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
)
713 case PARAMETER_RELOCATION
:
724 frameless_function_invocation (frame
)
725 struct frame_info
*frame
;
727 struct unwind_table_entry
*u
;
729 u
= find_unwind_entry (frame
->pc
);
734 return (u
->Total_frame_size
== 0 && u
->stub_type
== 0);
738 saved_pc_after_call (frame
)
739 struct frame_info
*frame
;
743 struct unwind_table_entry
*u
;
745 ret_regnum
= find_return_regnum (get_frame_pc (frame
));
746 pc
= read_register (ret_regnum
) & ~0x3;
748 /* If PC is in a linker stub, then we need to dig the address
749 the stub will return to out of the stack. */
750 u
= find_unwind_entry (pc
);
751 if (u
&& u
->stub_type
!= 0)
752 return frame_saved_pc (frame
);
758 frame_saved_pc (frame
)
759 struct frame_info
*frame
;
761 CORE_ADDR pc
= get_frame_pc (frame
);
762 struct unwind_table_entry
*u
;
764 /* BSD, HPUX & OSF1 all lay out the hardware state in the same manner
765 at the base of the frame in an interrupt handler. Registers within
766 are saved in the exact same order as GDB numbers registers. How
768 if (pc_in_interrupt_handler (pc
))
769 return read_memory_integer (frame
->frame
+ PC_REGNUM
* 4, 4) & ~0x3;
771 /* Deal with signal handler caller frames too. */
772 if (frame
->signal_handler_caller
)
775 FRAME_SAVED_PC_IN_SIGTRAMP (frame
, &rp
);
779 if (frameless_function_invocation (frame
))
783 ret_regnum
= find_return_regnum (pc
);
785 /* If the next frame is an interrupt frame or a signal
786 handler caller, then we need to look in the saved
787 register area to get the return pointer (the values
788 in the registers may not correspond to anything useful). */
790 && (frame
->next
->signal_handler_caller
791 || pc_in_interrupt_handler (frame
->next
->pc
)))
793 struct frame_saved_regs saved_regs
;
795 get_frame_saved_regs (frame
->next
, &saved_regs
);
796 if (read_memory_integer (saved_regs
.regs
[FLAGS_REGNUM
], 4) & 0x2)
798 pc
= read_memory_integer (saved_regs
.regs
[31], 4) & ~0x3;
800 /* Syscalls are really two frames. The syscall stub itself
801 with a return pointer in %rp and the kernel call with
802 a return pointer in %r31. We return the %rp variant
803 if %r31 is the same as frame->pc. */
805 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
808 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
811 pc
= read_register (ret_regnum
) & ~0x3;
818 rp_offset
= rp_saved (pc
);
819 /* Similar to code in frameless function case. If the next
820 frame is a signal or interrupt handler, then dig the right
821 information out of the saved register info. */
824 && (frame
->next
->signal_handler_caller
825 || pc_in_interrupt_handler (frame
->next
->pc
)))
827 struct frame_saved_regs saved_regs
;
829 get_frame_saved_regs (frame
->next
, &saved_regs
);
830 if (read_memory_integer (saved_regs
.regs
[FLAGS_REGNUM
], 4) & 0x2)
832 pc
= read_memory_integer (saved_regs
.regs
[31], 4) & ~0x3;
834 /* Syscalls are really two frames. The syscall stub itself
835 with a return pointer in %rp and the kernel call with
836 a return pointer in %r31. We return the %rp variant
837 if %r31 is the same as frame->pc. */
839 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
842 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
844 else if (rp_offset
== 0)
845 pc
= read_register (RP_REGNUM
) & ~0x3;
847 pc
= read_memory_integer (frame
->frame
+ rp_offset
, 4) & ~0x3;
850 /* If PC is inside a linker stub, then dig out the address the stub
852 u
= find_unwind_entry (pc
);
853 if (u
&& u
->stub_type
!= 0)
859 /* We need to correct the PC and the FP for the outermost frame when we are
863 init_extra_frame_info (fromleaf
, frame
)
865 struct frame_info
*frame
;
870 if (frame
->next
&& !fromleaf
)
873 /* If the next frame represents a frameless function invocation
874 then we have to do some adjustments that are normally done by
875 FRAME_CHAIN. (FRAME_CHAIN is not called in this case.) */
878 /* Find the framesize of *this* frame without peeking at the PC
879 in the current frame structure (it isn't set yet). */
880 framesize
= find_proc_framesize (FRAME_SAVED_PC (get_next_frame (frame
)));
882 /* Now adjust our base frame accordingly. If we have a frame pointer
883 use it, else subtract the size of this frame from the current
884 frame. (we always want frame->frame to point at the lowest address
887 frame
->frame
= read_register (FP_REGNUM
);
889 frame
->frame
-= framesize
;
893 flags
= read_register (FLAGS_REGNUM
);
894 if (flags
& 2) /* In system call? */
895 frame
->pc
= read_register (31) & ~0x3;
897 /* The outermost frame is always derived from PC-framesize
899 One might think frameless innermost frames should have
900 a frame->frame that is the same as the parent's frame->frame.
901 That is wrong; frame->frame in that case should be the *high*
902 address of the parent's frame. It's complicated as hell to
903 explain, but the parent *always* creates some stack space for
904 the child. So the child actually does have a frame of some
905 sorts, and its base is the high address in its parent's frame. */
906 framesize
= find_proc_framesize(frame
->pc
);
908 frame
->frame
= read_register (FP_REGNUM
);
910 frame
->frame
= read_register (SP_REGNUM
) - framesize
;
913 /* Given a GDB frame, determine the address of the calling function's frame.
