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
, &saved_regs
);
789 if (read_memory_integer (saved_regs
.regs
[FLAGS_REGNUM
], 4) & 0x2)
790 pc
= read_memory_integer (saved_regs
.regs
[31], 4) & ~0x3;
792 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
795 pc
= read_register (ret_regnum
) & ~0x3;
802 rp_offset
= rp_saved (pc
);
803 /* Similar to code in frameless function case. If the next
804 frame is a signal or interrupt handler, then dig the right
805 information out of the saved register info. */
808 && (frame
->next
->signal_handler_caller
809 || pc_in_interrupt_handler (frame
->next
->pc
)))
811 struct frame_saved_regs saved_regs
;
813 get_frame_saved_regs (frame
->next
, &saved_regs
);
814 if (read_memory_integer (saved_regs
.regs
[FLAGS_REGNUM
], 4) & 0x2)
815 pc
= read_memory_integer (saved_regs
.regs
[31], 4) & ~0x3;
817 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
819 else if (rp_offset
== 0)
820 pc
= read_register (RP_REGNUM
) & ~0x3;
822 pc
= read_memory_integer (frame
->frame
+ rp_offset
, 4) & ~0x3;
825 /* If PC is inside a linker stub, then dig out the address the stub
827 u
= find_unwind_entry (pc
);
828 if (u
&& u
->stub_type
!= 0)
834 /* We need to correct the PC and the FP for the outermost frame when we are
838 init_extra_frame_info (fromleaf
, frame
)
840 struct frame_info
*frame
;
845 if (frame
->next
&& !fromleaf
)
848 /* If the next frame represents a frameless function invocation
849 then we have to do some adjustments that are normally done by
850 FRAME_CHAIN. (FRAME_CHAIN is not called in this case.) */
853 /* Find the framesize of *this* frame without peeking at the PC
854 in the current frame structure (it isn't set yet). */
855 framesize
= find_proc_framesize (FRAME_SAVED_PC (get_next_frame (frame
)));
857 /* Now adjust our base frame accordingly. If we have a frame pointer
858 use it, else subtract the size of this frame from the current
859 frame. (we always want frame->frame to point at the lowest address
862 frame
->frame
= read_register (FP_REGNUM
);
864 frame
->frame
-= framesize
;
868 flags
= read_register (FLAGS_REGNUM
);
869 if (flags
& 2) /* In system call? */
870 frame
->pc
= read_register (31) & ~0x3;
872 /* The outermost frame is always derived from PC-framesize
874 One might think frameless innermost frames should have
875 a frame->frame that is the same as the parent's frame->frame.
876 That is wrong; frame->frame in that case should be the *high*
877 address of the parent's frame. It's complicated as hell to
878 explain, but the parent *always* creates some stack space for
879 the child. So the child actually does have a frame of some
880 sorts, and its base is the high address in its parent's frame. */
881 framesize
= find_proc_framesize(frame
->pc
);
883 frame
->frame
= read_register (FP_REGNUM
);
885 frame
->frame
= read_register (SP_REGNUM
) - framesize
;
888 /* Given a GDB frame, determine the address of the calling function's frame.
889 This will be used to create a new GDB frame struct, and then
890 INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame.
892 This may involve searching through prologues for several functions
893 at boundaries where GCC calls HP C code, or where code which has
894 a frame pointer calls code without a frame pointer. */
898 struct frame_info
*frame
;
900 int my_framesize
, caller_framesize
;
901 struct unwind_table_entry
*u
;
902 CORE_ADDR frame_base
;
904 /* Handle HPUX, BSD, and OSF1 style interrupt frames first. These
905 are easy; at *sp we have a full save state strucutre which we can
906 pull the old stack pointer from. Also see frame_saved_pc for
907 code to dig a saved PC out of the save state structure. */
908 if (pc_in_interrupt_handler (frame
->pc
))
909 frame_base
= read_memory_integer (frame
->frame
+ SP_REGNUM
* 4, 4);
910 else if (frame
->signal_handler_caller
)
912 FRAME_BASE_BEFORE_SIGTRAMP (frame
, &frame_base
);
915 frame_base
= frame
->frame
;
917 /* Get frame sizes for the current frame and the frame of the
919 my_framesize
= find_proc_framesize (frame
->pc
);
920 caller_framesize
= find_proc_framesize (FRAME_SAVED_PC(frame
));
922 /* If caller does not have a frame pointer, then its frame
923 can be found at current_frame - caller_framesize. */
924 if (caller_framesize
!= -1)
925 return frame_base
- caller_framesize
;
927 /* Both caller and callee have frame pointers and are GCC compiled
928 (SAVE_SP bit in unwind descriptor is on for both functions.
929 The previous frame pointer is found at the top of the current frame. */
930 if (caller_framesize
== -1 && my_framesize
== -1)
931 return read_memory_integer (frame_base
, 4);
933 /* Caller has a frame pointer, but callee does not. This is a little
934 more difficult as GCC and HP C lay out locals and callee register save
935 areas very differently.
937 The previous frame pointer could be in a register, or in one of
938 several areas on the stack.
940 Walk from the current frame to the innermost frame examining
941 unwind descriptors to determine if %r3 ever gets saved into the
942 stack. If so return whatever value got saved into the stack.
