1 /* Machine-dependent code which would otherwise be in inflow.c and core.c,
2 for GDB, the GNU debugger. This code is for the HP PA-RISC cpu.
3 Copyright 1986, 1987, 1989, 1990, 1991, 1992, 1993 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>
39 #include <sys/ioctl.h>
41 #ifdef COFF_ENCAPSULATE
42 #include "a.out.encap.h"
47 #define N_SET_MAGIC(exec, val) ((exec).a_magic = (val))
50 /*#include <sys/user.h> After a.out.h */
53 #include <machine/psl.h>
62 static int restore_pc_queue
PARAMS ((struct frame_saved_regs
*fsr
));
63 static int hppa_alignof
PARAMS ((struct type
*arg
));
64 CORE_ADDR frame_saved_pc
PARAMS ((FRAME frame
));
65 static int prologue_inst_adjust_sp
PARAMS ((unsigned long));
66 static int is_branch
PARAMS ((unsigned long));
67 static int inst_saves_gr
PARAMS ((unsigned long));
68 static int inst_saves_fr
PARAMS ((unsigned long));
69 static int pc_in_interrupt_handler
PARAMS ((CORE_ADDR
));
70 static int pc_in_linker_stub
PARAMS ((CORE_ADDR
));
71 static int compare_unwind_entries
PARAMS ((struct unwind_table_entry
*,
72 struct unwind_table_entry
*));
73 static void read_unwind_info
PARAMS ((struct objfile
*));
74 static void internalize_unwinds
PARAMS ((struct objfile
*,
75 struct unwind_table_entry
*,
76 asection
*, unsigned int,
77 unsigned int, unsigned int *));
80 /* Routines to extract various sized constants out of hppa
83 /* This assumes that no garbage lies outside of the lower bits of
87 sign_extend (val
, bits
)
90 return (int)(val
>> bits
- 1 ? (-1 << bits
) | val
: val
);
93 /* For many immediate values the sign bit is the low bit! */
96 low_sign_extend (val
, bits
)
99 return (int)((val
& 0x1 ? (-1 << (bits
- 1)) : 0) | val
>> 1);
101 /* extract the immediate field from a ld{bhw}s instruction */
104 get_field (val
, from
, to
)
105 unsigned val
, from
, to
;
107 val
= val
>> 31 - to
;
108 return val
& ((1 << 32 - from
) - 1);
112 set_field (val
, from
, to
, new_val
)
113 unsigned *val
, from
, to
;
115 unsigned mask
= ~((1 << (to
- from
+ 1)) << (31 - from
));
116 return *val
= *val
& mask
| (new_val
<< (31 - from
));
119 /* extract a 3-bit space register number from a be, ble, mtsp or mfsp */
124 return GET_FIELD (word
, 18, 18) << 2 | GET_FIELD (word
, 16, 17);
127 extract_5_load (word
)
130 return low_sign_extend (word
>> 16 & MASK_5
, 5);
133 /* extract the immediate field from a st{bhw}s instruction */
136 extract_5_store (word
)
139 return low_sign_extend (word
& MASK_5
, 5);
142 /* extract the immediate field from a break instruction */
145 extract_5r_store (word
)
148 return (word
& MASK_5
);
151 /* extract the immediate field from a {sr}sm instruction */
154 extract_5R_store (word
)
157 return (word
>> 16 & MASK_5
);
160 /* extract an 11 bit immediate field */
166 return low_sign_extend (word
& MASK_11
, 11);
169 /* extract a 14 bit immediate field */
175 return low_sign_extend (word
& MASK_14
, 14);
178 /* deposit a 14 bit constant in a word */
181 deposit_14 (opnd
, word
)
185 unsigned sign
= (opnd
< 0 ? 1 : 0);
187 return word
| ((unsigned)opnd
<< 1 & MASK_14
) | sign
;
190 /* extract a 21 bit constant */
200 val
= GET_FIELD (word
, 20, 20);
202 val
|= GET_FIELD (word
, 9, 19);
204 val
|= GET_FIELD (word
, 5, 6);
206 val
|= GET_FIELD (word
, 0, 4);
208 val
|= GET_FIELD (word
, 7, 8);
209 return sign_extend (val
, 21) << 11;
212 /* deposit a 21 bit constant in a word. Although 21 bit constants are
213 usually the top 21 bits of a 32 bit constant, we assume that only
214 the low 21 bits of opnd are relevant */
217 deposit_21 (opnd
, word
)
222 val
|= GET_FIELD (opnd
, 11 + 14, 11 + 18);
224 val
|= GET_FIELD (opnd
, 11 + 12, 11 + 13);
226 val
|= GET_FIELD (opnd
, 11 + 19, 11 + 20);
228 val
|= GET_FIELD (opnd
, 11 + 1, 11 + 11);
230 val
|= GET_FIELD (opnd
, 11 + 0, 11 + 0);
234 /* extract a 12 bit constant from branch instructions */
240 return sign_extend (GET_FIELD (word
, 19, 28) |
241 GET_FIELD (word
, 29, 29) << 10 |
242 (word
& 0x1) << 11, 12) << 2;
245 /* extract a 17 bit constant from branch instructions, returning the
246 19 bit signed value. */
252 return sign_extend (GET_FIELD (word
, 19, 28) |
253 GET_FIELD (word
, 29, 29) << 10 |
254 GET_FIELD (word
, 11, 15) << 11 |
255 (word
& 0x1) << 16, 17) << 2;
259 /* Compare the start address for two unwind entries returning 1 if
260 the first address is larger than the second, -1 if the second is
261 larger than the first, and zero if they are equal. */
264 compare_unwind_entries (a
, b
)
265 struct unwind_table_entry
*a
;
266 struct unwind_table_entry
*b
;
268 if (a
->region_start
> b
->region_start
)
270 else if (a
->region_start
< b
->region_start
)
277 internalize_unwinds (objfile
, table
, section
, entries
, size
, indexp
)
278 struct objfile
*objfile
;
279 struct unwind_table_entry
*table
;
281 unsigned int entries
, size
;
282 unsigned int *indexp
;
284 /* We will read the unwind entries into temporary memory, then
285 fill in the actual unwind table. */
290 char *buf
= alloca (size
);
292 bfd_get_section_contents (objfile
->obfd
, section
, buf
, 0, size
);
294 /* Now internalize the information being careful to handle host/target
296 for (i
= 0; i
< entries
; i
++)
298 table
[i
].region_start
= bfd_get_32 (objfile
->obfd
,
301 table
[i
].region_end
= bfd_get_32 (objfile
->obfd
, (bfd_byte
*)buf
);
303 tmp
= bfd_get_32 (objfile
->obfd
, (bfd_byte
*)buf
);
305 table
[i
].Cannot_unwind
= (tmp
>> 31) & 0x1;;
306 table
[i
].Millicode
= (tmp
>> 30) & 0x1;
307 table
[i
].Millicode_save_sr0
= (tmp
>> 29) & 0x1;
308 table
[i
].Region_description
= (tmp
>> 27) & 0x3;
309 table
[i
].reserved1
= (tmp
>> 26) & 0x1;
310 table
[i
].Entry_SR
= (tmp
>> 25) & 0x1;
311 table
[i
].Entry_FR
= (tmp
>> 21) & 0xf;
312 table
[i
].Entry_GR
= (tmp
>> 16) & 0x1f;
313 table
[i
].Args_stored
= (tmp
>> 15) & 0x1;
314 table
[i
].Variable_Frame
= (tmp
>> 14) & 0x1;
315 table
[i
].Separate_Package_Body
= (tmp
>> 13) & 0x1;
316 table
[i
].Frame_Extension_Millicode
= (tmp
>> 12 ) & 0x1;
317 table
[i
].Stack_Overflow_Check
= (tmp
>> 11) & 0x1;
318 table
[i
].Two_Instruction_SP_Increment
= (tmp
>> 10) & 0x1;
319 table
[i
].Ada_Region
= (tmp
>> 9) & 0x1;
320 table
[i
].reserved2
= (tmp
>> 5) & 0xf;
321 table
[i
].Save_SP
= (tmp
>> 4) & 0x1;
322 table
[i
].Save_RP
= (tmp
>> 3) & 0x1;
323 table
[i
].Save_MRP_in_frame
= (tmp
>> 2) & 0x1;
324 table
[i
].extn_ptr_defined
= (tmp
>> 1) & 0x1;
325 table
[i
].Cleanup_defined
= tmp
& 0x1;
326 tmp
= bfd_get_32 (objfile
->obfd
, (bfd_byte
*)buf
);
328 table
[i
].MPE_XL_interrupt_marker
= (tmp
>> 31) & 0x1;
329 table
[i
].HP_UX_interrupt_marker
= (tmp
>> 30) & 0x1;
330 table
[i
].Large_frame
= (tmp
>> 29) & 0x1;
331 table
[i
].reserved4
= (tmp
>> 27) & 0x3;
332 table
[i
].Total_frame_size
= tmp
& 0x7ffffff;
337 /* Read in the backtrace information stored in the `$UNWIND_START$' section of
