import org.ibex.classgen.util.*;
-public class CPGen {
- private Hashtable entries = new Hashtable();
- private int nextIndex = 1; // 0 is reserved
- private boolean sealed;
+class CPGen {
+ private final Hashtable entries = new Hashtable();
+ private int usedSlots = 1; // 0 is reserved
+ private int state = OPEN;
+ private static final int OPEN = 0;
+ private static final int STABLE = 1; // existing entries won't change
+ private static final int SEALED = 2; // no new entries
CPGen() { }
/*
* Entries
*/
- abstract static class Ent implements Sort.Comparable {
- int index;
- public abstract int tag();
- public void dump(DataOutput o) throws IOException { o.writeByte(tag()); }
- public int compareTo(Object o) {
- if(!(o instanceof Ent)) return 1;
- int oi = ((Ent)o).index;
- if(index < oi) return -1;
- if(index > oi) return 1;
- return 0;
- }
+ abstract static class Ent {
+ int n; // this is the refcount if state == OPEN, index if >= STABLE
+ int tag;
+
+ Ent(int tag) { this.tag = tag; }
+
+ void dump(DataOutput o) throws IOException { o.writeByte(tag); }
+ String debugToString() { return toString(); } // so we can remove this method when not debugging
}
- abstract static class OneU2Ent extends Ent { int i; public void dump(DataOutput o) throws IOException { super.dump(o); o.writeShort(i); } }
- abstract static class OneU4Ent extends Ent { int i; public void dump(DataOutput o) throws IOException { super.dump(o); o.writeInt(i); } }
- abstract static class TwoU2Ent extends OneU2Ent { int i2; public void dump(DataOutput o) throws IOException { super.dump(o); o.writeShort(i2); } }
- abstract static class TwoU4Ent extends OneU4Ent { int i2; public void dump(DataOutput o) throws IOException { super.dump(o); o.writeInt(i2); } }
-
- static class IntEnt extends OneU4Ent { public int tag() { return 3; } } // word1: bytes
- static class FloatEnt extends OneU4Ent { public int tag() { return 4; } } // word1: bytes
- static class LongEnt extends TwoU4Ent { public int tag() { return 5; } } // word1/2: bytes
- static class DoubleEnt extends TwoU4Ent { public int tag() { return 6; } } // word1/2: bytes
- static class ClassEnt extends OneU2Ent { public int tag() { return 7; } } // word1: name_index
- static class StringEnt extends OneU2Ent { public int tag() { return 8; } } // word1: string_index
- static class FieldRefEnt extends TwoU2Ent { public int tag() { return 9; } } // word1: class_index word2: name_and_type_index
- static class MethodRefEnt extends TwoU2Ent { public int tag() { return 10; } } // word1: class_index word2: name_and_type_index
- static class IMethodRefEnt extends TwoU2Ent { public int tag() { return 11; } } // word1: class_index word2: name_and_type_index
- static class NameAndTypeEnt extends TwoU2Ent { public int tag() { return 12; } } // word1: name_index word2: descriptor_index
+ static class IntEnt extends Ent {
+ int i;
+ IntEnt(int tag) { super(tag); }
+ void dump(DataOutput o) throws IOException { super.dump(o); o.writeInt(i); }
+ }
- static class Utf8Ent extends Ent {
- String s;
- public int tag() { return 1; }
- public void dump(DataOutput o) throws IOException {
+ static class LongEnt extends Ent {
+ long l;
+ LongEnt(int tag) { super(tag); }
+ void dump(DataOutput o) throws IOException { super.dump(o); o.writeLong(l); }
+ }
+
+ static class CPRefEnt extends Ent {
+ Ent e1;
+ Ent e2;
+ CPRefEnt(int tag) { super(tag); }
+
+ String debugToString() { return "[" + e1.n + ":" + e1.debugToString() + (e2 == null ? "" : " + " + e2.n + ":" + e2.debugToString()) + "]"; }
+
+ void dump(DataOutput o) throws IOException {
super.dump(o);
- o.writeUTF(s);
+ if(e1.n == 6 || (e2!=null && e2.n == 6)) System.err.println(debugToString() + " refs 6");
+ o.writeShort(e1.n);
+ if(e2 != null) o.writeShort(e2.n);
}
- public String toString() { return "Utf8: " + s; }
+ }
+
+ static class Utf8Ent extends Ent {
