Lines Matching full:bits
11 // instructions (shifts, some ands, ors, etc.) kill some of their input bits.
12 // We track these dead bits and remove instructions that compute only these
13 // dead bits.
43 STATISTIC(NumSimplified, "Number of instructions trivialized (dead bits)");
92 // compute known bits of both operands in order to determine the live bits of
121 // The alive bits of the input are the swapped alive bits of
127 // We need some output bits, so we need all bits of the
137 // We need some output bits, so we need all bits of the
150 // bits than that (adds, and thus subtracts, ripple only to the
161 // If the shift is nuw/nsw, then the high bits are not dead
177 // If the shift is exact, then the low bits are not dead
190 // high-order bits of the result, if we need any of those
191 // bits, then we must keep the highest input bit.
196 // If the shift is exact, then the low bits are not dead
205 // For bits that are known zero, the corresponding bits in the
207 // case they can't both be dead, so just mark the LHS bits as
221 // For bits that are known one, the corresponding bits in the
223 // case they can't both be dead, so just mark the LHS bits as
247 // high-order bits of the result, if we need any of those
248 // bits, then we must keep the highest input bit.
281 // bits and add the instruction to the work list. For other instructions
283 // all bits as live).
323 // Compute the set of alive bits for each operand. These are anded into the
324 // existing set, if any, and if that changes the set of alive bits, the
335 // If all bits of the output are dead, then all bits of the input
336 // Bits of each operand that are used to compute alive bits of the
343 // If we've added to the set of alive bits (or the operand has not
369 // For live instructions that have all dead bits, first make them dead by
378 DEBUG(dbgs() << "BDCE: Trivializing: " << I << " (all bits dead)\n");
