Implemented additional "arena" hierarchical priority semantics + corrected existing semantics (Source-Child semantics does no longer reverse "explicit" (document) order of transitions of equal priority). Add tests for hierarchical priority semantics.

src/sccd/statechart/dynamic/round.py

@@ -20,7 +20,12 @@ if timer.TIMINGS:
         print("\ncache hits: %s, cache misses: %s" %(ctr.cache_hits, ctr.cache_misses))
     atexit.register(print_stats)
 
+
 class GeneratorStrategy(ABC):
+    __slots__ = ["priority_ordered_transitions"]
+    def __init__(self, priority_ordered_transitions):
+        self.priority_ordered_transitions = priority_ordered_transitions
+
     @abstractmethod
     def cache_init(self):
         pass
@@ -30,7 +35,7 @@ class GeneratorStrategy(ABC):
         pass
 
     @abstractmethod
-    def generate(self, execution, enabled_events, events_bitmap, forbidden_arenas):
+    def generate(self, execution, events_bitmap, forbidden_arenas):
         pass
 
     @abstractmethod
@@ -38,10 +43,8 @@ class GeneratorStrategy(ABC):
         pass
 
 
+# First filter on current state, then filter on current events
 class CurrentConfigStrategy(GeneratorStrategy):
-    __slots__ = ["statechart"]
-    def __init__(self, statechart):
-        self.statechart = statechart
 
     def cache_init(self):
         return {}
@@ -49,36 +52,60 @@ class CurrentConfigStrategy(GeneratorStrategy):
     def key(self, execution, events_bitmap, forbidden_arenas):
         return (execution.configuration, forbidden_arenas)
 
-    def generate(self, execution, enabled_events, events_bitmap, forbidden_arenas):
-        return [ t for state_id in bm_items(execution.configuration)
-                      for t in self.statechart.tree.state_list[state_id].transitions
-                       if (not forbidden_arenas & t.opt.arena_bitmap) ]
+    def generate(self, execution, events_bitmap, forbidden_arenas):
+        return [ t for t in self.priority_ordered_transitions
+                      if (t.source.opt.state_id_bitmap & execution.configuration)
+                       and (not forbidden_arenas & t.opt.arena_bitmap) ]
 
     def filter_f(self, execution, enabled_events, events_bitmap):
         return lambda t: (not t.trigger or t.trigger.check(events_bitmap)) and execution.check_guard(t, enabled_events)
 
+# First filter based on current events, then filter on current state
 class EnabledEventsStrategy(GeneratorStrategy):
     __slots__ = ["statechart"]
-    def __init__(self, statechart):
+    def __init__(self, priority_ordered_transitions, statechart):
+        super().__init__(priority_ordered_transitions)
         self.statechart = statechart
 
     def cache_init(self):
         cache = {}
         for event_id in bm_items(self.statechart.events):
             events_bitmap = bit(event_id)
-            cache[(events_bitmap, 0)] = self.generate(None, None, events_bitmap, 0)
+            cache[(events_bitmap, 0)] = self.generate(None, events_bitmap, 0)
         return cache
 
     def key(self, execution, events_bitmap, forbidden_arenas):
         return (events_bitmap, forbidden_arenas)
 
-    def generate(self, execution, enabled_events, events_bitmap, forbidden_arenas):
-        return [ t for t in self.statechart.tree.transition_list
+    def generate(self, execution, events_bitmap, forbidden_arenas):
+        return [ t for t in self.priority_ordered_transitions
+                      if (not t.trigger or t.trigger.check(events_bitmap))
+                      and (not forbidden_arenas & t.opt.arena_bitmap) ]
+
+    def filter_f(self, execution, enabled_events, events_bitmap):
+        return lambda t: (execution.configuration & t.source.opt.state_id_bitmap) and execution.check_guard(t, enabled_events)
+
+class CurrentConfigAndEnabledEventsStrategy(GeneratorStrategy):
+    __slots__ = ["statechart"]
+    def __init__(self, priority_ordered_transitions, statechart):
+        super().__init__(priority_ordered_transitions)
+        self.statechart = statechart
+
+    def cache_init(self):
+        return {}
+
+    def key(self, execution, events_bitmap, forbidden_arenas):
+        return (execution.configuration, events_bitmap, forbidden_arenas)
+
+    def generate(self, execution, events_bitmap, forbidden_arenas):
+        return [ t for t in self.priority_ordered_transitions
                       if (not t.trigger or t.trigger.check(events_bitmap))
+                      and (t.source.opt.state_id_bitmap & execution.configuration)
                       and (not forbidden_arenas & t.opt.arena_bitmap) ]
 
