43de3b1f095a1bf7c4735c9ca617e011f26c11db
[deliverable/binutils-gdb.git] / gdb / arm-tdep.c
1 /* Common target dependent code for GDB on ARM systems.
2 Copyright 1988, 1989, 1991, 1992, 1993, 1995, 1996, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
4
5 This file is part of GDB.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
21
22 #include <ctype.h> /* XXX for isupper () */
23
24 #include "defs.h"
25 #include "frame.h"
26 #include "inferior.h"
27 #include "gdbcmd.h"
28 #include "gdbcore.h"
29 #include "gdb_string.h"
30 #include "dis-asm.h" /* For register styles. */
31 #include "regcache.h"
32 #include "doublest.h"
33 #include "value.h"
34 #include "arch-utils.h"
35 #include "osabi.h"
36 #include "frame-unwind.h"
37 #include "frame-base.h"
38 #include "trad-frame.h"
39
40 #include "arm-tdep.h"
41 #include "gdb/sim-arm.h"
42
43 #include "elf-bfd.h"
44 #include "coff/internal.h"
45 #include "elf/arm.h"
46
47 #include "gdb_assert.h"
48
49 static int arm_debug;
50
51 /* Each OS has a different mechanism for accessing the various
52 registers stored in the sigcontext structure.
53
54 SIGCONTEXT_REGISTER_ADDRESS should be defined to the name (or
55 function pointer) which may be used to determine the addresses
56 of the various saved registers in the sigcontext structure.
57
58 For the ARM target, there are three parameters to this function.
59 The first is the pc value of the frame under consideration, the
60 second the stack pointer of this frame, and the last is the
61 register number to fetch.
62
63 If the tm.h file does not define this macro, then it's assumed that
64 no mechanism is needed and we define SIGCONTEXT_REGISTER_ADDRESS to
65 be 0.
66
67 When it comes time to multi-arching this code, see the identically
68 named machinery in ia64-tdep.c for an example of how it could be
69 done. It should not be necessary to modify the code below where
70 this macro is used. */
71
72 #ifdef SIGCONTEXT_REGISTER_ADDRESS
73 #ifndef SIGCONTEXT_REGISTER_ADDRESS_P
74 #define SIGCONTEXT_REGISTER_ADDRESS_P() 1
75 #endif
76 #else
77 #define SIGCONTEXT_REGISTER_ADDRESS(SP,PC,REG) 0
78 #define SIGCONTEXT_REGISTER_ADDRESS_P() 0
79 #endif
80
81 /* Macros for setting and testing a bit in a minimal symbol that marks
82 it as Thumb function. The MSB of the minimal symbol's "info" field
83 is used for this purpose.
84
85 MSYMBOL_SET_SPECIAL Actually sets the "special" bit.
86 MSYMBOL_IS_SPECIAL Tests the "special" bit in a minimal symbol. */
87
88 #define MSYMBOL_SET_SPECIAL(msym) \
89 MSYMBOL_INFO (msym) = (char *) (((long) MSYMBOL_INFO (msym)) \
90 | 0x80000000)
91
92 #define MSYMBOL_IS_SPECIAL(msym) \
93 (((long) MSYMBOL_INFO (msym) & 0x80000000) != 0)
94
95 /* The list of available "set arm ..." and "show arm ..." commands. */
96 static struct cmd_list_element *setarmcmdlist = NULL;
97 static struct cmd_list_element *showarmcmdlist = NULL;
98
99 /* The type of floating-point to use. Keep this in sync with enum
100 arm_float_model, and the help string in _initialize_arm_tdep. */
101 static const char *fp_model_strings[] =
102 {
103 "auto",
104 "softfpa",
105 "fpa",
106 "softvfp",
107 "vfp"
108 };
109
110 /* A variable that can be configured by the user. */
111 static enum arm_float_model arm_fp_model = ARM_FLOAT_AUTO;
112 static const char *current_fp_model = "auto";
113
114 /* Number of different reg name sets (options). */
115 static int num_disassembly_options;
116
117 /* We have more registers than the disassembler as gdb can print the value
118 of special registers as well.
119 The general register names are overwritten by whatever is being used by
120 the disassembler at the moment. We also adjust the case of cpsr and fps. */
121
122 /* Initial value: Register names used in ARM's ISA documentation. */
123 static char * arm_register_name_strings[] =
124 {"r0", "r1", "r2", "r3", /* 0 1 2 3 */
125 "r4", "r5", "r6", "r7", /* 4 5 6 7 */
126 "r8", "r9", "r10", "r11", /* 8 9 10 11 */
127 "r12", "sp", "lr", "pc", /* 12 13 14 15 */
128 "f0", "f1", "f2", "f3", /* 16 17 18 19 */
129 "f4", "f5", "f6", "f7", /* 20 21 22 23 */
130 "fps", "cpsr" }; /* 24 25 */
131 static char **arm_register_names = arm_register_name_strings;
132
133 /* Valid register name styles. */
134 static const char **valid_disassembly_styles;
135
136 /* Disassembly style to use. Default to "std" register names. */
137 static const char *disassembly_style;
138 /* Index to that option in the opcodes table. */
139 static int current_option;
140
141 /* This is used to keep the bfd arch_info in sync with the disassembly
142 style. */
143 static void set_disassembly_style_sfunc(char *, int,
144 struct cmd_list_element *);
145 static void set_disassembly_style (void);
146
147 static void convert_from_extended (const struct floatformat *, const void *,
148 void *);
149 static void convert_to_extended (const struct floatformat *, void *,
150 const void *);
151
152 struct arm_prologue_cache
153 {
154 /* The stack pointer at the time this frame was created; i.e. the
155 caller's stack pointer when this function was called. It is used
156 to identify this frame. */
157 CORE_ADDR prev_sp;
158
159 /* The frame base for this frame is just prev_sp + frame offset -
160 frame size. FRAMESIZE is the size of this stack frame, and
161 FRAMEOFFSET if the initial offset from the stack pointer (this
162 frame's stack pointer, not PREV_SP) to the frame base. */
163
164 int framesize;
165 int frameoffset;
166
167 /* The register used to hold the frame pointer for this frame. */
168 int framereg;
169
170 /* Saved register offsets. */
171 struct trad_frame_saved_reg *saved_regs;
172 };
173
174 /* Addresses for calling Thumb functions have the bit 0 set.
175 Here are some macros to test, set, or clear bit 0 of addresses. */
176 #define IS_THUMB_ADDR(addr) ((addr) & 1)
177 #define MAKE_THUMB_ADDR(addr) ((addr) | 1)
178 #define UNMAKE_THUMB_ADDR(addr) ((addr) & ~1)
179
180 /* Set to true if the 32-bit mode is in use. */
181
182 int arm_apcs_32 = 1;
183
184 /* Flag set by arm_fix_call_dummy that tells whether the target
185 function is a Thumb function. This flag is checked by
186 arm_push_arguments. FIXME: Change the PUSH_ARGUMENTS macro (and
187 its use in valops.c) to pass the function address as an additional
188 parameter. */
189
190 static int target_is_thumb;
191
192 /* Flag set by arm_fix_call_dummy that tells whether the calling
193 function is a Thumb function. This flag is checked by
194 arm_pc_is_thumb. */
195
196 static int caller_is_thumb;
197
198 /* Determine if the program counter specified in MEMADDR is in a Thumb
199 function. */
200
201 int
202 arm_pc_is_thumb (CORE_ADDR memaddr)
203 {
204 struct minimal_symbol *sym;
205
206 /* If bit 0 of the address is set, assume this is a Thumb address. */
207 if (IS_THUMB_ADDR (memaddr))
208 return 1;
209
210 /* Thumb functions have a "special" bit set in minimal symbols. */
211 sym = lookup_minimal_symbol_by_pc (memaddr);
212 if (sym)
213 {
214 return (MSYMBOL_IS_SPECIAL (sym));
215 }
216 else
217 {
218 return 0;
219 }
220 }
221
222 /* Determine if the program counter specified in MEMADDR is in a call
223 dummy being called from a Thumb function. */
224
225 int
226 arm_pc_is_thumb_dummy (CORE_ADDR memaddr)
227 {
228 CORE_ADDR sp = read_sp ();
229
230 /* FIXME: Until we switch for the new call dummy macros, this heuristic
231 is the best we can do. We are trying to determine if the pc is on
232 the stack, which (hopefully) will only happen in a call dummy.
233 We hope the current stack pointer is not so far alway from the dummy
234 frame location (true if we have not pushed large data structures or
235 gone too many levels deep) and that our 1024 is not enough to consider
236 code regions as part of the stack (true for most practical purposes). */
237 if (deprecated_pc_in_call_dummy (memaddr))
238 return caller_is_thumb;
239 else
240 return 0;
241 }
242
243 /* Remove useless bits from addresses in a running program. */
244 static CORE_ADDR
245 arm_addr_bits_remove (CORE_ADDR val)
246 {
247 if (arm_apcs_32)
248 return (val & (arm_pc_is_thumb (val) ? 0xfffffffe : 0xfffffffc));
249 else
250 return (val & 0x03fffffc);
251 }
252
253 /* When reading symbols, we need to zap the low bit of the address,
254 which may be set to 1 for Thumb functions. */
255 static CORE_ADDR
256 arm_smash_text_address (CORE_ADDR val)
257 {
258 return val & ~1;
259 }
260
261 /* Immediately after a function call, return the saved pc. Can't
262 always go through the frames for this because on some machines the
263 new frame is not set up until the new function executes some
264 instructions. */
265
266 static CORE_ADDR
267 arm_saved_pc_after_call (struct frame_info *frame)
268 {
269 return ADDR_BITS_REMOVE (read_register (ARM_LR_REGNUM));
270 }
271
272 /* A typical Thumb prologue looks like this:
273 push {r7, lr}
274 add sp, sp, #-28
275 add r7, sp, #12
276 Sometimes the latter instruction may be replaced by:
277 mov r7, sp
278
279 or like this:
280 push {r7, lr}
281 mov r7, sp
282 sub sp, #12
283
284 or, on tpcs, like this:
285 sub sp,#16
286 push {r7, lr}
287 (many instructions)
288 mov r7, sp
289 sub sp, #12
290
291 There is always one instruction of three classes:
292 1 - push
293 2 - setting of r7
294 3 - adjusting of sp
295
296 When we have found at least one of each class we are done with the prolog.
297 Note that the "sub sp, #NN" before the push does not count.
298 */
299
300 static CORE_ADDR
301 thumb_skip_prologue (CORE_ADDR pc, CORE_ADDR func_end)
302 {
303 CORE_ADDR current_pc;
304 /* findmask:
305 bit 0 - push { rlist }
306 bit 1 - mov r7, sp OR add r7, sp, #imm (setting of r7)
307 bit 2 - sub sp, #simm OR add sp, #simm (adjusting of sp)
308 */
309 int findmask = 0;
310
311 for (current_pc = pc;
312 current_pc + 2 < func_end && current_pc < pc + 40;
313 current_pc += 2)
314 {
315 unsigned short insn = read_memory_unsigned_integer (current_pc, 2);
316
317 if ((insn & 0xfe00) == 0xb400) /* push { rlist } */
318 {
319 findmask |= 1; /* push found */
320 }
321 else if ((insn & 0xff00) == 0xb000) /* add sp, #simm OR
322 sub sp, #simm */
323 {
324 if ((findmask & 1) == 0) /* before push ? */
325 continue;
326 else
327 findmask |= 4; /* add/sub sp found */
328 }
329 else if ((insn & 0xff00) == 0xaf00) /* add r7, sp, #imm */
330 {
331 findmask |= 2; /* setting of r7 found */
332 }
333 else if (insn == 0x466f) /* mov r7, sp */
334 {
335 findmask |= 2; /* setting of r7 found */
336 }
337 else if (findmask == (4+2+1))
338 {
339 /* We have found one of each type of prologue instruction */
340 break;
341 }
342 else
343 /* Something in the prolog that we don't care about or some
344 instruction from outside the prolog scheduled here for
345 optimization. */
346 continue;
347 }
348
349 return current_pc;
350 }
351
352 /* Advance the PC across any function entry prologue instructions to
353 reach some "real" code.
354
355 The APCS (ARM Procedure Call Standard) defines the following
356 prologue:
357
358 mov ip, sp
359 [stmfd sp!, {a1,a2,a3,a4}]
360 stmfd sp!, {...,fp,ip,lr,pc}
361 [stfe f7, [sp, #-12]!]
362 [stfe f6, [sp, #-12]!]
363 [stfe f5, [sp, #-12]!]
364 [stfe f4, [sp, #-12]!]
