1 /* Target-dependent code for the HP PA architecture, for GDB.
2 Copyright 1986, 1987, 1989, 1990, 1991, 1992, 1993, 1994
3 Free Software Foundation, Inc.
5 Contributed by the Center for Software Science at the
6 University of Utah (pa-gdb-bugs@cs.utah.edu).
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
29 /* For argument passing to the inferior */
33 #include <sys/types.h>
36 #include <sys/param.h>
40 #ifdef COFF_ENCAPSULATE
41 #include "a.out.encap.h"
45 #define N_SET_MAGIC(exec, val) ((exec).a_magic = (val))
48 /*#include <sys/user.h> After a.out.h */
59 static int restore_pc_queue
PARAMS ((struct frame_saved_regs
*));
61 static int hppa_alignof
PARAMS ((struct type
*));
63 CORE_ADDR frame_saved_pc
PARAMS ((struct frame_info
*));
65 static int prologue_inst_adjust_sp
PARAMS ((unsigned long));
67 static int is_branch
PARAMS ((unsigned long));
69 static int inst_saves_gr
PARAMS ((unsigned long));
71 static int inst_saves_fr
PARAMS ((unsigned long));
73 static int pc_in_interrupt_handler
PARAMS ((CORE_ADDR
));
75 static int pc_in_linker_stub
PARAMS ((CORE_ADDR
));
77 static int compare_unwind_entries
PARAMS ((const struct unwind_table_entry
*,
78 const struct unwind_table_entry
*));
80 static void read_unwind_info
PARAMS ((struct objfile
*));
82 static void internalize_unwinds
PARAMS ((struct objfile
*,
83 struct unwind_table_entry
*,
84 asection
*, unsigned int,
85 unsigned int, CORE_ADDR
));
88 /* Routines to extract various sized constants out of hppa
91 /* This assumes that no garbage lies outside of the lower bits of
95 sign_extend (val
, bits
)
98 return (int)(val
>> bits
- 1 ? (-1 << bits
) | val
: val
);
101 /* For many immediate values the sign bit is the low bit! */
104 low_sign_extend (val
, bits
)
107 return (int)((val
& 0x1 ? (-1 << (bits
- 1)) : 0) | val
>> 1);
109 /* extract the immediate field from a ld{bhw}s instruction */
112 get_field (val
, from
, to
)
113 unsigned val
, from
, to
;
115 val
= val
>> 31 - to
;
116 return val
& ((1 << 32 - from
) - 1);
120 set_field (val
, from
, to
, new_val
)
121 unsigned *val
, from
, to
;
123 unsigned mask
= ~((1 << (to
- from
+ 1)) << (31 - from
));
124 return *val
= *val
& mask
| (new_val
<< (31 - from
));
127 /* extract a 3-bit space register number from a be, ble, mtsp or mfsp */
132 return GET_FIELD (word
, 18, 18) << 2 | GET_FIELD (word
, 16, 17);
135 extract_5_load (word
)
138 return low_sign_extend (word
>> 16 & MASK_5
, 5);
141 /* extract the immediate field from a st{bhw}s instruction */
144 extract_5_store (word
)
147 return low_sign_extend (word
& MASK_5
, 5);
150 /* extract the immediate field from a break instruction */
153 extract_5r_store (word
)
156 return (word
& MASK_5
);
159 /* extract the immediate field from a {sr}sm instruction */
162 extract_5R_store (word
)
165 return (word
>> 16 & MASK_5
);
168 /* extract an 11 bit immediate field */
174 return low_sign_extend (word
& MASK_11
, 11);
177 /* extract a 14 bit immediate field */
183 return low_sign_extend (word
& MASK_14
, 14);
186 /* deposit a 14 bit constant in a word */
189 deposit_14 (opnd
, word
)
193 unsigned sign
= (opnd
< 0 ? 1 : 0);
195 return word
| ((unsigned)opnd
<< 1 & MASK_14
) | sign
;
198 /* extract a 21 bit constant */
208 val
= GET_FIELD (word
, 20, 20);
210 val
|= GET_FIELD (word
, 9, 19);
212 val
|= GET_FIELD (word
, 5, 6);
214 val
|= GET_FIELD (word
, 0, 4);
216 val
|= GET_FIELD (word
, 7, 8);
217 return sign_extend (val
, 21) << 11;
220 /* deposit a 21 bit constant in a word. Although 21 bit constants are
221 usually the top 21 bits of a 32 bit constant, we assume that only
222 the low 21 bits of opnd are relevant */
225 deposit_21 (opnd
, word
)
230 val
|= GET_FIELD (opnd
, 11 + 14, 11 + 18);
232 val
|= GET_FIELD (opnd
, 11 + 12, 11 + 13);
234 val
|= GET_FIELD (opnd
, 11 + 19, 11 + 20);
236 val
|= GET_FIELD (opnd
, 11 + 1, 11 + 11);
238 val
|= GET_FIELD (opnd
, 11 + 0, 11 + 0);
242 /* extract a 12 bit constant from branch instructions */
248 return sign_extend (GET_FIELD (word
, 19, 28) |
249 GET_FIELD (word
, 29, 29) << 10 |
250 (word
& 0x1) << 11, 12) << 2;
253 /* extract a 17 bit constant from branch instructions, returning the
254 19 bit signed value. */
260 return sign_extend (GET_FIELD (word
, 19, 28) |
261 GET_FIELD (word
, 29, 29) << 10 |
262 GET_FIELD (word
, 11, 15) << 11 |
263 (word
& 0x1) << 16, 17) << 2;
267 /* Compare the start address for two unwind entries returning 1 if
268 the first address is larger than the second, -1 if the second is
269 larger than the first, and zero if they are equal. */
272 compare_unwind_entries (a
, b
)
273 const struct unwind_table_entry
*a
;
274 const struct unwind_table_entry
*b
;
276 if (a
->region_start
> b
->region_start
)
278 else if (a
->region_start
< b
->region_start
)
285 internalize_unwinds (objfile
, table
, section
, entries
, size
, text_offset
)
286 struct objfile
*objfile
;
287 struct unwind_table_entry
*table
;
289 unsigned int entries
, size
;
290 CORE_ADDR text_offset
;
292 /* We will read the unwind entries into temporary memory, then
293 fill in the actual unwind table. */
298 char *buf
= alloca (size
);
300 bfd_get_section_contents (objfile
->obfd
, section
, buf
, 0, size
);
302 /* Now internalize the information being careful to handle host/target
304 for (i
= 0; i
< entries
; i
++)
306 table
[i
].region_start
= bfd_get_32 (objfile
->obfd
,
308 table
[i
].region_start
+= text_offset
;
310 table
[i
].region_end
= bfd_get_32 (objfile
->obfd
, (bfd_byte
*)buf
);
311 table
[i
].region_end
+= text_offset
;
313 tmp
= bfd_get_32 (objfile
->obfd
, (bfd_byte
*)buf
);
315 table
[i
].Cannot_unwind
= (tmp
>> 31) & 0x1;;
316 table
[i
].Millicode
= (tmp
>> 30) & 0x1;
317 table
[i
].Millicode_save_sr0
= (tmp
>> 29) & 0x1;
318 table
[i
].Region_description
= (tmp
>> 27) & 0x3;
319 table
[i
].reserved1
= (tmp
>> 26) & 0x1;
320 table
[i
].Entry_SR
= (tmp
>> 25) & 0x1;
321 table
[i
].Entry_FR
= (tmp
