1 /* Print Motorola 68k instructions for GDB, the GNU debugger.
2 Copyright 1986, 1987, 1989, 1991 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program 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 of the License, or
9 (at your option) any later version.
11 This program 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 this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
22 #include "opcode/m68k.h"
25 /* Local function prototypes */
28 fetch_arg
PARAMS ((unsigned char *, int, int));
31 print_base
PARAMS ((int, int, FILE *));
33 static unsigned char *
34 print_indexed
PARAMS ((int, unsigned char *, CORE_ADDR
, FILE *));
36 static unsigned char *
37 print_insn_arg
PARAMS ((char *, unsigned char *, unsigned char *, CORE_ADDR
,
40 /* 68k instructions are never longer than this many bytes. */
43 /* Number of elements in the opcode table. */
44 #define NOPCODES (sizeof m68k_opcodes / sizeof m68k_opcodes[0])
46 extern char *reg_names
[];
47 char *fpcr_names
[] = { "", "fpiar", "fpsr", "fpiar/fpsr", "fpcr",
48 "fpiar/fpcr", "fpsr/fpcr", "fpiar-fpcr"};
51 #define NEXTBYTE(p) (p += 2, ((char *)p)[-1])
54 (p += 2, ((((char *)p)[-2]) << 8) + p[-1])
57 (p += 4, (((((p[-4] << 8) + p[-3]) << 8) + p[-2]) << 8) + p[-1])
59 #define NEXTSINGLE(p) \
60 (p += 4, *((float *)(p - 4)))
62 #define NEXTDOUBLE(p) \
63 (p += 8, *((double *)(p - 8)))
65 #define NEXTEXTEND(p) \
66 (p += 12, 0.0) /* Need a function to convert from extended to double
69 #define NEXTPACKED(p) \
70 (p += 12, 0.0) /* Need a function to convert from packed to double
71 precision. Actually, it's easier to print a
72 packed number than a double anyway, so maybe
73 there should be a special case to handle this... */
75 /* Print the m68k instruction at address MEMADDR in debugged memory,
76 on STREAM. Returns length of the instruction, in bytes. */
79 print_insn (memaddr
, stream
)
83 unsigned char buffer
[MAXLEN
];
85 register unsigned char *p
;
87 register int bestmask
;
90 read_memory (memaddr
, (char *) buffer
, MAXLEN
);
94 for (i
= 0; i
< NOPCODES
; i
++)
96 register unsigned int opcode
= m68k_opcodes
[i
].opcode
;
97 register unsigned int match
= m68k_opcodes
[i
].match
;
98 if (((0xff & buffer
[0] & (match
>> 24)) == (0xff & (opcode
>> 24)))
99 && ((0xff & buffer
[1] & (match
>> 16)) == (0xff & (opcode
>> 16)))
100 && ((0xff & buffer
[2] & (match
>> 8)) == (0xff & (opcode
>> 8)))
101 && ((0xff & buffer
[3] & match
) == (0xff & opcode
)))
103 /* Don't use for printout the variants of divul and divsl
104 that have the same register number in two places.
