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//===-- llvm/ADT/APInt.h - For Arbitrary Precision Integer -----*- C++ -*--===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// \file
/// \brief This file implements a class to represent arbitrary precision
/// integral constant values and operations on them.
///
//===----------------------------------------------------------------------===//
#ifndef LLVM_ADT_APINT_H
#define LLVM_ADT_APINT_H
#include "llvm/Support/Compiler.h"
#include "llvm/Support/MathExtras.h"
#include <cassert>
#include <climits>
#include <cstring>
#include <string>
namespace llvm {
class FoldingSetNodeID;
class StringRef;
class hash_code;
class raw_ostream;
template <typename T> class SmallVectorImpl;
template <typename T> class ArrayRef;
// An unsigned host type used as a single part of a multi-part
// bignum.
typedef uint64_t integerPart;
const unsigned int host_char_bit = 8;
const unsigned int integerPartWidth =
host_char_bit * static_cast<unsigned int>(sizeof(integerPart));
class APInt;
inline APInt operator-(APInt);
//===----------------------------------------------------------------------===//
// APInt Class
//===----------------------------------------------------------------------===//
/// \brief Class for arbitrary precision integers.
///
/// APInt is a functional replacement for common case unsigned integer type like
/// "unsigned", "unsigned long" or "uint64_t", but also allows non-byte-width
/// integer sizes and large integer value types such as 3-bits, 15-bits, or more
/// than 64-bits of precision. APInt provides a variety of arithmetic operators
/// and methods to manipulate integer values of any bit-width. It supports both
/// the typical integer arithmetic and comparison operations as well as bitwise
/// manipulation.
///
/// The class has several invariants worth noting:
/// * All bit, byte, and word positions are zero-based.
/// * Once the bit width is set, it doesn't change except by the Truncate,
/// SignExtend, or ZeroExtend operations.
/// * All binary operators must be on APInt instances of the same bit width.
/// Attempting to use these operators on instances with different bit
/// widths will yield an assertion.
/// * The value is stored canonically as an unsigned value. For operations
/// where it makes a difference, there are both signed and unsigned variants
/// of the operation. For example, sdiv and udiv. However, because the bit
/// widths must be the same, operations such as Mul and Add produce the same
/// results regardless of whether the values are interpreted as signed or
/// not.
/// * In general, the class tries to follow the style of computation that LLVM
/// uses in its IR. This simplifies its use for LLVM.
///
class LLVM_NODISCARD APInt {
unsigned BitWidth; ///< The number of bits in this APInt.
/// This union is used to store the integer value. When the
/// integer bit-width <= 64, it uses VAL, otherwise it uses pVal.
union {
uint64_t VAL; ///< Used to store the <= 64 bits integer value.
uint64_t *pVal; ///< Used to store the >64 bits integer value.
};
/// This enum is used to hold the constants we needed for APInt.
enum {
/// Bits in a word
APINT_BITS_PER_WORD =
static_cast<unsigned int>(sizeof(uint64_t)) * CHAR_BIT,
/// Byte size of a word
APINT_WORD_SIZE = static_cast<unsigned int>(sizeof(uint64_t))
};
friend struct DenseMapAPIntKeyInfo;
/// \brief Fast internal constructor
///
/// This constructor is used only internally for speed of construction of
/// temporaries. It is unsafe for general use so it is not public.
APInt(uint64_t *val, unsigned bits) : BitWidth(bits), pVal(val) {}
/// \brief Determine if this APInt just has one word to store value.
///
/// \returns true if the number of bits <= 64, false otherwise.
bool isSingleWord() const { return BitWidth <= APINT_BITS_PER_WORD; }
/// \brief Determine which word a bit is in.
///
/// \returns the word position for the specified bit position.
static unsigned whichWord(unsigned bitPosition) {
return bitPosition / APINT_BITS_PER_WORD;
}
/// \brief Determine which bit in a word a bit is in.
///
/// \returns the bit position in a word for the specified bit position
/// in the APInt.
static unsigned whichBit(unsigned bitPosition) {
return bitPosition % APINT_BITS_PER_WORD;
}
/// \brief Get a single bit mask.
///
/// \returns a uint64_t with only bit at "whichBit(bitPosition)" set
/// This method generates and returns a uint64_t (word) mask for a single
/// bit at a specific bit position. This is used to mask the bit in the
/// corresponding word.
static uint64_t maskBit(unsigned bitPosition) {
return 1ULL << whichBit(bitPosition);
}
/// \brief Clear unused high order bits
///
/// This method is used internally to clear the top "N" bits in the high order
/// word that are not used by the APInt. This is needed after the most
/// significant word is assigned a value to ensure that those bits are
/// zero'd out.
APInt &clearUnusedBits() {
// Compute how many bits are used in the final word
unsigned wordBits = BitWidth % APINT_BITS_PER_WORD;
if (wordBits == 0)
// If all bits are used, we want to leave the value alone. This also
// avoids the undefined behavior of >> when the shift is the same size as
// the word size (64).
return *this;
// Mask out the high bits.
uint64_t mask = ~uint64_t(0ULL) >> (APINT_BITS_PER_WORD - wordBits);
if (isSingleWord())
VAL &= mask;
else
pVal[getNumWords() - 1] &= mask;
return *this;
}
/// \brief Get the word corresponding to a bit position
/// \returns the corresponding word for the specified bit position.
uint64_t getWord(unsigned bitPosition) const {
return isSingleWord() ? VAL : pVal[whichWord(bitPosition)];
}
/// \brief Convert a char array into an APInt
///
/// \param radix 2, 8, 10, 16, or 36
/// Converts a string into a number. The string must be non-empty
/// and well-formed as a number of the given base. The bit-width
/// must be sufficient to hold the result.
///
/// This is used by the constructors that take string arguments.
///
/// StringRef::getAsInteger is superficially similar but (1) does
/// not assume that the string is well-formed and (2) grows the
/// result to hold the input.
void fromString(unsigned numBits, StringRef str, uint8_t radix);
/// \brief An internal division function for dividing APInts.
///
/// This is used by the toString method to divide by the radix. It simply
/// provides a more convenient form of divide for internal use since KnuthDiv
/// has specific constraints on its inputs. If those constraints are not met
/// then it provides a simpler form of divide.
static void divide(const APInt &LHS, unsigned lhsWords, const APInt &RHS,
unsigned rhsWords, APInt *Quotient, APInt *Remainder);
/// out-of-line slow case for inline constructor
void initSlowCase(uint64_t val, bool isSigned);
/// shared code between two array constructors
void initFromArray(ArrayRef<uint64_t> array);
/// out-of-line slow case for inline copy constructor
void initSlowCase(const APInt &that);
/// out-of-line slow case for shl
APInt shlSlowCase(unsigned shiftAmt) const;
/// out-of-line slow case for operator&
APInt AndSlowCase(const APInt &RHS) const;
/// out-of-line slow case for operator|
APInt OrSlowCase(const APInt &RHS) const;
/// out-of-line slow case for operator^
APInt XorSlowCase(const APInt &RHS) const;
/// out-of-line slow case for operator=
APInt &AssignSlowCase(const APInt &RHS);
/// out-of-line slow case for operator==
bool EqualSlowCase(const APInt &RHS) const;
/// out-of-line slow case for operator==
bool EqualSlowCase(uint64_t Val) const;
/// out-of-line slow case for countLeadingZeros
unsigned countLeadingZerosSlowCase() const;
/// out-of-line slow case for countTrailingOnes
unsigned countTrailingOnesSlowCase() const;
/// out-of-line slow case for countPopulation
unsigned countPopulationSlowCase() const;
public:
/// \name Constructors
/// @{
/// \brief Create a new APInt of numBits width, initialized as val.
///
/// If isSigned is true then val is treated as if it were a signed value
/// (i.e. as an int64_t) and the appropriate sign extension to the bit width
/// will be done. Otherwise, no sign extension occurs (high order bits beyond
/// the range of val are zero filled).
