Remove tdesc stuff. Remove FRAME_CHAIN_COMBINE from all tm-*.h files,
[deliverable/binutils-gdb.git] / gdb / tm-68k.h
CommitLineData
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1/* Parameters for execution on a 68000 series machine.
2 Copyright (C) 1986, 1987, 1989, 1990 Free Software Foundation, Inc.
3
4This file is part of GDB.
5
99a7de40 6This program is free software; you can redistribute it and/or modify
dd3b648e 7it under the terms of the GNU General Public License as published by
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8the Free Software Foundation; either version 2 of the License, or
9(at your option) any later version.
dd3b648e 10
99a7de40 11This program is distributed in the hope that it will be useful,
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12but WITHOUT ANY WARRANTY; without even the implied warranty of
13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14GNU General Public License for more details.
15
16You should have received a copy of the GNU General Public License
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17along with this program; if not, write to the Free Software
18Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
dd3b648e 19
84d82b1c 20/* Generic 68000 stuff, to be included by other tm-*.h files.
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21 Define HAVE_68881 if that is the case. */
22
23#if defined (HAVE_68881)
24#define IEEE_FLOAT 1
25#endif
26
27/* Define the bit, byte, and word ordering of the machine. */
28#define TARGET_BYTE_ORDER BIG_ENDIAN
29
30/* Offset from address of function to start of its code.
31 Zero on most machines. */
32
33#define FUNCTION_START_OFFSET 0
34
35/* Advance PC across any function entry prologue instructions
36 to reach some "real" code. */
37
38#define SKIP_PROLOGUE(pc) \
39{ register int op = read_memory_integer (pc, 2); \
40 if (op == 0047126) \
41 pc += 4; /* Skip link #word */ \
42 else if (op == 0044016) \
43 pc += 6; /* Skip link #long */ \
44 /* Not sure why branches are here. */ \
45 /* From m-isi.h, m-altos.h */ \
46 else if (op == 0060000) \
47 pc += 4; /* Skip bra #word */ \
48 else if (op == 00600377) \
49 pc += 6; /* skip bra #long */ \
50 else if ((op & 0177400) == 0060000) \
51 pc += 2; /* skip bra #char */ \
52}
53
54/* Immediately after a function call, return the saved pc.
55 Can't always go through the frames for this because on some machines
56 the new frame is not set up until the new function executes
57 some instructions. */
58
59#define SAVED_PC_AFTER_CALL(frame) \
60read_memory_integer (read_register (SP_REGNUM), 4)
61
62/* Stack grows downward. */
63
64#define INNER_THAN <
65
66/* Sequence of bytes for breakpoint instruction.
67 This is a TRAP instruction. The last 4 bits (0xf below) is the
84d82b1c 68 vector. Systems which don't use 0xf should define BPT_VECTOR
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69 themselves before including this file. */
70
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71#if !defined BPT_VECTOR
72#define BPT_VECTOR 0xf
73#endif
74
dd3b648e 75#if !defined (BREAKPOINT)
84d82b1c 76#define BREAKPOINT {0x4e, (0x40 | BPT_VECTOR)}
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77#endif
78
79/* If your kernel resets the pc after the trap happens you may need to
dcd15e5e 80 define this before including this file. */
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81
82#if !defined (DECR_PC_AFTER_BREAK)
83#define DECR_PC_AFTER_BREAK 2
84#endif
85
86/* Nonzero if instruction at PC is a return instruction. */
87/* Allow any of the return instructions, including a trapv and a return
88 from interupt. */
89
90#define ABOUT_TO_RETURN(pc) ((read_memory_integer (pc, 2) & ~0x3) == 0x4e74)
91
92/* Return 1 if P points to an invalid floating point value. */
93
94#define INVALID_FLOAT(p, len) 0 /* Just a first guess; not checked */
95
96/* Say how long registers are. */
97
98#define REGISTER_TYPE long
99
100#if defined (HAVE_68881)
39d2bcca 101# if defined (GDB_TARGET_IS_SUN3)
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102 /* Sun3 status includes fpflags, which shows whether the FPU has been used
103 by the process, and whether the FPU was done with an instruction or
104 was interrupted in the middle of a long instruction. See
105 <machine/reg.h>. */
106 /* a&d, pc,sr, fp, fpstat, fpflags */
107# define NUM_REGS 31
108# define REGISTER_BYTES (16*4 + 8 + 8*12 + 3*4 + 4)
109# else /* Not sun3. */
110# define NUM_REGS 29
111# define REGISTER_BYTES (16*4 + 8 + 8*12 + 3*4)
112# endif /* Not sun3. */
