llvm-6502/include/llvm/ADT/APInt.h
Reid Spencer 57ae4f5f01 Implement a getBitsNeeded method to determine how many bits are needed to
represent a string in binary form by an APInt.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35968 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-13 19:19:07 +00:00

1190 lines
43 KiB
C++

//===-- llvm/Support/APInt.h - For Arbitrary Precision Integer -*- C++ -*--===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Sheng Zhou and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements a class to represent arbitrary precision integral
// constant values and operations on them.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_APINT_H
#define LLVM_APINT_H
#include "llvm/Support/DataTypes.h"
#include <cassert>
#include <string>
namespace llvm {
//===----------------------------------------------------------------------===//
// APInt Class
//===----------------------------------------------------------------------===//
/// APInt - This class represents arbitrary precision constant integral values.
/// It 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.
///
/// @brief Class for arbitrary precision integers.
class APInt {
uint32_t 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 {
APINT_BITS_PER_WORD = sizeof(uint64_t) * 8, ///< Bits in a word
APINT_WORD_SIZE = sizeof(uint64_t) ///< Byte size of a word
};
/// This constructor is used only internally for speed of construction of
/// temporaries. It is unsafe for general use so it is not public.
/// @brief Fast internal constructor
APInt(uint64_t* val, uint32_t bits) : BitWidth(bits), pVal(val) { }
/// @returns true if the number of bits <= 64, false otherwise.
/// @brief Determine if this APInt just has one word to store value.
inline bool isSingleWord() const {
return BitWidth <= APINT_BITS_PER_WORD;
}
/// @returns the word position for the specified bit position.
/// @brief Determine which word a bit is in.
static inline uint32_t whichWord(uint32_t bitPosition) {
return bitPosition / APINT_BITS_PER_WORD;
}
/// @returns the bit position in a word for the specified bit position
/// in the APInt.
/// @brief Determine which bit in a word a bit is in.
static inline uint32_t whichBit(uint32_t bitPosition) {
return bitPosition % APINT_BITS_PER_WORD;
}
/// 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.
/// @returns a uint64_t with only bit at "whichBit(bitPosition)" set
/// @brief Get a single bit mask.
static inline uint64_t maskBit(uint32_t bitPosition) {
return 1ULL << whichBit(bitPosition);
}
/// This method is used internally to clear the to "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.
/// @brief Clear unused high order bits
inline APInt& clearUnusedBits() {
// Compute how many bits are used in the final word
uint32_t 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 shfit is the same size as
// the word size (64).
return *this;
// Mask out the hight bits.
uint64_t mask = ~uint64_t(0ULL) >> (APINT_BITS_PER_WORD - wordBits);
if (isSingleWord())
VAL &= mask;
else
pVal[getNumWords() - 1] &= mask;
return *this;
}
/// @returns the corresponding word for the specified bit position.
/// @brief Get the word corresponding to a bit position
inline uint64_t getWord(uint32_t bitPosition) const {
return isSingleWord() ? VAL : pVal[whichWord(bitPosition)];
}
/// This is used by the constructors that take string arguments.
/// @brief Convert a char array into an APInt
void fromString(uint32_t numBits, const char *strStart, uint32_t slen,
uint8_t radix);
/// 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.
/// @brief An internal division function for dividing APInts.
static void divide(const APInt LHS, uint32_t lhsWords,
const APInt &RHS, uint32_t rhsWords,
APInt *Quotient, APInt *Remainder);
#ifndef NDEBUG
/// @brief debug method
void dump() const;
#endif
public:
/// @name Constructors
/// @{
/// 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
/// @brief Create a new APInt of numBits width, initialized as val.
APInt(uint32_t numBits, uint64_t val, bool isSigned = false);
/// Note that numWords 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 numWords the number of words in bigVal
/// @param bigVal a sequence of words to form the initial value of the APInt
/// @brief Construct an APInt of numBits width, initialized as bigVal[].
