Commit | Line | Data |
---|---|---|
41abdfbd | 1 | /* Target-dependent code for GDB, the GNU debugger. |
211b564e | 2 | Copyright 1986, 1987, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997 |
07aa9fdc | 3 | Free Software Foundation, Inc. |
41abdfbd JG |
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 | |
6c9638b4 | 19 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
41abdfbd | 20 | |
41abdfbd | 21 | #include "defs.h" |
41abdfbd JG |
22 | #include "frame.h" |
23 | #include "inferior.h" | |
24 | #include "symtab.h" | |
25 | #include "target.h" | |
030fb5cb | 26 | #include "gdbcore.h" |
65eaea27 JL |
27 | #include "symfile.h" |
28 | #include "objfiles.h" | |
2aefe6e4 JK |
29 | #include "xcoffsolib.h" |
30 | ||
41abdfbd | 31 | extern int errno; |
41abdfbd | 32 | |
41abdfbd JG |
33 | /* Breakpoint shadows for the single step instructions will be kept here. */ |
34 | ||
35 | static struct sstep_breaks { | |
030fb5cb JK |
36 | /* Address, or 0 if this is not in use. */ |
37 | CORE_ADDR address; | |
38 | /* Shadow contents. */ | |
39 | char data[4]; | |
41abdfbd JG |
40 | } stepBreaks[2]; |
41 | ||
05d52ace PS |
42 | /* Hook for determining the TOC address when calling functions in the |
43 | inferior under AIX. The initialization code in rs6000-nat.c sets | |
44 | this hook to point to find_toc_address. */ | |
45 | ||
46 | CORE_ADDR (*find_toc_address_hook) PARAMS ((CORE_ADDR)) = NULL; | |
ecf4059f | 47 | |
05d52ace | 48 | /* Static function prototypes */ |
ecf4059f | 49 | |
cd8a3d84 SS |
50 | static CORE_ADDR branch_dest PARAMS ((int opcode, int instr, CORE_ADDR pc, |
51 | CORE_ADDR safety)); | |
ecf4059f | 52 | |
86a51f41 AC |
53 | static void frame_get_saved_regs PARAMS ((struct frame_info *fi, |
54 | struct rs6000_framedata *fdatap)); | |
cd8a3d84 | 55 | |
368f1e77 FF |
56 | static void pop_dummy_frame PARAMS ((void)); |
57 | ||
86a51f41 AC |
58 | static CORE_ADDR frame_initial_stack_address PARAMS ((struct frame_info *)); |
59 | ||
60 | /* Fill in fi->saved_regs */ | |
61 | ||
62 | struct frame_extra_info | |
63 | { | |
64 | /* Functions calling alloca() change the value of the stack | |
65 | pointer. We need to use initial stack pointer (which is saved in | |
66 | r31 by gcc) in such cases. If a compiler emits traceback table, | |
67 | then we should use the alloca register specified in traceback | |
68 | table. FIXME. */ | |
69 | CORE_ADDR initial_sp; /* initial stack pointer. */ \ | |
70 | }; | |
71 | ||
72 | void | |
73 | rs6000_init_extra_frame_info (fromleaf, fi) | |
74 | int fromleaf; | |
75 | struct frame_info *fi; | |
76 | { | |
77 | fi->extra_info = (struct frame_extra_info*) | |
78 | frame_obstack_alloc (sizeof (struct frame_extra_info)); | |
79 | fi->extra_info->initial_sp = 0; | |
80 | if (fi->next != (CORE_ADDR) 0 | |
81 | && fi->pc < TEXT_SEGMENT_BASE) | |
82 | /* We're in get_prev_frame_info */ | |
83 | /* and this is a special signal frame. */ | |
84 | /* (fi->pc will be some low address in the kernel, */ | |
85 | /* to which the signal handler returns). */ | |
86 | fi->signal_handler_caller = 1; | |
87 | } | |
88 | ||
89 | ||
90 | void | |
91 | rs6000_frame_init_saved_regs (fi) | |
92 | struct frame_info *fi; | |
93 | { | |
94 | frame_get_saved_regs (fi, NULL); | |
95 | } | |
96 | ||
97 | CORE_ADDR | |
98 | rs6000_frame_args_address (fi) | |
99 | struct frame_info *fi; | |
100 | { | |
101 | if (fi->extra_info->initial_sp != 0) | |
102 | return fi->extra_info->initial_sp; | |
103 | else | |
104 | return frame_initial_stack_address (fi); | |
105 | } | |
106 | ||
107 | ||
cd8a3d84 | 108 | /* Calculate the destination of a branch/jump. Return -1 if not a branch. */ |
41abdfbd | 109 | |
ecf4059f | 110 | static CORE_ADDR |
41abdfbd | 111 | branch_dest (opcode, instr, pc, safety) |
ecf4059f JG |
112 | int opcode; |
113 | int instr; | |
114 | CORE_ADDR pc; | |
115 | CORE_ADDR safety; | |
41abdfbd | 116 | { |
ecf4059f | 117 | CORE_ADDR dest; |
41abdfbd JG |
118 | int immediate; |
119 | int absolute; | |
120 | int ext_op; | |
121 | ||
122 | absolute = (int) ((instr >> 1) & 1); | |
123 | ||
124 | switch (opcode) { | |
125 | case 18 : | |
ecf4059f | 126 | immediate = ((instr & ~3) << 6) >> 6; /* br unconditional */ |
dc59e982 MM |
127 | if (absolute) |
128 | dest = immediate; | |
129 | else | |
130 | dest = pc + immediate; | |
131 | break; | |
41abdfbd JG |
132 | |
133 | case 16 : | |
dc59e982 | 134 | immediate = ((instr & ~3) << 16) >> 16; /* br conditional */ |
41abdfbd JG |
135 | if (absolute) |
136 | dest = immediate; | |
137 | else | |
138 | dest = pc + immediate; | |
139 | break; | |
140 | ||
141 | case 19 : | |
142 | ext_op = (instr>>1) & 0x3ff; | |
143 | ||
144 | if (ext_op == 16) /* br conditional register */ | |
0c6c5eeb PS |
145 | { |
146 | dest = read_register (LR_REGNUM) & ~3; | |
147 | ||
148 | /* If we are about to return from a signal handler, dest is | |
149 | something like 0x3c90. The current frame is a signal handler | |
150 | caller frame, upon completion of the sigreturn system call | |
151 | execution will return to the saved PC in the frame. */ | |
152 | if (dest < TEXT_SEGMENT_BASE) | |
153 | { | |
154 | struct frame_info *fi; | |
155 | ||
156 | fi = get_current_frame (); | |
157 | if (fi != NULL) | |
158 | dest = read_memory_integer (fi->frame + SIG_FRAME_PC_OFFSET, | |
159 | 4); | |
160 | } | |
161 | } | |
41abdfbd JG |
162 | |
163 | else if (ext_op == 528) /* br cond to count reg */ | |
9aa31e91 JK |
164 | { |
165 | dest = read_register (CTR_REGNUM) & ~3; | |
166 | ||
167 | /* If we are about to execute a system call, dest is something | |
168 | like 0x22fc or 0x3b00. Upon completion the system call | |
169 | will return to the address in the link register. */ | |
170 | if (dest < TEXT_SEGMENT_BASE) | |
171 | dest = read_register (LR_REGNUM) & ~3; | |
172 | } | |
41abdfbd JG |
173 | else return -1; |
174 | break; | |
175 | ||
176 | default: return -1; | |
177 | } | |
818de002 | 178 | return (dest < TEXT_SEGMENT_BASE) ? safety : dest; |
41abdfbd JG |
179 | } |
180 | ||
181 | ||
afcad54a AC |
182 | /* Sequence of bytes for breakpoint instruction. */ |
183 | ||
184 | #define BIG_BREAKPOINT { 0x7d, 0x82, 0x10, 0x08 } | |
185 | #define LITTLE_BREAKPOINT { 0x08, 0x10, 0x82, 0x7d } | |
186 | ||
187 | unsigned char * | |
188 | rs6000_breakpoint_from_pc (bp_addr, bp_size) | |
189 | CORE_ADDR *bp_addr; | |
190 | int *bp_size; | |
191 | { | |
07137a11 AC |
192 | static unsigned char big_breakpoint[] = BIG_BREAKPOINT; |
193 | static unsigned char little_breakpoint[] = LITTLE_BREAKPOINT; | |
afcad54a AC |
194 | *bp_size = 4; |
195 | if (TARGET_BYTE_ORDER == BIG_ENDIAN) | |
196 | return big_breakpoint; | |
197 | else | |
198 | return little_breakpoint; | |
199 | } | |
200 | ||
41abdfbd JG |
201 | |
202 | /* AIX does not support PT_STEP. Simulate it. */ | |
203 | ||
997cc2c0 | 204 | void |
02331869 | 205 | rs6000_software_single_step (signal, insert_breakpoints_p) |
b607efe7 | 206 | enum target_signal signal; |
02331869 | 207 | int insert_breakpoints_p; |
