/* Target-dependent code for OpenBSD/powerpc.
- Copyright 2004 Free Software Foundation, Inc.
+ Copyright (C) 2004-2016 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 2 of the License, or
+ 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,
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, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "arch-utils.h"
+#include "frame.h"
+#include "frame-unwind.h"
+#include "gdbtypes.h"
#include "osabi.h"
#include "regcache.h"
#include "regset.h"
-#include "gdb_assert.h"
-
-#include "gdb_string.h"
+#include "symtab.h"
+#include "trad-frame.h"
#include "ppc-tdep.h"
#include "ppcobsd-tdep.h"
/* Register offsets from <machine/reg.h>. */
struct ppc_reg_offsets ppcobsd_reg_offsets;
+struct ppc_reg_offsets ppcobsd_fpreg_offsets;
\f
/* Core file support. */
struct regcache *regcache, int regnum,
const void *gregs, size_t len)
{
- /* FIXME: jimb/2004-05-05: Some PPC variants don't have floating
- point registers. Traditionally, GDB's register set has still
- listed the floating point registers for such machines, so this
- code is harmless. However, the new E500 port actually omits the
- floating point registers entirely from the register set --- they
- don't even have register numbers assigned to them.
-
- It's not clear to me how best to update this code, so this assert
- will alert the first person to encounter the OpenBSD/E500
- combination to the problem. */
- gdb_assert (ppc_floating_point_unit_p (current_gdbarch));
-
ppc_supply_gregset (regset, regcache, regnum, gregs, len);
ppc_supply_fpregset (regset, regcache, regnum, gregs, len);
}
/* Collect register REGNUM in the general-purpose register set
- REGSET. from register cache REGCACHE into the buffer specified by
+ REGSET, from register cache REGCACHE into the buffer specified by
GREGS and LEN. If REGNUM is -1, do this for all registers in
REGSET. */
const struct regcache *regcache, int regnum,
void *gregs, size_t len)
{
- /* FIXME: jimb/2004-05-05: Some PPC variants don't have floating
- point registers. Traditionally, GDB's register set has still
- listed the floating point registers for such machines, so this
- code is harmless. However, the new E500 port actually omits the
- floating point registers entirely from the register set --- they
- don't even have register numbers assigned to them.
-
- It's not clear to me how best to update this code, so this assert
- will alert the first person to encounter the OpenBSD/E500
- combination to the problem. */
- gdb_assert (ppc_floating_point_unit_p (current_gdbarch));
-
ppc_collect_gregset (regset, regcache, regnum, gregs, len);
ppc_collect_fpregset (regset, regcache, regnum, gregs, len);
}
-/* OpenBS/powerpc register set. */
+/* OpenBSD/powerpc register set. */
-struct regset ppcobsd_gregset =
+const struct regset ppcobsd_gregset =
{
&ppcobsd_reg_offsets,
ppcobsd_supply_gregset
};
-/* Return the appropriate register set for the core section identified
- by SECT_NAME and SECT_SIZE. */
+const struct regset ppcobsd_fpregset =
+{
+ &ppcobsd_fpreg_offsets,
+ ppc_supply_fpregset
+};
+
+/* Iterate over core file register note sections. */
+
+static void
+ppcobsd_iterate_over_regset_sections (struct gdbarch *gdbarch,
+ iterate_over_regset_sections_cb *cb,
+ void *cb_data,
+ const struct regcache *regcache)
+{
+ cb (".reg", 412, &ppcobsd_gregset, NULL, cb_data);
+}
+\f
+
+/* Signal trampolines. */
-static const struct regset *
-ppcobsd_regset_from_core_section (struct gdbarch *gdbarch,
- const char *sect_name, size_t sect_size)
+/* Since OpenBSD 3.2, the sigtramp routine is mapped at a random page
+ in virtual memory. The randomness makes it somewhat tricky to
+ detect it, but fortunately we can rely on the fact that the start
+ of the sigtramp routine is page-aligned. We recognize the
+ trampoline by looking for the code that invokes the sigreturn
+ system call. The offset where we can find that code varies from
+ release to release.
