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>
33 #include <sys/ptrace.h>
44 /* Nonzero if we just simulated a single step break. */
48 /* Breakpoint shadows for the single step instructions will be kept here. */
50 static struct sstep_breaks
{
55 /* Static function prototypes */
58 add_text_to_loadinfo
PARAMS ((CORE_ADDR textaddr
, CORE_ADDR dataaddr
));
61 find_toc_address
PARAMS ((CORE_ADDR pc
));
64 branch_dest
PARAMS ((int opcode
, int instr
, CORE_ADDR pc
, CORE_ADDR safety
));
67 frame_get_cache_fsr
PARAMS ((struct frame_info
*fi
,
68 struct aix_framedata
*fdatap
));
71 * Calculate the destination of a branch/jump. Return -1 if not a branch.
74 branch_dest (opcode
, instr
, pc
, safety
)
86 absolute
= (int) ((instr
>> 1) & 1);
90 immediate
= ((instr
& ~3) << 6) >> 6; /* br unconditional */
93 if (opcode
!= 18) /* br conditional */
94 immediate
= ((instr
& ~3) << 16) >> 16;
98 dest
= pc
+ immediate
;
102 ext_op
= (instr
>>1) & 0x3ff;
104 if (ext_op
== 16) /* br conditional register */
105 dest
= read_register (LR_REGNUM
) & ~3;
107 else if (ext_op
== 528) /* br cond to count reg */
108 dest
= read_register (CTR_REGNUM
) & ~3;
115 return (dest
< TEXT_SEGMENT_BASE
) ? safety
: dest
;
120 /* AIX does not support PT_STEP. Simulate it. */
126 #define INSNLEN(OPCODE) 4
128 static char breakp
[] = BREAKPOINT
;
129 int ii
, insn
, ret
, loc
;
130 int breaks
[2], opcode
;
135 ret
= read_memory (loc
, &insn
, sizeof (int));
137 printf ("Error in single_step()!!\n");
139 breaks
[0] = loc
+ INSNLEN(insn
);
141 breaks
[1] = branch_dest (opcode
, insn
, loc
, breaks
[0]);
143 /* Don't put two breakpoints on the same address. */
144 if (breaks
[1] == breaks
[0])
147 stepBreaks
[1].address
= -1;
149 for (ii
=0; ii
< 2; ++ii
) {
151 /* ignore invalid breakpoint. */
152 if ( breaks
[ii
] == -1)
155 read_memory (breaks
[ii
], &(stepBreaks
[ii
].data
), sizeof(int));
157 ret
= write_memory (breaks
[ii
], breakp
, sizeof(int));
158 stepBreaks
[ii
].address
= breaks
[ii
];
162 ptrace (PT_CONTINUE
, inferior_pid
, (PTRACE_ARG3_TYPE
) 1, signal
, 0);
166 /* remove step breakpoints. */
167 for (ii
=0; ii
< 2; ++ii
)
168 if (stepBreaks
[ii
].address
!= -1)
170 (stepBreaks
[ii
].address
, &(stepBreaks
[ii
].data
), sizeof(int));
179 /* return pc value after skipping a function prologue. */
185 unsigned int op
; /* FIXME, assumes instruction size matches host int!!! */
187 if (target_read_memory (pc
, (char *)&op
, sizeof (op
)))
188 return pc
; /* Can't access it -- assume no prologue. */
189 SWAP_TARGET_AND_HOST (&op
, sizeof (op
));
191 /* Assume that subsequent fetches can fail with low probability. */
193 if (op
== 0x7c0802a6) { /* mflr r0 */
195 op
= read_memory_integer (pc
, 4);
198 if ((op
& 0xfc00003e) == 0x7c000026) { /* mfcr Rx */
200 op
= read_memory_integer (pc
, 4);
203 if ((op
& 0xfc000000) == 0x48000000) { /* bl foo, to save fprs??? */
205 op
= read_memory_integer (pc
, 4);
207 /* At this point, make sure this is not a trampoline function
208 (a function that simply calls another functions, and nothing else).
