Commit | Line | Data |
---|---|---|
41abdfbd | 1 | /* Target-dependent code for GDB, the GNU debugger. |
18b46e7c | 2 | Copyright 1986, 1987, 1989, 1991, 1992, 1993, 1994, 1995 |
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 | |
19 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
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" |
41abdfbd | 27 | |
2aefe6e4 JK |
28 | #include "xcoffsolib.h" |
29 | ||
41abdfbd | 30 | #include <a.out.h> |
d6434f39 JG |
31 | |
32 | extern struct obstack frame_cache_obstack; | |
33 | ||
41abdfbd | 34 | extern int errno; |
41abdfbd JG |
35 | |
36 | /* Nonzero if we just simulated a single step break. */ | |
37 | int one_stepped; | |
38 | ||
41abdfbd JG |
39 | /* Breakpoint shadows for the single step instructions will be kept here. */ |
40 | ||
41 | static struct sstep_breaks { | |
030fb5cb JK |
42 | /* Address, or 0 if this is not in use. */ |
43 | CORE_ADDR address; | |
44 | /* Shadow contents. */ | |
45 | char data[4]; | |
41abdfbd JG |
46 | } stepBreaks[2]; |
47 | ||
ecf4059f JG |
48 | /* Static function prototypes */ |
49 | ||
ecf4059f JG |
50 | static CORE_ADDR |
51 | find_toc_address PARAMS ((CORE_ADDR pc)); | |
52 | ||
53 | static CORE_ADDR | |
54 | branch_dest PARAMS ((int opcode, int instr, CORE_ADDR pc, CORE_ADDR safety)); | |
55 | ||
56 | static void | |
57 | frame_get_cache_fsr PARAMS ((struct frame_info *fi, | |
63641491 | 58 | struct rs6000_framedata *fdatap)); |
41abdfbd JG |
59 | |
60 | /* | |
61 | * Calculate the destination of a branch/jump. Return -1 if not a branch. | |
62 | */ | |
ecf4059f | 63 | static CORE_ADDR |
41abdfbd | 64 | branch_dest (opcode, instr, pc, safety) |
ecf4059f JG |
65 | int opcode; |
66 | int instr; | |
67 | CORE_ADDR pc; | |
68 | CORE_ADDR safety; | |
41abdfbd JG |
69 | { |
70 | register long offset; | |
ecf4059f | 71 | CORE_ADDR dest; |
41abdfbd JG |
72 | int immediate; |
73 | int absolute; | |
74 | int ext_op; | |
75 | ||
76 | absolute = (int) ((instr >> 1) & 1); | |
77 | ||
78 | switch (opcode) { | |
79 | case 18 : | |
ecf4059f | 80 | immediate = ((instr & ~3) << 6) >> 6; /* br unconditional */ |
dc59e982 MM |
81 | if (absolute) |
82 | dest = immediate; | |
83 | else | |
84 | dest = pc + immediate; | |
85 | break; | |
41abdfbd JG |
86 | |
87 | case 16 : | |
dc59e982 | 88 | immediate = ((instr & ~3) << 16) >> 16; /* br conditional */ |
41abdfbd JG |
89 | if (absolute) |
90 | dest = immediate; | |
91 | else | |
92 | dest = pc + immediate; | |
93 | break; | |
94 | ||
95 | case 19 : | |
96 | ext_op = (instr>>1) & 0x3ff; | |
97 | ||
98 | if (ext_op == 16) /* br conditional register */ | |
99 | dest = read_register (LR_REGNUM) & ~3; | |
100 | ||
101 | else if (ext_op == 528) /* br cond to count reg */ | |
9aa31e91 JK |
102 | { |
103 | dest = read_register (CTR_REGNUM) & ~3; | |
104 | ||
105 | /* If we are about to execute a system call, dest is something | |
106 | like 0x22fc or 0x3b00. Upon completion the system call | |
107 | will return to the address in the link register. */ | |
108 | if (dest < TEXT_SEGMENT_BASE) | |
109 | dest = read_register (LR_REGNUM) & ~3; | |
110 | } | |
41abdfbd JG |
111 | else return -1; |
112 | break; | |
113 | ||
114 | default: return -1; | |
115 | } | |
818de002 | 116 | return (dest < TEXT_SEGMENT_BASE) ? safety : dest; |
41abdfbd JG |
117 | } |
118 | ||
119 | ||
120 | ||
121 | /* AIX does not support PT_STEP. Simulate it. */ | |
122 | ||
997cc2c0 | 123 | void |
41abdfbd | 124 | single_step (signal) |
997cc2c0 | 125 | int signal; |
41abdfbd JG |
126 | { |
127 | #define INSNLEN(OPCODE) 4 | |
128 | ||
5c172b4b MM |
129 | static char le_breakp[] = LITTLE_BREAKPOINT; |
130 | static char be_breakp[] = BIG_BREAKPOINT; | |
131 | char *breakp = TARGET_BYTE_ORDER == BIG_ENDIAN ? be_breakp : le_breakp; | |
030fb5cb JK |
132 | int ii, insn; |
133 | CORE_ADDR loc; | |
134 | CORE_ADDR breaks[2]; | |
135 | int opcode; | |
41abdfbd JG |
136 | |
137 | if (!one_stepped) { | |
41abdfbd JG |
138 | loc = read_pc (); |
139 | ||
b112f2ae | 140 | insn = read_memory_integer (loc, 4); |
41abdfbd JG |
141 | |
142 | breaks[0] = loc + INSNLEN(insn); | |
143 | opcode = insn >> 26; | |
144 | breaks[1] = branch_dest (opcode, insn, loc, breaks[0]); | |
145 | ||
818de002 PB |
146 | /* Don't put two breakpoints on the same address. */ |
147 | if (breaks[1] == breaks[0]) | |
148 | breaks[1] = -1; | |
149 | ||
030fb5cb | 150 | stepBreaks[1].address = 0; |
41abdfbd JG |
151 | |
152 | for (ii=0; ii < 2; ++ii) { | |
153 | ||
154 | /* ignore invalid breakpoint. */ | |
155 | if ( breaks[ii] == -1) | |
156 | continue; | |
157 | ||
030fb5cb | 158 | read_memory (breaks[ii], stepBreaks[ii].data, 4); |
41abdfbd | 159 | |
030fb5cb | 160 | write_memory (breaks[ii], breakp, 4); |
41abdfbd JG |
161 | stepBreaks[ii].address = breaks[ii]; |
162 | } | |
163 | ||
164 | one_stepped = 1; | |
997cc2c0 | 165 | } else { |
41abdfbd JG |
166 | |
167 | /* remove step breakpoints. */ | |
168 | for (ii=0; ii < 2; ++ii) | |
030fb5cb | 169 | if (stepBreaks[ii].address != 0) |
41abdfbd | 170 | write_memory |
030fb5cb | 171 | (stepBreaks[ii].address, stepBreaks[ii].data, 4); |
41abdfbd JG |
172 | |
173 | one_stepped = 0; | |
174 | } | |
997cc2c0 | 175 | errno = 0; /* FIXME, don't ignore errors! */ |
030fb5cb | 176 | /* What errors? {read,write}_memory call error(). */ |
41abdfbd | 177 | } |
41abdfbd JG |
178 | |
179 | ||
180 | /* return pc value after skipping a function prologue. */ | |
181 | ||
182 | skip_prologue (pc) | |
ecf4059f | 183 | CORE_ADDR pc; |
41abdfbd | 184 | { |
34df79fc | 185 | char buf[4]; |
41abdfbd | 186 | unsigned int tmp; |
34df79fc | 187 | unsigned long op; |
41abdfbd | 188 | |
34df79fc | 189 | if (target_read_memory (pc, buf, 4)) |
41abdfbd | 190 | return pc; /* Can't access it -- assume no prologue. */ |
34df79fc | 191 | op = extract_unsigned_integer (buf, 4); |
41abdfbd JG |
192 | |
193 | /* Assume that subsequent fetches can fail with low probability. */ | |
194 | ||
195 | if (op == 0x7c0802a6) { /* mflr r0 */ | |
