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 /** The 'void' pointer tarval. */
292 extern tarval *tarval_P_void;
293 /** Returns the 'void' pointer tarval. */
294 tarval *get_tarval_P_void(void);
296 /* These functions calculate and return a tarval representing the requested
298 * The functions get_mode_{Max,Min,...} return tarvals retrieved from these
299 * functions, but these are stored on initialization of the irmode module and
300 * therefore the irmode functions should be prefered to the functions below. */
302 /** Returns the maximum value of a given mode. */
303 tarval *get_tarval_max(ir_mode *mode);
305 /** Returns the minimum value of a given mode. */
306 tarval *get_tarval_min(ir_mode *mode);
308 /** Returns the 0 value (additive neutral) of a given mode. */
309 tarval *get_tarval_null(ir_mode *mode);
311 /** Returns the 1 value (multiplicative neutral) of a given mode. */
312 tarval *get_tarval_one(ir_mode *mode);
314 /** Returns the -1 value (multiplicative neutral) of a given mode.
315 * Returns tarval bad for unsigned modes */
316 tarval *get_tarval_minus_one(ir_mode *mode);
318 /** Return quite nan for float_number modes. */
319 tarval *get_tarval_nan(ir_mode *mode);
321 /** Return +inf for float_number modes. */
322 tarval *get_tarval_plus_inf(ir_mode *mode);
324 /** Return -inf for float_number modes. */
325 tarval *get_tarval_minus_inf(ir_mode *mode);
327 /* ******************** Arithmetic operations on tarvals ******************** */
329 typedef enum _tarval_int_overflow_mode_t {
330 TV_OVERFLOW_BAD, /**< tarval module will return tarval_bad if a overflow occurs */
331 TV_OVERFLOW_WRAP, /**< tarval module will overflow will be ignored, wrap around occurs */
332 TV_OVERFLOW_SATURATE /**< tarval module will saturate the overflow */
333 } tarval_int_overflow_mode_t;
336 * Sets the overflow mode for integer operations.
338 void tarval_set_integer_overflow_mode(tarval_int_overflow_mode_t ov_mode);
341 * Get the overflow mode for integer operations.
343 tarval_int_overflow_mode_t tarval_get_integer_overflow_mode(void);
346 * Compares two tarvals
348 * Compare a with b and return a pn_Cmp describing the relation
349 * between a and b. This is either pn_Cmp_Uo, pn_Cmp_Lt, pn_Cmp_Eq, pn_Cmp_Gt,
350 * or pn_Cmp_False if a or b are symbolic pointers which can not be compared at all.
352 * @param a A tarval to be compared
353 * @param b A tarval to be compared
356 * The pn_Cmp best describing the relation between a and b is returned.
357 * This means the mode with the least bits set is returned, e.g. if the
358 * tarvals are equal the pn_Cmp 'pn_Cmp_Eq' is returned, not 'pn_Cmp_Ge' which
359 * indicates 'greater or equal'
362 * irnode.h for the definition of pn_Cmp
364 pn_Cmp tarval_cmp(tarval *a, tarval *b);
367 * Converts a tarval to another mode.
369 * Convert tarval 'src' to mode 'mode', this will succeed if and only if mode
370 * 'mode' is wider than the mode of src, as defined in the firm documentation
371 * and as returned by the function mode_is_smaller defined in irmode.h.
373 * @param src The tarval to convert
374 * @param mode Tho mode to convert to
377 * If a tarval of mode 'mode' with the result of the conversion of the 'src'
378 * tarvals value already exists, it will be returned, else a new tarval is
379 * constructed and returned
382 * Illegal conversations will trigger an assertion
385 * FIRM documentation for conversion rules
386 * mode_is_smaller defined in irmode.h
388 tarval *tarval_convert_to(tarval *src, ir_mode *mode);
391 * These function implement basic computations representable as opcodes
397 * a - the tarval to operate on
400 * a - the first operand tarval
401 * b - the second operand tarval
404 * If necessary a new tarval is constructed for the resulting value,
405 * or the one already carrying the computation result is retrieved and
406 * returned as result.
409 * The order the arguments are given in is important, imagine postfix
411 * Illegal operations will trigger an assertion.
412 * The sort member of the struct mode defines which operations are valid
415 /** bitwise Negation of a tarval. */
416 tarval *tarval_not(tarval *a);
418 /** arithmetic Negation of a tarval. */
419 tarval *tarval_neg(tarval *a);
421 /** Addition of two tarvals. */
422 tarval *tarval_add(tarval *a, tarval *b);
424 /** Subtraction from a tarval. */
425 tarval *tarval_sub(tarval *a, tarval *b);
427 /** Multiplication of tarvals. */
428 tarval *tarval_mul(tarval *a, tarval *b);
430 /** 'Exact' division. */
431 tarval *tarval_quo(tarval *a, tarval *b);
433 /** Integer division. */
434 tarval *tarval_div(tarval *a, tarval *b);
436 /** Remainder of integer division. */
437 tarval *tarval_mod(tarval *a, tarval *b);
439 /** Absolute value. */
440 tarval *tarval_abs(tarval *a);
443 tarval *tarval_and(tarval *a, tarval *b);
446 tarval *tarval_or(tarval *a, tarval *b);
448 /** Bitwise exclusive or. */
449 tarval *tarval_eor(tarval *a, tarval *b);
452 tarval *tarval_shl(tarval *a, tarval *b);
454 /** Unsigned (logical) right shift. */
455 tarval *tarval_shr(tarval *a, tarval *b);
457 /** Signed (arithmetic) right shift. */
458 tarval *tarval_shrs(tarval *a, tarval *b);
461 tarval *tarval_rot(tarval *a, tarval *b);
463 /** Carry flag of the last operation */
464 int tarval_carry(void);
466 /* *********** Output of tarvals *********** */
469 * The output mode for tarval values.
