gcc/convert.cc

   1 /* Utility routines for data type conversion for GCC.
   2    Copyright (C) 1987-2024 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               && element_precision (type) < element_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     case VECTOR_TYPE:
 338       error ("vector value used where a floating-point was expected");
 339       return error_mark_node;
 340
 341     default:
 342       error ("aggregate value used where a floating-point was expected");
 343       return error_mark_node;
 344     }
 345 }
 346
 347 /* A wrapper around convert_to_real_1 that always folds the
 348    expression.  */
 349
 350 tree
 351 convert_to_real (tree type, tree expr)
 352 {
 353   return convert_to_real_1 (type, expr, true);
 354 }
 355
 356 /* A wrapper around convert_to_real_1 that only folds the
 357    expression if DOFOLD, or if it is CONSTANT_CLASS_OR_WRAPPER_P.  */
 358
 359 tree
 360 convert_to_real_maybe_fold (tree type, tree expr, bool dofold)
 361 {
 362   tree result
 363     = convert_to_real_1 (type, expr,
 364                          dofold || CONSTANT_CLASS_OR_WRAPPER_P (expr));
 365   return preserve_any_location_wrapper (result, expr);
 366 }
 367
 368 /* Try to narrow EX_FORM ARG0 ARG1 in narrowed arg types producing a
 369    result in TYPE.  */
 370
 371 static tree
 372 do_narrow (location_t loc,
 373            enum tree_code ex_form, tree type, tree arg0, tree arg1,
 374            tree expr, unsigned inprec, unsigned outprec, bool dofold)
 375 {
 376   /* Do the arithmetic in type TYPEX,
 377      then convert result to TYPE.  */
 378   tree typex = type;
 379
 380   /* Can't do arithmetic in enumeral types
 381      so use an integer type that will hold the values.  */
 382   if (TREE_CODE (typex) == ENUMERAL_TYPE)
 383     typex = lang_hooks.types.type_for_size (TYPE_PRECISION (typex),
 384                                             TYPE_UNSIGNED (typex));
 385
 386   /* The type demotion below might cause doing unsigned arithmetic
 387      instead of signed, and thus hide overflow bugs.  */
 388   if ((ex_form == PLUS_EXPR || ex_form == MINUS_EXPR)
 389       && !TYPE_UNSIGNED (typex)
 390       && sanitize_flags_p (SANITIZE_SI_OVERFLOW))
 391     return NULL_TREE;
 392
 393   /* Similarly for multiplication, but in that case it can be
 394      problematic even if typex is unsigned type - 0xffff * 0xffff
 395      overflows in int.  */
 396   if (ex_form == MULT_EXPR
 397       && !TYPE_OVERFLOW_WRAPS (TREE_TYPE (expr))
 398       && sanitize_flags_p (SANITIZE_SI_OVERFLOW))
 399     return NULL_TREE;
 400
 401   /* But now perhaps TYPEX is as wide as INPREC.
 402      In that case, do nothing special here.
 403      (Otherwise would recurse infinitely in convert.  */
 404   if (TYPE_PRECISION (typex) != inprec)
 405     {
 406       /* Don't do unsigned arithmetic where signed was wanted,
 407          or vice versa.
 408          Exception: if both of the original operands were
 409          unsigned then we can safely do the work as unsigned.
 410          Exception: shift operations take their type solely
 411          from the first argument.
 412          Exception: the LSHIFT_EXPR case above requires that
 413          we perform this operation unsigned lest we produce
 414          signed-overflow undefinedness.
 415          And we may need to do it as unsigned
 416          if we truncate to the original size.  */
 417       if (TYPE_UNSIGNED (TREE_TYPE (expr))
 418           || (TYPE_UNSIGNED (TREE_TYPE (arg0))
 419               && (TYPE_UNSIGNED (TREE_TYPE (arg1))
 420                   || ex_form == LSHIFT_EXPR
 421                   || ex_form == RSHIFT_EXPR
 422                   || ex_form == LROTATE_EXPR
 423                   || ex_form == RROTATE_EXPR))
 424           || ex_form == LSHIFT_EXPR
 425           /* If we have !flag_wrapv, and either ARG0 or
 426              ARG1 is of a signed type, we have to do
 427              PLUS_EXPR, MINUS_EXPR or MULT_EXPR in an unsigned
 428              type in case the operation in outprec precision
 429              could overflow.  Otherwise, we would introduce
 430              signed-overflow undefinedness.  */
 431           || ((!(INTEGRAL_TYPE_P (TREE_TYPE (arg0))
 432                  && TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0)))
 433                || !(INTEGRAL_TYPE_P (TREE_TYPE (arg1))
 434                     && TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg1))))
 435               && ((TYPE_PRECISION (TREE_TYPE (arg0)) * 2u
 436                    > outprec)
 437                   || (TYPE_PRECISION (TREE_TYPE (arg1)) * 2u
 438                       > outprec))
 439               && (ex_form == PLUS_EXPR
 440                   || ex_form == MINUS_EXPR
 441                   || ex_form == MULT_EXPR)))
 442         {
 443           if (!TYPE_UNSIGNED (typex))
 444             typex = unsigned_type_for (typex);
 445         }
 446       else
 447         {
 448           if (TYPE_UNSIGNED (typex))
 449             typex = signed_type_for (typex);
 450         }
 451       /* We should do away with all this once we have a proper
 452          type promotion/demotion pass, see PR45397.  */
 453       expr = maybe_fold_build2_loc (dofold, loc, ex_form, typex,
 454                                     convert (typex, arg0),
 455                                     convert (typex, arg1));
 456       return convert (type, expr);
 457     }
 458
 459   return NULL_TREE;
 460 }
 461
 462 /* Convert EXPR to some integer (or enum) type TYPE.
