import org.ibex.classgen.util.*;
-// FEATURE: Add a "hit count" to each entry and optimize the table
-
class CPGen {
- private Hashtable entries = new Hashtable();
- private int nextIndex = 1; // 0 is reserved
- private int count;
- private int state;
+ private final Hashtable entries = new Hashtable();
+ private Ent[] entriesByIndex; // only valid when stable
+
+ 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
/*
* Entries
*/
- abstract static class Ent {
- int index;
+ public abstract static class Ent {
+ CPGen owner; // don't need this yet, but we will to implement ref() and unref()
+ int n; // this is the refcount if state == OPEN, index if >= STABLE
int tag;
- Ent(int tag) { this.tag = tag; }
-
- int getIndex() { return index; }
+ Ent(CPGen owner, int tag) { this.owner = owner; 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 Object key() throws ClassGen.ClassReadExn; // be careful using this, it drags in a bunch of code
}
- static class OneU4Ent extends Ent {
+ // INVARIANTS: tag == 3 || tag == 4
+ static class IntEnt extends Ent {
int i;
- OneU4Ent(int tag) { super(tag); }
+ IntEnt(CPGen owner, int tag) { super(owner, tag); }
void dump(DataOutput o) throws IOException { super.dump(o); o.writeInt(i); }
+ Object key() {
+ switch(tag) {
+ case 3: return new Integer(i);
+ case 4: return new Float(Float.intBitsToFloat(i));
+ default: throw new Error("should never happen");
+ }
+ }
}
+ // INVARIANTS: tag == 5 || tag == 6
static class LongEnt extends Ent {
long l;
- LongEnt(int tag) { super(tag); }
+ LongEnt(CPGen owner, int tag) { super(owner, tag); }
void dump(DataOutput o) throws IOException { super.dump(o); o.writeLong(l); }
+ Object key() {
+ switch(tag) {
+ case 5: return new Long(l);
+ case 6: return new Double(Double.longBitsToDouble(l));
+ default: throw new Error("should never happen");
+ }
+ }
}
+ /* INVARIANTS:
+ tag >= 7 && tag <= 12
+ if(tag == 7 || tag == 8) e0 instanceof Utf8Ent
+ if(tag == 9 || tag == 10 || tag == 11) {
+ e0 instanceof CPRefEnt && e0.tag == 7
+ e1 instanceof CPRefEnt && e0.tag == 12
+ }
+ if(tag == 12) {
+ e0 instanceof Utf8Ent
+ }
+ */
static class CPRefEnt extends Ent {
Ent e1;
Ent e2;
- CPRefEnt(int tag) { super(tag); }
+ CPRefEnt(CPGen owner, int tag) { super(owner, tag); }
+
+ String debugToString() { return "[" + e1.n + ":" + e1.debugToString() + (e2 == null ? "" : " + " + e2.n + ":" + e2.debugToString()) + "]"; }
+
void dump(DataOutput o) throws IOException {
super.dump(o);
- o.writeShort(e1.index);
- if(e2 != null) o.writeShort(e2.index);
+ o.writeShort(e1.n);
+ if(e2 != null) o.writeShort(e2.n);
+ }
+
+ private String fixme() { throw new Error("fixme"); }
+ Object key() throws ClassGen.ClassReadExn {
+ switch(tag) {
+ case 7: return Type.fromDescriptor(((Utf8Ent)e1).s);
+ case 8: return (((Utf8Ent)e1).s);
+ case 9: {
+ NameAndTypeKey nt = (NameAndTypeKey) e2.key();
+ Type t = Type.fromDescriptor(nt.type);
+ if(t == null) throw new ClassGen.ClassReadExn("invalid type descriptor");
+ return new FieldRef((Type.Class)e1.key(), nt.name, t);
+ }
+ case 10: case 11: {
+ NameAndTypeKey nt = (NameAndTypeKey) e2.key();
+ if (e1.key() == null) throw new Error(e1.tag + " => " + e1.key());
+ return new MethodRef((Type.Class)e1.key(), "methodname", Type.VOID, new Type[0]); // FIXME FIXME
+ }
+ case 12: {
+ return new NameAndTypeKey(((Utf8Ent)e1).s, ((Utf8Ent)e2).s);
+ }
+ }
+ throw new Error("FIXME " + tag);
}
}
static class Utf8Ent extends Ent {
String s;
- Utf8Ent() { super(1); }
+ Utf8Ent(CPGen owner) { super(owner, 1); }
+ String debugToString() { return s; }
void dump(DataOutput o) throws IOException { super.dump(o); o.writeUTF(s); }
+ Object key() {
+ return s;
+ }
}
/*
* Cache Keys
*/
- static class Utf8Key {
+ public static class Utf8Key {
String s;
public Utf8Key(String s) { this.s = s; }
public boolean equals(Object o) { return o instanceof Utf8Key && ((Utf8Key)o).s.equals(s); }
public int hashCode() { return ~s.hashCode(); }