113#else /* No 68881. */
114# define NUM_REGS 18
115# define REGISTER_BYTES (16*4 + 8)
116#endif /* No 68881. */
117
118/* Index within `registers' of the first byte of the space for
119 register N. */
120
121#if defined (HAVE_68881)
122#define REGISTER_BYTE(N) \
123 ((N) >= FPC_REGNUM ? (((N) - FPC_REGNUM) * 4) + 168 \
124 : (N) >= FP0_REGNUM ? (((N) - FP0_REGNUM) * 12) + 72 \
125 : (N) * 4)
126
127/* Number of bytes of storage in the actual machine representation
128 for register N. On the 68000, all regs are 4 bytes
129 except the floating point regs which are 12 bytes. */
130/* Note that the unsigned cast here forces the result of the
131 subtraction to very high positive values if N < FP0_REGNUM */
132
133#define REGISTER_RAW_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 8 ? 12 : 4)
134
135/* Number of bytes of storage in the program's representation
136 for register N. On the 68000, all regs are 4 bytes
137 except the floating point regs which are 8-byte doubles. */
138
139#define REGISTER_VIRTUAL_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 8 ? 8 : 4)
140
141/* Largest value REGISTER_RAW_SIZE can have. */
142
143#define MAX_REGISTER_RAW_SIZE 12
144
145/* Largest value REGISTER_VIRTUAL_SIZE can have. */
146
147#define MAX_REGISTER_VIRTUAL_SIZE 8
148
149/* Nonzero if register N requires conversion
150 from raw format to virtual format. */
151
152#define REGISTER_CONVERTIBLE(N) (((unsigned)(N) - FP0_REGNUM) < 8)
153
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154/* Put the declaration out here because if it's in the macros, PCC
155 will complain. */
9fa28378 156extern struct ext_format ext_format_68881;
de6060de 157
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158/* Convert data from raw format for register REGNUM
159 to virtual format for register REGNUM. */
160
161#define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO) \
162{ \
dd3b648e 163 if ((REGNUM) >= FP0_REGNUM && (REGNUM) < FPC_REGNUM) \
9fa28378 164 ieee_extended_to_double (&ext_format_68881, (FROM), (double *)(TO)); \
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165 else \
166 bcopy ((FROM), (TO), 4); \
167}
168
169/* Convert data from virtual format for register REGNUM
170 to raw format for register REGNUM. */
171
172#define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO) \
173{ \
dd3b648e 174 if ((REGNUM) >= FP0_REGNUM && (REGNUM) < FPC_REGNUM) \
9fa28378 175 double_to_ieee_extended (&ext_format_68881, (double *)(FROM), (TO)); \
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176 else \
177 bcopy ((FROM), (TO), 4); \
178}
179
180/* Return the GDB type object for the "standard" data type
181 of data in register N. */
182/* Note, for registers which contain addresses return
183 pointer to void, not pointer to char, because we don't
184 want to attempt to print the string after printing the address. */
185#define REGISTER_VIRTUAL_TYPE(N) \
186 (((unsigned)(N) - FP0_REGNUM) < 8 ? builtin_type_double : \
187 (N) == PC_REGNUM || (N) == FP_REGNUM || (N) == SP_REGNUM ? \
188 lookup_pointer_type (builtin_type_void) : builtin_type_int)
189
190#else /* no 68881. */
191/* Index within `registers' of the first byte of the space for
192 register N. */
193
194#define REGISTER_BYTE(N) ((N) * 4)
195
196/* Number of bytes of storage in the actual machine representation
197 for register N. On the 68000, all regs are 4 bytes. */
198
199#define REGISTER_RAW_SIZE(N) 4
200
201/* Number of bytes of storage in the program's representation
202 for register N. On the 68000, all regs are 4 bytes. */
203
204#define REGISTER_VIRTUAL_SIZE(N) 4
205
206/* Largest value REGISTER_RAW_SIZE can have. */
207
208#define MAX_REGISTER_RAW_SIZE 4
209
210/* Largest value REGISTER_VIRTUAL_SIZE can have. */
211
212#define MAX_REGISTER_VIRTUAL_SIZE 4
213
214/* Nonzero if register N requires conversion
215 from raw format to virtual format. */
216
217#define REGISTER_CONVERTIBLE(N) 0
218
219/* Convert data from raw format for register REGNUM
220 to virtual format for register REGNUM. */
221
222#define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO) bcopy ((FROM), (TO), 4);
223
224/* Convert data from virtual format for register REGNUM
225 to raw format for register REGNUM. */
226
227#define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO) bcopy ((FROM), (TO), 4);
228
229/* Return the GDB type object for the "standard" data type
230 of data in register N. */
231
232#define REGISTER_VIRTUAL_TYPE(N) builtin_type_int
233
234#endif /* No 68881. */
235
236/* Initializer for an array of names of registers.
