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 /// This converts the APInt to a boolean valy as a test against zero.
276 /// @brief Boolean conversion function.
277 inline bool getBoolValue() const {
278 return countLeadingZeros() != BitWidth;
282 /// @name Value Generators
284 /// @brief Gets maximum unsigned value of APInt for specific bit width.
285 static APInt getMaxValue(uint32_t numBits) {
286 return APInt(numBits, 0).set();
289 /// @brief Gets maximum signed value of APInt for a specific bit width.
290 static APInt getSignedMaxValue(uint32_t numBits) {
291 return APInt(numBits, 0).set().clear(numBits - 1);
294 /// @brief Gets minimum unsigned value of APInt for a specific bit width.
295 static APInt getMinValue(uint32_t numBits) {
296 return APInt(numBits, 0);
299 /// @brief Gets minimum signed value of APInt for a specific bit width.
300 static APInt getSignedMinValue(uint32_t numBits) {
301 return APInt(numBits, 0).set(numBits - 1);
304 /// getSignBit - This is just a wrapper function of getSignedMinValue(), and
305 /// it helps code readability when we want to get a SignBit.
306 /// @brief Get the SignBit for a specific bit width.
307 inline static APInt getSignBit(uint32_t BitWidth) {
308 return getSignedMinValue(BitWidth);
311 /// @returns the all-ones value for an APInt of the specified bit-width.
312 /// @brief Get the all-ones value.
313 static APInt getAllOnesValue(uint32_t numBits) {
314 return APInt(numBits, 0).set();
317 /// @returns the '0' value for an APInt of the specified bit-width.
318 /// @brief Get the '0' value.
319 static APInt getNullValue(uint32_t numBits) {
320 return APInt(numBits, 0);
323 /// Get an APInt with the same BitWidth as this APInt, just zero mask
324 /// the low bits and right shift to the least significant bit.
325 /// @returns the high "numBits" bits of this APInt.
326 APInt getHiBits(uint32_t numBits) const;
328 /// Get an APInt with the same BitWidth as this APInt, just zero mask
330 /// @returns the low "numBits" bits of this APInt.
331 APInt getLoBits(uint32_t numBits) const;
333 /// Constructs an APInt value that has a contiguous range of bits set. The
334 /// bits from loBit to hiBit will be set. All other bits will be zero. For
335 /// example, with parameters(32, 15, 0) you would get 0x0000FFFF. If hiBit is
336 /// less than loBit then the set bits "wrap". For example, with
337 /// parameters (32, 3, 28), you would get 0xF000000F.
338 /// @param numBits the intended bit width of the result
339 /// @param loBit the index of the lowest bit set.
340 /// @param hiBit the index of the highest bit set.
341 /// @returns An APInt value with the requested bits set.
342 /// @brief Get a value with a block of bits set.
343 static APInt getBitsSet(uint32_t numBits, uint32_t loBit, uint32_t hiBit) {
344 assert(hiBit < numBits && "hiBit out of range");
345 assert(loBit < numBits && "loBit out of range");
347 return getLowBitsSet(numBits, hiBit+1) |
348 getHighBitsSet(numBits, numBits-loBit+1);
349 return getLowBitsSet(numBits, hiBit-loBit+1).shl(loBit);
352 /// Constructs an APInt value that has the top hiBitsSet bits set.
353 /// @param numBits the bitwidth of the result
354 /// @param hiBitsSet the number of high-order bits set in the result.
355 /// @brief Get a value with high bits set
356 static APInt getHighBitsSet(uint32_t numBits, uint32_t hiBitsSet) {
357 assert(hiBitsSet <= numBits && "Too many bits to set!");
358 // Handle a degenerate case, to avoid shifting by word size
360 return APInt(numBits, 0);
361 uint32_t shiftAmt = numBits - hiBitsSet;
362 // For small values, return quickly
363 if (numBits <= APINT_BITS_PER_WORD)
364 return APInt(numBits, ~0ULL << shiftAmt);
365 return (~APInt(numBits, 0)).shl(shiftAmt);
368 /// Constructs an APInt value that has the bottom loBitsSet bits set.
