International Business Machines Corporation

Erez Barak

Osher Yifrach

Steven R Carlough

Silvia Melitta Mueller

Juergen Haess

Eyal Gonen

Giora Biran

Shiri Moran

Amir Turi

Bodo Hoppe

Eyal Naor

Eli Arbel

Cédric Lichtenau

Udo Krautz

Nicol Hofmann

Shlomit Koyfman

Martin Recktenwald

Jonathan T Hsieh

Michael J Cadigan, Jr

Aditya Nitin Puranik

Ziv Nevo

Oz Dov Hershkovitz

Yair Fried

Deepankar Bhattacharjee

Ido Rozenberg

Gilad Merran

Methods, systems and computer program products for monitoring delivered packages are provided. Aspects include receiving, by a co-processor, a data stream and performing processing on the data stream. Aspects also include writing, by the co-processor, a data record into the output buffer. Based on a determination that the data record should replace a most recently stored data record in a cache, aspects include providing, by the co-processor to the cache controller, an instruction for the cache controller to write the data record to a location in the cache obtained from a most recently used address register. Based on a determination that the data record should not replace the most recently stored data record in the cache, aspects include writing, by the cache controller, the data record to an available location in the cache.

Maintaining data order between buffers

The present disclosure provides reducing clock power consumption of a computer processor by simulating, in a baseline simulation of a computer processor design using a software model of the computer processor design, performance of an instruction by the computer processor design, to produce a baseline result of the instruction, and identifying a circuit of the computer processor design that receives a clock signal during performance of the instruction, and in a comparison simulation of the computer processor design using the software model of the computer processor design, simulating performance of the instruction by the computer processor design while injecting a corruption signal into the circuit, to produce a comparison result of the instruction, and designating the circuit for clock gating when processing the instruction, if the comparison result of the instruction is identical to the baseline result of the instruction.

Reducing clock power consumption of a computer processor

Examples of techniques for modifying testing tools are described herein. An example computer-implemented method includes receiving, via a processor, a netlist comprising a complex coverage event that depends on a singular independent signal. The method includes detecting, via the processor, that complex coverage event can be separated into the singular independent signal and a logic state based on a structural logic analysis. The method also includes modifying, via the processor, a testing tool to test the netlist based on the singular independent signal.

Testing netlists based on singular independent signals

Reducing clock power consumption of a computer processor by simulating, in a baseline simulation of a computer processor design using a software model of the computer processor design, performance of an instruction by the computer processor design, to produce a baseline result of the instruction, and identifying a circuit of the computer processor design that receives a clock signal during performance of the instruction, and in a comparison simulation of the computer processor design using the software model of the computer processor design, simulating performance of the instruction by the computer processor design while injecting a corruption signal into the circuit, to produce a comparison result of the instruction, and designating the circuit for clock gating when processing the instruction, if the comparison result of the instruction is identical to the baseline result of the instruction.

A computer-implemented method, computerized apparatus and computer program product for modified design debugging using differential trace back. An indication of an interface signal in a time unit in an execution resulting in a value miscompare between a design and a modification thereof is obtained. For each of the design and the modification, a data record detailing each signal value in each time unit, and a structure description detailing all components and interconnections thereamong, are obtained. A suspect root cause of the value miscompare is traced back from the interface signal in the time unit, the tracing back comprising comparing values in the data records of candidate signals selected based on the data records and the structure descriptions.

Modified design debugging using differential trace back

Checking a computer processor design for soft error handling. A baseline simulation of a computer processor design is monitored to identify a target processing cycle of the baseline simulation during which a predefined event occurs during the baseline simulation. The baseline simulation is performed in accordance with a software model of the computer processor design, and the event is associated with processing an instruction that directly involves a predefined error injection target. A test simulation of the computer processor design is performed in accordance with the software model of the computer processor design. An error is injected into the predefined error injection target during a target processing cycle of the test simulation. A determination is made as to whether the error is detected by error-checking logic of the computer processor design.

Checking a computer processor design for soft error handling

Error checking for a computer processor design under test. In multiple processing threads, and in accordance with a hardware model of a computer processor design under test, the instructions of multiple instruction sequences corresponding to the processing threads are processed, thereby resulting in an order in which the instructions are processed in accordance with the hardware model, and producing an actual result for each of the instructions. An expected result is determined for any of the instructions in accordance with a reference model of the computer processor design under test and in accordance with the order in which the instructions were processed in accordance with the hardware model. Any of the instructions whose expected result and actual result differ are identified.

Error checking of a multi-threaded computer processor design under test

Embodiments include a method for temporary pipeline marking for processor error workarounds. The method includes monitoring an execution unit pipeline of a processor for an event associated with a programmable instruction operational code that is predetermined to cause a stuck state resulting in an errant instruction execution. The execution unit pipeline is marked for a workaround action based on detecting the event. A clearing action is triggered based on the marking, where the triggering is conditionally triggered by a next instruction in the execution unit pipeline having a same instruction type as the programmable instruction operational code. The marking of the pipeline is cleared based on the triggering of the clearing action, where the clearing action is a subsequent pipeline flush event based on the next instruction having the same instruction type reaching a same pipeline stage that results in a stuck state prior to completion of the next instruction.

Temporary pipeline marking for processor error workarounds

A computer-implemented method may include retrieving a design netlist with a processor, identifying, via the processor, a logic structure in the design netlist, generating, via the processor, a driver based on the logic structure, applying, via the processor, a simulation and a formal model based on the driver, and testing, via the processor, an output of the simulation and the formal model.

Assuring chip reliability with automatic generation of drivers and assertions

Embodiments include a method for temporary pipeline marking for processor error workarounds. The method includes monitoring a pipeline of a processor for an event that is predetermined to place the processor in a stuck state that results in an errant instruction execution result due to the stuck state or repeated resource contention causing performance degradation. The pipeline is marked for a workaround action based on detecting the event. A clearing action is triggered based on the marking of the pipeline. The marking of the pipeline is cleared based on the triggering of the clearing action.

Embodiments include a computer system for temporary pipeline marking for processor error workarounds, the computer system having a processor configured to perform a method. The method includes monitoring a pipeline of the processor for an event that is predetermined to place the processor in a stuck state that results in an errant instruction execution result due to the stuck state or repeated resource contention causing performance degradation. The pipeline is marked for a workaround action based on detecting the event. A clearing action is triggered based on the marking of the pipeline. The marking of the pipeline is cleared based on the triggering of the clearing action.

Growing community of inventors

Kfar Saba, Israel

Erez Barak