Commit | Line | Data |
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41abdfbd | 1 | /* Parameters for target execution on an RS6000, for GDB, the GNU debugger. |
6edd74ae | 2 | Copyright 1986, 1987, 1989, 1991, 1992, 1993 Free Software Foundation, Inc. |
41abdfbd JG |
3 | Contributed by IBM Corporation. |
4 | ||
5 | This file is part of GDB. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 2 of the License, or | |
10 | (at your option) any later version. | |
11 | ||
12 | This program is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with this program; if not, write to the Free Software | |
19 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
20 | ||
21 | extern int symtab_relocated; | |
22 | ||
818de002 PB |
23 | /* Minimum possible text address in AIX */ |
24 | ||
25 | #define TEXT_SEGMENT_BASE 0x10000000 | |
26 | ||
27 | ||
41abdfbd JG |
28 | /* text addresses in a core file does not necessarily match to symbol table, |
29 | if symbol table relocation wasn't done yet. */ | |
30 | ||
31 | #define CORE_NEEDS_RELOCATION(PC) \ | |
2aefe6e4 JK |
32 | if (!symtab_relocated && !inferior_pid) \ |
33 | xcoff_relocate_core (); | |
34 | extern void xcoff_relocate_core PARAMS ((void)); | |
41abdfbd | 35 | |
1eeba686 PB |
36 | /* Load segment of a given pc value. */ |
37 | ||
38 | #define PC_LOAD_SEGMENT(PC) pc_load_segment_name(PC) | |
39 | ||
cdb1cc92 ILT |
40 | /* AIX cc seems to get this right. */ |
41 | ||
42 | #define BELIEVE_PCC_PROMOTION 1 | |
1eeba686 | 43 | |
41abdfbd JG |
44 | /* Conversion between a register number in stab string to actual register num. */ |
45 | ||
46 | #define STAB_REG_TO_REGNUM(value) (value) | |
47 | ||
48 | /* return true if a given `pc' value is in `call dummy' function. */ | |
49 | ||
50 | #define PC_IN_CALL_DUMMY(STOP_PC, STOP_SP, STOP_FRAME_ADDR) \ | |
51 | (STOP_SP < STOP_PC && STOP_PC < STACK_END_ADDR) | |
52 | ||
53 | /* For each symtab, we keep track of which BFD it came from. */ | |
54 | #define EXTRA_SYMTAB_INFO \ | |
55 | unsigned nonreloc:1; /* TRUE if non relocatable */ | |
56 | ||
57 | #define INIT_EXTRA_SYMTAB_INFO(symtab) \ | |
58 | symtab->nonreloc = 0; \ | |
59 | ||
60 | extern unsigned int text_start, data_start; | |
61 | extern int inferior_pid; | |
62 | extern char *corefile; | |
63 | ||
64 | /* setpgrp() messes up controling terminal. The other version of it | |
65 | requires libbsd.a. */ | |
66 | #define setpgrp(XX,YY) setpgid (XX, YY) | |
67 | ||
68 | /* We are missing register descriptions in the system header files. Sigh! */ | |
69 | ||
70 | struct regs { | |
6c6afbb9 PB |
71 | int gregs [32]; /* general purpose registers */ |
72 | int pc; /* program conter */ | |
73 | int ps; /* processor status, or machine state */ | |
41abdfbd JG |
74 | }; |
75 | ||
76 | struct fp_status { | |
6c6afbb9 | 77 | double fpregs [32]; /* floating GP registers */ |
41abdfbd JG |
78 | }; |
79 | ||
6c6afbb9 PB |
80 | |
81 | /* To be used by function_frame_info. */ | |
82 | ||
83 | struct aix_framedata { | |
84 | int offset; /* # of bytes in gpr's and fpr's are saved */ | |
85 | int saved_gpr; /* smallest # of saved gpr */ | |
86 | int saved_fpr; /* smallest # of saved fpr */ | |
87 | int alloca_reg; /* alloca register number (frame ptr) */ | |