338 the object file. This info is used mainly by find_unwind_entry() to find
339 out the stack frame size and frame pointer used by procedures. We put
340 everything on the psymbol obstack in the objfile so that it automatically
341 gets freed when the objfile is destroyed. */
344 read_unwind_info (objfile
)
345 struct objfile
*objfile
;
347 asection
*unwind_sec
, *elf_unwind_sec
, *stub_unwind_sec
;
348 unsigned unwind_size
, elf_unwind_size
, stub_unwind_size
, total_size
;
349 unsigned index
, unwind_entries
, elf_unwind_entries
;
350 unsigned stub_entries
, total_entries
;
351 struct obj_unwind_info
*ui
;
353 ui
= obstack_alloc (&objfile
->psymbol_obstack
,
354 sizeof (struct obj_unwind_info
));
360 /* Get hooks to all unwind sections. Note there is no linker-stub unwind
361 section in ELF at the moment. */
362 unwind_sec
= bfd_get_section_by_name (objfile
->obfd
, "$UNWIND_START$");
363 elf_unwind_sec
= bfd_get_section_by_name (objfile
->obfd
, ".hppa_unwind");
364 stub_unwind_sec
= bfd_get_section_by_name (objfile
->obfd
, "$UNWIND_END$");
366 /* Get sizes and unwind counts for all sections. */
369 unwind_size
= bfd_section_size (objfile
->obfd
, unwind_sec
);
370 unwind_entries
= unwind_size
/ UNWIND_ENTRY_SIZE
;
380 elf_unwind_size
= bfd_section_size (objfile
->obfd
, elf_unwind_sec
);
381 elf_unwind_entries
= elf_unwind_size
/ UNWIND_ENTRY_SIZE
;
386 stub_unwind_size
= bfd_section_size (objfile
->obfd
, stub_unwind_sec
);
387 stub_entries
= stub_unwind_size
/ STUB_UNWIND_ENTRY_SIZE
;
391 stub_unwind_size
= 0;
395 /* Compute total number of unwind entries and their total size. */
396 total_entries
= unwind_entries
+ elf_unwind_entries
+ stub_entries
;
397 total_size
= total_entries
* sizeof (struct unwind_table_entry
);
399 /* Allocate memory for the unwind table. */
400 ui
->table
= obstack_alloc (&objfile
->psymbol_obstack
, total_size
);
401 ui
->last
= total_entries
- 1;
403 /* Internalize the standard unwind entries. */
405 internalize_unwinds (objfile
, &ui
->table
[index
], unwind_sec
,
406 unwind_entries
, unwind_size
);
407 index
+= unwind_entries
;
408 internalize_unwinds (objfile
, &ui
->table
[index
], elf_unwind_sec
,
409 elf_unwind_entries
, elf_unwind_size
);
410 index
+= elf_unwind_entries
;
412 /* Now internalize the stub unwind entries. */
413 if (stub_unwind_size
> 0)
416 char *buf
= alloca (stub_unwind_size
);
418 /* Read in the stub unwind entries. */
419 bfd_get_section_contents (objfile
->obfd
, stub_unwind_sec
, buf
,
420 0, stub_unwind_size
);
422 /* Now convert them into regular unwind entries. */
423 for (i
= 0; i
< stub_entries
; i
++, index
++)
425 /* Clear out the next unwind entry. */
426 memset (&ui
->table
[index
], 0, sizeof (struct unwind_table_entry
));
428 /* Convert offset & size into region_start and region_end.
429 Stuff away the stub type into "reserved" fields. */
430 ui
->table
[index
].region_start
= bfd_get_32 (objfile
->obfd
,
433 ui
->table
[index
].stub_type
= bfd_get_8 (objfile
->obfd
,
436 ui
->table
[index
].region_end
437 = ui
->table
[index
].region_start
+ 4 *
438 (bfd_get_16 (objfile
->obfd
, (bfd_byte
*) buf
) - 1);
444 /* Unwind table needs to be kept sorted. */
445 qsort (ui
->table
, total_entries
, sizeof (struct unwind_table_entry
),
446 compare_unwind_entries
);
448 /* Keep a pointer to the unwind information. */
449 objfile
->obj_private
= (PTR
) ui
;
452 /* Lookup the unwind (stack backtrace) info for the given PC. We search all
453 of the objfiles seeking the unwind table entry for this PC. Each objfile
454 contains a sorted list of struct unwind_table_entry. Since we do a binary
455 search of the unwind tables, we depend upon them to be sorted. */
457 static struct unwind_table_entry
*
458 find_unwind_entry(pc
)
461 int first
, middle
, last
;
462 struct objfile
*objfile
;
464 ALL_OBJFILES (objfile
)
466 struct obj_unwind_info
*ui
;
468 ui
= OBJ_UNWIND_INFO (objfile
);
472 read_unwind_info (objfile
);
473 ui
= OBJ_UNWIND_INFO (objfile
);
476 /* First, check the cache */
479 && pc
>= ui
->cache
->region_start
480 && pc
<= ui
->cache
->region_end
)
483 /* Not in the cache, do a binary search */
488 while (first
<= last
)
490 middle
= (first
+ last
) / 2;
491 if (pc
>= ui
->table
[middle
].region_start
492 && pc
<= ui
->table
[middle
].region_end
)
494 ui
->cache
= &ui
->table
[middle
];
495 return &ui
->table
[middle
];
498 if (pc
< ui
->table
[middle
].region_start
)
503 } /* ALL_OBJFILES() */
507 /* Called to determine if PC is in an interrupt handler of some
511 pc_in_interrupt_handler (pc
)
514 struct unwind_table_entry
*u
;
515 struct minimal_symbol
*msym_us
;
517 u
= find_unwind_entry (pc
);
521 /* Oh joys. HPUX sets the interrupt bit for _sigreturn even though
522 its frame isn't a pure interrupt frame. Deal with this. */
523 msym_us
= lookup_minimal_symbol_by_pc (pc
);
525 return u
->HP_UX_interrupt_marker
&& !IN_SIGTRAMP (pc
, SYMBOL_NAME (msym_us
));
528 /* Called when no unwind descriptor was found for PC. Returns 1 if it
529 appears that PC is in a linker stub. */
532 pc_in_linker_stub (pc
)
535 int found_magic_instruction
= 0;
539 /* If unable to read memory, assume pc is not in a linker stub. */
540 if (target_read_memory (pc
, buf
, 4) != 0)
543 /* We are looking for something like
545 ; $$dyncall jams RP into this special spot in the frame (RP')
546 ; before calling the "call stub"
549 ldsid (rp),r1 ; Get space associated with RP into r1
550 mtsp r1,sp ; Move it into space register 0
551 be,n 0(sr0),rp) ; back to your regularly scheduled program
554 /* Maximum known linker stub size is 4 instructions. Search forward
555 from the given PC, then backward. */
556 for (i
= 0; i
< 4; i
++)
558 /* If we hit something with an unwind, stop searching this direction. */
560 if (find_unwind_entry (pc
+ i
* 4) != 0)
563 /* Check for ldsid (rp),r1 which is the magic instruction for a
564 return from a cross-space function call. */
565 if (read_memory_integer (pc
+ i
* 4, 4) == 0x004010a1)
567 found_magic_instruction
= 1;
570 /* Add code to handle long call/branch and argument relocation stubs
574 if (found_magic_instruction
!= 0)
577 /* Now look backward. */
578 for (i
= 0; i
< 4; i
++)
580 /* If we hit something with an unwind, stop searching this direction. */
582 if (find_unwind_entry (pc
- i
* 4) != 0)
585 /* Check for ldsid (rp),r1 which is the magic instruction for a
586 return from a cross-space function call. */
587 if (read_memory_integer (pc
- i
* 4, 4) == 0x004010a1)
589 found_magic_instruction
= 1;
592 /* Add code to handle long call/branch and argument relocation stubs
595 return found_magic_instruction
;
599 find_return_regnum(pc
)
602 struct unwind_table_entry
*u
;
604 u
= find_unwind_entry (pc
);
615 /* Return size of frame, or -1 if we should use a frame pointer. */