196 | pc += 4; | |
197 | op = read_memory_integer (pc, 4); | |
198 | } | |
41abdfbd JG |
199 | |
200 | if ((op & 0xfc00003e) == 0x7c000026) { /* mfcr Rx */ | |
201 | pc += 4; | |
202 | op = read_memory_integer (pc, 4); | |
203 | } | |
204 | ||
205 | if ((op & 0xfc000000) == 0x48000000) { /* bl foo, to save fprs??? */ | |
206 | pc += 4; | |
207 | op = read_memory_integer (pc, 4); | |
1eeba686 PB |
208 | |
209 | /* At this point, make sure this is not a trampoline function | |
210 | (a function that simply calls another functions, and nothing else). | |
211 | If the next is not a nop, this branch was part of the function | |
212 | prologue. */ | |
213 | ||
629b6214 | 214 | if (op == 0x4def7b82 || /* crorc 15, 15, 15 */ |
1eeba686 | 215 | op == 0x0) |
629b6214 | 216 | return pc - 4; /* don't skip over this branch */ |
41abdfbd JG |
217 | } |
218 | ||
629b6214 MM |
219 | if ((op & 0xfc1f0000) == 0xd8010000) { /* stfd Rx,NUM(r1) */ |
220 | pc += 4; /* store floating register double */ | |
cdb1cc92 ILT |
221 | op = read_memory_integer (pc, 4); |
222 | } | |
223 | ||
629b6214 | 224 | if ((op & 0xfc1f0000) == 0xbc010000) { /* stm Rx, NUM(r1) */ |
41abdfbd JG |
225 | pc += 4; |
226 | op = read_memory_integer (pc, 4); | |
227 | } | |
228 | ||
e137e850 | 229 | while ((op & 0xfc1f0000) == 0x90010000 && /* st rx,NUM(r1), rx >= r13 */ |
629b6214 MM |
230 | (op & 0x03e00000) >= 0x01a00000) { |
231 | pc += 4; | |
232 | op = read_memory_integer (pc, 4); | |
233 | } | |
e137e850 PS |
234 | |
235 | if (op == 0x90010008) { /* st r0,8(r1) */ | |
236 | pc += 4; | |
237 | op = read_memory_integer (pc, 4); | |
238 | } | |
239 | ||
240 | if (op == 0x91810004) { /* st r12,4(r1) */ | |
241 | pc += 4; | |
242 | op = read_memory_integer (pc, 4); | |
243 | } | |
629b6214 | 244 | |
e137e850 | 245 | if ((op & 0xffff0000) == 0x94210000) { /* stu r1,NUM(r1) */ |
41abdfbd JG |
246 | pc += 4; |
247 | op = read_memory_integer (pc, 4); | |
248 | } | |
249 | ||
250 | while ((tmp = (op >> 22)) == 0x20f) { /* l r31, ... or */ | |
251 | pc += 4; /* l r30, ... */ | |
252 | op = read_memory_integer (pc, 4); | |
253 | } | |
254 | ||
507e4004 | 255 | /* store parameters into stack */ |
818de002 PB |
256 | while( |
257 | (op & 0xfc1f0000) == 0xd8010000 || /* stfd Rx,NUM(r1) */ | |
258 | (op & 0xfc1f0000) == 0x90010000 || /* st r?, NUM(r1) */ | |
259 | (op & 0xfc000000) == 0xfc000000 || /* frsp, fp?, .. */ | |
260 | (op & 0xd0000000) == 0xd0000000) /* stfs, fp?, .. */ | |
261 | { | |
262 | pc += 4; /* store fpr double */ | |
263 | op = read_memory_integer (pc, 4); | |
264 | } | |
41abdfbd | 265 | |
d2985684 PS |
266 | if (op == 0x603f0000 /* oril r31, r1, 0x0 */ |
267 | || op == 0x7c3f0b78) { /* mr r31, r1 */ | |
41abdfbd JG |
268 | pc += 4; /* this happens if r31 is used as */ |
269 | op = read_memory_integer (pc, 4); /* frame ptr. (gcc does that) */ | |
270 | ||
818de002 PB |
271 | tmp = 0; |
272 | while ((op >> 16) == (0x907f + tmp)) { /* st r3, NUM(r31) */ | |
273 | pc += 4; /* st r4, NUM(r31), ... */ | |
41abdfbd | 274 | op = read_memory_integer (pc, 4); |
818de002 | 275 | tmp += 0x20; |
41abdfbd JG |
276 | } |
277 | } | |
507e4004 PB |
278 | #if 0 |
279 | /* I have problems with skipping over __main() that I need to address | |
280 | * sometime. Previously, I used to use misc_function_vector which | |
281 | * didn't work as well as I wanted to be. -MGO */ | |
282 | ||
283 | /* If the first thing after skipping a prolog is a branch to a function, | |
284 | this might be a call to an initializer in main(), introduced by gcc2. | |
285 | We'd like to skip over it as well. Fortunately, xlc does some extra | |
286 | work before calling a function right after a prologue, thus we can | |
287 | single out such gcc2 behaviour. */ | |
288 | ||
289 | ||
290 | if ((op & 0xfc000001) == 0x48000001) { /* bl foo, an initializer function? */ | |
291 | op = read_memory_integer (pc+4, 4); | |
292 | ||
293 | if (op == 0x4def7b82) { /* cror 0xf, 0xf, 0xf (nop) */ | |
294 | ||
295 | /* check and see if we are in main. If so, skip over this initializer | |
296 | function as well. */ | |
297 | ||
298 | tmp = find_pc_misc_function (pc); | |
2e4964ad | 299 | if (tmp >= 0 && STREQ (misc_function_vector [tmp].name, "main")) |
507e4004 PB |
300 | return pc + 8; |
301 | } | |
302 | } | |
303 | #endif /* 0 */ | |
304 | ||
41abdfbd JG |
305 | return pc; |
306 | } | |
307 | ||
818de002 | 308 | |
41abdfbd JG |
309 | /************************************************************************* |
310 | Support for creating pushind a dummy frame into the stack, and popping | |
311 | frames, etc. | |
312 | *************************************************************************/ | |
313 | ||
818de002 PB |
314 | /* The total size of dummy frame is 436, which is; |
315 | ||
316 | 32 gpr's - 128 bytes | |
317 | 32 fpr's - 256 " | |
318 | 7 the rest - 28 " | |
319 | and 24 extra bytes for the callee's link area. The last 24 bytes | |
320 | for the link area might not be necessary, since it will be taken | |
321 | care of by push_arguments(). */ | |
322 | ||
323 | #define DUMMY_FRAME_SIZE 436 | |
324 | ||
41abdfbd JG |
325 | #define DUMMY_FRAME_ADDR_SIZE 10 |
326 | ||
327 | /* Make sure you initialize these in somewhere, in case gdb gives up what it | |
818de002 | 328 | was debugging and starts debugging something else. FIXMEibm */ |
41abdfbd JG |
329 | |
330 | static int dummy_frame_count = 0; | |
331 | static int dummy_frame_size = 0; | |
332 | static CORE_ADDR *dummy_frame_addr = 0; | |
333 | ||
334 | extern int stop_stack_dummy; | |
335 | ||
336 | /* push a dummy frame into stack, save all register. Currently we are saving | |
337 | only gpr's and fpr's, which is not good enough! FIXMEmgo */ | |
338 | ||
ecf4059f | 339 | void |
41abdfbd JG |
340 | push_dummy_frame () |
341 | { | |
359a097f JK |
342 | /* stack pointer. */ |
343 | CORE_ADDR sp; | |
b112f2ae JK |
344 | /* Same thing, target byte order. */ |
345 | char sp_targ[4]; | |
359a097f JK |
