Mercurial > hg > CbC > CbC_gcc
annotate gcc/convert.c @ 19:58ad6c70ea60
update gcc from 4.4.0 to 4.4.1.
| author | kent@firefly.cr.ie.u-ryukyu.ac.jp |
|---|---|
| date | Thu, 24 Sep 2009 13:21:57 +0900 |
| parents | a06113de4d67 |
| children | 77e2b8dfacca |
| rev | line source |
|---|---|
| 0 | 1 /* Utility routines for data type conversion for GCC. |
| 2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1997, 1998, | |
| 3 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 | |
| 4 Free Software Foundation, Inc. | |
| 5 | |
| 6 This file is part of GCC. | |
| 7 | |
| 8 GCC is free software; you can redistribute it and/or modify it under | |
| 9 the terms of the GNU General Public License as published by the Free | |
| 10 Software Foundation; either version 3, or (at your option) any later | |
| 11 version. | |
| 12 | |
| 13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
| 14 WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 16 for more details. | |
| 17 | |
| 18 You should have received a copy of the GNU General Public License | |
| 19 along with GCC; see the file COPYING3. If not see | |
| 20 <http://www.gnu.org/licenses/>. */ | |
| 21 | |
| 22 | |
| 23 /* These routines are somewhat language-independent utility function | |
| 24 intended to be called by the language-specific convert () functions. */ | |
| 25 | |
| 26 #include "config.h" | |
| 27 #include "system.h" | |
| 28 #include "coretypes.h" | |
| 29 #include "tm.h" | |
| 30 #include "tree.h" | |
| 31 #include "flags.h" | |
| 32 #include "convert.h" | |
| 33 #include "toplev.h" | |
| 34 #include "langhooks.h" | |
| 35 #include "real.h" | |
| 36 #include "fixed-value.h" | |
| 37 | |
| 38 /* Convert EXPR to some pointer or reference type TYPE. | |
| 39 EXPR must be pointer, reference, integer, enumeral, or literal zero; | |
| 40 in other cases error is called. */ | |
| 41 | |
| 42 tree | |
| 43 convert_to_pointer (tree type, tree expr) | |
| 44 { | |
| 45 if (TREE_TYPE (expr) == type) | |
| 46 return expr; | |
| 47 | |
| 48 /* Propagate overflow to the NULL pointer. */ | |
| 49 if (integer_zerop (expr)) | |
| 50 return force_fit_type_double (type, 0, 0, 0, TREE_OVERFLOW (expr)); | |
| 51 | |
| 52 switch (TREE_CODE (TREE_TYPE (expr))) | |
| 53 { | |
| 54 case POINTER_TYPE: | |
| 55 case REFERENCE_TYPE: | |
| 56 return fold_build1 (NOP_EXPR, type, expr); | |
| 57 | |
| 58 case INTEGER_TYPE: | |
| 59 case ENUMERAL_TYPE: | |
| 60 case BOOLEAN_TYPE: | |
| 61 if (TYPE_PRECISION (TREE_TYPE (expr)) != POINTER_SIZE) | |
| 62 expr = fold_build1 (NOP_EXPR, | |
| 63 lang_hooks.types.type_for_size (POINTER_SIZE, 0), | |
| 64 expr); | |
| 65 return fold_build1 (CONVERT_EXPR, type, expr); | |
| 66 | |
| 67 | |
| 68 default: | |
| 69 error ("cannot convert to a pointer type"); | |
| 70 return convert_to_pointer (type, integer_zero_node); | |
| 71 } | |
| 72 } | |
| 73 | |
| 74 /* Avoid any floating point extensions from EXP. */ | |
| 75 tree | |
| 76 strip_float_extensions (tree exp) | |
| 77 { | |
| 78 tree sub, expt, subt; | |
| 79 | |
| 80 /* For floating point constant look up the narrowest type that can hold | |
| 81 it properly and handle it like (type)(narrowest_type)constant. | |
| 82 This way we can optimize for instance a=a*2.0 where "a" is float | |
| 83 but 2.0 is double constant. */ | |
| 84 if (TREE_CODE (exp) == REAL_CST && !DECIMAL_FLOAT_TYPE_P (TREE_TYPE (exp))) | |
| 85 { | |
| 86 REAL_VALUE_TYPE orig; | |
| 87 tree type = NULL; | |
| 88 | |
| 89 orig = TREE_REAL_CST (exp); | |
| 90 if (TYPE_PRECISION (TREE_TYPE (exp)) > TYPE_PRECISION (float_type_node) | |
| 91 && exact_real_truncate (TYPE_MODE (float_type_node), &orig)) | |
| 92 type = float_type_node; | |
| 93 else if (TYPE_PRECISION (TREE_TYPE (exp)) | |
| 94 > TYPE_PRECISION (double_type_node) | |
| 95 && exact_real_truncate (TYPE_MODE (double_type_node), &orig)) | |
| 96 type = double_type_node; | |
| 97 if (type) | |
| 98 return build_real (type, real_value_truncate (TYPE_MODE (type), orig)); | |
| 99 } | |
| 100 | |
| 101 if (!CONVERT_EXPR_P (exp)) | |
| 102 return exp; | |
| 103 | |
| 104 sub = TREE_OPERAND (exp, 0); | |
| 105 subt = TREE_TYPE (sub); | |
| 106 expt = TREE_TYPE (exp); | |
| 107 | |
| 108 if (!FLOAT_TYPE_P (subt)) | |
| 109 return exp; | |
| 110 | |
| 111 if (DECIMAL_FLOAT_TYPE_P (expt) != DECIMAL_FLOAT_TYPE_P (subt)) | |
| 112 return exp; | |
| 113 | |
| 114 if (TYPE_PRECISION (subt) > TYPE_PRECISION (expt)) | |
| 115 return exp; | |
| 116 | |
