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c906108c
SS
1/* Target-dependent code for the Matsushita MN10300 for GDB, the GNU debugger.
2 Copyright 1996, 1997, 1998 Free Software Foundation, Inc.
3
4This file is part of GDB.
5
6This program is free software; you can redistribute it and/or modify
7it under the terms of the GNU General Public License as published by
8the Free Software Foundation; either version 2 of the License, or
9(at your option) any later version.
10
11This program is distributed in the hope that it will be useful,
12but WITHOUT ANY WARRANTY; without even the implied warranty of
13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14GNU General Public License for more details.
15
16You should have received a copy of the GNU General Public License
17along with this program; if not, write to the Free Software
18Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
19
20#include "defs.h"
21#include "frame.h"
22#include "inferior.h"
23#include "obstack.h"
24#include "target.h"
25#include "value.h"
26#include "bfd.h"
27#include "gdb_string.h"
28#include "gdbcore.h"
29#include "symfile.h"
30
c906108c
SS
31static CORE_ADDR mn10300_analyze_prologue PARAMS ((struct frame_info *fi,
32 CORE_ADDR pc));
33
34/* Additional info used by the frame */
35
36struct frame_extra_info
37{
38 int status;
39 int stack_size;
40};
41
0f71a2f6
JM
42
43static char *mn10300_generic_register_names[] =
44{ "d0", "d1", "d2", "d3", "a0", "a1", "a2", "a3",
45 "sp", "pc", "mdr", "psw", "lir", "lar", "", "",
46 "", "", "", "", "", "", "", "",
47 "", "", "", "", "", "", "", "fp" };
48
49static char **mn10300_register_names = mn10300_generic_register_names;
50
51char *
52mn10300_register_name (i)
53 int i;
54{
55 return mn10300_register_names[i];
56}
57
58CORE_ADDR
59mn10300_saved_pc_after_call (fi)
60 struct frame_info *fi;
61{
62 return read_memory_integer (read_register (SP_REGNUM), 4);
63}
64
65void
66mn10300_extract_return_value (type, regbuf, valbuf)
67 struct type *type;
68 char *regbuf;
69 char *valbuf;
70{
71 if (TYPE_CODE (type) == TYPE_CODE_PTR)
72 memcpy (valbuf, regbuf + REGISTER_BYTE (4), TYPE_LENGTH (type));
73 else
74 memcpy (valbuf, regbuf + REGISTER_BYTE (0), TYPE_LENGTH (type));
75}
76
77CORE_ADDR
78mn10300_extract_struct_value_address (regbuf)
79 char *regbuf;
80{
81 return extract_address (regbuf + REGISTER_BYTE (4),
82 REGISTER_RAW_SIZE (4));
83}
84
85void
86mn10300_store_return_value (type, valbuf)
87 struct type *type;
88 char *valbuf;
89{
90 if (TYPE_CODE (type) == TYPE_CODE_PTR)
91 write_register_bytes (REGISTER_BYTE (4), valbuf, TYPE_LENGTH (type));
92 else
93 write_register_bytes (REGISTER_BYTE (0), valbuf, TYPE_LENGTH (type));
94}
95
c906108c
SS
96static struct frame_info *analyze_dummy_frame PARAMS ((CORE_ADDR, CORE_ADDR));
97static struct frame_info *
98analyze_dummy_frame (pc, frame)
99 CORE_ADDR pc;
100 CORE_ADDR frame;
101{
102 static struct frame_info *dummy = NULL;
103 if (dummy == NULL)
104 {
105 dummy = xmalloc (sizeof (struct frame_info));
106 dummy->saved_regs = xmalloc (SIZEOF_FRAME_SAVED_REGS);
107 dummy->extra_info = xmalloc (sizeof (struct frame_extra_info));
108 }
109 dummy->next = NULL;
110 dummy->prev = NULL;
111 dummy->pc = pc;
112 dummy->frame = frame;
113 dummy->extra_info->status = 0;
114 dummy->extra_info->stack_size = 0;
115 memset (dummy->saved_regs, '\000', SIZEOF_FRAME_SAVED_REGS);
116 mn10300_analyze_prologue (dummy, 0);
117 return dummy;
118}
119
120/* Values for frame_info.status */
121
122#define MY_FRAME_IN_SP 0x1
123#define MY_FRAME_IN_FP 0x2
124#define NO_MORE_FRAMES 0x4
125
126
127/* Should call_function allocate stack space for a struct return? */
128int
129mn10300_use_struct_convention (gcc_p, type)
130 int gcc_p;
131 struct type *type;
132{
133 return (TYPE_NFIELDS (type) > 1 || TYPE_LENGTH (type) > 8);
134}
135
136/* The breakpoint instruction must be the same size as the smallest
137 instruction in the instruction set.
