1 /* Target-dependent code for the MIPS architecture, for GDB, the GNU Debugger.
2 Copyright 1988, 1989, 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
3 Contributed by Alessandro Forin(af@cs.cmu.edu) at CMU
4 and by Per Bothner(bothner@cs.wisc.edu) at U.Wisconsin.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
33 #define VM_MIN_ADDRESS (unsigned)0x400000
35 /* Some MIPS boards don't support floating point, so we permit the
36 user to turn it off. */
39 /* Heuristic_proc_start may hunt through the text section for a long
40 time across a 2400 baud serial line. Allows the user to limit this
42 static unsigned int heuristic_fence_post
= 0;
44 #define PROC_LOW_ADDR(proc) ((proc)->pdr.adr) /* least address */
45 #define PROC_HIGH_ADDR(proc) ((proc)->pdr.iline) /* upper address bound */
46 #define PROC_FRAME_OFFSET(proc) ((proc)->pdr.frameoffset)
47 #define PROC_FRAME_REG(proc) ((proc)->pdr.framereg)
48 #define PROC_REG_MASK(proc) ((proc)->pdr.regmask)
49 #define PROC_FREG_MASK(proc) ((proc)->pdr.fregmask)
50 #define PROC_REG_OFFSET(proc) ((proc)->pdr.regoffset)
51 #define PROC_FREG_OFFSET(proc) ((proc)->pdr.fregoffset)
52 #define PROC_PC_REG(proc) ((proc)->pdr.pcreg)
53 #define PROC_SYMBOL(proc) (*(struct symbol**)&(proc)->pdr.isym)
54 #define _PROC_MAGIC_ 0x0F0F0F0F
55 #define PROC_DESC_IS_DUMMY(proc) ((proc)->pdr.isym == _PROC_MAGIC_)
56 #define SET_PROC_DESC_IS_DUMMY(proc) ((proc)->pdr.isym = _PROC_MAGIC_)
58 struct linked_proc_info
60 struct mips_extra_func_info info
;
61 struct linked_proc_info
*next
;
62 } *linked_proc_desc_table
= NULL
;
65 #define READ_FRAME_REG(fi, regno) read_next_frame_reg((fi)->next, regno)
68 read_next_frame_reg(fi
, regno
)
72 /* If it is the frame for sigtramp we have a complete sigcontext
73 immediately below the frame and we get the saved registers from there.
74 If the stack layout for sigtramp changes we might have to change these
75 constants and the companion fixup_sigtramp in mipsread.c */
77 #define SIGFRAME_BASE 0x12c /* sizeof(sigcontext) */
78 #define SIGFRAME_PC_OFF (-SIGFRAME_BASE + 2 * 4)
79 #define SIGFRAME_REGSAVE_OFF (-SIGFRAME_BASE + 3 * 4)
81 for (; fi
; fi
= fi
->next
)
82 if (in_sigtramp(fi
->pc
, 0)) {
84 if (regno
== PC_REGNUM
) offset
= SIGFRAME_PC_OFF
;
85 else if (regno
< 32) offset
= SIGFRAME_REGSAVE_OFF
+ regno
* 4;
87 return read_memory_integer(fi
->frame
+ offset
, 4);
89 else if (regno
== SP_REGNUM
) return fi
->frame
;
90 else if (fi
->saved_regs
->regs
[regno
])
91 return read_memory_integer(fi
->saved_regs
->regs
[regno
], 4);
92 return read_register(regno
);
96 mips_frame_saved_pc(frame
)
99 mips_extra_func_info_t proc_desc
= frame
->proc_desc
;
100 int pcreg
= proc_desc
? PROC_PC_REG(proc_desc
) : RA_REGNUM
;
102 if (proc_desc
&& PROC_DESC_IS_DUMMY(proc_desc
))
103 return read_memory_integer(frame
->frame
- 4, 4);
105 return read_next_frame_reg(frame
, pcreg
);
108 static struct mips_extra_func_info temp_proc_desc
