1 /* Target-machine dependent code for Zilog Z8000, for GDB.
2 Copyright (C) 1992, 1993, 1994 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, Boston, MA 02111-1307, USA. */
21 Contributed by Steve Chamberlain
35 /* Return the saved PC from this frame.
37 If the frame has a memory copy of SRP_REGNUM, use that. If not,
38 just use the register SRP_REGNUM itself. */
41 frame_saved_pc (frame)
42 struct frame_info *frame;
44 return read_memory_pointer (frame->frame + (BIG ? 4 : 2));
47 #define IS_PUSHL(x) (BIG ? ((x & 0xfff0) == 0x91e0):((x & 0xfff0) == 0x91F0))
48 #define IS_PUSHW(x) (BIG ? ((x & 0xfff0) == 0x93e0):((x & 0xfff0)==0x93f0))
49 #define IS_MOVE_FP(x) (BIG ? x == 0xa1ea : x == 0xa1fa)
50 #define IS_MOV_SP_FP(x) (BIG ? x == 0x94ea : x == 0x0d76)
51 #define IS_SUB2_SP(x) (x==0x1b87)
52 #define IS_MOVK_R5(x) (x==0x7905)
53 #define IS_SUB_SP(x) ((x & 0xffff) == 0x020f)
54 #define IS_PUSH_FP(x) (BIG ? (x == 0x93ea) : (x == 0x93fa))
56 /* work out how much local space is on the stack and
57 return the pc pointing to the first push */
60 skip_adjust (pc, size)
66 if (IS_PUSH_FP (read_memory_short (pc))
67 && IS_MOV_SP_FP (read_memory_short (pc + 2)))
69 /* This is a function with an explict frame pointer */
71 *size += 2; /* remember the frame pointer */
74 /* remember any stack adjustment */
75 if (IS_SUB_SP (read_memory_short (pc)))
77 *size += read_memory_short (pc + 2);
83 static CORE_ADDR examine_frame PARAMS ((CORE_ADDR, CORE_ADDR *regs, CORE_ADDR));
85 examine_frame (pc, regs, 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 (start_pc)
142 CORE_ADDR dummy[NUM_REGS];
144 return examine_frame (start_pc, dummy, 0);
148 z8k_addr_bits_remove (addr)
151 return (addr & PTR_MASK);
155 read_memory_pointer (x)
158 return read_memory_integer (ADDR_BITS_REMOVE (x), BIG ? 4 : 2);
162 frame_chain (thisframe)
163 struct frame_info *thisframe;
165 if (thisframe->prev == 0)
167 /* This is the top of the stack, let's get the sp for real */
169 if (!inside_entry_file (thisframe->pc))
171 return read_memory_pointer (thisframe->frame);
182 /* Put here the code to store, into a struct frame_saved_regs,
183 the addresses of the saved registers of frame described by FRAME_INFO.
184 This includes special registers such as pc and fp saved in special
185 ways in the stack frame. sp is even more special:
186 the address we return for it IS the sp for the next frame. */
189 z8k_frame_init_saved_regs (frame_info)
190 struct frame_info *frame_info;
195 frame_saved_regs_zalloc (frame_info);
196 pc = get_pc_function_start (frame_info->pc);
198 /* wander down the instruction stream */
199 examine_frame (pc, frame_info->saved_regs, frame_info->frame);
204 z8k_push_dummy_frame ()
210 gdb_print_insn_z8k (memaddr, info)
212 disassemble_info *info;
215 return print_insn_z8001 (memaddr, info);
217 return print_insn_z8002 (memaddr, info);
220 /* Fetch the instruction at ADDR, returning 0 if ADDR is beyond LIM or
221 is not the address of a valid instruction, the address of the next
222 instruction beyond ADDR otherwise. *PWORD1 receives the first word
223 of the instruction.*/
226 NEXT_PROLOGUE_INSN (addr, lim, pword1)
234 read_memory (addr, buf, 2);
235 *pword1 = extract_signed_integer (buf, 2);
243 /* Put here the code to store, into a struct frame_saved_regs,
244 the addresses of the saved registers of frame described by FRAME_INFO.