209 If the next is not a nop, this branch was part of the function
212 if (op
== 0x4def7b82 || /* crorc 15, 15, 15 */
214 return pc
- 4; /* don't skip over this branch */
217 if ((op
& 0xfc1f0000) == 0xbc010000) { /* stm Rx, NUM(r1) */
219 op
= read_memory_integer (pc
, 4);
222 while (((tmp
= op
>> 16) == 0x9001) || /* st r0, NUM(r1) */
223 (tmp
== 0x9421) || /* stu r1, NUM(r1) */
224 (op
== 0x93e1fffc)) /* st r31,-4(r1) */
227 op
= read_memory_integer (pc
, 4);
230 while ((tmp
= (op
>> 22)) == 0x20f) { /* l r31, ... or */
231 pc
+= 4; /* l r30, ... */
232 op
= read_memory_integer (pc
, 4);
235 /* store parameters into stack */
237 (op
& 0xfc1f0000) == 0xd8010000 || /* stfd Rx,NUM(r1) */
238 (op
& 0xfc1f0000) == 0x90010000 || /* st r?, NUM(r1) */
239 (op
& 0xfc000000) == 0xfc000000 || /* frsp, fp?, .. */
240 (op
& 0xd0000000) == 0xd0000000) /* stfs, fp?, .. */
242 pc
+= 4; /* store fpr double */
243 op
= read_memory_integer (pc
, 4);
246 if (op
== 0x603f0000) { /* oril r31, r1, 0x0 */
247 pc
+= 4; /* this happens if r31 is used as */
248 op
= read_memory_integer (pc
, 4); /* frame ptr. (gcc does that) */
251 while ((op
>> 16) == (0x907f + tmp
)) { /* st r3, NUM(r31) */
252 pc
+= 4; /* st r4, NUM(r31), ... */
253 op
= read_memory_integer (pc
, 4);
258 /* I have problems with skipping over __main() that I need to address
259 * sometime. Previously, I used to use misc_function_vector which
260 * didn't work as well as I wanted to be. -MGO */
262 /* If the first thing after skipping a prolog is a branch to a function,
263 this might be a call to an initializer in main(), introduced by gcc2.
264 We'd like to skip over it as well. Fortunately, xlc does some extra
265 work before calling a function right after a prologue, thus we can
266 single out such gcc2 behaviour. */
269 if ((op
& 0xfc000001) == 0x48000001) { /* bl foo, an initializer function? */
270 op
= read_memory_integer (pc
+4, 4);
272 if (op
== 0x4def7b82) { /* cror 0xf, 0xf, 0xf (nop) */
274 /* check and see if we are in main. If so, skip over this initializer
277 tmp
= find_pc_misc_function (pc
);
278 if (tmp
>= 0 && !strcmp (misc_function_vector
[tmp
].name
, "main"))
288 /*************************************************************************
289 Support for creating pushind a dummy frame into the stack, and popping
291 *************************************************************************/
293 /* The total size of dummy frame is 436, which is;
298 and 24 extra bytes for the callee's link area. The last 24 bytes
299 for the link area might not be necessary, since it will be taken
300 care of by push_arguments(). */
302 #define DUMMY_FRAME_SIZE 436
304 #define DUMMY_FRAME_ADDR_SIZE 10
306 /* Make sure you initialize these in somewhere, in case gdb gives up what it
307 was debugging and starts debugging something else. FIXMEibm */
309 static int dummy_frame_count
= 0;
310 static int dummy_frame_size
= 0;
311 static CORE_ADDR
*dummy_frame_addr
= 0;
313 extern int stop_stack_dummy
;
315 /* push a dummy frame into stack, save all register. Currently we are saving
316 only gpr's and fpr's, which is not good enough! FIXMEmgo */
321 int sp
, pc
; /* stack pointer and link register */
324 fetch_inferior_registers (-1);
326 if (dummy_frame_count
>= dummy_frame_size
) {
327 dummy_frame_size
+= DUMMY_FRAME_ADDR_SIZE
;
328 if (dummy_frame_addr
)
329 dummy_frame_addr
= (CORE_ADDR
*) xrealloc
330 (dummy_frame_addr
, sizeof(CORE_ADDR
) * (dummy_frame_size
));
332 dummy_frame_addr
= (CORE_ADDR
*)
333 xmalloc (sizeof(CORE_ADDR
) * (dummy_frame_size
));
336 sp
= read_register(SP_REGNUM
);
337 pc
= read_register(PC_REGNUM
);
339 dummy_frame_addr
[dummy_frame_count
++] = sp
;
341 /* Be careful! If the stack pointer is not decremented first, then kernel
342 thinks he is free to use the space underneath it. And kernel actually
343 uses that area for IPC purposes when executing ptrace(2) calls. So
344 before writing register values into the new frame, decrement and update
345 %sp first in order to secure your frame. */
347 write_register (SP_REGNUM
, sp
-DUMMY_FRAME_SIZE
);
349 /* gdb relies on the state of current_frame. We'd better update it,
350 otherwise things like do_registers_info() wouldn't work properly! */
352 flush_cached_frames ();
353 set_current_frame (create_new_frame (sp
-DUMMY_FRAME_SIZE
, pc
));
355 /* save program counter in link register's space. */
356 write_memory (sp
+8, &pc
, 4);
358 /* save all floating point and general purpose registers here. */
361 for (ii
= 0; ii
< 32; ++ii
)
362 write_memory (sp
-8-(ii
*8), ®isters
[REGISTER_BYTE (31-ii
+FP0_REGNUM
)], 8);
365 for (ii
=1; ii
<=32; ++ii
)
366 write_memory (sp
-256-(ii
*4), ®isters
[REGISTER_BYTE (32-ii
)], 4);
368 /* so far, 32*2 + 32 words = 384 bytes have been written.
