1586 lines
49 KiB
C
1586 lines
49 KiB
C
/* Target-dependent code for HP-UX on PA-RISC.
|
||
|
||
Copyright (C) 2002-2013 Free Software Foundation, Inc.
|
||
|
||
This file is part of GDB.
|
||
|
||
This program is free software; you can redistribute it and/or modify
|
||
it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 3 of the License, or
|
||
(at your option) any later version.
|
||
|
||
This program is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
GNU General Public License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with this program. If not, see <http://www.gnu.org/licenses/>. */
|
||
|
||
#include "defs.h"
|
||
#include "arch-utils.h"
|
||
#include "gdbcore.h"
|
||
#include "osabi.h"
|
||
#include "frame.h"
|
||
#include "frame-unwind.h"
|
||
#include "trad-frame.h"
|
||
#include "symtab.h"
|
||
#include "objfiles.h"
|
||
#include "inferior.h"
|
||
#include "infcall.h"
|
||
#include "observer.h"
|
||
#include "hppa-tdep.h"
|
||
#include "solib-som.h"
|
||
#include "solib-pa64.h"
|
||
#include "regset.h"
|
||
#include "regcache.h"
|
||
#include "exceptions.h"
|
||
|
||
#include "gdb_string.h"
|
||
|
||
#define IS_32BIT_TARGET(_gdbarch) \
|
||
((gdbarch_tdep (_gdbarch))->bytes_per_address == 4)
|
||
|
||
/* Bit in the `ss_flag' member of `struct save_state' that indicates
|
||
that the 64-bit register values are live. From
|
||
<machine/save_state.h>. */
|
||
#define HPPA_HPUX_SS_WIDEREGS 0x40
|
||
|
||
/* Offsets of various parts of `struct save_state'. From
|
||
<machine/save_state.h>. */
|
||
#define HPPA_HPUX_SS_FLAGS_OFFSET 0
|
||
#define HPPA_HPUX_SS_NARROW_OFFSET 4
|
||
#define HPPA_HPUX_SS_FPBLOCK_OFFSET 256
|
||
#define HPPA_HPUX_SS_WIDE_OFFSET 640
|
||
|
||
/* The size of `struct save_state. */
|
||
#define HPPA_HPUX_SAVE_STATE_SIZE 1152
|
||
|
||
/* The size of `struct pa89_save_state', which corresponds to PA-RISC
|
||
1.1, the lowest common denominator that we support. */
|
||
#define HPPA_HPUX_PA89_SAVE_STATE_SIZE 512
|
||
|
||
|
||
/* Forward declarations. */
|
||
extern void _initialize_hppa_hpux_tdep (void);
|
||
extern initialize_file_ftype _initialize_hppa_hpux_tdep;
|
||
|
||
static int
|
||
in_opd_section (CORE_ADDR pc)
|
||
{
|
||
struct obj_section *s;
|
||
int retval = 0;
|
||
|
||
s = find_pc_section (pc);
|
||
|
||
retval = (s != NULL
|
||
&& s->the_bfd_section->name != NULL
|
||
&& strcmp (s->the_bfd_section->name, ".opd") == 0);
|
||
return (retval);
|
||
}
|
||
|
||
/* Return one if PC is in the call path of a trampoline, else return zero.
|
||
|
||
Note we return one for *any* call trampoline (long-call, arg-reloc), not
|
||
just shared library trampolines (import, export). */
|
||
|
||
static int
|
||
hppa32_hpux_in_solib_call_trampoline (struct gdbarch *gdbarch,
|
||
CORE_ADDR pc, char *name)
|
||
{
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
struct minimal_symbol *minsym;
|
||
struct unwind_table_entry *u;
|
||
|
||
/* First see if PC is in one of the two C-library trampolines. */
|
||
if (pc == hppa_symbol_address("$$dyncall")
|
||
|| pc == hppa_symbol_address("_sr4export"))
|
||
return 1;
|
||
|
||
minsym = lookup_minimal_symbol_by_pc (pc);
|
||
if (minsym && strcmp (SYMBOL_LINKAGE_NAME (minsym), ".stub") == 0)
|
||
return 1;
|
||
|
||
/* Get the unwind descriptor corresponding to PC, return zero
|
||
if no unwind was found. */
|
||
u = find_unwind_entry (pc);
|
||
if (!u)
|
||
return 0;
|
||
|
||
/* If this isn't a linker stub, then return now. */
|
||
if (u->stub_unwind.stub_type == 0)
|
||
return 0;
|
||
|
||
/* By definition a long-branch stub is a call stub. */
|
||
if (u->stub_unwind.stub_type == LONG_BRANCH)
|
||
return 1;
|
||
|
||
/* The call and return path execute the same instructions within
|
||
an IMPORT stub! So an IMPORT stub is both a call and return
|
||
trampoline. */
|
||
if (u->stub_unwind.stub_type == IMPORT)
|
||
return 1;
|
||
|
||
/* Parameter relocation stubs always have a call path and may have a
|
||
return path. */
|
||
if (u->stub_unwind.stub_type == PARAMETER_RELOCATION
|
||
|| u->stub_unwind.stub_type == EXPORT)
|
||
{
|
||
CORE_ADDR addr;
|
||
|
||
/* Search forward from the current PC until we hit a branch
|
||
or the end of the stub. */
|
||
for (addr = pc; addr <= u->region_end; addr += 4)
|
||
{
|
||
unsigned long insn;
|
||
|
||
insn = read_memory_integer (addr, 4, byte_order);
|
||
|
||
/* Does it look like a bl? If so then it's the call path, if
|
||
we find a bv or be first, then we're on the return path. */
|
||
if ((insn & 0xfc00e000) == 0xe8000000)
|
||
return 1;
|
||
else if ((insn & 0xfc00e001) == 0xe800c000
|
||
|| (insn & 0xfc000000) == 0xe0000000)
|
||
return 0;
|
||
}
|
||
|
||
/* Should never happen. */
|
||
warning (_("Unable to find branch in parameter relocation stub."));
|
||
return 0;
|
||
}
|
||
|
||
/* Unknown stub type. For now, just return zero. */
|
||
return 0;
|
||
}
|
||
|
||
static int
|
||
hppa64_hpux_in_solib_call_trampoline (struct gdbarch *gdbarch,
|
||
CORE_ADDR pc, char *name)
|
||
{
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
|
||
/* PA64 has a completely different stub/trampoline scheme. Is it
|
||
better? Maybe. It's certainly harder to determine with any
|
||
certainty that we are in a stub because we can not refer to the
|
||
unwinders to help.
|
||
|
||
The heuristic is simple. Try to lookup the current PC value in th
|
||
minimal symbol table. If that fails, then assume we are not in a
|
||
stub and return.
|
||
|
||
Then see if the PC value falls within the section bounds for the
|
||
section containing the minimal symbol we found in the first
|
||
step. If it does, then assume we are not in a stub and return.
|
||
|
||
Finally peek at the instructions to see if they look like a stub. */
|
||
struct minimal_symbol *minsym;
|
||
asection *sec;
|
||
CORE_ADDR addr;
|
||
int insn;
|
||
|
||
minsym = lookup_minimal_symbol_by_pc (pc);
|
||
if (! minsym)
|
||
return 0;
|
||
|
||
sec = SYMBOL_OBJ_SECTION (minsym)->the_bfd_section;
|
||
|
||
if (bfd_get_section_vma (sec->owner, sec) <= pc
|
||
&& pc < (bfd_get_section_vma (sec->owner, sec)
|
||
+ bfd_section_size (sec->owner, sec)))
|
||
return 0;
|
||
|
||
/* We might be in a stub. Peek at the instructions. Stubs are 3
|
||
instructions long. */
|
||
insn = read_memory_integer (pc, 4, byte_order);
|
||
|
||
/* Find out where we think we are within the stub. */
|
||
if ((insn & 0xffffc00e) == 0x53610000)
|
||
addr = pc;
|
||
else if ((insn & 0xffffffff) == 0xe820d000)
|
||
addr = pc - 4;
|
||
else if ((insn & 0xffffc00e) == 0x537b0000)
|
||
addr = pc - 8;
|
||
else
|
||
return 0;
|
||
|
||
/* Now verify each insn in the range looks like a stub instruction. */
|
||
insn = read_memory_integer (addr, 4, byte_order);
|
||
if ((insn & 0xffffc00e) != 0x53610000)
|
||
return 0;
|
||
|
||
/* Now verify each insn in the range looks like a stub instruction. */
|
||
insn = read_memory_integer (addr + 4, 4, byte_order);
|
||
if ((insn & 0xffffffff) != 0xe820d000)
|
||
return 0;
|
||
|
||
/* Now verify each insn in the range looks like a stub instruction. */
|
||
insn = read_memory_integer (addr + 8, 4, byte_order);
|
||
if ((insn & 0xffffc00e) != 0x537b0000)
|
||
return 0;
|
||
|
||
/* Looks like a stub. */
|
||
return 1;
|
||
}
|
||
|
||
/* Return one if PC is in the return path of a trampoline, else return zero.
