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5e6908ea | 1 | /* Utility routines for data type conversion for GCC. |
78bd5210 | 2 | Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1997, 1998, |
c8d3e15a | 3 | 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc. |
76e616db | 4 | |
1322177d | 5 | This file is part of GCC. |
76e616db | 6 | |
1322177d LB |
7 | GCC is free software; you can redistribute it and/or modify it under |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 2, or (at your option) any later | |
10 | version. | |
76e616db | 11 | |
1322177d LB |
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
76e616db BK |
16 | |
17 | You should have received a copy of the GNU General Public License | |
1322177d LB |
18 | along with GCC; see the file COPYING. If not, write to the Free |
19 | Software Foundation, 59 Temple Place - Suite 330, Boston, MA | |
20 | 02111-1307, USA. */ | |
76e616db BK |
21 | |
22 | ||
23 | /* These routines are somewhat language-independent utility function | |
0f41302f | 24 | intended to be called by the language-specific convert () functions. */ |
76e616db BK |
25 | |
26 | #include "config.h" | |
c5c76735 | 27 | #include "system.h" |
4977bab6 ZW |
28 | #include "coretypes.h" |
29 | #include "tm.h" | |
76e616db BK |
30 | #include "tree.h" |
31 | #include "flags.h" | |
32 | #include "convert.h" | |
10f0ad3d | 33 | #include "toplev.h" |
b0c48229 | 34 | #include "langhooks.h" |
77f9af81 | 35 | #include "real.h" |
98c76e3c | 36 | /* Convert EXPR to some pointer or reference type TYPE. |
76e616db | 37 | |
98c76e3c | 38 | EXPR must be pointer, reference, integer, enumeral, or literal zero; |
0f41302f | 39 | in other cases error is called. */ |
76e616db BK |
40 | |
41 | tree | |
159b3be1 | 42 | convert_to_pointer (tree type, tree expr) |
76e616db | 43 | { |
76e616db BK |
44 | if (integer_zerop (expr)) |
45 | { | |
7d60be94 | 46 | expr = build_int_cst (type, 0); |
76e616db BK |
47 | return expr; |
48 | } | |
49 | ||
f5963e61 | 50 | switch (TREE_CODE (TREE_TYPE (expr))) |
76e616db | 51 | { |
f5963e61 JL |
52 | case POINTER_TYPE: |
53 | case REFERENCE_TYPE: | |
54 | return build1 (NOP_EXPR, type, expr); | |
55 | ||
56 | case INTEGER_TYPE: | |
57 | case ENUMERAL_TYPE: | |
58 | case BOOLEAN_TYPE: | |
59 | case CHAR_TYPE: | |
60 | if (TYPE_PRECISION (TREE_TYPE (expr)) == POINTER_SIZE) | |
76e616db | 61 | return build1 (CONVERT_EXPR, type, expr); |
76e616db | 62 | |
f5963e61 JL |
63 | return |
64 | convert_to_pointer (type, | |
ae2bcd98 | 65 | convert (lang_hooks.types.type_for_size |
b0c48229 | 66 | (POINTER_SIZE, 0), expr)); |
76e616db | 67 | |
f5963e61 JL |
68 | default: |
69 | error ("cannot convert to a pointer type"); | |
70 | return convert_to_pointer (type, integer_zero_node); | |
71 | } | |
76e616db BK |
72 | } |
73 | ||
4977bab6 | 74 | /* Avoid any floating point extensions from EXP. */ |
77f9af81 | 75 | tree |
159b3be1 | 76 | strip_float_extensions (tree exp) |
4977bab6 ZW |
77 | { |
78 | tree sub, expt, subt; | |
79 | ||
77f9af81 JH |
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) | |
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 | ||
7c243eef RS |
101 | if (TREE_CODE (exp) != NOP_EXPR |
102 | && TREE_CODE (exp) != CONVERT_EXPR) | |
4977bab6 ZW |
103 | return exp; |
104 | ||
105 | sub = TREE_OPERAND (exp, 0); | |
106 | subt = TREE_TYPE (sub); | |
107 | expt = TREE_TYPE (exp); | |
108 | ||
109 | if (!FLOAT_TYPE_P (subt)) | |
110 | return exp; | |
111 | ||
112 | if (TYPE_PRECISION (subt) > TYPE_PRECISION (expt)) | |
113 | return exp; | |
114 | ||
115 | return strip_float_extensions (sub); | |
116 | } | |
117 | ||
118 | ||
76e616db BK |
119 | /* Convert EXPR to some floating-point type TYPE. |
120 | ||
