gerrit.simantics Code Review - simantics/platform.git/blob

   1 package org.simantics.scl.compiler.internal.codegen.utils;
   2
   3 import org.cojen.classfile.MethodDesc;
   4 import org.cojen.classfile.TypeDesc;
   5 import org.objectweb.asm.Label;
   6 import org.objectweb.asm.MethodVisitor;
   7 import org.objectweb.asm.Opcodes;
   8 import org.objectweb.asm.Type;
   9
  10 public class MethodBuilderBase {
  11     private ClassBuilder classBuilder;
  12     private MethodVisitor methodVisitor;
  13     private LocalVariable[] parameters;
  14     private int localVariableCount = 0;
  15
  16     public MethodBuilderBase(ClassBuilder classBuilder, boolean isStatic, MethodVisitor methodVisitor, TypeDesc[] parameterTypes) {
  17         this.classBuilder = classBuilder;
  18         this.methodVisitor = methodVisitor;
  19         this.parameters = new LocalVariable[parameterTypes.length];
  20         if(!isStatic)
  21             ++localVariableCount;
  22         for(int i=0;i<parameterTypes.length;++i) {
  23             parameters[i] = createLocalVariable("p" + i, parameterTypes[i]);
  24             methodVisitor.visitParameter("p" + i, Opcodes.ACC_PUBLIC);
  25         }
  26         methodVisitor.visitCode();
  27     }
  28
  29     public void loadConstant(boolean value) {
  30         if(value)
  31             methodVisitor.visitInsn(Opcodes.ICONST_1);
  32         else
  33             methodVisitor.visitInsn(Opcodes.ICONST_0);
  34     }
  35
  36     public void loadConstant(int value) {
  37         if (value >= -1 && value <= 5) {
  38             methodVisitor.visitInsn(Opcodes.ICONST_0 + value);
  39         } else if (value >= Byte.MIN_VALUE && value <= Byte.MAX_VALUE) {
  40             methodVisitor.visitIntInsn(Opcodes.BIPUSH, value);
  41         } else if (value >= Short.MIN_VALUE && value <= Short.MAX_VALUE) {
  42             methodVisitor.visitIntInsn(Opcodes.SIPUSH, value);
  43         } else {
  44             methodVisitor.visitLdcInsn(value);
  45         }
  46     }
  47
  48     public void loadConstant(long value) {
  49         if(value == 0L)
  50             methodVisitor.visitInsn(Opcodes.LCONST_0);
  51         else if(value == 1L)
  52             methodVisitor.visitInsn(Opcodes.LCONST_1);
  53         else
  54             methodVisitor.visitLdcInsn(value);
  55     }
  56
  57     public void loadConstant(float value) {
  58         if(value == 0.0f)
  59             methodVisitor.visitInsn(Opcodes.FCONST_0);
  60         else if(value == 1.0f)
  61             methodVisitor.visitInsn(Opcodes.FCONST_1);
  62         else
  63             methodVisitor.visitLdcInsn(value);
  64     }
  65
  66     public void loadConstant(double value) {
  67         if(value == 0.0)
  68             methodVisitor.visitInsn(Opcodes.DCONST_0);
  69         else if(value == 1.0)
  70             methodVisitor.visitInsn(Opcodes.DCONST_1);
  71         else
  72             methodVisitor.visitLdcInsn(value);
  73     }
  74
  75     public void loadConstant(String value) {
  76         methodVisitor.visitLdcInsn(value);
  77     }
  78
  79     public void loadConstant(TypeDesc value) {
  80         if(value.isPrimitive())
  81             loadStaticField(getClassName(value.toObjectType()), "TYPE", Constants.CLASS);
  82         else
  83             methodVisitor.visitLdcInsn(Type.getType(value.getDescriptor()));
  84     }
  85
  86     public void dup() {
  87         methodVisitor.visitInsn(Opcodes.DUP);
  88     }
  89
  90     public void dup2() {
  91         methodVisitor.visitInsn(Opcodes.DUP2);
  92     }
  93