369 /// @param numBits the bitwidth of the result
370 /// @param loBitsSet the number of low-order bits set in the result.
371 /// @brief Get a value with low bits set
372 static APInt getLowBitsSet(uint32_t numBits, uint32_t loBitsSet) {
373 assert(loBitsSet <= numBits && "Too many bits to set!");
374 // Handle a degenerate case, to avoid shifting by word size
376 return APInt(numBits, 0);
377 uint32_t shiftAmt = numBits - loBitsSet;
378 // For small values, return quickly
379 if (numBits <= APINT_BITS_PER_WORD)
380 return APInt(numBits, ~0ULL >> shiftAmt);
381 return (~APInt(numBits, 0)).lshr(shiftAmt);
384 /// The hash value is computed as the sum of the words and the bit width.
385 /// @returns A hash value computed from the sum of the APInt words.
386 /// @brief Get a hash value based on this APInt
387 uint64_t getHashValue() const;
389 /// This function returns a pointer to the internal storage of the APInt.
390 /// This is useful for writing out the APInt in binary form without any
392 inline const uint64_t* getRawData() const {
398 /// @brief Set a sepcific word in the value to a new value.
399 inline void setWordToValue(uint32_t idx, uint64_t Val) {
400 assert(idx < getNumWords() && "Invalid word array index");
408 /// @name Unary Operators
410 /// @returns a new APInt value representing *this incremented by one
411 /// @brief Postfix increment operator.
412 inline const APInt operator++(int) {
418 /// @returns *this incremented by one
419 /// @brief Prefix increment operator.
422 /// @returns a new APInt representing *this decremented by one.
423 /// @brief Postfix decrement operator.
424 inline const APInt operator--(int) {
430 /// @returns *this decremented by one.
431 /// @brief Prefix decrement operator.
434 /// Performs a bitwise complement operation on this APInt.
435 /// @returns an APInt that is the bitwise complement of *this
436 /// @brief Unary bitwise complement operator.
437 APInt operator~() const;
439 /// Negates *this using two's complement logic.
440 /// @returns An APInt value representing the negation of *this.
441 /// @brief Unary negation operator
442 inline APInt operator-() const {
443 return APInt(BitWidth, 0) - (*this);
446 /// Performs logical negation operation on this APInt.
447 /// @returns true if *this is zero, false otherwise.
448 /// @brief Logical negation operator.
449 bool operator !() const;
452 /// @name Assignment Operators
454 /// @returns *this after assignment of RHS.
455 /// @brief Copy assignment operator.
456 APInt& operator=(const APInt& RHS);
458 /// The RHS value is assigned to *this. If the significant bits in RHS exceed
459 /// the bit width, the excess bits are truncated. If the bit width is larger
460 /// than 64, the value is zero filled in the unspecified high order bits.
461 /// @returns *this after assignment of RHS value.
462 /// @brief Assignment operator.
463 APInt& operator=(uint64_t RHS);
465 /// Performs a bitwise AND operation on this APInt and RHS. The result is
466 /// assigned to *this.
467 /// @returns *this after ANDing with RHS.
468 /// @brief Bitwise AND assignment operator.
469 APInt& operator&=(const APInt& RHS);
471 /// Performs a bitwise OR operation on this APInt and RHS. The result is
473 /// @returns *this after ORing with RHS.
474 /// @brief Bitwise OR assignment operator.
475 APInt& operator|=(const APInt& RHS);
477 /// Performs a bitwise XOR operation on this APInt and RHS. The result is
478 /// assigned to *this.
479 /// @returns *this after XORing with RHS.
480 /// @brief Bitwise XOR assignment operator.
481 APInt& operator^=(const APInt& RHS);
483 /// Multiplies this APInt by RHS and assigns the result to *this.
485 /// @brief Multiplication assignment operator.
486 APInt& operator*=(const APInt& RHS);
488 /// Adds RHS to *this and assigns the result to *this.
490 /// @brief Addition assignment operator.
