Home | History | Annotate | Line # | Download | only in ADT 
      1 //===-- llvm/ADT/APSInt.h - Arbitrary Precision Signed Int -----*- C++ -*--===//
      2 //
      3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
      4 // See https://llvm.org/LICENSE.txt for license information.
      5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
      6 //
      7 //===----------------------------------------------------------------------===//
      8 //
      9 // This file implements the APSInt class, which is a simple class that
     10 // represents an arbitrary sized integer that knows its signedness.
     11 //
     12 //===----------------------------------------------------------------------===//
     13 
     14 #ifndef LLVM_ADT_APSINT_H
     15 #define LLVM_ADT_APSINT_H
     16 
     17 #include "llvm/ADT/APInt.h"
     18 
     19 namespace llvm {
     20 
     21 /// An arbitrary precision integer that knows its signedness.
     22 class LLVM_NODISCARD APSInt : public APInt {
     23   bool IsUnsigned;
     24 
     25 public:
     26   /// Default constructor that creates an uninitialized APInt.
     27   explicit APSInt() : IsUnsigned(false) {}
     28 
     29   /// Create an APSInt with the specified width, default to unsigned.
     30   explicit APSInt(uint32_t BitWidth, bool isUnsigned = true)
     31    : APInt(BitWidth, 0), IsUnsigned(isUnsigned) {}
     32 
     33   explicit APSInt(APInt I, bool isUnsigned = true)
     34    : APInt(std::move(I)), IsUnsigned(isUnsigned) {}
     35 
     36   /// Construct an APSInt from a string representation.
     37   ///
     38   /// This constructor interprets the string \p Str using the radix of 10.
     39   /// The interpretation stops at the end of the string. The bit width of the
     40   /// constructed APSInt is determined automatically.
     41   ///
     42   /// \param Str the string to be interpreted.
     43   explicit APSInt(StringRef Str);
     44 
     45   /// Determine sign of this APSInt.
     46   ///
     47   /// \returns true if this APSInt is negative, false otherwise
     48   bool isNegative() const { return isSigned() && APInt::isNegative(); }
     49 
     50   /// Determine if this APSInt Value is non-negative (>= 0)
     51   ///
     52   /// \returns true if this APSInt is non-negative, false otherwise
     53   bool isNonNegative() const { return !isNegative(); }
     54 
     55   /// Determine if this APSInt Value is positive.
     56   ///
     57   /// This tests if the value of this APSInt is positive (> 0). Note
     58   /// that 0 is not a positive value.
     59   ///
     60   /// \returns true if this APSInt is positive.
     61   bool isStrictlyPositive() const { return isNonNegative() && !isNullValue(); }
     62 
     63   APSInt &operator=(APInt RHS) {
     64     // Retain our current sign.
     65     APInt::operator=(std::move(RHS));
     66     return *this;
     67   }
     68 
     69   APSInt &operator=(uint64_t RHS) {
     70     // Retain our current sign.
     71     APInt::operator=(RHS);
     72     return *this;
     73   }
     74 
     75   // Query sign information.
     76   bool isSigned() const { return !IsUnsigned; }
     77   bool isUnsigned() const { return IsUnsigned; }
     78   void setIsUnsigned(bool Val) { IsUnsigned = Val; }
     79   void setIsSigned(bool Val) { IsUnsigned = !Val; }
     80 
     81   /// Append this APSInt to the specified SmallString.
     82   void toString(SmallVectorImpl<char> &Str, unsigned Radix = 10) const {
     83     APInt::toString(Str, Radix, isSigned());
     84   }
     85   /// Converts an APInt to a std::string.  This is an inefficient
     86   /// method; you should prefer passing in a SmallString instead.
     87   std::string toString(unsigned Radix) const {
     88     return APInt::toString(Radix, isSigned());
     89   }
     90   using APInt::toString;
     91 
     92   /// Get the correctly-extended \c int64_t value.
