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0001 //===-- llvm/ADT/APInt.h - For Arbitrary Precision Integer -----*- C++ -*--===//
0002 //
0003 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0004 // See https://llvm.org/LICENSE.txt for license information.
0005 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0006 //
0007 //===----------------------------------------------------------------------===//
0008 ///
0009 /// \file
0010 /// This file implements a class to represent arbitrary precision
0011 /// integral constant values and operations on them.
0012 ///
0013 //===----------------------------------------------------------------------===//
0014 
0015 #ifndef LLVM_ADT_APINT_H
0016 #define LLVM_ADT_APINT_H
0017 
0018 #include "llvm/Support/Compiler.h"
0019 #include "llvm/Support/MathExtras.h"
0020 #include "llvm/Support/float128.h"
0021 #include <cassert>
0022 #include <climits>
0023 #include <cstring>
0024 #include <optional>
0025 #include <utility>
0026 
0027 namespace llvm {
0028 class FoldingSetNodeID;
0029 class StringRef;
0030 class hash_code;
0031 class raw_ostream;
0032 struct Align;
0033 class DynamicAPInt;
0034 
0035 template <typename T> class SmallVectorImpl;
0036 template <typename T> class ArrayRef;
0037 template <typename T, typename Enable> struct DenseMapInfo;
0038 
0039 class APInt;
0040 
0041 inline APInt operator-(APInt);
0042 
0043 //===----------------------------------------------------------------------===//
0044 //                              APInt Class
0045 //===----------------------------------------------------------------------===//
0046 
0047 /// Class for arbitrary precision integers.
0048 ///
0049 /// APInt is a functional replacement for common case unsigned integer type like
0050 /// "unsigned", "unsigned long" or "uint64_t", but also allows non-byte-width
0051 /// integer sizes and large integer value types such as 3-bits, 15-bits, or more
0052 /// than 64-bits of precision. APInt provides a variety of arithmetic operators
0053 /// and methods to manipulate integer values of any bit-width. It supports both
0054 /// the typical integer arithmetic and comparison operations as well as bitwise
0055 /// manipulation.
0056 ///
0057 /// The class has several invariants worth noting:
0058 ///   * All bit, byte, and word positions are zero-based.
0059 ///   * Once the bit width is set, it doesn't change except by the Truncate,
0060 ///     SignExtend, or ZeroExtend operations.
0061 ///   * All binary operators must be on APInt instances of the same bit width.
0062 ///     Attempting to use these operators on instances with different bit
0063 ///     widths will yield an assertion.
0064 ///   * The value is stored canonically as an unsigned value. For operations
0065 ///     where it makes a difference, there are both signed and unsigned variants
0066 ///     of the operation. For example, sdiv and udiv. However, because the bit
0067 ///     widths must be the same, operations such as Mul and Add produce the same
0068 ///     results regardless of whether the values are interpreted as signed or
0069 ///     not.
0070 ///   * In general, the class tries to follow the style of computation that LLVM
0071 ///     uses in its IR. This simplifies its use for LLVM.
0072 ///   * APInt supports zero-bit-width values, but operations that require bits
0073 ///     are not defined on it (e.g. you cannot ask for the sign of a zero-bit
0074 ///     integer).  This means that operations like zero extension and logical
0075 ///     shifts are defined, but sign extension and ashr is not.  Zero bit values
0076 ///     compare and hash equal to themselves, and countLeadingZeros returns 0.
0077 ///
0078 class [[nodiscard]] APInt {
0079 public:
0080   typedef uint64_t WordType;
0081 
0082   /// Byte size of a word.
0083   static constexpr unsigned APINT_WORD_SIZE = sizeof(WordType);
0084 
0085   /// Bits in a word.
0086   static constexpr unsigned APINT_BITS_PER_WORD = APINT_WORD_SIZE * CHAR_BIT;
0087 
0088   enum class Rounding {
0089     DOWN,
0090     TOWARD_ZERO,
0091     UP,
0092   };
0093 
0094   static constexpr WordType WORDTYPE_MAX = ~WordType(0);
0095 
0096   /// \name Constructors
0097   /// @{
0098 
0099   /// Create a new APInt of numBits width, initialized as val.
0100   ///
0101   /// If isSigned is true then val is treated as if it were a signed value
0102   /// (i.e. as an int64_t) and the appropriate sign extension to the bit width
0103   /// will be done. Otherwise, no sign extension occurs (high order bits beyond
0104   /// the range of val are zero filled).
0105   ///
0106   /// \param numBits the bit width of the constructed APInt
0107   /// \param val the initial value of the APInt
0108   /// \param isSigned how to treat signedness of val
0109   /// \param implicitTrunc allow implicit truncation of non-zero/sign bits of
0110   ///                      val beyond the range of numBits
0111   APInt(unsigned numBits, uint64_t val, bool isSigned = false,
0112         bool implicitTrunc = false)
0113       : BitWidth(numBits) {
0114     if (!implicitTrunc) {
0115       if (isSigned) {
0116         if (BitWidth == 0) {
0117           assert((val == 0 || val == uint64_t(-1)) &&
0118                  "Value must be 0 or -1 for signed 0-bit APInt");
0119         } else {
0120           assert(llvm::isIntN(BitWidth, val) &&
0121                  "Value is not an N-bit signed value");
0122         }
0123       } else {
0124         if (BitWidth == 0) {
0125           assert(val == 0 && "Value must be zero for unsigned 0-bit APInt");
0126         } else {
0127           assert(llvm::isUIntN(BitWidth, val) &&
0128                  "Value is not an N-bit unsigned value");
0129         }
0130       }
0131     }
0132     if (isSingleWord()) {
0133       U.VAL = val;
0134       if (implicitTrunc || isSigned)
0135         clearUnusedBits();
0136     } else {
0137       initSlowCase(val, isSigned);
0138     }
0139   }
0140 
0141   /// Construct an APInt of numBits width, initialized as bigVal[].
0142   ///
0143   /// Note that bigVal.size() can be smaller or larger than the corresponding
0144   /// bit width but any extraneous bits will be dropped.
0145   ///
0146   /// \param numBits the bit width of the constructed APInt
0147   /// \param bigVal a sequence of words to form the initial value of the APInt
0148   APInt(unsigned numBits, ArrayRef<uint64_t> bigVal);
0149 
0150   /// Equivalent to APInt(numBits, ArrayRef<uint64_t>(bigVal, numWords)), but
0151   /// deprecated because this constructor is prone to ambiguity with the
0152   /// APInt(unsigned, uint64_t, bool) constructor.
0153   ///
0154   /// If this overload is ever deleted, care should be taken to prevent calls
0155   /// from being incorrectly captured by the APInt(unsigned, uint64_t, bool)
0156   /// constructor.
0157   APInt(unsigned numBits, unsigned numWords, const uint64_t bigVal[]);
0158 
0159   /// Construct an APInt from a string representation.
0160   ///
0161   /// This constructor interprets the string \p str in the given radix. The
0162   /// interpretation stops when the first character that is not suitable for the
0163   /// radix is encountered, or the end of the string. Acceptable radix values
0164   /// are 2, 8, 10, 16, and 36. It is an error for the value implied by the
0165   /// string to require more bits than numBits.
0166   ///
0167   /// \param numBits the bit width of the constructed APInt
0168   /// \param str the string to be interpreted
0169   /// \param radix the radix to use for the conversion
0170   APInt(unsigned numBits, StringRef str, uint8_t radix);
0171 
0172   /// Default constructor that creates an APInt with a 1-bit zero value.
0173   explicit APInt() { U.VAL = 0; }
0174 
0175   /// Copy Constructor.
0176   APInt(const APInt &that) : BitWidth(that.BitWidth) {
0177     if (isSingleWord())
0178       U.VAL = that.U.VAL;
0179     else
0180       initSlowCase(that);
0181   }
0182 
0183   /// Move Constructor.
0184   APInt(APInt &&that) : BitWidth(that.BitWidth) {
0185     memcpy(&U, &that.U, sizeof(U));
0186     that.BitWidth = 0;
0187   }
0188 
0189   /// Destructor.
0190   ~APInt() {
0191     if (needsCleanup())
0192       delete[] U.pVal;
0193   }
0194 
0195   /// @}
0196   /// \name Value Generators
0197   /// @{
0198 
0199   /// Get the '0' value for the specified bit-width.
0200   static APInt getZero(unsigned numBits) { return APInt(numBits, 0); }
0201 
0202   /// Return an APInt zero bits wide.
0203   static APInt getZeroWidth() { return getZero(0); }
0204 
0205   /// Gets maximum unsigned value of APInt for specific bit width.
0206   static APInt getMaxValue(unsigned numBits) { return getAllOnes(numBits); }
0207 
0208   /// Gets maximum signed value of APInt for a specific bit width.
0209   static APInt getSignedMaxValue(unsigned numBits) {
0210     APInt API = getAllOnes(numBits);
0211     API.clearBit(numBits - 1);
0212     return API;
0213   }
0214 
0215   /// Gets minimum unsigned value of APInt for a specific bit width.
0216   static APInt getMinValue(unsigned numBits) { return APInt(numBits, 0); }
0217 
0218   /// Gets minimum signed value of APInt for a specific bit width.
0219   static APInt getSignedMinValue(unsigned numBits) {
0220     APInt API(numBits, 0);
0221     API.setBit(numBits - 1);
0222     return API;
0223   }
0224 
0225   /// Get the SignMask for a specific bit width.
0226   ///
0227   /// This is just a wrapper function of getSignedMinValue(), and it helps code
0228   /// readability when we want to get a SignMask.
0229   static APInt getSignMask(unsigned BitWidth) {
0230     return getSignedMinValue(BitWidth);
0231   }
0232 
0233   /// Return an APInt of a specified width with all bits set.
0234   static APInt getAllOnes(unsigned numBits) {
0235     return APInt(numBits, WORDTYPE_MAX, true);
0236   }
0237 
0238   /// Return an APInt with exactly one bit set in the result.
0239   static APInt getOneBitSet(unsigned numBits, unsigned BitNo) {
0240     APInt Res(numBits, 0);
0241     Res.setBit(BitNo);
0242     return Res;
0243   }
0244 
0245   /// Get a value with a block of bits set.
0246   ///
0247   /// Constructs an APInt value that has a contiguous range of bits set. The
0248   /// bits from loBit (inclusive) to hiBit (exclusive) will be set. All other
0249   /// bits will be zero. For example, with parameters(32, 0, 16) you would get
0250   /// 0x0000FFFF. Please call getBitsSetWithWrap if \p loBit may be greater than
0251   /// \p hiBit.
0252   ///
0253   /// \param numBits the intended bit width of the result
0254   /// \param loBit the index of the lowest bit set.
0255   /// \param hiBit the index of the highest bit set.
0256   ///
0257   /// \returns An APInt value with the requested bits set.
0258   static APInt getBitsSet(unsigned numBits, unsigned loBit, unsigned hiBit) {
0259     APInt Res(numBits, 0);
0260     Res.setBits(loBit, hiBit);
0261     return Res;
0262   }
0263 
0264   /// Wrap version of getBitsSet.
0265   /// If \p hiBit is bigger than \p loBit, this is same with getBitsSet.
0266   /// If \p hiBit is not bigger than \p loBit, the set bits "wrap". For example,
0267   /// with parameters (32, 28, 4), you would get 0xF000000F.
0268   /// If \p hiBit is equal to \p loBit, you would get a result with all bits
0269   /// set.
0270   static APInt getBitsSetWithWrap(unsigned numBits, unsigned loBit,
0271                                   unsigned hiBit) {
0272     APInt Res(numBits, 0);
0273     Res.setBitsWithWrap(loBit, hiBit);
0274     return Res;
0275   }
0276 
0277   /// Constructs an APInt value that has a contiguous range of bits set. The
0278   /// bits from loBit (inclusive) to numBits (exclusive) will be set. All other
0279   /// bits will be zero. For example, with parameters(32, 12) you would get
0280   /// 0xFFFFF000.
0281   ///
0282   /// \param numBits the intended bit width of the result
0283   /// \param loBit the index of the lowest bit to set.
0284   ///
0285   /// \returns An APInt value with the requested bits set.
0286   static APInt getBitsSetFrom(unsigned numBits, unsigned loBit) {
0287     APInt Res(numBits, 0);
0288     Res.setBitsFrom(loBit);
0289     return Res;
0290   }
0291 
0292   /// Constructs an APInt value that has the top hiBitsSet bits set.
