/* Target-dependent code for OpenBSD/amd64.
- Copyright 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
This file is part of GDB.
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. */
+ Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA. */
#include "defs.h"
#include "frame.h"
+#include "frame-unwind.h"
#include "gdbcore.h"
+#include "symtab.h"
+#include "objfiles.h"
#include "osabi.h"
+#include "regcache.h"
#include "regset.h"
#include "target.h"
+#include "trad-frame.h"
#include "gdb_assert.h"
#include "gdb_string.h"
#include "amd64-tdep.h"
#include "i387-tdep.h"
#include "solib-svr4.h"
+#include "bsd-uthread.h"
/* Support for core dumps. */
struct regcache *regcache, int regnum,
const void *regs, size_t len)
{
- const struct gdbarch_tdep *tdep = regset->descr;
+ const struct gdbarch_tdep *tdep = gdbarch_tdep (regset->arch);
gdb_assert (len >= tdep->sizeof_gregset + I387_SIZEOF_FXSAVE);
i386_supply_gregset (regset, regcache, regnum, regs, tdep->sizeof_gregset);
- amd64_supply_fxsave (regcache, regnum, (char *)regs + tdep->sizeof_gregset);
+ amd64_supply_fxsave (regcache, regnum,
+ ((const gdb_byte *)regs) + tdep->sizeof_gregset);
}
static const struct regset *
&& sect_size >= tdep->sizeof_gregset + I387_SIZEOF_FXSAVE)
{
if (tdep->gregset == NULL)
- {
- tdep->gregset = XMALLOC (struct regset);
- tdep->gregset->descr = tdep;
- tdep->gregset->supply_regset = amd64obsd_supply_regset;
- }
+ tdep->gregset = regset_alloc (gdbarch, amd64obsd_supply_regset, NULL);
return tdep->gregset;
}
/* Support for signal handlers. */
+/* Default page size. */
static const int amd64obsd_page_size = 4096;
+/* Return whether the frame preceding NEXT_FRAME corresponds to an
+ OpenBSD sigtramp routine. */
+
static int
-amd64obsd_pc_in_sigtramp (CORE_ADDR pc, char *name)
+amd64obsd_sigtramp_p (struct frame_info *next_frame)
{
+ CORE_ADDR pc = frame_pc_unwind (next_frame);
CORE_ADDR start_pc = (pc & ~(amd64obsd_page_size - 1));
- const char sigreturn[] =
+ const gdb_byte sigreturn[] =
{
0x48, 0xc7, 0xc0,
0x67, 0x00, 0x00, 0x00, /* movq $SYS_sigreturn, %rax */
0xcd, 0x80 /* int $0x80 */
};
- char *buf;
+ size_t buflen = (sizeof sigreturn) + 1;
+ gdb_byte *buf;
+ char *name;
+
+ /* If the function has a valid symbol name, it isn't a
+ trampoline. */
+ find_pc_partial_function (pc, &name, NULL, NULL);
+ if (name != NULL)
+ return 0;
- if (name)
+ /* If the function lives in a valid section (even without a starting
+ point) it isn't a trampoline. */
+ if (find_pc_section (pc) != NULL)
return 0;
/* If we can't read the instructions at START_PC, return zero. */
- buf = alloca (sizeof sigreturn);
- if (target_read_memory (start_pc + 0x7, buf, sizeof sigreturn))
+ buf = alloca ((sizeof sigreturn) + 1);
+ if (!safe_frame_unwind_memory (next_frame, start_pc + 6, buf, buflen))
return 0;
- /* Check for sigreturn(2). */
- if (memcmp (buf, sigreturn, sizeof sigreturn))
+ /* Check for sigreturn(2). Depending on how the assembler encoded
+ the `movq %rsp, %rdi' instruction, the code starts at offset 6 or
+ 7. */
+ if (memcmp (buf, sigreturn, sizeof sigreturn)
+ && memcpy (buf + 1, sigreturn, sizeof sigreturn))
return 0;
return 1;
static CORE_ADDR
amd64obsd_sigcontext_addr (struct frame_info *next_frame)
{
+ CORE_ADDR pc = frame_pc_unwind (next_frame);
+ ULONGEST offset = (pc & (amd64obsd_page_size - 1));
+
/* The %rsp register points at `struct sigcontext' upon entry of a
- signal trampoline. */
- return frame_unwind_register_unsigned (next_frame, AMD64_RSP_REGNUM);
+ signal trampoline. The relevant part of the trampoline is
+
+ call *%rax
+ movq %rsp, %rdi
+ pushq %rdi
+ movq $SYS_sigreturn,%rax
+ int $0x80
+
+ (see /usr/src/sys/arch/amd64/amd64/locore.S). The `pushq'
+ instruction clobbers %rsp, but its value is saved in `%rdi'. */