///
/// \param numBits the bit width of the constructed APInt
/// \param val the initial value of the APInt
/// \param isSigned how to treat signedness of val
APInt(unsigned numBits, uint64_t val, bool isSigned = false)
: BitWidth(numBits), VAL(0) {
assert(BitWidth && "bitwidth too small");
if (isSingleWord())
VAL = val;
else
initSlowCase(val, isSigned);
clearUnusedBits();
}
/// \brief Construct an APInt of numBits width, initialized as bigVal[].
///
/// Note that bigVal.size() can be smaller or larger than the corresponding
/// bit width but any extraneous bits will be dropped.
///
/// \param numBits the bit width of the constructed APInt
/// \param bigVal a sequence of words to form the initial value of the APInt
APInt(unsigned numBits, ArrayRef<uint64_t> bigVal);
/// Equivalent to APInt(numBits, ArrayRef<uint64_t>(bigVal, numWords)), but
/// deprecated because this constructor is prone to ambiguity with the
/// APInt(unsigned, uint64_t, bool) constructor.
///
/// If this overload is ever deleted, care should be taken to prevent calls
/// from being incorrectly captured by the APInt(unsigned, uint64_t, bool)
/// constructor.
APInt(unsigned numBits, unsigned numWords, const uint64_t bigVal[]);
/// \brief Construct an APInt from a string representation.
///
/// This constructor interprets the string \p str in the given radix. The
/// interpretation stops when the first character that is not suitable for the
/// radix is encountered, or the end of the string. Acceptable radix values
/// are 2, 8, 10, 16, and 36. It is an error for the value implied by the
/// string to require more bits than numBits.
///
/// \param numBits the bit width of the constructed APInt
/// \param str the string to be interpreted
/// \param radix the radix to use for the conversion
APInt(unsigned numBits, StringRef str, uint8_t radix);
/// Simply makes *this a copy of that.
/// @brief Copy Constructor.
APInt(const APInt &that) : BitWidth(that.BitWidth), VAL(0) {
if (isSingleWord())
VAL = that.VAL;
else
initSlowCase(that);
}
/// \brief Move Constructor.
APInt(APInt &&that) : BitWidth(that.BitWidth), VAL(that.VAL) {
that.BitWidth = 0;
}
/// \brief Destructor.
~APInt() {
if (needsCleanup())
delete[] pVal;
}
/// \brief Default constructor that creates an uninteresting APInt
/// representing a 1-bit zero value.
///
/// This is useful for object deserialization (pair this with the static
/// method Read).
explicit APInt() : BitWidth(1), VAL(0) {}
/// \brief Returns whether this instance allocated memory.
bool needsCleanup() const { return !isSingleWord(); }
/// Used to insert APInt objects, or objects that contain APInt objects, into
/// FoldingSets.
void Profile(FoldingSetNodeID &id) const;
/// @}
/// \name Value Tests
/// @{
/// \brief Determine sign of this APInt.
///
/// This tests the high bit of this APInt to determine if it is set.
///
/// \returns true if this APInt is negative, false otherwise
bool isNegative() const { return (*this)[BitWidth - 1]; }
/// \brief Determine if this APInt Value is non-negative (>= 0)
///
/// This tests the high bit of the APInt to determine if it is unset.
bool isNonNegative() const { return !isNegative(); }
/// \brief Determine if this APInt Value is positive.
///
/// This tests if the value of this APInt is positive (> 0). Note
/// that 0 is not a positive value.
///
/// \returns true if this APInt is positive.
bool isStrictlyPositive() const { return isNonNegative() && !!*this; }
/// \brief Determine if all bits are set
///
/// This checks to see if the value has all bits of the APInt are set or not.
bool isAllOnesValue() const {
if (isSingleWord())
return VAL == ~integerPart(0) >> (APINT_BITS_PER_WORD - BitWidth);
return countPopulationSlowCase() == BitWidth;
}
/// \brief Determine if this is the largest unsigned value.
///
/// This checks to see if the value of this APInt is the maximum unsigned
/// value for the APInt's bit width.
bool isMaxValue() const { return isAllOnesValue(); }
/// \brief Determine if this is the largest signed value.
///
/// This checks to see if the value of this APInt is the maximum signed
/// value for the APInt's bit width.
bool isMaxSignedValue() const {
return !isNegative() && countPopulation() == BitWidth - 1;
}
/// \brief Determine if this is the smallest unsigned value.
///
/// This checks to see if the value of this APInt is the minimum unsigned
/// value for the APInt's bit width.
bool isMinValue() const { return !*this; }
/// \brief Determine if this is the smallest signed value.
///
/// This checks to see if the value of this APInt is the minimum signed
/// value for the APInt's bit width.
bool isMinSignedValue() const {
return isNegative() && isPowerOf2();
}
/// \brief Check if this APInt has an N-bits unsigned integer value.
bool isIntN(unsigned N) const {
assert(N && "N == 0 ???");
return getActiveBits() <= N;
}
/// \brief Check if this APInt has an N-bits signed integer value.
bool isSignedIntN(unsigned N) const {
assert(N && "N == 0 ???");
return getMinSignedBits() <= N;
}
/// \brief Check if this APInt's value is a power of two greater than zero.
///
/// \returns true if the argument APInt value is a power of two > 0.
bool isPowerOf2() const {
if (isSingleWord())
return isPowerOf2_64(VAL);
return countPopulationSlowCase() == 1;
}
/// \brief Check if the APInt's value is returned by getSignBit.
///
/// \returns true if this is the value returned by getSignBit.
bool isSignBit() const { return isMinSignedValue(); }
/// \brief Convert APInt to a boolean value.
///
/// This converts the APInt to a boolean value as a test against zero.
bool getBoolValue() const { return !!*this; }
/// If this value is smaller than the specified limit, return it, otherwise
/// return the limit value. This causes the value to saturate to the limit.
uint64_t getLimitedValue(uint64_t Limit = ~0ULL) const {
return (getActiveBits() > 64 || getZExtValue() > Limit) ? Limit
: getZExtValue();
}
/// \brief Check if the APInt consists of a repeated bit pattern.
///
/// e.g. 0x01010101 satisfies isSplat(8).
/// \param SplatSizeInBits The size of the pattern in bits. Must divide bit
/// width without remainder.
bool isSplat(unsigned SplatSizeInBits) const;
/// @}
/// \name Value Generators
/// @{
/// \brief Gets maximum unsigned value of APInt for specific bit width.
static APInt getMaxValue(unsigned numBits) {
return getAllOnesValue(numBits);
}
/// \brief Gets maximum signed value of APInt for a specific bit width.
static APInt getSignedMaxValue(unsigned numBits) {
APInt API = getAllOnesValue(numBits);
API.clearBit(numBits - 1);
return API;
}
/// \brief Gets minimum unsigned value of APInt for a specific bit width.
static APInt getMinValue(unsigned numBits) { return APInt(numBits, 0); }
/// \brief Gets minimum signed value of APInt for a specific bit width.
static APInt getSignedMinValue(unsigned numBits) {
APInt API(numBits, 0);
API.setBit(numBits - 1);
return API;
}
/// \brief Get the SignBit for a specific bit width.
///
/// This is just a wrapper function of getSignedMinValue(), and it helps code
/// readability when we want to get a SignBit.
static APInt getSignBit(unsigned BitWidth) {
return getSignedMinValue(BitWidth);
}
/// \brief Get the all-ones value.
///
/// \returns the all-ones value for an APInt of the specified bit-width.
static APInt getAllOnesValue(unsigned numBits) {
return APInt(numBits, UINT64_MAX, true);
}
/// \brief Get the '0' value.
///
/// \returns the '0' value for an APInt of the specified bit-width.
static APInt getNullValue(unsigned numBits) { return APInt(numBits, 0); }
/// \brief Compute an APInt containing numBits highbits from this APInt.
///
/// Get an APInt with the same BitWidth as this APInt, just zero mask
/// the low bits and right shift to the least significant bit.
///
/// \returns the high "numBits" bits of this APInt.
APInt getHiBits(unsigned numBits) const;
/// \brief Compute an APInt containing numBits lowbits from this APInt.
///
/// Get an APInt with the same BitWidth as this APInt, just zero mask
/// the high bits.
///
/// \returns the low "numBits" bits of this APInt.