369 7 extra registers in our register set: pc, ps, cnd, lr, cnt, xer, mq */
371 for (ii
=1; ii
<= (LAST_SP_REGNUM
-FIRST_SP_REGNUM
+1); ++ii
) {
372 write_memory (sp
-384-(ii
*4),
373 ®isters
[REGISTER_BYTE (FPLAST_REGNUM
+ ii
)], 4);
376 /* Save sp or so called back chain right here. */
377 write_memory (sp
-DUMMY_FRAME_SIZE
, &sp
, 4);
378 sp
-= DUMMY_FRAME_SIZE
;
380 /* And finally, this is the back chain. */
381 write_memory (sp
+8, &pc
, 4);
385 /* Pop a dummy frame.
387 In rs6000 when we push a dummy frame, we save all of the registers. This
388 is usually done before user calls a function explicitly.
390 After a dummy frame is pushed, some instructions are copied into stack,
391 and stack pointer is decremented even more. Since we don't have a frame
392 pointer to get back to the parent frame of the dummy, we start having
393 trouble poping it. Therefore, we keep a dummy frame stack, keeping
394 addresses of dummy frames as such. When poping happens and when we
395 detect that was a dummy frame, we pop it back to its parent by using
396 dummy frame stack (`dummy_frame_addr' array).
398 FIXME: This whole concept is broken. You should be able to detect
399 a dummy stack frame *on the user's stack itself*. When you do,
400 then you know the format of that stack frame -- including its
401 saved SP register! There should *not* be a separate stack in the
402 GDB process that keeps track of these dummy frames! -- gnu@cygnus.com Aug92 */
409 sp
= dummy_frame_addr
[--dummy_frame_count
];
411 /* restore all fpr's. */
412 for (ii
= 1; ii
<= 32; ++ii
)
413 read_memory (sp
-(ii
*8), ®isters
[REGISTER_BYTE (32-ii
+FP0_REGNUM
)], 8);
415 /* restore all gpr's */
416 for (ii
=1; ii
<= 32; ++ii
) {
417 read_memory (sp
-256-(ii
*4), ®isters
[REGISTER_BYTE (32-ii
)], 4);
420 /* restore the rest of the registers. */
421 for (ii
=1; ii
<=(LAST_SP_REGNUM
-FIRST_SP_REGNUM
+1); ++ii
)
422 read_memory (sp
-384-(ii
*4),
423 ®isters
[REGISTER_BYTE (FPLAST_REGNUM
+ ii
)], 4);
425 read_memory (sp
-(DUMMY_FRAME_SIZE
-8),
426 ®isters
[REGISTER_BYTE(PC_REGNUM
)], 4);
428 /* when a dummy frame was being pushed, we had to decrement %sp first, in
429 order to secure astack space. Thus, saved %sp (or %r1) value, is not the
430 one we should restore. Change it with the one we need. */
432 *(int*)®isters
[REGISTER_BYTE(FP_REGNUM
)] = sp
;
434 /* Now we can restore all registers. */
436 store_inferior_registers (-1);
438 flush_cached_frames ();
439 set_current_frame (create_new_frame (sp
, pc
));
443 /* pop the innermost frame, go back to the caller. */
448 int pc
, lr
, sp
, prev_sp
; /* %pc, %lr, %sp */
449 struct aix_framedata fdata
;
450 FRAME fr
= get_current_frame ();
456 if (stop_stack_dummy
&& dummy_frame_count
) {
461 /* figure out previous %pc value. If the function is frameless, it is
462 still in the link register, otherwise walk the frames and retrieve the
463 saved %pc value in the previous frame. */
465 addr
= get_pc_function_start (fr
->pc
) + FUNCTION_START_OFFSET
;
466 function_frame_info (addr
, &fdata
);
468 read_memory (sp
, &prev_sp
, 4);
470 lr
= read_register (LR_REGNUM
);
472 read_memory (prev_sp
+8, &lr
, 4);
474 /* reset %pc value. */
475 write_register (PC_REGNUM
, lr
);
477 /* reset register values if any was saved earlier. */
478 addr
= prev_sp
- fdata
.offset
;
480 if (fdata
.saved_gpr
!= -1)
481 for (ii
=fdata
.saved_gpr
; ii
<= 31; ++ii
) {
482 read_memory (addr
, ®isters
[REGISTER_BYTE (ii
)], 4);
483 addr
+= sizeof (int);
486 if (fdata
.saved_fpr
!= -1)
487 for (ii
=fdata
.saved_fpr
; ii
<= 31; ++ii
) {
488 read_memory (addr
, ®isters
[REGISTER_BYTE (ii
+FP0_REGNUM
)], 8);
492 write_register (SP_REGNUM
, prev_sp
);
493 store_inferior_registers (-1);
494 flush_cached_frames ();
495 set_current_frame (create_new_frame (prev_sp
, lr
));
499 /* fixup the call sequence of a dummy function, with the real function address.