346 | |
347 | /* link register. */ | |
348 | CORE_ADDR pc; | |
349 | /* Same thing, target byte order. */ | |
350 | char pc_targ[4]; | |
351 | ||
41abdfbd JG |
352 | int ii; |
353 | ||
5f1c39ef | 354 | target_fetch_registers (-1); |
6c6afbb9 | 355 | |
41abdfbd JG |
356 | if (dummy_frame_count >= dummy_frame_size) { |
357 | dummy_frame_size += DUMMY_FRAME_ADDR_SIZE; | |
358 | if (dummy_frame_addr) | |
359 | dummy_frame_addr = (CORE_ADDR*) xrealloc | |
360 | (dummy_frame_addr, sizeof(CORE_ADDR) * (dummy_frame_size)); | |
361 | else | |
362 | dummy_frame_addr = (CORE_ADDR*) | |
363 | xmalloc (sizeof(CORE_ADDR) * (dummy_frame_size)); | |
364 | } | |
365 | ||
366 | sp = read_register(SP_REGNUM); | |
359a097f | 367 | pc = read_register(PC_REGNUM); |
5816555b | 368 | store_address (pc_targ, 4, pc); |
41abdfbd JG |
369 | |
370 | dummy_frame_addr [dummy_frame_count++] = sp; | |
371 | ||
372 | /* Be careful! If the stack pointer is not decremented first, then kernel | |
6c6afbb9 | 373 | thinks he is free to use the space underneath it. And kernel actually |
41abdfbd JG |
374 | uses that area for IPC purposes when executing ptrace(2) calls. So |
375 | before writing register values into the new frame, decrement and update | |
376 | %sp first in order to secure your frame. */ | |
377 | ||
818de002 | 378 | write_register (SP_REGNUM, sp-DUMMY_FRAME_SIZE); |
41abdfbd | 379 | |
41abdfbd JG |
380 | /* gdb relies on the state of current_frame. We'd better update it, |
381 | otherwise things like do_registers_info() wouldn't work properly! */ | |
382 | ||
383 | flush_cached_frames (); | |
41abdfbd JG |
384 | |
385 | /* save program counter in link register's space. */ | |
359a097f | 386 | write_memory (sp+8, pc_targ, 4); |
41abdfbd | 387 | |
6c6afbb9 | 388 | /* save all floating point and general purpose registers here. */ |
41abdfbd JG |
389 | |
390 | /* fpr's, f0..f31 */ | |
391 | for (ii = 0; ii < 32; ++ii) | |
392 | write_memory (sp-8-(ii*8), ®isters[REGISTER_BYTE (31-ii+FP0_REGNUM)], 8); | |
393 | ||
394 | /* gpr's r0..r31 */ | |
395 | for (ii=1; ii <=32; ++ii) | |
396 | write_memory (sp-256-(ii*4), ®isters[REGISTER_BYTE (32-ii)], 4); | |
397 | ||
818de002 PB |
398 | /* so far, 32*2 + 32 words = 384 bytes have been written. |
399 | 7 extra registers in our register set: pc, ps, cnd, lr, cnt, xer, mq */ | |
400 | ||
401 | for (ii=1; ii <= (LAST_SP_REGNUM-FIRST_SP_REGNUM+1); ++ii) { | |
402 | write_memory (sp-384-(ii*4), | |
403 | ®isters[REGISTER_BYTE (FPLAST_REGNUM + ii)], 4); | |
404 | } | |
405 | ||
406 | /* Save sp or so called back chain right here. */ | |
b112f2ae JK |
407 | store_address (sp_targ, 4, sp); |
408 | write_memory (sp-DUMMY_FRAME_SIZE, sp_targ, 4); | |
818de002 | 409 | sp -= DUMMY_FRAME_SIZE; |
41abdfbd JG |
410 | |
411 | /* And finally, this is the back chain. */ | |
359a097f | 412 | write_memory (sp+8, pc_targ, 4); |
41abdfbd JG |
413 | } |
414 | ||
415 | ||
416 | /* Pop a dummy frame. | |
417 | ||
418 | In rs6000 when we push a dummy frame, we save all of the registers. This | |
419 | is usually done before user calls a function explicitly. | |
420 | ||
818de002 PB |
421 | After a dummy frame is pushed, some instructions are copied into stack, |
422 | and stack pointer is decremented even more. Since we don't have a frame | |
423 | pointer to get back to the parent frame of the dummy, we start having | |
424 | trouble poping it. Therefore, we keep a dummy frame stack, keeping | |
425 | addresses of dummy frames as such. When poping happens and when we | |
426 | detect that was a dummy frame, we pop it back to its parent by using | |
427 | dummy frame stack (`dummy_frame_addr' array). | |
ecf4059f JG |
428 | |
429 | FIXME: This whole concept is broken. You should be able to detect | |
430 | a dummy stack frame *on the user's stack itself*. When you do, | |
431 | then you know the format of that stack frame -- including its | |
432 | saved SP register! There should *not* be a separate stack in the | |
d6434f39 | 433 | GDB process that keeps track of these dummy frames! -- gnu@cygnus.com Aug92 |
41abdfbd JG |
434 | */ |
435 | ||
436 | pop_dummy_frame () | |
437 | { | |
438 | CORE_ADDR sp, pc; | |
439 | int ii; | |
440 | sp = dummy_frame_addr [--dummy_frame_count]; | |
441 | ||
442 | /* restore all fpr's. */ | |
443 | for (ii = 1; ii <= 32; ++ii) | |
444 | read_memory (sp-(ii*8), ®isters[REGISTER_BYTE (32-ii+FP0_REGNUM)], 8); | |
445 | ||
446 | /* restore all gpr's */ | |
447 | for (ii=1; ii <= 32; ++ii) { | |
448 | read_memory (sp-256-(ii*4), ®isters[REGISTER_BYTE (32-ii)], 4); | |
449 | } | |
450 | ||
818de002 PB |
451 | /* restore the rest of the registers. */ |
452 | for (ii=1; ii <=(LAST_SP_REGNUM-FIRST_SP_REGNUM+1); ++ii) | |
453 | read_memory (sp-384-(ii*4), | |
454 | ®isters[REGISTER_BYTE (FPLAST_REGNUM + ii)], 4); | |
455 | ||
456 | read_memory (sp-(DUMMY_FRAME_SIZE-8), | |
457 | ®isters [REGISTER_BYTE(PC_REGNUM)], 4); | |
41abdfbd JG |
458 | |
459 | /* when a dummy frame was being pushed, we had to decrement %sp first, in | |
460 | order to secure astack space. Thus, saved %sp (or %r1) value, is not the | |
461 | one we should restore. Change it with the one we need. */ | |
462 | ||
463 | *(int*)®isters [REGISTER_BYTE(FP_REGNUM)] = sp; | |
464 | ||
465 | /* Now we can restore all registers. */ | |
466 | ||
5f1c39ef | 467 | target_store_registers (-1); |
41abdfbd JG |
468 | pc = read_pc (); |
469 | flush_cached_frames (); | |
41abdfbd JG |
470 | } |
471 | ||
472 | ||
473 | /* pop the innermost frame, go back to the caller. */ | |
474 | ||
ecf4059f | 475 | void |
41abdfbd JG |
476 | pop_frame () |
477 | { | |
359a097f | 478 | CORE_ADDR pc, lr, sp, prev_sp; /* %pc, %lr, %sp */ |
63641491 | 479 | struct rs6000_framedata fdata; |
669caa9c | 480 | struct frame_info *frame = get_current_frame (); |
41abdfbd | 481 | int addr, ii; |
41abdfbd JG |
482 | |
483 | pc = read_pc (); | |
669caa9c | 484 | sp = FRAME_FP (frame); |
41abdfbd JG |
485 | |
