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,
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
)
286 struct objfile
*objfile
;
287 struct unwind_table_entry
*table
;
289 unsigned int entries
, size
;
291 /* We will read the unwind entries into temporary memory, then
292 fill in the actual unwind table. */
297 char *buf
= alloca (size
);
299 bfd_get_section_contents (objfile
->obfd
, section
, buf
, 0, size
);
301 /* Now internalize the information being careful to handle host/target
303 for (i
= 0; i
< entries
; i
++)
305 table
[i
].region_start
= bfd_get_32 (objfile
->obfd
,
308 table
[i
].region_end
= bfd_get_32 (objfile
->obfd
, (bfd_byte
*)buf
);
310 tmp
= bfd_get_32 (objfile
->obfd
, (bfd_byte
*)buf
);
312 table
[i
].Cannot_unwind
= (tmp
>> 31) & 0x1;;
313 table
[i
].Millicode
= (tmp
>> 30) & 0x1;
314 table
[i
].Millicode_save_sr0
= (tmp
>> 29) & 0x1;
315 table
[i
].Region_description
= (tmp
>> 27) & 0x3;
316 table
[i
].reserved1
= (tmp
>> 26) & 0x1;
317 table
[i
].Entry_SR
= (tmp
>> 25) & 0x1;
318 table
[i
].Entry_FR
= (tmp
>> 21) & 0xf;
319 table
[i
].Entry_GR
= (tmp
>> 16) & 0x1f;
320 table
[i
].Args_stored
= (tmp
>> 15) & 0x1;
321 table
[i
].Variable_Frame
= (tmp
>> 14) & 0x1;
322 table
[i
].Separate_Package_Body
= (tmp
>> 13) & 0x1;
323 table
[i
].Frame_Extension_Millicode
= (tmp
>> 12 ) & 0x1;
324 table
[i
].Stack_Overflow_Check
= (tmp
>> 11) & 0x1;
325 table
[i
].Two_Instruction_SP_Increment
= (tmp
>> 10) & 0x1;
326 table
[i
].Ada_Region
= (tmp
>> 9) & 0x1;
327 table
[i
].reserved2
= (tmp
>> 5) & 0xf;
328 table
[i
].Save_SP
= (tmp
>> 4) & 0x1;
329 table
[i
].Save_RP
= (tmp
>> 3) & 0x1;
330 table
[i
].Save_MRP_in_frame
= (tmp
>> 2) & 0x1;
331 table
[i
].extn_ptr_defined
= (tmp
>> 1) & 0x1;
332 table
[i
].Cleanup_defined
= tmp
& 0x1;
333 tmp
= bfd_get_32 (objfile
->obfd
, (bfd_byte
*)buf
);
335 table
[i
].MPE_XL_interrupt_marker
= (tmp
>> 31) & 0x1;
336 table
[i
].HP_UX_interrupt_marker
= (tmp
>> 30) & 0x1;
337 table
[i
].Large_frame
= (tmp
>> 29) & 0x1;
338 table
[i
].reserved4
= (tmp
>> 27) & 0x3;
339 table
[i
].Total_frame_size
= tmp
& 0x7ffffff;
344 /* Read in the backtrace information stored in the `$UNWIND_START$' section of
345 the object file. This info is used mainly by find_unwind_entry() to find
346 out the stack frame size and frame pointer used by procedures. We put
347 everything on the psymbol obstack in the objfile so that it automatically
348 gets freed when the objfile is destroyed. */
351 read_unwind_info (objfile
)
352 struct objfile
*objfile
;
354 asection
*unwind_sec
, *elf_unwind_sec
, *stub_unwind_sec
;
355 unsigned unwind_size
, elf_unwind_size
, stub_unwind_size
, total_size
;
356 unsigned index
, unwind_entries
, elf_unwind_entries
;
357 unsigned stub_entries
, total_entries
;
358 struct obj_unwind_info
*ui
;
360 ui
= obstack_alloc (&objfile
->psymbol_obstack
,
361 sizeof (struct obj_unwind_info
));
367 /* Get hooks to all unwind sections. Note there is no linker-stub unwind
368 section in ELF at the moment. */
369 unwind_sec
= bfd_get_section_by_name (objfile
->obfd
, "$UNWIND_START$");
370 elf_unwind_sec
= bfd_get_section_by_name (objfile
->obfd
, ".PARISC.unwind");
371 stub_unwind_sec
= bfd_get_section_by_name (objfile
->obfd
, "$UNWIND_END$");
373 /* Get sizes and unwind counts for all sections. */
376 unwind_size
= bfd_section_size (objfile
->obfd
, unwind_sec
);
377 unwind_entries
= unwind_size
/ UNWIND_ENTRY_SIZE
;
387 elf_unwind_size
= bfd_section_size (objfile
->obfd
, elf_unwind_sec
);
388 elf_unwind_entries
= elf_unwind_size
/ UNWIND_ENTRY_SIZE
;
393 elf_unwind_entries
= 0;
398 stub_unwind_size
= bfd_section_size (objfile
->obfd
, stub_unwind_sec
);
399 stub_entries
= stub_unwind_size
/ STUB_UNWIND_ENTRY_SIZE
;
403 stub_unwind_size
= 0;
407 /* Compute total number of unwind entries and their total size. */
408 total_entries
= unwind_entries
+ elf_unwind_entries
+ stub_entries
;
409 total_size
= total_entries
* sizeof (struct unwind_table_entry
);
411 /* Allocate memory for the unwind table. */
412 ui
->table
= obstack_alloc (&objfile
->psymbol_obstack
, total_size
);
413 ui
->last
= total_entries
- 1;
415 /* Internalize the standard unwind entries. */
417 internalize_unwinds (objfile
, &ui
->table
[index
], unwind_sec
,
418 unwind_entries
, unwind_size
);
419 index
+= unwind_entries
;
420 internalize_unwinds (objfile
, &ui
->table
[index
], elf_unwind_sec
,
421 elf_unwind_entries
, elf_unwind_size
);
422 index
+= elf_unwind_entries
;
424 /* Now internalize the stub unwind entries. */
425 if (stub_unwind_size
> 0)
428 char *buf
= alloca (stub_unwind_size
);
430 /* Read in the stub unwind entries. */
431 bfd_get_section_contents (objfile
->obfd
, stub_unwind_sec
, buf
,
432 0, stub_unwind_size
);
434 /* Now convert them into regular unwind entries. */
435 for (i
= 0; i
< stub_entries
; i
++, index
++)
437 /* Clear out the next unwind entry. */
438 memset (&ui
->table
[index
], 0, sizeof (struct unwind_table_entry
));
440 /* Convert offset & size into region_start and region_end.
441 Stuff away the stub type into "reserved" fields. */
442 ui
->table
[index
].region_start
= bfd_get_32 (objfile
->obfd
,
445 ui
->table
[index
].stub_type
= bfd_get_8 (objfile
->obfd
,
448 ui
->table
[index
].region_end
449 = ui
->table
[index
].region_start
+ 4 *
450 (bfd_get_16 (objfile
->obfd
, (bfd_byte
*) buf
) - 1);
456 /* Unwind table needs to be kept sorted. */
457 qsort (ui
->table
, total_entries
, sizeof (struct unwind_table_entry
),
458 compare_unwind_entries
);
460 /* Keep a pointer to the unwind information. */
461 objfile
->obj_private
= (PTR
) ui
;
464 /* Lookup the unwind (stack backtrace) info for the given PC. We search all
465 of the objfiles seeking the unwind table entry for this PC. Each objfile
466 contains a sorted list of struct unwind_table_entry. Since we do a binary
467 search of the unwind tables, we depend upon them to be sorted. */
469 static struct unwind_table_entry
*
470 find_unwind_entry(pc
)
473 int first
, middle
, last
;
474 struct objfile
*objfile
;
476 ALL_OBJFILES (objfile
)
478 struct obj_unwind_info
*ui
;
480 ui
= OBJ_UNWIND_INFO (objfile
);
484 read_unwind_info (objfile
);
485 ui
= OBJ_UNWIND_INFO (objfile
);
488 /* First, check the cache */
491 && pc
>= ui
->cache
->region_start
492 && pc
<= ui
->cache
->region_end
)
495 /* Not in the cache, do a binary search */
500 while (first
<= last
)
502 middle
= (first
+ last
) / 2;
503 if (pc
>= ui
->table
[middle
].region_start
504 && pc
<= ui
->table
[middle
].region_end
)
506 ui
->cache
= &ui
->table
[middle
];
507 return &ui
->table
[middle
];
510 if (pc
< ui
->table
[middle
].region_start
)
515 } /* ALL_OBJFILES() */
519 /* start-sanitize-hpread */
520 /* Return the adjustment necessary to make for addresses on the stack
521 as presented by hpread.c.
