4b6d8e25c44d09b1eaac99be88dffb1e8a167245
1 /* Target-machine dependent code for Zilog Z8000, for GDB.
2 Copyright (C) 1992, 1993, 1994, 2001 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 Contributed by Steve Chamberlain
36 #include "value.h" /* For read_register() */
39 static int read_memory_pointer (CORE_ADDR x
);
41 /* Return the saved PC from this frame.
43 If the frame has a memory copy of SRP_REGNUM, use that. If not,
44 just use the register SRP_REGNUM itself. */
47 z8k_frame_saved_pc (struct frame_info
*frame
)
49 return read_memory_pointer (frame
->frame
+ (BIG
? 4 : 2));
52 #define IS_PUSHL(x) (BIG ? ((x & 0xfff0) == 0x91e0):((x & 0xfff0) == 0x91F0))
53 #define IS_PUSHW(x) (BIG ? ((x & 0xfff0) == 0x93e0):((x & 0xfff0)==0x93f0))
54 #define IS_MOVE_FP(x) (BIG ? x == 0xa1ea : x == 0xa1fa)
55 #define IS_MOV_SP_FP(x) (BIG ? x == 0x94ea : x == 0x0d76)
56 #define IS_SUB2_SP(x) (x==0x1b87)
57 #define IS_MOVK_R5(x) (x==0x7905)
58 #define IS_SUB_SP(x) ((x & 0xffff) == 0x020f)
59 #define IS_PUSH_FP(x) (BIG ? (x == 0x93ea) : (x == 0x93fa))
61 /* work out how much local space is on the stack and
62 return the pc pointing to the first push */
65 skip_adjust (CORE_ADDR pc
, int *size
)
69 if (IS_PUSH_FP (read_memory_short (pc
))
70 && IS_MOV_SP_FP (read_memory_short (pc
+ 2)))
72 /* This is a function with an explict frame pointer */
74 *size
+= 2; /* remember the frame pointer */
77 /* remember any stack adjustment */
78 if (IS_SUB_SP (read_memory_short (pc
)))
80 *size
+= read_memory_short (pc
+ 2);
86 static CORE_ADDR
examine_frame (CORE_ADDR
, CORE_ADDR
* regs
, CORE_ADDR
);
88 examine_frame (CORE_ADDR pc
, CORE_ADDR
*regs
, CORE_ADDR sp
)
90 int w
= read_memory_short (pc
);
94 for (regno
= 0; regno
< NUM_REGS
; regno
++)
97 while (IS_PUSHW (w
) || IS_PUSHL (w
))
99 /* work out which register is being pushed to where */
102 regs
[w
& 0xf] = offset
;
103 regs
[(w
& 0xf) + 1] = offset
+ 2;
108 regs
[w
& 0xf] = offset
;
112 w
= read_memory_short (pc
);
120 else if (IS_SUB_SP (w
))
122 /* Subtracting a value from the sp, so were in a function
123 which needs stack space for locals, but has no fp. We fake up
124 the values as if we had an fp */
125 regs
[FP_REGNUM
] = sp
;
129 /* This one didn't have an fp, we'll fake it up */
130 regs
[SP_REGNUM
] = sp
;
132 /* stack pointer contains address of next frame */
133 /* regs[fp_regnum()] = fp; */
134 regs
[SP_REGNUM
] = sp
;
139 z8k_skip_prologue (CORE_ADDR start_pc
)
141 CORE_ADDR dummy
[NUM_REGS
];
143 return examine_frame (start_pc
, dummy
, 0);
147 z8k_addr_bits_remove (CORE_ADDR addr
)
149 return (addr
& PTR_MASK
);
153 read_memory_pointer (CORE_ADDR x
)
155 return read_memory_integer (ADDR_BITS_REMOVE (x
), BIG
? 4 : 2);
159 z8k_frame_chain (struct frame_info
*thisframe
)
161 if (thisframe
->prev
== 0)
163 /* This is the top of the stack, let's get the sp for real */
165 if (!inside_entry_file (thisframe
->pc
))
167 return read_memory_pointer (thisframe
->frame
);
175 internal_error (__FILE__
, __LINE__
, "failed internal consistency check");
178 /* Put here the code to store, into a struct frame_saved_regs,
179 the addresses of the saved registers of frame described by FRAME_INFO.
180 This includes special registers such as pc and fp saved in special
181 ways in the stack frame. sp is even more special:
182 the address we return for it IS the sp for the next frame. */
185 z8k_frame_init_saved_regs (struct frame_info
*frame_info
)
190 frame_saved_regs_zalloc (frame_info
);
191 pc
= get_pc_function_start (frame_info
->pc
);
193 /* wander down the instruction stream */
194 examine_frame (pc
, frame_info
->saved_regs
, frame_info
->frame
);
199 z8k_push_dummy_frame (void)
201 internal_error (__FILE__
, __LINE__
, "failed internal consistency check");
205 gdb_print_insn_z8k (bfd_vma memaddr
, disassemble_info
*info
)
208 return print_insn_z8001 (memaddr
, info
);
210 return print_insn_z8002 (memaddr
, info
);
213 /* Fetch the instruction at ADDR, returning 0 if ADDR is beyond LIM or
214 is not the address of a valid instruction, the address of the next
215 instruction beyond ADDR otherwise. *PWORD1 receives the first word
216 of the instruction. */
219 NEXT_PROLOGUE_INSN (CORE_ADDR addr
, CORE_ADDR lim
, short *pword1
)
224 read_memory (addr
, buf
, 2);
225 *pword1
= extract_signed_integer (buf
, 2);
233 /* Put here the code to store, into a struct frame_saved_regs,
234 the addresses of the saved registers of frame described by FRAME_INFO.