121 | EXPR must be float, integer, or enumeral; | |
0f41302f | 122 | in other cases error is called. */ |
76e616db BK |
123 | |
124 | tree | |
159b3be1 | 125 | convert_to_real (tree type, tree expr) |
76e616db | 126 | { |
27a6aa72 | 127 | enum built_in_function fcode = builtin_mathfn_code (expr); |
4977bab6 ZW |
128 | tree itype = TREE_TYPE (expr); |
129 | ||
4b207444 JH |
130 | /* Disable until we figure out how to decide whether the functions are |
131 | present in runtime. */ | |
4977bab6 | 132 | /* Convert (float)sqrt((double)x) where x is float into sqrtf(x) */ |
78bd5210 | 133 | if (optimize |
4977bab6 ZW |
134 | && (TYPE_MODE (type) == TYPE_MODE (double_type_node) |
135 | || TYPE_MODE (type) == TYPE_MODE (float_type_node))) | |
136 | { | |
b3810360 KG |
137 | switch (fcode) |
138 | { | |
139 | #define CASE_MATHFN(FN) case BUILT_IN_##FN: case BUILT_IN_##FN##L: | |
1fb7e3af KG |
140 | CASE_MATHFN (ACOS) |
141 | CASE_MATHFN (ACOSH) | |
142 | CASE_MATHFN (ASIN) | |
143 | CASE_MATHFN (ASINH) | |
144 | CASE_MATHFN (ATAN) | |
145 | CASE_MATHFN (ATANH) | |
146 | CASE_MATHFN (CBRT) | |
b3810360 | 147 | CASE_MATHFN (COS) |
1fb7e3af KG |
148 | CASE_MATHFN (COSH) |
149 | CASE_MATHFN (ERF) | |
150 | CASE_MATHFN (ERFC) | |
b3810360 | 151 | CASE_MATHFN (EXP) |
1fb7e3af KG |
152 | CASE_MATHFN (EXP10) |
153 | CASE_MATHFN (EXP2) | |
154 | CASE_MATHFN (EXPM1) | |
155 | CASE_MATHFN (FABS) | |
156 | CASE_MATHFN (GAMMA) | |
157 | CASE_MATHFN (J0) | |
158 | CASE_MATHFN (J1) | |
159 | CASE_MATHFN (LGAMMA) | |
b3810360 | 160 | CASE_MATHFN (LOG) |
1fb7e3af KG |
161 | CASE_MATHFN (LOG10) |
162 | CASE_MATHFN (LOG1P) | |
163 | CASE_MATHFN (LOG2) | |
164 | CASE_MATHFN (LOGB) | |
165 | CASE_MATHFN (POW10) | |
166 | CASE_MATHFN (SIN) | |
167 | CASE_MATHFN (SINH) | |
168 | CASE_MATHFN (SQRT) | |
169 | CASE_MATHFN (TAN) | |
170 | CASE_MATHFN (TANH) | |
171 | CASE_MATHFN (TGAMMA) | |
172 | CASE_MATHFN (Y0) | |
173 | CASE_MATHFN (Y1) | |
b3810360 | 174 | #undef CASE_MATHFN |
4977bab6 | 175 | { |
b3810360 KG |
176 | tree arg0 = strip_float_extensions (TREE_VALUE (TREE_OPERAND (expr, 1))); |
177 | tree newtype = type; | |
178 | ||
179 | /* We have (outertype)sqrt((innertype)x). Choose the wider mode from | |
180 | the both as the safe type for operation. */ | |
181 | if (TYPE_PRECISION (TREE_TYPE (arg0)) > TYPE_PRECISION (type)) | |
182 | newtype = TREE_TYPE (arg0); | |
183 | ||
184 | /* Be careful about integer to fp conversions. | |
185 | These may overflow still. */ | |
186 | if (FLOAT_TYPE_P (TREE_TYPE (arg0)) | |
187 | && TYPE_PRECISION (newtype) < TYPE_PRECISION (itype) | |
188 | && (TYPE_MODE (newtype) == TYPE_MODE (double_type_node) | |
189 | || TYPE_MODE (newtype) == TYPE_MODE (float_type_node))) | |
190 | { | |
191 | tree arglist; | |
192 | tree fn = mathfn_built_in (newtype, fcode); | |
193 | ||
194 | if (fn) | |
195 | { | |
196 | arglist = build_tree_list (NULL_TREE, fold (convert_to_real (newtype, arg0))); | |
197 | expr = build_function_call_expr (fn, arglist); | |
198 | if (newtype == type) | |
199 | return expr; | |
200 | } | |
201 | } | |
4977bab6 | 202 | } |
b3810360 KG |
203 | default: |
204 | break; | |
4977bab6 ZW |
205 | } |
206 | } | |
27a6aa72 JH |
207 | if (optimize |
208 | && (((fcode == BUILT_IN_FLOORL | |
209 | || fcode == BUILT_IN_CEILL | |
b57051b2 | 210 | || fcode == BUILT_IN_ROUNDL |
d093738d | 211 | || fcode == BUILT_IN_RINTL |
b57051b2 KG |
212 | || fcode == BUILT_IN_TRUNCL |
213 | || fcode == BUILT_IN_NEARBYINTL) | |
27a6aa72 JH |
214 | && (TYPE_MODE (type) == TYPE_MODE (double_type_node) |
215 | || TYPE_MODE (type) == TYPE_MODE (float_type_node))) | |
216 | || ((fcode == BUILT_IN_FLOOR | |
217 | || fcode == BUILT_IN_CEIL | |
218 | || fcode == BUILT_IN_ROUND | |
d093738d | 219 | || fcode == BUILT_IN_RINT |