|
||
|
||
Note we return one for *any* call trampoline (long-call, arg-reloc), not
|
||
just shared library trampolines (import, export). */
|
||
|
||
static int
|
||
hppa_hpux_in_solib_return_trampoline (struct gdbarch *gdbarch,
|
||
CORE_ADDR pc, const char *name)
|
||
{
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
struct unwind_table_entry *u;
|
||
|
||
/* Get the unwind descriptor corresponding to PC, return zero
|
||
if no unwind was found. */
|
||
u = find_unwind_entry (pc);
|
||
if (!u)
|
||
return 0;
|
||
|
||
/* If this isn't a linker stub or it's just a long branch stub, then
|
||
return zero. */
|
||
if (u->stub_unwind.stub_type == 0 || u->stub_unwind.stub_type == LONG_BRANCH)
|
||
return 0;
|
||
|
||
/* The call and return path execute the same instructions within
|
||
an IMPORT stub! So an IMPORT stub is both a call and return
|
||
trampoline. */
|
||
if (u->stub_unwind.stub_type == IMPORT)
|
||
return 1;
|
||
|
||
/* Parameter relocation stubs always have a call path and may have a
|
||
return path. */
|
||
if (u->stub_unwind.stub_type == PARAMETER_RELOCATION
|
||
|| u->stub_unwind.stub_type == EXPORT)
|
||
{
|
||
CORE_ADDR addr;
|
||
|
||
/* Search forward from the current PC until we hit a branch
|
||
or the end of the stub. */
|
||
for (addr = pc; addr <= u->region_end; addr += 4)
|
||
{
|
||
unsigned long insn;
|
||
|
||
insn = read_memory_integer (addr, 4, byte_order);
|
||
|
||
/* Does it look like a bl? If so then it's the call path, if
|
||
we find a bv or be first, then we're on the return path. */
|
||
if ((insn & 0xfc00e000) == 0xe8000000)
|
||
return 0;
|
||
else if ((insn & 0xfc00e001) == 0xe800c000
|
||
|| (insn & 0xfc000000) == 0xe0000000)
|
||
return 1;
|
||
}
|
||
|
||
/* Should never happen. */
|
||
warning (_("Unable to find branch in parameter relocation stub."));
|
||
return 0;
|
||
}
|
||
|
||
/* Unknown stub type. For now, just return zero. */
|
||
return 0;
|
||
|
||
}
|
||
|
||
/* Figure out if PC is in a trampoline, and if so find out where
|
||
the trampoline will jump to. If not in a trampoline, return zero.
|
||
|
||
Simple code examination probably is not a good idea since the code
|
||
sequences in trampolines can also appear in user code.
|
||
|
||
We use unwinds and information from the minimal symbol table to
|
||
determine when we're in a trampoline. This won't work for ELF
|
||
(yet) since it doesn't create stub unwind entries. Whether or
|
||
not ELF will create stub unwinds or normal unwinds for linker
|
||
stubs is still being debated.
|
||
|
||
This should handle simple calls through dyncall or sr4export,
|
||
long calls, argument relocation stubs, and dyncall/sr4export
|
||
calling an argument relocation stub. It even handles some stubs
|
||
used in dynamic executables. */
|
||
|
||
static CORE_ADDR
|
||
hppa_hpux_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (frame);
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
int word_size = gdbarch_ptr_bit (gdbarch) / 8;
|
||
long orig_pc = pc;
|
||
long prev_inst, curr_inst, loc;
|
||
struct minimal_symbol *msym;
|
||
struct unwind_table_entry *u;
|
||
|
||
/* Addresses passed to dyncall may *NOT* be the actual address
|
||
of the function. So we may have to do something special. */
|
||
if (pc == hppa_symbol_address("$$dyncall"))
|
||
{
|
||
pc = (CORE_ADDR) get_frame_register_unsigned (frame, 22);
|
||
|
||
/* If bit 30 (counting from the left) is on, then pc is the address of
|
||
the PLT entry for this function, not the address of the function
|
||
itself. Bit 31 has meaning too, but only for MPE. */
|
||
if (pc & 0x2)
|
||
pc = (CORE_ADDR) read_memory_integer (pc & ~0x3, word_size,
|
||
byte_order);
|
||
}
|
||
if (pc == hppa_symbol_address("$$dyncall_external"))
|
||
{
|
||
pc = (CORE_ADDR) get_frame_register_unsigned (frame, 22);
|
||
pc = (CORE_ADDR) read_memory_integer (pc & ~0x3, word_size, byte_order);
|
||
}
|
||
else if (pc == hppa_symbol_address("_sr4export"))
|
||
pc = (CORE_ADDR) get_frame_register_unsigned (frame, 22);
|
||
|
||
/* Get the unwind descriptor corresponding to PC, return zero
|
||
if no unwind was found. */
|
||
u = find_unwind_entry (pc);
|
||
if (!u)
|
||
return 0;
|
||
|
||
/* If this isn't a linker stub, then return now. */
|
||
/* elz: attention here! (FIXME) because of a compiler/linker
|
||
error, some stubs which should have a non zero stub_unwind.stub_type
|
||
have unfortunately a value of zero. So this function would return here
|
||
as if we were not in a trampoline. To fix this, we go look at the partial
|
||
symbol information, which reports this guy as a stub.
|
||
(FIXME): Unfortunately, we are not that lucky: it turns out that the
|
||
partial symbol information is also wrong sometimes. This is because
|
||
when it is entered (somread.c::som_symtab_read()) it can happen that
|
||
if the type of the symbol (from the som) is Entry, and the symbol is
|
||
in a shared library, then it can also be a trampoline. This would be OK,
|
||
except that I believe the way they decide if we are ina shared library
|
||
does not work. SOOOO..., even if we have a regular function w/o
|
||
trampolines its minimal symbol can be assigned type mst_solib_trampoline.
|
||
Also, if we find that the symbol is a real stub, then we fix the unwind
|
||
descriptor, and define the stub type to be EXPORT.
|
||
Hopefully this is correct most of the times. */
|
||
if (u->stub_unwind.stub_type == 0)
|
||
{
|
||
|
||
/* elz: NOTE (FIXME!) once the problem with the unwind information is fixed
|
||
we can delete all the code which appears between the lines. */
|
||
/*--------------------------------------------------------------------------*/
|
||
msym = lookup_minimal_symbol_by_pc (pc);
|
||
|
||
if (msym == NULL || MSYMBOL_TYPE (msym) != mst_solib_trampoline)
|
||
return orig_pc == pc ? 0 : pc & ~0x3;
|
||
|
||
else if (msym != NULL && MSYMBOL_TYPE (msym) == mst_solib_trampoline)
|
||
{
|
||
struct objfile *objfile;
|
||
struct minimal_symbol *msymbol;
|
||
int function_found = 0;
|
||
|
||
/* Go look if there is another minimal symbol with the same name as
|
||
this one, but with type mst_text. This would happen if the msym
|
||
is an actual trampoline, in which case there would be another
|
||
symbol with the same name corresponding to the real function. */
|
||
|
||
ALL_MSYMBOLS (objfile, msymbol)
|
||
{
|
||
if (MSYMBOL_TYPE (msymbol) == mst_text
|
||
&& strcmp (SYMBOL_LINKAGE_NAME (msymbol),
|
||
SYMBOL_LINKAGE_NAME (msym)) == 0)
|
||
{
|
||
function_found = 1;
|
||
break;
|
||
}
|
||
}
|
||
|
||
if (function_found)
|
||
/* The type of msym is correct (mst_solib_trampoline), but
|
||
the unwind info is wrong, so set it to the correct value. */
|
||
u->stub_unwind.stub_type = EXPORT;
|
||
else
|
||
/* The stub type info in the unwind is correct (this is not a
|
||
trampoline), but the msym type information is wrong, it
|
||
should be mst_text. So we need to fix the msym, and also
|
||
get out of this function. */
|
||
{
|
||
MSYMBOL_TYPE (msym) = mst_text;
|
||
return orig_pc == pc ? 0 : pc & ~0x3;
|
||
}
|
||
}
|
||
|
||
/*--------------------------------------------------------------------------*/
|
||
}
|
||
|
||
/* It's a stub. Search for a branch and figure out where it goes.