617 find_proc_framesize (pc
)
620 struct unwind_table_entry
*u
;
621 struct minimal_symbol
*msym_us
;
623 u
= find_unwind_entry (pc
);
627 if (pc_in_linker_stub (pc
))
628 /* Linker stubs have a zero size frame. */
634 msym_us
= lookup_minimal_symbol_by_pc (pc
);
636 /* If Save_SP is set, and we're not in an interrupt or signal caller,
637 then we have a frame pointer. Use it. */
638 if (u
->Save_SP
&& !pc_in_interrupt_handler (pc
)
639 && !IN_SIGTRAMP (pc
, SYMBOL_NAME (msym_us
)))
642 return u
->Total_frame_size
<< 3;
645 /* Return offset from sp at which rp is saved, or 0 if not saved. */
646 static int rp_saved
PARAMS ((CORE_ADDR
));
652 struct unwind_table_entry
*u
;
654 u
= find_unwind_entry (pc
);
658 if (pc_in_linker_stub (pc
))
659 /* This is the so-called RP'. */
667 else if (u
->stub_type
!= 0)
669 switch (u
->stub_type
)
673 case PARAMETER_RELOCATION
:
684 frameless_function_invocation (frame
)
687 struct unwind_table_entry
*u
;
689 u
= find_unwind_entry (frame
->pc
);
694 return (u
->Total_frame_size
== 0 && u
->stub_type
== 0);
698 saved_pc_after_call (frame
)
703 ret_regnum
= find_return_regnum (get_frame_pc (frame
));
705 return read_register (ret_regnum
) & ~0x3;
709 frame_saved_pc (frame
)
712 CORE_ADDR pc
= get_frame_pc (frame
);
713 struct unwind_table_entry
*u
;
715 /* BSD, HPUX & OSF1 all lay out the hardware state in the same manner
716 at the base of the frame in an interrupt handler. Registers within
717 are saved in the exact same order as GDB numbers registers. How
719 if (pc_in_interrupt_handler (pc
))
720 return read_memory_integer (frame
->frame
+ PC_REGNUM
* 4, 4) & ~0x3;
722 /* Deal with signal handler caller frames too. */
723 if (frame
->signal_handler_caller
)
726 FRAME_SAVED_PC_IN_SIGTRAMP (frame
, &rp
);
731 if (frameless_function_invocation (frame
))
735 ret_regnum
= find_return_regnum (pc
);
737 /* If the next frame is an interrupt frame or a signal
738 handler caller, then we need to look in the saved
739 register area to get the return pointer (the values
740 in the registers may not correspond to anything useful). */
742 && (frame
->next
->signal_handler_caller
743 || pc_in_interrupt_handler (frame
->next
->pc
)))
745 struct frame_info
*fi
;
746 struct frame_saved_regs saved_regs
;
748 fi
= get_frame_info (frame
->next
);
749 get_frame_saved_regs (fi
, &saved_regs
);
750 if (read_memory_integer (saved_regs
.regs
[FLAGS_REGNUM
] & 0x2, 4))
751 pc
= read_memory_integer (saved_regs
.regs
[31], 4) & ~0x3;
753 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
756 pc
= read_register (ret_regnum
) & ~0x3;
760 int rp_offset
= rp_saved (pc
);
762 /* Similar to code in frameless function case. If the next
763 frame is a signal or interrupt handler, then dig the right
764 information out of the saved register info. */
767 && (frame
->next
->signal_handler_caller
768 || pc_in_interrupt_handler (frame
->next
->pc
)))
770 struct frame_info
*fi
;
771 struct frame_saved_regs saved_regs
;
773 fi
= get_frame_info (frame
->next
);
774 get_frame_saved_regs (fi
, &saved_regs
);
775 if (read_memory_integer (saved_regs
.regs
[FLAGS_REGNUM
] & 0x2, 4))
776 pc
= read_memory_integer (saved_regs
.regs
[31], 4) & ~0x3;
778 pc
= read_memory_integer (saved_regs
.regs
[RP_REGNUM
], 4) & ~0x3;
780 else if (rp_offset
== 0)
781 pc
= read_register (RP_REGNUM
) & ~0x3;
783 pc
= read_memory_integer (frame
->frame
+ rp_offset
, 4) & ~0x3;
786 /* If PC is inside a linker stub, then dig out the address the stub
788 u
= find_unwind_entry (pc
);
789 if (u
&& u
->stub_type
!= 0)
795 /* We need to correct the PC and the FP for the outermost frame when we are
799 init_extra_frame_info (fromleaf
, frame
)
801 struct frame_info
*frame
;
806 if (frame
->next
&& !fromleaf
)
809 /* If the next frame represents a frameless function invocation
810 then we have to do some adjustments that are normally done by
811 FRAME_CHAIN. (FRAME_CHAIN is not called in this case.) */
814 /* Find the framesize of *this* frame without peeking at the PC
815 in the current frame structure (it isn't set yet). */
816 framesize
= find_proc_framesize (FRAME_SAVED_PC (get_next_frame (frame
)));
818 /* Now adjust our base frame accordingly. If we have a frame pointer
819 use it, else subtract the size of this frame from the current
820 frame. (we always want frame->frame to point at the lowest address
823 frame
->frame
= read_register (FP_REGNUM
);
825 frame
->frame
-= framesize
;
829 flags
= read_register (FLAGS_REGNUM
);
830 if (flags
& 2) /* In system call? */
831 frame
->pc
= read_register (31) & ~0x3;
833 /* The outermost frame is always derived from PC-framesize
835 One might think frameless innermost frames should have
836 a frame->frame that is the same as the parent's frame->frame.
837 That is wrong; frame->frame in that case should be the *high*
838 address of the parent's frame. It's complicated as hell to
839 explain, but the parent *always* creates some stack space for
840 the child. So the child actually does have a frame of some
841 sorts, and its base is the high address in its parent's frame. */
842 framesize
= find_proc_framesize(frame
->pc
);
844 frame
->frame
= read_register (FP_REGNUM
);
846 frame
->frame
= read_register (SP_REGNUM
) - framesize
;
849 /* Given a GDB frame, determine the address of the calling function's frame.
850 This will be used to create a new GDB frame struct, and then
851 INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame.
853 This may involve searching through prologues for several functions
854 at boundaries where GCC calls HP C code, or where code which has
855 a frame pointer calls code without a frame pointer. */
860 struct frame_info
*frame
;
862 int my_framesize
, caller_framesize
;
863 struct unwind_table_entry
*u
;
864 CORE_ADDR frame_base
;
866 /* Handle HPUX, BSD, and OSF1 style interrupt frames first. These
867 are easy; at *sp we have a full save state strucutre which we can
868 pull the old stack pointer from. Also see frame_saved_pc for
869 code to dig a saved PC out of the save state structure. */
870 if (pc_in_interrupt_handler (frame
->pc
))
871 frame_base
= read_memory_integer (frame
->frame
+ SP_REGNUM
* 4, 4);
872 else if (frame
->signal_handler_caller
)
874 FRAME_BASE_BEFORE_SIGTRAMP (frame
, &frame_base
);
877 frame_base
= frame
->frame
;
879 /* Get frame sizes for the current frame and the frame of the
881 my_framesize
= find_proc_framesize (frame
->pc
);
882 caller_framesize
= find_proc_framesize (FRAME_SAVED_PC(frame
));
884 /* If caller does not have a frame pointer, then its frame
885 can be found at current_frame - caller_framesize. */
886 if (caller_framesize
!= -1)
887 return frame_base
- caller_framesize
;
889 /* Both caller and callee have frame pointers and are GCC compiled
890 (SAVE_SP bit in unwind descriptor is on for both functions.