APInt getLoBits(unsigned numBits) const;
/// \brief Return an APInt with exactly one bit set in the result.
static APInt getOneBitSet(unsigned numBits, unsigned BitNo) {
APInt Res(numBits, 0);
Res.setBit(BitNo);
return Res;
}
/// \brief Get a value with a block of bits set.
///
/// Constructs an APInt value that has a contiguous range of bits set. The
/// bits from loBit (inclusive) to hiBit (exclusive) will be set. All other
/// bits will be zero. For example, with parameters(32, 0, 16) you would get
/// 0x0000FFFF. If hiBit is less than loBit then the set bits "wrap". For
/// example, with parameters (32, 28, 4), you would get 0xF000000F.
///
/// \param numBits the intended bit width of the result
/// \param loBit the index of the lowest bit set.
/// \param hiBit the index of the highest bit set.
///
/// \returns An APInt value with the requested bits set.
static APInt getBitsSet(unsigned numBits, unsigned loBit, unsigned hiBit) {
assert(hiBit <= numBits && "hiBit out of range");
assert(loBit < numBits && "loBit out of range");
if (hiBit < loBit)
return getLowBitsSet(numBits, hiBit) |
getHighBitsSet(numBits, numBits - loBit);
return getLowBitsSet(numBits, hiBit - loBit).shl(loBit);
}
/// \brief Get a value with high bits set
///
/// Constructs an APInt value that has the top hiBitsSet bits set.
///
/// \param numBits the bitwidth of the result
/// \param hiBitsSet the number of high-order bits set in the result.
static APInt getHighBitsSet(unsigned numBits, unsigned hiBitsSet) {
assert(hiBitsSet <= numBits && "Too many bits to set!");
// Handle a degenerate case, to avoid shifting by word size
if (hiBitsSet == 0)
return APInt(numBits, 0);
unsigned shiftAmt = numBits - hiBitsSet;
// For small values, return quickly
if (numBits <= APINT_BITS_PER_WORD)
return APInt(numBits, ~0ULL << shiftAmt);
return getAllOnesValue(numBits).shl(shiftAmt);
}
/// \brief Get a value with low bits set
///
/// Constructs an APInt value that has the bottom loBitsSet bits set.
///
/// \param numBits the bitwidth of the result
/// \param loBitsSet the number of low-order bits set in the result.
static APInt getLowBitsSet(unsigned numBits, unsigned loBitsSet) {
assert(loBitsSet <= numBits && "Too many bits to set!");
// Handle a degenerate case, to avoid shifting by word size
if (loBitsSet == 0)
return APInt(numBits, 0);
if (loBitsSet == APINT_BITS_PER_WORD)
return APInt(numBits, UINT64_MAX);
// For small values, return quickly.
if (loBitsSet <= APINT_BITS_PER_WORD)
return APInt(numBits, UINT64_MAX >> (APINT_BITS_PER_WORD - loBitsSet));
return getAllOnesValue(numBits).lshr(numBits - loBitsSet);
}
/// \brief Return a value containing V broadcasted over NewLen bits.
static APInt getSplat(unsigned NewLen, const APInt &V) {
assert(NewLen >= V.getBitWidth() && "Can't splat to smaller bit width!");
APInt Val = V.zextOrSelf(NewLen);
for (unsigned I = V.getBitWidth(); I < NewLen; I <<= 1)
Val |= Val << I;
return Val;
}
/// \brief Determine if two APInts have the same value, after zero-extending
/// one of them (if needed!) to ensure that the bit-widths match.
static bool isSameValue(const APInt &I1, const APInt &I2) {
if (I1.getBitWidth() == I2.getBitWidth())
return I1 == I2;
if (I1.getBitWidth() > I2.getBitWidth())
return I1 == I2.zext(I1.getBitWidth());
return I1.zext(I2.getBitWidth()) == I2;
}
/// \brief Overload to compute a hash_code for an APInt value.
friend hash_code hash_value(const APInt &Arg);
/// This function returns a pointer to the internal storage of the APInt.
/// This is useful for writing out the APInt in binary form without any
/// conversions.
const uint64_t *getRawData() const {
if (isSingleWord())
return &VAL;
return &pVal[0];
}
/// @}
/// \name Unary Operators
/// @{
/// \brief Postfix increment operator.
///
/// \returns a new APInt value representing *this incremented by one
const APInt operator++(int) {
APInt API(*this);
++(*this);
return API;
}
/// \brief Prefix increment operator.
///
/// \returns *this incremented by one
APInt &operator++();
/// \brief Postfix decrement operator.
///
/// \returns a new APInt representing *this decremented by one.
const APInt operator--(int) {
APInt API(*this);
--(*this);
return API;
}
/// \brief Prefix decrement operator.
///
/// \returns *this decremented by one.
APInt &operator--();
/// \brief Unary bitwise complement operator.
///
/// Performs a bitwise complement operation on this APInt.
///
/// \returns an APInt that is the bitwise complement of *this
APInt operator~() const {
APInt Result(*this);
Result.flipAllBits();
return Result;
}
/// \brief Logical negation operator.
///
/// Performs logical negation operation on this APInt.
///
/// \returns true if *this is zero, false otherwise.
bool operator!() const {
if (isSingleWord())
return !VAL;
for (unsigned i = 0; i != getNumWords(); ++i)
if (pVal[i])
return false;
return true;
}
/// @}
/// \name Assignment Operators
/// @{
/// \brief Copy assignment operator.
///
/// \returns *this after assignment of RHS.
APInt &operator=(const APInt &RHS) {
// If the bitwidths are the same, we can avoid mucking with memory
if (isSingleWord() && RHS.isSingleWord()) {
VAL = RHS.VAL;
BitWidth = RHS.BitWidth;
return clearUnusedBits();
}
return AssignSlowCase(RHS);
}
/// @brief Move assignment operator.
APInt &operator=(APInt &&that) {
if (!isSingleWord()) {
// The MSVC STL shipped in 2013 requires that self move assignment be a
// no-op. Otherwise algorithms like stable_sort will produce answers
// where half of the output is left in a moved-from state.
if (this == &that)
return *this;
delete[] pVal;
}
// Use memcpy so that type based alias analysis sees both VAL and pVal
// as modified.
memcpy(&VAL, &that.VAL, sizeof(uint64_t));
// If 'this == &that', avoid zeroing our own bitwidth by storing to 'that'
// first.
unsigned ThatBitWidth = that.BitWidth;
that.BitWidth = 0;
BitWidth = ThatBitWidth;
return *this;
}
/// \brief Assignment operator.
///
/// The RHS value is assigned to *this. If the significant bits in RHS exceed
/// the bit width, the excess bits are truncated. If the bit width is larger
/// than 64, the value is zero filled in the unspecified high order bits.
///
/// \returns *this after assignment of RHS value.
APInt &operator=(uint64_t RHS);
/// \brief Bitwise AND assignment operator.
///
/// Performs a bitwise AND operation on this APInt and RHS. The result is
/// assigned to *this.
///
/// \returns *this after ANDing with RHS.
APInt &operator&=(const APInt &RHS);
/// \brief Bitwise OR assignment operator.
///
/// Performs a bitwise OR operation on this APInt and RHS. The result is
/// assigned *this;
///
/// \returns *this after ORing with RHS.
APInt &operator|=(const APInt &RHS);
/// \brief Bitwise OR assignment operator.
///
/// Performs a bitwise OR operation on this APInt and RHS. RHS is
/// logically zero-extended or truncated to match the bit-width of
/// the LHS.
APInt &operator|=(uint64_t RHS) {
if (isSingleWord()) {
VAL |= RHS;
clearUnusedBits();
} else {
pVal[0] |= RHS;
}
return *this;
}
/// \brief Bitwise XOR assignment operator.
///
/// Performs a bitwise XOR operation on this APInt and RHS. The result is
/// assigned to *this.
///
/// \returns *this after XORing with RHS.
APInt &operator^=(const APInt &RHS);
/// \brief Multiplication assignment operator.
///
/// Multiplies this APInt by RHS and assigns the result to *this.
///
/// \returns *this
APInt &operator*=(const APInt &RHS);
/// \brief Addition assignment operator.