237 Entries beyond the first NUM_REGS are ignored. */
238
239#define REGISTER_NAMES \
240 {"d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7", \
241 "a0", "a1", "a2", "a3", "a4", "a5", "fp", "sp", \
242 "ps", "pc", \
243 "fp0", "fp1", "fp2", "fp3", "fp4", "fp5", "fp6", "fp7", \
244 "fpcontrol", "fpstatus", "fpiaddr", "fpcode", "fpflags" }
245
246/* Register numbers of various important registers.
247 Note that some of these values are "real" register numbers,
248 and correspond to the general registers of the machine,
249 and some are "phony" register numbers which are too large
250 to be actual register numbers as far as the user is concerned
251 but do serve to get the desired values when passed to read_register. */
252
253#define A1_REGNUM 9
254#define FP_REGNUM 14 /* Contains address of executing stack frame */
255#define SP_REGNUM 15 /* Contains address of top of stack */
256#define PS_REGNUM 16 /* Contains processor status */
257#define PC_REGNUM 17 /* Contains program counter */
258#if defined (HAVE_68881)
259#define FP0_REGNUM 18 /* Floating point register 0 */
260#define FPC_REGNUM 26 /* 68881 control register */
261#define FPS_REGNUM 27 /* 68881 status register */
afe4ca15 262#define FPI_REGNUM 28 /* 68881 iaddr register */
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263#endif /* 68881. */
264
265/* Store the address of the place in which to copy the structure the
266 subroutine will return. This is called from call_function. */
267
268#define STORE_STRUCT_RETURN(ADDR, SP) \
269 { write_register (A1_REGNUM, (ADDR)); }
270
271/* Extract from an array REGBUF containing the (raw) register state
272 a function return value of type TYPE, and copy that, in virtual format,
273 into VALBUF. This is assuming that floating point values are returned
274 as doubles in d0/d1. */
275
276#if !defined (EXTRACT_RETURN_VALUE)
277#define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
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278 bcopy ((char *)(REGBUF) + \
279 (TYPE_LENGTH(TYPE) >= 4 ? 0 : 4 - TYPE_LENGTH(TYPE)), \
280 VALBUF, TYPE_LENGTH(TYPE))
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281#endif
282
283/* Write into appropriate registers a function return value
284 of type TYPE, given in virtual format. Assumes floats are passed
285 in d0/d1. */
286
287#if !defined (STORE_RETURN_VALUE)
288#define STORE_RETURN_VALUE(TYPE,VALBUF) \
289 write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
290#endif
291
292/* Extract from an array REGBUF containing the (raw) register state
293 the address in which a function should return its structure value,
294 as a CORE_ADDR (or an expression that can be used as one). */
295
e1ce8aa5 296#define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(CORE_ADDR *)(REGBUF))
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297\f
298/* Describe the pointer in each stack frame to the previous stack frame
299 (its caller). */
300
301/* FRAME_CHAIN takes a frame's nominal address
302 and produces the frame's chain-pointer.
