发明申请
US20090024643A1 Multi-Level Compressed Look-up Tables Formed by Logical Operations to Compress Selected Index Bits
有权

基本信息:
- 专利标题: Multi-Level Compressed Look-up Tables Formed by Logical Operations to Compress Selected Index Bits
- 专利标题(中):通过逻辑操作形成的多级压缩查找表来压缩所选择的索引位
- 申请号:US12190692 申请日:2008-08-13
- 公开(公告)号:US20090024643A1 公开(公告)日:2009-01-22
- 发明人: Millind Mittal
- 申请人: Millind Mittal
- 申请人地址: US CA Santa Clara
- 专利权人: X-ENGINES, INC
- 当前专利权人: X-ENGINES, INC
- 当前专利权人地址: US CA Santa Clara
- 主分类号: G06F17/30
- IPC分类号: G06F17/30
摘要:
A lookup is performed using multiple levels of compressed stride tables in a multi-bit Trie structure. An input lookup key is divided into several strides including a current stride of S bits. A valid entry in a current stride table is located by compressing the S bits to form a compressed index of D bits into the current stride table. A compression function logically combines the S bits to generate the D compressed index bits. An entry in a prior-level table points to the current stride table and has a field indicating which compression function and mask to use. Compression functions can include XOR, shifts, rotates, and multi-bit averaging. Rather than store all 2S entries, the current stride table is compressed to store only 2D entries. Ideally, the number of valid entries in the current stride table is between 2D−1 and 2D for maximum compression. Storage requirements are reduced.
摘要(中):
在多位Trie结构中使用多级压缩步幅表进行查找。 输入查找键被分成包括S位的当前步幅的几个步骤。 通过压缩S位来形成当前步幅表中的有效条目,以形成D位的压缩索引到当前步幅表中。 压缩函数逻辑组合S位以产生D压缩索引位。 前一级表中的条目指向当前步幅表,并具有指示要使用的压缩函数和掩码的字段。 压缩功能可以包括XOR,移位,旋转和多位平均。 而不是存储所有2S条目,当前步幅表被压缩以仅存储2D条目。 理想情况下,当前步幅表中有效条目的数量在2D-1和2D之间用于最大压缩。 存储要求降低。
公开/授权文献:
IPC结构图谱:
G | 物理 |
--G06 | 计算;推算;计数 |
----G06F | 电数字数据处理 |
------G06F17/00 | 特别适用于特定功能的数字计算设备或数据处理设备或数据处理方法 |
--------G06F17/30 | .信息检索;及其数据库结构 |