|
||
Note we have to handle multi insn branch sequences like ldil;ble.
|
||
Most (all?) other branches can be determined by examining the contents
|
||
of certain registers and the stack. */
|
||
|
||
loc = pc;
|
||
curr_inst = 0;
|
||
prev_inst = 0;
|
||
while (1)
|
||
{
|
||
/* Make sure we haven't walked outside the range of this stub. */
|
||
if (u != find_unwind_entry (loc))
|
||
{
|
||
warning (_("Unable to find branch in linker stub"));
|
||
return orig_pc == pc ? 0 : pc & ~0x3;
|
||
}
|
||
|
||
prev_inst = curr_inst;
|
||
curr_inst = read_memory_integer (loc, 4, byte_order);
|
||
|
||
/* Does it look like a branch external using %r1? Then it's the
|
||
branch from the stub to the actual function. */
|
||
if ((curr_inst & 0xffe0e000) == 0xe0202000)
|
||
{
|
||
/* Yup. See if the previous instruction loaded
|
||
a value into %r1. If so compute and return the jump address. */
|
||
if ((prev_inst & 0xffe00000) == 0x20200000)
|
||
return (hppa_extract_21 (prev_inst)
|
||
+ hppa_extract_17 (curr_inst)) & ~0x3;
|
||
else
|
||
{
|
||
warning (_("Unable to find ldil X,%%r1 "
|
||
"before ble Y(%%sr4,%%r1)."));
|
||
return orig_pc == pc ? 0 : pc & ~0x3;
|
||
}
|
||
}
|
||
|
||
/* Does it look like a be 0(sr0,%r21)? OR
|
||
Does it look like a be, n 0(sr0,%r21)? OR
|
||
Does it look like a bve (r21)? (this is on PA2.0)
|
||
Does it look like a bve, n(r21)? (this is also on PA2.0)
|
||
That's the branch from an
|
||
import stub to an export stub.
|
||
|
||
It is impossible to determine the target of the branch via
|
||
simple examination of instructions and/or data (consider
|
||
that the address in the plabel may be the address of the
|
||
bind-on-reference routine in the dynamic loader).
|
||
|
||
So we have try an alternative approach.
|
||
|
||
Get the name of the symbol at our current location; it should
|
||
be a stub symbol with the same name as the symbol in the
|
||
shared library.
|
||
|
||
Then lookup a minimal symbol with the same name; we should
|
||
get the minimal symbol for the target routine in the shared
|
||
library as those take precedence of import/export stubs. */
|
||
if ((curr_inst == 0xe2a00000) ||
|
||
(curr_inst == 0xe2a00002) ||
|
||
(curr_inst == 0xeaa0d000) ||
|
||
(curr_inst == 0xeaa0d002))
|
||
{
|
||
struct minimal_symbol *stubsym, *libsym;
|
||
|
||
stubsym = lookup_minimal_symbol_by_pc (loc);
|
||
if (stubsym == NULL)
|
||
{
|
||
warning (_("Unable to find symbol for 0x%lx"), loc);
|
||
return orig_pc == pc ? 0 : pc & ~0x3;
|
||
}
|
||
|
||
libsym = lookup_minimal_symbol (SYMBOL_LINKAGE_NAME (stubsym),
|
||
NULL, NULL);
|
||
if (libsym == NULL)
|
||
{
|
||
warning (_("Unable to find library symbol for %s."),
|
||
SYMBOL_PRINT_NAME (stubsym));
|
||
return orig_pc == pc ? 0 : pc & ~0x3;
|
||
}
|
||
|
||
return SYMBOL_VALUE (libsym);
|
||
}
|
||
|
||
/* Does it look like bl X,%rp or bl X,%r0? Another way to do a
|
||
branch from the stub to the actual function. */
|
||
/*elz */
|
||
else if ((curr_inst & 0xffe0e000) == 0xe8400000
|
||
|| (curr_inst & 0xffe0e000) == 0xe8000000
|
||
|| (curr_inst & 0xffe0e000) == 0xe800A000)
|
||
return (loc + hppa_extract_17 (curr_inst) + 8) & ~0x3;
|
||
|
||
/* Does it look like bv (rp)? Note this depends on the
|
||
current stack pointer being the same as the stack
|
||
pointer in the stub itself! This is a branch on from the
|
||
stub back to the original caller. */
|
||
/*else if ((curr_inst & 0xffe0e000) == 0xe840c000) */
|
||
else if ((curr_inst & 0xffe0f000) == 0xe840c000)
|
||
{
|
||
/* Yup. See if the previous instruction loaded
|
||
rp from sp - 8. */
|
||
if (prev_inst == 0x4bc23ff1)
|
||
{
|
||
CORE_ADDR sp;
|
||
sp = get_frame_register_unsigned (frame, HPPA_SP_REGNUM);
|
||
return read_memory_integer (sp - 8, 4, byte_order) & ~0x3;
|
||
}
|
||
else
|
||
{
|
||
warning (_("Unable to find restore of %%rp before bv (%%rp)."));
|
||
return orig_pc == pc ? 0 : pc & ~0x3;
|
||
}
|
||
}
|
||
|
||
/* elz: added this case to capture the new instruction
|
||
at the end of the return part of an export stub used by
|
||
the PA2.0: BVE, n (rp) */
|
||
else if ((curr_inst & 0xffe0f000) == 0xe840d000)
|
||
{
|
||
return (read_memory_integer
|
||
(get_frame_register_unsigned (frame, HPPA_SP_REGNUM) - 24,
|
||
word_size, byte_order)) & ~0x3;
|
||
}
|
||
|
||
/* What about be,n 0(sr0,%rp)? It's just another way we return to
|
||
the original caller from the stub. Used in dynamic executables. */
|
||
else if (curr_inst == 0xe0400002)
|
||
{
|
||
/* The value we jump to is sitting in sp - 24. But that's
|
||
loaded several instructions before the be instruction.
|
||
I guess we could check for the previous instruction being
|
||
mtsp %r1,%sr0 if we want to do sanity checking. */
|
||
return (read_memory_integer
|
||
(get_frame_register_unsigned (frame, HPPA_SP_REGNUM) - 24,
|
||
word_size, byte_order)) & ~0x3;
|
||
}
|
||
|
||
/* Haven't found the branch yet, but we're still in the stub.
|
||
Keep looking. */
|
||
loc += 4;
|
||
}
|
||
}
|
||
|
||
static void
|
||
hppa_skip_permanent_breakpoint (struct regcache *regcache)
|
||
{
|
||
/* To step over a breakpoint instruction on the PA takes some
|
||
fiddling with the instruction address queue.
|
||
|
||
When we stop at a breakpoint, the IA queue front (the instruction
|
||
we're executing now) points at the breakpoint instruction, and
|
||
the IA queue back (the next instruction to execute) points to
|
||
whatever instruction we would execute after the breakpoint, if it
|
||
were an ordinary instruction. This is the case even if the
|
||
breakpoint is in the delay slot of a branch instruction.
