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c906108c SS |
1 | /* Target-dependent code for the Fujitsu FR30. |
2 | Copyright 1999, 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 | ||
392a587b JM |
31 | /* An expression that tells us whether the function invocation represented |
32 | by FI does not have a frame on the stack associated with it. */ | |
33 | int | |
34 | fr30_frameless_function_invocation (fi) | |
35 | struct frame_info *fi; | |
36 | { | |
37 | int frameless; | |
38 | CORE_ADDR func_start, after_prologue; | |
39 | func_start = (get_pc_function_start ((fi)->pc) + | |
40 | FUNCTION_START_OFFSET); | |
41 | after_prologue = func_start; | |
42 | after_prologue = SKIP_PROLOGUE (after_prologue); | |
43 | frameless = (after_prologue == func_start); | |
44 | return frameless; | |
45 | } | |
46 | ||
c906108c SS |
47 | /* Function: pop_frame |
48 | This routine gets called when either the user uses the `return' | |
49 | command, or the call dummy breakpoint gets hit. */ | |
50 | ||
51 | void | |
52 | fr30_pop_frame () | |
53 | { | |
54 | struct frame_info *frame = get_current_frame(); | |
55 | int regnum; | |
56 | CORE_ADDR sp = read_register(SP_REGNUM); | |
57 | ||
58 | if (PC_IN_CALL_DUMMY(frame->pc, frame->frame, frame->frame)) | |
59 | generic_pop_dummy_frame (); | |
60 | else | |
61 | { | |
62 | write_register (PC_REGNUM, FRAME_SAVED_PC (frame)); | |
63 | ||
64 | for (regnum = 0; regnum < NUM_REGS; regnum++) | |
65 | if (frame->fsr.regs[regnum] != 0) { | |
66 | write_register (regnum, | |
67 | read_memory_unsigned_integer (frame->fsr.regs[regnum], | |
68 | REGISTER_RAW_SIZE(regnum))); | |
69 | } | |
70 | write_register (SP_REGNUM, sp + frame->framesize); | |
71 | } | |
72 | flush_cached_frames (); | |
73 | } | |
74 | ||
7a292a7a SS |
75 | |
76 | /* Function: fr30_store_return_value | |
77 | Put a value where a caller expects to see it. Used by the 'return' | |
78 | command. */ | |
79 | void | |
80 | fr30_store_return_value (struct type *type, | |
81 | char *valbuf) | |
82 | { | |
83 | /* Here's how the FR30 returns values (gleaned from gcc/config/ | |
84 | fr30/fr30.h): | |
85 | ||
86 | If the return value is 32 bits long or less, it goes in r4. | |
87 | ||
88 | If the return value is 64 bits long or less, it goes in r4 (most | |
89 | significant word) and r5 (least significant word. | |
90 | ||
91 | If the function returns a structure, of any size, the caller | |
92 | passes the function an invisible first argument where the callee | |
93 | should store the value. But GDB doesn't let you do that anyway. | |
94 | ||
95 | If you're returning a value smaller than a word, it's not really | |
96 | necessary to zero the upper bytes of the register; the caller is | |
97 | supposed to ignore them. However, the FR30 typically keeps its | |
98 | values extended to the full register width, so we should emulate | |
99 | that. */ | |
100 | ||
101 | /* The FR30 is big-endian, so if we return a small value (like a | |
102 | short or a char), we need to position it correctly within the | |
103 | register. We round the size up to a register boundary, and then | |
104 | adjust the offset so as to place the value at the right end. */ | |
105 | int value_size = TYPE_LENGTH (type); | |
106 | int returned_size = (value_size + FR30_REGSIZE - 1) & ~(FR30_REGSIZE - 1); | |
107 | int offset = (REGISTER_BYTE (RETVAL_REG) | |
108 | + (returned_size - value_size)); | |
109 | char *zeros = alloca (returned_size); | |
110 | memset (zeros, 0, returned_size); | |
111 | ||
112 | write_register_bytes (REGISTER_BYTE (RETVAL_REG), zeros, returned_size); | |
113 | write_register_bytes (offset, valbuf, value_size); | |
114 | } | |
115 | ||
116 | ||
c906108c SS |
