gcc/convert.c

   1 /* Utility routines for data type conversion for GCC.
   2    Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1997, 1998,
   3    2000, 2001, 2002, 2003 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 it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.  */
  21
  22
  23 /* These routines are somewhat language-independent utility function
  24    intended to be called by the language-specific convert () functions.  */
  25
  26 #include "config.h"
  27 #include "system.h"
  28 #include "coretypes.h"
  29 #include "tm.h"
  30 #include "tree.h"
  31 #include "flags.h"
  32 #include "convert.h"
  33 #include "toplev.h"
  34 #include "langhooks.h"
  35 #include "real.h"
  36 /* Convert EXPR to some pointer or reference type TYPE.
  37
  38    EXPR must be pointer, reference, integer, enumeral, or literal zero;
  39    in other cases error is called.  */
  40
  41 tree
  42 convert_to_pointer (tree type, tree expr)
  43 {
  44   if (integer_zerop (expr))
  45     {
  46       expr = build_int_2 (0, 0);
  47       TREE_TYPE (expr) = type;
  48       return expr;
  49     }
  50
  51   switch (TREE_CODE (TREE_TYPE (expr)))
  52     {
  53     case POINTER_TYPE:
  54     case REFERENCE_TYPE:
  55       return build1 (NOP_EXPR, type, expr);
  56
  57     case INTEGER_TYPE:
  58     case ENUMERAL_TYPE:
  59     case BOOLEAN_TYPE:
  60     case CHAR_TYPE:
  61       if (TYPE_PRECISION (TREE_TYPE (expr)) == POINTER_SIZE)
  62         return build1 (CONVERT_EXPR, type, expr);
  63
  64       return
  65         convert_to_pointer (type,
  66                             convert ((*lang_hooks.types.type_for_size)
  67                                      (POINTER_SIZE, 0), expr));
  68
  69     default:
  70       error ("cannot convert to a pointer type");
  71       return convert_to_pointer (type, integer_zero_node);
  72     }
  73 }
  74
  75 /* Avoid any floating point extensions from EXP.  */
  76 tree
  77 strip_float_extensions (tree exp)
  78 {
  79   tree sub, expt, subt;
  80
  81   /*  For floating point constant look up the narrowest type that can hold
  82       it properly and handle it like (type)(narrowest_type)constant.
  83       This way we can optimize for instance a=a*2.0 where "a" is float
  84       but 2.0 is double constant.  */
  85   if (TREE_CODE (exp) == REAL_CST)
  86     {
  87       REAL_VALUE_TYPE orig;
  88       tree type = NULL;
  89
  90       orig = TREE_REAL_CST (exp);
  91       if (TYPE_PRECISION (TREE_TYPE (exp)) > TYPE_PRECISION (float_type_node)
  92           && exact_real_truncate (TYPE_MODE (float_type_node), &orig))
  93         type = float_type_node;
  94       else if (TYPE_PRECISION (TREE_TYPE (exp))
  95                > TYPE_PRECISION (double_type_node)
  96                && exact_real_truncate (TYPE_MODE (double_type_node), &orig))
  97         type = double_type_node;
  98       if (type)
  99         return build_real (type, real_value_truncate (TYPE_MODE (type), orig));
 100     }
 101
 102   if (TREE_CODE (exp) != NOP_EXPR)
 103     return exp;
 104
 105   sub = TREE_OPERAND (exp, 0);
 106   subt = TREE_TYPE (sub);
 107   expt = TREE_TYPE (exp);
 108
 109   if (!FLOAT_TYPE_P (subt))
 110     return exp;
 111
 112   if (TYPE_PRECISION (subt) > TYPE_PRECISION (expt))
 113     return exp;
 114
 115   return strip_float_extensions (sub);
 116 }
 117
 118
 119 /* Convert EXPR to some floating-point type TYPE.
