Graph viewer on ch4 and25

5 files changed, 70 insertions, 3 deletions

diff --git a/chapter04/src/main/java/com/seaofnodes/simple/Parser.java b/chapter04/src/main/java/com/seaofnodes/simple/Parser.java
index ff2c0504..360a7be9 100644
--- a/chapter04/src/main/java/com/seaofnodes/simple/Parser.java
+++ b/chapter04/src/main/java/com/seaofnodes/simple/Parser.java
@@ -1,5 +1,6 @@
 package com.seaofnodes.simple;
 
+import com.seaofnodes.graph.GraphObserver;
 import com.seaofnodes.simple.node.*;
 import com.seaofnodes.simple.type.*;
 
@@ -23,6 +24,11 @@ public class Parser {
      * To make the compiler multithreaded, this field will have to move into a TLS.
      */
     public static StartNode START;
+    // Current compilation context, like START; the observer belongs to the parser.
+    public static Parser PARSER;
+    public GraphObserver<Node> _obs;
+    public ReturnNode _ret;
+    public int pos() { return _lexer._position; }
 
     // The Lexer.  Thin wrapper over a byte[] buffer with a cursor.
     private final Lexer _lexer;
@@ -43,6 +49,7 @@ public class Parser {
 
 
     public Parser(String source, TypeInteger arg) {
+        PARSER = this;
         Node.reset();
         _lexer = new Lexer(source);
         _scope = new ScopeNode();
@@ -76,6 +83,8 @@ public class Parser {
         _scope.pop();
         if (!_lexer.isEOF()) throw error("Syntax error, unexpected " + _lexer.getAnyNextToken());
         if( show ) showGraph();
+        _ret = ret;
+        if( _obs != null ) _obs.phase("Parse");
         return ret;
     }
 
diff --git a/chapter04/src/main/java/com/seaofnodes/simple/node/Node.java b/chapter04/src/main/java/com/seaofnodes/simple/node/Node.java
index 2c0e3832..58516151 100644
--- a/chapter04/src/main/java/com/seaofnodes/simple/node/Node.java
+++ b/chapter04/src/main/java/com/seaofnodes/simple/node/Node.java
@@ -1,6 +1,7 @@
 package com.seaofnodes.simple.node;
 
 import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.Parser;
 import com.seaofnodes.simple.type.Type;
 
 import java.util.*;
@@ -202,7 +203,7 @@ public abstract class Node {
     }
 
     // Mostly used for asserts and printing.
-    boolean isDead() { return isUnused() && nIns()==0 && _type==null; }
+    public boolean isDead() { return isUnused() && nIns()==0 && _type==null; }
 
     // Shortcuts to stop DCE mid-parse
     // Add bogus null use to keep node alive
@@ -234,11 +235,21 @@ public abstract class Node {
      * </ul>
      */
     public final Node peephole( ) {
+        var obs = Parser.PARSER == null ? null : Parser.PARSER._obs;
+        Type old = _type;
+        if( obs != null ) obs.before(this);
+        Node n = peepholeOpt();
+        Node rez = n == null ? this : n;
+        if( obs != null ) obs.after(this, n != null || old != _type ? rez : null, false);
+        return rez;
+    }
+
+    private Node peepholeOpt() {
         // Compute initial or improved Type
         Type type = _type = compute();
 
         if (_disablePeephole)
-            return this;        // Peephole optimizations turned off
+            return null;        // Peephole optimizations turned off
 
         // Replace constant computations from non-constants with a constant node
         if (!(this instanceof ConstantNode) && type.isConstant())
@@ -252,7 +263,7 @@ public abstract class Node {
             // Recursively optimize
             return deadCodeElim(n.peephole());
 
-        return this;            // No progress
+        return null;            // No progress
     }
 
     // m is the new Node, self is the old.
diff --git a/chapter04/src/main/java/com/seaofnodes/simple/print/JSViewer.java b/chapter04/src/main/java/com/seaofnodes/simple/print/JSViewer.java
new file mode 100644
index 00000000..43b0be2f
--- /dev/null
+++ b/chapter04/src/main/java/com/seaofnodes/simple/print/JSViewer.java
@@ -0,0 +1,26 @@
+package com.seaofnodes.simple.print;
+
+import com.seaofnodes.graph.*;
+import com.seaofnodes.simple.Parser;
+import java.io.IOException;
+
+public class JSViewer extends GraphViewer {
+    public static void main(String[] args) throws IOException {
+        try( var view = new JSViewer() ) { view.run(); }
+    }
+    JSViewer() throws IOException {}
+
+    @Override protected void compile(String src) {
+        Parser parser = new Parser(src);
+        parser._obs = new SimpleGraphObserver(parser) {
+            @Override protected void frame(GraphSnapshot snap, int pos, GraphEvent evt) throws IOException {
+                JSViewer.this.frame(snap, pos, evt);
+            }
+        };
+        try {
+            parser.parse();
+        } finally {
+            parser._obs = null;
+        }
+    }
+}
diff --git a/chapter04/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java b/chapter04/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java
index 0755613b..72a11a87 100644
--- a/chapter04/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java
+++ b/chapter04/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java
@@ -9,6 +9,7 @@ import java.util.ArrayList;
 
 /** Chapter 4's view of the IR; no knowledge of browser, transport or layout. */
 public class SimpleGraphAdapter extends GraphAdapter<Node> {
+    @Override protected boolean dead(Node n) { return n.isDead(); }
     @Override protected int id(Node n) { return n._nid; }
     @Override protected int nIns(Node n) { return n.nIns(); }
     @Override protected Node in(Node n, int idx) { return n.in(idx); }
diff --git a/chapter04/src/main/java/com/seaofnodes/simple/print/SimpleGraphObserver.java b/chapter04/src/main/java/com/seaofnodes/simple/print/SimpleGraphObserver.java
new file mode 100644
index 00000000..865d1e20
--- /dev/null
+++ b/chapter04/src/main/java/com/seaofnodes/simple/print/SimpleGraphObserver.java
@@ -0,0 +1,20 @@
+package com.seaofnodes.simple.print;
+
+import com.seaofnodes.graph.GraphCapture;
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.node.Node;
+import java.util.ArrayList;
+
+/** Chapter 4 needs only a parser; it has no worklist or distant dependencies. */
+public abstract class SimpleGraphObserver extends GraphCapture<Node> {
+    private final Parser _parser;
+    protected SimpleGraphObserver(Parser parser) { super(new SimpleGraphAdapter()); _parser = parser; }
+    @Override protected String phase() { return "Parse"; }
+    @Override protected int pos() { return _parser.pos(); }
+    @Override protected void detach() { _parser._obs = null; }
+    @Override protected void roots(ArrayList<Node> roots) {
+        roots.add(Parser.START);
+        roots.add(_parser._scope);
+        roots.add(_parser._ret);
+    }
+}