523 This is necessary because of the stack direction on the PA and the
524 bizarre way in which someone (?) decided they wanted to handle
525 frame pointerless code in GDB. */
527 hpread_adjust_stack_address (func_addr
)
530 struct unwind_table_entry
*u
;
532 u
= find_unwind_entry (func_addr
);
536 return u
->Total_frame_size
<< 3;
538 /* end-sanitize-hpread */
540 /* Called to determine if PC is in an interrupt handler of some
544 pc_in_interrupt_handler (pc
)
547 struct unwind_table_entry
*u
;
548 struct minimal_symbol
*msym_us
;
550 u
= find_unwind_entry (pc
);
554 /* Oh joys. HPUX sets the interrupt bit for _sigreturn even though
555 its frame isn't a pure interrupt frame. Deal with this. */
556 msym_us
= lookup_minimal_symbol_by_pc (pc
);
558 return u
->HP_UX_interrupt_marker
&& !IN_SIGTRAMP (pc
, SYMBOL_NAME (msym_us
));
561 /* Called when no unwind descriptor was found for PC. Returns 1 if it
562 appears that PC is in a linker stub. */
565 pc_in_linker_stub (pc
)
568 int found_magic_instruction
= 0;
572 /* If unable to read memory, assume pc is not in a linker stub. */
573 if (target_read_memory (pc
, buf
, 4) != 0)
576 /* We are looking for something like
578 ; $$dyncall jams RP into this special spot in the frame (RP')
579 ; before calling the "call stub"
582 ldsid (rp),r1 ; Get space associated with RP into r1
583 mtsp r1,sp ; Move it into space register 0
584 be,n 0(sr0),rp) ; back to your regularly scheduled program
587 /* Maximum known linker stub size is 4 instructions. Search forward
588 from the given PC, then backward. */
589 for (i
= 0; i
< 4; i
++)
591 /* If we hit something with an unwind, stop searching this direction. */
593 if (find_unwind_entry (pc
+ i
* 4) != 0)
596 /* Check for ldsid (rp),r1 which is the magic instruction for a
597 return from a cross-space function call. */
598 if (read_memory_integer (pc
+ i
* 4, 4) == 0x004010a1)
600 found_magic_instruction
= 1;
603 /* Add code to handle long call/branch and argument relocation stubs
607 if (found_magic_instruction
!= 0)
610 /* Now look backward. */
611 for (i
= 0; i
< 4; i
++)
613 /* If we hit something with an unwind, stop searching this direction. */
615 if (find_unwind_entry (pc
- i
* 4) != 0)
618 /* Check for ldsid (rp),r1 which is the magic instruction for a
619 return from a cross-space function call. */
620 if (read_memory_integer (pc
- i
* 4, 4) == 0x004010a1)
622 found_magic_instruction
= 1;
625 /* Add code to handle long call/branch and argument relocation stubs
628 return found_magic_instruction
;
632 find_return_regnum(pc
)
635 struct unwind_table_entry
*u
;
637 u
= find_unwind_entry (pc
);
648 /* Return size of frame, or -1 if we should use a frame pointer. */
650 find_proc_framesize (pc
)
653 struct unwind_table_entry
*u
;
654 struct minimal_symbol
*msym_us
;
656 u
= find_unwind_entry (pc
);
660 if (pc_in_linker_stub (pc
))
661 /* Linker stubs have a zero size frame. */
667 msym_us
= lookup_minimal_symbol_by_pc (pc
);
669 /* If Save_SP is set, and we're not in an interrupt or signal caller,
670 then we have a frame pointer. Use it. */
671 if (u
->Save_SP
&& !pc_in_interrupt_handler (pc
)
672 && !IN_SIGTRAMP (pc
, SYMBOL_NAME (msym_us
)))
675 return u
->Total_frame_size
<< 3;
678 /* Return offset from sp at which rp is saved, or 0 if not saved. */
679 static int rp_saved
PARAMS ((CORE_ADDR
));
685 struct unwind_table_entry
*u
;
687 u
= find_unwind_entry (pc
);
691 if (pc_in_linker_stub (pc
))
692 /* This is the so-called RP'. */
700 else if (u
->stub_type
!= 0)
702 switch (u
->stub_type
)
706 case PARAMETER_RELOCATION
:
717 frameless_function_invocation (frame
)
718 struct frame_info
*frame
;
720 struct unwind_table_entry
*u
;
722 u
= find_unwind_entry (frame
->pc
);
727 return (u
->Total_frame_size
== 0 && u
->stub_type
== 0);
731 saved_pc_after_call (frame
)
732 struct frame_info
*frame
;
736 struct unwind_table_entry
*u
;
738 ret_regnum
= find_return_regnum (get_frame_pc (frame
));
739 pc
= read_register (ret_regnum
) & ~0x3;
741 /* If PC is in a linker stub, then we need to dig the address
742 the stub will return to out of the stack. */
743 u
= find_unwind_entry (pc
);
744 if (u
&& u
->stub_type
!= 0)
745 return frame_saved_pc (frame
);
751 frame_saved_pc (frame
)
752 struct frame_info
*frame
;
754 CORE_ADDR pc
= get_frame_pc (frame
);
755 struct unwind_table_entry
*u
;
757 /* BSD, HPUX & OSF1 all lay out the hardware state in the same manner
758 at the base of the frame in an interrupt handler. Registers within
759 are saved in the exact same order as GDB numbers registers. How
761 if (pc_in_interrupt_handler (pc
))
762 return read_memory_integer (frame
->frame
+ PC_REGNUM
* 4, 4) & ~0x3;
764 /* Deal with signal handler caller frames too. */
765 if (frame
->signal_handler_caller
)
768 FRAME_SAVED_PC_IN_SIGTRAMP (frame
, &rp
);
772 if (frameless_function_invocation (frame
))
776 ret_regnum
= find_return_regnum (pc
);
778 /* If the next frame is an interrupt frame or a signal
779 handler caller, then we need to look in the saved
780 register area to get the return pointer (the values
781 in the registers may not correspond to anything useful). */
783 && (frame
->next
->signal_handler_caller
784 || pc_in_interrupt_handler (frame
->next
->pc
)))
786 struct frame_saved_regs saved_regs
;
788 get_frame_saved_regs (frame
->next
, &saved_regs
);
789 if (read_memory_integer (saved_regs
.regs
[FLAGS_REGNUM
], 4) & 0x2)
791 pc
= read_memory_integer (saved_regs
.regs
[31], 4) & ~0x3;
793 /* Syscalls are really two frames. The syscall stub itself
794 with a return pointer in %rp and the kernel call with
795 a return pointer in %r31. We return the %rp variant
796 if %r31 is the same as frame->pc. */
798 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
801 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
804 pc
= read_register (ret_regnum
) & ~0x3;
811 rp_offset
= rp_saved (pc
);
812 /* Similar to code in frameless function case. If the next
813 frame is a signal or interrupt handler, then dig the right
814 information out of the saved register info. */
817 && (frame
->next
->signal_handler_caller
818 || pc_in_interrupt_handler (frame
->next
->pc
)))
820 struct frame_saved_regs saved_regs
;
822 get_frame_saved_regs (frame
->next
, &saved_regs
);
823 if (read_memory_integer (saved_regs
.regs
[FLAGS_REGNUM
], 4) & 0x2)
825 pc
= read_memory_integer (saved_regs
.regs
[31], 4) & ~0x3;
827 /* Syscalls are really two frames. The syscall stub itself
828 with a return pointer in %rp and the kernel call with
829 a return pointer in %r31. We return the %rp variant
830 if %r31 is the same as frame->pc. */
832 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
835 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
837 else if (rp_offset
== 0)
838 pc
= read_register (RP_REGNUM
) & ~0x3;
840 pc
= read_memory_integer (frame
->frame
+ rp_offset
, 4) & ~0x3;
843 /* If PC is inside a linker stub, then dig out the address the stub
845 u
= find_unwind_entry (pc
);
846 if (u
&& u
->stub_type
!= 0)
852 /* We need to correct the PC and the FP for the outermost frame when we are
856 init_extra_frame_info (fromleaf
, frame
)
858 struct frame_info
*frame
;
863 if (frame
->next
&& !fromleaf
)
866 /* If the next frame represents a frameless function invocation
867 then we have to do some adjustments that are normally done by
868 FRAME_CHAIN. (FRAME_CHAIN is not called in this case.) */
871 /* Find the framesize of *this* frame without peeking at the PC
872 in the current frame structure (it isn't set yet). */
873 framesize
= find_proc_framesize (FRAME_SAVED_PC (get_next_frame (frame
)));
875 /* Now adjust our base frame accordingly. If we have a frame pointer
876 use it, else subtract the size of this frame from the current
877 frame. (we always want frame->frame to point at the lowest address
880 frame
->frame
= read_register (FP_REGNUM
);
882 frame
->frame
-= framesize
;
886 flags
= read_register (FLAGS_REGNUM
);
887 if (flags
& 2) /* In system call? */
888 frame
->pc
= read_register (31) & ~0x3;
890 /* The outermost frame is always derived from PC-framesize
892 One might think frameless innermost frames should have
893 a frame->frame that is the same as the parent's frame->frame.
