]> git.ipfire.org Git - thirdparty/binutils-gdb.git/blob - gdb/h8300-tdep.c
import gdb-1999-07-07 post reformat
[thirdparty/binutils-gdb.git] / gdb / h8300-tdep.c
1 /* Target-machine dependent code for Hitachi H8/300, for GDB.
2 Copyright (C) 1988, 1990, 1991 Free Software Foundation, Inc.
3
4 This file is part of GDB.
5
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.
10
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.
15
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., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
20
21 /*
22 Contributed by Steve Chamberlain
23 sac@cygnus.com
24 */
25
26 #include "defs.h"
27 #include "frame.h"
28 #include "obstack.h"
29 #include "symtab.h"
30 #include "dis-asm.h"
31 #include "gdbcmd.h"
32 #include "gdbtypes.h"
33 #include "gdbcore.h"
34 #include "gdb_string.h"
35 #include "value.h"
36
37 extern int h8300hmode, h8300smode;
38
39 #undef NUM_REGS
40 #define NUM_REGS 11
41
42 #define UNSIGNED_SHORT(X) ((X) & 0xffff)
43
44 #define IS_PUSH(x) ((x & 0xfff0)==0x6df0)
45 #define IS_PUSH_FP(x) (x == 0x6df6)
46 #define IS_MOVE_FP(x) (x == 0x0d76 || x == 0x0ff6)
47 #define IS_MOV_SP_FP(x) (x == 0x0d76 || x == 0x0ff6)
48 #define IS_SUB2_SP(x) (x==0x1b87)
49 #define IS_SUB4_SP(x) (x==0x1b97)
50 #define IS_SUBL_SP(x) (x==0x7a37)
51 #define IS_MOVK_R5(x) (x==0x7905)
52 #define IS_SUB_R5SP(x) (x==0x1957)
53
54
55 /* The register names change depending on whether the h8300h processor
56 type is selected. */
57
58 static char *original_register_names[] = REGISTER_NAMES;
59
60 static char *h8300h_register_names[] =
61 {"er0", "er1", "er2", "er3", "er4", "er5", "er6",
62 "sp", "ccr", "pc", "cycles", "tick", "inst"};
63
64 char **h8300_register_names = original_register_names;
65
66
67 /* Local function declarations. */
68
69 static CORE_ADDR examine_prologue ();
70 static void set_machine_hook PARAMS ((char *filename));
71
72 void h8300_frame_find_saved_regs ();
73
74 CORE_ADDR
75 h8300_skip_prologue (start_pc)
76 CORE_ADDR start_pc;
77 {
78 short int w;
79 int adjust = 0;
80
81 /* Skip past all push and stm insns. */
82 while (1)
83 {
84 w = read_memory_unsigned_integer (start_pc, 2);
85 /* First look for push insns. */
86 if (w == 0x0100 || w == 0x0110 || w == 0x0120 || w == 0x0130)
87 {
88 w = read_memory_unsigned_integer (start_pc + 2, 2);
89 adjust = 2;
90 }
91
92 if (IS_PUSH (w))
93 {
94 start_pc += 2 + adjust;
95 w = read_memory_unsigned_integer (start_pc, 2);
96 continue;
97 }
98 adjust = 0;
99 break;
100 }
101
102 /* Skip past a move to FP, either word or long sized */
103 w = read_memory_unsigned_integer (start_pc, 2);
104 if (w == 0x0100)
105 {
106 w = read_memory_unsigned_integer (start_pc + 2, 2);
107 adjust += 2;
108 }
109
110 if (IS_MOVE_FP (w))
111 {
112 start_pc += 2 + adjust;
113 w = read_memory_unsigned_integer (start_pc, 2);
114 }
115
116 /* Check for loading either a word constant into r5;
117 long versions are handled by the SUBL_SP below. */
118 if (IS_MOVK_R5 (w))
119 {
120 start_pc += 2;
121 w = read_memory_unsigned_integer (start_pc, 2);
122 }
123
124 /* Now check for subtracting r5 from sp, word sized only. */
125 if (IS_SUB_R5SP (w))
126 {
127 start_pc += 2 + adjust;
128 w = read_memory_unsigned_integer (start_pc, 2);
129 }
130
131 /* Check for subs #2 and subs #4. */
132 while (IS_SUB2_SP (w) || IS_SUB4_SP (w))
133 {
134 start_pc += 2 + adjust;
135 w = read_memory_unsigned_integer (start_pc, 2);
136 }
137
138 /* Check for a 32bit subtract. */
139 if (IS_SUBL_SP (w))
140 start_pc += 6 + adjust;
141
142 return start_pc;
143 }
144
145 int
146 gdb_print_insn_h8300 (memaddr, info)
147 bfd_vma memaddr;
148 disassemble_info *info;
149 {
150 if (h8300smode)
151 return print_insn_h8300s (memaddr, info);
152 else if (h8300hmode)
153 return print_insn_h8300h (memaddr, info);
154 else
155 return print_insn_h8300 (memaddr, info);
156 }
157
158 /* Given a GDB frame, determine the address of the calling function's frame.