0293   ///
0294   /// \param numBits the bitwidth of the result
0295   /// \param hiBitsSet the number of high-order bits set in the result.
0296   static APInt getHighBitsSet(unsigned numBits, unsigned hiBitsSet) {
0297     APInt Res(numBits, 0);
0298     Res.setHighBits(hiBitsSet);
0299     return Res;
0300   }
0301 
0302   /// Constructs an APInt value that has the bottom loBitsSet bits set.
0303   ///
0304   /// \param numBits the bitwidth of the result
0305   /// \param loBitsSet the number of low-order bits set in the result.
0306   static APInt getLowBitsSet(unsigned numBits, unsigned loBitsSet) {
0307     APInt Res(numBits, 0);
0308     Res.setLowBits(loBitsSet);
0309     return Res;
0310   }
0311 
0312   /// Return a value containing V broadcasted over NewLen bits.
0313   static APInt getSplat(unsigned NewLen, const APInt &V);
0314 
0315   /// @}
0316   /// \name Value Tests
0317   /// @{
0318 
0319   /// Determine if this APInt just has one word to store value.
0320   ///
0321   /// \returns true if the number of bits <= 64, false otherwise.
0322   bool isSingleWord() const { return BitWidth <= APINT_BITS_PER_WORD; }
0323 
0324   /// Determine sign of this APInt.
0325   ///
0326   /// This tests the high bit of this APInt to determine if it is set.
0327   ///
0328   /// \returns true if this APInt is negative, false otherwise
0329   bool isNegative() const { return (*this)[BitWidth - 1]; }
0330 
0331   /// Determine if this APInt Value is non-negative (>= 0)
0332   ///
0333   /// This tests the high bit of the APInt to determine if it is unset.
0334   bool isNonNegative() const { return !isNegative(); }
0335 
0336   /// Determine if sign bit of this APInt is set.
0337   ///
0338   /// This tests the high bit of this APInt to determine if it is set.
0339   ///
0340   /// \returns true if this APInt has its sign bit set, false otherwise.
0341   bool isSignBitSet() const { return (*this)[BitWidth - 1]; }
0342 
0343   /// Determine if sign bit of this APInt is clear.
0344   ///
0345   /// This tests the high bit of this APInt to determine if it is clear.
0346   ///
0347   /// \returns true if this APInt has its sign bit clear, false otherwise.
0348   bool isSignBitClear() const { return !isSignBitSet(); }
0349 
0350   /// Determine if this APInt Value is positive.
0351   ///
0352   /// This tests if the value of this APInt is positive (> 0). Note
0353   /// that 0 is not a positive value.
0354   ///
0355   /// \returns true if this APInt is positive.
0356   bool isStrictlyPositive() const { return isNonNegative() && !isZero(); }
0357 
0358   /// Determine if this APInt Value is non-positive (<= 0).
0359   ///
0360   /// \returns true if this APInt is non-positive.
0361   bool isNonPositive() const { return !isStrictlyPositive(); }
0362 
0363   /// Determine if this APInt Value only has the specified bit set.
0364   ///
0365   /// \returns true if this APInt only has the specified bit set.
0366   bool isOneBitSet(unsigned BitNo) const {
0367     return (*this)[BitNo] && popcount() == 1;
0368   }
0369 
0370   /// Determine if all bits are set.  This is true for zero-width values.
0371   bool isAllOnes() const {
0372     if (BitWidth == 0)
0373       return true;
0374     if (isSingleWord())
0375       return U.VAL == WORDTYPE_MAX >> (APINT_BITS_PER_WORD - BitWidth);
0376     return countTrailingOnesSlowCase() == BitWidth;
0377   }
0378 
0379   /// Determine if this value is zero, i.e. all bits are clear.
0380   bool isZero() const {
0381     if (isSingleWord())
0382       return U.VAL == 0;
0383     return countLeadingZerosSlowCase() == BitWidth;
0384   }
0385 
0386   /// Determine if this is a value of 1.
0387   ///
0388   /// This checks to see if the value of this APInt is one.
0389   bool isOne() const {
0390     if (isSingleWord())
0391       return U.VAL == 1;
0392     return countLeadingZerosSlowCase() == BitWidth - 1;
0393   }
0394 
0395   /// Determine if this is the largest unsigned value.
0396   ///
0397   /// This checks to see if the value of this APInt is the maximum unsigned
0398   /// value for the APInt's bit width.
0399   bool isMaxValue() const { return isAllOnes(); }
0400 
0401   /// Determine if this is the largest signed value.
0402   ///
0403   /// This checks to see if the value of this APInt is the maximum signed
0404   /// value for the APInt's bit width.
0405   bool isMaxSignedValue() const {
0406     if (isSingleWord()) {
0407       assert(BitWidth && "zero width values not allowed");
0408       return U.VAL == ((WordType(1) << (BitWidth - 1)) - 1);
0409     }
0410     return !isNegative() && countTrailingOnesSlowCase() == BitWidth - 1;
0411   }
0412 
0413   /// Determine if this is the smallest unsigned value.
0414   ///
0415   /// This checks to see if the value of this APInt is the minimum unsigned
0416   /// value for the APInt's bit width.
0417   bool isMinValue() const { return isZero(); }
0418 
0419   /// Determine if this is the smallest signed value.
0420   ///
0421   /// This checks to see if the value of this APInt is the minimum signed
0422   /// value for the APInt's bit width.
0423   bool isMinSignedValue() const {
0424     if (isSingleWord()) {
0425       assert(BitWidth && "zero width values not allowed");
0426       return U.VAL == (WordType(1) << (BitWidth - 1));
0427     }
0428     return isNegative() && countTrailingZerosSlowCase() == BitWidth - 1;
0429   }
0430 
0431   /// Check if this APInt has an N-bits unsigned integer value.
0432   bool isIntN(unsigned N) const { return getActiveBits() <= N; }
0433 
0434   /// Check if this APInt has an N-bits signed integer value.
0435   bool isSignedIntN(unsigned N) const { return getSignificantBits() <= N; }
0436 
0437   /// Check if this APInt's value is a power of two greater than zero.
0438   ///
0439   /// \returns true if the argument APInt value is a power of two > 0.
0440   bool isPowerOf2() const {
0441     if (isSingleWord()) {
0442       assert(BitWidth && "zero width values not allowed");
0443       return isPowerOf2_64(U.VAL);
0444     }
0445     return countPopulationSlowCase() == 1;
0446   }
0447 
0448   /// Check if this APInt's negated value is a power of two greater than zero.
0449   bool isNegatedPowerOf2() const {
0450     assert(BitWidth && "zero width values not allowed");
0451     if (isNonNegative())
0452       return false;
0453     // NegatedPowerOf2 - shifted mask in the top bits.
0454     unsigned LO = countl_one();
0455     unsigned TZ = countr_zero();
0456     return (LO + TZ) == BitWidth;
0457   }
0458 
0459   /// Checks if this APInt -interpreted as an address- is aligned to the
0460   /// provided value.
0461   bool isAligned(Align A) const;
0462 
0463   /// Check if the APInt's value is returned by getSignMask.
0464   ///
0465   /// \returns true if this is the value returned by getSignMask.
0466   bool isSignMask() const { return isMinSignedValue(); }
0467 
0468   /// Convert APInt to a boolean value.
0469   ///
0470   /// This converts the APInt to a boolean value as a test against zero.
0471   bool getBoolValue() const { return !isZero(); }
0472 
0473   /// If this value is smaller than the specified limit, return it, otherwise
0474   /// return the limit value.  This causes the value to saturate to the limit.
0475   uint64_t getLimitedValue(uint64_t Limit = UINT64_MAX) const {
0476     return ugt(Limit) ? Limit : getZExtValue();
0477   }
0478 
0479   /// Check if the APInt consists of a repeated bit pattern.
0480   ///
0481   /// e.g. 0x01010101 satisfies isSplat(8).
0482   /// \param SplatSizeInBits The size of the pattern in bits. Must divide bit
0483   /// width without remainder.
0484   bool isSplat(unsigned SplatSizeInBits) const;
0485 
0486   /// \returns true if this APInt value is a sequence of \param numBits ones
0487   /// starting at the least significant bit with the remainder zero.
0488   bool isMask(unsigned numBits) const {
0489     assert(numBits != 0 && "numBits must be non-zero");
0490     assert(numBits <= BitWidth && "numBits out of range");
0491     if (isSingleWord())
0492       return U.VAL == (WORDTYPE_MAX >> (APINT_BITS_PER_WORD - numBits));
0493     unsigned Ones = countTrailingOnesSlowCase();
0494     return (numBits == Ones) &&
0495            ((Ones + countLeadingZerosSlowCase()) == BitWidth);
0496   }
0497 
0498   /// \returns true if this APInt is a non-empty sequence of ones starting at
0499   /// the least significant bit with the remainder zero.
0500   /// Ex. isMask(0x0000FFFFU) == true.
0501   bool isMask() const {
0502     if (isSingleWord())
0503       return isMask_64(U.VAL);
0504     unsigned Ones = countTrailingOnesSlowCase();
0505     return (Ones > 0) && ((Ones + countLeadingZerosSlowCase()) == BitWidth);
0506   }
0507 
0508   /// Return true if this APInt value contains a non-empty sequence of ones with
0509   /// the remainder zero.
0510   bool isShiftedMask() const {
0511     if (isSingleWord())
0512       return isShiftedMask_64(U.VAL);
0513     unsigned Ones = countPopulationSlowCase();
0514     unsigned LeadZ = countLeadingZerosSlowCase();
0515     return (Ones + LeadZ + countTrailingZerosSlowCase()) == BitWidth;
0516   }
0517 
0518   /// Return true if this APInt value contains a non-empty sequence of ones with
0519   /// the remainder zero. If true, \p MaskIdx will specify the index of the
0520   /// lowest set bit and \p MaskLen is updated to specify the length of the
0521   /// mask, else neither are updated.
0522   bool isShiftedMask(unsigned &MaskIdx, unsigned &MaskLen) const {
0523     if (isSingleWord())
0524       return isShiftedMask_64(U.VAL, MaskIdx, MaskLen);
0525     unsigned Ones = countPopulationSlowCase();
0526     unsigned LeadZ = countLeadingZerosSlowCase();
0527     unsigned TrailZ = countTrailingZerosSlowCase();
0528     if ((Ones + LeadZ + TrailZ) != BitWidth)
0529       return false;
0530     MaskLen = Ones;
0531     MaskIdx = TrailZ;
0532     return true;
0533   }
0534 
0535   /// Compute an APInt containing numBits highbits from this APInt.
0536   ///
0537   /// Get an APInt with the same BitWidth as this APInt, just zero mask the low
0538   /// bits and right shift to the least significant bit.
0539   ///
0540   /// \returns the high "numBits" bits of this APInt.
0541   APInt getHiBits(unsigned numBits) const;
0542 
0543   /// Compute an APInt containing numBits lowbits from this APInt.
0544   ///
0545   /// Get an APInt with the same BitWidth as this APInt, just zero mask the high
0546   /// bits.
0547   ///
0548   /// \returns the low "numBits" bits of this APInt.
0549   APInt getLoBits(unsigned numBits) const;
0550 
0551   /// Determine if two APInts have the same value, after zero-extending
0552   /// one of them (if needed!) to ensure that the bit-widths match.
0553   static bool isSameValue(const APInt &I1, const APInt &I2) {
0554     if (I1.getBitWidth() == I2.getBitWidth())
0555       return I1 == I2;
0556 
0557     if (I1.getBitWidth() > I2.getBitWidth())
0558       return I1 == I2.zext(I1.getBitWidth());
0559 
0560     return I1.zext(I2.getBitWidth()) == I2;
0561   }
0562 
0563   /// Overload to compute a hash_code for an APInt value.
0564   friend hash_code hash_value(const APInt &Arg);
0565 
0566   /// This function returns a pointer to the internal storage of the APInt.
0567   /// This is useful for writing out the APInt in binary form without any
0568   /// conversions.
0569   const uint64_t *getRawData() const {
0570     if (isSingleWord())
0571       return &U.VAL;
0572     return &U.pVal[0];
0573   }
0574 
0575   /// @}
0576   /// \name Unary Operators
0577   /// @{
0578 
0579   /// Postfix increment operator.  Increment *this by 1.
0580   ///
0581   /// \returns a new APInt value representing the original value of *this.
0582   APInt operator++(int) {
0583     APInt API(*this);
0584     ++(*this);
0585     return API;
0586   }
0587 
0588   /// Prefix increment operator.