>> 21) & 0xf;
322 table
[i
].Entry_GR
= (tmp
>> 16) & 0x1f;
323 table
[i
].Args_stored
= (tmp
>> 15) & 0x1;
324 table
[i
].Variable_Frame
= (tmp
>> 14) & 0x1;
325 table
[i
].Separate_Package_Body
= (tmp
>> 13) & 0x1;
326 table
[i
].Frame_Extension_Millicode
= (tmp
>> 12 ) & 0x1;
327 table
[i
].Stack_Overflow_Check
= (tmp
>> 11) & 0x1;
328 table
[i
].Two_Instruction_SP_Increment
= (tmp
>> 10) & 0x1;
329 table
[i
].Ada_Region
= (tmp
>> 9) & 0x1;
330 table
[i
].reserved2
= (tmp
>> 5) & 0xf;
331 table
[i
].Save_SP
= (tmp
>> 4) & 0x1;
332 table
[i
].Save_RP
= (tmp
>> 3) & 0x1;
333 table
[i
].Save_MRP_in_frame
= (tmp
>> 2) & 0x1;
334 table
[i
].extn_ptr_defined
= (tmp
>> 1) & 0x1;
335 table
[i
].Cleanup_defined
= tmp
& 0x1;
336 tmp
= bfd_get_32 (objfile
->obfd
, (bfd_byte
*)buf
);
338 table
[i
].MPE_XL_interrupt_marker
= (tmp
>> 31) & 0x1;
339 table
[i
].HP_UX_interrupt_marker
= (tmp
>> 30) & 0x1;
340 table
[i
].Large_frame
= (tmp
>> 29) & 0x1;
341 table
[i
].reserved4
= (tmp
>> 27) & 0x3;
342 table
[i
].Total_frame_size
= tmp
& 0x7ffffff;
347 /* Read in the backtrace information stored in the `$UNWIND_START$' section of
348 the object file. This info is used mainly by find_unwind_entry() to find
349 out the stack frame size and frame pointer used by procedures. We put
350 everything on the psymbol obstack in the objfile so that it automatically
351 gets freed when the objfile is destroyed. */
354 read_unwind_info (objfile
)
355 struct objfile
*objfile
;
357 asection
*unwind_sec
, *elf_unwind_sec
, *stub_unwind_sec
;
358 unsigned unwind_size
, elf_unwind_size
, stub_unwind_size
, total_size
;
359 unsigned index
, unwind_entries
, elf_unwind_entries
;
360 unsigned stub_entries
, total_entries
;
361 CORE_ADDR text_offset
;
362 struct obj_unwind_info
*ui
;
364 text_offset
= ANOFFSET (objfile
->section_offsets
, 0);
365 ui
= obstack_alloc (&objfile
->psymbol_obstack
,
366 sizeof (struct obj_unwind_info
));
372 /* Get hooks to all unwind sections. Note there is no linker-stub unwind
373 section in ELF at the moment. */
374 unwind_sec
= bfd_get_section_by_name (objfile
->obfd
, "$UNWIND_START$");
375 elf_unwind_sec
= bfd_get_section_by_name (objfile
->obfd
, ".PARISC.unwind");
376 stub_unwind_sec
= bfd_get_section_by_name (objfile
->obfd
, "$UNWIND_END$");
378 /* Get sizes and unwind counts for all sections. */
381 unwind_size
= bfd_section_size (objfile
->obfd
, unwind_sec
);
382 unwind_entries
= unwind_size
/ UNWIND_ENTRY_SIZE
;
392 elf_unwind_size
= bfd_section_size (objfile
->obfd
, elf_unwind_sec
);
393 elf_unwind_entries
= elf_unwind_size
/ UNWIND_ENTRY_SIZE
;
398 elf_unwind_entries
= 0;
403 stub_unwind_size
= bfd_section_size (objfile
->obfd
, stub_unwind_sec
);
404 stub_entries
= stub_unwind_size
/ STUB_UNWIND_ENTRY_SIZE
;
408 stub_unwind_size
= 0;
412 /* Compute total number of unwind entries and their total size. */
413 total_entries
= unwind_entries
+ elf_unwind_entries
+ stub_entries
;
414 total_size
= total_entries
* sizeof (struct unwind_table_entry
);
416 /* Allocate memory for the unwind table. */
417 ui
->table
= obstack_alloc (&objfile
->psymbol_obstack
, total_size
);
418 ui
->last
= total_entries
- 1;
420 /* Internalize the standard unwind entries. */
422 internalize_unwinds (objfile
, &ui
->table
[index
], unwind_sec
,
423 unwind_entries
, unwind_size
, text_offset
);
424 index
+= unwind_entries
;
425 internalize_unwinds (objfile
, &ui
->table
[index
], elf_unwind_sec
,
426 elf_unwind_entries
, elf_unwind_size
, text_offset
);
427 index
+= elf_unwind_entries
;
429 /* Now internalize the stub unwind entries. */
430 if (stub_unwind_size
> 0)
433 char *buf
= alloca (stub_unwind_size
);
435 /* Read in the stub unwind entries. */
436 bfd_get_section_contents (objfile
->obfd
, stub_unwind_sec
, buf
,
437 0, stub_unwind_size
);
439 /* Now convert them into regular unwind entries. */
440 for (i
= 0; i
< stub_entries
; i
++, index
++)
442 /* Clear out the next unwind entry. */
443 memset (&ui
->table
[index
], 0, sizeof (struct unwind_table_entry
));
445 /* Convert offset & size into region_start and region_end.
446 Stuff away the stub type into "reserved" fields. */
447 ui
->table
[index
].region_start
= bfd_get_32 (objfile
->obfd
,
449 ui
->table
[index
].region_start
+= text_offset
;
451 ui
->table
[index
].stub_type
= bfd_get_8 (objfile
->obfd
,
454 ui
->table
[index
].region_end
455 = ui
->table
[index
].region_start
+ 4 *
456 (bfd_get_16 (objfile
->obfd
, (bfd_byte
*) buf
) - 1);
462 /* Unwind table needs to be kept sorted. */
463 qsort (ui
->table
, total_entries
, sizeof (struct unwind_table_entry
),
464 compare_unwind_entries
);
466 /* Keep a pointer to the unwind information. */
467 objfile
->obj_private
= (PTR
) ui
;
470 /* Lookup the unwind (stack backtrace) info for the given PC. We search all
471 of the objfiles seeking the unwind table entry for this PC. Each objfile
472 contains a sorted list of struct unwind_table_entry. Since we do a binary
473 search of the unwind tables, we depend upon them to be sorted. */
475 static struct unwind_table_entry
*
476 find_unwind_entry(pc
)
479 int first
, middle
, last
;
480 struct objfile
*objfile
;
482 ALL_OBJFILES (objfile
)
484 struct obj_unwind_info
*ui
;
486 ui
= OBJ_UNWIND_INFO (objfile
);
490 read_unwind_info (objfile
);
491 ui
= OBJ_UNWIND_INFO (objfile
);
494 /* First, check the cache */
497 && pc
>= ui
->cache
->region_start
498 && pc
<= ui
->cache
->region_end
)
501 /* Not in the cache, do a binary search */
506 while (first
<= last
)
508 middle
= (first
+ last
) / 2;
509 if (pc
>= ui
->table
[middle
].region_start
510 && pc
<= ui
->table
[middle
].region_end
)
512 ui
->cache
= &ui
->table
[middle
];
513 return &ui
->table
[middle
];
516 if (pc
< ui
->table
[middle
].region_start
)
521 } /* ALL_OBJFILES() */
525 /* start-sanitize-hpread */
526 /* Return the adjustment necessary to make for addresses on the stack
527 as presented by hpread.c.
