package org.ibex.classgen;
import java.io.*;
+import java.util.*;
+/** A class representing a method in a generated classfile
+ @see ClassFile#addMethod */
public class MethodGen implements CGConst {
- private final static boolean EMIT_NOPS = true;
+ private final static boolean EMIT_NOPS = false;
+ private static final int NO_CODE = -1;
+ private static final int FINISHED = -2;
+
+ private final ClassFile owner;
private final CPGen cp;
private final String name;
private final Type ret;
private final Type[] args;
private final int flags;
- private final AttrGen attrs;
- private final AttrGen codeAttrs;
-
- private final int nameIndex;
- private final int descriptorIndex;
+ private final ClassFile.AttrGen attrs;
+ private final ClassFile.AttrGen codeAttrs;
+ private final Hashtable exnTable = new Hashtable();
+ private final Hashtable thrownExceptions = new Hashtable();
private int maxStack = 16;
- private int maxLocals=1;
+ private int maxLocals;
private int size;
private int capacity;
private byte[] op;
private Object[] arg;
- MethodGen(ClassGen owner, String name, Type ret, Type[] args, int flags) {
+ public String toString() { StringBuffer sb = new StringBuffer(); toString(sb, "<init>"); return sb.toString(); }
+ public void toString(StringBuffer sb, String constructorName) {
+ sb.append(ClassFile.flagsToString(flags));
+ sb.append(ret);
+ sb.append(" ");
+
+ if (name.equals("<clinit>")) sb.append("static ");
+ else {
+ if (name.equals("<init>")) sb.append(constructorName);
+ else sb.append(name);
+ sb.append("(");
+ for(int i=0; i<args.length; i++)
+ sb.append((i==0?"":", ")+args[i]);
+ sb.append(") ");
+ }
+ sb.append("{");
+ sb.append("}");
+ // FIXME: attrs, body
+ }
+
+ MethodGen(CPGen cp, DataInput in, ClassFile owner) throws IOException {
+ this.cp = cp;
+ this.owner = owner;
+ flags = in.readShort();
+ name = cp.getUtf8ByIndex(in.readShort());
+ String descriptor = cp.getUtf8ByIndex(in.readShort());
+ String ret = descriptor.substring(descriptor.indexOf(')')+1);
+ this.ret = Type.instance(ret);
+ //String args = descriptor.substring(1, descriptor.indexOf(')'));
+ args = new Type[0]; // FIXME
+ codeAttrs = null;
+ attrs = new ClassFile.AttrGen(cp, in);
+ }
+
+ MethodGen(ClassFile owner, String name, Type ret, Type[] args, int flags) {
if((flags & ~(ACC_PUBLIC|ACC_PRIVATE|ACC_PROTECTED|ACC_STATIC|ACC_FINAL|ACC_SYNCHRONIZED|ACC_NATIVE|ACC_ABSTRACT|ACC_STRICT)) != 0)
throw new IllegalArgumentException("invalid flags");
this.cp = owner.cp;
this.ret = ret;
this.args = args;
this.flags = flags;
+ this.owner = owner;
- attrs = new AttrGen(cp);
- codeAttrs = new AttrGen(cp);
+ attrs = new ClassFile.AttrGen(cp);
+ codeAttrs = new ClassFile.AttrGen(cp);
- nameIndex = cp.addUtf8(name).index;
- descriptorIndex = cp.addUtf8(descriptor()).index;
+ cp.addUtf8(name);
+ cp.addUtf8(owner.getType().method(name, ret, args).getDescriptor());
if((owner.flags & ACC_INTERFACE) != 0 || (flags & (ACC_ABSTRACT|ACC_NATIVE)) != 0) size = capacity = -1;
+
+ maxLocals = Math.max(args.length + (flags&ACC_STATIC)==0 ? 1 : 0, 4);
}
- public String descriptor() { return descriptor(ret,args); }
- public static String descriptor(Type ret, Type[] args) {
- StringBuffer sb = new StringBuffer(args.length*4);
- sb.append("(");
- for(int i=0;i<args.length;i++) sb.append(args[i].getDescriptor());
- sb.append(")");
- sb.append(ret.getDescriptor());
- return sb.toString();
+ private class ExnTableEnt {
+ public int start;
+ public int end;
+ public int handler;
+ public CPGen.Ent typeEnt;
+ public ExnTableEnt(int start, int end, int handler, CPGen.Ent typeEnt) {
+ this.start = start;
+ this.end = end;
+ this.handler = handler;
+ this.typeEnt = typeEnt;
+ }
+ public void dump(DataOutput o, int[] pc, int endPC) throws IOException {
+ o.writeShort(pc[start]);
+ o.writeShort(end==pc.length ? endPC : pc[end]);
+ o.writeShort(pc[handler]);
+ o.writeShort(cp.getIndex(typeEnt));
+ }
}
-
+
+ /** Adds an exception handler for the range [<i>start</i>, <i>end</i>) pointing to <i>handler</i>
