Proving latency associated with references to a data store

• US 8,280,832 B1
• Filed: 03/13/2009
• Issued: 10/02/2012
• Est. Priority Date: 03/04/2009
• Status: Active Grant

• Current Assignee: The MathWorks, Inc.
• Original Assignee: The MathWorks, Inc.
• Inventors: Englehart, Matthew, Mosterman, Pieter J.
• Primary Examiner(s): Vincent, David R
• Assistant Examiner(s): Smith, Paulinho E
• Application Number:
  US12/404,118
• Time in Patent Office: 1,299 Days
• Field of Search: None
• US Class Current: 706/45
• CPC Class Codes: G06F 30/00 Computer-aided design [CAD]
• CPC Class Codes: G06F 8/41 Compilation
• CPC Class Codes: G06N 5/022 Knowledge engineering; Knowledge acquisition

Abstract

A technique for analyzing a model, either statically or dynamically, checks the model for one or more specified patterns with respect to accessing a data store associated with the model. The patterns may include, for example, writing to the data store prior to reading the data store, reading the data store prior to writing to the data store, writing to the data store multiple times prior to reading the data store, reading the data store multiple times before writing to the data store, etc. The model may be an executable graphical model that is generated in a graphical modeling environment. A result may be generated based on analyzing the model and the result may be output.

Claims

1. One or more non-transitory computer-readable storage media storing instructions, the non-transitory computer-readable storage media comprising:

one or more instructions, executable by at least one processor to;

receive one or more patterns that are associated with accessing a data store during an execution of a model,

analyze the model to identify the one or more patterns associated with accessing the data store,

generate a result based on analyzing the model, the result indicating the identified one or more patterns, and

output the result.

2. The one or more non-transitory computer-readable media of claim 1, where the one or more patterns include at least one of:

reading data from the data store before the data is written to the data store, or

writing data to the data store before other data is read from the data store.

3. The one or more non-transitory computer-readable media of claim 1, where the data store is associated with an entity that indicates at least one of:

whether, within a time-step of execution, data is written to the data store, or

a number of times the data is written to the data store during the time-step of execution.

4. The one or more non-transitory computer-readable media of claim 3, where the entity is an auxiliary data store.

5. The one or more non-transitory computer-readable media of claim 3, where the model is analyzed to identify the one or more patterns associated with accessing a first block of the data store and the entity is a value stored in a second block of the data store.

6. The one or more non-transitory computer-readable storage media of claim 3, further comprising:

one or more instructions, executable by the at least one processor to;

evaluate the entity to identify whether the data is written to the data store before executing an instruction to read the other data from the data store, and

indicate, in the result, whether the data is written to the data store before executing the instruction to read the other data from the data store.

7. The one or more non-transitory computer-readable storage media of claim 3, further comprising:

one or more instructions, executable by the at least one processor to;

evaluate the entity to determine whether an instruction is executed to read the data from the data store before the data is written to the data store, and

indicate, in the result, whether the instruction is executed to read the data from the data store before the data is written to the data store.

8. The one or more non-transitory computer-readable storage media of claim 3, where the entity provides input to an expression that represents whether the data is written to the data store, and

the computer-readable storage medium further comprising:

one or more instructions, executable by the at least one processor to;

evaluate the expression to identify whether the data is written to the data store before the other data is read from the data store.

9. The one or more non-transitory computer-readable storage media of claim 8, where the expression is a Boolean expression, and

the computer-readable storage medium further comprising

one or more instructions, executable by the at least one processor to:

receive the one or more anomalous patterns specified by a user.

10. The one or more non-transitory computer-readable media of claim 3, where the entity includes a value that is incremented each time data is written to the data store, the value being reset at the end of the time-step of execution.

11. The one or more non-transitory computer-readable media of claim 1, further comprising:

one or more instructions, executable by the at least one processor to;

provide the result on a display device, for display, or

store the result in a storage device.

12. A method comprising:

analyzing a model, in a modeling environment, to identify whether data is written to a data store memory, associated with the model, by a set of one or more writers, before other data, previously written by the set of one or more writers, is read from the data store memory by a set of one or more readers, the analyzing being performed by one or more processors of a first device;

generating a result indicating whether the data is written to the data store memory before the other data is read from the data store memory based on analyzing the model, the generating being performed by the one or more processors; and

outputting the result to a second device, the outputting being performed by the one or more processors.

13. The method claim 12, where the data store memory is associated with an entity that indicates:

a number of times data is written to the data store memory.

14. The method of claim 13, where the entity is an auxiliary data store memory storing a value that is incremented each time data is written to the data store memory.

15. The method of claim 13, where analyzing the model includes:

examining the entity to identify whether the data is written to the data store memory before the other data is read from the data store memory during the time-step of execution.

16. The method of claim 12, where outputting the result further comprises:

providing the result for display on a display device associated with the second device, or

providing the result for storage in a memory of the second device.

17. A device comprising:

one or more processors to;

receive one or more patterns associated with accessing a data store memory during execution of a model,

analyze the model, in a modeling environment, to determine whether first data is written to the data store memory by a set of one or more writers before second data is read from the data store memory by a set of one or more readers,

generate a result based on analyzing the model, the result indicating whether the first data is written to the data store memory by the set of writers before the second data is read from the data store memory by the second set of components, and

output the result.

18. The device of claim 17, where the data store memory is associated with an entity that indicates:

a number of times the first data is written to the data store memory.

19. The device of claim 18, where, when analyzing the model, the one or more processors are to:

examine the entity to identify whether the first data is written to the data store memory before the second data is read from the data store memory.

20. The device of claim 17, where, when outputting the result, the one or more processors are to:

provide the result for display on a display device, or

provide the result for storage in a memory associated with the one or more processors.

21. A system comprising:

processing logic to;

receive a pattern the pattern being associated with accessing a data store associated with a model,

analyze the model to identify whether the model contains the received pattern,

generate a result based on analyzing the model, the result indicating whether the received pattern exists in the model, and

output the generated result.

22. One or more non-transitory computer-readable storage media storing instructions, the non-transitory computer-readable storage media comprising:

one or more instructions, executable by at least one processor to;

receive a request to read a data store in a model, the request being received from a reader associated with the model,

identify whether an entity associated with the data store indicates that the data store has been written by one or more writers associated with the model,

allow the data store to be read by the reader when the entity indicates that the data store has been written by at least one, but not more than one writer associated with the model, and

generate a result, when the entity does not indicate that the data store has been written by the at least one, but not more than one, writer, the result indicating at least one of;

the data store has not been written prior to the read request, or

the data store has been written more than once prior to the read request.

23. The one or more non-transitory computer-readable storage media of claim 22, further comprising:

one or more instructions, executable by the at least one processor to;

output the result.

24. The one or more non-transitory computer-readable storage media of claim 22, further comprising:

one or more instructions, executable by the at least one processor to;

reset the entity at the end of a time-step in the execution of the model.