Much more robust guarded expression upcasting

Region does not print id, making all test cases much more stable (and slightly weaker).
NotNode gets more precise compute

12 files changed, 58 insertions, 59 deletions

diff --git a/chapter17/src/test/java/com/seaofnodes/simple/Chapter05Test.java b/chapter17/src/test/java/com/seaofnodes/simple/Chapter05Test.java
index b5920125..9afb8f28 100644
--- a/chapter17/src/test/java/com/seaofnodes/simple/Chapter05Test.java
+++ b/chapter17/src/test/java/com/seaofnodes/simple/Chapter05Test.java
@@ -17,12 +17,11 @@ if (arg == 1)
     a = arg+2;
 else {
     a = arg-3;
-
 }
-
-return a;""");
+return a;
+""");
         StopNode ret = parser.parse().iterate();
-        assertEquals("return Phi(Region23,(arg+2),(arg-3));", ret.toString());
+        assertEquals("return Phi(Region,(arg+2),(arg-3));", ret.toString());
     }
 
     @Test
@@ -37,7 +36,7 @@ if (arg == 1) {
 }
 return c;""", TypeInteger.BOT);
         StopNode ret = parser.parse().iterate();
-        assertEquals("return Phi(Region22,4,3);", ret.toString());
+        assertEquals("return Phi(Region,4,3);", ret.toString());
     }
 
     @Test
@@ -65,7 +64,7 @@ else
     b=a+1;
 return a+b;""");
         StopNode ret = parser.parse().iterate();
-        assertEquals("return ((arg*2)+Phi(Region26,2,3));", ret.toString());
+        assertEquals("return ((arg*2)+Phi(Region,2,3));", ret.toString());
     }
 
     @Test
@@ -80,7 +79,7 @@ else
     a=b+1;
 return a+b;""");
         StopNode ret = parser.parse().iterate();
-        assertEquals("return ((Phi(Region37,(arg*2),arg)+arg)+Phi(Region,4,5));", ret.toString());
+        assertEquals("return ((Phi(Region,(arg*2),arg)+arg)+Phi(Region,4,5));", ret.toString());
     }
 
     @Test
@@ -100,7 +99,7 @@ else
 return a;
 """, TypeInteger.BOT);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region43,Phi(Region28,2,3),Phi(Region41,4,5));", stop.toString());
+        assertEquals("return Phi(Region,Phi(Region,2,3),Phi(Region,4,5));", stop.toString());
     }
 
     @Test
@@ -116,7 +115,7 @@ if( arg==0 )
 return arg+a+b;
 """, TypeInteger.BOT);
         StopNode stop = parser.parse();
-        assertEquals("return ((arg+Phi(Region20,1,0))+Phi(Region37,2,0));", stop.toString());
+        assertEquals("return ((arg+Phi(Region,1,0))+Phi(Region,2,0));", stop.toString());
     }
 
     @Test
@@ -130,7 +129,7 @@ if( arg==1 )
 }
 return a;""");
         StopNode ret = parser.parse().iterate();
-        assertEquals("return (arg==Phi(Region22,3,2));", ret.toString());
+        assertEquals("return (arg==Phi(Region,3,2));", ret.toString());
     }
 
     @Test
diff --git a/chapter17/src/test/java/com/seaofnodes/simple/Chapter06Test.java b/chapter17/src/test/java/com/seaofnodes/simple/Chapter06Test.java
index 6308bdea..50c0580d 100644
--- a/chapter17/src/test/java/com/seaofnodes/simple/Chapter06Test.java
+++ b/chapter17/src/test/java/com/seaofnodes/simple/Chapter06Test.java
@@ -65,7 +65,7 @@ else
     b=5;
 return b;""", TypeInteger.BOT);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region43,42,5);", stop.toString());
+        assertEquals("return Phi(Region,42,5);", stop.toString());
     }
 
     @Test
@@ -84,7 +84,7 @@ else
     b=5;
 return b;""", TypeInteger.BOT);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region36,2,5);", stop.toString());
+        assertEquals("return Phi(Region,2,5);", stop.toString());
     }
 
