1 //===-- llvm/Support/APInt.h - For Arbitrary Precision Integer -*- C++ -*--===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by Sheng Zhou and is distributed under the
6 // University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements a class to represent arbitrary precision integral
11 // constant values and operations on them.
13 //===----------------------------------------------------------------------===//
18 #include "llvm/Support/DataTypes.h"
24 //===----------------------------------------------------------------------===//
26 //===----------------------------------------------------------------------===//
28 /// APInt - This class represents arbitrary precision constant integral values.
29 /// It is a functional replacement for common case unsigned integer type like
30 /// "unsigned", "unsigned long" or "uint64_t", but also allows non-byte-width
31 /// integer sizes and large integer value types such as 3-bits, 15-bits, or more
32 /// than 64-bits of precision. APInt provides a variety of arithmetic operators
33 /// and methods to manipulate integer values of any bit-width. It supports both
34 /// the typical integer arithmetic and comparison operations as well as bitwise
37 /// The class has several invariants worth noting:
38 /// * All bit, byte, and word positions are zero-based.
39 /// * Once the bit width is set, it doesn't change except by the Truncate,
40 /// SignExtend, or ZeroExtend operations.
41 /// * All binary operators must be on APInt instances of the same bit width.
42 /// Attempting to use these operators on instances with different bit
43 /// widths will yield an assertion.
44 /// * The value is stored canonically as an unsigned value. For operations
45 /// where it makes a difference, there are both signed and unsigned variants
46 /// of the operation. For example, sdiv and udiv. However, because the bit
47 /// widths must be the same, operations such as Mul and Add produce the same
48 /// results regardless of whether the values are interpreted as signed or
50 /// * In general, the class tries to follow the style of computation that LLVM
51 /// uses in its IR. This simplifies its use for LLVM.
53 /// @brief Class for arbitrary precision integers.
56 uint32_t BitWidth; ///< The number of bits in this APInt.
58 /// This union is used to store the integer value. When the
59 /// integer bit-width <= 64, it uses VAL, otherwise it uses pVal.
61 uint64_t VAL; ///< Used to store the <= 64 bits integer value.
62 uint64_t *pVal; ///< Used to store the >64 bits integer value.
65 /// This enum is used to hold the constants we needed for APInt.
67 APINT_BITS_PER_WORD = sizeof(uint64_t) * 8, ///< Bits in a word
68 APINT_WORD_SIZE = sizeof(uint64_t) ///< Byte size of a word
71 /// This constructor is used only internally for speed of construction of
72 /// temporaries. It is unsafe for general use so it is not public.
73 /// @brief Fast internal constructor
74 APInt(uint64_t* val, uint32_t bits) : BitWidth(bits), pVal(val) { }
76 /// @returns true if the number of bits <= 64, false otherwise.
77 /// @brief Determine if this APInt just has one word to store value.
78 inline bool isSingleWord() const {
79 return BitWidth <= APINT_BITS_PER_WORD;
82 /// @returns the word position for the specified bit position.
83 /// @brief Determine which word a bit is in.
84 static inline uint32_t whichWord(uint32_t bitPosition) {
85 return bitPosition / APINT_BITS_PER_WORD;
88 /// @returns the bit position in a word for the specified bit position
90 /// @brief Determine which bit in a word a bit is in.
91 static inline uint32_t whichBit(uint32_t bitPosition) {
92 return bitPosition % APINT_BITS_PER_WORD;
95 /// This method generates and returns a uint64_t (word) mask for a single
96 /// bit at a specific bit position. This is used to mask the bit in the
97 /// corresponding word.
98 /// @returns a uint64_t with only bit at "whichBit(bitPosition)" set
99 /// @brief Get a single bit mask.
100 static inline uint64_t maskBit(uint32_t bitPosition) {
101 return 1ULL << whichBit(bitPosition);
104 /// This method is used internally to clear the to "N" bits in the high order
105 /// word that are not used by the APInt. This is needed after the most
106 /// significant word is assigned a value to ensure that those bits are
108 /// @brief Clear unused high order bits
109 inline APInt& clearUnusedBits() {
110 // Compute how many bits are used in the final word
111 uint32_t wordBits = BitWidth % APINT_BITS_PER_WORD;
113 // If all bits are used, we want to leave the value alone. This also
114 // avoids the undefined behavior of >> when the shfit is the same size as
115 // the word size (64).
118 // Mask out the hight bits.
119 uint64_t mask = ~uint64_t(0ULL) >> (APINT_BITS_PER_WORD - wordBits);
123 pVal[getNumWords() - 1] &= mask;
127 /// @returns the corresponding word for the specified bit position.
128 /// @brief Get the word corresponding to a bit position
129 inline uint64_t getWord(uint32_t bitPosition) const {
130 return isSingleWord() ? VAL : pVal[whichWord(bitPosition)];
133 /// This is used by the constructors that take string arguments.
134 /// @brief Convert a char array into an APInt
135 void fromString(uint32_t numBits, const char *strStart, uint32_t slen,
138 /// This is used by the toString method to divide by the radix. It simply
139 /// provides a more convenient form of divide for internal use since KnuthDiv
140 /// has specific constraints on its inputs. If those constraints are not met
141 /// then it provides a simpler form of divide.
142 /// @brief An internal division function for dividing APInts.
