+/* 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)
+{
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ 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, byte_order);
+
+ /* 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, byte_order, 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, byte_order);
+
+ /* 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)
+{
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ 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, byte_order) - offset;
+
+ /* Store the stack pointer. */
+ write_memory_unsigned_integer (sp_addr, 8, byte_order, 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, byte_order);
+
+ /* 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 *this_frame, void **this_cache)
+{
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ struct trad_frame_cache *cache;
+ CORE_ADDR func, sp, addr;
+ ULONGEST cs;
+ const char *name;
+ int i;
+
+ if (*this_cache)
+ return *this_cache;
+
+ cache = trad_frame_cache_zalloc (this_frame);
+ *this_cache = cache;
+
+ func = get_frame_func (this_frame);
+ sp = get_frame_register_unsigned (this_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, byte_order);
+ if ((cs & I386_SEL_RPL) == I386_SEL_UPL)
+ {
+ /* Trap from user space; terminate backtrace. */
+ trad_frame_set_id (cache, outer_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 *this_frame,
+ void **this_cache, struct frame_id *this_id)
+{
+ struct trad_frame_cache *cache =
+ amd64obsd_trapframe_cache (this_frame, this_cache);
+
+ trad_frame_get_id (cache, this_id);
+}
+
+static struct value *
+amd64obsd_trapframe_prev_register (struct frame_info *this_frame,
+ void **this_cache, int regnum)
+{
+ struct trad_frame_cache *cache =
+ amd64obsd_trapframe_cache (this_frame, this_cache);
+
+ return trad_frame_get_register (cache, this_frame, regnum);
+}
+
+static int
+amd64obsd_trapframe_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame,
+ void **this_prologue_cache)
+{
+ ULONGEST cs;
+ const char *name;
+
+ /* Check Current Privilege Level and bail out if we're not executing
+ in kernel space. */
+ cs = get_frame_register_unsigned (this_frame, AMD64_CS_REGNUM);
+ if ((cs & I386_SEL_RPL) == I386_SEL_UPL)
+ return 0;
+
+ find_pc_partial_function (get_frame_pc (this_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,
+ default_frame_unwind_stop_reason,
+ amd64obsd_trapframe_this_id,
+ amd64obsd_trapframe_prev_register,
+ NULL,
+ amd64obsd_trapframe_sniffer
+};
+\f
+