41abdfbd JG |
208 | { |
209 | #define INSNLEN(OPCODE) 4 | |
210 | ||
5c172b4b MM |
211 | static char le_breakp[] = LITTLE_BREAKPOINT; |
212 | static char be_breakp[] = BIG_BREAKPOINT; | |
213 | char *breakp = TARGET_BYTE_ORDER == BIG_ENDIAN ? be_breakp : le_breakp; | |
030fb5cb JK |
214 | int ii, insn; |
215 | CORE_ADDR loc; | |
216 | CORE_ADDR breaks[2]; | |
217 | int opcode; | |
41abdfbd | 218 | |
02331869 AC |
219 | if (insert_breakpoints_p) { |
220 | ||
41abdfbd JG |
221 | loc = read_pc (); |
222 | ||
b112f2ae | 223 | insn = read_memory_integer (loc, 4); |
41abdfbd JG |
224 | |
225 | breaks[0] = loc + INSNLEN(insn); | |
226 | opcode = insn >> 26; | |
227 | breaks[1] = branch_dest (opcode, insn, loc, breaks[0]); | |
228 | ||
818de002 PB |
229 | /* Don't put two breakpoints on the same address. */ |
230 | if (breaks[1] == breaks[0]) | |
231 | breaks[1] = -1; | |
232 | ||
030fb5cb | 233 | stepBreaks[1].address = 0; |
41abdfbd JG |
234 | |
235 | for (ii=0; ii < 2; ++ii) { | |
236 | ||
237 | /* ignore invalid breakpoint. */ | |
238 | if ( breaks[ii] == -1) | |
239 | continue; | |
240 | ||
030fb5cb | 241 | read_memory (breaks[ii], stepBreaks[ii].data, 4); |
41abdfbd | 242 | |
030fb5cb | 243 | write_memory (breaks[ii], breakp, 4); |
41abdfbd JG |
244 | stepBreaks[ii].address = breaks[ii]; |
245 | } | |
246 | ||
997cc2c0 | 247 | } else { |
41abdfbd JG |
248 | |
249 | /* remove step breakpoints. */ | |
250 | for (ii=0; ii < 2; ++ii) | |
030fb5cb | 251 | if (stepBreaks[ii].address != 0) |
41abdfbd | 252 | write_memory |
030fb5cb | 253 | (stepBreaks[ii].address, stepBreaks[ii].data, 4); |
41abdfbd | 254 | |
41abdfbd | 255 | } |
997cc2c0 | 256 | errno = 0; /* FIXME, don't ignore errors! */ |
030fb5cb | 257 | /* What errors? {read,write}_memory call error(). */ |
41abdfbd | 258 | } |
41abdfbd JG |
259 | |
260 | ||
068c9fd6 MM |
261 | /* return pc value after skipping a function prologue and also return |
262 | information about a function frame. | |
41abdfbd | 263 | |
63d7a4f1 | 264 | in struct rs6000_framedata fdata: |
068c9fd6 MM |
265 | - frameless is TRUE, if function does not have a frame. |
266 | - nosavedpc is TRUE, if function does not save %pc value in its frame. | |
63d7a4f1 JB |
267 | - offset is the initial size of this stack frame --- the amount by |
268 | which we decrement the sp to allocate the frame. | |
068c9fd6 MM |
269 | - saved_gpr is the number of the first saved gpr. |
270 | - saved_fpr is the number of the first saved fpr. | |
271 | - alloca_reg is the number of the register used for alloca() handling. | |
272 | Otherwise -1. | |
63d7a4f1 JB |
273 | - gpr_offset is the offset of the first saved gpr from the previous frame. |
274 | - fpr_offset is the offset of the first saved fpr from the previous frame. | |
068c9fd6 MM |
275 | - lr_offset is the offset of the saved lr |
276 | - cr_offset is the offset of the saved cr | |
63d7a4f1 | 277 | */ |
068c9fd6 MM |
278 | |
279 | #define SIGNED_SHORT(x) \ | |
280 | ((sizeof (short) == 2) \ | |
281 | ? ((int)(short)(x)) \ | |
282 | : ((int)((((x) & 0xffff) ^ 0x8000) - 0x8000))) | |
283 | ||
284 | #define GET_SRC_REG(x) (((x) >> 21) & 0x1f) | |
285 | ||
286 | CORE_ADDR | |
287 | skip_prologue (pc, fdata) | |
288 | CORE_ADDR pc; | |
289 | struct rs6000_framedata *fdata; | |
41abdfbd | 290 | { |
068c9fd6 | 291 | CORE_ADDR orig_pc = pc; |
34df79fc | 292 | char buf[4]; |
34df79fc | 293 | unsigned long op; |
4b4c6c96 | 294 | long offset = 0; |
068c9fd6 MM |
295 | int lr_reg = 0; |
296 | int cr_reg = 0; | |
297 | int reg; | |
4b4c6c96 | 298 | int framep = 0; |
65eaea27 | 299 | int minimal_toc_loaded = 0; |
068c9fd6 MM |
300 | static struct rs6000_framedata zero_frame; |
301 | ||
302 | *fdata = zero_frame; | |
303 | fdata->saved_gpr = -1; | |
304 | fdata->saved_fpr = -1; | |
305 | fdata->alloca_reg = -1; | |
306 | fdata->frameless = 1; | |
307 | fdata->nosavedpc = 1; | |
41abdfbd | 308 | |
34df79fc | 309 | if (target_read_memory (pc, buf, 4)) |
41abdfbd | 310 | return pc; /* Can't access it -- assume no prologue. */ |
41abdfbd JG |
311 | |
312 | /* Assume that subsequent fetches can fail with low probability. */ | |
068c9fd6 MM |
313 | pc -= 4; |
314 | for (;;) | |
315 | { | |
316 | pc += 4; | |
317 | op = read_memory_integer (pc, 4); | |
41abdfbd | 318 | |
068c9fd6 MM |
319 | if ((op & 0xfc1fffff) == 0x7c0802a6) { /* mflr Rx */ |
320 | lr_reg = (op & 0x03e00000) | 0x90010000; | |
321 | continue; | |
322 | ||
323 | } else if ((op & 0xfc1fffff) == 0x7c000026) { /* mfcr Rx */ | |
324 | cr_reg = (op & 0x03e00000) | 0x90010000; | |
325 | continue; | |
326 | ||
327 | } else if ((op & 0xfc1f0000) == 0xd8010000) { /* stfd Rx,NUM(r1) */ | |
328 | reg = GET_SRC_REG (op); | |
329 | if (fdata->saved_fpr == -1 || fdata->saved_fpr > reg) { | |
330 | fdata->saved_fpr = reg; | |
4b4c6c96 | 331 | fdata->fpr_offset = SIGNED_SHORT (op) + offset; |
068c9fd6 MM |
332 | } |
333 | continue; | |
334 | ||
335 | } else if (((op & 0xfc1f0000) == 0xbc010000) || /* stm Rx, NUM(r1) */ | |
75621b2b MS |
336 | ((op & 0xfc1f0000) == 0x90010000 && /* st rx,NUM(r1), |
337 | rx >= r13 */ | |
068c9fd6 MM |
338 | (op & 0x03e00000) >= 0x01a00000)) { |
339 | ||
340 | reg = GET_SRC_REG (op); | |
341 | if (fdata->saved_gpr == -1 || fdata->saved_gpr > reg) { | |
342 | fdata->saved_gpr = reg; | |
4b4c6c96 | 343 | fdata->gpr_offset = SIGNED_SHORT (op) + offset; |
068c9fd6 MM |
344 | } |
345 | continue; | |
346 | ||
75621b2b MS |
347 | } else if ((op & 0xffff0000) == 0x3c000000) { /* addis 0,0,NUM, used |
348 | for >= 32k frames */ | |
068c9fd6 | 349 | fdata->offset = (op & 0x0000ffff) << 16; |
65eaea27 | 350 | fdata->frameless = 0; |
068c9fd6 MM |
351 | continue; |
352 | ||
75621b2b MS |
353 | } else if ((op & 0xffff0000) == 0x60000000) { /* ori 0,0,NUM, 2nd ha |
354 | lf of >= 32k frames */ | |
068c9fd6 | 355 | fdata->offset |= (op & 0x0000ffff); |
65eaea27 | 356 | fdata->frameless = 0; |
068c9fd6 MM |
357 | continue; |
358 | ||
75621b2b MS |
359 | } else if ((op & 0xffff0000) == lr_reg) { /* st Rx,NUM(r1) |
360 | where Rx == lr */ | |
4b4c6c96 | 361 | fdata->lr_offset = SIGNED_SHORT (op) + offset; |
068c9fd6 MM |
362 | fdata->nosavedpc = 0; |
363 | lr_reg = 0; | |
364 | continue; | |
365 | ||
75621b2b MS |
366 | } else if ((op & 0xffff0000) == cr_reg) { /* st Rx,NUM(r1) |
367 | where Rx == cr */ | |
4b4c6c96 | 368 | fdata->cr_offset = SIGNED_SHORT (op) + offset; |
068c9fd6 MM |
369 | cr_reg = 0; |
370 | continue; | |
371 | ||
75621b2b MS |
372 | } else if (op == 0x48000005) { /* bl .+4 used in |
373 | -mrelocatable */ | |
4b4c6c96 MM |
374 | continue; |
375 | ||
65eaea27 JL |
376 | } else if (op == 0x48000004) { /* b .+4 (xlc) */ |
377 | break; | |
378 | ||
75621b2b MS |
379 | } else if (((op & 0xffff0000) == 0x801e0000 || /* lwz 0,NUM(r30), used |
380 | in V.4 -mrelocatable */ | |
381 | op == 0x7fc0f214) && /* add r30,r0,r30, used | |
382 | in V.4 -mrelocatable */ | |
4b4c6c96 MM |
383 | lr_reg == 0x901e0000) { |
384 | continue; | |
385 | ||
