1 package org.ibex.classgen;
6 * a highly streamlined SSA-form intermediate representation of a
7 * sequence of JVM instructions; all stack manipulation is factored
10 public class JSSA extends MethodGen implements CGConst {
12 // Constructor //////////////////////////////////////////////////////////////////////////////
14 public JSSA(Type.Class c, DataInput in, ConstantPool cp) throws IOException {
16 local = new Expr[maxLocals];
17 stack = new Expr[maxStack];
18 for(int i=0; i<this.method.getNumArgs(); i++)
19 local[i] = new Argument("arg"+i, this.method.getArgType(i));
20 for(int i=0; i<size(); i++) {
22 Object arg = getArg(i);
23 Object o = addOp(op, arg);
31 public void debugBodyToString(StringBuffer sb) {
32 StringBuffer sb0 = new StringBuffer();
33 super.debugBodyToString(sb0);
34 StringTokenizer st = new StringTokenizer(sb0.toString(), "\n");
35 String[] lines = new String[st.countTokens()];
36 for(int i=0; i<lines.length; i++) lines[i] = st.nextToken();
37 for(int j=0; j<ofs[0]; j++) {
38 String s = " /* " + lines[j].trim();
39 while(s.length() < 50) s += " ";
44 for(int i=0; i<numOps; i++) {
45 String s = " /* " + lines[ofs[i]].trim();
46 while(s.length() < 50) s += " ";
48 s += ops[i].toString();
51 for(int j=ofs[i]+1; j<(i==numOps-1?size():ofs[i+1]); j++) {
52 s = " /* " + lines[j].trim();
53 while(s.length() < 50) s += " ";
61 private Object[] ops = new Object[65535];
62 private int[] ofs = new int[65535];
63 private int numOps = 0;
65 // Instance Data; used ONLY during constructor; then thrown away /////////////////////////////////////////////////
67 /** this models the JVM locals; it is only used for unwinding stack-ops into an SSA-tree, then thrown away */
68 private final Expr[] local;
70 /** this models the JVM stack; it is only used for unwinding stack-ops into an SSA-tree, then thrown away */
71 private final Expr[] stack;
73 /** JVM stack pointer */
76 private Expr push(Expr e) { return stack[sp++] = e; }
77 private Expr pop() { return stack[--sp]; }
80 // SSA-node classes /////////////////////////////////////////////////////////////////////////////////////////
82 public final Expr VOID_EXPR = new Expr() {
83 public Type getType() { return Type.VOID; }
86 /** an purely imperative operation which does not generate data */
87 public abstract class Op {
88 //public abstract Op[] predecessors(); // not implemented yet
89 //public abstract Op[] successors(); // not implemented yet
90 public String toString() { return name(); }
92 String name = this.getClass().getName();
93 if (name.indexOf('$') != -1) name = name.substring(name.lastIndexOf('$')+1);
94 if (name.indexOf('.') != -1) name = name.substring(name.lastIndexOf('.')+1);
99 /** an operation which generates data */
100 public abstract class Expr extends Op {
101 //public abstract Expr[] contributors(); // not implemented yet
102 //public abstract Expr[] dependents(); // not implemented yet
104 /** every JSSA.Expr either remembers its type _OR_ knows how to figure it out (the latter is preferred to eliminate
105 * redundant information that could possibly "disagree" with itself -- this happened a LOT in Soot) */
106 public abstract Type getType();
110 * A "nondeterministic merge" -- for example when the first instruction in a loop reads from a local which could have been
111 * written to either by some instruction at the end of the previous iteration of the loop or by some instruction before
112 * the loop (on the first iteration).
