摘要:
To provide hardware protection against timing based side channel attacks, a processor's microarchitecture enables an OS to determine which applications have the privilege to read timestamp and performance counters. Using a white list of applications, and an authentication mechanism to authenticate applications, a legitimate Protection Required Application (PRA) may temporarily prevent other applications from reading timestamp and performance counters while it executes (or excutes sensitive operations).
摘要:
Method, apparatus, and program means for performing bitstream buffer manipulation with a SIMD merge instruction. The method of one embodiment comprises determining whether any unprocessed data bits for a partial variable length symbol exist in a first data block is made. A shift merge operation is performed to merge the unprocessed data bits from the first data block with a second data block. A merged data block is formed. A merged variable length symbol comprised of the unprocessed data bits and a plurality of data bits from the second data block is extracted from the merged data block.
摘要:
To provide hardware protection against timing based side channel attacks, a processor's microarchitecture enables an OS to determine which applications have the privilege to read timestamp and performance counters. Using a white list of applications, and an authentication mechanism to authenticate applications, a legitimate Protection Required Application (PRA) may temporarily prevent other applications from reading timestamp and performance counters while it executes (or excutes sensitive operations).
摘要:
A method and apparatus for including in a processor instructions for performing horizontal intra-add operations on packed data. One embodiment of the processor is coupled to a memory. The memory has stored therein at least a first packed data. The processor performs operations on data elements in the first packed data to generate a plurality of data elements in a second packed data in response to receiving an instruction. At least two of the plurality of data elements in the second packed data store the results of an intra-add operation, at least one of these results coming from the operation on data elements of the first packed data. One embodiment of a software method utilizes horizontal intra-add instructions for performing butterfly computations as may be employed, for example, in Walsh-Hadamard transforms or in Fast-Fourier Transforms.
摘要:
A method for a parallel shift right merge of data. The method of one embodiment comprises receiving a shift count of M. A first operand having a first set of L data elements is shifted left by ‘L−M’ data elements. A second operand having a second set of L data elements is shifted right by M data elements. The shifted first set is merged with the shifted second set to generate a resultant having L data elements.
摘要:
A processor is described that includes a plurality of execution units in a processor core. The processor also may include power management circuitry to determine a configuration with a lowest power cost from a plurality of configurations that each have a different number of enabled execution units for a same active performance state. A method may include determining with power management circuitry of a processor a configuration with a lowest power cost from a plurality of configurations that each have a different number of enabled execution units in a processor core of the processor for a same active performance state.
摘要:
Method, apparatus, and program means for performing bitstream buffer manipulation with a SIMD merge instruction. The method of one embodiment comprises determining whether any unprocessed data bits for a partial variable length symbol exist in a first data block is made. A shift merge operation is performed to merge the unprocessed data bits from the first data block with a second data block. A merged data block is formed. A merged variable length symbol comprised of the unprocessed data bits and a plurality of data bits from the second data block is extracted from the merged data block.
摘要:
Method, apparatus, and program means for performing bitstream buffer manipulation with a SIMD merge instruction. The method of one embodiment comprises determining whether any unprocessed data bits for a partial variable length symbol exist in a first data block is made. A shift merge operation is performed to merge the unprocessed data bits from the first data block with a second data block. A merged data block is formed. A merged variable length symbol comprised of the unprocessed data bits and a plurality of data bits from the second data block is extracted from the merged data block.
摘要:
Method, apparatus, and program means for performing bitstream buffer manipulation with a SIMD merge instruction. The method of one embodiment comprises determining whether any unprocessed data bits for a partial variable length symbol exist in a first data block is made. A shift merge operation is performed to merge the unprocessed data bits from the first data block with a second data block. A merged data block is formed. A merged variable length symbol comprised of the unprocessed data bits and a plurality of data bits from the second data block is extracted from the merged data block.
摘要:
Method, apparatus, and program means for performing bitstream buffer manipulation with a SIMD merge instruction. The method of one embodiment comprises determining whether any unprocessed data bits for a partial variable length symbol exist in a first data block is made. A shift merge operation is performed to merge the unprocessed data bits from the first data block with a second data block. A merged data block is formed. A merged variable length symbol comprised of the unprocessed data bits and a plurality of data bits from the second data block is extracted from the merged data block.