159 This will be used to create a new GDB frame struct, and then
160 INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame.
161
162 For us, the frame address is its stack pointer value, so we look up
163 the function prologue to determine the caller's sp value, and return it. */
164
165 CORE_ADDR
166 h8300_frame_chain (thisframe)
167 struct frame_info *thisframe;
168 {
169 if (PC_IN_CALL_DUMMY (thisframe->pc, thisframe->frame, thisframe->frame))
170 { /* initialize the from_pc now */
171 thisframe->from_pc = generic_read_register_dummy (thisframe->pc,
172 thisframe->frame,
173 PC_REGNUM);
174 return thisframe->frame;
175 }
176 h8300_frame_find_saved_regs (thisframe, (struct frame_saved_regs *) 0);
177 return thisframe->fsr->regs[SP_REGNUM];
178 }
179
180 /* Put here the code to store, into a struct frame_saved_regs,
181 the addresses of the saved registers of frame described by FRAME_INFO.
182 This includes special registers such as pc and fp saved in special
183 ways in the stack frame. sp is even more special:
184 the address we return for it IS the sp for the next frame.
185
186 We cache the result of doing this in the frame_obstack, since it is
187 fairly expensive. */
188
189 void
190 h8300_frame_find_saved_regs (fi, fsr)
191 struct frame_info *fi;
192 struct frame_saved_regs *fsr;
193 {
194 register struct frame_saved_regs *cache_fsr;
195 CORE_ADDR ip;
196 struct symtab_and_line sal;
197 CORE_ADDR limit;
198
199 if (!fi->fsr)
200 {
201 cache_fsr = (struct frame_saved_regs *)
202 frame_obstack_alloc (sizeof (struct frame_saved_regs));
203 memset (cache_fsr, '\0', sizeof (struct frame_saved_regs));
204
205 fi->fsr = cache_fsr;
206
207 if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
208 { /* no more to do. */
209 if (fsr)
210 *fsr = *fi->fsr;
211 return;
212 }
213 /* Find the start and end of the function prologue. If the PC
214 is in the function prologue, we only consider the part that
215 has executed already. */
216
217 ip = get_pc_function_start (fi->pc);
218 sal = find_pc_line (ip, 0);
219 limit = (sal.end && sal.end < fi->pc) ? sal.end : fi->pc;
220
221 /* This will fill in fields in *fi as well as in cache_fsr. */
222 examine_prologue (ip, limit, fi->frame, cache_fsr, fi);
223 }
224
225 if (fsr)
226 *fsr = *fi->fsr;
227 }
228
229 /* Fetch the instruction at ADDR, returning 0 if ADDR is beyond LIM or
230 is not the address of a valid instruction, the address of the next
231 instruction beyond ADDR otherwise. *PWORD1 receives the first word
232 of the instruction. */
233
234 CORE_ADDR
235 NEXT_PROLOGUE_INSN (addr, lim, pword1)
236 CORE_ADDR addr;
237 CORE_ADDR lim;
238 INSN_WORD *pword1;
239 {
240 char buf[2];
241 if (addr < lim + 8)
242 {
243 read_memory (addr, buf, 2);
244 *pword1 = extract_signed_integer (buf, 2);
245
246 return addr + 2;
247 }
248 return 0;
249 }
250
251 /* Examine the prologue of a function. `ip' points to the first instruction.