APInt(uint32_t numBits, uint32_t numWords, uint64_t bigVal[]);
/// This constructor interprets Val as a string in the given radix. The
/// interpretation stops when the first charater that is not suitable for the
/// radix is encountered. Acceptable radix values are 2, 8, 10 and 16. 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 val the string to be interpreted
/// @param radix the radix of Val to use for the intepretation
/// @brief Construct an APInt from a string representation.
APInt(uint32_t numBits, const std::string& val, uint8_t radix);
/// This constructor interprets the slen characters starting at StrStart as
/// a string in the given radix. The interpretation stops when the first
/// character that is not suitable for the radix is encountered. Acceptable
/// radix values are 2, 8, 10 and 16. 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 strStart the start of the string to be interpreted
/// @param slen the maximum number of characters to interpret
/// @brief Construct an APInt from a string representation.
APInt(uint32_t numBits, const char strStart[], uint32_t slen, uint8_t radix);
/// Simply makes *this a copy of that.
/// @brief Copy Constructor.
APInt(const APInt& that);
/// @brief Destructor.
~APInt();
/// @}
/// @name Value Tests
/// @{
/// This tests the high bit of this APInt to determine if it is set.
/// @returns true if this APInt is negative, false otherwise
/// @brief Determine sign of this APInt.
bool isNegative() const {
return (*this)[BitWidth - 1];
}
/// This tests the high bit of the APInt to determine if it is unset.
/// @brief Determine if this APInt Value is positive (not negative).
bool isPositive() const {
return !isNegative();
}
/// This tests if the value of this APInt is strictly positive (> 0).
/// @returns true if this APInt is Positive and not zero.
/// @brief Determine if this APInt Value is strictly positive.
inline bool isStrictlyPositive() const {
return isPositive() && (*this) != 0;
}
/// This checks to see if the value has all bits of the APInt are set or not.
/// @brief Determine if all bits are set
inline bool isAllOnesValue() const {
return countPopulation() == BitWidth;
}
/// This checks to see if the value of this APInt is the maximum unsigned
/// value for the APInt's bit width.
/// @brief Determine if this is the largest unsigned value.
bool isMaxValue() const {
return countPopulation() == BitWidth;
}
/// This checks to see if the value of this APInt is the maximum signed
/// value for the APInt's bit width.
/// @brief Determine if this is the largest signed value.
bool isMaxSignedValue() const {
return BitWidth == 1 ? VAL == 0 :
!isNegative() && countPopulation() == BitWidth - 1;
}
/// This checks to see if the value of this APInt is the minimum unsigned
/// value for the APInt's bit width.
/// @brief Determine if this is the smallest unsigned value.
bool isMinValue() const {
return countPopulation() == 0;
}
/// This checks to see if the value of this APInt is the minimum signed
/// value for the APInt's bit width.
/// @brief Determine if this is the smallest signed value.
bool isMinSignedValue() const {
return BitWidth == 1 ? VAL == 1 :
isNegative() && countPopulation() == 1;
}
/// @brief Check if this APInt has an N-bits integer value.
inline bool isIntN(uint32_t N) const {
assert(N && "N == 0 ???");
if (isSingleWord()) {
return VAL == (VAL & (~0ULL >> (64 - N)));
} else {
APInt Tmp(N, getNumWords(), pVal);
return Tmp == (*this);
}
}
/// @returns true if the argument APInt value is a power of two > 0.
bool isPowerOf2() const;
/// isSignBit - Return true if this is the value returned by getSignBit.
bool isSignBit() const { return isMinSignedValue(); }
/// This converts the APInt to a boolean value as a test against zero.
/// @brief Boolean conversion function.
inline bool getBoolValue() const {
return *this != 0;
}
/// getLimitedValue - 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();
}
/// @}
/// @name Value Generators
/// @{
/// @brief Gets maximum unsigned value of APInt for specific bit width.
static APInt getMaxValue(uint32_t numBits) {
return APInt(numBits, 0).set();
}
/// @brief Gets maximum signed value of APInt for a specific bit width.
static APInt getSignedMaxValue(uint32_t numBits) {
return APInt(numBits, 0).set().clear(numBits - 1);
}
/// @brief Gets minimum unsigned value of APInt for a specific bit width.
static APInt getMinValue(uint32_t numBits) {
return APInt(numBits, 0);
}
/// @brief Gets minimum signed value of APInt for a specific bit width.
static APInt getSignedMinValue(uint32_t numBits) {
return APInt(numBits, 0).set(numBits - 1);
}
/// getSignBit - This is just a wrapper function of getSignedMinValue(), and
/// it helps code readability when we want to get a SignBit.
