gcc/java/typeck.c

   1 /* Handle types for the GNU compiler for the Java(TM) language.
   2    Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2007, 2008
   3    Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.
  20
  21 Java and all Java-based marks are trademarks or registered trademarks
  22 of Sun Microsystems, Inc. in the United States and other countries.
  23 The Free Software Foundation is independent of Sun Microsystems, Inc.  */
  24
  25 /* Written by Per Bothner <bothner@cygnus.com> */
  26
  27 #include "config.h"
  28 #include "system.h"
  29 #include "coretypes.h"
  30 #include "tm.h"
  31 #include "tree.h"
  32 #include "real.h"
  33 #include "obstack.h"
  34 #include "flags.h"
  35 #include "java-tree.h"
  36 #include "jcf.h"
  37 #include "convert.h"
  38 #include "toplev.h"
  39 #include "ggc.h"
  40
  41 static tree convert_ieee_real_to_integer (tree, tree);
  42 static tree parse_signature_type (const unsigned char **,
  43                                   const unsigned char *);
  44 static tree lookup_do (tree, int, tree, tree, tree (*)(tree));
  45 static tree build_null_signature (tree);
  46
  47 tree * type_map;
  48
  49 /* Set the type of the local variable with index SLOT to TYPE. */
  50
  51 void
  52 set_local_type (int slot, tree type)
  53 {
  54   int max_locals = DECL_MAX_LOCALS(current_function_decl);
  55   int nslots = TYPE_IS_WIDE (type) ? 2 : 1;
  56
  57   gcc_assert (slot >= 0 && (slot + nslots - 1 < max_locals));
  58
  59   type_map[slot] = type;
  60   while (--nslots > 0)
  61     type_map[++slot] = void_type_node;
  62 }
  63
  64 /* Convert an IEEE real to an integer type.  The result of such a
  65    conversion when the source operand is a NaN isn't defined by
  66    IEEE754, but by the Java language standard: it must be zero.  Also,
  67    overflows must be clipped to within range.  This conversion
  68    produces something like:
  69
  70       ((expr >= (float)MAX_INT)
  71        ? MAX_INT
  72        : ((expr <= (float)MIN_INT)
  73           ? MIN_INT
  74           : ((expr != expr)
  75              ? 0
  76              : (int)expr))) */
  77
  78 static tree
  79 convert_ieee_real_to_integer (tree type, tree expr)
  80 {
  81   tree result;
  82   expr = save_expr (expr);
  83
  84   result = fold_build3 (COND_EXPR, type,
  85                         fold_build2 (NE_EXPR, boolean_type_node, expr, expr),
  86                          convert (type, integer_zero_node),
  87                          convert_to_integer (type, expr));
  88
  89   result = fold_build3 (COND_EXPR, type,
  90                         fold_build2 (LE_EXPR, boolean_type_node, expr,
  91                                      convert (TREE_TYPE (expr),
  92                                               TYPE_MIN_VALUE (type))),
  93                         TYPE_MIN_VALUE (type),
  94                         result);
  95
  96   result = fold_build3 (COND_EXPR, type,
  97                         fold_build2 (GE_EXPR, boolean_type_node, expr,
  98                                      convert (TREE_TYPE (expr),
  99                                               TYPE_MAX_VALUE (type))),
 100                         TYPE_MAX_VALUE (type),
 101                         result);
 102
 103   return result;
 104 }
 105
 106 /* Create an expression whose value is that of EXPR,
 107    converted to type TYPE.  The TREE_TYPE of the value
 108    is always TYPE.  This function implements all reasonable
 109    conversions; callers should filter out those that are
 110    not permitted by the language being compiled.  */
 111
 112 tree
 113 convert (tree type, tree expr)
 114 {
 115   enum tree_code code = TREE_CODE (type);
 116
 117   if (!expr)
 118    return error_mark_node;
 119
 120   if (type == TREE_TYPE (expr)
 121       || TREE_CODE (expr) == ERROR_MARK)
 122     return expr;
 123   if (TREE_CODE (TREE_TYPE (expr)) == ERROR_MARK)
 124     return error_mark_node;
 125   if (code == VOID_TYPE)
 126     return build1 (CONVERT_EXPR, type, expr);
 127   if (code == BOOLEAN_TYPE)
 128     return fold_convert (type, expr);
 129   if (code == INTEGER_TYPE)
 130     {
 131       if (type == char_type_node || type == promoted_char_type_node)
 132         return fold_convert (type, expr);
 133       if ((really_constant_p (expr) || ! flag_unsafe_math_optimizations)
 134           && TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE)
 135         return convert_ieee_real_to_integer (type, expr);
 136       else
 137         {
 138           /* fold very helpfully sets the overflow status if a type
 139              overflows in a narrowing integer conversion, but Java
 140              doesn't care.  */
 141           tree tmp = fold (convert_to_integer (type, expr));
 142           if (TREE_CODE (tmp) == INTEGER_CST)
 143             TREE_OVERFLOW (tmp) = 0;
 144           return tmp;
 145         }
 146     }
 147   if (code == REAL_TYPE)
 148     return fold (convert_to_real (type, expr));
 149   if (code == POINTER_TYPE)
 150     return fold (convert_to_pointer (type, expr));
 151   error ("conversion to non-scalar type requested");
 152   return error_mark_node;
 153 }
 154
 155
 156 /* Return a data type that has machine mode MODE.