943 If it was never saved in the stack, then the value in %r3 is still
946 We use information from unwind descriptors to determine if %r3
947 is saved into the stack (Entry_GR field has this information). */
951 u
= find_unwind_entry (frame
->pc
);
955 /* We could find this information by examining prologues. I don't
956 think anyone has actually written any tools (not even "strip")
957 which leave them out of an executable, so maybe this is a moot
959 warning ("Unable to find unwind for PC 0x%x -- Help!", frame
->pc
);
963 /* Entry_GR specifies the number of callee-saved general registers
964 saved in the stack. It starts at %r3, so %r3 would be 1. */
965 if (u
->Entry_GR
>= 1 || u
->Save_SP
966 || frame
->signal_handler_caller
967 || pc_in_interrupt_handler (frame
->pc
))
975 /* We may have walked down the chain into a function with a frame
978 && !frame
->signal_handler_caller
979 && !pc_in_interrupt_handler (frame
->pc
))
980 return read_memory_integer (frame
->frame
, 4);
981 /* %r3 was saved somewhere in the stack. Dig it out. */
984 struct frame_saved_regs saved_regs
;
986 get_frame_saved_regs (frame
, &saved_regs
);
987 return read_memory_integer (saved_regs
.regs
[FP_REGNUM
], 4);
992 /* The value in %r3 was never saved into the stack (thus %r3 still
993 holds the value of the previous frame pointer). */
994 return read_register (FP_REGNUM
);
999 /* To see if a frame chain is valid, see if the caller looks like it
1000 was compiled with gcc. */
1003 frame_chain_valid (chain
, thisframe
)
1005 struct frame_info
*thisframe
;
1007 struct minimal_symbol
*msym_us
;
1008 struct minimal_symbol
*msym_start
;
1009 struct unwind_table_entry
*u
, *next_u
= NULL
;
1010 struct frame_info
*next
;
1015 u
= find_unwind_entry (thisframe
->pc
);
1020 /* We can't just check that the same of msym_us is "_start", because
1021 someone idiotically decided that they were going to make a Ltext_end
1022 symbol with the same address. This Ltext_end symbol is totally
1023 indistinguishable (as nearly as I can tell) from the symbol for a function
1024 which is (legitimately, since it is in the user's namespace)
1025 named Ltext_end, so we can't just ignore it. */
1026 msym_us
= lookup_minimal_symbol_by_pc (FRAME_SAVED_PC (thisframe
));
1027 msym_start
= lookup_minimal_symbol ("_start", NULL
);
1030 && SYMBOL_VALUE_ADDRESS (msym_us
) == SYMBOL_VALUE_ADDRESS (msym_start
))
1033 next
= get_next_frame (thisframe
);
1035 next_u
= find_unwind_entry (next
->pc
);
1037 /* If this frame does not save SP, has no stack, isn't a stub,
1038 and doesn't "call" an interrupt routine or signal handler caller,
1039 then its not valid. */
1040 if (u
->Save_SP
|| u
->Total_frame_size
|| u
->stub_type
!= 0
1041 || (thisframe
->next
&& thisframe
->next
->signal_handler_caller
)
1042 || (next_u
&& next_u
->HP_UX_interrupt_marker
))
1045 if (pc_in_linker_stub (thisframe
->pc
))
1052 * These functions deal with saving and restoring register state
1053 * around a function call in the inferior. They keep the stack
1054 * double-word aligned; eventually, on an hp700, the stack will have
1055 * to be aligned to a 64-byte boundary.
1061 register CORE_ADDR sp
;
1062 register int regnum
;
1066 /* Space for "arguments"; the RP goes in here. */
1067 sp
= read_register (SP_REGNUM
) + 48;
1068 int_buffer
= read_register (RP_REGNUM
) | 0x3;
1069 write_memory (sp
- 20, (char *)&int_buffer
, 4);
1071 int_buffer
= read_register (FP_REGNUM
);
1072 write_memory (sp
, (char *)&int_buffer
, 4);
1074 write_register (FP_REGNUM
, sp
);
1078 for (regnum
= 1; regnum
< 32; regnum
++)
1079 if (regnum
!= RP_REGNUM
&& regnum
!= FP_REGNUM
)
1080 sp
= push_word (sp
, read_register (regnum
));
1084 for (regnum
= FP0_REGNUM
; regnum
< NUM_REGS
; regnum
++)
1086 read_register_bytes (REGISTER_BYTE (regnum
), (char *)&freg_buffer
, 8);
1087 sp
= push_bytes (sp
, (char *)&freg_buffer
, 8);
1089 sp
= push_word (sp
, read_register (IPSW_REGNUM
));
1090 sp
= push_word (sp
, read_register (SAR_REGNUM
));
1091 sp
= push_word (sp
, read_register (PCOQ_HEAD_REGNUM
));
1092 sp
= push_word (sp
, read_register (PCSQ_HEAD_REGNUM
));
1093 sp
= push_word (sp
, read_register (PCOQ_TAIL_REGNUM
));
1094 sp
= push_word (sp
, read_register (PCSQ_TAIL_REGNUM
));
1095 write_register (SP_REGNUM
, sp
);
1098 find_dummy_frame_regs (frame
, frame_saved_regs
)
1099 struct frame_info
*frame
;
1100 struct frame_saved_regs
*frame_saved_regs
;
1102 CORE_ADDR fp
= frame
->frame
;
1105 frame_saved_regs
->regs
[RP_REGNUM
] = fp
- 20 & ~0x3;
1106 frame_saved_regs
->regs
[FP_REGNUM
] = fp
;
1107 frame_saved_regs
->regs
[1] = fp
+ 8;
1109 for (fp
+= 12, i
= 3; i
< 32; i
++)
1113 frame_saved_regs
->regs
[i
] = fp
;
1119 for (i
= FP0_REGNUM
; i
< NUM_REGS
; i
++, fp
+= 8)