914 This will be used to create a new GDB frame struct, and then
915 INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame.
917 This may involve searching through prologues for several functions
918 at boundaries where GCC calls HP C code, or where code which has
919 a frame pointer calls code without a frame pointer. */
923 struct frame_info
*frame
;
925 int my_framesize
, caller_framesize
;
926 struct unwind_table_entry
*u
;
927 CORE_ADDR frame_base
;
929 /* Handle HPUX, BSD, and OSF1 style interrupt frames first. These
930 are easy; at *sp we have a full save state strucutre which we can
931 pull the old stack pointer from. Also see frame_saved_pc for
932 code to dig a saved PC out of the save state structure. */
933 if (pc_in_interrupt_handler (frame
->pc
))
934 frame_base
= read_memory_integer (frame
->frame
+ SP_REGNUM
* 4, 4);
935 else if (frame
->signal_handler_caller
)
937 FRAME_BASE_BEFORE_SIGTRAMP (frame
, &frame_base
);
940 frame_base
= frame
->frame
;
942 /* Get frame sizes for the current frame and the frame of the
944 my_framesize
= find_proc_framesize (frame
->pc
);
945 caller_framesize
= find_proc_framesize (FRAME_SAVED_PC(frame
));
947 /* If caller does not have a frame pointer, then its frame
948 can be found at current_frame - caller_framesize. */
949 if (caller_framesize
!= -1)
950 return frame_base
- caller_framesize
;
952 /* Both caller and callee have frame pointers and are GCC compiled
953 (SAVE_SP bit in unwind descriptor is on for both functions.
954 The previous frame pointer is found at the top of the current frame. */
955 if (caller_framesize
== -1 && my_framesize
== -1)
956 return read_memory_integer (frame_base
, 4);
958 /* Caller has a frame pointer, but callee does not. This is a little
959 more difficult as GCC and HP C lay out locals and callee register save
960 areas very differently.
962 The previous frame pointer could be in a register, or in one of
963 several areas on the stack.
965 Walk from the current frame to the innermost frame examining
966 unwind descriptors to determine if %r3 ever gets saved into the
967 stack. If so return whatever value got saved into the stack.
968 If it was never saved in the stack, then the value in %r3 is still
971 We use information from unwind descriptors to determine if %r3
972 is saved into the stack (Entry_GR field has this information). */
976 u
= find_unwind_entry (frame
->pc
);
980 /* We could find this information by examining prologues. I don't
981 think anyone has actually written any tools (not even "strip")
982 which leave them out of an executable, so maybe this is a moot
984 warning ("Unable to find unwind for PC 0x%x -- Help!", frame
->pc
);
988 /* Entry_GR specifies the number of callee-saved general registers
989 saved in the stack. It starts at %r3, so %r3 would be 1. */
990 if (u
->Entry_GR
>= 1 || u
->Save_SP
991 || frame
->signal_handler_caller
992 || pc_in_interrupt_handler (frame
->pc
))
1000 /* We may have walked down the chain into a function with a frame
1003 && !frame
->signal_handler_caller
1004 && !pc_in_interrupt_handler (frame
->pc
))
1005 return read_memory_integer (frame
->frame
, 4);
1006 /* %r3 was saved somewhere in the stack. Dig it out. */
1009 struct frame_saved_regs saved_regs
;
1011 get_frame_saved_regs (frame
, &saved_regs
);
1012 return read_memory_integer (saved_regs
.regs
[FP_REGNUM
], 4);
1017 /* The value in %r3 was never saved into the stack (thus %r3 still
1018 holds the value of the previous frame pointer). */
1019 return read_register (FP_REGNUM
);
1024 /* To see if a frame chain is valid, see if the caller looks like it
1025 was compiled with gcc. */
1028 frame_chain_valid (chain
, thisframe
)
1030 struct frame_info
*thisframe
;
1032 struct minimal_symbol
*msym_us
;
1033 struct minimal_symbol
*msym_start
;
1034 struct unwind_table_entry
*u
, *next_u
= NULL
;
1035 struct frame_info
*next
;
1040 u
= find_unwind_entry (thisframe
->pc
);
1045 /* We can't just check that the same of msym_us is "_start", because
1046 someone idiotically decided that they were going to make a Ltext_end
1047 symbol with the same address. This Ltext_end symbol is totally
1048 indistinguishable (as nearly as I can tell) from the symbol for a function
1049 which is (legitimately, since it is in the user's namespace)
1050 named Ltext_end, so we can't just ignore it. */
1051 msym_us
= lookup_minimal_symbol_by_pc (FRAME_SAVED_PC (thisframe
));
1052 msym_start
= lookup_minimal_symbol ("_start", NULL
);
1055 && SYMBOL_VALUE_ADDRESS (msym_us
) == SYMBOL_VALUE_ADDRESS (msym_start
))
1058 next
= get_next_frame (thisframe
);
1060 next_u
= find_unwind_entry (next
->pc
);
1062 /* If this frame does not save SP, has no stack, isn't a stub,
1063 and doesn't "call" an interrupt routine or signal handler caller,
1064 then its not valid. */
1065 if (u
->Save_SP
|| u
->Total_frame_size
|| u
->stub_type
!= 0
1066 || (thisframe
->next
&& thisframe
->next
->signal_handler_caller
)
1067 || (next_u
&& next_u
->HP_UX_interrupt_marker
))
1070 if (pc_in_linker_stub (thisframe
->pc
))
1077 * These functions deal with saving and restoring register state
1078 * around a function call in the inferior. They keep the stack
1079 * double-word aligned; eventually, on an hp700, the stack will have
1080 * to be aligned to a 64-byte boundary.
