Method sext

ext/src/llvm/APInt.cpp:911–932

Sign extend to a new width.

// Sign extend to a new width.
APInt APInt::sext(unsigned Width) const {
  assert(Width > BitWidth && "Invalid APInt SignExtend request");

  if (Width <= APINT_BITS_PER_WORD)
    return APInt(Width, SignExtend64(U.VAL, BitWidth));

  APInt Result(getMemory(getNumWords(Width)), Width);

  // Copy words.
  std::memcpy(Result.U.pVal, getRawData(), getNumWords() * APINT_WORD_SIZE);

  // Sign extend the last word since there may be unused bits in the input.
  Result.U.pVal[getNumWords() - 1] =
      SignExtend64(Result.U.pVal[getNumWords() - 1],
                   ((BitWidth - 1) % APINT_BITS_PER_WORD) + 1);

  // Fill with sign bits.
  std::memset(Result.U.pVal + getNumWords(), isNegative() ? -1 : 0,
              (Result.getNumWords() - getNumWords()) * APINT_WORD_SIZE);
  Result.clearUnusedBits();
  return Result;
}

//  Zero extend to a new width.
APInt APInt::zext(unsigned width) const {