International Business Machines Corporation

Sampan Arora

Shakti Kapoor

Manoj Dusanapudi

Sunil Suresh Hatti

Shubhodeep Roy Choudhury

Bhavani Shringari Nanjundiah

Divya S Anvekar

Vinod Bussa

Chakrapani Rayadurgam

Batchu Naga Venkata Satyanarayana

Sandip Bag

Shiraz Mohammad Zaman

Sai Rupak Mohanan

During a test pattern build, a test pattern generator pseudo-randomly selects an address for a selected lwarx instruction and builds the lwarx instruction using the pseudo-random address into a test pattern. Subsequently, the test pattern generator builds a store instruction after the lwarx instruction using the pseudo-random address. The store instruction is adapted to store the pseudo-random address in a predetermined memory location. The test pattern generator also builds an interrupt service routine that services an interrupt associated with the interrupt request; checks the predetermined memory location; determines that the pseudo-random address is located in the predetermined memory location; and executes a subsequent lwarx instruction using the pseudo-random address.

Predicting lwarx and stwcx instructions in test pattern generation and simulation for processor design verification/validation in interrupt mode

A system and method for generating a test case and a bit mask that allows a test case executor the ability to re-execute the test case multiple times using different machine state register bit sets. A test case generator creates a bit mask based upon identified invariant bits and semi-invariant bits. The test case generator includes compensation values corresponding to the semi-invariant bits into a test case, and provides the test case, along with the bit mask, to a test case executor. In turn, the test case executor dispatches the test case multiple times, each time with a different machine state register bit set, to a processor. Each of the machine state register bit sets places the processor in different modes.

System and method for testing multiple processor modes for processor design verification and validation

A system and method for predicting lwarx (Load Word And Reserve Index form) and stwcx (Store Word Conditional) instruction outcome is presented. A lwarx instruction establishes a reservation on an address/granule, and a stwcx instruction targeted to the same address/granule 'succeeds' only if the reservation for the granule still exists (conditional store). Since the reservation may be lost due to situations such as, for example, a processor (or another processor) executing a different lwarx or ldarx instruction (or other mechanism), which clears the first reservation and establishes a new reservation, the invention described herein builds test patterns in a manner that ensures, stwcx success and failure predictability. As a result, stwcx instructions are testable during test pattern execution.

System and method for predicting lwarx and stwcx instructions in test pattern generation and simulation for processor design verification and validation

A system and method for creating multiple test case scenarios from one test case by shuffling the test case instruction order while maintaining relative sub test case instruction order intact is presented. A test case generator generates and provides a test case that includes multiple sub test cases to a test case executor. In turn, the test case executor recursively schedules and dispatches the test case with different shuffled instruction orders to a processor in order to efficiently test the processor. In one embodiment, the test case generator provides multiple test cases to the test case executor. In another embodiment, the test case generator provides test cases to multiple test case executors that, in turn, shuffle the test cases and provide the shuffled test cases to their respective processor.

System and method for re-shuffling test case instruction orders for processor design verification and validation

A system and method for verifying cache snoop logic and coherency between instruction cache and data cache using instruction stream 'holes' that are created by branch instructions is presented. A test pattern generator includes instructions that load/store data into instruction stream holes. In turn, by executing the test pattern, a processor thread loads an L2 cache line into both instruction cache (icache) and data cache (dcache). The test pattern modifies the data in the dcache in response to a store instruction. In turn, the invention described herein identifies whether snoop logic detects the change and updates the icache's corresponding cache line accordingly.

System and method for verification of cache snoop logic and coherency between instruction & data caches for processor design verification and validation

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Karnataka, India

Sampan Arora