| 117 return strip_float_extensions (sub); | |
| 118 } | |
| 119 | |
| 120 | |
| 121 /* Convert EXPR to some floating-point type TYPE. | |
| 122 | |
| 123 EXPR must be float, fixed-point, integer, or enumeral; | |
| 124 in other cases error is called. */ | |
| 125 | |
| 126 tree | |
| 127 convert_to_real (tree type, tree expr) | |
| 128 { | |
| 129 enum built_in_function fcode = builtin_mathfn_code (expr); | |
| 130 tree itype = TREE_TYPE (expr); | |
| 131 | |
| 132 /* Disable until we figure out how to decide whether the functions are | |
| 133 present in runtime. */ | |
| 134 /* Convert (float)sqrt((double)x) where x is float into sqrtf(x) */ | |
| 135 if (optimize | |
| 136 && (TYPE_MODE (type) == TYPE_MODE (double_type_node) | |
| 137 || TYPE_MODE (type) == TYPE_MODE (float_type_node))) | |
| 138 { | |
| 139 switch (fcode) | |
| 140 { | |
| 141 #define CASE_MATHFN(FN) case BUILT_IN_##FN: case BUILT_IN_##FN##L: | |
| 142 CASE_MATHFN (COSH) | |
| 143 CASE_MATHFN (EXP) | |
| 144 CASE_MATHFN (EXP10) | |
| 145 CASE_MATHFN (EXP2) | |
| 146 CASE_MATHFN (EXPM1) | |
| 147 CASE_MATHFN (GAMMA) | |
| 148 CASE_MATHFN (J0) | |
| 149 CASE_MATHFN (J1) | |
| 150 CASE_MATHFN (LGAMMA) | |
| 151 CASE_MATHFN (POW10) | |
| 152 CASE_MATHFN (SINH) | |
| 153 CASE_MATHFN (TGAMMA) | |
| 154 CASE_MATHFN (Y0) | |
| 155 CASE_MATHFN (Y1) | |
| 156 /* The above functions may set errno differently with float | |
| 157 input or output so this transformation is not safe with | |
| 158 -fmath-errno. */ | |
| 159 if (flag_errno_math) | |
| 160 break; | |
| 161 CASE_MATHFN (ACOS) | |
| 162 CASE_MATHFN (ACOSH) | |
| 163 CASE_MATHFN (ASIN) | |
| 164 CASE_MATHFN (ASINH) | |
| 165 CASE_MATHFN (ATAN) | |
| 166 CASE_MATHFN (ATANH) | |
| 167 CASE_MATHFN (CBRT) | |
| 168 CASE_MATHFN (COS) | |
| 169 CASE_MATHFN (ERF) | |
| 170 CASE_MATHFN (ERFC) | |
| 171 CASE_MATHFN (FABS) | |
| 172 CASE_MATHFN (LOG) | |
| 173 CASE_MATHFN (LOG10) | |
| 174 CASE_MATHFN (LOG2) | |
| 175 CASE_MATHFN (LOG1P) | |
| 176 CASE_MATHFN (LOGB) | |
| 177 CASE_MATHFN (SIN) | |
| 178 CASE_MATHFN (SQRT) | |
| 179 CASE_MATHFN (TAN) | |
| 180 CASE_MATHFN (TANH) | |
| 181 #undef CASE_MATHFN | |
| 182 { | |
| 183 tree arg0 = strip_float_extensions (CALL_EXPR_ARG (expr, 0)); | |
| 184 tree newtype = type; | |
| 185 | |
| 186 /* We have (outertype)sqrt((innertype)x). Choose the wider mode from | |
| 187 the both as the safe type for operation. */ | |
| 188 if (TYPE_PRECISION (TREE_TYPE (arg0)) > TYPE_PRECISION (type)) | |
| 189 newtype = TREE_TYPE (arg0); | |
| 190 | |
| 191 /* Be careful about integer to fp conversions. | |
| 192 These may overflow still. */ | |
| 193 if (FLOAT_TYPE_P (TREE_TYPE (arg0)) | |
| 194 && TYPE_PRECISION (newtype) < TYPE_PRECISION (itype) | |
| 195 && (TYPE_MODE (newtype) == TYPE_MODE (double_type_node) | |
| 196 || TYPE_MODE (newtype) == TYPE_MODE (float_type_node))) | |
| 197 { | |
| 198 tree fn = mathfn_built_in (newtype, fcode); | |
| 199 | |
| 200 if (fn) | |
| 201 { | |
| 202 tree arg = fold (convert_to_real (newtype, arg0)); | |
| 203 expr = build_call_expr (fn, 1, arg); | |
| 204 if (newtype == type) | |
| 205 return expr; | |
| 206 } | |
| 207 } | |
| 208 } | |
| 209 default: | |
| 210 break; | |
| 211 } | |
| 212 } | |
| 213 if (optimize | |
| 214 && (((fcode == BUILT_IN_FLOORL | |
| 215 || fcode == BUILT_IN_CEILL | |
| 216 || fcode == BUILT_IN_ROUNDL | |
| 217 || fcode == BUILT_IN_RINTL | |
| 218 || fcode == BUILT_IN_TRUNCL | |
| 219 || fcode == BUILT_IN_NEARBYINTL) | |
| 220 && (TYPE_MODE (type) == TYPE_MODE (double_type_node) | |
| 221 || TYPE_MODE (type) == TYPE_MODE (float_type_node))) | |
| 222 || ((fcode == BUILT_IN_FLOOR | |
| 223 || fcode == BUILT_IN_CEIL | |
| 224 || fcode == BUILT_IN_ROUND | |
| 225 || fcode == BUILT_IN_RINT | |
| 226 || fcode == BUILT_IN_TRUNC | |
| 227 || fcode == BUILT_IN_NEARBYINT) | |
| 228 && (TYPE_MODE (type) == TYPE_MODE (float_type_node))))) | |
| 229 { | |
| 230 tree fn = mathfn_built_in (type, fcode); | |
| 231 | |
| 232 if (fn) | |
| 233 { | |
| 234 tree arg = strip_float_extensions (CALL_EXPR_ARG (expr, 0)); | |
| 235 | |
| 236 /* Make sure (type)arg0 is an extension, otherwise we could end up | |
| 237 changing (float)floor(double d) into floorf((float)d), which is | |
| 238 incorrect because (float)d uses round-to-nearest and can round | |
| 239 up to the next integer. */ | |
| 240 if (TYPE_PRECISION (type) >= TYPE_PRECISION (TREE_TYPE (arg))) | |
| 241 return build_call_expr (fn, 1, fold (convert_to_real (type, arg))); | |