/// @brief Get the SignBit for a specific bit width.
inline static APInt getSignBit(uint32_t BitWidth) {
return getSignedMinValue(BitWidth);
}
/// @returns the all-ones value for an APInt of the specified bit-width.
/// @brief Get the all-ones value.
static APInt getAllOnesValue(uint32_t numBits) {
return APInt(numBits, 0).set();
}
/// @returns the '0' value for an APInt of the specified bit-width.
/// @brief Get the '0' value.
static APInt getNullValue(uint32_t numBits) {
return APInt(numBits, 0);
}
/// 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(uint32_t numBits) const;
/// 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(uint32_t numBits) const;
/// Constructs an APInt value that has a contiguous range of bits set. The
/// bits from loBit to hiBit will be set. All other bits will be zero. For
/// example, with parameters(32, 15, 0) you would get 0x0000FFFF. If hiBit is
/// less than loBit then the set bits "wrap". For example, with
/// parameters (32, 3, 28), 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.
/// @brief Get a value with a block of bits set.
static APInt getBitsSet(uint32_t numBits, uint32_t loBit, uint32_t hiBit) {
assert(hiBit < numBits && "hiBit out of range");
assert(loBit < numBits && "loBit out of range");
if (hiBit < loBit)
return getLowBitsSet(numBits, hiBit+1) |
getHighBitsSet(numBits, numBits-loBit+1);
return getLowBitsSet(numBits, hiBit-loBit+1).shl(loBit);
}
/// 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.
/// @brief Get a value with high bits set
static APInt getHighBitsSet(uint32_t numBits, uint32_t 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);
uint32_t shiftAmt = numBits - hiBitsSet;
// For small values, return quickly
if (numBits <= APINT_BITS_PER_WORD)
return APInt(numBits, ~0ULL << shiftAmt);
return (~APInt(numBits, 0)).shl(shiftAmt);
}
/// 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.
/// @brief Get a value with low bits set
static APInt getLowBitsSet(uint32_t numBits, uint32_t 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, -1ULL);
// For small values, return quickly
if (numBits < APINT_BITS_PER_WORD)
return APInt(numBits, (1ULL << loBitsSet) - 1);
return (~APInt(numBits, 0)).lshr(numBits - loBitsSet);
}
/// The hash value is computed as the sum of the words and the bit width.
/// @returns A hash value computed from the sum of the APInt words.
/// @brief Get a hash value based on this APInt
uint64_t getHashValue() const;
/// 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.
inline const uint64_t* getRawData() const {
if (isSingleWord())
return &VAL;
return &pVal[0];
}
/// @}
/// @name Unary Operators
/// @{
/// @returns a new APInt value representing *this incremented by one
/// @brief Postfix increment operator.
inline const APInt operator++(int) {
APInt API(*this);
++(*this);
return API;
}
/// @returns *this incremented by one
/// @brief Prefix increment operator.
APInt& operator++();
/// @returns a new APInt representing *this decremented by one.
/// @brief Postfix decrement operator.
inline const APInt operator--(int) {
APInt API(*this);
--(*this);
return API;
}
/// @returns *this decremented by one.
/// @brief Prefix decrement operator.
APInt& operator--();
/// Performs a bitwise complement operation on this APInt.
/// @returns an APInt that is the bitwise complement of *this
/// @brief Unary bitwise complement operator.
APInt operator~() const;
/// Negates *this using two's complement logic.
/// @returns An APInt value representing the negation of *this.
/// @brief Unary negation operator
inline APInt operator-() const {
return APInt(BitWidth, 0) - (*this);
}
/// Performs logical negation operation on this APInt.
/// @returns true if *this is zero, false otherwise.