88 | char frameless; /* true if frameless functions. */ | |
cdb1cc92 | 89 | char nosavedpc; /* true if pc not saved. */ |
6c6afbb9 PB |
90 | }; |
91 | ||
d6434f39 JG |
92 | void |
93 | function_frame_info PARAMS ((CORE_ADDR, struct aix_framedata *)); | |
6c6afbb9 | 94 | |
41abdfbd JG |
95 | /* Define the byte order of the machine. */ |
96 | ||
97 | #define TARGET_BYTE_ORDER BIG_ENDIAN | |
98 | ||
ba2c9027 PB |
99 | /* AIX's assembler doesn't grok dollar signs in identifiers. |
100 | So we use dots instead. This item must be coordinated with G++. */ | |
101 | #undef CPLUS_MARKER | |
102 | #define CPLUS_MARKER '.' | |
103 | ||
41abdfbd JG |
104 | /* Offset from address of function to start of its code. |
105 | Zero on most machines. */ | |
106 | ||
107 | #define FUNCTION_START_OFFSET 0 | |
108 | ||
109 | /* Advance PC across any function entry prologue instructions | |
110 | to reach some "real" code. */ | |
111 | ||
112 | #define SKIP_PROLOGUE(pc) pc = skip_prologue (pc) | |
113 | ||
114 | /* If PC is in some function-call trampoline code, return the PC | |
115 | where the function itself actually starts. If not, return NULL. */ | |
116 | ||
117 | #define SKIP_TRAMPOLINE_CODE(pc) skip_trampoline_code (pc) | |
118 | ||
119 | /* When a child process is just starting, we sneak in and relocate | |
120 | the symbol table (and other stuff) after the dynamic linker has | |
818de002 PB |
121 | figured out where they go. But we want to do this relocation just |
122 | once. */ | |
123 | ||
9b280a7f | 124 | extern int loadinfotextindex; |
818de002 | 125 | |
6730b139 | 126 | #define SOLIB_CREATE_INFERIOR_HOOK(PID) \ |
818de002 | 127 | do { \ |
9b280a7f JG |
128 | if (loadinfotextindex == 0) \ |
129 | xcoff_relocate_symtab (PID); \ | |
818de002 PB |
130 | } while (0) |
131 | ||
132 | ||
556f3d90 PB |
133 | /* Number of trap signals we need to skip over, once the inferior process |
134 | starts running. */ | |
1eeba686 PB |
135 | |
136 | #define START_INFERIOR_TRAPS_EXPECTED 2 | |
137 | ||
138 | /* AIX might return a sigtrap, with a "stop after load" status. It should | |
139 | be ignored by gdb, shouldn't be mixed up with breakpoint traps. */ | |
140 | ||
556f3d90 PB |
141 | /* Another little glitch in AIX is signal 0. I have no idea why wait(2) |
142 | returns with this status word. It looks harmless. */ | |
143 | ||
1eeba686 | 144 | #define SIGTRAP_STOP_AFTER_LOAD(W) \ |
556f3d90 PB |
145 | if ( (W) == 0x57c || (W) == 0x7f) { \ |
146 | if ((W)==0x57c && breakpoints_inserted) { \ | |
1eeba686 PB |
147 | mark_breakpoints_out (); \ |
148 | insert_breakpoints (); \ | |
149 | insert_step_breakpoint (); \ | |
150 | } \ | |
151 | resume (0, 0); \ | |
152 | continue; \ | |
153 | } | |
41abdfbd | 154 | |
9b280a7f | 155 | /* In xcoff, we cannot process line numbers when we see them. This is |
818de002 PB |
156 | mainly because we don't know the boundaries of the include files. So, |
157 | we postpone that, and then enter and sort(?) the whole line table at | |
158 | once, when we are closing the current symbol table in end_symtab(). */ | |
159 | ||
160 | #define PROCESS_LINENUMBER_HOOK() aix_process_linenos () | |
161 | ||
162 | ||
