Make branch extraction more intelligent

package/version

@@ -1 +1 @@
-0.1.439
+0.1.440

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "poetry.core.masonry.api"
 
 [tool.poetry]
 name = "pyk"
-version = "0.1.439"
+version = "0.1.440"
 description = ""
 authors = [
     "Runtime Verification, Inc. <[email protected]>",

src/pyk/kcfg/explore.py

@@ -377,14 +377,24 @@ def extend(
         if self._check_abstract(node, kcfg):
             return
 
-        if not kcfg.splits(target_id=node.id):
-            branches = self.kcfg_semantics.extract_branches(node.cterm)
-            if branches:
-                kcfg.split_on_constraints(node.id, branches)
-                _LOGGER.info(
-                    f'Found {len(branches)} branches using heuristic for node {node.id}: {shorten_hashes(node.id)}: {[self.kprint.pretty_print(bc) for bc in branches]}'
-                )
-                return
+        branches = self.kcfg_semantics.extract_branches(node.cterm)
+
+        branch_conditions = []
+        branch_cterms = []
+
+        for constraint in branches:
+            cterm = node.cterm.add_constraint(constraint)
+            cterm, _ = self.cterm_simplify(cterm)
+            if not cterm.is_bottom:
+                branch_conditions.append(constraint)
+                branch_cterms.append(cterm)
+
+        if len(branch_cterms) > 1 and branches:
+            kcfg.branch(node.id, zip(branch_cterms, branch_conditions, strict=True))
+            _LOGGER.info(
+                f'Found {len(branches)} branches using heuristic for node {node.id}: {shorten_hashes(node.id)}: {[self.kprint.pretty_print(bc) for bc in branches]}'
+            )
+            return
 
         _LOGGER.info(f'Extending KCFG from node {self.id}: {shorten_hashes(node.id)}')
         _is_vacuous, depth, cterm, next_cterms, next_node_logs = self.cterm_execute(
@@ -437,7 +447,9 @@ def extend(
 
             # Split on branch patterns
             if any(branch_pattern.match(branch_and) for branch_pattern in branch_patterns):
-                kcfg.split_on_constraints(node.id, branches)
+                branch_cterms = [node.cterm.add_constraint(branch) for branch in branches]
+
+                kcfg.branch(node.id, zip(branch_cterms, branches, strict=True))
                 _LOGGER.info(
                     f'Found {len(branches)} branches for node {self.id}: {shorten_hashes(node.id)}: {[self.kprint.pretty_print(bc) for bc in branches]}'
                 )

src/pyk/kcfg/kcfg.py

@@ -724,10 +724,13 @@ def create_ndbranch(self, source_id: NodeIdLike, ndbranches: Iterable[NodeIdLike
         ndbranch = KCFG.NDBranch(self.node(source_id), tuple(self.node(nid) for nid in ndbranches))
         self._ndbranches[source_id] = ndbranch
 
-    def split_on_constraints(self, source_id: NodeIdLike, constraints: Iterable[KInner]) -> list[int]:
+    def branch(self, source_id: NodeIdLike, splits: Iterable[tuple[CTerm, KInner]]) -> list[int]:
         source = self.node(source_id)
-        branch_node_ids = [self.create_node(source.cterm.add_constraint(c)).id for c in constraints]
-        csubsts = [CSubst(constraints=flatten_label('#And', constraint)) for constraint in constraints]
+        branch_node_ids = []
+        csubsts = []
+        for cterm, constraint in splits:
+            branch_node_ids.append(self.create_node(cterm).id)
+            csubsts.append(CSubst(constraints=flatten_label('#And', constraint)))
         self.create_split(source.id, zip(branch_node_ids, csubsts, strict=True))
         return branch_node_ids