIVE
, STATE_LONG
):
1317 know (*addressP
== 0 || *addressP
== 0x10); /* '@' bit. */
1318 addressP
[0] |= 0xEF; /* Long word displacement. */
1319 md_number_to_chars (addressP
+ 1, target_address
- (address_of_var
+ 5), 4);
1323 case ENCODE_RELAX (STATE_CONDITIONAL_BRANCH
, STATE_BYTE
):
1324 addressP
[0] = target_address
- (address_of_var
+ 1);
1328 case ENCODE_RELAX (STATE_CONDITIONAL_BRANCH
, STATE_WORD
):
1329 opcodeP
[0] ^= 1; /* Reverse sense of test. */
1331 addressP
[1] = VAX_BRB
+ VAX_WIDEN_WORD
;
1332 md_number_to_chars (addressP
+ 2, target_address
- (address_of_var
+ 4), 2);
1336 case ENCODE_RELAX (STATE_CONDITIONAL_BRANCH
, STATE_LONG
):
1337 opcodeP
[0] ^= 1; /* Reverse sense of test. */
1339 addressP
[1] = VAX_JMP
;
1340 addressP
[2] = VAX_PC_RELATIVE_MODE
;
1341 md_number_to_chars (addressP
+ 3, target_address
, 4);
1345 case ENCODE_RELAX (STATE_ALWAYS_BRANCH
, STATE_BYTE
):
1346 addressP
[0] = target_address
- (address_of_var
+ 1);
1350 case ENCODE_RELAX (STATE_ALWAYS_BRANCH
, STATE_WORD
):
1351 opcodeP
[0] += VAX_WIDEN_WORD
; /* brb -> brw, bsbb -> bsbw */
1352 md_number_to_chars (addressP
, target_address
- (address_of_var
+ 2), 2);
1356 case ENCODE_RELAX (STATE_ALWAYS_BRANCH
, STATE_LONG
):
1357 opcodeP
[0] += VAX_WIDEN_LONG
; /* brb -> jmp, bsbb -> jsb */
1358 addressP
[0] = VAX_PC_RELATIVE_MODE
;
1359 md_number_to_chars (addressP
+ 1, target_address
- (address_of_var
+ 5), 4);
1363 case ENCODE_RELAX (STATE_COMPLEX_BRANCH
, STATE_WORD
):
1364 md_number_to_chars (addressP
, target_address
- (address_of_var
+ 2), 2);
1368 case ENCODE_RELAX (STATE_COMPLEX_BRANCH
, STATE_LONG
):
1371 addressP
[2] = VAX_BRB
;
1373 addressP
[4] = VAX_JMP
;
1374 addressP
[5] = VAX_PC_RELATIVE_MODE
;
1375 md_number_to_chars (addressP
+ 6, target_address
, 4);
1379 case ENCODE_RELAX (STATE_COMPLEX_HOP
, STATE_BYTE
):
1380 addressP
[0] = target_address
- (address_of_var
+ 1);
1384 case ENCODE_RELAX (STATE_COMPLEX_HOP
, STATE_WORD
):
1386 addressP
[1] = VAX_BRB
;
1388 addressP
[3] = VAX_BRW
;
1389 md_number_to_chars (addressP
+ 4, target_address
- (address_of_var
+ 6), 2);
1393 case ENCODE_RELAX (STATE_COMPLEX_HOP
, STATE_LONG
):
1395 addressP
[1] = VAX_BRB
;
1397 addressP
[3] = VAX_JMP
;
1398 addressP
[4] = VAX_PC_RELATIVE_MODE
;
1399 md_number_to_chars (addressP
+ 5, target_address
, 4);
1404 BAD_CASE (fragP
->fr_subtype
);
1407 fragP
->fr_fix
+= extension
;
1408 } /* md_convert_frag() */
1410 /* Translate internal format of relocation info into target format.
1412 On vax: first 4 bytes are normal unsigned long, next three bytes
1413 are symbolnum, least sig. byte first. Last byte is broken up with
1414 the upper nibble as nuthin, bit 3 as extern, bits 2 & 1 as length, and
1418 md_ri_to_chars (the_bytes
, ri
)
1420 struct reloc_info_generic ri
;
1423 md_number_to_chars (the_bytes
, ri
.r_address
, sizeof (ri
.r_address
));
1424 /* now the fun stuff */
1425 the_bytes
[6] = (ri
.r_symbolnum
>> 16) & 0x0ff;
1426 the_bytes
[5] = (ri
.r_symbolnum
>> 8) & 0x0ff;
1427 the_bytes
[4] = ri
.r_symbolnum
& 0x0ff;
1428 the_bytes
[7] = (((ri
.r_extern
<< 3) & 0x08) | ((ri
.r_length
<< 1) & 0x06) |
1429 ((ri
.r_pcrel
<< 0) & 0x01)) & 0x0F;
1432 #endif /* comment */
1435 tc_aout_fix_to_chars (where
, fixP
, segment_address_in_file
)
1438 relax_addressT segment_address_in_file
;
1441 * In: length of relocation (or of address) in chars: 1, 2 or 4.
1442 * Out: GNU LD relocation length code: 0, 1, or 2.
1445 static const unsigned char nbytes_r_length
[] = {42, 0, 1, 42, 2};
1448 know (fixP
->fx_addsy
!= NULL
);
1450 md_number_to_chars (where
,
1451 fixP
->fx_frag
->fr_address
+ fixP
->fx_where
- segment_address_in_file
,
1454 r_symbolnum
= (S_IS_DEFINED (fixP
->fx_addsy
)
1455 ? S_GET_TYPE (fixP
->fx_addsy
)
1456 : fixP
->fx_addsy
->sy_number
);
1458 where
[6] = (r_symbolnum
>> 16) & 0x0ff;
1459 where
[5] = (r_symbolnum
>> 8) & 0x0ff;
1460 where
[4] = r_symbolnum
& 0x0ff;
1461 where
[7] = ((((!S_IS_DEFINED (fixP
->fx_addsy
)) << 3) & 0x08)
1462 | ((nbytes_r_length
[fixP
->fx_size
] << 1) & 0x06)
1463 | (((fixP
->fx_pcrel
<< 0) & 0x01) & 0x0f));
1467 * BUGS, GRIPES, APOLOGIA, etc.
1469 * The opcode table 'votstrs' needs to be sorted on opcode frequency.
1470 * That is, AFTER we hash it with hash_...(), we want most-used opcodes
1471 * to come out of the hash table faster.
1473 * I am sorry to inflict yet another VAX assembler on the world, but
1474 * RMS says we must do everything from scratch, to prevent pin-heads
1475 * restricting this software.
1479 * This is a vaguely modular set of routines in C to parse VAX
1480 * assembly code using DEC mnemonics. It is NOT un*x specific.