41abdfbd | 163 | /* When a target process or core-file has been attached, we sneak in |
818de002 PB |
164 | and figure out where the shared libraries have got to. In case there |
165 | is no inferior_process exists (e.g. bringing up a core file), we can't | |
166 | attemtp to relocate symbol table, since we don't have information about | |
167 | load segments. */ | |
41abdfbd | 168 | |
818de002 | 169 | #define SOLIB_ADD(a, b, c) \ |
9b280a7f | 170 | if (inferior_pid) xcoff_relocate_symtab (inferior_pid) |
41abdfbd JG |
171 | |
172 | /* Immediately after a function call, return the saved pc. | |
173 | Can't go through the frames for this because on some machines | |
174 | the new frame is not set up until the new function executes | |
175 | some instructions. */ | |
176 | ||
cdb1cc92 | 177 | #define SAVED_PC_AFTER_CALL(frame) read_register (LR_REGNUM) |
41abdfbd JG |
178 | |
179 | /* Address of end of stack space. */ | |
180 | ||
181 | #define STACK_END_ADDR 0x2ff80000 | |
182 | ||
183 | /* Stack grows downward. */ | |
184 | ||
185 | #define INNER_THAN < | |
186 | ||
187 | #if 0 | |
188 | /* No, we shouldn't use this. push_arguments() should leave stack in a | |
189 | proper alignment! */ | |
190 | /* Stack has strict alignment. */ | |
191 | ||
192 | #define STACK_ALIGN(ADDR) (((ADDR)+7)&-8) | |
193 | #endif | |
194 | ||
195 | /* This is how argumets pushed onto stack or passed in registers. */ | |
196 | ||
197 | #define PUSH_ARGUMENTS(nargs, args, sp, struct_return, struct_addr) \ | |
198 | sp = push_arguments(nargs, args, sp, struct_return, struct_addr) | |
199 | ||
200 | /* Sequence of bytes for breakpoint instruction. */ | |
201 | ||
202 | #define BREAKPOINT {0x7d, 0x82, 0x10, 0x08} | |
203 | ||
204 | /* Amount PC must be decremented by after a breakpoint. | |
205 | This is often the number of bytes in BREAKPOINT | |
206 | but not always. */ | |
207 | ||
208 | #define DECR_PC_AFTER_BREAK 0 | |
209 | ||
210 | /* Nonzero if instruction at PC is a return instruction. */ | |
211 | /* Allow any of the return instructions, including a trapv and a return | |
212 | from interrupt. */ | |
213 | ||
214 | #define ABOUT_TO_RETURN(pc) \ | |
215 | ((read_memory_integer (pc, 4) & 0xfe8007ff) == 0x4e800020) | |
216 | ||
217 | /* Return 1 if P points to an invalid floating point value. */ | |
218 | ||
219 | #define INVALID_FLOAT(p, len) 0 /* Just a first guess; not checked */ | |
220 | ||
221 | /* Largest integer type */ | |
222 | ||
223 | #define LONGEST long | |
224 | ||
225 | /* Name of the builtin type for the LONGEST type above. */ | |
226 | ||
227 | #define BUILTIN_TYPE_LONGEST builtin_type_long | |
228 | ||
229 | /* Say how long (ordinary) registers are. */ | |
230 | ||
231 | #define REGISTER_TYPE long | |
232 | ||
233 | /* Number of machine registers */ | |
234 | ||
235 | #define NUM_REGS 71 | |
236 | ||
237 | /* Initializer for an array of names of registers. | |
238 | There should be NUM_REGS strings in this initializer. */ | |
239 | ||
240 | #define REGISTER_NAMES \ | |
818de002 | 241 | {"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", \ |
41abdfbd JG |
242 | "r8", "r9", "r10","r11","r12","r13","r14","r15", \ |
243 | "r16","r17","r18","r19","r20","r21","r22","r23", \ | |