27a6aa72 JH |
220 | || fcode == BUILT_IN_TRUNC |
221 | || fcode == BUILT_IN_NEARBYINT) | |
222 | && (TYPE_MODE (type) == TYPE_MODE (float_type_node))))) | |
223 | { | |
224 | tree fn = mathfn_built_in (type, fcode); | |
225 | ||
226 | if (fn) | |
227 | { | |
228 | tree arg0 = strip_float_extensions (TREE_VALUE (TREE_OPERAND (expr, | |
159b3be1 | 229 | 1))); |
27a6aa72 | 230 | tree arglist = build_tree_list (NULL_TREE, |
159b3be1 | 231 | fold (convert_to_real (type, arg0))); |
27a6aa72 JH |
232 | |
233 | return build_function_call_expr (fn, arglist); | |
234 | } | |
235 | } | |
4977bab6 ZW |
236 | |
237 | /* Propagate the cast into the operation. */ | |
238 | if (itype != type && FLOAT_TYPE_P (type)) | |
239 | switch (TREE_CODE (expr)) | |
240 | { | |
beb235f8 | 241 | /* Convert (float)-x into -(float)x. This is always safe. */ |
4977bab6 ZW |
242 | case ABS_EXPR: |
243 | case NEGATE_EXPR: | |
b1a6f8db JH |
244 | if (TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (expr))) |
245 | return build1 (TREE_CODE (expr), type, | |
246 | fold (convert_to_real (type, | |
247 | TREE_OPERAND (expr, 0)))); | |
248 | break; | |
beb235f8 | 249 | /* Convert (outertype)((innertype0)a+(innertype1)b) |
4977bab6 ZW |
250 | into ((newtype)a+(newtype)b) where newtype |
251 | is the widest mode from all of these. */ | |
252 | case PLUS_EXPR: | |
253 | case MINUS_EXPR: | |
254 | case MULT_EXPR: | |
255 | case RDIV_EXPR: | |
256 | { | |
257 | tree arg0 = strip_float_extensions (TREE_OPERAND (expr, 0)); | |
258 | tree arg1 = strip_float_extensions (TREE_OPERAND (expr, 1)); | |
259 | ||
260 | if (FLOAT_TYPE_P (TREE_TYPE (arg0)) | |
261 | && FLOAT_TYPE_P (TREE_TYPE (arg1))) | |
262 | { | |
263 | tree newtype = type; | |
264 | if (TYPE_PRECISION (TREE_TYPE (arg0)) > TYPE_PRECISION (newtype)) | |
265 | newtype = TREE_TYPE (arg0); | |
266 | if (TYPE_PRECISION (TREE_TYPE (arg1)) > TYPE_PRECISION (newtype)) | |
267 | newtype = TREE_TYPE (arg1); | |
268 | if (TYPE_PRECISION (newtype) < TYPE_PRECISION (itype)) | |
269 | { | |
3244e67d RS |
270 | expr = build2 (TREE_CODE (expr), newtype, |
271 | fold (convert_to_real (newtype, arg0)), | |
272 | fold (convert_to_real (newtype, arg1))); | |
4977bab6 ZW |
273 | if (newtype == type) |
274 | return expr; | |
275 | } | |
276 | } | |
277 | } | |
278 | break; | |
279 | default: | |
280 | break; | |
281 | } | |
282 | ||
f5963e61 JL |
283 | switch (TREE_CODE (TREE_TYPE (expr))) |
284 | { | |
285 | case REAL_TYPE: | |
286 | return build1 (flag_float_store ? CONVERT_EXPR : NOP_EXPR, | |
287 | type, expr); | |
288 | ||
289 | case INTEGER_TYPE: | |
290 | case ENUMERAL_TYPE: | |
291 | case BOOLEAN_TYPE: | |
292 | case CHAR_TYPE: | |
293 | return build1 (FLOAT_EXPR, type, expr); | |
294 | ||
295 | case COMPLEX_TYPE: | |
296 | return convert (type, | |
297 | fold (build1 (REALPART_EXPR, | |
298 | TREE_TYPE (TREE_TYPE (expr)), expr))); | |
299 | ||
300 | case POINTER_TYPE: | |
301 | case REFERENCE_TYPE: | |
302 | error ("pointer value used where a floating point value was expected"); | |
303 | return convert_to_real (type, integer_zero_node); | |
304 | ||
305 | default: | |
306 | error ("aggregate value used where a float was expected"); | |
307 | return convert_to_real (type, integer_zero_node); | |
308 | } | |
76e616db BK |
309 | } |
310 | ||
311 | /* Convert EXPR to some integer (or enum) type TYPE. | |
312 | ||
0b4565c9 BS |
313 | EXPR must be pointer, integer, discrete (enum, char, or bool), float, or |
314 | vector; in other cases error is called. | |
76e616db BK |
315 | |
316 | The result of this is always supposed to be a newly created tree node | |
317 | not in use in any existing structure. */ | |
318 | ||
319 | tree | |