 463
 464    EXPR must be pointer, integer, discrete (enum, char, or bool), float,
 465    fixed-point or vector; in other cases error is called.
 466
 467    If DOFOLD is TRUE, we try to simplify newly-created patterns by folding.
 468
 469    The result of this is always supposed to be a newly created tree node
 470    not in use in any existing structure.  */
 471
 472 static tree
 473 convert_to_integer_1 (tree type, tree expr, bool dofold)
 474 {
 475   enum tree_code ex_form = TREE_CODE (expr);
 476   tree intype = TREE_TYPE (expr);
 477   unsigned int inprec = element_precision (intype);
 478   unsigned int outprec = element_precision (type);
 479   location_t loc = EXPR_LOCATION (expr);
 480
 481   /* An INTEGER_TYPE cannot be incomplete, but an ENUMERAL_TYPE can
 482      be.  Consider `enum E = { a, b = (enum E) 3 };'.  */
 483   if (!COMPLETE_TYPE_P (type))
 484     {
 485       error ("conversion to incomplete type");
 486       return error_mark_node;
 487     }
 488
 489   if (ex_form == COMPOUND_EXPR)
 490     {
 491       tree t = convert_to_integer_1 (type, TREE_OPERAND (expr, 1), dofold);
 492       if (t == TREE_OPERAND (expr, 1))
 493         return expr;
 494       return build2_loc (EXPR_LOCATION (expr), COMPOUND_EXPR, TREE_TYPE (t),
 495                          TREE_OPERAND (expr, 0), t);
 496     }
 497
 498   /* Convert e.g. (long)round(d) -> lround(d).  */
 499   /* If we're converting to char, we may encounter differing behavior
 500      between converting from double->char vs double->long->char.
 501      We're in "undefined" territory but we prefer to be conservative,
 502      so only proceed in "unsafe" math mode.  */
 503   if (optimize
 504       && (flag_unsafe_math_optimizations
 505           || (long_integer_type_node
 506               && outprec >= TYPE_PRECISION (long_integer_type_node))))
 507     {
 508       tree s_expr = strip_float_extensions (expr);
 509       tree s_intype = TREE_TYPE (s_expr);
 510       const enum built_in_function fcode = builtin_mathfn_code (s_expr);
 511       tree fn = 0;
 512
 513       switch (fcode)
 514         {
 515         CASE_FLT_FN (BUILT_IN_CEIL):
 516         CASE_FLT_FN_FLOATN_NX (BUILT_IN_CEIL):
 517           /* Only convert in ISO C99 mode.  */
 518           if (!targetm.libc_has_function (function_c99_misc, intype))
 519             break;
 520           if (outprec < TYPE_PRECISION (integer_type_node)
 521               || (outprec == TYPE_PRECISION (integer_type_node)
 522                   && !TYPE_UNSIGNED (type)))
 523             fn = mathfn_built_in (s_intype, BUILT_IN_ICEIL);
 524           else if (outprec == TYPE_PRECISION (long_integer_type_node)
 525                    && !TYPE_UNSIGNED (type))
 526             fn = mathfn_built_in (s_intype, BUILT_IN_LCEIL);
 527           else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
 528                    && !TYPE_UNSIGNED (type))
 529             fn = mathfn_built_in (s_intype, BUILT_IN_LLCEIL);
 530           break;
 531
 532         CASE_FLT_FN (BUILT_IN_FLOOR):
 533         CASE_FLT_FN_FLOATN_NX (BUILT_IN_FLOOR):
 534           /* Only convert in ISO C99 mode.  */
 535           if (!targetm.libc_has_function (function_c99_misc, intype))
 536             break;
 537           if (outprec < TYPE_PRECISION (integer_type_node)
 538               || (outprec == TYPE_PRECISION (integer_type_node)
 539                   && !TYPE_UNSIGNED (type)))
 540             fn = mathfn_built_in (s_intype, BUILT_IN_IFLOOR);
 541           else if (outprec == TYPE_PRECISION (long_integer_type_node)
 542                    && !TYPE_UNSIGNED (type))
 543             fn = mathfn_built_in (s_intype, BUILT_IN_LFLOOR);
 544           else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
 545                    && !TYPE_UNSIGNED (type))
 546             fn = mathfn_built_in (s_intype, BUILT_IN_LLFLOOR);
 547           break;
 548
 549         CASE_FLT_FN (BUILT_IN_ROUND):
 550         CASE_FLT_FN_FLOATN_NX (BUILT_IN_ROUND):
 551           /* Only convert in ISO C99 mode and with -fno-math-errno.  */
 552           if (!targetm.libc_has_function (function_c99_misc, intype)