143 static void divide(const APInt LHS, uint32_t lhsWords,
144 const APInt &RHS, uint32_t rhsWords,
145 APInt *Quotient, APInt *Remainder);
148 /// @brief debug method
153 /// @name Constructors
155 /// If isSigned is true then val is treated as if it were a signed value
156 /// (i.e. as an int64_t) and the appropriate sign extension to the bit width
157 /// will be done. Otherwise, no sign extension occurs (high order bits beyond
158 /// the range of val are zero filled).
159 /// @param numBits the bit width of the constructed APInt
160 /// @param val the initial value of the APInt
161 /// @param isSigned how to treat signedness of val
162 /// @brief Create a new APInt of numBits width, initialized as val.
163 APInt(uint32_t numBits, uint64_t val, bool isSigned = false);
165 /// Note that numWords can be smaller or larger than the corresponding bit
166 /// width but any extraneous bits will be dropped.
167 /// @param numBits the bit width of the constructed APInt
168 /// @param numWords the number of words in bigVal
169 /// @param bigVal a sequence of words to form the initial value of the APInt
170 /// @brief Construct an APInt of numBits width, initialized as bigVal[].
171 APInt(uint32_t numBits, uint32_t numWords, uint64_t bigVal[]);
173 /// This constructor interprets Val as a string in the given radix. The
174 /// interpretation stops when the first charater that is not suitable for the
175 /// radix is encountered. Acceptable radix values are 2, 8, 10 and 16. It is
176 /// an error for the value implied by the string to require more bits than
178 /// @param numBits the bit width of the constructed APInt
179 /// @param val the string to be interpreted
180 /// @param radix the radix of Val to use for the intepretation
181 /// @brief Construct an APInt from a string representation.
182 APInt(uint32_t numBits, const std::string& val, uint8_t radix);
184 /// This constructor interprets the slen characters starting at StrStart as
185 /// a string in the given radix. The interpretation stops when the first
186 /// character that is not suitable for the radix is encountered. Acceptable
187 /// radix values are 2, 8, 10 and 16. It is an error for the value implied by
188 /// the string to require more bits than numBits.
189 /// @param numBits the bit width of the constructed APInt
190 /// @param strStart the start of the string to be interpreted
191 /// @param slen the maximum number of characters to interpret
192 /// @brief Construct an APInt from a string representation.
193 APInt(uint32_t numBits, const char strStart[], uint32_t slen, uint8_t radix);
195 /// Simply makes *this a copy of that.
196 /// @brief Copy Constructor.
197 APInt(const APInt& that);
199 /// @brief Destructor.
203 /// @name Value Tests
205 /// This tests the high bit of this APInt to determine if it is set.
206 /// @returns true if this APInt is negative, false otherwise
207 /// @brief Determine sign of this APInt.
208 bool isNegative() const {
209 return (*this)[BitWidth - 1];
212 /// This tests the high bit of the APInt to determine if it is unset.
213 /// @brief Determine if this APInt Value is positive (not negative).
214 bool isPositive() const {
215 return !isNegative();
218 /// This tests if the value of this APInt is strictly positive (> 0).
219 /// @returns true if this APInt is Positive and not zero.
220 /// @brief Determine if this APInt Value is strictly positive.
221 inline bool isStrictlyPositive() const {
222 return isPositive() && (*this) != 0;
225 /// This checks to see if the value has all bits of the APInt are set or not.
226 /// @brief Determine if all bits are set
227 inline bool isAllOnesValue() const {
228 return countPopulation() == BitWidth;
231 /// This checks to see if the value of this APInt is the maximum unsigned
232 /// value for the APInt's bit width.
233 /// @brief Determine if this is the largest unsigned value.
234 bool isMaxValue() const {
235 return countPopulation() == BitWidth;
238 /// This checks to see if the value of this APInt is the maximum signed
239 /// value for the APInt's bit width.
240 /// @brief Determine if this is the largest signed value.
241 bool isMaxSignedValue() const {
242 return BitWidth == 1 ? VAL == 0 :
243 !isNegative() && countPopulation() == BitWidth - 1;
246 /// This checks to see if the value of this APInt is the minimum unsigned
247 /// value for the APInt's bit width.
248 /// @brief Determine if this is the smallest unsigned value.
249 bool isMinValue() const {
250 return countPopulation() == 0;
253 /// This checks to see if the value of this APInt is the minimum signed
254 /// value for the APInt's bit width.
255 /// @brief Determine if this is the smallest signed value.
256 bool isMinSignedValue() const {
257 return BitWidth == 1 ? VAL == 1 :
258 isNegative() && countPopulation() == 1;
261 /// @brief Check if this APInt has an N-bits integer value.
262 inline bool isIntN(uint32_t N) const {
263 assert(N && "N == 0 ???");
264 if (isSingleWord()) {
265 return VAL == (VAL & (~0ULL >> (64 - N)));
267 APInt Tmp(N, getNumWords(), pVal);
268 return Tmp == (*this);
272 /// @returns true if the argument APInt value is a power of two > 0.
273 bool isPowerOf2() const;
275 /// isSignBit - Return true if this is the value returned by getSignBit.
276 bool isSignBit() const { return isMinSignedValue(); }
278 /// This converts the APInt to a boolean value as a test against zero.