  94     public void dupX1() {
  95         methodVisitor.visitInsn(Opcodes.DUP_X1);
  96     }
  97
  98     public void swap() {
  99         methodVisitor.visitInsn(Opcodes.SWAP);
 100     }
 101
 102     public void pop() {
 103         methodVisitor.visitInsn(Opcodes.POP);
 104     }
 105
 106     public void pop2() {
 107         methodVisitor.visitInsn(Opcodes.POP2);
 108     }
 109
 110     public void convert(TypeDesc fromType, TypeDesc toType) {
 111         switch(fromType.getTypeCode() + 16*toType.getTypeCode()) {
 112         case TypeDesc.OBJECT_CODE + 16*TypeDesc.BOOLEAN_CODE:
 113             methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Boolean", "booleanValue", "()Z", false);
 114             return;
 115         case TypeDesc.OBJECT_CODE + 16*TypeDesc.INT_CODE:
 116             methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Integer", "intValue", "()I", false);
 117             return;
 118         case TypeDesc.OBJECT_CODE + 16*TypeDesc.FLOAT_CODE:
 119             methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Float", "floatValue", "()F", false);
 120             return;
 121         case TypeDesc.OBJECT_CODE + 16*TypeDesc.DOUBLE_CODE:
 122             methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Double", "doubleValue", "()D", false);
 123             return;
 124         case TypeDesc.OBJECT_CODE + 16*TypeDesc.CHAR_CODE:
 125             methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Character", "charValue", "()C", false);
 126             return;
 127         case TypeDesc.OBJECT_CODE + 16*TypeDesc.LONG_CODE:
 128             methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Long", "longValue", "()J", false);
 129             return;
 130         case TypeDesc.OBJECT_CODE + 16*TypeDesc.SHORT_CODE:
 131             methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Short", "shortValue", "()S", false);
 132             return;
 133         case TypeDesc.OBJECT_CODE + 16*TypeDesc.BYTE_CODE:
 134             methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Byte", "byteValue", "()B", false);
 135             return;
 136         case TypeDesc.DOUBLE_CODE + 16*TypeDesc.FLOAT_CODE:
 137             methodVisitor.visitInsn(Opcodes.D2F);
 138             return;
 139         case TypeDesc.FLOAT_CODE + 16*TypeDesc.DOUBLE_CODE:
 140             methodVisitor.visitInsn(Opcodes.F2D);
 141             return;
 142         case TypeDesc.INT_CODE + 16*TypeDesc.DOUBLE_CODE:
 143             methodVisitor.visitInsn(Opcodes.I2D);
 144             return;
 145         case TypeDesc.DOUBLE_CODE + 16*TypeDesc.INT_CODE:
 146             methodVisitor.visitInsn(Opcodes.D2I);
 147             return;
 148         case TypeDesc.INT_CODE + 16*TypeDesc.FLOAT_CODE:
 149             methodVisitor.visitInsn(Opcodes.I2F);
 150             return;
 151         case TypeDesc.FLOAT_CODE + 16*TypeDesc.INT_CODE:
 152             methodVisitor.visitInsn(Opcodes.F2I);
 153             return;
 154         case TypeDesc.LONG_CODE + 16*TypeDesc.FLOAT_CODE:
 155             methodVisitor.visitInsn(Opcodes.L2F);
 156             return;
 157         case TypeDesc.FLOAT_CODE + 16*TypeDesc.LONG_CODE:
 158             methodVisitor.visitInsn(Opcodes.F2L);
 159             return;
 160         case TypeDesc.LONG_CODE + 16*TypeDesc.DOUBLE_CODE:
 161             methodVisitor.visitInsn(Opcodes.L2D);
 162             return;
 163         case TypeDesc.DOUBLE_CODE + 16*TypeDesc.LONG_CODE:
 164             methodVisitor.visitInsn(Opcodes.D2L);
 165             return;
 166         case TypeDesc.INT_CODE + 16*TypeDesc.LONG_CODE:
 167             methodVisitor.visitInsn(Opcodes.I2L);
 168             return;
 169         case TypeDesc.LONG_CODE + 16*TypeDesc.INT_CODE:
 170             methodVisitor.visitInsn(Opcodes.L2I);
 171             return;
 172         case TypeDesc.INT_CODE + 16*TypeDesc.SHORT_CODE:
 173             methodVisitor.visitInsn(Opcodes.I2S);
 174             return;
 175         case TypeDesc.SHORT_CODE + 16*TypeDesc.INT_CODE:
 176         case TypeDesc.BOOLEAN_CODE + 16*TypeDesc.INT_CODE:
 177             // NOP
 178             return;
 179         case TypeDesc.INT_CODE + 16*TypeDesc.BYTE_CODE:
 180             methodVisitor.visitInsn(Opcodes.I2B);
 181             return;
 182         case TypeDesc.BYTE_CODE + 16*TypeDesc.INT_CODE:
 183             // NOP
 184             return;
 185         case TypeDesc.INT_CODE + 16*TypeDesc.CHAR_CODE:
 186             methodVisitor.visitInsn(Opcodes.I2C);
 187             return;
 188         case TypeDesc.CHAR_CODE + 16*TypeDesc.INT_CODE:
 189             // NOP
 190             return;
 191         default:
 192             System.out.println("convert: " + fromType + " -> " + toType);
 193         }
 194     }
 195
 196     public void convert(TypeDesc fromType, TypeDesc toType,
 197             int convertFpNormal) {
 198         convert(fromType, toType);
 199     }
 200
 201     public LocalVariable createLocalVariable(String name, TypeDesc type) {
 202         int index = localVariableCount;
 203         localVariableCount += type == TypeDesc.DOUBLE || type == TypeDesc.LONG ? 2 : 1;
 204         return new LocalVariable(index, type);
 205     }
 206
 207     public void storeLocal(LocalVariable local) {
 208         switch(local.type.getTypeCode()) {
 209         case TypeDesc.BOOLEAN_CODE:
 210         case TypeDesc.BYTE_CODE:
 211         case TypeDesc.CHAR_CODE:
 212         case TypeDesc.SHORT_CODE:
 213         case TypeDesc.INT_CODE:
 214             methodVisitor.visitVarInsn(Opcodes.ISTORE, local.index);
 215             break;
 216         case TypeDesc.FLOAT_CODE:
 217             methodVisitor.visitVarInsn(Opcodes.FSTORE, local.index);
 218             break;
 219         case TypeDesc.DOUBLE_CODE:
 220             methodVisitor.visitVarInsn(Opcodes.DSTORE, local.index);
 221             break;
 222         case TypeDesc.LONG_CODE:
 223             methodVisitor.visitVarInsn(Opcodes.LSTORE, local.index);
 224             break;
 225         case TypeDesc.OBJECT_CODE:
 226             methodVisitor.visitVarInsn(Opcodes.ASTORE, local.index);
 227             break;
 228         default: throw new IllegalArgumentException();
 229         }
 230     }
 231
 232     public void ifZeroComparisonBranch(Label location, String choice) {
 233         int opcode;
 234         if(choice.equals("!="))
 235             opcode = Opcodes.IFNE;
 236         else if(choice.equals("=="))
 237             opcode = Opcodes.IFEQ;
 238         else if(choice.equals("<"))
 239             opcode = Opcodes.IFLT;
 240         else if(choice.equals(">"))
 241             opcode = Opcodes.IFGT;
 242         else if(choice.equals("<="))
 243             opcode = Opcodes.IFLE;
 244         else if(choice.equals(">="))
 245             opcode = Opcodes.IFGE;
 246         else
 247             throw new IllegalArgumentException("Invalid choice \"" + choice + "\".");
 248         methodVisitor.visitJumpInsn(opcode, location);
 249     }
 250
 251     public void ifComparisonBranch(Label location, String choice, TypeDesc type) {
 252         switch(type.getTypeCode()) {
 253         case TypeDesc.BOOLEAN_CODE:
 254         case TypeDesc.BYTE_CODE:
 255         case TypeDesc.CHAR_CODE:
 256         case TypeDesc.SHORT_CODE:
 257         case TypeDesc.INT_CODE: {
 258             int opcode;
 259             if(choice.equals("!="))
 260                 opcode = Opcodes.IF_ICMPNE;
 261             else if(choice.equals("=="))
 262                 opcode = Opcodes.IF_ICMPEQ;
 263             else if(choice.equals("<"))
 264                 opcode = Opcodes.IF_ICMPLT;
 265             else if(choice.equals(">"))
 266                 opcode = Opcodes.IF_ICMPGT;
 267             else if(choice.equals("<="))
 268                 opcode = Opcodes.IF_ICMPLE;
 269             else if(choice.equals(">="))
 270                 opcode = Opcodes.IF_ICMPGE;
 271             else
 272                 throw new IllegalArgumentException("Invalid choice \"" + choice + "\".");
 273             methodVisitor.visitJumpInsn(opcode, location);
 274         } break;
 275         case TypeDesc.FLOAT_CODE:
 276             methodVisitor.visitInsn(Opcodes.FCMPL);
 277             ifZeroComparisonBranch(location, choice);
 278             break;
 279         case TypeDesc.DOUBLE_CODE:
 280             methodVisitor.visitInsn(Opcodes.DCMPL);
 281             ifZeroComparisonBranch(location, choice);
 282             break;
 283         case TypeDesc.LONG_CODE:
 284             methodVisitor.visitInsn(Opcodes.LCMP);
 285             ifZeroComparisonBranch(location, choice);
 286             break;
 287         case TypeDesc.OBJECT_CODE: {
 288             int opcode;
 289             if(choice.equals("!="))
 290                 opcode = Opcodes.IF_ACMPNE;
 291             else if(choice.equals("=="))
 292                 opcode = Opcodes.IF_ACMPEQ;
 293             else
 294                 throw new IllegalArgumentException("Invalid choice \"" + choice + "\".");
 295             methodVisitor.visitJumpInsn(opcode, location);
 296         } break;
 297         default: throw new IllegalArgumentException();
 298         }
 299     }
 300
 301     public void ifNullBranch(Label location, boolean choice) {
 302         methodVisitor.visitJumpInsn(choice ? Opcodes.IFNULL : Opcodes.IFNONNULL, location);
 303     }
 304
 305     public void branch(Label location) {
 306         methodVisitor.visitJumpInsn(Opcodes.GOTO, location);
 307     }
 308
 309     public Label createLabel() {
 310         return new Label();
 311     }
 312
 313     public void setLocation(Label label) {
 314         methodVisitor.visitLabel(label);
 315     }
 316
 317     public void loadLocal(LocalVariable local) {
 318         switch(local.type.getTypeCode()) {
 319         case TypeDesc.BOOLEAN_CODE:
 320         case TypeDesc.BYTE_CODE:
 321         case TypeDesc.CHAR_CODE:
 322         case TypeDesc.SHORT_CODE:
 323         case TypeDesc.INT_CODE:
 324             methodVisitor.visitVarInsn(Opcodes.ILOAD, local.index);
 325             break;
 326         case TypeDesc.FLOAT_CODE:
 327             methodVisitor.visitVarInsn(Opcodes.FLOAD, local.index);
 328             break;
 329         case TypeDesc.DOUBLE_CODE:
 330             methodVisitor.visitVarInsn(Opcodes.DLOAD, local.index);
 331             break;
 332         case TypeDesc.LONG_CODE:
 333             methodVisitor.visitVarInsn(Opcodes.LLOAD, local.index);
 334             break;
 335         case TypeDesc.OBJECT_CODE:
 336             methodVisitor.visitVarInsn(Opcodes.ALOAD, local.index);
 337             break;
 338         default: throw new IllegalArgumentException();
 339         }
 340     }
 341
 342     public void loadNull() {
 343         methodVisitor.visitInsn(Opcodes.ACONST_NULL);
