Split from ch25, SCCP and interprocedural SCCPmain

1 files changed, 56 insertions, 0 deletions

diff --git a/chapter-sccp/src/main/java/com/seaofnodes/simple/Var.java b/chapter-sccp/src/main/java/com/seaofnodes/simple/Var.java
new file mode 100644
index 00000000..e13b85c5
--- /dev/null
+++ b/chapter-sccp/src/main/java/com/seaofnodes/simple/Var.java
@@ -0,0 +1,56 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.type.*;
+
+
+/**
+ *  The tracked fields are now complex enough to deserve a array-of-structs layout
+ */
+public class Var {
+
+    public final String _name;   // Declared name
+    // These fields are not final for forward reference late updates or
+    // promotions.
+    public int _idx;             // index in containing scope
+    private Type _type;          // Declared type
+    public boolean _init;        // Explicit declaration initializer
+    public boolean _final;       // Final field
+    public boolean _fref;        // Forward ref
+    public Parser.Lexer _loc;    // Source location
+
+    public Var(int idx, String name, Type type, boolean xfinal, Parser.Lexer loc ) {
+        this(idx,name,type,xfinal,loc,false);
+    }
+    public Var(int idx, String name, Type type, boolean xfinal, Parser.Lexer loc, boolean fref) {
+        _idx = idx;
+        _name = name;
+        _type = type;
+        _final = xfinal;
+        _fref = fref;
+        _loc = loc;
+    }
+    // Raw declared type, without resolving a forward reference while printing.
+    public Type _type() { return _type; }
+    public Type type() {
+        if( !_type.isFRef() ) return _type;
+        // Update self to no longer use the forward ref type
+        Type def = Parser.TYPES.get(((TypeMemPtr)_type)._obj._name);
+        return (_type=_type.meet(def));
+    }
+
+    // Forward reference variables (not types) must be BOTTOM and
+    // distinct from inferred variables
+    public boolean isFRef() { return _fref; }
+
+    public void defFRef( Type type, boolean xfinal, Parser.Lexer loc ) {
+        assert isFRef() && xfinal;
+        _type = type;
+        _final = true;
+        _fref = false;
+        _loc = loc;
+    }
+
+    @Override public String toString() {
+        return _type.toString()+(_final ? " ": " !")+_name;
+    }
+}