365 sub fp, ip, #nn @@ nn == 20 or 4 depending on second insn */
366
367 static CORE_ADDR
368 arm_skip_prologue (CORE_ADDR pc)
369 {
370 unsigned long inst;
371 CORE_ADDR skip_pc;
372 CORE_ADDR func_addr, func_end = 0;
373 char *func_name;
374 struct symtab_and_line sal;
375
376 /* If we're in a dummy frame, don't even try to skip the prologue. */
377 if (deprecated_pc_in_call_dummy (pc))
378 return pc;
379
380 /* See what the symbol table says. */
381
382 if (find_pc_partial_function (pc, &func_name, &func_addr, &func_end))
383 {
384 struct symbol *sym;
385
386 /* Found a function. */
387 sym = lookup_symbol (func_name, NULL, VAR_DOMAIN, NULL, NULL);
388 if (sym && SYMBOL_LANGUAGE (sym) != language_asm)
389 {
390 /* Don't use this trick for assembly source files. */
391 sal = find_pc_line (func_addr, 0);
392 if ((sal.line != 0) && (sal.end < func_end))
393 return sal.end;
394 }
395 }
396
397 /* Check if this is Thumb code. */
398 if (arm_pc_is_thumb (pc))
399 return thumb_skip_prologue (pc, func_end);
400
401 /* Can't find the prologue end in the symbol table, try it the hard way
402 by disassembling the instructions. */
403
404 /* Like arm_scan_prologue, stop no later than pc + 64. */
405 if (func_end == 0 || func_end > pc + 64)
406 func_end = pc + 64;
407
408 for (skip_pc = pc; skip_pc < func_end; skip_pc += 4)
409 {
410 inst = read_memory_integer (skip_pc, 4);
411
412 /* "mov ip, sp" is no longer a required part of the prologue. */
413 if (inst == 0xe1a0c00d) /* mov ip, sp */
414 continue;
415
416 if ((inst & 0xfffff000) == 0xe28dc000) /* add ip, sp #n */
417 continue;
418
419 if ((inst & 0xfffff000) == 0xe24dc000) /* sub ip, sp #n */
420 continue;
421
422 /* Some prologues begin with "str lr, [sp, #-4]!". */
423 if (inst == 0xe52de004) /* str lr, [sp, #-4]! */
424 continue;
425
426 if ((inst & 0xfffffff0) == 0xe92d0000) /* stmfd sp!,{a1,a2,a3,a4} */
427 continue;
428
429 if ((inst & 0xfffff800) == 0xe92dd800) /* stmfd sp!,{fp,ip,lr,pc} */
430 continue;
431
432 /* Any insns after this point may float into the code, if it makes
433 for better instruction scheduling, so we skip them only if we
434 find them, but still consider the function to be frame-ful. */
435
436 /* We may have either one sfmfd instruction here, or several stfe
437 insns, depending on the version of floating point code we
438 support. */
439 if ((inst & 0xffbf0fff) == 0xec2d0200) /* sfmfd fn, <cnt>, [sp]! */
440 continue;
441
442 if ((inst & 0xffff8fff) == 0xed6d0103) /* stfe fn, [sp, #-12]! */
443 continue;
444
445 if ((inst & 0xfffff000) == 0xe24cb000) /* sub fp, ip, #nn */
446 continue;
447
448 if ((inst & 0xfffff000) == 0xe24dd000) /* sub sp, sp, #nn */
449 continue;
450
451 if ((inst & 0xffffc000) == 0xe54b0000 || /* strb r(0123),[r11,#-nn] */
452 (inst & 0xffffc0f0) == 0xe14b00b0 || /* strh r(0123),[r11,#-nn] */
453 (inst & 0xffffc000) == 0xe50b0000) /* str r(0123),[r11,#-nn] */
454 continue;
455
456 if ((inst & 0xffffc000) == 0xe5cd0000 || /* strb r(0123),[sp,#nn] */
457 (inst & 0xffffc0f0) == 0xe1cd00b0 || /* strh r(0123),[sp,#nn] */
458 (inst & 0xffffc000) == 0xe58d0000) /* str r(0123),[sp,#nn] */
459 continue;
460
461 /* Un-recognized instruction; stop scanning. */
462 break;
463 }
464
465 return skip_pc; /* End of prologue */
466 }
467
468 /* *INDENT-OFF* */
469 /* Function: thumb_scan_prologue (helper function for arm_scan_prologue)
470 This function decodes a Thumb function prologue to determine:
471 1) the size of the stack frame
472 2) which registers are saved on it
473 3) the offsets of saved regs
474 4) the offset from the stack pointer to the frame pointer
475
476 A typical Thumb function prologue would create this stack frame
477 (offsets relative to FP)
478 old SP -> 24 stack parameters
479 20 LR
480 16 R7
481 R7 -> 0 local variables (16 bytes)
482 SP -> -12 additional stack space (12 bytes)
483 The frame size would thus be 36 bytes, and the frame offset would be
484 12 bytes. The frame register is R7.
485
486 The comments for thumb_skip_prolog() describe the algorithm we use
487 to detect the end of the prolog. */
488 /* *INDENT-ON* */
489
490 static void
491 thumb_scan_prologue (CORE_ADDR prev_pc, struct arm_prologue_cache *cache)
492 {
493 CORE_ADDR prologue_start;
494 CORE_ADDR prologue_end;
495 CORE_ADDR current_pc;
496 /* Which register has been copied to register n? */
497 int saved_reg[16];
498 /* findmask:
499 bit 0 - push { rlist }
500 bit 1 - mov r7, sp OR add r7, sp, #imm (setting of r7)
501 bit 2 - sub sp, #simm OR add sp, #simm (adjusting of sp)
502 */
503 int findmask = 0;
504 int i;
505
506 if (find_pc_partial_function (prev_pc, NULL, &prologue_start, &prologue_end))
507 {
508 struct symtab_and_line sal = find_pc_line (prologue_start, 0);
509
510 if (sal.line == 0) /* no line info, use current PC */
511 prologue_end = prev_pc;
512 else if (sal.end < prologue_end) /* next line begins after fn end */
513 prologue_end = sal.end; /* (probably means no prologue) */
514 }
515 else
516 /* We're in the boondocks: allow for
517 16 pushes, an add, and "mv fp,sp". */
518 prologue_end = prologue_start + 40;
519
520 prologue_end = min (prologue_end, prev_pc);
521
522 /* Initialize the saved register map. When register H is copied to
523 register L, we will put H in saved_reg[L]. */
524 for (i = 0; i < 16; i++)
525 saved_reg[i] = i;
526
527 /* Search the prologue looking for instructions that set up the
528 frame pointer, adjust the stack pointer, and save registers.
529 Do this until all basic prolog instructions are found. */
530
531 cache->framesize = 0;
532 for (current_pc = prologue_start;
533 (current_pc < prologue_end) && ((findmask & 7) != 7);
534 current_pc += 2)
535 {
536 unsigned short insn;
537 int regno;
538 int offset;
539
540 insn = read_memory_unsigned_integer (current_pc, 2);
541
542 if ((insn & 0xfe00) == 0xb400) /* push { rlist } */
543 {
544 int mask;
545 findmask |= 1; /* push found */
546 /* Bits 0-7 contain a mask for registers R0-R7. Bit 8 says
547 whether to save LR (R14). */
548 mask = (insn & 0xff) | ((insn & 0x100) << 6);
549
550 /* Calculate offsets of saved R0-R7 and LR. */
551 for (regno = ARM_LR_REGNUM; regno >= 0; regno--)
552 if (mask & (1 << regno))
553 {
554 cache->framesize += 4;
555 cache->saved_regs[saved_reg[regno]].addr = -cache->framesize;
556 /* Reset saved register map. */
557 saved_reg[regno] = regno;
558 }
559 }
560 else if ((insn & 0xff00) == 0xb000) /* add sp, #simm OR
561 sub sp, #simm */
562 {
563 if ((findmask & 1) == 0) /* before push? */
564 continue;
565 else
566 findmask |= 4; /* add/sub sp found */
567
568 offset = (insn & 0x7f) << 2; /* get scaled offset */
569 if (insn & 0x80) /* is it signed? (==subtracting) */
570 {
571 cache->frameoffset += offset;
572 offset = -offset;
573 }
574 cache->framesize -= offset;
575 }
576 else if ((insn & 0xff00) == 0xaf00) /* add r7, sp, #imm */
577 {
578 findmask |= 2; /* setting of r7 found */
579 cache->framereg = THUMB_FP_REGNUM;
580 /* get scaled offset */
581 cache->frameoffset = (insn & 0xff) << 2;
582 }
583 else if (insn == 0x466f) /* mov r7, sp */
584 {
585 findmask |= 2; /* setting of r7 found */
586 cache->framereg = THUMB_FP_REGNUM;
587 cache->frameoffset = 0;
588 saved_reg[THUMB_FP_REGNUM] = ARM_SP_REGNUM;
589 }
590 else if ((insn & 0xffc0) == 0x4640) /* mov r0-r7, r8-r15 */
591 {
592 int lo_reg = insn & 7; /* dest. register (r0-r7) */
593 int hi_reg = ((insn >> 3) & 7) + 8; /* source register (r8-15) */
594 saved_reg[lo_reg] = hi_reg; /* remember hi reg was saved */
595 }
596 else
597 /* Something in the prolog that we don't care about or some
598 instruction from outside the prolog scheduled here for
599 optimization. */
600 continue;
601 }
602 }
603
604 /* This function decodes an ARM function prologue to determine:
605 1) the size of the stack frame
606 2) which registers are saved on it
607 3) the offsets of saved regs
608 4) the offset from the stack pointer to the frame pointer
609 This information is stored in the "extra" fields of the frame_info.
610
611 There are two basic forms for the ARM prologue. The fixed argument
612 function call will look like:
613
614 mov ip, sp
615 stmfd sp!, {fp, ip, lr, pc}
616 sub fp, ip, #4
617 [sub sp, sp, #4]
618
619 Which would create this stack frame (offsets relative to FP):
620 IP -> 4 (caller's stack)
621 FP -> 0 PC (points to address of stmfd instruction + 8 in callee)
622 -4 LR (return address in caller)
623 -8 IP (copy of caller's SP)
624 -12 FP (caller's FP)
625 SP -> -28 Local variables
626
627 The frame size would thus be 32 bytes, and the frame offset would be
628 28 bytes. The stmfd call can also save any of the vN registers it
629 plans to use, which increases the frame size accordingly.
630
631 Note: The stored PC is 8 off of the STMFD instruction that stored it
632 because the ARM Store instructions always store PC + 8 when you read
633 the PC register.
634
635 A variable argument function call will look like:
636
637 mov ip, sp
638 stmfd sp!, {a1, a2, a3, a4}
639 stmfd sp!, {fp, ip, lr, pc}
640 sub fp, ip, #20
641
642 Which would create this stack frame (offsets relative to FP):
643 IP -> 20 (caller's stack)
644 16 A4
645 12 A3
646 8 A2
647 4 A1
648 FP -> 0 PC (points to address of stmfd instruction + 8 in callee)
649 -4 LR (return address in caller)
650 -8 IP (copy of caller's SP)
651 -12 FP (caller's FP)
652 SP -> -28 Local variables
653
654 The frame size would thus be 48 bytes, and the frame offset would be
655 28 bytes.
656
657 There is another potential complication, which is that the optimizer
658 will try to separate the store of fp in the "stmfd" instruction from
659 the "sub fp, ip, #NN" instruction. Almost anything can be there, so
660 we just key on the stmfd, and then scan for the "sub fp, ip, #NN"...
661
662 Also, note, the original version of the ARM toolchain claimed that there
663 should be an
664
665 instruction at the end of the prologue. I have never seen GCC produce
666 this, and the ARM docs don't mention it. We still test for it below in
667 case it happens...
668
669 */
670
671 static void
672 arm_scan_prologue (struct frame_info *next_frame, struct arm_prologue_cache *cache)
673 {
674 int regno, sp_offset, fp_offset, ip_offset;
675 CORE_ADDR prologue_start, prologue_end, current_pc;
676 CORE_ADDR prev_pc = frame_pc_unwind (next_frame);
677
678 /* Assume there is no frame until proven otherwise. */
679 cache->framereg = ARM_SP_REGNUM;
680 cache->framesize = 0;
681 cache->frameoffset = 0;
682
683 /* Check for Thumb prologue. */
684 if (arm_pc_is_thumb (prev_pc))
685 {
686 thumb_scan_prologue (prev_pc, cache);
687 return;
688 }
689
690 /* Find the function prologue. If we can't find the function in
691 the symbol table, peek in the stack frame to find the PC. */
692 if (find_pc_partial_function (prev_pc, NULL, &prologue_start, &prologue_end))
693 {
694 /* One way to find the end of the prologue (which works well
695 for unoptimized code) is to do the following:
696
697 struct symtab_and_line sal = find_pc_line (prologue_start, 0);
698
699 if (sal.line == 0)
700 prologue_end = prev_pc;
701 else if (sal.end < prologue_end)
702 prologue_end = sal.end;
703
704 This mechanism is very accurate so long as the optimizer
705 doesn't move any instructions from the function body into the
706 prologue. If this happens, sal.end will be the last
707 instruction in the first hunk of prologue code just before
708 the first instruction that the scheduler has moved from
709 the body to the prologue.
710
711 In order to make sure that we scan all of the prologue
712 instructions, we use a slightly less accurate mechanism which
713 may scan more than necessary. To help compensate for this
714 lack of accuracy, the prologue scanning loop below contains
715 several clauses which'll cause the loop to terminate early if
716 an implausible prologue instruction is encountered.
717
718 The expression
719
720 prologue_start + 64
721
722 is a suitable endpoint since it accounts for the largest
723 possible prologue plus up to five instructions inserted by
724 the scheduler. */
725
726 if (prologue_end > prologue_start + 64)
727 {
728 prologue_end = prologue_start + 64; /* See above. */
729 }
730 }
731 else
732 {
733 /* We have no symbol information. Our only option is to assume this
734 function has a standard stack frame and the normal frame register.
735 Then, we can find the value of our frame pointer on entrance to
736 the callee (or at the present moment if this is the innermost frame).
737 The value stored there should be the address of the stmfd + 8. */
738 CORE_ADDR frame_loc;
739 LONGEST return_value;
740
741 frame_loc = frame_unwind_register_unsigned (next_frame, ARM_FP_REGNUM);
742 if (!safe_read_memory_integer (frame_loc, 4, &return_value))
743 return;
744 else
745 {
746 prologue_start = ADDR_BITS_REMOVE (return_value) - 8;
747 prologue_end = prologue_start + 64; /* See above. */
748 }
749 }
750
751 if (prev_pc < prologue_end)
752 prologue_end = prev_pc;
753
754 /* Now search the prologue looking for instructions that set up the
755 frame pointer, adjust the stack pointer, and save registers.
756
757 Be careful, however, and if it doesn't look like a prologue,
758 don't try to scan it. If, for instance, a frameless function
759 begins with stmfd sp!, then we will tell ourselves there is
760 a frame, which will confuse stack traceback, as well as "finish"
761 and other operations that rely on a knowledge of the stack
762 traceback.
763
764 In the APCS, the prologue should start with "mov ip, sp" so
765 if we don't see this as the first insn, we will stop.