500 its argumets will be passed by gdb. */
503 fix_call_dummy(dummyname
, pc
, fun
, nargs
, type
)
507 int nargs
; /* not used */
508 int type
; /* not used */
510 #define TOC_ADDR_OFFSET 20
511 #define TARGET_ADDR_OFFSET 28
514 CORE_ADDR target_addr
;
518 tocvalue
= find_toc_address (target_addr
);
520 ii
= *(int*)((char*)dummyname
+ TOC_ADDR_OFFSET
);
521 ii
= (ii
& 0xffff0000) | (tocvalue
>> 16);
522 *(int*)((char*)dummyname
+ TOC_ADDR_OFFSET
) = ii
;
524 ii
= *(int*)((char*)dummyname
+ TOC_ADDR_OFFSET
+4);
525 ii
= (ii
& 0xffff0000) | (tocvalue
& 0x0000ffff);
526 *(int*)((char*)dummyname
+ TOC_ADDR_OFFSET
+4) = ii
;
528 ii
= *(int*)((char*)dummyname
+ TARGET_ADDR_OFFSET
);
529 ii
= (ii
& 0xffff0000) | (target_addr
>> 16);
530 *(int*)((char*)dummyname
+ TARGET_ADDR_OFFSET
) = ii
;
532 ii
= *(int*)((char*)dummyname
+ TARGET_ADDR_OFFSET
+4);
533 ii
= (ii
& 0xffff0000) | (target_addr
& 0x0000ffff);
534 *(int*)((char*)dummyname
+ TARGET_ADDR_OFFSET
+4) = ii
;
538 /* return information about a function frame.
539 in struct aix_frameinfo fdata:
540 - frameless is TRUE, if function does not save %pc value in its frame.
541 - offset is the number of bytes used in the frame to save registers.
542 - saved_gpr is the number of the first saved gpr.
543 - saved_fpr is the number of the first saved fpr.
544 - alloca_reg is the number of the register used for alloca() handling.
548 function_frame_info (pc
, fdata
)
550 struct aix_framedata
*fdata
;
553 register unsigned int op
;
556 fdata
->saved_gpr
= fdata
->saved_fpr
= fdata
->alloca_reg
= -1;
558 op
= read_memory_integer (pc
, 4);
559 if (op
== 0x7c0802a6) { /* mflr r0 */
561 op
= read_memory_integer (pc
, 4);
562 fdata
->frameless
= 0;
564 else /* else, this is a frameless invocation */
565 fdata
->frameless
= 1;
568 if ((op
& 0xfc00003e) == 0x7c000026) { /* mfcr Rx */
570 op
= read_memory_integer (pc
, 4);
573 if ((op
& 0xfc000000) == 0x48000000) { /* bl foo, to save fprs??? */
575 op
= read_memory_integer (pc
, 4);
576 /* At this point, make sure this is not a trampoline function
577 (a function that simply calls another functions, and nothing else).