0589   ///
0590   /// \returns *this incremented by one
0591   APInt &operator++();
0592 
0593   /// Postfix decrement operator. Decrement *this by 1.
0594   ///
0595   /// \returns a new APInt value representing the original value of *this.
0596   APInt operator--(int) {
0597     APInt API(*this);
0598     --(*this);
0599     return API;
0600   }
0601 
0602   /// Prefix decrement operator.
0603   ///
0604   /// \returns *this decremented by one.
0605   APInt &operator--();
0606 
0607   /// Logical negation operation on this APInt returns true if zero, like normal
0608   /// integers.
0609   bool operator!() const { return isZero(); }
0610 
0611   /// @}
0612   /// \name Assignment Operators
0613   /// @{
0614 
0615   /// Copy assignment operator.
0616   ///
0617   /// \returns *this after assignment of RHS.
0618   APInt &operator=(const APInt &RHS) {
0619     // The common case (both source or dest being inline) doesn't require
0620     // allocation or deallocation.
0621     if (isSingleWord() && RHS.isSingleWord()) {
0622       U.VAL = RHS.U.VAL;
0623       BitWidth = RHS.BitWidth;
0624       return *this;
0625     }
0626 
0627     assignSlowCase(RHS);
0628     return *this;
0629   }
0630 
0631   /// Move assignment operator.
0632   APInt &operator=(APInt &&that) {
0633 #ifdef EXPENSIVE_CHECKS
0634     // Some std::shuffle implementations still do self-assignment.
0635     if (this == &that)
0636       return *this;
0637 #endif
0638     assert(this != &that && "Self-move not supported");
0639     if (!isSingleWord())
0640       delete[] U.pVal;
0641 
0642     // Use memcpy so that type based alias analysis sees both VAL and pVal
0643     // as modified.
0644     memcpy(&U, &that.U, sizeof(U));
0645 
0646     BitWidth = that.BitWidth;
0647     that.BitWidth = 0;
0648     return *this;
0649   }
0650 
0651   /// Assignment operator.
0652   ///
0653   /// The RHS value is assigned to *this. If the significant bits in RHS exceed
0654   /// the bit width, the excess bits are truncated. If the bit width is larger
0655   /// than 64, the value is zero filled in the unspecified high order bits.
0656   ///
0657   /// \returns *this after assignment of RHS value.
0658   APInt &operator=(uint64_t RHS) {
0659     if (isSingleWord()) {
0660       U.VAL = RHS;
0661       return clearUnusedBits();
0662     }
0663     U.pVal[0] = RHS;
0664     memset(U.pVal + 1, 0, (getNumWords() - 1) * APINT_WORD_SIZE);
0665     return *this;
0666   }
0667 
0668   /// Bitwise AND assignment operator.
0669   ///
0670   /// Performs a bitwise AND operation on this APInt and RHS. The result is
0671   /// assigned to *this.
0672   ///
0673   /// \returns *this after ANDing with RHS.
0674   APInt &operator&=(const APInt &RHS) {
0675     assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
0676     if (isSingleWord())
0677       U.VAL &= RHS.U.VAL;
0678     else
0679       andAssignSlowCase(RHS);
0680     return *this;
0681   }
0682 
0683   /// Bitwise AND assignment operator.
0684   ///
0685   /// Performs a bitwise AND operation on this APInt and RHS. RHS is
0686   /// logically zero-extended or truncated to match the bit-width of
0687   /// the LHS.
0688   APInt &operator&=(uint64_t RHS) {
0689     if (isSingleWord()) {
0690       U.VAL &= RHS;
0691       return *this;
0692     }
0693     U.pVal[0] &= RHS;
0694     memset(U.pVal + 1, 0, (getNumWords() - 1) * APINT_WORD_SIZE);
0695     return *this;
0696   }
0697 
0698   /// Bitwise OR assignment operator.
0699   ///
0700   /// Performs a bitwise OR operation on this APInt and RHS. The result is
0701   /// assigned *this;
0702   ///
0703   /// \returns *this after ORing with RHS.
0704   APInt &operator|=(const APInt &RHS) {
0705     assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
0706     if (isSingleWord())
0707       U.VAL |= RHS.U.VAL;
0708     else
0709       orAssignSlowCase(RHS);
0710     return *this;
0711   }
0712 
0713   /// Bitwise OR assignment operator.
0714   ///
0715   /// Performs a bitwise OR operation on this APInt and RHS. RHS is
0716   /// logically zero-extended or truncated to match the bit-width of
0717   /// the LHS.
0718   APInt &operator|=(uint64_t RHS) {
0719     if (isSingleWord()) {
0720       U.VAL |= RHS;
0721       return clearUnusedBits();
0722     }
0723     U.pVal[0] |= RHS;
0724     return *this;
0725   }
0726 
0727   /// Bitwise XOR assignment operator.
0728   ///
0729   /// Performs a bitwise XOR operation on this APInt and RHS. The result is
0730   /// assigned to *this.
0731   ///
0732   /// \returns *this after XORing with RHS.
0733   APInt &operator^=(const APInt &RHS) {
0734     assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
0735     if (isSingleWord())
0736       U.VAL ^= RHS.U.VAL;
0737     else
0738       xorAssignSlowCase(RHS);
0739     return *this;
0740   }
0741 
0742   /// Bitwise XOR assignment operator.
0743   ///
0744   /// Performs a bitwise XOR operation on this APInt and RHS. RHS is
0745   /// logically zero-extended or truncated to match the bit-width of
0746   /// the LHS.
0747   APInt &operator^=(uint64_t RHS) {
0748     if (isSingleWord()) {
0749       U.VAL ^= RHS;
0750       return clearUnusedBits();
0751     }
0752     U.pVal[0] ^= RHS;
0753     return *this;
0754   }
0755 
0756   /// Multiplication assignment operator.
0757   ///
0758   /// Multiplies this APInt by RHS and assigns the result to *this.
0759   ///
0760   /// \returns *this
0761   APInt &operator*=(const APInt &RHS);
0762   APInt &operator*=(uint64_t RHS);
0763 
0764   /// Addition assignment operator.
0765   ///
0766   /// Adds RHS to *this and assigns the result to *this.
0767   ///
0768   /// \returns *this
0769   APInt &operator+=(const APInt &RHS);
0770   APInt &operator+=(uint64_t RHS);
0771 
0772   /// Subtraction assignment operator.
0773   ///
0774   /// Subtracts RHS from *this and assigns the result to *this.
0775   ///
0776   /// \returns *this
0777   APInt &operator-=(const APInt &RHS);
0778   APInt &operator-=(uint64_t RHS);
0779 
0780   /// Left-shift assignment function.
0781   ///
0782   /// Shifts *this left by shiftAmt and assigns the result to *this.
0783   ///
0784   /// \returns *this after shifting left by ShiftAmt
0785   APInt &operator<<=(unsigned ShiftAmt) {
0786     assert(ShiftAmt <= BitWidth && "Invalid shift amount");
0787     if (isSingleWord()) {
0788       if (ShiftAmt == BitWidth)
0789         U.VAL = 0;
0790       else
0791         U.VAL <<= ShiftAmt;
0792       return clearUnusedBits();
0793     }
0794     shlSlowCase(ShiftAmt);
0795     return *this;
0796   }
0797 
0798   /// Left-shift assignment function.
0799   ///
0800   /// Shifts *this left by shiftAmt and assigns the result to *this.
0801   ///
0802   /// \returns *this after shifting left by ShiftAmt
0803   APInt &operator<<=(const APInt &ShiftAmt);
0804 
0805   /// @}
0806   /// \name Binary Operators
0807   /// @{
0808 
0809   /// Multiplication operator.
0810   ///
0811   /// Multiplies this APInt by RHS and returns the result.
0812   APInt operator*(const APInt &RHS) const;
0813 
0814   /// Left logical shift operator.
0815   ///
0816   /// Shifts this APInt left by \p Bits and returns the result.
0817   APInt operator<<(unsigned Bits) const { return shl(Bits); }
0818 
0819   /// Left logical shift operator.
0820   ///
0821   /// Shifts this APInt left by \p Bits and returns the result.
0822   APInt operator<<(const APInt &Bits) const { return shl(Bits); }
0823 
0824   /// Arithmetic right-shift function.
0825   ///
0826   /// Arithmetic right-shift this APInt by shiftAmt.
0827   APInt ashr(unsigned ShiftAmt) const {
0828     APInt R(*this);
0829     R.ashrInPlace(ShiftAmt);
0830     return R;
0831   }
0832 
0833   /// Arithmetic right-shift this APInt by ShiftAmt in place.
0834   void ashrInPlace(unsigned ShiftAmt) {
0835     assert(ShiftAmt <= BitWidth && "Invalid shift amount");
0836     if (isSingleWord()) {
0837       int64_t SExtVAL = SignExtend64(U.VAL, BitWidth);
0838       if (ShiftAmt == BitWidth)
0839         U.VAL = SExtVAL >> (APINT_BITS_PER_WORD - 1); // Fill with sign bit.
0840       else
0841         U.VAL = SExtVAL >> ShiftAmt;
0842       clearUnusedBits();
0843       return;
0844     }
0845     ashrSlowCase(ShiftAmt);
0846   }
0847 
0848   /// Logical right-shift function.
0849   ///
0850   /// Logical right-shift this APInt by shiftAmt.
0851   APInt lshr(unsigned shiftAmt) const {
0852     APInt R(*this);
0853     R.lshrInPlace(shiftAmt);
0854     return R;
0855   }
0856 
0857   /// Logical right-shift this APInt by ShiftAmt in place.
0858   void lshrInPlace(unsigned ShiftAmt) {
0859     assert(ShiftAmt <= BitWidth && "Invalid shift amount");
0860     if (isSingleWord()) {
0861       if (ShiftAmt == BitWidth)
0862         U.VAL = 0;
0863       else
0864         U.VAL >>= ShiftAmt;
0865       return;
0866     }
0867     lshrSlowCase(ShiftAmt);
0868   }
0869 
0870   /// Left-shift function.
0871   ///
0872   /// Left-shift this APInt by shiftAmt.
0873   APInt shl(unsigned shiftAmt) const {
0874     APInt R(*this);
0875     R <<= shiftAmt;
0876     return R;
0877   }
0878 
0879   /// relative logical shift right
0880   APInt relativeLShr(int RelativeShift) const {
0881     return RelativeShift > 0 ? lshr(RelativeShift) : shl(-RelativeShift);
0882   }
0883 
0884   /// relative logical shift left
0885   APInt relativeLShl(int RelativeShift) const {
0886     return relativeLShr(-RelativeShift);
0887   }
0888 
0889   /// relative arithmetic shift right
0890   APInt relativeAShr(int RelativeShift) const {
0891     return RelativeShift > 0 ? ashr(RelativeShift) : shl(-RelativeShift);
0892   }
0893 
0894   /// relative arithmetic shift left
0895   APInt relativeAShl(int RelativeShift) const {
0896     return relativeAShr(-RelativeShift);
0897   }
0898 
0899   /// Rotate left by rotateAmt.
0900   APInt rotl(unsigned rotateAmt) const;
0901 
0902   /// Rotate right by rotateAmt.
0903   APInt rotr(unsigned rotateAmt) const;
0904 
0905   /// Arithmetic right-shift function.
0906   ///
0907   /// Arithmetic right-shift this APInt by shiftAmt.
0908   APInt ashr(const APInt &ShiftAmt) const {
0909     APInt R(*this);
0910     R.ashrInPlace(ShiftAmt);
0911     return R;
0912   }
0913 
0914   /// Arithmetic right-shift this APInt by shiftAmt in place.
0915   void ashrInPlace(const APInt &shiftAmt);
0916 
0917   /// Logical right-shift function.
0918   ///
0919   /// Logical right-shift this APInt by shiftAmt.
0920   APInt lshr(const APInt &ShiftAmt) const {
0921     APInt R(*this);
0922     R.lshrInPlace(ShiftAmt);
0923     return R;
0924   }
0925 
0926   /// Logical right-shift this APInt by ShiftAmt in place.
0927   void lshrInPlace(const APInt &ShiftAmt);
0928 
0929   /// Left-shift function.
0930   ///
0931   /// Left-shift this APInt by shiftAmt.
0932   APInt shl(const APInt &ShiftAmt) const {
0933     APInt R(*this);
0934     R <<= ShiftAmt;
0935     return R;
0936   }
0937 
0938   /// Rotate left by rotateAmt.
