Commit | Line | Data |
---|---|---|
5076de82 FF |
1 | /* Definitions to make GDB run on a vax under 4.2bsd. |
2 | Copyright 1986, 1987, 1989, 1991, 1993 Free Software Foundation, Inc. | |
3 | ||
4 | This file is part of GDB. | |
5 | ||
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. | |
10 | ||
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. | |
15 | ||
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 | |
6c9638b4 | 18 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
5076de82 | 19 | |
5076de82 FF |
20 | |
21 | #define TARGET_BYTE_ORDER LITTLE_ENDIAN | |
22 | ||
23 | /* Offset from address of function to start of its code. | |
24 | Zero on most machines. */ | |
25 | ||
26 | #define FUNCTION_START_OFFSET 2 | |
27 | ||
28 | /* Advance PC across any function entry prologue instructions | |
29 | to reach some "real" code. */ | |
30 | ||
31 | #define SKIP_PROLOGUE(pc) \ | |
32 | { register int op = (unsigned char) read_memory_integer (pc, 1); \ | |
33 | if (op == 0x11) pc += 2; /* skip brb */ \ | |
34 | if (op == 0x31) pc += 3; /* skip brw */ \ | |
35 | if (op == 0xC2 && \ | |
36 | ((unsigned char) read_memory_integer (pc+2, 1)) == 0x5E) \ | |
37 | pc += 3; /* skip subl2 */ \ | |
38 | if (op == 0x9E && \ | |
39 | ((unsigned char) read_memory_integer (pc+1, 1)) == 0xAE && \ | |
40 | ((unsigned char) read_memory_integer(pc+3, 1)) == 0x5E) \ | |
41 | pc += 4; /* skip movab */ \ | |
42 | if (op == 0x9E && \ | |
43 | ((unsigned char) read_memory_integer (pc+1, 1)) == 0xCE && \ | |
44 | ((unsigned char) read_memory_integer(pc+4, 1)) == 0x5E) \ | |
45 | pc += 5; /* skip movab */ \ | |
46 | if (op == 0x9E && \ | |
47 | ((unsigned char) read_memory_integer (pc+1, 1)) == 0xEE && \ | |
48 | ((unsigned char) read_memory_integer(pc+6, 1)) == 0x5E) \ | |
49 | pc += 7; /* skip movab */ \ | |
50 | } | |
51 | ||
52 | /* Immediately after a function call, return the saved pc. | |
53 | Can't always go through the frames for this because on some machines | |
54 | the new frame is not set up until the new function executes | |
55 | some instructions. */ | |
56 | ||
57 | #define SAVED_PC_AFTER_CALL(frame) FRAME_SAVED_PC(frame) | |
58 | ||
7b98a091 | 59 | #define TARGET_UPAGES 14 |
5076de82 FF |
60 | #define TARGET_NBPG 512 |
61 | #define STACK_END_ADDR (0x80000000 - (TARGET_UPAGES * TARGET_NBPG)) | |
62 | ||
63 | /* On the VAX, sigtramp is in the u area. Can't check the exact | |
64 | addresses because for cross-debugging we don't have VAX include | |
65 | files around. This should be close enough. */ | |
9391c997 FF |
66 | #define SIGTRAMP_START(pc) STACK_END_ADDR |
67 | #define SIGTRAMP_END(pc) 0x80000000 | |
5076de82 FF |
68 | |
69 | /* Stack grows downward. */ | |
70 | ||
71 | #define INNER_THAN < | |
72 | ||
73 | /* Sequence of bytes for breakpoint instruction. */ | |
74 | ||
75 | #define BREAKPOINT {3} | |
76 | ||
77 | /* Amount PC must be decremented by after a breakpoint. | |
78 | This is often the number of bytes in BREAKPOINT | |
79 | but not always. */ | |
80 | ||
81 | #define DECR_PC_AFTER_BREAK 0 | |
82 | ||
83 | /* Nonzero if instruction at PC is a return instruction. */ | |
84 | ||
85 | #define ABOUT_TO_RETURN(pc) (read_memory_integer (pc, 1) == 04) | |
86 | ||
87 | /* Return 1 if P points to an invalid floating point value. | |
88 | LEN is the length in bytes -- not relevant on the Vax. */ | |
89 | ||
90 | #define INVALID_FLOAT(p, len) ((*(short *) p & 0xff80) == 0x8000) | |
91 | ||
f4f0d174 JK |
92 | /* Say how long (ordinary) registers are. This is a piece of bogosity |
93 | used in push_word and a few other places; REGISTER_RAW_SIZE is the | |
94 | real way to know how big a register is. */ | |
5076de82 | 95 | |
f4f0d174 | 96 | #define REGISTER_SIZE 4 |