1086 register CORE_ADDR sp
;
1087 register int regnum
;
1091 /* Space for "arguments"; the RP goes in here. */
1092 sp
= read_register (SP_REGNUM
) + 48;
1093 int_buffer
= read_register (RP_REGNUM
) | 0x3;
1094 write_memory (sp
- 20, (char *)&int_buffer
, 4);
1096 int_buffer
= read_register (FP_REGNUM
);
1097 write_memory (sp
, (char *)&int_buffer
, 4);
1099 write_register (FP_REGNUM
, sp
);
1103 for (regnum
= 1; regnum
< 32; regnum
++)
1104 if (regnum
!= RP_REGNUM
&& regnum
!= FP_REGNUM
)
1105 sp
= push_word (sp
, read_register (regnum
));
1109 for (regnum
= FP0_REGNUM
; regnum
< NUM_REGS
; regnum
++)
1111 read_register_bytes (REGISTER_BYTE (regnum
), (char *)&freg_buffer
, 8);
1112 sp
= push_bytes (sp
, (char *)&freg_buffer
, 8);
1114 sp
= push_word (sp
, read_register (IPSW_REGNUM
));
1115 sp
= push_word (sp
, read_register (SAR_REGNUM
));
1116 sp
= push_word (sp
, read_register (PCOQ_HEAD_REGNUM
));
1117 sp
= push_word (sp
, read_register (PCSQ_HEAD_REGNUM
));
1118 sp
= push_word (sp
, read_register (PCOQ_TAIL_REGNUM
));
1119 sp
= push_word (sp
, read_register (PCSQ_TAIL_REGNUM
));
1120 write_register (SP_REGNUM
, sp
);
1123 find_dummy_frame_regs (frame
, frame_saved_regs
)
1124 struct frame_info
*frame
;
1125 struct frame_saved_regs
*frame_saved_regs
;
1127 CORE_ADDR fp
= frame
->frame
;
1130 frame_saved_regs
->regs
[RP_REGNUM
] = fp
- 20 & ~0x3;
1131 frame_saved_regs
->regs
[FP_REGNUM
] = fp
;
1132 frame_saved_regs
->regs
[1] = fp
+ 8;
1134 for (fp
+= 12, i
= 3; i
< 32; i
++)
1138 frame_saved_regs
->regs
[i
] = fp
;
1144 for (i
= FP0_REGNUM
; i
< NUM_REGS
; i
++, fp
+= 8)
1145 frame_saved_regs
->regs
[i
] = fp
;
1147 frame_saved_regs
->regs
[IPSW_REGNUM
] = fp
;
1148 frame_saved_regs
->regs
[SAR_REGNUM
] = fp
+ 4;
1149 frame_saved_regs
->regs
[PCOQ_HEAD_REGNUM
] = fp
+ 8;
1150 frame_saved_regs
->regs
[PCSQ_HEAD_REGNUM
] = fp
+ 12;
1151 frame_saved_regs
->regs
[PCOQ_TAIL_REGNUM
] = fp
+ 16;
1152 frame_saved_regs
->regs
[PCSQ_TAIL_REGNUM
] = fp
+ 20;
1158 register struct frame_info
*frame
= get_current_frame ();
1159 register CORE_ADDR fp
;
1160 register int regnum
;
1161 struct frame_saved_regs fsr
;
1164 fp
= FRAME_FP (frame
);
1165 get_frame_saved_regs (frame
, &fsr
);
1167 #ifndef NO_PC_SPACE_QUEUE_RESTORE
1168 if (fsr
.regs
[IPSW_REGNUM
]) /* Restoring a call dummy frame */
1169 restore_pc_queue (&fsr
);
1172 for (regnum
= 31; regnum
> 0; regnum
--)
1173 if (fsr
.regs
[regnum
])
1174 write_register (regnum
, read_memory_integer (fsr
.regs
[regnum
], 4));
1176 for (regnum
= NUM_REGS
- 1; regnum
>= FP0_REGNUM
; regnum
--)
1177 if (fsr
.regs
[regnum
])
1179 read_memory (fsr
.regs
[regnum
], (char *)&freg_buffer
, 8);
1180 write_register_bytes (REGISTER_BYTE (regnum
), (char *)&freg_buffer
, 8);
1183 if (fsr
.regs
[IPSW_REGNUM
])
1184 write_register (IPSW_REGNUM
,
1185 read_memory_integer (fsr
.regs
[IPSW_REGNUM
], 4));
1187 if (fsr
.regs
[SAR_REGNUM
])
1188 write_register (SAR_REGNUM
,
1189 read_memory_integer (fsr
.regs
[SAR_REGNUM
], 4));
1191 /* If the PC was explicitly saved, then just restore it. */
1192 if (fsr
.regs
[PCOQ_TAIL_REGNUM
])
1193 write_register (PCOQ_TAIL_REGNUM
,
1194 read_memory_integer (fsr
.regs
[PCOQ_TAIL_REGNUM
], 4));
1196 /* Else use the value in %rp to set the new PC. */
1198 target_write_pc (read_register (RP_REGNUM
), 0);
1200 write_register (FP_REGNUM
, read_memory_integer (fp
, 4));
1202 if (fsr
.regs
[IPSW_REGNUM
]) /* call dummy */
1203 write_register (SP_REGNUM
, fp
- 48);
1205 write_register (SP_REGNUM
, fp
);
1207 flush_cached_frames ();
1211 * After returning to a dummy on the stack, restore the instruction
1212 * queue space registers. */
1215 restore_pc_queue (fsr
)
1216 struct frame_saved_regs
*fsr
;
1218 CORE_ADDR pc
= read_pc ();
1219 CORE_ADDR new_pc
= read_memory_integer (fsr
->regs
[PCOQ_HEAD_REGNUM
], 4);
1221 struct target_waitstatus w
;
1224 /* Advance past break instruction in the call dummy. */
1225 write_register (PCOQ_HEAD_REGNUM
, pc
+ 4);
1226 write_register (PCOQ_TAIL_REGNUM
, pc
+ 8);
1229 * HPUX doesn't let us set the space registers or the space
1230 * registers of the PC queue through ptrace. Boo, hiss.
1231 * Conveniently, the call dummy has this sequence of instructions
1236 * So, load up the registers and single step until we are in the
1240 write_register (21, read_memory_integer (fsr
->regs
[PCSQ_HEAD_REGNUM
], 4));
1241 write_register (22, new_pc
);
1243 for (insn_count
= 0; insn_count
< 3; insn_count
++)
1245 /* FIXME: What if the inferior gets a signal right now? Want to
1246 merge this into wait_for_inferior (as a special kind of
1247 watchpoint? By setting a breakpoint at the end? Is there
1248 any other choice? Is there *any* way to do this stuff with
1249 ptrace() or some equivalent?). */
1251 target_wait (inferior_pid
, &w
);
1253 if (w
.kind
== TARGET_WAITKIND_SIGNALLED
)
1255 stop_signal
= w
.value
.sig
;
1256 terminal_ours_for_output ();
1257 printf_unfiltered ("\nProgram terminated with signal %s, %s.\n",
1258 target_signal_to_name (stop_signal
),
1259 target_signal_to_string (stop_signal
));
1260 gdb_flush (gdb_stdout
);
1264 target_terminal_ours ();
1265 target_fetch_registers (-1);
1270 hppa_push_arguments (nargs
, args
, sp
, struct_return
, struct_addr
)
1275 CORE_ADDR struct_addr
;
1277 /* array of arguments' offsets */
1278 int *offset
= (int *)alloca(nargs
* sizeof (int));
1282 for (i
= 0; i
< nargs
; i
++)
1284 /* Coerce chars to int & float to double if necessary */
1285 args
[i
] = value_arg_coerce (args
[i
]);
1287 cum
+= TYPE_LENGTH (VALUE_TYPE (args
[i
]));
1289 /* value must go at proper alignment. Assume alignment is a
1291 alignment
= hppa_alignof (VALUE_TYPE (args
[i
]));
1292 if (cum
% alignment
)
1293 cum
= (cum
+ alignment
) & -alignment
;
1296 sp
+= max ((cum
+ 7) & -8, 16);
1298 for (i
= 0; i
< nargs
; i
++)
1299 write_memory (sp
+ offset
[i
], VALUE_CONTENTS (args
[i
]),
1300 TYPE_LENGTH (VALUE_TYPE (args
[i
])));
1303 write_register (28, struct_addr
);
1308 * Insert the specified number of args and function address
1309 * into a call sequence of the above form stored at DUMMYNAME.