     @Test
@@ -144,7 +144,7 @@ else
 return a;
 """, TypeInteger.BOT);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region48,3,Phi(Region46,4,5));", stop.toString());
+        assertEquals("return Phi(Region,3,Phi(Region,4,5));", stop.toString());
     }
 
     @Test
@@ -200,7 +200,7 @@ if( arg ) {
 return a+b;
 """);
         StopNode ret = parser.parse().iterate();
-        assertEquals("return Phi(Region32,4,1);", ret.toString());
+        assertEquals("return Phi(Region,4,1);", ret.toString());
     }
 
 
@@ -251,7 +251,7 @@ if( arg ) {
 return a+b+c;
 """);
         StopNode ret = parser.parse().iterate();
-        assertEquals("return (Phi(Region45,Phi(Region29,2,3),0)+Phi(Region,3,1));", ret.toString());
+        assertEquals("return (Phi(Region,Phi(Region,2,3),0)+Phi(Region,3,1));", ret.toString());
     }
 
 
diff --git a/chapter17/src/test/java/com/seaofnodes/simple/Chapter07Test.java b/chapter17/src/test/java/com/seaofnodes/simple/Chapter07Test.java
index 80cb15d4..23ad18f1 100644
--- a/chapter17/src/test/java/com/seaofnodes/simple/Chapter07Test.java
+++ b/chapter17/src/test/java/com/seaofnodes/simple/Chapter07Test.java
@@ -18,7 +18,7 @@ public class Chapter07Test {
                 """);
         Node._disablePeephole = true;
         StopNode stop = parser.parse();
-        assertEquals("return Phi(Loop10,arg,(Phi_arg+1));", stop.toString());
+        assertEquals("return Phi(Loop,arg,(Phi_arg+1));", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
         Node._disablePeephole = false;
     }
@@ -36,7 +36,7 @@ if(arg){}else{
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region32,1,Phi(Loop18,1,(Phi_a+1)));", stop.toString());
+        assertEquals("return Phi(Region,1,Phi(Loop,1,(Phi_a+1)));", stop.toString());
     }
 
     @Test
@@ -56,7 +56,7 @@ while(i < arg) {
 return sum;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop12,0,Phi(Loop27,Phi_sum,(Phi_sum+Phi(Loop,0,(Phi_j+1)))));", stop.toString());
+        assertEquals("return Phi(Loop,0,Phi(Loop,Phi_sum,(Phi_sum+Phi(Loop,0,(Phi_j+1)))));", stop.toString());
     }
 
     @Test
@@ -73,7 +73,7 @@ return b;
 """);
         Node._disablePeephole = true;
         StopNode stop = parser.parse();
-        assertEquals("return Phi(Loop12,2,Phi(Region35,Phi_b,4));", stop.toString());
+        assertEquals("return Phi(Loop,2,Phi(Region,Phi_b,4));", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
         Node._disablePeephole = false;
     }
@@ -93,7 +93,7 @@ while(a < 10) {
 return b;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop12,2,(Phi(Region35,Phi_b,4)+1));", stop.toString());
+        assertEquals("return Phi(Loop,2,(Phi(Region,Phi_b,4)+1));", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
     }
 
@@ -111,7 +111,7 @@ return a;
 """);
         Node._disablePeephole = true;
         StopNode stop = parser.parse();
-        assertEquals("return Phi(Loop11,1,((Phi_a+1)+2));", stop.toString());
+        assertEquals("return Phi(Loop,1,((Phi_a+1)+2));", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
         Node._disablePeephole = false;
     }
@@ -128,7 +128,7 @@ while(a < 10) {
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop11,1,(Phi_a+3));", stop.toString());
+        assertEquals("return Phi(Loop,1,(Phi_a+3));", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
     }
 