|
||
|
||
Clearly, to step past the breakpoint, we need to set the queue
|
||
front to the back. But what do we put in the back? What
|
||
instruction comes after that one? Because of the branch delay
|
||
slot, the next insn is always at the back + 4. */
|
||
|
||
ULONGEST pcoq_tail, pcsq_tail;
|
||
regcache_cooked_read_unsigned (regcache, HPPA_PCOQ_TAIL_REGNUM, &pcoq_tail);
|
||
regcache_cooked_read_unsigned (regcache, HPPA_PCSQ_TAIL_REGNUM, &pcsq_tail);
|
||
|
||
regcache_cooked_write_unsigned (regcache, HPPA_PCOQ_HEAD_REGNUM, pcoq_tail);
|
||
regcache_cooked_write_unsigned (regcache, HPPA_PCSQ_HEAD_REGNUM, pcsq_tail);
|
||
|
||
regcache_cooked_write_unsigned (regcache,
|
||
HPPA_PCOQ_TAIL_REGNUM, pcoq_tail + 4);
|
||
/* We can leave the tail's space the same, since there's no jump. */
|
||
}
|
||
|
||
|
||
/* Signal frames. */
|
||
struct hppa_hpux_sigtramp_unwind_cache
|
||
{
|
||
CORE_ADDR base;
|
||
struct trad_frame_saved_reg *saved_regs;
|
||
};
|
||
|
||
static int hppa_hpux_tramp_reg[] = {
|
||
HPPA_SAR_REGNUM,
|
||
HPPA_PCOQ_HEAD_REGNUM,
|
||
HPPA_PCSQ_HEAD_REGNUM,
|
||
HPPA_PCOQ_TAIL_REGNUM,
|
||
HPPA_PCSQ_TAIL_REGNUM,
|
||
HPPA_EIEM_REGNUM,
|
||
HPPA_IIR_REGNUM,
|
||
HPPA_ISR_REGNUM,
|
||
HPPA_IOR_REGNUM,
|
||
HPPA_IPSW_REGNUM,
|
||
-1,
|
||
HPPA_SR4_REGNUM,
|
||
HPPA_SR4_REGNUM + 1,
|
||
HPPA_SR4_REGNUM + 2,
|
||
HPPA_SR4_REGNUM + 3,
|
||
HPPA_SR4_REGNUM + 4,
|
||
HPPA_SR4_REGNUM + 5,
|
||
HPPA_SR4_REGNUM + 6,
|
||
HPPA_SR4_REGNUM + 7,
|
||
HPPA_RCR_REGNUM,
|
||
HPPA_PID0_REGNUM,
|
||
HPPA_PID1_REGNUM,
|
||
HPPA_CCR_REGNUM,
|
||
HPPA_PID2_REGNUM,
|
||
HPPA_PID3_REGNUM,
|
||
HPPA_TR0_REGNUM,
|
||
HPPA_TR0_REGNUM + 1,
|
||
HPPA_TR0_REGNUM + 2,
|
||
HPPA_CR27_REGNUM
|
||
};
|
||
|
||
static struct hppa_hpux_sigtramp_unwind_cache *
|
||
hppa_hpux_sigtramp_frame_unwind_cache (struct frame_info *this_frame,
|
||
void **this_cache)
|
||
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
struct hppa_hpux_sigtramp_unwind_cache *info;
|
||
unsigned int flag;
|
||
CORE_ADDR sp, scptr, off;
|
||
int i, incr, szoff;
|
||
|
||
if (*this_cache)
|
||
return *this_cache;
|
||
|
||
info = FRAME_OBSTACK_ZALLOC (struct hppa_hpux_sigtramp_unwind_cache);
|
||
*this_cache = info;
|
||
info->saved_regs = trad_frame_alloc_saved_regs (this_frame);
|
||
|
||
sp = get_frame_register_unsigned (this_frame, HPPA_SP_REGNUM);
|
||
|
||
if (IS_32BIT_TARGET (gdbarch))
|
||
scptr = sp - 1352;
|
||
else
|
||
scptr = sp - 1520;
|
||
|
||
off = scptr;
|
||
|
||
/* See /usr/include/machine/save_state.h for the structure of the
|
||
save_state_t structure. */
|
||
|
||
flag = read_memory_unsigned_integer (scptr + HPPA_HPUX_SS_FLAGS_OFFSET,
|
||
4, byte_order);
|
||
|
||
if (!(flag & HPPA_HPUX_SS_WIDEREGS))
|
||
{
|
||
/* Narrow registers. */
|
||
off = scptr + HPPA_HPUX_SS_NARROW_OFFSET;
|
||
incr = 4;
|
||
szoff = 0;
|
||
}
|
||
else
|
||
{
|
||
/* Wide registers. */
|
||
off = scptr + HPPA_HPUX_SS_WIDE_OFFSET + 8;
|
||
incr = 8;
|
||
szoff = (tdep->bytes_per_address == 4 ? 4 : 0);
|
||
}
|
||
|
||
for (i = 1; i < 32; i++)
|
||
{
|
||
info->saved_regs[HPPA_R0_REGNUM + i].addr = off + szoff;
|
||
off += incr;
|
||
}
|
||
|
||
for (i = 0; i < ARRAY_SIZE (hppa_hpux_tramp_reg); i++)
|
||
{
|
||
if (hppa_hpux_tramp_reg[i] > 0)
|
||
info->saved_regs[hppa_hpux_tramp_reg[i]].addr = off + szoff;
|
||
|
||
off += incr;
|
||
}
|
||
|
||
/* TODO: fp regs */
|
||
|
||
info->base = get_frame_register_unsigned (this_frame, HPPA_SP_REGNUM);
|
||
|
||
return info;
|
||
}
|
||
|
||
static void
|
||
hppa_hpux_sigtramp_frame_this_id (struct frame_info *this_frame,
|
||
void **this_prologue_cache,
|
||
struct frame_id *this_id)
|
||
{
|
||
struct hppa_hpux_sigtramp_unwind_cache *info
|
||
= hppa_hpux_sigtramp_frame_unwind_cache (this_frame, this_prologue_cache);
|
||
|
||
*this_id = frame_id_build (info->base, get_frame_pc (this_frame));
|
||
}
|
||
|
||
static struct value *
|
||
hppa_hpux_sigtramp_frame_prev_register (struct frame_info *this_frame,
|
||
void **this_prologue_cache,
|
||
int regnum)
|
||
{
|
||
struct hppa_hpux_sigtramp_unwind_cache *info
|
||
= hppa_hpux_sigtramp_frame_unwind_cache (this_frame, this_prologue_cache);
|
||
|
||
return hppa_frame_prev_register_helper (this_frame,
|
||
info->saved_regs, regnum);
|
||
}
|
||
|
||
static int
|
||
hppa_hpux_sigtramp_unwind_sniffer (const struct frame_unwind *self,
|
||
struct frame_info *this_frame,
|
||
void **this_cache)
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
struct unwind_table_entry *u;
|
||
CORE_ADDR pc = get_frame_pc (this_frame);
|
||
|
||
u = find_unwind_entry (pc);
|
||
|
||
/* If this is an export stub, try to get the unwind descriptor for
|
||
the actual function itself. */
|
||
if (u && u->stub_unwind.stub_type == EXPORT)
|
||
{
|
||
gdb_byte buf[HPPA_INSN_SIZE];
|
||
unsigned long insn;
|
||
|
||
if (!safe_frame_unwind_memory (this_frame, u->region_start,
|
||
buf, sizeof buf))
|
||
return 0;
|
||
|
||
insn = extract_unsigned_integer (buf, sizeof buf, byte_order);
|
||
if ((insn & 0xffe0e000) == 0xe8400000)
|
||
u = find_unwind_entry(u->region_start + hppa_extract_17 (insn) + 8);
|
||
}
|
||
|
||
if (u && u->HP_UX_interrupt_marker)
|
||
return 1;
|
||
|
||
return 0;
|
||
}
|
||
|
||
static const struct frame_unwind hppa_hpux_sigtramp_frame_unwind = {
|
||
SIGTRAMP_FRAME,
|
||
default_frame_unwind_stop_reason,
|
||
hppa_hpux_sigtramp_frame_this_id,
|
||
hppa_hpux_sigtramp_frame_prev_register,
|
||
NULL,
|
||
hppa_hpux_sigtramp_unwind_sniffer
|
||
};
|
||
|
||
static CORE_ADDR
|
||
hppa32_hpux_find_global_pointer (struct gdbarch *gdbarch,
|
||
struct value *function)
|
||
{
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
CORE_ADDR faddr;
|
||
|
||
faddr = value_as_address (function);
|
||
|
||
/* Is this a plabel? If so, dereference it to get the gp value. */
|
||
if (faddr & 2)
|
||
{
|
||
int status;
|
||
gdb_byte buf[4];
|
||
|
||
faddr &= ~3;
|
||
|
||
status = target_read_memory (faddr + 4, buf, sizeof (buf));
|
||
if (status == 0)
|
||
return extract_unsigned_integer (buf, sizeof (buf), byte_order);
|
||
}
|
||
|
||
return gdbarch_tdep (gdbarch)->solib_get_got_by_pc (faddr);
|
||
}
|
||
|
||
static CORE_ADDR
|
||
hppa64_hpux_find_global_pointer (struct gdbarch *gdbarch,
|
||
struct value *function)
|
||
{
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
CORE_ADDR faddr;
|
||