| 242 } | |
| 243 } | |
| 244 | |
| 245 /* Propagate the cast into the operation. */ | |
| 246 if (itype != type && FLOAT_TYPE_P (type)) | |
| 247 switch (TREE_CODE (expr)) | |
| 248 { | |
| 249 /* Convert (float)-x into -(float)x. This is safe for | |
| 250 round-to-nearest rounding mode. */ | |
| 251 case ABS_EXPR: | |
| 252 case NEGATE_EXPR: | |
| 253 if (!flag_rounding_math | |
| 254 && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (expr))) | |
| 255 return build1 (TREE_CODE (expr), type, | |
| 256 fold (convert_to_real (type, | |
| 257 TREE_OPERAND (expr, 0)))); | |
| 258 break; | |
| 259 /* Convert (outertype)((innertype0)a+(innertype1)b) | |
| 260 into ((newtype)a+(newtype)b) where newtype | |
| 261 is the widest mode from all of these. */ | |
| 262 case PLUS_EXPR: | |
| 263 case MINUS_EXPR: | |
| 264 case MULT_EXPR: | |
| 265 case RDIV_EXPR: | |
| 266 { | |
| 267 tree arg0 = strip_float_extensions (TREE_OPERAND (expr, 0)); | |
| 268 tree arg1 = strip_float_extensions (TREE_OPERAND (expr, 1)); | |
| 269 | |
| 270 if (FLOAT_TYPE_P (TREE_TYPE (arg0)) | |
| 271 && FLOAT_TYPE_P (TREE_TYPE (arg1)) | |
| 272 && DECIMAL_FLOAT_TYPE_P (itype) == DECIMAL_FLOAT_TYPE_P (type)) | |
| 273 { | |
| 274 tree newtype = type; | |
| 275 | |
| 276 if (TYPE_MODE (TREE_TYPE (arg0)) == SDmode | |
| 277 || TYPE_MODE (TREE_TYPE (arg1)) == SDmode | |
| 278 || TYPE_MODE (type) == SDmode) | |
| 279 newtype = dfloat32_type_node; | |
| 280 if (TYPE_MODE (TREE_TYPE (arg0)) == DDmode | |
| 281 || TYPE_MODE (TREE_TYPE (arg1)) == DDmode | |
| 282 || TYPE_MODE (type) == DDmode) | |
| 283 newtype = dfloat64_type_node; | |
| 284 if (TYPE_MODE (TREE_TYPE (arg0)) == TDmode | |
| 285 || TYPE_MODE (TREE_TYPE (arg1)) == TDmode | |
| 286 || TYPE_MODE (type) == TDmode) | |
| 287 newtype = dfloat128_type_node; | |
| 288 if (newtype == dfloat32_type_node | |
| 289 || newtype == dfloat64_type_node | |
| 290 || newtype == dfloat128_type_node) | |
| 291 { | |
| 292 expr = build2 (TREE_CODE (expr), newtype, | |
| 293 fold (convert_to_real (newtype, arg0)), | |
| 294 fold (convert_to_real (newtype, arg1))); | |
| 295 if (newtype == type) | |
| 296 return expr; | |
| 297 break; | |
| 298 } | |
| 299 | |
| 300 if (TYPE_PRECISION (TREE_TYPE (arg0)) > TYPE_PRECISION (newtype)) | |
| 301 newtype = TREE_TYPE (arg0); | |
| 302 if (TYPE_PRECISION (TREE_TYPE (arg1)) > TYPE_PRECISION (newtype)) | |
| 303 newtype = TREE_TYPE (arg1); | |
| 304 /* Sometimes this transformation is safe (cannot | |
| 305 change results through affecting double rounding | |
| 306 cases) and sometimes it is not. If NEWTYPE is | |
| 307 wider than TYPE, e.g. (float)((long double)double | |
| 308 + (long double)double) converted to | |
| 309 (float)(double + double), the transformation is | |
| 310 unsafe regardless of the details of the types | |
| 311 involved; double rounding can arise if the result | |
| 312 of NEWTYPE arithmetic is a NEWTYPE value half way | |
| 313 between two representable TYPE values but the | |
| 314 exact value is sufficiently different (in the | |
| 315 right direction) for this difference to be | |
| 316 visible in ITYPE arithmetic. If NEWTYPE is the | |
| 317 same as TYPE, however, the transformation may be | |
| 318 safe depending on the types involved: it is safe | |
| 319 if the ITYPE has strictly more than twice as many | |
| 320 mantissa bits as TYPE, can represent infinities | |
| 321 and NaNs if the TYPE can, and has sufficient | |
| 322 exponent range for the product or ratio of two | |
| 323 values representable in the TYPE to be within the | |
| 324 range of normal values of ITYPE. */ | |
| 325 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (itype) | |
| 326 && (flag_unsafe_math_optimizations | |
| 327 || (TYPE_PRECISION (newtype) == TYPE_PRECISION (type) | |
| 328 && real_can_shorten_arithmetic (TYPE_MODE (itype), | |
| 329 TYPE_MODE (type))))) | |
| 330 { | |
| 331 expr = build2 (TREE_CODE (expr), newtype, | |
| 332 fold (convert_to_real (newtype, arg0)), | |
| 333 fold (convert_to_real (newtype, arg1))); | |
| 334 if (newtype == type) | |
| 335 return expr; | |
| 336 } | |
| 337 } | |
| 338 } | |
| 339 break; | |
| 340 default: | |
| 341 break; | |
| 342 } | |
| 343 | |
| 344 switch (TREE_CODE (TREE_TYPE (expr))) | |
| 345 { | |
| 346 case REAL_TYPE: | |
| 347 /* Ignore the conversion if we don't need to store intermediate | |
| 348 results and neither type is a decimal float. */ | |
| 349 return build1 ((flag_float_store | |