279 /// @brief Boolean conversion function.
280 inline bool getBoolValue() const {
281 return countLeadingZeros() != BitWidth;
285 /// @name Value Generators
287 /// @brief Gets maximum unsigned value of APInt for specific bit width.
288 static APInt getMaxValue(uint32_t numBits) {
289 return APInt(numBits, 0).set();
292 /// @brief Gets maximum signed value of APInt for a specific bit width.
293 static APInt getSignedMaxValue(uint32_t numBits) {
294 return APInt(numBits, 0).set().clear(numBits - 1);
297 /// @brief Gets minimum unsigned value of APInt for a specific bit width.
298 static APInt getMinValue(uint32_t numBits) {
299 return APInt(numBits, 0);
302 /// @brief Gets minimum signed value of APInt for a specific bit width.
303 static APInt getSignedMinValue(uint32_t numBits) {
304 return APInt(numBits, 0).set(numBits - 1);
307 /// getSignBit - This is just a wrapper function of getSignedMinValue(), and
308 /// it helps code readability when we want to get a SignBit.
309 /// @brief Get the SignBit for a specific bit width.
310 inline static APInt getSignBit(uint32_t BitWidth) {
311 return getSignedMinValue(BitWidth);
314 /// @returns the all-ones value for an APInt of the specified bit-width.
315 /// @brief Get the all-ones value.
316 static APInt getAllOnesValue(uint32_t numBits) {
317 return APInt(numBits, 0).set();
320 /// @returns the '0' value for an APInt of the specified bit-width.
321 /// @brief Get the '0' value.
322 static APInt getNullValue(uint32_t numBits) {
323 return APInt(numBits, 0);
326 /// Get an APInt with the same BitWidth as this APInt, just zero mask
327 /// the low bits and right shift to the least significant bit.
328 /// @returns the high "numBits" bits of this APInt.
329 APInt getHiBits(uint32_t numBits) const;
331 /// Get an APInt with the same BitWidth as this APInt, just zero mask
333 /// @returns the low "numBits" bits of this APInt.
334 APInt getLoBits(uint32_t numBits) const;
336 /// Constructs an APInt value that has a contiguous range of bits set. The
337 /// bits from loBit to hiBit will be set. All other bits will be zero. For
338 /// example, with parameters(32, 15, 0) you would get 0x0000FFFF. If hiBit is
339 /// less than loBit then the set bits "wrap". For example, with
340 /// parameters (32, 3, 28), you would get 0xF000000F.
341 /// @param numBits the intended bit width of the result
342 /// @param loBit the index of the lowest bit set.
343 /// @param hiBit the index of the highest bit set.
344 /// @returns An APInt value with the requested bits set.
345 /// @brief Get a value with a block of bits set.
346 static APInt getBitsSet(uint32_t numBits, uint32_t loBit, uint32_t hiBit) {
347 assert(hiBit < numBits && "hiBit out of range");
348 assert(loBit < numBits && "loBit out of range");
350 return getLowBitsSet(numBits, hiBit+1) |
351 getHighBitsSet(numBits, numBits-loBit+1);
352 return getLowBitsSet(numBits, hiBit-loBit+1).shl(loBit);
355 /// Constructs an APInt value that has the top hiBitsSet bits set.
356 /// @param numBits the bitwidth of the result
357 /// @param hiBitsSet the number of high-order bits set in the result.
358 /// @brief Get a value with high bits set
359 static APInt getHighBitsSet(uint32_t numBits, uint32_t hiBitsSet) {
360 assert(hiBitsSet <= numBits && "Too many bits to set!");
361 // Handle a degenerate case, to avoid shifting by word size
363 return APInt(numBits, 0);
364 uint32_t shiftAmt = numBits - hiBitsSet;
365 // For small values, return quickly
366 if (numBits <= APINT_BITS_PER_WORD)
367 return APInt(numBits, ~0ULL << shiftAmt);
368 return (~APInt(numBits, 0)).shl(shiftAmt);
371 /// Constructs an APInt value that has the bottom loBitsSet bits set.
372 /// @param numBits the bitwidth of the result
373 /// @param loBitsSet the number of low-order bits set in the result.
374 /// @brief Get a value with low bits set
375 static APInt getLowBitsSet(uint32_t numBits, uint32_t loBitsSet) {
376 assert(loBitsSet <= numBits && "Too many bits to set!");
377 // Handle a degenerate case, to avoid shifting by word size
379 return APInt(numBits, 0);
380 if (loBitsSet == APINT_BITS_PER_WORD)
381 return APInt(numBits, -1ULL);
382 // For small values, return quickly
383 if (numBits < APINT_BITS_PER_WORD)
384 return APInt(numBits, (1ULL << loBitsSet) - 1);
385 return (~APInt(numBits, 0)).lshr(numBits - loBitsSet);
388 /// The hash value is computed as the sum of the words and the bit width.
389 /// @returns A hash value computed from the sum of the APInt words.
390 /// @brief Get a hash value based on this APInt
391 uint64_t getHashValue() const;
393 /// This function returns a pointer to the internal storage of the APInt.
394 /// This is useful for writing out the APInt in binary form without any
396 inline const uint64_t* getRawData() const {
403 /// @name Unary Operators
405 /// @returns a new APInt value representing *this incremented by one
406 /// @brief Postfix increment operator.