///
/// Adds RHS to *this and assigns the result to *this.
///
/// \returns *this
APInt &operator+=(const APInt &RHS);
APInt &operator+=(uint64_t RHS);
/// \brief Subtraction assignment operator.
///
/// Subtracts RHS from *this and assigns the result to *this.
///
/// \returns *this
APInt &operator-=(const APInt &RHS);
APInt &operator-=(uint64_t RHS);
/// \brief Left-shift assignment function.
///
/// Shifts *this left by shiftAmt and assigns the result to *this.
///
/// \returns *this after shifting left by shiftAmt
APInt &operator<<=(unsigned shiftAmt) {
*this = shl(shiftAmt);
return *this;
}
/// @}
/// \name Binary Operators
/// @{
/// \brief Bitwise AND operator.
///
/// Performs a bitwise AND operation on *this and RHS.
///
/// \returns An APInt value representing the bitwise AND of *this and RHS.
APInt operator&(const APInt &RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
if (isSingleWord())
return APInt(getBitWidth(), VAL & RHS.VAL);
return AndSlowCase(RHS);
}
APInt And(const APInt &RHS) const { return this->operator&(RHS); }
/// \brief Bitwise OR operator.
///
/// Performs a bitwise OR operation on *this and RHS.
///
/// \returns An APInt value representing the bitwise OR of *this and RHS.
APInt operator|(const APInt &RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
if (isSingleWord())
return APInt(getBitWidth(), VAL | RHS.VAL);
return OrSlowCase(RHS);
}
/// \brief Bitwise OR function.
///
/// Performs a bitwise or on *this and RHS. This is implemented by simply
/// calling operator|.
///
/// \returns An APInt value representing the bitwise OR of *this and RHS.
APInt Or(const APInt &RHS) const { return this->operator|(RHS); }
/// \brief Bitwise XOR operator.
///
/// Performs a bitwise XOR operation on *this and RHS.
///
/// \returns An APInt value representing the bitwise XOR of *this and RHS.
APInt operator^(const APInt &RHS) const {
assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
if (isSingleWord())
return APInt(BitWidth, VAL ^ RHS.VAL);
return XorSlowCase(RHS);
}
/// \brief Bitwise XOR function.
///
/// Performs a bitwise XOR operation on *this and RHS. This is implemented
/// through the usage of operator^.
///
/// \returns An APInt value representing the bitwise XOR of *this and RHS.
APInt Xor(const APInt &RHS) const { return this->operator^(RHS); }
/// \brief Multiplication operator.
///
/// Multiplies this APInt by RHS and returns the result.
APInt operator*(const APInt &RHS) const;
/// \brief Left logical shift operator.
///
/// Shifts this APInt left by \p Bits and returns the result.
APInt operator<<(unsigned Bits) const { return shl(Bits); }
/// \brief Left logical shift operator.
///
/// Shifts this APInt left by \p Bits and returns the result.
APInt operator<<(const APInt &Bits) const { return shl(Bits); }
/// \brief Arithmetic right-shift function.
///
/// Arithmetic right-shift this APInt by shiftAmt.
APInt ashr(unsigned shiftAmt) const;
/// \brief Logical right-shift function.
///
/// Logical right-shift this APInt by shiftAmt.
APInt lshr(unsigned shiftAmt) const;
/// \brief Left-shift function.
///
/// Left-shift this APInt by shiftAmt.
APInt shl(unsigned shiftAmt) const {
assert(shiftAmt <= BitWidth && "Invalid shift amount");
if (isSingleWord()) {
if (shiftAmt >= BitWidth)
return APInt(BitWidth, 0); // avoid undefined shift results
return APInt(BitWidth, VAL << shiftAmt);
}
return shlSlowCase(shiftAmt);
}
/// \brief Rotate left by rotateAmt.
APInt rotl(unsigned rotateAmt) const;
/// \brief Rotate right by rotateAmt.
APInt rotr(unsigned rotateAmt) const;
/// \brief Arithmetic right-shift function.
///
/// Arithmetic right-shift this APInt by shiftAmt.
APInt ashr(const APInt &shiftAmt) const;
/// \brief Logical right-shift function.
///
/// Logical right-shift this APInt by shiftAmt.
APInt lshr(const APInt &shiftAmt) const;
/// \brief Left-shift function.
///
/// Left-shift this APInt by shiftAmt.
APInt shl(const APInt &shiftAmt) const;
/// \brief Rotate left by rotateAmt.
APInt rotl(const APInt &rotateAmt) const;
/// \brief Rotate right by rotateAmt.
APInt rotr(const APInt &rotateAmt) const;
/// \brief Unsigned division operation.
///
/// Perform an unsigned divide operation on this APInt by RHS. Both this and
/// RHS are treated as unsigned quantities for purposes of this division.
///
/// \returns a new APInt value containing the division result
APInt udiv(const APInt &RHS) const;
/// \brief Signed division function for APInt.
///
/// Signed divide this APInt by APInt RHS.
APInt sdiv(const APInt &RHS) const;
/// \brief Unsigned remainder operation.
///
/// Perform an unsigned remainder operation on this APInt with RHS being the
/// divisor. Both this and RHS are treated as unsigned quantities for purposes
/// of this operation. Note that this is a true remainder operation and not a
/// modulo operation because the sign follows the sign of the dividend which
/// is *this.
///
/// \returns a new APInt value containing the remainder result
APInt urem(const APInt &RHS) const;
/// \brief Function for signed remainder operation.
///
/// Signed remainder operation on APInt.
APInt srem(const APInt &RHS) const;
/// \brief Dual division/remainder interface.
///
/// Sometimes it is convenient to divide two APInt values and obtain both the
/// quotient and remainder. This function does both operations in the same
/// computation making it a little more efficient. The pair of input arguments
/// may overlap with the pair of output arguments. It is safe to call
/// udivrem(X, Y, X, Y), for example.
static void udivrem(const APInt &LHS, const APInt &RHS, APInt &Quotient,
APInt &Remainder);
static void sdivrem(const APInt &LHS, const APInt &RHS, APInt &Quotient,
APInt &Remainder);
// Operations that return overflow indicators.
APInt sadd_ov(const APInt &RHS, bool &Overflow) const;
APInt uadd_ov(const APInt &RHS, bool &Overflow) const;
APInt ssub_ov(const APInt &RHS, bool &Overflow) const;
APInt usub_ov(const APInt &RHS, bool &Overflow) const;
APInt sdiv_ov(const APInt &RHS, bool &Overflow) const;
APInt smul_ov(const APInt &RHS, bool &Overflow) const;
APInt umul_ov(const APInt &RHS, bool &Overflow) const;
APInt sshl_ov(const APInt &Amt, bool &Overflow) const;
APInt ushl_ov(const APInt &Amt, bool &Overflow) const;
/// \brief Array-indexing support.
///
/// \returns the bit value at bitPosition
bool operator[](unsigned bitPosition) const {
assert(bitPosition < getBitWidth() && "Bit position out of bounds!");
return (maskBit(bitPosition) &
(isSingleWord() ? VAL : pVal[whichWord(bitPosition)])) !=
0;
}
/// @}
/// \name Comparison Operators
/// @{
/// \brief Equality operator.
///
/// Compares this APInt with RHS for the validity of the equality
/// relationship.
bool operator==(const APInt &RHS) const {
assert(BitWidth == RHS.BitWidth && "Comparison requires equal bit widths");
if (isSingleWord())
return VAL == RHS.VAL;
return EqualSlowCase(RHS);
}
/// \brief Equality operator.
///
/// Compares this APInt with a uint64_t for the validity of the equality
/// relationship.
///
/// \returns true if *this == Val
bool operator==(uint64_t Val) const {
if (isSingleWord())
return VAL == Val;
return EqualSlowCase(Val);
}
/// \brief Equality comparison.
///
/// Compares this APInt with RHS for the validity of the equality
/// relationship.
///
/// \returns true if *this == Val
bool eq(const APInt &RHS) const { return (*this) == RHS; }
/// \brief Inequality operator.
///
/// Compares this APInt with RHS for the validity of the inequality
/// relationship.