138
139 The Matsushita mn10x00 processors have single byte instructions
140 so we need a single byte breakpoint. Matsushita hasn't defined
141 one, so we defined it ourselves. */
142
143unsigned char *
144mn10300_breakpoint_from_pc (bp_addr, bp_size)
145 CORE_ADDR *bp_addr;
146 int *bp_size;
147{
148 static char breakpoint[] = {0xff};
149 *bp_size = 1;
150 return breakpoint;
151}
152
153
154/* Fix fi->frame if it's bogus at this point. This is a helper
155 function for mn10300_analyze_prologue. */
156
157static void
158fix_frame_pointer (fi, stack_size)
159 struct frame_info *fi;
160 int stack_size;
161{
162 if (fi && fi->next == NULL)
163 {
164 if (fi->extra_info->status & MY_FRAME_IN_SP)
165 fi->frame = read_sp () - stack_size;
166 else if (fi->extra_info->status & MY_FRAME_IN_FP)
167 fi->frame = read_register (A3_REGNUM);
168 }
169}
170
171
172/* Set offsets of registers saved by movm instruction.
173 This is a helper function for mn10300_analyze_prologue. */
174
175static void
176set_movm_offsets (fi, movm_args)
177 struct frame_info *fi;
178 int movm_args;
179{
180 int offset = 0;
181
182 if (fi == NULL || movm_args == 0)
183 return;
184
185 if (movm_args & 0x10)
186 {
187 fi->saved_regs[A3_REGNUM] = fi->frame + offset;
188 offset += 4;
189 }
190 if (movm_args & 0x20)
191 {
192 fi->saved_regs[A2_REGNUM] = fi->frame + offset;
193 offset += 4;
194 }
195 if (movm_args & 0x40)
196 {
197 fi->saved_regs[D3_REGNUM] = fi->frame + offset;
198 offset += 4;
199 }
200 if (movm_args & 0x80)
201 {
202 fi->saved_regs[D2_REGNUM] = fi->frame + offset;
203 offset += 4;
204 }
205}
206
207
208/* The main purpose of this file is dealing with prologues to extract
209 information about stack frames and saved registers.
210
211 For reference here's how prologues look on the mn10300:
212
213 With frame pointer:
214 movm [d2,d3,a2,a3],sp
215 mov sp,a3
216 add <size>,sp
217
218 Without frame pointer:
219 movm [d2,d3,a2,a3],sp (if needed)
220 add <size>,sp
221
222 One day we might keep the stack pointer constant, that won't
223 change the code for prologues, but it will make the frame
224 pointerless case much more common. */
225
226/* Analyze the prologue to determine where registers are saved,
227 the end of the prologue, etc etc. Return the end of the prologue
228 scanned.
229
230 We store into FI (if non-null) several tidbits of information:
231
232 * stack_size -- size of this stack frame. Note that if we stop in
233 certain parts of the prologue/epilogue we may claim the size of the
234 current frame is zero. This happens when the current frame has
235 not been allocated yet or has already been deallocated.
236
237 * fsr -- Addresses of registers saved in the stack by this frame.
