gcc/convert.c

   1 /* Utility routines for data type conversion for GCC.
   2    Copyright (C) 1987-2020 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       {
  81         /* If the input precision differs from the target pointer type
  82            precision, first convert the input expression to an integer type of
  83            the target precision.  Some targets, e.g. VMS, need several pointer
  84            sizes to coexist so the latter isn't necessarily POINTER_SIZE.  */
  85         unsigned int pprec = TYPE_PRECISION (type);
  86         unsigned int eprec = TYPE_PRECISION (TREE_TYPE (expr));
  87
  88         if (eprec != pprec)
  89           expr
  90             = maybe_fold_build1_loc (fold_p, loc, NOP_EXPR,
  91                                      lang_hooks.types.type_for_size (pprec, 0),
  92                                      expr);
  93       }
  94       return maybe_fold_build1_loc (fold_p, loc, CONVERT_EXPR, type, expr);
  95
  96     default:
  97       error ("cannot convert to a pointer type");
  98       return convert_to_pointer_1 (type, integer_zero_node, fold_p);
  99     }
 100 }
 101
 102 /* Subroutine of the various convert_to_*_maybe_fold routines.
 103
 104    If a location wrapper has been folded to a constant (presumably of
 105    a different type), re-wrap the new constant with a location wrapper.  */
 106
 107 tree
 108 preserve_any_location_wrapper (tree result, tree orig_expr)
 109 {
 110   if (CONSTANT_CLASS_P (result) && location_wrapper_p (orig_expr))
 111     {
 112       if (result == TREE_OPERAND (orig_expr, 0))
 113         return orig_expr;
 114       else
 115         return maybe_wrap_with_location (result, EXPR_LOCATION (orig_expr));
 116     }
 117
 118   return result;
 119 }
 120
 121 /* A wrapper around convert_to_pointer_1 that always folds the
 122    expression.  */
 123
 124 tree
 125 convert_to_pointer (tree type, tree expr)
 126 {
 127   return convert_to_pointer_1 (type, expr, true);
 128 }
 129
 130 /* A wrapper around convert_to_pointer_1 that only folds the
 131    expression if DOFOLD, or if it is CONSTANT_CLASS_OR_WRAPPER_P.  */
 132
 133 tree
 134 convert_to_pointer_maybe_fold (tree type, tree expr, bool dofold)
 135 {
 136   tree result
 137     = convert_to_pointer_1 (type, expr,
 138                             dofold || CONSTANT_CLASS_OR_WRAPPER_P (expr));
 139   return preserve_any_location_wrapper (result, expr);
 140 }
 141
 142 /* Convert EXPR to some floating-point type TYPE.
 143
 144    EXPR must be float, fixed-point, integer, or enumeral;
 145    in other cases error is called.  If FOLD_P is true, try to fold
 146    the expression.  */
 147
 148 static tree
 149 convert_to_real_1 (tree type, tree expr, bool fold_p)
 150 {
 151   enum built_in_function fcode = builtin_mathfn_code (expr);
 152   tree itype = TREE_TYPE (expr);
 153   location_t loc = EXPR_LOCATION (expr);
 154
 155   if (TREE_CODE (expr) == COMPOUND_EXPR)
 156     {
 157       tree t = convert_to_real_1 (type, TREE_OPERAND (expr, 1), fold_p);
 158       if (t == TREE_OPERAND (expr, 1))
 159         return expr;
 160       return build2_loc (EXPR_LOCATION (expr), COMPOUND_EXPR, TREE_TYPE (t),
 161                          TREE_OPERAND (expr, 0), t);
 162     }
 163
 164   /* Disable until we figure out how to decide whether the functions are
 165      present in runtime.  */
 166   /* Convert (float)sqrt((double)x) where x is float into sqrtf(x) */
 167   if (optimize
 168       && (TYPE_MODE (type) == TYPE_MODE (double_type_node)
 169           || TYPE_MODE (type) == TYPE_MODE (float_type_node)))
 170     {
 171       switch (fcode)
 172         {
 173 #define CASE_MATHFN(FN) case BUILT_IN_##FN: case BUILT_IN_##FN##L:
 174           CASE_MATHFN (COSH)
 175           CASE_MATHFN (EXP)
 176           CASE_MATHFN (EXP10)
 177           CASE_MATHFN (EXP2)
 178           CASE_MATHFN (EXPM1)
 179           CASE_MATHFN (GAMMA)
 180           CASE_MATHFN (J0)
 181           CASE_MATHFN (J1)
 182           CASE_MATHFN (LGAMMA)
 183           CASE_MATHFN (POW10)
 184           CASE_MATHFN (SINH)
 185           CASE_MATHFN (TGAMMA)
 186           CASE_MATHFN (Y0)
 187           CASE_MATHFN (Y1)
 188             /* The above functions may set errno differently with float
 189                input or output so this transformation is not safe with
 190                -fmath-errno.  */
 191             if (flag_errno_math)
 192               break;
 193             gcc_fallthrough ();
 194           CASE_MATHFN (ACOS)
 195           CASE_MATHFN (ACOSH)
 196           CASE_MATHFN (ASIN)
 197           CASE_MATHFN (ASINH)
 198           CASE_MATHFN (ATAN)
 199           CASE_MATHFN (ATANH)
 200           CASE_MATHFN (CBRT)
 201           CASE_MATHFN (COS)
 202           CASE_MATHFN (ERF)
 203           CASE_MATHFN (ERFC)
 204           CASE_MATHFN (LOG)
 205           CASE_MATHFN (LOG10)
 206           CASE_MATHFN (LOG2)
 207           CASE_MATHFN (LOG1P)
 208           CASE_MATHFN (SIN)
 209           CASE_MATHFN (TAN)
 210           CASE_MATHFN (TANH)
 211             /* The above functions are not safe to do this conversion.  */
 212             if (!flag_unsafe_math_optimizations)
 213               break;
 214             gcc_fallthrough ();
 215           CASE_MATHFN (SQRT)
 216           CASE_MATHFN (FABS)
 217           CASE_MATHFN (LOGB)
 218 #undef CASE_MATHFN
 219             if (call_expr_nargs (expr) != 1
 220                 || !SCALAR_FLOAT_TYPE_P (TREE_TYPE (CALL_EXPR_ARG (expr, 0))))
 221               break;
 222             {
 223               tree arg0 = strip_float_extensions (CALL_EXPR_ARG (expr, 0));
 224               tree newtype = type;
 225
 226               /* We have (outertype)sqrt((innertype)x).  Choose the wider mode
 227                  from the both as the safe type for operation.  */
 228               if (TYPE_PRECISION (TREE_TYPE (arg0)) > TYPE_PRECISION (type))
 229                 newtype = TREE_TYPE (arg0);
 230
 231               /* We consider to convert
 232
 233                      (T1) sqrtT2 ((T2) exprT3)
 234                  to
 235                      (T1) sqrtT4 ((T4) exprT3)
 236
 237                   , where T1 is TYPE, T2 is ITYPE, T3 is TREE_TYPE (ARG0),
 238                  and T4 is NEWTYPE.  All those types are of floating-point types.