@@ -142,7 +142,7 @@ return a;
 """);
         Node._disablePeephole = true;
         StopNode stop = parser.parse();
-        assertEquals("return Phi(Loop11,1,2);", stop.toString());
+        assertEquals("return Phi(Loop,1,2);", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
         Node._disablePeephole = false;
     }
@@ -156,7 +156,7 @@ while(arg) a = 2;
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop11,1,2);", stop.toString());
+        assertEquals("return Phi(Loop,1,2);", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
     }
 
@@ -173,7 +173,7 @@ return a;
 """);
         Node._disablePeephole = true;
         StopNode stop = parser.parse();
-        assertEquals("return Phi(Loop11,1,((Phi_a+1)+2));", stop.toString());
+        assertEquals("return Phi(Loop,1,((Phi_a+1)+2));", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
         Node._disablePeephole = false;
     }
@@ -190,7 +190,7 @@ while(a < 10) {
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop11,1,(Phi_a+3));", stop.toString());
+        assertEquals("return Phi(Loop,1,(Phi_a+3));", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
     }
 
@@ -208,7 +208,7 @@ return a;
 """);
         Node._disablePeephole = true;
         StopNode stop = parser.parse();
-        assertEquals("return Phi(Loop12,1,((Phi_a+1)+2));", stop.toString());
+        assertEquals("return Phi(Loop,1,((Phi_a+1)+2));", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
         Node._disablePeephole = false;
     }
@@ -226,7 +226,7 @@ while(a < 10) {
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop12,1,(Phi_a+3));", stop.toString());
+        assertEquals("return Phi(Loop,1,(Phi_a+3));", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
     }
 
diff --git a/chapter17/src/test/java/com/seaofnodes/simple/Chapter08Test.java b/chapter17/src/test/java/com/seaofnodes/simple/Chapter08Test.java
index 5372388b..29fd09dc 100644
--- a/chapter17/src/test/java/com/seaofnodes/simple/Chapter08Test.java
+++ b/chapter17/src/test/java/com/seaofnodes/simple/Chapter08Test.java
@@ -23,7 +23,7 @@ while(arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region46,Phi(Region33,Phi(Loop10,arg,(Phi_arg+1)),Add),Add);", stop.toString());
+        assertEquals("return Phi(Region,Phi(Region,Phi(Loop,arg,(Phi_arg+1)),Add),Add);", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof RegionNode);
         Assert.assertEquals(5L, Evaluator.evaluate(stop, 1));
         Assert.assertEquals(10L, Evaluator.evaluate(stop, 6));
@@ -46,7 +46,7 @@ while(arg < 10) {
 return a;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop11,1,Phi(Region53,Phi_a,(Phi_a+1)));", stop.toString());
+        assertEquals("return Phi(Loop,1,Phi(Region,Phi_a,(Phi_a+1)));", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
     }
 
@@ -65,7 +65,7 @@ while(arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region44,Phi(Loop10,arg,(Phi_arg+1)),Add);", stop.toString());
+        assertEquals("return Phi(Region,Phi(Loop,arg,(Phi_arg+1)),Add);", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof RegionNode);
     }
 
@@ -81,7 +81,7 @@ while(arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region33,Phi(Loop10,arg,(Phi_arg+1)),Add);", stop.toString());
+        assertEquals("return Phi(Region,Phi(Loop,arg,(Phi_arg+1)),Add);", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof RegionNode);
     }
 
@@ -100,7 +100,7 @@ while(arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop10,arg,(Phi_arg+1));", stop.toString());
+        assertEquals("return Phi(Loop,arg,(Phi_arg+1));", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
     }
 
@@ -117,7 +117,7 @@ while(arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop10,arg,(Phi_arg+1));", stop.toString());
+        assertEquals("return Phi(Loop,arg,(Phi_arg+1));", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode);
     }
 
@@ -185,7 +185,7 @@ while(arg < 10) {
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region36,Phi(Loop11,1,(Phi_a+1)),Add);", stop.toString());
+        assertEquals("return Phi(Region,Phi(Loop,1,(Phi_a+1)),Add);", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof RegionNode);
     }
 
