1/* Definitions for dealing with stack frames, for GDB, the GNU debugger. 2 3 Copyright (C) 1986, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1996, 1997, 4 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2007 5 Free Software Foundation, Inc. 6 7 This file is part of GDB. 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 3 of the License, or 12 (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 21 22#if !defined (FRAME_H) 23#define FRAME_H 1 24 25/* The following is the intended naming schema for frame functions. 26 It isn't 100% consistent, but it is aproaching that. Frame naming 27 schema: 28 29 Prefixes: 30 31 get_frame_WHAT...(): Get WHAT from the THIS frame (functionaly 32 equivalent to THIS->next->unwind->what) 33 34 frame_unwind_WHAT...(): Unwind THIS frame's WHAT from the NEXT 35 frame. 36 37 put_frame_WHAT...(): Put a value into this frame (unsafe, need to 38 invalidate the frame / regcache afterwards) (better name more 39 strongly hinting at its unsafeness) 40 41 safe_....(): Safer version of various functions, doesn't throw an 42 error (leave this for later?). Returns non-zero / non-NULL if the 43 request succeeds, zero / NULL otherwize. 44 45 Suffixes: 46 47 void /frame/_WHAT(): Read WHAT's value into the buffer parameter. 48 49 ULONGEST /frame/_WHAT_unsigned(): Return an unsigned value (the 50 alternative is *frame_unsigned_WHAT). 51 52 LONGEST /frame/_WHAT_signed(): Return WHAT signed value. 53 54 What: 55 56 /frame/_memory* (frame, coreaddr, len [, buf]): Extract/return 57 *memory. 58 59 /frame/_register* (frame, regnum [, buf]): extract/return register. 60 61 CORE_ADDR /frame/_{pc,sp,...} (frame): Resume address, innner most 62 stack *address, ... 63 64 */ 65 66struct symtab_and_line; 67struct frame_unwind; 68struct frame_base; 69struct block; 70struct gdbarch; 71struct ui_file; 72 73/* The frame object. */ 74 75struct frame_info; 76 77/* The frame object's ID. This provides a per-frame unique identifier 78 that can be used to relocate a `struct frame_info' after a target 79 resume or a frame cache destruct. It of course assumes that the 80 inferior hasn't unwound the stack past that frame. */ 81 82struct frame_id 83{ 84 /* The frame's stack address. This shall be constant through out 85 the lifetime of a frame. Note that this requirement applies to 86 not just the function body, but also the prologue and (in theory 87 at least) the epilogue. Since that value needs to fall either on 88 the boundary, or within the frame's address range, the frame's 89 outer-most address (the inner-most address of the previous frame) 90 is used. Watch out for all the legacy targets that still use the 91 function pointer register or stack pointer register. They are 92 wrong. 93 94 This field is valid only if stack_addr_p is true. Otherwise, this 95 frame represents the null frame. */ 96 CORE_ADDR stack_addr; 97 98 /* The frame's code address. This shall be constant through out the 99 lifetime of the frame. While the PC (a.k.a. resume address) 100 changes as the function is executed, this code address cannot. 101 Typically, it is set to the address of the entry point of the 102 frame's function (as returned by frame_func_unwind(). 103 104 This field is valid only if code_addr_p is true. Otherwise, this 105 frame is considered to have a wildcard code address, i.e. one that 106 matches every address value in frame comparisons. */ 107 CORE_ADDR code_addr; 108 109 /* The frame's special address. This shall be constant through out the 110 lifetime of the frame. This is used for architectures that may have 111 frames that do not change the stack but are still distinct and have 112 some form of distinct identifier (e.g. the ia64 which uses a 2nd 113 stack for registers). This field is treated as unordered - i.e. will 114 not be used in frame ordering comparisons such as frame_id_inner(). 115 116 This field is valid only if special_addr_p is true. Otherwise, this 117 frame is considered to have a wildcard special address, i.e. one that 118 matches every address value in frame comparisons. */ 119 CORE_ADDR special_addr; 120 121 /* Flags to indicate the above fields have valid contents. */ 122 unsigned int stack_addr_p : 1; 123 unsigned int code_addr_p : 1; 124 unsigned int special_addr_p : 1; 125}; 126 127/* Methods for constructing and comparing Frame IDs. 128 129 NOTE: Given stackless functions A and B, where A calls B (and hence 130 B is inner-to A). The relationships: !eq(A,B); !eq(B,A); 131 !inner(A,B); !inner(B,A); all hold. 132 133 This is because, while B is inner-to A, B is not strictly inner-to A. 134 Being stackless, they have an identical .stack_addr value, and differ 135 only by their unordered .code_addr and/or .special_addr values. 