Define a new graph interaction API

1 files changed, 38 insertions, 0 deletions

diff --git a/chapter04/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java b/chapter04/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java
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+++ b/chapter04/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java
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+package com.seaofnodes.simple.print;
+
+import com.seaofnodes.graph.GraphAdapter;
+import com.seaofnodes.graph.GraphSnapshot;
+import com.seaofnodes.graph.GraphSnapshot.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.node.Node;
+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 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); }
+    @Override protected int nOuts(Node n) { return n.nOuts(); }
+    @Override protected Node out(Node n, int idx) { return n.out(idx); }
+
+    private ArrayList<Edge> edges(Node n) {
+        String[] names = n instanceof ScopeNode scope ? scope.reverseNames() : null;
+        var edges = new ArrayList<Edge>();
+        for( int i = 0; i < n.nIns(); i++ ) {
+            Role role = n instanceof ScopeNode || n instanceof ConstantNode ? Role.ASSOC
+                : n instanceof ProjNode ? (n.isCFG() ? Role.CTRL : Role.DATA)
+                : i == 0 ? Role.CTRL : Role.DATA;
+            edges.add(new Edge(i, ref(n.in(i)), role, names == null ? null : names[i]));
+        }
+        return edges;
+    }
+
+    @Override protected GraphSnapshot.Node desc(Node n) {
+        Projection proj = n instanceof ProjNode p
+            ? new Projection(n.nIns() == 0 ? 0 : ref(n.in(0)), p._idx) : null;
+        Kind kind = n instanceof ScopeNode ? Kind.SCOPE : n.isCFG() ? Kind.CTRL : Kind.DATA;
+        String label = n.label();
+        return new GraphSnapshot.Node(n._nid, label == null ? n.getClass().getSimpleName() : label,
+                                      n._type == null ? null : n._type.toString(), kind, edges(n), proj);
+    }
+}