1 /* Definitions to make GDB run on a vax under 4.2bsd.
2 Copyright 1986, 1987, 1989, 1991, 1993 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 #define TARGET_BYTE_ORDER LITTLE_ENDIAN
23 /* Offset from address of function to start of its code.
24 Zero on most machines. */
26 #define FUNCTION_START_OFFSET 2
28 /* Advance PC across any function entry prologue instructions
29 to reach some "real" code. */
31 extern CORE_ADDR vax_skip_prologue
PARAMS ((CORE_ADDR
));
32 #define SKIP_PROLOGUE(pc) (vax_skip_prologue (pc))
34 /* Immediately after a function call, return the saved pc.
35 Can't always go through the frames for this because on some machines
36 the new frame is not set up until the new function executes
39 #define SAVED_PC_AFTER_CALL(frame) FRAME_SAVED_PC(frame)
41 #define TARGET_UPAGES 14
42 #define TARGET_NBPG 512
43 #define STACK_END_ADDR (0x80000000 - (TARGET_UPAGES * TARGET_NBPG))
45 /* On the VAX, sigtramp is in the u area. Can't check the exact
46 addresses because for cross-debugging we don't have VAX include
47 files around. This should be close enough. */
48 #define SIGTRAMP_START(pc) STACK_END_ADDR
49 #define SIGTRAMP_END(pc) 0x80000000
51 /* Stack grows downward. */
53 #define INNER_THAN(lhs,rhs) ((lhs) < (rhs))
55 /* Sequence of bytes for breakpoint instruction. */
57 #define BREAKPOINT {3}
59 /* Amount PC must be decremented by after a breakpoint.
60 This is often the number of bytes in BREAKPOINT
63 #define DECR_PC_AFTER_BREAK 0
65 /* Return 1 if P points to an invalid floating point value.
66 LEN is the length in bytes -- not relevant on the Vax. */
68 #define INVALID_FLOAT(p, len) ((*(short *) p & 0xff80) == 0x8000)
70 /* Say how long (ordinary) registers are. This is a piece of bogosity
71 used in push_word and a few other places; REGISTER_RAW_SIZE is the
72 real way to know how big a register is. */
74 #define REGISTER_SIZE 4
76 /* Number of machine registers */
80 /* Initializer for an array of names of registers.
81 There should be NUM_REGS strings in this initializer. */
83 #define REGISTER_NAMES {"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "ap", "fp", "sp", "pc", "ps"}
85 /* Register numbers of various important registers.
86 Note that some of these values are "real" register numbers,
87 and correspond to the general registers of the machine,
88 and some are "phony" register numbers which are too large
89 to be actual register numbers as far as the user is concerned
90 but do serve to get the desired values when passed to read_register. */
93 #define FP_REGNUM 13 /* Contains address of executing stack frame */
94 #define SP_REGNUM 14 /* Contains address of top of stack */
95 #define PC_REGNUM 15 /* Contains program counter */
96 #define PS_REGNUM 16 /* Contains processor status */
98 /* Total amount of space needed to store our copies of the machine's
99 register state, the array `registers'. */
100 #define REGISTER_BYTES (17*4)
102 /* Index within `registers' of the first byte of the space for
105 #define REGISTER_BYTE(N) ((N) * 4)
107 /* Number of bytes of storage in the actual machine representation
108 for register N. On the vax, all regs are 4 bytes. */
110 #define REGISTER_RAW_SIZE(N) 4
112 /* Number of bytes of storage in the program's representation
113 for register N. On the vax, all regs are 4 bytes. */
115 #define REGISTER_VIRTUAL_SIZE(N) 4
117 /* Largest value REGISTER_RAW_SIZE can have. */
119 #define MAX_REGISTER_RAW_SIZE 4
121 /* Largest value REGISTER_VIRTUAL_SIZE can have. */
123 #define MAX_REGISTER_VIRTUAL_SIZE 4
125 /* Return the GDB type object for the "standard" data type
126 of data in register N. */
128 #define REGISTER_VIRTUAL_TYPE(N) builtin_type_int