1311 * On the hppa we need to call the stack dummy through $$dyncall.
1312 * Therefore our version of FIX_CALL_DUMMY takes an extra argument,
1313 * real_pc, which is the location where gdb should start up the
1314 * inferior to do the function call.
1318 hppa_fix_call_dummy (dummy
, pc
, fun
, nargs
, args
, type
, gcc_p
)
1327 CORE_ADDR dyncall_addr
, sr4export_addr
;
1328 struct minimal_symbol
*msymbol
;
1329 int flags
= read_register (FLAGS_REGNUM
);
1330 struct unwind_table_entry
*u
;
1332 msymbol
= lookup_minimal_symbol ("$$dyncall", (struct objfile
*) NULL
);
1333 if (msymbol
== NULL
)
1334 error ("Can't find an address for $$dyncall trampoline");
1336 dyncall_addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
1338 /* FUN could be a procedure label, in which case we have to get
1339 its real address and the value of its GOT/DP. */
1342 /* Get the GOT/DP value for the target function. It's
1343 at *(fun+4). Note the call dummy is *NOT* allowed to
1344 trash %r19 before calling the target function. */
1345 write_register (19, read_memory_integer ((fun
& ~0x3) + 4, 4));
1347 /* Now get the real address for the function we are calling, it's
1349 fun
= (CORE_ADDR
) read_memory_integer (fun
& ~0x3, 4);
1352 /* If we are calling an import stub (eg calling into a dynamic library)
1353 then have sr4export call the magic __d_plt_call routine which is linked
1354 in from end.o. (You can't use _sr4export to call the import stub as
1355 the value in sp-24 will get fried and you end up returning to the
1356 wrong location. You can't call the import stub directly as the code
1357 to bind the PLT entry to a function can't return to a stack address.) */
1358 u
= find_unwind_entry (fun
);
1359 if (u
&& u
->stub_type
== IMPORT
)
1362 msymbol
= lookup_minimal_symbol ("__d_plt_call", (struct objfile
*) NULL
);
1363 if (msymbol
== NULL
)
1364 error ("Can't find an address for __d_plt_call trampoline");
1366 /* This is where sr4export will jump to. */
1367 new_fun
= SYMBOL_VALUE_ADDRESS (msymbol
);
1369 /* We have to store the address of the stub in __shlib_funcptr. */
1370 msymbol
= lookup_minimal_symbol ("__shlib_funcptr",
1371 (struct objfile
*)NULL
);
1372 if (msymbol
== NULL
)
1373 error ("Can't find an address for __shlib_funcptr");
1375 target_write_memory (SYMBOL_VALUE_ADDRESS (msymbol
), (char *)&fun
, 4);
1380 /* We still need sr4export's address too. */
1381 msymbol
= lookup_minimal_symbol ("_sr4export", (struct objfile
*) NULL
);
1382 if (msymbol
== NULL
)
1383 error ("Can't find an address for _sr4export trampoline");
1385 sr4export_addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
1387 store_unsigned_integer
1388 (&dummy
[9*REGISTER_SIZE
],
1390 deposit_21 (fun
>> 11,
1391 extract_unsigned_integer (&dummy
[9*REGISTER_SIZE
],
1393 store_unsigned_integer
1394 (&dummy
[10*REGISTER_SIZE
],
1396 deposit_14 (fun
& MASK_11
,
1397 extract_unsigned_integer (&dummy
[10*REGISTER_SIZE
],
1399 store_unsigned_integer
1400 (&dummy
[12*REGISTER_SIZE
],
1402 deposit_21 (sr4export_addr
>> 11,
1403 extract_unsigned_integer (&dummy
[12*REGISTER_SIZE
],
1405 store_unsigned_integer
1406 (&dummy
[13*REGISTER_SIZE
],
1408 deposit_14 (sr4export_addr
& MASK_11
,
1409 extract_unsigned_integer (&dummy
[13*REGISTER_SIZE
],
1412 write_register (22, pc
);
1414 /* If we are in a syscall, then we should call the stack dummy
1415 directly. $$dyncall is not needed as the kernel sets up the
1416 space id registers properly based on the value in %r31. In
1417 fact calling $$dyncall will not work because the value in %r22
1418 will be clobbered on the syscall exit path. */
1422 return dyncall_addr
;
1426 /* Get the PC from %r31 if currently in a syscall. Also mask out privilege
1430 target_read_pc (pid
)
1433 int flags
= read_register (FLAGS_REGNUM
);
1436 return read_register (31) & ~0x3;
1437 return read_register (PC_REGNUM
) & ~0x3;
1440 /* Write out the PC. If currently in a syscall, then also write the new
1441 PC value into %r31. */
1444 target_write_pc (v
, pid
)
1448 int flags
= read_register (FLAGS_REGNUM
);
1450 /* If in a syscall, then set %r31. Also make sure to get the
1451 privilege bits set correctly. */
1453 write_register (31, (long) (v
| 0x3));
1455 write_register (PC_REGNUM
, (long) v
);
1456 write_register (NPC_REGNUM
, (long) v
+ 4);
1459 /* return the alignment of a type in bytes. Structures have the maximum
1460 alignment required by their fields. */
1466 int max_align
, align
, i
;
1467 switch (TYPE_CODE (arg
))
1472 return TYPE_LENGTH (arg
);
1473 case TYPE_CODE_ARRAY
:
1474 return hppa_alignof (TYPE_FIELD_TYPE (arg
, 0));
1475 case TYPE_CODE_STRUCT
:
1476 case TYPE_CODE_UNION
:
1478 for (i
= 0; i
< TYPE_NFIELDS (arg
); i
++)
