From 18fd28edce813d36c491e42d9e64c53c7251d26e Mon Sep 17 00:00:00 2001
From: Cliff Click <cliffc@acm.org>
Date: Fri, 7 Feb 2025 08:58:36 -0800
Subject: Chapter 19: Instruction Selection and Portable Compilation
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: Tamás Hadházy <85063808+Hels15@users.noreply.github.com>
Co-authored-by: Hsiang-Ying Fu <66062782+fuhsnn@users.noreply.github.com>
Co-authored-by: hadha <helsgithub15@gmail.com>
Co-authored-by: godalming123 <68993177+godalming123@users.noreply.github.com>
Co-authored-by: fuhsnn <66062782+fuhsnn@users.noreply.github.com>
Co-authored-by: Symious <14933944+symious@users.noreply.github.com>
Co-authored-by: RobertObkircher <robert.obkircher@gmail.com>
Co-authored-by: Jun Kawasaki <jun784@gmail.com>
Co-authored-by: Claude Opus 5 <noreply@anthropic.com>
---
 .../java/com/seaofnodes/simple/BrainFuckTest.java  |   2 +-
 .../java/com/seaofnodes/simple/Chapter03Test.java  |   2 +-
 .../java/com/seaofnodes/simple/Chapter04Test.java  |  21 +-
 .../java/com/seaofnodes/simple/Chapter05Test.java  |  64 +--
 .../java/com/seaofnodes/simple/Chapter06Test.java  |  30 +-
 .../java/com/seaofnodes/simple/Chapter08Test.java  |   4 +-
 .../java/com/seaofnodes/simple/Chapter09Test.java  |   4 +-
 .../java/com/seaofnodes/simple/Chapter11Test.java  |  10 +-
 .../java/com/seaofnodes/simple/Chapter12Test.java  |   2 +-
 .../java/com/seaofnodes/simple/Chapter15Test.java  |  12 +-
 .../java/com/seaofnodes/simple/Chapter17bTest.java |   8 +-
 .../java/com/seaofnodes/simple/Chapter18Test.java  |  58 +--
 .../java/com/seaofnodes/simple/Chapter19Test.java  | 529 +++++++++++++++++++++
 src/test/java/com/seaofnodes/simple/Eval2.java     |   6 +-
 .../java/com/seaofnodes/simple/FuzzerWrap.java     |   7 +-
 src/test/java/com/seaofnodes/simple/Main.java      |  17 +
 .../com/seaofnodes/simple/evaluator/Evaluator.java |  13 +-
 .../com/seaofnodes/simple/evaluator/Scheduler.java |   2 +-
 .../java/com/seaofnodes/simple/fuzzer/Fuzzer.java  |  15 +-
 .../com/seaofnodes/simple/fuzzer/FuzzerUtils.java  |  36 +-
 .../seaofnodes/simple/fuzzer/ScriptGenerator.java  |  16 +-
 src/test/java/com/seaofnodes/simple/progs/fcn.smp  |  15 +
 src/test/java/com/seaofnodes/simple/progs/fcn2.smp |   5 +
 src/test/java/com/seaofnodes/simple/progs/fcn3.smp |  42 ++
 .../java/com/seaofnodes/simple/progs/sieve.smp     |  32 ++
 25 files changed, 758 insertions(+), 194 deletions(-)
 create mode 100644 src/test/java/com/seaofnodes/simple/Chapter19Test.java
 create mode 100644 src/test/java/com/seaofnodes/simple/Main.java
 create mode 100644 src/test/java/com/seaofnodes/simple/progs/fcn.smp
 create mode 100644 src/test/java/com/seaofnodes/simple/progs/fcn2.smp
 create mode 100644 src/test/java/com/seaofnodes/simple/progs/fcn3.smp
 create mode 100644 src/test/java/com/seaofnodes/simple/progs/sieve.smp

(limited to 'src/test/java/com/seaofnodes/simple')

diff --git a/src/test/java/com/seaofnodes/simple/BrainFuckTest.java b/src/test/java/com/seaofnodes/simple/BrainFuckTest.java
index 37ecde1c..8f09cb3d 100644
--- a/src/test/java/com/seaofnodes/simple/BrainFuckTest.java
+++ b/src/test/java/com/seaofnodes/simple/BrainFuckTest.java
@@ -63,7 +63,7 @@ for( int pc = 0; pc < program#; pc++ ) {
 }
 return output;
                 """);
-        code.parse().opto().typeCheck().GCM();
+        code.parse().opto().typeCheck()/*.instSelect("x86_64_v2", "SystemV")*/.GCM().localSched();
         assertEquals("Hello World!\n", Eval2.eval(code, 0, 10000));
     }
 }
diff --git a/src/test/java/com/seaofnodes/simple/Chapter03Test.java b/src/test/java/com/seaofnodes/simple/Chapter03Test.java
index 409e23ed..8212d246 100644
--- a/src/test/java/com/seaofnodes/simple/Chapter03Test.java
+++ b/src/test/java/com/seaofnodes/simple/Chapter03Test.java
@@ -46,7 +46,7 @@ public class Chapter03Test {
     @Test
     public void testRedeclareVar() {
         try {
-            new Parser("int a=1; int b=2; int c=0; int b=3; c=a+b;").parse();
+            new CodeGen("int a=1; int b=2; int c=0; int b=3; c=a+b;").parse();
             fail();
         } catch( RuntimeException e ) {
             assertEquals("Redefining name 'b'",e.getMessage());
diff --git a/src/test/java/com/seaofnodes/simple/Chapter04Test.java b/src/test/java/com/seaofnodes/simple/Chapter04Test.java
index d2260e1f..934e794f 100644
--- a/src/test/java/com/seaofnodes/simple/Chapter04Test.java
+++ b/src/test/java/com/seaofnodes/simple/Chapter04Test.java
@@ -34,14 +34,14 @@ public class Chapter04Test {
     public void testAddAddMul() {
         CodeGen code = new CodeGen("return arg+0+arg;");
         code.parse();
-        assertEquals("return (arg*2);", code.print());
+        assertEquals("return (arg<<1);", code.print());
     }
 
     @Test
     public void testPeephole3() {
         CodeGen code = new CodeGen("return 1+arg+2+arg+3; ");
         code.parse();
-        assertEquals("return ((arg*2)+6);", code.print());
+        assertEquals("return ((arg<<1)+6);", code.print());
     }
 
     @Test
@@ -90,8 +90,7 @@ public class Chapter04Test {
     // Adding functions means `main` does not constant fold the incoming arg value
     @Ignore @Test
     public void testConstantArg() {
-        CodeGen code = new CodeGen("return arg; ", TypeInteger.constant(2));
-        code.parse();
+        CodeGen code = new CodeGen("return arg; ", TypeInteger.constant(2), 123L).parse();
         assertEquals("return 2;", code.expr().in(1).toString());
     }
 
@@ -139,12 +138,8 @@ public class Chapter04Test {
 
     @Test
     public void testBug3() {
-        try {
-            new Parser("inta=1; return a;").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Undefined name 'inta'",e.getMessage());
-        }
+        try { new CodeGen("inta=1; return a;").parse(); fail(); }
+        catch( RuntimeException e ) { assertEquals("Undefined name 'inta'",e.getMessage()); }
     }
 
