VERIFICATION SUPPORT APPARATUS, VERIFICATION SUPPORT METHOD, AND COMPUTER PRODUCT

• US 20090282377A1
• Filed: 01/21/2009
• Published: 11/12/2009
• Est. Priority Date: 05/09/2008
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Tamiya, Yutaka
• Granted Patent: US 8,065,643 B2
• Time in Patent Office: Days
• US Class Current: 716/113
• CPC Class Codes: G06F 2119/12 Timing analysis or timing optimisation
• CPC Class Codes: G06F 30/3312 Timing analysis

Abstract

An effective data amount and a power index of a module selected from a design target circuit are extracted from a time-series table DB for each clock cycle. Time periods during which the effective data amount is “0” and there is a high possibility of improving power consumption, are identified. It is determined whether a first simulation result from the design target circuit and a second simulation result from the design target circuit into which a control circuit has been inserted to stop the supply of a clock to the module continuously for the identified time periods coincide. Then, if the first and the second simulation results coincide, the time periods are determined as targets to which clock gating is applicable.

Claims

1. A computer-readable recording medium storing therein a design support program that causes a computer to execute:

selecting arbitrarily a module from a design target circuit;

extracting, by accessing a table, a data amount and a power index corresponding to the module selected at the selecting, the table storing therein time-series data amounts for data signals transmitted from modules in the design target circuit and received by recipient modules, and power indexes indicative of a potential of improving power consumption in the modules according to data amount;

detecting from among time periods during which a recipient module does not receive a data signal, time periods during which the power index meets a criterion for improving power consumption, the detecting being based on the data amount and the power index extracted at the extracting; and

outputting the time periods detected at the detecting.

2. The computer-readable recording medium according to claim 1, wherein the design support program further causes the computer to execute

comparing results of simulations in which an identical data signal is supplied to the design target circuit and to a circuit identical to the design target circuit and further including a control circuit that stops, continuously for the time periods detected at the detecting, a supply of a clock to the module selected at the selecting, and

the outputting includes outputting a comparison result obtained at the comparing.

3. The computer-readable recording medium according to claim 2, wherein the design support program further causes the computer to execute

inserting the control circuit into the design target circuit, based on the comparison result obtained at the comparing, and

the outputting includes outputting the design target circuit that includes the control circuit inserted at the inserting.

4. The computer-readable recording medium according to claim 3, wherein the design support program further causes the computer to execute

determining, based on the comparison result obtained at the comparing, whether values of a data signal coincide between the design target circuit and the circuit, and

the outputting includes outputting a determination result obtained at the determining.

5. The computer-readable recording medium according to claim 4, wherein

the inserting includes inserting the control circuit into the design target circuit when at the determining, the values of the data signal are determined to coincide.

6. The computer-readable recording medium according to claim 4, wherein

the determining includes determining whether values of a data signal transmitted from the module selected at the selecting coincide between the design target circuit and the circuit.

7. The computer-readable recording medium according to claim 4, wherein

the determining includes determining whether a value of a data signal output from the design target circuit coincides with a value of the data signal output from the circuit.

8. The computer-readable recording medium according to claim 4, wherein

the determining includes determining whether a value of a data signal output from the design target circuit and a value of a data signal output from an arbitrary circuit element in the design target circuit respectively coincide in the design target circuit and in the circuit.

9. The computer-readable recording medium according to claim 3, wherein

the table further stores therein a time-series estimated value of power consumption for each of the modules,

the extracting further includes accessing the table and extracting values of power consumption for the module selected by the selecting unit,

the design support program further causes the computer to execute calculating a value of power consumption improved by insertion of the control circuit into the design target circuit, the calculating including cumulating, based on the values of power consumption extracted at the extracting, the values of power consumption in the module for the time periods detected at the detecting, and

the outputting further includes outputting the value of power consumption calculated at the calculating.

10. The computer-readable recording medium according to claim 9, wherein the design support program further causes the computer to execute

judging whether the value of power consumption calculated at the calculating is less than a threshold,

the selecting further includes selecting, from the design target circuit, a module that has not been selected, when at the judging the value is judged to be less than the threshold.

11. The computer-readable recording medium according to claim 10, wherein

the selecting further includes accessing the table and selecting, from the design target circuit, a module having at least a given value of power consumption.

12. The computer-readable recording medium according to claim 11, wherein

the selecting further includes selecting, from the design target circuit, a module having the highest value of power consumption.

13. The computer-readable recording medium according to claim 1, wherein

the detecting further includes detecting, from among time periods during which the recipient module does not receive the data signal, time periods during which the power index is equal to or more than a threshold.

14. A design support apparatus comprising:

a selecting unit that arbitrarily selects a module from a design target circuit;

an extracting unit that accesses a table and extracts a data amount and a power index corresponding to the module selected by the selecting unit, the table storing therein time-series data amounts for data signals transmitted from modules in the design target circuit and received by recipient modules, and power indexes indicative of a potential of improving power consumption in the modules according to data amount;

a detecting unit that, based on the data amount and the power index extracted by the extracting unit, detects from among time periods during which a recipient module does not receive a data signal, time periods during which the power index meets a criterion for improving power consumption; and

an output unit that outputs the time periods detected by the detecting unit.

15. A design support method comprising:

selecting arbitrarily a module from a design target circuit;

extracting, by accessing a table, a data amount and a power index corresponding to the module selected at the selecting, the table storing therein time-series data amounts for data signals transmitted from modules in the design target circuit and received by recipient modules, and power indexes indicative of a potential of improving power consumption in the modules according to data amount;

detecting from among time periods during which a recipient module does not receive a data signal, time periods during which the power index meets a criterion for improving power consumption, the detecting being based on the data amount and the power index extracted at the extracting; and

outputting the time periods detected at the detecting.