 344     }
 345
 346     public void loadFromArray(TypeDesc type) {
 347         switch(type.getTypeCode()) {
 348         case TypeDesc.BOOLEAN_CODE:
 349             methodVisitor.visitInsn(Opcodes.BALOAD);
 350             break;
 351         case TypeDesc.BYTE_CODE:
 352             methodVisitor.visitInsn(Opcodes.BALOAD);
 353             break;
 354         case TypeDesc.CHAR_CODE:
 355             methodVisitor.visitInsn(Opcodes.CALOAD);
 356             break;
 357         case TypeDesc.SHORT_CODE:
 358             methodVisitor.visitInsn(Opcodes.SALOAD);
 359             break;
 360         case TypeDesc.INT_CODE:
 361             methodVisitor.visitInsn(Opcodes.IALOAD);
 362             break;
 363         case TypeDesc.FLOAT_CODE:
 364             methodVisitor.visitInsn(Opcodes.FALOAD);
 365             break;
 366         case TypeDesc.DOUBLE_CODE:
 367             methodVisitor.visitInsn(Opcodes.DALOAD);
 368             break;
 369         case TypeDesc.LONG_CODE:
 370             methodVisitor.visitInsn(Opcodes.LALOAD);
 371             break;
 372         case TypeDesc.OBJECT_CODE:
 373             methodVisitor.visitInsn(Opcodes.AALOAD);
 374             break;
 375         default: throw new IllegalArgumentException();
 376         }
 377     }
 378
 379     public void invokeInterface(String className, String methodName,
 380             TypeDesc ret, TypeDesc[] params) {
 381         checkClassName(className);
 382         checkParameters(params);
 383         methodVisitor.visitMethodInsn(Opcodes.INVOKEINTERFACE, className, methodName,
 384                 MethodDesc.forArguments(ret, params).getDescriptor(), true);
 385     }
 386
 387     public void invokeInterface(TypeDesc className, String methodName,
 388             TypeDesc ret, TypeDesc[] params) {
 389         invokeInterface(getClassName(className), methodName, ret, params);
 390     }
 391
 392     public void invokeVirtual(String className, String methodName,
 393             TypeDesc ret, TypeDesc[] params) {
 394         checkClassName(className);
 395         checkParameters(params);
 396         methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, className, methodName,
 397                 MethodDesc.forArguments(ret, params).getDescriptor(), false);
 398     }
 399
 400     public void invokeVirtual(TypeDesc className, String methodName, TypeDesc ret,
 401             TypeDesc[] params) {
 402         invokeVirtual(getClassName(className), methodName, ret, params);
 403     }
 404
 405     public void invokeConstructor(String className, TypeDesc[] params) {
 406         checkClassName(className);
 407         checkParameters(params);
 408         methodVisitor.visitMethodInsn(Opcodes.INVOKESPECIAL, className, "<init>",
 409                 MethodDesc.forArguments(TypeDesc.VOID, params).getDescriptor(), false);
 410     }
 411
 412     public void invokeConstructor(TypeDesc className, TypeDesc[] params) {
 413         invokeConstructor(getClassName(className), params);
 414     }
 415
 416     public void invokeSuperConstructor(TypeDesc[] params) {
 417         invokeConstructor(classBuilder.getSuperClassName(), params);
 418     }
 419
 420     public void invokeStatic(String className, String methodName, TypeDesc ret,
 421             TypeDesc[] params) {
 422         checkClassName(className);
 423         checkParameters(params);
 424         methodVisitor.visitMethodInsn(Opcodes.INVOKESTATIC, className, methodName,
 425                 MethodDesc.forArguments(ret, params).getDescriptor(), false);
 426     }
 427