     @Test
@@ -156,8 +151,8 @@ public class Chapter04Test {
 
     @Test
     public void testBug5() {
-        Parser parser = new Parser("return arg--2;");
-        StopNode ret = parser.parse();
-        assertEquals("return (arg--2);", ret.print());
+        CodeGen code = new CodeGen("return arg--2;");
+        code.parse();
+        assertEquals("return (arg--2);", code.print());
     }
 }
diff --git a/src/test/java/com/seaofnodes/simple/Chapter05Test.java b/src/test/java/com/seaofnodes/simple/Chapter05Test.java
index ff60c695..7a9414a2 100644
--- a/src/test/java/com/seaofnodes/simple/Chapter05Test.java
+++ b/src/test/java/com/seaofnodes/simple/Chapter05Test.java
@@ -64,7 +64,7 @@ else
     b=a+1;
 return a+b;""");
         code.parse().opto();
-        assertEquals("return ((arg*2)+Phi(Region,2,3));", code.print());
+        assertEquals("return ((arg<<1)+Phi(Region,2,3));", code.print());
     }
 
     @Test
@@ -79,7 +79,7 @@ else
     a=b+1;
 return a+b;""");
         code.parse().opto();
-        assertEquals("return ((Phi(Region,(arg*2),arg)+arg)+Phi(Region,4,5));", code.print());
+        assertEquals("return ((Phi(Region,(arg<<1),arg)+arg)+Phi(Region,4,5));", code.print());
     }
 
     @Test
@@ -150,79 +150,51 @@ return a;
 
     @Test
     public void testTrue() {
-      StopNode stop = new Parser("return true;").parse();
-      assertEquals("return 1;",stop.ret().print());
+      CodeGen code = new CodeGen("return true;").parse();
+      assertEquals("return 1;",code.print());
     }
 
     @Test
     public void testHalfDef() {
-        try {
-            new CodeGen("if( arg==1 ) int b=2; return b;").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Cannot define a 'b' on one arm of an if",e.getMessage());
-        }
+        try { new CodeGen("if( arg==1 ) int b=2; return b;").parse(); fail(); }
+        catch( RuntimeException e ) { assertEquals("Cannot define a 'b' on one arm of an if",e.getMessage()); }
     }
 
     @Test
     public void testHalfDef2() {
-        try {
-            new Parser("if( arg==1 ) { int b=2; } else { int b=3; } return b;").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Undefined name 'b'",e.getMessage());
-        }
+        try { new CodeGen("if( arg==1 ) { int b=2; } else { int b=3; } return b;").parse(); fail(); }
+        catch( RuntimeException e ) { assertEquals("Undefined name 'b'",e.getMessage()); }
     }
 
     @Test
     public void testRegress1() {
-        try {
-            new CodeGen("if(arg==2) int a=1; else int b=2; return a;").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Cannot define a 'a' on one arm of an if",e.getMessage());
-        }
+        try { new CodeGen("if(arg==2) int a=1; else int b=2; return a;").parse(); fail(); }
+        catch( RuntimeException e ) { assertEquals("Cannot define a 'a' on one arm of an if",e.getMessage()); }
     }
 
 
     @Test
     public void testBadNum() {
-        try {
-            new Parser("return 1-;").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Syntax error, expected an identifier or expression: ;",e.getMessage());
-        }
+        try { new CodeGen("return 1-;").parse();  fail(); }
+        catch( RuntimeException e ) { assertEquals("Syntax error, expected an identifier or expression: ;",e.getMessage()); }
     }
 
     @Test
     public void testKeyword1() {
-        try {
-            new Parser("int true=0; return true;").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Expected an identifier, found 'true'",e.getMessage());
-        }
+        try { new CodeGen("int true=0; return true;").parse(); fail(); }
+        catch( RuntimeException e ) { assertEquals("Expected an identifier, found 'true'",e.getMessage()); }
     }
 
     @Test
     public void testKeyword2() {
-        try {
-            new Parser("int else=arg; if(else) else=2; else else=1; return else;").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Expected an identifier, found 'else'",e.getMessage());
-        }
+        try { new CodeGen("int else=arg; if(else) else=2; else else=1; return else;").parse(); fail(); }
+        catch( RuntimeException e ) { assertEquals("Expected an identifier, found 'else'",e.getMessage()); }
     }
 
     @Test
     public void testKeyword3() {
-        try {
-            new CodeGen("int a=1; ififif(arg);a=2;return a;").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Undefined name 'ififif'",e.getMessage());
-        }
+        try { new CodeGen("int a=1; ififif(arg);a=2;return a;").parse(); fail(); }
+        catch( RuntimeException e ) { assertEquals("Undefined name 'ififif'",e.getMessage()); }
     }
 
 }
diff --git a/src/test/java/com/seaofnodes/simple/Chapter06Test.java b/src/test/java/com/seaofnodes/simple/Chapter06Test.java
index 2107cdb0..117531f0 100644
--- a/src/test/java/com/seaofnodes/simple/Chapter06Test.java
+++ b/src/test/java/com/seaofnodes/simple/Chapter06Test.java
@@ -103,8 +103,7 @@ else if( arg==3 )
 else
     a=5;
 return a;
-""", TypeInteger.constant(2));
-        code.parse().opto();
+""", TypeInteger.constant(2), 123L).parse().opto();
         assertEquals("return 5;", code.print());
     }
 
@@ -124,8 +123,7 @@ else if( arg==3 )
 else
     a=5;
 return a;
-""", TypeInteger.constant(1));
-        code.parse().opto();
+""", TypeInteger.constant(1), 123L).parse().opto();
         assertEquals("return 3;", code.print());
     }
 
@@ -165,7 +163,7 @@ else if( arg==3 )
 else
     a=5;
 return a;
-""", TypeInteger.constant(1));
+""", TypeInteger.constant(1), 123L);
         code.parse().opto();
         assertEquals("return 3;", code.print());
     }
@@ -186,7 +184,7 @@ else if( arg==3 )
 else
     a=5;
 return a;
-""", TypeInteger.constant(3));
+""", TypeInteger.constant(3), 123L);
         code.parse().opto();
         assertEquals("return 4;", code.print());
     }
@@ -210,7 +208,8 @@ return a+b;
 
     @Test
     public void testDemo1True() {
-        CodeGen code = new CodeGen("""
+        CodeGen code = new CodeGen(
+"""
 arg=1;
 int a = 0;
 int b = 1;
@@ -220,14 +219,15 @@ if( arg ) {
     else b = 3;
 }
 return a+b;
-""", TypeInteger.constant(1));
+""", TypeInteger.constant(1), 123L);
         code.parse().opto();
         assertEquals("return 4;", code.print());
     }
 
     @Test
     public void testDemo1False() {
-        CodeGen code = new CodeGen("""
+        CodeGen code = new CodeGen(
+"""
 arg=0;
 int a = 0;
 int b = 1;
@@ -237,7 +237,7 @@ if( arg ) {
     else b = 3;
 }
 return a+b;
-""", TypeInteger.constant(0));
+""", TypeInteger.constant(0), 123L);
         code.parse().opto();
         assertEquals("return 1;", code.print());
     }
@@ -263,7 +263,8 @@ return a+b+c;
 
     @Test
     public void testDemo2True() {
-        CodeGen code = new CodeGen("""
+        CodeGen code = new CodeGen(
+"""
 arg=1;
 int a = 0;
 int b = 1;
@@ -275,14 +276,15 @@ if( arg ) {
     else b = 3;
 }
 return a+b+c;
-""", TypeInteger.constant(1));
+""", TypeInteger.constant(1), 123L);
         code.parse().opto();
         assertEquals("return 6;", code.print());
     }
 