578 If the next is not a nop, this branch was part of the function
581 if (op
== 0x4def7b82 || /* crorc 15, 15, 15 */
583 return; /* prologue is over */
586 if ((op
& 0xfc1f0000) == 0xd8010000) { /* stfd Rx,NUM(r1) */
587 pc
+= 4; /* store floating register double */
588 op
= read_memory_integer (pc
, 4);
591 if ((op
& 0xfc1f0000) == 0xbc010000) { /* stm Rx, NUM(r1) */
593 fdata
->saved_gpr
= (op
>> 21) & 0x1f;
596 tmp2
= 0xffff0000 | tmp2
;
600 fdata
->saved_fpr
= (tmp2
- ((32 - fdata
->saved_gpr
) * 4)) / 8;
601 if ( fdata
->saved_fpr
> 0)
602 fdata
->saved_fpr
= 32 - fdata
->saved_fpr
;
604 fdata
->saved_fpr
= -1;
606 fdata
->offset
= tmp2
;
608 op
= read_memory_integer (pc
, 4);
611 while (((tmp
= op
>> 16) == 0x9001) || /* st r0, NUM(r1) */
612 (tmp
== 0x9421) || /* stu r1, NUM(r1) */
613 (op
== 0x93e1fffc)) /* st r31,-4(r1) */
615 /* gcc takes a short cut and uses this instruction to save r31 only. */
617 if (op
== 0x93e1fffc) {
619 /* fatal ("Unrecognized prolog."); */
620 printf ("Unrecognized prolog!\n");
622 fdata
->saved_gpr
= 31;
626 op
= read_memory_integer (pc
, 4);
629 while ((tmp
= (op
>> 22)) == 0x20f) { /* l r31, ... or */
630 pc
+= 4; /* l r30, ... */
631 op
= read_memory_integer (pc
, 4);
634 /* store parameters into stack */
636 (op
& 0xfc1f0000) == 0xd8010000 || /* stfd Rx,NUM(r1) */
637 (op
& 0xfc1f0000) == 0x90010000 || /* st r?, NUM(r1) */
638 (op
& 0xfc000000) == 0xfc000000 || /* frsp, fp?, .. */
639 (op
& 0xd0000000) == 0xd0000000) /* stfs, fp?, .. */
641 pc
+= 4; /* store fpr double */
642 op
= read_memory_integer (pc
, 4);
645 if (op
== 0x603f0000) /* oril r31, r1, 0x0 */
646 fdata
->alloca_reg
= 31;
650 /* Pass the arguments in either registers, or in the stack. In RS6000, the first
651 eight words of the argument list (that might be less than eight parameters if
652 some parameters occupy more than one word) are passed in r3..r11 registers.
653 float and double parameters are passed in fpr's, in addition to that. Rest of
654 the parameters if any are passed in user stack. There might be cases in which
655 half of the parameter is copied into registers, the other half is pushed into
658 If the function is returning a structure, then the return address is passed
659 in r3, then the first 7 words of the parametes can be passed in registers,
663 push_arguments (nargs
, args
, sp
, struct_return
, struct_addr
)
668 CORE_ADDR struct_addr
;
671 int argno
; /* current argument number */
672 int argbytes
; /* current argument byte */
673 char tmp_buffer
[50];
675 int f_argno
= 0; /* current floating point argno */
677 CORE_ADDR saved_sp
, pc
;
679 if ( dummy_frame_count
<= 0)
680 printf ("FATAL ERROR -push_arguments()! frame not found!!\n");
682 /* The first eight words of ther arguments are passed in registers. Copy
685 If the function is returning a `struct', then the first word (which
686 will be passed in r3) is used for struct return address. In that
687 case we should advance one word and start from r4 register to copy
690 ii
= struct_return
? 1 : 0;
692 for (argno
=0, argbytes
=0; argno
< nargs
&& ii
<8; ++ii
) {
694 arg
= value_arg_coerce (args
[argno
]);
695 len
= TYPE_LENGTH (VALUE_TYPE (arg
));
697 if (TYPE_CODE (VALUE_TYPE (arg
)) == TYPE_CODE_FLT
) {
699 /* floating point arguments are passed in fpr's, as well as gpr's.
700 There are 13 fpr's reserved for passing parameters. At this point
701 there is no way we would run out of them. */
705 "Fatal Error: a floating point parameter #%d with a size > 8 is found!\n", argno
);
707 bcopy (VALUE_CONTENTS (arg
),
708 ®isters
[REGISTER_BYTE(FP0_REGNUM
+ 1 + f_argno
)], len
);
714 /* Argument takes more than one register. */
715 while (argbytes
< len
) {
717 *(int*)®isters
[REGISTER_BYTE(ii
+3)] = 0;
718 bcopy ( ((char*)VALUE_CONTENTS (arg
))+argbytes
,
719 ®isters
[REGISTER_BYTE(ii
+3)],
720 (len
- argbytes
) > 4 ? 4 : len
- argbytes
);
724 goto ran_out_of_registers_for_arguments
;
729 else { /* Argument can fit in one register. No problem. */
730 *(int*)®isters
[REGISTER_BYTE(ii
+3)] = 0;
731 bcopy (VALUE_CONTENTS (arg
), ®isters
[REGISTER_BYTE(ii
+3)], len
);
736 ran_out_of_registers_for_arguments
:
738 /* location for 8 parameters are always reserved. */