75621b2b MS |
386 | } else if ((op & 0xffff0000) == 0x3fc00000 || /* addis 30,0,foo@ha, used |
387 | in V.4 -mminimal-toc */ | |
4b4c6c96 MM |
388 | (op & 0xffff0000) == 0x3bde0000) { /* addi 30,30,foo@l */ |
389 | continue; | |
390 | ||
75621b2b MS |
391 | } else if ((op & 0xfc000000) == 0x48000000) { /* bl foo, |
392 | to save fprs??? */ | |
965dde97 | 393 | |
65eaea27 | 394 | fdata->frameless = 0; |
965dde97 PS |
395 | /* Don't skip over the subroutine call if it is not within the first |
396 | three instructions of the prologue. */ | |
397 | if ((pc - orig_pc) > 8) | |
398 | break; | |
399 | ||
068c9fd6 MM |
400 | op = read_memory_integer (pc+4, 4); |
401 | ||
402 | /* At this point, make sure this is not a trampoline function | |
403 | (a function that simply calls another functions, and nothing else). | |
404 | If the next is not a nop, this branch was part of the function | |
405 | prologue. */ | |
406 | ||
407 | if (op == 0x4def7b82 || op == 0) /* crorc 15, 15, 15 */ | |
75621b2b MS |
408 | break; /* don't skip over |
409 | this branch */ | |
068c9fd6 MM |
410 | continue; |
411 | ||
4b4c6c96 | 412 | /* update stack pointer */ |
068c9fd6 | 413 | } else if ((op & 0xffff0000) == 0x94210000) { /* stu r1,NUM(r1) */ |
65eaea27 | 414 | fdata->frameless = 0; |
4b4c6c96 MM |
415 | fdata->offset = SIGNED_SHORT (op); |
416 | offset = fdata->offset; | |
417 | continue; | |
1eeba686 | 418 | |
068c9fd6 | 419 | } else if (op == 0x7c21016e) { /* stwux 1,1,0 */ |
65eaea27 | 420 | fdata->frameless = 0; |
4b4c6c96 MM |
421 | offset = fdata->offset; |
422 | continue; | |
41abdfbd | 423 | |
4b4c6c96 | 424 | /* Load up minimal toc pointer */ |
65eaea27 JL |
425 | } else if ((op >> 22) == 0x20f |
426 | && ! minimal_toc_loaded) { /* l r31,... or l r30,... */ | |
427 | minimal_toc_loaded = 1; | |
4b4c6c96 | 428 | continue; |
cdb1cc92 | 429 | |
4b4c6c96 MM |
430 | /* store parameters in stack */ |
431 | } else if ((op & 0xfc1f0000) == 0x90010000 || /* st rx,NUM(r1) */ | |
432 | (op & 0xfc1f0000) == 0xd8010000 || /* stfd Rx,NUM(r1) */ | |
433 | (op & 0xfc1f0000) == 0xfc010000) { /* frsp, fp?,NUM(r1) */ | |
434 | continue; | |
e137e850 | 435 | |
4b4c6c96 MM |
436 | /* store parameters in stack via frame pointer */ |
437 | } else if (framep && | |
58b4fad2 | 438 | ((op & 0xfc1f0000) == 0x901f0000 || /* st rx,NUM(r1) */ |
4b4c6c96 | 439 | (op & 0xfc1f0000) == 0xd81f0000 || /* stfd Rx,NUM(r1) */ |
58b4fad2 | 440 | (op & 0xfc1f0000) == 0xfc1f0000)) { /* frsp, fp?,NUM(r1) */ |
4b4c6c96 | 441 | continue; |
e137e850 | 442 | |
4b4c6c96 MM |
443 | /* Set up frame pointer */ |
444 | } else if (op == 0x603f0000 /* oril r31, r1, 0x0 */ | |
445 | || op == 0x7c3f0b78) { /* mr r31, r1 */ | |
65eaea27 | 446 | fdata->frameless = 0; |
4b4c6c96 | 447 | framep = 1; |
965dde97 | 448 | fdata->alloca_reg = 31; |
4b4c6c96 | 449 | continue; |
41abdfbd | 450 | |
65eaea27 JL |
451 | /* Another way to set up the frame pointer. */ |
452 | } else if ((op & 0xfc1fffff) == 0x38010000) { /* addi rX, r1, 0x0 */ | |
453 | fdata->frameless = 0; | |
454 | framep = 1; | |
455 | fdata->alloca_reg = (op & ~0x38010000) >> 21; | |
456 | continue; | |
457 | ||
4b4c6c96 MM |
458 | } else { |
459 | break; | |
460 | } | |
41abdfbd | 461 | } |
068c9fd6 | 462 | |
507e4004 PB |
463 | #if 0 |
464 | /* I have problems with skipping over __main() that I need to address | |
465 | * sometime. Previously, I used to use misc_function_vector which | |
466 | * didn't work as well as I wanted to be. -MGO */ | |
467 | ||
468 | /* If the first thing after skipping a prolog is a branch to a function, | |
469 | this might be a call to an initializer in main(), introduced by gcc2. | |
470 | We'd like to skip over it as well. Fortunately, xlc does some extra | |
471 | work before calling a function right after a prologue, thus we can | |
472 | single out such gcc2 behaviour. */ | |
473 | ||
474 | ||
475 | if ((op & 0xfc000001) == 0x48000001) { /* bl foo, an initializer function? */ | |
476 | op = read_memory_integer (pc+4, 4); | |
477 | ||
478 | if (op == 0x4def7b82) { /* cror 0xf, 0xf, 0xf (nop) */ | |
479 | ||
480 | /* check and see if we are in main. If so, skip over this initializer | |
481 | function as well. */ | |
482 | ||
483 | tmp = find_pc_misc_function (pc); | |
2e4964ad | 484 | if (tmp >= 0 && STREQ (misc_function_vector [tmp].name, "main")) |
507e4004 PB |
485 | return pc + 8; |
486 | } | |
487 | } | |
488 | #endif /* 0 */ | |
489 | ||
4b4c6c96 | 490 | fdata->offset = - fdata->offset; |
41abdfbd JG |
491 | return pc; |
492 | } | |
493 | ||
818de002 | 494 | |
41abdfbd JG |
495 | /************************************************************************* |
496 | Support for creating pushind a dummy frame into the stack, and popping | |
497 | frames, etc. | |
498 | *************************************************************************/ | |
499 | ||
818de002 PB |
500 | /* The total size of dummy frame is 436, which is; |
501 | ||
502 | 32 gpr's - 128 bytes | |
503 | 32 fpr's - 256 " | |
504 | 7 the rest - 28 " | |
505 | and 24 extra bytes for the callee's link area. The last 24 bytes | |
506 | for the link area might not be necessary, since it will be taken | |
507 | care of by push_arguments(). */ | |
508 | ||
509 | #define DUMMY_FRAME_SIZE 436 | |
510 | ||
41abdfbd JG |
511 | #define DUMMY_FRAME_ADDR_SIZE 10 |
512 | ||
513 | /* Make sure you initialize these in somewhere, in case gdb gives up what it | |
818de002 | 514 | was debugging and starts debugging something else. FIXMEibm */ |
41abdfbd JG |
515 | |
516 | static int dummy_frame_count = 0; | |
517 | static int dummy_frame_size = 0; | |
518 | static CORE_ADDR *dummy_frame_addr = 0; | |
519 | ||
520 | extern int stop_stack_dummy; | |
521 | ||
522 | /* push a dummy frame into stack, save all register. Currently we are saving | |
523 | only gpr's and fpr's, which is not good enough! FIXMEmgo */ | |
524 | ||
ecf4059f | 525 | void |
41abdfbd JG |
526 | push_dummy_frame () |
527 | { | |
359a097f JK |
528 | /* stack pointer. */ |
529 | CORE_ADDR sp; | |
b112f2ae JK |
530 | /* Same thing, target byte order. */ |
531 | char sp_targ[4]; | |
359a097f JK |
532 | |
533 | /* link register. */ | |
534 | CORE_ADDR pc; | |
535 | /* Same thing, target byte order. */ | |
536 | char pc_targ[4]; | |
537 | ||
3a4f9786 MT |
538 | /* Needed to figure out where to save the dummy link area. |
539 | FIXME: There should be an easier way to do this, no? tiemann 9/9/95. */ | |
540 | struct rs6000_framedata fdata; | |
541 | ||
41abdfbd JG |
542 | int ii; |
543 | ||
5f1c39ef | 544 | target_fetch_registers (-1); |
6c6afbb9 | 545 | |
41abdfbd JG |
546 | if (dummy_frame_count >= dummy_frame_size) { |
547 | dummy_frame_size += DUMMY_FRAME_ADDR_SIZE; | |
548 | if (dummy_frame_addr) | |
549 | dummy_frame_addr = (CORE_ADDR*) xrealloc | |
550 | (dummy_frame_addr, sizeof(CORE_ADDR) * (dummy_frame_size)); | |
551 | else | |
552 | dummy_frame_addr = (CORE_ADDR*) | |
553 | xmalloc (sizeof(CORE_ADDR) * (dummy_frame_size)); | |