238
239 * status -- A (relatively) generic status indicator. It's a bitmask
240 with the following bits:
241
242 MY_FRAME_IN_SP: The base of the current frame is actually in
243 the stack pointer. This can happen for frame pointerless
244 functions, or cases where we're stopped in the prologue/epilogue
245 itself. For these cases mn10300_analyze_prologue will need up
246 update fi->frame before returning or analyzing the register
247 save instructions.
248
249 MY_FRAME_IN_FP: The base of the current frame is in the
250 frame pointer register ($a2).
251
252 NO_MORE_FRAMES: Set this if the current frame is "start" or
253 if the first instruction looks like mov <imm>,sp. This tells
254 frame chain to not bother trying to unwind past this frame. */
255
256static CORE_ADDR
257mn10300_analyze_prologue (fi, pc)
258 struct frame_info *fi;
259 CORE_ADDR pc;
260{
261 CORE_ADDR func_addr, func_end, addr, stop;
262 CORE_ADDR stack_size;
263 int imm_size;
264 unsigned char buf[4];
265 int status, movm_args = 0;
266 char *name;
267
268 /* Use the PC in the frame if it's provided to look up the
269 start of this function. */
270 pc = (fi ? fi->pc : pc);
271
272 /* Find the start of this function. */
273 status = find_pc_partial_function (pc, &name, &func_addr, &func_end);
274
275 /* Do nothing if we couldn't find the start of this function or if we're
276 stopped at the first instruction in the prologue. */
277 if (status == 0)
278 return pc;
279
280 /* If we're in start, then give up. */
281 if (strcmp (name, "start") == 0)
282 {
283 if (fi != NULL)
284 fi->extra_info->status = NO_MORE_FRAMES;
285 return pc;
286 }
287
288 /* At the start of a function our frame is in the stack pointer. */
289 if (fi)
290 fi->extra_info->status = MY_FRAME_IN_SP;
291
292 /* Get the next two bytes into buf, we need two because rets is a two
293 byte insn and the first isn't enough to uniquely identify it. */
294 status = read_memory_nobpt (pc, buf, 2);
295 if (status != 0)
296 return pc;
297
298 /* If we're physically on an "rets" instruction, then our frame has
299 already been deallocated. Note this can also be true for retf
300 and ret if they specify a size of zero.
301
302 In this case fi->frame is bogus, we need to fix it. */
303 if (fi && buf[0] == 0xf0 && buf[1] == 0xfc)
304 {
305 if (fi->next == NULL)
306 fi->frame = read_sp ();
307 return fi->pc;
308 }
309
310 /* Similarly if we're stopped on the first insn of a prologue as our
311 frame hasn't been allocated yet. */
312 if (fi && fi->pc == func_addr)
313 {
314 if (fi->next == NULL)
315 fi->frame = read_sp ();
316 return fi->pc;
317 }
318
319 /* Figure out where to stop scanning. */
320 stop = fi ? fi->pc : func_end;
321
322 /* Don't walk off the end of the function. */
323 stop = stop > func_end ? func_end : stop;
324
325 /* Start scanning on the first instruction of this function. */
326 addr = func_addr;
327
328 /* Suck in two bytes. */
329 status = read_memory_nobpt (addr, buf, 2);
330 if (status != 0)
331 {
332 fix_frame_pointer (fi, 0);
333 return addr;
334 }
335
336 /* First see if this insn sets the stack pointer; if so, it's something
337 we won't understand, so quit now. */
338 if (buf[0] == 0xf2 && (buf[1] & 0xf3) == 0xf0)
339 {
340 if (fi)
341 fi->extra_info->status = NO_MORE_FRAMES;
342 return addr;
343 }
344
345 /* Now look for movm [regs],sp, which saves the callee saved registers.
