move x-x check up front

11 files changed, 44 insertions, 34 deletions

diff --git a/chapter04/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter04/src/main/java/com/seaofnodes/simple/node/SubNode.java
index 27e77f90..58d757ea 100644
--- a/chapter04/src/main/java/com/seaofnodes/simple/node/SubNode.java
+++ b/chapter04/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -19,6 +19,10 @@ public class SubNode extends Node {
 
     @Override
     public Type compute() {
+        // Sub of same is 0
+        if( in(1)==in(2) )
+            return TypeInteger.ZERO;
+
         if (in(1)._type instanceof TypeInteger i0 &&
             in(2)._type instanceof TypeInteger i1) {
             if (i0.isConstant() && i1.isConstant())
@@ -30,10 +34,6 @@ public class SubNode extends Node {
 
     @Override
     public Node idealize() {
-        // Sub of same is 0
-        if( in(1)==in(2) )
-            return new ConstantNode(TypeInteger.constant(0));
-
         return null;
     }
 
diff --git a/chapter05/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter05/src/main/java/com/seaofnodes/simple/node/SubNode.java
index 5e7243ba..475b3790 100644
--- a/chapter05/src/main/java/com/seaofnodes/simple/node/SubNode.java
+++ b/chapter05/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -19,15 +19,16 @@ public class SubNode extends Node {
 
     @Override
     public Type compute() {
+        // Sub of same is 0
+        if( in(1)==in(2) )
+            return TypeInteger.ZERO;
+
         if (in(1)._type instanceof TypeInteger i0 &&
             in(2)._type instanceof TypeInteger i1) {
             if (i0.isConstant() && i1.isConstant())
                 return TypeInteger.constant(i0.value()-i1.value());
             return i0.meet(i1);
         }
-        // Sub of same is 0
-        if( in(1)==in(2) )
-            return TypeInteger.ZERO;
         return Type.BOTTOM;
     }
 
diff --git a/chapter06/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter06/src/main/java/com/seaofnodes/simple/node/SubNode.java
index 5e7243ba..475b3790 100644
--- a/chapter06/src/main/java/com/seaofnodes/simple/node/SubNode.java
+++ b/chapter06/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -19,15 +19,16 @@ public class SubNode extends Node {
 
     @Override
     public Type compute() {
+        // Sub of same is 0
+        if( in(1)==in(2) )
+            return TypeInteger.ZERO;
+
         if (in(1)._type instanceof TypeInteger i0 &&
             in(2)._type instanceof TypeInteger i1) {
             if (i0.isConstant() && i1.isConstant())
                 return TypeInteger.constant(i0.value()-i1.value());
             return i0.meet(i1);
         }
-        // Sub of same is 0
-        if( in(1)==in(2) )
-            return TypeInteger.ZERO;
         return Type.BOTTOM;
     }
 
diff --git a/chapter07/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter07/src/main/java/com/seaofnodes/simple/node/SubNode.java
index 98aa679f..af66b950 100644
--- a/chapter07/src/main/java/com/seaofnodes/simple/node/SubNode.java
+++ b/chapter07/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -21,15 +21,16 @@ public class SubNode extends Node {
 
     @Override
     public Type compute() {
+        // Sub of same is 0
+        if( in(1)==in(2) )
+            return TypeInteger.ZERO;
+
         if (in(1)._type instanceof TypeInteger i0 &&
             in(2)._type instanceof TypeInteger i1) {
             if (i0.isConstant() && i1.isConstant())
                 return TypeInteger.constant(i0.value()-i1.value());
             return i0.meet(i1);
         }
-        // Sub of same is 0
-        if( in(1)==in(2) )
-            return TypeInteger.ZERO;
         return Type.BOTTOM;
     }
 
diff --git a/chapter08/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter08/src/main/java/com/seaofnodes/simple/node/SubNode.java
index 98aa679f..af66b950 100644
--- a/chapter08/src/main/java/com/seaofnodes/simple/node/SubNode.java
+++ b/chapter08/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -21,15 +21,16 @@ public class SubNode extends Node {
 
     @Override
     public Type compute() {
+        // Sub of same is 0
+        if( in(1)==in(2) )
+            return TypeInteger.ZERO;
+
         if (in(1)._type instanceof TypeInteger i0 &&
             in(2)._type instanceof TypeInteger i1) {
             if (i0.isConstant() && i1.isConstant())
                 return TypeInteger.constant(i0.value()-i1.value());
             return i0.meet(i1);
         }
-        // Sub of same is 0
-        if( in(1)==in(2) )
-            return TypeInteger.ZERO;
         return Type.BOTTOM;
     }
 
diff --git a/chapter09/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter09/src/main/java/com/seaofnodes/simple/node/SubNode.java
index 7273c02a..f661be14 100644
--- a/chapter09/src/main/java/com/seaofnodes/simple/node/SubNode.java
+++ b/chapter09/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -21,14 +21,15 @@ public class SubNode extends Node {
 