554 | } | |
555 | ||
556 | sp = read_register(SP_REGNUM); | |
359a097f | 557 | pc = read_register(PC_REGNUM); |
5816555b | 558 | store_address (pc_targ, 4, pc); |
41abdfbd | 559 | |
86a51f41 | 560 | skip_prologue (get_pc_function_start (pc), &fdata); |
3a4f9786 | 561 | |
41abdfbd JG |
562 | dummy_frame_addr [dummy_frame_count++] = sp; |
563 | ||
564 | /* Be careful! If the stack pointer is not decremented first, then kernel | |
6c6afbb9 | 565 | thinks he is free to use the space underneath it. And kernel actually |
41abdfbd JG |
566 | uses that area for IPC purposes when executing ptrace(2) calls. So |
567 | before writing register values into the new frame, decrement and update | |
568 | %sp first in order to secure your frame. */ | |
569 | ||
3a4f9786 MT |
570 | /* FIXME: We don't check if the stack really has this much space. |
571 | This is a problem on the ppc simulator (which only grants one page | |
572 | (4096 bytes) by default. */ | |
573 | ||
818de002 | 574 | write_register (SP_REGNUM, sp-DUMMY_FRAME_SIZE); |
41abdfbd | 575 | |
41abdfbd JG |
576 | /* gdb relies on the state of current_frame. We'd better update it, |
577 | otherwise things like do_registers_info() wouldn't work properly! */ | |
578 | ||
579 | flush_cached_frames (); | |
41abdfbd JG |
580 | |
581 | /* save program counter in link register's space. */ | |
4f8710e6 PS |
582 | write_memory (sp + (fdata.lr_offset ? fdata.lr_offset : DEFAULT_LR_SAVE), |
583 | pc_targ, 4); | |
41abdfbd | 584 | |
6c6afbb9 | 585 | /* save all floating point and general purpose registers here. */ |
41abdfbd JG |
586 | |
587 | /* fpr's, f0..f31 */ | |
588 | for (ii = 0; ii < 32; ++ii) | |
589 | write_memory (sp-8-(ii*8), ®isters[REGISTER_BYTE (31-ii+FP0_REGNUM)], 8); | |
590 | ||
591 | /* gpr's r0..r31 */ | |
592 | for (ii=1; ii <=32; ++ii) | |
593 | write_memory (sp-256-(ii*4), ®isters[REGISTER_BYTE (32-ii)], 4); | |
594 | ||
818de002 PB |
595 | /* so far, 32*2 + 32 words = 384 bytes have been written. |
596 | 7 extra registers in our register set: pc, ps, cnd, lr, cnt, xer, mq */ | |
597 | ||
598 | for (ii=1; ii <= (LAST_SP_REGNUM-FIRST_SP_REGNUM+1); ++ii) { | |
599 | write_memory (sp-384-(ii*4), | |
75621b2b | 600 | ®isters[REGISTER_BYTE (FPLAST_REGNUM + ii)], 4); |
818de002 PB |
601 | } |
602 | ||
603 | /* Save sp or so called back chain right here. */ | |
b112f2ae JK |
604 | store_address (sp_targ, 4, sp); |
605 | write_memory (sp-DUMMY_FRAME_SIZE, sp_targ, 4); | |
818de002 | 606 | sp -= DUMMY_FRAME_SIZE; |
41abdfbd JG |
607 | |
608 | /* And finally, this is the back chain. */ | |
359a097f | 609 | write_memory (sp+8, pc_targ, 4); |
41abdfbd JG |
610 | } |
611 | ||
612 | ||
613 | /* Pop a dummy frame. | |
614 | ||
615 | In rs6000 when we push a dummy frame, we save all of the registers. This | |
616 | is usually done before user calls a function explicitly. | |
617 | ||
818de002 PB |
618 | After a dummy frame is pushed, some instructions are copied into stack, |
619 | and stack pointer is decremented even more. Since we don't have a frame | |
620 | pointer to get back to the parent frame of the dummy, we start having | |
621 | trouble poping it. Therefore, we keep a dummy frame stack, keeping | |
622 | addresses of dummy frames as such. When poping happens and when we | |
623 | detect that was a dummy frame, we pop it back to its parent by using | |
624 | dummy frame stack (`dummy_frame_addr' array). | |
ecf4059f JG |
625 | |
626 | FIXME: This whole concept is broken. You should be able to detect | |
627 | a dummy stack frame *on the user's stack itself*. When you do, | |
628 | then you know the format of that stack frame -- including its | |
629 | saved SP register! There should *not* be a separate stack in the | |
d6434f39 | 630 | GDB process that keeps track of these dummy frames! -- gnu@cygnus.com Aug92 |
41abdfbd JG |
631 | */ |
632 | ||
368f1e77 | 633 | static void |
41abdfbd JG |
634 | pop_dummy_frame () |
635 | { | |
636 | CORE_ADDR sp, pc; | |
637 | int ii; | |
638 | sp = dummy_frame_addr [--dummy_frame_count]; | |
639 | ||
640 | /* restore all fpr's. */ | |
641 | for (ii = 1; ii <= 32; ++ii) | |
642 | read_memory (sp-(ii*8), ®isters[REGISTER_BYTE (32-ii+FP0_REGNUM)], 8); | |
643 | ||
644 | /* restore all gpr's */ | |
645 | for (ii=1; ii <= 32; ++ii) { | |
646 | read_memory (sp-256-(ii*4), ®isters[REGISTER_BYTE (32-ii)], 4); | |
647 | } | |
648 | ||
818de002 PB |
649 | /* restore the rest of the registers. */ |
650 | for (ii=1; ii <=(LAST_SP_REGNUM-FIRST_SP_REGNUM+1); ++ii) | |
651 | read_memory (sp-384-(ii*4), | |
652 | ®isters[REGISTER_BYTE (FPLAST_REGNUM + ii)], 4); | |
653 | ||
654 | read_memory (sp-(DUMMY_FRAME_SIZE-8), | |
3a4f9786 | 655 | ®isters [REGISTER_BYTE(PC_REGNUM)], 4); |
41abdfbd JG |
656 | |
657 | /* when a dummy frame was being pushed, we had to decrement %sp first, in | |
658 | order to secure astack space. Thus, saved %sp (or %r1) value, is not the | |
659 | one we should restore. Change it with the one we need. */ | |
660 | ||
75621b2b | 661 | memcpy (®isters [REGISTER_BYTE(FP_REGNUM)], (char *) &sp, sizeof (int)); |
41abdfbd JG |
662 | |
663 | /* Now we can restore all registers. */ | |
664 | ||
5f1c39ef | 665 | target_store_registers (-1); |
41abdfbd JG |
666 | pc = read_pc (); |
667 | flush_cached_frames (); | |
41abdfbd JG |
668 | } |
669 | ||
670 | ||
671 | /* pop the innermost frame, go back to the caller. */ | |
672 | ||
ecf4059f | 673 | void |
41abdfbd JG |
674 | pop_frame () |
675 | { | |
359a097f | 676 | CORE_ADDR pc, lr, sp, prev_sp; /* %pc, %lr, %sp */ |
63641491 | 677 | struct rs6000_framedata fdata; |
669caa9c | 678 | struct frame_info *frame = get_current_frame (); |
41abdfbd | 679 | int addr, ii; |
41abdfbd JG |
680 | |
681 | pc = read_pc (); | |
669caa9c | 682 | sp = FRAME_FP (frame); |
41abdfbd | 683 | |
0ec1e44d MA |
684 | if (stop_stack_dummy) |
685 | { | |
686 | #ifdef USE_GENERIC_DUMMY_FRAMES | |
687 | generic_pop_dummy_frame (); | |
688 | flush_cached_frames (); | |
689 | return; | |
690 | #else | |
691 | if (dummy_frame_count) | |
692 | pop_dummy_frame (); | |
693 | return; | |
694 | #endif | |
695 | } | |
41abdfbd | 696 | |
07aa9fdc PS |
697 | /* Make sure that all registers are valid. */ |
698 | read_register_bytes (0, NULL, REGISTER_BYTES); | |
699 | ||
41abdfbd JG |
700 | /* figure out previous %pc value. If the function is frameless, it is |
701 | still in the link register, otherwise walk the frames and retrieve the | |
702 | saved %pc value in the previous frame. */ | |
703 | ||
86a51f41 | 704 | addr = get_pc_function_start (frame->pc); |
068c9fd6 | 705 | (void) skip_prologue (addr, &fdata); |
41abdfbd | 706 | |
6c6afbb9 | 707 | if (fdata.frameless) |
07aa9fdc PS |
708 | prev_sp = sp; |
709 | else | |
710 | prev_sp = read_memory_integer (sp, 4); | |
068c9fd6 | 711 | if (fdata.lr_offset == 0) |
41abdfbd JG |
712 | lr = read_register (LR_REGNUM); |
713 | else | |
068c9fd6 | 714 | lr = read_memory_integer (prev_sp + fdata.lr_offset, 4); |
41abdfbd JG |
715 | |