741 /* another six words for back chain, TOC register, link register, etc. */
744 /* if there are more arguments, allocate space for them in
745 the stack, then push them starting from the ninth one. */
747 if ((argno
< nargs
) || argbytes
) {
752 space
+= ((len
- argbytes
+ 3) & -4);
758 for (; jj
< nargs
; ++jj
) {
759 val
= value_arg_coerce (args
[jj
]);
760 space
+= ((TYPE_LENGTH (VALUE_TYPE (val
))) + 3) & -4;
763 /* add location required for the rest of the parameters */
764 space
= (space
+ 7) & -8;
767 /* This is another instance we need to be concerned about securing our
768 stack space. If we write anything underneath %sp (r1), we might conflict
769 with the kernel who thinks he is free to use this area. So, update %sp
770 first before doing anything else. */
772 write_register (SP_REGNUM
, sp
);
774 /* if the last argument copied into the registers didn't fit there
775 completely, push the rest of it into stack. */
779 sp
+24+(ii
*4), ((char*)VALUE_CONTENTS (arg
))+argbytes
, len
- argbytes
);
781 ii
+= ((len
- argbytes
+ 3) & -4) / 4;
784 /* push the rest of the arguments into stack. */
785 for (; argno
< nargs
; ++argno
) {
787 arg
= value_arg_coerce (args
[argno
]);
788 len
= TYPE_LENGTH (VALUE_TYPE (arg
));
791 /* float types should be passed in fpr's, as well as in the stack. */
792 if (TYPE_CODE (VALUE_TYPE (arg
)) == TYPE_CODE_FLT
&& f_argno
< 13) {
796 "Fatal Error: a floating point parameter #%d with a size > 8 is found!\n", argno
);
798 bcopy (VALUE_CONTENTS (arg
),
799 ®isters
[REGISTER_BYTE(FP0_REGNUM
+ 1 + f_argno
)], len
);
803 write_memory (sp
+24+(ii
*4), VALUE_CONTENTS (arg
), len
);
804 ii
+= ((len
+ 3) & -4) / 4;
808 /* Secure stack areas first, before doing anything else. */
809 write_register (SP_REGNUM
, sp
);
811 saved_sp
= dummy_frame_addr
[dummy_frame_count
- 1];
812 read_memory (saved_sp
, tmp_buffer
, 24);
813 write_memory (sp
, tmp_buffer
, 24);
815 write_memory (sp
, &saved_sp
, 4); /* set back chain properly */
817 store_inferior_registers (-1);
821 /* a given return value in `regbuf' with a type `valtype', extract and copy its
822 value into `valbuf' */
825 extract_return_value (valtype
, regbuf
, valbuf
)
826 struct type
*valtype
;
827 char regbuf
[REGISTER_BYTES
];
831 if (TYPE_CODE (valtype
) == TYPE_CODE_FLT
) {
834 /* floats and doubles are returned in fpr1. fpr's have a size of 8 bytes.
835 We need to truncate the return value into float size (4 byte) if
838 if (TYPE_LENGTH (valtype
) > 4) /* this is a double */
839 bcopy (®buf
[REGISTER_BYTE (FP0_REGNUM
+ 1)], valbuf
,
840 TYPE_LENGTH (valtype
));
842 bcopy (®buf
[REGISTER_BYTE (FP0_REGNUM
+ 1)], &dd
, 8);
844 bcopy (&ff
, valbuf
, sizeof(float));
848 /* return value is copied starting from r3. */
849 bcopy (®buf
[REGISTER_BYTE (3)], valbuf
, TYPE_LENGTH (valtype
));
853 /* keep structure return address in this variable.
854 FIXME: This is a horrid kludge which should not be allowed to continue
855 living. This only allows a single nested call to a structure-returning
856 function. Come on, guys! -- gnu@cygnus.com, Aug 92 */
858 CORE_ADDR rs6000_struct_return_address
;
861 /* Throw away this debugging code. FIXMEmgo. */
867 for (ii
=0; ii
<40; ++ii
) {
870 val
= read_memory_integer (fram
+ ii
* 4, 4);
871 printf ("0x%08x\t", val
);
878 /* Indirect function calls use a piece of trampoline code to do context
879 switching, i.e. to set the new TOC table. Skip such code if we are on
880 its first instruction (as when we have single-stepped to here).
881 Result is desired PC to step until, or NULL if we are not in
885 skip_trampoline_code (pc
)
888 register unsigned int ii
, op
;
890 static unsigned trampoline_code
[] = {
891 0x800b0000, /* l r0,0x0(r11) */
892 0x90410014, /* st r2,0x14(r1) */
893 0x7c0903a6, /* mtctr r0 */
894 0x804b0004, /* l r2,0x4(r11) */
895 0x816b0008, /* l r11,0x8(r11) */
896 0x4e800420, /* bctr */
901 for (ii
=0; trampoline_code
[ii
]; ++ii
) {
902 op
= read_memory_integer (pc
+ (ii
*4), 4);
903 if (op
!= trampoline_code
[ii
])
906 ii
= read_register (11); /* r11 holds destination addr */
907 pc
= read_memory_integer (ii
, 4); /* (r11) value */
912 /* Determines whether the function FI has a frame on the stack or not.
