lib/Analysis/ValueTracking.cpp

1278         APInt LowBits = RA - 1;
1283         KnownZero = KnownZero2 & LowBits;
1284         KnownOne = KnownOne2 & LowBits;
1288         if (KnownZero2[BitWidth-1] || ((KnownZero2 & LowBits) == LowBits))
1289           KnownZero |= ~LowBits;
1293         if (KnownOne2[BitWidth-1] && ((KnownOne2 & LowBits) != 0))
1294           KnownOne |= ~LowBits;
1316         APInt LowBits = (RA - 1);
1319         KnownZero |= ~LowBits;
1320         KnownOne &= LowBits;
1492         unsigned LowBits = Log2_32(BitWidth)+1;
1495           LowBits -= 1;
1496         KnownZero |= APInt::getHighBitsSet(BitWidth, BitWidth - LowBits);