117 | /* Function: skip_prologue |
118 | Return the address of the first code past the prologue of the function. */ | |
119 | ||
120 | CORE_ADDR | |
121 | fr30_skip_prologue(CORE_ADDR pc) | |
122 | { | |
123 | CORE_ADDR func_addr, func_end; | |
124 | ||
125 | /* See what the symbol table says */ | |
126 | ||
127 | if (find_pc_partial_function (pc, NULL, &func_addr, &func_end)) | |
128 | { | |
129 | struct symtab_and_line sal; | |
130 | ||
131 | sal = find_pc_line (func_addr, 0); | |
132 | ||
133 | if (sal.line != 0 && sal.end < func_end) { | |
134 | return sal.end; | |
135 | } | |
136 | } | |
137 | ||
138 | /* Either we didn't find the start of this function (nothing we can do), | |
139 | or there's no line info, or the line after the prologue is after | |
140 | the end of the function (there probably isn't a prologue). */ | |
141 | ||
142 | return pc; | |
143 | } | |
144 | ||
145 | ||
146 | /* Function: push_arguments | |
147 | Setup arguments and RP for a call to the target. First four args | |
148 | go in FIRST_ARGREG -> LAST_ARGREG, subsequent args go on stack... | |
149 | Structs are passed by reference. XXX not right now Z.R. | |
150 | 64 bit quantities (doubles and long longs) may be split between | |
151 | the regs and the stack. | |
152 | When calling a function that returns a struct, a pointer to the struct | |
153 | is passed in as a secret first argument (always in FIRST_ARGREG). | |
154 | ||
155 | Stack space for the args has NOT been allocated: that job is up to us. | |
156 | */ | |
157 | ||
158 | CORE_ADDR | |
159 | fr30_push_arguments(nargs, args, sp, struct_return, struct_addr) | |
160 | int nargs; | |
161 | value_ptr * args; | |
162 | CORE_ADDR sp; | |
163 | int struct_return; | |
164 | CORE_ADDR struct_addr; | |
165 | { | |
166 | int argreg; | |
167 | int argnum; | |
168 | int stack_offset; | |
169 | struct stack_arg { | |
170 | char *val; | |
171 | int len; | |
172 | int offset; | |
173 | }; | |
174 | struct stack_arg *stack_args = | |
175 | (struct stack_arg*)alloca (nargs * sizeof (struct stack_arg)); | |
176 | int nstack_args = 0; | |
177 | ||
178 | argreg = FIRST_ARGREG; | |
179 | ||
180 | /* the struct_return pointer occupies the first parameter-passing reg */ | |
181 | if (struct_return) | |
182 | write_register (argreg++, struct_addr); | |
183 | ||
184 | stack_offset = 0; | |
185 | ||
186 | /* Process args from left to right. Store as many as allowed in | |
187 | registers, save the rest to be pushed on the stack */ | |
188 | for(argnum = 0; argnum < nargs; argnum++) | |
189 | { | |
190 | char * val; | |
191 | value_ptr arg = args[argnum]; | |
192 | struct type * arg_type = check_typedef (VALUE_TYPE (arg)); | |
193 | struct type * target_type = TYPE_TARGET_TYPE (arg_type); | |
194 | int len = TYPE_LENGTH (arg_type); | |
195 | enum type_code typecode = TYPE_CODE (arg_type); | |
196 | CORE_ADDR regval; | |
197 | int newarg; | |
198 | ||
199 | val = (char *) VALUE_CONTENTS (arg); | |
200 | ||
201 | { | |
202 | /* Copy the argument to general registers or the stack in | |
203 | register-sized pieces. Large arguments are split between | |
204 | registers and stack. */ | |
205 | while (len > 0) | |
206 | { | |
207 | if (argreg <= LAST_ARGREG) | |
208 | { | |
209 | int partial_len = len < REGISTER_SIZE ? len : REGISTER_SIZE; | |
210 | regval = extract_address (val, partial_len); | |
211 | ||
212 | /* It's a simple argument being passed in a general | |
213 | register. */ | |
214 | write_register (argreg, regval); | |
215 | argreg++; | |
216 | len -= partial_len; | |
217 | val += partial_len; | |
218 | } | |
219 | else | |
220 | { | |
221 | /* keep for later pushing */ | |
222 | stack_args[nstack_args].val = val; | |
223 | stack_args[nstack_args++].len = len; | |