766
767 [Note: This doesn't seem to be true any longer, so it's now an
768 optional part of the prologue. - Kevin Buettner, 2001-11-20]
769
770 [Note further: The "mov ip,sp" only seems to be missing in
771 frameless functions at optimization level "-O2" or above,
772 in which case it is often (but not always) replaced by
773 "str lr, [sp, #-4]!". - Michael Snyder, 2002-04-23] */
774
775 sp_offset = fp_offset = ip_offset = 0;
776
777 for (current_pc = prologue_start;
778 current_pc < prologue_end;
779 current_pc += 4)
780 {
781 unsigned int insn = read_memory_unsigned_integer (current_pc, 4);
782
783 if (insn == 0xe1a0c00d) /* mov ip, sp */
784 {
785 ip_offset = 0;
786 continue;
787 }
788 else if ((insn & 0xfffff000) == 0xe28dc000) /* add ip, sp #n */
789 {
790 unsigned imm = insn & 0xff; /* immediate value */
791 unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */
792 imm = (imm >> rot) | (imm << (32 - rot));
793 ip_offset = imm;
794 continue;
795 }
796 else if ((insn & 0xfffff000) == 0xe24dc000) /* sub ip, sp #n */
797 {
798 unsigned imm = insn & 0xff; /* immediate value */
799 unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */
800 imm = (imm >> rot) | (imm << (32 - rot));
801 ip_offset = -imm;
802 continue;
803 }
804 else if (insn == 0xe52de004) /* str lr, [sp, #-4]! */
805 {
806 sp_offset -= 4;
807 cache->saved_regs[ARM_LR_REGNUM].addr = sp_offset;
808 continue;
809 }
810 else if ((insn & 0xffff0000) == 0xe92d0000)
811 /* stmfd sp!, {..., fp, ip, lr, pc}
812 or
813 stmfd sp!, {a1, a2, a3, a4} */
814 {
815 int mask = insn & 0xffff;
816
817 /* Calculate offsets of saved registers. */
818 for (regno = ARM_PC_REGNUM; regno >= 0; regno--)
819 if (mask & (1 << regno))
820 {
821 sp_offset -= 4;
822 cache->saved_regs[regno].addr = sp_offset;
823 }
824 }
825 else if ((insn & 0xffffc000) == 0xe54b0000 || /* strb rx,[r11,#-n] */
826 (insn & 0xffffc0f0) == 0xe14b00b0 || /* strh rx,[r11,#-n] */
827 (insn & 0xffffc000) == 0xe50b0000) /* str rx,[r11,#-n] */
828 {
829 /* No need to add this to saved_regs -- it's just an arg reg. */
830 continue;
831 }
832 else if ((insn & 0xffffc000) == 0xe5cd0000 || /* strb rx,[sp,#n] */
833 (insn & 0xffffc0f0) == 0xe1cd00b0 || /* strh rx,[sp,#n] */
834 (insn & 0xffffc000) == 0xe58d0000) /* str rx,[sp,#n] */
835 {
836 /* No need to add this to saved_regs -- it's just an arg reg. */
837 continue;
838 }
839 else if ((insn & 0xfffff000) == 0xe24cb000) /* sub fp, ip #n */
840 {
841 unsigned imm = insn & 0xff; /* immediate value */
842 unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */
843 imm = (imm >> rot) | (imm << (32 - rot));
844 fp_offset = -imm + ip_offset;
845 cache->framereg = ARM_FP_REGNUM;
846 }
847 else if ((insn & 0xfffff000) == 0xe24dd000) /* sub sp, sp #n */
848 {
849 unsigned imm = insn & 0xff; /* immediate value */
850 unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */
851 imm = (imm >> rot) | (imm << (32 - rot));
852 sp_offset -= imm;
853 }
854 else if ((insn & 0xffff7fff) == 0xed6d0103) /* stfe f?, [sp, -#c]! */
855 {
856 sp_offset -= 12;
857 regno = ARM_F0_REGNUM + ((insn >> 12) & 0x07);
858 cache->saved_regs[regno].addr = sp_offset;
859 }
860 else if ((insn & 0xffbf0fff) == 0xec2d0200) /* sfmfd f0, 4, [sp!] */
861 {
862 int n_saved_fp_regs;
863 unsigned int fp_start_reg, fp_bound_reg;
864
865 if ((insn & 0x800) == 0x800) /* N0 is set */
866 {
867 if ((insn & 0x40000) == 0x40000) /* N1 is set */
868 n_saved_fp_regs = 3;
869 else
870 n_saved_fp_regs = 1;
871 }
872 else
873 {
874 if ((insn & 0x40000) == 0x40000) /* N1 is set */
875 n_saved_fp_regs = 2;
876 else
877 n_saved_fp_regs = 4;
878 }
879
880 fp_start_reg = ARM_F0_REGNUM + ((insn >> 12) & 0x7);
881 fp_bound_reg = fp_start_reg + n_saved_fp_regs;
882 for (; fp_start_reg < fp_bound_reg; fp_start_reg++)
883 {
884 sp_offset -= 12;
885 cache->saved_regs[fp_start_reg++].addr = sp_offset;
886 }
887 }
888 else if ((insn & 0xf0000000) != 0xe0000000)
889 break; /* Condition not true, exit early */
890 else if ((insn & 0xfe200000) == 0xe8200000) /* ldm? */
891 break; /* Don't scan past a block load */
892 else
893 /* The optimizer might shove anything into the prologue,
894 so we just skip what we don't recognize. */
895 continue;
896 }
897
898 /* The frame size is just the negative of the offset (from the
899 original SP) of the last thing thing we pushed on the stack.
900 The frame offset is [new FP] - [new SP]. */
901 cache->framesize = -sp_offset;
902 if (cache->framereg == ARM_FP_REGNUM)
903 cache->frameoffset = fp_offset - sp_offset;
904 else
905 cache->frameoffset = 0;
906 }
907
908 static struct arm_prologue_cache *
909 arm_make_prologue_cache (struct frame_info *next_frame)
910 {
911 int reg;
912 struct arm_prologue_cache *cache;
913 CORE_ADDR unwound_fp;
914
915 cache = frame_obstack_zalloc (sizeof (struct arm_prologue_cache));
916 cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
917
918 arm_scan_prologue (next_frame, cache);
919
920 unwound_fp = frame_unwind_register_unsigned (next_frame, cache->framereg);
921 if (unwound_fp == 0)
922 return cache;
923
924 cache->prev_sp = unwound_fp + cache->framesize - cache->frameoffset;
925
926 /* Calculate actual addresses of saved registers using offsets
927 determined by arm_scan_prologue. */
928 for (reg = 0; reg < NUM_REGS; reg++)
929 if (trad_frame_addr_p (cache->saved_regs, reg))
930 cache->saved_regs[reg].addr += cache->prev_sp;
931
932 return cache;
933 }
934
935 /* Our frame ID for a normal frame is the current function's starting PC
936 and the caller's SP when we were called. */
937
938 static void
939 arm_prologue_this_id (struct frame_info *next_frame,
940 void **this_cache,
941 struct frame_id *this_id)
942 {
943 struct arm_prologue_cache *cache;
944 struct frame_id id;
945 CORE_ADDR func;
946
947 if (*this_cache == NULL)
948 *this_cache = arm_make_prologue_cache (next_frame);
949 cache = *this_cache;
950
951 func = frame_func_unwind (next_frame);
952
953 /* This is meant to halt the backtrace at "_start". Make sure we
954 don't halt it at a generic dummy frame. */
955 if (func <= LOWEST_PC)
956 return;
957
958 /* If we've hit a wall, stop. */
959 if (cache->prev_sp == 0)
960 return;
961
962 id = frame_id_build (cache->prev_sp, func);
963 *this_id = id;
964 }
965
966 static void
967 arm_prologue_prev_register (struct frame_info *next_frame,
968 void **this_cache,
969 int prev_regnum,
970 int *optimized,
971 enum lval_type *lvalp,
972 CORE_ADDR *addrp,
973 int *realnump,
974 void *valuep)
975 {
976 struct arm_prologue_cache *cache;
977
978 if (*this_cache == NULL)
979 *this_cache = arm_make_prologue_cache (next_frame);
980 cache = *this_cache;
981
982 /* If we are asked to unwind the PC, then we need to return the LR
983 instead. The saved value of PC points into this frame's
984 prologue, not the next frame's resume location. */
985 if (prev_regnum == ARM_PC_REGNUM)
986 prev_regnum = ARM_LR_REGNUM;
987
988 /* SP is generally not saved to the stack, but this frame is
989 identified by NEXT_FRAME's stack pointer at the time of the call.
990 The value was already reconstructed into PREV_SP. */
991 if (prev_regnum == ARM_SP_REGNUM)
992 {
993 *lvalp = not_lval;
994 if (valuep)
995 store_unsigned_integer (valuep, 4, cache->prev_sp);
996 return;
997 }
998
999 trad_frame_get_prev_register (next_frame, cache->saved_regs, prev_regnum,
1000 optimized, lvalp, addrp, realnump, valuep);
1001 }
1002
1003 struct frame_unwind arm_prologue_unwind = {
1004 NORMAL_FRAME,
1005 arm_prologue_this_id,
1006 arm_prologue_prev_register
1007 };
1008
1009 static const struct frame_unwind *
1010 arm_prologue_unwind_sniffer (struct frame_info *next_frame)
1011 {
1012 return &arm_prologue_unwind;
1013 }
1014
1015 static CORE_ADDR
1016 arm_normal_frame_base (struct frame_info *next_frame, void **this_cache)
1017 {
1018 struct arm_prologue_cache *cache;
1019
1020 if (*this_cache == NULL)
1021 *this_cache = arm_make_prologue_cache (next_frame);
1022 cache = *this_cache;
1023
1024 return cache->prev_sp + cache->frameoffset - cache->framesize;
1025 }
1026
1027 struct frame_base arm_normal_base = {
1028 &arm_prologue_unwind,
1029 arm_normal_frame_base,
1030 arm_normal_frame_base,
1031 arm_normal_frame_base
1032 };
1033
1034 static struct arm_prologue_cache *
1035 arm_make_sigtramp_cache (struct frame_info *next_frame)
1036 {
1037 struct arm_prologue_cache *cache;
1038 int reg;
1039
1040 cache = frame_obstack_zalloc (sizeof (struct arm_prologue_cache));
1041
1042 cache->prev_sp = frame_unwind_register_unsigned (next_frame, ARM_SP_REGNUM);
1043
1044 cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
1045
1046 for (reg = 0; reg < NUM_REGS; reg++)
1047 cache->saved_regs[reg].addr
1048 = SIGCONTEXT_REGISTER_ADDRESS (cache->prev_sp,
1049 frame_pc_unwind (next_frame), reg);
1050
1051 /* FIXME: What about thumb mode? */
1052 cache->framereg = ARM_SP_REGNUM;
1053 cache->prev_sp
1054 = read_memory_integer (cache->saved_regs[cache->framereg].addr,
1055 register_size (current_gdbarch, cache->framereg));
1056
1057 return cache;
1058 }
1059
1060 static void
1061 arm_sigtramp_this_id (struct frame_info *next_frame,
1062 void **this_cache,
1063 struct frame_id *this_id)
1064 {
1065 struct arm_prologue_cache *cache;
1066
1067 if (*this_cache == NULL)
1068 *this_cache = arm_make_sigtramp_cache (next_frame);
1069 cache = *this_cache;
1070
1071 /* FIXME drow/2003-07-07: This isn't right if we single-step within
1072 the sigtramp frame; the PC should be the beginning of the trampoline. */
1073 *this_id = frame_id_build (cache->prev_sp, frame_pc_unwind (next_frame));
1074 }
1075
1076 static void
1077 arm_sigtramp_prev_register (struct frame_info *next_frame,
1078 void **this_cache,
1079 int prev_regnum,
1080 int *optimized,
1081 enum lval_type *lvalp,
1082 CORE_ADDR *addrp,
1083 int *realnump,
1084 void *valuep)
1085 {
1086 struct arm_prologue_cache *cache;
1087
1088 if (*this_cache == NULL)
1089 *this_cache = arm_make_sigtramp_cache (next_frame);
1090 cache = *this_cache;
1091
1092 trad_frame_get_prev_register (next_frame, cache->saved_regs, prev_regnum,
1093 optimized, lvalp, addrp, realnump, valuep);
1094 }
1095
1096 struct frame_unwind arm_sigtramp_unwind = {
1097 SIGTRAMP_FRAME,
1098 arm_sigtramp_this_id,
1099 arm_sigtramp_prev_register
1100 };
1101
1102 static const struct frame_unwind *
1103 arm_sigtramp_unwind_sniffer (struct frame_info *next_frame)
1104 {
1105 if (SIGCONTEXT_REGISTER_ADDRESS_P ()
1106 && legacy_pc_in_sigtramp (frame_pc_unwind (next_frame), (char *) 0))
1107 return &arm_sigtramp_unwind;
1108
1109 return NULL;
1110 }
1111
1112 /* Assuming NEXT_FRAME->prev is a dummy, return the frame ID of that
1113 dummy frame. The frame ID's base needs to match the TOS value
1114 saved by save_dummy_frame_tos() and returned from
1115 arm_push_dummy_call, and the PC needs to match the dummy frame's
1116 breakpoint. */
1117
1118 static struct frame_id
1119 arm_unwind_dummy_id (struct gdbarch *gdbarch, struct frame_info *next_frame)
1120 {
1121 return frame_id_build (frame_unwind_register_unsigned (next_frame, ARM_SP_REGNUM),
1122 frame_pc_unwind (next_frame));
1123 }
1124
1125 /* Given THIS_FRAME, find the previous frame's resume PC (which will