894 That is wrong; frame->frame in that case should be the *high*
895 address of the parent's frame. It's complicated as hell to
896 explain, but the parent *always* creates some stack space for
897 the child. So the child actually does have a frame of some
898 sorts, and its base is the high address in its parent's frame. */
899 framesize
= find_proc_framesize(frame
->pc
);
901 frame
->frame
= read_register (FP_REGNUM
);
903 frame
->frame
= read_register (SP_REGNUM
) - framesize
;
906 /* Given a GDB frame, determine the address of the calling function's frame.
907 This will be used to create a new GDB frame struct, and then
908 INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame.
910 This may involve searching through prologues for several functions
911 at boundaries where GCC calls HP C code, or where code which has
912 a frame pointer calls code without a frame pointer. */
916 struct frame_info
*frame
;
918 int my_framesize
, caller_framesize
;
919 struct unwind_table_entry
*u
;
920 CORE_ADDR frame_base
;
922 /* Handle HPUX, BSD, and OSF1 style interrupt frames first. These
923 are easy; at *sp we have a full save state strucutre which we can
924 pull the old stack pointer from. Also see frame_saved_pc for
925 code to dig a saved PC out of the save state structure. */
926 if (pc_in_interrupt_handler (frame
->pc
))
927 frame_base
= read_memory_integer (frame
->frame
+ SP_REGNUM
* 4, 4);
928 else if (frame
->signal_handler_caller
)
930 FRAME_BASE_BEFORE_SIGTRAMP (frame
, &frame_base
);
933 frame_base
= frame
->frame
;
935 /* Get frame sizes for the current frame and the frame of the
937 my_framesize
= find_proc_framesize (frame
->pc
);
938 caller_framesize
= find_proc_framesize (FRAME_SAVED_PC(frame
));
940 /* If caller does not have a frame pointer, then its frame
941 can be found at current_frame - caller_framesize. */
942 if (caller_framesize
!= -1)
943 return frame_base
- caller_framesize
;
945 /* Both caller and callee have frame pointers and are GCC compiled
946 (SAVE_SP bit in unwind descriptor is on for both functions.
947 The previous frame pointer is found at the top of the current frame. */
948 if (caller_framesize
== -1 && my_framesize
== -1)
949 return read_memory_integer (frame_base
, 4);
951 /* Caller has a frame pointer, but callee does not. This is a little
952 more difficult as GCC and HP C lay out locals and callee register save
953 areas very differently.
955 The previous frame pointer could be in a register, or in one of
956 several areas on the stack.
958 Walk from the current frame to the innermost frame examining
959 unwind descriptors to determine if %r3 ever gets saved into the
960 stack. If so return whatever value got saved into the stack.
961 If it was never saved in the stack, then the value in %r3 is still
964 We use information from unwind descriptors to determine if %r3
965 is saved into the stack (Entry_GR field has this information). */
969 u
= find_unwind_entry (frame
->pc
);
973 /* We could find this information by examining prologues. I don't
974 think anyone has actually written any tools (not even "strip")
975 which leave them out of an executable, so maybe this is a moot
977 warning ("Unable to find unwind for PC 0x%x -- Help!", frame
->pc
);
981 /* Entry_GR specifies the number of callee-saved general registers
982 saved in the stack. It starts at %r3, so %r3 would be 1. */
983 if (u
->Entry_GR
>= 1 || u
->Save_SP
984 || frame
->signal_handler_caller
985 || pc_in_interrupt_handler (frame
->pc
))
993 /* We may have walked down the chain into a function with a frame
996 && !frame
->signal_handler_caller
997 && !pc_in_interrupt_handler (frame
->pc
))
998 return read_memory_integer (frame
->frame
, 4);
999 /* %r3 was saved somewhere in the stack. Dig it out. */
1002 struct frame_saved_regs saved_regs
;
1004 get_frame_saved_regs (frame
, &saved_regs
);
1005 return read_memory_integer (saved_regs
.regs
[FP_REGNUM
], 4);
1010 /* The value in %r3 was never saved into the stack (thus %r3 still
1011 holds the value of the previous frame pointer). */
1012 return read_register (FP_REGNUM
);
1017 /* To see if a frame chain is valid, see if the caller looks like it
1018 was compiled with gcc. */
1021 frame_chain_valid (chain
, thisframe
)
1023 struct frame_info
*thisframe
;
1025 struct minimal_symbol
*msym_us
;
1026 struct minimal_symbol
*msym_start
;
1027 struct unwind_table_entry
*u
, *next_u
= NULL
;
1028 struct frame_info
*next
;
1033 u
= find_unwind_entry (thisframe
->pc
);
1038 /* We can't just check that the same of msym_us is "_start", because
1039 someone idiotically decided that they were going to make a Ltext_end
1040 symbol with the same address. This Ltext_end symbol is totally
1041 indistinguishable (as nearly as I can tell) from the symbol for a function
1042 which is (legitimately, since it is in the user's namespace)
1043 named Ltext_end, so we can't just ignore it. */
1044 msym_us
= lookup_minimal_symbol_by_pc (FRAME_SAVED_PC (thisframe
));
1045 msym_start
= lookup_minimal_symbol ("_start", NULL
);
1048 && SYMBOL_VALUE_ADDRESS (msym_us
) == SYMBOL_VALUE_ADDRESS (msym_start
))
1051 next
= get_next_frame (thisframe
);
1053 next_u
= find_unwind_entry (next
->pc
);
1055 /* If this frame does not save SP, has no stack, isn't a stub,
1056 and doesn't "call" an interrupt routine or signal handler caller,
1057 then its not valid. */
1058 if (u
->Save_SP
|| u
->Total_frame_size
|| u
->stub_type
!= 0
1059 || (thisframe
->next
&& thisframe
->next
->signal_handler_caller
)
1060 || (next_u
&& next_u
->HP_UX_interrupt_marker
))
1063 if (pc_in_linker_stub (thisframe
->pc
))
1070 * These functions deal with saving and restoring register state
1071 * around a function call in the inferior. They keep the stack
1072 * double-word aligned; eventually, on an hp700, the stack will have
1073 * to be aligned to a 64-byte boundary.