105 The more general variants will match instead. */
106 for (d
= m68k_opcodes
[i
].args
; *d
; d
+= 2)
110 /* Don't use for printout the variants of most floating
111 point coprocessor instructions which use the same
112 register number in two places, as above. */
114 for (d
= m68k_opcodes
[i
].args
; *d
; d
+= 2)
118 if (*d
== 0 && match
> bestmask
)
126 /* Handle undefined instructions. */
129 fprintf_filtered (stream
, "0%o", (buffer
[0] << 8) + buffer
[1]);
133 fprintf_filtered (stream
, "%s", m68k_opcodes
[best
].name
);
135 /* Point at first word of argument data,
136 and at descriptor for first argument. */
139 /* Why do this this way? -MelloN */
140 for (d
= m68k_opcodes
[best
].args
; *d
; d
+= 2)
144 if (d
[1] == 'l' && p
- buffer
< 6)
146 else if (p
- buffer
< 4 && d
[1] != 'C' && d
[1] != '8' )
149 if (d
[1] >= '1' && d
[1] <= '3' && p
- buffer
< 4)
151 if (d
[1] >= '4' && d
[1] <= '6' && p
- buffer
< 6)
153 if ((d
[0] == 'L' || d
[0] == 'l') && d
[1] == 'w' && p
- buffer
< 4)
157 d
= m68k_opcodes
[best
].args
;
160 fputs_filtered (" ", stream
);
164 p
= print_insn_arg (d
, buffer
, p
, memaddr
+ p
- buffer
, stream
);
166 if (*d
&& *(d
- 2) != 'I' && *d
!= 'k')
167 fputs_filtered (",", stream
);
172 static unsigned char *
173 print_insn_arg (d
, buffer
, p
, addr
, stream
)
175 unsigned char *buffer
;
176 register unsigned char *p
;
177 CORE_ADDR addr
; /* PC for this arg to be relative to */
181 register int place
= d
[1];
183 register char *regname
;
184 register unsigned char *p1
;
185 register double flval
;
191 fprintf_filtered (stream
, "ccr");
195 fprintf_filtered (stream
, "sr");
199 fprintf_filtered (stream
, "usp");
204 static struct { char *name
; int value
; } names
[]
205 = {{"sfc", 0x000}, {"dfc", 0x001}, {"cacr", 0x002},
206 {"usp", 0x800}, {"vbr", 0x801}, {"caar", 0x802},
207 {"msp", 0x803}, {"isp", 0x804}};
209 val
= fetch_arg (buffer
, place
, 12);
210 for (regno
= sizeof names
/ sizeof names
[0] - 1; regno
>= 0; regno
--)
211 if (names
[regno
].value
== val
)
213 fprintf_filtered (stream
, names
[regno
].name
);
217 fprintf_filtered (stream
, "%d", val
);
222 val
= fetch_arg (buffer
, place
, 3);
223 /* 0 means 8, except for the bkpt instruction... */
224 if (val
== 0 && d
[1] != 's')
226 fprintf_filtered (stream
, "#%d", val
);
230 val
= fetch_arg (buffer
, place
, 8);
233 fprintf_filtered (stream
, "#%d", val
);
237 val
= fetch_arg (buffer
, place
, 4);
238 fprintf_filtered (stream
, "#%d", val
);
242 fprintf_filtered (stream
, "%s", reg_names
[fetch_arg (buffer
, place
, 3)]);
246 fprintf_filtered (stream
, "%s",
247 reg_names
[fetch_arg (buffer
, place
, 3) + 010]);
251 fprintf_filtered (stream
, "%s", reg_names
[fetch_arg (buffer
, place
, 4)]);
255 fprintf_filtered (stream
, "fp%d", fetch_arg (buffer
, place
, 3));
259 val
= fetch_arg (buffer
, place
, 6);
261 fprintf_filtered (stream
, "%s", reg_names
[val
& 7]);
263 fprintf_filtered (stream
, "%d", val
);
267 fprintf_filtered (stream
, "%s@+",
268 reg_names
[fetch_arg (buffer
, place
, 3) + 8]);
272 fprintf_filtered (stream
, "%s@-",
273 reg_names
[fetch_arg (buffer
, place
, 3) + 8]);
278 fprintf_filtered (stream
, "{%s}", reg_names
[fetch_arg (buffer
, place
, 3)]);
279 else if (place
== 'C')
281 val
= fetch_arg (buffer
, place
, 7);
282 if ( val
> 63 ) /* This is a signed constant. */
284 fprintf_filtered (stream
, "{#%d}", val
);
287 error ("Invalid arg format in opcode table: \"%c%c\".",
293 p1
= buffer
+ (*d
== '#' ? 2 : 4);
295 val
= fetch_arg (buffer
, place
, 4);
296 else if (place
== 'C')
297 val
= fetch_arg (buffer
, place