1126 be used to construct the previous frame's ID, after looking up the
1127 containing function). */
1128
1129 static CORE_ADDR
1130 arm_unwind_pc (struct gdbarch *gdbarch, struct frame_info *this_frame)
1131 {
1132 CORE_ADDR pc;
1133 pc = frame_unwind_register_unsigned (this_frame, ARM_PC_REGNUM);
1134 return IS_THUMB_ADDR (pc) ? UNMAKE_THUMB_ADDR (pc) : pc;
1135 }
1136
1137 static CORE_ADDR
1138 arm_unwind_sp (struct gdbarch *gdbarch, struct frame_info *this_frame)
1139 {
1140 return frame_unwind_register_unsigned (this_frame, ARM_SP_REGNUM);
1141 }
1142
1143 /* When arguments must be pushed onto the stack, they go on in reverse
1144 order. The code below implements a FILO (stack) to do this. */
1145
1146 struct stack_item
1147 {
1148 int len;
1149 struct stack_item *prev;
1150 void *data;
1151 };
1152
1153 static struct stack_item *
1154 push_stack_item (struct stack_item *prev, void *contents, int len)
1155 {
1156 struct stack_item *si;
1157 si = xmalloc (sizeof (struct stack_item));
1158 si->data = xmalloc (len);
1159 si->len = len;
1160 si->prev = prev;
1161 memcpy (si->data, contents, len);
1162 return si;
1163 }
1164
1165 static struct stack_item *
1166 pop_stack_item (struct stack_item *si)
1167 {
1168 struct stack_item *dead = si;
1169 si = si->prev;
1170 xfree (dead->data);
1171 xfree (dead);
1172 return si;
1173 }
1174
1175 /* We currently only support passing parameters in integer registers. This
1176 conforms with GCC's default model. Several other variants exist and
1177 we should probably support some of them based on the selected ABI. */
1178
1179 static CORE_ADDR
1180 arm_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
1181 struct regcache *regcache, CORE_ADDR bp_addr, int nargs,
1182 struct value **args, CORE_ADDR sp, int struct_return,
1183 CORE_ADDR struct_addr)
1184 {
1185 int argnum;
1186 int argreg;
1187 int nstack;
1188 struct stack_item *si = NULL;
1189
1190 /* Set the return address. For the ARM, the return breakpoint is
1191 always at BP_ADDR. */
1192 /* XXX Fix for Thumb. */
1193 regcache_cooked_write_unsigned (regcache, ARM_LR_REGNUM, bp_addr);
1194
1195 /* Walk through the list of args and determine how large a temporary
1196 stack is required. Need to take care here as structs may be
1197 passed on the stack, and we have to to push them. */
1198 nstack = 0;
1199
1200 argreg = ARM_A1_REGNUM;
1201 nstack = 0;
1202
1203 /* Some platforms require a double-word aligned stack. Make sure sp
1204 is correctly aligned before we start. We always do this even if
1205 it isn't really needed -- it can never hurt things. */
1206 sp &= ~(CORE_ADDR)(2 * DEPRECATED_REGISTER_SIZE - 1);
1207
1208 /* The struct_return pointer occupies the first parameter
1209 passing register. */
1210 if (struct_return)
1211 {
1212 if (arm_debug)
1213 fprintf_unfiltered (gdb_stdlog, "struct return in %s = 0x%s\n",
1214 REGISTER_NAME (argreg), paddr (struct_addr));
1215 regcache_cooked_write_unsigned (regcache, argreg, struct_addr);
1216 argreg++;
1217 }
1218
1219 for (argnum = 0; argnum < nargs; argnum++)
1220 {
1221 int len;
1222 struct type *arg_type;
1223 struct type *target_type;
1224 enum type_code typecode;
1225 char *val;
1226
1227 arg_type = check_typedef (VALUE_TYPE (args[argnum]));
1228 len = TYPE_LENGTH (arg_type);
1229 target_type = TYPE_TARGET_TYPE (arg_type);
1230 typecode = TYPE_CODE (arg_type);
1231 val = VALUE_CONTENTS (args[argnum]);
1232
1233 /* If the argument is a pointer to a function, and it is a
1234 Thumb function, create a LOCAL copy of the value and set
1235 the THUMB bit in it. */
1236 if (TYPE_CODE_PTR == typecode
1237 && target_type != NULL
1238 && TYPE_CODE_FUNC == TYPE_CODE (target_type))
1239 {
1240 CORE_ADDR regval = extract_unsigned_integer (val, len);
1241 if (arm_pc_is_thumb (regval))
1242 {
1243 val = alloca (len);
1244 store_unsigned_integer (val, len, MAKE_THUMB_ADDR (regval));
1245 }
1246 }
1247
1248 /* Copy the argument to general registers or the stack in
1249 register-sized pieces. Large arguments are split between
1250 registers and stack. */
1251 while (len > 0)
1252 {
1253 int partial_len = len < DEPRECATED_REGISTER_SIZE ? len : DEPRECATED_REGISTER_SIZE;
1254
1255 if (argreg <= ARM_LAST_ARG_REGNUM)
1256 {
1257 /* The argument is being passed in a general purpose
1258 register. */
1259 CORE_ADDR regval = extract_unsigned_integer (val, partial_len);
1260 if (arm_debug)
1261 fprintf_unfiltered (gdb_stdlog, "arg %d in %s = 0x%s\n",
1262 argnum, REGISTER_NAME (argreg),
1263 phex (regval, DEPRECATED_REGISTER_SIZE));
1264 regcache_cooked_write_unsigned (regcache, argreg, regval);
1265 argreg++;
1266 }
1267 else
1268 {
1269 /* Push the arguments onto the stack. */
1270 if (arm_debug)
1271 fprintf_unfiltered (gdb_stdlog, "arg %d @ sp + %d\n",
1272 argnum, nstack);
1273 si = push_stack_item (si, val, DEPRECATED_REGISTER_SIZE);
1274 nstack += DEPRECATED_REGISTER_SIZE;
1275 }
1276
1277 len -= partial_len;
1278 val += partial_len;
1279 }
1280 }
1281 /* If we have an odd number of words to push, then decrement the stack
1282 by one word now, so first stack argument will be dword aligned. */
1283 if (nstack & 4)
1284 sp -= 4;
1285
1286 while (si)
1287 {
1288 sp -= si->len;
1289 write_memory (sp, si->data, si->len);
1290 si = pop_stack_item (si);
1291 }
1292
1293 /* Finally, update teh SP register. */
1294 regcache_cooked_write_unsigned (regcache, ARM_SP_REGNUM, sp);
1295
1296 return sp;
1297 }
1298
1299 static void
1300 print_fpu_flags (int flags)
1301 {
1302 if (flags & (1 << 0))
1303 fputs ("IVO ", stdout);
1304 if (flags & (1 << 1))
1305 fputs ("DVZ ", stdout);
1306 if (flags & (1 << 2))
1307 fputs ("OFL ", stdout);
1308 if (flags & (1 << 3))
1309 fputs ("UFL ", stdout);
1310 if (flags & (1 << 4))
1311 fputs ("INX ", stdout);
1312 putchar ('\n');
1313 }
1314
1315 /* Print interesting information about the floating point processor
1316 (if present) or emulator. */
1317 static void
1318 arm_print_float_info (struct gdbarch *gdbarch, struct ui_file *file,
1319 struct frame_info *frame, const char *args)
1320 {
1321 unsigned long status = read_register (ARM_FPS_REGNUM);
1322 int type;
1323
1324 type = (status >> 24) & 127;
1325 printf ("%s FPU type %d\n",
1326 (status & (1 << 31)) ? "Hardware" : "Software",
1327 type);
1328 fputs ("mask: ", stdout);
1329 print_fpu_flags (status >> 16);
1330 fputs ("flags: ", stdout);
1331 print_fpu_flags (status);
1332 }
1333
1334 /* Return the GDB type object for the "standard" data type of data in
1335 register N. */
1336
1337 static struct type *
1338 arm_register_type (struct gdbarch *gdbarch, int regnum)
1339 {
1340 if (regnum >= ARM_F0_REGNUM && regnum < ARM_F0_REGNUM + NUM_FREGS)
1341 {
1342 if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
1343 return builtin_type_arm_ext_big;
1344 else
1345 return builtin_type_arm_ext_littlebyte_bigword;
1346 }
1347 else
1348 return builtin_type_int32;
1349 }
1350
1351 /* Index within `registers' of the first byte of the space for
1352 register N. */
1353
1354 static int
1355 arm_register_byte (int regnum)
1356 {
1357 if (regnum < ARM_F0_REGNUM)
1358 return regnum * INT_REGISTER_SIZE;
1359 else if (regnum < ARM_PS_REGNUM)
1360 return (NUM_GREGS * INT_REGISTER_SIZE
1361 + (regnum - ARM_F0_REGNUM) * FP_REGISTER_SIZE);
1362 else
1363 return (NUM_GREGS * INT_REGISTER_SIZE
1364 + NUM_FREGS * FP_REGISTER_SIZE
1365 + (regnum - ARM_FPS_REGNUM) * STATUS_REGISTER_SIZE);
1366 }
1367
1368 /* Map GDB internal REGNUM onto the Arm simulator register numbers. */
1369 static int
1370 arm_register_sim_regno (int regnum)
1371 {
1372 int reg = regnum;
1373 gdb_assert (reg >= 0 && reg < NUM_REGS);
1374
1375 if (reg < NUM_GREGS)
1376 return SIM_ARM_R0_REGNUM + reg;
1377 reg -= NUM_GREGS;
1378
1379 if (reg < NUM_FREGS)
1380 return SIM_ARM_FP0_REGNUM + reg;
1381 reg -= NUM_FREGS;
1382
1383 if (reg < NUM_SREGS)
1384 return SIM_ARM_FPS_REGNUM + reg;
1385 reg -= NUM_SREGS;
1386
1387 internal_error (__FILE__, __LINE__, "Bad REGNUM %d", regnum);
1388 }
1389
1390 /* NOTE: cagney/2001-08-20: Both convert_from_extended() and
1391 convert_to_extended() use floatformat_arm_ext_littlebyte_bigword.
1392 It is thought that this is is the floating-point register format on
1393 little-endian systems. */
1394
1395 static void
1396 convert_from_extended (const struct floatformat *fmt, const void *ptr,
1397 void *dbl)
1398 {
1399 DOUBLEST d;
1400 if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
1401 floatformat_to_doublest (&floatformat_arm_ext_big, ptr, &d);
1402 else
1403 floatformat_to_doublest (&floatformat_arm_ext_littlebyte_bigword,
1404 ptr, &d);
1405 floatformat_from_doublest (fmt, &d, dbl);
1406 }
1407
1408 static void
1409 convert_to_extended (const struct floatformat *fmt, void *dbl, const void *ptr)
1410 {
1411 DOUBLEST d;
1412 floatformat_to_doublest (fmt, ptr, &d);
1413 if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
1414 floatformat_from_doublest (&floatformat_arm_ext_big, &d, dbl);
1415 else
1416 floatformat_from_doublest (&floatformat_arm_ext_littlebyte_bigword,
1417 &d, dbl);
1418 }
1419
1420 static int
1421 condition_true (unsigned long cond, unsigned long status_reg)
1422 {
1423 if (cond == INST_AL || cond == INST_NV)
1424 return 1;
1425
1426 switch (cond)
1427 {
1428 case INST_EQ:
1429 return ((status_reg & FLAG_Z) != 0);
1430 case INST_NE:
1431 return ((status_reg & FLAG_Z) == 0);
1432 case INST_CS:
1433 return ((status_reg & FLAG_C) != 0);
1434 case INST_CC:
1435 return ((status_reg & FLAG_C) == 0);
1436 case INST_MI:
1437 return ((status_reg & FLAG_N) != 0);
1438 case INST_PL:
1439 return ((status_reg & FLAG_N) == 0);
1440 case INST_VS:
1441 return ((status_reg & FLAG_V) != 0);
1442 case INST_VC:
1443 return ((status_reg & FLAG_V) == 0);
1444 case INST_HI:
1445 return ((status_reg & (FLAG_C | FLAG_Z)) == FLAG_C);
1446 case INST_LS:
1447 return ((status_reg & (FLAG_C | FLAG_Z)) != FLAG_C);
1448 case INST_GE:
1449 return (((status_reg & FLAG_N) == 0) == ((status_reg & FLAG_V) == 0));
1450 case INST_LT:
1451 return (((status_reg & FLAG_N) == 0) != ((status_reg & FLAG_V) == 0));
1452 case INST_GT:
1453 return (((status_reg & FLAG_Z) == 0) &&
1454 (((status_reg & FLAG_N) == 0) == ((status_reg & FLAG_V) == 0)));
1455 case INST_LE:
1456 return (((status_reg & FLAG_Z) != 0) ||
1457 (((status_reg & FLAG_N) == 0) != ((status_reg & FLAG_V) == 0)));
1458 }
1459 return 1;
1460 }
1461
1462 /* Support routines for single stepping. Calculate the next PC value. */
1463 #define submask(x) ((1L << ((x) + 1)) - 1)
1464 #define bit(obj,st) (((obj) >> (st)) & 1)
1465 #define bits(obj,st,fn) (((obj) >> (st)) & submask ((fn) - (st)))
1466 #define sbits(obj,st,fn) \
1467 ((long) (bits(obj,st,fn) | ((long) bit(obj,fn) * ~ submask (fn - st))))
1468 #define BranchDest(addr,instr) \
1469 ((CORE_ADDR) (((long) (addr)) + 8 + (sbits (instr, 0, 23) << 2)))
1470 #define ARM_PC_32 1
1471
1472 static unsigned long
1473 shifted_reg_val (unsigned long inst, int carry, unsigned long pc_val,
1474 unsigned long status_reg)
1475 {
1476 unsigned long res, shift;
1477 int rm = bits (inst, 0, 3);
1478 unsigned long shifttype = bits (inst, 5, 6);
1479
1480 if (bit (inst, 4))