891 The previous frame pointer is found at the top of the current frame. */
892 if (caller_framesize
== -1 && my_framesize
== -1)
893 return read_memory_integer (frame_base
, 4);
895 /* Caller has a frame pointer, but callee does not. This is a little
896 more difficult as GCC and HP C lay out locals and callee register save
897 areas very differently.
899 The previous frame pointer could be in a register, or in one of
900 several areas on the stack.
902 Walk from the current frame to the innermost frame examining
903 unwind descriptors to determine if %r3 ever gets saved into the
904 stack. If so return whatever value got saved into the stack.
905 If it was never saved in the stack, then the value in %r3 is still
908 We use information from unwind descriptors to determine if %r3
909 is saved into the stack (Entry_GR field has this information). */
913 u
= find_unwind_entry (frame
->pc
);
917 /* We could find this information by examining prologues. I don't
918 think anyone has actually written any tools (not even "strip")
919 which leave them out of an executable, so maybe this is a moot
921 warning ("Unable to find unwind for PC 0x%x -- Help!", frame
->pc
);
925 /* Entry_GR specifies the number of callee-saved general registers
926 saved in the stack. It starts at %r3, so %r3 would be 1. */
927 if (u
->Entry_GR
>= 1 || u
->Save_SP
928 || frame
->signal_handler_caller
929 || pc_in_interrupt_handler (frame
->pc
))
937 /* We may have walked down the chain into a function with a frame
940 && !frame
->signal_handler_caller
941 && !pc_in_interrupt_handler (frame
->pc
))
942 return read_memory_integer (frame
->frame
, 4);
943 /* %r3 was saved somewhere in the stack. Dig it out. */
946 struct frame_info
*fi
;
947 struct frame_saved_regs saved_regs
;
949 fi
= get_frame_info (frame
);
950 get_frame_saved_regs (fi
, &saved_regs
);
951 return read_memory_integer (saved_regs
.regs
[FP_REGNUM
], 4);
956 /* The value in %r3 was never saved into the stack (thus %r3 still
957 holds the value of the previous frame pointer). */
958 return read_register (FP_REGNUM
);
963 /* To see if a frame chain is valid, see if the caller looks like it
964 was compiled with gcc. */
967 frame_chain_valid (chain
, thisframe
)
971 struct minimal_symbol
*msym_us
;
972 struct minimal_symbol
*msym_start
;
973 struct unwind_table_entry
*u
, *next_u
= NULL
;
979 u
= find_unwind_entry (thisframe
->pc
);
984 /* We can't just check that the same of msym_us is "_start", because
985 someone idiotically decided that they were going to make a Ltext_end
986 symbol with the same address. This Ltext_end symbol is totally
987 indistinguishable (as nearly as I can tell) from the symbol for a function
988 which is (legitimately, since it is in the user's namespace)
989 named Ltext_end, so we can't just ignore it. */
990 msym_us
= lookup_minimal_symbol_by_pc (FRAME_SAVED_PC (thisframe
));
991 msym_start
= lookup_minimal_symbol ("_start", NULL
);
994 && SYMBOL_VALUE_ADDRESS (msym_us
) == SYMBOL_VALUE_ADDRESS (msym_start
))
997 next
= get_next_frame (thisframe
);
999 next_u
= find_unwind_entry (next
->pc
);
1001 /* If this frame does not save SP, has no stack, isn't a stub,
1002 and doesn't "call" an interrupt routine or signal handler caller,
1003 then its not valid. */
1004 if (u
->Save_SP
|| u
->Total_frame_size
|| u
->stub_type
!= 0
1005 || (thisframe
->next
&& thisframe
->next
->signal_handler_caller
)
1006 || (next_u
&& next_u
->HP_UX_interrupt_marker
))
1009 if (pc_in_linker_stub (thisframe
->pc
))
1016 * These functions deal with saving and restoring register state
1017 * around a function call in the inferior. They keep the stack
1018 * double-word aligned; eventually, on an hp700, the stack will have
1019 * to be aligned to a 64-byte boundary.
1025 register CORE_ADDR sp
;
1026 register int regnum
;
1030 /* Space for "arguments"; the RP goes in here. */
1031 sp
= read_register (SP_REGNUM
) + 48;
1032 int_buffer
= read_register (RP_REGNUM
) | 0x3;
1033 write_memory (sp
- 20, (char *)&int_buffer
, 4);
1035 int_buffer
= read_register (FP_REGNUM
);
1036 write_memory (sp
, (char *)&int_buffer
, 4);
1038 write_register (FP_REGNUM
, sp
);
1042 for (regnum
= 1; regnum
< 32; regnum
++)
1043 if (regnum
!= RP_REGNUM
&& regnum
!= FP_REGNUM
)
1044 sp
= push_word (sp
, read_register (regnum
));
1048 for (regnum
= FP0_REGNUM
; regnum
< NUM_REGS
; regnum
++)
1050 read_register_bytes (REGISTER_BYTE (regnum
), (char *)&freg_buffer
, 8);
1051 sp
= push_bytes (sp
, (char *)&freg_buffer
, 8);
1053 sp
= push_word (sp
, read_register (IPSW_REGNUM
));
1054 sp
= push_word (sp
, read_register (SAR_REGNUM
));
1055 sp
= push_word (sp
, read_register (PCOQ_HEAD_REGNUM
));
1056 sp
= push_word (sp
, read_register (PCSQ_HEAD_REGNUM
));
1057 sp
= push_word (sp
, read_register (PCOQ_TAIL_REGNUM
));
1058 sp
= push_word (sp
, read_register (PCSQ_TAIL_REGNUM
));
1059 write_register (SP_REGNUM
, sp
);
1062 find_dummy_frame_regs (frame
, frame_saved_regs
)
1063 struct frame_info
*frame
;
1064 struct frame_saved_regs
*frame_saved_regs
;
1066 CORE_ADDR fp
= frame
->frame
;
1069 frame_saved_regs
->regs
[RP_REGNUM
] = fp
- 20 & ~0x3;
1070 frame_saved_regs
->regs
[FP_REGNUM
] = fp
;
1071 frame_saved_regs
->regs
[1] = fp
+ 8;
1073 for (fp
+= 12, i
= 3; i
< 32; i
++)
1077 frame_saved_regs
->regs
[i
] = fp
;
1083 for (i
= FP0_REGNUM
; i
< NUM_REGS
; i
++, fp
+= 8)
1084 frame_saved_regs
->regs
[i
] = fp
;
1086 frame_saved_regs
->regs
[IPSW_REGNUM
] = fp
;
1087 frame_saved_regs
->regs
[SAR_REGNUM
] = fp
+ 4;
1088 frame_saved_regs
->regs
[PCOQ_HEAD_REGNUM
] = fp
+ 8;
1089 frame_saved_regs
->regs
[PCSQ_HEAD_REGNUM
] = fp
+ 12;
1090 frame_saved_regs
->regs
[PCOQ_TAIL_REGNUM
] = fp
+ 16;
1091 frame_saved_regs
->regs
[PCSQ_TAIL_REGNUM
] = fp
+ 20;
1097 register FRAME frame
= get_current_frame ();
1098 register CORE_ADDR fp
;
1099 register int regnum
;
1100 struct frame_saved_regs fsr
;
1101 struct frame_info
*fi
;
1104 fi
= get_frame_info (frame
);
1106 get_frame_saved_regs (fi
, &fsr
);
1108 #ifndef NO_PC_SPACE_QUEUE_RESTORE
1109 if (fsr
.regs
[IPSW_REGNUM
]) /* Restoring a call dummy frame */
1110 restore_pc_queue (&fsr
);
1113 for (regnum
= 31; regnum
> 0; regnum
--)
1114 if (fsr
.regs
[regnum
])
1115 write_register (regnum
, read_memory_integer (fsr
.regs
[regnum
], 4));
1117 for (regnum
= NUM_REGS
- 1; regnum
>= FP0_REGNUM
; regnum
--)
1118 if (fsr
.regs
[regnum
])
1120 read_memory (fsr
.regs
[regnum
], (char *)&freg_buffer