1480 /* Bit fields have no real alignment. */
1481 if (!TYPE_FIELD_BITPOS (arg
, i
))
1483 align
= hppa_alignof (TYPE_FIELD_TYPE (arg
, i
));
1484 max_align
= max (max_align
, align
);
1493 /* Print the register regnum, or all registers if regnum is -1 */
1495 pa_do_registers_info (regnum
, fpregs
)
1499 char raw_regs
[REGISTER_BYTES
];
1502 for (i
= 0; i
< NUM_REGS
; i
++)
1503 read_relative_register_raw_bytes (i
, raw_regs
+ REGISTER_BYTE (i
));
1505 pa_print_registers (raw_regs
, regnum
, fpregs
);
1506 else if (regnum
< FP0_REGNUM
)
1507 printf_unfiltered ("%s %x\n", reg_names
[regnum
], *(long *)(raw_regs
+
1508 REGISTER_BYTE (regnum
)));
1510 pa_print_fp_reg (regnum
);
1513 pa_print_registers (raw_regs
, regnum
, fpregs
)
1520 for (i
= 0; i
< 18; i
++)
1521 printf_unfiltered ("%8.8s: %8x %8.8s: %8x %8.8s: %8x %8.8s: %8x\n",
1523 *(int *)(raw_regs
+ REGISTER_BYTE (i
)),
1525 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 18)),
1527 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 36)),
1529 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 54)));
1532 for (i
= 72; i
< NUM_REGS
; i
++)
1533 pa_print_fp_reg (i
);
1539 unsigned char raw_buffer
[MAX_REGISTER_RAW_SIZE
];
1540 unsigned char virtual_buffer
[MAX_REGISTER_VIRTUAL_SIZE
];
1542 /* Get 32bits of data. */
1543 read_relative_register_raw_bytes (i
, raw_buffer
);
1545 /* Put it in the buffer. No conversions are ever necessary. */
1546 memcpy (virtual_buffer
, raw_buffer
, REGISTER_RAW_SIZE (i
));
1548 fputs_filtered (reg_names
[i
], gdb_stdout
);
1549 print_spaces_filtered (8 - strlen (reg_names
[i
]), gdb_stdout
);
1550 fputs_filtered ("(single precision) ", gdb_stdout
);
1552 val_print (REGISTER_VIRTUAL_TYPE (i
), virtual_buffer
, 0, gdb_stdout
, 0,
1553 1, 0, Val_pretty_default
);
1554 printf_filtered ("\n");
1556 /* If "i" is even, then this register can also be a double-precision
1557 FP register. Dump it out as such. */
1560 /* Get the data in raw format for the 2nd half. */
1561 read_relative_register_raw_bytes (i
+ 1, raw_buffer
);
1563 /* Copy it into the appropriate part of the virtual buffer. */
1564 memcpy (virtual_buffer
+ REGISTER_RAW_SIZE (i
), raw_buffer
,
1565 REGISTER_RAW_SIZE (i
));
1567 /* Dump it as a double. */
1568 fputs_filtered (reg_names
[i
], gdb_stdout
);
1569 print_spaces_filtered (8 - strlen (reg_names
[i
]), gdb_stdout
);
1570 fputs_filtered ("(double precision) ", gdb_stdout
);
1572 val_print (builtin_type_double
, virtual_buffer
, 0, gdb_stdout
, 0,
1573 1, 0, Val_pretty_default
);
1574 printf_filtered ("\n");
1578 /* Figure out if PC is in a trampoline, and if so find out where
1579 the trampoline will jump to. If not in a trampoline, return zero.
1581 Simple code examination probably is not a good idea since the code
1582 sequences in trampolines can also appear in user code.
1584 We use unwinds and information from the minimal symbol table to
1585 determine when we're in a trampoline. This won't work for ELF
1586 (yet) since it doesn't create stub unwind entries. Whether or
1587 not ELF will create stub unwinds or normal unwinds for linker
1588 stubs is still being debated.
1590 This should handle simple calls through dyncall or sr4export,
1591 long calls, argument relocation stubs, and dyncall/sr4export
1592 calling an argument relocation stub. It even handles some stubs
1593 used in dynamic executables. */
1596 skip_trampoline_code (pc
, name
)
1601 long prev_inst
, curr_inst
, loc
;
1602 static CORE_ADDR dyncall
= 0;
1603 static CORE_ADDR sr4export
= 0;
1604 struct minimal_symbol
*msym
;
1605 struct unwind_table_entry
*u
;
1607 /* FIXME XXX - dyncall and sr4export must be initialized whenever we get a
1612 msym
= lookup_minimal_symbol ("$$dyncall", NULL
);
1614 dyncall
= SYMBOL_VALUE_ADDRESS (msym
);
1621 msym
= lookup_minimal_symbol ("_sr4export", NULL
);
1623 sr4export
= SYMBOL_VALUE_ADDRESS (msym
);
1628 /* Addresses passed to dyncall may *NOT* be the actual address
1629 of the function. So we may have to do something special. */
1632 pc
= (CORE_ADDR
) read_register (22);
1634 /* If bit 30 (counting from the left) is on, then pc is the address of
1635 the PLT entry for this function, not the address of the function
1636 itself. Bit 31 has meaning too, but only for MPE. */
1638 pc
= (CORE_ADDR
) read_memory_integer (pc
& ~0x3, 4);
1640 else if (pc
== sr4export
)
1641 pc
= (CORE_ADDR
) (read_register (22));
1643 /* Get the unwind descriptor corresponding to PC, return zero
1644 if no unwind was found. */
1645 u
= find_unwind_entry (pc
);
1649 /* If this isn't a linker stub, then return now. */
1650 if (u
->stub_type
== 0)
1651 return orig_pc
== pc
? 0 : pc
& ~0x3;
1653 /* It's a stub. Search for a branch and figure out where it goes.