+
+ if (offset > 5)
+ return frame_unwind_register_unsigned (next_frame, AMD64_RDI_REGNUM);
+ else
+ return frame_unwind_register_unsigned (next_frame, AMD64_RSP_REGNUM);
}
\f
/* OpenBSD 3.5 or later. */
15 * 8 /* %gs */
};
+/* From /usr/src/lib/libpthread/arch/amd64/uthread_machdep.c. */
+static int amd64obsd_uthread_reg_offset[] =
+{
+ 19 * 8, /* %rax */
+ 16 * 8, /* %rbx */
+ 18 * 8, /* %rcx */
+ 17 * 8, /* %rdx */
+ 14 * 8, /* %rsi */
+ 13 * 8, /* %rdi */
+ 15 * 8, /* %rbp */
+ -1, /* %rsp */
+ 12 * 8, /* %r8 ... */
+ 11 * 8,
+ 10 * 8,
+ 9 * 8,
+ 8 * 8,
+ 7 * 8,
+ 6 * 8,
+ 5 * 8, /* ... %r15 */
+ 20 * 8, /* %rip */
+ 4 * 8, /* %eflags */
+ 21 * 8, /* %cs */
+ -1, /* %ss */
+ 3 * 8, /* %ds */
+ 2 * 8, /* %es */
+ 1 * 8, /* %fs */
+ 0 * 8 /* %gs */
+};
+
+/* Offset within the thread structure where we can find the saved
+ stack pointer (%esp). */
+#define AMD64OBSD_UTHREAD_RSP_OFFSET 400
+
+static void
+amd64obsd_supply_uthread (struct regcache *regcache,
+ int regnum, CORE_ADDR addr)
+{
+ CORE_ADDR sp_addr = addr + AMD64OBSD_UTHREAD_RSP_OFFSET;
+ CORE_ADDR sp = 0;
+ gdb_byte buf[8];
+ int i;
+
+ gdb_assert (regnum >= -1);
+
+ if (regnum == -1 || regnum == AMD64_RSP_REGNUM)
+ {
+ int offset;
+
+ /* Fetch stack pointer from thread structure. */
+ sp = read_memory_unsigned_integer (sp_addr, 8);
+
+ /* Adjust the stack pointer such that it looks as if we just
+ returned from _thread_machdep_switch. */
+ offset = amd64obsd_uthread_reg_offset[AMD64_RIP_REGNUM] + 8;
+ store_unsigned_integer (buf, 8, sp + offset);
+ regcache_raw_supply (regcache, AMD64_RSP_REGNUM, buf);
+ }
+
+ for (i = 0; i < ARRAY_SIZE (amd64obsd_uthread_reg_offset); i++)
+ {
+ if (amd64obsd_uthread_reg_offset[i] != -1
+ && (regnum == -1 || regnum == i))
+ {
+ /* Fetch stack pointer from thread structure (if we didn't
+ do so already). */
+ if (sp == 0)
+ sp = read_memory_unsigned_integer (sp_addr, 8);
+
+ /* Read the saved register from the stack frame. */
+ read_memory (sp + amd64obsd_uthread_reg_offset[i], buf, 8);
+ regcache_raw_supply (regcache, i, buf);
+ }
+ }
+}
+
+static void
+amd64obsd_collect_uthread (const struct regcache *regcache,
+ int regnum, CORE_ADDR addr)
+{
+ CORE_ADDR sp_addr = addr + AMD64OBSD_UTHREAD_RSP_OFFSET;
+ CORE_ADDR sp = 0;
+ gdb_byte buf[8];
+ int i;
+
+ gdb_assert (regnum >= -1);
+
+ if (regnum == -1 || regnum == AMD64_RSP_REGNUM)
+ {
+ int offset;
+
+ /* Calculate the stack pointer (frame pointer) that will be
+ stored into the thread structure. */
+ offset = amd64obsd_uthread_reg_offset[AMD64_RIP_REGNUM] + 8;
+ regcache_raw_collect (regcache, AMD64_RSP_REGNUM, buf);
+ sp = extract_unsigned_integer (buf, 8) - offset;
+
+ /* Store the stack pointer. */
+ write_memory_unsigned_integer (sp_addr, 8, sp);
+
+ /* The stack pointer was (potentially) modified. Make sure we
+ build a proper stack frame. */
+ regnum = -1;
+ }
+
+ for (i = 0; i < ARRAY_SIZE (amd64obsd_uthread_reg_offset); i++)
+ {
+ if (amd64obsd_uthread_reg_offset[i] != -1
+ && (regnum == -1 || regnum == i))
+ {
+ /* Fetch stack pointer from thread structure (if we didn't
+ calculate it already). */
+ if (sp == 0)
+ sp = read_memory_unsigned_integer (sp_addr, 8);
+
+ /* Write the register into the stack frame. */
+ regcache_raw_collect (regcache, i, buf);
+ write_memory (sp + amd64obsd_uthread_reg_offset[i], buf, 8);
+ }
+ }
+}
+/* Kernel debugging support. */
+
+/* From <machine/frame.h>. Easy since `struct trapframe' matches
+ `struct sigcontext'. */
+#define amd64obsd_tf_reg_offset amd64obsd_sc_reg_offset
+
+static struct trad_frame_cache *
+amd64obsd_trapframe_cache(struct frame_info *next_frame, void **this_cache)
+{
+ struct trad_frame_cache *cache;
+ CORE_ADDR func, sp, addr;