486 | if (stop_stack_dummy && dummy_frame_count) { | |
487 | pop_dummy_frame (); | |
488 | return; | |
489 | } | |
490 | ||
07aa9fdc PS |
491 | /* Make sure that all registers are valid. */ |
492 | read_register_bytes (0, NULL, REGISTER_BYTES); | |
493 | ||
41abdfbd JG |
494 | /* figure out previous %pc value. If the function is frameless, it is |
495 | still in the link register, otherwise walk the frames and retrieve the | |
496 | saved %pc value in the previous frame. */ | |
497 | ||
34a1a3bf | 498 | addr = get_pc_function_start (frame->pc) + FUNCTION_START_OFFSET; |
6c6afbb9 | 499 | function_frame_info (addr, &fdata); |
41abdfbd | 500 | |
6c6afbb9 | 501 | if (fdata.frameless) |
07aa9fdc PS |
502 | prev_sp = sp; |
503 | else | |
504 | prev_sp = read_memory_integer (sp, 4); | |
505 | if (fdata.nosavedpc) | |
41abdfbd JG |
506 | lr = read_register (LR_REGNUM); |
507 | else | |
359a097f | 508 | lr = read_memory_integer (prev_sp+8, 4); |
41abdfbd JG |
509 | |
510 | /* reset %pc value. */ | |
511 | write_register (PC_REGNUM, lr); | |
512 | ||
513 | /* reset register values if any was saved earlier. */ | |
6c6afbb9 | 514 | addr = prev_sp - fdata.offset; |
41abdfbd | 515 | |
6c6afbb9 | 516 | if (fdata.saved_gpr != -1) |
669caa9c | 517 | for (ii = fdata.saved_gpr; ii <= 31; ++ii) { |
41abdfbd | 518 | read_memory (addr, ®isters [REGISTER_BYTE (ii)], 4); |
cdb1cc92 | 519 | addr += 4; |
41abdfbd JG |
520 | } |
521 | ||
6c6afbb9 | 522 | if (fdata.saved_fpr != -1) |
669caa9c | 523 | for (ii = fdata.saved_fpr; ii <= 31; ++ii) { |
41abdfbd JG |
524 | read_memory (addr, ®isters [REGISTER_BYTE (ii+FP0_REGNUM)], 8); |
525 | addr += 8; | |
526 | } | |
527 | ||
528 | write_register (SP_REGNUM, prev_sp); | |
5f1c39ef | 529 | target_store_registers (-1); |
41abdfbd | 530 | flush_cached_frames (); |
41abdfbd JG |
531 | } |
532 | ||
41abdfbd JG |
533 | /* fixup the call sequence of a dummy function, with the real function address. |
534 | its argumets will be passed by gdb. */ | |
535 | ||
ecf4059f | 536 | void |
41abdfbd JG |
537 | fix_call_dummy(dummyname, pc, fun, nargs, type) |
538 | char *dummyname; | |
ecf4059f JG |
539 | CORE_ADDR pc; |
540 | CORE_ADDR fun; | |
41abdfbd JG |
541 | int nargs; /* not used */ |
542 | int type; /* not used */ | |
41abdfbd JG |
543 | { |
544 | #define TOC_ADDR_OFFSET 20 | |
545 | #define TARGET_ADDR_OFFSET 28 | |
546 | ||
547 | int ii; | |
ecf4059f JG |
548 | CORE_ADDR target_addr; |
549 | CORE_ADDR tocvalue; | |
41abdfbd JG |
550 | |
551 | target_addr = fun; | |
552 | tocvalue = find_toc_address (target_addr); | |
553 | ||
554 | ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET); | |
555 | ii = (ii & 0xffff0000) | (tocvalue >> 16); | |
556 | *(int*)((char*)dummyname + TOC_ADDR_OFFSET) = ii; | |
557 | ||
558 | ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4); | |
559 | ii = (ii & 0xffff0000) | (tocvalue & 0x0000ffff); | |
560 | *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4) = ii; | |
561 | ||
562 | ii = *(int*)((char*)dummyname + TARGET_ADDR_OFFSET); | |
563 | ii = (ii & 0xffff0000) | (target_addr >> 16); | |
564 | *(int*)((char*)dummyname + TARGET_ADDR_OFFSET) = ii; | |
565 | ||
566 | ii = *(int*)((char*)dummyname + TARGET_ADDR_OFFSET+4); | |
567 | ii = (ii & 0xffff0000) | (target_addr & 0x0000ffff); | |
568 | *(int*)((char*)dummyname + TARGET_ADDR_OFFSET+4) = ii; | |
569 | } | |
570 | ||
571 | ||
41abdfbd | 572 | /* return information about a function frame. |
63641491 | 573 | in struct rs6000_frameinfo fdata: |
cdb1cc92 ILT |
574 | - frameless is TRUE, if function does not have a frame. |
575 | - nosavedpc is TRUE, if function does not save %pc value in its frame. | |
41abdfbd JG |
576 | - offset is the number of bytes used in the frame to save registers. |
577 | - saved_gpr is the number of the first saved gpr. | |
578 | - saved_fpr is the number of the first saved fpr. | |
6c6afbb9 PB |
579 | - alloca_reg is the number of the register used for alloca() handling. |
580 | Otherwise -1. | |
41abdfbd | 581 | */ |
ecf4059f | 582 | void |
6c6afbb9 | 583 | function_frame_info (pc, fdata) |
d6434f39 | 584 | CORE_ADDR pc; |
63641491 | 585 | struct rs6000_framedata *fdata; |
41abdfbd JG |
586 | { |
587 | unsigned int tmp; | |
588 | register unsigned int op; | |
9ed8604f | 589 | char buf[4]; |
41abdfbd | 590 | |
6c6afbb9 PB |
591 | fdata->offset = 0; |
592 | fdata->saved_gpr = fdata->saved_fpr = fdata->alloca_reg = -1; | |
cdb1cc92 | 593 | fdata->frameless = 1; |
41abdfbd | 594 | |
9ed8604f PS |
595 | /* Do not error out if we can't access the instructions. */ |
596 | if (target_read_memory (pc, buf, 4)) | |
597 | return; | |
598 | op = extract_unsigned_integer (buf, 4); | |
41abdfbd JG |
599 | if (op == 0x7c0802a6) { /* mflr r0 */ |
600 | pc += 4; | |
601 | op = read_memory_integer (pc, 4); | |
cdb1cc92 | 602 | fdata->nosavedpc = 0; |
6c6afbb9 | 603 | fdata->frameless = 0; |
41abdfbd | 604 | } |
cdb1cc92 ILT |
605 | else /* else, pc is not saved */ |
606 | fdata->nosavedpc = 1; | |
41abdfbd JG |
607 | |
608 | if ((op & 0xfc00003e) == 0x7c000026) { /* mfcr Rx */ | |
609 | pc += 4; | |
610 | op = read_memory_integer (pc, 4); | |
cdb1cc92 | 611 | fdata->frameless = 0; |
41abdfbd JG |
612 | } |
613 | ||
614 | if ((op & 0xfc000000) == 0x48000000) { /* bl foo, to save fprs??? */ | |
615 | pc += 4; | |
616 | op = read_memory_integer (pc, 4); | |
1eeba686 PB |
617 | /* At this point, make sure this is not a trampoline function |
618 | (a function that simply calls another functions, and nothing else). | |
619 | If the next is not a nop, this branch was part of the function | |
620 | prologue. */ | |
621 | ||
622 | if (op == 0x4def7b82 || /* crorc 15, 15, 15 */ | |
623 | op == 0x0) | |
624 | return; /* prologue is over */ | |
cdb1cc92 | 625 | fdata->frameless = 0; |
41abdfbd JG |
626 | } |
627 | ||
628 | if ((op & 0xfc1f0000) == 0xd8010000) { /* stfd Rx,NUM(r1) */ | |
629 | pc += 4; /* store floating register double */ | |
630 | op = read_memory_integer (pc, 4); | |