245 This includes special registers such as pc and fp saved in special
246 ways in the stack frame. sp is even more special:
247 the address we return for it IS the sp for the next frame.
249 We cache the result of doing this in the frame_cache_obstack, since
250 it is fairly expensive. */
253 frame_find_saved_regs (fip, fsrp)
254 struct frame_info *fip;
255 struct frame_saved_regs *fsrp;
262 memset (fsrp, 0, sizeof *fsrp);
264 pc = skip_adjust (get_pc_function_start (fip->pc), &locals);
267 adr = FRAME_FP (fip) - locals;
268 for (i = 0; i < 8; i++)
270 int word = read_memory_short (pc);
275 fsrp->regs[word & 0xf] = adr;
276 fsrp->regs[(word & 0xf) + 1] = adr - 2;
279 else if (IS_PUSHW (word))
281 fsrp->regs[word & 0xf] = adr;
290 fsrp->regs[PC_REGNUM] = fip->frame + 4;
291 fsrp->regs[FP_REGNUM] = fip->frame;
297 saved_pc_after_call ()
299 return ADDR_BITS_REMOVE
300 (read_memory_integer (read_register (SP_REGNUM), PTR_SIZE));
305 extract_return_value (type, regbuf, valbuf)
311 int len = TYPE_LENGTH (type);
313 for (b = 0; b < len; b += 2)
319 memcpy (valbuf + b, regbuf + b, todo);
324 write_return_value (type, valbuf)
331 for (len = 0; len < TYPE_LENGTH (type); len += 2)
332 write_register_bytes (REGISTER_BYTE (len / 2 + 2), valbuf + len, 2);
336 store_struct_return (addr, sp)
340 write_register (2, addr);
345 print_register_hook (regno)
348 if ((regno & 1) == 0 && regno < 16)
352 read_relative_register_raw_bytes (regno, (char *) (l + 0));
353 read_relative_register_raw_bytes (regno + 1, (char *) (l + 1));
354 printf_unfiltered ("\t");
355 printf_unfiltered ("%04x%04x", l[0], l[1]);
358 if ((regno & 3) == 0 && regno < 16)
362 read_relative_register_raw_bytes (regno, (char *) (l + 0));
363 read_relative_register_raw_bytes (regno + 1, (char *) (l + 1));
364 read_relative_register_raw_bytes (regno + 2, (char *) (l + 2));
365 read_relative_register_raw_bytes (regno + 3, (char *) (l + 3));
367 printf_unfiltered ("\t");
368 printf_unfiltered ("%04x%04x%04x%04x", l[0], l[1], l[2], l[3]);
375 read_relative_register_raw_bytes (regno, (char *) (&rval));
377 printf_unfiltered ("\n");
378 for (i = 0; i < 10; i += 2)
380 printf_unfiltered ("(sp+%d=%04x)", i, read_memory_short (rval + i));
391 struct cmd_list_element *setmemorylist;
394 z8k_set_pointer_size (newsize)
397 static int oldsize = 0;
399 if (oldsize != newsize)
401 printf_unfiltered ("pointer size set to %d bits\n", newsize);
411 _initialize_gdbtypes ();
416 segmented_command (args, from_tty)
420 z8k_set_pointer_size (32);
424 unsegmented_command (args, from_tty)
428 z8k_set_pointer_size (16);
432 set_memory (args, from_tty)
436 printf_unfiltered ("\"set memory\" must be followed by the name of a memory subcommand.\n");
437 help_list (setmemorylist, "set memory ", -1, gdb_stdout);
441 _initialize_z8ktdep ()
443 tm_print_insn = gdb_print_insn_z8k;
445 add_prefix_cmd ("memory", no_class, set_memory,
446 "set the memory model", &setmemorylist, "set memory ", 0,
448 add_cmd ("segmented", class_support, segmented_command,
449 "Set segmented memory model.", &setmemorylist);
450 add_cmd ("unsegmented", class_support, unsegmented_command,
451 "Set unsegmented memory model.", &setmemorylist);