| 350 || DECIMAL_FLOAT_TYPE_P (type) | |
| 351 || DECIMAL_FLOAT_TYPE_P (itype)) | |
| 352 ? CONVERT_EXPR : NOP_EXPR, type, expr); | |
| 353 | |
| 354 case INTEGER_TYPE: | |
| 355 case ENUMERAL_TYPE: | |
| 356 case BOOLEAN_TYPE: | |
| 357 return build1 (FLOAT_EXPR, type, expr); | |
| 358 | |
| 359 case FIXED_POINT_TYPE: | |
| 360 return build1 (FIXED_CONVERT_EXPR, type, expr); | |
| 361 | |
| 362 case COMPLEX_TYPE: | |
| 363 return convert (type, | |
| 364 fold_build1 (REALPART_EXPR, | |
| 365 TREE_TYPE (TREE_TYPE (expr)), expr)); | |
| 366 | |
| 367 case POINTER_TYPE: | |
| 368 case REFERENCE_TYPE: | |
| 369 error ("pointer value used where a floating point value was expected"); | |
| 370 return convert_to_real (type, integer_zero_node); | |
| 371 | |
| 372 default: | |
| 373 error ("aggregate value used where a float was expected"); | |
| 374 return convert_to_real (type, integer_zero_node); | |
| 375 } | |
| 376 } | |
| 377 | |
| 378 /* Convert EXPR to some integer (or enum) type TYPE. | |
| 379 | |
| 380 EXPR must be pointer, integer, discrete (enum, char, or bool), float, | |
| 381 fixed-point or vector; in other cases error is called. | |
| 382 | |
| 383 The result of this is always supposed to be a newly created tree node | |
| 384 not in use in any existing structure. */ | |
| 385 | |
| 386 tree | |
| 387 convert_to_integer (tree type, tree expr) | |
| 388 { | |
| 389 enum tree_code ex_form = TREE_CODE (expr); | |
| 390 tree intype = TREE_TYPE (expr); | |
| 391 unsigned int inprec = TYPE_PRECISION (intype); | |
| 392 unsigned int outprec = TYPE_PRECISION (type); | |
| 393 | |
| 394 /* An INTEGER_TYPE cannot be incomplete, but an ENUMERAL_TYPE can | |
| 395 be. Consider `enum E = { a, b = (enum E) 3 };'. */ | |
| 396 if (!COMPLETE_TYPE_P (type)) | |
| 397 { | |
| 398 error ("conversion to incomplete type"); | |
| 399 return error_mark_node; | |
| 400 } | |
| 401 | |
| 402 /* Convert e.g. (long)round(d) -> lround(d). */ | |
| 403 /* If we're converting to char, we may encounter differing behavior | |
| 404 between converting from double->char vs double->long->char. | |
| 405 We're in "undefined" territory but we prefer to be conservative, | |
| 406 so only proceed in "unsafe" math mode. */ | |
| 407 if (optimize | |
| 408 && (flag_unsafe_math_optimizations | |
| 409 || (long_integer_type_node | |
| 410 && outprec >= TYPE_PRECISION (long_integer_type_node)))) | |
| 411 { | |
| 412 tree s_expr = strip_float_extensions (expr); | |
| 413 tree s_intype = TREE_TYPE (s_expr); | |
| 414 const enum built_in_function fcode = builtin_mathfn_code (s_expr); | |
| 415 tree fn = 0; | |
| 416 | |
| 417 switch (fcode) | |
| 418 { | |
| 419 CASE_FLT_FN (BUILT_IN_CEIL): | |
| 420 /* Only convert in ISO C99 mode. */ | |
| 421 if (!TARGET_C99_FUNCTIONS) | |
| 422 break; | |
| 423 if (outprec < TYPE_PRECISION (long_integer_type_node) | |
| 424 || (outprec == TYPE_PRECISION (long_integer_type_node) | |
| 425 && !TYPE_UNSIGNED (type))) | |
| 426 fn = mathfn_built_in (s_intype, BUILT_IN_LCEIL); | |
| 427 else if (outprec == TYPE_PRECISION (long_long_integer_type_node) | |
| 428 && !TYPE_UNSIGNED (type)) | |
| 429 fn = mathfn_built_in (s_intype, BUILT_IN_LLCEIL); | |
| 430 break; | |
| 431 | |
| 432 CASE_FLT_FN (BUILT_IN_FLOOR): | |
| 433 /* Only convert in ISO C99 mode. */ | |
| 434 if (!TARGET_C99_FUNCTIONS) | |
| 435 break; | |
| 436 if (outprec < TYPE_PRECISION (long_integer_type_node) | |
| 437 || (outprec == TYPE_PRECISION (long_integer_type_node) | |
| 438 && !TYPE_UNSIGNED (type))) | |
| 439 fn = mathfn_built_in (s_intype, BUILT_IN_LFLOOR); | |
| 440 else if (outprec == TYPE_PRECISION (long_long_integer_type_node) | |
| 441 && !TYPE_UNSIGNED (type)) | |
| 442 fn = mathfn_built_in (s_intype, BUILT_IN_LLFLOOR); | |
| 443 break; | |
| 444 | |
| 445 CASE_FLT_FN (BUILT_IN_ROUND): | |
| 446 if (outprec < TYPE_PRECISION (long_integer_type_node) | |
| 447 || (outprec == TYPE_PRECISION (long_integer_type_node) | |
| 448 && !TYPE_UNSIGNED (type))) | |
| 449 fn = mathfn_built_in (s_intype, BUILT_IN_LROUND); | |
| 450 else if (outprec == TYPE_PRECISION (long_long_integer_type_node) | |
| 451 && !TYPE_UNSIGNED (type)) | |
| 452 fn = mathfn_built_in (s_intype, BUILT_IN_LLROUND); | |
| 453 break; | |
| 454 | |
| 455 CASE_FLT_FN (BUILT_IN_NEARBYINT): | |
| 456 /* Only convert nearbyint* if we can ignore math exceptions. */ | |
| 457 if (flag_trapping_math) | |
| 458 break; | |
| 459 /* ... Fall through ... */ | |
| 460 CASE_FLT_FN (BUILT_IN_RINT): | |
