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c906108c SS |
1 | /* Get info from stack frames; |
2 | convert between frames, blocks, functions and pc values. | |
3 | Copyright 1986, 87, 88, 89, 91, 94, 95, 96, 97, 1998 | |
c5aa993b | 4 | Free Software Foundation, Inc. |
c906108c | 5 | |
c5aa993b | 6 | This file is part of GDB. |
c906108c | 7 | |
c5aa993b JM |
8 | This program is free software; you can redistribute it and/or modify |
9 | it under the terms of the GNU General Public License as published by | |
10 | the Free Software Foundation; either version 2 of the License, or | |
11 | (at your option) any later version. | |
c906108c | 12 | |
c5aa993b JM |
13 | This program is distributed in the hope that it will be useful, |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
c906108c | 17 | |
c5aa993b JM |
18 | You should have received a copy of the GNU General Public License |
19 | along with this program; if not, write to the Free Software | |
20 | Foundation, Inc., 59 Temple Place - Suite 330, | |
21 | Boston, MA 02111-1307, USA. */ | |
c906108c SS |
22 | |
23 | #include "defs.h" | |
24 | #include "symtab.h" | |
25 | #include "bfd.h" | |
26 | #include "symfile.h" | |
27 | #include "objfiles.h" | |
28 | #include "frame.h" | |
29 | #include "gdbcore.h" | |
30 | #include "value.h" /* for read_register */ | |
31 | #include "target.h" /* for target_has_stack */ | |
32 | #include "inferior.h" /* for read_pc */ | |
33 | #include "annotate.h" | |
34 | ||
35 | /* Prototypes for exported functions. */ | |
36 | ||
37 | void _initialize_blockframe PARAMS ((void)); | |
38 | ||
39 | /* A default FRAME_CHAIN_VALID, in the form that is suitable for most | |
40 | targets. If FRAME_CHAIN_VALID returns zero it means that the given | |
41 | frame is the outermost one and has no caller. */ | |
42 | ||
43 | int | |
44 | default_frame_chain_valid (chain, thisframe) | |
45 | CORE_ADDR chain; | |
46 | struct frame_info *thisframe; | |
47 | { | |
48 | return ((chain) != 0 | |
c5aa993b JM |
49 | && !inside_main_func ((thisframe)->pc) |
50 | && !inside_entry_func ((thisframe)->pc)); | |
c906108c SS |
51 | } |
52 | ||
53 | /* Use the alternate method of avoiding running up off the end of the | |
54 | frame chain or following frames back into the startup code. See | |
55 | the comments in objfiles.h. */ | |
c5aa993b | 56 | |
c906108c SS |
57 | int |
58 | alternate_frame_chain_valid (chain, thisframe) | |
59 | CORE_ADDR chain; | |
60 | struct frame_info *thisframe; | |
61 | { | |
62 | return ((chain) != 0 | |
63 | && !inside_entry_file (FRAME_SAVED_PC (thisframe))); | |
64 | } | |
65 | ||
66 | /* A very simple method of determining a valid frame */ | |
c5aa993b | 67 | |
c906108c SS |
68 | int |
69 | nonnull_frame_chain_valid (chain, thisframe) | |
70 | CORE_ADDR chain; | |
71 | struct frame_info *thisframe; | |
72 | { | |
73 | return ((chain) != 0); | |
74 | } | |
75 | ||
76 | /* Is ADDR inside the startup file? Note that if your machine | |
77 | has a way to detect the bottom of the stack, there is no need | |
78 | to call this function from FRAME_CHAIN_VALID; the reason for | |
79 | doing so is that some machines have no way of detecting bottom | |
80 | of stack. | |
81 | ||
82 | A PC of zero is always considered to be the bottom of the stack. */ | |
83 | ||
84 | int | |
85 | inside_entry_file (addr) | |
86 | CORE_ADDR addr; | |
87 | { | |
88 | if (addr == 0) | |
89 | return 1; | |
90 | if (symfile_objfile == 0) | |
91 | return 0; | |
7a292a7a SS |
92 | if (CALL_DUMMY_LOCATION == AT_ENTRY_POINT) |
93 | { | |
94 | /* Do not stop backtracing if the pc is in the call dummy | |
c5aa993b | 95 | at the entry point. */ |
7a292a7a | 96 | /* FIXME: Won't always work with zeros for the last two arguments */ |
c5aa993b | 97 | if (PC_IN_CALL_DUMMY (addr, 0, 0)) |
7a292a7a SS |
98 | return 0; |
99 | } | |
c5aa993b JM |
100 | return (addr >= symfile_objfile->ei.entry_file_lowpc && |
101 | addr < symfile_objfile->ei.entry_file_highpc); | |
c906108c SS |
102 | } |
103 | ||
104 | /* Test a specified PC value to see if it is in the range of addresses | |
105 | that correspond to the main() function. See comments above for why | |
106 | we might want to do this. | |
107 | ||
108 | Typically called from FRAME_CHAIN_VALID. | |
109 | ||
110 | A PC of zero is always considered to be the bottom of the stack. */ | |
111 | ||
112 | int | |
113 | inside_main_func (pc) | |
c5aa993b | 114 | CORE_ADDR pc; |
c906108c SS |
115 | { |
116 | if (pc == 0) | |
117 | return 1; | |
118 | if (symfile_objfile == 0) | |
119 | return 0; | |
120 | ||
121 | /* If the addr range is not set up at symbol reading time, set it up now. | |
122 | This is for FRAME_CHAIN_VALID_ALTERNATE. I do this for coff, because | |
123 | it is unable to set it up and symbol reading time. */ | |
124 | ||
c5aa993b JM |
125 | if (symfile_objfile->ei.main_func_lowpc == INVALID_ENTRY_LOWPC && |
126 | symfile_objfile->ei.main_func_highpc == INVALID_ENTRY_HIGHPC) | |
c906108c SS |
127 | { |
128 | struct symbol *mainsym; | |
129 | ||
130 | mainsym = lookup_symbol ("main", NULL, VAR_NAMESPACE, NULL, NULL); | |
c5aa993b JM |
131 | if (mainsym && SYMBOL_CLASS (mainsym) == LOC_BLOCK) |
132 | { | |
133 | symfile_objfile->ei.main_func_lowpc = | |
c906108c | 134 | BLOCK_START (SYMBOL_BLOCK_VALUE (mainsym)); |
c5aa993b | 135 | symfile_objfile->ei.main_func_highpc = |
c906108c | 136 | BLOCK_END (SYMBOL_BLOCK_VALUE (mainsym)); |
c5aa993b | 137 | } |
c906108c | 138 | } |
c5aa993b JM |
139 | return (symfile_objfile->ei.main_func_lowpc <= pc && |
140 | symfile_objfile->ei.main_func_highpc > pc); | |
c906108c SS |
141 | } |
142 | ||
143 | /* Test a specified PC value to see if it is in the range of addresses | |
144 | that correspond to the process entry point function. See comments | |
145 | in objfiles.h for why we might want to do this. | |
146 | ||
147 | Typically called from FRAME_CHAIN_VALID. | |
148 | ||
149 | A PC of zero is always considered to be the bottom of the stack. */ | |
150 | ||
151 | int | |
152 | inside_entry_func (pc) | |
7a292a7a | 153 | CORE_ADDR pc; |
c906108c SS |
154 | { |
155 | if (pc == 0) | |
156 | return 1; | |
157 | if (symfile_objfile == 0) | |
158 | return 0; | |
7a292a7a SS |
159 | if (CALL_DUMMY_LOCATION == AT_ENTRY_POINT) |
160 | { | |
161 | /* Do not stop backtracing if the pc is in the call dummy | |
c5aa993b | 162 | at the entry point. */ |
7a292a7a SS |
163 | /* FIXME: Won't always work with zeros for the last two arguments */ |
164 | if (PC_IN_CALL_DUMMY (pc, 0, 0)) | |
165 | return 0; | |
166 | } | |
c5aa993b JM |
167 | return (symfile_objfile->ei.entry_func_lowpc <= pc && |
168 | symfile_objfile->ei.entry_func_highpc > pc); | |
c906108c SS |
169 | } |
170 | ||