1120 frame_saved_regs
->regs
[i
] = fp
;
1122 frame_saved_regs
->regs
[IPSW_REGNUM
] = fp
;
1123 frame_saved_regs
->regs
[SAR_REGNUM
] = fp
+ 4;
1124 frame_saved_regs
->regs
[PCOQ_HEAD_REGNUM
] = fp
+ 8;
1125 frame_saved_regs
->regs
[PCSQ_HEAD_REGNUM
] = fp
+ 12;
1126 frame_saved_regs
->regs
[PCOQ_TAIL_REGNUM
] = fp
+ 16;
1127 frame_saved_regs
->regs
[PCSQ_TAIL_REGNUM
] = fp
+ 20;
1133 register struct frame_info
*frame
= get_current_frame ();
1134 register CORE_ADDR fp
;
1135 register int regnum
;
1136 struct frame_saved_regs fsr
;
1139 fp
= FRAME_FP (frame
);
1140 get_frame_saved_regs (frame
, &fsr
);
1142 #ifndef NO_PC_SPACE_QUEUE_RESTORE
1143 if (fsr
.regs
[IPSW_REGNUM
]) /* Restoring a call dummy frame */
1144 restore_pc_queue (&fsr
);
1147 for (regnum
= 31; regnum
> 0; regnum
--)
1148 if (fsr
.regs
[regnum
])
1149 write_register (regnum
, read_memory_integer (fsr
.regs
[regnum
], 4));
1151 for (regnum
= NUM_REGS
- 1; regnum
>= FP0_REGNUM
; regnum
--)
1152 if (fsr
.regs
[regnum
])
1154 read_memory (fsr
.regs
[regnum
], (char *)&freg_buffer
, 8);
1155 write_register_bytes (REGISTER_BYTE (regnum
), (char *)&freg_buffer
, 8);
1158 if (fsr
.regs
[IPSW_REGNUM
])
1159 write_register (IPSW_REGNUM
,
1160 read_memory_integer (fsr
.regs
[IPSW_REGNUM
], 4));
1162 if (fsr
.regs
[SAR_REGNUM
])
1163 write_register (SAR_REGNUM
,
1164 read_memory_integer (fsr
.regs
[SAR_REGNUM
], 4));
1166 /* If the PC was explicitly saved, then just restore it. */
1167 if (fsr
.regs
[PCOQ_TAIL_REGNUM
])
1168 write_register (PCOQ_TAIL_REGNUM
,
1169 read_memory_integer (fsr
.regs
[PCOQ_TAIL_REGNUM
], 4));
1171 /* Else use the value in %rp to set the new PC. */
1173 target_write_pc (read_register (RP_REGNUM
), 0);
1175 write_register (FP_REGNUM
, read_memory_integer (fp
, 4));
1177 if (fsr
.regs
[IPSW_REGNUM
]) /* call dummy */
1178 write_register (SP_REGNUM
, fp
- 48);
1180 write_register (SP_REGNUM
, fp
);
1182 flush_cached_frames ();
1186 * After returning to a dummy on the stack, restore the instruction
1187 * queue space registers. */
1190 restore_pc_queue (fsr
)
1191 struct frame_saved_regs
*fsr
;
1193 CORE_ADDR pc
= read_pc ();
1194 CORE_ADDR new_pc
= read_memory_integer (fsr
->regs
[PCOQ_HEAD_REGNUM
], 4);
1196 struct target_waitstatus w
;
1199 /* Advance past break instruction in the call dummy. */
1200 write_register (PCOQ_HEAD_REGNUM
, pc
+ 4);
1201 write_register (PCOQ_TAIL_REGNUM
, pc
+ 8);
1204 * HPUX doesn't let us set the space registers or the space
1205 * registers of the PC queue through ptrace. Boo, hiss.
1206 * Conveniently, the call dummy has this sequence of instructions
1211 * So, load up the registers and single step until we are in the
1215 write_register (21, read_memory_integer (fsr
->regs
[PCSQ_HEAD_REGNUM
], 4));
1216 write_register (22, new_pc
);
1218 for (insn_count
= 0; insn_count
< 3; insn_count
++)
1220 /* FIXME: What if the inferior gets a signal right now? Want to
1221 merge this into wait_for_inferior (as a special kind of
1222 watchpoint? By setting a breakpoint at the end? Is there
1223 any other choice? Is there *any* way to do this stuff with
1224 ptrace() or some equivalent?). */
1226 target_wait (inferior_pid
, &w
);
1228 if (w
.kind
== TARGET_WAITKIND_SIGNALLED
)
1230 stop_signal
= w
.value
.sig
;
1231 terminal_ours_for_output ();
1232 printf_unfiltered ("\nProgram terminated with signal %s, %s.\n",
1233 target_signal_to_name (stop_signal
),
1234 target_signal_to_string (stop_signal
));
1235 gdb_flush (gdb_stdout
);
1239 target_terminal_ours ();
1240 target_fetch_registers (-1);
1245 hppa_push_arguments (nargs
, args
, sp
, struct_return
, struct_addr
)
1250 CORE_ADDR struct_addr
;
1252 /* array of arguments' offsets */
1253 int *offset
= (int *)alloca(nargs
* sizeof (int));
1257 for (i
= 0; i
< nargs
; i
++)
1259 /* Coerce chars to int & float to double if necessary */
1260 args
[i
] = value_arg_coerce (args
[i
]);
1262 cum
+= TYPE_LENGTH (VALUE_TYPE (args
[i
]));
1264 /* value must go at proper alignment. Assume alignment is a
1266 alignment
= hppa_alignof (VALUE_TYPE (args
[i
]));
1267 if (cum
% alignment
)
1268 cum
= (cum
+ alignment
) & -alignment
;
1271 sp
+= max ((cum
+ 7) & -8, 16);
1273 for (i
= 0; i
< nargs
; i
++)
1274 write_memory (sp
+ offset
[i
], VALUE_CONTENTS (args
[i
]),
1275 TYPE_LENGTH (VALUE_TYPE (args
[i
])));
1278 write_register (28, struct_addr
);
1283 * Insert the specified number of args and function address
1284 * into a call sequence of the above form stored at DUMMYNAME.
1286 * On the hppa we need to call the stack dummy through $$dyncall.
1287 * Therefore our version of FIX_CALL_DUMMY takes an extra argument,
1288 * real_pc, which is the location where gdb should start up the
1289 * inferior to do the function call.