gdb_byte buf[32];
|
||
|
||
faddr = value_as_address (function);
|
||
|
||
if (in_opd_section (faddr))
|
||
{
|
||
target_read_memory (faddr, buf, sizeof (buf));
|
||
return extract_unsigned_integer (&buf[24], 8, byte_order);
|
||
}
|
||
else
|
||
{
|
||
return gdbarch_tdep (gdbarch)->solib_get_got_by_pc (faddr);
|
||
}
|
||
}
|
||
|
||
static unsigned int ldsid_pattern[] = {
|
||
0x000010a0, /* ldsid (rX),rY */
|
||
0x00001820, /* mtsp rY,sr0 */
|
||
0xe0000000 /* be,n (sr0,rX) */
|
||
};
|
||
|
||
static CORE_ADDR
|
||
hppa_hpux_search_pattern (struct gdbarch *gdbarch,
|
||
CORE_ADDR start, CORE_ADDR end,
|
||
unsigned int *patterns, int count)
|
||
{
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
int num_insns = (end - start + HPPA_INSN_SIZE) / HPPA_INSN_SIZE;
|
||
unsigned int *insns;
|
||
gdb_byte *buf;
|
||
int offset, i;
|
||
|
||
buf = alloca (num_insns * HPPA_INSN_SIZE);
|
||
insns = alloca (num_insns * sizeof (unsigned int));
|
||
|
||
read_memory (start, buf, num_insns * HPPA_INSN_SIZE);
|
||
for (i = 0; i < num_insns; i++, buf += HPPA_INSN_SIZE)
|
||
insns[i] = extract_unsigned_integer (buf, HPPA_INSN_SIZE, byte_order);
|
||
|
||
for (offset = 0; offset <= num_insns - count; offset++)
|
||
{
|
||
for (i = 0; i < count; i++)
|
||
{
|
||
if ((insns[offset + i] & patterns[i]) != patterns[i])
|
||
break;
|
||
}
|
||
if (i == count)
|
||
break;
|
||
}
|
||
|
||
if (offset <= num_insns - count)
|
||
return start + offset * HPPA_INSN_SIZE;
|
||
else
|
||
return 0;
|
||
}
|
||
|
||
static CORE_ADDR
|
||
hppa32_hpux_search_dummy_call_sequence (struct gdbarch *gdbarch, CORE_ADDR pc,
|
||
int *argreg)
|
||
{
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
struct objfile *obj;
|
||
struct obj_section *sec;
|
||
struct hppa_objfile_private *priv;
|
||
struct frame_info *frame;
|
||
struct unwind_table_entry *u;
|
||
CORE_ADDR addr, rp;
|
||
gdb_byte buf[4];
|
||
unsigned int insn;
|
||
|
||
sec = find_pc_section (pc);
|
||
obj = sec->objfile;
|
||
priv = objfile_data (obj, hppa_objfile_priv_data);
|
||
|
||
if (!priv)
|
||
priv = hppa_init_objfile_priv_data (obj);
|
||
if (!priv)
|
||
error (_("Internal error creating objfile private data."));
|
||
|
||
/* Use the cached value if we have one. */
|
||
if (priv->dummy_call_sequence_addr != 0)
|
||
{
|
||
*argreg = priv->dummy_call_sequence_reg;
|
||
return priv->dummy_call_sequence_addr;
|
||
}
|
||
|
||
/* First try a heuristic; if we are in a shared library call, our return
|
||
pointer is likely to point at an export stub. */
|
||
frame = get_current_frame ();
|
||
rp = frame_unwind_register_unsigned (frame, 2);
|
||
u = find_unwind_entry (rp);
|
||
if (u && u->stub_unwind.stub_type == EXPORT)
|
||
{
|
||
addr = hppa_hpux_search_pattern (gdbarch,
|
||
u->region_start, u->region_end,
|
||
ldsid_pattern,
|
||
ARRAY_SIZE (ldsid_pattern));
|
||
if (addr)
|
||
goto found_pattern;
|
||
}
|
||
|
||
/* Next thing to try is to look for an export stub. */
|
||
if (priv->unwind_info)
|
||
{
|
||
int i;
|
||
|
||
for (i = 0; i < priv->unwind_info->last; i++)
|
||
{
|
||
struct unwind_table_entry *u;
|
||
u = &priv->unwind_info->table[i];
|
||
if (u->stub_unwind.stub_type == EXPORT)
|
||
{
|
||
addr = hppa_hpux_search_pattern (gdbarch,
|
||
u->region_start, u->region_end,
|
||
ldsid_pattern,
|
||
ARRAY_SIZE (ldsid_pattern));
|
||
if (addr)
|
||
{
|
||
goto found_pattern;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Finally, if this is the main executable, try to locate a sequence
|
||
from noshlibs */
|
||
addr = hppa_symbol_address ("noshlibs");
|
||
sec = find_pc_section (addr);
|
||
|
||
if (sec && sec->objfile == obj)
|
||
{
|
||
CORE_ADDR start, end;
|
||
|
||
find_pc_partial_function (addr, NULL, &start, &end);
|
||
if (start != 0 && end != 0)
|
||
{
|
||
addr = hppa_hpux_search_pattern (gdbarch, start, end, ldsid_pattern,
|
||
ARRAY_SIZE (ldsid_pattern));
|
||
if (addr)
|
||
goto found_pattern;
|
||
}
|
||
}
|
||
|
||
/* Can't find a suitable sequence. */
|
||
return 0;
|
||
|
||
found_pattern:
|
||
target_read_memory (addr, buf, sizeof (buf));
|
||
insn = extract_unsigned_integer (buf, sizeof (buf), byte_order);
|
||
priv->dummy_call_sequence_addr = addr;
|
||
priv->dummy_call_sequence_reg = (insn >> 21) & 0x1f;
|
||
|
||
*argreg = priv->dummy_call_sequence_reg;
|
||
return priv->dummy_call_sequence_addr;
|
||
}
|
||
|
||
static CORE_ADDR
|
||
hppa64_hpux_search_dummy_call_sequence (struct gdbarch *gdbarch, CORE_ADDR pc,
|
||
int *argreg)
|
||
{
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
struct objfile *obj;
|
||
struct obj_section *sec;
|
||
struct hppa_objfile_private *priv;
|
||
CORE_ADDR addr;
|
||
struct minimal_symbol *msym;
|
||
|
||
sec = find_pc_section (pc);
|
||
obj = sec->objfile;
|
||
priv = objfile_data (obj, hppa_objfile_priv_data);
|
||
|
||
if (!priv)
|
||
priv = hppa_init_objfile_priv_data (obj);
|
||
if (!priv)
|
||
error (_("Internal error creating objfile private data."));
|
||
|
||
/* Use the cached value if we have one. */
|
||
if (priv->dummy_call_sequence_addr != 0)
|
||
{
|
||
*argreg = priv->dummy_call_sequence_reg;
|
||
return priv->dummy_call_sequence_addr;
|
||
}
|
||
|
||
/* FIXME: Without stub unwind information, locating a suitable sequence is
|
||
fairly difficult. For now, we implement a very naive and inefficient
|
||
scheme; try to read in blocks of code, and look for a "bve,n (rp)"
|
||
instruction. These are likely to occur at the end of functions, so
|
||
we only look at the last two instructions of each function. */
|
||
ALL_OBJFILE_MSYMBOLS (obj, msym)
|
||
{
|
||
CORE_ADDR begin, end;
|
||
const char *name;
|
||
gdb_byte buf[2 * HPPA_INSN_SIZE];
|
||
int offset;
|
||
|
||
find_pc_partial_function (SYMBOL_VALUE_ADDRESS (msym), &name,
|
||
&begin, &end);
|
||
|
||
if (name == NULL || begin == 0 || end == 0)
|
||
continue;
|
||
|
||
if (target_read_memory (end - sizeof (buf), buf, sizeof (buf)) == 0)
|
||
{
|
||
for (offset = 0; offset < sizeof (buf); offset++)
|
||
{
|
||
unsigned int insn;
|
||
|
||
insn = extract_unsigned_integer (buf + offset,
|
||
HPPA_INSN_SIZE, byte_order);
|
||
if (insn == 0xe840d002) /* bve,n (rp) */
|
||
{
|
||
addr = (end - sizeof (buf)) + offset;
|
||
goto found_pattern;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Can't find a suitable sequence. */
|
||
return 0;
|
||
|
||
found_pattern:
|
||