114 public class Phi extends Expr {
115 private final Expr[] inputs;
116 public Phi(Expr[] inputs) {
117 this.inputs = new Expr[inputs.length];
118 System.arraycopy(inputs, 0, this.inputs, 0, inputs.length);
120 public Type getType() {
122 Type t = inputs[0].getType();
124 // FIXME: actually this should check type-unifiability... fe, the "type of null" unifies with any Type.Ref
125 for(int i=1; i<inputs.length; i++)
126 if (inputs[i].getType() != t)
127 throw new Error("Phi node with disagreeing types! Crisis!");
132 public class Argument extends Expr {
133 public final String name;
135 public Argument(String name, Type t) { this.name = name; this.t = t; }
136 public String toString() { return name; }
137 public Type getType() { return t; }
140 // Binary Operations //////////////////////////////////////////////////////////////////////////////
142 public abstract class BinExpr extends Expr {
143 public final Expr e1;
144 public final Expr e2;
145 public BinExpr(Expr e1, Expr e2) { this.e1 = e1; this.e2 = e2; }
146 public String toString() {
147 return name() + "("+e1+", "+e2+")";
151 public class Comparison extends BinExpr {
152 public Comparison(Expr e1, Expr e2) { super(e1, e2); }
153 public Type getType() { return Type.BOOLEAN; }
155 public class Gt extends Comparison { public Gt(Expr e1, Expr e2) { super(e1, e2); } }
156 public class Lt extends Comparison { public Lt(Expr e1, Expr e2) { super(e1, e2); } }
157 public class Eq extends Comparison { public Eq(Expr e1, Expr e2) { super(e1, e2); } }
158 public class Not extends Expr {
160 public Not(Expr e) { this.e = e; }
161 public Type getType() { return Type.BOOLEAN; }
164 // Math Operations //////////////////////////////////////////////////////////////////////////////
166 public class Math extends BinExpr {
167 private final String show;
168 public Math(Expr e1, Expr e2, String show) { super(e2, e1); this.show = show; }
169 public String toString() { return e1+" "+show+" "+e2; }
170 public Type getType() {
171 Type t = e1.getType();
172 if (t != e2.getType()) throw new Error("types disagree");
176 public class Add extends Math { public Add(Expr e, Expr e2) { super(e, e2, "+"); } }
177 public class Sub extends Math { public Sub(Expr e, Expr e2) { super(e, e2, "-"); } }
178 public class Mul extends Math { public Mul(Expr e, Expr e2) { super(e, e2, "*"); } }
179 public class Rem extends Math { public Rem(Expr e, Expr e2) { super(e, e2, "%"); } }
180 //public class Neg extends Math { public Neg(Expr e) { super(e, "-"); } }
181 public class Div extends Math { public Div(Expr e, Expr e2) { super(e, e2, "/"); } }
182 public class Shl extends Math { public Shl(Expr e, Expr e2) { super(e, e2, "<<"); } }
183 public class Shr extends Math { public Shr(Expr e, Expr e2) { super(e, e2, ">>"); } }
184 public class Ushr extends Math { public Ushr(Expr e, Expr e2) { super(e, e2, ">>>"); } }
185 public class And extends Math { public And(Expr e, Expr e2) { super(e, e2, "&"); } }
186 public class Or extends Math { public Or(Expr e, Expr e2) { super(e, e2, "|"); } }
187 public class Xor extends Math { public Xor(Expr e, Expr e2) { super(e, e2, "^"); } }
189 // Other operations //////////////////////////////////////////////////////////////////////////////
191 public class Cast extends Expr {
194 public Cast(Expr e, Type t) {
195 if(e.getType().isRef() != t.isRef()) throw new IllegalArgumentException("invalid cast");
196 // FEATURE: Check that one is a subclass of the other if it is a ref
200 public Type getType() { return t; }
203 public class InstanceOf extends Expr {
206 public InstanceOf(Expr e, Type.Ref t) {
207 if(!e.getType().isRef()) throw new IllegalArgumentException("can't do an instanceof check on a non-ref");