;
109 static struct frame_saved_regs temp_saved_regs
;
111 /* This fencepost looks highly suspicious to me. Removing it also
112 seems suspicious as it could affect remote debugging across serial
116 heuristic_proc_start(pc
)
119 CORE_ADDR start_pc
= pc
;
120 CORE_ADDR fence
= start_pc
- heuristic_fence_post
;
122 if (start_pc
== 0) return 0;
124 if (heuristic_fence_post
== UINT_MAX
125 || fence
< VM_MIN_ADDRESS
)
126 fence
= VM_MIN_ADDRESS
;
128 /* search back for previous return */
129 for (start_pc
-= 4; ; start_pc
-= 4)
130 if (start_pc
< fence
)
132 /* It's not clear to me why we reach this point when
133 stop_soon_quietly, but with this test, at least we
134 don't print out warnings for every child forked (eg, on
135 decstation). 22apr93 rich@cygnus.com. */
136 if (!stop_soon_quietly
)
138 if (fence
== VM_MIN_ADDRESS
)
139 warning("Hit beginning of text section without finding");
141 warning("Hit heuristic-fence-post without finding");
143 warning("enclosing function for pc 0x%x", pc
);
148 else if (ABOUT_TO_RETURN(start_pc
))
151 start_pc
+= 8; /* skip return, and its delay slot */
153 /* skip nops (usually 1) 0 - is this */
154 while (start_pc
< pc
&& read_memory_integer (start_pc
, 4) == 0)
160 static mips_extra_func_info_t
161 heuristic_proc_desc(start_pc
, limit_pc
, next_frame
)
162 CORE_ADDR start_pc
, limit_pc
;
165 CORE_ADDR sp
= next_frame
? next_frame
->frame
: read_register (SP_REGNUM
);
168 int has_frame_reg
= 0;
169 int reg30
; /* Value of $r30. Used by gcc for frame-pointer */
170 unsigned long reg_mask
= 0;
172 if (start_pc
== 0) return NULL
;
173 bzero(&temp_proc_desc
, sizeof(temp_proc_desc
));
174 bzero(&temp_saved_regs
, sizeof(struct frame_saved_regs
));
175 PROC_LOW_ADDR(&temp_proc_desc
) = start_pc
;
177 if (start_pc
+ 200 < limit_pc
) limit_pc
= start_pc
+ 200;
180 for (cur_pc
= start_pc
; cur_pc
< limit_pc
; cur_pc
+= 4) {
184 status
= read_memory_nobpt (cur_pc
, (char *)&word
, 4);
185 if (status
) memory_error (status
, cur_pc
);
186 SWAP_TARGET_AND_HOST (&word
, sizeof (word
));
187 if ((word
& 0xFFFF0000) == 0x27bd0000) /* addiu $sp,$sp,-i */
188 frame_size
+= (-word
) & 0xFFFF;
189 else if ((word
& 0xFFFF0000) == 0x23bd0000) /* addu $sp,$sp,-i */
190 frame_size
+= (-word
) & 0xFFFF;
191 else if ((word
& 0xFFE00000) == 0xafa00000) { /* sw reg,offset($sp) */
192 int reg
= (word
& 0x001F0000) >> 16;
193 reg_mask
|= 1 << reg
;
194 temp_saved_regs
.regs
[reg
] = sp
+ (short)word
;
196 else if ((word
& 0xFFFF0000) == 0x27be0000) { /* addiu $30,$sp,size */
197 if ((unsigned short)word
!= frame_size
)
198 reg30
= sp
+ (unsigned short)word
;
199 else if (!has_frame_reg
) {
202 reg30
= read_next_frame_reg(next_frame
, 30);
203 alloca_adjust
= reg30
- (sp
+ (unsigned short)word
);
204 if (alloca_adjust
> 0) {
205 /* FP > SP + frame_size. This may be because
206 /* of an alloca or somethings similar.
207 * Fix sp to "pre-alloca" value, and try again.
