gcc/convert.cc

   1 /* Utility routines for data type conversion for GCC.
   2    Copyright (C) 1987-2023 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20
  21 /* These routines are somewhat language-independent utility function
  22    intended to be called by the language-specific convert () functions.  */
  23
  24 #include "config.h"
  25 #include "system.h"
  26 #include "coretypes.h"
  27 #include "target.h"
  28 #include "tree.h"
  29 #include "diagnostic-core.h"
  30 #include "fold-const.h"
  31 #include "stor-layout.h"
  32 #include "convert.h"
  33 #include "langhooks.h"
  34 #include "builtins.h"
  35 #include "ubsan.h"
  36 #include "stringpool.h"
  37 #include "attribs.h"
  38 #include "asan.h"
  39 #include "selftest.h"
  40
  41 #define maybe_fold_build1_loc(FOLD_P, LOC, CODE, TYPE, EXPR) \
  42   ((FOLD_P) ? fold_build1_loc (LOC, CODE, TYPE, EXPR)        \
  43    : build1_loc (LOC, CODE, TYPE, EXPR))
  44 #define maybe_fold_build2_loc(FOLD_P, LOC, CODE, TYPE, EXPR1, EXPR2) \
  45   ((FOLD_P) ? fold_build2_loc (LOC, CODE, TYPE, EXPR1, EXPR2)        \
  46    : build2_loc (LOC, CODE, TYPE, EXPR1, EXPR2))
  47
  48 /* Convert EXPR to some pointer or reference type TYPE.
  49    EXPR must be pointer, reference, integer, enumeral, or literal zero;
  50    in other cases error is called.  If FOLD_P is true, try to fold the
  51    expression.  */
  52
  53 static tree
  54 convert_to_pointer_1 (tree type, tree expr, bool fold_p)
  55 {
  56   location_t loc = EXPR_LOCATION (expr);
  57   if (TREE_TYPE (expr) == type)
  58     return expr;
  59
  60   switch (TREE_CODE (TREE_TYPE (expr)))
  61     {
  62     case POINTER_TYPE:
  63     case REFERENCE_TYPE:
  64       {
  65         /* If the pointers point to different address spaces, conversion needs
  66            to be done via a ADDR_SPACE_CONVERT_EXPR instead of a NOP_EXPR.  */
  67         addr_space_t to_as = TYPE_ADDR_SPACE (TREE_TYPE (type));
  68         addr_space_t from_as = TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (expr)));
  69
  70         if (to_as == from_as)
  71           return maybe_fold_build1_loc (fold_p, loc, NOP_EXPR, type, expr);
  72         else
  73           return maybe_fold_build1_loc (fold_p, loc, ADDR_SPACE_CONVERT_EXPR,
  74                                         type, expr);
  75       }
  76
  77     case INTEGER_TYPE:
  78     case ENUMERAL_TYPE:
  79     case BOOLEAN_TYPE:
  80     case BITINT_TYPE:
  81       {
  82         /* If the input precision differs from the target pointer type
  83            precision, first convert the input expression to an integer type of
  84            the target precision.  Some targets, e.g. VMS, need several pointer
  85            sizes to coexist so the latter isn't necessarily POINTER_SIZE.  */
  86         unsigned int pprec = TYPE_PRECISION (type);
  87         unsigned int eprec = TYPE_PRECISION (TREE_TYPE (expr));
  88
  89         if (eprec != pprec)
  90           expr
  91             = maybe_fold_build1_loc (fold_p, loc, NOP_EXPR,
  92                                      lang_hooks.types.type_for_size (pprec, 0),
  93                                      expr);
  94       }
  95       return maybe_fold_build1_loc (fold_p, loc, CONVERT_EXPR, type, expr);
  96
  97     default:
  98       error ("cannot convert to a pointer type");
  99       return error_mark_node;
 100     }
 101 }
 102
 103 /* Subroutine of the various convert_to_*_maybe_fold routines.
 104
 105    If a location wrapper has been folded to a constant (presumably of
 106    a different type), re-wrap the new constant with a location wrapper.  */
 107
 108 tree
 109 preserve_any_location_wrapper (tree result, tree orig_expr)
 110 {
 111   if (CONSTANT_CLASS_P (result) && location_wrapper_p (orig_expr))
 112     {
 113       if (result == TREE_OPERAND (orig_expr, 0))
 114         return orig_expr;
 115       else
 116         return maybe_wrap_with_location (result, EXPR_LOCATION (orig_expr));
 117     }
 118
 119   return result;
 120 }
 121
 122 /* A wrapper around convert_to_pointer_1 that always folds the
 123    expression.  */
 124
 125 tree
 126 convert_to_pointer (tree type, tree expr)
 127 {
 128   return convert_to_pointer_1 (type, expr, true);
 129 }
 130
 131 /* A wrapper around convert_to_pointer_1 that only folds the
 132    expression if DOFOLD, or if it is CONSTANT_CLASS_OR_WRAPPER_P.  */
 133
 134 tree
 135 convert_to_pointer_maybe_fold (tree type, tree expr, bool dofold)
 136 {
 137   tree result
 138     = convert_to_pointer_1 (type, expr,
 139                             dofold || CONSTANT_CLASS_OR_WRAPPER_P (expr));
 140   return preserve_any_location_wrapper (result, expr);
 141 }
 142
 143 /* Convert EXPR to some floating-point type TYPE.