, 8);
1121 write_register_bytes (REGISTER_BYTE (regnum
), (char *)&freg_buffer
, 8);
1124 if (fsr
.regs
[IPSW_REGNUM
])
1125 write_register (IPSW_REGNUM
,
1126 read_memory_integer (fsr
.regs
[IPSW_REGNUM
], 4));
1128 if (fsr
.regs
[SAR_REGNUM
])
1129 write_register (SAR_REGNUM
,
1130 read_memory_integer (fsr
.regs
[SAR_REGNUM
], 4));
1132 /* If the PC was explicitly saved, then just restore it. */
1133 if (fsr
.regs
[PCOQ_TAIL_REGNUM
])
1134 write_register (PCOQ_TAIL_REGNUM
,
1135 read_memory_integer (fsr
.regs
[PCOQ_TAIL_REGNUM
], 4));
1137 /* Else use the value in %rp to set the new PC. */
1139 target_write_pc (read_register (RP_REGNUM
));
1141 write_register (FP_REGNUM
, read_memory_integer (fp
, 4));
1143 if (fsr
.regs
[IPSW_REGNUM
]) /* call dummy */
1144 write_register (SP_REGNUM
, fp
- 48);
1146 write_register (SP_REGNUM
, fp
);
1148 flush_cached_frames ();
1149 set_current_frame (create_new_frame (read_register (FP_REGNUM
),
1154 * After returning to a dummy on the stack, restore the instruction
1155 * queue space registers. */
1158 restore_pc_queue (fsr
)
1159 struct frame_saved_regs
*fsr
;
1161 CORE_ADDR pc
= read_pc ();
1162 CORE_ADDR new_pc
= read_memory_integer (fsr
->regs
[PCOQ_HEAD_REGNUM
], 4);
1164 struct target_waitstatus w
;
1167 /* Advance past break instruction in the call dummy. */
1168 write_register (PCOQ_HEAD_REGNUM
, pc
+ 4);
1169 write_register (PCOQ_TAIL_REGNUM
, pc
+ 8);
1172 * HPUX doesn't let us set the space registers or the space
1173 * registers of the PC queue through ptrace. Boo, hiss.
1174 * Conveniently, the call dummy has this sequence of instructions
1179 * So, load up the registers and single step until we are in the
1183 write_register (21, read_memory_integer (fsr
->regs
[PCSQ_HEAD_REGNUM
], 4));
1184 write_register (22, new_pc
);
1186 for (insn_count
= 0; insn_count
< 3; insn_count
++)
1188 /* FIXME: What if the inferior gets a signal right now? Want to
1189 merge this into wait_for_inferior (as a special kind of
1190 watchpoint? By setting a breakpoint at the end? Is there
1191 any other choice? Is there *any* way to do this stuff with
1192 ptrace() or some equivalent?). */
1194 target_wait (inferior_pid
, &w
);
1196 if (w
.kind
== TARGET_WAITKIND_SIGNALLED
)
1198 stop_signal
= w
.value
.sig
;
1199 terminal_ours_for_output ();
1200 printf_unfiltered ("\nProgram terminated with signal %s, %s.\n",
1201 target_signal_to_name (stop_signal
),
1202 target_signal_to_string (stop_signal
));
1203 gdb_flush (gdb_stdout
);
1207 target_terminal_ours ();
1208 (current_target
->to_fetch_registers
) (-1);
1213 hppa_push_arguments (nargs
, args
, sp
, struct_return
, struct_addr
)
1218 CORE_ADDR struct_addr
;
1220 /* array of arguments' offsets */
1221 int *offset
= (int *)alloca(nargs
* sizeof (int));
1225 for (i
= 0; i
< nargs
; i
++)
1227 /* Coerce chars to int & float to double if necessary */
1228 args
[i
] = value_arg_coerce (args
[i
]);
1230 cum
+= TYPE_LENGTH (VALUE_TYPE (args
[i
]));
1232 /* value must go at proper alignment. Assume alignment is a
1234 alignment
= hppa_alignof (VALUE_TYPE (args
[i
]));
1235 if (cum
% alignment
)
1236 cum
= (cum
+ alignment
) & -alignment
;
1239 sp
+= max ((cum
+ 7) & -8, 16);
1241 for (i
= 0; i
< nargs
; i
++)
1242 write_memory (sp
+ offset
[i
], VALUE_CONTENTS (args
[i
]),
1243 TYPE_LENGTH (VALUE_TYPE (args
[i
])));
1246 write_register (28, struct_addr
);
1251 * Insert the specified number of args and function address
1252 * into a call sequence of the above form stored at DUMMYNAME.
1254 * On the hppa we need to call the stack dummy through $$dyncall.
1255 * Therefore our version of FIX_CALL_DUMMY takes an extra argument,
1256 * real_pc, which is the location where gdb should start up the
1257 * inferior to do the function call.
1261 hppa_fix_call_dummy (dummy
, pc
, fun
, nargs
, args
, type
, gcc_p
)
1270 CORE_ADDR dyncall_addr
, sr4export_addr
;
1271 struct minimal_symbol
*msymbol
;
1272 int flags
= read_register (FLAGS_REGNUM
);
1273 struct unwind_table_entry
*u
;
1275 msymbol
= lookup_minimal_symbol ("$$dyncall", (struct objfile
*) NULL
);
1276 if (msymbol
== NULL
)
1277 error ("Can't find an address for $$dyncall trampoline");
1279 dyncall_addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
1281 /* FUN could be a procedure label, in which case we have to get
1282 its real address and the value of its GOT/DP. */
1285 /* Get the GOT/DP value for the target function. It's
1286 at *(fun+4). Note the call dummy is *NOT* allowed to
1287 trash %r19 before calling the target function. */
1288 write_register (19, read_memory_integer ((fun
& ~0x3) + 4, 4));
1290 /* Now get the real address for the function we are calling, it's
1292 fun
= (CORE_ADDR
) read_memory_integer (fun
& ~0x3, 4);
1295 /* If we are calling an import stub (eg calling into a dynamic library)
1296 then have sr4export call the magic __d_plt_call routine which is linked
1297 in from end.o. (You can't use _sr4export to call the import stub as
1298 the value in sp-24 will get fried and you end up returning to the
1299 wrong location. You can't call the import stub directly as the code
1300 to bind the PLT entry to a function can't return to a stack address.) */
1301 u
= find_unwind_entry (fun
);
1302 if (u
&& u
->stub_type
== IMPORT
)
1305 msymbol
= lookup_minimal_symbol ("__d_plt_call", (struct objfile
*) NULL
);
1306 if (msymbol
== NULL
)
1307 error ("Can't find an address for __d_plt_call trampoline");
1309 /* This is where sr4export will jump to. */
1310 new_fun
= SYMBOL_VALUE_ADDRESS (msymbol
);
1312 /* We have to store the address of the stub in __shlib_funcptr. */
1313 msymbol
= lookup_minimal_symbol ("__shlib_funcptr",
1314 (struct objfile
*)NULL
);
1315 if (msymbol
== NULL
)
1316 error ("Can't find an address for __shlib_funcptr");
1318 target_write_memory (SYMBOL_VALUE_ADDRESS (msymbol
), (char *)&fun
, 4);
1323 /* We still need sr4export's address too. */
1324 msymbol
= lookup_minimal_symbol ("_sr4export", (struct objfile
*) NULL
);
1325 if (msymbol
== NULL
)
1326 error ("Can't find an address for _sr4export trampoline");
1328 sr4export_addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
1330 store_unsigned_integer
1331 (&dummy
[9*REGISTER_SIZE
],
1333 deposit_21 (fun
>> 11,
1334 extract_unsigned_integer (&dummy
[9*REGISTER_SIZE
],
1336 store_unsigned_integer
1337 (&dummy
[10*REGISTER_SIZE
],
1339 deposit_14 (fun
& MASK_11
,
1340 extract_unsigned_integer (&dummy