214 else if ((word
& 0xFFE00000) == 0xafc00000) { /* sw reg,offset($30) */
215 int reg
= (word
& 0x001F0000) >> 16;
216 reg_mask
|= 1 << reg
;
217 temp_saved_regs
.regs
[reg
] = reg30
+ (short)word
;
221 PROC_FRAME_REG(&temp_proc_desc
) = 30;
222 PROC_FRAME_OFFSET(&temp_proc_desc
) = 0;
225 PROC_FRAME_REG(&temp_proc_desc
) = SP_REGNUM
;
226 PROC_FRAME_OFFSET(&temp_proc_desc
) = frame_size
;
228 PROC_REG_MASK(&temp_proc_desc
) = reg_mask
;
229 PROC_PC_REG(&temp_proc_desc
) = RA_REGNUM
;
230 return &temp_proc_desc
;
233 static mips_extra_func_info_t
234 find_proc_desc(pc
, next_frame
)
238 mips_extra_func_info_t proc_desc
;
239 struct block
*b
= block_for_pc(pc
);
241 b
? lookup_symbol(MIPS_EFI_SYMBOL_NAME
, b
, LABEL_NAMESPACE
, 0, NULL
) : NULL
;
245 /* IF this is the topmost frame AND
246 * (this proc does not have debugging information OR
247 * the PC is in the procedure prologue)
248 * THEN create a "heuristic" proc_desc (by analyzing
249 * the actual code) to replace the "official" proc_desc.
251 proc_desc
= (mips_extra_func_info_t
)SYMBOL_VALUE(sym
);
252 if (next_frame
== NULL
) {
253 struct symtab_and_line val
;
254 struct symbol
*proc_symbol
=
255 PROC_DESC_IS_DUMMY(proc_desc
) ? 0 : PROC_SYMBOL(proc_desc
);
258 val
= find_pc_line (BLOCK_START
259 (SYMBOL_BLOCK_VALUE(proc_symbol
)),
261 val
.pc
= val
.end
? val
.end
: pc
;
263 if (!proc_symbol
|| pc
< val
.pc
) {
264 mips_extra_func_info_t found_heuristic
=
265 heuristic_proc_desc(PROC_LOW_ADDR(proc_desc
),
267 if (found_heuristic
) proc_desc
= found_heuristic
;
273 /* Is linked_proc_desc_table really necessary? It only seems to be used
274 by procedure call dummys. However, the procedures being called ought
275 to have their own proc_descs, and even if they don't,
276 heuristic_proc_desc knows how to create them! */
278 register struct linked_proc_info
*link
;
279 for (link
= linked_proc_desc_table
; link
; link
= link
->next
)
280 if (PROC_LOW_ADDR(&link
->info
) <= pc
281 && PROC_HIGH_ADDR(&link
->info
) > pc
)
284 heuristic_proc_desc(heuristic_proc_start(pc
), pc
, next_frame
);
289 mips_extra_func_info_t cached_proc_desc
;
292 mips_frame_chain(frame
)
295 mips_extra_func_info_t proc_desc
;
296 CORE_ADDR saved_pc
= FRAME_SAVED_PC(frame
);
298 if (saved_pc
== 0 || inside_entry_file (saved_pc
))
301 proc_desc
= find_proc_desc(saved_pc
, frame
);
305 cached_proc_desc
= proc_desc
;
306 return read_next_frame_reg(frame
, PROC_FRAME_REG(proc_desc
))
307 + PROC_FRAME_OFFSET(proc_desc
);
311 init_extra_frame_info(fci
)
312 struct frame_info
*fci
;
314 extern struct obstack frame_cache_obstack
;
315 /* Use proc_desc calculated in frame_chain */
316 mips_extra_func_info_t proc_desc
= fci
->next
? cached_proc_desc
:
317 find_proc_desc(fci
->pc
, fci
->next
);
319 fci
->saved_regs
= (struct frame_saved_regs
*)
320 obstack_alloc (&frame_cache_obstack
, sizeof(struct frame_saved_regs
));
321 bzero(fci
->saved_regs
, sizeof(struct frame_saved_regs
));
323 proc_desc
== &temp_proc_desc
? 0 : proc_desc
;
327 CORE_ADDR reg_position
;
329 /* r0 bit means kernel trap */
330 int kernel_trap
= PROC_REG_MASK(proc_desc
) & 1;
332 /* Fixup frame-pointer - only needed for top frame */
333 /* This may not be quite right, if proc has a real frame register */
334 if (fci
->pc
== PROC_LOW_ADDR(proc_desc
))
335 fci
->frame
= read_register (SP_REGNUM