1482 * The idea here is that the assembler has taken care of all:
1489 * condensing any whitespace down to exactly one space
1490 * and all we have to do is parse 1 line into a vax instruction
1491 * partially formed. We will accept a line, and deliver:
1492 * an error message (hopefully empty)
1493 * a skeleton VAX instruction (tree structure)
1494 * textual pointers to all the operand expressions
1495 * a warning message that notes a silly operand (hopefully empty)
1499 * E D I T H I S T O R Y
1501 * 17may86 Dean Elsner. Bug if line ends immediately after opcode.
1502 * 30apr86 Dean Elsner. New vip_op() uses arg block so change call.
1503 * 6jan86 Dean Elsner. Crock vip_begin() to call vip_op_defaults().
1504 * 2jan86 Dean Elsner. Invent synthetic opcodes.
1505 * Widen vax_opcodeT to 32 bits. Use a bit for VIT_OPCODE_SYNTHETIC,
1506 * which means this is not a real opcode, it is like a macro; it will
1507 * be relax()ed into 1 or more instructions.
1508 * Use another bit for VIT_OPCODE_SPECIAL if the op-code is not optimised
1509 * like a regular branch instruction. Option added to vip_begin():
1510 * exclude synthetic opcodes. Invent synthetic_votstrs[].
1511 * 31dec85 Dean Elsner. Invent vit_opcode_nbytes.
1512 * Also make vit_opcode into a char[]. We now have n-byte vax opcodes,
1513 * so caller's don't have to know the difference between a 1-byte & a
1514 * 2-byte op-code. Still need vax_opcodeT concept, so we know how
1515 * big an object must be to hold an op.code.
1516 * 30dec85 Dean Elsner. Widen typedef vax_opcodeT in "vax-inst.h"
1517 * because vax opcodes may be 16 bits. Our crufty C compiler was
1518 * happily initialising 8-bit vot_codes with 16-bit numbers!
1519 * (Wouldn't the 'phone company like to compress data so easily!)
1520 * 29dec85 Dean Elsner. New static table vax_operand_width_size[].
1521 * Invented so we know hw many bytes a "I^#42" needs in its immediate
1522 * operand. Revised struct vop in "vax-inst.h": explicitly include
1523 * byte length of each operand, and it's letter-code datum type.
1524 * 17nov85 Dean Elsner. Name Change.
1525 * Due to ar(1) truncating names, we learned the hard way that
1526 * "vax-inst-parse.c" -> "vax-inst-parse." dropping the "o" off
1527 * the archived object name. SO... we shortened the name of this
1528 * source file, and changed the makefile.
1531 /* handle of the OPCODE hash table */
1532 static struct hash_control
*op_hash
;
1535 * In: 1 character, from "bdfghloqpw" being the data-type of an operand
1536 * of a vax instruction.
1538 * Out: the length of an operand of that type, in bytes.
1539 * Special branch operands types "-?!" have length 0.
1542 static const short int vax_operand_width_size
[256] =
1546 _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
,
1547 _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
,
1548 _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
,
1549 _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
,
1550 _
, _
, 1, _
, 8, _
, 4, 8, 16, _
, _
, _
, 4, _
, _
, 16, /* ..b.d.fgh...l..o */
1551 _
, 8, _
, _
, _
, _
, _
, 2, _
, _
, _
, _
, _
, _
, _
, _
, /* .q.....w........ */
1552 _
, _
, 1, _
, 8, _
, 4, 8, 16, _
, _
, _
, 4, _
, _
, 16, /* ..b.d.fgh...l..o */
1553 _
, 8, _
, _
, _
, _
, _
, 2, _
, _
, _
, _
, _
, _
, _
, _
, /* .q.....w........ */
1554 _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
,
1555 _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
,
1556 _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
,
1557 _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
,
1558 _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
,
1559 _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
,
1560 _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
,
1561 _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
, _
};
1565 * This perversion encodes all the vax opcodes as a bunch of strings.
1566 * RMS says we should build our hash-table at run-time. Hmm.
1567 * Please would someone arrange these in decreasing frequency of opcode?
1568 * Because of the way hash_...() works, the most frequently used opcode
1569 * should be textually first and so on.
1571 * Input for this table was 'vax.opcodes', awk(1)ed by 'vax.opcodes.c.awk' .
1572 * So change 'vax.opcodes', then re-generate this table.
1575 #include "opcode/vax.h"
1578 * This is a table of optional op-codes. All of them represent
1579 * 'synthetic' instructions that seem popular.
1581 * Here we make some pseudo op-codes. Every code has a bit set to say
1582 * it is synthetic. This lets you catch them if you want to
1583 * ban these opcodes. They are mnemonics for "elastic" instructions
1584 * that are supposed to assemble into the fewest bytes needed to do a
1585 * branch, or to do a conditional branch, or whatever.
1587 * The opcode is in the usual place [low-order n*8 bits]. This means
1588 * that if you mask off the bucky bits, the usual rules apply about
1589 * how long the opcode is.
1591 * All VAX branch displacements come at the end of the instruction.
1592 * For simple branches (1-byte opcode + 1-byte displacement) the last
1593 * operand is coded 'b?' where the "data type" '?' is a clue that we
1594 * may reverse the sense of the branch (complement lowest order bit)
1595 * and branch around a jump. This is by far the most common case.
1596 * That is why the VIT_OPCODE_SYNTHETIC bit is set: it says this is
1597 * a 0-byte op-code followed by 2 or more bytes of operand address.
1599 * If the op-code has VIT_OPCODE_SPECIAL set, then we have a more unusual
1602 * For JBSB & JBR the treatment is the similar, except (1) we have a 'bw'
1603 * option before (2) we can directly JSB/JMP because there is no condition.
1604 * These operands have 'b-' as their access/data type.
1606 * That leaves a bunch of random opcodes: JACBx, JxOBxxx. In these
1607 * cases, we do the same idea. JACBxxx are all marked with a 'b!'
1608 * JAOBxxx & JSOBxxx are marked with a 'b:'.
1611 #if (VIT_OPCODE_SYNTHETIC != 0x80000000)
1612 You have just broken the encoding below
, which assumes the sign bit
1613 means
'I am an imaginary instruction'.
1616 #if (VIT_OPCODE_SPECIAL != 0x40000000)
1617 You have just broken the encoding below
, which assumes the
0x40 M bit means
1618 'I am not to be "optimised" the way normal branches are'.
