541 lines
15 KiB
C
541 lines
15 KiB
C
/* Target-dependent code for GNU/Linux running on PA-RISC, for GDB.
|
||
|
||
Copyright (C) 2004-2017 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 "gdbcore.h"
|
||
#include "osabi.h"
|
||
#include "target.h"
|
||
#include "objfiles.h"
|
||
#include "solib-svr4.h"
|
||
#include "glibc-tdep.h"
|
||
#include "frame-unwind.h"
|
||
#include "trad-frame.h"
|
||
#include "dwarf2-frame.h"
|
||
#include "value.h"
|
||
#include "regset.h"
|
||
#include "regcache.h"
|
||
#include "hppa-tdep.h"
|
||
#include "linux-tdep.h"
|
||
#include "elf/common.h"
|
||
|
||
/* Map DWARF DBX register numbers to GDB register numbers. */
|
||
static int
|
||
hppa_dwarf_reg_to_regnum (struct gdbarch *gdbarch, int reg)
|
||
{
|
||
/* The general registers and the sar are the same in both sets. */
|
||
if (reg >= 0 && reg <= 32)
|
||
return reg;
|
||
|
||
/* fr4-fr31 (left and right halves) are mapped from 72. */
|
||
if (reg >= 72 && reg <= 72 + 28 * 2)
|
||
return HPPA_FP4_REGNUM + (reg - 72);
|
||
|
||
return -1;
|
||
}
|
||
|
||
static void
|
||
hppa_linux_target_write_pc (struct regcache *regcache, CORE_ADDR v)
|
||
{
|
||
/* Probably this should be done by the kernel, but it isn't. */
|
||
regcache_cooked_write_unsigned (regcache, HPPA_PCOQ_HEAD_REGNUM, v | 0x3);
|
||
regcache_cooked_write_unsigned (regcache,
|
||
HPPA_PCOQ_TAIL_REGNUM, (v + 4) | 0x3);
|
||
}
|
||
|
||
/* An instruction to match. */
|
||
struct insn_pattern
|
||
{
|
||
unsigned int data; /* See if it matches this.... */
|
||
unsigned int mask; /* ... with this mask. */
|
||
};
|
||
|
||
static struct insn_pattern hppa_sigtramp[] = {
|
||
/* ldi 0, %r25 or ldi 1, %r25 */
|
||
{ 0x34190000, 0xfffffffd },
|
||
/* ldi __NR_rt_sigreturn, %r20 */
|
||
{ 0x3414015a, 0xffffffff },
|
||
/* be,l 0x100(%sr2, %r0), %sr0, %r31 */
|
||
{ 0xe4008200, 0xffffffff },
|
||
/* nop */
|
||
{ 0x08000240, 0xffffffff },
|
||
{ 0, 0 }
|
||
};
|
||
|
||
#define HPPA_MAX_INSN_PATTERN_LEN (4)
|
||
|
||
/* Return non-zero if the instructions at PC match the series
|
||
described in PATTERN, or zero otherwise. PATTERN is an array of
|
||
'struct insn_pattern' objects, terminated by an entry whose mask is
|
||
zero.
|
||
|
||
When the match is successful, fill INSN[i] with what PATTERN[i]
|
||
matched. */
|
||
static int
|
||
insns_match_pattern (struct gdbarch *gdbarch, CORE_ADDR pc,
|
||
struct insn_pattern *pattern,
|
||
unsigned int *insn)
|
||
{
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
int i;
|
||
CORE_ADDR npc = pc;
|
||
|
||
for (i = 0; pattern[i].mask; i++)
|
||
{
|
||
gdb_byte buf[4];
|
||
|
||
target_read_memory (npc, buf, 4);
|
||
insn[i] = extract_unsigned_integer (buf, 4, byte_order);
|
||
if ((insn[i] & pattern[i].mask) == pattern[i].data)
|
||
npc += 4;
|
||
else
|
||
return 0;
|
||
}
|
||
return 1;
|
||
}
|
||
|
||
/* Signal frames. */
|
||
|
||
/* (This is derived from MD_FALLBACK_FRAME_STATE_FOR in gcc.)
|
||
|
||
Unfortunately, because of various bugs and changes to the kernel,
|
||
we have several cases to deal with.
|
||
|
||
In 2.4, the signal trampoline is 4 bytes, and pc should point directly at
|
||
the beginning of the trampoline and struct rt_sigframe.