252 `limit' is the limit of the prologue (e.g. the addr of the first
253 linenumber, or perhaps the program counter if we're stepping through).
254 `frame_sp' is the stack pointer value in use in this frame.
255 `fsr' is a pointer to a frame_saved_regs structure into which we put
256 info about the registers saved by this frame.
257 `fi' is a struct frame_info pointer; we fill in various fields in it
258 to reflect the offsets of the arg pointer and the locals pointer. */
259
260 static CORE_ADDR
261 examine_prologue (ip, limit, after_prolog_fp, fsr, fi)
262 register CORE_ADDR ip;
263 register CORE_ADDR limit;
264 CORE_ADDR after_prolog_fp;
265 struct frame_saved_regs *fsr;
266 struct frame_info *fi;
267 {
268 register CORE_ADDR next_ip;
269 int r;
270 int have_fp = 0;
271 INSN_WORD insn_word;
272 /* Number of things pushed onto stack, starts at 2/4, 'cause the
273 PC is already there */
274 unsigned int reg_save_depth = h8300hmode ? 4 : 2;
275
276 unsigned int auto_depth = 0; /* Number of bytes of autos */
277
278 char in_frame[11]; /* One for each reg */
279
280 int adjust = 0;
281
282 memset (in_frame, 1, 11);
283 for (r = 0; r < 8; r++)
284 {
285 fsr->regs[r] = 0;
286 }
287 if (after_prolog_fp == 0)
288 {
289 after_prolog_fp = read_register (SP_REGNUM);
290 }
291
292 /* If the PC isn't valid, quit now. */
293 if (ip == 0 || ip & (h8300hmode ? ~0xffffff : ~0xffff))
294 return 0;
295
296 next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
297
298 if (insn_word == 0x0100)
299 {
300 insn_word = read_memory_unsigned_integer (ip + 2, 2);
301 adjust = 2;
302 }
303
304 /* Skip over any fp push instructions */
305 fsr->regs[6] = after_prolog_fp;
306 while (next_ip && IS_PUSH_FP (insn_word))
307 {
308 ip = next_ip + adjust;
309
310 in_frame[insn_word & 0x7] = reg_save_depth;
311 next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
312 reg_save_depth += 2 + adjust;
313 }
314
315 /* Is this a move into the fp */
316 if (next_ip && IS_MOV_SP_FP (insn_word))
317 {
318 ip = next_ip;
319 next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
320 have_fp = 1;
321 }
322
323 /* Skip over any stack adjustment, happens either with a number of
324 sub#2,sp or a mov #x,r5 sub r5,sp */
325
326 if (next_ip && (IS_SUB2_SP (insn_word) || IS_SUB4_SP (insn_word)))
327 {
328 while (next_ip && (IS_SUB2_SP (insn_word) || IS_SUB4_SP (insn_word)))
329 {
330 auto_depth += IS_SUB2_SP (insn_word) ? 2 : 4;
331 ip = next_ip;
332 next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
333 }
334 }
335 else
336 {
337 if (next_ip && IS_MOVK_R5 (insn_word))
338 {
339 ip = next_ip;
340 next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
341 auto_depth += insn_word;
342
343 next_ip = NEXT_PROLOGUE_INSN (next_ip, limit, &insn_word);
344 auto_depth += insn_word;
345 }
346 if (next_ip && IS_SUBL_SP (insn_word))
347 {
348 ip = next_ip;
349 auto_depth += read_memory_unsigned_integer (ip, 4);
350 ip += 4;
351
352 next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
353 }
354 }
355
356 /* Now examine the push insns to determine where everything lives
357 on the stack. */
358 while (1)
359 {
360 adjust = 0;
361 if (!next_ip)
362 break;
363
364 if (insn_word == 0x0100)
365 {
366 ip = next_ip;
367 next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
368 adjust = 2;
369 }
370
371 if (IS_PUSH (insn_word))
372 {
373 ip = next_ip;
374 next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
375 fsr->regs[r] = after_prolog_fp + auto_depth;
376 auto_depth += 2 + adjust;
377 continue;
378 }
379
380 /* Now check for push multiple insns. */
381 if (insn_word == 0x0110 || insn_word == 0x0120 || insn_word == 0x0130)
382 {
383 int count = ((insn_word >> 4) & 0xf) + 1;
384 int start, i;
385
386 ip = next_ip;
387 next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
388 start = insn_word & 0x7;
389
390 for (i = start; i <= start + count; i++)
391 {
392 fsr->regs[i] = after_prolog_fp + auto_depth;
393 auto_depth += 4;
394 }
395 }