346
347 At this time we don't know if fi->frame is valid, so we only note
348 that we encountered a movm instruction. Later, we'll set the entries
349 in fsr.regs as needed. */
350 if (buf[0] == 0xcf)
351 {
352 /* Extract the register list for the movm instruction. */
353 status = read_memory_nobpt (addr + 1, buf, 1);
354 movm_args = *buf;
355
356 addr += 2;
357
358 /* Quit now if we're beyond the stop point. */
359 if (addr >= stop)
360 {
361 /* Fix fi->frame since it's bogus at this point. */
362 if (fi && fi->next == NULL)
363 fi->frame = read_sp ();
364
365 /* Note if/where callee saved registers were saved. */
366 set_movm_offsets (fi, movm_args);
367 return addr;
368 }
369
370 /* Get the next two bytes so the prologue scan can continue. */
371 status = read_memory_nobpt (addr, buf, 2);
372 if (status != 0)
373 {
374 /* Fix fi->frame since it's bogus at this point. */
375 if (fi && fi->next == NULL)
376 fi->frame = read_sp ();
377
378 /* Note if/where callee saved registers were saved. */
379 set_movm_offsets (fi, movm_args);
380 return addr;
381 }
382 }
383
384 /* Now see if we set up a frame pointer via "mov sp,a3" */
385 if (buf[0] == 0x3f)
386 {
387 addr += 1;
388
389 /* The frame pointer is now valid. */
390 if (fi)
391 {
392 fi->extra_info->status |= MY_FRAME_IN_FP;
393 fi->extra_info->status &= ~MY_FRAME_IN_SP;
394 }
395
396 /* Quit now if we're beyond the stop point. */
397 if (addr >= stop)
398 {
399 /* Fix fi->frame if it's bogus at this point. */
400 fix_frame_pointer (fi, 0);
401
402 /* Note if/where callee saved registers were saved. */
403 set_movm_offsets (fi, movm_args);
404 return addr;
405 }
406
407 /* Get two more bytes so scanning can continue. */
408 status = read_memory_nobpt (addr, buf, 2);
409 if (status != 0)
410 {
411 /* Fix fi->frame if it's bogus at this point. */
412 fix_frame_pointer (fi, 0);
413
414 /* Note if/where callee saved registers were saved. */
415 set_movm_offsets (fi, movm_args);
416 return addr;
417 }
418 }
419
420 /* Next we should allocate the local frame. No more prologue insns
421 are found after allocating the local frame.
422
423 Search for add imm8,sp (0xf8feXX)
424 or add imm16,sp (0xfafeXXXX)
425 or add imm32,sp (0xfcfeXXXXXXXX).
426
427 If none of the above was found, then this prologue has no
428 additional stack. */
429
430 status = read_memory_nobpt (addr, buf, 2);
431 if (status != 0)
432 {
433 /* Fix fi->frame if it's bogus at this point. */
434 fix_frame_pointer (fi, 0);
435
436 /* Note if/where callee saved registers were saved. */
437 set_movm_offsets (fi, movm_args);
438 return addr;
439 }
440
441 imm_size = 0;
442 if (buf[0] == 0xf8 && buf[1] == 0xfe)
443 imm_size = 1;
444 else if (buf[0] == 0xfa && buf[1] == 0xfe)
445 imm_size = 2;
446 else if (buf[0] == 0xfc && buf[1] == 0xfe)
447 imm_size = 4;
448
449 if (imm_size != 0)
450 {
451 /* Suck in imm_size more bytes, they'll hold the size of the
452 current frame. */
453 status = read_memory_nobpt (addr + 2, buf, imm_size);
454 if (status != 0)
455 {
456 /* Fix fi->frame if it's bogus at this point. */
457 fix_frame_pointer (fi, 0);
458
459 /* Note if/where callee saved registers were saved. */
460 set_movm_offsets (fi, movm_args);
461 return addr;
462 }
463
464 /* Note the size of the stack in the frame info structure. */
465 stack_size = extract_signed_integer (buf, imm_size);
466 if (fi)
467 fi->extra_info->stack_size = stack_size;
468
469 /* We just consumed 2 + imm_size bytes. */
470 addr += 2 + imm_size;
471
472 /* No more prologue insns follow, so begin preparation to return. */
473 /* Fix fi->frame if it's bogus at this point. */
474 fix_frame_pointer (fi, stack_size);
475
476 /* Note if/where callee saved registers were saved. */
477 set_movm_offsets (fi, movm_args);
478 return addr;
479 }
480
481 /* We never found an insn which allocates local stack space, regardless
482 this is the end of the prologue. */
483 /* Fix fi->frame if it's bogus at this point. */
484 fix_frame_pointer (fi, 0);
485
486 /* Note if/where callee saved registers were saved. */
487 set_movm_offsets (fi, movm_args);
488 return addr;
489}
490
491/* Function: frame_chain
492 Figure out and return the caller's frame pointer given current
493 frame_info struct.