/// @brief Logical negation operator.
bool operator !() const;
/// @}
/// @name Assignment Operators
/// @{
/// @returns *this after assignment of RHS.
/// @brief Copy assignment operator.
APInt& operator=(const APInt& RHS);
/// 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.
/// @brief Assignment operator.
APInt& operator=(uint64_t RHS);
/// Performs a bitwise AND operation on this APInt and RHS. The result is
/// assigned to *this.
/// @returns *this after ANDing with RHS.
/// @brief Bitwise AND assignment operator.
APInt& operator&=(const APInt& RHS);
/// Performs a bitwise OR operation on this APInt and RHS. The result is
/// assigned *this;
/// @returns *this after ORing with RHS.
/// @brief Bitwise OR assignment operator.
APInt& operator|=(const APInt& RHS);
/// Performs a bitwise XOR operation on this APInt and RHS. The result is
/// assigned to *this.
/// @returns *this after XORing with RHS.
/// @brief Bitwise XOR assignment operator.
APInt& operator^=(const APInt& RHS);
/// Multiplies this APInt by RHS and assigns the result to *this.
/// @returns *this
/// @brief Multiplication assignment operator.
APInt& operator*=(const APInt& RHS);
/// Adds RHS to *this and assigns the result to *this.
/// @returns *this
/// @brief Addition assignment operator.
APInt& operator+=(const APInt& RHS);
/// Subtracts RHS from *this and assigns the result to *this.
/// @returns *this
/// @brief Subtraction assignment operator.
APInt& operator-=(const APInt& RHS);
/// Shifts *this left by shiftAmt and assigns the result to *this.
/// @returns *this after shifting left by shiftAmt
/// @brief Left-shift assignment function.
inline APInt& operator<<=(uint32_t shiftAmt) {
*this = shl(shiftAmt);
return *this;
}
/// @}
/// @name Binary Operators
/// @{
/// Performs a bitwise AND operation on *this and RHS.
/// @returns An APInt value representing the bitwise AND of *this and RHS.
/// @brief Bitwise AND operator.
APInt operator&(const APInt& RHS) const;
APInt And(const APInt& RHS) const {
return this->operator&(RHS);
}
/// Performs a bitwise OR operation on *this and RHS.
/// @returns An APInt value representing the bitwise OR of *this and RHS.
/// @brief Bitwise OR operator.
APInt operator|(const APInt& RHS) const;
APInt Or(const APInt& RHS) const {
return this->operator|(RHS);
}
/// Performs a bitwise XOR operation on *this and RHS.
/// @returns An APInt value representing the bitwise XOR of *this and RHS.
/// @brief Bitwise XOR operator.
APInt operator^(const APInt& RHS) const;
APInt Xor(const APInt& RHS) const {
return this->operator^(RHS);
}
/// Multiplies this APInt by RHS and returns the result.
/// @brief Multiplication operator.
APInt operator*(const APInt& RHS) const;
/// Adds RHS to this APInt and returns the result.
/// @brief Addition operator.
APInt operator+(const APInt& RHS) const;
APInt operator+(uint64_t RHS) const {
return (*this) + APInt(BitWidth, RHS);
}
/// Subtracts RHS from this APInt and returns the result.
/// @brief Subtraction operator.
APInt operator-(const APInt& RHS) const;
APInt operator-(uint64_t RHS) const {
return (*this) - APInt(BitWidth, RHS);
}
APInt operator<<(unsigned Bits) const {
return shl(Bits);
}
/// Arithmetic right-shift this APInt by shiftAmt.
/// @brief Arithmetic right-shift function.
APInt ashr(uint32_t shiftAmt) const;
/// Logical right-shift this APInt by shiftAmt.
/// @brief Logical right-shift function.
APInt lshr(uint32_t shiftAmt) const;
/// Left-shift this APInt by shiftAmt.
/// @brief Left-shift function.
APInt shl(uint32_t shiftAmt) const;
/// 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
/// @brief Unsigned division operation.
APInt udiv(const APInt& RHS) const;
/// Signed divide this APInt by APInt RHS.