244 | "r24","r25","r26","r27","r28","r29","r30","r31", \ | |
245 | "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", \ | |
246 | "f8", "f9", "f10","f11","f12","f13","f14","f15", \ | |
247 | "f16","f17","f18","f19","f20","f21","f22","f23", \ | |
248 | "f24","f25","f26","f27","f28","f29","f30","f31", \ | |
249 | "pc", "ps", "cnd", "lr", "cnt", "xer", "mq" } | |
250 | ||
251 | /* Register numbers of various important registers. | |
252 | Note that some of these values are "real" register numbers, | |
253 | and correspond to the general registers of the machine, | |
254 | and some are "phony" register numbers which are too large | |
255 | to be actual register numbers as far as the user is concerned | |
256 | but do serve to get the desired values when passed to read_register. */ | |
257 | ||
258 | #define FP_REGNUM 1 /* Contains address of executing stack frame */ | |
259 | #define SP_REGNUM 1 /* Contains address of top of stack */ | |
260 | #define TOC_REGNUM 2 /* TOC register */ | |
261 | #define FP0_REGNUM 32 /* Floating point register 0 */ | |
818de002 PB |
262 | #define GP0_REGNUM 0 /* GPR register 0 */ |
263 | #define FP0_REGNUM 32 /* FPR (Floating point) register 0 */ | |
41abdfbd JG |
264 | #define FPLAST_REGNUM 63 /* Last floating point register */ |
265 | ||
266 | /* Special purpose registers... */ | |
267 | /* P.S. keep these in the same order as in /usr/mstsave.h `mstsave' structure, for | |
268 | easier processing */ | |
269 | ||
270 | #define PC_REGNUM 64 /* Program counter (instruction address %iar) */ | |
271 | #define PS_REGNUM 65 /* Processor (or machine) status (%msr) */ | |
272 | #define CR_REGNUM 66 /* Condition register */ | |
273 | #define LR_REGNUM 67 /* Link register */ | |
274 | #define CTR_REGNUM 68 /* Count register */ | |
275 | #define XER_REGNUM 69 /* Fixed point exception registers */ | |
276 | #define MQ_REGNUM 70 /* Multiply/quotient register */ | |
277 | ||
278 | #define FIRST_SP_REGNUM 64 /* first special register number */ | |
279 | #define LAST_SP_REGNUM 70 /* last special register number */ | |
280 | ||
281 | /* Total amount of space needed to store our copies of the machine's | |
282 | register state, the array `registers'. | |
283 | ||
284 | 32 4-byte gpr's | |
285 | 32 8-byte fpr's | |
286 | 7 4-byte special purpose registers, | |
287 | ||
288 | total 416 bytes. Keep some extra space for now, in case to add more. */ | |
289 | ||
290 | #define REGISTER_BYTES 420 | |
291 | ||
292 | ||
293 | /* Index within `registers' of the first byte of the space for | |
294 | register N. */ | |
295 | ||
296 | #define REGISTER_BYTE(N) \ | |
297 | ( \ | |
298 | ((N) > FPLAST_REGNUM) ? ((((N) - FPLAST_REGNUM -1) * 4) + 384)\ | |
299 | :((N) >= FP0_REGNUM) ? ((((N) - FP0_REGNUM) * 8) + 128) \ | |
300 | :((N) * 4) ) | |
301 | ||
302 | /* Number of bytes of storage in the actual machine representation | |
303 | for register N. */ | |
304 | /* Note that the unsigned cast here forces the result of the | |
305 | subtractiion to very high positive values if N < FP0_REGNUM */ | |
306 | ||
307 | #define REGISTER_RAW_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 32 ? 8 : 4) | |
308 | ||
309 | /* Number of bytes of storage in the program's representation | |