5076de82 FF |
97 | |
98 | /* Number of machine registers */ | |
99 | ||
100 | #define NUM_REGS 17 | |
101 | ||
102 | /* Initializer for an array of names of registers. | |
103 | There should be NUM_REGS strings in this initializer. */ | |
104 | ||
105 | #define REGISTER_NAMES {"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "ap", "fp", "sp", "pc", "ps"} | |
106 | ||
107 | /* Register numbers of various important registers. | |
108 | Note that some of these values are "real" register numbers, | |
109 | and correspond to the general registers of the machine, | |
110 | and some are "phony" register numbers which are too large | |
111 | to be actual register numbers as far as the user is concerned | |
112 | but do serve to get the desired values when passed to read_register. */ | |
113 | ||
114 | #define AP_REGNUM 12 | |
115 | #define FP_REGNUM 13 /* Contains address of executing stack frame */ | |
116 | #define SP_REGNUM 14 /* Contains address of top of stack */ | |
117 | #define PC_REGNUM 15 /* Contains program counter */ | |
118 | #define PS_REGNUM 16 /* Contains processor status */ | |
119 | ||
120 | /* Total amount of space needed to store our copies of the machine's | |
121 | register state, the array `registers'. */ | |
122 | #define REGISTER_BYTES (17*4) | |
123 | ||
124 | /* Index within `registers' of the first byte of the space for | |
125 | register N. */ | |
126 | ||
127 | #define REGISTER_BYTE(N) ((N) * 4) | |
128 | ||
129 | /* Number of bytes of storage in the actual machine representation | |
130 | for register N. On the vax, all regs are 4 bytes. */ | |
131 | ||
132 | #define REGISTER_RAW_SIZE(N) 4 | |
133 | ||
134 | /* Number of bytes of storage in the program's representation | |
135 | for register N. On the vax, all regs are 4 bytes. */ | |
136 | ||
137 | #define REGISTER_VIRTUAL_SIZE(N) 4 | |
138 | ||
139 | /* Largest value REGISTER_RAW_SIZE can have. */ | |
140 | ||
141 | #define MAX_REGISTER_RAW_SIZE 4 | |
142 | ||
143 | /* Largest value REGISTER_VIRTUAL_SIZE can have. */ | |
144 | ||
145 | #define MAX_REGISTER_VIRTUAL_SIZE 4 | |
146 | ||
5076de82 FF |
147 | /* Return the GDB type object for the "standard" data type |
148 | of data in register N. */ | |
149 | ||
150 | #define REGISTER_VIRTUAL_TYPE(N) builtin_type_int | |
151 | ||
152 | /* Store the address of the place in which to copy the structure the | |
153 | subroutine will return. This is called from call_function. */ | |
154 | ||
155 | #define STORE_STRUCT_RETURN(ADDR, SP) \ | |
156 | { write_register (1, (ADDR)); } | |
157 | ||
158 | /* Extract from an array REGBUF containing the (raw) register state | |
159 | a function return value of type TYPE, and copy that, in virtual format, | |
160 | into VALBUF. */ | |
161 | ||
162 | #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \ | |
ade40d31 | 163 | memcpy (VALBUF, REGBUF, TYPE_LENGTH (TYPE)) |
5076de82 FF |
164 | |
165 | /* Write into appropriate registers a function return value | |
166 | of type TYPE, given in virtual format. */ | |
167 | ||
168 | #define STORE_RETURN_VALUE(TYPE,VALBUF) \ | |
169 | write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE)) | |
170 | ||
171 | /* Extract from an array REGBUF containing the (raw) register state | |
172 | the address in which a function should return its structure value, | |
173 | as a CORE_ADDR (or an expression that can be used as one). */ | |
174 | ||
175 | #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF)) | |
176 | ||
177 | \f | |
178 | /* Describe the pointer in each stack frame to the previous stack frame | |
179 | (its caller). */ | |
180 | ||
181 | /* FRAME_CHAIN takes a frame's nominal address | |
182 | and produces the frame's chain-pointer. */ | |
183 | ||