0939   APInt rotl(const APInt &rotateAmt) const;
0940 
0941   /// Rotate right by rotateAmt.
0942   APInt rotr(const APInt &rotateAmt) const;
0943 
0944   /// Concatenate the bits from "NewLSB" onto the bottom of *this.  This is
0945   /// equivalent to:
0946   ///   (this->zext(NewWidth) << NewLSB.getBitWidth()) | NewLSB.zext(NewWidth)
0947   APInt concat(const APInt &NewLSB) const {
0948     /// If the result will be small, then both the merged values are small.
0949     unsigned NewWidth = getBitWidth() + NewLSB.getBitWidth();
0950     if (NewWidth <= APINT_BITS_PER_WORD)
0951       return APInt(NewWidth, (U.VAL << NewLSB.getBitWidth()) | NewLSB.U.VAL);
0952     return concatSlowCase(NewLSB);
0953   }
0954 
0955   /// Unsigned division operation.
0956   ///
0957   /// Perform an unsigned divide operation on this APInt by RHS. Both this and
0958   /// RHS are treated as unsigned quantities for purposes of this division.
0959   ///
0960   /// \returns a new APInt value containing the division result, rounded towards
0961   /// zero.
0962   APInt udiv(const APInt &RHS) const;
0963   APInt udiv(uint64_t RHS) const;
0964 
0965   /// Signed division function for APInt.
0966   ///
0967   /// Signed divide this APInt by APInt RHS.
0968   ///
0969   /// The result is rounded towards zero.
0970   APInt sdiv(const APInt &RHS) const;
0971   APInt sdiv(int64_t RHS) const;
0972 
0973   /// Unsigned remainder operation.
0974   ///
0975   /// Perform an unsigned remainder operation on this APInt with RHS being the
0976   /// divisor. Both this and RHS are treated as unsigned quantities for purposes
0977   /// of this operation.
0978   ///
0979   /// \returns a new APInt value containing the remainder result
0980   APInt urem(const APInt &RHS) const;
0981   uint64_t urem(uint64_t RHS) const;
0982 
0983   /// Function for signed remainder operation.
0984   ///
0985   /// Signed remainder operation on APInt.
0986   ///
0987   /// Note that this is a true remainder operation and not a modulo operation
0988   /// because the sign follows the sign of the dividend which is *this.
0989   APInt srem(const APInt &RHS) const;
0990   int64_t srem(int64_t RHS) const;
0991 
0992   /// Dual division/remainder interface.
0993   ///
0994   /// Sometimes it is convenient to divide two APInt values and obtain both the
0995   /// quotient and remainder. This function does both operations in the same
0996   /// computation making it a little more efficient. The pair of input arguments
0997   /// may overlap with the pair of output arguments. It is safe to call
0998   /// udivrem(X, Y, X, Y), for example.
0999   static void udivrem(const APInt &LHS, const APInt &RHS, APInt &Quotient,
1000                       APInt &Remainder);
1001   static void udivrem(const APInt &LHS, uint64_t RHS, APInt &Quotient,
1002                       uint64_t &Remainder);
1003 
1004   static void sdivrem(const APInt &LHS, const APInt &RHS, APInt &Quotient,
1005                       APInt &Remainder);
1006   static void sdivrem(const APInt &LHS, int64_t RHS, APInt &Quotient,
1007                       int64_t &Remainder);
1008 
1009   // Operations that return overflow indicators.
1010   APInt sadd_ov(const APInt &RHS, bool &Overflow) const;
1011   APInt uadd_ov(const APInt &RHS, bool &Overflow) const;
1012   APInt ssub_ov(const APInt &RHS, bool &Overflow) const;
1013   APInt usub_ov(const APInt &RHS, bool &Overflow) const;
1014   APInt sdiv_ov(const APInt &RHS, bool &Overflow) const;
1015   APInt smul_ov(const APInt &RHS, bool &Overflow) const;
1016   APInt umul_ov(const APInt &RHS, bool &Overflow) const;
1017   APInt sshl_ov(const APInt &Amt, bool &Overflow) const;
1018   APInt sshl_ov(unsigned Amt, bool &Overflow) const;
1019   APInt ushl_ov(const APInt &Amt, bool &Overflow) const;
1020   APInt ushl_ov(unsigned Amt, bool &Overflow) const;
1021 
1022   /// Signed integer floor division operation.
1023   ///
1024   /// Rounds towards negative infinity, i.e. 5 / -2 = -3. Iff minimum value
1025   /// divided by -1 set Overflow to true.
1026   APInt sfloordiv_ov(const APInt &RHS, bool &Overflow) const;
1027 
1028   // Operations that saturate
1029   APInt sadd_sat(const APInt &RHS) const;
1030   APInt uadd_sat(const APInt &RHS) const;
1031   APInt ssub_sat(const APInt &RHS) const;
1032   APInt usub_sat(const APInt &RHS) const;
1033   APInt smul_sat(const APInt &RHS) const;
1034   APInt umul_sat(const APInt &RHS) const;
1035   APInt sshl_sat(const APInt &RHS) const;
1036   APInt sshl_sat(unsigned RHS) const;
1037   APInt ushl_sat(const APInt &RHS) const;
1038   APInt ushl_sat(unsigned RHS) const;
1039 
1040   /// Array-indexing support.
1041   ///
1042   /// \returns the bit value at bitPosition
1043   bool operator[](unsigned bitPosition) const {
1044     assert(bitPosition < getBitWidth() && "Bit position out of bounds!");
1045     return (maskBit(bitPosition) & getWord(bitPosition)) != 0;
1046   }
1047 
1048   /// @}
1049   /// \name Comparison Operators
1050   /// @{
1051 
1052   /// Equality operator.
1053   ///
1054   /// Compares this APInt with RHS for the validity of the equality
1055   /// relationship.
1056   bool operator==(const APInt &RHS) const {
1057     assert(BitWidth == RHS.BitWidth && "Comparison requires equal bit widths");
1058     if (isSingleWord())
1059       return U.VAL == RHS.U.VAL;
1060     return equalSlowCase(RHS);
1061   }
1062 
1063   /// Equality operator.
1064   ///
1065   /// Compares this APInt with a uint64_t for the validity of the equality
1066   /// relationship.
1067   ///
1068   /// \returns true if *this == Val
1069   bool operator==(uint64_t Val) const {
1070     return (isSingleWord() || getActiveBits() <= 64) && getZExtValue() == Val;
1071   }
1072 
1073   /// Equality comparison.
1074   ///
1075   /// Compares this APInt with RHS for the validity of the equality
1076   /// relationship.
1077   ///
1078   /// \returns true if *this == Val
1079   bool eq(const APInt &RHS) const { return (*this) == RHS; }
1080 
1081   /// Inequality operator.
1082   ///
1083   /// Compares this APInt with RHS for the validity of the inequality
1084   /// relationship.
1085   ///
1086   /// \returns true if *this != Val
1087   bool operator!=(const APInt &RHS) const { return !((*this) == RHS); }
1088 
1089   /// Inequality operator.
1090   ///
1091   /// Compares this APInt with a uint64_t for the validity of the inequality
1092   /// relationship.
1093   ///
1094   /// \returns true if *this != Val
1095   bool operator!=(uint64_t Val) const { return !((*this) == Val); }
1096 
1097   /// Inequality comparison
1098   ///
1099   /// Compares this APInt with RHS for the validity of the inequality
1100   /// relationship.
1101   ///
1102   /// \returns true if *this != Val
1103   bool ne(const APInt &RHS) const { return !((*this) == RHS); }
1104 
1105   /// Unsigned less than comparison
1106   ///
1107   /// Regards both *this and RHS as unsigned quantities and compares them for
1108   /// the validity of the less-than relationship.
1109   ///
1110   /// \returns true if *this < RHS when both are considered unsigned.
1111   bool ult(const APInt &RHS) const { return compare(RHS) < 0; }
1112 
1113   /// Unsigned less than comparison
1114   ///
1115   /// Regards both *this as an unsigned quantity and compares it with RHS for
1116   /// the validity of the less-than relationship.
1117   ///
1118   /// \returns true if *this < RHS when considered unsigned.
1119   bool ult(uint64_t RHS) const {
1120     // Only need to check active bits if not a single word.
1121     return (isSingleWord() || getActiveBits() <= 64) && getZExtValue() < RHS;
1122   }
1123 
1124   /// Signed less than comparison
1125   ///
1126   /// Regards both *this and RHS as signed quantities and compares them for
1127   /// validity of the less-than relationship.
1128   ///
1129   /// \returns true if *this < RHS when both are considered signed.
1130   bool slt(const APInt &RHS) const { return compareSigned(RHS) < 0; }
1131 
1132   /// Signed less than comparison
1133   ///
1134   /// Regards both *this as a signed quantity and compares it with RHS for
1135   /// the validity of the less-than relationship.
1136   ///
1137   /// \returns true if *this < RHS when considered signed.
1138   bool slt(int64_t RHS) const {
1139     return (!isSingleWord() && getSignificantBits() > 64)
1140                ? isNegative()
1141                : getSExtValue() < RHS;
1142   }
1143 
1144   /// Unsigned less or equal comparison
1145   ///
1146   /// Regards both *this and RHS as unsigned quantities and compares them for
1147   /// validity of the less-or-equal relationship.
1148   ///
1149   /// \returns true if *this <= RHS when both are considered unsigned.
1150   bool ule(const APInt &RHS) const { return compare(RHS) <= 0; }
1151 
1152   /// Unsigned less or equal comparison
1153   ///
1154   /// Regards both *this as an unsigned quantity and compares it with RHS for
1155   /// the validity of the less-or-equal relationship.
1156   ///
1157   /// \returns true if *this <= RHS when considered unsigned.
1158   bool ule(uint64_t RHS) const { return !ugt(RHS); }
1159 
1160   /// Signed less or equal comparison
1161   ///
1162   /// Regards both *this and RHS as signed quantities and compares them for
1163   /// validity of the less-or-equal relationship.
1164   ///
1165   /// \returns true if *this <= RHS when both are considered signed.
1166   bool sle(const APInt &RHS) const { return compareSigned(RHS) <= 0; }
1167 
1168   /// Signed less or equal comparison
1169   ///
1170   /// Regards both *this as a signed quantity and compares it with RHS for the
1171   /// validity of the less-or-equal relationship.
1172   ///
1173   /// \returns true if *this <= RHS when considered signed.
1174   bool sle(uint64_t RHS) const { return !sgt(RHS); }
1175 
1176   /// Unsigned greater than comparison
1177   ///
1178   /// Regards both *this and RHS as unsigned quantities and compares them for
1179   /// the validity of the greater-than relationship.
1180   ///
1181   /// \returns true if *this > RHS when both are considered unsigned.
1182   bool ugt(const APInt &RHS) const { return !ule(RHS); }
1183 
1184   /// Unsigned greater than comparison
1185   ///
1186   /// Regards both *this as an unsigned quantity and compares it with RHS for
1187   /// the validity of the greater-than relationship.
1188   ///
1189   /// \returns true if *this > RHS when considered unsigned.
1190   bool ugt(uint64_t RHS) const {
1191     // Only need to check active bits if not a single word.
1192     return (!isSingleWord() && getActiveBits() > 64) || getZExtValue() > RHS;
1193   }
1194 
1195   /// Signed greater than comparison
1196   ///
1197   /// Regards both *this and RHS as signed quantities and compares them for the
1198   /// validity of the greater-than relationship.
1199   ///
1200   /// \returns true if *this > RHS when both are considered signed.
1201   bool sgt(const APInt &RHS) const { return !sle(RHS); }
1202 
1203   /// Signed greater than comparison
1204   ///
1205   /// Regards both *this as a signed quantity and compares it with RHS for
1206   /// the validity of the greater-than relationship.
1207   ///
1208   /// \returns true if *this > RHS when considered signed.
1209   bool sgt(int64_t RHS) const {
1210     return (!isSingleWord() && getSignificantBits() > 64)
1211                ? !isNegative()
1212                : getSExtValue() > RHS;
1213   }
1214 
1215   /// Unsigned greater or equal comparison
1216   ///
1217   /// Regards both *this and RHS as unsigned quantities and compares them for
1218   /// validity of the greater-or-equal relationship.
1219   ///
1220   /// \returns true if *this >= RHS when both are considered unsigned.
1221   bool uge(const APInt &RHS) const { return !ult(RHS); }
1222 
1223   /// Unsigned greater or equal comparison
1224   ///
1225   /// Regards both *this as an unsigned quantity and compares it with RHS for
1226   /// the validity of the greater-or-equal relationship.