494
495 We don't handle dummy frames yet but we would probably just return the
496 stack pointer that was in use at the time the function call was made? */
497
498CORE_ADDR
499mn10300_frame_chain (fi)
500 struct frame_info *fi;
501{
502 struct frame_info *dummy;
503 /* Walk through the prologue to determine the stack size,
504 location of saved registers, end of the prologue, etc. */
505 if (fi->extra_info->status == 0)
506 mn10300_analyze_prologue (fi, (CORE_ADDR)0);
507
508 /* Quit now if mn10300_analyze_prologue set NO_MORE_FRAMES. */
509 if (fi->extra_info->status & NO_MORE_FRAMES)
510 return 0;
511
512 /* Now that we've analyzed our prologue, determine the frame
513 pointer for our caller.
514
515 If our caller has a frame pointer, then we need to
516 find the entry value of $a3 to our function.
517
518 If fsr.regs[A3_REGNUM] is nonzero, then it's at the memory
519 location pointed to by fsr.regs[A3_REGNUM].
520
521 Else it's still in $a3.
522
523 If our caller does not have a frame pointer, then his
524 frame base is fi->frame + -caller's stack size. */
525
526 /* The easiest way to get that info is to analyze our caller's frame.
527 So we set up a dummy frame and call mn10300_analyze_prologue to
528 find stuff for us. */
529 dummy = analyze_dummy_frame (FRAME_SAVED_PC (fi), fi->frame);
530
531 if (dummy->extra_info->status & MY_FRAME_IN_FP)
532 {
533 /* Our caller has a frame pointer. So find the frame in $a3 or
534 in the stack. */
535 if (fi->saved_regs[A3_REGNUM])
536 return (read_memory_integer (fi->saved_regs[A3_REGNUM], REGISTER_SIZE));
537 else
538 return read_register (A3_REGNUM);
539 }
540 else
541 {
542 int adjust = 0;
543
544 adjust += (fi->saved_regs[D2_REGNUM] ? 4 : 0);
545 adjust += (fi->saved_regs[D3_REGNUM] ? 4 : 0);
546 adjust += (fi->saved_regs[A2_REGNUM] ? 4 : 0);
547 adjust += (fi->saved_regs[A3_REGNUM] ? 4 : 0);
548
549 /* Our caller does not have a frame pointer. So his frame starts
550 at the base of our frame (fi->frame) + register save space
551 + <his size>. */
552 return fi->frame + adjust + -dummy->extra_info->stack_size;
553 }
554}
555
556/* Function: skip_prologue
557 Return the address of the first inst past the prologue of the function. */
558
559CORE_ADDR
560mn10300_skip_prologue (pc)
561 CORE_ADDR pc;
562{
563 /* We used to check the debug symbols, but that can lose if
564 we have a null prologue. */
565 return mn10300_analyze_prologue (NULL, pc);
566}
567
568
569/* Function: pop_frame
570 This routine gets called when either the user uses the `return'
571 command, or the call dummy breakpoint gets hit. */
572
573void
574mn10300_pop_frame (frame)
575 struct frame_info *frame;
576{
577 int regnum;
578
579 if (PC_IN_CALL_DUMMY(frame->pc, frame->frame, frame->frame))