, 7);
298 else if (place
== '8')
299 val
= fetch_arg (buffer
, place
, 3);
300 else if (place
== '3')
301 val
= fetch_arg (buffer
, place
, 8);
302 else if (place
== 'b')
304 else if (place
== 'w')
306 else if (place
== 'l')
309 error ("Invalid arg format in opcode table: \"%c%c\".",
311 fprintf_filtered (stream
, "#%d", val
);
317 else if (place
== 'B')
318 val
= ((char *)buffer
)[1];
319 else if (place
== 'w' || place
== 'W')
321 else if (place
== 'l' || place
== 'L')
323 else if (place
== 'g')
325 val
= ((char *)buffer
)[1];
331 else if (place
== 'c')
333 if (buffer
[1] & 0x40) /* If bit six is one, long offset */
339 error ("Invalid arg format in opcode table: \"%c%c\".",
342 print_address (addr
+ val
, stream
);
347 fprintf_filtered (stream
, "%s@(%d)",
348 reg_names
[fetch_arg (buffer
, place
, 3)], val
);
352 fprintf_filtered (stream
, "%s",
353 fpcr_names
[fetch_arg (buffer
, place
, 3)]);
357 val
= fetch_arg (buffer
, 'd', 3); /* Get coprocessor ID... */
358 if (val
!= 1) /* Unusual coprocessor ID? */
359 fprintf_filtered (stream
, "(cpid=%d) ", val
);
361 p
+= 2; /* Skip coprocessor extended operands */
377 val
= fetch_arg (buffer
, 'x', 6);
378 val
= ((val
& 7) << 3) + ((val
>> 3) & 7);
381 val
= fetch_arg (buffer
, 's', 6);
383 /* Get register number assuming address register. */
384 regno
= (val
& 7) + 8;
385 regname
= reg_names
[regno
];
389 fprintf_filtered (stream
, "%s", reg_names
[val
]);
393 fprintf_filtered (stream
, "%s", regname
);
397 fprintf_filtered (stream
, "%s@", regname
);
401 fprintf_filtered (stream
, "%s@+", regname
);
405 fprintf_filtered (stream
, "%s@-", regname
);
410 fprintf_filtered (stream
, "%s@(%d)", regname
, val
);
414 p
= print_indexed (regno
, p
, addr
, stream
);
422 fprintf_filtered (stream
, "@#");
423 print_address (val
, stream
);
428 fprintf_filtered (stream
, "@#");
429 print_address (val
, stream
);
434 print_address (addr
+ val
, stream
);
438 p
= print_indexed (-1, p
, addr
, stream
);
442 flt_p
= 1; /* Assume it's a float... */
461 flval
= NEXTSINGLE(p
);
465 flval
= NEXTDOUBLE(p
);
469 flval
= NEXTEXTEND(p
);
473 flval
= NEXTPACKED(p
);
477 error ("Invalid arg format in opcode table: \"%c%c\".",
480 if ( flt_p
) /* Print a float? */
481 fprintf_filtered (stream
, "#%g", flval
);
483 fprintf_filtered (stream
, "#%d", val
);
487 fprintf_filtered (stream
, "<invalid address mode 0%o>", val
);
499 /* Move the pointer ahead if this point is farther ahead
504 fputs_filtered ("#0", stream
);
509 register int newval
= 0;
510 for (regno
= 0; regno
< 16; ++regno
)
511 if (val
& (0x8000 >> regno
))
512 newval
|= 1 << regno
;
517 for (regno
= 0; regno
< 16; ++regno
)
518 if (val
& (1 << regno
))
522 fputs_filtered ("/", stream
);
524 fprintf_filtered (stream
, "%s", reg_names
[regno
]);
526 while (val
& (1 << (regno
+ 1)))
528 if (regno
> first_regno
)
529 fprintf_filtered (stream
, "-%s", reg_names
[regno
]);
532 else if (place
== '3')
536 val
= fetch_arg (buffer
, place
, 8);
539 fputs_filtered ("#0", stream
);
544 register int newval
= 0;
545 for (regno
= 0; regno
< 8; ++regno
)
546 if (val
& (0x80 >> regno
))
547 newval
|= 1 << regno
;
552 for (regno
= 0; regno
< 8; ++regno
)
553 if (val
& (1 << regno
))
557 fputs_filtered ("/", stream
);
559 fprintf_filtered (stream
, "fp%d", regno
);
561 while (val
& (1 << (regno
+ 1)))
563 if (regno
> first_regno
)
564 fprintf_filtered (stream
, "-fp%d", regno
);
572 error ("Invalid arg format in opcode table: \"%c\".", *d
);
575 return (unsigned char *) p
;
578 /* Fetch BITS bits from a position in the instruction specified by CODE.