491 APInt& operator+=(const APInt& RHS);
493 /// Subtracts RHS from *this and assigns the result to *this.
495 /// @brief Subtraction assignment operator.
496 APInt& operator-=(const APInt& RHS);
498 /// Shifts *this left by shiftAmt and assigns the result to *this.
499 /// @returns *this after shifting left by shiftAmt
500 /// @brief Left-shift assignment function.
501 inline APInt& operator<<=(uint32_t shiftAmt) {
502 *this = shl(shiftAmt);
507 /// @name Binary Operators
509 /// Performs a bitwise AND operation on *this and RHS.
510 /// @returns An APInt value representing the bitwise AND of *this and RHS.
511 /// @brief Bitwise AND operator.
512 APInt operator&(const APInt& RHS) const;
513 APInt And(const APInt& RHS) const {
514 return this->operator&(RHS);
517 /// Performs a bitwise OR operation on *this and RHS.
518 /// @returns An APInt value representing the bitwise OR of *this and RHS.
519 /// @brief Bitwise OR operator.
520 APInt operator|(const APInt& RHS) const;
521 APInt Or(const APInt& RHS) const {
522 return this->operator|(RHS);
525 /// Performs a bitwise XOR operation on *this and RHS.
526 /// @returns An APInt value representing the bitwise XOR of *this and RHS.
527 /// @brief Bitwise XOR operator.
528 APInt operator^(const APInt& RHS) const;
529 APInt Xor(const APInt& RHS) const {
530 return this->operator^(RHS);
533 /// Multiplies this APInt by RHS and returns the result.
534 /// @brief Multiplication operator.
535 APInt operator*(const APInt& RHS) const;
537 /// Adds RHS to this APInt and returns the result.
538 /// @brief Addition operator.
539 APInt operator+(const APInt& RHS) const;
540 APInt operator+(uint64_t RHS) const {
541 return (*this) + APInt(BitWidth, RHS);
544 /// Subtracts RHS from this APInt and returns the result.
545 /// @brief Subtraction operator.
546 APInt operator-(const APInt& RHS) const;
547 APInt operator-(uint64_t RHS) const {
548 return (*this) - APInt(BitWidth, RHS);
551 /// Arithmetic right-shift this APInt by shiftAmt.
552 /// @brief Arithmetic right-shift function.
553 APInt ashr(uint32_t shiftAmt) const;
555 /// Logical right-shift this APInt by shiftAmt.
556 /// @brief Logical right-shift function.
557 APInt lshr(uint32_t shiftAmt) const;
559 /// Left-shift this APInt by shiftAmt.
560 /// @brief Left-shift function.
561 APInt shl(uint32_t shiftAmt) const;
563 /// Perform an unsigned divide operation on this APInt by RHS. Both this and
564 /// RHS are treated as unsigned quantities for purposes of this division.
565 /// @returns a new APInt value containing the division result
566 /// @brief Unsigned division operation.
567 APInt udiv(const APInt& RHS) const;
569 /// Signed divide this APInt by APInt RHS.
570 /// @brief Signed division function for APInt.
571 inline APInt sdiv(const APInt& RHS) const {
573 if (RHS.isNegative())
574 return (-(*this)).udiv(-RHS);
576 return -((-(*this)).udiv(RHS));
577 else if (RHS.isNegative())
578 return -(this->udiv(-RHS));
579 return this->udiv(RHS);
582 /// Perform an unsigned remainder operation on this APInt with RHS being the
583 /// divisor. Both this and RHS are treated as unsigned quantities for purposes
584 /// of this operation. Note that this is a true remainder operation and not
585 /// a modulo operation because the sign follows the sign of the dividend
587 /// @returns a new APInt value containing the remainder result
588 /// @brief Unsigned remainder operation.
589 APInt urem(const APInt& RHS) const;
591 /// Signed remainder operation on APInt.
592 /// @brief Function for signed remainder operation.