716 | /* reset %pc value. */ | |
717 | write_register (PC_REGNUM, lr); | |
718 | ||
719 | /* reset register values if any was saved earlier. */ | |
41abdfbd | 720 | |
6c6afbb9 | 721 | if (fdata.saved_gpr != -1) |
63d7a4f1 JB |
722 | { |
723 | addr = prev_sp + fdata.gpr_offset; | |
724 | for (ii = fdata.saved_gpr; ii <= 31; ++ii) { | |
725 | read_memory (addr, ®isters [REGISTER_BYTE (ii)], 4); | |
726 | addr += 4; | |
727 | } | |
41abdfbd JG |
728 | } |
729 | ||
6c6afbb9 | 730 | if (fdata.saved_fpr != -1) |
63d7a4f1 JB |
731 | { |
732 | addr = prev_sp + fdata.fpr_offset; | |
733 | for (ii = fdata.saved_fpr; ii <= 31; ++ii) { | |
734 | read_memory (addr, ®isters [REGISTER_BYTE (ii+FP0_REGNUM)], 8); | |
735 | addr += 8; | |
736 | } | |
737 | } | |
41abdfbd JG |
738 | |
739 | write_register (SP_REGNUM, prev_sp); | |
5f1c39ef | 740 | target_store_registers (-1); |
41abdfbd | 741 | flush_cached_frames (); |
41abdfbd JG |
742 | } |
743 | ||
41abdfbd JG |
744 | /* fixup the call sequence of a dummy function, with the real function address. |
745 | its argumets will be passed by gdb. */ | |
746 | ||
ecf4059f | 747 | void |
2f163bc3 | 748 | rs6000_fix_call_dummy (dummyname, pc, fun, nargs, args, type, gcc_p) |
cd8a3d84 SS |
749 | char *dummyname; |
750 | CORE_ADDR pc; | |
751 | CORE_ADDR fun; | |
2f163bc3 SS |
752 | int nargs; |
753 | value_ptr *args; | |
754 | struct type *type; | |
755 | int gcc_p; | |
41abdfbd JG |
756 | { |
757 | #define TOC_ADDR_OFFSET 20 | |
758 | #define TARGET_ADDR_OFFSET 28 | |
759 | ||
760 | int ii; | |
ecf4059f | 761 | CORE_ADDR target_addr; |
41abdfbd | 762 | |
05d52ace PS |
763 | if (find_toc_address_hook != NULL) |
764 | { | |
765 | CORE_ADDR tocvalue; | |
41abdfbd | 766 | |
05d52ace PS |
767 | tocvalue = (*find_toc_address_hook) (fun); |
768 | ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET); | |
769 | ii = (ii & 0xffff0000) | (tocvalue >> 16); | |
770 | *(int*)((char*)dummyname + TOC_ADDR_OFFSET) = ii; | |
41abdfbd | 771 | |
05d52ace PS |
772 | ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4); |
773 | ii = (ii & 0xffff0000) | (tocvalue & 0x0000ffff); | |
774 | *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4) = ii; | |
775 | } | |
41abdfbd | 776 | |
05d52ace | 777 | target_addr = fun; |
41abdfbd JG |
778 | ii = *(int*)((char*)dummyname + TARGET_ADDR_OFFSET); |
779 | ii = (ii & 0xffff0000) | (target_addr >> 16); | |
780 | *(int*)((char*)dummyname + TARGET_ADDR_OFFSET) = ii; | |
781 | ||
782 | ii = *(int*)((char*)dummyname + TARGET_ADDR_OFFSET+4); | |
783 | ii = (ii & 0xffff0000) | (target_addr & 0x0000ffff); | |
784 | *(int*)((char*)dummyname + TARGET_ADDR_OFFSET+4) = ii; | |
785 | } | |
786 | ||
cd8a3d84 SS |
787 | /* Pass the arguments in either registers, or in the stack. In RS6000, |
788 | the first eight words of the argument list (that might be less than | |
789 | eight parameters if some parameters occupy more than one word) are | |
790 | passed in r3..r11 registers. float and double parameters are | |
791 | passed in fpr's, in addition to that. Rest of the parameters if any | |
792 | are passed in user stack. There might be cases in which half of the | |
793 | parameter is copied into registers, the other half is pushed into | |
41abdfbd JG |
794 | stack. |
795 | ||
796 | If the function is returning a structure, then the return address is passed | |
94b4f756 | 797 | in r3, then the first 7 words of the parameters can be passed in registers, |
41abdfbd JG |
798 | starting from r4. */ |
799 | ||
800 | CORE_ADDR | |
801 | push_arguments (nargs, args, sp, struct_return, struct_addr) | |
cd8a3d84 SS |
802 | int nargs; |
803 | value_ptr *args; | |
804 | CORE_ADDR sp; | |
805 | int struct_return; | |
806 | CORE_ADDR struct_addr; | |
41abdfbd | 807 | { |
368f1e77 FF |
808 | int ii; |
809 | int len = 0; | |
41abdfbd JG |
810 | int argno; /* current argument number */ |
811 | int argbytes; /* current argument byte */ | |
812 | char tmp_buffer [50]; | |
41abdfbd | 813 | int f_argno = 0; /* current floating point argno */ |
0ec1e44d | 814 | |
368f1e77 | 815 | value_ptr arg = 0; |
940d5967 | 816 | struct type *type; |
41abdfbd | 817 | |
368f1e77 | 818 | CORE_ADDR saved_sp; |
41abdfbd | 819 | |
0ec1e44d | 820 | #ifndef USE_GENERIC_DUMMY_FRAMES |
41abdfbd | 821 | if ( dummy_frame_count <= 0) |
199b2450 | 822 | printf_unfiltered ("FATAL ERROR -push_arguments()! frame not found!!\n"); |
0ec1e44d | 823 | #endif /* GENERIC_DUMMY_FRAMES */ |
41abdfbd JG |
824 | |
825 | /* The first eight words of ther arguments are passed in registers. Copy | |
826 | them appropriately. | |
827 | ||
828 | If the function is returning a `struct', then the first word (which | |
829 | will be passed in r3) is used for struct return address. In that | |
830 | case we should advance one word and start from r4 register to copy | |
831 | parameters. */ | |
832 | ||
833 | ii = struct_return ? 1 : 0; | |
834 | ||
0ec1e44d MA |
835 | /* |
836 | effectively indirect call... gcc does... | |
837 | ||
838 | return_val example( float, int); | |
839 | ||
840 | eabi: | |
841 | float in fp0, int in r3 | |
842 | offset of stack on overflow 8/16 | |
843 | for varargs, must go by type. | |
844 | power open: | |
845 | float in r3&r4, int in r5 | |
846 | offset of stack on overflow different | |
847 | both: | |
848 | return in r3 or f0. If no float, must study how gcc emulates floats; | |
849 | pay attention to arg promotion. | |
850 | User may have to cast\args to handle promotion correctly | |
851 | since gdb won't know if prototype supplied or not. | |
852 | */ | |
853 | ||
41abdfbd JG |
854 | for (argno=0, argbytes=0; argno < nargs && ii<8; ++ii) { |
855 | ||
5222ca60 | 856 | arg = args[argno]; |
59c84318 | 857 | type = check_typedef (VALUE_TYPE (arg)); |
940d5967 | 858 | len = TYPE_LENGTH (type); |
41abdfbd | 859 | |
940d5967 | 860 | if (TYPE_CODE (type) == TYPE_CODE_FLT) { |
41abdfbd JG |
861 | |
862 | /* floating point arguments are passed in fpr's, as well as gpr's. | |
863 | There are 13 fpr's reserved for passing parameters. At this point | |
864 | there is no way we would run out of them. */ | |
865 | ||
866 | if (len > 8) | |
199b2450 | 867 | printf_unfiltered ( |
41abdfbd JG |
868 | "Fatal Error: a floating point parameter #%d with a size > 8 is found!\n", argno); |
869 | ||
75621b2b MS |
870 | memcpy (®isters[REGISTER_BYTE(FP0_REGNUM + 1 + f_argno)], |
871 | VALUE_CONTENTS (arg), | |
872 | len); | |
41abdfbd JG |
873 | ++f_argno; |
874 | } | |
875 | ||
876 | if (len > 4) { | |
877 | ||
878 | /* Argument takes more than one register. */ | |
879 | while (argbytes < len) { | |
75621b2b | 880 | memset (®isters[REGISTER_BYTE(ii+3)], 0, sizeof(int)); |
ade40d31 | 881 | memcpy (®isters[REGISTER_BYTE(ii+3)], |
75621b2b MS |
882 | ((char*)VALUE_CONTENTS (arg))+argbytes, |
883 | (len - argbytes) > 4 ? 4 : len - argbytes); | |
41abdfbd JG |
884 | ++ii, argbytes += 4; |
885 | ||
886 | if (ii >= 8) | |
887 | goto ran_out_of_registers_for_arguments; | |
888 | } | |
889 | argbytes = 0; | |