[10*REGISTER_SIZE
],
1342 store_unsigned_integer
1343 (&dummy
[12*REGISTER_SIZE
],
1345 deposit_21 (sr4export_addr
>> 11,
1346 extract_unsigned_integer (&dummy
[12*REGISTER_SIZE
],
1348 store_unsigned_integer
1349 (&dummy
[13*REGISTER_SIZE
],
1351 deposit_14 (sr4export_addr
& MASK_11
,
1352 extract_unsigned_integer (&dummy
[13*REGISTER_SIZE
],
1355 write_register (22, pc
);
1357 /* If we are in a syscall, then we should call the stack dummy
1358 directly. $$dyncall is not needed as the kernel sets up the
1359 space id registers properly based on the value in %r31. In
1360 fact calling $$dyncall will not work because the value in %r22
1361 will be clobbered on the syscall exit path. */
1365 return dyncall_addr
;
1369 /* Get the PC from %r31 if currently in a syscall. Also mask out privilege
1374 int flags
= read_register (FLAGS_REGNUM
);
1377 return read_register (31) & ~0x3;
1378 return read_register (PC_REGNUM
) & ~0x3;
1381 /* Write out the PC. If currently in a syscall, then also write the new
1382 PC value into %r31. */
1387 int flags
= read_register (FLAGS_REGNUM
);
1389 /* If in a syscall, then set %r31. Also make sure to get the
1390 privilege bits set correctly. */
1392 write_register (31, (long) (v
| 0x3));
1394 write_register (PC_REGNUM
, (long) v
);
1395 write_register (NPC_REGNUM
, (long) v
+ 4);
1398 /* return the alignment of a type in bytes. Structures have the maximum
1399 alignment required by their fields. */
1405 int max_align
, align
, i
;
1406 switch (TYPE_CODE (arg
))
1411 return TYPE_LENGTH (arg
);
1412 case TYPE_CODE_ARRAY
:
1413 return hppa_alignof (TYPE_FIELD_TYPE (arg
, 0));
1414 case TYPE_CODE_STRUCT
:
1415 case TYPE_CODE_UNION
:
1417 for (i
= 0; i
< TYPE_NFIELDS (arg
); i
++)
1419 /* Bit fields have no real alignment. */
1420 if (!TYPE_FIELD_BITPOS (arg
, i
))
1422 align
= hppa_alignof (TYPE_FIELD_TYPE (arg
, i
));
1423 max_align
= max (max_align
, align
);
1432 /* Print the register regnum, or all registers if regnum is -1 */
1434 pa_do_registers_info (regnum
, fpregs
)
1438 char raw_regs
[REGISTER_BYTES
];
1441 for (i
= 0; i
< NUM_REGS
; i
++)
1442 read_relative_register_raw_bytes (i
, raw_regs
+ REGISTER_BYTE (i
));
1444 pa_print_registers (raw_regs
, regnum
, fpregs
);
1445 else if (regnum
< FP0_REGNUM
)
1446 printf_unfiltered ("%s %x\n", reg_names
[regnum
], *(long *)(raw_regs
+
1447 REGISTER_BYTE (regnum
)));
1449 pa_print_fp_reg (regnum
);
1452 pa_print_registers (raw_regs
, regnum
, fpregs
)
1459 for (i
= 0; i
< 18; i
++)
1460 printf_unfiltered ("%8.8s: %8x %8.8s: %8x %8.8s: %8x %8.8s: %8x\n",
1462 *(int *)(raw_regs
+ REGISTER_BYTE (i
)),
1464 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 18)),
1466 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 36)),
1468 *(int *)(raw_regs
+ REGISTER_BYTE (i
+ 54)));
1471 for (i
= 72; i
< NUM_REGS
; i
++)
1472 pa_print_fp_reg (i
);
1478 unsigned char raw_buffer
[MAX_REGISTER_RAW_SIZE
];
1479 unsigned char virtual_buffer
[MAX_REGISTER_VIRTUAL_SIZE
];
1481 /* Get 32bits of data. */
1482 read_relative_register_raw_bytes (i
, raw_buffer
);
1484 /* Put it in the buffer. No conversions are ever necessary. */
1485 memcpy (virtual_buffer
, raw_buffer
, REGISTER_RAW_SIZE (i
));
1487 fputs_filtered (reg_names
[i
], gdb_stdout
);
1488 print_spaces_filtered (8 - strlen (reg_names
[i
]), gdb_stdout
);
1489 fputs_filtered ("(single precision) ", gdb_stdout
);
1491 val_print (REGISTER_VIRTUAL_TYPE (i
), virtual_buffer
, 0, gdb_stdout
, 0,
1492 1, 0, Val_pretty_default
);
1493 printf_filtered ("\n");
1495 /* If "i" is even, then this register can also be a double-precision
1496 FP register. Dump it out as such. */
1499 /* Get the data in raw format for the 2nd half. */
1500 read_relative_register_raw_bytes (i
+ 1, raw_buffer
);
1502 /* Copy it into the appropriate part of the virtual buffer. */
1503 memcpy (virtual_buffer
+ REGISTER_RAW_SIZE (i
), raw_buffer
,
1504 REGISTER_RAW_SIZE (i
));
1506 /* Dump it as a double. */
1507 fputs_filtered (reg_names
[i
], gdb_stdout
);
1508 print_spaces_filtered (8 - strlen (reg_names
[i
]), gdb_stdout
);
1509 fputs_filtered ("(double precision) ", gdb_stdout
);
1511 val_print (builtin_type_double
, virtual_buffer
, 0, gdb_stdout
, 0,
1512 1, 0, Val_pretty_default
);
1513 printf_filtered ("\n");
1517 /* Figure out if PC is in a trampoline, and if so find out where
1518 the trampoline will jump to. If not in a trampoline, return zero.
1520 Simple code examination probably is not a good idea since the code
1521 sequences in trampolines can also appear in user code.
1523 We use unwinds and information from the minimal symbol table to
1524 determine when we're in a trampoline. This won't work for ELF
1525 (yet) since it doesn't create stub unwind entries. Whether or
1526 not ELF will create stub unwinds or normal unwinds for linker
1527 stubs is still being debated.
1529 This should handle simple calls through dyncall or sr4export,
1530 long calls, argument relocation stubs, and dyncall/sr4export
1531 calling an argument relocation stub. It even handles some stubs
1532 used in dynamic executables. */
1535 skip_trampoline_code (pc
, name
)
1540 long prev_inst
, curr_inst
, loc
;
1541 static CORE_ADDR dyncall
= 0;
1542 static CORE_ADDR sr4export
= 0;
1543 struct minimal_symbol
*msym
;
1544 struct unwind_table_entry
*u
;
1546 /* FIXME XXX - dyncall and sr4export must be initialized whenever we get a
1551 msym
= lookup_minimal_symbol ("$$dyncall", NULL
);
1553 dyncall
= SYMBOL_VALUE_ADDRESS (msym
);
1560 msym
= lookup_minimal_symbol ("_sr4export", NULL
);
1562 sr4export
= SYMBOL_VALUE_ADDRESS (msym
);
1567 /* Addresses passed to dyncall may *NOT* be the actual address
1568 of the funtion. So we may have to do something special. */
1571 pc
= (CORE_ADDR
) read_register (22);
1573 /* If bit 30 (counting from the left) is on, then pc is the address of
1574 the PLT entry for this function, not the address of the function
1575 itself. Bit 31 has meaning too, but only for MPE. */
1577 pc
= (CORE_ADDR
) read_memory_integer (pc
& ~0x3, 4);
1579 else if (pc
== sr4export
)
1580 pc
= (CORE_ADDR
) (read_register (22));
1582 /* Get the unwind descriptor corresponding to PC, return zero
1583 if no unwind was found. */
1584 u
= find_unwind_entry (pc
);
1588 /* If this isn't a linker stub, then return now. */
1589 if (u
->stub_type
== 0)
1590 return orig_pc
== pc
? 0 : pc
& ~0x3;
1592 /* It's a stub. Search for a branch and figure out where it goes.