303
dd3b648e 304 However, if FRAME_CHAIN_VALID returns zero,
e140f1da 305 it means the given frame is the outermost one and has no caller. */
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306
307/* In the case of the 68000, the frame's nominal address
308 is the address of a 4-byte word containing the calling frame's address. */
309
310#define FRAME_CHAIN(thisframe) \
311 (outside_startup_file ((thisframe)->pc) ? \
312 read_memory_integer ((thisframe)->frame, 4) :\
313 0)
314
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315#if defined (FRAME_CHAIN_VALID_ALTERNATE)
316
317/* Use the alternate method of avoiding running up off the end of
318 the frame chain or following frames back into the startup code.
319 See the comments in blockframe.c */
320
321#define FRAME_CHAIN_VALID(chain, thisframe) \
322 (chain != 0 \
323 && !(inside_main_scope ((thisframe)->pc)) \
324 && !(inside_entry_scope ((thisframe)->pc)))
325
326#else
327
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328#define FRAME_CHAIN_VALID(chain, thisframe) \
329 (chain != 0 && outside_startup_file (FRAME_SAVED_PC (thisframe)))
330
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331#endif /* FRAME_CHAIN_VALID_ALTERNATE */
332
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333/* Define other aspects of the stack frame. */
334
335/* A macro that tells us whether the function invocation represented
336 by FI does not have a frame on the stack associated with it. If it
337 does not, FRAMELESS is set to 1, else 0. */
338#define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \
339 (FRAMELESS) = frameless_look_for_prologue(FI)
340
341#define FRAME_SAVED_PC(FRAME) (read_memory_integer ((FRAME)->frame + 4, 4))
342
343#define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
344
345#define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
346
347/* Set VAL to the number of args passed to frame described by FI.
348 Can set VAL to -1, meaning no way to tell. */
349
350/* We can't tell how many args there are
351 now that the C compiler delays popping them. */
352#if !defined (FRAME_NUM_ARGS)
353#define FRAME_NUM_ARGS(val,fi) (val = -1)
354#endif
355
356/* Return number of bytes at start of arglist that are not really args. */
357
358#define FRAME_ARGS_SKIP 8
359
360/* Put here the code to store, into a struct frame_saved_regs,
361 the addresses of the saved registers of frame described by FRAME_INFO.
362 This includes special registers such as pc and fp saved in special
363 ways in the stack frame. sp is even more special:
364 the address we return for it IS the sp for the next frame. */
365
366#if !defined (FRAME_FIND_SAVED_REGS)
367#if defined (HAVE_68881)
368#define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
369{ register int regnum; \
370 register int regmask; \
371 register CORE_ADDR next_addr; \
372 register CORE_ADDR pc; \
373 int nextinsn; \
374 bzero (&frame_saved_regs, sizeof frame_saved_regs); \
375 if ((frame_info)->pc >= (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM*4 - 8*12 - 4 \
376 && (frame_info)->pc <= (frame_info)->frame) \
377 { next_addr = (frame_info)->frame; \
378 pc = (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM * 4 - 8*12 - 4; }\
379 else \
380 { pc = get_pc_function_start ((frame_info)->pc); \
381 /* Verify we have a link a6 instruction next; \
382 if not we lose. If we win, find the address above the saved \
383 regs using the amount of storage from the link instruction. */\
384 if (044016 == read_memory_integer (pc, 2)) \
385 next_addr = (frame_info)->frame + read_memory_integer (pc += 2, 4), pc+=4; \
386 else if (047126 == read_memory_integer (pc, 2)) \
387 next_addr = (frame_info)->frame + read_memory_integer (pc += 2, 2), pc+=2; \
388 else goto lose; \
389 /* If have an addal #-n, sp next, adjust next_addr. */ \
390 if ((0177777 & read_memory_integer (pc, 2)) == 0157774) \
391 next_addr += read_memory_integer (pc += 2, 4), pc += 4; \
392 } \
393 /* next should be a moveml to (sp) or -(sp) or a movl r,-(sp) */ \
394 regmask = read_memory_integer (pc + 2, 2); \
395 /* But before that can come an fmovem. Check for it. */ \
396 nextinsn = 0xffff & read_memory_integer (pc, 2); \
397 if (0xf227 == nextinsn \
398 && (regmask & 0xff00) == 0xe000) \
399 { pc += 4; /* Regmask's low bit is for register fp7, the first pushed */ \
400 for (regnum = FP0_REGNUM + 7; regnum >= FP0_REGNUM; regnum--, regmask >>= 1) \
401 if (regmask & 1) \
