llvm/ADT/APInt.h

68 ///   * In general, the class tries to follow the style of computation that LLVM
70 ///   * APInt supports zero-bit-width values, but operations that require bits
72 ///     integer).  This means that operations like zero extension and logical
121   /// Note that bigVal.size() can be smaller or larger than the corresponding
140   /// interpretation stops when the first character that is not suitable for the
150   /// Default constructor that creates an APInt with a 1-bit zero value.
154   APInt(const APInt &that) : BitWidth(that.BitWidth) {
156       U.VAL = that.U.VAL;
158       initSlowCase(that);
162   APInt(APInt &&that) : BitWidth(that.BitWidth) {
163     memcpy(&U, &that.U, sizeof(U));
164     that.BitWidth = 0;
225   /// Constructs an APInt value that has a contiguous range of bits set. The
255   /// Constructs an APInt value that has a contiguous range of bits set. The
270   /// Constructs an APInt value that has the top hiBitsSet bits set.
280   /// Constructs an APInt value that has the bottom loBitsSet bits set.
331   /// that 0 is not a positive value.
530   /// one of them (if needed!) to ensure that the bit-widths match.
610   APInt &operator=(APInt &&that) {
613     if (this == &that)
616     assert(this != &that && "Self-move not supported");
620     // Use memcpy so that type based alias analysis sees both VAL and pVal
622     memcpy(&U, &that.U, sizeof(U));
624     BitWidth = that.BitWidth;
625     that.BitWidth = 0;
965   /// Note that this is a true remainder operation and not a modulo operation
987   // Operations that return overflow indicators.
1000   // Operations that saturate
1220   /// between this APInt and RHS that are both set.
1228   /// This operation checks that all bits set in this APInt are also set in RHS.
1243   /// that is greater than the current width.
1263   /// It is an error to specify a width that is less than the
1270   /// are filled with 0 bits.  It is an error to specify a width that is less
1277   /// extended, truncated, or left alone to make it that width.
1283   /// extended, truncated, or left alone to make it that width.
1437   /// Here one word's bitwidth equals to that of uint64_t.
1444   /// *NOTE* Here one word's bitwidth equals to that of uint64_t.
1473   /// returns the smallest bit width that will retain the negative value. For
1530   /// Get the bits that are sufficient to represent the string value. This may
1570   /// Computes the number of leading bits of this APInt that are equal to its
1662   /// re-interprets the bits as a double. Note that it is valid to do this on
1669   /// re-interprets the bits as a float. Note that it is valid to do this on
1728   /// *this.  Note that the "most negative" signed number (e.g. -128 for 8 bit
1763   /// DST, of dstCOUNT parts, such that the bit srcLSB becomes the least
1853   /// Used to insert APInt objects, or objects that contain APInt objects, into
1906   /// word that are not used by the APInt. This is needed after the most
1907   /// significant word is assigned a value to ensure that those bits are
1943   /// This is used by the constructors that take string arguments.
1946   /// not assume that the string is well-formed and (2) grows the
1967   void initSlowCase(const APInt &that);
2040 /// \returns an APInt that is the bitwise complement of \p v.
2244 /// This function finds the smallest number n, such that
2258 /// value to go from [-2^BW, 0) to [0, 2^BW). In that sense, zero is
2261 /// This function returns std::nullopt if after finding k that minimizes the
2279 /// most significant bit that is different in the values.