130 /* Store the address of the place in which to copy the structure the
131 subroutine will return. This is called from call_function. */
133 #define STORE_STRUCT_RETURN(ADDR, SP) \
134 { write_register (1, (ADDR)); }
136 /* Extract from an array REGBUF containing the (raw) register state
137 a function return value of type TYPE, and copy that, in virtual format,
140 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
141 memcpy (VALBUF, REGBUF, TYPE_LENGTH (TYPE))
143 /* Write into appropriate registers a function return value
144 of type TYPE, given in virtual format. */
146 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
147 write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
149 /* Extract from an array REGBUF containing the (raw) register state
150 the address in which a function should return its structure value,
151 as a CORE_ADDR (or an expression that can be used as one). */
153 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF))
156 /* Describe the pointer in each stack frame to the previous stack frame
159 /* FRAME_CHAIN takes a frame's nominal address
160 and produces the frame's chain-pointer. */
162 /* In the case of the Vax, the frame's nominal address is the FP value,
163 and 12 bytes later comes the saved previous FP value as a 4-byte word. */
165 #define FRAME_CHAIN(thisframe) \
166 (!inside_entry_file ((thisframe)->pc) ? \
167 read_memory_integer ((thisframe)->frame + 12, 4) :\
170 /* Define other aspects of the stack frame. */
172 /* A macro that tells us whether the function invocation represented
173 by FI does not have a frame on the stack associated with it. If it
174 does not, FRAMELESS is set to 1, else 0. */
175 /* On the vax, all functions have frames. */
176 #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) {(FRAMELESS) = 0;}
178 /* Saved Pc. Get it from sigcontext if within sigtramp. */
180 /* Offset to saved PC in sigcontext, from <sys/signal.h>. */
181 #define SIGCONTEXT_PC_OFFSET 12
183 #define FRAME_SAVED_PC(FRAME) \
184 (((FRAME)->signal_handler_caller \
185 ? sigtramp_saved_pc (FRAME) \
186 : read_memory_integer ((FRAME)->frame + 16, 4)) \
189 /* Cannot find the AP register value directly from the FP value. Must
190 find it saved in the frame called by this one, or in the AP
191 register for the innermost frame. However, there is no way to tell
192 the difference between the innermost frame and a frame for which we
193 just don't know the frame that it called (e.g. "info frame
194 0x7ffec789"). For the sake of argument suppose that the stack is
195 somewhat trashed (which is one reason that "info frame" exists).
196 So return 0 (indicating we don't know the address of
197 the arglist) if we don't know what frame this frame calls. */
198 #define FRAME_ARGS_ADDRESS_CORRECT(fi) \
200 ? read_memory_integer ((fi)->next->frame + 8, 4) \
201 : /* read_register (AP_REGNUM) */ 0))
203 /* In most of GDB, getting the args address is too important to
204 just say "I don't know". This is sometimes wrong for functions
205 that aren't on top of the stack, but c'est la vie. */
206 #define FRAME_ARGS_ADDRESS(fi) \
208 ? read_memory_integer ((fi)->next->frame + 8, 4) \
209 : read_register (AP_REGNUM) /* 0 */))
211 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
213 /* Return number of args passed to a frame.
214 Can return -1, meaning no way to tell. */
216 #define FRAME_NUM_ARGS(numargs, fi) \
217 { numargs = (0xff & read_memory_integer (FRAME_ARGS_ADDRESS (fi), 1)); }
219 /* Return number of bytes at start of arglist that are not really args. */
221 #define FRAME_ARGS_SKIP 4
223 /* Put here the code to store, into a struct frame_saved_regs,
224 the addresses of the saved registers of frame described by FRAME_INFO.