+
+ By the way, the mapping mentioned above is read-only, so you cannot
+ place a breakpoint in the signal trampoline. */
+
+/* Default page size. */
+static const int ppcobsd_page_size = 4096;
+
+/* Offset for sigreturn(2). */
+static const int ppcobsd_sigreturn_offset[] = {
+ 0x98, /* OpenBSD 3.8 */
+ 0x0c, /* OpenBSD 3.2 */
+ -1
+};
+
+static int
+ppcobsd_sigtramp_frame_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame,
+ void **this_cache)
{
- if (strcmp (sect_name, ".reg") == 0 && sect_size >= 412)
- return &ppcobsd_gregset;
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ CORE_ADDR pc = get_frame_pc (this_frame);
+ CORE_ADDR start_pc = (pc & ~(ppcobsd_page_size - 1));
+ const int *offset;
+ const char *name;
+
+ find_pc_partial_function (pc, &name, NULL, NULL);
+ if (name)
+ return 0;
+
+ for (offset = ppcobsd_sigreturn_offset; *offset != -1; offset++)
+ {
+ gdb_byte buf[2 * PPC_INSN_SIZE];
+ unsigned long insn;
- return NULL;
+ if (!safe_frame_unwind_memory (this_frame, start_pc + *offset,
+ buf, sizeof buf))
+ continue;
+
+ /* Check for "li r0,SYS_sigreturn". */
+ insn = extract_unsigned_integer (buf, PPC_INSN_SIZE, byte_order);
+ if (insn != 0x38000067)
+ continue;
+
+ /* Check for "sc". */
+ insn = extract_unsigned_integer (buf + PPC_INSN_SIZE,
+ PPC_INSN_SIZE, byte_order);
+ if (insn != 0x44000002)
+ continue;
+
+ return 1;
+ }
+
+ return 0;
}
+
+static struct trad_frame_cache *
+ppcobsd_sigtramp_frame_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 trad_frame_cache *cache;
+ CORE_ADDR addr, base, func;
+ gdb_byte buf[PPC_INSN_SIZE];
+ unsigned long insn, sigcontext_offset;
+ int i;
+
+ if (*this_cache)
+ return (struct trad_frame_cache *) *this_cache;
+
+ cache = trad_frame_cache_zalloc (this_frame);
+ *this_cache = cache;
+
+ func = get_frame_pc (this_frame);
+ func &= ~(ppcobsd_page_size - 1);
+ if (!safe_frame_unwind_memory (this_frame, func, buf, sizeof buf))
+ return cache;
+
+ /* Calculate the offset where we can find `struct sigcontext'. We
+ base our calculation on the amount of stack space reserved by the
+ first instruction of the signal trampoline. */
+ insn = extract_unsigned_integer (buf, PPC_INSN_SIZE, byte_order);
+ sigcontext_offset = (0x10000 - (insn & 0x0000ffff)) + 8;
+
+ base = get_frame_register_unsigned (this_frame, gdbarch_sp_regnum (gdbarch));
+ addr = base + sigcontext_offset + 2 * tdep->wordsize;
+ for (i = 0; i < ppc_num_gprs; i++, addr += tdep->wordsize)
+ {
+ int regnum = i + tdep->ppc_gp0_regnum;
+ trad_frame_set_reg_addr (cache, regnum, addr);
+ }
+ trad_frame_set_reg_addr (cache, tdep->ppc_lr_regnum, addr);
+ addr += tdep->wordsize;
+ trad_frame_set_reg_addr (cache, tdep->ppc_cr_regnum, addr);
+ addr += tdep->wordsize;
+ trad_frame_set_reg_addr (cache, tdep->ppc_xer_regnum, addr);