184 | /* In the case of the Vax, the frame's nominal address is the FP value, | |
185 | and 12 bytes later comes the saved previous FP value as a 4-byte word. */ | |
186 | ||
187 | #define FRAME_CHAIN(thisframe) \ | |
188 | (!inside_entry_file ((thisframe)->pc) ? \ | |
189 | read_memory_integer ((thisframe)->frame + 12, 4) :\ | |
190 | 0) | |
191 | ||
192 | /* Define other aspects of the stack frame. */ | |
193 | ||
194 | /* A macro that tells us whether the function invocation represented | |
195 | by FI does not have a frame on the stack associated with it. If it | |
196 | does not, FRAMELESS is set to 1, else 0. */ | |
197 | /* On the vax, all functions have frames. */ | |
198 | #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) {(FRAMELESS) = 0;} | |
199 | ||
7b98a091 | 200 | /* Saved Pc. Get it from sigcontext if within sigtramp. */ |
5076de82 | 201 | |
7b98a091 PS |
202 | /* Offset to saved PC in sigcontext, from <sys/signal.h>. */ |
203 | #define SIGCONTEXT_PC_OFFSET 12 | |
204 | ||
205 | #define FRAME_SAVED_PC(FRAME) \ | |
206 | (((FRAME)->signal_handler_caller \ | |
207 | ? sigtramp_saved_pc (FRAME) \ | |
208 | : read_memory_integer ((FRAME)->frame + 16, 4)) \ | |
209 | ) | |
5076de82 FF |
210 | |
211 | /* Cannot find the AP register value directly from the FP value. Must | |
212 | find it saved in the frame called by this one, or in the AP | |
213 | register for the innermost frame. However, there is no way to tell | |
214 | the difference between the innermost frame and a frame for which we | |
215 | just don't know the frame that it called (e.g. "info frame | |
216 | 0x7ffec789"). For the sake of argument suppose that the stack is | |
217 | somewhat trashed (which is one reason that "info frame" exists). | |
218 | So return 0 (indicating we don't know the address of | |
219 | the arglist) if we don't know what frame this frame calls. */ | |
220 | #define FRAME_ARGS_ADDRESS_CORRECT(fi) \ | |
23a8e291 JK |
221 | (((fi)->next \ |
222 | ? read_memory_integer ((fi)->next->frame + 8, 4) \ | |
5076de82 FF |
223 | : /* read_register (AP_REGNUM) */ 0)) |
224 | ||
225 | /* In most of GDB, getting the args address is too important to | |
226 | just say "I don't know". This is sometimes wrong for functions | |
227 | that aren't on top of the stack, but c'est la vie. */ | |
228 | #define FRAME_ARGS_ADDRESS(fi) \ | |
23a8e291 JK |
229 | (((fi)->next \ |
230 | ? read_memory_integer ((fi)->next->frame + 8, 4) \ | |
5076de82 FF |
231 | : read_register (AP_REGNUM) /* 0 */)) |
232 | ||
233 | #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame) | |
234 | ||
235 | /* Return number of args passed to a frame. | |
236 | Can return -1, meaning no way to tell. */ | |
237 | ||
238 | #define FRAME_NUM_ARGS(numargs, fi) \ | |
239 | { numargs = (0xff & read_memory_integer (FRAME_ARGS_ADDRESS (fi), 1)); } | |
240 | ||
241 | /* Return number of bytes at start of arglist that are not really args. */ | |
242 | ||
243 | #define FRAME_ARGS_SKIP 4 | |
244 | ||
245 | /* Put here the code to store, into a struct frame_saved_regs, | |
246 | the addresses of the saved registers of frame described by FRAME_INFO. | |
247 | This includes special registers such as pc and fp saved in special | |
248 | ways in the stack frame. sp is even more special: | |
249 | the address we return for it IS the sp for the next frame. */ | |
250 | ||
251 | #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \ | |
252 | { register int regnum; \ | |
253 | register int regmask = read_memory_integer ((frame_info)->frame+4, 4) >> 16; \ | |
254 | register CORE_ADDR next_addr; \ | |
4ed97c9a | 255 | memset (&frame_saved_regs, '\0', sizeof frame_saved_regs); \ |
5076de82 FF |
256 | next_addr = (frame_info)->frame + 16; \ |
