1 /* Target-dependent code for GDB, the GNU debugger.
2 Copyright 1986, 1987, 1989, 1991, 1992 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
26 #include <sys/param.h>
30 #include <sys/ioctl.h>
40 extern struct obstack frame_cache_obstack
;
44 /* Nonzero if we just simulated a single step break. */
47 /* Breakpoint shadows for the single step instructions will be kept here. */
49 static struct sstep_breaks
{
54 /* Static function prototypes */
57 add_text_to_loadinfo
PARAMS ((CORE_ADDR textaddr
, CORE_ADDR dataaddr
));
60 find_toc_address
PARAMS ((CORE_ADDR pc
));
63 branch_dest
PARAMS ((int opcode
, int instr
, CORE_ADDR pc
, CORE_ADDR safety
));
66 frame_get_cache_fsr
PARAMS ((struct frame_info
*fi
,
67 struct aix_framedata
*fdatap
));
70 * Calculate the destination of a branch/jump. Return -1 if not a branch.
73 branch_dest (opcode
, instr
, pc
, safety
)
85 absolute
= (int) ((instr
>> 1) & 1);
89 immediate
= ((instr
& ~3) << 6) >> 6; /* br unconditional */
92 if (opcode
!= 18) /* br conditional */
93 immediate
= ((instr
& ~3) << 16) >> 16;
97 dest
= pc
+ immediate
;
101 ext_op
= (instr
>>1) & 0x3ff;
103 if (ext_op
== 16) /* br conditional register */
104 dest
= read_register (LR_REGNUM
) & ~3;
106 else if (ext_op
== 528) /* br cond to count reg */
107 dest
= read_register (CTR_REGNUM
) & ~3;
114 return (dest
< TEXT_SEGMENT_BASE
) ? safety
: dest
;
119 /* AIX does not support PT_STEP. Simulate it. */
125 #define INSNLEN(OPCODE) 4
127 static char breakp
[] = BREAKPOINT
;
128 int ii
, insn
, ret
, loc
;
129 int breaks
[2], opcode
;
134 ret
= read_memory (loc
, &insn
, sizeof (int));
136 printf ("Error in single_step()!!\n");
138 breaks
[0] = loc
+ INSNLEN(insn
);
140 breaks
[1] = branch_dest (opcode
, insn
, loc
, breaks
[0]);
142 /* Don't put two breakpoints on the same address. */
143 if (breaks
[1] == breaks
[0])
146 stepBreaks
[1].address
= -1;
148 for (ii
=0; ii
< 2; ++ii
) {
150 /* ignore invalid breakpoint. */
151 if ( breaks
[ii
] == -1)
154 read_memory (breaks
[ii
], &(stepBreaks
[ii
].data
), sizeof(int));
156 ret
= write_memory (breaks
[ii
], breakp
, sizeof(int));
157 stepBreaks
[ii
].address
= breaks
[ii
];
163 /* remove step breakpoints. */
164 for (ii
=0; ii
< 2; ++ii
)
165 if (stepBreaks
[ii
].address
!= -1)
167 (stepBreaks
[ii
].address
, &(stepBreaks
[ii
].data
), sizeof(int));
171 errno
= 0; /* FIXME, don't ignore errors! */
175 /* return pc value after skipping a function prologue. */
181 unsigned int op
; /* FIXME, assumes instruction size matches host int!!! */
183 if (target_read_memory (pc
, (char *)&op
, sizeof (op
)))
184 return pc
; /* Can't access it -- assume no prologue. */
185 SWAP_TARGET_AND_HOST (&op
, sizeof (op
));
187 /* Assume that subsequent fetches can fail with low probability. */
189 if (op
== 0x7c0802a6) { /* mflr r0 */
191 op
= read_memory_integer (pc
, 4);
194 if ((op
& 0xfc00003e) == 0x7c000026) { /* mfcr Rx */
196 op
= read_memory_integer (pc
, 4);
199 if ((op
& 0xfc000000) == 0x48000000) { /* bl foo, to save fprs??? */
201 op
= read_memory_integer (pc
, 4);
203 /* At this point, make sure this is not a trampoline function
204 (a function that simply calls another functions, and nothing else).