     @Test
     public void testDemo2arg2() {
-        CodeGen code = new CodeGen("""
+        CodeGen code = new CodeGen(
+"""
 arg=2;
 int a = 0;
 int b = 1;
@@ -294,7 +296,7 @@ if( arg ) {
     else b = 3;
 }
 return a+b+c;
-""", TypeInteger.constant(2));
+""", TypeInteger.constant(2), 123L);
         code.parse().opto();
         assertEquals("return 5;", code.print());
     }
diff --git a/src/test/java/com/seaofnodes/simple/Chapter08Test.java b/src/test/java/com/seaofnodes/simple/Chapter08Test.java
index 03a2c50a..350df18b 100644
--- a/src/test/java/com/seaofnodes/simple/Chapter08Test.java
+++ b/src/test/java/com/seaofnodes/simple/Chapter08Test.java
@@ -1,8 +1,6 @@
 package com.seaofnodes.simple;
 
-import com.seaofnodes.simple.evaluator.Evaluator;
 import com.seaofnodes.simple.node.*;
-import com.seaofnodes.simple.type.TypeInteger;
 import org.junit.Assert;
 import org.junit.Test;
 
@@ -147,7 +145,7 @@ return arg;
     @Test
     public void testBreakOutsideLoop() {
         try {
-            new Parser("""
+            new CodeGen("""
 if(arg <= 10) {
     break;
     arg = arg + 1;
diff --git a/src/test/java/com/seaofnodes/simple/Chapter09Test.java b/src/test/java/com/seaofnodes/simple/Chapter09Test.java
index b210f7e9..10f4a78b 100644
--- a/src/test/java/com/seaofnodes/simple/Chapter09Test.java
+++ b/src/test/java/com/seaofnodes/simple/Chapter09Test.java
@@ -41,7 +41,7 @@ else {
 return x;
                 """);
         code.parse().opto();
-        assertEquals("return Phi(Region,(arg*2),(Mul+1));", code.print());
+        assertEquals("return Phi(Region,(arg<<1),(Shl+1));", code.print());
         Assert.assertEquals( "2", Eval2.eval(code,  1));
         Assert.assertEquals("23", Eval2.eval(code, 11));
     }
@@ -255,7 +255,7 @@ while(0==1) while(v0)
         v0=1+v0;
 """);
         code.parse().opto();
-        assertEquals("return ~int;", code.print());
+        assertEquals("return 0;", code.print());
     }
 
     @Test
diff --git a/src/test/java/com/seaofnodes/simple/Chapter11Test.java b/src/test/java/com/seaofnodes/simple/Chapter11Test.java
index 9fd392d2..14819869 100644
--- a/src/test/java/com/seaofnodes/simple/Chapter11Test.java
+++ b/src/test/java/com/seaofnodes/simple/Chapter11Test.java
@@ -48,17 +48,11 @@ public class Chapter11Test {
         assertEquals("S{x=1,y=2,z=3}",Eval2.eval(code,4));
     }
 
-    @Test public void testLateSliceWorklist() throws ReflectiveOperationException {
+    @Test public void testLateSliceWorklist() {
         // Seed 97 exposed a store selecting a bulk predecessor without queuing
         // it. Keep both the worklist assertion and the final heap check.
         for (int seed : new int[]{0,97,123,456}) {
-            var code = new CodeGen(Chapter10Test.NESTED_MEMORY).parse();
-            var field = IterPeeps.class.getDeclaredField("WORK");
-            field.setAccessible(true);
-            Object work = field.get(null);
-            field = work.getClass().getDeclaredField("_R");
-            field.setAccessible(true);
-            ((java.util.Random)field.get(work)).setSeed(seed);
+            var code = new CodeGen(Chapter10Test.NESTED_MEMORY,com.seaofnodes.simple.type.TypeInteger.BOT,seed).parse();
             code.opto();
             assertEquals("S{x=9,y=25,z=17}",Eval2.eval(code,4));
         }
diff --git a/src/test/java/com/seaofnodes/simple/Chapter12Test.java b/src/test/java/com/seaofnodes/simple/Chapter12Test.java
index a15132d4..90aaf631 100644
--- a/src/test/java/com/seaofnodes/simple/Chapter12Test.java
+++ b/src/test/java/com/seaofnodes/simple/Chapter12Test.java
@@ -183,7 +183,7 @@ return new S1.s=new S2;
 struct I {int i;};
 struct P { !I? !pi; };
 !P !p1 = new P;
-!P p2 = new P;
+!P !p2 = new P;
 p2.pi = new I;
 p2.pi.i = 2;
 if (arg) p1 = new P;
diff --git a/src/test/java/com/seaofnodes/simple/Chapter15Test.java b/src/test/java/com/seaofnodes/simple/Chapter15Test.java
index 97f695bf..c38dfb00 100644
--- a/src/test/java/com/seaofnodes/simple/Chapter15Test.java
+++ b/src/test/java/com/seaofnodes/simple/Chapter15Test.java
@@ -142,7 +142,7 @@ struct S { int x; flt y; };
 !S !s = new S; s.x=99; s.y = 3.14;
 
 // Double-d array of Ss.  Fill in one row.
-!S?[]?[] iss = new !S?[]?[2];
+!S?[]?[] !iss = new !S?[]?[2];
 iss[0] = new !S?[7];
 iss[0][2] = s;
 
@@ -151,10 +151,12 @@ flt rez = 1.2;
 if( iss[arg] )
     if( iss[arg][2] )
         rez = iss[arg][2].y;
-return rez;
-""");
-        try { code.parse().opto().typeCheck(); fail(); }
-        catch( Exception e ) { assertEquals("Might be null accessing '[]'",e.getMessage()); }
+return rez;""");
+        code.parse().opto().typeCheck();
+        assertEquals("return Phi(Region,Phi(Region,.y,1.2),1.2);", code.print());
+        assertEquals("3.14", Eval2.eval(code,  0));
+        try { Eval2.eval(code, 10); fail(); } // Fails AIOOBE in Eval2, no range checks
+        catch( Exception e ) { assertEquals("Index 10 out of bounds for length 2",e.getMessage()); }
     }
 
     @Test
diff --git a/src/test/java/com/seaofnodes/simple/Chapter17bTest.java b/src/test/java/com/seaofnodes/simple/Chapter17bTest.java
index e83b43af..19cc25d9 100644
--- a/src/test/java/com/seaofnodes/simple/Chapter17bTest.java
+++ b/src/test/java/com/seaofnodes/simple/Chapter17bTest.java
@@ -39,7 +39,7 @@ return arg++;
 return arg+++arg++;
 """);
         code.parse().opto();
-        assertEquals("return ((arg*2)+1);", code.print());
+        assertEquals("return ((arg<<1)+1);", code.print());
         assertEquals("1", Eval2.eval(code, 0));
     }
 
@@ -50,7 +50,7 @@ return arg+++arg++;
 return -arg---arg--;
 """);
         code.parse().opto();
-        assertEquals("return (-((arg*2)+-1));", code.print());
+        assertEquals("return (-((arg<<1)+-1));", code.print());
         assertEquals("1", Eval2.eval(code, 0));
     }
 