     93   int64_t getExtValue() const {
     94     assert(getMinSignedBits() <= 64 && "Too many bits for int64_t");
     95     return isSigned() ? getSExtValue() : getZExtValue();
     96   }
     97 
     98   APSInt trunc(uint32_t width) const {
     99     return APSInt(APInt::trunc(width), IsUnsigned);
    100   }
    101 
    102   APSInt extend(uint32_t width) const {
    103     if (IsUnsigned)
    104       return APSInt(zext(width), IsUnsigned);
    105     else
    106       return APSInt(sext(width), IsUnsigned);
    107   }
    108 
    109   APSInt extOrTrunc(uint32_t width) const {
    110     if (IsUnsigned)
    111       return APSInt(zextOrTrunc(width), IsUnsigned);
    112     else
    113       return APSInt(sextOrTrunc(width), IsUnsigned);
    114   }
    115 
    116   const APSInt &operator%=(const APSInt &RHS) {
    117     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    118     if (IsUnsigned)
    119       *this = urem(RHS);
    120     else
    121       *this = srem(RHS);
    122     return *this;
    123   }
    124   const APSInt &operator/=(const APSInt &RHS) {
    125     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    126     if (IsUnsigned)
    127       *this = udiv(RHS);
    128     else
    129       *this = sdiv(RHS);
    130     return *this;
    131   }
    132   APSInt operator%(const APSInt &RHS) const {
    133     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    134     return IsUnsigned ? APSInt(urem(RHS), true) : APSInt(srem(RHS), false);
    135   }
    136   APSInt operator/(const APSInt &RHS) const {
    137     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    138     return IsUnsigned ? APSInt(udiv(RHS), true) : APSInt(sdiv(RHS), false);
    139   }
    140 
    141   APSInt operator>>(unsigned Amt) const {
    142     return IsUnsigned ? APSInt(lshr(Amt), true) : APSInt(ashr(Amt), false);
    143   }
    144   APSInt& operator>>=(unsigned Amt) {
    145     if (IsUnsigned)
    146       lshrInPlace(Amt);
    147     else
    148       ashrInPlace(Amt);
    149     return *this;
    150   }
    151 
    152   inline bool operator<(const APSInt& RHS) const {
    153     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    154     return IsUnsigned ? ult(RHS) : slt(RHS);
    155   }
    156   inline bool operator>(const APSInt& RHS) const {
    157     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    158     return IsUnsigned ? ugt(RHS) : sgt(RHS);
    159   }
    160   inline bool operator<=(const APSInt& RHS) const {
    161     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    162     return IsUnsigned ? ule(RHS) : sle(RHS);
    163   }
    164   inline bool operator>=(const APSInt& RHS) const {
    165     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    166     return IsUnsigned ? uge(RHS) : sge(RHS);
    167   }
    168   inline bool operator==(const APSInt& RHS) const {
    169     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    170     return eq(RHS);
    171   }
    172   inline bool operator!=(const APSInt& RHS) const {
    173     return !((*this) == RHS);
    174   }
    175 
    176   bool operator==(int64_t RHS) const {
    177     return compareValues(*this, get(RHS)) == 0;
    178   }
    179   bool operator!=(int64_t RHS) const {
    180     return compareValues(*this, get(RHS)) != 0;
    181   }
    182   bool operator<=(int64_t RHS) const {
    183     return compareValues(*this, get(RHS)) <= 0;
    184   }
    185   bool operator>=(int64_t RHS) const {
    186     return compareValues(*this, get(RHS)) >= 0;
    187   }
    188   bool operator<(int64_t RHS) const {
    189     return compareValues(*this, get(RHS)) < 0;
    190   }
    191   bool operator>(int64_t RHS) const {
    192     return compareValues(*this, get(RHS)) > 0;
    193   }
    194 
    195   // The remaining operators just wrap the logic of APInt, but retain the
    196   // signedness information.
    197 
    198   APSInt operator<<(unsigned Bits) const {
    199     return APSInt(static_cast<const APInt&>(*this) << Bits, IsUnsigned);
    200   }
    201   APSInt& operator<<=(unsigned Amt) {
    202     static_cast<APInt&>(*this) <<= Amt;
    203     return *this;
    204   }
    205 
    206   APSInt& operator++() {
    207     ++(static_cast<APInt&>(*this));
    208     return *this;
    209   }
    210   APSInt& operator--() {
    211     --(static_cast<APInt&>(*this));
    212     return *this;
    213   }
    214   APSInt operator++(int) {
    215     return APSInt(++static_cast<APInt&>(*this), IsUnsigned);
    216   }
    217   APSInt operator--(int) {
    218     return APSInt(--static_cast<APInt&>(*this), IsUnsigned);
    219   }
    220   APSInt operator-() const {
    221     return APSInt(-static_cast<const APInt&>(*this), IsUnsigned);
    222   }
    223   APSInt& operator+=(const APSInt& RHS) {
    224     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    225     static_cast<APInt&>(*this) += RHS;
    226     return *this;
    227   }
    228   APSInt& operator-=(const APSInt& RHS) {
    229     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    230     static_cast<APInt&>(*this) -= RHS;
    231     return *this;
    232   }
    233   APSInt& operator*=(const APSInt& RHS) {