593 inline APInt srem(const APInt& RHS) const {
595 if (RHS.isNegative())
596 return -((-(*this)).urem(-RHS));
598 return -((-(*this)).urem(RHS));
599 else if (RHS.isNegative())
600 return this->urem(-RHS);
601 return this->urem(RHS);
604 /// @returns the bit value at bitPosition
605 /// @brief Array-indexing support.
606 bool operator[](uint32_t bitPosition) const;
609 /// @name Comparison Operators
611 /// Compares this APInt with RHS for the validity of the equality
613 /// @brief Equality operator.
614 bool operator==(const APInt& RHS) const;
616 /// Compares this APInt with a uint64_t for the validity of the equality
618 /// @returns true if *this == Val
619 /// @brief Equality operator.
620 bool operator==(uint64_t Val) const;
622 /// Compares this APInt with RHS for the validity of the equality
624 /// @returns true if *this == Val
625 /// @brief Equality comparison.
626 bool eq(const APInt &RHS) const {
627 return (*this) == RHS;
630 /// Compares this APInt with RHS for the validity of the inequality
632 /// @returns true if *this != Val
633 /// @brief Inequality operator.
634 inline bool operator!=(const APInt& RHS) const {
635 return !((*this) == RHS);
638 /// Compares this APInt with a uint64_t for the validity of the inequality
640 /// @returns true if *this != Val
641 /// @brief Inequality operator.
642 inline bool operator!=(uint64_t Val) const {
643 return !((*this) == Val);
646 /// Compares this APInt with RHS for the validity of the inequality
648 /// @returns true if *this != Val
649 /// @brief Inequality comparison
650 bool ne(const APInt &RHS) const {
651 return !((*this) == RHS);
654 /// Regards both *this and RHS as unsigned quantities and compares them for
655 /// the validity of the less-than relationship.
656 /// @returns true if *this < RHS when both are considered unsigned.
657 /// @brief Unsigned less than comparison
658 bool ult(const APInt& RHS) const;
660 /// Regards both *this and RHS as signed quantities and compares them for
661 /// validity of the less-than relationship.
662 /// @returns true if *this < RHS when both are considered signed.
663 /// @brief Signed less than comparison
664 bool slt(const APInt& RHS) const;
666 /// Regards both *this and RHS as unsigned quantities and compares them for
667 /// validity of the less-or-equal relationship.
668 /// @returns true if *this <= RHS when both are considered unsigned.
669 /// @brief Unsigned less or equal comparison
670 bool ule(const APInt& RHS) const {
671 return ult(RHS) || eq(RHS);
674 /// Regards both *this and RHS as signed quantities and compares them for
675 /// validity of the less-or-equal relationship.
676 /// @returns true if *this <= RHS when both are considered signed.
677 /// @brief Signed less or equal comparison
678 bool sle(const APInt& RHS) const {
679 return slt(RHS) || eq(RHS);
682 /// Regards both *this and RHS as unsigned quantities and compares them for
683 /// the validity of the greater-than relationship.
684 /// @returns true if *this > RHS when both are considered unsigned.
685 /// @brief Unsigned greather than comparison
686 bool ugt(const APInt& RHS) const {
687 return !ult(RHS) && !eq(RHS);
690 /// Regards both *this and RHS as signed quantities and compares them for
691 /// the validity of the greater-than relationship.
692 /// @returns true if *this > RHS when both are considered signed.
693 /// @brief Signed greather than comparison
694 bool sgt(const APInt& RHS) const {
695 return !slt(RHS) && !eq(RHS);
698 /// Regards both *this and RHS as unsigned quantities and compares them for
699 /// validity of the greater-or-equal relationship.
700 /// @returns true if *this >= RHS when both are considered unsigned.
701 /// @brief Unsigned greater or equal comparison
702 bool uge(const APInt& RHS) const {
706 /// Regards both *this and RHS as signed quantities and compares them for
707 /// validity of the greater-or-equal relationship.
708 /// @returns true if *this >= RHS when both are considered signed.
709 /// @brief Signed greather or equal comparison
710 bool sge(const APInt& RHS) const {
715 /// @name Resizing Operators
717 /// Truncate the APInt to a specified width. It is an error to specify a width
718 /// that is greater than or equal to the current width.