1481 {
1482 int rs = bits (inst, 8, 11);
1483 shift = (rs == 15 ? pc_val + 8 : read_register (rs)) & 0xFF;
1484 }
1485 else
1486 shift = bits (inst, 7, 11);
1487
1488 res = (rm == 15
1489 ? ((pc_val | (ARM_PC_32 ? 0 : status_reg))
1490 + (bit (inst, 4) ? 12 : 8))
1491 : read_register (rm));
1492
1493 switch (shifttype)
1494 {
1495 case 0: /* LSL */
1496 res = shift >= 32 ? 0 : res << shift;
1497 break;
1498
1499 case 1: /* LSR */
1500 res = shift >= 32 ? 0 : res >> shift;
1501 break;
1502
1503 case 2: /* ASR */
1504 if (shift >= 32)
1505 shift = 31;
1506 res = ((res & 0x80000000L)
1507 ? ~((~res) >> shift) : res >> shift);
1508 break;
1509
1510 case 3: /* ROR/RRX */
1511 shift &= 31;
1512 if (shift == 0)
1513 res = (res >> 1) | (carry ? 0x80000000L : 0);
1514 else
1515 res = (res >> shift) | (res << (32 - shift));
1516 break;
1517 }
1518
1519 return res & 0xffffffff;
1520 }
1521
1522 /* Return number of 1-bits in VAL. */
1523
1524 static int
1525 bitcount (unsigned long val)
1526 {
1527 int nbits;
1528 for (nbits = 0; val != 0; nbits++)
1529 val &= val - 1; /* delete rightmost 1-bit in val */
1530 return nbits;
1531 }
1532
1533 CORE_ADDR
1534 thumb_get_next_pc (CORE_ADDR pc)
1535 {
1536 unsigned long pc_val = ((unsigned long) pc) + 4; /* PC after prefetch */
1537 unsigned short inst1 = read_memory_integer (pc, 2);
1538 CORE_ADDR nextpc = pc + 2; /* default is next instruction */
1539 unsigned long offset;
1540
1541 if ((inst1 & 0xff00) == 0xbd00) /* pop {rlist, pc} */
1542 {
1543 CORE_ADDR sp;
1544
1545 /* Fetch the saved PC from the stack. It's stored above
1546 all of the other registers. */
1547 offset = bitcount (bits (inst1, 0, 7)) * DEPRECATED_REGISTER_SIZE;
1548 sp = read_register (ARM_SP_REGNUM);
1549 nextpc = (CORE_ADDR) read_memory_integer (sp + offset, 4);
1550 nextpc = ADDR_BITS_REMOVE (nextpc);
1551 if (nextpc == pc)
1552 error ("Infinite loop detected");
1553 }
1554 else if ((inst1 & 0xf000) == 0xd000) /* conditional branch */
1555 {
1556 unsigned long status = read_register (ARM_PS_REGNUM);
1557 unsigned long cond = bits (inst1, 8, 11);
1558 if (cond != 0x0f && condition_true (cond, status)) /* 0x0f = SWI */
1559 nextpc = pc_val + (sbits (inst1, 0, 7) << 1);
1560 }
1561 else if ((inst1 & 0xf800) == 0xe000) /* unconditional branch */
1562 {
1563 nextpc = pc_val + (sbits (inst1, 0, 10) << 1);
1564 }
1565 else if ((inst1 & 0xf800) == 0xf000) /* long branch with link, and blx */
1566 {
1567 unsigned short inst2 = read_memory_integer (pc + 2, 2);
1568 offset = (sbits (inst1, 0, 10) << 12) + (bits (inst2, 0, 10) << 1);
1569 nextpc = pc_val + offset;
1570 /* For BLX make sure to clear the low bits. */
1571 if (bits (inst2, 11, 12) == 1)
1572 nextpc = nextpc & 0xfffffffc;
1573 }
1574 else if ((inst1 & 0xff00) == 0x4700) /* bx REG, blx REG */
1575 {
1576 if (bits (inst1, 3, 6) == 0x0f)
1577 nextpc = pc_val;
1578 else
1579 nextpc = read_register (bits (inst1, 3, 6));
1580
1581 nextpc = ADDR_BITS_REMOVE (nextpc);
1582 if (nextpc == pc)
1583 error ("Infinite loop detected");
1584 }
1585
1586 return nextpc;
1587 }
1588
1589 CORE_ADDR
1590 arm_get_next_pc (CORE_ADDR pc)
1591 {
1592 unsigned long pc_val;
1593 unsigned long this_instr;
1594 unsigned long status;
1595 CORE_ADDR nextpc;
1596
1597 if (arm_pc_is_thumb (pc))
1598 return thumb_get_next_pc (pc);
1599
1600 pc_val = (unsigned long) pc;
1601 this_instr = read_memory_integer (pc, 4);
1602 status = read_register (ARM_PS_REGNUM);
1603 nextpc = (CORE_ADDR) (pc_val + 4); /* Default case */
1604
1605 if (condition_true (bits (this_instr, 28, 31), status))
1606 {
1607 switch (bits (this_instr, 24, 27))
1608 {
1609 case 0x0:
1610 case 0x1: /* data processing */
1611 case 0x2:
1612 case 0x3:
1613 {
1614 unsigned long operand1, operand2, result = 0;
1615 unsigned long rn;
1616 int c;
1617
1618 if (bits (this_instr, 12, 15) != 15)
1619 break;
1620
1621 if (bits (this_instr, 22, 25) == 0
1622 && bits (this_instr, 4, 7) == 9) /* multiply */
1623 error ("Illegal update to pc in instruction");
1624
1625 /* BX <reg>, BLX <reg> */
1626 if (bits (this_instr, 4, 28) == 0x12fff1
1627 || bits (this_instr, 4, 28) == 0x12fff3)
1628 {
1629 rn = bits (this_instr, 0, 3);
1630 result = (rn == 15) ? pc_val + 8 : read_register (rn);
1631 nextpc = (CORE_ADDR) ADDR_BITS_REMOVE (result);
1632
1633 if (nextpc == pc)
1634 error ("Infinite loop detected");
1635
1636 return nextpc;
1637 }
1638
1639 /* Multiply into PC */
1640 c = (status & FLAG_C) ? 1 : 0;
1641 rn = bits (this_instr, 16, 19);
1642 operand1 = (rn == 15) ? pc_val + 8 : read_register (rn);
1643
1644 if (bit (this_instr, 25))
1645 {
1646 unsigned long immval = bits (this_instr, 0, 7);
1647 unsigned long rotate = 2 * bits (this_instr, 8, 11);
1648 operand2 = ((immval >> rotate) | (immval << (32 - rotate)))
1649 & 0xffffffff;
1650 }
1651 else /* operand 2 is a shifted register */
1652 operand2 = shifted_reg_val (this_instr, c, pc_val, status);
1653
1654 switch (bits (this_instr, 21, 24))
1655 {
1656 case 0x0: /*and */
1657 result = operand1 & operand2;
1658 break;
1659
1660 case 0x1: /*eor */
1661 result = operand1 ^ operand2;
1662 break;
1663
1664 case 0x2: /*sub */
1665 result = operand1 - operand2;
1666 break;
1667
1668 case 0x3: /*rsb */
1669 result = operand2 - operand1;
1670 break;
1671
1672 case 0x4: /*add */
1673 result = operand1 + operand2;
1674 break;
1675
1676 case 0x5: /*adc */
1677 result = operand1 + operand2 + c;
1678 break;
1679
1680 case 0x6: /*sbc */
1681 result = operand1 - operand2 + c;
1682 break;
1683
1684 case 0x7: /*rsc */
1685 result = operand2 - operand1 + c;
1686 break;
1687
1688 case 0x8:
1689 case 0x9:
1690 case 0xa:
1691 case 0xb: /* tst, teq, cmp, cmn */
1692 result = (unsigned long) nextpc;
1693 break;
1694
1695 case 0xc: /*orr */
1696 result = operand1 | operand2;
1697 break;
1698
1699 case 0xd: /*mov */
1700 /* Always step into a function. */
1701 result = operand2;
1702 break;
1703
1704 case 0xe: /*bic */
1705 result = operand1 & ~operand2;
1706 break;
1707
1708 case 0xf: /*mvn */
1709 result = ~operand2;
1710 break;
1711 }
1712 nextpc = (CORE_ADDR) ADDR_BITS_REMOVE (result);
1713
1714 if (nextpc == pc)
1715 error ("Infinite loop detected");
1716 break;
1717 }
1718
1719 case 0x4:
1720 case 0x5: /* data transfer */
1721 case 0x6:
1722 case 0x7:
1723 if (bit (this_instr, 20))
1724 {
1725 /* load */
1726 if (bits (this_instr, 12, 15) == 15)
1727 {
1728 /* rd == pc */
1729 unsigned long rn;
1730 unsigned long base;
1731
1732 if (bit (this_instr, 22))
1733 error ("Illegal update to pc in instruction");
1734
1735 /* byte write to PC */
1736 rn = bits (this_instr, 16, 19);
1737 base = (rn == 15) ? pc_val + 8 : read_register (rn);
1738 if (bit (this_instr, 24))
1739 {
1740 /* pre-indexed */
1741 int c = (status & FLAG_C) ? 1 : 0;
1742 unsigned long offset =
1743 (bit (this_instr, 25)
1744 ? shifted_reg_val (this_instr, c, pc_val, status)
1745 : bits (this_instr, 0, 11));
1746
1747 if (bit (this_instr, 23))
1748 base += offset;
1749 else
1750 base -= offset;
1751 }
1752 nextpc = (CORE_ADDR) read_memory_integer ((CORE_ADDR) base,
1753 4);
1754
1755 nextpc = ADDR_BITS_REMOVE (nextpc);
1756
1757 if (nextpc == pc)
1758 error ("Infinite loop detected");
1759 }
1760 }
1761 break;
1762
1763 case 0x8:
1764 case 0x9: /* block transfer */
1765 if (bit (this_instr, 20))
1766 {
1767 /* LDM */
1768 if (bit (this_instr, 15))
1769 {
1770 /* loading pc */
1771 int offset = 0;
1772
1773 if (bit (this_instr, 23))
1774 {
1775 /* up */
1776 unsigned long reglist = bits (this_instr, 0, 14);
1777 offset = bitcount (reglist) * 4;
1778 if (bit (this_instr, 24)) /* pre */
1779 offset += 4;
1780 }
1781 else if (bit (this_instr, 24))
1782 offset = -4;
1783
1784 {
1785 unsigned long rn_val =
1786 read_register (bits (this_instr, 16, 19));
1787 nextpc =
1788 (CORE_ADDR) read_memory_integer ((CORE_ADDR) (rn_val
1789 + offset),
1790 4);
1791 }
1792 nextpc = ADDR_BITS_REMOVE (nextpc);
1793 if (nextpc == pc)
1794 error ("Infinite loop detected");
1795 }
1796 }
1797 break;
1798
1799 case 0xb: /* branch & link */
1800 case 0xa: /* branch */
1801 {
1802 nextpc = BranchDest (pc, this_instr);
1803
1804 /* BLX */
1805 if (bits (this_instr, 28, 31) == INST_NV)
1806 nextpc |= bit (this_instr, 24) << 1;
1807
1808 nextpc = ADDR_BITS_REMOVE (nextpc);
1809 if (nextpc == pc)
1810 error ("Infinite loop detected");
1811 break;
1812 }
1813
1814 case 0xc:
1815 case 0xd:
1816 case 0xe: /* coproc ops */
1817 case 0xf: /* SWI */
1818 break;
1819
1820 default:
1821 fprintf_filtered (gdb_stderr, "Bad bit-field extraction\n");
1822 return (pc);
1823 }
1824 }
1825
1826 return nextpc;
1827 }
1828
1829 /* single_step() is called just before we want to resume the inferior,
1830 if we want to single-step it but there is no hardware or kernel
1831 single-step support. We find the target of the coming instruction
1832 and breakpoint it.
1833
1834 single_step() is also called just after the inferior stops. If we
1835 had set up a simulated single-step, we undo our damage. */
1836
1837 static void
1838 arm_software_single_step (enum target_signal sig, int insert_bpt)
1839 {
1840 static int next_pc; /* State between setting and unsetting. */
1841 static char break_mem[BREAKPOINT_MAX]; /* Temporary storage for mem@bpt */
1842
1843 if (insert_bpt)
1844 {
1845 next_pc = arm_get_next_pc (read_register (ARM_PC_REGNUM));
1846 target_insert_breakpoint (next_pc, break_mem);
1847 }
1848 else
1849 target_remove_breakpoint (next_pc, break_mem);
1850 }
1851
1852 #include "bfd-in2.h"
1853 #include "libcoff.h"
1854
1855 static int
1856 gdb_print_insn_arm (bfd_vma memaddr, disassemble_info *info)
1857 {
1858 if (arm_pc_is_thumb (memaddr))
1859 {
1860 static asymbol *asym;
1861 static combined_entry_type ce;
1862 static struct coff_symbol_struct csym;
1863 static struct bfd fake_bfd;
1864 static bfd_target fake_target;
1865
1866 if (csym.native == NULL)
1867 {
1868 /* Create a fake symbol vector containing a Thumb symbol.
1869 This is solely so that the code in print_insn_little_arm()
1870 and print_insn_big_arm() in opcodes/arm-dis.c will detect
1871 the presence of a Thumb symbol and switch to decoding
1872 Thumb instructions. */
1873
1874 fake_target.flavour = bfd_target_coff_flavour;
1875 fake_bfd.xvec = &fake_target;
1876 ce.u.syment.n_sclass = C_THUMBEXTFUNC;
1877 csym.native = &ce;
1878 csym.symbol.the_bfd = &fake_bfd;
1879 csym.symbol.name = "fake";
1880 asym = (asymbol *) & csym;
1881 }
1882
1883 memaddr = UNMAKE_THUMB_ADDR (memaddr);
1884 info->symbols = &asym;
1885 }
1886 else
1887 info->symbols = NULL;
1888
1889 if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
1890 return print_insn_big_arm (memaddr, info);
1891 else
1892 return print_insn_little_arm (memaddr, info);
1893 }
1894
1895 /* The following define instruction sequences that will cause ARM
1896 cpu's to take an undefined instruction trap. These are used to
1897 signal a breakpoint to GDB.
1898
1899 The newer ARMv4T cpu's are capable of operating in ARM or Thumb
1900 modes. A different instruction is required for each mode. The ARM
1901 cpu's can also be big or little endian. Thus four different
1902 instructions are needed to support all cases.