 239                  T4 (NEWTYPE) should be narrower than T2 (ITYPE). This conversion
 240                  is safe only if P1 >= P2*2+2, where P1 and P2 are precisions of
 241                  T2 and T4.  See the following URL for a reference:
 242                  http://stackoverflow.com/questions/9235456/determining-
 243                  floating-point-square-root
 244                  */
 245               if ((fcode == BUILT_IN_SQRT || fcode == BUILT_IN_SQRTL)
 246                   && !flag_unsafe_math_optimizations)
 247                 {
 248                   /* The following conversion is unsafe even the precision condition
 249                      below is satisfied:
 250
 251                      (float) sqrtl ((long double) double_val) -> (float) sqrt (double_val)
 252                     */
 253                   if (TYPE_MODE (type) != TYPE_MODE (newtype))
 254                     break;
 255
 256                   int p1 = REAL_MODE_FORMAT (TYPE_MODE (itype))->p;
 257                   int p2 = REAL_MODE_FORMAT (TYPE_MODE (newtype))->p;
 258                   if (p1 < p2 * 2 + 2)
 259                     break;
 260                 }
 261
 262               /* Be careful about integer to fp conversions.
 263                  These may overflow still.  */
 264               if (FLOAT_TYPE_P (TREE_TYPE (arg0))
 265                   && TYPE_PRECISION (newtype) < TYPE_PRECISION (itype)
 266                   && (TYPE_MODE (newtype) == TYPE_MODE (double_type_node)
 267                       || TYPE_MODE (newtype) == TYPE_MODE (float_type_node)))
 268                 {
 269                   tree fn = mathfn_built_in (newtype, fcode);
 270                   if (fn)
 271                     {
 272                       tree arg = convert_to_real_1 (newtype, arg0, fold_p);
 273                       expr = build_call_expr (fn, 1, arg);
 274                       if (newtype == type)
 275                         return expr;
 276                     }
 277                 }
 278             }
 279         default:
 280           break;
 281         }
 282     }
 283
 284   /* Propagate the cast into the operation.  */
 285   if (itype != type && FLOAT_TYPE_P (type))
 286     switch (TREE_CODE (expr))
 287       {
 288         /* Convert (float)-x into -(float)x.  This is safe for
 289            round-to-nearest rounding mode when the inner type is float.  */
 290         case ABS_EXPR:
 291         case NEGATE_EXPR:
 292           if (!flag_rounding_math
 293               && FLOAT_TYPE_P (itype)
 294               && TYPE_PRECISION (type) < TYPE_PRECISION (itype))
 295             {
 296               tree arg = convert_to_real_1 (type, TREE_OPERAND (expr, 0),
 297                                             fold_p);
 298               return build1 (TREE_CODE (expr), type, arg);
 299             }
 300           break;
 301         default:
 302           break;
 303       }
 304
 305   switch (TREE_CODE (TREE_TYPE (expr)))
 306     {
 307     case REAL_TYPE:
 308       /* Ignore the conversion if we don't need to store intermediate
 309          results and neither type is a decimal float.  */
 310       return build1_loc (loc,
 311                          (flag_float_store
 312                           || DECIMAL_FLOAT_TYPE_P (type)
 313                           || DECIMAL_FLOAT_TYPE_P (itype))
 314                          ? CONVERT_EXPR : NOP_EXPR, type, expr);
 315
 316     case INTEGER_TYPE:
 317     case ENUMERAL_TYPE:
 318     case BOOLEAN_TYPE:
 319       return build1 (FLOAT_EXPR, type, expr);
 320
 321     case FIXED_POINT_TYPE:
 322       return build1 (FIXED_CONVERT_EXPR, type, expr);
 323
 324     case COMPLEX_TYPE:
 325       return convert (type,
 326                       maybe_fold_build1_loc (fold_p, loc, REALPART_EXPR,
 327                                              TREE_TYPE (TREE_TYPE (expr)),
 328                                              expr));
 329
 330     case POINTER_TYPE:
 331     case REFERENCE_TYPE:
 332       error ("pointer value used where a floating-point was expected");
 333       return convert_to_real_1 (type, integer_zero_node, fold_p);
 334
 335     default:
 336       error ("aggregate value used where a floating-point was expected");
 337       return convert_to_real_1 (type, integer_zero_node, fold_p);
 338     }
 339 }
 340
 341 /* A wrapper around convert_to_real_1 that always folds the
 342    expression.  */
 343
 344 tree
 345 convert_to_real (tree type, tree expr)
 346 {
 347   return convert_to_real_1 (type, expr, true);
 348 }
 349
 350 /* A wrapper around convert_to_real_1 that only folds the
 351    expression if DOFOLD, or if it is CONSTANT_CLASS_OR_WRAPPER_P.  */
 352
 353 tree
 354 convert_to_real_maybe_fold (tree type, tree expr, bool dofold)
 355 {
 356   tree result
 357     = convert_to_real_1 (type, expr,
 358                          dofold || CONSTANT_CLASS_OR_WRAPPER_P (expr));
 359   return preserve_any_location_wrapper (result, expr);
 360 }
 361
 362 /* Try to narrow EX_FORM ARG0 ARG1 in narrowed arg types producing a
 363    result in TYPE.  */
 364
 365 static tree
 366 do_narrow (location_t loc,
 367            enum tree_code ex_form, tree type, tree arg0, tree arg1,
 368            tree expr, unsigned inprec, unsigned outprec, bool dofold)
 369 {
 370   /* Do the arithmetic in type TYPEX,
 371      then convert result to TYPE.  */
 372   tree typex = type;
 373
 374   /* Can't do arithmetic in enumeral types
 375      so use an integer type that will hold the values.  */
 376   if (TREE_CODE (typex) == ENUMERAL_TYPE)
 377     typex = lang_hooks.types.type_for_size (TYPE_PRECISION (typex),
 378                                             TYPE_UNSIGNED (typex));
 379
 380   /* The type demotion below might cause doing unsigned arithmetic
 381      instead of signed, and thus hide overflow bugs.  */
 382   if ((ex_form == PLUS_EXPR || ex_form == MINUS_EXPR)
 383       && !TYPE_UNSIGNED (typex)
 384       && sanitize_flags_p (SANITIZE_SI_OVERFLOW))
 385     return NULL_TREE;
 386
 387   /* But now perhaps TYPEX is as wide as INPREC.