+ @param start The instruction to start at (inclusive)
+ @param end The instruction to end at (exclusive)
+ @param handler The instruction of the excepton handler
+ @param type The type of exception that is to be handled (MUST inherit from Throwable)
+ */
+ public final void addExceptionHandler(int start, int end, int handler, Type.Class type) {
+ exnTable.put(type, new ExnTableEnt(start, end, handler, cp.add(type)));
+ }
+
+ /** Adds a exception type that can be thrown from this method
+ NOTE: This isn't enforced by the JVM. This is for reference only. A method can throw exceptions not declared to be thrown
+ @param type The type of exception that can be thrown
+ */
+ public final void addThrow(Type.Class type) {
+ thrownExceptions.put(type, cp.add(type));
+ }
+
private final void grow() { if(size == capacity) grow(size+1); }
private final void grow(int newCap) {
+ if(capacity == NO_CODE) throw new IllegalStateException("method can't have code");
+ if(capacity == FINISHED) throw new IllegalStateException("method has been finished");
if(newCap <= capacity) return;
- newCap = Math.max(newCap,capacity == 0 ? 256 : capacity*2);
+ newCap = Math.max(newCap, capacity == 0 ? 256 : capacity*2);
byte[] op2 = new byte[newCap];
- if(capacity != 0) System.arraycopy(op,0,op2,0,size);
+ if(capacity != 0) System.arraycopy(op, 0, op2, 0, size);
op = op2;
Object[] arg2 = new Object[newCap];
- if(capacity != 0) System.arraycopy(arg,0,arg2,0,size);
+ if(capacity != 0) System.arraycopy(arg, 0, arg2, 0, size);
arg = arg2;
capacity = newCap;
}
+
+ /** Returns the size (in instructions) of this method
+ @return The size of the method (in instructions)
+ */
public final int size() { return size; }
- public final int addPushConst(int n) { grow(); setPushConst(size,n); return size++; }
- public final int addPushConst(long n) { grow(); setPushConst(size,n); return size++; }
- public final int addPushConst(float n) { grow(); setPushConst(size,n); return size++; }
- public final int addPushConst(double n) { grow(); setPushConst(size,n); return size++; }
- public final int addPushConst(Object o) { grow(); setPushConst(size,o); return size++; }
- public final int add(byte op, int arg) { return add(op,N(arg)); }
- public final int add(byte op, Object arg) { grow(); set(size,op,arg); return size++; }
- public final int add(byte op) { return add(op,null); }
+ // These two are optimized for speed, they don't call set() below
+ /** Add a bytecode (with no argument) to the method */
+ public final int add(byte op) {
+ int s = size;
+ if(s == capacity) grow();
+ this.op[s] = op;
+ size++;
+ return s;
+ }
+ /** Set the bytecode at position <i>pos</i> to <i>op</i> */
+ public final void set(int pos, byte op) { this.op[pos] = op; }
- public final void set(int pos, byte op) { set(pos,op,null); }
- public final void set(int pos, byte op, int n) { set(pos,op,N(n)); }
+ /** Adds a bytecode, <i>op</i>, with argument <i>arg</i> to the method
+ @return The position of the new bytecode
+ */
+ public final int add(byte op, Object arg) { if(capacity == size) grow(); set(size, op, arg); return size++; }
+ /** Adds a bytecode with a boolean argument - equivalent to add(op, arg?1:0);
+ @return The position of the new bytecode
+ @see #add(byte, int)
+ */
+ public final int add(byte op, boolean arg) { if(capacity == size) grow(); set(size, op, arg); return size++; }
+ /** Adds a bytecode with an integer argument. This is equivalent to add(op, new Integer(arg)), but optimized to prevent the allocation when possible
+ @return The position of the new bytecode
+ @see #add(byte, Object)
+ */
+ public final int add(byte op, int arg) { if(capacity == size) grow(); set(size, op, arg); return size++; }
+
+ /** Gets the bytecode at position <i>pos</i>
+ @exception ArrayIndexOutOfBoundException if pos < 0 || pos >= size()
+ */
+ public final byte get(int pos) { return op[pos]; }
+
+ /** Gets the bytecode at position <i>pos</i>. NOTE: This isn't necessarily the same object that was set with add or set.