1593 Note we have to handle multi insn branch sequences like ldil;ble.
1594 Most (all?) other branches can be determined by examining the contents
1595 of certain registers and the stack. */
1601 /* Make sure we haven't walked outside the range of this stub. */
1602 if (u
!= find_unwind_entry (loc
))
1604 warning ("Unable to find branch in linker stub");
1605 return orig_pc
== pc
? 0 : pc
& ~0x3;
1608 prev_inst
= curr_inst
;
1609 curr_inst
= read_memory_integer (loc
, 4);
1611 /* Does it look like a branch external using %r1? Then it's the
1612 branch from the stub to the actual function. */
1613 if ((curr_inst
& 0xffe0e000) == 0xe0202000)
1615 /* Yup. See if the previous instruction loaded
1616 a value into %r1. If so compute and return the jump address. */
1617 if ((prev_inst
& 0xffe00000) == 0x20202000)
1618 return (extract_21 (prev_inst
) + extract_17 (curr_inst
)) & ~0x3;
1621 warning ("Unable to find ldil X,%%r1 before ble Y(%%sr4,%%r1).");
1622 return orig_pc
== pc
? 0 : pc
& ~0x3;
1626 /* Does it look like bl X,rp? Another way to do a branch from the
1627 stub to the actual function. */
1628 else if ((curr_inst
& 0xffe0e000) == 0xe8400000)
1629 return (loc
+ extract_17 (curr_inst
) + 8) & ~0x3;
1631 /* Does it look like bv (rp)? Note this depends on the
1632 current stack pointer being the same as the stack
1633 pointer in the stub itself! This is a branch on from the
1634 stub back to the original caller. */
1635 else if ((curr_inst
& 0xffe0e000) == 0xe840c000)
1637 /* Yup. See if the previous instruction loaded
1639 if (prev_inst
== 0x4bc23ff1)
1640 return (read_memory_integer
1641 (read_register (SP_REGNUM
) - 8, 4)) & ~0x3;
1644 warning ("Unable to find restore of %%rp before bv (%%rp).");
1645 return orig_pc
== pc
? 0 : pc
& ~0x3;
1649 /* What about be,n 0(sr0,%rp)? It's just another way we return to
1650 the original caller from the stub. Used in dynamic executables. */
1651 else if (curr_inst
== 0xe0400002)
1653 /* The value we jump to is sitting in sp - 24. But that's
1654 loaded several instructions before the be instruction.
1655 I guess we could check for the previous instruction being
1656 mtsp %r1,%sr0 if we want to do sanity checking. */
1657 return (read_memory_integer
1658 (read_register (SP_REGNUM
) - 24, 4)) & ~0x3;
1661 /* Haven't found the branch yet, but we're still in the stub.
1667 /* For the given instruction (INST), return any adjustment it makes
1668 to the stack pointer or zero for no adjustment.
1670 This only handles instructions commonly found in prologues. */
1673 prologue_inst_adjust_sp (inst
)
1676 /* This must persist across calls. */
1677 static int save_high21
;
1679 /* The most common way to perform a stack adjustment ldo X(sp),sp */
1680 if ((inst
& 0xffffc000) == 0x37de0000)
1681 return extract_14 (inst
);
1684 if ((inst
& 0xffe00000) == 0x6fc00000)
1685 return extract_14 (inst
);
1687 /* addil high21,%r1; ldo low11,(%r1),%r30)
1688 save high bits in save_high21 for later use. */
1689 if ((inst
& 0xffe00000) == 0x28200000)
1691 save_high21
= extract_21 (inst
);
1695 if ((inst
& 0xffff0000) == 0x343e0000)
1696 return save_high21
+ extract_14 (inst
);
1698 /* fstws as used by the HP compilers. */
1699 if ((inst
& 0xffffffe0) == 0x2fd01220)
1700 return extract_5_load (inst
);
1702 /* No adjustment. */
1706 /* Return nonzero if INST is a branch of some kind, else return zero. */
1736 /* Return the register number for a GR which is saved by INST or
1737 zero it INST does not save a GR.
1739 Note we only care about full 32bit register stores (that's the only
1740 kind of stores the prologue will use). */
1743 inst_saves_gr (inst
)
1746 /* Does it look like a stw? */
1747 if ((inst
>> 26) == 0x1a)
1748 return extract_5R_store (inst
);
1750 /* Does it look like a stwm? */
1751 if ((inst
>> 26) == 0x1b)
1752 return extract_5R_store (inst
);
1757 /* Return the register number for a FR which is saved by INST or
1758 zero it INST does not save a FR.
1760 Note we only care about full 64bit register stores (that's the only
1761 kind of stores the prologue will use). */
1764 inst_saves_fr (inst
)
1767 if ((inst
& 0xfc1fffe0) == 0x2c101220)
1768 return extract_5r_store (inst
);
1772 /* Advance PC across any function entry prologue instructions
1773 to reach some "real" code.
1775 Use information in the unwind table to determine what exactly should
1776 be in the prologue. */
1783 unsigned long inst
, stack_remaining
, save_gr
, save_fr
, save_rp
, save_sp
;
1785 struct unwind_table_entry
*u
;
1787 u
= find_unwind_entry (pc
);
1791 /* If we are not at the beginning of a function, then return now. */
1792 if ((pc
& ~0x3) != u
->region_start
)
1795 /* This is how much of a frame adjustment we need to account for. */
1796 stack_remaining
= u
->Total_frame_size
<< 3;
1798 /* Magic register saves we want to know about. */
1799 save_rp
= u
->Save_RP
;
1800 save_sp
= u
->Save_SP
;
1802 /* Turn the Entry_GR field into a bitmask. */
1804 for (i
= 3; i
< u
->Entry_GR
+ 3; i
++)
1806 /* Frame pointer gets saved into a special location. */
1807 if (u
->Save_SP
&& i
== FP_REGNUM
)
1810 save_gr
|= (1 << i
);
1813 /* Turn the Entry_FR field into a bitmask too. */
1815 for (i
= 12; i
< u
->Entry_FR
+ 12; i
++)
1816 save_fr
|= (1 << i
);
1818 /* Loop until we find everything of interest or hit a branch.
1820 For unoptimized GCC code and for any HP CC code this will never ever
1821 examine any user instructions.
1823 For optimzied GCC code we're faced with problems. GCC will schedule
1824 its prologue and make prologue instructions available for delay slot
1825 filling. The end result is user code gets mixed in with the prologue
1826 and a prologue instruction may be in the delay slot of the first branch
1829 Some unexpected things are expected with debugging optimized code, so
1830 we allow this routine to walk past user instructions in optimized
1832 while (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0)
1834 status
= target_read_memory (pc
, buf
, 4);
1835 inst
= extract_unsigned_integer (buf
, 4);
1841 /* Note the interesting effects of this instruction. */
1842 stack_remaining
-= prologue_inst_adjust_sp (inst
);
1844 /* There is only one instruction used for saving RP into the stack. */
1845 if (inst
== 0x6bc23fd9)
1848 /* This is the only way we save SP into the stack. At this time
1849 the HP compilers never bother to save SP into the stack. */
1850 if ((inst
& 0xffffc000) == 0x6fc10000)
1853 /* Account for general and floating-point register saves. */
1854 save_gr
&= ~(1 << inst_saves_gr (inst
));
1855 save_fr
&= ~(1 << inst_saves_fr (inst
));
1857 /* Quit if we hit any kind of branch. This can happen if a prologue
1858 instruction is in the delay slot of the first call/branch. */
1859 if (is_branch (inst
))
1869 /* Put here the code to store, into a struct frame_saved_regs,
1870 the addresses of the saved registers of frame described by FRAME_INFO.