 157    If the mode is an integer,
 158    then UNSIGNEDP selects between signed and unsigned types.  */
 159
 160 tree
 161 java_type_for_mode (enum machine_mode mode, int unsignedp)
 162 {
 163   if (mode == TYPE_MODE (int_type_node))
 164     return unsignedp ? unsigned_int_type_node : int_type_node;
 165   if (mode == TYPE_MODE (long_type_node))
 166     return unsignedp ? unsigned_long_type_node : long_type_node;
 167   if (mode == TYPE_MODE (short_type_node))
 168     return unsignedp ? unsigned_short_type_node : short_type_node;
 169   if (mode == TYPE_MODE (byte_type_node))
 170     return unsignedp ? unsigned_byte_type_node : byte_type_node;
 171   if (mode == TYPE_MODE (float_type_node))
 172     return float_type_node;
 173   if (mode == TYPE_MODE (double_type_node))
 174     return double_type_node;
 175
 176   return 0;
 177 }
 178
 179 /* Return an integer type with BITS bits of precision,
 180    that is unsigned if UNSIGNEDP is nonzero, otherwise signed.  */
 181
 182 tree
 183 java_type_for_size (unsigned bits, int unsignedp)
 184 {
 185   if (bits <= TYPE_PRECISION (byte_type_node))
 186     return unsignedp ? unsigned_byte_type_node : byte_type_node;
 187   if (bits <= TYPE_PRECISION (short_type_node))
 188     return unsignedp ? unsigned_short_type_node : short_type_node;
 189   if (bits <= TYPE_PRECISION (int_type_node))
 190     return unsignedp ? unsigned_int_type_node : int_type_node;
 191   if (bits <= TYPE_PRECISION (long_type_node))
 192     return unsignedp ? unsigned_long_type_node : long_type_node;
 193   return 0;
 194 }
 195
 196 /* Mark EXP saying that we need to be able to take the
 197    address of it; it should not be allocated in a register.
 198    Value is true if successful.  */
 199
 200 bool
 201 java_mark_addressable (tree exp)
 202 {
 203   tree x = exp;
 204   while (1)
 205     switch (TREE_CODE (x))
 206       {
 207       case ADDR_EXPR:
 208       case COMPONENT_REF:
 209       case ARRAY_REF:
 210       case REALPART_EXPR:
 211       case IMAGPART_EXPR:
 212         x = TREE_OPERAND (x, 0);
 213         break;
 214
 215       case TRUTH_ANDIF_EXPR:
 216       case TRUTH_ORIF_EXPR:
 217       case COMPOUND_EXPR:
 218         x = TREE_OPERAND (x, 1);
 219         break;
 220
 221       case COND_EXPR:
 222         return java_mark_addressable (TREE_OPERAND (x, 1))
 223           && java_mark_addressable (TREE_OPERAND (x, 2));
 224
 225       case CONSTRUCTOR:
 226         TREE_ADDRESSABLE (x) = 1;
 227         return true;
 228
 229       case INDIRECT_REF:
 230         /* We sometimes add a cast *(TYPE*)&FOO to handle type and mode
 231            incompatibility problems.  Handle this case by marking FOO.  */
 232         if (TREE_CODE (TREE_OPERAND (x, 0)) == NOP_EXPR
 233             && TREE_CODE (TREE_OPERAND (TREE_OPERAND (x, 0), 0)) == ADDR_EXPR)
 234           {
 235             x = TREE_OPERAND (TREE_OPERAND (x, 0), 0);
 236             break;
 237           }
 238         if (TREE_CODE (TREE_OPERAND (x, 0)) == ADDR_EXPR)
 239           {
 240             x = TREE_OPERAND (x, 0);
 241             break;
 242           }
 243         return true;
 244
 245       case VAR_DECL:
 246       case CONST_DECL:
 247       case PARM_DECL:
 248       case RESULT_DECL:
 249       case FUNCTION_DECL:
 250         TREE_ADDRESSABLE (x) = 1;
 251 #if 0  /* poplevel deals with this now.  */
 252         if (DECL_CONTEXT (x) == 0)
 253           TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
 254 #endif
 255         /* drops through */