1227   ///
1228   /// \returns true if *this >= RHS when considered unsigned.
1229   bool uge(uint64_t RHS) const { return !ult(RHS); }
1230 
1231   /// Signed greater or equal comparison
1232   ///
1233   /// Regards both *this and RHS as signed quantities and compares them for
1234   /// validity of the greater-or-equal relationship.
1235   ///
1236   /// \returns true if *this >= RHS when both are considered signed.
1237   bool sge(const APInt &RHS) const { return !slt(RHS); }
1238 
1239   /// Signed greater or equal comparison
1240   ///
1241   /// Regards both *this as a signed quantity and compares it with RHS for
1242   /// the validity of the greater-or-equal relationship.
1243   ///
1244   /// \returns true if *this >= RHS when considered signed.
1245   bool sge(int64_t RHS) const { return !slt(RHS); }
1246 
1247   /// This operation tests if there are any pairs of corresponding bits
1248   /// between this APInt and RHS that are both set.
1249   bool intersects(const APInt &RHS) const {
1250     assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
1251     if (isSingleWord())
1252       return (U.VAL & RHS.U.VAL) != 0;
1253     return intersectsSlowCase(RHS);
1254   }
1255 
1256   /// This operation checks that all bits set in this APInt are also set in RHS.
1257   bool isSubsetOf(const APInt &RHS) const {
1258     assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
1259     if (isSingleWord())
1260       return (U.VAL & ~RHS.U.VAL) == 0;
1261     return isSubsetOfSlowCase(RHS);
1262   }
1263 
1264   /// @}
1265   /// \name Resizing Operators
1266   /// @{
1267 
1268   /// Truncate to new width.
1269   ///
1270   /// Truncate the APInt to a specified width. It is an error to specify a width
1271   /// that is greater than the current width.
1272   APInt trunc(unsigned width) const;
1273 
1274   /// Truncate to new width with unsigned saturation.
1275   ///
1276   /// If the APInt, treated as unsigned integer, can be losslessly truncated to
1277   /// the new bitwidth, then return truncated APInt. Else, return max value.
1278   APInt truncUSat(unsigned width) const;
1279 
1280   /// Truncate to new width with signed saturation.
1281   ///
1282   /// If this APInt, treated as signed integer, can be losslessly truncated to
1283   /// the new bitwidth, then return truncated APInt. Else, return either
1284   /// signed min value if the APInt was negative, or signed max value.
1285   APInt truncSSat(unsigned width) const;
1286 
1287   /// Sign extend to a new width.
1288   ///
1289   /// This operation sign extends the APInt to a new width. If the high order
1290   /// bit is set, the fill on the left will be done with 1 bits, otherwise zero.
1291   /// It is an error to specify a width that is less than the
1292   /// current width.
1293   APInt sext(unsigned width) const;
1294 
1295   /// Zero extend to a new width.
1296   ///
1297   /// This operation zero extends the APInt to a new width. The high order bits
1298   /// are filled with 0 bits.  It is an error to specify a width that is less
1299   /// than the current width.
1300   APInt zext(unsigned width) const;
1301 
1302   /// Sign extend or truncate to width
1303   ///
1304   /// Make this APInt have the bit width given by \p width. The value is sign
1305   /// extended, truncated, or left alone to make it that width.
1306   APInt sextOrTrunc(unsigned width) const;
1307 
1308   /// Zero extend or truncate to width
1309   ///
1310   /// Make this APInt have the bit width given by \p width. The value is zero
1311   /// extended, truncated, or left alone to make it that width.
1312   APInt zextOrTrunc(unsigned width) const;
1313 
1314   /// @}
1315   /// \name Bit Manipulation Operators
1316   /// @{
1317 
1318   /// Set every bit to 1.
1319   void setAllBits() {
1320     if (isSingleWord())
1321       U.VAL = WORDTYPE_MAX;
1322     else
1323       // Set all the bits in all the words.
1324       memset(U.pVal, -1, getNumWords() * APINT_WORD_SIZE);
1325     // Clear the unused ones
1326     clearUnusedBits();
1327   }
1328 
1329   /// Set the given bit to 1 whose position is given as "bitPosition".
1330   void setBit(unsigned BitPosition) {
1331     assert(BitPosition < BitWidth && "BitPosition out of range");
1332     WordType Mask = maskBit(BitPosition);
1333     if (isSingleWord())
1334       U.VAL |= Mask;
1335     else
1336       U.pVal[whichWord(BitPosition)] |= Mask;
1337   }
1338 
1339   /// Set the sign bit to 1.
1340   void setSignBit() { setBit(BitWidth - 1); }
1341 
1342   /// Set a given bit to a given value.
1343   void setBitVal(unsigned BitPosition, bool BitValue) {
1344     if (BitValue)
1345       setBit(BitPosition);
1346     else
1347       clearBit(BitPosition);
1348   }
1349 
1350   /// Set the bits from loBit (inclusive) to hiBit (exclusive) to 1.
1351   /// This function handles "wrap" case when \p loBit >= \p hiBit, and calls
1352   /// setBits when \p loBit < \p hiBit.
1353   /// For \p loBit == \p hiBit wrap case, set every bit to 1.
1354   void setBitsWithWrap(unsigned loBit, unsigned hiBit) {
1355     assert(hiBit <= BitWidth && "hiBit out of range");
1356     assert(loBit <= BitWidth && "loBit out of range");
1357     if (loBit < hiBit) {
1358       setBits(loBit, hiBit);
1359       return;
1360     }
1361     setLowBits(hiBit);
1362     setHighBits(BitWidth - loBit);
1363   }
1364 
1365   /// Set the bits from loBit (inclusive) to hiBit (exclusive) to 1.
1366   /// This function handles case when \p loBit <= \p hiBit.
1367   void setBits(unsigned loBit, unsigned hiBit) {
1368     assert(hiBit <= BitWidth && "hiBit out of range");
1369     assert(loBit <= BitWidth && "loBit out of range");
1370     assert(loBit <= hiBit && "loBit greater than hiBit");
1371     if (loBit == hiBit)
1372       return;
1373     if (loBit < APINT_BITS_PER_WORD && hiBit <= APINT_BITS_PER_WORD) {
1374       uint64_t mask = WORDTYPE_MAX >> (APINT_BITS_PER_WORD - (hiBit - loBit));
1375       mask <<= loBit;
1376       if (isSingleWord())
1377         U.VAL |= mask;
1378       else
1379         U.pVal[0] |= mask;
1380     } else {
1381       setBitsSlowCase(loBit, hiBit);
1382     }
1383   }
1384 
1385   /// Set the top bits starting from loBit.
1386   void setBitsFrom(unsigned loBit) { return setBits(loBit, BitWidth); }
1387 
1388   /// Set the bottom loBits bits.
1389   void setLowBits(unsigned loBits) { return setBits(0, loBits); }
1390 
1391   /// Set the top hiBits bits.
1392   void setHighBits(unsigned hiBits) {
1393     return setBits(BitWidth - hiBits, BitWidth);
1394   }
1395 
1396   /// Set every bit to 0.
1397   void clearAllBits() {
1398     if (isSingleWord())
1399       U.VAL = 0;
1400     else
1401       memset(U.pVal, 0, getNumWords() * APINT_WORD_SIZE);
1402   }
1403 
1404   /// Set a given bit to 0.
1405   ///
1406   /// Set the given bit to 0 whose position is given as "bitPosition".
1407   void clearBit(unsigned BitPosition) {
1408     assert(BitPosition < BitWidth && "BitPosition out of range");
1409     WordType Mask = ~maskBit(BitPosition);
1410     if (isSingleWord())
1411       U.VAL &= Mask;
1412     else
1413       U.pVal[whichWord(BitPosition)] &= Mask;
1414   }
1415 
1416   /// Set bottom loBits bits to 0.
1417   void clearLowBits(unsigned loBits) {
1418     assert(loBits <= BitWidth && "More bits than bitwidth");
1419     APInt Keep = getHighBitsSet(BitWidth, BitWidth - loBits);
1420     *this &= Keep;
1421   }
1422 
1423   /// Set top hiBits bits to 0.
1424   void clearHighBits(unsigned hiBits) {
1425     assert(hiBits <= BitWidth && "More bits than bitwidth");
1426     APInt Keep = getLowBitsSet(BitWidth, BitWidth - hiBits);
1427     *this &= Keep;
1428   }
1429 
1430   /// Set the sign bit to 0.
1431   void clearSignBit() { clearBit(BitWidth - 1); }
1432 
1433   /// Toggle every bit to its opposite value.
1434   void flipAllBits() {
1435     if (isSingleWord()) {
1436       U.VAL ^= WORDTYPE_MAX;
1437       clearUnusedBits();
1438     } else {
1439       flipAllBitsSlowCase();
1440     }
1441   }
1442 
1443   /// Toggles a given bit to its opposite value.
1444   ///
1445   /// Toggle a given bit to its opposite value whose position is given
1446   /// as "bitPosition".
1447   void flipBit(unsigned bitPosition);
1448 
1449   /// Negate this APInt in place.
1450   void negate() {
1451     flipAllBits();
1452     ++(*this);
1453   }
1454 
1455   /// Insert the bits from a smaller APInt starting at bitPosition.
1456   void insertBits(const APInt &SubBits, unsigned bitPosition);
1457   void insertBits(uint64_t SubBits, unsigned bitPosition, unsigned numBits);
1458 
1459   /// Return an APInt with the extracted bits [bitPosition,bitPosition+numBits).
1460   APInt extractBits(unsigned numBits, unsigned bitPosition) const;
1461   uint64_t extractBitsAsZExtValue(unsigned numBits, unsigned bitPosition) const;
1462 
1463   /// @}
1464   /// \name Value Characterization Functions
1465   /// @{
1466 
1467   /// Return the number of bits in the APInt.
1468   unsigned getBitWidth() const { return BitWidth; }
1469 
1470   /// Get the number of words.
1471   ///
1472   /// Here one word's bitwidth equals to that of uint64_t.
1473   ///
1474   /// \returns the number of words to hold the integer value of this APInt.
1475   unsigned getNumWords() const { return getNumWords(BitWidth); }
1476 
1477   /// Get the number of words.
1478   ///
1479   /// *NOTE* Here one word's bitwidth equals to that of uint64_t.
1480   ///
1481   /// \returns the number of words to hold the integer value with a given bit
1482   /// width.
1483   static unsigned getNumWords(unsigned BitWidth) {
1484     return ((uint64_t)BitWidth + APINT_BITS_PER_WORD - 1) / APINT_BITS_PER_WORD;
1485   }
1486 
1487   /// Compute the number of active bits in the value
1488   ///
1489   /// This function returns the number of active bits which is defined as the
1490   /// bit width minus the number of leading zeros. This is used in several
1491   /// computations to see how "wide" the value is.
1492   unsigned getActiveBits() const { return BitWidth - countl_zero(); }
1493 
1494   /// Compute the number of active words in the value of this APInt.
1495   ///
1496   /// This is used in conjunction with getActiveData to extract the raw value of
1497   /// the APInt.
1498   unsigned getActiveWords() const {
1499     unsigned numActiveBits = getActiveBits();
1500     return numActiveBits ? whichWord(numActiveBits - 1) + 1 : 1;
1501   }
1502 
1503   /// Get the minimum bit size for this signed APInt
1504   ///
1505   /// Computes the minimum bit width for this APInt while considering it to be a
1506   /// signed (and probably negative) value. If the value is not negative, this
1507   /// function returns the same value as getActiveBits()+1. Otherwise, it
1508   /// returns the smallest bit width that will retain the negative value. For
1509   /// example, -1 can be written as 0b1 or 0xFFFFFFFFFF. 0b1 is shorter and so
1510   /// for -1, this function will always return 1.
1511   unsigned getSignificantBits() const {
1512     return BitWidth - getNumSignBits() + 1;
1513   }
1514 
1515   /// Get zero extended value
1516   ///
1517   /// This method attempts to return the value of this APInt as a zero extended
1518   /// uint64_t. The bitwidth must be <= 64 or the value must fit within a
1519   /// uint64_t. Otherwise an assertion will result.
1520   uint64_t getZExtValue() const {
1521     if (isSingleWord())
1522       return U.VAL;
1523     assert(getActiveBits() <= 64 && "Too many bits for uint64_t");
1524     return U.pVal[0];
1525   }
1526 
1527   /// Get zero extended value if possible
1528   ///
1529   /// This method attempts to return the value of this APInt as a zero extended
1530   /// uint64_t. The bitwidth must be <= 64 or the value must fit within a
1531   /// uint64_t. Otherwise no value is returned.