|
||
|
||
In <= 2.6.5-rc2-pa3, the signal trampoline is 9 bytes, and pc points at
|
||
the 4th word in the trampoline structure. This is wrong, it should point
|
||
at the 5th word. This is fixed in 2.6.5-rc2-pa4.
|
||
|
||
To detect these cases, we first take pc, align it to 64-bytes
|
||
to get the beginning of the signal frame, and then check offsets 0, 4
|
||
and 5 to see if we found the beginning of the trampoline. This will
|
||
tell us how to locate the sigcontext structure.
|
||
|
||
Note that with a 2.4 64-bit kernel, the signal context is not properly
|
||
passed back to userspace so the unwind will not work correctly. */
|
||
static CORE_ADDR
|
||
hppa_linux_sigtramp_find_sigcontext (struct gdbarch *gdbarch, CORE_ADDR pc)
|
||
{
|
||
unsigned int dummy[HPPA_MAX_INSN_PATTERN_LEN];
|
||
int offs = 0;
|
||
int attempt;
|
||
/* offsets to try to find the trampoline */
|
||
static int pcoffs[] = { 0, 4*4, 5*4 };
|
||
/* offsets to the rt_sigframe structure */
|
||
static int sfoffs[] = { 4*4, 10*4, 10*4 };
|
||
CORE_ADDR sp;
|
||
|
||
/* Most of the time, this will be correct. The one case when this will
|
||
fail is if the user defined an alternate stack, in which case the
|
||
beginning of the stack will not be align_down (pc, 64). */
|
||
sp = align_down (pc, 64);
|
||
|
||
/* rt_sigreturn trampoline:
|
||
3419000x ldi 0, %r25 or ldi 1, %r25 (x = 0 or 2)
|
||
3414015a ldi __NR_rt_sigreturn, %r20
|
||
e4008200 be,l 0x100(%sr2, %r0), %sr0, %r31
|
||
08000240 nop */
|
||
|
||
for (attempt = 0; attempt < ARRAY_SIZE (pcoffs); attempt++)
|
||
{
|
||
if (insns_match_pattern (gdbarch, sp + pcoffs[attempt],
|
||
hppa_sigtramp, dummy))
|
||
{
|
||
offs = sfoffs[attempt];
|
||
break;
|
||
}
|
||
}
|
||
|
||
if (offs == 0)
|
||
{
|
||
if (insns_match_pattern (gdbarch, pc, hppa_sigtramp, dummy))
|
||
{
|
||
/* sigaltstack case: we have no way of knowing which offset to
|
||
use in this case; default to new kernel handling. If this is
|
||
wrong the unwinding will fail. */
|
||
attempt = 2;
|
||
sp = pc - pcoffs[attempt];
|
||
}
|
||
else
|
||
{
|
||
return 0;
|
||
}
|
||
}
|
||
|
||
/* sp + sfoffs[try] points to a struct rt_sigframe, which contains
|
||
a struct siginfo and a struct ucontext. struct ucontext contains
|
||
a struct sigcontext. Return an offset to this sigcontext here. Too
|
||
bad we cannot include system specific headers :-(.