 388      In that case, do nothing special here.
 389      (Otherwise would recurse infinitely in convert.  */
 390   if (TYPE_PRECISION (typex) != inprec)
 391     {
 392       /* Don't do unsigned arithmetic where signed was wanted,
 393          or vice versa.
 394          Exception: if both of the original operands were
 395          unsigned then we can safely do the work as unsigned.
 396          Exception: shift operations take their type solely
 397          from the first argument.
 398          Exception: the LSHIFT_EXPR case above requires that
 399          we perform this operation unsigned lest we produce
 400          signed-overflow undefinedness.
 401          And we may need to do it as unsigned
 402          if we truncate to the original size.  */
 403       if (TYPE_UNSIGNED (TREE_TYPE (expr))
 404           || (TYPE_UNSIGNED (TREE_TYPE (arg0))
 405               && (TYPE_UNSIGNED (TREE_TYPE (arg1))
 406                   || ex_form == LSHIFT_EXPR
 407                   || ex_form == RSHIFT_EXPR
 408                   || ex_form == LROTATE_EXPR
 409                   || ex_form == RROTATE_EXPR))
 410           || ex_form == LSHIFT_EXPR
 411           /* If we have !flag_wrapv, and either ARG0 or
 412              ARG1 is of a signed type, we have to do
 413              PLUS_EXPR, MINUS_EXPR or MULT_EXPR in an unsigned
 414              type in case the operation in outprec precision
 415              could overflow.  Otherwise, we would introduce
 416              signed-overflow undefinedness.  */
 417           || ((!(INTEGRAL_TYPE_P (TREE_TYPE (arg0))
 418                  && TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0)))
 419                || !(INTEGRAL_TYPE_P (TREE_TYPE (arg1))
 420                     && TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg1))))
 421               && ((TYPE_PRECISION (TREE_TYPE (arg0)) * 2u
 422                    > outprec)
 423                   || (TYPE_PRECISION (TREE_TYPE (arg1)) * 2u
 424                       > outprec))
 425               && (ex_form == PLUS_EXPR
 426                   || ex_form == MINUS_EXPR
 427                   || ex_form == MULT_EXPR)))
 428         {
 429           if (!TYPE_UNSIGNED (typex))
 430             typex = unsigned_type_for (typex);
 431         }
 432       else
 433         {
 434           if (TYPE_UNSIGNED (typex))
 435             typex = signed_type_for (typex);
 436         }
 437       /* We should do away with all this once we have a proper
 438          type promotion/demotion pass, see PR45397.  */
 439       expr = maybe_fold_build2_loc (dofold, loc, ex_form, typex,
 440                                     convert (typex, arg0),
 441                                     convert (typex, arg1));
 442       return convert (type, expr);
 443     }
 444
 445   return NULL_TREE;
 446 }
 447
 448 /* Convert EXPR to some integer (or enum) type TYPE.
 449
 450    EXPR must be pointer, integer, discrete (enum, char, or bool), float,
 451    fixed-point or vector; in other cases error is called.
 452
 453    If DOFOLD is TRUE, we try to simplify newly-created patterns by folding.
 454
 455    The result of this is always supposed to be a newly created tree node
 456    not in use in any existing structure.  */
 457
 458 static tree
 459 convert_to_integer_1 (tree type, tree expr, bool dofold)
 460 {
 461   enum tree_code ex_form = TREE_CODE (expr);
 462   tree intype = TREE_TYPE (expr);
 463   unsigned int inprec = element_precision (intype);
 464   unsigned int outprec = element_precision (type);
 465   location_t loc = EXPR_LOCATION (expr);
 466
 467   /* An INTEGER_TYPE cannot be incomplete, but an ENUMERAL_TYPE can
 468      be.  Consider `enum E = { a, b = (enum E) 3 };'.  */
 469   if (!COMPLETE_TYPE_P (type))
 470     {
 471       error ("conversion to incomplete type");
 472       return error_mark_node;
 473     }
 474
 475   if (ex_form == COMPOUND_EXPR)
 476     {
 477       tree t = convert_to_integer_1 (type, TREE_OPERAND (expr, 1), dofold);
 478       if (t == TREE_OPERAND (expr, 1))
 479         return expr;
 480       return build2_loc (EXPR_LOCATION (expr), COMPOUND_EXPR, TREE_TYPE (t),
 481                          TREE_OPERAND (expr, 0), t);
 482     }
 483
 484   /* Convert e.g. (long)round(d) -> lround(d).  */
 485   /* If we're converting to char, we may encounter differing behavior
 486      between converting from double->char vs double->long->char.