@@ -201,7 +201,7 @@ while(1) {
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return (Phi(Loop11,1,Add)+1);", stop.toString());
+        assertEquals("return (Phi(Loop,1,Add)+1);", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof CProjNode prj && prj._idx==1 );
     }
 
diff --git a/chapter17/src/test/java/com/seaofnodes/simple/Chapter09Test.java b/chapter17/src/test/java/com/seaofnodes/simple/Chapter09Test.java
index 04ab8001..c31afcd6 100644
--- a/chapter17/src/test/java/com/seaofnodes/simple/Chapter09Test.java
+++ b/chapter17/src/test/java/com/seaofnodes/simple/Chapter09Test.java
@@ -69,7 +69,7 @@ while (arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop11,arg,(Phi_arg+2));", stop.toString());
+        assertEquals("return Phi(Loop,arg,(Phi_arg+2));", stop.toString());
         Assert.assertEquals(11L, Evaluator.evaluate(stop, 1));
     }
 
@@ -86,7 +86,7 @@ while (arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop12,arg,(Phi_arg+4));", stop.toString());
+        assertEquals("return Phi(Loop,arg,(Phi_arg+4));", stop.toString());
         Assert.assertEquals(13L, Evaluator.evaluate(stop, 1));
     }
 
@@ -185,7 +185,7 @@ while(arg) {
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop13,0,(-(Phi_a+3)));", stop.toString());
+        assertEquals("return Phi(Loop,0,(-(Phi_a+3)));", stop.toString());
     }
 
     @Test
diff --git a/chapter17/src/test/java/com/seaofnodes/simple/Chapter10Test.java b/chapter17/src/test/java/com/seaofnodes/simple/Chapter10Test.java
index 0bf921f6..44d71b1e 100644
--- a/chapter17/src/test/java/com/seaofnodes/simple/Chapter10Test.java
+++ b/chapter17/src/test/java/com/seaofnodes/simple/Chapter10Test.java
@@ -104,7 +104,7 @@ while (arg) {
 return bar.a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop16,0,(Phi_a+2));", stop.toString());
+        assertEquals("return Phi(Loop,0,(Phi_a+2));", stop.toString());
     }
 
     @Test
@@ -156,7 +156,7 @@ if( bar ) bar.a = 1;
 return bar;
 """);
         StopNode stop = parser.parse(false).iterate();
-        assertEquals("return Phi(Region38,(*void)Phi(Region24,null,Bar),null);", stop.toString());
+        assertEquals("return Phi(Region,(*void)Phi(Region,null,Bar),null);", stop.toString());
     }
 
     @Test
@@ -172,7 +172,7 @@ else bar.a = 1;
 return rez;
 """);
         StopNode stop = parser.parse(false).iterate();
-        assertEquals("return Phi(Region44,4,3);", stop.toString());
+        assertEquals("return Phi(Region,4,3);", stop.toString());
     }
 
     @Test
@@ -226,7 +226,7 @@ while( i.x < i.len ) {
 return sum;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop21,0,(Phi(Loop,0,(Phi_x+1))+Phi_sum));", stop.toString());
+        assertEquals("return Phi(Loop,0,(Phi(Loop,0,(Phi_x+1))+Phi_sum));", stop.toString());
     }
 
 
@@ -245,7 +245,7 @@ while(arg) {
 return ret;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop16,s0,Phi(Region45,s0,Phi_ret));", stop.toString());
+        assertEquals("return Phi(Loop,s0,Phi(Region,s0,Phi_ret));", stop.toString());
     }
 
     @Test
@@ -263,7 +263,7 @@ while(arg) {
 return ret;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop20,s0,Phi(Region46,s0,Phi_ret));", stop.toString());
+        assertEquals("return Phi(Loop,s0,Phi(Region,s0,Phi_ret));", stop.toString());
     }
 
