3 * File name: ir/tv/tv.h
4 * Purpose: Representation of and static computations on target machine
10 * Copyright: (c) 2003 Universität Karlsruhe
11 * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
17 * Declarations for Target Values.
28 * tv -- TargetValue, short tarval.
29 * Internal representation for machine values.
35 * Tarvals represent target machine values. They are typed by modes.
36 * Tarvals only represent values of mode_sort:
43 * In case of references the module accepts an entity to represent the
45 * Furthermore, computations and conversions of these values can
49 * This module is closely related to the irmode module, as the modes
50 * defined there are thoroughly used throughout the whole module.
51 * Also, the comparison functions rely on the definition of comparison
52 * values in the irnode module.
55 * The original tv module originated in the fiasco compiler written ...
56 * This is the new version, described in the tech report 1999-14 by ...
60 * irmode.h for the modes definitions
61 * irnode.h for the pn_Cmp table
63 * tarval_init1 and tarval_init2 for initialization of the
68 #ifndef _TARVAL_TYPEDEF_
69 #define _TARVAL_TYPEDEF_
70 typedef struct tarval tarval;
73 /* ************************ Constructors for tarvals ************************ */
76 * Constructor function for new tarvals.
78 * @param str The string representing the target value
79 * @param len The length of the string
80 * @param mode The mode requested for the result tarval
82 * This function creates a new tarval representing the value represented
83 * by a CString, aka char array. If a tarval representing this value already
84 * exists, this tarval is returned instead of a new one. So tarvals are
85 * directly comparable since their representation is unique.
87 * This function accepts the following strings:
89 * if mode is int_number:
90 * - 0(x|X)[0-9a-fA-F]+ (hexadecimal representation)
91 * - 0[0-7]* (octal representation)
92 * - (+|-)?[1-9][0-9]* (decimal representation)
94 * if mode if float_number:
95 * - (+|-)?(decimal int) (. (decimal int))? ((e|E)(+|-)?(decimal int))?
97 * if mode is boolean: true, True, TRUE ... False... 0, 1,
99 * if mode is reference: hexadecimal of decimal number as int
101 * if mode is character: hex or dec
103 * Leading and/or trailing spaces are ignored
106 * A tarval of proper type representing the requested value is returned.
107 * Tarvals are unique, so for any value/mode pair at most one tarval will
108 * exist, which will be returned upon further requests with an identical
112 * If the string is not representable in the given mode an assertion is
113 * thrown in assert build.
116 * irmode.h for predefined modes
117 * new_tarval_from_long()
118 * new_tarval_from_double()
120 tarval *new_tarval_from_str(const char *str, size_t len, ir_mode *mode);
123 * Constructor function for new tarvals
125 * @param l The long representing the value
126 * @param mode The mode requested for the result tarval
128 * This function creates a new tarval representing the value represented
129 * by a long integer. If a tarval representing this value already exists,
130 * this tarval is returned instead of a new one. So tarvals are directly
131 * comparable since their representation is unique.
134 * A tarval of proper type representing the requested value is returned.
135 * Tarvals are unique, so for any value/mode pair at most one tarval will
136 * exist, which will be returned upon further requests with an identical
140 * If the long is not representable in the given mode an assertion is
141 * thrown in assert build.
144 * irmode.h for predefined modes
145 * new_tarval_from_str()
146 * new_tarval_from_double()
149 tarval *new_tarval_from_long(long l, ir_mode *mode);
151 /** Return value as long if possible.
153 * This returns a long int with the value represented value, or
154 * gibberish, depending on the size of long int and the size of the
155 * stored value. It works for e.g. 1 as mode_Ls, but might not work for
156 * get_mode_max(mode_Ls).
157 * This will overflow silently, so use only if you know what
158 * you are doing! (better check with tarval_is_long()...)
159 * Works only for int modes, even not for character modes!
161 long get_tarval_long(tarval *tv);
164 * This validates if get_tarval_long() will return a satisfying
165 * result. I.e. if tv is an int_number and between min, max
166 * of long int (signed!)
168 int tarval_is_long(tarval *tv);
171 * Constructor function for new tarvals.
173 * @param d The (long) double representing the value
174 * @param mode The mode requested for the result tarval
176 * This function creates a new tarval representing the value represented
177 * by a (long) double. If a tarval representing this value already exists,
178 * this tarval is returned instead of a new one. So tarvals are directly
179 * comparable since their representation is unique.