211 public Type getType() { return Type.BOOLEAN; }
214 public class Throw extends Op {
216 public Throw(Expr e) {
217 if(!e.getType().isRef()) throw new IllegalArgumentException("can't throw a non ref");
218 // FEATURE: CHeck that it is a subclass of Throwable
223 public class Branch extends Op {
224 public Branch(Expr condition, Object destination) { }
225 public Branch(Label destination) { }
226 public Branch(MethodGen.Switch s) { }
229 public class Goto extends Branch { }
230 public class RET extends Branch { }
231 public class JSR extends Branch { public JSR(Label l) { super(l); } }
232 public class If extends Branch { }
234 /** represents a "returnaddr" pushed onto the stack */
235 public class Label extends Expr {
237 public Type getType() { throw new Error("attempted to call getType() on a Label"); }
238 public Label(Op op) { this.op = op; }
239 public Label(int i) { this.op = null; /* FIXME */ }
242 public class New extends Expr {
243 public final Type.Class t;
244 public Type getType() { return t; }
245 public New(Type.Class t) { this.t = t; }
248 public class NewArray extends Expr {
249 public final Type.Array t;
250 public final Expr[] dims;
251 public NewArray(Type.Array t, Expr[] dims) { this.t = t; this.dims = dims; }
252 public NewArray(Type.Array t, Expr dim) { this(t,new Expr[]{dim}); }
253 public Type getType() { return t; }
256 // FEATURE: Array stuff
258 public class Return extends Op {
260 public Return() { this(VOID_EXPR); }
261 public Return(Expr e) { this.e = e; }
262 public String toString() { return e.getType() == Type.VOID ? "return" : ("return "+e.toString()); }
265 /** GETFIELD and GETSTATIC */
266 public class Get extends Expr {
267 final Type.Class.Field f;
269 public Type getType() { return f.getType(); }
270 public Get(Type.Class.Field f) { this(f, null); }
271 public Get(Type.Class.Field f, Expr e) { this.f = f; this.e = e; }
272 public String toString() {
276 : f.getDeclaringClass() == JSSA.this.method.getDeclaringClass()
282 /** PUTFIELD and PUTSTATIC */
283 public class Put extends Op {
284 final Type.Class.Field f;
287 public Put(Type.Class.Field f, Expr v) { this(f, v, null); }
288 public Put(Type.Class.Field f, Expr v, Expr e) { this.f = f; this.v = v; this.e = e; }
289 public String toString() {
293 : f.getDeclaringClass() == JSSA.this.method.getDeclaringClass()
295 : f.toString()) + " = " + v;
299 public class ArrayPut extends Op {
301 public ArrayPut(Expr e, Expr i, Expr v) { this.e = e; this.i = i; this.v = v; }
304 public class ArrayGet extends Expr {
306 public ArrayGet(Expr e, Expr i) { this.e = e; this.i = i; }
307 public Type getType() { return e.getType().asArray().getElementType(); }
310 public class ArrayLength extends Expr {
312 public ArrayLength(Expr e) { this.e = e; }
313 public Type getType() { return Type.INT; }
316 public abstract class Invoke extends Expr {
317 public final Expr[] arguments;
318 public final Type.Class.Method method;
319 protected Invoke(Type.Class.Method m, Expr[] a) { this.arguments = a; this.method = m; }
321 public Type getType() { return method.getReturnType(); }
322 protected void args(StringBuffer sb) {
324 for(int i=0; i<arguments.length; i++) {
325 if (i>0) sb.append(", ");
326 sb.append(arguments[i]+"");
331 public String toString() {
332 StringBuffer sb = new StringBuffer();
333 sb.append(method.getDeclaringClass() == JSSA.this.method.getDeclaringClass()
335 : (method.getDeclaringClass() + "." + method.name));
337 return sb.toString();
340 public class InvokeStatic extends Invoke { public InvokeStatic(Type.Class.Method m, Expr[] a) { super(m,a); } }
341 public class InvokeSpecial extends InvokeVirtual {
342 public InvokeSpecial(Type.Class.Method m, Expr[] a, Expr e) { super(m,a,e); }