 256       default:
 257         return true;
 258     }
 259 }
 260
 261 /* Thorough checking of the arrayness of TYPE.  */
 262
 263 int
 264 is_array_type_p (tree type)
 265 {
 266   return TREE_CODE (type) == POINTER_TYPE
 267     && TREE_CODE (TREE_TYPE (type)) == RECORD_TYPE
 268     && TYPE_ARRAY_P (TREE_TYPE (type));
 269 }
 270
 271 /* Return the length of a Java array type.
 272    Return -1 if the length is unknown or non-constant. */
 273
 274 HOST_WIDE_INT
 275 java_array_type_length (tree array_type)
 276 {
 277   tree arfld;
 278   if (TREE_CODE (array_type) == POINTER_TYPE)
 279     array_type = TREE_TYPE (array_type);
 280   arfld = TREE_CHAIN (TREE_CHAIN (TYPE_FIELDS (array_type)));
 281   if (arfld != NULL_TREE)
 282     {
 283       tree index_type = TYPE_DOMAIN (TREE_TYPE (arfld));
 284       if (index_type != NULL_TREE)
 285         {
 286           tree high = TYPE_MAX_VALUE (index_type);
 287           if (TREE_CODE (high) == INTEGER_CST)
 288             return TREE_INT_CST_LOW (high) + 1;
 289         }
 290     }
 291   return -1;
 292 }
 293
 294 /* An array of unknown length will be ultimately given a length of
 295    -2, so that we can still have `length' producing a negative value
 296    even if found. This was part of an optimization aiming at removing
 297    `length' from static arrays. We could restore it, FIXME.  */
 298
 299 tree
 300 build_prim_array_type (tree element_type, HOST_WIDE_INT length)
 301 {
 302   tree index = NULL;
 303
 304   if (length != -1)
 305     {
 306       tree max_index = build_int_cst (sizetype, length - 1);
 307       index = build_index_type (max_index);
 308     }
 309   return build_array_type (element_type, index);
 310 }
 311
 312 /* Return a Java array type with a given ELEMENT_TYPE and LENGTH.
 313    These are hashed (shared) using IDENTIFIER_SIGNATURE_TYPE.
 314    The LENGTH is -1 if the length is unknown. */
 315
 316 tree
 317 build_java_array_type (tree element_type, HOST_WIDE_INT length)
 318 {
 319   tree sig, t, fld, atype, arfld;
 320   char buf[23];
 321   tree elsig = build_java_signature (element_type);
 322   tree el_name = element_type;
 323   buf[0] = '[';
 324   if (length >= 0)
 325     sprintf (buf+1, HOST_WIDE_INT_PRINT_DEC, length);
 326   else
 327     buf[1] = '\0';
 328   sig = ident_subst (IDENTIFIER_POINTER (elsig), IDENTIFIER_LENGTH (elsig),
 329                      buf, 0, 0, "");
 330   t = IDENTIFIER_SIGNATURE_TYPE (sig);
 331   if (t != NULL_TREE)
 332     return TREE_TYPE (t);
 333   t = make_class ();
 334   IDENTIFIER_SIGNATURE_TYPE (sig) = build_pointer_type (t);
 335   TYPE_ARRAY_P (t) = 1;
 336
 337   if (TREE_CODE (el_name) == POINTER_TYPE)
 338     el_name = TREE_TYPE (el_name);
 339   el_name = TYPE_NAME (el_name);
 340   if (TREE_CODE (el_name) == TYPE_DECL)
 341     el_name = DECL_NAME (el_name);
 342   {
 343     char suffix[23];
 344     if (length >= 0)
 345       sprintf (suffix, "[%d]", (int)length);
 346     else
 347       strcpy (suffix, "[]");
 348     TYPE_NAME (t)
 349       = TYPE_STUB_DECL (t)
 350       = build_decl (TYPE_DECL,
 351                     identifier_subst (el_name, "", '.', '.', suffix),
 352                              t);
 353     TYPE_DECL_SUPPRESS_DEBUG (TYPE_STUB_DECL (t)) = true;
 354   }
 355
 356   set_java_signature (t, sig);
 357   set_super_info (0, t, object_type_node, 0);
 358   if (TREE_CODE (element_type) == RECORD_TYPE)
 359     element_type = promote_type (element_type);
 360   TYPE_ARRAY_ELEMENT (t) = element_type;