310 | for register N. On the RS6000, all regs are 4 bytes | |
311 | except the floating point regs which are 8-byte doubles. */ | |
312 | ||
313 | #define REGISTER_VIRTUAL_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 32 ? 8 : 4) | |
314 | ||
315 | /* Largest value REGISTER_RAW_SIZE can have. */ | |
316 | ||
317 | #define MAX_REGISTER_RAW_SIZE 8 | |
318 | ||
319 | /* Largest value REGISTER_VIRTUAL_SIZE can have. */ | |
320 | ||
321 | #define MAX_REGISTER_VIRTUAL_SIZE 8 | |
322 | ||
323 | /* convert a dbx stab register number (from `r' declaration) to a gdb REGNUM */ | |
324 | ||
325 | #define STAB_REG_TO_REGNUM(value) (value) | |
326 | ||
327 | /* Nonzero if register N requires conversion | |
328 | from raw format to virtual format. */ | |
329 | ||
330 | #define REGISTER_CONVERTIBLE(N) ((N) >= FP0_REGNUM && (N) <= FPLAST_REGNUM) | |
331 | ||
332 | /* Convert data from raw format for register REGNUM | |
333 | to virtual format for register REGNUM. */ | |
334 | ||
335 | #define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO) \ | |
336 | bcopy ((FROM), (TO), REGISTER_RAW_SIZE (REGNUM)) | |
337 | ||
338 | /* Convert data from virtual format for register REGNUM | |
339 | to raw format for register REGNUM. */ | |
340 | ||
341 | #define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO) \ | |
342 | bcopy ((FROM), (TO), REGISTER_RAW_SIZE (REGNUM)) | |
343 | ||
344 | /* Return the GDB type object for the "standard" data type | |
345 | of data in register N. */ | |
346 | ||
347 | #define REGISTER_VIRTUAL_TYPE(N) \ | |
348 | (((unsigned)(N) - FP0_REGNUM) < 32 ? builtin_type_double : builtin_type_int) | |
349 | ||
350 | /* Store the address of the place in which to copy the structure the | |
351 | subroutine will return. This is called from call_function. */ | |
352 | /* in RS6000, struct return addresses are passed as an extra parameter in r3. | |
353 | In function return, callee is not responsible of returning this address back. | |
354 | Since gdb needs to find it, we will store in a designated variable | |
355 | `rs6000_struct_return_address'. */ | |
356 | ||
357 | extern unsigned int rs6000_struct_return_address; | |
358 | ||
359 | #define STORE_STRUCT_RETURN(ADDR, SP) \ | |
360 | { write_register (3, (ADDR)); \ | |
361 | rs6000_struct_return_address = (unsigned int)(ADDR); } | |
362 | ||
363 | /* Extract from an array REGBUF containing the (raw) register state | |
364 | a function return value of type TYPE, and copy that, in virtual format, | |
365 | into VALBUF. */ | |
366 | ||
367 | /* #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \ | |
368 | bcopy (REGBUF, VALBUF, TYPE_LENGTH (TYPE)) */ | |
369 | ||
370 | #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \ | |
371 | extract_return_value(TYPE,REGBUF,VALBUF) | |
372 | ||
373 | /* Write into appropriate registers a function return value | |
374 | of type TYPE, given in virtual format. */ | |
375 | ||
376 | #define STORE_RETURN_VALUE(TYPE,VALBUF) \ | |
818de002 PB |
377 | { \ |
378 | if (TYPE_CODE (TYPE) == TYPE_CODE_FLT) \ | |
379 | \ | |
380 | /* Floating point values are returned starting from FPR1 and up. \ | |
381 | Say a double_double_double type could be returned in \ | |