343 public String toString() {
344 StringBuffer sb = new StringBuffer();
345 sb.append(method.name.equals("<init>") ? "super" : method.name);
347 return sb.toString();
350 public class InvokeInterface extends InvokeVirtual{public InvokeInterface(Type.Class.Method m, Expr[] a, Expr e){super(m,a,e);}}
351 public class InvokeVirtual extends Invoke {
352 public final Expr instance;
353 public InvokeVirtual(Type.Class.Method m, Expr[] a, Expr e) { super(m, a); instance = e; }
354 public String toString() {
355 StringBuffer sb = new StringBuffer();
356 sb.append(method.name);
358 return sb.toString();
362 public class Constant extends Expr {
363 private final Object o;
364 public Constant(int i) { this(new Integer(i)); }
365 public Constant(Object o) { this.o = o; }
366 public String toString() { return o.toString(); }
367 public Type getType() {
368 if (o instanceof Byte) return Type.BYTE;
369 if (o instanceof Short) return Type.SHORT;
370 if (o instanceof Character) return Type.CHAR;
371 if (o instanceof Boolean) return Type.BOOLEAN;
372 if (o instanceof Long) return Type.LONG;
373 if (o instanceof Double) return Type.DOUBLE;
374 if (o instanceof Float) return Type.FLOAT;
375 if (o instanceof ConstantPool.Ent) throw new Error("unimplemented");
376 throw new Error("this should not happen");
381 // Implementation //////////////////////////////////////////////////////////////////////////////
383 private Object addOp(int op, Object arg) {
387 MethodGen.Wide w = (MethodGen.Wide)arg;
394 MethodGen.Pair p = (MethodGen.Pair)arg;
401 case NOP: return null;
403 // Stack manipulations //////////////////////////////////////////////////////////////////////////////
405 case ACONST_NULL: return stack[sp++] = new Constant(null);
406 case ICONST_M1: return stack[sp++] = new Constant(-1);
407 case ICONST_0: case LCONST_0: case FCONST_0: case DCONST_0: push(new Constant(0)); return null;
408 case ICONST_1: case LCONST_1: case FCONST_1: case DCONST_1: push(new Constant(1)); return null;
409 case ICONST_2: case FCONST_2: push(new Constant(2)); return null;
410 case ICONST_3: push(new Constant(3)); return null;
411 case ICONST_4: push(new Constant(4)); return null;
412 case ICONST_5: push(new Constant(5)); return null;
413 case ILOAD: case LLOAD: case FLOAD: case DLOAD: case ALOAD: return push(local[i1]);
414 case ILOAD_0: case LLOAD_0: case FLOAD_0: case DLOAD_0: case ALOAD_0: return push(local[0]);
415 case ILOAD_1: case LLOAD_1: case FLOAD_1: case DLOAD_1: case ALOAD_1: return push(local[1]);
416 case ALOAD_2: case DLOAD_2: case FLOAD_2: case LLOAD_2: case ILOAD_2: return push(local[2]);
417 case ILOAD_3: case LLOAD_3: case FLOAD_3: case DLOAD_3: case ALOAD_3: return push(local[3]);
418 case ISTORE: case LSTORE: case FSTORE: case DSTORE: case ASTORE: local[i1] = pop(); return null;
419 case ISTORE_0: case LSTORE_0: case FSTORE_0: case DSTORE_0: case ASTORE_0: local[0] = pop(); return null;
420 case ISTORE_1: case LSTORE_1: case FSTORE_1: case DSTORE_1: case ASTORE_1: local[1] = pop(); return null;
421 case ASTORE_2: case DSTORE_2: case FSTORE_2: case LSTORE_2: case ISTORE_2: local[2] = pop(); return null;
422 case ISTORE_3: case LSTORE_3: case FSTORE_3: case DSTORE_3: case ASTORE_3: local[3] = pop(); return null;
423 case POP: stack[--sp] = null;
424 case POP2: stack[--sp] = null; stack[--sp] = null; /** fixme: pops a WORD, not an item */
425 case DUP: stack[sp] = stack[sp-1]; sp++;
426 case DUP2: stack[sp] = stack[sp-2]; stack[sp+1] = stack[sp-1]; sp+=2;
428 // Conversions //////////////////////////////////////////////////////////////////////////////
430 // coercions are added as-needed when converting from JSSA back to bytecode, so we can