1532   std::optional<uint64_t> tryZExtValue() const {
1533     return (getActiveBits() <= 64) ? std::optional<uint64_t>(getZExtValue())
1534                                    : std::nullopt;
1535   };
1536 
1537   /// Get sign extended value
1538   ///
1539   /// This method attempts to return the value of this APInt as a sign extended
1540   /// int64_t. The bit width must be <= 64 or the value must fit within an
1541   /// int64_t. Otherwise an assertion will result.
1542   int64_t getSExtValue() const {
1543     if (isSingleWord())
1544       return SignExtend64(U.VAL, BitWidth);
1545     assert(getSignificantBits() <= 64 && "Too many bits for int64_t");
1546     return int64_t(U.pVal[0]);
1547   }
1548 
1549   /// Get sign extended value if possible
1550   ///
1551   /// This method attempts to return the value of this APInt as a sign extended
1552   /// int64_t. The bitwidth must be <= 64 or the value must fit within an
1553   /// int64_t. Otherwise no value is returned.
1554   std::optional<int64_t> trySExtValue() const {
1555     return (getSignificantBits() <= 64) ? std::optional<int64_t>(getSExtValue())
1556                                         : std::nullopt;
1557   };
1558 
1559   /// Get bits required for string value.
1560   ///
1561   /// This method determines how many bits are required to hold the APInt
1562   /// equivalent of the string given by \p str.
1563   static unsigned getBitsNeeded(StringRef str, uint8_t radix);
1564 
1565   /// Get the bits that are sufficient to represent the string value. This may
1566   /// over estimate the amount of bits required, but it does not require
1567   /// parsing the value in the string.
1568   static unsigned getSufficientBitsNeeded(StringRef Str, uint8_t Radix);
1569 
1570   /// The APInt version of std::countl_zero.
1571   ///
1572   /// It counts the number of zeros from the most significant bit to the first
1573   /// one bit.
1574   ///
1575   /// \returns BitWidth if the value is zero, otherwise returns the number of
1576   ///   zeros from the most significant bit to the first one bits.
1577   unsigned countl_zero() const {
1578     if (isSingleWord()) {
1579       unsigned unusedBits = APINT_BITS_PER_WORD - BitWidth;
1580       return llvm::countl_zero(U.VAL) - unusedBits;
1581     }
1582     return countLeadingZerosSlowCase();
1583   }
1584 
1585   unsigned countLeadingZeros() const { return countl_zero(); }
1586 
1587   /// Count the number of leading one bits.
1588   ///
1589   /// This function is an APInt version of std::countl_one. It counts the number
1590   /// of ones from the most significant bit to the first zero bit.
1591   ///
1592   /// \returns 0 if the high order bit is not set, otherwise returns the number
1593   /// of 1 bits from the most significant to the least
1594   unsigned countl_one() const {
1595     if (isSingleWord()) {
1596       if (LLVM_UNLIKELY(BitWidth == 0))
1597         return 0;
1598       return llvm::countl_one(U.VAL << (APINT_BITS_PER_WORD - BitWidth));
1599     }
1600     return countLeadingOnesSlowCase();
1601   }
1602 
1603   unsigned countLeadingOnes() const { return countl_one(); }
1604 
1605   /// Computes the number of leading bits of this APInt that are equal to its
1606   /// sign bit.
1607   unsigned getNumSignBits() const {
1608     return isNegative() ? countl_one() : countl_zero();
1609   }
1610 
1611   /// Count the number of trailing zero bits.
1612   ///
1613   /// This function is an APInt version of std::countr_zero. It counts the
1614   /// number of zeros from the least significant bit to the first set bit.
1615   ///
1616   /// \returns BitWidth if the value is zero, otherwise returns the number of
1617   /// zeros from the least significant bit to the first one bit.
1618   unsigned countr_zero() const {
1619     if (isSingleWord()) {
1620       unsigned TrailingZeros = llvm::countr_zero(U.VAL);
1621       return (TrailingZeros > BitWidth ? BitWidth : TrailingZeros);
1622     }
1623     return countTrailingZerosSlowCase();
1624   }
1625 
1626   unsigned countTrailingZeros() const { return countr_zero(); }
1627 
1628   /// Count the number of trailing one bits.
1629   ///
1630   /// This function is an APInt version of std::countr_one. It counts the number
1631   /// of ones from the least significant bit to the first zero bit.
1632   ///
1633   /// \returns BitWidth if the value is all ones, otherwise returns the number
1634   /// of ones from the least significant bit to the first zero bit.
1635   unsigned countr_one() const {
1636     if (isSingleWord())
1637       return llvm::countr_one(U.VAL);
1638     return countTrailingOnesSlowCase();
1639   }
1640 
1641   unsigned countTrailingOnes() const { return countr_one(); }
1642 
1643   /// Count the number of bits set.
1644   ///
1645   /// This function is an APInt version of std::popcount. It counts the number
1646   /// of 1 bits in the APInt value.
1647   ///
1648   /// \returns 0 if the value is zero, otherwise returns the number of set bits.
1649   unsigned popcount() const {
1650     if (isSingleWord())
1651       return llvm::popcount(U.VAL);
1652     return countPopulationSlowCase();
1653   }
1654 
1655   /// @}
1656   /// \name Conversion Functions
1657   /// @{
1658   void print(raw_ostream &OS, bool isSigned) const;
1659 
1660   /// Converts an APInt to a string and append it to Str.  Str is commonly a
1661   /// SmallString. If Radix > 10, UpperCase determine the case of letter
1662   /// digits.
1663   void toString(SmallVectorImpl<char> &Str, unsigned Radix, bool Signed,
1664                 bool formatAsCLiteral = false, bool UpperCase = true,
1665                 bool InsertSeparators = false) const;
1666 
1667   /// Considers the APInt to be unsigned and converts it into a string in the
1668   /// radix given. The radix can be 2, 8, 10 16, or 36.
1669   void toStringUnsigned(SmallVectorImpl<char> &Str, unsigned Radix = 10) const {
1670     toString(Str, Radix, false, false);
1671   }
1672 
1673   /// Considers the APInt to be signed and converts it into a string in the
1674   /// radix given. The radix can be 2, 8, 10, 16, or 36.
1675   void toStringSigned(SmallVectorImpl<char> &Str, unsigned Radix = 10) const {
1676     toString(Str, Radix, true, false);
1677   }
1678 
1679   /// \returns a byte-swapped representation of this APInt Value.
1680   APInt byteSwap() const;
1681 
1682   /// \returns the value with the bit representation reversed of this APInt
1683   /// Value.
1684   APInt reverseBits() const;
1685 
1686   /// Converts this APInt to a double value.
1687   double roundToDouble(bool isSigned) const;
1688 
1689   /// Converts this unsigned APInt to a double value.
1690   double roundToDouble() const { return roundToDouble(false); }
1691 
1692   /// Converts this signed APInt to a double value.
1693   double signedRoundToDouble() const { return roundToDouble(true); }
1694 
1695   /// Converts APInt bits to a double
1696   ///
1697   /// The conversion does not do a translation from integer to double, it just
1698   /// re-interprets the bits as a double. Note that it is valid to do this on
1699   /// any bit width. Exactly 64 bits will be translated.
1700   double bitsToDouble() const { return llvm::bit_cast<double>(getWord(0)); }
1701 
1702 #ifdef HAS_IEE754_FLOAT128
1703   float128 bitsToQuad() const {
1704     __uint128_t ul = ((__uint128_t)U.pVal[1] << 64) + U.pVal[0];
1705     return llvm::bit_cast<float128>(ul);
1706   }
1707 #endif
1708 
1709   /// Converts APInt bits to a float
1710   ///
1711   /// The conversion does not do a translation from integer to float, it just
1712   /// re-interprets the bits as a float. Note that it is valid to do this on
1713   /// any bit width. Exactly 32 bits will be translated.
1714   float bitsToFloat() const {
1715     return llvm::bit_cast<float>(static_cast<uint32_t>(getWord(0)));
1716   }
1717 
1718   /// Converts a double to APInt bits.
1719   ///
1720   /// The conversion does not do a translation from double to integer, it just
1721   /// re-interprets the bits of the double.
1722   static APInt doubleToBits(double V) {
1723     return APInt(sizeof(double) * CHAR_BIT, llvm::bit_cast<uint64_t>(V));
1724   }
1725 
1726   /// Converts a float to APInt bits.
1727   ///
1728   /// The conversion does not do a translation from float to integer, it just
1729   /// re-interprets the bits of the float.
1730   static APInt floatToBits(float V) {
1731     return APInt(sizeof(float) * CHAR_BIT, llvm::bit_cast<uint32_t>(V));
1732   }
1733 
1734   /// @}
1735   /// \name Mathematics Operations
1736   /// @{
1737 
1738   /// \returns the floor log base 2 of this APInt.
1739   unsigned logBase2() const { return getActiveBits() - 1; }
1740 
1741   /// \returns the ceil log base 2 of this APInt.
1742   unsigned ceilLogBase2() const {
1743     APInt temp(*this);
1744     --temp;
1745     return temp.getActiveBits();
1746   }
1747 
1748   /// \returns the nearest log base 2 of this APInt. Ties round up.
1749   ///
1750   /// NOTE: When we have a BitWidth of 1, we define:
1751   ///
1752   ///   log2(0) = UINT32_MAX
1753   ///   log2(1) = 0
1754   ///
1755   /// to get around any mathematical concerns resulting from
1756   /// referencing 2 in a space where 2 does no exist.
1757   unsigned nearestLogBase2() const;
1758 
1759   /// \returns the log base 2 of this APInt if its an exact power of two, -1
1760   /// otherwise
1761   int32_t exactLogBase2() const {
1762     if (!isPowerOf2())
1763       return -1;
1764     return logBase2();
1765   }
1766 
1767   /// Compute the square root.
1768   APInt sqrt() const;
1769 
1770   /// Get the absolute value.  If *this is < 0 then return -(*this), otherwise
1771   /// *this.  Note that the "most negative" signed number (e.g. -128 for 8 bit
1772   /// wide APInt) is unchanged due to how negation works.
1773   APInt abs() const {
1774     if (isNegative())
1775       return -(*this);
1776     return *this;
1777   }
1778 
1779   /// \returns the multiplicative inverse of an odd APInt modulo 2^BitWidth.
1780   APInt multiplicativeInverse() const;
1781 
1782   /// @}
1783   /// \name Building-block Operations for APInt and APFloat
1784   /// @{
1785 
1786   // These building block operations operate on a representation of arbitrary
1787   // precision, two's-complement, bignum integer values. They should be
1788   // sufficient to implement APInt and APFloat bignum requirements. Inputs are
1789   // generally a pointer to the base of an array of integer parts, representing
1790   // an unsigned bignum, and a count of how many parts there are.
1791 
1792   /// Sets the least significant part of a bignum to the input value, and zeroes
1793   /// out higher parts.
1794   static void tcSet(WordType *, WordType, unsigned);
1795 
1796   /// Assign one bignum to another.
1797   static void tcAssign(WordType *, const WordType *, unsigned);
1798 
1799   /// Returns true if a bignum is zero, false otherwise.
1800   static bool tcIsZero(const WordType *, unsigned);
1801 
1802   /// Extract the given bit of a bignum; returns 0 or 1.  Zero-based.
1803   static int tcExtractBit(const WordType *, unsigned bit);
1804 
1805   /// Copy the bit vector of width srcBITS from SRC, starting at bit srcLSB, to
1806   /// DST, of dstCOUNT parts, such that the bit srcLSB becomes the least
1807   /// significant bit of DST.  All high bits above srcBITS in DST are
1808   /// zero-filled.
1809   static void tcExtract(WordType *, unsigned dstCount, const WordType *,
1810                         unsigned srcBits, unsigned srcLSB);
1811 
1812   /// Set the given bit of a bignum.  Zero-based.
1813   static void tcSetBit(WordType *, unsigned bit);
1814 
1815   /// Clear the given bit of a bignum.  Zero-based.
1816   static void tcClearBit(WordType *, unsigned bit);
1817 
1818   /// Returns the bit number of the least or most significant set bit of a
1819   /// number.  If the input number has no bits set -1U is returned.
1820   static unsigned tcLSB(const WordType *, unsigned n);
1821   static unsigned tcMSB(const WordType *parts, unsigned n);
1822 
1823   /// Negate a bignum in-place.