 487      We're in "undefined" territory but we prefer to be conservative,
 488      so only proceed in "unsafe" math mode.  */
 489   if (optimize
 490       && (flag_unsafe_math_optimizations
 491           || (long_integer_type_node
 492               && outprec >= TYPE_PRECISION (long_integer_type_node))))
 493     {
 494       tree s_expr = strip_float_extensions (expr);
 495       tree s_intype = TREE_TYPE (s_expr);
 496       const enum built_in_function fcode = builtin_mathfn_code (s_expr);
 497       tree fn = 0;
 498
 499       switch (fcode)
 500         {
 501         CASE_FLT_FN (BUILT_IN_CEIL):
 502         CASE_FLT_FN_FLOATN_NX (BUILT_IN_CEIL):
 503           /* Only convert in ISO C99 mode.  */
 504           if (!targetm.libc_has_function (function_c99_misc))
 505             break;
 506           if (outprec < TYPE_PRECISION (integer_type_node)
 507               || (outprec == TYPE_PRECISION (integer_type_node)
 508                   && !TYPE_UNSIGNED (type)))
 509             fn = mathfn_built_in (s_intype, BUILT_IN_ICEIL);
 510           else if (outprec == TYPE_PRECISION (long_integer_type_node)
 511                    && !TYPE_UNSIGNED (type))
 512             fn = mathfn_built_in (s_intype, BUILT_IN_LCEIL);
 513           else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
 514                    && !TYPE_UNSIGNED (type))
 515             fn = mathfn_built_in (s_intype, BUILT_IN_LLCEIL);
 516           break;
 517
 518         CASE_FLT_FN (BUILT_IN_FLOOR):
 519         CASE_FLT_FN_FLOATN_NX (BUILT_IN_FLOOR):
 520           /* Only convert in ISO C99 mode.  */
 521           if (!targetm.libc_has_function (function_c99_misc))
 522             break;
 523           if (outprec < TYPE_PRECISION (integer_type_node)
 524               || (outprec == TYPE_PRECISION (integer_type_node)
 525                   && !TYPE_UNSIGNED (type)))
 526             fn = mathfn_built_in (s_intype, BUILT_IN_IFLOOR);
 527           else if (outprec == TYPE_PRECISION (long_integer_type_node)
 528                    && !TYPE_UNSIGNED (type))
 529             fn = mathfn_built_in (s_intype, BUILT_IN_LFLOOR);
 530           else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
 531                    && !TYPE_UNSIGNED (type))
 532             fn = mathfn_built_in (s_intype, BUILT_IN_LLFLOOR);
 533           break;
 534
 535         CASE_FLT_FN (BUILT_IN_ROUND):
 536         CASE_FLT_FN_FLOATN_NX (BUILT_IN_ROUND):
 537           /* Only convert in ISO C99 mode and with -fno-math-errno.  */
 538           if (!targetm.libc_has_function (function_c99_misc)
 539               || flag_errno_math)
 540             break;
 541           if (outprec < TYPE_PRECISION (integer_type_node)
 542               || (outprec == TYPE_PRECISION (integer_type_node)
 543                   && !TYPE_UNSIGNED (type)))
 544             fn = mathfn_built_in (s_intype, BUILT_IN_IROUND);
 545           else if (outprec == TYPE_PRECISION (long_integer_type_node)
 546                    && !TYPE_UNSIGNED (type))
 547             fn = mathfn_built_in (s_intype, BUILT_IN_LROUND);
 548           else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
 549                    && !TYPE_UNSIGNED (type))
 550             fn = mathfn_built_in (s_intype, BUILT_IN_LLROUND);
 551           break;
 552
 553         CASE_FLT_FN (BUILT_IN_NEARBYINT):
 554         CASE_FLT_FN_FLOATN_NX (BUILT_IN_NEARBYINT):
 555           /* Only convert nearbyint* if we can ignore math exceptions.  */
 556           if (flag_trapping_math)
 557             break;
 558           gcc_fallthrough ();
 559         CASE_FLT_FN (BUILT_IN_RINT):
 560         CASE_FLT_FN_FLOATN_NX (BUILT_IN_RINT):
 561           /* Only convert in ISO C99 mode and with -fno-math-errno.  */
 562           if (!targetm.libc_has_function (function_c99_misc)
 563               || flag_errno_math)
 564             break;
 565           if (outprec < TYPE_PRECISION (integer_type_node)
 566               || (outprec == TYPE_PRECISION (integer_type_node)
 567                   && !TYPE_UNSIGNED (type)))
 568             fn = mathfn_built_in (s_intype, BUILT_IN_IRINT);
 569           else if (outprec == TYPE_PRECISION (long_integer_type_node)
 570                    && !TYPE_UNSIGNED (type))
 571             fn = mathfn_built_in (s_intype, BUILT_IN_LRINT);
 572           else if (outprec == TYPE_PRECISION (long_long_integer_type_node)
 573                    && !TYPE_UNSIGNED (type))
 574             fn = mathfn_built_in (s_intype, BUILT_IN_LLRINT);
 575           break;
 576
 577         CASE_FLT_FN (BUILT_IN_TRUNC):
 578         CASE_FLT_FN_FLOATN_NX (BUILT_IN_TRUNC):
 579           if (call_expr_nargs (s_expr) != 1
 580               || !SCALAR_FLOAT_TYPE_P (TREE_TYPE (CALL_EXPR_ARG (s_expr, 0))))
 581             break;
 582           return convert_to_integer_1 (type, CALL_EXPR_ARG (s_expr, 0),
 583                                        dofold);
 584
 585         default:
 586           break;
 587         }
 588
 589       if (fn
 590           && call_expr_nargs (s_expr) == 1
 591           && SCALAR_FLOAT_TYPE_P (TREE_TYPE (CALL_EXPR_ARG (s_expr, 0))))
 592         {
 593           tree newexpr = build_call_expr (fn, 1, CALL_EXPR_ARG (s_expr, 0));
 594           return convert_to_integer_1 (type, newexpr, dofold);
 595         }
 596     }
 597
 598   /* Convert (int)logb(d) -> ilogb(d).  */
 599   if (optimize
 600       && flag_unsafe_math_optimizations
 601       && !flag_trapping_math && !flag_errno_math && flag_finite_math_only
 602       && integer_type_node
 603       && (outprec > TYPE_PRECISION (integer_type_node)
 604           || (outprec == TYPE_PRECISION (integer_type_node)
 605               && !TYPE_UNSIGNED (type))))
 606     {
 607       tree s_expr = strip_float_extensions (expr);
 608       tree s_intype = TREE_TYPE (s_expr);
 609       const enum built_in_function fcode = builtin_mathfn_code (s_expr);
 610       tree fn = 0;
 611
 612       switch (fcode)
 613         {
 614         CASE_FLT_FN (BUILT_IN_LOGB):
 615           fn = mathfn_built_in (s_intype, BUILT_IN_ILOGB);
 616           break;
 617
 618         default:
 619           break;
 620         }
 621
 622       if (fn
 623           && call_expr_nargs (s_expr) == 1
