Add a sys.io.p

Remove dead sys calls
Saves many test cases tracking count of returned functions.
Move call unlinking even early.
Print extern calls better.
Fix call anti-dep register bug.
Fix TFP hash punning.
Fix ParmNode hash punning.
Sys calls get a sane name.
Stop filters sys calls.

7 files changed, 28 insertions, 24 deletions

diff --git a/chapter22/src/test/java/com/seaofnodes/simple/Chapter01Test.java b/chapter22/src/test/java/com/seaofnodes/simple/Chapter01Test.java
index cddbdfcf..ac9adacc 100644
--- a/chapter22/src/test/java/com/seaofnodes/simple/Chapter01Test.java
+++ b/chapter22/src/test/java/com/seaofnodes/simple/Chapter01Test.java
@@ -25,9 +25,9 @@ public class Chapter01Test {
     public void testZero() {
         CodeGen code = new CodeGen("return 0;");
         code.parse();
-        for( Node use : code._start._outputs )
-            if( use instanceof ConstantNode con && con._type instanceof TypeInteger )
-                assertEquals(TypeInteger.constant(0),con._type);
+        Node use = code.expr();
+        if( use instanceof ConstantNode con && con._type instanceof TypeInteger )
+            assertEquals(TypeInteger.constant(0),con._type);
     }
 
     @Test
diff --git a/chapter22/src/test/java/com/seaofnodes/simple/Chapter18Test.java b/chapter22/src/test/java/com/seaofnodes/simple/Chapter18Test.java
index 9c8ad66c..16634580 100644
--- a/chapter22/src/test/java/com/seaofnodes/simple/Chapter18Test.java
+++ b/chapter22/src/test/java/com/seaofnodes/simple/Chapter18Test.java
@@ -78,7 +78,7 @@ var sq = { int x ->
 return sq(arg)+sq(3);
 """);
         code.driver(Phase.LocalSched);
-        assertEquals("Stop[ return (#2+#2); return (Parm_x(sq,int)*x); ]", code._stop.toString());
+        assertEquals("Stop[ return (Parm_x(sq,int)*x); return (#2+#2); ]", code._stop.toString());
         assertEquals("13", Eval2.eval(code, 2));
     }
 
@@ -116,7 +116,7 @@ var fcn = arg ? { int x -> x*x; } : { int x -> x+x; };
 return fcn(3);
 """);
         code.parse().opto();
-        assertEquals("Stop[ return #2; return (Parm_x($fun1,int,3)*x); return (Parm_x($fun2,int,3)<<1); ]", code._stop.toString());
+        assertEquals("Stop[ return (Parm_x($fun2,int,3)<<1); return #2; return (Parm_x($fun1,int,3)*x); ]", code._stop.toString());
         assertEquals("6", Eval2.eval(code, 0));
         assertEquals("9", Eval2.eval(code, 1));
     }
@@ -126,7 +126,7 @@ return fcn(3);
     public void testFcn5() {
         CodeGen code = new CodeGen("val fact = { int x -> x <= 1 ? 1 : x*fact(x-1); }; return fact(arg);");
         code.parse().opto().typeCheck();
-        assertEquals("Stop[ return #2; return Phi(Region,1,(Parm_x(fact,int,arg,(x-1))*#2)); ]", code._stop.toString());
+        assertEquals("Stop[ return Phi(Region,1,(Parm_x(fact,int,arg,(x-1))*#2)); return #2; ]", code._stop.toString());
         assertEquals( "1", Eval2.eval(code, 0));
         assertEquals( "1", Eval2.eval(code, 1));
         assertEquals( "2", Eval2.eval(code, 2));
@@ -158,7 +158,7 @@ val g = {->2;};
 return 2;
 """);
         code.parse().opto().typeCheck().GCM();
-        assertEquals("Stop[ return 1; return 1; return 2; ]", code._stop.toString());
+        assertEquals("Stop[ return 2; return 1; return 1; ]", code._stop.toString());
         assertEquals("1", Eval2.eval(code,  0));
     }
 
@@ -176,7 +176,7 @@ for(;;) {
 }
 """);
         code.driver(Phase.LocalSched);
-        assertEquals("Stop[ return #2; return Parm_i(x,int); ]", code._stop.toString());
+        assertEquals("Stop[ return Parm_i(x,int); return #2; ]", code._stop.toString());
         assertEquals("3", Eval2.eval(code,  0));
     }
 
@@ -348,7 +348,7 @@ if (i2i) return i2i(arg);
 return f2f(o)(1);
 """);
         code.driver(Phase.LocalSched);
-        assertEquals("Stop[ return Phi(Region,#2,#2); return Parm_i(o,int); ]", code._stop.toString());
+        assertEquals("Stop[ return Parm_i(i2i.o,int); return Phi(Region,#2,#2); ]", code._stop.toString());
         assertEquals("1", Eval2.eval(code,  2));
     }
 
diff --git a/chapter22/src/test/java/com/seaofnodes/simple/Chapter19Test.java b/chapter22/src/test/java/com/seaofnodes/simple/Chapter19Test.java
index f06d8a6a..c6a701a4 100644
--- a/chapter22/src/test/java/com/seaofnodes/simple/Chapter19Test.java
+++ b/chapter22/src/test/java/com/seaofnodes/simple/Chapter19Test.java
@@ -25,7 +25,7 @@ return 0;
     public void testString() throws IOException {
         String src = Files.readString(Path.of("src/test/java/com/seaofnodes/simple/progs/stringHash.smp"));
         CodeGen code = new CodeGen(src).parse().opto().typeCheck().GCM().localSched();
-        assertEquals("Stop[ return Phi(Region,._hashCode,Phi(Region,123456789,Phi(Loop,0,(.[]+((Phi_hash<<5)-Phi_hash))))); return Phi(Region,1,0,0,1); ]", code._stop.toString());
+        assertEquals("Stop[ return Phi(Region,1,0,0,1); return Phi(Region,._hashCode,Phi(Region,123456789,Phi(Loop,0,(.[]+((Phi_hash<<5)-Phi_hash))))); ]", code._stop.toString());
         //assertEquals("-4898613127354160978", Eval2.eval(code,  2));
     }
 