224 | break; | |
225 | } | |
226 | } | |
227 | } | |
228 | } | |
229 | /* now do the real stack pushing, process args right to left */ | |
230 | while(nstack_args--) | |
231 | { | |
232 | sp -= stack_args[nstack_args].len; | |
233 | write_memory(sp, stack_args[nstack_args].val, | |
234 | stack_args[nstack_args].len); | |
235 | } | |
236 | ||
237 | /* Return adjusted stack pointer. */ | |
238 | return sp; | |
239 | } | |
240 | ||
7a292a7a | 241 | void _initialize_fr30_tdep PARAMS ((void)); |
c906108c | 242 | |
7a292a7a SS |
243 | void |
244 | _initialize_fr30_tdep () | |
245 | { | |
246 | extern int print_insn_fr30(bfd_vma, disassemble_info *); | |
247 | tm_print_insn = print_insn_fr30; | |
c906108c SS |
248 | } |
249 | ||
250 | /* Function: check_prologue_cache | |
251 | Check if prologue for this frame's PC has already been scanned. | |
252 | If it has, copy the relevant information about that prologue and | |
253 | return non-zero. Otherwise do not copy anything and return zero. | |
254 | ||
255 | The information saved in the cache includes: | |
256 | * the frame register number; | |
257 | * the size of the stack frame; | |
258 | * the offsets of saved regs (relative to the old SP); and | |
259 | * the offset from the stack pointer to the frame pointer | |
260 | ||
261 | The cache contains only one entry, since this is adequate | |
262 | for the typical sequence of prologue scan requests we get. | |
263 | When performing a backtrace, GDB will usually ask to scan | |
264 | the same function twice in a row (once to get the frame chain, | |
265 | and once to fill in the extra frame information). | |
266 | */ | |
267 | ||
268 | static struct frame_info prologue_cache; | |
269 | ||
270 | static int | |
271 | check_prologue_cache (fi) | |
272 | struct frame_info * fi; | |
273 | { | |
274 | int i; | |
275 | ||
276 | if (fi->pc == prologue_cache.pc) | |
277 | { | |
278 | fi->framereg = prologue_cache.framereg; | |
279 | fi->framesize = prologue_cache.framesize; | |
280 | fi->frameoffset = prologue_cache.frameoffset; | |
281 | for (i = 0; i <= NUM_REGS; i++) | |
282 | fi->fsr.regs[i] = prologue_cache.fsr.regs[i]; | |
283 | return 1; | |
284 | } | |
285 | else | |
286 | return 0; | |
287 | } | |
288 | ||
289 | ||
290 | /* Function: save_prologue_cache | |
291 | Copy the prologue information from fi to the prologue cache. | |
292 | */ | |
293 | ||
294 | static void | |
295 | save_prologue_cache (fi) | |
296 | struct frame_info * fi; | |
297 | { | |
298 | int i; | |
299 | ||
300 | prologue_cache.pc = fi->pc; | |
301 | prologue_cache.framereg = fi->framereg; | |
302 | prologue_cache.framesize = fi->framesize; | |
303 | prologue_cache.frameoffset = fi->frameoffset; | |
304 | ||
305 | for (i = 0; i <= NUM_REGS; i++) { | |
306 | prologue_cache.fsr.regs[i] = fi->fsr.regs[i]; | |
307 | } | |
308 | } | |
309 | ||
310 | ||
311 | /* Function: scan_prologue | |
312 | Scan the prologue of the function that contains PC, and record what | |
313 | we find in PI. PI->fsr must be zeroed by the called. Returns the | |
314 | pc after the prologue. Note that the addresses saved in pi->fsr | |
315 | are actually just frame relative (negative offsets from the frame | |
316 | pointer). This is because we don't know the actual value of the | |
317 | frame pointer yet. In some circumstances, the frame pointer can't | |
318 | be determined till after we have scanned the prologue. */ | |
319 | ||
320 | static void | |
321 | fr30_scan_prologue (fi) | |
322 | struct frame_info * fi; | |
323 | { | |
324 | int sp_offset, fp_offset; | |
325 | CORE_ADDR prologue_start, prologue_end, current_pc; | |
326 | ||
327 | /* Check if this function is already in the cache of frame information. */ | |
