摘要:
The present invention relates to the design of highly reliable high performance microprocessors, and more specifically to designs using a blind invalidate circuit in high-speed memories. In accordance with an embodiment of the present invention, a tag array memory circuit including a plurality of memory bit circuits coupled together to form an n-bit memory cell; and a blind invalidate circuit coupled to a memory bit circuit in the n-bit memory cell, the blind invalidate circuit to clear a bit in the memory bit circuit, if a primary clear bit line is asserted and a received bit value of a right-adjacent memory bit circuit is zero.
摘要:
The present invention relates to the design of highly reliable high performance microprocessors, and more specifically to designs that use cache memory protection schemes such as, for example, a 1-hot plus valid bit scheme and a 2-hot vector cache scheme. These protection schemes protect the 1-hot vectors used in the tag array in the cache and are designed to provide hardware savings, operate at higher speeds and be simple to implement. In accordance with an embodiment of the present invention, a tag array memory circuit includes a plurality of memory bit circuits coupled together to form an n-bit memory cell, and a valid bit circuit coupled to the n-bit memory cell, the valid bit circuit being configured to be accessed simultaneously with the plurality of memory bit circuits.
摘要:
The present invention relates to the design of highly reliable high performance microprocessors, and more specifically to designs that use cache memory protection schemes such as, for example, a 1-hot plus valid bit scheme and a 2-hot vector cache scheme. These protection schemes protect the 1-hot vectors used in the tag array in the cache and are designed to provide hardware savings, operate at higher speeds and be simple to implement. In accordance with an embodiment of the present invention, a tag array memory including an input conversion circuit to receive a 1-hot vector and to convert the 1-hot vector to a 2-hot vector. The tag array memory also including a memory array coupled to the input conversion circuit, the memory array to store the 2-hot vector; and an output conversion circuit coupled to the memory array, the output conversion circuit to receive the 2-hot vector and to convert the 2-hot vector back to the 1-hot vector.
摘要:
The present invention relates to the design of highly reliable high performance microprocessors, and more specifically to designs that use cache memory protection schemes such as, for example, a 1-hot plus valid bit scheme and a 2-hot vector cache scheme. These protection schemes protect the 1-hot vectors used in the tag array in the cache and are designed to provide hardware savings, operate at higher speeds and be simple to implement. In accordance with an embodiment of the present invention, a tag array memory including an input conversion circuit to receive a 1-hot vector and to convert the 1-hot vector to a 2-hot vector. The tag array memory also including a memory array coupled to the input conversion circuit, the memory array to store the 2-hot vector; and an output conversion circuit coupled to the memory array, the output conversion circuit to receive the 2-hot vector and to convert the 2-hot vector back to the 1-hot vector.
摘要:
The present invention relates to the design of highly reliable high performance microprocessors, and more specifically to designs that use cache memory protection schemes such as, for example, a 1-hot plus valid bit scheme and a 2-hot vector cache scheme. These protection schemes protect the 1-hot vectors used in the tag array in the cache and are designed to provide hardware savings, operate at higher speeds and be simple to implement. In accordance with an embodiment of the present invention, a tag array memory circuit includes a plurality of memory bit circuits coupled together to form an n-bit memory cell, and a valid bit circuit coupled to the n-bit memory cell, the valid bit circuit being configured to be accessed simultaneously with the plurality of memory bit circuits.
摘要:
The present invention relates to the design of highly reliable high performance microprocessors, and more specifically to designs that use cache memory protection schemes such as, for example, a 1-hot plus valid bit scheme and a 2-hot vector cache scheme. These protection schemes protect the 1-hot vectors used in the tag array in the cache and are designed to provide hardware savings, operate at higher speeds and be simple to implement. In accordance with an embodiment of the present invention, a tag array memory including an input conversion circuit to receive a 1-hot vector and to convert the 1-hot vector to a 2-hot vector. The tag array memory also including a memory array coupled to the input conversion circuit, the memory array to store the 2-hot vector; and an output conversion circuit coupled to the memory array, the output conversion circuit to receive the 2-hot vector and to convert the 2-hot vector back to the 1-hot vector.
摘要:
A system and method of accounting for lost clock cycles in a microprocessor. A method includes detecting a first reason which prevents exit of an entry from an instruction retirement queue, and incrementing a first count corresponding to the first reason, wherein the first count is incremented while the first reason prevents exit of the entry from the queue. A first point in time is determined when said first reason no longer prevents exit of the entry from the queue. A second reason which prevents exit of the entry from the queue is detected, wherein the second reason came into existence prior to said first point in time. A second count corresponding to the second reason is incremented, wherein incrementing the second count begins at the first point in time.
摘要:
A processor is provided that implements a replay mechanism to recover from soft errors. The processor includes a protected execution unit, a check unit to detect errors in results generated by the protected execution unit, and a replay unit to track selected instructions issued to the protected execution unit. When the check unit detects an error, it triggers the replay unit to reissue the selected instructions to the protected execution unit. One embodiment of the replay unit provides an instruction buffer that includes pointers to track issue and retirement status of in-flight instructions. When the check unit indicates an error, the replay unit resets a pointer to reissue the instruction for which the error was detected.
摘要:
A processor core includes an instruction decode unit that may dispatch a same integer instruction stream to a plurality of integer execution units and may consecutively dispatch a same floating-point instruction stream to a floating-point unit. The integer execution units may operate in lock-step such that during each clock cycle, each respective integer execution unit executes the same integer instruction. The floating-point unit may execute the same floating-point instruction stream twice. Prior to the integer instructions retiring, compare logic may detect a mismatch between execution results from each of the integer execution units. In addition, prior to the results of the floating-point instruction stream transferring out of the floating-point unit, the compare logic may also detect a mismatch between results of execution of each consecutive floating-point instruction stream. Further, in response to detecting any mismatch, the compare logic may cause instructions causing the mismatch to be re-executed.
摘要:
A system and method of accounting for lost clock cycles in a microprocessor. A method includes detecting a first reason which prevents exit of an entry from an instruction retirement queue, and incrementing a first count corresponding to the first reason, wherein the first count is incremented while the first reason prevents exit of the entry from the queue. A first point in time is determined when said first reason no longer prevents exit of the entry from the queue. A second reason which prevents exit of the entry from the queue is detected, wherein the second reason came into existence prior to said first point in time. A second count corresponding to the second reason is incremented, wherein incrementing the second count begins at the first point in time.