1 /* Motorola m68k native support for GNU/Linux.
3 Copyright 1996, 1998, 2000, 2001, 2002 Free Software Foundation,
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., 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
31 #include <sys/types.h>
34 #include <sys/param.h>
37 #include <sys/ptrace.h>
39 #include <sys/ioctl.h>
41 #include <sys/procfs.h>
50 #include "floatformat.h"
55 /* This table must line up with REGISTER_NAMES in tm-m68k.h */
56 static const int regmap
[] =
58 PT_D0
, PT_D1
, PT_D2
, PT_D3
, PT_D4
, PT_D5
, PT_D6
, PT_D7
,
59 PT_A0
, PT_A1
, PT_A2
, PT_A3
, PT_A4
, PT_A5
, PT_A6
, PT_USP
,
61 /* PT_FP0, ..., PT_FP7 */
62 21, 24, 27, 30, 33, 36, 39, 42,
63 /* PT_FPCR, PT_FPSR, PT_FPIAR */
67 /* Which ptrace request retrieves which registers?
68 These apply to the corresponding SET requests as well. */
69 #define NUM_GREGS (18)
70 #define MAX_NUM_REGS (NUM_GREGS + 11)
73 getregs_supplies (int regno
)
75 return 0 <= regno
&& regno
< NUM_GREGS
;
79 getfpregs_supplies (int regno
)
81 return FP0_REGNUM
<= regno
&& regno
<= FPI_REGNUM
;
84 /* Does the current host support the GETREGS request? */
85 int have_ptrace_getregs
=
86 #ifdef HAVE_PTRACE_GETREGS
95 /* BLOCKEND is the value of u.u_ar0, and points to the place where GS
99 m68k_linux_register_u_addr (int blockend
, int regnum
)
101 return (blockend
+ 4 * regmap
[regnum
]);
105 /* Fetching registers directly from the U area, one at a time. */
107 /* FIXME: This duplicates code from `inptrace.c'. The problem is that we
108 define FETCH_INFERIOR_REGISTERS since we want to use our own versions
109 of {fetch,store}_inferior_registers that use the GETREGS request. This
110 means that the code in `infptrace.c' is #ifdef'd out. But we need to
111 fall back on that code when GDB is running on top of a kernel that
112 doesn't support the GETREGS request. */
115 #define PT_READ_U PTRACE_PEEKUSR
118 #define PT_WRITE_U PTRACE_POKEUSR
121 /* Default the type of the ptrace transfer to int. */
122 #ifndef PTRACE_XFER_TYPE
123 #define PTRACE_XFER_TYPE int
126 /* Fetch one register. */
129 fetch_register (int regno
)
131 /* This isn't really an address. But ptrace thinks of it as one. */
133 char mess
[128]; /* For messages */
135 unsigned int offset
; /* Offset of registers within the u area. */
136 char buf
[MAX_REGISTER_RAW_SIZE
];
139 if (CANNOT_FETCH_REGISTER (regno
))
141 memset (buf
, '\0', REGISTER_RAW_SIZE (regno
)); /* Supply zeroes */
142 supply_register (regno
, buf
);
146 /* Overload thread id onto process id */
147 if ((tid
= TIDGET (inferior_ptid
)) == 0)
148 tid
= PIDGET (inferior_ptid
); /* no thread id, just use process id */
150 offset
= U_REGS_OFFSET
;
152 regaddr
= register_addr (regno
, offset
);
153 for (i
= 0; i
< REGISTER_RAW_SIZE (regno
); i
+= sizeof (PTRACE_XFER_TYPE
))
156 *(PTRACE_XFER_TYPE
*) & buf
[i
] = ptrace (PT_READ_U
, tid
,
157 (PTRACE_ARG3_TYPE
) regaddr
, 0);
158 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
161 sprintf (mess
, "reading register %s (#%d)",
162 REGISTER_NAME (regno
), regno
);
163 perror_with_name (mess
);
166 supply_register (regno
, buf
);
169 /* Fetch register values from the inferior.
