1 /* Target-dependent code for GDB, the GNU debugger.
2 Copyright 1986, 1987, 1989, 1991, 1992, 1993, 1994, 1995
3 Free Software Foundation, Inc.
5 This file is part of GDB.
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.
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.
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. */
28 #include "xcoffsolib.h"
32 extern struct obstack frame_cache_obstack;
36 /* Nonzero if we just simulated a single step break. */
39 /* Breakpoint shadows for the single step instructions will be kept here. */
41 static struct sstep_breaks {
42 /* Address, or 0 if this is not in use. */
44 /* Shadow contents. */
48 /* Static function prototypes */
51 find_toc_address PARAMS ((CORE_ADDR pc));
54 branch_dest PARAMS ((int opcode, int instr, CORE_ADDR pc, CORE_ADDR safety));
57 frame_get_cache_fsr PARAMS ((struct frame_info *fi,
58 struct aix_framedata *fdatap));
61 * Calculate the destination of a branch/jump. Return -1 if not a branch.
64 branch_dest (opcode, instr, pc, safety)
76 absolute = (int) ((instr >> 1) & 1);
80 immediate = ((instr & ~3) << 6) >> 6; /* br unconditional */
84 dest = pc + immediate;
88 immediate = ((instr & ~3) << 16) >> 16; /* br conditional */
92 dest = pc + immediate;
96 ext_op = (instr>>1) & 0x3ff;
98 if (ext_op == 16) /* br conditional register */
99 dest = read_register (LR_REGNUM) & ~3;
101 else if (ext_op == 528) /* br cond to count reg */
103 dest = read_register (CTR_REGNUM) & ~3;
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;
116 return (dest < TEXT_SEGMENT_BASE) ? safety : dest;
121 /* AIX does not support PT_STEP. Simulate it. */
127 #define INSNLEN(OPCODE) 4
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;
140 insn = read_memory_integer (loc, 4);
142 breaks[0] = loc + INSNLEN(insn);
144 breaks[1] = branch_dest (opcode, insn, loc, breaks[0]);
146 /* Don't put two breakpoints on the same address. */
147 if (breaks[1] == breaks[0])
150 stepBreaks[1].address = 0;
152 for (ii=0; ii < 2; ++ii) {
154 /* ignore invalid breakpoint. */
155 if ( breaks[ii] == -1)
158 read_memory (breaks[ii], stepBreaks[ii].data, 4);
160 write_memory (breaks[ii], breakp, 4);
161 stepBreaks[ii].address = breaks[ii];
167 /* remove step breakpoints. */
168 for (ii=0; ii < 2; ++ii)
169 if (stepBreaks[ii].address != 0)
171 (stepBreaks[ii].address, stepBreaks[ii].data, 4);
175 errno = 0; /* FIXME, don't ignore errors! */
176 /* What errors? {read,write}_memory call error(). */
180 /* return pc value after skipping a function prologue. */
189 if (target_read_memory (pc, buf, 4))
190 return pc; /* Can't access it -- assume no prologue. */
191 op = extract_unsigned_integer (buf, 4);
193 /* Assume that subsequent fetches can fail with low probability. */
195 if (op == 0x7c0802a6) { /* mflr r0 */
197 op = read_memory_integer (pc, 4);
200 if ((op & 0xfc00003e) == 0x7c000026) { /* mfcr Rx */
202 op = read_memory_integer (pc, 4);
205 if ((op & 0xfc000000) == 0x48000000) { /* bl foo, to save fprs??? */
207 op = read_memory_integer (pc, 4);
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
214 if (op == 0x4def7b82 || /* crorc 15, 15, 15 */
216 return pc - 4; /* don't skip over this branch */
219 if ((op & 0xfc1f0000) == 0xd8010000) { /* stfd Rx,NUM(r1) */
220 pc += 4; /* store floating register double */
221 op = read_memory_integer (pc, 4);
224 if ((op & 0xfc1f0000) == 0xbc010000) { /* stm Rx, NUM(r1) */
226 op = read_memory_integer (pc, 4);
229 while ((op & 0xfc1f0000) == 0x90010000 && /* st rx,NUM(r1), rx >= r13 */
230 (op & 0x03e00000) >= 0x01a00000) {
232 op = read_memory_integer (pc, 4);
235 if (op == 0x90010008) { /* st r0,8(r1) */
237 op = read_memory_integer (pc, 4);
240 if (op == 0x91810004) { /* st r12,4(r1) */