| 461 if (outprec < TYPE_PRECISION (long_integer_type_node) | |
| 462 || (outprec == TYPE_PRECISION (long_integer_type_node) | |
| 463 && !TYPE_UNSIGNED (type))) | |
| 464 fn = mathfn_built_in (s_intype, BUILT_IN_LRINT); | |
| 465 else if (outprec == TYPE_PRECISION (long_long_integer_type_node) | |
| 466 && !TYPE_UNSIGNED (type)) | |
| 467 fn = mathfn_built_in (s_intype, BUILT_IN_LLRINT); | |
| 468 break; | |
| 469 | |
| 470 CASE_FLT_FN (BUILT_IN_TRUNC): | |
| 471 return convert_to_integer (type, CALL_EXPR_ARG (s_expr, 0)); | |
| 472 | |
| 473 default: | |
| 474 break; | |
| 475 } | |
| 476 | |
| 477 if (fn) | |
| 478 { | |
| 479 tree newexpr = build_call_expr (fn, 1, CALL_EXPR_ARG (s_expr, 0)); | |
| 480 return convert_to_integer (type, newexpr); | |
| 481 } | |
| 482 } | |
| 483 | |
| 484 switch (TREE_CODE (intype)) | |
| 485 { | |
| 486 case POINTER_TYPE: | |
| 487 case REFERENCE_TYPE: | |
| 488 if (integer_zerop (expr)) | |
| 489 return build_int_cst (type, 0); | |
| 490 | |
| 491 /* Convert to an unsigned integer of the correct width first, | |
| 492 and from there widen/truncate to the required type. */ | |
| 493 expr = fold_build1 (CONVERT_EXPR, | |
| 494 lang_hooks.types.type_for_size (POINTER_SIZE, 0), | |
| 495 expr); | |
| 496 return fold_convert (type, expr); | |
| 497 | |
| 498 case INTEGER_TYPE: | |
| 499 case ENUMERAL_TYPE: | |
| 500 case BOOLEAN_TYPE: | |
| 501 case OFFSET_TYPE: | |
| 502 /* If this is a logical operation, which just returns 0 or 1, we can | |
| 503 change the type of the expression. */ | |
| 504 | |
| 505 if (TREE_CODE_CLASS (ex_form) == tcc_comparison) | |
| 506 { | |
| 507 expr = copy_node (expr); | |
| 508 TREE_TYPE (expr) = type; | |
| 509 return expr; | |
| 510 } | |
| 511 | |
| 512 /* If we are widening the type, put in an explicit conversion. | |
| 513 Similarly if we are not changing the width. After this, we know | |
| 514 we are truncating EXPR. */ | |
| 515 | |
| 516 else if (outprec >= inprec) | |
| 517 { | |
| 518 enum tree_code code; | |
| 519 tree tem; | |
| 520 | |
| 521 /* If the precision of the EXPR's type is K bits and the | |
| 522 destination mode has more bits, and the sign is changing, | |
| 523 it is not safe to use a NOP_EXPR. For example, suppose | |
| 524 that EXPR's type is a 3-bit unsigned integer type, the | |
| 525 TYPE is a 3-bit signed integer type, and the machine mode | |
| 526 for the types is 8-bit QImode. In that case, the | |
| 527 conversion necessitates an explicit sign-extension. In | |
| 528 the signed-to-unsigned case the high-order bits have to | |
| 529 be cleared. */ | |
| 530 if (TYPE_UNSIGNED (type) != TYPE_UNSIGNED (TREE_TYPE (expr)) | |
| 531 && (TYPE_PRECISION (TREE_TYPE (expr)) | |
| 532 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr))))) | |
| 533 code = CONVERT_EXPR; | |
| 534 else | |
| 535 code = NOP_EXPR; | |
| 536 | |
| 537 tem = fold_unary (code, type, expr); | |
| 538 if (tem) | |
| 539 return tem; | |
| 540 | |
| 541 tem = build1 (code, type, expr); | |
| 542 TREE_NO_WARNING (tem) = 1; | |
| 543 return tem; | |
| 544 } | |
| 545 | |
| 546 /* If TYPE is an enumeral type or a type with a precision less | |
| 547 than the number of bits in its mode, do the conversion to the | |
| 548 type corresponding to its mode, then do a nop conversion | |
| 549 to TYPE. */ | |
| 550 else if (TREE_CODE (type) == ENUMERAL_TYPE | |
| 551 || outprec != GET_MODE_BITSIZE (TYPE_MODE (type))) | |
| 552 return build1 (NOP_EXPR, type, | |
| 553 convert (lang_hooks.types.type_for_mode | |
| 554 (TYPE_MODE (type), TYPE_UNSIGNED (type)), | |
| 555 expr)); | |
| 556 | |
| 557 /* Here detect when we can distribute the truncation down past some | |
| 558 arithmetic. For example, if adding two longs and converting to an | |
| 559 int, we can equally well convert both to ints and then add. | |
| 560 For the operations handled here, such truncation distribution | |
| 561 is always safe. | |
| 562 It is desirable in these cases: | |
| 563 1) when truncating down to full-word from a larger size | |
| 564 2) when truncating takes no work. | |
| 565 3) when at least one operand of the arithmetic has been extended | |
| 566 (as by C's default conversions). In this case we need two conversions | |
| 567 if we do the arithmetic as already requested, so we might as well | |
| 568 truncate both and then combine. Perhaps that way we need only one. | |
| 569 | |
| 570 Note that in general we cannot do the arithmetic in a type | |