 624           && SCALAR_FLOAT_TYPE_P (TREE_TYPE (CALL_EXPR_ARG (s_expr, 0))))
 625         {
 626           tree newexpr = build_call_expr (fn, 1, CALL_EXPR_ARG (s_expr, 0));
 627           return convert_to_integer_1 (type, newexpr, dofold);
 628         }
 629     }
 630
 631   switch (TREE_CODE (intype))
 632     {
 633     case POINTER_TYPE:
 634     case REFERENCE_TYPE:
 635       if (integer_zerop (expr)
 636           && !TREE_OVERFLOW (tree_strip_any_location_wrapper (expr)))
 637         return build_int_cst (type, 0);
 638
 639       /* Convert to an unsigned integer of the correct width first, and from
 640          there widen/truncate to the required type.  Some targets support the
 641          coexistence of multiple valid pointer sizes, so fetch the one we need
 642          from the type.  */
 643       if (!dofold)
 644         return build1 (CONVERT_EXPR, type, expr);
 645       expr = fold_build1 (CONVERT_EXPR,
 646                           lang_hooks.types.type_for_size
 647                             (TYPE_PRECISION (intype), 0),
 648                           expr);
 649       return fold_convert (type, expr);
 650
 651     case INTEGER_TYPE:
 652     case ENUMERAL_TYPE:
 653     case BOOLEAN_TYPE:
 654     case OFFSET_TYPE:
 655       /* If this is a logical operation, which just returns 0 or 1, we can
 656          change the type of the expression.  */
 657
 658       if (TREE_CODE_CLASS (ex_form) == tcc_comparison)
 659         {
 660           expr = copy_node (expr);
 661           TREE_TYPE (expr) = type;
 662           return expr;
 663         }
 664
 665       /* If we are widening the type, put in an explicit conversion.
 666          Similarly if we are not changing the width.  After this, we know
 667          we are truncating EXPR.  */
 668
 669       else if (outprec >= inprec)
 670         {
 671           enum tree_code code;
 672
 673           /* If the precision of the EXPR's type is K bits and the
 674              destination mode has more bits, and the sign is changing,
 675              it is not safe to use a NOP_EXPR.  For example, suppose
 676              that EXPR's type is a 3-bit unsigned integer type, the
 677              TYPE is a 3-bit signed integer type, and the machine mode
 678              for the types is 8-bit QImode.  In that case, the
 679              conversion necessitates an explicit sign-extension.  In
 680              the signed-to-unsigned case the high-order bits have to
 681              be cleared.  */
 682           if (TYPE_UNSIGNED (type) != TYPE_UNSIGNED (TREE_TYPE (expr))
 683               && !type_has_mode_precision_p (TREE_TYPE (expr)))
 684             code = CONVERT_EXPR;
 685           else
 686             code = NOP_EXPR;
 687
 688           return maybe_fold_build1_loc (dofold, loc, code, type, expr);
 689         }
 690
 691       /* If TYPE is an enumeral type or a type with a precision less
 692          than the number of bits in its mode, do the conversion to the
 693          type corresponding to its mode, then do a nop conversion
 694          to TYPE.  */
 695       else if (TREE_CODE (type) == ENUMERAL_TYPE
 696                || maybe_ne (outprec, GET_MODE_PRECISION (TYPE_MODE (type))))
 697         {
 698           expr
 699             = convert_to_integer_1 (lang_hooks.types.type_for_mode
 700                                     (TYPE_MODE (type), TYPE_UNSIGNED (type)),
 701                                     expr, dofold);
 702           return maybe_fold_build1_loc (dofold, loc, NOP_EXPR, type, expr);
 703         }
 704
 705       /* Here detect when we can distribute the truncation down past some
 706          arithmetic.  For example, if adding two longs and converting to an
 707          int, we can equally well convert both to ints and then add.
 708          For the operations handled here, such truncation distribution
 709          is always safe.
 710          It is desirable in these cases:
 711          1) when truncating down to full-word from a larger size
 712          2) when truncating takes no work.
 713          3) when at least one operand of the arithmetic has been extended
 714          (as by C's default conversions).  In this case we need two conversions
 715          if we do the arithmetic as already requested, so we might as well
 716          truncate both and then combine.  Perhaps that way we need only one.
 717
 718          Note that in general we cannot do the arithmetic in a type
 719          shorter than the desired result of conversion, even if the operands
 720          are both extended from a shorter type, because they might overflow
 721          if combined in that type.  The exceptions to this--the times when
 722          two narrow values can be combined in their narrow type even to
 723          make a wider result--are handled by "shorten" in build_binary_op.  */
 724
 725       if (dofold)
 726         switch (ex_form)
 727           {
 728           case RSHIFT_EXPR:
 729             /* We can pass truncation down through right shifting
 730                when the shift count is a nonpositive constant.  */
 731             if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST
 732                 && tree_int_cst_sgn (TREE_OPERAND (expr, 1)) <= 0)
 733               goto trunc1;
 734             break;
 735
 736           case LSHIFT_EXPR:
 737             /* We can pass truncation down through left shifting
 738                when the shift count is a nonnegative constant and
 739                the target type is unsigned.  */
 740             if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST
 741                 && tree_int_cst_sgn (TREE_OPERAND (expr, 1)) >= 0
 742                 && TYPE_UNSIGNED (type)
 743                 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
 744               {
 745                 /* If shift count is less than the width of the truncated type,
 746                    really shift.  */
 747                 if (tree_int_cst_lt (TREE_OPERAND (expr, 1), TYPE_SIZE (type)))
 748                   /* In this case, shifting is like multiplication.  */
 749                   goto trunc1;
 750                 else
 751                   {
 752                     /* If it is >= that width, result is zero.