382 | FPR1/FPR2/FPR3 triple. */ \ | |
383 | \ | |
384 | write_register_bytes (REGISTER_BYTE (FP0_REGNUM+1), (VALBUF), \ | |
385 | TYPE_LENGTH (TYPE)); \ | |
386 | else \ | |
387 | /* Everything else is returned in GPR3 and up. */ \ | |
388 | write_register_bytes (REGISTER_BYTE (GP0_REGNUM+3), (VALBUF), \ | |
389 | TYPE_LENGTH (TYPE)); \ | |
390 | } | |
391 | ||
41abdfbd JG |
392 | |
393 | /* Extract from an array REGBUF containing the (raw) register state | |
394 | the address in which a function should return its structure value, | |
395 | as a CORE_ADDR (or an expression that can be used as one). */ | |
396 | ||
397 | #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) rs6000_struct_return_address | |
41abdfbd JG |
398 | \f |
399 | /* Describe the pointer in each stack frame to the previous stack frame | |
400 | (its caller). */ | |
401 | ||
402 | /* FRAME_CHAIN takes a frame's nominal address | |
5e2e79f8 | 403 | and produces the frame's chain-pointer. */ |
41abdfbd JG |
404 | |
405 | /* In the case of the RS6000, the frame's nominal address | |
406 | is the address of a 4-byte word containing the calling frame's address. */ | |
407 | ||
408 | #define FRAME_CHAIN(thisframe) \ | |
5e2e79f8 | 409 | (!inside_entry_file ((thisframe)->pc) ? \ |
41abdfbd JG |
410 | read_memory_integer ((thisframe)->frame, 4) :\ |
411 | 0) | |
412 | ||
41abdfbd JG |
413 | /* Define other aspects of the stack frame. */ |
414 | ||
415 | /* A macro that tells us whether the function invocation represented | |
416 | by FI does not have a frame on the stack associated with it. If it | |
417 | does not, FRAMELESS is set to 1, else 0. */ | |
418 | ||
419 | #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \ | |
cdb1cc92 | 420 | FRAMELESS = frameless_function_invocation (FI, 0) |
41abdfbd | 421 | |
6c6afbb9 PB |
422 | /* Functions calling alloca() change the value of the stack pointer. We |
423 | need to use initial stack pointer (which is saved in r31 by gcc) in | |
424 | such cases. If a compiler emits traceback table, then we should use the | |
425 | alloca register specified in traceback table. FIXME. */ | |
426 | /* Also, it is a good idea to cache information about frame's saved registers | |
427 | in the frame structure to speed things up. See tm-m88k.h. FIXME. */ | |
428 | ||
429 | #define EXTRA_FRAME_INFO \ | |
430 | CORE_ADDR initial_sp; /* initial stack pointer. */ \ | |
431 | struct frame_saved_regs *cache_fsr; /* saved registers */ | |
432 | ||
cdb1cc92 ILT |
433 | /* Frameless function invocation in IBM RS/6000 is sometimes |
434 | half-done. It perfectly sets up a new frame, e.g. a new frame (in | |
435 | fact stack) pointer, etc, but it doesn't save the %pc. We call | |
436 | frameless_function_invocation to tell us how to get the %pc. */ | |
41abdfbd JG |
437 | |
438 | #define INIT_EXTRA_FRAME_INFO(fromleaf, fi) \ | |
6c6afbb9 | 439 | fi->initial_sp = 0; \ |
1eeba686 | 440 | fi->cache_fsr = 0; |
41abdfbd | 441 | |
cdb1cc92 ILT |
442 | #define FRAME_SAVED_PC(FRAME) \ |
443 | (frameless_function_invocation (FRAME, 1) \ | |
444 | ? SAVED_PC_AFTER_CALL (FRAME) \ | |
445 | : read_memory_integer (read_memory_integer ((FRAME)->frame, 4)+8, 4)) | |
41abdfbd | 446 | |
6c6afbb9 PB |