     def filter_f(self, execution, enabled_events, events_bitmap):
-        return lambda t: execution.check_source(t) and execution.check_guard(t, enabled_events)
+        return lambda t: execution.check_guard(t, enabled_events)
+
 
 class CandidateGenerator:
     __slots__ = ["strategy", "cache"]
@@ -94,7 +121,7 @@ class CandidateGenerator:
             candidates = self.cache[key]
             ctr.cache_hits += 1
         except KeyError:
-            candidates = self.cache[key] = self.strategy.generate(execution, enabled_events, events_bitmap, forbidden_arenas)
+            candidates = self.cache[key] = self.strategy.generate(execution, events_bitmap, forbidden_arenas)
             ctr.cache_misses += 1
 
         return filter(self.strategy.filter_f(execution, enabled_events, events_bitmap), candidates)

src/sccd/statechart/dynamic/statechart_execution.py

@@ -121,9 +121,6 @@ class StatechartExecution:
             e.args = ("While checking guard of transition %s:\n" % str(t) +str(e),)
             raise
 
-    def check_source(self, t) -> bool:
-        return self.configuration & t.source.opt.state_id_bitmap
-
     @staticmethod
     def _perform_actions(ctx: EvalContext, actions: List[Action]):
         for a in actions:

src/sccd/statechart/dynamic/statechart_instance.py

@@ -35,13 +35,20 @@ class StatechartInstance(Instance):
         if semantics.has_multiple_variants():
             raise Exception("Cannot execute model with multiple semantics.")
 
-        reverse = semantics.priority == Priority.SOURCE_CHILD
+        priority_function = {
+            Priority.SOURCE_PARENT: priority_source_parent,
+            Priority.SOURCE_CHILD: priority_source_child,
+            Priority.ARENA_PARENT: priority_arena_parent,
+            Priority.ARENA_CHILD: priority_arena_child,
+        }[semantics.priority]
 
-        # 2 transition candidate generation algorithms to choose from!
-        # generator = CandidatesGeneratorCurrentConfigBased(statechart, reverse)
-        # generator = CandidatesGeneratorEventBased(statechart, reverse)
-        # generator = CandidateGenerator(CurrentConfigStrategy(statechart))
-        generator = CandidateGenerator(EnabledEventsStrategy(statechart))
+        priority_ordered_transitions = priority_function(statechart.tree)
+
+        # strategy = CurrentConfigStrategy(priority_ordered_transitions)
+        strategy = EnabledEventsStrategy(priority_ordered_transitions, statechart)
+        # strategy = CurrentConfigAndEnabledEventsStrategy(priority_ordered_transitions, statechart)
+
+        generator = CandidateGenerator(strategy)
 
         # Big step + combo step maximality semantics
 

src/sccd/statechart/static/tree.py

@@ -1,5 +1,6 @@
 import termcolor
 from typing import *
+import itertools
 from sccd.statechart.static.action import *
 from sccd.util.bitmap import *
 from sccd.util import timer
@@ -27,7 +28,6 @@ class State(Freezable):
 
         self.opt: Optional['StateOptimization'] = None
 
-    # def __post_init__(self):
         if self.parent is not None:
             self.parent.children.append(self)
 
@@ -189,12 +189,13 @@ class Transition(Freezable):
 
 # Data that is generated for each state.
 class StateOptimization(Freezable):
-    __slots__ = ["full_name", "state_id", "state_id_bitmap", "ancestors", "descendants", "history", "ts_static", "ts_dynamic", "after_triggers"]
+    __slots__ = ["full_name", "depth", "state_id", "state_id_bitmap", "ancestors", "descendants", "history", "ts_static", "ts_dynamic", "after_triggers"]
     def __init__(self):
         super().__init__()
 
         self.full_name: str = ""
 
