2 * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * @brief Representation of and static computations on target machine
25 * @author Mathias Heil
28 * Tarvals represent target machine values. They are typed by modes.
29 * Tarvals only represent values of mode_sort:
36 * In case of references the module accepts an entity to represent the
38 * Furthermore, computations and conversions of these values can
42 * The original tv module originated in the fiasco compiler written ...
43 * This is the new version, described in the tech report 1999-14 by ...
47 * irmode.h for the modes definitions
48 * irnode.h for the pn_Cmp table
53 #include "firm_types.h"
56 /* ************************ Constructors for tarvals ************************ */
59 * Constructor function for new tarvals.
61 * @param str The string representing the target value
62 * @param len The length of the string
63 * @param mode The mode requested for the result tarval
65 * This function creates a new tarval representing the value represented
66 * by a CString, aka char array. If a tarval representing this value already
67 * exists, this tarval is returned instead of a new one. So tarvals are
68 * directly comparable since their representation is unique.
70 * This function accepts the following strings:
72 * if mode is int_number:
73 * - 0(x|X)[0-9a-fA-F]+ (hexadecimal representation)
74 * - 0[0-7]* (octal representation)
75 * - (+|-)?[1-9][0-9]* (decimal representation)
77 * if mode if float_number:
78 * - (+|-)?(decimal int) (. (decimal int))? ((e|E)(+|-)?(decimal int))?
80 * if mode is boolean: true, True, TRUE ... False... 0, 1,
82 * if mode is reference: hexadecimal of decimal number as int
84 * if mode is character: hex or dec
86 * Leading and/or trailing spaces are ignored
89 * A tarval of proper type representing the requested value is returned.
90 * Tarvals are unique, so for any value/mode pair at most one tarval will
91 * exist, which will be returned upon further requests with an identical
95 * If the string is not representable in the given mode an assertion is
96 * thrown in assert build.
99 * irmode.h for predefined modes
100 * new_tarval_from_long()
101 * new_tarval_from_double()
103 tarval *new_tarval_from_str(const char *str, size_t len, ir_mode *mode);
106 * Constructor function for new tarvals
108 * @param l The long representing the value
109 * @param mode The mode requested for the result tarval
111 * This function creates a new tarval representing the value represented
112 * by a long integer. If a tarval representing this value already exists,
113 * this tarval is returned instead of a new one. So tarvals are directly
114 * comparable since their representation is unique.
117 * A tarval of proper type representing the requested value is returned.
118 * Tarvals are unique, so for any value/mode pair at most one tarval will
119 * exist, which will be returned upon further requests with an identical
123 * If the long is not representable in the given mode an assertion is
124 * thrown in assert build.
127 * irmode.h for predefined modes
128 * new_tarval_from_str()
129 * new_tarval_from_double()
132 tarval *new_tarval_from_long(long l, ir_mode *mode);
134 /** Return value as long if possible.
136 * This returns a long int with the value represented value, or
137 * gibberish, depending on the size of long int and the size of the
138 * stored value. It works for e.g. 1 as mode_Ls, but might not work for
139 * get_mode_max(mode_Ls).
140 * This will overflow silently, so use only if you know what
141 * you are doing! (better check with tarval_is_long()...)
142 * Works only for int modes, even not for character modes!
144 long get_tarval_long(tarval *tv);
147 * This validates if get_tarval_long() will return a satisfying
148 * result. I.e. if tv is an int_number and between min, max
149 * of long int (signed!)
151 int tarval_is_long(tarval *tv);
154 * Constructor function for new tarvals.
156 * @param d The (long) double representing the value
157 * @param mode The mode requested for the result tarval
159 * This function creates a new tarval representing the value represented
160 * by a (long) double. If a tarval representing this value already exists,
161 * this tarval is returned instead of a new one. So tarvals are directly
162 * comparable since their representation is unique.
163 * Only modes of sort float_number can be constructed this way.
166 * A tarval of proper type representing the requested value is returned.
167 * Tarvals are unique, so for any value/mode pair at most one tarval will
168 * exist, which will be returned upon further requests with an identical
172 * If the (long) double is not representable in the given mode an assertion
173 * is thrown. This will happen for any mode not of sort float_number.
176 * irmode.h for predefined values
177 * new_tarval_from_str()
178 * new_tarval_from_long()
180 tarval *new_tarval_from_double(long double d, ir_mode *mode);
183 * This returns a double with the value represented value, or
184 * gibberish, depending on the size of double and the size of the
186 * This will overflow silently, so use only if you know what
187 * you are doing! (better check with tarval_is_long...)