 361
 362   /* Add length pseudo-field. */
 363   fld = build_decl (FIELD_DECL, get_identifier ("length"), int_type_node);
 364   TYPE_FIELDS (t) = fld;
 365   DECL_CONTEXT (fld) = t;
 366   FIELD_PUBLIC (fld) = 1;
 367   FIELD_FINAL (fld) = 1;
 368   TREE_READONLY (fld) = 1;
 369
 370   atype = build_prim_array_type (element_type, length);
 371   arfld = build_decl (FIELD_DECL, get_identifier ("data"), atype);
 372   DECL_CONTEXT (arfld) = t;
 373   TREE_CHAIN (fld) = arfld;
 374   DECL_ALIGN (arfld) = TYPE_ALIGN (element_type);
 375
 376   /* We could layout_class, but that loads java.lang.Object prematurely.
 377    * This is called by the parser, and it is a bad idea to do load_class
 378    * in the middle of parsing, because of possible circularity problems. */
 379   push_super_field (t, object_type_node);
 380   layout_type (t);
 381
 382   return t;
 383 }
 384
 385 /* Promote TYPE to the type actually used for fields and parameters. */
 386
 387 tree
 388 promote_type (tree type)
 389 {
 390   switch (TREE_CODE (type))
 391     {
 392     case RECORD_TYPE:
 393       return build_pointer_type (type);
 394     case BOOLEAN_TYPE:
 395       if (type == boolean_type_node)
 396         return promoted_boolean_type_node;
 397       goto handle_int;
 398     case INTEGER_TYPE:
 399       if (type == char_type_node)
 400         return promoted_char_type_node;
 401     handle_int:
 402       if (TYPE_PRECISION (type) < TYPE_PRECISION (int_type_node))
 403         {
 404           if (type == short_type_node)
 405             return promoted_short_type_node;
 406           if (type == byte_type_node)
 407             return promoted_byte_type_node;
 408           return int_type_node;
 409         }
 410       /* ... else fall through ... */
 411     default:
 412       return type;
 413     }
 414 }
 415
 416 /* Parse a signature string, starting at *PTR and ending at LIMIT.
 417    Return the seen TREE_TYPE, updating *PTR. */
 418
 419 static tree
 420 parse_signature_type (const unsigned char **ptr, const unsigned char *limit)
 421 {
 422   tree type;
 423   gcc_assert (*ptr < limit);
 424
 425   switch (**ptr)
 426     {
 427     case 'B':  (*ptr)++;  return byte_type_node;
 428     case 'C':  (*ptr)++;  return char_type_node;
 429     case 'D':  (*ptr)++;  return double_type_node;
 430     case 'F':  (*ptr)++;  return float_type_node;
 431     case 'S':  (*ptr)++;  return short_type_node;
 432     case 'I':  (*ptr)++;  return int_type_node;
 433     case 'J':  (*ptr)++;  return long_type_node;
 434     case 'Z':  (*ptr)++;  return boolean_type_node;
 435     case 'V':  (*ptr)++;  return void_type_node;
 436     case '[':
 437       for ((*ptr)++; (*ptr) < limit && ISDIGIT (**ptr); ) (*ptr)++;
 438       type = parse_signature_type (ptr, limit);
 439       type = build_java_array_type (type, -1);
 440       break;
 441     case 'L':
 442       {
 443         const unsigned char *start = ++(*ptr);
 444         const unsigned char *str = start;
 445         for ( ; ; str++)
 446           {
 447             gcc_assert (str < limit);
 448             if (*str == ';')
 449               break;
 450           }
 451         *ptr = str+1;
 452         type = lookup_class (unmangle_classname ((const char *) start, str - start));
 453         break;
 454       }
 455     default:
 456       gcc_unreachable ();
 457     }
 458   return promote_type (type);
 459 }
 460
 461 /* Parse a Java "mangled" signature string, starting at SIG_STRING,
 462    and SIG_LENGTH bytes long.