407 inline const APInt operator++(int) {
413 /// @returns *this incremented by one
414 /// @brief Prefix increment operator.
417 /// @returns a new APInt representing *this decremented by one.
418 /// @brief Postfix decrement operator.
419 inline const APInt operator--(int) {
425 /// @returns *this decremented by one.
426 /// @brief Prefix decrement operator.
429 /// Performs a bitwise complement operation on this APInt.
430 /// @returns an APInt that is the bitwise complement of *this
431 /// @brief Unary bitwise complement operator.
432 APInt operator~() const;
434 /// Negates *this using two's complement logic.
435 /// @returns An APInt value representing the negation of *this.
436 /// @brief Unary negation operator
437 inline APInt operator-() const {
438 return APInt(BitWidth, 0) - (*this);
441 /// Performs logical negation operation on this APInt.
442 /// @returns true if *this is zero, false otherwise.
443 /// @brief Logical negation operator.
444 bool operator !() const;
447 /// @name Assignment Operators
449 /// @returns *this after assignment of RHS.
450 /// @brief Copy assignment operator.
451 APInt& operator=(const APInt& RHS);
453 /// The RHS value is assigned to *this. If the significant bits in RHS exceed
454 /// the bit width, the excess bits are truncated. If the bit width is larger
455 /// than 64, the value is zero filled in the unspecified high order bits.
456 /// @returns *this after assignment of RHS value.
457 /// @brief Assignment operator.
458 APInt& operator=(uint64_t RHS);
460 /// Performs a bitwise AND operation on this APInt and RHS. The result is
461 /// assigned to *this.
462 /// @returns *this after ANDing with RHS.
463 /// @brief Bitwise AND assignment operator.
464 APInt& operator&=(const APInt& RHS);
466 /// Performs a bitwise OR operation on this APInt and RHS. The result is
468 /// @returns *this after ORing with RHS.
469 /// @brief Bitwise OR assignment operator.
470 APInt& operator|=(const APInt& RHS);
472 /// Performs a bitwise XOR operation on this APInt and RHS. The result is
473 /// assigned to *this.
474 /// @returns *this after XORing with RHS.
475 /// @brief Bitwise XOR assignment operator.
476 APInt& operator^=(const APInt& RHS);
478 /// Multiplies this APInt by RHS and assigns the result to *this.
480 /// @brief Multiplication assignment operator.
481 APInt& operator*=(const APInt& RHS);
483 /// Adds RHS to *this and assigns the result to *this.
485 /// @brief Addition assignment operator.
486 APInt& operator+=(const APInt& RHS);
488 /// Subtracts RHS from *this and assigns the result to *this.
490 /// @brief Subtraction assignment operator.
491 APInt& operator-=(const APInt& RHS);
493 /// Shifts *this left by shiftAmt and assigns the result to *this.
494 /// @returns *this after shifting left by shiftAmt
495 /// @brief Left-shift assignment function.
496 inline APInt& operator<<=(uint32_t shiftAmt) {
497 *this = shl(shiftAmt);
502 /// @name Binary Operators
504 /// Performs a bitwise AND operation on *this and RHS.
505 /// @returns An APInt value representing the bitwise AND of *this and RHS.
506 /// @brief Bitwise AND operator.
507 APInt operator&(const APInt& RHS) const;
508 APInt And(const APInt& RHS) const {
509 return this->operator&(RHS);
512 /// Performs a bitwise OR operation on *this and RHS.
513 /// @returns An APInt value representing the bitwise OR of *this and RHS.
514 /// @brief Bitwise OR operator.
515 APInt operator|(const APInt& RHS) const;
516 APInt Or(const APInt& RHS) const {
517 return this->operator|(RHS);
520 /// Performs a bitwise XOR operation on *this and RHS.
521 /// @returns An APInt value representing the bitwise XOR of *this and RHS.
522 /// @brief Bitwise XOR operator.
523 APInt operator^(const APInt& RHS) const;
524 APInt Xor(const APInt& RHS) const {
525 return this->operator^(RHS);
528 /// Multiplies this APInt by RHS and returns the result.
529 /// @brief Multiplication operator.
530 APInt operator*(const APInt& RHS) const;
532 /// Adds RHS to this APInt and returns the result.
533 /// @brief Addition operator.
534 APInt operator+(const APInt& RHS) const;
535 APInt operator+(uint64_t RHS) const {
536 return (*this) + APInt(BitWidth, RHS);
539 /// Subtracts RHS from this APInt and returns the result.
540 /// @brief Subtraction operator.
541 APInt operator-(const APInt& RHS) const;
542 APInt operator-(uint64_t RHS) const {
543 return (*this) - APInt(BitWidth, RHS);
546 /// Arithmetic right-shift this APInt by shiftAmt.
547 /// @brief Arithmetic right-shift function.
548 APInt ashr(uint32_t shiftAmt) const;
550 /// Logical right-shift this APInt by shiftAmt.
551 /// @brief Logical right-shift function.
552 APInt lshr(uint32_t shiftAmt) const;
554 /// Left-shift this APInt by shiftAmt.
555 /// @brief Left-shift function.
556 APInt shl(uint32_t shiftAmt) const;
558 /// Perform an unsigned divide operation on this APInt by RHS. Both this and
559 /// RHS are treated as unsigned quantities for purposes of this division.