1293 hppa_fix_call_dummy (dummy
, pc
, fun
, nargs
, args
, type
, gcc_p
)
1302 CORE_ADDR dyncall_addr
, sr4export_addr
;
1303 struct minimal_symbol
*msymbol
;
1304 int flags
= read_register (FLAGS_REGNUM
);
1305 struct unwind_table_entry
*u
;
1307 msymbol
= lookup_minimal_symbol ("$$dyncall", (struct objfile
*) NULL
);
1308 if (msymbol
== NULL
)
1309 error ("Can't find an address for $$dyncall trampoline");
1311 dyncall_addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
1313 /* FUN could be a procedure label, in which case we have to get
1314 its real address and the value of its GOT/DP. */
1317 /* Get the GOT/DP value for the target function. It's
1318 at *(fun+4). Note the call dummy is *NOT* allowed to
1319 trash %r19 before calling the target function. */
1320 write_register (19, read_memory_integer ((fun
& ~0x3) + 4, 4));
1322 /* Now get the real address for the function we are calling, it's
1324 fun
= (CORE_ADDR
) read_memory_integer (fun
& ~0x3, 4);
1327 /* If we are calling an import stub (eg calling into a dynamic library)
1328 then have sr4export call the magic __d_plt_call routine which is linked
1329 in from end.o. (You can't use _sr4export to call the import stub as
1330 the value in sp-24 will get fried and you end up returning to the
1331 wrong location. You can't call the import stub directly as the code
1332 to bind the PLT entry to a function can't return to a stack address.) */
1333 u
= find_unwind_entry (fun
);
1334 if (u
&& u
->stub_type
== IMPORT
)
1337 msymbol
= lookup_minimal_symbol ("__d_plt_call", (struct objfile
*) NULL
);
1338 if (msymbol
== NULL
)
1339 error ("Can't find an address for __d_plt_call trampoline");
1341 /* This is where sr4export will jump to. */
1342 new_fun
= SYMBOL_VALUE_ADDRESS (msymbol
);
1344 /* We have to store the address of the stub in __shlib_funcptr. */
1345 msymbol
= lookup_minimal_symbol ("__shlib_funcptr",
1346 (struct objfile
*)NULL
);
1347 if (msymbol
== NULL
)
1348 error ("Can't find an address for __shlib_funcptr");
1350 target_write_memory (SYMBOL_VALUE_ADDRESS (msymbol
), (char *)&fun
, 4);
1355 /* We still need sr4export's address too. */
1356 msymbol
= lookup_minimal_symbol ("_sr4export", (struct objfile
*) NULL
);
1357 if (msymbol
== NULL
)
1358 error ("Can't find an address for _sr4export trampoline");
1360 sr4export_addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
1362 store_unsigned_integer
1363 (&dummy
[9*REGISTER_SIZE
],
1365 deposit_21 (fun
>> 11,
1366 extract_unsigned_integer (&dummy
[9*REGISTER_SIZE
],
1368 store_unsigned_integer
1369 (&dummy
[10*REGISTER_SIZE
],
1371 deposit_14 (fun
& MASK_11
,
1372 extract_unsigned_integer (&dummy
[10*REGISTER_SIZE
],
1374 store_unsigned_integer
1375 (&dummy
[12*REGISTER_SIZE
],
1377 deposit_21 (sr4export_addr
>> 11,
1378 extract_unsigned_integer (&dummy
[12*REGISTER_SIZE
],
1380 store_unsigned_integer
1381 (&dummy
[13*REGISTER_SIZE
],
1383 deposit_14 (sr4export_addr
& MASK_11
,
1384 extract_unsigned_integer (&dummy
[13*REGISTER_SIZE
],
1387 write_register (22, pc
);
1389 /* If we are in a syscall, then we should call the stack dummy
1390 directly. $$dyncall is not needed as the kernel sets up the
1391 space id registers properly based on the value in %r31. In
1392 fact calling $$dyncall will not work because the value in %r22
1393 will be clobbered on the syscall exit path. */
1397 return dyncall_addr
;
1401 /* Get the PC from %r31 if currently in a syscall. Also mask out privilege
1405 target_read_pc (pid
)
1408 int flags
= read_register (FLAGS_REGNUM
);
1411 return read_register (31) & ~0x3;
1412 return read_register (PC_REGNUM
) & ~0x3;
1415 /* Write out the PC. If currently in a syscall, then also write the new
1416 PC value into %r31. */
1419 target_write_pc (v
, pid
)
1423 int flags
= read_register (FLAGS_REGNUM
);
1425 /* If in a syscall, then set %r31. Also make sure to get the
1426 privilege bits set correctly. */
1428 write_register (31, (long) (v
| 0x3));
1430 write_register (PC_REGNUM
, (long) v
);
1431 write_register (NPC_REGNUM
, (long) v
+ 4);
1434 /* return the alignment of a type in bytes. Structures have the maximum
1435 alignment required by their fields. */
1441 int max_align
, align
, i
;
1442 switch (TYPE_CODE (arg
))
1447 return TYPE_LENGTH (arg
);
1448 case TYPE_CODE_ARRAY
:
1449 return hppa_alignof (TYPE_FIELD_TYPE (arg
, 0));
1450 case TYPE_CODE_STRUCT
:
1451 case TYPE_CODE_UNION
:
1453 for (i
= 0; i
< TYPE_NFIELDS (arg
); i
++)
1455 /* Bit fields have no real alignment. */
1456 if (!TYPE_FIELD_BITPOS (arg
, i
))
1458 align
= hppa_alignof (TYPE_FIELD_TYPE (arg
, i