529 This is necessary because of the stack direction on the PA and the
530 bizarre way in which someone (?) decided they wanted to handle
531 frame pointerless code in GDB. */
533 hpread_adjust_stack_address (func_addr
)
536 struct unwind_table_entry
*u
;
538 u
= find_unwind_entry (func_addr
);
542 return u
->Total_frame_size
<< 3;
544 /* end-sanitize-hpread */
546 /* Called to determine if PC is in an interrupt handler of some
550 pc_in_interrupt_handler (pc
)
553 struct unwind_table_entry
*u
;
554 struct minimal_symbol
*msym_us
;
556 u
= find_unwind_entry (pc
);
560 /* Oh joys. HPUX sets the interrupt bit for _sigreturn even though
561 its frame isn't a pure interrupt frame. Deal with this. */
562 msym_us
= lookup_minimal_symbol_by_pc (pc
);
564 return u
->HP_UX_interrupt_marker
&& !IN_SIGTRAMP (pc
, SYMBOL_NAME (msym_us
));
567 /* Called when no unwind descriptor was found for PC. Returns 1 if it
568 appears that PC is in a linker stub. */
571 pc_in_linker_stub (pc
)
574 int found_magic_instruction
= 0;
578 /* If unable to read memory, assume pc is not in a linker stub. */
579 if (target_read_memory (pc
, buf
, 4) != 0)
582 /* We are looking for something like
584 ; $$dyncall jams RP into this special spot in the frame (RP')
585 ; before calling the "call stub"
588 ldsid (rp),r1 ; Get space associated with RP into r1
589 mtsp r1,sp ; Move it into space register 0
590 be,n 0(sr0),rp) ; back to your regularly scheduled program
593 /* Maximum known linker stub size is 4 instructions. Search forward
594 from the given PC, then backward. */
595 for (i
= 0; i
< 4; i
++)
597 /* If we hit something with an unwind, stop searching this direction. */
599 if (find_unwind_entry (pc
+ i
* 4) != 0)
602 /* Check for ldsid (rp),r1 which is the magic instruction for a
603 return from a cross-space function call. */
604 if (read_memory_integer (pc
+ i
* 4, 4) == 0x004010a1)
606 found_magic_instruction
= 1;
609 /* Add code to handle long call/branch and argument relocation stubs
613 if (found_magic_instruction
!= 0)
616 /* Now look backward. */
617 for (i
= 0; i
< 4; i
++)
619 /* If we hit something with an unwind, stop searching this direction. */
621 if (find_unwind_entry (pc
- i
* 4) != 0)
624 /* Check for ldsid (rp),r1 which is the magic instruction for a
625 return from a cross-space function call. */
626 if (read_memory_integer (pc
- i
* 4, 4) == 0x004010a1)
628 found_magic_instruction
= 1;
631 /* Add code to handle long call/branch and argument relocation stubs
634 return found_magic_instruction
;
638 find_return_regnum(pc
)
641 struct unwind_table_entry
*u
;
643 u
= find_unwind_entry (pc
);
654 /* Return size of frame, or -1 if we should use a frame pointer. */
656 find_proc_framesize (pc
)
659 struct unwind_table_entry
*u
;
660 struct minimal_symbol
*msym_us
;
662 u
= find_unwind_entry (pc
);
666 if (pc_in_linker_stub (pc
))
667 /* Linker stubs have a zero size frame. */
673 msym_us
= lookup_minimal_symbol_by_pc (pc
);
675 /* If Save_SP is set, and we're not in an interrupt or signal caller,
676 then we have a frame pointer. Use it. */
677 if (u
->Save_SP
&& !pc_in_interrupt_handler (pc
)
678 && !IN_SIGTRAMP (pc
, SYMBOL_NAME (msym_us
)))
681 return u
->Total_frame_size
<< 3;
684 /* Return offset from sp at which rp is saved, or 0 if not saved. */
685 static int rp_saved
PARAMS ((CORE_ADDR
));
691 struct unwind_table_entry
*u
;
693 u
= find_unwind_entry (pc
);
697 if (pc_in_linker_stub (pc
))
698 /* This is the so-called RP'. */
706 else if (u
->stub_type
!= 0)
708 switch (u
->stub_type
)
712 case PARAMETER_RELOCATION
:
723 frameless_function_invocation (frame
)
724 struct frame_info
*frame
;
726 struct unwind_table_entry
*u
;
728 u
= find_unwind_entry (frame
->pc
);
733 return (u
->Total_frame_size
== 0 && u
->stub_type
== 0);
737 saved_pc_after_call (frame
)
738 struct frame_info
*frame
;
742 struct unwind_table_entry
*u
;
744 ret_regnum
= find_return_regnum (get_frame_pc (frame
));
745 pc
= read_register (ret_regnum
) & ~0x3;
747 /* If PC is in a linker stub, then we need to dig the address
748 the stub will return to out of the stack. */
749 u
= find_unwind_entry (pc
);
750 if (u
&& u
->stub_type
!= 0)
751 return frame_saved_pc (frame
);
757 frame_saved_pc (frame
)
758 struct frame_info
*frame
;
760 CORE_ADDR pc
= get_frame_pc (frame
);
761 struct unwind_table_entry
*u
;
763 /* BSD, HPUX & OSF1 all lay out the hardware state in the same manner
764 at the base of the frame in an interrupt handler. Registers within
765 are saved in the exact same order as GDB numbers registers. How
767 if (pc_in_interrupt_handler (pc
))
768 return read_memory_integer (frame
->frame
+ PC_REGNUM
* 4, 4) & ~0x3;
770 /* Deal with signal handler caller frames too. */
771 if (frame
->signal_handler_caller
)
774 FRAME_SAVED_PC_IN_SIGTRAMP (frame
, &rp
);
778 if (frameless_function_invocation (frame
))
782 ret_regnum
= find_return_regnum (pc
);
784 /* If the next frame is an interrupt frame or a signal
785 handler caller, then we need to look in the saved
786 register area to get the return pointer (the values
787 in the registers may not correspond to anything useful). */
789 && (frame
->next
->signal_handler_caller
790 || pc_in_interrupt_handler (frame
->next
->pc
)))
792 struct frame_saved_regs saved_regs
;
794 get_frame_saved_regs (frame
->next
, &saved_regs
);
795 if (read_memory_integer (saved_regs
.regs
[FLAGS_REGNUM
], 4) & 0x2)
797 pc
= read_memory_integer (saved_regs
.regs
[31], 4) & ~0x3;
799 /* Syscalls are really two frames. The syscall stub itself
800 with a return pointer in %rp and the kernel call with
801 a return pointer in %r31. We return the %rp variant
802 if %r31 is the same as frame->pc. */
804 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
807 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
810 pc
= read_register (ret_regnum
) & ~0x3;
817 rp_offset
= rp_saved (pc
);
818 /* Similar to code in frameless function case. If the next
819 frame is a signal or interrupt handler, then dig the right
820 information out of the saved register info. */
823 && (frame
->next
->signal_handler_caller
824 || pc_in_interrupt_handler (frame
->next
->pc
)))
826 struct frame_saved_regs saved_regs
;
828 get_frame_saved_regs (frame
->next
, &saved_regs
);
829 if (read_memory_integer (saved_regs
.regs
[FLAGS_REGNUM
], 4) & 0x2)
831 pc
= read_memory_integer (saved_regs
.regs
[31], 4) & ~0x3;
833 /* Syscalls are really two frames. The syscall stub itself
834 with a return pointer in %rp and the kernel call with
835 a return pointer in %r31. We return the %rp variant
836 if %r31 is the same as frame->pc. */
838 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
841 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
843 else if (rp_offset
== 0)
844 pc
= read_register (RP_REGNUM
) & ~0x3;
846 pc
= read_memory_integer (frame
->frame
+ rp_offset
, 4) & ~0x3;
849 /* If PC is inside a linker stub, then dig out the address the stub
851 u
= find_unwind_entry (pc
);
852 if (u
&& u
->stub_type
!= 0)
858 /* We need to correct the PC and the FP for the outermost frame when we are
862 init_extra_frame_info (fromleaf
, frame
)
864 struct frame_info
*frame
;
869 if (frame
->next
&& !fromleaf
)
872 /* If the next frame represents a frameless function invocation
873 then we have to do some adjustments that are normally done by
874 FRAME_CHAIN. (FRAME_CHAIN is not called in this case.) */
877 /* Find the framesize of *this* frame without peeking at the PC
878 in the current frame structure (it isn't set yet). */
879 framesize
= find_proc_framesize (FRAME_SAVED_PC (get_next_frame (frame
)));
881 /* Now adjust our base frame accordingly. If we have a frame pointer
882 use it, else subtract the size of this frame from the current
883 frame. (we always want frame->frame to point at the lowest address
886 frame
->frame
= read_register (FP_REGNUM
);
888 frame
->frame
-= framesize
;
892 flags
= read_register (FLAGS_REGNUM
);
893 if (flags
& 2) /* In system call? */
894 frame
->pc
= read_register (31) & ~0x3;
896 /* The outermost frame is always derived from PC-framesize
898 One might think frameless innermost frames should have
899 a frame->frame that is the same as the parent's frame->frame.
900 That is wrong; frame->frame in that case should be the *high*
901 address of the parent's frame. It's complicated as hell to
902 explain, but the parent *always* creates some stack space for
903 the child. So the child actually does have a frame of some
904 sorts, and its base is the high address in its parent's frame. */
905 framesize
= find_proc_framesize(frame
->pc
);
907 frame
->frame
= read_register (FP_REGNUM
);
909 frame
->frame
= read_register (SP_REGNUM
) - framesize
;
912 /* Given a GDB frame, determine the address of the calling function's frame.
913 This will be used to create a new GDB frame struct, and then
914 INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame.
916 This may involve searching through prologues for several functions
917 at boundaries where GCC calls HP C code, or where code which has
918 a frame pointer calls code without a frame pointer. */
922 struct frame_info
*frame
;
924 int my_framesize
, caller_framesize
;
925 struct unwind_table_entry
*u
;
926 CORE_ADDR frame_base
;
928 /* Handle HPUX, BSD, and OSF1 style interrupt frames first. These
929 are easy; at *sp we have a full save state strucutre which we can
930 pull the old stack pointer from. Also see frame_saved_pc for
931 code to dig a saved PC out of the save state structure. */
932 if (pc_in_interrupt_handler (frame
->pc
))
933 frame_base
= read_memory_integer (frame
->frame
+ SP_REGNUM
* 4, 4);
934 else if (frame
->signal_handler_caller
)
936 FRAME_BASE_BEFORE_SIGTRAMP (frame
, &frame_base
);
939 frame_base
= frame
->frame
;
941 /* Get frame sizes for the current frame and the frame of the
943 my_framesize
= find_proc_framesize (frame
->pc
);
944 caller_framesize
= find_proc_framesize (FRAME_SAVED_PC(frame
));
946 /* If caller does not have a frame pointer, then its frame
947 can be found at current_frame - caller_framesize. */
948 if (caller_framesize
!= -1)
949 return frame_base
- caller_framesize
;
951 /* Both caller and callee have frame pointers and are GCC compiled
952 (SAVE_SP bit in unwind descriptor is on for both functions.