cdb1cc92 | 631 | fdata->frameless = 0; |
41abdfbd JG |
632 | } |
633 | ||
634 | if ((op & 0xfc1f0000) == 0xbc010000) { /* stm Rx, NUM(r1) */ | |
635 | int tmp2; | |
6c6afbb9 | 636 | fdata->saved_gpr = (op >> 21) & 0x1f; |
41abdfbd JG |
637 | tmp2 = op & 0xffff; |
638 | if (tmp2 > 0x7fff) | |
cdb1cc92 | 639 | tmp2 = (~0 &~ 0xffff) | tmp2; |
41abdfbd JG |
640 | |
641 | if (tmp2 < 0) { | |
642 | tmp2 = tmp2 * -1; | |
6c6afbb9 PB |
643 | fdata->saved_fpr = (tmp2 - ((32 - fdata->saved_gpr) * 4)) / 8; |
644 | if ( fdata->saved_fpr > 0) | |
645 | fdata->saved_fpr = 32 - fdata->saved_fpr; | |
41abdfbd | 646 | else |
6c6afbb9 | 647 | fdata->saved_fpr = -1; |
41abdfbd | 648 | } |
6c6afbb9 PB |
649 | fdata->offset = tmp2; |
650 | pc += 4; | |
651 | op = read_memory_integer (pc, 4); | |
cdb1cc92 | 652 | fdata->frameless = 0; |
41abdfbd | 653 | } |
6c6afbb9 PB |
654 | |
655 | while (((tmp = op >> 16) == 0x9001) || /* st r0, NUM(r1) */ | |
656 | (tmp == 0x9421) || /* stu r1, NUM(r1) */ | |
cdb1cc92 | 657 | (tmp == 0x93e1)) /* st r31, NUM(r1) */ |
6c6afbb9 | 658 | { |
cdb1cc92 ILT |
659 | int tmp2; |
660 | ||
6c6afbb9 PB |
661 | /* gcc takes a short cut and uses this instruction to save r31 only. */ |
662 | ||
cdb1cc92 | 663 | if (tmp == 0x93e1) { |
6c6afbb9 PB |
664 | if (fdata->offset) |
665 | /* fatal ("Unrecognized prolog."); */ | |
199b2450 | 666 | printf_unfiltered ("Unrecognized prolog!\n"); |
6c6afbb9 PB |
667 | |
668 | fdata->saved_gpr = 31; | |
cdb1cc92 ILT |
669 | tmp2 = op & 0xffff; |
670 | if (tmp2 > 0x7fff) { | |
671 | tmp2 = - ((~0 &~ 0xffff) | tmp2); | |
672 | fdata->saved_fpr = (tmp2 - ((32 - 31) * 4)) / 8; | |
673 | if ( fdata->saved_fpr > 0) | |
674 | fdata->saved_fpr = 32 - fdata->saved_fpr; | |
675 | else | |
676 | fdata->saved_fpr = -1; | |
677 | } | |
678 | fdata->offset = tmp2; | |
6c6afbb9 PB |
679 | } |
680 | pc += 4; | |
681 | op = read_memory_integer (pc, 4); | |
cdb1cc92 | 682 | fdata->frameless = 0; |
6c6afbb9 PB |
683 | } |
684 | ||
685 | while ((tmp = (op >> 22)) == 0x20f) { /* l r31, ... or */ | |
686 | pc += 4; /* l r30, ... */ | |
687 | op = read_memory_integer (pc, 4); | |
cdb1cc92 | 688 | fdata->frameless = 0; |
6c6afbb9 PB |
689 | } |
690 | ||
691 | /* store parameters into stack */ | |
692 | while( | |
693 | (op & 0xfc1f0000) == 0xd8010000 || /* stfd Rx,NUM(r1) */ | |
694 | (op & 0xfc1f0000) == 0x90010000 || /* st r?, NUM(r1) */ | |
695 | (op & 0xfc000000) == 0xfc000000 || /* frsp, fp?, .. */ | |
696 | (op & 0xd0000000) == 0xd0000000) /* stfs, fp?, .. */ | |
697 | { | |
698 | pc += 4; /* store fpr double */ | |
699 | op = read_memory_integer (pc, 4); | |
cdb1cc92 | 700 | fdata->frameless = 0; |
6c6afbb9 PB |
701 | } |
702 | ||
07aa9fdc PS |
703 | if (op == 0x603f0000 /* oril r31, r1, 0x0 */ |
704 | || op == 0x7c3f0b78) /* mr r31, r1 */ | |
705 | { | |
706 | fdata->alloca_reg = 31; | |
707 | fdata->frameless = 0; | |
708 | } | |
41abdfbd JG |
709 | } |
710 | ||
711 | ||
712 | /* Pass the arguments in either registers, or in the stack. In RS6000, the first | |
713 | eight words of the argument list (that might be less than eight parameters if | |
714 | some parameters occupy more than one word) are passed in r3..r11 registers. | |
715 | float and double parameters are passed in fpr's, in addition to that. Rest of | |
716 | the parameters if any are passed in user stack. There might be cases in which | |
717 | half of the parameter is copied into registers, the other half is pushed into | |
718 | stack. | |
719 | ||
720 | If the function is returning a structure, then the return address is passed | |
721 | in r3, then the first 7 words of the parametes can be passed in registers, | |
722 | starting from r4. */ | |
723 | ||
724 | CORE_ADDR | |
725 | push_arguments (nargs, args, sp, struct_return, struct_addr) | |
726 | int nargs; | |
17221e41 | 727 | value_ptr *args; |
41abdfbd JG |
728 | CORE_ADDR sp; |
729 | int struct_return; | |
730 | CORE_ADDR struct_addr; | |
731 | { | |
732 | int ii, len; | |
733 | int argno; /* current argument number */ | |
734 | int argbytes; /* current argument byte */ | |
735 | char tmp_buffer [50]; | |
17221e41 | 736 | value_ptr arg; |
41abdfbd JG |
737 | int f_argno = 0; /* current floating point argno */ |
738 | ||
739 | CORE_ADDR saved_sp, pc; | |
740 | ||
741 | if ( dummy_frame_count <= 0) | |
199b2450 | 742 | printf_unfiltered ("FATAL ERROR -push_arguments()! frame not found!!\n"); |
41abdfbd JG |
743 | |
744 | /* The first eight words of ther arguments are passed in registers. Copy | |
745 | them appropriately. | |
746 | ||
747 | If the function is returning a `struct', then the first word (which | |
748 | will be passed in r3) is used for struct return address. In that | |
749 | case we should advance one word and start from r4 register to copy | |
750 | parameters. */ | |
751 | ||
752 | ii = struct_return ? 1 : 0; | |
753 | ||
754 | for (argno=0, argbytes=0; argno < nargs && ii<8; ++ii) { | |
755 | ||
5222ca60 | 756 | arg = args[argno]; |
41abdfbd JG |
757 | len = TYPE_LENGTH (VALUE_TYPE (arg)); |
758 | ||
759 | if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FLT) { | |
760 | ||
761 | /* floating point arguments are passed in fpr's, as well as gpr's. | |
762 | There are 13 fpr's reserved for passing parameters. At this point | |
763 | there is no way we would run out of them. */ | |
764 | ||
765 | if (len > 8) | |
199b2450 | 766 | printf_unfiltered ( |
41abdfbd JG |
767 | "Fatal Error: a floating point parameter #%d with a size > 8 is found!\n", argno); |
768 | ||
ade40d31 RP |
769 | memcpy (®isters[REGISTER_BYTE(FP0_REGNUM + 1 + f_argno)], VALUE_CONTENTS (arg), |
770 | len); | |
41abdfbd JG |
771 | ++f_argno; |
772 | } | |
773 | ||
774 | if (len > 4) { | |
775 | ||
776 | /* Argument takes more than one register. */ | |
777 | while (argbytes < len) { | |
778 | ||
779 | *(int*)®isters[REGISTER_BYTE(ii+3)] = 0; | |
ade40d31 RP |
780 | memcpy (®isters[REGISTER_BYTE(ii+3)], |
781 | ((char*)VALUE_CONTENTS (arg))+argbytes, | |