242 op = read_memory_integer (pc, 4);
245 if ((op & 0xffff0000) == 0x94210000) { /* stu r1,NUM(r1) */
247 op = read_memory_integer (pc, 4);
250 while ((tmp = (op >> 22)) == 0x20f) { /* l r31, ... or */
251 pc += 4; /* l r30, ... */
252 op = read_memory_integer (pc, 4);
255 /* store parameters into stack */
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?, .. */
262 pc += 4; /* store fpr double */
263 op = read_memory_integer (pc, 4);
266 if (op == 0x603f0000 /* oril r31, r1, 0x0 */
267 || op == 0x7c3f0b78) { /* mr r31, r1 */
268 pc += 4; /* this happens if r31 is used as */
269 op = read_memory_integer (pc, 4); /* frame ptr. (gcc does that) */
272 while ((op >> 16) == (0x907f + tmp)) { /* st r3, NUM(r31) */
273 pc += 4; /* st r4, NUM(r31), ... */
274 op = read_memory_integer (pc, 4);
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 */
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. */
290 if ((op & 0xfc000001) == 0x48000001) { /* bl foo, an initializer function? */
291 op = read_memory_integer (pc+4, 4);
293 if (op == 0x4def7b82) { /* cror 0xf, 0xf, 0xf (nop) */
295 /* check and see if we are in main. If so, skip over this initializer
298 tmp = find_pc_misc_function (pc);
299 if (tmp >= 0 && STREQ (misc_function_vector [tmp].name, "main"))
309 /*************************************************************************
310 Support for creating pushind a dummy frame into the stack, and popping
312 *************************************************************************/
314 /* The total size of dummy frame is 436, which is;
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(). */
323 #define DUMMY_FRAME_SIZE 436
325 #define DUMMY_FRAME_ADDR_SIZE 10
327 /* Make sure you initialize these in somewhere, in case gdb gives up what it
328 was debugging and starts debugging something else. FIXMEibm */
330 static int dummy_frame_count = 0;
331 static int dummy_frame_size = 0;
332 static CORE_ADDR *dummy_frame_addr = 0;
334 extern int stop_stack_dummy;
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 */
344 /* Same thing, target byte order. */
349 /* Same thing, target byte order. */
354 target_fetch_registers (-1);
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));
362 dummy_frame_addr = (CORE_ADDR*)
363 xmalloc (sizeof(CORE_ADDR) * (dummy_frame_size));
366 sp = read_register(SP_REGNUM);
367 pc = read_register(PC_REGNUM);
368 store_address (pc_targ, 4, pc);
370 dummy_frame_addr [dummy_frame_count++] = sp;
372 /* Be careful! If the stack pointer is not decremented first, then kernel
373 thinks he is free to use the space underneath it. And kernel actually
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. */
378 write_register (SP_REGNUM, sp-DUMMY_FRAME_SIZE);
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! */
383 flush_cached_frames ();
385 /* save program counter in link register's space. */
386 write_memory (sp+8, pc_targ, 4);
388 /* save all floating point and general purpose registers here. */
391 for (ii = 0; ii < 32; ++ii)
392 write_memory (sp-8-(ii*8), ®isters[REGISTER_BYTE (31-ii+FP0_REGNUM)], 8);
395 for (ii=1; ii <=32; ++ii)
396 write_memory (sp-256-(ii*4), ®isters[REGISTER_BYTE (32-ii)], 4);
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 */
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);
406 /* Save sp or so called back chain right here. */
407 store_address (sp_targ, 4, sp);
408 write_memory (sp-DUMMY_FRAME_SIZE, sp_targ, 4);
409 sp -= DUMMY_FRAME_SIZE;
411 /* And finally, this is the back chain. */
412 write_memory (sp+8, pc_targ, 4);
416 /* Pop a dummy frame.
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.
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).