| 571 shorter than the desired result of conversion, even if the operands | |
| 572 are both extended from a shorter type, because they might overflow | |
| 573 if combined in that type. The exceptions to this--the times when | |
| 574 two narrow values can be combined in their narrow type even to | |
| 575 make a wider result--are handled by "shorten" in build_binary_op. */ | |
| 576 | |
| 577 switch (ex_form) | |
| 578 { | |
| 579 case RSHIFT_EXPR: | |
| 580 /* We can pass truncation down through right shifting | |
| 581 when the shift count is a nonpositive constant. */ | |
| 582 if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST | |
| 583 && tree_int_cst_sgn (TREE_OPERAND (expr, 1)) <= 0) | |
| 584 goto trunc1; | |
| 585 break; | |
| 586 | |
| 587 case LSHIFT_EXPR: | |
| 588 /* We can pass truncation down through left shifting | |
| 589 when the shift count is a nonnegative constant and | |
| 590 the target type is unsigned. */ | |
| 591 if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST | |
| 592 && tree_int_cst_sgn (TREE_OPERAND (expr, 1)) >= 0 | |
| 593 && TYPE_UNSIGNED (type) | |
| 594 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST) | |
| 595 { | |
| 596 /* If shift count is less than the width of the truncated type, | |
| 597 really shift. */ | |
| 598 if (tree_int_cst_lt (TREE_OPERAND (expr, 1), TYPE_SIZE (type))) | |
| 599 /* In this case, shifting is like multiplication. */ | |
| 600 goto trunc1; | |
| 601 else | |
| 602 { | |
| 603 /* If it is >= that width, result is zero. | |
| 604 Handling this with trunc1 would give the wrong result: | |
| 605 (int) ((long long) a << 32) is well defined (as 0) | |
| 606 but (int) a << 32 is undefined and would get a | |
| 607 warning. */ | |
| 608 | |
| 609 tree t = build_int_cst (type, 0); | |
| 610 | |
| 611 /* If the original expression had side-effects, we must | |
| 612 preserve it. */ | |
| 613 if (TREE_SIDE_EFFECTS (expr)) | |
| 614 return build2 (COMPOUND_EXPR, type, expr, t); | |
| 615 else | |
| 616 return t; | |
| 617 } | |
| 618 } | |
| 619 break; | |
| 620 | |
| 621 case MAX_EXPR: | |
| 622 case MIN_EXPR: | |
| 623 case MULT_EXPR: | |
| 624 { | |
| 625 tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type); | |
| 626 tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type); | |
| 627 | |
| 628 /* Don't distribute unless the output precision is at least as big | |
| 629 as the actual inputs. Otherwise, the comparison of the | |
| 630 truncated values will be wrong. */ | |
| 631 if (outprec >= TYPE_PRECISION (TREE_TYPE (arg0)) | |
| 632 && outprec >= TYPE_PRECISION (TREE_TYPE (arg1)) | |
| 633 /* If signedness of arg0 and arg1 don't match, | |
| 634 we can't necessarily find a type to compare them in. */ | |
| 635 && (TYPE_UNSIGNED (TREE_TYPE (arg0)) | |
| 636 == TYPE_UNSIGNED (TREE_TYPE (arg1)))) | |
| 637 goto trunc1; | |
| 638 break; | |
| 639 } | |
| 640 | |
| 641 case PLUS_EXPR: | |
| 642 case MINUS_EXPR: | |
| 643 case BIT_AND_EXPR: | |
| 644 case BIT_IOR_EXPR: | |
| 645 case BIT_XOR_EXPR: | |
| 646 trunc1: | |
| 647 { | |
| 648 tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type); | |
| 649 tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type); | |
| 650 | |
| 651 if (outprec >= BITS_PER_WORD | |
| 652 || TRULY_NOOP_TRUNCATION (outprec, inprec) | |
| 653 || inprec > TYPE_PRECISION (TREE_TYPE (arg0)) | |
| 654 || inprec > TYPE_PRECISION (TREE_TYPE (arg1))) | |
| 655 { | |
| 656 /* Do the arithmetic in type TYPEX, | |
| 657 then convert result to TYPE. */ | |
| 658 tree typex = type; | |
| 659 | |
| 660 /* Can't do arithmetic in enumeral types | |
| 661 so use an integer type that will hold the values. */ | |
| 662 if (TREE_CODE (typex) == ENUMERAL_TYPE) | |
| 663 typex = lang_hooks.types.type_for_size | |
| 664 (TYPE_PRECISION (typex), TYPE_UNSIGNED (typex)); | |
| 665 | |
| 666 /* But now perhaps TYPEX is as wide as INPREC. | |
| 667 In that case, do nothing special here. | |
| 668 (Otherwise would recurse infinitely in convert. */ | |
| 669 if (TYPE_PRECISION (typex) != inprec) | |
| 670 { | |
| 671 /* Don't do unsigned arithmetic where signed was wanted, | |
| 672 or vice versa. | |
| 673 Exception: if both of the original operands were | |
| 674 unsigned then we can safely do the work as unsigned. | |
| 675 Exception: shift operations take their type solely | |
| 676 from the first argument. | |
| 677 Exception: the LSHIFT_EXPR case above requires that | |
| 678 we perform this operation unsigned lest we produce | |