41abdfbd JG |
782 | (len - argbytes) > 4 ? 4 : len - argbytes); |
783 | ++ii, argbytes += 4; | |
784 | ||
785 | if (ii >= 8) | |
786 | goto ran_out_of_registers_for_arguments; | |
787 | } | |
788 | argbytes = 0; | |
789 | --ii; | |
790 | } | |
791 | else { /* Argument can fit in one register. No problem. */ | |
792 | *(int*)®isters[REGISTER_BYTE(ii+3)] = 0; | |
ade40d31 | 793 | memcpy (®isters[REGISTER_BYTE(ii+3)], VALUE_CONTENTS (arg), len); |
41abdfbd JG |
794 | } |
795 | ++argno; | |
796 | } | |
797 | ||
798 | ran_out_of_registers_for_arguments: | |
799 | ||
800 | /* location for 8 parameters are always reserved. */ | |
801 | sp -= 4 * 8; | |
802 | ||
803 | /* another six words for back chain, TOC register, link register, etc. */ | |
804 | sp -= 24; | |
805 | ||
806 | /* if there are more arguments, allocate space for them in | |
807 | the stack, then push them starting from the ninth one. */ | |
808 | ||
809 | if ((argno < nargs) || argbytes) { | |
810 | int space = 0, jj; | |
17221e41 | 811 | value_ptr val; |
41abdfbd JG |
812 | |
813 | if (argbytes) { | |
814 | space += ((len - argbytes + 3) & -4); | |
815 | jj = argno + 1; | |
816 | } | |
817 | else | |
818 | jj = argno; | |
819 | ||
820 | for (; jj < nargs; ++jj) { | |
5222ca60 | 821 | val = args[jj]; |
41abdfbd JG |
822 | space += ((TYPE_LENGTH (VALUE_TYPE (val))) + 3) & -4; |
823 | } | |
824 | ||
825 | /* add location required for the rest of the parameters */ | |
826 | space = (space + 7) & -8; | |
827 | sp -= space; | |
828 | ||
829 | /* This is another instance we need to be concerned about securing our | |
830 | stack space. If we write anything underneath %sp (r1), we might conflict | |
831 | with the kernel who thinks he is free to use this area. So, update %sp | |
832 | first before doing anything else. */ | |
833 | ||
834 | write_register (SP_REGNUM, sp); | |
835 | ||
41abdfbd JG |
836 | /* if the last argument copied into the registers didn't fit there |
837 | completely, push the rest of it into stack. */ | |
838 | ||
839 | if (argbytes) { | |
840 | write_memory ( | |
841 | sp+24+(ii*4), ((char*)VALUE_CONTENTS (arg))+argbytes, len - argbytes); | |
842 | ++argno; | |
843 | ii += ((len - argbytes + 3) & -4) / 4; | |
844 | } | |
845 | ||
846 | /* push the rest of the arguments into stack. */ | |
847 | for (; argno < nargs; ++argno) { | |
848 | ||
5222ca60 | 849 | arg = args[argno]; |
41abdfbd JG |
850 | len = TYPE_LENGTH (VALUE_TYPE (arg)); |
851 | ||
852 | ||
853 | /* float types should be passed in fpr's, as well as in the stack. */ | |
854 | if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FLT && f_argno < 13) { | |
855 | ||
856 | if (len > 8) | |
199b2450 | 857 | printf_unfiltered ( |
41abdfbd JG |
858 | "Fatal Error: a floating point parameter #%d with a size > 8 is found!\n", argno); |
859 | ||
ade40d31 RP |
860 | memcpy (®isters[REGISTER_BYTE(FP0_REGNUM + 1 + f_argno)], VALUE_CONTENTS (arg), |
861 | len); | |
41abdfbd JG |
862 | ++f_argno; |
863 | } | |
864 | ||
359a097f | 865 | write_memory (sp+24+(ii*4), (char *) VALUE_CONTENTS (arg), len); |
41abdfbd JG |
866 | ii += ((len + 3) & -4) / 4; |
867 | } | |
868 | } | |
6c6afbb9 | 869 | else |
41abdfbd JG |
870 | /* Secure stack areas first, before doing anything else. */ |
871 | write_register (SP_REGNUM, sp); | |
872 | ||
41abdfbd JG |
873 | saved_sp = dummy_frame_addr [dummy_frame_count - 1]; |
874 | read_memory (saved_sp, tmp_buffer, 24); | |
875 | write_memory (sp, tmp_buffer, 24); | |
876 | ||
b112f2ae JK |
877 | /* set back chain properly */ |
878 | store_address (tmp_buffer, 4, saved_sp); | |
879 | write_memory (sp, tmp_buffer, 4); | |
41abdfbd | 880 | |
5f1c39ef | 881 | target_store_registers (-1); |
41abdfbd JG |
882 | return sp; |
883 | } | |
884 | ||
885 | /* a given return value in `regbuf' with a type `valtype', extract and copy its | |
886 | value into `valbuf' */ | |
887 | ||
ecf4059f | 888 | void |
41abdfbd JG |
889 | extract_return_value (valtype, regbuf, valbuf) |
890 | struct type *valtype; | |
891 | char regbuf[REGISTER_BYTES]; | |
892 | char *valbuf; | |
893 | { | |
894 | ||
895 | if (TYPE_CODE (valtype) == TYPE_CODE_FLT) { | |
896 | ||
897 | double dd; float ff; | |
898 | /* floats and doubles are returned in fpr1. fpr's have a size of 8 bytes. | |
899 | We need to truncate the return value into float size (4 byte) if | |
900 | necessary. */ | |
901 | ||
902 | if (TYPE_LENGTH (valtype) > 4) /* this is a double */ | |
ade40d31 | 903 | memcpy (valbuf, ®buf[REGISTER_BYTE (FP0_REGNUM + 1)], |
41abdfbd JG |
904 | TYPE_LENGTH (valtype)); |
905 | else { /* float */ | |
ade40d31 | 906 | memcpy (&dd, ®buf[REGISTER_BYTE (FP0_REGNUM + 1)], 8); |
41abdfbd | 907 | ff = (float)dd; |
ade40d31 | 908 | memcpy (valbuf, &ff, sizeof(float)); |
41abdfbd JG |
909 | } |
910 | } | |
911 | else | |
912 | /* return value is copied starting from r3. */ | |
ade40d31 | 913 | memcpy (valbuf, ®buf[REGISTER_BYTE (3)], TYPE_LENGTH (valtype)); |
41abdfbd JG |
914 | } |
915 | ||
916 | ||
ecf4059f JG |
917 | /* keep structure return address in this variable. |
918 | FIXME: This is a horrid kludge which should not be allowed to continue | |
919 | living. This only allows a single nested call to a structure-returning | |
920 | function. Come on, guys! -- gnu@cygnus.com, Aug 92 */ | |
41abdfbd JG |
921 | |
922 | CORE_ADDR rs6000_struct_return_address; | |
923 | ||
924 | ||
c2e4669f JG |
925 | /* Indirect function calls use a piece of trampoline code to do context |
926 | switching, i.e. to set the new TOC table. Skip such code if we are on | |
927 | its first instruction (as when we have single-stepped to here). | |
07aa9fdc PS |
928 | Also skip shared library trampoline code (which is different from |
929 | indirect function call trampolines). | |
c2e4669f JG |
930 | Result is desired PC to step until, or NULL if we are not in |
931 | trampoline code. */ | |
41abdfbd | 932 | |
ecf4059f | 933 | CORE_ADDR |
41abdfbd | 934 | skip_trampoline_code (pc) |