953 The previous frame pointer is found at the top of the current frame. */
954 if (caller_framesize
== -1 && my_framesize
== -1)
955 return read_memory_integer (frame_base
, 4);
957 /* Caller has a frame pointer, but callee does not. This is a little
958 more difficult as GCC and HP C lay out locals and callee register save
959 areas very differently.
961 The previous frame pointer could be in a register, or in one of
962 several areas on the stack.
964 Walk from the current frame to the innermost frame examining
965 unwind descriptors to determine if %r3 ever gets saved into the
966 stack. If so return whatever value got saved into the stack.
967 If it was never saved in the stack, then the value in %r3 is still
970 We use information from unwind descriptors to determine if %r3
971 is saved into the stack (Entry_GR field has this information). */
975 u
= find_unwind_entry (frame
->pc
);
979 /* We could find this information by examining prologues. I don't
980 think anyone has actually written any tools (not even "strip")
981 which leave them out of an executable, so maybe this is a moot
983 warning ("Unable to find unwind for PC 0x%x -- Help!", frame
->pc
);
987 /* Entry_GR specifies the number of callee-saved general registers
988 saved in the stack. It starts at %r3, so %r3 would be 1. */
989 if (u
->Entry_GR
>= 1 || u
->Save_SP
990 || frame
->signal_handler_caller
991 || pc_in_interrupt_handler (frame
->pc
))
999 /* We may have walked down the chain into a function with a frame
1002 && !frame
->signal_handler_caller
1003 && !pc_in_interrupt_handler (frame
->pc
))
1004 return read_memory_integer (frame
->frame
, 4);
1005 /* %r3 was saved somewhere in the stack. Dig it out. */
1008 struct frame_saved_regs saved_regs
;
1010 get_frame_saved_regs (frame
, &saved_regs
);
1011 return read_memory_integer (saved_regs
.regs
[FP_REGNUM
], 4);
1016 /* The value in %r3 was never saved into the stack (thus %r3 still
1017 holds the value of the previous frame pointer). */
1018 return read_register (FP_REGNUM
);
1023 /* To see if a frame chain is valid, see if the caller looks like it
1024 was compiled with gcc. */
1027 frame_chain_valid (chain
, thisframe
)
1029 struct frame_info
*thisframe
;
1031 struct minimal_symbol
*msym_us
;
1032 struct minimal_symbol
*msym_start
;
1033 struct unwind_table_entry
*u
, *next_u
= NULL
;
1034 struct frame_info
*next
;
1039 u
= find_unwind_entry (thisframe
->pc
);
1044 /* We can't just check that the same of msym_us is "_start", because
1045 someone idiotically decided that they were going to make a Ltext_end
1046 symbol with the same address. This Ltext_end symbol is totally
1047 indistinguishable (as nearly as I can tell) from the symbol for a function
1048 which is (legitimately, since it is in the user's namespace)
1049 named Ltext_end, so we can't just ignore it. */
1050 msym_us
= lookup_minimal_symbol_by_pc (FRAME_SAVED_PC (thisframe
));
1051 msym_start
= lookup_minimal_symbol ("_start", NULL
);
1054 && SYMBOL_VALUE_ADDRESS (msym_us
) == SYMBOL_VALUE_ADDRESS (msym_start
))
1057 next
= get_next_frame (thisframe
);
1059 next_u
= find_unwind_entry (next
->pc
);
1061 /* If this frame does not save SP, has no stack, isn't a stub,
1062 and doesn't "call" an interrupt routine or signal handler caller,
1063 then its not valid. */
1064 if (u
->Save_SP
|| u
->Total_frame_size
|| u
->stub_type
!= 0
1065 || (thisframe
->next
&& thisframe
->next
->signal_handler_caller
)
1066 || (next_u
&& next_u
->HP_UX_interrupt_marker
))
1069 if (pc_in_linker_stub (thisframe
->pc
))
1076 * These functions deal with saving and restoring register state
1077 * around a function call in the inferior. They keep the stack
1078 * double-word aligned; eventually, on an hp700, the stack will have
1079 * to be aligned to a 64-byte boundary.
1085 register CORE_ADDR sp
;
1086 register int regnum
;
1090 /* Space for "arguments"; the RP goes in here. */
1091 sp
= read_register (SP_REGNUM
) + 48;
1092 int_buffer
= read_register (RP_REGNUM
) | 0x3;
1093 write_memory (sp
- 20, (char *)&int_buffer
, 4);
1095 int_buffer
= read_register (FP_REGNUM
);
1096 write_memory (sp
, (char *)&int_buffer
, 4);
1098 write_register (FP_REGNUM
, sp
);
1102 for (regnum
= 1; regnum
< 32; regnum
++)
1103 if (regnum
!= RP_REGNUM
&& regnum
!= FP_REGNUM
)
1104 sp
= push_word (sp
, read_register (regnum
));
1108 for (regnum
= FP0_REGNUM
; regnum
< NUM_REGS
; regnum
++)
1110 read_register_bytes (REGISTER_BYTE (regnum
), (char *)&freg_buffer
, 8);
1111 sp
= push_bytes (sp
, (char *)&freg_buffer
, 8);
1113 sp
= push_word (sp
, read_register (IPSW_REGNUM
));
1114 sp
= push_word (sp
, read_register (SAR_REGNUM
));
1115 sp
= push_word (sp
, read_register (PCOQ_HEAD_REGNUM
));
1116 sp
= push_word (sp
, read_register (PCSQ_HEAD_REGNUM
));
1117 sp
= push_word (sp
, read_register (PCOQ_TAIL_REGNUM
));
1118 sp
= push_word (sp
, read_register (PCSQ_TAIL_REGNUM
));
1119 write_register (SP_REGNUM
, sp
);
1122 find_dummy_frame_regs (frame
, frame_saved_regs
)
1123 struct frame_info
*frame
;
1124 struct frame_saved_regs
*frame_saved_regs
;
1126 CORE_ADDR fp
= frame
->frame
;
1129 frame_saved_regs
->regs
[RP_REGNUM
] = fp
- 20 & ~0x3;
1130 frame_saved_regs
->regs
[FP_REGNUM
] = fp
;
1131 frame_saved_regs
->regs
[1] = fp
+ 8;
1133 for (fp
+= 12, i
= 3; i
< 32; i
++)
1137 frame_saved_regs
->regs
[i
] = fp
;
1143 for (i
= FP0_REGNUM
; i
< NUM_REGS
; i
++, fp
+= 8)
1144 frame_saved_regs
->regs
[i
] = fp
;
1146 frame_saved_regs
->regs
[IPSW_REGNUM
] = fp
;
1147 frame_saved_regs
->regs
[SAR_REGNUM
] = fp
+ 4;
1148 frame_saved_regs
->regs
[PCOQ_HEAD_REGNUM
] = fp
+ 8;
1149 frame_saved_regs
->regs
[PCSQ_HEAD_REGNUM
] = fp
+ 12;
1150 frame_saved_regs
->regs
[PCOQ_TAIL_REGNUM
] = fp
+ 16;
1151 frame_saved_regs
->regs
[PCSQ_TAIL_REGNUM
] = fp
+ 20;
1157 register struct frame_info
*frame
= get_current_frame ();
1158 register CORE_ADDR fp
;
1159 register int regnum
;
1160 struct frame_saved_regs fsr
;
1163 fp
= FRAME_FP (frame
);
1164 get_frame_saved_regs (frame
, &fsr
);
1166 #ifndef NO_PC_SPACE_QUEUE_RESTORE
1167 if (fsr
.regs
[IPSW_REGNUM
]) /* Restoring a call dummy frame */
1168 restore_pc_queue (&fsr
);
1171 for (regnum
= 31; regnum
> 0; regnum
--)
1172 if (fsr
.regs
[regnum
])
1173 write_register (regnum
, read_memory_integer (fsr
.regs
[regnum
], 4));
1175 for (regnum
= NUM_REGS
- 1; regnum
>= FP0_REGNUM
; regnum
--)
1176 if (fsr
.regs
[regnum
])
1178 read_memory (fsr
.regs
[regnum
], (char *)&freg_buffer
, 8);
1179 write_register_bytes (REGISTER_BYTE (regnum
), (char *)&freg_buffer
, 8);
1182 if (fsr
.regs
[IPSW_REGNUM
])
1183 write_register (IPSW_REGNUM
,
1184 read_memory_integer (fsr
.regs
[IPSW_REGNUM
], 4));
1186 if (fsr
.regs
[SAR_REGNUM
])
1187 write_register (SAR_REGNUM
,
1188 read_memory_integer (fsr
.regs
[SAR_REGNUM
], 4));
1190 /* If the PC was explicitly saved, then just restore it. */
1191 if (fsr
.regs
[PCOQ_TAIL_REGNUM
])
1192 write_register (PCOQ_TAIL_REGNUM
,
1193 read_memory_integer (fsr
.regs
[PCOQ_TAIL_REGNUM
], 4));
1195 /* Else use the value in %rp to set the new PC. */
1197 target_write_pc (read_register (RP_REGNUM
), 0);
1199 write_register (FP_REGNUM
, read_memory_integer (fp
, 4));
1201 if (fsr
.regs
[IPSW_REGNUM
]) /* call dummy */
1202 write_register (SP_REGNUM
, fp
- 48);
1204 write_register (SP_REGNUM
, fp
);
1206 flush_cached_frames ();
1210 * After returning to a dummy on the stack, restore the instruction
1211 * queue space registers. */
1214 restore_pc_queue (fsr
)
1215 struct frame_saved_regs
*fsr
;
1217 CORE_ADDR pc
= read_pc ();
1218 CORE_ADDR new_pc
= read_memory_integer (fsr
->regs
[PCOQ_HEAD_REGNUM
], 4);
1220 struct target_waitstatus w
;
1223 /* Advance past break instruction in the call dummy. */
1224 write_register (PCOQ_HEAD_REGNUM
, pc
+ 4);
1225 write_register (PCOQ_TAIL_REGNUM
, pc
+ 8);
1228 * HPUX doesn't let us set the space registers or the space
1229 * registers of the PC queue through ptrace. Boo, hiss.