205 If the next is not a nop, this branch was part of the function
208 if (op
== 0x4def7b82 || /* crorc 15, 15, 15 */
210 return pc
- 4; /* don't skip over this branch */
213 if ((op
& 0xfc1f0000) == 0xd8010000) { /* stfd Rx,NUM(r1) */
214 pc
+= 4; /* store floating register double */
215 op
= read_memory_integer (pc
, 4);
218 if ((op
& 0xfc1f0000) == 0xbc010000) { /* stm Rx, NUM(r1) */
220 op
= read_memory_integer (pc
, 4);
223 while (((tmp
= op
>> 16) == 0x9001) || /* st r0, NUM(r1) */
224 (tmp
== 0x9421) || /* stu r1, NUM(r1) */
225 (tmp
== 0x93e1)) /* st r31,NUM(r1) */
228 op
= read_memory_integer (pc
, 4);
231 while ((tmp
= (op
>> 22)) == 0x20f) { /* l r31, ... or */
232 pc
+= 4; /* l r30, ... */
233 op
= read_memory_integer (pc
, 4);
236 /* store parameters into stack */
238 (op
& 0xfc1f0000) == 0xd8010000 || /* stfd Rx,NUM(r1) */
239 (op
& 0xfc1f0000) == 0x90010000 || /* st r?, NUM(r1) */
240 (op
& 0xfc000000) == 0xfc000000 || /* frsp, fp?, .. */
241 (op
& 0xd0000000) == 0xd0000000) /* stfs, fp?, .. */
243 pc
+= 4; /* store fpr double */
244 op
= read_memory_integer (pc
, 4);
247 if (op
== 0x603f0000) { /* oril r31, r1, 0x0 */
248 pc
+= 4; /* this happens if r31 is used as */
249 op
= read_memory_integer (pc
, 4); /* frame ptr. (gcc does that) */
252 while ((op
>> 16) == (0x907f + tmp
)) { /* st r3, NUM(r31) */
253 pc
+= 4; /* st r4, NUM(r31), ... */
254 op
= read_memory_integer (pc
, 4);
259 /* I have problems with skipping over __main() that I need to address
260 * sometime. Previously, I used to use misc_function_vector which
261 * didn't work as well as I wanted to be. -MGO */
263 /* If the first thing after skipping a prolog is a branch to a function,
264 this might be a call to an initializer in main(), introduced by gcc2.
265 We'd like to skip over it as well. Fortunately, xlc does some extra
266 work before calling a function right after a prologue, thus we can
267 single out such gcc2 behaviour. */
270 if ((op
& 0xfc000001) == 0x48000001) { /* bl foo, an initializer function? */
271 op
= read_memory_integer (pc
+4, 4);
273 if (op
== 0x4def7b82) { /* cror 0xf, 0xf, 0xf (nop) */
275 /* check and see if we are in main. If so, skip over this initializer
278 tmp
= find_pc_misc_function (pc
);
279 if (tmp
>= 0 && STREQ (misc_function_vector
[tmp
].name
, "main"))
289 /*************************************************************************
290 Support for creating pushind a dummy frame into the stack, and popping
292 *************************************************************************/
294 /* The total size of dummy frame is 436, which is;
299 and 24 extra bytes for the callee's link area. The last 24 bytes
300 for the link area might not be necessary, since it will be taken
301 care of by push_arguments(). */
303 #define DUMMY_FRAME_SIZE 436
305 #define DUMMY_FRAME_ADDR_SIZE 10
307 /* Make sure you initialize these in somewhere, in case gdb gives up what it
308 was debugging and starts debugging something else. FIXMEibm */
310 static int dummy_frame_count
= 0;
311 static int dummy_frame_size
= 0;
312 static CORE_ADDR
*dummy_frame_addr
= 0;
314 extern int stop_stack_dummy
;
316 /* push a dummy frame into stack, save all register. Currently we are saving
317 only gpr's and fpr's, which is not good enough! FIXMEmgo */
322 int sp
, pc
; /* stack pointer and link register */
325 target_fetch_registers (-1);
327 if (dummy_frame_count
>= dummy_frame_size
) {
328 dummy_frame_size
+= DUMMY_FRAME_ADDR_SIZE
;
329 if (dummy_frame_addr
)
330 dummy_frame_addr
= (CORE_ADDR
*) xrealloc
331 (dummy_frame_addr
, sizeof(CORE_ADDR
) * (dummy_frame_size
));
333 dummy_frame_addr
= (CORE_ADDR
*)
334 xmalloc (sizeof(CORE_ADDR
) * (dummy_frame_size
));
337 sp
= read_register(SP_REGNUM
);
338 pc
= read_register(PC_REGNUM
);
340 dummy_frame_addr
[dummy_frame_count
++] = sp
;
342 /* Be careful! If the stack pointer is not decremented first, then kernel
343 thinks he is free to use the space underneath it. And kernel actually
344 uses that area for IPC purposes when executing ptrace(2) calls. So
345 before writing register values into the new frame, decrement and update
346 %sp first in order to secure your frame. */
348 write_register (SP_REGNUM
, sp
-DUMMY_FRAME_SIZE
);
350 /* gdb relies on the state of current_frame. We'd better update it,
351 otherwise things like do_registers_info() wouldn't work properly! */
353 flush_cached_frames ();
354 set_current_frame (create_new_frame (sp
-DUMMY_FRAME_SIZE
, pc
));
356 /* save program counter in link register's space. */
357 write_memory (sp
+8, &pc
, 4);
359 /* save all floating point and general purpose registers here. */
362 for (ii
= 0; ii
< 32; ++ii
)
363 write_memory (sp
-8-(ii
*8), ®isters
[REGISTER_BYTE (31-ii
+FP0_REGNUM
)], 8);
366 for (ii
=1; ii
<=32; ++ii
)
367 write_memory (sp
-256-(ii
*4), ®isters
[REGISTER_BYTE (32-ii
)], 4);
369 /* so far, 32*2 + 32 words = 384 bytes have been written.