170 If REGNO is negative, do this for all registers.
171 Otherwise, REGNO specifies which register (so we can save time). */
174 old_fetch_inferior_registers (int regno
)
178 fetch_register (regno
);
182 for (regno
= 0; regno
< NUM_REGS
; regno
++)
184 fetch_register (regno
);
189 /* Store one register. */
192 store_register (int regno
)
194 /* This isn't really an address. But ptrace thinks of it as one. */
196 char mess
[128]; /* For messages */
198 unsigned int offset
; /* Offset of registers within the u area. */
200 char *buf
= alloca (MAX_REGISTER_RAW_SIZE
);
202 if (CANNOT_STORE_REGISTER (regno
))
207 /* Overload thread id onto process id */
208 if ((tid
= TIDGET (inferior_ptid
)) == 0)
209 tid
= PIDGET (inferior_ptid
); /* no thread id, just use process id */
211 offset
= U_REGS_OFFSET
;
213 regaddr
= register_addr (regno
, offset
);
215 /* Put the contents of regno into a local buffer */
216 regcache_collect (regno
, buf
);
218 /* Store the local buffer into the inferior a chunk at the time. */
219 for (i
= 0; i
< REGISTER_RAW_SIZE (regno
); i
+= sizeof (PTRACE_XFER_TYPE
))
222 ptrace (PT_WRITE_U
, tid
, (PTRACE_ARG3_TYPE
) regaddr
,
223 *(PTRACE_XFER_TYPE
*) (buf
+ i
));
224 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
227 sprintf (mess
, "writing register %s (#%d)",
228 REGISTER_NAME (regno
), regno
);
229 perror_with_name (mess
);
234 /* Store our register values back into the inferior.
235 If REGNO is negative, do this for all registers.
236 Otherwise, REGNO specifies which register (so we can save time). */
239 old_store_inferior_registers (int regno
)
243 store_register (regno
);
247 for (regno
= 0; regno
< NUM_REGS
; regno
++)
249 store_register (regno
);
254 /* Given a pointer to a general register set in /proc format
255 (elf_gregset_t *), unpack the register contents and supply
256 them as gdb's idea of the current register values. */
259 /* Note both m68k-tdep.c and m68klinux-nat.c contain definitions
260 for supply_gregset and supply_fpregset. The definitions
261 in m68k-tdep.c are valid if USE_PROC_FS is defined. Otherwise,
262 the definitions in m68klinux-nat.c will be used. This is a
263 bit of a hack. The supply_* routines do not belong in
264 *_tdep.c files. But, there are several lynx ports that currently
265 depend on these definitions. */
269 /* Prototypes for supply_gregset etc. */
273 supply_gregset (elf_gregset_t
*gregsetp
)
275 elf_greg_t
*regp
= (elf_greg_t
*) gregsetp
;
278 for (regi
= D0_REGNUM
; regi
<= SP_REGNUM
; regi
++)
279 supply_register (regi
, (char *) ®p
[regmap
[regi
]]);
280 supply_register (PS_REGNUM
, (char *) ®p
[PT_SR
]);
281 supply_register (PC_REGNUM
, (char *) ®p
[PT_PC
]);
284 /* Fill register REGNO (if it is a general-purpose register) in
285 *GREGSETPS with the value in GDB's register array. If REGNO is -1,
286 do this for all registers. */
288 fill_gregset (elf_gregset_t
*gregsetp
, int regno
)
290 elf_greg_t
*regp
= (elf_greg_t
*) gregsetp
;
293 for (i
= 0; i
< NUM_GREGS
; i
++)
294 if ((regno
== -1 || regno
== i
))
295 regcache_collect (i
, regp
+ regmap
[i
]);
298 #ifdef HAVE_PTRACE_GETREGS
300 /* Fetch all general-purpose registers from process/thread TID and
301 store their values in GDB's register array. */