@@ -316,7 +316,7 @@ val fcn = arg ? { int x -> x*x; } : { int x -> x+x; };
 return fcn(2)*10 + fcn(3);
 """);
         code.driver(Phase.LocalSched,"x86_64_v2", "SystemV");
-        assertEquals("Stop[ return (add,#2,(muli,#2)); return (mul,Parm_x($fun1,int),x); return (shli,Parm_x($fun2,int)); ]", code.print());
+        assertEquals("Stop[ return (shli,Parm_x($fun2,int)); return (add,#2,(muli,#2)); return (mul,Parm_x($fun1,int),x); ]", code.print());
     }
 
     @Test
@@ -327,6 +327,6 @@ val sq = { int x -> x*x; };
 return sq(arg) + sq(3);
 """);
         code.driver(Phase.LocalSched,"x86_64_v2", "SystemV");
-        assertEquals("Stop[ return (add,#2,#2); return (mul,Parm_x(sq,int),x); ]", code.print());
+        assertEquals("Stop[ return (mul,Parm_x(sq,int),x); return (add,#2,#2); ]", code.print());
     }
 }
diff --git a/chapter22/src/test/java/com/seaofnodes/simple/Chapter20Test.java b/chapter22/src/test/java/com/seaofnodes/simple/Chapter20Test.java
index f0b31065..4c4ac4e4 100644
--- a/chapter22/src/test/java/com/seaofnodes/simple/Chapter20Test.java
+++ b/chapter22/src/test/java/com/seaofnodes/simple/Chapter20Test.java
@@ -104,7 +104,7 @@ return sqrt(arg) + sqrt(cast_int);
         String src = Files.readString(Path.of("src/test/java/com/seaofnodes/simple/progs/stringHash.smp"));
         testCPU(src,"x86_64_v2", "SystemV", 9,null);
         testCPU(src,"riscv"    , "SystemV", 5,null);
-        testCPU(src,"arm"      , "SystemV", 6,null);
+        testCPU(src,"arm"      , "SystemV", 3,null);
     }
 
     @Test
diff --git a/chapter22/src/test/java/com/seaofnodes/simple/Chapter21Test.java b/chapter22/src/test/java/com/seaofnodes/simple/Chapter21Test.java
index 96e6c5ff..c6e0a3bd 100644
--- a/chapter22/src/test/java/com/seaofnodes/simple/Chapter21Test.java
+++ b/chapter22/src/test/java/com/seaofnodes/simple/Chapter21Test.java
@@ -65,7 +65,7 @@ public class Chapter21Test {
         String src = Files.readString(Path.of("src/test/java/com/seaofnodes/simple/progs/stringHash.smp"));
         testCPU(src,"x86_64_v2", "SystemV", 9,null);
         testCPU(src,"riscv"    , "SystemV", 5,null);
-        testCPU(src,"arm"      , "SystemV", 6,null);
+        testCPU(src,"arm"      , "SystemV", 3,null);
     }
 
     @Test public void testStringExport() throws IOException {
diff --git a/chapter22/src/test/java/com/seaofnodes/simple/progs/helloWorld.smp b/chapter22/src/test/java/com/seaofnodes/simple/progs/helloWorld.smp
index b83a055c..07ff935f 100644
--- a/chapter22/src/test/java/com/seaofnodes/simple/progs/helloWorld.smp
+++ b/chapter22/src/test/java/com/seaofnodes/simple/progs/helloWorld.smp
@@ -1,4 +1,3 @@
 // -*- mode: java;  -*-
-i64 buf = "Hello, World!";
-sys.libc.write(1,buf,13);
+sys.io.p("Hello, World!");
 return 0;
diff --git a/chapter22/src/test/java/com/seaofnodes/simple/progs/jig.smp b/chapter22/src/test/java/com/seaofnodes/simple/progs/jig.smp
index b3bbf722..2d8d375b 100644
--- a/chapter22/src/test/java/com/seaofnodes/simple/progs/jig.smp
+++ b/chapter22/src/test/java/com/seaofnodes/simple/progs/jig.smp
@@ -1,10 +1,15 @@
 // -*- mode: java;  -*-
-struct s0 {
-    u16 v0;
-    i16 v3;
-    u32 v5;
+// theory: conservative approx to a CG will link all target fcsn.
+// unlinked *local* fcns with *no* TFP constants can be declared unreachable and removed.
+
+// Newtons approximation to the square root
+val sqrt = { int x ->
+    int guess = x;
+    while( 1 ) {
+        int next = (x/guess + guess)/2;
+        if( next == guess ) return guess;
+        guess = next;
+    }
 };
-return new s0.v3;
-if(0)
-    while(new s0.v5+new s0.v5) return 0;
-return new s0.v0;
+int cast_int = arg+2;
+return sqrt(arg) + sqrt(cast_int);