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
433 GDB process that keeps track of these dummy frames! -- gnu@cygnus.com Aug92
440 sp = dummy_frame_addr [--dummy_frame_count];
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);
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);
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);
456 read_memory (sp-(DUMMY_FRAME_SIZE-8),
457 ®isters [REGISTER_BYTE(PC_REGNUM)], 4);
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. */
463 *(int*)®isters [REGISTER_BYTE(FP_REGNUM)] = sp;
465 /* Now we can restore all registers. */
467 target_store_registers (-1);
469 flush_cached_frames ();
473 /* pop the innermost frame, go back to the caller. */
478 CORE_ADDR pc, lr, sp, prev_sp; /* %pc, %lr, %sp */
479 struct aix_framedata fdata;
480 struct frame_info *frame = get_current_frame ();
484 sp = FRAME_FP (frame);
486 if (stop_stack_dummy && dummy_frame_count) {
491 /* Make sure that all registers are valid. */
492 read_register_bytes (0, NULL, REGISTER_BYTES);
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. */
498 addr = get_pc_function_start (frame->pc) + FUNCTION_START_OFFSET;
499 function_frame_info (addr, &fdata);
504 prev_sp = read_memory_integer (sp, 4);
506 lr = read_register (LR_REGNUM);
508 lr = read_memory_integer (prev_sp+8, 4);
510 /* reset %pc value. */
511 write_register (PC_REGNUM, lr);
513 /* reset register values if any was saved earlier. */
514 addr = prev_sp - fdata.offset;
516 if (fdata.saved_gpr != -1)
517 for (ii = fdata.saved_gpr; ii <= 31; ++ii) {
518 read_memory (addr, ®isters [REGISTER_BYTE (ii)], 4);
522 if (fdata.saved_fpr != -1)
523 for (ii = fdata.saved_fpr; ii <= 31; ++ii) {
524 read_memory (addr, ®isters [REGISTER_BYTE (ii+FP0_REGNUM)], 8);
528 write_register (SP_REGNUM, prev_sp);
529 target_store_registers (-1);
530 flush_cached_frames ();
533 /* fixup the call sequence of a dummy function, with the real function address.
534 its argumets will be passed by gdb. */
537 fix_call_dummy(dummyname, pc, fun, nargs, type)
541 int nargs; /* not used */
542 int type; /* not used */
544 #define TOC_ADDR_OFFSET 20
545 #define TARGET_ADDR_OFFSET 28
548 CORE_ADDR target_addr;
552 tocvalue = find_toc_address (target_addr);
554 ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET);
555 ii = (ii & 0xffff0000) | (tocvalue >> 16);
556 *(int*)((char*)dummyname + TOC_ADDR_OFFSET) = ii;
558 ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4);
559 ii = (ii & 0xffff0000) | (tocvalue & 0x0000ffff);
560 *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4) = ii;
562 ii = *(int*)((char*)dummyname + TARGET_ADDR_OFFSET);
563 ii = (ii & 0xffff0000) | (target_addr >> 16);
564 *(int*)((char*)dummyname + TARGET_ADDR_OFFSET) = ii;
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;
572 /* return information about a function frame.
573 in struct aix_frameinfo fdata:
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.
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.
579 - alloca_reg is the number of the register used for alloca() handling.
583 function_frame_info (pc, fdata)
585 struct aix_framedata *fdata;
588 register unsigned int op;
592 fdata->saved_gpr = fdata->saved_fpr = fdata->alloca_reg = -1;
593 fdata->frameless = 1;
595 /* Do not error out if we can't access the instructions. */
596 if (target_read_memory (pc, buf, 4))
598 op = extract_unsigned_integer (buf, 4);
599 if (op == 0x7c0802a6) { /* mflr r0 */
601 op = read_memory_integer (pc, 4);
602 fdata->nosavedpc = 0;
603 fdata->frameless = 0;
605 else /* else, pc is not saved */
606 fdata->nosavedpc = 1;
608 if ((op & 0xfc00003e) == 0x7c000026) { /* mfcr Rx */
610 op = read_memory_integer (pc, 4);
611 fdata->frameless = 0;
614 if ((op & 0xfc000000) == 0x48000000) { /* bl foo, to save fprs??? */
616 op = read_memory_integer (pc, 4);
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
622 if (op == 0x4def7b82 || /* crorc 15, 15, 15 */
624 return; /* prologue is over */
625 fdata->frameless = 0;
628 if ((op & 0xfc1f0000) == 0xd8010000) { /* stfd Rx,NUM(r1) */