);
337 fci
->frame
= READ_FRAME_REG(fci
, PROC_FRAME_REG(proc_desc
))
338 + PROC_FRAME_OFFSET(proc_desc
);
340 if (proc_desc
== &temp_proc_desc
)
341 *fci
->saved_regs
= temp_saved_regs
;
344 /* find which general-purpose registers were saved */
345 reg_position
= fci
->frame
+ PROC_REG_OFFSET(proc_desc
);
346 mask
= kernel_trap
? 0xFFFFFFFF : PROC_REG_MASK(proc_desc
);
347 for (ireg
= 31; mask
; --ireg
, mask
<<= 1)
348 if (mask
& 0x80000000)
350 fci
->saved_regs
->regs
[ireg
] = reg_position
;
353 /* find which floating-point registers were saved */
354 reg_position
= fci
->frame
+ PROC_FREG_OFFSET(proc_desc
);
355 /* The freg_offset points to where the first *double* register is saved.
356 * So skip to the high-order word. */
358 mask
= kernel_trap
? 0xFFFFFFFF : PROC_FREG_MASK(proc_desc
);
359 for (ireg
= 31; mask
; --ireg
, mask
<<= 1)
360 if (mask
& 0x80000000)
362 fci
->saved_regs
->regs
[FP0_REGNUM
+ireg
] = reg_position
;
367 /* hack: if argument regs are saved, guess these contain args */
368 if ((PROC_REG_MASK(proc_desc
) & 0xF0) == 0) fci
->num_args
= -1;
369 else if ((PROC_REG_MASK(proc_desc
) & 0x80) == 0) fci
->num_args
= 4;
370 else if ((PROC_REG_MASK(proc_desc
) & 0x40) == 0) fci
->num_args
= 3;
371 else if ((PROC_REG_MASK(proc_desc
) & 0x20) == 0) fci
->num_args
= 2;
372 else if ((PROC_REG_MASK(proc_desc
) & 0x10) == 0) fci
->num_args
= 1;
374 fci
->saved_regs
->regs
[PC_REGNUM
] = fci
->saved_regs
->regs
[RA_REGNUM
];
378 /* MIPS stack frames are almost impenetrable. When execution stops,
379 we basically have to look at symbol information for the function
380 that we stopped in, which tells us *which* register (if any) is
381 the base of the frame pointer, and what offset from that register
382 the frame itself is at.
384 This presents a problem when trying to examine a stack in memory
385 (that isn't executing at the moment), using the "frame" command. We
386 don't have a PC, nor do we have any registers except SP.
388 This routine takes two arguments, SP and PC, and tries to make the
389 cached frames look as if these two arguments defined a frame on the
390 cache. This allows the rest of info frame to extract the important
391 arguments without difficulty. */
394 setup_arbitrary_frame (argc
, argv
)
399 error ("MIPS frame specifications require two arguments: sp and pc");
401 return create_new_frame (argv
[0], argv
[1]);
406 mips_push_arguments(nargs
, args
, sp
, struct_return
, struct_addr
)
411 CORE_ADDR struct_addr
;
415 int accumulate_size
= struct_return
? 4 : 0;
416 struct mips_arg
{ char *contents
; int len
; int offset
; };
417 struct mips_arg
*mips_args
=
418 (struct mips_arg
*)alloca(nargs
* sizeof(struct mips_arg
));
419 register struct mips_arg
*m_arg
;
420 for (i
= 0, m_arg
= mips_args
; i
< nargs
; i
++, m_arg
++) {
421 extern value
value_arg_coerce();
422 value arg
= value_arg_coerce (args
[i
]);
423 m_arg
->len
= TYPE_LENGTH (VALUE_TYPE (arg
));
424 /* This entire mips-specific routine is because doubles must be aligned
425 * on 8-byte boundaries. It still isn't quite right, because MIPS decided
426 * to align 'struct {int a, b}' on 4-byte boundaries (even though this
427 * breaks their varargs implementation...). A correct solution
428 * requires an simulation of gcc's 'alignof' (and use of 'alignof'
429 * in stdarg.h/varargs.h).