890 | --ii; | |
891 | } | |
892 | else { /* Argument can fit in one register. No problem. */ | |
75621b2b | 893 | memset (®isters[REGISTER_BYTE(ii+3)], 0, sizeof(int)); |
ade40d31 | 894 | memcpy (®isters[REGISTER_BYTE(ii+3)], VALUE_CONTENTS (arg), len); |
41abdfbd JG |
895 | } |
896 | ++argno; | |
897 | } | |
898 | ||
899 | ran_out_of_registers_for_arguments: | |
900 | ||
0ec1e44d MA |
901 | #ifdef USE_GENERIC_DUMMY_FRAMES |
902 | saved_sp = read_sp (); | |
903 | #else | |
41abdfbd JG |
904 | /* location for 8 parameters are always reserved. */ |
905 | sp -= 4 * 8; | |
906 | ||
907 | /* another six words for back chain, TOC register, link register, etc. */ | |
908 | sp -= 24; | |
0ec1e44d | 909 | #endif /* GENERIC_DUMMY_FRAMES */ |
41abdfbd JG |
910 | /* if there are more arguments, allocate space for them in |
911 | the stack, then push them starting from the ninth one. */ | |
912 | ||
913 | if ((argno < nargs) || argbytes) { | |
914 | int space = 0, jj; | |
41abdfbd JG |
915 | |
916 | if (argbytes) { | |
917 | space += ((len - argbytes + 3) & -4); | |
918 | jj = argno + 1; | |
919 | } | |
920 | else | |
921 | jj = argno; | |
922 | ||
923 | for (; jj < nargs; ++jj) { | |
940d5967 | 924 | value_ptr val = args[jj]; |
41abdfbd JG |
925 | space += ((TYPE_LENGTH (VALUE_TYPE (val))) + 3) & -4; |
926 | } | |
927 | ||
928 | /* add location required for the rest of the parameters */ | |
929 | space = (space + 7) & -8; | |
930 | sp -= space; | |
931 | ||
932 | /* This is another instance we need to be concerned about securing our | |
933 | stack space. If we write anything underneath %sp (r1), we might conflict | |
934 | with the kernel who thinks he is free to use this area. So, update %sp | |
935 | first before doing anything else. */ | |
936 | ||
937 | write_register (SP_REGNUM, sp); | |
938 | ||
41abdfbd JG |
939 | /* if the last argument copied into the registers didn't fit there |
940 | completely, push the rest of it into stack. */ | |
941 | ||
942 | if (argbytes) { | |
75621b2b MS |
943 | write_memory (sp+24+(ii*4), |
944 | ((char*)VALUE_CONTENTS (arg))+argbytes, | |
945 | len - argbytes); | |
41abdfbd JG |
946 | ++argno; |
947 | ii += ((len - argbytes + 3) & -4) / 4; | |
948 | } | |
949 | ||
950 | /* push the rest of the arguments into stack. */ | |
951 | for (; argno < nargs; ++argno) { | |
952 | ||
5222ca60 | 953 | arg = args[argno]; |
940d5967 PB |
954 | type = check_typedef (VALUE_TYPE (arg)); |
955 | len = TYPE_LENGTH (type); | |
41abdfbd JG |
956 | |
957 | ||
958 | /* float types should be passed in fpr's, as well as in the stack. */ | |
940d5967 | 959 | if (TYPE_CODE (type) == TYPE_CODE_FLT && f_argno < 13) { |
41abdfbd JG |
960 | |
961 | if (len > 8) | |
199b2450 | 962 | printf_unfiltered ( |
41abdfbd JG |
963 | "Fatal Error: a floating point parameter #%d with a size > 8 is found!\n", argno); |
964 | ||
75621b2b MS |
965 | memcpy (®isters[REGISTER_BYTE(FP0_REGNUM + 1 + f_argno)], |
966 | VALUE_CONTENTS (arg), | |
967 | len); | |
41abdfbd JG |
968 | ++f_argno; |
969 | } | |
970 | ||
359a097f | 971 | write_memory (sp+24+(ii*4), (char *) VALUE_CONTENTS (arg), len); |
41abdfbd JG |
972 | ii += ((len + 3) & -4) / 4; |
973 | } | |
974 | } | |
6c6afbb9 | 975 | else |
41abdfbd JG |
976 | /* Secure stack areas first, before doing anything else. */ |
977 | write_register (SP_REGNUM, sp); | |
978 | ||
0ec1e44d MA |
979 | #ifndef USE_GENERIC_DUMMY_FRAMES |
980 | /* we want to copy 24 bytes of target's frame to dummy's frame, | |
981 | then set back chain to point to new frame. */ | |
982 | ||
41abdfbd JG |
983 | saved_sp = dummy_frame_addr [dummy_frame_count - 1]; |
984 | read_memory (saved_sp, tmp_buffer, 24); | |
985 | write_memory (sp, tmp_buffer, 24); | |
0ec1e44d | 986 | #endif /* GENERIC_DUMMY_FRAMES */ |
41abdfbd | 987 | |
b112f2ae JK |
988 | /* set back chain properly */ |
989 | store_address (tmp_buffer, 4, saved_sp); | |
990 | write_memory (sp, tmp_buffer, 4); | |
41abdfbd | 991 | |
5f1c39ef | 992 | target_store_registers (-1); |
41abdfbd JG |
993 | return sp; |
994 | } | |
0ec1e44d MA |
995 | #ifdef ELF_OBJECT_FORMAT |
996 | ||
997 | /* Function: ppc_push_return_address (pc, sp) | |
998 | Set up the return address for the inferior function call. */ | |
999 | ||
1000 | CORE_ADDR | |
1001 | ppc_push_return_address (pc, sp) | |
1002 | CORE_ADDR pc; | |
1003 | CORE_ADDR sp; | |
1004 | { | |
1005 | write_register (LR_REGNUM, CALL_DUMMY_ADDRESS ()); | |
1006 | return sp; | |
1007 | } | |
1008 | ||
1009 | #endif | |
41abdfbd JG |
1010 | |
1011 | /* a given return value in `regbuf' with a type `valtype', extract and copy its | |
1012 | value into `valbuf' */ | |
1013 | ||
ecf4059f | 1014 | void |
41abdfbd | 1015 | extract_return_value (valtype, regbuf, valbuf) |
cd8a3d84 SS |
1016 | struct type *valtype; |
1017 | char regbuf[REGISTER_BYTES]; | |
1018 | char *valbuf; | |
41abdfbd | 1019 | { |
07781ac0 | 1020 | int offset = 0; |
41abdfbd JG |
1021 | |
1022 | if (TYPE_CODE (valtype) == TYPE_CODE_FLT) { | |
1023 | ||
1024 | double dd; float ff; | |
1025 | /* floats and doubles are returned in fpr1. fpr's have a size of 8 bytes. | |
1026 | We need to truncate the return value into float size (4 byte) if | |
1027 | necessary. */ | |
1028 | ||
1029 | if (TYPE_LENGTH (valtype) > 4) /* this is a double */ | |
75621b2b MS |
1030 | memcpy (valbuf, |
1031 | ®buf[REGISTER_BYTE (FP0_REGNUM + 1)], | |
1032 | TYPE_LENGTH (valtype)); | |
41abdfbd | 1033 | else { /* float */ |
ade40d31 | 1034 | memcpy (&dd, ®buf[REGISTER_BYTE (FP0_REGNUM + 1)], 8); |
41abdfbd | 1035 | ff = (float)dd; |
ade40d31 | 1036 | memcpy (valbuf, &ff, sizeof(float)); |
41abdfbd JG |
1037 | } |
1038 | } | |
07781ac0 | 1039 | else { |
41abdfbd | 1040 | /* return value is copied starting from r3. */ |
07781ac0 PS |
1041 | if (TARGET_BYTE_ORDER == BIG_ENDIAN |
1042 | && TYPE_LENGTH (valtype) < REGISTER_RAW_SIZE (3)) | |
1043 | offset = REGISTER_RAW_SIZE (3) - TYPE_LENGTH (valtype); | |
1044 | ||
75621b2b MS |
1045 | memcpy (valbuf, |
1046 | regbuf + REGISTER_BYTE (3) + offset, | |
07781ac0 PS |
1047 | TYPE_LENGTH (valtype)); |
1048 | } | |
41abdfbd JG |
1049 | } |
1050 | ||
1051 | ||
ecf4059f JG |
1052 | /* keep structure return address in this variable. |
1053 | FIXME: This is a horrid kludge which should not be allowed to continue | |
1054 | living. This only allows a single nested call to a structure-returning | |
1055 | function. Come on, guys! -- gnu@cygnus.com, Aug 92 */ | |
41abdfbd JG |
1056 | |
1057 | CORE_ADDR rs6000_struct_return_address; | |
1058 | ||
1059 | ||
c2e4669f JG |
1060 | /* Indirect function calls use a piece of trampoline code to do context |
1061 | switching, i.e. to set the new TOC table. Skip such code if we are on | |
1062 | its first instruction (as when we have single-stepped to here). | |
07aa9fdc PS |
1063 | Also skip shared library trampoline code (which is different from |
1064 | indirect function call trampolines). | |
c2e4669f JG |
1065 | Result is desired PC to step until, or NULL if we are not in |