}
- static class NameAndTypeKey {
+ public static class NameAndTypeKey {
String name;
String type;
NameAndTypeKey(String name, String type) { this.name = name; this.type = type; }
/*
* Methods
*/
- public void seal() { if(state > SEALED) throw new IllegalStateException(); state = SEALED; }
- public void stable() { if(state > STABLE) throw new IllegalStateException(); state = STABLE; }
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 e.getIndex();
+ return getIndex(e);
+ }
+ public final String getUtf8ByIndex(int i) {
+ return ((Utf8Ent)getByIndex(i)).s;
}
public final int getUtf8Index(String s) {
Ent e = getUtf8(s);
if(e == null) throw new IllegalStateException("entry not found");
- return e.getIndex();
+ 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 Type getType(int index) throws ClassGen.ClassReadExn {
+ Ent e = getByIndex(index);
+ if (e instanceof Utf8Ent) return Type.fromDescriptor(((Utf8Ent)e).s);
+ else return (Type)e.key();
+ }
+
+ public final Ent getByIndex(int index) {
+ if(state < STABLE) throw new IllegalStateException("constant pool is not stable");
+ Ent e;
+ if(index >= 65536 || index >= entriesByIndex.length || (e = entriesByIndex[index]) == null)
+ throw new IllegalStateException("invalid cp index");
+ return e;
}
- public final Ent addNameAndType(String name, String descriptor) { return add(new NameAndTypeKey(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(state == SEALED) throw new IllegalStateException("constant pool is sealed");
Ent ent = get(o);
- if(ent != null) return ent;
+ if(ent != null) {
+ if(state == OPEN) ent.n++;
+ return ent;
+ }
- if(o instanceof Type.Object) {
- CPRefEnt ce = new CPRefEnt(7);
- ce.e1 = addUtf8(((Type.Object)o).internalForm());
+ if(o instanceof Type.Class) {
+ CPRefEnt ce = new CPRefEnt(this, 7);
+ ce.e1 = addUtf8(((Type.Class)o).internalForm());
ent = ce;
} else if(o instanceof String) {
- CPRefEnt ce = new CPRefEnt(8);
+ CPRefEnt ce = new CPRefEnt(this, 8);
ce.e1 = addUtf8((String)o);
ent = ce;
} else if(o instanceof Integer) {
- OneU4Ent ue = new OneU4Ent(3);
+ IntEnt ue = new IntEnt(this, 3);
ue.i = ((Integer)o).intValue();
ent = ue;
} else if(o instanceof Float) {
- OneU4Ent ue = new OneU4Ent(4);
+ IntEnt ue = new IntEnt(this, 4);
ue.i = Float.floatToIntBits(((Float)o).floatValue());
ent = ue;
} else if(o instanceof Long) {
- LongEnt le = new LongEnt(5);
+ LongEnt le = new LongEnt(this, 5);
le.l = ((Long)o).longValue();
ent = le;
} else if(o instanceof Double) {
- LongEnt le = new LongEnt(6);
+ LongEnt le = new LongEnt(this, 6);
le.l = Double.doubleToLongBits(((Double)o).doubleValue());
ent = le;
} else if(o instanceof Utf8Key) {
- Utf8Ent ue = new Utf8Ent();
+ Utf8Ent ue = new Utf8Ent(this);
ue.s = ((Utf8Key)o).s;
ent = ue;
} else if(o instanceof NameAndTypeKey) {
- CPRefEnt ce = new CPRefEnt(12);
+ CPRefEnt ce = new CPRefEnt(this, 12);
NameAndTypeKey key = (NameAndTypeKey) o;
ce.e1 = addUtf8(key.name);
ce.e2 = addUtf8(key.type);
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);
+ CPRefEnt ce = new CPRefEnt(this, tag);
ce.e1 = add(key.klass);
- ce.e2 = addNameAndType(key.name,key.descriptor);
+ ce.e2 = addNameAndType(key.name, key.descriptor);
ent = ce;
} else {
throw new IllegalArgumentException("Unknown type passed to add");
}
- int spaces = ent instanceof LongEnt ? 2 : 1;
+ int spaces = ent instanceof LongEnt ? 2 : 1;
+ if(usedSlots + spaces > 65536) throw new ClassGen.Exn("constant pool full");
- if(nextIndex + spaces > 65536) throw new ClassGen.Exn("constant pool full");
-
- ent.index = nextIndex;
- nextIndex += spaces;
- count++;
+ ent.n = state == OPEN ? 1 : usedSlots; // refcount or index
+
+ usedSlots += spaces;
- entries.put(o,ent);
+ entries.put(o, ent);
return ent;
}
- public int size() { return nextIndex; }
+ public int slots() { return usedSlots; }
+
+ public void seal() { state = SEALED; }
- private static final Sort.CompareFunc compareFunc = new Sort.CompareFunc() {