180 * Only modes of sort float_number can be constructed this way.
183 * A tarval of proper type representing the requested value is returned.
184 * Tarvals are unique, so for any value/mode pair at most one tarval will
185 * exist, which will be returned upon further requests with an identical
189 * If the (long) double is not representable in the given mode an assertion
190 * is thrown. This will happen for any mode not of sort float_number.
193 * irmode.h for predefined values
194 * new_tarval_from_str()
195 * new_tarval_from_long()
197 tarval *new_tarval_from_double(long double d, ir_mode *mode);
200 * This returns a double with the value represented value, or
201 * gibberish, depending on the size of double and the size of the
203 * This will overflow silently, so use only if you know what
204 * you are doing! (better check with tarval_is_long...)
206 long double get_tarval_double(tarval *tv);
209 * This validates if tarval_to_double() will return a satisfying
210 * result. I.e. if tv is an float_number and between min, max
213 int tarval_is_double(tarval *tv);
216 /** ********** Access routines for tarval fields ********** **/
224 * ir_mode *get_tarval_mode(tarval *tv)
228 * These are access function for tarval struct members. It is encouraged
229 * to use them instead of direct access to the struct fields.
232 * tv - The tarval to access fields of
235 * get_tv_mode: The mode of the tarval
241 /** Returns the mode of the tarval. */
242 ir_mode *get_tarval_mode (const tarval *tv);
244 /** Returns the contents of the 'link' field of the tarval */
245 /* void *get_tarval_link (tarval*); */
247 /* Testing properties of the represented values */
250 * Returns 1 if tv is negative
252 * @param a the tarval
254 int tarval_is_negative(tarval *a);
257 * Returns 1 if tv is null
259 * @param a the tarval
261 int tarval_is_null(tarval *a);
264 * Returns 1 if tv is the "one"
266 * @param a the tarval
268 int tarval_is_one(tarval *a);
270 /** The 'bad' tarval. */
271 extern tarval *tarval_bad;
272 /** Returns the 'bad tarval. */
273 tarval *get_tarval_bad(void);
275 /** The 'undefined' tarval. */
276 extern tarval *tarval_undefined;
277 /** Returns the 'undefined' tarval. */
278 tarval *get_tarval_undefined(void);
280 /** The mode_b tarval 'false'. */
281 extern tarval *tarval_b_false;
283 /** Returns the mode_b tarval 'false'. */
284 tarval *get_tarval_b_false(void);
286 /** The mode_b tarval 'true'. */
287 extern tarval *tarval_b_true;
288 /** Returns the mode_b tarval 'true'. */
289 tarval *get_tarval_b_true(void);
291 /* These functions calculate and return a tarval representing the requested
293 * The functions get_mode_{Max,Min,...} return tarvals retrieved from these
294 * functions, but these are stored on initialization of the irmode module and
295 * therefore the irmode functions should be preferred to the functions below. */
297 /** Returns the maximum value of a given mode. */
298 tarval *get_tarval_max(ir_mode *mode);
300 /** Returns the minimum value of a given mode. */
301 tarval *get_tarval_min(ir_mode *mode);
303 /** Returns the 0 value (additive neutral) of a given mode.
304 For reference modes, the NULL value is returned (old tarval_P_void) */
305 tarval *get_tarval_null(ir_mode *mode);
307 /** Returns the 1 value (multiplicative neutral) of a given mode. */
308 tarval *get_tarval_one(ir_mode *mode);
310 /** Returns the -1 value (multiplicative neutral) of a given mode.
311 * Returns tarval bad for unsigned modes */
312 tarval *get_tarval_minus_one(ir_mode *mode);
314 /** Return quite nan for float_number modes. */
315 tarval *get_tarval_nan(ir_mode *mode);
317 /** Return +inf for float_number modes. */
318 tarval *get_tarval_plus_inf(ir_mode *mode);
320 /** Return -inf for float_number modes. */
321 tarval *get_tarval_minus_inf(ir_mode *mode);
323 /* ******************** Arithmetic operations on tarvals ******************** */
325 typedef enum _tarval_int_overflow_mode_t {
326 TV_OVERFLOW_BAD, /**< tarval module will return tarval_bad if a overflow occurs */
327 TV_OVERFLOW_WRAP, /**< tarval module will overflow will be ignored, wrap around occurs */
328 TV_OVERFLOW_SATURATE /**< tarval module will saturate the overflow */
329 } tarval_int_overflow_mode_t;
332 * Sets the overflow mode for integer operations.