1621 static const struct vot
1622 synthetic_votstrs
[] =
1624 {"jbsb", {"b-", 0xC0000010}}, /* BSD 4.2 */
1625 /* jsb used already */
1626 {"jbr", {"b-", 0xC0000011}}, /* BSD 4.2 */
1627 {"jr", {"b-", 0xC0000011}}, /* consistent */
1628 {"jneq", {"b?", 0x80000012}},
1629 {"jnequ", {"b?", 0x80000012}},
1630 {"jeql", {"b?", 0x80000013}},
1631 {"jeqlu", {"b?", 0x80000013}},
1632 {"jgtr", {"b?", 0x80000014}},
1633 {"jleq", {"b?", 0x80000015}},
1634 /* un-used opcodes here */
1635 {"jgeq", {"b?", 0x80000018}},
1636 {"jlss", {"b?", 0x80000019}},
1637 {"jgtru", {"b?", 0x8000001a}},
1638 {"jlequ", {"b?", 0x8000001b}},
1639 {"jvc", {"b?", 0x8000001c}},
1640 {"jvs", {"b?", 0x8000001d}},
1641 {"jgequ", {"b?", 0x8000001e}},
1642 {"jcc", {"b?", 0x8000001e}},
1643 {"jlssu", {"b?", 0x8000001f}},
1644 {"jcs", {"b?", 0x8000001f}},
1646 {"jacbw", {"rwrwmwb!", 0xC000003d}},
1647 {"jacbf", {"rfrfmfb!", 0xC000004f}},
1648 {"jacbd", {"rdrdmdb!", 0xC000006f}},
1649 {"jacbb", {"rbrbmbb!", 0xC000009d}},
1650 {"jacbl", {"rlrlmlb!", 0xC00000f1}},
1651 {"jacbg", {"rgrgmgb!", 0xC0004ffd}},
1652 {"jacbh", {"rhrhmhb!", 0xC0006ffd}},
1654 {"jbs", {"rlvbb?", 0x800000e0}},
1655 {"jbc", {"rlvbb?", 0x800000e1}},
1656 {"jbss", {"rlvbb?", 0x800000e2}},
1657 {"jbcs", {"rlvbb?", 0x800000e3}},
1658 {"jbsc", {"rlvbb?", 0x800000e4}},
1659 {"jbcc", {"rlvbb?", 0x800000e5}},
1660 {"jbssi", {"rlvbb?", 0x800000e6}},
1661 {"jbcci", {"rlvbb?", 0x800000e7}},
1662 {"jlbs", {"rlb?", 0x800000e8}},
1663 {"jlbc", {"rlb?", 0x800000e9}},
1665 {"jaoblss", {"rlmlb:", 0xC00000f2}},
1666 {"jaobleq", {"rlmlb:", 0xC00000f3}},
1667 {"jsobgeq", {"mlb:", 0xC00000f4}},
1668 {"jsobgtr", {"mlb:", 0xC00000f5}},
1670 /* CASEx has no branch addresses in our conception of it. */
1671 /* You should use ".word ..." statements after the "case ...". */
1673 {"", ""} /* empty is end sentinel */
1675 }; /* synthetic_votstrs */
1678 * v i p _ b e g i n ( )
1680 * Call me once before you decode any lines.
1681 * I decode votstrs into a hash table at op_hash (which I create).
1682 * I return an error text or null.
1683 * If you want, I will include the 'synthetic' jXXX instructions in the
1684 * instruction table.
1685 * You must nominate metacharacters for eg DEC's "#", "@", "^".
1689 vip_begin (synthetic_too
, immediate
, indirect
, displen
)
1690 int synthetic_too
; /* 1 means include jXXX op-codes. */
1691 char *immediate
, *indirect
, *displen
;
1693 const struct vot
*vP
; /* scan votstrs */
1694 const char *retval
= 0; /* error text */
1696 op_hash
= hash_new ();
1698 for (vP
= votstrs
; *vP
->vot_name
&& !retval
; vP
++)
1699 retval
= hash_insert (op_hash
, vP
->vot_name
, (PTR
) &vP
->vot_detail
);
1702 for (vP
= synthetic_votstrs
; *vP
->vot_name
&& !retval
; vP
++)
1703 retval
= hash_insert (op_hash
, vP
->vot_name
, (PTR
) &vP
->vot_detail
);
1706 vip_op_defaults (immediate
, indirect
, displen
);
1716 * This converts a string into a vax instruction.
1717 * The string must be a bare single instruction in dec-vax (with BSD4 frobs)
1719 * It provides some error messages: at most one fatal error message (which
1720 * stops the scan) and at most one warning message for each operand.
1721 * The vax instruction is returned in exploded form, since we have no
1722 * knowledge of how you parse (or evaluate) your expressions.
1723 * We do however strip off and decode addressing modes and operation
1726 * The exploded instruction is returned to a struct vit of your choice.
1727 * #include "vax-inst.h" to know what a struct vit is.
1729 * This function's value is a string. If it is not "" then an internal
1730 * logic error was found: read this code to assign meaning to the string.
1731 * No argument string should generate such an error string:
1732 * it means a bug in our code, not in the user's text.
1734 * You MUST have called vip_begin() once before using this function.
1738 vip (vitP
, instring
)
1739 struct vit
*vitP
; /* We build an exploded instruction here. */
1740 char *instring
; /* Text of a vax instruction: we modify. */
1742 /* How to bit-encode this opcode. */
1743 struct vot_wot
*vwP
;
1744 /* 1/skip whitespace.2/scan vot_how */
1747 /* counts number of operands seen */
1748 unsigned char count
;
1749 /* scan operands in struct vit */
1750 struct vop
*operandp
;
1751 /* error over all operands */
1753 /* Remember char, (we clobber it with '\0' temporarily). */
1755 /* Op-code of this instruction. */
1758 if (*instring
== ' ')
1759 ++instring
; /* Skip leading whitespace. */
1760 for (p
= instring
; *p
&& *p
!= ' '; p
++);; /* MUST end in end-of-string or exactly 1 space. */
1761 /* Scanned up to end of operation-code. */
1762 /* Operation-code is ended with whitespace. */
1763 if (p
- instring
== 0)
1765 vitP
->vit_error
= "No operator";
1767 memset (vitP
->vit_opcode
, '\0', sizeof (vitP
->vit_opcode
));
1774 * Here with instring pointing to what better be an op-name, and p
1775 * pointing to character just past that.
1776 * We trust instring points to an op-name, with no whitespace.
1778 vwP
= (struct vot_wot
*) hash_find (op_hash
, instring
);
1779 *p
= c
; /* Restore char after op-code. */
1782 vitP
->vit_error
= "Unknown operator";
1784 memset (vitP
->vit_opcode
, '\0', sizeof (vitP
->vit_opcode
));
1789 * We found a match! So lets pick up as many operands as the
1790 * instruction wants, and even gripe if there are too many.
1791 * We expect comma to seperate each operand.
1792 * We let instring track the text, while p tracks a part of the
1796 * The lines below know about 2-byte opcodes starting FD,FE or FF.