560 /// @returns a new APInt value containing the division result
561 /// @brief Unsigned division operation.
562 APInt udiv(const APInt& RHS) const;
564 /// Signed divide this APInt by APInt RHS.
565 /// @brief Signed division function for APInt.
566 inline APInt sdiv(const APInt& RHS) const {
568 if (RHS.isNegative())
569 return (-(*this)).udiv(-RHS);
571 return -((-(*this)).udiv(RHS));
572 else if (RHS.isNegative())
573 return -(this->udiv(-RHS));
574 return this->udiv(RHS);
577 /// Perform an unsigned remainder operation on this APInt with RHS being the
578 /// divisor. Both this and RHS are treated as unsigned quantities for purposes
579 /// of this operation. Note that this is a true remainder operation and not
580 /// a modulo operation because the sign follows the sign of the dividend
582 /// @returns a new APInt value containing the remainder result
583 /// @brief Unsigned remainder operation.
584 APInt urem(const APInt& RHS) const;
586 /// Signed remainder operation on APInt.
587 /// @brief Function for signed remainder operation.
588 inline APInt srem(const APInt& RHS) const {
590 if (RHS.isNegative())
591 return -((-(*this)).urem(-RHS));
593 return -((-(*this)).urem(RHS));
594 else if (RHS.isNegative())
595 return this->urem(-RHS);
596 return this->urem(RHS);
599 /// @returns the bit value at bitPosition
600 /// @brief Array-indexing support.
601 bool operator[](uint32_t bitPosition) const;
604 /// @name Comparison Operators
606 /// Compares this APInt with RHS for the validity of the equality
608 /// @brief Equality operator.
609 bool operator==(const APInt& RHS) const;
611 /// Compares this APInt with a uint64_t for the validity of the equality
613 /// @returns true if *this == Val
614 /// @brief Equality operator.
615 bool operator==(uint64_t Val) const;
617 /// Compares this APInt with RHS for the validity of the equality
619 /// @returns true if *this == Val
620 /// @brief Equality comparison.
621 bool eq(const APInt &RHS) const {
622 return (*this) == RHS;
625 /// Compares this APInt with RHS for the validity of the inequality
627 /// @returns true if *this != Val
628 /// @brief Inequality operator.
629 inline bool operator!=(const APInt& RHS) const {
630 return !((*this) == RHS);
633 /// Compares this APInt with a uint64_t for the validity of the inequality
635 /// @returns true if *this != Val
636 /// @brief Inequality operator.
637 inline bool operator!=(uint64_t Val) const {
638 return !((*this) == Val);
641 /// Compares this APInt with RHS for the validity of the inequality
643 /// @returns true if *this != Val
644 /// @brief Inequality comparison
645 bool ne(const APInt &RHS) const {
646 return !((*this) == RHS);
649 /// Regards both *this and RHS as unsigned quantities and compares them for
650 /// the validity of the less-than relationship.
651 /// @returns true if *this < RHS when both are considered unsigned.
652 /// @brief Unsigned less than comparison
653 bool ult(const APInt& RHS) const;
655 /// Regards both *this and RHS as signed quantities and compares them for
656 /// validity of the less-than relationship.
657 /// @returns true if *this < RHS when both are considered signed.
658 /// @brief Signed less than comparison
659 bool slt(const APInt& RHS) const;
661 /// Regards both *this and RHS as unsigned quantities and compares them for
662 /// validity of the less-or-equal relationship.
663 /// @returns true if *this <= RHS when both are considered unsigned.
664 /// @brief Unsigned less or equal comparison
665 bool ule(const APInt& RHS) const {
666 return ult(RHS) || eq(RHS);
669 /// Regards both *this and RHS as signed quantities and compares them for
670 /// validity of the less-or-equal relationship.
671 /// @returns true if *this <= RHS when both are considered signed.
672 /// @brief Signed less or equal comparison
673 bool sle(const APInt& RHS) const {
674 return slt(RHS) || eq(RHS);
677 /// Regards both *this and RHS as unsigned quantities and compares them for
678 /// the validity of the greater-than relationship.
679 /// @returns true if *this > RHS when both are considered unsigned.
680 /// @brief Unsigned greather than comparison
681 bool ugt(const APInt& RHS) const {
682 return !ult(RHS) && !eq(RHS);
685 /// Regards both *this and RHS as signed quantities and compares them for
686 /// the validity of the greater-than relationship.
687 /// @returns true if *this > RHS when both are considered signed.
688 /// @brief Signed greather than comparison
689 bool sgt(const APInt& RHS) const {
690 return !slt(RHS) && !eq(RHS);
693 /// Regards both *this and RHS as unsigned quantities and compares them for
694 /// validity of the greater-or-equal relationship.
695 /// @returns true if *this >= RHS when both are considered unsigned.
696 /// @brief Unsigned greater or equal comparison
697 bool uge(const APInt& RHS) const {
701 /// Regards both *this and RHS as signed quantities and compares them for
702 /// validity of the greater-or-equal relationship.
703 /// @returns true if *this >= RHS when both are considered signed.
704 /// @brief Signed greather or equal comparison
705 bool sge(const APInt& RHS) const {
710 /// @name Resizing Operators
712 /// Truncate the APInt to a specified width. It is an error to specify a width
713 /// that is greater than or equal to the current width.