+        self.depth: int -1 # Root is 0, root's children are 1, and so on
         self.state_id: int = -1
         self.state_id_bitmap: Bitmap = Bitmap() # bitmap with only state_id-bit set
 
@@ -273,6 +274,10 @@ def optimize_tree(root: State) -> StateTree:
 
             return f
 
+        def assign_depth(state: State, parent_depth: int = 0):
+            state.opt.depth = parent_depth + 1
+            return parent_depth + 1
+
         def assign_full_name(state: State, parent_full_name: str = ""):
             if state is root:
                 full_name = '/'
@@ -330,6 +335,7 @@ def optimize_tree(root: State) -> StateTree:
             before_children=[
                 init_opt(),
                 assign_full_name,
+                assign_depth,
                 add_to_list,
                 set_ancestors,
             ],
@@ -342,7 +348,7 @@ def optimize_tree(root: State) -> StateTree:
 
 
         for t in transition_list:
-            # Arena can be computed statically. First computer Lowest-common ancestor:
+            # Arena can be computed statically. First compute Lowest-common ancestor:
             # Intersection between source & target ancestors, last member in depth-first sorted state list.
             lca_id = bm_highest_bit(t.source.opt.ancestors & t.targets[0].opt.ancestors)
             lca = state_list[lca_id]
@@ -389,3 +395,54 @@ def optimize_tree(root: State) -> StateTree:
             t.freeze()
 
         return StateTree(root, transition_list, state_list, state_dict, after_triggers, stable_bitmap, history_states)
+
+
+def priority_source_parent(tree: StateTree) -> List[Transition]:
+    # Tree's transition list already ordered parent-first
+    return tree.transition_list
+
+def priority_source_child(tree: StateTree) -> List[Transition]:
+    # Build a child-first order of transitions, while maintaining document order between transitions at the same level
+    transition_list = []
+    def append(state: State, _=None):
+        transition_list.extend(state.transitions)
+    visit_tree(tree.root, lambda s: s.children, before_children=[], after_children=[append])
+    return transition_list
+
+def priority_arena_parent(tree: StateTree) -> List[Transition]:
+    # partial ordering key + Python's stable sorting = desired outcome
+    return list(sorted(tree.transition_list, key=lambda t: t.opt.arena.opt.depth))
+
+def priority_arena_child(tree: StateTree) -> List[Transition]:
+    return list(sorted(tree.transition_list, key=lambda t: -t.opt.arena.opt.depth))
+
+
+def concurrency_arena_orthogonal(tree: StateTree):
+    with timer.Context("concurrency_arena_orthogonal"):
+        import collections
+        nonoverlapping = collections.defaultdict(list)
+        for t1,t2 in itertools.combinations(tree.transition_list, r=2):
+            if not (t1.opt.arena_bitmap & t2.opt.arena_bitmap):
+                nonoverlapping[t1].append(t2)
+                nonoverlapping[t2].append(t1)
+
+        for t, ts in nonoverlapping.items():
+            print(str(t), "does not overlap with", ",".join(str(t) for t in ts))
+
+        print(len(nonoverlapping), "nonoverlapping pairs of transitions")
+
+def concurrency_src_dst_orthogonal(tree: StateTree):
+    with timer.Context("concurrency_src_dst_orthogonal"):
+        import collections
+        nonoverlapping = collections.defaultdict(list)
+        for t1,t2 in itertools.combinations(tree.transition_list, r=2):
+            lca_src = tree.state_list[bm_highest_bit(t1.source.opt.ancestors & t2.source.opt.ancestors)]
+            lca_dst = tree.state_list[bm_highest_bit(t1.targets[0].opt.ancestors & t2.targets[0].opt.ancestors)]
+            if isinstance(lca_src, ParallelState) and isinstance(lca_dst, ParallelState):
+                nonoverlapping[t1].append(t2)
+                nonoverlapping[t2].append(t1)
+
+        for t, ts in nonoverlapping.items():
+            print(str(t), "does not overlap with", ",".join(str(t) for t in ts))
+
+        print(len(nonoverlapping), "nonoverlapping pairs of transitions")