370 7 extra registers in our register set: pc, ps, cnd, lr, cnt, xer, mq */
372 for (ii
=1; ii
<= (LAST_SP_REGNUM
-FIRST_SP_REGNUM
+1); ++ii
) {
373 write_memory (sp
-384-(ii
*4),
374 ®isters
[REGISTER_BYTE (FPLAST_REGNUM
+ ii
)], 4);
377 /* Save sp or so called back chain right here. */
378 write_memory (sp
-DUMMY_FRAME_SIZE
, &sp
, 4);
379 sp
-= DUMMY_FRAME_SIZE
;
381 /* And finally, this is the back chain. */
382 write_memory (sp
+8, &pc
, 4);
386 /* Pop a dummy frame.
388 In rs6000 when we push a dummy frame, we save all of the registers. This
389 is usually done before user calls a function explicitly.
391 After a dummy frame is pushed, some instructions are copied into stack,
392 and stack pointer is decremented even more. Since we don't have a frame
393 pointer to get back to the parent frame of the dummy, we start having
394 trouble poping it. Therefore, we keep a dummy frame stack, keeping
395 addresses of dummy frames as such. When poping happens and when we
396 detect that was a dummy frame, we pop it back to its parent by using
397 dummy frame stack (`dummy_frame_addr' array).
399 FIXME: This whole concept is broken. You should be able to detect
400 a dummy stack frame *on the user's stack itself*. When you do,
401 then you know the format of that stack frame -- including its
402 saved SP register! There should *not* be a separate stack in the
403 GDB process that keeps track of these dummy frames! -- gnu@cygnus.com Aug92
410 sp
= dummy_frame_addr
[--dummy_frame_count
];
412 /* restore all fpr's. */
413 for (ii
= 1; ii
<= 32; ++ii
)
414 read_memory (sp
-(ii
*8), ®isters
[REGISTER_BYTE (32-ii
+FP0_REGNUM
)], 8);
416 /* restore all gpr's */
417 for (ii
=1; ii
<= 32; ++ii
) {
418 read_memory (sp
-256-(ii
*4), ®isters
[REGISTER_BYTE (32-ii
)], 4);
421 /* restore the rest of the registers. */
422 for (ii
=1; ii
<=(LAST_SP_REGNUM
-FIRST_SP_REGNUM
+1); ++ii
)
423 read_memory (sp
-384-(ii
*4),
424 ®isters
[REGISTER_BYTE (FPLAST_REGNUM
+ ii
)], 4);
426 read_memory (sp
-(DUMMY_FRAME_SIZE
-8),
427 ®isters
[REGISTER_BYTE(PC_REGNUM
)], 4);
429 /* when a dummy frame was being pushed, we had to decrement %sp first, in
430 order to secure astack space. Thus, saved %sp (or %r1) value, is not the
431 one we should restore. Change it with the one we need. */
433 *(int*)®isters
[REGISTER_BYTE(FP_REGNUM
)] = sp
;
435 /* Now we can restore all registers. */
437 target_store_registers (-1);
439 flush_cached_frames ();
440 set_current_frame (create_new_frame (sp
, pc
));
444 /* pop the innermost frame, go back to the caller. */
449 int pc
, lr
, sp
, prev_sp
; /* %pc, %lr, %sp */
450 struct aix_framedata fdata
;
451 FRAME fr
= get_current_frame ();
457 if (stop_stack_dummy
&& dummy_frame_count
) {
462 /* figure out previous %pc value. If the function is frameless, it is
463 still in the link register, otherwise walk the frames and retrieve the
464 saved %pc value in the previous frame. */
466 addr
= get_pc_function_start (fr
->pc
) + FUNCTION_START_OFFSET
;
467 function_frame_info (addr
, &fdata
);
469 read_memory (sp
, &prev_sp
, 4);
471 lr
= read_register (LR_REGNUM
);
473 read_memory (prev_sp
+8, &lr
, 4);
475 /* reset %pc value. */
476 write_register (PC_REGNUM
, lr
);
478 /* reset register values if any was saved earlier. */
479 addr
= prev_sp
- fdata
.offset
;
481 if (fdata
.saved_gpr
!= -1)
482 for (ii
=fdata
.saved_gpr
; ii
<= 31; ++ii
) {
483 read_memory (addr
, ®isters
[REGISTER_BYTE (ii
)], 4);
487 if (fdata
.saved_fpr
!= -1)
488 for (ii
=fdata
.saved_fpr
; ii
<= 31; ++ii
) {
489 read_memory (addr
, ®isters
[REGISTER_BYTE (ii
+FP0_REGNUM
)], 8);
493 write_register (SP_REGNUM
, prev_sp
);
494 target_store_registers (-1);
495 flush_cached_frames ();
496 set_current_frame (create_new_frame (prev_sp
, lr
));
500 /* fixup the call sequence of a dummy function, with the real function address.