 553               || flag_errno_math)
 554             break;
 555           if (outprec < TYPE_PRECISION (integer_type_node)
 556               || (outprec == TYPE_PRECISION (integer_type_node)
 557                   && !TYPE_UNSIGNED (type)))
 558             fn = mathfn_built_in (s_intype, BUILT_IN_IROUND);
 559           else if (outprec == TYPE_PRECISION (long_integer_type_node)
 560                    && !TYPE_UNSIGNED (type))
 561             fn = mathfn_built_in (s_intype, BUILT_IN_LROUND);
 562           else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
 563                    && !TYPE_UNSIGNED (type))
 564             fn = mathfn_built_in (s_intype, BUILT_IN_LLROUND);
 565           break;
 566
 567         CASE_FLT_FN (BUILT_IN_NEARBYINT):
 568         CASE_FLT_FN_FLOATN_NX (BUILT_IN_NEARBYINT):
 569           /* Only convert nearbyint* if we can ignore math exceptions.  */
 570           if (flag_trapping_math)
 571             break;
 572           gcc_fallthrough ();
 573         CASE_FLT_FN (BUILT_IN_RINT):
 574         CASE_FLT_FN_FLOATN_NX (BUILT_IN_RINT):
 575           /* Only convert in ISO C99 mode and with -fno-math-errno.  */
 576           if (!targetm.libc_has_function (function_c99_misc, intype)
 577               || flag_errno_math)
 578             break;
 579           if (outprec < TYPE_PRECISION (integer_type_node)
 580               || (outprec == TYPE_PRECISION (integer_type_node)
 581                   && !TYPE_UNSIGNED (type)))
 582             fn = mathfn_built_in (s_intype, BUILT_IN_IRINT);
 583           else if (outprec == TYPE_PRECISION (long_integer_type_node)
 584                    && !TYPE_UNSIGNED (type))
 585             fn = mathfn_built_in (s_intype, BUILT_IN_LRINT);
 586           else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
 587                    && !TYPE_UNSIGNED (type))
 588             fn = mathfn_built_in (s_intype, BUILT_IN_LLRINT);
 589           break;
 590
 591         CASE_FLT_FN (BUILT_IN_TRUNC):
 592         CASE_FLT_FN_FLOATN_NX (BUILT_IN_TRUNC):
 593           if (call_expr_nargs (s_expr) != 1
 594               || !SCALAR_FLOAT_TYPE_P (TREE_TYPE (CALL_EXPR_ARG (s_expr, 0)))
 595               || (!flag_fp_int_builtin_inexact && flag_trapping_math))
 596             break;
 597           return convert_to_integer_1 (type, CALL_EXPR_ARG (s_expr, 0),
 598                                        dofold);
 599
 600         default:
 601           break;
 602         }
 603
 604       if (fn
 605           && call_expr_nargs (s_expr) == 1
 606           && SCALAR_FLOAT_TYPE_P (TREE_TYPE (CALL_EXPR_ARG (s_expr, 0))))
 607         {
 608           tree newexpr = build_call_expr (fn, 1, CALL_EXPR_ARG (s_expr, 0));
 609           return convert_to_integer_1 (type, newexpr, dofold);
 610         }
 611     }
 612
 613   /* Convert (int)logb(d) -> ilogb(d).  */
 614   if (optimize
 615       && flag_unsafe_math_optimizations
 616       && !flag_trapping_math && !flag_errno_math && flag_finite_math_only
 617       && integer_type_node
 618       && (outprec > TYPE_PRECISION (integer_type_node)
 619           || (outprec == TYPE_PRECISION (integer_type_node)
 620               && !TYPE_UNSIGNED (type))))
 621     {
 622       tree s_expr = strip_float_extensions (expr);
 623       tree s_intype = TREE_TYPE (s_expr);
 624       const enum built_in_function fcode = builtin_mathfn_code (s_expr);
 625       tree fn = 0;
 626
 627       switch (fcode)
 628         {
 629         CASE_FLT_FN (BUILT_IN_LOGB):
 630           fn = mathfn_built_in (s_intype, BUILT_IN_ILOGB);
 631           break;
 632
 633         default:
 634           break;
 635         }
 636
 637       if (fn
 638           && call_expr_nargs (s_expr) == 1
 639           && SCALAR_FLOAT_TYPE_P (TREE_TYPE (CALL_EXPR_ARG (s_expr, 0))))
 640         {
 641           tree newexpr = build_call_expr (fn, 1, CALL_EXPR_ARG (s_expr, 0));
 642           return convert_to_integer_1 (type, newexpr, dofold);
 643         }
 644     }
 645
 646   switch (TREE_CODE (intype))
 647     {
 648     case POINTER_TYPE:
 649     case REFERENCE_TYPE:
 650       if (integer_zerop (expr)
 651           && !TREE_OVERFLOW (tree_strip_any_location_wrapper (expr)))
 652         return build_int_cst (type, 0);
 653
 654       /* Convert to an unsigned integer of the correct width first, and from
 655          there widen/truncate to the required type.  Some targets support the
 656          coexistence of multiple valid pointer sizes, so fetch the one we need
 657          from the type.  */
 658       if (!dofold)
 659         return build1 (CONVERT_EXPR, type, expr);
 660       expr = fold_build1 (CONVERT_EXPR,
 661                           lang_hooks.types.type_for_size
 662                             (TYPE_PRECISION (intype), 0),
 663                           expr);
 664       return fold_convert (type, expr);
 665
 666     case INTEGER_TYPE:
 667     case ENUMERAL_TYPE:
 668     case BOOLEAN_TYPE:
 669     case OFFSET_TYPE:
 670     case BITINT_TYPE:
 671       /* If this is a logical operation, which just returns 0 or 1, we can
 672          change the type of the expression.  */
 673
 674       if (TREE_CODE_CLASS (ex_form) == tcc_comparison)
 675         {
 676           expr = copy_node (expr);
 677           TREE_TYPE (expr) = type;
 678           return expr;
 679         }
 680
 681       /* If we are widening the type, put in an explicit conversion.
 682          Similarly if we are not changing the width.  After this, we know
 683          we are truncating EXPR.  */
 684
 685       else if (outprec >= inprec)
 686         {
 687           enum tree_code code;
 688
 689           /* If the precision of the EXPR's type is K bits and the
 690              destination mode has more bits, and the sign is changing,
 691              it is not safe to use a NOP_EXPR.  For example, suppose
 692              that EXPR's type is a 3-bit unsigned integer type, the
 693              TYPE is a 3-bit signed integer type, and the machine mode
 694              for the types is 8-bit QImode.  In that case, the
 695              conversion necessitates an explicit sign-extension.  In
 696              the signed-to-unsigned case the high-order bits have to
 697              be cleared.  */
 698           if (TYPE_UNSIGNED (type) != TYPE_UNSIGNED (TREE_TYPE (expr))
 699               && !type_has_mode_precision_p (TREE_TYPE (expr)))
 700             code = CONVERT_EXPR;
 701           else
 702             code = NOP_EXPR;
 703
 704           return maybe_fold_build1_loc (dofold, loc, code, type, expr);
 705         }
 706
 707       /* If TYPE is an enumeral type or a type with a precision less
 708          than the number of bits in its mode, do the conversion to the
 709          type corresponding to its mode, then do a nop conversion
 710          to TYPE.  */
 711       else if (TREE_CODE (type) == ENUMERAL_TYPE
 712                || (TREE_CODE (type) != BITINT_TYPE
 713                    && maybe_ne (outprec,
 714                                 GET_MODE_PRECISION (TYPE_MODE (type)))))
 715         {
 716           expr
 717             = convert_to_integer_1 (lang_hooks.types.type_for_mode
 718                                     (TYPE_MODE (type), TYPE_UNSIGNED (type)),
 719                                     expr, dofold);
 720           return maybe_fold_build1_loc (dofold, loc, NOP_EXPR, type, expr);
 721         }
 722
 723       /* Here detect when we can distribute the truncation down past some
 724          arithmetic.  For example, if adding two longs and converting to an
 725          int, we can equally well convert both to ints and then add.
 726          For the operations handled here, such truncation distribution
 727          is always safe.
 728          It is desirable in these cases:
 729          1) when truncating down to full-word from a larger size
 730          2) when truncating takes no work.
 731          3) when at least one operand of the arithmetic has been extended
 732          (as by C's default conversions).  In this case we need two conversions
 733          if we do the arithmetic as already requested, so we might as well
 734          truncate both and then combine.  Perhaps that way we need only one.