1903
1904 Note: ARMv4 defines several new instructions that will take the
1905 undefined instruction trap. ARM7TDMI is nominally ARMv4T, but does
1906 not in fact add the new instructions. The new undefined
1907 instructions in ARMv4 are all instructions that had no defined
1908 behaviour in earlier chips. There is no guarantee that they will
1909 raise an exception, but may be treated as NOP's. In practice, it
1910 may only safe to rely on instructions matching:
1911
1912 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
1913 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
1914 C C C C 0 1 1 x x x x x x x x x x x x x x x x x x x x 1 x x x x
1915
1916 Even this may only true if the condition predicate is true. The
1917 following use a condition predicate of ALWAYS so it is always TRUE.
1918
1919 There are other ways of forcing a breakpoint. GNU/Linux, RISC iX,
1920 and NetBSD all use a software interrupt rather than an undefined
1921 instruction to force a trap. This can be handled by by the
1922 abi-specific code during establishment of the gdbarch vector. */
1923
1924
1925 /* NOTE rearnsha 2002-02-18: for now we allow a non-multi-arch gdb to
1926 override these definitions. */
1927 #ifndef ARM_LE_BREAKPOINT
1928 #define ARM_LE_BREAKPOINT {0xFE,0xDE,0xFF,0xE7}
1929 #endif
1930 #ifndef ARM_BE_BREAKPOINT
1931 #define ARM_BE_BREAKPOINT {0xE7,0xFF,0xDE,0xFE}
1932 #endif
1933 #ifndef THUMB_LE_BREAKPOINT
1934 #define THUMB_LE_BREAKPOINT {0xfe,0xdf}
1935 #endif
1936 #ifndef THUMB_BE_BREAKPOINT
1937 #define THUMB_BE_BREAKPOINT {0xdf,0xfe}
1938 #endif
1939
1940 static const char arm_default_arm_le_breakpoint[] = ARM_LE_BREAKPOINT;
1941 static const char arm_default_arm_be_breakpoint[] = ARM_BE_BREAKPOINT;
1942 static const char arm_default_thumb_le_breakpoint[] = THUMB_LE_BREAKPOINT;
1943 static const char arm_default_thumb_be_breakpoint[] = THUMB_BE_BREAKPOINT;
1944
1945 /* Determine the type and size of breakpoint to insert at PCPTR. Uses
1946 the program counter value to determine whether a 16-bit or 32-bit
1947 breakpoint should be used. It returns a pointer to a string of
1948 bytes that encode a breakpoint instruction, stores the length of
1949 the string to *lenptr, and adjusts the program counter (if
1950 necessary) to point to the actual memory location where the
1951 breakpoint should be inserted. */
1952
1953 /* XXX ??? from old tm-arm.h: if we're using RDP, then we're inserting
1954 breakpoints and storing their handles instread of what was in
1955 memory. It is nice that this is the same size as a handle -
1956 otherwise remote-rdp will have to change. */
1957
1958 static const unsigned char *
1959 arm_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
1960 {
1961 struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
1962
1963 if (arm_pc_is_thumb (*pcptr) || arm_pc_is_thumb_dummy (*pcptr))
1964 {
1965 *pcptr = UNMAKE_THUMB_ADDR (*pcptr);
1966 *lenptr = tdep->thumb_breakpoint_size;
1967 return tdep->thumb_breakpoint;
1968 }
1969 else
1970 {
1971 *lenptr = tdep->arm_breakpoint_size;
1972 return tdep->arm_breakpoint;
1973 }
1974 }
1975
1976 /* Extract from an array REGBUF containing the (raw) register state a
1977 function return value of type TYPE, and copy that, in virtual
1978 format, into VALBUF. */
1979
1980 static void
1981 arm_extract_return_value (struct type *type,
1982 struct regcache *regs,
1983 void *dst)
1984 {
1985 bfd_byte *valbuf = dst;
1986
1987 if (TYPE_CODE_FLT == TYPE_CODE (type))
1988 {
1989 switch (arm_get_fp_model (current_gdbarch))
1990 {
1991 case ARM_FLOAT_FPA:
1992 {
1993 /* The value is in register F0 in internal format. We need to
1994 extract the raw value and then convert it to the desired
1995 internal type. */
1996 bfd_byte tmpbuf[FP_REGISTER_SIZE];
1997
1998 regcache_cooked_read (regs, ARM_F0_REGNUM, tmpbuf);
1999 convert_from_extended (floatformat_from_type (type), tmpbuf,
2000 valbuf);
2001 }
2002 break;
2003
2004 case ARM_FLOAT_SOFT_FPA:
2005 case ARM_FLOAT_SOFT_VFP:
2006 regcache_cooked_read (regs, ARM_A1_REGNUM, valbuf);
2007 if (TYPE_LENGTH (type) > 4)
2008 regcache_cooked_read (regs, ARM_A1_REGNUM + 1,
2009 valbuf + INT_REGISTER_SIZE);
2010 break;
2011
2012 default:
2013 internal_error
2014 (__FILE__, __LINE__,
2015 "arm_extract_return_value: Floating point model not supported");
2016 break;
2017 }
2018 }
2019 else if (TYPE_CODE (type) == TYPE_CODE_INT
2020 || TYPE_CODE (type) == TYPE_CODE_CHAR
2021 || TYPE_CODE (type) == TYPE_CODE_BOOL
2022 || TYPE_CODE (type) == TYPE_CODE_PTR
2023 || TYPE_CODE (type) == TYPE_CODE_REF
2024 || TYPE_CODE (type) == TYPE_CODE_ENUM)
2025 {
2026 /* If the the type is a plain integer, then the access is
2027 straight-forward. Otherwise we have to play around a bit more. */
2028 int len = TYPE_LENGTH (type);
2029 int regno = ARM_A1_REGNUM;
2030 ULONGEST tmp;
2031
2032 while (len > 0)
2033 {
2034 /* By using store_unsigned_integer we avoid having to do
2035 anything special for small big-endian values. */
2036 regcache_cooked_read_unsigned (regs, regno++, &tmp);
2037 store_unsigned_integer (valbuf,
2038 (len > INT_REGISTER_SIZE
2039 ? INT_REGISTER_SIZE : len),
2040 tmp);
2041 len -= INT_REGISTER_SIZE;
2042 valbuf += INT_REGISTER_SIZE;
2043 }
2044 }
2045 else
2046 {
2047 /* For a structure or union the behaviour is as if the value had
2048 been stored to word-aligned memory and then loaded into
2049 registers with 32-bit load instruction(s). */
2050 int len = TYPE_LENGTH (type);
2051 int regno = ARM_A1_REGNUM;
2052 bfd_byte tmpbuf[INT_REGISTER_SIZE];
2053
2054 while (len > 0)
2055 {
2056 regcache_cooked_read (regs, regno++, tmpbuf);
2057 memcpy (valbuf, tmpbuf,
2058 len > INT_REGISTER_SIZE ? INT_REGISTER_SIZE : len);
2059 len -= INT_REGISTER_SIZE;
2060 valbuf += INT_REGISTER_SIZE;
2061 }
2062 }
2063 }
2064
2065 /* Extract from an array REGBUF containing the (raw) register state
2066 the address in which a function should return its structure value. */
2067
2068 static CORE_ADDR
2069 arm_extract_struct_value_address (struct regcache *regcache)
2070 {
2071 ULONGEST ret;
2072
2073 regcache_cooked_read_unsigned (regcache, ARM_A1_REGNUM, &ret);
2074 return ret;
2075 }
2076
2077 /* Will a function return an aggregate type in memory or in a
2078 register? Return 0 if an aggregate type can be returned in a
2079 register, 1 if it must be returned in memory. */
2080
2081 static int
2082 arm_use_struct_convention (int gcc_p, struct type *type)
2083 {
2084 int nRc;
2085 enum type_code code;
2086
2087 CHECK_TYPEDEF (type);
2088
2089 /* In the ARM ABI, "integer" like aggregate types are returned in
2090 registers. For an aggregate type to be integer like, its size
2091 must be less than or equal to DEPRECATED_REGISTER_SIZE and the
2092 offset of each addressable subfield must be zero. Note that bit
2093 fields are not addressable, and all addressable subfields of
2094 unions always start at offset zero.
2095
2096 This function is based on the behaviour of GCC 2.95.1.
2097 See: gcc/arm.c: arm_return_in_memory() for details.
2098
2099 Note: All versions of GCC before GCC 2.95.2 do not set up the
2100 parameters correctly for a function returning the following
2101 structure: struct { float f;}; This should be returned in memory,
2102 not a register. Richard Earnshaw sent me a patch, but I do not
2103 know of any way to detect if a function like the above has been
2104 compiled with the correct calling convention. */
2105
2106 /* All aggregate types that won't fit in a register must be returned
2107 in memory. */
2108 if (TYPE_LENGTH (type) > DEPRECATED_REGISTER_SIZE)
2109 {
2110 return 1;
2111 }
2112
2113 /* The only aggregate types that can be returned in a register are
2114 structs and unions. Arrays must be returned in memory. */
2115 code = TYPE_CODE (type);
2116 if ((TYPE_CODE_STRUCT != code) && (TYPE_CODE_UNION != code))
2117 {
2118 return 1;
2119 }
2120
2121 /* Assume all other aggregate types can be returned in a register.
2122 Run a check for structures, unions and arrays. */
2123 nRc = 0;
2124
2125 if ((TYPE_CODE_STRUCT == code) || (TYPE_CODE_UNION == code))
2126 {
2127 int i;
2128 /* Need to check if this struct/union is "integer" like. For
2129 this to be true, its size must be less than or equal to
2130 DEPRECATED_REGISTER_SIZE and the offset of each addressable
2131 subfield must be zero. Note that bit fields are not
2132 addressable, and unions always start at offset zero. If any
2133 of the subfields is a floating point type, the struct/union
2134 cannot be an integer type. */
2135
2136 /* For each field in the object, check:
2137 1) Is it FP? --> yes, nRc = 1;
2138 2) Is it addressable (bitpos != 0) and
2139 not packed (bitsize == 0)?