136 137 Because frame_id_inner is only used as a safety net (e.g., 138 detect a corrupt stack) the lack of strictness is not a problem. 139 Code needing to determine an exact relationship between two frames 140 must instead use frame_id_eq and frame_id_unwind. For instance, 141 in the above, to determine that A stepped-into B, the equation 142 "A.id != B.id && A.id == id_unwind (B)" can be used. */ 143 144/* For convenience. All fields are zero. */ 145extern const struct frame_id null_frame_id; 146 147/* Construct a frame ID. The first parameter is the frame's constant 148 stack address (typically the outer-bound), and the second the 149 frame's constant code address (typically the entry point). 150 The special identifier address is set to indicate a wild card. */ 151extern struct frame_id frame_id_build (CORE_ADDR stack_addr, 152 CORE_ADDR code_addr); 153 154/* Construct a special frame ID. The first parameter is the frame's constant 155 stack address (typically the outer-bound), the second is the 156 frame's constant code address (typically the entry point), 157 and the third parameter is the frame's special identifier address. */ 158extern struct frame_id frame_id_build_special (CORE_ADDR stack_addr, 159 CORE_ADDR code_addr, 160 CORE_ADDR special_addr); 161 162/* Construct a wild card frame ID. The parameter is the frame's constant 163 stack address (typically the outer-bound). The code address as well 164 as the special identifier address are set to indicate wild cards. */ 165extern struct frame_id frame_id_build_wild (CORE_ADDR stack_addr); 166 167/* Returns non-zero when L is a valid frame (a valid frame has a 168 non-zero .base). */ 169extern int frame_id_p (struct frame_id l); 170 171/* Returns non-zero when L and R identify the same frame, or, if 172 either L or R have a zero .func, then the same frame base. */ 173extern int frame_id_eq (struct frame_id l, struct frame_id r); 174 175/* Returns non-zero when L is strictly inner-than R (they have 176 different frame .bases). Neither L, nor R can be `null'. See note 177 above about frameless functions. */ 178extern int frame_id_inner (struct frame_id l, struct frame_id r); 179 180/* Write the internal representation of a frame ID on the specified 181 stream. */ 182extern void fprint_frame_id (struct ui_file *file, struct frame_id id); 183 184 185/* Frame types. Some are real, some are signal trampolines, and some 186 are completely artificial (dummy). */ 187 188enum frame_type 189{ 190 /* A true stack frame, created by the target program during normal 191 execution. */ 192 NORMAL_FRAME, 193 /* A fake frame, created by GDB when performing an inferior function 194 call. */ 195 DUMMY_FRAME, 196 /* In a signal handler, various OSs handle this in various ways. 197 The main thing is that the frame may be far from normal. */ 198 SIGTRAMP_FRAME, 199 /* Sentinel or registers frame. This frame obtains register values 200 direct from the inferior's registers. */ 201 SENTINEL_FRAME 202}; 203 204/* For every stopped thread, GDB tracks two frames: current and 205 selected. Current frame is the inner most frame of the selected 206 thread. Selected frame is the one being examined by the the GDB 207 CLI (selected using `up', `down', ...). The frames are created 208 on-demand (via get_prev_frame()) and then held in a frame cache. */ 209/* FIXME: cagney/2002-11-28: Er, there is a lie here. If you do the 210 sequence: `thread 1; up; thread 2; thread 1' you lose thread 1's 211 selected frame. At present GDB only tracks the selected frame of 212 the current thread. But be warned, that might change. */ 213/* FIXME: cagney/2002-11-14: At any time, only one thread's selected 214 and current frame can be active. Switching threads causes gdb to 215 discard all that cached frame information. Ulgh! Instead, current 216 and selected frame should be bound to a thread. */ 217 218/* On demand, create the inner most frame using information found in 219 the inferior. If the inner most frame can't be created, throw an 220 error. */ 221extern struct frame_info *get_current_frame (void); 222 223/* Invalidates the frame cache (this function should have been called 224 invalidate_cached_frames). 