| 679 signed-overflow undefinedness. | |
| 680 And we may need to do it as unsigned | |
| 681 if we truncate to the original size. */ | |
| 682 if (TYPE_UNSIGNED (TREE_TYPE (expr)) | |
| 683 || (TYPE_UNSIGNED (TREE_TYPE (arg0)) | |
| 684 && (TYPE_UNSIGNED (TREE_TYPE (arg1)) | |
| 685 || ex_form == LSHIFT_EXPR | |
| 686 || ex_form == RSHIFT_EXPR | |
| 687 || ex_form == LROTATE_EXPR | |
| 688 || ex_form == RROTATE_EXPR)) | |
| 689 || ex_form == LSHIFT_EXPR | |
| 690 /* If we have !flag_wrapv, and either ARG0 or | |
| 691 ARG1 is of a signed type, we have to do | |
| 692 PLUS_EXPR or MINUS_EXPR in an unsigned | |
| 693 type. Otherwise, we would introduce | |
| 694 signed-overflow undefinedness. */ | |
| 695 || ((!TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0)) | |
| 696 || !TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg1))) | |
| 697 && (ex_form == PLUS_EXPR | |
| 698 || ex_form == MINUS_EXPR))) | |
| 699 typex = unsigned_type_for (typex); | |
| 700 else | |
| 701 typex = signed_type_for (typex); | |
| 702 return convert (type, | |
| 703 fold_build2 (ex_form, typex, | |
| 704 convert (typex, arg0), | |
| 705 convert (typex, arg1))); | |
| 706 } | |
| 707 } | |
| 708 } | |
| 709 break; | |
| 710 | |
| 711 case NEGATE_EXPR: | |
| 712 case BIT_NOT_EXPR: | |
| 713 /* This is not correct for ABS_EXPR, | |
| 714 since we must test the sign before truncation. */ | |
| 715 { | |
| 716 tree typex; | |
| 717 | |
| 718 /* Don't do unsigned arithmetic where signed was wanted, | |
| 719 or vice versa. */ | |
| 720 if (TYPE_UNSIGNED (TREE_TYPE (expr))) | |
| 721 typex = unsigned_type_for (type); | |
| 722 else | |
| 723 typex = signed_type_for (type); | |
| 724 return convert (type, | |
| 725 fold_build1 (ex_form, typex, | |
| 726 convert (typex, | |
| 727 TREE_OPERAND (expr, 0)))); | |
| 728 } | |
| 729 | |
| 730 case NOP_EXPR: | |
| 731 /* Don't introduce a | |
| 732 "can't convert between vector values of different size" error. */ | |
| 733 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == VECTOR_TYPE | |
| 734 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_OPERAND (expr, 0)))) | |
| 735 != GET_MODE_SIZE (TYPE_MODE (type)))) | |
| 736 break; | |
| 737 /* If truncating after truncating, might as well do all at once. | |
| 738 If truncating after extending, we may get rid of wasted work. */ | |
| 739 return convert (type, get_unwidened (TREE_OPERAND (expr, 0), type)); | |
| 740 | |
| 741 case COND_EXPR: | |
| 742 /* It is sometimes worthwhile to push the narrowing down through | |
|
19
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update gcc from 4.4.0 to 4.4.1.
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diff
changeset
|
743 the conditional and never loses. A COND_EXPR may have a throw |
|
58ad6c70ea60
update gcc from 4.4.0 to 4.4.1.
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parents:
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diff
changeset
|
744 as one operand, which then has void type. Just leave void |
|
58ad6c70ea60
update gcc from 4.4.0 to 4.4.1.
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parents:
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diff
changeset
|
745 operands as they are. */ |
| 0 | 746 return fold_build3 (COND_EXPR, type, TREE_OPERAND (expr, 0), |
|
19
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update gcc from 4.4.0 to 4.4.1.
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parents:
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diff
changeset
|
747 VOID_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 1))) |
|
58ad6c70ea60
update gcc from 4.4.0 to 4.4.1.
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parents:
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diff
changeset
|
748 ? TREE_OPERAND (expr, 1) |
|
58ad6c70ea60
update gcc from 4.4.0 to 4.4.1.
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parents:
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diff
changeset
|
749 : convert (type, TREE_OPERAND (expr, 1)), |
|
58ad6c70ea60
update gcc from 4.4.0 to 4.4.1.
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parents:
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diff
changeset
|
750 VOID_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 2))) |
|
58ad6c70ea60
update gcc from 4.4.0 to 4.4.1.
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parents:
0
diff
changeset
|
751 ? TREE_OPERAND (expr, 2) |
|
58ad6c70ea60
update gcc from 4.4.0 to 4.4.1.