501 its argumets will be passed by gdb. */
504 fix_call_dummy(dummyname
, pc
, fun
, nargs
, type
)
508 int nargs
; /* not used */
509 int type
; /* not used */
511 #define TOC_ADDR_OFFSET 20
512 #define TARGET_ADDR_OFFSET 28
515 CORE_ADDR target_addr
;
519 tocvalue
= find_toc_address (target_addr
);
521 ii
= *(int*)((char*)dummyname
+ TOC_ADDR_OFFSET
);
522 ii
= (ii
& 0xffff0000) | (tocvalue
>> 16);
523 *(int*)((char*)dummyname
+ TOC_ADDR_OFFSET
) = ii
;
525 ii
= *(int*)((char*)dummyname
+ TOC_ADDR_OFFSET
+4);
526 ii
= (ii
& 0xffff0000) | (tocvalue
& 0x0000ffff);
527 *(int*)((char*)dummyname
+ TOC_ADDR_OFFSET
+4) = ii
;
529 ii
= *(int*)((char*)dummyname
+ TARGET_ADDR_OFFSET
);
530 ii
= (ii
& 0xffff0000) | (target_addr
>> 16);
531 *(int*)((char*)dummyname
+ TARGET_ADDR_OFFSET
) = ii
;
533 ii
= *(int*)((char*)dummyname
+ TARGET_ADDR_OFFSET
+4);
534 ii
= (ii
& 0xffff0000) | (target_addr
& 0x0000ffff);
535 *(int*)((char*)dummyname
+ TARGET_ADDR_OFFSET
+4) = ii
;
539 /* return information about a function frame.
540 in struct aix_frameinfo fdata:
541 - frameless is TRUE, if function does not have a frame.
542 - nosavedpc is TRUE, if function does not save %pc value in its frame.
543 - offset is the number of bytes used in the frame to save registers.
544 - saved_gpr is the number of the first saved gpr.
545 - saved_fpr is the number of the first saved fpr.
546 - alloca_reg is the number of the register used for alloca() handling.
550 function_frame_info (pc
, fdata
)
552 struct aix_framedata
*fdata
;
555 register unsigned int op
;
558 fdata
->saved_gpr
= fdata
->saved_fpr
= fdata
->alloca_reg
= -1;
559 fdata
->frameless
= 1;
561 op
= read_memory_integer (pc
, 4);
562 if (op
== 0x7c0802a6) { /* mflr r0 */
564 op
= read_memory_integer (pc
, 4);
565 fdata
->nosavedpc
= 0;
566 fdata
->frameless
= 0;
568 else /* else, pc is not saved */
569 fdata
->nosavedpc
= 1;
571 if ((op
& 0xfc00003e) == 0x7c000026) { /* mfcr Rx */
573 op
= read_memory_integer (pc
, 4);
574 fdata
->frameless
= 0;
577 if ((op
& 0xfc000000) == 0x48000000) { /* bl foo, to save fprs??? */
579 op
= read_memory_integer (pc
, 4);
580 /* At this point, make sure this is not a trampoline function
581 (a function that simply calls another functions, and nothing else).