225 226 FIXME: cagney/2002-11-28: There should be two methods: one that 227 reverts the thread's selected frame back to current frame (for when 228 the inferior resumes) and one that does not (for when the user 229 modifies the target invalidating the frame cache). */ 230extern void reinit_frame_cache (void); 231 232/* On demand, create the selected frame and then return it. If the 233 selected frame can not be created, this function prints then throws 234 an error. When MESSAGE is non-NULL, use it for the error message, 235 otherwize use a generic error message. */ 236/* FIXME: cagney/2002-11-28: At present, when there is no selected 237 frame, this function always returns the current (inner most) frame. 238 It should instead, when a thread has previously had its frame 239 selected (but not resumed) and the frame cache invalidated, find 240 and then return that thread's previously selected frame. */ 241extern struct frame_info *get_selected_frame (const char *message); 242 243/* Select a specific frame. NULL, apparently implies re-select the 244 inner most frame. */ 245extern void select_frame (struct frame_info *); 246 247/* Given a FRAME, return the next (more inner, younger) or previous 248 (more outer, older) frame. */ 249extern struct frame_info *get_prev_frame (struct frame_info *); 250extern struct frame_info *get_next_frame (struct frame_info *); 251 252/* Given a frame's ID, relocate the frame. Returns NULL if the frame 253 is not found. */ 254extern struct frame_info *frame_find_by_id (struct frame_id id); 255 256/* Base attributes of a frame: */ 257 258/* The frame's `resume' address. Where the program will resume in 259 this frame. 260 261 This replaced: frame->pc; */ 262extern CORE_ADDR get_frame_pc (struct frame_info *); 263 264/* An address (not necessarily aligned to an instruction boundary) 265 that falls within THIS frame's code block. 266 267 When a function call is the last statement in a block, the return 268 address for the call may land at the start of the next block. 269 Similarly, if a no-return function call is the last statement in 270 the function, the return address may end up pointing beyond the 271 function, and possibly at the start of the next function. 272 273 These methods make an allowance for this. For call frames, this 274 function returns the frame's PC-1 which "should" be an address in 275 the frame's block. */ 276 277extern CORE_ADDR get_frame_address_in_block (struct frame_info *this_frame); 278 279/* Similar to get_frame_address_in_block, find an address in the 280 block which logically called NEXT_FRAME, assuming it is a THIS_TYPE 281 frame. */ 282 283extern CORE_ADDR frame_unwind_address_in_block (struct frame_info *next_frame, 284 enum frame_type this_type); 285 286/* The frame's inner-most bound. AKA the stack-pointer. Confusingly 287 known as top-of-stack. */ 288 289extern CORE_ADDR get_frame_sp (struct frame_info *); 290extern CORE_ADDR frame_sp_unwind (struct frame_info *); 291 292 293/* Following on from the `resume' address. Return the entry point 294 address of the function containing that resume address, or zero if 295 that function isn't known. */ 296extern CORE_ADDR get_frame_func (struct frame_info *fi); 297 298/* Similar to get_frame_func, find the start of the function which 299 logically called NEXT_FRAME, assuming it is a THIS_TYPE frame. */ 300extern CORE_ADDR frame_func_unwind (struct frame_info *next_frame, 301 enum frame_type this_type); 302 303/* Closely related to the resume address, various symbol table 304 attributes that are determined by the PC. Note that for a normal 305 frame, the PC refers to the resume address after the return, and 306 not the call instruction. In such a case, the address is adjusted 307 so that it (approximately) identifies the call site (and not the 308 return site). 309 310 NOTE: cagney/2002-11-28: The frame cache could be used to cache the 311 computed value. Working on the assumption that the bottle-neck is 312 in the single step code, and that code causes the frame cache to be 313 constantly flushed, caching things in a frame is probably of little 314 benefit. As they say `show us the numbers'. 