priv->dummy_call_sequence_addr = addr;
|
||
/* Right now we only look for a "bve,l (rp)" sequence, so the register is
|
||
always HPPA_RP_REGNUM. */
|
||
priv->dummy_call_sequence_reg = HPPA_RP_REGNUM;
|
||
|
||
*argreg = priv->dummy_call_sequence_reg;
|
||
return priv->dummy_call_sequence_addr;
|
||
}
|
||
|
||
static CORE_ADDR
|
||
hppa_hpux_find_import_stub_for_addr (CORE_ADDR funcaddr)
|
||
{
|
||
struct objfile *objfile;
|
||
struct minimal_symbol *funsym, *stubsym;
|
||
CORE_ADDR stubaddr;
|
||
|
||
funsym = lookup_minimal_symbol_by_pc (funcaddr);
|
||
stubaddr = 0;
|
||
|
||
ALL_OBJFILES (objfile)
|
||
{
|
||
stubsym = lookup_minimal_symbol_solib_trampoline
|
||
(SYMBOL_LINKAGE_NAME (funsym), objfile);
|
||
|
||
if (stubsym)
|
||
{
|
||
struct unwind_table_entry *u;
|
||
|
||
u = find_unwind_entry (SYMBOL_VALUE (stubsym));
|
||
if (u == NULL
|
||
|| (u->stub_unwind.stub_type != IMPORT
|
||
&& u->stub_unwind.stub_type != IMPORT_SHLIB))
|
||
continue;
|
||
|
||
stubaddr = SYMBOL_VALUE (stubsym);
|
||
|
||
/* If we found an IMPORT stub, then we can stop searching;
|
||
if we found an IMPORT_SHLIB, we want to continue the search
|
||
in the hopes that we will find an IMPORT stub. */
|
||
if (u->stub_unwind.stub_type == IMPORT)
|
||
break;
|
||
}
|
||
}
|
||
|
||
return stubaddr;
|
||
}
|
||
|
||
static int
|
||
hppa_hpux_sr_for_addr (struct gdbarch *gdbarch, CORE_ADDR addr)
|
||
{
|
||
int sr;
|
||
/* The space register to use is encoded in the top 2 bits of the address. */
|
||
sr = addr >> (gdbarch_tdep (gdbarch)->bytes_per_address * 8 - 2);
|
||
return sr + 4;
|
||
}
|
||
|
||
static CORE_ADDR
|
||
hppa_hpux_find_dummy_bpaddr (CORE_ADDR addr)
|
||
{
|
||
/* In order for us to restore the space register to its starting state,
|
||
we need the dummy trampoline to return to an instruction address in
|
||
the same space as where we started the call. We used to place the
|
||
breakpoint near the current pc, however, this breaks nested dummy calls
|
||
as the nested call will hit the breakpoint address and terminate
|
||
prematurely. Instead, we try to look for an address in the same space to
|
||
put the breakpoint.
|
||
|
||
This is similar in spirit to putting the breakpoint at the "entry point"
|
||
of an executable. */
|
||
|
||
struct obj_section *sec;
|
||
struct unwind_table_entry *u;
|
||
struct minimal_symbol *msym;
|
||
CORE_ADDR func;
|
||
|
||
sec = find_pc_section (addr);
|
||
if (sec)
|
||
{
|
||
/* First try the lowest address in the section; we can use it as long
|
||
as it is "regular" code (i.e. not a stub). */
|
||
u = find_unwind_entry (obj_section_addr (sec));
|
||
if (!u || u->stub_unwind.stub_type == 0)
|
||
return obj_section_addr (sec);
|
||
|
||
/* Otherwise, we need to find a symbol for a regular function. We
|
||
do this by walking the list of msymbols in the objfile. The symbol
|
||
we find should not be the same as the function that was passed in. */
|
||
|
||
/* FIXME: this is broken, because we can find a function that will be
|
||
called by the dummy call target function, which will still not
|
||
work. */
|
||
|
||
find_pc_partial_function (addr, NULL, &func, NULL);
|
||
ALL_OBJFILE_MSYMBOLS (sec->objfile, msym)
|
||
{
|
||
u = find_unwind_entry (SYMBOL_VALUE_ADDRESS (msym));
|
||
if (func != SYMBOL_VALUE_ADDRESS (msym)
|
||
&& (!u || u->stub_unwind.stub_type == 0))
|
||
return SYMBOL_VALUE_ADDRESS (msym);
|
||
}
|
||
}
|
||
|
||
warning (_("Cannot find suitable address to place dummy breakpoint; nested "
|
||
"calls may fail."));
|
||
return addr - 4;
|
||
}
|
||
|
||
static CORE_ADDR
|
||
hppa_hpux_push_dummy_code (struct gdbarch *gdbarch, CORE_ADDR sp,
|
||
CORE_ADDR funcaddr,
|
||
struct value **args, int nargs,
|
||
struct type *value_type,
|
||
CORE_ADDR *real_pc, CORE_ADDR *bp_addr,
|
||
struct regcache *regcache)
|
||
{
|
||
CORE_ADDR pc, stubaddr;
|
||
int argreg = 0;
|
||
|
||
pc = regcache_read_pc (regcache);
|
||
|
||
/* Note: we don't want to pass a function descriptor here; push_dummy_call
|
||
fills in the PIC register for us. */
|
||
funcaddr = gdbarch_convert_from_func_ptr_addr (gdbarch, funcaddr, NULL);
|
||
|
||
/* The simple case is where we call a function in the same space that we are
|
||
currently in; in that case we don't really need to do anything. */
|
||
if (hppa_hpux_sr_for_addr (gdbarch, pc)
|
||
== hppa_hpux_sr_for_addr (gdbarch, funcaddr))
|
||
{
|
||
/* Intraspace call. */
|
||
*bp_addr = hppa_hpux_find_dummy_bpaddr (pc);
|
||
*real_pc = funcaddr;
|
||
regcache_cooked_write_unsigned (regcache, HPPA_RP_REGNUM, *bp_addr);
|
||
|
||
return sp;
|
||
}
|
||
|
||
/* In order to make an interspace call, we need to go through a stub.
|
||
gcc supplies an appropriate stub called "__gcc_plt_call", however, if
|
||
an application is compiled with HP compilers then this stub is not
|
||
available. We used to fallback to "__d_plt_call", however that stub
|
||
is not entirely useful for us because it doesn't do an interspace
|
||
return back to the caller. Also, on hppa64-hpux, there is no
|
||
__gcc_plt_call available. In order to keep the code uniform, we
|
||
instead don't use either of these stubs, but instead write our own
|
||
onto the stack.
|
||
|
||
A problem arises since the stack is located in a different space than
|
||
code, so in order to branch to a stack stub, we will need to do an
|
||
interspace branch. Previous versions of gdb did this by modifying code
|
||
at the current pc and doing single-stepping to set the pcsq. Since this
|
||
is highly undesirable, we use a different scheme:
|
||
|
||
All we really need to do the branch to the stub is a short instruction
|
||
sequence like this:
|
||
|
||
PA1.1:
|
||
ldsid (rX),r1
|
||
mtsp r1,sr0
|
||
be,n (sr0,rX)
|
||
|
||
PA2.0:
|
||
bve,n (sr0,rX)
|
||
|
||
Instead of writing these sequences ourselves, we can find it in
|
||
the instruction stream that belongs to the current space. While this
|
||
seems difficult at first, we are actually guaranteed to find the sequences
|
||
in several places:
|
||
|
||
For 32-bit code:
|
||
- in export stubs for shared libraries
|
||
- in the "noshlibs" routine in the main module
|
||
|
||
For 64-bit code:
|
||
- at the end of each "regular" function
|
||
|
||
We cache the address of these sequences in the objfile's private data
|
||
since these operations can potentially be quite expensive.