1079 register CORE_ADDR sp
;
1080 register int regnum
;
1084 /* Space for "arguments"; the RP goes in here. */
1085 sp
= read_register (SP_REGNUM
) + 48;
1086 int_buffer
= read_register (RP_REGNUM
) | 0x3;
1087 write_memory (sp
- 20, (char *)&int_buffer
, 4);
1089 int_buffer
= read_register (FP_REGNUM
);
1090 write_memory (sp
, (char *)&int_buffer
, 4);
1092 write_register (FP_REGNUM
, sp
);
1096 for (regnum
= 1; regnum
< 32; regnum
++)
1097 if (regnum
!= RP_REGNUM
&& regnum
!= FP_REGNUM
)
1098 sp
= push_word (sp
, read_register (regnum
));
1102 for (regnum
= FP0_REGNUM
; regnum
< NUM_REGS
; regnum
++)
1104 read_register_bytes (REGISTER_BYTE (regnum
), (char *)&freg_buffer
, 8);
1105 sp
= push_bytes (sp
, (char *)&freg_buffer
, 8);
1107 sp
= push_word (sp
, read_register (IPSW_REGNUM
));
1108 sp
= push_word (sp
, read_register (SAR_REGNUM
));
1109 sp
= push_word (sp
, read_register (PCOQ_HEAD_REGNUM
));
1110 sp
= push_word (sp
, read_register (PCSQ_HEAD_REGNUM
));
1111 sp
= push_word (sp
, read_register (PCOQ_TAIL_REGNUM
));
1112 sp
= push_word (sp
, read_register (PCSQ_TAIL_REGNUM
));
1113 write_register (SP_REGNUM
, sp
);
1116 find_dummy_frame_regs (frame
, frame_saved_regs
)
1117 struct frame_info
*frame
;
1118 struct frame_saved_regs
*frame_saved_regs
;
1120 CORE_ADDR fp
= frame
->frame
;
1123 frame_saved_regs
->regs
[RP_REGNUM
] = fp
- 20 & ~0x3;
1124 frame_saved_regs
->regs
[FP_REGNUM
] = fp
;
1125 frame_saved_regs
->regs
[1] = fp
+ 8;
1127 for (fp
+= 12, i
= 3; i
< 32; i
++)
1131 frame_saved_regs
->regs
[i
] = fp
;
1137 for (i
= FP0_REGNUM
; i
< NUM_REGS
; i
++, fp
+= 8)
1138 frame_saved_regs
->regs
[i
] = fp
;
1140 frame_saved_regs
->regs
[IPSW_REGNUM
] = fp
;
1141 frame_saved_regs
->regs
[SAR_REGNUM
] = fp
+ 4;
1142 frame_saved_regs
->regs
[PCOQ_HEAD_REGNUM
] = fp
+ 8;
1143 frame_saved_regs
->regs
[PCSQ_HEAD_REGNUM
] = fp
+ 12;
1144 frame_saved_regs
->regs
[PCOQ_TAIL_REGNUM
] = fp
+ 16;
1145 frame_saved_regs
->regs
[PCSQ_TAIL_REGNUM
] = fp
+ 20;
1151 register struct frame_info
*frame
= get_current_frame ();
1152 register CORE_ADDR fp
;
1153 register int regnum
;
1154 struct frame_saved_regs fsr
;
1157 fp
= FRAME_FP (frame
);
1158 get_frame_saved_regs (frame
, &fsr
);
1160 #ifndef NO_PC_SPACE_QUEUE_RESTORE
1161 if (fsr
.regs
[IPSW_REGNUM
]) /* Restoring a call dummy frame */
1162 restore_pc_queue (&fsr
);
1165 for (regnum
= 31; regnum
> 0; regnum
--)
1166 if (fsr
.regs
[regnum
])
1167 write_register (regnum
, read_memory_integer (fsr
.regs
[regnum
], 4));
1169 for (regnum
= NUM_REGS
- 1; regnum
>= FP0_REGNUM
; regnum
--)
1170 if (fsr
.regs
[regnum
])
1172 read_memory (fsr
.regs
[regnum
], (char *)&freg_buffer
, 8);
1173 write_register_bytes (REGISTER_BYTE (regnum
), (char *)&freg_buffer
, 8);
1176 if (fsr
.regs
[IPSW_REGNUM
])
1177 write_register (IPSW_REGNUM
,
1178 read_memory_integer (fsr
.regs
[IPSW_REGNUM
], 4));
1180 if (fsr
.regs
[SAR_REGNUM
])
1181 write_register (SAR_REGNUM
,
1182 read_memory_integer (fsr
.regs
[SAR_REGNUM
], 4));
1184 /* If the PC was explicitly saved, then just restore it. */
1185 if (fsr
.regs
[PCOQ_TAIL_REGNUM
])
1186 write_register (PCOQ_TAIL_REGNUM
,
1187 read_memory_integer (fsr
.regs
[PCOQ_TAIL_REGNUM
], 4));
1189 /* Else use the value in %rp to set the new PC. */
1191 target_write_pc (read_register (RP_REGNUM
), 0);
1193 write_register (FP_REGNUM
, read_memory_integer (fp
, 4));
1195 if (fsr
.regs
[IPSW_REGNUM
]) /* call dummy */
1196 write_register (SP_REGNUM
, fp
- 48);
1198 write_register (SP_REGNUM
, fp
);
1200 flush_cached_frames ();
1204 * After returning to a dummy on the stack, restore the instruction
1205 * queue space registers. */
1208 restore_pc_queue (fsr
)
1209 struct frame_saved_regs
*fsr
;
1211 CORE_ADDR pc
= read_pc ();
1212 CORE_ADDR new_pc
= read_memory_integer (fsr
->regs
[PCOQ_HEAD_REGNUM
], 4);
1214 struct target_waitstatus w
;
1217 /* Advance past break instruction in the call dummy. */
1218 write_register (PCOQ_HEAD_REGNUM
, pc
+ 4);
1219 write_register (PCOQ_TAIL_REGNUM
, pc
+ 8);
1222 * HPUX doesn't let us set the space registers or the space
1223 * registers of the PC queue through ptrace. Boo, hiss.
1224 * Conveniently, the call dummy has this sequence of instructions
1229 * So, load up the registers and single step until we are in the
1233 write_register (21, read_memory_integer (fsr
->regs
[PCSQ_HEAD_REGNUM
], 4));
1234 write_register (22, new_pc
);
1236 for (insn_count
= 0; insn_count
< 3; insn_count
++)
1238 /* FIXME: What if the inferior gets a signal right now? Want to
1239 merge this into wait_for_inferior (as a special kind of
1240 watchpoint? By setting a breakpoint at the end? Is there
1241 any other choice? Is there *any* way to do this stuff with
1242 ptrace() or some equivalent?). */
1244 target_wait (inferior_pid
, &w
);
1246 if (w
.kind
== TARGET_WAITKIND_SIGNALLED
)
1248 stop_signal
= w
.value
.sig
;
1249 terminal_ours_for_output ();
1250 printf_unfiltered ("\nProgram terminated with signal %s, %s.\n",
1251 target_signal_to_name (stop_signal
),
1252 target_signal_to_string (stop_signal
));
1253 gdb_flush (gdb_stdout
);
1257 target_terminal_ours ();
1258 target_fetch_registers (-1);
1263 hppa_push_arguments (nargs
, args
, sp
, struct_return
, struct_addr
)
1268 CORE_ADDR struct_addr
;
1270 /* array of arguments' offsets */
1271 int *offset
= (int *)alloca(nargs
* sizeof (int));
1275 for (i
= 0; i
< nargs
; i
++)
1277 /* Coerce chars to int & float to double if necessary */
1278 args
[i
] = value_arg_coerce (args
[i
]);
1280 cum
+= TYPE_LENGTH (VALUE_TYPE (args
[i
]));
1282 /* value must go at proper alignment. Assume alignment is a
1284 alignment
= hppa_alignof (VALUE_TYPE (args
[i
]));
1285 if (cum
% alignment
)
1286 cum
= (cum
+ alignment
) & -alignment
;
1289 sp
+= max ((cum
+ 7) & -8, 16);
1291 for (i
= 0; i
< nargs
; i
++)
1292 write_memory (sp
+ offset
[i
], VALUE_CONTENTS (args
[i
]),
1293 TYPE_LENGTH (VALUE_TYPE (args
[i
])));
1296 write_register (28, struct_addr
);
1301 * Insert the specified number of args and function address
1302 * into a call sequence of the above form stored at DUMMYNAME.