 144
 145    EXPR must be float, fixed-point, integer, or enumeral;
 146    in other cases error is called.  If FOLD_P is true, try to fold
 147    the expression.  */
 148
 149 static tree
 150 convert_to_real_1 (tree type, tree expr, bool fold_p)
 151 {
 152   enum built_in_function fcode = builtin_mathfn_code (expr);
 153   tree itype = TREE_TYPE (expr);
 154   location_t loc = EXPR_LOCATION (expr);
 155
 156   if (TREE_CODE (expr) == COMPOUND_EXPR)
 157     {
 158       tree t = convert_to_real_1 (type, TREE_OPERAND (expr, 1), fold_p);
 159       if (t == TREE_OPERAND (expr, 1))
 160         return expr;
 161       return build2_loc (EXPR_LOCATION (expr), COMPOUND_EXPR, TREE_TYPE (t),
 162                          TREE_OPERAND (expr, 0), t);
 163     }
 164
 165   /* Disable until we figure out how to decide whether the functions are
 166      present in runtime.  */
 167   /* Convert (float)sqrt((double)x) where x is float into sqrtf(x) */
 168   if (optimize
 169       && (TYPE_MODE (type) == TYPE_MODE (double_type_node)
 170           || TYPE_MODE (type) == TYPE_MODE (float_type_node)))
 171     {
 172       switch (fcode)
 173         {
 174 #define CASE_MATHFN(FN) case BUILT_IN_##FN: case BUILT_IN_##FN##L:
 175           CASE_MATHFN (COSH)
 176           CASE_MATHFN (EXP)
 177           CASE_MATHFN (EXP10)
 178           CASE_MATHFN (EXP2)
 179           CASE_MATHFN (EXPM1)
 180           CASE_MATHFN (GAMMA)
 181           CASE_MATHFN (J0)
 182           CASE_MATHFN (J1)
 183           CASE_MATHFN (LGAMMA)
 184           CASE_MATHFN (POW10)
 185           CASE_MATHFN (SINH)
 186           CASE_MATHFN (TGAMMA)
 187           CASE_MATHFN (Y0)
 188           CASE_MATHFN (Y1)
 189             /* The above functions may set errno differently with float
 190                input or output so this transformation is not safe with
 191                -fmath-errno.  */
 192             if (flag_errno_math)
 193               break;
 194             gcc_fallthrough ();
 195           CASE_MATHFN (ACOS)
 196           CASE_MATHFN (ACOSH)
 197           CASE_MATHFN (ASIN)
 198           CASE_MATHFN (ASINH)
 199           CASE_MATHFN (ATAN)
 200           CASE_MATHFN (ATANH)
 201           CASE_MATHFN (CBRT)
 202           CASE_MATHFN (COS)
 203           CASE_MATHFN (ERF)
 204           CASE_MATHFN (ERFC)
 205           CASE_MATHFN (LOG)
 206           CASE_MATHFN (LOG10)
 207           CASE_MATHFN (LOG2)
 208           CASE_MATHFN (LOG1P)
 209           CASE_MATHFN (SIN)
 210           CASE_MATHFN (TAN)
 211           CASE_MATHFN (TANH)
 212             /* The above functions are not safe to do this conversion.  */
 213             if (!flag_unsafe_math_optimizations)
 214               break;
 215             gcc_fallthrough ();
 216           CASE_MATHFN (SQRT)
 217           CASE_MATHFN (FABS)
 218           CASE_MATHFN (LOGB)
 219 #undef CASE_MATHFN
 220             if (call_expr_nargs (expr) != 1
 221                 || !SCALAR_FLOAT_TYPE_P (TREE_TYPE (CALL_EXPR_ARG (expr, 0))))
 222               break;
 223             {
 224               tree arg0 = strip_float_extensions (CALL_EXPR_ARG (expr, 0));
 225               tree newtype = type;
 226
 227               /* We have (outertype)sqrt((innertype)x).  Choose the wider mode
 228                  from the both as the safe type for operation.  */
 229               if (TYPE_PRECISION (TREE_TYPE (arg0)) > TYPE_PRECISION (type))
 230                 newtype = TREE_TYPE (arg0);
 231
 232               /* We consider to convert
 233
 234                      (T1) sqrtT2 ((T2) exprT3)
 235                  to
 236                      (T1) sqrtT4 ((T4) exprT3)
 237
 238                   , where T1 is TYPE, T2 is ITYPE, T3 is TREE_TYPE (ARG0),
 239                  and T4 is NEWTYPE.  All those types are of floating-point types.
 240                  T4 (NEWTYPE) should be narrower than T2 (ITYPE). This conversion
 241                  is safe only if P1 >= P2*2+2, where P1 and P2 are precisions of
 242                  T2 and T4.  See the following URL for a reference:
 243                  http://stackoverflow.com/questions/9235456/determining-
 244                  floating-point-square-root
 245                  */
 246               if ((fcode == BUILT_IN_SQRT || fcode == BUILT_IN_SQRTL)
 247                   && !flag_unsafe_math_optimizations)
 248                 {
 249                   /* The following conversion is unsafe even the precision condition
 250                      below is satisfied:
 251
 252                      (float) sqrtl ((long double) double_val) -> (float) sqrt (double_val)
 253                     */
 254                   if (TYPE_MODE (type) != TYPE_MODE (newtype))
 255                     break;
 256
 257                   int p1 = REAL_MODE_FORMAT (TYPE_MODE (itype))->p;
 258                   int p2 = REAL_MODE_FORMAT (TYPE_MODE (newtype))->p;
 259                   if (p1 < p2 * 2 + 2)
 260                     break;
 261                 }
 262
 263               /* Be careful about integer to fp conversions.
 264                  These may overflow still.  */
 265               if (FLOAT_TYPE_P (TREE_TYPE (arg0))
 266                   && TYPE_PRECISION (newtype) < TYPE_PRECISION (itype)
 267                   && (TYPE_MODE (newtype) == TYPE_MODE (double_type_node)
 268                       || TYPE_MODE (newtype) == TYPE_MODE (float_type_node)))
 269                 {
 270                   tree fn = mathfn_built_in (newtype, fcode);
 271                   if (fn)
 272                     {
 273                       tree arg = convert_to_real_1 (newtype, arg0, fold_p);
 274                       expr = build_call_expr (fn, 1, arg);
 275                       if (newtype == type)
 276                         return expr;
 277                     }
 278                 }
 279             }
 280         default:
 281           break;
 282         }
 283     }
 284
 285   /* Propagate the cast into the operation.  */
 286   if (itype != type && FLOAT_TYPE_P (type))
 287     switch (TREE_CODE (expr))
 288       {
 289         /* Convert (float)-x into -(float)x.  This is safe for
 290            round-to-nearest rounding mode when the inner type is float.  */
 291         case ABS_EXPR:
 292         case NEGATE_EXPR:
 293           if (!flag_rounding_math
 294               && FLOAT_TYPE_P (itype)
 295               && TYPE_PRECISION (type) < TYPE_PRECISION (itype))
 296             {
 297               tree arg = convert_to_real_1 (type, TREE_OPERAND (expr, 0),
 298                                             fold_p);
 299               return build1 (TREE_CODE (expr), type, arg);
