From 2c7466e2de76d3a651579994bdf933974a8bd92d Mon Sep 17 00:00:00 2001
From: Tom Barthe <tom.barthe@ens-paris-saclay.fr>
Date: Wed, 30 Dec 2020 02:03:06 +0100
Subject: [PATCH] Reset only stateful async nodes

---
 compiler/obc/c/async.ml          | 12 ++++++++++--
 compiler/obc/c/async_avr.ml      |  3 ++-
 compiler/obc/c/async_backend.mli |  1 +
 compiler/obc/c/cmain.ml          |  8 ++++++++
 4 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/compiler/obc/c/async.ml b/compiler/obc/c/async.ml
index 4004706..5e98090 100644
--- a/compiler/obc/c/async.ml
+++ b/compiler/obc/c/async.ml
@@ -1,7 +1,9 @@
 open Obc
 open C
+open Modules
 open Idents
 open Names
+open Signature
 
 let async_global_var_name od = "g_async__" ^ (name od.o_ident)
 
@@ -31,12 +33,18 @@ let async_global_objs_decls cd =
     (fun (name, ty) -> Cdecl_extern (name, ty))
     (async_global_objs_vars cd)
 
+let od_is_stateful od =
+  let sig_info = find_value od.o_class in
+  sig_info.node_stateful
+
 let async_reset cd =
+  let async_objs = filter_async_objs cd in
+  let stateful = List.filter od_is_stateful async_objs in
   List.map
     (fun od ->
        let global = Cvar (async_global_var_name od) in
-       let field = Cfield (global, local_qn "mem") in
+       let field = Cfield (global, local_qn "self") in
        let reset = cname_of_qn od.o_class ^ "_reset" in
        Csexpr (Cfun_call (reset, [Caddrof field])))
-  (filter_async_objs cd)
+  stateful
 
diff --git a/compiler/obc/c/async_avr.ml b/compiler/obc/c/async_avr.ml
index 8044e15..310d33f 100644
--- a/compiler/obc/c/async_avr.ml
+++ b/compiler/obc/c/async_avr.ml
@@ -11,7 +11,6 @@ struct
     | Timer_ms of int
 
   (* FIXME(Arduino): don't do a shallow copy *)
-  (* FIXME(Arduino): add a mutex… *)
   let gen_copy_func cd suffix =
     let func_name = (cname_of_qn cd.cd_name) ^ "_copy" ^ suffix in
     (* TODO(Arduino): add const qualifier *)
@@ -109,4 +108,6 @@ struct
     ] in
     [], defs
 
+  let main_init = [Csexpr (Cfun_call ("init_timer1", []))]
+
 end
diff --git a/compiler/obc/c/async_backend.mli b/compiler/obc/c/async_backend.mli
index 10d09f9..ed322b7 100644
--- a/compiler/obc/c/async_backend.mli
+++ b/compiler/obc/c/async_backend.mli
@@ -7,4 +7,5 @@ sig
   val gen_copy_func_out : class_def -> cdef
   val includes : string list
   val decls_and_defs : obj_dec list -> cdecl list * cdef list
+  val main_init : cstm list
 end
diff --git a/compiler/obc/c/cmain.ml b/compiler/obc/c/cmain.ml
index 1781270..7780abb 100644
--- a/compiler/obc/c/cmain.ml
+++ b/compiler/obc/c/cmain.ml
@@ -37,6 +37,7 @@ open Signature
 open C
 open Cgen
 open Async
+open Async_avr
 open Compiler_utils
 
 (** {1 Main C function generation} *)
@@ -412,6 +413,13 @@ let mk_main name p =
         classes
       in
 
+      (*
+       * We add these instructions at the end because otherwise the timer
+       * could be triggered while the initial reset of the async nodes is
+       * not yet terminated.
+       *)
+      let res_l = res_l @ AvrBackend.main_init in
+
       [("_main.c", Csource (defs @ [main_skel var_l res_l step_l]));
        ("_main.h", Cheader ([name], []))];
   ) else