396 break;
397 }
398
399 /* The args are always reffed based from the stack pointer */
400 fi->args_pointer = after_prolog_fp;
401 /* Locals are always reffed based from the fp */
402 fi->locals_pointer = after_prolog_fp;
403 /* The PC is at a known place */
404 fi->from_pc = read_memory_unsigned_integer (after_prolog_fp + BINWORD, BINWORD);
405
406 /* Rememeber any others too */
407 in_frame[PC_REGNUM] = 0;
408
409 if (have_fp)
410 /* We keep the old FP in the SP spot */
411 fsr->regs[SP_REGNUM] = read_memory_unsigned_integer (fsr->regs[6], BINWORD);
412 else
413 fsr->regs[SP_REGNUM] = after_prolog_fp + auto_depth;
414
415 return (ip);
416 }
417
418 void
419 h8300_init_extra_frame_info (fromleaf, fi)
420 int fromleaf;
421 struct frame_info *fi;
422 {
423 fi->fsr = 0; /* Not yet allocated */
424 fi->args_pointer = 0; /* Unknown */
425 fi->locals_pointer = 0; /* Unknown */
426 fi->from_pc = 0;
427 if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
428 { /* anything special to do? */
429 return;
430 }
431 }
432
433 /* Return the saved PC from this frame.
434
435 If the frame has a memory copy of SRP_REGNUM, use that. If not,
436 just use the register SRP_REGNUM itself. */
437
438 CORE_ADDR
439 h8300_frame_saved_pc (frame)
440 struct frame_info *frame;
441 {
442 if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame))
443 return generic_read_register_dummy (frame->pc, frame->frame, PC_REGNUM);
444 else
445 return frame->from_pc;
446 }
447
448 CORE_ADDR
449 frame_locals_address (fi)
450 struct frame_info *fi;
451 {
452 if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
453 return (CORE_ADDR) 0; /* Not sure what else to do... */
454 if (!fi->locals_pointer)
455 {
456 struct frame_saved_regs ignore;
457
458 get_frame_saved_regs (fi, &ignore);
459
460 }
461 return fi->locals_pointer;
462 }
463
464 /* Return the address of the argument block for the frame
465 described by FI. Returns 0 if the address is unknown. */
466
467 CORE_ADDR
468 frame_args_address (fi)
469 struct frame_info *fi;
470 {
471 if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
472 return (CORE_ADDR) 0; /* Not sure what else to do... */
473 if (!fi->args_pointer)
474 {
475 struct frame_saved_regs ignore;
476
477 get_frame_saved_regs (fi, &ignore);
478
479 }
480
481 return fi->args_pointer;
482 }
483
484 /* Function: push_arguments
485 Setup the function arguments for calling a function in the inferior.
486
487 On the Hitachi H8/300 architecture, there are three registers (R0 to R2)
488 which are dedicated for passing function arguments. Up to the first
489 three arguments (depending on size) may go into these registers.
490 The rest go on the stack.
491
492 Arguments that are smaller than WORDSIZE bytes will still take up a
493 whole register or a whole WORDSIZE word on the stack, and will be
494 right-justified in the register or the stack word. This includes
495 chars and small aggregate types. Note that WORDSIZE depends on the
496 cpu type.
497
498 Arguments that are larger than WORDSIZE bytes will be split between
499 two or more registers as available, but will NOT be split between a
500 register and the stack.
501
502 An exceptional case exists for struct arguments (and possibly other
503 aggregates such as arrays) -- if the size is larger than WORDSIZE
504 bytes but not a multiple of WORDSIZE bytes. In this case the
505 argument is never split between the registers and the stack, but
506 instead is copied in its entirety onto the stack, AND also copied
507 into as many registers as there is room for. In other words, space
508 in registers permitting, two copies of the same argument are passed
509 in. As far as I can tell, only the one on the stack is used,
510 although that may be a function of the level of compiler
511 optimization. I suspect this is a compiler bug. Arguments of
512 these odd sizes are left-justified within the word (as opposed to
513 arguments smaller than WORDSIZE bytes, which are right-justified).