1654 Note we have to handle multi insn branch sequences like ldil;ble.
1655 Most (all?) other branches can be determined by examining the contents
1656 of certain registers and the stack. */
1662 /* Make sure we haven't walked outside the range of this stub. */
1663 if (u
!= find_unwind_entry (loc
))
1665 warning ("Unable to find branch in linker stub");
1666 return orig_pc
== pc
? 0 : pc
& ~0x3;
1669 prev_inst
= curr_inst
;
1670 curr_inst
= read_memory_integer (loc
, 4);
1672 /* Does it look like a branch external using %r1? Then it's the
1673 branch from the stub to the actual function. */
1674 if ((curr_inst
& 0xffe0e000) == 0xe0202000)
1676 /* Yup. See if the previous instruction loaded
1677 a value into %r1. If so compute and return the jump address. */
1678 if ((prev_inst
& 0xffe00000) == 0x20200000)
1679 return (extract_21 (prev_inst
) + extract_17 (curr_inst
)) & ~0x3;
1682 warning ("Unable to find ldil X,%%r1 before ble Y(%%sr4,%%r1).");
1683 return orig_pc
== pc
? 0 : pc
& ~0x3;
1687 /* Does it look like bl X,%rp or bl X,%r0? Another way to do a
1688 branch from the stub to the actual function. */
1689 else if ((curr_inst
& 0xffe0e000) == 0xe8400000
1690 || (curr_inst
& 0xffe0e000) == 0xe8000000)
1691 return (loc
+ extract_17 (curr_inst
) + 8) & ~0x3;
1693 /* Does it look like bv (rp)? Note this depends on the
1694 current stack pointer being the same as the stack
1695 pointer in the stub itself! This is a branch on from the
1696 stub back to the original caller. */
1697 else if ((curr_inst
& 0xffe0e000) == 0xe840c000)
1699 /* Yup. See if the previous instruction loaded
1701 if (prev_inst
== 0x4bc23ff1)
1702 return (read_memory_integer
1703 (read_register (SP_REGNUM
) - 8, 4)) & ~0x3;
1706 warning ("Unable to find restore of %%rp before bv (%%rp).");
1707 return orig_pc
== pc
? 0 : pc
& ~0x3;
1711 /* What about be,n 0(sr0,%rp)? It's just another way we return to
1712 the original caller from the stub. Used in dynamic executables. */
1713 else if (curr_inst
== 0xe0400002)
1715 /* The value we jump to is sitting in sp - 24. But that's
1716 loaded several instructions before the be instruction.
1717 I guess we could check for the previous instruction being
1718 mtsp %r1,%sr0 if we want to do sanity checking. */
1719 return (read_memory_integer
1720 (read_register (SP_REGNUM
) - 24, 4)) & ~0x3;
1723 /* Haven't found the branch yet, but we're still in the stub.
1729 /* For the given instruction (INST), return any adjustment it makes
1730 to the stack pointer or zero for no adjustment.
1732 This only handles instructions commonly found in prologues. */
1735 prologue_inst_adjust_sp (inst
)
1738 /* This must persist across calls. */
1739 static int save_high21
;
1741 /* The most common way to perform a stack adjustment ldo X(sp),sp */
1742 if ((inst
& 0xffffc000) == 0x37de0000)
1743 return extract_14 (inst
);
1746 if ((inst
& 0xffe00000) == 0x6fc00000)
1747 return extract_14 (inst
);
1749 /* addil high21,%r1; ldo low11,(%r1),%r30)
1750 save high bits in save_high21 for later use. */
1751 if ((inst
& 0xffe00000) == 0x28200000)
1753 save_high21
= extract_21 (inst
);
1757 if ((inst
& 0xffff0000) == 0x343e0000)
1758 return save_high21
+ extract_14 (inst
);
1760 /* fstws as used by the HP compilers. */
1761 if ((inst
& 0xffffffe0) == 0x2fd01220)
1762 return extract_5_load (inst
);
1764 /* No adjustment. */
1768 /* Return nonzero if INST is a branch of some kind, else return zero. */
1798 /* Return the register number for a GR which is saved by INST or
1799 zero it INST does not save a GR. */
1802 inst_saves_gr (inst
)
1805 /* Does it look like a stw? */
1806 if ((inst
>> 26) == 0x1a)
1807 return extract_5R_store (inst
);
1809 /* Does it look like a stwm? GCC & HPC may use this in prologues. */
1810 if ((inst
>> 26) == 0x1b)
1811 return extract_5R_store (inst
);
1813 /* Does it look like sth or stb? HPC versions 9.0 and later use these
1815 if ((inst
>> 26) == 0x19 || (inst
>> 26) == 0x18)
1816 return extract_5R_store (inst
);
1821 /* Return the register number for a FR which is saved by INST or
1822 zero it INST does not save a FR.
1824 Note we only care about full 64bit register stores (that's the only
1825 kind of stores the prologue will use).
1827 FIXME: What about argument stores with the HP compiler in ANSI mode? */
1830 inst_saves_fr (inst
)
1833 if ((inst
& 0xfc00dfc0) == 0x2c001200)
1834 return extract_5r_store (inst
);
1838 /* Advance PC across any function entry prologue instructions
1839 to reach some "real" code.
1841 Use information in the unwind table to determine what exactly should
1842 be in the prologue. */
1849 unsigned long inst
, stack_remaining
, save_gr
, save_fr
, save_rp
, save_sp
;
1850 unsigned long args_stored
, status
, i
;
1851 struct unwind_table_entry
*u
;
1853 u
= find_unwind_entry (pc
);
1857 /* If we are not at the beginning of a function, then return now. */
1858 if ((pc
& ~0x3) != u
->region_start
)
1861 /* This is how much of a frame adjustment we need to account for. */
1862 stack_remaining
= u
->Total_frame_size
<< 3;
1864 /* Magic register saves we want to know about. */
1865 save_rp
= u
->Save_RP
;
1866 save_sp
= u
->Save_SP
;
1868 /* An indication that args may be stored into the stack. Unfortunately
1869 the HPUX compilers tend to set this in cases where no args were
1871 args_stored
= u
->Args_stored
;
1873 /* Turn the Entry_GR field into a bitmask. */
1875 for (i
= 3; i
< u
->Entry_GR
+ 3; i
++)
1877 /* Frame pointer gets saved into a special location. */
1878 if (u
->Save_SP
&& i
== FP_REGNUM
)
1881 save_gr
|= (1 << i
);
1884 /* Turn the Entry_FR field into a bitmask too. */
1886 for (i
= 12; i
< u
->Entry_FR
+ 12; i
++)
1887 save_fr
|= (1 << i
);
1889 /* Loop until we find everything of interest or hit a branch.