 120
 121    EXPR must be float, integer, or enumeral;
 122    in other cases error is called.  */
 123
 124 tree
 125 convert_to_real (tree type, tree expr)
 126 {
 127   enum built_in_function fcode = builtin_mathfn_code (expr);
 128   tree itype = TREE_TYPE (expr);
 129
 130   /* Disable until we figure out how to decide whether the functions are
 131      present in runtime.  */
 132   /* Convert (float)sqrt((double)x) where x is float into sqrtf(x) */
 133   if (optimize
 134       && (fcode == BUILT_IN_SQRT
 135           || fcode == BUILT_IN_SQRTL
 136           || fcode == BUILT_IN_SIN
 137           || fcode == BUILT_IN_SINL
 138           || fcode == BUILT_IN_COS
 139           || fcode == BUILT_IN_COSL
 140           || fcode == BUILT_IN_EXP
 141           || fcode == BUILT_IN_EXPL
 142           || fcode == BUILT_IN_LOG
 143           || fcode == BUILT_IN_LOGL)
 144       && (TYPE_MODE (type) == TYPE_MODE (double_type_node)
 145           || TYPE_MODE (type) == TYPE_MODE (float_type_node)))
 146     {
 147       tree arg0 = strip_float_extensions (TREE_VALUE (TREE_OPERAND (expr, 1)));
 148       tree newtype = type;
 149
 150       /* We have (outertype)sqrt((innertype)x).  Choose the wider mode from
 151          the both as the safe type for operation.  */
 152       if (TYPE_PRECISION (TREE_TYPE (arg0)) > TYPE_PRECISION (type))
 153         newtype = TREE_TYPE (arg0);
 154
 155       /* Be careful about integer to fp conversions.
 156          These may overflow still.  */
 157       if (FLOAT_TYPE_P (TREE_TYPE (arg0))
 158           && TYPE_PRECISION (newtype) < TYPE_PRECISION (itype)
 159           && (TYPE_MODE (newtype) == TYPE_MODE (double_type_node)
 160               || TYPE_MODE (newtype) == TYPE_MODE (float_type_node)))
 161         {
 162           tree arglist;
 163           tree fn = mathfn_built_in (newtype, fcode);
 164
 165           if (fn)
 166             {
 167               arglist = build_tree_list (NULL_TREE, fold (convert_to_real (newtype, arg0)));
 168               expr = build_function_call_expr (fn, arglist);
 169               if (newtype == type)
 170                 return expr;
 171             }
 172         }
 173     }
 174   if (optimize
 175       && (((fcode == BUILT_IN_FLOORL
 176            || fcode == BUILT_IN_CEILL
 177            || fcode == BUILT_IN_ROUND
 178            || fcode == BUILT_IN_TRUNC
 179            || fcode == BUILT_IN_NEARBYINT)
 180           && (TYPE_MODE (type) == TYPE_MODE (double_type_node)
 181               || TYPE_MODE (type) == TYPE_MODE (float_type_node)))
 182           || ((fcode == BUILT_IN_FLOOR
 183                || fcode == BUILT_IN_CEIL
 184                || fcode == BUILT_IN_ROUND
 185                || fcode == BUILT_IN_TRUNC
 186                || fcode == BUILT_IN_NEARBYINT)
 187               && (TYPE_MODE (type) == TYPE_MODE (float_type_node)))))
 188     {
 189       tree fn = mathfn_built_in (type, fcode);
 190
 191       if (fn)
 192         {
 193           tree arg0 = strip_float_extensions (TREE_VALUE (TREE_OPERAND (expr,
 194                                                                         1)));
 195           tree arglist = build_tree_list (NULL_TREE,
 196                                           fold (convert_to_real (type, arg0)));
 197
 198           return build_function_call_expr (fn, arglist);
 199         }
 200     }
 201
 202   /* Propagate the cast into the operation.  */
 203   if (itype != type && FLOAT_TYPE_P (type))
 204     switch (TREE_CODE (expr))
 205       {
 206         /* convert (float)-x into -(float)x.  This is always safe.  */
 207         case ABS_EXPR:
 208         case NEGATE_EXPR:
 209           if (TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (expr)))
 210             return build1 (TREE_CODE (expr), type,
 211                            fold (convert_to_real (type,
 212                                                   TREE_OPERAND (expr, 0))));
 213           break;
 214         /* convert (outertype)((innertype0)a+(innertype1)b)
 215            into ((newtype)a+(newtype)b) where newtype
 216            is the widest mode from all of these.  */
 217         case PLUS_EXPR:
 218         case MINUS_EXPR:
 219         case MULT_EXPR:
 220         case RDIV_EXPR:
 221            {
 222              tree arg0 = strip_float_extensions (TREE_OPERAND (expr, 0));
 223              tree arg1 = strip_float_extensions (TREE_OPERAND (expr, 1));
 224
 225              if (FLOAT_TYPE_P (TREE_TYPE (arg0))