334 void tarval_set_integer_overflow_mode(tarval_int_overflow_mode_t ov_mode);
337 * Get the overflow mode for integer operations.
339 tarval_int_overflow_mode_t tarval_get_integer_overflow_mode(void);
342 * Compares two tarvals
344 * Compare a with b and return a pn_Cmp describing the relation
345 * between a and b. This is either pn_Cmp_Uo, pn_Cmp_Lt, pn_Cmp_Eq, pn_Cmp_Gt,
346 * or pn_Cmp_False if a or b are symbolic pointers which can not be compared at all.
348 * @param a A tarval to be compared
349 * @param b A tarval to be compared
352 * The pn_Cmp best describing the relation between a and b is returned.
353 * This means the mode with the least bits set is returned, e.g. if the
354 * tarvals are equal the pn_Cmp 'pn_Cmp_Eq' is returned, not 'pn_Cmp_Ge' which
355 * indicates 'greater or equal'
358 * irnode.h for the definition of pn_Cmp
360 pn_Cmp tarval_cmp(tarval *a, tarval *b);
363 * Converts a tarval to another mode.
365 * Convert tarval 'src' to mode 'mode', this will succeed if and only if mode
366 * 'mode' is wider than the mode of src, as defined in the firm documentation
367 * and as returned by the function mode_is_smaller defined in irmode.h.
369 * @param src The tarval to convert
370 * @param mode Tho mode to convert to
373 * If a tarval of mode 'mode' with the result of the conversion of the 'src'
374 * tarvals value already exists, it will be returned, else a new tarval is
375 * constructed and returned
378 * Illegal conversations will trigger an assertion
381 * FIRM documentation for conversion rules
382 * mode_is_smaller defined in irmode.h
384 tarval *tarval_convert_to(tarval *src, ir_mode *mode);
387 * These function implement basic computations representable as opcodes
393 * a - the tarval to operate on
396 * a - the first operand tarval
397 * b - the second operand tarval
400 * If necessary a new tarval is constructed for the resulting value,
401 * or the one already carrying the computation result is retrieved and
402 * returned as result.
405 * The order the arguments are given in is important, imagine postfix
407 * Illegal operations will trigger an assertion.
408 * The sort member of the struct mode defines which operations are valid
411 /** bitwise Negation of a tarval. */
412 tarval *tarval_not(tarval *a);
414 /** arithmetic Negation of a tarval. */
415 tarval *tarval_neg(tarval *a);
417 /** Addition of two tarvals. */
418 tarval *tarval_add(tarval *a, tarval *b);
420 /** Subtraction from a tarval. */
421 tarval *tarval_sub(tarval *a, tarval *b);
423 /** Multiplication of tarvals. */
424 tarval *tarval_mul(tarval *a, tarval *b);
426 /** 'Exact' division. */
427 tarval *tarval_quo(tarval *a, tarval *b);
429 /** Integer division. */
430 tarval *tarval_div(tarval *a, tarval *b);
432 /** Remainder of integer division. */
433 tarval *tarval_mod(tarval *a, tarval *b);
435 /** Absolute value. */
436 tarval *tarval_abs(tarval *a);
439 tarval *tarval_and(tarval *a, tarval *b);
442 tarval *tarval_or(tarval *a, tarval *b);
444 /** Bitwise exclusive or. */
445 tarval *tarval_eor(tarval *a, tarval *b);
448 tarval *tarval_shl(tarval *a, tarval *b);
450 /** Unsigned (logical) right shift. */
451 tarval *tarval_shr(tarval *a, tarval *b);
453 /** Signed (arithmetic) right shift. */
454 tarval *tarval_shrs(tarval *a, tarval *b);
457 tarval *tarval_rot(tarval *a, tarval *b);
459 /** Carry flag of the last operation */
460 int tarval_carry(void);
462 /* *********** Output of tarvals *********** */
465 * The output mode for tarval values.
467 * Some modes allow more that one representation, for instance integers
468 * can be represented hex or decimal. Of course it would be enough to have
469 * one and let every backend convert it into the 'right' one.
470 * However, we can do this in the tarval much simpler...