514
515 If the function is to return an aggregate type such as a struct,
516 the caller must allocate space into which the callee will copy the
517 return value. In this case, a pointer to the return value location
518 is passed into the callee in register R0, which displaces one of
519 the other arguments passed in via registers R0 to R2. */
520
521 CORE_ADDR
522 h8300_push_arguments (nargs, args, sp, struct_return, struct_addr)
523 int nargs;
524 struct value **args;
525 CORE_ADDR sp;
526 unsigned char struct_return;
527 CORE_ADDR struct_addr;
528 {
529 int stack_align, stack_alloc, stack_offset;
530 int wordsize;
531 int argreg;
532 int argnum;
533 struct type *type;
534 CORE_ADDR regval;
535 char *val;
536 char valbuf[4];
537 int len;
538
539 if (h8300hmode || h8300smode)
540 {
541 stack_align = 3;
542 wordsize = 4;
543 }
544 else
545 {
546 stack_align = 1;
547 wordsize = 2;
548 }
549
550 /* first force sp to a n-byte alignment */
551 sp = sp & ~stack_align;
552
553 /* Now make sure there's space on the stack */
554 for (argnum = 0, stack_alloc = 0;
555 argnum < nargs; argnum++)
556 stack_alloc += ((TYPE_LENGTH (VALUE_TYPE (args[argnum])) + stack_align)
557 & ~stack_align);
558 sp -= stack_alloc; /* make room on stack for args */
559 /* we may over-allocate a little here, but that won't hurt anything */
560
561 argreg = ARG0_REGNUM;
562 if (struct_return) /* "struct return" pointer takes up one argreg */
563 {
564 write_register (argreg++, struct_addr);
565 }
566
567 /* Now load as many as possible of the first arguments into
568 registers, and push the rest onto the stack. There are 3N bytes
569 in three registers available. Loop thru args from first to last. */
570
571 for (argnum = 0, stack_offset = 0; argnum < nargs; argnum++)
572 {
573 type = VALUE_TYPE (args[argnum]);
574 len = TYPE_LENGTH (type);
575 memset (valbuf, 0, sizeof (valbuf));
576 if (len < wordsize)
577 {
578 /* the purpose of this is to right-justify the value within the word */
579 memcpy (valbuf + (wordsize - len),
580 (char *) VALUE_CONTENTS (args[argnum]), len);
581 val = valbuf;
582 }
583 else
584 val = (char *) VALUE_CONTENTS (args[argnum]);
585
586 if (len > (ARGLAST_REGNUM + 1 - argreg) * REGISTER_RAW_SIZE (ARG0_REGNUM) ||
587 (len > wordsize && (len & stack_align) != 0))
588 { /* passed on the stack */
589 write_memory (sp + stack_offset, val,
590 len < wordsize ? wordsize : len);
591 stack_offset += (len + stack_align) & ~stack_align;
592 }
593 /* NOTE WELL!!!!! This is not an "else if" clause!!!