714 /// @brief Truncate to new width.
715 APInt &trunc(uint32_t width);
717 /// This operation sign extends the APInt to a new width. If the high order
718 /// bit is set, the fill on the left will be done with 1 bits, otherwise zero.
719 /// It is an error to specify a width that is less than or equal to the
721 /// @brief Sign extend to a new width.
722 APInt &sext(uint32_t width);
724 /// This operation zero extends the APInt to a new width. The high order bits
725 /// are filled with 0 bits. It is an error to specify a width that is less
726 /// than or equal to the current width.
727 /// @brief Zero extend to a new width.
728 APInt &zext(uint32_t width);
730 /// Make this APInt have the bit width given by \p width. The value is sign
731 /// extended, truncated, or left alone to make it that width.
732 /// @brief Sign extend or truncate to width
733 APInt &sextOrTrunc(uint32_t width);
735 /// Make this APInt have the bit width given by \p width. The value is zero
736 /// extended, truncated, or left alone to make it that width.
737 /// @brief Zero extend or truncate to width
738 APInt &zextOrTrunc(uint32_t width);
741 /// @name Bit Manipulation Operators
743 /// @brief Set every bit to 1.
746 /// Set the given bit to 1 whose position is given as "bitPosition".
747 /// @brief Set a given bit to 1.
748 APInt& set(uint32_t bitPosition);
750 /// @brief Set every bit to 0.
753 /// Set the given bit to 0 whose position is given as "bitPosition".
754 /// @brief Set a given bit to 0.
755 APInt& clear(uint32_t bitPosition);
757 /// @brief Toggle every bit to its opposite value.
760 /// Toggle a given bit to its opposite value whose position is given
761 /// as "bitPosition".
762 /// @brief Toggles a given bit to its opposite value.
763 APInt& flip(uint32_t bitPosition);
766 /// @name Value Characterization Functions
769 /// @returns the total number of bits.
770 inline uint32_t getBitWidth() const {
774 /// Here one word's bitwidth equals to that of uint64_t.
775 /// @returns the number of words to hold the integer value of this APInt.
776 /// @brief Get the number of words.
777 inline uint32_t getNumWords() const {
778 return (BitWidth + APINT_BITS_PER_WORD - 1) / APINT_BITS_PER_WORD;
781 /// This function returns the number of active bits which is defined as the
782 /// bit width minus the number of leading zeros. This is used in several
783 /// computations to see how "wide" the value is.
784 /// @brief Compute the number of active bits in the value
785 inline uint32_t getActiveBits() const {
786 return BitWidth - countLeadingZeros();
789 /// This function returns the number of active words in the value of this
790 /// APInt. This is used in conjunction with getActiveData to extract the raw
791 /// value of the APInt.
792 inline uint32_t getActiveWords() const {
793 return whichWord(getActiveBits()-1) + 1;
796 /// Computes the minimum bit width for this APInt while considering it to be
797 /// a signed (and probably negative) value. If the value is not negative,
798 /// this function returns the same value as getActiveBits(). Otherwise, it
799 /// returns the smallest bit width that will retain the negative value. For
800 /// example, -1 can be written as 0b1 or 0xFFFFFFFFFF. 0b1 is shorter and so
801 /// for -1, this function will always return 1.
802 /// @brief Get the minimum bit size for this signed APInt
803 inline uint32_t getMinSignedBits() const {
805 return BitWidth - countLeadingOnes() + 1;
806 return getActiveBits();
809 /// This method attempts to return the value of this APInt as a zero extended
810 /// uint64_t. The bitwidth must be <= 64 or the value must fit within a
811 /// uint64_t. Otherwise an assertion will result.
812 /// @brief Get zero extended value
813 inline uint64_t getZExtValue() const {
816 assert(getActiveBits() <= 64 && "Too many bits for uint64_t");
820 /// This method attempts to return the value of this APInt as a sign extended
821 /// int64_t. The bit width must be <= 64 or the value must fit within an
822 /// int64_t. Otherwise an assertion will result.
823 /// @brief Get sign extended value
824 inline int64_t getSExtValue() const {
826 return int64_t(VAL << (APINT_BITS_PER_WORD - BitWidth)) >>
827 (APINT_BITS_PER_WORD - BitWidth);
828 assert(getActiveBits() <= 64 && "Too many bits for int64_t");
829 return int64_t(pVal[0]);
831 /// countLeadingZeros - This function is an APInt version of the
832 /// countLeadingZeros_{32,64} functions in MathExtras.h. It counts the number
833 /// of zeros from the most significant bit to the first one bit.
834 /// @returns getNumWords() * APINT_BITS_PER_WORD if the value is zero.
835 /// @returns the number of zeros from the most significant bit to the first
837 /// @brief Count the number of leading one bits.
838 uint32_t countLeadingZeros() const;
840 /// countLeadingOnes - This function counts the number of contiguous 1 bits
841 /// in the high order bits. The count stops when the first 0 bit is reached.
842 /// @returns 0 if the high order bit is not set
843 /// @returns the number of 1 bits from the most significant to the least
844 /// @brief Count the number of leading one bits.