|
||
sizeof(struct siginfo) == 128
|
||
offsetof(struct ucontext, uc_mcontext) == 24. */
|
||
return sp + sfoffs[attempt] + 128 + 24;
|
||
}
|
||
|
||
struct hppa_linux_sigtramp_unwind_cache
|
||
{
|
||
CORE_ADDR base;
|
||
struct trad_frame_saved_reg *saved_regs;
|
||
};
|
||
|
||
static struct hppa_linux_sigtramp_unwind_cache *
|
||
hppa_linux_sigtramp_frame_unwind_cache (struct frame_info *this_frame,
|
||
void **this_cache)
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
||
struct hppa_linux_sigtramp_unwind_cache *info;
|
||
CORE_ADDR pc, scptr;
|
||
int i;
|
||
|
||
if (*this_cache)
|
||
return (struct hppa_linux_sigtramp_unwind_cache *) *this_cache;
|
||
|
||
info = FRAME_OBSTACK_ZALLOC (struct hppa_linux_sigtramp_unwind_cache);
|
||
*this_cache = info;
|
||
info->saved_regs = trad_frame_alloc_saved_regs (this_frame);
|
||
|
||
pc = get_frame_pc (this_frame);
|
||
scptr = hppa_linux_sigtramp_find_sigcontext (gdbarch, pc);
|
||
|
||
/* structure of struct sigcontext:
|
||
|
||
struct sigcontext {
|
||
unsigned long sc_flags;
|
||
unsigned long sc_gr[32];
|
||
unsigned long long sc_fr[32];
|
||
unsigned long sc_iasq[2];
|
||
unsigned long sc_iaoq[2];
|
||
unsigned long sc_sar; */
|
||
|
||
/* Skip sc_flags. */
|
||
scptr += 4;
|
||
|
||
/* GR[0] is the psw. */
|
||
info->saved_regs[HPPA_IPSW_REGNUM].addr = scptr;
|
||
scptr += 4;
|
||
|
||
/* General registers. */
|
||
for (i = 1; i < 32; i++)
|
||
{
|
||
info->saved_regs[HPPA_R0_REGNUM + i].addr = scptr;
|
||
scptr += 4;
|
||
}
|
||
|
||
/* Pad to long long boundary. */
|
||
scptr += 4;
|
||
|
||
/* FP regs; FP0-3 are not restored. */
|
||
scptr += (8 * 4);
|
||
|
||
for (i = 4; i < 32; i++)
|
||
{
|
||
info->saved_regs[HPPA_FP0_REGNUM + (i * 2)].addr = scptr;
|
||
scptr += 4;
|
||
info->saved_regs[HPPA_FP0_REGNUM + (i * 2) + 1].addr = scptr;
|
||
scptr += 4;
|
||
}
|
||
|
||
/* IASQ/IAOQ. */
|
||
info->saved_regs[HPPA_PCSQ_HEAD_REGNUM].addr = scptr;
|
||
scptr += 4;
|
||
info->saved_regs[HPPA_PCSQ_TAIL_REGNUM].addr = scptr;
|
||
scptr += 4;
|
||
|
||
info->saved_regs[HPPA_PCOQ_HEAD_REGNUM].addr = scptr;
|
||
scptr += 4;
|
||
info->saved_regs[HPPA_PCOQ_TAIL_REGNUM].addr = scptr;
|
||
scptr += 4;
|
||
|
||
info->saved_regs[HPPA_SAR_REGNUM].addr = scptr;
|
||
|
||
info->base = get_frame_register_unsigned (this_frame, HPPA_SP_REGNUM);
|
||
|
||
return info;
|
||
}
|
||
|
||
static void
|
||
hppa_linux_sigtramp_frame_this_id (struct frame_info *this_frame,
|
||
void **this_prologue_cache,
|
||
struct frame_id *this_id)
|
||
{
|
||
struct hppa_linux_sigtramp_unwind_cache *info
|
||
= hppa_linux_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_linux_sigtramp_frame_prev_register (struct frame_info *this_frame,
|
||
void **this_prologue_cache,
|
||
int regnum)
|
||
{
|
||
struct hppa_linux_sigtramp_unwind_cache *info
|
||
= hppa_linux_sigtramp_frame_unwind_cache (this_frame, this_prologue_cache);
|
||
return hppa_frame_prev_register_helper (this_frame,
|
||
info->saved_regs, regnum);
|
||
}
|
||
|
||
/* hppa-linux always uses "new-style" rt-signals. The signal handler's return
|
||
address should point to a signal trampoline on the stack. The signal
|
||
trampoline is embedded in a rt_sigframe structure that is aligned on
|
||
the stack. We take advantage of the fact that sp must be 64-byte aligned,
|
||
and the trampoline is small, so by rounding down the trampoline address
|
||
we can find the beginning of the struct rt_sigframe. */
|
||
static int
|
||
hppa_linux_sigtramp_frame_sniffer (const struct frame_unwind *self,
|
||
struct frame_info *this_frame,
|
||
void **this_prologue_cache)
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
||
CORE_ADDR pc = get_frame_pc (this_frame);
|
||
|
||
if (hppa_linux_sigtramp_find_sigcontext (gdbarch, pc))
|
||
return 1;
|
||
|
||
return 0;
|
||
}
|
||
|
||
static const struct frame_unwind hppa_linux_sigtramp_frame_unwind = {
|
||
SIGTRAMP_FRAME,
|
||
default_frame_unwind_stop_reason,
|
||
hppa_linux_sigtramp_frame_this_id,
|
||
hppa_linux_sigtramp_frame_prev_register,
|
||
NULL,
|
||
hppa_linux_sigtramp_frame_sniffer
|
||
};
|
||
|
||
/* Attempt to find (and return) the global pointer for the given
|
||
function.