308 if (ptrace (PTRACE_GETREGS
, tid
, 0, (int) ®s
) < 0)
312 /* The kernel we're running on doesn't support the GETREGS
313 request. Reset `have_ptrace_getregs'. */
314 have_ptrace_getregs
= 0;
318 perror_with_name ("Couldn't get registers");
321 supply_gregset (®s
);
324 /* Store all valid general-purpose registers in GDB's register array
325 into the process/thread specified by TID. */
328 store_regs (int tid
, int regno
)
332 if (ptrace (PTRACE_GETREGS
, tid
, 0, (int) ®s
) < 0)
333 perror_with_name ("Couldn't get registers");
335 fill_gregset (®s
, regno
);
337 if (ptrace (PTRACE_SETREGS
, tid
, 0, (int) ®s
) < 0)
338 perror_with_name ("Couldn't write registers");
343 static void fetch_regs (int tid
) {}
344 static void store_regs (int tid
, int regno
) {}
349 /* Transfering floating-point registers between GDB, inferiors and cores. */
351 /* What is the address of fpN within the floating-point register set F? */
352 #define FPREG_ADDR(f, n) ((char *) &(f)->fpregs[(n) * 3])
354 /* Fill GDB's register array with the floating-point register values in
358 supply_fpregset (elf_fpregset_t
*fpregsetp
)
362 for (regi
= FP0_REGNUM
; regi
< FPC_REGNUM
; regi
++)
363 supply_register (regi
, FPREG_ADDR (fpregsetp
, regi
- FP0_REGNUM
));
364 supply_register (FPC_REGNUM
, (char *) &fpregsetp
->fpcntl
[0]);
365 supply_register (FPS_REGNUM
, (char *) &fpregsetp
->fpcntl
[1]);
366 supply_register (FPI_REGNUM
, (char *) &fpregsetp
->fpcntl
[2]);
369 /* Fill register REGNO (if it is a floating-point register) in
370 *FPREGSETP with the value in GDB's register array. If REGNO is -1,
371 do this for all registers. */
374 fill_fpregset (elf_fpregset_t
*fpregsetp
, int regno
)
378 /* Fill in the floating-point registers. */
379 for (i
= FP0_REGNUM
; i
< FP0_REGNUM
+ 8; i
++)
380 if (regno
== -1 || regno
== i
)
381 regcache_collect (regno
, FPREG_ADDR (fpregsetp
, regno
- FP0_REGNUM
));
383 /* Fill in the floating-point control registers. */
384 for (i
= FPC_REGNUM
; i
<= FPI_REGNUM
; i
++)
385 if (regno
== -1 || regno
== i
)
386 regcache_collect (regno
, (char *) &fpregsetp
->fpcntl
[regno
- FPC_REGNUM
]);
389 #ifdef HAVE_PTRACE_GETREGS
391 /* Fetch all floating-point registers from process/thread TID and store
392 thier values in GDB's register array. */
395 fetch_fpregs (int tid
)
397 elf_fpregset_t fpregs
;
399 if (ptrace (PTRACE_GETFPREGS
, tid
, 0, (int) &fpregs
) < 0)
400 perror_with_name ("Couldn't get floating point status");
402 supply_fpregset (&fpregs
);
405 /* Store all valid floating-point registers in GDB's register array
406 into the process/thread specified by TID. */
409 store_fpregs (int tid
, int regno
)
411 elf_fpregset_t fpregs
;
413 if (ptrace (PTRACE_GETFPREGS
, tid
, 0, (int) &fpregs
) < 0)
414 perror_with_name ("Couldn't get floating point status");
416 fill_fpregset (&fpregs
, regno
);
418 if (ptrace (PTRACE_SETFPREGS
, tid
, 0, (int) &fpregs
) < 0)
419 perror_with_name ("Couldn't write floating point status");
424 static void fetch_fpregs (int tid
) {}
425 static void store_fpregs (int tid
, int regno
) {}
431 /* Transferring arbitrary registers between GDB and inferior. */
433 /* Fetch register REGNO from the child process. If REGNO is -1, do