580 generic_pop_dummy_frame ();
581 else
582 {
583 write_register (PC_REGNUM, FRAME_SAVED_PC (frame));
584
585 /* Restore any saved registers. */
586 for (regnum = 0; regnum < NUM_REGS; regnum++)
587 if (frame->saved_regs[regnum] != 0)
588 {
589 ULONGEST value;
590
591 value = read_memory_unsigned_integer (frame->saved_regs[regnum],
592 REGISTER_RAW_SIZE (regnum));
593 write_register (regnum, value);
594 }
595
596 /* Actually cut back the stack. */
597 write_register (SP_REGNUM, FRAME_FP (frame));
598
599 /* Don't we need to set the PC?!? XXX FIXME. */
600 }
601
602 /* Throw away any cached frame information. */
603 flush_cached_frames ();
604}
605
606/* Function: push_arguments
607 Setup arguments for a call to the target. Arguments go in
608 order on the stack. */
609
610CORE_ADDR
611mn10300_push_arguments (nargs, args, sp, struct_return, struct_addr)
612 int nargs;
613 value_ptr *args;
614 CORE_ADDR sp;
615 unsigned char struct_return;
616 CORE_ADDR struct_addr;
617{
618 int argnum = 0;
619 int len = 0;
620 int stack_offset = 0;
621 int regsused = struct_return ? 1 : 0;
622
623 /* This should be a nop, but align the stack just in case something
624 went wrong. Stacks are four byte aligned on the mn10300. */
625 sp &= ~3;
626
627 /* Now make space on the stack for the args.
628
629 XXX This doesn't appear to handle pass-by-invisible reference
630 arguments. */
631 for (argnum = 0; argnum < nargs; argnum++)
632 {
633 int arg_length = (TYPE_LENGTH (VALUE_TYPE (args[argnum])) + 3) & ~3;
634
635 while (regsused < 2 && arg_length > 0)
636 {
637 regsused++;
638 arg_length -= 4;
639 }
640 len += arg_length;
641 }
642
643 /* Allocate stack space. */
644 sp -= len;
645
646 regsused = struct_return ? 1 : 0;
647 /* Push all arguments onto the stack. */
648 for (argnum = 0; argnum < nargs; argnum++)
649 {
650 int len;
651 char *val;
652
653 /* XXX Check this. What about UNIONS? */
654 if (TYPE_CODE (VALUE_TYPE (*args)) == TYPE_CODE_STRUCT
655 && TYPE_LENGTH (VALUE_TYPE (*args)) > 8)
656 {
657 /* XXX Wrong, we want a pointer to this argument. */
658 len = TYPE_LENGTH (VALUE_TYPE (*args));
659 val = (char *)VALUE_CONTENTS (*args);
660 }
661 else
662 {
663 len = TYPE_LENGTH (VALUE_TYPE (*args));
664 val = (char *)VALUE_CONTENTS (*args);
665 }
666
667 while (regsused < 2 && len > 0)
668 {
669 write_register (regsused, extract_unsigned_integer (val, 4));
670 val += 4;
671 len -= 4;
672 regsused++;
673 }
674
675 while (len > 0)
676 {
677 write_memory (sp + stack_offset, val, 4);
678 len -= 4;
679 val += 4;
680 stack_offset += 4;
681 }
682
683 args++;
684 }
685
686 /* Make space for the flushback area. */
687 sp -= 8;
688 return sp;
689}
690
691/* Function: push_return_address (pc)