|
||
|
||
This is a rather nasty bit of code searchs for the .dynamic section
|
||
in the objfile corresponding to the pc of the function we're trying
|
||
to call. Once it finds the addresses at which the .dynamic section
|
||
lives in the child process, it scans the Elf32_Dyn entries for a
|
||
DT_PLTGOT tag. If it finds one of these, the corresponding
|
||
d_un.d_ptr value is the global pointer. */
|
||
|
||
static CORE_ADDR
|
||
hppa_linux_find_global_pointer (struct gdbarch *gdbarch,
|
||
struct value *function)
|
||
{
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
struct obj_section *faddr_sect;
|
||
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);
|
||
}
|
||
|
||
/* If the address is in the plt section, then the real function hasn't
|
||
yet been fixed up by the linker so we cannot determine the gp of
|
||
that function. */
|
||
if (in_plt_section (faddr))
|
||
return 0;
|
||
|
||
faddr_sect = find_pc_section (faddr);
|
||
if (faddr_sect != NULL)
|
||
{
|
||
struct obj_section *osect;
|
||
|
||
ALL_OBJFILE_OSECTIONS (faddr_sect->objfile, osect)
|
||
{
|
||
if (strcmp (osect->the_bfd_section->name, ".dynamic") == 0)
|
||
break;
|
||
}
|
||
|
||
if (osect < faddr_sect->objfile->sections_end)
|
||
{
|
||
CORE_ADDR addr, endaddr;
|
||
|
||
addr = obj_section_addr (osect);
|
||
endaddr = obj_section_endaddr (osect);
|
||
|
||
while (addr < endaddr)
|
||
{
|
||
int status;
|
||
LONGEST tag;
|
||
gdb_byte buf[4];
|
||
|
||
status = target_read_memory (addr, buf, sizeof (buf));
|
||
if (status != 0)
|
||
break;
|
||
tag = extract_signed_integer (buf, sizeof (buf), byte_order);
|
||
|
||
if (tag == DT_PLTGOT)
|
||
{
|
||
CORE_ADDR global_pointer;
|
||
|
||
status = target_read_memory (addr + 4, buf, sizeof (buf));
|
||
if (status != 0)
|
||
break;
|
||
global_pointer = extract_unsigned_integer (buf, sizeof (buf),
|
||
byte_order);
|
||
/* The payoff... */
|
||
return global_pointer;
|
||
}
|
||
|
||
if (tag == DT_NULL)
|
||
break;
|
||
|
||
addr += 8;
|
||
}
|
||
}
|
||
}
|
||
return 0;
|
||
}
|
||
|
||
/*
|
||
* Registers saved in a coredump:
|
||
* gr0..gr31
|
||
* sr0..sr7
|
||
* iaoq0..iaoq1
|
||
* iasq0..iasq1
|
||
* sar, iir, isr, ior, ipsw
|
||
* cr0, cr24..cr31
|
||
* cr8,9,12,13
|
||
* cr10, cr15
|
||
*/
|
||
|
||
static const struct regcache_map_entry hppa_linux_gregmap[] =
|
||
{
|
||
{ 32, HPPA_R0_REGNUM },
|
||
{ 1, HPPA_SR4_REGNUM+1 },
|
||
{ 1, HPPA_SR4_REGNUM+2 },
|
||
{ 1, HPPA_SR4_REGNUM+3 },
|
||
{ 1, HPPA_SR4_REGNUM+4 },
|
||
{ 1, HPPA_SR4_REGNUM },
|
||
{ 1, HPPA_SR4_REGNUM+5 },
|
||
{ 1, HPPA_SR4_REGNUM+6 },
|
||
{ 1, HPPA_SR4_REGNUM+7 },
|
||
{ 1, HPPA_PCOQ_HEAD_REGNUM },
|
||
{ 1, HPPA_PCOQ_TAIL_REGNUM },
|
||
{ 1, HPPA_PCSQ_HEAD_REGNUM },
|
||
{ 1, HPPA_PCSQ_TAIL_REGNUM },
|
||
{ 1, HPPA_SAR_REGNUM },
|
||
{ 1, HPPA_IIR_REGNUM },
|
||
{ 1, HPPA_ISR_REGNUM },
|
||
{ 1, HPPA_IOR_REGNUM },
|
||
{ 1, HPPA_IPSW_REGNUM },
|
||
{ 1, HPPA_RCR_REGNUM },
|
||
{ 8, HPPA_TR0_REGNUM },
|
||