315 316 NOTE: cagney/2002-11-28: Plenty more where this one came from: 317 find_frame_block(), find_frame_partial_function(), 318 find_frame_symtab(), find_frame_function(). Each will need to be 319 carefully considered to determine if the real intent was for it to 320 apply to the PC or the adjusted PC. */ 321extern void find_frame_sal (struct frame_info *frame, 322 struct symtab_and_line *sal); 323 324/* Set the current source and line to the location given by frame 325 FRAME, if possible. When CENTER is true, adjust so the relevant 326 line is in the center of the next 'list'. */ 327 328void set_current_sal_from_frame (struct frame_info *, int); 329 330/* Return the frame base (what ever that is) (DEPRECATED). 331 332 Old code was trying to use this single method for two conflicting 333 purposes. Such code needs to be updated to use either of: 334 335 get_frame_id: A low level frame unique identifier, that consists of 336 both a stack and a function address, that can be used to uniquely 337 identify a frame. This value is determined by the frame's 338 low-level unwinder, the stack part [typically] being the 339 top-of-stack of the previous frame, and the function part being the 340 function's start address. Since the correct identification of a 341 frameless function requires both the a stack and function address, 342 the old get_frame_base method was not sufficient. 343 344 get_frame_base_address: get_frame_locals_address: 345 get_frame_args_address: A set of high-level debug-info dependant 346 addresses that fall within the frame. These addresses almost 347 certainly will not match the stack address part of a frame ID (as 348 returned by get_frame_base). 349 350 This replaced: frame->frame; */ 351 352extern CORE_ADDR get_frame_base (struct frame_info *); 353 354/* Return the per-frame unique identifer. Can be used to relocate a 355 frame after a frame cache flush (and other similar operations). If 356 FI is NULL, return the null_frame_id. 357 358 NOTE: kettenis/20040508: These functions return a structure. On 359 platforms where structures are returned in static storage (vax, 360 m68k), this may trigger compiler bugs in code like: 361 362 if (frame_id_eq (get_frame_id (l), get_frame_id (r))) 363 364 where the return value from the first get_frame_id (l) gets 365 overwritten by the second get_frame_id (r). Please avoid writing 366 code like this. Use code like: 367 368 struct frame_id id = get_frame_id (l); 369 if (frame_id_eq (id, get_frame_id (r))) 370 371 instead, since that avoids the bug. */ 372extern struct frame_id get_frame_id (struct frame_info *fi); 373extern struct frame_id frame_unwind_id (struct frame_info *next_frame); 374 375/* Assuming that a frame is `normal', return its base-address, or 0 if 376 the information isn't available. NOTE: This address is really only 377 meaningful to the frame's high-level debug info. */ 378extern CORE_ADDR get_frame_base_address (struct frame_info *); 379 380/* Assuming that a frame is `normal', return the base-address of the 381 local variables, or 0 if the information isn't available. NOTE: 382 This address is really only meaningful to the frame's high-level 383 debug info. Typically, the argument and locals share a single 384 base-address. */ 385extern CORE_ADDR get_frame_locals_address (struct frame_info *); 386 387/* Assuming that a frame is `normal', return the base-address of the 388 parameter list, or 0 if that information isn't available. NOTE: 389 This address is really only meaningful to the frame's high-level 390 debug info. Typically, the argument and locals share a single 391 base-address. */ 392extern CORE_ADDR get_frame_args_address (struct frame_info *); 393 394/* The frame's level: 0 for innermost, 1 for its caller, ...; or -1 395 for an invalid frame). */ 396extern int frame_relative_level (struct frame_info *fi); 397 398/* Return the frame's type. */ 399 400extern enum frame_type get_frame_type (struct frame_info *); 401 402/* For frames where we can not unwind further, describe why. */ 403 404enum unwind_stop_reason 405 { 406 /* No particular reason; either we haven't tried unwinding yet, 407 or we didn't fail. */ 408 UNWIND_NO_REASON, 409 410 /* The previous frame's analyzer returns an invalid result 411 from this_id. 412 413 FIXME drow/2006-08-16: This is how GDB used to indicate end of 414 stack. We should migrate