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 for(int i=0; i<this.method.getNumArgs(); i++)
17 local[i] = new Argument("arg"+i, this.method.getArgType(i));
18 for(int i=0; i<size(); i++) {
20 Object arg = getArg(i);
21 Object o = addOp(op, arg);
29 public void debugBodyToString(StringBuffer sb) {
30 StringBuffer sb0 = new StringBuffer();
31 super.debugBodyToString(sb0);
32 StringTokenizer st = new StringTokenizer(sb0.toString(), "\n");
33 String[] lines = new String[st.countTokens()];
34 for(int i=0; i<lines.length; i++) lines[i] = st.nextToken();
35 for(int j=0; j<ofs[0]; j++) {
36 String s = " /* " + lines[j].trim();
37 while(s.length() < 50) s += " ";
42 for(int i=0; i<numOps; i++) {
43 String s = " /* " + lines[ofs[i]].trim();
44 while(s.length() < 50) s += " ";
46 s += ops[i].toString();
49 for(int j=ofs[i]+1; j<(i==numOps-1?size():ofs[i+1]); j++) {
50 s = " /* " + lines[j].trim();
51 while(s.length() < 50) s += " ";
59 private Object[] ops = new Object[65535];
60 private int[] ofs = new int[65535];
61 private int numOps = 0;
63 // Instance Data; used ONLY during constructor; then thrown away /////////////////////////////////////////////////
65 /** this models the JVM locals; it is only used for unwinding stack-ops into an SSA-tree, then thrown away */
66 private Expr[] local = new Expr[6];
68 /** this models the JVM stack; it is only used for unwinding stack-ops into an SSA-tree, then thrown away */
69 private Expr[] stack = new Expr[65535];
71 /** JVM stack pointer */
74 private Expr push(Expr e) { return stack[sp++] = e; }
75 private Expr pop() { return stack[--sp]; }
78 // SSA-node classes /////////////////////////////////////////////////////////////////////////////////////////
80 /** an purely imperative operation which does not generate data */
81 public abstract class Op {
82 //public abstract Op[] predecessors(); // not implemented yet
83 //public abstract Op[] successors(); // not implemented yet
84 public String toString() { return name(); }
86 String name = this.getClass().getName();
87 if (name.indexOf('$') != -1) name = name.substring(name.lastIndexOf('$')+1);
88 if (name.indexOf('.') != -1) name = name.substring(name.lastIndexOf('.')+1);
93 /** an operation which generates data */
94 public abstract class Expr extends Op {
95 //public abstract Expr[] contributors(); // not implemented yet
96 //public abstract Expr[] dependents(); // not implemented yet
98 /** every JSSA.Expr either remembers its type _OR_ knows how to figure it out (the latter is preferred to eliminate
99 * redundant information that could possibly "disagree" with itself -- this happened a LOT in Soot) */
100 public abstract Type getType();
104 * A "nondeterministic merge" -- for example when the first instruction in a loop reads from a local which could have been
105 * written to either by some instruction at the end of the previous iteration of the loop or by some instruction before
106 * the loop (on the first iteration).
108 public class Phi extends Expr {
109 private final Expr[] inputs;
110 public Phi(Expr[] inputs) {
111 this.inputs = new Expr[inputs.length];
112 System.arraycopy(inputs, 0, this.inputs, 0, inputs.length);
114 public Type getType() {
116 Type t = inputs[0].getType();
118 // FIXME: actually this should check type-unifiability... fe, the "type of null" unifies with any Type.Ref
119 for(int i=1; i<inputs.length; i++)
120 if (inputs[i].getType() != t)
121 throw new Error("Phi node with disagreeing types! Crisis!");
126 public class Argument extends Expr {
127 public final String name;
129 public Argument(String name, Type t) { this.name = name; this.t = t; }
130 public String toString() { return name; }
131 public Type getType() { return t; }
134 // Binary Operations //////////////////////////////////////////////////////////////////////////////
136 public abstract class BinExpr extends Expr {
137 public final Expr e1;
138 public final Expr e2;
139 public BinExpr(Expr e1, Expr e2) { this.e1 = e1; this.e2 = e2; }
140 public String toString() {
141 return name() + "("+e1+", "+e2+")";