189 long double get_tarval_double(tarval *tv);
192 * This validates if tarval_to_double() will return a satisfying
193 * result. I.e. if tv is an float_number and between min, max
196 int tarval_is_double(tarval *tv);
199 /** ********** Access routines for tarval fields ********** **/
207 * ir_mode *get_tarval_mode(tarval *tv)
211 * These are access function for tarval struct members. It is encouraged
212 * to use them instead of direct access to the struct fields.
215 * tv - The tarval to access fields of
218 * get_tv_mode: The mode of the tarval
224 /** Returns the mode of the tarval. */
225 ir_mode *get_tarval_mode (const tarval *tv);
227 /** Returns the contents of the 'link' field of the tarval */
228 /* void *get_tarval_link (tarval*); */
230 /* Testing properties of the represented values */
233 * Returns 1 if tv is negative
235 * @param a the tarval
237 int tarval_is_negative(tarval *a);
240 * Returns 1 if tv is null
242 * @param a the tarval
244 int tarval_is_null(tarval *a);
247 * Returns 1 if tv is the "one"
249 * @param a the tarval
251 int tarval_is_one(tarval *a);
253 /** The 'bad' tarval. */
254 extern tarval *tarval_bad;
255 /** Returns the 'bad tarval. */
256 tarval *get_tarval_bad(void);
258 /** The 'undefined' tarval. */
259 extern tarval *tarval_undefined;
260 /** Returns the 'undefined' tarval. */
261 tarval *get_tarval_undefined(void);
263 /** The mode_b tarval 'false'. */
264 extern tarval *tarval_b_false;
266 /** Returns the mode_b tarval 'false'. */
267 tarval *get_tarval_b_false(void);
269 /** The mode_b tarval 'true'. */
270 extern tarval *tarval_b_true;
271 /** Returns the mode_b tarval 'true'. */
272 tarval *get_tarval_b_true(void);
274 /* These functions calculate and return a tarval representing the requested
276 * The functions get_mode_{Max,Min,...} return tarvals retrieved from these
277 * functions, but these are stored on initialization of the irmode module and
278 * therefore the irmode functions should be preferred to the functions below. */
280 /** Returns the maximum value of a given mode. */
281 tarval *get_tarval_max(ir_mode *mode);
283 /** Returns the minimum value of a given mode. */
284 tarval *get_tarval_min(ir_mode *mode);
286 /** Returns the 0 value (additive neutral) of a given mode.
287 For reference modes, the NULL value is returned (old tarval_P_void) */
288 tarval *get_tarval_null(ir_mode *mode);
290 /** Returns the 1 value (multiplicative neutral) of a given mode. */
291 tarval *get_tarval_one(ir_mode *mode);
293 /** Returns the -1 value (multiplicative neutral) of a given mode.
294 * Returns tarval bad for unsigned modes */
295 tarval *get_tarval_minus_one(ir_mode *mode);
297 /** Return quite nan for float_number modes. */
298 tarval *get_tarval_nan(ir_mode *mode);
300 /** Return +inf for float_number modes. */
301 tarval *get_tarval_plus_inf(ir_mode *mode);
303 /** Return -inf for float_number modes. */
304 tarval *get_tarval_minus_inf(ir_mode *mode);
306 /* ******************** Arithmetic operations on tarvals ******************** */
308 typedef enum _tarval_int_overflow_mode_t {
309 TV_OVERFLOW_BAD, /**< tarval module will return tarval_bad if a overflow occurs */
310 TV_OVERFLOW_WRAP, /**< tarval module will overflow will be ignored, wrap around occurs */
311 TV_OVERFLOW_SATURATE /**< tarval module will saturate the overflow */
312 } tarval_int_overflow_mode_t;
315 * Sets the overflow mode for integer operations.
317 void tarval_set_integer_overflow_mode(tarval_int_overflow_mode_t ov_mode);
320 * Get the overflow mode for integer operations.
322 tarval_int_overflow_mode_t tarval_get_integer_overflow_mode(void);
325 * Compares two tarvals
327 * Compare a with b and return a pn_Cmp describing the relation
328 * between a and b. This is either pn_Cmp_Uo, pn_Cmp_Lt, pn_Cmp_Eq, pn_Cmp_Gt,
329 * or pn_Cmp_False if a or b are symbolic pointers which can not be compared at all.