328 | if (check_prologue_cache (fi)) | |
329 | return; | |
330 | ||
331 | /* Assume there is no frame until proven otherwise. */ | |
332 | fi->framereg = SP_REGNUM; | |
333 | fi->framesize = 0; | |
334 | fi->frameoffset = 0; | |
335 | ||
336 | /* Find the function prologue. If we can't find the function in | |
337 | the symbol table, peek in the stack frame to find the PC. */ | |
338 | if (find_pc_partial_function (fi->pc, NULL, &prologue_start, &prologue_end)) | |
339 | { | |
340 | /* Assume the prologue is everything between the first instruction | |
341 | in the function and the first source line. */ | |
342 | struct symtab_and_line sal = find_pc_line (prologue_start, 0); | |
343 | ||
344 | if (sal.line == 0) /* no line info, use current PC */ | |
345 | prologue_end = fi->pc; | |
346 | else if (sal.end < prologue_end) /* next line begins after fn end */ | |
347 | prologue_end = sal.end; /* (probably means no prologue) */ | |
348 | } | |
349 | else | |
350 | { | |
351 | /* XXX Z.R. What now??? The following is entirely bogus */ | |
352 | prologue_start = (read_memory_integer (fi->frame, 4) & 0x03fffffc) - 12; | |
353 | prologue_end = prologue_start + 40; | |
354 | } | |
355 | ||
356 | /* Now search the prologue looking for instructions that set up the | |
357 | frame pointer, adjust the stack pointer, and save registers. */ | |
358 | ||
359 | sp_offset = fp_offset = 0; | |
360 | for (current_pc = prologue_start; current_pc < prologue_end; current_pc += 2) | |
361 | { | |
362 | unsigned int insn; | |
363 | ||
364 | insn = read_memory_unsigned_integer (current_pc, 2); | |
365 | ||
366 | if ((insn & 0xfe00) == 0x8e00) /* stm0 or stm1 */ | |
367 | { | |
368 | int reg, mask = insn & 0xff; | |
369 | ||
370 | /* scan in one sweep - create virtual 16-bit mask from either insn's mask */ | |
371 | if((insn & 0x0100) == 0) | |
372 | { | |
373 | mask <<= 8; /* stm0 - move to upper byte in virtual mask */ | |
374 | } | |
375 | ||
376 | /* Calculate offsets of saved registers (to be turned later into addresses). */ | |
377 | for (reg = R4_REGNUM; reg <= R11_REGNUM; reg++) | |
378 | if (mask & (1 << (15 - reg))) | |
379 | { | |
380 | sp_offset -= 4; | |
381 | fi->fsr.regs[reg] = sp_offset; | |
382 | } | |
383 | } | |
384 | else if((insn & 0xfff0) == 0x1700) /* st rx,@-r15 */ | |
385 | { | |
386 | int reg = insn & 0xf; | |
387 | ||
388 | sp_offset -= 4; | |
389 | fi->fsr.regs[reg] = sp_offset; | |
390 | } | |
391 | else if((insn & 0xff00) == 0x0f00) /* enter */ | |
392 | { | |
393 | fp_offset = fi->fsr.regs[FP_REGNUM] = sp_offset - 4; | |
394 | sp_offset -= 4 * (insn & 0xff); | |
395 | fi->framereg = FP_REGNUM; | |
396 | } | |
397 | else if(insn == 0x1781) /* st rp,@-sp */ | |
398 | { | |
399 | sp_offset -= 4; | |
400 | fi->fsr.regs[RP_REGNUM] = sp_offset; | |
401 | } | |
402 | else if(insn == 0x170e) /* st fp,@-sp */ | |
403 | { | |
404 | sp_offset -= 4; | |
405 | fi->fsr.regs[FP_REGNUM] = sp_offset; | |
406 | } | |
407 | else if(insn == 0x8bfe) /* mov sp,fp */ | |
408 | { | |
409 | fi->framereg = FP_REGNUM; | |
410 | } | |
411 | else if((insn & 0xff00) == 0xa300) /* addsp xx */ | |
412 | { | |
413 | sp_offset += 4 * (signed char)(insn & 0xff); | |
414 | } | |
415 | else if((insn & 0xff0f) == 0x9b00 && /* ldi:20 xx,r0 */ | |
416 | read_memory_unsigned_integer(current_pc+4, 2) | |
417 | == 0xac0f) /* sub r0,sp */ | |
418 | { | |
419 | /* large stack adjustment */ | |
420 | sp_offset -= (((insn & 0xf0) << 12) | read_memory_unsigned_integer(current_pc+2, 2)); | |
421 | current_pc += 4; | |
422 | } | |
423 | else if(insn == 0x9f80 && /* ldi:32 xx,r0 */ | |
424 | read_memory_unsigned_integer(current_pc+6, 2) | |
425 | == 0xac0f) /* sub r0,sp */ | |