+ addr += tdep->wordsize;
+ trad_frame_set_reg_addr (cache, tdep->ppc_ctr_regnum, addr);
+ addr += tdep->wordsize;
+ trad_frame_set_reg_addr (cache, gdbarch_pc_regnum (gdbarch), addr);
+ /* SRR0? */
+ addr += tdep->wordsize;
+
+ /* Construct the frame ID using the function start. */
+ trad_frame_set_id (cache, frame_id_build (base, func));
+
+ return cache;
+}
+
+static void
+ppcobsd_sigtramp_frame_this_id (struct frame_info *this_frame,
+ void **this_cache, struct frame_id *this_id)
+{
+ struct trad_frame_cache *cache =
+ ppcobsd_sigtramp_frame_cache (this_frame, this_cache);
+
+ trad_frame_get_id (cache, this_id);
+}
+
+static struct value *
+ppcobsd_sigtramp_frame_prev_register (struct frame_info *this_frame,
+ void **this_cache, int regnum)
+{
+ struct trad_frame_cache *cache =
+ ppcobsd_sigtramp_frame_cache (this_frame, this_cache);
+
+ return trad_frame_get_register (cache, this_frame, regnum);
+}
+
+static const struct frame_unwind ppcobsd_sigtramp_frame_unwind = {
+ SIGTRAMP_FRAME,
+ default_frame_unwind_stop_reason,
+ ppcobsd_sigtramp_frame_this_id,
+ ppcobsd_sigtramp_frame_prev_register,
+ NULL,
+ ppcobsd_sigtramp_frame_sniffer
+};
\f
static void
ppcobsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
+ /* OpenBSD doesn't support the 128-bit `long double' from the psABI. */
+ set_gdbarch_long_double_bit (gdbarch, 64);
+ set_gdbarch_long_double_format (gdbarch, floatformats_ieee_double);
+
+ /* OpenBSD currently uses a broken GCC. */
+ set_gdbarch_return_value (gdbarch, ppc_sysv_abi_broken_return_value);
+
/* OpenBSD uses SVR4-style shared libraries. */
set_solib_svr4_fetch_link_map_offsets
(gdbarch, svr4_ilp32_fetch_link_map_offsets);
- set_gdbarch_regset_from_core_section
- (gdbarch, ppcobsd_regset_from_core_section);
+ set_gdbarch_iterate_over_regset_sections
+ (gdbarch, ppcobsd_iterate_over_regset_sections);
+
+ frame_unwind_append_unwinder (gdbarch, &ppcobsd_sigtramp_frame_unwind);
}
\f
gdbarch_register_osabi_sniffer (bfd_arch_powerpc, bfd_target_unknown_flavour,
ppcobsd_core_osabi_sniffer);
+ gdbarch_register_osabi (bfd_arch_rs6000, 0, GDB_OSABI_OPENBSD_ELF,
+ ppcobsd_init_abi);
gdbarch_register_osabi (bfd_arch_powerpc, 0, GDB_OSABI_OPENBSD_ELF,
ppcobsd_init_abi);
{
/* General-purpose registers. */
ppcobsd_reg_offsets.r0_offset = 0;
+ ppcobsd_reg_offsets.gpr_size = 4;
+ ppcobsd_reg_offsets.xr_size = 4;
ppcobsd_reg_offsets.pc_offset = 384;
ppcobsd_reg_offsets.ps_offset = 388;
ppcobsd_reg_offsets.cr_offset = 392;
ppcobsd_reg_offsets.vscr_offset = 512;
ppcobsd_reg_offsets.vrsave_offset = 520;
}
+
+ if (ppcobsd_fpreg_offsets.fpscr_offset == 0)
+ {
+ /* Floating-point registers. */
+ ppcobsd_reg_offsets.f0_offset = 0;
+ ppcobsd_reg_offsets.fpscr_offset = 256;
+ ppcobsd_reg_offsets.fpscr_size = 4;
+ }
}
projects / deliverable / binutils-gdb.git / blobdiff