 753                        Handling this with trunc1 would give the wrong result:
 754                        (int) ((long long) a << 32) is well defined (as 0)
 755                        but (int) a << 32 is undefined and would get a
 756                        warning.  */
 757
 758                     tree t = build_int_cst (type, 0);
 759
 760                     /* If the original expression had side-effects, we must
 761                        preserve it.  */
 762                     if (TREE_SIDE_EFFECTS (expr))
 763                       return build2 (COMPOUND_EXPR, type, expr, t);
 764                     else
 765                       return t;
 766                   }
 767               }
 768             break;
 769
 770           case TRUNC_DIV_EXPR:
 771             {
 772               tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), NULL_TREE);
 773               tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), NULL_TREE);
 774
 775               /* Don't distribute unless the output precision is at least as
 776                  big as the actual inputs and it has the same signedness.  */
 777               if (outprec >= TYPE_PRECISION (TREE_TYPE (arg0))
 778                   && outprec >= TYPE_PRECISION (TREE_TYPE (arg1))
 779                   /* If signedness of arg0 and arg1 don't match,
 780                      we can't necessarily find a type to compare them in.  */
 781                   && (TYPE_UNSIGNED (TREE_TYPE (arg0))
 782                       == TYPE_UNSIGNED (TREE_TYPE (arg1)))
 783                   /* Do not change the sign of the division.  */
 784                   && (TYPE_UNSIGNED (TREE_TYPE (expr))
 785                       == TYPE_UNSIGNED (TREE_TYPE (arg0)))
 786                   /* Either require unsigned division or a division by
 787                      a constant that is not -1.  */
 788                   && (TYPE_UNSIGNED (TREE_TYPE (arg0))
 789                       || (TREE_CODE (arg1) == INTEGER_CST
 790                           && !integer_all_onesp (arg1))))
 791                 {
 792                   tree tem = do_narrow (loc, ex_form, type, arg0, arg1,
 793                                         expr, inprec, outprec, dofold);
 794                   if (tem)
 795                     return tem;
 796                 }
 797               break;
 798             }
 799
 800           case MAX_EXPR:
 801           case MIN_EXPR:
 802           case MULT_EXPR:
 803             {
 804               tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type);
 805               tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type);
 806
 807               /* Don't distribute unless the output precision is at least as
 808                  big as the actual inputs.  Otherwise, the comparison of the
 809                  truncated values will be wrong.  */
 810               if (outprec >= TYPE_PRECISION (TREE_TYPE (arg0))
 811                   && outprec >= TYPE_PRECISION (TREE_TYPE (arg1))
 812                   /* If signedness of arg0 and arg1 don't match,
 813                      we can't necessarily find a type to compare them in.  */
 814                   && (TYPE_UNSIGNED (TREE_TYPE (arg0))
 815                       == TYPE_UNSIGNED (TREE_TYPE (arg1))))
 816                 goto trunc1;
 817               break;
 818             }
 819
 820           case PLUS_EXPR:
 821           case MINUS_EXPR:
 822           case BIT_AND_EXPR:
 823           case BIT_IOR_EXPR:
 824           case BIT_XOR_EXPR:
 825           trunc1:
 826             {
 827               tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type);
 828               tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type);
 829
 830               /* Do not try to narrow operands of pointer subtraction;
 831                  that will interfere with other folding.  */
 832               if (ex_form == MINUS_EXPR
 833                   && CONVERT_EXPR_P (arg0)
 834                   && CONVERT_EXPR_P (arg1)
 835                   && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 0)))
 836                   && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (arg1, 0))))
 837                 break;
 838
 839               if (outprec >= BITS_PER_WORD
 840                   || targetm.truly_noop_truncation (outprec, inprec)
 841                   || inprec > TYPE_PRECISION (TREE_TYPE (arg0))
 842                   || inprec > TYPE_PRECISION (TREE_TYPE (arg1)))
 843                 {
 844                   tree tem = do_narrow (loc, ex_form, type, arg0, arg1,
 845                                         expr, inprec, outprec, dofold);
 846                   if (tem)
 847                     return tem;
 848                 }
 849             }
 850             break;
 851
 852           case NEGATE_EXPR:
 853             /* Using unsigned arithmetic for signed types may hide overflow
 854                bugs.  */
 855             if (!TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (expr, 0)))
 856                 && sanitize_flags_p (SANITIZE_SI_OVERFLOW))
 857               break;
 858             /* Fall through.  */
 859           case BIT_NOT_EXPR:
 860             /* This is not correct for ABS_EXPR,
 861                since we must test the sign before truncation.  */
 862             {
 863               /* Do the arithmetic in type TYPEX,
 864                  then convert result to TYPE.  */
 865               tree typex = type;
 866
 867               /* Can't do arithmetic in enumeral types
 868                  so use an integer type that will hold the values.  */
 869               if (TREE_CODE (typex) == ENUMERAL_TYPE)
 870                 typex
 871                   = lang_hooks.types.type_for_size (TYPE_PRECISION (typex),
 872                                                     TYPE_UNSIGNED (typex));
 873
 874               if (!TYPE_UNSIGNED (typex))
 875                 typex = unsigned_type_for (typex);
 876               return convert (type,
 877                               fold_build1 (ex_form, typex,
 878                                            convert (typex,
 879                                                     TREE_OPERAND (expr, 0))));
 880             }
 881
 882           CASE_CONVERT:
 883             {
 884               tree argtype = TREE_TYPE (TREE_OPERAND (expr, 0));
 885               /* Don't introduce a "can't convert between vector values
 886                  of different size" error.  */
 887               if (TREE_CODE (argtype) == VECTOR_TYPE
 888                   && maybe_ne (GET_MODE_SIZE (TYPE_MODE (argtype)),
 889                                GET_MODE_SIZE (TYPE_MODE (type))))
 890                 break;
 891             }
 892             /* If truncating after truncating, might as well do all at once.
 893                If truncating after extending, we may get rid of wasted work.  */
 894             return convert (type, get_unwidened (TREE_OPERAND (expr, 0), type));
 895
 896           case COND_EXPR:
 897             /* It is sometimes worthwhile to push the narrowing down through
 898                the conditional and never loses.  A COND_EXPR may have a throw
 899                as one operand, which then has void type.  Just leave void
 900                operands as they are.  */
 901             return
 902               fold_build3 (COND_EXPR, type, TREE_OPERAND (expr, 0),
 903                            VOID_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 1)))
 904                            ? TREE_OPERAND (expr, 1)
 905                            : convert (type, TREE_OPERAND (expr, 1)),
 906                            VOID_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 2)))
 907                            ? TREE_OPERAND (expr, 2)
 908                            : convert (type, TREE_OPERAND (expr, 2)));
 909
 910           default:
 911             break;
 912           }
 913
 914       /* When parsing long initializers, we might end up with a lot of casts.