629 pc += 4; /* store floating register double */
630 op = read_memory_integer (pc, 4);
631 fdata->frameless = 0;
634 if ((op & 0xfc1f0000) == 0xbc010000) { /* stm Rx, NUM(r1) */
636 fdata->saved_gpr = (op >> 21) & 0x1f;
639 tmp2 = (~0 &~ 0xffff) | tmp2;
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;
647 fdata->saved_fpr = -1;
649 fdata->offset = tmp2;
651 op = read_memory_integer (pc, 4);
652 fdata->frameless = 0;
655 while (((tmp = op >> 16) == 0x9001) || /* st r0, NUM(r1) */
656 (tmp == 0x9421) || /* stu r1, NUM(r1) */
657 (tmp == 0x93e1)) /* st r31, NUM(r1) */
661 /* gcc takes a short cut and uses this instruction to save r31 only. */
665 /* fatal ("Unrecognized prolog."); */
666 printf_unfiltered ("Unrecognized prolog!\n");
668 fdata->saved_gpr = 31;
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;
676 fdata->saved_fpr = -1;
678 fdata->offset = tmp2;
681 op = read_memory_integer (pc, 4);
682 fdata->frameless = 0;
685 while ((tmp = (op >> 22)) == 0x20f) { /* l r31, ... or */
686 pc += 4; /* l r30, ... */
687 op = read_memory_integer (pc, 4);
688 fdata->frameless = 0;
691 /* store parameters into stack */
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?, .. */
698 pc += 4; /* store fpr double */
699 op = read_memory_integer (pc, 4);
700 fdata->frameless = 0;
703 if (op == 0x603f0000 /* oril r31, r1, 0x0 */
704 || op == 0x7c3f0b78) /* mr r31, r1 */
706 fdata->alloca_reg = 31;
707 fdata->frameless = 0;
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
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,
725 push_arguments (nargs, args, sp, struct_return, struct_addr)
730 CORE_ADDR struct_addr;
733 int argno; /* current argument number */
734 int argbytes; /* current argument byte */
735 char tmp_buffer [50];
737 int f_argno = 0; /* current floating point argno */
739 CORE_ADDR saved_sp, pc;
741 if ( dummy_frame_count <= 0)
742 printf_unfiltered ("FATAL ERROR -push_arguments()! frame not found!!\n");
744 /* The first eight words of ther arguments are passed in registers. Copy
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
752 ii = struct_return ? 1 : 0;
754 for (argno=0, argbytes=0; argno < nargs && ii<8; ++ii) {
757 len = TYPE_LENGTH (VALUE_TYPE (arg));
759 if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FLT) {
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. */
767 "Fatal Error: a floating point parameter #%d with a size > 8 is found!\n", argno);
769 memcpy (®isters[REGISTER_BYTE(FP0_REGNUM + 1 + f_argno)], VALUE_CONTENTS (arg),
776 /* Argument takes more than one register. */
777 while (argbytes < len) {
779 *(int*)®isters[REGISTER_BYTE(ii+3)] = 0;
780 memcpy (®isters[REGISTER_BYTE(ii+3)],
781 ((char*)VALUE_CONTENTS (arg))+argbytes,
782 (len - argbytes) > 4 ? 4 : len - argbytes);
786 goto ran_out_of_registers_for_arguments;
791 else { /* Argument can fit in one register. No problem. */
792 *(int*)®isters[REGISTER_BYTE(ii+3)] = 0;
793 memcpy (®isters[REGISTER_BYTE(ii+3)], VALUE_CONTENTS (arg), len);
798 ran_out_of_registers_for_arguments:
800 /* location for 8 parameters are always reserved. */
803 /* another six words for back chain, TOC register, link register, etc. */
806 /* if there are more arguments, allocate space for them in
807 the stack, then push them starting from the ninth one. */
809 if ((argno < nargs) || argbytes) {
814 space += ((len - argbytes + 3) & -4);
820 for (; jj < nargs; ++jj) {
822 space += ((TYPE_LENGTH (VALUE_TYPE (val))) + 3) & -4;
825 /* add location required for the rest of the parameters */
826 space = (space + 7) & -8;
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. */
834 write_register (SP_REGNUM, sp);
836 /* if the last argument copied into the registers didn't fit there
837 completely, push the rest of it into stack. */
841 sp+24+(ii*4), ((char*)VALUE_CONTENTS (arg))+argbytes, len - argbytes);
843 ii += ((len - argbytes + 3) & -4) / 4;
846 /* push the rest of the arguments into stack. */
847 for (; argno < nargs; ++argno) {
850 len = TYPE_LENGTH (VALUE_TYPE (arg));