1871 This includes special registers such as pc and fp saved in special
1872 ways in the stack frame. sp is even more special:
1873 the address we return for it IS the sp for the next frame. */
1876 hppa_frame_find_saved_regs (frame_info
, frame_saved_regs
)
1877 struct frame_info
*frame_info
;
1878 struct frame_saved_regs
*frame_saved_regs
;
1881 struct unwind_table_entry
*u
;
1882 unsigned long inst
, stack_remaining
, save_gr
, save_fr
, save_rp
, save_sp
;
1887 /* Zero out everything. */
1888 memset (frame_saved_regs
, '\0', sizeof (struct frame_saved_regs
));
1890 /* Call dummy frames always look the same, so there's no need to
1891 examine the dummy code to determine locations of saved registers;
1892 instead, let find_dummy_frame_regs fill in the correct offsets
1893 for the saved registers. */
1894 if ((frame_info
->pc
>= frame_info
->frame
1895 && frame_info
->pc
<= (frame_info
->frame
+ CALL_DUMMY_LENGTH
1896 + 32 * 4 + (NUM_REGS
- FP0_REGNUM
) * 8
1898 find_dummy_frame_regs (frame_info
, frame_saved_regs
);
1900 /* Interrupt handlers are special too. They lay out the register
1901 state in the exact same order as the register numbers in GDB. */
1902 if (pc_in_interrupt_handler (frame_info
->pc
))
1904 for (i
= 0; i
< NUM_REGS
; i
++)
1906 /* SP is a little special. */
1908 frame_saved_regs
->regs
[SP_REGNUM
]
1909 = read_memory_integer (frame_info
->frame
+ SP_REGNUM
* 4, 4);
1911 frame_saved_regs
->regs
[i
] = frame_info
->frame
+ i
* 4;
1916 /* Handle signal handler callers. */
1917 if (frame_info
->signal_handler_caller
)
1919 FRAME_FIND_SAVED_REGS_IN_SIGTRAMP (frame_info
, frame_saved_regs
);
1923 /* Get the starting address of the function referred to by the PC
1924 saved in frame_info. */
1925 pc
= get_pc_function_start (frame_info
->pc
);
1928 u
= find_unwind_entry (pc
);
1932 /* This is how much of a frame adjustment we need to account for. */
1933 stack_remaining
= u
->Total_frame_size
<< 3;
1935 /* Magic register saves we want to know about. */
1936 save_rp
= u
->Save_RP
;
1937 save_sp
= u
->Save_SP
;
1939 /* Turn the Entry_GR field into a bitmask. */
1941 for (i
= 3; i
< u
->Entry_GR
+ 3; i
++)
1943 /* Frame pointer gets saved into a special location. */
1944 if (u
->Save_SP
&& i
== FP_REGNUM
)
1947 save_gr
|= (1 << i
);
1950 /* Turn the Entry_FR field into a bitmask too. */
1952 for (i
= 12; i
< u
->Entry_FR
+ 12; i
++)
1953 save_fr
|= (1 << i
);
1955 /* The frame always represents the value of %sp at entry to the
1956 current function (and is thus equivalent to the "saved" stack
1958 frame_saved_regs
->regs
[SP_REGNUM
] = frame_info
->frame
;
1960 /* Loop until we find everything of interest or hit a branch.
1962 For unoptimized GCC code and for any HP CC code this will never ever
1963 examine any user instructions.
1965 For optimzied GCC code we're faced with problems. GCC will schedule
1966 its prologue and make prologue instructions available for delay slot
1967 filling. The end result is user code gets mixed in with the prologue
1968 and a prologue instruction may be in the delay slot of the first branch
1971 Some unexpected things are expected with debugging optimized code, so
1972 we allow this routine to walk past user instructions in optimized
1974 while (save_gr
|| save_fr
|| save_rp
|| save_sp
|| stack_remaining
> 0)
1976 status
= target_read_memory (pc
, buf
, 4);
1977 inst
= extract_unsigned_integer (buf
, 4);
1983 /* Note the interesting effects of this instruction. */
1984 stack_remaining
-= prologue_inst_adjust_sp (inst
);
1986 /* There is only one instruction used for saving RP into the stack. */
1987 if (inst
== 0x6bc23fd9)
1990 frame_saved_regs
->regs
[RP_REGNUM
] = frame_info
->frame
- 20;
1993 /* Just note that we found the save of SP into the stack. The
1994 value for frame_saved_regs was computed above. */
1995 if ((inst
& 0xffffc000) == 0x6fc10000)
1998 /* Account for general and floating-point register saves. */
1999 reg
= inst_saves_gr (inst
);
2000 if (reg
>= 3 && reg
<= 18
2001 && (!u
->Save_SP
|| reg
!= FP_REGNUM
))
2003 save_gr
&= ~(1 << reg
);
2005 /* stwm with a positive displacement is a *post modify*. */
2006 if ((inst
>> 26) == 0x1b
2007 && extract_14 (inst
) >= 0)
2008 frame_saved_regs
->regs
[reg
] = frame_info
->frame
;
2011 /* Handle code with and without frame pointers. */
2013 frame_saved_regs
->regs
[reg
]
2014 = frame_info
->frame
+ extract_14 (inst
);
2016 frame_saved_regs
->regs
[reg
]
2017 = frame_info
->frame
+ (u
->Total_frame_size
<< 3)
2018 + extract_14 (inst
);
2023 /* GCC handles callee saved FP regs a little differently.
2025 It emits an instruction to put the value of the start of
2026 the FP store area into %r1. It then uses fstds,ma with
2027 a basereg of %r1 for the stores.
2029 HP CC emits them at the current stack pointer modifying
2030 the stack pointer as it stores each register. */
2032 /* ldo X(%r3),%r1 or ldo X(%r30),%r1. */
2033 if ((inst
& 0xffffc000) == 0x34610000
2034 || (inst
& 0xffffc000) == 0x37c10000)
2035 fp_loc
= extract_14 (inst
);
2037 reg
= inst_saves_fr (inst
);
2038 if (reg
>= 12 && reg
<= 21)
2040 /* Note +4 braindamage below is necessary because the FP status
2041 registers are internally 8 registers rather than the expected
2043 save_fr
&= ~(1 << reg
);
2046 /* 1st HP CC FP register store. After this instruction
2047 we've set enough state that the GCC and HPCC code are
2048 both handled in the same manner. */
2049 frame_saved_regs
->regs
[reg
+ FP4_REGNUM
+ 4] = frame_info
->frame
;
2054 frame_saved_regs
->regs
[reg
+ FP0_REGNUM
+ 4]
2055 = frame_info
->frame
+ fp_loc
;
2060 /* Quit if we hit any kind of branch. This can happen if a prologue
2061 instruction is in the delay slot of the first call/branch. */
2062 if (is_branch (inst
))
2070 #ifdef MAINTENANCE_CMDS
2073 unwind_command (exp
, from_tty
)
2081 struct unwind_table_entry
*u
;
2084 /* If we have an expression, evaluate it and use it as the address. */
2086 if (exp
!= 0 && *exp
!= 0)
2087 address
= parse_and_eval_address (exp
);
2091 xxx
.u
= find_unwind_entry (address
);
2095 printf_unfiltered ("Can't find unwind table entry for PC 0x%x\n", address
);
2099 printf_unfiltered ("%08x\n%08X\n%08X\n%08X\n", xxx
.foo
[0], xxx
.foo
[1], xxx
.foo
[2],
2102 #endif /* MAINTENANCE_CMDS */
2105 _initialize_hppa_tdep ()
2107 #ifdef MAINTENANCE_CMDS
2108 add_cmd ("unwind", class_maintenance
, unwind_command
,
2109 "Print unwind table entry at given address.",
2110 &maintenanceprintlist
);
2111 #endif /* MAINTENANCE_CMDS */