719 /// @brief Truncate to new width.
720 APInt &trunc(uint32_t width);
722 /// This operation sign extends the APInt to a new width. If the high order
723 /// bit is set, the fill on the left will be done with 1 bits, otherwise zero.
724 /// It is an error to specify a width that is less than or equal to the
726 /// @brief Sign extend to a new width.
727 APInt &sext(uint32_t width);
729 /// This operation zero extends the APInt to a new width. The high order bits
730 /// are filled with 0 bits. It is an error to specify a width that is less
731 /// than or equal to the current width.
732 /// @brief Zero extend to a new width.
733 APInt &zext(uint32_t width);
735 /// Make this APInt have the bit width given by \p width. The value is sign
736 /// extended, truncated, or left alone to make it that width.
737 /// @brief Sign extend or truncate to width
738 APInt &sextOrTrunc(uint32_t width);
740 /// Make this APInt have the bit width given by \p width. The value is zero
741 /// extended, truncated, or left alone to make it that width.
742 /// @brief Zero extend or truncate to width
743 APInt &zextOrTrunc(uint32_t width);
745 /// This is a help function for convenience. If the given \p width equals to
746 /// this APInt's BitWidth, just return this APInt, otherwise, just zero
748 inline APInt &zextOrCopy(uint32_t width) {
749 if (width == BitWidth)
755 /// @name Bit Manipulation Operators
757 /// @brief Set every bit to 1.
760 /// Set the given bit to 1 whose position is given as "bitPosition".
761 /// @brief Set a given bit to 1.
762 APInt& set(uint32_t bitPosition);
764 /// @brief Set every bit to 0.
767 /// Set the given bit to 0 whose position is given as "bitPosition".
768 /// @brief Set a given bit to 0.
769 APInt& clear(uint32_t bitPosition);
771 /// @brief Toggle every bit to its opposite value.
774 /// Toggle a given bit to its opposite value whose position is given
775 /// as "bitPosition".
776 /// @brief Toggles a given bit to its opposite value.
777 APInt& flip(uint32_t bitPosition);
780 /// @name Value Characterization Functions
783 /// @returns the total number of bits.
784 inline uint32_t getBitWidth() const {
788 /// Here one word's bitwidth equals to that of uint64_t.
789 /// @returns the number of words to hold the integer value of this APInt.
790 /// @brief Get the number of words.
791 inline uint32_t getNumWords() const {
792 return (BitWidth + APINT_BITS_PER_WORD - 1) / APINT_BITS_PER_WORD;
795 /// This function returns the number of active bits which is defined as the
796 /// bit width minus the number of leading zeros. This is used in several
797 /// computations to see how "wide" the value is.
798 /// @brief Compute the number of active bits in the value
799 inline uint32_t getActiveBits() const {
800 return BitWidth - countLeadingZeros();
803 /// This function returns the number of active words in the value of this
804 /// APInt. This is used in conjunction with getActiveData to extract the raw
805 /// value of the APInt.
806 inline uint32_t getActiveWords() const {
807 return whichWord(getActiveBits()-1) + 1;
810 /// Computes the minimum bit width for this APInt while considering it to be
811 /// a signed (and probably negative) value. If the value is not negative,
812 /// this function returns the same value as getActiveBits(). Otherwise, it
813 /// returns the smallest bit width that will retain the negative value. For
814 /// example, -1 can be written as 0b1 or 0xFFFFFFFFFF. 0b1 is shorter and so
815 /// for -1, this function will always return 1.
816 /// @brief Get the minimum bit size for this signed APInt
817 inline uint32_t getMinSignedBits() const {
819 return BitWidth - countLeadingOnes() + 1;
820 return getActiveBits();
823 /// This method attempts to return the value of this APInt as a zero extended
824 /// uint64_t. The bitwidth must be <= 64 or the value must fit within a
825 /// uint64_t. Otherwise an assertion will result.