 463    Return a gcc type node. */
 464
 465 tree
 466 parse_signature_string (const unsigned char *sig_string, int sig_length)
 467 {
 468   tree result_type;
 469   const unsigned char *str = sig_string;
 470   const unsigned char *limit = str + sig_length;
 471
 472   if (str < limit && str[0] == '(')
 473     {
 474       tree argtype_list = NULL_TREE;
 475       str++;
 476       while (str < limit && str[0] != ')')
 477         {
 478           tree argtype = parse_signature_type (&str, limit);
 479           argtype_list = tree_cons (NULL_TREE, argtype, argtype_list);
 480         }
 481       if (str++, str >= limit)
 482         abort ();
 483       result_type = parse_signature_type (&str, limit);
 484       argtype_list = chainon (nreverse (argtype_list), end_params_node);
 485       result_type = build_function_type (result_type, argtype_list);
 486     }
 487   else
 488     result_type = parse_signature_type (&str, limit);
 489   if (str != limit)
 490     error ("junk at end of signature string");
 491   return result_type;
 492 }
 493
 494 /* Convert a signature to its type.
 495  * Uses IDENTIFIER_SIGNATURE_TYPE as a cache (except for primitive types).
 496  */
 497
 498 tree
 499 get_type_from_signature (tree signature)
 500 {
 501   const unsigned char *sig = (const unsigned char *) IDENTIFIER_POINTER (signature);
 502   int len = IDENTIFIER_LENGTH (signature);
 503   tree type;
 504   /* Primitive types aren't cached. */
 505   if (len <= 1)
 506     return parse_signature_string (sig, len);
 507   type = IDENTIFIER_SIGNATURE_TYPE (signature);
 508   if (type == NULL_TREE)
 509     {
 510       type = parse_signature_string (sig, len);
 511       IDENTIFIER_SIGNATURE_TYPE (signature) = type;
 512     }
 513   return type;
 514 }
 515
 516 /* Ignore signature and always return null.  Used by has_method. */
 517
 518 static tree
 519 build_null_signature (tree type ATTRIBUTE_UNUSED)
 520 {
 521   return NULL_TREE;
 522 }
 523
 524 /* Return the signature string for the arguments of method type TYPE. */
 525
 526 tree
 527 build_java_argument_signature (tree type)
 528 {
 529   extern struct obstack temporary_obstack;
 530   tree sig = TYPE_ARGUMENT_SIGNATURE (type);
 531   if (sig == NULL_TREE)
 532     {
 533       tree args = TYPE_ARG_TYPES (type);
 534       if (TREE_CODE (type) == METHOD_TYPE)
 535         args = TREE_CHAIN (args);  /* Skip "this" argument. */
 536       for (; args != end_params_node; args = TREE_CHAIN (args))
 537         {
 538           tree t = build_java_signature (TREE_VALUE (args));
 539           obstack_grow (&temporary_obstack,
 540                         IDENTIFIER_POINTER (t), IDENTIFIER_LENGTH (t));
 541         }
 542       obstack_1grow (&temporary_obstack, '\0');
 543
 544       sig = get_identifier (obstack_base (&temporary_obstack));
 545       TYPE_ARGUMENT_SIGNATURE (type) = sig;
 546       obstack_free (&temporary_obstack, obstack_base (&temporary_obstack));
 547     }
 548   return sig;
 549 }
 550
 551 /* Return the signature of the given TYPE. */
 552
 553 tree
 554 build_java_signature (tree type)
 555 {
 556   tree sig, t;
 557   while (TREE_CODE (type) == POINTER_TYPE)
 558     type = TREE_TYPE (type);
 559   MAYBE_CREATE_TYPE_TYPE_LANG_SPECIFIC (type);
 560   sig = TYPE_SIGNATURE (type);
 561   if (sig == NULL_TREE)
 562     {
 563       char sg[2];
 564       switch (TREE_CODE (type))
 565         {
 566         case BOOLEAN_TYPE: sg[0] = 'Z';  goto native;
 567         case VOID_TYPE:    sg[0] = 'V';  goto native;
 568         case INTEGER_TYPE:
 569           if (type == char_type_node || type == promoted_char_type_node)
 570             {
 571               sg[0] = 'C';
 572               goto native;
 573             }
 574           switch (TYPE_PRECISION (type))
 575             {
 576             case  8:       sg[0] = 'B';  goto native;
 577             case 16:       sg[0] = 'S';  goto native;
 578             case 32:       sg[0] = 'I';  goto native;
 579             case 64:       sg[0] = 'J';  goto native;