2140 --> yes, nRc = 1
2141 */
2142
2143 for (i = 0; i < TYPE_NFIELDS (type); i++)
2144 {
2145 enum type_code field_type_code;
2146 field_type_code = TYPE_CODE (check_typedef (TYPE_FIELD_TYPE (type, i)));
2147
2148 /* Is it a floating point type field? */
2149 if (field_type_code == TYPE_CODE_FLT)
2150 {
2151 nRc = 1;
2152 break;
2153 }
2154
2155 /* If bitpos != 0, then we have to care about it. */
2156 if (TYPE_FIELD_BITPOS (type, i) != 0)
2157 {
2158 /* Bitfields are not addressable. If the field bitsize is
2159 zero, then the field is not packed. Hence it cannot be
2160 a bitfield or any other packed type. */
2161 if (TYPE_FIELD_BITSIZE (type, i) == 0)
2162 {
2163 nRc = 1;
2164 break;
2165 }
2166 }
2167 }
2168 }
2169
2170 return nRc;
2171 }
2172
2173 /* Write into appropriate registers a function return value of type
2174 TYPE, given in virtual format. */
2175
2176 static void
2177 arm_store_return_value (struct type *type, struct regcache *regs,
2178 const void *src)
2179 {
2180 const bfd_byte *valbuf = src;
2181
2182 if (TYPE_CODE (type) == TYPE_CODE_FLT)
2183 {
2184 char buf[MAX_REGISTER_SIZE];
2185
2186 switch (arm_get_fp_model (current_gdbarch))
2187 {
2188 case ARM_FLOAT_FPA:
2189
2190 convert_to_extended (floatformat_from_type (type), buf, valbuf);
2191 regcache_cooked_write (regs, ARM_F0_REGNUM, buf);
2192 break;
2193
2194 case ARM_FLOAT_SOFT_FPA:
2195 case ARM_FLOAT_SOFT_VFP:
2196 regcache_cooked_write (regs, ARM_A1_REGNUM, valbuf);
2197 if (TYPE_LENGTH (type) > 4)
2198 regcache_cooked_write (regs, ARM_A1_REGNUM + 1,
2199 valbuf + INT_REGISTER_SIZE);
2200 break;
2201
2202 default:
2203 internal_error
2204 (__FILE__, __LINE__,
2205 "arm_store_return_value: Floating point model not supported");
2206 break;
2207 }
2208 }
2209 else if (TYPE_CODE (type) == TYPE_CODE_INT
2210 || TYPE_CODE (type) == TYPE_CODE_CHAR
2211 || TYPE_CODE (type) == TYPE_CODE_BOOL
2212 || TYPE_CODE (type) == TYPE_CODE_PTR
2213 || TYPE_CODE (type) == TYPE_CODE_REF
2214 || TYPE_CODE (type) == TYPE_CODE_ENUM)
2215 {
2216 if (TYPE_LENGTH (type) <= 4)
2217 {
2218 /* Values of one word or less are zero/sign-extended and
2219 returned in r0. */
2220 bfd_byte tmpbuf[INT_REGISTER_SIZE];
2221 LONGEST val = unpack_long (type, valbuf);
2222
2223 store_signed_integer (tmpbuf, INT_REGISTER_SIZE, val);
2224 regcache_cooked_write (regs, ARM_A1_REGNUM, tmpbuf);
2225 }
2226 else
2227 {
2228 /* Integral values greater than one word are stored in consecutive
2229 registers starting with r0. This will always be a multiple of
2230 the regiser size. */
2231 int len = TYPE_LENGTH (type);
2232 int regno = ARM_A1_REGNUM;
2233
2234 while (len > 0)
2235 {
2236 regcache_cooked_write (regs, regno++, valbuf);
2237 len -= INT_REGISTER_SIZE;
2238 valbuf += INT_REGISTER_SIZE;
2239 }
2240 }
2241 }
2242 else
2243 {
2244 /* For a structure or union the behaviour is as if the value had
2245 been stored to word-aligned memory and then loaded into
2246 registers with 32-bit load instruction(s). */
2247 int len = TYPE_LENGTH (type);
2248 int regno = ARM_A1_REGNUM;
2249 bfd_byte tmpbuf[INT_REGISTER_SIZE];
2250
2251 while (len > 0)
2252 {
2253 memcpy (tmpbuf, valbuf,
2254 len > INT_REGISTER_SIZE ? INT_REGISTER_SIZE : len);
2255 regcache_cooked_write (regs, regno++, tmpbuf);
2256 len -= INT_REGISTER_SIZE;
2257 valbuf += INT_REGISTER_SIZE;
2258 }
2259 }
2260 }
2261
2262 static int
2263 arm_get_longjmp_target (CORE_ADDR *pc)
2264 {
2265 CORE_ADDR jb_addr;
2266 char buf[INT_REGISTER_SIZE];
2267 struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
2268
2269 jb_addr = read_register (ARM_A1_REGNUM);
2270
2271 if (target_read_memory (jb_addr + tdep->jb_pc * tdep->jb_elt_size, buf,
2272 INT_REGISTER_SIZE))
2273 return 0;
2274
2275 *pc = extract_unsigned_integer (buf, INT_REGISTER_SIZE);
2276 return 1;
2277 }
2278
2279 /* Return non-zero if the PC is inside a thumb call thunk. */
2280
2281 int
2282 arm_in_call_stub (CORE_ADDR pc, char *name)
2283 {
2284 CORE_ADDR start_addr;
2285
2286 /* Find the starting address of the function containing the PC. If
2287 the caller didn't give us a name, look it up at the same time. */
2288 if (0 == find_pc_partial_function (pc, name ? NULL : &name,
2289 &start_addr, NULL))
2290 return 0;
2291
2292 return strncmp (name, "_call_via_r", 11) == 0;
2293 }
2294
2295 /* If PC is in a Thumb call or return stub, return the address of the
2296 target PC, which is in a register. The thunk functions are called
2297 _called_via_xx, where x is the register name. The possible names
2298 are r0-r9, sl, fp, ip, sp, and lr. */
2299
2300 CORE_ADDR
2301 arm_skip_stub (CORE_ADDR pc)
2302 {
2303 char *name;
2304 CORE_ADDR start_addr;
2305
2306 /* Find the starting address and name of the function containing the PC. */
2307 if (find_pc_partial_function (pc, &name, &start_addr, NULL) == 0)
2308 return 0;
2309
2310 /* Call thunks always start with "_call_via_". */
2311 if (strncmp (name, "_call_via_", 10) == 0)
2312 {
2313 /* Use the name suffix to determine which register contains the
2314 target PC. */
2315 static char *table[15] =
2316 {"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
2317 "r8", "r9", "sl", "fp", "ip", "sp", "lr"
2318 };
2319 int regno;
2320
2321 for (regno = 0; regno <= 14; regno++)
2322 if (strcmp (&name[10], table[regno]) == 0)
2323 return read_register (regno);
2324 }
2325
2326 return 0; /* not a stub */
2327 }
2328
2329 static void
2330 set_arm_command (char *args, int from_tty)
2331 {
2332 printf_unfiltered ("\"set arm\" must be followed by an apporpriate subcommand.\n");
2333 help_list (setarmcmdlist, "set arm ", all_commands, gdb_stdout);
2334 }
2335
2336 static void
2337 show_arm_command (char *args, int from_tty)
2338 {
2339 cmd_show_list (showarmcmdlist, from_tty, "");
2340 }
2341
2342 enum arm_float_model
2343 arm_get_fp_model (struct gdbarch *gdbarch)
2344 {
2345 if (arm_fp_model == ARM_FLOAT_AUTO)
2346 return gdbarch_tdep (gdbarch)->fp_model;
2347
2348 return arm_fp_model;
2349 }
2350
2351 static void
2352 arm_set_fp (struct gdbarch *gdbarch)
2353 {
2354 enum arm_float_model fp_model = arm_get_fp_model (gdbarch);
2355
2356 if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_LITTLE
2357 && (fp_model == ARM_FLOAT_SOFT_FPA || fp_model == ARM_FLOAT_FPA))
2358 {
2359 set_gdbarch_double_format (gdbarch,
2360 &floatformat_ieee_double_littlebyte_bigword);
2361 set_gdbarch_long_double_format
2362 (gdbarch, &floatformat_ieee_double_littlebyte_bigword);
2363 }
2364 else
2365 {
2366 set_gdbarch_double_format (gdbarch, &floatformat_ieee_double_little);
2367 set_gdbarch_long_double_format (gdbarch,
2368 &floatformat_ieee_double_little);
2369 }
2370 }
2371
2372 static void
2373 set_fp_model_sfunc (char *args, int from_tty,
2374 struct cmd_list_element *c)
2375 {
2376 enum arm_float_model fp_model;
2377
2378 for (fp_model = ARM_FLOAT_AUTO; fp_model != ARM_FLOAT_LAST; fp_model++)
2379 if (strcmp (current_fp_model, fp_model_strings[fp_model]) == 0)
2380 {
2381 arm_fp_model = fp_model;
2382 break;
2383 }
2384
2385 if (fp_model == ARM_FLOAT_LAST)
2386 internal_error (__FILE__, __LINE__, "Invalid fp model accepted: %s.",
2387 current_fp_model);
2388
2389 if (gdbarch_bfd_arch_info (current_gdbarch)->arch == bfd_arch_arm)
2390 arm_set_fp (current_gdbarch);
2391 }
2392
2393 static void
2394 show_fp_model (char *args, int from_tty,
2395 struct cmd_list_element *c)
2396 {
2397 struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
2398
2399 if (arm_fp_model == ARM_FLOAT_AUTO
2400 && gdbarch_bfd_arch_info (current_gdbarch)->arch == bfd_arch_arm)
2401 printf_filtered (" - the default for the current ABI is \"%s\".\n",
2402 fp_model_strings[tdep->fp_model]);
2403 }
2404
2405 /* If the user changes the register disassembly style used for info
2406 register and other commands, we have to also switch the style used
2407 in opcodes for disassembly output. This function is run in the "set
2408 arm disassembly" command, and does that. */
2409
2410 static void
2411 set_disassembly_style_sfunc (char *args, int from_tty,
2412 struct cmd_list_element *c)
2413 {
2414 set_disassembly_style ();
2415 }
2416 \f
2417 /* Return the ARM register name corresponding to register I. */
2418 static const char *
2419 arm_register_name (int i)
2420 {
2421 return arm_register_names[i];
2422 }
2423
2424 static void
2425 set_disassembly_style (void)
2426 {
2427 const char *setname, *setdesc, **regnames;
2428 int numregs, j;
2429
2430 /* Find the style that the user wants in the opcodes table. */
2431 int current = 0;
2432 numregs = get_arm_regnames (current, &setname, &setdesc, &regnames);
2433 while ((disassembly_style != setname)
2434 && (current < num_disassembly_options))
2435 get_arm_regnames (++current, &setname, &setdesc, &regnames);
2436 current_option = current;
2437
2438 /* Fill our copy. */
2439 for (j = 0; j < numregs; j++)
2440 arm_register_names[j] = (char *) regnames[j];
2441
2442 /* Adjust case. */
2443 if (isupper (*regnames[ARM_PC_REGNUM]))
2444 {
2445 arm_register_names[ARM_FPS_REGNUM] = "FPS";
2446 arm_register_names[ARM_PS_REGNUM] = "CPSR";
2447 }
2448 else
2449 {
2450 arm_register_names[ARM_FPS_REGNUM] = "fps";
2451 arm_register_names[ARM_PS_REGNUM] = "cpsr";
2452 }
2453
2454 /* Synchronize the disassembler. */
2455 set_arm_regname_option (current);
2456 }
2457
2458 /* arm_othernames implements the "othernames" command. This is deprecated
2459 by the "set arm disassembly" command. */
2460
2461 static void
2462 arm_othernames (char *names, int n)
2463 {
2464 /* Circle through the various flavors. */
2465 current_option = (current_option + 1) % num_disassembly_options;
2466
2467 disassembly_style = valid_disassembly_styles[current_option];
2468 set_disassembly_style ();
2469 }
2470
2471 /* Test whether the coff symbol specific value corresponds to a Thumb
2472 function. */
2473
2474 static int
2475 coff_sym_is_thumb (int val)
2476 {
2477 return (val == C_THUMBEXT ||
2478 val == C_THUMBSTAT ||
2479 val == C_THUMBEXTFUNC ||
2480 val == C_THUMBSTATFUNC ||
2481 val == C_THUMBLABEL);
2482 }
2483
2484 /* arm_coff_make_msymbol_special()
2485 arm_elf_make_msymbol_special()
2486
2487 These functions test whether the COFF or ELF symbol corresponds to
2488 an address in thumb code, and set a "special" bit in a minimal
2489 symbol to indicate that it does. */
2490
2491 static void
2492 arm_elf_make_msymbol_special(asymbol *sym, struct minimal_symbol *msym)
2493 {
2494 /* Thumb symbols are of type STT_LOPROC, (synonymous with
2495 STT_ARM_TFUNC). */
2496 if (ELF_ST_TYPE (((elf_symbol_type *)sym)->internal_elf_sym.st_info)
2497 == STT_LOPROC)
2498 MSYMBOL_SET_SPECIAL (msym);
2499 }
2500
2501 static void
2502 arm_coff_make_msymbol_special(int val, struct minimal_symbol *msym)
2503 {
2504 if (coff_sym_is_thumb (val))
2505 MSYMBOL_SET_SPECIAL (msym);
2506 }
2507
2508 static void
2509 arm_write_pc (CORE_ADDR pc, ptid_t ptid)
2510 {
2511 write_register_pid (ARM_PC_REGNUM, pc, ptid);
2512
2513 /* If necessary, set the T bit. */
2514 if (arm_apcs_32)
2515 {
2516 CORE_ADDR val = read_register_pid (ARM_PS_REGNUM, ptid);
2517 if (arm_pc_is_thumb (pc))
2518 write_register_pid (ARM_PS_REGNUM, val | 0x20, ptid);
2519 else
2520 write_register_pid (ARM_PS_REGNUM, val & ~(CORE_ADDR) 0x20, ptid);
2521 }
2522 }
2523 \f
2524 static enum gdb_osabi
2525 arm_elf_osabi_sniffer (bfd *abfd)
2526 {
2527 unsigned int elfosabi, eflags;
2528 enum gdb_osabi osabi = GDB_OSABI_UNKNOWN;
2529
2530 elfosabi = elf_elfheader (abfd)->e_ident[EI_OSABI];
2531
2532 switch (elfosabi)
2533 {
2534 case ELFOSABI_NONE:
2535 /* When elfosabi is ELFOSABI_NONE (0), then the ELF structures in the
2536 file are conforming to the base specification for that machine
2537 (there are no OS-specific extensions). In order to determine the
2538 real OS in use we must look for OS notes that have been added. */
2539 bfd_map_over_sections (abfd,
2540 generic_elf_osabi_sniff_abi_tag_sections,
2541 &osabi);
2542 if (osabi == GDB_OSABI_UNKNOWN)
2543 {
2544 /* Existing ARM tools don't set this field, so look at the EI_FLAGS
2545 field for more information. */
2546 eflags = EF_ARM_EABI_VERSION(elf_elfheader(abfd)->e_flags);
2547 switch (eflags)
2548 {
2549 case EF_ARM_EABI_VER1:
2550 osabi = GDB_OSABI_ARM_EABI_V1;
2551 break;
2552
2553 case EF_ARM_EABI_VER2:
2554 osabi = GDB_OSABI_ARM_EABI_V2;
2555 break;
2556
2557 case EF_ARM_EABI_UNKNOWN:
2558 /* Assume GNU tools. */
2559 osabi = GDB_OSABI_ARM_APCS;
2560 break;
2561
2562 default:
2563 internal_error (__FILE__, __LINE__,
2564 "arm_elf_osabi_sniffer: Unknown ARM EABI "
2565 "version 0x%x", eflags);
2566 }
2567 }
2568 break;
2569
2570 case ELFOSABI_ARM:
2571 /* GNU tools use this value. Check note sections in this case,
2572 as well. */
2573 bfd_map_over_sections (abfd,
2574 generic_elf_osabi_sniff_abi_tag_sections,
2575 &osabi);
2576 if (osabi == GDB_OSABI_UNKNOWN)
2577 {
2578 /* Assume APCS ABI. */
2579 osabi = GDB_OSABI_ARM_APCS;
2580 }
2581 break;
2582
2583 case ELFOSABI_FREEBSD:
2584 osabi = GDB_OSABI_FREEBSD_ELF;
2585 break;
2586
2587 case ELFOSABI_NETBSD:
2588 osabi = GDB_OSABI_NETBSD_ELF;
2589 break;
2590
2591 case ELFOSABI_LINUX:
2592 osabi = GDB_OSABI_LINUX;
2593 break;
2594 }
2595
2596 return osabi;
2597 }
2598
2599 \f
2600 /* Initialize the current architecture based on INFO. If possible,
2601 re-use an architecture from ARCHES, which is a list of
2602 architectures already created during this debugging session.