826 /// @brief Get zero extended value
827 inline uint64_t getZExtValue() const {
830 assert(getActiveBits() <= 64 && "Too many bits for uint64_t");
834 /// This method attempts to return the value of this APInt as a sign extended
835 /// int64_t. The bit width must be <= 64 or the value must fit within an
836 /// int64_t. Otherwise an assertion will result.
837 /// @brief Get sign extended value
838 inline int64_t getSExtValue() const {
840 return int64_t(VAL << (APINT_BITS_PER_WORD - BitWidth)) >>
841 (APINT_BITS_PER_WORD - BitWidth);
842 assert(getActiveBits() <= 64 && "Too many bits for int64_t");
843 return int64_t(pVal[0]);
845 /// countLeadingZeros - This function is an APInt version of the
846 /// countLeadingZeros_{32,64} functions in MathExtras.h. It counts the number
847 /// of zeros from the most significant bit to the first one bit.
848 /// @returns getNumWords() * APINT_BITS_PER_WORD if the value is zero.
849 /// @returns the number of zeros from the most significant bit to the first
851 /// @brief Count the number of leading one bits.
852 uint32_t countLeadingZeros() const;
854 /// countLeadingOnes - This function counts the number of contiguous 1 bits
855 /// in the high order bits. The count stops when the first 0 bit is reached.
856 /// @returns 0 if the high order bit is not set
857 /// @returns the number of 1 bits from the most significant to the least
858 /// @brief Count the number of leading one bits.
859 uint32_t countLeadingOnes() const;
861 /// countTrailingZeros - This function is an APInt version of the
862 /// countTrailingZoers_{32,64} functions in MathExtras.h. It counts
863 /// the number of zeros from the least significant bit to the first one bit.
864 /// @returns getNumWords() * APINT_BITS_PER_WORD if the value is zero.
865 /// @returns the number of zeros from the least significant bit to the first
867 /// @brief Count the number of trailing zero bits.
868 uint32_t countTrailingZeros() const;
870 /// countPopulation - This function is an APInt version of the
871 /// countPopulation_{32,64} functions in MathExtras.h. It counts the number
872 /// of 1 bits in the APInt value.
873 /// @returns 0 if the value is zero.
874 /// @returns the number of set bits.
875 /// @brief Count the number of bits set.
876 uint32_t countPopulation() const;
879 /// @name Conversion Functions
882 /// This is used internally to convert an APInt to a string.
883 /// @brief Converts an APInt to a std::string
884 std::string toString(uint8_t radix, bool wantSigned) const;
886 /// Considers the APInt to be unsigned and converts it into a string in the
887 /// radix given. The radix can be 2, 8, 10 or 16.
888 /// @returns a character interpretation of the APInt
889 /// @brief Convert unsigned APInt to string representation.
890 inline std::string toString(uint8_t radix = 10) const {
891 return toString(radix, false);
894 /// Considers the APInt to be unsigned and converts it into a string in the
895 /// radix given. The radix can be 2, 8, 10 or 16.
896 /// @returns a character interpretation of the APInt
897 /// @brief Convert unsigned APInt to string representation.
898 inline std::string toStringSigned(uint8_t radix = 10) const {
899 return toString(radix, true);
902 /// @returns a byte-swapped representation of this APInt Value.
903 APInt byteSwap() const;
905 /// @brief Converts this APInt to a double value.
906 double roundToDouble(bool isSigned) const;
908 /// @brief Converts this unsigned APInt to a double value.
909 double roundToDouble() const {
910 return roundToDouble(false);
913 /// @brief Converts this signed APInt to a double value.
914 double signedRoundToDouble() const {
915 return roundToDouble(true);
918 /// The conversion does not do a translation from integer to double, it just
919 /// re-interprets the bits as a double. Note that it is valid to do this on
920 /// any bit width. Exactly 64 bits will be translated.
921 /// @brief Converts APInt bits to a double
922 double bitsToDouble() const {
927 T.I = (isSingleWord() ? VAL : pVal[0]);
931 /// The conversion does not do a translation from integer to float, it just
932 /// re-interprets the bits as a float. Note that it is valid to do this on
933 /// any bit width. Exactly 32 bits will be translated.