434 this for all registers (including the floating point and SSE
438 fetch_inferior_registers (int regno
)
442 /* Use the old method of peeking around in `struct user' if the
443 GETREGS request isn't available. */
444 if (! have_ptrace_getregs
)
446 old_fetch_inferior_registers (regno
);
450 /* GNU/Linux LWP ID's are process ID's. */
451 if ((tid
= TIDGET (inferior_ptid
)) == 0)
452 tid
= PIDGET (inferior_ptid
); /* Not a threaded program. */
454 /* Use the PTRACE_GETFPXREGS request whenever possible, since it
455 transfers more registers in one system call, and we'll cache the
456 results. But remember that fetch_fpxregs can fail, and return
462 /* The call above might reset `have_ptrace_getregs'. */
463 if (! have_ptrace_getregs
)
465 old_fetch_inferior_registers (-1);
473 if (getregs_supplies (regno
))
479 if (getfpregs_supplies (regno
))
485 internal_error (__FILE__
, __LINE__
,
486 "Got request for bad register number %d.", regno
);
489 /* Store register REGNO back into the child process. If REGNO is -1,
490 do this for all registers (including the floating point and SSE
493 store_inferior_registers (int regno
)
497 /* Use the old method of poking around in `struct user' if the
498 SETREGS request isn't available. */
499 if (! have_ptrace_getregs
)
501 old_store_inferior_registers (regno
);
505 /* GNU/Linux LWP ID's are process ID's. */
506 if ((tid
= TIDGET (inferior_ptid
)) == 0)
507 tid
= PIDGET (inferior_ptid
); /* Not a threaded program. */
509 /* Use the PTRACE_SETFPREGS requests whenever possible, since it
510 transfers more registers in one system call. But remember that
511 store_fpregs can fail, and return zero. */
514 store_regs (tid
, regno
);
515 store_fpregs (tid
, regno
);
519 if (getregs_supplies (regno
))
521 store_regs (tid
, regno
);
525 if (getfpregs_supplies (regno
))
527 store_fpregs (tid
, regno
);
531 internal_error (__FILE__
, __LINE__
,
532 "Got request to store bad register number %d.", regno
);
535 /* Interpreting register set info found in core files. */
537 /* Provide registers to GDB from a core file.
539 (We can't use the generic version of this function in
540 core-regset.c, because we need to use elf_gregset_t instead of
543 CORE_REG_SECT points to an array of bytes, which are the contents
544 of a `note' from a core file which BFD thinks might contain
545 register contents. CORE_REG_SIZE is its size.
547 WHICH says which register set corelow suspects this is:
548 0 --- the general-purpose register set, in elf_gregset_t format
549 2 --- the floating-point register set, in elf_fpregset_t format
551 REG_ADDR isn't used on GNU/Linux. */
554 fetch_core_registers (char *core_reg_sect
, unsigned core_reg_size
,
555 int which
, CORE_ADDR reg_addr
)
557 elf_gregset_t gregset
;
558 elf_fpregset_t fpregset
;
563 if (core_reg_size
!= sizeof (gregset
))
564 warning ("Wrong size gregset in core file.");
567 memcpy (&gregset
, core_reg_sect
, sizeof (gregset
));
568 supply_gregset (&gregset
);
573 if (core_reg_size
!= sizeof (fpregset
))
574 warning ("Wrong size fpregset in core file.");
577 memcpy (&fpregset
, core_reg_sect
, sizeof (fpregset
));
578 supply_fpregset (&fpregset
);
583 /* We've covered all the kinds of registers we know about here,