171 | /* Info about the innermost stack frame (contents of FP register) */ | |
172 | ||
173 | static struct frame_info *current_frame; | |
174 | ||
175 | /* Cache for frame addresses already read by gdb. Valid only while | |
176 | inferior is stopped. Control variables for the frame cache should | |
177 | be local to this module. */ | |
178 | ||
179 | static struct obstack frame_cache_obstack; | |
180 | ||
181 | void * | |
182 | frame_obstack_alloc (size) | |
183 | unsigned long size; | |
184 | { | |
185 | return obstack_alloc (&frame_cache_obstack, size); | |
186 | } | |
187 | ||
188 | void | |
189 | frame_saved_regs_zalloc (fi) | |
190 | struct frame_info *fi; | |
191 | { | |
c5aa993b | 192 | fi->saved_regs = (CORE_ADDR *) |
c906108c SS |
193 | frame_obstack_alloc (SIZEOF_FRAME_SAVED_REGS); |
194 | memset (fi->saved_regs, 0, SIZEOF_FRAME_SAVED_REGS); | |
195 | } | |
196 | ||
197 | ||
198 | /* Return the innermost (currently executing) stack frame. */ | |
199 | ||
200 | struct frame_info * | |
201 | get_current_frame () | |
202 | { | |
203 | if (current_frame == NULL) | |
204 | { | |
205 | if (target_has_stack) | |
206 | current_frame = create_new_frame (read_fp (), read_pc ()); | |
207 | else | |
208 | error ("No stack."); | |
209 | } | |
210 | return current_frame; | |
211 | } | |
212 | ||
213 | void | |
214 | set_current_frame (frame) | |
215 | struct frame_info *frame; | |
216 | { | |
217 | current_frame = frame; | |
218 | } | |
219 | ||
220 | /* Create an arbitrary (i.e. address specified by user) or innermost frame. | |
221 | Always returns a non-NULL value. */ | |
222 | ||
223 | struct frame_info * | |
224 | create_new_frame (addr, pc) | |
225 | CORE_ADDR addr; | |
226 | CORE_ADDR pc; | |
227 | { | |
228 | struct frame_info *fi; | |
229 | char *name; | |
230 | ||
231 | fi = (struct frame_info *) | |
232 | obstack_alloc (&frame_cache_obstack, | |
233 | sizeof (struct frame_info)); | |
234 | ||
235 | /* Arbitrary frame */ | |
236 | fi->saved_regs = NULL; | |
237 | fi->next = NULL; | |
238 | fi->prev = NULL; | |
239 | fi->frame = addr; | |
240 | fi->pc = pc; | |
c5aa993b | 241 | find_pc_partial_function (pc, &name, (CORE_ADDR *) NULL, (CORE_ADDR *) NULL); |
c906108c SS |
242 | fi->signal_handler_caller = IN_SIGTRAMP (fi->pc, name); |
243 | ||
244 | #ifdef INIT_EXTRA_FRAME_INFO | |
245 | INIT_EXTRA_FRAME_INFO (0, fi); | |
246 | #endif | |
247 | ||
248 | return fi; | |
249 | } | |
250 | ||
c906108c SS |
251 | /* Return the frame that FRAME calls (NULL if FRAME is the innermost |
252 | frame). */ | |
253 | ||
254 | struct frame_info * | |
255 | get_next_frame (frame) | |
256 | struct frame_info *frame; | |
257 | { | |
258 | return frame->next; | |
259 | } | |
260 | ||
261 | /* Flush the entire frame cache. */ | |
262 | ||
263 | void | |
264 | flush_cached_frames () | |
265 | { | |
266 | /* Since we can't really be sure what the first object allocated was */ | |
267 | obstack_free (&frame_cache_obstack, 0); | |
268 | obstack_init (&frame_cache_obstack); | |
269 | ||
c5aa993b | 270 | current_frame = NULL; /* Invalidate cache */ |
c906108c SS |
271 | select_frame (NULL, -1); |
272 | annotate_frames_invalid (); | |
273 | } | |
274 | ||
275 | /* Flush the frame cache, and start a new one if necessary. */ | |
276 | ||
277 | void | |
278 | reinit_frame_cache () | |
279 | { | |
280 | flush_cached_frames (); | |
281 | ||
282 | /* FIXME: The inferior_pid test is wrong if there is a corefile. */ | |
283 | if (inferior_pid != 0) | |
284 | { | |
285 | select_frame (get_current_frame (), 0); | |
286 | } | |
287 | } | |
288 | ||
289 | /* If a machine allows frameless functions, it should define a macro | |
290 | FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) in param.h. FI is the struct | |
291 | frame_info for the frame, and FRAMELESS should be set to nonzero | |
292 | if it represents a frameless function invocation. */ | |
293 | ||
294 | /* Return nonzero if the function for this frame lacks a prologue. Many | |
295 | machines can define FRAMELESS_FUNCTION_INVOCATION to just call this | |
296 | function. */ | |
297 | ||
298 | int | |
299 | frameless_look_for_prologue (frame) | |
300 | struct frame_info *frame; | |
301 | { | |
302 | CORE_ADDR func_start, after_prologue; | |
303 | func_start = get_pc_function_start (frame->pc); | |
304 | if (func_start) | |
305 | { | |
306 | func_start += FUNCTION_START_OFFSET; | |
307 | after_prologue = func_start; | |
308 | #ifdef SKIP_PROLOGUE_FRAMELESS_P | |
309 | /* This is faster, since only care whether there *is* a prologue, | |
c5aa993b | 310 | not how long it is. */ |
b83266a0 | 311 | after_prologue = SKIP_PROLOGUE_FRAMELESS_P (after_prologue); |
c906108c | 312 | #else |
b83266a0 | 313 | after_prologue = SKIP_PROLOGUE (after_prologue); |
c906108c SS |
314 | #endif |
315 | return after_prologue == func_start; | |
316 | } | |
317 | else if (frame->pc == 0) | |
318 | /* A frame with a zero PC is usually created by dereferencing a NULL | |
319 | function pointer, normally causing an immediate core dump of the | |
320 | inferior. Mark function as frameless, as the inferior has no chance | |
321 | of setting up a stack frame. */ | |
322 | return 1; | |
323 | else | |
324 | /* If we can't find the start of the function, we don't really | |
325 | know whether the function is frameless, but we should be able | |
326 | to get a reasonable (i.e. best we can do under the | |
327 | circumstances) backtrace by saying that it isn't. */ | |
328 | return 0; | |
329 | } | |
330 | ||
331 | /* Default a few macros that people seldom redefine. */ | |
332 | ||
333 | #if !defined (INIT_FRAME_PC) | |
334 | #define INIT_FRAME_PC(fromleaf, prev) \ | |
335 | prev->pc = (fromleaf ? SAVED_PC_AFTER_CALL (prev->next) : \ | |
336 | prev->next ? FRAME_SAVED_PC (prev->next) : read_pc ()); | |
337 | #endif | |
338 | ||
339 | #ifndef FRAME_CHAIN_COMBINE | |
340 | #define FRAME_CHAIN_COMBINE(chain, thisframe) (chain) | |
341 | #endif | |
342 | ||
343 | /* Return a structure containing various interesting information | |
344 | about the frame that called NEXT_FRAME. Returns NULL | |
345 | if there is no such frame. */ | |
346 | ||
347 | struct frame_info * | |
7a292a7a | 348 | get_prev_frame (next_frame) |
c906108c SS |
349 | struct frame_info *next_frame; |
350 | { | |
351 | CORE_ADDR address = 0; | |
352 | struct frame_info *prev; | |
353 | int fromleaf = 0; | |
354 | char *name; | |
355 | ||
356 | /* If the requested entry is in the cache, return it. | |
357 | Otherwise, figure out what the address should be for the entry | |
358 | we're about to add to the cache. */ | |
359 | ||
360 | if (!next_frame) | |
361 | { | |
362 | #if 0 | |
363 | /* This screws value_of_variable, which just wants a nice clean | |
c5aa993b JM |