/// @brief Signed division function for APInt.
inline APInt sdiv(const APInt& RHS) const {
if (isNegative())
if (RHS.isNegative())
return (-(*this)).udiv(-RHS);
else
return -((-(*this)).udiv(RHS));
else if (RHS.isNegative())
return -(this->udiv(-RHS));
return this->udiv(RHS);
}
/// 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
/// @brief Unsigned remainder operation.
APInt urem(const APInt& RHS) const;
/// Signed remainder operation on APInt.
/// @brief Function for signed remainder operation.
inline APInt srem(const APInt& RHS) const {
if (isNegative())
if (RHS.isNegative())
return -((-(*this)).urem(-RHS));
else
return -((-(*this)).urem(RHS));
else if (RHS.isNegative())
return this->urem(-RHS);
return this->urem(RHS);
}
/// @returns the bit value at bitPosition
/// @brief Array-indexing support.
bool operator[](uint32_t bitPosition) const;
/// @}
/// @name Comparison Operators
/// @{
/// Compares this APInt with RHS for the validity of the equality
/// relationship.
/// @brief Equality operator.
bool operator==(const APInt& RHS) const;
/// Compares this APInt with a uint64_t for the validity of the equality
/// relationship.
/// @returns true if *this == Val
/// @brief Equality operator.
bool operator==(uint64_t Val) const;
/// Compares this APInt with RHS for the validity of the equality
/// relationship.
/// @returns true if *this == Val
/// @brief Equality comparison.
bool eq(const APInt &RHS) const {
return (*this) == RHS;
}
/// Compares this APInt with RHS for the validity of the inequality
/// relationship.
/// @returns true if *this != Val
/// @brief Inequality operator.
inline bool operator!=(const APInt& RHS) const {
return !((*this) == RHS);
}
/// Compares this APInt with a uint64_t for the validity of the inequality
/// relationship.
/// @returns true if *this != Val
/// @brief Inequality operator.
inline bool operator!=(uint64_t Val) const {
return !((*this) == Val);
}
/// Compares this APInt with RHS for the validity of the inequality
/// relationship.
/// @returns true if *this != Val
/// @brief Inequality comparison
bool ne(const APInt &RHS) const {
return !((*this) == RHS);
}
/// 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.
/// @brief Unsigned less than comparison
bool ult(const APInt& RHS) const;
/// 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.
/// @brief Signed less than comparison
bool slt(const APInt& RHS) const;
/// 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.
/// @brief Unsigned less or equal comparison
bool ule(const APInt& RHS) const {
return ult(RHS) || eq(RHS);
}
/// 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.
/// @brief Signed less or equal comparison
bool sle(const APInt& RHS) const {
return slt(RHS) || eq(RHS);
}
/// 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.
/// @brief Unsigned greather than comparison
bool ugt(const APInt& RHS) const {
return !ult(RHS) && !eq(RHS);
}
/// 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.
/// @brief Signed greather than comparison
bool sgt(const APInt& RHS) const {
return !slt(RHS) && !eq(RHS);
}
/// 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.
/// @brief Unsigned greater or equal comparison
bool uge(const APInt& RHS) const {
return !ult(RHS);
}
/// 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.
/// @brief Signed greather or equal comparison
bool sge(const APInt& RHS) const {
return !slt(RHS);
}
/// @}
/// @name Resizing Operators
/// @{
/// 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.
/// @brief Truncate to new width.
APInt &trunc(uint32_t 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.
/// @brief Sign extend to a new width.
APInt &sext(uint32_t 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.
/// @brief Zero extend to a new width.
APInt &zext(uint32_t 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.
/// @brief Sign extend or truncate to width
APInt &sextOrTrunc(uint32_t 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.
/// @brief Zero extend or truncate to width
APInt &zextOrTrunc(uint32_t width);
/// @}
/// @name Bit Manipulation Operators
/// @{
/// @brief Set every bit to 1.
APInt& set();
/// Set the given bit to 1 whose position is given as "bitPosition".
/// @brief Set a given bit to 1.