257 | /* Regmask's low bit is for register 0, \ | |
258 | which is the first one that would be pushed. */ \ | |
259 | for (regnum = 0; regnum < 12; regnum++, regmask >>= 1) \ | |
260 | (frame_saved_regs).regs[regnum] = (regmask & 1) ? (next_addr += 4) : 0; \ | |
261 | (frame_saved_regs).regs[SP_REGNUM] = next_addr + 4; \ | |
262 | if (read_memory_integer ((frame_info)->frame + 4, 4) & 0x20000000) \ | |
263 | (frame_saved_regs).regs[SP_REGNUM] += 4 + 4 * read_memory_integer (next_addr + 4, 4); \ | |
264 | (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 16; \ | |
265 | (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame + 12; \ | |
266 | (frame_saved_regs).regs[AP_REGNUM] = (frame_info)->frame + 8; \ | |
267 | (frame_saved_regs).regs[PS_REGNUM] = (frame_info)->frame + 4; \ | |
268 | } | |
269 | \f | |
270 | /* Things needed for making the inferior call functions. */ | |
271 | ||
272 | /* Push an empty stack frame, to record the current PC, etc. */ | |
273 | ||
274 | #define PUSH_DUMMY_FRAME \ | |
275 | { register CORE_ADDR sp = read_register (SP_REGNUM);\ | |
276 | register int regnum; \ | |
277 | sp = push_word (sp, 0); /* arglist */ \ | |
278 | for (regnum = 11; regnum >= 0; regnum--) \ | |
279 | sp = push_word (sp, read_register (regnum)); \ | |
280 | sp = push_word (sp, read_register (PC_REGNUM)); \ | |
281 | sp = push_word (sp, read_register (FP_REGNUM)); \ | |
282 | sp = push_word (sp, read_register (AP_REGNUM)); \ | |
283 | sp = push_word (sp, (read_register (PS_REGNUM) & 0xffef) \ | |
284 | + 0x2fff0000); \ | |
285 | sp = push_word (sp, 0); \ | |
286 | write_register (SP_REGNUM, sp); \ | |
287 | write_register (FP_REGNUM, sp); \ | |
288 | write_register (AP_REGNUM, sp + 17 * sizeof (int)); } | |
289 | ||
290 | /* Discard from the stack the innermost frame, restoring all registers. */ | |
291 | ||
292 | #define POP_FRAME \ | |
293 | { register CORE_ADDR fp = read_register (FP_REGNUM); \ | |
294 | register int regnum; \ | |
295 | register int regmask = read_memory_integer (fp + 4, 4); \ | |
296 | write_register (PS_REGNUM, \ | |
297 | (regmask & 0xffff) \ | |
298 | | (read_register (PS_REGNUM) & 0xffff0000)); \ | |
299 | write_register (PC_REGNUM, read_memory_integer (fp + 16, 4)); \ | |
300 | write_register (FP_REGNUM, read_memory_integer (fp + 12, 4)); \ | |
301 | write_register (AP_REGNUM, read_memory_integer (fp + 8, 4)); \ | |
302 | fp += 16; \ | |
303 | for (regnum = 0; regnum < 12; regnum++) \ | |
304 | if (regmask & (0x10000 << regnum)) \ | |
305 | write_register (regnum, read_memory_integer (fp += 4, 4)); \ | |
306 | fp = fp + 4 + ((regmask >> 30) & 3); \ | |
307 | if (regmask & 0x20000000) \ | |
308 | { regnum = read_memory_integer (fp, 4); \ | |
309 | fp += (regnum + 1) * 4; } \ | |
310 | write_register (SP_REGNUM, fp); \ | |
311 | flush_cached_frames (); \ | |
16726dd1 | 312 | } |
5076de82 FF |
313 | |
314 | /* This sequence of words is the instructions | |
315 | calls #69, @#32323232 | |
316 | bpt | |
317 | Note this is 8 bytes. */ | |
318 | ||
319 | #define CALL_DUMMY {0x329f69fb, 0x03323232} | |
320 | ||
321 | #define CALL_DUMMY_START_OFFSET 0 /* Start execution at beginning of dummy */ | |
322 | ||
f0d2557c PS |
323 | #define CALL_DUMMY_BREAKPOINT_OFFSET 7 |
324 | ||
5076de82 FF |
325 | /* Insert the specified number of args and function address |
326 | into a call sequence of the above form stored at DUMMYNAME. */ | |
327 | ||
328 | #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p) \ | |
329 | { *((char *) dummyname + 1) = nargs; \ | |
330 | *(int *)((char *) dummyname + 3) = fun; } | |
486c47b9 PS |
331 | |
332 | /* If vax pcc says CHAR or SHORT, it provides the correct address. */ | |
333 | ||
334 | #define BELIEVE_PCC_PROMOTION 1 |