{ 4, HPPA_PID0_REGNUM },
|
||
{ 1, HPPA_CCR_REGNUM },
|
||
{ 1, HPPA_EIEM_REGNUM },
|
||
{ 0 }
|
||
};
|
||
|
||
static const struct regcache_map_entry hppa_linux_fpregmap[] =
|
||
{
|
||
/* FIXME: Only works for 32-bit mode. In 64-bit mode there should
|
||
be 32 fpregs, 8 bytes each. */
|
||
{ 64, HPPA_FP0_REGNUM, 4 },
|
||
{ 0 }
|
||
};
|
||
|
||
/* HPPA Linux kernel register set. */
|
||
static const struct regset hppa_linux_regset =
|
||
{
|
||
hppa_linux_gregmap,
|
||
regcache_supply_regset, regcache_collect_regset
|
||
};
|
||
|
||
static const struct regset hppa_linux_fpregset =
|
||
{
|
||
hppa_linux_fpregmap,
|
||
regcache_supply_regset, regcache_collect_regset
|
||
};
|
||
|
||
static void
|
||
hppa_linux_iterate_over_regset_sections (struct gdbarch *gdbarch,
|
||
iterate_over_regset_sections_cb *cb,
|
||
void *cb_data,
|
||
const struct regcache *regcache)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
|
||
cb (".reg", 80 * tdep->bytes_per_address, &hppa_linux_regset,
|
||
NULL, cb_data);
|
||
cb (".reg2", 64 * 4, &hppa_linux_fpregset, NULL, cb_data);
|
||
}
|
||
|
||
|
||
/* Forward declarations. */
|
||
extern initialize_file_ftype _initialize_hppa_linux_tdep;
|
||
|
||
static void
|
||
hppa_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
|
||
linux_init_abi (info, gdbarch);
|
||
|
||
/* GNU/Linux is always ELF. */
|
||
tdep->is_elf = 1;
|
||
|
||
tdep->find_global_pointer = hppa_linux_find_global_pointer;
|
||
|
||
set_gdbarch_write_pc (gdbarch, hppa_linux_target_write_pc);
|
||
|
||
frame_unwind_append_unwinder (gdbarch, &hppa_linux_sigtramp_frame_unwind);
|
||
|
||
/* GNU/Linux uses SVR4-style shared libraries. */
|
||
set_solib_svr4_fetch_link_map_offsets
|
||
(gdbarch, svr4_ilp32_fetch_link_map_offsets);
|
||
|
||
tdep->in_solib_call_trampoline = hppa_in_solib_call_trampoline;
|
||
set_gdbarch_skip_trampoline_code (gdbarch, hppa_skip_trampoline_code);
|
||
|
||
/* GNU/Linux uses the dynamic linker included in the GNU C Library. */
|
||
set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver);
|
||
|
||
/* On hppa-linux, currently, sizeof(long double) == 8. There has been
|
||
some discussions to support 128-bit long double, but it requires some
|
||
more work in gcc and glibc first. */
|
||
set_gdbarch_long_double_bit (gdbarch, 64);
|
||
set_gdbarch_long_double_format (gdbarch, floatformats_ieee_double);
|
||
|
||
set_gdbarch_iterate_over_regset_sections
|
||
(gdbarch, hppa_linux_iterate_over_regset_sections);
|
||
|
||
set_gdbarch_dwarf2_reg_to_regnum (gdbarch, hppa_dwarf_reg_to_regnum);
|
||
|
||
/* Enable TLS support. */
|
||
set_gdbarch_fetch_tls_load_module_address (gdbarch,
|
||
svr4_fetch_objfile_link_map);
|
||
}
|
||
|
||
void
|
||
_initialize_hppa_linux_tdep (void)
|
||
{
|
||
gdbarch_register_osabi (bfd_arch_hppa, 0, GDB_OSABI_LINUX,
|
||
hppa_linux_init_abi);
|
||
gdbarch_register_osabi (bfd_arch_hppa, bfd_mach_hppa20w,
|
||
GDB_OSABI_LINUX, hppa_linux_init_abi);
|
||
}
|