1304 * On the hppa we need to call the stack dummy through $$dyncall.
1305 * Therefore our version of FIX_CALL_DUMMY takes an extra argument,
1306 * real_pc, which is the location where gdb should start up the
1307 * inferior to do the function call.
1311 hppa_fix_call_dummy (dummy
, pc
, fun
, nargs
, args
, type
, gcc_p
)
1320 CORE_ADDR dyncall_addr
, sr4export_addr
;
1321 struct minimal_symbol
*msymbol
;
1322 int flags
= read_register (FLAGS_REGNUM
);
1323 struct unwind_table_entry
*u
;
1325 msymbol
= lookup_minimal_symbol ("$$dyncall", (struct objfile
*) NULL
);
1326 if (msymbol
== NULL
)
1327 error ("Can't find an address for $$dyncall trampoline");
1329 dyncall_addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
1331 /* FUN could be a procedure label, in which case we have to get
1332 its real address and the value of its GOT/DP. */
1335 /* Get the GOT/DP value for the target function. It's
1336 at *(fun+4). Note the call dummy is *NOT* allowed to
1337 trash %r19 before calling the target function. */
1338 write_register (19, read_memory_integer ((fun
& ~0x3) + 4, 4));
1340 /* Now get the real address for the function we are calling, it's
1342 fun
= (CORE_ADDR
) read_memory_integer (fun
& ~0x3, 4);
1345 /* If we are calling an import stub (eg calling into a dynamic library)
1346 then have sr4export call the magic __d_plt_call routine which is linked
1347 in from end.o. (You can't use _sr4export to call the import stub as
1348 the value in sp-24 will get fried and you end up returning to the
1349 wrong location. You can't call the import stub directly as the code
1350 to bind the PLT entry to a function can't return to a stack address.) */
1351 u
= find_unwind_entry (fun
);
1352 if (u
&& u
->stub_type
== IMPORT
)
1355 msymbol
= lookup_minimal_symbol ("__d_plt_call", (struct objfile
*) NULL
);
1356 if (msymbol
== NULL
)
1357 error ("Can't find an address for __d_plt_call trampoline");
1359 /* This is where sr4export will jump to. */
1360 new_fun
= SYMBOL_VALUE_ADDRESS (msymbol
);
1362 /* We have to store the address of the stub in __shlib_funcptr. */
1363 msymbol
= lookup_minimal_symbol ("__shlib_funcptr",
1364 (struct objfile
*)NULL
);
1365 if (msymbol
== NULL
)
1366 error ("Can't find an address for __shlib_funcptr");
1368 target_write_memory (SYMBOL_VALUE_ADDRESS (msymbol
), (char *)&fun
, 4);
1373 /* We still need sr4export's address too. */
1374 msymbol
= lookup_minimal_symbol ("_sr4export", (struct objfile
*) NULL
);
1375 if (msymbol
== NULL
)
1376 error ("Can't find an address for _sr4export trampoline");
1378 sr4export_addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
1380 store_unsigned_integer
1381 (&dummy
[9*REGISTER_SIZE
],
1383 deposit_21 (fun
>> 11,
1384 extract_unsigned_integer (&dummy
[9*REGISTER_SIZE
],
1386 store_unsigned_integer
1387 (&dummy
[10*REGISTER_SIZE
],
1389 deposit_14 (fun
& MASK_11
,
1390 extract_unsigned_integer (&dummy
[10*REGISTER_SIZE
],
1392 store_unsigned_integer
1393 (&dummy
[12*REGISTER_SIZE
],
1395 deposit_21 (sr4export_addr
>> 11,
1396 extract_unsigned_integer (&dummy
[12*REGISTER_SIZE
],
1398 store_unsigned_integer
1399 (&dummy
[13*REGISTER_SIZE
],
1401 deposit_14 (sr4export_addr
& MASK_11
,
1402 extract_unsigned_integer (&dummy
[13*REGISTER_SIZE
],
1405 write_register (22, pc
);
1407 /* If we are in a syscall, then we should call the stack dummy
1408 directly. $$dyncall is not needed as the kernel sets up the
1409 space id registers properly based on the value in %r31. In
1410 fact calling $$dyncall will not work because the value in %r22
1411 will be clobbered on the syscall exit path. */
1415 return dyncall_addr
;
1419 /* Get the PC from %r31 if currently in a syscall. Also mask out privilege
1423 target_read_pc (pid
)
1426 int flags
= read_register (FLAGS_REGNUM
);
1429 return read_register (31) & ~0x3;
1430 return read_register (PC_REGNUM
) & ~0x3;
1433 /* Write out the PC. If currently in a syscall, then also write the new
1434 PC value into %r31. */
1437 target_write_pc (v
, pid
)
1441 int flags
= read_register (FLAGS_REGNUM
);
1443 /* If in a syscall, then set %r31. Also make sure to get the
1444 privilege bits set correctly. */
1446 write_register (31, (long) (v
| 0x3));
1448 write_register (PC_REGNUM
, (long) v
);
1449 write_register (NPC_REGNUM
, (long) v
+ 4);
1452 /* return the alignment of a type in bytes. Structures have the maximum
1453 alignment required by their fields. */
1459 int max_align
, align
, i
;
1460 switch (TYPE_CODE (arg
))
1465 return TYPE_LENGTH (arg
);
1466 case TYPE_CODE_ARRAY
:
1467 return hppa_alignof (TYPE_FIELD_TYPE (arg
, 0));
1468 case TYPE_CODE_STRUCT
:
1469 case TYPE_CODE_UNION
:
1471 for (i
= 0; i
< TYPE_NFIELDS (arg
); i
++)
1473 /* Bit fields have no real alignment. */
1474 if (!TYPE_FIELD_BITPOS (arg
, i
))
1476 align
= hppa_alignof (TYPE_FIELD_TYPE (arg
, i
));
1477 max_align
= max (max_align
, align
);
1486 /* Print the register regnum, or all registers if regnum is -1 */
1488 pa_do_registers_info (regnum
, fpregs
)
1492 char raw_regs
[REGISTER_BYTES
];
1495 for (i
= 0; i
< NUM_REGS
; i
++)
1496 read_relative_register_raw_bytes (i
, raw_regs
+ REGISTER_BYTE (i
));
1498 pa_print_registers (raw_regs
, regnum
, fpregs
);
1499 else if (regnum
< FP0_REGNUM
)
1500 printf_unfiltered ("%s %x\n", reg_names
[regnum
], *(long *)(raw_regs
+
1501 REGISTER_BYTE (regnum
)));
1503 pa_print_fp_reg (regnum
);
1506 pa_print_registers (raw_regs
, regnum
, fpregs
)
1513 for (i
= 0; i
< 18; i
++)
1514 printf_unfiltered ("%8.8s: %8x %8.8s: %8x %8.8s: %8x %8.8s: %8x\n",
1516 *(int *)(raw_regs
+ REGISTER_BYTE (i
)),
1518 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 18)),
1520 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 36)),
1522 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 54)));
1525 for (i
= 72; i
< NUM_REGS
; i
++)
1526 pa_print_fp_reg (i
);
1532 unsigned char raw_buffer
[MAX_REGISTER_RAW_SIZE
];
1533 unsigned char virtual_buffer
[MAX_REGISTER_VIRTUAL_SIZE
];
1535 /* Get 32bits of data. */
1536 read_relative_register_raw_bytes (i
, raw_buffer
);
1538 /* Put it in the buffer. No conversions are ever necessary. */
1539 memcpy (virtual_buffer
, raw_buffer
, REGISTER_RAW_SIZE (i
));
1541 fputs_filtered (reg_names
[i
], gdb_stdout
);
1542 print_spaces_filtered (8 - strlen (reg_names
[i
]), gdb_stdout
);
1543 fputs_filtered ("(single precision) ", gdb_stdout
);
1545 val_print (REGISTER_VIRTUAL_TYPE (i
), virtual_buffer
, 0, gdb_stdout
, 0,
1546 1, 0, Val_pretty_default
);
1547 printf_filtered ("\n");
1549 /* If "i" is even, then this register can also be a double-precision
1550 FP register. Dump it out as such. */
1553 /* Get the data in raw format for the 2nd half. */
1554 read_relative_register_raw_bytes (i
+ 1, raw_buffer
);
1556 /* Copy it into the appropriate part of the virtual buffer. */
1557 memcpy (virtual_buffer
+ REGISTER_RAW_SIZE (i
), raw_buffer
,
1558 REGISTER_RAW_SIZE (i
));
1560 /* Dump it as a double. */
1561 fputs_filtered (reg_names
[i
], gdb_stdout
);
1562 print_spaces_filtered (8 - strlen (reg_names
[i
]), gdb_stdout
);
1563 fputs_filtered ("(double precision) ", gdb_stdout
);
1565 val_print (builtin_type_double
, virtual_buffer
, 0, gdb_stdout
, 0,
1566 1, 0, Val_pretty_default
);
1567 printf_filtered ("\n");
1571 /* Figure out if PC is in a trampoline, and if so find out where
1572 the trampoline will jump to. If not in a trampoline, return zero.
