Invention Grant
- Patent Title: Mechanism for carryless multiplication that employs booth encoding
- Patent Title (中): 采用展位编码的无刷乘法机制
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Application No.: US12960239Application Date: 2010-12-03
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Publication No.: US08667040B2Publication Date: 2014-03-04
- Inventor: Timothy A. Elliott
- Applicant: Timothy A. Elliott
- Applicant Address: TW New Taipei
- Assignee: VIA Technologies, Inc.
- Current Assignee: VIA Technologies, Inc.
- Current Assignee Address: TW New Taipei
- Agent Richard K. Huffman; James W. Huffman
- Main IPC: G06F7/00
- IPC: G06F7/00 ; G06F7/38

Abstract:
An apparatus having operand registers, an opcode detector, a carryless preformat unit, a compressor, a left shifter, and exclusive-OR logic. The operand registers receive operands for a carryless multiplication. The opcode detector receives a carryless multiplication instruction, and asserts a carryless signal. The carryless preformat unit partitions a first operand into a plurality of parts that are such that a Booth encoder is precluded from selection of second partial products of a second operand, where the second partial products reflect implicit carry operations. The compressor sums first partial products of the second operand via carry save adders arranged in a Wallace tree configuration, where generation of carry bits is disabled. The left shifter shifts one or more outputs of the compressor. The exclusive-OR logic executes an exclusive-OR function to yield a carryless multiplication result.
Public/Granted literature
- US20120143934A1 MECHANISM FOR CARRYLESS MULTIPLICATION THAT EMPLOYS BOOTH ENCODING Public/Granted day:2012-06-07
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