+ Arguments for instructions which access the constant pool (LDC, INVOKEVIRTUAL, etc) are converted to a more efficient
+ interal form when they are added. The value returned from this method for these instruction can be reused, but there
+ is no way to retrieve the original object
+ @exception ArrayIndexOutOfBoundException if pos < 0 || pos >= size()
+ */
+ public final Object getArg(int pos) { return arg[pos]; }
+
+ /** Sets the argument for <i>pos</i> to <i>arg</i>. This is equivalent to set(pos, op, new Integer(arg)), but optimized to prevent the allocation when possible.
+ @exception ArrayIndexOutOfBoundException if pos < 0 || pos >= size()
+ @see #setArg(int, Object) */
+ public final void setArg(int pos, int arg) { set(pos, op[pos], N(arg)); }
+ /** Sets the argument for <i>pos</i> to <i>arg</i>.
+ @exception ArrayIndexOutOfBoundException if pos < 0 || pos >= size()
+ */
+ public final void setArg(int pos, Object arg) { set(pos, op[pos], arg); }
+
+ /** Sets the bytecode and argument at <i>pos</i> to <i>op</i> and <i>arg</i> respectivly.
+ This is equivalent to set(pos, op, arg?1:0)
+ @exception ArrayIndexOutOfBoundException if pos < 0 || pos >= size()
+ */
+ public final void set(int pos, byte op, boolean arg) { set(pos, op, arg?1:0); }
+
+ // This MUST handle x{LOAD, STORE} and LDC with an int arg WITHOUT falling back to set(int, byte, Object)
+ /** Sets the bytecode and argument at <i>pos</i> to <i>op</i> and <i>n</i> respectivly.
+ This is equivalent to set(pos, op, new Integer(n)), but optimized to prevent the allocation when possible.
+ @exception ArrayIndexOutOfBoundException if pos < 0 || pos >= size()
+ */
+ public final void set(int pos, byte op, int n) {
+ Object arg = null;
+ OUTER: switch(op) {
+ case LDC:
+ switch(n) {
+ case -1: op = ICONST_M1; break OUTER;
+ case 0: op = ICONST_0; break OUTER;
+ case 1: op = ICONST_1; break OUTER;
+ case 2: op = ICONST_2; break OUTER;
+ case 3: op = ICONST_3; break OUTER;
+ case 4: op = ICONST_4; break OUTER;
+ case 5: op = ICONST_5; break OUTER;
+ }
+ if(n >= -128 && n <= 127) { op = BIPUSH; arg = N(n); }
+ else if(n >= -32768 && n <= 32767) { op = SIPUSH; arg = N(n); }
+ else { arg = cp.add(N(n)); }
+ break;
+ case ILOAD: case ISTORE: case LLOAD: case LSTORE: case FLOAD:
+ case FSTORE: case DLOAD: case DSTORE: case ALOAD: case ASTORE:
+ if(n >= maxLocals) maxLocals = n + 1;
+ if(n >= 0 && n <= 3) {
+ byte base = 0;
+ switch(op) {
+ case ILOAD: base = ILOAD_0; break;
+ case ISTORE: base = ISTORE_0; break;
+ case LLOAD: base = LLOAD_0; break;
+ case LSTORE: base = LSTORE_0; break;
+ case FLOAD: base = FLOAD_0; break;
+ case FSTORE: base = FSTORE_0; break;
+ case DLOAD: base = DLOAD_0; break;
+ case DSTORE: base = DSTORE_0; break;
+ case ALOAD: base = ALOAD_0; break;
+ case ASTORE: base = ASTORE_0; break;
+ }
+ op = (byte)((base&0xff) + n);
+ } else {
+ arg = N(n);
+ }
+ break;
+ default:
+ set(pos, op, N(n));
+ return;
+ }
+ this.op[pos] = op;
+ this.arg[pos] = arg;
+ }
+
+ /** Sets the bytecode and argument at <i>pos</i> to <i>op</i> and <i>arg</i> respectivly.