1824   static void tcNegate(WordType *, unsigned);
1825 
1826   /// DST += RHS + CARRY where CARRY is zero or one.  Returns the carry flag.
1827   static WordType tcAdd(WordType *, const WordType *, WordType carry, unsigned);
1828   /// DST += RHS.  Returns the carry flag.
1829   static WordType tcAddPart(WordType *, WordType, unsigned);
1830 
1831   /// DST -= RHS + CARRY where CARRY is zero or one. Returns the carry flag.
1832   static WordType tcSubtract(WordType *, const WordType *, WordType carry,
1833                              unsigned);
1834   /// DST -= RHS.  Returns the carry flag.
1835   static WordType tcSubtractPart(WordType *, WordType, unsigned);
1836 
1837   /// DST += SRC * MULTIPLIER + PART   if add is true
1838   /// DST  = SRC * MULTIPLIER + PART   if add is false
1839   ///
1840   /// Requires 0 <= DSTPARTS <= SRCPARTS + 1.  If DST overlaps SRC they must
1841   /// start at the same point, i.e. DST == SRC.
1842   ///
1843   /// If DSTPARTS == SRC_PARTS + 1 no overflow occurs and zero is returned.
1844   /// Otherwise DST is filled with the least significant DSTPARTS parts of the
1845   /// result, and if all of the omitted higher parts were zero return zero,
1846   /// otherwise overflow occurred and return one.
1847   static int tcMultiplyPart(WordType *dst, const WordType *src,
1848                             WordType multiplier, WordType carry,
1849                             unsigned srcParts, unsigned dstParts, bool add);
1850 
1851   /// DST = LHS * RHS, where DST has the same width as the operands and is
1852   /// filled with the least significant parts of the result.  Returns one if
1853   /// overflow occurred, otherwise zero.  DST must be disjoint from both
1854   /// operands.
1855   static int tcMultiply(WordType *, const WordType *, const WordType *,
1856                         unsigned);
1857 
1858   /// DST = LHS * RHS, where DST has width the sum of the widths of the
1859   /// operands. No overflow occurs. DST must be disjoint from both operands.
1860   static void tcFullMultiply(WordType *, const WordType *, const WordType *,
1861                              unsigned, unsigned);
1862 
1863   /// If RHS is zero LHS and REMAINDER are left unchanged, return one.
1864   /// Otherwise set LHS to LHS / RHS with the fractional part discarded, set
1865   /// REMAINDER to the remainder, return zero.  i.e.
1866   ///
1867   ///  OLD_LHS = RHS * LHS + REMAINDER
1868   ///
1869   /// SCRATCH is a bignum of the same size as the operands and result for use by
1870   /// the routine; its contents need not be initialized and are destroyed.  LHS,
1871   /// REMAINDER and SCRATCH must be distinct.
1872   static int tcDivide(WordType *lhs, const WordType *rhs, WordType *remainder,
1873                       WordType *scratch, unsigned parts);
1874 
1875   /// Shift a bignum left Count bits. Shifted in bits are zero. There are no
1876   /// restrictions on Count.
1877   static void tcShiftLeft(WordType *, unsigned Words, unsigned Count);
1878 
1879   /// Shift a bignum right Count bits.  Shifted in bits are zero.  There are no
1880   /// restrictions on Count.
1881   static void tcShiftRight(WordType *, unsigned Words, unsigned Count);
1882 
1883   /// Comparison (unsigned) of two bignums.
1884   static int tcCompare(const WordType *, const WordType *, unsigned);
1885 
1886   /// Increment a bignum in-place.  Return the carry flag.
1887   static WordType tcIncrement(WordType *dst, unsigned parts) {
1888     return tcAddPart(dst, 1, parts);
1889   }
1890 
1891   /// Decrement a bignum in-place.  Return the borrow flag.
1892   static WordType tcDecrement(WordType *dst, unsigned parts) {
1893     return tcSubtractPart(dst, 1, parts);
1894   }
1895 
1896   /// Used to insert APInt objects, or objects that contain APInt objects, into
1897   ///  FoldingSets.
1898   void Profile(FoldingSetNodeID &id) const;
1899 
1900   /// debug method
1901   void dump() const;
1902 
1903   /// Returns whether this instance allocated memory.
1904   bool needsCleanup() const { return !isSingleWord(); }
1905 
1906 private:
1907   /// This union is used to store the integer value. When the
1908   /// integer bit-width <= 64, it uses VAL, otherwise it uses pVal.
1909   union {
1910     uint64_t VAL;   ///< Used to store the <= 64 bits integer value.
1911     uint64_t *pVal; ///< Used to store the >64 bits integer value.
1912   } U;
1913 
1914   unsigned BitWidth = 1; ///< The number of bits in this APInt.
1915 
1916   friend struct DenseMapInfo<APInt, void>;
1917   friend class APSInt;
1918 
1919   // Make DynamicAPInt a friend so it can access BitWidth directly.
1920   friend DynamicAPInt;
1921 
1922   /// This constructor is used only internally for speed of construction of
1923   /// temporaries. It is unsafe since it takes ownership of the pointer, so it
1924   /// is not public.
1925   APInt(uint64_t *val, unsigned bits) : BitWidth(bits) { U.pVal = val; }
1926 
1927   /// Determine which word a bit is in.
1928   ///
1929   /// \returns the word position for the specified bit position.
1930   static unsigned whichWord(unsigned bitPosition) {
1931     return bitPosition / APINT_BITS_PER_WORD;
1932   }
1933 
1934   /// Determine which bit in a word the specified bit position is in.
1935   static unsigned whichBit(unsigned bitPosition) {
1936     return bitPosition % APINT_BITS_PER_WORD;
1937   }
1938 
1939   /// Get a single bit mask.
1940   ///
1941   /// \returns a uint64_t with only bit at "whichBit(bitPosition)" set
1942   /// This method generates and returns a uint64_t (word) mask for a single
1943   /// bit at a specific bit position. This is used to mask the bit in the
1944   /// corresponding word.
1945   static uint64_t maskBit(unsigned bitPosition) {
1946     return 1ULL << whichBit(bitPosition);
1947   }
1948 
1949   /// Clear unused high order bits
1950   ///
1951   /// This method is used internally to clear the top "N" bits in the high order
1952   /// word that are not used by the APInt. This is needed after the most
1953   /// significant word is assigned a value to ensure that those bits are
1954   /// zero'd out.
1955   APInt &clearUnusedBits() {
1956     // Compute how many bits are used in the final word.
1957     unsigned WordBits = ((BitWidth - 1) % APINT_BITS_PER_WORD) + 1;
1958 
1959     // Mask out the high bits.
1960     uint64_t mask = WORDTYPE_MAX >> (APINT_BITS_PER_WORD - WordBits);
1961     if (LLVM_UNLIKELY(BitWidth == 0))
1962       mask = 0;
1963 
1964     if (isSingleWord())
1965       U.VAL &= mask;
1966     else
1967       U.pVal[getNumWords() - 1] &= mask;
1968     return *this;
1969   }
1970 
1971   /// Get the word corresponding to a bit position
1972   /// \returns the corresponding word for the specified bit position.
1973   uint64_t getWord(unsigned bitPosition) const {
1974     return isSingleWord() ? U.VAL : U.pVal[whichWord(bitPosition)];
1975   }
1976 
1977   /// Utility method to change the bit width of this APInt to new bit width,
1978   /// allocating and/or deallocating as necessary. There is no guarantee on the
1979   /// value of any bits upon return. Caller should populate the bits after.
1980   void reallocate(unsigned NewBitWidth);
1981 
1982   /// Convert a char array into an APInt
1983   ///
1984   /// \param radix 2, 8, 10, 16, or 36
1985   /// Converts a string into a number.  The string must be non-empty
1986   /// and well-formed as a number of the given base. The bit-width
1987   /// must be sufficient to hold the result.
1988   ///
1989   /// This is used by the constructors that take string arguments.
1990   ///
1991   /// StringRef::getAsInteger is superficially similar but (1) does
1992   /// not assume that the string is well-formed and (2) grows the
1993   /// result to hold the input.
1994   void fromString(unsigned numBits, StringRef str, uint8_t radix);
1995 
1996   /// An internal division function for dividing APInts.
1997   ///
1998   /// This is used by the toString method to divide by the radix. It simply
1999   /// provides a more convenient form of divide for internal use since KnuthDiv
2000   /// has specific constraints on its inputs. If those constraints are not met
2001   /// then it provides a simpler form of divide.
2002   static void divide(const WordType *LHS, unsigned lhsWords,
2003                      const WordType *RHS, unsigned rhsWords, WordType *Quotient,
2004                      WordType *Remainder);
2005 
2006   /// out-of-line slow case for inline constructor
2007   void initSlowCase(uint64_t val, bool isSigned);
2008 
2009   /// shared code between two array constructors
2010   void initFromArray(ArrayRef<uint64_t> array);
2011 
2012   /// out-of-line slow case for inline copy constructor
2013   void initSlowCase(const APInt &that);
2014 
2015   /// out-of-line slow case for shl
2016   void shlSlowCase(unsigned ShiftAmt);
2017 
2018   /// out-of-line slow case for lshr.
2019   void lshrSlowCase(unsigned ShiftAmt);
2020 
2021   /// out-of-line slow case for ashr.
2022   void ashrSlowCase(unsigned ShiftAmt);
2023 
2024   /// out-of-line slow case for operator=
2025   void assignSlowCase(const APInt &RHS);
2026 
2027   /// out-of-line slow case for operator==
2028   bool equalSlowCase(const APInt &RHS) const LLVM_READONLY;
2029 
2030   /// out-of-line slow case for countLeadingZeros
2031   unsigned countLeadingZerosSlowCase() const LLVM_READONLY;
2032 
2033   /// out-of-line slow case for countLeadingOnes.
2034   unsigned countLeadingOnesSlowCase() const LLVM_READONLY;
2035 
2036   /// out-of-line slow case for countTrailingZeros.
2037   unsigned countTrailingZerosSlowCase() const LLVM_READONLY;
2038 
2039   /// out-of-line slow case for countTrailingOnes
2040   unsigned countTrailingOnesSlowCase() const LLVM_READONLY;
2041 
2042   /// out-of-line slow case for countPopulation
2043   unsigned countPopulationSlowCase() const LLVM_READONLY;
2044 
2045   /// out-of-line slow case for intersects.
2046   bool intersectsSlowCase(const APInt &RHS) const LLVM_READONLY;
2047 
2048   /// out-of-line slow case for isSubsetOf.
2049   bool isSubsetOfSlowCase(const APInt &RHS) const LLVM_READONLY;
2050 
2051   /// out-of-line slow case for setBits.
2052   void setBitsSlowCase(unsigned loBit, unsigned hiBit);
2053 
2054   /// out-of-line slow case for flipAllBits.
2055   void flipAllBitsSlowCase();
2056 
2057   /// out-of-line slow case for concat.
2058   APInt concatSlowCase(const APInt &NewLSB) const;
2059 
2060   /// out-of-line slow case for operator&=.
2061   void andAssignSlowCase(const APInt &RHS);
2062 
2063   /// out-of-line slow case for operator|=.
2064   void orAssignSlowCase(const APInt &RHS);
2065 
2066   /// out-of-line slow case for operator^=.
2067   void xorAssignSlowCase(const APInt &RHS);
2068 
2069   /// Unsigned comparison. Returns -1, 0, or 1 if this APInt is less than, equal
2070   /// to, or greater than RHS.
2071   int compare(const APInt &RHS) const LLVM_READONLY;
2072 
2073   /// Signed comparison. Returns -1, 0, or 1 if this APInt is less than, equal
2074   /// to, or greater than RHS.
2075   int compareSigned(const APInt &RHS) const LLVM_READONLY;
2076 
2077   /// @}
2078 };
2079 
2080 inline bool operator==(uint64_t V1, const APInt &V2) { return V2 == V1; }
2081 
2082 inline bool operator!=(uint64_t V1, const APInt &V2) { return V2 != V1; }
2083 
2084 /// Unary bitwise complement operator.
2085 ///
2086 /// \returns an APInt that is the bitwise complement of \p v.