145 public class Comparison extends BinExpr {
146 public Comparison(Expr e1, Expr e2) { super(e1, e2); }
147 public Type getType() { return Type.BOOLEAN; }
149 public class Gt extends Comparison { public Gt(Expr e1, Expr e2) { super(e1, e2); } }
150 public class Lt extends Comparison { public Lt(Expr e1, Expr e2) { super(e1, e2); } }
151 public class Eq extends Comparison { public Eq(Expr e1, Expr e2) { super(e1, e2); } }
152 public class Not extends Expr {
154 public Not(Expr e) { this.e = e; }
155 public Type getType() { return Type.BOOLEAN; }
158 // Math Operations //////////////////////////////////////////////////////////////////////////////
160 public class Math extends BinExpr {
161 private final String show;
162 public Math(Expr e1, Expr e2, String show) { super(e2, e1); this.show = show; }
163 public String toString() { return e1+" "+show+" "+e2; }
164 public Type getType() {
165 Type t = e1.getType();
166 if (t != e2.getType()) throw new Error("types disagree");
170 public class Add extends Math { public Add(Expr e, Expr e2) { super(e, e2, "+"); } }
171 public class Sub extends Math { public Sub(Expr e, Expr e2) { super(e, e2, "-"); } }
172 public class Mul extends Math { public Mul(Expr e, Expr e2) { super(e, e2, "*"); } }
173 public class Rem extends Math { public Rem(Expr e, Expr e2) { super(e, e2, "%"); } }
174 //public class Neg extends Math { public Neg(Expr e) { super(e, "-"); } }
175 public class Div extends Math { public Div(Expr e, Expr e2) { super(e, e2, "/"); } }
176 public class Shl extends Math { public Shl(Expr e, Expr e2) { super(e, e2, "<<"); } }
177 public class Shr extends Math { public Shr(Expr e, Expr e2) { super(e, e2, ">>"); } }
178 public class Ushr extends Math { public Ushr(Expr e, Expr e2) { super(e, e2, ">>>"); } }
179 public class And extends Math { public And(Expr e, Expr e2) { super(e, e2, "&"); } }
180 public class Or extends Math { public Or(Expr e, Expr e2) { super(e, e2, "|"); } }
181 public class Xor extends Math { public Xor(Expr e, Expr e2) { super(e, e2, "^"); } }
183 // Other operations //////////////////////////////////////////////////////////////////////////////
185 public class Cast extends Expr {
188 public Cast(Expr e, Type t) { this.e = e; this.t = t; }
189 public Type getType() { return t; }
192 public class InstanceOf extends Expr {
195 public InstanceOf(Expr e, Type t) { this.e = e; this.t = t; }
196 public Type getType() { return Type.BOOLEAN; }
199 public class Throw extends Op {
201 public Throw(Expr e) { this.e = e; }
204 public class Branch extends Op {
205 public Branch(Expr condition, Object destination) { }
206 public Branch(Label destination) { }
207 public Branch(MethodGen.Switch s) { }
210 public class Goto extends Branch { }
211 public class RET extends Branch { }
212 public class JSR extends Branch { public JSR(Label l) { super(l); } }
213 public class If extends Branch { }
215 /** represents a "returnaddr" pushed onto the stack */
216 public class Label extends Expr {
218 public Type getType() { throw new Error("attempted to call getType() on a Label"); }
219 public Label(Op op) { this.op = op; }
220 public Label(int i) { this.op = null; /* FIXME */ }
223 public class Allocate extends Expr {
225 public Type getType() { return t; }
226 public Allocate(Type t) { this.t = t; }
227 public Allocate(Type.Array t, Expr e) { this.t = t; }
230 public class Return extends Op {
232 public Return() { this(null); }
233 public Return(Expr e) { this.e = e; }
234 public String toString() { return e==null?"return":("return "+e.toString()); }
237 /** GETFIELD and GETSTATIC */
238 public class Get extends Expr {
239 final Type.Class.Field f;
241 public Type getType() { return f.getType(); }
242 public Get(Type.Class.Field f) { this(f, null); }
243 public Get(Type.Class.Field f, Expr e) { this.f = f; this.e = e; }
244 public String toString() {
248 : f.getDeclaringClass() == JSSA.this.method.getDeclaringClass()
254 /** PUTFIELD and PUTSTATIC */
255 public class Put extends Op {
256 final Type.Class.Field f;
259 public Put(Type.Class.Field f, Expr v) { this(f, v, null); }