364 | NULL return from block_innermost_frame if there are no frames. |
365 | I don't think I've ever seen this message happen otherwise. | |
366 | And returning NULL here is a perfectly legitimate thing to do. */ | |
c906108c SS |
367 | if (!current_frame) |
368 | { | |
369 | error ("You haven't set up a process's stack to examine."); | |
370 | } | |
371 | #endif | |
372 | ||
373 | return current_frame; | |
374 | } | |
375 | ||
376 | /* If we have the prev one, return it */ | |
377 | if (next_frame->prev) | |
378 | return next_frame->prev; | |
379 | ||
380 | /* On some machines it is possible to call a function without | |
381 | setting up a stack frame for it. On these machines, we | |
382 | define this macro to take two args; a frameinfo pointer | |
383 | identifying a frame and a variable to set or clear if it is | |
384 | or isn't leafless. */ | |
392a587b | 385 | |
c906108c SS |
386 | /* Still don't want to worry about this except on the innermost |
387 | frame. This macro will set FROMLEAF if NEXT_FRAME is a | |
388 | frameless function invocation. */ | |
389 | if (!(next_frame->next)) | |
390 | { | |
392a587b | 391 | fromleaf = FRAMELESS_FUNCTION_INVOCATION (next_frame); |
c906108c SS |
392 | if (fromleaf) |
393 | address = FRAME_FP (next_frame); | |
394 | } | |
c906108c SS |
395 | |
396 | if (!fromleaf) | |
397 | { | |
398 | /* Two macros defined in tm.h specify the machine-dependent | |
c5aa993b JM |
399 | actions to be performed here. |
400 | First, get the frame's chain-pointer. | |
401 | If that is zero, the frame is the outermost frame or a leaf | |
402 | called by the outermost frame. This means that if start | |
403 | calls main without a frame, we'll return 0 (which is fine | |
404 | anyway). | |
405 | ||
406 | Nope; there's a problem. This also returns when the current | |
407 | routine is a leaf of main. This is unacceptable. We move | |
408 | this to after the ffi test; I'd rather have backtraces from | |
409 | start go curfluy than have an abort called from main not show | |
410 | main. */ | |
c906108c SS |
411 | address = FRAME_CHAIN (next_frame); |
412 | if (!FRAME_CHAIN_VALID (address, next_frame)) | |
413 | return 0; | |
414 | address = FRAME_CHAIN_COMBINE (address, next_frame); | |
415 | } | |
416 | if (address == 0) | |
417 | return 0; | |
418 | ||
419 | prev = (struct frame_info *) | |
420 | obstack_alloc (&frame_cache_obstack, | |
421 | sizeof (struct frame_info)); | |
422 | ||
423 | prev->saved_regs = NULL; | |
424 | if (next_frame) | |
425 | next_frame->prev = prev; | |
426 | prev->next = next_frame; | |
427 | prev->prev = (struct frame_info *) 0; | |
428 | prev->frame = address; | |
429 | prev->signal_handler_caller = 0; | |
430 | ||
431 | /* This change should not be needed, FIXME! We should | |
432 | determine whether any targets *need* INIT_FRAME_PC to happen | |
433 | after INIT_EXTRA_FRAME_INFO and come up with a simple way to | |
434 | express what goes on here. | |
435 | ||
c5aa993b JM |
436 | INIT_EXTRA_FRAME_INFO is called from two places: create_new_frame |
437 | (where the PC is already set up) and here (where it isn't). | |
438 | INIT_FRAME_PC is only called from here, always after | |
439 | INIT_EXTRA_FRAME_INFO. | |
440 | ||
c906108c SS |
441 | The catch is the MIPS, where INIT_EXTRA_FRAME_INFO requires the PC |
442 | value (which hasn't been set yet). Some other machines appear to | |
443 | require INIT_EXTRA_FRAME_INFO before they can do INIT_FRAME_PC. Phoo. | |
444 | ||
445 | We shouldn't need INIT_FRAME_PC_FIRST to add more complication to | |
446 | an already overcomplicated part of GDB. gnu@cygnus.com, 15Sep92. | |
447 | ||
448 | Assuming that some machines need INIT_FRAME_PC after | |
449 | INIT_EXTRA_FRAME_INFO, one possible scheme: | |
450 | ||
451 | SETUP_INNERMOST_FRAME() | |
c5aa993b JM |
452 | Default version is just create_new_frame (read_fp ()), |
453 | read_pc ()). Machines with extra frame info would do that (or the | |
454 | local equivalent) and then set the extra fields. | |
c906108c | 455 | SETUP_ARBITRARY_FRAME(argc, argv) |
c5aa993b JM |
456 | Only change here is that create_new_frame would no longer init extra |
457 | frame info; SETUP_ARBITRARY_FRAME would have to do that. | |
c906108c | 458 | INIT_PREV_FRAME(fromleaf, prev) |
c5aa993b JM |
459 | Replace INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC. This should |
460 | also return a flag saying whether to keep the new frame, or | |
461 | whether to discard it, because on some machines (e.g. mips) it | |
462 | is really awkward to have FRAME_CHAIN_VALID called *before* | |
463 | INIT_EXTRA_FRAME_INFO (there is no good way to get information | |
464 | deduced in FRAME_CHAIN_VALID into the extra fields of the new frame). | |
c906108c | 465 | std_frame_pc(fromleaf, prev) |
c5aa993b JM |
466 | This is the default setting for INIT_PREV_FRAME. It just does what |
467 | the default INIT_FRAME_PC does. Some machines will call it from | |
468 | INIT_PREV_FRAME (either at the beginning, the end, or in the middle). | |
469 | Some machines won't use it. | |
c906108c SS |
470 | kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */ |
471 | ||
472 | #ifdef INIT_FRAME_PC_FIRST | |
473 | INIT_FRAME_PC_FIRST (fromleaf, prev); | |
474 | #endif | |
475 | ||
476 | #ifdef INIT_EXTRA_FRAME_INFO | |
c5aa993b | 477 | INIT_EXTRA_FRAME_INFO (fromleaf, prev); |
c906108c SS |
478 | #endif |
479 | ||
480 | /* This entry is in the frame queue now, which is good since | |
481 | FRAME_SAVED_PC may use that queue to figure out its value | |
482 | (see tm-sparc.h). We want the pc saved in the inferior frame. */ | |
c5aa993b | 483 | INIT_FRAME_PC (fromleaf, prev); |
c906108c SS |
484 | |
485 | /* If ->frame and ->pc are unchanged, we are in the process of getting | |
486 | ourselves into an infinite backtrace. Some architectures check this | |
487 | in FRAME_CHAIN or thereabouts, but it seems like there is no reason | |
488 | this can't be an architecture-independent check. */ | |
489 | if (next_frame != NULL) | |
490 | { | |
491 | if (prev->frame == next_frame->frame | |
492 | && prev->pc == next_frame->pc) | |
493 | { | |
494 | next_frame->prev = NULL; | |
495 | obstack_free (&frame_cache_obstack, prev); | |
496 | return NULL; | |
497 | } | |
498 | } | |
499 | ||
500 | find_pc_partial_function (prev->pc, &name, | |
c5aa993b | 501 | (CORE_ADDR *) NULL, (CORE_ADDR *) NULL); |
c906108c SS |
502 | if (IN_SIGTRAMP (prev->pc, name)) |
503 | prev->signal_handler_caller = 1; | |
504 | ||
505 | return prev; | |
506 | } | |
507 | ||
508 | CORE_ADDR | |
509 | get_frame_pc (frame) | |
510 | struct frame_info *frame; | |
511 | { | |
512 | return frame->pc; | |
513 | } | |
514 | ||
515 | ||
516 | #ifdef FRAME_FIND_SAVED_REGS | |