431 if (m_arg
->len
> 4) accumulate_size
= (accumulate_size
+ 7) & -8;
432 m_arg
->offset
= accumulate_size
;
433 accumulate_size
= (accumulate_size
+ m_arg
->len
+ 3) & -4;
434 m_arg
->contents
= VALUE_CONTENTS(arg
);
436 accumulate_size
= (accumulate_size
+ 7) & (-8);
437 if (accumulate_size
< 16) accumulate_size
= 16;
438 sp
-= accumulate_size
;
439 for (i
= nargs
; m_arg
--, --i
>= 0; )
440 write_memory(sp
+ m_arg
->offset
, m_arg
->contents
, m_arg
->len
);
443 write_memory(sp
, (char *)&buf
, sizeof(CORE_ADDR
));
448 /* MASK(i,j) == (1<<i) + (1<<(i+1)) + ... + (1<<j)). Assume i<=j<31. */
449 #define MASK(i,j) ((1 << (j)+1)-1 ^ (1 << (i))-1)
452 mips_push_dummy_frame()
455 struct linked_proc_info
*link
= (struct linked_proc_info
*)
456 xmalloc(sizeof(struct linked_proc_info
));
457 mips_extra_func_info_t proc_desc
= &link
->info
;
458 CORE_ADDR sp
= read_register (SP_REGNUM
);
459 CORE_ADDR save_address
;
460 REGISTER_TYPE buffer
;
461 link
->next
= linked_proc_desc_table
;
462 linked_proc_desc_table
= link
;
463 #define PUSH_FP_REGNUM 16 /* must be a register preserved across calls */
464 #define GEN_REG_SAVE_MASK MASK(1,16)|MASK(24,28)|(1<<31)
465 #define GEN_REG_SAVE_COUNT 22
466 #define FLOAT_REG_SAVE_MASK MASK(0,19)
467 #define FLOAT_REG_SAVE_COUNT 20
468 #define SPECIAL_REG_SAVE_COUNT 4
470 * The registers we must save are all those not preserved across
471 * procedure calls. Dest_Reg (see tm-mips.h) must also be saved.
472 * In addition, we must save the PC, and PUSH_FP_REGNUM.
473 * (Ideally, we should also save MDLO/-HI and FP Control/Status reg.)
475 * Dummy frame layout:
478 * Saved MMHI, MMLO, FPC_CSR
483 * Saved D18 (i.e. F19, F18)
485 * Saved D0 (i.e. F1, F0)
486 * CALL_DUMMY (subroutine stub; see tm-mips.h)
487 * Parameter build area (not yet implemented)
490 PROC_REG_MASK(proc_desc
) = GEN_REG_SAVE_MASK
;
491 PROC_FREG_MASK(proc_desc
) = mips_fpu
? FLOAT_REG_SAVE_MASK
: 0;
492 PROC_REG_OFFSET(proc_desc
) = /* offset of (Saved R31) from FP */
493 -sizeof(long) - 4 * SPECIAL_REG_SAVE_COUNT
;
494 PROC_FREG_OFFSET(proc_desc
) = /* offset of (Saved D18) from FP */
495 -sizeof(double) - 4 * (SPECIAL_REG_SAVE_COUNT
+ GEN_REG_SAVE_COUNT
);
496 /* save general registers */
497 save_address
= sp
+ PROC_REG_OFFSET(proc_desc
);
498 for (ireg
= 32; --ireg
>= 0; )
499 if (PROC_REG_MASK(proc_desc
) & (1 << ireg
))
501 buffer
= read_register (ireg
);
502 write_memory (save_address
, (char *)&buffer
, sizeof(REGISTER_TYPE
));
505 /* save floating-points registers starting with high order word */
506 save_address
= sp
+ PROC_FREG_OFFSET(proc_desc
) + 4;
507 for (ireg
= 32; --ireg
>= 0; )
508 if (PROC_FREG_MASK(proc_desc
) & (1 << ireg
))
510 buffer
= read_register (ireg
+ FP0_REGNUM
);
511 write_memory (save_address
, (char *)&buffer
, 4);
514 write_register (PUSH_FP_REGNUM
, sp
);
515 PROC_FRAME_REG(proc_desc
) = PUSH_FP_REGNUM
;
516 PROC_FRAME_OFFSET(proc_desc
) = 0;
517 buffer
= read_register (PC_REGNUM
);
518 write_memory (sp
- 4, (char *)&buffer
, sizeof(REGISTER_TYPE
));
519 buffer
= read_register (HI_REGNUM