+ @exception ArrayIndexOutOfBoundException if pos < 0 || pos >= size()
+ */
public final void set(int pos, byte op, Object arg) {
- if(capacity == -1) throw new IllegalStateException("method can't have code");
- if(size == -1) throw new IllegalStateException("method is finalized");
- int iarg = arg instanceof Integer ? ((Integer)arg).intValue() : -1;
-
switch(op) {
- case LDC: if(iarg >= 256) op = LDC_W; break;
+ case ILOAD: case ISTORE: case LLOAD: case LSTORE: case FLOAD:
+ case FSTORE: case DLOAD: case DSTORE: case ALOAD: case ASTORE:
+ // set(int, byte, int) always handles these ops itself
+ set(pos, op, ((Integer)arg).intValue());
+ return;
+ case LDC:
+ // set(int, byte, int) always handles these opts itself
+ if(arg instanceof Integer) { set(pos, op, ((Integer)arg).intValue()); return; }
+ if(arg instanceof Boolean) { set(pos, op, ((Boolean)arg).booleanValue()); return; }
+
+ if(arg instanceof Long) {
+ long l = ((Long)arg).longValue();
+ if(l == 0L) { this.op[pos] = LCONST_0; return; }
+ if(l == 1L) { this.op[pos] = LCONST_1; return; }
+ }
+
+ if(arg instanceof Long || arg instanceof Double) op = LDC2_W;
+ break;
+ case INVOKEINTERFACE: {
+ break;
+ }
+ }
+ int opdata = OP_DATA[op&0xff];
+ if((opdata&OP_CPENT_FLAG) != 0 && !(arg instanceof CPGen.Ent)) {
+ if (op==INVOKEINTERFACE) arg = cp.add(arg, true);
+ else arg = cp.add(arg);
}
+ else if((opdata&OP_VALID_FLAG) == 0)
+ throw new IllegalArgumentException("unknown bytecode");
this.op[pos] = op;
this.arg[pos] = arg;
}
+
+ /** This class represents the arguments to the TABLESWITH and LOOKUPSWITCH bytecodes
+ @see MethodGen.TSI
+ @see MethodGen.LSI
+ */
+ public static abstract class SI {
+ public final Object[] targets;
+ public Object defaultTarget;
+
+ SI(int size) { targets = new Object[size]; }
+ public void setTarget(int pos, Object val) { targets[pos] = val; }
+ public void setTarget(int pos, int val) { targets[pos] = N(val); }
+ public void setDefaultTarget(int val) { setDefaultTarget(N(val)); }
+ public void setDefaultTarget(Object o) { defaultTarget = o; }
+ public int size() { return targets.length; }
- public final void setPushConst(int pos, int n) {
- switch(n) {
- case -1: set(pos,ICONST_M1); break;
- case 0: set(pos,ICONST_0); break;
- case 1: set(pos,ICONST_1); break;
- case 2: set(pos,ICONST_2); break;
- case 3: set(pos,ICONST_3); break;
- case 4: set(pos,ICONST_4); break;
- case 5: set(pos,ICONST_5); break;
- default:
- if(n >= -128 && n <= 127) set(pos,BIPUSH,n);
- if(n >= -32767 && n <= 32767) set(pos,SIPUSH,n);
- setLDC(pos,N(n));
- break;
- }
- }
- public final void setPushConst(int pos, long l) {
- if(l==0) set(pos,LCONST_0);
- else if(l==1) set(pos,LCONST_1);
- else setLDC(pos,N(l));
+ public int getTarget(int pos) { return ((Integer)targets[pos]).intValue(); }
+ public int getDefaultTarget() { return ((Integer)defaultTarget).intValue(); }
+
+ abstract int length();
}
- public final void setPushConst(int pos, float f) {
- if(f == 1.0f) set(pos,FCONST_0);
- else if(f == 1.0f) set(pos,FCONST_1);
- else if(f == 2.0f) set(pos,FCONST_2);
- else setLDC(pos,N(f));
- }
- public final void setPushConst(int pos, double d) {
- if(d == 1.0) set(pos,DCONST_0);
- else if(d == 2.0) set(pos,DCONST_1);
- else setLDC(pos,N(d));
- }
- public final void setPushConst(int pos, Object o) {
- if(o instanceof Integer) setPushConst(pos,((Integer)o).intValue());
- else if(o instanceof Long) setPushConst(pos,((Long)o).longValue());
- else if(o instanceof Float) setPushConst(pos,((Float)o).floatValue());
- else if(o instanceof Double) setPushConst(pos,((Double)o).doubleValue());
- else setLDC(pos,o);
- }
+ /** This class represents the arguments to the TABLESWITCH bytecode */
+ public static class TSI extends SI {
+ public final int lo;
+ public final int hi;
+ public TSI(int lo, int hi) {