 226                  && FLOAT_TYPE_P (TREE_TYPE (arg1)))
 227                {
 228                   tree newtype = type;
 229                   if (TYPE_PRECISION (TREE_TYPE (arg0)) > TYPE_PRECISION (newtype))
 230                     newtype = TREE_TYPE (arg0);
 231                   if (TYPE_PRECISION (TREE_TYPE (arg1)) > TYPE_PRECISION (newtype))
 232                     newtype = TREE_TYPE (arg1);
 233                   if (TYPE_PRECISION (newtype) < TYPE_PRECISION (itype))
 234                     {
 235                       expr = build (TREE_CODE (expr), newtype,
 236                                     fold (convert_to_real (newtype, arg0)),
 237                                     fold (convert_to_real (newtype, arg1)));
 238                       if (newtype == type)
 239                         return expr;
 240                     }
 241                }
 242            }
 243           break;
 244         default:
 245           break;
 246       }
 247
 248   switch (TREE_CODE (TREE_TYPE (expr)))
 249     {
 250     case REAL_TYPE:
 251       return build1 (flag_float_store ? CONVERT_EXPR : NOP_EXPR,
 252                      type, expr);
 253
 254     case INTEGER_TYPE:
 255     case ENUMERAL_TYPE:
 256     case BOOLEAN_TYPE:
 257     case CHAR_TYPE:
 258       return build1 (FLOAT_EXPR, type, expr);
 259
 260     case COMPLEX_TYPE:
 261       return convert (type,
 262                       fold (build1 (REALPART_EXPR,
 263                                     TREE_TYPE (TREE_TYPE (expr)), expr)));
 264
 265     case POINTER_TYPE:
 266     case REFERENCE_TYPE:
 267       error ("pointer value used where a floating point value was expected");
 268       return convert_to_real (type, integer_zero_node);
 269
 270     default:
 271       error ("aggregate value used where a float was expected");
 272       return convert_to_real (type, integer_zero_node);
 273     }
 274 }
 275
 276 /* Convert EXPR to some integer (or enum) type TYPE.
 277
 278    EXPR must be pointer, integer, discrete (enum, char, or bool), float, or
 279    vector; in other cases error is called.
 280
 281    The result of this is always supposed to be a newly created tree node
 282    not in use in any existing structure.  */
 283
 284 tree
 285 convert_to_integer (tree type, tree expr)
 286 {
 287   enum tree_code ex_form = TREE_CODE (expr);
 288   tree intype = TREE_TYPE (expr);
 289   unsigned int inprec = TYPE_PRECISION (intype);
 290   unsigned int outprec = TYPE_PRECISION (type);
 291
 292   /* An INTEGER_TYPE cannot be incomplete, but an ENUMERAL_TYPE can
 293      be.  Consider `enum E = { a, b = (enum E) 3 };'.  */
 294   if (!COMPLETE_TYPE_P (type))
 295     {
 296       error ("conversion to incomplete type");
 297       return error_mark_node;
 298     }
 299
 300   switch (TREE_CODE (intype))
 301     {
 302     case POINTER_TYPE:
 303     case REFERENCE_TYPE:
 304       if (integer_zerop (expr))
 305         expr = integer_zero_node;
 306       else
 307         expr = fold (build1 (CONVERT_EXPR, (*lang_hooks.types.type_for_size)
 308                              (POINTER_SIZE, 0), expr));
 309
 310       return convert_to_integer (type, expr);
 311
 312     case INTEGER_TYPE:
 313     case ENUMERAL_TYPE:
 314     case BOOLEAN_TYPE:
 315     case CHAR_TYPE:
 316       /* If this is a logical operation, which just returns 0 or 1, we can
 317          change the type of the expression.  For some logical operations,
 318          we must also change the types of the operands to maintain type
 319          correctness.  */
 320
 321       if (TREE_CODE_CLASS (ex_form) == '<')
 322         {
 323           TREE_TYPE (expr) = type;
 324           return expr;
 325         }
 326
 327       else if (ex_form == TRUTH_AND_EXPR || ex_form == TRUTH_ANDIF_EXPR
 328                || ex_form == TRUTH_OR_EXPR || ex_form == TRUTH_ORIF_EXPR
 329                || ex_form == TRUTH_XOR_EXPR)
 330         {
 331           TREE_OPERAND (expr, 0) = convert (type, TREE_OPERAND (expr, 0));
 332           TREE_OPERAND (expr, 1) = convert (type, TREE_OPERAND (expr, 1));
 333           TREE_TYPE (expr) = type;
 334           return expr;
 335         }
 336
 337       else if (ex_form == TRUTH_NOT_EXPR)
 338         {
 339           TREE_OPERAND (expr, 0) = convert (type, TREE_OPERAND (expr, 0));
 340           TREE_TYPE (expr) = type;
 341           return expr;
 342         }
 343
 344       /* If we are widening the type, put in an explicit conversion.