402 (frame_saved_regs).regs[regnum] = (next_addr -= 12); \
403 regmask = read_memory_integer (pc + 2, 2); } \
404 if (0044327 == read_memory_integer (pc, 2)) \
405 { pc += 4; /* Regmask's low bit is for register 0, the first written */ \
406 for (regnum = 0; regnum < 16; regnum++, regmask >>= 1) \
407 if (regmask & 1) \
408 (frame_saved_regs).regs[regnum] = (next_addr += 4) - 4; } \
409 else if (0044347 == read_memory_integer (pc, 2)) \
410 { pc += 4; /* Regmask's low bit is for register 15, the first pushed */ \
411 for (regnum = 15; regnum >= 0; regnum--, regmask >>= 1) \
412 if (regmask & 1) \
413 (frame_saved_regs).regs[regnum] = (next_addr -= 4); } \
414 else if (0x2f00 == (0xfff0 & read_memory_integer (pc, 2))) \
415 { regnum = 0xf & read_memory_integer (pc, 2); pc += 2; \
416 (frame_saved_regs).regs[regnum] = (next_addr -= 4); } \
417 /* fmovemx to index of sp may follow. */ \
418 regmask = read_memory_integer (pc + 2, 2); \
419 nextinsn = 0xffff & read_memory_integer (pc, 2); \
420 if (0xf236 == nextinsn \
421 && (regmask & 0xff00) == 0xf000) \
422 { pc += 10; /* Regmask's low bit is for register fp0, the first written */ \
423 for (regnum = FP0_REGNUM + 7; regnum >= FP0_REGNUM; regnum--, regmask >>= 1) \
424 if (regmask & 1) \
425 (frame_saved_regs).regs[regnum] = (next_addr += 12) - 12; \
426 regmask = read_memory_integer (pc + 2, 2); } \
427 /* clrw -(sp); movw ccr,-(sp) may follow. */ \
428 if (0x426742e7 == read_memory_integer (pc, 4)) \
429 (frame_saved_regs).regs[PS_REGNUM] = (next_addr -= 4); \
430 lose: ; \
431 (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 8; \
432 (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame; \
433 (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 4; \
434}
435#else /* no 68881. */
436#define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
437{ register int regnum; \
438 register int regmask; \
439 register CORE_ADDR next_addr; \
440 register CORE_ADDR pc; \
441 bzero (&frame_saved_regs, sizeof frame_saved_regs); \
442 if ((frame_info)->pc >= (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM*4 - 4 \
443 && (frame_info)->pc <= (frame_info)->frame) \
444 { next_addr = (frame_info)->frame; \
445 pc = (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM * 4 - 4; }\
446 else \
447 { pc = get_pc_function_start ((frame_info)->pc); \
448 /* Verify we have a link a6 instruction next; \
449 if not we lose. If we win, find the address above the saved \
450 regs using the amount of storage from the link instruction. */\
451 if (044016 == read_memory_integer (pc, 2)) \
452 next_addr = (frame_info)->frame + read_memory_integer (pc += 2, 4), pc+=4; \
453 else if (047126 == read_memory_integer (pc, 2)) \
454 next_addr = (frame_info)->frame + read_memory_integer (pc += 2, 2), pc+=2; \
455 else goto lose; \
456 /* If have an addal #-n, sp next, adjust next_addr. */ \
457 if ((0177777 & read_memory_integer (pc, 2)) == 0157774) \
458 next_addr += read_memory_integer (pc += 2, 4), pc += 4; \
459 } \
460 /* next should be a moveml to (sp) or -(sp) or a movl r,-(sp) */ \
461 regmask = read_memory_integer (pc + 2, 2); \
462 if (0044327 == read_memory_integer (pc, 2)) \
463 { pc += 4; /* Regmask's low bit is for register 0, the first written */ \
464 for (regnum = 0; regnum < 16; regnum++, regmask >>= 1) \
465 if (regmask & 1) \
466 (frame_saved_regs).regs[regnum] = (next_addr += 4) - 4; } \
467 else if (0044347 == read_memory_integer (pc, 2)) \
468 { pc += 4; /* Regmask's low bit is for register 15, the first pushed */ \
469 for (regnum = 15; regnum >= 0; regnum--, regmask >>= 1) \
470 if (regmask & 1) \
471 (frame_saved_regs).regs[regnum] = (next_addr -= 4); } \
472 else if (0x2f00 == 0xfff0 & read_memory_integer (pc, 2)) \
473 { regnum = 0xf & read_memory_integer (pc, 2); pc += 2; \
474 (frame_saved_regs).regs[regnum] = (next_addr -= 4); } \
475 /* clrw -(sp); movw ccr,-(sp) may follow. */ \
476 if (0x426742e7 == read_memory_integer (pc, 4)) \
477 (frame_saved_regs).regs[PS_REGNUM] = (next_addr -= 4); \
478 lose: ; \
479 (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 8; \
480 (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame; \
481 (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 4; \
482}
483#endif /* no 68881. */
484#endif /* no FIND_FRAME_SAVED_REGS. */
485
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486\f
487/* Things needed for making the inferior call functions.