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) {
858 "Fatal Error: a floating point parameter #%d with a size > 8 is found!\n", argno);
860 memcpy (®isters[REGISTER_BYTE(FP0_REGNUM + 1 + f_argno)], VALUE_CONTENTS (arg),
865 write_memory (sp+24+(ii*4), (char *) VALUE_CONTENTS (arg), len);
866 ii += ((len + 3) & -4) / 4;
870 /* Secure stack areas first, before doing anything else. */
871 write_register (SP_REGNUM, sp);
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);
877 /* set back chain properly */
878 store_address (tmp_buffer, 4, saved_sp);
879 write_memory (sp, tmp_buffer, 4);
881 target_store_registers (-1);
885 /* a given return value in `regbuf' with a type `valtype', extract and copy its
886 value into `valbuf' */
889 extract_return_value (valtype, regbuf, valbuf)
890 struct type *valtype;
891 char regbuf[REGISTER_BYTES];
895 if (TYPE_CODE (valtype) == TYPE_CODE_FLT) {
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
902 if (TYPE_LENGTH (valtype) > 4) /* this is a double */
903 memcpy (valbuf, ®buf[REGISTER_BYTE (FP0_REGNUM + 1)],
904 TYPE_LENGTH (valtype));
906 memcpy (&dd, ®buf[REGISTER_BYTE (FP0_REGNUM + 1)], 8);
908 memcpy (valbuf, &ff, sizeof(float));
912 /* return value is copied starting from r3. */
913 memcpy (valbuf, ®buf[REGISTER_BYTE (3)], TYPE_LENGTH (valtype));
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 */
922 CORE_ADDR rs6000_struct_return_address;
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).
928 Also skip shared library trampoline code (which is different from
929 indirect function call trampolines).
930 Result is desired PC to step until, or NULL if we are not in
934 skip_trampoline_code (pc)
937 register unsigned int ii, op;
938 CORE_ADDR solib_target_pc;
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 */
951 /* If pc is in a shared library trampoline, return its target. */
952 solib_target_pc = find_solib_trampoline_target (pc);
954 return solib_target_pc;
956 for (ii=0; trampoline_code[ii]; ++ii) {
957 op = read_memory_integer (pc + (ii*4), 4);
958 if (op != trampoline_code [ii])
961 ii = read_register (11); /* r11 holds destination addr */
962 pc = read_memory_integer (ii, 4); /* (r11) value */
967 /* Determines whether the function FI has a frame on the stack or not.
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. */
973 frameless_function_invocation (fi, pcsaved)
974 struct frame_info *fi;
977 CORE_ADDR func_start;
978 struct aix_framedata fdata;
980 if (fi->next != NULL)
981 /* Don't even think about framelessness except on the innermost frame. */
982 /* FIXME: Can also be frameless if fi->next->signal_handler_caller (if
983 a signal happens while executing in a frameless function). */
986 func_start = get_pc_function_start (fi->pc) + FUNCTION_START_OFFSET;
988 /* If we failed to find the start of the function, it is a mistake
989 to inspect the instructions. */
994 function_frame_info (func_start, &fdata);
995 return pcsaved ? fdata.nosavedpc : fdata.frameless;
999 /* If saved registers of frame FI are not known yet, read and cache them.
1000 &FDATAP contains aix_framedata; TDATAP can be NULL,
1001 in which case the framedata are read. */
1004 frame_get_cache_fsr (fi, fdatap)
1005 struct frame_info *fi;
1006 struct aix_framedata *fdatap;
1009 CORE_ADDR frame_addr;
1010 struct aix_framedata work_fdata;
1015 if (fdatap == NULL) {
1016 fdatap = &work_fdata;
1017 function_frame_info (get_pc_function_start (fi->pc), fdatap);
1020 fi->cache_fsr = (struct frame_saved_regs *)
1021 obstack_alloc (&frame_cache_obstack, sizeof (struct frame_saved_regs));
1022 memset (fi->cache_fsr, '\0', sizeof (struct frame_saved_regs));
1024 if (fi->prev && fi->prev->frame)
1025 frame_addr = fi->prev->frame;
1027 frame_addr = read_memory_integer (fi->frame, 4);
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. */
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;
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. */
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);
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. */
