From 8493ca2ad26d4f6b2aaab8b7600bda2e52b2b131 Mon Sep 17 00:00:00 2001
From: Omer Katz <omerk2511@gmail.com>
Date: Sun, 27 Mar 2022 20:24:16 +0300
Subject: [PATCH 1/2] Optimized the generic dominator calculation a bit by
 preventing redundant initial calculations

---
 miasm/core/graph.py | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/miasm/core/graph.py b/miasm/core/graph.py
index 0dfd7e6ac..c414225ec 100644
--- a/miasm/core/graph.py
+++ b/miasm/core/graph.py
@@ -416,15 +416,11 @@ def _compute_generic_dominators(head, reachable_cb, prev_cb, next_cb):
             dominators[node] = set(nodes)
 
         dominators[head] = set([head])
-        todo = set(nodes)
+        todo = set([succ for succ in next_cb(head)])
 
         while todo:
             node = todo.pop()
 
-            # Heads state must not be changed
-            if node == head:
-                continue
-
             # Compute intersection of all predecessors'dominators
             new_dom = None
             for pred in prev_cb(node):
@@ -446,6 +442,7 @@ def _compute_generic_dominators(head, reachable_cb, prev_cb, next_cb):
             dominators[node] = new_dom
             for succ in next_cb(node):
                 todo.add(succ)
+
         return dominators
 
     def compute_dominators(self, head):

From 9bc1a8f56d7742b17c973a6fffdcbf47ae3432fe Mon Sep 17 00:00:00 2001
From: Omer Katz <omerk2511@gmail.com>
Date: Sun, 27 Mar 2022 21:33:11 +0300
Subject: [PATCH 2/2] Bugfix - the assumption that the head node can never be a
 sucessor of any node in the graph is correct, but this is a *generic*
 function, so it should handle postdominators as well, whose head can be a
 predecessor of some node in the graph. Thus, the node == head check is still
 required.

---
 miasm/core/graph.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/miasm/core/graph.py b/miasm/core/graph.py
index c414225ec..0d7ce52f4 100644
--- a/miasm/core/graph.py
+++ b/miasm/core/graph.py
@@ -416,11 +416,15 @@ def _compute_generic_dominators(head, reachable_cb, prev_cb, next_cb):
             dominators[node] = set(nodes)
 
         dominators[head] = set([head])
-        todo = set([succ for succ in next_cb(head)])
+        todo = set([n for n in next_cb(head)])
 
         while todo:
             node = todo.pop()
 
+            # Head's state must not be changed
+            if node == head:
+                continue
+
             # Compute intersection of all predecessors'dominators
             new_dom = None
             for pred in prev_cb(node):