));
1459 max_align
= max (max_align
, align
);
1468 /* Print the register regnum, or all registers if regnum is -1 */
1470 pa_do_registers_info (regnum
, fpregs
)
1474 char raw_regs
[REGISTER_BYTES
];
1477 for (i
= 0; i
< NUM_REGS
; i
++)
1478 read_relative_register_raw_bytes (i
, raw_regs
+ REGISTER_BYTE (i
));
1480 pa_print_registers (raw_regs
, regnum
, fpregs
);
1481 else if (regnum
< FP0_REGNUM
)
1482 printf_unfiltered ("%s %x\n", reg_names
[regnum
], *(long *)(raw_regs
+
1483 REGISTER_BYTE (regnum
)));
1485 pa_print_fp_reg (regnum
);
1488 pa_print_registers (raw_regs
, regnum
, fpregs
)
1495 for (i
= 0; i
< 18; i
++)
1496 printf_unfiltered ("%8.8s: %8x %8.8s: %8x %8.8s: %8x %8.8s: %8x\n",
1498 *(int *)(raw_regs
+ REGISTER_BYTE (i
)),
1500 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 18)),
1502 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 36)),
1504 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 54)));
1507 for (i
= 72; i
< NUM_REGS
; i
++)
1508 pa_print_fp_reg (i
);
1514 unsigned char raw_buffer
[MAX_REGISTER_RAW_SIZE
];
1515 unsigned char virtual_buffer
[MAX_REGISTER_VIRTUAL_SIZE
];
1517 /* Get 32bits of data. */
1518 read_relative_register_raw_bytes (i
, raw_buffer
);
1520 /* Put it in the buffer. No conversions are ever necessary. */
1521 memcpy (virtual_buffer
, raw_buffer
, REGISTER_RAW_SIZE (i
));
1523 fputs_filtered (reg_names
[i
], gdb_stdout
);
1524 print_spaces_filtered (8 - strlen (reg_names
[i
]), gdb_stdout
);
1525 fputs_filtered ("(single precision) ", gdb_stdout
);
1527 val_print (REGISTER_VIRTUAL_TYPE (i
), virtual_buffer
, 0, gdb_stdout
, 0,
1528 1, 0, Val_pretty_default
);
1529 printf_filtered ("\n");
1531 /* If "i" is even, then this register can also be a double-precision
1532 FP register. Dump it out as such. */
1535 /* Get the data in raw format for the 2nd half. */
1536 read_relative_register_raw_bytes (i
+ 1, raw_buffer
);
1538 /* Copy it into the appropriate part of the virtual buffer. */
1539 memcpy (virtual_buffer
+ REGISTER_RAW_SIZE (i
), raw_buffer
,
1540 REGISTER_RAW_SIZE (i
));
1542 /* Dump it as a double. */
1543 fputs_filtered (reg_names
[i
], gdb_stdout
);
1544 print_spaces_filtered (8 - strlen (reg_names
[i
]), gdb_stdout
);
1545 fputs_filtered ("(double precision) ", gdb_stdout
);
1547 val_print (builtin_type_double
, virtual_buffer
, 0, gdb_stdout
, 0,
1548 1, 0, Val_pretty_default
);
1549 printf_filtered ("\n");
1553 /* Figure out if PC is in a trampoline, and if so find out where
1554 the trampoline will jump to. If not in a trampoline, return zero.
1556 Simple code examination probably is not a good idea since the code
1557 sequences in trampolines can also appear in user code.
1559 We use unwinds and information from the minimal symbol table to
1560 determine when we're in a trampoline. This won't work for ELF
1561 (yet) since it doesn't create stub unwind entries. Whether or
1562 not ELF will create stub unwinds or normal unwinds for linker
1563 stubs is still being debated.
1565 This should handle simple calls through dyncall or sr4export,
1566 long calls, argument relocation stubs, and dyncall/sr4export
1567 calling an argument relocation stub. It even handles some stubs
1568 used in dynamic executables. */
1571 skip_trampoline_code (pc
, name
)
1576 long prev_inst
, curr_inst
, loc
;
1577 static CORE_ADDR dyncall
= 0;
1578 static CORE_ADDR sr4export
= 0;
1579 struct minimal_symbol
*msym
;
1580 struct unwind_table_entry
*u
;
1582 /* FIXME XXX - dyncall and sr4export must be initialized whenever we get a
1587 msym
= lookup_minimal_symbol ("$$dyncall", NULL
);
1589 dyncall
= SYMBOL_VALUE_ADDRESS (msym
);
1596 msym
= lookup_minimal_symbol ("_sr4export", NULL
);
1598 sr4export
= SYMBOL_VALUE_ADDRESS (msym
);
1603 /* Addresses passed to dyncall may *NOT* be the actual address
1604 of the function. So we may have to do something special. */
1607 pc
= (CORE_ADDR
) read_register (22);
1609 /* If bit 30 (counting from the left) is on, then pc is the address of
1610 the PLT entry for this function, not the address of the function
1611 itself. Bit 31 has meaning too, but only for MPE. */
1613 pc
= (CORE_ADDR
) read_memory_integer (pc
& ~0x3, 4);
1615 else if (pc
== sr4export
)
1616 pc
= (CORE_ADDR
) (read_register (22));
1618 /* Get the unwind descriptor corresponding to PC, return zero
1619 if no unwind was found. */
1620 u
= find_unwind_entry (pc
);
1624 /* If this isn't a linker stub, then return now. */
1625 if (u
->stub_type
== 0)
1626 return orig_pc
== pc
? 0 : pc
& ~0x3;
1628 /* It's a stub. Search for a branch and figure out where it goes.