159b3be1 | 320 | convert_to_integer (tree type, tree expr) |
76e616db | 321 | { |
f5963e61 JL |
322 | enum tree_code ex_form = TREE_CODE (expr); |
323 | tree intype = TREE_TYPE (expr); | |
770ae6cc RK |
324 | unsigned int inprec = TYPE_PRECISION (intype); |
325 | unsigned int outprec = TYPE_PRECISION (type); | |
76e616db | 326 | |
9c4cb3a3 MM |
327 | /* An INTEGER_TYPE cannot be incomplete, but an ENUMERAL_TYPE can |
328 | be. Consider `enum E = { a, b = (enum E) 3 };'. */ | |
d0f062fb | 329 | if (!COMPLETE_TYPE_P (type)) |
9c4cb3a3 MM |
330 | { |
331 | error ("conversion to incomplete type"); | |
332 | return error_mark_node; | |
333 | } | |
334 | ||
332d782c KG |
335 | /* Convert e.g. (long)round(d) -> lround(d). */ |
336 | /* If we're converting to char, we may encounter differing behavior | |
337 | between converting from double->char vs double->long->char. | |
338 | We're in "undefined" territory but we prefer to be conservative, | |
339 | so only proceed in "unsafe" math mode. */ | |
340 | if (optimize | |
341 | && (flag_unsafe_math_optimizations | |
d2be4368 KG |
342 | || (long_integer_type_node |
343 | && outprec >= TYPE_PRECISION (long_integer_type_node)))) | |
332d782c KG |
344 | { |
345 | tree s_expr = strip_float_extensions (expr); | |
346 | tree s_intype = TREE_TYPE (s_expr); | |
347 | const enum built_in_function fcode = builtin_mathfn_code (s_expr); | |
348 | tree fn = 0; | |
349 | ||
350 | switch (fcode) | |
351 | { | |
f94b1661 UB |
352 | case BUILT_IN_CEIL: case BUILT_IN_CEILF: case BUILT_IN_CEILL: |
353 | if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (long_long_integer_type_node)) | |
354 | fn = mathfn_built_in (s_intype, BUILT_IN_LLCEIL); | |
355 | else | |
356 | fn = mathfn_built_in (s_intype, BUILT_IN_LCEIL); | |
357 | break; | |
358 | ||
d8b42d06 UB |
359 | case BUILT_IN_FLOOR: case BUILT_IN_FLOORF: case BUILT_IN_FLOORL: |
360 | if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (long_long_integer_type_node)) | |
361 | fn = mathfn_built_in (s_intype, BUILT_IN_LLFLOOR); | |
362 | else | |
363 | fn = mathfn_built_in (s_intype, BUILT_IN_LFLOOR); | |
364 | break; | |
365 | ||
332d782c KG |
366 | case BUILT_IN_ROUND: case BUILT_IN_ROUNDF: case BUILT_IN_ROUNDL: |
367 | if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (long_long_integer_type_node)) | |
368 | fn = mathfn_built_in (s_intype, BUILT_IN_LLROUND); | |
369 | else | |
370 | fn = mathfn_built_in (s_intype, BUILT_IN_LROUND); | |
371 | break; | |
372 | ||
373 | case BUILT_IN_RINT: case BUILT_IN_RINTF: case BUILT_IN_RINTL: | |
374 | /* Only convert rint* if we can ignore math exceptions. */ | |
375 | if (flag_trapping_math) | |
376 | break; | |
377 | /* ... Fall through ... */ | |
378 | case BUILT_IN_NEARBYINT: case BUILT_IN_NEARBYINTF: case BUILT_IN_NEARBYINTL: | |
379 | if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (long_long_integer_type_node)) | |
380 | fn = mathfn_built_in (s_intype, BUILT_IN_LLRINT); | |
381 | else | |
382 | fn = mathfn_built_in (s_intype, BUILT_IN_LRINT); | |
383 | break; | |
384 | default: | |
385 | break; | |
386 | } | |
387 | ||
388 | if (fn) | |
389 | { | |
390 | tree arglist = TREE_OPERAND (s_expr, 1); | |
391 | tree newexpr = build_function_call_expr (fn, arglist); | |
392 | return convert_to_integer (type, newexpr); | |
393 | } | |
394 | } | |
395 | ||
f5963e61 | 396 | switch (TREE_CODE (intype)) |
76e616db | 397 | { |
f5963e61 JL |
398 | case POINTER_TYPE: |
399 | case REFERENCE_TYPE: | |
76e616db BK |
400 | if (integer_zerop (expr)) |
401 | expr = integer_zero_node; | |
402 | else | |
ae2bcd98 | 403 | expr = fold (build1 (CONVERT_EXPR, |
0948e392 | 404 | lang_hooks.types.type_for_size (POINTER_SIZE, 0), |
ae2bcd98 | 405 | expr)); |
76e616db | 406 | |