 428     public void invokeStatic(TypeDesc className, String methodName, TypeDesc ret,
 429             TypeDesc[] params) {
 430         invokeStatic(getClassName(className), methodName, ret, params);
 431     }
 432
 433     public void newObject(TypeDesc type) {
 434         methodVisitor.visitTypeInsn(Opcodes.NEW, getClassName(type));
 435     }
 436
 437     public void newObject(String type) {
 438         methodVisitor.visitTypeInsn(Opcodes.NEW, type);
 439     }
 440
 441     public void newObject(TypeDesc type, int dimensions) {
 442         methodVisitor.visitMultiANewArrayInsn(type.getDescriptor(), dimensions);
 443     }
 444
 445     public void loadStaticField(String className, String fieldName, TypeDesc type) {
 446         checkClassName(className);
 447         methodVisitor.visitFieldInsn(Opcodes.GETSTATIC, className, fieldName, type.getDescriptor());
 448     }
 449
 450     public void loadStaticField(TypeDesc className, String fieldName,
 451             TypeDesc type) {
 452         loadStaticField(getClassName(className), fieldName, type);
 453     }
 454
 455     public void loadField(String className, String fieldName, TypeDesc type) {
 456         checkClassName(className);
 457         methodVisitor.visitFieldInsn(Opcodes.GETFIELD, className, fieldName, type.getDescriptor());
 458     }
 459
 460     public void storeStaticField(String className, String fieldName,
 461             TypeDesc type) {
 462         checkClassName(className);
 463         methodVisitor.visitFieldInsn(Opcodes.PUTSTATIC, className, fieldName, type.getDescriptor());
 464     }
 465
 466     public void storeField(String className, String fieldName, TypeDesc type) {
 467         checkClassName(className);
 468         methodVisitor.visitFieldInsn(Opcodes.PUTFIELD, className, fieldName, type.getDescriptor());
 469     }
 470
 471     public void storeToArray(TypeDesc type) {
 472         switch(type.getTypeCode()) {
 473         case TypeDesc.BOOLEAN_CODE:
 474             methodVisitor.visitInsn(Opcodes.BASTORE);
 475             break;
 476         case TypeDesc.BYTE_CODE:
 477             methodVisitor.visitInsn(Opcodes.BASTORE);
 478             break;
 479         case TypeDesc.CHAR_CODE:
 480             methodVisitor.visitInsn(Opcodes.CASTORE);
 481             break;
 482         case TypeDesc.SHORT_CODE:
 483             methodVisitor.visitInsn(Opcodes.SASTORE);
 484             break;
 485         case TypeDesc.INT_CODE:
 486             methodVisitor.visitInsn(Opcodes.IASTORE);
 487             break;
 488         case TypeDesc.FLOAT_CODE:
 489             methodVisitor.visitInsn(Opcodes.FASTORE);
 490             break;
 491         case TypeDesc.DOUBLE_CODE:
 492             methodVisitor.visitInsn(Opcodes.DASTORE);
 493             break;
 494         case TypeDesc.LONG_CODE:
 495             methodVisitor.visitInsn(Opcodes.LASTORE);
 496             break;
 497         case TypeDesc.OBJECT_CODE:
 498             methodVisitor.visitInsn(Opcodes.AASTORE);
 499             break;
 500         default: throw new IllegalArgumentException();
 501         }
 502     }
 503
 504     public void math(int opcode) {
 505         methodVisitor.visitInsn(opcode);
 506     }
 507
 508     public void throwObject() {
 509         methodVisitor.visitInsn(Opcodes.ATHROW);
 510     }
 511
 512     public void checkCast(TypeDesc type) {
 513         methodVisitor.visitTypeInsn(Opcodes.CHECKCAST, getClassName(type));
 514     }
 515
 516     public void instanceOf(TypeDesc type) {
 517         methodVisitor.visitTypeInsn(Opcodes.INSTANCEOF, getClassName(type));
 518     }
 519
 520     public void arrayLength() {