426 | { | |
427 | /* large stack adjustment */ | |
428 | sp_offset -= | |
429 | (read_memory_unsigned_integer(current_pc+2, 2) << 16 | | |
430 | read_memory_unsigned_integer(current_pc+4, 2)); | |
431 | current_pc += 6; | |
432 | } | |
433 | } | |
434 | ||
435 | /* The frame size is just the negative of the offset (from the original SP) | |
436 | of the last thing thing we pushed on the stack. The frame offset is | |
437 | [new FP] - [new SP]. */ | |
438 | fi->framesize = -sp_offset; | |
439 | fi->frameoffset = fp_offset - sp_offset; | |
440 | ||
441 | save_prologue_cache (fi); | |
442 | } | |
443 | ||
444 | /* Function: init_extra_frame_info | |
445 | Setup the frame's frame pointer, pc, and frame addresses for saved | |
446 | registers. Most of the work is done in scan_prologue(). | |
447 | ||
448 | Note that when we are called for the last frame (currently active frame), | |
449 | that fi->pc and fi->frame will already be setup. However, fi->frame will | |
450 | be valid only if this routine uses FP. For previous frames, fi-frame will | |
451 | always be correct (since that is derived from fr30_frame_chain ()). | |
452 | ||
453 | We can be called with the PC in the call dummy under two circumstances. | |
454 | First, during normal backtracing, second, while figuring out the frame | |
455 | pointer just prior to calling the target function (see run_stack_dummy). */ | |
456 | ||
457 | void | |
458 | fr30_init_extra_frame_info (fi) | |
459 | struct frame_info * fi; | |
460 | { | |
461 | int reg; | |
462 | ||
463 | if (fi->next) | |
464 | fi->pc = FRAME_SAVED_PC (fi->next); | |
465 | ||
466 | memset (fi->fsr.regs, '\000', sizeof fi->fsr.regs); | |
467 | ||
468 | if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) | |
469 | { | |
470 | /* We need to setup fi->frame here because run_stack_dummy gets it wrong | |
471 | by assuming it's always FP. */ | |
472 | fi->frame = generic_read_register_dummy (fi->pc, fi->frame, SP_REGNUM); | |
473 | fi->framesize = 0; | |
474 | fi->frameoffset = 0; | |
475 | return; | |
476 | } | |
477 | fr30_scan_prologue (fi); | |
478 | ||
479 | if (!fi->next) /* this is the innermost frame? */ | |
480 | fi->frame = read_register (fi->framereg); | |
481 | else /* not the innermost frame */ | |
482 | /* If we have an FP, the callee saved it. */ | |
483 | if (fi->framereg == FP_REGNUM) | |
484 | if (fi->next->fsr.regs[fi->framereg] != 0) | |
485 | fi->frame = read_memory_integer (fi->next->fsr.regs[fi->framereg], | |
486 | 4); | |
487 | /* Calculate actual addresses of saved registers using offsets determined | |
488 | by fr30_scan_prologue. */ | |
489 | for (reg = 0; reg < NUM_REGS; reg++) | |
490 | if (fi->fsr.regs[reg] != 0) { | |
491 | fi->fsr.regs[reg] += fi->frame + fi->framesize - fi->frameoffset; | |
492 | } | |
493 | } | |
494 | ||
495 | /* Function: find_callers_reg | |
496 | Find REGNUM on the stack. Otherwise, it's in an active register. | |
497 | One thing we might want to do here is to check REGNUM against the | |
498 | clobber mask, and somehow flag it as invalid if it isn't saved on | |
499 | the stack somewhere. This would provide a graceful failure mode | |
500 | when trying to get the value of caller-saves registers for an inner | |
501 | frame. */ | |
502 | ||
503 | CORE_ADDR | |
504 | fr30_find_callers_reg (fi, regnum) | |
505 | struct frame_info *fi; | |
506 | int regnum; | |
507 | { | |
508 | for (; fi; fi = fi->next) | |
509 | if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) | |
510 | return generic_read_register_dummy (fi->pc, fi->frame, regnum); | |
511 | else if (fi->fsr.regs[regnum] != 0) | |
512 | return read_memory_unsigned_integer (fi->fsr.regs[regnum], | |
513 | REGISTER_RAW_SIZE(regnum)); | |