///
/// \returns true if *this != Val
bool operator!=(const APInt &RHS) const { return !((*this) == RHS); }
/// \brief Inequality operator.
///
/// Compares this APInt with a uint64_t for the validity of the inequality
/// relationship.
///
/// \returns true if *this != Val
bool operator!=(uint64_t Val) const { return !((*this) == Val); }
/// \brief Inequality comparison
///
/// Compares this APInt with RHS for the validity of the inequality
/// relationship.
///
/// \returns true if *this != Val
bool ne(const APInt &RHS) const { return !((*this) == RHS); }
/// \brief Unsigned less than comparison
///
/// Regards both *this and RHS as unsigned quantities and compares them for
/// the validity of the less-than relationship.
///
/// \returns true if *this < RHS when both are considered unsigned.
bool ult(const APInt &RHS) const;
/// \brief Unsigned less than comparison
///
/// Regards both *this as an unsigned quantity and compares it with RHS for
/// the validity of the less-than relationship.
///
/// \returns true if *this < RHS when considered unsigned.
bool ult(uint64_t RHS) const {
return getActiveBits() > 64 ? false : getZExtValue() < RHS;
}
/// \brief Signed less than comparison
///
/// Regards both *this and RHS as signed quantities and compares them for
/// validity of the less-than relationship.
///
/// \returns true if *this < RHS when both are considered signed.
bool slt(const APInt &RHS) const;
/// \brief Signed less than comparison
///
/// Regards both *this as a signed quantity and compares it with RHS for
/// the validity of the less-than relationship.
///
/// \returns true if *this < RHS when considered signed.
bool slt(int64_t RHS) const {
return getMinSignedBits() > 64 ? isNegative() : getSExtValue() < RHS;
}
/// \brief Unsigned less or equal comparison
///
/// Regards both *this and RHS as unsigned quantities and compares them for
/// validity of the less-or-equal relationship.
///
/// \returns true if *this <= RHS when both are considered unsigned.
bool ule(const APInt &RHS) const { return ult(RHS) || eq(RHS); }
/// \brief Unsigned less or equal comparison
///
/// Regards both *this as an unsigned quantity and compares it with RHS for
/// the validity of the less-or-equal relationship.
///
/// \returns true if *this <= RHS when considered unsigned.
bool ule(uint64_t RHS) const { return !ugt(RHS); }
/// \brief Signed less or equal comparison
///
/// Regards both *this and RHS as signed quantities and compares them for
/// validity of the less-or-equal relationship.
///
/// \returns true if *this <= RHS when both are considered signed.
bool sle(const APInt &RHS) const { return slt(RHS) || eq(RHS); }
/// \brief Signed less or equal comparison
///
/// Regards both *this as a signed quantity and compares it with RHS for the
/// validity of the less-or-equal relationship.
///
/// \returns true if *this <= RHS when considered signed.
bool sle(uint64_t RHS) const { return !sgt(RHS); }
/// \brief Unsigned greather than comparison
///
/// Regards both *this and RHS as unsigned quantities and compares them for
/// the validity of the greater-than relationship.
///
/// \returns true if *this > RHS when both are considered unsigned.
bool ugt(const APInt &RHS) const { return !ult(RHS) && !eq(RHS); }
/// \brief Unsigned greater than comparison
///
/// Regards both *this as an unsigned quantity and compares it with RHS for
/// the validity of the greater-than relationship.
///
/// \returns true if *this > RHS when considered unsigned.
bool ugt(uint64_t RHS) const {
return getActiveBits() > 64 ? true : getZExtValue() > RHS;
}
/// \brief Signed greather than comparison
///
/// Regards both *this and RHS as signed quantities and compares them for the
/// validity of the greater-than relationship.
///
/// \returns true if *this > RHS when both are considered signed.
bool sgt(const APInt &RHS) const { return !slt(RHS) && !eq(RHS); }
/// \brief Signed greater than comparison
///
/// Regards both *this as a signed quantity and compares it with RHS for
/// the validity of the greater-than relationship.
///
/// \returns true if *this > RHS when considered signed.
bool sgt(int64_t RHS) const {
return getMinSignedBits() > 64 ? !isNegative() : getSExtValue() > RHS;
}
/// \brief Unsigned greater or equal comparison
///
/// Regards both *this and RHS as unsigned quantities and compares them for
/// validity of the greater-or-equal relationship.
///
/// \returns true if *this >= RHS when both are considered unsigned.
bool uge(const APInt &RHS) const { return !ult(RHS); }
/// \brief Unsigned greater or equal comparison
///
/// Regards both *this as an unsigned quantity and compares it with RHS for
/// the validity of the greater-or-equal relationship.
///
/// \returns true if *this >= RHS when considered unsigned.
bool uge(uint64_t RHS) const { return !ult(RHS); }
/// \brief Signed greather or equal comparison
///
/// Regards both *this and RHS as signed quantities and compares them for
/// validity of the greater-or-equal relationship.
///
/// \returns true if *this >= RHS when both are considered signed.
bool sge(const APInt &RHS) const { return !slt(RHS); }
/// \brief Signed greater or equal comparison
///
/// Regards both *this as a signed quantity and compares it with RHS for
/// the validity of the greater-or-equal relationship.
///
/// \returns true if *this >= RHS when considered signed.
bool sge(int64_t RHS) const { return !slt(RHS); }
/// This operation tests if there are any pairs of corresponding bits
/// between this APInt and RHS that are both set.
bool intersects(const APInt &RHS) const { return (*this & RHS) != 0; }
/// @}
/// \name Resizing Operators
/// @{
/// \brief Truncate to new width.
///
/// Truncate the APInt to a specified width. It is an error to specify a width
/// that is greater than or equal to the current width.
APInt trunc(unsigned width) const;
/// \brief Sign extend to a new width.
///
/// This operation sign extends the APInt to a new width. If the high order
/// bit is set, the fill on the left will be done with 1 bits, otherwise zero.
/// It is an error to specify a width that is less than or equal to the
/// current width.
APInt sext(unsigned width) const;
/// \brief Zero extend to a new width.
///
/// This operation zero extends the APInt to a new width. The high order bits
/// are filled with 0 bits. It is an error to specify a width that is less
/// than or equal to the current width.
APInt zext(unsigned width) const;
/// \brief Sign extend or truncate to width
///
/// Make this APInt have the bit width given by \p width. The value is sign
/// extended, truncated, or left alone to make it that width.
APInt sextOrTrunc(unsigned width) const;
/// \brief Zero extend or truncate to width
///
/// Make this APInt have the bit width given by \p width. The value is zero
/// extended, truncated, or left alone to make it that width.
APInt zextOrTrunc(unsigned width) const;
/// \brief Sign extend or truncate to width
///
/// Make this APInt have the bit width given by \p width. The value is sign
/// extended, or left alone to make it that width.
APInt sextOrSelf(unsigned width) const;
/// \brief Zero extend or truncate to width
///
/// Make this APInt have the bit width given by \p width. The value is zero
/// extended, or left alone to make it that width.
APInt zextOrSelf(unsigned width) const;
/// @}
/// \name Bit Manipulation Operators
/// @{
/// \brief Set every bit to 1.
void setAllBits() {
if (isSingleWord())
VAL = UINT64_MAX;
else {
// Set all the bits in all the words.
for (unsigned i = 0; i < getNumWords(); ++i)
pVal[i] = UINT64_MAX;
}
// Clear the unused ones
clearUnusedBits();
}
/// \brief Set a given bit to 1.
///
/// Set the given bit to 1 whose position is given as "bitPosition".
void setBit(unsigned bitPosition);
/// \brief Set every bit to 0.
void clearAllBits() {
if (isSingleWord())
VAL = 0;
else
memset(pVal, 0, getNumWords() * APINT_WORD_SIZE);
}
/// \brief Set a given bit to 0.
///
/// Set the given bit to 0 whose position is given as "bitPosition".
void clearBit(unsigned bitPosition);
/// \brief Toggle every bit to its opposite value.
void flipAllBits() {
if (isSingleWord())
VAL ^= UINT64_MAX;
else {
for (unsigned i = 0; i < getNumWords(); ++i)
pVal[i] ^= UINT64_MAX;
}
clearUnusedBits();
}
/// \brief Toggles a given bit to its opposite value.