 735
 736          Note that in general we cannot do the arithmetic in a type
 737          shorter than the desired result of conversion, even if the operands
 738          are both extended from a shorter type, because they might overflow
 739          if combined in that type.  The exceptions to this--the times when
 740          two narrow values can be combined in their narrow type even to
 741          make a wider result--are handled by "shorten" in build_binary_op.  */
 742
 743       if (dofold)
 744         switch (ex_form)
 745           {
 746           case RSHIFT_EXPR:
 747             /* We can pass truncation down through right shifting
 748                when the shift count is a nonpositive constant.  */
 749             if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST
 750                 && tree_int_cst_sgn (TREE_OPERAND (expr, 1)) <= 0)
 751               goto trunc1;
 752             break;
 753
 754           case LSHIFT_EXPR:
 755             /* We can pass truncation down through left shifting
 756                when the shift count is a nonnegative constant and
 757                the target type is unsigned.  */
 758             if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST
 759                 && tree_int_cst_sgn (TREE_OPERAND (expr, 1)) >= 0
 760                 && TYPE_UNSIGNED (type)
 761                 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
 762               {
 763                 /* If shift count is less than the width of the truncated type,
 764                    really shift.  */
 765                 if (tree_int_cst_lt (TREE_OPERAND (expr, 1), TYPE_SIZE (type)))
 766                   /* In this case, shifting is like multiplication.  */
 767                   goto trunc1;
 768                 else
 769                   {
 770                     /* If it is >= that width, result is zero.
 771                        Handling this with trunc1 would give the wrong result:
 772                        (int) ((long long) a << 32) is well defined (as 0)
 773                        but (int) a << 32 is undefined and would get a
 774                        warning.  */
 775
 776                     tree t = build_int_cst (type, 0);
 777
 778                     /* If the original expression had side-effects, we must
 779                        preserve it.  */
 780                     if (TREE_SIDE_EFFECTS (expr))
 781                       return build2 (COMPOUND_EXPR, type, expr, t);
 782                     else
 783                       return t;
 784                   }
 785               }
 786             break;
 787
 788           case TRUNC_DIV_EXPR:
 789             {
 790               tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), NULL_TREE);
 791               tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), NULL_TREE);
 792
 793               /* Don't distribute unless the output precision is at least as
 794                  big as the actual inputs and it has the same signedness.  */
 795               if (outprec >= TYPE_PRECISION (TREE_TYPE (arg0))
 796                   && outprec >= TYPE_PRECISION (TREE_TYPE (arg1))
 797                   /* If signedness of arg0 and arg1 don't match,
 798                      we can't necessarily find a type to compare them in.  */
 799                   && (TYPE_UNSIGNED (TREE_TYPE (arg0))
 800                       == TYPE_UNSIGNED (TREE_TYPE (arg1)))
 801                   /* Do not change the sign of the division.  */
 802                   && (TYPE_UNSIGNED (TREE_TYPE (expr))
 803                       == TYPE_UNSIGNED (TREE_TYPE (arg0)))
 804                   /* Either require unsigned division or a division by
 805                      a constant that is not -1.  */
 806                   && (TYPE_UNSIGNED (TREE_TYPE (arg0))
 807                       || (TREE_CODE (arg1) == INTEGER_CST
 808                           && !integer_all_onesp (arg1))))
 809                 {
 810                   tree tem = do_narrow (loc, ex_form, type, arg0, arg1,
 811                                         expr, inprec, outprec, dofold);
 812                   if (tem)
 813                     return tem;
 814                 }
 815               break;
 816             }
 817
 818           case MAX_EXPR:
 819           case MIN_EXPR:
 820           case MULT_EXPR:
 821             {
 822               tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type);
 823               tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type);
 824
 825               /* Don't distribute unless the output precision is at least as
 826                  big as the actual inputs.  Otherwise, the comparison of the
 827                  truncated values will be wrong.  */
 828               if (outprec >= TYPE_PRECISION (TREE_TYPE (arg0))
 829                   && outprec >= TYPE_PRECISION (TREE_TYPE (arg1))
 830                   /* If signedness of arg0 and arg1 don't match,
 831                      we can't necessarily find a type to compare them in.  */
 832                   && (TYPE_UNSIGNED (TREE_TYPE (arg0))
 833                       == TYPE_UNSIGNED (TREE_TYPE (arg1))))
 834                 goto trunc1;
 835               break;
 836             }
 837
 838           case PLUS_EXPR:
 839           case MINUS_EXPR:
 840           case BIT_AND_EXPR:
 841           case BIT_IOR_EXPR:
 842           case BIT_XOR_EXPR:
 843           trunc1:
 844             {
 845               tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type);
 846               tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type);
 847
 848               /* Do not try to narrow operands of pointer subtraction;
 849                  that will interfere with other folding.  */