582 If the next is not a nop, this branch was part of the function
585 if (op
== 0x4def7b82 || /* crorc 15, 15, 15 */
587 return; /* prologue is over */
588 fdata
->frameless
= 0;
591 if ((op
& 0xfc1f0000) == 0xd8010000) { /* stfd Rx,NUM(r1) */
592 pc
+= 4; /* store floating register double */
593 op
= read_memory_integer (pc
, 4);
594 fdata
->frameless
= 0;
597 if ((op
& 0xfc1f0000) == 0xbc010000) { /* stm Rx, NUM(r1) */
599 fdata
->saved_gpr
= (op
>> 21) & 0x1f;
602 tmp2
= (~0 &~ 0xffff) | tmp2
;
606 fdata
->saved_fpr
= (tmp2
- ((32 - fdata
->saved_gpr
) * 4)) / 8;
607 if ( fdata
->saved_fpr
> 0)
608 fdata
->saved_fpr
= 32 - fdata
->saved_fpr
;
610 fdata
->saved_fpr
= -1;
612 fdata
->offset
= tmp2
;
614 op
= read_memory_integer (pc
, 4);
615 fdata
->frameless
= 0;
618 while (((tmp
= op
>> 16) == 0x9001) || /* st r0, NUM(r1) */
619 (tmp
== 0x9421) || /* stu r1, NUM(r1) */
620 (tmp
== 0x93e1)) /* st r31, NUM(r1) */
624 /* gcc takes a short cut and uses this instruction to save r31 only. */
628 /* fatal ("Unrecognized prolog."); */
629 printf ("Unrecognized prolog!\n");
631 fdata
->saved_gpr
= 31;
634 tmp2
= - ((~0 &~ 0xffff) | tmp2
);
635 fdata
->saved_fpr
= (tmp2
- ((32 - 31) * 4)) / 8;
636 if ( fdata
->saved_fpr
> 0)
637 fdata
->saved_fpr
= 32 - fdata
->saved_fpr
;
639 fdata
->saved_fpr
= -1;
641 fdata
->offset
= tmp2
;
644 op
= read_memory_integer (pc
, 4);
645 fdata
->frameless
= 0;
648 while ((tmp
= (op
>> 22)) == 0x20f) { /* l r31, ... or */
649 pc
+= 4; /* l r30, ... */
650 op
= read_memory_integer (pc
, 4);
651 fdata
->frameless
= 0;
654 /* store parameters into stack */
656 (op
& 0xfc1f0000) == 0xd8010000 || /* stfd Rx,NUM(r1) */
657 (op
& 0xfc1f0000) == 0x90010000 || /* st r?, NUM(r1) */
658 (op
& 0xfc000000) == 0xfc000000 || /* frsp, fp?, .. */
659 (op
& 0xd0000000) == 0xd0000000) /* stfs, fp?, .. */
661 pc
+= 4; /* store fpr double */
662 op
= read_memory_integer (pc
, 4);
663 fdata
->frameless
= 0;
666 if (op
== 0x603f0000) { /* oril r31, r1, 0x0 */
667 fdata
->alloca_reg
= 31;
668 fdata
->frameless
= 0;
673 /* Pass the arguments in either registers, or in the stack. In RS6000, the first
674 eight words of the argument list (that might be less than eight parameters if
675 some parameters occupy more than one word) are passed in r3..r11 registers.
676 float and double parameters are passed in fpr's, in addition to that. Rest of
677 the parameters if any are passed in user stack. There might be cases in which
678 half of the parameter is copied into registers, the other half is pushed into
681 If the function is returning a structure, then the return address is passed
682 in r3, then the first 7 words of the parametes can be passed in registers,
686 push_arguments (nargs
, args
, sp
, struct_return
, struct_addr
)
691 CORE_ADDR struct_addr
;
694 int argno
; /* current argument number */
695 int argbytes
; /* current argument byte */
696 char tmp_buffer
[50];
698 int f_argno
= 0; /* current floating point argno */
700 CORE_ADDR saved_sp
, pc
;
702 if ( dummy_frame_count
<= 0)
703 printf ("FATAL ERROR -push_arguments()! frame not found!!\n");
705 /* The first eight words of ther arguments are passed in registers. Copy
708 If the function is returning a `struct', then the first word (which
709 will be passed in r3) is used for struct return address. In that
710 case we should advance one word and start from r4 register to copy
713 ii
= struct_return
? 1 : 0;
715 for (argno
=0, argbytes
=0; argno
< nargs
&& ii
<8; ++ii
) {
717 arg
= value_arg_coerce (args
[argno
]);
718 len
= TYPE_LENGTH (VALUE_TYPE (arg
));
720 if (TYPE_CODE (VALUE_TYPE (arg
)) == TYPE_CODE_FLT
) {
722 /* floating point arguments are passed in fpr's, as well as gpr's.