1230 * Conveniently, the call dummy has this sequence of instructions
1235 * So, load up the registers and single step until we are in the
1239 write_register (21, read_memory_integer (fsr
->regs
[PCSQ_HEAD_REGNUM
], 4));
1240 write_register (22, new_pc
);
1242 for (insn_count
= 0; insn_count
< 3; insn_count
++)
1244 /* FIXME: What if the inferior gets a signal right now? Want to
1245 merge this into wait_for_inferior (as a special kind of
1246 watchpoint? By setting a breakpoint at the end? Is there
1247 any other choice? Is there *any* way to do this stuff with
1248 ptrace() or some equivalent?). */
1250 target_wait (inferior_pid
, &w
);
1252 if (w
.kind
== TARGET_WAITKIND_SIGNALLED
)
1254 stop_signal
= w
.value
.sig
;
1255 terminal_ours_for_output ();
1256 printf_unfiltered ("\nProgram terminated with signal %s, %s.\n",
1257 target_signal_to_name (stop_signal
),
1258 target_signal_to_string (stop_signal
));
1259 gdb_flush (gdb_stdout
);
1263 target_terminal_ours ();
1264 target_fetch_registers (-1);
1269 hppa_push_arguments (nargs
, args
, sp
, struct_return
, struct_addr
)
1274 CORE_ADDR struct_addr
;
1276 /* array of arguments' offsets */
1277 int *offset
= (int *)alloca(nargs
* sizeof (int));
1281 for (i
= 0; i
< nargs
; i
++)
1283 /* Coerce chars to int & float to double if necessary */
1284 args
[i
] = value_arg_coerce (args
[i
]);
1286 cum
+= TYPE_LENGTH (VALUE_TYPE (args
[i
]));
1288 /* value must go at proper alignment. Assume alignment is a
1290 alignment
= hppa_alignof (VALUE_TYPE (args
[i
]));
1291 if (cum
% alignment
)
1292 cum
= (cum
+ alignment
) & -alignment
;
1295 sp
+= max ((cum
+ 7) & -8, 16);
1297 for (i
= 0; i
< nargs
; i
++)
1298 write_memory (sp
+ offset
[i
], VALUE_CONTENTS (args
[i
]),
1299 TYPE_LENGTH (VALUE_TYPE (args
[i
])));
1302 write_register (28, struct_addr
);
1307 * Insert the specified number of args and function address
1308 * into a call sequence of the above form stored at DUMMYNAME.
1310 * On the hppa we need to call the stack dummy through $$dyncall.
1311 * Therefore our version of FIX_CALL_DUMMY takes an extra argument,
1312 * real_pc, which is the location where gdb should start up the
1313 * inferior to do the function call.
1317 hppa_fix_call_dummy (dummy
, pc
, fun
, nargs
, args
, type
, gcc_p
)
1326 CORE_ADDR dyncall_addr
, sr4export_addr
;
1327 struct minimal_symbol
*msymbol
;
1328 int flags
= read_register (FLAGS_REGNUM
);
1329 struct unwind_table_entry
*u
;
1331 msymbol
= lookup_minimal_symbol ("$$dyncall", (struct objfile
*) NULL
);
1332 if (msymbol
== NULL
)
1333 error ("Can't find an address for $$dyncall trampoline");
1335 dyncall_addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
1337 /* FUN could be a procedure label, in which case we have to get
1338 its real address and the value of its GOT/DP. */
1341 /* Get the GOT/DP value for the target function. It's
1342 at *(fun+4). Note the call dummy is *NOT* allowed to
1343 trash %r19 before calling the target function. */
1344 write_register (19, read_memory_integer ((fun
& ~0x3) + 4, 4));
1346 /* Now get the real address for the function we are calling, it's
1348 fun
= (CORE_ADDR
) read_memory_integer (fun
& ~0x3, 4);
1351 /* If we are calling an import stub (eg calling into a dynamic library)
1352 then have sr4export call the magic __d_plt_call routine which is linked
1353 in from end.o. (You can't use _sr4export to call the import stub as
1354 the value in sp-24 will get fried and you end up returning to the
1355 wrong location. You can't call the import stub directly as the code
1356 to bind the PLT entry to a function can't return to a stack address.) */
1357 u
= find_unwind_entry (fun
);
1358 if (u
&& u
->stub_type
== IMPORT
)
1361 msymbol
= lookup_minimal_symbol ("__d_plt_call", (struct objfile
*) NULL
);
1362 if (msymbol
== NULL
)
1363 error ("Can't find an address for __d_plt_call trampoline");
1365 /* This is where sr4export will jump to. */
1366 new_fun
= SYMBOL_VALUE_ADDRESS (msymbol
);
1368 /* We have to store the address of the stub in __shlib_funcptr. */
1369 msymbol
= lookup_minimal_symbol ("__shlib_funcptr",
1370 (struct objfile
*)NULL
);
1371 if (msymbol
== NULL
)
1372 error ("Can't find an address for __shlib_funcptr");
1374 target_write_memory (SYMBOL_VALUE_ADDRESS (msymbol
), (char *)&fun
, 4);
1379 /* We still need sr4export's address too. */
1380 msymbol
= lookup_minimal_symbol ("_sr4export", (struct objfile
*) NULL
);
1381 if (msymbol
== NULL
)
1382 error ("Can't find an address for _sr4export trampoline");
1384 sr4export_addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
1386 store_unsigned_integer
1387 (&dummy
[9*REGISTER_SIZE
],
1389 deposit_21 (fun
>> 11,
1390 extract_unsigned_integer (&dummy
[9*REGISTER_SIZE
],
1392 store_unsigned_integer
1393 (&dummy
[10*REGISTER_SIZE
],
1395 deposit_14 (fun
& MASK_11
,
1396 extract_unsigned_integer (&dummy
[10*REGISTER_SIZE
],
1398 store_unsigned_integer
1399 (&dummy
[12*REGISTER_SIZE
],
1401 deposit_21 (sr4export_addr
>> 11,
1402 extract_unsigned_integer (&dummy
[12*REGISTER_SIZE
],
1404 store_unsigned_integer
1405 (&dummy
[13*REGISTER_SIZE
],
1407 deposit_14 (sr4export_addr
& MASK_11
,
1408 extract_unsigned_integer (&dummy
[13*REGISTER_SIZE
],
1411 write_register (22, pc
);
1413 /* If we are in a syscall, then we should call the stack dummy
1414 directly. $$dyncall is not needed as the kernel sets up the
1415 space id registers properly based on the value in %r31. In
1416 fact calling $$dyncall will not work because the value in %r22
1417 will be clobbered on the syscall exit path. */
1421 return dyncall_addr
;
1425 /* Get the PC from %r31 if currently in a syscall. Also mask out privilege
1429 target_read_pc (pid
)
1432 int flags
= read_register (FLAGS_REGNUM
);
1435 return read_register (31) & ~0x3;
1436 return read_register (PC_REGNUM
) & ~0x3;
1439 /* Write out the PC. If currently in a syscall, then also write the new
1440 PC value into %r31. */
1443 target_write_pc (v
, pid
)
1447 int flags
= read_register (FLAGS_REGNUM
);
1449 /* If in a syscall, then set %r31. Also make sure to get the
1450 privilege bits set correctly. */
1452 write_register (31, (long) (v
| 0x3));
1454 write_register (PC_REGNUM
, (long) v
);
1455 write_register (NPC_REGNUM
, (long) v
+ 4);
1458 /* return the alignment of a type in bytes. Structures have the maximum
1459 alignment required by their fields. */
1465 int max_align
, align
, i
;
1466 switch (TYPE_CODE (arg
))
1471 return TYPE_LENGTH (arg
);
1472 case TYPE_CODE_ARRAY
:
1473 return hppa_alignof (TYPE_FIELD_TYPE (arg
, 0));
1474 case TYPE_CODE_STRUCT
:
1475 case TYPE_CODE_UNION
:
1477 for (i
= 0; i
< TYPE_NFIELDS (arg
); i
++)
1479 /* Bit fields have no real alignment. */
1480 if (!TYPE_FIELD_BITPOS (arg
, i
))
1482 align