+ ULONGEST cs;
+ char *name;
+ int i;
+
+ if (*this_cache)
+ return *this_cache;
+
+ cache = trad_frame_cache_zalloc (next_frame);
+ *this_cache = cache;
+
+ /* NORMAL_FRAME matches the type in amd64obsd_trapframe_unwind, but
+ SIGTRAMP_FRAME might be more appropriate. */
+ func = frame_func_unwind (next_frame, NORMAL_FRAME);
+ sp = frame_unwind_register_unsigned (next_frame, AMD64_RSP_REGNUM);
+
+ find_pc_partial_function (func, &name, NULL, NULL);
+ if (name && strncmp (name, "Xintr", 5) == 0)
+ addr = sp + 8; /* It's an interrupt frame. */
+ else
+ addr = sp;
+
+ for (i = 0; i < ARRAY_SIZE (amd64obsd_tf_reg_offset); i++)
+ if (amd64obsd_tf_reg_offset[i] != -1)
+ trad_frame_set_reg_addr (cache, i, addr + amd64obsd_tf_reg_offset[i]);
+
+ /* Read %cs from trap frame. */
+ addr += amd64obsd_tf_reg_offset[AMD64_CS_REGNUM];
+ cs = read_memory_unsigned_integer (addr, 8);
+ if ((cs & I386_SEL_RPL) == I386_SEL_UPL)
+ {
+ /* Trap from user space; terminate backtrace. */
+ trad_frame_set_id (cache, null_frame_id);
+ }
+ else
+ {
+ /* Construct the frame ID using the function start. */
+ trad_frame_set_id (cache, frame_id_build (sp + 16, func));
+ }
+
+ return cache;
+}
+
+static void
+amd64obsd_trapframe_this_id (struct frame_info *next_frame,
+ void **this_cache, struct frame_id *this_id)
+{
+ struct trad_frame_cache *cache =
+ amd64obsd_trapframe_cache (next_frame, this_cache);
+
+ trad_frame_get_id (cache, this_id);
+}
+
+static void
+amd64obsd_trapframe_prev_register (struct frame_info *next_frame,
+ void **this_cache, int regnum,
+ int *optimizedp, enum lval_type *lvalp,
+ CORE_ADDR *addrp, int *realnump,
+ gdb_byte *valuep)
+{
+ struct trad_frame_cache *cache =
+ amd64obsd_trapframe_cache (next_frame, this_cache);
+
+ trad_frame_get_register (cache, next_frame, regnum,
+ optimizedp, lvalp, addrp, realnump, valuep);
+}
+
+static int
+amd64obsd_trapframe_sniffer (const struct frame_unwind *self,
+ struct frame_info *next_frame,
+ void **this_prologue_cache)
+{
+ ULONGEST cs;
+ char *name;
+
+ /* Check Current Privilege Level and bail out if we're not executing
+ in kernel space. */
+ cs = frame_unwind_register_unsigned (next_frame, AMD64_CS_REGNUM);
+ if ((cs & I386_SEL_RPL) == I386_SEL_UPL)
+ return 0;
+
+ find_pc_partial_function (frame_pc_unwind (next_frame), &name, NULL, NULL);
+ return (name && ((strcmp (name, "calltrap") == 0)
+ || (strcmp (name, "osyscall1") == 0)
+ || (strcmp (name, "Xsyscall") == 0)
+ || (strncmp (name, "Xintr", 5) == 0)));
+}
+
+static const struct frame_unwind amd64obsd_trapframe_unwind = {
+ /* FIXME: kettenis/20051219: This really is more like an interrupt
+ frame, but SIGTRAMP_FRAME would print <signal handler called>,
+ which really is not what we want here. */
+ NORMAL_FRAME,
+ amd64obsd_trapframe_this_id,
+ amd64obsd_trapframe_prev_register,
+ NULL,
+ amd64obsd_trapframe_sniffer
+};
+\f
+
static void
amd64obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
tdep->jb_pc_offset = 7 * 8;
- set_gdbarch_pc_in_sigtramp (gdbarch, amd64obsd_pc_in_sigtramp);
+ tdep->sigtramp_p = amd64obsd_sigtramp_p;
tdep->sigcontext_addr = amd64obsd_sigcontext_addr;
tdep->sc_reg_offset = amd64obsd_sc_reg_offset;
tdep->sc_num_regs = ARRAY_SIZE (amd64obsd_sc_reg_offset);
+ /* OpenBSD provides a user-level threads implementation. */
+ bsd_uthread_set_supply_uthread (gdbarch, amd64obsd_supply_uthread);
+ bsd_uthread_set_collect_uthread (gdbarch, amd64obsd_collect_uthread);
+
/* OpenBSD uses SVR4-style shared libraries. */
set_solib_svr4_fetch_link_map_offsets
(gdbarch, svr4_lp64_fetch_link_map_offsets);
+
+ /* Unwind kernel trap frames correctly. */
+ frame_unwind_prepend_unwinder (gdbarch, &amd64obsd_trapframe_unwind);
}
\f
projects / deliverable / binutils-gdb.git / blobdiff