@@ -344,7 +344,7 @@ var b = arg ? new Bar : null;
 return b ? b.x++ + b.x++ : -1;
 """);
         code.parse().opto();
-        assertEquals("return Phi(Region,((.x*2)+1),-1);", code.print());
+        assertEquals("return Phi(Region,((.x<<1)+1),-1);", code.print());
         assertEquals("-1", Eval2.eval(code, 0));
         assertEquals("1", Eval2.eval(code, 1));
     }
@@ -357,7 +357,7 @@ var b = arg ? new Bar;
 return b ? b.x++ + b.x++ : -1;
 """);
         code.parse().opto();
-        assertEquals("return Phi(Region,((.x*2)+1),-1);", code.print());
+        assertEquals("return Phi(Region,((.x<<1)+1),-1);", code.print());
         assertEquals("-1", Eval2.eval(code, 0));
         assertEquals("1", Eval2.eval(code, 1));
     }
diff --git a/src/test/java/com/seaofnodes/simple/Chapter18Test.java b/src/test/java/com/seaofnodes/simple/Chapter18Test.java
index 7f2b92ac..f965edd4 100644
--- a/src/test/java/com/seaofnodes/simple/Chapter18Test.java
+++ b/src/test/java/com/seaofnodes/simple/Chapter18Test.java
@@ -9,30 +9,6 @@ import static org.junit.Assert.fail;
 import org.junit.Ignore;
 
 public class Chapter18Test {
-    @Test public void testFloatArrays() {
-        for( String type : new String[]{"flt","f64","f32"} ) {
-            CodeGen zero = new CodeGen("var a = new "+type+"[arg]; return a[arg-1];")
-                .parse().opto().typeCheck();
-            assertEquals("0.0",Eval2.eval(zero,3));
-            new CodeGen(type+" x = arg; var a = new "+type+"[arg]; a[0] = x; return a[0];")
-                .parse().opto().typeCheck();
-            CodeGen loop = new CodeGen("var a = new "+type+"[arg]; "+
-                "for(int i=0; i<arg; i++) a[i] += i+0.25; return a[0]+a[arg-1];")
-                .parse().opto().typeCheck();
-            assertEquals("0.5",Eval2.eval(loop,1));
-            assertEquals("3.5",Eval2.eval(loop,4));
-
-            CodeGen rounded = new CodeGen("var a = new "+type+"[arg]; "+
-                "for(int i=0; i<arg; i++) a[i] = 16777216.0+i; return a[arg-1];")
-                .parse().opto().typeCheck();
-            assertEquals(type.equals("f32") ? "1.6777216E7" : "1.6777217E7",Eval2.eval(rounded,2));
-        }
-        CodeGen rounded = new CodeGen("var a = new f32[arg]; "+
-            "for(int i=0; i<arg; i++) a[i] = 16777217.0; return a[arg-1];")
-            .parse().opto().typeCheck();
-        assertEquals("1.6777216E7",Eval2.eval(rounded,2));
-    }
-
     @Test public void testNeverExitLoopDepth() {
         String[] sources = {
             "if(arg) while(1) {} return 7;",
@@ -204,7 +180,7 @@ return sq;
 """);
         code.parse().opto();
         assertEquals("Stop[ return { sq}; return (Parm_x(sq,int)*x); ]", code._stop.toString());
-        assertEquals("{ sq}", Eval2.eval(code, 3));
+        assertEquals("{ int -> int #1}", Eval2.eval(code, 3));
     }
 
     @Test
@@ -216,7 +192,7 @@ var sq = { int x ->
 };
 return sq(arg)+sq(3);
 """);
-        code.parse().opto();
+        code.parse().opto().typeCheck().GCM().localSched();
         assertEquals("Stop[ return (sq( 3)+sq( arg)); return (Parm_x(sq,int,3,arg)*x); ]", code._stop.toString());
         assertEquals("13", Eval2.eval(code, 2));
     }
@@ -255,7 +231,7 @@ var fcn = arg ? { int x -> x*x; } : { int x -> x+x; };
 return fcn(3);
 """);
         code.parse().opto();
-        assertEquals("Stop[ return Phi(Region,{ int -> int #1},{ int -> int #2})( 3); return (Parm_x($fun,int,3)*x); return (Parm_x($fun,int,3)*2); ]", code._stop.toString());
+        assertEquals("Stop[ return Phi(Region,{ int -> int #1},{ int -> int #2})( 3); return (Parm_x($fun,int,3)*x); return (Parm_x($fun,int,3)<<1); ]", code._stop.toString());
         assertEquals("6", Eval2.eval(code, 0));
         assertEquals("9", Eval2.eval(code, 1));
     }
@@ -264,7 +240,7 @@ return fcn(3);
     @Test
     public void testFcn5() {
         CodeGen code = new CodeGen("val fact = { int x -> x <= 1 ? 1 : x*fact(x-1); }; return fact(arg);");
-        code.parse().opto();
+        code.parse().opto().typeCheck();
         assertEquals("Stop[ return fact( arg); return Phi(Region,1,(Parm_x(fact,int,arg,(x-1))*fact( Sub))); ]", code._stop.toString());
         assertEquals( "1", Eval2.eval(code, 0));
         assertEquals( "1", Eval2.eval(code, 1));
@@ -319,7 +295,6 @@ for(;;) {
         assertEquals("3", Eval2.eval(code,  0));
     }
 
-
     @Test
     public void testFcn9() {
         CodeGen code = new CodeGen(
@@ -336,6 +311,31 @@ for(;;) {
         assertEquals(null, Eval2.eval(code,  0));
     }
 