431 // simply discard them here (assuming the bytecode we're reading in was valid in the first place)
433 case I2L: case F2L: case D2L: push(new Cast(pop(), Type.LONG)); return null;
434 case I2F: case L2F: case D2F: push(new Cast(pop(), Type.FLOAT)); return null;
435 case I2D: case L2D: case F2D: push(new Cast(pop(), Type.DOUBLE)); return null;
436 case L2I: case F2I: case D2I: push(new Cast(pop(), Type.INT)); return null;
437 case I2B: push(new Cast(pop(), Type.BYTE)); return null;
438 case I2C: push(new Cast(pop(), Type.CHAR)); return null;
439 case I2S: push(new Cast(pop(), Type.SHORT)); return null;
440 case SWAP: { Expr e1 = pop(), e2 = pop(); push(e2); push(e1); return null; }
442 // Math //////////////////////////////////////////////////////////////////////////////
444 case IADD: case LADD: case FADD: case DADD: push(new Add(pop(), pop())); return null;
445 case ISUB: case LSUB: case FSUB: case DSUB: push(new Sub(pop(), pop())); return null;
446 case IMUL: case LMUL: case FMUL: case DMUL: push(new Mul(pop(), pop())); return null;
447 case IREM: case LREM: case FREM: case DREM: push(new Rem(pop(), pop())); return null;
448 //case INEG: case LNEG: case FNEG: case DNEG: push(new Neg(pop())); return null;
449 case IDIV: case LDIV: case FDIV: case DDIV: push(new Div(pop(), pop())); return null;
450 case ISHL: case LSHL: push(new Shl(pop(), pop())); return null;
451 case ISHR: case LSHR: push(new Shr(pop(), pop())); return null;
452 case IUSHR: case LUSHR: push(new Ushr(pop(), pop())); return null;
453 case IAND: case LAND: push(new And(pop(), pop())); return null;
454 case IOR: case LOR: push(new Or(pop(), pop())); return null;
455 case IXOR: case LXOR: push(new Xor(pop(), pop())); return null;
456 case IINC: return local[i1] = new Add(local[i1], new Constant(i2));
458 // Control and branching //////////////////////////////////////////////////////////////////////////////
460 case IFNULL: return new Branch(new Eq(pop(), new Constant(null)), new Label(i1));
461 case IFNONNULL: return new Branch(new Not(new Eq(pop(),new Constant(null))),new Label(i1));
462 case IFEQ: return new Branch( new Eq(new Constant(0), pop()), arg);
463 case IFNE: return new Branch(new Not(new Eq(new Constant(0), pop())), arg);
464 case IFLT: return new Branch( new Lt(new Constant(0), pop()), arg);
465 case IFGE: return new Branch(new Not(new Lt(new Constant(0), pop())), arg);
466 case IFGT: return new Branch( new Gt(new Constant(0), pop()), arg);
467 case IFLE: return new Branch(new Not(new Gt(new Constant(0), pop())), arg);
468 case IF_ICMPEQ: return new Branch( new Eq(pop(), pop()), arg);
469 case IF_ICMPNE: return new Branch(new Not(new Eq(pop(), pop())), arg);
470 case IF_ICMPLT: return new Branch( new Lt(pop(), pop()), arg);
471 case IF_ICMPGE: return new Branch(new Not(new Lt(pop(), pop())), arg);
472 case IF_ICMPGT: return new Branch( new Gt(pop(), pop()), arg);
473 case IF_ICMPLE: return new Branch(new Not(new Gt(pop(), pop())), arg);
474 case IF_ACMPEQ: return new Branch( new Eq(pop(), pop()), arg);
475 case IF_ACMPNE: return new Branch(new Not(new Eq(pop(), pop())), arg);
476 case ATHROW: return new Throw(pop());
477 case GOTO: return new Branch(new Label(i1));
478 case JSR: return new JSR(new Label(i1));
479 case RET: return new RET();
480 case RETURN: return new Return();
481 case IRETURN: case LRETURN: case FRETURN: case DRETURN: case ARETURN:
482 return new Return(pop());
484 // Array manipulations //////////////////////////////////////////////////////////////////////////////
486 case IALOAD: case LALOAD: case FALOAD: case DALOAD: case AALOAD:
487 case BALOAD: case CALOAD: case SALOAD: push(new ArrayGet(pop(), pop())); return null;