f5963e61 | 407 | return convert_to_integer (type, expr); |
76e616db | 408 | |
f5963e61 JL |
409 | case INTEGER_TYPE: |
410 | case ENUMERAL_TYPE: | |
411 | case BOOLEAN_TYPE: | |
412 | case CHAR_TYPE: | |
413 | /* If this is a logical operation, which just returns 0 or 1, we can | |
a338ab5a | 414 | change the type of the expression. */ |
76e616db | 415 | |
6615c446 | 416 | if (TREE_CODE_CLASS (ex_form) == tcc_comparison) |
76e616db | 417 | { |
5dfa45d0 | 418 | expr = copy_node (expr); |
76e616db BK |
419 | TREE_TYPE (expr) = type; |
420 | return expr; | |
421 | } | |
f5963e61 | 422 | |
f5963e61 JL |
423 | /* If we are widening the type, put in an explicit conversion. |
424 | Similarly if we are not changing the width. After this, we know | |
425 | we are truncating EXPR. */ | |
426 | ||
76e616db | 427 | else if (outprec >= inprec) |
4b0d3cbe MM |
428 | { |
429 | enum tree_code code; | |
430 | ||
431 | /* If the precision of the EXPR's type is K bits and the | |
432 | destination mode has more bits, and the sign is changing, | |
433 | it is not safe to use a NOP_EXPR. For example, suppose | |
434 | that EXPR's type is a 3-bit unsigned integer type, the | |
435 | TYPE is a 3-bit signed integer type, and the machine mode | |
436 | for the types is 8-bit QImode. In that case, the | |
437 | conversion necessitates an explicit sign-extension. In | |
438 | the signed-to-unsigned case the high-order bits have to | |
439 | be cleared. */ | |
8df83eae | 440 | if (TYPE_UNSIGNED (type) != TYPE_UNSIGNED (TREE_TYPE (expr)) |
4b0d3cbe MM |
441 | && (TYPE_PRECISION (TREE_TYPE (expr)) |
442 | != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr))))) | |
443 | code = CONVERT_EXPR; | |
444 | else | |
445 | code = NOP_EXPR; | |
446 | ||
447 | return build1 (code, type, expr); | |
448 | } | |
76e616db | 449 | |
1c013b45 RK |
450 | /* If TYPE is an enumeral type or a type with a precision less |
451 | than the number of bits in its mode, do the conversion to the | |
452 | type corresponding to its mode, then do a nop conversion | |
453 | to TYPE. */ | |
454 | else if (TREE_CODE (type) == ENUMERAL_TYPE | |
455 | || outprec != GET_MODE_BITSIZE (TYPE_MODE (type))) | |
456 | return build1 (NOP_EXPR, type, | |
ae2bcd98 | 457 | convert (lang_hooks.types.type_for_mode |
8df83eae | 458 | (TYPE_MODE (type), TYPE_UNSIGNED (type)), |
1c013b45 RK |
459 | expr)); |
460 | ||
ab29fdfc RK |
461 | /* Here detect when we can distribute the truncation down past some |
462 | arithmetic. For example, if adding two longs and converting to an | |
463 | int, we can equally well convert both to ints and then add. | |
464 | For the operations handled here, such truncation distribution | |
465 | is always safe. | |
466 | It is desirable in these cases: | |
467 | 1) when truncating down to full-word from a larger size | |
468 | 2) when truncating takes no work. | |
469 | 3) when at least one operand of the arithmetic has been extended | |
470 | (as by C's default conversions). In this case we need two conversions | |
471 | if we do the arithmetic as already requested, so we might as well | |
472 | truncate both and then combine. Perhaps that way we need only one. | |
473 | ||
474 | Note that in general we cannot do the arithmetic in a type | |
475 | shorter than the desired result of conversion, even if the operands | |
476 | are both extended from a shorter type, because they might overflow | |
477 | if combined in that type. The exceptions to this--the times when | |
478 | two narrow values can be combined in their narrow type even to | |
479 | make a wider result--are handled by "shorten" in build_binary_op. */ | |
76e616db BK |
480 | |
481 | switch (ex_form) | |
482 | { | |
483 | case RSHIFT_EXPR: | |
484 | /* We can pass truncation down through right shifting | |