 850               if (ex_form == MINUS_EXPR
 851                   && CONVERT_EXPR_P (arg0)
 852                   && CONVERT_EXPR_P (arg1)
 853                   && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 0)))
 854                   && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (arg1, 0))))
 855                 break;
 856
 857               tree tem = do_narrow (loc, ex_form, type, arg0, arg1,
 858                                     expr, inprec, outprec, dofold);
 859               if (tem)
 860                 return tem;
 861             }
 862             break;
 863
 864           case NEGATE_EXPR:
 865             /* Using unsigned arithmetic for signed types may hide overflow
 866                bugs.  */
 867             if (!TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (expr, 0)))
 868                 && sanitize_flags_p (SANITIZE_SI_OVERFLOW))
 869               break;
 870             /* Fall through.  */
 871           case BIT_NOT_EXPR:
 872             /* This is not correct for ABS_EXPR,
 873                since we must test the sign before truncation.  */
 874             {
 875               /* Do the arithmetic in type TYPEX,
 876                  then convert result to TYPE.  */
 877               tree typex = type;
 878
 879               /* Can't do arithmetic in enumeral types
 880                  so use an integer type that will hold the values.  */
 881               if (TREE_CODE (typex) == ENUMERAL_TYPE)
 882                 typex
 883                   = lang_hooks.types.type_for_size (TYPE_PRECISION (typex),
 884                                                     TYPE_UNSIGNED (typex));
 885
 886               if (!TYPE_UNSIGNED (typex))
 887                 typex = unsigned_type_for (typex);
 888               return convert (type,
 889                               fold_build1 (ex_form, typex,
 890                                            convert (typex,
 891                                                     TREE_OPERAND (expr, 0))));
 892             }
 893
 894           CASE_CONVERT:
 895             {
 896               tree argtype = TREE_TYPE (TREE_OPERAND (expr, 0));
 897               /* Don't introduce a "can't convert between vector values
 898                  of different size" error.  */
 899               if (TREE_CODE (argtype) == VECTOR_TYPE
 900                   && maybe_ne (GET_MODE_SIZE (TYPE_MODE (argtype)),
 901                                GET_MODE_SIZE (TYPE_MODE (type))))
 902                 break;
 903             }
 904             /* If truncating after truncating, might as well do all at once.
 905                If truncating after extending, we may get rid of wasted work.  */
 906             return convert (type, get_unwidened (TREE_OPERAND (expr, 0), type));
 907
 908           case COND_EXPR:
 909             /* It is sometimes worthwhile to push the narrowing down through
 910                the conditional and never loses.  A COND_EXPR may have a throw
 911                as one operand, which then has void type.  Just leave void
 912                operands as they are.  */
 913             return
 914               fold_build3 (COND_EXPR, type, TREE_OPERAND (expr, 0),
 915                            VOID_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 1)))
 916                            ? TREE_OPERAND (expr, 1)
 917                            : convert (type, TREE_OPERAND (expr, 1)),
 918                            VOID_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 2)))
 919                            ? TREE_OPERAND (expr, 2)
 920                            : convert (type, TREE_OPERAND (expr, 2)));
 921
 922           default:
 923             break;
 924           }
 925
 926       /* When parsing long initializers, we might end up with a lot of casts.
 927          Shortcut this.  */
 928       if (TREE_CODE (tree_strip_any_location_wrapper (expr)) == INTEGER_CST)
 929         return fold_convert (type, expr);
 930       return build1 (CONVERT_EXPR, type, expr);
 931
 932     case REAL_TYPE:
 933       if (sanitize_flags_p (SANITIZE_FLOAT_CAST)
 934           && current_function_decl != NULL_TREE)
 935         {
 936           expr = save_expr (expr);
 937           tree check = ubsan_instrument_float_cast (loc, type, expr);
 938           expr = build1 (FIX_TRUNC_EXPR, type, expr);
 939           if (check == NULL_TREE)
 940             return expr;
 941           return maybe_fold_build2_loc (dofold, loc, COMPOUND_EXPR,
 942                                         TREE_TYPE (expr), check, expr);
 943         }
 944       else
 945         return build1 (FIX_TRUNC_EXPR, type, expr);
 946
 947     case FIXED_POINT_TYPE:
 948       return build1 (FIXED_CONVERT_EXPR, type, expr);
 949
 950     case COMPLEX_TYPE:
 951       expr = maybe_fold_build1_loc (dofold, loc, REALPART_EXPR,
 952                                     TREE_TYPE (TREE_TYPE (expr)), expr);
 953       return convert (type, expr);
 954
 955     case VECTOR_TYPE:
 956       if (!tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (TREE_TYPE (expr))))
 957         {
 958           error ("cannot convert a vector of type %qT"
 959                  " to type %qT which has different size",
 960                  TREE_TYPE (expr), type);
 961           return error_mark_node;
 962         }
 963       return build1 (VIEW_CONVERT_EXPR, type, expr);
 964
 965     default:
 966       error ("aggregate value used where an integer was expected");
 967       return error_mark_node;
 968     }
 969 }
 970
 971 /* Convert EXPR to some integer (or enum) type TYPE.
 972
 973    EXPR must be pointer, integer, discrete (enum, char, or bool), float,
 974    fixed-point or vector; in other cases error is called.