913 Called from the FRAMELESS_FUNCTION_INVOCATION macro in tm.h. */
916 frameless_function_invocation (fi
)
917 struct frame_info
*fi
;
919 CORE_ADDR func_start
;
920 struct aix_framedata fdata
;
922 func_start
= get_pc_function_start (fi
->pc
) + FUNCTION_START_OFFSET
;
924 /* If we failed to find the start of the function, it is a mistake
925 to inspect the instructions. */
930 function_frame_info (func_start
, &fdata
);
931 return fdata
.frameless
;
935 /* If saved registers of frame FI are not known yet, read and cache them.
936 &FDATAP contains aix_framedata; TDATAP can be NULL,
937 in which case the framedata are read. */
940 frame_get_cache_fsr (fi
, fdatap
)
941 struct frame_info
*fi
;
942 struct aix_framedata
*fdatap
;
945 CORE_ADDR frame_addr
;
946 struct aix_framedata work_fdata
;
951 if (fdatap
== NULL
) {
952 fdatap
= &work_fdata
;
953 function_frame_info (get_pc_function_start (fi
->pc
), fdatap
);
956 fi
->cache_fsr
= (struct frame_saved_regs
*)
957 obstack_alloc (&frame_cache_obstack
, sizeof (struct frame_saved_regs
));
958 bzero (fi
->cache_fsr
, sizeof (struct frame_saved_regs
));
960 if (fi
->prev
&& fi
->prev
->frame
)
961 frame_addr
= fi
->prev
->frame
;
963 frame_addr
= read_memory_integer (fi
->frame
, 4);
965 /* if != -1, fdatap->saved_fpr is the smallest number of saved_fpr.
966 All fpr's from saved_fpr to fp31 are saved right underneath caller
967 stack pointer, starting from fp31 first. */
969 if (fdatap
->saved_fpr
>= 0) {
970 for (ii
=31; ii
>= fdatap
->saved_fpr
; --ii
)
971 fi
->cache_fsr
->regs
[FP0_REGNUM
+ ii
] = frame_addr
- ((32 - ii
) * 8);
972 frame_addr
-= (32 - fdatap
->saved_fpr
) * 8;
975 /* if != -1, fdatap->saved_gpr is the smallest number of saved_gpr.
976 All gpr's from saved_gpr to gpr31 are saved right under saved fprs,
977 starting from r31 first. */
979 if (fdatap
->saved_gpr
>= 0)
980 for (ii
=31; ii
>= fdatap
->saved_gpr
; --ii
)
981 fi
->cache_fsr
->regs
[ii
] = frame_addr
- ((32 - ii
) * 4);
984 /* Return the address of a frame. This is the inital %sp value when the frame
985 was first allocated. For functions calling alloca(), it might be saved in
986 an alloca register. */
989 frame_initial_stack_address (fi
)
990 struct frame_info
*fi
;
993 struct aix_framedata fdata
;
994 struct frame_info
*callee_fi
;
996 /* if the initial stack pointer (frame address) of this frame is known,
1000 return fi
->initial_sp
;
1002 /* find out if this function is using an alloca register.. */
1004 function_frame_info (get_pc_function_start (fi
->pc
), &fdata
);
1006 /* if saved registers of this frame are not known yet, read and cache them. */
1009 frame_get_cache_fsr (fi
, &fdata
);
1011 /* If no alloca register used, then fi->frame is the value of the %sp for
1012 this frame, and it is good enough. */
1014 if (fdata
.alloca_reg
< 0) {
1015 fi
->initial_sp
= fi
->frame
;
1016 return fi
->initial_sp
;
1019 /* This function has an alloca register. If this is the top-most frame
1020 (with the lowest address), the value in alloca register is good. */
1023 return fi
->initial_sp
= read_register (fdata
.alloca_reg
);
1025 /* Otherwise, this is a caller frame. Callee has usually already saved
1026 registers, but there are exceptions (such as when the callee
1027 has no parameters). Find the address in which caller's alloca
1028 register is saved. */
1030 for (callee_fi
= fi
->next
; callee_fi
; callee_fi
= callee_fi
->next
) {
1032 if (!callee_fi
->cache_fsr
)
1033 frame_get_cache_fsr (fi
, NULL
);
1035 /* this is the address in which alloca register is saved. */
1037 tmpaddr
= callee_fi
->cache_fsr
->regs
[fdata
.alloca_reg
];
1039 fi
->initial_sp
= read_memory_integer (tmpaddr
, 4);
1040 return fi
->initial_sp
;
1043 /* Go look into deeper levels of the frame chain to see if any one of
1044 the callees has saved alloca register. */
1047 /* If alloca register was not saved, by the callee (or any of its callees)
1048 then the value in the register is still good. */
1050 return fi
->initial_sp
= read_register (fdata
.alloca_reg
);
1053 /* xcoff_relocate_symtab - hook for symbol table relocation.