1797 * They also understand synthetic opcodes. Note:
1798 * we return 32 bits of opcode, including bucky bits, BUT
1799 * an opcode length is either 8 or 16 bits for vit_opcode_nbytes.
1801 oc
= vwP
->vot_code
; /* The op-code. */
1802 vitP
->vit_opcode_nbytes
= (oc
& 0xFF) >= 0xFD ? 2 : 1;
1803 md_number_to_chars (vitP
->vit_opcode
, oc
, 4);
1804 count
= 0; /* no operands seen yet */
1805 instring
= p
; /* point just past operation code */
1807 for (p
= vwP
->vot_how
, operandp
= vitP
->vit_operand
;
1808 !(alloperr
&& *alloperr
) && *p
;
1812 * Here to parse one operand. Leave instring pointing just
1813 * past any one ',' that marks the end of this operand.
1816 as_fatal ("odd number of bytes in operand description");
1819 for (q
= instring
; (c
= *q
) && c
!= ','; q
++)
1822 * Q points to ',' or '\0' that ends argument. C is that
1826 operandp
->vop_width
= p
[1];
1827 operandp
->vop_nbytes
= vax_operand_width_size
[p
[1]];
1828 operandp
->vop_access
= p
[0];
1829 vip_op (instring
, operandp
);
1830 *q
= c
; /* Restore input text. */
1831 if (operandp
->vop_error
)
1832 alloperr
= "Bad operand";
1833 instring
= q
+ (c
? 1 : 0); /* next operand (if any) */
1834 count
++; /* won another argument, may have an operr */
1837 alloperr
= "Not enough operands";
1841 if (*instring
== ' ')
1842 instring
++; /* Skip whitespace. */
1844 alloperr
= "Too many operands";
1846 vitP
->vit_error
= alloperr
;
1849 vitP
->vit_operands
= count
;
1855 * Test program for above.
1858 struct vit myvit
; /* build an exploded vax instruction here */
1859 char answer
[100]; /* human types a line of vax assembler here */
1860 char *mybug
; /* "" or an internal logic diagnostic */
1861 int mycount
; /* number of operands */
1862 struct vop
*myvop
; /* scan operands from myvit */
1863 int mysynth
; /* 1 means want synthetic opcodes. */
1864 char my_immediate
[200];
1865 char my_indirect
[200];
1866 char my_displen
[200];
1872 printf ("0 means no synthetic instructions. ");
1873 printf ("Value for vip_begin? ");
1875 sscanf (answer
, "%d", &mysynth
);
1876 printf ("Synthetic opcodes %s be included.\n", mysynth
? "will" : "will not");
1877 printf ("enter immediate symbols eg enter # ");
1878 gets (my_immediate
);
1879 printf ("enter indirect symbols eg enter @ ");
1881 printf ("enter displen symbols eg enter ^ ");
1883 if (p
= vip_begin (mysynth
, my_immediate
, my_indirect
, my_displen
))
1885 error ("vip_begin=%s", p
);
1887 printf ("An empty input line will quit you from the vax instruction parser\n");
1890 printf ("vax instruction: ");
1895 break; /* out of for each input text loop */
1897 vip (&myvit
, answer
);
1898 if (*myvit
.vit_error
)
1900 printf ("ERR:\"%s\"\n", myvit
.vit_error
);
1903 for (mycount
= myvit
.vit_opcode_nbytes
, p
= myvit
.vit_opcode
;
1908 printf ("%02x ", *p
& 0xFF);
1910 printf (" operand count=%d.\n", mycount
= myvit
.vit_operands
);
1911 for (myvop
= myvit
.vit_operand
; mycount
; mycount
--, myvop
++)
1913 printf ("mode=%xx reg=%xx ndx=%xx len='%c'=%c%c%d. expr=\"",
1914 myvop
->vop_mode
, myvop
->vop_reg
, myvop
->vop_ndx
,
1915 myvop
->vop_short
, myvop
->vop_access
, myvop
->vop_width
,
1917 for (p
= myvop
->vop_expr_begin
; p
<= myvop
->vop_expr_end
; p
++)
1922 if (myvop
->vop_error
)
1924 printf (" err:\"%s\"\n", myvop
->vop_error
);
1926 if (myvop
->vop_warn
)
1928 printf (" wrn:\"%s\"\n", myvop
->vop_warn
);
1936 #endif /* #ifdef test */
1938 /* end of vax_ins_parse.c */
1940 /* vax_reg_parse.c - convert a VAX register name to a number */
1942 /* Copyright (C) 1987 Free Software Foundation, Inc. A part of GNU. */
1945 * v a x _ r e g _ p a r s e ( )
1947 * Take 3 char.s, the last of which may be `\0` (non-existent)
1948 * and return the VAX register number that they represent.
1950 * Return -1 if they don't form a register name. Good names return
1951 * a number from 0:15 inclusive.
1953 * Case is not important in a name.
1955 * Register names understood are:
1982 int /* return -1 or 0:15 */
1983 vax_reg_parse (c1
, c2
, c3
) /* 3 chars of register name */
1984 char c1
, c2
, c3
; /* c3 == 0 if 2-character reg name */
1986 int retval
; /* return -1:15 */
1994 if (isdigit (c2
) && c1
== 'r')
1999 retval
= retval
* 10 + c3
- '0';
2000 retval
= (retval
> 15) ? -1 : retval
;
2001 /* clamp the register value to 1 hex digit */
2004 retval
= -1; /* c3 must be '\0' or a digit */
2006 else if (c3
) /* There are no three letter regs */
2025 else if (c1
== 'p' && c2
== 'c')
2035 * Parse a vax operand in DEC assembler notation.
2036 * For speed, expect a string of whitespace to be reduced to a single ' '.
2037 * This is the case for GNU AS, and is easy for other DEC-compatible
2040 * Knowledge about DEC VAX assembler operand notation lives here.
2041 * This doesn't even know what a register name is, except it believes
2042 * all register names are 2 or 3 characters, and lets vax_reg_parse() say
2043 * what number each name represents.
2044 * It does, however, know that PC, SP etc are special registers so it can
2045 * detect addressing modes that are silly for those registers.
2047 * Where possible, it delivers 1 fatal or 1 warning message if the operand
2048 * is suspect. Exactly what we test for is still evolving.
2056 * There were a number of 'mismatched argument type' bugs to vip_op.
2057 * The most general solution is to typedef each (of many) arguments.
2058 * We used instead a typedef'd argument block. This is less modular
2059 * than using seperate return pointers for each result, but runs faster
2060 * on most engines, and seems to keep programmers happy. It will have
2061 * to be done properly if we ever want to use vip_op as a general-purpose
2062 * module (it was designed to be).