///
/// Toggle a given bit to its opposite value whose position is given
/// as "bitPosition".
void flipBit(unsigned bitPosition);
/// @}
/// \name Value Characterization Functions
/// @{
/// \brief Return the number of bits in the APInt.
unsigned getBitWidth() const { return BitWidth; }
/// \brief Get the number of words.
///
/// Here one word's bitwidth equals to that of uint64_t.
///
/// \returns the number of words to hold the integer value of this APInt.
unsigned getNumWords() const { return getNumWords(BitWidth); }
/// \brief Get the number of words.
///
/// *NOTE* Here one word's bitwidth equals to that of uint64_t.
///
/// \returns the number of words to hold the integer value with a given bit
/// width.
static unsigned getNumWords(unsigned BitWidth) {
return ((uint64_t)BitWidth + APINT_BITS_PER_WORD - 1) / APINT_BITS_PER_WORD;
}
/// \brief Compute the number of active bits in the value
///
/// This function returns the number of active bits which is defined as the
/// bit width minus the number of leading zeros. This is used in several
/// computations to see how "wide" the value is.
unsigned getActiveBits() const { return BitWidth - countLeadingZeros(); }
/// \brief Compute the number of active words in the value of this APInt.
///
/// This is used in conjunction with getActiveData to extract the raw value of
/// the APInt.
unsigned getActiveWords() const {
unsigned numActiveBits = getActiveBits();
return numActiveBits ? whichWord(numActiveBits - 1) + 1 : 1;
}
/// \brief Get the minimum bit size for this signed APInt
///
/// Computes the minimum bit width for this APInt while considering it to be a
/// signed (and probably negative) value. If the value is not negative, this
/// function returns the same value as getActiveBits()+1. Otherwise, it
/// returns the smallest bit width that will retain the negative value. For
/// example, -1 can be written as 0b1 or 0xFFFFFFFFFF. 0b1 is shorter and so
/// for -1, this function will always return 1.
unsigned getMinSignedBits() const {
if (isNegative())
return BitWidth - countLeadingOnes() + 1;
return getActiveBits() + 1;
}
/// \brief Get zero extended value
///
/// This method attempts to return the value of this APInt as a zero extended
/// uint64_t. The bitwidth must be <= 64 or the value must fit within a
/// uint64_t. Otherwise an assertion will result.
uint64_t getZExtValue() const {
if (isSingleWord())
return VAL;
assert(getActiveBits() <= 64 && "Too many bits for uint64_t");
return pVal[0];
}
/// \brief Get sign extended value
///
/// This method attempts to return the value of this APInt as a sign extended
/// int64_t. The bit width must be <= 64 or the value must fit within an
/// int64_t. Otherwise an assertion will result.
int64_t getSExtValue() const {
if (isSingleWord())
return int64_t(VAL << (APINT_BITS_PER_WORD - BitWidth)) >>
(APINT_BITS_PER_WORD - BitWidth);
assert(getMinSignedBits() <= 64 && "Too many bits for int64_t");
return int64_t(pVal[0]);
}
/// \brief Get bits required for string value.
///
/// This method determines how many bits are required to hold the APInt
/// equivalent of the string given by \p str.
static unsigned getBitsNeeded(StringRef str, uint8_t radix);
/// \brief The APInt version of the countLeadingZeros functions in
/// MathExtras.h.
///
/// It counts the number of zeros from the most significant bit to the first
/// one bit.
///
/// \returns BitWidth if the value is zero, otherwise returns the number of
/// zeros from the most significant bit to the first one bits.
unsigned countLeadingZeros() const {
if (isSingleWord()) {
unsigned unusedBits = APINT_BITS_PER_WORD - BitWidth;
return llvm::countLeadingZeros(VAL) - unusedBits;
}
return countLeadingZerosSlowCase();
}
/// \brief Count the number of leading one bits.
///
/// This function is an APInt version of the countLeadingOnes
/// functions in MathExtras.h. It counts the number of ones from the most
/// significant bit to the first zero bit.
///
/// \returns 0 if the high order bit is not set, otherwise returns the number
/// of 1 bits from the most significant to the least
unsigned countLeadingOnes() const;
/// Computes the number of leading bits of this APInt that are equal to its
/// sign bit.
unsigned getNumSignBits() const {
return isNegative() ? countLeadingOnes() : countLeadingZeros();
}
/// \brief Count the number of trailing zero bits.
///
/// This function is an APInt version of the countTrailingZeros
/// functions in MathExtras.h. It counts the number of zeros from the least
/// significant bit to the first set bit.
///
/// \returns BitWidth if the value is zero, otherwise returns the number of
/// zeros from the least significant bit to the first one bit.
unsigned countTrailingZeros() const;
/// \brief Count the number of trailing one bits.
///
/// This function is an APInt version of the countTrailingOnes
/// functions in MathExtras.h. It counts the number of ones from the least
/// significant bit to the first zero bit.
///
/// \returns BitWidth if the value is all ones, otherwise returns the number
/// of ones from the least significant bit to the first zero bit.
unsigned countTrailingOnes() const {
if (isSingleWord())
return llvm::countTrailingOnes(VAL);
return countTrailingOnesSlowCase();
}
/// \brief Count the number of bits set.
///
/// This function is an APInt version of the countPopulation functions
/// in MathExtras.h. It counts the number of 1 bits in the APInt value.
///
/// \returns 0 if the value is zero, otherwise returns the number of set bits.
unsigned countPopulation() const {
if (isSingleWord())
return llvm::countPopulation(VAL);
return countPopulationSlowCase();
}
/// @}
/// \name Conversion Functions
/// @{
void print(raw_ostream &OS, bool isSigned) const;
/// Converts an APInt to a string and append it to Str. Str is commonly a
/// SmallString.
void toString(SmallVectorImpl<char> &Str, unsigned Radix, bool Signed,
bool formatAsCLiteral = false) const;
/// Considers the APInt to be unsigned and converts it into a string in the
/// radix given. The radix can be 2, 8, 10 16, or 36.
void toStringUnsigned(SmallVectorImpl<char> &Str, unsigned Radix = 10) const {
toString(Str, Radix, false, false);
}
/// Considers the APInt to be signed and converts it into a string in the
/// radix given. The radix can be 2, 8, 10, 16, or 36.
void toStringSigned(SmallVectorImpl<char> &Str, unsigned Radix = 10) const {
toString(Str, Radix, true, false);
}
/// \brief Return the APInt as a std::string.
///
/// Note that this is an inefficient method. It is better to pass in a
/// SmallVector/SmallString to the methods above to avoid thrashing the heap
/// for the string.
std::string toString(unsigned Radix, bool Signed) const;
/// \returns a byte-swapped representation of this APInt Value.
APInt byteSwap() const;
/// \returns the value with the bit representation reversed of this APInt
/// Value.
APInt reverseBits() const;
/// \brief Converts this APInt to a double value.
double roundToDouble(bool isSigned) const;
/// \brief Converts this unsigned APInt to a double value.
double roundToDouble() const { return roundToDouble(false); }
/// \brief Converts this signed APInt to a double value.
double signedRoundToDouble() const { return roundToDouble(true); }
/// \brief Converts APInt bits to a double
///
/// The conversion does not do a translation from integer to double, it just
/// re-interprets the bits as a double. Note that it is valid to do this on
/// any bit width. Exactly 64 bits will be translated.
double bitsToDouble() const {
union {
uint64_t I;
double D;
} T;
T.I = (isSingleWord() ? VAL : pVal[0]);
return T.D;
}
/// \brief Converts APInt bits to a double
///
/// The conversion does not do a translation from integer to float, it just
/// re-interprets the bits as a float. Note that it is valid to do this on
/// any bit width. Exactly 32 bits will be translated.
float bitsToFloat() const {
union {
unsigned I;
float F;
} T;
T.I = unsigned((isSingleWord() ? VAL : pVal[0]));
return T.F;
}
/// \brief Converts a double to APInt bits.