- public int compare(Object a_, Object b_) {
- return ((Ent)a_).index - ((Ent)b_).index;
- }
- };
- public void dump(DataOutput o) throws IOException {
+ 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());
if(i != count) throw new Error("should never happen");
- Sort.sort(ents,compareFunc);
- for(i=0;i<ents.length;i++) {
- //System.err.println("" + (i+1) + ": " + ents[i]);
+ return ents;
+ }
+
+ private void assignIndex(Ent[] ents) {
+ int index = 1;
+ entriesByIndex = new Ent[ents.length*2];
+ for(int i=0;i<ents.length;i++) {
+ Ent ent = ents[i];
+ ent.n = index;
+ entriesByIndex[index] = ent;
+ 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 unsafeReopen() {
+ if(state == OPEN) return;
+ for(int i=1;i<entriesByIndex.length;i++) {
+ Ent e = entriesByIndex[i];
+ if(e == null) continue;
+ e.n = 0;
+ }
+ entriesByIndex = null;
+ state = OPEN;
+ }
+
+ public void dump(DataOutput o) throws IOException {
+ Ent[] ents = asArray();
+ Sort.sort(ents, compareFunc);
+ o.writeShort(usedSlots);
+ for(int i=0;i<ents.length;i++) {
+ //System.err.println("" + ents[i].n + ": " + ents[i].debugToString());
ents[i].dump(o);
}
}
+
+ CPGen(DataInput in) throws ClassGen.ClassReadExn, IOException {
+ usedSlots = in.readUnsignedShort();
+ if(usedSlots==0) throw new ClassGen.ClassReadExn("invalid used slots");
+
+ // these are to remember the CPRefEnt e1 and e2s we have to fix up
+ int[] e1s = new int[usedSlots];
+ int[] e2s = new int[usedSlots];
+
+ entriesByIndex = new Ent[usedSlots];
+
+ for(int index=1;index<usedSlots;index++) {
+ byte tag = in.readByte();
+ Ent e;
+ switch(tag) {
+ case 7: // Object Type
+ case 8: // String
+ case 9: // FieldRef
+ case 10: // MethodRef
+ case 11: // Instance Method Ref
+ case 12: // NameAndType
+ {
+ e = new CPRefEnt(this, tag);
+ e1s[index] = in.readUnsignedShort();
+ if(tag != 7 && tag != 8) e2s[index] = in.readUnsignedShort();
+ break;
+ }
+ case 3: // Integer
+ case 4: // Float
+ {
+ IntEnt ie;
+ e = ie = new IntEnt(this, tag);
+ ie.i = in.readInt();
+ break;
+ }
+ case 5: // Long
+ case 6: // Double
+ {
+ LongEnt le;
+ e = le = new LongEnt(this, tag);
+ le.l = in.readLong();
+ break;
+ }
+ case 1: // Utf8
+ {
+ Utf8Ent ue;
+ e = ue = new Utf8Ent(this);
+ ue.s = in.readUTF();
+ break;
+ }
+ default:
+ throw new ClassGen.ClassReadExn("invalid cp ent tag");
+ }
+ entriesByIndex[index] = e;
+ if (e instanceof LongEnt) index++;
+ }
+
+ for(int index=1;index<usedSlots;index++) {
+ int i = index;
+ Ent e = entriesByIndex[index];
+ if (e == null) throw new Error("should never happen: " + i + "/"+usedSlots);
+ if (e instanceof LongEnt) {
+ index++;
+ continue;
+ }
+ if (!(e instanceof CPRefEnt)) continue;
+ CPRefEnt ce = (CPRefEnt) e;
+ if(e1s[i] == 0 || e1s[i] >= usedSlots) throw new ClassGen.ClassReadExn("invalid cp index");
+ ce.e1 = entriesByIndex[e1s[i]];
+ if(ce.e1 == null) throw new ClassGen.ClassReadExn("invalid cp index");
+ if(ce.tag != 7 && ce.tag != 8) {
+ if(e2s[i] == 0 || e2s[i] >= usedSlots) throw new ClassGen.ClassReadExn("invalid cp index");
+ ce.e2 = entriesByIndex[e2s[i]];
+ if(ce.e2 == null) throw new ClassGen.ClassReadExn("invalid cp index");
+ }
+ switch(ce.tag) {
+ case 7:
+ case 8:
+ if(!(ce.e1 instanceof Utf8Ent)) throw new ClassGen.ClassReadExn("expected a utf8 ent");
+ break;
+ case 9:
+ case 10:
+ case 11:
+ if(!(ce.e1 instanceof CPRefEnt) || ((CPRefEnt)ce.e1).tag != 7)
+ throw new ClassGen.ClassReadExn("expected a type ent");
+ if(!(ce.e2 instanceof CPRefEnt) || ((CPRefEnt)ce.e2).tag != 12)
+ throw new ClassGen.ClassReadExn("expected a name and type ent");
+ break;
+ case 12:
+ if(!(ce.e1 instanceof Utf8Ent)) throw new ClassGen.ClassReadExn("expected a utf8 ent");
+ if(!(ce.e2 instanceof Utf8Ent)) throw new ClassGen.ClassReadExn("expected a utf8 ent");
+ break;
+ }
+ }
+ for(int i=1; i<usedSlots; i++) {
+ Ent e = entriesByIndex[i];
+ entries.put(e.key(), e);
+ if (e instanceof LongEnt) i++;
+ }
+ state = STABLE;
+ }
}