+
+    @Test
+    public void testFcn10() {
+        CodeGen code = new CodeGen(
+"""
+struct Person {
+  int age;
+};
+
+val fcn = { !Person?[] !ps, int x ->
+  val tmp = ps[x];
+  if( ps[x] )
+    ps[x].age++;
+};
+
+var ps = new !Person?[2];
+ps[0] = new Person;
+ps[1] = new Person;
+fcn(ps,1);
+""");
+        code.parse().opto().typeCheck().GCM().localSched();
+        assertEquals("return 0;", code._stop.toString());
+        assertEquals("0", Eval2.eval(code,  0));
+    }
+
     // Function break
     @Test
     public void testErr1() {
diff --git a/src/test/java/com/seaofnodes/simple/Chapter19Test.java b/src/test/java/com/seaofnodes/simple/Chapter19Test.java
new file mode 100644
index 00000000..1abda81f
--- /dev/null
+++ b/src/test/java/com/seaofnodes/simple/Chapter19Test.java
@@ -0,0 +1,529 @@
+package com.seaofnodes.simple;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.*;
+
+
+import org.junit.Test;
+import static org.junit.Assert.*;
+import static org.junit.Assert.fail;
+import org.junit.Ignore;
+
+public class Chapter19Test {
+    @Test public void testPrintingFunctionLookup() {
+        var code = new CodeGen("return 0;").parse();
+        var tfp = TypeFunPtr.make((byte)2,TypeTuple.make(TypeInteger.constant(987654)),TypeInteger.constant(123456),1L<<30);
+        var con = new ConstantNode(tfp);
+        var call = new CallNode(null,code._start,con,con);
+        // Diagnostic lookup may construct/intern the return-erased linker key.
+        con.toString();
+        org.junit.Assert.assertNull(call.name());
+
+        var fun = new FunNode(null,tfp);
+        fun._name = "printerTarget";
+        fun.addDef(code._start);
+        code.link(fun);
+        var otherReturn = tfp.makeFrom(TypeInteger.constant(654321));
+        org.junit.Assert.assertSame(fun,code.link(otherReturn));
+        org.junit.Assert.assertTrue(con.toString().contains("printerTarget"));
+        assertEquals("printerTarget",call.name());
+    }
+
+
+    @Ignore
+    @Test
+    public void testJig() {
+        CodeGen code = new CodeGen("""
+return 0;
+""");
+        code.parse().opto().typeCheck();
+        assertEquals("return 0;", code._stop.toString());
+        assertEquals("0", Eval2.eval(code,  2));
+    }
+
+
+    @Test
+    public void testString() {
+        CodeGen code = new CodeGen(
+"""
+struct String {
+    u8[] !cs;
+    int _hashCode;
+};
+
+val equals = { !String !self, !String s ->
+    if( self == s ) return true;
+    if( self.cs# != s.cs# ) return false;
+    for( int i=0; i< self.cs#; i++ )
+        if( self.cs[i] != s.cs[i] )
+            return false;
+    return true;
+};
+
+val hashCode = { !String self ->
+    self._hashCode
+    ?  self._hashCode
+    : (self._hashCode = _hashCodeString(self));
+};
+
+val _hashCodeString = { !String self ->
+    int hash=0;
+    if( self.cs ) {
+        for( int i=0; i< self.cs#; i++ )
+            hash = hash*31 + self.cs[i];
+    }
+    if( !hash ) hash = 123456789;
+    return hash;
+};
+
+!String !s = new String { cs = new u8[17]; };
+s.cs[0] =  67; // C
+s.cs[1] = 108; // l
+hashCode(s);""");
+        code.parse().opto().typeCheck().GCM().localSched();
+        assertEquals("Stop[ return Phi(Region,123456789,Phi(Loop,0,(.[]+((Phi_hash<<5)-Phi_hash)))); return Phi(Region,1,0,0,1); ]", code._stop.toString());
+        assertEquals("-2449306563677080489", Eval2.eval(code,  2));
+    }
+
+    @Test
+    public void testBasic0() {
+        CodeGen code = new CodeGen("return 0;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return 0;", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic1() {
+        CodeGen code = new CodeGen("return arg+1;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (inc,arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic2() {
+        CodeGen code = new CodeGen("return -17;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return -17;", code._stop.toString());
+    }
+
+
+    @Test
+    public void testBasic3() {
+        CodeGen code = new CodeGen("return arg==1;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (set==,(cmp,arg));", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic4() {
+        CodeGen code = new CodeGen("return arg<<1;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (shli,arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic5() {
+        CodeGen code = new CodeGen("return arg >> 1;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (sari,arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic6() {
+        CodeGen code = new CodeGen("return arg >>> 1;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (shri,arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic7() {
+        CodeGen code = new CodeGen("return arg / 2;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (div,arg,2);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic8() {
+        CodeGen code = new CodeGen("return arg * 6;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (muli,arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic9() {
+        CodeGen code = new CodeGen("return arg & 2;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (andi,arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic10() {
+        CodeGen code = new CodeGen("return arg | 2;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (ori,arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic11() {
+        CodeGen code = new CodeGen("return arg ^ 2;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (xori,arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic12() {
+        CodeGen code = new CodeGen("return arg + 2.0;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (addf,(i2f8,arg),2.0f);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic13() {
+        CodeGen code = new CodeGen("return arg - 2.0;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (subf,(i2f8,arg),2.0f);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic14() {
+        CodeGen code = new CodeGen("return arg * 2.0;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (mulf,(i2f8,arg),2.0f);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic15() {
+        CodeGen code = new CodeGen("return arg / 2.0;").parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (divf,(i2f8,arg),2.0f);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic16() {
+        CodeGen code = new CodeGen(
+"""
+int arg1 =  arg + 1;
+return arg1 / arg;""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (div,(inc,arg),arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic17() {
+        CodeGen code = new CodeGen(
+"""
+int arg1 =  arg + 1;
+return arg1 * arg;
+""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (mul,(inc,arg),arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic18() {
+        CodeGen code = new CodeGen(
+                """
+                int arg1 =  arg + 1;
+                return arg1 << arg;
+                """);
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (shl,(inc,arg),arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic19() {
+        CodeGen code = new CodeGen(
+                """
+                int arg1 =  arg + 1;
+                return arg1 >> arg;
+                """);
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (sar,(inc,arg),arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testBasic20() {
+        CodeGen code = new CodeGen(
+                """
+                int arg1 =  arg + 1;
+                return arg1 >>> arg;
+                """);
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (shr,(inc,arg),arg);", code._stop.toString());
+    }
+
+    @Test
+    public void testToFloat() {
+        CodeGen code = new CodeGen("""
+                int a = arg;
+                return a + 2.0;
+                """
+        ).parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (addf,(i2f8,arg),2.0f);", code._stop.toString());
+    }
+
+    @Test
+    public void testIfStmt() {
+        CodeGen code = new CodeGen(
+"""
+int a = 1;
+if (arg == 1)
+    a = arg+2;
+else {
+    a = arg-3;
+}
+return a;""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return Phi(Region,(addi,arg),(addi,arg));", code.print());
+    }
+
+    @Test
+    public void testIfMerge2() {
+        CodeGen code = new CodeGen(
+"""
+int a=arg+1;
+int b=arg+2;
+if( arg==1 )
+    b=b+a;
+else
+    a=b+1;
+return a+b;""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (add,(add,Phi(Region,(shli,arg),arg),arg),Phi(Region,4,5));", code.print());
+    }
+
+    @Test
+    public void testLoop() {
+        CodeGen code = new CodeGen(
+"""
+int sum=0;
+for( int i=0; i<arg; i++ )
+    sum += i;
+return sum;""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return Phi(Loop,0,(add,Phi_sum,Phi(Loop,0,(inc,Phi_i))));", code.print());
+    }
+
+    @Test
+    public void testAlloc1() {
+        CodeGen code = new CodeGen(
+"""
+struct S { int a; !S? !c; };