= hppa_alignof (TYPE_FIELD_TYPE (arg
, i
));
1483 max_align
= max (max_align
, align
);
1492 /* Print the register regnum, or all registers if regnum is -1 */
1494 pa_do_registers_info (regnum
, fpregs
)
1498 char raw_regs
[REGISTER_BYTES
];
1501 for (i
= 0; i
< NUM_REGS
; i
++)
1502 read_relative_register_raw_bytes (i
, raw_regs
+ REGISTER_BYTE (i
));
1504 pa_print_registers (raw_regs
, regnum
, fpregs
);
1505 else if (regnum
< FP0_REGNUM
)
1506 printf_unfiltered ("%s %x\n", reg_names
[regnum
], *(long *)(raw_regs
+
1507 REGISTER_BYTE (regnum
)));
1509 pa_print_fp_reg (regnum
);
1512 pa_print_registers (raw_regs
, regnum
, fpregs
)
1519 for (i
= 0; i
< 18; i
++)
1520 printf_unfiltered ("%8.8s: %8x %8.8s: %8x %8.8s: %8x %8.8s: %8x\n",
1522 *(int *)(raw_regs
+ REGISTER_BYTE (i
)),
1524 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 18)),
1526 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 36)),
1528 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 54)));
1531 for (i
= 72; i
< NUM_REGS
; i
++)
1532 pa_print_fp_reg (i
);
1538 unsigned char raw_buffer
[MAX_REGISTER_RAW_SIZE
];
1539 unsigned char virtual_buffer
[MAX_REGISTER_VIRTUAL_SIZE
];
1541 /* Get 32bits of data. */
1542 read_relative_register_raw_bytes (i
, raw_buffer
);
1544 /* Put it in the buffer. No conversions are ever necessary. */
1545 memcpy (virtual_buffer
, raw_buffer
, REGISTER_RAW_SIZE (i
));
1547 fputs_filtered (reg_names
[i
], gdb_stdout
);
1548 print_spaces_filtered (8 - strlen (reg_names
[i
]), gdb_stdout
);
1549 fputs_filtered ("(single precision) ", gdb_stdout
);
1551 val_print (REGISTER_VIRTUAL_TYPE (i
), virtual_buffer
, 0, gdb_stdout
, 0,
1552 1, 0, Val_pretty_default
);
1553 printf_filtered ("\n");
1555 /* If "i" is even, then this register can also be a double-precision
1556 FP register. Dump it out as such. */
1559 /* Get the data in raw format for the 2nd half. */
1560 read_relative_register_raw_bytes (i
+ 1, raw_buffer
);
1562 /* Copy it into the appropriate part of the virtual buffer. */
1563 memcpy (virtual_buffer
+ REGISTER_RAW_SIZE (i
), raw_buffer
,
1564 REGISTER_RAW_SIZE (i
));
1566 /* Dump it as a double. */
1567 fputs_filtered (reg_names
[i
], gdb_stdout
);
1568 print_spaces_filtered (8 - strlen (reg_names
[i
]), gdb_stdout
);
1569 fputs_filtered ("(double precision) ", gdb_stdout
);
1571 val_print (builtin_type_double
, virtual_buffer
, 0, gdb_stdout
, 0,
1572 1, 0, Val_pretty_default
);
1573 printf_filtered ("\n");
1577 /* Figure out if PC is in a trampoline, and if so find out where
1578 the trampoline will jump to. If not in a trampoline, return zero.
1580 Simple code examination probably is not a good idea since the code
1581 sequences in trampolines can also appear in user code.
1583 We use unwinds and information from the minimal symbol table to
1584 determine when we're in a trampoline. This won't work for ELF
1585 (yet) since it doesn't create stub unwind entries. Whether or
1586 not ELF will create stub unwinds or normal unwinds for linker
1587 stubs is still being debated.
1589 This should handle simple calls through dyncall or sr4export,
1590 long calls, argument relocation stubs, and dyncall/sr4export
1591 calling an argument relocation stub. It even handles some stubs
1592 used in dynamic executables. */
1595 skip_trampoline_code (pc
, name
)
1600 long prev_inst
, curr_inst
, loc
;
1601 static CORE_ADDR dyncall
= 0;
1602 static CORE_ADDR sr4export
= 0;
1603 struct minimal_symbol
*msym
;
1604 struct unwind_table_entry
*u
;
1606 /* FIXME XXX - dyncall and sr4export must be initialized whenever we get a
1611 msym
= lookup_minimal_symbol ("$$dyncall", NULL
);
1613 dyncall
= SYMBOL_VALUE_ADDRESS (msym
);
1620 msym
= lookup_minimal_symbol ("_sr4export", NULL
);
1622 sr4export
= SYMBOL_VALUE_ADDRESS (msym
);
1627 /* Addresses passed to dyncall may *NOT* be the actual address
1628 of the function. So we may have to do something special. */
1631 pc
= (CORE_ADDR
) read_register (22);
1633 /* If bit 30 (counting from the left) is on, then pc is the address of
1634 the PLT entry for this function, not the address of the function
1635 itself. Bit 31 has meaning too, but only for MPE. */
1637 pc
= (CORE_ADDR
) read_memory_integer (pc
& ~0x3, 4);
1639 else if (pc
== sr4export
)
1640 pc
= (CORE_ADDR
) (read_register (22));
1642 /* Get the unwind descriptor corresponding to PC, return zero
1643 if no unwind was found. */
1644 u
= find_unwind_entry (pc
);
1648 /* If this isn't a linker stub, then return now. */
1649 if (u
->stub_type
== 0)
1650 return orig_pc
== pc
? 0 : pc
& ~0x3;
1652 /* It's a stub. Search for a branch and figure out where it goes.
1653 Note we have to handle multi insn branch sequences like ldil;ble.
1654 Most (all?) other branches can be determined by examining the contents
1655 of certain registers and the stack. */
1661 /* Make sure we haven't walked outside the range of this stub. */
1662 if (u
!= find_unwind_entry (loc
))
1664 warning ("Unable to find branch in linker stub");
1665 return orig_pc
== pc
? 0 : pc
& ~0x3;
1668 prev_inst
= curr_inst
;
1669 curr_inst
= read_memory_integer (loc
, 4);
1671 /* Does it look like a branch external using %r1? Then it's the
1672 branch from the stub to the actual function. */
1673 if ((curr_inst
& 0xffe0e000) == 0xe0202000)
1675 /* Yup. See if the previous instruction loaded
1676 a value into %r1. If so compute and return the jump address. */
1677 if ((prev_inst
& 0xffe00000) == 0x20200000)
1678 return (extract_21 (prev_inst
) + extract_17 (curr_inst
)) & ~0x3;
1681 warning ("Unable to find ldil X,%%r1 before ble Y(%%sr4,%%r1).");
1682 return orig_pc
== pc
? 0 : pc
& ~0x3;
1686 /* Does it look like bl X,%rp or bl X,%r0? Another way to do a
1687 branch from the stub to the actual function. */
1688 else if ((curr_inst
& 0xffe0e000) == 0xe8400000
1689 || (curr_inst
& 0xffe0e000) == 0xe8000000)
1690 return (loc
+ extract_17 (curr_inst
) + 8) & ~0x3;
1692 /* Does it look like bv (rp)? Note this depends on the
1693 current stack pointer being the same as the stack
1694 pointer in the stub itself! This is a branch on from the
1695 stub back to the original caller. */
1696 else if ((curr_inst
& 0xffe0e000) == 0xe840c000)
1698 /* Yup. See if the previous instruction loaded
1700 if (prev_inst
== 0x4bc23ff1)
1701 return (read_memory_integer
1702 (read_register (SP_REGNUM
) - 8, 4)) & ~0x3;
1705 warning ("Unable to find restore of %%rp before bv (%%rp).");
1706 return orig_pc
== pc
? 0 : pc
& ~0x3;
1710 /* What about be,n 0(sr0,%rp)? It's just another way we return to
1711 the original caller from the stub. Used in dynamic executables. */
1712 else if (curr_inst
== 0xe0400002)
1714 /* The value we jump to is sitting in sp - 24. But that's
1715 loaded several instructions before the be instruction.