1891 For unoptimized GCC code and for any HP CC code this will never ever
1892 examine any user instructions.
1894 For optimzied GCC code we're faced with problems. GCC will schedule
1895 its prologue and make prologue instructions available for delay slot
1896 filling. The end result is user code gets mixed in with the prologue
1897 and a prologue instruction may be in the delay slot of the first branch
1900 Some unexpected things are expected with debugging optimized code, so
1901 we allow this routine to walk past user instructions in optimized
1903 while (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0
1906 unsigned int reg_num
;
1907 unsigned long old_stack_remaining
, old_save_gr
, old_save_fr
;
1908 unsigned long old_save_rp
, old_save_sp
, old_args_stored
, next_inst
;
1910 /* Save copies of all the triggers so we can compare them later
1912 old_save_gr
= save_gr
;
1913 old_save_fr
= save_fr
;
1914 old_save_rp
= save_rp
;
1915 old_save_sp
= save_sp
;
1916 old_stack_remaining
= stack_remaining
;
1918 status
= target_read_memory (pc
, buf
, 4);
1919 inst
= extract_unsigned_integer (buf
, 4);
1925 /* Note the interesting effects of this instruction. */
1926 stack_remaining
-= prologue_inst_adjust_sp (inst
);
1928 /* There is only one instruction used for saving RP into the stack. */
1929 if (inst
== 0x6bc23fd9)
1932 /* This is the only way we save SP into the stack. At this time
1933 the HP compilers never bother to save SP into the stack. */
1934 if ((inst
& 0xffffc000) == 0x6fc10000)
1937 /* Account for general and floating-point register saves. */
1938 reg_num
= inst_saves_gr (inst
);
1939 save_gr
&= ~(1 << reg_num
);
1941 /* Ugh. Also account for argument stores into the stack.
1942 Unfortunately args_stored only tells us that some arguments
1943 where stored into the stack. Not how many or what kind!
1945 This is a kludge as on the HP compiler sets this bit and it
1946 never does prologue scheduling. So once we see one, skip past
1947 all of them. We have similar code for the fp arg stores below.
1949 FIXME. Can still die if we have a mix of GR and FR argument
1951 if (reg_num
>= 23 && reg_num
<= 26)
1953 while (reg_num
>= 23 && reg_num
<= 26)
1956 status
= target_read_memory (pc
, buf
, 4);
1957 inst
= extract_unsigned_integer (buf
, 4);
1960 reg_num
= inst_saves_gr (inst
);
1966 reg_num
= inst_saves_fr (inst
);
1967 save_fr
&= ~(1 << reg_num
);
1969 status
= target_read_memory (pc
+ 4, buf
, 4);
1970 next_inst
= extract_unsigned_integer (buf
, 4);
1976 /* We've got to be read to handle the ldo before the fp register
1978 if ((inst
& 0xfc000000) == 0x34000000
1979 && inst_saves_fr (next_inst
) >= 4
1980 && inst_saves_fr (next_inst
) <= 7)
1982 /* So we drop into the code below in a reasonable state. */
1983 reg_num
= inst_saves_fr (next_inst
);
1987 /* Ugh. Also account for argument stores into the stack.
1988 This is a kludge as on the HP compiler sets this bit and it
1989 never does prologue scheduling. So once we see one, skip past
1991 if (reg_num
>= 4 && reg_num
<= 7)
1993 while (reg_num
>= 4 && reg_num
<= 7)
1996 status
= target_read_memory (pc
, buf
, 4);
1997 inst
= extract_unsigned_integer (buf
, 4);
2000 if ((inst
& 0xfc000000) != 0x34000000)
2002 status
= target_read_memory (pc
+ 4, buf
, 4);
2003 next_inst
= extract_unsigned_integer (buf
, 4);
2006 reg_num
= inst_saves_fr (next_inst
);
2012 /* Quit if we hit any kind of branch. This can happen if a prologue
2013 instruction is in the delay slot of the first call/branch. */
2014 if (is_branch (inst
))
2017 /* What a crock. The HP compilers set args_stored even if no
2018 arguments were stored into the stack (boo hiss). This could
2019 cause this code to then skip a bunch of user insns (up to the
2022 To combat this we try to identify when args_stored was bogusly
2023 set and clear it. We only do this when args_stored is nonzero,
2024 all other resources are accounted for, and nothing changed on
2027 && ! (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0)
2028 && old_save_gr
== save_gr
&& old_save_fr
== save_fr
2029 && old_save_rp
== save_rp
&& old_save_sp
== save_sp
2030 && old_stack_remaining
== stack_remaining
)
2040 /* Put here the code to store, into a struct frame_saved_regs,
2041 the addresses of the saved registers of frame described by FRAME_INFO.