331 * @param a A tarval to be compared
332 * @param b A tarval to be compared
335 * The pn_Cmp best describing the relation between a and b is returned.
336 * This means the mode with the least bits set is returned, e.g. if the
337 * tarvals are equal the pn_Cmp 'pn_Cmp_Eq' is returned, not 'pn_Cmp_Ge' which
338 * indicates 'greater or equal'
341 * irnode.h for the definition of pn_Cmp
343 pn_Cmp tarval_cmp(tarval *a, tarval *b);
346 * Converts a tarval to another mode.
348 * Convert tarval 'src' to mode 'mode', this will succeed if and only if mode
349 * 'mode' is wider than the mode of src, as defined in the firm documentation
350 * and as returned by the function mode_is_smaller defined in irmode.h.
352 * @param src The tarval to convert
353 * @param mode Tho mode to convert to
356 * If a tarval of mode 'mode' with the result of the conversion of the 'src'
357 * tarvals value already exists, it will be returned, else a new tarval is
358 * constructed and returned
361 * Illegal conversations will trigger an assertion
364 * FIRM documentation for conversion rules
365 * mode_is_smaller defined in irmode.h
367 tarval *tarval_convert_to(tarval *src, ir_mode *mode);
370 * These function implement basic computations representable as opcodes
376 * a - the tarval to operate on
379 * a - the first operand tarval
380 * b - the second operand tarval
383 * If necessary a new tarval is constructed for the resulting value,
384 * or the one already carrying the computation result is retrieved and
385 * returned as result.
388 * The order the arguments are given in is important, imagine postfix
390 * Illegal operations will trigger an assertion.
391 * The sort member of the struct mode defines which operations are valid
394 /** bitwise Negation of a tarval. */
395 tarval *tarval_not(tarval *a);
397 /** arithmetic Negation of a tarval. */
398 tarval *tarval_neg(tarval *a);
400 /** Addition of two tarvals. */
401 tarval *tarval_add(tarval *a, tarval *b);
403 /** Subtraction from a tarval. */
404 tarval *tarval_sub(tarval *a, tarval *b);
406 /** Multiplication of tarvals. */
407 tarval *tarval_mul(tarval *a, tarval *b);
409 /** 'Exact' division. */
410 tarval *tarval_quo(tarval *a, tarval *b);
412 /** Integer division. */
413 tarval *tarval_div(tarval *a, tarval *b);
415 /** Remainder of integer division. */
416 tarval *tarval_mod(tarval *a, tarval *b);
418 /** Integer division AND remainder. */
419 tarval *tarval_divmod(tarval *a, tarval *b, tarval **mod_res);
421 /** Absolute value. */
422 tarval *tarval_abs(tarval *a);
425 tarval *tarval_and(tarval *a, tarval *b);
428 tarval *tarval_or(tarval *a, tarval *b);
430 /** Bitwise exclusive or. */
431 tarval *tarval_eor(tarval *a, tarval *b);
434 tarval *tarval_shl(tarval *a, tarval *b);
436 /** Unsigned (logical) right shift. */
437 tarval *tarval_shr(tarval *a, tarval *b);
439 /** Signed (arithmetic) right shift. */
440 tarval *tarval_shrs(tarval *a, tarval *b);
443 tarval *tarval_rot(tarval *a, tarval *b);
445 /** Carry flag of the last operation */
446 int tarval_carry(void);
448 /* *********** Output of tarvals *********** */
451 * The output mode for tarval values.
453 * Some modes allow more that one representation, for instance integers
454 * can be represented hex or decimal. Of course it would be enough to have
455 * one and let every backend convert it into the 'right' one.
456 * However, we can do this in the tarval much simpler...
459 TVO_NATIVE, /**< the default output mode, depends on the mode */
460 TVO_HEX, /**< use hex representation, always possible */
461 TVO_DECIMAL, /**< use decimal representation */
462 TVO_OCTAL, /**< use octal representation */
463 TVO_BINARY, /**< use binary representation */
464 TVO_FLOAT, /**< use floating point representation (i.e 1.342e-2)*/
465 TVO_HEXFLOAT /**< use hexadecimal floating point representation (i.e 0x1.ea32p-12)*/
469 * This structure contains helper information to format the output
470 * of a tarval of a mode.