APInt& set(uint32_t bitPosition);
/// @brief Set every bit to 0.
APInt& clear();
/// Set the given bit to 0 whose position is given as "bitPosition".
/// @brief Set a given bit to 0.
APInt& clear(uint32_t bitPosition);
/// @brief Toggle every bit to its opposite value.
APInt& flip();
/// Toggle a given bit to its opposite value whose position is given
/// as "bitPosition".
/// @brief Toggles a given bit to its opposite value.
APInt& flip(uint32_t bitPosition);
/// @}
/// @name Value Characterization Functions
/// @{
/// @returns the total number of bits.
inline uint32_t getBitWidth() const {
return BitWidth;
}
/// Here one word's bitwidth equals to that of uint64_t.
/// @returns the number of words to hold the integer value of this APInt.
/// @brief Get the number of words.
inline uint32_t getNumWords() const {
return (BitWidth + APINT_BITS_PER_WORD - 1) / APINT_BITS_PER_WORD;
}
/// 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.
/// @brief Compute the number of active bits in the value
inline uint32_t getActiveBits() const {
return BitWidth - countLeadingZeros();
}
/// This function returns 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.
inline uint32_t getActiveWords() const {
return whichWord(getActiveBits()-1) + 1;
}
/// 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(). 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.
/// @brief Get the minimum bit size for this signed APInt
inline uint32_t getMinSignedBits() const {
if (isNegative())
return BitWidth - countLeadingOnes() + 1;
return getActiveBits();
}
/// 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.
/// @brief Get zero extended value
inline uint64_t getZExtValue() const {
if (isSingleWord())
return VAL;
assert(getActiveBits() <= 64 && "Too many bits for uint64_t");
return pVal[0];
}
/// 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.
/// @brief Get sign extended value
inline int64_t getSExtValue() const {
if (isSingleWord())
return int64_t(VAL << (APINT_BITS_PER_WORD - BitWidth)) >>
(APINT_BITS_PER_WORD - BitWidth);
assert(getActiveBits() <= 64 && "Too many bits for int64_t");
return int64_t(pVal[0]);
}
/// This method determines how many bits are required to hold the APInt
/// equivalent of the string given by \p str of length \p slen.
/// @brief Get bits required for string value.
static uint32_t getBitsNeeded(const char* str, uint32_t slen, uint8_t radix);
/// countLeadingZeros - This function is an APInt version of the
/// countLeadingZeros_{32,64} functions in MathExtras.h. It counts the number
/// of zeros from the most significant bit to the first one bit.
/// @returns getNumWords() * APINT_BITS_PER_WORD if the value is zero.
/// @returns the number of zeros from the most significant bit to the first
/// one bits.
/// @brief Count the number of leading one bits.
uint32_t countLeadingZeros() const;
/// countLeadingOnes - This function counts the number of contiguous 1 bits
/// in the high order bits. The count stops when the first 0 bit is reached.
/// @returns 0 if the high order bit is not set
/// @returns the number of 1 bits from the most significant to the least
/// @brief Count the number of leading one bits.
uint32_t countLeadingOnes() const;
/// countTrailingZeros - This function is an APInt version of the
/// countTrailingZoers_{32,64} functions in MathExtras.h. It counts
/// the number of zeros from the least significant bit to the first one bit.
/// @returns getNumWords() * APINT_BITS_PER_WORD if the value is zero.
/// @returns the number of zeros from the least significant bit to the first
/// one bit.
/// @brief Count the number of trailing zero bits.
uint32_t countTrailingZeros() const;
/// countPopulation - This function is an APInt version of the
/// countPopulation_{32,64} functions in MathExtras.h. It counts the number
/// of 1 bits in the APInt value.
/// @returns 0 if the value is zero.
/// @returns the number of set bits.
/// @brief Count the number of bits set.
uint32_t countPopulation() const;
/// @}
/// @name Conversion Functions
/// @{
/// This is used internally to convert an APInt to a string.
/// @brief Converts an APInt to a std::string
std::string toString(uint8_t radix, bool wantSigned) const;
/// Considers the APInt to be unsigned and converts it into a string in the
/// radix given. The radix can be 2, 8, 10 or 16.