|
||
|
||
So, what we do is:
|
||
- write a stack trampoline
|
||
- look for a suitable instruction sequence in the current space
|
||
- point the sequence at the trampoline
|
||
- set the return address of the trampoline to the current space
|
||
(see hppa_hpux_find_dummy_call_bpaddr)
|
||
- set the continuing address of the "dummy code" as the sequence. */
|
||
|
||
if (IS_32BIT_TARGET (gdbarch))
|
||
{
|
||
#define INSN(I1, I2, I3, I4) 0x ## I1, 0x ## I2, 0x ## I3, 0x ## I4
|
||
static const gdb_byte hppa32_tramp[] = {
|
||
INSN(0f,df,12,91), /* stw r31,-8(,sp) */
|
||
INSN(02,c0,10,a1), /* ldsid (,r22),r1 */
|
||
INSN(00,01,18,20), /* mtsp r1,sr0 */
|
||
INSN(e6,c0,00,00), /* be,l 0(sr0,r22),%sr0,%r31 */
|
||
INSN(08,1f,02,42), /* copy r31,rp */
|
||
INSN(0f,d1,10,82), /* ldw -8(,sp),rp */
|
||
INSN(00,40,10,a1), /* ldsid (,rp),r1 */
|
||
INSN(00,01,18,20), /* mtsp r1,sr0 */
|
||
INSN(e0,40,00,00), /* be 0(sr0,rp) */
|
||
INSN(08,00,02,40) /* nop */
|
||
};
|
||
|
||
/* for hppa32, we must call the function through a stub so that on
|
||
return it can return to the space of our trampoline. */
|
||
stubaddr = hppa_hpux_find_import_stub_for_addr (funcaddr);
|
||
if (stubaddr == 0)
|
||
error (_("Cannot call external function not referenced by application "
|
||
"(no import stub).\n"));
|
||
regcache_cooked_write_unsigned (regcache, 22, stubaddr);
|
||
|
||
write_memory (sp, hppa32_tramp, sizeof (hppa32_tramp));
|
||
|
||
*bp_addr = hppa_hpux_find_dummy_bpaddr (pc);
|
||
regcache_cooked_write_unsigned (regcache, 31, *bp_addr);
|
||
|
||
*real_pc = hppa32_hpux_search_dummy_call_sequence (gdbarch, pc, &argreg);
|
||
if (*real_pc == 0)
|
||
error (_("Cannot make interspace call from here."));
|
||
|
||
regcache_cooked_write_unsigned (regcache, argreg, sp);
|
||
|
||
sp += sizeof (hppa32_tramp);
|
||
}
|
||
else
|
||
{
|
||
static const gdb_byte hppa64_tramp[] = {
|
||
INSN(ea,c0,f0,00), /* bve,l (r22),%r2 */
|
||
INSN(0f,df,12,d1), /* std r31,-8(,sp) */
|
||
INSN(0f,d1,10,c2), /* ldd -8(,sp),rp */
|
||
INSN(e8,40,d0,02), /* bve,n (rp) */
|
||
INSN(08,00,02,40) /* nop */
|
||
};
|
||
#undef INSN
|
||
|
||
/* for hppa64, we don't need to call through a stub; all functions
|
||
return via a bve. */
|
||
regcache_cooked_write_unsigned (regcache, 22, funcaddr);
|
||
write_memory (sp, hppa64_tramp, sizeof (hppa64_tramp));
|
||
|
||
*bp_addr = pc - 4;
|
||
regcache_cooked_write_unsigned (regcache, 31, *bp_addr);
|
||
|
||
*real_pc = hppa64_hpux_search_dummy_call_sequence (gdbarch, pc, &argreg);
|
||
if (*real_pc == 0)
|
||
error (_("Cannot make interspace call from here."));
|
||
|
||
regcache_cooked_write_unsigned (regcache, argreg, sp);
|
||
|
||
sp += sizeof (hppa64_tramp);
|
||
}
|
||
|
||
sp = gdbarch_frame_align (gdbarch, sp);
|
||
|
||
return sp;
|
||
}
|
||
|
||
|
||
|
||
static void
|
||
hppa_hpux_supply_ss_narrow (struct regcache *regcache,
|
||
int regnum, const char *save_state)
|
||
{
|
||
const char *ss_narrow = save_state + HPPA_HPUX_SS_NARROW_OFFSET;
|
||
int i, offset = 0;
|
||
|
||
for (i = HPPA_R1_REGNUM; i < HPPA_FP0_REGNUM; i++)
|
||
{
|
||
if (regnum == i || regnum == -1)
|
||
regcache_raw_supply (regcache, i, ss_narrow + offset);
|
||
|
||
offset += 4;
|
||
}
|
||
}
|
||
|
||
static void
|
||
hppa_hpux_supply_ss_fpblock (struct regcache *regcache,
|
||
int regnum, const char *save_state)
|
||
{
|
||
const char *ss_fpblock = save_state + HPPA_HPUX_SS_FPBLOCK_OFFSET;
|
||
int i, offset = 0;
|
||
|
||
/* FIXME: We view the floating-point state as 64 single-precision
|
||
registers for 32-bit code, and 32 double-precision register for
|
||
64-bit code. This distinction is artificial and should be
|
||
eliminated. If that ever happens, we should remove the if-clause
|
||
below. */
|
||
|
||
if (register_size (get_regcache_arch (regcache), HPPA_FP0_REGNUM) == 4)
|
||
{
|
||
for (i = HPPA_FP0_REGNUM; i < HPPA_FP0_REGNUM + 64; i++)
|
||
{
|
||
if (regnum == i || regnum == -1)
|
||
regcache_raw_supply (regcache, i, ss_fpblock + offset);
|
||
|
||
offset += 4;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
for (i = HPPA_FP0_REGNUM; i < HPPA_FP0_REGNUM + 32; i++)
|
||
{
|
||
if (regnum == i || regnum == -1)
|
||
regcache_raw_supply (regcache, i, ss_fpblock + offset);
|
||
|
||
offset += 8;
|
||
}
|
||
}
|
||
}
|
||
|
||
static void
|
||
hppa_hpux_supply_ss_wide (struct regcache *regcache,
|
||
int regnum, const char *save_state)
|
||
{
|
||
const char *ss_wide = save_state + HPPA_HPUX_SS_WIDE_OFFSET;
|
||
int i, offset = 8;
|
||
|
||
if (register_size (get_regcache_arch (regcache), HPPA_R1_REGNUM) == 4)
|
||
offset += 4;
|
||
|
||
for (i = HPPA_R1_REGNUM; i < HPPA_FP0_REGNUM; i++)
|
||
{
|
||
if (regnum == i || regnum == -1)
|
||
regcache_raw_supply (regcache, i, ss_wide + offset);
|
||
|
||
offset += 8;
|
||
}
|
||
}
|
||
|
||
static void
|
||
hppa_hpux_supply_save_state (const struct regset *regset,
|
||
struct regcache *regcache,
|
||
int regnum, const void *regs, size_t len)
|
||
{
|
||
struct gdbarch *gdbarch = get_regcache_arch (regcache);
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
const char *proc_info = regs;
|
||
const char *save_state = proc_info + 8;
|
||
ULONGEST flags;
|
||
|
||
flags = extract_unsigned_integer (save_state + HPPA_HPUX_SS_FLAGS_OFFSET,
|
||
4, byte_order);
|
||
if (regnum == -1 || regnum == HPPA_FLAGS_REGNUM)
|
||
{
|
||
size_t size = register_size (gdbarch, HPPA_FLAGS_REGNUM);
|
||
gdb_byte buf[8];
|
||
|
||
store_unsigned_integer (buf, size, byte_order, flags);
|
||
regcache_raw_supply (regcache, HPPA_FLAGS_REGNUM, buf);
|
||
}
|
||
|
||
/* If the SS_WIDEREGS flag is set, we really do need the full
|
||
`struct save_state'. */
|
||
if (flags & HPPA_HPUX_SS_WIDEREGS && len < HPPA_HPUX_SAVE_STATE_SIZE)
|
||
error (_("Register set contents too small"));
|
||
|
||
if (flags & HPPA_HPUX_SS_WIDEREGS)
|
||
hppa_hpux_supply_ss_wide (regcache, regnum, save_state);
|
||
else
|
||
hppa_hpux_supply_ss_narrow (regcache, regnum, save_state);
|
||
|
||
hppa_hpux_supply_ss_fpblock (regcache, regnum, save_state);
|
||
}
|
||
|
||
/* HP-UX register set. */
|
||
|
||
static struct regset hppa_hpux_regset =
|
||
{
|
||
NULL,
|
||
hppa_hpux_supply_save_state
|
||
};
|
||
|
||
static const struct regset *
|
||
hppa_hpux_regset_from_core_section (struct gdbarch *gdbarch,
|
||
const char *sect_name, size_t sect_size)
|
||
{
|
||
if (strcmp (sect_name, ".reg") == 0
|
||
&& sect_size >= HPPA_HPUX_PA89_SAVE_STATE_SIZE + 8)
|
||
return &hppa_hpux_regset;
|
||
|
||
return NULL;
|
||
}
|
||
|
||
|
||
/* Bit in the `ss_flag' member of `struct save_state' that indicates
|
||
the state was saved from a system call. From
|
||
<machine/save_state.h>. */
|
||
#define HPPA_HPUX_SS_INSYSCALL 0x02
|
||
|
||
static CORE_ADDR
|
||
hppa_hpux_read_pc (struct regcache *regcache)
|
||
{
|
||
ULONGEST flags;
|
||
|
||
/* If we're currently in a system call return the contents of %r31. */
|
||
regcache_cooked_read_unsigned (regcache, HPPA_FLAGS_REGNUM, &flags);
|
||
if (flags & HPPA_HPUX_SS_INSYSCALL)
|
||
{
|
||
ULONGEST pc;
|
||
regcache_cooked_read_unsigned (regcache, HPPA_R31_REGNUM, &pc);
|
||
return pc & ~0x3;
|
||
}
|
||
|
||
return hppa_read_pc (regcache);
|
||
}
|
||
|
||
static void
|
||
hppa_hpux_write_pc (struct regcache *regcache, CORE_ADDR pc)
|
||
{
|
||
ULONGEST flags;
|
||
|
||
/* If we're currently in a system call also write PC into %r31. */
|
||
regcache_cooked_read_unsigned (regcache, HPPA_FLAGS_REGNUM, &flags);
|
||
if (flags & HPPA_HPUX_SS_INSYSCALL)
|
||
regcache_cooked_write_unsigned (regcache, HPPA_R31_REGNUM, pc | 0x3);
|
||
|
||
hppa_write_pc (regcache, pc);
|
||
}
|
||
|
||
static CORE_ADDR
|
||
hppa_hpux_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
|
||
{
|
||
ULONGEST flags;
|
||
|
||
/* If we're currently in a system call return the contents of %r31. */
|
||
flags = frame_unwind_register_unsigned (next_frame, HPPA_FLAGS_REGNUM);
|
||
if (flags & HPPA_HPUX_SS_INSYSCALL)
|
||
return frame_unwind_register_unsigned (next_frame, HPPA_R31_REGNUM) & ~0x3;
|
||
|
||
return hppa_unwind_pc (gdbarch, next_frame);
|
||
}
|
||
|
||
|
||
/* Given the current value of the pc, check to see if it is inside a stub, and
|
||
if so, change the value of the pc to point to the caller of the stub.