447 | #define FRAME_ARGS_ADDRESS(FI) \ |
448 | (((struct frame_info*)(FI))->initial_sp ? \ | |
449 | ((struct frame_info*)(FI))->initial_sp : \ | |
450 | frame_initial_stack_address (FI)) | |
451 | ||
452 | #define FRAME_LOCALS_ADDRESS(FI) FRAME_ARGS_ADDRESS(FI) | |
41abdfbd | 453 | |
41abdfbd JG |
454 | |
455 | /* Set VAL to the number of args passed to frame described by FI. | |
456 | Can set VAL to -1, meaning no way to tell. */ | |
457 | ||
458 | /* We can't tell how many args there are | |
459 | now that the C compiler delays popping them. */ | |
460 | ||
461 | #define FRAME_NUM_ARGS(val,fi) (val = -1) | |
462 | ||
463 | /* Return number of bytes at start of arglist that are not really args. */ | |
464 | ||
465 | #define FRAME_ARGS_SKIP 8 /* Not sure on this. FIXMEmgo */ | |
466 | ||
467 | /* Put here the code to store, into a struct frame_saved_regs, | |
468 | the addresses of the saved registers of frame described by FRAME_INFO. | |
469 | This includes special registers such as pc and fp saved in special | |
470 | ways in the stack frame. sp is even more special: | |
471 | the address we return for it IS the sp for the next frame. */ | |
2b5a8d9c PB |
472 | /* In the following implementation for RS6000, we did *not* save sp. I am |
473 | not sure if it will be needed. The following macro takes care of gpr's | |
474 | and fpr's only. */ | |
475 | ||
476 | #define FRAME_FIND_SAVED_REGS(FRAME_INFO, FRAME_SAVED_REGS) \ | |
477 | { \ | |
d6434f39 JG |
478 | int ii; \ |
479 | CORE_ADDR frame_addr, func_start; \ | |
480 | struct aix_framedata fdata; \ | |
481 | \ | |
482 | /* find the start of the function and collect info about its frame. */\ | |
483 | \ | |
484 | func_start = get_pc_function_start ((FRAME_INFO)->pc) + FUNCTION_START_OFFSET; \ | |
485 | function_frame_info (func_start, &fdata); \ | |
486 | bzero (&(FRAME_SAVED_REGS), sizeof (FRAME_SAVED_REGS)); \ | |
487 | \ | |
488 | /* if there were any saved registers, figure out parent's stack pointer. */ \ | |
489 | frame_addr = 0; \ | |
490 | /* the following is true only if the frame doesn't have a call to alloca(), \ | |
491 | FIXME. */ \ | |
492 | if (fdata.saved_fpr >= 0 || fdata.saved_gpr >= 0) { \ | |
493 | if ((FRAME_INFO)->prev && (FRAME_INFO)->prev->frame) \ | |
494 | frame_addr = (FRAME_INFO)->prev->frame; \ | |
495 | else \ | |
496 | frame_addr = read_memory_integer ((FRAME_INFO)->frame, 4); \ | |
497 | } \ | |
498 | \ | |
499 | /* if != -1, fdata.saved_fpr is the smallest number of saved_fpr. All fpr's \ | |
500 | from saved_fpr to fp31 are saved right underneath caller stack pointer, \ | |
501 | starting from fp31 first. */ \ | |
502 | \ | |
503 | if (fdata.saved_fpr >= 0) { \ | |
504 | for (ii=31; ii >= fdata.saved_fpr; --ii) \ | |
505 | (FRAME_SAVED_REGS).regs [FP0_REGNUM + ii] = frame_addr - ((32 - ii) * 8); \ | |
506 | frame_addr -= (32 - fdata.saved_fpr) * 8; \ | |
507 | } \ | |
508 | \ | |
509 | /* if != -1, fdata.saved_gpr is the smallest number of saved_gpr. All gpr's \ | |
510 | from saved_gpr to gpr31 are saved right under saved fprs, starting \ | |
511 | from r31 first. */ \ | |
512 | \ | |
513 | if (fdata.saved_gpr >= 0) \ | |
514 | for (ii=31; ii >= fdata.saved_gpr; --ii) \ | |