     @Override
     public Type compute() {
+        // Sub of same is 0
+        if( in(1)==in(2) )
+            return TypeInteger.ZERO;
+
         if (in(1)._type instanceof TypeInteger i0 &&
             in(2)._type instanceof TypeInteger i1) {
             if (i0.isConstant() && i1.isConstant())
                 return TypeInteger.constant(i0.value()-i1.value());
         }
-        // Sub of same is 0
-        if( in(1)==in(2) )
-            return TypeInteger.ZERO;
         return in(1)._type.meet(in(2)._type);
     }
 
diff --git a/chapter10/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter10/src/main/java/com/seaofnodes/simple/node/SubNode.java
index 53f90dd6..b87115cd 100644
--- a/chapter10/src/main/java/com/seaofnodes/simple/node/SubNode.java
+++ b/chapter10/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -21,14 +21,15 @@ public class SubNode extends Node {
 
     @Override
     public Type compute() {
+        // Sub of same is 0
+        if( in(1)==in(2) )
+            return TypeInteger.ZERO;
+
         if (in(1)._type instanceof TypeInteger i0 &&
             in(2)._type instanceof TypeInteger i1) {
             if (i0.isConstant() && i1.isConstant())
                 return TypeInteger.constant(i0.value()-i1.value());
         }
-        // Sub of same is 0
-        if( in(1)==in(2) )
-            return TypeInteger.ZERO;
         return in(1)._type.meet(in(2)._type);
     }
 
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/SubNode.java
index 128678a7..5ddcdb68 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/SubNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -22,14 +22,15 @@ public class SubNode extends Node {
 
     @Override
     public Type compute() {
+        // Sub of same is 0
+        if( in(1)==in(2) )
+            return TypeInteger.ZERO;
+
         if (in(1)._type instanceof TypeInteger i0 &&
             in(2)._type instanceof TypeInteger i1) {
             if (i0.isConstant() && i1.isConstant())
                 return TypeInteger.constant(i0.value()-i1.value());
         }
-        // Sub of same is 0
-        if( in(1)==in(2) )
-            return TypeInteger.ZERO;
         return in(1)._type.meet(in(2)._type);
     }
 
diff --git a/chapter12/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter12/src/main/java/com/seaofnodes/simple/node/SubNode.java
index 8bebe774..f0c77743 100644
--- a/chapter12/src/main/java/com/seaofnodes/simple/node/SubNode.java
+++ b/chapter12/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -22,14 +22,15 @@ public class SubNode extends Node {
 
     @Override
     public Type compute() {
+        // Sub of same is 0
+        if( in(1)==in(2) )
+            return TypeInteger.ZERO;
+
         if (in(1)._type instanceof TypeInteger i0 &&
             in(2)._type instanceof TypeInteger i1) {
             if (i0.isConstant() && i1.isConstant())
                 return TypeInteger.constant(i0.value()-i1.value());
         }
-        // Sub of same is 0
-        if( in(1)==in(2) )
-            return TypeInteger.ZERO;
 
         return in(1)._type.meet(in(2)._type);
     }
diff --git a/chapter13/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter13/src/main/java/com/seaofnodes/simple/node/SubNode.java
index 0f2deb33..81cc6076 100644
--- a/chapter13/src/main/java/com/seaofnodes/simple/node/SubNode.java
+++ b/chapter13/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -22,14 +22,15 @@ public class SubNode extends Node {
 
     @Override
     public Type compute() {
+        // Sub of same is 0
+        if( in(1)==in(2) )
+            return TypeInteger.ZERO;
+
         if (in(1)._type instanceof TypeInteger i0 &&
             in(2)._type instanceof TypeInteger i1) {
             if (i0.isConstant() && i1.isConstant())
                 return TypeInteger.constant(i0.value()-i1.value());
         }
-        // Sub of same is 0
-        if( in(1)==in(2) )
-            return TypeInteger.ZERO;
 
         return in(1)._type.meet(in(2)._type);
     }
diff --git a/chapter14/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter14/src/main/java/com/seaofnodes/simple/node/SubNode.java
index 009fb30e..6d2f1711 100644
--- a/chapter14/src/main/java/com/seaofnodes/simple/node/SubNode.java
+++ b/chapter14/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -22,6 +22,10 @@ public class SubNode extends Node {
 
     @Override
     public Type compute() {
+        // Sub of same is 0
+        if( in(1)==in(2) )
+            return TypeInteger.ZERO;
+
         Type t1 = in(1)._type, t2 = in(2)._type;
         if( t1.isHigh() || t2.isHigh() )
             return TypeInteger.TOP;
@@ -30,9 +34,6 @@ public class SubNode extends Node {
             if (i1.isConstant() && i2.isConstant())
                 return TypeInteger.constant(i1.value()-i2.value());
         }
-        // Sub of same is 0
-        if( in(1)==in(2) )
-            return TypeInteger.ZERO;
 
         return TypeInteger.BOT;
     }