 300             }
 301           break;
 302         default:
 303           break;
 304       }
 305
 306   switch (TREE_CODE (TREE_TYPE (expr)))
 307     {
 308     case REAL_TYPE:
 309       /* Ignore the conversion if we don't need to store intermediate
 310          results and neither type is a decimal float.  */
 311       return build1_loc (loc,
 312                          (flag_float_store
 313                           || DECIMAL_FLOAT_TYPE_P (type)
 314                           || DECIMAL_FLOAT_TYPE_P (itype))
 315                          ? CONVERT_EXPR : NOP_EXPR, type, expr);
 316
 317     case INTEGER_TYPE:
 318     case ENUMERAL_TYPE:
 319     case BOOLEAN_TYPE:
 320     case BITINT_TYPE:
 321       return build1 (FLOAT_EXPR, type, expr);
 322
 323     case FIXED_POINT_TYPE:
 324       return build1 (FIXED_CONVERT_EXPR, type, expr);
 325
 326     case COMPLEX_TYPE:
 327       return convert (type,
 328                       maybe_fold_build1_loc (fold_p, loc, REALPART_EXPR,
 329                                              TREE_TYPE (TREE_TYPE (expr)),
 330                                              expr));
 331
 332     case POINTER_TYPE:
 333     case REFERENCE_TYPE:
 334       error ("pointer value used where a floating-point was expected");
 335       return error_mark_node;
 336
 337     default:
 338       error ("aggregate value used where a floating-point was expected");
 339       return error_mark_node;
 340     }
 341 }
 342
 343 /* A wrapper around convert_to_real_1 that always folds the
 344    expression.  */
 345
 346 tree
 347 convert_to_real (tree type, tree expr)
 348 {
 349   return convert_to_real_1 (type, expr, true);
 350 }
 351
 352 /* A wrapper around convert_to_real_1 that only folds the
 353    expression if DOFOLD, or if it is CONSTANT_CLASS_OR_WRAPPER_P.  */
 354
 355 tree
 356 convert_to_real_maybe_fold (tree type, tree expr, bool dofold)
 357 {
 358   tree result
 359     = convert_to_real_1 (type, expr,
 360                          dofold || CONSTANT_CLASS_OR_WRAPPER_P (expr));
 361   return preserve_any_location_wrapper (result, expr);
 362 }
 363
 364 /* Try to narrow EX_FORM ARG0 ARG1 in narrowed arg types producing a
 365    result in TYPE.  */
 366
 367 static tree
 368 do_narrow (location_t loc,
 369            enum tree_code ex_form, tree type, tree arg0, tree arg1,
 370            tree expr, unsigned inprec, unsigned outprec, bool dofold)
 371 {
 372   /* Do the arithmetic in type TYPEX,
 373      then convert result to TYPE.  */
 374   tree typex = type;
 375
 376   /* Can't do arithmetic in enumeral types
 377      so use an integer type that will hold the values.  */
 378   if (TREE_CODE (typex) == ENUMERAL_TYPE)
 379     typex = lang_hooks.types.type_for_size (TYPE_PRECISION (typex),
 380                                             TYPE_UNSIGNED (typex));
 381
 382   /* The type demotion below might cause doing unsigned arithmetic
 383      instead of signed, and thus hide overflow bugs.  */
 384   if ((ex_form == PLUS_EXPR || ex_form == MINUS_EXPR)
 385       && !TYPE_UNSIGNED (typex)
 386       && sanitize_flags_p (SANITIZE_SI_OVERFLOW))
 387     return NULL_TREE;
 388
 389   /* Similarly for multiplication, but in that case it can be
 390      problematic even if typex is unsigned type - 0xffff * 0xffff
 391      overflows in int.  */
 392   if (ex_form == MULT_EXPR
 393       && !TYPE_OVERFLOW_WRAPS (TREE_TYPE (expr))
 394       && sanitize_flags_p (SANITIZE_SI_OVERFLOW))
 395     return NULL_TREE;
 396
 397   /* But now perhaps TYPEX is as wide as INPREC.
 398      In that case, do nothing special here.
 399      (Otherwise would recurse infinitely in convert.  */
 400   if (TYPE_PRECISION (typex) != inprec)
 401     {
 402       /* Don't do unsigned arithmetic where signed was wanted,
 403          or vice versa.
 404          Exception: if both of the original operands were
 405          unsigned then we can safely do the work as unsigned.
 406          Exception: shift operations take their type solely
 407          from the first argument.
 408          Exception: the LSHIFT_EXPR case above requires that
 409          we perform this operation unsigned lest we produce
 410          signed-overflow undefinedness.
 411          And we may need to do it as unsigned
 412          if we truncate to the original size.  */
 413       if (TYPE_UNSIGNED (TREE_TYPE (expr))
 414           || (TYPE_UNSIGNED (TREE_TYPE (arg0))
 415               && (TYPE_UNSIGNED (TREE_TYPE (arg1))
 416                   || ex_form == LSHIFT_EXPR
 417                   || ex_form == RSHIFT_EXPR
 418                   || ex_form == LROTATE_EXPR
 419                   || ex_form == RROTATE_EXPR))
 420           || ex_form == LSHIFT_EXPR
 421           /* If we have !flag_wrapv, and either ARG0 or
 422              ARG1 is of a signed type, we have to do
 423              PLUS_EXPR, MINUS_EXPR or MULT_EXPR in an unsigned
 424              type in case the operation in outprec precision
 425              could overflow.  Otherwise, we would introduce
 426              signed-overflow undefinedness.  */
 427           || ((!(INTEGRAL_TYPE_P (TREE_TYPE (arg0))
 428                  && TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0)))
 429                || !(INTEGRAL_TYPE_P (TREE_TYPE (arg1))
 430                     && TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg1))))
 431               && ((TYPE_PRECISION (TREE_TYPE (arg0)) * 2u
 432                    > outprec)
 433                   || (TYPE_PRECISION (TREE_TYPE (arg1)) * 2u
 434                       > outprec))
 435               && (ex_form == PLUS_EXPR
 436                   || ex_form == MINUS_EXPR
 437                   || ex_form == MULT_EXPR)))
 438         {
 439           if (!TYPE_UNSIGNED (typex))
 440             typex = unsigned_type_for (typex);
 441         }
 442       else
 443         {
 444           if (TYPE_UNSIGNED (typex))
 445             typex = signed_type_for (typex);
 446         }
 447       /* We should do away with all this once we have a proper
 448          type promotion/demotion pass, see PR45397.  */
 449       expr = maybe_fold_build2_loc (dofold, loc, ex_form, typex,
 450                                     convert (typex, arg0),
 451                                     convert (typex, arg1));
 452       return convert (type, expr);
 453     }
 454
 455   return NULL_TREE;
 456 }
 457
 458 /* Convert EXPR to some integer (or enum) type TYPE.
 459
 460    EXPR must be pointer, integer, discrete (enum, char, or bool), float,
 461    fixed-point or vector; in other cases error is called.