260 public Put(Type.Class.Field f, Expr v, Expr e) { this.f = f; this.v = v; this.e = e; }
261 public String toString() {
265 : f.getDeclaringClass() == JSSA.this.method.getDeclaringClass()
267 : f.toString()) + " = " + v;
271 public class ArrayPut extends Op {
273 public ArrayPut(Expr e, Expr i, Expr v) { this.e = e; this.i = i; this.v = v; }
276 public class ArrayGet extends Expr {
278 public ArrayGet(Expr e, Expr i) { this.e = e; this.i = i; }
279 public Type getType() { return e.getType().asArray().getElementType(); }
282 public class ArrayLength extends Expr {
284 public ArrayLength(Expr e) { this.e = e; }
285 public Type getType() { return Type.INT; }
288 public abstract class Invoke extends Expr {
289 public final Expr[] arguments;
290 public final Type.Class.Method method;
291 protected Invoke(Type.Class.Method m, Expr[] a) { this.arguments = a; this.method = m; }
293 public Type getType() { return method.getReturnType(); }
294 protected void args(StringBuffer sb) {
296 for(int i=0; i<arguments.length; i++) {
297 if (i>0) sb.append(", ");
298 sb.append(arguments[i]+"");
303 public String toString() {
304 StringBuffer sb = new StringBuffer();
305 sb.append(method.getDeclaringClass() == JSSA.this.method.getDeclaringClass()
307 : (method.getDeclaringClass() + "." + method.name));
309 return sb.toString();
312 public class InvokeStatic extends Invoke { public InvokeStatic(Type.Class.Method m, Expr[] a) { super(m,a); } }
313 public class InvokeSpecial extends InvokeVirtual {
314 public InvokeSpecial(Type.Class.Method m, Expr[] a, Expr e) { super(m,a,e); }
315 public String toString() {
316 StringBuffer sb = new StringBuffer();
317 sb.append(method.name.equals("<init>") ? "super" : method.name);
319 return sb.toString();
322 public class InvokeInterface extends InvokeVirtual{public InvokeInterface(Type.Class.Method m, Expr[] a, Expr e){super(m,a,e);}}
323 public class InvokeVirtual extends Invoke {
324 public final Expr instance;
325 public InvokeVirtual(Type.Class.Method m, Expr[] a, Expr e) { super(m, a); instance = e; }
326 public String toString() {
327 StringBuffer sb = new StringBuffer();
328 sb.append(method.name);
330 return sb.toString();
334 public class Constant extends Expr {
335 private final Object o;
336 public Constant(int i) { this(new Integer(i)); }
337 public Constant(Object o) { this.o = o; }
338 public String toString() { return o.toString(); }
339 public Type getType() {
340 if (o instanceof Byte) return Type.BYTE;
341 if (o instanceof Short) return Type.SHORT;
342 if (o instanceof Character) return Type.CHAR;
343 if (o instanceof Boolean) return Type.BOOLEAN;
344 if (o instanceof Long) return Type.LONG;
345 if (o instanceof Double) return Type.DOUBLE;
346 if (o instanceof Float) return Type.FLOAT;
347 if (o instanceof ConstantPool.Ent) throw new Error("unimplemented");
348 throw new Error("this should not happen");
353 // Implementation //////////////////////////////////////////////////////////////////////////////
355 private Object addOp(int op, Object arg) {
356 Number number = null;
360 MethodGen.Wide w = (MethodGen.Wide)arg;
367 MethodGen.Pair p = (MethodGen.Pair)arg;
372 if (arg != null && arg instanceof Number) number = (Number)arg;
375 case NOP: return null;
377 // Stack manipulations //////////////////////////////////////////////////////////////////////////////
379 case ACONST_NULL: return stack[sp++] = new Constant(null);
380 case ICONST_M1: return stack[sp++] = new Constant(-1);
381 case ICONST_0: case LCONST_0: case FCONST_0: case DCONST_0: push(new Constant(0)); return null;
382 case ICONST_1: case LCONST_1: case FCONST_1: case DCONST_1: push(new Constant(1)); return null;
383 case ICONST_2: case FCONST_2: push(new Constant(2)); return null;
384 case ICONST_3: push(new Constant(3)); return null;
385 case ICONST_4: push(new Constant(4)); return null;
386 case ICONST_5: push(new Constant(5)); return null;
387 case ILOAD: case LLOAD: case FLOAD: case DLOAD: case ALOAD: return push(local[i1]);
388 case ILOAD_0: case LLOAD_0: case FLOAD_0: case DLOAD_0: case ALOAD_0: return push(local[0]);