517 | /* XXX - deprecated. This is a compatibility function for targets | |
518 | that do not yet implement FRAME_INIT_SAVED_REGS. */ | |
519 | /* Find the addresses in which registers are saved in FRAME. */ | |
520 | ||
521 | void | |
522 | get_frame_saved_regs (frame, saved_regs_addr) | |
523 | struct frame_info *frame; | |
524 | struct frame_saved_regs *saved_regs_addr; | |
525 | { | |
526 | if (frame->saved_regs == NULL) | |
527 | { | |
c5aa993b | 528 | frame->saved_regs = (CORE_ADDR *) |
c906108c SS |
529 | frame_obstack_alloc (SIZEOF_FRAME_SAVED_REGS); |
530 | } | |
531 | if (saved_regs_addr == NULL) | |
532 | { | |
533 | struct frame_saved_regs saved_regs; | |
534 | FRAME_FIND_SAVED_REGS (frame, saved_regs); | |
535 | memcpy (frame->saved_regs, &saved_regs, SIZEOF_FRAME_SAVED_REGS); | |
536 | } | |
537 | else | |
538 | { | |
539 | FRAME_FIND_SAVED_REGS (frame, *saved_regs_addr); | |
540 | memcpy (frame->saved_regs, saved_regs_addr, SIZEOF_FRAME_SAVED_REGS); | |
541 | } | |
542 | } | |
543 | #endif | |
544 | ||
545 | /* Return the innermost lexical block in execution | |
546 | in a specified stack frame. The frame address is assumed valid. */ | |
547 | ||
548 | struct block * | |
549 | get_frame_block (frame) | |
550 | struct frame_info *frame; | |
551 | { | |
552 | CORE_ADDR pc; | |
553 | ||
554 | pc = frame->pc; | |
555 | if (frame->next != 0 && frame->next->signal_handler_caller == 0) | |
556 | /* We are not in the innermost frame and we were not interrupted | |
557 | by a signal. We need to subtract one to get the correct block, | |
558 | in case the call instruction was the last instruction of the block. | |
559 | If there are any machines on which the saved pc does not point to | |
560 | after the call insn, we probably want to make frame->pc point after | |
561 | the call insn anyway. */ | |
562 | --pc; | |
563 | return block_for_pc (pc); | |
564 | } | |
565 | ||
566 | struct block * | |
567 | get_current_block () | |
568 | { | |
569 | return block_for_pc (read_pc ()); | |
570 | } | |
571 | ||
572 | CORE_ADDR | |
573 | get_pc_function_start (pc) | |
574 | CORE_ADDR pc; | |
575 | { | |
576 | register struct block *bl; | |
577 | register struct symbol *symbol; | |
578 | register struct minimal_symbol *msymbol; | |
579 | CORE_ADDR fstart; | |
580 | ||
581 | if ((bl = block_for_pc (pc)) != NULL && | |
582 | (symbol = block_function (bl)) != NULL) | |
583 | { | |
584 | bl = SYMBOL_BLOCK_VALUE (symbol); | |
585 | fstart = BLOCK_START (bl); | |
586 | } | |
587 | else if ((msymbol = lookup_minimal_symbol_by_pc (pc)) != NULL) | |
588 | { | |
589 | fstart = SYMBOL_VALUE_ADDRESS (msymbol); | |
590 | } | |
591 | else | |
592 | { | |
593 | fstart = 0; | |
594 | } | |
595 | return (fstart); | |
596 | } | |
597 | ||
598 | /* Return the symbol for the function executing in frame FRAME. */ | |
599 | ||
600 | struct symbol * | |
601 | get_frame_function (frame) | |
602 | struct frame_info *frame; | |
603 | { | |
604 | register struct block *bl = get_frame_block (frame); | |
605 | if (bl == 0) | |
606 | return 0; | |
607 | return block_function (bl); | |
608 | } | |
609 | \f | |
610 | ||
611 | /* Return the blockvector immediately containing the innermost lexical block | |
612 | containing the specified pc value and section, or 0 if there is none. | |
613 | PINDEX is a pointer to the index value of the block. If PINDEX | |
614 | is NULL, we don't pass this information back to the caller. */ | |
615 | ||
616 | struct blockvector * | |
617 | blockvector_for_pc_sect (pc, section, pindex, symtab) | |
618 | register CORE_ADDR pc; | |
619 | struct sec *section; | |
620 | int *pindex; | |
621 | struct symtab *symtab; | |
c5aa993b | 622 | |
c906108c SS |
623 | { |
624 | register struct block *b; | |
625 | register int bot, top, half; | |
626 | struct blockvector *bl; | |
627 | ||
c5aa993b | 628 | if (symtab == 0) /* if no symtab specified by caller */ |
c906108c SS |
629 | { |
630 | /* First search all symtabs for one whose file contains our pc */ | |
631 | if ((symtab = find_pc_sect_symtab (pc, section)) == 0) | |
632 | return 0; | |
633 | } | |
634 | ||
635 | bl = BLOCKVECTOR (symtab); | |
636 | b = BLOCKVECTOR_BLOCK (bl, 0); | |
637 | ||
638 | /* Then search that symtab for the smallest block that wins. */ | |
639 | /* Use binary search to find the last block that starts before PC. */ | |
640 | ||
641 | bot = 0; | |
642 | top = BLOCKVECTOR_NBLOCKS (bl); | |
643 | ||
644 | while (top - bot > 1) | |
645 | { | |
646 | half = (top - bot + 1) >> 1; | |
647 | b = BLOCKVECTOR_BLOCK (bl, bot + half); | |
648 | if (BLOCK_START (b) <= pc) | |
649 | bot += half; | |
650 | else | |
651 | top = bot + half; | |
652 | } | |
653 | ||
654 | /* Now search backward for a block that ends after PC. */ | |
655 | ||
656 | while (bot >= 0) | |
657 | { | |
658 | b = BLOCKVECTOR_BLOCK (bl, bot); | |
659 | if (BLOCK_END (b) >= pc) | |
660 | { | |
661 | if (pindex) | |
662 | *pindex = bot; | |
663 | return bl; | |
664 | } | |
665 | bot--; | |
666 | } | |
667 | return 0; | |
668 | } | |
669 | ||
670 | /* Return the blockvector immediately containing the innermost lexical block | |
671 | containing the specified pc value, or 0 if there is none. | |
672 | Backward compatibility, no section. */ | |
673 | ||
674 | struct blockvector * | |
675 | blockvector_for_pc (pc, pindex) | |
676 | register CORE_ADDR pc; | |
677 | int *pindex; | |
678 | { | |
679 | return blockvector_for_pc_sect (pc, find_pc_mapped_section (pc), | |
680 | pindex, NULL); | |
681 | } | |
682 | ||
683 | /* Return the innermost lexical block containing the specified pc value | |
684 | in the specified section, or 0 if there is none. */ | |
685 | ||
686 | struct block * | |
687 | block_for_pc_sect (pc, section) | |
688 | register CORE_ADDR pc; | |
689 | struct sec *section; | |
690 | { | |
691 | register struct blockvector *bl; | |
692 | int index; | |
693 | ||
694 | bl = blockvector_for_pc_sect (pc, section, &index, NULL); | |
695 | if (bl) | |
696 | return BLOCKVECTOR_BLOCK (bl, index); | |
697 | return 0; | |
698 | } | |
699 | ||
700 | /* Return the innermost lexical block containing the specified pc value, | |
701 | or 0 if there is none. Backward compatibility, no section. */ | |
702 | ||
703 | struct block * | |
704 | block_for_pc (pc) | |
705 | register CORE_ADDR pc; | |
706 | { | |
707 | return block_for_pc_sect (pc, find_pc_mapped_section (pc)); | |
708 | } | |
709 | ||
710 | /* Return the function containing pc value PC in section SECTION. | |
711 | Returns 0 if function is not known. */ | |
712 | ||
713 | struct symbol * | |
714 | find_pc_sect_function (pc, section) | |
715 | CORE_ADDR pc; | |
716 | struct sec *section; | |
717 | { | |
718 | register struct block *b = block_for_pc_sect (pc, section); | |