 462
 463    If DOFOLD is TRUE, we try to simplify newly-created patterns by folding.
 464
 465    The result of this is always supposed to be a newly created tree node
 466    not in use in any existing structure.  */
 467
 468 static tree
 469 convert_to_integer_1 (tree type, tree expr, bool dofold)
 470 {
 471   enum tree_code ex_form = TREE_CODE (expr);
 472   tree intype = TREE_TYPE (expr);
 473   unsigned int inprec = element_precision (intype);
 474   unsigned int outprec = element_precision (type);
 475   location_t loc = EXPR_LOCATION (expr);
 476
 477   /* An INTEGER_TYPE cannot be incomplete, but an ENUMERAL_TYPE can
 478      be.  Consider `enum E = { a, b = (enum E) 3 };'.  */
 479   if (!COMPLETE_TYPE_P (type))
 480     {
 481       error ("conversion to incomplete type");
 482       return error_mark_node;
 483     }
 484
 485   if (ex_form == COMPOUND_EXPR)
 486     {
 487       tree t = convert_to_integer_1 (type, TREE_OPERAND (expr, 1), dofold);
 488       if (t == TREE_OPERAND (expr, 1))
 489         return expr;
 490       return build2_loc (EXPR_LOCATION (expr), COMPOUND_EXPR, TREE_TYPE (t),
 491                          TREE_OPERAND (expr, 0), t);
 492     }
 493
 494   /* Convert e.g. (long)round(d) -> lround(d).  */
 495   /* If we're converting to char, we may encounter differing behavior
 496      between converting from double->char vs double->long->char.
 497      We're in "undefined" territory but we prefer to be conservative,
 498      so only proceed in "unsafe" math mode.  */
 499   if (optimize
 500       && (flag_unsafe_math_optimizations
 501           || (long_integer_type_node
 502               && outprec >= TYPE_PRECISION (long_integer_type_node))))
 503     {
 504       tree s_expr = strip_float_extensions (expr);
 505       tree s_intype = TREE_TYPE (s_expr);
 506       const enum built_in_function fcode = builtin_mathfn_code (s_expr);
 507       tree fn = 0;
 508
 509       switch (fcode)
 510         {
 511         CASE_FLT_FN (BUILT_IN_CEIL):
 512         CASE_FLT_FN_FLOATN_NX (BUILT_IN_CEIL):
 513           /* Only convert in ISO C99 mode.  */
 514           if (!targetm.libc_has_function (function_c99_misc, intype))
 515             break;
 516           if (outprec < TYPE_PRECISION (integer_type_node)
 517               || (outprec == TYPE_PRECISION (integer_type_node)
 518                   && !TYPE_UNSIGNED (type)))
 519             fn = mathfn_built_in (s_intype, BUILT_IN_ICEIL);
 520           else if (outprec == TYPE_PRECISION (long_integer_type_node)
 521                    && !TYPE_UNSIGNED (type))
 522             fn = mathfn_built_in (s_intype, BUILT_IN_LCEIL);
 523           else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
 524                    && !TYPE_UNSIGNED (type))
 525             fn = mathfn_built_in (s_intype, BUILT_IN_LLCEIL);
 526           break;
 527
 528         CASE_FLT_FN (BUILT_IN_FLOOR):
 529         CASE_FLT_FN_FLOATN_NX (BUILT_IN_FLOOR):
 530           /* Only convert in ISO C99 mode.  */
 531           if (!targetm.libc_has_function (function_c99_misc, intype))
 532             break;
 533           if (outprec < TYPE_PRECISION (integer_type_node)
 534               || (outprec == TYPE_PRECISION (integer_type_node)
 535                   && !TYPE_UNSIGNED (type)))
 536             fn = mathfn_built_in (s_intype, BUILT_IN_IFLOOR);
 537           else if (outprec == TYPE_PRECISION (long_integer_type_node)
 538                    && !TYPE_UNSIGNED (type))
 539             fn = mathfn_built_in (s_intype, BUILT_IN_LFLOOR);
 540           else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
 541                    && !TYPE_UNSIGNED (type))
 542             fn = mathfn_built_in (s_intype, BUILT_IN_LLFLOOR);
 543           break;
 544
 545         CASE_FLT_FN (BUILT_IN_ROUND):
 546         CASE_FLT_FN_FLOATN_NX (BUILT_IN_ROUND):
 547           /* Only convert in ISO C99 mode and with -fno-math-errno.  */
 548           if (!targetm.libc_has_function (function_c99_misc, intype)
 549               || flag_errno_math)
 550             break;
 551           if (outprec < TYPE_PRECISION (integer_type_node)
 552               || (outprec == TYPE_PRECISION (integer_type_node)
 553                   && !TYPE_UNSIGNED (type)))
 554             fn = mathfn_built_in (s_intype, BUILT_IN_IROUND);
 555           else if (outprec == TYPE_PRECISION (long_integer_type_node)
 556                    && !TYPE_UNSIGNED (type))
 557             fn = mathfn_built_in (s_intype, BUILT_IN_LROUND);
 558           else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
 559                    && !TYPE_UNSIGNED (type))
 560             fn = mathfn_built_in (s_intype, BUILT_IN_LLROUND);
 561           break;
 562
 563         CASE_FLT_FN (BUILT_IN_NEARBYINT):
 564         CASE_FLT_FN_FLOATN_NX (BUILT_IN_NEARBYINT):
 565           /* Only convert nearbyint* if we can ignore math exceptions.  */
 566           if (flag_trapping_math)
 567             break;
 568           gcc_fallthrough ();
 569         CASE_FLT_FN (BUILT_IN_RINT):
 570         CASE_FLT_FN_FLOATN_NX (BUILT_IN_RINT):
 571           /* Only convert in ISO C99 mode and with -fno-math-errno.  */
 572           if (!targetm.libc_has_function (function_c99_misc, intype)
 573               || flag_errno_math)
 574             break;
 575           if (outprec < TYPE_PRECISION (integer_type_node)
 576               || (outprec == TYPE_PRECISION (integer_type_node)
 577                   && !TYPE_UNSIGNED (type)))
 578             fn = mathfn_built_in (s_intype, BUILT_IN_IRINT);
 579           else if (outprec == TYPE_PRECISION (long_integer_type_node)
 580                    && !TYPE_UNSIGNED (type))
 581             fn = mathfn_built_in (s_intype, BUILT_IN_LRINT);
 582           else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
 583                    && !TYPE_UNSIGNED (type))
 584             fn = mathfn_built_in (s_intype, BUILT_IN_LLRINT);
 585           break;
 586
 587         CASE_FLT_FN (BUILT_IN_TRUNC):
 588         CASE_FLT_FN_FLOATN_NX (BUILT_IN_TRUNC):
 589           if (call_expr_nargs (s_expr) != 1