934 /// @brief Converts APInt bits to a double
935 float bitsToFloat() const {
940 T.I = uint32_t((isSingleWord() ? VAL : pVal[0]));
944 /// The conversion does not do a translation from double to integer, it just
945 /// re-interprets the bits of the double. Note that it is valid to do this on
946 /// any bit width but bits from V may get truncated.
947 /// @brief Converts a double to APInt bits.
948 APInt& doubleToBits(double V) {
958 return clearUnusedBits();
961 /// The conversion does not do a translation from float to integer, it just
962 /// re-interprets the bits of the float. Note that it is valid to do this on
963 /// any bit width but bits from V may get truncated.
964 /// @brief Converts a float to APInt bits.
965 APInt& floatToBits(float V) {
975 return clearUnusedBits();
979 /// @name Mathematics Operations
982 /// @returns the floor log base 2 of this APInt.
983 inline uint32_t logBase2() const {
984 return BitWidth - 1 - countLeadingZeros();
987 /// @brief Compute the square root
990 /// If *this is < 0 then return -(*this), otherwise *this;
991 /// @brief Get the absolute value;
1000 inline bool operator==(uint64_t V1, const APInt& V2) {
1004 inline bool operator!=(uint64_t V1, const APInt& V2) {
1008 namespace APIntOps {
1010 /// @brief Determine the smaller of two APInts considered to be signed.
1011 inline APInt smin(const APInt &A, const APInt &B) {
1012 return A.slt(B) ? A : B;
1015 /// @brief Determine the larger of two APInts considered to be signed.
1016 inline APInt smax(const APInt &A, const APInt &B) {
1017 return A.sgt(B) ? A : B;
1020 /// @brief Determine the smaller of two APInts considered to be signed.
1021 inline APInt umin(const APInt &A, const APInt &B) {
1022 return A.ult(B) ? A : B;
1025 /// @brief Determine the larger of two APInts considered to be unsigned.
1026 inline APInt umax(const APInt &A, const APInt &B) {
1027 return A.ugt(B) ? A : B;
1030 /// @brief Check if the specified APInt has a N-bits integer value.
1031 inline bool isIntN(uint32_t N, const APInt& APIVal) {
1032 return APIVal.isIntN(N);
1035 /// @returns true if the argument APInt value is a sequence of ones
1036 /// starting at the least significant bit with the remainder zero.
1037 inline const bool isMask(uint32_t numBits, const APInt& APIVal) {
1038 return APIVal.getBoolValue() && ((APIVal + APInt(numBits,1)) & APIVal) == 0;
1041 /// @returns true if the argument APInt value contains a sequence of ones
1042 /// with the remainder zero.
1043 inline const bool isShiftedMask(uint32_t numBits, const APInt& APIVal) {
1044 return isMask(numBits, (APIVal - APInt(numBits,1)) | APIVal);
1047 /// @returns a byte-swapped representation of the specified APInt Value.
1048 inline APInt byteSwap(const APInt& APIVal) {
1049 return APIVal.byteSwap();
1052 /// @returns the floor log base 2 of the specified APInt value.
1053 inline uint32_t logBase2(const APInt& APIVal) {
1054 return APIVal.logBase2();
1057 /// GreatestCommonDivisor - This function returns the greatest common
1058 /// divisor of the two APInt values using Enclid's algorithm.
1059 /// @returns the greatest common divisor of Val1 and Val2
1060 /// @brief Compute GCD of two APInt values.
1061 APInt GreatestCommonDivisor(const APInt& Val1, const APInt& Val2);
1063 /// Treats the APInt as an unsigned value for conversion purposes.
1064 /// @brief Converts the given APInt to a double value.
1065 inline double RoundAPIntToDouble(const APInt& APIVal) {
1066 return APIVal.roundToDouble();
1069 /// Treats the APInt as a signed value for conversion purposes.
1070 /// @brief Converts the given APInt to a double value.