to a model where frames always have a 415 valid ID, and this becomes not just an error but an internal 416 error. But that's a project for another day. */ 417 UNWIND_NULL_ID, 418 419 /* All the conditions after this point are considered errors; 420 abnormal stack termination. If a backtrace stops for one 421 of these reasons, we'll let the user know. This marker 422 is not a valid stop reason. */ 423 UNWIND_FIRST_ERROR, 424 425 /* This frame ID looks like it ought to belong to a NEXT frame, 426 but we got it for a PREV frame. Normally, this is a sign of 427 unwinder failure. It could also indicate stack corruption. */ 428 UNWIND_INNER_ID, 429 430 /* This frame has the same ID as the previous one. That means 431 that unwinding further would almost certainly give us another 432 frame with exactly the same ID, so break the chain. Normally, 433 this is a sign of unwinder failure. It could also indicate 434 stack corruption. */ 435 UNWIND_SAME_ID, 436 437 /* The frame unwinder didn't find any saved PC, but we needed 438 one to unwind further. */ 439 UNWIND_NO_SAVED_PC, 440 }; 441 442/* Return the reason why we can't unwind past this frame. */ 443 444enum unwind_stop_reason get_frame_unwind_stop_reason (struct frame_info *); 445 446/* Translate a reason code to an informative string. */ 447 448const char *frame_stop_reason_string (enum unwind_stop_reason); 449 450/* Unwind the stack frame so that the value of REGNUM, in the previous 451 (up, older) frame is returned. If VALUEP is NULL, don't 452 fetch/compute the value. Instead just return the location of the 453 value. */ 454extern void frame_register_unwind (struct frame_info *frame, int regnum, 455 int *optimizedp, enum lval_type *lvalp, 456 CORE_ADDR *addrp, int *realnump, 457 gdb_byte *valuep); 458 459/* Fetch a register from this, or unwind a register from the next 460 frame. Note that the get_frame methods are wrappers to 461 frame->next->unwind. They all [potentially] throw an error if the 462 fetch fails. */ 463 464extern void frame_unwind_register (struct frame_info *frame, 465 int regnum, gdb_byte *buf); 466extern void get_frame_register (struct frame_info *frame, 467 int regnum, gdb_byte *buf); 468 469extern LONGEST frame_unwind_register_signed (struct frame_info *frame, 470 int regnum); 471extern LONGEST get_frame_register_signed (struct frame_info *frame, 472 int regnum); 473extern ULONGEST frame_unwind_register_unsigned (struct frame_info *frame, 474 int regnum); 475extern ULONGEST get_frame_register_unsigned (struct frame_info *frame, 476 int regnum); 477 478 479/* Use frame_unwind_register_signed. */ 480extern void frame_unwind_unsigned_register (struct frame_info *frame, 481 int regnum, ULONGEST *val); 482 483/* Get the value of the register that belongs to this FRAME. This 484 function is a wrapper to the call sequence ``frame_register_unwind 485 (get_next_frame (FRAME))''. As per frame_register_unwind(), if 486 VALUEP is NULL, the registers value is not fetched/computed. */ 487 488extern void frame_register (struct frame_info *frame, int regnum, 489 int *optimizedp, enum lval_type *lvalp, 490 CORE_ADDR *addrp, int *realnump, 491 gdb_byte *valuep); 492 493/* The reverse. Store a register value relative to the specified 494 frame. Note: this call makes the frame's state undefined. The 495 register and frame caches must be flushed. */ 496extern void put_frame_register (struct frame_info *frame, int regnum, 497 const gdb_byte *buf); 498 499/* Read LEN bytes from one or multiple registers starting with REGNUM 500 in frame FRAME, starting at OFFSET, into BUF. */ 501extern int get_frame_register_bytes (struct frame_info *frame, int regnum, 502 CORE_ADDR offset, int len, 503 gdb_byte *myaddr); 504 505/* Write LEN bytes to one or multiple registers starting with REGNUM 506 in frame FRAME, starting at OFFSET, into BUF. */ 507extern void put_frame_register_bytes (struct frame_info *frame, int regnum, 508 CORE_ADDR offset, int len, 509 const gdb_byte *myaddr); 510 511/* Map between a frame register number and its name. A frame register 512 space is a superset of the cooked register space --- it also 513 includes builtin registers. If NAMELEN is negative, use the NAME's 514 length when doing the comparison. */ 515 516extern int frame_map_name_to_regnum (struct frame_info *frame, 517 const char *name, int namelen); 518extern const char *frame_map_regnum_to_name (struct frame_info *frame, 519 int regnum); 520 521/* Unwind the PC. Strictly speaking return the resume address of the 522 calling frame. For GDB, `pc' is the resume address and not a 523 specific register. */ 524 525extern CORE_ADDR frame_pc_unwind (struct frame_info *frame); 526 527/* Discard the specified frame. Restoring the registers to the state 528 of the caller. */ 529extern void frame_pop (struct frame_info *frame); 530 531/* Return memory from the specified frame. A frame knows its thread / 532 LWP and hence can find its way down to a target. The assumption 533 here is that the current and previous frame share a common address 534 space. 535 536 If the memory read fails, these methods throw an error. 537 538 NOTE: cagney/2003-06-03: Should there be unwind versions of these 539 methods? That isn't clear. Can code, for instance, assume that 540 this and the previous frame's memory or architecture are identical? 541 If architecture / memory changes are always separated by special 542 adaptor frames this should be ok. */ 543 544extern void get_frame_memory (struct frame_info *this_frame, CORE_ADDR addr, 545 gdb_byte *buf, int len); 546extern LONGEST get_frame_memory_signed (struct frame_info *this_frame, 547 CORE_ADDR memaddr, int len); 548extern ULONGEST get_frame_memory_unsigned (struct frame_info *this_frame, 549 CORE_ADDR memaddr, int len); 550 551/* Same as above, but return non-zero when the entire memory read 552 succeeds, zero otherwize. */ 553extern int safe_frame_unwind_memory (struct frame_info *this_frame, 554 CORE_ADDR addr, gdb_byte *buf, int len); 555 556/* Return this frame's architecture. */ 557 558extern struct gdbarch *get_frame_arch (struct frame_info *this_frame); 559 560 561/* Values for the source flag to be used in print_frame_info_base(). */ 562enum print_what 563 { 564 /* Print only the source line, like in stepi. */ 565 SRC_LINE = -1, 566 /* Print only the location, i.e. level, address (sometimes) 567 function, args, file, line, line num. */ 568 LOCATION, 569 /* Print both of the above. */ 570 SRC_AND_LOC, 571 /* Print location only, but always include the address. */ 572 LOC_AND_ADDRESS 573 }; 574 575/* Allocate additional space for appendices to a struct frame_info. 576 NOTE: Much of GDB's code works on the assumption that the allocated 577 saved_regs[] array is the size specified below. If you try to make 578 that array smaller, GDB will happily walk off its end. */ 579 580#ifdef SIZEOF_FRAME_SAVED_REGS 581#error "SIZEOF_FRAME_SAVED_REGS can not be re-defined" 582#endif 583#define SIZEOF_FRAME_SAVED_REGS \ 584 (sizeof (CORE_ADDR) * (gdbarch_num_regs (current_gdbarch)\ 585 + gdbarch_num_pseudo_regs (current_gdbarch))) 586 587/* Allocate zero initialized memory from the frame cache obstack. 588 Appendices to the frame info (such as the unwind cache) should 589 allocate memory using this method. */ 590 591extern void *frame_obstack_zalloc (unsigned long size); 592#define FRAME_OBSTACK_ZALLOC(TYPE) ((TYPE *) frame_obstack_zalloc (sizeof (TYPE))) 593#define FRAME_OBSTACK_CALLOC(NUMBER,TYPE) ((TYPE *) frame_obstack_zalloc ((NUMBER) * sizeof (TYPE))) 594 595/* Create a regcache, and copy the frame's registers into it. */ 596struct regcache *frame_save_as_regcache (struct frame_info *this_frame); 597 598extern struct block *get_frame_block (struct frame_info *, 599 CORE_ADDR *addr_in_block); 600 601/* Return the `struct block' that belongs to the selected thread's 602 selected frame. If the inferior has no state, return NULL. 603 604 NOTE: cagney/2002-11-29: 605 606 No state? Does the inferior have any execution state (a core file 607 does, an executable does not). At present the code tests 608 `target_has_stack' but I'm left wondering if it should test 609 `target_has_registers' or, even, a merged target_has_state. 610 611 Should it look at the most recently specified SAL? If the target 612 has no state, should this function try to extract a block from the 613 most recently selected SAL? That way `list foo' would give it some 614 sort of reference point. Then again, perhaps that would confuse 615 things. 