 580             default:  goto bad_type;
 581             }
 582         case REAL_TYPE:
 583           switch (TYPE_PRECISION (type))
 584             {
 585             case 32:       sg[0] = 'F';  goto native;
 586             case 64:       sg[0] = 'D';  goto native;
 587             default:  goto bad_type;
 588             }
 589         native:
 590           sg[1] = 0;
 591           sig = get_identifier (sg);
 592           break;
 593         case RECORD_TYPE:
 594           if (TYPE_ARRAY_P (type))
 595             {
 596               t = build_java_signature (TYPE_ARRAY_ELEMENT (type));
 597               sig = ident_subst (IDENTIFIER_POINTER (t), IDENTIFIER_LENGTH (t),
 598                                  "[", 0, 0, "");
 599             }
 600           else
 601             {
 602               t = DECL_NAME (TYPE_NAME (type));
 603               sig = ident_subst (IDENTIFIER_POINTER (t), IDENTIFIER_LENGTH (t),
 604                                  "L", '.', '/', ";");
 605             }
 606           break;
 607         case METHOD_TYPE:
 608         case FUNCTION_TYPE:
 609           {
 610             extern struct obstack temporary_obstack;
 611             sig = build_java_argument_signature (type);
 612             obstack_1grow (&temporary_obstack, '(');
 613             obstack_grow (&temporary_obstack,
 614                           IDENTIFIER_POINTER (sig), IDENTIFIER_LENGTH (sig));
 615             obstack_1grow (&temporary_obstack, ')');
 616
 617             t = build_java_signature (TREE_TYPE (type));
 618             obstack_grow0 (&temporary_obstack,
 619                            IDENTIFIER_POINTER (t), IDENTIFIER_LENGTH (t));
 620
 621             sig = get_identifier (obstack_base (&temporary_obstack));
 622             obstack_free (&temporary_obstack,
 623                           obstack_base (&temporary_obstack));
 624           }
 625           break;
 626         bad_type:
 627         default:
 628           gcc_unreachable ();
 629         }
 630       TYPE_SIGNATURE (type) = sig;
 631     }
 632   return sig;
 633 }
 634
 635 /* Save signature string SIG (an IDENTIFIER_NODE) in TYPE for future use. */
 636
 637 void
 638 set_java_signature (tree type, tree sig)
 639 {
 640   tree old_sig;
 641   while (TREE_CODE (type) == POINTER_TYPE)
 642     type = TREE_TYPE (type);
 643   MAYBE_CREATE_TYPE_TYPE_LANG_SPECIFIC (type);
 644   old_sig = TYPE_SIGNATURE (type);
 645   if (old_sig != NULL_TREE && old_sig != sig)
 646     abort ();
 647   TYPE_SIGNATURE (type) = sig;
 648 #if 0 /* careful about METHOD_TYPE */
 649   if (IDENTIFIER_SIGNATURE_TYPE (sig) == NULL_TREE && TREE_PERMANENT (type))
 650     IDENTIFIER_SIGNATURE_TYPE (sig) = type;
 651 #endif
 652 }
 653
 654 /* Search in SEARCHED_CLASS and its superclasses for a method matching
 655    METHOD_NAME and signature METHOD_SIGNATURE.  This function will
 656    only search for methods declared in the class hierarchy; interfaces
 657    will not be considered.  Returns NULL_TREE if the method is not
 658    found.  */
 659 tree
 660 lookup_argument_method (tree searched_class, tree method_name,
 661                         tree method_signature)
 662 {
 663   return lookup_do (searched_class, 0,
 664                     method_name, method_signature,
 665                     build_java_argument_signature);
 666 }
 667
 668 /* Like lookup_argument_method, but lets the caller set any flags
 669    desired.  */
 670 tree
 671 lookup_argument_method_generic (tree searched_class, tree method_name,
 672                                 tree method_signature, int flags)
 673 {
 674   return lookup_do (searched_class, flags,
 675                     method_name, method_signature,
 676                     build_java_argument_signature);
 677 }
 678
 679
 680 /* Search in class SEARCHED_CLASS (and its superclasses) for a method
 681    matching METHOD_NAME and signature METHOD_SIGNATURE.  Return a
 682    FUNCTION_DECL on success, or NULL_TREE if none found.  (Contrast