+ super(hi-lo+1);
+ this.lo = lo;
+ this.hi = hi;
+ }
+ public void setTargetForVal(int val, Object o) { setTarget(val-lo, o); }
+ public void setTargetForVal(int val, int n) { setTarget(val-lo, n); }
- private void setLDC(int pos, Object o) { set(pos,LDC,cp.add(o)); }
-
- public final CPGen.Ent methodRef(Type.Object c, String name, Type ret, Type[] args) {
- return methodRef(c,name,MethodGen.descriptor(ret,args));
+ int length() { return 12 + targets.length * 4; } // 4bytes/target, hi, lo, default
}
- public final CPGen.Ent methodRef(Type.Object c, String name, String descriptor) {
- return cp.add(new CPGen.MethodRef(c,new CPGen.NameAndType(name,descriptor)));
+
+ /** This class represents the arguments to the LOOKUPSWITCH bytecode */
+ public static class LSI extends SI {
+ public final int[] vals;
+ public LSI(int size) {
+ super(size);
+ this.vals = new int[size];
+ }
+ public final void setVal(int pos, int val) { vals[pos] = val; }
+
+ int length() { return 8 + targets.length * 8; } // key/val per target, default, count
}
- public final CPGen.Ent fieldRef(Type.Object c, String name, Type type) {
- return fieldRef(c,name,type.getDescriptor());
+
+ /** This class represents the arguments to byecodes that take two integer arguments. */
+ public static class Pair {
+ public int i1;
+ public int i2;
+ public Pair(int i1, int i2) { this.i1 = i1; this.i2 = i2; }
}
- public final CPGen.Ent fieldRef(Type.Object c, String name, String descriptor) {
- return cp.add(new CPGen.FieldRef(c,new CPGen.NameAndType(name,descriptor)));
- }
+ public static class Wide {
+ public final byte op;
+ public final int varNum;
+ public final int n;
+ Wide(byte op, int varNum) { this(op, varNum, 0); }
+ Wide(byte op, int varNum, int n) { this.op = op; this.varNum = varNum; this.n = n; }
+ }
+
+ /** Sets the maximum number of locals in the function to <i>maxLocals</i>. NOTE: This defaults to 0 and is automatically increased as
+ necessary when *LOAD/*STORE bytecodes are added. You do not need to call this function in most cases */
public void setMaxLocals(int maxLocals) { this.maxLocals = maxLocals; }
+ /** Sets the maxinum size of th stack for this function to <i>maxStack</i>. This defaults to 16< */
public void setMaxStack(int maxStack) { this.maxStack = maxStack; }
+ /** Computes the final bytecode for this method.
+ @exception IllegalStateException if the data for a method is in an inconsistent state (required arguments missing, etc)
+ @exception Exn if the byteocode could not be generated for any other reason (constant pool full, etc)
+ */
public void finish() {
try {
_finish();
}
}
+ private Object resolveTarget(Object arg) {
+ int target;
+ if(arg instanceof PhantomTarget) {
+ target = ((PhantomTarget)arg).getTarget();
+ if(target == -1) throw new IllegalStateException("unresolved phantom target");
+ arg = N(target);
+ } else {
+ target = ((Integer)arg).intValue();
+ }
+ if(target < 0 || target >= size)
+ throw new IllegalStateException("invalid target address");
+ return arg;
+ }
+
private void _finish() throws IOException {
- if(size == -1) return;
+ if(size == FINISHED) return;
+
+ cp.stable();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
DataOutput o = new DataOutputStream(baos);
int[] pc = new int[size];
int[] maxpc = pc;
- int p,i;
+ int p, i;
- // Pass1 - Calculate maximum pc of each bytecode
- for(i=0,p=0;i<size;i++) {
+ // Pass1 - Calculate maximum pc of each bytecode, widen some insns, resolve any unresolved jumps, etc
+ for(i=0, p=0;i<size;i++) {
byte op = this.op[i];
+ int opdata = OP_DATA[op&0xff];
+ int j;
maxpc[i] = p;
+
+ if((opdata & OP_BRANCH_FLAG)!= 0) {
+ try {
+ arg[i] = resolveTarget(arg[i]);
+ } catch(RuntimeException e) {
+ System.err.println("WARNING: Error resolving target for " + Integer.toHexString(op&0xff));
+ throw e;