1054 also reads shared libraries.. */
1056 xcoff_relocate_symtab (pid
)
1059 #define MAX_LOAD_SEGS 64 /* maximum number of load segments */
1061 struct ld_info
*ldi
;
1064 ldi
= (void *) alloca(MAX_LOAD_SEGS
* sizeof (*ldi
));
1066 /* According to my humble theory, AIX has some timing problems and
1067 when the user stack grows, kernel doesn't update stack info in time
1068 and ptrace calls step on user stack. That is why we sleep here a little,
1069 and give kernel to update its internals. */
1074 ptrace(PT_LDINFO
, pid
, (PTRACE_ARG3_TYPE
) ldi
,
1075 MAX_LOAD_SEGS
* sizeof(*ldi
), ldi
);
1077 perror_with_name ("ptrace ldinfo");
1084 add_text_to_loadinfo (ldi
->ldinfo_textorg
, ldi
->ldinfo_dataorg
);
1085 } while (ldi
->ldinfo_next
1086 && (ldi
= (void *) (ldi
->ldinfo_next
+ (char *) ldi
)));
1089 /* Now that we've jumbled things around, re-sort them. */
1090 sort_minimal_symbols ();
1093 /* relocate the exec and core sections as well. */
1097 /* Keep an array of load segment information and their TOC table addresses.
1098 This info will be useful when calling a shared library function by hand. */
1101 CORE_ADDR textorg
, dataorg
;
1102 unsigned long toc_offset
;
1105 #define LOADINFOLEN 10
1107 /* FIXME Warning -- loadinfotextindex is used for a nefarious purpose by
1110 static struct loadinfo
*loadinfo
= NULL
;
1111 static int loadinfolen
= 0;
1112 static int loadinfotocindex
= 0;
1113 int loadinfotextindex
= 0;
1117 xcoff_init_loadinfo ()
1119 loadinfotocindex
= 0;
1120 loadinfotextindex
= 0;
1122 if (loadinfolen
== 0) {
1123 loadinfo
= (struct loadinfo
*)
1124 xmalloc (sizeof (struct loadinfo
) * LOADINFOLEN
);
1125 loadinfolen
= LOADINFOLEN
;
1130 /* FIXME -- this is never called! */
1138 loadinfotocindex
= 0;
1139 loadinfotextindex
= 0;
1142 /* this is called from xcoffread.c */
1145 xcoff_add_toc_to_loadinfo (unsigned long tocoff
)
1147 while (loadinfotocindex
>= loadinfolen
) {
1148 loadinfolen
+= LOADINFOLEN
;
1149 loadinfo
= (struct loadinfo
*)
1150 xrealloc (loadinfo
, sizeof(struct loadinfo
) * loadinfolen
);
1152 loadinfo
[loadinfotocindex
++].toc_offset
= tocoff
;
1157 add_text_to_loadinfo (textaddr
, dataaddr
)
1161 while (loadinfotextindex
>= loadinfolen
) {
1162 loadinfolen
+= LOADINFOLEN
;
1163 loadinfo
= (struct loadinfo
*)
1164 xrealloc (loadinfo
, sizeof(struct loadinfo
) * loadinfolen
);
1166 loadinfo
[loadinfotextindex
].textorg
= textaddr
;
1167 loadinfo
[loadinfotextindex
].dataorg
= dataaddr
;
1168 ++loadinfotextindex
;
1172 /* FIXME: This assumes that the "textorg" and "dataorg" elements
1173 of a member of this array are correlated with the "toc_offset"
1174 element of the same member. But they are sequentially assigned in wildly
1175 different places, and probably there is no correlation. FIXME! */
1178 find_toc_address (pc
)
1181 int ii
, toc_entry
, tocbase
= 0;
1183 for (ii
=0; ii
< loadinfotextindex
; ++ii
)
1184 if (pc
> loadinfo
[ii
].textorg
&& loadinfo
[ii
].textorg
> tocbase
) {
1186 tocbase
= loadinfo
[ii
].textorg
;
1189 return loadinfo
[toc_entry
].dataorg
+ loadinfo
[toc_entry
].toc_offset
;