235 This includes special registers such as pc and fp saved in special
236 ways in the stack frame. sp is even more special:
237 the address we return for it IS the sp for the next frame.
239 We cache the result of doing this in the frame_cache_obstack, since
240 it is fairly expensive. */
243 frame_find_saved_regs (struct frame_info
*fip
, struct frame_saved_regs
*fsrp
)
250 memset (fsrp
, 0, sizeof *fsrp
);
252 pc
= skip_adjust (get_pc_function_start (fip
->pc
), &locals
);
255 adr
= FRAME_FP (fip
) - locals
;
256 for (i
= 0; i
< 8; i
++)
258 int word
= read_memory_short (pc
);
263 fsrp
->regs
[word
& 0xf] = adr
;
264 fsrp
->regs
[(word
& 0xf) + 1] = adr
- 2;
267 else if (IS_PUSHW (word
))
269 fsrp
->regs
[word
& 0xf] = adr
;
278 fsrp
->regs
[PC_REGNUM
] = fip
->frame
+ 4;
279 fsrp
->regs
[FP_REGNUM
] = fip
->frame
;
285 z8k_saved_pc_after_call (struct frame_info
*frame
)
287 return ADDR_BITS_REMOVE
288 (read_memory_integer (read_register (SP_REGNUM
), PTR_SIZE
));
293 extract_return_value (struct type
*type
, char *regbuf
, char *valbuf
)
296 int len
= TYPE_LENGTH (type
);
298 for (b
= 0; b
< len
; b
+= 2)
304 memcpy (valbuf
+ b
, regbuf
+ b
, todo
);
309 write_return_value (struct type
*type
, char *valbuf
)
314 for (len
= 0; len
< TYPE_LENGTH (type
); len
+= 2)
315 write_register_bytes (REGISTER_BYTE (len
/ 2 + 2), valbuf
+ len
, 2);
319 store_struct_return (CORE_ADDR addr
, CORE_ADDR sp
)
321 write_register (2, addr
);
326 z8k_print_register_hook (int regno
)
328 if ((regno
& 1) == 0 && regno
< 16)
332 read_relative_register_raw_bytes (regno
, (char *) (l
+ 0));
333 read_relative_register_raw_bytes (regno
+ 1, (char *) (l
+ 1));
334 printf_unfiltered ("\t");
335 printf_unfiltered ("%04x%04x", l
[0], l
[1]);
338 if ((regno
& 3) == 0 && regno
< 16)
342 read_relative_register_raw_bytes (regno
, (char *) (l
+ 0));
343 read_relative_register_raw_bytes (regno
+ 1, (char *) (l
+ 1));
344 read_relative_register_raw_bytes (regno
+ 2, (char *) (l
+ 2));
345 read_relative_register_raw_bytes (regno
+ 3, (char *) (l
+ 3));
347 printf_unfiltered ("\t");
348 printf_unfiltered ("%04x%04x%04x%04x", l
[0], l
[1], l
[2], l
[3]);
355 read_relative_register_raw_bytes (regno
, (char *) (&rval
));
357 printf_unfiltered ("\n");
358 for (i
= 0; i
< 10; i
+= 2)
360 printf_unfiltered ("(sp+%d=%04x)", i
,
361 (unsigned int)read_memory_short (rval
+ i
));
372 struct cmd_list_element
*setmemorylist
;
375 z8k_set_pointer_size (int newsize
)
377 static int oldsize
= 0;
379 if (oldsize
!= newsize
)
381 printf_unfiltered ("pointer size set to %d bits\n", newsize
);
391 /* FIXME: This code should be using the GDBARCH framework to
392 handle changed type sizes. If this problem is ever fixed
393 (the direct reference to _initialize_gdbtypes() below
394 eliminated) then Makefile.in should be updated so that
395 z8k-tdep.c is again compiled with -Werror. */
396 _initialize_gdbtypes ();
401 segmented_command (char *args
, int from_tty
)
403 z8k_set_pointer_size (32);
407 unsegmented_command (char *args
, int from_tty
)
409 z8k_set_pointer_size (16);
413 set_memory (char *args
, int from_tty
)
415 printf_unfiltered ("\"set memory\" must be followed by the name of a memory subcommand.\n");
416 help_list (setmemorylist
, "set memory ", -1, gdb_stdout
);
420 _initialize_z8ktdep (void)
422 tm_print_insn
= gdb_print_insn_z8k
;
424 add_prefix_cmd ("memory", no_class
, set_memory
,
425 "set the memory model", &setmemorylist
, "set memory ", 0,
427 add_cmd ("segmented", class_support
, segmented_command
,
428 "Set segmented memory model.", &setmemorylist
);
429 add_cmd ("unsegmented", class_support
, unsegmented_command
,
430 "Set unsegmented memory model.", &setmemorylist
);