723 There are 13 fpr's reserved for passing parameters. At this point
724 there is no way we would run out of them. */
728 "Fatal Error: a floating point parameter #%d with a size > 8 is found!\n", argno
);
730 bcopy (VALUE_CONTENTS (arg
),
731 ®isters
[REGISTER_BYTE(FP0_REGNUM
+ 1 + f_argno
)], len
);
737 /* Argument takes more than one register. */
738 while (argbytes
< len
) {
740 *(int*)®isters
[REGISTER_BYTE(ii
+3)] = 0;
741 bcopy ( ((char*)VALUE_CONTENTS (arg
))+argbytes
,
742 ®isters
[REGISTER_BYTE(ii
+3)],
743 (len
- argbytes
) > 4 ? 4 : len
- argbytes
);
747 goto ran_out_of_registers_for_arguments
;
752 else { /* Argument can fit in one register. No problem. */
753 *(int*)®isters
[REGISTER_BYTE(ii
+3)] = 0;
754 bcopy (VALUE_CONTENTS (arg
), ®isters
[REGISTER_BYTE(ii
+3)], len
);
759 ran_out_of_registers_for_arguments
:
761 /* location for 8 parameters are always reserved. */
764 /* another six words for back chain, TOC register, link register, etc. */
767 /* if there are more arguments, allocate space for them in
768 the stack, then push them starting from the ninth one. */
770 if ((argno
< nargs
) || argbytes
) {
775 space
+= ((len
- argbytes
+ 3) & -4);
781 for (; jj
< nargs
; ++jj
) {
782 val
= value_arg_coerce (args
[jj
]);
783 space
+= ((TYPE_LENGTH (VALUE_TYPE (val
))) + 3) & -4;
786 /* add location required for the rest of the parameters */
787 space
= (space
+ 7) & -8;
790 /* This is another instance we need to be concerned about securing our
791 stack space. If we write anything underneath %sp (r1), we might conflict
792 with the kernel who thinks he is free to use this area. So, update %sp
793 first before doing anything else. */
795 write_register (SP_REGNUM
, sp
);
797 /* if the last argument copied into the registers didn't fit there
798 completely, push the rest of it into stack. */
802 sp
+24+(ii
*4), ((char*)VALUE_CONTENTS (arg
))+argbytes
, len
- argbytes
);
804 ii
+= ((len
- argbytes
+ 3) & -4) / 4;
807 /* push the rest of the arguments into stack. */
808 for (; argno
< nargs
; ++argno
) {
810 arg
= value_arg_coerce (args
[argno
]);
811 len
= TYPE_LENGTH (VALUE_TYPE (arg
));
814 /* float types should be passed in fpr's, as well as in the stack. */
815 if (TYPE_CODE (VALUE_TYPE (arg
)) == TYPE_CODE_FLT
&& f_argno
< 13) {
819 "Fatal Error: a floating point parameter #%d with a size > 8 is found!\n", argno
);
821 bcopy (VALUE_CONTENTS (arg
),
822 ®isters
[REGISTER_BYTE(FP0_REGNUM
+ 1 + f_argno
)], len
);
826 write_memory (sp
+24+(ii
*4), VALUE_CONTENTS (arg
), len
);
827 ii
+= ((len
+ 3) & -4) / 4;
831 /* Secure stack areas first, before doing anything else. */
832 write_register (SP_REGNUM
, sp
);
834 saved_sp
= dummy_frame_addr
[dummy_frame_count
- 1];
835 read_memory (saved_sp
, tmp_buffer
, 24);
836 write_memory (sp
, tmp_buffer
, 24);
838 write_memory (sp
, &saved_sp
, 4); /* set back chain properly */
840 target_store_registers (-1);
844 /* a given return value in `regbuf' with a type `valtype', extract and copy its
845 value into `valbuf' */
848 extract_return_value (valtype
, regbuf
, valbuf
)
849 struct type
*valtype
;
850 char regbuf
[REGISTER_BYTES
];
854 if (TYPE_CODE (valtype
) == TYPE_CODE_FLT
) {
857 /* floats and doubles are returned in fpr1. fpr's have a size of 8 bytes.
858 We need to truncate the return value into float size (4 byte) if
861 if (TYPE_LENGTH (valtype
) > 4) /* this is a double */
862 bcopy (®buf
[REGISTER_BYTE (FP0_REGNUM
+ 1)], valbuf
,
863 TYPE_LENGTH (valtype
));
865 bcopy (®buf
[REGISTER_BYTE (FP0_REGNUM
+ 1)], &dd
, 8);
867 bcopy (&ff
, valbuf
, sizeof(float));
871 /* return value is copied starting from r3. */
872 bcopy (®buf
[REGISTER_BYTE (3)], valbuf
, TYPE_LENGTH (valtype
));
876 /* keep structure return address in this variable.
877 FIXME: This is a horrid kludge which should not be allowed to continue
878 living. This only allows a single nested call to a structure-returning
879 function. Come on, guys! -- gnu@cygnus.com, Aug 92 */
881 CORE_ADDR rs6000_struct_return_address
;
884 /* Throw away this debugging code. FIXMEmgo. */
890 for (ii
=0; ii
<40; ++ii
) {
893 val
= read_memory_integer (fram
+ ii
* 4, 4);
894 printf ("0x%08x\t", val
);
901 /* Indirect function calls use a piece of trampoline code to do context
902 switching, i.e. to set the new TOC table. Skip such code if we are on
903 its first instruction (as when we have single-stepped to here).
904 Result is desired PC to step until, or NULL if we are not in
908 skip_trampoline_code (pc
)
911 register unsigned int ii
, op
;
913 static unsigned trampoline_code
[] = {
914 0x800b0000, /* l r0,0x0(r11) */
915 0x90410014, /* st r2,0x14(r1) */
916 0x7c0903a6, /* mtctr r0 */
917 0x804b0004, /* l r2,0x4(r11) */
918 0x816b0008, /* l r11,0x8(r11) */
919 0x4e800420, /* bctr */
924 for (ii
=0; trampoline_code
[ii
]; ++ii
) {
925 op
= read_memory_integer (pc
+ (ii
*4), 4);
926 if (op
!= trampoline_code
[ii
])
929 ii
= read_register (11); /* r11 holds destination addr */
930 pc
= read_memory_integer (ii
, 4); /* (r11) value */
935 /* Determines whether the function FI has a frame on the stack or not.