+ String s;
+ Utf8Ent() { super(1); }
+ String debugToString() { return s; }
+ void dump(DataOutput o) throws IOException { super.dump(o); o.writeUTF(s); }
}
/*
public boolean equals(Object o) { return o instanceof Utf8Key && ((Utf8Key)o).s.equals(s); }
public int hashCode() { return ~s.hashCode(); }
}
-
- public static class NameAndType {
+
+ static class NameAndTypeKey {
String name;
String type;
- public NameAndType(String name, String type) { this.name = name; this.type = type; }
+ NameAndTypeKey(String name, String type) { this.name = name; this.type = type; }
public boolean equals(Object o_) {
- if(!(o_ instanceof NameAndType)) return false;
- NameAndType o = (NameAndType) o_;
+ if(!(o_ instanceof NameAndTypeKey)) return false;
+ NameAndTypeKey o = (NameAndTypeKey) o_;
return o.name.equals(name) && o.type.equals(type);
}
public int hashCode() { return name.hashCode() ^ type.hashCode(); }
}
- static abstract class FieldMethodRef {
- Type.Object klass;
- NameAndType nameAndType;
- public FieldMethodRef(Type.Object klass, NameAndType nameAndType) { this.klass = klass; this.nameAndType = nameAndType; }
- public boolean equals(Object o_) {
- if(!(o_ instanceof FieldMethodRef)) return false;
- FieldMethodRef o = (FieldMethodRef) o_;
- return o.klass.equals(klass) && o.nameAndType.equals(nameAndType);
- }
- }
-
- public static class FieldRef extends FieldMethodRef { public FieldRef (Type.Object c, NameAndType t) { super(c,t); } }
- public static class MethodRef extends FieldMethodRef { public MethodRef (Type.Object c, NameAndType t) { super(c,t); } }
- public static class IMethodRef extends FieldMethodRef { public IMethodRef(Type.Object c, NameAndType t) { super(c,t); } }
-
/*
* Methods
*/
- public void seal() { sealed = true; }
public final Ent get(Object o) { return (Ent) entries.get(o); }
public final Ent getUtf8(String s) { return get(new Utf8Key(s)); }
+ public final int getIndex(Object o) {
+ Ent e = get(o);
+ if(e == null) throw new IllegalStateException("entry not found");
+ return getIndex(e);
+ }
+ public final int getUtf8Index(String s) {
+ Ent e = getUtf8(s);
+ if(e == null) throw new IllegalStateException("entry not found");
+ return getIndex(e);
+ }
+ public final int getIndex(Ent ent) {
+ if(state < STABLE) throw new IllegalStateException("constant pool is not stable");
+ return ent.n;
+ }
- public final Ent addNameAndType(String name, String descriptor) { return add(new NameAndType(name,descriptor)); }
+ public final Ent addNameAndType(String name, String descriptor) { return add(new NameAndTypeKey(name,descriptor)); }
public final Ent addUtf8(String s) { return add(new Utf8Key(s)); }
public final Ent add(Object o) {
- if(sealed) throw new IllegalStateException("constant pool is sealed");
+ if(state == SEALED) throw new IllegalStateException("constant pool is sealed");
Ent ent = get(o);
- if(ent != null) return ent;
-
- if(nextIndex == 65536) throw new ClassGen.Exn("constant pool full");
+ if(ent != null) {
+ if(state == OPEN) ent.n++;
+ return ent;
+ }
if(o instanceof Type.Object) {
- ClassEnt ce = new ClassEnt();
- ce.i = addUtf8(((Type.Object)o).internalForm()).index;
+ CPRefEnt ce = new CPRefEnt(7);
+ ce.e1 = addUtf8(((Type.Object)o).internalForm());
ent = ce;
} else if(o instanceof String) {
- StringEnt se = new StringEnt();
- se.i = addUtf8((String)o).index;
- ent = se;
+ CPRefEnt ce = new CPRefEnt(8);
+ ce.e1 = addUtf8((String)o);
+ ent = ce;
} else if(o instanceof Integer) {
- IntEnt ie = new IntEnt();
- ie.i = ((Integer)o).intValue();
- ent = ie;
+ IntEnt ue = new IntEnt(3);
+ ue.i = ((Integer)o).intValue();
+ ent = ue;
} else if(o instanceof Float) {
- FloatEnt fe = new FloatEnt();
- fe.i = Float.floatToIntBits(((Float)o).floatValue());
- ent = fe;
+ IntEnt ue = new IntEnt(4);
+ ue.i = Float.floatToIntBits(((Float)o).floatValue());
+ ent = ue;