1066 | trampoline code. */ | |
41abdfbd | 1067 | |
ecf4059f | 1068 | CORE_ADDR |
41abdfbd | 1069 | skip_trampoline_code (pc) |
cd8a3d84 | 1070 | CORE_ADDR pc; |
41abdfbd JG |
1071 | { |
1072 | register unsigned int ii, op; | |
07aa9fdc | 1073 | CORE_ADDR solib_target_pc; |
41abdfbd JG |
1074 | |
1075 | static unsigned trampoline_code[] = { | |
1076 | 0x800b0000, /* l r0,0x0(r11) */ | |
1077 | 0x90410014, /* st r2,0x14(r1) */ | |
1078 | 0x7c0903a6, /* mtctr r0 */ | |
1079 | 0x804b0004, /* l r2,0x4(r11) */ | |
1080 | 0x816b0008, /* l r11,0x8(r11) */ | |
1081 | 0x4e800420, /* bctr */ | |
1082 | 0x4e800020, /* br */ | |
1083 | 0 | |
1084 | }; | |
1085 | ||
07aa9fdc PS |
1086 | /* If pc is in a shared library trampoline, return its target. */ |
1087 | solib_target_pc = find_solib_trampoline_target (pc); | |
1088 | if (solib_target_pc) | |
1089 | return solib_target_pc; | |
1090 | ||
41abdfbd JG |
1091 | for (ii=0; trampoline_code[ii]; ++ii) { |
1092 | op = read_memory_integer (pc + (ii*4), 4); | |
1093 | if (op != trampoline_code [ii]) | |
359a097f | 1094 | return 0; |
41abdfbd JG |
1095 | } |
1096 | ii = read_register (11); /* r11 holds destination addr */ | |
1097 | pc = read_memory_integer (ii, 4); /* (r11) value */ | |
1098 | return pc; | |
1099 | } | |
1100 | ||
068c9fd6 | 1101 | /* Determines whether the function FI has a frame on the stack or not. */ |
cd8a3d84 | 1102 | |
ecf4059f | 1103 | int |
068c9fd6 MM |
1104 | frameless_function_invocation (fi) |
1105 | struct frame_info *fi; | |
ecf4059f JG |
1106 | { |
1107 | CORE_ADDR func_start; | |
63641491 | 1108 | struct rs6000_framedata fdata; |
ecf4059f | 1109 | |
4cc56716 PS |
1110 | /* Don't even think about framelessness except on the innermost frame |
1111 | or if the function was interrupted by a signal. */ | |
1112 | if (fi->next != NULL && !fi->next->signal_handler_caller) | |
b0e932ad JK |
1113 | return 0; |
1114 | ||
4cc56716 | 1115 | func_start = get_pc_function_start (fi->pc); |
ecf4059f JG |
1116 | |
1117 | /* If we failed to find the start of the function, it is a mistake | |
1118 | to inspect the instructions. */ | |
1119 | ||
1120 | if (!func_start) | |
4cc56716 PS |
1121 | { |
1122 | /* A frame with a zero PC is usually created by dereferencing a NULL | |
1123 | function pointer, normally causing an immediate core dump of the | |
1124 | inferior. Mark function as frameless, as the inferior has no chance | |
1125 | of setting up a stack frame. */ | |
1126 | if (fi->pc == 0) | |
1127 | return 1; | |
1128 | else | |
1129 | return 0; | |
1130 | } | |
ecf4059f | 1131 | |
068c9fd6 MM |
1132 | (void) skip_prologue (func_start, &fdata); |
1133 | return fdata.frameless; | |
ecf4059f JG |
1134 | } |
1135 | ||
068c9fd6 | 1136 | /* Return the PC saved in a frame */ |
cd8a3d84 | 1137 | |
068c9fd6 MM |
1138 | unsigned long |
1139 | frame_saved_pc (fi) | |
1140 | struct frame_info *fi; | |
1141 | { | |
1142 | CORE_ADDR func_start; | |
1143 | struct rs6000_framedata fdata; | |
068c9fd6 | 1144 | |
965dde97 PS |
1145 | if (fi->signal_handler_caller) |
1146 | return read_memory_integer (fi->frame + SIG_FRAME_PC_OFFSET, 4); | |
1147 | ||
0ec1e44d MA |
1148 | #ifdef USE_GENERIC_DUMMY_FRAMES |
1149 | if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) | |
1150 | return generic_read_register_dummy(fi->pc, fi->frame, PC_REGNUM); | |
1151 | #endif /* GENERIC_DUMMY_FRAMES */ | |
1152 | ||
86a51f41 | 1153 | func_start = get_pc_function_start (fi->pc); |
068c9fd6 MM |
1154 | |
1155 | /* If we failed to find the start of the function, it is a mistake | |
1156 | to inspect the instructions. */ | |
1157 | if (!func_start) | |
1158 | return 0; | |
1159 | ||
1160 | (void) skip_prologue (func_start, &fdata); | |
068c9fd6 | 1161 | |
4b4c6c96 | 1162 | if (fdata.lr_offset == 0 && fi->next != NULL) |
4cc56716 PS |
1163 | { |
1164 | if (fi->next->signal_handler_caller) | |
1165 | return read_memory_integer (fi->next->frame + SIG_FRAME_LR_OFFSET, 4); | |
1166 | else | |
1167 | return read_memory_integer (rs6000_frame_chain (fi) + DEFAULT_LR_SAVE, | |
1168 | 4); | |
1169 | } | |
4b4c6c96 MM |
1170 | |
1171 | if (fdata.lr_offset == 0) | |
1172 | return read_register (LR_REGNUM); | |
1173 | ||
068c9fd6 MM |
1174 | return read_memory_integer (rs6000_frame_chain (fi) + fdata.lr_offset, 4); |
1175 | } | |
ecf4059f JG |
1176 | |
1177 | /* If saved registers of frame FI are not known yet, read and cache them. | |
63641491 | 1178 | &FDATAP contains rs6000_framedata; TDATAP can be NULL, |
ecf4059f JG |
1179 | in which case the framedata are read. */ |
1180 | ||
1181 | static void | |
86a51f41 | 1182 | frame_get_saved_regs (fi, fdatap) |
ecf4059f | 1183 | struct frame_info *fi; |
63641491 | 1184 | struct rs6000_framedata *fdatap; |
ecf4059f JG |
1185 | { |
1186 | int ii; | |
1187 | CORE_ADDR frame_addr; | |
63641491 | 1188 | struct rs6000_framedata work_fdata; |
ecf4059f | 1189 | |
86a51f41 | 1190 | if (fi->saved_regs) |
ecf4059f JG |
1191 | return; |
1192 | ||
86a51f41 AC |
1193 | if (fdatap == NULL) |
1194 | { | |
1195 | fdatap = &work_fdata; | |
1196 | (void) skip_prologue (get_pc_function_start (fi->pc), fdatap); | |
1197 | } | |
1198 | ||
1199 | frame_saved_regs_zalloc (fi); | |
ecf4059f | 1200 | |
86a51f41 AC |
1201 | /* If there were any saved registers, figure out parent's stack |
1202 | pointer. */ | |
1203 | /* The following is true only if the frame doesn't have a call to | |
1204 | alloca(), FIXME. */ | |
ecf4059f | 1205 | |
86a51f41 AC |
1206 | if (fdatap->saved_fpr == 0 && fdatap->saved_gpr == 0 |
1207 | && fdatap->lr_offset == 0 && fdatap->cr_offset == 0) | |
1208 | frame_addr = 0; | |
1209 | else if (fi->prev && fi->prev->frame) | |
ecf4059f JG |
1210 | frame_addr = fi->prev->frame; |
1211 | else | |
1212 | frame_addr = read_memory_integer (fi->frame, 4); | |
1213 | ||
1214 | /* if != -1, fdatap->saved_fpr is the smallest number of saved_fpr. | |
965dde97 | 1215 | All fpr's from saved_fpr to fp31 are saved. */ |
ecf4059f | 1216 | |
86a51f41 AC |
1217 | if (fdatap->saved_fpr >= 0) |
1218 | { | |
1219 | int i; | |
1220 | int fpr_offset = frame_addr + fdatap->fpr_offset; | |
1221 | for (i = fdatap->saved_fpr; i < 32; i++) | |
1222 | { | |
1223 | fi->saved_regs [FP0_REGNUM + i] = fpr_offset; | |
1224 | fpr_offset += 8; | |
1225 | } | |
965dde97 | 1226 | } |
ecf4059f JG |
1227 | |
1228 | /* if != -1, fdatap->saved_gpr is the smallest number of saved_gpr. | |
965dde97 | 1229 | All gpr's from saved_gpr to gpr31 are saved. */ |
86a51f41 AC |
1230 | |
1231 | if (fdatap->saved_gpr >= 0) | |
1232 | { | |
1233 | int i; | |
1234 | int gpr_offset = frame_addr + fdatap->gpr_offset; | |
1235 | for (i = fdatap->saved_gpr; i < 32; i++) | |
1236 | { | |
1237 | fi->saved_regs [i] = gpr_offset; | |
1238 | gpr_offset += 4; | |
1239 | } | |
965dde97 | 1240 | } |
965dde97 PS |
1241 | |
1242 | /* If != 0, fdatap->cr_offset is the offset from the frame that holds | |
1243 | the CR. */ | |
1244 | if (fdatap->cr_offset != 0) | |