719 | if (b == 0) | |
720 | return 0; | |
721 | return block_function (b); | |
722 | } | |
723 | ||
724 | /* Return the function containing pc value PC. | |
725 | Returns 0 if function is not known. Backward compatibility, no section */ | |
726 | ||
727 | struct symbol * | |
728 | find_pc_function (pc) | |
729 | CORE_ADDR pc; | |
730 | { | |
731 | return find_pc_sect_function (pc, find_pc_mapped_section (pc)); | |
732 | } | |
733 | ||
734 | /* These variables are used to cache the most recent result | |
735 | * of find_pc_partial_function. */ | |
736 | ||
c5aa993b JM |
737 | static CORE_ADDR cache_pc_function_low = 0; |
738 | static CORE_ADDR cache_pc_function_high = 0; | |
739 | static char *cache_pc_function_name = 0; | |
c906108c SS |
740 | static struct sec *cache_pc_function_section = NULL; |
741 | ||
742 | /* Clear cache, e.g. when symbol table is discarded. */ | |
743 | ||
744 | void | |
c5aa993b | 745 | clear_pc_function_cache () |
c906108c SS |
746 | { |
747 | cache_pc_function_low = 0; | |
748 | cache_pc_function_high = 0; | |
c5aa993b | 749 | cache_pc_function_name = (char *) 0; |
c906108c SS |
750 | cache_pc_function_section = NULL; |
751 | } | |
752 | ||
753 | /* Finds the "function" (text symbol) that is smaller than PC but | |
754 | greatest of all of the potential text symbols in SECTION. Sets | |
755 | *NAME and/or *ADDRESS conditionally if that pointer is non-null. | |
756 | If ENDADDR is non-null, then set *ENDADDR to be the end of the | |
757 | function (exclusive), but passing ENDADDR as non-null means that | |
758 | the function might cause symbols to be read. This function either | |
759 | succeeds or fails (not halfway succeeds). If it succeeds, it sets | |
760 | *NAME, *ADDRESS, and *ENDADDR to real information and returns 1. | |
761 | If it fails, it sets *NAME, *ADDRESS, and *ENDADDR to zero and | |
762 | returns 0. */ | |
763 | ||
764 | int | |
765 | find_pc_sect_partial_function (pc, section, name, address, endaddr) | |
c5aa993b JM |
766 | CORE_ADDR pc; |
767 | asection *section; | |
768 | char **name; | |
c906108c SS |
769 | CORE_ADDR *address; |
770 | CORE_ADDR *endaddr; | |
771 | { | |
772 | struct partial_symtab *pst; | |
c5aa993b | 773 | struct symbol *f; |
c906108c SS |
774 | struct minimal_symbol *msymbol; |
775 | struct partial_symbol *psb; | |
c5aa993b | 776 | struct obj_section *osect; |
c906108c SS |
777 | int i; |
778 | CORE_ADDR mapped_pc; | |
779 | ||
780 | mapped_pc = overlay_mapped_address (pc, section); | |
781 | ||
c5aa993b | 782 | if (mapped_pc >= cache_pc_function_low && |
c906108c SS |
783 | mapped_pc < cache_pc_function_high && |
784 | section == cache_pc_function_section) | |
785 | goto return_cached_value; | |
786 | ||
787 | /* If sigtramp is in the u area, it counts as a function (especially | |
788 | important for step_1). */ | |
789 | #if defined SIGTRAMP_START | |
c5aa993b | 790 | if (IN_SIGTRAMP (mapped_pc, (char *) NULL)) |
c906108c | 791 | { |
c5aa993b JM |
792 | cache_pc_function_low = SIGTRAMP_START (mapped_pc); |
793 | cache_pc_function_high = SIGTRAMP_END (mapped_pc); | |
794 | cache_pc_function_name = "<sigtramp>"; | |
c906108c SS |
795 | cache_pc_function_section = section; |
796 | goto return_cached_value; | |
797 | } | |
798 | #endif | |
799 | ||
800 | msymbol = lookup_minimal_symbol_by_pc_section (mapped_pc, section); | |
801 | pst = find_pc_sect_psymtab (mapped_pc, section); | |
802 | if (pst) | |
803 | { | |
804 | /* Need to read the symbols to get a good value for the end address. */ | |
805 | if (endaddr != NULL && !pst->readin) | |
806 | { | |
807 | /* Need to get the terminal in case symbol-reading produces | |
808 | output. */ | |
809 | target_terminal_ours_for_output (); | |
810 | PSYMTAB_TO_SYMTAB (pst); | |
811 | } | |
812 | ||
813 | if (pst->readin) | |
814 | { | |
815 | /* Checking whether the msymbol has a larger value is for the | |
816 | "pathological" case mentioned in print_frame_info. */ | |
817 | f = find_pc_sect_function (mapped_pc, section); | |
818 | if (f != NULL | |
819 | && (msymbol == NULL | |
820 | || (BLOCK_START (SYMBOL_BLOCK_VALUE (f)) | |
821 | >= SYMBOL_VALUE_ADDRESS (msymbol)))) | |
822 | { | |
c5aa993b JM |
823 | cache_pc_function_low = BLOCK_START (SYMBOL_BLOCK_VALUE (f)); |
824 | cache_pc_function_high = BLOCK_END (SYMBOL_BLOCK_VALUE (f)); | |
825 | cache_pc_function_name = SYMBOL_NAME (f); | |
c906108c SS |
826 | cache_pc_function_section = section; |
827 | goto return_cached_value; | |
828 | } | |
829 | } | |
830 | else | |
831 | { | |
832 | /* Now that static symbols go in the minimal symbol table, perhaps | |
833 | we could just ignore the partial symbols. But at least for now | |
834 | we use the partial or minimal symbol, whichever is larger. */ | |
835 | psb = find_pc_sect_psymbol (pst, mapped_pc, section); | |
836 | ||
837 | if (psb | |
838 | && (msymbol == NULL || | |
839 | (SYMBOL_VALUE_ADDRESS (psb) | |
840 | >= SYMBOL_VALUE_ADDRESS (msymbol)))) | |
841 | { | |
842 | /* This case isn't being cached currently. */ | |
843 | if (address) | |
844 | *address = SYMBOL_VALUE_ADDRESS (psb); | |
845 | if (name) | |
846 | *name = SYMBOL_NAME (psb); | |
847 | /* endaddr non-NULL can't happen here. */ | |
848 | return 1; | |
849 | } | |
850 | } | |
851 | } | |
852 | ||
853 | /* Not in the normal symbol tables, see if the pc is in a known section. | |
854 | If it's not, then give up. This ensures that anything beyond the end | |
855 | of the text seg doesn't appear to be part of the last function in the | |
856 | text segment. */ | |
857 | ||
858 | osect = find_pc_sect_section (mapped_pc, section); | |
859 | ||
860 | if (!osect) | |
861 | msymbol = NULL; | |
862 | ||
863 | /* Must be in the minimal symbol table. */ | |
864 | if (msymbol == NULL) | |
865 | { | |
866 | /* No available symbol. */ | |
867 | if (name != NULL) | |
868 | *name = 0; | |
869 | if (address != NULL) | |
870 | *address = 0; | |
871 | if (endaddr != NULL) | |
872 | *endaddr = 0; | |
873 | return 0; | |
874 | } | |
875 | ||
c5aa993b JM |
876 | cache_pc_function_low = SYMBOL_VALUE_ADDRESS (msymbol); |
877 | cache_pc_function_name = SYMBOL_NAME (msymbol); | |
c906108c SS |
878 | cache_pc_function_section = section; |
879 | ||
880 | /* Use the lesser of the next minimal symbol in the same section, or | |
881 | the end of the section, as the end of the function. */ | |
c5aa993b | 882 | |
c906108c SS |
883 | /* Step over other symbols at this same address, and symbols in |
884 | other sections, to find the next symbol in this section with | |
885 | a different address. */ | |
886 | ||
c5aa993b | 887 | for (i = 1; SYMBOL_NAME (msymbol + i) != NULL; i++) |
c906108c | 888 | { |
c5aa993b JM |
889 | if (SYMBOL_VALUE_ADDRESS (msymbol + i) != SYMBOL_VALUE_ADDRESS (msymbol) |