389 case ILOAD_1: case LLOAD_1: case FLOAD_1: case DLOAD_1: case ALOAD_1: return push(local[1]);
390 case ALOAD_2: case DLOAD_2: case FLOAD_2: case LLOAD_2: case ILOAD_2: return push(local[2]);
391 case ILOAD_3: case LLOAD_3: case FLOAD_3: case DLOAD_3: case ALOAD_3: return push(local[3]);
392 case ISTORE: case LSTORE: case FSTORE: case DSTORE: case ASTORE: local[i1] = pop(); return null;
393 case ISTORE_0: case LSTORE_0: case FSTORE_0: case DSTORE_0: case ASTORE_0: local[0] = pop(); return null;
394 case ISTORE_1: case LSTORE_1: case FSTORE_1: case DSTORE_1: case ASTORE_1: local[1] = pop(); return null;
395 case ASTORE_2: case DSTORE_2: case FSTORE_2: case LSTORE_2: case ISTORE_2: local[2] = pop(); return null;
396 case ISTORE_3: case LSTORE_3: case FSTORE_3: case DSTORE_3: case ASTORE_3: local[3] = pop(); return null;
397 case POP: stack[--sp] = null;
398 case POP2: stack[--sp] = null; stack[--sp] = null; /** fixme: pops a WORD, not an item */
399 case DUP: stack[sp] = stack[sp-1]; sp++;
400 case DUP2: stack[sp] = stack[sp-2]; stack[sp+1] = stack[sp-1]; sp+=2;
402 // Conversions //////////////////////////////////////////////////////////////////////////////
404 // coercions are added as-needed when converting from JSSA back to bytecode, so we can
405 // simply discard them here (assuming the bytecode we're reading in was valid in the first place)
407 case I2L: case F2L: case D2L: push(new Cast(pop(), Type.LONG)); return null;
408 case I2F: case L2F: case D2F: push(new Cast(pop(), Type.FLOAT)); return null;
409 case I2D: case L2D: case F2D: push(new Cast(pop(), Type.DOUBLE)); return null;
410 case L2I: case F2I: case D2I: push(new Cast(pop(), Type.INT)); return null;
411 case I2B: push(new Cast(pop(), Type.BYTE)); return null;
412 case I2C: push(new Cast(pop(), Type.CHAR)); return null;
413 case I2S: push(new Cast(pop(), Type.SHORT)); return null;
414 case SWAP: { Expr e1 = pop(), e2 = pop(); push(e2); push(e1); return null; }
416 // Math //////////////////////////////////////////////////////////////////////////////
418 case IADD: case LADD: case FADD: case DADD: push(new Add(pop(), pop())); return null;
419 case ISUB: case LSUB: case FSUB: case DSUB: push(new Sub(pop(), pop())); return null;
420 case IMUL: case LMUL: case FMUL: case DMUL: push(new Mul(pop(), pop())); return null;
421 case IREM: case LREM: case FREM: case DREM: push(new Rem(pop(), pop())); return null;
422 //case INEG: case LNEG: case FNEG: case DNEG: push(new Neg(pop())); return null;
423 case IDIV: case LDIV: case FDIV: case DDIV: push(new Div(pop(), pop())); return null;
424 case ISHL: case LSHL: push(new Shl(pop(), pop())); return null;
425 case ISHR: case LSHR: push(new Shr(pop(), pop())); return null;
426 case IUSHR: case LUSHR: push(new Ushr(pop(), pop())); return null;
427 case IAND: case LAND: push(new And(pop(), pop())); return null;
428 case IOR: case LOR: push(new Or(pop(), pop())); return null;
429 case IXOR: case LXOR: push(new Xor(pop(), pop())); return null;
430 case IINC: return local[i1] = new Add(local[i1], new Constant(i2));
432 // Control and branching //////////////////////////////////////////////////////////////////////////////
434 case IFNULL: return new Branch(new Eq(pop(), new Constant(null)), new Label(i1));
435 case IFNONNULL: return new Branch(new Not(new Eq(pop(),new Constant(null))),new Label(i1));
436 case IFEQ: return new Branch( new Eq(new Constant(0), pop()), arg);
437 case IFNE: return new Branch(new Not(new Eq(new Constant(0), pop())), arg);
438 case IFLT: return new Branch( new Lt(new Constant(0), pop()), arg);
439 case IFGE: return new Branch(new Not(new Lt(new Constant(0), pop())), arg);
440 case IFGT: return new Branch( new Gt(new Constant(0), pop()), arg);
441 case IFLE: return new Branch(new Not(new Gt(new Constant(0), pop())), arg);
442 case IF_ICMPEQ: return new Branch( new Eq(pop(), pop()), arg);
443 case IF_ICMPNE: return new Branch(new Not(new Eq(pop(), pop())), arg);
444 case IF_ICMPLT: return new Branch( new Lt(pop(), pop()), arg);
445 case IF_ICMPGE: return new Branch(new Not(new Lt(pop(), pop())), arg);