1574 Simple code examination probably is not a good idea since the code
1575 sequences in trampolines can also appear in user code.
1577 We use unwinds and information from the minimal symbol table to
1578 determine when we're in a trampoline. This won't work for ELF
1579 (yet) since it doesn't create stub unwind entries. Whether or
1580 not ELF will create stub unwinds or normal unwinds for linker
1581 stubs is still being debated.
1583 This should handle simple calls through dyncall or sr4export,
1584 long calls, argument relocation stubs, and dyncall/sr4export
1585 calling an argument relocation stub. It even handles some stubs
1586 used in dynamic executables. */
1589 skip_trampoline_code (pc
, name
)
1594 long prev_inst
, curr_inst
, loc
;
1595 static CORE_ADDR dyncall
= 0;
1596 static CORE_ADDR sr4export
= 0;
1597 struct minimal_symbol
*msym
;
1598 struct unwind_table_entry
*u
;
1600 /* FIXME XXX - dyncall and sr4export must be initialized whenever we get a
1605 msym
= lookup_minimal_symbol ("$$dyncall", NULL
);
1607 dyncall
= SYMBOL_VALUE_ADDRESS (msym
);
1614 msym
= lookup_minimal_symbol ("_sr4export", NULL
);
1616 sr4export
= SYMBOL_VALUE_ADDRESS (msym
);
1621 /* Addresses passed to dyncall may *NOT* be the actual address
1622 of the function. So we may have to do something special. */
1625 pc
= (CORE_ADDR
) read_register (22);
1627 /* If bit 30 (counting from the left) is on, then pc is the address of
1628 the PLT entry for this function, not the address of the function
1629 itself. Bit 31 has meaning too, but only for MPE. */
1631 pc
= (CORE_ADDR
) read_memory_integer (pc
& ~0x3, 4);
1633 else if (pc
== sr4export
)
1634 pc
= (CORE_ADDR
) (read_register (22));
1636 /* Get the unwind descriptor corresponding to PC, return zero
1637 if no unwind was found. */
1638 u
= find_unwind_entry (pc
);
1642 /* If this isn't a linker stub, then return now. */
1643 if (u
->stub_type
== 0)
1644 return orig_pc
== pc
? 0 : pc
& ~0x3;
1646 /* It's a stub. Search for a branch and figure out where it goes.
1647 Note we have to handle multi insn branch sequences like ldil;ble.
1648 Most (all?) other branches can be determined by examining the contents
1649 of certain registers and the stack. */
1655 /* Make sure we haven't walked outside the range of this stub. */
1656 if (u
!= find_unwind_entry (loc
))
1658 warning ("Unable to find branch in linker stub");
1659 return orig_pc
== pc
? 0 : pc
& ~0x3;
1662 prev_inst
= curr_inst
;
1663 curr_inst
= read_memory_integer (loc
, 4);
1665 /* Does it look like a branch external using %r1? Then it's the
1666 branch from the stub to the actual function. */
1667 if ((curr_inst
& 0xffe0e000) == 0xe0202000)
1669 /* Yup. See if the previous instruction loaded
1670 a value into %r1. If so compute and return the jump address. */
1671 if ((prev_inst
& 0xffe00000) == 0x20200000)
1672 return (extract_21 (prev_inst
) + extract_17 (curr_inst
)) & ~0x3;
1675 warning ("Unable to find ldil X,%%r1 before ble Y(%%sr4,%%r1).");
1676 return orig_pc
== pc
? 0 : pc
& ~0x3;
1680 /* Does it look like bl X,%rp or bl X,%r0? Another way to do a
1681 branch from the stub to the actual function. */
1682 else if ((curr_inst
& 0xffe0e000) == 0xe8400000
1683 || (curr_inst
& 0xffe0e000) == 0xe8000000)
1684 return (loc
+ extract_17 (curr_inst
) + 8) & ~0x3;
1686 /* Does it look like bv (rp)? Note this depends on the
1687 current stack pointer being the same as the stack
1688 pointer in the stub itself! This is a branch on from the
1689 stub back to the original caller. */
1690 else if ((curr_inst
& 0xffe0e000) == 0xe840c000)
1692 /* Yup. See if the previous instruction loaded
1694 if (prev_inst
== 0x4bc23ff1)
1695 return (read_memory_integer
1696 (read_register (SP_REGNUM
) - 8, 4)) & ~0x3;
1699 warning ("Unable to find restore of %%rp before bv (%%rp).");
1700 return orig_pc
== pc
? 0 : pc
& ~0x3;
1704 /* What about be,n 0(sr0,%rp)? It's just another way we return to
1705 the original caller from the stub. Used in dynamic executables. */
1706 else if (curr_inst
== 0xe0400002)
1708 /* The value we jump to is sitting in sp - 24. But that's
1709 loaded several instructions before the be instruction.
1710 I guess we could check for the previous instruction being
1711 mtsp %r1,%sr0 if we want to do sanity checking. */
1712 return (read_memory_integer
1713 (read_register (SP_REGNUM
) - 24, 4)) & ~0x3;
1716 /* Haven't found the branch yet, but we're still in the stub.
1722 /* For the given instruction (INST), return any adjustment it makes
1723 to the stack pointer or zero for no adjustment.