 345          Similarly if we are not changing the width.  After this, we know
 346          we are truncating EXPR.  */
 347
 348       else if (outprec >= inprec)
 349         return build1 (NOP_EXPR, type, expr);
 350
 351       /* If TYPE is an enumeral type or a type with a precision less
 352          than the number of bits in its mode, do the conversion to the
 353          type corresponding to its mode, then do a nop conversion
 354          to TYPE.  */
 355       else if (TREE_CODE (type) == ENUMERAL_TYPE
 356                || outprec != GET_MODE_BITSIZE (TYPE_MODE (type)))
 357         return build1 (NOP_EXPR, type,
 358                        convert ((*lang_hooks.types.type_for_mode)
 359                                 (TYPE_MODE (type), TREE_UNSIGNED (type)),
 360                                 expr));
 361
 362       /* Here detect when we can distribute the truncation down past some
 363          arithmetic.  For example, if adding two longs and converting to an
 364          int, we can equally well convert both to ints and then add.
 365          For the operations handled here, such truncation distribution
 366          is always safe.
 367          It is desirable in these cases:
 368          1) when truncating down to full-word from a larger size
 369          2) when truncating takes no work.
 370          3) when at least one operand of the arithmetic has been extended
 371          (as by C's default conversions).  In this case we need two conversions
 372          if we do the arithmetic as already requested, so we might as well
 373          truncate both and then combine.  Perhaps that way we need only one.
 374
 375          Note that in general we cannot do the arithmetic in a type
 376          shorter than the desired result of conversion, even if the operands
 377          are both extended from a shorter type, because they might overflow
 378          if combined in that type.  The exceptions to this--the times when
 379          two narrow values can be combined in their narrow type even to
 380          make a wider result--are handled by "shorten" in build_binary_op.  */
 381
 382       switch (ex_form)
 383         {
 384         case RSHIFT_EXPR:
 385           /* We can pass truncation down through right shifting
 386              when the shift count is a nonpositive constant.  */
 387           if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST
 388               && tree_int_cst_lt (TREE_OPERAND (expr, 1),
 389                                   convert (TREE_TYPE (TREE_OPERAND (expr, 1)),
 390                                            integer_one_node)))
 391             goto trunc1;
 392           break;
 393
 394         case LSHIFT_EXPR:
 395           /* We can pass truncation down through left shifting
 396              when the shift count is a nonnegative constant and
 397              the target type is unsigned.  */
 398           if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST
 399               && tree_int_cst_sgn (TREE_OPERAND (expr, 1)) >= 0
 400               && TREE_UNSIGNED (type)
 401               && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
 402             {
 403               /* If shift count is less than the width of the truncated type,
 404                  really shift.  */
 405               if (tree_int_cst_lt (TREE_OPERAND (expr, 1), TYPE_SIZE (type)))
 406                 /* In this case, shifting is like multiplication.  */
 407                 goto trunc1;
 408               else
 409                 {
 410                   /* If it is >= that width, result is zero.
 411                      Handling this with trunc1 would give the wrong result:
 412                      (int) ((long long) a << 32) is well defined (as 0)
 413                      but (int) a << 32 is undefined and would get a
 414                      warning.  */
 415
 416                   tree t = convert_to_integer (type, integer_zero_node);
 417
 418                   /* If the original expression had side-effects, we must
 419                      preserve it.  */
 420                   if (TREE_SIDE_EFFECTS (expr))
 421                     return build (COMPOUND_EXPR, type, expr, t);
 422                   else
 423                     return t;
 424                 }
 425             }
 426           break;
 427
 428         case MAX_EXPR:
 429         case MIN_EXPR:
 430         case MULT_EXPR:
 431           {
 432             tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type);
 433             tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type);
 434
 435             /* Don't distribute unless the output precision is at least as big
 436                as the actual inputs.  Otherwise, the comparison of the
 437                truncated values will be wrong.  */
 438             if (outprec >= TYPE_PRECISION (TREE_TYPE (arg0))
 439                 && outprec >= TYPE_PRECISION (TREE_TYPE (arg1))
 440                 /* If signedness of arg0 and arg1 don't match,
 441                    we can't necessarily find a type to compare them in.  */
 442                 && (TREE_UNSIGNED (TREE_TYPE (arg0))
 443                     == TREE_UNSIGNED (TREE_TYPE (arg1))))
 444               goto trunc1;
 445             break;
 446           }
 447
 448         case PLUS_EXPR:
 449         case MINUS_EXPR:
 450         case BIT_AND_EXPR:
 451         case BIT_IOR_EXPR:
 452         case BIT_XOR_EXPR:
 453         case BIT_ANDTC_EXPR:
 454         trunc1:
 455           {
 456             tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type);
 457             tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type);
 458
 459             if (outprec >= BITS_PER_WORD
 460                 || TRULY_NOOP_TRUNCATION (outprec, inprec)
 461                 || inprec > TYPE_PRECISION (TREE_TYPE (arg0))
 462                 || inprec > TYPE_PRECISION (TREE_TYPE (arg1)))
 463               {
 464                 /* Do the arithmetic in type TYPEX,
 465                    then convert result to TYPE.  */
 466                 tree typex = type;
 467
 468                 /* Can't do arithmetic in enumeral types
 469                    so use an integer type that will hold the values.  */
 470                 if (TREE_CODE (typex) == ENUMERAL_TYPE)
 471                   typex = (*lang_hooks.types.type_for_size)
 472                     (TYPE_PRECISION (typex), TREE_UNSIGNED (typex));
 473
 474                 /* But now perhaps TYPEX is as wide as INPREC.