488 It seems like every m68k based machine has almost identical definitions
489 in the individual machine's configuration files. Most other cpu types
490 (mips, i386, etc) have routines in their *-tdep.c files to handle this
491 for most configurations. The m68k family should be able to do this as
492 well. These macros can still be overridden when necessary. */
493
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FF
494/* The CALL_DUMMY macro is the sequence of instructions, as disassembled
495 by gdb itself:
496
497 fmovemx fp0-fp7,sp@- 0xf227 0xe0ff
498 moveml d0-a5,sp@- 0x48e7 0xfffc
499 clrw sp@- 0x4267
500 movew ccr,sp@- 0x42e7
501
502 /..* The arguments are pushed at this point by GDB;
dcd15e5e
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503 no code is needed in the dummy for this.
504 The CALL_DUMMY_START_OFFSET gives the position of
505 the following jsr instruction. *../
dcd15e5e 506
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507 jsr @#0x32323232 0x4eb9 0x3232 0x3232
508 addal #0x69696969,sp 0xdffc 0x6969 0x6969
509 trap #<your BPT_VECTOR number here> 0x4e4?
510 nop 0x4e71
511
512 Note this is CALL_DUMMY_LENGTH bytes (28 for the above example).
513 We actually start executing at the jsr, since the pushing of the
514 registers is done by PUSH_DUMMY_FRAME. If this were real code,
515 the arguments for the function called by the jsr would be pushed
516 between the moveml and the jsr, and we could allow it to execute through.
517 But the arguments have to be pushed by GDB after the PUSH_DUMMY_FRAME is
518 done, and we cannot allow the moveml to push the registers again lest
519 they be taken for the arguments. */
520
521#if defined (HAVE_68881)
522
523#define CALL_DUMMY {0xf227e0ff, 0x48e7fffc, 0x426742e7, 0x4eb93232, 0x3232dffc, 0x69696969, (0x4e404e71 | (BPT_VECTOR << 16))}
524#define CALL_DUMMY_LENGTH 28 /* Size of CALL_DUMMY */
525#define CALL_DUMMY_START_OFFSET 12 /* Offset to jsr instruction*/
526
527#else
dcd15e5e 528
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529#define CALL_DUMMY {0x48e7fffc, 0x426742e7, 0x4eb93232, 0x3232dffc, 0x69696969, (0x4e404e71 | (BPT_VECTOR << 16))}
530#define CALL_DUMMY_LENGTH 24 /* Size of CALL_DUMMY */
531#define CALL_DUMMY_START_OFFSET 8 /* Offset to jsr instruction*/
dcd15e5e 532
84d82b1c 533#endif /* HAVE_68881 */
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534
535/* Insert the specified number of args and function address
536 into a call sequence of the above form stored at DUMMYNAME. */
537
538#define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p) \
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539{ *(int *)((char *) dummyname + CALL_DUMMY_START_OFFSET + 2) = fun; \
540 *(int *)((char *) dummyname + CALL_DUMMY_START_OFFSET + 8) = nargs * 4; }
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541
542/* Push an empty stack frame, to record the current PC, etc. */
543
544#define PUSH_DUMMY_FRAME { m68k_push_dummy_frame (); }
545
546/* Discard from the stack the innermost frame, restoring all registers. */
547
84d82b1c 548#define POP_FRAME { m68k_pop_frame (); }
dcd15e5e 549
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