86a51f41 | 1245 | fi->saved_regs [CR_REGNUM] = frame_addr + fdatap->cr_offset; |
965dde97 PS |
1246 | |
1247 | /* If != 0, fdatap->lr_offset is the offset from the frame that holds | |
1248 | the LR. */ | |
1249 | if (fdatap->lr_offset != 0) | |
86a51f41 | 1250 | fi->saved_regs [LR_REGNUM] = frame_addr + fdatap->lr_offset; |
ecf4059f JG |
1251 | } |
1252 | ||
1253 | /* Return the address of a frame. This is the inital %sp value when the frame | |
1254 | was first allocated. For functions calling alloca(), it might be saved in | |
1255 | an alloca register. */ | |
1256 | ||
86a51f41 | 1257 | static CORE_ADDR |
ecf4059f JG |
1258 | frame_initial_stack_address (fi) |
1259 | struct frame_info *fi; | |
1260 | { | |
1261 | CORE_ADDR tmpaddr; | |
63641491 | 1262 | struct rs6000_framedata fdata; |
ecf4059f JG |
1263 | struct frame_info *callee_fi; |
1264 | ||
1265 | /* if the initial stack pointer (frame address) of this frame is known, | |
1266 | just return it. */ | |
1267 | ||
86a51f41 AC |
1268 | if (fi->extra_info->initial_sp) |
1269 | return fi->extra_info->initial_sp; | |
ecf4059f JG |
1270 | |
1271 | /* find out if this function is using an alloca register.. */ | |
1272 | ||
068c9fd6 | 1273 | (void) skip_prologue (get_pc_function_start (fi->pc), &fdata); |
ecf4059f JG |
1274 | |
1275 | /* if saved registers of this frame are not known yet, read and cache them. */ | |
1276 | ||
86a51f41 AC |
1277 | if (!fi->saved_regs) |
1278 | frame_get_saved_regs (fi, &fdata); | |
ecf4059f JG |
1279 | |
1280 | /* If no alloca register used, then fi->frame is the value of the %sp for | |
1281 | this frame, and it is good enough. */ | |
1282 | ||
86a51f41 AC |
1283 | if (fdata.alloca_reg < 0) |
1284 | { | |
1285 | fi->extra_info->initial_sp = fi->frame; | |
1286 | return fi->extra_info->initial_sp; | |
1287 | } | |
ecf4059f JG |
1288 | |
1289 | /* This function has an alloca register. If this is the top-most frame | |
1290 | (with the lowest address), the value in alloca register is good. */ | |
1291 | ||
1292 | if (!fi->next) | |
86a51f41 | 1293 | return fi->extra_info->initial_sp = read_register (fdata.alloca_reg); |
ecf4059f JG |
1294 | |
1295 | /* Otherwise, this is a caller frame. Callee has usually already saved | |
1296 | registers, but there are exceptions (such as when the callee | |
1297 | has no parameters). Find the address in which caller's alloca | |
1298 | register is saved. */ | |
1299 | ||
1300 | for (callee_fi = fi->next; callee_fi; callee_fi = callee_fi->next) { | |
1301 | ||
86a51f41 AC |
1302 | if (!callee_fi->saved_regs) |
1303 | frame_get_saved_regs (callee_fi, NULL); | |
ecf4059f JG |
1304 | |
1305 | /* this is the address in which alloca register is saved. */ | |
1306 | ||
86a51f41 | 1307 | tmpaddr = callee_fi->saved_regs [fdata.alloca_reg]; |
ecf4059f | 1308 | if (tmpaddr) { |
86a51f41 AC |
1309 | fi->extra_info->initial_sp = read_memory_integer (tmpaddr, 4); |
1310 | return fi->extra_info->initial_sp; | |
ecf4059f JG |
1311 | } |
1312 | ||
1313 | /* Go look into deeper levels of the frame chain to see if any one of | |
1314 | the callees has saved alloca register. */ | |
1315 | } | |
1316 | ||
1317 | /* If alloca register was not saved, by the callee (or any of its callees) | |
1318 | then the value in the register is still good. */ | |
1319 | ||
86a51f41 AC |
1320 | fi->extra_info->initial_sp = read_register (fdata.alloca_reg); |
1321 | return fi->extra_info->initial_sp; | |
ecf4059f JG |
1322 | } |
1323 | ||
669caa9c | 1324 | CORE_ADDR |
f3649227 JK |
1325 | rs6000_frame_chain (thisframe) |
1326 | struct frame_info *thisframe; | |
1327 | { | |
669caa9c | 1328 | CORE_ADDR fp; |
0ec1e44d MA |
1329 | |
1330 | #ifdef USE_GENERIC_DUMMY_FRAMES | |
1331 | if (PC_IN_CALL_DUMMY (thisframe->pc, thisframe->frame, thisframe->frame)) | |
1332 | return thisframe->frame; /* dummy frame same as caller's frame */ | |
1333 | #endif /* GENERIC_DUMMY_FRAMES */ | |
1334 | ||
1335 | if (inside_entry_file (thisframe->pc) || | |
1336 | thisframe->pc == entry_point_address ()) | |
f3649227 | 1337 | return 0; |
0ec1e44d | 1338 | |
cee86be3 | 1339 | if (thisframe->signal_handler_caller) |
9ed8604f | 1340 | fp = read_memory_integer (thisframe->frame + SIG_FRAME_FP_OFFSET, 4); |
4cc56716 PS |
1341 | else if (thisframe->next != NULL |
1342 | && thisframe->next->signal_handler_caller | |
1343 | && frameless_function_invocation (thisframe)) | |
1344 | /* A frameless function interrupted by a signal did not change the | |
1345 | frame pointer. */ | |
1346 | fp = FRAME_FP (thisframe); | |
cee86be3 JK |
1347 | else |
1348 | fp = read_memory_integer ((thisframe)->frame, 4); | |
1349 | ||
0ec1e44d MA |
1350 | #ifdef USE_GENERIC_DUMMY_FRAMES |
1351 | { | |
1352 | CORE_ADDR fpp, lr; | |
1353 | ||
1354 | lr = read_register (LR_REGNUM); | |
1355 | if (lr == entry_point_address ()) | |
1356 | if (fp != 0 && (fpp = read_memory_integer (fp, 4)) != 0) | |
1357 | if (PC_IN_CALL_DUMMY (lr, fpp, fpp)) | |
1358 | return fpp; | |
1359 | } | |
1360 | #endif /* GENERIC_DUMMY_FRAMES */ | |
f3649227 JK |
1361 | return fp; |
1362 | } | |
ecf4059f | 1363 | \f |
65eaea27 JL |
1364 | /* Return nonzero if ADDR (a function pointer) is in the data space and |
1365 | is therefore a special function pointer. */ | |
1366 | ||
1367 | int | |
1368 | is_magic_function_pointer (addr) | |
1369 | CORE_ADDR addr; | |
1370 | { | |
1371 | struct obj_section *s; | |
1372 | ||
1373 | s = find_pc_section (addr); | |
1374 | if (s && s->the_bfd_section->flags & SEC_CODE) | |
1375 | return 0; | |
1376 | else | |
1377 | return 1; | |
1378 | } | |
1379 | ||
5c172b4b MM |
1380 | #ifdef GDB_TARGET_POWERPC |
1381 | int | |
1382 | gdb_print_insn_powerpc (memaddr, info) | |
1383 | bfd_vma memaddr; | |
1384 | disassemble_info *info; | |
1385 | { | |
1386 | if (TARGET_BYTE_ORDER == BIG_ENDIAN) | |
1387 | return print_insn_big_powerpc (memaddr, info); | |
1388 | else | |
1389 | return print_insn_little_powerpc (memaddr, info); | |
1390 | } | |
1391 | #endif | |
1392 | ||
0ec1e44d MA |
1393 | /* Function: get_saved_register |
1394 | Just call the generic_get_saved_register function. */ | |
1395 | ||
70423641 | 1396 | #ifdef USE_GENERIC_DUMMY_FRAMES |
0ec1e44d MA |
1397 | void |
1398 | get_saved_register (raw_buffer, optimized, addrp, frame, regnum, lval) | |
1399 | char *raw_buffer; | |
1400 | int *optimized; | |
1401 | CORE_ADDR *addrp; | |
1402 | struct frame_info *frame; | |
1403 | int regnum; | |
1404 | enum lval_type *lval; | |
1405 | { | |
1406 | generic_get_saved_register (raw_buffer, optimized, addrp, | |
1407 | frame, regnum, lval); | |
1408 | } | |
70423641 | 1409 | #endif |
0ec1e44d MA |
1410 | |
1411 | ||
18b46e7c SS |
1412 | void |
1413 | _initialize_rs6000_tdep () | |
1414 | { | |
1415 | /* FIXME, this should not be decided via ifdef. */ | |
1416 | #ifdef GDB_TARGET_POWERPC | |
5c172b4b | 1417 | tm_print_insn = gdb_print_insn_powerpc; |
18b46e7c SS |
1418 | #else |
1419 | tm_print_insn = print_insn_rs6000; | |
1420 | #endif | |
1421 | } |