1629 Note we have to handle multi insn branch sequences like ldil;ble.
1630 Most (all?) other branches can be determined by examining the contents
1631 of certain registers and the stack. */
1637 /* Make sure we haven't walked outside the range of this stub. */
1638 if (u
!= find_unwind_entry (loc
))
1640 warning ("Unable to find branch in linker stub");
1641 return orig_pc
== pc
? 0 : pc
& ~0x3;
1644 prev_inst
= curr_inst
;
1645 curr_inst
= read_memory_integer (loc
, 4);
1647 /* Does it look like a branch external using %r1? Then it's the
1648 branch from the stub to the actual function. */
1649 if ((curr_inst
& 0xffe0e000) == 0xe0202000)
1651 /* Yup. See if the previous instruction loaded
1652 a value into %r1. If so compute and return the jump address. */
1653 if ((prev_inst
& 0xffe00000) == 0x20200000)
1654 return (extract_21 (prev_inst
) + extract_17 (curr_inst
)) & ~0x3;
1657 warning ("Unable to find ldil X,%%r1 before ble Y(%%sr4,%%r1).");
1658 return orig_pc
== pc
? 0 : pc
& ~0x3;
1662 /* Does it look like bl X,%rp or bl X,%r0? Another way to do a
1663 branch from the stub to the actual function. */
1664 else if ((curr_inst
& 0xffe0e000) == 0xe8400000
1665 || (curr_inst
& 0xffe0e000) == 0xe8000000)
1666 return (loc
+ extract_17 (curr_inst
) + 8) & ~0x3;
1668 /* Does it look like bv (rp)? Note this depends on the
1669 current stack pointer being the same as the stack
1670 pointer in the stub itself! This is a branch on from the
1671 stub back to the original caller. */
1672 else if ((curr_inst
& 0xffe0e000) == 0xe840c000)
1674 /* Yup. See if the previous instruction loaded
1676 if (prev_inst
== 0x4bc23ff1)
1677 return (read_memory_integer
1678 (read_register (SP_REGNUM
) - 8, 4)) & ~0x3;
1681 warning ("Unable to find restore of %%rp before bv (%%rp).");
1682 return orig_pc
== pc
? 0 : pc
& ~0x3;
1686 /* What about be,n 0(sr0,%rp)? It's just another way we return to
1687 the original caller from the stub. Used in dynamic executables. */
1688 else if (curr_inst
== 0xe0400002)
1690 /* The value we jump to is sitting in sp - 24. But that's
1691 loaded several instructions before the be instruction.
1692 I guess we could check for the previous instruction being
1693 mtsp %r1,%sr0 if we want to do sanity checking. */
1694 return (read_memory_integer
1695 (read_register (SP_REGNUM
) - 24, 4)) & ~0x3;
1698 /* Haven't found the branch yet, but we're still in the stub.
1704 /* For the given instruction (INST), return any adjustment it makes
1705 to the stack pointer or zero for no adjustment.
1707 This only handles instructions commonly found in prologues. */
1710 prologue_inst_adjust_sp (inst
)
1713 /* This must persist across calls. */
1714 static int save_high21
;
1716 /* The most common way to perform a stack adjustment ldo X(sp),sp */
1717 if ((inst
& 0xffffc000) == 0x37de0000)
1718 return extract_14 (inst
);
1721 if ((inst
& 0xffe00000) == 0x6fc00000)
1722 return extract_14 (inst
);
1724 /* addil high21,%r1; ldo low11,(%r1),%r30)
1725 save high bits in save_high21 for later use. */
1726 if ((inst
& 0xffe00000) == 0x28200000)
1728 save_high21
= extract_21 (inst
);
1732 if ((inst
& 0xffff0000) == 0x343e0000)
1733 return save_high21
+ extract_14 (inst
);
1735 /* fstws as used by the HP compilers. */
1736 if ((inst
& 0xffffffe0) == 0x2fd01220)
1737 return extract_5_load (inst
);
1739 /* No adjustment. */
1743 /* Return nonzero if INST is a branch of some kind, else return zero. */
1773 /* Return the register number for a GR which is saved by INST or
1774 zero it INST does not save a GR. */
1777 inst_saves_gr (inst
)
1780 /* Does it look like a stw? */
1781 if ((inst
>> 26) == 0x1a)
1782 return extract_5R_store (inst
);
1784 /* Does it look like a stwm? GCC & HPC may use this in prologues. */
1785 if ((inst
>> 26) == 0x1b)
1786 return extract_5R_store (inst
);
1788 /* Does it look like sth or stb? HPC versions 9.0 and later use these
1790 if ((inst
>> 26) == 0x19 || (inst
>> 26) == 0x18)
1791 return extract_5R_store (inst
);
1796 /* Return the register number for a FR which is saved by INST or
1797 zero it INST does not save a FR.
1799 Note we only care about full 64bit register stores (that's the only
1800 kind of stores the prologue will use).
1802 FIXME: What about argument stores with the HP compiler in ANSI mode? */
1805 inst_saves_fr (inst
)
1808 if ((inst
& 0xfc00dfc0) == 0x2c001200)
1809 return extract_5r_store (inst
);
1813 /* Advance PC across any function entry prologue instructions
1814 to reach some "real" code.
1816 Use information in the unwind table to determine what exactly should
1817 be in the prologue. */
1824 unsigned long inst
, stack_remaining
, save_gr
, save_fr
, save_rp
, save_sp
;
1825 unsigned long args_stored
, status
, i
;
1826 struct unwind_table_entry
*u
;
1828 u
= find_unwind_entry (pc
);
1832 /* If we are not at the beginning of a function, then return now. */
1833 if ((pc
& ~0x3) != u
->region_start
)
1836 /* This is how much of a frame adjustment we need to account for. */
1837 stack_remaining
= u
->Total_frame_size
<< 3;
1839 /* Magic register saves we want to know about. */
1840 save_rp
= u
->Save_RP
;
1841 save_sp
= u
->Save_SP
;
1843 /* An indication that args may be stored into the stack. Unfortunately
1844 the HPUX compilers tend to set this in cases where no args were
1846 args_stored
= u
->Args_stored
;
1848 /* Turn the Entry_GR field into a bitmask. */
1850 for (i
= 3; i
< u
->Entry_GR
+ 3; i
++)
1852 /* Frame pointer gets saved into a special location. */
1853 if (u
->Save_SP
&& i
== FP_REGNUM
)
1856 save_gr
|= (1 << i
);
1859 /* Turn the Entry_FR field into a bitmask too. */
1861 for (i
= 12; i
< u
->Entry_FR
+ 12; i
++)
1862 save_fr
|= (1 << i
);
1864 /* Loop until we find everything of interest or hit a branch.
1866 For unoptimized GCC code and for any HP CC code this will never ever
1867 examine any user instructions.