 590               || !SCALAR_FLOAT_TYPE_P (TREE_TYPE (CALL_EXPR_ARG (s_expr, 0))))
 591             break;
 592           return convert_to_integer_1 (type, CALL_EXPR_ARG (s_expr, 0),
 593                                        dofold);
 594
 595         default:
 596           break;
 597         }
 598
 599       if (fn
 600           && call_expr_nargs (s_expr) == 1
 601           && SCALAR_FLOAT_TYPE_P (TREE_TYPE (CALL_EXPR_ARG (s_expr, 0))))
 602         {
 603           tree newexpr = build_call_expr (fn, 1, CALL_EXPR_ARG (s_expr, 0));
 604           return convert_to_integer_1 (type, newexpr, dofold);
 605         }
 606     }
 607
 608   /* Convert (int)logb(d) -> ilogb(d).  */
 609   if (optimize
 610       && flag_unsafe_math_optimizations
 611       && !flag_trapping_math && !flag_errno_math && flag_finite_math_only
 612       && integer_type_node
 613       && (outprec > TYPE_PRECISION (integer_type_node)
 614           || (outprec == TYPE_PRECISION (integer_type_node)
 615               && !TYPE_UNSIGNED (type))))
 616     {
 617       tree s_expr = strip_float_extensions (expr);
 618       tree s_intype = TREE_TYPE (s_expr);
 619       const enum built_in_function fcode = builtin_mathfn_code (s_expr);
 620       tree fn = 0;
 621
 622       switch (fcode)
 623         {
 624         CASE_FLT_FN (BUILT_IN_LOGB):
 625           fn = mathfn_built_in (s_intype, BUILT_IN_ILOGB);
 626           break;
 627
 628         default:
 629           break;
 630         }
 631
 632       if (fn
 633           && call_expr_nargs (s_expr) == 1
 634           && SCALAR_FLOAT_TYPE_P (TREE_TYPE (CALL_EXPR_ARG (s_expr, 0))))
 635         {
 636           tree newexpr = build_call_expr (fn, 1, CALL_EXPR_ARG (s_expr, 0));
 637           return convert_to_integer_1 (type, newexpr, dofold);
 638         }
 639     }
 640
 641   switch (TREE_CODE (intype))
 642     {
 643     case POINTER_TYPE:
 644     case REFERENCE_TYPE:
 645       if (integer_zerop (expr)
 646           && !TREE_OVERFLOW (tree_strip_any_location_wrapper (expr)))
 647         return build_int_cst (type, 0);
 648
 649       /* Convert to an unsigned integer of the correct width first, and from
 650          there widen/truncate to the required type.  Some targets support the
 651          coexistence of multiple valid pointer sizes, so fetch the one we need
 652          from the type.  */
 653       if (!dofold)
 654         return build1 (CONVERT_EXPR, type, expr);
 655       expr = fold_build1 (CONVERT_EXPR,
 656                           lang_hooks.types.type_for_size
 657                             (TYPE_PRECISION (intype), 0),
 658                           expr);
 659       return fold_convert (type, expr);
 660
 661     case INTEGER_TYPE:
 662     case ENUMERAL_TYPE:
 663     case BOOLEAN_TYPE:
 664     case OFFSET_TYPE:
 665     case BITINT_TYPE:
 666       /* If this is a logical operation, which just returns 0 or 1, we can
 667          change the type of the expression.  */
 668
 669       if (TREE_CODE_CLASS (ex_form) == tcc_comparison)
 670         {
 671           expr = copy_node (expr);
 672           TREE_TYPE (expr) = type;
 673           return expr;
 674         }
 675
 676       /* If we are widening the type, put in an explicit conversion.
 677          Similarly if we are not changing the width.  After this, we know
 678          we are truncating EXPR.  */
 679
 680       else if (outprec >= inprec)
 681         {
 682           enum tree_code code;
 683
 684           /* If the precision of the EXPR's type is K bits and the
 685              destination mode has more bits, and the sign is changing,
 686              it is not safe to use a NOP_EXPR.  For example, suppose
 687              that EXPR's type is a 3-bit unsigned integer type, the
 688              TYPE is a 3-bit signed integer type, and the machine mode
 689              for the types is 8-bit QImode.  In that case, the
 690              conversion necessitates an explicit sign-extension.  In
 691              the signed-to-unsigned case the high-order bits have to
 692              be cleared.  */
 693           if (TYPE_UNSIGNED (type) != TYPE_UNSIGNED (TREE_TYPE (expr))
 694               && !type_has_mode_precision_p (TREE_TYPE (expr)))
 695             code = CONVERT_EXPR;
 696           else
 697             code = NOP_EXPR;
 698
 699           return maybe_fold_build1_loc (dofold, loc, code, type, expr);
 700         }
 701
 702       /* If TYPE is an enumeral type or a type with a precision less
 703          than the number of bits in its mode, do the conversion to the
 704          type corresponding to its mode, then do a nop conversion
 705          to TYPE.  */
 706       else if (TREE_CODE (type) == ENUMERAL_TYPE
 707                || (TREE_CODE (type) != BITINT_TYPE
 708                    && maybe_ne (outprec,
 709                                 GET_MODE_PRECISION (TYPE_MODE (type)))))
 710         {
 711           expr
 712             = convert_to_integer_1 (lang_hooks.types.type_for_mode
 713                                     (TYPE_MODE (type), TYPE_UNSIGNED (type)),
 714                                     expr, dofold);
 715           return maybe_fold_build1_loc (dofold, loc, NOP_EXPR, type, expr);
 716         }
 717
 718       /* Here detect when we can distribute the truncation down past some
 719          arithmetic.  For example, if adding two longs and converting to an
 720          int, we can equally well convert both to ints and then add.
 721          For the operations handled here, such truncation distribution
 722          is always safe.
 723          It is desirable in these cases:
 724          1) when truncating down to full-word from a larger size
 725          2) when truncating takes no work.
 726          3) when at least one operand of the arithmetic has been extended
 727          (as by C's default conversions).  In this case we need two conversions
 728          if we do the arithmetic as already requested, so we might as well
 729          truncate both and then combine.  Perhaps that way we need only one.