2066 * Doesn't support DEC "G^" format operands. These always take 5 bytes
2067 * to express, and code as modes 8F or 9F. Reason: "G^" deprives you of
2068 * optimising to (say) a "B^" if you are lucky in the way you link.
2069 * When someone builds a linker smart enough to convert "G^" to "B^", "W^"
2070 * whenever possible, then we should implement it.
2071 * If there is some other use for "G^", feel free to code it in!
2076 * If I nested if()s more, I could avoid testing (*err) which would save
2077 * time, space and page faults. I didn't nest all those if()s for clarity
2078 * and because I think the mode testing can be re-arranged 1st to test the
2079 * commoner constructs 1st. Does anybody have statistics on this?
2085 * In future, we should be able to 'compose' error messages in a scratch area
2086 * and give the user MUCH more informative error messages. Although this takes
2087 * a little more code at run-time, it will make this module much more self-
2088 * documenting. As an example of what sucks now: most error messages have
2089 * hardwired into them the DEC VAX metacharacters "#^@" which are nothing like
2090 * the Un*x characters "$`*", that most users will expect from this AS.
2094 * The input is a string, ending with '\0'.
2096 * We also require a 'hint' of what kind of operand is expected: so
2097 * we can remind caller not to write into literals for instance.
2099 * The output is a skeletal instruction.
2101 * The algorithm has two parts.
2102 * 1. extract the syntactic features (parse off all the @^#-()+[] mode crud);
2103 * 2. express the @^#-()+[] as some parameters suited to further analysis.
2105 * 2nd step is where we detect the googles of possible invalid combinations
2106 * a human (or compiler) might write. Note that if we do a half-way
2107 * decent assembler, we don't know how long to make (eg) displacement
2108 * fields when we first meet them (because they may not have defined values).
2109 * So we must wait until we know how many bits are needed for each address,
2110 * then we can know both length and opcodes of instructions.
2111 * For reason(s) above, we will pass to our caller a 'broken' instruction
2112 * of these major components, from which our caller can generate instructions:
2113 * - displacement length I^ S^ L^ B^ W^ unspecified
2115 * - register R0-R15 or absent
2116 * - index register R0-R15 or absent
2117 * - expression text what we don't parse
2118 * - error text(s) why we couldn't understand the operand
2122 * To decode output of this, test errtxt. If errtxt[0] == '\0', then
2123 * we had no errors that prevented parsing. Also, if we ever report
2124 * an internal bug, errtxt[0] is set non-zero. So one test tells you
2125 * if the other outputs are to be taken seriously.
2130 * Because this module is useful for both VMS and UN*X style assemblers
2131 * and because of the variety of UN*X assemblers we must recognise
2132 * the different conventions for assembler operand notation. For example
2133 * VMS says "#42" for immediate mode, while most UN*X say "$42".
2134 * We permit arbitrary sets of (single) characters to represent the
2135 * 3 concepts that DEC writes '#', '@', '^'.
2138 /* character tests */
2139 #define VIP_IMMEDIATE 01 /* Character is like DEC # */
2140 #define VIP_INDIRECT 02 /* Char is like DEC @ */
2141 #define VIP_DISPLEN 04 /* Char is like DEC ^ */
2143 #define IMMEDIATEP(c) (vip_metacharacters [(c)&0xff]&VIP_IMMEDIATE)
2144 #define INDIRECTP(c) (vip_metacharacters [(c)&0xff]&VIP_INDIRECT)
2145 #define DISPLENP(c) (vip_metacharacters [(c)&0xff]&VIP_DISPLEN)
2147 /* We assume 8 bits per byte. Use vip_op_defaults() to set these up BEFORE we
2151 #if defined(CONST_TABLE)
2153 #define I VIP_IMMEDIATE,
2154 #define S VIP_INDIRECT,
2155 #define D VIP_DISPLEN,
2157 vip_metacharacters
[256] =
2159 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/* ^@ ^A ^B ^C ^D ^E ^F ^G ^H ^I ^J ^K ^L ^M ^N ^O*/
2160 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/* ^P ^Q ^R ^S ^T ^U ^V ^W ^X ^Y ^Z ^[ ^\ ^] ^^ ^_ */
2161 _ _ _ _ I _ _ _ _ _ S _ _ _ _ _
/* sp ! " # $ % & ' ( ) * + , - . / */
2162 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/*0 1 2 3 4 5 6 7 8 9 : ; < = > ?*/
2163 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/*@ A B C D E F G H I J K L M N O*/
2164 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/*P Q R S T U V W X Y Z [ \ ] ^ _*/
2165 D _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/*` a b c d e f g h i j k l m n o*/
2166 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/*p q r s t u v w x y z { | } ~ ^?*/
2168 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
2169 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
2170 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
2171 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
2172 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
2173 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
2174 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
2175 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
2182 static char vip_metacharacters
[256];
2185 vip_op_1 (bit
, syms
)
2192 vip_metacharacters
[t
] |= bit
;
2195 /* Can be called any time. More arguments may appear in future. */
2197 vip_op_defaults (immediate
, indirect
, displen
)
2202 vip_op_1 (VIP_IMMEDIATE
, immediate
);
2203 vip_op_1 (VIP_INDIRECT
, indirect
);
2204 vip_op_1 (VIP_DISPLEN
, displen
);
2211 * Dec defines the semantics of address modes (and values)
2212 * by a two-letter code, explained here.
2214 * letter 1: access type
2216 * a address calculation - no data access, registers forbidden
2217 * b branch displacement
2218 * m read - let go of bus - write back "modify"
2220 * v bit field address: like 'a' but registers are OK
2222 * space no operator (eg ".long foo") [our convention]
2224 * letter 2: data type (i.e. width, alignment)
2227 * d double precision floating point (D format)
2228 * f single precision floating point (F format)
2229 * g G format floating
2230 * h H format floating
2235 * ? simple synthetic branch operand
2236 * - unconditional synthetic JSB/JSR operand
2237 * ! complex synthetic branch operand
2239 * The '-?!' letter 2's are not for external consumption. They are used
2240 * for various assemblers. Generally, all unknown widths are assumed 0.
2241 * We don't limit your choice of width character.
2243 * DEC operands are hard work to parse. For example, '@' as the first
2244 * character means indirect (deferred) mode but elswhere it is a shift
2246 * The long-winded explanation of how this is supposed to work is
2247 * cancelled. Read a DEC vax manual.
2248 * We try hard not to parse anything that MIGHT be part of the expression
2249 * buried in that syntax. For example if we see @...(Rn) we don't check
2250 * for '-' before the '(' because mode @-(Rn) does not exist.
2252 * After parsing we have:
2254 * at 1 if leading '@' (or Un*x '*')
2255 * len takes one value from " bilsw". eg B^ -> 'b'.