485 | when the shift count is a nonpositive constant. */ | |
486 | if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST | |
ab29fdfc RK |
487 | && tree_int_cst_lt (TREE_OPERAND (expr, 1), |
488 | convert (TREE_TYPE (TREE_OPERAND (expr, 1)), | |
489 | integer_one_node))) | |
76e616db BK |
490 | goto trunc1; |
491 | break; | |
492 | ||
493 | case LSHIFT_EXPR: | |
494 | /* We can pass truncation down through left shifting | |
43e4a9d8 EB |
495 | when the shift count is a nonnegative constant and |
496 | the target type is unsigned. */ | |
76e616db | 497 | if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST |
ab29fdfc | 498 | && tree_int_cst_sgn (TREE_OPERAND (expr, 1)) >= 0 |
8df83eae | 499 | && TYPE_UNSIGNED (type) |
76e616db BK |
500 | && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST) |
501 | { | |
502 | /* If shift count is less than the width of the truncated type, | |
503 | really shift. */ | |
504 | if (tree_int_cst_lt (TREE_OPERAND (expr, 1), TYPE_SIZE (type))) | |
505 | /* In this case, shifting is like multiplication. */ | |
506 | goto trunc1; | |
507 | else | |
d9a9c5a7 RK |
508 | { |
509 | /* If it is >= that width, result is zero. | |
510 | Handling this with trunc1 would give the wrong result: | |
511 | (int) ((long long) a << 32) is well defined (as 0) | |
512 | but (int) a << 32 is undefined and would get a | |
513 | warning. */ | |
514 | ||
515 | tree t = convert_to_integer (type, integer_zero_node); | |
516 | ||
517 | /* If the original expression had side-effects, we must | |
518 | preserve it. */ | |
519 | if (TREE_SIDE_EFFECTS (expr)) | |
3244e67d | 520 | return build2 (COMPOUND_EXPR, type, expr, t); |
d9a9c5a7 RK |
521 | else |
522 | return t; | |
523 | } | |
76e616db BK |
524 | } |
525 | break; | |
526 | ||
527 | case MAX_EXPR: | |
528 | case MIN_EXPR: | |
529 | case MULT_EXPR: | |
530 | { | |
531 | tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type); | |
532 | tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type); | |
533 | ||
534 | /* Don't distribute unless the output precision is at least as big | |
535 | as the actual inputs. Otherwise, the comparison of the | |
536 | truncated values will be wrong. */ | |
537 | if (outprec >= TYPE_PRECISION (TREE_TYPE (arg0)) | |
538 | && outprec >= TYPE_PRECISION (TREE_TYPE (arg1)) | |
539 | /* If signedness of arg0 and arg1 don't match, | |
540 | we can't necessarily find a type to compare them in. */ | |
8df83eae RK |
541 | && (TYPE_UNSIGNED (TREE_TYPE (arg0)) |
542 | == TYPE_UNSIGNED (TREE_TYPE (arg1)))) | |
76e616db BK |
543 | goto trunc1; |
544 | break; | |
545 | } | |
546 | ||
547 | case PLUS_EXPR: | |
548 | case MINUS_EXPR: | |
549 | case BIT_AND_EXPR: | |
550 | case BIT_IOR_EXPR: | |
551 | case BIT_XOR_EXPR: | |
76e616db BK |
552 | trunc1: |
553 | { | |
554 | tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type); | |
555 | tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type); | |
556 | ||
557 | if (outprec >= BITS_PER_WORD | |
558 | || TRULY_NOOP_TRUNCATION (outprec, inprec) | |
559 | || inprec > TYPE_PRECISION (TREE_TYPE (arg0)) | |
560 | || inprec > TYPE_PRECISION (TREE_TYPE (arg1))) | |
561 | { | |
562 | /* Do the arithmetic in type TYPEX, | |
563 | then convert result to TYPE. */ | |
b3694847 | 564 | tree typex = type; |
76e616db BK |
565 | |
566 | /* Can't do arithmetic in enumeral types | |
567 | so use an integer type that will hold the values. */ | |
568 | if (TREE_CODE (typex) == ENUMERAL_TYPE) | |
ae2bcd98 | 569 | typex = lang_hooks.types.type_for_size |
8df83eae | 570 | (TYPE_PRECISION (typex), TYPE_UNSIGNED (typex)); |
76e616db BK |
571 | |
572 | /* But now perhaps TYPEX is as wide as INPREC. | |
573 | In that case, do nothing special here. | |