936 Called from the FRAMELESS_FUNCTION_INVOCATION macro in tm.h with a
937 second argument of 0, and from the FRAME_SAVED_PC macro with a
938 second argument of 1. */
941 frameless_function_invocation (fi
, pcsaved
)
942 struct frame_info
*fi
;
945 CORE_ADDR func_start
;
946 struct aix_framedata fdata
;
948 func_start
= get_pc_function_start (fi
->pc
) + FUNCTION_START_OFFSET
;
950 /* If we failed to find the start of the function, it is a mistake
951 to inspect the instructions. */
956 function_frame_info (func_start
, &fdata
);
957 return pcsaved
? fdata
.nosavedpc
: fdata
.frameless
;
961 /* If saved registers of frame FI are not known yet, read and cache them.
962 &FDATAP contains aix_framedata; TDATAP can be NULL,
963 in which case the framedata are read. */
966 frame_get_cache_fsr (fi
, fdatap
)
967 struct frame_info
*fi
;
968 struct aix_framedata
*fdatap
;
971 CORE_ADDR frame_addr
;
972 struct aix_framedata work_fdata
;
977 if (fdatap
== NULL
) {
978 fdatap
= &work_fdata
;
979 function_frame_info (get_pc_function_start (fi
->pc
), fdatap
);
982 fi
->cache_fsr
= (struct frame_saved_regs
*)
983 obstack_alloc (&frame_cache_obstack
, sizeof (struct frame_saved_regs
));
984 bzero (fi
->cache_fsr
, sizeof (struct frame_saved_regs
));
986 if (fi
->prev
&& fi
->prev
->frame
)
987 frame_addr
= fi
->prev
->frame
;
989 frame_addr
= read_memory_integer (fi
->frame
, 4);
991 /* if != -1, fdatap->saved_fpr is the smallest number of saved_fpr.
992 All fpr's from saved_fpr to fp31 are saved right underneath caller
993 stack pointer, starting from fp31 first. */
995 if (fdatap
->saved_fpr
>= 0) {
996 for (ii
=31; ii
>= fdatap
->saved_fpr
; --ii
)
997 fi
->cache_fsr
->regs
[FP0_REGNUM
+ ii
] = frame_addr
- ((32 - ii
) * 8);
998 frame_addr
-= (32 - fdatap
->saved_fpr
) * 8;
1001 /* if != -1, fdatap->saved_gpr is the smallest number of saved_gpr.
1002 All gpr's from saved_gpr to gpr31 are saved right under saved fprs,
1003 starting from r31 first. */
1005 if (fdatap
->saved_gpr
>= 0)
1006 for (ii
=31; ii
>= fdatap
->saved_gpr
; --ii
)
1007 fi
->cache_fsr
->regs
[ii
] = frame_addr
- ((32 - ii
) * 4);
1010 /* Return the address of a frame. This is the inital %sp value when the frame
1011 was first allocated. For functions calling alloca(), it might be saved in
1012 an alloca register. */
1015 frame_initial_stack_address (fi
)
1016 struct frame_info
*fi
;
1019 struct aix_framedata fdata
;
1020 struct frame_info
*callee_fi
;
1022 /* if the initial stack pointer (frame address) of this frame is known,
1026 return fi
->initial_sp
;
1028 /* find out if this function is using an alloca register.. */
1030 function_frame_info (get_pc_function_start (fi
->pc
), &fdata
);
1032 /* if saved registers of this frame are not known yet, read and cache them. */
1035 frame_get_cache_fsr (fi
, &fdata
);
1037 /* If no alloca register used, then fi->frame is the value of the %sp for
1038 this frame, and it is good enough. */
1040 if (fdata
.alloca_reg
< 0) {
1041 fi
->initial_sp
= fi
->frame
;
1042 return fi
->initial_sp
;
1045 /* This function has an alloca register. If this is the top-most frame
1046 (with the lowest address), the value in alloca register is good. */
1049 return fi
->initial_sp
= read_register (fdata
.alloca_reg
);
1051 /* Otherwise, this is a caller frame. Callee has usually already saved
1052 registers, but there are exceptions (such as when the callee
1053 has no parameters). Find the address in which caller's alloca
1054 register is saved. */
1056 for (callee_fi
= fi
->next
; callee_fi
; callee_fi
= callee_fi
->next
) {
1058 if (!callee_fi
->cache_fsr
)
1059 frame_get_cache_fsr (callee_fi
, NULL
);
1061 /* this is the address in which alloca register is saved. */
1063 tmpaddr
= callee_fi
->cache_fsr
->regs
[fdata
.alloca_reg
];
1065 fi
->initial_sp
= read_memory_integer (tmpaddr
, 4);
1066 return fi
->initial_sp
;
1069 /* Go look into deeper levels of the frame chain to see if any one of
1070 the callees has saved alloca register. */
1073 /* If alloca register was not saved, by the callee (or any of its callees)
1074 then the value in the register is still good. */
1076 return fi
->initial_sp
= read_register (fdata
.alloca_reg
);
1079 /* xcoff_relocate_symtab - hook for symbol table relocation.