2256 * hash 1 if leading '#' (or Un*x '$')
2257 * expr_begin, expr_end the expression we did not parse
2258 * even though we don't interpret it, we make use
2259 * of its presence or absence.
2260 * sign -1: -(Rn) 0: absent +1: (Rn)+
2261 * paren 1 if () are around register
2262 * reg major register number 0:15 -1 means absent
2263 * ndx index register number 0:15 -1 means absent
2265 * Again, I dare not explain it: just trace ALL the code!
2269 vip_op (optext
, vopP
)
2270 /* user's input string e.g.: "@B^foo@bar(AP)[FP]:" */
2272 /* Input fields: vop_access, vop_width.
2273 Output fields: _ndx, _reg, _mode, _short, _warn,
2274 _error _expr_begin, _expr_end, _nbytes.
2275 vop_nbytes : number of bytes in a datum. */
2278 /* track operand text forward */
2280 /* track operand text backward */
2282 /* 1 if leading '@' ('*') seen */
2284 /* one of " bilsw" */
2286 /* 1 if leading '#' ('$') seen */
2290 /* 1 if () surround register */
2292 /* register number, -1:absent */
2294 /* index register number -1:absent */
2296 /* report illegal operand, ""==OK */
2297 /* " " is a FAKE error: means we won */
2298 /* ANY err that begins with ' ' is a fake. */
2299 /* " " is converted to "" before return */
2301 /* warn about weird modes pf address */
2303 /* preserve q in case we backup */
2305 /* build up 4-bit operand mode here */
2306 /* note: index mode is in ndx, this is */
2307 /* the major mode of operand address */
2310 * Notice how we move wrong-arg-type bugs INSIDE this module: if we
2311 * get the types wrong below, we lose at compile time rather than at
2314 char access
; /* vop_access. */
2315 char width
; /* vop_width. */
2317 access
= vopP
->vop_access
;
2318 width
= vopP
->vop_width
;
2319 /* None of our code bugs (yet), no user text errors, no warnings
2325 if (*p
== ' ') /* Expect all whitespace reduced to ' '. */
2326 p
++; /* skip over whitespace */
2328 if (at
= INDIRECTP (*p
))
2329 { /* 1 if *p=='@'(or '*' for Un*x) */
2330 p
++; /* at is determined */
2331 if (*p
== ' ') /* Expect all whitespace reduced to ' '. */
2332 p
++; /* skip over whitespace */
2336 * This code is subtle. It tries to detect all legal (letter)'^'
2337 * but it doesn't waste time explicitly testing for premature '\0' because
2338 * this case is rejected as a mismatch against either (letter) or '^'.
2346 if (DISPLENP (p
[1]) && strchr ("bilws", len
= c
))
2347 p
+= 2; /* skip (letter) '^' */
2348 else /* no (letter) '^' seen */
2349 len
= ' '; /* len is determined */
2352 if (*p
== ' ') /* Expect all whitespace reduced to ' '. */
2353 p
++; /* skip over whitespace */
2355 if (hash
= IMMEDIATEP (*p
)) /* 1 if *p=='#' ('$' for Un*x) */
2356 p
++; /* hash is determined */
2359 * p points to what may be the beginning of an expression.
2360 * We have peeled off the front all that is peelable.
2361 * We know at, len, hash.
2363 * Lets point q at the end of the text and parse that (backwards).
2366 for (q
= p
; *q
; q
++)
2368 q
--; /* now q points at last char of text */
2370 if (*q
== ' ' && q
>= p
) /* Expect all whitespace reduced to ' '. */
2372 /* reverse over whitespace, but don't */
2373 /* run back over *p */
2376 * As a matter of policy here, we look for [Rn], although both Rn and S^#
2377 * forbid [Rn]. This is because it is easy, and because only a sick
2378 * cyborg would have [...] trailing an expression in a VAX-like assembler.
2379 * A meticulous parser would first check for Rn followed by '(' or '['
2380 * and not parse a trailing ']' if it found another. We just ban expressions
2385 while (q
>= p
&& *q
!= '[')
2387 /* either q<p or we got matching '[' */
2389 err
= "no '[' to match ']'";
2393 * Confusers like "[]" will eventually lose with a bad register
2394 * name error. So again we don't need to check for early '\0'.
2397 ndx
= vax_reg_parse (q
[1], q
[2], 0);
2398 else if (q
[4] == ']')
2399 ndx
= vax_reg_parse (q
[1], q
[2], q
[3]);
2403 * Since we saw a ']' we will demand a register name in the [].
2404 * If luser hasn't given us one: be rude.
2407 err
= "bad register in []";
2409 err
= "[PC] index banned";
2411 q
--; /* point q just before "[...]" */
2415 ndx
= -1; /* no ']', so no iNDeX register */
2418 * If err = "..." then we lost: run away.
2419 * Otherwise ndx == -1 if there was no "[...]".
2420 * Otherwise, ndx is index register number, and q points before "[...]".
2423 if (*q
== ' ' && q
>= p
) /* Expect all whitespace reduced to ' '. */
2425 /* reverse over whitespace, but don't */
2426 /* run back over *p */
2429 sign
= 0; /* no ()+ or -() seen yet */
2431 if (q
> p
+ 3 && *q
== '+' && q
[-1] == ')')
2433 sign
= 1; /* we saw a ")+" */
2434 q
--; /* q points to ')' */
2437 if (*q
== ')' && q
> p
+ 2)
2439 paren
= 1; /* assume we have "(...)" */
2440 while (q
>= p
&& *q
!= '(')
2442 /* either q<p or we got matching '(' */
2444 err
= "no '(' to match ')'";
2448 * Confusers like "()" will eventually lose with a bad register
2449 * name error. So again we don't need to check for early '\0'.
2452 reg
= vax_reg_parse (q
[1], q
[2], 0);
2453 else if (q
[4] == ')')
2454 reg
= vax_reg_parse (q
[1], q
[2], q
[3]);
2458 * Since we saw a ')' we will demand a register name in the ')'.
2459 * This is nasty: why can't our hypothetical assembler permit
2460 * parenthesised expressions? BECAUSE I AM LAZY! That is why.
2461 * Abuse luser if we didn't spy a register name.
2465 /* JF allow parenthasized expressions. I hope this works */
2469 /* err = "unknown register in ()"; */
2472 q
--; /* point just before '(' of "(...)" */
2474 * If err == "..." then we lost. Run away.
2475 * Otherwise if reg >= 0 then we saw (Rn).
2479 * If err == "..." then we lost.
2480 * Otherwise paren==1 and reg = register in "()".
2486 * If err == "..." then we lost.
2487 * Otherwise, q points just before "(Rn)", if any.
2488 * If there was a "(...)" then paren==1, and reg is the register.