 521         methodVisitor.visitInsn(Opcodes.ARRAYLENGTH);
 522     }
 523
 524     public void loadThis() {
 525         methodVisitor.visitVarInsn(Opcodes.ALOAD, 0);
 526     }
 527
 528     public LocalVariable getParameter(int index) {
 529         return parameters[index];
 530     }
 531
 532     public void returnVoid() {
 533         methodVisitor.visitInsn(Opcodes.RETURN);
 534     }
 535
 536     public void returnValue(TypeDesc type) {
 537         switch(type.getTypeCode()) {
 538         case TypeDesc.VOID_CODE:
 539             methodVisitor.visitInsn(Opcodes.RETURN);
 540             break;
 541         case TypeDesc.BOOLEAN_CODE:
 542         case TypeDesc.BYTE_CODE:
 543         case TypeDesc.CHAR_CODE:
 544         case TypeDesc.SHORT_CODE:
 545         case TypeDesc.INT_CODE:
 546             methodVisitor.visitInsn(Opcodes.IRETURN);
 547             break;
 548         case TypeDesc.FLOAT_CODE:
 549             methodVisitor.visitInsn(Opcodes.FRETURN);
 550             break;
 551         case TypeDesc.DOUBLE_CODE:
 552             methodVisitor.visitInsn(Opcodes.DRETURN);
 553             break;
 554         case TypeDesc.LONG_CODE:
 555             methodVisitor.visitInsn(Opcodes.LRETURN);
 556             break;
 557         case TypeDesc.OBJECT_CODE:
 558             methodVisitor.visitInsn(Opcodes.ARETURN);
 559             break;
 560         default: throw new IllegalArgumentException();
 561         }
 562     }
 563
 564     public void finish() {
 565         methodVisitor.visitMaxs(0, 0);
 566         methodVisitor.visitEnd();
 567     }
 568
 569     public String getClassName() {
 570         return classBuilder.className;
 571     }
 572
 573     public static String getClassName(TypeDesc typeDesc) {
 574         if(typeDesc.isArray())
 575             return typeDesc.getDescriptor();
 576         else
 577             return typeDesc.getFullName().replace('.', '/');
 578     }
 579
 580     private static void checkClassName(String className) {
 581         ClassBuilder.checkClassName(className);
 582     }
 583
 584     public static String getClassName(Class<?> clazz) {
 585         return clazz.getName().replace('.', '/');
 586     }
 587
 588     public void switch_(int[] values, Label[] labels, Label defaultLabel) {
 589         int lo = values[0];
 590         int hi = values[values.length-1];
 591         long table_space_cost = 4 + ((long) hi - lo + 1); // words
 592         long table_time_cost = 3; // comparisons
 593         long lookup_space_cost = 3 + 2 * (long) values.length;
 594         long lookup_time_cost = values.length;
 595         if(values.length > 0 &&
 596             table_space_cost + 3 * table_time_cost <=
 597             lookup_space_cost + 3 * lookup_time_cost) {
 598             Label[] table = new Label[hi - lo + 1];
 599             for(int i=0,j=0;i<table.length;++i) {
 600                 int id = lo+i;
 601                 if(values[j] == id) {
 602                     table[i] = labels[j];
 603                     ++j;
 604                 }
 605                 else
 606                     table[i] = defaultLabel;
 607             }
 608             methodVisitor.visitTableSwitchInsn(lo, hi, defaultLabel, table);
 609         }
 610         else
 611             methodVisitor.visitLookupSwitchInsn(defaultLabel, values, labels);
 612     }
 613
 614     private static void checkParameters(TypeDesc[] params) {
 615         for(TypeDesc param : params)
 616             if(param.equals(TypeDesc.VOID))
 617                 throw new IllegalArgumentException();
 618     }
 619 }