616 617 Calls to this function can be broken down into two categories: Code 618 that uses the selected block as an additional, but optional, data 619 point; Code that uses the selected block as a prop, when it should 620 have the relevant frame/block/pc explicitly passed in. 621 622 The latter can be eliminated by correctly parameterizing the code, 623 the former though is more interesting. Per the "address" command, 624 it occurs in the CLI code and makes it possible for commands to 625 work, even when the inferior has no state. */ 626 627extern struct block *get_selected_block (CORE_ADDR *addr_in_block); 628 629extern struct symbol *get_frame_function (struct frame_info *); 630 631extern CORE_ADDR get_pc_function_start (CORE_ADDR); 632 633extern struct frame_info *find_relative_frame (struct frame_info *, int *); 634 635extern void show_and_print_stack_frame (struct frame_info *fi, int print_level, 636 enum print_what print_what); 637 638extern void print_stack_frame (struct frame_info *, int print_level, 639 enum print_what print_what); 640 641extern void show_stack_frame (struct frame_info *); 642 643extern void print_frame_info (struct frame_info *, int print_level, 644 enum print_what print_what, int args); 645 646extern struct frame_info *block_innermost_frame (struct block *); 647 648extern int deprecated_pc_in_call_dummy (CORE_ADDR pc); 649 650/* FIXME: cagney/2003-02-02: Should be deprecated or replaced with a 651 function called get_frame_register_p(). This slightly weird (and 652 older) variant of get_frame_register() returns zero (indicating the 653 register is unavailable) if either: the register isn't cached; or 654 the register has been optimized out. Problem is, neither check is 655 exactly correct. A register can't be optimized out (it may not 656 have been saved as part of a function call); The fact that a 657 register isn't in the register cache doesn't mean that the register 658 isn't available (it could have been fetched from memory). */ 659 660extern int frame_register_read (struct frame_info *frame, int regnum, 661 gdb_byte *buf); 662 663/* From stack.c. */ 664extern void args_info (char *, int); 665 666extern void locals_info (char *, int); 667 668extern void (*deprecated_selected_frame_level_changed_hook) (int); 669 670extern void return_command (char *, int); 671 672 673/* Notes (cagney/2002-11-27, drow/2003-09-06): 674 675 You might think that calls to this function can simply be replaced by a 676 call to get_selected_frame(). 677 678 Unfortunately, it isn't that easy. 679 680 The relevant code needs to be audited to determine if it is 681 possible (or practical) to instead pass the applicable frame in as a 682 parameter. For instance, DEPRECATED_DO_REGISTERS_INFO() relied on 683 the deprecated_selected_frame global, while its replacement, 684 PRINT_REGISTERS_INFO(), is parameterized with the selected frame. 685 The only real exceptions occur at the edge (in the CLI code) where 686 user commands need to pick up the selected frame before proceeding. 687 688 There are also some functions called with a NULL frame meaning either "the 689 program is not running" or "use the selected frame". 690 691 This is important. GDB is trying to stamp out the hack: 692 693 saved_frame = deprecated_safe_get_selected_frame (); 694 select_frame (...); 695 hack_using_global_selected_frame (); 696 select_frame (saved_frame); 697 698 Take care! 699 700 This function calls get_selected_frame if the inferior should have a 701 frame, or returns NULL otherwise. */ 702 703extern struct frame_info *deprecated_safe_get_selected_frame (void); 704 705/* Create a frame using the specified BASE and PC. */ 706 707extern struct frame_info *create_new_frame (CORE_ADDR base, CORE_ADDR pc); 708 709/* FIXME: cagney/2002-12-06: Has the PC in the current frame changed? 710 "infrun.c", Thanks to gdbarch_decr_pc_after_break, can change the PC after 711 the initial frame create. This puts things back in sync. 712 713 This replaced: frame->pc = ....; */ 714extern void deprecated_update_frame_pc_hack (struct frame_info *frame, 715 CORE_ADDR pc); 716 717/* FIXME: cagney/2002-12-18: Has the frame's base changed? Or to be 718 more exact, was that initial guess at the frame's base as returned 719 by the deleted read_fp() wrong? If it was, fix it. This shouldn't 720 be necessary since the code should be getting the frame's base 721 correct from the outset. 722 723 This replaced: frame->frame = ....; */ 724extern void deprecated_update_frame_base_hack (struct frame_info *frame, 725 CORE_ADDR base); 726 727#endif /* !defined (FRAME_H) */ 728