///
/// The conversion does not do a translation from double to integer, it just
/// re-interprets the bits of the double.
static APInt doubleToBits(double V) {
union {
uint64_t I;
double D;
} T;
T.D = V;
return APInt(sizeof T * CHAR_BIT, T.I);
}
/// \brief Converts a float to APInt bits.
///
/// The conversion does not do a translation from float to integer, it just
/// re-interprets the bits of the float.
static APInt floatToBits(float V) {
union {
unsigned I;
float F;
} T;
T.F = V;
return APInt(sizeof T * CHAR_BIT, T.I);
}
/// @}
/// \name Mathematics Operations
/// @{
/// \returns the floor log base 2 of this APInt.
unsigned logBase2() const { return BitWidth - 1 - countLeadingZeros(); }
/// \returns the ceil log base 2 of this APInt.
unsigned ceilLogBase2() const {
APInt temp(*this);
--temp;
return BitWidth - temp.countLeadingZeros();
}
/// \returns the nearest log base 2 of this APInt. Ties round up.
///
/// NOTE: When we have a BitWidth of 1, we define:
///
/// log2(0) = UINT32_MAX
/// log2(1) = 0
///
/// to get around any mathematical concerns resulting from
/// referencing 2 in a space where 2 does no exist.
unsigned nearestLogBase2() const {
// Special case when we have a bitwidth of 1. If VAL is 1, then we
// get 0. If VAL is 0, we get UINT64_MAX which gets truncated to
// UINT32_MAX.
if (BitWidth == 1)
return VAL - 1;
// Handle the zero case.
if (!getBoolValue())
return UINT32_MAX;
// The non-zero case is handled by computing:
//
// nearestLogBase2(x) = logBase2(x) + x[logBase2(x)-1].
//
// where x[i] is referring to the value of the ith bit of x.
unsigned lg = logBase2();
return lg + unsigned((*this)[lg - 1]);
}
/// \returns the log base 2 of this APInt if its an exact power of two, -1
/// otherwise
int32_t exactLogBase2() const {
if (!isPowerOf2())
return -1;
return logBase2();
}
/// \brief Compute the square root
APInt sqrt() const;
/// \brief Get the absolute value;
///
/// If *this is < 0 then return -(*this), otherwise *this;
APInt abs() const {
if (isNegative())
return -(*this);
return *this;
}
/// \returns the multiplicative inverse for a given modulo.
APInt multiplicativeInverse(const APInt &modulo) const;
/// @}
/// \name Support for division by constant
/// @{
/// Calculate the magic number for signed division by a constant.
struct ms;
ms magic() const;
/// Calculate the magic number for unsigned division by a constant.
struct mu;
mu magicu(unsigned LeadingZeros = 0) const;
/// @}
/// \name Building-block Operations for APInt and APFloat
/// @{
// These building block operations operate on a representation of arbitrary
// precision, two's-complement, bignum integer values. They should be
// sufficient to implement APInt and APFloat bignum requirements. Inputs are
// generally a pointer to the base of an array of integer parts, representing
// an unsigned bignum, and a count of how many parts there are.
/// Sets the least significant part of a bignum to the input value, and zeroes
/// out higher parts.
static void tcSet(integerPart *, integerPart, unsigned int);
/// Assign one bignum to another.
static void tcAssign(integerPart *, const integerPart *, unsigned int);
/// Returns true if a bignum is zero, false otherwise.
static bool tcIsZero(const integerPart *, unsigned int);
/// Extract the given bit of a bignum; returns 0 or 1. Zero-based.
static int tcExtractBit(const integerPart *, unsigned int bit);
/// Copy the bit vector of width srcBITS from SRC, starting at bit srcLSB, to
/// DST, of dstCOUNT parts, such that the bit srcLSB becomes the least
/// significant bit of DST. All high bits above srcBITS in DST are
/// zero-filled.
static void tcExtract(integerPart *, unsigned int dstCount,
const integerPart *, unsigned int srcBits,
unsigned int srcLSB);
/// Set the given bit of a bignum. Zero-based.
static void tcSetBit(integerPart *, unsigned int bit);
/// Clear the given bit of a bignum. Zero-based.
static void tcClearBit(integerPart *, unsigned int bit);
/// Returns the bit number of the least or most significant set bit of a
/// number. If the input number has no bits set -1U is returned.
static unsigned int tcLSB(const integerPart *, unsigned int);
static unsigned int tcMSB(const integerPart *parts, unsigned int n);
/// Negate a bignum in-place.
static void tcNegate(integerPart *, unsigned int);
/// DST += RHS + CARRY where CARRY is zero or one. Returns the carry flag.
static integerPart tcAdd(integerPart *, const integerPart *,
integerPart carry, unsigned);
/// DST -= RHS + CARRY where CARRY is zero or one. Returns the carry flag.
static integerPart tcSubtract(integerPart *, const integerPart *,
integerPart carry, unsigned);
/// DST += SRC * MULTIPLIER + PART if add is true
/// DST = SRC * MULTIPLIER + PART if add is false
///
/// Requires 0 <= DSTPARTS <= SRCPARTS + 1. If DST overlaps SRC they must
/// start at the same point, i.e. DST == SRC.
///
/// If DSTPARTS == SRC_PARTS + 1 no overflow occurs and zero is returned.
/// Otherwise DST is filled with the least significant DSTPARTS parts of the
/// result, and if all of the omitted higher parts were zero return zero,
/// otherwise overflow occurred and return one.
static int tcMultiplyPart(integerPart *dst, const integerPart *src,
integerPart multiplier, integerPart carry,
unsigned int srcParts, unsigned int dstParts,
bool add);
/// DST = LHS * RHS, where DST has the same width as the operands and is
/// filled with the least significant parts of the result. Returns one if
/// overflow occurred, otherwise zero. DST must be disjoint from both
/// operands.
static int tcMultiply(integerPart *, const integerPart *, const integerPart *,
unsigned);
/// DST = LHS * RHS, where DST has width the sum of the widths of the
/// operands. No overflow occurs. DST must be disjoint from both
/// operands. Returns the number of parts required to hold the result.
static unsigned int tcFullMultiply(integerPart *, const integerPart *,
const integerPart *, unsigned, unsigned);
/// If RHS is zero LHS and REMAINDER are left unchanged, return one.
/// Otherwise set LHS to LHS / RHS with the fractional part discarded, set
/// REMAINDER to the remainder, return zero. i.e.
///
/// OLD_LHS = RHS * LHS + REMAINDER
///
/// SCRATCH is a bignum of the same size as the operands and result for use by
/// the routine; its contents need not be initialized and are destroyed. LHS,
/// REMAINDER and SCRATCH must be distinct.
static int tcDivide(integerPart *lhs, const integerPart *rhs,
integerPart *remainder, integerPart *scratch,
unsigned int parts);
/// Shift a bignum left COUNT bits. Shifted in bits are zero. There are no
/// restrictions on COUNT.
static void tcShiftLeft(integerPart *, unsigned int parts,
unsigned int count);
/// Shift a bignum right COUNT bits. Shifted in bits are zero. There are no
/// restrictions on COUNT.
static void tcShiftRight(integerPart *, unsigned int parts,
unsigned int count);
/// The obvious AND, OR and XOR and complement operations.
static void tcAnd(integerPart *, const integerPart *, unsigned int);
static void tcOr(integerPart *, const integerPart *, unsigned int);
static void tcXor(integerPart *, const integerPart *, unsigned int);
static void tcComplement(integerPart *, unsigned int);
/// Comparison (unsigned) of two bignums.
static int tcCompare(const integerPart *, const integerPart *, unsigned int);
/// Increment a bignum in-place. Return the carry flag.
static integerPart tcIncrement(integerPart *, unsigned int);
/// Decrement a bignum in-place. Return the borrow flag.
static integerPart tcDecrement(integerPart *, unsigned int);
/// Set the least significant BITS and clear the rest.
static void tcSetLeastSignificantBits(integerPart *, unsigned int,
unsigned int bits);
/// \brief debug method
void dump() const;
/// @}
};
/// Magic data for optimising signed division by a constant.
struct APInt::ms {
APInt m; ///< magic number
unsigned s; ///< shift amount
};
/// Magic data for optimising unsigned division by a constant.
