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