+return new S;""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return S;", code.print());
+    }
+
+    @Test
+    public void testLea1() {
+        CodeGen code = new CodeGen("int x = arg/3; return arg+x+7;");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2",  "SystemV").GCM().localSched();
+        assertEquals("return (lea,arg,(div,arg,3));", code.print());
+    }
+
+    @Test
+    public void testLea2() {
+        CodeGen code = new CodeGen("int x = arg/3; return arg+x*4+7;");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return (lea,arg,(div,arg,3));", code.print());
+    }
+
+    @Test
+    public void testLea3() {
+        CodeGen code = new CodeGen("int x = arg/3; return x*4+arg;");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2",  "SystemV").GCM().localSched();
+        assertEquals("return (lea,arg,(div,arg,3));", code.print());
+    }
+
+    @Test
+    public void testAlloc2() {
+        CodeGen code = new CodeGen("int[] !xs = new int[3]; xs[arg]=1; return xs[arg&1];");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return .[];", code.print());
+    }
+
+    @Test
+    public void testAlloc3() {
+        CodeGen code = new CodeGen("int[] !xs = new int[3]; xs[arg]=1; return xs[arg&1]+3;");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return .[];", code.print());
+    }
+
+    @Test
+    public void testArray1() {
+        CodeGen code = new CodeGen(
+"""
+int[] !ary = new int[arg];
+// Fill [0,1,2,3,4,...]
+for( int i=0; i<ary#; i++ )
+    ary[i] = i;
+// Fill [0,1,3,6,10,...]
+for( int i=0; i<ary#-1; i++ )
+    ary[i+1] += ary[i];
+return ary[1] * 1000 + ary[3]; // 1 * 1000 + 6
+""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return .[];", code.print());
+    }
+
+    @Test
+    public void testArray2() {
+        CodeGen code = new CodeGen(
+"""
+flt[] !A = new flt[arg], !B = new flt[arg];
+// Fill [0,1,2,3,4,...]
+for( int i=0; i<A#; i++ )
+    A[i] = i;
+for( int i=0; i<A#; i++ )
+    B[i] += A[i];
+""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return 0;", code.print());
+    }
+
+    @Test
+    public void testArray3() {
+        CodeGen code = new CodeGen(
+"""
+byte[] !A = new byte[arg];
+for( int i=0; i<A#; i++ )
+    A[i]++;
+return A[1];
+""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return .[];", code.print());
+    }
+
+    @Test
+    public void testNewton() {
+        CodeGen code = new CodeGen(
+"""
+// Newtons approximation to the square root
+val sqrt = { flt x ->
+    flt guess = x;
+    while( 1 ) {
+        flt next = (x/guess + guess)/2;
+        if( next == guess ) return guess;
+        guess = next;
+    }
+};
+flt farg = arg;
+return sqrt(farg);
+""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return Phi(Loop,(i2f8,arg),(divf,(addf,(divf,i2f8,Phi_guess),Phi_guess),2.0f));", code.print());
+    };
+
+
+    @Test
+    public void sieveOfEratosthenes() {
+        CodeGen code = new CodeGen(
+"""
+var ary = new bool[arg], primes = new int[arg];
+var nprimes=0, p=0;
+// Find primes while p^2 < arg
+for( p=2; p*p < arg; p++ ) {
+    // skip marked non-primes
+    while( ary[p] ) p++;
+    // p is now a prime
+    primes[nprimes++] = p;
+    // Mark out the rest non-primes
+    for( int i = p + p; i < ary#; i += p )
+        ary[i] = true;
+}
+// Now just collect the remaining primes, no more marking
+for( ; p < arg; p++ )
+    if( !ary[p] )
+        primes[nprimes++] = p;
+// Copy/shrink the result array
+var !rez = new int[nprimes];
+for( int j=0; j<nprimes; j++ )
+    rez[j] = primes[j];
+return rez;
+""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("return [int];", code.print());
+        //assertEquals("int[ 2,3,5,7,11,13,17,19]",Eval2.eval(code, 20));
+    }
+
+
+    @Test
+    public void testFcn1() {
+        CodeGen code = new CodeGen(
+"""
+val fcn = arg ? { int x -> x*x; } : { int x -> x+x; };
+return fcn(2)*10 + fcn(3);
+""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("Stop[ return (add,Phi(Region,{ int -> int #1},{ int -> int #2})( 3),(muli,Phi_( 2))); return (mul,Parm_x($fun,int,3,2),x); return (shli,Parm_x($fun,int,3,2)); ]", code.print());
+    }
+
+    @Test
+    public void testFcn2() {
+        CodeGen code = new CodeGen(
+"""
+val sq = { int x -> x*x; };
+return sq(arg) + sq(3);
+""");
+        code.parse().opto().typeCheck().instSelect("x86_64_v2", "SystemV").GCM().localSched();
+        assertEquals("Stop[ return (add,sq(),sq()); return (mul,Parm_x(sq,int,3,arg),x); ]", code.print());
+    }
+
+    @Test public void testSelectedMemory() {
+        for( String cpu : new String[]{"x86_64_v2","riscv"} )
+            for( String src : new String[]{Chapter10Test.NESTED_MEMORY,Chapter16Test.CONSTRUCTOR_MEMORY,
+                                          Chapter18Test.CALL_MEMORY,Chapter18Test.RECURSIVE_MEMORY} ) {
+                var code = new CodeGen(src).parse().opto().typeCheck();
+                var aliases = memoryPhis(code._stop);
+                code.instSelect(cpu,"SystemV");
+                assertEquals(aliases,memoryPhis(code._stop));
+                code.GCM().localSched();
+                code._stop.walk(n -> {
+                    if( !(n instanceof CFGNode) && !(n instanceof ProjNode) )
+                        assertTrue(n.in(0) instanceof CFGNode);
+                    if( n instanceof NewNode nn ) {
+                        assertEquals(2,((TypeTuple)nn._type)._types.length);
+                        assertTrue(nn.mem() instanceof MemMergeNode);
+                        assertNull(nn.mem().in(1)); // Partial allocation input.
+                        MachNode mach = (MachNode)nn;
+                        assertNull(mach.regmap(1));
+                        assertNotNull(mach.regmap(2));
+                        assertNotNull(mach.outregmap(0));
+                        assertNull(mach.outregmap(1));
+                    }
+                    if( n instanceof CallNode call ) {
+                        assertEquals(4,call.nIns()); // ctrl, memory, two args; direct target is embedded.
+                    }
+                    return null;
+                });
+            }
+    }
+
+    private static java.util.ArrayList<String> memoryPhis(Node stop) {
+        var phis = new java.util.ArrayList<String>();
+        // Count only definitions reachable from Stop, as instruction selection does.
+        // A dead Phi cycle can still appear through the reverse use edges.
+        var seen = new java.util.BitSet();
+        var work = new java.util.ArrayList<Node>();
+        work.add(stop);
+        for( int i=0; i<work.size(); i++ ) {
+            Node n = work.get(i);
+            if( n==null || seen.get(n._nid) ) continue;
+            seen.set(n._nid);
+            for( Node def : n._inputs ) work.add(def);
+            if( n instanceof MemPhiNode phi ) phis.add("alias:"+phi._alias);
+            if( n instanceof BulkMemPhiNode phi ) phis.add("bulk:"+phi._aliases);
+            assertFalse(n instanceof PhiNode && n.isMem() &&
+                !(n instanceof MemPhiNode) && !(n instanceof BulkMemPhiNode) && !(n instanceof ParmNode));
+        }
+        java.util.Collections.sort(phis);
+        return phis;
+    }
+
+    @Test public void testFoldedReadBeforeWrites() {
+        var code = new CodeGen("""
+            struct S { int x; };
+            !S !a = new S { x=11; }; !S !b = new S { x=22; };
+            !S !p = a; if( arg ) p = b;
+            int before = p.x + arg;
+            a.x=33; b.x=44;
+            return before;
+            """).parse().opto().typeCheck().instSelect("x86_64_v2","SystemV").GCM().localSched();
+        var read = (MemOpNode)code._stop.walk(n ->
+            n instanceof com.seaofnodes.simple.node.cpus.x86_64_v2.AddMemX86 ? n : null);
+        assertNotNull(read);
+        int writes = 0;
+        for( Node use : read.antiDeps() )
+            if( use instanceof MemOpNode st && st.isMem() ) {
+                assertSame(read.cfg0(),st.cfg0());
+                assertTrue(st._inputs.find(read)>=0);
+                assertTrue(read.cfg0()._outputs.find(read)<st.cfg0()._outputs.find(st));
+                assertNull(((MachNode)st).regmap(st._inputs.find(read)));
+                writes++;
+            }
+        assertEquals(1,writes); // The next Store follows this first clobber through memory.
+    }
+}
diff --git a/src/test/java/com/seaofnodes/simple/Eval2.java b/src/test/java/com/seaofnodes/simple/Eval2.java
index 3f337e86..46251cef 100644
--- a/src/test/java/com/seaofnodes/simple/Eval2.java
+++ b/src/test/java/com/seaofnodes/simple/Eval2.java
@@ -179,7 +179,7 @@ public abstract class Eval2 {
         int path = r._inputs.find( prior );
         // Parameters read from prior frame, Phis from local frame
         Frame frame = (r instanceof FunNode ? F._prior : F);
-        boolean isMain = r instanceof FunNode fun && fun.sig().isa(TypeFunPtr.MAIN);
+        boolean isMain = r instanceof FunNode fun && fun.sig().isa(CodeGen.CODE._main);
 