594 That's because some *&^%$ things get passed on the stack
595 AND in the registers! */
596 if (len <= (ARGLAST_REGNUM + 1 - argreg) * REGISTER_RAW_SIZE (ARG0_REGNUM))
597 while (len > 0)
598 { /* there's room in registers */
599 regval = extract_address (val, wordsize);
600 write_register (argreg, regval);
601 len -= wordsize;
602 val += wordsize;
603 argreg++;
604 }
605 }
606 return sp;
607 }
608
609 /* Function: push_return_address
610 Setup the return address for a dummy frame, as called by
611 call_function_by_hand. Only necessary when you are using an
612 empty CALL_DUMMY, ie. the target will not actually be executing
613 a JSR/BSR instruction. */
614
615 CORE_ADDR
616 h8300_push_return_address (pc, sp)
617 CORE_ADDR pc;
618 CORE_ADDR sp;
619 {
620 unsigned char buf[4];
621 int wordsize;
622
623 if (h8300hmode || h8300smode)
624 wordsize = 4;
625 else
626 wordsize = 2;
627
628 sp -= wordsize;
629 store_unsigned_integer (buf, wordsize, CALL_DUMMY_ADDRESS ());
630 write_memory (sp, buf, wordsize);
631 return sp;
632 }
633
634 /* Function: pop_frame
635 Restore the machine to the state it had before the current frame
636 was created. Usually used either by the "RETURN" command, or by
637 call_function_by_hand after the dummy_frame is finished. */
638
639 void
640 h8300_pop_frame ()
641 {
642 unsigned regnum;
643 struct frame_saved_regs fsr;
644 struct frame_info *frame = get_current_frame ();
645
646 if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame))
647 {
648 generic_pop_dummy_frame ();
649 }
650 else
651 {
652 get_frame_saved_regs (frame, &fsr);
653
654 for (regnum = 0; regnum < 8; regnum++)
655 {
656 /* Don't forget SP_REGNUM is a frame_saved_regs struct is the
657 actual value we want, not the address of the value we want. */
658 if (fsr.regs[regnum] && regnum != SP_REGNUM)
659 write_register (regnum,
660 read_memory_integer (fsr.regs[regnum], BINWORD));
661 else if (fsr.regs[regnum] && regnum == SP_REGNUM)
662 write_register (regnum, frame->frame + 2 * BINWORD);
663 }
664
665 /* Don't forget the update the PC too! */
666 write_pc (frame->from_pc);
667 }
668 flush_cached_frames ();
669 }
670
671 /* Function: extract_return_value
672 Figure out where in REGBUF the called function has left its return value.
673 Copy that into VALBUF. Be sure to account for CPU type. */
674
675 void
676 h8300_extract_return_value (type, regbuf, valbuf)
677 struct type *type;
678 char *regbuf;
679 char *valbuf;
680 {
681 int wordsize, len;
682
683 if (h8300smode || h8300hmode)
684 wordsize = 4;
685 else
686 wordsize = 2;
687
688 len = TYPE_LENGTH (type);
689
690 switch (len)
691 {
692 case 1: /* (char) */
693 case 2: /* (short), (int) */
694 memcpy (valbuf, regbuf + REGISTER_BYTE (0) + (wordsize - len), len);
695 break;
696 case 4: /* (long), (float) */
697 if (h8300smode || h8300hmode)
698 {
699 memcpy (valbuf, regbuf + REGISTER_BYTE (0), 4);
700 }
701 else
702 {
703 memcpy (valbuf, regbuf + REGISTER_BYTE (0), 2);
704 memcpy (valbuf + 2, regbuf + REGISTER_BYTE (1), 2);
705 }
706 break;
707 case 8: /* (double) (doesn't seem to happen, which is good,
708 because this almost certainly isn't right. */
709 error ("I don't know how a double is returned.");
710 break;
711 }
712 }
713
714 /* Function: store_return_value
715 Place the appropriate value in the appropriate registers.
716 Primarily used by the RETURN command. */
717
718 void
719 h8300_store_return_value (type, valbuf)
720 struct type *type;
721 char *valbuf;
722 {
723 int wordsize, len, regval;
724
725 if (h8300hmode || h8300smode)
726 wordsize = 4;
727 else
728 wordsize = 2;
729
730 len = TYPE_LENGTH (type);
731 switch (len)
732 {
733 case 1: /* char */
734 case 2: /* short, int */
735 regval = extract_address (valbuf, len);
736 write_register (0, regval);
737 break;
738 case 4: /* long, float */
739 regval = extract_address (valbuf, len);
740 if (h8300smode || h8300hmode)
741 {
742 write_register (0, regval);