574 | (Otherwise would recurse infinitely in convert. */ | |
575 | if (TYPE_PRECISION (typex) != inprec) | |
576 | { | |
577 | /* Don't do unsigned arithmetic where signed was wanted, | |
578 | or vice versa. | |
3cc247a8 | 579 | Exception: if both of the original operands were |
159b3be1 | 580 | unsigned then we can safely do the work as unsigned. |
43e4a9d8 EB |
581 | Exception: shift operations take their type solely |
582 | from the first argument. | |
583 | Exception: the LSHIFT_EXPR case above requires that | |
584 | we perform this operation unsigned lest we produce | |
585 | signed-overflow undefinedness. | |
76e616db BK |
586 | And we may need to do it as unsigned |
587 | if we truncate to the original size. */ | |
8df83eae RK |
588 | if (TYPE_UNSIGNED (TREE_TYPE (expr)) |
589 | || (TYPE_UNSIGNED (TREE_TYPE (arg0)) | |
590 | && (TYPE_UNSIGNED (TREE_TYPE (arg1)) | |
43e4a9d8 EB |
591 | || ex_form == LSHIFT_EXPR |
592 | || ex_form == RSHIFT_EXPR | |
593 | || ex_form == LROTATE_EXPR | |
594 | || ex_form == RROTATE_EXPR)) | |
595 | || ex_form == LSHIFT_EXPR) | |
ae2bcd98 | 596 | typex = lang_hooks.types.unsigned_type (typex); |
ceef8ce4 | 597 | else |
ae2bcd98 | 598 | typex = lang_hooks.types.signed_type (typex); |
76e616db | 599 | return convert (type, |
3244e67d RS |
600 | fold (build2 (ex_form, typex, |
601 | convert (typex, arg0), | |
602 | convert (typex, arg1)))); | |
76e616db BK |
603 | } |
604 | } | |
605 | } | |
606 | break; | |
607 | ||
608 | case NEGATE_EXPR: | |
609 | case BIT_NOT_EXPR: | |
d283912a RS |
610 | /* This is not correct for ABS_EXPR, |
611 | since we must test the sign before truncation. */ | |
76e616db | 612 | { |
b3694847 | 613 | tree typex = type; |
76e616db BK |
614 | |
615 | /* Can't do arithmetic in enumeral types | |
616 | so use an integer type that will hold the values. */ | |
617 | if (TREE_CODE (typex) == ENUMERAL_TYPE) | |
ae2bcd98 | 618 | typex = lang_hooks.types.type_for_size |
8df83eae | 619 | (TYPE_PRECISION (typex), TYPE_UNSIGNED (typex)); |
76e616db BK |
620 | |
621 | /* But now perhaps TYPEX is as wide as INPREC. | |
622 | In that case, do nothing special here. | |
623 | (Otherwise would recurse infinitely in convert. */ | |
624 | if (TYPE_PRECISION (typex) != inprec) | |
625 | { | |
626 | /* Don't do unsigned arithmetic where signed was wanted, | |
627 | or vice versa. */ | |
8df83eae | 628 | if (TYPE_UNSIGNED (TREE_TYPE (expr))) |
ae2bcd98 | 629 | typex = lang_hooks.types.unsigned_type (typex); |
ceef8ce4 | 630 | else |
ae2bcd98 | 631 | typex = lang_hooks.types.signed_type (typex); |
76e616db | 632 | return convert (type, |
95e78909 RK |
633 | fold (build1 (ex_form, typex, |
634 | convert (typex, | |
635 | TREE_OPERAND (expr, 0))))); | |
76e616db BK |
636 | } |
637 | } | |
638 | ||
639 | case NOP_EXPR: | |
3767c0fd R |
640 | /* Don't introduce a |
641 | "can't convert between vector values of different size" error. */ | |
642 | if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == VECTOR_TYPE | |
643 | && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_OPERAND (expr, 0)))) | |
644 | != GET_MODE_SIZE (TYPE_MODE (type)))) | |
645 | break; | |
76e616db BK |
646 | /* If truncating after truncating, might as well do all at once. |
647 | If truncating after extending, we may get rid of wasted work. */ | |
648 | return convert (type, get_unwidened (TREE_OPERAND (expr, 0), type)); | |
649 | ||
650 | case COND_EXPR: | |
f5963e61 JL |
651 | /* It is sometimes worthwhile to push the narrowing down through |
652 | the conditional and never loses. */ | |
3244e67d RS |
653 | return fold (build3 (COND_EXPR, type, TREE_OPERAND (expr, 0), |
654 | convert (type, TREE_OPERAND (expr, 1)), | |
655 | convert (type, TREE_OPERAND (expr, 2)))); | |