 915          Shortcut this.  */
 916       if (TREE_CODE (tree_strip_any_location_wrapper (expr)) == INTEGER_CST)
 917         return fold_convert (type, expr);
 918       return build1 (CONVERT_EXPR, type, expr);
 919
 920     case REAL_TYPE:
 921       if (sanitize_flags_p (SANITIZE_FLOAT_CAST)
 922           && current_function_decl != NULL_TREE)
 923         {
 924           expr = save_expr (expr);
 925           tree check = ubsan_instrument_float_cast (loc, type, expr);
 926           expr = build1 (FIX_TRUNC_EXPR, type, expr);
 927           if (check == NULL_TREE)
 928             return expr;
 929           return maybe_fold_build2_loc (dofold, loc, COMPOUND_EXPR,
 930                                         TREE_TYPE (expr), check, expr);
 931         }
 932       else
 933         return build1 (FIX_TRUNC_EXPR, type, expr);
 934
 935     case FIXED_POINT_TYPE:
 936       return build1 (FIXED_CONVERT_EXPR, type, expr);
 937
 938     case COMPLEX_TYPE:
 939       expr = maybe_fold_build1_loc (dofold, loc, REALPART_EXPR,
 940                                     TREE_TYPE (TREE_TYPE (expr)), expr);
 941       return convert (type, expr);
 942
 943     case VECTOR_TYPE:
 944       if (!tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (TREE_TYPE (expr))))
 945         {
 946           error ("cannot convert a vector of type %qT"
 947                  " to type %qT which has different size",
 948                  TREE_TYPE (expr), type);
 949           return error_mark_node;
 950         }
 951       return build1 (VIEW_CONVERT_EXPR, type, expr);
 952
 953     default:
 954       error ("aggregate value used where an integer was expected");
 955       return convert (type, integer_zero_node);
 956     }
 957 }
 958
 959 /* Convert EXPR to some integer (or enum) type TYPE.
 960
 961    EXPR must be pointer, integer, discrete (enum, char, or bool), float,
 962    fixed-point or vector; in other cases error is called.
 963
 964    The result of this is always supposed to be a newly created tree node
 965    not in use in any existing structure.  */
 966
 967 tree
 968 convert_to_integer (tree type, tree expr)
 969 {
 970   return convert_to_integer_1 (type, expr, true);
 971 }
 972
 973 /* A wrapper around convert_to_complex_1 that only folds the
 974    expression if DOFOLD, or if it is CONSTANT_CLASS_OR_WRAPPER_P.  */
 975
 976 tree
 977 convert_to_integer_maybe_fold (tree type, tree expr, bool dofold)
 978 {
 979   tree result
 980     = convert_to_integer_1 (type, expr,
 981                             dofold || CONSTANT_CLASS_OR_WRAPPER_P (expr));
 982   return preserve_any_location_wrapper (result, expr);
 983 }
 984
 985 /* Convert EXPR to the complex type TYPE in the usual ways.  If FOLD_P is
 986    true, try to fold the expression.  */
 987
 988 static tree
 989 convert_to_complex_1 (tree type, tree expr, bool fold_p)
 990 {
 991   location_t loc = EXPR_LOCATION (expr);
 992   tree subtype = TREE_TYPE (type);
 993
 994   switch (TREE_CODE (TREE_TYPE (expr)))
 995     {
 996     case REAL_TYPE:
 997     case FIXED_POINT_TYPE:
 998     case INTEGER_TYPE:
 999     case ENUMERAL_TYPE:
1000     case BOOLEAN_TYPE:
1001       return build2 (COMPLEX_EXPR, type, convert (subtype, expr),
1002                      convert (subtype, integer_zero_node));
1003
1004     case COMPLEX_TYPE:
1005       {
1006         tree elt_type = TREE_TYPE (TREE_TYPE (expr));
1007
1008         if (TYPE_MAIN_VARIANT (elt_type) == TYPE_MAIN_VARIANT (subtype))
1009           return expr;
1010         else if (TREE_CODE (expr) == COMPOUND_EXPR)
1011           {
1012             tree t = convert_to_complex_1 (type, TREE_OPERAND (expr, 1),
1013                                            fold_p);
1014             if (t == TREE_OPERAND (expr, 1))
1015               return expr;
1016             return build2_loc (EXPR_LOCATION (expr), COMPOUND_EXPR,
1017                                TREE_TYPE (t), TREE_OPERAND (expr, 0), t);
1018           }
1019         else if (TREE_CODE (expr) == COMPLEX_EXPR)
1020           return maybe_fold_build2_loc (fold_p, loc, COMPLEX_EXPR, type,
1021                                         convert (subtype,
1022                                                  TREE_OPERAND (expr, 0)),
1023                                         convert (subtype,
1024                                                  TREE_OPERAND (expr, 1)));
1025         else
1026           {
1027             expr = save_expr (expr);
1028             tree realp = maybe_fold_build1_loc (fold_p, loc, REALPART_EXPR,
1029                                                 TREE_TYPE (TREE_TYPE (expr)),
1030                                                 expr);
1031             tree imagp = maybe_fold_build1_loc (fold_p, loc, IMAGPART_EXPR,
1032                                                 TREE_TYPE (TREE_TYPE (expr)),
1033                                                 expr);
1034             return maybe_fold_build2_loc (fold_p, loc, COMPLEX_EXPR, type,
1035                                           convert (subtype, realp),
1036                                           convert (subtype, imagp));
1037           }
1038       }
1039
1040     case POINTER_TYPE:
1041     case REFERENCE_TYPE:
1042       error ("pointer value used where a complex was expected");
1043       return convert_to_complex_1 (type, integer_zero_node, fold_p);
1044
1045     default:
1046       error ("aggregate value used where a complex was expected");
1047       return convert_to_complex_1 (type, integer_zero_node, fold_p);
1048     }
1049 }
1050
1051 /* A wrapper around convert_to_complex_1 that always folds the
1052    expression.  */
1053
1054 tree
1055 convert_to_complex (tree type, tree expr)
1056 {
1057   return convert_to_complex_1 (type, expr, true);
1058 }
1059
1060 /* A wrapper around convert_to_complex_1 that only folds the
1061    expression if DOFOLD, or if it is CONSTANT_CLASS_OR_WRAPPER_P.  */
1062
1063 tree
1064 convert_to_complex_maybe_fold (tree type, tree expr, bool dofold)
1065 {
1066   tree result
1067     = convert_to_complex_1 (type, expr,
1068                             dofold || CONSTANT_CLASS_OR_WRAPPER_P (expr));
1069   return preserve_any_location_wrapper (result, expr);
1070 }
1071
1072 /* Convert EXPR to the vector type TYPE in the usual ways.  */
1073
1074 tree
1075 convert_to_vector (tree type, tree expr)
1076 {
1077   switch (TREE_CODE (TREE_TYPE (expr)))
1078     {
1079     case INTEGER_TYPE:
1080     case VECTOR_TYPE:
1081       if (!tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (TREE_TYPE (expr))))
1082         {
1083           error ("cannot convert a value of type %qT"
1084                  " to vector type %qT which has different size",
1085                  TREE_TYPE (expr), type);
1086           return error_mark_node;
1087         }
1088       return build1 (VIEW_CONVERT_EXPR, type, expr);
1089
1090     default:
1091       error ("cannot convert value to a vector");
1092       return error_mark_node;
1093     }
1094 }
1095
1096 /* Convert EXPR to some fixed-point type TYPE.