 
@@ -280,7 +280,7 @@ while(arg < 10) {
 return ret;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop16,s0,Phi(Region42,s0,Phi_ret));", stop.toString());
+        assertEquals("return Phi(Loop,s0,Phi(Region,s0,Phi_ret));", stop.toString());
     }
 
     @Test
diff --git a/chapter17/src/test/java/com/seaofnodes/simple/Chapter11Test.java b/chapter17/src/test/java/com/seaofnodes/simple/Chapter11Test.java
index 44814d53..11424720 100644
--- a/chapter17/src/test/java/com/seaofnodes/simple/Chapter11Test.java
+++ b/chapter17/src/test/java/com/seaofnodes/simple/Chapter11Test.java
@@ -324,7 +324,7 @@ while( prime <= arg ) {
 return primeCount;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("Stop[ return 0; return Phi(Loop23,1,Phi(Region102,Phi_primeCount,Phi(Region95,(Phi_primeCount+1),Phi_primeCount))); ]", stop.toString());
+        assertEquals("Stop[ return 0; return Phi(Loop,1,Phi(Region,Phi_primeCount,Phi(Region,(Phi_primeCount+1),Phi_primeCount))); ]", stop.toString());
         assertEquals(0L, Evaluator.evaluate(stop,  1)); // No primes 1 or below
         assertEquals(1L, Evaluator.evaluate(stop,  2)); // 2
         assertEquals(2L, Evaluator.evaluate(stop,  3)); // 2, 3
@@ -369,7 +369,7 @@ if (arg) {
 return i;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region45,.f,0);", stop.toString());
+        assertEquals("return Phi(Region,.f,0);", stop.toString());
     }
 
     @Test
diff --git a/chapter17/src/test/java/com/seaofnodes/simple/Chapter12Test.java b/chapter17/src/test/java/com/seaofnodes/simple/Chapter12Test.java
index c0f6266a..a70a5f33 100644
--- a/chapter17/src/test/java/com/seaofnodes/simple/Chapter12Test.java
+++ b/chapter17/src/test/java/com/seaofnodes/simple/Chapter12Test.java
@@ -43,7 +43,7 @@ while( 1 ) {
 return guess;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop11,(flt)arg,(((ToFloat/Phi_guess)+Phi_guess)/2.0));", stop.toString());
+        assertEquals("return Phi(Loop,(flt)arg,(((ToFloat/Phi_guess)+Phi_guess)/2.0));", stop.toString());
         assertEquals(3.0, Evaluator.evaluate(stop,  9));
         assertEquals(1.414213562373095, Evaluator.evaluate(stop,  2));
     }
diff --git a/chapter17/src/test/java/com/seaofnodes/simple/Chapter14Test.java b/chapter17/src/test/java/com/seaofnodes/simple/Chapter14Test.java
index e72b0c76..01cecebb 100644
--- a/chapter17/src/test/java/com/seaofnodes/simple/Chapter14Test.java
+++ b/chapter17/src/test/java/com/seaofnodes/simple/Chapter14Test.java
@@ -175,7 +175,7 @@ while(v1) break;
 return v1;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return (Phi(Loop18,((1<<arg)&1),0)&Phi(Loop,Shl,4294967295));", stop.toString());
+        assertEquals("return (Phi(Loop,((1<<arg)&1),0)&Phi(Loop,Shl,4294967295));", stop.toString());
         assertEquals(1L, Evaluator.evaluate(stop,  0));
     }
 
diff --git a/chapter17/src/test/java/com/seaofnodes/simple/Chapter15Test.java b/chapter17/src/test/java/com/seaofnodes/simple/Chapter15Test.java
index 4226c201..04958819 100644
--- a/chapter17/src/test/java/com/seaofnodes/simple/Chapter15Test.java
+++ b/chapter17/src/test/java/com/seaofnodes/simple/Chapter15Test.java
@@ -130,7 +130,7 @@ else {
 return rez;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region117,1.2,Phi(Region114,2.3,3.14));", stop.toString());
+        assertEquals("return Phi(Region,1.2,Phi(Region,2.3,3.14));", stop.toString());
         assertEquals(3.14, Evaluator.evaluate(stop, 0));
         assertEquals(1.2 , Evaluator.evaluate(stop, 1));
     }
@@ -157,7 +157,7 @@ if( iss[arg] )
 return rez;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region122,Phi(Region118,.y,1.2),1.2);", stop.toString());
+        assertEquals("return Phi(Region,Phi(Region,.y,1.2),1.2);", stop.toString());
         assertEquals(3.14, Evaluator.evaluate(stop, 0));
     }
 