845 uint32_t countLeadingOnes() const;
847 /// countTrailingZeros - This function is an APInt version of the
848 /// countTrailingZoers_{32,64} functions in MathExtras.h. It counts
849 /// the number of zeros from the least significant bit to the first one bit.
850 /// @returns getNumWords() * APINT_BITS_PER_WORD if the value is zero.
851 /// @returns the number of zeros from the least significant bit to the first
853 /// @brief Count the number of trailing zero bits.
854 uint32_t countTrailingZeros() const;
856 /// countPopulation - This function is an APInt version of the
857 /// countPopulation_{32,64} functions in MathExtras.h. It counts the number
858 /// of 1 bits in the APInt value.
859 /// @returns 0 if the value is zero.
860 /// @returns the number of set bits.
861 /// @brief Count the number of bits set.
862 uint32_t countPopulation() const;
865 /// @name Conversion Functions
868 /// This is used internally to convert an APInt to a string.
869 /// @brief Converts an APInt to a std::string
870 std::string toString(uint8_t radix, bool wantSigned) const;
872 /// Considers the APInt to be unsigned and converts it into a string in the
873 /// radix given. The radix can be 2, 8, 10 or 16.
874 /// @returns a character interpretation of the APInt
875 /// @brief Convert unsigned APInt to string representation.
876 inline std::string toString(uint8_t radix = 10) const {
877 return toString(radix, false);
880 /// Considers the APInt to be unsigned and converts it into a string in the
881 /// radix given. The radix can be 2, 8, 10 or 16.
882 /// @returns a character interpretation of the APInt
883 /// @brief Convert unsigned APInt to string representation.
884 inline std::string toStringSigned(uint8_t radix = 10) const {
885 return toString(radix, true);
888 /// @returns a byte-swapped representation of this APInt Value.
889 APInt byteSwap() const;
891 /// @brief Converts this APInt to a double value.
892 double roundToDouble(bool isSigned) const;
894 /// @brief Converts this unsigned APInt to a double value.
895 double roundToDouble() const {
896 return roundToDouble(false);
899 /// @brief Converts this signed APInt to a double value.
900 double signedRoundToDouble() const {
901 return roundToDouble(true);
904 /// The conversion does not do a translation from integer to double, it just
905 /// re-interprets the bits as a double. Note that it is valid to do this on
906 /// any bit width. Exactly 64 bits will be translated.
907 /// @brief Converts APInt bits to a double
908 double bitsToDouble() const {
913 T.I = (isSingleWord() ? VAL : pVal[0]);
917 /// The conversion does not do a translation from integer to float, it just
918 /// re-interprets the bits as a float. Note that it is valid to do this on
919 /// any bit width. Exactly 32 bits will be translated.
920 /// @brief Converts APInt bits to a double
921 float bitsToFloat() const {
926 T.I = uint32_t((isSingleWord() ? VAL : pVal[0]));
930 /// The conversion does not do a translation from double to integer, it just
931 /// re-interprets the bits of the double. Note that it is valid to do this on
932 /// any bit width but bits from V may get truncated.
933 /// @brief Converts a double to APInt bits.
934 APInt& doubleToBits(double V) {
944 return clearUnusedBits();
947 /// The conversion does not do a translation from float to integer, it just
948 /// re-interprets the bits of the float. Note that it is valid to do this on
949 /// any bit width but bits from V may get truncated.
950 /// @brief Converts a float to APInt bits.
951 APInt& floatToBits(float V) {
961 return clearUnusedBits();
965 /// @name Mathematics Operations
968 /// @returns the floor log base 2 of this APInt.
969 inline uint32_t logBase2() const {
970 return BitWidth - 1 - countLeadingZeros();
973 /// @brief Compute the square root
976 /// If *this is < 0 then return -(*this), otherwise *this;
977 /// @brief Get the absolute value;
986 inline bool operator==(uint64_t V1, const APInt& V2) {
990 inline bool operator!=(uint64_t V1, const APInt& V2) {
996 /// @brief Determine the smaller of two APInts considered to be signed.
997 inline APInt smin(const APInt &A, const APInt &B) {
998 return A.slt(B) ? A : B;
1001 /// @brief Determine the larger of two APInts considered to be signed.
1002 inline APInt smax(const APInt &A, const APInt &B) {
1003 return A.sgt(B) ? A : B;
1006 /// @brief Determine the smaller of two APInts considered to be signed.
1007 inline APInt umin(const APInt &A, const APInt &B) {
1008 return A.ult(B) ? A : B;
1011 /// @brief Determine the larger of two APInts considered to be unsigned.
1012 inline APInt umax(const APInt &A, const APInt &B) {
1013 return A.ugt(B) ? A : B;
1016 /// @brief Check if the specified APInt has a N-bits integer value.
1017 inline bool isIntN(uint32_t N, const APInt& APIVal) {
1018 return APIVal.isIntN(N);
1021 /// @returns true if the argument APInt value is a sequence of ones
1022 /// starting at the least significant bit with the remainder zero.
1023 inline const bool isMask(uint32_t numBits, const APInt& APIVal) {
1024 return APIVal.getBoolValue() && ((APIVal + APInt(numBits,1)) & APIVal) == 0;
1027 /// @returns true if the argument APInt value contains a sequence of ones
1028 /// with the remainder zero.