76e616db | 656 | |
31031edd JL |
657 | default: |
658 | break; | |
76e616db BK |
659 | } |
660 | ||
0b87eff5 | 661 | return build1 (CONVERT_EXPR, type, expr); |
76e616db | 662 | |
f5963e61 JL |
663 | case REAL_TYPE: |
664 | return build1 (FIX_TRUNC_EXPR, type, expr); | |
76e616db | 665 | |
f5963e61 JL |
666 | case COMPLEX_TYPE: |
667 | return convert (type, | |
668 | fold (build1 (REALPART_EXPR, | |
669 | TREE_TYPE (TREE_TYPE (expr)), expr))); | |
0b127821 | 670 | |
0b4565c9 | 671 | case VECTOR_TYPE: |
3a021db2 | 672 | if (!tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (TREE_TYPE (expr)))) |
0b4565c9 BS |
673 | { |
674 | error ("can't convert between vector values of different size"); | |
675 | return error_mark_node; | |
676 | } | |
677 | return build1 (NOP_EXPR, type, expr); | |
678 | ||
f5963e61 JL |
679 | default: |
680 | error ("aggregate value used where an integer was expected"); | |
681 | return convert (type, integer_zero_node); | |
682 | } | |
76e616db | 683 | } |
0b127821 RS |
684 | |
685 | /* Convert EXPR to the complex type TYPE in the usual ways. */ | |
686 | ||
687 | tree | |
159b3be1 | 688 | convert_to_complex (tree type, tree expr) |
0b127821 | 689 | { |
0b127821 | 690 | tree subtype = TREE_TYPE (type); |
159b3be1 | 691 | |
f5963e61 | 692 | switch (TREE_CODE (TREE_TYPE (expr))) |
0b127821 | 693 | { |
f5963e61 JL |
694 | case REAL_TYPE: |
695 | case INTEGER_TYPE: | |
696 | case ENUMERAL_TYPE: | |
697 | case BOOLEAN_TYPE: | |
698 | case CHAR_TYPE: | |
3244e67d RS |
699 | return build2 (COMPLEX_EXPR, type, convert (subtype, expr), |
700 | convert (subtype, integer_zero_node)); | |
0b127821 | 701 | |
f5963e61 JL |
702 | case COMPLEX_TYPE: |
703 | { | |
704 | tree elt_type = TREE_TYPE (TREE_TYPE (expr)); | |
705 | ||
706 | if (TYPE_MAIN_VARIANT (elt_type) == TYPE_MAIN_VARIANT (subtype)) | |
707 | return expr; | |
708 | else if (TREE_CODE (expr) == COMPLEX_EXPR) | |
3244e67d RS |
709 | return fold (build2 (COMPLEX_EXPR, type, |
710 | convert (subtype, TREE_OPERAND (expr, 0)), | |
711 | convert (subtype, TREE_OPERAND (expr, 1)))); | |
f5963e61 JL |
712 | else |
713 | { | |
714 | expr = save_expr (expr); | |
715 | return | |
3244e67d RS |
716 | fold (build2 (COMPLEX_EXPR, type, |
717 | convert (subtype, | |
718 | fold (build1 (REALPART_EXPR, | |
719 | TREE_TYPE (TREE_TYPE (expr)), | |
720 | expr))), | |
721 | convert (subtype, | |
722 | fold (build1 (IMAGPART_EXPR, | |
723 | TREE_TYPE (TREE_TYPE (expr)), | |
724 | expr))))); | |
f5963e61 JL |
725 | } |
726 | } | |
0b127821 | 727 | |
f5963e61 JL |
728 | case POINTER_TYPE: |
729 | case REFERENCE_TYPE: | |
730 | error ("pointer value used where a complex was expected"); | |
731 | return convert_to_complex (type, integer_zero_node); | |
732 | ||
733 | default: | |
734 | error ("aggregate value used where a complex was expected"); | |
735 | return convert_to_complex (type, integer_zero_node); | |
736 | } | |
0b127821 | 737 | } |
0b4565c9 BS |
738 | |
739 | /* Convert EXPR to the vector type TYPE in the usual ways. */ | |
740 | ||
741 | tree | |
159b3be1 | 742 | convert_to_vector (tree type, tree expr) |
0b4565c9 | 743 | { |
0b4565c9 BS |
744 | switch (TREE_CODE (TREE_TYPE (expr))) |
745 | { | |
746 | case INTEGER_TYPE: | |
747 | case VECTOR_TYPE: | |
3a021db2 | 748 | if (!tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (TREE_TYPE (expr)))) |
0b4565c9 BS |
749 | { |
750 | error ("can't convert between vector values of different size"); | |
751 | return error_mark_node; | |
752 | } | |
753 | return build1 (NOP_EXPR, type, expr); | |
754 | ||
755 | default: | |
756 | error ("can't convert value to a vector"); | |
273d67e7 | 757 | return error_mark_node; |
0b4565c9 BS |
758 | } |
759 | } |