+ }
+ }
+
switch(op) {
- case GOTO: p += 3; break;
- case JSR: p += 3; break;
- case NOP: if(!EMIT_NOPS) continue; /* fall though */
- default: p += 1 + opArgLength(op); break;
+ // Speical caculations
+ case GOTO:
+ case JSR: {
+ int arg = ((Integer)this.arg[i]).intValue();
+ if(arg < i && p - maxpc[arg] <= 32768) p += 3;
+ else p += 5;
+ continue;
+ }
+ case NOP:
+ if(EMIT_NOPS) p++;
+ continue;
+ case LOOKUPSWITCH:
+ case TABLESWITCH: {
+ SI si = (SI) arg[i];
+ Object[] targets = si.targets;
+ for(j=0;j<targets.length;j++) targets[j] = resolveTarget(targets[j]);
+ si.defaultTarget = resolveTarget(si.defaultTarget);
+ p += 1 + 3 + si.length(); // opcode itself, padding, data
+ if(op == LOOKUPSWITCH) { // verify sanity of lookupswitch vals
+ int[] vals = ((LSI)si).vals;
+ for(j=1;j<vals.length;j++)
+ if(vals[j] <= vals[j-1])
+ throw new IllegalStateException("out of order/duplicate lookupswitch values");
+ }
+ continue;
+ }
+ // May need widening
+ case ILOAD: case ISTORE: case LLOAD: case LSTORE: case FLOAD:
+ case FSTORE: case DLOAD: case DSTORE: case ALOAD: case ASTORE:
+ case RET: {
+ int arg = ((Integer)this.arg[i]).intValue();
+ if(arg > 255) {
+ this.op[i] = WIDE;
+ this.arg[i] = new Wide(op, arg);
+ }
+ break;
+ }
+ case IINC: {
+ Pair pair = (Pair) this.arg[i];
+ if(pair.i1 > 255 || pair.i2 < -128 || pair.i2 > 127) {
+ this.op[i] = WIDE;
+ this.arg[i] = new Wide(IINC, pair.i1, pair.i2);
+ }
+ break;
+ }
+ case LDC:
+ j = cp.getIndex((CPGen.Ent)arg[i]);
+ if(j >= 256) this.op[i] = op = LDC_W;
+ break;
+ default:
}
+ if((j = (opdata&OP_ARG_LENGTH_MASK)) == 7) throw new Error("shouldn't be here");
+ p += 1 + j;
}
+
// Pass2 - Widen instructions if they can possibly be too short
for(i=0;i<size;i++) {
switch(op[i]) {
int diff = maxpc[arg] - maxpc[i];
if(diff < -32768 || diff > 32767)
op[i] = op[i] == GOTO ? GOTO_W : JSR_W;
+ break;
}
}
}
+
// Pass3 - Calculate actual pc
- for(i=0,p=0;i<size;i++) {
+ for(i=0, p=0;i<size;i++) {
byte op = this.op[i];
pc[i] = p;
- p += op != NOP || EMIT_NOPS ? 1 + opArgLength(op) : 0;
+ switch(op) {
+ case NOP:
+ if(EMIT_NOPS) p++;
+ break;
+ case TABLESWITCH:
+ case LOOKUPSWITCH: {
+ SI si = (SI) arg[i];
+ p++; // opcode itself
+ p = (p + 3) & ~3; // padding
+ p += 4; // default
+ if(op == TABLESWITCH) p += 4 + 4 + si.size() * 4; // lo, hi, targets
+ else p += 4 + si.size() * 4 * 2; // count, key, val * targets
+ break;
+ }
+ case WIDE:
+ p += 2 + (((Wide)arg[i]).op == IINC ? 4 : 2);
+ break;
+ default: {
+ int l = OP_DATA[op&0xff] & OP_ARG_LENGTH_MASK;
+ if(l == 7) throw new Error("shouldn't be here");
+ p += 1 + l;
+ }
+ }
}
+ int codeSize = p;
+
+ if(codeSize >= 65536) throw new ClassFile.Exn("method too large in size");
o.writeShort(maxStack);
o.writeShort(maxLocals);
- o.writeInt(p);
+ o.writeInt(codeSize);
// Pass 4 - Actually write the bytecodes
for(i=0;i<size;i++) {
byte op = this.op[i];
- System.err.println("" + i + " Writing " + Integer.toHexString(op) + " at " + pc[i]);
+ int opdata = OP_DATA[op&0xff];
if(op == NOP && !EMIT_NOPS) continue;
- int argLength = opArgLength(op);
- o.writeByte(op&0xff);
- if(argLength == 0) continue;
- Object arg = this.arg[i];
- int iarg = arg instanceof Integer ? ((Integer)arg).intValue() : -1;
- int outArg = iarg;
+ o.writeByte(op);
+ int argLength = opdata & OP_ARG_LENGTH_MASK;
+
+ if(argLength == 0) continue; // skip if no args
+
+ // Write args
+ Object arg = this.arg[i];
switch(op) {
case IINC: {
- int[] pair = (int[]) arg;
- if(pair[0] > 255 || pair[1] < -128 || pair[1] > 127) throw new ClassGen.Exn("overflow of iinc arg");
- o.writeByte(pair[0]);
- o.writeByte(pair[1]);
- continue;
+ Pair pair = (Pair) arg;
+ if(pair.i1 > 255 || pair.i2 < -128 || pair.i2 > 127) throw new ClassFile.Exn("overflow of iinc arg");
+ o.writeByte(pair.i1);
+ o.writeByte(pair.i2);