743 }
744 else
745 {
746 write_register (0, regval >> 16);
747 write_register (1, regval & 0xffff);
748 }
749 break;
750 case 8: /* presumeably double, but doesn't seem to happen */
751 error ("I don't know how to return a double.");
752 break;
753 }
754 }
755
756 struct cmd_list_element *setmemorylist;
757
758 static void
759 set_register_names ()
760 {
761 if (h8300hmode != 0)
762 h8300_register_names = h8300h_register_names;
763 else
764 h8300_register_names = original_register_names;
765 }
766
767 static void
768 h8300_command (args, from_tty)
769 {
770 extern int h8300hmode;
771 h8300hmode = 0;
772 h8300smode = 0;
773 set_register_names ();
774 }
775
776 static void
777 h8300h_command (args, from_tty)
778 {
779 extern int h8300hmode;
780 h8300hmode = 1;
781 h8300smode = 0;
782 set_register_names ();
783 }
784
785 static void
786 h8300s_command (args, from_tty)
787 {
788 extern int h8300smode;
789 extern int h8300hmode;
790 h8300smode = 1;
791 h8300hmode = 1;
792 set_register_names ();
793 }
794
795
796 static void
797 set_machine (args, from_tty)
798 char *args;
799 int from_tty;
800 {
801 printf_unfiltered ("\"set machine\" must be followed by h8300, h8300h");
802 printf_unfiltered ("or h8300s");
803 help_list (setmemorylist, "set memory ", -1, gdb_stdout);
804 }
805
806 /* set_machine_hook is called as the exec file is being opened, but
807 before the symbol file is opened. This allows us to set the
808 h8300hmode flag based on the machine type specified in the exec
809 file. This in turn will cause subsequently defined pointer types
810 to be 16 or 32 bits as appropriate for the machine. */
811
812 static void
813 set_machine_hook (filename)
814 char *filename;
815 {
816 if (bfd_get_mach (exec_bfd) == bfd_mach_h8300s)
817 {
818 h8300smode = 1;
819 h8300hmode = 1;
820 }
821 else if (bfd_get_mach (exec_bfd) == bfd_mach_h8300h)
822 {
823 h8300smode = 0;
824 h8300hmode = 1;
825 }
826 else
827 {
828 h8300smode = 0;
829 h8300hmode = 0;
830 }
831 set_register_names ();
832 }
833
834 void
835 _initialize_h8300m ()
836 {
837 add_prefix_cmd ("machine", no_class, set_machine,
838 "set the machine type",
839 &setmemorylist, "set machine ", 0,
840 &setlist);
841
842 add_cmd ("h8300", class_support, h8300_command,
843 "Set machine to be H8/300.", &setmemorylist);
844
845 add_cmd ("h8300h", class_support, h8300h_command,
846 "Set machine to be H8/300H.", &setmemorylist);
847
848 add_cmd ("h8300s", class_support, h8300s_command,
849 "Set machine to be H8/300S.", &setmemorylist);
850
851 /* Add a hook to set the machine type when we're loading a file. */
852
853 specify_exec_file_hook (set_machine_hook);
854 }
855
856
857
858 void
859 print_register_hook (regno)
860 {
861 if (regno == 8)
862 {
863 /* CCR register */
864 int C, Z, N, V;
865 unsigned char b[4];
866 unsigned char l;
867 read_relative_register_raw_bytes (regno, b);
868 l = b[REGISTER_VIRTUAL_SIZE (8) - 1];
869 printf_unfiltered ("\t");
870 printf_unfiltered ("I-%d - ", (l & 0x80) != 0);
871 printf_unfiltered ("H-%d - ", (l & 0x20) != 0);
872 N = (l & 0x8) != 0;
873 Z = (l & 0x4) != 0;
874 V = (l & 0x2) != 0;
875 C = (l & 0x1) != 0;
876 printf_unfiltered ("N-%d ", N);
877 printf_unfiltered ("Z-%d ", Z);
878 printf_unfiltered ("V-%d ", V);
879 printf_unfiltered ("C-%d ", C);
880 if ((C | Z) == 0)
881 printf_unfiltered ("u> ");
882 if ((C | Z) == 1)
883 printf_unfiltered ("u<= ");
884 if ((C == 0))
885 printf_unfiltered ("u>= ");
886 if (C == 1)
887 printf_unfiltered ("u< ");
888 if (Z == 0)
889 printf_unfiltered ("!= ");
890 if (Z == 1)
891 printf_unfiltered ("== ");
892 if ((N ^ V) == 0)
893 printf_unfiltered (">= ");
894 if ((N ^ V) == 1)
895 printf_unfiltered ("< ");
896 if ((Z | (N ^ V)) == 0)
897 printf_unfiltered ("> ");
898 if ((Z | (N ^ V)) == 1)
899 printf_unfiltered ("<= ");
900 }
901 }
902
903 void
904 _initialize_h8300_tdep ()
905 {
906 tm_print_insn = gdb_print_insn_h8300;
907 }