1097
1098    EXPR must be fixed-point, float, integer, or enumeral;
1099    in other cases error is called.  */
1100
1101 tree
1102 convert_to_fixed (tree type, tree expr)
1103 {
1104   if (integer_zerop (expr))
1105     {
1106       tree fixed_zero_node = build_fixed (type, FCONST0 (TYPE_MODE (type)));
1107       return fixed_zero_node;
1108     }
1109   else if (integer_onep (expr) && ALL_SCALAR_ACCUM_MODE_P (TYPE_MODE (type)))
1110     {
1111       tree fixed_one_node = build_fixed (type, FCONST1 (TYPE_MODE (type)));
1112       return fixed_one_node;
1113     }
1114
1115   switch (TREE_CODE (TREE_TYPE (expr)))
1116     {
1117     case FIXED_POINT_TYPE:
1118     case INTEGER_TYPE:
1119     case ENUMERAL_TYPE:
1120     case BOOLEAN_TYPE:
1121     case REAL_TYPE:
1122       return build1 (FIXED_CONVERT_EXPR, type, expr);
1123
1124     case COMPLEX_TYPE:
1125       return convert (type,
1126                       fold_build1 (REALPART_EXPR,
1127                                    TREE_TYPE (TREE_TYPE (expr)), expr));
1128
1129     default:
1130       error ("aggregate value used where a fixed-point was expected");
1131       return error_mark_node;
1132     }
1133 }
1134
1135 #if CHECKING_P
1136
1137 namespace selftest {
1138
1139 /* Selftests for conversions.  */
1140
1141 static void
1142 test_convert_to_integer_maybe_fold (tree orig_type, tree new_type)
1143 {
1144   /* Calling convert_to_integer_maybe_fold on an INTEGER_CST.  */
1145
1146   tree orig_cst = build_int_cst (orig_type, 42);
1147
1148   /* Verify that convert_to_integer_maybe_fold on a constant returns a new
1149      constant of the new type, unless the types are the same, in which
1150      case verify it's a no-op.  */
1151   {
1152     tree result = convert_to_integer_maybe_fold (new_type,
1153                                                  orig_cst, false);
1154     if (orig_type != new_type)
1155       {
1156         ASSERT_EQ (TREE_TYPE (result), new_type);
1157         ASSERT_EQ (TREE_CODE (result), INTEGER_CST);
1158       }
1159     else
1160       ASSERT_EQ (result, orig_cst);
1161   }
1162
1163   /* Calling convert_to_integer_maybe_fold on a location wrapper around
1164      an INTEGER_CST.
1165
1166      Verify that convert_to_integer_maybe_fold on a location wrapper
1167      around a constant returns a new location wrapper around an equivalent
1168      constant, both of the new type, unless the types are the same,
1169      in which case the original wrapper should be returned.   */
1170   {
1171     const location_t loc = BUILTINS_LOCATION;
1172     tree wrapped_orig_cst = maybe_wrap_with_location (orig_cst, loc);
1173     tree result
1174       = convert_to_integer_maybe_fold (new_type, wrapped_orig_cst, false);
1175     ASSERT_EQ (TREE_TYPE (result), new_type);
1176     ASSERT_EQ (EXPR_LOCATION (result), loc);
1177     ASSERT_TRUE (location_wrapper_p (result));
1178     ASSERT_EQ (TREE_TYPE (TREE_OPERAND (result, 0)), new_type);
1179     ASSERT_EQ (TREE_CODE (TREE_OPERAND (result, 0)), INTEGER_CST);
1180
1181     if (orig_type == new_type)
1182       ASSERT_EQ (result, wrapped_orig_cst);
1183   }
1184 }
1185
1186 /* Verify that convert_to_integer_maybe_fold preserves locations.  */
1187
1188 static void
1189 test_convert_to_integer_maybe_fold ()
1190 {
1191   /* char -> long.  */
1192   test_convert_to_integer_maybe_fold (char_type_node, long_integer_type_node);
1193
1194   /* char -> char.  */
1195   test_convert_to_integer_maybe_fold (char_type_node, char_type_node);
1196
1197   /* long -> char.  */
1198   test_convert_to_integer_maybe_fold (char_type_node, long_integer_type_node);
1199
1200   /* long -> long.  */
1201   test_convert_to_integer_maybe_fold (long_integer_type_node,
1202                                       long_integer_type_node);
1203 }
1204
1205 /* Run all of the selftests within this file.  */
1206
1207 void
1208 convert_c_tests ()
1209 {
1210   test_convert_to_integer_maybe_fold ();
1211 }
1212
1213 } // namespace selftest
1214
1215 #endif /* CHECKING_P */