472 typedef struct tarval_mode_info {
473 tv_output_mode mode_output; /**< if != TVO_NATIVE select a special mode */
474 const char *mode_prefix; /**< if set, this prefix will be printed
475 before a value of this mode */
476 const char *mode_suffix; /**< if set, this suffix will be printed
477 after a value of this mode */
481 * Specify the output options of one mode.
483 * This functions stores the mode info, so DO NOT DESTROY it.
485 * @param mode a ir_mode that should be associated
486 * @param modeinfo the output format info
488 * @return zero on success.
490 int set_tarval_mode_output_option(ir_mode *mode, const tarval_mode_info *modeinfo);
493 * Returns the output options of one mode.
495 * This functions returns the mode info of a given mode.
497 * @param mode a ir_mode that should be associated
499 * @return the output option
501 const tarval_mode_info *get_tarval_mode_output_option(ir_mode *mode);
504 * Returns Bit representation of a tarval value, as string of '0' and '1'
506 * @param tv The tarval
508 * This function returns a printable bit representation of any value
509 * stored as tarval. This representation is a null terminated C string.
512 * As usual in C a pointer to a char is returned. The length of the
513 * returned string if fixed, just read as many chars as the mode defines
517 * The string is allocated using malloc() and is free()ed on the next call
519 * The string consists of the ASCII characters '0' and '1' and is
523 * irmode.h for the definition of the ir_mode struct
524 * the size member of aforementioned struct
526 char *get_tarval_bitpattern(tarval *tv);
529 * Returns the bitpattern of the bytes_ofs byte.
531 * This function succeeds even if the mode of the tarval uses lesser bits
532 * than requested, in that case the bitpattern is filled with zero bits.
534 * To query a 32bit value the following code can be used:
536 * val0 = tarval_sub_bits(tv, 0);
537 * val1 = tarval_sub_bits(tv, 1);
538 * val2 = tarval_sub_bits(tv, 2);
539 * val3 = tarval_sub_bits(tv, 3);
541 * Because this is the bit representation of the target machine, only the following
542 * operations are legal on the result:
544 * - concatenation (endian dependence MUST be handled by the CALLER)
545 * - bitwise logical operations to select/mask bits
547 * @param tv the tarval
548 * @param byte_ofs the byte offset
551 * The result of this function is undefined if the mode is neither integer nor float.
553 unsigned char get_tarval_sub_bits(tarval *tv, unsigned byte_ofs);
556 * Return values of tarval classify
558 typedef enum _tarval_classification_t {
559 TV_CLASSIFY_NULL = 0, /**< the tarval represents the additive neutral element */
560 TV_CLASSIFY_ONE = +1, /**< the tarval represents the multiplicative neutral element */
561 TV_CLASSIFY_ALL_ONE = -1, /**< the tarval represents the bitwise-and neutral element */
562 TV_CLASSIFY_OTHER = 2 /**< all other tarvals */
563 } tarval_classification_t;
566 * Identifying tarvals values for algebraic simplifications.
568 * @param tv the tarval
571 * - TV_CLASSIFY_NULL for additive neutral or the NULL tarval for reference modes,
572 * - TV_CLASSIFY_ONE for multiplicative neutral,
573 * - TV_CLASSIFY_ALL_ONE for bitwise-and neutral
574 * - TV_CLASSIFY_OTHER else
576 tarval_classification_t classify_tarval(tarval *tv);
579 * Returns non-zero if a given (integer) tarval has only one single bit
582 int tarval_is_single_bit(tarval *tv);
585 * Output of tarvals to a buffer.
587 int tarval_snprintf(char *buf, size_t buflen, tarval *tv);
590 * Output of tarvals to stdio.
592 int tarval_printf(tarval *tv);
595 * Returns non-zero if the mantissa of a floating point IEEE-754
596 * tarval is zero (i.e. 1.0Exxx)
598 int tarval_ieee754_zero_mantissa(tarval *tv);
601 * Returns the exponent of a floating point IEEE-754
604 int tarval_ieee754_get_exponent(tarval *tv);
607 * Set the immediate precision for IEEE-754 results. Set this to
608 * 0 to get the same precision as the operands.
609 * For x87 compatibility, set this to 80.
611 * @return the old setting
613 unsigned tarval_ieee754_set_immediate_precision(unsigned bits);
616 * Returns non-zero if the result of the last IEEE-754 operation was exact.
618 unsigned tarval_ieee754_get_exact(void);
621 * Enable/Disable floating point constant folding.
623 int tarval_enable_fp_ops(int enable);
625 #endif /* FIRM_TV_TV_H */