ecf4059f | 935 | CORE_ADDR pc; |
41abdfbd JG |
936 | { |
937 | register unsigned int ii, op; | |
07aa9fdc | 938 | CORE_ADDR solib_target_pc; |
41abdfbd JG |
939 | |
940 | static unsigned trampoline_code[] = { | |
941 | 0x800b0000, /* l r0,0x0(r11) */ | |
942 | 0x90410014, /* st r2,0x14(r1) */ | |
943 | 0x7c0903a6, /* mtctr r0 */ | |
944 | 0x804b0004, /* l r2,0x4(r11) */ | |
945 | 0x816b0008, /* l r11,0x8(r11) */ | |
946 | 0x4e800420, /* bctr */ | |
947 | 0x4e800020, /* br */ | |
948 | 0 | |
949 | }; | |
950 | ||
07aa9fdc PS |
951 | /* If pc is in a shared library trampoline, return its target. */ |
952 | solib_target_pc = find_solib_trampoline_target (pc); | |
953 | if (solib_target_pc) | |
954 | return solib_target_pc; | |
955 | ||
41abdfbd JG |
956 | for (ii=0; trampoline_code[ii]; ++ii) { |
957 | op = read_memory_integer (pc + (ii*4), 4); | |
958 | if (op != trampoline_code [ii]) | |
359a097f | 959 | return 0; |
41abdfbd JG |
960 | } |
961 | ii = read_register (11); /* r11 holds destination addr */ | |
962 | pc = read_memory_integer (ii, 4); /* (r11) value */ | |
963 | return pc; | |
964 | } | |
965 | ||
ecf4059f JG |
966 | |
967 | /* Determines whether the function FI has a frame on the stack or not. | |
cdb1cc92 ILT |
968 | Called from the FRAMELESS_FUNCTION_INVOCATION macro in tm.h with a |
969 | second argument of 0, and from the FRAME_SAVED_PC macro with a | |
970 | second argument of 1. */ | |
ecf4059f JG |
971 | |
972 | int | |
cdb1cc92 | 973 | frameless_function_invocation (fi, pcsaved) |
ecf4059f | 974 | struct frame_info *fi; |
cdb1cc92 | 975 | int pcsaved; |
ecf4059f JG |
976 | { |
977 | CORE_ADDR func_start; | |
63641491 | 978 | struct rs6000_framedata fdata; |
ecf4059f | 979 | |
b0e932ad JK |
980 | if (fi->next != NULL) |
981 | /* Don't even think about framelessness except on the innermost frame. */ | |
3f528883 JK |
982 | /* FIXME: Can also be frameless if fi->next->signal_handler_caller (if |
983 | a signal happens while executing in a frameless function). */ | |
b0e932ad JK |
984 | return 0; |
985 | ||
ecf4059f JG |
986 | func_start = get_pc_function_start (fi->pc) + FUNCTION_START_OFFSET; |
987 | ||
988 | /* If we failed to find the start of the function, it is a mistake | |
989 | to inspect the instructions. */ | |
990 | ||
991 | if (!func_start) | |
992 | return 0; | |
993 | ||
994 | function_frame_info (func_start, &fdata); | |
cdb1cc92 | 995 | return pcsaved ? fdata.nosavedpc : fdata.frameless; |
ecf4059f JG |
996 | } |
997 | ||
998 | ||
999 | /* If saved registers of frame FI are not known yet, read and cache them. | |
63641491 | 1000 | &FDATAP contains rs6000_framedata; TDATAP can be NULL, |
ecf4059f JG |
1001 | in which case the framedata are read. */ |
1002 | ||
1003 | static void | |
1004 | frame_get_cache_fsr (fi, fdatap) | |
1005 | struct frame_info *fi; | |
63641491 | 1006 | struct rs6000_framedata *fdatap; |
ecf4059f JG |
1007 | { |
1008 | int ii; | |
1009 | CORE_ADDR frame_addr; | |
63641491 | 1010 | struct rs6000_framedata work_fdata; |
ecf4059f JG |
1011 | |
1012 | if (fi->cache_fsr) | |
1013 | return; | |
1014 | ||
1015 | if (fdatap == NULL) { | |
1016 | fdatap = &work_fdata; | |
1017 | function_frame_info (get_pc_function_start (fi->pc), fdatap); | |
1018 | } | |
1019 | ||
1020 | fi->cache_fsr = (struct frame_saved_regs *) | |
1021 | obstack_alloc (&frame_cache_obstack, sizeof (struct frame_saved_regs)); | |
4ed97c9a | 1022 | memset (fi->cache_fsr, '\0', sizeof (struct frame_saved_regs)); |
ecf4059f JG |
1023 | |
1024 | if (fi->prev && fi->prev->frame) | |
1025 | frame_addr = fi->prev->frame; | |
1026 | else | |
1027 | frame_addr = read_memory_integer (fi->frame, 4); | |
1028 | ||
1029 | /* if != -1, fdatap->saved_fpr is the smallest number of saved_fpr. | |
1030 | All fpr's from saved_fpr to fp31 are saved right underneath caller | |
1031 | stack pointer, starting from fp31 first. */ | |
1032 | ||
1033 | if (fdatap->saved_fpr >= 0) { | |
1034 | for (ii=31; ii >= fdatap->saved_fpr; --ii) | |
1035 | fi->cache_fsr->regs [FP0_REGNUM + ii] = frame_addr - ((32 - ii) * 8); | |
1036 | frame_addr -= (32 - fdatap->saved_fpr) * 8; | |
1037 | } | |
1038 | ||
1039 | /* if != -1, fdatap->saved_gpr is the smallest number of saved_gpr. | |
1040 | All gpr's from saved_gpr to gpr31 are saved right under saved fprs, | |
1041 | starting from r31 first. */ | |
1042 | ||
1043 | if (fdatap->saved_gpr >= 0) | |
1044 | for (ii=31; ii >= fdatap->saved_gpr; --ii) | |
1045 | fi->cache_fsr->regs [ii] = frame_addr - ((32 - ii) * 4); | |
1046 | } | |
1047 | ||
1048 | /* Return the address of a frame. This is the inital %sp value when the frame | |
1049 | was first allocated. For functions calling alloca(), it might be saved in | |
1050 | an alloca register. */ | |
1051 | ||
1052 | CORE_ADDR | |
1053 | frame_initial_stack_address (fi) | |
1054 | struct frame_info *fi; | |
1055 | { | |
1056 | CORE_ADDR tmpaddr; | |
63641491 | 1057 | struct rs6000_framedata fdata; |
ecf4059f JG |
1058 | struct frame_info *callee_fi; |
1059 | ||
1060 | /* if the initial stack pointer (frame address) of this frame is known, | |
1061 | just return it. */ | |
1062 | ||
1063 | if (fi->initial_sp) | |
1064 | return fi->initial_sp; | |
1065 | ||
1066 | /* find out if this function is using an alloca register.. */ | |
1067 | ||
1068 | function_frame_info (get_pc_function_start (fi->pc), &fdata); | |
1069 | ||
1070 | /* if saved registers of this frame are not known yet, read and cache them. */ | |
1071 | ||
1072 | if (!fi->cache_fsr) | |
1073 | frame_get_cache_fsr (fi, &fdata); | |
1074 | ||
1075 | /* If no alloca register used, then fi->frame is the value of the %sp for | |
1076 | this frame, and it is good enough. */ | |
1077 | ||
1078 | if (fdata.alloca_reg < 0) { | |
1079 | fi->initial_sp = fi->frame; | |
1080 | return fi->initial_sp; | |
1081 | } | |
1082 | ||
1083 | /* This function has an alloca register. If this is the top-most frame | |
1084 | (with the lowest address), the value in alloca register is good. */ | |