);
520 write_memory (sp
- 8, (char *)&buffer
, sizeof(REGISTER_TYPE
));
521 buffer
= read_register (LO_REGNUM
);
522 write_memory (sp
- 12, (char *)&buffer
, sizeof(REGISTER_TYPE
));
523 buffer
= read_register (mips_fpu
? FCRCS_REGNUM
: ZERO_REGNUM
);
524 write_memory (sp
- 16, (char *)&buffer
, sizeof(REGISTER_TYPE
));
525 sp
-= 4 * (GEN_REG_SAVE_COUNT
526 + (mips_fpu
? FLOAT_REG_SAVE_COUNT
: 0)
527 + SPECIAL_REG_SAVE_COUNT
);
528 write_register (SP_REGNUM
, sp
);
529 PROC_LOW_ADDR(proc_desc
) = sp
- CALL_DUMMY_SIZE
+ CALL_DUMMY_START_OFFSET
;
530 PROC_HIGH_ADDR(proc_desc
) = sp
;
531 SET_PROC_DESC_IS_DUMMY(proc_desc
);
532 PROC_PC_REG(proc_desc
) = RA_REGNUM
;
539 FRAME frame
= get_current_frame ();
540 CORE_ADDR new_sp
= frame
->frame
;
542 mips_extra_func_info_t proc_desc
= frame
->proc_desc
;
544 write_register (PC_REGNUM
, FRAME_SAVED_PC(frame
));
547 for (regnum
= 32; --regnum
>= 0; )
548 if (PROC_REG_MASK(proc_desc
) & (1 << regnum
))
549 write_register (regnum
,
550 read_memory_integer (frame
->saved_regs
->regs
[regnum
],
552 for (regnum
= 32; --regnum
>= 0; )
553 if (PROC_FREG_MASK(proc_desc
) & (1 << regnum
))
554 write_register (regnum
+ FP0_REGNUM
,
555 read_memory_integer (frame
->saved_regs
->regs
[regnum
+ FP0_REGNUM
], 4));
557 write_register (SP_REGNUM
, new_sp
);
558 flush_cached_frames ();
559 /* We let mips_init_extra_frame_info figure out the frame pointer */
560 set_current_frame (create_new_frame (0, read_pc ()));
562 if (PROC_DESC_IS_DUMMY(proc_desc
))
564 struct linked_proc_info
*pi_ptr
, *prev_ptr
;
566 for (pi_ptr
= linked_proc_desc_table
, prev_ptr
= NULL
;
568 prev_ptr
= pi_ptr
, pi_ptr
= pi_ptr
->next
)
570 if (&pi_ptr
->info
== proc_desc
)
575 error ("Can't locate dummy extra frame info\n");
577 if (prev_ptr
!= NULL
)
578 prev_ptr
->next
= pi_ptr
->next
;
580 linked_proc_desc_table
= pi_ptr
->next
;
584 write_register (HI_REGNUM
, read_memory_integer(new_sp
- 8, 4));
585 write_register (LO_REGNUM
, read_memory_integer(new_sp
- 12, 4));
587 write_register (FCRCS_REGNUM
, read_memory_integer(new_sp
- 16, 4));
592 mips_print_register (regnum
, all
)
595 unsigned char raw_buffer
[MAX_REGISTER_RAW_SIZE
];
598 /* Get the data in raw format. */
599 if (read_relative_register_raw_bytes (regnum
, raw_buffer
))
601 printf_filtered ("%s: [Invalid]", reg_names
[regnum
]);
605 /* If an even floating pointer register, also print as double. */
606 if (regnum
>= FP0_REGNUM
&& regnum
< FP0_REGNUM
+32
607 && !((regnum
-FP0_REGNUM
) & 1)) {
608 char dbuffer
[MAX_REGISTER_RAW_SIZE
];
610 read_relative_register_raw_bytes (regnum
, dbuffer
);
611 read_relative_register_raw_bytes (regnum
+1, dbuffer
+4);
612 #ifdef REGISTER_CONVERT_TO_TYPE
613 REGISTER_CONVERT_TO_TYPE(regnum
, builtin_type_double
, dbuffer
);
615 printf_filtered ("(d%d: ", regnum
-FP0_REGNUM
);
616 val_print (builtin_type_double
, dbuffer
, 0,
617 stdout
, 0, 1, 0, Val_pretty_default
);
618 printf_filtered ("); ");
620 fputs_filtered (reg_names
[regnum
], stdout
);
621 #ifndef NUMERIC_REG_NAMES
623 printf_filtered ("(r%d): ", regnum