446 case IF_ICMPGT: return new Branch( new Gt(pop(), pop()), arg);
447 case IF_ICMPLE: return new Branch(new Not(new Gt(pop(), pop())), arg);
448 case IF_ACMPEQ: return new Branch( new Eq(pop(), pop()), arg);
449 case IF_ACMPNE: return new Branch(new Not(new Eq(pop(), pop())), arg);
450 case ATHROW: return new Throw(pop());
451 case GOTO: return new Branch(new Label(i1));
452 case JSR: return new JSR(new Label(i1));
453 case RET: return new RET();
454 case RETURN: return new Return();
455 case IRETURN: case LRETURN: case FRETURN: case DRETURN: case ARETURN:
456 return new Return(pop());
458 // Array manipulations //////////////////////////////////////////////////////////////////////////////
460 case IALOAD: case LALOAD: case FALOAD: case DALOAD: case AALOAD:
461 case BALOAD: case CALOAD: case SALOAD: push(new ArrayGet(pop(), pop())); return null;
462 case IASTORE: case LASTORE: case FASTORE: case DASTORE: case AASTORE:
463 case BASTORE: case CASTORE: case SASTORE: return new ArrayPut(pop(), pop(), pop());
465 // Invocation //////////////////////////////////////////////////////////////////////////////
467 case INVOKEVIRTUAL: case INVOKESPECIAL: case INVOKESTATIC: case INVOKEINTERFACE: {
468 Type.Class.Method method = (Type.Class.Method)arg;
469 Expr args[] = new Expr[method.getNumArgs()];
470 for(int i=0; i<args.length; i++) args[args.length-i-1] = pop();
472 case INVOKEVIRTUAL: return push(new InvokeVirtual(method, args, pop()));
473 case INVOKEINTERFACE: return push(new InvokeInterface(method, args, pop()));
474 case INVOKESPECIAL: return push(new InvokeSpecial(method, args, pop()));
475 case INVOKESTATIC: return push(new InvokeStatic(method, args));
479 // Field Access //////////////////////////////////////////////////////////////////////////////
481 case GETSTATIC: push(new Get((Type.Class.Field)arg, null)); return null;
482 case PUTSTATIC: return new Put((Type.Class.Field)arg, pop(), null);
483 case GETFIELD: push(new Get((Type.Class.Field)arg, pop())); return null;
484 case PUTFIELD: return new Put((Type.Class.Field)arg, pop(), pop());
486 // Allocation //////////////////////////////////////////////////////////////////////////////
488 case NEW: push(new Allocate((Type)arg)); return null;
489 case NEWARRAY: push(new Allocate((Type.Array)arg, pop())); return null;
490 case ANEWARRAY: push(new Allocate(Type.OBJECT.makeArray(), pop())); return null;
491 case MULTIANEWARRAY: push(new Allocate(Type.OBJECT.makeArray(i2), null /* FIXME */)); return null;
492 case ARRAYLENGTH: push(new ArrayLength(pop())); return null;
494 // Runtime Type information //////////////////////////////////////////////////////////////////////////////
496 case CHECKCAST: push(new Cast(pop(), (Type)arg)); return null;
497 case INSTANCEOF: push(new InstanceOf(pop(), (Type)arg)); return null;
499 case LDC: case LDC_W: case LDC2_W: push(new Constant(arg)); return null;
501 case BIPUSH: push(new Constant(i1)); // FIXME return null;
502 case SIPUSH: push(new Constant(i1)); // FIXME return null;
504 case TABLESWITCH: new Branch((MethodGen.Switch)arg);
505 case LOOKUPSWITCH: new Branch((MethodGen.Switch)arg);
508 case MONITORENTER: Op.monitorEnter(pop());
509 case MONITOREXIT: Op.monitorExit(pop());
512 case DUP_X1: throw new Error("unimplemented");
513 case DUP_X2: throw new Error("unimplemented");
514 case DUP2_X1: throw new Error("unimplemented");
515 case DUP2_X2: throw new Error("unimplemented");
516 case LCMP: throw new Error("unimplemented");
517 case FCMPL: throw new Error("unimplemented");
518 case FCMPG: throw new Error("unimplemented");
519 case DCMPL: throw new Error("unimplemented");
520 case DCMPG: throw new Error("unimplemented");
521 case GOTO_W: throw new Error("unimplemented");
522 case JSR_W: throw new Error("unimplemented");
523 default: throw new Error("unhandled");
527 public static void main(String[] args) throws Exception {
528 InputStream is = Class.forName(args[0]).getClassLoader().getResourceAsStream(args[0].replace('.', '/')+".class");
529 System.out.println(new ClassFile(new DataInputStream(is), true).debugToString());