473 TVO_NATIVE, /**< the default output mode, depends on the mode */
474 TVO_HEX, /**< use hex representation, always possible */
475 TVO_DECIMAL, /**< use decimal representation */
476 TVO_OCTAL, /**< use octal representation */
477 TVO_BINARY, /**< use binary representation */
478 TVO_FLOAT, /**< use floating point representation (i.e 1.342e-2)*/
479 TVO_HEXFLOAT /**< use hexadecimal floating point representation (i.e 0x1.ea32p-12)*/
483 * This structure contains helper information to format the output
484 * of a tarval of a mode.
486 typedef struct tarval_mode_info {
487 tv_output_mode mode_output; /**< if != TVO_NATIVE select a special mode */
488 const char *mode_prefix; /**< if set, this prefix will be printed
489 before a value of this mode */
490 const char *mode_suffix; /**< if set, this suffix will be printed
491 after a value of this mode */
495 * Specify the output options of one mode.
497 * This functions stores the mode info, so DO NOT DESTROY it.
499 * @param mode a ir_mode that should be associated
500 * @param modeinfo the output format info
502 * @return zero on success.
504 int set_tarval_mode_output_option(ir_mode *mode, const tarval_mode_info *modeinfo);
507 * Returns the output options of one mode.
509 * This functions returns the mode info of a given mode.
511 * @param mode a ir_mode that should be associated
513 * @return the output option
515 const tarval_mode_info *get_tarval_mode_output_option(ir_mode *mode);
518 * Returns Bit representation of a tarval value, as string of '0' and '1'
520 * @param tv The tarval
522 * This function returns a printable bit representation of any value
523 * stored as tarval. This representation is a null terminated C string.
526 * As usual in C a pointer to a char is returned. The length of the
527 * returned string if fixed, just read as many chars as the mode defines
531 * The string is allocated using malloc() and is free()ed on the next call
533 * The string consists of the ASCII characters '0' and '1' and is
537 * irmode.h for the definition of the ir_mode struct
538 * the size member of aforementioned struct
540 char *get_tarval_bitpattern(tarval *tv);
543 * Returns the bitpattern of the bytes_ofs byte.
545 * This function succeeds even if the mode of the tarval uses lesser bits
546 * than requested, in that case the bitpattern is filled with zero bits.
548 * To query a 32bit value the following code can be used:
550 * val0 = tarval_sub_bits(tv, 0);
551 * val1 = tarval_sub_bits(tv, 1);
552 * val2 = tarval_sub_bits(tv, 2);
553 * val3 = tarval_sub_bits(tv, 3);
555 * Because this is the bit representation of the target machine, only the following
556 * operations are legal on the result:
558 * - concatenation (endian dependence MUST be handled by the CALLER)
559 * - bitwise logical operations to select/mask bits
561 * @param tv the tarval
562 * @param byte_ofs the byte offset
565 * The result of this function is undefined if the mode is neither integer nor float.
567 unsigned char get_tarval_sub_bits(tarval *tv, unsigned byte_ofs);
570 * Return values of tarval classify
572 typedef enum _tarval_classification_t {
573 TV_CLASSIFY_NULL = 0, /**< the tarval represents the additive neutral element */
574 TV_CLASSIFY_ONE = +1, /**< the tarval represents the multiplicative neutral element */
575 TV_CLASSIFY_ALL_ONE = -1, /**< the tarval represents the bitwise-and neutral element */
576 TV_CLASSIFY_OTHER = 2 /**< all other tarvals */
577 } tarval_classification_t;
580 * Identifying tarvals values for algebraic simplifications.
582 * @param tv the tarval
585 * - TV_CLASSIFY_NULL for additive neutral or the NULL tarval for reference modes,
586 * - TV_CLASSIFY_ONE for multiplicative neutral,
587 * - TV_CLASSIFY_ALL_ONE for bitwise-and neutral
588 * - TV_CLASSIFY_OTHER else
590 tarval_classification_t classify_tarval(tarval *tv);
593 * Returns non-zero if a given (integer) tarval has only one single bit
596 int is_single_bit_tarval(tarval *tv);
599 * Output of tarvals to a buffer.
601 int tarval_snprintf(char *buf, size_t buflen, tarval *tv);
604 * Output of tarvals to stdio.
606 int tarval_printf(tarval *tv);