890 | && SYMBOL_BFD_SECTION (msymbol + i) == SYMBOL_BFD_SECTION (msymbol)) | |
c906108c SS |
891 | break; |
892 | } | |
893 | ||
894 | if (SYMBOL_NAME (msymbol + i) != NULL | |
895 | && SYMBOL_VALUE_ADDRESS (msymbol + i) < osect->endaddr) | |
896 | cache_pc_function_high = SYMBOL_VALUE_ADDRESS (msymbol + i); | |
897 | else | |
898 | /* We got the start address from the last msymbol in the objfile. | |
899 | So the end address is the end of the section. */ | |
900 | cache_pc_function_high = osect->endaddr; | |
901 | ||
c5aa993b | 902 | return_cached_value: |
c906108c SS |
903 | |
904 | if (address) | |
905 | { | |
906 | if (pc_in_unmapped_range (pc, section)) | |
c5aa993b | 907 | *address = overlay_unmapped_address (cache_pc_function_low, section); |
c906108c | 908 | else |
c5aa993b | 909 | *address = cache_pc_function_low; |
c906108c | 910 | } |
c5aa993b | 911 | |
c906108c SS |
912 | if (name) |
913 | *name = cache_pc_function_name; | |
914 | ||
915 | if (endaddr) | |
916 | { | |
917 | if (pc_in_unmapped_range (pc, section)) | |
c5aa993b | 918 | { |
c906108c SS |
919 | /* Because the high address is actually beyond the end of |
920 | the function (and therefore possibly beyond the end of | |
921 | the overlay), we must actually convert (high - 1) | |
922 | and then add one to that. */ | |
923 | ||
c5aa993b | 924 | *endaddr = 1 + overlay_unmapped_address (cache_pc_function_high - 1, |
c906108c | 925 | section); |
c5aa993b | 926 | } |
c906108c | 927 | else |
c5aa993b | 928 | *endaddr = cache_pc_function_high; |
c906108c SS |
929 | } |
930 | ||
931 | return 1; | |
932 | } | |
933 | ||
934 | /* Backward compatibility, no section argument */ | |
935 | ||
936 | int | |
937 | find_pc_partial_function (pc, name, address, endaddr) | |
c5aa993b JM |
938 | CORE_ADDR pc; |
939 | char **name; | |
c906108c SS |
940 | CORE_ADDR *address; |
941 | CORE_ADDR *endaddr; | |
942 | { | |
c5aa993b | 943 | asection *section; |
c906108c SS |
944 | |
945 | section = find_pc_overlay (pc); | |
946 | return find_pc_sect_partial_function (pc, section, name, address, endaddr); | |
947 | } | |
948 | ||
949 | /* Return the innermost stack frame executing inside of BLOCK, | |
950 | or NULL if there is no such frame. If BLOCK is NULL, just return NULL. */ | |
951 | ||
952 | struct frame_info * | |
953 | block_innermost_frame (block) | |
954 | struct block *block; | |
955 | { | |
956 | struct frame_info *frame; | |
957 | register CORE_ADDR start; | |
958 | register CORE_ADDR end; | |
959 | ||
960 | if (block == NULL) | |
961 | return NULL; | |
962 | ||
963 | start = BLOCK_START (block); | |
964 | end = BLOCK_END (block); | |
965 | ||
966 | frame = NULL; | |
967 | while (1) | |
968 | { | |
969 | frame = get_prev_frame (frame); | |
970 | if (frame == NULL) | |
971 | return NULL; | |
972 | if (frame->pc >= start && frame->pc < end) | |
973 | return frame; | |
974 | } | |
975 | } | |
976 | ||
977 | /* Return the full FRAME which corresponds to the given CORE_ADDR | |
978 | or NULL if no FRAME on the chain corresponds to CORE_ADDR. */ | |
979 | ||
980 | struct frame_info * | |
981 | find_frame_addr_in_frame_chain (frame_addr) | |
982 | CORE_ADDR frame_addr; | |
983 | { | |
984 | struct frame_info *frame = NULL; | |
985 | ||
c5aa993b | 986 | if (frame_addr == (CORE_ADDR) 0) |
c906108c SS |
987 | return NULL; |
988 | ||
989 | while (1) | |
990 | { | |
991 | frame = get_prev_frame (frame); | |
992 | if (frame == NULL) | |
993 | return NULL; | |
994 | if (FRAME_FP (frame) == frame_addr) | |
995 | return frame; | |
996 | } | |
997 | } | |
998 | ||
999 | #ifdef SIGCONTEXT_PC_OFFSET | |
1000 | /* Get saved user PC for sigtramp from sigcontext for BSD style sigtramp. */ | |
1001 | ||
1002 | CORE_ADDR | |
1003 | sigtramp_saved_pc (frame) | |
1004 | struct frame_info *frame; | |
1005 | { | |
1006 | CORE_ADDR sigcontext_addr; | |
1007 | char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT]; | |
1008 | int ptrbytes = TARGET_PTR_BIT / TARGET_CHAR_BIT; | |
1009 | int sigcontext_offs = (2 * TARGET_INT_BIT) / TARGET_CHAR_BIT; | |
1010 | ||
1011 | /* Get sigcontext address, it is the third parameter on the stack. */ | |
1012 | if (frame->next) | |
1013 | sigcontext_addr = read_memory_integer (FRAME_ARGS_ADDRESS (frame->next) | |
1014 | + FRAME_ARGS_SKIP | |
1015 | + sigcontext_offs, | |
1016 | ptrbytes); | |
1017 | else | |
1018 | sigcontext_addr = read_memory_integer (read_register (SP_REGNUM) | |
c5aa993b | 1019 | + sigcontext_offs, |
c906108c SS |
1020 | ptrbytes); |
1021 | ||
1022 | /* Don't cause a memory_error when accessing sigcontext in case the stack | |
1023 | layout has changed or the stack is corrupt. */ | |
1024 | target_read_memory (sigcontext_addr + SIGCONTEXT_PC_OFFSET, buf, ptrbytes); | |
1025 | return extract_unsigned_integer (buf, ptrbytes); | |
1026 | } | |
1027 | #endif /* SIGCONTEXT_PC_OFFSET */ | |
1028 | ||
7a292a7a SS |
1029 | |
1030 | /* Are we in a call dummy? The code below which allows DECR_PC_AFTER_BREAK | |
1031 | below is for infrun.c, which may give the macro a pc without that | |
1032 | subtracted out. */ | |
1033 | ||
1034 | extern CORE_ADDR text_end; | |
1035 | ||
1036 | int | |
1037 | pc_in_call_dummy_before_text_end (pc, sp, frame_address) | |
1038 | CORE_ADDR pc; | |
1039 | CORE_ADDR sp; | |
1040 | CORE_ADDR frame_address; | |
1041 | { | |
1042 | return ((pc) >= text_end - CALL_DUMMY_LENGTH | |
1043 | && (pc) <= text_end + DECR_PC_AFTER_BREAK); | |
1044 | } | |
1045 | ||
1046 | int | |
1047 | pc_in_call_dummy_after_text_end (pc, sp, frame_address) | |
1048 | CORE_ADDR pc; | |
1049 | CORE_ADDR sp; | |
1050 | CORE_ADDR frame_address; | |
1051 | { | |
1052 | return ((pc) >= text_end | |
1053 | && (pc) <= text_end + CALL_DUMMY_LENGTH + DECR_PC_AFTER_BREAK); | |
1054 | } | |
1055 | ||
1056 | /* Is the PC in a call dummy? SP and FRAME_ADDRESS are the bottom and | |
1057 | top of the stack frame which we are checking, where "bottom" and | |
1058 | "top" refer to some section of memory which contains the code for | |
1059 | the call dummy. Calls to this macro assume that the contents of | |
1060 | SP_REGNUM and FP_REGNUM (or the saved values thereof), respectively, | |
1061 | are the things to pass. | |
1062 | ||
1063 | This won't work on the 29k, where SP_REGNUM and FP_REGNUM don't | |
1064 | have that meaning, but the 29k doesn't use ON_STACK. This could be | |
1065 | fixed by generalizing this scheme, perhaps by passing in a frame | |
1066 | and adding a few fields, at least on machines which need them for | |
1067 | PC_IN_CALL_DUMMY. | |
1068 | ||
1069 | Something simpler, like checking for the stack segment, doesn't work, | |
1070 | since various programs (threads implementations, gcc nested function | |