2087 inline APInt operator~(APInt v) {
2088   v.flipAllBits();
2089   return v;
2090 }
2091 
2092 inline APInt operator&(APInt a, const APInt &b) {
2093   a &= b;
2094   return a;
2095 }
2096 
2097 inline APInt operator&(const APInt &a, APInt &&b) {
2098   b &= a;
2099   return std::move(b);
2100 }
2101 
2102 inline APInt operator&(APInt a, uint64_t RHS) {
2103   a &= RHS;
2104   return a;
2105 }
2106 
2107 inline APInt operator&(uint64_t LHS, APInt b) {
2108   b &= LHS;
2109   return b;
2110 }
2111 
2112 inline APInt operator|(APInt a, const APInt &b) {
2113   a |= b;
2114   return a;
2115 }
2116 
2117 inline APInt operator|(const APInt &a, APInt &&b) {
2118   b |= a;
2119   return std::move(b);
2120 }
2121 
2122 inline APInt operator|(APInt a, uint64_t RHS) {
2123   a |= RHS;
2124   return a;
2125 }
2126 
2127 inline APInt operator|(uint64_t LHS, APInt b) {
2128   b |= LHS;
2129   return b;
2130 }
2131 
2132 inline APInt operator^(APInt a, const APInt &b) {
2133   a ^= b;
2134   return a;
2135 }
2136 
2137 inline APInt operator^(const APInt &a, APInt &&b) {
2138   b ^= a;
2139   return std::move(b);
2140 }
2141 
2142 inline APInt operator^(APInt a, uint64_t RHS) {
2143   a ^= RHS;
2144   return a;
2145 }
2146 
2147 inline APInt operator^(uint64_t LHS, APInt b) {
2148   b ^= LHS;
2149   return b;
2150 }
2151 
2152 inline raw_ostream &operator<<(raw_ostream &OS, const APInt &I) {
2153   I.print(OS, true);
2154   return OS;
2155 }
2156 
2157 inline APInt operator-(APInt v) {
2158   v.negate();
2159   return v;
2160 }
2161 
2162 inline APInt operator+(APInt a, const APInt &b) {
2163   a += b;
2164   return a;
2165 }
2166 
2167 inline APInt operator+(const APInt &a, APInt &&b) {
2168   b += a;
2169   return std::move(b);
2170 }
2171 
2172 inline APInt operator+(APInt a, uint64_t RHS) {
2173   a += RHS;
2174   return a;
2175 }
2176 
2177 inline APInt operator+(uint64_t LHS, APInt b) {
2178   b += LHS;
2179   return b;
2180 }
2181 
2182 inline APInt operator-(APInt a, const APInt &b) {
2183   a -= b;
2184   return a;
2185 }
2186 
2187 inline APInt operator-(const APInt &a, APInt &&b) {
2188   b.negate();
2189   b += a;
2190   return std::move(b);
2191 }
2192 
2193 inline APInt operator-(APInt a, uint64_t RHS) {
2194   a -= RHS;
2195   return a;
2196 }
2197 
2198 inline APInt operator-(uint64_t LHS, APInt b) {
2199   b.negate();
2200   b += LHS;
2201   return b;
2202 }
2203 
2204 inline APInt operator*(APInt a, uint64_t RHS) {
2205   a *= RHS;
2206   return a;
2207 }
2208 
2209 inline APInt operator*(uint64_t LHS, APInt b) {
2210   b *= LHS;
2211   return b;
2212 }
2213 
2214 namespace APIntOps {
2215 
2216 /// Determine the smaller of two APInts considered to be signed.
2217 inline const APInt &smin(const APInt &A, const APInt &B) {
2218   return A.slt(B) ? A : B;
2219 }
2220 
2221 /// Determine the larger of two APInts considered to be signed.
2222 inline const APInt &smax(const APInt &A, const APInt &B) {
2223   return A.sgt(B) ? A : B;
2224 }
2225 
2226 /// Determine the smaller of two APInts considered to be unsigned.
2227 inline const APInt &umin(const APInt &A, const APInt &B) {
2228   return A.ult(B) ? A : B;
2229 }
2230 
2231 /// Determine the larger of two APInts considered to be unsigned.
2232 inline const APInt &umax(const APInt &A, const APInt &B) {
2233   return A.ugt(B) ? A : B;
2234 }
2235 
2236 /// Determine the absolute difference of two APInts considered to be signed.
2237 inline const APInt abds(const APInt &A, const APInt &B) {
2238   return A.sge(B) ? (A - B) : (B - A);
2239 }
2240 
2241 /// Determine the absolute difference of two APInts considered to be unsigned.
2242 inline const APInt abdu(const APInt &A, const APInt &B) {
2243   return A.uge(B) ? (A - B) : (B - A);
2244 }
2245 
2246 /// Compute the floor of the signed average of C1 and C2
2247 APInt avgFloorS(const APInt &C1, const APInt &C2);
2248 
2249 /// Compute the floor of the unsigned average of C1 and C2
2250 APInt avgFloorU(const APInt &C1, const APInt &C2);
2251 
2252 /// Compute the ceil of the signed average of C1 and C2
2253 APInt avgCeilS(const APInt &C1, const APInt &C2);
2254 
2255 /// Compute the ceil of the unsigned average of C1 and C2
2256 APInt avgCeilU(const APInt &C1, const APInt &C2);
2257 
2258 /// Performs (2*N)-bit multiplication on sign-extended operands.
2259 /// Returns the high N bits of the multiplication result.
2260 APInt mulhs(const APInt &C1, const APInt &C2);
2261 
2262 /// Performs (2*N)-bit multiplication on zero-extended operands.
2263 /// Returns the high N bits of the multiplication result.
2264 APInt mulhu(const APInt &C1, const APInt &C2);
2265 
2266 /// Compute X^N for N>=0.
2267 /// 0^0 is supported and returns 1.
2268 APInt pow(const APInt &X, int64_t N);
2269 
2270 /// Compute GCD of two unsigned APInt values.
2271 ///
2272 /// This function returns the greatest common divisor of the two APInt values
2273 /// using Stein's algorithm.
2274 ///
2275 /// \returns the greatest common divisor of A and B.
2276 APInt GreatestCommonDivisor(APInt A, APInt B);
2277 
2278 /// Converts the given APInt to a double value.
2279 ///
2280 /// Treats the APInt as an unsigned value for conversion purposes.
2281 inline double RoundAPIntToDouble(const APInt &APIVal) {
2282   return APIVal.roundToDouble();
2283 }
2284 
2285 /// Converts the given APInt to a double value.
2286 ///
2287 /// Treats the APInt as a signed value for conversion purposes.
2288 inline double RoundSignedAPIntToDouble(const APInt &APIVal) {
2289   return APIVal.signedRoundToDouble();
2290 }
2291 
2292 /// Converts the given APInt to a float value.
2293 inline float RoundAPIntToFloat(const APInt &APIVal) {
2294   return float(RoundAPIntToDouble(APIVal));
2295 }
2296 
2297 /// Converts the given APInt to a float value.
2298 ///
2299 /// Treats the APInt as a signed value for conversion purposes.
2300 inline float RoundSignedAPIntToFloat(const APInt &APIVal) {
2301   return float(APIVal.signedRoundToDouble());
2302 }
2303 
2304 /// Converts the given double value into a APInt.
2305 ///
2306 /// This function convert a double value to an APInt value.
2307 APInt RoundDoubleToAPInt(double Double, unsigned width);
2308 
2309 /// Converts a float value into a APInt.
2310 ///
2311 /// Converts a float value into an APInt value.
2312 inline APInt RoundFloatToAPInt(float Float, unsigned width) {
2313   return RoundDoubleToAPInt(double(Float), width);
2314 }
2315 
2316 /// Return A unsign-divided by B, rounded by the given rounding mode.
2317 APInt RoundingUDiv(const APInt &A, const APInt &B, APInt::Rounding RM);
2318 
2319 /// Return A sign-divided by B, rounded by the given rounding mode.
2320 APInt RoundingSDiv(const APInt &A, const APInt &B, APInt::Rounding RM);
2321 
2322 /// Let q(n) = An^2 + Bn + C, and BW = bit width of the value range
2323 /// (e.g. 32 for i32).
2324 /// This function finds the smallest number n, such that
2325 /// (a) n >= 0 and q(n) = 0, or
2326 /// (b) n >= 1 and q(n-1) and q(n), when evaluated in the set of all
2327 ///     integers, belong to two different intervals [Rk, Rk+R),
2328 ///     where R = 2^BW, and k is an integer.
2329 /// The idea here is to find when q(n) "overflows" 2^BW, while at the
2330 /// same time "allowing" subtraction. In unsigned modulo arithmetic a
2331 /// subtraction (treated as addition of negated numbers) would always
2332 /// count as an overflow, but here we want to allow values to decrease
2333 /// and increase as long as they are within the same interval.
2334 /// Specifically, adding of two negative numbers should not cause an
2335 /// overflow (as long as the magnitude does not exceed the bit width).
2336 /// On the other hand, given a positive number, adding a negative
2337 /// number to it can give a negative result, which would cause the
2338 /// value to go from [-2^BW, 0) to [0, 2^BW). In that sense, zero is
2339 /// treated as a special case of an overflow.
2340 ///
2341 /// This function returns std::nullopt if after finding k that minimizes the
2342 /// positive solution to q(n) = kR, both solutions are contained between
2343 /// two consecutive integers.
2344 ///
2345 /// There are cases where q(n) > T, and q(n+1) < T (assuming evaluation
2346 /// in arithmetic modulo 2^BW, and treating the values as signed) by the
2347 /// virtue of *signed* overflow. This function will *not* find such an n,
2348 /// however it may find a value of n satisfying the inequalities due to
2349 /// an *unsigned* overflow (if the values are treated as unsigned).
2350 /// To find a solution for a signed overflow, treat it as a problem of
2351 /// finding an unsigned overflow with a range with of BW-1.
2352 ///
2353 /// The returned value may have a different bit width from the input
2354 /// coefficients.
2355 std::optional<APInt> SolveQuadraticEquationWrap(APInt A, APInt B, APInt C,
2356                                                 unsigned RangeWidth);
2357 
2358 /// Compare two values, and if they are different, return the position of the
2359 /// most significant bit that is different in the values.
2360 std::optional<unsigned> GetMostSignificantDifferentBit(const APInt &A,
2361                                                        const APInt &B);
2362 
2363 /// Splat/Merge neighboring bits to widen/narrow the bitmask represented
2364 /// by \param A to \param NewBitWidth bits.
2365 ///
2366 /// MatchAnyBits: (Default)
2367 /// e.g. ScaleBitMask(0b0101, 8) -> 0b00110011
2368 /// e.g. ScaleBitMask(0b00011011, 4) -> 0b0111
2369 ///
2370 /// MatchAllBits:
2371 /// e.g. ScaleBitMask(0b0101, 8) -> 0b00110011
2372 /// e.g. ScaleBitMask(0b00011011, 4) -> 0b0001
2373 /// A.getBitwidth() or NewBitWidth must be a whole multiples of the other.
2374 APInt ScaleBitMask(const APInt &A, unsigned NewBitWidth,
2375                    bool MatchAllBits = false);
2376 } // namespace APIntOps
2377 
2378 // See friend declaration above. This additional declaration is required in
2379 // order to compile LLVM with IBM xlC compiler.
2380 hash_code hash_value(const APInt &Arg);
2381 
2382 /// StoreIntToMemory - Fills the StoreBytes bytes of memory starting from Dst
2383 /// with the integer held in IntVal.
2384 void StoreIntToMemory(const APInt &IntVal, uint8_t *Dst, unsigned StoreBytes);
2385 
2386 /// LoadIntFromMemory - Loads the integer stored in the LoadBytes bytes starting
2387 /// from Src into IntVal, which is assumed to be wide enough and to hold zero.
2388 void LoadIntFromMemory(APInt &IntVal, const uint8_t *Src, unsigned LoadBytes);
2389 
2390 /// Provide DenseMapInfo for APInt.
2391 template <> struct DenseMapInfo<APInt, void> {
2392   static inline APInt getEmptyKey() {
2393     APInt V(nullptr, 0);
2394     V.U.VAL = ~0ULL;
2395     return V;
2396   }
2397 
2398   static inline APInt getTombstoneKey() {
2399     APInt V(nullptr, 0);
2400     V.U.VAL = ~1ULL;
2401     return V;
2402   }
2403 
2404   static unsigned getHashValue(const APInt &Key);
2405 
2406   static bool isEqual(const APInt &LHS, const APInt &RHS) {
2407     return LHS.getBitWidth() == RHS.getBitWidth() && LHS == RHS;
2408   }
2409 };
2410 
2411 } // namespace llvm
2412 
2413 #endif