1029 inline const bool isShiftedMask(uint32_t numBits, const APInt& APIVal) {
1030 return isMask(numBits, (APIVal - APInt(numBits,1)) | APIVal);
1033 /// @returns a byte-swapped representation of the specified APInt Value.
1034 inline APInt byteSwap(const APInt& APIVal) {
1035 return APIVal.byteSwap();
1038 /// @returns the floor log base 2 of the specified APInt value.
1039 inline uint32_t logBase2(const APInt& APIVal) {
1040 return APIVal.logBase2();
1043 /// GreatestCommonDivisor - This function returns the greatest common
1044 /// divisor of the two APInt values using Enclid's algorithm.
1045 /// @returns the greatest common divisor of Val1 and Val2
1046 /// @brief Compute GCD of two APInt values.
1047 APInt GreatestCommonDivisor(const APInt& Val1, const APInt& Val2);
1049 /// Treats the APInt as an unsigned value for conversion purposes.
1050 /// @brief Converts the given APInt to a double value.
1051 inline double RoundAPIntToDouble(const APInt& APIVal) {
1052 return APIVal.roundToDouble();
1055 /// Treats the APInt as a signed value for conversion purposes.
1056 /// @brief Converts the given APInt to a double value.
1057 inline double RoundSignedAPIntToDouble(const APInt& APIVal) {
1058 return APIVal.signedRoundToDouble();
1061 /// @brief Converts the given APInt to a float vlalue.
1062 inline float RoundAPIntToFloat(const APInt& APIVal) {
1063 return float(RoundAPIntToDouble(APIVal));
1066 /// Treast the APInt as a signed value for conversion purposes.
1067 /// @brief Converts the given APInt to a float value.
1068 inline float RoundSignedAPIntToFloat(const APInt& APIVal) {
1069 return float(APIVal.signedRoundToDouble());
1072 /// RoundDoubleToAPInt - This function convert a double value to an APInt value.
1073 /// @brief Converts the given double value into a APInt.
1074 APInt RoundDoubleToAPInt(double Double, uint32_t width);
1076 /// RoundFloatToAPInt - Converts a float value into an APInt value.
1077 /// @brief Converts a float value into a APInt.
1078 inline APInt RoundFloatToAPInt(float Float, uint32_t width) {
1079 return RoundDoubleToAPInt(double(Float), width);
1082 /// Arithmetic right-shift the APInt by shiftAmt.
1083 /// @brief Arithmetic right-shift function.
1084 inline APInt ashr(const APInt& LHS, uint32_t shiftAmt) {
1085 return LHS.ashr(shiftAmt);
1088 /// Logical right-shift the APInt by shiftAmt.
1089 /// @brief Logical right-shift function.
1090 inline APInt lshr(const APInt& LHS, uint32_t shiftAmt) {
1091 return LHS.lshr(shiftAmt);
1094 /// Left-shift the APInt by shiftAmt.
1095 /// @brief Left-shift function.
1096 inline APInt shl(const APInt& LHS, uint32_t shiftAmt) {
1097 return LHS.shl(shiftAmt);
1100 /// Signed divide APInt LHS by APInt RHS.
1101 /// @brief Signed division function for APInt.
1102 inline APInt sdiv(const APInt& LHS, const APInt& RHS) {
1103 return LHS.sdiv(RHS);
1106 /// Unsigned divide APInt LHS by APInt RHS.
1107 /// @brief Unsigned division function for APInt.
1108 inline APInt udiv(const APInt& LHS, const APInt& RHS) {
1109 return LHS.udiv(RHS);
1112 /// Signed remainder operation on APInt.
1113 /// @brief Function for signed remainder operation.
1114 inline APInt srem(const APInt& LHS, const APInt& RHS) {
1115 return LHS.srem(RHS);
1118 /// Unsigned remainder operation on APInt.
1119 /// @brief Function for unsigned remainder operation.
1120 inline APInt urem(const APInt& LHS, const APInt& RHS) {
1121 return LHS.urem(RHS);
1124 /// Performs multiplication on APInt values.
1125 /// @brief Function for multiplication operation.
1126 inline APInt mul(const APInt& LHS, const APInt& RHS) {
1130 /// Performs addition on APInt values.
1131 /// @brief Function for addition operation.
1132 inline APInt add(const APInt& LHS, const APInt& RHS) {
1136 /// Performs subtraction on APInt values.
1137 /// @brief Function for subtraction operation.
1138 inline APInt sub(const APInt& LHS, const APInt& RHS) {
1142 /// Performs bitwise AND operation on APInt LHS and
1144 /// @brief Bitwise AND function for APInt.
1145 inline APInt And(const APInt& LHS, const APInt& RHS) {
1149 /// Performs bitwise OR operation on APInt LHS and APInt RHS.
1150 /// @brief Bitwise OR function for APInt.
1151 inline APInt Or(const APInt& LHS, const APInt& RHS) {
1155 /// Performs bitwise XOR operation on APInt.
1156 /// @brief Bitwise XOR function for APInt.
1157 inline APInt Xor(const APInt& LHS, const APInt& RHS) {
1161 /// Performs a bitwise complement operation on APInt.
1162 /// @brief Bitwise complement function.
1163 inline APInt Not(const APInt& APIVal) {
1167 } // End of APIntOps namespace
1169 } // End of llvm namespace