515 | (FRAME_SAVED_REGS).regs [ii] = frame_addr - ((32 - ii) * 4); \ | |
2b5a8d9c | 516 | } |
41abdfbd | 517 | |
41abdfbd JG |
518 | \f |
519 | /* Things needed for making the inferior call functions. */ | |
520 | ||
521 | /* Push an empty stack frame, to record the current PC, etc. */ | |
522 | /* Change these names into rs6k_{push, pop}_frame(). FIXMEmgo. */ | |
523 | ||
524 | #define PUSH_DUMMY_FRAME push_dummy_frame () | |
525 | ||
526 | /* Discard from the stack the innermost frame, | |
527 | restoring all saved registers. */ | |
528 | ||
529 | #define POP_FRAME pop_frame () | |
530 | ||
531 | /* This sequence of words is the instructions: | |
532 | ||
533 | mflr r0 // 0x7c0802a6 | |
534 | // save fpr's | |
535 | stfd r?, num(r1) // 0xd8010000 there should be 32 of this?? | |
536 | // save gpr's | |
537 | stm r0, num(r1) // 0xbc010000 | |
538 | stu r1, num(r1) // 0x94210000 | |
539 | ||
540 | // the function we want to branch might be in a different load | |
541 | // segment. reset the toc register. Note that the actual toc address | |
542 | // will be fix by fix_call_dummy () along with function address. | |
543 | ||
544 | st r2, 0x14(r1) // 0x90410014 save toc register | |
545 | liu r2, 0x1234 // 0x3c401234 reset a new toc value 0x12345678 | |
546 | oril r2, r2,0x5678 // 0x60425678 | |
547 | ||
548 | // load absolute address 0x12345678 to r0 | |
549 | liu r0, 0x1234 // 0x3c001234 | |
550 | oril r0, r0,0x5678 // 0x60005678 | |
551 | mtctr r0 // 0x7c0903a6 ctr <- r0 | |
552 | bctrl // 0x4e800421 jump subroutine 0x12345678 (%ctr) | |
553 | cror 0xf, 0xf, 0xf // 0x4def7b82 | |
554 | brpt // 0x7d821008, breakpoint | |
555 | cror 0xf, 0xf, 0xf // 0x4def7b82 (for 8 byte alignment) | |
556 | ||
557 | ||
558 | We actually start executing by saving the toc register first, since the pushing | |
559 | of the registers is done by PUSH_DUMMY_FRAME. If this were real code, | |
560 | the arguments for the function called by the `bctrl' would be pushed | |
561 | between the `stu' and the `bctrl', and we could allow it to execute through. | |
562 | But the arguments have to be pushed by GDB after the PUSH_DUMMY_FRAME is done, | |
563 | and we cannot allow to push the registers again. | |
564 | */ | |
565 | ||
566 | #define CALL_DUMMY {0x7c0802a6, 0xd8010000, 0xbc010000, 0x94210000, \ | |
567 | 0x90410014, 0x3c401234, 0x60425678, \ | |
568 | 0x3c001234, 0x60005678, 0x7c0903a6, 0x4e800421, \ | |
569 | 0x4def7b82, 0x7d821008, 0x4def7b82 } | |
570 | ||
571 | ||
572 | /* keep this as multiple of 8 (%sp requires 8 byte alignment) */ | |
573 | #define CALL_DUMMY_LENGTH 56 | |
574 | ||
575 | #define CALL_DUMMY_START_OFFSET 16 | |
576 | ||
577 | /* Insert the specified number of args and function address | |
578 | into a call sequence of the above form stored at DUMMYNAME. */ | |
579 | ||
580 | #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, using_gcc) \ | |
581 | fix_call_dummy(dummyname, pc, fun, nargs, type) | |
818de002 PB |
582 | |
583 | /* Flag for machine-specific stuff in shared files. FIXME */ | |
1eeba686 | 584 | #define IBM6000_TARGET |
9b280a7f JG |
585 | |
586 | /* RS6000/AIX does not support PT_STEP. Has to be simulated. */ | |
587 | ||
588 | #define NO_SINGLE_STEP |