1071 | stubs, etc) may either allocate stack frames in another segment, or | |
1072 | allocate other kinds of code on the stack. */ | |
1073 | ||
1074 | int | |
1075 | pc_in_call_dummy_on_stack (pc, sp, frame_address) | |
1076 | CORE_ADDR pc; | |
1077 | CORE_ADDR sp; | |
1078 | CORE_ADDR frame_address; | |
1079 | { | |
1080 | return (INNER_THAN ((sp), (pc)) | |
1081 | && (frame_address != 0) | |
1082 | && INNER_THAN ((pc), (frame_address))); | |
1083 | } | |
1084 | ||
1085 | int | |
1086 | pc_in_call_dummy_at_entry_point (pc, sp, frame_address) | |
1087 | CORE_ADDR pc; | |
1088 | CORE_ADDR sp; | |
1089 | CORE_ADDR frame_address; | |
1090 | { | |
1091 | return ((pc) >= CALL_DUMMY_ADDRESS () | |
1092 | && (pc) <= (CALL_DUMMY_ADDRESS () + DECR_PC_AFTER_BREAK)); | |
1093 | } | |
1094 | ||
c906108c SS |
1095 | |
1096 | /* | |
1097 | * GENERIC DUMMY FRAMES | |
1098 | * | |
1099 | * The following code serves to maintain the dummy stack frames for | |
1100 | * inferior function calls (ie. when gdb calls into the inferior via | |
1101 | * call_function_by_hand). This code saves the machine state before | |
1102 | * the call in host memory, so we must maintain an independant stack | |
1103 | * and keep it consistant etc. I am attempting to make this code | |
1104 | * generic enough to be used by many targets. | |
1105 | * | |
1106 | * The cheapest and most generic way to do CALL_DUMMY on a new target | |
1107 | * is probably to define CALL_DUMMY to be empty, CALL_DUMMY_LENGTH to | |
1108 | * zero, and CALL_DUMMY_LOCATION to AT_ENTRY. Then you must remember | |
1109 | * to define PUSH_RETURN_ADDRESS, because no call instruction will be | |
1110 | * being executed by the target. Also FRAME_CHAIN_VALID as | |
cce74817 JM |
1111 | * generic_frame_chain_valid and FIX_CALL_DUMMY as |
1112 | * generic_fix_call_dummy. */ | |
c906108c | 1113 | |
7a292a7a SS |
1114 | /* Dummy frame. This saves the processor state just prior to setting |
1115 | up the inferior function call. Older targets save the registers | |
1116 | target stack (but that really slows down function calls). */ | |
1117 | ||
1118 | struct dummy_frame | |
1119 | { | |
1120 | struct dummy_frame *next; | |
1121 | ||
1122 | CORE_ADDR pc; | |
1123 | CORE_ADDR fp; | |
1124 | CORE_ADDR sp; | |
43ff13b4 | 1125 | CORE_ADDR top; |
7a292a7a SS |
1126 | char *registers; |
1127 | }; | |
1128 | ||
c906108c SS |
1129 | static struct dummy_frame *dummy_frame_stack = NULL; |
1130 | ||
1131 | /* Function: find_dummy_frame(pc, fp, sp) | |
1132 | Search the stack of dummy frames for one matching the given PC, FP and SP. | |
1133 | This is the work-horse for pc_in_call_dummy and read_register_dummy */ | |
1134 | ||
c5aa993b | 1135 | char * |
c906108c SS |
1136 | generic_find_dummy_frame (pc, fp) |
1137 | CORE_ADDR pc; | |
1138 | CORE_ADDR fp; | |
1139 | { | |
c5aa993b | 1140 | struct dummy_frame *dummyframe; |
c906108c SS |
1141 | |
1142 | if (pc != entry_point_address ()) | |
1143 | return 0; | |
1144 | ||
1145 | for (dummyframe = dummy_frame_stack; dummyframe != NULL; | |
1146 | dummyframe = dummyframe->next) | |
43ff13b4 JM |
1147 | if (fp == dummyframe->fp |
1148 | || fp == dummyframe->sp | |
1149 | || fp == dummyframe->top) | |
c906108c | 1150 | /* The frame in question lies between the saved fp and sp, inclusive */ |
7a292a7a | 1151 | return dummyframe->registers; |
c906108c SS |
1152 | |
1153 | return 0; | |
1154 | } | |
1155 | ||
1156 | /* Function: pc_in_call_dummy (pc, fp) | |
1157 | Return true if this is a dummy frame created by gdb for an inferior call */ | |
1158 | ||
1159 | int | |
7a292a7a | 1160 | generic_pc_in_call_dummy (pc, sp, fp) |
c906108c | 1161 | CORE_ADDR pc; |
7a292a7a | 1162 | CORE_ADDR sp; |
c906108c SS |
1163 | CORE_ADDR fp; |
1164 | { | |
1165 | /* if find_dummy_frame succeeds, then PC is in a call dummy */ | |
7a292a7a SS |
1166 | /* Note: SP and not FP is passed on. */ |
1167 | return (generic_find_dummy_frame (pc, sp) != 0); | |
c906108c SS |
1168 | } |
1169 | ||
1170 | /* Function: read_register_dummy | |
1171 | Find a saved register from before GDB calls a function in the inferior */ | |
1172 | ||
1173 | CORE_ADDR | |
1174 | generic_read_register_dummy (pc, fp, regno) | |
1175 | CORE_ADDR pc; | |
1176 | CORE_ADDR fp; | |
1177 | int regno; | |
1178 | { | |
1179 | char *dummy_regs = generic_find_dummy_frame (pc, fp); | |
1180 | ||
1181 | if (dummy_regs) | |
1182 | return extract_address (&dummy_regs[REGISTER_BYTE (regno)], | |
c5aa993b | 1183 | REGISTER_RAW_SIZE (regno)); |
c906108c SS |
1184 | else |
1185 | return 0; | |
1186 | } | |
1187 | ||
1188 | /* Save all the registers on the dummy frame stack. Most ports save the | |
1189 | registers on the target stack. This results in lots of unnecessary memory | |
1190 | references, which are slow when debugging via a serial line. Instead, we | |
1191 | save all the registers internally, and never write them to the stack. The | |
1192 | registers get restored when the called function returns to the entry point, | |
1193 | where a breakpoint is laying in wait. */ | |
1194 | ||
1195 | void | |
1196 | generic_push_dummy_frame () | |
1197 | { | |
1198 | struct dummy_frame *dummy_frame; | |
1199 | CORE_ADDR fp = (get_current_frame ())->frame; | |
1200 | ||
1201 | /* check to see if there are stale dummy frames, | |
1202 | perhaps left over from when a longjump took us out of a | |
1203 | function that was called by the debugger */ | |
1204 | ||
1205 | dummy_frame = dummy_frame_stack; | |
1206 | while (dummy_frame) | |
1207 | if (INNER_THAN (dummy_frame->fp, fp)) /* stale -- destroy! */ | |
1208 | { | |
1209 | dummy_frame_stack = dummy_frame->next; | |
43ff13b4 | 1210 | free (dummy_frame->registers); |
c906108c SS |
1211 | free (dummy_frame); |
1212 | dummy_frame = dummy_frame_stack; | |
1213 | } | |
1214 | else | |
1215 | dummy_frame = dummy_frame->next; | |
1216 | ||
1217 | dummy_frame = xmalloc (sizeof (struct dummy_frame)); | |
7a292a7a SS |
1218 | dummy_frame->registers = xmalloc (REGISTER_BYTES); |
1219 | ||
c5aa993b JM |
1220 | dummy_frame->pc = read_register (PC_REGNUM); |
1221 | dummy_frame->sp = read_register (SP_REGNUM); | |
1222 | dummy_frame->top = dummy_frame->sp; | |
1223 | dummy_frame->fp = fp; | |
7a292a7a | 1224 | read_register_bytes (0, dummy_frame->registers, REGISTER_BYTES); |
c906108c SS |
1225 | dummy_frame->next = dummy_frame_stack; |
1226 | dummy_frame_stack = dummy_frame; | |
1227 | } | |
1228 | ||
43ff13b4 JM |
1229 | void |
1230 | generic_save_dummy_frame_tos (sp) | |
1231 | CORE_ADDR sp; | |
1232 | { | |
1233 | dummy_frame_stack->top = sp; | |
1234 | } | |
1235 | ||
c906108c SS |
1236 | /* Function: pop_frame |
1237 | Restore the machine state from either the saved dummy stack or a | |
