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book.tex

@@ -3014,15 +3014,15 @@ includes the arity.)
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-Based on the liveness analysis, we know where each variable is needed.
-However, during register allocation, we need to answer questions of
-the specific form: are variables $u$ and $v$ live at the same time?
-(And therefore cannot be assigned to the same register.)  To make this
-question easier to answer, we create an explicit data structure, an
-\emph{interference graph}\index{interference graph}.  An interference
-graph is an undirected graph that has an edge between two variables if
-they are live at the same time, that is, if they interfere with each
-other.
+Based on the liveness analysis, we know where each location is used
+(read from).  However, during register allocation, we need to answer
+questions of the specific form: are locations $u$ and $v$ live at the
+same time?  (And therefore cannot be assigned to the same register.)
+To make this question easier to answer, we create an explicit data
+structure, an \emph{interference graph}\index{interference graph}.  An
+interference graph is an undirected graph that has an edge between two
+locations if they are live at the same time, that is, if they
+interfere with each other.
 
 The most obvious way to compute the interference graph is to look at
 the set of live location between each statement in the program and add