514 | ||
515 | return read_register (regnum); | |
516 | } | |
517 | ||
518 | ||
519 | /* Function: frame_chain | |
520 | Figure out the frame prior to FI. Unfortunately, this involves | |
521 | scanning the prologue of the caller, which will also be done | |
522 | shortly by fr30_init_extra_frame_info. For the dummy frame, we | |
523 | just return the stack pointer that was in use at the time the | |
524 | function call was made. */ | |
525 | ||
526 | ||
527 | CORE_ADDR | |
528 | fr30_frame_chain (fi) | |
529 | struct frame_info * fi; | |
530 | { | |
531 | CORE_ADDR fn_start, callers_pc, fp; | |
532 | struct frame_info caller_fi; | |
533 | int framereg; | |
534 | ||
535 | /* is this a dummy frame? */ | |
536 | if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) | |
537 | return fi->frame; /* dummy frame same as caller's frame */ | |
538 | ||
539 | /* is caller-of-this a dummy frame? */ | |
540 | callers_pc = FRAME_SAVED_PC(fi); /* find out who called us: */ | |
541 | fp = fr30_find_callers_reg (fi, FP_REGNUM); | |
542 | if (PC_IN_CALL_DUMMY (callers_pc, fp, fp)) | |
543 | return fp; /* dummy frame's frame may bear no relation to ours */ | |
544 | ||
545 | if (find_pc_partial_function (fi->pc, 0, &fn_start, 0)) | |
546 | if (fn_start == entry_point_address ()) | |
547 | return 0; /* in _start fn, don't chain further */ | |
548 | ||
549 | framereg = fi->framereg; | |
550 | ||
551 | /* If the caller is the startup code, we're at the end of the chain. */ | |
552 | if (find_pc_partial_function (callers_pc, 0, &fn_start, 0)) | |
553 | if (fn_start == entry_point_address ()) | |
554 | return 0; | |
555 | ||
556 | memset (& caller_fi, 0, sizeof (caller_fi)); | |
557 | caller_fi.pc = callers_pc; | |
558 | fr30_scan_prologue (& caller_fi); | |
559 | framereg = caller_fi.framereg; | |
560 | ||
561 | /* If the caller used a frame register, return its value. | |
562 | Otherwise, return the caller's stack pointer. */ | |
563 | if (framereg == FP_REGNUM) | |
564 | return fr30_find_callers_reg (fi, framereg); | |
565 | else | |
566 | return fi->frame + fi->framesize; | |
567 | } | |
568 | ||
569 | /* Function: frame_saved_pc | |
570 | Find the caller of this frame. We do this by seeing if RP_REGNUM | |
571 | is saved in the stack anywhere, otherwise we get it from the | |
572 | registers. If the inner frame is a dummy frame, return its PC | |
573 | instead of RP, because that's where "caller" of the dummy-frame | |
574 | will be found. */ | |
575 | ||
576 | CORE_ADDR | |
577 | fr30_frame_saved_pc (fi) | |
578 | struct frame_info *fi; | |
579 | { | |
580 | if (PC_IN_CALL_DUMMY(fi->pc, fi->frame, fi->frame)) | |
581 | return generic_read_register_dummy(fi->pc, fi->frame, PC_REGNUM); | |
582 | else | |
583 | return fr30_find_callers_reg (fi, RP_REGNUM); | |
584 | } | |
585 | ||
586 | /* Function: fix_call_dummy | |
587 | Pokes the callee function's address into the CALL_DUMMY assembly stub. | |
588 | Assumes that the CALL_DUMMY looks like this: | |
589 | jarl <offset24>, r31 | |
590 | trap | |
591 | */ | |
592 | ||
593 | int | |
594 | fr30_fix_call_dummy (dummy, sp, fun, nargs, args, type, gcc_p) | |
595 | char *dummy; | |
596 | CORE_ADDR sp; | |
597 | CORE_ADDR fun; | |
598 | int nargs; | |
599 | value_ptr *args; | |
600 | struct type *type; | |
601 | int gcc_p; | |
602 | { | |
603 | long offset24; | |
604 | ||
605 | offset24 = (long) fun - (long) entry_point_address (); | |
606 | offset24 &= 0x3fffff; | |
607 | offset24 |= 0xff800000; /* jarl <offset24>, r31 */ | |
608 | ||
609 | store_unsigned_integer ((unsigned int *)&dummy[2], 2, offset24 & 0xffff); | |
610 | store_unsigned_integer ((unsigned int *)&dummy[0], 2, offset24 >> 16); | |
611 | return 0; | |
612 | } |