/// @returns a character interpretation of the APInt
/// @brief Convert unsigned APInt to string representation.
inline std::string toString(uint8_t radix = 10) const {
return toString(radix, false);
}
/// Considers the APInt to be unsigned and converts it into a string in the
/// radix given. The radix can be 2, 8, 10 or 16.
/// @returns a character interpretation of the APInt
/// @brief Convert unsigned APInt to string representation.
inline std::string toStringSigned(uint8_t radix = 10) const {
return toString(radix, true);
}
/// @returns a byte-swapped representation of this APInt Value.
APInt byteSwap() 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);
}
/// 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.
/// @brief Converts APInt bits to a double
double bitsToDouble() const {
union {
uint64_t I;
double D;
} T;
T.I = (isSingleWord() ? VAL : pVal[0]);
return T.D;
}
/// 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.
/// @brief Converts APInt bits to a double
float bitsToFloat() const {
union {
uint32_t I;
float F;
} T;
T.I = uint32_t((isSingleWord() ? VAL : pVal[0]));
return T.F;
}
/// The conversion does not do a translation from double to integer, it just
/// re-interprets the bits of the double. Note that it is valid to do this on
/// any bit width but bits from V may get truncated.
/// @brief Converts a double to APInt bits.
APInt& doubleToBits(double V) {
union {
uint64_t I;
double D;
} T;
T.D = V;
if (isSingleWord())
VAL = T.I;
else
pVal[0] = T.I;
return clearUnusedBits();
}
/// The conversion does not do a translation from float to integer, it just
/// re-interprets the bits of the float. Note that it is valid to do this on
/// any bit width but bits from V may get truncated.
/// @brief Converts a float to APInt bits.
APInt& floatToBits(float V) {
union {
uint32_t I;
float F;
} T;
T.F = V;
if (isSingleWord())
VAL = T.I;
else
pVal[0] = T.I;
return clearUnusedBits();
}
/// @}
/// @name Mathematics Operations
/// @{
/// @returns the floor log base 2 of this APInt.
inline uint32_t logBase2() const {
return BitWidth - 1 - countLeadingZeros();
}
/// @brief Compute the square root
APInt sqrt() const;
/// If *this is < 0 then return -(*this), otherwise *this;
/// @brief Get the absolute value;
APInt abs() const {
if (isNegative())
return -(*this);
return *this;
}
/// @}
};
inline bool operator==(uint64_t V1, const APInt& V2) {
return V2 == V1;
}
inline bool operator!=(uint64_t V1, const APInt& V2) {
return V2 != V1;
}
namespace APIntOps {
/// @brief Determine the smaller of two APInts considered to be signed.
inline 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 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 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 APInt umax(const APInt &A, const APInt &B) {
return A.ugt(B) ? A : B;
}
/// @brief Check if the specified APInt has a N-bits integer value.
inline bool isIntN(uint32_t N, const APInt& APIVal) {
return APIVal.isIntN(N);
}
/// @returns true if the argument APInt value is a sequence of ones
/// starting at the least significant bit with the remainder zero.
inline const bool isMask(uint32_t numBits, const APInt& APIVal) {
return APIVal.getBoolValue() && ((APIVal + APInt(numBits,1)) & APIVal) == 0;
}
/// @returns true if the argument APInt value contains a sequence of ones
/// with the remainder zero.
inline const bool isShiftedMask(uint32_t numBits, const APInt& APIVal) {
return isMask(numBits, (APIVal - APInt(numBits,1)) | APIVal);
}
/// @returns a byte-swapped representation of the specified APInt Value.
inline APInt byteSwap(const APInt& APIVal) {
return APIVal.byteSwap();
}
/// @returns the floor log base 2 of the specified APInt value.
inline uint32_t logBase2(const APInt& APIVal) {
return APIVal.logBase2();
}
/// GreatestCommonDivisor - This function returns the greatest common
/// divisor of the two APInt values using Enclid's algorithm.
/// @returns the greatest common divisor of Val1 and Val2
/// @brief Compute GCD of two APInt values.