    234     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    235     static_cast<APInt&>(*this) *= RHS;
    236     return *this;
    237   }
    238   APSInt& operator&=(const APSInt& RHS) {
    239     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    240     static_cast<APInt&>(*this) &= RHS;
    241     return *this;
    242   }
    243   APSInt& operator|=(const APSInt& RHS) {
    244     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    245     static_cast<APInt&>(*this) |= RHS;
    246     return *this;
    247   }
    248   APSInt& operator^=(const APSInt& RHS) {
    249     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    250     static_cast<APInt&>(*this) ^= RHS;
    251     return *this;
    252   }
    253 
    254   APSInt operator&(const APSInt& RHS) const {
    255     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    256     return APSInt(static_cast<const APInt&>(*this) & RHS, IsUnsigned);
    257   }
    258 
    259   APSInt operator|(const APSInt& RHS) const {
    260     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    261     return APSInt(static_cast<const APInt&>(*this) | RHS, IsUnsigned);
    262   }
    263 
    264   APSInt operator^(const APSInt &RHS) const {
    265     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    266     return APSInt(static_cast<const APInt&>(*this) ^ RHS, IsUnsigned);
    267   }
    268 
    269   APSInt operator*(const APSInt& RHS) const {
    270     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    271     return APSInt(static_cast<const APInt&>(*this) * RHS, IsUnsigned);
    272   }
    273   APSInt operator+(const APSInt& RHS) const {
    274     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    275     return APSInt(static_cast<const APInt&>(*this) + RHS, IsUnsigned);
    276   }
    277   APSInt operator-(const APSInt& RHS) const {
    278     assert(IsUnsigned == RHS.IsUnsigned && "Signedness mismatch!");
    279     return APSInt(static_cast<const APInt&>(*this) - RHS, IsUnsigned);
    280   }
    281   APSInt operator~() const {
    282     return APSInt(~static_cast<const APInt&>(*this), IsUnsigned);
    283   }
    284 
    285   /// Return the APSInt representing the maximum integer value with the given
    286   /// bit width and signedness.
    287   static APSInt getMaxValue(uint32_t numBits, bool Unsigned) {
    288     return APSInt(Unsigned ? APInt::getMaxValue(numBits)
    289                            : APInt::getSignedMaxValue(numBits), Unsigned);
    290   }
    291 
    292   /// Return the APSInt representing the minimum integer value with the given
    293   /// bit width and signedness.
    294   static APSInt getMinValue(uint32_t numBits, bool Unsigned) {
    295     return APSInt(Unsigned ? APInt::getMinValue(numBits)
    296                            : APInt::getSignedMinValue(numBits), Unsigned);
    297   }
    298 
    299   /// Determine if two APSInts have the same value, zero- or
    300   /// sign-extending as needed.
    301   static bool isSameValue(const APSInt &I1, const APSInt &I2) {
    302     return !compareValues(I1, I2);
    303   }
    304 
    305   /// Compare underlying values of two numbers.
    306   static int compareValues(const APSInt &I1, const APSInt &I2) {
    307     if (I1.getBitWidth() == I2.getBitWidth() && I1.isSigned() == I2.isSigned())
    308       return I1.IsUnsigned ? I1.compare(I2) : I1.compareSigned(I2);
    309 
    310     // Check for a bit-width mismatch.
    311     if (I1.getBitWidth() > I2.getBitWidth())
    312       return compareValues(I1, I2.extend(I1.getBitWidth()));
    313     if (I2.getBitWidth() > I1.getBitWidth())
    314       return compareValues(I1.extend(I2.getBitWidth()), I2);
    315 
    316     // We have a signedness mismatch. Check for negative values and do an
    317     // unsigned compare if both are positive.
    318     if (I1.isSigned()) {
    319       assert(!I2.isSigned() && "Expected signed mismatch");
    320       if (I1.isNegative())
    321         return -1;
    322     } else {
    323       assert(I2.isSigned() && "Expected signed mismatch");
    324       if (I2.isNegative())
    325         return 1;
    326     }
    327 
    328     return I1.compare(I2);
    329   }
    330 
    331   static APSInt get(int64_t X) { return APSInt(APInt(64, X), false); }
    332   static APSInt getUnsigned(uint64_t X) { return APSInt(APInt(64, X), true); }
    333 
    334   /// Used to insert APSInt objects, or objects that contain APSInt objects,
    335   /// into FoldingSets.
    336   void Profile(FoldingSetNodeID& ID) const;
    337 };
    338 
    339 inline bool operator==(int64_t V1, const APSInt &V2) { return V2 == V1; }
    340 inline bool operator!=(int64_t V1, const APSInt &V2) { return V2 != V1; }
    341 inline bool operator<=(int64_t V1, const APSInt &V2) { return V2 >= V1; }
    342 inline bool operator>=(int64_t V1, const APSInt &V2) { return V2 <= V1; }
    343 inline bool operator<(int64_t V1, const APSInt &V2) { return V2 > V1; }
    344 inline bool operator>(int64_t V1, const APSInt &V2) { return V2 < V1; }
    345 
    346 inline raw_ostream &operator<<(raw_ostream &OS, const APSInt &I) {
    347   I.print(OS, I.isSigned());
    348   return OS;
    349 }
    350 
    351 } // end namespace llvm
    352 
    353 #endif
    354