llvm/Support/ScaledNumber.h

46 /// Given \c Digits and \c Scale, round up iff \c ShouldRound is \c true.
52 inline std::pair<DigitsT, int16_t> getRounded(DigitsT Digits, int16_t Scale,
57     if (!++Digits)
60   return std::make_pair(Digits, Scale);
64 inline std::pair<uint32_t, int16_t> getRounded32(uint32_t Digits, int16_t Scale,
66   return getRounded(Digits, Scale, ShouldRound);
70 inline std::pair<uint64_t, int16_t> getRounded64(uint64_t Digits, int16_t Scale,
72   return getRounded(Digits, Scale, ShouldRound);
79 inline std::pair<DigitsT, int16_t> getAdjusted(uint64_t Digits,
84   if (Width == 64 || Digits <= std::numeric_limits<DigitsT>::max())
85     return std::make_pair(Digits, Scale);
88   int Shift = 64 - Width - countLeadingZeros(Digits);
89   return getRounded<DigitsT>(Digits >> Shift, Scale + Shift,
90                              Digits & (UINT64_C(1) << (Shift - 1)));
94 inline std::pair<uint32_t, int16_t> getAdjusted32(uint64_t Digits,
96   return getAdjusted<uint32_t>(Digits, Scale);
100 inline std::pair<uint64_t, int16_t> getAdjusted64(uint64_t Digits,
102   return getAdjusted<uint64_t>(Digits, Scale);
183 /// Returns the rounded lg of \c Digits*2^Scale and an int specifying whether
186 /// Returns \c INT32_MIN when \c Digits is zero.
188 inline std::pair<int32_t, int> getLgImpl(DigitsT Digits, int16_t Scale) {
191   if (!Digits)
194   // Get the floor of the lg of Digits.
195   int32_t LocalFloor = sizeof(Digits) * 8 - countLeadingZeros(Digits) - 1;
199   if (Digits == UINT64_C(1) << LocalFloor)
204   bool Round = Digits & UINT64_C(1) << (LocalFloor - 1);
210 /// Get the lg of \c Digits*2^Scale.
212 /// Returns \c INT32_MIN when \c Digits is zero.
213 template <class DigitsT> int32_t getLg(DigitsT Digits, int16_t Scale) {
214   return getLgImpl(Digits, Scale).first;
219 /// Get the floor of the lg of \c Digits*2^Scale.
221 /// Returns \c INT32_MIN when \c Digits is zero.
222 template <class DigitsT> int32_t getLgFloor(DigitsT Digits, int16_t Scale) {
223   auto Lg = getLgImpl(Digits, Scale);
229 /// Get the ceiling of the lg of \c Digits*2^Scale.
231 /// Returns \c INT32_MIN when \c Digits is zero.
232 template <class DigitsT> int32_t getLgCeiling(DigitsT Digits, int16_t Scale) {
233   auto Lg = getLgImpl(Digits, Scale);
506   DigitsType Digits = 0;
512   constexpr ScaledNumber(DigitsType Digits, int16_t Scale)
513       : Digits(Digits), Scale(Scale) {}
517       : Digits(X.first), Scale(X.second) {}
534   DigitsType getDigits() const { return Digits; }
542   bool isZero() const { return !Digits; }
547     return Digits == DigitsType(1) << -Scale;
553   int32_t lg() const { return ScaledNumbers::getLg(Digits, Scale); }
558   int32_t lgFloor() const { return ScaledNumbers::getLgFloor(Digits, Scale); }
564     return ScaledNumbers::getLgCeiling(Digits, Scale);
596     return ScaledNumberBase::toString(Digits, Scale, Width, Precision);
604     return ScaledNumberBase::print(OS, Digits, Scale, Width, Precision);
606   void dump() const { return ScaledNumberBase::dump(Digits, Scale, Width); }
609     std::tie(Digits, Scale) =
610         ScaledNumbers::getSum(Digits, Scale, X.Digits, X.Scale);
617     std::tie(Digits, Scale) =
618         ScaledNumbers::getDifference(Digits, Scale, X.Digits, X.Scale);
644     ScaledNumbers::matchScales(Digits, Scale, X.Digits, X.Scale);
669     return ScaledNumbers::compare(Digits, Scale, X.Digits, X.Scale);
672     return ScaledNumbers::compare<uint64_t>(Digits, Scale, N, 0);
687   static int countLeadingZerosWidth(DigitsType Digits) {
689       return countLeadingZeros64(Digits);
691       return countLeadingZeros32(Digits);
692     return countLeadingZeros32(Digits) + Width - 32;
713     return ScaledNumbers::getRounded(P.Digits, P.Scale, Round);
775   return ScaledNumber<uint64_t>(Digits, Scale).scale(N);
787   IntT N = Digits;
811   *this = getProduct(Digits, X.Digits);
828   *this = getQuotient(Digits, X.Digits);
854   if (Shift > countLeadingZerosWidth(Digits)) {
860   Digits <<= Shift;
886   Digits >>= Shift;