1716 I guess we could check for the previous instruction being
1717 mtsp %r1,%sr0 if we want to do sanity checking. */
1718 return (read_memory_integer
1719 (read_register (SP_REGNUM
) - 24, 4)) & ~0x3;
1722 /* Haven't found the branch yet, but we're still in the stub.
1728 /* For the given instruction (INST), return any adjustment it makes
1729 to the stack pointer or zero for no adjustment.
1731 This only handles instructions commonly found in prologues. */
1734 prologue_inst_adjust_sp (inst
)
1737 /* This must persist across calls. */
1738 static int save_high21
;
1740 /* The most common way to perform a stack adjustment ldo X(sp),sp */
1741 if ((inst
& 0xffffc000) == 0x37de0000)
1742 return extract_14 (inst
);
1745 if ((inst
& 0xffe00000) == 0x6fc00000)
1746 return extract_14 (inst
);
1748 /* addil high21,%r1; ldo low11,(%r1),%r30)
1749 save high bits in save_high21 for later use. */
1750 if ((inst
& 0xffe00000) == 0x28200000)
1752 save_high21
= extract_21 (inst
);
1756 if ((inst
& 0xffff0000) == 0x343e0000)
1757 return save_high21
+ extract_14 (inst
);
1759 /* fstws as used by the HP compilers. */
1760 if ((inst
& 0xffffffe0) == 0x2fd01220)
1761 return extract_5_load (inst
);
1763 /* No adjustment. */
1767 /* Return nonzero if INST is a branch of some kind, else return zero. */
1797 /* Return the register number for a GR which is saved by INST or
1798 zero it INST does not save a GR. */
1801 inst_saves_gr (inst
)
1804 /* Does it look like a stw? */
1805 if ((inst
>> 26) == 0x1a)
1806 return extract_5R_store (inst
);
1808 /* Does it look like a stwm? GCC & HPC may use this in prologues. */
1809 if ((inst
>> 26) == 0x1b)
1810 return extract_5R_store (inst
);
1812 /* Does it look like sth or stb? HPC versions 9.0 and later use these
1814 if ((inst
>> 26) == 0x19 || (inst
>> 26) == 0x18)
1815 return extract_5R_store (inst
);
1820 /* Return the register number for a FR which is saved by INST or
1821 zero it INST does not save a FR.
1823 Note we only care about full 64bit register stores (that's the only
1824 kind of stores the prologue will use).
1826 FIXME: What about argument stores with the HP compiler in ANSI mode? */
1829 inst_saves_fr (inst
)
1832 if ((inst
& 0xfc00dfc0) == 0x2c001200)
1833 return extract_5r_store (inst
);
1837 /* Advance PC across any function entry prologue instructions
1838 to reach some "real" code.
1840 Use information in the unwind table to determine what exactly should
1841 be in the prologue. */
1848 unsigned long inst
, stack_remaining
, save_gr
, save_fr
, save_rp
, save_sp
;
1849 unsigned long args_stored
, status
, i
;
1850 struct unwind_table_entry
*u
;
1852 u
= find_unwind_entry (pc
);
1856 /* If we are not at the beginning of a function, then return now. */
1857 if ((pc
& ~0x3) != u
->region_start
)
1860 /* This is how much of a frame adjustment we need to account for. */
1861 stack_remaining
= u
->Total_frame_size
<< 3;
1863 /* Magic register saves we want to know about. */
1864 save_rp
= u
->Save_RP
;
1865 save_sp
= u
->Save_SP
;
1867 /* An indication that args may be stored into the stack. Unfortunately
1868 the HPUX compilers tend to set this in cases where no args were
1870 args_stored
= u
->Args_stored
;
1872 /* Turn the Entry_GR field into a bitmask. */
1874 for (i
= 3; i
< u
->Entry_GR
+ 3; i
++)
1876 /* Frame pointer gets saved into a special location. */
1877 if (u
->Save_SP
&& i
== FP_REGNUM
)
1880 save_gr
|= (1 << i
);
1883 /* Turn the Entry_FR field into a bitmask too. */
1885 for (i
= 12; i
< u
->Entry_FR
+ 12; i
++)
1886 save_fr
|= (1 << i
);
1888 /* Loop until we find everything of interest or hit a branch.
1890 For unoptimized GCC code and for any HP CC code this will never ever
1891 examine any user instructions.
1893 For optimzied GCC code we're faced with problems. GCC will schedule
1894 its prologue and make prologue instructions available for delay slot
1895 filling. The end result is user code gets mixed in with the prologue
1896 and a prologue instruction may be in the delay slot of the first branch
1899 Some unexpected things are expected with debugging optimized code, so
1900 we allow this routine to walk past user instructions in optimized
1902 while (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0
1905 unsigned int reg_num
;
1906 unsigned long old_stack_remaining
, old_save_gr
, old_save_fr
;
1907 unsigned long old_save_rp
, old_save_sp
, old_args_stored
, next_inst
;
1909 /* Save copies of all the triggers so we can compare them later
1911 old_save_gr
= save_gr
;
1912 old_save_fr
= save_fr
;
1913 old_save_rp
= save_rp
;
1914 old_save_sp
= save_sp
;
1915 old_stack_remaining
= stack_remaining
;
1917 status
= target_read_memory (pc
, buf
, 4);
1918 inst
= extract_unsigned_integer (buf
, 4);
1924 /* Note the interesting effects of this instruction. */
1925 stack_remaining
-= prologue_inst_adjust_sp (inst
);
1927 /* There is only one instruction used for saving RP into the stack. */
1928 if (inst
== 0x6bc23fd9)
1931 /* This is the only way we save SP into the stack. At this time
1932 the HP compilers never bother to save SP into the stack. */
1933 if ((inst
& 0xffffc000) == 0x6fc10000)
1936 /* Account for general and floating-point register saves. */
1937 reg_num
= inst_saves_gr (inst
);
1938 save_gr
&= ~(1 << reg_num
);
1940 /* Ugh. Also account for argument stores into the stack.
1941 Unfortunately args_stored only tells us that some arguments
1942 where stored into the stack. Not how many or what kind!
1944 This is a kludge as on the HP compiler sets this bit and it
1945 never does prologue scheduling. So once we see one, skip past
1946 all of them. We have similar code for the fp arg stores below.
1948 FIXME. Can still die if we have a mix of GR and FR argument
1950 if (reg_num
>= 23 && reg_num
<= 26)
1952 while (reg_num
>= 23 && reg_num
<= 26)
1955 status
= target_read_memory (pc
, buf
, 4);
1956 inst
= extract_unsigned_integer (buf
, 4);
1959 reg_num
= inst_saves_gr (inst
);
1965 reg_num
= inst_saves_fr (inst
);
1966 save_fr
&= ~(1 << reg_num
);
1968 status
= target_read_memory (pc
+ 4, buf
, 4);
1969 next_inst
= extract_unsigned_integer (buf
, 4);
1975 /* We've got to be read to handle the ldo before the fp register
1977 if ((inst
& 0xfc000000) == 0x34000000
1978 && inst_saves_fr (next_inst
) >= 4
1979 && inst_saves_fr (next_inst
) <= 7)
1981 /* So we drop into the code below in a reasonable state. */
1982 reg_num
= inst_saves_fr (next_inst
);
1986 /* Ugh. Also account for argument stores into the stack.
