摘要:
There is provided a memory for storing data comprising: a fast data reading mechanism operable to read a data value from said memory to generate a fast read result that is output from said memory for further processing; a slow data reading mechanism operable to read said data value from said memory to generate a slow read result available after said fast read result has been output for further processing, said slow data reading mechanism being less prone to error in reading said data value than said fast data reading mechanism; a comparator operable to compare said fast read result and said slow read result to detect if said fast read result differs from said slow read result; and error repair logic operable if said comparator detects that said fast read result differs from said slow read result to suppress said further processing using said fast read result, to output said slow read result in place of said fast read result and to restart said further processing based upon said slow read result.
摘要:
A performance counter accumulates a value by periodically adding a variable increment value representing the amount of work performed. The increment value can be varied in dependence upon the processor clock frequency and may be adjusted under hardware and/or software control.
摘要:
A memory circuit for use in a data processing circuit is described, in which memory cells have at least two states, each state being determined by both a first voltage level corresponding to a first supply line and a second voltage level corresponding to a second supply line. The memory circuit comprises a readable state in which information stored in a memory cell is readable and an unreadable state in which information stored in said memory cell is reliably retained but unreadable. Changing the first voltage level but keeping the second voltage level substantially constant effects a transition between the readable state and the unreadable state. In use, the static power consumption of the memory cell in the unreadable state is less than static power consumption of the memory cell in the readable state.
摘要:
Performance level selection is carried out by calculating a plurality of performance requests using a plurality of performance request calculating algorithms, combining those different performance requests to form a global performance request and then selecting a performance level in dependence upon the global performance level request. The performance request calculating algorithms can be arranged in a hierarchy with their performance requests evaluated in a sequence starting from the least dominant position in the hierarchy and moving through to the most dominant position in the hierarchy. Commands may accompany each performance level request to specify how it should be combined with other performance level requests.
摘要:
An integrated circuit includes a plurality of processing stages each including processing logic 1014, a non-delayed signal-capture element 1016, a delayed signal-capture element 1018 and a comparator 1024. The non-delayed signal-capture element 1016 captures an output from the processing logic 1014 at a non-delayed capture time. At a later delayed capture time, the delayed signal-capture element 1018 also captures a value from the processing logic 1014. An error detection circuit 1026 and error correction circuit 1028 detect and correct random errors in the delayed value and supplies an error-checked delayed value to the comparator 1024. The comparator 1024 compares the error-checked delayed value and the non-delayed value and if they are not equal this indicates that the non-delayed value was captured too soon and should be replaced by the error-checked delayed value. The non-delayed value is passed to the subsequent processing stage immediately following its capture and accordingly error recovery mechanisms are used to suppress the erroneous processing which has occurred by the subsequent processing stages, such as gating the clock and allowing the correct signal values to propagate through the subsequent processing logic before restarting the clock. The operating parameters of the integrated circuit, such as the clock frequency, the operating voltage, the body biased voltage, temperature and the like are adjusted so as to maintain a finite non-zero error rate in a manner that increases overall performance.
摘要:
An integrated circuit includes a plurality of processing stages each including processing logic 2, a non-delayed latch 4, a delayed latch 8 and a comparator 6. The non-delayed latch 4 captures an output from the processing logic 2 at a non-delayed capture time. At a later delayed capture time, the delayed latch 8 also captures a value from the processing logic 2. The comparator 6 compares these values and if they are not equal this indicates that the non-delayed value was captured too soon and should be replaced by the delayed value. The non-delayed value is passed to the subsequent processing stage immediately following its capture and accordingly error recovery mechanisms are used to suppress the erroneous processing which has occurred by the subsequent processing stages, such as gating the clock and allowing the correct signal values to propagate through the subsequent processing logic before restarting the clock. The operating parameters of the integrated circuit, such as the clock frequency, the operating voltage, the body biased voltage, temperature and the like are adjusted so as to maintain a finite non-zero error rate in a manner that increases overall performance.
摘要:
A memory circuit for use in a data processing circuit is described, in which memory cells have at least two states, each state being determined by both a first voltage level corresponding to a first supply line and a second voltage level corresponding to a second supply line. The memory circuit comprises a readable state in which information stored in a memory cell is readable and an unreadable state in which information stored in said memory cell is reliably retained but unreadable. Changing the first voltage level but keeping the second voltage level substantially constant effects a transition between the readable state and the unreadable state. In use, the static power consumption of the memory cell in the unreadable state is less than static power consumption of the memory cell in the readable state.
摘要:
An integrated circuit 2 has a specified range of runtime-variable operating parameters. Data processing circuits 4 within the integrated circuit 2 have associated error detection and error repair mechanisms 6. When operating within a narrow typical-case range of runtime-variable operating parameters the data processing circuits 4 operate correctly and substantially without error. When operating outside of this typical-case range but inside the specified range of permitted values for the run-time variable operating parameters, then the error detection and error repair circuit 6 operate to repair the errors which occur.
摘要:
A data processing system is provided having a processor and analysing circuitry for identifying a SIMD instruction associated with a first SIMD instruction set and replacing it by a functionally-equivalent scalar representation and marking that functionally-equivalent scalar representation. The marked functionally-equivalent scalar representation is dynamically translated using translation circuitry upon execution of the program to generate one or more corresponding translated instructions corresponding to a instruction set architecture different from the first SIMD architecture corresponding to the identified SIMD instruction.
摘要:
An integrated circuit includes a plurality of processing stages each including processing logic, a non-delayed signal-capture element, a delayed signal-capture element and a comparator. The non-delayed signal-capture element captures an output from the processing logic at a non-delayed capture time. At a later delayed capture time, the delayed signal-capture element also captures a value from the processing logic. An error detection circuit and error correction circuit detect and correct random errors in the delayed value and supplies an error-checked delayed value to the comparator. The comparator compares the error-checked delayed value and the non-delayed value and if they are not equal this indicates that the non-delayed value was captured too soon and should be replaced by the error-checked delayed value. The non-delayed value is passed to the subsequent processing stage immediately following its capture and accordingly error recovery mechanisms are used to suppress the erroneous processing which has occurred by the subsequent processing stages, such as gating the clock and allowing the correct signal values to propagate through the subsequent processing logic before restarting the clock. The operating parameters of the integrated circuit, such as the clock frequency, the operating voltage, the body biased voltage, temperature and the like are adjusted so as to maintain a finite non-zero error rate in a manner that increases overall performance.