+ break;
}
- case IF_ICMPLT:
- case GOTO:
- case GOTO_W:
- case JSR:
- case JSR_W:
- outArg = pc[iarg] - pc[i];
- if(outArg < -32768 || outArg > 32767) throw new ClassGen.Exn("overflow of s2 offset");
+ case TABLESWITCH:
+ case LOOKUPSWITCH: {
+ SI si = (SI) arg;
+ int mypc = pc[i];
+ for(p = pc[i]+1;(p&3)!=0;p++) o.writeByte(0);
+ o.writeInt(pc[si.getDefaultTarget()] - mypc);
+ if(op == LOOKUPSWITCH) {
+ int[] vals = ((LSI)si).vals;
+ o.writeInt(si.size());
+ for(int j=0;j<si.size();j++) {
+ o.writeInt(vals[j]);
+ o.writeInt(pc[si.getTarget(j)] - mypc);
+ }
+ } else {
+ TSI tsi = (TSI) si;
+ o.writeInt(tsi.lo);
+ o.writeInt(tsi.hi);
+ for(int j=0;j<tsi.size();j++) o.writeInt(pc[tsi.getTarget(j)] - mypc);
+ }
break;
- case INVOKESTATIC:
- case INVOKESPECIAL:
- case INVOKEVIRTUAL:
- case GETSTATIC:
- case PUTSTATIC:
- case GETFIELD:
- case PUTFIELD:
- case LDC_W:
- case LDC:
- outArg = ((CPGen.Ent)arg).index;
+ }
+ case WIDE: {
+ Wide wide = (Wide) arg;
+ o.writeByte(wide.op);
+ o.writeShort(wide.varNum);
+ if(wide.op == IINC) o.writeShort(wide.n);
+ break;
+ }
+
+ default:
+ if((opdata & OP_BRANCH_FLAG) != 0) {
+ int v = pc[((Integer)arg).intValue()] - pc[i];
+ if(argLength == 2) {
+ if(v < -32768 || v > 32767) throw new ClassFile.Exn("overflow of s2 offset");
+ o.writeShort(v);
+ } else if(argLength == 4) {
+ o.writeInt(v);
+ } else {
+ throw new Error("should never happen");
+ }
+ } else if((opdata & OP_CPENT_FLAG) != 0) {
+ int v = cp.getIndex((CPGen.Ent)arg);
+ if(argLength == 1) o.writeByte(v);
+ else if(argLength == 2) o.writeShort(v);
+ else throw new Error("should never happen");
+ } else if(argLength == 7) {
+ throw new Error("should never happen - variable length instruction not explicitly handled");
+ } else {
+ int iarg = ((Integer)arg).intValue();
+ if(argLength == 1) {
+ if(iarg < -128 || iarg >= 256) throw new ClassFile.Exn("overflow of s/u1 option");
+ o.writeByte(iarg);
+ } else if(argLength == 2) {
+ if(iarg < -32768 || iarg >= 65536) throw new ClassFile.Exn("overflow of s/u2 option");
+ o.writeShort(iarg);
+ } else {
+ throw new Error("should never happen");
+ }
+ }
break;
}
-
- if(argLength == 1) o.writeByte(outArg);
- else if(argLength == 2) o.writeShort(outArg);
- else throw new Error("should never happen");
}
- o.writeShort(0); // FIXME: Exception table
+ //if(baos.size() - 8 != codeSize) throw new Error("we didn't output what we were supposed to");
+
+ o.writeShort(exnTable.size());
+ for(Enumeration e = exnTable.keys();e.hasMoreElements();)
+ ((ExnTableEnt)exnTable.get(e.nextElement())).dump(o, pc, codeSize);
+
o.writeShort(codeAttrs.size());
codeAttrs.dump(o);
baos.close();
byte[] codeAttribute = baos.toByteArray();
- attrs.add("Code",codeAttribute);
- size = -1;
+ attrs.add("Code", codeAttribute);
+
+ baos.reset();
+ o.writeShort(thrownExceptions.size());
+ for(Enumeration e = thrownExceptions.keys();e.hasMoreElements();)
+ o.writeShort(cp.getIndex((CPGen.Ent)thrownExceptions.get(e.nextElement())));
+ attrs.add("Exceptions", baos.toByteArray());
+
+ size = capacity = FINISHED;
}
- public void dump(DataOutput o) throws IOException {
+ void dump(DataOutput o) throws IOException {
o.writeShort(flags);
- o.writeShort(nameIndex);
- o.writeShort(descriptorIndex);
+ o.writeShort(cp.getUtf8Index(name));
+ o.writeShort(cp.getUtf8Index(owner.getType().method(name, ret, args).getDescriptor()));
o.writeShort(attrs.size());
attrs.dump(o);
}
- private static int opArgLength(byte op) {
+ /** Negates the IF* instruction, <i>op</i> (IF_ICMPGT -> IF_ICMPLE, IFNE -> IFEQ, etc)
+ @exception IllegalArgumentException if <i>op</i> isn't an IF* instruction */
+ public static byte negate(byte op) {
switch(op) {
- case NOP:
- case ICONST_M1:
- case ICONST_0:
- case ICONST_1:
- case ICONST_2:
- case ICONST_3:
- case ICONST_4:
- case ICONST_5:
- case LCONST_0:
- case LCONST_1:
- case FCONST_0:
- case FCONST_1:
- case FCONST_2:
- case DCONST_0:
- case DCONST_1:
- case ILOAD_0:
- case ILOAD_1:
- case ILOAD_2:
- case ILOAD_3:
- case ISTORE_0:
- case ISTORE_1:
- case ISTORE_2:
- case ISTORE_3:
- case RETURN:
- return 0;
- case LDC:
- case BIPUSH:
- case ILOAD:
- case ISTORE:
- return 1;
- case LDC_W:
- case SIPUSH:
- case GETSTATIC:
- case PUTSTATIC:
- case GETFIELD:
- case PUTFIELD:
- case INVOKESTATIC:
- case INVOKEVIRTUAL:
- case INVOKESPECIAL:
- case IINC:
- case GOTO:
- case JSR:
- case IF_ICMPLT:
- return 2;
+ case IFEQ: return IFNE;
+ case IFNE: return IFEQ;
+ case IFLT: return IFGE;
+ case IFGE: return IFLT;
+ case IFGT: return IFLE;
+ case IFLE: return IFGT;
+ case IF_ICMPEQ: return IF_ICMPNE;
+ case IF_ICMPNE: return IF_ICMPEQ;
+ case IF_ICMPLT: return IF_ICMPGE;
+ case IF_ICMPGE: return IF_ICMPLT;
+ case IF_ICMPGT: return IF_ICMPLE;
+ case IF_ICMPLE: return IF_ICMPGT;
+ case IF_ACMPEQ: return IF_ACMPNE;
+ case IF_ACMPNE: return IF_ACMPEQ;
+
default:
- throw new ClassGen.Exn("unknown bytecode " + Integer.toHexString(op&0xff));
+ throw new IllegalArgumentException("Can't negate " + Integer.toHexString(op));
}
}
-
+
+ /** Class that represents a target that isn't currently know. The target MUST be set with setTarget() before the classfile is written.
+ This class is more or less a mutable integer */
+ public static class PhantomTarget {
+ private int target = -1;
+ public void setTarget(int target) { this.target = target; }
+ public int getTarget() { return target; }
+ }
+
private static Integer N(int n) { return new Integer(n); }
private static Long N(long n) { return new Long(n); }
private static Float N(float f) { return new Float(f); }
private static Double N(double d) { return new Double(d); }
private static int max(int a, int b) { return a > b ? a : b; }
+
+ private static final int OP_BRANCH_FLAG = 1<<3;
+ private static final int OP_CPENT_FLAG = 1<<4;
+ private static final int OP_VALID_FLAG = 1<<5;
+ private static final int OP_ARG_LENGTH_MASK = 7;
+ private static final boolean OP_VALID(byte op) { return (OP_DATA[op&0xff] & OP_VALID_FLAG) != 0; }
+ private static final int OP_ARG_LENGTH(byte op) { return (OP_DATA[op&0xff]&OP_ARG_LENGTH_MASK); }
+ private static final boolean OP_CPENT(byte op) { return (OP_DATA[op&0xff]&OP_CPENT_FLAG) != 0; }
+ private static final boolean OP_BRANCH(byte op) { return (OP_DATA[op&0xff]&OP_BRANCH_FLAG ) != 0; }
+
+ // Run perl -x src/org/ibex/classgen/CGConst.java to generate this
+ private static final byte[] OP_DATA = {
+ 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+ 0x21, 0x22, 0x31, 0x32, 0x32, 0x21, 0x21, 0x21, 0x21, 0x21, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+ 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+ 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x21, 0x21, 0x21, 0x21, 0x21, 0x20, 0x20, 0x20, 0x20, 0x20,
+ 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+ 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+ 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+ 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+ 0x20, 0x20, 0x20, 0x20, 0x22, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+ 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+ 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x21, 0x27, 0x27, 0x20, 0x20, 0x20, 0x20,
+ 0x20, 0x20, 0x32, 0x32, 0x32, 0x32, 0x32, 0x32, 0x32, 0x32, 0x01, 0x32, 0x21, 0x32, 0x20, 0x20,
+ 0x32, 0x32, 0x20, 0x20, 0x27, 0x23, 0x2a, 0x2a, 0x2c, 0x2c, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+ 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+ 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+ 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01
+ };
}
projects / org.ibex.classgen.git / blobdiff