1869 For optimzied GCC code we're faced with problems. GCC will schedule
1870 its prologue and make prologue instructions available for delay slot
1871 filling. The end result is user code gets mixed in with the prologue
1872 and a prologue instruction may be in the delay slot of the first branch
1875 Some unexpected things are expected with debugging optimized code, so
1876 we allow this routine to walk past user instructions in optimized
1878 while (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0
1881 unsigned int reg_num
;
1882 unsigned long old_stack_remaining
, old_save_gr
, old_save_fr
;
1883 unsigned long old_save_rp
, old_save_sp
, old_args_stored
, next_inst
;
1885 /* Save copies of all the triggers so we can compare them later
1887 old_save_gr
= save_gr
;
1888 old_save_fr
= save_fr
;
1889 old_save_rp
= save_rp
;
1890 old_save_sp
= save_sp
;
1891 old_stack_remaining
= stack_remaining
;
1893 status
= target_read_memory (pc
, buf
, 4);
1894 inst
= extract_unsigned_integer (buf
, 4);
1900 /* Note the interesting effects of this instruction. */
1901 stack_remaining
-= prologue_inst_adjust_sp (inst
);
1903 /* There is only one instruction used for saving RP into the stack. */
1904 if (inst
== 0x6bc23fd9)
1907 /* This is the only way we save SP into the stack. At this time
1908 the HP compilers never bother to save SP into the stack. */
1909 if ((inst
& 0xffffc000) == 0x6fc10000)
1912 /* Account for general and floating-point register saves. */
1913 reg_num
= inst_saves_gr (inst
);
1914 save_gr
&= ~(1 << reg_num
);
1916 /* Ugh. Also account for argument stores into the stack.
1917 Unfortunately args_stored only tells us that some arguments
1918 where stored into the stack. Not how many or what kind!
1920 This is a kludge as on the HP compiler sets this bit and it
1921 never does prologue scheduling. So once we see one, skip past
1922 all of them. We have similar code for the fp arg stores below.
1924 FIXME. Can still die if we have a mix of GR and FR argument
1926 if (reg_num
>= 23 && reg_num
<= 26)
1928 while (reg_num
>= 23 && reg_num
<= 26)
1931 status
= target_read_memory (pc
, buf
, 4);
1932 inst
= extract_unsigned_integer (buf
, 4);
1935 reg_num
= inst_saves_gr (inst
);
1941 reg_num
= inst_saves_fr (inst
);
1942 save_fr
&= ~(1 << reg_num
);
1944 status
= target_read_memory (pc
+ 4, buf
, 4);
1945 next_inst
= extract_unsigned_integer (buf
, 4);
1951 /* We've got to be read to handle the ldo before the fp register
1953 if ((inst
& 0xfc000000) == 0x34000000
1954 && inst_saves_fr (next_inst
) >= 4
1955 && inst_saves_fr (next_inst
) <= 7)
1957 /* So we drop into the code below in a reasonable state. */
1958 reg_num
= inst_saves_fr (next_inst
);
1962 /* Ugh. Also account for argument stores into the stack.
1963 This is a kludge as on the HP compiler sets this bit and it
1964 never does prologue scheduling. So once we see one, skip past
1966 if (reg_num
>= 4 && reg_num
<= 7)
1968 while (reg_num
>= 4 && reg_num
<= 7)
1971 status
= target_read_memory (pc
, buf
, 4);
1972 inst
= extract_unsigned_integer (buf
, 4);
1975 if ((inst
& 0xfc000000) != 0x34000000)
1977 status
= target_read_memory (pc
+ 4, buf
, 4);
1978 next_inst
= extract_unsigned_integer (buf
, 4);
1981 reg_num
= inst_saves_fr (next_inst
);
1987 /* Quit if we hit any kind of branch. This can happen if a prologue
1988 instruction is in the delay slot of the first call/branch. */
1989 if (is_branch (inst
))
1992 /* What a crock. The HP compilers set args_stored even if no
1993 arguments were stored into the stack (boo hiss). This could
1994 cause this code to then skip a bunch of user insns (up to the
1997 To combat this we try to identify when args_stored was bogusly
1998 set and clear it. We only do this when args_stored is nonzero,
1999 all other resources are accounted for, and nothing changed on
2002 && ! (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0)
2003 && old_save_gr
== save_gr
&& old_save_fr
== save_fr
2004 && old_save_rp
== save_rp
&& old_save_sp
== save_sp
2005 && old_stack_remaining
== stack_remaining
)
2015 /* Put here the code to store, into a struct frame_saved_regs,
2016 the addresses of the saved registers of frame described by FRAME_INFO.
2017 This includes special registers such as pc and fp saved in special
2018 ways in the stack frame. sp is even more special:
2019 the address we return for it IS the sp for the next frame. */
2022 hppa_frame_find_saved_regs (frame_info
, frame_saved_regs
)
2023 struct frame_info
*frame_info
;
2024 struct frame_saved_regs
*frame_saved_regs
;
2027 struct unwind_table_entry
*u
;
2028 unsigned long inst
, stack_remaining
, save_gr
, save_fr
, save_rp
, save_sp
;
2033 /* Zero out everything. */
2034 memset (frame_saved_regs
, '\0', sizeof (struct frame_saved_regs
));
2036 /* Call dummy frames always look the same, so there's no need to
2037 examine the dummy code to determine locations of saved registers;
2038 instead, let find_dummy_frame_regs fill in the correct offsets
2039 for the saved registers. */
2040 if ((frame_info
->pc
>= frame_info
->frame
2041 && frame_info
->pc
<= (frame_info
->frame
+ CALL_DUMMY_LENGTH
2042 + 32 * 4 + (NUM_REGS
- FP0_REGNUM
) * 8
2044 find_dummy_frame_regs (frame_info
, frame_saved_regs
);
2046 /* Interrupt handlers are special too. They lay out the register
2047 state in the exact same order as the register numbers in GDB. */
2048 if (pc_in_interrupt_handler (frame_info
->pc
))
2050 for (i
= 0; i
< NUM_REGS
; i
++)
2052 /* SP is a little special. */
2054 frame_saved_regs
->regs
[SP_REGNUM
]
2055 = read_memory_integer (frame_info
->frame
+ SP_REGNUM
* 4, 4);
2057 frame_saved_regs
->regs
[i
] = frame_info
->frame
+ i
* 4;
2062 /* Handle signal handler callers. */
2063 if (frame_info
->signal_handler_caller
)
2065 FRAME_FIND_SAVED_REGS_IN_SIGTRAMP (frame_info
, frame_saved_regs
);
2069 /* Get the starting address of the function referred to by the PC
2071 pc
= get_pc_function_start (frame_info
->pc
);
2074 u
= find_unwind_entry (pc
);
2078 /* This is how much of a frame adjustment we need to account for. */
2079 stack_remaining
= u
->Total_frame_size
<< 3;
2081 /* Magic register saves we want to know about. */
2082 save_rp
= u
->Save_RP
;
2083 save_sp
= u
->Save_SP
;
2085 /* Turn the Entry_GR field into a bitmask. */
2087 for (i
= 3; i
< u
->Entry_GR
+ 3; i
++)
2089 /* Frame pointer gets saved into a special location. */
2090 if (u
->Save_SP
&& i
== FP_REGNUM
)
2093 save_gr
|= (1 << i
);
2096 /* Turn the Entry_FR field into a bitmask too. */
2098 for (i
= 12; i
< u
->Entry_FR
+ 12; i
++)
2099 save_fr
|= (1 << i
);
2101 /* The frame always represents the value of %sp at entry to the
2102 current function (and is thus equivalent to the "saved" stack
2104 frame_saved_regs
->regs
[SP_REGNUM
] = frame_info
->frame
;
2106 /* Loop until we find everything of interest or hit a branch.