2042 This includes special registers such as pc and fp saved in special
2043 ways in the stack frame. sp is even more special:
2044 the address we return for it IS the sp for the next frame. */
2047 hppa_frame_find_saved_regs (frame_info
, frame_saved_regs
)
2048 struct frame_info
*frame_info
;
2049 struct frame_saved_regs
*frame_saved_regs
;
2052 struct unwind_table_entry
*u
;
2053 unsigned long inst
, stack_remaining
, save_gr
, save_fr
, save_rp
, save_sp
;
2058 /* Zero out everything. */
2059 memset (frame_saved_regs
, '\0', sizeof (struct frame_saved_regs
));
2061 /* Call dummy frames always look the same, so there's no need to
2062 examine the dummy code to determine locations of saved registers;
2063 instead, let find_dummy_frame_regs fill in the correct offsets
2064 for the saved registers. */
2065 if ((frame_info
->pc
>= frame_info
->frame
2066 && frame_info
->pc
<= (frame_info
->frame
+ CALL_DUMMY_LENGTH
2067 + 32 * 4 + (NUM_REGS
- FP0_REGNUM
) * 8
2069 find_dummy_frame_regs (frame_info
, frame_saved_regs
);
2071 /* Interrupt handlers are special too. They lay out the register
2072 state in the exact same order as the register numbers in GDB. */
2073 if (pc_in_interrupt_handler (frame_info
->pc
))
2075 for (i
= 0; i
< NUM_REGS
; i
++)
2077 /* SP is a little special. */
2079 frame_saved_regs
->regs
[SP_REGNUM
]
2080 = read_memory_integer (frame_info
->frame
+ SP_REGNUM
* 4, 4);
2082 frame_saved_regs
->regs
[i
] = frame_info
->frame
+ i
* 4;
2087 /* Handle signal handler callers. */
2088 if (frame_info
->signal_handler_caller
)
2090 FRAME_FIND_SAVED_REGS_IN_SIGTRAMP (frame_info
, frame_saved_regs
);
2094 /* Get the starting address of the function referred to by the PC
2096 pc
= get_pc_function_start (frame_info
->pc
);
2099 u
= find_unwind_entry (pc
);
2103 /* This is how much of a frame adjustment we need to account for. */
2104 stack_remaining
= u
->Total_frame_size
<< 3;
2106 /* Magic register saves we want to know about. */
2107 save_rp
= u
->Save_RP
;
2108 save_sp
= u
->Save_SP
;
2110 /* Turn the Entry_GR field into a bitmask. */
2112 for (i
= 3; i
< u
->Entry_GR
+ 3; i
++)
2114 /* Frame pointer gets saved into a special location. */
2115 if (u
->Save_SP
&& i
== FP_REGNUM
)
2118 save_gr
|= (1 << i
);
2121 /* Turn the Entry_FR field into a bitmask too. */
2123 for (i
= 12; i
< u
->Entry_FR
+ 12; i
++)
2124 save_fr
|= (1 << i
);
2126 /* The frame always represents the value of %sp at entry to the
2127 current function (and is thus equivalent to the "saved" stack
2129 frame_saved_regs
->regs
[SP_REGNUM
] = frame_info
->frame
;
2131 /* Loop until we find everything of interest or hit a branch.
2133 For unoptimized GCC code and for any HP CC code this will never ever
2134 examine any user instructions.
2136 For optimzied GCC code we're faced with problems. GCC will schedule
2137 its prologue and make prologue instructions available for delay slot
2138 filling. The end result is user code gets mixed in with the prologue
2139 and a prologue instruction may be in the delay slot of the first branch
2142 Some unexpected things are expected with debugging optimized code, so
2143 we allow this routine to walk past user instructions in optimized
2145 while (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0)
2147 status
= target_read_memory (pc
, buf
, 4);
2148 inst
= extract_unsigned_integer (buf
, 4);
2154 /* Note the interesting effects of this instruction. */
2155 stack_remaining
-= prologue_inst_adjust_sp (inst
);
2157 /* There is only one instruction used for saving RP into the stack. */
2158 if (inst
== 0x6bc23fd9)
2161 frame_saved_regs
->regs
[RP_REGNUM
] = frame_info
->frame
- 20;
2164 /* Just note that we found the save of SP into the stack. The
2165 value for frame_saved_regs was computed above. */
2166 if ((inst
& 0xffffc000) == 0x6fc10000)
2169 /* Account for general and floating-point register saves. */
2170 reg
= inst_saves_gr (inst
);
2171 if (reg
>= 3 && reg
<= 18
2172 && (!u
->Save_SP
|| reg
!= FP_REGNUM
))
2174 save_gr
&= ~(1 << reg
);
2176 /* stwm with a positive displacement is a *post modify*. */
2177 if ((inst
>> 26) == 0x1b
2178 && extract_14 (inst
) >= 0)
2179 frame_saved_regs
->regs
[reg
] = frame_info
->frame
;
2182 /* Handle code with and without frame pointers. */
2184 frame_saved_regs
->regs
[reg
]
2185 = frame_info
->frame
+ extract_14 (inst
);
2187 frame_saved_regs
->regs
[reg
]
2188 = frame_info
->frame
+ (u
->Total_frame_size
<< 3)
2189 + extract_14 (inst
);
2194 /* GCC handles callee saved FP regs a little differently.
2196 It emits an instruction to put the value of the start of
2197 the FP store area into %r1. It then uses fstds,ma with
2198 a basereg of %r1 for the stores.
2200 HP CC emits them at the current stack pointer modifying
2201 the stack pointer as it stores each register. */
2203 /* ldo X(%r3),%r1 or ldo X(%r30),%r1. */
2204 if ((inst
& 0xffffc000) == 0x34610000
2205 || (inst
& 0xffffc000) == 0x37c10000)
2206 fp_loc
= extract_14 (inst
);
2208 reg
= inst_saves_fr (inst
);
2209 if (reg
>= 12 && reg
<= 21)
2211 /* Note +4 braindamage below is necessary because the FP status
2212 registers are internally 8 registers rather than the expected
2214 save_fr
&= ~(1 << reg
);
2217 /* 1st HP CC FP register store. After this instruction
2218 we've set enough state that the GCC and HPCC code are
2219 both handled in the same manner. */
2220 frame_saved_regs
->regs
[reg
+ FP4_REGNUM
+ 4] = frame_info
->frame
;
2225 frame_saved_regs
->regs
[reg
+ FP0_REGNUM
+ 4]
2226 = frame_info
->frame
+ fp_loc
;
2231 /* Quit if we hit any kind of branch. This can happen if a prologue
2232 instruction is in the delay slot of the first call/branch. */
2233 if (is_branch (inst
))
2241 #ifdef MAINTENANCE_CMDS
2244 unwind_command (exp
, from_tty
)
2252 struct unwind_table_entry
*u
;
2255 /* If we have an expression, evaluate it and use it as the address. */
2257 if (exp
!= 0 && *exp
!= 0)
2258 address
= parse_and_eval_address (exp
);
2262 xxx
.u
= find_unwind_entry (address
);
2266 printf_unfiltered ("Can't find unwind table entry for PC 0x%x\n", address
);
2270 printf_unfiltered ("%08x\n%08X\n%08X\n%08X\n", xxx
.foo
[0], xxx
.foo
[1], xxx
.foo
[2],
2273 #endif /* MAINTENANCE_CMDS */
2276 _initialize_hppa_tdep ()
2278 #ifdef MAINTENANCE_CMDS
2279 add_cmd ("unwind", class_maintenance
, unwind_command
,
2280 "Print unwind table entry at given address.",
2281 &maintenanceprintlist
);
2282 #endif /* MAINTENANCE_CMDS */