 683    lookup_argument_method, which ignores return type.)  If
 684    SEARCHED_CLASS is an interface, search it too. */
 685 tree
 686 lookup_java_method (tree searched_class, tree method_name,
 687                     tree method_signature)
 688 {
 689   return lookup_do (searched_class, SEARCH_INTERFACE, method_name,
 690                     method_signature, build_java_signature);
 691 }
 692
 693 /* Return true iff KLASS (or its ancestors) has a method METHOD_NAME.  */
 694 int
 695 has_method (tree klass, tree method_name)
 696 {
 697   return lookup_do (klass, SEARCH_INTERFACE,
 698                     method_name, NULL_TREE,
 699                     build_null_signature) != NULL_TREE;
 700 }
 701
 702 /* Search in class SEARCHED_CLASS, but not its superclasses, for a
 703    method matching METHOD_NAME and signature SIGNATURE.  A private
 704    helper for lookup_do.  */
 705 static tree
 706 shallow_find_method (tree searched_class, int flags, tree method_name,
 707              tree signature, tree (*signature_builder) (tree))
 708 {
 709   tree method;
 710   for (method = TYPE_METHODS (searched_class);
 711        method != NULL_TREE;  method = TREE_CHAIN (method))
 712     {
 713       tree method_sig = (*signature_builder) (TREE_TYPE (method));
 714       if (DECL_NAME (method) == method_name && method_sig == signature)
 715         {
 716           /* If the caller requires a visible method, then we
 717              skip invisible methods here.  */
 718           if (! (flags & SEARCH_VISIBLE)
 719               || ! METHOD_INVISIBLE (method))
 720             return method;
 721         }
 722     }
 723   return NULL_TREE;
 724 }
 725
 726 /* Search in the superclasses of SEARCHED_CLASS for a method matching
 727    METHOD_NAME and signature SIGNATURE.  A private helper for
 728    lookup_do.  */
 729 static tree
 730 find_method_in_superclasses (tree searched_class, int flags,
 731                              tree method_name, tree signature,
 732                              tree (*signature_builder) (tree))
 733 {
 734   tree klass;
 735   for (klass = CLASSTYPE_SUPER (searched_class); klass != NULL_TREE;
 736        klass = CLASSTYPE_SUPER (klass))
 737     {
 738       tree method;
 739       method = shallow_find_method (klass, flags, method_name,
 740                                     signature, signature_builder);
 741       if (method != NULL_TREE)
 742         return method;
 743     }
 744
 745   return NULL_TREE;
 746 }
 747
 748 /* Search in the interfaces of SEARCHED_CLASS and its superinterfaces
 749    for a method matching METHOD_NAME and signature SIGNATURE.  A
 750    private helper for lookup_do.  */
 751 static tree
 752 find_method_in_interfaces (tree searched_class, int flags, tree method_name,
 753                            tree signature, tree (*signature_builder) (tree))
 754 {
 755   int i;
 756   tree binfo, base_binfo;
 757
 758   for (binfo = TYPE_BINFO (searched_class), i = 1;
 759        BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
 760     {
 761       tree iclass = BINFO_TYPE (base_binfo);
 762       tree method;
 763
 764       /* If the superinterface hasn't been loaded yet, do so now.  */
 765       if (!CLASS_LOADED_P (iclass))
 766         load_class (iclass, 1);
 767
 768       /* First, we look in ICLASS.  If that doesn't work we'll
 769          recursively look through all its superinterfaces.  */
 770       method = shallow_find_method (iclass, flags, method_name,
 771                                     signature, signature_builder);
 772       if (method != NULL_TREE)
 773         return method;
 774
 775       method = find_method_in_interfaces
 776         (iclass, flags, method_name, signature, signature_builder);
 777       if (method != NULL_TREE)
 778         return method;
 779     }
 780
 781   return NULL_TREE;
 782 }
 783
 784
 785 /* Search in class SEARCHED_CLASS (and its superclasses) for a method
 786    matching METHOD_NAME and signature SIGNATURE.  FLAGS control some
 787    parameters of the search.