584 so this must be something we wouldn't know what to do with
585 anyway. Just ignore it. */
594 return (sizeof (struct user
));
597 /* Check whether insn1 and insn2 are parts of a signal trampoline. */
599 #define IS_SIGTRAMP(insn1, insn2) \
600 (/* addaw #20,sp; moveq #119,d0; trap #0 */ \
601 (insn1 == 0xdefc0014 && insn2 == 0x70774e40) \
602 /* moveq #119,d0; trap #0 */ \
603 || insn1 == 0x70774e40)
605 #define IS_RT_SIGTRAMP(insn1, insn2) \
606 (/* movel #173,d0; trap #0 */ \
607 (insn1 == 0x203c0000 && insn2 == 0x00ad4e40) \
608 /* moveq #82,d0; notb d0; trap #0 */ \
609 || (insn1 == 0x70524600 && (insn2 >> 16) == 0x4e40))
611 /* Return non-zero if PC points into the signal trampoline. For the sake
612 of m68k_linux_frame_saved_pc we also distinguish between non-RT and RT
613 signal trampolines. */
616 m68k_linux_in_sigtramp (CORE_ADDR pc
)
620 unsigned long insn0
, insn1
, insn2
;
622 if (read_memory_nobpt (pc
- 4, buf
, sizeof (buf
)))
624 insn1
= extract_unsigned_integer (buf
+ 4, 4);
625 insn2
= extract_unsigned_integer (buf
+ 8, 4);
626 if (IS_SIGTRAMP (insn1
, insn2
))
628 if (IS_RT_SIGTRAMP (insn1
, insn2
))
631 insn0
= extract_unsigned_integer (buf
, 4);
632 if (IS_SIGTRAMP (insn0
, insn1
))
634 if (IS_RT_SIGTRAMP (insn0
, insn1
))
637 insn0
= (insn0
<< 16) | (insn1
>> 16);
638 insn1
= (insn1
<< 16) | (insn2
>> 16);
639 if (IS_SIGTRAMP (insn0
, insn1
))
641 if (IS_RT_SIGTRAMP (insn0
, insn1
))
647 /* Offset to saved PC in sigcontext, from <asm/sigcontext.h>. */
648 #define SIGCONTEXT_PC_OFFSET 26
650 /* Offset to saved PC in ucontext, from <asm/ucontext.h>. */
651 #define UCONTEXT_PC_OFFSET 88
653 /* Get saved user PC for sigtramp from sigcontext or ucontext. */
656 m68k_linux_sigtramp_saved_pc (struct frame_info
*frame
)
658 CORE_ADDR sigcontext_addr
;
659 char buf
[TARGET_PTR_BIT
/ TARGET_CHAR_BIT
];
660 int ptrbytes
= TARGET_PTR_BIT
/ TARGET_CHAR_BIT
;
661 int sigcontext_offs
= (2 * TARGET_INT_BIT
) / TARGET_CHAR_BIT
;
663 /* Get sigcontext address, it is the third parameter on the stack. */
665 sigcontext_addr
= read_memory_integer (FRAME_ARGS_ADDRESS (frame
->next
)
670 sigcontext_addr
= read_memory_integer (read_register (SP_REGNUM
)
674 /* Don't cause a memory_error when accessing sigcontext in case the
675 stack layout has changed or the stack is corrupt. */
676 if (m68k_linux_in_sigtramp (frame
->pc
) == 2)
677 target_read_memory (sigcontext_addr
+ UCONTEXT_PC_OFFSET
, buf
, ptrbytes
);
679 target_read_memory (sigcontext_addr
+ SIGCONTEXT_PC_OFFSET
, buf
, ptrbytes
);
680 return extract_unsigned_integer (buf
, ptrbytes
);
683 /* Return the saved program counter for FRAME. */
686 m68k_linux_frame_saved_pc (struct frame_info
*frame
)
688 if (frame
->signal_handler_caller
)
689 return m68k_linux_sigtramp_saved_pc (frame
);
691 return read_memory_integer (frame
->frame
+ 4, 4);
694 /* Register that we are able to handle GNU/Linux ELF core file
697 static struct core_fns linux_elf_core_fns
=
699 bfd_target_elf_flavour
, /* core_flavour */
700 default_check_format
, /* check_format */
701 default_core_sniffer
, /* core_sniffer */
702 fetch_core_registers
, /* core_read_registers */
707 _initialize_m68k_linux_nat (void)
709 add_core_fns (&linux_elf_core_fns
);