 475                    In that case, do nothing special here.
 476                    (Otherwise would recurse infinitely in convert.  */
 477                 if (TYPE_PRECISION (typex) != inprec)
 478                   {
 479                     /* Don't do unsigned arithmetic where signed was wanted,
 480                        or vice versa.
 481                        Exception: if both of the original operands were
 482                        unsigned then we can safely do the work as unsigned.
 483                        Exception: shift operations take their type solely
 484                        from the first argument.
 485                        Exception: the LSHIFT_EXPR case above requires that
 486                        we perform this operation unsigned lest we produce
 487                        signed-overflow undefinedness.
 488                        And we may need to do it as unsigned
 489                        if we truncate to the original size.  */
 490                     if (TREE_UNSIGNED (TREE_TYPE (expr))
 491                         || (TREE_UNSIGNED (TREE_TYPE (arg0))
 492                             && (TREE_UNSIGNED (TREE_TYPE (arg1))
 493                                 || ex_form == LSHIFT_EXPR
 494                                 || ex_form == RSHIFT_EXPR
 495                                 || ex_form == LROTATE_EXPR
 496                                 || ex_form == RROTATE_EXPR))
 497                         || ex_form == LSHIFT_EXPR)
 498                       typex = (*lang_hooks.types.unsigned_type) (typex);
 499                     else
 500                       typex = (*lang_hooks.types.signed_type) (typex);
 501                     return convert (type,
 502                                     fold (build (ex_form, typex,
 503                                                  convert (typex, arg0),
 504                                                  convert (typex, arg1),
 505                                                  0)));
 506                   }
 507               }
 508           }
 509           break;
 510
 511         case NEGATE_EXPR:
 512         case BIT_NOT_EXPR:
 513           /* This is not correct for ABS_EXPR,
 514              since we must test the sign before truncation.  */
 515           {
 516             tree typex = type;
 517
 518             /* Can't do arithmetic in enumeral types
 519                so use an integer type that will hold the values.  */
 520             if (TREE_CODE (typex) == ENUMERAL_TYPE)
 521               typex = (*lang_hooks.types.type_for_size)
 522                 (TYPE_PRECISION (typex), TREE_UNSIGNED (typex));
 523
 524             /* But now perhaps TYPEX is as wide as INPREC.
 525                In that case, do nothing special here.
 526                (Otherwise would recurse infinitely in convert.  */
 527             if (TYPE_PRECISION (typex) != inprec)
 528               {
 529                 /* Don't do unsigned arithmetic where signed was wanted,
 530                    or vice versa.  */
 531                 if (TREE_UNSIGNED (TREE_TYPE (expr)))
 532                   typex = (*lang_hooks.types.unsigned_type) (typex);
 533                 else
 534                   typex = (*lang_hooks.types.signed_type) (typex);
 535                 return convert (type,
 536                                 fold (build1 (ex_form, typex,
 537                                               convert (typex,
 538                                                        TREE_OPERAND (expr, 0)))));
 539               }
 540           }
 541
 542         case NOP_EXPR:
 543           /* Don't introduce a
 544              "can't convert between vector values of different size" error.  */
 545           if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == VECTOR_TYPE
 546               && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_OPERAND (expr, 0))))
 547                   != GET_MODE_SIZE (TYPE_MODE (type))))
 548             break;
 549           /* If truncating after truncating, might as well do all at once.