         // Parallel assign Phis.  First parallel read and cache
         int i;
@@ -349,7 +349,7 @@ public abstract class Eval2 {
         int num = type._fields.length;
         Object[] ptr = new Object[num];
         for( int i=0; i<num; i++ )
-            ptr[i] = val(alloc.in(3+i));
+            ptr[i] = con(type._fields[i]._type.makeZero());
         return ptr;
     }
 
@@ -365,6 +365,8 @@ public abstract class Eval2 {
     }
 
     private static Object store( StoreNode st ) {
+        if( st._name.equals("#") )
+            return "$mem";      // Eval stores the length in the java object[], no need to set it now
         TypeMemPtr tmp = (TypeMemPtr)st.ptr()._type;
         Object[] fs = (Object[])val(st.ptr());
         int idx = tmp._obj.isAry()
diff --git a/src/test/java/com/seaofnodes/simple/FuzzerWrap.java b/src/test/java/com/seaofnodes/simple/FuzzerWrap.java
index 143828e6..b022bec9 100644
--- a/src/test/java/com/seaofnodes/simple/FuzzerWrap.java
+++ b/src/test/java/com/seaofnodes/simple/FuzzerWrap.java
@@ -7,10 +7,9 @@ import org.junit.Test;
 import static org.junit.Assert.assertTrue;
 
 /**
- * Normal tests run only this chapter's fixed regression seeds. Open failures
- * and exploratory fuzzing are opt-in: run their methods directly in the IDE,
- * or temporarily remove the relevant Ignore annotation when investigating.
- * Seeds belong to this chapter's generator; do not copy them between chapters.
+ * Normal tests run chapter-local regression seeds. Open failures and exploratory
+ * fuzzing are opt-in (run directly in the IDE or temporarily remove Ignore).
+ * Seeds depend on this chapter's generator; do not copy them between chapters.
  */
 public class FuzzerWrap {
 
diff --git a/src/test/java/com/seaofnodes/simple/Main.java b/src/test/java/com/seaofnodes/simple/Main.java
new file mode 100644
index 00000000..523bd306
--- /dev/null
+++ b/src/test/java/com/seaofnodes/simple/Main.java
@@ -0,0 +1,17 @@
+package com.seaofnodes.simple;
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+public class Main {
+    // Compile and run a simple program
+    public static void main( String[] args ) throws Exception {
+        // First arg is file, 2nd+ args are program args
+        String src = Files.readString(Path.of(args[0]));
+        int arg = Integer.valueOf(args[1]);
+        CodeGen code = new CodeGen(src);
+        code.parse().opto().typeCheck().GCM().localSched();
+        System.out.println(code._stop);
+        System.out.println(Eval2.eval(code,arg,100000));
+    }
+}
diff --git a/src/test/java/com/seaofnodes/simple/evaluator/Evaluator.java b/src/test/java/com/seaofnodes/simple/evaluator/Evaluator.java
index 7dbc551e..cb98971b 100644
--- a/src/test/java/com/seaofnodes/simple/evaluator/Evaluator.java
+++ b/src/test/java/com/seaofnodes/simple/evaluator/Evaluator.java
@@ -199,14 +199,17 @@ public class Evaluator {
                 assert elem instanceof TypeMemPtr;
             }
             // Length value
-            body[0] = vall(alloc.in(3));
+            body[0] = n;
         } else {
             body = new Object[num = type._fields.length];
-            for (int i=0; i<num; i++)
-                body[i] = val(alloc.in(3+i));
+            for( int i=0; i<num; i++ )
+                body[i] = switch( alloc._ptr._obj._fields[i]._type ) {
+                case TypeInteger ti -> 0L;
+                case TypeFloat tf -> 0D;
+                default -> null;
+                };
         }
         return new Object[]{new Obj(type,body),null};
-
     }
 
     private Object load(LoadNode load) {
@@ -341,7 +344,7 @@ public class Evaluator {
                 assert block != null;
                 for (; i < block.nodes().length; i++) {
                     if (!(block.nodes()[i] instanceof PhiNode phi)) break;
-                    var val = region instanceof FunNode fun && "main".equals(fun.sig()._name) && ((ParmNode)phi)._idx==2 && exit==1
+                    var val = region instanceof FunNode fun && "main".equals(fun._name) && ((ParmNode)phi)._idx==2 && exit==1
                             ? parameter
                             : val(phi.in(exit));
                     phiCache.add(val);
diff --git a/src/test/java/com/seaofnodes/simple/evaluator/Scheduler.java b/src/test/java/com/seaofnodes/simple/evaluator/Scheduler.java
index 52d8f3e3..4bfa7628 100644
--- a/src/test/java/com/seaofnodes/simple/evaluator/Scheduler.java
+++ b/src/test/java/com/seaofnodes/simple/evaluator/Scheduler.java
@@ -508,7 +508,7 @@ public class Scheduler {
     private static CFGNode findSingleCFGOut(Node node) {
         if (node instanceof StartNode) {
             for(var n:node._outputs)
-                if (n instanceof FunNode fun && "main".equals(fun.sig()._name) )
+                if (n instanceof FunNode fun && "main".equals(fun._name) )
                    return fun;
             return null;
         }
diff --git a/src/test/java/com/seaofnodes/simple/fuzzer/Fuzzer.java b/src/test/java/com/seaofnodes/simple/fuzzer/Fuzzer.java
index a5634e82..851380cf 100644
--- a/src/test/java/com/seaofnodes/simple/fuzzer/Fuzzer.java
+++ b/src/test/java/com/seaofnodes/simple/fuzzer/Fuzzer.java
@@ -126,17 +126,16 @@ public class Fuzzer {
             var code = new CodeGen(sb.toString());
 
             code.parse();
-            int parse_peeps= Node.ITER_CNT;
-            int parse_nops = Node.ITER_NOP_CNT;
+            int nids = code.UID();
+            if( nids <= max_nids ) return max_nids; // Smaller, looking for trends as we grow
+            int parse_peeps= code._iter_cnt;
+            int parse_nops = code._iter_nop_cnt;
             double parse_nop_ratio = (double)parse_nops/parse_peeps;
-            int nids = Node.UID();
-            if( nids <= max_nids ) return max_nids;
-
             double parse_peeps_per_node = (double)parse_peeps/nids;
 
             code.opto();
-            int iter_peeps= Node.ITER_CNT;
-            int iter_nops = Node.ITER_NOP_CNT;
+            int iter_peeps= code._iter_cnt;
+            int iter_nops = code._iter_nop_cnt;
             double iter_nop_ratio = (double)iter_nops/iter_peeps;
             double iter_peeps_per_node = (double)iter_peeps/nids;
 
@@ -173,7 +172,7 @@ public class Fuzzer {
         return exceptions.isEmpty();
     }
 
-    /** Run a fixed seed without reducing or swallowing failures. */
+    /** Run a fixed chapter-local seed without reducing or swallowing failures. */
     public void fuzzPeepsRegression(long seed) {
         var rand = new Random(seed);
         var sb = new StringBuilder();
diff --git a/src/test/java/com/seaofnodes/simple/fuzzer/FuzzerUtils.java b/src/test/java/com/seaofnodes/simple/fuzzer/FuzzerUtils.java
index 4509c6fc..5c89a485 100644
--- a/src/test/java/com/seaofnodes/simple/fuzzer/FuzzerUtils.java
+++ b/src/test/java/com/seaofnodes/simple/fuzzer/FuzzerUtils.java
@@ -4,6 +4,7 @@ import com.seaofnodes.simple.CodeGen;
 import com.seaofnodes.simple.IterPeeps;
 import com.seaofnodes.simple.node.Node;
 import com.seaofnodes.simple.node.StopNode;
+import com.seaofnodes.simple.type.TypeInteger;
 import java.io.OutputStream;
 import java.io.PrintStream;
 import java.lang.invoke.MethodHandle;
@@ -46,34 +47,11 @@ class FuzzerUtils {
         return new RuntimeException(e);
     }
 