1238 | real stack frame. */ | |
1239 | ||
1240 | void | |
1241 | generic_pop_current_frame (pop) | |
c5aa993b | 1242 | void (*pop) PARAMS ((struct frame_info * frame)); |
c906108c SS |
1243 | { |
1244 | struct frame_info *frame = get_current_frame (); | |
c5aa993b | 1245 | if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame)) |
c906108c SS |
1246 | generic_pop_dummy_frame (); |
1247 | else | |
1248 | pop (frame); | |
1249 | } | |
1250 | ||
1251 | /* Function: pop_dummy_frame | |
1252 | Restore the machine state from a saved dummy stack frame. */ | |
1253 | ||
1254 | void | |
1255 | generic_pop_dummy_frame () | |
1256 | { | |
1257 | struct dummy_frame *dummy_frame = dummy_frame_stack; | |
1258 | ||
1259 | /* FIXME: what if the first frame isn't the right one, eg.. | |
1260 | because one call-by-hand function has done a longjmp into another one? */ | |
1261 | ||
1262 | if (!dummy_frame) | |
1263 | error ("Can't pop dummy frame!"); | |
1264 | dummy_frame_stack = dummy_frame->next; | |
7a292a7a | 1265 | write_register_bytes (0, dummy_frame->registers, REGISTER_BYTES); |
c906108c | 1266 | flush_cached_frames (); |
7a292a7a SS |
1267 | |
1268 | free (dummy_frame->registers); | |
c906108c SS |
1269 | free (dummy_frame); |
1270 | } | |
1271 | ||
1272 | /* Function: frame_chain_valid | |
1273 | Returns true for a user frame or a call_function_by_hand dummy frame, | |
1274 | and false for the CRT0 start-up frame. Purpose is to terminate backtrace */ | |
c5aa993b | 1275 | |
c906108c SS |
1276 | int |
1277 | generic_frame_chain_valid (fp, fi) | |
1278 | CORE_ADDR fp; | |
1279 | struct frame_info *fi; | |
1280 | { | |
c5aa993b JM |
1281 | if (PC_IN_CALL_DUMMY (FRAME_SAVED_PC (fi), fp, fp)) |
1282 | return 1; /* don't prune CALL_DUMMY frames */ | |
1283 | else /* fall back to default algorithm (see frame.h) */ | |
c906108c SS |
1284 | return (fp != 0 |
1285 | && (INNER_THAN (fi->frame, fp) || fi->frame == fp) | |
c5aa993b | 1286 | && !inside_entry_file (FRAME_SAVED_PC (fi))); |
c906108c | 1287 | } |
c5aa993b | 1288 | |
cce74817 JM |
1289 | /* Function: fix_call_dummy |
1290 | Stub function. Generic dumy frames typically do not need to fix | |
1291 | the frame being created */ | |
1292 | ||
1293 | void | |
1294 | generic_fix_call_dummy (dummy, pc, fun, nargs, args, type, gcc_p) | |
1295 | char *dummy; | |
1296 | CORE_ADDR pc; | |
1297 | CORE_ADDR fun; | |
1298 | int nargs; | |
1299 | struct value **args; | |
1300 | struct type *type; | |
1301 | int gcc_p; | |
1302 | { | |
1303 | return; | |
1304 | } | |
1305 | ||
c906108c SS |
1306 | /* Function: get_saved_register |
1307 | Find register number REGNUM relative to FRAME and put its (raw, | |
1308 | target format) contents in *RAW_BUFFER. | |
1309 | ||
1310 | Set *OPTIMIZED if the variable was optimized out (and thus can't be | |
1311 | fetched). Note that this is never set to anything other than zero | |
1312 | in this implementation. | |
1313 | ||
1314 | Set *LVAL to lval_memory, lval_register, or not_lval, depending on | |
1315 | whether the value was fetched from memory, from a register, or in a | |
1316 | strange and non-modifiable way (e.g. a frame pointer which was | |
1317 | calculated rather than fetched). We will use not_lval for values | |
1318 | fetched from generic dummy frames. | |
1319 | ||
1320 | Set *ADDRP to the address, either in memory on as a REGISTER_BYTE | |
1321 | offset into the registers array. If the value is stored in a dummy | |
1322 | frame, set *ADDRP to zero. | |
1323 | ||
1324 | To use this implementation, define a function called | |
1325 | "get_saved_register" in your target code, which simply passes all | |
1326 | of its arguments to this function. | |
1327 | ||
1328 | The argument RAW_BUFFER must point to aligned memory. */ | |
1329 | ||
1330 | void | |
1331 | generic_get_saved_register (raw_buffer, optimized, addrp, frame, regnum, lval) | |
1332 | char *raw_buffer; | |
1333 | int *optimized; | |
1334 | CORE_ADDR *addrp; | |
1335 | struct frame_info *frame; | |
1336 | int regnum; | |
1337 | enum lval_type *lval; | |
1338 | { | |
1339 | if (!target_has_registers) | |
1340 | error ("No registers."); | |
1341 | ||
1342 | /* Normal systems don't optimize out things with register numbers. */ | |
1343 | if (optimized != NULL) | |
1344 | *optimized = 0; | |
1345 | ||
c5aa993b | 1346 | if (addrp) /* default assumption: not found in memory */ |
c906108c SS |
1347 | *addrp = 0; |
1348 | ||
1349 | /* Note: since the current frame's registers could only have been | |
1350 | saved by frames INTERIOR TO the current frame, we skip examining | |
1351 | the current frame itself: otherwise, we would be getting the | |
1352 | previous frame's registers which were saved by the current frame. */ | |
1353 | ||
1354 | while (frame && ((frame = frame->next) != NULL)) | |
1355 | { | |
1356 | if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame)) | |
1357 | { | |
c5aa993b | 1358 | if (lval) /* found it in a CALL_DUMMY frame */ |
c906108c SS |
1359 | *lval = not_lval; |
1360 | if (raw_buffer) | |
c5aa993b JM |
1361 | memcpy (raw_buffer, |
1362 | generic_find_dummy_frame (frame->pc, frame->frame) + | |
c906108c SS |
1363 | REGISTER_BYTE (regnum), |
1364 | REGISTER_RAW_SIZE (regnum)); | |
c5aa993b | 1365 | return; |
c906108c SS |
1366 | } |
1367 | ||
1368 | FRAME_INIT_SAVED_REGS (frame); | |
1369 | if (frame->saved_regs != NULL | |
1370 | && frame->saved_regs[regnum] != 0) | |
1371 | { | |
c5aa993b | 1372 | if (lval) /* found it saved on the stack */ |
c906108c SS |
1373 | *lval = lval_memory; |
1374 | if (regnum == SP_REGNUM) | |
1375 | { | |
c5aa993b JM |
1376 | if (raw_buffer) /* SP register treated specially */ |
1377 | store_address (raw_buffer, REGISTER_RAW_SIZE (regnum), | |
c906108c SS |
1378 | frame->saved_regs[regnum]); |
1379 | } | |
1380 | else | |
1381 | { | |
c5aa993b | 1382 | if (addrp) /* any other register */ |
c906108c SS |
1383 | *addrp = frame->saved_regs[regnum]; |
1384 | if (raw_buffer) | |
c5aa993b | 1385 | read_memory (frame->saved_regs[regnum], raw_buffer, |
c906108c SS |
1386 | REGISTER_RAW_SIZE (regnum)); |
1387 | } | |
1388 | return; | |
1389 | } | |
1390 | } | |
1391 | ||
1392 | /* If we get thru the loop to this point, it means the register was | |
1393 | not saved in any frame. Return the actual live-register value. */ | |
1394 | ||
c5aa993b | 1395 | if (lval) /* found it in a live register */ |
c906108c SS |
1396 | *lval = lval_register; |
1397 | if (addrp) | |
1398 | *addrp = REGISTER_BYTE (regnum); | |
1399 | if (raw_buffer) | |
1400 | read_register_gen (regnum, raw_buffer); | |
1401 | } | |
c906108c SS |
1402 | |
1403 | void | |
1404 | _initialize_blockframe () | |
1405 | { | |
1406 | obstack_init (&frame_cache_obstack); | |
1407 | } |