);
626 printf_filtered (": ");
628 /* If virtual format is floating, print it that way. */
629 if (TYPE_CODE (REGISTER_VIRTUAL_TYPE (regnum
)) == TYPE_CODE_FLT
630 && ! INVALID_FLOAT (raw_buffer
, REGISTER_VIRTUAL_SIZE(regnum
))) {
631 val_print (REGISTER_VIRTUAL_TYPE (regnum
), raw_buffer
, 0,
632 stdout
, 0, 1, 0, Val_pretty_default
);
634 /* Else print as integer in hex. */
639 bcopy (raw_buffer
, &val
, sizeof (long));
640 SWAP_TARGET_AND_HOST ((char *)&val
, sizeof (long));
642 printf_filtered ("0");
644 printf_filtered (local_hex_format(), val
);
646 printf_filtered ("%s=%d", local_hex_string(val
), val
);
650 /* Replacement for generic do_registers_info. */
652 mips_do_registers_info (regnum
, fpregs
)
657 mips_print_register (regnum
, 0);
658 printf_filtered ("\n");
661 for (regnum
= 0; regnum
< NUM_REGS
; ) {
662 if ((!fpregs
) && regnum
>= FP0_REGNUM
&& regnum
<= FCRIR_REGNUM
) {
666 mips_print_register (regnum
, 1);
668 if ((regnum
& 3) == 0 || regnum
== NUM_REGS
)
669 printf_filtered (";\n");
671 printf_filtered ("; ");
675 /* Return number of args passed to a frame. described by FIP.
676 Can return -1, meaning no way to tell. */
679 mips_frame_num_args(fip
)
683 struct chain_info_t
*p
;
685 p
= mips_find_cached_frame(FRAME_FP(fip
));
687 return p
->the_info
.numargs
;
693 /* Bad floats: Returns 0 if P points to a valid IEEE floating point number,
694 1 if P points to a denormalized number or a NaN. LEN says whether this is
695 a single-precision or double-precision float */
696 #define SINGLE_EXP_BITS 8
697 #define DOUBLE_EXP_BITS 11
706 exponent
= exponent
<< 1 >> (32 - SINGLE_EXP_BITS
- 1);
707 return ((exponent
== -1) || (exponent
== 0 && ((*p
<< 1) != 0)));
711 #if TARGET_BYTE_ORDER == BIG_ENDIAN
716 exponent
= exponent
<< 1 >> (32 - DOUBLE_EXP_BITS
- 1);
717 return ((exponent
== -1) || (! exponent
&& *p
* *(p
+1)));
722 /* To skip prologues, I use this predicate. Returns either PC
723 itself if the code at PC does not look like a function prologue;
724 otherwise returns an address that (if we're lucky) follows
728 mips_skip_prologue(pc
)
735 int seen_sp_adjust
= 0;
737 /* Skip the typical prologue instructions. These are the stack adjustment
738 instruction and the instructions that save registers on the stack
739 or in the gcc frame. */
740 for (offset
= 0; offset
< 100; offset
+= 4) {
741 inst
= read_memory_integer(pc
+ offset
, 4);
742 if ((inst
& 0xffff0000) == 0x27bd0000) /* addiu $sp,$sp,offset */
744 else if ((inst
& 0xFFE00000) == 0xAFA00000 && (inst
& 0x001F0000))
745 continue; /* sw reg,n($sp) */
747 else if ((inst
& 0xFFE00000) == 0xE7A00000) /* swc1 freg,n($sp) */
749 else if ((inst
& 0xF3E00000) == 0xA3C00000 && (inst
& 0x001F0000))
751 continue; /* reg != $zero */
752 else if (inst
== 0x03A0F021) /* move $s8,$sp */
754 else if ((inst
& 0xFF9F07FF) == 0x00800021) /* move reg,$a0-$a3 */
761 /* FIXME schauer. The following code seems no longer necessary if we
762 always skip the typical prologue instructions. */
768 /* Well, it looks like a frameless. Let's make sure.