2603
2604 Called e.g. at program startup, when reading a core file, and when
2605 reading a binary file. */
2606
2607 static struct gdbarch *
2608 arm_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
2609 {
2610 struct gdbarch_tdep *tdep;
2611 struct gdbarch *gdbarch;
2612
2613 /* Try to deterimine the ABI of the object we are loading. */
2614
2615 if (info.abfd != NULL && info.osabi == GDB_OSABI_UNKNOWN)
2616 {
2617 switch (bfd_get_flavour (info.abfd))
2618 {
2619 case bfd_target_aout_flavour:
2620 /* Assume it's an old APCS-style ABI. */
2621 info.osabi = GDB_OSABI_ARM_APCS;
2622 break;
2623
2624 case bfd_target_coff_flavour:
2625 /* Assume it's an old APCS-style ABI. */
2626 /* XXX WinCE? */
2627 info.osabi = GDB_OSABI_ARM_APCS;
2628 break;
2629
2630 default:
2631 /* Leave it as "unknown". */
2632 break;
2633 }
2634 }
2635
2636 /* If there is already a candidate, use it. */
2637 arches = gdbarch_list_lookup_by_info (arches, &info);
2638 if (arches != NULL)
2639 return arches->gdbarch;
2640
2641 tdep = xmalloc (sizeof (struct gdbarch_tdep));
2642 gdbarch = gdbarch_alloc (&info, tdep);
2643
2644 /* We used to default to FPA for generic ARM, but almost nobody uses that
2645 now, and we now provide a way for the user to force the model. So
2646 default to the most useful variant. */
2647 tdep->fp_model = ARM_FLOAT_SOFT_FPA;
2648
2649 /* Breakpoints. */
2650 switch (info.byte_order)
2651 {
2652 case BFD_ENDIAN_BIG:
2653 tdep->arm_breakpoint = arm_default_arm_be_breakpoint;
2654 tdep->arm_breakpoint_size = sizeof (arm_default_arm_be_breakpoint);
2655 tdep->thumb_breakpoint = arm_default_thumb_be_breakpoint;
2656 tdep->thumb_breakpoint_size = sizeof (arm_default_thumb_be_breakpoint);
2657
2658 break;
2659
2660 case BFD_ENDIAN_LITTLE:
2661 tdep->arm_breakpoint = arm_default_arm_le_breakpoint;
2662 tdep->arm_breakpoint_size = sizeof (arm_default_arm_le_breakpoint);
2663 tdep->thumb_breakpoint = arm_default_thumb_le_breakpoint;
2664 tdep->thumb_breakpoint_size = sizeof (arm_default_thumb_le_breakpoint);
2665
2666 break;
2667
2668 default:
2669 internal_error (__FILE__, __LINE__,
2670 "arm_gdbarch_init: bad byte order for float format");
2671 }
2672
2673 /* On ARM targets char defaults to unsigned. */
2674 set_gdbarch_char_signed (gdbarch, 0);
2675
2676 /* This should be low enough for everything. */
2677 tdep->lowest_pc = 0x20;
2678 tdep->jb_pc = -1; /* Longjump support not enabled by default. */
2679
2680 set_gdbarch_push_dummy_call (gdbarch, arm_push_dummy_call);
2681
2682 set_gdbarch_write_pc (gdbarch, arm_write_pc);
2683
2684 /* Frame handling. */
2685 set_gdbarch_unwind_dummy_id (gdbarch, arm_unwind_dummy_id);
2686 set_gdbarch_unwind_pc (gdbarch, arm_unwind_pc);
2687 set_gdbarch_unwind_sp (gdbarch, arm_unwind_sp);
2688
2689 frame_base_set_default (gdbarch, &arm_normal_base);
2690
2691 /* Address manipulation. */
2692 set_gdbarch_smash_text_address (gdbarch, arm_smash_text_address);
2693 set_gdbarch_addr_bits_remove (gdbarch, arm_addr_bits_remove);
2694
2695 /* Advance PC across function entry code. */
2696 set_gdbarch_skip_prologue (gdbarch, arm_skip_prologue);
2697
2698 /* Get the PC when a frame might not be available. */
2699 set_gdbarch_deprecated_saved_pc_after_call (gdbarch, arm_saved_pc_after_call);
2700
2701 /* The stack grows downward. */
2702 set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
2703
2704 /* Breakpoint manipulation. */
2705 set_gdbarch_breakpoint_from_pc (gdbarch, arm_breakpoint_from_pc);
2706
2707 /* Information about registers, etc. */
2708 set_gdbarch_print_float_info (gdbarch, arm_print_float_info);
2709 set_gdbarch_deprecated_fp_regnum (gdbarch, ARM_FP_REGNUM); /* ??? */
2710 set_gdbarch_sp_regnum (gdbarch, ARM_SP_REGNUM);
2711 set_gdbarch_pc_regnum (gdbarch, ARM_PC_REGNUM);
2712 set_gdbarch_deprecated_register_byte (gdbarch, arm_register_byte);
2713 set_gdbarch_num_regs (gdbarch, NUM_GREGS + NUM_FREGS + NUM_SREGS);
2714 set_gdbarch_register_type (gdbarch, arm_register_type);
2715
2716 /* Internal <-> external register number maps. */
2717 set_gdbarch_register_sim_regno (gdbarch, arm_register_sim_regno);
2718
2719 /* Integer registers are 4 bytes. */
2720 set_gdbarch_deprecated_register_size (gdbarch, 4);
2721 set_gdbarch_register_name (gdbarch, arm_register_name);
2722
2723 /* Returning results. */
2724 set_gdbarch_extract_return_value (gdbarch, arm_extract_return_value);
2725 set_gdbarch_store_return_value (gdbarch, arm_store_return_value);
2726 set_gdbarch_deprecated_use_struct_convention (gdbarch, arm_use_struct_convention);
2727 set_gdbarch_deprecated_extract_struct_value_address (gdbarch, arm_extract_struct_value_address);
2728
2729 /* Single stepping. */
2730 /* XXX For an RDI target we should ask the target if it can single-step. */
2731 set_gdbarch_software_single_step (gdbarch, arm_software_single_step);
2732
2733 /* Disassembly. */
2734 set_gdbarch_print_insn (gdbarch, gdb_print_insn_arm);
2735
2736 /* Minsymbol frobbing. */
2737 set_gdbarch_elf_make_msymbol_special (gdbarch, arm_elf_make_msymbol_special);
2738 set_gdbarch_coff_make_msymbol_special (gdbarch,
2739 arm_coff_make_msymbol_special);
2740
2741 /* Hook in the ABI-specific overrides, if they have been registered. */
2742 gdbarch_init_osabi (info, gdbarch);
2743
2744 /* Add some default predicates. */
2745 frame_unwind_append_sniffer (gdbarch, arm_sigtramp_unwind_sniffer);
2746 frame_unwind_append_sniffer (gdbarch, arm_prologue_unwind_sniffer);
2747
2748 /* Now we have tuned the configuration, set a few final things,
2749 based on what the OS ABI has told us. */
2750
2751 if (tdep->jb_pc >= 0)
2752 set_gdbarch_get_longjmp_target (gdbarch, arm_get_longjmp_target);
2753
2754 /* Floating point sizes and format. */
2755 switch (info.byte_order)
2756 {
2757 case BFD_ENDIAN_BIG:
2758 set_gdbarch_float_format (gdbarch, &floatformat_ieee_single_big);
2759 set_gdbarch_double_format (gdbarch, &floatformat_ieee_double_big);
2760 set_gdbarch_long_double_format (gdbarch, &floatformat_ieee_double_big);
2761
2762 break;
2763
2764 case BFD_ENDIAN_LITTLE:
2765 set_gdbarch_float_format (gdbarch, &floatformat_ieee_single_little);
2766 arm_set_fp (gdbarch);
2767 break;
2768
2769 default:
2770 internal_error (__FILE__, __LINE__,
2771 "arm_gdbarch_init: bad byte order for float format");
2772 }
2773
2774 return gdbarch;
2775 }
2776
2777 static void
2778 arm_dump_tdep (struct gdbarch *current_gdbarch, struct ui_file *file)
2779 {
2780 struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
2781
2782 if (tdep == NULL)
2783 return;
2784
2785 fprintf_unfiltered (file, "arm_dump_tdep: Lowest pc = 0x%lx",
2786 (unsigned long) tdep->lowest_pc);
2787 }
2788
2789 static void
2790 arm_init_abi_eabi_v1 (struct gdbarch_info info,
2791 struct gdbarch *gdbarch)
2792 {
2793 /* Place-holder. */
2794 }
2795
2796 static void
2797 arm_init_abi_eabi_v2 (struct gdbarch_info info,
2798 struct gdbarch *gdbarch)
2799 {
2800 /* Place-holder. */
2801 }
2802
2803 static void
2804 arm_init_abi_apcs (struct gdbarch_info info,
2805 struct gdbarch *gdbarch)
2806 {
2807 /* Place-holder. */
2808 }
2809
2810 extern initialize_file_ftype _initialize_arm_tdep; /* -Wmissing-prototypes */
2811
2812 void
2813 _initialize_arm_tdep (void)
2814 {
2815 struct ui_file *stb;
2816 long length;
2817 struct cmd_list_element *new_set, *new_show;
2818 const char *setname;
2819 const char *setdesc;
2820 const char **regnames;
2821 int numregs, i, j;
2822 static char *helptext;
2823
2824 gdbarch_register (bfd_arch_arm, arm_gdbarch_init, arm_dump_tdep);
2825
2826 /* Register an ELF OS ABI sniffer for ARM binaries. */
2827 gdbarch_register_osabi_sniffer (bfd_arch_arm,
2828 bfd_target_elf_flavour,
2829 arm_elf_osabi_sniffer);
2830
2831 /* Register some ABI variants for embedded systems. */
2832 gdbarch_register_osabi (bfd_arch_arm, 0, GDB_OSABI_ARM_EABI_V1,
2833 arm_init_abi_eabi_v1);
2834 gdbarch_register_osabi (bfd_arch_arm, 0, GDB_OSABI_ARM_EABI_V2,
2835 arm_init_abi_eabi_v2);
2836 gdbarch_register_osabi (bfd_arch_arm, 0, GDB_OSABI_ARM_APCS,
2837 arm_init_abi_apcs);
2838
2839 /* Get the number of possible sets of register names defined in opcodes. */
2840 num_disassembly_options = get_arm_regname_num_options ();
2841
2842 /* Add root prefix command for all "set arm"/"show arm" commands. */
2843 add_prefix_cmd ("arm", no_class, set_arm_command,
2844 "Various ARM-specific commands.",
2845 &setarmcmdlist, "set arm ", 0, &setlist);
2846
2847 add_prefix_cmd ("arm", no_class, show_arm_command,
2848 "Various ARM-specific commands.",
2849 &showarmcmdlist, "show arm ", 0, &showlist);
2850
2851 /* Sync the opcode insn printer with our register viewer. */
2852 parse_arm_disassembler_option ("reg-names-std");
2853
2854 /* Begin creating the help text. */
2855 stb = mem_fileopen ();
2856 fprintf_unfiltered (stb, "Set the disassembly style.\n"
2857 "The valid values are:\n");
2858
2859 /* Initialize the array that will be passed to add_set_enum_cmd(). */
2860 valid_disassembly_styles
2861 = xmalloc ((num_disassembly_options + 1) * sizeof (char *));
2862 for (i = 0; i < num_disassembly_options; i++)
2863 {
2864 numregs = get_arm_regnames (i, &setname, &setdesc, &regnames);
2865 valid_disassembly_styles[i] = setname;
2866 fprintf_unfiltered (stb, "%s - %s\n", setname,
2867 setdesc);
2868 /* Copy the default names (if found) and synchronize disassembler. */
2869 if (!strcmp (setname, "std"))
2870 {
2871 disassembly_style = setname;
2872 current_option = i;
2873 for (j = 0; j < numregs; j++)
2874 arm_register_names[j] = (char *) regnames[j];
2875 set_arm_regname_option (i);
2876 }
2877 }
2878 /* Mark the end of valid options. */
2879 valid_disassembly_styles[num_disassembly_options] = NULL;
2880
2881 /* Finish the creation of the help text. */
2882 fprintf_unfiltered (stb, "The default is \"std\".");
2883 helptext = ui_file_xstrdup (stb, &length);
2884 ui_file_delete (stb);
2885
2886 /* Add the deprecated disassembly-flavor command. */
2887 new_set = add_set_enum_cmd ("disassembly-flavor", no_class,
2888 valid_disassembly_styles,
2889 &disassembly_style,
2890 helptext,
2891 &setlist);
2892 set_cmd_sfunc (new_set, set_disassembly_style_sfunc);
2893 deprecate_cmd (new_set, "set arm disassembly");
2894 deprecate_cmd (deprecated_add_show_from_set (new_set, &showlist),
2895 "show arm disassembly");
2896
2897 /* And now add the new interface. */
2898 new_set = add_set_enum_cmd ("disassembler", no_class,
2899 valid_disassembly_styles, &disassembly_style,
2900 helptext, &setarmcmdlist);
2901
2902 set_cmd_sfunc (new_set, set_disassembly_style_sfunc);
2903 deprecated_add_show_from_set (new_set, &showarmcmdlist);
2904
2905 add_setshow_boolean_cmd ("apcs32", no_class, &arm_apcs_32, "\
2906 Set usage of ARM 32-bit mode.", "\
2907 Show usage of ARM 32-bit mode.", "\
2908 When off, a 26-bit PC will be used.\n\
2909 When off, a 26-bit PC will be used.", "\
2910 Usage of ARM 32-bit mode is %s.",
2911 NULL, NULL,
2912 &setarmcmdlist, &showarmcmdlist);
2913
2914 /* Add a command to allow the user to force the FPU model. */
2915 new_set = add_set_enum_cmd
2916 ("fpu", no_class, fp_model_strings, &current_fp_model,
2917 "Set the floating point type.\n"
2918 "auto - Determine the FP typefrom the OS-ABI.\n"
2919 "softfpa - Software FP, mixed-endian doubles on little-endian ARMs.\n"
2920 "fpa - FPA co-processor (GCC compiled).\n"
2921 "softvfp - Software FP with pure-endian doubles.\n"
2922 "vfp - VFP co-processor.",
2923 &setarmcmdlist);
2924 set_cmd_sfunc (new_set, set_fp_model_sfunc);
2925 set_cmd_sfunc (deprecated_add_show_from_set (new_set, &showarmcmdlist),
2926 show_fp_model);
2927
2928 /* Add the deprecated "othernames" command. */
2929 deprecate_cmd (add_com ("othernames", class_obscure, arm_othernames,
2930 "Switch to the next set of register names."),
2931 "set arm disassembly");
2932
2933 /* Debugging flag. */
2934 add_setshow_boolean_cmd ("arm", class_maintenance, &arm_debug, "\
2935 Set ARM debugging.", "\
2936 Show ARM debugging.", "\
2937 When on, arm-specific debugging is enabled.", "\
2938 ARM debugging is %s.",
2939 NULL, NULL,
2940 &setdebuglist, &showdebuglist);
2941 }
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