 730
 731          Note that in general we cannot do the arithmetic in a type
 732          shorter than the desired result of conversion, even if the operands
 733          are both extended from a shorter type, because they might overflow
 734          if combined in that type.  The exceptions to this--the times when
 735          two narrow values can be combined in their narrow type even to
 736          make a wider result--are handled by "shorten" in build_binary_op.  */
 737
 738       if (dofold)
 739         switch (ex_form)
 740           {
 741           case RSHIFT_EXPR:
 742             /* We can pass truncation down through right shifting
 743                when the shift count is a nonpositive constant.  */
 744             if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST
 745                 && tree_int_cst_sgn (TREE_OPERAND (expr, 1)) <= 0)
 746               goto trunc1;
 747             break;
 748
 749           case LSHIFT_EXPR:
 750             /* We can pass truncation down through left shifting
 751                when the shift count is a nonnegative constant and
 752                the target type is unsigned.  */
 753             if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST
 754                 && tree_int_cst_sgn (TREE_OPERAND (expr, 1)) >= 0
 755                 && TYPE_UNSIGNED (type)
 756                 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
 757               {
 758                 /* If shift count is less than the width of the truncated type,
 759                    really shift.  */
 760                 if (tree_int_cst_lt (TREE_OPERAND (expr, 1), TYPE_SIZE (type)))
 761                   /* In this case, shifting is like multiplication.  */
 762                   goto trunc1;
 763                 else
 764                   {
 765                     /* If it is >= that width, result is zero.
 766                        Handling this with trunc1 would give the wrong result:
 767                        (int) ((long long) a << 32) is well defined (as 0)
 768                        but (int) a << 32 is undefined and would get a
 769                        warning.  */
 770
 771                     tree t = build_int_cst (type, 0);
 772
 773                     /* If the original expression had side-effects, we must
 774                        preserve it.  */
 775                     if (TREE_SIDE_EFFECTS (expr))
 776                       return build2 (COMPOUND_EXPR, type, expr, t);
 777                     else
 778                       return t;
 779                   }
 780               }
 781             break;
 782
 783           case TRUNC_DIV_EXPR:
 784             {
 785               tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), NULL_TREE);
 786               tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), NULL_TREE);
 787
 788               /* Don't distribute unless the output precision is at least as
 789                  big as the actual inputs and it has the same signedness.  */
 790               if (outprec >= TYPE_PRECISION (TREE_TYPE (arg0))
 791                   && outprec >= TYPE_PRECISION (TREE_TYPE (arg1))
 792                   /* If signedness of arg0 and arg1 don't match,
 793                      we can't necessarily find a type to compare them in.  */
 794                   && (TYPE_UNSIGNED (TREE_TYPE (arg0))
 795                       == TYPE_UNSIGNED (TREE_TYPE (arg1)))
 796                   /* Do not change the sign of the division.  */
 797                   && (TYPE_UNSIGNED (TREE_TYPE (expr))
 798                       == TYPE_UNSIGNED (TREE_TYPE (arg0)))
 799                   /* Either require unsigned division or a division by
 800                      a constant that is not -1.  */
 801                   && (TYPE_UNSIGNED (TREE_TYPE (arg0))
 802                       || (TREE_CODE (arg1) == INTEGER_CST
 803                           && !integer_all_onesp (arg1))))
 804                 {
 805                   tree tem = do_narrow (loc, ex_form, type, arg0, arg1,
 806                                         expr, inprec, outprec, dofold);
 807                   if (tem)
 808                     return tem;
 809                 }
 810               break;
 811             }
 812
 813           case MAX_EXPR:
 814           case MIN_EXPR:
 815           case MULT_EXPR:
 816             {
 817               tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type);
 818               tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type);
 819
 820               /* Don't distribute unless the output precision is at least as
 821                  big as the actual inputs.  Otherwise, the comparison of the
 822                  truncated values will be wrong.  */
 823               if (outprec >= TYPE_PRECISION (TREE_TYPE (arg0))
 824                   && outprec >= TYPE_PRECISION (TREE_TYPE (arg1))
 825                   /* If signedness of arg0 and arg1 don't match,
 826                      we can't necessarily find a type to compare them in.  */
 827                   && (TYPE_UNSIGNED (TREE_TYPE (arg0))
 828                       == TYPE_UNSIGNED (TREE_TYPE (arg1))))
 829                 goto trunc1;
 830               break;
 831             }
 832
 833           case PLUS_EXPR:
 834           case MINUS_EXPR:
 835           case BIT_AND_EXPR:
 836           case BIT_IOR_EXPR:
 837           case BIT_XOR_EXPR:
 838           trunc1:
 839             {
 840               tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type);
 841               tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type);
 842
 843               /* Do not try to narrow operands of pointer subtraction;
 844                  that will interfere with other folding.  */
 845               if (ex_form == MINUS_EXPR
 846                   && CONVERT_EXPR_P (arg0)
 847                   && CONVERT_EXPR_P (arg1)
 848                   && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 0)))
 849                   && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (arg1, 0))))
 850                 break;
 851
 852               tree tem = do_narrow (loc, ex_form, type, arg0, arg1,
 853                                     expr, inprec, outprec, dofold);
 854               if (tem)
 855                 return tem;
 856             }
 857             break;
 858
 859           case NEGATE_EXPR:
 860             /* Using unsigned arithmetic for signed types may hide overflow
 861                bugs.  */
 862             if (!TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (expr, 0)))
 863                 && sanitize_flags_p (SANITIZE_SI_OVERFLOW))
 864               break;
 865             /* Fall through.  */
 866           case BIT_NOT_EXPR:
 867             /* This is not correct for ABS_EXPR,
 868                since we must test the sign before truncation.  */
 869             {
 870               /* Do the arithmetic in type TYPEX,
 871                  then convert result to TYPE.  */
 872               tree typex = type;
 873
 874               /* Can't do arithmetic in enumeral types
 875                  so use an integer type that will hold the values.  */
 876               if (TREE_CODE (typex) == ENUMERAL_TYPE)
 877                 typex
 878                   = lang_hooks.types.type_for_size (TYPE_PRECISION (typex),
 879                                                     TYPE_UNSIGNED (typex));
 880
 881               if (!TYPE_UNSIGNED (typex))
 882                 typex = unsigned_type_for (typex);
 883               return convert (type,
 884                               fold_build1 (ex_form, typex,
 885                                            convert (typex,
 886                                                     TREE_OPERAND (expr, 0))));
 887             }
 888
 889           CASE_CONVERT:
 890             {
 891               tree argtype = TREE_TYPE (TREE_OPERAND (expr, 0));
 892               /* Don't introduce a "can't convert between vector values
 893                  of different size" error.  */
 894               if (TREE_CODE (argtype) == VECTOR_TYPE
 895                   && maybe_ne (GET_MODE_SIZE (TYPE_MODE (argtype)),
 896                                GET_MODE_SIZE (TYPE_MODE (type))))
 897                 break;
 898             }
 899             /* If truncating after truncating, might as well do all at once.
