| 摘要 |
A data processing apparatus 2 comprises a processing circuit 4 and instruction decoder 6. A bitfield manipulation instruction controls the processing apparatus 2 to generate at least one result data element from corresponding first and second source data elements src1, src2. Each result data element includes a portion corresponding to a bitfield bf of the corresponding first source data element src1. Bits of the result data element that are more significant than the inserted bitfield bf have a prefix value p that is selected, based on a control value specified by the instruction, as one of a first prefix value having a zero value, a second prefix value having the value of a portion of the corresponding second source data element src2, and a third prefix value corresponding to a sign extension of the bitfield bf of the first source data element src1. |
