+/* 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 (struct trad_frame_cache *) *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 && startswith (name, "Xintr"))
+ 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)
+ || (startswith (name, "Xintr"))));
+}
+
+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