complement in 11.13

notes/9.md

@@ -0,0 +1,28 @@
+# Control Flow Analysis
+
+Dominator
+
+for a given CFG **a node `x` dominates a node `y`** if every path from the Entry block to `y` contains `x`.
+
+* Each BB dominates itself
+* If `x dom y` and `y dom z` then `x dom z`
+* If `x dom z` and `y dom z` then either `x dom y` or `y dom x`
+
+Dominator Tree
+* initial node is a root
+* `x dom y` means that "`y` is a child of `x`"
+
+
+Natural Loops
+
+How to Find Natural Loop?: Introduction Backedge
+
+Important concepts in a loop
+* Header and Loop BB
+* Back Edges
+* Exit Edges
+* Preheader (Preloop)
+
+Loop-Invariant Computation
+
+