488 case IASTORE: case LASTORE: case FASTORE: case DASTORE: case AASTORE:
489 case BASTORE: case CASTORE: case SASTORE: return new ArrayPut(pop(), pop(), pop());
491 // Invocation //////////////////////////////////////////////////////////////////////////////
493 case INVOKEVIRTUAL: case INVOKESPECIAL: case INVOKESTATIC: case INVOKEINTERFACE: {
494 Type.Class.Method method = (Type.Class.Method)arg;
495 Expr args[] = new Expr[method.getNumArgs()];
496 for(int i=0; i<args.length; i++) args[args.length-i-1] = pop();
498 case INVOKEVIRTUAL: return push(new InvokeVirtual(method, args, pop()));
499 case INVOKEINTERFACE: return push(new InvokeInterface(method, args, pop()));
500 case INVOKESPECIAL: return push(new InvokeSpecial(method, args, pop()));
501 case INVOKESTATIC: return push(new InvokeStatic(method, args));
505 // Field Access //////////////////////////////////////////////////////////////////////////////
507 case GETSTATIC: push(new Get((Type.Class.Field)arg, null)); return null;
508 case PUTSTATIC: return new Put((Type.Class.Field)arg, pop(), null);
509 case GETFIELD: push(new Get((Type.Class.Field)arg, pop())); return null;
510 case PUTFIELD: return new Put((Type.Class.Field)arg, pop(), pop());
512 // Allocation //////////////////////////////////////////////////////////////////////////////
514 case NEW: push(new New((Type.Class)arg)); return null;
517 switch(((Integer)arg).intValue()) {
518 case 4: base = Type.BOOLEAN; break;
519 case 5: base = Type.CHAR; break;
520 case 6: base = Type.FLOAT; break;
521 case 7: base = Type.DOUBLE; break;
522 case 8: base = Type.BYTE; break;
523 case 9: base = Type.SHORT; break;
524 case 10: base = Type.INT; break;
525 case 11: base = Type.LONG; break;
526 default: throw new IllegalStateException("invalid array type");
528 push(new NewArray(base.makeArray(),pop()));
531 case ANEWARRAY: push(new NewArray(((Type.Ref)arg).makeArray(), pop())); return null;
532 case MULTIANEWARRAY: {
533 MethodGen.MultiANewArray mana = (MethodGen.MultiANewArray) arg;
534 Expr[] dims = new Expr[mana.dims];
535 for(int i=0;i<dims.length;i++) dims[i] = pop();
536 push(new NewArray(mana.type, dims));
539 case ARRAYLENGTH: push(new ArrayLength(pop())); return null;
541 // Runtime Type information //////////////////////////////////////////////////////////////////////////////
543 case CHECKCAST: push(new Cast(pop(), (Type.Ref)arg)); return null;
544 case INSTANCEOF: push(new InstanceOf(pop(), (Type.Ref)arg)); return null;
546 case LDC: case LDC_W: case LDC2_W: push(new Constant(arg)); return null;
548 case BIPUSH: push(new Constant(i1)); // FIXME return null;
549 case SIPUSH: push(new Constant(i1)); // FIXME return null;
551 case TABLESWITCH: new Branch((MethodGen.Switch)arg);
552 case LOOKUPSWITCH: new Branch((MethodGen.Switch)arg);
555 case MONITORENTER: Op.monitorEnter(pop());
556 case MONITOREXIT: Op.monitorExit(pop());
559 case DUP_X1: throw new Error("unimplemented");
560 case DUP_X2: throw new Error("unimplemented");
561 case DUP2_X1: throw new Error("unimplemented");
562 case DUP2_X2: throw new Error("unimplemented");
563 case LCMP: throw new Error("unimplemented");
564 case FCMPL: throw new Error("unimplemented");
565 case FCMPG: throw new Error("unimplemented");
566 case DCMPL: throw new Error("unimplemented");
567 case DCMPG: throw new Error("unimplemented");
568 case GOTO_W: throw new Error("unimplemented");
569 case JSR_W: throw new Error("unimplemented");
570 default: throw new Error("unhandled");
574 public static void main(String[] args) throws Exception {
575 InputStream is = Class.forName(args[0]).getClassLoader().getResourceAsStream(args[0].replace('.', '/')+".class");
576 System.out.println(new ClassFile(new DataInputStream(is), true).toString());