-    /**
-     * Copy of Node.WVISIST
-     * Used to clear as exceptions might happen in the walk and left this bitset not cleared
-     */
-    private static final BitSet NodeWalkVisit;
-    private static final java.util.Random WorkRandom;
-
-    /**
-     * Write access to Iterate.MID_ASSERT
-     * Exception could happen mid assert and left this at true. Used to reset to false prior to parsing.
-     */
-    private static final MethodHandle set_MID_ASSERT;
-
     /**
      * Some problems might trigger debug output. Suppress this output with a null print stream during fuzzing.
      */
     public static final PrintStream NULL_PRINT_STREAM = new PrintStream(OutputStream.nullOutputStream());
 
-    static {
-        try {
-            NodeWalkVisit = getFieldValue(Node.class, "WVISIT");
-            WorkRandom = getFieldValue(getFieldValue(IterPeeps.class, "WORK"), "_R");
-            set_MID_ASSERT = MethodHandles.lookup().unreflectSetter(getField( IterPeeps.class, "MID_ASSERT"));
-        } catch (Exception e) {
-            throw new ExceptionInInitializerError(e);
-        }
-    }
-
     /**
      * Check that the messages are similar.
      */
@@ -122,17 +100,9 @@ class FuzzerUtils {
         try {
             System.setErr(NULL_PRINT_STREAM);
             System.setOut(NULL_PRINT_STREAM);
-            try {
-                set_MID_ASSERT.invokeExact(false);
-            } catch (Throwable e) {
-                throw rethrow(e);
-            }
-            var code = new CodeGen(script);
-            code.parse();
-            WorkRandom.setSeed(workListSeed);
-            return code.opto().typeCheck().GCM().localSched();
+            var code = new CodeGen(script, TypeInteger.BOT, workListSeed);
+            return code.parse().opto().typeCheck().GCM().localSched();
         } finally {
-            NodeWalkVisit.clear();
             System.setErr(err);
             System.setOut(out);
         }
diff --git a/src/test/java/com/seaofnodes/simple/fuzzer/ScriptGenerator.java b/src/test/java/com/seaofnodes/simple/fuzzer/ScriptGenerator.java
index d061a656..167a5b24 100644
--- a/src/test/java/com/seaofnodes/simple/fuzzer/ScriptGenerator.java
+++ b/src/test/java/com/seaofnodes/simple/fuzzer/ScriptGenerator.java
@@ -3,12 +3,13 @@ package com.seaofnodes.simple.fuzzer;
 import com.seaofnodes.simple.Parser;
 import com.seaofnodes.simple.node.ScopeNode;
 import com.seaofnodes.simple.type.TypeInteger;
-
 import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Random;
 import java.util.function.Predicate;
+import static com.seaofnodes.simple.Parser.KEYWORDS;
+
 
 /**
  * Generate a pseudo random script.
@@ -34,18 +35,6 @@ public class ScriptGenerator {
      * Valid characters for identifiers. The last 10 are not valid for the first character.
      */
     private static final String VAR_CHARS = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_0123456789";
-    /**
-     * List of keywords not valid for identifiers.
-     */
-    private static final HashSet<String> KEYWORDS;
-
-    static {
-        try {
-            KEYWORDS = FuzzerUtils.getFieldValue(new Parser(""), "KEYWORDS");
-        } catch (Throwable e) {
-            throw new ExceptionInInitializerError(e);
-        }
-    }
 
     /**
      * Flag for a statement that it does not pass on control flow to the next statement.
@@ -108,7 +97,6 @@ public class ScriptGenerator {
     private static final List<TypeInt> INTTYPES = new ArrayList<>();
 
     static {
-        new Parser("", TypeInteger.BOT);
         for( var e : Parser.defaultTypes().entrySet() ) {
             if( e.getValue() instanceof TypeInteger ) {
                 INTTYPES.add(new TypeInt(e.getKey()));
diff --git a/src/test/java/com/seaofnodes/simple/progs/fcn.smp b/src/test/java/com/seaofnodes/simple/progs/fcn.smp
new file mode 100644
index 00000000..43d398b3
--- /dev/null
+++ b/src/test/java/com/seaofnodes/simple/progs/fcn.smp
@@ -0,0 +1,15 @@
+
+struct Person {
+  int age;
+};
+
+val fcn = { !Person?[] ps, int x ->
+  val tmp = ps[x];
+  if( ps[x] )
+    ps[x].age++;
+};
+
+!Person?[] !ps = new !Person?[2];
+ps[0] = new Person;
+ps[1] = new Person;
+fcn(ps,1);
diff --git a/src/test/java/com/seaofnodes/simple/progs/fcn2.smp b/src/test/java/com/seaofnodes/simple/progs/fcn2.smp
new file mode 100644
index 00000000..049132d9
--- /dev/null
+++ b/src/test/java/com/seaofnodes/simple/progs/fcn2.smp
@@ -0,0 +1,5 @@
+
+val fcn = (arg&1)
+    ? { int x -> x*x; }
+    : { int x -> x+x; };
+fcn(arg);
diff --git a/src/test/java/com/seaofnodes/simple/progs/fcn3.smp b/src/test/java/com/seaofnodes/simple/progs/fcn3.smp
new file mode 100644
index 00000000..55b74455
--- /dev/null
+++ b/src/test/java/com/seaofnodes/simple/progs/fcn3.smp
@@ -0,0 +1,42 @@
+
+//val fact = { int n -> n <= 1 ? 1 : fact(n-1)*n; }
+struct LL { !LL? !next; int payload; };
+
+
+struct String {
+
+    val _hashCodeString = { ->
+        int hash=0;
+        for( int i=0; i< cs#; i++ )
+            hash = hash*31 + cs[i];
+        if( !hash ) hash = 123456789;
+        return hash;
+    };
+
+    val equals = { !String s ->
+        if( self == s ) return true;
+        if( cs# != s.cs# ) return false;
+        for( int i=0; i< #; i++ )
+            if( [i] != s.cs[i] )
+                return false;
+        return true;
+    };
+
+    int _hashCode = hash();
+    u8[] cs;
+};
+
+
+
+val hashCode= { !String self ->
+    int hash = self._hashCode
+    ? self._hashCode
+    : self._hashCode = _hashCodeString(self);
+    return hash;
+};
+
+
+String s = new String { cs = new u8[17]; };
+s.cs[0] =  67; // C
+s.cs[1] = 108; // l
+hashCode(s);
diff --git a/src/test/java/com/seaofnodes/simple/progs/sieve.smp b/src/test/java/com/seaofnodes/simple/progs/sieve.smp
new file mode 100644
index 00000000..0788e6c5
--- /dev/null
+++ b/src/test/java/com/seaofnodes/simple/progs/sieve.smp
@@ -0,0 +1,32 @@
+
+int[] !ary = new int[arg], !primes = new int[arg];
+int nprimes = 0, p=2;
+// Find primes while p^2 < arg
+while( p*p < arg ) {
+    // skip marked non-primes
+    while( ary[p]==1 ) p = p + 1;
+    // p is now a prime
+    primes[nprimes] = p;  nprimes = nprimes + 1;
+    // Mark out the rest non-primes
+    int i = p + p;
+    while( i < ary# ) {
+        ary[i] = 1;
+        i = i + p;
+    }
+    p = p + 1;
+}
+// Now just collect the remaining primes, no more marking
+while( p < arg ) {
+    if( ary[p] == 0 ) {
+        primes[nprimes] = p;  nprimes = nprimes + 1;
+    }
+    p = p + 1;
+}
+// Copy/shrink the result array
+int[] !rez = new int[nprimes];
+int j = 0;
+while( j < nprimes ) {
+    rez[j] = primes[j];
+    j = j + 1;
+}
+return rez;
-- 
cgit v1.2.3