1987 This is a kludge as on the HP compiler sets this bit and it
1988 never does prologue scheduling. So once we see one, skip past
1990 if (reg_num
>= 4 && reg_num
<= 7)
1992 while (reg_num
>= 4 && reg_num
<= 7)
1995 status
= target_read_memory (pc
, buf
, 4);
1996 inst
= extract_unsigned_integer (buf
, 4);
1999 if ((inst
& 0xfc000000) != 0x34000000)
2001 status
= target_read_memory (pc
+ 4, buf
, 4);
2002 next_inst
= extract_unsigned_integer (buf
, 4);
2005 reg_num
= inst_saves_fr (next_inst
);
2011 /* Quit if we hit any kind of branch. This can happen if a prologue
2012 instruction is in the delay slot of the first call/branch. */
2013 if (is_branch (inst
))
2016 /* What a crock. The HP compilers set args_stored even if no
2017 arguments were stored into the stack (boo hiss). This could
2018 cause this code to then skip a bunch of user insns (up to the
2021 To combat this we try to identify when args_stored was bogusly
2022 set and clear it. We only do this when args_stored is nonzero,
2023 all other resources are accounted for, and nothing changed on
2026 && ! (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0)
2027 && old_save_gr
== save_gr
&& old_save_fr
== save_fr
2028 && old_save_rp
== save_rp
&& old_save_sp
== save_sp
2029 && old_stack_remaining
== stack_remaining
)
2039 /* Put here the code to store, into a struct frame_saved_regs,
2040 the addresses of the saved registers of frame described by FRAME_INFO.
2041 This includes special registers such as pc and fp saved in special
2042 ways in the stack frame. sp is even more special:
2043 the address we return for it IS the sp for the next frame. */
2046 hppa_frame_find_saved_regs (frame_info
, frame_saved_regs
)
2047 struct frame_info
*frame_info
;
2048 struct frame_saved_regs
*frame_saved_regs
;
2051 struct unwind_table_entry
*u
;
2052 unsigned long inst
, stack_remaining
, save_gr
, save_fr
, save_rp
, save_sp
;
2057 /* Zero out everything. */
2058 memset (frame_saved_regs
, '\0', sizeof (struct frame_saved_regs
));
2060 /* Call dummy frames always look the same, so there's no need to
2061 examine the dummy code to determine locations of saved registers;
2062 instead, let find_dummy_frame_regs fill in the correct offsets
2063 for the saved registers. */
2064 if ((frame_info
->pc
>= frame_info
->frame
2065 && frame_info
->pc
<= (frame_info
->frame
+ CALL_DUMMY_LENGTH
2066 + 32 * 4 + (NUM_REGS
- FP0_REGNUM
) * 8
2068 find_dummy_frame_regs (frame_info
, frame_saved_regs
);
2070 /* Interrupt handlers are special too. They lay out the register
2071 state in the exact same order as the register numbers in GDB. */
2072 if (pc_in_interrupt_handler (frame_info
->pc
))
2074 for (i
= 0; i
< NUM_REGS
; i
++)
2076 /* SP is a little special. */
2078 frame_saved_regs
->regs
[SP_REGNUM
]
2079 = read_memory_integer (frame_info
->frame
+ SP_REGNUM
* 4, 4);
2081 frame_saved_regs
->regs
[i
] = frame_info
->frame
+ i
* 4;
2086 /* Handle signal handler callers. */
2087 if (frame_info
->signal_handler_caller
)
2089 FRAME_FIND_SAVED_REGS_IN_SIGTRAMP (frame_info
, frame_saved_regs
);
2093 /* Get the starting address of the function referred to by the PC
2095 pc
= get_pc_function_start (frame_info
->pc
);
2098 u
= find_unwind_entry (pc
);
2102 /* This is how much of a frame adjustment we need to account for. */
2103 stack_remaining
= u
->Total_frame_size
<< 3;
2105 /* Magic register saves we want to know about. */
2106 save_rp
= u
->Save_RP
;
2107 save_sp
= u
->Save_SP
;
2109 /* Turn the Entry_GR field into a bitmask. */
2111 for (i
= 3; i
< u
->Entry_GR
+ 3; i
++)
2113 /* Frame pointer gets saved into a special location. */
2114 if (u
->Save_SP
&& i
== FP_REGNUM
)
2117 save_gr
|= (1 << i
);
2120 /* Turn the Entry_FR field into a bitmask too. */
2122 for (i
= 12; i
< u
->Entry_FR
+ 12; i
++)
2123 save_fr
|= (1 << i
);
2125 /* The frame always represents the value of %sp at entry to the
2126 current function (and is thus equivalent to the "saved" stack
2128 frame_saved_regs
->regs
[SP_REGNUM
] = frame_info
->frame
;
2130 /* Loop until we find everything of interest or hit a branch.
2132 For unoptimized GCC code and for any HP CC code this will never ever
2133 examine any user instructions.
2135 For optimzied GCC code we're faced with problems. GCC will schedule
2136 its prologue and make prologue instructions available for delay slot
2137 filling. The end result is user code gets mixed in with the prologue
2138 and a prologue instruction may be in the delay slot of the first branch
2141 Some unexpected things are expected with debugging optimized code, so
2142 we allow this routine to walk past user instructions in optimized
2144 while (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0)
2146 status
= target_read_memory (pc
, buf
, 4);
2147 inst
= extract_unsigned_integer (buf
, 4);
2153 /* Note the interesting effects of this instruction. */
2154 stack_remaining
-= prologue_inst_adjust_sp (inst
);
2156 /* There is only one instruction used for saving RP into the stack. */
2157 if (inst
== 0x6bc23fd9)
2160 frame_saved_regs
->regs
[RP_REGNUM
] = frame_info
->frame
- 20;
2163 /* Just note that we found the save of SP into the stack. The
2164 value for frame_saved_regs was computed above. */
2165 if ((inst
& 0xffffc000) == 0x6fc10000)
2168 /* Account for general and floating-point register saves. */
2169 reg
= inst_saves_gr (inst
);
2170 if (reg
>= 3 && reg
<= 18
2171 && (!u
->Save_SP
|| reg
!= FP_REGNUM
))
2173 save_gr
&= ~(1 << reg
);
2175 /* stwm with a positive displacement is a *post modify*. */
2176 if ((inst
>> 26) == 0x1b
2177 && extract_14 (inst
) >= 0)
2178 frame_saved_regs
->regs
[reg
] = frame_info
->frame
;
2181 /* Handle code with and without frame pointers. */
2183 frame_saved_regs
->regs
[reg
]
2184 = frame_info
->frame
+ extract_14 (inst
);
2186 frame_saved_regs
->regs
[reg
]
2187 = frame_info
->frame
+ (u
->Total_frame_size
<< 3)
2188 + extract_14 (inst
);
2193 /* GCC handles callee saved FP regs a little differently.
2195 It emits an instruction to put the value of the start of
2196 the FP store area into %r1. It then uses fstds,ma with
2197 a basereg of %r1 for the stores.
2199 HP CC emits them at the current stack pointer modifying
2200 the stack pointer as it stores each register. */
2202 /* ldo X(%r3),%r1 or ldo X(%r30),%r1. */
2203 if ((inst
& 0xffffc000) == 0x34610000
2204 || (inst
& 0xffffc000) == 0x37c10000)
2205 fp_loc
= extract_14 (inst
);
2207 reg
= inst_saves_fr (inst
);
2208 if (reg
>= 12 && reg
<= 21)
2210 /* Note +4 braindamage below is necessary because the FP status
2211 registers are internally 8 registers rather than the expected
2213 save_fr
&= ~(1 << reg
);
2216 /* 1st HP CC FP register store. After this instruction
2217 we've set enough state that the GCC and HPCC code are
2218 both handled in the same manner. */
2219 frame_saved_regs
->regs
[reg
+ FP4_REGNUM
+ 4] = frame_info
->frame
;
2224 frame_saved_regs
->regs
[reg
+ FP0_REGNUM
+ 4]
2225 = frame_info
->frame
+ fp_loc
;
2230 /* Quit if we hit any kind of branch. This can happen if a prologue
2231 instruction is in the delay slot of the first call/branch. */
2232 if (is_branch (inst
))
2240 #ifdef MAINTENANCE_CMDS
2243 unwind_command (exp
, from_tty
)
2251 struct unwind_table_entry
*u
;
2254 /* If we have an expression, evaluate it and use it as the address. */
2256 if (exp
!= 0 && *exp
!= 0)
2257 address
= parse_and_eval_address (exp
);
2261 xxx
.u
= find_unwind_entry (address
);
2265 printf_unfiltered ("Can't find unwind table entry for PC 0x%x\n", address
);
2269 printf_unfiltered ("%08x\n%08X\n%08X\n%08X\n", xxx
.foo
[0], xxx
.foo
[1], xxx
.foo
[2],
2272 #endif /* MAINTENANCE_CMDS */
2275 _initialize_hppa_tdep ()
2277 #ifdef MAINTENANCE_CMDS
2278 add_cmd ("unwind", class_maintenance
, unwind_command
,
2279 "Print unwind table entry at given address.",
2280 &maintenanceprintlist
);
2281 #endif /* MAINTENANCE_CMDS */