1725 This only handles instructions commonly found in prologues. */
1728 prologue_inst_adjust_sp (inst
)
1731 /* This must persist across calls. */
1732 static int save_high21
;
1734 /* The most common way to perform a stack adjustment ldo X(sp),sp */
1735 if ((inst
& 0xffffc000) == 0x37de0000)
1736 return extract_14 (inst
);
1739 if ((inst
& 0xffe00000) == 0x6fc00000)
1740 return extract_14 (inst
);
1742 /* addil high21,%r1; ldo low11,(%r1),%r30)
1743 save high bits in save_high21 for later use. */
1744 if ((inst
& 0xffe00000) == 0x28200000)
1746 save_high21
= extract_21 (inst
);
1750 if ((inst
& 0xffff0000) == 0x343e0000)
1751 return save_high21
+ extract_14 (inst
);
1753 /* fstws as used by the HP compilers. */
1754 if ((inst
& 0xffffffe0) == 0x2fd01220)
1755 return extract_5_load (inst
);
1757 /* No adjustment. */
1761 /* Return nonzero if INST is a branch of some kind, else return zero. */
1791 /* Return the register number for a GR which is saved by INST or
1792 zero it INST does not save a GR. */
1795 inst_saves_gr (inst
)
1798 /* Does it look like a stw? */
1799 if ((inst
>> 26) == 0x1a)
1800 return extract_5R_store (inst
);
1802 /* Does it look like a stwm? GCC & HPC may use this in prologues. */
1803 if ((inst
>> 26) == 0x1b)
1804 return extract_5R_store (inst
);
1806 /* Does it look like sth or stb? HPC versions 9.0 and later use these
1808 if ((inst
>> 26) == 0x19 || (inst
>> 26) == 0x18)
1809 return extract_5R_store (inst
);
1814 /* Return the register number for a FR which is saved by INST or
1815 zero it INST does not save a FR.
1817 Note we only care about full 64bit register stores (that's the only
1818 kind of stores the prologue will use).
1820 FIXME: What about argument stores with the HP compiler in ANSI mode? */
1823 inst_saves_fr (inst
)
1826 if ((inst
& 0xfc00dfc0) == 0x2c001200)
1827 return extract_5r_store (inst
);
1831 /* Advance PC across any function entry prologue instructions
1832 to reach some "real" code.
1834 Use information in the unwind table to determine what exactly should
1835 be in the prologue. */
1842 unsigned long inst
, stack_remaining
, save_gr
, save_fr
, save_rp
, save_sp
;
1843 unsigned long args_stored
, status
, i
;
1844 struct unwind_table_entry
*u
;
1846 u
= find_unwind_entry (pc
);
1850 /* If we are not at the beginning of a function, then return now. */
1851 if ((pc
& ~0x3) != u
->region_start
)
1854 /* This is how much of a frame adjustment we need to account for. */
1855 stack_remaining
= u
->Total_frame_size
<< 3;
1857 /* Magic register saves we want to know about. */
1858 save_rp
= u
->Save_RP
;
1859 save_sp
= u
->Save_SP
;
1861 /* An indication that args may be stored into the stack. Unfortunately
1862 the HPUX compilers tend to set this in cases where no args were
1864 args_stored
= u
->Args_stored
;
1866 /* Turn the Entry_GR field into a bitmask. */
1868 for (i
= 3; i
< u
->Entry_GR
+ 3; i
++)
1870 /* Frame pointer gets saved into a special location. */
1871 if (u
->Save_SP
&& i
== FP_REGNUM
)
1874 save_gr
|= (1 << i
);
1877 /* Turn the Entry_FR field into a bitmask too. */
1879 for (i
= 12; i
< u
->Entry_FR
+ 12; i
++)
1880 save_fr
|= (1 << i
);
1882 /* Loop until we find everything of interest or hit a branch.
1884 For unoptimized GCC code and for any HP CC code this will never ever
1885 examine any user instructions.
1887 For optimzied GCC code we're faced with problems. GCC will schedule
1888 its prologue and make prologue instructions available for delay slot
1889 filling. The end result is user code gets mixed in with the prologue
1890 and a prologue instruction may be in the delay slot of the first branch
1893 Some unexpected things are expected with debugging optimized code, so
1894 we allow this routine to walk past user instructions in optimized
1896 while (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0
1899 unsigned int reg_num
;
1900 unsigned long old_stack_remaining
, old_save_gr
, old_save_fr
;
1901 unsigned long old_save_rp
, old_save_sp
, old_args_stored
, next_inst
;
1903 /* Save copies of all the triggers so we can compare them later
1905 old_save_gr
= save_gr
;
1906 old_save_fr
= save_fr
;
1907 old_save_rp
= save_rp
;
1908 old_save_sp
= save_sp
;
1909 old_stack_remaining
= stack_remaining
;
1911 status
= target_read_memory (pc
, buf
, 4);
1912 inst
= extract_unsigned_integer (buf
, 4);
1918 /* Note the interesting effects of this instruction. */
1919 stack_remaining
-= prologue_inst_adjust_sp (inst
);
1921 /* There is only one instruction used for saving RP into the stack. */
1922 if (inst
== 0x6bc23fd9)
1925 /* This is the only way we save SP into the stack. At this time
1926 the HP compilers never bother to save SP into the stack. */
1927 if ((inst
& 0xffffc000) == 0x6fc10000)
1930 /* Account for general and floating-point register saves. */
1931 reg_num
= inst_saves_gr (inst
);
1932 save_gr
&= ~(1 << reg_num
);
1934 /* Ugh. Also account for argument stores into the stack.
1935 Unfortunately args_stored only tells us that some arguments
1936 where stored into the stack. Not how many or what kind!
1938 This is a kludge as on the HP compiler sets this bit and it
1939 never does prologue scheduling. So once we see one, skip past
1940 all of them. We have similar code for the fp arg stores below.
1942 FIXME. Can still die if we have a mix of GR and FR argument
1944 if (reg_num
>= 23 && reg_num
<= 26)
1946 while (reg_num
>= 23 && reg_num
<= 26)
1949 status
= target_read_memory (pc
, buf
, 4);
1950 inst
= extract_unsigned_integer (buf
, 4);
1953 reg_num
= inst_saves_gr (inst
);
1959 reg_num
= inst_saves_fr (inst
);
1960 save_fr
&= ~(1 << reg_num
);
1962 status
= target_read_memory (pc
+ 4, buf
, 4);
1963 next_inst
= extract_unsigned_integer (buf
, 4);
1969 /* We've got to be read to handle the ldo before the fp register
1971 if ((inst
& 0xfc000000) == 0x34000000
1972 && inst_saves_fr (next_inst
) >= 4
1973 && inst_saves_fr (next_inst
) <= 7)
1975 /* So we drop into the code below in a reasonable state. */
1976 reg_num
= inst_saves_fr (next_inst
);
1980 /* Ugh. Also account for argument stores into the stack.
1981 This is a kludge as on the HP compiler sets this bit and it
1982 never does prologue scheduling. So once we see one, skip past
1984 if (reg_num
>= 4 && reg_num
<= 7)
1986 while (reg_num
>= 4 && reg_num
<= 7)
1989 status
= target_read_memory (pc
, buf
, 4);
1990 inst
= extract_unsigned_integer (buf
, 4);
1993 if ((inst
& 0xfc000000) != 0x34000000)
1995 status
= target_read_memory (pc
+ 4, buf
, 4);
1996 next_inst
= extract_unsigned_integer (buf
, 4);
1999 reg_num
= inst_saves_fr (next_inst
);
2005 /* Quit if we hit any kind of branch. This can happen if a prologue
2006 instruction is in the delay slot of the first call/branch. */
2007 if (is_branch (inst
))
2010 /* What a crock. The HP compilers set args_stored even if no
2011 arguments were stored into the stack (boo hiss). This could
2012 cause this code to then skip a bunch of user insns (up to the
2015 To combat this we try to identify when args_stored was bogusly
2016 set and clear it. We only do this when args_stored is nonzero,
2017 all other resources are accounted for, and nothing changed on
2020 && ! (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0)
2021 && old_save_gr
== save_gr
&& old_save_fr
== save_fr
2022 && old_save_rp
== save_rp
&& old_save_sp
== save_sp
2023 && old_stack_remaining
== stack_remaining
)
2033 /* Put here the code to store, into a struct frame_saved_regs,
2034 the addresses of the saved registers of frame described by FRAME_INFO.