APInt GreatestCommonDivisor(const APInt& Val1, const APInt& Val2);
/// Treats the APInt as an unsigned value for conversion purposes.
/// @brief Converts the given APInt to a double value.
inline double RoundAPIntToDouble(const APInt& APIVal) {
return APIVal.roundToDouble();
}
/// Treats the APInt as a signed value for conversion purposes.
/// @brief Converts the given APInt to a double value.
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));
}
/// Treast the APInt as a signed value for conversion purposes.
/// @brief Converts the given APInt to a float value.
inline float RoundSignedAPIntToFloat(const APInt& APIVal) {
return float(APIVal.signedRoundToDouble());
}
/// RoundDoubleToAPInt - This function convert a double value to an APInt value.
/// @brief Converts the given double value into a APInt.
APInt RoundDoubleToAPInt(double Double, uint32_t width);
/// RoundFloatToAPInt - Converts a float value into an APInt value.
/// @brief Converts a float value into a APInt.
inline APInt RoundFloatToAPInt(float Float, uint32_t width) {
return RoundDoubleToAPInt(double(Float), width);
}
/// Arithmetic right-shift the APInt by shiftAmt.
/// @brief Arithmetic right-shift function.
inline APInt ashr(const APInt& LHS, uint32_t shiftAmt) {
return LHS.ashr(shiftAmt);
}
/// Logical right-shift the APInt by shiftAmt.
/// @brief Logical right-shift function.
inline APInt lshr(const APInt& LHS, uint32_t shiftAmt) {
return LHS.lshr(shiftAmt);
}
/// Left-shift the APInt by shiftAmt.
/// @brief Left-shift function.
inline APInt shl(const APInt& LHS, uint32_t shiftAmt) {
return LHS.shl(shiftAmt);
}
/// Signed divide APInt LHS by APInt RHS.
/// @brief Signed division function for APInt.
inline APInt sdiv(const APInt& LHS, const APInt& RHS) {
return LHS.sdiv(RHS);
}
/// Unsigned divide APInt LHS by APInt RHS.
/// @brief Unsigned division function for APInt.
inline APInt udiv(const APInt& LHS, const APInt& RHS) {
return LHS.udiv(RHS);
}
/// Signed remainder operation on APInt.
/// @brief Function for signed remainder operation.
inline APInt srem(const APInt& LHS, const APInt& RHS) {
return LHS.srem(RHS);
}
/// Unsigned remainder operation on APInt.
/// @brief Function for unsigned remainder operation.
inline APInt urem(const APInt& LHS, const APInt& RHS) {
return LHS.urem(RHS);
}
/// Performs multiplication on APInt values.
/// @brief Function for multiplication operation.
inline APInt mul(const APInt& LHS, const APInt& RHS) {
return LHS * RHS;
}
/// Performs addition on APInt values.
/// @brief Function for addition operation.
inline APInt add(const APInt& LHS, const APInt& RHS) {
return LHS + RHS;
}
/// Performs subtraction on APInt values.
/// @brief Function for subtraction operation.
inline APInt sub(const APInt& LHS, const APInt& RHS) {
return LHS - RHS;
}
/// Performs bitwise AND operation on APInt LHS and
/// APInt RHS.
/// @brief Bitwise AND function for APInt.
inline APInt And(const APInt& LHS, const APInt& RHS) {
return LHS & RHS;
}
/// Performs bitwise OR operation on APInt LHS and APInt RHS.
/// @brief Bitwise OR function for APInt.
inline APInt Or(const APInt& LHS, const APInt& RHS) {
return LHS | RHS;
}
/// Performs bitwise XOR operation on APInt.
/// @brief Bitwise XOR function for APInt.
inline APInt Xor(const APInt& LHS, const APInt& RHS) {
return LHS ^ RHS;
}
/// Performs a bitwise complement operation on APInt.
/// @brief Bitwise complement function.
inline APInt Not(const APInt& APIVal) {
return ~APIVal;
}
} // End of APIntOps namespace
} // End of llvm namespace
#endif