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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 | ||
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, 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 |
31 | static CORE_ADDR mn10300_analyze_prologue PARAMS ((struct frame_info *fi, |
32 | CORE_ADDR pc)); | |
33 | ||
34 | /* Additional info used by the frame */ | |
35 | ||
36 | struct frame_extra_info | |
37 | { | |
38 | int status; | |
39 | int stack_size; | |
40 | }; | |
41 | ||
0f71a2f6 JM |
42 | |
43 | static 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 | ||
49 | static char **mn10300_register_names = mn10300_generic_register_names; | |
50 | ||
51 | char * | |
52 | mn10300_register_name (i) | |
53 | int i; | |
54 | { | |
55 | return mn10300_register_names[i]; | |
56 | } | |
57 | ||
58 | CORE_ADDR | |
59 | mn10300_saved_pc_after_call (fi) | |
60 | struct frame_info *fi; | |
61 | { | |
62 | return read_memory_integer (read_register (SP_REGNUM), 4); | |
63 | } | |
64 | ||
65 | void | |
66 | mn10300_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 | ||
77 | CORE_ADDR | |
78 | mn10300_extract_struct_value_address (regbuf) | |
79 | char *regbuf; | |
80 | { | |
81 | return extract_address (regbuf + REGISTER_BYTE (4), | |
82 | REGISTER_RAW_SIZE (4)); | |
83 | } | |
84 | ||
85 | void | |
86 | mn10300_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 |
96 | static struct frame_info *analyze_dummy_frame PARAMS ((CORE_ADDR, CORE_ADDR)); |
97 | static struct frame_info * | |
98 | analyze_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? */ | |
128 | int | |
129 | mn10300_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 | ||
143 | unsigned char * | |
144 | mn10300_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 | ||
157 | static void | |
158 | fix_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 | ||
175 | static void | |
176 | set_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 | ||
256 | static CORE_ADDR | |
257 | mn10300_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 | ||
498 | CORE_ADDR | |
499 | mn10300_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 | ||
559 | CORE_ADDR | |
560 | mn10300_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 | ||
573 | void | |
574 | mn10300_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 | ||
610 | CORE_ADDR | |
611 | mn10300_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 | ||
695 | CORE_ADDR | |
696 | mn10300_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 | ||
711 | CORE_ADDR | |
712 | mn10300_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 | ||
728 | CORE_ADDR | |
729 | mn10300_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 | ||
756 | void | |
757 | mn10300_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 | ||
778 | void | |
779 | mn10300_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. */ | |
801 | static void | |
802 | set_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 | ||
815 | void | |
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 |