} else if(o instanceof Long) {
- LongEnt le = new LongEnt();
- long l = ((Long)o).longValue();
- le.i = (int)(l>>>32);
- le.i2 = (int)l;
+ LongEnt le = new LongEnt(5);
+ le.l = ((Long)o).longValue();
ent = le;
} else if(o instanceof Double) {
- DoubleEnt de = new DoubleEnt();
- long l = Double.doubleToLongBits(((Double)o).doubleValue());
- de.i = (int)(l>>>32);
- de.i2 = (int)l;
- ent = de;
+ LongEnt le = new LongEnt(6);
+ le.l = Double.doubleToLongBits(((Double)o).doubleValue());
+ ent = le;
} else if(o instanceof Utf8Key) {
Utf8Ent ue = new Utf8Ent();
ue.s = ((Utf8Key)o).s;
ent = ue;
- } else if(o instanceof NameAndType) {
- NameAndTypeEnt ne = new NameAndTypeEnt();
- NameAndType key = (NameAndType) o;
- ne.i = addUtf8(key.name).index;
- ne.i2 = addUtf8(key.type).index;
- ent = ne;
- } else if(o instanceof FieldMethodRef) {
- FieldMethodRef key = (FieldMethodRef) o;
- TwoU2Ent fme;
- if(o instanceof MethodRef) fme = new MethodRefEnt();
- else if(o instanceof IMethodRef) fme = new IMethodRefEnt();
- else if(o instanceof FieldRef) fme = new FieldRefEnt();
- else throw new Error("should never happen");
- fme.i = add(key.klass).index;
- fme.i2 = add(key.nameAndType).index;
- ent = fme;
+ } else if(o instanceof NameAndTypeKey) {
+ CPRefEnt ce = new CPRefEnt(12);
+ NameAndTypeKey key = (NameAndTypeKey) o;
+ ce.e1 = addUtf8(key.name);
+ ce.e2 = addUtf8(key.type);
+ ent = ce;
+ } else if(o instanceof ClassGen.FieldOrMethodRef) {
+ ClassGen.FieldOrMethodRef key = (ClassGen.FieldOrMethodRef) o;
+ int tag = o instanceof FieldRef ? 9 : o instanceof MethodRef ? 10 : o instanceof MethodRef.I ? 11 : 0;
+ if(tag == 0) throw new Error("should never happen");
+ CPRefEnt ce = new CPRefEnt(tag);
+ ce.e1 = add(key.klass);
+ ce.e2 = addNameAndType(key.name,key.descriptor);
+ ent = ce;
} else {
throw new IllegalArgumentException("Unknown type passed to add");
}
- ent.index = nextIndex++;
+ int spaces = ent instanceof LongEnt ? 2 : 1;
+ if(usedSlots + spaces > 65536) throw new ClassGen.Exn("constant pool full");
+
+ ent.n = state == OPEN ? 1 : usedSlots; // refcount or index
+
+ usedSlots += spaces;
+
entries.put(o,ent);
return ent;
}
- public int size() { return nextIndex; }
+ public int slots() { return usedSlots; }
+
+ public void seal() { state = SEALED; }
- public void dump(DataOutput o) throws IOException {
- Ent[] ents = new Ent[nextIndex-1];
+ private Ent[] asArray() {
+ int count = entries.size();
+ Ent[] ents = new Ent[count];
int i=0;
Enumeration e = entries.keys();
while(e.hasMoreElements()) ents[i++] = (Ent) entries.get(e.nextElement());
- Sort.sort(ents);
- for(i=0;i<ents.length;i++) {
- //System.err.println("" + (i+1) + ": " + ents[i]);
+ if(i != count) throw new Error("should never happen");
+ return ents;
+ }
+
+ private static void assignIndex(Ent[] ents) {
+ int index = 1;
+ for(int i=0;i<ents.length;i++) {
+ Ent ent = ents[i];
+ ent.n = index;
+ index += ent instanceof LongEnt ? 2 : 1;
+ }
+ }
+
+ public void stable() {
+ if(state != OPEN) return;
+ state = STABLE;
+ assignIndex(asArray());
+ }
+
+ private static final Sort.CompareFunc compareFunc = new Sort.CompareFunc() {
+ public int compare(Object a_, Object b_) {
+ return ((Ent)a_).n - ((Ent)b_).n;
+ }
+ };
+
+ private static final Sort.CompareFunc reverseCompareFunc = new Sort.CompareFunc() {
+ public int compare(Object a_, Object b_) {
+ return ((Ent)b_).n - ((Ent)a_).n;
+ }
+ };
+
+ public void optimize() {
+ if(state != OPEN) throw new IllegalStateException("can't optimize a stable constant pool");
+ Ent[] ents = asArray();
+ Sort.sort(ents,reverseCompareFunc);
+ state = STABLE;
+ assignIndex(ents);
+ }
+
+ public void dump(DataOutput o) throws IOException {
+ Ent[] ents = asArray();
+ Sort.sort(ents,compareFunc);
+ for(int i=0;i<ents.length;i++) {
+ //System.err.println("" + ents[i].n + ": " + ents[i].debugToString());
ents[i].dump(o);
}
}