|
||
THIS_FRAME is the current frame in the current list of frames.
|
||
BASE contains to stack frame base of the current frame.
|
||
SAVE_REGS is the register file stored in the frame cache. */
|
||
static void
|
||
hppa_hpux_unwind_adjust_stub (struct frame_info *this_frame, CORE_ADDR base,
|
||
struct trad_frame_saved_reg *saved_regs)
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
int word_size = gdbarch_ptr_bit (gdbarch) / 8;
|
||
struct value *pcoq_head_val;
|
||
ULONGEST pcoq_head;
|
||
CORE_ADDR stubpc;
|
||
struct unwind_table_entry *u;
|
||
|
||
pcoq_head_val = trad_frame_get_prev_register (this_frame, saved_regs,
|
||
HPPA_PCOQ_HEAD_REGNUM);
|
||
pcoq_head =
|
||
extract_unsigned_integer (value_contents_all (pcoq_head_val),
|
||
register_size (gdbarch, HPPA_PCOQ_HEAD_REGNUM),
|
||
byte_order);
|
||
|
||
u = find_unwind_entry (pcoq_head);
|
||
if (u && u->stub_unwind.stub_type == EXPORT)
|
||
{
|
||
stubpc = read_memory_integer (base - 24, word_size, byte_order);
|
||
trad_frame_set_value (saved_regs, HPPA_PCOQ_HEAD_REGNUM, stubpc);
|
||
}
|
||
else if (hppa_symbol_address ("__gcc_plt_call")
|
||
== get_pc_function_start (pcoq_head))
|
||
{
|
||
stubpc = read_memory_integer (base - 8, word_size, byte_order);
|
||
trad_frame_set_value (saved_regs, HPPA_PCOQ_HEAD_REGNUM, stubpc);
|
||
}
|
||
}
|
||
|
||
static void
|
||
hppa_hpux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
|
||
if (IS_32BIT_TARGET (gdbarch))
|
||
tdep->in_solib_call_trampoline = hppa32_hpux_in_solib_call_trampoline;
|
||
else
|
||
tdep->in_solib_call_trampoline = hppa64_hpux_in_solib_call_trampoline;
|
||
|
||
tdep->unwind_adjust_stub = hppa_hpux_unwind_adjust_stub;
|
||
|
||
set_gdbarch_in_solib_return_trampoline
|
||
(gdbarch, hppa_hpux_in_solib_return_trampoline);
|
||
set_gdbarch_skip_trampoline_code (gdbarch, hppa_hpux_skip_trampoline_code);
|
||
|
||
set_gdbarch_push_dummy_code (gdbarch, hppa_hpux_push_dummy_code);
|
||
set_gdbarch_call_dummy_location (gdbarch, ON_STACK);
|
||
|
||
set_gdbarch_read_pc (gdbarch, hppa_hpux_read_pc);
|
||
set_gdbarch_write_pc (gdbarch, hppa_hpux_write_pc);
|
||
set_gdbarch_unwind_pc (gdbarch, hppa_hpux_unwind_pc);
|
||
set_gdbarch_skip_permanent_breakpoint
|
||
(gdbarch, hppa_skip_permanent_breakpoint);
|
||
|
||
set_gdbarch_regset_from_core_section
|
||
(gdbarch, hppa_hpux_regset_from_core_section);
|
||
|
||
frame_unwind_append_unwinder (gdbarch, &hppa_hpux_sigtramp_frame_unwind);
|
||
}
|
||
|
||
static void
|
||
hppa_hpux_som_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
|
||
tdep->is_elf = 0;
|
||
|
||
tdep->find_global_pointer = hppa32_hpux_find_global_pointer;
|
||
|
||
hppa_hpux_init_abi (info, gdbarch);
|
||
som_solib_select (gdbarch);
|
||
}
|
||
|
||
static void
|
||
hppa_hpux_elf_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
|
||
tdep->is_elf = 1;
|
||
tdep->find_global_pointer = hppa64_hpux_find_global_pointer;
|
||
|
||
hppa_hpux_init_abi (info, gdbarch);
|
||
pa64_solib_select (gdbarch);
|
||
}
|
||
|
||
static enum gdb_osabi
|
||
hppa_hpux_core_osabi_sniffer (bfd *abfd)
|
||
{
|
||
if (strcmp (bfd_get_target (abfd), "hpux-core") == 0)
|
||
return GDB_OSABI_HPUX_SOM;
|
||
else if (strcmp (bfd_get_target (abfd), "elf64-hppa") == 0)
|
||
{
|
||
asection *section;
|
||
|
||
section = bfd_get_section_by_name (abfd, ".kernel");
|
||
if (section)
|
||
{
|
||
bfd_size_type size;
|
||
char *contents;
|
||
|
||
size = bfd_section_size (abfd, section);
|
||
contents = alloca (size);
|
||
if (bfd_get_section_contents (abfd, section, contents,
|
||
(file_ptr) 0, size)
|
||
&& strcmp (contents, "HP-UX") == 0)
|
||
return GDB_OSABI_HPUX_ELF;
|
||
}
|
||
}
|
||
|
||
return GDB_OSABI_UNKNOWN;
|
||
}
|
||
|
||
void
|
||
_initialize_hppa_hpux_tdep (void)
|
||
{
|
||
/* BFD doesn't set a flavour for HP-UX style core files. It doesn't
|
||
set the architecture either. */
|
||
gdbarch_register_osabi_sniffer (bfd_arch_unknown,
|
||
bfd_target_unknown_flavour,
|
||
hppa_hpux_core_osabi_sniffer);
|
||
gdbarch_register_osabi_sniffer (bfd_arch_hppa,
|
||
bfd_target_elf_flavour,
|
||
hppa_hpux_core_osabi_sniffer);
|
||
|
||
gdbarch_register_osabi (bfd_arch_hppa, 0, GDB_OSABI_HPUX_SOM,
|
||
hppa_hpux_som_init_abi);
|
||
gdbarch_register_osabi (bfd_arch_hppa, bfd_mach_hppa20w, GDB_OSABI_HPUX_ELF,
|
||
hppa_hpux_elf_init_abi);
|
||
}
|