692 Set up the return address for the inferior function call.
693 Needed for targets where we don't actually execute a JSR/BSR instruction */
694
695CORE_ADDR
696mn10300_push_return_address (pc, sp)
697 CORE_ADDR pc;
698 CORE_ADDR sp;
699{
700 unsigned char buf[4];
701
702 store_unsigned_integer (buf, 4, CALL_DUMMY_ADDRESS ());
703 write_memory (sp - 4, buf, 4);
704 return sp - 4;
705}
706
707/* Function: store_struct_return (addr,sp)
708 Store the structure value return address for an inferior function
709 call. */
710
711CORE_ADDR
712mn10300_store_struct_return (addr, sp)
713 CORE_ADDR addr;
714 CORE_ADDR sp;
715{
716 /* The structure return address is passed as the first argument. */
717 write_register (0, addr);
718 return sp;
719}
720
721/* Function: frame_saved_pc
722 Find the caller of this frame. We do this by seeing if RP_REGNUM
723 is saved in the stack anywhere, otherwise we get it from the
724 registers. If the inner frame is a dummy frame, return its PC
725 instead of RP, because that's where "caller" of the dummy-frame
726 will be found. */
727
728CORE_ADDR
729mn10300_frame_saved_pc (fi)
730 struct frame_info *fi;
731{
732 int adjust = 0;
733
734 adjust += (fi->saved_regs[D2_REGNUM] ? 4 : 0);
735 adjust += (fi->saved_regs[D3_REGNUM] ? 4 : 0);
736 adjust += (fi->saved_regs[A2_REGNUM] ? 4 : 0);
737 adjust += (fi->saved_regs[A3_REGNUM] ? 4 : 0);
738
739 return (read_memory_integer (fi->frame + adjust, REGISTER_SIZE));
740}
741
c906108c
SS
742/* Function: mn10300_init_extra_frame_info
743 Setup the frame's frame pointer, pc, and frame addresses for saved
744 registers. Most of the work is done in mn10300_analyze_prologue().
745
746 Note that when we are called for the last frame (currently active frame),
747 that fi->pc and fi->frame will already be setup. However, fi->frame will
748 be valid only if this routine uses FP. For previous frames, fi-frame will
749 always be correct. mn10300_analyze_prologue will fix fi->frame if
750 it's not valid.
751
752 We can be called with the PC in the call dummy under two circumstances.
753 First, during normal backtracing, second, while figuring out the frame
754 pointer just prior to calling the target function (see run_stack_dummy). */
755
756void
757mn10300_init_extra_frame_info (fi)
758 struct frame_info *fi;
759{
760 if (fi->next)
761 fi->pc = FRAME_SAVED_PC (fi->next);
762
763 frame_saved_regs_zalloc (fi);
764 fi->extra_info = (struct frame_extra_info *)
765 frame_obstack_alloc (sizeof (struct frame_extra_info));
766
767 fi->extra_info->status = 0;
768 fi->extra_info->stack_size = 0;
769
770 mn10300_analyze_prologue (fi, 0);
771}
772
773/* Function: mn10300_virtual_frame_pointer
774 Return the register that the function uses for a frame pointer,
775 plus any necessary offset to be applied to the register before
776 any frame pointer offsets. */
777
778void
779mn10300_virtual_frame_pointer (pc, reg, offset)
780 CORE_ADDR pc;
781 long *reg;
782 long *offset;
783{
784 struct frame_info *dummy = analyze_dummy_frame (pc, 0);
785 /* Set up a dummy frame_info, Analyze the prolog and fill in the
786 extra info. */
787 /* Results will tell us which type of frame it uses. */
788 if (dummy->extra_info->status & MY_FRAME_IN_SP)
789 {
790 *reg = SP_REGNUM;
791 *offset = -(dummy->extra_info->stack_size);
792 }
793 else
794 {
795 *reg = A3_REGNUM;
796 *offset = 0;
797 }
798}
799
800/* This can be made more generic later. */
801static void
802set_machine_hook (filename)
803 char *filename;
804{
805 int i;
806
807 if (bfd_get_mach (exec_bfd) == bfd_mach_mn10300
808 || bfd_get_mach (exec_bfd) == 0)
809 {
810 mn10300_register_names = mn10300_generic_register_names;
811 }
812
813}
814
815void
816_initialize_mn10300_tdep ()
817{
818/* printf("_initialize_mn10300_tdep\n"); */
819
820 tm_print_insn = print_insn_mn10300;
821
822 specify_exec_file_hook (set_machine_hook);
823}
824