Method and apparatus for interruption of carry propagation on partition boundaries

A system for performing partitionable carry-lookahead logic on two N-nary operands, comprising:

• a 1-of-P first input that receives the 1-of-P first operand and a 1-of-Q second input that receives the 1-of-Q second operand, wherein each said operand comprises one or more blocks comprising one or more bits, wherein each said operand further comprises one or more partition comprising one or more said blocks;
• an arithmetic logic means, coupled to said first input and said second input, for performing an arithmetic operation on one or more groupings of one or more bits of the first operand and on one or more grouping of one or more bits of the second operand, to produce an intermediate result, said arithmetic logic means further comprises a means for performing carry propagate logic to produce an intermediate HPG indicator for each said grouping;
• and
• a partition detection means, coupled to said arithmetic logic means, for producing a 1-of-R block-level HPG indicator for each said block, wherein the value of said block-level HPG indicator does not allow carry propagation across said partition boundaries.

A method to manufacture an apparatus that performs partitionable carry-lookahead logic on two N-nary operands, comprising:

• providing a 1-of-P first input that receives the 1-of-P first operand and a 1-of-Q second input that receives the 1-of-Q second operand, wherein each said operand comprises one or more blocks comprising one or more bits, wherein each said operand further comprises one or more partition comprising one or more said blocks;
• providing an arithmetic logic that performs an arithmetic operation on one or more grouping of one or more bits of the first operand and on one or more grouping of one or more bits of the second operand, to produce an intermediate result, said arithmetic logic also performs carry propagate logic to produce an intermediate HPG indicator for each said grouping;
• coupling said arithmetic logic to said first input and to said second input;
• providing a partition detection logic that produces a 1-of-R block-level HPG indicator for each said block, wherein the value of said block-level HPG indicator does not allow carry propagation across said partition boundaries;
• and
• coupling said partition detection logic to said arithmetic logic.

A method to perform partitionable carry-lookahead logic on two N-nary operands, comprising:

• receiving the 1-of-P first operand and receiving the 1-of-Q second operand, wherein each said operand comprises one or more blocks comprising one or more bits, wherein each said operand further comprises one or more partition comprising one or more said blocks;
• performing an arithmetic operation on one or more grouping of one or more bits of the first operand and on one or more grouping of one or more bits of the second operand, to produce an intermediate result;
• performing carry propagate logic on one or more grouping of one or more bits of the first operand and on one or more grouping of one or more bits of the second operand, to produce an intermediate HPG indicator for each said grouping;
• and
• producing a 1-of-R block-level HPG indicator for each said block, wherein the value of said block-level HPG indicator does not allow carry propagation across said partition boundaries.