摘要:
Some example embodiments include an apparatus for comparing a first operand to a second operand. The apparatus includes a SIMD accelerator configured to compare first multiple parts (e.g., bytes) of first operand to second multiple parts (e.g., bytes) of the second operand. The SIMD accelerator includes a ones' complement subtraction logic and a twos' complement logic configured to perform logic operations on the multiple parts of the first operand and the multiple parts of the second operand to generate a group of carry out and propagate data across bits of the multiple parts. At least a portion of the group of carry out and propagate data is reused in the group of logic operations.
摘要:
A combined adder and logic unit having a reduced operation delay of arithmetic and logic operations, and providing an improved fan in and reduced wiring delays and capacity if implemented in the arithmetic and logic section of a microprocessor chip. The unit comprises a carry network (30) connected to operand inputs for generating carry-out signals of the byte positions (By0-By7) and further comprises a pre-sum logic (32) having a bit function generator (42) and a sum generator (45, 46, 48). Said bit function generator derives from the operands Ai and Bi bit functions Gi, Pi which are provided as logic function output and as input to said sum generator for producing preliminary arithmetic functions (SUM0, SUM1) to anticipate carry-in signals of one or zero. A result selector (70) is controlled by a byte position carry-out signal (Cy55) from the carry network means and by operation control signals to select from the output of said pre-sum logic one of the arithmetic functions (SUM0, SUM1) or one of the logic functions as result of the unit operation.
摘要:
A method, circuit apparatus, and a design structure on which the circuit resides, is provided to perform a subtraction of two operands in a binary arithmetic unit by subdividing two operands into groups of equal numbers of bits, generating, by appropriate arithmetic operations, pairs of intermediate results for the particular groups of bits of the two operands comprising the same bit positions, respectively. A first intermediate result of each pair of intermediate results is generated under the assumption of a carry-in of ‘0’ and a second intermediate result of each pair of intermediate results is generated under the assumption of a carry-in of ‘1’. The correct intermediate result of each particular pair of intermediate results from each group of bits is selected, and the result of the subtraction of the two operands is generated by an appropriate merging of the selected correct intermediate results.
摘要:
A combined binary/decimal adder unit reduces the operation delay ine processing binary coded decimal operands and permit an increased cycle rate of a processor unit in which the combined binary/decimal adder unit is utilized. Pre-sums are generated for each decimal digit position in parallel to the generation and distribution of the carries over the total of decimal digit positions of the adder unit. The pre-sums anticipate the carry-in of the decimal positions and the need to perform six corrections after the carry-out signal of the highest decimal digit position has been generated. The carry-out signal of each decimal digit position is used in combination with operation control signals to select the correct pre-sum of the digit position.
摘要:
A method to generate a magnitude result of a mathematic operation of two decimal operands within one cycle in a decimal arithmetic logic unit structure, wherein the decimal operands are in hexadecimal sign magnitude format.
摘要:
A method to generate a magnitude result of a mathematic operation of two decimal operands within one cycle in a decimal arithmetic logic unit structure, wherein the decimal operands are in hexadecimal sign magnitude format.
摘要:
A method and apparatus is provided to perform a subtraction of two operands in a binary arithmetic unit by subdividing two operands into groups of equal numbers of bits, generating, by appropriate arithmetic operations, pairs of intermediate results for the particular groups of bits of the two operands comprising the same bit positions, respectively. A first intermediate result of each pair of intermediate results is generated under the assumption of a carry-in of ‘0’ and a second intermediate result of each pair of intermediate results is generated under the assumption of a carry-in of ‘1’. The correct intermediate result of each particular pair of intermediate results from each group of bits is selected, and the result of the subtraction of the two operands is generated by an appropriate merging of the selected correct intermediate results.
摘要:
A method implemented as a computer program product for comparing two designs of electronic circuits, wherein the design representations comprise several hierarchically related sheets. The method comprises the steps of (a) identifying corresponding top-sheets of the first hierarchy level in the design versions; (b) generating a list of all sub-sheets for each top-sheet and comparing the lists to identify added, removed and common sheets of the corresponding top-sheets; (c) defining the common sheets as corresponding top-sheets of a next hierarchy level; and (d) repeating steps (a)-(c) until at least one of the top-sheets does not comprise any sub-sheet.
摘要:
A method for comparing two designs of electronic circuits, especially for comparing different versions of a design for an electronic circuit, wherein the design representations comprise several hierarchically related sheets.The method comprises the steps of:a) analyzing the hierarchies of said design versions to identify added, removed and common sheets;b) determining differences between common sheets to identify modified sheets; andc) visualizing the combined hierarchies of said design versions wherein added, removed and modified sheets are marked.
摘要:
A computerized method, data processing system and computer program product reduce noise for a buffered design of an electronic circuit which was already placed and routed. For all areas between a power stripe and a ground stripe (half bay) in the design, the shapes are divided in different criticality levels. The shapes are rearranged based on their criticality level such that shapes with higher criticality level are placed closer to the stripes than those with lower criticality level.