2035 This includes special registers such as pc and fp saved in special
2036 ways in the stack frame. sp is even more special:
2037 the address we return for it IS the sp for the next frame. */
2040 hppa_frame_find_saved_regs (frame_info
, frame_saved_regs
)
2041 struct frame_info
*frame_info
;
2042 struct frame_saved_regs
*frame_saved_regs
;
2045 struct unwind_table_entry
*u
;
2046 unsigned long inst
, stack_remaining
, save_gr
, save_fr
, save_rp
, save_sp
;
2051 /* Zero out everything. */
2052 memset (frame_saved_regs
, '\0', sizeof (struct frame_saved_regs
));
2054 /* Call dummy frames always look the same, so there's no need to
2055 examine the dummy code to determine locations of saved registers;
2056 instead, let find_dummy_frame_regs fill in the correct offsets
2057 for the saved registers. */
2058 if ((frame_info
->pc
>= frame_info
->frame
2059 && frame_info
->pc
<= (frame_info
->frame
+ CALL_DUMMY_LENGTH
2060 + 32 * 4 + (NUM_REGS
- FP0_REGNUM
) * 8
2062 find_dummy_frame_regs (frame_info
, frame_saved_regs
);
2064 /* Interrupt handlers are special too. They lay out the register
2065 state in the exact same order as the register numbers in GDB. */
2066 if (pc_in_interrupt_handler (frame_info
->pc
))
2068 for (i
= 0; i
< NUM_REGS
; i
++)
2070 /* SP is a little special. */
2072 frame_saved_regs
->regs
[SP_REGNUM
]
2073 = read_memory_integer (frame_info
->frame
+ SP_REGNUM
* 4, 4);
2075 frame_saved_regs
->regs
[i
] = frame_info
->frame
+ i
* 4;
2080 /* Handle signal handler callers. */
2081 if (frame_info
->signal_handler_caller
)
2083 FRAME_FIND_SAVED_REGS_IN_SIGTRAMP (frame_info
, frame_saved_regs
);
2087 /* Get the starting address of the function referred to by the PC
2089 pc
= get_pc_function_start (frame_info
->pc
);
2092 u
= find_unwind_entry (pc
);
2096 /* This is how much of a frame adjustment we need to account for. */
2097 stack_remaining
= u
->Total_frame_size
<< 3;
2099 /* Magic register saves we want to know about. */
2100 save_rp
= u
->Save_RP
;
2101 save_sp
= u
->Save_SP
;
2103 /* Turn the Entry_GR field into a bitmask. */
2105 for (i
= 3; i
< u
->Entry_GR
+ 3; i
++)
2107 /* Frame pointer gets saved into a special location. */
2108 if (u
->Save_SP
&& i
== FP_REGNUM
)
2111 save_gr
|= (1 << i
);
2114 /* Turn the Entry_FR field into a bitmask too. */
2116 for (i
= 12; i
< u
->Entry_FR
+ 12; i
++)
2117 save_fr
|= (1 << i
);
2119 /* The frame always represents the value of %sp at entry to the
2120 current function (and is thus equivalent to the "saved" stack
2122 frame_saved_regs
->regs
[SP_REGNUM
] = frame_info
->frame
;
2124 /* Loop until we find everything of interest or hit a branch.
2126 For unoptimized GCC code and for any HP CC code this will never ever
2127 examine any user instructions.
2129 For optimzied GCC code we're faced with problems. GCC will schedule
2130 its prologue and make prologue instructions available for delay slot
2131 filling. The end result is user code gets mixed in with the prologue
2132 and a prologue instruction may be in the delay slot of the first branch
2135 Some unexpected things are expected with debugging optimized code, so
2136 we allow this routine to walk past user instructions in optimized
2138 while (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0)
2140 status
= target_read_memory (pc
, buf
, 4);
2141 inst
= extract_unsigned_integer (buf
, 4);
2147 /* Note the interesting effects of this instruction. */
2148 stack_remaining
-= prologue_inst_adjust_sp (inst
);
2150 /* There is only one instruction used for saving RP into the stack. */
2151 if (inst
== 0x6bc23fd9)
2154 frame_saved_regs
->regs
[RP_REGNUM
] = frame_info
->frame
- 20;
2157 /* Just note that we found the save of SP into the stack. The
2158 value for frame_saved_regs was computed above. */
2159 if ((inst
& 0xffffc000) == 0x6fc10000)
2162 /* Account for general and floating-point register saves. */
2163 reg
= inst_saves_gr (inst
);
2164 if (reg
>= 3 && reg
<= 18
2165 && (!u
->Save_SP
|| reg
!= FP_REGNUM
))
2167 save_gr
&= ~(1 << reg
);
2169 /* stwm with a positive displacement is a *post modify*. */
2170 if ((inst
>> 26) == 0x1b
2171 && extract_14 (inst
) >= 0)
2172 frame_saved_regs
->regs
[reg
] = frame_info
->frame
;
2175 /* Handle code with and without frame pointers. */
2177 frame_saved_regs
->regs
[reg
]
2178 = frame_info
->frame
+ extract_14 (inst
);
2180 frame_saved_regs
->regs
[reg
]
2181 = frame_info
->frame
+ (u
->Total_frame_size
<< 3)
2182 + extract_14 (inst
);
2187 /* GCC handles callee saved FP regs a little differently.
2189 It emits an instruction to put the value of the start of
2190 the FP store area into %r1. It then uses fstds,ma with
2191 a basereg of %r1 for the stores.
2193 HP CC emits them at the current stack pointer modifying
2194 the stack pointer as it stores each register. */
2196 /* ldo X(%r3),%r1 or ldo X(%r30),%r1. */
2197 if ((inst
& 0xffffc000) == 0x34610000
2198 || (inst
& 0xffffc000) == 0x37c10000)
2199 fp_loc
= extract_14 (inst
);
2201 reg
= inst_saves_fr (inst
);
2202 if (reg
>= 12 && reg
<= 21)
2204 /* Note +4 braindamage below is necessary because the FP status
2205 registers are internally 8 registers rather than the expected
2207 save_fr
&= ~(1 << reg
);
2210 /* 1st HP CC FP register store. After this instruction
2211 we've set enough state that the GCC and HPCC code are
2212 both handled in the same manner. */
2213 frame_saved_regs
->regs
[reg
+ FP4_REGNUM
+ 4] = frame_info
->frame
;
2218 frame_saved_regs
->regs
[reg
+ FP0_REGNUM
+ 4]
2219 = frame_info
->frame
+ fp_loc
;
2224 /* Quit if we hit any kind of branch. This can happen if a prologue
2225 instruction is in the delay slot of the first call/branch. */
2226 if (is_branch (inst
))
2234 #ifdef MAINTENANCE_CMDS
2237 unwind_command (exp
, from_tty
)
2245 struct unwind_table_entry
*u
;
2248 /* If we have an expression, evaluate it and use it as the address. */
2250 if (exp
!= 0 && *exp
!= 0)
2251 address
= parse_and_eval_address (exp
);
2255 xxx
.u
= find_unwind_entry (address
);
2259 printf_unfiltered ("Can't find unwind table entry for PC 0x%x\n", address
);
2263 printf_unfiltered ("%08x\n%08X\n%08X\n%08X\n", xxx
.foo
[0], xxx
.foo
[1], xxx
.foo
[2],
2266 #endif /* MAINTENANCE_CMDS */
2269 _initialize_hppa_tdep ()
2271 #ifdef MAINTENANCE_CMDS
2272 add_cmd ("unwind", class_maintenance
, unwind_command
,
2273 "Print unwind table entry at given address.",
2274 &maintenanceprintlist
);
2275 #endif /* MAINTENANCE_CMDS */