2492 * We should only seek '-' of "-(...)" if:
2493 * we saw "(...)" paren == 1
2494 * we have no errors so far ! *err
2495 * we did not see '+' of "(...)+" sign < 1
2496 * We don't check len. We want a specific error message later if
2497 * user tries "x^...-(Rn)". This is a feature not a bug.
2501 if (paren
&& sign
< 1)/* !sign is adequate test */
2510 * We have back-tracked over most
2511 * of the crud at the end of an operand.
2512 * Unless err, we know: sign, paren. If paren, we know reg.
2513 * The last case is of an expression "Rn".
2514 * This is worth hunting for if !err, !paren.
2515 * We wouldn't be here if err.
2516 * We remember to save q, in case we didn't want "Rn" anyway.
2520 if (*q
== ' ' && q
>= p
) /* Expect all whitespace reduced to ' '. */
2522 /* reverse over whitespace, but don't */
2523 /* run back over *p */
2524 if (q
> p
&& q
< p
+ 3) /* room for Rn or Rnn exactly? */
2525 reg
= vax_reg_parse (p
[0], p
[1], q
< p
+ 2 ? 0 : p
[2]);
2527 reg
= -1; /* always comes here if no register at all */
2529 * Here with a definitive reg value.
2540 * have reg. -1:absent; else 0:15
2544 * We have: err, at, len, hash, ndx, sign, paren, reg.
2545 * Also, any remaining expression is from *p through *q inclusive.
2546 * Should there be no expression, q==p-1. So expression length = q-p+1.
2547 * This completes the first part: parsing the operand text.
2551 * We now want to boil the data down, checking consistency on the way.
2552 * We want: len, mode, reg, ndx, err, p, q, wrn, bug.
2553 * We will deliver a 4-bit reg, and a 4-bit mode.
2557 * Case of branch operand. Different. No L^B^W^I^S^ allowed for instance.
2571 * p:q whatever was input
2573 * err " " or error message, and other outputs trashed
2575 /* branch operands have restricted forms */
2576 if ((!err
|| !*err
) && access
== 'b')
2578 if (at
|| hash
|| sign
|| paren
|| ndx
>= 0 || reg
>= 0 || len
!= ' ')
2579 err
= "invalid branch operand";
2584 /* Since nobody seems to use it: comment this 'feature'(?) out for now. */
2587 * Case of stand-alone operand. e.g. ".long foo"
2601 * p:q whatever was input
2603 * err " " or error message, and other outputs trashed
2605 if ((!err
|| !*err
) && access
== ' ')
2608 err
= "address prohibits @";
2610 err
= "address prohibits #";
2614 err
= "address prohibits -()";
2616 err
= "address prohibits ()+";
2619 err
= "address prohibits ()";
2621 err
= "address prohibits []";
2623 err
= "address prohibits register";
2624 else if (len
!= ' ')
2625 err
= "address prohibits displacement length specifier";
2628 err
= " "; /* succeed */
2632 #endif /*#Ifdef NEVER*/
2638 * len 's' definition
2640 * p:q demand not empty
2641 * sign 0 by paren==0
2642 * paren 0 by "()" scan logic because "S^" seen
2643 * reg -1 or nn by mistake
2652 if ((!err
|| !*err
) && len
== 's')
2654 if (!hash
|| paren
|| at
|| ndx
>= 0)
2655 err
= "invalid operand of S^#";
2661 * SHIT! we saw S^#Rnn ! put the Rnn back in
2662 * expression. KLUDGE! Use oldq so we don't
2663 * need to know exact length of reg name.
2669 * We have all the expression we will ever get.
2672 err
= "S^# needs expression";
2673 else if (access
== 'r')
2675 err
= " "; /* WIN! */
2679 err
= "S^# may only read-access";
2684 * Case of -(Rn), which is weird case.
2690 * sign -1 by definition
2691 * paren 1 by definition
2692 * reg present by definition
2698 * exp "" enforce empty expression
2699 * ndx optional warn if same as reg
2701 if ((!err
|| !*err
) && sign
< 0)
2703 if (len
!= ' ' || hash
|| at
|| p
<= q
)
2704 err
= "invalid operand of -()";
2707 err
= " "; /* win */
2710 wrn
= "-(PC) unpredictable";
2711 else if (reg
== ndx
)
2712 wrn
= "[]index same as -()register: unpredictable";
2717 * We convert "(Rn)" to "@Rn" for our convenience.
2718 * (I hope this is convenient: has someone got a better way to parse this?)
2719 * A side-effect of this is that "@Rn" is a valid operand.
2721 if (paren
&& !sign
&& !hash
&& !at
&& len
== ' ' && p
> q
)
2728 * Case of (Rn)+, which is slightly different.
2734 * sign +1 by definition
2735 * paren 1 by definition
2736 * reg present by definition
2742 * exp "" enforce empty expression
2743 * ndx optional warn if same as reg
2745 if ((!err
|| !*err
) && sign
> 0)
2747 if (len
!= ' ' || hash
|| p
<= q
)
2748 err
= "invalid operand of ()+";
2751 err
= " "; /* win */
2752 mode
= 8 + (at
? 1 : 0);
2754 wrn
= "(PC)+ unpredictable";
2755 else if (reg
== ndx
)
2756 wrn
= "[]index same as ()+register: unpredictable";
2761 * Case of #, without S^.
2765 * hash 1 by definition
2778 if ((!err
|| !*err
) && hash
)
2780 if (len
!= 'i' && len
!= ' ')
2781 err
= "# conflicts length";
2783 err
= "# bars register";
2789 * SHIT! we saw #Rnn! Put the Rnn back into the expression.
2790 * By using oldq, we don't need to know how long Rnn was.
2794 reg
= -1; /* no register any more */
2796 err
= " "; /* win */
2798 /* JF a bugfix, I think! */
2799 if (at
&& access
== 'a')
2800 vopP
->vop_nbytes
= 4;
2802 mode
= (at
? 9 : 8);
2804 if ((access
== 'm' || access
== 'w') && !at
)
2805 wrn
= "writing or modifying # is unpredictable";
2809 * If !*err, then sign == 0
2814 * Case of Rn. We seperate this one because it has a few special
2815 * errors the remaining modes lack.
2819 * hash 0 by program logic
2821 * sign 0 by program logic
2822 * paren 0 by definition
2823 * reg present by definition
2828 * len ' ' enforce no length
2829 * exp "" enforce empty expression
2830 * ndx optional warn if same as reg
2832 if ((!err
|| !*err
) && !paren
&& reg
>= 0)
2835 err
= "length not needed";
2838 err
= " "; /* win */
2842 err
= "can't []index a register, because it has no address";
2843 else if (access
== 'a')
2844 err
= "a register has no address";
2848 * Idea here is to detect from length of datum
2849 * and from register number if we will touch PC.