1053 frame_initial_stack_address (fi)
1054 struct frame_info *fi;
1057 struct aix_framedata fdata;
1058 struct frame_info *callee_fi;
1060 /* if the initial stack pointer (frame address) of this frame is known,
1064 return fi->initial_sp;
1066 /* find out if this function is using an alloca register.. */
1068 function_frame_info (get_pc_function_start (fi->pc), &fdata);
1070 /* if saved registers of this frame are not known yet, read and cache them. */
1073 frame_get_cache_fsr (fi, &fdata);
1075 /* If no alloca register used, then fi->frame is the value of the %sp for
1076 this frame, and it is good enough. */
1078 if (fdata.alloca_reg < 0) {
1079 fi->initial_sp = fi->frame;
1080 return fi->initial_sp;
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. */
1087 return fi->initial_sp = read_register (fdata.alloca_reg);
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. */
1094 for (callee_fi = fi->next; callee_fi; callee_fi = callee_fi->next) {
1096 if (!callee_fi->cache_fsr)
1097 frame_get_cache_fsr (callee_fi, NULL);
1099 /* this is the address in which alloca register is saved. */
1101 tmpaddr = callee_fi->cache_fsr->regs [fdata.alloca_reg];
1103 fi->initial_sp = read_memory_integer (tmpaddr, 4);
1104 return fi->initial_sp;
1107 /* Go look into deeper levels of the frame chain to see if any one of
1108 the callees has saved alloca register. */
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. */
1114 return fi->initial_sp = read_register (fdata.alloca_reg);
1118 rs6000_frame_chain (thisframe)
1119 struct frame_info *thisframe;
1122 if (inside_entry_file ((thisframe)->pc))
1124 if (thisframe->signal_handler_caller)
1125 fp = read_memory_integer (thisframe->frame + SIG_FRAME_FP_OFFSET, 4);
1127 fp = read_memory_integer ((thisframe)->frame, 4);
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. */
1136 CORE_ADDR textorg, dataorg;
1137 unsigned long toc_offset;
1140 #define LOADINFOLEN 10
1142 static struct loadinfo *loadinfo = NULL;
1143 static int loadinfolen = 0;
1144 static int loadinfotocindex = 0;
1145 static int loadinfotextindex = 0;
1149 xcoff_init_loadinfo ()
1151 loadinfotocindex = 0;
1152 loadinfotextindex = 0;
1154 if (loadinfolen == 0) {
1155 loadinfo = (struct loadinfo *)
1156 xmalloc (sizeof (struct loadinfo) * LOADINFOLEN);
1157 loadinfolen = LOADINFOLEN;
1162 /* FIXME -- this is never called! */
1170 loadinfotocindex = 0;
1171 loadinfotextindex = 0;
1174 /* this is called from xcoffread.c */
1177 xcoff_add_toc_to_loadinfo (tocoff)
1178 unsigned long tocoff;
1180 while (loadinfotocindex >= loadinfolen) {
1181 loadinfolen += LOADINFOLEN;
1182 loadinfo = (struct loadinfo *)
1183 xrealloc (loadinfo, sizeof(struct loadinfo) * loadinfolen);
1185 loadinfo [loadinfotocindex++].toc_offset = tocoff;
1189 add_text_to_loadinfo (textaddr, dataaddr)
1193 while (loadinfotextindex >= loadinfolen) {
1194 loadinfolen += LOADINFOLEN;
1195 loadinfo = (struct loadinfo *)
1196 xrealloc (loadinfo, sizeof(struct loadinfo) * loadinfolen);
1198 loadinfo [loadinfotextindex].textorg = textaddr;
1199 loadinfo [loadinfotextindex].dataorg = dataaddr;
1200 ++loadinfotextindex;
1204 /* Note that this assumes that the "textorg" and "dataorg" elements
1205 of a member of this array are correlated with the "toc_offset"
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. */
1212 find_toc_address (pc)
1215 int ii, toc_entry, tocbase = 0;
1217 for (ii=0; ii < loadinfotextindex; ++ii)
1218 if (pc > loadinfo[ii].textorg && loadinfo[ii].textorg > tocbase) {
1220 tocbase = loadinfo[ii].textorg;
1223 return loadinfo[toc_entry].dataorg + loadinfo[toc_entry].toc_offset;
1226 #ifdef GDB_TARGET_POWERPC
1228 gdb_print_insn_powerpc (memaddr, info)
1230 disassemble_info *info;
1232 if (TARGET_BYTE_ORDER == BIG_ENDIAN)
1233 return print_insn_big_powerpc (memaddr, info);
1235 return print_insn_little_powerpc (memaddr, info);
1240 _initialize_rs6000_tdep ()
1242 /* FIXME, this should not be decided via ifdef. */
1243 #ifdef GDB_TARGET_POWERPC
1244 tm_print_insn = gdb_print_insn_powerpc;
1246 tm_print_insn = print_insn_rs6000;