 550              If truncating after extending, we may get rid of wasted work.  */
 551           return convert (type, get_unwidened (TREE_OPERAND (expr, 0), type));
 552
 553         case COND_EXPR:
 554           /* It is sometimes worthwhile to push the narrowing down through
 555              the conditional and never loses.  */
 556           return fold (build (COND_EXPR, type, TREE_OPERAND (expr, 0),
 557                               convert (type, TREE_OPERAND (expr, 1)),
 558                               convert (type, TREE_OPERAND (expr, 2))));
 559
 560         default:
 561           break;
 562         }
 563
 564       return build1 (NOP_EXPR, type, expr);
 565
 566     case REAL_TYPE:
 567       return build1 (FIX_TRUNC_EXPR, type, expr);
 568
 569     case COMPLEX_TYPE:
 570       return convert (type,
 571                       fold (build1 (REALPART_EXPR,
 572                                     TREE_TYPE (TREE_TYPE (expr)), expr)));
 573
 574     case VECTOR_TYPE:
 575       if (GET_MODE_SIZE (TYPE_MODE (type))
 576           != GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (expr))))
 577         {
 578           error ("can't convert between vector values of different size");
 579           return error_mark_node;
 580         }
 581       return build1 (NOP_EXPR, type, expr);
 582
 583     default:
 584       error ("aggregate value used where an integer was expected");
 585       return convert (type, integer_zero_node);
 586     }
 587 }
 588
 589 /* Convert EXPR to the complex type TYPE in the usual ways.  */
 590
 591 tree
 592 convert_to_complex (tree type, tree expr)
 593 {
 594   tree subtype = TREE_TYPE (type);
 595
 596   switch (TREE_CODE (TREE_TYPE (expr)))
 597     {
 598     case REAL_TYPE:
 599     case INTEGER_TYPE:
 600     case ENUMERAL_TYPE:
 601     case BOOLEAN_TYPE:
 602     case CHAR_TYPE:
 603       return build (COMPLEX_EXPR, type, convert (subtype, expr),
 604                     convert (subtype, integer_zero_node));
 605
 606     case COMPLEX_TYPE:
 607       {
 608         tree elt_type = TREE_TYPE (TREE_TYPE (expr));
 609
 610         if (TYPE_MAIN_VARIANT (elt_type) == TYPE_MAIN_VARIANT (subtype))
 611           return expr;
 612         else if (TREE_CODE (expr) == COMPLEX_EXPR)
 613           return fold (build (COMPLEX_EXPR,
 614                               type,
 615                               convert (subtype, TREE_OPERAND (expr, 0)),
 616                               convert (subtype, TREE_OPERAND (expr, 1))));
 617         else
 618           {
 619             expr = save_expr (expr);
 620             return
 621               fold (build (COMPLEX_EXPR,
 622                            type, convert (subtype,
 623                                           fold (build1 (REALPART_EXPR,
 624                                                         TREE_TYPE (TREE_TYPE (expr)),
 625                                                         expr))),
 626                            convert (subtype,
 627                                     fold (build1 (IMAGPART_EXPR,
 628                                                   TREE_TYPE (TREE_TYPE (expr)),
 629                                                   expr)))));
 630           }
 631       }
 632
 633     case POINTER_TYPE:
 634     case REFERENCE_TYPE:
 635       error ("pointer value used where a complex was expected");
 636       return convert_to_complex (type, integer_zero_node);
 637
 638     default:
 639       error ("aggregate value used where a complex was expected");
 640       return convert_to_complex (type, integer_zero_node);
 641     }
 642 }
 643
 644 /* Convert EXPR to the vector type TYPE in the usual ways.  */
 645
 646 tree
 647 convert_to_vector (tree type, tree expr)
 648 {
 649   switch (TREE_CODE (TREE_TYPE (expr)))
 650     {
 651     case INTEGER_TYPE:
 652     case VECTOR_TYPE:
 653       if (GET_MODE_SIZE (TYPE_MODE (type))
 654           != GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (expr))))
 655         {
 656           error ("can't convert between vector values of different size");
 657           return error_mark_node;
 658         }
 659       return build1 (NOP_EXPR, type, expr);
 660
 661     default:
 662       error ("can't convert value to a vector");
 663       return convert_to_vector (type, integer_zero_node);
 664     }
 665 }