Convert infcalls to thread_fsm mechanism

This removes infcall-specific special casing from normal_stop,
simplifying it.

Like the "finish" command's, the FSM is responsible for storing the
function's return value.

gdb/ChangeLog:
2015-09-09  Pedro Alves  <palves@redhat.com>

	* infcall.c: Include thread_fsm.h.
	(struct call_return_meta_info): New.
	(get_call_return_value): New function, factored out from
	call_function_by_hand_dummy.
	(struct call_thread_fsm): New.
	(call_thread_fsm_ops): New global.
	(new_call_thread_fsm, call_thread_fsm_should_stop)
	(call_thread_fsm_should_notify_stop): New functions.
	(run_inferior_call): Add 'sm' parameter.  Associate the FSM with
	the thread.
	(call_function_by_hand_dummy): Create a new call_thread_fsm
	instance, associate it with the thread, and wait for the FSM to
	finish.  If finished successfully, fetch the function's result
	value out of the FSM.
	* infrun.c (fetch_inferior_event): If the FSM says the stop
	shouldn't be notified, don't call normal_stop.
	(maybe_remove_breakpoints): New function, factored out from ...
	(normal_stop): ... here.  Simplify.
	* infrun.h (maybe_remove_breakpoints): Declare.
	* thread-fsm.c (thread_fsm_should_notify_stop): New function.
	(thread-fsm.h) <struct thread_fsm_ops>: New field.
	(thread_fsm_should_notify_stop): Declare.

1 files changed, 10 insertions, 0 deletions

diff --git a/gdb/thread-fsm.c b/gdb/thread-fsm.c
index 761ad1c..4a27d02 100644
--- a/gdb/thread-fsm.c
+++ b/gdb/thread-fsm.c
@@ -95,3 +95,13 @@ thread_fsm_async_reply_reason (struct thread_fsm *self)
 
   return self->ops->async_reply_reason (self);
 }
+
+/* See thread-fsm.h.  */
+
+int
+thread_fsm_should_notify_stop (struct thread_fsm *self)
+{
+  if (self->ops->should_notify_stop != NULL)
+    return self->ops->should_notify_stop (self);
+  return 1;
+}