2108 For unoptimized GCC code and for any HP CC code this will never ever
2109 examine any user instructions.
2111 For optimzied GCC code we're faced with problems. GCC will schedule
2112 its prologue and make prologue instructions available for delay slot
2113 filling. The end result is user code gets mixed in with the prologue
2114 and a prologue instruction may be in the delay slot of the first branch
2117 Some unexpected things are expected with debugging optimized code, so
2118 we allow this routine to walk past user instructions in optimized
2120 while (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0)
2122 status
= target_read_memory (pc
, buf
, 4);
2123 inst
= extract_unsigned_integer (buf
, 4);
2129 /* Note the interesting effects of this instruction. */
2130 stack_remaining
-= prologue_inst_adjust_sp (inst
);
2132 /* There is only one instruction used for saving RP into the stack. */
2133 if (inst
== 0x6bc23fd9)
2136 frame_saved_regs
->regs
[RP_REGNUM
] = frame_info
->frame
- 20;
2139 /* Just note that we found the save of SP into the stack. The
2140 value for frame_saved_regs was computed above. */
2141 if ((inst
& 0xffffc000) == 0x6fc10000)
2144 /* Account for general and floating-point register saves. */
2145 reg
= inst_saves_gr (inst
);
2146 if (reg
>= 3 && reg
<= 18
2147 && (!u
->Save_SP
|| reg
!= FP_REGNUM
))
2149 save_gr
&= ~(1 << reg
);
2151 /* stwm with a positive displacement is a *post modify*. */
2152 if ((inst
>> 26) == 0x1b
2153 && extract_14 (inst
) >= 0)
2154 frame_saved_regs
->regs
[reg
] = frame_info
->frame
;
2157 /* Handle code with and without frame pointers. */
2159 frame_saved_regs
->regs
[reg
]
2160 = frame_info
->frame
+ extract_14 (inst
);
2162 frame_saved_regs
->regs
[reg
]
2163 = frame_info
->frame
+ (u
->Total_frame_size
<< 3)
2164 + extract_14 (inst
);
2169 /* GCC handles callee saved FP regs a little differently.
2171 It emits an instruction to put the value of the start of
2172 the FP store area into %r1. It then uses fstds,ma with
2173 a basereg of %r1 for the stores.
2175 HP CC emits them at the current stack pointer modifying
2176 the stack pointer as it stores each register. */
2178 /* ldo X(%r3),%r1 or ldo X(%r30),%r1. */
2179 if ((inst
& 0xffffc000) == 0x34610000
2180 || (inst
& 0xffffc000) == 0x37c10000)
2181 fp_loc
= extract_14 (inst
);
2183 reg
= inst_saves_fr (inst
);
2184 if (reg
>= 12 && reg
<= 21)
2186 /* Note +4 braindamage below is necessary because the FP status
2187 registers are internally 8 registers rather than the expected
2189 save_fr
&= ~(1 << reg
);
2192 /* 1st HP CC FP register store. After this instruction
2193 we've set enough state that the GCC and HPCC code are
2194 both handled in the same manner. */
2195 frame_saved_regs
->regs
[reg
+ FP4_REGNUM
+ 4] = frame_info
->frame
;
2200 frame_saved_regs
->regs
[reg
+ FP0_REGNUM
+ 4]
2201 = frame_info
->frame
+ fp_loc
;
2206 /* Quit if we hit any kind of branch. This can happen if a prologue
2207 instruction is in the delay slot of the first call/branch. */
2208 if (is_branch (inst
))
2216 #ifdef MAINTENANCE_CMDS
2219 unwind_command (exp
, from_tty
)
2227 struct unwind_table_entry
*u
;
2230 /* If we have an expression, evaluate it and use it as the address. */
2232 if (exp
!= 0 && *exp
!= 0)
2233 address
= parse_and_eval_address (exp
);
2237 xxx
.u
= find_unwind_entry (address
);
2241 printf_unfiltered ("Can't find unwind table entry for PC 0x%x\n", address
);
2245 printf_unfiltered ("%08x\n%08X\n%08X\n%08X\n", xxx
.foo
[0], xxx
.foo
[1], xxx
.foo
[2],
2248 #endif /* MAINTENANCE_CMDS */
2251 _initialize_hppa_tdep ()
2253 #ifdef MAINTENANCE_CMDS
2254 add_cmd ("unwind", class_maintenance
, unwind_command
,
2255 "Print unwind table entry at given address.",
2256 &maintenanceprintlist
);
2257 #endif /* MAINTENANCE_CMDS */