2013-07-24 Sergio Durigan Junior <sergiodj@redhat.com>

	* breakpoint.c (create_longjmp_master_breakpoint): Check if probe
	interface can evaluate arguments.  Fallback to the old mode if it
	cannot.
	(create_exception_master_breakpoint): Likewise.
	* elfread.c (elf_can_evaluate_probe_arguments): New function.
	(struct sym_probe_fns elf_probe_fns): Export function above to the
	probe interface.
	* probe.c (can_evaluate_probe_arguments): New function.
	* probe.h (struct probe_ops) <can_evaluate_probe_arguments>: New
	function pointer.
	(can_evaluate_probe_arguments): New function prototype.
	* solib-svr4.c (svr4_create_solib_event_breakpoints): Check if
	probe interface can evaluate arguments.  Fallback to the old mode
	if it cannot.
	* stap-probe.c (stap_get_probe_argument_count): Check if probe
	interface can evaluate arguments.  Warning the user if it cannot.
	(stap_can_evaluate_probe_arguments): New function.
	(struct probe_ops stap_probe_ops): Export function above to the
	probe interface.
	* symfile.h (struct sym_probe_fns) <can_evaluate_probe_arguments>:
	New function pointer.

1 files changed, 36 insertions, 1 deletions

diff --git a/gdb/stap-probe.c b/gdb/stap-probe.c
index 1079e3b..cbbdf391 100644
--- a/gdb/stap-probe.c
+++ b/gdb/stap-probe.c
@@ -1009,7 +1009,27 @@ stap_get_probe_argument_count (struct probe *probe_generic)
   gdb_assert (probe_generic->pops == &stap_probe_ops);
 
   if (!probe->args_parsed)
-    stap_parse_probe_arguments (probe);
+    {
+      if (probe_generic->pops->can_evaluate_probe_arguments (probe_generic))
+	stap_parse_probe_arguments (probe);
+      else
+	{
+	  static int have_warned_stap_incomplete = 0;
+
+	  if (!have_warned_stap_incomplete)
+	    {
+	      warning (_(
+"The SystemTap SDT probe support is not fully implemented on this target;\n"
+"you will not be able to inspect the arguments of the probes.\n"
+"Please report a bug against GDB requesting a port to this target."));
+	      have_warned_stap_incomplete = 1;
+	    }
+
+	  /* Marking the arguments as "already parsed".  */
+	  probe->args_u.vec = NULL;
+	  probe->args_parsed = 1;
+	}
+    }
 
   gdb_assert (probe->args_parsed);
   return VEC_length (stap_probe_arg_s, probe->args_u.vec);
@@ -1060,6 +1080,20 @@ stap_get_arg (struct stap_probe *probe, unsigned n)
   return VEC_index (stap_probe_arg_s, probe->args_u.vec, n);
 }
 
+/* Implement the `can_evaluate_probe_arguments' method of probe_ops.  */
+
+static int
+stap_can_evaluate_probe_arguments (struct probe *probe_generic)
+{
+  struct stap_probe *stap_probe = (struct stap_probe *) probe_generic;
+  struct gdbarch *gdbarch = stap_probe->p.objfile->gdbarch;
+
+  /* For SystemTap probes, we have to guarantee that the method
+     stap_is_single_operand is defined on gdbarch.  If it is not, then it
+     means that argument evaluation is not implemented on this target.  */
+  return gdbarch_stap_is_single_operand_p (gdbarch);
+}
+
 /* Evaluate the probe's argument N (indexed from 0), returning a value
    corresponding to it.  Assertion is thrown if N does not exist.  */
 
@@ -1520,6 +1554,7 @@ static const struct probe_ops stap_probe_ops =
   stap_get_probes,
   stap_relocate,
   stap_get_probe_argument_count,
+  stap_can_evaluate_probe_arguments,
   stap_evaluate_probe_argument,
   stap_compile_to_ax,
   stap_set_semaphore,