diff --git a/chapter17/src/test/java/com/seaofnodes/simple/Chapter16Test.java b/chapter17/src/test/java/com/seaofnodes/simple/Chapter16Test.java
index be48ec55..d0e30a7c 100644
--- a/chapter17/src/test/java/com/seaofnodes/simple/Chapter16Test.java
+++ b/chapter17/src/test/java/com/seaofnodes/simple/Chapter16Test.java
@@ -64,7 +64,7 @@ if( arg ) { int x = y; x = x*x; y=x; } // Shadow final x
 return y;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region21,9,3);", stop.toString());
+        assertEquals("return Phi(Region,9,3);", stop.toString());
         assertEquals(3L, Evaluator.evaluate(stop, 0));
         assertEquals(9L, Evaluator.evaluate(stop, 1));
     }
diff --git a/chapter17/src/test/java/com/seaofnodes/simple/Chapter17Test.java b/chapter17/src/test/java/com/seaofnodes/simple/Chapter17Test.java
index 5db9592e..fe275ee9 100644
--- a/chapter17/src/test/java/com/seaofnodes/simple/Chapter17Test.java
+++ b/chapter17/src/test/java/com/seaofnodes/simple/Chapter17Test.java
@@ -105,7 +105,7 @@ return d;
 return arg ? 1 : 2;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region19,1,2);", stop.toString());
+        assertEquals("return Phi(Region,1,2);", stop.toString());
         assertEquals(2L, Evaluator.evaluate(stop, 0));
         assertEquals(1L, Evaluator.evaluate(stop, 1));
     }
@@ -128,7 +128,7 @@ var b = arg ? new Bar : null;
 return b ? b.x++ + b.x++ : -1;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region54,1,-1);", stop.toString());
+        assertEquals("return Phi(Region,1,-1);", stop.toString());
         assertEquals(-1L, Evaluator.evaluate(stop, 0));
         assertEquals( 1L, Evaluator.evaluate(stop, 1));
     }
@@ -141,21 +141,21 @@ var b = arg ? new Bar;
 return b ? b.x++ + b.x++ : -1;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region54,1,-1);", stop.toString());
+        assertEquals("return Phi(Region,1,-1);", stop.toString());
         assertEquals(-1L, Evaluator.evaluate(stop, 0));
         assertEquals( 1L, Evaluator.evaluate(stop, 1));
     }
 
-    @Ignore
     @Test
     public void testTrinary4() {
+        // This test case will benefit from an unzipping transformation
         Parser parser = new Parser("""
 struct Bar { Bar? next; int x; };
 var b = arg ? new Bar { next = (arg==2) ? new Bar{x=2;}; x=1; };
 return b ? b.next ? b.next.x : b.x; // parses "b ? (b.next ? b.next.x : b.x) : 0"
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region51,1,-1);", stop.toString());
+        assertEquals("return Phi(Region,Phi(Region,.x,.x),0);", stop.toString());
         assertEquals( 0L, Evaluator.evaluate(stop, 0));
         assertEquals( 1L, Evaluator.evaluate(stop, 1));
         assertEquals( 2L, Evaluator.evaluate(stop, 2));
@@ -178,7 +178,7 @@ while( head ) {
 return sum;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop35,0,(Phi_sum+.i));", stop.toString());
+        assertEquals("return Phi(Loop,0,(Phi_sum+.i));", stop.toString());
         assertEquals(45L, Evaluator.evaluate(stop, 10));
     }