471 * Some modes allow more that one representation, for instance integers
472 * can be represented hex or decimal. Of course it would be enough to have
473 * one and let every backend convert it into the 'right' one.
474 * However, we can do this in the tarval much simpler...
477 TVO_NATIVE, /**< the default output mode, depends on the mode */
478 TVO_HEX, /**< use hex representation, always possible */
479 TVO_DECIMAL, /**< use decimal representation */
480 TVO_OCTAL, /**< use octal representation */
481 TVO_BINARY, /**< use binary representation */
482 TVO_FLOAT, /**< use floating point representation (i.e 1.342e-2)*/
483 TVO_HEXFLOAT /**< use hexadecimal floating point representation (i.e 0x1.ea32p-12)*/
487 * This structure contains helper information to format the output
488 * of a tarval of a mode.
490 typedef struct tarval_mode_info {
491 tv_output_mode mode_output; /**< if != TVO_NATIVE select a special mode */
492 const char *mode_prefix; /**< if set, this prefix will be printed
493 before a value of this mode */
494 const char *mode_suffix; /**< if set, this suffix will be printed
495 after a value of this mode */
499 * Specify the output options of one mode.
501 * This functions stores the mode info, so DO NOT DESTROY it.
503 * @param mode a ir_mode that should be associated
504 * @param modeinfo the output format info
506 * @return zero on success.
508 int set_tarval_mode_output_option(ir_mode *mode, const tarval_mode_info *modeinfo);
511 * Returns the output options of one mode.
513 * This functions returns the mode info of a given mode.
515 * @param mode a ir_mode that should be associated
517 * @return the output option
519 const tarval_mode_info *get_tarval_mode_output_option(ir_mode *mode);
522 * Returns Bit representation of a tarval value, as string of '0' and '1'
524 * @param tv The tarval
526 * This function returns a printable bit representation of any value
527 * stored as tarval. This representation is a null terminated C string.
530 * As usual in C a pointer to a char is returned. The length of the
531 * returned string if fixed, just read as many chars as the mode defines
535 * The string is allocated using malloc() and is free()ed on the next call
537 * The string consists of the ASCII characters '0' and '1' and is
541 * irmode.h for the definition of the ir_mode struct
542 * the size member of aforementioned struct
544 char *get_tarval_bitpattern(tarval *tv);
547 * Returns the bitpattern of the bytes_ofs byte.
549 * This function succeeds even if the mode of the tarval uses lesser bits
550 * than requested, in that case the bitpattern is filled with zero bits.
552 * To query a 32bit value the following code can be used:
554 * val0 = tarval_sub_bits(tv, 0);
555 * val1 = tarval_sub_bits(tv, 1);
556 * val2 = tarval_sub_bits(tv, 2);
557 * val3 = tarval_sub_bits(tv, 3);
559 * Because this is the bit representation of the target machine, only the following
560 * operations are legal on the result:
562 * - concatenation (endian dependence MUST be handled by the CALLER)
563 * - bitwise logical operations to select/mask bits
565 * @param tv the tarval
566 * @param byte_ofs the byte offset
569 * The result of this function is undefined if the mode is neither integer nor float.
571 unsigned char get_tarval_sub_bits(tarval *tv, unsigned byte_ofs);
574 * Return values of tarval classify
576 typedef enum _tarval_classification_t {
577 TV_CLASSIFY_NULL = 0, /**< the tarval represents the additive neutral element */
578 TV_CLASSIFY_ONE = +1, /**< the tarval represents the multiplicative neutral element */
579 TV_CLASSIFY_ALL_ONE = -1, /**< the tarval represents the bitwise-and neutral element */
580 TV_CLASSIFY_OTHER = 2 /**< all other tarvals */
581 } tarval_classification_t;
584 * Identifying tarvals values for algebraic simplifications.
587 * - TV_CLASSIFY_NULL for additive neutral,
588 * - TV_CLASSIFY_ONE for multiplicative neutral,
589 * - TV_CLASSIFY_ALL_ONE for bitwise-and neutral
590 * - TV_CLASSIFY_OTHER else
592 tarval_classification_t classify_tarval(tarval *tv);
595 * Output of tarvals to a buffer.
597 int tarval_snprintf(char *buf, size_t buflen, tarval *tv);
600 * Output of tarvals to stdio.
602 int tarval_printf(tarval *tv);