579 CODE is a "place to put an argument", or 'x' for a destination
580 that is a general address (mode and register).
581 BUFFER contains the instruction. */
584 fetch_arg (buffer
, code
, bits
)
585 unsigned char *buffer
;
596 case 'd': /* Destination, for register or quick. */
597 val
= (buffer
[0] << 8) + buffer
[1];
601 case 'x': /* Destination, for general arg */
602 val
= (buffer
[0] << 8) + buffer
[1];
607 val
= (buffer
[3] >> 4);
615 val
= (buffer
[2] << 8) + buffer
[3];
620 val
= (buffer
[2] << 8) + buffer
[3];
626 val
= (buffer
[2] << 8) + buffer
[3];
630 val
= (buffer
[4] << 8) + buffer
[5];
635 val
= (buffer
[4] << 8) + buffer
[5];
640 val
= (buffer
[4] << 8) + buffer
[5];
644 val
= (buffer
[2] << 8) + buffer
[3];
649 val
= (buffer
[2] << 8) + buffer
[3];
678 /* Print an indexed argument. The base register is BASEREG (-1 for pc).
679 P points to extension word, in buffer.
680 ADDR is the nominal core address of that extension word. */
682 static unsigned char *
683 print_indexed (basereg
, p
, addr
, stream
)
690 static char *scales
[] = {"", "*2", "*4", "*8"};
691 register int base_disp
;
692 register int outer_disp
;
697 /* Generate the text for the index register.
698 Where this will be output is not yet determined. */
699 sprintf (buf
, "[%s.%c%s]",
700 reg_names
[(word
>> 12) & 0xf],
701 (word
& 0x800) ? 'l' : 'w',
702 scales
[(word
>> 9) & 3]);
704 /* Handle the 68000 style of indexing. */
706 if ((word
& 0x100) == 0)
709 ((word
& 0x80) ? word
| 0xff00 : word
& 0xff)
710 + ((basereg
== -1) ? addr
: 0),
712 fputs_filtered (buf
, stream
);
716 /* Handle the generalized kind. */
717 /* First, compute the displacement to add to the base register. */
724 switch ((word
>> 4) & 3)
727 base_disp
= NEXTWORD (p
);
730 base_disp
= NEXTLONG (p
);
735 /* Handle single-level case (not indirect) */
739 print_base (basereg
, base_disp
, stream
);
740 fputs_filtered (buf
, stream
);
744 /* Two level. Compute displacement to add after indirection. */
750 outer_disp
= NEXTWORD (p
);
753 outer_disp
= NEXTLONG (p
);
756 fprintf_filtered (stream
, "%d(", outer_disp
);
757 print_base (basereg
, base_disp
, stream
);
759 /* If postindexed, print the closeparen before the index. */
761 fprintf_filtered (stream
, ")%s", buf
);
762 /* If preindexed, print the closeparen after the index. */
764 fprintf_filtered (stream
, "%s)", buf
);
769 /* Print a base register REGNO and displacement DISP, on STREAM.
770 REGNO = -1 for pc, -2 for none (suppressed). */
773 print_base (regno
, disp
, stream
)
779 fprintf_filtered (stream
, "%d", disp
);
780 else if (regno
== -1)
781 fprintf_filtered (stream
, "0x%x", disp
);
783 fprintf_filtered (stream
, "%d(%s)", disp
, reg_names
[regno
]);
This page took 0.080852 seconds and 4 git commands to generate.