Prune #Bottom states when branching (#3650)

Fix for change introduced by #3637, wherein branching could contain
bottom states which were not being pruned. (see
runtimeverification/pyk#634 (comment))

Author: goodlyrottenapple

cabal.project.freeze

@@ -11,7 +11,6 @@ constraints: any.Cabal ==3.6.3.0,
              aeson -cffi +ordered-keymap,
              any.aeson-pretty ==0.8.9,
              aeson-pretty -lib-only,
-             any.alex ==3.2.7.4,
              any.ansi-terminal ==0.11.4,
              ansi-terminal -example +win32-2-13-1,
              any.ansi-wl-pprint ==0.6.9,
@@ -109,7 +108,6 @@ constraints: any.Cabal ==3.6.3.0,
              any.gitrev ==1.3.1,
              any.graphviz ==2999.20.1.0,
              graphviz -test-parsing,
-             any.happy ==1.20.1.1,
              any.hashable ==1.4.2.0,
              hashable +integer-gmp -random-initial-seed,
              any.hashtables ==1.3.1,

kore/src/Kore/Exec.hs

@@ -557,8 +557,16 @@ rpcExec
                     Rewritten _ -> GraphTraversal.Continuing next'
                     Remaining _ -> GraphTraversal.Stuck next'
                     Kore.Rewrite.Bottom -> GraphTraversal.Vacuous prior
-        toTransitionResult prior (s : ss) =
-            GraphTraversal.Branch prior $ fmap fst (s :| ss)
+        toTransitionResult prior rs =
+            case filter
+                ( \(RpcExecState{rpcProgState}, _) -> case rpcProgState of
+                    Kore.Rewrite.Bottom -> False
+                    _ -> True
+                )
+                rs of
+                (s : ss) -> GraphTraversal.Branch prior $ fmap fst (s :| ss)
+                --  either empty or single result
+                other -> toTransitionResult prior other
 
         setTraces ::
             Seq (RewriteRule v, Seq SimplifierTrace) -> Seq RuleTrace -> RpcExecState v -> RpcExecState v