 900                If truncating after extending, we may get rid of wasted work.  */
 901             return convert (type, get_unwidened (TREE_OPERAND (expr, 0), type));
 902
 903           case COND_EXPR:
 904             /* It is sometimes worthwhile to push the narrowing down through
 905                the conditional and never loses.  A COND_EXPR may have a throw
 906                as one operand, which then has void type.  Just leave void
 907                operands as they are.  */
 908             return
 909               fold_build3 (COND_EXPR, type, TREE_OPERAND (expr, 0),
 910                            VOID_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 1)))
 911                            ? TREE_OPERAND (expr, 1)
 912                            : convert (type, TREE_OPERAND (expr, 1)),
 913                            VOID_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 2)))
 914                            ? TREE_OPERAND (expr, 2)
 915                            : convert (type, TREE_OPERAND (expr, 2)));
 916
 917           default:
 918             break;
 919           }
 920
 921       /* When parsing long initializers, we might end up with a lot of casts.
 922          Shortcut this.  */
 923       if (TREE_CODE (tree_strip_any_location_wrapper (expr)) == INTEGER_CST)
 924         return fold_convert (type, expr);
 925       return build1 (CONVERT_EXPR, type, expr);
 926
 927     case REAL_TYPE:
 928       if (sanitize_flags_p (SANITIZE_FLOAT_CAST)
 929           && current_function_decl != NULL_TREE)
 930         {
 931           expr = save_expr (expr);
 932           tree check = ubsan_instrument_float_cast (loc, type, expr);
 933           expr = build1 (FIX_TRUNC_EXPR, type, expr);
 934           if (check == NULL_TREE)
 935             return expr;
 936           return maybe_fold_build2_loc (dofold, loc, COMPOUND_EXPR,
 937                                         TREE_TYPE (expr), check, expr);
 938         }
 939       else
 940         return build1 (FIX_TRUNC_EXPR, type, expr);
 941
 942     case FIXED_POINT_TYPE:
 943       return build1 (FIXED_CONVERT_EXPR, type, expr);
 944
 945     case COMPLEX_TYPE:
 946       expr = maybe_fold_build1_loc (dofold, loc, REALPART_EXPR,
 947                                     TREE_TYPE (TREE_TYPE (expr)), expr);
 948       return convert (type, expr);
 949
 950     case VECTOR_TYPE:
 951       if (!tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (TREE_TYPE (expr))))
 952         {
 953           error ("cannot convert a vector of type %qT"
 954                  " to type %qT which has different size",
 955                  TREE_TYPE (expr), type);
 956           return error_mark_node;
 957         }
 958       return build1 (VIEW_CONVERT_EXPR, type, expr);
 959
 960     default:
 961       error ("aggregate value used where an integer was expected");
 962       return error_mark_node;
 963     }
 964 }
 965
 966 /* Convert EXPR to some integer (or enum) type TYPE.
 967
 968    EXPR must be pointer, integer, discrete (enum, char, or bool), float,
 969    fixed-point or vector; in other cases error is called.
 970
 971    The result of this is always supposed to be a newly created tree node
 972    not in use in any existing structure.  */
 973
 974 tree
 975 convert_to_integer (tree type, tree expr)
 976 {
 977   return convert_to_integer_1 (type, expr, true);
 978 }
 979
 980 /* A wrapper around convert_to_complex_1 that only folds the
 981    expression if DOFOLD, or if it is CONSTANT_CLASS_OR_WRAPPER_P.  */
 982
 983 tree
 984 convert_to_integer_maybe_fold (tree type, tree expr, bool dofold)
 985 {
 986   tree result
 987     = convert_to_integer_1 (type, expr,
 988                             dofold || CONSTANT_CLASS_OR_WRAPPER_P (expr));
 989   return preserve_any_location_wrapper (result, expr);
 990 }
 991
 992 /* Convert EXPR to the complex type TYPE in the usual ways.  If FOLD_P is
 993    true, try to fold the expression.  */
 994
 995 static tree
 996 convert_to_complex_1 (tree type, tree expr, bool fold_p)
 997 {
 998   location_t loc = EXPR_LOCATION (expr);
 999   tree subtype = TREE_TYPE (type);
1000
1001   switch (TREE_CODE (TREE_TYPE (expr)))
1002     {
1003     case REAL_TYPE:
1004     case FIXED_POINT_TYPE:
1005     case INTEGER_TYPE:
1006     case ENUMERAL_TYPE:
1007     case BOOLEAN_TYPE:
1008     case BITINT_TYPE:
1009       {
1010         tree real = convert (subtype, expr);
1011         tree imag = convert (subtype, integer_zero_node);
1012         if (error_operand_p (real) || error_operand_p (imag))
1013           return error_mark_node;
1014         return build2 (COMPLEX_EXPR, type, real, imag);
1015       }
1016
1017     case COMPLEX_TYPE:
1018       {
1019         tree elt_type = TREE_TYPE (TREE_TYPE (expr));
1020
1021         if (TYPE_MAIN_VARIANT (elt_type) == TYPE_MAIN_VARIANT (subtype))
1022           return expr;
1023         else if (TREE_CODE (expr) == COMPOUND_EXPR)
1024           {
1025             tree t = convert_to_complex_1 (type, TREE_OPERAND (expr, 1),
1026                                            fold_p);
1027             if (t == TREE_OPERAND (expr, 1))
1028               return expr;
1029             return build2_loc (EXPR_LOCATION (expr), COMPOUND_EXPR,
1030                                TREE_TYPE (t), TREE_OPERAND (expr, 0), t);
1031           }
1032         else if (TREE_CODE (expr) == COMPLEX_EXPR)
1033           return maybe_fold_build2_loc (fold_p, loc, COMPLEX_EXPR, type,
1034                                         convert (subtype,
1035                                                  TREE_OPERAND (expr, 0)),
1036                                         convert (subtype,
1037                                                  TREE_OPERAND (expr, 1)));
1038         else
1039           {
1040             expr = save_expr (expr);
1041             tree realp = maybe_fold_build1_loc (fold_p, loc, REALPART_EXPR,
1042                                                 TREE_TYPE (TREE_TYPE (expr)),
1043                                                 expr);
1044             tree imagp = maybe_fold_build1_loc (fold_p, loc, IMAGPART_EXPR,
1045                                                 TREE_TYPE (TREE_TYPE (expr)),
1046                                                 expr);
1047             return maybe_fold_build2_loc (fold_p, loc, COMPLEX_EXPR, type,
1048                                           convert (subtype, realp),
1049                                           convert (subtype, imagp));
1050           }
1051       }
1052
1053     case POINTER_TYPE:
1054     case REFERENCE_TYPE:
1055       error ("pointer value used where a complex was expected");
1056       return error_mark_node;
1057
1058     default:
1059       error ("aggregate value used where a complex was expected");
1060       return error_mark_node;
1061     }
1062 }
1063
1064 /* A wrapper around convert_to_complex_1 that always folds the
1065    expression.  */
1066
1067 tree
1068 convert_to_complex (tree type, tree expr)
1069 {
1070   return convert_to_complex_1 (type, expr, true);
1071 }
1072
1073 /* A wrapper around convert_to_complex_1 that only folds the
1074    expression if DOFOLD, or if it is CONSTANT_CLASS_OR_WRAPPER_P.  */
1075
1076 tree
1077 convert_to_complex_maybe_fold (tree type, tree expr, bool dofold)
1078 {
1079   tree result
1080     = convert_to_complex_1 (type, expr,
1081                             dofold || CONSTANT_CLASS_OR_WRAPPER_P (expr));
1082   return preserve_any_location_wrapper (result, expr);
1083 }
1084
1085 /* Convert EXPR to the vector type TYPE in the usual ways.  */
1086
1087 tree
1088 convert_to_vector (tree type, tree expr)
1089 {
1090   switch (TREE_CODE (TREE_TYPE (expr)))
1091     {
1092     case INTEGER_TYPE:
1093     case VECTOR_TYPE:
1094       if (!tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (TREE_TYPE (expr))))
1095         {
1096           error ("cannot convert a value of type %qT"
1097                  " to vector type %qT which has different size",
1098                  TREE_TYPE (expr), type);
1099           return error_mark_node;
1100         }
1101       return build1 (VIEW_CONVERT_EXPR, type, expr);
1102
1103     default:
1104       error ("cannot convert value to a vector");
1105       return error_mark_node;
1106     }
1107 }
1108
1109 /* Convert EXPR to some fixed-point type TYPE.