kent@firefly.cr.ie.u-ryukyu.ac.jp
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diff
changeset
|
752 : convert (type, TREE_OPERAND (expr, 2))); |
| 0 | 753 |
| 754 default: | |
| 755 break; | |
| 756 } | |
| 757 | |
| 758 return build1 (CONVERT_EXPR, type, expr); | |
| 759 | |
| 760 case REAL_TYPE: | |
| 761 return build1 (FIX_TRUNC_EXPR, type, expr); | |
| 762 | |
| 763 case FIXED_POINT_TYPE: | |
| 764 return build1 (FIXED_CONVERT_EXPR, type, expr); | |
| 765 | |
| 766 case COMPLEX_TYPE: | |
| 767 return convert (type, | |
| 768 fold_build1 (REALPART_EXPR, | |
| 769 TREE_TYPE (TREE_TYPE (expr)), expr)); | |
| 770 | |
| 771 case VECTOR_TYPE: | |
| 772 if (!tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (TREE_TYPE (expr)))) | |
| 773 { | |
| 774 error ("can't convert between vector values of different size"); | |
| 775 return error_mark_node; | |
| 776 } | |
| 777 return build1 (VIEW_CONVERT_EXPR, type, expr); | |
| 778 | |
| 779 default: | |
| 780 error ("aggregate value used where an integer was expected"); | |
| 781 return convert (type, integer_zero_node); | |
| 782 } | |
| 783 } | |
| 784 | |
| 785 /* Convert EXPR to the complex type TYPE in the usual ways. */ | |
| 786 | |
| 787 tree | |
| 788 convert_to_complex (tree type, tree expr) | |
| 789 { | |
| 790 tree subtype = TREE_TYPE (type); | |
| 791 | |
| 792 switch (TREE_CODE (TREE_TYPE (expr))) | |
| 793 { | |
| 794 case REAL_TYPE: | |
| 795 case FIXED_POINT_TYPE: | |
| 796 case INTEGER_TYPE: | |
| 797 case ENUMERAL_TYPE: | |
| 798 case BOOLEAN_TYPE: | |
| 799 return build2 (COMPLEX_EXPR, type, convert (subtype, expr), | |
| 800 convert (subtype, integer_zero_node)); | |
| 801 | |
| 802 case COMPLEX_TYPE: | |
| 803 { | |
| 804 tree elt_type = TREE_TYPE (TREE_TYPE (expr)); | |
| 805 | |
| 806 if (TYPE_MAIN_VARIANT (elt_type) == TYPE_MAIN_VARIANT (subtype)) | |
| 807 return expr; | |
| 808 else if (TREE_CODE (expr) == COMPLEX_EXPR) | |
| 809 return fold_build2 (COMPLEX_EXPR, type, | |
| 810 convert (subtype, TREE_OPERAND (expr, 0)), | |
| 811 convert (subtype, TREE_OPERAND (expr, 1))); | |
| 812 else | |
| 813 { | |
| 814 expr = save_expr (expr); | |
| 815 return | |
| 816 fold_build2 (COMPLEX_EXPR, type, | |
| 817 convert (subtype, | |
| 818 fold_build1 (REALPART_EXPR, | |
| 819 TREE_TYPE (TREE_TYPE (expr)), | |
| 820 expr)), | |
| 821 convert (subtype, | |
| 822 fold_build1 (IMAGPART_EXPR, | |
| 823 TREE_TYPE (TREE_TYPE (expr)), | |
| 824 expr))); | |
| 825 } | |
| 826 } | |
| 827 | |
| 828 case POINTER_TYPE: | |
| 829 case REFERENCE_TYPE: | |
| 830 error ("pointer value used where a complex was expected"); | |
| 831 return convert_to_complex (type, integer_zero_node); | |
| 832 | |
| 833 default: | |
| 834 error ("aggregate value used where a complex was expected"); | |
| 835 return convert_to_complex (type, integer_zero_node); | |
| 836 } | |
| 837 } | |
| 838 | |
| 839 /* Convert EXPR to the vector type TYPE in the usual ways. */ | |
| 840 | |
| 841 tree | |
| 842 convert_to_vector (tree type, tree expr) | |
| 843 { | |
| 844 switch (TREE_CODE (TREE_TYPE (expr))) | |
| 845 { | |
| 846 case INTEGER_TYPE: | |
| 847 case VECTOR_TYPE: | |
| 848 if (!tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (TREE_TYPE (expr)))) | |
| 849 { | |
| 850 error ("can't convert between vector values of different size"); | |
| 851 return error_mark_node; | |
| 852 } | |
| 853 return build1 (VIEW_CONVERT_EXPR, type, expr); | |
| 854 | |
| 855 default: | |
| 856 error ("can't convert value to a vector"); | |
| 857 return error_mark_node; | |
| 858 } | |
| 859 } | |
| 860 | |
| 861 /* Convert EXPR to some fixed-point type TYPE. | |
| 862 | |
| 863 EXPR must be fixed-point, float, integer, or enumeral; | |
| 864 in other cases error is called. */ | |
| 865 | |
| 866 tree | |
| 867 convert_to_fixed (tree type, tree expr) | |
| 868 { | |
| 869 if (integer_zerop (expr)) | |
| 870 { | |
| 871 tree fixed_zero_node = build_fixed (type, FCONST0 (TYPE_MODE (type))); | |
| 872 return fixed_zero_node; | |
| 873 } | |
| 874 else if (integer_onep (expr) && ALL_SCALAR_ACCUM_MODE_P (TYPE_MODE (type))) | |
| 875 { | |
| 876 tree fixed_one_node = build_fixed (type, FCONST1 (TYPE_MODE (type))); | |
| 877 return fixed_one_node; | |
| 878 } | |
| 879 | |
| 880 switch (TREE_CODE (TREE_TYPE (expr))) | |
| 881 { | |
| 882 case FIXED_POINT_TYPE: | |
| 883 case INTEGER_TYPE: | |
| 884 case ENUMERAL_TYPE: | |
| 885 case BOOLEAN_TYPE: | |
| 886 case REAL_TYPE: | |
| 887 return build1 (FIXED_CONVERT_EXPR, type, expr); | |
| 888 | |
| 889 case COMPLEX_TYPE: | |
| 890 return convert (type, | |
| 891 fold_build1 (REALPART_EXPR, | |
| 892 TREE_TYPE (TREE_TYPE (expr)), expr)); | |
| 893 | |
| 894 default: | |
| 895 error ("aggregate value used where a fixed-point was expected"); | |
| 896 return error_mark_node; | |
| 897 } | |
| 898 } |