225 This includes special registers such as pc and fp saved in special
226 ways in the stack frame. sp is even more special:
227 the address we return for it IS the sp for the next frame. */
229 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
230 { register int regnum; \
231 register int regmask = read_memory_integer ((frame_info)->frame+4, 4) >> 16; \
232 register CORE_ADDR next_addr; \
233 memset (&frame_saved_regs, '\0', sizeof frame_saved_regs); \
234 next_addr = (frame_info)->frame + 16; \
235 /* Regmask's low bit is for register 0, \
236 which is the first one that would be pushed. */ \
237 for (regnum = 0; regnum < 12; regnum++, regmask >>= 1) \
238 (frame_saved_regs).regs[regnum] = (regmask & 1) ? (next_addr += 4) : 0; \
239 (frame_saved_regs).regs[SP_REGNUM] = next_addr + 4; \
240 if (read_memory_integer ((frame_info)->frame + 4, 4) & 0x20000000) \
241 (frame_saved_regs).regs[SP_REGNUM] += 4 + 4 * read_memory_integer (next_addr + 4, 4); \
242 (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 16; \
243 (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame + 12; \
244 (frame_saved_regs).regs[AP_REGNUM] = (frame_info)->frame + 8; \
245 (frame_saved_regs).regs[PS_REGNUM] = (frame_info)->frame + 4; \
248 /* Things needed for making the inferior call functions. */
250 /* Push an empty stack frame, to record the current PC, etc. */
252 #define PUSH_DUMMY_FRAME \
253 { register CORE_ADDR sp = read_register (SP_REGNUM);\
254 register int regnum; \
255 sp = push_word (sp, 0); /* arglist */ \
256 for (regnum = 11; regnum >= 0; regnum--) \
257 sp = push_word (sp, read_register (regnum)); \
258 sp = push_word (sp, read_register (PC_REGNUM)); \
259 sp = push_word (sp, read_register (FP_REGNUM)); \
260 sp = push_word (sp, read_register (AP_REGNUM)); \
261 sp = push_word (sp, (read_register (PS_REGNUM) & 0xffef) \
263 sp = push_word (sp, 0); \
264 write_register (SP_REGNUM, sp); \
265 write_register (FP_REGNUM, sp); \
266 write_register (AP_REGNUM, sp + 17 * sizeof (int)); }
268 /* Discard from the stack the innermost frame, restoring all registers. */
271 { register CORE_ADDR fp = read_register (FP_REGNUM); \
272 register int regnum; \
273 register int regmask = read_memory_integer (fp + 4, 4); \
274 write_register (PS_REGNUM, \
276 | (read_register (PS_REGNUM) & 0xffff0000)); \
277 write_register (PC_REGNUM, read_memory_integer (fp + 16, 4)); \
278 write_register (FP_REGNUM, read_memory_integer (fp + 12, 4)); \
279 write_register (AP_REGNUM, read_memory_integer (fp + 8, 4)); \
281 for (regnum = 0; regnum < 12; regnum++) \
282 if (regmask & (0x10000 << regnum)) \
283 write_register (regnum, read_memory_integer (fp += 4, 4)); \
284 fp = fp + 4 + ((regmask >> 30) & 3); \
285 if (regmask & 0x20000000) \
286 { regnum = read_memory_integer (fp, 4); \
287 fp += (regnum + 1) * 4; } \
288 write_register (SP_REGNUM, fp); \
289 flush_cached_frames (); \
292 /* This sequence of words is the instructions
293 calls #69, @#32323232
295 Note this is 8 bytes. */
297 #define CALL_DUMMY {0x329f69fb, 0x03323232}
299 #define CALL_DUMMY_START_OFFSET 0 /* Start execution at beginning of dummy */
301 #define CALL_DUMMY_BREAKPOINT_OFFSET 7
303 /* Insert the specified number of args and function address
304 into a call sequence of the above form stored at DUMMYNAME. */
306 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p) \
307 { *((char *) dummyname + 1) = nargs; \
308 *(int *)((char *) dummyname + 3) = fun; }
310 /* If vax pcc says CHAR or SHORT, it provides the correct address. */
312 #define BELIEVE_PCC_PROMOTION 1