 975
 976    The result of this is always supposed to be a newly created tree node
 977    not in use in any existing structure.  */
 978
 979 tree
 980 convert_to_integer (tree type, tree expr)
 981 {
 982   return convert_to_integer_1 (type, expr, true);
 983 }
 984
 985 /* A wrapper around convert_to_complex_1 that only folds the
 986    expression if DOFOLD, or if it is CONSTANT_CLASS_OR_WRAPPER_P.  */
 987
 988 tree
 989 convert_to_integer_maybe_fold (tree type, tree expr, bool dofold)
 990 {
 991   tree result
 992     = convert_to_integer_1 (type, expr,
 993                             dofold || CONSTANT_CLASS_OR_WRAPPER_P (expr));
 994   return preserve_any_location_wrapper (result, expr);
 995 }
 996
 997 /* Convert EXPR to the complex type TYPE in the usual ways.  If FOLD_P is
 998    true, try to fold the expression.  */
 999
1000 static tree
1001 convert_to_complex_1 (tree type, tree expr, bool fold_p)
1002 {
1003   location_t loc = EXPR_LOCATION (expr);
1004   tree subtype = TREE_TYPE (type);
1005
1006   switch (TREE_CODE (TREE_TYPE (expr)))
1007     {
1008     case REAL_TYPE:
1009     case FIXED_POINT_TYPE:
1010     case INTEGER_TYPE:
1011     case ENUMERAL_TYPE:
1012     case BOOLEAN_TYPE:
1013     case BITINT_TYPE:
1014       {
1015         tree real = convert (subtype, expr);
1016         tree imag = convert (subtype, integer_zero_node);
1017         if (error_operand_p (real) || error_operand_p (imag))
1018           return error_mark_node;
1019         return build2 (COMPLEX_EXPR, type, real, imag);
1020       }
1021
1022     case COMPLEX_TYPE:
1023       {
1024         tree elt_type = TREE_TYPE (TREE_TYPE (expr));
1025
1026         if (TYPE_MAIN_VARIANT (elt_type) == TYPE_MAIN_VARIANT (subtype))
1027           return expr;
1028         else if (TREE_CODE (expr) == COMPOUND_EXPR)
1029           {
1030             tree t = convert_to_complex_1 (type, TREE_OPERAND (expr, 1),
1031                                            fold_p);
1032             if (t == TREE_OPERAND (expr, 1))
1033               return expr;
1034             return build2_loc (EXPR_LOCATION (expr), COMPOUND_EXPR,
1035                                TREE_TYPE (t), TREE_OPERAND (expr, 0), t);
1036           }
1037         else if (TREE_CODE (expr) == COMPLEX_EXPR)
1038           return maybe_fold_build2_loc (fold_p, loc, COMPLEX_EXPR, type,
1039                                         convert (subtype,
1040                                                  TREE_OPERAND (expr, 0)),
1041                                         convert (subtype,
1042                                                  TREE_OPERAND (expr, 1)));
1043         else
1044           {
1045             expr = save_expr (expr);
1046             tree realp = maybe_fold_build1_loc (fold_p, loc, REALPART_EXPR,
1047                                                 TREE_TYPE (TREE_TYPE (expr)),
1048                                                 expr);
1049             tree imagp = maybe_fold_build1_loc (fold_p, loc, IMAGPART_EXPR,
1050                                                 TREE_TYPE (TREE_TYPE (expr)),
1051                                                 expr);
1052             return maybe_fold_build2_loc (fold_p, loc, COMPLEX_EXPR, type,
1053                                           convert (subtype, realp),
1054                                           convert (subtype, imagp));
1055           }
1056       }
1057
1058     case POINTER_TYPE:
1059     case REFERENCE_TYPE:
1060       error ("pointer value used where a complex was expected");
1061       return error_mark_node;
1062
1063     default:
1064       error ("aggregate value used where a complex was expected");
1065       return error_mark_node;
1066     }
1067 }
1068
1069 /* A wrapper around convert_to_complex_1 that always folds the
1070    expression.  */
1071
1072 tree
1073 convert_to_complex (tree type, tree expr)
1074 {
1075   return convert_to_complex_1 (type, expr, true);
1076 }
1077
1078 /* A wrapper around convert_to_complex_1 that only folds the
1079    expression if DOFOLD, or if it is CONSTANT_CLASS_OR_WRAPPER_P.  */
1080
1081 tree
1082 convert_to_complex_maybe_fold (tree type, tree expr, bool dofold)
1083 {
1084   tree result
1085     = convert_to_complex_1 (type, expr,
1086                             dofold || CONSTANT_CLASS_OR_WRAPPER_P (expr));
1087   return preserve_any_location_wrapper (result, expr);
1088 }
1089
1090 /* Convert EXPR to the vector type TYPE in the usual ways.  */
1091
1092 tree
1093 convert_to_vector (tree type, tree expr)
1094 {
1095   switch (TREE_CODE (TREE_TYPE (expr)))
1096     {
1097     case INTEGER_TYPE:
1098     case VECTOR_TYPE:
1099       if (!tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (TREE_TYPE (expr))))
1100         {
1101           error ("cannot convert a value of type %qT"
1102                  " to vector type %qT which has different size",
1103                  TREE_TYPE (expr), type);
1104           return error_mark_node;
1105         }
1106       return build1 (VIEW_CONVERT_EXPR, type, expr);
1107
1108     default:
1109       error ("cannot convert value to a vector");
1110       return error_mark_node;
1111     }
1112 }
1113
1114 /* Convert EXPR to some fixed-point type TYPE.