1071 inline double RoundSignedAPIntToDouble(const APInt& APIVal) {
1072 return APIVal.signedRoundToDouble();
1075 /// @brief Converts the given APInt to a float vlalue.
1076 inline float RoundAPIntToFloat(const APInt& APIVal) {
1077 return float(RoundAPIntToDouble(APIVal));
1080 /// Treast the APInt as a signed value for conversion purposes.
1081 /// @brief Converts the given APInt to a float value.
1082 inline float RoundSignedAPIntToFloat(const APInt& APIVal) {
1083 return float(APIVal.signedRoundToDouble());
1086 /// RoundDoubleToAPInt - This function convert a double value to an APInt value.
1087 /// @brief Converts the given double value into a APInt.
1088 APInt RoundDoubleToAPInt(double Double, uint32_t width);
1090 /// RoundFloatToAPInt - Converts a float value into an APInt value.
1091 /// @brief Converts a float value into a APInt.
1092 inline APInt RoundFloatToAPInt(float Float, uint32_t width) {
1093 return RoundDoubleToAPInt(double(Float), width);
1096 /// Arithmetic right-shift the APInt by shiftAmt.
1097 /// @brief Arithmetic right-shift function.
1098 inline APInt ashr(const APInt& LHS, uint32_t shiftAmt) {
1099 return LHS.ashr(shiftAmt);
1102 /// Logical right-shift the APInt by shiftAmt.
1103 /// @brief Logical right-shift function.
1104 inline APInt lshr(const APInt& LHS, uint32_t shiftAmt) {
1105 return LHS.lshr(shiftAmt);
1108 /// Left-shift the APInt by shiftAmt.
1109 /// @brief Left-shift function.
1110 inline APInt shl(const APInt& LHS, uint32_t shiftAmt) {
1111 return LHS.shl(shiftAmt);
1114 /// Signed divide APInt LHS by APInt RHS.
1115 /// @brief Signed division function for APInt.
1116 inline APInt sdiv(const APInt& LHS, const APInt& RHS) {
1117 return LHS.sdiv(RHS);
1120 /// Unsigned divide APInt LHS by APInt RHS.
1121 /// @brief Unsigned division function for APInt.
1122 inline APInt udiv(const APInt& LHS, const APInt& RHS) {
1123 return LHS.udiv(RHS);
1126 /// Signed remainder operation on APInt.
1127 /// @brief Function for signed remainder operation.
1128 inline APInt srem(const APInt& LHS, const APInt& RHS) {
1129 return LHS.srem(RHS);
1132 /// Unsigned remainder operation on APInt.
1133 /// @brief Function for unsigned remainder operation.
1134 inline APInt urem(const APInt& LHS, const APInt& RHS) {
1135 return LHS.urem(RHS);
1138 /// Performs multiplication on APInt values.
1139 /// @brief Function for multiplication operation.
1140 inline APInt mul(const APInt& LHS, const APInt& RHS) {
1144 /// Performs addition on APInt values.
1145 /// @brief Function for addition operation.
1146 inline APInt add(const APInt& LHS, const APInt& RHS) {
1150 /// Performs subtraction on APInt values.
1151 /// @brief Function for subtraction operation.
1152 inline APInt sub(const APInt& LHS, const APInt& RHS) {
1156 /// Performs bitwise AND operation on APInt LHS and
1158 /// @brief Bitwise AND function for APInt.
1159 inline APInt And(const APInt& LHS, const APInt& RHS) {
1163 /// Performs bitwise OR operation on APInt LHS and APInt RHS.
1164 /// @brief Bitwise OR function for APInt.
1165 inline APInt Or(const APInt& LHS, const APInt& RHS) {
1169 /// Performs bitwise XOR operation on APInt.
1170 /// @brief Bitwise XOR function for APInt.
1171 inline APInt Xor(const APInt& LHS, const APInt& RHS) {
1175 /// Performs a bitwise complement operation on APInt.
1176 /// @brief Bitwise complement function.
1177 inline APInt Not(const APInt& APIVal) {
1181 } // End of APIntOps namespace
1183 } // End of llvm namespace