1085 | ||
1086 | if (!fi->next) | |
1087 | return fi->initial_sp = read_register (fdata.alloca_reg); | |
1088 | ||
1089 | /* Otherwise, this is a caller frame. Callee has usually already saved | |
1090 | registers, but there are exceptions (such as when the callee | |
1091 | has no parameters). Find the address in which caller's alloca | |
1092 | register is saved. */ | |
1093 | ||
1094 | for (callee_fi = fi->next; callee_fi; callee_fi = callee_fi->next) { | |
1095 | ||
1096 | if (!callee_fi->cache_fsr) | |
cdb1cc92 | 1097 | frame_get_cache_fsr (callee_fi, NULL); |
ecf4059f JG |
1098 | |
1099 | /* this is the address in which alloca register is saved. */ | |
1100 | ||
1101 | tmpaddr = callee_fi->cache_fsr->regs [fdata.alloca_reg]; | |
1102 | if (tmpaddr) { | |
1103 | fi->initial_sp = read_memory_integer (tmpaddr, 4); | |
1104 | return fi->initial_sp; | |
1105 | } | |
1106 | ||
1107 | /* Go look into deeper levels of the frame chain to see if any one of | |
1108 | the callees has saved alloca register. */ | |
1109 | } | |
1110 | ||
1111 | /* If alloca register was not saved, by the callee (or any of its callees) | |
1112 | then the value in the register is still good. */ | |
1113 | ||
1114 | return fi->initial_sp = read_register (fdata.alloca_reg); | |
1115 | } | |
1116 | ||
669caa9c | 1117 | CORE_ADDR |
f3649227 JK |
1118 | rs6000_frame_chain (thisframe) |
1119 | struct frame_info *thisframe; | |
1120 | { | |
669caa9c | 1121 | CORE_ADDR fp; |
f3649227 JK |
1122 | if (inside_entry_file ((thisframe)->pc)) |
1123 | return 0; | |
cee86be3 | 1124 | if (thisframe->signal_handler_caller) |
9ed8604f | 1125 | fp = read_memory_integer (thisframe->frame + SIG_FRAME_FP_OFFSET, 4); |
cee86be3 JK |
1126 | else |
1127 | fp = read_memory_integer ((thisframe)->frame, 4); | |
1128 | ||
f3649227 JK |
1129 | return fp; |
1130 | } | |
ecf4059f JG |
1131 | \f |
1132 | /* Keep an array of load segment information and their TOC table addresses. | |
1133 | This info will be useful when calling a shared library function by hand. */ | |
1134 | ||
1135 | struct loadinfo { | |
1136 | CORE_ADDR textorg, dataorg; | |
1137 | unsigned long toc_offset; | |
1138 | }; | |
1139 | ||
1140 | #define LOADINFOLEN 10 | |
1141 | ||
ecf4059f JG |
1142 | static struct loadinfo *loadinfo = NULL; |
1143 | static int loadinfolen = 0; | |
1144 | static int loadinfotocindex = 0; | |
3c02636b | 1145 | static int loadinfotextindex = 0; |
ecf4059f JG |
1146 | |
1147 | ||
1148 | void | |
1149 | xcoff_init_loadinfo () | |
1150 | { | |
1151 | loadinfotocindex = 0; | |
1152 | loadinfotextindex = 0; | |
1153 | ||
1154 | if (loadinfolen == 0) { | |
1155 | loadinfo = (struct loadinfo *) | |
1156 | xmalloc (sizeof (struct loadinfo) * LOADINFOLEN); | |
1157 | loadinfolen = LOADINFOLEN; | |
1158 | } | |
1159 | } | |
1160 | ||
1161 | ||
1162 | /* FIXME -- this is never called! */ | |
1163 | void | |
1164 | free_loadinfo () | |
1165 | { | |
1166 | if (loadinfo) | |
1167 | free (loadinfo); | |
1168 | loadinfo = NULL; | |
1169 | loadinfolen = 0; | |
1170 | loadinfotocindex = 0; | |
1171 | loadinfotextindex = 0; | |
1172 | } | |
1173 | ||
1174 | /* this is called from xcoffread.c */ | |
1175 | ||
1176 | void | |
07dc1e42 MM |
1177 | xcoff_add_toc_to_loadinfo (tocoff) |
1178 | unsigned long tocoff; | |
ecf4059f JG |
1179 | { |
1180 | while (loadinfotocindex >= loadinfolen) { | |
1181 | loadinfolen += LOADINFOLEN; | |
1182 | loadinfo = (struct loadinfo *) | |
1183 | xrealloc (loadinfo, sizeof(struct loadinfo) * loadinfolen); | |
1184 | } | |
1185 | loadinfo [loadinfotocindex++].toc_offset = tocoff; | |
1186 | } | |
1187 | ||
2aefe6e4 | 1188 | void |
ecf4059f JG |
1189 | add_text_to_loadinfo (textaddr, dataaddr) |
1190 | CORE_ADDR textaddr; | |
1191 | CORE_ADDR dataaddr; | |
1192 | { | |
1193 | while (loadinfotextindex >= loadinfolen) { | |
1194 | loadinfolen += LOADINFOLEN; | |
1195 | loadinfo = (struct loadinfo *) | |
1196 | xrealloc (loadinfo, sizeof(struct loadinfo) * loadinfolen); | |
1197 | } | |
1198 | loadinfo [loadinfotextindex].textorg = textaddr; | |
1199 | loadinfo [loadinfotextindex].dataorg = dataaddr; | |
1200 | ++loadinfotextindex; | |
1201 | } | |
1202 | ||
1203 | ||
a367db89 | 1204 | /* Note that this assumes that the "textorg" and "dataorg" elements |
ecf4059f | 1205 | of a member of this array are correlated with the "toc_offset" |
a367db89 JK |
1206 | element of the same member. This is taken care of because the loops |
1207 | which assign the former (in xcoff_relocate_symtab or xcoff_relocate_core) | |
1208 | and the latter (in scan_xcoff_symtab, via vmap_symtab, in vmap_ldinfo | |
1209 | or xcoff_relocate_core) traverse the same objfiles in the same order. */ | |
ecf4059f JG |
1210 | |
1211 | static CORE_ADDR | |
1212 | find_toc_address (pc) | |
1213 | CORE_ADDR pc; | |
1214 | { | |
1215 | int ii, toc_entry, tocbase = 0; | |
1216 | ||
1217 | for (ii=0; ii < loadinfotextindex; ++ii) | |
1218 | if (pc > loadinfo[ii].textorg && loadinfo[ii].textorg > tocbase) { | |
1219 | toc_entry = ii; | |
1220 | tocbase = loadinfo[ii].textorg; | |
1221 | } | |
1222 | ||
1223 | return loadinfo[toc_entry].dataorg + loadinfo[toc_entry].toc_offset; | |
1224 | } | |
18b46e7c | 1225 | |
5c172b4b MM |
1226 | #ifdef GDB_TARGET_POWERPC |
1227 | int | |
1228 | gdb_print_insn_powerpc (memaddr, info) | |
1229 | bfd_vma memaddr; | |
1230 | disassemble_info *info; | |
1231 | { | |
1232 | if (TARGET_BYTE_ORDER == BIG_ENDIAN) | |
1233 | return print_insn_big_powerpc (memaddr, info); | |
1234 | else | |
1235 | return print_insn_little_powerpc (memaddr, info); | |
1236 | } | |
1237 | #endif | |
1238 | ||
18b46e7c SS |
1239 | void |
1240 | _initialize_rs6000_tdep () | |
1241 | { | |
1242 | /* FIXME, this should not be decided via ifdef. */ | |
1243 | #ifdef GDB_TARGET_POWERPC | |
5c172b4b | 1244 | tm_print_insn = gdb_print_insn_powerpc; |
18b46e7c SS |
1245 | #else |
1246 | tm_print_insn = print_insn_rs6000; | |
1247 | #endif | |
1248 | } |