test/test_files/semantics/priority/statechart_priority_hierarchical.svg

@@ -0,0 +1,135 @@
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+<path fill="none" stroke="#000000" d="M170.2855,-219.8368C171.1448,-201.4912 171.2972,-172.4466 166,-148 159.9258,-119.9676 146.77,-89.9441 136.4175,-69.0327"/>
+<polygon fill="#000000" stroke="#000000" points="139.5361,-67.4437 131.8938,-60.1058 133.2921,-70.608 139.5361,-67.4437"/>
+<text text-anchor="start" x="161" y="-110" font-family="Helvetica,sans-Serif" font-size="10.00" fill="#000000">^out.arena_child &#160;&#160;</text>
+</g>
+</g>
+</svg>

test/test_files/semantics/priority/statechart_priority_hierarchical.xml

@@ -0,0 +1,42 @@
+<?xml version="1.0" ?>
+<statechart>
+
+  <inport name="in">
+    <event name="start"/>
+  </inport>
+
+  <outport name="out">
+    <event name="source_parent"/>
+    <event name="source_child"/>
+    <event name="arena_parent"/>
+    <event name="arena_child"/>
+  </outport>
+
+  <root initial="s1">
+    <state id="s1" initial="s2">
+      <state id="s2" initial="s3">
+        <state id="s3">
+          <transition target="/s1/s5">
+            <!-- with source-child, this transition is preferred above the other
+                 outgoing ones, because this one occurs first in the document -->
+            <raise event="source_child"/>
+          </transition>
+          <transition target="../s4">
+            <raise event="arena_child"/>
+          </transition>
+          <transition target="/s6/s7">
+            <raise event="arena_parent"/>
+          </transition>
+        </state>
+        <state id="s4"/>
+        <transition target="../s5">
+          <raise event="source_parent"/>
+        </transition>
+      </state>
+      <state id="s5"/>
+    </state>
+    <state id="s6">
+      <state id="s7"/>
+    </state>
+  </root>
+</statechart>

test/test_files/semantics/priority/test_arena_child.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" ?>
+<test>
+  <statechart src="statechart_priority_hierarchical.xml">
+    <override_semantics
+      big_step_maximality="take_one"
+      priority="arena_child"/>
+  </statechart>
+  <input>
+      <event name="start" port="in" time="0 d"/>
+  </input>
+  <output>
+    <big_step>
+      <event name="arena_child" port="out"/>
+    </big_step>
+  </output>
+</test>

test/test_files/semantics/priority/test_arena_parent.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" ?>
+<test>
+  <statechart src="statechart_priority_hierarchical.xml">
+    <override_semantics
+      big_step_maximality="take_one"
+      priority="arena_parent"/>
+  </statechart>
+  <input>
+      <event name="start" port="in" time="0 d"/>
+  </input>
+  <output>
+    <big_step>
+      <event name="arena_parent" port="out"/>
+    </big_step>
+  </output>
+</test>

test/test_files/semantics/priority/test_source_child.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" ?>
+<test>
+  <statechart src="statechart_priority_hierarchical.xml">
+    <override_semantics
+      big_step_maximality="take_one"
+      priority="source_child"/>
+  </statechart>
+  <input>
+      <event name="start" port="in" time="0 d"/>
+  </input>
+  <output>
+    <big_step>
+      <event name="source_child" port="out"/>
+    </big_step>
+  </output>
+</test>

test/test_files/semantics/priority/test_source_parent.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" ?>
+<test>
+  <statechart src="statechart_priority_hierarchical.xml">
+    <override_semantics
+      big_step_maximality="take_one"
+      priority="source_parent"/>
+  </statechart>
+  <input>
+      <event name="start" port="in" time="0 d"/>
+  </input>
+  <output>
+    <big_step>
+      <event name="source_parent" port="out"/>
+    </big_step>
+  </output>
+</test>