struct APInt::mu {
APInt m; ///< magic number
bool a; ///< add indicator
unsigned s; ///< shift amount
};
inline bool operator==(uint64_t V1, const APInt &V2) { return V2 == V1; }
inline bool operator!=(uint64_t V1, const APInt &V2) { return V2 != V1; }
inline raw_ostream &operator<<(raw_ostream &OS, const APInt &I) {
I.print(OS, true);
return OS;
}
inline APInt operator-(APInt v) {
v.flipAllBits();
++v;
return v;
}
inline APInt operator+(APInt a, const APInt &b) {
a += b;
return a;
}
inline APInt operator+(const APInt &a, APInt &&b) {
b += a;
return std::move(b);
}
inline APInt operator+(APInt a, uint64_t RHS) {
a += RHS;
return a;
}
inline APInt operator+(uint64_t LHS, APInt b) {
b += LHS;
return b;
}
inline APInt operator-(APInt a, const APInt &b) {
a -= b;
return a;
}
inline APInt operator-(const APInt &a, APInt &&b) {
b = -std::move(b);
b += a;
return std::move(b);
}
inline APInt operator-(APInt a, uint64_t RHS) {
a -= RHS;
return a;
}
inline APInt operator-(uint64_t LHS, APInt b) {
b = -std::move(b);
b += LHS;
return b;
}
namespace APIntOps {
/// \brief Determine the smaller of two APInts considered to be signed.
inline const APInt &smin(const APInt &A, const APInt &B) {
return A.slt(B) ? A : B;
}
/// \brief Determine the larger of two APInts considered to be signed.
inline const APInt &smax(const APInt &A, const APInt &B) {
return A.sgt(B) ? A : B;
}
/// \brief Determine the smaller of two APInts considered to be signed.
inline const APInt &umin(const APInt &A, const APInt &B) {
return A.ult(B) ? A : B;
}
/// \brief Determine the larger of two APInts considered to be unsigned.
inline const APInt &umax(const APInt &A, const APInt &B) {
return A.ugt(B) ? A : B;
}
/// \brief Check if the specified APInt has a N-bits unsigned integer value.
inline bool isIntN(unsigned N, const APInt &APIVal) { return APIVal.isIntN(N); }
/// \brief Check if the specified APInt has a N-bits signed integer value.
inline bool isSignedIntN(unsigned N, const APInt &APIVal) {
return APIVal.isSignedIntN(N);
}
/// \returns true if the argument APInt value is a sequence of ones starting at
/// the least significant bit with the remainder zero.
inline bool isMask(unsigned numBits, const APInt &APIVal) {
return numBits <= APIVal.getBitWidth() &&
APIVal == APInt::getLowBitsSet(APIVal.getBitWidth(), numBits);
}
/// \returns true if the argument is a non-empty sequence of ones starting at
/// the least significant bit with the remainder zero (32 bit version).
/// Ex. isMask(0x0000FFFFU) == true.
inline bool isMask(const APInt &Value) {
return (Value != 0) && ((Value + 1) & Value) == 0;
}
/// \brief Return true if the argument APInt value contains a sequence of ones
/// with the remainder zero.
inline bool isShiftedMask(unsigned numBits, const APInt &APIVal) {
return isMask(numBits, (APIVal - APInt(numBits, 1)) | APIVal);
}
/// \brief Returns a byte-swapped representation of the specified APInt Value.
inline APInt byteSwap(const APInt &APIVal) { return APIVal.byteSwap(); }
/// \brief Returns the floor log base 2 of the specified APInt value.
inline unsigned logBase2(const APInt &APIVal) { return APIVal.logBase2(); }
/// \brief Compute GCD of two APInt values.
///
/// This function returns the greatest common divisor of the two APInt values
/// using Euclid's algorithm.
///
/// \returns the greatest common divisor of Val1 and Val2
APInt GreatestCommonDivisor(const APInt &Val1, const APInt &Val2);
/// \brief Converts the given APInt to a double value.
///
/// Treats the APInt as an unsigned value for conversion purposes.
inline double RoundAPIntToDouble(const APInt &APIVal) {
return APIVal.roundToDouble();
}
/// \brief Converts the given APInt to a double value.
///
/// Treats the APInt as a signed value for conversion purposes.
inline double RoundSignedAPIntToDouble(const APInt &APIVal) {
return APIVal.signedRoundToDouble();
}
/// \brief Converts the given APInt to a float vlalue.
inline float RoundAPIntToFloat(const APInt &APIVal) {
return float(RoundAPIntToDouble(APIVal));
}
/// \brief Converts the given APInt to a float value.
///
/// Treast the APInt as a signed value for conversion purposes.
inline float RoundSignedAPIntToFloat(const APInt &APIVal) {
return float(APIVal.signedRoundToDouble());
}
/// \brief Converts the given double value into a APInt.
///
/// This function convert a double value to an APInt value.
APInt RoundDoubleToAPInt(double Double, unsigned width);
/// \brief Converts a float value into a APInt.
///
/// Converts a float value into an APInt value.
inline APInt RoundFloatToAPInt(float Float, unsigned width) {
return RoundDoubleToAPInt(double(Float), width);
}
/// \brief Arithmetic right-shift function.
///
/// Arithmetic right-shift the APInt by shiftAmt.
inline APInt ashr(const APInt &LHS, unsigned shiftAmt) {
return LHS.ashr(shiftAmt);
}
/// \brief Logical right-shift function.
///
/// Logical right-shift the APInt by shiftAmt.
inline APInt lshr(const APInt &LHS, unsigned shiftAmt) {
return LHS.lshr(shiftAmt);
}
/// \brief Left-shift function.
///
/// Left-shift the APInt by shiftAmt.
inline APInt shl(const APInt &LHS, unsigned shiftAmt) {
return LHS.shl(shiftAmt);
}
/// \brief Signed division function for APInt.
///
/// Signed divide APInt LHS by APInt RHS.
inline APInt sdiv(const APInt &LHS, const APInt &RHS) { return LHS.sdiv(RHS); }
/// \brief Unsigned division function for APInt.
///
/// Unsigned divide APInt LHS by APInt RHS.
inline APInt udiv(const APInt &LHS, const APInt &RHS) { return LHS.udiv(RHS); }
/// \brief Function for signed remainder operation.
///
/// Signed remainder operation on APInt.
inline APInt srem(const APInt &LHS, const APInt &RHS) { return LHS.srem(RHS); }
/// \brief Function for unsigned remainder operation.
///
/// Unsigned remainder operation on APInt.
inline APInt urem(const APInt &LHS, const APInt &RHS) { return LHS.urem(RHS); }
/// \brief Function for multiplication operation.
///
/// Performs multiplication on APInt values.
inline APInt mul(const APInt &LHS, const APInt &RHS) { return LHS * RHS; }
/// \brief Function for addition operation.
///
/// Performs addition on APInt values.
inline APInt add(const APInt &LHS, const APInt &RHS) { return LHS + RHS; }
/// \brief Function for subtraction operation.
///
/// Performs subtraction on APInt values.
inline APInt sub(const APInt &LHS, const APInt &RHS) { return LHS - RHS; }
/// \brief Bitwise AND function for APInt.
///
/// Performs bitwise AND operation on APInt LHS and
/// APInt RHS.
inline APInt And(const APInt &LHS, const APInt &RHS) { return LHS & RHS; }
/// \brief Bitwise OR function for APInt.
///
/// Performs bitwise OR operation on APInt LHS and APInt RHS.
inline APInt Or(const APInt &LHS, const APInt &RHS) { return LHS | RHS; }
/// \brief Bitwise XOR function for APInt.
///
/// Performs bitwise XOR operation on APInt.
inline APInt Xor(const APInt &LHS, const APInt &RHS) { return LHS ^ RHS; }
/// \brief Bitwise complement function.
///
/// Performs a bitwise complement operation on APInt.
inline APInt Not(const APInt &APIVal) { return ~APIVal; }
} // End of APIntOps namespace
// See friend declaration above. This additional declaration is required in
// order to compile LLVM with IBM xlC compiler.
hash_code hash_value(const APInt &Arg);
} // End of llvm namespace
#endif