 788
 789    SEARCH_INTERFACE means also search interfaces and superinterfaces
 790    of SEARCHED_CLASS.
 791
 792    SEARCH_SUPER means skip SEARCHED_CLASS and start with its
 793    superclass.
 794
 795    SEARCH_VISIBLE means skip methods for which METHOD_INVISIBLE is
 796    set.
 797
 798    Return the matched method DECL or NULL_TREE.  SIGNATURE_BUILDER is
 799    used on method candidates to build their (sometimes partial)
 800    signature.  */
 801 static tree
 802 lookup_do (tree searched_class, int flags, tree method_name,
 803            tree signature, tree (*signature_builder) (tree))
 804 {
 805   tree method;
 806   tree orig_class = searched_class;
 807
 808   if (searched_class == NULL_TREE)
 809     return NULL_TREE;
 810
 811   if (flags & SEARCH_SUPER)
 812     {
 813       searched_class = CLASSTYPE_SUPER (searched_class);
 814       if (searched_class == NULL_TREE)
 815         return NULL_TREE;
 816     }
 817
 818   /* First look in our own methods.  */
 819   method = shallow_find_method (searched_class, flags, method_name,
 820                                 signature, signature_builder);
 821   if (method)
 822     return method;
 823
 824   /* Then look in our superclasses.  */
 825   if (! CLASS_INTERFACE (TYPE_NAME (searched_class)))
 826     method = find_method_in_superclasses (searched_class, flags, method_name,
 827                                           signature, signature_builder);
 828   if (method)
 829     return method;
 830
 831   /* If that doesn't work, look in our interfaces.  */
 832   if (flags & SEARCH_INTERFACE)
 833     method = find_method_in_interfaces (orig_class, flags, method_name,
 834                                         signature, signature_builder);
 835
 836   return method;
 837 }
 838
 839 /* Search in class CLAS for a constructor matching METHOD_SIGNATURE.
 840    Return a FUNCTION_DECL on success, or NULL_TREE if none found. */
 841
 842 tree
 843 lookup_java_constructor (tree clas, tree method_signature)
 844 {
 845   tree method = TYPE_METHODS (clas);
 846   for ( ; method != NULL_TREE;  method = TREE_CHAIN (method))
 847     {
 848       tree method_sig = build_java_signature (TREE_TYPE (method));
 849       if (DECL_CONSTRUCTOR_P (method) && method_sig == method_signature)
 850         return method;
 851     }
 852   return NULL_TREE;
 853 }
 854
 855 /* Return a type which is the Binary Numeric Promotion of the pair T1,
 856    T2 and convert EXP1 and/or EXP2. See 5.6.2 Binary Numeric
 857    Promotion. It assumes that both T1 and T2 are eligible to BNP. */
 858
 859 tree
 860 binary_numeric_promotion (tree t1, tree t2, tree *exp1, tree *exp2)
 861 {
 862   if (t1 == double_type_node || t2 == double_type_node)
 863     {
 864       if (t1 != double_type_node)
 865         *exp1 = convert (double_type_node, *exp1);
 866       if (t2 != double_type_node)
 867         *exp2 = convert (double_type_node, *exp2);
 868       return double_type_node;
 869     }
 870   if (t1 == float_type_node || t2 == float_type_node)
 871     {
 872       if (t1 != float_type_node)
 873         *exp1 = convert (float_type_node, *exp1);
 874       if (t2 != float_type_node)
 875         *exp2 = convert (float_type_node, *exp2);
 876       return float_type_node;
 877     }
 878   if (t1 == long_type_node || t2 == long_type_node)
 879     {
 880       if (t1 != long_type_node)
 881         *exp1 = convert (long_type_node, *exp1);
 882       if (t2 != long_type_node)
 883         *exp2 = convert (long_type_node, *exp2);
 884       return long_type_node;
 885     }
 886
 887   if (t1 != int_type_node)
 888     *exp1 = convert (int_type_node, *exp1);
 889   if (t2 != int_type_node)
 890     *exp2 = convert (int_type_node, *exp2);
 891   return int_type_node;
 892 }