769 Note that we are not called on the current PC,
770 but on the function`s start PC, and I have definitely
771 seen optimized code that adjusts the SP quite later */
772 b
= block_for_pc(pc
);
775 f
= lookup_symbol(MIPS_EFI_SYMBOL_NAME
, b
, LABEL_NAMESPACE
, 0, NULL
);
777 /* Ideally, I would like to use the adjusted info
778 from mips_frame_info(), but for all practical
779 purposes it will not matter (and it would require
780 a different definition of SKIP_PROLOGUE())
782 Actually, it would not hurt to skip the storing
783 of arguments on the stack as well. */
784 if (((mips_extra_func_info_t
)SYMBOL_VALUE(f
))->pdr
.frameoffset
)
791 /* Given a return value in `regbuf' with a type `valtype',
792 extract and copy its value into `valbuf'. */
794 mips_extract_return_value (valtype
, regbuf
, valbuf
)
795 struct type
*valtype
;
796 char regbuf
[REGISTER_BYTES
];
801 regnum
= TYPE_CODE (valtype
) == TYPE_CODE_FLT
&& mips_fpu
? FP0_REGNUM
: 2;
803 memcpy (valbuf
, regbuf
+ REGISTER_BYTE (regnum
), TYPE_LENGTH (valtype
));
804 #ifdef REGISTER_CONVERT_TO_TYPE
805 REGISTER_CONVERT_TO_TYPE(regnum
, valtype
, valbuf
);
809 /* Given a return value in `regbuf' with a type `valtype',
810 write it's value into the appropriate register. */
812 mips_store_return_value (valtype
, valbuf
)
813 struct type
*valtype
;
817 char raw_buffer
[MAX_REGISTER_RAW_SIZE
];
819 regnum
= TYPE_CODE (valtype
) == TYPE_CODE_FLT
&& mips_fpu
? FP0_REGNUM
: 2;
820 memcpy(raw_buffer
, valbuf
, TYPE_LENGTH (valtype
));
822 #ifdef REGISTER_CONVERT_FROM_TYPE
823 REGISTER_CONVERT_FROM_TYPE(regnum
, valtype
, raw_buffer
);
826 write_register_bytes(REGISTER_BYTE (regnum
), raw_buffer
, TYPE_LENGTH (valtype
));
829 /* Let the user turn off floating point and set the fence post for
830 heuristic_proc_start. */
833 _initialize_mips_tdep ()
836 (add_set_cmd ("mipsfpu", class_support
, var_boolean
,
838 "Set use of floating point coprocessor.\n\
839 Turn off to avoid using floating point instructions when calling functions\n\
840 or dealing with return values.", &setlist
),
844 (add_set_cmd ("heuristic-fence-post", class_support
, var_uinteger
,
845 (char *) &heuristic_fence_post
,
846 "Set the distance searched for the start of a function.\n\
847 Set number of bytes to be searched backward to find the beginning of a\n\
848 function without symbols.", &setlist
),