2851 * vop_nbytes is number of bytes in operand.
2852 * Compute highest byte affected, compare to PC0.
2854 if ((vopP
->vop_nbytes
+ reg
* 4) > 60)
2855 wrn
= "PC part of operand unpredictable";
2856 err
= " "; /* win */
2861 * If !*err, sign == 0
2863 * paren == 1 OR reg==-1
2867 * Rest of cases fit into one bunch.
2870 * len ' ' or 'b' or 'w' or 'l'
2871 * hash 0 by program logic
2872 * p:q expected (empty is not an error)
2873 * sign 0 by program logic
2878 * out: mode 10 + @ + len
2880 * len ' ' or 'b' or 'w' or 'l'
2882 * ndx optional warn if same as reg
2886 err
= " "; /* win (always) */
2887 mode
= 10 + (at
? 1 : 0);
2894 case ' ': /* assumed B^ until our caller changes it */
2901 * here with completely specified mode
2909 err
= 0; /* " " is no longer an error */
2911 vopP
->vop_mode
= mode
;
2912 vopP
->vop_reg
= reg
;
2913 vopP
->vop_short
= len
;
2914 vopP
->vop_expr_begin
= p
;
2915 vopP
->vop_expr_end
= q
;
2916 vopP
->vop_ndx
= ndx
;
2917 vopP
->vop_error
= err
;
2918 vopP
->vop_warn
= wrn
;
2923 Summary of vip_op outputs.
2927 {@}Rn 5+@ n ' ' optional
2928 branch operand 0 -1 ' ' -1
2930 -(Rn) 7 n ' ' optional
2931 {@}(Rn)+ 8+@ n ' ' optional
2932 {@}#foo, no S^ 8+@ PC " i" optional
2933 {@}{q^}{(Rn)} 10+@+q option " bwl" optional
2937 #ifdef TEST /* #Define to use this testbed. */
2940 * Follows a test program for this function.
2941 * We declare arrays non-local in case some of our tiny-minded machines
2942 * default to small stacks. Also, helps with some debuggers.
2947 char answer
[100]; /* human types into here */
2960 int my_operand_length
;
2961 char my_immediate
[200];
2962 char my_indirect
[200];
2963 char my_displen
[200];
2967 printf ("enter immediate symbols eg enter # ");
2968 gets (my_immediate
);
2969 printf ("enter indirect symbols eg enter @ ");
2971 printf ("enter displen symbols eg enter ^ ");
2973 vip_op_defaults (my_immediate
, my_indirect
, my_displen
);
2976 printf ("access,width (eg 'ab' or 'wh') [empty line to quit] : ");
2981 myaccess
= answer
[0];
2982 mywidth
= answer
[1];
2986 my_operand_length
= 1;
2989 my_operand_length
= 8;
2992 my_operand_length
= 4;
2995 my_operand_length
= 16;
2998 my_operand_length
= 32;
3001 my_operand_length
= 4;
3004 my_operand_length
= 16;
3007 my_operand_length
= 8;
3010 my_operand_length
= 2;
3015 my_operand_length
= 0;
3019 my_operand_length
= 2;
3020 printf ("I dn't understand access width %c\n", mywidth
);
3023 printf ("VAX assembler instruction operand: ");
3026 mybug
= vip_op (answer
, myaccess
, mywidth
, my_operand_length
,
3027 &mymode
, &myreg
, &mylen
, &myleft
, &myright
, &myndx
,
3031 printf ("error: \"%s\"\n", myerr
);
3033 printf (" bug: \"%s\"\n", mybug
);
3038 printf ("warning: \"%s\"\n", mywrn
);
3039 mumble ("mode", mymode
);
3040 mumble ("register", myreg
);
3041 mumble ("index", myndx
);
3042 printf ("width:'%c' ", mylen
);
3043 printf ("expression: \"");
3044 while (myleft
<= myright
)
3045 putchar (*myleft
++);
3051 mumble (text
, value
)
3055 printf ("%s:", text
);
3057 printf ("%xx", value
);
3063 #endif /* ifdef TEST */
3067 const int md_short_jump_size
= 3;
3068 const int md_long_jump_size
= 6;
3069 const int md_reloc_size
= 8; /* Size of relocation record */
3072 md_create_short_jump (ptr
, from_addr
, to_addr
, frag
, to_symbol
)
3074 addressT from_addr
, to_addr
;
3080 offset
= to_addr
- (from_addr
+ 1);
3082 md_number_to_chars (ptr
, offset
, 2);
3086 md_create_long_jump (ptr
, from_addr
, to_addr
, frag
, to_symbol
)
3088 addressT from_addr
, to_addr
;
3094 offset
= to_addr
- S_GET_VALUE (to_symbol
);
3097 md_number_to_chars (ptr
, offset
, 4);
3098 fix_new (frag
, ptr
- frag
->fr_literal
, 4, to_symbol
, (long) 0, 0, NO_RELOC
);
3102 CONST
char *md_shortopts
= "d:STt:V+h:H";
3104 CONST
char *md_shortopts
= "d:STt:V";
3106 struct option md_longopts
[] = {
3107 {NULL
, no_argument
, NULL
, 0}
3109 size_t md_longopts_size
= sizeof(md_longopts
);
3112 md_parse_option (c
, arg
)
3119 as_warn ("SYMBOL TABLE not implemented");
3123 as_warn ("TOKEN TRACE not implemented");
3127 as_warn ("Displacement length %s ignored!", arg
);
3131 as_warn ("I don't need or use temp. file \"%s\".", arg
);
3135 as_warn ("I don't use an interpass file! -V ignored");
3139 case '+': /* For g++ */
3142 case 'h': /* No hashing of mixed-case names */
3144 extern char vms_name_mapping
;
3145 vms_name_mapping
= atoi (arg
);
3149 case 'H': /* Show new symbol after hash truncation */
3161 md_show_usage (stream
)
3166 -d LENGTH ignored\n\
3174 /* We have no need to default values of symbols. */
3178 md_undefined_symbol (name
)
3184 /* Parse an operand that is machine-specific.
3185 We just return without modifying the expression if we have nothing
3190 md_operand (expressionP
)
3191 expressionS
*expressionP
;
3195 /* Round up a section size to the appropriate boundary. */
3197 md_section_align (segment
, size
)
3201 return size
; /* Byte alignment is fine */
3204 /* Exactly what point is a PC-relative offset relative TO?
3205 On the vax, they're relative to the address of the offset, plus
3206 its size. (??? Is this right? FIXME-SOON) */
3208 md_pcrel_from (fixP
)
3211 return fixP
->fx_size
+ fixP
->fx_where
+ fixP
->fx_frag
->fr_address
;
3214 /* end of tc-vax.c */