1110
1111    EXPR must be fixed-point, float, integer, or enumeral;
1112    in other cases error is called.  */
1113
1114 tree
1115 convert_to_fixed (tree type, tree expr)
1116 {
1117   if (integer_zerop (expr))
1118     {
1119       tree fixed_zero_node = build_fixed (type, FCONST0 (TYPE_MODE (type)));
1120       return fixed_zero_node;
1121     }
1122   else if (integer_onep (expr) && ALL_SCALAR_ACCUM_MODE_P (TYPE_MODE (type)))
1123     {
1124       tree fixed_one_node = build_fixed (type, FCONST1 (TYPE_MODE (type)));
1125       return fixed_one_node;
1126     }
1127
1128   switch (TREE_CODE (TREE_TYPE (expr)))
1129     {
1130     case FIXED_POINT_TYPE:
1131     case INTEGER_TYPE:
1132     case ENUMERAL_TYPE:
1133     case BOOLEAN_TYPE:
1134     case REAL_TYPE:
1135       return build1 (FIXED_CONVERT_EXPR, type, expr);
1136
1137     case COMPLEX_TYPE:
1138       return convert (type,
1139                       fold_build1 (REALPART_EXPR,
1140                                    TREE_TYPE (TREE_TYPE (expr)), expr));
1141
1142     default:
1143       error ("aggregate value used where a fixed-point was expected");
1144       return error_mark_node;
1145     }
1146 }
1147
1148 #if CHECKING_P
1149
1150 namespace selftest {
1151
1152 /* Selftests for conversions.  */
1153
1154 static void
1155 test_convert_to_integer_maybe_fold (tree orig_type, tree new_type)
1156 {
1157   /* Calling convert_to_integer_maybe_fold on an INTEGER_CST.  */
1158
1159   tree orig_cst = build_int_cst (orig_type, 42);
1160
1161   /* Verify that convert_to_integer_maybe_fold on a constant returns a new
1162      constant of the new type, unless the types are the same, in which
1163      case verify it's a no-op.  */
1164   {
1165     tree result = convert_to_integer_maybe_fold (new_type,
1166                                                  orig_cst, false);
1167     if (orig_type != new_type)
1168       {
1169         ASSERT_EQ (TREE_TYPE (result), new_type);
1170         ASSERT_EQ (TREE_CODE (result), INTEGER_CST);
1171       }
1172     else
1173       ASSERT_EQ (result, orig_cst);
1174   }
1175
1176   /* Calling convert_to_integer_maybe_fold on a location wrapper around
1177      an INTEGER_CST.
1178
1179      Verify that convert_to_integer_maybe_fold on a location wrapper
1180      around a constant returns a new location wrapper around an equivalent
1181      constant, both of the new type, unless the types are the same,
1182      in which case the original wrapper should be returned.   */
1183   {
1184     const location_t loc = BUILTINS_LOCATION;
1185     tree wrapped_orig_cst = maybe_wrap_with_location (orig_cst, loc);
1186     tree result
1187       = convert_to_integer_maybe_fold (new_type, wrapped_orig_cst, false);
1188     ASSERT_EQ (TREE_TYPE (result), new_type);
1189     ASSERT_EQ (EXPR_LOCATION (result), loc);
1190     ASSERT_TRUE (location_wrapper_p (result));
1191     ASSERT_EQ (TREE_TYPE (TREE_OPERAND (result, 0)), new_type);
1192     ASSERT_EQ (TREE_CODE (TREE_OPERAND (result, 0)), INTEGER_CST);
1193
1194     if (orig_type == new_type)
1195       ASSERT_EQ (result, wrapped_orig_cst);
1196   }
1197 }
1198
1199 /* Verify that convert_to_integer_maybe_fold preserves locations.  */
1200
1201 static void
1202 test_convert_to_integer_maybe_fold ()
1203 {
1204   /* char -> long.  */
1205   test_convert_to_integer_maybe_fold (char_type_node, long_integer_type_node);
1206
1207   /* char -> char.  */
1208   test_convert_to_integer_maybe_fold (char_type_node, char_type_node);
1209
1210   /* long -> char.  */
1211   test_convert_to_integer_maybe_fold (char_type_node, long_integer_type_node);
1212
1213   /* long -> long.  */
1214   test_convert_to_integer_maybe_fold (long_integer_type_node,
1215                                       long_integer_type_node);
1216 }
1217
1218 /* Run all of the selftests within this file.  */
1219
1220 void
1221 convert_cc_tests ()
1222 {
1223   test_convert_to_integer_maybe_fold ();
1224 }
1225
1226 } // namespace selftest
1227
1228 #endif /* CHECKING_P */