1080 also reads shared libraries.. */
1082 xcoff_relocate_symtab (pid
)
1085 #define MAX_LOAD_SEGS 64 /* maximum number of load segments */
1087 struct ld_info
*ldi
;
1090 ldi
= (void *) alloca(MAX_LOAD_SEGS
* sizeof (*ldi
));
1092 /* According to my humble theory, AIX has some timing problems and
1093 when the user stack grows, kernel doesn't update stack info in time
1094 and ptrace calls step on user stack. That is why we sleep here a little,
1095 and give kernel to update its internals. */
1100 ptrace(PT_LDINFO
, pid
, (PTRACE_ARG3_TYPE
) ldi
,
1101 MAX_LOAD_SEGS
* sizeof(*ldi
), ldi
);
1103 perror_with_name ("ptrace ldinfo");
1110 add_text_to_loadinfo (ldi
->ldinfo_textorg
, ldi
->ldinfo_dataorg
);
1111 } while (ldi
->ldinfo_next
1112 && (ldi
= (void *) (ldi
->ldinfo_next
+ (char *) ldi
)));
1115 /* Now that we've jumbled things around, re-sort them. */
1116 sort_minimal_symbols ();
1119 /* relocate the exec and core sections as well. */
1123 /* Keep an array of load segment information and their TOC table addresses.
1124 This info will be useful when calling a shared library function by hand. */
1127 CORE_ADDR textorg
, dataorg
;
1128 unsigned long toc_offset
;
1131 #define LOADINFOLEN 10
1133 /* FIXME Warning -- loadinfotextindex is used for a nefarious purpose by
1136 static struct loadinfo
*loadinfo
= NULL
;
1137 static int loadinfolen
= 0;
1138 static int loadinfotocindex
= 0;
1139 int loadinfotextindex
= 0;
1143 xcoff_init_loadinfo ()
1145 loadinfotocindex
= 0;
1146 loadinfotextindex
= 0;
1148 if (loadinfolen
== 0) {
1149 loadinfo
= (struct loadinfo
*)
1150 xmalloc (sizeof (struct loadinfo
) * LOADINFOLEN
);
1151 loadinfolen
= LOADINFOLEN
;
1156 /* FIXME -- this is never called! */
1164 loadinfotocindex
= 0;
1165 loadinfotextindex
= 0;
1168 /* this is called from xcoffread.c */
1171 xcoff_add_toc_to_loadinfo (unsigned long tocoff
)
1173 while (loadinfotocindex
>= loadinfolen
) {
1174 loadinfolen
+= LOADINFOLEN
;
1175 loadinfo
= (struct loadinfo
*)
1176 xrealloc (loadinfo
, sizeof(struct loadinfo
) * loadinfolen
);
1178 loadinfo
[loadinfotocindex
++].toc_offset
= tocoff
;
1183 add_text_to_loadinfo (textaddr
, dataaddr
)
1187 while (loadinfotextindex
>= loadinfolen
) {
1188 loadinfolen
+= LOADINFOLEN
;
1189 loadinfo
= (struct loadinfo
*)
1190 xrealloc (loadinfo
, sizeof(struct loadinfo
) * loadinfolen
);
1192 loadinfo
[loadinfotextindex
].textorg
= textaddr
;
1193 loadinfo
[loadinfotextindex
].dataorg
= dataaddr
;
1194 ++loadinfotextindex
;
1198 /* FIXME: This assumes that the "textorg" and "dataorg" elements
1199 of a member of this array are correlated with the "toc_offset"
1200 element of the same member. But they are sequentially assigned in wildly
1201 different places, and probably there is no correlation. FIXME! */
1204 find_toc_address (pc
)
1207 int ii
, toc_entry
, tocbase
= 0;
1209 for (ii
=0; ii
< loadinfotextindex
; ++ii
)
1210 if (pc
> loadinfo
[ii
].textorg
&& loadinfo
[ii
].textorg
> tocbase
) {
1212 tocbase
= loadinfo
[ii
].textorg
;
1215 return loadinfo
[toc_entry
].dataorg
+ loadinfo
[toc_entry
].toc_offset
;