1115
1116    EXPR must be fixed-point, float, integer, or enumeral;
1117    in other cases error is called.  */
1118
1119 tree
1120 convert_to_fixed (tree type, tree expr)
1121 {
1122   if (integer_zerop (expr))
1123     {
1124       tree fixed_zero_node = build_fixed (type, FCONST0 (TYPE_MODE (type)));
1125       return fixed_zero_node;
1126     }
1127   else if (integer_onep (expr) && ALL_SCALAR_ACCUM_MODE_P (TYPE_MODE (type)))
1128     {
1129       tree fixed_one_node = build_fixed (type, FCONST1 (TYPE_MODE (type)));
1130       return fixed_one_node;
1131     }
1132
1133   switch (TREE_CODE (TREE_TYPE (expr)))
1134     {
1135     case FIXED_POINT_TYPE:
1136     case INTEGER_TYPE:
1137     case ENUMERAL_TYPE:
1138     case BOOLEAN_TYPE:
1139     case REAL_TYPE:
1140       return build1 (FIXED_CONVERT_EXPR, type, expr);
1141
1142     case COMPLEX_TYPE:
1143       return convert (type,
1144                       fold_build1 (REALPART_EXPR,
1145                                    TREE_TYPE (TREE_TYPE (expr)), expr));
1146
1147     default:
1148       error ("aggregate value used where a fixed-point was expected");
1149       return error_mark_node;
1150     }
1151 }
1152
1153 #if CHECKING_P
1154
1155 namespace selftest {
1156
1157 /* Selftests for conversions.  */
1158
1159 static void
1160 test_convert_to_integer_maybe_fold (tree orig_type, tree new_type)
1161 {
1162   /* Calling convert_to_integer_maybe_fold on an INTEGER_CST.  */
1163
1164   tree orig_cst = build_int_cst (orig_type, 42);
1165
1166   /* Verify that convert_to_integer_maybe_fold on a constant returns a new
1167      constant of the new type, unless the types are the same, in which
1168      case verify it's a no-op.  */
1169   {
1170     tree result = convert_to_integer_maybe_fold (new_type,
1171                                                  orig_cst, false);
1172     if (orig_type != new_type)
1173       {
1174         ASSERT_EQ (TREE_TYPE (result), new_type);
1175         ASSERT_EQ (TREE_CODE (result), INTEGER_CST);
1176       }
1177     else
1178       ASSERT_EQ (result, orig_cst);
1179   }
1180
1181   /* Calling convert_to_integer_maybe_fold on a location wrapper around
1182      an INTEGER_CST.
1183
1184      Verify that convert_to_integer_maybe_fold on a location wrapper
1185      around a constant returns a new location wrapper around an equivalent
1186      constant, both of the new type, unless the types are the same,
1187      in which case the original wrapper should be returned.   */
1188   {
1189     const location_t loc = BUILTINS_LOCATION;
1190     tree wrapped_orig_cst = maybe_wrap_with_location (orig_cst, loc);
1191     tree result
1192       = convert_to_integer_maybe_fold (new_type, wrapped_orig_cst, false);
1193     ASSERT_EQ (TREE_TYPE (result), new_type);
1194     ASSERT_EQ (EXPR_LOCATION (result), loc);
1195     ASSERT_TRUE (location_wrapper_p (result));
1196     ASSERT_EQ (TREE_TYPE (TREE_OPERAND (result, 0)), new_type);
1197     ASSERT_EQ (TREE_CODE (TREE_OPERAND (result, 0)), INTEGER_CST);
1198
1199     if (orig_type == new_type)
1200       ASSERT_EQ (result, wrapped_orig_cst);
1201   }
1202 }
1203
1204 /* Verify that convert_to_integer_maybe_fold preserves locations.  */
1205
1206 static void
1207 test_convert_to_integer_maybe_fold ()
1208 {
1209   /* char -> long.  */
1210   test_convert_to_integer_maybe_fold (char_type_node, long_integer_type_node);
1211
1212   /* char -> char.  */
1213   test_convert_to_integer_maybe_fold (char_type_node, char_type_node);
1214
1215   /* long -> char.  */
1216   test_convert_to_integer_maybe_fold (char_type_node, long_integer_type_node);
1217
1218   /* long -> long.  */
1219   test_convert_to_integer_maybe_fold (long_integer_type_node,
1220                                       long_integer_type_node);
1221 }
1222
1223 /* Run all of the selftests within this file.  */
1224
1225 void
1226 convert_cc_tests ()
1227 {
1228   test_convert_to_integer_maybe_fold ();
1229 }
1230
1231 } // namespace selftest
1232
1233 #endif /* CHECKING_P */